JP5320849B2 - Uniaxial eccentric screw pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a uniaxial eccentric screw pump capable of delivering fluid at a predetermined delivery flow rate, without replacing a rotor or a stator, even when the rotor and the stator are changed in the volume by a temperature change and abrasion is caused in the rotor and the stator. <P>SOLUTION: This uniaxial eccentric screw pump 12 is provided so that a male screw rotor 13 is fitted to and inserted into an inner hole 14a of a female screw stator 14, and the rotor 13 relatively rotates to the stator 14, and can deliver the fluid from a first opening part 23, and is formed so that an outer diameter of the rotor 13 reduces and an inner diameter of the inner hole 14a of the stator 14 reduces, toward tip parts 13b and 14c from respective corresponding rear end parts 13a and 14b of the rotor 13 and the stator 14. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a uniaxial eccentric screw pump capable of adjusting a tightening margin or a gap between a rotor and a stator according to, for example, a volume change due to a temperature change of the stator or according to wear of the stator.

  An example of a conventional uniaxial eccentric screw pump is shown in FIG. 11 (a) (see, for example, Patent Document 1). In this uniaxial eccentric screw pump 1, a male screw type rotor 2 is fitted into an inner hole 3 a of a female screw type stator 3, and the rotor 2 rotates to suck fluid from the suction port 4 and discharge it from the discharge port 5. It is.

  The contour shape of the outer periphery of the rotor 2 is formed to have the same diameter from the rear end portion 2a on the suction port 4 side to the front end portion 2b on the discharge port 5 side. The contour shape of the inner periphery of the stator 3 inner hole 3a is formed such that the inner diameter has the same dimension from the rear end portion 3b on the suction port 4 side to the front end portion 3c on the discharge port 5 side. The central axis 6 of the rotor 2 and the central axis 7 of the inner hole 3a of the stator 3 are parallel to each other, and the amount of eccentricity between them is e.

  According to the single-shaft eccentric screw pump 1, the outer surface of the rotor 2 and the inner surface of the inner hole 3a of the stator 3 are rotated by revolving around the central shaft 7 of the stator inner hole 3a (planetary rotation) while the rotor 2 rotates. Can be moved from the suction port 4 side to the discharge port 5 side, whereby the liquid can be discharged from the discharge port 5. In order to maintain the liquid tightness of the space 8, for example, the stator 3 is made of synthetic rubber and the rotor 2 is made of metal.

Further, the central axis 6 of the rotor 2 shown in FIG. 11A is parallel to the central axis 7 of the inner hole 3a of the stator 3 with a distance of an eccentricity e therebetween. The rotor 2 is connected to the input shaft 11 via the universal joint 9, the connecting shaft 10, and the universal joint 9 so that the planetary rotational movement can be performed with respect to the rotor 3.
JP 2007-3343 A

  However, in the conventional uniaxial eccentric screw pump 1 shown in FIG. 11 (a), it is necessary to change the diameter of the rotor 2 in accordance with the temperature of the liquid discharged by this pump. Is discharged, it is necessary to replace the rotor 2 with a diameter corresponding to the temperature.

  This is because when the temperature of the liquid rises, the volume of the synthetic rubber stator 3 expands, and the volume of the space 8 formed between the rotor 2 and the stator 3 decreases, thereby reducing the discharge flow rate. Because. Therefore, for example, when a relatively high temperature liquid is discharged using the pump 1 having the stator 3 having the same specification size, the diameter is relatively small compared to when a relatively low temperature liquid is discharged. It is necessary to use the rotor 2.

  In addition, when the synthetic rubber stator 3 is in contact with the rotor 2 and wear of a size larger than a predetermined amount occurs, the liquid tightness of the space 8 formed between the rotor 2 and the stator 3 is lowered. Therefore, in order to ensure this liquid tightness, it is necessary to replace the stator 3 with a new one.

  The present invention has been made in order to solve the above-described problems. Even when the volume of the rotor and the stator changes due to a temperature change or the rotor and the stator are worn, the rotor or the stator is not replaced. Another object of the present invention is to provide a uniaxial eccentric screw pump capable of discharging a fluid at a predetermined discharge flow rate.

In the uniaxial eccentric screw pump according to the present invention, a male screw type rotor is fitted into an inner hole of a female screw type stator, and the rotor rotates relative to the stator so that fluid can be discharged from a discharge port. In the eccentric screw pump, the rotor and the stator are formed such that the outer diameter of the rotor decreases and the inner diameter of the inner hole of the stator decreases as it goes from the corresponding one end to the other end . In a state where the rotor is fitted in the inner hole of the stator, the respective central axes of the rotor and the stator approach each other and cross each other from the other end side of the rotor toward the one end side. It is characterized by this.

  According to the uniaxial eccentric screw pump according to the present invention, fluid can be discharged from the discharge port when the rotor rotates relative to the stator. Then, for example, when a relatively high temperature (or low temperature) fluid is discharged or when the rotor or the stator is worn compared to the current state, the allowance between the outer surface of the rotor and the inner surface of the stator is When the rotor becomes larger (or smaller), or when the gap becomes smaller (or larger), the outer surface of the rotor and the inner surface of the stator are mutually connected in advance or when necessary so that a predetermined tightening allowance or clearance is obtained. The rotor can be moved in the direction of the central axis relative to the stator in the direction of separation (or approach).

  As described above, the rotor can be moved relative to the stator in a direction in which the outer surface of the rotor and the inner surface of the stator are separated from each other or approached from each other. This is because the outer diameter of the rotor becomes smaller and the inner diameter of the stator becomes smaller toward the end portion.

Further, when the rotor rotates relative to the stator, the rotation trajectory of the central axis of the rotor has a substantially conical shape. Therefore, for example, when the rotor and the input shaft for rotationally driving the rotor are connected via the connecting portion, the connecting portion is disposed at the intersection of the central axis of the rotor and the central axis of the stator. Thus, the rotor can be rotated relative to the stator using one connecting portion.

  Further, since the rotor and the input shaft are connected by a single connecting portion with only a declination between them, the reaction force of the operating fluid pressure generates an axial external component force at the connecting portion when the pump is operating. However, this external component force in the axial direction does not shift the positional relationship between the central axis of the rotor and the central axis of the stator. As a result, the reaction force of the working fluid pressure does not cause partial wear on the inner surface of the end portion on the connecting portion side of the stator.

  In the uniaxial eccentric screw pump according to the present invention, a cross-sectional area perpendicular to the central axis of the inner hole in a space formed between the outer surface of the rotor and the inner surface of the inner hole of the stator is the central axis. The inner holes of the rotor and the stator can be formed so as to be substantially the same at any of the positions.

  According to this uniaxial eccentric screw pump, when the rotor is rotated relative to the stator, a space formed between the outer surface of the rotor and the inner surface of the inner hole of the stator is changed from the suction side to the discharge side of the stator. Therefore, the fluid accommodated in this space can be sucked from the suction side of the stator and discharged from the discharge side. Here, if the cross-sectional area of the space perpendicular to the central axis of the inner hole is substantially the same at any position of the central axis of the inner hole, the pressure and volume of the fluid contained in the space The fluid can be transferred in the pump while the pressure is kept substantially constant. Therefore, the fluid can be discharged without forcibly compressing or expanding the fluid without affecting the quality.

  Furthermore, in the uniaxial eccentric screw pump according to the present invention, a space formed between the outer surface of the rotor and the inner surface of the inner hole of the stator is in a direction perpendicular to the central axis of the inner hole, and The dimension in the direction passing through the central axis of the rotor can be formed so as to increase from one end of the stator to the other end.

  In this way, the cross-sectional area perpendicular to the central axis of the inner hole in the space formed between the outer surface of the rotor and the inner surface of the inner hole of the stator is substantially the same at any position of the central axis. Can be. Because this uniaxial eccentric screw pump is formed so that the outer diameter of the rotor becomes smaller and the inner diameter of the stator becomes smaller as it goes from the corresponding one end to the other end of each of the rotor and the stator. This is because the lengths of the outer and inner peripheries are shortened from one end to the other end.

  Therefore, the dimension of the space in the direction perpendicular to the central axis of the inner hole is formed so as to increase from one end of the stator to the other end. As a result, the cross-sectional area perpendicular to the central axis of the inner hole in the space formed between the outer surface of the rotor and the inner surface of the inner hole of the stator is substantially the same at any position of the central axis. Can be.

  In the uniaxial eccentric screw pump according to the present invention, a cross-sectional area perpendicular to the central axis of the inner hole in the space formed between the outer surface of the rotor and the inner surface of the inner hole of the stator is the rotor and The inner holes of the rotor and the stator can be formed so as to become smaller from the corresponding one end to the other end of the stator.

  In this case, for example, when the rotor is rotated relative to the stator in a predetermined direction, a space formed between the outer surface of the rotor and the inner surface of the inner hole of the stator is formed inside the stator from the suction side. As it moves to the discharge side, the volume can be reduced, and the pressure of the fluid accommodated in this space can be increased. Thus, for example, when the fluid is a liquid, it is possible to suppress the fluid from being vaporized in the space and the discharge port.

  Moreover, the uniaxial eccentric screw pump which concerns on this invention WHEREIN: The moving mechanism for moving the said stator relatively to the direction of the central axis of the inner hole of the said stator with respect to the said rotor can be provided.

  In this case, for example, when the tightening allowance between the outer surface of the rotor and the inner surface of the stator becomes larger or smaller due to temperature changes of the stator and the rotor, or due to wear of the stator or the rotor, or the gap becomes smaller. When this is the case, the moving mechanism moves the rotor relative to the stator in a direction in which the outer surface of the rotor and the inner surface of the stator are separated from each other or approach each other. It can be moved relatively in the direction of the central axis.

  Further, in the uniaxial eccentric screw pump according to the present invention, the moving mechanism connects the moving casing provided with the stator, the fixed casing provided with the rotor, and the moving casing and the fixed casing to each other. And a configuration in which the stator can be moved relative to the rotor in the direction of the central axis of the inner hole by rotating the movable casing in the screw direction of the screw portion. It can be.

  In this way, the stator can be moved relatively easily in the direction of the central axis of the inner hole with respect to the rotor by rotating the movable casing in the screw direction of the screw portion.

  In the uniaxial eccentric screw pump according to the present invention, the moving mechanism is connected to the fixed-side input shaft for transmitting rotational power to the rotor and the rotor, and transmits the rotation of the input shaft to the rotor. A movable shaft for connecting the movable shaft to the input shaft so as to be extendable and contractable in the axial direction, a rotational power transmission unit for transmitting the rotation of the input shaft to the movable shaft, and the input shaft A moving operation part inserted into an insertion hole formed in the axial direction and coupled to the moving shaft via a screw part, and by rotating the moving operation part in the screw direction of the screw part, It can be set as the structure which can move a rotor relatively to the direction of the central axis of the said internal hole with respect to the said stator.

  In this case, without rotating the stator or the input shaft or moving the input shaft in the direction of the central axis of the inner hole, the rotor is moved with respect to the stator by rotating the moving operation portion in the screw direction of the screw portion. It can be moved relatively in the direction of the central axis of the inner hole. That is, for example, the stator may be connected to a fixed pipe, or the input shaft may be connected to the rotating shaft of the drive unit. In such a case, the stator or the input shaft may be rotated or the central axis direction may be However, it is possible to easily adjust the tightening margin of the rotor and the stator without rotating the stator and the input shaft.

  In the uniaxial eccentric screw pump according to the present invention, the moving mechanism may be configured such that the stator is relatively movable in the direction of the central axis of the inner hole with respect to the fixed casing, and the protrusion provided on the stator and the An adjustment bolt that is inserted into one of the edges formed in the fixed casing and screwed into the other is rotated in the screw direction, whereby the stator is positioned on the central axis of the inner hole with respect to the rotor. It can be set as the structure which can be moved relatively to a direction.

  In this case, the stator can be moved relative to the rotor in the direction of the central axis of the inner hole by rotating the adjustment bolt in the screw direction. For example, the rotor may be connected to the rotating shaft of the drive unit, or the fixed casing may be connected to the fixed pipe, so that the rotor and the fixed casing are not moved or rotated in the direction of the central axis. In addition, adjustments such as a tightening allowance of the rotor and the stator can be easily performed.

  Furthermore, in the single-shaft eccentric screw pump according to the present invention, the moving mechanism is connected to the fixed-side input shaft for transmitting rotational power to the rotor and the rotor, and transmits the rotation of the input shaft to the rotor. A moving shaft for connecting the moving shaft to the input shaft so as to extend and contract in the axial direction, a rotational power transmission unit for transmitting the rotation of the input shaft to the moving shaft, and the rotor. An urging unit that urges the input shaft in the extending direction may be provided.

  If it does in this way, since the energizing means is energizing in the direction which presses the outer surface of a rotor to the inner surface of a stator, it will be in the state which is pressing the outer surface of a rotor with the predetermined force against the inner surface of a stator. Yes. The stator or rotor is deformed (expanded or contracted) in a direction in which the tightening margin of the contact surface between the rotor and the stator is increased or decreased due to, for example, a temperature change of the stator and the rotor or wear of the stator or the rotor. The rotor can move in the axial direction to absorb the deformation. Thereby, the interference between the outer surface of the rotor and the inner surface of the stator can be automatically adjusted so as to be maintained at a substantially predetermined size.

  In the uniaxial eccentric screw pump according to the present invention, the biasing means can be a compression spring.

  If it does in this way, it is a comparatively simple structure, Comprising: The rotor can be urged | biased with respect to an input shaft with the spring force of a compression spring, without using external power.

  Further, in the uniaxial eccentric screw pump according to the present invention, the biasing means is a compression spring and has a bimetal structure, and the bimetal structure shortens the compression spring as the temperature rises, and the bimetal structure as the temperature decreases. The compression spring can be extended.

  Now, when the temperature of the stator and the rotor changes and the stator or the rotor is deformed, the allowance for the contact surface between the rotor and the stator becomes larger or smaller. At this time, since the urging means urges the outer surface of the rotor in a direction in which the outer surface of the rotor is pressed against the inner surface of the stator, the rotor moves in a direction to absorb the increase or decrease in the tightening margin of the contact surface. Can do. At this time, since the compression spring as the urging means is compressed or extended, the force with which the urging means presses the outer surface of the rotor against the inner surface of the stator changes. The spring can be suppressed or eliminated by shortening or extending according to the temperature change. As a result, regardless of the temperature changes of the stator and the rotor, the tightening allowance of the contact surface between the rotor and the stator can be automatically adjusted so as to be maintained at a predetermined size with relatively high accuracy.

  Furthermore, in the uniaxial eccentric screw pump according to the present invention, the stator may be made of synthetic rubber or synthetic resin.

  Thus, by forming the stator with synthetic rubber or synthetic resin, it is possible to ensure the sealing performance of the space formed by the outer surface of the rotor and the inner surface of the stator inner hole.

  In the uniaxial eccentric screw pump according to the present invention, the stator has a mounting portion attached to a casing and a flexible body, and the flexible body is deformable in the direction of the central axis of the inner hole of the stator. There can be.

  In this case, for example, by adopting a configuration in which the discharge pressure of the fluid acts on the end surface of the one end portion in which the outer end portion of the rotor having the smaller outer diameter is accommodated among the both end portions of the stator, the fluid According to the discharge pressure, the stator is displaced in the central axis direction, and the contact pressure between the inner surface of the inner hole of the stator and the outer surface of the rotor can be automatically adjusted. Thereby, fluid leakage can be prevented and fluid can be discharged at a predetermined pressure.

  Further, in the uniaxial eccentric screw pump according to the present invention, the stator has an attachment portion attached to a casing and a stator main body portion, and the stator main body portion is orthogonal to the central axis of the inner hole of the stator. It can be deformable in the direction.

  In this case, for example, by adopting a configuration in which the discharge pressure of the fluid acts on the outer peripheral surface of the stator body, the direction in which the stator body is orthogonal to the central axis according to the discharge pressure of the fluid. Thus, the contact pressure between the inner surface of the inner hole of the stator body and the outer surface of the rotor can be automatically adjusted. Thereby, fluid leakage can be prevented and fluid can be discharged at a predetermined pressure.

  According to the uniaxial eccentric screw pump according to the present invention, the outer diameter of the rotor is reduced and the inner diameter of the stator is reduced from the corresponding one end to the other end of the rotor and the stator. Therefore, when the volume of the rotor or stator changes due to temperature changes, or when the rotor or stator is worn, the direction in which the outer surface of the rotor and the inner surface of the stator are separated or approach each other in advance or when necessary. In addition, the rotor can be moved in the direction of the central axis relative to the stator.

  Accordingly, the fluid can be continuously discharged at a predetermined discharge flow rate without replacing the rotor or the stator. Therefore, for example, it is not necessary to prepare a plurality of rotors and stators having different dimensions according to the temperature of the fluid to be discharged, and attach and use the rotors and stators having dimensions corresponding to the temperature of the fluid. Even when the rotor or stator is worn, it is economical because it is not necessary to replace the rotor or stator.

  Hereinafter, a first embodiment of a uniaxial eccentric screw pump according to the present invention will be described with reference to FIGS. As shown in FIG. 1, the uniaxial eccentric screw pump 12 has a male screw type rotor 13 fitted in an inner hole 14 a of a female screw type stator 14, and the rotor 13 rotates relative to the stator 14. Any fluid from a viscosity to a high viscosity can be transferred or filled with high flow accuracy. This fluid includes liquids, gases, and fluids such as slurries and granular materials.

  As shown in FIG. 1, the uniaxial eccentric screw pump 12 is a rotary displacement pump, and includes a female screw type stator 14 and a male screw type rotor 13.

  As shown in FIGS. 1 and 2A, the rotor 13 is formed in, for example, a single thread (leaf) male screw shape, has a longitudinal cross-sectional shape of a substantially perfect circle, and the helical pitch is within the stator 14. It is set to 1/2 of the pitch of the holes 14a. The rotor 13 is made of a metal such as stainless steel and is inserted into the inner hole 14a of the stator 14. Further, as shown in FIG. 1, a connecting shaft 15 is integrally provided at the rear end portion 13 a of the rotor 13, and the connecting shaft 15 is connected to the input shaft 18 via the connecting portion 16.

  As shown in FIG. 1, the connecting portion 16 includes an insertion hole 16 a formed at the base end portion of the connecting shaft 15, and a connecting pin 16 b that is swingably inserted into the insertion hole 16 a. The connecting pin 16 b is provided at the pin receiving portion 17, and the pin receiving portion 17 is provided at the distal end portion of the input shaft 18.

  As shown in FIG. 1, the input shaft 18 is rotatable via two bearings 19 and is provided inside the fixed casing 20 so as not to move in the axial direction. The base end portion of the input shaft 18 is connected to a rotating shaft of a rotor driving unit (not shown). The rotor drive unit is an electric motor such as a stepping motor or a servo motor.

  As shown in FIGS. 1 and 2B and 2C, the stator 14 is formed in a substantially cylindrical shape having, for example, two threaded inner holes 14a, and a longitudinal section of the inner hole 14a. The shape is an ellipse, for example, made of synthetic rubber. Both ends of the oval having a cross-sectional shape of the inner hole 14a are formed as semicircles, and each end of the pair of semicircles is connected by a straight line. The inner holes 14 a are twisted in the direction of the central axis 30 at a pitch twice that of the rotor 13.

  However, the stator 14 can be formed of a synthetic resin including engineering plastics such as Teflon (registered trademark), polyacetal, cast nylon. Thus, by forming the stator 14 from synthetic rubber or synthetic resin, the liquid tightness (sealability) of the space 25 formed by the outer surface 13c of the rotor 13 and the inner surface 14e of the stator inner hole 14a is ensured. be able to.

  As shown in FIG. 1, the stator 14 is hermetically mounted in the movable casing 21 and the fixed casing 20. An end stud 32 is fastened to the front end portion of the movable casing 21 with a bolt. Between the end stud 32 and the front end portion of the movable casing 21, a flange-shaped portion 14f (attachment portion) of the stator 14 is provided. Is sandwiched and attached. In this way, the stator 14 is fixedly attached to the movable casing 21.

  Further, as shown in FIG. 1, the stator 14 includes a flange-shaped portion 14f, a relatively thin flexible barrel portion 14d, and a stator main body portion 14h. The flexible barrel portion 14d and the outer peripheral surface of the stator main body portion 14h A cylindrical gap 22 is formed between the inner peripheral surface of the movable casing 21.

  With this configuration, when the fluid is sucked from the second opening 24 described later and discharged from the first opening 23, the high-pressure discharge fluid that fills the first opening 23 is the discharge-side end face 14g (see FIG. 3), the flexible body portion 14d elastically deforms (extends) in the direction of the central axis, thereby automatically increasing the contact pressure between the stator 14 and the rotor 13, and the inner surface 14e of the stator 14 and the rotor 13 The degree of sealing of the space 25 formed with the outer surface 13c of can be increased.

  When a cylindrical gap 22 is formed between the outer peripheral surface of the stator main body 14 h and the inner peripheral surface of the movable casing 21, fluid is sucked from a first opening 23 described later and discharged from the second opening 24. In this case, the outer peripheral surface of the stator main body portion 14h made of synthetic rubber, for example, can be compressed by the pressure of the fluid in the fixed casing 20, so that the inner surface 14e of the stator main body portion 14h of the stator 14 and the outer surface of the rotor 13 are compressed. The sealing degree of the space 25 formed with 13c can be raised.

  Further, as shown in FIG. 3, the moving casing 21 and the fixed casing 20 are connected to each other via a moving mechanism 26. The moving mechanism 26 is for moving the stator 14 relative to the rotor 13 in the direction of the central axis 30 of the inner hole 14 a of the stator 14.

  As shown in FIG. 1, the moving mechanism 26 includes a moving casing 21 in which the stator 14 is provided, a fixed casing 20 in which the rotor 13 is provided, and a screw that connects the moving casing 21 and the fixed casing 20 to each other. Part 27. The screw portion 27 includes a male screw portion 27 a provided in the movable casing 21 and a female screw portion 27 b provided in the fixed casing 20. A lock nut 28 is screwed into the male thread portion 27 a of the movable casing 21. Further, an O-ring 29 is mounted in an annular gap between the outer peripheral surface of the movable casing 21 and the inner peripheral surface of the fixed casing 20, and this gap is sealed.

  According to this moving mechanism 26, by rotating the moving casing 21 in the screw direction of the screw portion 27, the stator 14 is moved relative to the rotor 13 in the direction of the central axis 30 of the inner hole 14 a. Can be moved to. As a result, the interference between the inner surface 14e of the stator 14 and the outer surface 13c of the rotor 13 can be adjusted.

  As shown in FIG. 3, the first opening 23 is formed in the end stud 32, and the second opening 24 is formed in the fixed casing 20. The first opening 23 can be used as a discharge port and a suction port, and the second opening 24 can be used as a suction port and a discharge port. The first opening 23 communicates with the front end opening of the inner hole 14a formed in the stator 14, and the second opening 24 communicates with the rear end opening of the inner hole 14a. Yes.

  Further, as shown in FIG. 1, a partition wall 33 is provided between the bearing 19 and the second opening 24 so that a fluid such as a transfer liquid transferred by the pump 12 does not come into contact with the bearing 19. Yes. The partition wall 33 is attached so that the outer peripheral portion is in close contact with the inner peripheral surface of the fixed casing 20, and the inner peripheral portion is attached to the outer peripheral surface of the input shaft 18 via a mechanical seal 34. Thus, the partition wall 33 can seal the fluid chamber through which the fluid passes with respect to the bearing chamber in which the bearing 19 and the like are provided.

  In addition, 35 shown in FIG. 1 is a discharge hole for discharging a fluid (liquid), and 36 is a liquid reservoir.

  Next, the rotor 13 and the stator 14 will be described with reference to FIGS. FIG. 2A is a perspective view of the rotor 13. FIG. 2B is a perspective view of the stator 14 viewed from the front end portion 14c side, and FIG. 2C is a perspective view of the stator 14 viewed from the rear end portion 14b side. FIG. 3 is an enlarged longitudinal sectional view for explaining the positional relationship between the stator 14 and the rotor 13.

  As shown in FIGS. 2 and 3, the rotor 13 and the stator 14 have an outer diameter that increases from the rear end portions 13 a and 14 b on the connecting shaft 15 side toward the end portions 13 b and 14 c on the end stud 32 side. The inner diameter of the inner hole 14a of the stator 14 is formed to be smaller as it becomes smaller. Specifically, as shown in FIG. 3, the ratio of the diameter of the rear end portion 13a on the large diameter side of the rotor 13, the diameter of the tip portion 13b on the small diameter side, and the length of the rotor 13 is about 20:10: 55. The ratio of the short diameter of the rear end portion 14b on the large diameter side of the inner hole 14a having the elliptical cross section of the stator 14, the short diameter of the front end portion 14c on the small diameter side, and the length of the inner hole 14a of the stator 14 is about 20:10:55.

  According to the uniaxial eccentric screw pump 12 shown in FIG. 1 configured as described above, when a rotor driving unit (not shown) is rotationally driven in a predetermined direction, the rotation of the rotor driving unit is caused to cause the input shaft 18 and the coupling unit 16 to rotate. , And transmitted to the rotor 13 via the connecting shaft 15, the rotor 13 can be rotated in a predetermined direction. Then, by rotation of the rotor 13, a fluid such as a liquid can be sucked from the second opening 24 (or the first opening 23) and discharged from the first opening 23 (or the second opening 24).

  Then, for example, when a relatively high temperature (or low temperature) fluid is discharged compared to the current state, or when the rotor 13 or the stator 14, particularly the stator 14 is worn, the outer surface 13 c of the rotor 13. The outer surface 13c of the rotor 13 and the inner surface 14e of the stator 14 are preliminarily or whenever the tightening allowance between the rotor 14 and the inner surface 14e of the stator 14 becomes large (or small) or becomes a predetermined tightening allowance. The rotor 13 can be moved in the direction of the central axis 30 relative to the stator 14 in a direction in which they are separated (or approached) from each other. This is an adjustment function that was not possible with the conventional uniaxial eccentric screw pump 1 shown in FIG.

  Here, the temperature of the transfer fluid and the tightening allowance will be described. When discharging a relatively high-temperature (or low-temperature) fluid, the volume of the stator 14 made of synthetic resin such as synthetic rubber is expanded (or contracted) in comparison with the metal rotor 13, and the outer surface of the rotor 13. The tightening margin between 13c and the inner surface 14e of the stator 14 becomes large (or small). When the tightening margin between the outer surface 13c of the rotor 13 and the inner surface 14e of the stator 14 increases (or decreases), the volume of the space 25 formed between the rotor 13 and the stator 14 decreases (or increases). As a result, the discharge flow rate decreases (or increases). Therefore, when the tightening margin becomes large (or small), the tightening margin is adjusted by moving the stator 14 in the direction of the central axis 30 in advance or every time in order to obtain a predetermined tightening margin. Thereby, the fluid can be discharged at a predetermined constant flow rate.

  In addition, when the synthetic rubber stator 14 is in contact with the rotor 13 and wears larger than a predetermined size, the sealing property (liquid tightness) of the space 25 formed between the rotor 13 and the stator 14 is obtained. ) (In order to secure a predetermined tightening allowance), the stator 14 can be moved along the central axis 30 in a direction in which the inner surface 14e of the stator 14 is pressed against the outer surface 13c of the rotor 13. The fluid can be discharged at a predetermined flow rate.

  Furthermore, another object of adjusting the tightening allowance is to seal the space 25 formed by the inner surface 14e of the inner hole 14a of the stator 14 and the outer surface 13c of the rotor 13 with a predetermined degree of sealing, so that the pressure fluid is predetermined. This is to enable discharge with pressure. Here, when the tightening margin is increased, the sealing degree of the space 25 can be increased, but the rotational frictional resistance of the rotor 13 is increased by the contact between the inner surface 14e of the stator 14 and the outer surface 13c of the rotor 13. If the tightening margin is reduced, the sealing degree of the space 25 is lowered, but the rotational frictional resistance of the rotor 13 can be reduced. Therefore, in order to obtain an appropriate sealing degree of the space 25 and an appropriate rotational frictional resistance, an appropriate tightening allowance can be set.

  Next, when the rotor 13 is moved in the direction of the central axis 30 relative to the stator 14, it can be performed by operating the moving mechanism 26 shown in FIG. First, the lock nut 28 is loosened. Next, by rotating the movable casing 21 in the screw direction of the threaded portion 27 by a predetermined number of rotations, the stator 14 is relatively easy with respect to the rotor 13 in the direction of the central axis 30 of the inner hole 14a. Can be moved forward and backward by a predetermined dimension. Thereafter, the lock nut 28 is tightened to fix the movable casing 21 to the fixed casing 20. This completes the adjustment of the tightening allowance.

  In this way, the stator 14 can be moved back and forth in the direction of the central axis 30 relative to the rotor 13 in such a direction that the outer surface 13c of the rotor 13 and the inner surface 14e of the stator 14 are separated or approach each other. The outer diameter of the rotor 13 is reduced and the inner diameter of the inner hole 14a of the stator 14 is reduced as it goes from the corresponding rear end portions 13a, 14b of the rotor 13 and the stator 14 to the front end portions 13b, 14c. It is because it is formed.

  Therefore, for example, it is not necessary to prepare a plurality of rotors and stators having different dimensions according to the temperature of the fluid to be discharged, and attach and use the rotors and stators having dimensions corresponding to the temperature of the fluid. Even when the rotor 13 or the stator 14 is worn, it is economical because it is not necessary to replace the rotor 13 or the stator 14.

  Further, as shown in FIG. 3, the uniaxial eccentric screw pump 12 is configured such that the central shafts 31 and 30 of the rotor 13 and the stator 14 are rotors in a state where the rotor 13 is fitted in the inner hole 14 a of the stator 14. 13 are configured to approach each other toward the rear end portion 13a side from the front end portion 13b side and cross at an intersection O of the connecting portion 16. Specifically, the distance between the central axes 31 and 30 of the rotor 13 and the stator 14 at the rear end portion 13 a of the rotor 13, and the central axes 31 and 30 of the rotor 13 and the stator 14 at the tip end portion 13 b of the rotor 13. The ratio between the distance and the length of the rotor 13 is, for example, about 2: 4: 55.

  With this configuration, when the rotor 13 rotates relative to the stator 14, the rotation locus of the central shaft 31 of the rotor 13 becomes a substantially conical shape. Therefore, when connecting the rotor 13 and the input shaft 18 for rotationally driving the rotor 13 via the connecting part 16, the connecting part 16 is connected to the central axis 31 of the rotor 13 and the central axis 30 of the stator 14. The rotor 13 can be rotated relative to the stator 14 by using one connecting portion 16. In addition, if only one connecting portion 16 is used in this way, the number of parts of the single-shaft eccentric screw pump 12 can be reduced as compared with the prior art, and the overall length of the pump can be reduced as compared with the conventional one. Can be.

  Furthermore, the cross-sectional area perpendicular to the central axis 30 of the inner hole 14a in the space 25 formed between the outer surface 13c of the rotor 13 and the inner surface 14e of the inner hole 14a of the stator 14 shown in FIG. The inner holes 14a of the rotor 13 and the stator 14 are formed so as to be substantially the same at any of these positions.

  In this way, when the rotor 13 is rotated relative to the stator 14, a space 25 formed between the outer surface 13 c of the rotor 13 and the inner surface 14 e of the inner hole 14 a of the stator 14 is Since the fluid moves from the second opening 24 side (suction port side) toward the first opening 23 side (discharge port side), the fluid contained in the space 25 is sucked from the second opening 24 and first The liquid can be discharged from the opening 23. Here, the space 25 is formed so that the cross-sectional area perpendicular to the central axis 30 of the inner hole 14a is substantially the same at any position of the central axis 30 of the inner hole 14a. The fluid can be transferred in the stator 14 in a state where the pressure and volume of the contained fluid are kept substantially constant. Therefore, the fluid can be discharged without forcibly compressing or expanding the fluid without affecting the quality.

  And, as shown in FIG. 3, the direction of the space 25 formed between the outer surface 13c of the rotor 13 and the inner surface 14e of the inner hole 14a of the stator 14 is perpendicular to the central axis 30 of the inner hole 14a. And the dimension of the direction which passes along the central axis 31 of the rotor 13 is formed so that it may become large as it goes to the front-end | tip part 14c from the rear-end part 14b of the stator 14. FIG.

  When formed in this way, the cross-sectional area perpendicular to the central axis 30 of the inner hole 14a of the space 25 formed between the outer surface 13c of the rotor 13 and the inner surface 14e of the inner hole 14a of the stator 14 is the central axis. It can be made substantially the same at any of the 30 positions. This is because, according to the uniaxial eccentric screw pump 12, the outer diameter of the rotor 13 decreases as the rotor 13 and the stator 14 respectively move from the corresponding rear end portions 13a, 14b toward the front end portions 13b, 14c, and the stator 14 This is because the inner diameter is formed to be smaller, and the lengths of the outer and inner peripheries become shorter from the rear end portions 13a and 14b toward the front end portions 13b and 14c.

  Therefore, the space 25 is formed such that the dimension of the space 25 in the direction perpendicular to the central axis 30 of the inner hole 14a increases from the rear end portion 14b of the stator 14 toward the front end portion 14c. As a result, the cross-sectional area perpendicular to the central axis 30 of the inner hole 14a of the space 25 formed between the outer surface 13c of the rotor 13 and the inner surface 14e of the inner hole 14a of the stator 14 is It can be made to be substantially the same at the position.

  However, in the space 25 formed between the outer surface 13c of the rotor 13 and the inner surface 14e of the inner hole 14a of the stator 14, the cross-sectional areas perpendicular to the central axis 30 of the inner hole 14a are respectively the rotor 13 and the stator 14. The inner holes 14a of the rotor 13 and the stator 14 may be formed so as to become smaller (or larger) from the corresponding rear end portions 13a, 14b toward the front end portions 13b, 14c.

  In this way, for example, when the rotor 13 is rotated relative to the stator 14 in a predetermined direction, the space 25 formed between the outer surface 13 c of the rotor 13 and the inner surface 14 e of the inner hole 14 a of the stator 14. However, as the inside of the pump 12 moves from the second opening 24 side (suction port side) to the first opening 23 side (discharge side), the volume can be reduced (or increased). The pressure of the fluid stored in the space 25 can be gradually increased (or decreased).

  Thus, for example, when the pressure of the fluid is increased, when the fluid is a liquid, the vaporization of the fluid in the space 25 and the first opening 23 can be suppressed. If the pressure of the fluid is lowered, for example, the fluid can be discharged without destroying or deforming the granular material contained in the fluid.

  As shown in FIG. 3, the outer diameter of the rotor 13 decreases and the inner hole of the stator 14 decreases from the corresponding rear end portions 13 a and 14 b of the rotor 13 and the stator 14 toward the front end portions 13 b and 14 c. 14a is formed so that the inner surface 14c of the rotor 13 and the inner surface 14e of the stator 14 are spaced apart from each other or approach each other. Easy to move forward and backward in the direction.

  Thereby, the assembly and disassembly of the rotor 13 and the stator 14 can be easily performed, and the inside of the rotor 13 and the stator 14 and the pump 12 can be easily cleaned.

  Further, as shown in FIG. 3, the stator 14 formed of synthetic rubber or the like is attached to the movable casing 21 via a flange-shaped portion 14 f, and the flexible body portion 14 d can be deformed in the direction of the central axis 30 of the stator 14. The configuration is as follows.

  In this case, for example, the discharge pressure of the fluid acts on the end surface 14g of the front end portion 14c of the stator main body portion 14h in which the front end portion 13b having the smaller outer diameter of the rotor 13 out of both end portions of the stator 14 is accommodated. In this case, the flexible body 14d is extended and displaced in the direction of the central axis 30 in accordance with the fluid discharge pressure, so that the contact pressure between the inner surface 14e of the inner hole 14a of the stator 14 and the outer surface 13c of the rotor 13 is increased. Can be adjusted automatically. Thereby, fluid leakage can be prevented and fluid can be discharged at a predetermined pressure. Note that the degree of sealing between the rotor 13 and the stator 14 can be automatically adjusted even when the discharge pressure is relatively high, low, or slowly fluctuates.

  Further, as shown in FIG. 3, the stator 14 is formed of an elastic material such as synthetic rubber, and a gap 22 is formed between the outer peripheral surface of the stator 14 and the inner peripheral surface of the movable casing 21. Thus, the flexible body 14 d of the stator 14 is configured to be deformable in a direction orthogonal to the central axis 30.

  The reason for this is that even when the rotor 13 moves with a slight deviation from the movement locus indicated by the geometric theory, the deviation is absorbed by the deformation of the flexible body 14d of the stator 14. This is because the fluid can be discharged with high performance.

  The movement locus of the rotor 13 indicated by the geometric theory is that the rotor 13 revolves in a conical shape while maintaining a predetermined deflection angle 91 between the central axis 31 of the rotor 13 and the central axis 30 of the stator 14. This is the trajectory when As a reason that the rotor 13 may move with a slight deviation from this theoretical movement locus, the pump due to the manufacturing accuracy and assembly accuracy of the single-shaft eccentric screw pump 12, fluid pressure, etc. The influence of the deformation | transformation of 12 and the vibration etc. which generate | occur | produce at the time of driving | operation are considered.

  Next, a uniaxial eccentric screw pump 38 according to a second embodiment of the present invention will be described with reference to FIG. The difference between the second embodiment shown in FIG. 4 and the first embodiment shown in FIG. 1 is that in the first embodiment shown in FIG. 1, the outer peripheral surface of the stator 14 and the inner peripheral surface of the movable casing 21 are different. In the second embodiment shown in FIG. 4, the stator 14 is accommodated in a cylindrical outer cylinder portion 39, and the outer cylinder portion 39 is This is where the outer peripheral surface is mounted in close contact with the inner peripheral surface of the movable casing 21. Other than this, the second embodiment is the same as the first embodiment, and the equivalent parts are denoted by the same reference numerals, and the description thereof is omitted.

  The outer cylinder portion 39 is formed of, for example, a hard material such as metal, and is attached to the stator 14 with its inner peripheral surface in close contact with the outer peripheral surface of the stator 14. As described above, when the outer cylindrical portion 39 is attached to the outer peripheral surface of the stator 14, even if the fluid pressure in the fixed casing 20 is applied to the outer cylindrical portion 39, for example, the outer peripheral surface of the stator 14 made of synthetic rubber is applied. Can be prevented from hanging. As a result, the pressure of the fluid in the fixed casing 20 does not affect the tightening allowance between the inner surface 14e of the stator 14 and the outer surface 13c of the rotor 13 due to the compression of the stator 14, and is regulated to a predetermined tightening allowance. can do. As a result, it is possible to accurately manage the fluid discharge flow rate.

  Next, a uniaxial eccentric screw pump 41 according to a third embodiment of the present invention will be described with reference to FIG. The difference between the third embodiment shown in FIG. 5 and the second embodiment shown in FIG. 4 is that the moving mechanisms 42 and 26 are different. In the moving mechanism 26 of the second embodiment shown in FIG. 4, the stator 14 is relatively centered with respect to the rotor 13 by rotating the moving casing 21 provided with the stator 14 in the screw direction of the screw portion 27. In contrast to the movement mechanism 42 of the third embodiment shown in FIG. 5, the rotor 13 is moved relative to the stator 14 with respect to the central axis 30 of the inner hole 14 a of the stator 14. It is designed to move forward and backward relative to the direction. Other than this, the second embodiment is the same as the second embodiment, and the equivalent parts are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 5, the stator 14 attached in the outer cylinder portion 39 is mounted and fixed in a space formed inside the distal end portion of the fixed casing 20 and inside the end stud 32.

  As shown in FIG. 5, the moving mechanism 42 includes an input shaft 18, a moving shaft 43, a rotational power transmission unit 44, a moving operation unit 45, a first moving screw unit 46, and a second moving screw unit 47.

  The input shaft 18 is rotatable via two bearings 19 and 19 and is provided inside the fixed casing 20 so as not to move in the axial direction. The base end portion of the input shaft 18 is connected to a rotating shaft of a rotor driving unit (not shown).

  The moving shaft 43 is for transmitting the rotation of the input shaft 18 to the rotor 13, and is coupled to the pin receiving portion 17 of the connecting portion 16. The moving shaft 43 is inserted into a sliding hole 48 whose base end is formed at the distal end of the input shaft 18, and is slidable along the axial direction in the sliding hole 48. . The moving shaft 43 is connected to the input shaft 18 via a key 49 and a key groove 50 so that the rotation of the input shaft 18 can be transmitted to the rotor 13.

  In this way, the rotational power transmission unit 44 connects the moving shaft 43 and the input shaft 18 to each other. According to the rotational power transmission unit 44, the moving shaft 43 can be connected to the input shaft 18 so as to extend and contract in the axial direction, and the rotation of the input shaft 18 can be transmitted to the moving shaft 43.

  The movement operation unit 45 is a shaft-like body formed to a predetermined length, and is rotatably inserted into an insertion hole 51 formed in the axial direction of the input shaft 18. The moving operation portion 45 has a tip portion screwed to the moving shaft 43 via the first moving screw portion 46, and a portion slightly behind from the tip portion connects the second moving screw portion 47. Via the input shaft 18.

  As shown in FIG. 5, the first moving screw portion 46 has a male screw portion formed in the moving operation portion 45 and a female screw portion formed in the moving shaft 43. The second moving screw portion 47 has a male screw portion formed in the moving operation portion 45 and a female screw portion formed in the input shaft 18. The first moving screw portion 46 is a right-hand screw, the second moving screw portion 47 is a left-hand screw, and the two screw portions 46 and 47 are formed with screws in opposite directions.

  According to the first and second moving screw portions 46 and 47, the moving operation unit 45 is rotated in a predetermined direction or the opposite direction, thereby moving the moving shaft 43 from the distal end portion of the moving operation unit 45 in the extending direction or the shortening direction. Can be moved. As a result, the rotor 13 can be moved back and forth in the direction of the central axis 30, and the tightening margin between the outer surface 13c of the rotor 13 and the inner surface 14e of the stator 14 can be adjusted.

  Further, as shown in FIG. 5, a male screw portion 52 is formed at the base end portion (the right end portion shown in FIG. 5) of the movement operation portion 45, and a lock nut 53 is screwed to the male screw portion 52. .

  Next, a procedure for operating the moving mechanism 42 configured as described above to move the rotor 13 forward and backward relative to the stator 14 in the direction of the central axis 30 will be described with reference to FIG. . The purpose of moving the rotor 13 in the direction of the central axis 30 relative to the stator 14 is to adjust the tightening margin between the rotor 13 and the stator 14 to an appropriate size as described in the first embodiment. Because.

  First, the lock nut 53 shown in FIG. 5 is loosened, and the moving operation unit 45 is rotated in a predetermined direction or the opposite direction. As a result, the rotor 13 can be moved forward and backward relative to the stator 14 by a predetermined dimension relatively easily in the direction of the central axis 30 of the inner hole 14 a of the stator 14. The cost can be easily adjusted. After that, the lock nut 53 is tightened to fix the moving operation unit 45 to the input shaft 18. This completes the adjustment of the tightening allowance.

  When the moving mechanism 42 is configured as shown in FIG. 5, the end operation part 32 and the input shaft 18 coupled to the stator 14 are not moved or moved forward and backward in the direction of the central axis 30 of the inner hole 14a. By rotating 45 in the screw direction of the first and second moving screw portions 46 and 47, the rotor 13 is moved forward and backward relative to the stator 14 in the direction of the central axis 30 of the inner hole 14a. Can do. That is, for example, the end stud 32 may be connected to a fixed pipe, or the input shaft 18 may be coupled to the rotating shaft of the rotor drive unit. In such a case, the end stud coupled to the stator 14 may be used. 32 and the input shaft 18 may not be rotated or moved in the direction of the central axis, but the tightening allowance of the rotor 13 and the stator 14 can be easily adjusted without rotating the end stud 32 and the input shaft 18. Can be done.

  Next, a uniaxial eccentric screw pump 55 according to a fourth embodiment of the present invention will be described with reference to FIGS. The difference between the fourth embodiment shown in FIGS. 6A and 6B and the second embodiment shown in FIG. 4 is that the moving mechanisms 56 and 26 are different. In the moving mechanism 26 of the second embodiment shown in FIG. 4, the stator 14 is relatively centered with respect to the rotor 13 by rotating the moving casing 21 provided with the stator 14 in the screw direction of the screw portion 27. Whereas the moving mechanism 56 according to the fourth embodiment shown in FIGS. 6A and 6B is moved forward and backward in the direction of the shaft 30, the end stud fixedly attached to the fixed casing 20 is attached. 32 and the stator 14 accommodated in the inner space formed by the fixed casing 20, relative to the rotor 13 in this space, in the direction of the central axis 30 of the inner hole 14 a of the stator 14. It is designed to move forward and backward. Other than this, the second embodiment is the same as the second embodiment, and the equivalent parts are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIGS. 6A and 6B, the end stud 32 is formed in a cup shape and fastened to the fixed casing 20 with a bolt 57. The stator 14 mounted in the outer cylinder portion 39 is disposed in an inner space formed by the end stud 32 and the fixed casing 20, and the stator 14 is located with respect to the rotor 13 in this space. The inner hole 14a is configured to be movable back and forth relatively in the direction of the central axis 30.

  The moving mechanism 56 is for moving the stator 14 configured in this way forward and backward in the direction of the central axis 30, and as shown in FIGS. 6A and 6B, the protrusion 58 and the adjusting bolt 59. It has.

  The protrusion 58 protrudes from the outer surface of the outer cylinder portion 39 and protrudes into a notch 60 formed at the front end opening edge of the fixed casing 20. The opening of the notch 60 is closed by a flange-shaped edge 61 provided on the end stud 32.

  The adjustment bolt 59 is rotatably inserted into an insertion hole 62 formed in the edge portion 61 and is screwed into a female screw portion 63 formed in the protrusion 58. The adjustment bolt 59 is parallel to the central axis 30 of the inner hole 14 a of the stator 14. By rotating the adjustment bolt 59, the projection 58, the outer cylinder portion 39 coupled to the projection 58, and The stator 14 mounted in the outer cylindrical portion 39 can be moved back and forth in the direction of the central axis 30 of the inner hole 14a, whereby the outer surface 13c of the rotor 13 and the inner surface 14e of the stator 14 are tightened. You can adjust the bill.

  Moreover, 64 shown to Fig.6 (a), (b) is a lock bolt. The lock bolt 64 is screwed into a female screw portion 65 formed on the edge portion 61, and the tip thereof is in contact with the side surface of the protrusion 58. The stator 14 can be fixed at a desired tightening margin position by the lock bolt 64 and the adjustment bolt 59.

  6A and 6B, the inner space formed by the end stud 32 and the fixed casing 20 and the notch 60 are arranged in the direction of the central axis 30 of the inner hole 14a. It is formed in a size and shape that can be moved forward and backward within a predetermined range. The rotation of the stator 14 about the central axis 30 is restricted by the protrusion 58 coming into contact with the inner surface of the notch 60.

  In order to seal the space in the end stud 32, an O-ring 66 is mounted between the inner peripheral surface of the end stud 32 and the outer peripheral surface of the outer cylindrical portion 39. In order to seal the space in the fixed casing 20, an O-ring 66 is mounted between the inner peripheral surface of the fixed casing 20 and the outer peripheral surface of the outer cylindrical portion 39. And as shown in FIG.6 (b), the scale 67 is displayed on the surface of the part in which the notch part 60 of the fixed casing 20 is formed. An arrow 68 for indicating the position of the stator 14 is displayed on the surface of the protrusion 58. The arrow 68 and the scale 67 can indicate the position of the stator 14 with respect to the rotor 13.

  Next, the procedure for moving the stator 14 in the direction of the central axis 30 relative to the rotor 13 by operating the moving mechanism 56 configured as described above will be described with reference to FIGS. Will be described with reference to FIG. The purpose of moving the stator 14 forward and backward relative to the rotor 13 in the direction of the central axis 30 is to adjust the tightening margin between the rotor 13 and the stator 14 to an appropriate size as described in the first embodiment. It is to do.

  For example, when increasing the tightening allowance between the rotor 13 and the stator 14, the adjustment bolt 59 shown in FIGS. 6A and 6B is rotated in a predetermined direction so that the inner surface 14 e of the stator 14 becomes the outer surface 13 c of the rotor 13. Move in the direction of pressing. As a result, the stator 14 can be moved forward and backward relative to the rotor 13 by a predetermined dimension relatively easily in the direction of the central axis 30 of the inner hole 14 a of the stator 14. Adjustment to increase the allowance can be easily performed. Thereafter, the lock bolt 64 is tightened to fix the stator 14 to the fixed casing 20. This completes the adjustment of the tightening allowance.

  In order to reduce the tightening margin between the rotor 13 and the stator 14, the lock bolt 64 is rotated in a predetermined direction, and the tip of the lock bolt 64 is pulled away from the side surface of the protrusion 58. Next, the adjustment bolt 59 is rotated in the direction opposite to the predetermined direction to move the inner surface 14 e of the stator 14 in a direction to separate from the outer surface 13 c of the rotor 13. As a result, the stator 14 can be moved forward and backward relative to the rotor 13 by a predetermined dimension relatively easily in the direction of the central axis 30 of the inner hole 14 a of the stator 14. Adjustment to reduce the allowance can be easily performed. Thereafter, the lock bolt 64 is tightened to fix the stator 14 to the fixed casing 20. This completes the adjustment of the tightening allowance.

  If the moving mechanism 56 is configured as shown in FIG. 6, for example, the rotor 13 may be connected to the rotating shaft of the rotor driving unit, or the end stud 32 may be connected to a fixed pipe. Without moving or rotating the rotor 13 and the end stud 32 in the direction of the central axis 30 of the inner hole 14a of the stator 14, the tightening allowance of the rotor 13 and the stator 14 can be adjusted easily.

  Next, a uniaxial eccentric screw pump 70 according to a fifth embodiment of the present invention will be described with reference to FIG. The difference between the fifth embodiment shown in FIG. 7 and the third embodiment shown in FIG. 5 is that the moving mechanisms 71 and 42 are different. In the moving mechanism 42 of the third embodiment shown in FIG. 5, the direction of the central axis 30 of the inner hole 14 a of the stator 14 with respect to the rotor 13 with respect to the stator 14 by the operator turning the moving operation unit 45 by hand. In the moving mechanism 71 of the fifth embodiment shown in FIG. 7, the rotor 13 is moved relative to the stator 14 in the direction of the central axis 30 of the inner hole 14 a of the stator 14. The rotor 13 is urged in the forward direction by the urging means 72 in a state in which it can be moved forward and backward relatively. Other than this, the third embodiment is the same as the third embodiment, and the same parts are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 7, the stator 14 attached in the outer cylinder portion 39 is mounted and fixed in a space formed on the inner side of the distal end portion of the fixed casing 20 and the inner side of the end stud 32.

  As shown in FIG. 7, the moving mechanism 71 includes an input shaft 18, a moving shaft 43, a rotational power transmission unit 44, and an urging unit 72.

  The input shaft 18 is rotatable via two bearings 19 and is provided inside the fixed casing 20 so as not to move in the axial direction. The base end portion of the input shaft 18 is connected to a rotating shaft of a rotor driving unit (not shown).

  The moving shaft 43 is for transmitting the rotation of the input shaft 18 to the rotor 13, and is coupled to the pin receiving portion 17 of the connecting portion 16. The moving shaft 43 is inserted into a sliding hole 48 whose base end is formed at the distal end of the input shaft 18, and is slidable along the axial direction in the sliding hole 48. . The moving shaft 43 is connected to the input shaft 18 via a key 49 and a key groove 50 so that the rotation of the input shaft 18 can be transmitted to the rotor 13.

  In this way, the rotational power transmission unit 44 connects the moving shaft 43 and the input shaft 18 to each other. According to the rotational power transmission unit 44, the moving shaft 43 can be connected to the input shaft 18 so as to extend and contract in the axial direction, and the rotation of the input shaft 18 can be transmitted to the moving shaft 43.

  The biasing means 72 is, for example, a compression coil spring, and the distal end portion of the input shaft 18 is inserted inside the biasing means 72. In a compressed state, the urging means 72 abuts on the front end surface of the pin receiving portion 17 of the connecting portion 16, and the rear end portion of the urging means 72 abuts on the front end surface of the mechanical seal 34. ing. According to the biasing means 72, the moving shaft 43 provided so as to be movable back and forth in the direction of the central axis 30 of the inner hole 14a (the axial direction of the input shaft 18), the connecting portion 16 connected thereto, the connecting shaft 15, and The rotor 13 can be biased in the extending direction in which the outer surface 13 c of the rotor 13 is pressed against the inner surface 14 e of the stator 14.

  Next, the operation of the moving mechanism 71 configured as described above will be described with reference to FIG. Since the urging means 72 urges the outer surface 13c of the rotor 13 in a direction to press the inner surface 14e of the stator 14, the outer surface 13c of the rotor 13 is pressed against the inner surface 14e of the stator 14 with a predetermined force. It is in a state. Then, for example, due to temperature changes of the stator 14 and the rotor 13 or due to wear of the stator 14 or the rotor 13, these stators 14 or rotors are increased or decreased in a direction in which the tightening margin of the contact surface between the rotor 13 and the stator 14 increases or decreases. When 13 is deformed (expanded or contracted), the rotor 13 can move in the axial direction to absorb the deformation. Thereby, the tightening allowance between the outer surface 13c of the rotor 13 and the inner surface 14e of the stator 14 can be automatically adjusted so as to be maintained at a substantially predetermined size.

  For example, the stator 14 and the rotor 13 expand (or contract) due to a temperature change of the stator 14 and the rotor 13, and the stator 14 in a direction in which the tightening margin of the contact surface between the stator 14 and the rotor 13 increases (or decreases). Alternatively, when the rotor 13 is deformed, the rotor 13 can automatically move in the direction of the central axis 30 that absorbs the deformation, that is, in the right direction (or left direction) in FIG.

  Further, since the biasing means 72 is a compression coil spring, it has a relatively simple structure, and the rotor 13 is moved against the input shaft 18 by the spring force of the compression coil spring without using external power. Can be urged in the extending direction.

  However, although the biasing means 72 shown in FIG. 7 is a compression coil spring, instead of this, for example, a compression disc spring having a bimetal structure can be used alone or in a stacked manner. This bimetal structure is configured such that the compression disc spring is shortened as the temperature rises, and the compressed disc spring is elongated as the temperature falls.

  Now, when the temperature of the stator 14 and the rotor 13 changes and the stator 14 or the rotor 13 is deformed, the allowance for the contact surface between the rotor 13 and the stator 14 becomes larger or smaller. At this time, the urging means 72 urges the outer surface 13c of the rotor 13 against the inner surface 14e of the stator 14 by the spring force, and therefore the rotor 13 has a large tightening margin on its contact surface. It can move in the direction of absorbing the decrease (the direction of the central axis 30). At this time, the compression disc spring, which is the urging means 72, is compressed or extended, so that the force by which the urging means 72 presses the outer surface 13c of the rotor 13 against the inner surface 14e of the stator 14 changes. Can be suppressed or eliminated by the compression disc spring having a bimetal structure being shortened or elongated in accordance with the temperature change. As a result, regardless of temperature changes of the stator 14 and the rotor 13, the tightening margin of the contact surface between the rotor 13 and the stator 14 can be automatically adjusted so as to be held at a predetermined size with relatively high accuracy. it can.

  Next, a uniaxial eccentric screw pump 74 according to a sixth embodiment of the present invention will be described with reference to FIG. The difference between the sixth embodiment shown in FIG. 8 and the fifth embodiment shown in FIG. 7 is that the moving shaft 43 is connected to the connecting shaft 15 via the connecting portion 16 in the fifth embodiment shown in FIG. In contrast, in the sixth embodiment shown in FIG. 8, the moving shaft 43 is connected to the connecting shaft 15 via the flexible rod portion 75. Other than this, it is the same as that of the fifth embodiment, and the equivalent parts are denoted by the same reference numerals, and the description thereof is omitted.

  The flexible rod portion 75 can transmit the rotation of the input shaft 18 to the rotor 13. The rotor 13 revolves around the central axis 30 of the stator inner hole 14a while rotating (planetary rotational movement). The flexible rod portion 75 bends (bends) so that the rotor 13 revolves. I can do it.

  In the conventional single-shaft eccentric screw pump, the rotor 2 and the input shaft 11 are connected to each other via a flexible rod instead of the connecting shaft 10 and the two universal joints 9 and 9 shown in FIG. There is a type that makes a revolving motion. In such a type, since the central axis of the rotor 2 and the input shaft 11 are eccentric in parallel with each other, they are connected to each other. The deformation reaction force may adversely affect the contact between the inner surface 14e of the stator 3 and the outer surface 13c of the rotor 2. In order to avoid this adverse effect, it is necessary to use a long flexible rod.

  On the other hand, in the uniaxial eccentric screw pump 74 shown in FIG. 8, the central axis 31 of the rotor 13 and the central axis 30 of the stator 14 only need to have a positional relationship of only the deflection angle 91, and the deformation of the flexible rod portion 75 is not necessary. Compared with the deformation of the flexible rod used in the conventional pump, it is extremely small and simple, and the reaction force of the deformation is small. Therefore, the relatively short flexible rod part 75 can be used.

  In this way, by using the flexible rod portion 75 instead of the connecting portion 16, the number of parts can be reduced and the cost can be reduced. Further, the length of the uniaxial eccentric screw pump 74 can be reduced. Can be shortened by the amount of the connecting portion 16.

  Next, in the uniaxial eccentric screw pump 12 of each of the first to fifth embodiments, the force acting on the rotor 13 will be described with reference to FIG. As shown in FIG. 1, since the rotor 13 and the input shaft 18 are connected to each other via one connecting portion 16, when the first opening 23 is used as a discharge port, The pressure of the fluid in one opening 23 acts as a force 77 that presses the rotor 13 toward the connecting portion 16, and this force 77 causes the rotor 13 to expand the rear end portion 14 b of the inner hole 14 a of the stator 14. Since it does not work, the inner surface 14e of the rear end portion 14b of the stator 14 is not subjected to partial wear, and the wear of the stator 14 can be suppressed as compared with the conventional case.

  That is, according to the conventional single-shaft eccentric screw pump 1, for example, as shown in FIG. 11B, the rotor 2 and the input shaft 11 are connected to each other via two universal joints 9 and 9. The pressure of the fluid in the discharge port 5 acts as a force 78 in a direction toward the rotor 2 toward the universal joint 9, the connecting shaft 10, and the universal joint 9, and this force 78 causes the rotor 2 to have an inner hole 3 a of the stator 3. It is decomposed into a first component force 78a that works to spread the rear end portion of the head and a second component force 78b in the direction toward the input shaft 11. The force acting so that the rotor 2 expands the rear end portion of the inner hole 3 a of the stator 3 is a factor that causes the stator 14 to wear.

  Next, the configuration of the rotor 13 of each of the above embodiments will be described with reference to FIGS. As shown in FIGS. 9A to 9C, the rotor 13 has an outer diameter that decreases from the rear end portion 13a toward the front end portion 13b. For example, when the rotor 13 is manufactured by molding, It is easy to remove or remove from a mold or the like, and can be manufactured using various conventionally known molding methods.

  The rotor 13 shown in FIG. 9A has a hollow structure and can be reduced in weight. The material can be made of metal, synthetic resin, glass, ceramic or the like. As a production method, a molding method such as spinning, pressing, bulge, blow or the like can be used.

  The rotor 13 shown in FIG. 9B is obtained by coating the surface of the core body 80 with a covering body 81 having a predetermined thickness. Since the covering body 81 is formed in a tapered shape, it can be attached to and detached from the core body 80. When the covering 81 is worn by use, the covering 81 can be repaired and used or replaced.

  The core body 80 can be used continuously, and the material thereof can be made of metal, synthetic resin, or the like. The material of the covering 81 is metal, synthetic rubber, synthetic resin, or the like. When the cover 81 is made of metal, in order to prevent the cover 81 from coming off the core 80, for example, the surface of the core 80 is coated with a synthetic rubber or the like, or the core 80 is made by the elastic force of the cover 81. Can be gripped.

  The rotor 13 shown in FIG. 9C has a solid structure, and the material is metal, synthetic resin, glass, ceramic, or the like. As a production method, cutting, forging, casting, injection molding, or the like can be used.

  Next, the configuration of the stator 14 of each of the above embodiments will be described with reference to FIGS.

  The stator 14 shown in FIG. 10A has a stator main body 83 mounted in an outer cylindrical portion 82 having an inner peripheral surface formed in a tapered shape. The end portion 82a having the larger thickness of the outer cylindrical portion 82 is arranged so as to correspond to the end portion having the smaller inner diameter of the semicircular portion in the cross section perpendicular to the central axis constituting the inner hole 14a of the stator 14. Therefore, the thickness between both end portions of the stator body 83 can be made substantially constant. As a result, the amount of expansion and contraction due to temperature change at each portion in the length direction of the stator body 83 can be kept substantially constant. The material of the outer cylinder portion 82 is, for example, metal or ceramic having a relatively small coefficient of thermal expansion. The material of the stator main body 83 is, for example, synthetic rubber or synthetic resin having a thermal expansion coefficient larger than that of the outer cylinder portion 82, so that elastic deformation of the contact portion with the rotor can be allowed.

  And since the inner peripheral surface of the outer cylinder part 82 is formed in the taper shape, the attachment / detachment of the stator main body 83 with respect to this outer cylinder part 82 can be performed easily. Therefore, the stator main body 83 or the outer cylindrical portion 82 can be easily replaced, and disassembly and cleaning can be easily performed.

  Further, when the outer peripheral surface of the outer cylinder part 82 is formed in a tapered shape, the stator 14 including the outer cylinder part 82 can be easily attached to and detached from, for example, the movable casing 21 shown in FIG. As a result, the stator main body 83 or the outer cylindrical portion 82 can be easily replaced, and disassembly and cleaning can be easily performed.

  Similarly, by forming the outer peripheral surface of each stator 14 shown in FIGS. 10B to 10E in a tapered shape, it can be easily attached to and detached from the movable casing 21.

  The stator 14 shown in FIG. 10B has a stator body 85 mounted in a cylindrical outer cylinder portion 84.

  The stator 14 shown in FIG. 10C has a covering portion 87 formed at a constant thickness on the inner peripheral surface of the inner hole 86a of the stator body 86, and the inner portion 14a of the stator 14 is formed by the covering portion 87. Is formed. The material of the stator body 86 is, for example, metal or ceramic having a relatively small coefficient of thermal expansion, and the material of the covering portion 87 is, for example, synthetic rubber or synthetic resin having a coefficient of thermal expansion greater than that of the stator body 86.

  According to the stator 14, by forming the stator body 86 with a material having a relatively small thermal expansion coefficient, expansion and contraction due to temperature changes of the stator 14 can be reduced, and the outer surface 13 c of the rotor 13 and the stator 14 can be reduced. The sealing property of the space 25 formed by the inner surface 14e can be ensured.

  The stator 14 shown in FIG. 10 (d) has a first covering portion 89 formed on the inner surface 14e of the inner hole 88a of the stator body 88, and a second covering portion 90 formed on the inner surface 14e. It is formed with a thickness. An inner hole 14 a of the stator 14 is formed by the second covering portion 90. The materials of the stator body 88 and the second covering portion 90 are the same as those of the stator body 86 and the covering portion 87 shown in FIG. The first covering portion 89 is an adhesive layer for bonding the second covering portion 90 to the inner peripheral surface of the inner hole 88 a of the stator body 88. This adhesive layer can also be applied to the bonding between the outer cylindrical portion of the stator 14 and the stator body shown in FIGS. 10 (a) and 10 (b).

  The stator 14 shown in FIG. 10 (e) is formed of a single material, and the material is synthetic rubber, synthetic resin, metal, glass, ceramic, or the like.

  However, in the moving mechanism 26 of the first and second embodiments shown in FIGS. 1 and 4, the moving casing 21 is provided with the male screw portion 27a, and the fixed casing 20 is provided with the female screw portion 27b. The casing 21 may be provided with the female screw portion 27b and the fixed casing 20 may be provided with the male screw portion 27a, and both may be screwed together.

  In the moving mechanism 26 and the like of the first to fourth embodiments shown in FIG. 1 and the like, the outer surface 13c of the rotor 13 and the inner surface 14e of the stator 14 are ejected when a liquid having a relatively high temperature (or low temperature) is discharged. The outer surface 13c of the rotor 13 and the inner surface 14e of the stator 14 are separated (or approached) in advance or each time so that the predetermined tightening allowance is obtained when the tightening allowance is large (or small). However, instead of this, the stator 14 is moved relative to the rotor 13. Instead of this, the gap between the outer surface 13 c of the rotor 13 and the inner surface 14 e of the stator 14 is set in advance or so as to have a predetermined dimension. The rotor 13 may be moved forward and backward relative to the stator 14 each time.

  In short, in each of the above embodiments, as shown in FIG. 1 and the like, the rotor 13 is rotated in a state where the inner surface 14e of the stator 14 and the outer surface 13c of the rotor 13 are in contact with each other with an appropriate tightening margin (pressure). However, instead of this, the rotor 13 can rotate relative to the stator 14 with the inner surface 14e of the stator 14 and the outer surface 13c of the rotor 13 facing each other with a slight gap. be able to.

  Further, in each of the above embodiments, as shown in FIG. 1 and the like, the stator 14 is fixed and the rotor 13 is rotated to discharge the fluid. However, in addition to this, both the rotor 13 and the stator 14 are discharged. You may make it discharge a fluid by rotating. Alternatively, the fluid may be discharged by fixing the rotor 13 and rotating the stator 14.

  Further, in the uniaxial eccentric screw pump 12 or the like according to each of the above-described embodiments shown in FIG. 1 and the like, the stator 14 has two female screw-type inner holes 14a, and the cross-sectional shape of the inner hole 14a is oval. The rotor 13 is formed in a single male screw type, the cross-sectional shape of the rotor 13 is circular, and the pitch ratio of the rotor 13 and the inner hole 14a is 1: 2. It has a female screw type inner hole, the cross-sectional shape of the inner hole is an approximately triangular shape with three corners being arcs, and the rotor is formed into two male screw types, and the rotor cross-sectional shape is substantially elliptical. The ratio of the rotor and inner hole pitch may be 2 to 3. Even in this case, the rotor and the stator have a relatively simple shape, and therefore can be formed with relatively high dimensional accuracy. Therefore, a uniaxial eccentric screw pump having the same operation and effect as the above embodiment can be provided.

  And in 3rd Embodiment shown in FIG. 5, the movement operation part 45 is engaged with the input shaft 18 via the 2nd moving screw part 47 so that rotation is possible, and the rotor 13 is made to center-axis 30 direction. However, instead of this, the convex portion provided on one of the outer surface of the moving operation unit 45 and the inner surface of the input shaft 18 is engaged with the concave portion provided on the other side, thereby moving the configuration. It is good also as a structure which can engage the operation part 45 with respect to the input shaft 18, and can move the rotor 13 to the center axis | shaft 30 direction.

  In the first embodiment shown in FIG. 1, the rotor 13 and the input shaft 18 are connected to each other via the connecting shaft 15 and the connecting portion 16. Instead, a flexible rod portion (not shown) is used. Both may be connected to each other. If it does in this way, it can constitute so that both or any one of flexible body part 14d of stator 14 and stator main-body part 14h may change so that a deformation of a flexible rod part may be decreased. Accordingly, a relatively short flexible rod portion can be used, and the rotor 13 can be smoothly rotated relative to the stator 14 with relatively small power.

  Further, in the first embodiment shown in FIG. 1, the moving casing 21 and the fixed casing 20 are connected to each other via the moving mechanism 26. Instead, the moving mechanism 26 is omitted and the moving casing 21 is moved. The casing 21 and the fixed casing 20 may be fixedly coupled to each other.

  As described above, the uniaxial eccentric screw pump according to the present invention has a predetermined discharge without replacing the rotor or the stator even when the volume of the rotor and the stator is changed due to a temperature change or when the rotor and the stator are worn. It has an excellent effect of being able to discharge fluid at a flow rate, and is suitable for application to such a uniaxial eccentric screw pump.

It is a longitudinal section showing a uniaxial eccentric screw pump concerning a 1st embodiment of this invention. It is a perspective view which shows the rotor and stator of the uniaxial eccentric screw pump which concern on the same 1st Embodiment, (a) is an expansion perspective view of a rotor, (b) is a partial expansion perspective view which shows the front-end | tip part of a stator, (c). FIG. 3 is a partially enlarged perspective view showing a rear end portion of a stator. It is a partial expanded longitudinal cross-sectional view which shows the rotor and stator of the uniaxial eccentric screw pump which concern on the 1st Embodiment. It is a longitudinal cross-sectional view which shows the uniaxial eccentric screw pump which concerns on 2nd Embodiment of the invention. It is a longitudinal cross-sectional view which shows the uniaxial eccentric screw pump which concerns on 3rd Embodiment of the same invention. (A) is a longitudinal cross-sectional view which shows the uniaxial eccentric screw pump which concerns on 4th Embodiment of the invention, (b) is a partial top view which shows the moving mechanism of the uniaxial eccentric screw pump shown to Fig.6 (a). It is a longitudinal section showing a uniaxial eccentric screw pump concerning a 5th embodiment of the invention. It is a longitudinal section showing a uniaxial eccentric screw pump concerning a 6th embodiment of the invention. It is a figure which shows the modification of the rotor of the uniaxial eccentric screw pump which concerns on each embodiment, (a) And (b) is a longitudinal cross-sectional view, (c) is a fragmentary sectional view. (A)-(e) is a longitudinal cross-sectional view which shows the modification of the stator of the uniaxial eccentric screw pump which concerns on each embodiment. It is a figure which shows the conventional uniaxial eccentric screw pump, (a) is a longitudinal cross-sectional view, (b) is a schematic diagram which shows the force which acts on a rotor and a connection shaft.

Explanation of symbols

12, 38, 41, 55, 70, 74 Uniaxial eccentric screw pump 13 Rotor 13a Rear end portion of rotor 13b Front end portion of rotor 13c Outer surface of rotor 14 Stator 14a Inner hole of stator 14b Rear end portion of stator 14c Front end portion of stator 14d Flexible body portion 14e Stator inner surface 14f Stator flange portion 14g Stator end surface 14h Stator main body portion 15 Connection shaft 16 Connection portion 16a Insertion hole 16b Connection pin 17 Pin receiving portion 18 Input shaft 19 Bearing 20 Fixed casing 21 Moving casing 22 Clearance 23 First opening 24 Second opening 25 Space 26, 42, 56, 71 Moving mechanism 27 Screw part 27a Male thread part 27b, 63, 65 Female thread part 28, 53 Lock nut 29, 66 O-ring 30 Center axis of stator 31 Center axis of rotor 32 Threaded stud 33 Bulkhead part 34 Mechanical seal 35 Discharge hole 36 Liquid reservoir part 39 Outer cylinder part 43 Moving shaft 44 Rotational power transmission part 45 Moving operation part 46 First moving screw part 47 Second moving screw part 48 Sliding hole 49 Key 50 Key groove 51 Insertion hole 52 Male thread portion 57 Bolt 58 Projection 59 Adjustment bolt 60 Notch portion 61 Edge portion 62 Insertion hole 64 Lock bolt 67 Scale 68 Arrow 72 Energizing means 75 Flexible rod portion 77, 78 Force 78a First component force 78b Second component force 80 Core body 81 Cover body 82, 84 Outer tube portion 82a End portion 83, 85, 86, 88 Stator body 86a, 88a Inner hole 87 Cover portion 89 First cover portion 90 Second cover portion 91 Deflection angle O Intersection

Claims (14)

In the uniaxial eccentric screw pump in which the male screw type rotor is fitted into the inner hole of the female screw type stator, the rotor rotates relative to the stator, and the fluid can be discharged from the discharge port.
As the outer diameter of the rotor decreases and the inner diameter of the inner hole of the stator decreases as it goes from the corresponding one end to the other end of the stator and the stator ,
In a state where the rotor is fitted in the inner hole of the stator, the respective central axes of the rotor and the stator approach each other and cross each other from the other end side of the rotor toward the one end side. A uniaxial eccentric screw pump characterized by that. The cross-sectional area perpendicular to the central axis of the inner hole in the space formed between the outer surface of the rotor and the inner surface of the inner hole of the stator is substantially the same at any position of the central axis. The uniaxial eccentric screw pump according to claim 1 , wherein inner holes of the rotor and the stator are formed. The dimension of the space formed between the outer surface of the rotor and the inner surface of the inner hole of the stator is perpendicular to the central axis of the inner hole and passes through the central axis of the rotor. 3. The uniaxial eccentric screw pump according to claim 2 , wherein the uniaxial eccentric screw pump is formed so as to increase in size from one end portion to the other end portion of the stator. The space formed between the outer surface of the rotor and the inner surface of the inner hole of the stator has a cross-sectional area perpendicular to the central axis of the inner hole from the corresponding one end to the other end of the rotor and the stator. The single-shaft eccentric screw pump according to claim 1 , wherein inner holes of the rotor and the stator are formed so as to become smaller toward the portion. The uniaxial eccentric screw according to any one of claims 1 to 4 , further comprising a moving mechanism for moving the stator relative to the rotor in a direction of a central axis of an inner hole of the stator. pump. The moving mechanism includes a moving casing in which the stator is provided, a fixed casing in which the rotor is provided, and a screw portion that connects the moving casing and the fixed casing to each other.
By rotating the movable casing in the screw direction of the threaded portion, the stator can be moved relative to the rotor in the direction of the central axis of the inner hole. The uniaxial eccentric screw pump according to claim 5 . The moving mechanism includes a fixed-side input shaft for transmitting rotational power to the rotor, a moving shaft connected to the rotor and transmitting rotation of the input shaft to the rotor, and the moving shaft as the input The shaft is connected to a shaft so as to be extendable in the axial direction, and is inserted into a rotational power transmission portion for transmitting the rotation of the input shaft to the moving shaft, and an insertion hole formed in the input shaft in the axial direction. A moving operation unit coupled to the moving shaft via a screw part,
By rotating the moving operation portion in the screw direction of the screw portion, the rotor can be moved relative to the stator in the direction of the central axis of the inner hole. The uniaxial eccentric screw pump according to claim 5 . The moving mechanism is configured such that the stator is movable relative to a fixed casing in a direction of a central axis of the inner hole, and one of a protrusion provided on the stator and an edge formed on the fixed casing. By rotating an adjustment bolt that is inserted into and screwed into the other in the screw direction, the stator can be moved relative to the rotor in the direction of the central axis of the inner hole. 6. The single-shaft eccentric screw pump according to claim 5, wherein: The moving mechanism includes a fixed-side input shaft for transmitting rotational power to the rotor, a moving shaft connected to the rotor and transmitting rotation of the input shaft to the rotor, and the moving shaft as the input A rotational power transmission portion for transmitting the rotation of the input shaft to the moving shaft and an urging force for urging the rotor in the extension direction with respect to the input shaft. The uniaxial eccentric screw pump according to claim 5 , wherein the uniaxial eccentric screw pump is provided with a biasing means. The uniaxial eccentric screw pump according to claim 9 , wherein the biasing means is a compression spring. The biasing means is a compression spring and has a bimetal structure,
The single-shaft eccentric screw pump according to claim 9 , wherein the bimetal structure shortens the compression spring as the temperature rises, and extends the compression spring as the temperature falls. The single-shaft eccentric screw pump according to any one of claims 1 to 11 , wherein the stator is made of synthetic rubber or synthetic resin. The stator has an attachment part attached to the casing, and a flexible body part,
The uniaxial eccentric screw pump according to claim 12 , wherein the flexible body is deformable in a central axis direction of an inner hole of the stator. The stator has an attachment part attached to the casing, and a stator body part,
The uniaxial eccentric screw pump according to claim 12 , wherein the stator main body portion is deformable in a direction orthogonal to a central axis of an inner hole of the stator.

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