JP5771560B2 - Gear pump and refrigerator equipped with the same - Google Patents

Description

  The present invention relates to a gear pump and a refrigerator provided with the gear pump.

  As a background art in this technical field, there is Japanese Patent No. 3030202 (Patent Document 1). The drive gear and the driven gear of the gear pump described in this document 1 are solidly formed of resin.

  In Patent Document 2, the thrust surface (both sides) of the gear is provided with a tapered recess for preventing sinking of the gear tip at the time of molding, and a resin piece embedded in the recess Is installed to prevent the deterioration of pump performance due to burrs as well as improving production efficiency.

Japanese Patent No. 3030202 JP-A-7-127957

  However, in the configuration described in Patent Document 1, in order to form solidly, the time for injecting the liquid resin into the mold and the time until the resin is solidified and the temperature is lowered are prolonged, and the production efficiency is lowered.

  Also, in the vicinity of the injection point when the resin is injected into the mold (for example, the upper surface or the lower surface of the gear where the shaft hole is formed), protrusions, so-called burrs, remain after the molding is completed, resulting in individual differences in the gear, resulting in dimensional accuracy Decreases. Also, when this burr is finished, it is not completely flat and some steps remain. Due to this step, the center of gravity of the gear shifts, causing a whirling when the gear rotates, contacting the casing or the other gear and causing a reduction in suction capability and noise.

  In the configuration described in Patent Document 2, if a liquid such as water that is a transfer fluid flows into the concave portion of the gear, the liquid stays without being discharged. There is a risk of becoming. In addition, when a communication hole that connects the upper and lower surfaces of the gear is provided, the water in the gear recess is discharged, but since the gap between the gear and the casing is very small, the gap between the gear and the casing is affected by the surface tension. There is a risk that liquid will remain on the surface.

  Therefore, the present invention efficiently discharges the liquid that has entered the upper or lower surface of the gear when the gear rotates, thereby making it difficult for the liquid to be transferred to stay in the transfer path, and a gear pump excellent in hygiene and a refrigerator equipped with the gear pump. The purpose is to provide.

In the present invention, in order to solve the above-described problems, for example, means described in the claims are adopted. As an example, a drive gear that rotates about a vertical rotation axis by a drive source, a driven gear that meshes with the drive gear and rotates about a vertical rotation axis, and a pump in which the drive gear and the driven gear are arranged. In the gear pump provided with a chamber, the drive gear and the driven gear each have a communication hole communicating with the upper surface and the lower surface, and the drive gear includes a gear portion and an insertion hole for inserting the drive shaft. A cylindrical portion, and a connecting portion that connects the gear portion and the cylindrical portion, and the driven gear includes a gear portion, a cylindrical portion that includes an insertion hole through which the rotation support shaft is inserted, and the gear portion. A coupling portion that couples the cylindrical portion, and the coupling portions of the drive gear and the driven gear have slopes that decrease toward the drive shaft side and the rotation support shaft side, respectively, Follower Characterized by the discharge, respectively of the upper surface or the liquid that has entered the lower surface on the lower side or upper from the communication hole.

  ADVANTAGE OF THE INVENTION According to this invention, the liquid which entered into the gear upper surface or lower surface at the time of gear rotation is discharged | emitted efficiently, the liquid to transfer becomes difficult to stay in a transfer path | route, and the gear pump excellent in hygiene and a refrigerator provided with the same Can be provided.

1 is an external perspective view of a gear pump according to an embodiment of the present invention. It is an exploded perspective view of the whole gear pump concerning one embodiment of the present invention. It is principal part sectional drawing of the gear pump which concerns on one Embodiment of this invention. It is a longitudinal section of the whole gear pump concerning one embodiment of the present invention. It is a longitudinal cross-sectional view of the refrigerator main body which concerns on one Embodiment of this invention.

  Hereinafter, modes for carrying out the present invention will be described. In addition, the following is one Example in this invention, and this invention is not limited to this.

  FIG. 1 is an external perspective view of a gear pump according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the entire gear pump according to the embodiment of the present invention. FIG. 3 is a cross-sectional view of a main part of a gear pump according to an embodiment of the present invention. FIG. 4 is a longitudinal sectional view of the entire gear pump according to the embodiment of the present invention.

  First, the overall configuration of the gear pump will be described. The gear pump 1 includes a motor housing 4 in which a motor 2 as a driving source is housed, a lower casing 9 disposed on the motor housing 4, an upper casing 10 positioned on the lower casing 9, The overall appearance is constituted by the middle casing 11 disposed between the casing and the lower casing.

  The upper casing 10 is provided with a suction port 10a and a discharge port 10b on opposite sides of the case.

  A space defined by the upper casing 10 and the middle casing 11, a so-called pump chamber, communicates with the outside through a suction port 10 a and a discharge port 10 b, and inside the pair of drive gears 7 and a driven gear that mesh with each other. 8 is stored. The drive gear 7 is rotationally driven by the rotation of the motor 2 being reduced and transmitted by the reduction gears (the first reduction gear 3a and the second reduction gear 3b). The driven gear 8 meshes with the rotation of the drive gear 7 and rotates.

  The gear pump sucks a fluid (for example, a liquid such as water supplied to an ice tray to generate ice) from the suction port 10a by the rotation of the pair of drive gears 7 and the driven gear 8, and drives the drive gear 7 and the driven gear. 8 is a basic configuration in which pressure is fed in a space between each of the inter-tooth regions 7c, 8c and the inner peripheral wall 10e of the upper casing 10 and discharged from the discharge port 10b.

  Next, the assembly configuration and internal components of each casing will be further described. The motor housing part 4 has a bottomed hollow cylindrical shape, and its upper part is open. An engaging claw 4a is formed on at least a part of the open edge. The lower casing 9 has a function of partitioning the motor 2 storage space and the arrangement space of the reduction gear train (first reduction gear 3a, second reduction gear 3b), and has a bottomed hollow cylindrical shape with an O-shaped cross section. is there. The engaging claw 4a of the motor housing portion 4 is elastically engaged with the lower end portion of the lower casing 9, so that the motor housing portion 4 and the lower casing 9 are combined (see FIG. 4). A plurality of screw holes 17 are formed in the bottom surface of the lower casing 9. The motor 2 and the lower casing 9 are fixed by inserting the screw 16 into the screw hole 17.

  An output shaft 2 a is provided on the top of the motor 2. The output shaft 2a protrudes from the lower casing 9 upward (from the motor housing space to the reduction gear train arrangement space) through the output shaft communication hole 9e1 formed in the lower casing 9. Further, by providing the seal member 3c at the periphery of the output shaft communication hole 9e1, the liquid is prevented from flowing from the output shaft communication hole 9e1 into the motor storage portion 4. Furthermore, the edge part of the output-shaft communication hole 9e1 has the rising part 9e2 erected upward. Thereby, even if the sealing member 3c deteriorates and the sealing performance is lowered, the rising portion 9e2 prevents the liquid from flowing into the motor storage portion 4.

  At the upper end of the output shaft 2a (above the seal member 3 and the rising portion 9e2), a first reduction gear 3a is inserted through a central shaft hole so as to be rotationally driven integrally with the output shaft 2a. The second reduction gear 3 b that meshes with the first reduction gear 3 a is disposed in a space surrounded by the lower casing 9 and the middle casing 11. The drive shaft 5 is inserted through the central shaft hole of the second reduction gear 3b. The drive shaft 5 passes through a drive shaft insertion hole 11 e 1 formed in the middle casing 11 and reaches the inner surface of the upper surface wall of the upper casing 10. The lower end of the drive shaft 5 is supported by a drive shaft support portion 9 f provided in the lower casing 9. The upper end of the drive shaft 5 is supported by a drive shaft support portion 10 f provided in the upper casing 10. That is, the drive shaft 5 is pivotally supported at the lower end and the upper end thereof by the drive shaft support portion 9f and the drive shaft support portion 10f.

  A drive gear 7 is inserted through a drive shaft insertion hole 7 a formed in the cylindrical portion 7 f into a portion protruding upward from the middle casing 11 of the drive shaft 5. A driven gear 8 having the same pitch that meshes with the drive gear 7 is also provided along with the drive gear 7.

  A sealing member that prevents water and the like from entering the motor 2 via the drive shaft 5 around the drive shaft 5 (around the lower portion of the drive shaft insertion hole 11e1) on the lower surface of the middle casing 11 6 is provided.

  The driven gear 8 has a cylindrical portion 8f in the center, and the rotation support shaft 15 is inserted into a rotation support shaft insertion hole 8a formed in the cylinder portion 8f. The lower end of the rotation support shaft 15 is supported by a rotation support shaft lower end support portion 11 e 2 formed in the middle casing 11.

  Here, the cylindrical portion 8f has a bottomed hollow cylindrical shape whose upper end is closed by the rotation support shaft insertion hole upper end portion 8b. That is, the rotation support shaft 15 is in a so-called cantilever support state in which the lower end is supported and the upper end is a free end.

  On the outer periphery of the surface in contact with the middle casing 11 of the upper casing 10, an annular seal member 19 is disposed in a groove portion 10 g having a U-shaped cross section. Thereby, the outflow of the transfer fluid from the pump chamber (the space defined by the upper casing 10 and the middle casing 11) is suppressed.

  These parts are configured by combining an upper casing 10, a middle casing 11, and a lower casing 9. Specifically, the fastening holes 10c of the upper casing 10, the fastening holes 11c of the middle casing 11, and the fastening holes 9c of the lower casing 9 are provided at the four corners of the respective casings. It is located so as to correspond to each direction. Each casing is fastened with a fastening member (screw) so as to pass through a screw hole communicating vertically with the fastening hole 10c, the fastening hole 11c, and the fastening hole 9c.

  When the upper casing 10, the middle casing 11, and the lower casing 9 are fastened by the fastening member 12, it is necessary to adjust so that the positions of the fastening holes 10c, the fastening holes 11c, and the fastening holes 9c are at predetermined positions. In this embodiment, a plurality of engaging portions are provided for positioning of each fastening hole and improvement of assembly accuracy.

  Specifically, on the outer surface of the side wall of the upper casing 10 and between the one fastening hole 10c and the other fastening hole 10c, the upper first engaging part 10d1, the upper second engaging part 10d2, and the upper third engaging part. A joint portion 10d3 is formed. The upper first engaging portion 10d1, the upper second engaging portion 10d2, and the upper third engaging portion 10d3 are rectangular portions that extend vertically at predetermined intervals, respectively. It has a lower length that touches it.

  In addition, a rectangular middle first engaging portion 11d1 and a middle second engaging portion 11d2 extending vertically at predetermined intervals are formed on the outer surface of the side wall of the middle casing 11. The middle first engaging portion 11d1 is inserted between the upper first engaging portion 10d1 and the upper second engaging portion 10d2, and the middle second engaging portion 11d2 is connected to the upper second engaging portion 10d2 and the upper second engaging portion 10d2. The positional relationship is inserted between the three engaging portions 10d3.

  A rectangular lower engaging portion 9d1 that is inserted between the middle first engaging portion 11d1 and the middle second engaging portion 11d2 is formed on the outer surface of the side wall of the lower casing 9.

  In addition, each engaging part is each arrange | positioned symmetrically on one side and the other side across the surface which passes along the suction inlet 10a and the discharge outlet 10b.

  In this configuration, when the upper casing 10, the middle casing 11, and the lower casing 9 are assembled by engaging each engaging portion at a predetermined position, the engaging portion is visually recognized from the outside before and after the fastening member 12 is fastened. Is possible. Thereby, it can be visually confirmed whether there is an error in assembly.

  Furthermore, the upper second engaging portion 10d2 and the lower engaging portion 9d1 are arranged on the extension line in the vertical direction with a predetermined interval. When fastening with the fastening member 12, the seal member 3c disposed on the outer periphery of the lower surface of the upper casing is elastically deformed. In the case where the four corners are fastened with the fastening member 12, if the fastening force varies among the four corners, the sealing performance may be biased. In this embodiment, depending on the distance between the upper second engaging portion 10d2 and the lower engaging portion 9d1, the fastening force is appropriate or the surface passing through the suction port 10a and the discharge port 10b is separated. It can be confirmed whether the fastening force on one side and the other side is equal.

  Next, the suction-discharge process of the transfer fluid will be described. As shown in FIG. 3, when the drive gear 7 is rotationally driven in the r1 direction, the meshed driven gear 8 is also rotationally driven in the r2 direction. As a result, a pressure difference occurs between the suction side (suction port 10a) and the discharge side (discharge port 10b), and a transfer fluid (for example, a liquid such as water after a gas such as air is sucked in) from the suction port 10a. It is sucked into the pump chamber (in the direction of arrow a in FIG. 3). The transfer fluid sucked into the pump chamber is pumped to the discharge side in the space between the inter-tooth regions 7c and 8c of the drive gear 7 and the driven gear 8 and the inner peripheral wall 10e of the upper casing 10. Then, it is discharged after being transferred to the discharge port 10b (in the direction of arrow b in FIG. 3).

  Here, the drive shaft insertion hole 7 a of the drive gear 7 of the present embodiment is formed with a fitting dimension so as to rotate integrally with the drive shaft 5. Further, the drive shaft 5 is formed with a D-cut surface 5a, and a shape corresponding to the drive shaft insertion hole 7a is also formed. As a result, the driving force of the motor 2 is transmitted without loss through the gap between the drive shaft 5 and the drive shaft insertion hole 7a, and the suction-discharge efficiency is improved.

  A groove 18 is formed on the lower surface of the position where the drive gear 7 and the driven gear 8 are engaged. This is because when the volume of the transfer fluid sandwiched between the teeth of the drive gear 7 and the driven gear 8 fluctuates with the rotation of the gear, the liquid such as water, that is, the incompressible fluid is reduced in volume. Very high pressure. Also, if pressure fluctuations occur intermittently, the gears vibrate and cause noise. Furthermore, the discharge pressure pulsates, which causes the life of the pump to be shortened. Therefore, as a means for preventing volume fluctuation, a groove 18 for releasing volume fluctuation between the tooth tips of the drive gear 7 and the driven gear 8 is provided.

  Next, the configuration of the drive gear 7 and the driven gear 8 will be described. The drive gear 7 has a connecting portion 7g that connects the cylindrical portion 7f and the tip surface 7d. The connecting portion 7g is smaller in thickness in the height direction than the tooth tip surface 7d and the cylindrical portion 7f. More specifically, the order of the tooth tip surface 7d height> the cylindrical portion 7f height> the connecting portion 7g height. The connecting portion 7g is connected so as to approach the cylindrical portion 7f from the tooth tip surface 7d, and is inclined with respect to the drive shaft 5.

  As shown in FIG. 4, the drive shaft support portion 10 f of the upper casing 10 has a cylindrical shape protruding downward from the upper surface of the upper casing 10. The lower end of the drive shaft support portion 10f is located in the vicinity of the upper end of the cylindrical portion 7f having a height lower than the tooth tip surface 7d. According to this configuration, there is no portion that protrudes from the upper portion of the upper casing 10 while having a sufficient length to support the drive shaft 5. Thus, the overall height of the gear pump can be kept low. Further, the upper and lower shaft support lengths of the drive shaft 5 (drive shaft support portion 10f−drive shaft support portion 9f) can be shortened as much as possible, and the influence on the drive gear 7 due to the swinging around the support portion is exerted. Can be suppressed. Moreover, by suppressing the length of the drive shaft 5, there is little deflection of the shaft, further reducing the material cost.

  Moreover, the dimension of the cylindrical portion 7f in the height direction of the drive gear 7 is lower at the upper side than the lower side at the center of the cross section in the installed state. Thereby, it is possible to visually determine which is the upper surface or the lower surface at the time of assembly, and an assembly error can be prevented.

  Furthermore, in the circumferential direction of the connecting portion 7g of the drive gear 7, a plurality of communication holes 7e that connect the upper surface and the lower surface of the drive gear 7 are provided at predetermined intervals. The communication hole 7e is disposed concentrically around the cylindrical portion 7f.

  Here, the effect of the communication hole 7e will be described. The conventional gear pump has a configuration in which there is no gap inside the gear so that liquid such as water does not flow into the gear (between the tooth tip and the rotating shaft) and stay there. On the other hand, in the present embodiment, a communication hole 7e is provided, and water can be discharged using a relative pressure difference between the upper and lower sides of the communication hole 7e.

  That is, the liquid existing in one space above or below the drive gear 7 is a space on the side where the pressure is low due to the pressure difference between the top and bottom of the drive gear 7 (the other space below or above the drive gear 7 where no liquid exists, Move through the communication hole 7e.

  When the drive gear 7 (and the driven gear 8) is rotated, the liquid that is the transfer fluid accumulated between the cylindrical portion 7f and the tooth tip surface 7d of the drive gear 7 is discharged from the center of the drive gear 7 to the outside by centrifugal force. Works.

  Further, by providing an inclination so that the connecting portion 7g connecting the tooth tip surface 7d and the cylindrical portion 7f is lowered toward the drive shaft 5, the drive gear 7 (and the driven gear 8) rotates when the drive gear 7 rotates. A pressure difference generated in the upper and lower spaces is promoted, and a force that discharges the liquid held between the driving gear 7 and the upper casing 10 and the driving gear 7 and the middle casing 11 to the outside by surface tension acts.

  However, when there is no communication hole 7e between the cylindrical portion 7f and the tooth tip surface 7d and a simple recess is formed, the recess is depressurized when the drive gear 7 rotates, and the liquid accumulated in the recess is less likely to be discharged out of the recess.

  Therefore, by providing the communication hole 7e as in the present embodiment, the decompressed state of the concave portion can be released, and the liquid between the cylindrical portion 7f and the tooth tip surface 7d can be discharged to the outside of the drive gear 7, and the retention can be prevented. Can be suppressed. In this way, the liquid that has entered the upper surface or the lower surface of the drive gear 7 can be discharged to the opposite side (the lower surface for the upper surface, the upper surface for the lower surface). The discharged liquid is discharged to the outside due to the centrifugal force generated by the rotation of the drive gear 7 and the pressure difference generated by the rotation of the connecting portion 7g that connects the tooth tip surface and the cylindrical portion 7f, and from the inter-tooth region 7c or the groove 18 or the like. It is guided to the discharge port 10b side. That is, it is possible to prevent the transfer fluid, such as water, from staying for a long period of time and to have a pump configuration with excellent hygiene.

  Further, an injection point for injecting resin into the mold is provided in the connecting portion 7g of the drive gear 7 and the like. As a result, the burrs and the like are positioned sufficiently away from the upper casing 10 and the middle casing 11, so that the burrs and the like are prevented from coming into contact with the upper casing 10 and the middle casing 11 when the drive gear 7 rotates, and the suction capacity is reduced. Reduction and noise can be suppressed.

  Next, the driven gear 8 similarly includes a connecting portion 8g that connects the cylindrical portion 8f and the tooth tip surface 8d. The connecting portion 8g is smaller in thickness in the height direction than the tooth tip surface 8d and the cylindrical portion 8f. More specifically, the order of tooth tip surface 8d height≈cylindrical portion 8f height> connecting portion 8g height. The connecting portion 8g is connected so as to approach the cylindrical portion 8f from the tooth tip surface 8d, and is inclined with respect to the rotation axis.

  Furthermore, by providing the connecting portion 8g connecting the tooth tip surface 8d and the cylindrical portion 8f so as to be lowered toward the rotation support shaft 15, the driven gear 8 (and the drive gear 7) is rotated when the driven gear 8 (and the drive gear 7) rotates. The pressure difference generated in the upper and lower spaces is promoted, and the force that discharges the liquid held between the driven gear 8 and the upper casing 10 and the driven gear 8 and the middle casing 11 to the outside by surface tension acts.

  In the circumferential direction of the connecting portion 8g, a plurality of communication holes 8e that connect the upper surface and the lower surface of the driven gear 8 are provided at predetermined intervals. The communication hole 8e is arranged concentrically around the cylindrical portion 8f. By this communication hole 8e, the pressure reduction state of the concave portion between the cylindrical portion 8f and the tooth tip surface 8d of the driven gear 8 is released, and the liquid between the cylindrical portion 8f and the tooth tip surface 8d is discharged to the outside of the driven gear 8. And retention can be suppressed.

  The principle of liquid discharge from the recess is the same as that described in the drive gear 7. The discharged liquid is discharged to the outside by a centrifugal force generated by the rotation of the driven gear 8, and is guided to the discharge port 10b side from the inter-tooth region 8c or the groove 18 or the like. That is, it is possible to prevent the transfer fluid, such as water, from staying for a long period of time and to have a pump configuration with excellent hygiene.

  The rotation support shaft insertion hole upper end portion 8b of the driven gear 8 is positioned at a height substantially equal to the height of the tooth tip surface 8d. The upper end portion of the rotation support shaft 15 is positioned at a predetermined distance from the inner surface of the rotation support shaft insertion hole upper end portion 8b. Thereby, even when the driven gear 8 rotates and fluctuates up and down, the rotation support shaft insertion hole upper end portion 8b does not contact the upper end portion of the rotation support shaft 15, and the generation of noise can be suppressed.

  Further, an injection point for injecting the resin into the mold is provided in the connecting portion 8g of the driven gear 8 or the like. As a result, the burrs and the like are positioned sufficiently away from the upper casing 10 and the middle casing 11, so that the burrs and the like are prevented from coming into contact with the upper casing 10 and the middle casing 11 when the driven gear 8 rotates, and the suction capacity is reduced. Reduction and noise can be suppressed.

  The drive gear 7 and the driven gear 8 are made of resin, but are not solid molded products because of the communication holes 7e and 8e and the connecting portions 7g and 8g. Thereby, the cost can be reduced by suppressing the materials used. Moreover, the waiting time required for mold release can be shortened and productivity can be improved. Moreover, if it is resin with lubricity, it can rotate smoothly with little rotational resistance.

  The drive gear 7 and the driven gear 8 are made of resin, while the drive shaft 5 and the rotation support shaft 15 are made of metal (for example, steel). Since the drive shaft 5 and the rotation support shaft 15 are made of metal, the shaft can be formed thin. The thinner the shaft, the smaller the rotational load torque against the radial load (torque = radial load × radius × friction coefficient), and the shaft can rotate smoothly with little rotational resistance.

  Here, for example, if the drive gear 7 and the driven gear 8 are also made of metal, the mass becomes excessive, which is not suitable for reducing the size and weight of the gear pump. On the other hand, if the drive shaft 5 and the rotation support shaft 15 are made of resin, the shaft strength is insufficient and sufficient reliability cannot be obtained.

  In addition, either or both of the gap between the drive gear 7 and the drive shaft 5 and the gap between the driven gear 8 and the rotation support shaft 15 of the present embodiment can be inserted through the shaft and rotate together with each gear. The dimensions are In this way, if the shaft-gear clearance is reduced as much as possible, the clearance between the tooth tip surfaces 7d, 8d and the inner peripheral wall 10e of the upper casing 10 can be kept uniform, so that the tooth tip surfaces 7d, 8d and the upper casing 10 Noise can be reduced by preventing contact with the inner peripheral wall 10e.

  Next, a refrigerator equipped with a gear pump will be described. As shown in FIG. 5, the refrigerator main body 101 of this embodiment has the refrigerator compartment 102, the ice making room 103, the upper freezer compartment 104, the lower freezer compartment 105, and the vegetable compartment 106 from upper direction. As an example, the refrigerator compartment 102 and the vegetable compartment 106 are storage rooms in a refrigerator temperature zone of approximately 3 to 5 ° C. In addition, the ice making chamber 103, the upper freezer compartment 104, and the lower freezer compartment 105 are storage rooms in a freezing temperature zone of approximately −18 ° C.

  The outside of the refrigerator main body 101 and the inside of the refrigerator are separated by a heat insulating box 110 formed by filling a foam heat insulating material (foamed polyurethane) between the inner box 110a and the outer box 110b. Further, the heat insulating box 110 of the refrigerator main body 101 is mounted with a plurality of vacuum heat insulating materials 118.

  The refrigerator compartment 102a, the upper freezer compartment 104, and the ice making chamber 103 (see FIG. 1, the upper freezer compartment 104 is not shown in FIG. 2) are separated by a heat insulation partition wall 112a, and the heat insulation partition wall 112b. Thus, the lower freezer compartment 105 and the vegetable compartment 106 are separated.

  In the ice making chamber 103, an ice tray 125 that freezes the supplied water to make ice, an ice detecting lever 124 that is a lever for determining the amount of ice in the ice storage container below the ice tray 125, and ice making There is provided an automatic ice making machine 122 provided with a driving unit 123 which is a driving means for driving the plate 125 and the ice detecting lever 124.

  In the refrigerator compartment 102, a water supply tank 126 that is a water storage unit that can be removed and supplied, a gear pump 1 that pumps water from the inside of the water supply tank 126, and a water supply path 129 that supplies water from the gear pump 1 to the ice tray 125 are provided. ing.

  As described above, according to this embodiment, the following effects can be obtained.

  First, a drive gear 7 that is rotated by the drive source 2, a driven gear 8 that meshes with the drive gear 7, and a pump chamber in which the drive gear 7 and the driven gear 8 are arranged (the upper casing 10 and the middle casing 11 are partitioned). The drive gear 7 and the driven gear 8 are formed with communication holes 7e and 8e that communicate with the upper surface and the lower surface, respectively. The drive gear 7 includes a gear portion (tooth surface 7d). And a cylindrical portion 7f provided with a drive shaft insertion hole 7a for inserting the drive shaft 5, and a connecting portion 7g for connecting the gear portion and the cylindrical portion 7f. The driven gear 8 includes a gear portion (tooth tip surface 8d). ), And a cylindrical portion 8f having a rotation support shaft insertion hole 8a through which the rotation support shaft 15 is inserted, and a connection portion 8g for connecting the gear portion and the cylindrical portion 8f, and connecting the drive gear 7 and the driven gear 8 The portions 7g and 8g are connected to the drive shaft 5 side and the rotation It has a lower inclined support shaft 15 side, respectively, to discharge to the lower or upper liquid entering into the respective upper or lower surface of the drive gear 7 and the driven gear 8 communication holes 7e, from 8e. Thereby, it is possible to prevent the transfer fluid, such as water, from staying on the upper surface or the lower surface of the gear for a long period of time, and to have a pump configuration with excellent hygiene.

  The drive gear 7 has a drive shaft insertion hole 7a through which the drive shaft 5 is inserted, and the drive shaft support portion formed on the upper surface of the casing that supports the drive shaft 5 projects inward from the outer surface of the casing. It is. Thus, there is no portion protruding outward from the upper casing 10 while having a sufficient length to support the drive shaft, and the overall height of the gear pump 1 can be kept low.

  The drive gear 7 is formed with a drive shaft insertion hole 7a through which the drive shaft 5 is inserted, and the driven gear 8 is formed with a rotation support shaft insertion hole 8a through which the rotation support shaft 15 is inserted. The clearance between the drive shaft 5 and / or the clearance between the rotation support shaft insertion hole 8a and the rotation support shaft 15 allows the drive shaft 5 or the rotation support shaft 15 to be inserted, and the drive gear 7 or the driven gear 8 rotate integrally. It is a dimension to do. Thereby, since the clearance gap between the tooth tip surfaces 7d and 8d and the inner peripheral wall 10e of the upper casing 10 can be kept uniform, contact between the tooth tip surfaces 7d and 8d and the inner peripheral wall 10e of the upper casing 10 is prevented. Noise can be reduced.

  In addition, the refrigerator has a refrigeration temperature zone chamber and a freezing temperature zone chamber divided into a water storage unit disposed in the refrigeration temperature zone chamber, and an ice making unit disposed in the refrigeration temperature zone chamber to receive water supply from the water storage unit And a gear pump that inhales water from the water storage section and discharges it to the ice tray. Thereby, the vibration and noise of the gear pump are reduced, and the influence of resonance and resonance when incorporated in the refrigerator main body can be reduced.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. In addition, a part of the configuration of a certain embodiment can be replaced with another configuration. Further, it is possible to add or delete a part of the configuration of the embodiment.

  Further, the upper casing 10, the middle casing 11, and the lower casing 9 are names for convenience of explanation, and do not limit the upper and lower positions. In the present embodiment, an example in which these are arranged in order from the top (that is, an example in which the motor 2 is positioned below) has been described. For example, a configuration in which the lower casing 9, the middle casing 11, and the upper casing 10 are arranged from the top. (That is, a configuration in which the motor 2 is positioned above). Further, there may be an example in which there is a difference in height between the suction port 10a and the discharge port 10b through which the fluid enters and exits (for example, a posture of sucking the fluid from below and sending it upward) or vice versa. That is, it is possible to provide a gear pump excellent in hygiene and a refrigerator including the gear pump, which can discharge the liquid in the upper part or the lower part of the gear regardless of the posture.

1 Gear pump 2 Motor (drive source)
2a Output shaft 3a First reduction gear 3b Second reduction gear 3c Seal member 4 Motor housing portion 4a Engaging claw 5 Drive shaft 5a D cut surface 6 Sealing member 7 Drive gear 7a, 11e1 Drive shaft insertion holes 7c, 8c Tooth tip Inter-region 7d, 8d Tooth tip surface 7e, 8e Communication hole 7f, 8f Cylindrical part 7g, 8g Connection part 8 Driven gear 8a Rotation support shaft insertion hole 8b Rotation support shaft insertion hole upper end 9 Lower casing 9c, 10c, 11c Fastening hole (Screw hole)
9d1 Lower engagement portion 9e1 Output shaft communication hole 9e2 Rising portion 9f, 10f Drive shaft support portion 10 Upper casing 10a Suction port 10b Discharge port 10d1 Upper first engagement portion 10d2 Upper second engagement portion 10d3 Upper third engagement portion 10e Inner peripheral wall 10g Groove part 11 Middle casing 11d1 Middle first engagement part 11d2 Middle second engagement part 11e2 Rotation support shaft lower end support part 12 Fastening member (screw)
15 Rotation support shaft 16 Screw 17 Screw hole 18 Groove 19 Annular seal member

Claims (2)

A drive gear that rotates about a vertical rotation axis by a drive source; a driven gear that meshes with the drive gear and rotates about a vertical rotation axis; and a pump chamber in which the drive gear and the driven gear are arranged; In the gear pump with
The drive gear and the driven gear are each formed with a communication hole communicating the upper surface and the lower surface,
The drive gear includes a gear part, a cylindrical part having an insertion hole for inserting a drive shaft, and a connecting part for connecting the gear part and the cylindrical part,
The driven gear includes a gear portion, a cylindrical portion having an insertion hole through which the rotation support shaft is inserted, and a connecting portion that connects the gear portion and the cylindrical portion,
The connecting portions of the drive gear and the driven gear have slopes that become lower on the drive shaft side and the rotation support shaft side, respectively, and liquid that has entered the upper or lower surface of each of the drive gear and the driven gear. A gear pump that discharges downward or upward from the communication hole.   A refrigerator in which a refrigeration temperature zone chamber and a refrigeration temperature zone chamber are partitioned, and a water storage unit arranged in the refrigeration temperature zone chamber and a water storage unit arranged in the refrigeration temperature zone chamber and receiving water from the water storage unit An ice tray, and a refrigerator comprising the gear pump according to claim 1, wherein the gear pump according to claim 1 is sucked and discharged into the ice tray.