JPS6248076B2 - - Google Patents

Description

[Detailed description of the invention] Technical field The present invention relates to a gear pump.

Prior Art Various types of gear pumps have been developed in the past. A typical example is to provide at least a pair of gears that mesh with each other in the pump chamber, provide a fluid inlet on one side of the meshing point and a fluid outlet on the other side, and connect each gear to the pump chamber. The pump chamber is separated into a fluid inlet side and a fluid outlet side with the meshing point as a boundary by appropriately approaching or contacting the inner surface, and by rotating these gears, fluid is sent from the fluid inlet side to the outlet side. ing. For example, JP-A No. 46-9782 and JP-A-48
- There is a disclosure in No. 11606. However, with conventional Kia pumps like this, the tips of the teeth come into contact with the inner surface of the pump chamber, so the contact surface wears out with use, resulting in greater fluid leakage during pump action, which reduces work efficiency. I had the problem of doing so.

In order to solve this problem, the applicant of the present application has provided a movable shoe inside the pump chamber so that the shoe comes into contact with the inner surface of the pump chamber instead of the inner surface of the pump chamber. A patent application has been filed for an invention in which the gear is pressed by the differential pressure between the fluid outlet side (low pressure side) and the fluid outlet side (high pressure side) (Japanese Patent Publication No. 61-51159). According to this, even if the above-mentioned wear occurs, the shoe is displaced by that amount and is pressed against the gear, so that it is possible to prevent fluid leakage from increasing and efficiency to decrease as in the above-mentioned conventional gear pump. be able to.

Although the invention according to the above patent application has excellent effects as described above, it has a problem that its assembly is a little troublesome.

OBJECTS OF THE INVENTION In view of the above points, an object of the present invention is to provide a gear pump that has the features of the invention related to the above patent application and is easy to assemble.

Structure of the Invention That is, the pump according to the present invention includes a manifold including a surface where an inlet duct and a discharge duct open, and an inlet and an outlet that communicate each of these ducts to the outside, and a manifold that is parallel to the above-mentioned surface of the manifold. a first side;
a unit plate having a second surface; at least one inlet provided in the plate and communicating with the inlet duct and an outlet communicating with the discharge duct; a first gear; , a first gear mounting means for supporting the first gear so that it can rotate freely in contact with the second surface; a second gear meshing with the first gear; and a second gear supported by the plate. a second gear attachment means; the manifold is separate from the first and second tooth attachment means, and the inlet and outlet of the plate are on opposite sides of the meshing point of the gear. and further comprising at least a portion of the first and second gears including the meshing point and at least two teeth of each gear on either side of the meshing point and the inlet. a pump chamber forming means for sealing against the plate so as to enclose the outer space of the surface; and a driving means for rotating one of the gears, the pump chamber forming means being arranged on both sides of the meshing point. an imperforate shoe attached to the plate covering a portion of the gear opposite the plate, the shoe having a first recess for rotation of the gear and a first recess in the first recess; and a second recess communicating with the inlet of the plate.

Effects and Effects of the Invention The pump according to the present invention has the above configuration, and when assembling the pump, the gear and shoe are not attached directly to the manifold, but are attached to a unit plate separate from the manifold. The pump can be assembled easily by attaching the plate to the manifold. Furthermore, it is possible to check the assembled state of the gears and between them and the shoe, and to check the performance of only those parts before assembling them into the manifold, making it possible to assemble the pump efficiently. Furthermore, during operation of the pump, the shoe is always pressed against the gear due to the differential pressure between the fluid inlet and outlet sides, and can maintain a tight seal with the gear.

Embodiments Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

As best shown in FIGS. 1 and 2, a manifold 11 is provided that roughly corresponds to the pump body of a general-purpose pump. Manifold 11
A unit plate 16 is provided along the inner surface of the manifold, which plate is separated from the surface of the manifold by a casket 17. These parts are
It is attached to a bracket 14 which is fixed to the casing of the motor 21 in various ways. Motor 21 has a shaft 22 connected to a cup-shaped magnet flange 23 by a hub 24. An annular drive magnet 26 is fixed to the flange 23. Flange 23 drives a driven magnet 27 that is mounted within magnet holder 28 and held by retainer 29 . Magnet holder 28 rotates about stationary mounting pin 81. A non-magnetic cap 12 is provided to separate the drive magnet 26 from the driven magnet 27. A recess 82 is formed in the bottom of cap 12 to receive the outer end of pin 81. The cap 12 has a shoulder 83 and an outwardly extending ridge 84 adjacent its open end.

Assembly of these parts takes place by means of a fastening ring 18. The ring is annular and the manifold 11
abutting a shoulder such as a flange 86 on the inner end of the holder. By means of screws 79 (FIG. 2), the fastening ring 18 is attached to the annular flange 1 attached to the bracket 14 of the motor 21 by means of screws 77.
It is fixed at 9. An aperture plate 76 abuts the outer peripheral edge of the bracket 14. A resilient washer 78 is interposed between plate 76 and shoulder 83 of cap 12. Therefore, when screw 79 is tightened, cap 12 is biased to the left as viewed in FIG. A pump cavity 13 is formed on the right side of the gasket 17.
The protrusion 84 of the cap abuts the flange 19. For such purpose, the fastening ring 18 abuts the flange 86 of the manifold 11 when the screw 79 is tightened.

Referring to FIGS. 4 and 8, mounted in the center of a hole in the unit plate 16 is a hollow shaft 31 held in place by a screw 91; A spring 93 is inserted that contacts the pin 81 and presses the pin into the recess 82 . Around the hollow shaft 31,
A drive gear 33 is rotatably attached.
A preferred driving means for the drive gear is the drive gear 3.
3 and inserted into corresponding holes in the magnet holder 28 are a plurality of drive pins 35 , which are parallel to the shaft 31 and the pin 81 . Therefore, the motor shaft 22
rotates, the drive magnet 26 rotates the drive magnet, which causes the drive gear 33 to rotate through the pin 35.
rotates around the hollow shaft 31.

In the preferred embodiment three gears are provided on the pump. The use of a third gear is optional, and for ease of explanation, reference will first be made to only one driven gear. Referring to FIG.
6 on the plate 16. Driven gear 34 is rotatable about shaft 32 and meshes with gear 33 .

Referring to FIGS. 6 and 7, plate 16
An inlet 36 is formed in and communicates with an inlet duct 88 within the manifold 11 . The inlet duct 88 of the manifold 11 is in communication with the inlet 38 which is connected by suitable means to the pipes of the pump. Also formed within the manifold 11 is a pump discharge duct 37 which communicates with an outlet 39 . The outlet 89 in the plate 16 is on the opposite side of the inlet 36 via the meshing points of the gears 33,34. Therefore, as gears 33, 34 rotate, fluid is forced from inlet 36 out of outlet 89.

In order to create a pump chamber within the pump cavity 13, a shoe 41 (FIGS. 3 and 4) is provided within the cavity 13. The shoe 41 has an inlet 36, a gear 33,
34 engagement points and about two teeth on either side of the engagement points, forming a seal with the top surface of one or more teeth.

The shoe 41 is attached to the plate 16 by screws 94.
It is supported by a pin 42 which is held in parallel to the shafts 31 and 32.
The edge of the shoe 41 has a notch 43 for the pin 35.
(Figure 3). A recess 44 is formed on the lower surface of the shoe 41 to create a gap for the gears 33 and 34 (see FIGS. 9 and 10).
figure). A deeper recess 46 is provided directly opposite the inlet 36 so that fluid entering through the inlet 36 enters the recess 46 and then passes through the recess 44 at the point of engagement of the gears. The hole 43 is
The pin 42 that supports 1 is received. An elongated narrow recess 47 is located between recesses 46 and 48. Recess 49 provides clearance for the end of shaft 32.

When the pump rotates, the pressure within the pump cavity 13 becomes the discharge pressure and the pressure within the duct 36 becomes the inlet pressure. This differential pressure causes the shoe 41 to
6 and the tops of gears 33 and 34. The recess 47 connected to the recess 46 ensures that such inlet pressure occurs over the face of the shoe in contact with the plate 16. However, when the pump is started, spring 51 is used to hold shoe 41 in place until the differential pressure takes over. A loop portion 52 is made in the spring 51 at its center. A screw 53 passes through the loop portion 52 and is screwed into the plate 16 to hold the spring 51.
One leg 54 of the spring 51 is around the outer surface of the shoe, the other twisted leg knitting the edge of the shoe 41 towards the meshing point of the gears 33,34.

As previously mentioned, there are three gears in this embodiment of the invention. A third gear 34a is rotatably mounted on shaft 32a held within desk 16 by screw 96a.
A second inlet 36a is formed in the plate 16 180° opposite the inlet 36. Show 41
The gears 33 and 34a are all similar to the gears 33 and 34a.
and the inlet 36a, and is held in place by a spring 51a, which is held in place by a screw 53a before pump pressure is generated. Gear 34a, shoe 41a and spring 51a are similar to gear 34, shoe 41 and spring 51, respectively.

Referring to FIG. 6, the shape of gasket 17 seals discharge duct 37 against desk 16, while otherwise allowing free communication with the various holes. The hole 98 has screws 91, 94,
96, 96a are formed in the face of manifold 11 to receive the heads. Irregularly shaped grooves 97 are provided in the plane of manifold 11 to communicate between holes 36, 36a in plate 16. Screws 99 hold plate 16 and socket 17 in place relative to manifold 11. When the pressure in the pump cavity 13 exceeds a predetermined value, the bypass 101 (FIG. 5) is opened. For this purpose, a recess 102 is provided in the manifold 11. A poppet valve 103 is provided in the recess 102 and is connected to the discharge opening 11 in the plate 16.
It has a rim 104 that seals around 4.
The poppet valve 103 has a washer 1 in contact with it.
07 into the sealed position by a spring 106 that engages the spring 106. The other end of the spring engages a spring retainer 108 positioned by a screw 102 threaded into the manifold 11. A gland 111 seals the hole for the screw 109 and is tightened by a tightening sleeve 113 that is screwed into the hole in the manifold 11. In order to adjust the position of the screw 109, an opening 112 is provided in the tightening sleeve 113.

When the pressure in pump cavity 13 exceeds the pressure regulated by screw 109, poppet valve 103 moves from its sealing position and fluid passes from cavity 13 through bypass passage 114 to plate 16 and manifold 11.
and returns to the entrances 36, 36a through the space 116 (FIG. 5) between them.

A modification of the gear pump system of the modular pump of the present invention is shown in FIGS. 12 and 13, in which an internal ring gear 121 is formed on a cup 120 which is an extension of the magnetic holder 28b. ing. Internal gear 121 engages gears 34b, 34c at the outer periphery of the pump, unencumbered by parts such as shoes. Internal gear wheel 12
By using 1, a high gear ratio of approximately 3 to 1 is obtained for the shaft 22b of the drive motor 21b, increasing the discharge amount.

Referring to FIG. 14, gasket 17d has a portion 123 that seals bypass discharge opening 114d of desk 16d, thereby preventing communication between it and the various inlets. A bypass passage 125 connects the recess 102 with the groove 97d at a point on the side of the washer 107d away from the desk 16d, so that when flow flows from the cavity 13d (as shown in FIG. 1) through the opening 114d. , Watshiya 10
7d and the bypass path 125
It passes through the groove 97d and reaches the pump inlet. This variation increases the force on spring 106d and leads to improved properties of the bypass path.

In other parts, the variant of FIGS. 12-14 is similar to that of FIGS. 1-11.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of the pump according to the present invention;
The figure is a left end view of Figure 1; Figure 3 is 3-3 in Figure 1.
Diagram: Figure 4 is a line 4-4 in Figure 3; Figure 5 is a sectional view showing a part of the bypass structure; Figure 6 is a line 6-6 in Figure 4; Figure 7 is a line 4-4 in Figure 3; Figure 1 is a line 7-7 of Figure 1; Figure 8 is a line 8-8 of Figure 3; Figure 9 is an elevational view of the shoe; Figure 10 is a side view of Figure 9; 11-11 line in the figure; FIG. 12 is a vertical sectional view showing another pump according to the present invention; FIG. 13 is a line 13-13 in FIG. 12; FIG. 14 is a gasket similar to FIG. 6. FIG. 15 is a partial elevational view showing another example of the bypass mechanism; FIG. 15 is a sectional view showing a part of another bypass mechanism. 16... Unit plate; 31... First gear attachment means (shaft); 32... Second gear attachment means (shaft); 33... First gear; 34... Second gear
Gear; 36...Inlet; 37...Discharge duct; 38
... Inlet; 39 ... Outlet; 41 ... Pump chamber forming means (shu); 89 ... Inlet duct; 89 ...
Ejection port.

Claims (1)

[Claims] 1. A manifold comprising a partition surface through which an inlet duct and a discharge duct open, and an inlet and an outlet communicating each of these ducts to the outside, and a first manifold parallel to the partition surface of the manifold. a unit plate having a surface and a second surface; at least one inlet provided in this plate and communicating with the inlet duct and an outlet communicating with the discharge duct; a first gear; and the plate. a first gear mounting means that is supported by the plate and supports the first gear so that it can rotate freely in contact with the second surface; a second gear that meshes with the first gear; and a second gear that is supported by the plate. a second gear attachment means; the manifold is separate from the first and second tooth attachment means, and the inlet and outlet of the plate are connected to each other at the meshing points of the gears. said inlet and at least a portion of said first and second gears disposed in opposite positions and further including said meshing point and at least two teeth of each gear on either side of said meshing point; A pump chamber forming means for sealing against the plate so as to enclose the outer space of the second surface; and a driving means for rotating one of the gears, the pump chamber forming means forming a seal at the meshing point of the second surface. A solid shoe is attached to the plate and covers the opposite part of the gear and the plate on each side, the shoe having a first recess for rotation of the gear and a first recess for the rotation of the gear. A fluid pump defining a recess and a second recess communicating with the inlet of the plate. 2. A fluid pump according to claim 1, including a spring on a plate that biases the shoe into contact with a surface of the gear opposite to the plate. 3. A fluid pump according to claim 1, comprising a cup and sealing means for sealing the edge of the cup against the plate, thereby forming a pump cavity. 4. A fluid pump according to claim 1, comprising an internal gear meshing with one of the gears and means for rotating the internal gear. 5. In the pump according to claim 1, the manifold has a bypass passage formed inside the partition surface, the plate has a bypass opening, and the pump further includes a bypass passage formed inside the partition surface, and a bypass opening formed in the plate. pump cavity defining means defining a pump cavity around the surface and surrounding the inlet and outlet of the plate, the pump chamber defining means and the first and second gears; valve means in said bypass passageway movable between a first sealing position and a second position remote from the plate; resilient means biased in a first position, a bypass passage communicating the bypass aperture with an inlet of the plate such that flow through the bypass aperture returns to the inlet hole. 6. A fluid pump according to claim 5, comprising adjustment means for adjusting the elastic means, said means being operable from the outside.