JPS6075783A - Gear pump or gear motor - Google Patents

Abstract

PURPOSE:To prevent a clearance from being unevenly generated between gears and side plates due to a warp of the side plate from its high pressure side to its low pressure side of fluid acting on the side plate, by guiding the fluid of high pressure to the total area of a back face and its peripheral edge part in the side plate of a gear pump or a gear motor. CONSTITUTION:A body 3 are formed in a thickness W1 equal to the thickness W2 of gears 1, 2, providing side plates 6, 7, having a larger contour than that of an opening part of the body 3, and mounting covers 4, 5. The periphery of supporting shafts 8, 9 and a low pressure side port 12 in an external face of the side plates 6, 7 is closely sealed by each packing 18, 19, 20. Then the gears and the side plates are uniformly pressed by guiding the high pressure of fluid in a high pressure side port 11 to act on the total area of a back face 6b and its peripheral edge part 6d in the side plates 6, 7 outside the packings 18, 19, 20.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Application [Jr Industry] The present invention relates to a circumscribed gear pump or motor that can be used in the field of hydraulic equipment and the like.

(B) Prior art As shown in FIG. 1, this type of gear pump or motor has M side plate f to V
It is known that fS is in contact. However, in the conventional one, the side plate f is fitted into the inner periphery of the body C,
The high-pressure fluid on the discharge side is guided to the back surface g side of the side plate f to statically balance the fluid pressure in the axial direction acting on the side plate f, and the elastic repulsive force of the banking h etc. is applied to the surface of the side plate f. i is pushed against the tooth surfaces d and e of the gears a and b to prevent the high pressure fluid on the discharge side from leaking to the suction side through the tooth surfaces 6.0. Therefore, high accuracy is required in the surface angle between the outer circumferential surface J nB of the side plate f and the surface i portion, the fitting gap between the outer circumferential surface j of the side plate f and the inner circumferential surface of the body C, etc. There's a problem. Moreover, as shown in FIG. 2, in the conventional type, a groove m is provided at a position separating a high pressure area H and a low pressure area on the back surface g of the side plate f, and the gasket h is fitted into this groove m. The high pressure fluid on the discharge side is introduced only into the high pressure region H formed on one side of the gasket h. Therefore, the side plate f receives an old force in the direction of arrow X due to the difference between the fluid pressure in the high pressure area H and the fluid pressure on the low pressure area side, and the outer peripheral surface j of the side plate f on the low pressure area side It will be strongly pressed against the circumferential surface k. the result,
The outer peripheral edge of the side plate f on the low pressure region side is deformed in the thickness direction as shown by the imaginary line in FIG.
A gap is created between the non-deformed part and the south sides d and e. Therefore, there is a problem in that it is difficult to improve the volumetric efficiency even though it is processed with high precision.

(C) 1] The present invention was made with a focus on such resentment.
We have developed a pump or motor that is easy to manufacture without requiring high processing precision, and that can effectively prevent leakage of high-pressure fluid from the discharge side to the suction side and achieve high volumetric efficiency. The purpose is to provide.

(d) Opening of the cylindrical body housing the structure [A circumscribed gear pump with four covers attached to one end and a side plate interposed between the inner surface of the cover and the south side of the gear Alternatively, in the motor, the width of the body is set to be approximately equal to the tooth width of the gear so that the tooth side of the gear is aligned with the opening end surface of the body and the road surface, and the outer peripheral edge of the surface of the side plate is set to be approximately equal to the tooth width of the gear. It is characterized in that it is attached to the end face and is configured so that high-pressure fluid on the discharge side can be guided to the entire outer peripheral edge of the back surface of the side plate.

(E) Example Below, an example of the present invention is shown in Fig. 4 and 5 IN.
＜＜ Then, you will be happy.

FIG. 4 is a front view of an example of a gear pump according to the present invention. This gear pump has a rear cover 4 and a front force/fence 5 at one end of a body 3 housing an oil feeding gear 1.2, and an inner surface 4a of each cover 4.5, , 5a and the tooth surfaces 1a, 2a of the gears 1, 2, respectively, are interposed with side plates 6.7. Gear 1.2 is a j upper gear that meshes with each other,
The spindle 8.9 of each of these gears 1.2 is
-4 and 5 are supported. The body 3 is cylindrical, and its width W1 is set to be equal to the face width W2 of the gears 1 and 2. In other words, the side surfaces 1a and 2a of the gears 1 and 2 are set flush with the open end surface 3a of the body 3. On the other hand, the side plate 6 is a disc-shaped member having a larger diameter than the opening width of the body 3, and its surface 6a
The outer peripheral edge 6C is attached to the opening end surface 3a of the body 3. The side plate 6 has a high pressure port 11 communicating with a discharge port (not shown), a low pressure port 1-12 communicating with a suction port (not shown), and a shaft hole 1 into which the support shaft 8.9 is fitted.
3°14 is the perforation. An annular groove 15, 16, 17 surrounding the low pressure port 12 and the shaft hole 13, 14 is provided on the back surface 6b of this side root 6.
16.17 is equipped with a saw-shaped nogu, 2 kinogs 18.19.20, and these nokunking 18.19, ? The outside of 0 is defined as a high pressure region H, and the inside of 0 is defined as a low pressure region L. In other words, the fluid is introduced into the entire outer peripheral edge 6d of the back surface 6b of the side plate 6 at a height F on the discharge side. Note that the side plate 7 has a substantially symmetrical shape to the side plate 6.

With such a configuration, the high-pressure fluid on the discharge side is guided to the entire outer peripheral edges 6d and 7d of the back surfaces 6b and 7b of the side plates 6.7, so that the high-pressure fluid and A biasing force in a direction perpendicular to the axis due to a pressure difference with the low pressure fluid does not act. Therefore, there is no inconvenience such as the outer peripheral edge of the side plate being pressed against the inner peripheral surface of the body and deformed. Therefore, the fluid on the high pressure side
It is possible to effectively prevent leakage to the low pressure side through the south side surfaces 1a and 2a of 11-, and achieve high volumetric efficiency. In addition, since it is not necessary to fit the side plate 6.7 into the inner part of the body 3, the perpendicularity between the surface of the side plate and the outer circumferential surface and the fitting gap between the outer circumference r+'+i and the inner circumferential surface of the body It is easy to manufacture without the inconvenience of requiring high precision. Moreover, with such a plow, the minute gap between the side plate 6.7 and the tooth side surfaces 1a, 2a can be precisely adjusted by changing the width of the body 3, and the volumetric efficiency can be improved. It can be set to a desired value.

Note that the shape of the high-pressure region into which the high-pressure fluid is introduced on the Ill outlet side is of course not limited to that described in 19. For example,
It may be as shown in Figure WS6. That is,
What is shown in FIG. 6 is the low pressure port 12 and the shaft hole 13.1.
4 are surrounded by a common backing 22 fitted into a heart-shaped bank 21, and the outer periphery of this banking 22 is defined as a high-pressure region H.

Further, in the above embodiment, a case was explained in which a groove for attaching the backing 2 to the side plate was provided, but for example, as shown in FIG. Grooves 16' and 17' are provided on the inner surface 4a'5a' of '5',
Various modifications are possible, such as fitting bankings 19' and 20' into these grooves 16' and 17' to separate the high-pressure region and the low-pressure region.

It can also be implemented as a gear motor that outputs.

(f) Effects Since the present invention has the configuration described below, it is easy to manufacture without requiring high processing accuracy, and furthermore,
Effectively prevents leakage of high pressure fluid from the discharge side to the suction side
It is possible to provide a vehicle pop or motor that can achieve high volumetric efficiency in L.

[Brief explanation of drawings]

Fig. 1 is a front sectional view showing a conventional example, Fig. 2 is a sectional view taken along line II-II in Fig. 1, and Fig. 3 is a - - in Fig. 2.
4 is a front sectional view showing one embodiment of the present invention; FIG. 5 is a sectional view taken along v-vV;A in FIG. 4; and FIG. 6 is a sectional view showing another embodiment of the present invention. FIG. 7 is a sectional view corresponding to FIG. 5 showing an example, and FIG. 7 is a front sectional view showing still another embodiment of the present invention. 1.2・Yu◆1ru i 4j 311 battle・Hoti 4.4゛, 5,5゛・Fist・Cover 6.6゛, 7.7゛...Side plate 6a, 7a11φO surface 6b, 7b fist・11 Back side 6c, 7C... Outer periphery of front side 5d, 7d... Outer periphery of back side Agent Patent attorney Akazawa-Kawasen Figure 1 Figure 2 Figure 3 ■-Σ Figure 5

Claims (1)

[Claims] Attach a cover to the open end of the cylindrical body that houses the gear.
In a circumscribed gear pump or motor, which has a side plate interposed between the inner surface of the cover and the tooth side of the gear, the width of the body is set approximately equal to the tooth width of the gear. The tooth side of the gear is aligned with the opening end surface of the body and the road surface, and the outer peripheral edge of the front surface of the side plate is attached to the opening end of the body, and the entire outer peripheral edge of the back surface of the side plate is filled with heavy pressure fluid on the discharge side. A gear pump or motor characterized in that it is configured to be able to guide.