JPH08219029A - Gear pump - Google Patents

Abstract

PURPOSE: To allow a side plate to be uniformly pressed to a driving side gear and a driven side gear by a sealing member in the case of forming an external gear pump in such a way that the side plate is provided on the side faces of the driving side gear and driven side gear and that the high pressure fluid of a discharge part is partially guided to the back face side of the side plate to press the side plate to the side faces of the driving side gear and driven side gear. CONSTITUTION: A sealing member 11 is formed being provided with a first seal part 11a for surrounding a discharge part 6 and a suction part 8, a second seal part 11b surrounding the suction part 8 and partitioning the discharge part 6 and the suction part 8, a connecting part 11c for connecting the first and second seal parts 11a, 11b to each other on the suction part 8 side. and a groove part 11d formed on the recessed part bottom side of a cover part in the connecting part 11c so as to connect one side and the other side of the discharge part 6 to each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a circumscribing type gear pump provided with a driving side gear which is rotationally driven and a driven side gear which is engaged with the driving side gear and rotationally driven together.

[0002]

2. Description of the Related Art In a gear pump as described above, a case for supporting a driving side gear and a driven side gear is provided with a discharge portion facing the occlusal start portion of the driving side gear and the driven side gear and a suction portion facing the occlusal end portion. Is provided so that the fluid sucked into the suction portion is sent out to the discharge portion along the inner peripheral surface of the case.

[0003] In this case, a side plate for partitioning the gear teeth of the driving side gear and the driven side gear between the gear teeth by being abutted on both side surfaces of the driving side gear and the driven side gear is provided, and high pressure of the discharge portion is provided. There is a structure in which a part of the fluid is guided to the back surface side of the side plate and the side plate is pressed against the side surfaces of both the driving side gear and the driven side gear. This reduces fluid leakage between the gear teeth of the drive-side gear and the driven-side gear, and prevents a reduction in volumetric efficiency of the gear pump.

[0004]

As described above, the side plate is provided so as to be fitted over both side surfaces of the driving side gear and the driven side gear, and a part of the high pressure fluid of the discharge portion is provided on the back side of the side plate. If it is configured to guide, a sealing member that separates the high-pressure discharge section side and the low-pressure suction section side on the back side of the side plate is required. In the gear pump as described above, when the high pressure discharge part side and the low pressure suction part side are partitioned by the seal member, the side plates are stably pressed over the side surfaces of both the drive side gear and the driven side gear. Therefore, it is an object of the present invention to configure the sealing member so as to have high durability.

[0005]

The feature of the present invention resides in that the gear pump as described above is constructed as follows. The drive side gear and the driven side gear have a lid portion that opens one side surface, and the gear teeth of the drive side gear and the driven side gear are abutted against both sides of the drive side gear and the driven side gear on the lid side. Equipped with side plates that partition between
A first closed loop is provided which forms a recess on the end surface of the lid, which communicates the discharge section with the back side of the side plate, and includes a seal member which fits into the recess on the end surface of the lid, and which surrounds the outside of the discharge section and the suction section. A seal part, a closed loop second seal part that surrounds the suction part inside the first seal part and partitions the discharge part and the suction part;
The seal includes a connecting portion that connects the first and second seal portions on the suction portion side, and a groove portion that is formed on the bottom side of the recess of the lid portion in the connecting portion and that connects one side and the other side of the discharge portion. The member is formed.

[0006]

With the construction of the present invention, for example, when the driving gear 3 is rotationally driven in the clockwise direction on the plane of FIG. 6 and the driven gear 4 is rotationally driven in the counterclockwise direction on the plane of FIG. The fluid that has entered the suction portion 8 is
Further, the gear teeth of the driven gear 4 are carried along the inner peripheral surface of the case 1 to form a high-pressure fluid, which is sent to the discharge portion 6.

Along with this, part of the high-pressure fluid in the discharge part 6 enters the recesses 2b and 2c of the lid part 2 (between the first and second seal parts 11a and 11b of the seal member 11) and the side plate 10 Enter the back side. In this way, the side plate 10 is pressed against the side surfaces of both the drive-side gear 3 and the driven-side gear 4 by a part of the high-pressure fluid in the discharge portion 6. In this case, in the recesses 2 b and 2 c of the lid part 2, the region on the discharge part 6 side and the region on the suction part 8 side are the first and second seal parts 1 of the seal member 11.
Since it is partitioned by 1a and 11b, a part of the high-pressure fluid in the discharge part 6 flows from the recessed parts 2b and 2c of the lid part 2 into the suction part 8a.
There is no such thing that the force that goes in and presses the side plate 10 against the side surfaces of the drive side gear 3 and the driven side gear 4 is weakened.

As described above, when a part of the high-pressure fluid of the discharge part 6 enters the region on the discharge part 6 side (between the first and second seal parts 11a and 11b of the seal member 11),
One side and the other side of the area on the side of the discharge portion 6 are provided with the groove portion 11d of the seal member 11 (the first and second seal portions 11a and 11b of the seal member 11, the connecting portion 11c, and the recess portion 2 of the lid portion 2).
It will be connected via the space surrounded by b and 2c). As a result, the high-pressure fluid that has entered the area on the discharge portion 6 side circulates through the groove 11d of the seal member 11, so that pressure (side plate 10 is set on the drive side gear 3 by the side plate 10) at each portion of the area on the discharge portion 6 side. Also, the variation in the distribution of the force pressing the side surface of the driven gear 4) is suppressed, and it becomes uniform. As a result, the side plate 10 is pressed uniformly on both side surfaces of both the drive-side gear 3 and the driven-side gear 4 without any bias.

[0009]

As described above, in the gear pump provided with the side plates that are applied to both sides of the driving side gear and the driven side gear, a part of the high-pressure fluid in the discharge portion is guided to the rear side of the side plate. In this case, by circulating a high-pressure fluid in the seal member, the side plates can be pressed uniformly on both sides of the drive gear and the driven gear without unevenness. The leakage of fluid from between the gear teeth of the gear was reduced, and the performance of the gear pump could be improved.

Since the distribution of the pressure (the force for pressing the side plate against the side surfaces of the driving side gear and the driven side gear) becomes uniform in each portion (each portion in the region on the discharge portion side) in the seal member, the seal member The above-mentioned pressure is strongly applied to the part, and the part is not damaged quickly, so that the durability of the seal member can be improved.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 4 and 5, the outer shape of the gear pump is formed by the case 1 and the lid portion 2. A drive-side gear 3 and a driven-side gear 4 which are rotationally driven by a power source such as an engine (not shown) are provided, and one shaft portion 3a, 4a of the drive-side gear 3 and the driven-side gear 4 serves as a bush 5. Is rotatably supported by the case 1 via a drive side gear 3
Also, the driven gear 4 is engaged.

As shown in FIGS. 3, 5 and 6, the drive side gear 3
A discharge part 6 facing the occlusal start part of the driven gear 4 and a discharge port 7 orthogonal to the discharge part 6 are formed in the case 1, and the suction facing the occlusal end part of the drive gear 3 and the driven gear 4 is inhaled. The part 8 is formed on the case 1. As shown in FIGS. 4 and 6, a pair of laterally elongated groove portions 1a for collecting fluid leaking near the shaft portions 3a, 4a is formed in the case 1, and the pair of groove portions 1a and the suction portion 8 are connected to each other. Recess 1
b is formed on the case 1.

As shown in FIGS. 3, 5 and 6, in the lid portion 2 which opens one side surface of the driving side gear 3 and the driven side gear 4, the concave portion 2a and the suction portion 8 of the case 1 facing the discharging portion 6 are provided. Opposing suction ports 9 are formed, and as shown in FIGS. 4 and 5, the other shaft portions 3b and 4b of the drive gear 3 and the driven gear 4 rotate to the lid portion 2 via the bush 5. It is freely supported.

As shown in FIGS. 5 and 6, on the end surface of the lid portion 2 on the case 1 side, a closed loop-shaped first groove portion 2b that surrounds the outside of the recess 2a (discharge portion 6) and the suction port 9 (suction portion 8). (Corresponding to a concave portion), a second loop-shaped second groove portion 2c (corresponding to a concave portion) which surrounds the suction port 9 (suction portion 8) and the shaft portions 3b and 4b inside the first groove portion 2b and communicates with the concave portion 2a (discharging portion 6). ) Is formed, and the first and second groove portions 2b and 2c are connected on the suction port 9 (suction portion 8) side. Second
A third groove portion 2d is formed inside the groove portion 2c so as to communicate the recesses of the shaft portions 3b and 4b and the suction port 9 (suction portion 8).

The first convex portion 2e, the first and second groove portions 2b, 2 located between the first groove portion 2b and the concave portion 2a (ejection portion 6).
a pair of second convex portions 2f positioned between the two c, a third convex portion 2g positioned between the second groove portion 2c and the concave portion 2a (ejection portion 6),
The 4th convex part 2h located between the 2nd groove part 2c and the suction port 9 (suction part 8), and the 5th convex part 2i located between the 2nd and 3rd groove parts 2c and 2d are formed.

As shown in FIGS. 5 and 6, the gear teeth of the drive side gear 3 and the driven side gear 4 are abutted against both side surfaces of the drive side gear 3 and the driven side gear 4 on the lid portion 2 side. A side plate 10 for partitioning the spaces is provided. The pair of holes 10a of the shafts 3b, 4b of the drive side gear 3 and the driven side gear 4, the pair of first notches 10b formed in the hole 10a, the discharge portion 6 of the case 1 (the discharge of the lid portion 2). The first concave portion 10c that does not close the port 7), the second concave portion 10d that does not close the suction portion 8 of the case 1 (the suction port 9 of the lid portion 2), and the suction portion 8 of the case 1 (the lid portion 2) Of the suction port 9), the pair of second cutouts 10e, the drive side gear 3 and the driven side gear 4, the first opening 10f located at the occlusal start portion, the drive side gear 3 and the driven side. A second opening 10g located at the occlusal end portion of the side gear 4 is formed in the side plate 10.

As shown in FIGS. 5 and 6, the seal member 1 is inserted into the first and second groove portions 2b and 2c of the end surface of the lid portion 2.
1 is provided. The first groove portion 2b is inserted into the recess 2a
A first seal portion 11a surrounding the (discharge portion 6) and the suction port 9 (suction portion 8), and a second groove portion 2c inside the first seal portion 11a to enter the suction port 9 (suction portion 8) and the shaft portion. Surrounding 3b and 4b, recessed portion 2a (discharge portion 6)
Closed loop second seal part 11b for partitioning the suction port 9 (suction part 8) and the shaft parts 3b, 4b from each other, and the suction port 9
On the (suction part 8) side, the first and second seal parts 11a,
The connecting portion 11c for connecting 11b, and the groove portion 1 formed on the bottom side of the first and second groove portions 2b, 2c in the connecting portion 11c for connecting one side and the other side of the concave portion 2a (ejection portion 6).
The seal member 11 is formed by including 1d.

With the structure described above, in the gear pump, the driving gear 3 is rotationally driven in the clockwise direction on the paper in FIG. 6, and the driven gear 4 is rotationally driven in the counterclockwise direction on the paper accordingly. As a result, as shown in FIGS. 3 and 6, the fluid that has entered the suction portion 8 of the case 1 from the suction port 9 of the lid portion 2 has an inner circumference of the case 1 due to the gear teeth of the drive gear 3 and the driven gear 4. It is carried along the surface and is delivered to the ejection portion 6 of the case 1 from both left and right sides of the paper surface of FIG.

Along with this, as shown in FIGS. 1, 2 and 6, a part of the high-pressure fluid in the discharge part 6 is formed between the second seal part 11b of the seal member 11 and the first convex part 2e of the lid part 2. The first and second seal portions 11a, 1 of the seal member 11
From between 1b, it reaches both of the second convex portions 2f of the lid portion 2.
As described above, when part of the high-pressure fluid reaches the second convex portions 2f of both of the lid portions 2 from the discharge portion 6, the pressure drops in the middle thereof. In this case, due to the gear teeth of the driving-side gear 3 and the driven-side gear 4, a part of the high-pressure fluid sent from the suction portion 8 along the inner peripheral surface of the case 1 is provided with the second cutout portions on both sides of the side plate 10. 10e enters the lid portion 2 side, and joins with the high-pressure fluid reaching both the second convex portions 2f of the lid portion 2 from the discharge portion 6 as described above.

As a result, the pressure is restored, and the high-pressure fluid whose pressure has been restored is in the groove portion 11d of the seal member 11 (the first and second seal portions 11 of the seal member 11).
a, 11b, the connecting portion 11c, and an elongated space surrounded by the first and second groove portions 2b, 2c of the lid portion 2) and communicate with each other. As described above, the high-pressure fluid reaching the second convex portions 2f of both lid portions 2 from between the second seal portion 11b of the seal member 11 and the first convex portion 2e of the lid portion 2 in FIG. The outer peripheral portion on the back side of the side plate 10 (the second concave portion 10d of the suction portion 8)
The side plate 10 is pressed against the side surfaces of the drive-side gear 3 and the driven-side gear 4 by hitting the outer peripheral portion in the vicinity).

In FIG. 6, the drive side gear 3 is rotationally driven in the clockwise direction on the paper surface, and the driven side gear 4 is rotationally driven in the counterclockwise direction on the paper surface,
When the fluid is delivered to the discharge portion 6 by the gear teeth of the driving side gear 3 and the driven side gear 4, a part of the high-pressure fluid remains between the gear teeth of the driving side gear 3 and the driven side gear 4, and the driving side It is sent to the suction portion 8 side while being compressed as the gear 3 and the driven gear 4 rotate. In this case, the high-pressure fluid that remains between the gear teeth of the drive-side gear 3 and the driven-side gear 4 and is about to be compressed near the discharge portion 6 is the first opening 10f of the side plate 10 shown in FIGS. From the second seal portion 1 of the seal member 11.
It enters between 1b and the 1st convex part 2e of the lid part 2. This supplements the high-pressure fluid that presses the side plate 10 against the side surfaces of the drive gear 3 and the driven gear 4.

As described above, the high-pressure fluid remaining between the gear teeth of the driving gear 3 and the driven gear 4 escapes from the first opening 10f of the side plate 10, and then the driving gear 3 and the driven gear. When the gear teeth of the side gear 4 reach the suction portion 8 side, the gear teeth of the drive side gear 3 and the driven side gear 4 open, and a negative pressure is generated in this open part. In this case, when the gear teeth of the drive side gear 3 and the driven side gear 4 start to open on the suction part 8 side as shown in FIGS. 1 and 2, the fluid of the suction part 8 opens from the second opening 10g of the side plate 10. The negative pressure is suppressed by entering the beginning part.

As shown in FIGS. 4 and 6, the drive side gear 3
Also, the fluid leaked to the case 1 side shafts 3a, 4a of the driven gear 4 is a pair of the groove 1a and the recess 1b of the case 1.
It is sent to the suction part 8 via. As shown in FIGS. 1 and 2, the fluid leaking near the shaft portions 3b, 4b of the drive-side gear 3 and the driven-side gear 4 on the lid portion 2 side is a pair of first cutout portions 10b of the side plate 10 and the drawing. The third groove portion 2 of the lid portion 2 shown in FIG.
It is sent to the suction part 8 via d.

[Other Embodiments] In the above-described embodiment, the side plate 10 is provided only on the lid portion 2 side, but as shown in FIG. 7, the side plate is provided on both the lid portion 2 side and the case 1 side. It may be configured to include 10. In this case, the side plate 10 on the side of the lid portion 2 has a shape as shown in FIG. 6 similarly to the above-described embodiment, and is provided with the end face structure of the lid portion 2 and the sealing member 11 as shown in FIGS. 5 and 6. The side plate 10 on the case 1 side is not provided with the structure of the end surface of the lid portion 2 and the seal member 11 as shown in FIGS. 5 and 6. As a result, in the side plate 10 on the case 1 side, the second cutout portion 1 in the side plate 10 of FIG.
0e, the first and second openings 10f, 10g are no longer needed,
The first cutout portion 10b is located so as to face the groove portion 1a of the case 1 shown in FIG. As shown in FIG. 8, the suction port 9 of the lid 2 may be eliminated and the case 1 may be provided with the suction port 9. The discharge port 7 of the case 1 shown in FIGS. 3 and 5 may be omitted, and the discharge port 7 may be provided in the lid portion 2 as shown in FIGS. 9 and 10.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a front view of an end surface of a case with a side plate and a seal member attached to the case side.

FIG. 2 is a perspective view near the end surface of the case with a side plate and a seal member attached to the case side.

FIG. 3 is a vertical sectional side view of the gear pump.

FIG. 4 is a cross-sectional plan view of the gear pump.

FIG. 5 is an exploded perspective view of the entire gear pump

FIG. 6 is an exploded front view of the entire gear pump.

FIG. 7 is a cross-sectional plan view of a gear pump according to another embodiment.

FIG. 8 is a vertical sectional side view of a gear pump according to another embodiment.

FIG. 9 is a vertical sectional side view of a gear pump according to another embodiment.

FIG. 10 is a vertical sectional side view of a gear pump according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 case 2 lid part 2b, 2c recessed part of end face of lid part 3 drive side gear 4 driven side gear 6 discharge part 8 suction part 10 side plate 11 seal member 11a first seal part 11b seal member second seal part 11c Connection part of seal member 11d Groove part of seal member

Claims (1)

[Claims] 1. A case (1) supporting a rotatably driven drive side gear (3) and a driven side gear (4) engaged with the drive side gear (3) and rotatably driven together, The discharge part (6) facing the occlusal start part of the drive side gear (3) and the driven side gear (4) and the suction part (8) facing the occlusal end part of the drive side gear (3) and the driven side gear (4). ) Are provided in the case (1), and the fluid sucked into the suction part (8) is supplied to the discharge part (6) along the inner peripheral surface of the case (1).
A gear pump configured to send to the drive gear, the drive gear (3) and the driven gear (4) including a lid portion (2) that opens one side surface of the drive gear (3) and the driven gear (4). A side plate (10) which is applied to both sides of the side gear (3) and the driven side gear (4) and partitions the gear teeth of the driving side gear (3) and the driven side gear (4) from each other. The recesses (2b) and (2c) that communicate the discharge part (6) and the back side of the side plate (10) are formed on the end surface of the lid part (2), and the recess part (2) of the lid part (2) is formed. A closed loop-shaped first seal part (11a) surrounding the outside of the discharge part (8) and the suction part (6), comprising a seal member (11) which enters the recesses (2b), (2c) of the end face; Inside the first seal part (11a), the suction part (8) is surrounded and the discharge part ( ) And the suction portion (8)
A closed loop-shaped second seal part (11b) for partitioning and a connecting part (11c) connecting the first and second seal parts (11a), (11b) on the suction part (8) side.
And a groove portion (11d) formed on the bottom side of the recesses (2b) and (2c) of the lid portion (2) in the connection portion (11c) and connecting one side and the other side of the discharge portion (6). A gear pump having the seal member (11) formed by: