JP5258814B2 - Pump device and brake control device - Google Patents

Description

  The present invention relates to a pump device that performs a pump action by rotation of a pair of gears and a brake control device including the pump device.

  As this type of technology, the technology described in Patent Document 1 below is disclosed. In this publication, the low pressure side of the tooth tip seal portion is formed with a gap when no discharge pressure is generated, and the tooth tip seal portion is deformed by a pressure difference in a high pressure state where the discharge pressure is generated. The thing which obtains the seal | sticker structure which closely_contact | adheres a clearance gap and implement | achieves high volumetric efficiency is disclosed.

JP 2006-207415 A

However, since the volumetric efficiency at the time of low pressure is lowered in the above-described conventional technology, there is a problem that the pump cannot be reduced in size.
The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a pump device in which volumetric efficiency does not decrease even at a low pressure, and a brake control device including the pump device. It is in.

  In order to achieve the above object, in the present invention, a space that opens to the low pressure region is formed in the tooth tip seal block.

  According to the present invention, volumetric efficiency at low pressure can be improved.

2 is a hydraulic circuit in a hydraulic control unit including the gear pump according to the first embodiment. It is a perspective view of the gear pump of Example 1. It is sectional drawing of the gear pump of Example 1. FIG. It is a disassembled perspective view of the gear pump of Example 1. FIG. 3 is an enlarged view of a first side plate of Example 1. FIG. 3 is an enlarged view of a deformation promotion hole of Example 1. FIG. It is a figure which shows the mode of a deformation | transformation at the time of the gear pump drive of the tooth-tip seal block of Example 1. FIG. It is a figure which shows the shape of the deformation | transformation promotion hole of another Example.

[Example 1]
[Brake control device overall configuration]
A brake control device and a pump device according to a first embodiment of the present invention will be described. FIG. 1 shows a hydraulic circuit in a hydraulic control unit 1 having circumscribed gear pumps 19P and 19S (hereinafter, gear pump 19). The gear pump 19 is a pump applied to an automobile brake system, and is mounted on a known antilock brake control, vehicle behavior control, automatic brake control, or brake-by-wire system.
The left front wheel wheel cylinder W / C (FL) and the right rear wheel wheel cylinder W / C (RR) are connected to the P system of the hydraulic pressure control unit 1, and the right front wheel wheel cylinder W is connected to the S system. / C (FR) and wheel cylinder W / C (RL) on the left rear wheel are connected.
A gear pump 19P and a gear pump 19S are provided for each of the P system and the S system, and the gear pump 19 is driven by the motors MP and MS. The master cylinder M / C and the suction side of the gear pump 19 are connected by pipelines 11P and 11S (hereinafter, pipeline 11). On each pipeline 11, gate-in valves 2P and 2S, which are normally closed electromagnetic valves, are provided. In addition, check valves 6P and 6S (hereinafter referred to as check valve 6) are provided on the pipeline 11 between the gate-in valves 2P and 2S (hereinafter referred to as gate-in valve 2) and the gear pump 19, The check valve 6 allows the flow of brake fluid in the direction from the gate-in valve 2 toward the gear pump 19 and prohibits the flow in the opposite direction.
The discharge side of each gear pump 19 and each wheel cylinder W / C are connected by pipes 12P and 12S (hereinafter, pipe 12). On each pipeline 12, solenoid-in valves 4FL, 4RR, 4FR, 4RL (hereinafter referred to as solenoid-in valves 4), which are normally open solenoid valves corresponding to the respective wheel cylinders W / C, are provided. Further, check valves 7P and 7S (hereinafter referred to as check valves 7) are provided on the pipes 12 and between the solenoid-in valves 4 and the gear pumps 19. Allows the brake fluid to flow in the direction toward the solenoid-in valve 4 and prohibits the flow in the opposite direction.

Furthermore, each pipeline 12 is provided with pipelines 17FL, 17RR, 17FR, 17RL (hereinafter, pipeline 17) that bypass each solenoid-in valve 4, and these pipelines 17 include check valves 10FL, 10RR, 10FR, 10RL (hereinafter, check valve 10) is provided. Each check valve 10 allows the flow of brake fluid in the direction from the wheel cylinder W / C toward the gear pump 19 and prohibits the flow in the opposite direction.
Master cylinder M / C and conduit 12 are connected by conduits 13P and 13S (hereinafter referred to as conduit 13), and conduit 12 and conduit 13 merge between gear pump 19 and solenoid-in valve 4. On each pipeline 13, gate-out valves 3P and 3S (hereinafter referred to as gate-out valves 3), which are normally open solenoid valves, are provided.
Each pipeline 13 is provided with pipelines 18P and 18S (hereinafter referred to as pipeline 18) that bypass each gate-out valve 3. The pipeline 18 includes check valves 9P and 9S (hereinafter referred to as check valve 9). ) Is provided. Each check valve 9 allows the flow of brake fluid in the direction from the master cylinder M / C side toward the wheel cylinder W / C, and prohibits the flow in the opposite direction.
Reservoirs 16P and 16S (hereinafter referred to as reservoir 16) are provided on the suction side of the gear pump 19, and the reservoir 16 and the gear pump 19 are connected by pipe lines 15P and 15S (hereinafter referred to as pipe line 15). Check valves 8P and 8S (hereinafter referred to as check valve 8) are provided between the reservoir 16 and the gear pump 19, and each check valve 8 allows a flow of brake fluid in a direction from the reservoir 16 to the gear pump 19. , Prohibit flow in the opposite direction. The wheel cylinder W / C and the pipeline 15 are connected by pipelines 14P and 14S (hereinafter, pipeline 14), and the pipeline 15 and the pipeline 14 merge between the check valve 8 and the reservoir 16. Each pipeline 14 is provided with solenoid-out valves 5FL, 5RR, 5FR, and 5RL (hereinafter, solenoid-out valves 5), which are normally closed solenoid valves.
Each solenoid valve (gate-in valve 2, gate-out valve 3, solenoid-in valve 4, solenoid-out valve 5) is controlled by a brake control unit. The brake control unit calculates the normal brake control according to the driver's operation based on the input signal of each sensor and the driver's brake pedal operation state, anti-skid brake control (ABS), vehicle behavior stabilization control (VDC), inter-vehicle distance The vehicle information such as distance control and obstacle avoidance control is used to calculate tire slip and vehicle behavior, calculate the braking force (all wheels) required for the vehicle, and control necessary for each wheel. Calculate the power target value.

[Configuration of gear pump]
FIG. 2 is a perspective view of the gear pump 19. FIG. 2 is drawn so that the housing 20 can be seen through so that the configuration inside the housing 20 can be seen. FIG. 3 is a cross-sectional view taken along the line AA in FIG. FIG. 4 is an exploded perspective view of the gear pump 19. FIG. 5 is an enlarged view of the first side plate 24. 5A is a perspective view of the first side plate 24, FIG. 5B is a front view of the first side plate 24, and FIG. 5C is a side view of the first side plate 24.
The gear pump 19 includes a housing 20 having a pump chamber 21 therein, a drive gear 22, a driven gear 23 disposed in the pump chamber 21, and a first side plate provided adjacent to the side surfaces of the drive gear 22 and the driven gear 23. 24, a second side plate 25 and a pump body 29 in which the second side plate 25 is integrally formed.

(Housing configuration)
The housing 20 includes a cylindrical portion 26 having a pump chamber 21 having an inside formed in a cup shape with a bottom, and a substantially rectangular plate-shaped flange portion 27 formed at the bottom of the cylindrical portion 26. Bolt insertion holes 28 for inserting bolts for fixing the gear pump 19 to the hydraulic pressure control unit 1 are formed at the four corners of the flange portion 27. A drive shaft hole 33 that supports a drive shaft 30 to be described later and a driven shaft hole 34 that supports the driven shaft 31 are formed at the bottom of the pump chamber 21.

(Gear configuration)
The drive gear 22 is provided on the drive shaft 30, and the driven gear 23 is provided on the driven shaft 31. The drive shaft 30 is connected to the motor M, and the drive gear 22 rotates together with the drive shaft 30. The driven gear 23 meshes with the drive gear 22, and the driven gear 23 rotates as the drive gear 22 rotates.

(Structure of pump body)
The pump body 29 has a second side plate 25 formed in a convex shape on the side surface in the axial direction of the substantially cylindrical cylindrical portion 32. The second side plate 25 is formed so as to seal the side surfaces of the drive gear 22 and the driven gear 23. The vicinity of the engaging portion of the drive gear 22 and the driven gear 23 is sealed to the tooth tips of the drive gear 22 and the driven gear by the second side plate 25. Further, in the portion other than the vicinity of the engagement portion of the drive gear 22 and the driven gear 23 of the second side plate 25, a portion adjacent to the tooth portion of the second side plate 25, the drive gear 22 and the driven gear 23 is cut out. Portions 35 and 36 are formed. In addition, a suction hole 37 cut out to the side surface of the pump body 29 is formed at a position where the driving gear 22 and the driven gear 23 of the second side plate 25 start to mesh by rotation. Further, the upper surface of the second side plate 25 is formed in substantially the same shape as the arcs of the tooth tip seal surfaces 46 and 47 of the first side plate 24 to be described later, and the tip 55 on one end side of the tooth tip seal surfaces 46 and 47 is formed. A support portion 51 is formed to support the.
The pump body 29 is formed with a drive shaft hole 38 for supporting the drive shaft 30 and a driven shaft hole 39 for supporting the driven shaft 31. The drive shaft hole 38 is formed to penetrate from the side surface of the second side plate 25 to the opposite side surface of the pump body 29 in the axial direction. The driven shaft hole 39 is formed from the surface of the second side plate 25 to the middle of the pump body 29 in the axial direction. The drive shaft 30 passes through the drive shaft hole 38 to the opposite side surface of the second side plate 25 of the pump body 29, and is connected to the motor M on the opposite side surface side of the second side plate 25.

(Configuration of the first side plate)
The first side plate 24 is made of resin, and includes two disk portions 42 and 43 having through holes 40 and 41 and a tooth tip seal block 44 that seals the tooth tips of the drive gear 22 and the driven gear 23. It is integrally formed.
One side surfaces of the disk portions 42 and 43 seal the side surfaces of the drive gear 22 and the driven gear 23. A suction hole 45 penetrating both side surfaces is formed at a position where the drive gear 22 and the driven gear 23 of the first side plate 24 start to mesh with each other. The suction hole 45 communicates with the suction hole 37 of the second side plate 25.
The tooth tip seal block 44 is formed so as to protrude from the disk portions 42 and 43 toward one side surface. A pair of arcuate tooth tip seal surfaces 46 and 47 are formed on the surface of the tooth tip seal block 44 on the disk portions 42 and 43 side. The diameters of the tooth tip seal surfaces 46 and 47 are substantially equal to the diameters of the tooth tips of the drive gear 22 and the driven gear 23. Further, the upper surface portion 48 of the tooth tip seal block 44 is formed in a square shape, and a holding portion 49 in which the protruding end portion is cut out in a U-shape is formed. The holding portion 49 is provided with a reinforcing member 50 formed in a U-shape. By forming the upper surface portion 48 of the tooth tip seal block 44 in a square shape, the deformation of the entire tooth tip seal block 44 toward the drive gear 22 and the driven gear 23 can be promoted.
In addition, a deformation promoting hole 54 that opens to the other side surface of the first side plate 24 is formed on the top of the tooth tip seal surfaces 46 and 47. As shown in FIG. 3, the deformation promoting hole 54 is formed up to the position of the tooth tip seal surfaces 46 and 47 with respect to the axial thickness of the tooth tip seal block 44, in other words, the support portion of the second side plate 25. The tip portion 55 supported by 51 is not formed. The deformation promoting hole 54 is a hole for promoting the deformation of the tooth tip seal surfaces 46 and 47 in the direction away from the tooth tips of the drive gear 22 and the driven gear 23 particularly when the discharge pressure is high.

FIG. 6 is an enlarged view of the deformation promoting hole 54. A dotted line A in FIG. 6 is a line indicating an upper limit position where the deformation promoting hole 54 is installed in order to ensure the strength of the tooth tip seal block 44. Also, a dotted line B in FIG. 6 is a line indicating a lateral limit position where the deformation promoting hole 54 is installed in order to ensure the strength of the tooth tip seal block 44. In addition, 1 of dotted lines A and B is based on the following idea. Since the positions of the dotted lines A and B are located in the vicinity of the oil seal groove 52, a differential pressure force is received each time the pressure is increased. In addition, it receives a force corresponding to the amount of crushing due to the assembly of the oil seal 53. The strength against these forces is required, and the thickness E between the oil seal groove 52 and the dotted lines A and B is appropriately set.
Maximum pressure x pressure receiving area <shear area (thickness E part) x yield stress
<Creep Permissible Stress> Oil Seal Reaction Force / Shear Area Further, the alternate long and short dash line C in FIG. 6 is a line indicating the upper limit position where the tip seal surfaces 46 and 47 can be deformed. The seal block 44 is deformed in proportion to the pressure with the support portion 51 as a fulcrum, but the position of the alternate long and short dash line C is set in a range where the deformation due to the pressure from the outside of the seal block 44 and the deformation due to the pressure from the inside cancel Just do it. That is, the deformation promoting hole 54 may be created in the hatched area D shown in FIG.
An oil seal groove 52 is formed on the other side surface of the first side plate 24 along the outer periphery of the side surface of the first side plate 24. On the inner peripheral side of the oil seal groove 52, through holes 40 and 41, a suction hole 45, and a deformation promotion hole 54 are formed. An oil seal 53 is inserted into the oil seal groove 52. The oil seal 53 is in close contact with the other side surface of the first side plate 24 and the bottom surface of the housing 20, the inner peripheral side of the oil seal 53 is a low brake fluid pressure region, and the outer peripheral side of the oil seal 53 is a high brake fluid pressure region. It is divided into. That is, the suction hole 45 and the deformation promoting hole 54 are opened in the low pressure region on the inner peripheral side of the oil seal 53.

[Action]
The conventional tooth tip seal portion is formed so as to have a gap between the tooth tip seal surface and the gear tip when the discharge pressure of the gear pump is low. Further, when the discharge pressure is high, the tip seal portion is deformed so that the tip seal surface comes close to the gear tip. High volumetric efficiency was achieved. However, there is a problem that the volumetric efficiency is lowered when the discharge pressure is low.
In order to increase the volumetric efficiency when the discharge pressure is low, it is also possible to form a gap between the tooth tip seal surface and the gear tip when the discharge pressure is low. It is done. However, when the discharge pressure is high, the tooth tip seal surface comes into contact with the gear tip and the gear tip seal surface is scraped off by the gear. For this reason, there is still a gap between the tooth tip seal surface and the gear tip.
In the first embodiment, therefore, a deformation promoting hole 54 that opens in the low pressure region is formed in the tooth tip seal block 44.

FIG. 7 is a view showing a state of deformation of the tooth tip seal block 44 not provided with the deformation promotion hole 54 when the gear pump 19 is driven (FIG. 7A), and the tooth tip seal block 44 provided with the deformation promotion hole 54. It is a figure (Drawing 7 (b)) showing a mode of modification at the time of gear pump 19 drive.
When the discharge pressure becomes high, a high pressure acts on the upper surface portion 48 of the tooth tip seal block 44, and a lower pressure acts on the tooth tip seal surfaces 46, 47 as the suction hole 45 is closer. Therefore, in the tooth tip seal block 44 not provided with the deformation promotion hole 54, the whole tooth tip seal block 44 is deformed to the drive gear 22 and the driven gear 23 side. Therefore, the design is made so that the tooth tip seal surfaces 46 and 47 and the tooth tips of the drive gear 22 and the driven gear 23 are in contact with each other at high pressure. Alternatively, the tooth tip seal surfaces 46 and 47 are scraped by the tooth tips of the drive gear 22 and the driven gear 23 at a high pressure so that the tooth tip seal surfaces 46 and 47 are in contact with the tooth tips of the drive gear 22 and the driven gear 23. Will be formed. For this reason, when the discharge pressure is low, the gap between the tooth tip seal surfaces 46, 47 and the drive gear 22 and the driven gear 23 becomes large, so that the volumetric efficiency at low pressure is low.
On the other hand, when the discharge pressure becomes high as in the first embodiment, in the tooth tip seal block 44 provided with the deformation promoting hole 54, the whole tooth tip seal block 44 is deformed to the drive gear 22 and the driven gear 23 side. . At this time, the tooth tip seal surfaces 46 and 47 are deformed in a direction in which the tooth tip seal surfaces 46 and 47 are separated from the drive gear 22 and the driven gear 23 by the force of the deformation promoting hole 54 acting on the tooth tip seal surfaces 46 and 47. For this reason, the clearance between the tooth tip seal surfaces 46, 47 and the drive gear 22 and the driven gear 23 can be made substantially equal both when the discharge pressure is low and when the discharge pressure is high. As a result, even when the discharge pressure is low, the gap between the tip seal surfaces 46, 47 and the drive gear 22 and the driven gear 23 can be reduced, and the volumetric efficiency at low pressure can be increased.
In the first embodiment, the deformation promoting hole 54 is not formed in the tip portion 55 supported by the support portion 51 of the second side plate 25. Thereby, it can suppress that the 2nd side plate 25 whole deform | transforms.

[effect]
(1) A pump chamber 21 provided in the housing 20, a drive gear 22 disposed in the pump chamber 21, driven to rotate by a motor M (electric motor) and performing a pump action, and a driven gear meshing with the drive gear 22 23 and a pair of first side plate 24 and second side plate 25 that are provided adjacent to both side surfaces of each gear 22, 23 and suppress leakage of hydraulic fluid from the side surfaces of each gear 22, 23, The first side plate 24 is disposed between the wall of the pump chamber 21 and each of the gears 22 and 23, and the base end portion is integrally formed to seal the tooth tips of the gears 22 and 23. The tooth tip seal block 44 having the seal surfaces 46 and 47 formed thereon, the first side plate 24 formed between the wall of the pump chamber 21 and the first side plate 24, and disposed in the annular accommodating portion, the pump chamber 21. Oil seal 53 (seal member) that divides the interior into a low pressure region and a high pressure region The second side plate 25 includes a support portion 51 that supports the tip portion 55 of the tooth tip seal block 44. The tooth tip seal block 44 opens in a partitioned low pressure region, and the rotational directions of the gears 22, 23 The deformation promoting holes 54 (spaces) are formed along the lines.
Therefore, even when the discharge pressure is low, the gap between the tooth tip seal surfaces 46, 47 and the drive gear 22 and the driven gear 23 can be reduced, and the volumetric efficiency at low pressure can be increased.

(2) A brake control device for supplying the discharged brake fluid to the wheel cylinder W / C via the hydraulic pressure control unit 1 (hydraulic pressure control means), and a pump chamber 21 provided in the housing 20 And a drive gear 22 that is disposed in the pump chamber 21 and rotated by a motor M (electric motor) to perform a pump action, a driven gear 23 that meshes with the drive gear 22, and adjacent to both side surfaces of the gears 22 and 23. The pair of first side plate 24, second side plate 25, and first side plate 24, which suppress the leakage of hydraulic fluid from the side surfaces of the gears 22, 23, are provided on the wall of the pump chamber 21, A tooth tip seal block 44 which is disposed between the gears 22 and 23 and has a base end portion integrally formed to form tooth tip seal surfaces 46 and 47 which seal the tooth tips of the gears 22 and 23; Continuous to the first side plate 24 between the wall of the pump chamber 21 and the first side plate 24 And an oil seal 53 (seal member) that is disposed in the annular housing groove formed to partition the inside of the pump chamber 21 into a low pressure region and a high pressure region, and the second side plate 25 is the tip of the tooth tip seal block 44. The support portion 51 that supports the portion 55 is provided, and a deformation promoting hole 54 (space) that allows deformation of the second side plate is formed at a position corresponding to the radially outer region inside the tooth tip seal block 44.
Therefore, even when the discharge pressure is low, the gap between the tooth tip seal surfaces 46, 47 and the drive gear 22 and the driven gear 23 can be reduced, and the volumetric efficiency at low pressure can be increased.

(3) The deformation promoting hole 54 (space) is not formed in the tip portion 55 supported by the support portion 51.
Thereby, it can suppress that the 2nd side plate 25 whole deform | transforms.

[Other Examples]
As described above, the present invention has been described based on the first embodiment. However, the specific configuration of each invention is not limited to each embodiment, and even if there is a design change or the like without departing from the gist of the invention. Are included in the present invention.
FIG. 8 is a view showing variations in the shape of the deformation promoting hole 54. For example, in the first embodiment, as shown in FIG. 8A, one deformation promoting hole 54 is provided substantially parallel to the upper surface portion 48 of the tooth tip seal block 44.
As shown in FIG. 8B, along the curved surfaces of the tooth tip seal surfaces 46 and 47, the suction hole 45 side (low pressure side) is brought close to the tooth tip seal surfaces 46 and 47, and is opposite to the suction hole 45. The deformation promoting hole 54 may be formed so that the (high-pressure side) is away from the tooth tip seal surfaces 46 and 47. As a result, the wall thickness between the high pressure side tip seal surfaces 46, 47 and the deformation promoting hole 54 is smaller than the thickness between the low pressure side tip seal surfaces 46, 47 and the deformation promoting hole 54. Since the thickness is increased, the deformation amount of the low-pressure side tip seal surfaces 46 and 47 and the deformation amount of the high-pressure side tip seal surfaces 46 and 47 can be made constant.
Furthermore, as shown in FIG. 8C, a plurality of deformation promoting holes 54 having a circular cross-sectional shape may be provided. Accordingly, when the deformation promoting hole 54 is formed after the outline of the first side plate 24 is formed, the deformation promoting hole 54 can be easily formed.

1 Hydraulic pressure control unit (hydraulic pressure control means)
19 Gear pump
20 Housing
21 Pump room
22 Drive gear
23 Driven gear
24 1st side plate
25 Second side plate
44 Tooth tip seal block
46 Tooth tip seal surface
51 Support
53 Oil seal (seal member)
54 Deformation promotion hole (space)
55 Tip
M motor (electric motor)

Claims (3)

A pump chamber provided in the housing;
A drive gear disposed in the pump chamber and driven to rotate by an electric motor to perform a pump action, and a driven gear meshing with the drive gear;
A pair of side plates that are provided adjacent to both side surfaces of each gear and suppress leakage of hydraulic fluid from the side surfaces of each gear;
With
One of the side plates is
Arranged between the wall of the pump chamber and the gears;
A tooth tip seal block in which a base end portion is integrally formed and a tooth tip sealing surface for sealing the tooth tip of each gear is formed;
A seal member which is formed in the side plate between the wall of the pump chamber and the side plate, and is arranged in an annular housing portion and divides the pump chamber into a low pressure region and a high pressure region,
The other side plate includes a support portion that supports a tip portion of the tooth tip seal block,
The tooth tip seal block opens to the partitioned low pressure region, and a space is formed along the rotation direction of each gear. A brake control device for supplying discharged brake fluid to a wheel cylinder via a hydraulic pressure control means,
A pump chamber provided in the housing;
A drive gear disposed in the pump chamber and driven to rotate by an electric motor to perform a pump action, and a driven gear meshing with the drive gear;
A pair of side plates provided adjacent to both side surfaces of each gear and suppressing leakage of hydraulic fluid from the side surfaces of each gear;
One of the side plates is disposed between the wall of the pump chamber and each gear,
A tooth tip seal block having a base end portion formed integrally and forming a tooth tip seal surface that seals the tooth tips of each gear, and continuous to the side plate between the wall of the pump chamber and the side plate. A seal member that is arranged in an annular housing groove formed by dividing the pump chamber into a low pressure region and a high pressure region;
With
The other side plate is provided with a support portion that supports a tip portion of the tooth tip seal block, and forms a space that allows deformation of the side plate at a position corresponding to a radially outer region inside the tooth tip seal block. A brake control device characterized by that. In the pump device according to claim 1 or the brake device according to claim 2,
The pump device and the brake control device, wherein the space is not formed at the tip portion supported by the support portion.

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