JP3174133B2 - Pump device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called radial piston type pump device used as a power source for a vehicle brake system, for example.

[0002]

2. Description of the Related Art A pump device of this kind is disclosed in
There is one disclosed in Japanese Patent Publication No. 142870. In this method, a shoe is interposed between the piston and the stator. When the piston is retracted into the cylinder hole due to external vibration when the pump device is not operating, the shoe falls off. In the event of misalignment or misalignment, problems such as breakage of the shoe itself or locking of the motor driving the rotor occur, and the predetermined pump function is lost. In order to achieve this, the cylinder hole in which the piston is housed has a stepped shape in which the center side of the rotor has a small diameter, and one end of a spring housed in this cylinder hole is supported by the step portion. The spring urges the shoe together with the piston toward the stator.

[0003]

In this type of pump device, the inner wall of the cylinder hole must be finished (for example, honing) with high precision because the piston slides, but the stepped portion is formed in the middle. If there is a portion, there is a problem that the inner wall near the step cannot be finish-processed among the inner walls from the rotor outer peripheral opening of the cylinder hole, which serves as the piston sliding area, to the step.

In order to solve the problem of the finishing, it is conceivable to mount a member such as a C-ring in the cylinder hole in order to support a spring end without stepping the cylinder hole. In this case, it is inevitable that the process of forming a groove for locking the C-ring in the cylinder hole and the work of incorporating the C-ring into the cylinder hole from the outer peripheral opening of the rotor become complicated. In addition, it is conceivable to lengthen the cylinder hole so that the vicinity of the step of the cylinder hole does not become the sliding area of the piston. However, in such a case, the rotor diameter becomes large, and the pump device becomes large. Will increase in size.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and it is possible to prevent the shoe from dropping and displacing without storing a spring for urging the shoe to a stator in a cylinder hole. It is an object of the present invention to provide a pump device that can prevent such a problem.

[0006]

In order to achieve the above object, a pump device according to the present invention comprises a rotor having a plurality of radially extending cylinder holes, and a rotor provided on an outer peripheral side of the rotor. a stator provided by decentering, of the cylinder bore
A piston, each slidably fitted to reciprocate by the relative rotation between the rotor and the stator, and a shoe interposed between the piston and the stator, said pin
A pump that engages a ston and biases the shoe together with the piston toward the stator, wherein the spring is disposed in a space defined between the outer periphery of the rotor and the stator. Is established ,
A base engaging the shoe and projecting from both ends of the base
And a pair of side portions abutting on the outer peripheral surface of the rotor.
And it is characterized by being provided independently for each of the pistons .

The spring has a plate-like shape with the pair of side portions.
With the said base portion is characterized by having a holding portion for holding the shoe relative to the piston.

[0008]

According to the above-described pump device of the present invention, it is not necessary to form a step for supporting the spring end in the cylinder hole or to incorporate a member for supporting the spring end. It can be formed.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. Note that the terms up, down, left, and right in the following description mean directions in each drawing.

FIG. 1 is a sectional view of a radial piston type pump device, wherein 1 is a pump device comprising a pump 2 and a motor-3, 4 is a pump body of the pump 2 and two block members. 5 and 6 are formed by fitting and connecting,
It has a recess 7 that opens upward, and this recess 7 is formed by a series of mounting holes 7A, large-diameter holes 7B, medium-diameter holes 7C, and small-diameter holes 7D that gradually decrease in diameter from above. . The pump body 4 extends downward from the bottom of the recess 7 of the pump body 4 along the axis thereof.
A shaft hole 8 opening on the lower surface is formed.

Reference numeral 10 denotes a shaft-shaped pintle, which is inserted into the shaft hole 8 from below the pump body 4, and a flange portion extending radially outward is engaged with a step portion of the shaft hole 8.
One end protrudes into the recess 7. Inside the pintle 10, an inflow channel 11 and an outflow channel 12 extending in the axial direction in parallel with each other are formed. The inflow passage 11 is opened in the recess 7, and is opened to the upper part of the peripheral surface of the pump body 4, and is connected to the working fluid reservoir through a suction port 13 communicating with the recess 7 through a pipe (not shown). The outflow passage 12 is provided with a check valve 14 inserted into the shaft hole 8 below the pintle 10.
Communicating with the entrance. The outlet of the check valve 14 is connected to an accumulator through a discharge port 15 opened on the peripheral surface of the pump body 4 through a pipe (not shown). A cylindrical member 16 is screwed into the lowermost portion of the shaft hole 8, and the cylindrical member 16 is screwed into the shaft hole 8 so that the pindle 1 is screwed.
0 is non-rotatably supported from below through a check valve 14.

Reference numeral 20 denotes a rotor having a central hole 21 penetrating in the axial direction thereof and a cylinder hole 22 intersecting with the central hole 21 and penetrating in the radial direction.
A cylindrical portion 23 provided concentrically with 1 protrudes axially upward from one end of the rotor 20. The cylindrical portion 23 is provided with a groove 24 penetrating in the radial direction. And the rotor
Reference numeral 20 denotes a center hole 21 fitted around the outer periphery of the pintle 10 so as to be rotatably supported by the pintle 10. The bottom is engaged via a spacer. Pistons 25 are housed in radially opposed portions of the cylinder hole 22, respectively. This piston 25 is
6 and an arcuate head 27 integrally formed at the tip of the shaft 26
The shaft portion 26 is slidably fitted in the cylinder hole 22 from the radial direction of the rotor 20, and is inserted into the cylinder hole 22 between the piston 25 and the pintle 10. A pressure chamber A is defined. Also, piston 2
A shoe 35 is attached to the head 27 of the fifth through a support member 30 from outside the diameter of the rotor 20. Each of the inflow path 11 and the outflow path 12 of the pintle 10 can communicate with the pressure chamber A according to the rotation of the rotor 20 through the holes 11a or 12a extending radially opposed to each other.

Reference numeral 36 denotes a ball bearing, which comprises an inner race 37, a ball 38, and an outer race 39. The ball bearing 36 is rotatably fitted and mounted in the middle diameter step portion 7C of the recess 7 of the pump body 4. The ring is fitted and fixed in the large-diameter hole portion 7B of the recess 7 from above the bearing 36 to prevent the bearing 36 from coming off. At this time, the ball bearing 3
6, along the axis is a predetermined amount eccentric radially relative to the axis of the rotor 20, the shoe 3 of the piston 25 the inner circumferential surface of the inner race 37 from the radially outward direction of the rotor 20
5 are arranged. The shoe 35 of the piston 25 comes into sliding contact with the inner peripheral surface of the inner race 37 in accordance with the rotation of the rotor 20, and the ball bearing 36 moves the piston 25 by eccentric rotation with the rotor 20. It has a function as a stator that reciprocates in the radial direction of the rotor 20.

Reference numeral 40 denotes a transmitting member for transmitting a rotational force from the motor 3 to the rotor 20, which has a diameter slightly smaller than the inner diameter of the cylindrical portion 23 of the rotor 20. An elongated hole 41 extending in the radial direction is formed in the center. The transmission member 40 has two protrusions 42 projecting radially outward from the outer periphery of the transmission member 40 fitted in the groove 24 provided in the cylindrical portion 23 so as to be slidable in the axial direction. An inflow port (not shown) that connects the recess 7 and the inflow path 11 is formed in a radial gap between the transmission member 40 and the cylindrical portion 23 of the rotor 20.

Reference numeral 45 denotes a mounting member interposed between the motor 3 and the pump body 4, and has a through hole 46 whose diameter is gradually reduced from above and a reduced diameter step portion 45A which protrudes downward. The reduced diameter step 45A is fitted in a seal ring 47 fitted in the mounting hole 7A of the pump body 4, and is mounted on the upper surface 4a of the pump body 4. Also, the mounting member 4
5 is connected to the pump body 4 by bolts 48.

The motor 3 has a motor main body 50 and an output shaft 51 projecting from the motor main body 50 in the axial direction. The output shaft 51 is provided on the side where the output shaft 51 protrudes. Tamo
The reduced-diameter step portion 50A of the tar body 50 is fitted into the large-diameter hole portion 46A of the through hole 46 of the mounting member 45, and is mounted on the upper surface of the mounting member 45. The motor body 50 is mounted on the mounting member 45 with bolts (not shown). At this time, the key portion 52 of the output shaft 51, which has a substantially long cross-section and protrudes from the lower surface 51a of the output shaft 51 through the through hole 46 of the mounting member 45, fits into the long hole 41 of the transmission member 40. The lower surface 51a of the output shaft 51 is
Contacting the upper surface 41a of the
20 is positioned on the bottom side of the recess 7. This allows
In accordance with the rotation of the output shaft 51 of the motor 3, this rotation is transmitted to the rotor 20 via the transmission member 40, and
20 is rotated. Reference numeral 53 denotes a seal member, which is a small-diameter hole portion 46B of the through hole 46 of the mounting member 45.
The cylindrical portion 54 provided at the center portion is externally fitted to the output shaft 51, and together with the seal ring 47, the recess 7 of the pump body 4 is sealed from the upper portion of the pump 4. .

Here, FIG. 2 and FIG.
Is the rotor 20 and the piston 2 via the support member 30.
5 shows a structure to be attached to the apparatus, and will be described in detail below with reference to FIGS.

As shown in FIG. 4A, the support member 30 is made of a strip-shaped metal plate, and has a shape in which a side plate portion 30A, a base portion 30B and a side plate portion 30C are continuously bent in a C-shape. The base 30B is attached to the base 30B from this width direction.
Holding portions 31 and 32 are provided to extend in the opposite side to the side plate portions 30A and 30B.
An engaging portion 33 that bends from the upper end toward the holding portion 32 is integrally formed. The holding parts 31 and 32 are side plates 3
0A and the side plate 30B extend in parallel. In addition, a hole 34 penetrating in the vertical direction is provided at the center of the base 30B. As shown in FIG. 4B, a stop portion 34A protruding radially inward is provided in the hole 34. Are formed at predetermined intervals.

The shoe 35 is provided on the base 30B of the support member 30.
And an arcuate surface is formed on the side facing the ball bearing 36, and a roll is formed on the opposite side of the arcuate surface.
A hollow portion 35A that opens to face the outer periphery of the heater 20 is formed. The shoe 35 is fitted between the holding portions 31 and 32 of the support member 30 such that the hollow portion 35A is concentric with the hole 34 of the base 30B of the support member 30.
Further, the engaging portion 33 of the holding portion 31 is the step portion 35 of the shoe 35.
a. Thereby, the shoe 35 is engaged with the holding portions 31 and 32 to regulate the axial direction of the rotor 20 and the engaging portion 33 of the holding portion 31 to restrict the movement in the radial direction. You. The piston 25 is incorporated in the support member 30 in which the shoe 35 is incorporated. The piston 25 is fitted into the hollow portion 35A of the shoe 35 by passing the head 27 side through the hole 34 of the support member 30. At this time, the stop portion 34A of the hole 34 of the support member 30
The head 25 of the piston 25 is engaged with a groove 26 a provided over the circumference of the shaft portion 26, and
Is in contact with the bottom surface 35b of the hollow portion 35A.

Next, in the assembly 60 in which the shoe 35 and the piston 25 are incorporated in the support member 30, the piston 25 of the assembly 60 is fitted into the cylinder hole 22 from outside the diameter of the rotor 20. At the same time, each of the side plates 30A and 30C of the support member 30 is elastically sandwiched between the side plates 30A and 30C by extending the space between the side plates 30A and 30C from a direction perpendicular to the axial direction of the cylinder hole 22. ,
It is incorporated in the printer 20. Thereby, the rotor-2
0 of the support member 30 elastically engaged with the peripheral surface of the support member 30
0A and 30C exert a spring function of urging the shoe 35 incorporated in the base 30B of the support member 30 to the inner race 37 of the ball bearing 36 in the radial direction of the rotor 20. Become.

The rotor 20 incorporating the assembly 60 is rotatably fitted around the outer periphery of the pintle 10 as shown in FIG.
Engagement of with being positioned so as to be positioned in space in a B-demarcated by the in-Nare over scan 37 of the rotor 20 and the ball bearing 36, the side plate portion 30A of the shoe 35 the support member 30, and 30C and the rotor 20 The inner race 37 of the ball bearing 36 is formed by the above-described spring function.
It is urged against the inner peripheral surface. Thereby, the motor 3
Is inactive, that is, even when the rotor 20 is not rotating, the shoe 35 is always
It is possible to abut the to In'nare scan 37 inner surface.

In such a configuration, when the motor 3 of the pump device 1 is operated to rotate the output shaft 51, this rotation is transmitted to the rotor 20 via the transmission member 40,
The rotor 20 rotates. Hydraulic fluid is supplied from a pipe (not shown) into the recess 7 through the suction port 13.
It is led from the upper inflow port to the inflow path 11 of the pintle 10 opening into the cylindrical portion 23. And the rotor
When one of the cylinder holes 22 communicates with the inflow passage 11 due to the rotation of the piston 20, the centrifugal force due to the rotational movement of the rotor 20 and the side plate portions 30A, 30C of the support member
Due to the urging force of the above-mentioned spring function, the shoe 35 comes into contact with the inner peripheral surface of the inner race 37 of the ball bearing 36 and moves radially outward of the rotor 20 while increasing the volume of the pressure chamber A. Therefore, the working fluid is sucked into the pressure chamber A. In this process, as the piston 25 moves, the support member 30 reduces the distance between the side plate portions 30A and 30C while reducing the rotor 20 position.
The peripheral surface slides outward in this radial direction.

Next, the cylinder hole 22 is blocked from the inflow path 11 by the peripheral surface of the rotor 20, and the rotor-2 is closed.
The eccentric rotational movement of the cylinder bore 22 and the bearing 36 gradually moves the piston 25 on the cylinder hole 22 side supplied with the hydraulic fluid in the radial direction of the rotor 20.
The volume of the pressure chamber A is reduced by the movement of the piston 25, and the hydraulic fluid in the pressure chamber A is pressurized. In this process, the support member 30 slides in the radial direction on the peripheral surface of the rotor 20 while widening the interval between the side plates 30A and 30C.

When the rotor 20 further rotates and the cylinder hole 22 communicates with the outflow passage 11, the pressurized hydraulic fluid is
It flows into the outflow channel 11 and is supplied to the check valve 14. At this time, the check valve 14 opens when the hydraulic fluid reaches a predetermined pressure, and is sent out from the discharge path 15 to the accumulator of the vehicle brake system through a pipe (not shown).

In this manner, the pump device 1 reciprocates the piston 25 accommodated in the cylinder hole 22 by the eccentric rotation of the rotor 20 and the ball bearing 36, thereby sequentially sucking and operating the hydraulic fluid. The operation of pressurizing is repeated, whereby the working fluid is stored in the accumulator.

According to the above-described embodiment, the movement of the rotor 35 in the axial direction and the radial direction of the rotor 20 is restricted by the holding portions 31, 32 and the engaging portion 33 of the support member 30. And is held by the support member 30.
The support member 30 to which the 35 is attached is connected to the piston 25 by engaging a stop 34A of a hole 34 provided in the base 30B with a groove 26a of a shaft 26 of the piston 25. Since the side plate portions 30A and 30C are elastically supported on the outer periphery of the rotor 20 so as to be movable in the radial direction of the rotor 20, even when the pump device 1 is not operated, it may receive vibration from outside. , 35 can be urged against the inner surface of the inner race 37 of the ball bearing 36 without falling off the piston 25 and displacing it.

The means for attaching the support member 30 to the outer periphery of the rotor 20 of the above-described embodiment is merely an example.
For example, with the side plate portion 30A, 30 C of the tip provided keyway from the support member 30, provided with a key for engagement with the key groove on the outer periphery of the rotor 20, the side plate portion 30A, 30 C of the support member 30 rotor When the key groove 20 is brought into contact with the peripheral surface of the shoe 20, the key groove
The movement of the rotor 20 in the axial direction may be further suppressed.

Also, as shown in FIG.
It the cash forte to al formation, or coiled spring as the wire
May be formed .

[0029]

As described above in detail, according to the pump device of the present invention, the spring for urging the shoe interposed between the stator and the piston toward the stator is formed on the outer periphery of the rotor.
Each piston in the space defined between
The rotor is arranged independently, and the rotor
Because of being supported on the outer periphery, falling and displacement of the shoe
In order to prevent this, it is not necessary to form a step portion for supporting the spring in the cylinder hole or to incorporate a member for supporting the spring, and it is possible to form the cylinder hole with a uniform inner diameter.

Further, regulating Shinano axial movement, and the radial against the shoe of the rotor by a holding portion of the spring
Then, connect the shoe and the piston via the base of the spring,
A pair of plate-like sides provided on the spring allows the shoe and
To support the portion projecting from the emission of the cylinder bore in the rotor
The shoe may fall off from the piston or stay in position even when the pump device is
This can be prevented more reliably .

[Brief description of the drawings]

FIG. 1 is a drawing showing a pump device as one embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a view taken in the direction of arrows BB in FIG. 2;

FIG. 4 is a drawing showing details of a support member (spring) in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pump apparatus 20 Rotor 22 Cylinder hole 25 Piston 30 Supporting member (spring) 35 Shue 36 Ball bearing (Stator)

Claims (2)

(57) [Claims] 1. A rotor having a plurality of radially extending cylinder holes, a stator eccentrically provided on an outer peripheral side of the rotor, and a rotor slidably fitted in each of the cylinder holes. A piston reciprocating by relative rotation with the stator, a shoe interposed between the piston and the stator, and engaging with the piston
In the pump apparatus having a spring which biases the shoe toward the stator together with the piston, the spring is disposed in the cavity which is defined between the outer periphery and the stator of the rotor shall And said shoe
An engaging base and the row protruding from both ends of the base.
A pair of side portions abutting the outer peripheral surface of the
Pump device provided independently for each ton . 2. The spring according to claim 1, wherein the pair of side portions has a plate shape.
The pump device according to claim 1 , wherein the base has a holding portion that holds the shoe with respect to the piston.