JP2505099Y2 - Radial piston pump - Google Patents

Description

TECHNICAL FIELD The present invention relates to a radial piston pump used in a hydraulic control device or the like.

2. Description of the Related Art As shown in FIG. 7, a housing (stator) 02 is fixed in a pump casing 01, a pintle 03 is fixed in the housing 02, and the outer periphery of the pintle 03 is a cylinder together with the housing 02. Cylinder body
04 is rotatably fitted, and a plurality of pistons 05 that reciprocate in the radial direction are mounted in its inner chamber, and its sliding position is rotatably mounted in the housing 02 via rollers 017. The piston guide ring 06 is provided so as to be eccentric with respect to the axis of the pintle 03.

When the cylinder body 04 is rotated by the drive shaft 07, the reciprocating motion of the piston 05 causes oil to flow from the inflow port 08 of the casing 01 through the housing 02 and the cylinder body 04 to the communication port 09 formed in the housing 02, Inflow passage 010 formed in pintle 03, same inflow port 011 and cylinder body 04
Of the oil that has flowed into the inner chamber of the pintle 03 from the outflow port 012 formed in the pintle 03, the outflow passage 013 provided in the same axial direction as the inflow passage 010 in the pintle, and the connection in the housing 02. It flows through the passage 014 to the annular flow passage 015 formed between the casing 01 and the housing 02, and flows out from the annular flow passage 015 to the outside of the casing 01.

A seal ring 016 is attached between the casing 01 and the housing 02 on both sides of the annular flow path 015.
(See Japanese Patent Laid-Open No. 61-61985) Problems to be Solved by the Invention In the radial piston pump shown in FIG. 7, the cylinder body 04 is centered on the fixed pintle 03, and the inside of the housing 02 is Since it rotates via the piston guide ring 06 and the roller 017, there is little sliding friction,
Although the mechanical efficiency is high, the sealability of the seal ring 016 on the right side of the pair of left and right seal rings 016 that seals the annular flow channel 015 is reduced, and the high pressure oil on the pump discharge side in the annular flow channel 015 is reduced. When flowing into the sealed space between the inner surface of the right side portion of the pump casing 01 and the right end surfaces of the housing 02 and the pintle 03,
The housing 02 and the pintle 03 are strongly pushed to the left by the high-pressure oil, and the drive shaft 07 is strongly pushed accordingly, and the pump drive mechanism is damaged.

Further, due to the large hydraulic pressure acting on the end surfaces of the housing 02 and the pintle 03 and the difference in the end areas of both members, a displacement occurs in the relative rotational axis position between the housing 02 and the pintle 03, and the displacement is connected to the outflow passage 013 on the pump discharge side. The connection with the passage 014 does not match, the outflow passage 013 is closed, the hydraulic pressure of the pressure oil in the cylinder hole of the cylinder body 04 rises significantly, and the cylinder body
04, piston 05, piston guide ring 06, etc. may be destroyed due to excessive force.

MEANS TO SOLVE THE PROBLEM AND ACTION The present invention relates to an improvement of a radial piston pump that overcomes such difficulties, and a casing having a suction port and a discharge port, and a housing fixed to the casing.
A pintle fixed to the housing and having an inflow path and an outflow path, a cylinder body rotatably fitted in the pintle, and a slidable fitting in a cylinder hole radially provided in the cylinder body. A piston, a piston guide ring disposed eccentrically with respect to the axis of the pintle in the housing, abutting against the tip of the piston to regulate the piston position, and a drive device for rotating the cylinder body. A radial piston pump configured such that an intake / exhaust chamber formed inside a piston of a hole moves on an inflow port and an outflow port connected to an inflow path and an outflow path of the pintle in accordance with rotation of a cylinder body. The other end of the flow path in the housing, one end of which is connected to the outflow passage of Two seal rings are respectively provided on the casing and the housing on both sides of the annular groove, and a relief passage communicating the end face of the outlet side housing and the end face of the inlet side housing is provided through the housing. It has been done.

Since the present invention is configured as described above, of the two seal rings located on both sides of the annular groove, the seal ring near the end face of the outflow passage side housing loses the sealing property and is pressurized to a high pressure by the pump. Even if the generated outflow pressure oil flows into the space between the inner surface of the casing and the end surface of the housing on the outflow passage side from the annular groove, the pressure oil in the space flows through the relief passage that penetrates the housing and flows in the inflow fluid. The housing and pintle are returned to the inflow passage adjacent to the end face of the roadside housing, and the axial hydraulic pressure does not act on the housing and the pintle. There is no relative displacement in the axial direction due to the difference in force, and as a result, blockage of the outflow passage is avoided and abnormal rise in outflow pressure is prevented. It is.

Examples Examples will be described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a cylindrical pump casing, which is provided with a suction port 2 and a discharge port 3. The suction port 2 communicates with an oil tank (not shown) and the discharge port 3 communicates with an accumulator or the like of an antilock brake device. ing.
An annular groove 4 connected to the discharge port 3 is provided on the inner peripheral surface of the portion where the discharge port 3 is formed.

A housing 5 is fitted inside the casing 1,
It is fixed to the casing 1 by a knock pin 6.
The housing 5 is composed of a small diameter portion 5a and a large diameter portion 5b, and an annular chamber 7 is formed inside the large diameter portion 5b for accommodating a cylinder body 13 which is a rotor.

The casing 1 is provided on the outer periphery of the small diameter portion 5a of the housing.
Concave grooves 8 are formed on both sides of the annular groove 4 in the pintle axial direction,
A seal ring 9 is attached to the groove 8 so that the casing 1 and the housing 5 are sealed. Further, as shown in FIG. 2, a channel 10 communicating with the annular groove 4 is provided in the small diameter portion 5a, and the channel 10 is connected to a channel 12 provided in a pintle 11 described later.

In addition, inside the small diameter part 5a of the housing, the pintle 11
Is fixedly fitted, the cylinder body 13 is rotatably fitted in the pintle 11, and is housed in the annular chamber 7 as described above.

As shown in FIG. 3, four pistons 14 are fitted in the cylinder hole of the cylinder body 13 so as to be slidable in the radial direction at intervals of 90 degrees, and the piston 14 is rotated by the centrifugal force of the cylinder body 13 during rotation. A piston guide ring 16 which is moved outwardly and whose head 14a is mounted eccentrically with respect to the axis of the pintle 11 through the roller bearing 15 in the large diameter portion 5b of the housing.
By contacting the inner surface of the, the position at the time of rotation is regulated. The number of pistons 14 is not limited to four and may be plural. The portion of the cylinder hole of the cylinder body 13 that accommodates the piston 14 formed inside the piston 14 constitutes an oil suction / discharge chamber 17. Also,
The piston head 14a is formed in a spherical shape, and the inner surface of the piston guide ring 16 that abuts on the piston head 14a is also curved in the pintle axial direction so as to fit the piston head 14a.

As shown in FIG. 4, an annular engaging portion 19 having four notched portions 18 cut at equal intervals is integrally formed at one end of the cylinder body 13.

On the other hand, it is projected at a symmetrical position and engages with the cutout portion 2
A disc portion having a plurality of projecting portions 20, a notch portion 21 that is partially cut in parallel with the projecting portion 20, and a locking hole 22 for inserting and fixing a tip projecting piece 26 of a motor drive shaft 25 in the center. A flat coupling 24 having 23 is provided, the motor drive shaft 25 is fixed to the coupling 24, and the protrusion 20 is fixed to the cylinder body.
While engaging with the notch portion 18 of the disc 13, the disc portion 23 is engaged with the annular engaging portion 19
The rotation of the motor drive shaft 25 is transmitted to the cylinder body 13 via the coupling 24 by being fitted into the cylinder body 13. Then, as described above, the disc portion 23 is the annular engaging portion.
When fitted in 19, the oil passes between the annular engagement portion 19 and the notch portion 21 of the disc portion 23 and flows into the inflow passage 35 (filter
34).

Further, an annular groove 27 is formed on the outer periphery of the pump casing 1 corresponding to the suction port 2 as shown in FIG. 5, and four oil supply holes 29 communicating from the groove 27 to the central hole 28 are provided.
Donut-shaped oil supply rings 30 provided at equal intervals are fitted. Then, the cylinder body 13 is fitted into the central hole 28 so that the outer peripheral surface 31 has a slight gap.

A friction reducing member 54 is provided on either side of the sliding portion between the cylinder body 13 and the small diameter portion 5a of the housing in order to reduce sliding friction resistance.

Next, as shown in FIG. 1, in the pintle 11, an oil inflow passage 35 into which a filter 34 is fitted and inserted at an end portion on the coupling 24 side.
Are formed. As shown in FIG. 6, the filter 34 includes an annular portion 36 having an outer diameter substantially equal to that of the inflow passage 35 of the pintle 11, a circular disc portion 37 having a smaller diameter than that, and these annular portions 36 and 37. An oil filtering mesh 39 is stretched inside a frame integrally formed by a connecting portion 38 having the same outer diameter as that of the annular portion 36. The filter 34 is connected to the inflow passage 35 of the pintle 11.
When the slide 38 is slid and inserted, the oil that has flowed in from one end of the pintle 11 flows from the central hole 36a of the annular portion 36 through the mesh 39 and out of the outer periphery of the disc portion 37. .

As shown in FIG. 2, the pintle 11 communicates with the outer periphery of the disk portion 37 of the filter 34, that is, the inner end of the inflow path 35, and corresponds to the rotational position of the intake / exhaust chamber 17 of the cylinder body 13. An inflow port 40 opening to the is provided.

An outflow port 41 is provided on the opposite side in the circumferential direction of the shaft with respect to the inflow port 40, and at a position slightly apart in the axial direction, and the outflow port 41 extends in the pintle 11 on the opposite side to the inflow path. Connected to the outflow channel 42. And the outflow path
42 is composed of a small diameter flow path 42a and a large diameter flow path 42b, and a one-way valve 43 is provided in the outflow path 42. One-way valve 43 is a large diameter passage
A ball 44 that is inserted into 42b to open and close the small diameter passage 42a, a spring 45 that supports the ball 44 in pressure contact with the end of the small diameter passage 42a, a support plate 46 of the spring 45, and an end portion of the pintle 11. The one-way valve mounting hole 47 from the outlet to the outflow passage 42 is drilled, and the spring support plate 46 is fixed to the mounting hole 47 for mounting. A seal member 48 is interposed and sealed between the support plate 46 and the one-way valve mounting hole 47. (First
(Fig.) The end portion of the outflow passage 42 is connected to the flow passage 12 that is formed in the pintle 11 in the radial direction. This flow path 12 is connected to the flow path 10 in the housing small-diameter portion 5a as described above.

Further, a relief passage 50 axially penetrating from the housing end surface 49 of the pintle on the outflow passage side is provided in the small-diameter portion 5a of the housing.
Through the gap between the inner surface and the outer surface of the cylinder body 13, that is, the one side surface 32 of the cylinder body 13 and the notch 33 on one side surface of the oil supply ring 30, the central hole 28 of the oil supply ring 30 is interposed.
And communicates with the suction port 2 side.

A motor body 51 is fitted to the pump casing 1 with a spigot, and a seal portion 52 is provided between the two. 53 is a bearing of the motor drive shaft 25.

Since the present embodiment has such a configuration, the motor drive shaft
When the cylinder main body 13 rotates via the coupling 24 by the rotational drive of 25, the piston 14 in the cylinder main body 13 is sucked and discharged while its position is regulated by the piston guide ring 16 that rotates together with the rotation of the cylinder main body 13. It reciprocates in the chamber 17 in the radial direction. By this reciprocating movement, oil is sucked from the suction port 2 of the pump casing 1, and the oil supply hole 29 of the oil supply ring 30, the central hole 28, the gap between the inner surface of the motor body 51 and the side surface of the coupling 24, and the notch of the coupling 24. Department
21,18 The oil is sucked into the intake / exhaust chamber 17 of the cylinder body from the inflow port 40 of the pintle 11 via the filter 34 fitted in the inflow passage 35 of the pintle 11, and the oil stored in the intake / exhaust chamber 17 is discharged from the outflow port 41. After the reverse flow is prevented by the one-way valve 43, the flow path 12 and the flow path 12, 1
0, it is pressure-fed from the discharge port 3 to the outside of the casing 1 via the annular groove 4.

If the seal ring 9 between the casing 1 and the small-diameter portion 5a of the housing or the seal member 48 of the one-way valve mounting portion is damaged and loses its sealing function, the high pressure oil causes the casing 1
Although the high-pressure oil leaks to the contact portion between the inner surface and the end surface 49 of the small-diameter portion 5a of the housing, this high-pressure oil is opened from the housing end surface 49 and extends from the relief passage 50 bored in the housing 5 to the housing as shown by a dotted line. 5 into the annular chamber 7 between the cylinder body 13 and the space between the outer peripheral surface of the cylinder body 13 and the piston guide ring 16,
It can flow from the gap between the one side surface 32 of 13 and the one side cutout 33 of the oil supply ring 30 to the suction port 2 through the central hole 28 and the oil supply hole 29 of the oil supply ring 16, and as a result, the housing 5
Since no rightward force acts on the pintle 11 and the coupling 24 and the motor drive shaft 25 are strongly pressed to the right and the motor is not damaged, the housing 5
Flow path due to relative axial displacement between the pintle and pintle 11
The communication between 10 and the flow path 12 is not interrupted, the abnormal rise of the pressure oil in the cylinder body 13 is prevented, and the pump is prevented from being broken.

As described above, in the present invention, the sealing property of the seal ring near the end face of the outflow passage side housing is impaired, and the outflow pressure oil pressurized to a high pressure by the pump flows from the annular groove to the inner surface of the casing and the outflow passage side. Even if it flows into the space between the housing and the end face, no axial hydraulic pressure acts on the housing and pintle, so that the housing and pintle are not pushed axially and the drive mechanism is damaged. There is no relative axial displacement due to the difference in the axial forces of the housing and pintle, and as a result,
The blockage of the outflow passage is avoided, the outflow pressure is prevented from rising abnormally, and the pump is prevented from being broken.

[Brief description of drawings]

1 is a longitudinal sectional view of a radial piston pump according to the present invention, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, FIG. 3 is a sectional view taken along the line III-III, and FIG. Is an exploded perspective view of the coupling device, FIG. 5 and FIG.
FIG. 7 is a perspective view of the filter, and FIG. 7 is a longitudinal sectional view of a conventional radial piston pump. 1 ... Casing, 2 ... Suction port, 3 ... Discharge port, 4 ...
… Annular groove, 5… Housing, 6… Dowel pin, 7…
… Annular chamber, 8… Concave groove, 9 …… Seal ring, 10 …… Flow path, 11 …… Pintle, 12 …… Flow path, 13 …… Cylinder body, 14 …… Piston, 15 …… Roller bearing, 16 ……
Piston guide ring, 17 …… Suction / exhaust chamber, 18 …… Notch,
19 …… Annular engagement part, 20 …… Projection part, 21 …… Notch part, 22…
… Locking hole, 23 …… Disc part, 24 …… Coupling, 25 ……
Motor drive shaft, 26 ... Tip projection, 27 ... Annular groove, 28 ...
… Center hole, 29 …… Oiler hole, 30 …… Oiler ring, 31 …… Outer peripheral surface, 32 …… 1 side surface, 33 …… 1 side notch, 34 …… Filter, 35 …… Inflow passage, 36 …… Ring part, 37 …… Disk part, 38
...... Coupling, 39 ...... Mesh, 40 …… Inflow port, 41…
… Outflow port, 42 …… Outflow path, 43 …… One way valve, 44 ……
Ball, 45 ... Spring, 46 ... Support plate, 47 ... One-way valve mounting hole, 48 ... Seal member, 49 ... Housing end face, 50 ... Relief passage, 51 ... Motor body, 52 ... Seal Part, 53 ... Bearing, 54 ... Anti-friction member

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kazutoshi Tajima, 1-4-1, Chuo, Wako-shi, Saitama, Honda R & D Co., Ltd. In-company (72) Inventor Akira Yamanaka 840 Kokubu, Ueda-shi, Nagano Nissin Kogyo Co., Ltd. In-company (56) References JP 61-61985 (JP, A) SAI 64-13278 (JP, U) )

Claims (1)

(57) [Scope of utility model registration request] 1. A casing having a suction port and a discharge port, a housing fixed to the casing, a pintle fixed to the housing and having an inflow path and an outflow path, and a cylinder rotatably fitted to the pintle. A body, a piston slidably fitted in a cylinder hole provided in a radial direction in the cylinder body, and an eccentric arrangement with respect to the axis of the pintle in the housing, and abutting on the piston tip end portion. A piston guide ring for restricting a piston position and a drive device for rotating the cylinder body are provided, and an intake / exhaust chamber formed inside the piston in the cylinder hole has an inlet passage and an outlet passage of the pintle as the cylinder body rotates. A radial piston pump configured to move over an inflow port and an outflow port connected to the Two seal rings are located on both sides of an annular groove that communicates the other end of the flow path in the housing, one end of which is connected to the outflow passage of A radial piston pump, wherein a relief passage, which is interposed and communicates the end face of the outflow passage side housing and the end face of the inflow passage side housing, is provided through the housing.