JPS60247069A - Fluid pump - Google Patents

Abstract

PURPOSE:To reduce abrasion at the bearing section by rotating the bearing section where the fork section of locker arm will contact. CONSTITUTION:The bearing section 12c is supported rotatably by a piston rod 12b. A spring 16 is contacted resiliently between the bearing section 12c and the piston rod 12b. Said spring 16 will function as an unilateral clutch for rotating the bearing section 12c only unilaterally. The fork section 13a of locker arm 13 is contacting against the bearing section 12. The fork section 13a is formed into thin and wide portions 13a2. The bearing section 12 is rotated by driving the locker arm 13 through function of spring 16 and the different width of fork section 13a.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a sliding piston type or diaphragm piston type that is installed in a vehicle, etc., and is driven by a driving means such as an engine to function as a vacuum pump, a fuel pump, etc. Relating to fluid pumps.

[Prior art]

In general, this type of fluid pump is
As shown in Publication No. 66, an actuating piston is reciprocatably assembled inside the housing body to form a pump chamber on one side of the actuating piston, and a support provided in the rond part of the actuating piston. The rocker arm supports the swinging end portion of the rocker arm that swings due to the rotation of the pump drive shaft, and the swinging action of the rocker arm generates negative pressure or positive pressure in the pump chamber.

[Problem that the invention seeks to solve]

By the way, in this type of fluid pump, the swinging end of the rocker arm is supported in line contact with the supporting part of the operating piston at the same location, and when the rocker arm swings, there is a slight slippage between them due to relative slippage between the two. The bearing portion is repeatedly subjected to friction and is damaged by wear in the swinging direction. As a result, the maximum movement position of the working piston, such as the top dead center, will change, and the set vacuum level and other pump functions will deteriorate, and there is a risk of interference between the piston and the pump chamber components when the working piston moves to its maximum. be. To deal with this, measures are taken to reduce wear by applying lubricating oil to the bearing.
Such measures cannot sufficiently prevent the wear damage described above.

[Means for solving problems]

In order to solve this problem, the present invention provides a fluid pump of this type, in which the support part is provided on the outer periphery of the rod part so as to be rotatable in the circumferential direction thereof, and the swinging end of the rocker arm is brought into contact with the support part. The surfaces are different on both sides in the longitudinal direction of the rocker arm with the rod portion as a reference so that the support portion is rotated by the rocking motion of the rocker arm, and between the support portion and the rod portion. A clutch means is provided to restrict rotation of the support portion in one direction.

[Action/effect of the invention]

As a result, in the present invention, when the rocker arm swings, forces of different magnitudes in the orthogonal direction act on the rond portion on both sides of the rod portion of the support portion of the operating piston as a reference, and this acting force is The support part can be rotated around the axis of the rod part.

Therefore, the sliding contact portion of the swinging end of the rocker arm with respect to the support portion gradually shifts, thereby reducing wear and tear on the support portion. Therefore, deterioration of pump function and interference between the operating piston and each component due to this wear and tear are prevented.

Further, in the present invention, a clutch means is particularly provided between the bearing part and the rod part for restricting the rotation of the bearing part in one direction. For this reason, even though forces act in different directions on the bearing when the rocker arm reciprocates,
Due to the action of the clutch means, the bearing portion rotates intermittently in a constant direction without reciprocating. Therefore, wear and tear on the support portion can be reliably reduced.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a sliding piston type vacuum pump according to a first embodiment of the present invention.

In the vacuum pump 10, a housing main body 11 is assembled to a cylinder nozzle and a handlebar of an engine (not shown) in a vehicle, and an operating piston 12 is disposed inside the housing main body 11. In addition, the lower housing ll constituting the housing main body 11
A rocker arm 13 is disposed at a.

The actuating piston 12 includes a disk-shaped piston part 12a, a rod part 12b attached to the approximate center of the piston part 12a and extending downward, and a support part 12C that is fitted into the lower end of the rotor 112b (7) to prevent it from coming out. It consists of a piston part 12a
is airtightly and slidably inserted into the cylinder portion 11b of the lower housing lla, and the support portion 12C fitted into the rod portion 12b is supported slidably in the axial direction at the bottom of the lower housing lla. Housing body 1
■Assembled inside. The operating piston 12 is biased upward by a compression spring 14 whose lower end is engaged with the stepped portion of the lower housing lla, and the supporting portion 1
The fork part 13a, which is the swinging end of the rocker arm 13, is supported by the outward flange part 12d of the rocker arm 13, and the roller part 13b provided at the other end of the rocker arm 13 elastically abuts on the outer periphery of the eccentric cam C1. I'm letting you do it. In this state, the actuating piston 12 forms a pump chamber R1 on the upper surface side of the piston portion 12a. The eccentric cam CI is mounted on the camshaft C2 so as to be integrally rotatable, and is rotated in the direction of the arrow shown in the figure by the drive of the engine, thereby swinging the fork portion 13a of the rocker arm 13 in the vertical direction.

The pump chamber R1 is intermittently communicated with a suction chamber R2 provided in the upper part of the upper housing IIC via a suction check valve 15a, and is intermittently communicated with a discharge chamber R3 via a discharge check valve 15b. .

Therefore, the support part 12C is attached to the outer periphery of the rod part 12b so as to be rotatable around its axis, and both of these parts 12
As shown in FIGS. 2 to 4, a coil spring 16 made of strip-shaped spring steel is interposed between the lower ends of the coil springs 12B and 12C. Most of the coil spring 16 is attached to the support portion 1
2 C, is in elastic contact with the inner periphery of C, and its lower end is in elastic contact with the outer periphery of the rod portion 12b,
When the support portion 12C rotates in the coil winding direction, it contracts to allow the rotation, and when it rotates in the opposite direction to the coil winding direction, it expands to restrict the rotation.

That is, the coil spring 16 functions as a one-way clutch.

On the other hand, as shown in FIG. 5, the fork portions 13a of the rocker arm 13 are formed to have different widths on both sides of the rocker arm 13 in the longitudinal direction with respect to the rod portion 12b. Therefore, the horizontal force acting on the support part 12C is larger in the wide part 13a2 than in the narrow part 13a1, and as a result, when the rocker arm 13 swings downward, the support part 12c rotates in the direction of the arrow in FIG. do.

In the vacuum pump 10 configured in this manner, when the eccentric cam CI rotates due to engine drive and the rocker arm 13 repeatedly swings in the vertical direction, the actuating piston 12 acts as an upward biasing action on the compression spring 14. The rocker arm 13 moves up and down repeatedly by pushing the rocker arm 13 downward.

During this period, when the working piston 12 moves upward, the suction check valve 15a closes, and the discharge check valve 15b opens, and the air in the pump chamber R1 is discharged through the discharge chamber R3. In addition, when the operating piston 12 moves downward, the pump chamber R
1, the suction check valve 15a opens and the discharge check valve 15b closes, applying the negative pressure generated in the pump chamber R1 to a negative pressure actuator such as a brake booster through the suction chamber R2.

By the way, in this embodiment, the support part 12c of the actuating piston 12 is attached to the outer periphery of the rod part 1.2b so as to be rotatable in the circumferential direction thereof, and the fork part 13a of the rocker arm 13 is attached to the narrow part 13a1 and the wide part 13a1. It is formed in the portion 13a2. Therefore, when the rocker arm 13 swings in the vertical direction, horizontal forces of different magnitudes act on both sides of the support portion 12C with the rod portion 12b as a reference, causing the support portion 12C to move around the axis of the rod portion 12b. Rotate it. In this case, the force acting on the support portion 12c is in opposite directions when the rocker arm 13 moves upward and downward, or there is a coil spring 16 that functions as a one-way clutch between the rod 12b and the support portion 12c. Because it is equipped with
The support portion 12c always rotates in the direction of the arrow in FIG. 5 only when the mouth/lock arm 13 swings downward. As a result, the sliding contact portion of the fork portion 13a with respect to the support portion 12C gradually shifts, and the wear and tear of this portion is greatly reduced compared to the conventional case where the sliding contact portion is constant. Therefore, according to this embodiment, the clearance between the upper surface of the piston part 12a at the top dead center of the working piston 12 and the lower surface of the F section housing IIC does not become negative, and the set function of the vacuum pump 10 can be maintained. It can be maintained for a long period of time and its reliability can be significantly improved, and interference between the upper surface of the piston portion 12a and the lower surface of the upper housing IIC at the top dead center of the working piston 12 can be prevented.

FIG. 6 shows a diaphragm piston type vacuum pump according to a second embodiment of the present invention. The vacuum pump 20 is the same as the vacuum pump 10 of the first embodiment, except for the fact that a diaphragm piston is used as the operating piston 22, the shape of the housing body 21 to which the operating piston 22 is attached, the assembly means, etc. It is composed of

The actuating piston 22 consists of a diaphragm 22a on a disc, a rod part 22b attached to the center of the diaphragm 22a, and a support part 22C fitted into the lower end of the rod part 22C to prevent the diaphragm 22a from coming off. It is assembled via a diaphragm dish 22d and a spring retainer 22e, which are sandwiched from the diaphragm dish 22d. In such an operating piston 22, the outer peripheral edge of the diaphragm 22a is sandwiched between the lower housing 21a and the upper housing 21b, and the supporting portion 22C of the diaphragm 22a is supported slidably in the axial direction at the bottom of the lower housing 21a. 21
It is assembled inside.

In this operating piston 22, a support portion 22C similar to the support portion 12c of the first embodiment is connected to the rod portion 22b.
The fork portion 23a of the rocker arm 23 is supported on the upper surface of the support portion 22C, and the compression spring 24
The pump chamber R1 is intermittently connected to the suction chamber R2 via the suction check valve 25a, and the discharge check valve Discharge chamber R3 via valve 25b
The fork portion 23a is similar to the vacuum pump 10 of the first embodiment in that the fork portion 23a has a narrow portion and a wide portion.

Therefore, the vacuum pump 20 in this second embodiment
Also, the vacuum pump 10 in the first embodiment
It operates in the same way and produces the same effects.

FIG. 7 shows a first modification of the clutch means and the support portion that supports the rocker arm 13. In FIG. In the actuating piston 32 shown in this first modification, a flange member 32d is fitted and fixed to the lower end of the rod portion 32b, and a cap-shaped support portion 32C is attached to the flange portion.
are fitted from above. This support portion 32c is rotatably assembled in the circumferential direction to the rod portion 32b and the flange portion 4-(32d integral therewith),
A coil spring 36 shown in FIG. 8 is interposed between the inner circumference and the outer circumference of the flange portion of the flange member 32d. This coil spring 36 has one end locked to the outer periphery of the flange portion, elastically contacts the inner periphery of the support portion 32C, and contracts when the support portion 32C rotates in the direction of the arrow in FIG. 8 to prevent the rotation. It allows rotation, and when it rotates in the opposite direction, it expands and restricts the rotation. Therefore, even if such a modification is adopted in the vacuum pump of each of the above embodiments, the same effects as those of each of these embodiments can be achieved.

FIG. 9 shows a second variant of the bearing and clutch means. In the actuating piston 42 shown in this second modification, a flange member 42d is fitted and fixed to the lower end of the rod portion 42b, and a cap-shaped support portion 42 is mounted on the flange portion of the flange member 42d.
The fact that C is fitted is similar to the first modification, but the lower surface of this support portion 42c and the flange member 42 d
A spring member 46 shown in FIG. 10 is interposed between the upper surfaces of the flange parts. This spring member 46 is made of an annular plate with a spiral slit and has elasticity in the radial direction, and is partially locked onto the flange portion of the flange member 42d so that its outer periphery is inside the support portion 42C. It is in elastic contact with the periphery. The spring member 46 contracts when the support portion 42c rotates in the direction of the arrow in FIG. 10 to allow the rotation, and expands when the support portion 42c rotates in the opposite direction to restrict the rotation. Therefore, even if such a modification is adopted in the vacuum pump of the above embodiment, the same effects as those of each of the embodiments can be obtained.

FIG. 11 shows a modification of the rocker arm. In the rocker arm 33 of this modification, the swinging end 3 corresponding to the fork portion 13a of the rocker arm 13 is
3a corresponds to the wide portion 13a2 and does not include the narrow portion 13al. Therefore, in the rocker arm 33, a horizontal force can be applied to only one side of the rod portion 12b with respect to the support portion 12C, and the narrow portion 13a
1, the support portion 12C can be rotated more favorably than the rocker arm 13 equipped with the rocker arm 13.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of a vacuum pump according to a first embodiment of the present invention, FIG. 2 is an enlarged vertical cross-sectional view of a rocker arm support portion of the same pump, and FIG. 3 is an arrow mark - ■ in FIG. 2.
4 is a perspective view of a coil spring as a clutch means, FIG. 5 is a partial plan view of the swinging end of the rocker arm in the same pump, and FIG. 6 is a second embodiment of the present invention.
A vertical cross-sectional view of the vacuum pump according to the embodiment, FIG. 7 is 0
．． 7. A partial vertical sectional view showing a first modification of the force-arm support; FIG. 8 is a plan view of a coil spring as a clutch means used in the modification; FIG. 9 is a second modification of the rocker arm support. FIG. 10 is a plan view of a spring member as a clutch means used in the modification, and FIG. 11 is a partial plan view of the swinging end of a modification of the rocker arm. Explanation of symbols 10.20...Vacuum pump, 11.21...
Housing body, 12, 22, 32.42... Working piston, 12a... Piston part, 22a -- Diaphragm, 12b, 22b, 32b, 42b... o,
, F part, 12c, 22c. 32c, 42c...Support part, 13,23.33...
Rocker arm, 13a, 23a... fork part, 3
3a... Swinging end. Applicant: Toyota Motor Corporation (1 other person) Agent: Patent attorney Teru Hase - Shiro 2 Figure 3 Mulberry Figure 4 J15 J16 Shoe JI7 Figure 8 '49 Shinobu No. 10,! 11λ

Claims (1)

[Claims] An operating piston is assembled inside the housing body so as to be able to reciprocate, forming a pump chamber on one side of the operating piston, and is oscillated by the rotation of the pump drive shaft at a support provided in the rond part of the operating piston. In the fluid pump, the rocker arm supports the swinging end of the rocker arm, and the swinging action of the rocker arm generates negative or positive pressure in the pump chamber. The rocker arm is provided rotatably in its circumferential direction, and the contact surfaces of the rocking end of the rocker arm with respect to the support part are different on both sides of the rocker arm in the longitudinal direction with respect to the rond part as a reference. A fluid pump, characterized in that the support part is rotated by a swinging action, and a clutch means is provided between the support part and the rond part for restricting rotation of the support part in one direction.