JPS59194087A - Fluid pump - Google Patents

Abstract

PURPOSE:To lubricate sufficiently between the rod guide section and the rod section by making a stepped hole and an oil hole in the bottom of housing body while forming the lower small diameter section of the stepped hole into an oil pump. CONSTITUTION:The outercircumference of the lower section of rod section 22a in an operating piston 20 is inserted rotatably into a receiving member 23 which is inserted into a bush 17b of a guide member 17 while a bottomed step hole 11g and an oil hole 11h are made in the bottom wall section 11f of the lower housing 11 to form the lower small diameter section 11g2 of the step hole 11g into an oil sump. Since oil in the oil sump is fed through up-down motion of an operating rod 22 between the innercircumference of bush 17b and the receiving member 23, lubrication between the guide member 17 and the receiving member 23 can be performed accurately resulting in effective prevension of abrasion and burning.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid pump, and more particularly, a working piston is assembled inside a housing body so as to be able to reciprocate in the axial direction, and a pump chamber is formed on one side of a piston portion of the working piston. The rod part of the actuating piston is connected to the swinging end of a rocker arm that swings due to the rotation of the pump drive shaft, and the swinging action of the rocker arm causes the actuating piston to reciprocate in the axial direction to open the pump chamber. This invention relates to a fluid pump that generates positive pressure or negative pressure.

In this type of fluid pump, not only a vertical (axial) force but also a horizontal (radial) force acts on the rod portion of the operating piston when the rocker arm swings. For this reason, when the fluid pump is a piston-type fluid pump, the piston portion is strained when the working piston reciprocates in the axial direction, which accelerates damage to the piston portion. Further, when the fluid pump is a diaphragm type fluid pump, the diaphragm deforms non-uniformly and local stress is generated, resulting in a decrease in durability. Moreover, during this time, the diaphragm dish that supports the diaphragm from the pump chamber side tilts, so it is necessary to lower the top dead center of the diaphragm piston by a predetermined amount in consideration of this tilting. The rate of change in volume of the pump decreases, reducing pump efficiency.

In order to deal with these problems, in this kind of fluid pump,
It has been proposed that a front guide portion is provided inside the housing body, and the rod portion of the actuating piston is supported slidably in the axial direction by the front guide portion. This results in
In such a fluid pump, the direction of movement of the rod portion is restricted in the axial direction when the actuating piston reciprocates. Therefore, in the case of a piston-type fluid pump, the piston portion is prevented from twisting, and damage to the piston portion is reduced. In addition, in a diaphragm type fluid pump, uneven deformation of the diaphragm is prevented and expansion of the diaphragm dish is prevented, thereby preventing a decrease in the durability of the diaphragm and a decrease in pump efficiency. . However, in such a fluid pump, a radial force acts on the rod portion of the operating piston, which tends to cause wear between the outer periphery of the rod portion and the inner periphery of the front guide portion, and seizure occurs between the two. There is a possibility that this may occur. For this reason,
It is required to sufficiently lubricate the sliding contact portion between the rod portion and the front guide portion of the operating piston to prevent wear, seizure, etc. between the outer and inner peripheries thereof.

In order to deal with this, one of the present applicants proposed a fluid pump in which the upper part of the rod part of the actuating piston is supported by the front guide part so as to be slidable in the axial direction. In a patent application filed on March 11, 1982, a mechanism for sufficiently lubricating the sliding contact parts of the machine was proposed.

Therefore, an object of the present invention is to provide a fluid pump in which the lower part of the rod part of an operating piston is supported by a front guide part so as to be slidable in the axial direction. The purpose is to lubricate the

In order to achieve such an object, the present invention provides a fluid pump such as a piston type or a diaphragm type as described above, in which the lower part of the rod part of the operating piston is moved in the axial direction by a front guide part provided in the lower part of the housing main body. A recess that is slidably supported and that the lower end of the rod portion of the actuating piston faces in a movable manner at the bottom of the housing main body, and a communication hole that extends downward from the bottom of the housing main body and communicates with the recess. The structure is characterized by the fact that the recess is formed in the oil reservoir.

As a result, in the present invention, the oil supplied into the housing body from the camshaft of the engine, which is the pump drive shaft, can be stored in the oil reservoir provided at the bottom of the housing body, and the oil can be stored in the oil reservoir provided at the bottom of the housing body. The oil stored in the oil reservoir can be supplied between the rod guide part and the rod part of the actuating piston by the splashing action of the lower end of the rod part. Therefore, according to the present invention, it is possible to sufficiently lubricate the space between the long guide section provided in the lower part of the housing body and the rod section of the actuating piston, thereby preventing wear, seizure, etc. on the inner and outer circumferential surfaces of both. Occurrence can be prevented.

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a diaphragm vacuum pump according to a first embodiment of the present invention. In this vacuum pump, the housing main body 10 is located at the upper side of the engine in the vehicle, and is connected to the cylinder head C1.
and a cylinder head cover 02, and a diaphragm piston 20 is installed inside the housing body 10.
is installed. Further, a rocker arm 30 is disposed in a space formed by the lower housing 11, the cylinder head C1, and the cylinder head cover 02 that constitute the housing body 10, and an overhead camshaft 40 of the engine is disposed in the space. one end is extended. One end of this camshaft 40 functions as a pump drive shaft.

The diaphragm piston 20 is a disc-shaped diaphragm 2
1, an operating rod 22, and a receiving member 23 are the main components. The diaphragm 21 has its peripheral edge connected to the lower housing 11 and the upper housing 1 of the housing body 10.
2, and a decompression chamber R1, which is a pump chamber, is formed above the pump chamber. The upper surface of this diaphragm 21 has a diaphragm dish 24 with a required thickness.
is fixed to the diaphragm 21, and a disk-shaped spring retainer 25 is fixed to the lower surface of the diaphragm 21.

Diaphragm dish 24 and spring retainer 25
24 and 25 and the flange portion 22 of the actuating rod 22 that passes through the approximate center of the diaphragm 21.
The actuating rod 22 is integrally fixed to the diaphragm 21 by a nut 26 screwed onto the upper end of the actuating rod 22.

The diaphragm piston 20 is supported so as to be slidable in the vertical direction by both guide members 15 and 17 constituting both front guide portions, which will be described later, and is urged upward by the compression spring 13.

In the upper housing 12 of the housing body 10, a suction chamber R2 and a discharge chamber R3 are formed above the decompression chamber R1. The suction chamber R2 communicates intermittently with the decompression chamber R1 via the suction check valve 50a, and communicates with the brake booster through the suction port 12a. Further, the discharge chamber R3 is intermittently communicated with the decompression chamber R1 via the discharge check valve 50b, and communicated with the atmosphere through the discharge port 12b.

As shown in FIGS. 2 and 3, the rocker arm 30 is a press-molded product bent into an abbreviated shape, and includes a bottom plate portion 31 of a predetermined width and a pair of side plate portions 32 rising from both side edges of the bottom plate portion 31.
It is composed of.

Further, the bottom of the rocker arm 30 is formed in an oil sump 33, and the upright part thereof is formed in a bridge 34 leading to the oil sump 33, and the bottom plate 31 in the upright part has an opening 3.
5 is provided. The rocker arm 30 has an intermediate base where the lower housing 11 is attached to the arm portion 1.
An eccentric cam 4 for driving a pump is pivotally supported by a support shaft 14 on the support shaft 1a so as to be swingable in the vertical direction, and the upper end back surface 30a of the eccentric cam 4 is integrally provided with the shaft portion 41 of the camshaft 40.
It abuts the outer periphery of 2 from diagonally above. Further, the lower end fork portion 30b of the locker 7-m 30 is loosely inserted into the outer periphery of the bottom and bottom portions 22a of the operating rod 22, and is received by a receiving member 23, which will be described later.

One end of the camshaft 40 functions as a pump drive shaft, and the shaft portion 41 is concentrically drilled with oil and water 43, and the eccentric cam 42 has a hole extending in the radial direction from the outer periphery of the oil and water 43. An outflow hole 44 is provided therethrough. This outflow hole 44 faces the opening 35 of the rocker arm 30 when the camshaft 40 rotates, and
3 is spouted out by the centrifugal force generated when the camshaft 40 rotates.

Therefore, in the vacuum pump, a cylindrical portion 11C extending in the vertical direction is formed approximately at the center of the partition portion 11b of the lower housing 11, and an annular recess lid opening upward is formed on the outer periphery of the cylindrical portion 11C. ing. In the cylindrical portion 11C of the lower housing 11, its inner hole is connected to the upper large diameter portion 1.
1C1 and a lower small diameter portion 11C2 are formed into a stepped inner hole, and a guide member 15 is removably fitted into the upper large diameter portion 11C1. This guide member 15 consists of a ring-shaped bushing case 1.5a and a bushing 15b press-fitted into the inner hole thereof, and a cylindrical spring retainer 16 fitted on the outer periphery of the cylindrical part 11c, and the spring retainer It is elastically fixed within the upper large diameter portion 11C1 of the cylindrical portion 11c by the action of the compression spring 13 interposed between the cylindrical portions 11c and 11c.

The guide member 15 constitutes a rod guide portion that supports the upper part of the actuating rod 22 of the diaphragm piston 20. Note that the wall portion 11b of the lower housing 11 has
A through hole lie is formed to communicate the upper and lower compartments.

On the other hand, in the bottom wall part 11f of the lower housing 11, there is a stepped hole 11 with a bottom coaxially with the cylindrical part 11c provided in the drawing wall part 11b.
g is formed. The hole 11g is located in the upper large diameter portion 1.
1g1 and a lower small diameter portion 11g2, and a guide member 17 is press-fitted into the upper large diameter portion 11g1.

The guide member 17 is composed of a ring-shaped bushing case 17a and a bushing 17b press-fitted into the inner hole thereof, and constitutes an opening/seven door guide portion that supports the operating port of the diaphragm piston 20 and the lower part of the door 22. Further, the bottom wall portion 11f of the lower housing 11 is formed with an oil hole 11h (communication hole) that extends diagonally downward from the bottom surface and opens at the side of the lower small diameter portion 11g2 of the stepped hole 11g. This oil hole 11
h is for introducing oil ejected toward the bottom from the outflow hole 44 of the eccentric cam 42 into the lower small diameter portion 11g2 of the stepped hole 11g, and discharging the oil in the lower small diameter portion 11g2. The inside of 11g2 is configured as an oil sump.

The actuating rod 22 constituting the diaphragm piston 20 consists of a rod portion 22a of a predetermined length and a flange portion 22b integrally provided above the rod portion 22a.The large diameter portion of the rod portion 22a is a guide. It is formed in a size that allows it to slide in the axial direction with respect to the bushing 15b of the member 15. A receiving member 23 is rotatably fitted onto the outer periphery of the lower 6111 portion of the rod portion 22a. This receiving member 23 consists of a cylindrical portion 23a and an annular receiving portion 23b integrally formed at the upper end thereof, and is fitted onto the outer periphery of the rod portion 22a and attached to the lower end caulking portion 22c of the rod portion 22a. It is prevented from being removed. In addition, the cylindrical portion 23a of the receiving member 23
The outer diameter of the receiving portion 23b of the receiving member 23 is formed to a size that allows the guy to slide in the axial direction and rotate in the circumferential direction relative to the bushing 17b of the member 17. is the cylindrical portion 11 (
It is formed to have a smaller diameter than the inner diameter of the lower small diameter portion 11c2. The operating rod 22 has a guide member whose upper part is directly slidably supported in the axial direction by the bush 15b of the guide member 15 constituting the upper long guide part, and whose lower part constitutes the lower long guide part. 17 bushes 17b via receiving members 23 so as to be slidable in the axial direction. Further, the actuating rod 22 is urged upward together with the diaphragm 21 and the diaphragm dish 24 by the action of a compression spring 130 interposed between both spring retainers 16 and 25. As a result, in the receiving member 23, the lower end fork portion 3 of the rocker arm 30 is inserted into the receiving portion 23b of the receiving member 23.
0b is elastically received, and the upper end back surface 30a of the rocker arm 30 is brought into contact with the outer periphery of the eccentric cam 42.

Both check valves 50a and 50b have the same structure and are assembled in different directions at the opening ends of the suction chamber R2 and the discharge chamber R3. Both check valves 50a and 50b, as illustrated in the suction check valve 50a, include a stepped cylindrical valve case 51 having a large diameter gH1 medium diameter portion and a small diameter portion;
An annular valve seat 52 fixed within the large diameter portion of the valve case 51, a disc-shaped valve body 53 disposed within the medium diameter portion of the valve case 51, and a valve body 53 interposed within the medium diameter portion and the small diameter portion of the valve case 51. and a compression spring 54 that urges the valve body 53 toward the valve seat 52.

In both check valves 50a and 50b, the suction check valve 50a is assembled to the open end of the suction chamber R2 with its top facing downward, and the discharge check valve 50b is assembled to the open end of the suction chamber R2.
It is assembled into the open end of the holder with the top facing upward.

The inner hole at the open end of the suction chamber R2 extends from the open end to the large diameter section 1.
2C1, a medium diameter portion 12C2, and a small diameter portion 12C, 3, and the small diameter portion 12C3 is formed to have a larger diameter than the inner hole of the suction chamber R2.

At this opening end, the valve case 51 of the suction check valve 50a is fitted and positioned in the small diameter part 12C3, and the valve case 51 is fitted in the medium diameter part 12C2.
An O-ring 55 is interposed on the outer periphery of the O-ring 55, and a stepped cylindrical retainer 56 is fitted into the medium diameter portion 12C2 and the large diameter portion 12C1 from the open end side, and this retainer 56 is caulked at the opening edge. has been done. Thereby, the suction check valve 50a is assembled to the open end of the suction chamber R2.

On the other hand, the inner hole at the open end of the discharge chamber R3 is connected from the open end side to the large diameter portion 12d1. A medium diameter portion 12d2 and a small diameter portion 12d3 are formed, and the small diameter portion 12d3 is formed to have a larger diameter than the inner hole of the discharge chamber R3. At this opening end, the valve case 51 of the discharge check valve 50b is fitted into the small diameter part 12d3 for positioning, and the middle diameter part 1
An O-ring 57 is interposed around the outer periphery of the valve case 51 at 2d2, and an annular retainer 58 is fitted to the large diameter portion 12dl, and the retainer 58 is caulked at the opening edge. As a result, the discharge check valve 50b is assembled to the open end of the discharge chamber R3 in a direction different from that of the suction check valve 50a.

Next, the operation of the diaphragm vacuum pump configured as described above will be explained. In this vacuum pump, the camshaft 40 is rotated in the direction of the arrow in FIG. 2 by the drive of the engine, and the rocker arm 30 is repeatedly oscillated in the vertical direction by the action of the eccentric cam 42. As a result, the diaphragm piston 20 is repeatedly moved up and down by the upward biasing action of the compression spring 13 and the downward pushing action of the rocker arm 30. When the diaphragm screws 1 to 20 move upward, the valve body 53 of the suction check valve 50a is seated on the valve seat 52, and the valve body 53 of the discharge check valve 50b is separated from the valve seat 52, so that the decompression chamber The air in R1 passes through the discharge chamber R3 and is discharged to the atmosphere from the discharge bows 1 to 12b. Further, when the diaphragm piston 2o moves downward, negative pressure is generated in the pressure reducing chamber R1, and the valve body 53 of the discharge check valve 50b is seated on the valve seat 52, and the valve body 53 of the suction check valve 50a is pressed against the valve seat 52. Separated from the seat 52, the negative pressure in the decompression chamber R1 passes through the suction chamber R2 and is applied to a brake booster (not shown) from the suction boat 12a.

During this time, in the vacuum pump, oil is supplied to the oil/water 43 of the camshaft 40 by an oil pump (not shown) driven by the engine. A part of this oil is ejected to the outside from the outflow hole 44 due to the centrifugal force generated by the rotation of the camshaft 40, passes through the opening 35 of the rocker arm 30, flows down the bridge section 34, and accumulates in the oil sump section 33. At the same time, the oil flows down from the bottom of the lower housing 11 through the oil hole 11h to the lower small diameter portion IIg of the stepped hole 11g.
It accumulates at 2. The oil accumulated in the oil reservoir 33 of the rocker arm 30 is removed from the lower surface of the guide member 15 and the lower housing 11 by the jumping action when the rocker arm 3o swings and the suction action produced when the diaphragm piston 20 moves upward.
The oil is supplied to the upper surface of the kite member 15 through the through hole lie, and lubricates the sliding portion between the kite member 15 and the operating rod 22.

Further, the oil accumulated in the stepped hole 11g of the lower housing 11 gets caught in the splashing action of the vertical movement of the actuating rod 22 and is supplied to the lower surface of the kite member 17, thereby preventing the sliding portion between the guide member 17 and the actuating rod 22. /II slide. Incidentally, the oil spouted into the inside of the housing body 10 finally flows back to the oil pan from an outflow hole provided at the bottom of the cylinder head C1.

By the way, in this vacuum pump, the actuating rod 22 constituting the diaphragm piston 20 is slidably supported in the axial direction by a pair of upper and lower front guide portions formed by both guide portions +, 4' 15, and 17. There is. Therefore, the movement direction of the actuating rod 22 is regulated in the axial direction by both guide members 15, 17, and the diaphragm 22
1 will not be deformed unevenly, and the diaphragm dish 24 will not be tilted. Therefore, a decrease in the durability of the diaphragm 21 and a decrease in pump efficiency can be reliably prevented. In addition, in this vacuum pump, the horizontal force applied from the rocker arm 30 to the actuating rod 22 is transferred to both guide members 15.
7, the outer periphery of the actuating rod 22, the inner periphery of the bush 15b, and the cylindrical portion 23a of the receiving member 23.
It is possible to reduce wear and seizure occurring between the outer circumference and the inner circumference of the bushing 17b. Furthermore, in the vacuum pump, since the lower end fork portion 30b of the rocker arm 30 is merely received by the receiving portion 23b of the receiving member 23, the swing receiving portion 23b of the rocker arm 30 This causes the lower end fork portion 30b to slip. Therefore, the horizontal force applied from the rocker arm 30 to the actuating rod 22 is reduced, making it possible to further reduce wear and seizure occurring in the above-mentioned parts.

In addition, in the vacuum pump, the inner hole of the cylindrical portion 11C in the lower housing 11 is connected to the upper large diameter portion 11C1.
The guide member 15 is removably fitted into the upper large diameter portion 11C1, and the outer diameter of the receiving portion 23b of the receiving member 23 is shaped like a cylinder. It is formed to have a smaller diameter than the lower small diameter portion 11C2 in the portion 11c. For this reason, the diaphragm piston 20
can be easily assembled into and removed from the lower housing 11 from the upper end opening side of the lower housing 11. In addition, in the vacuum pump,
When assembling both check valves 50a and 50b, the valve case 51 is attached to the small diameter portion 12c3 of the suction chamber R2 or the discharge chamber R3,
12d3, and each medium diameter portion 1
2 c 2° O on the outer periphery of the valve case 51 at 12d2
Rings 55 and 57 are interposed, and each large diameter portion 12C1
The retainers 56 and 58 are fitted onto the 12dl and caulked together. Therefore, due to such assembling means, each check valve 5Qa, 50b is pressed against the valve seat 52 due to an excessively excessive pressing force from each retainer 56, 58.
Deterioration of sealing performance due to distortion of the O-ring 55, 57, deterioration of sealing performance due to wear and damage of the O-ring 55, 57, etc. are prevented.

Therefore, in this embodiment, especially the lower housing 1
A bottomed stepped hole 11g is provided in the bottom wall portion 11f of 1, and an oil hole 11h is provided in the lower small diameter portion 11 of the stepped hole 11g.
g2 is formed in the oil sump. Therefore, the oil in the oil reservoir is supplied between the inner periphery of the bush 17b of the guide member 17 and the outer periphery of the receiving member 23 by the splash action caused by the vertical movement of the operating rod 22. Therefore, compared to the upper guide member 15 side, the guide member 17 and the receiving member 23 have a higher burden rate for the horizontal force and are more susceptible to wear and seizure.
As a result, wear and seizure between the inner periphery of the bushing 17b of the guide member 17 and the outer periphery of the receiving member 23 can be effectively prevented. In addition, when the operating rod 22 moves downward, the oil sump (lower small diameter portion 11
g2) can be allowed to flow out through the oil hole 11h, thereby preventing sludge from accumulating at the bottom of the oil reservoir.

FIGS. 4 and 5 show two modifications to this embodiment. In the modification shown in FIG. 4, a portion of the rocker arm 30A that is close to the lower end fork portion 30b of the bottom plate a++31 is bent upward, and the lower surface of the portion is formed at the opening of the oil hole 11h and the receiving member 23. It is formed in a recess 30c facing a part of the receiving portion 23b. Therefore, part of the oil flowing out through the oil hole 11h when the operating rod 22 moves downward can be reflected toward the receiving part 23b by the recess 3°C and supplied to the receiving part 23b. can. Therefore, it is possible to sufficiently lubricate the space between the receiving portion 23b and the lower end fork portion 30b of the rocker arm 30A, which slide into contact with each other under surface pressure.

Further, in the modification shown in FIG. 5, an opening 36 is formed in the bottom plate portion 31 of the rocker arm 30B in the axial direction of the oil hole 11h.

Therefore, part of the oil accumulated in the oil sump 33 of the rocker arm 30B is guided to the oil hole 11h through the opening 36 and accumulates in the oil sump (lower small diameter portion 11g2), and also under the operating rod 22. A portion of the oil flowing out through the oil hole 11h during operation is supplied to the pivot portion of the rocker arm 30B through the opening 36. Therefore, the shaft portion of the rocker arm 30B can be sufficiently lubricated.

Note that the other configurations and operations in these second modified examples are the same as those in the first embodiment, so other configuration diagrams and detailed explanations thereof will be omitted.

FIG. 6 shows a piston-type vacuum pump according to a second embodiment of the present invention. In this vacuum pump, a housing main body 100 is a lower housing 1.
10 and an upper housing 120, a cylinder liner 130 is fitted into the upper cylindrical part of the lower housing 110, and this part is formed into a cylinder part. The main components of the actuating piston 200 include a disk-shaped piston 210 and an actuating rod 220. The actuating rod 220 includes a rod portion 220a of a predetermined length, and a flan +i+ 220 provided integrally with the rod portion 220a at the upper part thereof.
b, and a receiving part 220c provided integrally with the lower part of the o7 part 220a. This operating rod 220 has its upper end connected to the piston 210.
A Nand 2 screwed into the upper end of the
30 is attached to the piston 210. The operating screw 1-200 is assembled in the cylinder liner 130 of the housing body 100 in an airtight manner and slidable in the axial direction, and is attached to the guide member 140 at the lower end of the operating rod 220 in the axial direction. It is slidably supported. Further, the operating piston 220 is urged upward by a compression spring 240 interposed between the lower surface of the piston 210 and the stepped hole 110a of the lower housing 110, and the receiving portion 220c of the operating piston 220 is biased upwardly by the lower end of the rocker arm 300. The portion 300b is elastically received, and the upper end back surface 300a is brought into contact with an eccentric cam (not shown).

As a result, in the vacuum pump, a decompression chamber R1, which is a pump chamber, is formed above the piston 210 of the working piston 200. This decompression chamber R1 is connected to the suction chamber R2 and the atmosphere through a suction check valve 500a assembled to the open end of the suction chamber R2 provided in the upper housing 120 and a discharge check valve 500b assembled to the piston 210. It is designed to be selectively communicated with. Therefore, in this vacuum pump, when the engine is driven, the rocker arm 300 is repeatedly oscillated and the working piston 200 reciprocates. Therefore, similarly to the diaphragm vacuum pump in the first embodiment, the negative pressure generated in the decompression chamber R1 passes through the suction chamber R2 and is applied to a brake booster (not shown) from the suction port 120a.

In this vacuum pump as well, the bottomed stepped hole 110c is formed in the bottom wall portion 110b of the lower housing 110.
is formed. This stepped hole 110C consists of an upper large diameter part 110cl and a lower small diameter part 110c2,
A guide member 140 is press-fitted into the upper large diameter portion 110c1. In addition, the bottom wall portion 110 of the lower housing 110
b has a stepped hole 110c extending obliquely downward from the bottom surface thereof.
Oil hole 11Qd opened on the side of the lower small diameter portion 110c2
is formed, and the lower small diameter portion 110C2 serves as an oil reservoir. Therefore, the oil accumulated in this oil reservoir is splashed by the vertical movement of the operating rod 220, and the inner circumference of the bushing 140b of the kite member 140 and the operating rod 2.
It is supplied between the outer peripheries of 20 lot portions 220a. Therefore, hot water can be properly applied between the inner and outer circumferences of both, and wear and tear occurring between the inner and outer surfaces 12 and 1 can be effectively prevented.

In addition, in each Example, the present invention is described as C;1-
Although an example has been shown in which the present invention is applied to a neem pump, the present invention is applicable to a piston part of a diaphragm type fuel pump, a bison type fuel pump, etc., by assembling the working piston inside the housing body so as to be able to reciprocate in the axial direction. A pump chamber is formed on one side, and the rotary part of the actuating piston is connected to the swinging end of a first car arm that swings by the rotation of the pump drive shaft, and the working piston is connected to the swinging end of the first car arm that swings by the rotation of the pump drive shaft. Examples of various types of fluid pumps that generate positive ratio or negative pressure in the njj pump chamber by reciprocating in the axial direction

[Brief explanation of the drawing]

FIG. 1 is a front view of a vacuum pump according to an example of the present invention, FIG. 2 is a vertical side view of the same vacuum pump, and FIG. 3 is a bottom view of a rocker arm in the same vacuum pump.
FIG. 4 is a partially omitted longitudinal side view showing a first modification of the same vacuum pump, FIG. 5 is a partially omitted longitudinal side view showing a second modification of the same vacuum pump, and FIG. 6 is a partially omitted longitudinal side view showing a second modification of the same vacuum pump. FIG. 7 is a longitudinal side view of a vacuum pump according to a second embodiment. Explanation of symbols 10...Housing body, 11...Lower housing, l1g...Stepped hole, 11g1...Upper large diameter part, 1
1g2...Lower small diameter part (oil sump), 11h...oil hole, F...guide member, 20...diaphragm piston, 21...diaphragm, 22...operating rod, 30. 30A. 30B... Rocker arm, 30C... Recess, 36
...Opening, 40...Camshaft, 100...
Housing body, 110c...Stepped hole, 110d...
・Oil hole, 200... Operating piston, 210...
Piston, 220... Operating Rondo, 300...
Rocker arm, R1...decompression chamber. Applicant Toyota Motor Corporation (and 1 other person) Agent
Patent Attorney Teru Hase - Figure 4 Figure 5

Claims (1)

[Claims] The actuating piston is assembled inside the housing body so as to be able to reciprocate in the axial direction, and a pump chamber is formed on one side of the piston portion of the actuating piston, and the rod portion of the actuating piston is oscillated by rotation of the pump drive shaft. A fluid pump that is connected to a swinging end of a rocker arm, and that the operating piston is reciprocated in the axial direction by the swinging motion of the rocker arm to generate positive or negative pressure in the pump chamber. A lower part of the rod part of the actuating piston is slidably supported in the axial direction by a rod guide part provided in a lower part of the housing body, and a rod guide part of the actuating piston is provided at the bottom of the housing body. b, a recess whose lower end faces forward and backward, and a communication hole that extends downward from the bottom surface of the housing body and communicates with the recess, and the recess is formed in an oil sump part. pump.