JP2011038423A - Plunger pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plunger pump for improving assemblability. <P>SOLUTION: This plunger pump includes a plunger 1 arranged in an inner hole HS2 formed in a housing HS, an eccentric cam OC arranged in a cam storage hole HS3 formed in the housing and reciprocating the plunger 1 in the inner hole HS2 by abutting on one end side of the plunger 1, a valve element 3d abutting on a valve seat 1d arranged on the other end side of the plunger 1, and a retainer part 3 for storing the valve element 3d inside and installed on the other end side of the plunger 1. The retainer part 3 has an opening part 3n for storing the valve element 3d inside, a spring holding part 3a arranged in a position opposed to the opening part 3n, and a valve element holding part 3h capable of holding the valve element 3d in a state of being stored inside the retainer part 3, and is installed in the plunger 1 in a sub-assembly state of storing the valve element 3d inside. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a plunger pump.

  The conventional plunger pump forms a valve seat at the opening end desired in the pressure chamber of the axial hole formed in the plunger, this valve seat, a ball valve body for opening and closing the valve seat, and urging the valve body in the closing direction And a retainer member that holds the spring constitutes a suction valve (see, for example, Patent Document 1).

JP 2006-170080 A

However, in the above prior art, there is a problem that the assembling property is poor because the three parts of the retainer member, the valve body, and the spring are separately attached.
The objective of this invention is providing the plunger pump which improved the assembly | attachment property.

  In this invention, the holding part holding the valve body accommodated in the inside of a retainer member is provided, and a retainer member is attached to a plunger in the temporary assembly state which accommodated the valve body in the inside.

  Therefore, according to the present invention, the assembling property is improved.

1 is a longitudinal sectional view of a plunger pump P of Example 1. FIG. 3 is a longitudinal sectional view showing a state in which a valve body 3d and a coil spring 3c are sub-assembled to the retainer R of Embodiment 1. FIG. FIG. 3 is a bottom view of the retainer R according to the first embodiment. 3 is a perspective view of a retainer R according to Embodiment 1. FIG. FIG. 3 is an enlarged view of main parts of FIG. 2. FIG. 3 is a diagram illustrating a method for manufacturing the retainer R according to the first embodiment. 6 is a longitudinal sectional view of a retainer R in Embodiment 2. FIG. It is a principal part enlarged view of FIG. 6 is a longitudinal sectional view of a retainer R in Example 3. FIG. 6 is a bottom view of a retainer R of Example 3. FIG. It is a longitudinal cross-sectional view of the retainer R of the other Example 1.

  EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the plunger pump of this invention is demonstrated based on the Example shown on drawing.

First, the configuration will be described.
FIG. 1 is a longitudinal sectional view of the plunger pump P of the first embodiment. The plunger pump P of the first embodiment is applied to a pump that controls the brake fluid pressure of the vehicle.
The plunger pump P is accommodated in an inner hole (cylinder hole) HS2 formed from a side surface HS1 of the housing HS formed of, for example, an aluminum block. In the inner hole HS2, an inlet 10 for sucking in brake fluid and an outlet 11 for discharging pressurized brake fluid are opened. In the inner hole HS2, the plunger 1 reciprocated by the eccentric cam OC, the suction valve 4 provided at the tip of the plunger 1, the discharge valve 6 fixed to the housing HS, and the inner hole HS2 are connected to the outside of the housing. And a plug member 7 sealed between the two.
The plunger 1 has a main shaft portion 110 having substantially the same diameter as the inner hole HS2 and a sub shaft portion 111 having a smaller diameter than the main shaft portion 110 and having the suction valve 4 formed at the tip. On the outer periphery of the main shaft portion 110, a low-pressure seal member 1c that seals between the cam housing hole (cam chamber) HS3 and the suction port 10 is provided. Since the cam housing hole HS3 is basically formed as a dry chamber, the brake fluid sucked from the suction port 10 is prevented from flowing out. The cam housing hole HS3 is opened to the atmosphere, and the brake fluid flowing through the suction port 10 is almost at the atmospheric release pressure, so that there is no significant pressure difference. A through hole 1a is formed at a position in the radial direction of the main shaft portion 110 and coincident with the suction port 10. The through hole 1a has a smaller diameter than the suction port 10, and is always in communication with the suction port 10 when the plunger 1 reciprocates by the eccentric cam OC. In the axial direction of the plunger 1, there is formed an axial hole 1b penetrating through the auxiliary shaft portion 111 and communicating the suction valve 4 and the through hole 1a. A valve seat (valve seat portion) 1d is formed at the tip of the auxiliary shaft portion 111 and at the opening of the axial hole 1b.

A retainer R is attached to the countershaft portion 111. In this retainer R, the high-pressure seal portion 2 and the retainer portion (retainer member) 3 are integrally formed of synthetic resin. The high-pressure seal portion 2 is a seal member and is press-fitted and fixed to the outer periphery of the auxiliary shaft portion 111.
The high-pressure seal portion 2 is an annular member, and includes a bottom surface portion 2f that contacts the step portion 1f of the main shaft portion 110 and the sub shaft portion 111 of the plunger 1, an outer shape portion 2e that does not contact the inner hole HS2, and an outer shape portion 2e. It has a lip 2a urged by the inner hole HS2 and a lip groove 2c formed inside the lip 2a. When a high pressure is applied to the pump chamber 20, the high pressure is guided to the lip groove 2c to expand the diameter of the lip 2a and form a seal surface with the inner hole HS2.
The retainer portion 3 includes an opening 3n, an inner diameter portion 3i that contacts the large diameter portion 111a of the auxiliary shaft portion 111, a valve body holding portion (holding portion) 3h that contacts the small diameter portion 111b of the auxiliary shaft portion 111, and a spring. 5f, the enlarged diameter portion 3f serving as a pedestal, the cylindrical portion 3b extending cylindrically from the enlarged diameter portion 3f, and closing the cylindrical portion 3b and urging the ball-shaped valve body 3d against the valve seat 1d A spring holding part (bottom part) 3a for holding the coil spring 3c to be formed, a flow hole 3e formed in the center of the spring holding part 3a for introducing brake fluid into the pump chamber 20 during suction operation, and a cylindrical part 3b It has three slit portions 3g (see FIG. 4) for introducing brake fluid into the pump chamber 20 during the suction operation. The inner diameter part 3i is press-fitted into the large diameter part 111a of the auxiliary shaft part 111 to form a seal surface over the entire circumference between the inner diameter part 3i and the large diameter part 111a. The valve seat 1d, the valve body 3d, the coil spring 3c, and the retainer portion 3 constitute the suction valve 4.

2 is a longitudinal sectional view showing a state where the valve body 3d and the coil spring 3c are sub-assembled (temporarily assembled) to the retainer R of the first embodiment, FIG. 3 is a bottom view of the retainer R of the first embodiment, and FIG. 1 is a perspective view of the retainer R of FIG. 1, and FIG. 5 is an enlarged view of a main part of FIG. As shown in FIG. 2, the retainer R is attached to the plunger 1 integrally with the valve body 3d and the coil spring 3c after being put into a sub-assembly state in which the valve body 3d and the coil spring 3c are accommodated. As shown in FIG. 1, the valve body 3d is positioned by the valve seat 1d in a state where the retainer R is attached to the plunger 1, but before the retainer R is attached to the plunger 1, as shown in FIG. In the sub-assembly state, positioning is performed by the valve body holding portion 3h.
Three valve body holding portions 3h are provided at equal intervals (120 ° intervals) in the circumferential direction of the retainer portion 3. As shown in FIG. 5, the valve body holding portion 3h includes a holding portion 3j having an outer diameter smaller than that of the valve body 3d and tapered portions 3k and 3m tapered in the axial direction of the retainer portion 3. When the valve body 3d is in the sub-assembled state, the valve body 3d engages with the tapered portion 3m and is held in the retainer portion 3. The inner diameter of the holding portion 3j, that is, the distance from the center of the retainer R to the holding portion 3j is set smaller than the outer diameter of the valve body 3d. Further, the height H of the holding portion 3j from the inner diameter of the cylindrical portion 3b is set to be, for example, 7% or less with respect to the inner diameter of the holding portion 3j. Furthermore, the maximum diameter of the coil spring 3c is set smaller than the inner diameter of the holding portion 3j.

  At the right end of the pump chamber 20 in FIG. 1, a valve seat member 60 and a filter 61 attached to the valve seat member 60 are provided. The filter 61 serves as a base for the spring 5, and a plurality of through holes are formed, thereby suppressing the outflow of dust and applying an orifice effect to reduce the pulse pressure. The valve seat member 60 is formed with an axial hole 6a and a valve seat 6b. The valve seat member 60 is provided with a plug member 7, and a ball-shaped valve body 6c is urged against the valve seat 6b by a spring 6d attached to the plug member 7, thereby constituting the discharge valve 6. . A discharge chamber 7 a is formed between the valve seat member 60 and the plug member 7. Further, an axial gap 7b is formed in a part between the valve seat member 60 and the plug member 7, and is connected to a circumferential annular gap 7c communicating with the axial gap 7b. A plurality of radial grooves 7d formed radially on the side surface of the valve seat member 60 of the plug member 7 are connected to the annular gap 7c. The valve seat member 60 is sandwiched between the housing HS when the plug member 7 is fixed by caulking.

Next, the operation will be described.
Since the retainer R of Example 1 is made of a synthetic resin, it has an advantage that it can be easily molded using injection molding. FIG. 6 is a diagram illustrating a method for manufacturing the retainer R according to the first embodiment. First, clamping is performed by two fixed molds 8a and 8b and one movable mold 8c, and molten resin is injected from a resin injection gate 8e into a cavity 8d formed inside the molds 8a to 8c, and is cooled and solidified. (FIG. 6 (a)). Subsequently, the movable mold 8c is separated and the mold is opened (FIG. 6 (b)), the ejector pipe 8f is advanced, and the molded product body (retainer R) is discharged (FIG. 6 (c)).
Here, since the high-pressure seal part 2 and the retainer part 3 are integrally formed, the number of parts and the number of molds can be reduced compared to the conventional product in which the high-pressure seal and the retainer member are separate from each other. Cost can be reduced. Further, the high pressure seal portion 2 and the retainer portion 3 can be attached to the plunger 1 only by press-fitting and fixing the retainer R to the plunger 1, so that the assembling property can be improved. Further, when the retainer R is discharged from the mold using the injector pipe 8f, the height of the holding portion 3j of the retainer R is set as described above, so that the discharge can be easily performed.

Next, a procedure for sub-assembling the valve body 3d and the coil spring 3c to the retainer R and attaching them to the plunger 1 will be described. First, the coil spring 3c is inserted into the retainer portion 3. Here, since the maximum diameter of the coil spring 3c is set smaller than the inner diameter of the valve body holding portion 3h (holding portion 3j), the coil spring 3c can be smoothly retained without interfering with the valve body holding portion 3h. Can be inserted inside part 3.
Subsequently, the valve body 3d is inserted into the retainer portion 3. Although the inner diameter of the holding part 3j is smaller than the outer diameter of the valve body 3d, the retainer part 3 is made of synthetic resin, and the valve body holding part 3h is intermittently arranged in the circumferential direction of the retainer part 3. Therefore, by pushing the valve body 3d, the valve body 3d can be easily inserted into the retainer section 3 while expanding the diameter of the retainer section 3. Here, a taper portion 3k tapered in the axial direction of the retainer portion 3 is set in the valve body holding portion 3h, and the height H from the inner diameter of the cylindrical portion 3b of the holding portion 3j is set to the inner diameter of the holding portion 3j. On the other hand, since it is set to be 7% or less, it can be easily pushed into the retainer portion 3 without damaging the valve body 3d.

Next, the retainer R in which the valve body 3d and the coil spring 3c are sub-assembled as described above is press-fitted and fixed to the auxiliary shaft portion 111 of the plunger 1. Here, the valve body 3d sub-assembled in the retainer R is accommodated in the retainer portion 3 in a state of being sandwiched between the coil spring 3c and the valve body holding portion 3h. That is, since the valve body 3d is positioned by the coil spring 3c and the valve body holding portion 3h, the valve body 3d is not dropped from the retainer R until the retainer R is attached to the plunger 1, and the sub-assembly state Can be maintained.
When the retainer R is press-fitted into the auxiliary shaft portion 111 until the bottom surface portion 2f comes into contact with the step portion 1f of the main shaft portion 110 and the auxiliary shaft portion 111 of the plunger 1, the valve body 3d is in contact with the valve seat 1d in FIG. It is pressed toward the middle right side, that is, the spring holding portion 3a side, and is separated from the valve body holding portion 3h, and is sandwiched between the coil and the valve seat 1d. Thereby, the function of the suction valve 4 is ensured. In other words, the retainer R does not have the valve seat function of the intake valve 4, and the plunger 1 has the valve seat function, so a metal material is used for the valve seat 1d, and the conventional durability can be ensured. It becomes possible. In addition, when selecting a material for the high-pressure seal portion 2, it is not necessary to consider the durability required for the valve seat 1d, so the degree of freedom in material selection can be increased.

Next, effects of the plunger pump P of Example 1 are listed.
(1) Plunger 1 disposed in an inner hole HS2 formed in the housing HS, and a plunger 1 disposed in a cam receiving hole HS3 formed in the housing and in contact with one end side of the plunger 1 to place the plunger 1 in the inner hole HS2 An eccentric cam OC that reciprocates inside, a valve body 3d that comes into contact with a valve seat 1d provided on the other end of the plunger 1, and a retainer portion that houses the valve body 3d and is attached to the other end of the plunger 1 The retainer part 3 includes an opening 3n for accommodating the valve body 3d therein, a spring holding part 3a provided at a position facing the opening 3n, and the valve body 3d as the retainer part 3 And a valve body holding portion 3h that can be held in a state of being housed inside, and attached to the plunger 1 in a sub-assembly state in which the valve body 3d is housed therein.
As a result, the retainer portion 3 can be integrally attached to the plunger 1 in a sub-assembly state in which the valve body 3d and the coil spring 3c are accommodated, so that the ease of assembly with respect to the conventional product can be improved.
(2) The valve body holding part 3h protrudes inward of the retainer part 3, and the valve body 3d is engaged with and held by the valve body holding part 3h in the sub-assembled state. Part 3h can be formed.
(3) A spring (coil spring 3c) is provided between the spring holding portion 3a and the valve body 3d so as to urge the valve body 3d toward the valve seat 1d. The valve body 3d is a spring when in the sub-assembled state. And the valve body holding portion 3h.
As a result, the valve body 3d can be stably accommodated in the retainer portion 3, and the sub-assembly state can be maintained without the valve body 3d falling off the retainer portion 3 until the retainer portion 3 is attached to the plunger 1. . Therefore, it is possible to improve the assembling property of the retainer R.

(4) Since the spring is a coil spring 3c having a maximum diameter smaller than the inner diameter of the valve body holding portion 3h, when the coil spring 3c is accommodated in the retainer portion 3, interference with the valve body holding portion 3h can be avoided. The assembling property of the coil spring 3c can be improved.
(5) The plunger 1 disposed in the inner hole HS2 formed in the housing HS, the valve body 3d contacting the valve seat 1d provided on the other end side of the plunger 1, and the valve body 3d accommodated therein And a valve body 3d is positioned by the valve seat 1d when the retainer portion 3 is attached to the other end of the plunger 1, and is removed from the other end of the plunger 1. In the assembled state, positioning is performed by a valve body holding portion 3h formed in the retainer portion 3.
As a result, the retainer part 3 can be integrally attached to the plunger 1 in the sub-assembly state in which the valve body 3d and the coil spring 3c are accommodated, so that the number of assembling steps can be reduced compared to the conventional product and the assembling property can be improved. be able to. In addition, since the retainer R does not have the valve seat function of the suction valve 4, there is no need to consider the durability required for the valve seat 1d when selecting the material for the high pressure seal part 2, and the degree of freedom in material selection is reduced. Can be increased.
(6) Because the retainer R is formed by integrating the retainer part 3 and the high-pressure seal part 2, it is possible to reduce the number of parts and the number of molds compared to the conventional product, thereby reducing the manufacturing cost and improving the assembly. Can be planned.
(7) Since the inner diameter portion 3i of the retainer portion 3 is press-fitted and fixed to the large diameter portion 111a of the countershaft portion 111 of the plunger 1, the seal surface is provided over the entire circumference between the inner diameter portion 3i and the large diameter portion 111a. And the leakage of hydraulic oil from the pump chamber 20 to the suction port 10 can be prevented.

Next, Example 2 will be described with reference to FIGS. FIG. 7 is a longitudinal sectional view of the retainer R in the second embodiment, and FIG. 8 is an enlarged view of a main part of FIG. In addition, about the site | part which is common in Example 1, it represents with the same name and the same code | symbol.
The second embodiment is different from the first embodiment in that the shape of the valve body holding portion 3h of the retainer R is a longitudinal section R shape (arc shape) and the slit portion 3g of the retainer portion 3 is deleted. The inner diameter of the valve body holding portion 3h, that is, the distance from the center of the retainer R to the valve body holding portion 3h is set smaller than the outer diameter of the valve body 3d. Further, the height H from the inner diameter of the tubular portion 3b of the valve body holding portion 3h is set to be, for example, 7% or less with respect to the inner diameter of the valve body holding portion 3h. Further, the maximum diameter of the coil spring 3c is set smaller than the inner diameter of the valve body holding portion 3h.
Also in the second embodiment, the same effect as that of the first embodiment can be obtained.

Next, Example 3 will be described with reference to FIGS. 9 is a longitudinal sectional view of the retainer R in the third embodiment, and FIG. 10 is a bottom view of the retainer R in the third embodiment. In addition, about the site | part which is common in Example 1, it represents with the same name and the same code | symbol.
The third embodiment is different from the first embodiment in that the valve body 3d constituting the suction valve 4 is a flat disk-shaped flat valve. Although not shown, the shape of the valve seat 1d is also changed in accordance with the shape of the valve body 3d.
Five valve body holding portions 3h according to the third embodiment are provided at equal intervals (72 ° intervals) in the circumferential direction of the retainer portion 3. Here, the length of the inner diameter portion 3i excluding the height of the valve body holding portion 3h is A, the interval between the adjacent valve body holding portions 3h, 3h is B, and the thickness of the valve body 3d (the length in the axial direction) ) Is C and the diameter of the valve body 3d is D, the dimensions of each part are set so that both A <D and B <C are satisfied.
As a result, when the valve body 3d is sub-assembled to the retainer R, the valve body 3d, which is a flat valve, becomes vertical (when the axial direction of the valve body 3d is perpendicular to the axis of the retainer 3). However, until the retainer R is attached to the plunger 1, the valve body 3d is not dropped from the retainer R, and the sub-assembled state can be maintained.
Other functions and effects are the same as those in the first embodiment.

(Other examples)
As mentioned above, although the form for implementing this invention was demonstrated based on the Example, the specific structure of this invention is not limited to the structure shown in the Example, and does not deviate from the summary of invention. Any change in the design of the range is included in the present invention. For example, in the embodiment, an example in which the high-pressure seal portion 2 and the retainer portion 3 are made of the same material has been shown, but both materials may be made different as shown in FIG.

The technical ideas other than the invention described in the scope of claims ascertained from the embodiments will be described below.
(a) A plunger pump in which a retainer portion and a high-pressure seal portion are integrally formed.
According to the present invention, the number of parts and the number of dies can be reduced, the manufacturing cost can be reduced, and the assembling property can be improved.
(b) A plunger pump in which the retainer is press-fitted and fixed to the plunger.
According to this invention, leakage of hydraulic oil from the pump chamber to the suction port can be prevented.
(c) The plunger pump, wherein the spring is a coil spring having a maximum diameter smaller than the inner diameter of the holding portion.
According to the present invention, when the coil spring is accommodated in the retainer member, it is possible to avoid interference with the holding portion, and to improve the assembling property of the coil spring.
(d) a plunger disposed in a cylinder hole formed in the housing, a valve body that comes into contact with a valve seat provided on the other end of the plunger, and a cup-shaped retainer member that houses the valve body therein. The valve body is positioned by the valve seat when the retainer member is attached to the other end side of the plunger, and is positioned by a holding portion formed on the retainer member when the retainer member is detached from the other end side of the plunger. Plunger pump characterized by that.
According to this invention, since it can be integrally attached to the plunger in a sub-assembly state in which the valve element is accommodated in the retainer member, the number of assembling steps can be reduced with respect to the conventional product, and the assembling property can be improved.

HS housing
HS2 bore (cylinder bore)
HS3 Cam receiving hole (cam chamber)
OC eccentric cam
1 Plunger
1d Valve seat (valve seat)
3 Retainer (Retainer member)
3a Spring holder (bottom)
3d disc
3h Valve body holding part (holding part)
3n opening

Claims (3)

A plunger disposed in a cylinder hole formed in the housing;
An eccentric cam disposed in a cam chamber formed in the housing and abutting on one end of the plunger to reciprocate the plunger in the cylinder hole;
A valve body in contact with a valve seat provided on the other end of the plunger;
A retainer member that accommodates the valve body therein and is attached to the other end of the plunger;
With
The retainer member has an opening for accommodating the valve body therein, a bottom provided at a position facing the opening, and a retainable member that can be held in a state in which the valve body is accommodated in the retainer member. And a plunger pump that is attached to the plunger in a temporarily assembled state in which the valve body is accommodated therein. The plunger pump according to claim 1, wherein
The holding portion protrudes inward of the retainer member,
The valve pump is engaged with and held by the holding portion in the temporarily assembled state. The plunger pump according to claim 1 or 2,
A spring that is compressed between the bottom and the valve body and biases the valve body toward the valve seat;
The plunger pump according to claim 1, wherein the valve body is sandwiched between the spring and the holding portion in the temporarily assembled state.

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