JP2890843B2 - Radial plunger pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radial plunger type pump and, more particularly, to a control system which generates a high hydraulic pressure and requires a high-pressure liquid such as an antilock brake system or a traction control system of a vehicle. The present invention relates to downsizing of a radial plunger type pump used and reduction of vibration.

[0002]

2. Description of the Related Art Conventionally, various radial plunger pumps have been provided.

For example, a radial plunger type pump shown in FIG. 9 is of a type used for an anti-lock brake system, which reduces costs and is limited in size due to mounting on a vehicle. Cam means 3 provided with two operating plungers 1A and 1B arranged on the drive shaft 2
To alternately operate the stroke.

However, as is apparent from the relationship between the instantaneous discharge amount and the rotation angle of the pump shown in FIGS. 10 and 11, the number of pulsations generated on the drive shaft per rotation is smaller when the number Z of plungers is even. , Z times (period is 2π / Z), whereas when the number Z of plungers is odd, 2Z
It is generally known that the number of times (the period is π / Z). That is, it is desirable that the number of plungers is an odd number in order to suppress vibration and noise due to fluctuations in hydraulic pressure.

[0005] Therefore, in the case of a radial plunger type pump used particularly for a vehicle such as an automobile, the noise due to the pulsation of the drive shaft is reduced while taking into account the size restrictions and cost reduction. As shown in FIG. 1, there is provided a configuration in which three plungers 5A, 5B, and 5C, which are the minimum number in the case of an odd number, are radially arranged at regular intervals of θ1 = 120 °.

[0006]

However, in the radial plunger type pump described above, three plungers 5A, 5B and 5C each having a predetermined length are connected to one as described above.
Since the plunger housings 6 are arranged at intervals of 20 °, the plunger housing 6 spreads in all directions of 360 ° around the drive shaft 7, and the size of the plunger housing 6 is inevitably increased.

[0007] Further, since the plungers 5A, 5B, and 5C are arranged at 120 ° intervals as described above, a rotational load is applied to the drive shaft 7 that drives the reciprocating operation of the plungers 5A, 5B, and 5C, and solid vibration is likely to occur. The solid vibration generated in the drive shaft 7 passes through various components from the drive shaft 7 and then generates air vibration, that is, noise, through the plunger housing 13.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the conventional radial plunger type pump, and it is possible to reduce the size and the size of the pump while maintaining the vibration and noise caused by the fluctuation of the hydraulic pressure in a low state. The purpose of the present invention is to reduce the vibration and noise generated by the solid vibration of the drive shaft.

[0009]

SUMMARY OF THE INVENTION Accordingly, the present invention comprises three actuating plungers radially disposed around a cam chamber of a plunger housing and driven by a drive shaft protruding into the cam chamber to sequentially perform a stroke operation. A radial plunger type pump, wherein first and second actuation plungers are arranged on a first plane at an angle of 120 ° about an axis of a drive shaft, and are spaced apart from the first plane by a predetermined distance. On a second parallel plane, a third operating plunger whose vertical mapping is at an angle of 60 ° with respect to the axis of the first and second operating plungers and the axis of the drive shaft, respectively, is arranged. A first eccentric cam acting on the distal end portions of the first and second operating plungers is attached, and the first eccentric cam is connected in series with the first eccentric cam,
The present invention provides a radial plunger type pump characterized in that a second eccentric cam acting on the distal end of a third operating plunger is attached with a phase shift of .degree.

[0010]

In the radial plunger type pump according to the present invention, the first and second operating plungers are set on the first plane by 120 degrees.
The third actuation plunger is arranged at an angle of 60 ° and the third projection plunger is arranged on a second plane parallel to the first plane at a predetermined distance from the first plane so that the vertical mapping forms an angle of 60 ° with the first and second actuation plungers. , The size of the plunger housing can be reduced as compared with the case where three operating plungers are arranged at equal intervals of 120 °.

The first and second operating plungers and the third operating plunger arranged as described above are driven by first and second eccentric cams arranged in series with the drive shaft with a phase shift of 180 °, respectively. Therefore, the force acting on the drive shaft during operation is only from one side in the circumferential direction of the drive shaft, so that vibration of the drive shaft can be reduced and noise can be prevented.

[0012]

Next, the present invention will be described in detail based on an embodiment shown in the drawings. The radial plunger pump according to the embodiment of the present invention shown in FIGS. 1 to 6 is arranged radially around the cam chamber 9 in the circumferential direction of the axis L1 of the drive shaft 11 supported by the bearing 10 for the drive shaft. Three operating plungers, ie, the first operating plunger 1
2A, a second operating plunger 12B and a third operating plunger 12C.

The operating plungers 12A, 12B, 12C
Are slidably disposed in a plunger case 14 in a plunger housing 13, respectively.
A spring 17 is inserted between the stop member 4 and the stop member 15 attached to the distal end of the operating plunger 12 to urge the first and second eccentric cams 25 described later.

A first liquid chamber 12a is formed inside the operating plunger 12, and an inflow port 12b communicating with a suction passage (not shown) and a flow communicating with a second liquid chamber 14a in the plunger case 14. An outlet 12c is provided. The outlet 12c has a first ball valve 20 for preventing backflow.

In the plunger case 14, the second liquid chamber 1
4a and a third liquid chamber 14b, a second
A ball valve 21 is provided, and a discharge path is provided in the third liquid chamber 14b.
(Not shown) is provided with a discharge port 14c.

The plunger case 14 and the operating plunger 12 are fixed in the plunger housing 13 by a removable plug member 23.

First and second operating plungers 12A, 12
B is disposed on a first plane P1 perpendicular to the axis L2 of the plunger housing 13. The first operating plunger 12A and the second operating plunger 12B are arranged so as to form an angle of θ2 = 120 ° about the axis L2 of the drive shaft 11.

The third operating plunger 12C is provided on a first plane P on which the first and second plungers 12A and 12B are arranged.
It is arranged on a second plane P2 perpendicular to the axis L2 (that is, parallel to the first plane P1) at a predetermined interval t from 1. The third operating plunger 12C is spatially twisted relative to the first and second operating plungers 12A and 12B, and as shown in FIG.
The same plane perpendicular to the operating plungers 12A, 12B and the axis L2 (for example, the first or second plane P1, P2
When projected to 2), the angles formed by the vertical mapping of the third operating plunger 12C and the first and second operating plungers 12A and 12B are θ3 and θ4 = 60 °, respectively.

In the radial plunger type pump of this embodiment, the operating plungers 12A, 12B and 12C are arranged as described above. The plunger housing 13 can be made smaller in comparison.
That is, conventionally, as shown by the two-dot chain line 12'C in FIG. 5, 36 is provided in the circumferential direction to accommodate the operation plunger 12'C corresponding to the third operation plunger 12C of this embodiment.
Although it was necessary to spread by 0 °, in this embodiment, the first
And the second plungers 12A and 12B are arranged at an interval of θ2 = 120 °, and the third plunger 12C is disposed between the first and second plungers 12A and 12B at the same angle θ.
3, since the arrangement is made so that θ4 = 60 °, the plunger housing 13 may be extended 120 ° in the circumferential direction around the axis L2, and the plunger housing 13 may be disposed at a portion corresponding to the above 12′C ′. Can be smaller.

The first and second operating plungers 12A,
The end 12d of the drive shaft 12B on the axis L1 side of the drive shaft 11 is in contact with the first eccentric cam 25A attached to the drive shaft 11 on the plane P1 via a bearing 26 for the eccentric cam. Second actuation plunger 12
A and 12B are configured to be driven by the first eccentric cam 25A to perform a stroke operation inside the plunger case 14.

On the other hand, the end 12d of the third operating plunger 12C on the side of the axis L1 also has a second eccentric cam mounted on the drive shaft 11 on the plane P2 similarly to the first and second operating plungers 12A and 12B. 25B is in contact with the eccentric cam bearing 26.

In the present embodiment, the first and second eccentric cams 25A and 25B are of an integral structure and are respectively located on the planes P1 and P2 separated by a predetermined distance as described above, as shown in FIG. Have a 180 ° phase shift.

During operation of the radial plunger type pump of this embodiment, when the drive shaft 11 rotates, the first and second eccentric cams 25A and 25B rotate, and the first eccentric cam 2
5A, the first and second actuation plungers 12A, 12B
A stroke movement to suck and discharge a fluid (for example, oil), while the second eccentric cam 25B also causes a stroke movement of the third working plunger 12C. In the present embodiment, the above-described stroke movement occurs sequentially in the order of the first operating plunger 12A, the second operating plunger 12B, and the third operating plunger 12C or in the reverse order.

At this time, as shown in FIG. 8, the drive shaft 11 arranges the first and second actuation plungers 12A and 12B at an interval of θ2 = 120 ° as described above, and the third actuation plunger 12C Between the first and second plungers 12A and 12B and θ3 and θ4 = 60, respectively.
Therefore, the drive shaft 11 receives the force of the actuation plunger 12 from only one side in the circumferential direction, as shown by the arrow F, since they are arranged at intervals of °. Therefore, the drive shaft 1
The force that 1 receives during operation is not a rotational load, but can reduce vibration.

It should be noted that the present invention is not limited to the above embodiment, but can be modified within the technical scope of the present invention. For example, the configuration of the operating plunger, the plunger case, and the like is not limited to those described above, and may be configured by other various types of plungers, plunger cases, and the like.

The first and second eccentric cams do not necessarily have to be integrated, but may be independent eccentric cams.

[0027]

As is apparent from the above description, the radial plunger type pump according to the present invention has the first and second plungers of the three working plungers on the first plane at 120 ° about the axis of the drive shaft. And a third mapping of the third actuation plunger on the second plane parallel to the first plane at a predetermined distance from the first and second planes.
Since they are arranged at an angle of 60 ° with respect to the working shaft, the number of working plungers remains at three, which is preferable for preventing vibration and noise due to pulsation.
The size of the plunger housing can be reduced.

Further, the operating plungers are arranged as described above, and the first eccentric cam for driving the stroke motion of the first and second operating plungers and the second eccentric cam for driving the third operating plunger are 180. ° so as to have a phase shift, at the time of operation, the force applied to the drive shaft from the operating plunger is a load applied only from one side in the circumferential direction, so the drive shaft is less likely to generate solid vibration, It has various advantages such as prevention of generation of vibration and noise.

[Brief description of the drawings]

FIG. 1 is a front view showing a radial plunger type pump according to an embodiment of the present invention.

FIG. 2 is a right side view of FIG.

FIG. 3 is a left side view of FIG. 1;

FIG. 4 is a sectional view taken along line BB of FIG. 2;

FIG. 5 is a sectional view taken along line CC of FIG. 1;

FIG. 6 is a sectional view taken along line DD of FIG. 1;

FIG. 7 is a schematic diagram showing a positional relationship between first and second eccentric cams.

FIG. 8 is a schematic diagram showing the force on the drive shaft during operation.

FIG. 9 is a sectional view showing a conventional horizontally opposed radial plunger type pump.

FIG. 10 is a schematic diagram showing the relationship between the instantaneous discharge amount and the rotation angle of the drive shaft when the number of plungers is even.

FIG. 11 is a schematic diagram showing a relationship between an instantaneous discharge amount and a rotation angle of a shaft when the number of plungers is an odd number.

FIG. 12 is a front view of a conventional radial plunger pump having three plungers.

FIG. 13 is a left side view of FIG.

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

[Explanation of symbols]

 9 Cam chamber 11 Drive shaft 12 Plunger 13 Plunger housing 25 Eccentric cam

Claims (1)

(57) [Claims] 1. A radial plunger type pump having three operating plungers radially arranged around a cam chamber of a plunger housing and driven by a drive shaft projecting into the cam chamber to perform a stroke operation sequentially.
The first and second actuation plungers are arranged on the first plane at an angle of 120 ° about the axis of the drive shaft, and are vertically arranged on a second plane parallel to the first plane at a predetermined interval. A third operating plunger whose mapping is at an angle of 60 ° with respect to the axis of the first and second operating plungers and the axis of the drive shaft, respectively, is disposed on the drive shaft, and the tip of the first and second operating plungers is disposed on the drive shaft. And a second eccentric cam acting in series with the first eccentric cam and having a phase shift of 180 ° and acting on the distal end of the third operating plunger. Radial plunger pump.