JPH04127872U - plunger pump - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain a plunger pump that can prevent the shaft itself from being deflected due to the inertial force of the eccentric cam portion of the shaft and improve the sound and vibration properties of the plunger pump. [Structure] Plural rows of plungers 4 are arranged in the axial direction of the shaft 3 on the outer peripheral side of the eccentric cams 9 and 90 formed on the shaft 3.
40 are arranged radially to form plunger rows, eccentric cams 9 and 90 corresponding to each plunger row are provided on the shaft 3, and the maximum lift positions of the eccentric cams 9 and 90 are arranged at equal intervals in the circumferential direction. has been done.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is useful for oils used in automobile power steering devices and suspensions, for example. This invention relates to a plunger pump used as a pressure source.

0002

[Conventional technology]

In general, power steering devices for automobiles use power from the engine to power the plastic. Some drive the engine pump and use its hydraulic pressure as a steering assist force. This type of plunger pump includes, for example, as shown in Japanese Patent Application Laid-open No. 60-60370. In addition, multiple plungers are arranged radially around the outer circumference of an eccentric cam formed on the shaft. There is known prior art that does this.

0003 In order to increase the flow rate and improve the performance of the plunger pump, , multiple plungers are arranged in the axial direction of the shaft on the outer circumference of the eccentric cam on the shaft. Some plungers are arranged in multiple rows.

0004

[Problem that the idea aims to solve]

However, in the conventional plunger pump described above, each plunger row has a In contrast, one eccentric cam formed on the shaft was used. For this purpose, each program The maximum and minimum lift parts of the eccentric cam relative to the plunger row are located in the same direction. The plunger pump was operated at high speed by the engine. As a result, the shaft itself flexes due to the inertia of the eccentric cam part of the shaft, causing the plunger port to bend. There were problems such as the pump causing vibration and noise.

[0005] The purpose of this invention is to solve the above-mentioned conventional problems by Preventing the shaft itself from deflecting due to inertia force improves the sound and vibration properties of the plunger pump It is possible to get a plunger pump.

[0006]

[Means to solve the problem]

To achieve this objective, the present invention provides a plurality of eccentrics corresponding to each row of plungers. A cam is installed on each shaft, and the maximum lift position of the above eccentric cam is set in the circumferential direction. They are arranged at equal intervals.

[0007]

[Effect]

Based on this configuration, in the plunger pump according to the present invention, each eccentric cam The maximum lift portions of the shaft are arranged at equal intervals in the circumferential direction, allowing the shaft to rotate at high speed. Even if it rotates, the inertial force caused by the eccentric cam will be almost balanced against the center of rotation, and the rotation will continue. Deflection of the shaft itself due to rolling force is suppressed, reducing vibration and noise generation. can.

[0008]

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings.

[0009] FIG. 1 is a vertical sectional view of a plunger pump showing a first embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II in FIG. 1. FIG. In the figure, code 1 is a radial plunger pump This is an example of a plunger pump, and inside the housing 2 on the plunger pump 1 side A shaft 3 is disposed at the center of the shaft and extends in the front-rear direction. The front end is connected to the housing 2 through a bearing 5, and the middle is connected to the housing 2 through a bearing metal 6. is rotatably supported. Then, on the front side of the bearing 5, the seal ring 7 and the pad The part that protrudes forward from the housing 2, which is closed liquid-tight with the housing 8, is shown in the figure. It is designed to be rotationally driven by the crankshaft of an engine (not shown).

0010 A pair of eccentric cams are provided at the intermediate outer peripheral portion of the shaft 3 in the housing 2. 9 and 90 are provided. This pair of eccentric cams 9 and 90 has its maximum lift 90a is spaced equally in the circumferential direction with respect to the portion 9a, and 90b is spaced equally with respect to the minimum lift portion 9b. It is placed in the gap. Each of the eccentric cams 9 and 90 has an annular slot on its outer periphery. The coupling ring 10 is fitted, and the outer periphery of the eccentric cams 9 and 90 is connected to the housing. A plurality of plunger housing holes formed in a plurality of rows, for example two rows, in the ring 2 are each provided with a plurality of plunger housing holes. Plungers 4 and 40 are arranged in the axial direction of the shaft 3, and each plunger It constitutes a column of columns. Therefore, the maximum lift portions 9b, 90b of the eccentric cams 9, 90 are They are arranged at equal intervals in the circumferential direction, so they can be arranged at 180° intervals. Become.

[0011] The plungers 4 and 40 are reciprocated by the rotation of the eccentric cams 9 and 90. The piston 11 is operated when the housing 2 is opened. It is controlled by a plug 12 whose mouth end is closed. And each piston 1 above A coil spring 14 is inserted into the coil spring 1. The biasing force causes the piston 11 to come into contact with the slip rings 10 of the eccentric cams 9 and 90. It is in a state of being

0012 Further, each piston 11 is formed with a suction hole 11a, and the eccentric cam 9 and When the piston 11 is actuated by Oil flows into the piston 11 through a, and the oil is formed in the upper part of each piston 11. A discharge (not shown) is supplied from the suction chamber 17 via a discharge passage 18 and a check valve 19. It performs a pumping action such as hydraulic oil being forced into the outlet chamber.

[0013] The illustrated embodiment has the above structure, so the pump action is as follows. I can.

[0014] First, when the engine starts and the shaft 3 rotates, the plunger pump 1 is driven. be moved. Then, during the suction stroke of each piston 11, the oil suction portion 16 of the pump The oil inserted into the piston 11 is continuously discharged through the suction hole 11a. It flows out from the suction chamber 17 into the discharge chamber.

[0015] Therefore, such an operation is performed in a time series corresponding to the rotational position of the eccentric cams 9 and 90. Each piston 11 is sequentially controlled in a row, and the oil sucked into the piston 11 is Sudden pressure fluctuations such as negative pressure peaks occur without a sudden inflow of Since there is no noise, intake noise is reduced. Also, when the shaft 3 rotates, the eccentric cams 9, 9 Since the maximum lift positions of 0 and 9 are arranged at equal intervals in the circumferential direction, the eccentric cam 9 , 90 is suppressed from deflecting the shaft 3 due to the inertial force. In addition, although the above embodiment has been described with two plunger rows, the invention is not limited to this. It can be applied to devices with multiple rows of plungers, for example, if there are three rows of plungers. In the case of rows, the eccentricity places the maximum lift position on the circumference of the shaft with a gap of 120°. You can configure it to do so.

[0016]

[Effect of the idea]

As explained above, according to the plunger pump according to the present invention, each of the plurality of plungers Eccentric cams corresponding to the connector rows are provided on the shaft, and the maximum Since the lift positions are arranged at equal intervals in the circumferential direction, the shaft rotates at high speed. Also, the inertial force caused by the eccentric cam is almost balanced against the center of rotation, and the rotational force This suppresses the deflection of the shaft itself, reducing the generation of vibration and noise. .

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a plunger pump showing a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 in FIG. 1;

[Explanation of symbols]

1 plunger pump 2 Housing 3 Shaft 4 Plunger (plunger row) 9 Eccentric cam 40 plunger (plunger row) 90 eccentric cam

Claims (1)

[Scope of utility model registration request] 1. A plunger pump comprising a plurality of rows of plungers arranged in the axial direction of the shaft on the outer peripheral side of an eccentric cam formed on a shaft, wherein an eccentric cam corresponding to each row of plungers is arranged on the shaft. A plunger pump characterized in that the maximum lift positions of the eccentric cams are arranged at equal intervals in the circumferential direction.