JPH0741898Y2 - Multi-system pump device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) This invention has a plurality of independent hydraulic systems that use pump pressure, such as a brake device including a hydro booster and an anti-skid control device. TECHNICAL FIELD The present invention relates to a multi-system pump device used for a vehicle, and particularly to a technique effective in preventing loss of hydraulic fluid.

(Prior Art) This type of multi-system pump device includes a number of pump action parts corresponding to the hydraulic system. Therefore, in order to reduce the space occupied by the pump device, a technique of driving a plurality of pump action parts by a common prime mover is already known.

In that technique, each pump action portion is arranged around the cam chamber inside the housing, and is pumped by an eccentric cam in the cam chamber. That is, each pump action portion includes a cylinder hole connected to the cam chamber, and a plunger that movably fits in the cylinder hole by partitioning the volume chamber, and each plunger rotates the eccentric cam in the cam chamber. Move according to. In that respect, when there are different hydraulic systems such as a hydrobooster and an antiskid controller (for example, Japanese Patent Laid-Open No. 63-166648), or in the same antiskid controller, multiple independent channels are used. In some cases (for example, JP-A-64-77768)
The same applies to any of the above.

(Problems to be Solved by the Invention) By the way, in the conventional technique, the suction passages of the pump action portions belonging to the respective hydraulic systems are provided separately around the respective plungers.

Therefore, in addition to the problem of complicated passage formation,
There is a risk of loss of hydraulic fluid. Regarding the latter, more specifically, when liquid leakage occurs between the plunger cylinders, the leaked liquid enters the cam chamber and becomes ineffective. Empirically, the liquid leakage frequently occurs in the guide portion of the reciprocating plunger, so that the liquid leakage into the cam chamber is the most problematic. As a result of the liquid leakage, the amount of hydraulic fluid in the reservoir will of course decrease.

This invention was made in response to the problem of liquid leakage as described above, and even if such a liquid leakage occurs, liquid loss in the reservoir supplying the hydraulic fluid to each hydraulic system will not occur. The purpose is to provide the technology.

(Summary of the Invention) In the present invention, the cam chamber serves as a communication passage for connecting the pump action section belonging to at least one hydraulic system and the reservoir side, and the pump action section belonging to the remaining hydraulic system. A communication passage for communicating with the reservoir side,
The cam chamber is provided separately from the cam chamber.

According to this, even if the liquid leak occurs, the leaked liquid is collected in the reservoir via the cam chamber, and the liquid loss as a whole can be prevented.

(Embodiment) FIG. 1 shows an overall circuit configuration of a brake device to which the present invention is applied, and is drawn mainly on a sectional structure of a pump portion. Further, FIG. 2 shows the arrangement of the pumps.

First, the portion of the brake circuit from the master cylinder to the wheel cylinders will be clarified with reference to FIG.

The brake circuit of the brake device 10 includes a tandem master cylinder 12 as a brake pressure generation source. The master cylinder 12 has a hydro booster 20 for assisting its operation and a reservoir 14 for accumulating the working fluid, which are integrated with each other. The hydro booster 20 is a known one including a supply valve 22 and a discharge valve 23 in addition to the cylinder body 21. This hydro booster 20 opens and closes the discharge valve 23 and supplies the supply valve 22 in response to the depression of the brake pedal 11.
Is closed to open, and the operation of the master cylinder 12 is assisted by receiving the supply of the pressure fluid from the auxiliary pressure source circuit described later.

The two brake circuits are front and rear piping.
A brake pipe 31 extends from one outlet 12a of the tandem type master cylinder 12 and is divided into two branch pipes 31a and 31b from the middle, and each branch pipe 31a and 31b is a wheel of the front brake 33FR and 33FL. Contact the cylinder. In addition, from the other discharge port 12b of the master cylinder 12,
Similarly, the brake pipe 32 extends and is also divided into two branch pipes 32a and 32b from the middle, and the respective branch pipes 32a and 32b communicate with the wheel cylinders of the rear brakes 33RR and 33RL.

And each branch pipe 31a, 31b; 32 of such a brake circuit
There is an anti-skid hydraulic pressure control device in the middle of a and 32b. Anti-skid hydraulic pressure control device is used for front and rear brakes 33FR, 3
The configuration is the same for 3FL; 33RR, 33RL. It has
In addition to the pumps described later, each branch pipe 31a, 31b; 32a, 32b
A 3-position 3-way solenoid switching valve 35 located in the middle of the valve, a brake slack control valve 36 connected in parallel to the solenoid switching valve 35, and a low pressure for storing the working fluid loosened through the solenoid switching valve 35. Includes reservoir 37. In this example, the low-pressure reservoir 37 has one left and right brake in common in the front and rear. The solenoid switching valve 35
Is a current control type switching valve, which responds to a control signal from an electronic controller (this controller receives signals from a wheel speed sensor or the like and controls each valve and pump based on the signal), which is not shown. Switches between holding, loosening, and packing states. The electromagnetic switching valve 35 is usually
It is at the loading (communication position) position shown in the figure.

Next, the auxiliary pressure source circuit that supplies hydraulic pressure to the hydro booster 20, the main body of which is the accumulator 40. As the accumulator 40, any of a bladder type, a piston type and a metal bellows type can be used, but in many cases, a bladder type is used. This Aki Yumulator
The reference numeral 40 receives the supply of the pressure liquid from the pump and accumulates the pressure liquid. Associated with the accumulator 40 is a pressure switch 42 and a relief valve 44. The pressure switch 42 is
The pressure acting amount in the accumulator 40 is detected by connecting to the middle of the discharge side pipe line 43 of the pump action part (hereinafter, also simply referred to as a pump). The accumulated pressure is the upper limit pressure,
Electrical contacts 42a, 42b, 42 for low and no pressure
It is known by the on-off state of c. The signals from the respective contacts of the pressure switch 42 are sent to a controller (not shown) and used for control to enable or disable the operation of the pump. On the other hand, the relief valve 44 is located in the middle of a pipe line 46 that connects the discharge side pipe line 43 and the suction side pipe line 45 of the pump. The relief valve 44 returns excessive hydraulic pressure to the reservoir 14 side through the conduit 45 when the temperature rises and the accumulated pressure in the accumulator 40 exceeds its capacity.

By the way, the brake device 10 includes an anti-skid pump for pressurizing the hydraulic fluid in the low-pressure reservoir 37, and the reservoir 14.
There are two types of pumps, a hydro booster pump that pressurizes the working fluid inside and sends it to the accumulator 40. Since these two types of pumps are provided in pairs, the total number of hydraulic systems for each pump action section is four. The four pump action parts as a whole share the same electric motor 50 as a prime mover, and also share their housings. A drive shaft 51 of the electric motor 50 extends inside the housing 54 from top to bottom in the drawing, and an eccentric cam 52 is supported in the middle of the drive shaft 51. The eccentric cam 52 serves as a master and drives the plunger of each pump as a slave.

Since there are two low-pressure reservoirs 37 in the anti-skid hydraulic pressure control device depending on the front and rear pipes, the anti-skid pump action parts are the first pump 61 and the second pump 62. Therefore, in the brake device 10, in consideration of the balance of the force around the cam, the other hydro-booster pump action portion is also made up of the first pump 71 and the second pump 72. Although FIG. 2 shows the arrangement of the pumps, the pumps are arranged in a cross shape, and the first pump and the second pump for both the antiskid and the hydro booster are arranged around one eccentric cam 52. And 180 ° apart from each other. Of course, there are two cams, and the first pump 61 and the second pump 62 for anti-skid are 180 ° around one of the cams.
It is also possible to arrange them separately and to arrange one or two hydro booster pumps around the other cam.

The structure itself of the two types of pumps is similar to the conventional one.
FIG. 1 shows a sectional structure of the pump portion displaced by 90 °. In the center of the housing 54, which is the main body,
There is a chamber 55 in which the drive shaft 51 of the electric motor 50 extends. The room 55
Is a cam chamber that houses the eccentric cam 52, and has four cylinder holes that are orthogonal to it. Each pair of cylinder holes is in a straight line.One of the cylinder holes 56 is provided with a hydro-booster pump 71, 72, and the other cylinder hole 58 is provided with an anti-skid pump 61, 62. There is.

Looking at the anti-skid pump 61 (the other pump 62 is also the same) located on the left side of the figure, there are cylinder members 63a and 63b which are integrated with each other by caulking in the cylinder hole 58. The cylinder members 63a and 63b are supported so that the plug 64 is sandwiched between the plug 64 and the stepped portion of the housing 54. Then, the integrated cylinder member 63a,
Inside the 63b, there are a pair of check valves 65a, 65b, and between them is a volume chamber 66 of the pump. This volume chamber 66 communicates with the discharge ports 61o and 62o of the housing 54 through the check valve 65a and the passage 67a provided in the cylinder member 63a on the one hand, and the check valve 65b and the passage in the plunger 68 on the other hand. The suction ports 61i and 62i are communicated with each other through 68a and the like. Therefore, when the plunger 68 reciprocates, the working fluid reaches the volume chamber 66 through the suction ports 61i, 62i, and the working fluid is pressurized in the volume chamber 66 and sent from the discharge ports 61o, 62o to the brake circuit. Then, the inside of the cylinder hole 58 following the suction ports 61i, 62i is provided with a seal ring 69a around the plunger 68 and the cylinder member 6.
A seal with the cam chamber 55 side is achieved by 9b. The suction ports 61i and 62i communicate with the low pressure reservoir 37 through the conduit 48 and the check valve 38, and the discharge ports 61o and 62o.
Brake line 31, 32 through line 49 and check valve 39.
Have been contacted.

On the other hand, the hydro booster pump 71 located on the right side of the figure.
As for (the other pump 72 is the same), there is a cylinder member 73 and a valve housing 74 in the cylinder hole 56, and one end of the valve housing 74 is provided with a cap member.
75 support. A check valve 76 is provided in the valve housing 74, and a volume chamber 78 is provided between the check valve 76 and the plunger 77. On the other hand, the volume chamber 78 passes through the check valve 76, the passage 74a provided in the cap member 74, etc., and the discharge port 71 of the housing 54 portion.
o, 72o, and on the other hand a passage 77a in the plunger 77,
It communicates with the suction port 71i through a cam chamber 55 or the like in the center of the housing 54. Then, when the plunger 77 reciprocates,
The working fluid reaches the volume chamber 78 through the suction port 71i, and the working fluid is pressurized in the volume chamber 78 and sent from the discharge ports 71o, 72o to the accumulator 40 side.

Pump outlets 71,72 for these hydro boosters 71
It goes without saying that o and 72o are connected to the accumulator 40 through the conduit 43, and the suction port 71i is connected to the reservoir 14 through the conduit 45. In the brake device 10, the electromagnetic switching valve 80 is connected while the suction port 71i and the reservoir 14 are connected.
There is. This switching valve 80 is a two-position valve and has a shut-off position A.
To the communication position B. The switching valve 80 is normally in the communication position B, but is controlled so as to switch to the cutoff position A when a predetermined pressure is accumulated in the accumulator 40 during antiskid control. Therefore, the antiskid start signal from the controller and the signal from the pressure switch 42 are used as the control signals for the switching valve 80, respectively. If the switching valve 80 is in the shut-off position A, the pump 14 for the hydro booster is installed from the reservoir 14 side.
Since no hydraulic fluid is supplied to 1,72, the operation of those pumps can be disabled.

Now, as I said before, pump 6 for anti-skid
Although the circumference of the plungers 68 of 1,62 is separated from the cam chamber 55 by the seal ring 69a, the cam chamber 55 is empirically determined.
It is extremely difficult to completely prevent the leakage of liquid. However, here, the cam chamber 55 is used as a communication passage for connecting the other hydro-booster pumps 71, 72 and the reservoir 14 side. Therefore, even if the liquid leaks from the anti-skid pumps 61 and 62 to the cam chamber 55, the leaked liquid will be pumped through the cam chamber 55 to the hydro booster pump.
71, 72 enters the hydraulic system to which the pump belongs, and can be eventually recovered to the reservoir 14 side with the operation of the pump, and liquid loss as a whole does not occur.

In the illustrated embodiment, the cam chamber 55 is used as a communication passage for both of the two hydro-booster pumps 71, 72, but if the cam chamber 55 is used as a communication passage for at least one pump. good.

(Effect of the Invention) According to this invention, since the cam chamber 55 is used as a communication passage for connecting the pump action portions 71, 72 belonging to at least one hydraulic system and the reservoir 14 side, the remaining liquid separated Even if liquid leaks from the pump action parts 61, 62 of the pressure system to the cam chamber 55, the leaked liquid can be recovered through the cam chamber 55, and the loss of the hydraulic fluid can be reliably prevented. Moreover, since the cam chamber 55 is used as the communication passage, the degree of freedom in forming the passage for the pump action portion can be increased.

[Brief description of drawings]

FIG. 1 is an overall view showing an embodiment of the present invention, and FIG. 2 is a view showing the arrangement of pumps. 10 …… Brake device, 12 …… Master cylinder, 14 …… Reservoir, 20 …… Hydro booster, 31,32 …… Brake piping, 52 …… Eccentric cam, 55 …… Cam chamber, 56,58 …… Cylinder hole , 66,78 …… Volume chamber, 68,77 …… Plunger, 61,6
2 …… Anti-skid pump (pump action part), 71, 72
...... Hydrogen booster pump (pump action part).

Claims (1)

[Scope of utility model registration request] 1. A plurality of pump action parts are provided around a cam chamber inside a housing, and each of these pump action parts defines a cylinder hole communicating with the cam chamber and a volume chamber defined in the cylinder hole. Including a plunger that fits freely,
Each plunger is movable according to the rotation of an eccentric cam in the cam chamber, and the plurality of volume chambers communicate with two or more hydraulic systems that consume pressure independently of each other, and the pump In a multi-system pump device in which each of the action parts receives supply of hydraulic fluid from a reservoir common to all of the hydraulic systems, in the cam chamber, the pump action part belonging to at least one hydraulic system and the reservoir side are provided. And a communication passage for connecting the pump action portion belonging to the remaining hydraulic system and the reservoir side,
A multi-system pump device provided separately from the cam chamber.