KR20040007918A - Solenoid valve for brake system - Google Patents

Abstract

PURPOSE: A solenoid valve for a brake system is provided to easily open and close the valve with little power even if large braking pressure is applied on an inlet by gradually opening and closing the valve at two steps through a spool mounted to the lower of an armature. CONSTITUTION: A solenoid valve for a brake system is composed of a valve housing(30), an armature(43), a spool(50), a hollow spool guiding member(60), a valve seat unit(36), and a spool returning spring(54). The valve housing includes an outlet(32) communicated with passages in a modulator block(20) and formed by an end of a hollow part(34) longitudinally arranged in the center and an inlet(31) for fluid formed at the periphery. The armature has a plunger(44) for entering the hollow part of the valve housing to move back and forth by electrical force and open and close the passage between the inlet and outlet. The spool is mounted in the hollow part to move forward and backward and formed with a first orifice(51) of a predetermined diameter opened and closed by movements of the plunger in the center. Insides of both ends of the hollow spool guiding member are contacted to outsides of the plunger and the spool, respectively, to guide movements of the spool. The valve seat is contacted to or separated from the end of the spool to open and close the outlet and formed with a step in the hollow part of the valve housing and a second orifice(37) larger than an inner diameter of the first orifice in the center. The spool returning spring pressurizes the spool toward the plunger.

Description

Solenoid Valve for Brake System {SOLENOID VALVE FOR BRAKE SYSTEM}

The present invention relates to a solenoid valve for a brake system, and more particularly, a solenoid for a brake system in which a flow path is opened and closed in two stages so that the valve can be easily opened and closed even when a large braking pressure is applied, and the opening degree of the flow path can be increased. It is about a valve.

In general, an anti-lock brake system for a vehicle is installed in the middle of a brake hydraulic line to control and control the braking pressure applied to the wheel side, and includes a plurality of solenoid valves that open and close the flow path according to a control signal. .

As shown in FIG. 1, the solenoid valve for the brake system is press-fitted into the valve coupling hole 14 of the modulator block 13 and has a hollow having an inlet 3 and an outlet 4 for the flow of fluid. Valve housing (1).

At one end of the valve housing 1, a cylindrical sleeve 6 is engaged so that the armature 5 installed therein can be retracted, and the open end of the sleeve 6 is closed at the open end of the sleeve 6. At the same time, the valve core 7 for advancing and retracting the armature 5 is engaged. In addition, the armature (5) is a valve seat provided in the hollow portion (2) of the valve housing (1) is provided with a plunger (5a) integrally provided at one end thereof to open and close the orifice (8a) of the valve seat (8) through a forward and backward movement ( 8) side.

Between the armature 5 and the valve core 7 is provided a restoring spring 9 for imparting elastic restoring force to the armature 5 so that the armature 5 keeps the orifice 8a normally closed. 6) and an excitation coil 10 for advancing and retracting the armature 5 on the outside of the valve core 7.

Such a solenoid valve generates a magnetic force between the valve core 7 and the armature 5 when power is applied to the excitation coil 10, and the armature valve moves toward the valve core 7 due to the magnetic force. Open the orifice 8a of (8). And when the power is not applied to the excitation coil 10, the magnetic force is released, the orifice (8a) is closed as the armature (5) is returned to its original state by the elasticity of the restoring spring (9).

However, such a conventional solenoid valve has a pressure difference between the inlet 3 side and the outlet 4 side when the pressure on the inlet 3 side is large when the plunger 5a of the armature 5 closes the orifice 8a. Since the initial operation of the amateur 5 is not smooth, there is a drawback in that a large magnetic force is required to open the orifice 8a by operating the amateur 5.

In addition, in order to obtain a rapid increase in pressure through the opening and closing operation of the solenoid valve in a conventional brake system, the cross-sectional area (opening degree of the flow path) of the orifice 8a must be increased to increase the flow rate of the solenoid valve. The larger the cross-sectional area, the larger the pressure difference between the inlet 3 side and the outlet 4 side, so that a large force is required to open the valve, and the opening and closing operation of the valve is unstable. Therefore, in the related art, a large force (magnetic force) is applied to the armature 5 to smoothly open and close the valve, but in this case, the volume of the excitation coil 10 is increased to generate a large magnetic force as well as a large operation noise of the valve. There was a problem that had to grow.

The present invention is to solve such problems, an object of the present invention is to open and close the valve in two stages in order to easily open and close with a small force even when a large braking pressure is applied to the inlet of the valve, It is to provide a solenoid valve for a brake system to increase the opening degree to enable a rapid pressure rise in the hydraulic line.

1 is a cross-sectional view showing the configuration of a conventional solenoid valve.

2 is a cross-sectional view showing the configuration of a solenoid valve according to the present invention.

3 is an exploded perspective view showing the configuration of a spool of the solenoid valve according to the present invention.

Figure 4 is a detailed cross-sectional view showing the opening and closing operation of the solenoid valve according to the present invention, showing a state in which the first orifice is opened first.

Figure 5 is a detailed cross-sectional view showing the opening and closing operation of the solenoid valve according to the present invention, showing a state in which the second orifice is open.

6 is a cross-sectional view showing the configuration of a solenoid valve according to the present invention, showing another embodiment.

Explanation of symbols on the main parts of the drawings

20: modulator block, 21: valve coupling groove,

30: valve housing, 31: inlet,

32: outlet, 34: hollow portion,

36: valve seat portion, 37: second orifice,

38: sealing member. 42: valve core,

43: amateur, 44: plunger,

45: female coil, 46: restoring spring,

50: spool, 51: first orifice,

54: spool restoring spring, 60: spool guide member,

61: communication.

A solenoid valve for a brake system according to the present invention for achieving the above object is, the one end of the hollow portion formed in the longitudinal direction at the center forms an outlet communicating with the flow path in the modulator block, and the valve housing formed with the inlet of the fluid around the ; An armature having a plunger which enters into the hollow part of the valve housing to open and close the flow path between the inlet and the outlet while retreating by an electric force; A spool installed in the hollow portion of the valve housing and having a first orifice having a predetermined diameter opened and closed by a retracting operation of the plunger at a central portion thereof; A hollow spool guide member coupled to the inner surfaces of both ends of the spool in close contact with the outer surface of the plunger to guide the advancement of the spool; A valve seat portion formed to have a step on an inner surface of the hollow portion of the valve housing so as to be opened or closed while contacting or spaced apart from an end of the spool, and having a second orifice formed at a center thereof larger than an inner diameter of the first orifice; And a spool restoring spring for urging the spool toward the plunger.

In addition, the spool guide member is characterized in that one end inner surface is fixed to the outer surface of the spool and the other end inner surface is slidably coupled to the outer surface of the plunger.

In addition, at least one communication passage is formed around the spool guide member in a radial direction such that the first orifice communicates with the inlet.

In addition, the inner diameter of the hollow portion of the valve housing to allow the flow of fluid when the spool is spaced apart from the valve seat portion while forming a space for installing the spool restoring spring on the outer surface of the spool side of the valve seat portion. Characterized in that the spring coupling portion formed to have a smaller outer diameter is provided.

Hereinafter, with reference to the accompanying drawings a preferred embodiment according to the present invention will be described in detail.

As shown in FIG. 2, the solenoid valve for the brake system according to the present invention is press-fitted into the valve coupling hole 21 of the modulator block 20 in which a plurality of flow paths 20a and 20b are formed, and the inlet port ( 31 and outlet 32 are provided with a hollow valve housing 30 in communication with flow paths 20a and 20b in modulator block 20, respectively. At this time, the valve housing 30 is installed so that the inlet 31 formed around the communication with the one side flow path 20a of the modulator block 20, the inlet 31 is provided with a filter 33 for filtering foreign matters. One end of the hollow portion 34 formed in the longitudinal direction at the center forms an outlet 32 communicating with the other side flow path 20b of the modulator block 20.

In addition, the outer surface of the valve housing 30 is formed in a different outer diameter so that the upper outer surface 30a and the lower outer surface 30b on the drawing has a predetermined step, the upper outer surface 30a and the lower outer surface 30b is a valve coupling hole ( 21) is press-fit to the inner surface of That is, when the valve housing 30 is mounted in the valve coupling hole 21 of the modulator block 20, the inner surface of the valve coupling hole 21 is formed by the upper outer surface 30a and the lower outer surface 30b of the valve housing 30. The upper outer surface 30a and the lower outer surface 30b of the valve housing 30 are fixed in a state in which airtightness is maintained in the valve engaging hole 21 by being press-fitted while being deformed by a predetermined amount.

In addition, one end of the hollow sleeve 41 provided in a cylindrical shape is coupled to the outer surface of the upper end of the valve housing 30, and the magnetic valve core 42 is coupled to the other open end of the sleeve 41. And the inside of the sleeve 41 is provided with a cylindrical arm 43 which can be moved up and down to open and close the flow path in the valve housing 30. At this time, the armature 43 is slidably supported on the inner surface of the sleeve 41, the lower portion is made of a plunger 44 smaller than the diameter of the upper portion extends into the hollow portion 34 of the valve housing 30. And the lower end of the plunger 44 is coupled to the opening and closing ball 44a for opening and closing of the flow path.

On the outside of the sleeve 41 and the valve core 42, an excitation coil 45 for advancing and retracting the armature 43 in the sleeve 41 is provided, and the upper portion of the armature 43 in the sleeve 41 and the valve core are provided. Between the 42 the restoring spring 46 is provided to elastically support the armature 43 so as to push the armature 43 toward the valve housing 30 when no power is applied to the excitation coil 45. In the hollow part 34 of the valve housing 30, a spool 50 is provided to advance and retract the inside of the hollow part 34 so that the flow path of the valve can be sequentially opened and closed in two stages.

As shown in FIGS. 3 and 4, the spool 50 is slidably supported on the inner surface of the hollow part 34 of the valve housing 30, and the center of the spool 50 is vertically extended to allow fluid flow. It is provided in a cylindrical shape. In addition, a first orifice 51 having a predetermined diameter is formed in the upper central portion of the spool 50 to control the flow of the fluid and to open and close the valve.

In addition, between the outer surface of the plunger 44 and the upper outer surface of the spool 50, the inner surface of both ends thereof is fitted to the outer surface of the plunger 44 and the upper outer surface of the spool 50 so that the forward and backward movement of the spool 50 can be guided. Cylindrical spool guide member 60 to be installed is provided. At this time, the lower inner surface of the spool guide member 60 is fixed to the outer surface of the spool 50 and the upper inner surface is slidably supported on the outer surface of the plunger 44. This allows the spool 50 to retreat separately while being slidably supported on the outer surface of the plunger 44 through the spool guide member 60 when the plunger 44 is moved back and forth with the armature 43. The center of the plunger 44 and the center of the spool 50 are always kept in the same state so that the opening and closing of the first orifice 51 through the opening and closing ball 44a of the plunger 44 is performed accurately.

In addition, the circumference of the spool guide member 60 is formed with a communication passage 61 penetrated in the radial direction so that the fluid flowing into the inlet 31 of the valve housing 30 flows toward the first orifice 51.

In addition, in the hollow portion 34 of the valve housing 30 in contact with the lower end of the spool 50, the first orifice 51 may be contacted or spaced apart from the lower end of the spool 50 when the spool 50 is advanced. Separately, the valve seat portion 36 is provided to open and close the outlet 32. The valve seat portion 36 is formed of a stepped jaw integrally formed on the inner surface of the hollow portion 34, and a second orifice 37 having a much larger inner diameter than the first orifice 51 is formed at the center thereof. do.

In addition, the outer diameter of the lower side of the spool 50 is smaller than the inner diameter of the hollow portion 34 of the valve housing 30 so that the spool restoring spring 54 for pressing the spool 50 toward the armature 43 can be installed. A stepped spring engaging portion 52 of size is formed. At this time, the spool restoring spring 54 is made of a conventional coiled compression spring fitted to the outer surface of the spring coupling portion 52, the upper end is supported by the jaw 53 of the outer surface of the spool 50 and the lower end of the valve seat portion ( 36) is supported on the upper surface. This configuration allows a space for the installation of the spool restoring spring 54 to be formed between the inner surface of the hollow portion 34 of the valve housing 30 and the outer surface of the spring coupling portion 52 of the spool 50. When 50 is raised, the fluid flowing through the inlet 31 of the valve housing 30 can flow directly toward the second orifice 37 through the space outside the spring coupling portion 52 (FIG. 5). Reference).

In addition, the elasticity of the aforementioned spool restoring spring 54 is smaller than the elasticity of the restoring spring 46 that pushes the armature 43. This is because the first orifice 51 and the second orifice 37 are closed while the plunger 44 and the spool 50 are lowered by the elasticity of the restoring spring 46 when no power is applied to the excitation coil 45. To do so.

On the other hand, Figure 6 shows another embodiment of the present invention, the upper outer surface (30a) of the valve housing 30 when the inner surface of the valve coupling hole 21 is deformed by a predetermined amount when pressed into the inner surface of the valve coupling hole 21 As a result, it is press-fitted and fixed in a state of maintaining airtightness, and the lower outer surface 30b of the valve housing 30 is coupled in a state of airtightness through a ring-shaped sealing member 38. Other configurations are the same as those described above.

The following describes the opening and closing operation of the solenoid valve for a brake system according to the present invention of such a configuration.

When power is not applied to the excitation coil 45, as shown in FIG. 2, the restoring spring 46 overcomes the elasticity of the spool restoring spring 54 and pushes the armature 43 toward the spool 50. The first orifice 51 is closed through the opening / closing ball 44a at the bottom of the plunger 44, and the second orifice 37 is maintained closed through the lower end of the spool 50.

When power is applied to the excitation coil 45 in this state, the flow path of the valve is opened while the armature 43 moves toward the valve core 42 by the magnetic force generated between the armature 43 and the valve core 42. At this time, since a high braking pressure is applied to the inlet 31 of the valve housing 30, the pressure acting on the spool 50 due to the pressure difference between the inlet 31 and the outlet 32 of the valve housing 30. 4, the opening and closing ball 44a is spaced apart from the first orifice 51 while the plunger 44 is raised before the spool 50, as shown in FIG. In this case, while the first orifice 51 is first opened, the fluid introduced into the inlet 31 flows toward the outlet 32 through the first orifice 51.

When the fluid flowing through the first orifice 51 of the spool 50 flows more than a predetermined amount toward the outlet 32, the pressure difference between the inlet 31 and the outlet 32 is reduced, as shown in FIG. 5. Likewise, as the spool 50 is secondarily raised by the elasticity of the spool restoring spring 54, the lower end of the spool 50 is spaced apart from the valve seat part 36. That is, in this case, since the fluid introduced into the inlet 31 flows directly toward the outlet 32 through the second orifice 37 having a large diameter, the fluid flows smoothly as the flow path is greatly expanded, so that the hydraulic line of the hydraulic line toward the outlet 32 can be quickly moved. Pressure rise is possible.

As such, the present invention opens the valve flow path through the two-step operation by the sequential rise of the plunger 44 and the spool 50, so that a small force even in a situation where a large pressure difference exists between the inlet 31 and the outlet 32 is present. Since the valve can be opened, the volume of the excitation coil 45 can be reduced, and since the flow path is greatly enlarged through the second orifice 37, the pressure rise of the hydraulic line toward the outlet 32 is possible. In addition, when the opening and closing is made, the spool 50 is guided by the spool guide member 60 which is slidably supported on the outer surface of the plunger 44 so that the first orifice 51 and the second orifice 37 are accurate. Opening and closing is done.

In addition, in the present invention, when the pressure difference between the inlet 31 side and the outlet 32 side operates in the direction in which the armature 43 is opened, the lower end of the spool 50 is caused by the elasticity of the spool restoring spring 54. Since it opens immediately, opening of the flow path is made faster.

As described above in detail, the solenoid valve for the brake system according to the present invention is opened and closed in two stages through the spool installed in the lower part of the amateur, so that even with a small force even when a large braking pressure is applied to the inlet side The valve can be easily opened and closed.

In addition, the present invention has the effect of reducing the volume of the excitation coil for the operation of the amateur since the valve can be opened and closed with a small force.

In addition, the present invention has the effect that the fluid flows into the inlet through the upward movement of the spool flows directly to the outlet through the second orifice having a large diameter to enable a rapid pressure rise of the hydraulic line on the outlet side.

In addition, the present invention has an effect that the opening and closing of the first orifice and the second orifice is accurately made because the spool advancing in the valve housing is guided through the spool guide member.

Claims (6)

A valve housing having one end of the hollow portion formed in the longitudinal direction at the center thereof and having an outlet for communicating with a flow path in the modulator block, the inlet for fluid being formed around the valve housing; An armature having a plunger which enters into the hollow part of the valve housing to open and close the flow path between the inlet and the outlet while retreating by an electric force; A spool installed in the hollow portion of the valve housing and having a first orifice having a predetermined diameter opened and closed by a retracting operation of the plunger at a central portion thereof; Hollow spool guiding members coupled to inner surfaces of both ends of the spool to closely contact the outer surface of the plunger and the outer surface of the spool so as to guide the advancement of the spool; A valve seat portion formed to have a step on an inner surface of the hollow portion of the valve housing so as to be opened or closed while contacting or spaced apart from an end of the spool, and having a second orifice formed at a center thereof larger than an inner diameter of the first orifice; And a spool restoring spring for pressurizing the spool toward the plunger. The method of claim 1, The spool guide member is a solenoid valve for a brake system, characterized in that one end inner surface is fixed to the outer surface of the spool and the other end inner surface is slidably coupled to the outer surface of the plunger. The method of claim 2, The circumference of the spool guide member is a solenoid valve for a brake system, characterized in that at least one communication passage penetrated in the radial direction so that the first orifice and the inlet communicate. The method of claim 1, The spool outer surface of the valve seat portion has a space for the installation of the spool restoring spring and at the same time the flow of the fluid when the spool is separated from the valve seat portion to allow the flow of fluid than the inner diameter of the hollow portion of the valve housing Solenoid valve for a brake system, characterized in that the spring coupling portion formed to have a small outer diameter is provided. The method of claim 1, The valve housing is the solenoid valve for the brake system, characterized in that the upper and lower parts of the outer surface is press-fitted to maintain the airtight in the valve coupling hole formed in the modulator block. The method of claim 1, The valve housing is the solenoid for the brake system, characterized in that the upper part of the outer surface is press-fitted in the valve coupling hole formed in the modulator block, the lower part of the outer surface is coupled to the valve coupling hole inner surface while maintaining an airtight state through a sealing member. valve.