KR100784372B1 - Damping force variable valve and shock absorber using same - Google Patents

Abstract

The damping force variable valve installed in the damping force variable shock absorber has a cross-sectional area control member for changing the cross-sectional area of the variable orifice, a solenoid member for adjusting the position of the cross-sectional area control member, and a reaction force against the cross-sectional area control member in a direction opposite to the thrust of the solenoid member. It includes a leaf spring to act.

Description

DAMPING FORCE VARIABLE VALVE AND SHOCK ABSORBER USING SAME with Variable Damping and Variable Damping Valves

1 is a cross-sectional view showing a shock absorber equipped with a damping force variable valve according to the prior art.

Figure 2 is a cross-sectional view showing the structure of a damping force variable valve according to the prior art.

Figure 3 is a cross-sectional view showing the structure of a damping force variable valve according to the present invention.

4 is a plan view of a leaf spring used in the damping force variable valve according to the present invention.

<Description of the symbols for the main parts of the drawings>

40: damping force variable valve 41: spool

41a, 41b: Slit 42: Solenoid member

43: spool rod 43a, 43b, 43c: connection port

45, 47: ring disc 46: lower retainer

46a, 46b: connection port 48: upper retainer

50: leaf spring 51: plug

60, 61, 63: hydraulic chamber 62: control chamber

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a damping force variable shock absorber equipped with a damping force variable valve and a damping force variable valve for controlling a damping force used in an automobile. More specifically, a leaf spring is used as an elastic member used in a damping force variable valve. The present invention relates to a damping force variable shock absorber equipped with a damping force variable valve and a damping force variable valve capable of reducing the axial length of the entire valve and stably securing the flow path.

In general, vehicle suspensions must adequately control the damping force in relation to the relative movement of the body and the wheels. For example, the damping force variable shock absorber including a damping force variable valve can reduce the damping force during normal driving of the vehicle, thereby absorbing vibration caused by unevenness of the road surface and improving riding comfort. On the other hand, when turning, accelerating, braking, driving at high speeds, etc., the damping force can be increased, and the attitude change of the vehicle body can be suppressed to improve steering stability.

However, since the wheel movement requires a quick response of 10 Hz or more, the mechanical valve mechanism inside the shock absorber can quickly adjust the damping force according to the relative movement of the vehicle body and the wheel, and the compression and rebound strokes. The development of a valve capable of controlling the damping force characteristics separately at the time has been promoted.

The damping force variable valve of the existing suspension system is divided into a normal type variable valve and a reverse type variable valve according to the damping force control method according to the movement of the vehicle. Reverse type variable valve is characterized by controlling the compression and tension stroke as a separate valve according to the movement of the vehicle. Thus, the reverse type variable valve generates a small damping force in the tension stroke and a large damping force in the compression stroke, or a large damping force in the tension stroke and a small damping force in the compression stroke. However, since the reverse type variable valve uses a separate valve, the production cost is expensive, and the size of the reverse type variable valve is relatively large due to the use of additional valves.

Normally variable valves use a single valve to control both damping forces during compression and tension strokes. Therefore, the normal variable valve generates either a large damping force or a small damping force both in the tension stroke and the compression stroke.

1 is a cross-sectional view showing the structure of a variable shock absorber 1 equipped with a normal damping force variable valve according to the prior art. The inside of the cylinder 10 is partitioned into the tension chamber 2 and the compression chamber 3 by the piston 11 which moves up and down in the cylinder 10. In addition, one end is connected to the piston 11 and the other end is extended to the piston rod 12 and the reservoir 13 to compensate for the volume change in the cylinder 10 according to the vertical movement of the piston rod 12 Is installed in communication with the cylinder (10). A valve 14 for the flow of oil between the tension chamber 2 and the compression chamber 3 is provided in the piston 11, and a valve 15 for the flow of oil between the reservoir 13 and the compression chamber 3. ) Is installed at the bottom of shock absorber (1). One or more of the valves 14 and 15 to be installed may be used as a check valve for allowing oil to flow in one direction without generating damping force and a damping valve for allowing oil to flow in one direction while generating damping force. Can be. The damping force variable valve 20 is provided at one end of the outer diameter portion of the base shell 16, which is the outer portion of the shock absorber 1.

2 is a cross-sectional view showing the structure of a normal type variable valve according to the prior art. The housing 21 of the damping force variable valve 20 is installed at one end of the outer shell portion of the base shell 16 of the shock absorber 1, and the solenoid valve 31 is installed at one end of the housing 21. In the coupling portion of the housing 21 and the shock absorber 1, a first flow path 22 connected to the tension chamber 2 and the compression chamber 3 of the shock absorber 1 and a second connection to the reservoir 13 are provided. The flow path 23 is formed.

Inside the housing 21, a spool 24 is installed to be reciprocated by the solenoid valve 31 in the longitudinal direction. The spool 24 has a plurality of stepped outer diameters in the vertical direction to allow flow of oil. On the outside of the spool 24 is installed a spool rod 25 for guiding the sliding movement of the spool 24, and at the outside of the spool rod 25, a retainer 27 having a connection port 26 is installed. The disk assembly 28 is installed between the upper retainer 27a and the lower retainer 27b.

According to the position of the spool 24, a cutout 24a is formed in a portion of the outer circumference of the spool 24 so as to selectively open the flow path into the spool rod 25, and correspondingly, the spool rod 25 ), A plurality of through holes 25a are formed. In addition, a coil spring 29 is installed above the spool 24 to lower the spool 24 raised by the solenoid valve 31 to the initial position.

When the damping force variable valve 20 of the shock absorber 1 configured as described above is traveling on a flat road at a constant speed, the flow path formed in the spool 24 and the spool rod 25 is blocked to have a single damping characteristic. When passing through a road surface or a bump, such as to change the position of the spool 24 to open the flow path formed in the spool 24 and the spool rod 25 to have a variable damping characteristics. That is, the damping characteristic of the damping force variable valve 20 changes according to the extent to which the flow path is opened by the movement of the spool 24.

The coil spring 29 is installed on the upper portion of the spool and serves to determine the position of the spool 24 together with the solenoid valve 31. However, the size of the coil spring 29 is relatively large, the size of the damping force variable valve as a whole becomes large, and there is a disadvantage that the mounting is poor. In addition, since the space occupied by the coil spring 29 is larger than that of the flow passage passing through the upper portion of the spool 24, there is a problem that the coil spring blocks the flow passage of the oil and acts as an element that hinders the flow of the oil.

Accordingly, an object of the present invention is to use a leaf spring as the spool spring, while sufficiently securing the flow path passing through the spool, while reducing the overall axial length of the damping force variable valve to reduce the mounting force and variable damping force variable valve To provide a shock absorber variable shock absorber equipped with a.

According to one embodiment of the present invention for achieving the above object, in the damping force variable valve installed in the variable damping force shock absorber, the cross-sectional area control member for changing the cross-sectional area of the variable orifice and the position of the cross-sectional area control member is adjusted A damping force variable valve is provided that includes a solenoid member and a leaf spring that exerts a reaction force against the cross-sectional area control member in a direction opposite to the thrust of the solenoid member.

According to another embodiment of the invention, in the damping force variable shock absorber equipped with a variable damping force valve, the damping force variable valve is a cross-sectional area control member for changing the cross-sectional area of the variable orifice, and the solenoid for adjusting the position of the cross-sectional area control member A damping force variable shock absorber is provided that includes a member and a leaf spring that exerts a reaction force against the cross-sectional area control member in a direction opposite to the thrust of the solenoid member.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, about the same part as a prior art, the same code | symbol is attached | subjected and unnecessary description is abbreviate | omitted.

3 is a cross-sectional view showing the structure of a damping force variable valve according to the present invention. Hereinafter, the structure of the damping force variable valve according to the present invention will be described.

The spool rod 43 for guiding the sliding movement of the spool 41 is coupled to the solenoid member 42 which changes the position of the spool 41, wherein the operating rod 44 of the solenoid member 42 is spooled. It is inserted into the rod 43. The spool rod 43 has a plurality of radial connecting ports 43a, 43b, 43c for connecting the hollow of the hollow and the spool rod 43 and the outside of the spool rod 43 for inserting the spool 41 at the center thereof. It includes. A ring disk 45 having a central hole for inserting the spool rod 43 and a slit of the circumferential portion, which serves as a fixing orifice, is connected to the spool rod 43 while being fitted to the spool rod 43.

 A lower retainer 46 having a central hole for inserting the spool rod 43 and serving to fix the position of the spool rod 43 is mounted on the ring disc 45 while being fitted to the spool rod 43. . The lower retainer 46 includes connecting ports 46a and 46b to allow the flow of oil.

A ring disk 47 which has a central hole and a slit for inserting the spool rod 43, partitions the high pressure side Ph and the control chamber 62, and serves as a main valve, is placed on the lower retainer 46. Is installed. An upper retainer 48 having a central hole for inserting the spool rod 43 and serving to fix the position of the spool rod 43 is mounted on the ring disc 47 while being fitted to the spool rod 43. . The upper retainer 48 includes connecting ports 48a and 48b to allow the flow of oil.

A spool 41 reciprocating by the solenoid member 42 is inserted into the hollow of the spool rod 43, and a disk-shaped spool spring (hereinafter referred to as a leaf spring) 50 is mounted on the spool 41. . A plug 51 for fixing the leaf spring 50 is installed on the leaf spring 50. By the nut 49, the aforementioned spool rod 43, lower retainer 46, upper retainer 48 and the like are connected in one unit.

The position of the spool 41 is elastically fixed by the compression spring (not shown) and the leaf spring 50 which press the rear end of the actuating rod 44 of the solenoid member 42. An upper retainer guide 53 is mounted to cover the upper retainer 48, with a gap between them sealed by an O ring 54.

In this embodiment, the case of adjusting the cross-sectional area of the variable orifice of the damping force variable valve using the spool has been described, but the present invention is not limited thereto, and includes a case of using another cross-sectional area adjusting member. In addition, in the present embodiment, the case where the position of the spool is adjusted using the solenoid member has been described, but other position adjusting means may be used.

Hereinafter, the flow of oil according to the structure of the damping force variable valve 40 described will be described.

The oil moves from the high pressure side Ph to the hydraulic chamber 60 formed by the upper retainer 48 and the ring disk 47 through the connection ports 48a and 48b of the upper retainer 48 by the movement of the piston. . The oil transferred to the hydraulic chamber 60 is moved into the spool rod 43 through the second variable orifice consisting of the connecting port 43a of the spool rod 43 and the upper slit 41a of the spool 41 and And it passes through the connection port 53 with the low pressure side Pl, and moves to the low pressure side Pl.

The oil moved to the hydraulic chamber 60 in the same manner is composed of the first variable orifice consisting of the slit of the ring disk 47, the connecting port 43b of the spool rod 43 and the lower slit 43b of the spool 41; It passes through the connection port 43c of the spool rod 43 one by one, and moves to the hydraulic chamber 61. Some of the moved oil exits to the low pressure side Pl through the circumferential slit (not shown) of the ring disk 45 constituting the fixed orifice. The oil that has not escaped to the fixed orifice travels to the control chamber 62 formed of the lower retainer 46 and the ring disk 47.

When the flow rate increases during the tension or compression stroke and the pressure difference between the high pressure side Ph and the control chamber 62 becomes large, the ring disk 47 is bent toward the control chamber by the force generated by the pressure difference. . That is, a gap may occur between the upper retainer 48 and the ring disk 47 according to the pressure on the high pressure side Ph, the pressure in the control chamber 62, and the preload of the initial ring disk 47. That is, the main valve is opened so that oil flows directly from the high pressure side Ph to the low pressure side Pl.

When the flow rate decreases during the tension or compression stroke, the pressure difference between the high pressure side Ph and the control chamber 62 becomes small, which causes the ring disk 47 to return to its original position according to the preload of the ring disk 47. This closes the main valve.

The main valve opens at a different pressure depending on the pressure of the control chamber 62, which is formed by the action of a first variable orifice installed upstream and a fixed orifice installed downstream. By controlling the area of the first variable orifice, the pressure in the control chamber 62 is increased to switch to hard mode. In addition, a second variable orifice is installed to allow a flow rate from the high pressure side Ph to the low pressure side Pl, and as the area of the first variable orifice increases, the area of the second variable orifice decreases, As the area decreases, the area of the second variable orifice increases. Through this, proper damping force characteristics can be obtained.

4 is a front view of the leaf spring 50 according to the present invention. 3 and 4, the disk-shaped leaf spring 50 has a circular hole 50a in the center portion, and the diameter of the circular hole 50a is set smaller than the diameter of the head 41c portion of the spool. The spool supports the head 41c portion. Since the oil can flow through the circular hole 50a of the leaf spring 50, the hollow part of the spool rod 43 in which the hydraulic chamber 63 and the spool 41 on the leaf spring 50 is located is located. There is no pressure difference.                     

The leaf spring 50 according to the present invention is suitable for controlling the position of the spool 41 which is not large in variation since the variation is small and high rigidity. In addition, by using the leaf spring 50 having a smaller axial length than the coil spring, the axial length of the entire damping force variable valve 40 is reduced, so that the damping force variable valve 40 and the damping force variable shock absorber equipped therewith can be mounted. Can improve. In addition, by using the leaf spring 50, it is possible to secure a sufficient flow path of oil passing through the upper portion of the spool 41, which the coil spring interfered with.

Meanwhile, in the above description of the present invention, specific embodiments have been described, but the present invention is not limited to the above-described embodiments, and those skilled in the art to which the present invention pertains will have the present invention described in the following claims. Various changes may be made without departing from the gist of the matter. Therefore, the scope of the invention should not be defined by the described embodiments, but should be defined by the claims.

As described above, the mounting spring of the shock absorber provided with the damping force variable valve and the damping force variable valve can be improved by reducing the axial length of the damping force variable valve using the leaf spring. In addition, it is possible to sufficiently secure the oil passage passing through the upper portion of the spool.

Claims (6)

In the damping force variable valve installed in the variable damping force shock absorber, A spool that changes the cross-sectional area of the variable orifice, Solenoid member for adjusting the position of the spool, And a leaf spring that is an elastic member that exerts a reaction force against the spool in a direction opposite to the thrust of the solenoid member. The method of claim 1, It is installed between the high pressure side and the low pressure side, and can be opened and closed according to the pressure of the high pressure side, the initial preload and the pressure of the control chamber, and when opened, the main valve to allow the flow of oil from the high pressure side to the low pressure side Wow, A first variable orifice formed between the high pressure side and the control chamber to control the pressure of the control chamber; A fixed orifice installed between the control chamber and the low pressure side, And a second variable orifice provided between said high pressure side and said low pressure side. The method according to claim 1 or 2, The leaf spring is variable damping force valve characterized in that it has a hole through which the oil can flow in the central portion. In a damping force variable shock absorber equipped with a damping force variable valve, The damping force variable valve is A spool that changes the cross-sectional area of the variable orifice, Solenoid member for adjusting the position of the spool, A shock absorber variable shock absorber comprising a leaf spring that is an elastic member that exerts a reaction force against the spool in a direction opposite to the thrust of the solenoid member. The method of claim 4, wherein It is installed between the high pressure side and the low pressure side, and can be opened and closed according to the pressure of the high pressure side, the initial preload and the pressure of the control chamber, and when opened, the main valve to allow the flow of oil from the high pressure side to the low pressure side Wow, A first variable orifice formed between the high pressure side and the control chamber to control the pressure of the control chamber; A fixed orifice installed between the control chamber and the low pressure side, And a second variable orifice provided between said high pressure side and said low pressure side. The method according to claim 4 or 5, The leaf spring has a variable damping force shock absorber, characterized in that it has a hole through which oil flows.

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