KR20200017856A - Damping force controlling shock absorber - Google Patents

Abstract

According to the present invention, a variable damping force shock absorber comprises: a cylinder having an inner tube and an outer tube filled with a fluid; a housing coupled to a lower end of a piston rod placed inside the inner tube and forming a connection passage therein; a first piston valve coupled to the outside of the housing to define a compression chamber and a tension chamber; a magnet member provided inside the housing; a second piston valve provided inside the housing and placed under the magnet member; and a plunger installed between the magnet member and the second piston valve and moved by a magnetic force of the magnet member to open and close the connection passage. When moving in a hard mode, the plunger closes the connecting passage to have the fluid pass through the first piston valve, and when moving in a soft mode, the plunger opens the connecting passage to have the fluid pass through the second piston valve.

Description

Damping force variable shock absorber {DAMPING FORCE CONTROLLING SHOCK ABSORBER}

The present invention relates to a damping force variable shock absorber provided in a vehicle to mitigate an impact transmitted from the ground.

In general, the shock absorber is installed in a moving means such as a car, and absorbs and cushions vibrations or shocks received from the road surface while driving to improve riding comfort. Here, the shock absorber includes a cylinder and a piston rod installed in the cylinder so as to be compressible and extendable, and the cylinder and the piston rod are respectively coupled to the vehicle body or the wheel or the axle.

When the damping force is set to a low damping force, the shock absorber may improve vibrations by absorbing vibration caused by unevenness of the road surface while driving, whereas when the damping force is set to a high damping force, the posture change of the vehicle body is suppressed to improve steering stability. .

Therefore, the damping force variable valve is installed on one side of the shock absorber to adjust the damping force characteristics appropriately, and the damping force variable shock absorber that can adjust the damping force characteristics appropriately to improve the riding comfort and steering stability according to the road surface and driving conditions is developed. It became.

The conventional damping force variable shock absorber has a structure in which hard flow paths and soft flow paths are selected by selectively opening and closing a plurality of flow paths formed in the spool guide through the variable position of most spools. That is, by selectively adjusting the opening and closing states of the hard flow path and the soft flow path formed in the spool guide, the hard damping force or the soft damping force is selectively generated.

To this end, the conventional damping force variable shock absorber individually forms a back pressure flow path for hard damping force formation and a soft flow path for soft damping force formation.

Such a conventional damping force variable shock absorber includes a piston for dividing a cylinder into a compression chamber and a tension chamber, a back pressure chamber for forming back pressure during compression and tension stroke, and a connection flow path formed between the piston and the back pressure chamber. And a main retainer, a disk for generating a damping force between the back pressure chamber and the main retainer, and a sub retainer for adjusting a flow path connected to the back pressure chamber.

In the conventional variable shock absorber, the spool moves according to the current input to the solenoid valve, and various damping force performance curves can be implemented in real time as the flow path is changed. However, various sensors (Wheel G-sensor, Body G-sensor) are required for vehicle behavior recognition, have complex valve flow paths, and the system is expensive.

Korean Unexamined Patent Publication No. 10-2009-0003019 (January 09, 2009, published)

The present invention provides a damping force variable shock absorber having a wide range of use because it can selectively use a soft or hard damping force as necessary.

According to an aspect of the present invention, a cylinder having an inner tube and an outer tube filled with a fluid; A housing coupled to a lower end of the piston rod located inside the inner tube and forming a connection flow path therein; A first piston valve coupled to the outside of the housing to define a compression chamber and a tension chamber; A magnet member provided inside the housing; A second piston valve provided inside the housing and positioned below the magnet member; And a plunger disposed between the magnet member and the second piston valve, the plunger moving with the magnetic force of the magnet member to open and close the connection flow path, wherein the plunger closes the connection flow path when the fluid flows into the hard mode. A damping force variable shock absorber may be provided to allow the fluid to pass through the second piston valve and to pass through the first piston valve and to open the connection flow path when moving in the soft mode.

The housing may include an upper housing coupled to an inner surface of the piston rod at an upper portion thereof, and a lower housing coupled to a lower portion of the upper housing and installed with the first piston valve.

The lower housing includes a disk-shaped fastening body fastened to the upper housing and a valve guide extending below the fastening body and fastening the first piston valve, wherein the first piston valve is the fastening body and the valve guide. It can be restrained by a nut coupled to the lower side.

One side may be further supported by the magnet member, and the other side may further include an elastic member for pressing the plunger toward the second piston valve.

The plunger may have a disc shaped plunger body; A plunger hole formed in the plunger body; A protrusion formed on an upper portion of the plunger body and configured to restrict horizontal movement of the elastic member; And a blocking part protruding downward from an edge of the plunger body and opening or closing a housing hole of the housing by raising or lowering the plunger body.

The plunger hole may be vertically penetrated to be positioned below the housing hole when the plunger descends, and may be penetrated downward to be connected to an upper end of the guide hole.

The connection flow passage passes through a housing hole provided in the housing, a plunger hole provided in the plunger, a second valve flow path provided in the second piston valve, and a guide hole provided in the housing when opened in the soft mode. It may be arranged to.

The second piston valve moves the fluid in the compression chamber to the tension chamber through the connection flow path during the compression stroke of the piston rod in the open connection flow path, and moves the fluid in the tension chamber to the compression chamber during the tension stroke of the piston rod. It may be characterized by moving.

A gap ring may be interposed between the inner tube and the first piston valve.

The second piston valve may be inserted and restrained between the stepped portion provided in the upper housing and the lower housing.

A stop ring may further be installed between the stepped portion and the second piston valve to serve as a locking step to limit a moving range of the plunger.

In the fluid movement between the compression chamber and the tension chamber, the first piston valve may be provided with a large flow resistance relative to the second piston valve.

The damping force variable shock absorber according to the present invention selects a flow path through which a fluid passes by using a plunger which is positioned in a soft or hard mode by a solenoid valve. Hard damping force can be used selectively.

It can be configured inside the cylinder, and because the variable width of the plunger is not large, it is not bulky and not complicated, which can reduce the manufacturing cost and secure design freedom.

It has a simple structure while forming two modes of damping force (soft damping force / hard damping force) to increase ride comfort and adjustment stability. In addition, since the first piston valve and the second piston valve are separately configured, they can be tuned independently, and the two-way (tensile / compression direction) can be controlled simultaneously, so that the tuning freedom is also high.

1 is a front sectional view of a damping force variable shock absorber according to an embodiment of the present invention.
Figure 2 shows an enlarged view of the solenoid valve and the piston valve of the damping force variable shock absorber according to an embodiment of the present invention.
3 is a front sectional view for showing a stroke state in a state in which the plunger is moved to the hard mode in the damping force variable shock absorber according to the present invention.
Figure 4 is a front sectional view for showing the stroke state in a state in which the plunger is moved to the soft mode in the damping force variable shock absorber according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are presented to sufficiently convey the spirit of the present invention to those skilled in the art. The present invention is not limited to the embodiments presented herein but may be embodied in other forms. The drawings may omit illustrations of parts not related to the description in order to clarify the present invention, and may be exaggerated to some extent in order to facilitate understanding.

1 is a front sectional view of a damping force variable shock absorber according to an embodiment of the present invention, Figure 2 is an enlarged view of the solenoid valve 200 and the piston valve (300, 400) of the damping force variable shock absorber.

Referring to the drawings, the damping force variable shock absorber according to an embodiment of the present invention is located in the inner tube 11, the inner tube 11, the cylinder 10 having the inner tube 11 and the outer tube 12 is filled with the fluid The housing 100, which is coupled to the lower end of the piston rod 20 and forms a connection flow path 101 therein, is coupled to the outside of the housing 100 to partition the lower compression chamber 11a and the upper tension chamber 11b. The first piston valve 300, the magnet member 210 provided inside the housing 100, the second piston valve 400 provided inside the housing 100 and positioned below the magnet member 210, the magnet member ( It is installed between the 210 and the second piston valve 400, and includes a plunger 230 to move the magnetic force of the magnet member 210 to open and close the connection flow path 101 shown in FIG.

The cylinder 10 includes an inner tube 11 forming a space therein and an outer tube 12 provided outside the inner tube 11. The inner tube 11 may have a cylindrical shape that forms a space therein, and a fluid (oil or the like) is filled in the inner tube 11. The outer tube 12 is installed to a larger diameter on the outer diameter of the inner tube 11, the outer tube 12 may have a shape corresponding to the inner tube (11). The inner tube 11 may be divided into a compression chamber 11a and a tension chamber 11b by the first piston valve 300 to be described later.

One end of the outer tube 12 and one end of the piston rod 20 can perform a compression and tension stroke in the state connected to the vehicle body side or the wheel side, respectively. In addition, a separate coupling part (not shown) for connecting to the vehicle body side or the wheel side may be installed at the lower end of the outer tube 12.

One end of the piston rod 20 is coupled to the housing 100, and the other end thereof is extended to the outside of the outer tube 12 to be connected to the vehicle body side or the wheel side of the vehicle.

The storage chamber 30 is formed at regular intervals between the outer tube 12 and the inner tube 11, and the storage chamber 30 is separated from the compression chamber 11a by the body valve 40. During the compression stroke, the fluid in the compression chamber 11a may be moved to the storage chamber 30 through the flow path of the body valve 40. On the contrary, when the piston rod 20 is tensioned, the fluid in the storage chamber 30 may be moved to the compression chamber 11a through the flow path of the body valve 40.

The body valve 40 is installed at the lower end of the compression chamber 11a to distinguish the compression chamber 11a from the storage chamber 30. At this time, the fluid moves upward or downward through the flow path of the body valve 40, the damping force is generated by the resistance in the process of moving the fluid in the tension and compression stroke direction.

Upper and lower portions of the body valve 40 are provided with disks for opening and closing the pressure passage in a selected direction. For example, when the piston rod 20 and the first piston valve 300 are compressed in a stroke (downward in the illustrated direction), the fluid moves to the storage chamber 30 through the flow path of the body valve 40. On the contrary, the piston rod 20 and the first piston valve 300 operate in the opposite direction to the above-described operation during the tension stroke (rising in the direction shown).

The housing 100 is made of a metal iron material, the upper housing 110 is coupled to the inside of the piston rod 20, the lower portion is fastened to the lower portion of the upper housing 110 and the first piston valve 300 is installed It may include a housing 120.

The upper housing 110 is connected to the piston rod 20 by a rod fastening portion 111 provided at the upper portion. The housing hole 110a communicates with the inner space along the outer circumferential surface of the upper housing 110. The housing hole 110a horizontally connects the connection flow path 101 and the tension chamber 11b and moves the fluid in the tension chamber 11b to the connection flow path 101 by the opening operation of the plunger 230.

The stepped part 112 restrains the second piston valve 400 from above and below together with the fastening body 121 of the lower housing 120. In this case, a stop ring 240 may be interposed between the stepped part 112 and the second piston valve 400. The stop ring 240 limits the movable range of the plunger 230 by serving as a locking jaw when the plunger 230 moves downward.

The lower housing 120 includes a disc-shaped fastening body 121 press-fitted under the upper housing 110, and a valve guide 122 to which the first piston valve 300 is fastened to the bottom of the fastening body 121. The first piston valve 300 may be restrained and fastened by a nut 130 coupled to the fastening body 121 and the valve guide 122.

The lower housing 120 has an upper end thereof coupled to the upper housing 110 at the bottom of the solenoid valve 200, and the inner space of the lower housing 120 is compressed through the guide hole 122a through the compression chamber 11a. ).

The guide hole 122a may be provided at right angles with the housing hole 110a in the inner side of the valve guide 122. In this case, the guide hole 122a may have a larger cross-sectional area than the first valve flow path 300a of the first piston valve 300. In addition, a second valve flow path 400a is formed to penetrate up and down between the housing hole 110a and the guide hole 122a to move the fluid in the tension chamber 11b to the compression chamber 11a.

On the other hand, the connection flow path 101 is formed in the housing 100 to communicate the compression chamber (11a) and the tension chamber (11b) through the second piston valve (400). Here, the connection flow path 101 is provided in the housing hole (110a) is provided in the upper housing 110, the plunger hole (231a) is provided in the plunger 230, the second piston valve 400 when opening The second valve flow path 400a and the guide hole 122a provided in the lower housing 120 may be passed.

The solenoid valve 200 opens and closes the connection flow path 101 by elevating the plunger 230 while being coupled to the piston rod 20 located inside the inner tube 11. To this end, the solenoid valve 200, the magnet member 210 for generating a magnetic force by electricity transmitted from the wire 211, which is a power supply means, the plunger 230 to be elevated by the magnet member 210, and one end It is provided with an elastic member 220 which is supported by the magnet member 210 and provides an elastic force to the plunger 230 to the other end.

The magnet member 210 forms a magnetic force by the power supplied from the outside to convert the variable shock absorber into a soft mode or a hard mode using the plunger 230. That is, the solenoid valve 200 is to raise or lower the plunger 230 according to the direction in which the magnetic force is generated, so that the fluid passes through either the first piston valve 300 or the second piston valve 400 The damping force can be converted.

The plunger 230 closes the connection flow path 101 when moving in the hard mode to allow the fluid to pass through the first piston valve 300, and opens the connection flow path 101 when moving in the soft mode to allow the fluid to pass through the second piston valve ( 400).

The plunger 230 is a plunger body 231 of a disc shape, a plunger hole 231a formed in the plunger body 231, a protrusion formed on the plunger body 231 and restraining horizontal movement of the elastic member 220. 232, and a blocking portion 233 protruding downward from the edge of the plunger body 231 and opening and closing the housing hole 110a of the housing 100 by raising or lowering the plunger body 231. have.

The blocking unit 233 may close the housing hole 110a when the plunger body 231 is raised, and open the housing hole 110a when the plunger body 231 is lowered. On the contrary, unlike shown, the blocking part 233 may be provided to open the housing hole 110a when the plunger body 231 is raised, and close the housing hole 110a when the plunger body 231 is lowered. It is not limited to this.

Meanwhile, the plunger hole 231a is vertically penetrated to be positioned below the housing hole 110a when the plunger 230 descends, and penetrates downward to form the second valve flow path 400a and the guide hole 122a. can do.

The first piston valve 300 divides the inside of the inner tube 11 into the compression chamber 11a and the tension chamber 11b, and the first piston valve 300 reciprocates in the inside of the inner tube 11. While generating damping force by the resistance of the fluid. For example, when the 1st piston valve 300 performs a compression stroke, the pressure of the lower compression chamber 11a raises compared with the upper tension chamber 11b. At this time, the fluid filled in the compression chamber 11a moves to the tension chamber 11b while pushing the valve means through the first valve flow path 300a. In this process, a damping force is generated by the resistance of the fluid. On the contrary, in the case where the first piston valve 300 performs a tension stroke, the first piston valve 300 operates in the reverse direction to the compression stroke process.

The gap ring 310 may be interposed between the inner tube 11 and the first piston valve 300. The gap ring 310 is made of a plastic material to prevent damage or deformation caused by the direct contact between the inner tube 11 and the first piston valve 300 each made of a metal material.

The second piston valve 400 communicates the compression chamber 11a and the tension chamber 11b through the second valve flow path 400a. In this case, in the fluid movement between the compression chamber 11a and the tension chamber 11b, the second piston valve 400 may generate less flow resistance than the first piston valve 300. The second piston valve 400 may be inserted and restrained between the stepped portion 112 and the lower housing 120 provided in the upper housing 110. In this case, a stop ring 240 may be interposed between the stepped part 112 and the second piston valve 400.

The second piston valve 400 moves the fluid in the compression chamber 11a to the tension chamber 11b through the connection channel 101 during the compression stroke of the piston rod 20 in the connection channel 101 open state, and the piston The fluid in the tension chamber 11b may be moved to the compression chamber 11a during the tension stroke of the rod 20.

Figure 3 is a front sectional view for showing the stroke state in a state in which the plunger is moved to the hard mode in the damping force variable shock absorber according to the present invention, Figure 4 is a plunger in the damping force variable shock absorber according to the present invention Is a front sectional view for showing a stroke state in a state in which the soft mode is moved. Hereinafter, the operation of the damping force variable shock absorber will be described with reference to FIG. 3 or 4.

In the compression stroke of the piston rod 20 in the state where the plunger 230 is raised by the solenoid valve 200, the fluid of the compression chamber 11a flows into the first valve flow path 300a of the first piston valve 300. That is, it is moved to the tension chamber 11b through the main flow path. At this time, the fluid moving to the tension chamber 11b through the first piston valve 300 generates a hard damping force.

On the contrary, in the tension stroke of the piston rod 20 in the state where the plunger 230 is raised by the solenoid valve 200, the fluid of the tension chamber 11b is compressed through the main flow path of the first piston valve 300. The hard damping force is generated while moving to the chamber 11a.

On the other hand, during the compression stroke of the piston rod 20 in the state where the plunger 230 is lowered, the fluid of the compression chamber 11a flows into the guide hole 122a. At this time, the fluid moved to the connection flow path 101 through the guide hole 122a is moved to the tension chamber 11b through the housing hole 110a via the second valve flow path 400a of the second piston valve 400. While generating a soft damping force.

On the contrary, in the tension stroke of the piston rod 20 in the state where the plunger 230 is lowered by the solenoid valve 200, the fluid of the tension chamber 11b flows in the second valve flow path of the second piston valve 400 ( Moving to the compression chamber 11a through 400a generates a soft damping force.

Accordingly, in the damping force variable shock absorber according to the exemplary embodiment of the present invention, the second piston valve 400 (Soft Valve) is located in the housing 100, and the first piston valve 300 (Hard) is located outside the housing 100. Valve) is located, the plunger 230 is located in the housing 100, the plunger 230 can move up and down according to the current input to the solenoid valve 200 to open and close the housing hole (110a). have.

When the plunger 230 moves upward to block the housing hole 110a, oil flows only into the first piston valve 300 while blocking the flow path flowing into the connection flow path 101 to cause hard damping force. On the contrary, when the plunger 230 moves downward to open the housing hole 110a, oil flows into the connection flow path 101, and the introduced oil moves through the second piston valve 400 to provide soft damping force. cause.

Therefore, by forming two modes of damping force (Soft damping force / Hard damping force), it is possible to increase the ride comfort and adjustment stability compared to the existing, and has a simple structure. In addition, since the first piston valve 300 and the second piston valve 400 are configured separately, they can be tuned independently, and they can control both directions (tensile / compression direction) at the same time, so that the tuning freedom is high.

Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, this is merely exemplary, and those skilled in the art may realize various modifications and other equivalent embodiments therefrom. I can understand. Therefore, the true scope of the invention should be defined only by the appended claims.

10: cylinder 11: inner tube
11a: compression chamber 11b: tension chamber
12: outer tube 20: piston rod
30: storage chamber 40: body valve
100: housing 101: connection flow path
110: upper housing 111: rod fastening portion
110a: housing hole 112: stepped portion
120: lower housing 121: fastening body
122: valve guide 122a: guide hole
130: nut 200: solenoid valve
210: magnet member 211: wire
220: elastic member 230: plunger
231: plunger body 232: protrusion
231a: plunger hole 233: blocking part
240: stop ring 300: first piston valve
300a: first valve flow path 310: gap ring
400: second piston valve 400a: second valve flow path

Claims (12)

A cylinder having an inner tube and an outer tube filled with a fluid;
A housing coupled to a lower end of the piston rod located inside the inner tube and forming a connection flow path therein;
A first piston valve coupled to the outside of the housing to define a compression chamber and a tension chamber;
A magnet member provided inside the housing;
A second piston valve provided inside the housing and positioned below the magnet member; And
And a plunger disposed between the magnet member and the second piston valve, the plunger moving by the magnetic force of the magnet member to open and close the connection flow path.
The plunger closes the connecting passage when moving in the hard mode to allow fluid to pass through the first piston valve, and the plunger is variable in damping force to open the connecting passage when moving in the soft mode to allow the fluid to pass through the second piston valve. Absorber. The method of claim 1,
The housing is
An upper housing coupled to an inner surface of the piston rod at an upper portion thereof;
Damping force variable shock absorber comprising a lower housing coupled to the lower portion of the upper housing and the first piston valve is installed. The method of claim 2,
The lower housing includes a disk-shaped fastening body fastened to the upper housing and a valve guide extending below the fastening body and fastening the first piston valve.
The first piston valve is a damping force variable shock absorber is restrained by a nut coupled to the fastening body and the valve guide lower side. The method of claim 1,
One side is supported by the magnet member, the other side is a damping force variable shock absorber further comprises an elastic member for pressing the plunger toward the second piston valve. The method of claim 4, wherein
The plunger is
Disc-shaped plunger body;
A plunger hole formed in the plunger body;
A protrusion formed on an upper portion of the plunger body and configured to restrict horizontal movement of the elastic member; And
And a blocking portion protruding downward from an edge of the plunger body and opening and closing the housing hole of the housing by raising or lowering the plunger body. The method of claim 5,
The plunger hole
The damping force variable shock absorber, characterized in that it is formed vertically penetrating is located below the housing hole when the plunger is lowered, and is connected to the upper end of the guide hole through the lower portion. The method of claim 1,
The connection flow path includes a housing hole provided with a fluid in the housing, a plunger hole provided in the plunger, a second valve flow path provided in the second piston valve, and a guide hole provided in the housing. Damping force variable shock absorber is provided to pass through. The method of claim 1,
The second piston valve
The fluid of the compression chamber in the compression stroke of the piston rod in the open connection channel flow state to the tension chamber through the connection flow path, characterized in that for moving the fluid of the tension chamber to the compression chamber during the tension stroke of the piston rod Damping force variable shock absorber. The method of claim 1,
A damping force variable shock absorber having a gap ring interposed between the inner tube and the first piston valve. The method of claim 1,
The second piston valve is a variable shock absorber is sandwiched between the stepped portion provided in the upper housing and the lower housing. The method of claim 10,
A variable shock absorber is further provided between the stepped portion and the second piston valve, the stop ring serving as a locking step to limit the moving range of the plunger. The method of claim 1,
In the fluid movement between the compression chamber and the tension chamber, the first piston valve is a variable shock absorber is provided with a larger flow resistance than the second piston valve.

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