JPH0538434U - Cushion structure in position-dependent shock absorber - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Not only can an effective cushioning effect be expected, but reliability in durability can be obtained, and the number of parts can be reduced to reduce the number of assembly steps. (EN) Provided is a cushion structure of a position-dependent shock absorber, which is optimal for reducing the cost and lowering the cost and expecting to improve its versatility. An annular spring bearing 6 that carries the lower end of a suspension spring 5 that is compressed when the piston rod 2 is retracted into the cylinder 1 is provided with a push rod 30 that projects from the upper end of the damping force generation unit 3. In the position-dependent shock absorber formed so as to be capable of changing the damping force generated by the damping force generating portion 3 by pushing it into the lower end surface of the annular spring bearing 6 and the outer periphery of the bottom portion side of the cylinder 1. Forming annular support 1
An annular cushion member 9 made of a rubber material is disposed between the upper end surface of a and the annular cushion member 9 is formed to have a space 9a in which the push rod 30 is present.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention relates to a cushion structure of a position-dependent shock absorber formed so as to change the damping force generated in the damping force generating portion arranged outside the cylinder depending on the position of the shock absorber main body during compression operation. Regarding improvement.

[0002]

[Prior Art]

 As a position-dependent shock absorber formed so as to change the damping force generated in the damping force generating portion arranged outside the cylinder depending on the position of the shock absorber main body during compression operation, as shown in FIG. A structure having a structure as shown in is proposed.

That is, in this position-dependent shock absorber as a conventional example, when the piston rod 2 is retracted into the cylinder 1, the working oil in the oil chamber R in the cylinder 1 generates a damping force disposed outside the cylinder 1. The annular spring bearing 6 is formed so as to flow into the accumulator 4 via the portion 3 and bears the lower end of the suspension spring 5 which is compressed when the piston rod 2 is retracted into the cylinder 1. The push rod 30 projecting from the upper end of the force generating portion 3 is pushed into the damping force generating portion 3 so as to change the damping force generated by the damping force generating portion 3.

A disc spring 7 is arranged between the annular spring receiver 6 and an annular support portion 1a formed on the outer periphery of the bottom side of the cylinder 1, and the suspension spring 5 has a large size. When the disc spring 7 is compressed, the spring receiver 6 pushes down the push rod 30 via the nut 31 screwed to the push rod 30, and the inside of the damping force generating portion 3 is depressed. The damping force generated by the damping force generating unit 3 is adjusted to an upward tendency by pushing in.

Therefore, according to the position-dependent shock absorber according to the conventional proposal, an extremely large damping force is generated by the damping force generating portion 3 during a large compression operation of the shock absorber body, and the bottom of the piston rod 2 is projected. Can be effectively prevented in advance.

[0006]

[Problems to be solved by the device]

 However, the position-dependent shock absorber as the conventional example has the following disadvantages.

That is, in the cushion structure in the position-dependent shock absorber as the conventional example described above, since the disc spring 7 is used as a so-called cushion member, the disc spring 7 sandwiches the dust and the effect thereof is obtained. There is a danger that it will not be possible to expect proper operation, and if the plate 7 is made of an iron material, there is the disadvantage that durability against rust cannot be expected.

Further, when the disc spring 7 is made of iron material, the cylinder 1 that constitutes the shock absorber body is made of aluminum material as in recent years, and the disc spring 7 is used to make the cylinder 1 There is a danger that the outer circumference of the product will be worn, and its use is not preferable.

When the disc spring 7 made of an iron material is used even if the cylinder 1 is made of an aluminum material, it is necessary to interpose a spring seat 8 on the outer periphery of the cylinder 1 as shown in the figure. However, there is a problem that the number of parts increases.

On the other hand, when the disc spring 7 sandwiches the dust, the dust is also attached to the outer periphery of the push rod 30 protruding from the upper end of the damping force generating portion 3, so that the push rod 30 is internally attached. There is a risk that the dust may impede the slidability of the push rod 30 when it is pushed into, or may enter the damping force generating portion 3 and hinder the smooth operation of the damping force generating portion 3.

As a result, in the conventional cushion structure using the disc spring 7, there is a fear that an effective cushioning effect cannot be expected, durability cannot be obtained, and the number of members increases. As a result, the number of assembling steps will increase and it will not be possible to reduce the cost.

The present invention was devised in view of the above-mentioned circumstances, and the purpose thereof is not only to expect an effective cushioning effect, but also to have reliability in durability. In addition, it is possible to reduce the number of members, reduce the number of assembly steps, and reduce the cost, and it is ideal for position-dependent shock absorbers that are expected to improve their versatility. The purpose is to provide a cushion structure.

[0013]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the structure of the present invention is adopted, in which the working oil in the oil chamber in the cylinder flows into the accumulator through the damping force generating portion arranged outside the cylinder when the piston rod is retracted into the cylinder. And an annular spring bearing that carries the lower end of the suspension spring that is compressed when the piston rod is retracted into the cylinder. In a position-dependent shock absorber formed so as to be able to change the damping force generated by the damping force generating portion by pushing it into the generating portion, it is formed on the lower end face of the annular spring bearing and the outer periphery on the bottom side of the cylinder. An annular cushion member made of a rubber material is provided between the annular support member and the upper end surface of the annular support member, and the annular cushion member allows the push rod to be present therein. It is an formed comprising to have.

[0014]

[Action]

 Therefore, the cushion member itself can have a sufficient anticorrosion function, and the durability of the cushion structure is improved.

The cushion member itself does not have a fear of catching dust, and it becomes possible to prevent the dust from adhering to the outer periphery of the push rod existing inside the cushion member. The smooth operation of the generator is guaranteed.

Further, even if the cushion member is slidably contacted with the outer circumference of the cylinder, the outer circumference of the cylinder is not worn.

[0017]

【Example】

 As will be described below with reference to the drawings, as shown in FIG. 1, the position-dependent shock absorber according to one embodiment of the present invention is similar to the conventional example when the piston rod 2 is immersed in the cylinder 1. The hydraulic oil in the oil chamber R in the cylinder 1 is formed so as to flow into the accumulator 4 via the damping force generating portion 3 arranged outside the cylinder 1, and the piston rod 2 is immersed in the cylinder 1. An annular spring bearing 6 that bears the lower end of the suspension spring 5 that is compressed at some time pushes the push rod 30 protruding from the upper end of the damping force generating unit 3 into the damping force generating unit 3 and the damping force generating unit 3 It is formed so that the damping force generated at can be changed.

However, in the cushion structure of the shock absorber, an annular cushion member 9 made of a rubber material is provided between the annular spring receiver 6 and the annular support portion 1a formed on the outer periphery of the bottom side of the cylinder 1. As shown in FIG. 2, the annular cushion member 9 is formed so as to have a space 9a in which the push rod 30 is present.

When the suspension rod 5 is largely compressed by the piston rod 2 being largely retracted into the cylinder 1, and the cushion member 9 is compressed, the spring bearing 6 pushes the push rod 30 downward. It is said that the damping force generated in the damping force generating section 3 can be adjusted to an upward tendency by pushing it into the damping force generating section 3.

Incidentally, the damping force generating portion 3 is housed in a housing portion 1b extending to the bottom portion of the cylinder 1, and the accumulator 4 is structured so as to be connected to the housing portion 1b. ..

In the present embodiment, the cushion member 9 has an upper spring surface 6 to which an upper spring bearing 6 is continuously provided by baking or the like, and a lower end surface of the cushion member 9 above the supporting portion 1a formed on the cylinder 1. The annular sheet members 10 arranged on the end faces are continuously provided by baking or the like.

The annular seat member 10 and the spring receiver 6 are both set so as to be mounted on the outer periphery of the cylinder 1 without rattling.

In the present embodiment, the cushion member 9 has its inner peripheral surface adjacent to the outer peripheral surface of the cylinder 1, but it is assumed that an appropriate gap is formed between them. May be.

Further, the cushion member 9 in this embodiment is formed as a so-called solid type, but instead of this, the cushion member 9 is formed so as to have a hollow portion and the like, and has an elastic characteristic. It may be changed.

By the way, the space 9a in the cushion member 9 is set so as to allow the push rod 30 protruding from the upper end of the damping force generating unit 3 to be present therein, but the peripheral wall 9b constituting the space 9a is formed. (Refer to the broken line diagram in FIG. 2) functions not only as a so-called spring but also as a cover that prevents dust from entering the space 9a.

Therefore, in the annular seat member 10, a cutout hole 10a (see the broken line diagram in FIG. 3) is formed so as to fit in the space 9a in the cushion member 9. ..

The guide portion 3b formed on the upper end surface of the casing 3a constituting the damping force generating portion 3 is projected in a so-called liquid-tight state in the cutout hole 10a and the space portion 9a (see FIG. (See FIG. 3).

Incidentally, the damping force generating section 3 is configured as follows in this embodiment.

That is, as shown in FIG. 3, the damping force generating portion 3 includes a housing portion 1 b extending to the bottom portion of the cylinder 1 and a housing portion 4 b extending to the main body 4 a of the accumulator 4. In addition, a casing 3a fixed in a liquid-tight state to one end side which is the upper end of the housing and a cap 3c which is screwed in a liquid-tight state to the other end side which is the lower end in the figure have a predetermined shape. A chamber is formed.

The above-mentioned chamber communicates with the oil chamber R in the cylinder 1 through the port 1c for opening the cylinder 1 and the oil in the accumulator 4 through the port 4c for opening the accumulator 4 is provided. It is configured to communicate with the chamber 4d.

In the present embodiment, the casing 3a is configured such that the lower end side thereof is formed in a tubular shape and the necessary members are housed inside the tubular portion. A communication hole 3d penetrating this is opened to enable communication between the outer peripheral side and the inner peripheral side of the tubular portion.

Further, the accumulator 4 has a bellows 40 which is a diaphragm inside, and defines a gas chamber 4d.

The damping force generating portion 3 is provided when the push rod 30 whose upper end is in contact with the spring receiver 6 and the working oil from the oil chamber R in the cylinder 1 flows toward the accumulator 4. A damping valve 32 that operates, a valve seat member 33 that slidably interposes the damping valve 32 and forms a bypass path that bypasses the damping valve 32, and the damping valve 32 is seated on the valve seat member 33. As described above, the biasing spring 34, the needle body 35 whose base end is connected to the base end of the biasing spring 34 and the tip of the push rod 30, and the operation in the bypass passage. And a poppet 36 for controlling the oil flow rate.

To explain briefly, the push rod 30 slidably penetrates the shaft core of the casing 3a in a liquid-tight state in the axial direction which is the vertical direction in the drawing, and is formed at the lower end thereof. The flange portion 30a is formed so as to be present inside the chamber inside the casing 3a.

It should be noted that the flange portion 30a prevents the push rod 30 from so-called slipping out to the outside and, in this embodiment, constitutes a connecting portion to a needle body 35 described later. It is set.

In this embodiment, the damping valve 32 is formed in the shape of an annular slide valve, and is arranged on the outer periphery of a valve seat member 33, which will be described later, in the vertical direction in the figure. It is interposed so as to be slidable in the axial direction of 33.

Then, when hydraulic pressure acts on the pressure receiving surface, it retreats in the upward direction in the figure against the urging force of the urging spring 34, and the outer peripheral side of the annular check valve 37 is opposed to this. It is set so as to allow the working oil to flow through the gap formed between the inner circumference side and the inner circumference side.

The rear end of the biasing spring 34, which is the upper end in the figure, is locked by a panel receiver 34a adjacent thereto.

The valve seat member 33 has an annular valve case 3e, which is sandwiched between the casing 3a and the cap 3c, and has its lower end side disposed on the inner peripheral side. A cylindrical portion 33a that stands up on the axial center of the chamber to form a bypass path and slidably mounts the damping valve 32 on the outer periphery thereof, and the inside of the cylinder 1 through the communication holes 1c and 4c. And a seat portion 33b which is arranged so as to cut off the communication between the oil chamber R and the oil chamber 4d in the accumulator 4 to make the damping valve 32 a seat and a seat, and which accommodates the check valve 37 and the non-return spring 37a. , Are formed.

The tubular portion 33a has a through hole 33c for allowing a needle body 35, which will be described later, to be inserted in the shaft core portion thereof, and the tubular portion 33a penetrates through the wall thickness of the tubular portion 33a. It has a through hole 33c that is opened and a lateral hole 33d that allows communication with the outer peripheral side of the cylindrical portion 33a, that is, the chamber.

The through hole 33c is formed so as to have an inner diameter that matches the outer diameter of the needle body 35. Therefore, the tip of the needle body 35 is present in the through hole 33c. During this time, the pointed portion is in a so-called plug state, and the through hole 33c and the outer peripheral side of the cylindrical portion 33a can be communicated with each other only through the lateral hole 33d.

The lower end of the tubular portion 33a is open to the lower surface side of a seat portion 33b described later.

The seat portion 33b has a port 33e opened in its thick portion so that the upper end surface side and the lower end surface side can communicate with each other, and the lower end thereof has an outer peripheral side thereof. And a leg portion 33g having a notch 33f that enables communication with the lower end surface side, and the lower end of the through hole 33c of the cylindrical portion 33a is opened on the lower surface of the shaft core portion. It is composed.

Therefore, the hydraulic oil from the oil chamber R in the cylinder 1 flows into the chamber through the notch 33f and the port 33e and through the through hole 33c and the lateral hole 33d communicating with the through hole 33c. Will be done.

The damping valve 32 is arranged so as to face the port 33e.

The needle body 35 can adjust the amount of oil passing through the bypass passage by opening and closing the lateral hole 33d opened in the tubular portion 33a when the needle body 35 appears in and out of the tubular portion 33a. It is formed.

The needle body 35 has a flange portion 35a at its rear end, and the flange portion 35a is adjacent to the flange portion 30a at the lower end of the push rod 30.

Further, the needle body 35 is configured such that the rear end thereof penetrates the shaft core portion of the spring receiver 34a, and the flange portion 35a is positioned on the so-called rear side of the spring receiver 34a. It has a structure that prevents this from falling off.

Therefore, in this embodiment, the needle body 35 is connected to the spring receiver 34a and to the push rod 30 by the urging force from the urging spring 34 acting on the spring receiver 34a. That is, the structure is separated in advance.

As a result, the needle body 35 is irrespective of how the push rod 30 is arranged, that is, even if the push rod 30 is arranged at a predetermined position in an eccentric state, its tip end Since the portion is inserted into the tubular portion 33a in advance, even if the push rod 30 is eccentric, it operates as set without being affected by the eccentricity, that is, it appears and disappears from the tubular portion. Can be realized smoothly.

The poppet 36 is screwed to the shaft core portion of the cap 3c so that its sharp end faces the lower end opening of the through hole 33c of the tubular portion 33a. The lower end surface of the cap 3c is connected to a plug 36a which is press-fitted into the cap 3c at the shaft core portion. When the plug 36a is rotated by using an appropriate tool or the like, the poppet 36 The pointed end is configured to open and close the lower end opening of the through hole 38c.

Therefore, according to the damping force generator 3, the hydraulic oil flowing from the oil chamber R in the cylinder 1 flows into the accumulator 4 via the damping valve 32 during the compression operation of the shock absorber body. In addition, the hydraulic oil from the accumulator 4 can flow into the oil chamber R in the cylinder 1 through the check valve 36 when the shock absorber main body is extended. When the hydraulic oil passes through 32, a predetermined compression side damping force is generated.

When the suspension spring 5 is largely bent and the spring receiver 6 is lowered due to a large compression operation of the shock absorber main body, the push rod 30 is lowered by the lowering of the spring receiver 6, and at this time, the damping valve The urging spring 34 urging 32 is compressed to increase the initial load on the damping valve 32, and thereafter, the damping force generated by the damping valve 32 is increased.

On the other hand, at this time, it is a condition that the poppet 36 opens the lower end opening of the cylindrical portion 33a to open the bypass path. The needle body 35 previously inserted into the tubular portion 33a is deeply immersed in the tubular portion 35a, and at this time, the lateral hole 33d opened in the tubular portion 35a is It tends to be closed, and the amount of hydraulic oil passing through the through hole 33 c forming the bypass passage is reduced.

As a result, it is possible to prevent the link from which the amount of oil passing through the damping valve 32 is increased and the damping force generated thereafter is large and the bottoming of the piston rod 2 due to the large compression operation of the shock absorber. It will be possible.

In the cushion structure of the position-dependent shock absorber according to this embodiment formed as described above, the suspension spring 5 largely flexes and the spring receiver 6 descends due to a large compression operation of the shock absorber body. Then, the cushion member 9 also bends, and at this time, a predetermined cushion effect is exerted.

Since the cushion member 9 is made of a rubber material, the cushion member 9 itself has a rust preventive function, and therefore the rust resistance of the cushion structure can be easily improved.

Further, since the cushion member 9 in the present invention does not have an outward multi-stage gap like the disc spring, there is no danger of dust being trapped inside the cushion member 9 and the cushion structure operates smoothly. Will be possible.

Furthermore, since the cushion member 9 is configured to cover the push rod 30 together with the spring receiver 6, it is possible to prevent dust from adhering to the outer periphery of the push rod 30.

[0060]

[Effect of the device]

 As described above, according to the present invention, it is possible to expect an effective cushioning effect because it does not cause inconvenience such as dust entrapment at the time of its use, and it is also possible that the cushion member is made of a rubber material, so that rusting There is no danger of deterioration of durability, reliability of durability can be obtained, and further, it is possible to prevent dust from adhering to the outer periphery of the push rod and expect smooth operation of the damping force generating part as set. Since the arrangement of the spring seat can be omitted, the number of members can be reduced, the number of assembling steps can be reduced, and the cost can be reduced, which is the most suitable for expecting the improvement of its versatility. There is a point.

[Brief description of drawings]

FIG. 1 is a partial side view showing a partially broken view of a position-dependent shock absorber according to an embodiment of the present invention.

FIG. 2 is an upper end view showing a cushion member.

FIG. 3 is a partial cross-sectional view showing an enlarged main part of the present invention.

FIG. 4 is a partial side view showing a position-dependent shock absorber as a conventional example, partially broken away.

[Explanation of symbols]

 1 Cylinder 1a Support part 2 Piston rod 3 Damping force generation part 4 Accumulator 5 Suspension spring 6 Spring receiver 9 Cushion member 9a Space part 30 Push rod R Oil chamber

Claims (1)

[Scope of utility model registration request] 1. When the piston rod is retracted into the cylinder, the working oil in the oil chamber in the cylinder is formed so as to flow into the accumulator through a damping force generating portion disposed outside the cylinder, and the piston is An annular spring bearing, which carries the lower end of a suspension spring that is compressed when the rod is retracted into the cylinder, pushes a push rod protruding from the upper end of the damping force generating section into the damping force generating section and generates it in the damping force generating section. In a position-dependent shock absorber formed so as to be able to change the damping force that is applied, between the lower end surface of the annular spring bearing and the upper end surface of the annular support portion formed on the outer periphery on the bottom side of the cylinder. An annular cushion member made of a rubber material is disposed, and the annular cushion member is formed to have a space portion in which the push rod is present. Cushion structure for position-dependent shock absorber.