JPS6188035A - Hydraulic damper of variable damping force type - Google Patents

Abstract

PURPOSE:To enable damping force of being varied in accordance with stroke by disposing a spring between a cylinder and a damping force generating valve which is disposed on the lower face of a piston. CONSTITUTION:A tightening member consisting of a nut 5 is made in close contact with the end, at the side of a piston 4, of a piston rod 3. A valve guide 8 is engaged on the external face of the member as the guide can be slided thereon. The valve guide 8 presses the external part of a damping force generating check valve 7, which is disposed on the lower face of the piston 4, in the closing direction of the valve 7. Springs 11 and 12 are disposed between a valve guide 8 and a cylinder 2 so that a force which closes the check valve 7 may be varied in accordance with stroke.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a variable damping force type hydraulic damper.

(Prior Art) For example, in a motorcycle damper, etc., the damping force on the rebound side gradually decreases as the extension stroke increases, that is, as the fully extended state approaches, that is, the damping force changes depending on the stroke. It is desirable to do so.

(Problems to be Solved by the Invention) Various position-dependent damping force hydraulic dampers of this type have been proposed, but they have complex structures and lack operational stability.

SUMMARY OF THE INVENTION Therefore, the present invention provides a variable damping force hydraulic damper which has a simple structure and high operational stability.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a check mark provided on the piston on the outer periphery of the fastening material bound to the piston side end of the piston rod inserted into the cylinder. The hydraulic damper of the present invention was constructed by slidably fitting a valve guide that presses the outer circumference of the valve toward the closing side, and interposing a spring between the traction guide and the cylinder.

(Function) As the extension stroke increases, the pressing force of the spring that biases the check valve toward the closing side weakens, and the flow resistance of oil passing through the check valve decreases, causing damping that occurs based on this flow resistance. Power also decreases.

(Example) An example of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a partially cutaway side view of a variable damping force type hydraulic damper according to the present invention, and FIG. 2 is an enlarged detailed view of the portion (A) in FIG.

In the hydraulic damper (1) shown in Fig. 1, (2) is a cylinder, and inside this is a piston rod (
3) is inserted, and a piston (4) that fits into the inner circumference of the cylinder (2) so as to be able to slide vertically is connected to the F end of the piston rod (3) with a nut (5). . A plurality of oil holes (6)... are bored in the piston (4), and a check valve (7) to open and close the oil holes (8)... is provided on the bottom surface of the piston (0). In addition, the piston (
4) is formed with notches (4a) that keep some of the oil holes (8) open at all times. By the way, a valve guide (8) is fitted to the outer periphery of the nut (5) so as to be able to slide vertically, and a spring seat (8) bound to the inner lower part of the cylinder (2) is connected to the valve guide (8). )
Two springs (11) and (12) are interposed vertically in series between them with a separator (lO) interposed therebetween. Therefore.

The valve guide (8) receives the elastic force of the springs (11) and (12) and opens the check valve (7) as shown in Fig. 2.
The outer periphery of is pressed toward the closed side.

On the other hand, the piston rod (
3) An oil seal (13) and a rod guide (14) that slide on the outer periphery are fitted. Also, the piston rod (
A cushion spring (17) is stretched between the spring seats (15) and (18) provided on the upper part of the cylinder (3) and the lower outer periphery of the cylinder (2).

Therefore, inside the cylinder (2), the oil chamber (S
t), (S2), and these oil chambers (Sl), (
Hydraulic oil is sealed in S2).

Next, the action of this hydraulic damper (1) will be explained.

At the beginning of the extension stroke, the piston (4) moves toward the cylinder (
2), both springs (11),
(12) is compressed and has a high spring load, and the check valve (7) is pressed with a strong force by the valve guide (8). Therefore, at the beginning of this extension stroke, the flow resistance of the oil flowing by pushing open the check valve (7) is high, and the damping force generated based on this flow resistance also exhibits a high value.

Then, the extension stroke progresses, and the piston (4) moves into the cylinder (
2) When the inside is gradually moved upward, both springs (11), (
12) expands, and the pressing force of the valve guide (8) based on these gradually decreases, so that the damping force decreases as the extension stroke increases.

In the above, the damping force variable mechanism that changes the damping force depending on the extension stroke includes a valve guide (8) that presses the check valve (7), a spring (11) that biases the valve guide (8), ( 12) etc., the structure is simple, so there is no problem with operational stability, and the variable damping function of the hydraulic damper (1) is extremely stable.

(Effects of the Invention) As is clear from the above explanation, according to the present invention, the structure ? A variable hydraulic damper that is pure and has high operational stability can be obtained.

As mentioned above, the damping force generated by a hydraulic damper changes depending on the stroke, but since the set load of the spring that biases the check valve toward the closing side cannot be changed, the absolute damping force generated by the same hydraulic damper at each stroke The value could not be changed.

Therefore, the object of the second invention is to provide a variable damping force hydraulic damper that can change the damping force depending on the stroke and at the same time change the absolute value of the damping force itself at each stroke. It is on offer.

(Means for Solving the Problems) In order to achieve the above object, the present invention has a movable spring seat that receives a spring that biases a spring guide.

(Function) Therefore, if the spring seat is moved, the distance between the spring guide and the spring seat will change, and the load on the spring interposed between them will change, resulting in a pressing force on the check valve. is changed, and the absolute value of the damping force is arbitrarily adjusted.

(Example) An example of the second invention will be described below based on FIG. 3.

FIG. 3 shows a piston rod (103) inserted into the cylinder (102) of the hydraulic damper (101) according to the second invention from above.
) is inserted, and a piston (104) that fits into the inner periphery of the cylinder (102) so as to be vertically slidable is connected to the lower end of the piston rod (103) with a nut (105). Piston (100 has multiple oil holes (IH)
... is drilled in the lower surface of the piston (104), and a check valve (107) to be opened and closed is provided with an oil hole (10B)...
) is provided. By the way, the aforementioned Natsu (105)
A valve guide (108) is fitted to the outer periphery of the cylinder (108) so as to be slidable up and down.
102) Spring seat (109) supported at the inner lower part
), two springs (111) and (112) are interposed vertically in series with a separator (110) in between. In addition, in Fig. 3, (115).

(11B) is a spring seat, (11?) is a cushion spring, and (122) is a sub-tank.

On the other hand, a guide member (119) is inserted into and held in a lower metal (118) tied to the lower end of the cylinder (102), and an adjuster (120) is rotatably inserted into the guide member (119). It is fitted. Further, an adjustment rod (121) is screwed into the guide member (119) so as to be movable up and down, and the spring seat (109) is tied to the upper end of the adjustment rod (121).
a) is engaged with the retaining groove of the adjuster (120) so as to rotate together.

Similarly to the hydraulic damper (1) shown in FIG. 1, the damping force of this hydraulic damper (101) also changes depending on the stroke.

However, in this hydraulic damper (101), when the adjuster (120) is rotated, the adjustment rod (121) that engages with the adjuster (120) also rotates as one body and moves up and down. For example, by moving the adjustment rod (121) upward, the distance between the spring seat (109) and the valve guide (108), which are connected to the adjustment rod (121), is shortened, and the spring (111), ( 112) is compressed to increase its set load, and the valve guide (10B) presses the check valve (107) toward the closing side with a stronger force. As a result, the flow resistance of oil passing through the check valve (107) increases, and the damping force is adjusted to be high. Conversely, if the adjustment rod (121) is moved downward, the damping force is adjusted to a lower value based on the opposite theory to the above.

(Effect of :5) As is clear from the above explanation, according to the present invention, the damping force can be changed depending on the stroke, and at the same time, the absolute value of the g-damping force itself at each stroke can also be changed. be able to.

[Brief explanation of drawings]

FIG. 1 is a cutaway side view of the hydraulic damper according to the first invention, FIG. 2 is an enlarged detailed view of the part (A) in FIG. 1, and FIG. 3 is a partially cutaway side view of the hydraulic damper according to the second invention. be. In one drawing, (1) and (101) are variable damping force hydraulic dampers, (2) and (102) are cylinders, and (3) and (
103) is a piston rod, (4) and (104) are pistons, and (5). (105) is a nut, (7) and (107) are check valves, (8) and (10B) are valve guides, (θ),
(109) is a spring seat, (10), (110)
are separators, (11), (12), (111), (1
12) is a spring, (120) is an adjuster, (12)
1) is an adjustment rod.

Claims (2)

[Claims] (1) A piston rod is inserted into the cylinder, and a piston is connected to one end of the piston rod, which fits into the inner circumference of the cylinder so as to be able to slide up and down, and is equipped with a check valve that opens and closes an oil hole provided in the piston rod. A hydraulic damper configured by attaching a valve guide that presses an outer circumferential portion of the check valve toward a closing side to the outer circumference of a fastening material bonded to the piston-side end of the piston rod. A variable damping force type hydraulic damper, characterized in that a spring is interposed between the valve guide and the cylinder. (2) A piston rod is inserted into the cylinder, and a piston is connected to one end of the piston rod, which fits into the inner circumference of the cylinder so as to be able to slide up and down, and is equipped with a check valve that opens and closes an oil hole provided in the piston rod. The hydraulic damper is configured by attaching a valve guide that presses an outer circumferential portion of the check valve toward a closing side to the outer circumference of a fastening material bonded to the piston-side end of the piston rod. A variable damping force type hydraulic damper, characterized in that a spring seat is fitted in the cylinder and is movable relative to the cylinder, and a spring is interposed between the spring seat and the valve guide.