JPS635282B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a strut-type suspension system for a vehicle.

A strut-type suspension system is usually installed between the front axle of a vehicle and the vehicle body. As is well known, the main elements of a strut-type suspension system are a shock absorbing section mainly consisting of a cylinder and a piston, and a spring inserted between the vehicle body connection section and the cylinder to cushion the impact from the road surface. The cylinder side is connected to the axle side, the piston rod is connected to the vehicle body side, and the ends of the spring are engaged with the piston rod and cylinder, respectively.

One of the problems with vehicles is that when the steering wheel is turned tightly, the outside of the turn sinks and the inside of the turn rises, and when steering sharply or driving at high speeds, the vehicle may fall sideways. This is because the movement of the vehicle load toward the outside of the bend due to centrifugal force causes the outer suspension system to sink, the inner suspension system to stretch, and centrifugal force acts on the entire vehicle.

SUMMARY OF THE INVENTION An object of the present invention is to provide a strut-type suspension system that reduces vehicle lean when turning the steering wheel.

In order to achieve the above object, in the present invention,
A grooved circular hole with one end closed is formed in the piston and the piston rod, and a rod body with a circular cross section is inserted into this hole, and has a fluid passage with one end opening into the inner space of the cylinder and the other end opening on the side surface. Installed so that it can slide freely,
This rod is fixed to the cylinder. By doing this, when one opening of the fluid passage is facing the grooved circular hole (vehicle is traveling straight), the grooved circular hole of the piston rod is connected to the cylinder via the groove and the fluid passage. Although it communicates with the inner space, when the handle is turned and the cylinder rotates, the opening is removed from the groove and the grooved circular hole is sealed off (sealed) from the cylinder inner space, and the rod is fixed to the cylinder. The lifting and lowering of the piston rod results in a movement that expands or compresses the fluid inside the grooved circular hole, which presents an extremely large resistance. Therefore, when the steering wheel is turned, the suspension system of the present invention exhibits a large resistance to the raising and lowering of the piston rod, that is, to the expansion and contraction of the distance between the axle and the vehicle body, and prevents the vehicle body from tilting.

FIG. 1 shows an embodiment of the present invention. In Fig. 1, a free piston 2 is installed inside the cylinder 1, and this free piston 2 causes the cylinder 1 to
The inside of the chamber is divided into a liquid chamber 3l and a gas chamber 3g. A piston 4 is installed in the liquid chamber 3l so as to be slidable in the vertical direction, and a piston rod 5 integrated with the piston 4 comes out of the cylinder 1 in a liquid-tight state, and an upper spring is attached to the end of the piston rod 5. The receiver 6 and the atsupa support 7 are fixed. cylinder 1
A ring 8 is fixed to the outer periphery of the ring 8, and a lower spring receiver 9 is mounted on the ring 8 via a bearing, and a coil spring 10 for suspension is inserted between the upper spring receiver 6 and the lower spring receiver 9. ing.
Since the lower spring receiver 9 is rotatable relative to the first cylinder 1 in this way, even if the handle is turned off and the cylinder 1 rotates, the coil spring 10 does not rotate.

The piston 4 has four holes 4 near the center.
a, and four holes 4b are drilled at positions far from the center, and the valve member 12 held by the coil spring 11 on the upper surface of the piston 4 is inserted into the holes 4.
b is closed, and a valve member 14 pressed by a coil spring 13 on the lower surface closes the hole 4a.
In this piston 4, the liquid chamber 3l is divided into two parts, a lower part 3l ₁ and an upper part 3l ₂ .

A rod 20 is fixed (fixed to the cylinder) on the axis of the cylinder 1 and has a flow path 20a whose lower end opens into the lower liquid chamber _3l1 and whose upper end opens on the side surface. , holes 5e ₁ , 5e ₂ having circular cross-sections are formed so as to come into sliding contact with the rod 20, and these holes communicate through a communication port 5d. A free piston 21 is inserted into the hole 5e ₂ , and the free piston 21 separates the liquid chamber 5l ₁ from the gas chamber 5l ₂ . On the inner wall of liquid chamber 5l ₁ ,
A groove 5c is formed along the axial direction and ends slightly above the lower surface of the piston 4, and the upper opening of the flow path 20a of the rod body 20 faces the groove 5c in a normal state (vehicle traveling straight). FIG. 2 shows a cross-sectional view taken along the line ₁ of the liquid chamber 5l. In addition, in Figure 1, 5b
is a stopper that limits the upward movement of the piston rod 5 at a certain point. A liquid such as oil is sealed in the liquid chamber 3l. Numeral 19 is a nut, to which wheels are attached.

Next, the operation will be described. When the knuckle 19 rises, the cylinder 1 rises accordingly. At this time, the piston 4 descends with respect to the cylinder 1, and during this time the oil pressure in the lower liquid chamber _3l1 increases, which pushes up the valve member 12 through the hole 4b and escapes into the upper liquid chamber _3l2 . The free piston 2 descends by an amount corresponding to the increased length of the rod 5 into the cylinder 1. When the knuckle 19 descends, the cylinder 1 descends accordingly. At this time, the piston 4 rises with respect to the cylinder 1, and during this time the oil pressure in the upper liquid chamber _3l2 increases, which pushes down the valve member 14 through the hole 4a and escapes into the lower liquid chamber _3l1 . The free piston 2 rises by the amount by which the penetration length of the rod 5 into the cylinder 1 is reduced. The vibration transmitted from the wheels is absorbed by the coil spring 10, and the vibration of the coil spring 10 is absorbed by the movement of the piston 4 relative to the cylinder 1.
The oil is absorbed in a suppressed manner by the oil in the liquid chamber 3L. When performing such an operation, when the vehicle is traveling straight, the upper end opening of the flow path 20a faces the groove 5c as shown in FIG. Groove 5c
The liquid chamber _5l1 communicates with the liquid chamber _3l1 through the flow path 20a, and the liquid in the liquid chamber _5l1 does not particularly impede the movement of the piston rod 5 up and down.

Next, I will explain what happens when you tighten the handle.
When the handle is turned, the cylinder 1 rotates, whereby the upper opening of the flow path 20a is removed from the groove 5c and the flow path 2
0a and the groove 5c no longer communicate with each other. Since the groove is closed at the bottom of the piston 4, the liquid chamber _3l1 is sealed, and when the piston rod 5 tries to go down, the liquid in the liquid chamber _5l1 is compressed, and the free piston 21 rises due to the pressure, causing the gas to flow out. The gas (air) in chamber _5l2 is compressed. Therefore, when the handle is tightened, the gas in the gas chamber _5l2 exerts a large resistance to the downward movement of the piston rod 5.
When the piston rod 5 rises, the free piston ₂₁ descends to the position shown in FIG. becomes. Therefore, when the steering wheel is tightened, the suspension system of the present invention has extremely high resistance to expansion and contraction, and prevents the vehicle from tilting.

In the above embodiment, the gas chamber _5l2 is formed to provide a cushioning effect and reduce the resistance to the downward movement of the piston rod 5. However, for example, a small hole may be formed in the wall of the rod 5 and Therefore, the liquid chambers 5l ₁ and 3l ₂ are connected, and the gas chamber 5
l ₂ may be omitted.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line -1. 1: Cylinder, 2: Free piston, 3l: Liquid chamber, 3l ₁ : Lower liquid chamber, 3l ₂ : Upper liquid chamber, 4: Piston, 5: Piston rod, 5b: Stopper, 5
c: Groove, 5l ₁ : Liquid chamber, 5l ₂ : Gas chamber, 6: Upper spring holder, 7: Atsupa support, 9: Lower spring holder, 10, 11, 13: Coil spring, 1
2, 14: Valve member, 19: Knuckle, 20: Rod, 21: Free piston.

Claims (1)

[Claims] 1. In a strut-type suspension device, a piston with a fluid flow path is slidably mounted in a cylinder, and the ends of a suspension spring are engaged with a piston rod connected to the piston and a cylinder, respectively. and forming a grooved circular hole in the piston rod, and inserting into the hole a rod with a circular cross section fixed to the cylinder and having a fluid passage with one end opening into the inner space of the cylinder and the other end opening on the side surface,
The strut type suspension is characterized in that the hole and the fluid passage are configured to communicate with each other at a relative position between the cylinder, the piston, and the piston rod when the vehicle is traveling straight, but not communicate with each other when the vehicle is at a relative position when the vehicle is curved. Device.