JPH0143642B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power hop prevention mechanism for an equalizer type suspension that suspends two rear wheel axles of a large vehicle or the like.

[Conventional technology]

Conventionally, in equalizer type suspensions in which the two rear axles, including the drive shaft, are supported by leaf springs connected by each equalizer beam, the load is distributed between the two rear axles by a so-called power hop when the vehicle starts backwards. When movement occurs, the wheels of the drive axle are momentarily lifted off the ground completely, and as a result, the load of the vehicle body is supported by the wheels of the dead axle, and the driving force is not lost. It becomes difficult to start backwards smoothly. Further, in such a case, an excessive force is applied to only one of the leaf springs supporting each axle, which is not preferable.

To explain this in detail, as shown in FIG. 1, the rear wheel consists of a double tire 32 and a single tire 33 arranged behind this, and each is attached to the frame 14 with leaf springs 29 and 17. It is gaining support. The leaf spring 29 has an intermediate portion connected to a drive shaft 26 having double tires 32 with a known U bolt or the like, and a front end connected to the frame 1.
4 through a bracket 3, and is slidably supported under a fulcrum portion 4, and its rear end is connected to and supported by a floating pin 8. Leaf spring 17 for rear wheel
The intermediate portion is connected to the dead shaft 18 that supports the single tire 33 using the U bolt, the front end is connected to and supported by the floating pin 13, and the rear end is a fulcrum fixed to the frame 14 via a bracket 16. It is slidably supported on the underside of 15.

Reference numeral 23 denotes an equalizer beam, whose intermediate portion is supported by a bracket 9 swingably attached to a frame 14 through a pin 10, and which is rotated around the aforementioned pin 8 via a pin 24 at the front end of the beam 23. A link 25 is also connected to the aforementioned pin 1 via a pin 21 at the rear end of the equalizer beam 23.
Links 12 that rotate around 3 are connected to each other.

A support member 28 is fixed to the drive shaft 26, and a front torque rod 30 is connected between the support member 28 and the aforementioned bracket 3 through pins 2 and 31 provided at both ends, respectively. Similarly, a rear torque rod 20 is connected by pins 22 and 19 between a support member 34 fixed to the dead shaft 18 and the lower end of the bracket 9.

When the vehicle is suddenly started backwards from the state shown in FIG. 2, the torque reaction force generated on the drive shaft 26 exerts a force on the pin 31 of the front torque rod 30 to push it diagonally backward. , since this is prevented by the front torque rod 30, the spring 29 is momentarily bent, and its front end is slid forward on the lower surface of the fulcrum 4 in the direction of the arrow U centering on the pin 31. torque is generated.
As a result, the double tire 32 lifts up (power hop), rotates the link 25 to the right around pin 8, and similarly rotates the equalizer beam 23 to the right around pin 10.
is rotated to the right to shift the vehicle body load to the single tire 33 side. Due to the above operation, the driving force of the double tires 32 becomes insufficient and the tires slip. This phenomenon also occurs when the brakes are applied while the vehicle is moving forward.

In addition, Japanese Patent Publication No. 49-4164 discloses that in a vehicle in which the drive shaft is suspended using a leaf spring and a torque rod, the torque rod is abolished and the axle tube bracket and vehicle body are removed in order to eliminate the drawback of inducing power hops, especially when starting from the rear. There are wind-up prevention devices for vehicle suspension systems that connect cables between the vehicle suspension brackets, but although these devices can prevent the induction of power hops due to torque clots, they do not reduce the torque reaction force that acts on the axle tube when starting backwards. Since there is no way to suppress it, the occurrence of windup is inevitable.
Even so, if the rear wheel has a single axle, the connection between the differential and the propulsion shaft will only fall, but if the rear wheel has two axles and an equalizer suspension, the torque reaction force on the drive shaft will The equalizer beam will move backwards, the vehicle load will shift from the drive shaft to the dead shaft, and the ground contact driving force of the drive wheels will be lost, which may impede smooth starting backwards. It is necessary to increase the strength of the suspension.

Furthermore, in order to prevent pop-up, the cable in the above-mentioned Tokko Sho was connected between the bracket of the axle tube and the bracket of the vehicle body behind it (specifically, the pin supporting the end of the leaf spring), and for the above reason, a torque rod was also provided. In this case, at the time of a pop-up, the cable is pulled by the pivoting movement of the axle tube bracket around the fulcrum on the axle tube side of the torque rod, which is the momentary center, to prevent the pop-up, but if the drive axle side wheel runs over a step. When the bracket of the axle tube pivots around the front end of the torque rod, a large component of force is generated that pulls the cable, which may impede the free vibration of the leaf spring.

[Problem that the invention seeks to solve]

SUMMARY OF THE INVENTION An object of the present invention is to provide a power hop prevention mechanism that suppresses the behavior of the wheels due to power hops when a vehicle equipped with an equalizer suspension as described above is started backwards and when braking while running forward.

[Means to solve the problem]

In order to achieve the above object, the present invention has a configuration in which front and rear torque rods 30, 20 are connected to the vehicle body side forward of two rear axles 26, 27 including a drive shaft 26 suspended by an equalizer type suspension. A movable pin 5 is provided above the drive shaft 26 of the vehicle and pivots around the front end of the front torque rod 30 when the drive shaft side wheels 32 run over a bump, and a movable pin 5 is provided above the drive shaft 26 and rotates with the drive shaft 26 when the drive shaft side wheel 32 runs over a bump. A flexible member 6 is stretched between fixing pins 7 provided on the vehicle body on a straight line extending toward the vehicle body.

[Effect]

The flexible member 6 stretched between the movable pin 5 provided at the upper end of the support member 27 attached to the drive shaft 26 and the fixed pin 7 provided on the frame 14 is aligned exactly with the pin 2 of the front torque rod 30. Since the pin 5 is arranged as shown in FIG.
The vehicle can move without resistance in the direction of the arrow v, which is approximately perpendicular to the above-mentioned straight line with the center at The movement of the system in the direction of arrow u due to the power hop action is suppressed.

[Embodiments of the invention]

The present invention will be explained based on the embodiment shown in FIG. 1. The present invention will be explained based on the embodiment shown in FIG. The movable pin 5 is supported at the upper end of the support member 27 connected to the shaft 26 directly above the shaft 26, and
A fixed pin 7 is supported on the frame 14, and a flexible member 6 such as a wire is connected between these pins 5 and 7 so that it is slightly loosened or bent during stationary and normal running, and a flexible member 6 such as a wire is connected to the drive shaft. The pin 2, which is the center of the turning movement of the motor vehicle 26, and the aforementioned moving pin 5 and fixed pin 7 are arranged so that they are substantially aligned in a straight line when the vehicle is stationary.

As described above, the present invention is arranged such that the flexible member 6 stretched between the movable pin 5 provided on the support member 27 and the fixed pin 7 provided on the frame 14 is exactly aligned with the pin 2. The double tires 32, leaf spring 29, and torque rod 30 of the drive shaft 26 are
The system can be prevented from moving in the direction of arrow u due to the power hop effect.

That is, when starting backwards and braking while traveling forward, the movable pin 5 of the support member 27 momentarily bends the leaf spring 29 and attempts to rotate about the pin 31 in the direction of the arrow U; The flexible member 6 holds the movable pin 2 and the fixed pin 7 on a straight line, and the pin 5 does not move in the direction of the arrow u.
On the other hand, when the tire 32 rides on a step on the road surface and the leaf spring 29 is bent, the drive shaft 26 moves in the direction of the arrow v, which is approximately perpendicular to the straight line, centering on the pin 2, and the leaf spring 29 acts as a buffer. There is nothing you can do to prevent it.

〔Effect of the invention〕

As described above, the present invention is directed to a vehicle in which front and rear torque rods are connected to the vehicle body side forward of two rear axles including a drive shaft suspended by an equalizer type suspension, and a front torque rod is provided above the drive shaft at the front end of the front torque rod. between a movable pin that rotates with the drive shaft when the drive shaft side wheel runs over a step, and a fixed pin provided on the vehicle body on a straight line that passes through the above pin and extends from the front end of the front torque rod toward the vehicle body when the vehicle is stationary. Since the flexible member is stretched, it is suspended by the eco-riser type suspension, and while ensuring the freedom of vertical movement of the drive shaft among the two axles, it is possible to use the drive shaft when starting backwards or when driving forward. Power hops that occur on the drive shaft during braking extend from the front end of the front torque rod toward the vehicle body through a moving pin that pivots with the drive shaft when the drive shaft side wheel runs over a bump, and the moving pin when the vehicle is stationary. A flexible member is stretched between fixed pins installed on the vehicle body in a straight line to prevent slipping or floating of the drive shaft side tire that occurs when starting backwards or braking while driving forward. In addition to improving the driving force, it reduces the significant load transfer between the two axes of the equalizer type suspension, making it unnecessary to increase the strength corresponding to the moving load, resulting in the effect of reducing the weight and cost of the vehicle.

[Brief explanation of drawings]

FIG. 1 is a side view showing the structure of a conventional equalizer type suspension, and FIG. 2 is a side view showing the structure of an equalizer type suspension equipped with a power hop prevention mechanism according to the present invention. 3, 9, 16: bracket, 4, 15: fulcrum, 5: moving pin, 7: fixed pin, 6: flexible member, 12, 25: link, 14: frame, 1
7, 29: leaf spring, 18: dead shaft, 30: front torque clot, 20; rear torque clot, 23: equalizer beam, 26: drive shaft, 27, 28,
34: Support member, 32: Double tire, 33: Single tire.

Claims (1)

[Claims] 1 Drive shaft side wheels centered on the front end of the front torque rod provided above the drive shaft of a vehicle in which front and rear torque rods are connected to the vehicle body side forward from the rear two axles including the drive shaft suspended by an equalizer type suspension. A flexible member is stretched between a movable pin that rotates with the drive shaft when the vehicle runs over a bump, and a fixed pin that is provided on the vehicle body on a straight line that passes through the pin and extends from the front end of the front torque rod toward the vehicle body when the vehicle is stationary. Power hop prevention mechanism of the equalizer type suspension.