JPS59118578A - Arrangement of steering gear box - Google Patents

Abstract

PURPOSE:To eliminate the difference between the inputs to the shafts of a steering gear having a right and a left universal joints different from each other in the angle of connection between a right and a left drive shafts and the axles of a right and a left front wheels, by arranging the box of the steering gear obliquely. CONSTITUTION:Drive shafts 3R, 3L different in length are coupled to the right and left output shafts of a differential gear 1 through universal joints 2R, 2L. The axles 5R, 5L of a right and a left front wheels 6R, 6L are coupled to the ends of the drive shafts 3R, 3L through universal joints 4R, 4L different in angle. The box 10 of a steering gear is arranged obliquely. The angle alphaL between a shaft 9 and a tie rod 8L located at the universal joint 4L of larger angle is made more than that alphar between a shaft 9 and a tie rod 8R located at the universal joint 4R of smaller angle. As a result, the difference between the inputs to the right and left shafts of the steering gear is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an arrangement structure of a steering gear box in an automobile.

In the case of a front-wheel drive vehicle, the differential gear is displaced from the center line of the vehicle in the left-right direction, and the left and right drive shafts are of unequal length.
The angles of the left and right constant velocity joints on the left and right wheels are different from each other, and the difference in angle between the left and right constant velocity joints causes an unbalanced rotational moment of the left and right wheels with respect to the king pin shaft, and the human force applied to the shaft of the steering gear box that receives this moment is generated. This has the problem of causing a difference between the left and right sides, which increases driver fatigue.

One way to deal with this problem is to mount the entire power unit, which consists of the engine, transmission, differential gear, etc., on the vehicle body at an angle, thereby making the right and left joint angles of the drive shafts of unequal lengths equal. (Refer to Publication No. 49-20039), or a method in which the engine and transmission are mounted horizontally as before, and only the differential gear fixed to the transmission is tilted to equalize the left and right joint angles of the drive shafts of unequal length ( Japanese Unexamined Patent Publication 1973-
138235) etc. have been developed.

The present invention does not require troublesome and time-consuming means such as changing the mounting structure on the power unit side or changing the relationship structure between the transmission and the differential gear as in the above-mentioned conventional measures, and has an extremely simple structure that allows the steering gear to be adjusted. It is an object of the present invention to provide a device that eliminates the difference in left and right human forces applied to the box shaft and eliminates problems such as runaway and increased driver fatigue.The present invention will be described below with reference to the accompanying drawings.

In FIG. 1, 1 is a differential gear, and the left and right output shafts of the differential gear 1 are connected to the left and right drive shirts 3L and 3R via constant velocity joints 2L and 2R, respectively.
and 31 (constant velocity join at this tip) 4L and 4R to the left and right front wheels 6L, 6R's respective rotating shafts 5L and 5R7! l'' are connected.

When the differential gear 1 is in a position displaced in the left-right direction as shown in the figure with respect to the center line If the output shaft of No. 1 is almost horizontal in the natural mounting state of the power plant, it is natural that the angle between the drive shaft and the rotation axis of the front wheel, that is, the angle of the constant velocity joint on the wheel side, will be different on the left and right sides. be.

Generally, in a constant velocity joint, when the intersection angle between the driving shaft α and the driven shaft is θ as shown in Fig. 2, the secondary moment m acting on the driven shaft of the constant velocity joint c is
is m = Ttan';.

(However, T is the transmitted torque, so if there is a difference between the angles θL and θR of the left and right wheel-side constant velocity joints as described above, a difference will occur in the left and right secondary moments, and that moment difference will be reflected by the knuckle arm 7L. , 7R and tie rod 8L,
The steering gear box 1r is manually powered by a shaft 9 which is slidably supported in the width direction of the steering gear box 1r via the shaft 8R.

Therefore, in the present invention, the steering gear box 1 (1
' As shown in Fig. 1, the angle αL between the tie rod 8L and the shaft 9 on the side of the joint angle 411 is the angle αL between the tie rod 8R on the side with the smaller joint angle and the shaft 9.
hb is configured to be larger than R.

That is, due to the axial force RI of one tie rod 8L, 1
The force pushing the tie rod 119 in the axial direction is expressed as RLαL−μRLαL, and the force in the axial direction of the other tie rod 8 is expressed as RR.
The force pushing the shaft 9 in the axial direction is RR(2)αR−μ
It is expressed as RRαR. However, in the above, μ indicates the friction coefficient of the bearing that supports the support 9 in the gear box.

The secondary moment caused by the angle of the constant velocity joint on the rear wheel side is -7 on the joint angle θh + θL (constant velocity joint) 4L side, and the second moment is -7 on the other constant velocity joint 4R@lI, so the knuckle If the lengths of the arms 7L and 7R are H, the axial forces RR of one tie rod and the other tie rod 8R are respectively expressed by and.

Therefore, as noted in 611, the steering gear box 1
0 is installed at an angle, and the angles αL and αR between the shaft 9 and the left and right tie rods 8L and 8R are set to become Even if an unbalanced moment occurs around the king pin, the unbalanced moment is caused by the angles αL and αR formed between the gearbox shaft 9 and the left and right tie rods 8L and 8R.
As a result, there is almost no difference in the amount of human power applied to the shaft 9 between the left and right sides, and problems such as the driver losing control of the steering wheel or veering off the road can be almost completely prevented.

In Fig. 1, 11 is the steering wheel 12
is a steering shaft, and a pinion is connected to the tip of the steering shaft 12 directly or via another intermediate shaft, and the pinion meshes with rack teeth provided on the gear box shaft 9 to rotate the steering handle 11. As a result, the gear box shaft 9 slides in the axial direction, and the tie rods 8L, 8R and knuckle arm 7
Steering is performed by rotating the front wheels 6L and 6R in the steering direction via L and 7R, but this configuration has been commonly used and well known as a binion rack type steering device. Therefore, detailed explanation and illustration will be omitted.

As described above, according to the present invention, in a front wheel drive vehicle in which the left and right drive shafts have unequal lengths and the left and right wheel side constant velocity joint angles are different, the output shaft of the differential gear on the power unit side is tilted, and the left and right drive shafts are driven at a constant velocity. Without the need for a complicated configuration to equalize the joint angles, the steering gear box is simply tilted and attached to a single side member, and the constant velocity joint angle with the gear box shaft slidably supported by the steering gear box is adjusted. The unbalanced moment around the king pin caused by the difference in constant velocity joint angles can be reduced to This eliminates the difference in the angle between the gearbox shaft and the left and right tie rods, eliminates the difference in human power applied to the gearbox shaft from left to right, and prevents problems such as increased driver fatigue and yaw. It is easy to set the angle between the box shaft and the left and right tie rods, it can be easily applied to existing vehicles, and together with the low cost, it can bring about great practical effects.

[Brief explanation of the drawing]

Fig. 1 is an explanatory plan view showing an embodiment of the present invention, and Fig. 2 is an explanatory view illustrating the secondary moment generated on the driven shaft side due to the constant velocity joint angle. 1...Differential gear, 3L, 3R...drive shaft, 4L,
4R...Single wheel side constant velocity joint, SL, SR...
...J table wheel rotation axis, 7L, 7R...knuckle arm,
8L, 8R... Tie rod, 9... Gear box shaft, 10... Steering gear box. Above 1 Figure 22

Claims (2)

[Claims] (1) In a front-wheel drive vehicle in which the left and right drive shafts are of unequal length and the angle of the heavy wheel side constant velocity joint is different on the left and right, and a binion rack type steering device is used as the steering device, the gear box of the steering device is , so that the angle between the gearbox shaft, which is supported by the gearbox so as to be slidable in the axial direction, and the tie rod on the side where the constant velocity joint angle on the wheel side is larger is larger than the angle between the other tie rod. , a steering gear box arrangement structure characterized in that the steering gear box is attached to a single side member in an inclined manner. (2) If the angles of the left and right wheel-side constant velocity joints are θL and θR, respectively, the length of the knuckle arm is H, and the sliding friction coefficient of the gearbox shaft is μ, then the gearbox shaft and the left and right tie rods are angles αL and α with
The arrangement structure of a steering gear box according to claim 1, wherein R is set to a value that satisfies the equation.