JPS619375A - Steering gear for front/rear wheels - Google Patents

Abstract

PURPOSE:To perform alignment automatically as well as to eliminate any error in steering angle variations at both sides, by making up an engaging part between an eccentric shaft at a rear end part of an input shaft in a backward steering system and a joint member, connectedly supporing tie rods at both sides, as a taper engaging part. CONSTITUTION:An eccentric shaft 22 is projectingly installed in the rear end of an input shaft 20 to be rotated by handle operation. Then, an engaging member 24 is attached to the top of the said eccentric shaft 22 via a bell 23. In addition, an engaged member 31 is tightly installed in a joint shaft 30 which connectedly supports tie rods 15 at both sides. And, a male taper surface 26 is formed in the said engaging member 24 while a female taper surface 34 is formed in the engaged member 31 being opposite to the said make taper surface 26. The engaging member 24 and the engaged member 31 are engaged with each other and assembled down via a roller 36. With this taper engagement, alignment for the input shaft 20 is automatically performable.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a steering device for front and rear wheels of a vehicle.

(Prior Art) In the four-wheel steering system of a vehicle, the present applicant has filed a patent application as one of the so-called symmetrical function type steering systems in which the rear wheels have the same maximum steering angle as the front wheels in the same phase and in the opposite phase. Showa 57-933
No. 94 (Japanese Unexamined Patent Publication No. 58-209657). In this steering system, a joint member that connects and supports the left and right rear wheel tie rods is rotatably fitted to an eccentric shaft -1- provided at the rear end of the input shaft of the rear wheel steering system that rotates in conjunction with the steering wheel. Furthermore, this joint member is supported on the vehicle body via a link mechanism to restrict the swinging of the joint member.

In addition, prior to this, the present applicant had filed a patent application No. 56-12718.
No. 8 (Japanese Unexamined Patent Publication No. 58-30869) proposes a steering system in which the eccentric shaft and a joint member are slidably engaged, and the joint member can only be moved in the left-right direction.

(Problems to be Solved by the Invention) The steering system disclosed in Japanese Patent Application No. 57-93394 has the following technical problems.

First of all, since a link mechanism is used to restrict the swinging of the joint member, it is necessary to take up space for this, making the device as a whole not compact, and making it difficult to check performance before entering or leaving the vehicle. , the attachment of the link to the car body is difficult both in terms of strength and precision. In addition, since a link mechanism that extends to the sides of the vehicle body is used, the structure is asymmetrical, and the relationship between the rotation of the input shaft and the left-right position of the ball joint is slightly different between counterclockwise and clockwise rotations, so it is difficult to change the left-right steering angle. cause an error.

Specifically, the rear wheel tie rods are connected to the left and right sides of the joint member via ball joints, but since the joint member performs synthetic interlocking in the left and right direction and -1 = downward direction,
Since the ball joint moves up and down, there is an error in setting the rear wheel steering angle. In addition, if the ball joint is placed far from the center of the joint member, the force applied to the link mechanism will increase and there will be a limit in strength and rigidity.Therefore, there will be restrictions when determining the position of the ball joint to match the suspension. It is difficult to freely combine it with various types of suspension.

Furthermore, since the input shaft is supported by being attached to the vehicle body using a relatively thin holder, force is concentrated and soft mounting rubber cannot be used, making it difficult to insulate sound and vibration.

On the other hand, according to the steering system disclosed in Japanese Patent Application No. 56-127188, since the circumference of the eccentric shaft is directly engaged with the joint member, precision is required for alignment, and in particular, the occurrence of clearance in the radial direction at the engagement part is avoided. There are technical issues that make it difficult.

The present invention has been made to solve the technical problems in both the above-mentioned steering systems, and its purpose is as follows.

It has the advantages of both steering systems at the same time, that is, it can make the entire device more compact, eliminate errors in left and right steering angle changes and set steering angles, and be adaptable to a wide variety of suspension systems. To provide a highly practical front and rear wheel steering device that realizes automatic alignment between the front and joint members, and also enables the use of a soft mount 1 and a right mount to isolate sound and vibration. .

(Means for Solving the Problems) Therefore, the present invention provides an eccentric shaft (22) provided at the rear end of a human power shaft (20) of a rear wheel steering system that rotates in conjunction with a steering wheel;
The left and right rear wheel tie rods (15) and (+5) are connected and supported, and are slidably engaged with a joint member (30) supported on the vehicle body so as to be horizontally movable in the left and right directions. In the steering device for front and rear wheels, the engagement portion between the eccentric shaft (22) and the joint member (30) is connected to the eccentric shaft (22).
Tapered engagement portions (37) located on the left and right sides and formed in the vertical direction, where the distance between the left and right is larger at the front than at the rear (37)
It is characterized by being configured as

Specifically, the tapered engagement portion (37) is connected to the eccentric shaft (2).
2) A male taper member (24) installed with a ball (23) interposed thereon, an acid taper member (33) integrated into the joint member (30), and a taper of both taper members. It consists of a roller (36) whose axis is horizontal, which is interposed between the surfaces (2B) and (34).

(Function) In this way, since the eccentric shaft (22) and the joint member (30) are slidably engaged at the left and right taper engaging portions (37), the centripetal action of the tapered engaging portions (37) automatically Center alignment can be performed, and in particular, changes in the left and right steering angle of the rear wheels and the set steering angle can be maintained with high precision.

(Embodiment) A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of the steering angle dispersion generating mechanism of the rear wheel steering system showing the main part of the present invention, FIG. FIG.

As shown in Figure 3, the support shaft (2) of the handle (1) is built into a rack and pinion gearbox (3), and tie rods (5) are connected to both ends of the rack shaft (0). ,
Knuckle arms (8), (8) supporting the front wheels (7), (7) are connected to the tie rods (5), (5), and as is known, the front wheels (7), (7) are connected to the handle (1). is steered in the steering direction.

The pinion shaft (
8) is connected to a long linkage shaft (
10) are connected, and a universal joint (10) is connected to the rear end of the shaft (10).
1), an input shaft (20) of a rear wheel steering system is connected thereto. As shown in FIG. 1, a flange (21) is formed at the rear end of this input shaft (20), and an extremely short eccentric shaft (22) is provided protruding from this flange (21).

On the other hand, as shown in Fig. 3, the tie rods (15), (15) connected to the knuckle arms (1B), (1B) supporting the rear wheels (17), (17) are connected to ball joints (13), (15), respectively.
13), and is connected and supported to both ends of the joint shaft (30). As shown in FIG. 1, an engaged member (31) is fixedly provided at the center of the joint shaft (30). That is, the engaged member (31) is fixed and integrated in the center of the joint shaft (30) from the rear with two bolts (39), (39) using the cylinder part (32), and the joint shaft (30) protrudes forward. Female tapered surfaces (34), (34) facing forward are formed on opposing surfaces of the two left and right vertical wall portions (33), (33).

The engaging member (24) is mounted on the eccentric shaft (22) by interposing balls (23), and the eccentric shaft (22) is provided with a contact type angular bearing. Male tapered surfaces (2B), (2B) facing rearward are formed on the side surfaces of the left and right vertical walls (25), (25) of this engaging member (20).These male tapered surfaces (2B), (213) There are stopper protrusions (27), (27), (27) at the upper and lower ends of the
(27) is projected.

Furthermore, the engaging member (24) and the engaged member (31) are sometimes engaged and assembled using both the left and right tapered surfaces (2B), (3
4), (2B), and (34), as shown in Fig. 2, rollers (36) whose axes are horizontal are held by retainers (35), (35)..., (ae), ... respectively.

The above input shaft (20) and joint shaft (30) are connected to a box (41) at the center and pipes (42) at the front and left and right sides.
), (43), holder (40) integrally formed with (43)
Supported by i.e. the box (41) of the holder (40)
Insert the joint shaft (30) with the engaged member (31) facing inside.
) is supported in the left and right pipes (43), (43) by metal bearings (40 degrees (44) so that it can slide horizontally from left to right.), and the eccentric shaft (22) is supported in the box (
41) and the engaging member (20) facing inside the engaged member (20).
31) through rollers (36), (3B), etc., and the input shaft (20) is rotatably supported in the front pipe (42).

Specifically, the input shaft (20) is supported by installing a ring (28) on the front part of the flange (21) at the rear end with a ball (28) interposed therebetween, and using a contact type angular bearing. The ring (28) is lightly fitted to the inner periphery of the base end of the pipe (42). Then, apply the thrust washer (51) to the front surface of the ring (2θ), screw and insert the sleeve (50) into the pipe (42), and then insert the sleeve (50) into the pipe (42).
Abut the rear end against the washer (51). Sleeve (50
) and the input shaft (20), a coil spring (52) is placed in this space, and a step (53) at the middle of the inner circumference of the sleeve (50) and the input shaft (20) are provided. A spring (52) is compressed between the washers (51) and preloaded to bias the ring (51) rearward.

Furthermore, a locking nut (55) is screwed onto the sleeve (50).

Further, a roller bearing (56) is interposed between the front end of the sleeve (50) and the input shaft (20), and a seal cap (56) is interposed between the front end of the sleeve (50) and the input shaft (20).
7) to be crowned.

In this way, the opening of the box (41) is closed with the cover (45), the input shaft (20) is aligned with the left and right center line of the vehicle body, and the left and right pipes (43) are connected to the soft mounting rubber (4B). , (48) are interposed and supported by the vehicle body side brackets (47), (47). In addition, the left and right ball joints (13).

(13) is covered with compact rubber boots (48) and (4B) fastened with bands to the ends of the pipe (43) and the tie rod (15), respectively.

In the above steering system settings, the eccentric shaft (22) is connected to the input shaft (2
0), for example, vertically downward as shown in Figure 2, and when the front wheels (7), (7) are steered to the right, the eccentric shaft (22) will rotate clockwise in Figure 2. Set the crank to rotate.

Therefore, as the crank rotates from the initial position of the eccentric shaft (22), if the day shift angle is less than 180'', the rear wheel (17) will move.

(17) is steered in the same direction as the front wheels (7), (7), in this case the rear wheel steering angle of 90@ is maximum, and further 180
”, the steering angle is in the opposite direction, and the rear wheel steering angle is maximum at 270°, and the rear wheels (17) and (17 ) have the same maximum steering angle.

Then, the eccentric shaft (22) and the joint shaft (30) are slidably engaged with each other at the tapered engaging portion (37), that is, the eccentric shaft (22) is interposed with a pole (23), and the male Tapered member (24)
is installed, and the joint shaft (30) is equipped with left and right acid taper members (33), (33) integrated, and both male and female tapered surfaces (2B), (34), (2e), (3o) Since the rollers (36)..., (3B)... are interposed, friction can be minimized, and automatic centering can be performed by the centripetal action of the tenor.

Moreover, the joint member that connects and supports the rear wheel tie rods (15), (15) is a joint shaft (30) that does not swing in the vertical direction, that is, it moves horizontally only in the left and right direction, and the ball joint (13), Since (13) is set to 1 to prevent vertical rocking, errors in left and right steering angle changes can be prevented by 11, and setting errors in the rear wheel steering angle can also be prevented by 1, making it easy to check performance. can.

Further, such a rear wheel steering system does not require a link mechanism and the eccentric shaft (22) can be made as short as possible, so the device can be made compact and the left and right shapes can be symmetrical.

Furthermore, you can select joint shafts (30) with different lengths to match the suspension model.

There are no restrictions on the arrangement of (13).

In addition, the left and right pipes (43), (43) of the holder (40)
) part has a wide span □ to support the vehicle body, so even if soft mount rubber (4B) and (4B) are used, high rigidity is achieved, which is also advantageous in blocking sound and vibration. Become.

By the way, as in the embodiment, the sleeve (50) is attached to the holder (
40) in the front pipe (42), and the position of the input shaft (20) can be adjusted by the sleeve (50) via the washer (51) and angular ball bearings (28) and (29). , Rock Nala) (
55), the engagement relationship can be adjusted.

Furthermore, if the preload spring (52) presses the input shaft (20) backward through the washer (51) and the angular ball bearings (2B) and (29), play in the tapered engagement portion (37) can be prevented. This can be prevented, and the state of retention can be maintained well even during long-term use.

(Effects of the Invention) As described in I- below, according to the front and rear wheel steering device of the present invention, in particular, the eccentric shaft and the joint member that moves horizontally in the left and right direction are slidably engaged at the tapered engagement portion. , it is possible to make the device more compact, eliminate errors in the rear wheel steering angle, and apply it to a variety of suspensions, as well as automatically align the eccentric shaft and joint member, maintaining the steering angle with high precision. It is highly practical as it also allows the use of soft mount rubber, which is advantageous in blocking sound and vibration.

The taper engaging portion is made of a male taper member mounted on an eccentric shaft with a ball interposed therebetween, a thin acid taper material integrally attached to the joint member, and interposed between the tapered surfaces of both taper members. If the roller is configured with a roller whose axis is horizontal, sliding friction can be minimized and smooth operation can be achieved.

[Brief explanation of the drawing]

Figure 1 ° is a cross-sectional view of the steering angle dispersion generating mechanism of the rear wheel steering system showing the main part of the present invention, Figure 2 is a cross-sectional view taken along the line ■-II in Figure 1, and Figure 3 is the steering ridge device. It is a schematic perspective view of the whole. In the drawing, (1) is the handle, (15) is the tie rod for the rear wheel, (20) is the input shaft, (22) is the eccentric shaft, (23)
is a ball, ('24) is a male taper member, (2B) is a male taper surface, (30) is a joint member, (33) is an acid taper member, (34) is an acid taper surface, (36) is a roller,
(37) is a tapered engagement portion. Patent Applicant Honda Motor Co., Ltd. Agent Patent Attorney 2) Part 1 Patent Attorney Kuni Ohashi Patent Attorney Yun Koyama 61-9375 (5)

Claims (2)

[Claims] (1) Connect and support the eccentric shaft provided at the rear end of the input shaft of the rear wheel steering system that rotates in conjunction with the steering wheel, and the tie rods for the left and right rear wheels, and support it on the vehicle body so that it can move horizontally in the left and right direction. In a vehicle steering system, the engagement portion between the eccentric shaft and the joint member is slidably engaged with the joint member so that both the front wheels and the rear wheels are steered by steering operation of the steering wheel. 1. A steering device for front and rear wheels, characterized in that it is configured as a tapered engagement portion located left and right with respect to an axis, formed in a vertical direction, and in which the distance between the left and right is larger at the front than at the rear. (2) In claim 1, the tapered engaging portion includes a male tapered member mounted on the eccentric shaft with a ball interposed therebetween, and a female tapered member integrated with the joint member. and a roller whose axis is horizontal, which is interposed between the tapered surfaces of both tapered members.