JPS5820567A - Steering gear for vehicle - Google Patents

Abstract

PURPOSE:To ensure the left and right smooth movement of a connecting rod in a steering gear capable of steering front and rear wheels by connecting a connecting rod interconnecting a crank pin coupled with an input shaft and a rear wheel side tie rod connecting rod to another connecting rod through a ball bearing. CONSTITUTION:A rear wheel side steering mechanism in the heading steering gear is provided with an input shaft 25 rotatably interlocked with a steering wheel not shown and aided by a power cylinder 32 with respect to the steering operation. The rotation of the input shaft 25 is transmitted to a connecting rod 19 through a crank mechanism A to move linearly left and right a tie rod 18 for steering the rear wheels. In this case the crank mechanism A is constituted from a crank pin 27 ecentrically coupled with the input shaft 25 and a connecting rod 28 for transmitting the movement of the pin 27 to the connecting rod 19. The connection between said connecting rod 19 and connecting rod 28 provides a ball joint for locating the center I of a ball portion 29a on the axis J of the connecting rod 19.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle steering system that steers front wheels and rear wheels.

The present applicant has previously provided a vehicle steering system in which front wheels and rear wheels are steered by steering operation of a steering wheel. According to this steering device, the rear wheels are steered in addition to the front wheels, so it is possible to eliminate the mismatch between the vehicle direction and the tangential direction of the turning trajectory in a vehicle that steers only the front wheels, and it is possible to eliminate mismatches between the front wheels and the rear wheels. This has advantages such as being able to eliminate the difference in the generation time of lateral force.

By the way, there are various mechanisms that can be used to steer the rear wheels in addition to the front wheels when the steered wheels are operated as described above. A rear wheel steering mechanism is constructed by connecting with a connecting rod that is movable in the width direction, and a crank pin is connected eccentrically in the radial direction of the input shaft to an input shaft that rotates in conjunction with the steered wheels. The crank pin and the connecting rod are connected by a connecting rod, and by the crank movement of the crank mechanism composed of the input shaft, the crank pin, and the connecting rod, the rear wheel steering mechanism is connected to the rear wheel steering mechanism by moving the connecting rod in the width direction of the vehicle body. A mechanism that performs a wheel steering operation is conceivable.

The present invention is aimed at technologically developing the above-mentioned structure and operation mechanism when employing the structure and operation mechanism as described above in a vehicle steering system.An object of the present invention is to connect the connecting portion between the connecting rod and the connecting rod to a ball. joint, and the center of the ball portion of the ball joint is located on the axis center line of the connecting rod, so that the movement of the connecting rod in the width direction of the vehicle body due to the crank movement of the crank mechanism causes a ball joint to the connecting rod. )? When transmitted through the connecting rod, the operating force transmitted from the connecting rod to the connecting rod can be used to move the connecting rod linearly in the width direction of the vehicle body, and the point of application of the operating force and the axial center of the connecting rod can be An object of the present invention is to provide a steering device for a vehicle that can eliminate the occurrence of swinging of a connecting rod due to deviation from a line.

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

Fig. 1 is a plan view showing the main members and structure of a four-wheeled vehicle equipped with the device according to the present invention in solid lines and other parts in chain lines, and Fig. 2 is a plan view of the structure of the rear part of the vehicle shown in Fig. 1. This is a partially enlarged view.

The left and right front wheels 10.10 are each supported by knuckle arms 11 and 41 that are rotatable left and right, and the upper end of the knuckle arm 11 is a shock absorber integrally connected to the vehicle, and the inner end 12a is supported by a shock absorber that swings up and down to the vehicle body. The freely pivoted shock absorber, lower arm 12, etc. constitute a front wheel suspension mechanism that moves the front wheel 10 up and down to follow the undulations of the road surface. On the other hand, the rear wheel suspension mechanism is configured similarly to the front wheel suspension mechanism, and the rear wheels 13, 1,
1-Supported rotatable left and right knuckle arms 14°1
A shock absorber 4 has an upper end connected to the vehicle body, and an inner end 15a is supported by the vehicle body via a lower arm 15 pivotally connected to the vehicle body so as to be able to swing vertically. Front wheel knuckle arm ll, 1
The outer end of a tie rod 16.16 is connected to the outer end of the tie rod 16.16, and the inner end of the tie rod 16.16 is connected to a connecting rod 17 that is movable in the gear box 17 in the left-right direction, that is, in the width direction of the vehicle body.
When the connecting rod 17a moves left and right, the left and right front wheel steering tie rods 16.16 rotate the knuckle arm 11 in the left and right direction and steer the front wheel l.
O is steered. This front wheel steering operation principle is based on the rear wheel 1.
3, the left and right rear wheel steering tie rods 18° are connected at their outer ends to the rear wheel knuckle arms 14, 14.The inner ends of the left and right rear wheel steering tie rods 18 are connected to both ends of the connecting rod 19. When the connecting rod 19 moves left and right, the tension and compression forces acting on the tie rods 18 and 18 cause the knuckle arm 14 to rotate in the left and right direction and the rear wheel 13 to be steered.

The steering wheel 20Fi, which is steered by the driver, is connected to the internal mechanism of the gear box 17 by a steering shaft 21 with a universal joint 21a interposed therebetween, and the internal mechanism controls the rotation of the steering wheel 20 by a connecting rod built into the gear box 17. The internal mechanism has a direction conversion function of converting the movement of the steering shaft 17a into a linear movement in the width direction of the vehicle body, and the internal mechanism includes, for example, a pinion integrally provided at the tip of the steering shaft 21 inserted into the gear box 17, and the connecting rod 17a.
It is constructed by using the rack rod as a rack rod that meshes with the pinion. With this structure, the front wheels 1O are steered by steering the steering wheels 20.

A case 22 is coupled to a position of the gear box 17 that is shifted toward the car body promontory from the connection part with the steering shaft 21.
A connecting shaft 22a connected to the internal mechanism of the gear box 17 is inserted into the inside of the gear box 2. The connecting shaft 22a is an axis that rotates when the connecting rod 17a performs a linear movement in the width direction of the vehicle body.
If a is a rack rod as described above, a pinion that meshes with the rack rod may be integrally provided on the connecting shaft 22a.

The front end of an operating shaft 23 whose axial direction is in the longitudinal direction of the vehicle body is connected to the rear end of a connecting shaft 22a extending from the gear box 17 to the rear of the vehicle body, and the operating shaft 23 is installed between the front part of the vehicle body and the rear part of the vehicle body. The front end of a shaft 25 inserted into the case 24 is connected to the rear end of the shaft 25 . As shown in FIG. 4, the shaft 25Fi is a rotating shaft rotatably supported by bearings 26, 26 of the case 24. When the steering wheel 20 is rotationally steered, the shaft 25 rotates in conjunction with the steering wheel 20 via the connecting rod 17a1, the connecting shaft 22a1, and the operating shaft 23. The rotational force of the shaft 25 is applied to the rear wheel 13
This provides the steering force for steering the vehicle.

A crank pin 27 is provided at the rear end of the shaft 25 so as to protrude toward the rear of the vehicle body, and although the crank pin 27 is parallel to the shaft 25, it is eccentric from the axial center of the shaft 25 by ε in the shaft radial direction.

At the rear end of the crank pin 27 is a connecting rod 2 as shown in FIG.
A connecting pin 29 is connected to the other end of the connecting rod 28 whose length direction is in the vehicle width direction, and the connecting pin 29 is connected to the connecting rod 28 through the connecting pin 29 extending toward the rear of the vehicle body. left and right tie rods 18°18'fr
: The connected connecting rods 19 are connected.

The connection between the crank bin 27 and the connecting rod 28 is achieved by slidingly surrounding the ball holder in which the rear end ball portion 27a of the crank bin 27 is incorporated into one end of the connecting rod 28, and by the connecting pin 27. 29 and the connecting rod 19 is also achieved by having the ball receiver, in which the rear end ball portion 29a of the connecting pin 29 is incorporated in the connecting rod 19, slidably supported by the member 31.

Above shaft 25, crankshaft y 2.7, connecting rod 2
8. A crank mechanism A is configured by the connecting pin 29,
When the shaft 25 rotates, the crank pin 27 rotates along an arc locus around the axis of the shaft 25, so the connecting rod 28
The tensile and compressive forces cause the connecting rod 19 to move linearly in the width direction of the vehicle body, thereby steering the rear wheels 13.

As is clear from the above explanation, front wheel knuckle arm 1
1. A front wheel steering mechanism B is constituted by left and right front wheel steering tie rods 16.16 and a connecting rod 17a interposed between the two tie rods 16.16. Tie rod for rear wheel steering 18.18,
A rear wheel steering mechanism C is constituted by a connecting rod 19 interposed between both tie rods 18 and 18. These front wheel steering mechanism B and rear wheel steering mechanism C are connected to the connecting shaft 22a1.
The operating shaft 23 and the shaft 25, which is also a component of the crank mechanism A, are connected by a connecting path, and when the steering shaft 20 is fully rotated, the front wheel steering mechanism is created by linear movement of the connecting rod 17a in the vehicle width direction. Bp The front wheel steering operation is transmitted to the rear wheel steering mechanism C via the connecting path 1 rank mechanism A as a rear wheel steering operation in which the connecting rod 19 moves linearly in the vehicle width direction. The rear wheels 13 are steered together with the front wheels 10 by the steering operation. Since the rear wheel steering operation of the rear wheel steering mechanism C is performed by the rotational force of the shaft 25 via the connecting shaft 22a1 and the operating shaft 23, the shaft 25 is connected to transmit the entire rear wheel steering force to the rear wheel steering mechanism C. It serves as the input axis for the route.

The linear movement distance of the connecting rod 19 with respect to the rotation angle of the input shaft 25 is a sine value, so that the rotation angle of the input shaft 25 is 180 degrees.
When the rotation angle is within 180°, the front wheels 10 and the rear wheels 13.

The rotation angle of the input shaft 25 with respect to the operating rotation angle of the steering wheel 20 is determined by a speed change means having an arbitrary speed change rate using a gear mechanism or the like between the front wheel steering mechanism B and the connecting path, and furthermore, during the connecting path. can be set appropriately by intervening with In addition to steering in the opposite direction, when operating the steered wheels 20 with a small steering angle, the front wheels 10 and rear wheels 13 are steered in the same direction, and when operating the steering wheel 20 with a large steering angle, the steering angle of the rear wheels 13 is set to zero or It is possible to return it to near zero.

The vehicle is equipped with a power steering device for assisting the driver in steering the steering wheel 20, and the device includes a power cylinder 32 shown in FIGS. 1, 2, and 6. Consists of. The power cylinder 32 is a power auxiliary means, and as shown in FIG. 6, a main body case 34 of the cylinder 32 into which a piston rod 33 slidable in the width direction of the vehicle body is inserted is assembled and integrated with the case 24 of the input shaft 25. Therefore, the structure is made more compact. The piston rod 33 is a rack rod, and the rack rod has teeth 33a.
... has a hinion 25a formed integrally with the input shaft 25.
are in mesh with each other, and the piston portion 33 of the piston rod 33
The internal left and right chambers S1. S
By selectively supplying hydraulic oil to either one of 2, the piston rod 33 behaves in an elongated or contracted manner,
Rotation assisting power is applied to the input shaft 25 from the power cylinder 32 .

The input shaft 25 is a member constituting a connection path, and is connected to the front wheel steering mechanism B side via the operating shaft 23 and the connecting shaft 22af in addition to the rear wheel steering mechanism C. The auxiliary power is transmitted to both the front wheel steering mechanism B and the rear wheel steering mechanism C, and the steering operation of the steering wheel 20 for steering the front wheels 10 and the rear wheels 13 is performed by a single steering wheel for both the front and rear wheels. The steering wheel 20 can be easily operated even though the front wheels 10 and the rear wheels 13 are being steered.

In order to assist the steering wheels 20 in this way, a power cylinder 32 is placed at the front of the vehicle body, and the power cylinder 32 is connected to the connecting shaft 22.
Although this can also be achieved by connecting to the operating shaft 23, the illustrated passing power cylinder 32 is disposed at the rear of the vehicle body. This power cylinder arrangement position was chosen because there is more space left in the rear of the vehicle compared to the front where the engine 35 and other parts are located and space is limited, and the rear wheel steering mechanism C is Steered wheel 2 rather than front wheel steering mechanism B
0, it is necessary to increase the mechanical rigidity of the connection path for transmitting force to the power cylinder 32, which increases the vehicle weight. When placed on body ff1,
This problem does not occur because the weight of the vehicle can be reduced. As shown in FIG. 2, the power cylinder 32 is located behind the axle i4a of the knuckle arm 14 supporting the rear wheel 13, and the left and right rear wheel steering tie rods 18, 18. and a connecting rod 19 are arranged, and since this arrangement position is the position where the most space is left in the rear of the vehicle body, the space can be used effectively.

The internal left and right chambers s1.52Fi of the power cylinder 32 are connected to an oil tank (not shown) via a hydraulic circuit, and the hydraulic circuit selectively supplies hydraulic oil to the left and right chambers S□, S2 to control and operate the power cylinder 32. A valve has been intervened. The control valve constitutes a front self-power steering device together with the power cylinder 32, and the control valve also constitutes the steering wheel 20.
It also serves as a detection means for detecting the steering torque applied to the steering torque. In this embodiment, the control valve is the steering shaft 2 shown in FIG.
1 and is slidably housed inside the valve housing 36. Therefore, the power cylinder 32 and the control valve are mounted separately on the vehicle body.

The principle of switching operation of the control valve for selectively supplying hydraulic oil to the left and right chambers S, S2 is the same as that known in the power steering system of a vehicle that steers only the front wheels. That is, by making each tooth of the connecting rod 17a, which is a rack rod with which the pinion of the steering shaft 21 and the pinion engage, be helical teeth oblique to the axial direction, when the steering wheel 20 is rotated, The axial thrust generated by the helical teeth causes the control valve to slide within the valve housing 36. The control valve slides depending on the magnitude of the steering torque applied to the steered wheels 20, and is connected to the front wheel steering mechanism B from the power cylinder 32.

The magnitude of the auxiliary power transmitted to the rear wheel steering mechanism depends on the steering torque.

The steering wheel 20 and the front wheel 10 are connected to a steering shaft 21. Connecting rod 17a1
They are connected by a front wheel steering system consisting of a front wheel steering j-rod 16 and a knuckle arm 11, and the steered wheels 20 and rear wheels 13 are connected by a steering shaft 21, a connecting rod 17a1, a connecting path D1, a crank mechanism A, and a connecting rod 19. , rear wheel steering tie rod 18,
When connected by a rear wheel steering system consisting of a knuckle arm 14 and the front wheels 10 and rear wheels 13 are steered, the front wheels 10
The external force from the road surface acting on the rear wheels 13 is transmitted to the steered wheels 20 via the front wheel steering system, and the external force from the road surface acting on the rear wheels 13 is transmitted to the steered wheels 20 through the rear wheel steering mechanism. The magnitude of the steering torque required for this corresponds to the resultant force of these external forces.

However, since the control valve as the steering torque detection means is provided on the steering shaft 21 that constitutes the overlap path E, which is the confluence of the front wheel steering system and the rear wheel steering system, the external force acting on the front wheels and the rear wheel The control valve detects the resultant force of the auxiliary power generated in the power cylinder 32 for both the front wheels 10 and the rear wheels 13.

As shown in FIG. 3, the connection shaft 22a constituting the connection path Di is inclined in the upward direction when extracted, and the input shaft 25 is inclined in the upward direction.
38. By providing the universal joints 37 and 38 at both ends of the operating shaft 23 in this way, the operating shaft 23
There is no need to arrange the front wheel steering mechanism B1 and the rear wheel steering mechanism C at the same height level. Since the connecting path including the actuating shaft 23 is a bending path with two bends at the universal joint 37, 38, the actuating shaft 23 is extended below the floor component of the vehicle and placed outside the vehicle interior. This allows us to secure a large single room space, as well as assemble connecting routes,
It is possible to improve work such as assembly. Actuation axis 2
By providing universal joints 37 and 38'i at both ends of 3, it is possible to create a connecting route that avoids devices and equipment installed on the vehicle body, and also to prevent vibrations of the vehicle body while the vehicle is running. It also has the effect of absorbing the relative misalignment between the front and rear of the vehicle.

When connecting the connecting shaft 22a, the input shaft 25', and the operating shaft 23 with the universal joint 37, 38, the angle θ1 that the axis F of the connecting shaft 22a and the axis G of the input shaft 25 form with the axis H of the operating shaft 23. ．． By setting θ2 to be the same, the rotational angular velocity of the connecting shaft 22a caused by the front wheel steering operation of the front wheel steering mechanism A and the input shaft 25 that causes the rear wheel steering mechanism C to operate the rear wheel steering operation.
The rotational angular velocity can be made equal at all rotational angular positions.

As mentioned above, the operating shaft 23 is arranged outside the vehicle interior, and the connection path D
When the actuating shaft 23 is exposed outside the vehicle body, a cylindrical cover member 39 is placed over the outer periphery of the actuating shaft 23 to protect the entire length of the actuating shaft 23 from an adverse external environment such as pebbles and mud. The cover member 3
9 is attached to the lower surface of the floor component via a vibration absorbing member such as rubber. Moreover, a plurality of bearing bushes 40 for supporting the operating shaft 23 are fitted into the inside of the cover member 39, and the bushings 40 prevent the operating shaft 23 from whirling around, and the operating shaft 23 and the cover member It is possible to ensure that the actuating shaft 23 rotates in a state in which the axes of the actuating shaft 23 and 40 coincide with each other.

When the rear wheels 13 are steered by the crank motion of the crank mechanism A, the magnitude of the steering angle of the rear wheels 13 is determined by the distance traveled by the connecting rod 19 in the vehicle width direction, in other words, the fourth
It is determined by the eccentricity ε of the crank bin 27 from the input shaft 25 shown in the figure.

4 and 5 show a structure in which the eccentricity ε can be set to a desired value with a simple structure, and the crank pin 27 can be assembled to the input shaft 25 with a simple operation.

A holding member 42 is coupled to the rear end of the input shaft 25 with a bolt 41. The crank pin 27 is coupled to an arm member 43, and the arm member 43 includes a base portion 43a having a length in the axial direction of the input shaft 25, and an extending portion extending in the radial direction of the input shaft 25 from the rear end of the base portion 43a. 43b, and the crank pin 27 is connected to the extending portion 43b with a pin 44. A spacer member 45 whose thickness direction is in the radial direction of the input shaft 25 is applied to the lower surface of the holding member 42, and the lower surface of the spacer member 45 (L-shaped arm member 43
The spacer member 45 and the arm member 43 are connected and held by the holding member 42 using the bolt 46.

As a result, the bolt 46 can be tightened by the input shaft 25 by the work.
The crank pin 27 can be assembled to the
The value of the eccentricity ε can be determined depending on the thickness of the spacer member 45. By setting the thickness, the ratio of the steering angle of the rear wheels 13 to the steering angle of the front wheels 10 can be set to a value that is desirable for the vehicle to which the device according to the present invention is applied.

When the steering angle of the rear wheels 13 is zero, that is, when the vehicle is traveling straight, the crank pin 27 is located directly below the input shaft 25 as shown in FIGS. 4 and 5. A structure in which the relationship with the bin position can be achieved during the assembly work of the crank mechanism A is shown in FIG. The connecting rod 28 that connects the crank pin 27 and the connecting rod 19 is configured to be adjustable in length. Specifically, the connecting rod 28 is a threaded rod with right-handed and left-handed threaded portions 47a and 47b formed at both ends. 47, a long shaft-shaped nut member 48, 49 which is threadedly engaged with the threaded portions 47a and 47bK, and the threaded rod 47 and the nut member 48.
It is a turnbuckle type consisting of lock nuts 50 and 51 which are tightened and connected with 49. Rocknut 50.
When loosening 51v and rotating screw rod 47, connecting rod 2
8 can be changed in length, thereby connecting the crank pin 27 positioned directly below the input shaft 25 and the connecting rod 19 so that the steering angle of the rear wheels 10 is zero when the steering angle of the front wheels 10 is zero. Next, the structure for assembling the connecting rod 19, the power cylinder 32, etc. to the vehicle body will be described. FIG. 7 is a sectional view taken along line 7-7 in FIG. 2, showing the structure. Connecting rod 19, power cylinder 32
A beam-shaped support member 52 is provided below to extend across the width of the vehicle body, and as shown in FIG. The first arm part 53id has one arm approximately at the center in the length direction of the support member 52, and the second arm part 54 has two arm parts at both ends in the length direction. Cylindrical members 53a and 54a are fixed to the tops of the respective arm portions 53 and 54, and the cylinder members 53a are connected to the vehicle body. The cylindrical member 54a is the lower arm 15 for the rear wheel.
The inner end portion 15ai of the vehicle body is sandwiched between the mounting boss portion (not shown) provided on the vehicle body, and the second section of the lower arm inner end portion 15a and the cylindrical member 54a is schematically illustrated by a chain line 55. The shaft provided in the lower arm 15 is inserted, and the support member 52 is thereby connected to the vehicle body at three locations, and the support member 52 is utilized to support the lower arm 15. Vibration absorbing members 53b and 54b made of rubber or the like are fitted inside the cylindrical members 53a and 54a to prevent vibrations from propagating between the support member 52 and the vehicle body.

As shown in FIG. 7, a third arm portion 56 extending forward is coupled to the support member 52, and is assembled and integrated with the main body case 34 of the power cylinder 32 to the arm portion 56, and the piston rod 33 of the power cylinder 32. Case 2 with inserted
4 is placed on the arm portion 5, and the fastening member 57 is secured to the arm portion 5 with the bolt 58.
6, the power cylinder 32 is attached to the support member 52. Such a power cylinder 32
There are two mounting parts as shown in Figure 2. As shown in FIG. 7, a fourth arm portion 60 is coupled to the support member 52, which extends rearward and upward and has a half-shaped receiver 59 at the top, and the receiver is attached to the upper surface of the member 59 as shown in FIG. Vibration absorbing member 6 on the outer peripheral surface
1. A cylindrical member 63 having bearings 62 on its inner peripheral surface is mounted, and the receiver is a half-shaped fastening member 64 symmetrical to the member 59.
By connecting the receiver to the member 59 with bolts 65 as shown in FIG. 7, the connecting rod 19, which is slidably supported on the bearing 62 as shown in FIG. 6, is supported by the support member 52. The supporting portions of the connecting rod 19 are also provided at two locations as shown in FIGS. 2 and 6.

As is clear from the above, the support member 52 connected to the vehicle body has the function of supporting three types of members, the rear wheel lower arm 15, the power cylinder 32, and the connecting rod 19, to the vehicle body, and makes effective use of space at the rear of the vehicle body. These members can be assembled to the vehicle body using a structure with a small number of parts.

As shown in FIG. 6, the connecting rod 19 is constructed by fitting and connecting the opposing ends of left and right rod halves 66 and 67, and the connecting rod 19
6.67 outer end (integrally provided ball part 66a,
The ball receiver 67a is incorporated into the inner end of the left and right rear wheel steering tie rods 18.18, and the members 68.69 slidably surround the connecting rod 19 and the tie rod 18.18.
18, thereby allowing movement of the tie rod 18 for steering the rear wheels 13 as the connection rod 19 moves in the vehicle width direction. The bearing 62 that supports the connecting rod 19 is composed of an inch member 62a on the inner circumferential side and an outer member 62b on the outer circumferential side, and the contact surface between the inner member 62a and the outer member 62b is a spherical surface curved and bulged in the outer circumferential direction. Therefore, the bearing 62 is a spherical bearing with self-aligning action. Therefore, when the connecting rod 19 moves in the width direction of the vehicle body while being supported by the bearing 62, the movement has a slight angle of inclination with respect to the width direction or the vertical direction of the vehicle body.
Even if the movement is performed at a certain angle, it is possible to prevent sliding resistance from occurring between the bearing 62 and the connecting rod 19, and to ensure smooth movement of the connecting rod 19.

Connecting rod 28 and connecting rod 19 via the connecting pin 29
The connection with the ball part 29ai of the connecting pin 29 is the connecting rod 1.
Since the ball receiver 9 is slidably supported by the member 31, the connection between the crank pin 27 and the connecting rod 28 and the connection between the connecting rod 19 and the rear wheel steering tie rod 18 are performed using a ball joint. However, the center 2 of the ball portion 29a is located on the axial center line J of the connecting rod 19. According to this structure, when the connecting rod 19 is moved by the tensile force and compressive force in the vehicle width direction of the connecting rod 28 due to the crank movement of the crank mechanism A, the action of the axial center line J of the connecting rod 19 and the tension force Since there is no positional deviation or offset between the points, the swinging of the connecting rod 19 can be prevented, and the connecting rod 19 can be made to perform a predetermined linear movement.

As is clear from the above description, according to the present invention, an input shaft that rotates in conjunction with a steered wheel, a crank pin eccentrically connected to the input shaft, and a tie rod for steering the left and right rear wheels are connected to the crank pin. The entire crank mechanism consists of a connecting rod that connects the connecting rod, the connecting rod and the connecting rod are connected by a ball joint, and the center of the ball part of the ball joint is located on the axis center line of the connecting rod. , there is no positional deviation between the application point of the tensile and compressive force as the operating force of the connecting rod due to the crank movement of the crank mechanism and the axial center line of the connecting rod, so that the rocking of the connecting rod occurs and the rear wheel is moved noisily. It becomes possible to achieve the linear movement of the connecting rod in the width direction of the vehicle body, which is necessary for steering.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and Fig. 1 is an overall plan view of the vehicle showing the main members and structure in solid lines, and Fig. 2 is a partially enlarged view of Fig. 1 showing the rear part of the vehicle body. , FIG. 3 is a side view showing a connection path connecting the front wheel steering mechanism and the rear wheel steering mechanism, FIG. 4 is a partially enlarged side sectional view of FIG. 3, and FIG.
A composite view of half-cut cross-sectional views taken along lines 5A-5A and 5B-5B in the figure. Figure 6 is a plan cross-sectional view of the vicinity of the power 4 cylinders, crank mechanism, and rear wheel steering mechanism located at the rear of the vehicle body.
FIG. 7 is a sectional view taken along line 7-7 in FIG. In the drawing, 10 is a front wheel, 13 is a rear wheel, 18 is a tie rod for rear wheel steering, 19 is a connecting rod, 20 is a steering wheel, 25 is an input shaft, 27 is a crank pin, 28 is a connecting rod, 29a
is the ball part, A is the crank mechanism, B is the front wheel steering mechanism, C
is the rear wheel steering mechanism, D is the connection path, ■ is the center of the ball part,
J is the axial center line of the connecting rod. Patent Applicant Honda Motor Co., Ltd. Representative Patent Attorney Yoshi Shimoda Patent Attorney Kunihiko Ohashi No. 3 〃 Figure χ 4U Written amendment of faithful procedure (voluntary) 1. Indication of the case Japanese Patent Application No. 120420/1982 2, Name of the invention Vehicle steering device 3, Person making the amendment Relationship to the case Patent applicant (532) Honda Motor Co., Ltd. 4, Agent (1) Specification No. The second line of page 3 says "on the axis center line".
0 (2. The scope of the claims is amended as shown in the attached sheet. [2. Claims of a vehicle] In the steering device, a connecting rod connects a crank pin eccentrically in the radial direction of the input shaft to an input shaft that rotates in conjunction with a steered wheel, and connects the crank pin to a tie rod for steering left and right rear wheels. A steering system for a vehicle, characterized in that the connecting rod and the connecting rod are connected by a connecting rod, and the connecting portion between the connecting rod and the connecting rod is a ball joint in which the center of the ball portion is located approximately on the axial center line of the connecting rod.

Claims (1)

[Claims] In a vehicle steering system in which front wheels and rear wheels are steered by steering operation of a steering wheel, a crank pin is attached to an input shaft that rotates in conjunction with the steering wheel, and is eccentrically arranged in the radial direction of the input shaft. and connect the crank pin and a connecting rod that connects the left and right rear wheel steering tie rods with a connecting rod, and align the connecting portion between the connecting rod and the connecting rod so that the center of the pole is on the axis center line of the connecting rod. A vehicle steering device characterized by having a ball joint.