JPS619378A - Steering gear for front/rear wheels - Google Patents

Abstract

PURPOSE:To solve a problem on backlash over the whole circumference of an internal gear in an automatic manner, by constituting the internal gear with two ring gears superposed, while installing a preload device energizing one side ring gear to its rotational direction. CONSTITUTION:An internal ring gear 70 revolving as engaged with a pinion 31 is installed in the recess of a box 51 upon thrust regulation with a snap ring 79. This ring gear 70 consists of two ring gears 71 and 72 superposed in the axial direction, and one side gear 71 is unrotationally locked to the box 51 with a bolt 78, while both upper and lower stepped parts 73 and 73 are formed in one side of the other gear 72, and adjusting bolts 77 and 77 being screwed in the box 51 from both vertical directions are applied to these stepped parts 73 and 73.

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 developed a special steering system as one of the so-called asymmetric function type steering systems, in which the maximum steering angle is larger when the rear wheels are out of phase with the front wheels than when they are in the same phase. Gansho 58-2
No. 37323 was proposed. In this steering system, a cylindrical member integrally equipped with a pinion and an eccentric cam is rotatably fitted to an eccentric shaft installed at the rear end of the input shaft of the rear wheel steering system, which rotates in conjunction with the steering wheel. At the same time, the pinion is engaged with an internal gear fixed to the vehicle body, and a joint member that connects and supports the left and right rear wheel tie rods is rotatably fitted to the eccentric cam, and this joint member is connected to the vehicle body via a link mechanism. The swing of the joint member is restricted by supporting the joint member.

Furthermore, we have also proposed a structure in which the backlash with the pinion can be adjusted using an eccentric bolt inserted into the holder of the internal gear (Jt).

(Problem to be solved by the invention) However, although it is true that the latter structure allows for adjustment of gear meshing, strictly speaking, the backlash adjustment is only at one location on the eccentric bolt, and the entire circumference of the internal gear is adjusted. It was impossible to adjust the backlash.

The present invention was made to solve such technical problems,
The object of the first invention, which is the specific invention, is to provide front and rear wheel steering that can automatically eliminate the backlash between the pinion and the internal gear over the entire circumference of the internal gear, and achieve silent gear meshing. We are in the process of providing equipment.

The second invention, which has the first invention as its main part, further aims to provide a front and rear wheel steering device that can reliably perform fine adjustment of backlash around the entire circumference of the internal gear.

(Means for Solving the Problems) Accordingly, in the first aspect of the present invention, an eccentric shaft (22) is provided at the rear end of an input shaft (20) of a rear wheel steering system that rotates in conjunction with a steering wheel. , pin-on (31) and eccentric cam (32)
) is rotatably fitted into the cylindrical member (30) integrally equipped with a fixed-side internal gear (70) that meshes with the pinion (31), and a tie rod for the left and right rear wheels (
15), a joint member (4) that connects and supports (15).
0) is engaged with an eccentric cam (32). It is characterized in that it is constructed of stacked layers and is provided with a preload means for biasing the rotatable ring gear (72) in the rotation direction.

Specifically, the preload means includes two ring gears (71
), a plurality of four parts (74) in the circumferential direction provided in (72)...
・S-shaped springs (75) each compressed inside...
It is.

Furthermore, in a second invention, in addition to the configuration of the first invention, an adjusting means is provided for regulating the rotational position of the ring gear (72) which can rotate once and adjusting the amount of preload of the preload means (75). It is characterized by

Specifically, the adjustment means includes an internal gear (70
) Bolts (77), (77) that come into contact with steps (73), (73) provided on a ring gear (72) that is rotatable by being screwed into a holder (50).

(Function) In this way, the non-rotatable ring gear (71) and the rotatable ring gear (72) are overlapped to form the internal gear (70).
), and is provided with a preload means (75) that biases the rotatable ring gear (72) in the rotational direction, so the pinion (31) is It is possible to preload the internal gear (70) so as to sandwich the internal gear (70), thereby realizing silent gear meshing over the entire circumference of the internal gear (70).

Furthermore, since adjustment means (7?) and (77) are provided to restrict the rotational position of the rotatable ring gear (72), the amount of preload of the preload means (75) can be adjusted to achieve fine adjustment of backlash. can.

(Embodiment) A preferred embodiment of the present invention will be described below in detail based on the attached drawings.

FIG. 1 is a cross-sectional view of a steering angle function generating mechanism of a rear wheel steering system showing the main part of the present invention, FIG. 2 is a view taken along the line II-Il, and FIG. 3 is a view taken along the The sectional view and FIG. 6 are schematic perspective views of the entire steering device.

As shown in Figure 6, 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 (4). Knuckle arms (6), ([i) supporting the front wheels (?), (?) are connected to the tie rods (5), (5),
As is known, the front wheels (7), (7) are steered in the steering direction of the steering wheel (1).

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 (lO).
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 eccentric shaft (22) is provided to protrude from this flange (21). The base of this eccentric shaft (22) is formed into an acid tapered portion (23).

The eccentric shaft (22)l has a pinion (31) at the front.
A cylindrical member (30) integrally equipped with a circular eccentric cam (32) at the rear thereof is rotatably fitted thereinto. That is, the inner periphery of the pinion (31) of the cylindrical member (30) is formed into an acid tapered portion (33),
A pole (24) between the acid taper part (23)...
In addition to constructing an angular bearing by interposing
A roller (25) is interposed between the inner periphery of the eccentric cam (32) and the tip of the eccentric shaft (22).

On the other hand, as shown in Fig. 6, the tie rods (15) and (15) connected to the knuckle arms (+s) and (1B) supporting the rear wheels (17) and (1?) are ball joints (14) and (
14), and is connected and supported to both ends of the joint shaft (30). As shown in FIG. 1, a fixed member (41) is provided at the center of the joint shaft (40). That is, the engaged member (41) is connected to the cylindrical portion (42) by the two bolts (49), (4
At step 9), it is fixed and integrated in the center of the upper joint shaft (40),
Acid tapered surfaces (44), (44) facing forward are formed on opposing surfaces of two left and right vertical wall portions (13), (43) projecting forward of the joint shaft (40).

And the pole (35)...
The engaging member (36) is installed with the eccentric cam (32
) is equipped with a contact type angular bearing. The left and right vertical walls (3?) of this engaging member (36), (3
? ) male tapered surface facing rearward (38), (3
8). These two male tapered surfaces (3B), (38
) has a stopper protrusion (3θ) at the lower end of the (3
9), (313), and (39) are projected.

Furthermore, when the engaging member (36) and the engaged member (41) are assembled together, both the left and right tapered surfaces (38), (4
4), (3B), and (44), as shown in FIG. ... respectively.

The above input shaft (20) and joint shaft (40) are connected to a box (51) at the center and pipes (52) at the front and left and right sides.
), (53), and (53) are supported by a holder (50) integrally formed therein. That is, with the engaged member (41) facing inside the box (51) of the holder (50), the joint shaft (40) is inserted into the left and right pipes (53), and the metal bearing (54) inside the (53).

(54), it is pivoted so as to be horizontally slidable left and right. Then, with the eccentric shaft (22) facing inside the box (51), the engaging member (36) is attached to the member to be secured (41) with the roller (46).
..., (4B)... to rotatably support the input shaft (20) in the front pipe (80).

Furthermore, an internal ring gear (70) in which the pinion (3) meshes and revolves is provided in the inner part of the poncus (51) when viewed from the rear, and the thrust is restricted by a snap ring (78).This ring gear (70) consists of two ring gears (71) 4 (72) stacked in the axial direction, one gear (71) is connected to the box (51) (78).
), and on the side of the other gear (72) are formed lower step portions (73), (73), which are screwed together from the top and bottom of the box (51). Pol) (??)
, (??) to the stepped portions (73) and (7,3). Also Ryousungukya (71).

(72) is provided with a large number (six in Fig. 2) of four parts (74)... which penetrate in the axial direction.
), an S-shaped spring (75) as shown in FIG. 3 is compressed in the circumferential direction to preload the gear (72) on the rotatable side.

Specifically, the input shaft (20) is supported by installing a ring (27) on the front part of the flange (21) at the rear end with a pole (26) interposed therebetween, and using a contact type angular bearing. The ring (27) is lightly fitted to the inner periphery of the base end of the pipe (52). Then, apply the thrust washer (61) to the front end of the ring (27), screw the sleeve (60) into the pipe (52), and insert the sleeve (6o).
Abut the rear end against the washer (61). Sleeve (6o
) and the input shaft (20), a coil spring (82) is inserted into this space, and the seat (84) is regulated by a step (63) at the middle part of the inner circumference of the sleeve (6o). A spring (82) is compressed between the washers (61) and preloaded to bias the ring (27) rearward.

Furthermore, a lock nut (65) is screwed onto the sleeve (60). Also, the front end of the sleeve (60) and the input shaft (20)
A roller bearing (66) is interposed between them, and a seal cap (67) is placed thereon.

By the way, as shown in FIG. 5, a vertical surface (47) is formed on the rear surface of the member to be secured (41), and the box (51)
A boss (56) is formed on the opposite surface of the force bar (55) to tighten and close the opening (59).
A guide groove (57) is formed in the left-right direction in the groove (56), and a vertical surface (57) facing the vertical surface (47) is formed in this groove (57).
81) is inserted. At the left and right ends of this vertical surface (81), there are stopper protrusions (82),
(82) is projected. The guide bar (80) is screwed into the cover (55) from the rear with two wooden poles on the left and right) (
83) and (83) to keep it biased forward and hold it against the rain vertical surface (
A roller (85) whose axis is perpendicular and which is held by a retainer (84) is interposed between 47) and (81). Further, a plate spring (86) is interposed between the guide bar (80) and the cover (55) to preload the guide bar (80) so as to always urge it forward.

Thus 1. Align the input shaft (20) with the left and right center line -L of the vehicle body, arrange the Holter (page 50), and connect the left and right pipes (53).
), (53) with soft mounting rubber (91), (91
) are interposed and supported by the vehicle body side brackets) (92) and (92). In addition, the left and right ball joints (14) are tightened with bands to one end of the pipe (53) and one end of the tie rod (15), respectively.
94), covered with (94).

In the above steering system settings, the eccentric shaft (22) is connected to the input shaft (2
0), the vertical direction 1 is initially set vertically downward as shown in Figure 4, and when the front wheels (?) and (7) are steered to the right, the eccentric shaft (22) is rotated clockwise in Figure 4. Set the crank to rotate. Here, the pinion (31) meshes with the lowest part of the ring gear (70) as shown in FIG. 2, and the top (34) of the eccentric cam (32) faces vertically downward as shown in FIG.

First, the rotation direction of the pinion (31) due to crank rotation from the initial position of the eccentric shaft (22) is opposite to the rotation direction of the eccentric shaft (22) when the revolution angle is less than a predetermined angle. Since the horizontal movement directions of the eccentric shaft (22) and the rear portion (34) of the eccentric cam (32) are opposite to each other, the resultant displacement amount, which is the difference between them, is small.

Therefore, the joint shaft (40) that engages with the eccentric cam (32)
) because the maximum left-right displacement of the rear wheel (17) is small.

The maximum steering angle when (17) is steered in the same direction as the front wheels (7) and (?) is small.

Furthermore, if the revolution angle of the pinion (31) exceeds a predetermined angle,
An eccentric shaft (22) and an eccentric cam (3) relative to the input shaft (20)
2), the direction of movement to the left and right is the same as that of the top (34) of The maximum steering angle of the wheels (17), (17) in the direction opposite to that of the front wheels (7), (?) increases.

In the above, the internal ring gear (70), which the pinion (31) meshes with and revolves around, is composed of a non-rotatable gear (72) and a rotatable gear (72), and the rotatable ring gear (72) is preloaded with an S-shaped spring (75) that urges it in the rotational direction, so its elastic force moves the pinion (31) between the two ring gears (71), (
72) It is possible to apply preload so that the entire circumference is always sandwiched in between. Therefore, backlash around the entire circumference of the internal gear (70) can be automatically eliminated, and gear meshing can be made silent.

Furthermore, since adjustment bolts (77) and (??) are provided, the set preload amount of the S-shaped spring (75) can be adjusted by adjusting the rotation of the rotatable ring gear (72) and regulating its position. Since it can be adjusted, fine adjustment of backlash can be reliably performed around the entire circumference of the internal gear (70).

(Effects of the Invention) According to the front and rear wheel steering device of the first invention as shown below,
In particular, the internal gear is constructed by stacking two ring gears, and a preload means is provided to bias one of the ring gears in the rotating direction, so that the pinion of the eccentric shaft -L can be preloaded so as to be sandwiched between the two ring gears. , it is possible to automatically eliminate the discrepancy around the entire circumference of the internal gear, and it is possible to achieve silent gear meshing.

Furthermore, in the second invention, since an adjusting means is provided for regulating the rotational position of one of the ring gears biased in the rotational direction by the preloading means, the backlash can be finely adjusted by adjusting the preload amount of the preloading means. It can be performed.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the steering angle amount dispersion generating mechanism of the rear wheel steering system showing the main part of the present invention, Fig. 2 is a view taken along the line TI-Il in Fig. 1, and Fig. 3 is Fig. 2 Cross-sectional view along line m-m, Figure 4 is Figure 1 I
5 is a sectional view taken along line V-TV in FIG. 1, and FIG. 6 is a schematic perspective view of the entire steering system. 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, (30)
is a cylindrical member, (31) is a binion, (32) is an eccentric cam,
(40) is a joint member, (50) is a holder, (70)
) is an internal gear, (71) and (72) are ring gears, (73) is a stepped part, (74) is a four part, (75) is an S-shaped spring, and (77) is an adjustment bolt. Patent applicant: Agent for Honda Motor Co., Ltd.
Patent Attorney Part 2 1) Part 1 Patent Attorney
Kuni Ohashi, Patent Attorney Koyama
〉] 8-, ω of n agreement column 8

Claims (4)

[Claims] (1) A cylindrical member integrally equipped with a pinion and an eccentric cam is rotatably fitted to an eccentric shaft provided at the rear end of an input shaft of a rear wheel steering system that rotates in conjunction with a steering wheel, and the pinion A vehicle is provided with a fixed-side internal gear that meshes with the eccentric cam, and a joint member that connects and supports left and right rear wheel tie rods is engaged with the eccentric cam, so that the rear wheels as well as the front wheels are steered by steering operation of the steering wheel. In the steering device, the internal gear is constructed of a two-layer structure of a non-rotatable ring gear and a rotatable ring gear, and a preload means is provided for biasing the rotatable ring gear in the rotational direction. A front and rear wheel steering device characterized by: (2) In claim 1, the preload means is an S-shaped spring compressed into a plurality of recesses in the circumferential direction provided in two ring gears forming the internal gear for the front and rear wheels. steering gear. (3) A cylindrical member integrally equipped with a piston and an eccentric cam is rotatably fitted to 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 A fixed-side internal gear that meshes with the pinion is provided, and a joint member that connects and supports left and right rear wheel tie rods is engaged with the eccentric cam, so that the rear wheels are steered along with the front wheels by steering operation of the handle. In the steering device for a vehicle, the internal gear is constructed of a two-layer structure of a non-rotatable ring gear and a rotatable ring gear, and a preload means for biasing the rotatable ring gear in a rotational direction. A steering device for front and rear wheels, further comprising adjusting means for regulating the rotational position of the rotatable ring gear and adjusting the amount of preload of the preloading means. (4) In claim 3, the preload means is an S-shaped spring compressed into a plurality of recesses in the circumferential direction provided in two ring gears forming the internal gear, and The adjustment means is a front and rear wheel steering device, which is a bolt that is screwed into the holder of the internal gear and abuts on a step provided on the rotatable ring gear.