JPS5959571A - Rack/pinion steering system - Google Patents

Abstract

PURPOSE:To improve steering feeling and durability by employing arched cross- section for the sliding face between rack and pinion while forming a stopping section on the rack and providing an idle clearance around the axis of rack against the rack guide. CONSTITUTION:A rack 22 is formed to have arched cross-section while a stopping section 22b is projected from the central portion of the sliding face at the opposite side of the rack teeth 22a. A receiving groove 25a for fitting said section 22b is made in a recess F3 forming the arched sliding face of a rack guide 25 while an idle clearance C1 is formed between the stopping section 22b and receiving groove 25a. Since the rack 22 can rotate in the range of said clearance, rotary motion of rack 22 based on the working error of teeth can be absorbed to provide smooth steering feeling and to improve durability.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rack and pinion type steering device, and in particular, by improving the axial cross-sectional shape of the rank, the rack is given several degrees of freedom of slight rotation around the axis, thereby achieving good steering. It is intended to give a sense of well-being and a high degree of permanence.

The conventional rack and pinion steering device is shown in Figure 1 or Figure 2.
It has the configuration shown in the figure. First, referring to FIG. 1, a lip carpinion (3) at the tip of an input shaft that is linked to a steering wheel (not shown) is rotatably supported in a cylinder (1) of a rack and pinion type steering device.
This pinion (3) is connected to the rack teeth (2aX) of the rack (2).
R meshing allows the rack (2) to reciprocate in the axial direction. A cylinder part (4) is connected to the nozzle lug (1) at a position opposite to the meshing part between the two rack teeth (2a) and the pinion (3). A biasing spring (7) is provided between the rack guide (5) and the retainer (6) which is screwed into the open end of the cylinder portion (4) and the rack guide (5). ) is inserted and the rack (2) is added to the pinion (3) along with the rack guide (5). In addition, (8) is a lock nut of the retainer (6), and the above-mentioned force can be adjusted.

Therefore, the rack kite (5), which is composed of the rear surface of the rack (2), that is, the sliding surface with the rack guide (5) + d round bar with an arcuate cross section, and still supports the rack (2).
) is also configured as a concave portion (F□) with an arcuate cross section. According to these sliding surfaces, rank (2)
) is arranged in a dramatic alternation with the helical pinion (3), so the lateral component of the engagement force between these two forces the rack (2) to rotate around its axis. It is possible to absorb this by the relative rotation of the two kizuri joints.

By the way, is it possible to guarantee the degree of rotational freedom of the rack (2) in this way by ensuring smooth engagement between the rack (2) and the pinion (3)? Since the rotational force in the upper and periphery directions is concentrated on both ends (2a') and (2a') of the rack tooth (2a) in the 1J direction, if an impact force is repeatedly applied to the rack, especially when driving on dead ground, the tooth part It had the disadvantage of causing fatigue over time and significant strength deterioration.

For this reason, a configuration means as shown in FIG. 2 has already been proposed in order to constrain the rotational degree of freedom. That is, the rack (12) is configured as an inverted triangular cross section, and the triangular apex fits into the rack guy)' (15) (formed as the sliding surface of R11 (ri slope groove part (F2). According to this configuration , rack (one rotation is the slope groove part (F,)
The above-mentioned impact force exerted between the rack (12) and the pinion (3) is prevented by the planar contact at (
However, the accuracy of the meshing part 'W FJ!
Strict restrictions will be required. I mean,
Even a slight machining error in the teeth J cedar makes it impossible to expect a smooth engagement process, which adversely affects the steering feel.

Since the pressure receiving area of the rack guide 05) is reduced compared to the arcuate cross section shown in Figure 1, the pressure of the pressure receiving part (bi pressure) rises northward, and the wear of the sliding contact surfaces increases accordingly. rack guide 0
As for 5), it also had the disadvantage of causing damage to personnel.

In view of the slope, the present invention attempts to improve the steering feeling by allowing only a small degree of rotational freedom of the rack, and to ensure the strength of the rack by alleviating the impact force applied to the southern part. The cross-sectional shape of the sliding surface between the rack and the rack guide is an arcuate cross-section, and the rack is provided with a protruding locking portion, and between the locking portion and the rack guide there is a cross-sectional shape around the rank axis. It is characterized by the presence of floating clearance.

Hereinafter, the present invention will be explained with reference to the embodiments shown in FIGS. 6 and 4, in which parts that are the same as those in the conventional example are designated by the same reference numerals. is formed as a circular arc, and its rack teeth (22a,
) The locking part (22'b) is attached to the sliding contact surface of the medium heat part on the opposite side of 1111.
is protruded, and a receiving groove (25a) into which the rack guide (row) is inserted is bored. A floating clearance (C) of the locking portion (22b) is interposed between the two and the locking portion (22b). It is desirable that

According to the above configuration, since rotation of the rack (22) is allowed within the range of the free movement clearance (C□), the rotational movement of the rack (22) based on machining errors in the tooth profile is absorbed, resulting in a smooth steering feel. At the same time, the requirement for tooth profile accuracy can be relaxed. Then, use a rack (the rotation of the pot is as shown in Fig. 5 (
As shown in b), the locking part (221)) is inserted into the receiving groove (2S
a) Rotation angle δ, which corresponds to the free movement clearance (C3) on the wall surface. It can be stopped by touching it with
Even if impact force is applied to the above-mentioned meshing part due to driving on rough terrain, etc.,
This is received by the locking part (22b), and no further rotational force is applied to the tooth part, the strength of the tooth part is not impaired, and the design freedom IW of gear specifications can be increased. can. Moreover, since the back pressure of the rack (22) due to meshing is received by the wide sliding surface with an arcuate cross section, the surface pressure applied to the rack guide (25) is relatively small, and the rack guide (A) Can last 11 years against wear.

Note that the cross-sectional shape of the locking portion (22'b) is not limited to that shown in the drawings, and various shapes such as an arc shape can be selected.

Next, FIG. 4 1 shows another embodiment of the present invention, in which the sliding surface of the rack (the acupuncture needle is formed as an arcuate cross section and the rack guide C, 35 which slides and guides the needle) is also similar. It is configured as an arc-shaped concave part (F4), and on the outside of this sliding surface, there are two holes on both sides of the rack arm.
A floating clearance (C2) is interposed between the rack guide ja5) and the top surface (filter 5a) of the locking portion (321:l).
) is installed protrudingly. Therefore, in this embodiment as well, the rotation of the rack (32) is as shown in FIG.
The locking portion (32b) comes into contact with the top surface (filter 5a) of the rank guide t35), and the subsequent rotation is prevented from rotating within the range of FIG. It is clear that the same effect can be expected.

In this embodiment, the locking portion (32T-
+) can be formed at the same time as the surplus metal flowing portion generated during the plastic working of the tooth portion in the rack country, and there is an advantage that the portion that was conventionally cut and discarded can be effectively utilized.

As described above, according to the present invention, it is possible to provide a rack and pinion type steering device that has good steering feel, high strength, and durability.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional rack and pinion steering device 4.
FIG. 2 is a sectional view showing the main parts of another conventional modification, and FIG.
Cross-sectional view of +11 and its operation explanation diagram, Fig. 4(a),
(b) is a sectional view showing the main parts of another embodiment of the present invention and an explanatory view of its operation. (1)--Housing (2), (+2+, (next), (23+...Rank (a) --Hinion (4)e-Cylinder part (
51, (15), (25), f35)...Rack guide (6)...Retainer (7)...Biasing spring (22'b), (32'l))...Locking part Fig. 1 Figure 2 Figure 3 Figure 4 Hand, Reading Correction (self-initiated) 1. 1. Cow display. 1984 Patent Application No. 170076. 2. Name of the invention. Rank and pinion type steering gear. 3. Correction with the moss incident that makes noise. Relationship between the 4th generation patent applicant and the 1st person 5, the scope of claims of the specification subject to amendment, and the bridge of the detailed description of the invention. 6. Contents of the amendment (1) The scope of the claims of the document is amended as shown in the attached sheet. (2) The statement ``opulent effort'' on page 4, line 6 of the Meisho book was changed to ``
vi zero ka,” he corrected. rllll,! -IE Hi('s T41: i'l' RJ
,>K's #fg il month t 8ki 4 Shimata-^
(1) A binion supported by one width on both the rotation and transmission sides in the housing, and a pinion that can be freely rotated in the 1111 direction on the JZ in≦casing (l is provided and the upper ML l binion is connected to the upper ML l binion: Rack and '7i' in two gl housings? rJj
＋ The cylinder that was rotated automatically slid into the IS circle, :L,,
J2h-l love between pinion and rack and anti-x': Jv
nl sword 1 and the rack are equipped with a rack guide and this rack kite is written on the cylinder 1) Tsukiguchi Masa β hllY
! It is a common sentence with a tailor ((1) and it sentence (also,
1] 7t rack and pinion type rudder ray with suspension springs
= j, the sliding surface of the rank and the rack guide is formed into a five-claw cross-sectional shape, and the rank (
)(, system city 11) hit 3, sink, this locking 111S and rank tunoid)ijl It colzJ, rack'
Rack and pinion steering table 1 (j
,'. (2) Install a locking part A on the rack 1) III, and connect this lock IXb to the thick guide Ill level J.
The entire feature is that the floating clearance is valved and inserted into the hollowed out fin part.
7, -> Rack and pinion steering system described in item 1. (3) A locking part is provided on each side of the rack, and these locking parts are installed on both sides of the rack. ii'
The rack and pinion steering system according to claim #61.

Claims (1)

[Claims] (],) A pinion rotatably supported in the housing;
A rack is provided on the cane lug so as to be slidable in the axial direction and meshed with the pinion, and the rack is slidably fitted into a cylinder portion formed in the housing, and the meshing portion between the pinion and the rack and the reflective side are provided. In a rack and pinion type steering device, the rack and pinion steering device includes a rack guide that is in sliding contact with the rank, and a biasing spring that is elastically supported between the rack guide and the retainer that is fastened to the cylinder opening. The sliding contact surface with the rank guide is formed into an arc shape, and a locking part is provided protrudingly on the rack, and free clearance teeth around the rack axis are interposed between the locking part and the rack guide. A rack and pinion type steering device. (2) A locking part is provided protrudingly on the sliding contact surface on the rack side, and the locking part is fitted into a groove formed in the bolt joint of the rack guide 11III through a free movement clearance. The rank and pinion type steering device according to scope 1. (3) Rack teeth (a locking part is provided protrudingly on each part 111,
Claim 1 characterized in that a free movement clearance is provided between these locking portions and the top surface of the rack guide.
The rack and pinion steering device described in .