JPS6123969Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rack guide device that is used in a rack-and-pinion type steering device and maintains appropriate backlash between the rack and pinion, and in particular, the invention relates to a rack guide device that is used in a rack-and-pinion type steering device and maintains appropriate backlash between the rack and pinion. This invention relates to a rack guide device suitable for preventing contact.

Conventionally, in rack-and-pinion steering devices for automobiles, as shown in FIGS. 1 and 2, a housing 3 is slidably fitted onto the back surface of a portion of a rack 1 that engages with a pinion 2. A rack guide 4 is disposed, and a spring 6 is elastically supported on a screw member 5 mounted on the housing 3, and the spring 6 presses the rack guide 4 against the rack 1, whereby the rack 1 and pinion 2 are brought into contact with each other. Generally, a rack guide device is used which maintains an appropriate amount of backlash between the tooth surfaces.

By the way, in this type of rack guide device, as shown in the figure, the rack guide 4 is simply slidably fitted into the housing 3 and pressed against the rack 1 by the spring 6, so that the rack 1 is not subject to sudden speed changes. In some cases, especially when the direction of movement is reversed, the manner of contact with the rack guide 4 becomes unstable, resulting in uneven contact, which increases the sliding resistance of the sliding portion.

The present invention was devised to solve these conventional problems, and its purpose is to provide a rack guide device that can prevent uneven contact on the sliding surface of the rack guide and significantly reduce sliding resistance. It's about doing.

In view of the above points, in the present invention, a rack guide that slides into contact with the rack is fitted into the opening of the housing on the back side of the meshing part of the rack with the pinion, and the rack guide presses the rack toward the pinion. In the rack guide device, the rack guide and the support member supporting it are brought into contact with each other by a convex portion formed on one of them and a concave portion formed on the other, and these convex portions and concave portions are brought into contact with each other. The rack guide is swingably supported on the support member by making contact only at the top in a direction perpendicular to the axial direction of the rack, and using the top as a fulcrum with a swing gap interposed between the convex part and the recess. , and a gap is formed between the rack guide and the opening in which the rack guide is fitted to allow the swing of the rack guide, thereby preventing uneven contact of the sliding surface of the rack guide with the rack. It is characterized by

The present invention will be explained below with reference to the drawings.

3 and 4 show a first embodiment of the present invention, in which 11 is a rack and 13 is a housing. A rack guide 14 is inserted into the housing 13 from the open end side thereof, and the rack guide 14 is inserted into the housing 13.
The screw member 15 is screwed into the open end of the screw member 15 to prevent it from coming off. Further, a spring 16 is interposed between the rack guide 14 and the screw member 15.
The rack guide 14 is pressed against the rack 11 with a constant pressure by the biasing force of the spring 16.

3 and 4 between the circumferential surface of the rack guide 14 and the inner circumferential surface of the housing 13.
As shown in the figure, a certain gap G is provided,
Further, a conical recess 17 is provided in the center of the surface of the rack guide 14 facing the screw member 15. In this recess 17, there are
As shown in the figure, a convex portion 18 protruding from the center of the surface of the screw member 15 facing the rack guide 14 and having a conical tip is in contact with the screw member 15. and,
The angle θ ₁ of the conical portion at the tip of the convex portion 18 is smaller than the angle θ ₂ of the concave portion 17 having a conical dish shape.

Therefore, only the tip of the convex portion 18 is connected to the concave portion 1.
Rack guide 1 that is in contact with 7 and includes this recess 17
4 is supported so as to be swingable in any direction using the center of the recess 17 as a fulcrum.

In the above configuration, when the direction of movement of the rack 11 is reversed, the rack guide 14 can freely change its angle to maintain good contact with the rack 11, and this allows the sliding of the rack guide 14 to be maintained. It is possible to effectively prevent the surface from hitting the rack 11 unevenly.

5 and 6 show a modification of the first embodiment, in which a rack guide 14 and a screw member 15 are shown.
The feature is that the two are in contact with each other on a spherical surface.

That is, the surface of the rack guide 14 facing the screw member 15 is formed into a spherical surface with a radius of _R1 , and the surface of the screw member 15 facing the rack guide 14 is formed with a radius of R1.
It is formed into a spherical surface with R ₂ . Furthermore, R ₂ has a larger value than R ₁ , so the spherical surfaces are in contact with each other at their centers. Recesses 14a and 15a facing each other are provided in this central portion, and the rack guide 14 is inserted into the rack 11 in the space formed by both recesses 14a and 15a.
A spring 16 is interposed to bias it toward the side.

It is clear that even with this configuration, the same effects as those of the above embodiment can be expected.

7 and 8 show a second embodiment of the present invention, in which 21 is a rack and 23 is a housing. A rack guide 24 and a plate member 22 contacting the back side of the rack guide 24 are sequentially inserted into the housing 23 from the open end thereof, and both members 24, 22 are screw members screwed into the open end of the housing 23. 25 to prevent it from coming off. A spring 26 is interposed between the plate member 22 and the screw member 15, and the rack guide 24 is pressed against the rack 21 with a constant pressure by the force of the spring 26.

A constant gap G is provided between the circumferential surface of the rack guide 24 and the inner circumferential surface of the housing 23, as shown in FIGS. 7 and 8. A recess 27 whose inner bottom is shaped like a conical dish is provided in the center of the surface. As shown in FIGS. 7 and 8, a convex portion 28 having a conical tip protrudes from the center of the surface of the plate member 22 facing the rack guide 24 and is in contact with the concave portion 27. As shown in FIGS. The angle θ ₃ of the conical portion at the tip of the convex portion 28 is equal to
The angle θ of the bottom of the conical dish shape is smaller than ₄ .

Therefore, only the tip of the convex portion 28 is connected to the concave portion 2.
7 and includes this recess 27
4 has its periphery swingable up and down at any position in the horizontal direction using the center of the recess 27 as a fulcrum.

In the above configuration, when the speed of the rack 21 changes suddenly, such as when the direction of movement of the rack 21 is reversed, the rack guide 24 can freely change its angle to maintain good contact with the rack 21. This effectively prevents the sliding surface of the rack guide 24 from coming into partial contact with the rack 21.

9a and 9b show a modification of the second embodiment, in which the bottom of the recess 27 of the rack guide 24 is made into a spherical surface with a radius of _R3 , and the tip of the convex part 28 of the dish member 22 is made with a radius of R. It differs from those shown in FIGS. 7 and 8 in that it is a spherical surface of ₄ , and R ₄ is set to a smaller value than R ₃ .

It is obvious that even with this configuration, the same effects as in the second embodiment can be expected.

Next, FIGS. 10a and 10b show a third embodiment of the present invention, in which 34 is a rack guide;
2 is a plate member disposed in contact with the rear side of the rack guide 34. The back side of the rack guide 34 is formed into an arcuate surface that follows the sliding surface of the rack guide 34, as shown in FIG. A portion 34a is provided.

On the other hand, the surface of the plate member 32 facing the rack guide 34 is connected to the rack guide 34 as shown in FIG. 10b.
4 is formed in the shape of a circular arc groove following the circular arc of the back surface, and in the center thereof, as shown in FIG. The convex portion 34a is in contact with the concave portion 32a, and the other portions are kept in a non-contact state, and the radius R ₅ of the convex portion 34a is the same as the concave portion 32a.
Since the radius R ₆ is smaller than the radius R 6 , only the protruding tip of the protruding portion 34a comes into contact with the concave portion 32a.

Therefore, the rack guide 34
The rack is supported so that the angle can be changed in the longitudinal direction of a rack (not shown) and in a direction orthogonal thereto.

In the above configuration, when the speed of the rack (not shown) suddenly changes, the rack guide 32 freely changes its angle in the reciprocating direction of the rack, that is, in the longitudinal direction of the rack and in the direction perpendicular thereto, and makes contact with the rack. This effectively prevents the sliding surface of the rack guide 34 from hitting the rack unevenly.

In addition, in FIG. 10, the convex portion 34a and the concave portion 32a have been explained as having a circular arc surface, but as shown in FIG. A similar effect can be expected even if it is formed in a V-groove shape. At this time, the angle θ ₅ of the protruding portion 34a is changed to the angle θ ₆ of the concave portion 32a.
Needless to say, the value should be smaller.

12a and 12b show a fourth embodiment of the present invention, in which 44 is a rack guide that slides into contact with a rack (not shown), and 42 is a plate member that comes into contact with the back side of the rack guide 44. The rack guide 44 is swingable relative to the tray member 42 in the sliding direction of a rack (not shown).

That is, a recess 47 whose bottom is V-shaped in a direction perpendicular to the sliding direction of the rack is provided at the center of the rear side of the rack guide 44, and a recess 47 is provided at the center of the rear side of the rack guide 44.
2 is provided with a convex portion 48 having a chevron-shaped tip corresponding to the concave portion 47. Then, the convex portion 48
The angle θ ₇ of the tip is selected to be smaller than the angle θ ₈ of the bottom of the recess 47 and therefore the plate member 42
In this case, only the top of the convex portion 48 is connected to the easy guide 44.
It comes into contact with

In the above configuration, if the speed of the rack (not shown) suddenly changes, the rack guide 44
swings in the sliding direction of the rack and changes its angle to respond to the rack and make good contact with it. At this time, unlike the previous embodiments, the rack guide 44 swings only in the sliding direction of the rack, but since the uneven contact of the sliding surface of the rack guide 44 is most significant at both ends of the rack in the sliding direction, By swinging in the sliding direction, the desired effect can be achieved, and the uneven contact of the sliding surface of the rack guide 44 with the rack can be significantly reduced.

13a and 13b show a modification of the fourth embodiment, in which the inner bottom of the recess 47 of the rack guide 44 is made into an arcuate groove surface with a radius R ₇ , and the dish member 4
The tip of the second convex portion 48 is an arcuate protruding surface having a radius of _R8 , and _R8 is set to a smaller value than _R7 .

It goes without saying that even with this configuration, the same effects as in the fourth embodiment can be expected.

14a and 14b show a fifth embodiment of the present invention. In the figures, 54 is a rack guide, 52 is a dish member disposed in contact with the rear side of the rack guide 54, and the central part of the rear side of the rack guide 54 is is provided with a protruding strip 54a that is perpendicular to the sliding direction of the rack (not shown), and a recessed strip 52a corresponding to the protruding strip 54a is provided on the surface of the dish member 52 facing the rack guide 54. ing. The concave portion 52a is in contact with the convex portion 54a, and the other portions are not in contact with the concave portion 52a.
Since the radius R ₉ of a is smaller than the radius R ₁₀ of the concave portion 52a, only the protruding tip portion of the convex portion 54a comes into contact with the concave portion 52a.

Therefore, the rack guide 54 is held swingably in the reciprocating direction of the rack (not shown), thereby effectively preventing the sliding surface of the rack guide 54 from coming into partial contact with the rack.

In addition, in FIG. 14, the convex strip 54a and the grooved strip 52a have been explained as having a circular arc surface, but as shown in FIG. A similar effect can be expected even if it is formed in a V-groove shape. At this time, it goes without saying that the angle θ ₉ of the protruding portion is set to a smaller value than the angle θ ₁₀ of the concave portion 52a.

As described above, in the present invention, a rack guide that slides into contact with the rack is fitted into the opening of the housing on the back side of the meshing part of the rack with the pinion, and the rack guide presses the rack toward the pinion. In the rack guide device, the rack guide and a supporting member supporting the rack guide are brought into contact with each other by a convex portion formed on one of them and a concave portion formed on the other, and these convex portions and concave portions are connected to the rack guide. The rack guide is swingably supported on the support member by making contact only at the apex in a direction orthogonal to the axial direction of the rack guide, and using the apex as a fulcrum, with a swing gap interposed between the protrusion and the recess; In addition, since a gap is formed between the rack guide and the opening in which it is fitted to allow the rocking of the rack guide, the rack guide can at least move back and forth through the engagement of the concave and convex portions with the support member. It is supported so that it can swing freely in the direction of movement, and there is no contact swinging part between it and the support member, so the swinging can be adapted smoothly without frictional resistance, so the interlocking speed of the rack changes rapidly. In response to this, the contact state of the sliding surface follows suit and becomes stable, making it possible to effectively prevent uneven contact.As a result, the resistance of the sliding surface becomes extremely small, and the sliding surface becomes stable. This has the effect of significantly reducing surface wear.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the conventional example, Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is a sectional view showing the first embodiment of the present invention, and Fig. 4 is a sectional view taken along the - line in Fig. 3. 5 is a sectional view showing a modification thereof, FIG. 6 is a sectional view taken along the - line in FIG. 5, and FIG. 7 is a second cross-sectional view of the present invention.
8 is a sectional view showing the embodiment, FIG. 8 is a sectional view taken along the - line in FIG. 7, FIG. 9 a is a sectional view showing a modification thereof, FIG. 9 b is a sectional view taken along the line - is a cross-sectional view showing the third embodiment of the present invention, and FIG.
11 is a sectional view showing a modification thereof, FIG. 12a is a sectional view showing a fourth embodiment of the present invention, FIG. 13
Figure a is a sectional view showing a modified example, and figure b is a cross-sectional view of the same figure a.
FIG. 14a is a sectional view showing the fifth embodiment of the present invention, and FIG. 14b is a sectional view taken along the line -
A line sectional view, and FIG. 15 is a sectional view showing a modification thereof. 11, 21: Rack, 14, 24, 34, 4
4, 54, 64: Rack guide, 15, 25: Screw member, 16, 26: Spring, 22, 32,
42, 52: plate member.

Claims (1)

[Scope of utility model registration request] In a rack guide device, a rack guide that slides into contact with the rack is fitted into the opening of the housing on the back side of the meshing part of the rack with the pinion, and the rack guide presses the rack toward the pinion side. A supporting member is brought into contact with a convex portion formed on one of the racks and a concave portion formed on the other, and the convex portion and the concave portion are brought into contact with each other at the top of the rack in a direction orthogonal to the axial direction of the rack. The rack guide is swingably supported on the support member with the top part as a fulcrum and a swing gap interposed between the protrusion and the recess, and the rack guide and the opening into which it is fitted are A rack guide device characterized in that a gap is formed between the rack guide and the rack guide to allow swinging of the rack guide.