JP4280579B2 - Friction imparting structure to rotating shaft - Google Patents

Description

  According to the present invention, the contact portion of the contact member assembled to the housing that rotatably supports the rotating shaft is slidably brought into contact with the outer peripheral surface of the rotating shaft, so that friction is applied to the rotating shaft. The present invention relates to a structure for imparting friction to a rotating shaft configured as described above.

A contact portion of a contact member assembled to a housing (for example, a column housing) that rotatably supports a rotating shaft (for example, a steering shaft) slidably contacts the outer peripheral surface of the rotating shaft. There is an apparatus configured to apply friction (see, for example, Patent Document 1).
JP 2000-205263 A

  In the conventional apparatus described above, the contact portion between the rotating shaft and the contact member may be fixed on the contact surface, and the rotation of the rotating shaft may be hindered. Therefore, an object of the present invention is to prevent the rotation of the rotating shaft from being hindered even when the contact portion between the rotating shaft and the contact member is fixed on the contact surface.

In order to achieve such an object, according to the present invention, a contact portion of a contact member assembled to a housing that rotatably supports a rotating shaft contacts the outer peripheral surface of the rotating shaft so as to be slidable. A structure for applying friction to a rotating shaft configured to apply friction to the shaft, wherein the contact member is directly engaged with a fixture and is fixed to the housing via the fixture. to together, the engagement of the contact member and the fixed member is configured such that the contact member is released by the rotation force of the predetermined value or more is rotatable with respect to the fixture, the said contact member The contact portion is provided by being displaced by a predetermined amount in the axial direction with respect to the fixture, and the contact portion is interposed between the contact portion and the housing by an elastic body contacting the contact portion and the housing. Particular is characterized biased toward the outer periphery of the rolling shaft.

  In this friction applying structure, normally, the contact portion of the contact member assembled to the housing via the fixture is slidably in contact with the outer peripheral surface of the rotating shaft, and friction is applied to the rotating shaft. Further, when the contact portion of the contact member is fixed to the outer peripheral surface of the rotating shaft, when the rotational force transmitted from the rotating shaft to the contact member becomes a predetermined value or more, the engagement between the contact member and the fixture is released, The rotating shaft and the contact member can be rotated with respect to the fixture. Therefore, even when the contact portion between the rotating shaft and the contact member is fixed on the contact surface, the rotation of the rotating shaft is not hindered.

Further, in this friction applying structure, in addition to the above-described actions and effects, the contact portion of the contact member is provided by being displaced by a predetermined amount in the axial direction with respect to the fixed ring, and is provided on the outer periphery of the rotating shaft by the elastic body. Since it is urged | biased toward the surface, the contact part of a contact member contacts the outer peripheral surface of a rotating shaft exactly at normal time, and friction is correctly given to a rotating shaft.

  In carrying out the present invention, the fixture is a metal fixing ring that is press-fitted and fixed to the housing on the outer periphery of the rotary shaft, and has a radial through hole, and the contact member is made of resin. There is a protrusion that is engaged and held by the fixing ring and fits into the through hole, and the engagement between the contact member and the fixing ring is released when the protrusion is broken by a rotational force of a predetermined value or more. Further, the contact member can be configured to be rotatable with respect to the fixing ring.

  In this friction applying structure, the contact portion of the contact member assembled to the housing via the fixing ring press-fitted and fixed to the housing is normally slidably in contact with the outer peripheral surface of the rotating shaft. Is given friction. In addition, when the contact portion of the contact member is fixed to the outer peripheral surface of the rotating shaft, the contact member protrusion breaks (shears) when the rotational force transmitted from the rotating shaft to the contact member exceeds a predetermined value. The engagement between the member and the fixing ring is released, and the rotating shaft and the contact member can rotate with respect to the fixing ring. Therefore, even when the contact portion between the rotating shaft and the contact member is fixed on the contact surface, the rotation of the rotating shaft is not hindered. Moreover, since this friction provision structure is a simple structure, it can be implemented at low cost.

In carrying out the present invention, the elastic body can be also rubber ring der Rukoto elastically deformed by contact with the and interposed between the said contact portion housing said contact housing.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 to 3 show an embodiment in which a structure for applying friction to a rotating shaft according to the present invention is implemented in a steering column device for a vehicle. In this embodiment, a steering shaft 11 as a rotating shaft is a ball bearing. A column housing (sometimes called a column tube) 13 is assembled through 12 and supported rotatably.

  A friction applying assembly 20 is interposed between the steering shaft 11 and the column housing 13. The friction imparting assembly 20 is for imparting friction to the steering shaft 11, and as shown in FIGS. 1 to 3, is constituted by a contact member 21, a fixed ring 22, and an O ring 23. Before the shaft 11 and the ball bearing 12 are assembled to the column housing 13, they are assembled into the column housing 13 by press-fitting from the right (rear) in FIG.

  After the friction applying assembly 20 is assembled to the column housing 13, the steering shaft 11 is inserted into the column housing 13 and the friction applying assembly 20 from the left (front) in FIG. Further, the ball bearing 12 is assembled between the steering shaft 11 and the column housing 13 from the right side (rear side) in FIG. The clip 14 attached to the shaft 11 is prevented from coming off. Further, a steering wheel 15 is integrally assembled to the right end (rear end) of the steering shaft 11 in FIG.

  The contact member 21 is formed in a substantially cylindrical shape by a resin, and has an annular mounting portion 21 a for mounting the fixing ring 22, a ring-shaped groove portion 21 b for mounting the O-ring 23, and the outer peripheral surface of the steering shaft 11. It has the annular contact part 21c which contacts slidably. The contact member 21 is formed with a plurality (three) of slits 21d extending a predetermined amount from the front end to the rear, and a plurality (three) of a predetermined amount extending from the rear end to the front. A slit 21e is formed.

  The annular mounting portion 21a has an inner diameter that is slightly larger than the inner diameter of the annular contact portion 21c, can be bent slightly inwardly, and protrudes a predetermined amount outwardly from the outer periphery thereof. A plurality of (three) protrusions 21a1 that are broken (sheared) by a rotational force of a predetermined value or more are formed. The ring-shaped groove 21b is formed on the outer periphery of the substantially central portion of the annular contact portion 21c. The annular contact portion 21c is provided by being displaced by a predetermined amount in the axial direction with respect to the fixed ring 22, and slidably contacts the outer peripheral surface of the steering shaft 11 on the inner peripheral surface thereof.

  The fixing ring 22 is formed of a metal in a cylindrical shape, and has a plurality (three) of radial through holes 22a into which a plurality (three) of protrusions 21a1 formed in the annular mounting portion 21a are fitted. Before the friction applying assembly 20 is assembled to the column housing 13, a plurality (three) of the annular mounting portion 21a of the contact member 21 is bent slightly inward in the radial direction. The protrusions 21a1 are assembled in advance to the contact member 21 so as to fit into a plurality (three) of the through holes 22a (see FIGS. 2 and 3). Further, when the friction applying assembly 20 is assembled to the column housing 13 (the state shown in FIG. 1), the fixing ring 22 is press-fitted and fixed to the column housing 13.

  In a state in which the fixing ring 22 is press-fitted and fixed to the column housing 13 and integrally assembled, the contact member 21 is engaged and held on the fixing ring 22 by a plurality (three) of protrusions 21a1. 21 is fixed to the column housing 13 via a fixing ring 22. For this reason, in this state, the plurality of (three) protrusions 21 a 1 are broken by a rotational force of a predetermined value or more, so that the engagement between the contact member 21 and the fixing ring 22 is released and the contact member 21 becomes the fixing ring 22. In contrast, it can be rotated.

The O-ring 23 is a rubber ring having a circular cross section, and is assembled in advance in the ring-shaped groove 21 b of the contact member 21 before the friction applying assembly 20 is assembled in the column housing 13. In the state where the friction applying assembly 20 is assembled to the column housing 13 (the state shown in FIG. 1), the O-ring 23 is interposed between the column housing 13 and the annular contact portion 21c of the contact member 21, and the contact portion 21c. And the housing 13 is elastically deformed to urge the annular contact portion 21c of the contact member 21 toward the outer periphery of the steering shaft 11.

  In the friction applying structure of this embodiment configured as described above, the contact portion 21c of the contact member 22 assembled to the column housing 13 via the fixing ring 22 press-fitted and fixed to the column housing 13 is normally provided. The steering shaft 11 is slidably in contact with the outer peripheral surface of the steering shaft 11, and friction is applied to the steering shaft 11. For this reason, it is possible to improve the feeling of response in the steering device, and it is possible to effectively block the transmission of vibration from the road surface to the steering wheel 15.

  In the friction application structure of this embodiment, when the contact portion 21c of the contact member 21 is fixed to the outer peripheral surface of the steering shaft 11, the rotational force transmitted from the steering shaft 11 to the contact member 21 becomes a predetermined value or more. Further, the protrusion 21 a 1 of the contact member 21 is broken (sheared), so that the engagement between the contact member 21 and the fixing ring 22 is released, and the steering shaft 11 and the contact member 21 can rotate with respect to the fixing ring 22. Therefore, even when the steering shaft 11 and the contact portion 21c of the contact member 21 are fixed on the contact surface, the rotation of the steering shaft 11 is not hindered. In addition, the friction applying structure of this embodiment is a simple structure using a simple friction applying assembly 20 configured by assembling the fixing ring 22 and the O-ring 23 to the contact member 21, so that it should be implemented at a low cost. Is possible.

  In the friction applying structure of this embodiment, the contact portion 21c of the contact member 21 is provided with a predetermined amount of displacement in the axial direction with respect to the fixing ring 22, and is interposed between the contact portion 21c and the column housing 13. The contact portion 21 c is urged toward the outer periphery of the steering rotation shaft 11 by the O-ring 23. For this reason, in normal times, the contact portion 21c of the contact member 21 accurately contacts the outer peripheral surface of the steering shaft 11, and friction is accurately imparted to the steering shaft 11.

  In the above embodiment, the friction applying structure according to the present invention is applied to the steering column device for a vehicle. However, the contact portion of the contact member assembled to the housing that rotatably supports the rotating shaft is formed on the outer peripheral surface of the rotating shaft. It is also possible to implement the present invention at other locations configured to come into slidable contact. Moreover, in the said embodiment, although the O-ring 23 was employ | adopted as an elastic body which urges | biases the contact part 21c of the contact member 21 toward the outer periphery of the steering shaft 11, it may implement also employ | adopting another elastic body. Is possible.

It is a vertical side view which shows embodiment which implemented the friction provision structure to the rotating shaft by this invention in the steering column apparatus for vehicles. It is a perspective view of the friction provision assembly shown in FIG. It is a vertical side view of the friction provision assembly shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Steering shaft, 12 ... Ball bearing, 13 ... Column housing, 14 ... Clip, 20 ... Friction grant assembly, 21 ... Contact member, 21a ... Ring attachment part, 21a1 ... Projection, 21b ... Ring-shaped groove part, 21c ... Ring Contact part, 21d, 21e ... slit, 22 ... fixing ring, 23 ... O-ring

Claims (3)

Rotation configured such that friction is imparted to the rotating shaft when the contact portion of the contact member assembled to the housing that rotatably supports the rotating shaft contacts the outer peripheral surface of the rotating shaft slidably. A structure for imparting friction to a shaft, wherein the contact member is directly engaged with a fixture and is fixed to the housing via the fixture, and the engagement between the contact member and the fixture. The contact member is configured to be released by a rotational force of a predetermined value or more so that the contact member can rotate with respect to the fixture, and the contact portion of the contact member is axial with respect to the fixture. be provided with a predetermined amount displaced, the contact portion by the elastic member in contact with the housing and the contact portion interposed between the housing and the contact portion is biased toward the outer periphery of the rotary shaft Friction providing structure to the rotating shaft, wherein the door.   The friction imparting structure to the rotating shaft according to claim 1, wherein the fixture is a metal fixing ring that is press-fitted and fixed to the housing on the outer periphery of the rotating shaft, and has a radial through hole, The contact member is made of resin and has a protrusion that is engaged and held by the fixing ring and fits into the through-hole. The protrusion and the fixing member are fixed when the protrusion is broken by a rotational force of a predetermined value or more. A structure for imparting friction to a rotating shaft, wherein the engagement of the ring is released and the contact member is configured to be rotatable with respect to the fixed ring. A friction imparting structure to the rotation shaft according to claim 1 or 2, a rubber ring der Rukoto the elastic body elastically deformed by contact with the said contact portion interposed between the said contact part housing housing A structure for imparting friction to a rotating shaft.

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