JP2005163971A - Spider universal joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spider universal joint capable of reducing its manufacturing cost by reducing a rotating diameter while keeping sufficient strength. <P>SOLUTION: A size of the base of a shaft part 5 of a spider 3 is remarkably reduced, whereby a needle bearing 7 can be moved to a center side of the universal joint in its layout, and a maximum rotating diameter (D: maximum rotating diameter of end edge of cup-shaped outer ring 9) of the needle bearing 7 can be remarkably reduced. A maximum rotating diameter of the spider universal joint can be reduced for the sake of the reduction of the maximum rotating diameter D of the needle bearing 7, and a maximum rotating diameter D1 of an arm part 1b of a yoke 1 can be determined to be the maximum rotating diameter D of the needle bearing 7 or less when a joint angle is 0 degree. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a universal joint for use in, for example, a vehicle steering apparatus.

  For example, as disclosed in Patent Documents 1 and 2, the cruciform universal joint is interposed in a steering shaft of a vehicle, and a cruciform spider is interposed between a pair of yokes via a needle bearing. It is attached. That is, the shaft portion of the spider is fitted into the bearing hole of the yoke via the needle bearing.

  In patent document 1, the axial direction groove | channel is formed in the bearing hole inner peripheral surface of a yoke, and this makes it easy to incorporate the spider shaft portion into the spider bearing hole.

Moreover, in patent document 2, the partial chamfering is provided in the front-end | tip surface of the axial part of a spider, and this makes it easy to incorporate the spider axial part into the yoke bearing hole.
Japanese Patent Laid-Open No. 2002-5187 Japanese Patent Laid-Open No. 11-37171

  Such a cross joint with a universal joint for steering is generally required to have a small space around the use site (margin space) and a small rotation diameter.

  In particular, in the case of a tilt type steering column, when the tilt pivot (swing center) is disposed relatively close to the steering wheel (reference publication: Japanese Patent Laid-Open No. 11-208483, etc.), this tilt pivot (swinging) The cross joint universal joint used for the center) is highly required to make the tilt type steering column compact.

  However, the diameter of the spider shaft cannot be reduced due to the strength of the cross shaft universal joint, and the fitting length with the needle bearing cannot be shortened.

  Also, the yoke cannot be reduced in the outer width and the inner width dimension of the arm portion because of the strength and the necessity of incorporating the spider.

  For this reason, it is relatively difficult to manufacture a cross joint with a small rotation diameter.

  Patent Documents 1 and 2 are proposals for solving these problems. However, additional processing is required for the parts, which may lead to an increase in manufacturing cost, and the effect is small, which may be insufficient to make the tilt type steering column compact.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a cross joint having a sufficient strength, a small rotation diameter, and a reduced manufacturing cost.

In order to achieve the above object, a cross shaft universal joint according to claim 1 of the present invention has a cross shaft spider mounted between a pair of yokes, and the spider has a bearing hole in the yoke. In the cross joint with the shaft fitted through the bearing,
The maximum rotation diameter of the yoke is set to be equal to or less than the maximum rotation diameter of the bearing when the joint angle is 0 degree.

  The cross shaft universal joint according to claim 2 of the present invention is characterized in that a diameter of a shaft portion of the spider is φ9 mm to φ10.4 mm.

  In the cross joint according to a third aspect of the present invention, the diameter of the bearing hole of the yoke is φ14.8 mm to φ16.4 mm.

  The cross joint according to claim 4 of the present invention is characterized in that a fitting allowance of the bearing hole of the yoke with respect to the shaft portion of the spider is 3.5 mm or more.

  As described above, according to the present invention, the position of the bearing is moved to the center side of the universal joint as a layout, so that the maximum rotation diameter of the bearing is reduced and the bearing hole of the yoke with respect to the shaft portion of the spider is reduced. Since the fitting allowance is 3.5 mm or more, the maximum rotation diameter of the cross joint can be reduced while having sufficient strength.

  As a result, the spider shaft portion can be easily incorporated into the yoke bearing hole, and the manufacturing cost is not increased, and the tilt type steering column can be made compact.

  Hereinafter, a cross joint according to an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
Fig.1 (a) is a side view of the cross-joint universal joint which concerns on 1st Embodiment of this invention, (b) is sectional drawing along the bb line of (a), (c ) Is an arrow view of arrow c in (a).

  2A is a side view of the spider and the spider piece shown in FIG. 1, FIG. 2B is a cross-sectional view taken along line bb in FIG. 1A, and FIG. It is an arrow line view of the arrow c of a).

  3A is a side view of the cross shaft universal joint shown in FIG. 1 with a joint angle, and FIG. 3B shows a spider and a spider piece on the yoke shown in FIG. FIG.

  The cross joint according to the present embodiment is a tilt type steering column that can adjust the tilt angle of the steering wheel of the vehicle, and the tilt pivot (swing center) is disposed relatively close to the steering wheel ( Reference gazette: suitable for JP-A-11-208483.

  In the present embodiment, as shown in FIG. 1, the pair of yokes 1 and 2 includes a pair of arm portions 1b and 2b connected to the pair of shafts 1a and 2a by welding or the like, and these arm portions 1b and 2b, respectively. And a pair of bearing holes 1c and 2c formed at the front end portion.

  As shown in FIG.1 (c), the outer peripheral surface of each arm part 1b is formed in circular arc shape, The rotation diameter is set to (D1). Note that this shape is not limited to an arc, and may be any shape as long as it does not protrude from the circle (D1).

  The spader 3 includes a body portion 4 and four shaft portions 5, 5, 5, 5 formed in a cross shape on the body portion 4, and a spider piece 6 is provided at the tip of each shaft portion 5. It is buried. In addition, the outer peripheral surface of the trunk | drum 4 is formed in spherical shape as shown in FIG.2 (b), and the diameter is (N).

  Each shaft portion 5 is fitted in a bearing hole 1 c of each yoke 1 via a needle bearing 7. The needle bearing 7 includes a needle 8 that rolls on the outer peripheral raceway surface of the shaft portion 5, and a shell or cup-shaped outer ring 9 that supports the outer peripheral side of the needle 8.

  As shown in FIG. 1B, in the needle bearing 7, the end edge of the cup-shaped outer ring 9 has a maximum diameter (D) as a bearing during rotation.

  The needle 8 may be interference fit. Further, the axial clearance of the needle 8 may be 0.6 mm or more. Further, crowning may be performed so that the diameters of both ends of the needle 8 are gradually reduced.

  In the present embodiment, the dimension (S) of the gap between the root of the shaft part 5 and the outer ring 9 is used as shown in FIG. Is formed significantly smaller than before. In addition, there exist patent document 2 and Unexamined-Japanese-Patent No. 9-133151 as a reference gazette of the conventional seal ring.

  Thus, since the dimension (S) of the clearance between the root of the shaft portion 5 and the outer ring 9 is formed to be significantly smaller than before, the needle bearing 7 can be moved to the center side of the universal joint as a layout. Thus, the maximum rotation diameter of the needle bearing 7 (D: the maximum rotation diameter of the end edge of the cup-shaped outer ring 9) can be made smaller than before.

  Along with this, the maximum rotation diameter (D) of the needle bearing 7 is reduced, so that the maximum rotation diameter of the cross joint is reduced, and when the joint angle is 0 degree, FIG. As shown in FIG. 4, the maximum rotation diameter (D1) of the arm portion 1b of the yoke 1 can be set to be equal to or less than the maximum rotation diameter (D) of the needle bearing 7.

  That is, when the joint angle is 0 degree, that is, when the intersection angle between the shaft 1a and the shaft 2a is 0 degree, (D) ≧ (D1) can be satisfied (however, as will be described later, the joint angle is Excluded when connected).

  In addition, since the spider 3 does not use a seal ring, it is not necessary to consider the seal receiving surface 10 that has been necessary in the past, and when the spider 3 is incorporated into the bearing hole 1c of the yoke 1, it does not interfere with the spider 3 in the past. The required outer diameter (M) of the seal receiving surface 10 can be made sufficiently small.

  As a dimension related to the outer diameter (M), the diameter (N) of the spherical surface of the body portion 4 can also be reduced.

  The spider 3 is incorporated into the fitting hole 1c of the yoke 1 by moving the spider 3 in the direction of the arrow shown in FIG.

  At this time, when the shaft portion 5 of the spider 3 is incorporated into the bearing hole 1c of the yoke 1, the maximum rotation diameter (D) of the needle bearing 7 is reduced and the above diameters (M) and (N) are sufficiently increased. Since it is small, it can be performed easily.

  Moreover, in this Embodiment, although the spider 3 has manufactured the raw material by cold forging, it may be hot forging.

  Moreover, as shown in FIG.2 (b), the diameter (d) of the axial part 5 is formed in (phi) 9mm-(phi) 10.4mm from the surface of the intensity | strength at the time of use and a rotation diameter. This is because as the diameter of the shaft portion 5 increases, the rotational diameter also increases. Preferably, it is about φ10 mm which is the same as that generally used for many passenger cars at present. As a result, the conventional needle bearing can be used as it is, and an increase in cost can be prevented.

  Further, the “fitting allowance” (K) between the bearing hole 1c of the yoke 1 and the shaft portion 5 of the spider 3 is set to 3.5 mm or more in order to ensure strength.

  From the above, according to the present embodiment, the position of the needle bearing 7 is moved to the center side of the universal joint as a layout, so that the maximum rotational diameter (D) of the needle bearing 7 is reduced and the axis of the spider 3 is Since the fitting allowance of the bearing hole 1c of the yoke 1 with respect to the portion 5 is 3.5 mm or more, the maximum rotation diameter of the cross shaft universal joint can be reduced while having sufficient strength.

  This facilitates the incorporation of the shaft portion 5 of the spider 3 into the bearing hole 1c of the yoke 1 and contributes to the compactness of the tilt type steering column without increasing the manufacturing cost. can do.

  Further, the outer diameter (D1) of the arm portion 1b of the yoke 1 has a relationship of (D) ≧ (D1) with respect to the rotational diameter (D) of the needle bearing 7 as described above.

  Therefore, the rotation diameter of the cross joint is reduced as much as the rotation diameter (D) of the needle bearing 7 is reduced.

  However, when the joint angle is added, the maximum rotation diameter may be the tip 1d of the arm 1b of the yoke 1 as shown in FIG. In this case, the outer diameter (R × 2) of the tip 1d of the arm 1b of the yoke 1 is the maximum rotation diameter.

  Where the maximum rotation diameter is determined depends on the joint angle used, and the dimensions (D), (D1), and (E). Here, (E) is the distance between the center of the spider piece 6 and the tip 1d of the arm 1b.

  In the case of the present embodiment, when the maximum rotation diameter becomes the tip 1d of the arm 1b, in order to make the rotation diameter as small as possible, the maximum dimension (E) is set to the radius of the bearing hole 1c of the yoke 1. (+2.6 mm).

  Although not shown, a chamfer may be provided at the tip 1d of the arm 1b in order to reduce the rotation diameter (reference publication: Japanese Utility Model Publication No. 5-3652).

  Further, when used for tilting, the joint angle used is about 20 degrees at maximum, although it varies depending on the vehicle type.

  As shown in FIG. 1 (a), the outer diameters of the yokes 1 and 2 are arcs centered on the shafts 1a and 2a. However, (D) ≧ (D1) is satisfied and caulking (11) is satisfied. As long as there is a step (T) that can be performed, any shape may be used. The step (T) usually needs to be 0.5 mm or more.

  The outer diameter of the needle bearing 7 is φ14.8 mm to φ16.4 mm, preferably a nominal diameter φ15 mm or φ16 mm.

  The materials of the yokes 1 and 2 are made of cold forging, and reference numerals 1e and 2e indicate escape when the spider is assembled.

  The joint between the yokes 1 and 2 and the shafts 1a and 2a is the circumferential welded portions 1e and 2e, but it may be constituted by a combination of serration fitting and caulking (Reference: JP-A-11-208483). Issue gazette).

  Alternatively, the yokes 1 and 2 and the shafts 1a and 2a may be coupled by bolt tightening (Reference: Patent Document 2). In this case, the bolt portion has the maximum rotation diameter, and the rotation diameter does not decrease when the entire universal joint is considered. However, since the central part of the universal joint becomes small, the peripheral part can be downsized.

  The maximum rotation diameter (D) of the present embodiment could be 38 mm in nominal diameter. The maximum rotation diameter in the past (reference publication: Japanese Patent Laid-Open No. 11-208483, etc.) is 42 mm in nominal diameter, and can be reduced by 4 mm compared to the conventional one (state in which the joint angle is 0 degree).

(Second Embodiment)
Fig.4 (a) is a side view of the cross-joint universal joint which concerns on 2nd Embodiment of this invention, (b) is sectional drawing along the bb line of (a).

  As is apparent from the drawings, this embodiment has the same basic structure as the first embodiment described above, and only differences will be described.

  In the present embodiment, the yokes 1 and 2 are formed by pressing.

  Further, notches 1f and 2f are formed in the arm portions 1b and 2b of the yokes 1 and 2, respectively. Thereby, a predetermined joint angle (20 degrees in this embodiment) is obtained.

(Third embodiment)
FIG. 5A is a side view of a cruciform universal joint according to a third embodiment of the present invention, and FIG. 5B is a cross-sectional view taken along line bb in FIG. ) Is an arrow view of arrow c in (a).

  As is apparent from the drawings, this embodiment has the same basic structure as the first embodiment described above, and only differences will be described.

  In the present embodiment, the yokes 1 and 2 are formed by cold forging.

  Further, no spider piece is used, and the bottom surface 9 a of the cup-shaped outer ring 9 of the needle bearing 7 is in direct contact with the tip surface of the shaft portion 5 of the spider 3.

  Further, notches 1g and 2g are formed in the arm portions 1b and 2b of the yokes 1 and 2, respectively. Thereby, a predetermined joint angle is obtained. The maximum rotation diameter of the present embodiment could be set to φ36 as a nominal diameter.

(Fourth embodiment)
FIG. 6 is a cross-sectional view of a cross shaft universal joint according to a third embodiment of the present invention.

  As is clear from the drawings, this embodiment has the same basic structure as the third (or first) embodiment described above, and only differences will be described.

  In the present embodiment, the yokes 1 and 2 are formed by hot forging.

  In addition, this invention is not limited to embodiment mentioned above, A various deformation | transformation is possible.

(A) is a side view of the cross-joint universal joint which concerns on 1st Embodiment of this invention, (b) is sectional drawing along the bb line of (a), (c) is It is an arrow line view of the arrow c of (a). (A) is a side view of the spider and spider piece shown in FIG. 1, (b) is a sectional view taken along line bb in (a), and (c) is (a). FIG. (A) is the cross-axis universal joint shown in FIG. 1, and is a side view with the joint angle attached, and (b) is the yoke shown in FIG. 1 with a spider and a spider piece. It is a figure which shows the state to assemble | attach. (A) is a side view of the cross-joint universal joint which concerns on 2nd Embodiment of this invention, (b) is sectional drawing along the bb line of (a). (A) is a side view of the cross-joint universal joint which concerns on 3rd Embodiment of this invention, (b) is sectional drawing along the bb line of (a), (c) is It is an arrow line view of the arrow c of (a). It is sectional drawing of the cross-axis universal joint which concerns on 3rd Embodiment of this invention.

Explanation of symbols

1, 2 Yoke 1a, 2a Shaft 1b, 2b Arm 1c, 2c Bearing hole 1d Tip 1e, 2e Circumferential weld 1f, 2f Notch 1g, 2g Notch 3 Spider 4 Body 5 Shaft 6 Spider Piece 7 Needle bearing 8 Needle 9 Cup-shaped outer ring 9a Bottom surface 10 Seal receiving surface 11 Caulking portion

Claims (4)

In a cross shaft universal joint in which a cross shaft spider is mounted between a pair of yokes, and the shaft portion of the spider is fitted to the bearing hole of the yoke via a bearing,
The maximum rotational diameter of the yoke is set to be equal to or less than the maximum rotational diameter of the bearing when the joint angle is 0 degree.   2. The cross shaft universal joint according to claim 1, wherein a diameter of a shaft portion of the spider is φ9 mm to φ10.4 mm.   2. The cross shaft universal joint according to claim 1, wherein a diameter of the bearing hole of the yoke is φ14.8 mm to φ16.4 mm.   The cross shaft universal joint according to claim 1, wherein a fitting margin of the bearing hole of the yoke with respect to the shaft portion of the spider is 3.5 mm or more.

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