JP2007303657A - Cross roller bearing - Google Patents

Abstract

A cross roller bearing capable of performing a chamfering operation of a joint portion of a raceway surface formed on both sides of a plug-side raceway surface formed on a plug sealing a roller insertion hole formed in an inner ring by machining. To suggest.
In a cross roller bearing 1, widths W1, W2 of chamfered portions 65, 66, 75, 76 formed at a raceway surface thereof and a protruding corner portion of a joint portion of a plug-side raceway surface 72, respectively. The depth is set based on the diameter D of the cylindrical roller 5. In addition, the chamfered portions are defined by arcuate surfaces S1 and S2 smoothly connected to the raceway surfaces 32 and 72 so that the chamfered portions having these widths and depths are formed. By quantifying the shape of the chamfering process, it is possible to mechanize the chamfering process that relied on the experience and feeling of the worker, thereby making it possible to improve the efficiency of the chamfering operation and suppress variations in performance.
[Selection] Figure 4

Description

  The present invention provides a plug-side track in which a roller insertion hole formed in an annular end surface of a race ring (inner ring or outer ring) is sealed by a plug, and a portion of a raceway surface that is lacking by forming a roller insertion hole is formed in the plug. The present invention relates to a cross roller bearing defined by a surface. More specifically, the present invention relates to a cross roller bearing having a configuration capable of preventing a cylindrical roller from hitting a joint portion between a raceway surface and a plug-side raceway surface and falling into a rotation lock state.

  As is well known, a cross roller bearing is formed by rolling a plurality of cylindrical rollers onto an annular raceway having a rectangular cross section defined between an inner ring and an outer ring in a state of being alternately orthogonal to the circumferential direction. It is configured to be movably inserted. In a cross roller bearing in which an inner ring and an outer ring are integrated, in order to insert a cylindrical roller into an annular raceway, a roller insertion hole is formed in an annular end surface of the raceway ring, for example, an inner ring, and after the cylindrical roller is inserted, the roller The insertion hole is sealed with a plug.

In the cross roller bearing of this structure, one raceway surface defining an annular raceway is divided by a roller insertion hole and is missing. A raceway surface portion for compensating for the lacking portion is formed on the end surface of the plug, and a continuous annular raceway surface is formed in a state where the plug is attached to the roller insertion hole and sealed. Patent Documents 1 and 2 disclose a cross roller bearing having this structure.
JP 2001-56024 A JP 2001-65559 A

  Here, the corners of the inner race side raceway surface and the plug side raceway surface are exposed. For this reason, it is necessary to perform an R-shaped chamfering process on the corner portion so that a smooth rolling motion is not hindered by a cylindrical roller hitting the corner portion.

  However, such chamfering is performed manually, and the current situation is that it relies on the feeling and experience of a skilled worker. For this reason, it has been difficult to manufacture a cross roller bearing that is efficiently and appropriately chamfered.

  In view of this point, an object of the present invention is to propose a cross roller bearing in which a chamfering operation of a joint portion between a raceway surface on a raceway side and a plug-side raceway surface can be performed by machining. .

  In order to solve the above-mentioned problems, the present invention has a roller insertion hole for inserting a cylindrical roller formed in an annular end surface of the bearing ring, and a plug sealing the roller insertion hole. In the cross roller bearing in which the portion lacking by forming the roller insertion hole in the annular raceway surface formed on the plug-side raceway surface defined in the plug is the raceway on the raceway side. Edges on both sides of the surface adjacent to the plug-side raceway surface are chamfered portions defined by convex curved surfaces that are smoothly continuous with the raceway surface, and these chamfered portions are the raceway. The chamfering width W1 in the direction along the surface is a dimension within a range of 0.065 to 0.1 times the diameter of the cylindrical roller, and the chamfering depth in the direction orthogonal to the raceway surface is W1 / 2. As a feature .

  If the chamfered state of the chamfered portion is defined in this way, a smooth rolling motion is always maintained without the cylindrical rollers hitting the edge portions on both sides of the raceway surface on the raceway side. Therefore, it is possible to efficiently perform the chamfering operation of the portion, which has been performed manually by relying on experience, by machining.

  Here, if the convex curved surface defining the chamfered portion is an arc surface inscribed in the raceway surface, it is desirable because processing and management are easy.

  In the present invention, the edge portions on both sides adjacent to the raceway surface on the raceway side of the plug-side raceway surface are also defined by the convex curved surface that is smoothly continuous with the plug-side raceway surface. These plug side surface chamfered portions have a chamfering width W2 in the direction along the plug side raceway surface within a range of 0.065 to 0.1 times the diameter of the cylindrical roller. The chamfering depth in the direction perpendicular to the plug-side raceway surface is W2 / 2.

  Even in this case, it is desirable that the convex curved surface defining the plug side surface chamfered portion is an arc surface inscribed in the plug side raceway surface.

  In this way, the edge portions on both sides of the plug-side raceway surface as well as the edge portions on both sides of the raceway surface on the side of the raceway are chamfered, so that the cylindrical roller can be smoothly smoothed at the joint portion of the raceway surface. It is possible to reliably prevent the rolling motion from being inhibited.

  Next, in the present invention, it is preferable that the plug-side raceway surface is retracted in a radial direction of the raceway surface with respect to the raceway surface on the raceway side.

  In the cross roller bearing of the present invention, the width and depth of the chamfered portion formed at the protruding corner portion of the joint portion between the raceway surface and the plug-side raceway surface are set based on the diameter of the cylindrical roller. In addition, the chamfered portion is defined by a convex curved surface that is smoothly continuous with the raceway surface so that the chamfered portion having such a width and depth is formed. According to the present invention, since the chamfering shape is quantified, it is possible to mechanize the chamfering processing that has conventionally relied on the experience and feeling of the worker, thereby improving the efficiency of chamfering work and performance. Variations can be suppressed.

  A cross roller bearing to which the present invention is applied will be described below with reference to the drawings.

  FIG. 1A is an end view showing an example of a cross roller bearing to which the present invention is applied, and FIG. 1B is a sectional view thereof. As shown in these drawings, the cross roller bearing 1 includes an integral outer ring 2 and an integral inner ring 3. A V-shaped raceway groove 2 a is formed on the inner peripheral surface of the outer ring 2. A V-shaped raceway groove 3a is also formed on the outer peripheral surface of the inner ring 3, and an annular raceway 4 having a rectangular cross section is defined by the pair of raceway grooves 2a and 3a. A plurality of cylindrical rollers 5 are inserted into the annular track 4 so as to roll in the circumferential direction. The cylindrical rollers 5 are arranged in a state in which their central axes are alternately orthogonal.

  A roller insertion hole 6 is formed in the inner ring 3, and the roller insertion hole 6 is sealed with a plug 7. The roller insertion hole 6 is formed by cutting out a part of the annular end surface 31 of the inner ring 3 and is defined by a rectangular groove extending in the radial direction with a certain width from the inner ring outer peripheral surface to the inner peripheral surface. Has been. A plug 7 that is slightly wider or slightly narrower than the width of the hole is press-fitted into the roller insertion hole 6. The plug 7 is press-fitted or inserted, and is fastened and fixed to the inner ring 3 side by fastening bolts 8.

  FIG. 2A is an enlarged partial end view showing the roller insertion hole 6 and FIG. 2B is a partial cross-sectional view thereof. FIG. 3 is an explanatory view showing a portion of the roller insertion hole 6. Referring to these drawings, the plug 7 includes an end surface 71 forming a part of the annular end surface 31 of the inner ring 3 and a part of one raceway surface 32 in the V-shaped inner ring raceway groove 3a. And a plug-side raceway surface 72 that is formed. The end surfaces 73 and 74 on both sides of the plug 7 are in a state of being pressed into the end surfaces 63 and 64 (end surfaces on both sides of the inner ring 3) inside the roller insertion hole 6 or inserted with a slight gap, respectively.

  Here, the edge portions on both sides of the raceway surface 32 of the inner ring 3, that is, the corner portions of the raceway surface 32 and the end surface 63, and the corner portion of the raceway surface 32 and the end surface 64 are chamfered. Yes. In this example, the chamfered portions 65 and 66 are defined by convex curved surfaces. Similarly, chamfering is also applied to the protruding corner portions of the plug-side raceway surface 72 and the end surface 73 and the protruding corner portions of the plug-side raceway surface 72 and the end surface 74 in the plug 7. In this example, the chamfered portions 75 and 76 are defined by convex curved surfaces.

  FIG. 4A is an explanatory diagram showing the chamfered portions 65, 66, 75, and 76 when viewed from the direction indicated by the arrow A in FIG. FIG. 4B is an explanatory view showing the chamfered portions 75 and 76 of the plug 7. FIG. 4C is an explanatory diagram for explaining a curved surface defining the chamfered portions 65 and 75. The shapes of the chamfered portions 65, 66, 75, and 76 will be described with reference to these drawings.

  First, in the chamfered portion 65 of the inner ring 3, the chamfered width W <b> 1 in the direction along the raceway surface 32 is set to a size within a range of 0.065 to 0.1 times the diameter D of the cylindrical roller 5. Further, the chamfering depth in the direction orthogonal to the raceway surface 32, that is, the direction along the end surface 63 is set to W1 / 2. In order to satisfy these width and depth dimensions, a cylinder B1 having a predetermined diameter inscribed in the raceway surface 32 is employed. That is, the inner contact C1 is positioned away from the end face 63 by W1. A point E1 where the cylinder B1 intersects the flat end surface 63 is taken, and an arc surface S1 of the cylinder B1 in the range from the point C1 to the point E1 is adopted as the convex curved surface of the chamfered surface 65. At the point C1, the raceway surface 32 and the arc surface S1 need to be smoothly continued, but at the other point E1, the arc surface S1 does not need to be smoothly continued to the end surface 63. The other chamfered portion 65 has a similar cross-sectional shape.

  In this example, the convex curved surface S2 that defines the chamfered portions 75 and 76 on both sides of the plug 7 is also defined in the same manner. That is, in the chamfered portion 75 on the plug side, the chamfering width W2 in the direction along the plug-side raceway surface 72 is a dimension within a range of 0.065 to 0.1 times the diameter of the cylindrical roller, and is orthogonal to the raceway surface 72. The chamfering depth in the direction (direction along the end face 73) is W2 / 2. A cylinder B2 having a predetermined diameter that is inscribed in the raceway surface 72 is employed so that the inner contact C2 is positioned away from the end surface 73 by W2. A point E2 where the cylinder B2 intersects the flat end surface 63 is taken, and an arcuate surface S2 of the cylinder B2 in the range from the point C2 to the point E2 is adopted as the convex curved surface of the chamfered surface 75. At the point C2, the raceway surface 72 and the arc surface S2 need to be smoothly continued, but at the other point E2, the arc surface S2 need not be smoothly continued to the end surface 73. The other chamfered portion 75 has the same cross-sectional shape.

  In general, the same arc surface may be adopted as the arc surface S1 of the chamfered portions 65 and 66 and the arc surface S2 of the chamfered portions 75 and 76. Of course, a convex curved surface other than the circular arc surface may be adopted. In this example, the plug 7 is fixed to the inner ring 3 with its plug-side raceway surface 72 retracted by a slight dimension Δ with respect to the raceway surface 32.

  As described above, in the cross roller bearing 1 of the present example, the widths of the chamfered portions 65, 66, 75, 76 formed at the protruding corners of the joint portion between the raceway surface 32 and the plug-side raceway surface 72, respectively. The depth is set based on the diameter of the cylindrical roller 5. In addition, the chamfered portion is defined by a convex curved surface that is smoothly continuous with the raceway surface 32 so that the chamfered portion having these widths and depths is formed. By quantifying the chamfering shape in this way, it is possible to mechanize the chamfering processing that has previously relied on the experience and feeling of the worker, thereby improving the efficiency of the chamfering operation and suppressing variations in performance. .

  The above example is a case where the roller insertion hole 6 is formed in the inner ring 3 among the race rings (inner ring, outer ring) of the cross roller bearing, but the present invention is a case where the roller insertion hole is formed in the outer ring 2. The same applies to.

It is the end view and sectional drawing which show an example of the cross roller bearing to which this invention is applied. FIG. 2 is a partial end view and a partial cross-sectional view showing a roller insertion groove formed in the inner ring of FIG. 1 and a stopper attached thereto. It is explanatory drawing which shows the part of the roller insertion hole. (A) is explanatory drawing when it sees from the direction shown by the arrow A in FIG. 2, in order to show a chamfering part, (b) is explanatory drawing which shows the chamfering part of a plug, (c) is a chamfering part. It is explanatory drawing for demonstrating the curved surface which prescribes | regulates.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cross roller bearing 2 Outer ring 3 Inner ring 4 Track 5 Cylindrical roller 6 Roller insertion hole 7 Plug 32 Track surface 63, 64 End surface 65, 66 Chamfer 72 Plug side track surface 73, 74 End surface 75, 76 Chamfer W1, W2 Chamfer Width S1, S2 Convex curved surface defining chamfer

Claims (5)

A roller insertion hole for cylindrical roller insertion formed on the annular end surface of the race ring,
With a plug sealing the roller insertion hole,
In the cross roller bearing in which the portion lacking by forming the roller insertion hole in the annular raceway surface formed in the raceway is defined by the plug side raceway surface formed in the plug,
Edge portions on both sides adjacent to the plug-side raceway surface in the raceway surface on the raceway side are chamfered portions defined by convex curved surfaces that are smoothly continuous with the raceway surface,
These chamfered portions have a chamfering width W1 in a direction along the raceway surface within a range of 0.065 to 0.1 times the diameter of the cylindrical roller, and a chamfer depth in a direction perpendicular to the raceway surface. Is a cross roller bearing characterized by W1 / 2. In claim 1,
The cross roller bearing, wherein the convex curved surface defining the chamfered portion is an arc surface inscribed in the raceway surface. In claim 1,
The plug side raceway surface has both side edge portions adjacent to the raceway surface on the side of the raceway ring, and a plug side chamfer defined by a convex curved surface that is smoothly continuous with the plug side raceway surface. And
These plug side surface chamfered portions have a chamfering width W2 in a direction along the plug side raceway surface within a range of 0.065 to 0.1 times the diameter of the cylindrical roller, and are orthogonal to the plug side raceway surface. A cross roller bearing having a chamfering depth of W2 / 2 in the direction in which it is pushed. In claim 3,
The cross roller bearing, wherein the convex curved surface defining the plug side surface chamfering portion is an arc surface inscribed in the plug side raceway surface. In any one of claims 1 to 4,
The cross roller bearing, wherein the plug-side raceway surface is retreated in the radial direction of the raceway surface with respect to the raceway surface on the raceway side.

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