JP7372417B2 - cross roller bearing - Google Patents

Description

This invention comprises, for example, an outer ring, an inner ring that rotates relative to the outer ring, and rollers that are rolling elements disposed between the two, and an assembly hole is formed in either the outer ring or the inner ring for incorporating the roller. Regarding cross roller bearings.

In recent years, crossed roller bearings have been used in various devices such as industrial robots, measurement and inspection equipment, medical equipment, and optical equipment that have rotating parts such as joints, rotating parts, and swinging parts that receive loads in multiple directions. Various types, structures, and sizes have been commercialized depending on the application, and there is a demand for products that are smaller, lighter, more accurate, and have lower manufacturing costs.

BACKGROUND ART Conventionally, a swing bearing is known that is composed of an outer ring and an inner ring that rotates relative to the outer ring via rollers that are rolling elements. The slewing bearing has a notch formed in the end surface of the bearing ring with a notch surface parallel to the circumferential direction, which serves as a roller installation hole, and the installation hole is closed with a lid having a matching shape. Further, in the above-mentioned swing bearing, the lid is fitted into the insertion window and fixed with a pin, and the inner ring is heat-treated and processed at the same time to reduce the level difference (see, for example, Patent Document 1).

Further, as a method for manufacturing a cross roller bearing, a method is known in which a cylindrical roller is inserted into a raceway groove through a roller insertion hole formed on an end face of an inner ring. The cross roller bearing has roller insertion grooves formed in the annular end surface of the inner ring. In the above manufacturing method, after forming a roller insertion groove in the inner ring, a plug is press-fitted into the groove, and in this state, the inner ring is ground to a perfect circle. Next, when the press-fitted stopper is removed, the inner ring becomes slightly constricted. If the rollers are inserted in this state, the gap between the roller insertion portions between the inner ring and the outer ring will be widened, making it easier to insert the cylindrical rollers. After the rollers are inserted, the inner ring returns to a perfect circle state by press-fitting the plug into the roller insertion groove (for example, see Patent Document 2).

Furthermore, a cross roller bearing with a lid is known in which a lid is fitted into a roller mounting hole formed on the outer surface of a bearing ring to realize smooth rotation at high speed. In this cross roller bearing, rollers are disposed through a mounting hole between an outer ring and an inner ring, and a lid is fitted into the mounting hole. The outer surface of the lid is ground at the same time as the outer circumferential surface of the outer ring and fixed in a recessed position from the outer circumferential surface, and the raceway surface on the inner surface of the lid is ground simultaneously with the raceway surface of the inner circumferential surface of the outer ring so that they are flush with each other. (For example, see Patent Document 3).

Further, as a cross roller bearing, one is known in which an insertion hole is formed in the end face of an inner ring or an outer ring, and the side surface of a plug that closes the insertion hole is formed into a tapered part. In the cross roller bearing, a plug having a rectangular shape when viewed in the axial direction and having a rolling surface on which the cylindrical rollers roll, two radial outer surfaces and a circumferential outer surface is fitted and fixed in the insertion hole. The radial outer surface that abuts the radial inner surface of the insertion hole and the circumferential outer surface that abuts the circumferential inner surface of the insertion hole are formed in a tapered shape for positioning in the radial and circumferential directions (for example, as disclosed in the patent (See Reference 4).

Furthermore, there is known a cross roller bearing in which a stopper is positioned with respect to a roller insertion hole formed in an inner ring without hitting a pin. The cross roller bearing has a plug fixed to a roller insertion hole formed in the inner ring. The inner peripheral side surface of the roller insertion hole is formed with left and right flat surface portions and a semicircular concave surface portion that is smoothly continuous with these flat surface portions. The outer circumferential side surface of the stopper is formed with a flat surface portion that is in close contact with the above-mentioned flat surface portion, and a semicircular convex surface portion that is in close contact with the above-mentioned concave surface portion. When the stopper is inserted into the roller insertion hole, these parts come into close contact, and the stopper is automatically positioned in the radial direction and the direction perpendicular thereto. Further, a groove is provided on the bottom surface in the axial direction of the roller insertion hole, and a protrusion that fits into the groove is provided on the lid, and the rollers are positioned by fitting together. Therefore, there is no need to fix the stopper using a positioning pin or the like (see, for example, Patent Document 5).

FR2142793 publication Japanese Patent Application Publication No. 2001-065559 Japanese Patent Application Publication No. 2005-180578 Japanese Patent Application Publication No. 2011-106544 Japanese Patent Application Publication No. 2000-179545

By the way, cross roller bearings are used in rotating parts of robot joints, precision instruments, etc., and high rotation accuracy is required. Further, in the cross roller bearing, an assembly hole for incorporating a roller, that is, a cylindrical roller, is formed in an outer ring or an inner ring, which is a bearing ring, and a lid is provided to close the assembly hole. However, when the cross roller bearing rotates, noise and abnormal sounds may occur. One of the causes of this is when the lid is misaligned, creating a step between the raceway surface of the outer ring or the inner ring and the raceway surface of the lid, and when the rollers roll on the raceway, the step occurs. This is thought to occur when overcoming the Therefore, in cross roller bearings, after attaching the lid to the raceway ring and simultaneously machining the raceway surface of the raceway ring and the raceway surface of the lid, when loading the rolling elements into the installation hole, the lid is attached to the raceway ring. After removing the lid from the hole and loading the rolling element from the installation hole into the raceway, the lid is reattached to the installation hole, but in order to prevent the lid from shifting into the installation hole during installation, There was a problem of how to configure the assembly hole, and there was also a need to eliminate the level difference between the bearing ring and the lid, which causes abnormal noise and rotational problems, in cross roller bearings.

In addition, in the integrated raceway type swing bearings disclosed in Patent Documents 1, 2, 4, and 5, as a method of incorporating rolling elements into the raceway, a part of the raceway is cut out to form an opening in the raceway. is forming. Further, in the covered cross roller bearing of Patent Document 3, a technique is disclosed in which a mounting hole is formed that reaches the raceway from the outer periphery or the inner periphery and rolling elements are respectively installed. Furthermore, in both patent documents, heat treatment or grinding is performed with a lid that closes the roller insertion portion attached, and after the lid is removed and the rolling elements are inserted into the raceway, the lid is reattached to the assembly hole. It is designed to reduce the level difference between the lid and the raceway.

In addition, in the cross roller bearings of Patent Documents 1 to 3, the lid and raceway surface machining method uses only pins or screws to position the lid, and depending on the dimensional difference of the parts and machining ability, the lid may be removed and the rollers inserted. After that, when the lid was reattached with pins or screws, the lid would be positioned at a different position than when the raceway surface was machined, potentially causing misalignment. In addition, in the cross roller bearing of Patent Document 4, the contact surface between the lid and the notch is tapered in the axial direction, and positioning is performed by abutting against the bearing ring in the circumferential direction and radial direction. This is done by machining the part with an abutting surface, or by forming an abutting surface using a separate part from the lid body, and positioning the lid and the notch part with corresponding taper surfaces. It required machining in the axial direction, and there was room for improvement in machinability and reduction in the number of parts. Further, in Patent Document 5, as in Patent Document 4, it was necessary to process a portion in the radial direction while leaving a part, and it was necessary to process the grooves and protrusions of the fitting portion with high precision.

The purpose of this invention is to solve the above-mentioned problem, and the contact part between the lid and the notch part in which the inner ring or the outer ring is formed with the built-in hole is formed with a notch step part and a convex step part. By providing an uneven locking part and fitting the lid to the raceway ring, the unevenness can be locked to each other and fixed in position, or alternatively, a fan-shaped notch can be formed in the circumferential direction of the notch and the lid. By positioning and fixing the lid and the inner or outer ring by fitting the lid to the inner or outer ring, the lid is not affected by gaps due to component tolerances and is more Accurate and reproducible positioning and fixing of the lid in the radial direction is achieved, and by combining the uneven shape of the contact surface between the assembly hole and the lid and the fan-shaped shape of the assembly hole and the lid, it is possible to position and fix the lid in the radial direction either inside or outside. Another object of the present invention is to provide a cross roller bearing characterized by enabling more reliable and accurate positioning and fixing.

This invention provides an outer ring having a first raceway surface having a V-shaped cross section on an inner circumferential surface, extending in the circumferential direction and having an relief groove at the center; an inner ring having a second raceway surface extending in the circumferential direction and having an relief groove in the center and rotatable relative to the outer ring; provided on an end face of one of the inner ring and the outer ring in the axial direction; A plurality of rollers are disposed to intersect each other in a raceway formed by the first raceway surface and the second raceway surface through a built-in hole, and block the built-in hole and form the raceway path in the built-in hole. In a cross roller bearing consisting of a lid having a third raceway surface,
The assembling hole includes a first notch that is formed to extend in a radial direction from either the inner peripheral surface or the outer peripheral surface of the end surface of the inner ring, and that forms a contact surface with the lower surface of the lid; a second notch extending to the other of the inner circumferential surface and the outer circumferential surface formed by a notch step formed in the middle of the first notch or in the middle of the side surface of the installation hole;
The lid includes a convex step that fits into the first notch and the second notch of the assembling hole, and also locks and fits into the notch step. The cross roller is characterized in that the lid is moved in the radial direction by fitting the lid into the assembling hole and locking the convex step portion of the lid to the notch step portion, thereby positioning and fixing the lid. Regarding bearings. Further, in this cross roller bearing, one of the first notch and the second notch is deeper in the axial direction or longer in the radial direction than the other.

Alternatively, the present invention provides an outer ring having a first raceway surface having a V-shaped cross section on an inner circumferential surface, extending in the circumferential direction and having an relief groove in the center; An inner ring having a V-shaped second raceway surface extending in the circumferential direction and having an relief groove in the center and rotatable relative to the outer ring, provided on one end face in the axial direction of the inner ring and the outer ring. A plurality of rollers are disposed to intersect with each other through a built-in hole in the raceway formed by the first raceway surface and the second raceway surface, and a plurality of rollers are arranged to cross each other through the built-in hole, and the trackway in the built-in hole is closed. In a cross roller bearing consisting of a lid with a third raceway surface forming
The assembling hole includes a third notch that is formed to extend in the radial direction from either the inner peripheral surface or the outer peripheral surface of the end surface of the outer ring, and that forms a contact surface with the lower surface of the lid; a fourth notch extending to the other of the inner circumferential surface and the outer circumferential surface formed by a notch step formed in the middle of the third notch or in the middle of the side surface of the assembly hole;
The lid includes a convex stepped portion that fits into the third notch and the fourth notched portion of the assembling hole, and also locks and fits into the notched stepped portion, and The cross roller is characterized in that the lid is moved in the radial direction by fitting the lid into the assembling hole and locking the convex step portion of the lid to the notch step portion, thereby positioning and fixing the lid. Regarding bearings. Further, in this cross roller bearing, one of the third notch and the fourth notch is deeper in the axial direction or longer in the radial direction than the other.

Alternatively, the present invention provides an outer ring having a first raceway surface having a V-shaped cross section on an inner circumferential surface, extending in the circumferential direction and having an relief groove in the center; An inner ring having a V-shaped second raceway surface extending in the circumferential direction and having an relief groove in the center and rotatable relative to the outer ring, provided on one end face in the axial direction of the inner ring and the outer ring. A plurality of rollers are disposed to intersect with each other through a built-in hole in the raceway formed by the first raceway surface and the second raceway surface, and a plurality of rollers are arranged to cross each other through the built-in hole, and the trackway in the built-in hole is closed. In a cross roller bearing consisting of a lid with a third raceway surface forming
The built-in hole has a side surface that is a tapered surface extending in a first fan shape, the length of which is larger in the circumferential direction on either the inner circumferential side or the outer circumferential side of the inner ring or the outer ring. 5 notches,
The lid is formed in a second sector shape that fits into the fifth notch of the installation hole, and the movement of the lid in the radial direction is such that the second sector shape of the lid fits into the fifth notch of the installation hole. The present invention relates to a cross roller bearing characterized in that it is positioned and fixed by fitting into a fifth notch. Further, in the cross roller bearing, the fifth notch forming the assembly hole is formed to extend in a radial direction from either the inner circumferential surface or the outer circumferential surface of the end surface of the inner ring, and is formed in the lid. The inner peripheral surface and the outer periphery are formed by a first notch portion forming a contact surface with the lower surface, and a notch step portion formed halfway through the first notch portion or halfway along a side surface of the assembly hole. and a second notch extending to either one of the surfaces, and the lid has a convex step that locks and fits into the notch step formed in the fifth notch. It is equipped with a section. Alternatively, the fifth notch forming the assembly hole is formed to extend in a radial direction from either an inner circumferential surface or an outer circumferential surface of the end surface of the outer ring, and has a contact surface with the lower surface of the lid. the other of the inner circumferential surface and the outer circumferential surface formed by a third notch to be formed and a notch step formed in the middle of the third notch or in the middle of the side surface of the built-in hole; a fourth notch portion extending up to the fifth notch portion, and the lid includes a convex step portion that locks and fits into the notch step portion formed in the fifth notch portion. It is.

Further, in this cross roller bearing, the lid is fitted into the assembly hole and fixed to the inner ring or the outer ring in the axial direction with a pin or a screw.

As described above, the cross roller bearing according to the present invention has a complementary uneven notch step formed in the contact portion between the lid and the assembly hole formed in the inner ring or outer ring, which is the bearing ring, and the notch step It is possible to accurately position and fix the assembly hole and the lid by aligning the parts with each other or by forming the assembly hole and the lid into a fan shape, and in this state, process the raceway surface of the lid and the inner ring or outer ring. can. Next, after removing the lid from the assembly hole and inserting the rollers into the raceway, when reinstalling the lid, you can adjust the mounting position during machining without being affected by dimensional differences in the mounting holes, pins, screws, etc. Because it can be accurately reproduced, there is no step difference in the raceway surface between the inner ring or outer ring and the lid, and the rollers do not catch when rolling, improving rotation accuracy and providing a bearing with less noise and abnormal noise. be able to. Further, with this cross roller bearing, accurate positioning can be performed without using positioning pins, so it is possible to reduce the number of parts and reduce costs.

FIG. 1 is a plan view showing a first embodiment of a cross roller bearing according to the present invention. FIG. 2 is a partial perspective view of the cross roller bearing of FIG. 1 showing a state in which an assembly hole for loading rollers into a raceway is closed with a lid. FIG. 2 is a cross-sectional view showing the cross roller bearing along line AA in FIG. 1. FIG. FIG. 3 is a partial perspective view showing the mounting hole in the cross roller bearing shown in FIG. 2 with a lid removed from the mounting hole. The region of the assembly hole formed in the inner ring of this cross roller bearing is shown, (a) is a partial plan view showing a state in which the lid is removed from the cross roller bearing, and (b) is a partial plan view taken along line segment BB in (a). It is a sectional view showing a state. FIG. 7 is a perspective view showing a lid for closing the installation hole in this cross roller bearing, and showing an example in which an arcuate notch step is provided on the lower surface of the lid that contacts the contact surface of the installation hole. FIG. 7 is a perspective view showing a second embodiment of a lid for closing the installation hole in this cross roller bearing, in which a straight notch step is provided on the lower surface of the lid that contacts the contact surface of the installation hole. FIG. 7 is a cross-sectional view showing a modification of this cross roller bearing in which the assembly hole for loading the rollers into the raceway is closed with a lid provided with stepped notches extending in different directions. FIG. 7 is a partial perspective view showing another shape of the assembly hole in the cross roller bearing according to the present invention. FIG. 9 shows a sector-shaped lid that fits into the installation hole provided in the inner ring of the cross roller bearing shown in FIG. FIG. 10 is an explanatory diagram showing a state in which the lid in FIG. 9A is fitted into the installation hole shown in FIG. 9; FIG. 3 is a perspective view showing a fan-shaped lid that fits into an assembly hole provided in the outer ring of this cross roller bearing, and shows the lid that comes into contact with a contact surface of the assembly hole, viewed from below. This cross roller bearing shows a lid that fits into the installation hole, and (a) is a perspective view from below of the fan-shaped lid that fits into the inner ring and has a straight notch step. b) is a perspective view from below of a fan-shaped lid that fits on the inner ring and has an arc-shaped notch step, and (c) is a perspective view of a fan-shaped lid that fits on the outer ring and has a straight (d) is a perspective view from below of a lid having a stepped notch in the shape of a circular arc; It is a diagram. This cross roller bearing shows a lid that fits into the built-in hole, and (a) is a fan-shaped lid that fits into the inner ring, with the direction regulated by the tapered side surface and the direction regulated by the notch step. (b) is a perspective view from below of a lid with a straight notch stepped portion in which the directions are opposite; FIG. 2 is a perspective view of a lid having an arcuate notch step in which directions regulated by the notch step are opposite to each other when viewed from below. 1 shows an assembly hole in this cross roller bearing, and (a) is a plan view showing an example of an assembly hole provided in the inner ring, in which a locking portion serving as a step is provided on a side surface of the assembly hole, that is, a circumferential contact surface; (b) is a plan view showing another example of an assembling hole provided in the outer ring, in which a locking portion serving as a stepped portion is provided on a side surface of the assembling hole, that is, a circumferential contact surface. This cross roller bearing shows an assembly hole, and (a) is a tapered assembly hole provided in the inner ring, and is another embodiment in which a locking portion serving as a step is provided on the side surface of the assembly hole, that is, the circumferential contact surface. and (b) is a plane view showing yet another embodiment in which a tapered assembly hole is provided in the outer ring and a locking portion serving as a step is provided on the side surface of the assembly hole, that is, the circumferential contact surface. It is a diagram.

Hereinafter, one embodiment of a cross roller bearing according to the present invention will be described with reference to the drawings. The cross roller bearing according to the present invention can be applied to rotating parts, swing parts, etc. of mechanical devices such as robots such as industrial robots, optical equipment, medical equipment, and machine tools, and can be constructed compactly and thinly, and is lightweight and easy to handle. , can be operated easily.

First, a first embodiment of a cross roller bearing according to the present invention will be described with reference to FIGS. 1 to 6. This cross roller bearing generally includes an outer ring 1 having a raceway surface 11 (first raceway surface) having a V-shaped cross section and a relief groove 15 in the center on an inner peripheral surface 6, and an outer ring 1 opposite to the raceway surface 11 of the outer ring 1. An inner ring 2 which has a raceway surface 12 (second raceway surface) having a V-shaped cross section and an relief groove 16 in the center on the surface 9 and is rotatable relative to the outer ring 1, provided on the end surface 14 of the inner ring 2. Cylindrical rollers 4 are disposed to intersect with each other in a raceway 10 composed of a raceway surface 11 and a raceway surface 12 through the installation hole 5, and the rollers 4 block the installation hole 5 and form a raceway path 10 in the installation hole 5. It is composed of a lid 3 having a raceway surface 23 (third raceway surface). The outer ring 1 and the inner ring 2, which are raceway rings, are, for example, made by grinding a material to have outer circumferential surfaces 7 and 9 which are the outer diameter, inner circumferential surfaces 6 and 8 which are the inner diameter, and a raceway surface 11 which is the raceway groove. 12 are formed. In the first embodiment, an assembly hole 5 for assembling or loading the roller 4 into the raceway 10 is formed by notches 17 and 19 in the inner ring 2 by a processing method such as grinding. The notches 17 and 19 reach from the inner peripheral surface 6 to the outer peripheral surface 9 of the inner ring 2 in the radial direction of the cross roller bearing, and the axial depth of the assembly hole 5 is the center of the two raceway surfaces 12 of the inner ring 2. It is formed in a shape that reaches a clearance groove 16 which is provided at the connection part of the raceway surface and serves as a clearance for grinding the raceway surface. When the inner ring 2 and the outer ring 1 are combined, a raceway 10 is formed consisting of four raceway surfaces 11 and 12, and the opening 31 into which the rollers 4 can be loaded or inserted is a notch formed in the inner ring 2. 17 and 19. In this cross roller bearing, an inner ring 2 and an outer ring 1 are assembled, and then a lid 3 is removed from the inner ring 2, and a plurality of rollers 4 are inserted into a raceway 10 through an opening 31 of an assembly hole 5 formed by a notch 17. Insert. Next, the lid 3 is fitted into the assembly hole 5 of the inner ring 2, and finally, the screw 27 is inserted into the mounting hole 28 of the lid 3, the screw 27 is screwed into the screw hole 29 of the inner ring 2, and the lid 3 is inserted. is fixed to the inner ring 2.

This cross roller bearing is particularly designed with respect to an assembly hole 5 formed in either the outer ring 1 or the inner ring 2, that is, the outer ring 1 or the inner ring 2, and a lid 3 that closes the assembly hole 5, that is, fits into the assembly hole 5. It has characteristics. In the first embodiment, as shown in FIGS. 1 to 5 and 6, installation holes 5 for installing the rollers 4 into the raceway 10 are formed in the inner ring 2. The assembly hole 5 has a notch 17 (first notch) formed on the end surface 14 of the inner ring 2, which is a flat contact surface 18 extending from the inner circumferential surface 8 to the outer circumferential surface 9, as shown in FIGS. 4 and 5. , and a notch 19 (second notch) that reaches the clearance groove 16 in the outer peripheral surface 9 of the inner ring 2 by an arcuate notch step 20 formed in the middle of the notch 17 . In other words, the notches 17 and 19 of the inner ring 2 constituting the assembly hole 5 are formed by spaced apart opposing side surfaces 25 that extend substantially in parallel in the radial direction. In the first embodiment, the axial contact surfaces of the lid 3 and the notches 17, 19 of the inner ring 2 generally include a convex step formed on the lid 3 to restrict radially inward movement of the lid 3. The portion 21 and the notch stepped portion 20 formed in the inner ring 2 are configured to have an uneven shape and engage with each other. The circumferential width of the notches 17 and 19 on the raceway surface 12 side is slightly larger than the diameter and length of the roller 4 so that the roller 4 can be inserted therein. In addition, the lid 3 that is fitted into the assembly hole 5 in order to close the assembly hole 5 has a lower surface 22 that contacts the flat contact surface 18 of the assembly hole 5, and a part of the lower surface 22 that is engaged with the notch step 20. It is formed in a convex step portion 21 protruding from the top. That is, the lid 3 disposed in the notches 17 and 19 of the inner ring 2 is moved radially inward as the convex step 21 of the lid 3 engages the notch step 20 of the inner ring 2. will be regulated. Furthermore, the notch 19 formed in the inner ring 2 and the convex step 21 formed in the lid 3 extend in the circumferential direction relative to the flat contact surface 18. With the above configuration, when attaching the lid 3, it is possible to press the convex step 21 of the lid 3 inwardly against the notch step 20 of the inner ring 2 and fix the screw 27 with no gap. can. Therefore, when loading the rollers 4 into the raceway 10 from the installation hole 5, the lid 3 is removed from the inner ring 2, and after loading the rollers 4 into the raceway 10, the removed lid 3 is positioned in the installation hole 5 and reinstalled. When doing so, the lid 3 can be properly positioned and attached to the assembly hole 5 again. Further, even if an external force such as an excessive moment is applied to the cross roller bearing and a large load is applied to the rollers 4, the lid 3 will not shift inward in the radial direction.

Further, in this cross roller bearing, a screw hole 29 is provided in the notch 17 to which a screw 27 for fixing the lid 3 is attached. The lid 3 is fitted with a pin or screw 27 which is positioned by fitting into the assembly hole 5 and which is inserted through a mounting hole 28 formed in the lid 3 and screwed into a screw hole 29 formed in the inner ring 2. It is fixed to the inner ring 2. The lid 3 is formed in such a shape that a lower surface 22 serving as a contact surface matches the shape of the notches 17 and 19, and has a raceway surface 23 that is continuous with the raceway surface 12 of the inner ring 2 and has no step. The notches 17 and 19 are formed by cutting with an end mill or the like or by electrical discharge machining. Further, in order to fix the lid 3 to the inner ring 2 with a screw 27, a mounting hole 28 through which the screw 27 is inserted is provided at a position corresponding to the screw hole 29 of the inner ring 2. The radial width of the lid 3 is slightly larger than the radial width of the inner ring 2. In addition, with the lid 3 fitted into the notches 17 and 19 of the inner ring 2 and fixed with screws 27, the lid 3 is integrated with the inner ring 2, and the outer circumferential surface 32 and raceway surface 23 are simultaneously subjected to finish grinding. ing. Since the lid 3 is formed to be slightly larger than the installation hole 5 of the inner ring 2, in the above process, the portion protruding from the installation hole 5 is removed, so that the raceway surface 12 and the outer shape of the lid 3 and the inner ring 2 are continuous. It is formed without any steps.

Further, regarding the cross roller bearing according to the present invention, an embodiment in which a mounting hole 5 is formed in the inner ring 2 has been described above, but even if the mounting hole 5 is formed in the outer ring 1, although not shown, the same effect can be obtained. effect can be obtained. A case in which the assembly hole 5 is formed in the outer ring 1 will be briefly described here. That is, in the embodiment in which the assembly hole 5 is formed in the outer ring 1 in this cross roller bearing, the assembly hole 5 is generally formed of a flat contact surface extending from the inner circumferential surface 6 to the outer circumferential surface 7 on the end surface 39 of the outer ring 1. A notch (fourth notch) that reaches the escape groove 15 of the inner circumferential surface 6 of the outer ring 1 by a notch (third notch) and an arcuate notch step formed in the middle of the notch. It is formed by a notch). In other words, both notches of the outer ring 1 forming the assembly hole 5 are formed by spaced apart opposing side surfaces 25 extending substantially in parallel in the radial direction. In this embodiment, the axial contact surfaces of both the notches of the lid 3 and the outer ring 1 generally include a convex step formed on the lid 3 that restricts the radially outward movement of the lid 3. The outer ring 1 is configured to engage with a notch stepped portion formed in the outer ring 1 in an uneven shape.

Next, FIG. 7 shows a second embodiment of the lid 3 applied to this cross roller bearing. In the lid 3A of the second embodiment, the convex stepped portion 21 of the lid 3 of the first embodiment is formed in an arc shape in the width direction, whereas it extends straight in the width direction of the lid 3A. . The second embodiment has substantially the same configuration as the first embodiment, except that the assembly hole (not shown) formed in the inner ring 2 is formed in a shape corresponding to the lid 3A. . Further, in the second embodiment, the assembly hole (not shown) formed in the inner ring 2 has a shape into which the lid 3A fits, that is, the notch step formed in the inner ring 2 extends in a straight shape. Of course, it will be done.

Further, FIG. 8 shows a modification of the cross roller bearing in which the shapes of the assembly hole 5 and the lid 3 formed in the inner ring 2 are different from those shown in FIG. 3. Notches 36 and 37 formed in the inner ring 2 shown in FIG. 8 are different from notches 17 and 19 formed in the inner ring 2 shown in FIG. A notch 36 is formed deeper than the notch 37 and extends in the opposite direction. In this embodiment, the force applied to the mounting hole 5 of the inner ring 2 and the notched stepped portion 35 of the lid 3 is configured to restrict outward movement in the radial direction. Therefore, even if the inner ring 2 rotates, the lid 3 is locked by the notch step 35 and is prevented from flying out toward the trackway 10 due to centrifugal force. In this embodiment, for example, when manufacturing this cross roller bearing, with the lid 3 attached to the inner ring 2, the raceway surface 12 of the inner ring 2 and the raceway surface 23 of the lid 3 are integrated and simultaneously ground, and then , when removing the lid 3 from the inner ring 2 and inserting a plurality of rollers 4 through the installation hole 5, and fitting the lid 3 into the installation hole 5 of the inner ring 2 again after loading the rollers 4, the notch 36 and The lid 3 is positioned by pressing against the step of the notch step 35 at the boundary with the notch 37 and fixed with the screw 27, so that the lid 3 can be accurately fitted into the assembly hole 5 of the inner ring 2. .

Next, a third embodiment of the cross roller bearing according to the present invention will be described with reference to FIGS. 9 and 10. The cross roller bearing of the third embodiment differs from that of the first embodiment in that the shape of the assembly hole 5A and the lid are fan-shaped. FIG. 10 shows a lid 3B that fits into a mounting hole 5A in a cross roller bearing according to the present invention. The assembly hole 5A is formed in the inner ring 2. The assembly hole 5A is formed in a tapered surface 13 having a fan shape (first fan shape) in which the outer circumferential side of the inner ring 2 has a longer width in the circumferential direction than the inner circumferential side. The tapered surface 13 is formed such that the opposing side surface 25 is tapered from the outer circumferential side to the inner circumferential side, and the tapered surface 30 of the opposing side surface 24 of the lid 3B is aligned with the tapered surface 13 of the installation hole 5A. has been done. Further, the lid 3B is formed into a tapered surface 30 having a fan shape (second fan shape) with the outer peripheral side having a longer width in the circumferential direction than the inner peripheral side, corresponding to the shape of the installation hole 5A. Further, the side surface 24 (tapered surface 30) of the lid 3B and the side surface 25 (tapered surface 13) of the assembling hole 5A form surfaces that contact each other, and the cut of the assembling hole 5A is a tapered surface 13 that widens with each other. A notch 17T (fifth notch) is formed. In other words, since the circumferential width of the outer circumferential surface 9 of the built-in hole 5A is larger than the circumferential width of the inner circumferential surface 8 and is formed into a fan shape, the circumferential width is narrower inward in the radial direction. The movement of the lid 3B is restricted, and the fitting between the tapered surface 30 of the lid 3B and the tapered surface 13 of the installation hole 5A constitutes a locking portion, achieving the same effect as in the first embodiment. Furthermore, when a load is applied radially inward to the lid 3B, the side surface 25, which is the tapered surface 13, can receive the load. In the third embodiment, the side surface 25, which is the tapered surface 13 of the assembly hole 5A, is formed in a fan shape in which the circumferential width on the outer circumferential side of the inner ring 2 is larger than the circumferential width on the inner circumferential side. is formed into a fan shape by fitting into the fan shape of the assembling hole 5A, and by fitting the lid 3B into the assembling hole 5A of the inner ring 2, a locking portion 34 is formed in both fan shapes, and the inner ring 2, the lid 3B is positioned and fixed.

Although not shown, the lid 3C shown in FIG. 11 fits into an assembly hole formed in the outer ring 1. A lid 3C shown in FIG. 11 closes an assembly hole (not shown) provided in the outer ring 1, and has a tapered surface 30 with a side surface 24 extending in a substantially radial direction. Further, the entire lower surface 22 of the lid 3C is formed into a flat surface. The side surface 24 of the lid 3C has an inner peripheral surface 33 formed into a tapered surface 30 that is larger in the circumferential direction than the outer peripheral surface 32, and the lid 3C has a structure that restricts the outward movement of the outer ring 1 in the radial direction. Therefore, even if loaded by the rollers 4 of the rolling elements, the position is fixed relative to the outer ring 1, and there is no difference in level between the raceway surface 11 of the outer ring 1 and the raceway surface 23 of the lid 3C, and the raceway surface Noise caused by the step can be suppressed by the rollers 4 rolling on the rollers 11 and 23.

Regarding this cross roller bearing, as shown in FIGS. 12(a) to 12(d), the lids 3D to 3G have a configuration that combines the first to third embodiments, that is, the lids 3D to It is possible to simultaneously provide positioning in the radial direction by a step between the lower surface 22 of the 3G and a notch (not shown) of the inner ring 2 or the outer ring 1. Although not shown, the assembly hole includes a notch portion extending from the inner circumferential surface to the outer circumferential surface of the end surface 14 of the inner ring 2 or the end surface of the outer ring 1 to serve as a contact surface, and a notch portion formed in the middle of the notch portion. The lids 3D to 3G are formed by a cutout extending from the cutout step to the outer circumferential surface, and the lids 3D to 3G fit into the cutout of the installation hole and are locked to the cutout step. Of course, it is formed to include a convex stepped portion that fits together. The lid 3D and the lid 3E are used for the installation hole formed in the inner ring 2, and the lid 3F and the lid 3G are used for the installation hole formed in the outer ring 1. The lids 3D, 3E applied to the inner ring 2 and the lids 3F, 3G applied to the outer ring 1 have fan-shaped shapes extending in opposite directions, so that even when loaded by the rollers 4 rolling on the raceway 10, the locking portions do not stop. 34, it is positioned and fixed in the installation hole. In the lid 3D shown in FIG. 12(a), the side surface 24 extending in the substantially radial direction is formed into a tapered surface 30. Specifically, regarding the lower surface 22 of the lid 3D, the flat notch step portion 20 has a convex step portion 21 formed in a straight stepped shape. In the lid 3E shown in FIG. 12(b), the side surface 24 extending approximately in the radial direction is formed into a tapered surface 30, and the flat notch step 20 on the lower surface 22 of the lid 3E has an arc-shaped side surface 24. A convex stepped portion 21 is formed in a stepped shape. The lid 3F shown in FIG. 12(c) is a lid that closes the assembly hole provided in the outer ring 1, and has a tapered surface 30 with a side surface 25 extending approximately in the radial direction. Further, regarding the lower surface 22 of the lid 3F, the flat notch step portion 20 is formed with a convex step portion 21 in a straight stepped shape. A lid 3G shown in FIG. 12(d) is a lid that closes an assembly hole (not shown) provided in the outer ring 1, and has a tapered surface 30 with a side surface 24 extending approximately in the radial direction. Further, regarding the lower surface 22 of the lid 3G, the flat notch step portion 20 is formed with a convex step portion 21 having an arcuate stepped shape.

Regarding the lids 3D to 3G shown in FIGS. 12(a) to 12(d), as described above, the positioning of the tapered surface 30 of the side surface 24 extending in the radial direction and the alignment of the lower surface 22 of the lids 3D to 3G with the assembly hole are By positioning the notches and the steps, the lids 3D to 3G can be accurately and reliably positioned in the installation holes, and the locking part 34 can function effectively. That is, when the assembly hole is formed in the inner ring 2, the fan-shaped shape is opened radially outward to restrict the radially inward movement of the lids 3D to 3G, and the assembly hole is formed in the outer ring 1. If formed, the fan-shaped shape is opened radially inward to restrict the outward movement of the lids 3D to 3G in the radial direction. Furthermore, the level difference in the contact surface between the lids 3D to 3G and the notch of the assembling hole of the inner ring 2 or outer ring 1 is such that when the assembling hole is formed in the inner ring 2, the notch is shallower on the inside in the radial direction, and If the outside in the radial direction is set to be deep to restrict movement to the inside in the radial direction, and if a built-in hole is formed in the outer ring 1, the inside in the radial direction is deep and the outside in the radial direction is shallow to restrict movement in the radial direction. It is set to restrict movement to. Furthermore, movement in the direction of the end surface 14 of the inner ring 2 or in the direction of the end surface of the outer ring 1 is achieved by screwing screws 27 or the like into the inner ring 2 or outer ring 1 through the mounting holes 28 formed in the lids 3D to 3G. This allows precise and reliable positioning in all directions: radial, circumferential, and axial.

Next, lids 3H and 3J shown in FIGS. 13(a) and 13(b) are modified examples of lids 3D and 3E shown in FIGS. 12(a) and 12(b). Tapered surfaces 30 extending from the inside to the outside extend in opposite directions. That is, in comparison with the lid 3D shown in FIG. 12(a), the lid 3H shown in FIG. 13(a) has a side surface 24 extending in a substantially radial direction that is tapered in a direction opposite to the tapered surface 30 in FIG. 12(a). It is formed on the surface 30. Further, regarding the lower surface 22 of the lid 3H, the flat notch step portion 20 is formed with a convex step portion 21 in a straight stepped shape. Therefore, the lid 3H is positioned and fixed in both radially inward and radially outward directions. Similarly, in the lid 3J shown in FIG. 13(b), when compared with the lid 3E shown in FIG. 12(b), the side surface 24 extending approximately in the radial direction extends in the opposite direction to the tapered surface 30 in FIG. 12(b). It is formed on the tapered surface 30. Moreover, regarding the lower surface 22 of the lid 3J, the flat notch step portion 20 is formed with a convex step portion 21 having an arcuate stepped shape. Therefore, the lid 3J is positioned and fixed in both radially inward and radially outward directions.

Next, with reference to FIGS. 14(a) and 14(b), another embodiment of the assembling holes 5B and 5C formed in the inner ring 2 and outer ring 1 constituting the cross roller bearing according to the present invention will be described. In this cross roller bearing, the step between the contact surface between the lid 3 and the mounting holes 5B and 5C is not only provided on the contact surface in the axial direction as in the above embodiment, but also as shown in FIGS. 14(a) and 14(b). As shown in FIG. 2, a notch stepped portion is formed on the circumferential contact surface, that is, the side surface 25, 26 of the notch 17 (first notch) formed in the assembly holes 5B, 5C formed in the inner ring 2 or outer ring 1. A portion 34 may also be provided. The lid 3 is formed with a locking portion that is a complementary convex stepped portion corresponding to the locking portion 34 formed on the side surfaces 25 and 26 of the cutout portion 17 formed in the installation holes 5B and 5C, Of course, the locking portions 34 engage with each other to position and fix the lid 3 in the radial direction. The assembly hole 5B shown in FIG. 14(a) is formed in the inner ring 2, and the locking part 34, which is a step, is provided on the circumferential contact surface, which is the side surface 25 of the assembly hole 5B. In the hole 5B, one side surface 25 of the inner ring 2 extends straight in a substantially radial direction, the other side extends straight with a stepped portion in which a locking portion 34 is formed, and the opposing side surfaces 25 extend parallel to each other. ing. Further, the assembly hole 5C shown in FIG. 14(b) is formed in the outer ring 1, and the locking portion 34, which is a step, is provided on the circumferential contact surface, which is the side surface 26 of the assembly hole 5C. . The notch 17 formed in the assembly hole 5C has one side surface 26 of the outer ring 1 extending straight in the substantially radial direction, and the other side extending straight with a step part in which the locking part 34 is formed, and facing The side faces 26 extend parallel to each other.

Next, referring to FIGS. 15(a) and 15(b), assembling holes 5D and 5E formed in the inner ring 2 and outer ring 1 constituting the cross roller bearing according to the present invention are formed in the inner ring 2 or the outer ring 1. The locking portions 34, which are stepped portions, are provided on the circumferential contact surfaces, ie, the side surfaces 25 and 26, which are the side surfaces 25 of the mounting holes 5D and 5E. The assembly hole 5D shown in FIG. 15(a) has a notch 17T formed in the inner ring 2, and the locking part 34, which is a step, is located on the periphery, which is the side surface 25 of the notch 17T of the assembly hole 5B. The notch 17 provided in the direction contact surface and formed in the assembly hole 5D extends approximately radially to the tapered surface 13 on one side of the side surface 25 of the inner ring 2, and has a locking portion 34 formed in the middle on the other side. The tapered surface 13 has a stepped portion, and the opposing side surfaces 25 extend toward each other in a divergent manner. Further, the assembly hole 5E shown in FIG. 15(b) is formed in the outer ring 1, and the locking portion 34, which is a step, is provided on the circumferential contact surface, which is the side surface 26 of the assembly hole 5E. . The assembly hole 5E has one of the side surfaces 26 of the outer ring 1 extending approximately radially to the tapered surface 13, and the other side extending to the tapered surface 13 with a stepped portion in which a locking portion 34 is formed, and the opposite side surface 26. extend into mutually divergent ends.

The cross roller bearing according to the present invention is suitable for use in the rotating parts of various devices such as industrial robots, measurement/inspection equipment, medical equipment, and optical equipment, which are equipped with rotating parts such as joints, rotating parts, and swinging parts that receive complex loads. It is preferable to incorporate and use it.

1 Outer ring 2 Inner ring 3, 3A to 3H, 3J to 3N Lid 4 Roller 5, 5A to 5E Assembly hole 6, 8, 33 Inner peripheral surface 7, 9, 32 Outer peripheral surface 10 Raceway 11 Raceway surface (first raceway surface)
12 Raceway surface (second raceway surface)
13, 30 Tapered surface 14, 39 End surface 15, 16 Relief groove 17, 17T, 19, 36, 37 Notch portion 18 Contact surface 20, 35 Notch step portion 21 Convex step portion 22 Bottom surface 23 Raceway surface (third raceway surface)
24, 25 Side 27 Screw

Claims (4)

an outer ring having a first raceway surface having a V-shaped cross section on an inner circumferential surface, extending in the circumferential direction and having an relief groove at the center; an inner ring having a second raceway surface that extends and has a relief groove in the center and is rotatable relative to the outer ring; A plurality of rollers are disposed to intersect each other in a raceway formed by the first raceway surface and the second raceway surface through a mounting hole provided in an end face, and a plurality of rollers are arranged to cross each other in a raceway path formed by the first raceway surface and the second raceway surface. A cross roller bearing comprising a lid having a third raceway surface forming the raceway,
The built-in hole has a side surface that is a planar tapered surface extending in a first fan shape, the length of which is larger in the circumferential direction on either the inner circumferential side or the outer circumferential side of the inner ring or the outer ring. formed by a fifth notch consisting of;
The lid is formed in a second fan shape that fits into the fifth notch of the assembly hole,
The cross roller bearing, wherein the cover is moved in the radial direction by being positioned and fixed by fitting the second fan shape of the cover into the fifth notch of the assembling hole. The fifth notch that forms the assembly hole is a first notch that extends in the radial direction from either the inner peripheral surface or the outer peripheral surface of the inner ring, and that forms a contact surface with the lower surface of the lid. a second notch extending to the other of the inner circumferential surface and the outer circumferential surface formed by the notch part and the notch step part formed in the middle of the first notch part or in the middle of the side surface of the assembling hole; and a notch part, and the lid includes a convex step part that locks and fits into the notch step part formed in the fifth notch part. The cross roller bearing according to item 1. The fifth notch that forms the assembly hole is a third notch that extends in the radial direction from either the inner peripheral surface or the outer peripheral surface of the outer ring, and that forms a contact surface with the lower surface of the lid. a fourth notch extending to the other of the inner circumferential surface and the outer circumferential surface formed by the notch portion and the notch step portion formed halfway in the third notch portion or in the middle of the side surface of the assembling hole; and a notch part, and the lid includes a convex step part that locks and fits into the notch step part formed in the fifth notch part. The cross roller bearing according to item 1. The cross roller bearing according to any one of claims 1 to 3, wherein the lid that fits into the assembly hole is fixed to the inner ring or the outer ring with a pin or a screw in the axial direction. .

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