JP2008232205A - Shaft coupling - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simpler structure and increase torque load capacity while keeping a function to prevent a trouble due to inclination of a rolling element, in a shaft coupling of a type for transmitting power via a cylindrical rolling element provided at a crossing position of guiding grooves vertically crossing with each other between two parallel shafts. <P>SOLUTION: Respective output plates 1a, 1b, an input plate 2, respective retainers 4a, 4b are arranged to be symmetric about a cross section of a longitudinal center of a roller 3 so that the roller 3 is not inclined by a force applied to the roller 3 by these members on power transmission. Both the output plates 1a, 1b are connected by a cylindrical connecting piece 1d, integrally molded with an outer circumferential edge part of the output plate 1a at a side, which bridges the input plate 2 and the respective retainer 4a, 4b. Hence, its structure becomes simpler than that of a conventional shaft coupling and the torque load capacity can be increased by increasing the number of rollers 3 and enhancing strength of the connection piece 1d. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a shaft coupling that couples two parallel shafts and transmits power between the two shafts.

A shaft joint that connects two shafts of a general mechanical device and transmits power from the drive side to the driven side has a different structure depending on the positional relationship between the two shafts to be connected. And those that are parallel to each other (and not concentric). As a shaft coupling for connecting two parallel axes, the applicant of the present invention transmits a power via a cylindrical rolling element arranged at a crossing position of guide grooves perpendicular to each other between the two parallel axes. The thing was proposed (refer patent document 1).
JP 2005-233233 A

  7 and 8 show an example of the above-described shaft coupling. The shaft coupling includes two input plates 51a and 51b that are connected to each other so as to be rotatable integrally with each other and constitute an input-side rotating member, an output plate (output-side rotating member) 52 sandwiched between both input plates 51a and 51b, and an output It comprises a plurality of rollers (cylindrical rolling elements) 53 incorporated so as to penetrate the plate 52, and two annular retainers 54a, 54b disposed between the input plates 51a, 51b and the output plate 52. The input plate 51a and the output plate 52 on one side have shaft portions 55 and 56 protruding from the center portions thereof, and the shaft portion 56 of the output plate 52 and the holding hole for the central hole 51c of the input plate 51b on the other side. The rotation axes of the input plates 51a and 51b and the output plate 52 are held parallel to each other through the inner periphery of the container 54b. 7 and 8 show the state where the input plates 51a and 51b and the output plate 52 are concentric for the sake of explanation. Normally, the rotational axes of the input side and the output side are shifted (eccentric). Used in.

  Each of the input plates 51a and 51b and the output plate 52 is provided with a plurality of guide grooves 57 and 58 so as to be orthogonal to the corresponding guide grooves at the corresponding position of the rotating member on the other side. The guide groove 58 penetrates in the plate axial direction. The rollers 53 are passed through the guide grooves 58 of the output plate 52 and the long holes 59 of the cages 54a and 54b, and the both ends are guided by the guide grooves 57 of the input plates 51a and 51b. It is incorporated at the intersection of the guide grooves 57 and 58. As a result, the rollers 53 pushed by the input plates 51a and 51b push the output plate 52 while rolling with the retainers 54a and 54b constrained to move in the plate radial direction so as to transmit power. It has become.

  In the conventional shaft coupling described above, the input plates 51a and 51b, the output plate 52, and the cages 54a and 54b are arranged symmetrically with respect to the cross section at the center in the longitudinal direction of the roller 53, which is a cylindrical rolling element. Even if force is applied to the roller 53 from these members during power transmission, no rotational moment is generated in the roller 53 to prevent the roller 53 from twisting (biting into the guide groove), and the joint operation is always performed. It is done smoothly.

  However, in order to connect both the input plates 51a and 51b so as to be integrally rotatable, a connecting pin 51d penetrating each of the retainers 54a and 54b is provided, and the output plate 52 has a shape that does not interfere with the connecting pin 51d. The structure of the part is complicated, and there is a problem that it takes time and effort to manufacture and assemble.

  Further, since it is necessary to dispose the rollers 53 so as not to interfere with the connecting pins 51d, the number of the rollers 53 is limited thereby, and there is a problem that the torque load capacity becomes small. Furthermore, since it is difficult to make the connecting pin 51d thicker in terms of space, the torque load capacity may be further reduced from the strength of the connecting pin 51d.

  An object of the present invention is to prevent a trouble caused by the inclination of a rolling element in a shaft coupling that transmits power via cylindrical rolling elements arranged at intersecting positions of guide grooves perpendicular to each other between two parallel axes. It is to simplify the structure and increase the torque load capacity while maintaining the function.

  In order to solve the above-described problems, the present invention integrates two plates in which one of two rotating members, whose rotating shafts are held parallel to each other and not concentric, is disposed at a position sandwiching the other rotating member. A shaft portion protruding from the central portion of the other rotating member is passed through the center hole of one of the plates, and is connected to each plate of the one rotating member and the other rotating member. Are provided so as to be orthogonal to the corresponding guide groove at the corresponding rotating member, the guide groove of the other rotating member is penetrated in the axial direction of the rotating member, and the guide grooves of the two rotating members intersect. A cylindrical rolling element that is passed through the guide groove of the other rotating member and is guided to roll at both ends in the guide groove of each plate of the one rotating member. Holding to restrict the movement of the rotating member in the radial direction Is provided symmetrically with respect to the cross-section at the center in the longitudinal direction of the rolling element, and the shaft coupling is configured to transmit power between the rotating members via the rolling elements. The structure connected with the connecting piece straddling the other rotating member and the cage was adopted.

  That is, both rotating members and the cage are arranged so that the force applied to the cylindrical rolling elements from these members during power transmission does not incline the rolling elements, and one of the rotating members and the cage is arranged at a position sandwiching the other rotating member. By connecting both plates of the rotating member with a connecting piece straddling the other rotating member and the cage, the structure becomes simpler and the number of rolling elements is increased and the strength of the connecting piece is increased compared to the conventional one described above. As a result, the torque load capacity can be increased.

  Here, if the two plates of the one rotating member are connected to each other at their outer peripheral edge portions, the load on the connecting piece is reduced, and the torque load capacity can be further increased.

  If the connecting piece is formed integrally with any one of the two plates of the one rotating member, the production and assembly can be performed more easily.

  As a means for connecting the two plates of the one rotating member with the connecting piece, any one of screw connection, pin connection, spline connection, welding, and caulking may be employed.

  Further, by rotating the rolling element with at least two members of the rotating member and the cage via a rolling bearing fitted on the outer periphery thereof, both rotating members of the rolling element at the time of eccentricity Further, the relative movement resistance with respect to the cage can be reduced, and the joint operation can be made smoother.

  Further, the guide groove of each plate of the one rotary member is not penetrated in the axial direction of the rotary member, the space between the plates of the one rotary member is closed with the connecting piece, and A boot having a membrane part that elastically deforms following the eccentricity of both rotating members is provided between the edge of the center hole and the outer periphery of the shaft part of the other rotating member, and holds the lubricant inside the joint. By preventing the entry of foreign matter from the outside, the boot can be made small and simple in structure. Therefore, as compared with the case where a boot covering the entire joint is provided, the boot can be easily manufactured and the cost can be reduced. In addition, since the boot is less likely to break due to the centrifugal force even at high speed rotation, setting the boot rigidity low will reduce the elastic restoring force of the boot at the time of eccentricity so that it will not become a joint operation resistance. can do.

  As described above, in the shaft coupling of the present invention, both the rotating members and the cage are arranged so that the cylindrical rolling element is not inclined, and the two plates of the one rotating member are placed on the other rotating member and the cage. Because it is connected with connecting pieces that straddle the cable, there is no risk of trouble due to the inclination of the rolling elements as in the conventional case, and the structure is simpler than the conventional one, increasing the number of rolling elements and connecting them. The strength of the piece can be increased to increase the torque load capacity.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 6. 1 to 3 show a first embodiment. The basic structure of this shaft coupling is such that the input side and the output side of the above-described conventional shaft coupling are reversed. That is, as shown in FIGS. 1 and 2, the shaft coupling is sandwiched between two output plates 1a and 1b and two output plates 1a and 1b that are connected to each other so as to be integrally rotatable and constitute an output-side rotating member. An input plate (input-side rotating member) 2, a plurality of rollers (cylindrical rolling elements) 3 incorporated so as to penetrate the input plate 2, and 2 arranged between the output plates 1 a and 1 b and the input plate 2. It comprises two annular cages 4a and 4b. The output plate 1a and the input plate 2 on one side have shaft portions 5 and 6 projecting from the respective central portions, and the shaft portion 6 of the input plate 2 is connected to the central hole 1c and the holding of the output plate 1b on the other side. The rotation plates of the output plates 1a and 1b and the input plate 2 are held in parallel with each other through the inner periphery of the container 4b. 1 and 2 show the state where the output plates 1a and 1b and the input plate 2 are concentric for the sake of explanation, but the rotational axes of the input side and the output side are usually shifted as will be described later ( Used in an eccentric state.

  The output plates 1a and 1b are integrally formed on the outer peripheral edge of the output plate 1a on one side, and are connected to the input plate 2 and the retainers 4a and 4b. The outer peripheral edge portions of the two are bolted at a plurality of positions in the circumferential direction so as to be integrally rotatable. As a means for connecting the output plates 1a and 1b with the connecting piece 1d, pin connection, spline connection, welding, caulking, and the like can be employed in addition to the screw connection as in this example.

  The output plates 1a and 1b and the retainers 4a and 4b are arranged at symmetrical positions with the input plate 2 in between. In addition, between the inner peripheral surface of the connecting piece 1d of both output plates 1a and 1b and the outer peripheral surface of the input plate 2 and each cage 4a and 4b, the inner peripheral surface of the other output plate 1b and the shaft of the input plate 2 Predetermined clearances are provided between the outer peripheral surface of the portion 6 and these members do not interfere with each other even when the input side and output side rotation shafts are eccentric as shown in FIG. Yes.

  Each of the output plates 1a, 1b and the input plate 2 is provided with a plurality of guide grooves 7, 8 for guiding the roller 3, and the retainers 4a, 4b pass through the roller 3 in the plate radial direction. A long hole 9 for restricting movement is provided.

  The guide grooves 7 of the output plates 1a and 1b are provided so that their circumferential positions coincide between the two plates and extend linearly in a direction that forms a certain angle with the plate radial direction. On the other hand, the guide groove 8 of the input plate 2 penetrates in the plate axial direction and is provided so as to extend linearly perpendicular to the guide groove 7 at the corresponding position of the output plates 1a and 1b. In this example, the guide grooves 7 of the output plates 1a and 1b are also penetrated in the plate axis direction for easy processing. Further, the long holes 9 of the cages 4a and 4b are provided at positions corresponding to the guide grooves 7 and 8 so as to extend linearly in a direction that forms 45 degrees with the guide grooves 7 and 8.

  Each of the rollers 3 passes through the guide groove 8 of the input plate 2 and the long hole 9 of each of the cages 4a and 4b, and is guided in the state where both ends are guided by the guide grooves 7 of the output plates 1a and 1b. The plates 1a, 1b, and 2 are in rolling contact with each other through rolling bearings 10 that are incorporated at the intersections of the grooves 7 and 8 and are fitted to the outer periphery of both ends and the center. The rolling bearing is not limited to the roller bearing as in this example, and a ball bearing may be used.

  This shaft coupling has the above-described configuration, and when the input plate 2 to which the input torque is applied rotates, the roller 3 pushed from the circumferential direction into the guide groove 8 of the input plate 2 is moved by the retainers 4a and 4b. Power is transmitted to the output side by pushing the guide grooves 7 of the output plates 1a and 1b and rotating both the output plates 1a and 1b integrally with the radial movement being constrained. Even if the rotation direction of the input torque is changed or the input side and the output side are reversed, power transmission is performed by the same mechanism.

  The power transmission mechanism is basically the same even in a normal use state in which the input and output rotation shafts are eccentric. In this state, as shown in FIG. 3, the crossing position of the guide grooves 7 and 8 changes in the circumferential direction of the plate due to the displacement of the rotation shafts of the output plates 1a and 1b and the input plate 2, and the rollers 3 7 and 8 and the power transmission is performed while moving inside the long holes 9 of the cages 4a and 4b.

  At the time of power transmission, each roller 3 is subjected to a force in the roller radial direction from each of the output plates 1a and 1b, the input plate 2 and the cages 4a and 4b. , The rotational moment is not generated in the roller 3. Accordingly, the guide grooves 7 and 8 are not easily bitten by the inclination of the roller 3, and the power can be transmitted smoothly.

  Further, each roller 3 is in rolling contact with each plate 1a, 1b, 2 via the rolling bearing 10 as described above, and since the resistance when moving relative to each plate 1a, 1b, 2 is small, The joint operation during eccentricity is also performed smoothly. In order to make the joint operation smoother, it is also possible to insert a rolling bearing in an intermediate portion between the central portion and both end portions of the roller so that the roller is brought into rolling contact with each cage via these bearings. Good.

  In addition, in this shaft coupling, both output plates 1a and 1b arranged at positions sandwiching the input plate 2 are connected by a connecting piece 1d straddling the input plate 2 and the cages 4a and 4b. Compared to the structure, it is easy to manufacture and assemble. Further, since there is no interference between the connecting piece 1d and the input plate 2 or the cages 4a and 4b, the number of rollers 3 is increased as compared to the conventional case, and the connecting piece 1d is shaped to obtain high strength, and the torque load capacity is increased. Can be made.

  FIG. 4 shows a second embodiment. In this embodiment, based on the first embodiment, the guide groove 7 of each output plate 1a, 1b is not penetrated in the plate axial direction, and the edge of the center hole 1c of the other output plate 1b and the input plate 2 are used. A boot 11 having a membrane portion that elastically deforms following the eccentricity of the output plates 1a and 1b and the input plate 2 is provided between the outer periphery of the shaft portion 6 of the first and second shaft portions 6. With these configurations and the cylindrical connecting piece 1d that closes the space between the output plates 1a and 1b, the entire joint is sealed, and the lubricant is held inside the joint, and foreign matter from the outside of the joint is removed. Intrusion can be prevented.

  In the above configuration, since the boot 11 is small and has a simple structure as compared with the case where a boot covering the entire joint is provided, the boot 11 can be easily manufactured and the cost can be reduced. In addition, since the boot 11 is less likely to break due to the centrifugal force even during high-speed rotation, by setting the rigidity of the boot 11 low, the elastic restoring force of the boot 11 at the time of eccentricity can be reduced and the resistance of the joint operation can be reduced. It can be avoided.

  5 and 6 show a third embodiment. In this embodiment, based on the first embodiment, the number of rollers is four, and the positional relationship between the input plate and the cage is reversed, that is, two input plates 12a constituting the input-side rotating member. , 12b are arranged at positions where one cage 13 is sandwiched. Both the input plates 12a and 12b can be integrally rotated by bolting a connecting piece 12c projecting inward from the central portion of the input plate 12b on the other side and the central portion of the input plate 12a on the one side. It is connected. Further, the position of the rolling bearing 10 fitted into the roller 3 is the same as that in the first embodiment, and the roller 3 is in rolling contact with each output plate 1a, 1b and the retainer 13 via each rolling bearing 10, and each input plate. 12a and 12b are in direct contact with each other.

Side view of the shaft coupling of the first embodiment Sectional view along the line II-II in FIG. The side view which shows the use condition of the shaft coupling of FIG. 1 (The figure except one input plate) Sectional drawing corresponding to FIG. 2 of the shaft coupling of 2nd Embodiment Side view of shaft coupling of third embodiment Sectional view along line VI-VI in FIG. Side view of conventional shaft coupling Sectional view along line VIII-VIII in FIG.

Explanation of symbols

1a, 1b Output plate 1c Center hole 1d Connecting piece 2 Input plate 3 Rollers 4a, 4b Cage 5, 6 Shaft 7, 8 Guide groove 9 Long hole 10 Rolling bearing 11 Boot 12a, 12b Input plate 12c Connecting piece 13 Cage

Claims (6)

  One of the two rotating members that are held in a state where the rotation axes are parallel to each other and not concentric connect two plates arranged at positions sandwiching the other rotating member so as to be integrally rotatable, and one of the plates The shaft portion protruding from the central portion of the other rotating member is passed through the center hole of the other rotating member, and a plurality of guide grooves are provided in the corresponding rotating member on the other side of each plate and the other rotating member of the one rotating member. The guide groove of the other rotary member is provided at a position where the guide groove of the other rotary member intersects with the guide groove of the other rotary member. A cage that is passed through a cylindrical rolling element that rolls while being guided at both ends in the guide groove of each plate of the one rotating member, and restrains the movement of each rolling element in the radial direction of the rotating member. The section in the longitudinal center of the rolling element In a shaft coupling that is provided symmetrically so that power is transmitted between the rotating members via the rolling elements, the plates of the one rotating member are connected across the other rotating member and the cage. A shaft coupling characterized by being connected by one piece.   The shaft coupling according to claim 1, wherein the two plates of the one rotating member are connected to each other at their outer peripheral edge portions.   The shaft coupling according to claim 1 or 2, wherein the connecting piece is integrally formed with any one of the two plates of the one rotating member.   4. The screw connection, pin connection, spline connection, welding, or caulking is adopted as means for connecting the two plates of the one rotating member with the connecting piece. The shaft coupling described in 1.   5. The rolling element according to claim 1, wherein the rolling element is brought into rolling contact with at least two members of the rotating members and the cage through a rolling bearing fitted on an outer periphery thereof. The shaft coupling described in 1.   The guide groove of each plate of the one rotary member is not penetrated in the axial direction of the rotary member, the connection piece closes the space between the plates of the one rotary member, and the central hole of the one plate A boot having a membrane portion that elastically deforms following the eccentricity of both rotating members is provided between the edge and the outer periphery of the shaft portion of the other rotating member to hold the lubricant inside the joint, and from the outside of the joint The shaft coupling according to any one of claims 1 to 5, wherein intrusion of foreign matter is prevented.

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