JP2006125498A - Axial one-way clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an axial one-way clutch with a rod movable in two directions and lockable in one direction as required. <P>SOLUTION: A cage 10 is energized toward a narrow portion of a wedge space 8 by an elastic member 11. The holding pin 13 with one end engaging with an engaging portion 14 provided at the end of the cage 10 holds a conical roller 9 in the state of facing a wide portion of the wedge space 8. A piston 22 is provided on the holding pin 13 so as to be slidable in a cylinder 21 provided on the outer periphery of a housing 1, and a cylinder lower chamber 23 provided in the cylinder 21 is communicated with a high pressure air source 24 via a passage 25. A solenoid selector valve 26 incorporated in the passage 25 is changed over to an operation position, the holding pin 13 is moved in the axial direction for disengaging from the engaging portion 14, and the conical roller 9 is bitten into the narrow portion of the wedge space 8 by the elastic member 11 to lock the rod 4 in one direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an axial one-way clutch which can prevent movement in one direction of a reciprocable rod as required.

Conventionally, an axial one-way clutch described in Patent Document 1 is known. In this axial one-way clutch, a tapered surface having a large-diameter end at the opening end is provided at an opening of a cylinder formed in the body, and a rear end portion is slidably inserted into the tapered surface and the cylinder. A ball and a cage for holding the ball are incorporated between the cylindrical surfaces on the outer periphery of the rod, and the ball is pressed against the tapered surface of the cylinder and the outer cylindrical surface of the rod by applying a spring force of the compression spring to the cage. When the pushing force is applied to the rod, the ball is engaged with the tapered surface of the cylinder and the outer cylindrical surface of the rod to lock the rod.
Japanese Patent Publication No. 56-53139

  By the way, in the one-way clutch in the axial direction described in Patent Document 1, the ball is in a standby state in which the ball is pressed against the tapered surface of the cylinder and the outer cylindrical surface of the rod by the spring force of the compression spring, and the pushing force is applied to the rod. If this is done, the ball will immediately engage and the rod cannot be moved in the pushing direction.

  As described above, the axial one-way clutch is configured to lock the rod in one direction and freely move the rod in the other direction, and cannot move the rod in both axial directions. It can be used only for special applications such as, and the application range is narrow. For example, the arm and foot of an industrial robot or the parking brake mechanism of an electric brake can move the rod in both directions and when necessary It is not possible to adopt it in devices that can lock the rod in one direction only.

  An object of the present invention is to provide an axial one-way clutch in which a rod is movable in both axial directions and can be locked in one direction when necessary.

  In order to solve the above-described problems, in the present invention, one end in the axial direction is narrow between the inner periphery of the housing that is fixedly arranged and the outer periphery of the rod that is inserted into the housing and is movable in the axial direction. A wedge-shaped space is formed, and an engagement element and a holder for holding the engagement element are incorporated in the wedge-shaped space, and the engagement element is directed toward a narrow portion of the wedge-shaped space by an elastic member. By urging toward the moving direction, penetrating the housing slidably in the radial direction, and by engaging one end portion facing the wedge-shaped space and an engaging portion provided at the end portion of the cage A holding pin for holding the retainer is provided in a disengaged state where the engaging element faces the wide portion of the wedge-shaped space, and the holding pin is urged toward the wedge-shaped space by the elastic member, and the electromagnetic switching valve The flow is controlled by operation. It had adopted a structure in which a moving means for moving radially outward of the housing holding pin as a drive source a high-pressure air.

  Here, the engagement element may be a tapered roller or a ball. Moreover, a cylindrical roller may be sufficient.

  Further, the moving means comprising the following (1) and (2) can be adopted.

  Moving means (1): a cylinder that is attached to the outer periphery of the housing and covers an outer end portion of the holding pin facing the outside of the housing, and a piston that is provided at the outer end portion of the holding pin and that can slide in the cylinder And a passage communicating with the high pressure air generation source in the cylinder lower chamber provided between the piston and the outer periphery of the housing, and a state where the cylinder lower chamber is communicated with the high pressure air generation source. Consists of an electromagnetic switching valve that selectively switches between states.

  Moving means (2): a lever having one end connected to an outer end facing the outside of the housing of the holding pin, and capable of swinging around a position offset from the center in the length direction to the other end, and the lever An air cylinder having the other end of the piston rod connected to the tip of the piston rod, a passage communicating with the cylinder upper chamber formed between the rod cover of the air cylinder and the piston, and a high-pressure air generating source, and is incorporated in the passage. And an electromagnetic switching valve that selectively switches between a state in which the cylinder upper chamber communicates with a high-pressure air generation source and a state in which the cylinder upper chamber communicates with the atmosphere.

  In the axial one-way clutch configured as described above, the engaging pin is engaged with the engaging portion of the cage end, and the engaging element is held at the disengaged position facing the wide portion of the wedge-shaped space. It can be moved in both axial directions. Further, when the holding pin is moved outward in the radial direction of the housing by the operation of the moving means using high-pressure air as the driving source, the engagement of the holding pin with the engaging portion is released, and the cage is wedged by the pressing of the elastic member. The engagement element moves toward the narrow portion of the wedge-shaped space and engages with the narrow portion of the wedge-shaped space, and the rod is prevented from being locked and moving in one direction. For this reason, the rod which can move to both directions can be locked to one direction as needed.

  Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show an embodiment of an axial one-way clutch according to the present invention. As shown in the figure, the housing 1 has a cylindrical shape, and an end plate 2 is integrally provided at one end, and an annular plate 3 is attached to an opening at the other end by means such as press fitting.

  The rod 4 inserted into the housing 1 is supported by a bearing 5 attached to the end plate 2 so as to be movable in the axial direction.

  A cylindrical surface 6 is provided on the outer periphery of the rod 4, while a cam surface 7 formed of a conical surface is formed on the inner periphery of the housing 1, and one end in the axial direction is provided between the cam surface 7 and the cylindrical surface 6. A narrow wedge-shaped space 8 is provided.

  Inside the wedge-shaped space 8, a plurality of tapered rollers 9 as engagement elements and a cage 10 that holds the tapered rollers 9 are incorporated. The retainer 10 is urged in a direction in which the tapered roller 9 moves toward the narrow portion of the wedge-shaped space 8 by an elastic member 11 incorporated between the retainer 10 and the annular plate 3.

  The housing 1 is provided with a radial pin hole 12 extending from the outer periphery to the narrow portion of the wedge-shaped space 8, and a holding pin 13 is slidably inserted into the pin hole 12.

  One end of the holding pin 13 facing the narrow portion of the wedge-shaped space 8 can be engaged with an engaging portion 14 formed of a notch formed on the outer periphery of the end of the retainer 10. The retainer 10 is held at the disengagement position where the tapered roller 9 is disengaged from the cylindrical surface 6 and the cam surface 7 by the engagement.

  Note that the end face of the cage 10 may be the engaging portion 14 and the cage 10 may be held at the disengaged position by the engagement of the holding pin 13 with the engaging portion.

  The holding pin 13 is urged toward the wedge-shaped space 8 by an elastic member 15 that presses the outer end surface thereof. The holding pin 13 is moved outward in the radial direction of the housing 1 by a moving means 20 that drives high-pressure air.

  The moving means 20 fixes a cylinder 21 coaxially with the holding pin 13 on the outer periphery of the housing 1, and the holding pin 13 is provided with a piston 22 slidable along the inner periphery of the cylinder 21. A cylinder lower chamber 23 formed between the outer peripheral surfaces of the housing 1 and a high-pressure air generation source 24 are communicated by a passage 25, and an electromagnetic switching valve 26 is incorporated in the passage 25. The elastic member 15 is incorporated.

  Here, the electromagnetic switching valve 26 comprises a three-port two-position switching valve. The cylinder lower chamber 23 communicates with the atmosphere at the normal position of the electromagnetic switching valve 26, and the cylinder lower chamber 23 and the high-pressure air generation source at the operating position. The high pressure air is supplied into the cylinder lower chamber 23 in communication with the cylinder 24.

  The axial one-way clutch shown in the embodiment has the above-described structure. FIG. 1 shows a state where the electromagnetic switching valve 26 is in the normal position, the cylinder lower chamber 23 communicates with the atmosphere, and the holding pin 13 is the elastic member 15. Accordingly, one end portion of the cage-shaped space 8 that is urged toward the wedge-shaped space 8 is engaged with the engaging portion 14 of the cage 10, and the cage 10 is engaged with the wedge-shaped space 8 by the engagement. The tapered roller 9 is held at a position disengaged from the cylindrical surface 6 and the cam surface 7.

  For this reason, the rod 4 is in a state of being movable in both axial directions (the right direction and the left direction in FIG. 1).

  In the state shown in FIG. 1, when the electromagnetic switching valve 26 is switched to the operating position, the cylinder lower chamber 23 communicates with the high pressure air generation source 24, and the high pressure air from the high pressure air generation source 24 is supplied into the cylinder lower chamber 23. Then, the piston 22 and the holding pin 13 move outward in the radial direction of the housing 1 against the elasticity of the elastic member 15, and the engagement between the holding pin 13 and the engaging portion 14 is released. By releasing the engagement, the retainer 10 is moved toward the narrow portion of the wedge-shaped space 8 by the pressing of the elastic member 11, and the tapered roller 9 is engaged with the cylindrical surface 6 and the cam surface 7 as shown in FIG. To do. For this reason, the rod 4 is locked and prevented from moving in one direction (the opposite direction indicated by the arrow in FIG. 3), and can move only in the direction indicated by the arrow in FIG.

  Thus, since the rod 4 can be locked in one direction by switching the electromagnetic switching valve 26 to the operating position, the rod 4 movable in both directions can be locked in one direction as required.

  To return the tapered roller 9 to the disengaged state, the rod 4 is moved in the direction of the arrow in FIG. 3 while the electromagnetic switching valve 26 is switched to the normal position and the cylinder lower chamber 23 is in communication with the atmosphere. The cage 10 is moved toward the wide portion of the wedge-shaped space 8 by the frictional resistance acting on the contact portion between the cylindrical surface 6 of the rod 4 and the tapered roller 9, and is moved toward the wedge-shaped space 8 by the pressing of the elastic member 15. One end of the biased holding pin 13 is engaged with the engaging portion 14.

  In order to reliably reset the cage 10 as described above, an actuator may be provided on the end plate 2 of the housing 1, and the actuator 10 may be pushed toward the wide portion of the wedge-shaped space 8 by the actuator. .

  In the embodiment, the tapered roller 9 is shown as the engaging element, but the engaging element is not limited to the tapered roller 9. For example, it may be a ball or a cylindrical roller. When the cylindrical roller is used as the engagement element, the cylindrical roller is disposed so that the axial center is orthogonal to the axial direction of the rod 4, and a pair of the inner periphery of the housing 1 and the outer periphery of the rod are opposed to each other in the radial direction of the housing 1. Are formed, and one of the pair of flat surfaces is inclined in the axial direction of the rod 4 to form a wedge-shaped space between the pair of flat surfaces.

  4 and 5 show another example of the moving means 20 that moves the holding pin 13 radially outward of the housing 1. In the moving means 20 shown in FIG. 4, one end of a lever 27 is connected to the end of the holding pin 13 inserted into the pin hole 12 of the housing 1 facing the outside of the housing 1, and the lever 27 is centered in the longitudinal direction. A position shifted from the other end to the other end side is supported by a support piece 28 provided on the outer periphery of the housing 1 through a support pin 29 so as to be swingable. The elastic member 30 supported by the support pin 29 supports the holding pin 13. The lever 27 is urged in a direction in which one end portion engages with the engaging portion 14 of the cage 10. An air cylinder 31 comprising a cylinder 32 and a piston 33 and a piston rod 34 incorporated in the cylinder 32 is attached to the outer periphery of the housing 1, and is formed between the rod cover of the air cylinder 31 and the piston 33. The cylinder upper chamber 35 and the high-pressure air generation source 36 are communicated with each other through a passage 37, an electromagnetic switching valve 38 is incorporated in the passage 37, and the other end of the lever 27 is connected to the tip of the piston rod 34. .

  Here, the electromagnetic switching valve 38 is composed of a three-port two-position switching valve. The cylinder upper chamber 35 communicates with the atmosphere at the normal position of the electromagnetic switching valve 38 and is switched to the operating position, whereby the cylinder upper chamber 35 has a high pressure. Air is supplied.

  In the moving means 20 configured as described above, the cylinder upper chamber 35 communicates with the atmosphere with the electromagnetic switching valve 38 positioned at the normal position, and one end of the holding pin 13 is engaged with the engaging portion 14 of the cage 10. In addition, the cage 10 is held in a state located in the wide portion of the wedge-shaped space 8.

  When the electromagnetic switching valve 38 is switched to the operating position, the high pressure air from the high pressure air generating source 36 is supplied to the cylinder upper chamber 35, the piston 33 and the piston rod 34 move toward the outer periphery of the housing 1, and the lever 27 is moved. The retainer pin 13 swings around the support pin 29 and moves outward in the radial direction of the housing 1. As shown in FIG. 5, the tapered roller 9 is engaged with the cylindrical surface 6 and the cam surface 7 by moving toward the narrow portion of the wedge-shaped space 8.

  Also in the adoption of the moving means 20, the rod 4 can be locked in one direction as required.

  In FIG. 4, the holding pins 13 and the air cylinders 31 are arranged in the axial direction of the housing 1, but the holding pins 13 and the air cylinders 31 may be arranged in the circumferential direction of the housing 1.

A longitudinal front view showing an embodiment of an axial one-way clutch according to the present invention Sectional view along the line II-II in FIG. Sectional drawing which shows the locked state of the one-way clutch shown in FIG. Longitudinal front view showing another example of moving means Sectional drawing which shows the locked state of the one-way clutch shown in FIG.

Explanation of symbols

1 housing 4 rod 8 wedge-shaped space 9 tapered roller (engagement element)
DESCRIPTION OF SYMBOLS 10 Cage 11 Elastic member 13 Holding pin 15 Elastic member 20 Moving means 21 Cylinder 22 Piston 23 Cylinder lower chamber 24 High pressure air generation source 25 Passage 26 Electromagnetic switching valve 27 Lever 31 Air cylinder 34 Piston rod 35 Cylinder upper chamber 36 High pressure air Source 37 Passage 38 Electromagnetic switching valve

Claims (4)

  A wedge-shaped space in which one end in the axial direction is narrowed is formed between the inner circumference of the fixed housing and the outer circumference of the rod that is inserted into the housing and is movable in the axial direction. An engaging member and a retainer for holding the engaging member, and the retainer is urged by an elastic member in a direction in which the engaging member moves toward a narrow portion of the wedge-shaped space, and the housing has a radius. Disengagement of the engaging element facing the wide part of the wedge-shaped space by engagement of one end part that slidably moves in the direction and facing the wedge-shaped space and the engaging part provided at the end part of the cage A holding pin for holding the cage is provided in the state, and the holding pin is urged toward the wedge-shaped space by an elastic member, and the high pressure air whose flow is controlled by the operation of the electromagnetic switching valve is held as a driving source. Pin the housing half Axial one-way clutch provided with moving means for moving in a direction outward.   The axial one-way clutch according to claim 1, wherein the engagement member is made of one of a tapered roller, a ball, and a cylindrical roller.   A cylinder attached to an outer periphery of the housing and covering an outer end portion of the holding pin facing the outside of the housing; a piston provided at an outer end portion of the holding pin and slidable in the cylinder; A passage communicating with the high pressure air generation source in the cylinder lower chamber provided between the piston and the outer periphery of the housing, a state where the cylinder lower chamber is connected to the high pressure air generation source, and a state where the cylinder lower chamber communicates with the high pressure air generation source. The axial one-way clutch according to claim 1 or 2, comprising an electromagnetic switching valve that selectively switches between the two.   The moving means has one end connected to the outer end facing the outside of the housing of the holding pin, and a lever swingable around a position shifted from the center in the length direction to the other end, and the lever An air cylinder having the other end connected to the tip of the piston rod, a passage communicating with the cylinder upper chamber formed between the rod cover of the air cylinder and the piston, and a high-pressure air generation source, are incorporated in the passage. The axial one-way clutch according to claim 1 or 2, comprising an electromagnetic switching valve that selectively switches between a state in which the cylinder upper chamber communicates with a high-pressure air generation source and a state in which the cylinder upper chamber communicates with the atmosphere.

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