JP2010133474A - Axial coupling device and torque limiter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an axial coupling device in which the frictional engagement between a cylindrical member and a shaft member is more certain and firm, and an axial end section of fluid pressure expansion chamber is hard to be damaged. <P>SOLUTION: A plurality of cylindrical hydraulic pressure expansion chambers 31, which axially exist in extension so as to locate with an axial space, are formed in a cylindrical member 1. Furthermore, based on a hydraulic pressure of oil filled in the hydraulic pressure expansion chamber 31, a cylindrical inner circumference surface 24 of the cylindrical member 1 is pressed to a cylindrical periphery surface 20 of a shaft member 2 through a cylindrical gripping section 43 of an annular member 3 by reducing in diameter a cylindrical inner circumference surface 24 of the cylindrical member 1. Additionally, in the gripping section 43, a radial wall thickness of a thin wall section 58, located between axially adjacent hydraulic pressure expansion chambers 31, is set to be smaller than a radial wall thickness of a thick wall section 59 overlapping radially in the hydraulic pressure chamber 31. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a shaft coupling device having a hydraulic expansion chamber, and to a torque limiter having a hydraulic expansion chamber.

Conventionally, as a shaft coupling device, there is one described in JP-A-5-296252 (Patent Document 1). The shaft coupling device includes a shaft member and a cylindrical member, and the cylindrical member has two annular hydraulic expansion chambers, and the two hydraulic expansion chambers are arranged in two rows at intervals in the axial direction. Has been placed. The shaft coupling device reduces the diameter of the inner peripheral surface of the cylindrical member with oil sealed in the two hydraulic expansion chambers and presses the reduced inner peripheral surface against the outer peripheral surface of the shaft member. Thus, the cylindrical member and the shaft member are frictionally engaged.
JP-A-5-296252 (FIG. 1)

  In such a background, in the shaft coupling device having a plurality of hydraulic pressure expansion chambers positioned at intervals in the axial direction, it is desirable to make the frictional engagement between the cylindrical member and the shaft member more reliable and strong. . In addition, it is desirable to further suppress damage to the hydraulic expansion surface that is the inner peripheral surface of the hydraulic expansion chamber to which excessive stress acts during friction engagement.

  Therefore, the problem of the present invention is that the frictional engagement between the cylindrical member and the shaft member is more reliable and strong, and the hydraulic expansion surface that is the inner peripheral surface of the hydraulic expansion chamber is damaged during the frictional engagement. It is to provide a difficult shaft coupling device.

  Moreover, the subject of this invention is providing a torque limiter provided with such a shaft coupling device.

In order to solve this problem, the shaft coupling device of the present invention includes:
A shaft member having an outer peripheral surface;
A cylindrical member having an inner circumferential surface opposed to the outer circumferential surface in the radial direction;
An annular member having an annular clamping portion sandwiched between the outer peripheral surface of the shaft member and the inner peripheral surface of the cylindrical member;
One of the shaft member and the cylindrical member is disposed at an axial interval from each other, and the peripheral surface of the one member is disposed between the shaft member and the cylindrical member via the clamping portion. A plurality of annular hydraulic expansion chambers having an annular hydraulic expansion surface that presses against the peripheral surface of the other member of
The clamping portion is fixed to the one member,
The clamping unit is configured so that the end of the hydraulic expansion chamber provided on the other side in the axial direction extends from the end on the one side in the axial direction of the hydraulic expansion surface of the hydraulic expansion chamber provided on the most one side in the axial direction. A thick portion with a thick radial thickness and a thicker radial portion than the thick portion in a range that overlaps the radial range to the axial range to the other end in the axial direction of the hydraulic expansion surface And a thin thin portion.

  According to the present invention, the annular clamping portion of the annular member is fixed to the one member, and is sandwiched between the outer peripheral surface of the shaft member and the inner peripheral surface of the cylindrical member. The other member does not come into contact with the hydraulic expansion surface that protrudes toward the other member due to the hydraulic pressure in the annular hydraulic expansion chamber formed in one member. For this reason, the hydraulic expansion surface is hardly twisted by the other member, friction is not easily generated, and damage to the hydraulic expansion surface can be suppressed.

  Then, in the clamping portion, from the end portion on one side in the axial direction of the hydraulic pressure expansion chamber provided on the most one side in the axial direction, on the other side in the axial direction of the hydraulic pressure expansion chamber provided on the other side in the axial direction. A thick-walled portion having a thick radial thickness and a thin-walled portion having a smaller radial thickness than the thick-walled portion in a range overlapping in the radial direction with the axial range to the end of the Therefore, it is easy to follow the hydraulic expansion surface where the sandwiching portion protrudes due to the hydraulic pressure of the annular hydraulic expansion chamber. Therefore, this makes it possible to increase the contact area between the hydraulic pressure expansion surface and the sandwiching portion, and to firmly fix the hydraulic pressure expansion surface and the sandwiching portion.

  In addition, the pressing of the clamping portion against the peripheral surface of the other member due to the overhang of the hydraulic expansion surface is not easily affected by the overhang of the adjacent hydraulic expansion surface, and the thick wall portion is pressed with the other force with a stronger force. It can be pressed against the peripheral surface of the member, and the frictional engagement between the cylindrical member and the shaft member becomes more reliable and strong.

In one embodiment,
The thin portion overlaps the position in the radial direction between the hydraulic expansion surfaces of the adjacent hydraulic expansion chambers.

  The thin portion that overlaps in the radial direction at a position between the adjacent hydraulic expansion chambers may overlap in the radial direction between the hydraulic expansion chambers in which the entire thin portion is adjacent, or the hydraulic pressure in which the thin portion is adjacent. It may overlap in the radial direction between the expansion chambers and at least one of the hydraulic expansion chamber on one side in the axial direction and the hydraulic expansion chamber on the other side in the axial direction.

  According to the embodiment, the thin wall portion is elastically deformed, so that the thick wall portion on one axial side of the thin wall portion can be easily along the hydraulic expansion surface of the hydraulic expansion chamber on one axial side. In addition, the thick part on the other axial side of the thin part can be easily along the hydraulic expansion surface of the hydraulic expansion chamber on the other axial side. By this, many parts of a thick part can be pressed on the surrounding surface of said other member, and the frictional engagement with a cylinder member and a shaft member becomes more reliable and firm.

The torque limiter of the present invention is
Comprising the shaft coupling device of the present invention,
By expanding the hydraulic expansion chamber in the radial direction of the one member with the liquid sealed in the hydraulic expansion chamber, the shaft member and the cylindrical member are frictionally engaged, while the hydraulic expansion chamber By removing the sealed liquid from the hydraulic expansion chamber, the frictional engagement between the shaft member and the cylindrical member is released.

  According to the present invention, since the shaft coupling device of the present invention is provided, the frictional engagement between the tubular member and the shaft member becomes more reliable and strong, and the hydraulic expansion surface of the hydraulic expansion chamber is It becomes hard to damage.

  According to the shaft coupling device of the present invention, the frictional engagement between the cylindrical member and the shaft member becomes more reliable and firm, and the hydraulic expansion surface of the hydraulic expansion chamber is less likely to be damaged.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a sectional view in the axial direction of a torque limiter which is an embodiment of the shaft coupling device of the present invention.

  The torque limiter includes a cylindrical member 1 as one member, a shaft member 2 as the other member, an annular member 3, a plurality of shear valves 6, a ball bearing 17, and a ball bearing 18.

  The cylindrical member 1 has a plurality of shear valve mounting holes 30 and a plurality of annular hydraulic expansion chambers 31. The hydraulic expansion chamber 31 constitutes a hydraulic expansion chamber. The plurality of shear valve mounting holes 30 are arranged at intervals in the axial direction. Each of the plurality of shear valve mounting holes 30 extends substantially in the radial direction. On the other hand, the plurality of hydraulic expansion chambers 31 are arranged at intervals in the axial direction. Each of the plurality of annular hydraulic expansion chambers 31 extends substantially in the axial direction. The inner peripheral surface of the cylindrical member 1 has a cylindrical inner peripheral surface 24. The cylindrical inner peripheral surface 24 extends in the axial direction from the vicinity of one end of the hydraulic expansion chamber 31 at one end to the vicinity of the other end of the hydraulic expansion chamber 31 at the other end. The surface overlapping the radially inward side of the hydraulic expansion chamber 31 is a hydraulic pressure expansion surface 32 that protrudes inward in the radial direction by the hydraulic pressure (hydraulic pressure) supplied to the hydraulic expansion chamber 31.

  The shaft member 2 has a main body portion 8 and a locking portion 9, and the main body portion 8 has a cylindrical outer peripheral surface 20 that forms a friction engagement surface. The locking portion 9 protrudes from the outer surface of the main body portion 8. The locking portion 9 has a substantially L-shaped cross section. The locking portion 9 has a radially extending portion 40 and an axially extending portion 41, and the radially extending portion 40 extends in the radial direction. A part of the radially extending portion 40 faces the axial end surface of the tubular member 1 in the axial direction. The axially extending portion 41 is connected to the radially outer end of the radially extending portion 40. The axially extending portion 41 extends in the axial direction along the outer peripheral surface of the cylindrical member 1.

  The annular member 3 is press-fitted and fixed to the cylindrical member 1. The annular member 3 includes an annular flange portion 42 and an annular sandwiching portion 43, and the sandwiching portion 43 is sandwiched between the cylindrical inner peripheral surface 24 of the tubular member 1 and the cylindrical outer peripheral surface 20 of the shaft member 2. Has been. The clamping part 43 has a cylindrical outer peripheral surface 25 and an inner peripheral surface 26, and the cylindrical outer peripheral surface 25 is in contact with the cylindrical inner peripheral surface 24 of the cylindrical member 1. On the other hand, the inner peripheral surface 26 of the clamping portion 43 has a cylindrical inner peripheral surface portion 54 and an annular concave portion 55, and the annular concave portion 55 is open to the cylindrical inner peripheral surface 54. Turbine oil or traction oil, which is lubricating oil for preventing seizure, is applied between the inner peripheral surface 26 of the clamping portion 43 and the cylindrical outer peripheral surface 20 of the shaft member 2. The cylindrical inner peripheral surface portion 54 of the clamping portion 43 is in contact with the cylindrical outer peripheral surface 20 of the shaft member 2.

  The annular recess 55 is located between the hydraulic expansion chambers 31 adjacent in the axial direction in the axial direction. The thickness in the radial direction of the portion 58 (hereinafter referred to as a thin portion) 58 that overlaps the concave portion 55 in the clamping portion 43 in the radial direction is the portion of the clamping portion 43 that overlaps the hydraulic expansion chamber 31 in the radial direction (hereinafter referred to as a thick portion). ) It is thinner than 59 radial thickness. The cylindrical inner peripheral surface portion 54 exists at a position substantially overlapping the thick portion 59 in the radial direction. The thin wall portion 58 overlaps in the radial direction at a position between the hydraulic expansion surfaces 32 of the hydraulic expansion chambers 31 adjacent in the axial direction in the axial direction.

  Each shear valve 6 is fitted into the shear valve mounting hole 30. In a state where the shear valve 6 is fitted in the shear valve mounting hole 30, one end of the shear valve 6 protrudes outward in the radial direction from the outer peripheral surface of the cylindrical member 1. The one end of each shear valve 6 is locked by an axially extending portion 41 of the locking portion 9 of the shaft member 2.

  The shear valve 6 has a tube 27 opened at only one end. The tube 27 extends substantially in the radial direction of the cylindrical member 1 in a state where the shear valve 6 is fitted in the shear valve mounting hole 30. In a state where the shear valve 6 is fitted in the shear valve mounting hole 30, one end portion on the closed side of the tube 27 protrudes outward in the radial direction from the outer peripheral surface of the cylindrical member 1. The side opposite to the closed side of the tube 27 communicates with the hydraulic expansion chamber 31 via an oil passage 28 formed in the cylindrical member 1. The hydraulic expansion chamber 31, the oil passage 28, and the tube 27 constitute a closed chamber.

  The ball bearing 17 includes an outer ring 70 fitted and fixed to the inner circumferential surface of the cylindrical member 1, an outer ring 71 fitted and fixed to the outer circumferential surface of the shaft member 2, a raceway surface of the outer ring 70, and a raceway of the inner ring 71. And a plurality of balls 72 arranged between the surfaces. The ball bearing 18 includes an outer ring 75 fitted and fixed to the inner circumferential surface of the annular member 3, an inner ring 76 fitted and fixed to the outer circumferential surface of the shaft member 2, a raceway surface of the outer ring 75, and an inner ring 76. A plurality of balls 77 arranged between the raceway surfaces. The ball bearings 17 and 18 are configured to rotatably support the annular member 3 with respect to the shaft member 2 when the annular member 3 rotates relative to the shaft member 2.

  In the above configuration, when a load of a predetermined value or less (load in a range where torque is transmitted) is applied to the cylindrical member 1 or the shaft member 2, the cylinder member 1 or the shaft member 2 is injected into the hydraulic expansion chamber 31 via a coupler (not shown). The hydraulic expansion surface 32 of the cylindrical inner peripheral surface 24 of the cylindrical member 1 is projected with the sealed oil for hydraulic expansion, and is pressed against the cylindrical outer peripheral surface 20 of the shaft member 2 via the clamping portion 43, thereby 1 and the shaft member 2 are frictionally coupled to transmit torque between the tubular member 1 and the shaft member 2.

  On the other hand, when the cylinder member 1 or the shaft member 2 is subjected to a load greater than a predetermined value (a load larger than the range in which torque is transmitted), the cylindrical inner peripheral surface 54 of the holding portion 43 of the annular member 3 is When the positions of the cylindrical member 1 and the shaft member 2 about the axis change due to slipping with respect to the cylindrical outer peripheral surface 20 of the main body 8, the locking portions 41 of the shaft member 2 are arranged in the radial direction of all the shear valves 6. The outer end of each of the hydraulic expansion chambers 31 is cut, and the oil for hydraulic expansion stored in all the hydraulic expansion chambers 31 is discharged to the outside through the tube 27 of the shear valve 6 whose one end is cut, The overhang of the hydraulic expansion surface 32 is eliminated. In this way, the pressing force of the cylindrical inner peripheral surface 54 of the annular member 3 against the cylindrical outer peripheral surface 20 of the shaft member 2 is eliminated, and the transmission of torque is interrupted by releasing the frictional coupling between the shaft member 2 and the annular member 3. It is supposed to be. In this way, when an overload occurs in the cylinder member 1 or the shaft member 2, the transmission of torque is interrupted to protect the expensive machine connected to the torque limiter device.

  According to the torque limiter of the above embodiment, the annular clamping portion 43 of the annular member is fixed to the cylindrical member 1, the cylindrical outer peripheral surface 20 of the shaft member 2, and the cylindrical inner peripheral surface of the cylindrical member 1. 24, the shaft member 2 does not come into contact with the hydraulic expansion chamber 32 that protrudes toward the shaft member 2 due to the hydraulic pressure of the annular hydraulic expansion chamber 31 formed in the cylindrical member 1. For this reason, the shaft member 2 makes it difficult for the hydraulic pressure expansion surface 32 to be twisted and to prevent friction, thereby preventing the hydraulic pressure expansion surface 32 from being damaged.

  And in the clamping part 43, the other end of the axial direction of the hydraulic expansion chamber 31 provided on the most other side in the axial direction from the end portion of the hydraulic direction of the hydraulic expansion chamber 31 provided on the most one side in the axial direction. A thick portion 59 having a large thickness in the radial direction and a thin portion 58 having a smaller thickness in the radial direction than the thick portion 59 in a range overlapping in the radial direction with the axial range to the end on the side. Therefore, it is easy to follow the hydraulic expansion surface 32 where the clamping portion 43 protrudes due to the hydraulic pressure of the annular hydraulic expansion chamber 31. Therefore, this makes it possible to increase the contact area between the hydraulic pressure expansion surface 32 and the sandwiching portion 43, and to firmly fix the hydraulic pressure expansion surface 32 and the sandwiching portion 43.

  Further, the pressing of the clamping member 43 to the cylindrical outer peripheral surface 20 of the clamping portion 43 due to the overhang of the hydraulic expansion surface 32 is not easily affected by the overhang of the adjacent hydraulic expansion surface 32, and the thick portion 59 is It can be pressed against the cylindrical outer peripheral surface 20 of the shaft member 2 with a stronger force, and the frictional engagement between the tubular member 1 and the shaft member 2 becomes more reliable and strong.

  Further, according to the torque limiter of the above-described embodiment, the thin portion 58 is elastically deformed, so that the thick portion 59 on one axial side of the thin portion 58 is in the hydraulic expansion chamber 31 on one axial side. In addition to being easy to follow along the hydraulic expansion surface 32, the thick portion 59 on the other axial side of the thin portion 58 can be easily along the hydraulic expansion surface 32 of the hydraulic expansion chamber 31 on the other axial side. As a result, many portions of the thick portion 59 can be pressed against the cylindrical outer peripheral surface 20 of the shaft member 2, and the frictional engagement between the tubular member 1 and the shaft member 2 is further ensured and strong. Become a thing.

  In the torque limiter of the above embodiment, the annular hydraulic expansion chambers 31 are arranged in three rows in the axial direction. However, in the present invention, the annular hydraulic expansion chambers are arranged in two rows or four or more rows in the axial direction. You may arrange in.

  In the torque limiter of the above embodiment, the hydraulic expansion chamber is the hydraulic expansion chamber 31 and the liquid filled in the hydraulic expansion chamber is oil. However, in the present invention, the hydraulic expansion chamber is filled. The liquid may be any liquid other than oil.

  In the torque limiter of the above embodiment, the thin wall portion 58 exists between the two hydraulic expansion chambers 31 adjacent to each other in the axial direction. However, in the present invention, the thin wall portion is in the axial direction in the axial direction. It may be located outside in the axial direction of at least one of the hydraulic expansion chambers at one end and the other end.

  In the torque limiter of the above embodiment, the plurality of annular hydraulic expansion chambers are formed in the cylindrical member 1, but in the present invention, a plurality of hydraulic expansion chambers may be formed in the shaft member. In this case, for example, the shear valve mounting hole may be formed in the shaft member so as to extend in the axial direction and to open to the end surface in the axial direction of the shaft member.

  Further, in the torque limiter of the above embodiment, the thin wall portion 58 overlaps the position between the hydraulic expansion surfaces 32 of the hydraulic expansion chambers 31 adjacent in the axial direction in the radial direction. It is not necessary to overlap the position between the hydraulic expansion surfaces of the hydraulic expansion chambers in the radial direction, and the thin wall portion is positioned between the hydraulic expansion surfaces of the adjacent hydraulic expansion chambers and adjacent hydraulic expansion chambers It may extend to a position overlapping one or both of the hydraulic pressure expansion surfaces in the radial direction.

  In the torque limiter of the above embodiment, the thin portion 58 is formed in a circular arc shape in the cross section. However, in the present invention, the thin wall portion may have a rectangular cross section or a triangular cross section. However, it is preferable to form the cross section in an arc shape because stress concentration due to deformation of the sandwiching portion 43 hardly occurs.

  In the torque limiter of the above embodiment, the thin portion 58 is formed so as to be recessed from the inner peripheral surface 26 of the annular holding portion 43. However, in this invention, the thin portion is formed from the cylindrical outer peripheral surface of the annular holding portion. You may form so that it may become depressed, or you may form so that it may be depressed from both the cylindrical outer peripheral surface and inner peripheral surface of a cyclic | annular clamping part. When forming so as to be recessed from both the cylindrical outer peripheral surface and the inner peripheral surface of the annular sandwiching portion, the position where the cylindrical outer peripheral surface is recessed and the position where the inner peripheral surface is recessed may coincide or be separated good.

  In the above embodiment, the shaft coupling device is a torque limiter. However, the shaft coupling device of the present invention is not limited to the torque limiter. For example, the shaft coupling device of the present invention is a shaft that does not have a structure for discharging the liquid in the hydraulic expansion chamber to the outside, as described in JP-A-5-296252 and JP-A-6-18733. A coupling device may be used.

It is sectional drawing of the axial direction of the torque limiter which is one Embodiment of the shaft coupling device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tube member 2 Shaft member 3 Ring member 6 Shear valve 20 Cylindrical outer peripheral surface of a shaft member 24 Cylindrical inner peripheral surface of a cylindrical member 31 Hydraulic expansion chamber 58 Thin part 59 Thick part

Claims (3)

A shaft member having an outer peripheral surface;
A cylindrical member having an inner circumferential surface opposed to the outer circumferential surface in the radial direction;
An annular member having an annular clamping portion sandwiched between the outer peripheral surface of the shaft member and the inner peripheral surface of the cylindrical member;
One of the shaft member and the cylindrical member is disposed at an axial interval from each other, and the peripheral surface of the one member is disposed between the shaft member and the cylindrical member via the clamping portion. A plurality of annular hydraulic expansion chambers having an annular hydraulic expansion surface that presses against the peripheral surface of the other member of
The clamping portion is fixed to the one member,
The clamping unit is configured so that the end of the hydraulic expansion chamber provided on the other side in the axial direction extends from the end on the one side in the axial direction of the hydraulic expansion surface of the hydraulic expansion chamber provided on the most one side in the axial direction. A thick portion with a thick radial thickness and a thicker radial portion than the thick portion in a range that overlaps the radial range to the axial range to the other end in the axial direction of the hydraulic expansion surface And a thin thin-walled portion. The shaft coupling device according to claim 1,
The thin-walled portion overlaps the radial direction at a position between the hydraulic expansion surfaces of the adjacent hydraulic expansion chambers. A shaft coupling device according to claim 1 or 2,
By expanding the hydraulic expansion chamber in the radial direction of the one member with the liquid sealed in the hydraulic expansion chamber, the shaft member and the cylindrical member are frictionally engaged, while the hydraulic expansion chamber A torque limiter that releases the frictional engagement between the shaft member and the tubular member by removing the sealed liquid from the hydraulic expansion chamber.

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