JP2844516B2 - Sliding detection mechanism of hydraulic torque limiting shaft coupling - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving-side member generated by overload or the like in a hydraulic torque limiting shaft coupling that operates by the pressure of liquid and connects a driving-side rotation shaft and a driven-side rotation shaft. The present invention relates to a slip detection mechanism of a hydraulic torque limiting shaft coupling for detecting slip between a member and a driven member.

[0002]

2. Description of the Related Art As a conventional hydraulic torque limiting shaft coupling and its slip detecting mechanism, for example, there is one disclosed in Japanese Patent Publication No. 6-23680.

FIG. 4 is a block diagram showing an example of a conventional hydraulic torque limiting shaft coupling and an example of a slip detecting mechanism thereof, and FIG. 5 is an operation explanatory diagram of the hydraulic torque limiting shaft coupling shown in FIG. 1
Is a fitting body, 2 is a fitting hole opened at one end face of the fitting body 1, 3 is a hydraulic chamber formed in the fitting body 1 along the inner peripheral surface of the fitting hole 2, 4 is a fitting body 1 The flange fixed to the other end surface of the other, and 51 and 52 are each a rotating shaft, one is connected to a reducer or the like and configured as a drive shaft, and the other is connected to a rolling roll or the like and configured as a driven shaft. I have. A flange 53 is fixed to an end of the rotating shaft 51 by welding or the like, and a shear lug 5 as a shearing member is fixed to an outer peripheral surface of the rotating shaft 52. A portion of the rotating shaft 52 closer to the tip end than the shear lug 5 is formed as a fitting insertion portion 52a whose diameter is slightly smaller than the inner diameter of the fitting hole 2.

[0004] The joint body 1 is formed with a screw hole that opens on the outer peripheral surface of the joint body 1, and a communication hole 6 that communicates with the hydraulic chamber 3 is opened at the bottom of the screw hole. A shear tube 7 is screwed into the screw hole, and the shear tube 7 has an outlet hole 7b which is opened at the front end and sealed at the rear end by a lid 7a. Connected to the communication hole 6. Further, the lid 7a protrudes from the outer peripheral surface of the joint body 1 and is formed in a shape that is easily sheared by a shearing force in a direction along the outer peripheral surface.

[0005] By fixing the flange 53 of the rotating shaft 51 to the flange 4 of the joint body 1 with bolts or the like, the rotating shaft 51 and the joint body 1 are coaxially fixed. Further, the rotary shaft 52 inserts the insertion portion 52a into the insertion hole 2, and holds the shear lug 5 at a position slightly separated from the end surface and the outer peripheral surface of the joint body 1 in this state. A U-shaped notch 5a is formed in the shear lug 5, and the initial position of the rotating shaft 52 is adjusted such that the lid 7a of the shear tube 7 becomes the center of the notch 5a in the rotation direction.

As shown in FIG. 5, the joint body 1 is formed with a lubrication port 8 which opens on the outer peripheral surface, and a lubrication hole 9 which opens at the bottom of the lubrication port 8 and the hydraulic chamber 3. A lubrication nipple 10 is screwed into the lubrication port 8. The lubricating nipple 10 has a hemispherical tip portion, a gap formed between the lubricating nipple 10 and the lubrication port 8, and an lubrication hole 10a opening at the rear end.
It has. By tightening the lubricating nipple 10, the tip of the lubricating nipple 10 presses against the opening of the lubricating hole 9 in the lubricating hole 8 to seal the lubricating hole 9, and by loosening the lubricating nipple 10, the lubricating hole The oil hole 10a and the oil hole 9 communicate with each other through a gap between the oil hole 10a and the oil hole 10.

A hydraulic hose 55 is connected to the lubricating nipple 10,
When high-pressure hydraulic oil is filled into the hydraulic chamber 3 by a hydraulic unit (not shown), the fitting portion 52 of the rotary shaft 52 is inserted into the fitting hole 2.
If a is not inserted, the partition wall 11 formed between the inner peripheral surface of the fitting hole 2 and the hydraulic chamber 3 bulges in the radial direction as shown by a two-dot chain line, and lubrication is performed in this state. nipple
By tightening 10, high-pressure hydraulic oil is sealed in the hydraulic chamber 3.

[0008] As shown in FIG.
By filling high-pressure hydraulic oil in the hydraulic chamber 3 with the fitting portion 52a of the fitting hole 52a fitted, the inner peripheral surface of the fitting hole 2 is
The frictional force corresponding to the pressure of the hydraulic oil is generated by being pressed against the outer peripheral surface of a, and the rotating shaft 51 and the rotating shaft 52 are connected by the frictional force, so that torque can be transmitted.

Here, the rotation shaft 51,
When the torque transmitted between the two shafts 52 becomes larger than the allowable torque, the joint body 1 causes the inner circumferential surface of the fitting hole 2 to rotate against the frictional force acting on the outer circumferential surface of the fitting portion 52a. By sliding on the outer peripheral surface, the phase with respect to the rotating shaft 52 is displaced.

When the phase of the joint body 1 with respect to the rotary shaft 52 is displaced from the initial position, the notch 5a of the shear lug 5 shears the lid 7a of the shear tube 7, thereby opening the rear end of the outflow hole 7b. The high-pressure hydraulic oil in the hydraulic chamber 3 flows out of the outflow hole 7b. When the high-pressure hydraulic oil flows out of the hydraulic chamber 3, the frictional force generated by the oil pressure between the inner peripheral surface of the fitting hole 2 and the outer peripheral surface of the fitting portion 52a disappears. On the other hand, the joint main body 1 runs idle and no torque transmission is performed. As described above, when an excessive torque greater than the allowable torque set by the pressure of the hydraulic oil is generated, the joint body 1 is idled to interrupt the torque transmission, so that the rotating shafts 51 and 52 and a drive not shown are omitted. The mechanism and the like can be prevented from being damaged by overload.

The proximity switch 21 facing the outer peripheral surface of the joint body 1 is supported by a member (not shown) so as to be located at the same position as the shear tube 7 in the axial direction. Here, as the proximity switch 21, for example, a high-frequency transmission type proximity switch is used, and the distance from the shear tube 7 is set so that the proximity switch 21 is turned on when the lid 7a is at the opposing position.

An ON signal from the proximity switch 21 when the rotation shafts 51 and 52 rotate is output to the slip occurrence detection circuit 22 at a cycle corresponding to the rotation speed of the rotation shafts 51 and 52. The slip occurrence detection circuit 22 starts counting time by an internal timer (not shown) at the timing when the ON signal from the proximity switch 21 is input, resets the counting time of the internal timer by inputting the next ON signal, and starts counting again. As described above, when the lid 7a is cut off from the shear tube 7 by the shear lug 5, the proximity switch 21 is not turned on by the lid 7a, so that an ON signal is not output. At this time, the slip occurrence detection circuit 22 detects the slip occurrence when the ON signal from the proximity switch 21 is not input for the slip occurrence detection time set according to the rotation speed of the rotating shafts 51 and 52 from the previous input. Output a signal. The slip occurrence detection signal is output to, for example, a motor control circuit of the driving mechanism, whereby the motor control circuit causes the driving mechanism to stop in an emergency.

[0013]

However, in the above-mentioned hydraulic torque limiting shaft coupling, the shear tube 7
Since the high pressure hydraulic oil is sealed, when the lid 7a is sheared by the shear lug 5, which is a shearing member when excessive torque is generated, the lid 7a pops out at high speed in the radial direction due to the pressure of the hydraulic oil. For this reason, when the proximity switch 21 is located at the opposite position, the lid 7a
The proximity switch 21 is destroyed by colliding with it, and the splash of hydraulic oil flowing out of the shear tube 7 adheres to the proximity switch 21 and causes malfunction and failure of the proximity switch 21.

4 and 5, for the sake of simplicity, only one shear tube 7 is shown in the joint main body 1, but a plurality of shear tubes 7 are provided in the joint main body 1. When excessive torque is generated, each lid 7
By simultaneously shearing a with the shear lag 5,
The response time from the occurrence of slip to the start of idling of the joint body 1 can be shortened, and the slip occurrence detection time for judging slip of the joint body 1 can be shortened. However, as the number of shear tubes 7 increases, the lid 7a
There is a problem that the possibility of destroying 1 is increased.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems by preventing a sensor such as a proximity switch from being destroyed and detecting a slippage of a joint body in a short period of time. Is to provide.

[0016]

In order to solve the above-mentioned problems, a first means of the present invention comprises a column-shaped insertion portion provided at an end of a first rotating shaft, and a second rotating shaft. A joint body formed coaxially with the shaft and having a fitting hole with a circular cross section opened at at least one end surface; an annular hydraulic chamber formed inside the fitting body along the fitting hole; When the pressure chamber is filled with high-pressure hydraulic fluid, a fitting hole inner peripheral surface that swells in the radial direction and presses the fitting hole inner peripheral surface against the fitting insertion portion outer peripheral surface that fits into the fitting hole. A partition wall formed between the hydraulic chamber and a shear tube fixed to a communication hole communicating with the hydraulic chamber and projecting a lid portion sealing the communication hole from an outer peripheral surface of the joint body. When the joint body is fixed with respect to the first rotation axis and the joint body is displaced in the rotation direction with respect to the insertion portion, the lid is sheared. Hydraulic torque limit shaft for detecting the displacement in the rotational direction of the joint body relative to the fitting portion in the hydraulic torque limiting joint comprising a shear member to flow out the high pressure hydraulic fluid to the outside of the liquid in the pressure chamber and A slip detection mechanism for a joint, wherein the shear member is fixed to the joint body at a position different from the shear tube in the axial direction, and when the joint body is displaced in the rotational direction with respect to the insertion portion, the outer periphery of the joint body by the shearing member. It is characterized by comprising a striker in which a detected part protruding from a surface is sheared, and a sensor arranged to face the outer peripheral surface of the joint body and detecting the detected part passing through a facing position.

Further, the second means is characterized in that a plurality of the strikers are arranged on the same line in the circumferential direction.

Further, the third means is characterized in that a plurality of the sensors are arranged on the same line in the circumferential direction.

[0019]

According to the first means, when transmitting a torque equal to or less than the permissible torque, the sensor detects the detected portion at a cycle corresponding to the rotation speed of the rotating shaft, and the joint body is moved relative to the fitting portion due to overload or the like. When the is displaced in the rotation direction, the detected portion of the striker and the lid of the shear tube are sheared, so that the joint body idles with respect to the fitting portion, the sensor does not detect the detected portion, and the hydraulic pressure is reduced. High-pressure hydraulic fluid flows out of the chamber.

Further, according to the second means, the time from when the sensor detects the detected portion of the striker when the joint body is rotated to when the next detected portion is detected is shortened.

Further, according to the third means, the time from when the detected portion is detected by the sensor during rotation of the joint body to when the detected portion is next detected is reduced.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. In FIGS. 1 and 2, members corresponding to those described with reference to FIGS. 4 and 5 are denoted by the same reference numerals and description thereof is omitted. FIG. 1 is a configuration diagram showing a hydraulic torque limiting shaft coupling to which an embodiment of a slip detecting mechanism of the present invention is applied, and FIG. 2 is a diagram showing a hydraulic torque limiting shaft coupling of the present embodiment and a main part of the slip detecting mechanism. It is sectional drawing. Reference numeral 31 denotes a cylindrical sleeve, and the sleeve 31 as a fitting portion is fixed to an end of the outer peripheral surface of the rotating shaft 52 by a key 32.
Reference numeral 33 denotes a shear lug, which is a shearing member fixed to an end surface of the sleeve 31 with bolts or the like, and reference numeral 34 denotes a pair of rotary bearings disposed near both ends of the outer peripheral surface of the sleeve 31.

Reference numeral 35 denotes a flange hub having a fitting hole 35a having a circular cross section opened at one end surface and a flange portion 35b formed at the other end. The flange hub 35 has a flange portion 35b and a flange 53 formed of bolts or the like. And is coaxially fixed to the rotating shaft 51. Reference numeral 36 denotes a ring-shaped hydraulic fixing member that is fitted to the flange hub 35, and is a hydraulic fixing member.
In the inside 36, an annular hydraulic chamber 37 is formed along the inner peripheral surface. The inner peripheral surface of the flange hub 35 and the vicinity of one end of the inner peripheral surface of the hydraulic fixing member 36 are pressed against the outer peripheral surface of the rotary bearing 34, respectively. Here, the flange hub 35 and the hydraulic fixing member 36 are fixed coaxially with the rotating shaft 51 to form a joint body.

Lubricating nipple disposed on hydraulic fixing member 36
(Not shown) to fill the hydraulic chamber 37 with high-pressure hydraulic oil,
By sealing the high-pressure hydraulic oil in the hydraulic chamber 37 by tightening the oil nipple, the inner peripheral surface of the hydraulic
A partition wall 38 between the bulges 37 and 37 bulges in the radial direction. As a result, the hydraulic fixing member 36 applies uniform compressive stress to the outer peripheral surface of the flange hub 35, and contracts the flange hub 35 in the radial direction. When the flange hub 35 contracts in the radial direction, a fitting hole 35a of the flange hub 35 is formed.
A frictional force corresponding to the pressure of the hydraulic oil acts on the outer peripheral surface of the sleeve 31 inserted into the
35 and the sleeve 31 are fixed. As a result, the rotating shaft 51 and the rotating shaft 52 are connected, and torque transmission becomes possible within the allowable torque range set by the pressure of the hydraulic oil.

A striker 41 is screwed onto the outer peripheral surface of the hydraulic fixing member 36 at a position different from the shear tube 7 in the axial direction (the direction of the arrow A). 41a is projected. The proximity switch 21 facing the outer peripheral surface of the hydraulic fixing member 36 is supported by a member (not shown) so as to be at the same position as the striker 41 in the axial direction. Here, as the proximity switch 21 as a sensor, for example, a high-frequency transmission type proximity switch is used, and the distance from the striker 41 is set so that the proximity switch 21 is turned on when the detection target 41a is at the opposing position.

An ON signal from the proximity switch 21 when the rotating shafts 51 and 52 are rotating is output to the slip occurrence detecting circuit 22 at a cycle corresponding to the rotating speed of the rotating shafts 51 and 52. The slip occurrence detection circuit 22 starts counting time by an internal timer (not shown) at the timing when the ON signal from the proximity switch 21 is input, resets the counting time of the internal timer by inputting the next ON signal, and starts counting again.

Here, the rotation shaft 51,
If the torque transmitted between 52 becomes larger than the allowable torque, the inner peripheral surface of the fitting hole 35a is
By sliding on the outer peripheral surface, the phases of the flange hub 35 and the hydraulic fixing member 36 with respect to the sleeve 31 are displaced. When the phase of the hydraulic fixing member 36 with respect to the sleeve 31 is displaced from the initial position, the notch 33a of the shear lug 33 shears the lid 7a of the shear tube 7 and the detected portion 41a of the striker 41.

When the lid 7a is sheared, the high-pressure hydraulic oil in the hydraulic chamber 37 flows out through the shear tube 7 and the hydraulic pressure between the inner peripheral surface of the fitting hole 35a and the outer peripheral surface of the sleeve 31 is increased. The frictional force that has been caused by the elimination is eliminated. At this time, the flange hub 35 and the hydraulic fixing member 36 idle with respect to the sleeve 31 via the rotary bearing 34, and the rotating shaft 5
No torque transmission is performed between 1 and 52. At this time, since the shear tube 7 is arranged at a position different from the striker 41 in the axial direction, the shear tube 7
The operating oil flowing out of the switch is prevented from adhering to the proximity switch 21.

Further, the striker 41 is provided by the shear lag 33.
The detected part 41a is sheared, thereby causing the proximity switch 2
1 is not turned on by the detected part 41a and does not output an on signal. At this time, the slip occurrence detection circuit 22 operates the proximity switch 21 for the slip occurrence detection time from the previous input.
If no ON signal is input, a slip occurrence detection signal is output. The slip occurrence detection signal is output to, for example, a motor control circuit of the driving mechanism, whereby the motor control circuit causes the driving mechanism to stop in an emergency.

The striker 41 is formed of an easily shearable material such as SS41. Also striker
When the sheared portion 41a is sheared by the shear lug 33, only the centrifugal force and the inertial force in the tangential direction on the outer peripheral surface of the hydraulic fixing member 36 act on the detected portion 41a of the detected portion 41a. Unlike the portion 7a, it does not jump out at high speed in the radial direction. For this reason, the sheared detected portion 41a
Even if the vehicle collides with the proximity switch 21, the impact force at the time of the collision is suppressed and the proximity switch 21 can be prevented from being broken.

Further, since the striker 41 can be formed of a material having a low specific gravity, such as aluminum or plastic, the safety at the time of collision can be further improved by using such a material.

FIGS. 3A and 3B are explanatory views showing examples of the arrangement of the striker and the proximity switch in the slip detection mechanism of this embodiment.

In the hydraulic fixing member 36 shown in FIG. 3A, two strikers 41 are arranged at an interval of 180 ° in the circumferential direction, and the two strikers 41 are rotated by one proximity switch 21 during rotation. The detected portions 41a are alternately detected. By arranging the two strikers 41 on the hydraulic fixing member 36, the detected portion 41a is detected by the proximity switch 21 in a half rotation cycle during normal torque transmission, so that the rotation speed of the rotation shafts 51 and 52 is reduced. The slip occurrence detection time set correspondingly can be shortened, and the time from the occurrence of the slip when the detected portion 41a is sheared by the shear lug 33 to the output of the slip occurrence detection signal can be shortened. Of course, it is also possible to provide three or more strikers 41 on the hydraulic fixing member 36, and with the increase in the number of strikers 41, the time from the occurrence of slip to the output of the slip detection signal can be further reduced.

The two proximity switches 21 are opposed to the hydraulic fixing member 36 shown in FIG.
Detect the detected part 41a alternately. By arranging two proximity switches 21 so as to face the hydraulic fixing member 36,
Proximity switch with 1/2 rotation cycle during normal torque transmission
21 alternately detects the detection target 41a.
It is possible to reduce the slip occurrence detection time set in accordance with the rotation speed of the rotation speed, and shorten the time from the occurrence of the slip when the detected part 41a is sheared by the shear lug 33 to the output of the slip occurrence detection signal. Of course, the hydraulic fixing member 36
It is also possible to dispose three or more proximity switches 21 so as to face each other. With the increase of the proximity switches 21, the time from the occurrence of slip to the output of a slip occurrence detection signal can be further reduced.

[0035]

As described above, according to the first aspect of the present invention, when torque is transmitted below the allowable torque, the sensor detects the portion to be detected at a cycle corresponding to the rotation speed of the rotating shaft, and the overload is detected. When the joint body is displaced in the rotation direction with respect to the fitting portion due to, for example, the detected portion of the striker and the lid portion of the shear tube are sheared, the sensor does not detect the detected portion, and the high pressure from the hydraulic chamber is high. When the hydraulic fluid flows out, it is possible to detect slippage of the joint body with respect to the insertion portion of the rotary shaft in accordance with the detection signal from the sensor and the rotation speed of the rotary shaft . If the lid of the detection part and the shear tube striker is sheared, the the detected portion of the striker for only the inertial force of the outer peripheral surface tangent direction of the centrifugal force and the fitting body acts, sheared Even if the sensing part collides with the sensor, the impact force at the time of the collision is suppressed and the sensor can be prevented from being destroyed, and high-pressure hydraulic fluid flows out of the hydraulic chamber of the joint body. occur were fitting portion and the fitting body by frictional force disappears between the joint body is enabled idle.

Further, according to the second means, the time from when the sensor detects the detected part of the striker to the next detection of the detected part during the rotation of the joint body is shortened, so that With the increase, the time for detecting that the detected portion has been sheared by the shearing member can be reduced, and the time until slippage of the joint body with respect to the insertion portion of the rotating shaft can be reduced.

Further, according to the third means, the time from when the detected part is detected by the sensor to the next detection when the joint body is rotated is shortened. by reducing the time for detecting that the detected portion is sheared, fitted the rotary shaft
The time until the slip of the joint body with respect to the part is detected can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a hydraulic torque limiting shaft coupling to which an embodiment of a slip detection mechanism of the present invention is applied.

FIG. 2 is a sectional view of a main part of a hydraulic torque limiting shaft coupling and a slip detection mechanism of the embodiment.

FIG. 3 is an explanatory diagram showing an example of arrangement of a striker and a proximity switch in the slip detection mechanism according to the embodiment.

FIG. 4 is a configuration diagram showing an example of a conventional hydraulic torque limiting shaft coupling and a slip detection mechanism thereof.

FIG. 5 is an operation explanatory view of the hydraulic torque limiting shaft coupling shown in FIG. 4;

[Explanation of symbols]

7: Shear tube, 7a: Lid, 21: Proximity switch, 22: Sliding occurrence detection circuit, 33: Sharlag,
35: flange hub, 35a: fitting hole, 36: hydraulic fixing member, 37: hydraulic chamber, 41: striker, 41a: detected part, 51, 52: rotating shaft.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Fumio Nishimura, Investigator, Kashima-cho, Kashima-gun, Ibaraki 3rd floor, Kashima Works, Sumitomo Metal Industries, Ltd. No. Kawasaki Heavy Industries, Ltd. Kobe Factory (72) Inventor Akihiko Morita 3-1-1 Higashi Kawasaki-cho, Chuo-ku, Kobe Kawasaki Heavy Industries, Ltd. Kobe Factory (72) Inventor Michihiro Ito 3--10 Tsukiji, Chuo-ku, Tokyo No. 10 Nakamura Motor Co., Ltd. (72) Inventor Ikuo Takahashi 3-10-10 Tsukiji, Chuo-ku, Tokyo Co., Ltd. Nakamura Motor Co., Ltd. (56) References JP-A-5-340844 (JP, A) Kaihei 4-121538 (JP, U) Shokai 5-38426 (JP, U) Shokai 61-131664 (JP, U) Shokai 62-46836 (JP, U) (58) Int .Cl. ⁶ , DB name) F16D 7/02 F16D 9/00 F16D 43/286

Claims (3)

(57) [Claims] 1. A columnar fitting portion (31) provided at an end of a first rotating shaft (52) and fixed coaxially with a second rotating shaft (51) and open at least at one end surface. Joint body (35, 36) in which fitting hole (35a) with circular cross section is formed
An annular hydraulic chamber (37) formed inside the joint main body along the fitting hole, and when the hydraulic chamber is filled with a high-pressure hydraulic fluid, the hydraulic chamber bulges in the radial direction to form the fitting. Crimping the inner peripheral surface of the fitting hole to the outer peripheral surface of the fitting portion to be inserted into the mating hole ,
A partition (3) formed between the inner peripheral surface of the fitting hole and the hydraulic chamber.
8) a shear tube secured to a communication hole (6) communicating with the hydraulic chamber, and a lid (7a) for sealing the communication hole protruding from the outer peripheral surface of the joint body. (7) and the first
Is fixed with respect to the rotation axis, said fitting if the fitting body is displaced in the rotational direction with respect to insertion portion, the shear member to flow out the high-pressure working fluid of the lid portion and the liquid pressure chamber shears the outside (33 ) With a hydraulic torque limiting shaft coupling
A slippage detection mechanism of a hydraulic torque limiting shaft coupling for detecting displacement of the joint body in the rotation direction with respect to the insertion portion , wherein the slippage detection mechanism is fixed to the joint body at a position different from the shear tube in an axial direction, When the joint main body is displaced in the rotation direction with respect to the fitting portion, the detected member (41a) projecting from the outer peripheral surface of the joint main body is sheared by the shearing member, and the striker (41) is opposed to the outer peripheral surface of the joint main body. And a sensor (21) for detecting the detected portion passing through the opposed position. 2. A scan Toraika (41) to the circumferential direction, characterized in that a plurality arranged on the same line according to claim 1, wherein the hydraulic torque limiting joint of slip detection mechanism. 3. A sensor (21), characterized in that a plurality arranged on the same line in the circumferential direction according to claim 1, wherein the hydraulic torque limiting joint of slip detection mechanism.