JP2002048662A - Socket of torque-measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a socket which enables highly accurately measuring a torque by uniformly dispersing a stress strain applied to a leaf spring. SOLUTION: The torque-measuring device comprises a hollow cylindrical socket body 34 rotatable to a easing 41, a socket part 32 set to an upper end of the socket body to be engaged with a torque transmission part of a clamping tool, and a torque-receiving part 36 set to a lower end of the socket body to be coupled to the other end of the leaf spring 40 having one end supported to part of the casing and, measures the stress strain generated by the torque to the leaf spring by a strain gauge 42. The socket of the device is constituted of a pair of expanding slots 35 and 35 recessed in a lower end opening of the socket body to intersect an axial center of the cylinder to allow the leaf spring to be inserted, and expanded base end parts 39 and 39 having a larger diameter than a breadth of the expanding slot and set to a deep base end of the pair of expanding slots. The leaf spring and the socket body held between the expanding slots are clamped and fixed in common by a clamping unit 37.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque measuring device for detecting a tightening torque value and setting an appropriate torque value in various tightening tools such as an electric screwdriver and a wrench, and more particularly to a tightening tool. The present invention relates to an improvement in a socket for a torque measuring instrument capable of transmitting a torque value obtained by the method properly and accurately.

[0002]

2. Description of the Related Art When setting and detecting the tightening torque values of various tightening tools, the present applicant measures steplessly and with high accuracy with a single torque detector over a wide range of torque. A torque detector configured to obtain the torque was developed, and was successfully commercialized (Japanese Patent Laid-Open No. 55-246).
No. 51).

That is, the configuration of a main torque measuring mechanism of a torque detector that has already been put into practical use is as shown in FIG. In FIG. 3, a main torque measuring mechanism unit 10 of the torque detector is a torque transmitting unit (rotary shaft unit) of a tightening tool.
And a socket body 1 integrally coupled to the socket portion 12 and arranged coaxially with the torque transmitting portion of the tightening tool to receive torque transmission.
4 is provided. That is, the torque receiving portion 16 is connected to the casing 20 via the bearing 18.
The socket portion 12 is rotatably supported, and is configured and arranged such that the socket portion 12 is exposed to the outside of the casing 20.

On the other hand, the socket body 14 of the torque receiving portion 16 is located inside the casing 20 and
One end is configured and arranged to lock the other end of a leaf spring 24 supported at a fulcrum by a support member 22 fixed inside the casing 20. A strain gauge 26 is attached to a part of the leaf spring 24 close to the socket body 14 side.

[0005] In the torque detector thus configured, a torque transmitting portion of a tightening tool such as an electric screwdriver is engaged with the socket portion 12 of the torque receiving portion 16 and torque is output by rotating the tool. As a result, torque is transmitted to the socket body 14 in the torque receiving portion 16 and the socket body 14 receives torque for rotating the socket body 14 in a predetermined direction. The torque associated with the rotation of the socket body 14 causes a required stress distortion at the other end of the leaf spring 24. Therefore, the magnitude of the stress distortion generated in the leaf spring 24 can be appropriately measured as a torque value in the torque transmitting portion of the tightening tool by the strain gauge 26.

However, in the torque detector having the above-described structure, in order to measure the torque value in the torque transmitting portion of the tightening tool with high accuracy, the torque receiving portion 16 of the main torque measuring mechanism 10 and the leaf spring 24 are required. The coupling configuration is important. That is, it is necessary to smoothly transmit the stress from the torque receiving portion 16 to the leaf spring 24.

[0007] From such a viewpoint, in the conventional main torque measuring mechanism 10, for example, (a) and (b) of FIG.
The configuration shown in FIG. That is, the torque receiving portion 1
A pair of split grooves 25, 25 having a fixed width (substantially the same as the plate thickness of the plate spring 24) are formed in the socket body 14 of No. 6 and having a fixed width (substantially the same as the plate thickness of the plate spring 24) which crosses the cylindrical axis and has an open lower end. One end 24a of the leaf spring 24 is inserted above the split grooves 25, 25 into the split grooves 25, 25 of the socket body 14 of the torque receiving portion 16 formed as described above, and the lower side of the split grooves 25, 25 is inserted. At this point, a fastener such as a bolt 27a and a nut 27b is fastened so as to intersect with the split grooves 25, 25, and the one end 24a of the leaf spring 24 is locked so as not to fall down.

Therefore, according to the main torque measuring mechanism 10 having the above-described configuration, the one end 24a of the leaf spring 24 that causes the stress distortion according to the torque value transmitted while being locked to the torque receiving portion 16 is connected. It has been considered that stress transmission can be realized properly and with high accuracy by simply holding the device without directly fixing it with a fastener.

However, in the coupling structure of the torque receiving portion 16 and one end 24a of the leaf spring 24, for example, the torque receiving portion 16 receives a required torque from the outside and receives the required torque from the outside through the socket body 14. When stress distortion occurs in one end 24a of the
If the abutting state between the respective portions of the leaf springs 24, i.e., one portion y1, y2 and the other portions y3, y4, is not uniform, the dispersion of the stress strain applied to the leaf spring 24 will be described. Are imbalanced, and it becomes difficult to measure with high accuracy using the strain gauge 26 (see FIGS. 4A and 4B).

In the main torque measuring mechanism 10 having the above-described configuration, the portions y1, y2 of the leaf spring 24 with respect to the split grooves 25, 25 of the socket body 14 are provided.
It is necessary that the contact state between y2 and y3, y4 is always equal. However, in the configuration shown in FIGS. 4A and 4B, it is difficult to realize the configuration.

[0011]

The inventor of the present invention has conducted research and trial production to overcome the above-mentioned drawbacks. As a result, the present inventors have provided a socket portion which engages with a torque transmitting portion of various tightening tools and the like. A rotatable torque receiving portion, and a leaf spring that supports one end at a part of the casing and supports the other end with the torque receiving portion to generate stress distortion, are provided at predetermined positions of the leaf spring. In configuring a torque measuring device to which a strain gauge is attached, a socket body integrally formed with a socket portion of the torque receiving portion,
A pair of split grooves having substantially the same size as the leaf spring are provided, crossing the cylindrical axis and opening at the lower end. The other end of the leaf spring is fitted and clamped in the split groove, The plate spring can be evenly brought into contact with the split groove of the socket body of the torque receiving portion by tightening and fixing with a tightening tool so as to penetrate the center portion, and furthermore, dispersion of stress strain applied to the plate spring. It was also found that the torque could be balanced and extremely accurate torque measurement could be performed.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to perform high-precision torque measurement by uniformly dispersing stress strain applied to a leaf spring from a torque receiving portion when coupling a torque receiving portion for transmitting torque with a leaf spring. It is another object of the present invention to provide a torque measuring device socket which can be manufactured at a low cost with a relatively simple structure.

[0013]

SUMMARY OF THE INVENTION In order to overcome the above-mentioned problems and achieve the desired object, the present invention provides a hollow cylindrical socket body which is disposed in a casing of a torque measuring device and is rotatable with respect to the casing. A socket portion provided at an upper end of the socket body, facing the upper surface of the casing, and detachably engaged with a torque transmitting portion of various tightening tools;
A torque receiving portion is provided at the lower end of the socket main body and faces the lower surface of the casing, and one end includes a torque receiving portion coupled to the other end of a leaf spring supported by a part of the casing. In a socket of a torque measuring device, wherein a stress strain generated in the leaf spring by the transmitted torque is measured by a strain gauge provided at a predetermined position of the leaf spring, a cylinder is provided at a lower end opening of the hollow cylindrical socket body. A pair of split grooves, which are recessed so as to intersect with the axis and allow insertion of the leaf spring, are provided at the base end deeper than the pair of split grooves, and have a diameter larger than the groove width of the split grooves. The leaf spring and the socket main body, which are formed by an expanded base end portion and are fitted and held in the split grooves, are configured to be commonly tightened and fixed by an appropriate tightening tool.

[0014] In this case, it is preferable that the fastener is constituted by a bolt and a nut. An expanded base end formed at a base end of a pair of split grooves formed in the socket body of the torque receiving portion to have a diameter larger than the groove width has upper and lower ends of one end of a leaf spring clamped and fixed to the split groove. In this case, when unbalanced stress strain is about to occur, the socket body is appropriately and flexibly deformed, and functions so that the stress strain is always evenly distributed to one end of the leaf spring.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a socket of a torque measuring device according to the present invention.

FIGS. 1 and 2 show an embodiment of a socket for a torque measuring device according to the present invention. FIG. 1 is a plan view of a main torque measuring mechanism portion which is a main portion of the torque measuring device. FIG. 2A is a front view of the main torque measuring mechanism, and FIG. 2B is a right side view of the main torque measuring mechanism.

In FIG. 1 and FIG. 2, a main torque measuring mechanism 30 of the torque detector includes a socket portion 32 which engages with a torque transmitting portion (rotary shaft portion) of a tightening tool, and an integral portion of the socket portion 32. A torque receiving portion 36 is provided, which is combined with a socket body 34 that receives the torque by being coaxially arranged with the torque transmitting portion of the tightening tool. Therefore, the torque receiving portion 36 is rotatably supported by an appropriate casing 41 via a bearing 38, and is configured and arranged such that the socket portion 32 is exposed to the outside of the casing 41.

On the other hand, the socket body 34 of the torque receiving portion 36 is located inside the casing, and has one end supported at a fulcrum F by a supporting member (not shown) fixed inside the casing. It is configured and arranged to lock the other end of 40. A strain gauge 42 is attached to a part of the leaf spring 40 close to the socket body 34 side.

In the torque measuring device thus constructed, the torque transmitting portion of the tightening tool is engaged with the socket portion 32 of the torque receiving portion 36 to transmit the torque, so that the socket body 34 of the torque receiving portion 36 is transmitted. Is transmitted to the socket body 34, and receives the torque that causes the socket body 34 to rotate in a predetermined direction. The torque associated with the rotation of the socket body 34 causes a required stress distortion at the other end of the leaf spring 40. Therefore, the magnitude of the stress strain generated in the leaf spring 40 is appropriately determined by the strain gauge 4.
2, the torque can be measured as a torque value in the torque transmitting portion of the tightening tool. The above configuration and its function are basically the same as those of the conventional torque detector shown in FIG.

However, in the torque measuring instrument according to the present invention, as shown in FIGS. 2A and 2B, the hollow cylindrical main body 34 of the torque receiving portion 36 intersects the cylindrical axis thereof. Fixed width (leaf spring 4
0), a pair of split grooves 35, 35
Are formed. Further, the base ends of the split grooves 35, 35 have a larger diameter (about 2 to 3) than the groove width w1 of the split grooves 35, 35.
× w1) to form the expanded base end portions 39, 39.

One end 40a of the leaf spring 40 is inserted into the split grooves 35, 35 of the socket body 34 of the torque receiving portion 36 thus configured, and intersects with the split grooves 25, 25 and the leaf spring 40 The upper and lower central portions are commonly penetrated, and fastening is performed with a fastener including, for example, a bolt 37a and a nut 37b. Thereby, the leaf spring 4
The one end 40a of the "0" is clamped and fixed in the split grooves 25, 25 in a state of evenly abutting. As a result, the respective portions of the leaf spring 40 clamped and fixed in the split grooves 25, 25, that is, the contact state between one portion x1, x2 and the other portion x3, x4 becomes uniform, and the stress applied to the leaf spring 40 becomes equal. The variance of the distortion can be balanced.

According to the socket of the torque measuring device according to this configuration, when the torque receiving portion 36 of the main torque measuring mechanism 30 and the leaf spring 40 are connected, one end 40a of the leaf spring 40
Are the split grooves 35, 3 of the socket body 34 of the torque receiving portion 36.
5 is fixed so that the stress strain is evenly distributed.
Therefore, the stress distortion generated in the leaf spring 40 due to the torque transmitted to the socket body 34 of the torque receiving portion 36 is:
Appropriately corresponding to the torque value, high-accuracy torque measurement can be achieved.

In the socket of the torque measuring instrument according to the present invention, the base ends of the split grooves 35, 35 are formed as expanded base end portions 39, 39 formed with a diameter larger than the groove width. When unbalanced stress distortion is generated at the upper and lower ends x1, x2, x3, x4 of the one end 40a of the leaf spring 40 held between the split grooves 35, 35, respectively.
The socket body 34 can be properly and flexibly deformed so that the one end 40a of the leaf spring 40 can be clamped so that stress and strain are always evenly distributed.

[0024]

As is apparent from the above-described embodiment, the socket of the torque measuring device according to the present invention is disposed in the casing of the torque measuring device, and has a hollow cylindrical socket body rotatable with respect to the casing; A socket portion provided at an upper end of the socket body and facing the upper surface of the casing and detachably engaged with a torque transmitting portion of various tightening tools; and a socket portion provided at a lower end of the socket body and facing the lower surface of the casing. A torque receiving portion coupled at one end to the other end of the leaf spring supported by a part of the casing, and the stress distortion generated in the leaf spring by the torque transmitted from the tightening tool to the socket portion is reduced. In a socket of a torque measuring device which is measured by a strain gauge provided at a predetermined position of a leaf spring, the socket is provided at a lower end opening of the hollow cylindrical socket body. A pair of split grooves, which are recessed so as to intersect the cylinder axis and allow insertion of the leaf spring, are provided at the base end deeper than the pair of split grooves, and have a diameter larger than the groove width of the split groove. And the socket body is fixed to the socket body by a suitable tightening tool. It is possible to uniformly disperse the stress strain applied to the spring and perform a highly accurate torque measurement.

According to the socket of the torque measuring device according to the present invention, the pair of split grooves provided for coupling the leaf spring to the socket body of the torque receiving portion is formed at the base end of each split groove. By providing an expanded base end formed to have a diameter larger than the groove width, when unbalanced stress distortion is to be generated at each of the upper and lower ends of one end of the leaf spring clamped and fixed to the split groove, The socket body is appropriately and flexibly deformed, and the one end of the leaf spring can be clamped so that the stress and strain are always evenly distributed, so that a more accurate torque measurement can be performed. Moreover, the socket of the torque measuring device according to the present invention has many excellent advantages, such as being able to be manufactured at a low cost with a relatively simple configuration.

[Brief description of the drawings]

FIG. 1 is a plan view of a main torque measuring mechanism showing one embodiment of a socket of a torque measuring device according to the present invention.

2A is a front view of a main torque measuring mechanism of the socket in the torque measuring device shown in FIG. 1, and FIG. 2B is a right side view of the main torque measuring mechanism shown in FIG.

FIG. 3 is a schematic perspective view showing a main torque measuring mechanism of a conventional torque measuring device and a peripheral mechanism thereof.

4A is a front view of a main torque measuring mechanism in a socket of a conventional torque measuring device, and FIG. 4B is a right side view of the main torque measuring mechanism shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 30 Main torque measuring mechanism part 32 Socket part 34 Socket main body 35 Split groove 36 Torque receiving part 37a, 37b Bolt / nut 38 Bearing 39 Expansion base end of split groove 40 Leaf spring 40a Fixed end of leaf spring 42 Strain gauge F Support point

Claims (2)

[Claims] 1. A hollow cylindrical socket body (34) arranged on a casing (41) of a torque measuring device and rotatable with respect to the casing (41), and provided at an upper end of the socket body (34). A socket portion which faces the upper surface of the casing (41) and is detachably engaged with the torque transmitting portions of various tightening tools.
(32), provided at the lower end of the socket body (34), facing the lower surface of the casing (41), one end of the casing (41).
And a torque receiving portion (36) coupled to the other end of the leaf spring (40) supported on a part of the leaf spring (40) by the torque transmitted from the tightening tool to the socket portion (32). In the socket of the torque measuring device which is designed to measure the stress strain generated by the strain gauge (42) provided at a predetermined position of the leaf spring (40), the lower end opening of the hollow cylindrical socket body (34) A pair of split grooves (35, 35), which are recessed so as to intersect the cylindrical axis and allow the insertion of the leaf spring (40), are provided at the deepened base ends of the pair of split grooves (35, 35). Provided,
The expanding base end (39,3) having a diameter larger than the groove width of the split groove (35,35)
9), and the leaf spring (40) and the socket body (34) fitted and clamped in the split grooves (35, 35) are commonly tightened and fixed by an appropriate fastener (37). A socket for a torque measuring device, characterized in that it is configured as described above. 2. The torque measuring instrument socket according to claim 1, wherein said fastener comprises a bolt and a nut.