JP2003083824A - Torquemeter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a torquemeter easily mountable on a rotating driving machine, easily formable in a sealed structure, and having an excellent waterproof mechanism, durability and reliability. SOLUTION: This torquemeter 10 is equipped with a tabular elastic body 15 mounted between a flange provided on the rotating driving machine and a rotating driving structure, and having on the center part a center through hole 16 through which an output axis of the rotating driving machine is passed. The torquemeter is constituted as follows: circular holes 20 are bored on torque transmission parts 19 formed by combining flange fixing parts 11 with base fixing parts 12; a ring groove 22 for connecting respectively lead wire through holes 21 penetrating the circular holes 20 and the center through hole 16, for wiring lead wires is formed; each opening part of the circular holes 20, the lead wire through holes 21 and the ring groove 22 is sealed by a sealing material 24; strain gages SG are bonded on the inside faces 20a of the circular holes 20; and thereby the strain caused by the torque working on the torque transmission part 19 is measured and the driving torque generated on the output axis is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque meter,
More specifically, it is easily attached to a rotary drive machine such as an electric motor or a speed reducer having a flange to improve the accuracy of measurement of the drive torque generated on the output shaft.

[0002]

2. Description of the Related Art The number of rotary drive structures driven by a rotary drive force from a rotary drive machine is very large, and in controlling and monitoring the states of these structures, measurement of drive torque generated on an output shaft transmitting the drive force. Is very important. Currently, various torque meters are provided. Among them, most of the torque meters using strain gauges are shown in FIG.
As shown in (B), a torque gauge 100 having a shaft-shaped elastic body 4 to which a strain gauge 3 is bonded is provided in the middle of the torque transmission shaft 2 of the rotary drive machine 1, and the strain generated by the transmission torque is detected. Is adopted.

As described above, in most torque meters using strain gauges, a method of detecting a strain caused by a transmission torque by connecting a shaft-shaped elastic body having a strain gauge adhered in the middle of a torque transmission shaft of a rotary drive machine. In such a torque meter, since the shaft-shaped elastic body is connected to the rotary shaft via the coupling, an extra space is required in the axial direction. Further, contact type or non-contact type signal transmitting means such as a slip ring is required to take out a signal from the rotary shaft, but these signal transmitting means are expensive,
Moreover, since it is attached to the rotary shaft and rotated, it is difficult to make the strain detection part into a sealed structure and a waterproof structure, and there are problems in terms of durability and reliability.

On the other hand, JP-A-62-112023
In JP-A No. 2004-242, instead of directly detecting the torque of the rotating shaft as described above, a method of measuring the restraint torque which is the reaction force of the driving torque via the housing of the driving device such as the electric motor is proposed.

Further, the present applicant has filed Japanese Patent Application Laid-Open No. 11-1832.
In No. 77, the drive torque is detected by detecting the restraint torque which is a reaction force of the drive torque via the housing of the drive device such as the electric motor, instead of directly detecting the torque of the rotating shaft. Proposing a torque meter.

Further, in Japanese Unexamined Patent Publication No. 8-35895, the strain measuring means is composed of first and second parts connected to each other so that torque is transmitted by a torque transmitting member to which the strain measuring means is attached. A signal corresponding to the torque transmitted by the member is generated and supplied to the wireless transmission unit. A torque display device has been proposed in which the wireless transmission unit transmits a signal according to the torque to the wireless reception unit, and the wireless reception unit performs display according to the torque transmitted by the torque transmission member.

[0007]

However, in the torque detecting device disclosed in Japanese Patent Laid-Open No. 61-212023, a casing of an electric motor or the like needs to be additionally processed or a special metal fitting is required in order to obtain the restraint torque. However, there is a problem in that it is not easy to use as a general-purpose torque meter, and it is difficult to seal a waterproof mechanism.

The torque meter of Japanese Patent Laid-Open No. 11-183277 incorporates a torque meter between an electric motor having mounting legs and a fixed base to detect the torque of the output shaft. It is difficult to apply it to a motor with a built-in motor, and the mounting posture is limited, so there is still room for improvement in the space for mounting the motor.

Further, since the torque display device of Japanese Patent Laid-Open No. 8-35895 is not directly connected to the flange, an extra space is required for mounting, and it is troublesome to connect with the rotary drive machine. There is. Further, in order to have a waterproof mechanism, it is necessary to cover the entire gauge, lead wire, etc. with resin or the like, which poses a problem that it is difficult to seal.

The present invention has been made in view of the above-mentioned problems and does not require any special processing to be attached to a rotary drive machine such as an electric motor or a speed reducer, and can be easily attached.
It is an object of the present invention to provide a torque meter that can easily have a closed structure, has an excellent waterproof mechanism, and has excellent durability and reliability.

[0011]

In order to solve the above problems, the present invention provides a torque meter for detecting a drive torque generated in an output shaft of a rotary drive machine for driving a rotary drive structure by a rotary drive force. , A plate-like elastic body that is mounted between a flange provided on the rotary drive machine and the rotary drive structure and has a central through hole at the center through which the output shaft of the rotary drive machine passes, and the central through hole A torque transmission in which a flange fixing portion provided around the periphery of the flange and having a fastening means for the flange and a base fixing portion provided outside the flange fixing portion and having a fastening means for the fixed base of the rotary drive structure are coupled to each other. An annular groove is formed which has a plurality of circular holes drilled in a portion, and which connects the plurality of lead wire through holes that penetrate the circular hole and the center through hole and lead wires are wired, respectively. Round , The lead wire through hole, and each opening of the annular groove are sealed with a sealing material, and the strain gauge connected to the lead wire is adhered to the inner surface of the circular hole, and the torque acting on the torque transmitting portion is The present invention provides a torque meter characterized in that the strain due to is measured and the drive torque generated in the output shaft is detected.

As described above, since the torque meter can be directly attached to the flange of the rotary drive machine such as the prime mover and the speed reducer by the fixing means such as the fixing bolt, the mounting is easy and the space in the axial direction is omitted. Can be converted. Further, since each opening is configured to be easily sealed by a diaphragm such as a metal or resin and a sealing material such as a cover, it is possible to perform sealing treatment and improve the waterproof function. Further, since the torque meter does not rotate, durability and measurement reliability can be improved. Therefore, by measuring the strain with the strain gauge, the drive torque generated on the output shaft can be detected very accurately under any measurement environment.

It is preferable that the circular hole penetrates the plate-like elastic body from the side of the rotary drive toward the side of the rotary drive structure, and a strain gauge is bonded to the inner peripheral surface of the circular hole. With the above configuration, it is possible to accurately measure the strain due to the low torque generated in the thin portion in particular.

The circular holes are drilled respectively from the rotary drive side and the rotary drive structure side of the plate-like elastic body, have circular bottom surfaces that do not penetrate each other, and a strain gauge is bonded to the bottom surfaces. Is preferred. With the above configuration, shear strain can be measured, and particularly high torque with high rigidity can be accurately measured. As described above, by appropriately setting the shape of the circular hole and the bonding position of the strain gauge according to the torque to be measured, the strain in various directions can be measured, so that the versatility of the torque meter can be enhanced.

It is preferable that the torque transmitting portion where the flange fixing portion and the base fixing portion are coupled is two or more, preferably four or more. Further, it is desirable that the plurality of torque transmitting portions are arranged symmetrically with respect to the central through hole, and that the strain gauges are designed so as to have substantially the same strain. This makes it possible to obtain a stable output proportional to the torque.

The strain gauge is adhered to the inside of the circular hole, and the Wheatstone bridge circuit formed by connecting the strain gauges is connected by using the lead wire through hole penetrating the inside of the elastic body. Since the cable lead-out port for sending the lead wire is provided at one end of the through hole for use, the cover and the diaphragm facilitate the sealing structure. Moreover, the signal line can be easily taken out from the cable lead-out port even though the structure is hermetically closed. The sealing method includes a method of covering with wax or resin having a waterproof effect and a method of welding and sealing using a metal diaphragm or a metal cover.

It is preferable that the torque transmitting portion is formed by a part of a fan shape centered on the center of the center through hole, and inside the circular hole of the thin portion formed between the fan shape and the circular hole. It is preferable that the strain gauges are bonded to each other so that the strain is detected. As a result, it is possible to obtain a torque output by appropriately concentrating the strain in the vicinity of the thin portion while suppressing the reduction in rigidity due to the deformation of the torque transmitting portion. Further, since the center of the fan shape coincides with the center of rotation of the torque, the radial displacement of the thin portion becomes minimal, and the strain caused by the rotational displacement due to the torque can be maximized. You can get the output.

Further, the plate-like elastic body may have various shapes such as a circular shape and a rectangular shape depending on the shape and use of the rotary drive machine or the rotary drive structure. The fixing means is preferably a bolt, and is preferably arranged symmetrically with respect to the central position of the central through hole. Thereby, the measurement accuracy can be further improved. A plate-shaped or sheet-shaped material may be interposed between the flange and the plate-shaped elastic body.

[0019]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a torque meter 10 according to a first embodiment, which includes a flange fixing portion 11 and a base fixing portion 1.
A rotary drive machine 1 in which the strain due to the torque acting between the two is measured, and the rotary drive structure 13 is driven by the rotary drive force.
The driving torque generated in the output shaft 14A of No. 4 is detected.

In the torque meter 10, a plate-like elastic body 15 made of metal such as aluminum is mounted between the flange 14B provided on the rotary drive machine 14 and the rotary drive structure 13. The plate-like elastic body 15 is made of a circular flat plate having a required thickness, and its upper and lower surfaces are parallel to each other. A central through hole 16 through which the output shaft 14A of the rotary drive machine 14 passes at the center of the plate-like elastic body 15.
And a bolt hole 17 (17A to 1A) around the center through hole 16 as a fastening means with the flange 14B.
7D) has a flange fixing portion 11 vertically provided. Further, on the outer peripheral side of the flange fixing portion 11, bolt fixing holes 18 (18A to 18D) are vertically provided as fastening means for fastening the fixed base 13A of the rotary structure 13 to the base fixing portion 12.
Is provided. For the bolt holes 17 and 18, bolt B
Is inserted and tightened and fixed.

Four torque transmitting portions 19 for connecting the flange fixing portion 11 and the base fixing portion 12 to transmit torque are provided symmetrically with respect to the center of the central through hole 16, and each torque transmitting portion 19 is provided. Is formed by a fan-shaped part centered on the center of the center through hole 16. Four circular holes 20 (20A to 20D) are provided in the center of the torque transmitting portion 19.
Is drilled in the axial direction. Further, the circular hole 20 and the central through hole 16 are penetrated, and the lead wire through hole 21 through which the lead wire is wired is opened in the radial direction of the circular plate-shaped elastic body 15. An annular groove 22 that connects a plurality of lead wire through holes 21 is formed inside the flange fixing portion 11 in an annular shape having the same center as the center through hole 16.

A cable lead-out port 23 for sending the lead wire is provided at one end of the lead wire through hole 21, and the circular hole 20, the annular groove 22 and the lead wire through hole 21 have openings such as a metal diaphragm or a cover. It is sealed with a sealing material 24 consisting of. Although each opening is sealed by the sealing material 24, the signal line 32 is taken out from the cable outlet 23 so that it can be connected to the detector 31. The circular hole 20 penetrates the plate-shaped elastic body 15 from the rotary drive 14 side toward the rotary drive structure 13 side, and the strain gauge SG (S (S) is connected to the lead wire on the inner peripheral surface 20a of the circular hole 20.
G1 to SG8) are bonded.

Strain gauges SG (SG1 to SG8) are connected as shown in FIG. 4, and the Wheatstone bridge circuit 3 is connected.
Forming 0. The output line of the Wheatstone bridge circuit 30 is drawn from the plate-like elastic body 15 and connected to the detector 31. In this way, the strain due to the torque acting on the thin portion 19a of the torque transmitting portion 19 is measured, and the output shaft 14
The drive torque generated in A is detected.

With the above structure, the torque meter 10 is attached to the flange 14B of the rotary drive machine 14 such as a prime mover and a speed reducer.
Can be attached directly with the fixing bolt B, so that the attachment is easy and the space in the axial direction can be omitted. Further, since each opening is sealed by the sealing material 24 including a metal diaphragm and a cover, it is possible to perform sealing treatment and improve the waterproof function. Further, since the torque meter 10 itself does not rotate, it is possible to prevent wear of members such as the strain gauge SG due to friction during rotation, and it is possible to improve durability and reliability of measurement. Therefore, the drive torque generated in the output shaft 14A can be detected very accurately.

FIG. 5 is a torque meter 1 according to a modification of the first embodiment.
0'is shown, and the plate-like elastic body 15 'of the torque meter 10' has a rectangular shape. The rotary driving machine is bolted to the rotary drive structure through the bolt holes 17 ′ of the flange fixing portion 11 ′, and the rotary drive structure is bolted to the rotary driving structure through the bolt holes 18 ′ of the base fixing portion 12 ′. A center through hole 16 'is provided at the center of the plate-like elastic body 15', and an annular groove 22 'is provided around the center through hole 16'.
A base fixing portion 12 'is provided outside the flange fixing portion 11', and a portion connecting the two is used as a torque transmitting portion 19 '. Two circular holes 20 '(20A', 20B ') are vertically provided at the center of the torque transmitting portion 19' so as to penetrate the plate-like elastic body 15 '. Circular hole 20 '
A strain gauge SG 'is bonded to the inner peripheral surface 20a' of the. Further, the openings such as the circular holes 20 'are configured so that they can be sealed by the sealing material 24' as in the first embodiment.

As described above, even if the plate-like elastic body 15 'is formed in the rectangular shape, the torque generated in the output shaft can be detected and the flange can be easily obtained by the above-described structure. Since it can be fixed to and has a sufficient sealing function, it can also have a waterproof function.

FIG. 6 shows a torque meter 40 according to the second embodiment, in which the four circular holes 50 of the torque meter 40 are formed by the plate-like elastic body 4.
5, the rotary driving machine side and the rotary driving structure side are respectively drilled, and have circular bottom surfaces 50a that do not penetrate each other.
The strain gauges SG (SG11 to SG18) are adhered to. With the above configuration, shear strain can be measured, and particularly high torque with high rigidity can be accurately measured.

The torque meter of the present invention can have various forms other than the above-mentioned embodiment according to the torque to be detected, the type of rotary drive machine, etc., and can be easily attached to the rotary drive machine. A waterproof structure that can be hermetically sealed and a structure that can accurately detect torque may be used.

[0029]

As is apparent from the above description, according to the present invention, a torque meter can be directly attached to the flange of a rotary drive machine such as a prime mover or a speed reducer having a flange by a fixing means such as a fixing bolt. Therefore, the mounting is easy, and space loss at the time of mounting in the axial direction can be omitted. Further, since each opening is configured to be easily sealed by a sealing material such as a diaphragm made of metal or resin and a cover, it is possible to perform a sealing treatment having a sealed structure and improve the waterproof function. Further, since the torque meter does not rotate, durability and measurement reliability can be improved.

Therefore, by measuring the strain with the strain gauge, the drive torque generated on the output shaft can be detected very accurately under any measurement environment. Therefore, it becomes possible to measure the torque in the fields that could not be applied so far, and it is possible to realize stable operation and quality improvement of the product by monitoring the torque.

Further, by appropriately setting the shape of the circular hole and the bonding position of the strain gauge according to the torque to be measured,
Since the strains in various directions can be measured, it is possible to adopt a configuration according to the torque to be detected, such as low torque or high torque, and enhance the versatility of the torque meter.

[Brief description of drawings]

FIG. 1 is a diagram showing a mounting state of a torque meter according to a first embodiment of the present invention, a rotary drive machine, and a rotary drive structure.

FIG. 2 is a perspective view of a plate-shaped elastic body of the torque meter according to the first embodiment.

3A and 3B are respectively a front view and a side view of the torque meter of the first embodiment as viewed from the direction of the arrow.

FIG. 4 is a diagram showing a Wheatstone bridge circuit of the torque meter of the first embodiment.

5A and 5B are diagrams showing a modification of the first embodiment.

6A and 6B are diagrams showing a torque meter according to a second embodiment.

7A and 7B are diagrams showing a conventional example.

[Explanation of symbols]

10 Torque meter 11 Flange fixing part 12 Base fixing part 13 Rotary drive structure 14 rotary drive 14A output shaft 14B flange 15 Plate-like elastic body 16 Center through hole 17, 18 bolt holes 19 Torque transmission part 20 circular holes 21 Through hole for lead wire 22 annular groove 23 Cable outlet 24 Sealant 30 Wheatstone bridge circuit SG strain gauge B bolt

Claims (4)

[Claims] 1. A torque meter for detecting a drive torque generated in an output shaft of a rotary drive machine for driving the rotary drive structure by a rotary drive force, the flange being provided on the rotary drive machine and the rotary drive structure. And a plate-like elastic body having a central through hole through which the output shaft of the rotary drive device passes, the flange fixing being provided around the central through hole and having fastening means with the flange. A plurality of circular holes drilled in a torque transmitting portion to which a base portion and a base fixing portion provided outside the flange fixing portion and having a fastening means for fastening to the fixed base of the rotary drive structure are coupled, An annular groove is formed to connect a plurality of lead wire through holes through which a lead wire is pierced through the circular hole and the center through hole, and the openings of the circular hole, the lead wire through hole, and the annular groove are formed. Part is sealed While being sealed with a material, a strain gauge connected to the lead wire is adhered to the inner surface of the circular hole, the strain due to the torque acting on the torque transmitting portion is measured, and the driving torque generated on the output shaft is detected. Torque meter characterized by having. 2. The circular hole penetrates the plate-like elastic body from the rotary drive side toward the rotary drive structure side, and a strain gauge is bonded to the inner peripheral surface of the circular hole. Torque meter described in. 3. The circular holes are drilled respectively from the rotary drive side and the rotary drive structure side of the plate-like elastic body, have circular bottom surfaces that do not penetrate each other, and a strain gauge is bonded to the bottom surfaces. The torque meter according to claim 1, wherein 4. The torque transmitting portion is arranged symmetrically with respect to a central position of the central through hole.
The torque meter according to any one of claims 1 to 3.