JP4836370B2 - Torque meter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a torque meter, and more particularly, to improve the measurement accuracy of drive torque generated on an output shaft by being easily attached to a rotary drive machine such as an electric motor or a speed reducer having a flange.
[0002]
[Prior art]
The number of rotary drive structures driven by the rotary drive force from the rotary drive machine is very large, and in controlling and monitoring these structures, it is very important to measure the drive torque generated on the output shaft that transmits the drive force. is there. Currently, various torque meters are provided. Among them, most of the torque meters using strain gauges are the torque transmission shaft 2 of the rotary drive machine 1 as shown in FIGS. In the middle of this, a method is adopted in which a torque meter 100 connected with a shaft-like elastic body 4 to which a strain gauge 3 is bonded is interposed to detect strain caused by transmission torque.
[0003]
As described above, most of the torque meters using strain gauges use a method of detecting strain caused by transmission torque by connecting a shaft-like elastic body with a strain gauge bonded to the middle of the torque transmission shaft of a rotary drive. In such a torque meter, an extra space is required in the axial direction because the shaft-like elastic body is connected to the rotating shaft via a coupling. Further, in order to take out a signal from the rotating shaft, a contact type or non-contact type signal transmitting means such as a slip ring is required. However, these signal transmitting means are expensive and are attached to the rotating shaft for rotation. In addition, it is difficult to make the strain detection part into a waterproof structure with a sealed structure, and there are difficulties in terms of durability and reliability.
[0004]
On the other hand, in JP-A-62-112023, instead of directly detecting the torque of the rotating shaft as described above, a restraining torque that is a reaction force of the driving torque is provided via the housing of a driving device such as an electric motor. A method of measuring has been proposed.
[0005]
Further, the present applicant does not directly detect the torque of the rotating shaft described above in Japanese Patent Laid-Open No. 11-183277, but detects a restraining torque that is a reaction force of the driving torque via a housing of a driving device such as an electric motor. Thus, a torque meter configured to detect the driving torque is proposed.
[0006]
Further, in Japanese Patent Laid-Open No. 8-35895, the first and second parts are connected in such a manner that torque is transmitted by a torque transmission member to which the strain measurement means is attached. The strain measurement means is transmitted by the torque transmission member. A signal corresponding to the torque to be generated 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 corresponding to torque to the wireless reception unit, and the wireless reception unit displays according to the torque transmitted by the torque transmission member.
[0007]
[Problems to be solved by the invention]
However, in the torque detector disclosed in Japanese Patent Application Laid-Open No. 62-112203, a general-purpose torque meter is not easy to install because additional work is required on the casing of an electric motor or the like, or special metal fittings are required to obtain a binding torque. However, there is a problem that it is difficult to perform a seal for providing a waterproof mechanism.
[0008]
In addition, the torque meter disclosed in Japanese Patent Application Laid-Open No. 11-183277 incorporates a torque meter between a motor having a mounting leg and a fixed base to detect the torque of the output shaft. Is difficult to apply, the mounting orientation is limited, and there is still room for improvement in the mounting space with the motor and the like.
[0009]
Furthermore, since the torque display device disclosed in Japanese Patent Application Laid-Open No. 8-35895 is not directly connected to the flange, there is a problem that extra space is required for attachment and that connection with the rotary drive device is troublesome. Furthermore, in order to provide a waterproof mechanism, it is necessary to cover the entire gauge, lead wire, etc. with resin or the like, and there is a problem that it is difficult to perform sealing.
[0010]
The present invention has been made in view of the above-described problems, and does not require special processing for attachment to a rotary drive machine such as an electric motor or a speed reducer, is easy to attach, and easily has a sealed structure. Therefore, it is an object to provide a torque meter that is excellent in a waterproof mechanism and has excellent durability and reliability.
[0011]
[Means for Solving the Problems]
In order to solve the above problems, the present invention is a torque meter for detecting a drive torque generated on an output shaft of a rotary drive machine that drives a rotary drive structure with a rotary drive force,
A plate-like elastic body that is mounted between a flange provided in the rotary drive and the rotary drive structure and has a central through hole through which an output shaft of the rotary drive passes in the center,
A flange fixing portion provided around the center through hole and having fastening means with the flange ;
A base over scan fixing portion is a portion that does not rotate is fastened in a fixed base and concluded means above Symbol rotary drive structure by a rotational driving force of said rotary drive unit with which we provided outside of the flange fixing unit,
A torque transmitting portion in which the flange fixing portion and the base fixing portion are coupled ;
It has a plurality of circular holes drilled in the torque transmission part ,
Each of the circular hole, the lead wire through hole, and the annular groove is formed by connecting a plurality of lead wire through holes through which the lead wire is routed through the circular hole and the central through hole. The opening is sealed with a sealing material, and a strain gauge connected to the lead wire is bonded to the inner surface of the circular hole. The strain due to the torque acting on the torque transmitting portion is measured, and the drive torque generated on the output shaft is There is provided a torque meter characterized by being configured to be detected.
[0012]
As described above, since the torque meter can be directly attached to the flange of a rotary drive machine such as a prime mover or a speed reducer by a fixing means such as a fixing bolt, it is easy to attach and the axial space is also omitted. Can do. Moreover, since each opening part is made into the structure which can be easily sealed with sealing materials, such as diaphragms and covers, such as a metal and resin, a sealing process can be performed and a waterproof function can be improved. 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 driving torque generated in the output shaft can be detected with high accuracy in any measurement environment.
[0013]
It is preferable that the circular hole penetrates the plate-like elastic body from the rotary drive side to the rotary drive structure side, and a strain gauge is bonded to the inner peripheral surface of the circular hole. By setting it as the said structure, the distortion by the low torque which arises especially in a thin part can be measured with a sufficient precision.
[0014]
The circular holes are preferably drilled from the rotary drive side and the rotary drive structure side of the plate-like elastic body, have a circular bottom surface that does not penetrate each other, and a strain gauge is bonded to the bottom surface. By setting it as the said structure, a shear strain can be measured and the high torque especially high rigidity can be measured with a sufficient precision.
Thus, since the distortion of a various direction can be measured by setting suitably the shape of a circular hole and the adhesion position of a strain gauge according to the torque to measure, the versatility of a torque meter can be improved.
[0015]
It is preferable that the torque transmission part where the flange fixing part and the base fixing part are coupled is two or more, preferably four or more. In addition, it is desirable that the plurality of torque transmitting portions be arranged symmetrically with respect to the central through hole and designed so that each strain gauge has substantially the same strain. As a result, a stable output proportional to the torque can be obtained.
[0016]
The strain gauge is bonded to the inside of the circular hole, and the Wheatstone bridge circuit formed by connecting the strain gauge is connected using the lead wire through hole penetrating the inside of the elastic body, and the lead wire through hole is formed. Since one end of the cable is provided with a cable lead-out port for sending a lead wire, a sealed structure is easy with a cover or a diaphragm. In addition, the signal line can be easily taken out from the cable lead-out port while having a sealed structure. There are two sealing methods: a method of covering with a waterproofing wax or resin, and a method of welding and sealing using a metal diaphragm or a metal cover.
[0017]
The torque transmitting portion is preferably formed as a part of a fan shape centered on the center of the center through hole, and a strain gauge is provided inside the thin circular hole formed between the fan shape and the circular hole. It is preferable to have a structure for bonding and detecting strain. Accordingly, it is possible to obtain a torque output by appropriately concentrating strain in the vicinity of the thin portion while suppressing a decrease in rigidity due to deformation of the torque transmitting portion. In addition, since the center of the fan shape coincides with the rotation center of the torque, the radial displacement of the thin wall portion is minimized, and the distortion caused by the rotational displacement due to the torque can be maximized. Output can be obtained.
[0018]
Further, the plate-like elastic body can have various shapes such as a circular shape or a rectangular shape depending on the shape and application of the rotary drive machine or the rotary drive structure. The fixing means is preferably a bolt, and is preferably arranged at a symmetrical position with respect to the center position of the central through hole. Thereby, measurement accuracy can be further improved. A plate-like or sheet-like material may be interposed between the flange and the plate-like elastic body.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 3 show a torque meter 10 according to the first embodiment, in which distortion due to torque acting between the flange fixing portion 11 and the base fixing portion 12 is measured, and the rotation driving structure 13 drives the rotation driving structure 13 with the rotation driving force. The drive torque generated on the output shaft 14A of the machine 14 is detected.
[0020]
In the torque meter 10, a plate-like elastic body 15 made of metal such as aluminum is mounted between a flange 14 </ b> B provided in the rotary drive machine 14 and the rotary drive structure 13. The plate-like elastic body 15 is a circular flat plate having a required thickness, and the upper and lower surfaces thereof are parallel to each other. A central through hole 16 through which the output shaft 14A of the rotary driving machine 14 passes is provided at the center of the plate-like elastic body 15, and a bolt hole 17 (17A to 17D) is provided around the central through hole 16 as a fastening means with the flange 14B. ) Is provided in a flange fixing portion 11. Further, on the outer peripheral side of the flange fixing portion 11, a base fixing portion 12 in which bolt holes 18 (18 </ b> A to 18 </ b> D) are suspended is provided as a fastening means with the fixing base 13 </ b> A of the rotating structure 13. Bolts B are inserted into the bolt holes 17 and 18 and fastened.
[0021]
Four torque transmission parts 19 for transmitting torque by coupling between the flange fixing part 11 and the base fixing part 12 are provided symmetrically about the center of the center through hole 16, and each torque transmission part 19 passes through the center. It is formed of a part of a fan shape centering on the center of the hole 16. Four circular holes 20 (20A to 20D) are drilled in the axial direction at the center of the torque transmitting portion 19. Further, the circular hole 20 and the central through hole 16 are penetrated, and a lead wire through hole 21 through which the lead wire is wired is opened toward the radial direction of the circular plate-like 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 the same shape as the center through hole 16 in an annular shape.
[0022]
One end of the lead wire through hole 21 is provided with a cable lead-out port 23 through which the lead wire is sent. The circular hole 20, the annular groove 22, and the opening of the lead wire through hole 21 are hermetically sealed with a metal diaphragm or a cover. It is sealed with a material 24. Each opening is sealed with a sealing material 24, but can be connected to the detector 31 by taking out the signal line 32 from the cable outlet 23. The circular hole 20 passes through the plate-like elastic body 15 from the rotary drive 14 side to the rotary drive structure 13 side, and a strain gauge SG (SG1) connected to a lead wire on the inner peripheral surface 20a of the circular hole 20. To SG8) are adhered.
[0023]
Strain gauges SG (SG1 to SG8) are connected as shown in FIG. 4 to form a Wheatstone bridge circuit 30. The output line of the Wheatstone bridge circuit 30 is drawn from the plate-like elastic body 15 and connected to the detector 31. As described above, the distortion due to the torque acting on the thin portion 19a of the torque transmitting portion 19 is measured, and the driving torque generated in the output shaft 14A is detected.
[0024]
With the above configuration, the torque meter 10 can be directly attached to the flange 14B of the rotary drive machine 14 such as a prime mover or a speed reducer with the fixing bolt B, so that the attachment is easy and the axial space is also omitted. Can be Moreover, since each opening part is sealed with the sealing material 24 which consists of a metal diaphragm and a cover, a sealing process can be performed and a waterproof function can be improved. Further, since the torque meter 10 itself does not rotate, wear of members such as the strain gauge SG can be prevented by friction during rotation, and durability and measurement reliability can be improved. Therefore, the driving torque generated in the output shaft 14A can be detected with very high accuracy.
[0025]
FIG. 5 shows a torque meter 10 ′ according to a modification of the first embodiment, and the plate-like elastic body 15 ′ of the torque meter 10 ′ has a rectangular (rectangular) shape. The rotary drive unit is bolted to the rotary drive structure through the bolt hole 17 ′ of the flange fixing portion 11 ′, and the rotary drive structure is bolted to the bolt hole 18 ′ of the base fixing portion 12 ′. A central 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 transmission portion 19 ′. Two circular holes 20 '(20A', 20B ') are suspended from the center of the torque transmitting portion 19' so as to penetrate the plate-like elastic body 15 '. A strain gauge SG ′ is bonded to the inner peripheral surface 20a ′ of the circular hole 20 ′. Further, the opening such as the circular hole 20 ′ is configured to be sealed with the sealing material 24 ′ as in the first embodiment.
[0026]
Thus, even if the plate-like elastic body 15 ′ is rectangular, by adopting the above-described configuration, it is possible to detect the torque generated in the output shaft and to easily fix the flange to the flange as in the first embodiment. And has a sufficient sealing function, so that a waterproof function can be provided.
[0027]
FIG. 6 shows the torque meter 40 of the second embodiment. The four circular holes 50 of the torque meter 40 are respectively drilled from the rotational drive machine side and the rotational drive structure side of the plate-like elastic body 45 and penetrate each other. It has a circular bottom 50a, and a strain gauge SG (SG11 to SG18) is bonded to the bottom 50a. By setting it as the said structure, a shear strain can be measured and the high torque especially high rigidity can be measured with a sufficient precision.
[0028]
In addition to the above embodiment, the torque meter of the present invention can have various forms depending on the torque to be detected, the type of the rotary drive machine, etc., and can be easily attached and sealed with the rotary drive machine. Any structure that is waterproof and can detect torque with high accuracy may be used.
[0029]
【The invention's effect】
As is apparent from the above description, according to the present invention, the 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, so that attachment is easy. In addition, the space loss during the axial mounting can be omitted. Moreover, since each opening part is made into the structure which can be easily sealed with sealing materials, such as diaphragms and covers, such as a metal and resin, a sealing process made into the sealing structure can be given and a waterproof function can be improved. Further, since the torque meter does not rotate, durability and measurement reliability can be improved.
[0030]
Therefore, by measuring the strain with the strain gauge, the driving torque generated in the output shaft can be detected with high accuracy in any measurement environment. Therefore, it becomes possible to measure torque in a field that could not be applied so far, and it is possible to realize stable operation and improved product quality through torque monitoring.
[0031]
In addition, since the strain in various directions can be measured by appropriately setting the shape of the circular hole and the bonding position of the strain gauge according to the torque to be measured, depending on the torque to be detected such as low torque and high torque. The versatility of the torque meter can be enhanced.
[Brief description of the drawings]
FIG. 1 is a diagram showing an attachment state of a torque meter, a rotary drive machine, and a rotary drive structure according to a first embodiment of the present invention.
FIG. 2 is a perspective view of a plate-like elastic body of the torque meter according to the first embodiment.
FIGS. 3A and 3B are a front view and a side view of the torque meter according to the first embodiment, respectively, as viewed from the direction of the arrows.
FIG. 4 is a diagram showing a Wheatstone bridge circuit of the torque meter according to the first embodiment.
5A and 5B are diagrams showing a modification of the first embodiment. FIG.
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]
DESCRIPTION OF SYMBOLS 10 Torque meter 11 Flange fixing | fixed part 12 Base fixing | fixed part 13 Rotation drive structure 14 Rotation drive machine 14A Output shaft 14B Flange 15 Plate-like elastic body 16 Center through-hole 17, 18 Bolt hole 19 Torque transmission part 20 Circular hole 21 For lead wires Through hole 22 Annular groove 23 Cable outlet 24 Sealing material 30 Wheatstone bridge circuit SG Strain gauge B Bolt

Claims (4)

A torque meter that detects a drive torque generated on an output shaft of a rotary drive machine that drives a rotary drive structure by a rotary drive force;
A plate-like elastic body that is mounted between a flange provided in the rotary drive and the rotary drive structure and has a central through hole through which an output shaft of the rotary drive passes in the center,
A flange fixing portion provided around the center through hole and having fastening means with the flange ;
A base over scan fixing portion is a portion that does not rotate is fastened in a fixed base and concluded means above Symbol rotary drive structure by a rotational driving force of said rotary drive unit with which we provided outside of the flange fixing unit,
A torque transmitting portion in which the flange fixing portion and the base fixing portion are coupled ;
It has a plurality of circular holes drilled in the torque transmission part ,
Each of the circular hole, the lead wire through hole, and the annular groove is formed by connecting a plurality of lead wire through holes through which the lead wire is routed through the circular hole and the central through hole. The opening is sealed with a sealing material, and a strain gauge connected to the lead wire is bonded to the inner surface of the circular hole. The strain due to the torque acting on the torque transmitting portion is measured, and the drive torque generated on the output shaft is A torque meter characterized in that it is configured to be detected.   2. The torque meter according to claim 1, wherein the circular hole passes through a 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. .   The circular hole is respectively drilled from the rotary drive side and the rotary drive structure side of the plate-like elastic body, has a circular bottom surface that does not penetrate each other, and a strain gauge is bonded to the bottom surface. Torque meter as described.   The torque meter according to any one of claims 1 to 3, wherein the torque transmission part is disposed at a symmetrical position with respect to a center position of the central through hole.

Images