JP2016130730A - Motor system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor system which can detect the torque of a rotary output shaft of a motor continuously rotated with a simple structure, without requiring a complicated structure such as non-contacting transmission means when the transmission of power or a signal is carried out with a rotator.SOLUTION: A connection supporting portion 100 supporting a motor portion 5 and detecting torque have a first connecting portion 101c and a second connecting portion 101d having high stiffness and hardly deforming, while sandwiching a strain portion 101a detecting a distortion between them. The first connecting portion 101c is mechanically connected with a motor casing flange 5a of the motor portion 5, and the second connecting portion 101d is connected to a fixing member 7 for supporting the motor portion 5 and the connection supporting portion 100. Furthermore, the connection supporting portion 100 has a hollow portion, and a rotary output shaft 6 from the motor portion 5 penetrates the hollow portion to be connected to a load device 8a.SELECTED DRAWING: Figure 2

Description

  This application is a domestic priority claim application based on an application dated January 7, 2015. The present invention relates to a motor system having a torque detection function.

  Conventionally, it has been very difficult to measure the rotational torque of a motor. This is because when detecting various physical quantities of the rotating body, there is an obstacle in that it cannot be directly wired from a fixed side to a detector or circuit placed on the rotating body side. A known method for supplying electric power to a rotating body includes a slip ring mechanism. However, the slip ring mechanism needs to be precisely processed and assembled to maintain good mechanical contact between the brush and the slip ring over a long period of time. It was. In addition, leakage from the slip ring and brush is prevented, and the brush wears out, so it is necessary to periodically replace and maintain parts. Furthermore, since dust is generated during wear, suction and cleaning inside the casing are also necessary.

  On the other hand, rotary contactless power supply transformers have a separate transformer structure that forms a pair, and an AC conversion circuit is required to use electromagnetic induction, but contact failure occurs due to contactlessness. Insulation is easy, maintenance is not required, and the torque is measured by measuring the shear stress of the shaft with a strain gauge attached to the strain-generating part to detect the strain on a part of the load side shaft of the motor. Used in torque detectors to measure.

  On the other hand, the acquisition of rotational torque data is performed by converting an electrical signal into a light beam such as infrared rays and transmitting it from the rotating body side, and receiving it on the stationary side and returning it to the electrical signal. Therefore, such a torque detector requires a complicated configuration as described above in order to extract a physical quantity from the rotating body side, has a large number of parts, and is not easy to assemble. (Patent Document 1)

Japanese Patent No. 5543409 Japanese Patent No. 3324298

  On the other hand, Patent Document 2 is configured to obtain a torque value, which is a physical quantity, with a relatively simple structure. However, since the sensor unit is connected to the rotation output shaft, wiring processing such as a cable is necessary. There was a restriction on the rotation angle. In other words, if the rotation output shaft is about 2 to 3 rotations, it can be realized by devising the cable routing, but if it rotates more than this, the cable will be twisted, making it virtually impossible. Limited.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a motor system capable of detecting torque of a rotation output shaft of a continuously rotating motor with a very simple structure.

In order to achieve the above object, the motor system according to claim 1
A motor or a motor with a gear, a motor part having a rotation output shaft, and a connection support part that is mechanically connected to the motor part and supports the motor part;
With
The motor part and the connection support part are supported and fixed by a fixing member,
The rotary output shaft is connected to the load device,
The connection support is
A first connection portion connected and fixed to the motor casing of the motor portion;
A second connection portion connected and fixed to the fixing member;
A strain-generating portion that is between the first connection portion and the second connection portion and is deformed by twisting in the rotation direction around the axis of the rotation output shaft;
A strain detecting element provided in the strain generating portion to detect strain of the strain generating portion;
It is comprised.

In order to achieve the above object, the motor system according to claim 2
The second connection portion or the fixed member is provided with a bearing that rotatably supports the rotation output shaft.

In order to achieve the above object, the motor system according to claim 3
The strain generating part is cylindrical,
A strain gauge in which a strain detection element is attached to the cylindrical surface of the strain generating portion so as to face each other at 180 degrees about a cylindrical axis line;
The first connection portion and the second connection portion are formed in a flange joint shape.

In order to achieve the above object, the motor system according to claim 4 provides:
The strain generating part is composed of a plurality of flat beams.
Each flat beam is
It is connected to the second connection portion radially from the first connection portion, and has a point-symmetrical shape around the axis of the rotation output shaft,
A first plane perpendicular to the axis of the rotary output shaft;
A second plane parallel to the first plane;
Have
The strain detection element is composed of a strain gauge attached to each of the first plane and the second plane in pairs with each plate beam facing at 180 degrees about the axis of the rotation output shaft.

  According to the motor system of the first aspect of the present invention, it is possible to detect the torque of the rotation output shaft of a motor that continuously rotates with a simple structure without requiring a complicated configuration such as a non-contact transmission means. By this torque detection, it is possible to obtain the rotational torque value on the load side of the motor and to realize torque control of the motor, which has been difficult in the past.

  According to the motor system of the second aspect of the present invention, even when the length of the motor rotation output shaft to the load device is relatively long, the load device has a large rotational moment, and a radial load is generated, The influence on the strain generating part can be reduced.

  According to the motor system of the third aspect of the invention, there are advantages that the degree of freedom of the shape of the connection support portion is high and the versatility of incorporation into various devices is high because the connection portion has a flange joint shape.

According to the motor system of the fourth aspect of the present invention, the axial distance of the motor system can be made relatively small.

1 is an external perspective view of a motor system according to a first embodiment of the present invention. The partial cross-section structure perspective view of the motor system by the 1st Embodiment of this invention External view of a motor system according to a second embodiment of the present invention The partial cross-section structure perspective view of the motor system by the 2nd Embodiment of this invention Arrangement diagram of strain gauge of motor system according to first, second and fourth embodiments of the present invention Torque detection circuit diagram of the torque detector of the motor system according to the first, second and fourth embodiments of the present invention External appearance perspective view of a motor system according to a third embodiment of the present invention The partial cross-section structure perspective view of the motor system by the 3rd Embodiment of this invention The partial cross-section structure perspective view of the motor system by the 3rd Embodiment of this invention The torque detection circuit diagram of the torque detection part of the motor system by the 3rd Embodiment of this invention External view of a motor system according to a fourth embodiment of the present invention The partial cross-section structure perspective view of the motor system by the 4th Embodiment of this invention

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows the appearance of a motor system according to the first embodiment of the present invention. FIG. 2 shows some members of the motor system according to the first embodiment of the present invention parallel to the rotational axis direction. It is the cross-sectional structure perspective view cut | disconnected by the surface.

  A rotation angle detector 2 is attached to the opposite side of the motor 3 so that the rotation angle of the motor 3 can be detected. A motor cable 3a and a rotation angle detection unit cable 2a are respectively attached to the motor 3 and the rotation angle detection unit 2 for wiring. A reduction gear 4 which is mechanically connected and decelerates with a gear is attached to the load side of the motor 3 (see FIG. 2), and the rotation speed of the motor is reduced to a predetermined speed. Here, a combination of the rotation angle detection unit 2, the motor 3, and the speed reducer 4 is defined as a motor unit 5. Of course, a combination of only the rotation angle detector 2 and the motor 3 is also applicable in the present invention.

  The rotation output shaft 6 is a rotation shaft decelerated by the speed reducer 4, and is connected to the load device 8a to continuously rotate the load device 8a.

  The connection support portion 100 has a hollow portion, and has a first connection portion 101c and a second connection portion 101d with a thin strain generation portion 101a interposed therebetween, and is connected so as to cover the strain generation portion 101a. A support cover 103 is provided. The strain generating portion 101a has a cylindrical shape, and a strain gauge 102 (102a to 102h) is attached to the surface thereof, that is, a cylindrical surface as a strain detecting element capable of detecting strain. Details of the arrangement, connection, and circuit of the strain gauge 102 will be described later.

  The first connection portion 101c has a flange joint shape, and is connected and fixed by a bolt and a motor casing flange 5a which is a part of the motor portion 5 and does not rotate. The first connecting portion 101c has a shape that is thicker and more rigid than the strain generating portion 101a, and is a shape that is not easily deformed.

  The second connecting portion 101d also has a flange joint shape, and is connected and fixed by a fixing member 7 and a bolt. The second connecting portion 101d is also thicker and more rigid than the strain generating portion 101a, and has a shape that is not easily deformed.

  The fixing member 7 supports and fixes the motor unit 5 and the connection support unit 100 as a whole, and this is not easily deformed.

  In the first embodiment, a bearing 105 is provided between the rotation output shaft 6 and the load device 8a in order to cope with a relatively large load device 8a. The bearing holder 106 is fixed to the second connecting portion 101d by bolts, the bearing 105 is held by the bearing holder 106, and the bearing retainer 107 positions the outer ring of the bearing 105 and is fixed in the axial direction. Therefore, even when the length of the rotation output shaft 6 to the load device 8a is relatively long, the rotation moment of the load device 8a is large, and a radial load is generated, the influence on the strain generating portion 101a of the connection support portion 100 is reduced. it can. In the first embodiment, the bearing 105 is fixed to the second connecting portion 101d. However, the bearing 105 can be held by the fixing member 7.

  The strain gauge 102 is a shear type strain gauge, and the strain gauge 102a and the strain gauge 102b, and the strain gauge 102c and the strain gauge 102d are each provided integrally with a gauge tab having a 90-degree direction difference. Since the strain gauges 102e to 102h are hidden in FIG. 1 and cannot be illustrated, FIG. 5 shows the layout according to the arrow A and the corresponding strain gauges around the layout. That is, the strain gauge 102e and the strain gauge 102f are opposed to the strain gauge 102a and the strain gauge 102b at 180 degrees on the cylindrical surface of the strain generating portion 101a, respectively. Thus, the strain gauge 102g and the strain gauge 102h are opposed to each other at 180 degrees on the cylindrical surface of the strain generating portion 101a. As a result, twist in the rotation direction can be detected, and torque of the rotation output shaft 6 can be detected.

  FIG. 6 is a Wheatstone bridge circuit diagram of the torque detection circuit of the torque detection unit including the strain gauge 102 according to the first embodiment of the present invention. Corresponding to the 180 ° opposing positions in FIG. 5, for example, the strain gauge 102a and the strain gauge 102e are arranged at opposing positions in the circuit diagram. The strain gauge 102c and the strain gauge 102g, the strain gauge 102b and the strain gauge 102f, and the strain gauge 102d and the strain gauge 102h are also arranged to face each other in the same relationship. A signal from the strain gauge 102 can be taken out by the connection support cable 104, and a DC voltage to the Wheatstone bridge circuit is applied by the connection support cable 104.

  Wiring of each strain gauge 102 is performed by an electric wire, the strain gauge is patterned on a strip-like sheet using the technique of a flexible printed wiring board, and the wiring portion is also formed by pattern formation. It is also possible to wind the sheet and adhere it to the strain generating portion 101a. Although not shown, it is also possible to adopt a configuration in which a substrate on which a signal amplifying circuit for the strain gauge 102 is mounted is provided in the connection support portion cover 103 and signals are taken out by the connection support portion cable 104.

  FIG. 3 shows the appearance of the motor system according to the second embodiment of the present invention, and FIG. 4 shows some members of the motor system according to the second embodiment of the present invention parallel to the rotation axis direction. It is the cross-sectional structure perspective view cut | disconnected by the surface. Since the motor unit 5 is basically the same as that of the first embodiment, only the connection support unit 200 will be described.

  The connection support portion 200 has a hollow portion, and has a first connection portion 201c and a second connection portion 201d with a thin strain generation portion 201a interposed therebetween so as to cover the strain generation portion 201a. A connection support cover 203 is provided. The first connection portion 201c and the second connection portion 201d in the second embodiment are both hollow flange types, and the first connection portion 201c is connected and fixed to the motor casing flange 5a by bolts. The second connecting portion 201d is connected and fixed to the fixing member 7 with bolts. The strain generating portion 201a has a thin cylindrical shape, and a strain gauge 202 (202a to 202h) is attached to the surface as a strain detecting element capable of detecting strain.

  The arrangement and wiring of the strain gauges 202 are the same as those in the first embodiment, and may be wired by electric wires. When a strip-shaped sheet on which each strain gauge is arranged is wound and bonded to the strain generating part 201a, the assembly is performed. Positioning is easy. Further, a configuration in which a substrate on which a signal amplifying circuit of the strain gauge 202 is mounted is provided in the connection support portion cover 203 and a signal is taken out by the connection support portion cable 204 is possible as in the first embodiment.

  In the second embodiment, a bearing that rotatably supports the rotation output shaft 6 is not shown, but it is arranged on the second connecting portion 201d or the fixing member 7 with the same configuration as in the first embodiment. Is easy.

  FIG. 7 shows the appearance of the motor system according to the third embodiment of the present invention. FIGS. 8 and 9 show some members of the motor system according to the third embodiment of the present invention in the direction of the rotation axis. FIG. 3 is a perspective view of a cross-sectional structure in which some parts are omitted by cutting along a plane parallel to the surface. Since the motor unit 5 is basically equivalent to the first and second embodiments, only the connection support unit 300 will be described.

  The connection support portion 300 has a hollow portion, and includes a first connection portion 301c and a second connection portion 301d with the strain-generating portion 301a and the strain-generating portion 301b interposed therebetween, and a second connection A connection support portion cover 303a and a connection support portion cover 303b are provided so as to cover the portion 301d, the strain generation portion 301a, and the strain generation portion 301b.

  The first connection portion 301c is annular and flat, and is connected and fixed to the motor casing flange 5a with bolts, and has a structure that is highly rigid and difficult to deform.

  The strain generating part 301a and the strain generating part 301b are a pair of beams out of a plurality of flat beams projecting radially from the outer peripheral surface of the first connection part 301c, and are points about the axis of the rotation output shaft 6 It has a symmetrical shape and has a plane perpendicular to the axis of the rotation output shaft 6, that is, a first plane and a second plane. Further, strain gauges 302 (302a to 302h) for shear detection are attached to both the planes.

  The second connecting portion 301d is formed so as to surround the strain-generating portion 301a and the strain-generating portion 301b from the outer periphery, is flat and is connected and fixed to the fixing member 7 with a bolt, and has high rigidity and easily deforms. It is a difficult structure.

  The strain gauges 302 (302a to 302h) are arranged as shown in FIGS. 8 and 9, and the strain gauge 302a and the strain gauge 302c, and the strain gauge 302b and the strain gauge 302d are cylindrical axes in order to detect rotational torque. Are placed so as to face each other at 180 degrees.

  In the third embodiment, since the axial distance of the connection support portion 300 is relatively small and the strain generating portion 301a may be deformed to bend in a direction such as the B direction, the first and second strains may be canceled out. A strain gauge is disposed on each of the first plane and the second plane. That is, the strain gauge 302a and the strain gauge 302e, the strain gauge 302b and the strain gauge 302f, the strain gauge 302c and the strain gauge 302g, and the strain gauge 302d and the strain gauge 302h are arranged on the front and back sides, respectively. Therefore, in order to detect the rotational torque, the strain gauge 302e and the strain gauge 302g, and the strain gauge 302f and the strain gauge 302h are placed so as to face each other at 180 degrees also in the second plane. The deformation that occurs when 301a bends in the B direction can be canceled.

  FIG. 10 is a Wheatstone bridge circuit diagram of the torque detection circuit of the torque detection unit including the strain gauge 302 in the third embodiment of the present invention. In FIG. 8 and FIG. 9, those that form a pair in the strain generating portion 301 a are also provided so as to face each other in the Wheatstone bridge circuit.

  Further, the connection support part cover 303a and the connection support part cover 303b cover the strain generating part 301a, the strain generating part 301b, and the strain gauge 302, and do not directly apply external force to the strain generating part 301a and the strain generating part 301b. With a simple structure, a wiring (not shown) is accommodated. In addition, a configuration in which a substrate on which a signal amplification circuit of the strain gauge 302 is mounted is provided in the connection support portion cover 303a and a signal is taken out by the connection support portion cable 304 is possible as in the first and second embodiments. .

  7 to 9, the first plane and the second plane on which the strain gauge 302 is provided are drawn the same as the flange surfaces of the first connection portion 301c and the second connection portion 301d, respectively. However, the axial dimension of the strain generating portion 301a and the strain generating portion 301b, that is, the distance between the first plane and the second plane is appropriately selected depending on the detected torque value.

  In the third embodiment, the bearing that rotatably supports the rotation output shaft 6 is not shown, but it is arranged on the second connecting portion 301d or the fixing member 7 with the same configuration as in the first embodiment. Is possible. Note that when the bearing is disposed in the second connection portion 301d, a space for arranging the bearing is provided with a structure in which the thickness of the second connection portion 301d is increased and projects to the fixing member 7 side.

  FIG. 11 shows the appearance of a motor system according to the fourth embodiment of the present invention with some members transparent, and FIG. 12 shows some members of the motor system according to the fourth embodiment of the present invention. FIG. 3 is a perspective view of a cross-sectional structure taken along a plane parallel to the rotation axis direction. Since the motor unit 5 is basically equivalent to the first and second embodiments, only the connection support unit 400 will be described.

  The connection support portion 400 has a drum shape with a hollow portion, and includes a first connection portion 401c and a second connection portion 401d with a thin strain-generating portion 401a interposed therebetween. The first connecting portion 401c and the second connecting portion 401d in the fourth embodiment are both hollow flange types, and the first connecting portion 401c is connected and fixed to the motor casing flange 5a by bolts. The second connecting portion 401d is connected and fixed to the fixing member 7 with bolts. The strain generating portion 201a has a thin cylindrical shape and is partially provided with a hole so as to have an appropriate degree of deformation. A strain gauge 402 (402a to 402h) is used as a strain detecting element for detecting strain on the cylindrical surface. Is attached.

  The arrangement of the strain gauge 402 is the same as in the first and second embodiments, and is shown in FIGS. The wiring from the strain gauge 402 is the same as in the first and second embodiments, and may be wired by an electric wire. Of course, when a strip-shaped sheet on which each strain gauge is arranged is wound and bonded to the strain generating portion 401a, assembly and positioning are facilitated. In addition, it is also possible to adopt a configuration in which a substrate on which a signal amplifying circuit of the strain gauge 402 is mounted is provided in a portion surrounded by the fixing member 7 and a signal is extracted by a connection support portion cable (not shown).

  In the fourth embodiment, the fixing member 7 is formed into a U shape, and the motor unit 5 and the connection support unit 400 are provided therein, and the rotation output shaft 6 is supported by a bearing 105 attached to the fixing member 7. . The bearing 105 is fixed to the fixing member 7 by a bearing holder 107. According to this configuration, even when the rotational moment of the load device 8a is large and a radial load is generated, the influence on the strain generating portion 401a of the connection support portion 400 can be reduced. In the first embodiment, the bearing 105 is fixed to the second connecting portion 101d. However, in the fourth embodiment, an example in which the bearing 105 is held by the fixing member 7 is shown.

  As mentioned above, although embodiment regarding this invention was described, this invention is not limited to said embodiment, A various deformation | transformation is possible.

In the present invention, the strain generating portion that detects strain is not attached to the rotation output shaft side of the motor unit, but is attached to the non-rotating casing side of the motor unit. Therefore, the torque of the motor is detected by detecting the reaction force generated on the motor unit casing side due to the torque generated by direct connection of the rotation output shaft to the load device by the strain generating part attached to the motor unit casing side. can do. The rotation output shaft from the motor part passes through the hollow part of the connection support part and is directly connected to the load device, and the strain generating part attached to the motor part side does not rotate. In a conventional method of detecting torque by connecting a rotation output shaft of a motor unit and providing a strain generating unit between the load unit and the load device, signal transmission from the rotating torque detection unit and transmission of electric power to the torque detection unit are performed. Since the supply is performed without contact, it is not easy to assemble a large number of parts. On the other hand, since the present invention does not include a torque detection unit at the rotating portion, it is easy to extract a signal from the torque detection unit, and non-contact signal transmission and power supply are not required. Therefore, it is possible to detect the torque of the rotation output shaft of the motor unit with an extremely simple structure.

  As an application example of the present invention, the present invention can be applied to a robot that performs welding, assembly, etc., a cargo handling device, and the like.

DESCRIPTION OF SYMBOLS 1 Motor system 2 Rotation angle detection part 2a Rotation angle detection part cable 3 Motor 3a Motor cable 4 Reduction gear 5 Motor part 5a Motor casing flange 6 Rotation output shaft 7 Fixed member 8a, 8b Load device

DESCRIPTION OF SYMBOLS 100 Connection support part 101a Strain part 101c 1st connection part 101d 2nd connection part 102,102a, 102b, 102c, 102d, 102e, 102f, 102g, 102h Strain gauge 103 Connection support part cover 104 Connection support part cable 105 Bearing 106 Bearing holder 107 Bearing retainer

200 connection support part 201a strain generating part 201c first connection part 201d second connection part 202, 202a, 202b, 202c, 202d, 202e, 202f, 202g, 202h strain gauge 203 connection support part cover 204 connection support part cable

300 Connection support part 301a, 301b Strain generation part 301c First connection part 301d Second connection part 302, 302a, 302b, 302c, 302d, 302e, 302f, 302g, 302h Strain gauge 303a, 303b Connection support part cover 304 Connection Support cable 305 First plane 306 Second plane

400 connection support part 401a strain generating part 401c first connection part 401d second connection part 402, 402a, 402b, 402c, 402d, 402e, 402f, 402g, 402h strain gauge

Claims (4)

A motor or a geared motor, a motor part having a rotation output shaft, and a connection support part that is mechanically connected to the motor part and supports the motor part;
With
The motor part and the connection support part are supported and fixed by a fixing member,
The rotary output shaft is connected to a load device;
The connection support part is
A first connecting portion connected and fixed to a motor casing of the motor portion;
A second connection portion connected and fixed to the fixing member;
A strain generating portion that is between the first connection portion and the second connection portion and is deformed by twisting in a rotation direction around the axis of the rotation output shaft;
A strain detecting element provided in the strain generating portion in order to detect strain of the strain generating portion;
A motor system comprising:   The motor system according to claim 1, wherein a bearing that rotatably supports the rotation output shaft is provided in the second connection portion or the fixing member. The strain generating portion is cylindrical,
A strain gauge in which the strain detecting element is attached to the cylindrical surface of the strain generating portion so as to face each other at 180 degrees around a cylindrical axis;
The motor system according to claim 1, wherein the first connection portion and the second connection portion have a flange joint shape. The strain generating portion is composed of a plurality of flat beams,
Each plate beam is
The first connection portion is radially connected to the second connection portion, and has a point-symmetric shape about the axis of the rotation output shaft,
A first plane perpendicular to the axis of the rotary output shaft;
A second plane parallel to the first plane;
Have
The strain detection element is a strain gauge that is attached to each of the first plane and the second plane in pairs with the flat beams facing each other at 180 degrees about the axis of the rotation output shaft. The motor system according to claim 1 or 2, wherein