JP2021092430A - Encoder, fixing method of encoder cable, and robot - Google Patents

Abstract

To provide an encoder for suppressing movement of a wire, a method for fixing an encoder cable, and a robot.SOLUTION: An encoder 11 includes: a board 13 for mounting a light source 16 of an optical encoder or an optical sensor 15; a wire 130 connected with the board 13; a case 110 having a projection 111 extended in a direction along a Y axis; and a plate 121 having an opening 121a in which a length in a direction along a Z axis crossing a direction along the Y axis is longer than a length in a direction along the Z axis of the projection 111, and the wire 130 is disposed along the Z axis and is sandwiched while abutting on the projection 111 and a sidewall 121 of the opening 121a.SELECTED DRAWING: Figure 3

Description

The present invention relates to an encoder, a method for fixing an encoder cable, and a robot.

Conventionally, an encoder having a spindle gear and a plurality of sub-shaft gears and mounted on a robot or the like has been known. In such an encoder, the phase of the spindle gear connected to the rotating shaft of the drive motor and the phase of each of the plurality of sub-shaft gears are detected. The rotation angle of the spindle gear is calculated based on this detection result.

For example, Patent Document 1 proposes a structure in which a cable is fixed between a fixed body and a flat surface at a side portion of an encoder case in order to lock a cable connected to a rotation angle detection mechanism which is an encoder. There is.

Japanese Unexamined Patent Publication No. 2004-163336

However, in the cable fixing structure described in Patent Document 1, when a force is applied to the cable, the cable is easily displaced with respect to the fixed body, and the force is applied to the circuit board of the encoder connected to the cable, so that the light source of the encoder or the light source of the encoder There was a possibility that the position of the light receiving part would shift and the accuracy would decrease.

The encoder includes a substrate on which a light source or a light receiving portion of an optical encoder is mounted, wiring connected to the substrate, a case having a convex portion extending in the first direction, and a second direction intersecting the first direction. The wiring includes a plate having a recess having a length of the convex portion longer than the length of the convex portion in the second direction, and the wiring is arranged along the second direction, and the convex portion and the side wall of the concave portion are provided. It is sandwiched in contact with.

The encoder includes a substrate on which a light source or a light receiving portion of an optical encoder is mounted, wiring connected to the substrate, a case having a recess extending in the first direction, and a second direction intersecting the first direction. A plate having a convex portion having a length longer than the length of the concave portion in the second direction is provided, and the wiring is arranged along the second direction, and the side wall of the concave portion and the convex portion. It is sandwiched in contact with.

The robot includes the above encoder.

The method of fixing the encoder cable is as follows: a substrate on which a light source or a light receiving portion of an optical encoder is mounted, a case having a convex portion extending in the first direction on a side surface, and a case connected to the substrate and intersecting the first direction. In an encoder comprising a wiring arranged along a second direction and a plate having a recess in which the length of the second direction is longer than the length of the convex portion in the second direction, the wiring is provided. By sandwiching it between the convex portion and the side wall of the concave portion, it is raised from the side surface, lowered from the top portion via the top portion of the convex portion, and bent so as to follow the shape of the convex portion.

The schematic diagram which shows the structure of the robot which concerns on 1st Embodiment. The perspective view which shows the schematic structure of the motor mounted on the drive part. Sectional drawing which shows the structure of an encoder. The plan view which shows the structure of an encoder. An enlarged cross-sectional view showing a fixed state of wiring. The perspective view which shows the assembly method of an encoder. The perspective view which shows the assembly method of an encoder. The perspective view which shows the assembly method of an encoder. The perspective view which shows the assembly method of an encoder. The perspective view which shows the assembly method of an encoder. The perspective view which shows the appearance of the encoder which concerns on 2nd Embodiment.

In each of the following figures, the XYZ axes are attached as coordinate axes orthogonal to each other as necessary, the direction pointed by each arrow is the + direction, and the direction opposite to the + direction is the-direction. The plane including the X-axis and the Y-axis is horizontal, and the Z-axis is a vertical line extending in the direction in which gravity acts. The + Z direction may be upward, and the -Z direction may be downward. It should be noted that the terms "upper" and "lower" are merely names for explaining the relative positional relationship of each member, and do not limit the actual arrangement relationship and usage mode. Further, in each of the following figures, the scale of each member is different from the actual one for convenience of illustration.

1. 1. First Embodiment 1.1. Robot The configuration of the robot according to the first embodiment will be described with reference to FIG. In this embodiment, a SCARA robot (horizontal articulated robot) is illustrated as a robot. The robot of the present invention is not limited to the SCARA robot, and may be a vertical articulated robot other than the SCARA robot. Examples of the vertical articulated robot include a single-arm robot having one arm and a double-arm robot having two or more arms such as a double-arm robot.

As shown in FIG. 1, the robot 1 of the present embodiment includes a base 2, a movable portion 3, and a control device 4. Further, the robot 1 includes an encoder 11 (not shown), which is an example of the encoder of the present invention. Details of the encoder 11 will be described later.

The base 2 supports the movable portion 3. The base 2 is provided on a predetermined installation surface 100. The installation surface 100 is, for example, the floor surface of a room in which the robot 1 is allowed to perform work. The installation surface 100 is a surface such as a wall surface or ceiling surface in the room, an upper surface of a table on which the robot 1 is placed, a surface of a jig, and a surface of a table instead of the floor surface. May be good.

The movable portion 3 includes a first arm A1, a second arm A2, and a drive shaft portion S. The first arm A1 is rotatably supported around the first rotation shaft AX1 by the base 2. The first arm A1 can move in a direction parallel to the installation surface 100. Here, the rotation means a motion of rotating around the shaft, and the rotation includes the case where the rotation angle is less than 360 degrees and the case where the rotation angle is 360 degrees or more. Further, the rotation includes not only the motion of rotating in one direction but also the motion of rotating in both directions.

The first arm A1 is rotated around the first rotation shaft AX1 by the first drive unit M1 provided on the base 2. The first drive unit M1 is an actuator that rotates the first arm A1 around the first rotation shaft AX1. That is, in the present embodiment, the first rotation axis AX1 is a virtual axis that coincides with the rotation axis of the first drive unit M1.

The second arm A2 is rotatably supported around the second rotation shaft AX2 by the first arm A1. The second arm A2 can move in a direction parallel to the installation surface 100. The second arm A2 is rotated around the second rotation shaft AX2 by the second drive unit M2 provided on the second arm A2. In the present embodiment, the second rotation shaft AX2 is a virtual shaft that coincides with the rotation shaft of the second drive unit M2.

The second arm A2 includes a third drive unit M3 and a fourth drive unit M4, and supports the drive shaft unit S. The drive shaft portion S is supported by the second arm A2 so as to be rotatable around the third rotating shaft AX3 and to be translatable in the axial direction of the third rotating shaft AX3. In the present embodiment, the third rotation shaft AX3 is a virtual shaft that coincides with the central axis of the drive shaft portion S.

The drive shaft portion S is a cylindrical shaft body. A ball screw groove (not shown) and a spline groove (not shown) are provided on the outer peripheral surface of the drive shaft portion S, respectively. In the example shown in FIG. 1, the drive shaft portion S is arranged so as to penetrate the end portion of the second arm A2 opposite to the first arm A1.

An external device such as an end effector can be attached to the tip S1 of the drive shaft portion S. The tip S1 of the drive shaft portion S is one end in the axial direction of the two ends of the drive shaft portion S. The end effector referred to here is not particularly limited, but specifically refers to an end effector capable of holding an object by a finger portion. The end effector may be an end effector capable of holding an object by, for example, adsorption by air or magnetism. The end effector that can be attached to the tip S1 may be an end effector that does not hold an object. Holding an object here means making it possible to lift the object.

The third drive unit M3 rotates, for example, a ball screw nut provided on the outer peripheral portion of the ball screw groove of the drive shaft unit S via a timing belt or the like. As a result, the third drive unit M3 rotates the drive shaft unit S around the third rotation shaft AX3.

The fourth drive unit M4 rotates, for example, a ball spline nut provided on the outer peripheral portion of the spline groove of the drive shaft unit S via a timing belt or the like. As a result, the fourth drive unit M4 rotates the drive shaft unit S around the third rotation shaft AX3.

In the robot 1, the first drive unit M1 to the fourth drive unit M4 have the same configuration as each other. In the following description, the first drive unit M1 to the fourth drive unit M4 may be collectively referred to as the drive unit M, and the first rotation shaft AX1 to the third rotation shaft AX3 are collectively collectively referred to as the rotation shaft. Sometimes called AX. At least one of the drive units M includes a motor.

As described above, the robot 1 exemplifies the configuration including the first rotation shaft AX1 to the third rotation shaft AX3, but the number of configurations attached to the rotation shaft AX and the rotation shaft AX is limited to this. Not done.

1.2. The configuration of the encoder 11 provided in the encoder drive unit M will be described with reference to FIG. As shown in FIG. 2, the motor 10 of the present embodiment has a motor main body 9 which is a servo motor and an encoder 11 attached to an upper surface 9a which is an upper surface of the motor main body 9. The motor body 9 includes a shaft 5 extending along the Z axis. The center of the shaft 5 coincides with the center of the rotation shaft AX in the drive unit M. The configuration of the encoder 11 described below is an example, and the present invention is not limited to this.

The encoder 11 has a substantially rectangular parallelepiped appearance with the lower bottom surface omitted, and is fixed to the upper surface 9a of the motor body 9 via, for example, a screw member (not shown). The encoder 11 detects the rotation speed of a part of the shaft 5 protruding from the motor body 9 to the upper surface 9a.

The motor 10 is controlled by the control device 4 described above. The control device 4 is electrically connected to the motor body 9 and the encoder 11. The control device 4 calculates the rotation speed of the shaft 5 based on the information such as the detection result of the rotation speed of the shaft 5 in the motor body 9 transmitted from the encoder 11. Based on the rotation speed, the control device 4 controls the drive of the motor body 9 in the motor 10.

The configurations of the motor 10 and the encoder 11 will be described with reference to FIGS. 3 and 4. FIG. 3 is a cross-sectional view of the encoder 11 including the rotation axis AX along the XZ plane. FIG. 4 shows the planar arrangement relationship of each member in the encoder 11 in a state of being viewed from below to above. Note that, in FIGS. 3 and 4, for convenience of illustration, illustration of members not related to the description is omitted.

As shown in FIGS. 3 and 4, the encoder 11 includes a base portion 20, a spindle gear 21, a plurality of sub-shaft gears 22, 23, 24, a plurality of magnets 32, 33, 34, and a plurality of bearings 42, 43, 44. , And a shaft bearing 45. Further, the encoder 11 is an optical encoder and includes a light source 16, an optical sensor 15 as a light receiving unit, an encoder wheel 14, a substrate 13 which is an optical sensor substrate, wiring 130, a case 110, and a plate 121. In the encoder 11, a member including the above configuration is housed in the case 110, and the shaft 5 of the motor body 9 projects from below to the inside and is incorporated.

The encoder 11 has a partially unitized structure. Specifically, in the encoder 11, the base portion 20, the plurality of sub-shaft gears 22, 23, 24, the plurality of magnets 32, 33, 34, and the plurality of bearings 42, 43, 44 are unitized.

The encoder 11 detects the rotation speed of the gears 21, 22, 23, 24 when the power is supplied again after the power supply is stopped, thereby increasing the rotation speed of the motor 10 and the rotation shaft AX of the drive unit M. It is possible to detect the absolute position of. That is, the encoder 11 is a so-called batteryless encoder.

The base portion 20 is arranged so as to be orthogonal to the rotation axis AX. The base portion 20 is a member that holds a shaft bearing 45, a magnetic detection substrate 12, a substrate 13, and the like in addition to the unitized members described above. As the forming material of the base portion 20, for example, a resin or a metal having rigidity sufficient to hold the member is adopted.

The spindle gear 21 is attached to the root portion 5a of the shaft 5 protruding from the upper surface 9a of the motor body 9. The sub-shaft gears 22, 23, and 24 mesh with the spindle gear 21. The number of teeth of the spindle gear 21 and the number of teeth of the sub-shaft gears 22, 23, and 24 are different from each other.

The magnets 32, 33, 34 are permanent magnets. The magnet 32 is provided with the sub-shaft gear 22, the magnet 33 is provided with the sub-shaft gear 23, and the magnet 34 is provided with the sub-shaft gear 24, respectively. As a result, the magnets 32, 33, and 34 rotate together with the corresponding sub-shaft gears 22, 23, 24, respectively.

Bearings 42, 43, 44 are provided on the base portion 20. The bearings 42, 43, 44 are annular members that rotatably hold the corresponding sub-shaft gears 22, 23, 24 with respect to the base portion 20. Specifically, the bearing 42 holds the sub-shaft gear 22, the bearing 43 holds the sub-shaft gear 23, and the bearing 44 holds the sub-shaft gear 24.

In the present embodiment, the sub-shaft gears 22, 23, and 24 have the same configuration except that the outer diameter differs depending on the number of teeth. The magnets 32, 33, 34 have a similar configuration. The magnets 32, 33, 34 may have different sizes depending on the corresponding sub-shaft gears 22, 23, 24. Further, the bearings 42, 43, 44 may also have different sizes depending on the corresponding sub-shaft gears 22, 23, 24.

The holding portion 25 of the base portion 20 has a first bearing holding portion 25a and a second bearing holding portion 25b. The first bearing holding portion 25a is provided above the holding portion 25. The first bearing holding portion 25a is a recess for holding the shaft bearing 45. The second bearing holding portion 25b is provided below the holding portion 25. The second bearing holding portion 25b is a recess for holding the bearings 42, 43, 44.

The first bearing holding portion 25a is provided with a through hole 25a1 for inserting the shaft 5 of the motor 10. The inner diameter of the through hole 25a1 is larger than the outer diameter of the shaft 5. The shaft bearing 45 is fitted above the through hole 25a1 and, in other words, is press-fitted and held. The shaft bearing 45 is provided so as to fill a gap generated between the inner surface of the through hole 25a1 and the outer surface of the shaft 5. The member that fills the gap formed between the inner surface of the through hole 25a1 and the outer surface of the shaft 5 is not limited to the shaft bearing 45, and may be, for example, an oil seal.

A part of the outer peripheral surface of the first bearing holding portion 25a also functions as a support member for supporting the magnetic detection substrate 12. The magnetic detection substrate 12 is fitted and fixed to, for example, the outer peripheral surface of the first bearing holding portion 25a. In the encoder 11, since the sub-shaft gears 22, 23, 24 and the magnetic detection board 12 are held by the base portion 20, they are less susceptible to tolerances and thermal expansion than when they are held by members other than the base portion 20. Become. As a result, the assembly accuracy of the encoder 11 is improved, and the detection accuracy of the magnetic detection board 12 is improved.

The magnetic detection board 12 includes a plurality of magnetic sensors 52, 53, 54. The magnetic sensor 52 detects a change in the magnetic field caused by the rotation of the sub-shaft gear 22 in the magnet 32. The magnetic detection substrate 12 detects the rotation angle of the sub-shaft gear 22 from the change in the magnetic field detected by the magnetic sensor 52.

The magnetic sensor 53 detects a change in the magnetic field caused by the rotation of the sub-shaft gear 23 in the magnet 33. The magnetic detection substrate 12 detects the rotation angle of the sub-shaft gear 23 from the change in the magnetic field detected by the magnetic sensor 53.

The magnetic sensor 54 detects a change in the magnetic field caused by the rotation of the sub-shaft gear 24 in the magnet 34. The magnetic detection substrate 12 detects the rotation angle of the sub-shaft gear 24 from the change in the magnetic field detected by the magnetic sensor 54.

The magnetic detection board 12 is electrically connected to the control device 4 described above. Although not particularly limited, the magnetic detection substrate 12 may be electrically connected to the substrate 13. Further, the magnetic detection board 12 may be electrically connected to the control device 4 via the wiring 130 electrically connected to the board 13. The magnetic detection substrate 12 transmits the rotation angles of the sub-shaft gears 22, 23, 24, which are the detection results of the magnetic sensors 52, 53, 54, to the control device 4.

As shown in FIG. 3, the peripheral wall portion 26 of the base portion 20 is a tubular portion connected to the outer edge portion of the holding portion 25. The holding portion 25 is located above the lower end surface 26a of the peripheral wall portion 26 and below the upper end surface 26b of the peripheral wall portion 26. That is, the holding portion 25 is recessed above the lower end surface 26a of the peripheral wall portion 26, and is recessed below the upper end surface 26b of the peripheral wall portion 26. The substrate 13 is attached to the upper end surface 26b of the peripheral wall portion 26 via a plurality of screw members 17.

When the encoder 11 is attached to the motor main body 9, the first space K1 surrounded by the substrate 13, the peripheral wall portion 26, the holding portion 25, and the shaft bearing 45, the peripheral wall portion 26, the holding portion 25, and the upper surface of the motor main body 9 A second space K2 surrounded by 9a is formed. That is, the first space K1 and the second space K2 are separated by at least the holding portion 25 of the base portion 20.

The first space K1 is a space in which the magnetic detection board 12 or the encoder wheel 14 is arranged. The second space K2 is a space in which the spindle gear 21 and the sub-shaft gears 22, 23, 24 are arranged. Since the first space K1 and the second space K2 are separated, for example, grease applied to the gears and foreign matter such as abrasion powder generated by the meshing of the spindle gear 21 and the sub-spindle gears 22, 23, 24 can be removed. It is fastened in the second space K2. Therefore, the foreign matter is less likely to adhere to the magnetic detection board 12 and the encoder wheel 14 arranged in the first space K1. As a result, deterioration of the detection accuracy of the magnetic detection substrate 12 and the light transmittance of the encoder wheel 14 is suppressed.

The optical sensor 15 is mounted on the substrate 13 downward. The optical sensor 15 is arranged so as to face the light source 16 with the encoder wheel 14 interposed therebetween. For the light source 16, for example, a light emitting diode is used. In the optical sensor 15, the light emitted from the light source 16 passes through the encoder wheel 14 and is incident. The encoder 11 is a rotary encoder, and the encoder wheel 14 is fixed to the upper end of the shaft 5 and rotates together with the shaft 5.

On the encoder wheel 14, scales or slits are arranged radially and regularly in a region irradiated with light from the light source 16. Therefore, when the encoder wheel 14 rotates, the transmittance of light transmitted through the encoder wheel 14 changes intermittently due to the scale and the slit. By detecting the change with the optical sensor 15, the rotation angle of the spindle gear 21 attached to the shaft 5 is calculated. The range of the rotation angle of the spindle gear 21 is 0 ° or more and less than 360 °.

Note that what is mounted on the substrate 13 is not limited to the optical sensor 15, but may be a light source 16. Further, a mirror that reflects the light emitted from the light source 16 may be provided, and the light source 16 and the optical sensor 15 may be mounted on the substrate 13.

Wiring 130, which is an encoder cable, is electrically connected to the substrate 13. The substrate 13 transmits the rotation angle of the spindle gear 21, which is the detection result of the optical sensor 15, to the control device 4 via the wiring 130.

The wiring 130 is a flat cable including a plurality of conductors. In this embodiment, FFC (Flexible Flat Cable) is used as the wiring 130. The wiring 130 is not limited to a flat cable, and may be a bundle of a plurality of single-wire insulated wires and arranged flatly. When bundling the insulated wires, a resin tape such as polyimide may be used.

The case 110 is a member that constitutes the outer housing of the encoder 11. A convex portion 111 is provided on the side surface in the + X direction of the outer surface of the case 110 of a substantially rectangular parallelepiped. The convex portion 111 is located in the middle of the direction along the Z axis, which is the height direction of the case 110, and is arranged so as to extend in the direction along the Y axis as the first direction. Plates 121 are attached to the side surfaces of the case 110 at intervals equal to or greater than the thickness of the wiring 130.

Examples of the material for forming the case 110 include metals such as aluminum alloys and resins. In this embodiment, an aluminum alloy is used as the forming material of the case 110 from the viewpoint of dealing with electromagnetic waves. When resin is used as the forming material of the case 110, electromagnetic wave shielding treatment or the like may be performed.

The substrate 13 is arranged in the case 110 toward the upper surface of the case 110. The wiring 130 is connected downward with respect to the end portion of the substrate 13 in the + X direction. The wiring 130 is routed downward in the case 110, bent in the + X direction along the edge 112a of the case 110 near the lower end of the case 110, and is pulled out from the lower end of the case 110 in the + X direction.

Then, the wiring 130 is bent upward along the edge portion 112b and is routed upward between the side surface of the case 110 in the + X direction and the plate 121. Next, the wiring 130 is exposed to the outer surface from the opening 121a of the plate 121 along the convex portion 111, and then is pulled out again above the case 110 through between the case 110 and the plate 121. The opening 121a provided in the plate 121 is an example of the recess of the present invention.

In this way, the wiring 130 is bent and routed in the case 110. Therefore, it is possible to suppress an excessive stress applied to the wiring 130 as compared with the case where the wiring 130 is connected upward to the substrate 13 and is directly pulled out above the case 110. As a result, stress is less likely to be applied to the substrate 13. The fixed state of the wiring 130 near the convex portion 111 will be described later.

The edges 112a and 112b guide and bend the wiring 130 inside the case 110. Therefore, the edges 112a and 112b have rounded corners to prevent damage to the wiring 130. Further, an edge portion 112c is provided at a corner in the + X direction above the case 110 from which the wiring 130 is pulled out. The edge portion 112c has rounded corners to prevent damage to the wiring 130, for example, when the wiring 130 is bent in the −X direction.

1.3. Fixed state of wiring The fixed state of wiring in the vicinity of the convex portion 111 will be described with reference to FIG. In FIG. 5, the vicinity of the convex portion 111 of the case 110 shown in FIG. 3 is enlarged and shown.

As shown in FIG. 5, the wiring 130 is arranged along the Z axis on the side surface of the case 110 in the + X direction. The direction along the Z axis is the second direction orthogonal to the direction along the Y axis as the first direction. Here, the first direction and the second direction are not limited to being orthogonal to each other. Specifically, for example, when the first direction is a direction along the Y axis, the second direction may be included in a plane along the YZ plane and intersect with the first direction.

The convex portion 111 and the opening portion 121a of the plate 121 are arranged so as to face each other in the direction along the X axis. In the direction along the Z axis, the length of the opening 121a is longer than the length of the convex portion 111. As a result, when viewed in a plan view from the + X direction, a gap is secured between the upper and lower parts of the convex portion 111 and the opening 121a. The wiring 130 is routed in the gap.

The wiring 130 is routed from below between the side surface of the case 110 in the + X direction and the plate 121. Then, it rises from the side surface in the + X direction along the convex portion 111, falls from the top portion of the convex portion 111, and is drawn again between the side surface of the case 110 and the plate 121. In this way, the wiring 130 bends along the shape of the convex portion 111 in the vicinity of the convex portion 111, and is exposed to the outer surface at the opening 121a of the plate 121.

The wiring 130 is sandwiched between the convex portion 111 and the side wall 122 of the opening 121a in the vicinity of the convex portion 111. That is, the wiring 130 is pressed and fixed to the convex portion 111 and the side wall 122. As a result, even if a stress such as a tensile force acts on the wiring 130 drawn out from the case 110, the wiring 130 is fixed in the vicinity of the convex portion 111, so that the stress is suppressed from reaching the substrate 13.

Examples of the material for forming the plate 121 include metals such as aluminum alloys and resins. In the present embodiment, an aluminum alloy is used as the forming material of the plate 121, and the opening 121a is provided by press working. In press working, when the opening 121a is formed, burrs may occur around the opening 121a. In this case, in order to prevent the wiring 130 from being damaged by the burrs, the plate 121 is attached to the case 110 with the burrs-generated surface facing the outside in the + X direction. Further, a method such as laser cutting may be adopted for manufacturing the plate 121 including the opening 121a.

Here, in the present embodiment, the recessed portion of the plate 121 is illustrated as the opening 121a, but the present invention is not limited to this. The recess of the present invention may be a recess that does not penetrate the plate 121. Even when the concave portion is a concave portion, the wiring 130 may be sandwiched and fixed between the side wall of the concave portion and the convex portion 111.

Further, in the present embodiment, the case 110 is provided with the convex portion 111, and the plate 121 is provided with the opening 121a as a concave portion, but the present invention is not limited to this. The case 110 may be provided with a concave portion, and the plate 121 may be provided with a convex portion.

1.4. Wiring Fixing Method Among the methods for assembling the encoder 11, the method for fixing the wiring 130, which is an encoder cable, will be described with reference to FIGS. 6 to 10. Note that FIG. 6 shows a state before assembling the case 110 to the encoder 11.

As shown in FIG. 6, in the stage before assembling the case 110 to the encoder 11, the wiring 130 is not fixed except for being connected to the substrate 13.

Next, as shown in FIG. 7, the motor body 9 is covered with the case 110 and assembled. As a result, the arrangement of the wiring 130 is restricted downward from the substrate 13. Although not shown, the case 110 is fixed to the motor body 9 with screws or the like.

On the side surface of the case 110 in the + X direction, a pair of protrusions 123 and 125 arranged so as to face each other with the wiring 130 interposed therebetween are provided along the Y axis. In the direction along the Y-axis, the distance between the pair of protrusions 123 and 125 is longer than the length of the protrusions 111. On the side surface of the case 110, the convex portion 111 is provided substantially in the vertical direction along the Z axis, and the pair of protruding portions 123 and 125 are provided above the convex portion 111.

The protrusions 123 and 125 have different planar sizes when viewed from the + X direction. In the present embodiment, when viewed in a plan view from the + X direction, the shapes of the protrusions 123 and 125 are substantially circular, and the protrusions 123 are larger than the protrusions 125, but the present invention is not limited to this.

A pair of groove portions 114 are provided on the side surface of the case 110 so as to sandwich the convex portion 111 and the pair of protrusions 123 and 125 in the direction along the Y axis. That is, in the direction along the Y axis, the distance between the pair of groove portions 114 is longer than the length of the convex portion 111. Further, the depth of the pair of groove portions 114 in the direction along the X axis is equal to or larger than the thickness of the wiring 130.

Next, as shown in FIG. 8, the wiring 130 is bent upward. At this time, the pair of protrusions 123 and 125 guide the wiring 130 to the pair of groove 114s, and the wiring 130 enters the groove 114 to position the wiring 130. As a result, the wiring 130 is steadily bent upward, and the encoder 11 can be easily assembled.

In the direction along the Y-axis, the length of the convex portion 111 is longer than the width of the wiring 130. Therefore, the wiring 130 is arranged without protruding from the convex portion 111. At this stage, the wiring 130 is arranged so as to be raised in the + X direction by the convex portion 111, but it does not have to be bent in a shape along the convex portion 111.

Next, as shown in FIG. 9, the plate 121 is arranged on the side surface of the case 110 in the + X direction. The flat shape of the plate 121 when viewed from the + X direction is substantially rectangular. The plate 121 is provided with a pair of through holes 124, 126 at positions corresponding to the pair of protrusions 123, 125. Each of the pair of through holes 124, 126 fits into each of the corresponding pair of protrusions 123, 125.

Specifically, the through hole 124 corresponds to the protrusion 123, and the through hole 126 corresponds to the protrusion 125. The through hole 124 and the through hole 126 have different sizes in a plan view from the + X direction, and have sizes and shapes corresponding to the corresponding protrusions 123 and 125, respectively. In the present embodiment, since the protrusion 123 is larger than the protrusion 125, the through hole 124 is larger than the through hole 126, and the protrusion 123 does not fit into the through hole 126. For example, when the cross section of the protrusions 123 and 125 along the YZ plane is circular and the through holes 124 and 126 are circular, the diameter of the protrusion 123 is larger than the diameter of the through hole 126, and the protrusion 126 has a protrusion. 123 does not fit. Therefore, it is possible to prevent the plate 121 from being assembled to the case 110 by making a mistake in the front and back and the direction. Therefore, for example, when one side of the plate 121 has burrs generated during processing, the assembling direction of the plate 121 can be regulated so that the burrs and the wiring 130 do not come into contact with each other.

The opening 121a is an opening whose planar size when viewed from the + X direction is larger than the size of the convex portion 111. Therefore, in the wiring 130, the region raised in the + X direction by the convex portion 111 is exposed from the opening 121a without being blocked by the plate 121. At this time, the wiring 130 is pressed in the −X direction by the side wall 122 (not shown) of the opening 121a, and is bent into a shape along the convex portion 111. As a result, the wiring 130 is pressed and fixed to the convex portion 111 and the side wall 122.

The wiring 130 raised in the + X direction by the convex portion 111 may repel due to elasticity when the plate 121 is arranged from the + X direction. In the present embodiment, the protrusions 123, 125 and the through holes 124, 126 facilitate assembly against repulsion and prevent misalignment.

Four screw holes 127 are provided at the four corners of the plate 121 in order to screw the plate 121 to the case 110 in the next step.

Next, as shown in FIG. 10, using the above-mentioned four screw holes 127, the four corners of the plate 121 are screwed to the case 110 with four screws 141. As a result, the plate 121 is attached to the case 110, and the wiring 130 is fixed. The number of screws 141 used for screwing the plate 121 is not limited to four, and may be six, for example, as long as the corresponding number of screw holes 127 are arranged. Further, in addition to screwing, for example, adhesion may be adopted for attaching the plate 121 to the case 110.

According to this embodiment, the following effects can be obtained.

The movement of the wiring 130 attached to the encoder 11 can be suppressed as compared with the conventional case. Specifically, the wiring 130 is fixed by being in contact with and sandwiched between the convex portion 111 of the case 110 and the side wall 122 of the opening 121a of the plate 121. Further, since the wiring 130 is arranged orthogonal to the convex portion 111 extending along the Y axis, the wiring 130 is firmly fixed to the stress acting in the direction along the X axis. As a result, even if a stress such as a tensile force acts on the wiring 130, the wiring 130 is prevented from slipping and moving. Since the movement of the wiring 130 is suppressed, the stress is less likely to be applied to the substrate 13. Therefore, the detection accuracy in the encoder 11 is improved. As described above, it is possible to provide the encoder 11 that suppresses the movement of the attached wiring 130 and the method of fixing the wiring 130.

The wiring 130 bends at a portion rising from the side surface of the case 110 in the + X direction along the convex portion 111, a portion along the top portion of the convex portion 111, and a portion falling from the top portion of the convex portion 111 and along the above side surface. doing. Since the wiring 130 is bent at a plurality of locations and sandwiched between the convex portion 111 and the side wall 122 of the opening 121a, the movement of the wiring 130 can be further suppressed.

Since the wiring 130 is an FFC, when the wiring 130 is sandwiched between the convex portion 111 and the side wall 122 of the opening 121a, the plurality of conductors included in the wiring 130 are prevented from overlapping with each other. As a result, the individual conductors of the wiring 130 are evenly sandwiched and fixed, and the movement of the wiring 130 can be further suppressed.

Since the wiring 130 is guided by the pair of protrusions 123 and 125, the wiring 130 can be easily arranged when assembling the encoder 11. Further, since the length of the convex portion 111 is longer than the width of the wiring 130 in the direction along the Y axis, all the wiring 130 can be sandwiched and fixed between the convex portion 111 and the opening 121a.

When the plate 121 is attached to the side surface of the case 110 in the + X direction, it is possible to prevent mistakes in assembling the front and back surfaces and directions of the plate 121. Further, by preventing mistakes in assembly, when the opening 121a of the plate 121 is formed by punching, the generated burrs can be arranged on the front side not in contact with the wiring 130 to prevent damage to the wiring 130 due to the burrs. it can.

Since the opening 121a has a plane size larger than that of the convex portion 111 when viewed from the + X direction, the wiring 130 can be arranged between the convex portion 111 and the opening 121a. Further, since the four corners of the plate 121 are screwed, the position of the plate 121 with respect to the case 110 is less likely to be displaced, and the wiring 130 can be steadily fixed.

Since the robot 1 includes the encoder 11, the movement of the wiring 130 is suppressed, the detection accuracy of the encoder 11 is maintained, and the performance can be stably exhibited.

2. Second Embodiment The encoder 211 according to the present embodiment will be described with reference to FIG. Similar to the encoder 11 of the first embodiment, the encoder 211 is mounted on a SCARA robot, a vertical articulated robot other than the SCARA robot, and the like. The encoder 211 has a different form of the wiring 130 from the encoder 11. Therefore, the same reference numerals are used for the same components as those in the first embodiment, and duplicate description will be omitted.

As shown in FIG. 11, the encoder 211 of the present embodiment includes wirings 231 and 233 which are a plurality of insulated wires. The encoder 211 is different from the encoder 11 of the first embodiment in which the FFC is used as the wiring 130. Note that FIG. 11 shows a state before the plate 121 is attached.

Wiring 231 and 233 are pulled out from the end in the + X direction below the case 110 and are routed upward. Although not shown, the wirings 231 and 233 bend along the convex portion 111 in the same manner as the wiring 130 when the plate 121 is attached to the case 110. Then, the wirings 231 and 233 are sandwiched and fixed in contact with the convex portion 111 and the side wall 122 in the opening 121a of the plate 121.

Wiring 231 and 233 are pulled upward from the end in the + X direction above the case 110. For electrical connection purposes, a connector 231a is provided at the end of the wiring 231 and a connector 233a is provided at the end of the wiring 233.

Wiring 231 and 233 may be distributed above the case 110 and routed in different directions. As an example, in FIG. 11, the wiring 231 is arranged in the + Y direction and the wiring 233 is arranged in the −Y direction. At this time, the wirings 231 and 233 are bent above the side surface in the + X direction of the case 110. Edge portions 112l and 112m are provided at the upper ends of the pair of groove portions 114. The edges 112l and 112m have rounded corners. Therefore, even if the wirings 231 and 233 are bent and come into contact with the edges 112l and 112m, damage to the wirings 231 and 233 can be avoided.

Further, although not shown, a guide groove for guiding the wirings 231 and 233 to be routed may be provided above the case 110 and the like.

According to this embodiment, the same effect as that of the first embodiment can be obtained.

1 ... Robot, 11,211 ... Encoder, 13 ... Substrate, 15 ... Optical sensor as light receiving part, 16 ... Light source, 110 ... Case, 111 ... Convex part, 121 ... Plate, 121a ... Opening as concave part, 122 ... Side walls, 123, 125 ... protrusions, 124, 126 ... through holes, 130, 231,233 ... wiring.

Claims (9)

The board on which the light source or light receiving part of the optical encoder is mounted,
The wiring connected to the board and
A case with a convex portion extending in the first direction and
A plate having a recess in which the length in the second direction intersecting the first direction is longer than the length in the second direction of the convex portion is provided.
The wiring is arranged along the second direction, and is an encoder sandwiched in contact with the convex portion and the side wall of the concave portion. The convex portion is provided on the side surface of the case.
The encoder according to claim 1, wherein the wiring rises from the side surface, passes through the top of the convex portion, falls from the top, and is bent along the shape of the convex portion. The encoder according to claim 1 or 2, wherein the wiring is a flat cable including a plurality of conductors. A pair of protrusions arranged so as to face each other with the wiring in the first direction are provided on the side surface of the case.
One of claims 1 to 3, wherein in the first direction, the distance between the pair of protrusions is longer than the length of the convex portion, and the length of the convex portion is longer than the width of the wiring. Encoder described in. The plate is provided with a pair of through holes at positions corresponding to the pair of protrusions.
The pair of protrusions have different planar sizes and are different from each other.
The encoder according to claim 4, wherein each of the pair of through holes is fitted with each of the corresponding pair of protrusions. The plate is substantially rectangular in plane and
The concave portion is an opening having a planar size larger than that of the convex portion.
The encoder according to any one of claims 1 to 5, wherein the four corners of the plate are screwed to the case. The board on which the light source or light receiving part of the optical encoder is mounted,
The wiring connected to the board and
A case with a recess extending in the first direction and
A plate having a convex portion whose length in the second direction intersecting with the first direction is longer than the length in the second direction of the recess is provided.
The wiring is arranged along the second direction, and is an encoder sandwiched in contact with the side wall of the concave portion and the convex portion. A robot comprising the encoder according to any one of claims 1 to 7. The board on which the light source or light receiving part of the optical encoder is mounted,
A case having a convex portion extending in the first direction on the side surface,
Wiring connected to the substrate and arranged along the second direction intersecting the first direction,
In an encoder comprising a plate having a recess in which the length in the second direction is longer than the length in the second direction of the convex portion.
By sandwiching the wiring between the convex portion and the side wall of the concave portion, the wire is raised from the side surface, is lowered from the top portion via the top portion of the convex portion, and is bent along the shape of the convex portion. How to fix the encoder cable.

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