JP2009162542A - Encoder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an encoder which can be configured simply and can be miniaturized easily. <P>SOLUTION: The encoder 10 provided with a rotating pattern part 21 having a detecting pattern and being fixed to a rotatable part 13 of a base apparatus 11, and a detector 25 for detecting the detecting pattern, has an external cover 23 which covers the pattern part 21 and the detector 25 and can be fixed to a rotatable part 15 of the base apparatus 11. Boards 27a, 27b provided with a circuit for processing a signal detected by the detector 25, are fixed to the external cover 23 directly or indirectly, and the detector 25 is fixed to the boards 27a, 27b. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an encoder that is mounted on a base device and detects relative rotation between a rotating portion and a non-rotating portion of the base device.

  Conventionally, many encoders are known that are mounted on a base device such as a motor and detect relative rotation between a rotating portion and a non-rotating portion of the base device.

  For example, in Patent Document 1 below, a base member to which one of a light emitting element and a light receiving element is attached, a support member to which the other is attached, and a light emitting element and a light receiving element are operated with a rotating plate having a light transmission pattern interposed therebetween. A circuit for processing the detected signal, a circuit for processing the detected signal, and the like, and a plurality of substrates provided on each of the base member and the support member, with a specific structure between the base member and the support member It is configured to be electrically connected. In this encoder, the rotation angle can be detected by detecting the light transmission pattern of the rotating plate that rotates following the rotation of the base device by the light emitting element and the light receiving element.

  In order to attach this encoder to a base device such as a motor, a base member to which one of a light emitting element and a light receiving element and a substrate are fixed is attached to a casing which is a non-rotating part of the base device, and a rotating plate is attached to a motor shaft or the like. A support member on which the other of the light emitting element and the light receiving element and the substrate are fixed is attached to the base member, and various positioning such as positioning between the detection part and the rotating plate is performed with high accuracy. It is installed with.

In such an encoder, when dust or the like adheres to the substrate, the detection unit, or the rotating plate, moisture or the like adheres, it becomes impossible to perform a normal rotation amount detection operation. For this reason, the entire outer surface of the base member and the support member is covered with the outer cover that can be fixed to the base member and the support member and the outer cover that can be attached to the base device so as not to be exposed to the outside. The rotation amount detection operation can be maintained for a long time.
JP 2003-315103 A

  However, in the conventional encoder, since the exterior cover is disposed outside the base member and the support member, the outer shape of the encoder tends to be increased accordingly. In particular, in order to reduce the size of the encoder for mounting on a small base device, a space for mounting the exterior cover is required, and the base device, base member, support member, substrate, etc. are downsized. Therefore, it is necessary to provide a fixing means and a mounting part for mounting the exterior cover, and the configuration tends to be complicated, and it is not easy to downsize the encoder. ,

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an encoder that can be easily configured and easily reduced in size.

  In order to solve the above-described problems, an encoder according to the present invention has a detection pattern and includes a rotation code unit attached to a rotation unit of a base device, and a detection unit capable of detecting the detection pattern. The substrate having a circuit that covers the rotation sign portion and the detection portion, and includes an exterior cover that can be fixed to a non-rotation portion of the base device, and that processes a signal detected by the detection portion. It is directly or indirectly fixed to an exterior cover, and the detection unit is fixed to the substrate.

  According to the encoder of the present invention, the substrate including the outer cover that covers the rotation code portion and the detection portion and that can be fixed to the non-rotation portion of the base device, and that includes the circuit that processes the signal detected by the detection portion. Since the detection unit is fixed to the substrate while being fixed to the cover, the exterior cover that covers the rotation code unit and the detection unit can be used as a means for supporting the substrate and the detection unit. It is easy to make and easy to miniaturize.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  The encoder 10 of this embodiment is an optical modular encoder, and is mounted on various base devices, and the amount of rotation such as the relative rotation angle and the relative rotation speed between the rotating portion and the non-rotating portion of the base device is determined. It is to detect. Here, an example in which the rotation amount between the motor shaft 13 and the motor housing 15 is detected by being mounted on the motor 11 will be described.

  As shown in FIGS. 1 and 2, the encoder 10 has a detection pattern (not shown) and can be fixed to a rotation sign portion 21 that can be attached to the motor shaft 13 of the motor 11 and a motor housing 15 of the motor 11. Detection cover fixed to the divided substrate 27a so as to detect the amount of rotation such as the rotation angle and the number of rotations of the rotary sign portion 21 and the two divided substrates 27a and 27b fixed to the outer cover 23 Part 25.

  The rotation sign portion 21 is provided with a connection hole 29 for attaching to the motor shaft 13 on the motor housing 15 side (hereinafter referred to as the lower side). The motor shaft 13 is inserted into the connection hole 29, It is fixed by an appropriate method such as screwing, bonding, or fitting. On the surface opposite to the motor casing 15 of the rotation sign portion 21 (hereinafter referred to as the upper side), an optical detection pattern is provided in an annular shape with high accuracy around the rotation axis L of the rotation sign portion 21. Yes.

  The exterior cover 23 is a member for improving the appearance by covering the rotation sign portion 21 and the detection portion 25 and preventing entry of dust and water from the outside. The outer cover 23 may have a gap or an opening through which air can be vented. However, it is preferable that the outer cover 23 has a hermetic seal as high as possible except for the inevitable opening because it can improve the dustproof property and the waterproof property.

  2 and 3, the exterior cover 23 has an opening 31 on the upper side and closes the opening 31 with a cover main body 33 fixed to the motor housing 15 of the motor 11 on the lower side. And a lid 35.

  The cover main body 33 is integrally formed of a resin or the like in a substantially hollow rectangular tube shape along the rotation axis L of the rotation code portion 21, and an accommodation space 28 for accommodating the rotation code plate 21 and the divided substrates 27a and 27b is provided therein. Is provided. A fitting portion 33 a that can be fitted to a fitting convex portion 15 a formed on the motor housing 15 is formed at the lower end portion. In a state where the fitting convex portion 15a is fitted to the fitting portion 33a, the screw can be fixed to the motor housing 15 by screwing a screw (not shown) into the fitting convex portion 15a from the fixing hole 33b.

  The upper opening 31 of the cover body 33 is formed continuously from the entire upper end of the exterior cover 23 and a pair of opposing side portions, and the entire upper side is larger than the intermediate position between the pair of side portions. Opening is possible. Due to the large opening 31, projecting pieces 33 c are formed on the other pair of opposing sides of the cover body 33.

  The cover main body 33 is provided with two divided fixing portions 37a and 37b as substrate fixing portions for fixing the divided substrates 27a and 27b. The split fixing portions 37a and 37b are formed by projecting the inner wall of the cover main body 33 in a stepped manner on the pair of opposed side portions where the protruding pieces 33c are formed. The fixing portion 37a is disposed inside the upper divided fixing portion 37b. For this reason, when the plurality of divided substrates 27a and 27b are respectively fixed to the divided fixing portions 37a and 37b, the respective divided substrates 27a and 27b are arranged at positions where they are vertically overlapped.

  The split fixing portion 37a arranged closest to the motor housing 15 is provided so that the lower edge 31a of the opening 31 is positioned substantially on the side, and the operator splits and fixes the split substrate 27a. The position can be easily aligned and fixed to the portion 37a. Here, in the direction along the rotation axis L of the rotation sign portion 21, the split fixing portion 37 a is below the opening 31 even if the split fixing portion 37 a is at the same position as the lower edge portion 31 a of the opening 31. Although the position may be a position above the edge 31 a on the side, the divided fixing portion 37 a is slightly below the edge 31 a below the opening 31. This is because when the divided substrate 27a is placed on the divided fixing portion 37a, the divided substrate 27a is guided by the inner wall of the cover body 33 and can be easily placed.

  Each of the divided fixing portions 37a and 37b has a flat surface on which a surface of the divided substrates 27a and 27b on the rotation code portion 21 side can be placed. The flat surface is formed so that the surface on the rotation code portion 21 side of each divided substrate 27a, 27b is parallel to the surface of the rotation code portion 21 when the divided substrates 27a, 27b are placed.

  On the other hand, the lid body 35 of the exterior cover 23 is integrally formed of resin or the like in a substantially U-shaped cross section so as to correspond to the opening 31. The lid body 35 can be fixed to the cover body 33 by screwing a screw (not shown) from the fixing hole 33d of the protruding piece 33c of the cover body 33. By closing the opening 31 with the lid 35, the dustproof and waterproof properties of the accommodation space 28 can be secured.

  Although the detailed illustration of the divided substrates 27a and 27b is omitted, a processing circuit that processes a signal detected by the detection unit 25, an operation circuit of the detection unit 25, a processing circuit and an operation circuit, a control unit (not shown), and the like The printed circuit board includes various circuits such as a transmission circuit for transmitting various signals between them and various electronic devices.

  The detection unit 25 is fixed to the opposite surface of the divided substrate 27 a adjacent to the rotation code unit 21 that faces the rotation code unit 21. A transmission connector 39 is fixed to the upper side surface of the divided substrate 27b disposed on the uppermost side. A transmission cable 41 is connected to the transmission connector 39 through the through hole 35a of the lid 35 from the outside.

  A connection connector 43 as a connection member is fixed by soldering to the facing positions of the mutually facing surfaces of the divided substrates 27a and 27b, and connected to the circuits of the divided substrates 27a and 27b. The connection connector 43 can be connected by fixing the divided substrates 27a and 27b to the divided fixing portions 37a and 37b, respectively, and the adjacent divided substrates 27a and 27b are electrically connected by the connection connector 43. It is connected.

  As shown in FIG. 4, the detection unit 25 provided on the divided substrate 27a includes a light emitting unit 45 that irradiates light to the detection pattern of the rotation code unit 21, and a light receiving unit that receives the light reflected by the detection pattern. 47, and the light emitting unit 45 and the light receiving unit 47 are fixed to the same divided substrate 27a. In this detection unit 25, the light from the light emitting unit 45 is reflected by the detection pattern of the rotation code unit 21, and the reflected light is received by the light receiving unit 47 so that the rotation amount of the rotation code unit 21 can be detected. It is configured.

  Such divided substrates 27a and 27b are fixed by bonding with an adhesive while being placed on the flat surfaces of the divided fixing portions 37a and 37b, respectively. It is preferable that the adhesive for adhering the divided substrate 27a adjacent to the rotation sign portion 21 and the adhesive for adhering the other divided substrate 27b are different, and the adhesive for adhering the divided substrate 27b adheres the divided substrate 27a. It is preferable that the flexibility after curing or solidification is greater than that of the adhesive. This is because a slight positional deviation or the like generated between the divided substrate 27a and the divided substrate 27b can be absorbed by the adhesive having a large flexibility. For example, the value indicated by the rigidity is such that the latter becomes smaller between the adhesive that bonds the divided substrate 27a on which the detection unit 25 is provided and the adhesive that bonds the other divided substrate 27a. Is preferred.

  Specifically, as the adhesive that bonds the divided substrate 27b, for example, an adhesive made of a silicone resin or the like is preferable, and as the adhesive that bonds the divided substrate 27a, for example, a photocurable resin, An adhesive made of an epoxy resin or the like is preferable.

  In particular, the adhesive for fixing the divided substrate 27a is preferably made of a photocurable resin. Since the detection unit 25 is fixed to the divided substrate 27a, it is necessary to align and bond with accuracy during bonding. At that time, if it is a photo-curing resin, it is easy to move the divided substrate 27a after coating, and at the same time, if it is cured by irradiating light after alignment, it can be firmly fixed and maintain an accurately aligned arrangement. This is because it is easy to do.

  In this embodiment, a photocurable resin is used as an adhesive for bonding the divided substrate 27a to which the detection unit 25 is fixed, and a silicone resin is used as an adhesive for bonding the divided substrate 27b.

  Next, a method for mounting such an encoder 10 on the motor 11 will be described.

  In order to attach the encoder 10 to the motor 11, first, the rotation sign 21 is attached to the motor shaft 13. By connecting the motor shaft 13 to the connection hole 29 of the rotation code portion 21, the detection pattern of the rotation code portion 21 is arranged in an annular shape with high accuracy around the rotation axis L, so that the rotation code portion 21 is connected to the motor. Mounting is completed by fixing to the shaft 13.

  Next, the cover body 33 of the exterior cover 23 is attached to the motor housing 15. The fitting portion 33a of the cover main body 33 is fitted to the fitting convex portion 15a of the motor housing 15 and fixed by screwing with the fixing hole 33b, and the cover main body 33 is displaced with respect to the motor housing 15. Fix it to the extent that it does not.

  Next, as shown in FIG. 5, the divided substrate 27 a to which the detection unit 25 is fixed is inserted from the opening 31 and placed on the divided fixing unit 37 a closest to the rotation code unit 21 of the cover body 33. At that time, a photocurable adhesive is applied to a contact portion between the divided substrate 27a and the divided fixing portion 37a. In this state, using the waveform of the oscilloscope or the like, the position of the detection unit 25 is slightly moved on the division fixing unit 37a so as to be a position suitable for detection. Then, after the detection unit 25 is aligned at an appropriate position, the detection unit 25 is held at that position, and the portion to which the photocurable adhesive is applied is irradiated from the opening 31 to be cured, and the divided substrate 27a is divided and fixed. It fixes to the part 37a.

  At this time, the relative position in the height direction between the rotation code unit 21 and the detection unit 25 is set to an appropriate height by placing the divided substrate 27a on the divided fixing unit 37a.

  Next, another divided substrate 27b is inserted from the opening 31 and placed on the divided fixing portion 37b, and the connection connector 43 fixed to the divided substrates 27a and 27b is connected. In this state, an adhesive made of silicone resin is applied and fixed to a contact portion between the divided substrate 27b and the divided fixing portion 37b.

  Thereafter, the transmission cable 41 is passed through the through-hole 35a of the lid 35, and the tip thereof and the divided substrate 27b are connected by the transmission connector 39. Then, the opening 31 is closed by the lid 35, and the lid 35 Is attached to the cover body 33 by screwing with a fixing hole 33d. Thereby, all including the rotation code | cord | chord part 21, the division | segmentation board | substrates 27a and 27b, and the detection part 25 are covered with the exterior cover 23, and mounting | wearing is completed.

  According to the encoder 10 as described above, the divided substrate 27a, which covers the rotation code unit 21 and the detection unit 25, includes the exterior cover 23 that can be fixed to the motor housing 15 of the motor 11, and includes various circuits. 27b is fixed to the outer cover 23, and the detection unit 25 is fixed to the divided substrate 27a. Therefore, the outer cover 23 covering the rotation code unit 21 and the detection unit 25 is divided into the divided substrates 27a and 27b and the detection unit 25. Can be used as a means for supporting at a predetermined position. Therefore, it is not necessary to provide a structure for supporting the divided substrates 27a and 27b and the detection unit 25 separately from the exterior cover 23, and the structure can be simplified and easily downsized.

  In the encoder 10, the exterior cover 23 includes a cover main body 33 having an opening 31 and a lid 35 that closes the opening 31, and is divided and fixed for fixing the divided substrates 27 a and 27 b to the cover main body 33. Since the portions 37a and 37b are provided, the divided substrates 27a and 27b can be inserted from the opening 31 and fixed to the divided fixing portions 37a and 37b of the cover main body 33, and the exterior cover has dustproof and waterproof properties. It is easy to align and fix the divided substrates 27a and 27b even within the interior 23.

  Furthermore, in this encoder 10, the detection unit 25 includes a light emitting unit 45 and a light receiving unit 47, and these light emitting unit 45 and light receiving unit 47 are fixed to a surface facing the rotation code unit 21 of the divided substrate 27a. The detection unit 25 can be arranged on the upper side of the rotation code unit 21 and the encoder 10 can be easily downsized.

  Further, in the encoder 10, the divided fixing portion 37 a is configured to be placed on the surface facing the rotation code portion 21 of the divided substrate 27 a in parallel with the rotation code portion 21, and thus is placed on the division fixing portion 37 a. Even if the divided substrate 27a is moved along the divided fixing portion 37a, the relative distance between the detection unit 25 fixed to the divided substrate 27a and the rotation sign portion 21 can be kept constant. Therefore, when the divided substrate 27a is fixed to the divided fixing portion 37a, the alignment operation of the detection portion 25 is easy, and the detection portion 25 can be arranged with high accuracy with respect to the rotation code portion 21 to fix the divided substrate 27a. Easy.

  In particular, the opening 31 of the cover main body 33 is provided continuously to the upper end and the side, and the lower edge 31a is positioned substantially on the side of the divided fixing portion 37a. It is easy to open 31 widely from the upper side to the side of the divided fixing portion 37a. Therefore, when the divided substrate 27a to which the detection unit 25 is fixed is aligned and fixed to the divided fixing unit 37a, the alignment operation of the divided substrate 27a is easy.

  Furthermore, in this encoder 10, since the plurality of divided substrates 27a and 27b can be fixed to the plurality of divided fixing portions 37a and 37b so as to overlap vertically, the arrangement area in the lateral direction intersecting the rotation axis L is reduced. It is easy to downsize the encoder 10 in the lateral direction. Therefore, it is easy to cope with downsizing of the motor 11.

  By the way, in the encoder 10, the plurality of divided substrates 27 a and 27 b are bonded to different positions of the exterior cover 23. With such an arrangement, when the adhesive is cured or solidified, a stress caused by the shrinkage or expansion of the adhesive is applied to each of the divided substrates 27a and 27b. In use, stress due to thermal expansion and contraction of the divided substrates 27a and 27b and the outer cover 23 and stress received from the outside on the outer cover 23 are applied to the respective divided substrates 27a and 27b. For this reason, if a difference occurs in the stress applied to each of the divided substrates 27a and 27b, a minute shift tends to occur in the relative position between the plurality of divided substrates 27a and 27b. When the relative position shift occurs, stress may concentrate on the soldering portion for fixing the connector 43 for connecting the divided substrates 27a and 27b, and a crack may be generated in the soldering portion.

  However, in this encoder 10, the flexibility after curing or solidifying the adhesive that bonds the other divided substrate 27b is larger than the adhesive that bonds the divided substrate 27a to which the detection unit 25 is fixed. Due to the flexibility of the adhesive for adhering, the difference in stress applied to each of the divided substrates 27a and 27b can be absorbed. For this reason, it is difficult for stress to concentrate on the soldering portion for fixing the connection connector 43, and it is possible to make it difficult for the soldering portion to crack.

  Moreover, since the adhesive for bonding the divided substrate 27a to which the detection unit 25 is fixed is made of a photocurable resin, when the divided substrate 27a is fixed to the divided fixing portion 37a, it is placed on the divided fixing portions 37a and 37b. Thus, the divided substrate 27a can be easily aligned on the divided fixing portion 37a with the adhesive applied, and at the same time, it can be securely fixed firmly after the alignment. Therefore, it is easy to fix the divided substrate 27a.

  The above embodiment can be appropriately changed within the scope of the present invention. For example, in the above description, an example using two divided substrates 27a and 27b has been described. However, the detection unit 25 and various circuits are not limited. The present invention can be applied even when one provided substrate is used, and three or more divided substrates can also be used. Moreover, although the example which provided the two division | segmentation fixing | fixed part 37a, 37b as a board | substrate fixing | fixed part was demonstrated, similarly the number and shape can be changed suitably.

  Furthermore, in the above-described embodiment, the example in which the divided substrates 27a and 27b are directly fixed to the exterior cover 23 has been described. However, each of the divided substrates 27a and 27b is indirectly attached to the exterior cover 23 through other members. It is also possible to fix. For example, it is possible to attach a substrate fixing part or a split fixing part as a separate member to the inner side surface of the exterior cover 23 and fix the board or the split board to this.

  In the above description, the divided substrates 27a and 27b are all arranged parallel to the surface of the rotation code unit 21. However, the present invention is not particularly limited. For example, the detection unit 25 is fixed and is closest to the rotation code unit 21. It is also possible to arrange only the divided substrates 27a in parallel and arrange the other divided substrates 27b in different directions.

1 is a perspective view of an encoder according to an embodiment of the present invention. It is a partial perspective view which shows the encoder of embodiment of this invention and shows the AA cross section of FIG. It is a disassembled perspective view which shows the exterior cover of embodiment of this invention. It is a figure explaining the detection part of embodiment of this invention. It is a figure explaining the mounting procedure of the encoder of embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Encoder 11 Motor 13 Motor shaft 15 Motor housing | casing 21 Rotation code | cord | chord part 23 Exterior cover 25 Detection part 27a, 27b Divided board 31 Opening part 33 Cover main body 35 Cover body 37a, 37b Divided fixing part 43 Connector 45 Light emission part 47 Light reception Part

Claims (8)

An encoder having a detection pattern and having a rotation code portion attached to a rotation portion of a base device, and a detection portion capable of detecting the detection pattern,
Covering the rotation code part and the detection part, and equipped with an exterior cover that can be fixed to a non-rotation part of the base device,
An encoder characterized in that a substrate having a circuit for processing a signal detected by the detection unit is directly or indirectly fixed to the exterior cover, and the detection unit is fixed to the substrate.   The exterior cover has an opening and a cover body that is fixed to the base device, and a lid that closes the opening, and fixes the substrate inserted from the opening to the cover body. The encoder according to claim 1, further comprising a substrate fixing part.   The detection unit includes a light emitting unit that irradiates light to the rotation code unit and a light receiving unit that receives light reflected by the rotation code unit, and the light emitting unit and the light receiving unit include the rotation code of the substrate. The encoder according to claim 1, wherein the encoder is fixed to a surface facing the portion.   4. The encoder according to claim 2, wherein the substrate fixing portion is configured to be able to place the facing surface of the substrate parallel to the rotation code portion. 5.   The cover body is fixed to the base device on one side, and the opening is provided continuously to the other side end and side, and the edge on the one side of the opening formed in the side The encoder according to any one of claims 2 to 4, wherein the portion is located substantially on a side of the substrate fixing portion.   The substrate includes a plurality of divided substrates that are electrically connected to each other, and the substrate fixing portion includes a plurality of divided fixing portions that can fix the plurality of divided substrates to positions that overlap each other. The encoder according to claim 2, wherein the detection unit is fixed to the divided substrate adjacent to the unit. The plurality of divided substrates are connected via connection members soldered to the divided substrates,
The flexibility after hardening or solidification of the adhesive that adheres the other divided substrate is larger than that of the adhesive that adheres the divided substrate to which the detection unit is fixed. Encoder.   The encoder according to claim 7, wherein the adhesive that bonds the divided substrate to which the detection unit is fixed is made of a photocurable resin.

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