JP2018186605A - Motor with rotary transformer and method for manufacturing motor with rotary transformer - Google Patents

Abstract

A motor with a rotary transformer is provided that is less likely to be damaged.
A motor with a rotary transformer is attached to a motor MT including a rotor Mr, a stator Ms, and rotary transformers 30a and 30b, a base housing B including column portions 51a and 51b, and column portions 51a and 51b. Shaft support members (for example, collars) 91 and 93 that support the shaft S1 of the motor MT, and elastic members (for example, coil springs) 95 provided between the shaft support members 91 and 93 and the motor MT are provided.
[Selection] Figure 1

Description

  The present invention relates to a motor with a rotary transformer and a method for manufacturing a motor with a rotary transformer, and more particularly to a motor with a rotary transformer provided with a shaft support member that supports a shaft of the motor, and a method for manufacturing a motor with a rotary transformer.

  A motor with a rotary transformer in which a rotary transformer is provided in the motor is known (for example, see Patent Document 1 below). Furthermore, an apparatus including such a motor with a rotary transformer is known (for example, see Patent Document 2 below).

  Manufacture of a device having the configuration of Patent Document 2 is performed as follows. Referring to FIG. 13 of Patent Document 2, first, the drive shaft 31 of the drive motor 104 is inserted from the openings 74 of both support portions 56 and 57. Thereafter, the bearing collar 43 is inserted from the axial direction. At that time, the outer peripheral portion of the central cylindrical portion of the bearing collar 43 is inserted into the cylindrical portions 54 and 55 of the support columns 56 and 67 while the inner cylindrical portion of the bearing collar 43 is engaged and inserted into the drive shaft 31. The drive shaft 31 of the drive motor 104 is supported by the two column portions 56 and 57 of the base 4 via the bearing collar 43. The position of the drive rotor 3 can be shifted by moving the bearing collar 43 in the axial direction. Thereby, the positional relationship between the brush 39 and the slip ring 13 can be adjusted. When the position of the bearing collar 43 is determined, the base 4, the bearing collar 43, and the drive shaft 31 are quickly fixed with an adhesive.

JP, 2015-076978, A JP 2002-248103 A

  A case is assumed in which the motor with a rotary transformer described in Patent Document 1 is supported by two support columns via a bearing collar 43 described in Patent Document 2. When such a configuration is adopted, the bearing holder 12 formed by fitting the bearing 3A of the motor with the rotary transformer described in Patent Application 1 is pressed by the bearing collar 43 described in Patent Document 2, or the bearing 3B is By pressing the bearing holder 14 that is fitted, the position of the motor with the rotary transformer is shifted and adjusted. After the adjustment position is determined, the bearing collar 43 and the shaft S1 are fixed with an adhesive.

  However, as described above, when the bearing holder 12 is pressed by the bearing collar 43 or when the position of the motor with the rotary transformer is adjusted by pressing the bearing holder 14 and an excessive pressing force is applied, the bearing holder 12 and There is a possibility that the adhesive force between the shaft S1 or between the bearing holder 14 and the shaft S1 is reduced or the applied adhesive is peeled off.

  Further, when the adhesive force between the bearing holder 12 and the shaft S1 or between the bearing holder 14 and the shaft S1 is reduced or the applied adhesive is peeled off, the gap between the rotary transformers (primary side and secondary side) (The distance between the stationary body and the rotating body) is narrowed, and depending on the situation, the stationary body and the rotating body of the rotary transformer may come into contact with each other and be damaged.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a motor with a rotary transformer that is unlikely to be damaged and a method for manufacturing the motor with a rotary transformer.

  In order to achieve the above object, according to one aspect of the present invention, a motor with a rotary transformer is provided with a motor including a rotor, a stator, and a rotary transformer, a column portion, and the shaft portion of the motor. A shaft support member to be supported; and an elastic member provided between the shaft support member and the motor.

  Preferably, the elastic member is a coil spring.

  Preferably, the shaft support member and the support column are screwed together.

  Preferably, the rotor includes a magnet, the stator includes a coil, and the shaft support member and the shaft are bonded to each other.

  Preferably, the spring force of the elastic member is smaller than the adhesive strength between the bearing holder of the motor and the shaft, and the shaft support member is not bonded to the shaft support member. The spring force is such that the motor can be moved when the member presses the elastic member.

  According to another aspect of the present invention, a method for manufacturing a motor with a rotary transformer, in which a motor including a rotor, a stator, and a rotary transformer is fixed to a column part, is attached to the column part and supports a shaft of the motor. Engaging the shaft of the motor and the support through the shaft support member, disposing an elastic member between the shaft support member and the motor; and the shaft support member disposing the elastic member. And the step of moving the motor by pressing.

  Preferably, the shaft support member is fitted into the support column, and the shaft support member and the shaft are fitted with a clearance. The method of manufacturing a motor with a rotary transformer includes: a step of moving the motor; After the position adjustment in the axial direction, the method further includes the step of bonding the shaft support member and the shaft.

  According to still another aspect of the present invention, a motor with a rotary transformer includes a shaft, a bearing holder attached to the shaft, and a rotary transformer attached to the bearing holder. A groove into which a member can be inserted is formed.

  According to the present invention, it is possible to provide a motor with a rotary transformer that is less likely to be damaged and a method for manufacturing a motor with a rotary transformer.

It is sectional drawing of the motor with a rotary transformer in the 1st Embodiment of this invention. It is the elements on larger scale near the right end part of shaft S1 shown in FIG. It is a perspective view of the base housing B shown in FIG. It is the elements on larger scale which show the modification of right shaft part vicinity of the shaft S1 shown in FIG.

  FIG. 1 is a cross-sectional view of a motor with a rotary transformer according to a first embodiment of the present invention. FIG. 2 is a partially enlarged view of the vicinity of the right end portion of the shaft S1 shown in FIG. FIG. 3 is a perspective view of the base housing B shown in FIG.

  The apparatus using the motor with a rotary transformer in the present embodiment adjusts the position of the motor MT by moving the shaft support members 91 and 93 fitted to the support columns 51a and 51b of the base housing B. Hereinafter, each part of the apparatus will be described.

  As shown in FIGS. 1 and 2, the motor MT with a rotary transformer is an outer rotor type motor.

  The motor MT is a substantially cylindrical rotor case in which a stator Ms wound around an iron core fixed to a shaft S1 and an annular magnet m disposed on the inner peripheral side of the stator Ms. And a rotor Mr. In other words, the motor MT has a stator Ms having an iron core and windings in the center, and a rotor Mr composed of a magnet m and a rotor case in the outer peripheral direction of the stator Ms.

  In the motor MT, the shaft S1 is fixed to the column portions 51a and 51b of the base housing B, and the rotor Mr rotates around the stator Ms fixed to the shaft S1.

  A rotary transformer 30a (4a, 5a) integrated with a bearing is mounted on one end side (left side in FIG. 1) of the motor MT, and on the other end side (right side in FIG. 1) of the motor MT. A rotary transformer 30b (4b, 5b) integrated with the bearing is mounted.

  In the motor MT with a rotary transformer, the shaft S1 is fixed to the base housing B, and the rotor Mr rotates around the shaft S1. Therefore, the first rotary transformer 4a and the third rotary transformer 4b that are fitted and connected to the rotor case of the rotor Mr become the rotary transformer on the rotation side, and the second rotary transformer 5a that is connected and fixed to the shaft S1. The fourth rotary transformer 5b is a fixed-side rotary transformer.

  In the bearing-integrated rotary transformer 30a, the first bearing holder 11 is assembled to the outer ring of the bearing, and the second bearing holder 12 is assembled to the inner ring of the bearing.

  Then, the first rotary transformer 4 a is attached to the first bearing holder 11, and the second rotary transformer 5 a is attached to the second bearing holder 12.

  Similarly, in the bearing-integrated rotary transformer 30b, the third bearing holder 13 is assembled to the outer ring of the bearing, and the fourth bearing holder 14 is assembled to the inner ring of the bearing.

  Then, the third rotary transformer 4 b is mounted on the third bearing holder 13, and the fourth rotary transformer 5 b is mounted on the fourth bearing holder 14.

  With the above configuration, the first rotary transformer 4a and the second rotary transformer 5a, and the third rotary transformer 4b and the fourth rotary transformer 5b are assembled via the high-precision bearings of the common parts. The second rotary transformers 4a and 5a and the third and fourth rotary transformers 4b and 5b can be improved in dimensional accuracy.

  As shown in FIGS. 1-3, the base housing B consists of two support | pillar parts 51a and 51b and the connection part 53 which connects two support | pillar parts 51a and 51b.

  The base housing B is formed by kneading a stainless steel (SUS316L) as a metal powder and a thermoplastic resin serving as a binder, and using a metal powder injection molding method (MIM: Metal Injection Molding). Inclined portions 59a and 59b are formed on the base sides of the two support columns 51a and 51b, and are formed so that the thickness on the base side is larger than the thickness on the tip side of the support columns 51a and 51b. Thus, the strength of the column portions 51a and 51b is improved by increasing the thickness of the base side.

  As shown in FIG. 3, the connecting portion 53 of the base housing B is formed with a mounting portion 56a of the base housing B, and the mounting portion 56a is provided with a through hole 57b for screwing.

  In the manufacturing process of the motor with the rotary transformer, the motor MT is attached to the base housing B as follows.

  First, the shaft S1 of the motor MT with a rotary transformer is inserted from the openings 81a and 81b of both the column portions 51a and 51b, and thereafter, the inner diameter cylindrical portion of the shaft support members 91 and 93 is engaged and inserted into the shaft 1, and the shaft The outer peripheral portion of the central cylindrical portion of the support members 91 and 93 is fitted into the openings 81a and 81b of the support columns 51a and 51b. Accordingly, the shaft S1 is supported via the shaft support members 91 and 93.

  As the shaft support members (for example, collars) 91 and 93, for example, parts obtained by nickel-plating brass can be used, but there are no particular restrictions on materials in terms of structure.

  The shaft S <b> 1 is a clearance fit with respect to the inner cylindrical portions of the shaft support members 91 and 93. That is, the shaft S1 can move freely with respect to the shaft support members 91 and 93. This is to make the elastic member (for example, coil spring) 95 work effectively.

  The outer peripheral portion of the central cylindrical portion of the shaft support members 91 and 93 is press-fitted into the openings 81a and 81b of the support columns 51a and 51b. That is, the frictional force between the outer peripheral part of the central cylindrical part of the shaft support members 91 and 93 and the openings 81a and 81b of the column parts 51a and 51b is large. Accordingly, the shaft support members 91 and 93 cannot move with respect to the column portions 51a and 51b unless a certain amount of force is applied. By applying an external force greater than a predetermined value, the relative positions of the shaft support members 91 and 93 and the column portions 51a and 51b can be changed. In a state where no external force is applied, the shaft support members 91 and 93 and the column portions 51a and 51b are fixed by a frictional force.

  A relay amplifier board 73 is installed on the surface of the base housing B facing the motor MT, and an MR (magnetoresistive) element (Z phase) 71 is provided thereon. A Z-phase pin P is provided on the rotor Mr of the motor MT. The Z-phase pin P is a pin made of a magnetic material for detecting the reference position of the rotor Mr. An MR (magnetoresistive effect) element (Z phase) 71 detects the position of the Z phase pin P. The rotor Mr is provided with an encoder magnet 90.

  In order to adjust the positional relationship between the component parts of the motor MT such as the Z-phase pin P and the base housing B, the position adjustment of the motor MT with a rotary transformer is performed at the time of assembling the apparatus.

  By applying an external force to the shaft support members 91 and 93, it can be moved in the direction in which the shaft (shaft S1) extends. Thereby, the position of the motor MT can be shifted. Specifically, the right shaft support member 93 in FIG. 1 is moved leftward in the axis (shaft S1), and the elastic member 95 housed in the bearing holder 14 on the outer periphery side of the shaft S1 is pressed. The position of the motor MT with a rotary transformer moves to the left in the axial direction via the elastic member 95.

  Even when an excessive pressing force is applied when the motor MT is moved and adjusted in this way, the excessive pressing force can be absorbed by the elastic member 95. As a result, it is possible to prevent a decrease in the adhesive force between the bearing holders 12 and 14 and the shaft S1 and a problem that the applied adhesive is peeled off. Further, the gap between the rotary transformers 4a and 5a and the gap between the rotary transformers 4b and 5b are narrowed, and they can be prevented from contacting each other.

  Whether the motor MT (shaft S1) moves when the elastic member 95 is pushed by the right shaft support member 93 in FIG. 1 depends on the state of the left shaft support member 91 and the left bearing holder 12.

  In a state where the right shaft support member 93 is in contact with the elastic member 95, when the shaft support member 93 is further moved to the left with respect to the base housing B, the space between the left shaft support member 91 and the end face of the bearing holder 12 is between If there is a clearance, the motor MT and the shaft support member 93 (together with the elastic member 95) move to the left together, so that the shaft S1 integrated with the motor MT also moves to the left together.

  When the right shaft support member 93 is in contact with the elastic member 95 and the shaft support member 93 is further moved to the left with respect to the base housing B, the left shaft support member 91 and the end surface of the bearing holder 12 come into contact with each other. If so, only the shaft support member 93 moves, and the motor MT (shaft S1) does not move. At this time, the relative distance between the right shaft support member 93 and the bearing holder 14 of the motor MT is shortened, and the elastic member 95 is contracted.

  When the shaft support member 93 is moved in the axial direction and the position of the motor MT with a rotary transformer is determined, the column portions 51a and 51b, the shaft support members 91 and 93, and the shaft S1 are quickly fixed with an adhesive.

  The position adjustment of the motor MT with a rotary transformer will be described in more detail.

  Regarding the friction between the inner diameter and the outer diameter of the shaft support members 91 and 93, the outer diameter is press-fitted, so that the friction between the outer diameter and the column portions 51a and 51b (that is, the outer diameter and the openings 81a and 81b) is large. Become. On the other hand, since the inner diameter sides of the shaft support members 91 and 93 are engaged with the shaft S1 by clearance fitting, the friction between the inner diameter and the shaft S1 is small.

  Therefore, when the shaft support members 91 and 93 are moved in the axial direction against the friction between the outer diameter and the column portions 51a and 51b (that is, the outer diameter and the openings 81a and 81b) (the openings of the column portions 51a and 51b). When the press-fitting positions with 81a and 81b are changed), the positional relationship between the shaft support members 91 and 93 and the openings 81a and 81b of the support columns 51a and 51b changes. At this time, if the motor MT is in a position where it cannot move, the positional relationship between the shaft support members 91 and 93 and the shaft (shaft) S1 also changes. This is because the shaft support members 91 and 93 and the shaft (shaft) S1 are loosely fitted, so that they are relatively movable.

  The assembly of the apparatus including the motor MT with the rotary transformer is performed in the following procedure.

  (Step 1) The shaft S1 of the motor MT is inserted into the openings 81a and 81b of the support columns 51a and 51b of the base housing B from the openings 81a and 81b. At this time, the shaft S1 and the openings 81a and 81b are in a loose state because the shaft support members 91 and 93 are not provided.

  (Step 2) The shaft support member 91 on the left side in FIG. 1 is press-fitted into the opening 81a of the support column 51a of the base housing B. The press-fitting position is a position where the left end surface of the shaft support member 91 and the left end of the base housing B are brought into surface contact. At this time, since there is no shaft support member 93 on the right side, the motor MT has a backlash in the axial direction, and no axial pressure is applied to the motor MT.

  (Step 3) An elastic member 95 is inserted into a circular (cylindrical) groove provided outside (outside) the bearing holder 14 on the right side of FIG.

  (Step 4) The shaft support member 93 on the right side of FIG. 1 is press-fitted into the opening 81b of the support column 51b of the base housing B. The press-fitting position is up to a position where the right end surface of the shaft support member 93 and the right end of the base housing B are flush with each other. At this position, the elastic member 95 is set so as not to be crushed (the spring force is in effect).

  (Step 5) The motor MT is positioned with respect to the base housing B. Initially, the outer diameters of the shaft support members 91 and 93 and the base housing B are press-fitted. On the other hand, a clearance fit is inserted between the inner diameters of the shaft support members 91 and 93 and the shaft S1.

  When the right shaft support member 93 in FIG. 1 is in contact with the elastic member 95, when the shaft support member 93 is further press-fitted (moved), the shaft support member 93 pushes the motor MT to the left via the elastic member 95. When the right end surface of the left shaft support member 91 and the left end surface of the bearing holder 12 of the left rotary lance 30a come into contact with each other, the motor MT is positioned, and the spring force of the elastic member 95 is applied to the motor MT. Only the state that is hanging.

  Thus, the motor MT moves when the shaft support member 93 pushes the elastic member 95. The elastic member 95 serves as a cushion. For example, even when the motor MT is further pushed leftward in a state where the left end portion of the motor MT in FIG. 1 is in contact with the shaft support member 91, the force is absorbed by the elastic member 95. As a result, excessive force is not applied to the motor MT, and damage to the motor MT is prevented.

  (Step 6) When the position of the motor MT with a rotary transformer is determined, the column portions 51a and 51b, the shaft support members 91 and 93, and the shaft S1 are quickly fixed with an adhesive. At this time, the bearing holders 12 and 14 may also be fixed together with an adhesive. When the pressure input between the shaft support members 91 and 93 and the base housing B is strong, the shaft support members 91 and 93 and the shaft S1 may be bonded with at least an adhesive.

  In positioning, when the motor MT is pushed by the left shaft support member 91 in FIG. 1, the pressure applied to the motor MT is absorbed by the elastic member 95. As a result, excessive force is not applied to the motor MT, and damage to the motor MT is prevented. That is, the force applied to the motor MT is the same whether the motor MT is pushed from the right or the left.

  In FIG. 1, the same groove as the right bearing holder 14 may be formed in the left bearing holder 12, and an elastic member may be disposed between the left bearing holder 12 and the left shaft support member 91. In particular, when an appropriate spring force cannot be set only on one side due to the storage space of the right elastic member 95, it is conceivable to use both sides (two springs).

  In this embodiment, a groove is formed in the bearing holder 14 and the elastic member 95 is installed therein (the elastic member 95 is accommodated in the motor MT). The elastic member 95 may be disposed between the bearing holder 14 of the motor MT and the shaft support member 93 by passing the shaft S <b> 1 through the elastic member (coil spring) 95.

  As the elastic member 95, an elastic body such as a plate spring or rubber can be used in addition to a coil spring.

  The spring force of the elastic member 95 is smaller than the adhesive strength between the bearing holders 12 and 14 of the motor MT and the shaft S1, and the shaft support member 93 and the shaft S1 are not bonded together. The spring force is such that the motor MT can be moved when 93 pushes the elastic member 95. If the spring force is too strong (the elastic coefficient of the elastic member 95 or the spring constant is large), there is no point in inserting the elastic member 95, and the motor MT is likely to be damaged during assembly (the bearing holder 12 with the rotary transformer, 14 and the shaft S1 are easily broken). On the other hand, when the spring force is too weak (the elastic coefficient or the spring constant is small), when the shaft support member 93 pushes the elastic member 95 in a state where the shaft support member 93 and the shaft S1 are not bonded. This is because the elastic member 95 is immediately deformed, the pressing force is absorbed by the elastic member 95, and the motor MT cannot be moved.

  Therefore, the spring force needs to be sufficiently smaller than the adhesive strength between the bearing holders 12 and 14 with the rotary transformer and the shaft S1, and the influence of the own weight of the motor MT and the frictional force between the shaft S1 and the shaft support member 93 is affected. It is necessary to have a size that allows the motor MT to be sufficiently positioned without receiving.

  In this embodiment, the spring force is set to about 10 gf. The spring constant is 0.095 N / mm, the natural length is 1.5 mm, and the mounting length is 0.3 mm.

  In the completed motor MT, since the bearing holder, the shaft support member, and the shaft are fixed by adhesion, the motor MT does not move relative to the base housing B during operation of the motor MT.

[Modification]
FIG. 4 is a partially enlarged view showing a modification in the vicinity of the right end portion of the shaft S1 shown in FIG.

  In the above-described embodiment (FIGS. 1 and 2), the outer peripheral portion of the central cylindrical portion of the shaft support members 91, 93 is fitted (fitted, press-fitted) into the openings 81a, 81b of the support columns 51a, 51b. Was adopted.

  The present invention is not limited to this, as shown in FIG. 4, a screw (male screw) is formed on the outer peripheral portion of the central cylindrical portion of the shaft support member 93a, and a screw (on the inner periphery of the openings 81a and 81b of the support column 51c) The collar may be moved by forming a female screw), screwing the male screw into the female screw, and turning the shaft support member 93a on which the male screw is formed.

  That is, in this modification, the shaft support member 93 a is fitted into the openings 81 a and 81 b by the screw mechanism 98. In addition, the structure which made the shaft support member 93 fit to the through-hole formed in the center of the screw member which formed the external thread may be sufficient.

  The threaded portion may be formed on only one of the left and right shaft support members (and either one of the opening portions of the supporting column corresponding thereto) or on both.

  The above embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 3 Bearing 7 Magnetic plate 4a, 5a, 4b, 5b Rotary transformer 11-14 Bearing holder 30a, 30b Rotary transformer 51a, 51b Support | pillar part 53 Connection part 59a, 59b Inclination part 71 MR (magnetoresistance effect) element (Z phase)
73 relay amplifier board 81a, 81b opening 90 encoder magnet 91, 93 collar (an example of a shaft support member)
95 Coil spring (an example of an elastic member)
98 Screw mechanism B Base housing m Magnet Mr Rotor Ms Stator MT Motor P Z phase pin S1 Shaft

Claims (8)

A motor including a rotor, a stator, and a rotary transformer;
A base housing including a post portion;
A shaft support member attached to the support column and supporting the shaft of the motor;
A motor with a rotary transformer, comprising: an elastic member provided between the shaft support member and the motor.   The motor with a rotary transformer according to claim 1, wherein the elastic member is a coil spring.   The motor with a rotary transformer according to claim 1 or 2, wherein the shaft support member and the support column are screwed together. The rotor has a magnet,
The stator has a coil;
The motor with a rotary transformer according to any one of claims 1 to 3, wherein the shaft support member and the shaft are bonded.   The spring force of the elastic member is smaller than the adhesive strength between the bearing holder of the motor and the shaft, and in the state where the shaft support member and the shaft are not bonded, the shaft support member The motor with a rotary transformer according to any one of claims 1 to 4, wherein the motor has a spring force that can move the motor when the elastic member is pressed. A method of manufacturing a motor with a rotary transformer, wherein a motor including a rotor, a stator, and a rotary transformer is fixed to a base housing including a support portion.
The shaft of the motor is engaged with the column through a shaft support member that is attached to the column and supports the shaft of the motor, and an elastic member is provided between the shaft support and the motor. Placing step;
A method of manufacturing a motor with a rotary transformer, comprising: a step of moving the motor when the shaft support member pushes the elastic member. The shaft support member is fitted to the support column,
The shaft support member and the shaft are a clearance fit,
The method for manufacturing a motor with a rotary transformer according to claim 6, further comprising a step of bonding the shaft support member and the shaft after the motor is axially adjusted by the step of moving the motor. . A shaft,
A bearing holder attached to the shaft;
A rotary transformer attached to the bearing holder;
A motor with a rotary transformer, wherein a groove into which an elastic member can be inserted from the outside is formed in the bearing holder.

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