KR20170026499A - Direct drive motor, transport device, inspection device, and machine tool - Google Patents

Abstract

A direct drive motor for improving the detection accuracy of the rotation state, a transfer device using this direct drive motor, an inspection device, and a machine tool. A motor unit 9 having a stator 13 and a rotor 15 rotatable with respect to the stator 13, a housing inner 3 to which the stator 13 is fixed, a rotor flange A bearing 11 which rotatably supports the rotor flange 5 with respect to the housing inner 3 and a bearing ring 3 which is rotatable in the axial direction of the fixed wheel 21 of the bearing 11 together with the housing inner 3, And a resolver 27 for detecting the rotation state of the motor unit 9. The resolver 27 is connected to the resolver rotor 33 and the inner ring pushing member 29, And the resolver rotor 33 is fixed directly to the rotor flange 5 and the resolver stator 35 is fixed directly to the inner ring press 29 have.

Description

TECHNICAL FIELD [0001] The present invention relates to a direct drive motor, a transfer device, an inspection device, and a machine tool,

The present invention relates to a direct drive motor, a transfer apparatus using the direct drive motor, an inspection apparatus, and a machine tool.

In general, a direct drive motor (hereinafter, also referred to as a DD motor) employing a drive system (a motor-load direct drive type drive system) in which a rotational force is directly transmitted to a rotational body and the rotational body is rotated in a predetermined direction with respect to the entire body, Is known. This type of DD motor is provided with a motor section, a bearing, a rotation detector (resolver) and a housing, and the entirety of the DD motor is formed into a substantially cylindrical shape. In order to achieve miniaturization of the conveying device, the inspection device, the machine tool, etc. in which the DD motor is used, it is necessary to use a flat structure in which the installation area (so-called footprint) of the housing of the DD motor and the height of the housing in the axial direction are reduced . For this reason, in order to reduce the footprint of the DD motor, conventionally, a structure in which the motor portion, the bearing, and the rotation detector (resolver) are arranged in the axial direction has been proposed (for example, see Patent Document 1).

Japanese Unexamined Patent Application Publication No. 2012-178926

However, in order to position the DD motor while rotating the output shaft with high accuracy, it is necessary to control the rotation state of the DD motor by detecting it with higher accuracy. For this reason, components constituting the DD motor are required to have high dimensional accuracy. A margin for permitting the dimensional tolerance of each component is required in order to prevent each component from interfering with stress when each component is combined. On the other hand, if the number of parts increases, the dimensional accuracy when the DD motor is assembled due to the margin of each component may be lowered. Particularly, when the mounting position of the resolver used as the rotation detector for detecting the rotation state becomes non-uniform, the rotation state of the DD motor can not be detected with high accuracy, and there is a possibility that the control precision is lowered.

In addition, when the resolver receives magnetic flux from the motor unit, there is a possibility that the detection accuracy of the rotation state of the DD motor is adversely affected.

Conventionally, a method of mounting a resolver on a structure of a DD motor formed of a magnetic material through a mounting member of a non-magnetic material to prevent the inflow of magnetism from the motor unit into the resolver and increasing the detection accuracy of the rotation state of the DD motor Was adopted. However, in this case, the parts constituting the DD motor are increased. Therefore, there is a possibility that the positional deviation of the resolver rotor and the resolver stator due to the dimensional tolerance between the respective components becomes large. In addition, as the number of parts constituting the DD motor increases, the number of manufacturing steps also increases, which may increase the cost of the DD motor and the production cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a direct drive motor which improves the detection accuracy of the rotation state, a transfer device using the direct drive motor, an inspection device, and a machine tool.

According to a first aspect of the present invention, there is provided a stator comprising: a stator; a motor section having a rotor rotatable relative to the stator; a first housing to which the stator is fixed; a second housing to which the rotor is fixed; A fixed wheel pressing member composed of a nonmagnetic material that axially holds the fixed wheel of the bearing together with the first housing; Wherein the rotation detector includes a resolver rotor and a resolver stator disposed opposite to the resolver rotor, wherein the resolver rotor is directly fixed to the second housing, and the resolver stator is directly fixed to the fixed wheel pushing member And the fixed drive motor is fixed.

According to the first aspect of the present invention, it is possible to suppress the influences of magnetic flux from the motor section to the resolver stator and the accuracy of detection of the rotational angular position of the second housing by both the resolver rotor and the resolver stator positional deviation And the rotation state of the motor unit can be detected with high accuracy.

In a second aspect of the present invention, in the direct drive motor of the first aspect, the stationary wheel pressing member may have a rectangular cross section in the radial direction. According to this configuration, the detection accuracy of the rotational angle position of the second housing can be made more accurate, and the rotation accuracy of the direct drive motor can be increased.

In a third aspect of the present invention, in the direct drive motor of the first aspect, the non-magnetic material constituting the fixed wheel pressing member may be an austenitic stainless steel. According to this structure, the direct drive motor can have a high rigidity structure, and the accuracy of detection of the rotation angle position of the second housing and the rotation accuracy of the direct drive motor can be further improved.

In a fourth aspect of the present invention, in the direct drive motor of the first aspect, the rotation detector may be a single incremental incremental resolver that detects the relative displacement of the rotor with respect to the stator. According to this configuration, the height dimension in the axial direction of the direct drive motor can be reduced, and the direct drive motor can be downsized in the axial direction.

A fifth aspect of the present invention is the direct drive motor according to the fourth aspect of the present invention, further comprising: a power factor detecting section for detecting a position where the power factor becomes 0 at the time of turning on power to the motor section; And a current control section for controlling the current flow of the motor section according to the incremental information. According to this configuration, even in a configuration in which a single resolver is mounted, the rotation state of the direct drive motor can be detected with high accuracy.

In a sixth aspect of the present invention, in the direct drive motor of the first aspect, the motor portion, the bearing, and the resolver may be arranged in the axial direction of the bearing. According to this configuration, it is possible to suppress the enlargement of the direct drive motor in the radial direction, and to reduce the footprint.

A seventh aspect of the present invention is the direct drive motor according to the first aspect of the present invention, wherein the second housing includes: a flange portion extending to one axial end face side of the rotating wheel of the bearing; And a rotary wheel pressing member disposed on the end face side. According to this structure, even if the adhesive force of the filler filled in the fitting surface between the bearing and the second housing is lowered, it is possible to prevent the bearing and the second housing from being detached.

According to an eighth aspect of the present invention, in the direct drive motor of the first aspect, the second housing includes: a flange portion extending to one axial end face side of the rotational wheel of the bearing; And the second housing and the rotating wheel may be fixed with a filler. In addition, the second housing and the rotating wheel may be fixed with a filler. According to this structure, even if the adhesive force of the filler filled in the engagement surface of the bearing and the second housing is lowered, the bearing and the second housing can be prevented from being separated by the rotation wheel pressing member.

In a ninth aspect of the present invention, in the direct drive motor of the seventh or eighth aspect, the rotating wheel pressing member may be a C-shaped retaining ring. According to this structure, even if the adhesive force of the filler filled in the fitting surface between the bearing and the second housing is lowered, it is possible to prevent the bearing and the second housing from being detached.

A tenth aspect of the present invention is the direct drive motor according to the first aspect of the present invention, in which the second housing is formed in a substantially cylindrical shape and is disposed on the outer side of the first housing with respect to the axis of the bearing, It may be a one-piece structure without cutting scale. According to this configuration, the bearing can be supported without enlarging the second housing in the axial direction, and the size of the direct drive motor can be reduced.

An eleventh aspect of the present invention provides a transporting device provided with a direct drive motor according to any one of the first to tenth aspects and carrying a transported article by rotation of the second housing. According to this configuration, it is possible to increase the positional accuracy at the time of conveying the conveyed object, and realize the downsizing of the conveying device.

The twelfth aspect of the present invention provides an inspection apparatus provided with a direct drive motor according to any one of the first to tenth aspects and including an inspection unit for individually inspecting an object moving by rotation of the second housing . According to this configuration, it is possible to increase the positional accuracy at the time of moving the object to the inspection unit, and realize the miniaturization of the inspection apparatus.

A thirteenth aspect of the present invention provides a machine tool comprising a direct drive motor according to any one of the first to tenth aspects and a machining section for individually machining the moving object by rotation of the second housing . According to this configuration, it is possible to increase the positional accuracy when the object is moved to the machining portion, and realize the miniaturization of the machine tool.

According to an aspect of the present invention, there is provided a direct drive motor, a transfer device using the direct drive motor, an inspection apparatus, and a machine tool capable of improving the detection accuracy of the rotation state.

1 is a cross-sectional view showing a configuration of a direct drive motor according to the present embodiment.
2 is a block diagram showing a configuration for controlling the rotation angle position of the direct drive motor according to the present embodiment.
3 is a schematic configuration diagram of a testing apparatus using a direct drive motor according to the present embodiment.
4 is a schematic configuration diagram of a machine tool using the direct drive motor according to the present embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A mode (embodiment) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments. In addition, the constituent elements described below include those which can be readily devised by those skilled in the art, and substantially the same. In addition, the constituent elements described below can be suitably combined.

1 is a cross-sectional view showing a configuration of a direct drive motor 10 according to the present embodiment. A direct drive motor (hereinafter referred to as a DD motor) 10 directly transmits a rotational force to a rotating body without interposing a decelerating mechanism (for example, a reduction gear, a transmission belt, etc.) Can be rotated in a predetermined direction.

The DD motor 10 of the present embodiment is configured as a so-called outer rotor type. 1, the DD motor 10 includes an annular housing inner (first housing) 3 fixed to a base 1 and an annular outer housing 3 fixed to the outer periphery of the housing inner 3, A housing 7 having a rotor flange 5 and a rotor flange 5 disposed on the inner periphery of the housing inner 3 so as to be rotatable relative to the housing inner 3, And a bearing 11 for rotatably supporting the rotor flange 5 on the housing inner 3.

The housing inner 3 and the rotor flange 5 are each formed into a substantially cylindrical shape having different diameters and arranged concentrically with respect to the rotation axis S. The rotor flange 5 is a one-piece structure in which there is no cutting scale in the axial direction of the rotary shaft S (vertical direction in Fig. 1). That is, the rotor flange 5 is formed in a substantially cylindrical shape continuous over the entire circumference from the lower end portion to the upper end portion in the axial direction of the rotary shaft S, and various works (not shown) are mounted on the upper end portion . By rotating the rotor flange 5 by the motor portion 9, various kinds of work can be rotated together with the rotor flange 5 in a predetermined direction. Thus, the rotor flange 5 rotates around the rotation axis S by the operation of the motor section 9, and thus functions as an output shaft. The bearing inner member 3 is formed in a substantially cylindrical shape extending continuously from the lower end portion to the bearing 11 in the axial direction of the rotary shaft S. The bearing inner member 3 is pressed against the inner ring (Pressing member) 29 as shown in Fig. In the present embodiment, the housing inner 3 and the rotor flange 5 are made of a magnetic material, and the inner ring press 29 is made of a non-magnetic material. The reason will be described later.

Instead of an annular shape in which the cross-sectional shape in the radial direction is L-shaped as shown in Fig. 1, the inner ring press 29 may have an annular shape such as a rectangular shape or a square shape do. In this way, the parallelism and the planarity of both end faces in the axial direction can be easily made highly accurate.

The motor portion 9 is disposed at the lower portion of the housing 7 (in the vicinity of the base 1). The motor section 9 includes a stator 13 fixed to the outer circumferential surface of the housing inner 3 and a rotor 13 fixed to the inner surface of the rotor flange 5 and opposed to the stator 13 (15). The stator 13 includes a plurality of motor cores 17 arranged concentrically at predetermined intervals (for example, at equal intervals) in the circumferential direction (the rotational direction of the rotor flange 5) And a stator coil 19, in which a plurality of element wires are wound around the stator coil 17, is fixed. Wiring for supplying electric power from the control unit 20 (Fig. 2) is connected to the stator 13, and electric power is supplied to the stator coil 19 through the wirings. The rotor 15 is constituted by a plurality of permanent magnets arranged concentrically at a predetermined interval (for example, at equal intervals) along the circumferential direction (rotational direction of the rotor flange 5). When the stator coil 19 is energized through the control unit 20, a rotational force is applied to the rotor flange 5 in accordance with Fleming's left-hand rule, and the rotor flange 5 rotates in a predetermined direction.

The bearing 11 is disposed at a position farther from the base 1 in the axial direction than the motor portion 9. The bearing 11 includes an inner ring (fixed wheel) 21 and an outer ring (rotating wheel) 23 disposed so as to be relatively rotatable and opposed to each other and a plurality And a rolling body 25 of the rolling bearing. It is preferable that the bearing 11 is capable of loading both an axial load and a moment load with one. For example, a four-point contact ball bearing, a three-point contact ball bearing, a deep groove ball bearing, Etc. may be employed. In the case of employing a cross roller bearing, it is preferable to use a structure in which both the inner and outer rings are of a single structure, not the general inner or outer ring being a divided structure. The inner ring 21 is sandwiched between the inner ring 3 and the inner ring press 29 and the outer ring 23 is fixed to the inner circumferential surface of the rotor flange 5. The supporting structure of the bearing 11 will be described later.

The DD motor 10 is disposed at a position above the bearing 11 (i.e., at a position farther away from the base 1 in the axial direction than the bearing 11) (Rotation detector) 27 for detecting a rotation direction, a rotation direction, a rotation angle, and the like. Accordingly, various workpieces mounted on the rotor flange 5 can be accurately rotated by a predetermined angle, and can be accurately positioned at a target position. The resolver 27 is protected from the external environment by a disc-shaped cover 31 provided on the upper portion of the inner ring press 29 connected to the housing inner 3.

In the present embodiment, the DD motor 10 is arranged so that the motor section 9, the bearing 11 and the resolver 27 are arranged in the housing 7 so as to be aligned in the axial direction of the rotary shaft S And are arranged in a row. Accordingly, in the DD motor 10, the increase in the diameter direction around the rotation axis S is suppressed, so that the installation area (so-called footprint) of the housing 7 can be reduced. On the other hand, in recent years, there has been a demand for a DD motor in which not only the mounting area of the housing but also the height dimension in the axial direction is reduced.

In this embodiment, only a single resolver 27 is disposed in the housing 7. The resolver 27 is an incremental resolver that detects the relative displacement of the rotor 15 with respect to the stator 13. The resolver 27 includes an annular resolver rotor 33 having an inner periphery eccentric to the rotation axis S and a ring-shaped resolver rotor 33 disposed to face the inner side of the resolver rotor 33, And a resolver stator 35 for detecting a change in reluctance between the resolver rotor 33 and the resolver rotor. As described above, since only one resolver 27 is disposed in the housing 7, it is possible to reduce the number of revolutions of the resolver 10 relative to the arrangement of the two resolvers, that is, the absolute resolver and the incremental resolver, The height dimension in the axial direction can be reduced.

The resolver rotor 33 is directly mounted and integrated with the resolver rotor fixing portion 5a formed on the inner peripheral surface of the rotor flange 5 by the bolt 33a without interposing another member. The resolver stator 35 is directly mounted and integrated with the resolver stator fixing portion 29a formed on the outer peripheral surface of the inner ring pressing portion 29 by bolts 35a without interposing another member.

By varying the distance between the resolver rotor 33 and the resolver stator 35 in the circumferential direction by eccentricity of the resolver rotor 33, the reluctance changes depending on the position of the resolver rotor 33. Thereby, the fundamental wave component of the change of the reluctance becomes one cycle with respect to one rotation of the rotor flange 5. The resolver 27 outputs a resolver signal (incremental information) which changes in accordance with the rotation angle position of the rotor flange 5. [

2 is a block diagram showing a configuration for controlling the rotation angle position of the DD motor 10 according to the embodiment. To the DD motor 10, a control unit 20 for controlling the operation of the DD motor 10 is connected. The control unit 20 includes a power factor detecting section 41 for detecting a position where the power factor becomes zero when the power is supplied to the motor section 9 and a control section 40 for controlling the motor section 9 based on the position where the power factor is 0 and the resolver signal. And a current control section 43 for controlling the current of the battery 9.

In the present embodiment, the power factor detecting section 41 detects the position of the resolver rotor 33 whose power factor becomes zero when power is supplied to the motor section 9 (stator coil 19) As a reference position. Then, this reference position is outputted to the current control section 43. [ The current control section 43 acquires the resolver signal detected by the resolver 27 and detects the change of the resolver signal and the current of the motor current (current) flowing to the motor section 9 ) Timing. Accordingly, since the absolute resolver becomes unnecessary when detecting the current timing of the motor current, there is no need to mount two types of rotation detectors, an absolute resolver and an incremental resolver. Therefore, a single resolver configuration can be achieved, and the height of the DD motor 10 in the axial direction can be suppressed.

Next, the supporting structure of the outer ring (turning wheel) 23 of the bearing 11 will be described. An outer ring fixing portion 50 having a width corresponding to the axial height of the bearing 11 is formed around the entire circumference on the inner circumferential surface of the rotor flange 5 and on the resolver 27 side of the outer ring fixing portion 50, A flange portion 51 whose diameter is smaller than the outer diameter of the outer ring (rotating wheel) 23 of the bearing 11 and protrudes inward is formed over the entire circumference. A groove portion 52 whose diameter is wider than the outer diameter of the outer ring (wheel) 23 of the bearing 11 is formed on the side of the motor portion 9 of the outer ring fixing portion 50.

The flange portion 51 extends toward one axial end surface (the end surface on the resolver 27 side) 23a of the outer ring (rotation wheel) 23. The flange portion 51 is formed such that the inner circumferential surface 51b of the flange portion 51 is located on the outer side of the inner circumferential surface of the outer ring (the turning wheel) 23 and is located further inside than the chamfering portion of the outer ring As shown in FIG. According to this structure, the outer ring (turning wheel) 23 of the bearing 11 can be reliably supported by the flange portion 51.

An outer ring pushing (rotating wheel pushing member) 53 having a spring force to be inflated in the outer diameter direction is mounted on the groove portion 52. The outer ring pushing 53 is engaged with the outer ring pushing (The end face on the side of the motor unit 9) 23b in the axial direction. The outer diameter of the groove portion 52 is slightly larger than the outermost diameter of the outer ring (rotation wheel) 23 of the bearing 11 so that the allowable load of the bearing 11 itself is not lost even if it is applied to the outer ring press 53. As the outer ring press 53, for example, a C-type retaining ring or spring ring may be used.

A filler (for example, a mold agent and an adhesive) is filled in the gap between the outer ring (rotation wheel) 23 of the bearing 11 and the outer ring fixing portion 50 formed on the rotor flange 5, As the filler solidifies, the bearing 11 and the rotor flange 5 are fixed.

As described above, the outer ring (rotating wheel) 23 of the bearing 11 is supported by the flange portion 51 provided at the upper and lower ends (both ends) in the axial direction of the outer ring fixing portion 50 and the outer ring pressing portion 53 in the axial direction The filler filled in the gap between the bearing 11 and the outer ring fixing portion 50 is solidified and fixed.

With this configuration, even if the fixing force is lowered due to breakage or deterioration of the filler, it is possible to prevent the outer ring press 53 from detaching the rotatable wheel 23 from the rotor flange 5.

Next, the supporting structure of the inner ring (fixed wheel) 21 of the bearing 11 will be described. The inner ring (fixed wheel) 21 of the bearing 11 is fixed to the inner ring 3 and the inner ring press 29 after the rotor flange 5 and the outer ring (rotating wheel) 23 of the bearing 11 are fixed And the inner ring (fixed wheel) 21 of the bearing 11 is fixedly supported in the axial direction by engaging with a plurality of bolts 35b. In this embodiment, the bolt 35b for inserting and fixing the inner ring 3 and the inner ring press 29 is different from the bolt 35a for fixing the resolver stator 35 to the inner ring press 29 It is a separate part.

The outer diameter of the inner ring press 29 is larger than the inner diameter of the inner ring (fixed ring) 21 of the bearing 11. The outer edge portion of the inner ring press 29 extends toward one axial end surface (the end surface on the resolver 27 side) 21a of the inner ring (fixed wheel) 21. The outer ring portion of the inner ring pressing portion 29 is located on the inner side of the outer peripheral surface of the inner ring (fixed wheel) 21 and is located outside the chamfering portion of the inner ring . According to this, the inner ring (fixed wheel) 21 of the bearing 11 can be reliably supported by the inner ring press 29.

An inner ring fixing portion 60 having a width corresponding to the axial height of the bearing 11 from the upper end portion is formed on the outer circumferential surface of the housing inner member 3 over its entire periphery. A flange portion 61 is formed on the side of the portion 9 so as to extend outwardly from the entire periphery by enlarging the diameter of the inner ring (fixed wheel) 21 of the bearing 11 to a diameter larger than the inner diameter.

The flange portion 61 extends toward the other end face (the end face on the side of the motor portion 9) 2lb of the inner ring (fixed wheel) 21 in the axial direction. The outer peripheral surface 61b of the flange portion 61 is located on the inner side of the outer peripheral surface of the inner ring (fixed wheel) 21 and the flange portion 61 is located on the outer side of the chamfered portion of the inner ring As shown in FIG. According to this, the inner ring (fixed wheel) 21 of the bearing 11 can be surely supported by the flange portion 61. [

A gap between the inner ring (fixed wheel) 21 of the bearing 11 and the inner ring fixing portion 60 formed in the housing inner 3 is filled with a filler (e.g., a mold agent and an adhesive) As the filler solidifies, the bearing 11 and the housing inner 3 are fixed.

The inner ring (fixed wheel) 21 of the bearing 11 is axially held between the inner ring pressing portion 29 and the inner ring fixing portion 60 by the flange portion 61 provided at the lower end in the axial direction, The filler filled in the gap between the bearing 11 and the inner ring fixing portion 60 is solidified and fixed.

Here, in the DD motor 10 according to the present embodiment, the housing inner 3 and the inner ring press 29 are defined as a structure constituting the fixed portion of the DD motor 10, and the rotor flange 5 is defined as DD And is defined as a structure constituting the rotating portion of the motor 10. [

For example, in the structure in which the structure constituting the rotating portion is composed of the lower rotor flange member and the upper outer ring pressing member, and the outer ring pressing member and the rotor flange member sandwich the outer ring (rotating wheel) of the bearing, It is necessary to fix the member and the rotor flange member by inserting a plurality of bolts or the like. In such a configuration, the bearing is fixed by clamping the outer ring (rotating wheel) of the bearing with the outer ring pressing member and the rotor flange member to fasten the bolt. However, with this configuration, the number of components constituting the DD motor increases, There is a possibility that the dimensional accuracy when the DD motor is assembled is lowered by the margin for allowing the dimensional tolerance.

In the present embodiment, as described above, the rotor flange 5, which is a structure constituting the rotating portion of the DD motor 19, has a one-piece structure having no cutting scale in the axial direction of the rotating shaft S And is formed in a substantially cylindrical shape continuous from the lower end portion to the upper end portion in the axial direction of the rotary shaft S over the entire circumference. Thus, it is possible to suppress deterioration in dimensional accuracy when the DD motor 10 is assembled. In addition, since the number of parts for constructing the DD motor 10 is reduced, the cost and manufacturing cost of the DD motor 10 can be reduced.

In the present embodiment, as described above, since only the single resolver 27 is disposed in the housing 7, the height dimension in the axial direction of the DD motor 10 can be reduced, , The height dimension in the axial direction of the rotor flange 5 can be reduced. As a result, the amount of material used for the rotor flange 5 can be reduced, contributing to the cost reduction of the DD motor 10. [

In addition, a structure (rotor flange, housing inner, bearing, inner ring press, etc.) of a DD motor is generally made of a magnetic material. On the other hand, since the resolver 27 detects the rotational angle position of the rotor flange 5 by performing the magnetic sensing as described above, the rotor flange 5 The detection accuracy of the rotation angle position of the rotation angle sensor may be adversely affected.

Here, for example, if the structure constituting the fixed portion is constituted by one housing inner member, in order to avoid the influences of the inflow of magnetism from the motor portion through the housing inner member made of the magnetic material, It is necessary to mount the resolver stator to the housing inner member via a mounting member or the like made of another non-magnetic material.

In this embodiment, as described above, the housing inner 3 and the housing inner 3 constitute the fixed portion by the inner ring pressing 29 composed of a non-magnetic material holding the bearing 11 together, And the bolts 35b for inserting and fixing the housing inner 3 and the inner ring press 29 are separate parts different from the bolts 35a for fixing the resolver stator 35 to the inner ring press 29 . That is, the housing inner member 3 made of a magnetic material and the resolver stator 35 are not connected to each other.

This makes it possible to suppress the influence on the detection accuracy of the rotational angle position of the rotor flange 5 due to the inflow of magnetic force from the motor unit 9 and to improve the detection accuracy of the rotational angle position of the rotor flange 5 . Since there is no need to interpose another component between the resolver stator 35 and the inner ring press 29, it is possible to suppress the deviation of the mounting position of the resolver stator 35, The detection accuracy of the angular position can be further improved. In addition, since the rotor flange 5 has a one-piece structure and the number of parts constituting the DD motor 10 can be reduced, the cost and production cost of the DD motor 10 can be further reduced.

As described above, when the inner ring press 29 is formed into an annular shape whose cross section in the radial direction becomes a rectangular shape or a square shape, it is possible to easily make the parallelism and the planar view of the axial direction end face easily and accurately . This makes it possible to further suppress the deviation of the mounting position of the resolver stator 35 by using the axial upper end surface as the mounting surface of the resolver stator 35. Therefore, the detection accuracy of the rotational angle position of the rotor flange 5 can be improved The rotational accuracy of the DD motor 10 can be improved by making the lower end surface in the axial direction a bearing holding surface.

In addition, by using the austenitic stainless steel as the material of the inner ring press 29, high rigidity can be obtained as compared with the case where the inner ring press 29 is formed of another nonmagnetic material such as aluminum. The austenitic stainless steel can be machined with high precision compared with other nonmagnetic materials such as aluminum and the material of the inner ring press 29 is made of an austenitic stainless steel, The influence of the rotational angle position of the rotor flange 5 on the detection accuracy can be suppressed and the positional accuracy of the resolver stator 35 can be improved. And the rotational accuracy of the DD motor 10 can be further increased.

3 is a schematic configuration diagram of the inspection apparatus 100 using the DD motor 10 according to the present embodiment. A table 80 on a disk is connected to the upper end of the rotor flange 5 of the DD motor 10 and the table 80 is rotated by the operation of the rotor flange 5. An object to be inspected (a conveyed object) 81 is disposed at an equal interval on the edge of the table 80. In this configuration, the object to be inspected 81 is rotated and transported together with the table 80 by the operation of the DD motor 10, so that the DD motor 10 and the table 80 are provided, do. Above the edge of the table 80 is disposed a camera (examining unit) 82 for individually observing the object 81 to be inspected rotated (conveyed) together with the table 80. Then, by photographing with the camera 82, it is possible to inspect the object 81 to be inspected based on the photographed image. According to this configuration, it is possible to increase the positional accuracy when the object to be inspected 81 is moved downward of the camera 82, and to realize the downsizing of the inspection apparatus 100.

4 is a schematic configuration diagram of the machine tool 101 using the DD motor 10 according to the present embodiment. A table 80 on a disk is connected to the upper end of the rotor flange 5 of the DD motor 10 and the table 80 is rotated by the operation of the rotor flange 5. An object to be processed (object) 91 is disposed at an equal interval on the edge of the table 80. A loading robot (processing portion) for carrying out processing for loading new components 92 and 93 is disposed on the object to be processed 91 at the edge of the table 80, The processing object 91 can be machined. According to this configuration, it is possible to increase the positional accuracy when the object 91 is moved to the position of the loading robot, and realize the downsizing of the machine tool 101. [

As described above, according to the present embodiment, the motor portion 9 having the stator 13 and the rotor 15 rotatable with respect to the stator 13, and the housing inner portion A rotor flange (second housing) 5 to which the rotor 15 is fixed and a rotor flange (second housing) 5 with respect to the housing inner (first housing) 3 A bearing 11 that is freely rotatable and an inner ring pushing member (not shown) made of a nonmagnetic material that axially holds the inner ring (fixed ring) 23 of the bearing 11 together with the housing inner (first housing) A fixed wheel pressing member) 29, and a resolver 27 for detecting the rotational state of the motor unit 9. [ The resolver 27 is composed of a resolver rotor 33 and a resolver stator 35 disposed to face the resolver rotor 33. Further, the resolver rotor 33 is directly fixed to the rotor flange (second housing) 5, and the resolver stator 35 is directly fixed to the inner ring pushing (fixed ring pressing member) 29. With this configuration, detection of the rotational angular position of the second housing by both the inflow of magnetic force from the motor section 9 to the resolver stator 35 and the positional deviation of the resolver rotor 33 and the resolver stator 35 The influence on the accuracy can be suppressed and the rotation state of the motor unit 9 can be detected with high accuracy. In addition, it is possible to suppress the increase in the number of components constituting the DD motor 10, and to reduce the cost and production cost of the DD motor 10. [

According to the present embodiment, the resolver 27 is a single incremental incremental resolver that detects the relative displacement of the rotor 15 with respect to the stator 13. With this configuration, the height dimension in the axial direction of the housing 7 can be reduced, and the size of the DD motor 10 in the axial direction can be reduced.

According to the present embodiment, there are provided a power factor detecting section 41 for detecting a position where the power factor becomes 0 at the time of turning on the power to the motor section 9, And a current control section 43 for controlling the current flow of the motor section 9 by the current control section 43. [ With this configuration, the absolute resolver becomes unnecessary when detecting the timing of the commutation of the motor current (current). Therefore, there is no need to mount two types of rotation detectors, an absolute resolver and an incremental resolver, and a single resolver configuration can be achieved. Therefore, the rotation state of the motor section 9 can be detected with high accuracy, and the height of the DD motor 10 in the axial direction can be suppressed.

According to the present embodiment, the motor portion 9, the bearing 11, and the resolver 27 are arranged in the axial direction of the bearing 11. With this configuration, it is possible to suppress the enlargement in the radial direction around the rotation axis S, and to reduce the installation area (so-called footprint) of the DD motor 10.

According to the present embodiment, the rotor flange (second housing) 5 includes a flange portion 51 extending toward one axial end surface 23a of the outer ring (rotation wheel) 23 of the bearing 11 (Outer ring pushing member) 53 disposed on the other end face 23b side of the outer ring (wheel) 23 in the axial direction. With this configuration, even if the adhesive force of the filler filled in the gap between the bearing 11 and the outer ring fixing portion 50 formed on the rotor flange (second housing) 5 is lowered, 1 housing) 5 can be prevented from being pulled out.

The rotor flange (second housing) 5 includes a flange portion 51 extending toward one axial end surface 23a of the outer ring (rotation wheel) 23 of the bearing 11, (Second housing) 5 and an outer ring (rotating wheel) 23, which are disposed on the side of the other end face 23b in the axial direction of the outer ring 23, Is fixed with a filler. Thus, even if the adhesive force of the filler filled in the gap between the bearing 11 and the outer ring fixing portion 50 formed on the rotor flange (second housing) 5 is lowered, the outer ring pushing It is possible to prevent the bearing 11 and the rotor flange (first housing) 5 from coming off.

Further, according to the present embodiment, the outer ring pressing (wheel pressing member) 53 is a C-type retaining ring. Even if the adhesive force of the filler filled in the gap between the bearing 11 and the outer ring fixing portion 50 formed on the rotor flange (second housing) 5 is lowered, the bearing 11 and the rotor It is possible to prevent the flange (first housing) 5 from being pulled out.

According to the present embodiment, the rotor flange (second housing) 5 is formed in a substantially cylindrical shape and disposed outside the housing inner (first housing) 3 with respect to the axial line of the bearing 11 , And it is a one-piece structure without a cutting scale in the axial direction. Thus, the bearing 11 can be supported while the rotor flange (second housing) 5 is prevented from being enlarged in the axial direction, and the size of the DD motor 10 can be reduced.

The embodiments have been described above, but the embodiments are not limited by the above description. Although the DD motor 10 of the present embodiment is of an outer rotor type, it goes without saying that it may be an inner rotor type. In the present embodiment, a structure including a single bearing 11 is described. However, in a structure in which a plurality of bearings are used in combination (including a case where a spacer is provided between a bearing and a bearing) The same effect can be obtained.

3: housing inner (first housing)
5: rotor flange (second housing)
7: Housing
9:
10: DD motor
11: Bearings
13: stator (stator)
15: rotor (rotor)
20: control unit
21: Inner ring (fixed ring)
21a: one axial end face (one axial end face) of the inner ring (fixed wheel)
2lb: the other axial end face (the other axial end face) of the inner ring (fixed wheel)
23: outer ring (wheel)
23a: one axial end face (one axial end face) of the outer ring (front wheel)
23b: another axial end surface (the other axial end surface) of the outer ring (front wheel)
25: rolling body
27: Resolver (rotation detector)
29: Pressing the inner ring (fixed wheel pressing member)
33: resolver rotor
35: resolver stator
41: Power factor detecting section
43:
51: flange portion (rotor flange)
52: Groove
53: Outer wheel pressing (wheel pressing member)
60: inner ring fixing portion
61: flange portion (housing inner)
80: Table
81: object to be inspected (return material)
82: camera (inspection part)
91: object to be processed (object)
100: Inspection device
101: Machine tools
S:

Claims (13)

A motor section having a stator and a rotatable rotor with respect to the stator,
A first housing to which the stator is fixed,
A second housing to which the rotor is fixed,
A bearing rotatably supporting the second housing with respect to the first housing,
An annular fixed ring pressing member composed of a nonmagnetic material for axially holding the fixed wheel of the bearing together with the first housing,
And a rotation detector for detecting a rotation state of the motor unit,
The rotation detector includes a resolver rotor and a resolver stator disposed opposite to the resolver rotor, wherein the resolver rotor is directly fixed to the second housing, and the resolver stator is fixed to the fixed wheel pressing member directly, motor. The method according to claim 1,
Wherein the fixed wheel pressing member has a rectangular cross-sectional shape in the radial direction. The method according to claim 1,
The nonmagnetic material constituting the fixed wheel pressing member is an austenitic stainless steel direct drive motor. The method according to claim 1,
Wherein the rotation detector is a single resolver incremental resolver that detects a relative displacement of the rotor with respect to the stator. 5. The method of claim 4,
A power factor detecting section that detects a position at which a power factor becomes zero at the time of turning on power to the motor section,
And a current control section for controlling a current of the motor section based on a position where the power factor becomes 0 and incremental information output from the resolver. The method according to claim 1,
Wherein the motor unit, the bearing, and the rotation detector are arranged in the axial direction of the bearing. The method according to claim 1,
And the second housing includes a flange portion extending to one axial end face side of the rotating wheel of the bearing and a rotating wheel pressing member disposed on the other axial end face side of the rotating wheel. motor. The method according to claim 1,
The second housing includes a flange portion extending to one axial end face side of the rotary wheel of the bearing, an annular groove formed on the other axial end face side of the rotary wheel, And the second housing and the outer rotating wheel are fixed with a filler. 9. The method according to claim 7 or 8,
The rotation wheel pressing member is a C-type retaining ring. The method according to claim 1,
Wherein the second housing is formed in a substantially cylindrical shape and disposed on the outer side of the first housing with respect to the axis of the bearing and has a unitary structure having no cut scale in the axial direction. A direct drive motor according to any one of claims 1 to 10,
And transports the transported object by the rotation of the second housing. 11. A direct drive motor comprising: a direct drive motor according to any one of claims 1 to 10;
And an inspection unit for individually inspecting an object moving by the rotation of the second housing. 11. A direct drive motor comprising: a direct drive motor according to any one of claims 1 to 10;
And a machining portion for individually machining the objects to be moved by the rotation of the second housing.

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