JP4701994B2 - Direct drive motor installation method and direct drive motor - Google Patents

Description

  The present invention provides a method for installing a direct drive motor while maintaining high accuracy of the motor output shaft (e.g., parallelism, runout accuracy during rotation), and high rigidity with excellent heat dissipation installed by the method. It relates to a direct drive motor.

  Conventionally, for example, various direct drive motors that directly transmit a rotational force to a rotating body without a reduction mechanism (for example, a reduction gear, a transmission belt, etc.) and rotate the rotating body in a predetermined direction are known. (See, for example, Patent Document 1). As a direct drive motor (hereinafter referred to as a DD motor), an outer rotor type and an inner rotor type are known. As an example, an outer rotor type DD motor as shown in FIG. An annular base 4 fixed to the base 2, a rotating body 6 (also referred to as a motor output shaft) supported so as to be rotatable with respect to the base 4, and the base 4 and the rotating body 6 are incorporated into the rotating body. And a motor 8 that rotates the motor 6 in a predetermined direction.

  The base 2 is formed with a fixed surface 2s having a flat finish, for example, and the base 4 of the DD motor is fixed to the fixed surface 2s with a fixing member (for example, a plurality of bolts 10). It has become. In this case, the base 4 rises along the rotation axis R of the rotating body (motor output shaft) 6 at the center side thereof, and an annular fixing portion 4a formed on the outer peripheral side and fixed to the fixing surface 2s. The hollow cylindrical portion 4b is provided, and the fixing portion 4a and the cylindrical portion 4b are integrated via an annular connecting portion 4c extending facing the fixing surface 2s of the base 2. Has been. Note that a hollow hole 4h penetrating along the rotation axis R is formed in the cylindrical portion 4b.

  Further, in the annular region surrounded by the fixed portion 4a, the cylindrical portion 4b, and the connecting portion 4c, the rotating body 6 is arranged to face each other so as to cover the outside of the cylindrical portion 4b. A bearing 12 is interposed between the rotating body 6 and the base 4 (for example, the cylindrical portion 4b). In this case, the bearing 12 is maintained in a state in which a predetermined preload is applied by the inner ring presser 4d formed on the cylindrical portion 4b and the outer ring presser 6a formed on the rotating body 6. Thereby, the rotating body 6 is supported so that it can always rotate stably and smoothly with respect to the base 4. Various workpieces (not shown) are attached to the rotating body 6 with bolts (only the mounting holes 6b for bolts are shown in FIG. 5A). Various workpieces can be rotated in a predetermined direction.

  Further, the inner ring presser 4d may be formed separately from the base 4 (cylindrical portion 4b) depending on the arrangement configuration and shape of the base 4 and the rotating body 6, or the base 4 (cylindrical shape). It may be formed integrally with the part 4b). Similarly, the outer ring presser 6 a may be formed separately from the rotating body 6 or may be formed integrally with the rotating body 6. As the bearing 12, for example, a ball bearing, a roller bearing, a cross roller bearing, or the like can be applied, but is not particularly limited here.

  As the motor 8 incorporated between the base 4 and the rotating body 6, for example, an electromagnet (stator) 8 a that is equally distributed along the base 4 (for example, the fixed portion 4 a), and the electromagnet 8 a are opposed to each other. Thus, it can be configured to include a permanent magnet (rotor) 8b equally arranged on the rotating body 6. In this configuration, when a current is passed through a coil (not shown) wound around the electromagnet 8a, the rotating body 6 passes through the permanent magnet 8b according to Fleming's left-hand rule due to the magnetic interaction between the electromagnet 8a and the permanent magnet 8b. Can be given rotational force. Thereby, the rotary body 6 can be rotated in a predetermined direction. The motor 8 is protected from the outside world and protected by a motor cover 14 screwed to the base 4 (for example, the fixed portion 4a).

  In addition, a sensor 16 that detects a rotation state (for example, a rotation angle) of the rotating body 6 is provided between the base 4 (for example, the cylindrical portion 4 b) and the rotating body 6. The sensor 16 is isolated and protected from the outside by a disc-shaped cover 18 provided on the upper portion of the cylindrical portion 4b. Thereby, for example, various workpieces (not shown) attached to the workpiece attachment surface 6s of the rotating body 6 are positioned with high accuracy at a predetermined rotation angle, or the workpiece is accurately rotated by a predetermined angle. It becomes possible to do. As the sensor 16, for example, a commercially available detection element such as a resolver may be applied.

  In such a DD motor, for example, as shown in FIG. 5B, the bolt 10 is screwed into the fixing hole 22 formed in the base 2 through the bolt hole 20 formed in the fixing portion 4 a of the base 4. By this, it can fix to the fixed surface 2s of the base 2. By the way, in the field of machine tools and the like, in order to stably fix a fixed object, a middle recess (recessed) with a bottom surface (fixed surface) of the fixed object recessed (recessed) based on JIS standard (JIS B 6159). It is common to use a shape of a beko). For this reason, in the conventional DD motor, the bottom surface 4s of the base 4 has a concave shape in which the central portion is recessed from the other portions (outer peripheral side).

  In this case, in a state where the DD motor is fixed to the base 2 (FIG. 5A), a hollow-shaped gap is formed between the bottom surface 4s of the base 4 and the fixing surface 2s of the base 2. . In the illustrated DD motor, the bottom surface 4s on the center side of the base 4 is most recessed, and the bottom surface 4s on the outer peripheral side (the bottom surface 4s of the fixing portion 4a) is fixed to the fixing surface 2s of the base 2 by the bolts 10. Has been. In this case, a substantially conical gap is formed between the bottom surface 4s of the base 4 and the fixed surface 2s of the base 2 with the center-side bottom surface 4s being the farthest from the fixed surface 2s.

  According to such a configuration, the base 4 is easily elastically deformed according to the size of the gap between the bottom surface 4 s of the base 4 and the fixed surface 2 s of the base 2, and thereby the rigidity of the entire DD motor. (For example, axial rigidity, moment rigidity, etc.) may become low. Such a decrease in rigidity increases as the thickness of the base 4 becomes thinner. For this reason, there is a limit to making the DD motor thinner by making the base 4 thinner.

  In this state where the base 4 is easily elastically deformed, for example, when an external force is applied to the work attached to the work attachment surface 6s and the external force is transmitted from the rotating body 6 to the base 4, the magnitude of the external force is increased. Accordingly, the base 4 may be elastically deformed. In this case, the rotating body 6 (motor output shaft) supported rotatably with respect to the base 4 is displaced according to the amount of elastic deformation of the base 4. This makes it difficult to maintain high accuracy (for example, parallelism, shake accuracy during rotation, etc.) of the rotating body 6 (motor output shaft), for example.

The contact portion of the bottom surface 4s of the DD motor (base 4) with the fixed surface 2s of the base 2 is only the bottom surface 4s on the outer peripheral side of the base 4, and the bottom surface 4s is separated from the fixed surface 2s toward the center side. Therefore, there is a limit to improving the heat dissipation when driving the DD motor. That is, the heat generated from the DD motor tries to conduct from the bottom surface 4 s of the base 4 to the fixed surface 2 s of the base 2, but the contact portion between the bottom surface 4 s and the fixed surface 2 s is limited to the outer peripheral side of the base 4. Therefore, there is a limit to the amount of heat released from such a contact portion. For this reason, depending on the amount of heat that remains without being released, the temperature of the DD motor may increase, and the drive efficiency of the motor may be thermally affected.
JP 2000-139068 A

  The present invention has been made to solve such problems, and an object of the present invention is to provide a highly rigid direct drive motor installation technique with high accuracy of the motor output shaft and excellent heat dissipation.

  In order to achieve such an object, the present invention provides an annular base that is fixed in a state where the entire bottom surface is abutted against a fixed surface of a base, and is rotatably supported with respect to the base. A rotating body having a work mounting surface that can be mounted, and a motor that is installed between the base and the rotating body and rotates the rotating body in a predetermined direction, and at least a part of the bottom surface of the base is another part. It is a method of installing a direct drive motor having a middle and high shape that protrudes toward the fixed surface of the base, and a positioning step that positions the bottom surface of the base in a state of being applied to the fixed surface of the base, When fixing the base to the base, the base is elastically deformed with a fixing member and the entire bottom surface of the base is pressed against the fixed surface of the base, and the work mounting surface of the rotating body is ground with a grinding member Apply processing And a step grinding is set parallel to the workpiece mounting surface relative to the base of the fixing surface.

  In this invention, the fixing member includes a bolt that can be screwed into the fixing hole formed in the base through the bolt hole formed in the base, and the bolt is fixed from the bolt hole in the press-contact fixing process. By screwing into the hole, the base is elastically deformed and the entire bottom surface of the base is pressed against the fixed surface of the base. In the cutting process, the workpiece mounting surface is cut by bringing the grinding member into sliding contact with the workpiece mounting surface while relatively rotating the rotating body and the grinding member.

  In this case, the grinding member can be formed of a metal material or a non-metal material. The motor includes a stator fixed to the base and a rotor fixed to the rotating body and opposed to the stator with a predetermined gap, and has a projecting bottom surface having a medium-high shape. The amount is set smaller than the gap between the stator and the rotor. In addition, the direct drive motor installed in the base by the installation method mentioned above is included in this invention.

  According to the present invention, it is possible to install a direct drive motor while maintaining high accuracy of the motor output shaft (for example, parallelism, runout accuracy during rotation), and excellent heat dissipation provided by the installation method. A highly rigid direct drive motor can be realized.

  Hereinafter, a direct drive motor according to an embodiment of the present invention will be described with reference to FIG. Since the present embodiment is an improvement of the above-described direct drive motor (FIG. 5), only the improved portion will be described below. In addition, about the structure same as FIG. 5, the same code | symbol is attached | subjected on drawing, and the description is abbreviate | omitted.

  As shown in FIG. 1 (b), in the direct drive motor (hereinafter referred to as a DD motor) of the present embodiment, the bottom 4s of the base 4 is fixed to the base 2 at least partly than the other part. It has a medium-high shape protruding toward the surface 2s. In the configuration example shown in the drawing, as an example of a portion that protrudes in a middle-high shape, a portion on the center side of the bottom surface 4s of the base 4 is protruded more than other portions. Specifically, on the bottom surface 4 s of the base 4, the center portion P <b> 1 on the center side of the base 4 is protruded by a protrusion amount H from the outermost peripheral portion P <b> 2 on the outer periphery side. In this case, the central portion P1 is in the vicinity of the bottom surface side of the hollow hole 4h in the cylindrical portion 4b, and the outermost peripheral portion P2 is the outer periphery on the bottom surface side of the annular fixing portion 4a.

  In such a configuration, when the DD motor is fixed to the base 2, first, the bottom surface 4 s of the base 4 is positioned in a state of being applied to the fixing surface 2 s of the base 2. At this time, the center portion P1 protruding in a middle-high shape is applied to the fixed surface 2s of the base 2, and the outermost peripheral portion P2 is slightly separated from the fixed surface 2s. In this state, when the fixing member (for example, the bolt 10) is screwed into the fixing hole 22 of the base 2 through the bolt hole 20 on the outer peripheral side (fixing portion 4a) of the base 4, this causes the outermost peripheral portion P2 to move. The force which presses the said outermost peripheral part P2 to the fixed surface 2s direction acts on.

  The pressing force acting at this time is transmitted to the central portion P1 applied to the fixed surface 2s and presses the central portion P1 against the fixed surface 2s. However, a reaction force against the pressing force is applied from the fixed surface 2s to the central portion P1. By working, the base 4 is elastically deformed according to the magnitude of the reaction force. As a result, the central portion P1 is recessed (or the outermost peripheral portion P2 is displaced in the direction of the fixed surface 2s), and the bottom surface 4s of the outermost peripheral portion P2 is in pressure contact with the fixed surface 2s.

  In the DD motor of the present embodiment, the base 4 is formed such that the outer peripheral side fixing portion 4a and the center side cylindrical portion 4b are relatively thick, and annularly formed between the fixing portion 4a and the cylindrical portion 4b. The extended connecting portion 4c is formed relatively thin. In this case, the base 4 has a structure in which the range surrounded by the annular connecting portion 4c is easily elastically deformed, and the bottom surface 4s of the center portion P1 in the range protrudes in a middle-high shape. According to such a structure, when the reaction force acts on the central portion P1 as described above, the connecting portion 4c is elastically deformed according to the protruding amount H of the bottom surface 4s having a middle and high shape, thereby the central portion P1. Is depressed (or the outermost peripheral portion P2 is displaced in the direction of the fixed surface 2s), and the bottom surface 4s of the outermost peripheral portion P2 is in pressure contact with the fixed surface 2s.

  As shown in FIG. 1A, the bottom surface 4s of the base 4 is entirely in contact with the fixed surface 2s of the base 2 in a state where the bottom surface 4s of the outermost peripheral portion P2 is pressed against the fixed surface 2s. Adhere closely. By the way, when the DD motor is fixed to the base 2, the base 4 is elastically deformed according to the protruding amount H of the bottom surface 4 s having a medium-high shape, but the deformation amount needs to be absorbed by the internal structure of the DD motor. There is. In other words, when the base 4 is elastically deformed, it is necessary to prevent the internal structures of the DD motors from interfering (contacting) with each other due to the deformation amount (protrusion amount H).

  In this case, since a gap G is formed between the electromagnet (stator) 8a and the permanent magnet (rotor) 8b in the motor 8, the amount of protrusion H of the bottom surface 4s is greater than the gap G between the stator 8a and the rotor 8b. In addition, even if the base 4 is elastically deformed according to the protrusion amount H, the deformation amount can be absorbed by the gap G. Thereby, the internal structure of the DD motor does not interfere (contact) with each other.

  Here, assuming a base 4 projecting from the bottom surface 4s of the central portion P1 to a medium-high shape (FIGS. 1A and 1B), when the projection amount H is specifically quantified, the stator 8a and the rotor 8b When the gap G is set to 100 μm, for example, if the base 4 has an outer diameter φ of 170 mm, the protruding amount H may be set to 10 to 50 μm. Further, if the base 4 has an outer diameter φ of 340 mm, the protrusion amount H may be set to 20 to 100 μm. The DD motor can be stably and firmly fixed to the base 2 without causing the internal structures of the DD motor to interfere (contact) each other.

  At this time, the entire bottom surface 4s of the base 4 is uniformly and stably supported by the fixed surface 2s of the base 2, thereby maintaining high rigidity (for example, axial rigidity and moment rigidity) of the entire DD motor. can do. In this case, for example, even if an external force acts on the work attached to the work attachment surface 6s and the external force is transmitted from the rotating body 6 to the base 4, the base 4 is not elastically deformed. The rotating body 6 (motor output shaft) that is rotatably supported can always be maintained at a certain accuracy (for example, parallelism, shake accuracy during rotation, etc.).

Further, in this state where the DD motor is fixed to the base 2, the entire bottom surface 4 s of the base 4 can be uniformly supported by the fixing surface 2 s of the base 2, so that the base 4 can be thinned. As a result, the DD motor can be reduced in thickness.
Furthermore, since the contact portion of the bottom surface 4s of the DD motor (base 4) with the fixed surface 2s of the base 2 is the entire bottom surface 4s of the base 4, heat generated from the DD motor is transferred from the entire bottom surface 4s of the base 4 to the base. 2 can be efficiently conducted (heat radiation) to the fixed surface 2s. As a result, since the temperature increase of the DD motor can be effectively suppressed, there is no thermal influence on the driving efficiency of the motor.

Further, when the DD motor is fixed to the base 2, the base 4 is elastically deformed, so that the contact pressure between the bolt hole 20 and the bolt 10 can be increased according to the elastic deformation. It is possible to make the bolt 10 screwed into the fixing hole 22 of the table 2 difficult to loosen. As a result, the DD motor can be firmly fixed to the base 2.
Furthermore, since the base 4 with the bottom surface 4s having a medium-high shape is easier to manufacture (for example, machining of the bottom surface 4s) than the base 4 with the bottom surface 4s having a concave shape (FIG. 4), a DD motor The manufacturing cost can be greatly reduced.

By the way, in the state where the DD motor is fixed to the base 2 as described above, for example, depending on the screwing degree and the screwing amount of the bolt 10, or the protruding amount H and the protruding position of the bottom surface 4s of the base 4 having a medium-high shape, There is a case where the work mounting surface 6s of the rotating body 6 is inclined and positioned. For example, the workpiece attachment surface 6s may be positioned to be inclined with respect to the fixed surface 2s of the base 2.
Therefore, in the installation method of the present embodiment, in the DD motor fixed to the base 2, the workpiece mounting surface 6 s of the rotating body 6 is cut by the grinding member 28 and the workpiece mounting surface 6 s is used as the base 2. Is set parallel to the fixed surface 2s.

  Here, as an example of the grinding method, for example, as shown in FIG. 2, the grinding member 28 is rotated while the rotating body 6 and the grinding member 28 are relatively rotated in a state where the DD motor is fixed to the base 2. Can be slid along the workpiece mounting surface 6s, so that the workpiece mounting surface 6s can be shaved. In addition, as the grinding member 28, for example, a commercially available grinder formed of a metal material or a non-metal material may be applied, and therefore, it is not particularly limited here.

  In the example of FIG. 2, the grinding member 28 has a disk shape, and the center thereof is fixed to the rotating shaft 32 of the driving device 30. In this case, the driving device 30 is installed on the fixed surface 2 s of the base 2, and the rotating shaft 32 is slid in the axial direction by the driving device 30, so that the disk-shaped grinding member 28 is moved in the arrow Y direction. Simultaneously with the rotation, it can be translated in the direction of the arrow X. The arrow X direction is a direction extending in parallel along the fixed surface 2 s of the base 2.

  In actual cutting, the rotating body 6 is rotated and the grinding member 28 is also rotated while the grinding member 28 is in contact with the workpiece mounting surface 6s of the rotating body 6 at a predetermined pressure F. At this time, the grinding member 28 comes into sliding contact with the workpiece attachment surface 6s, and the workpiece attachment surface 6s is cut according to the sliding contact pressure F at that time. Then, by moving the grinding member 28 in the direction of the arrow X, the entire workpiece mounting surface 6s can be cut by a predetermined amount. In addition, about the rotation direction of the rotary body 6 and the grinding member 28, since the workpiece attachment surface 6s should just be able to cut efficiently, it does not specifically limit.

  In this case, the amount of cutting of the workpiece attachment surface 6s is arbitrarily set according to the inclination state and the amount of inclination of the workpiece attachment surface 6s, and is not particularly limited here. 2 until it is parallel to the fixed surface 2s. This makes it possible to rotate various workpieces attached to the workpiece attachment surface 6s with high accuracy (for example, parallelism and runout accuracy during rotation).

  Here, an embodiment of a DD motor that has been subjected to the above-described cutting process will be described with reference to FIGS. 4A and 4B, for example. First, FIG. 4A shows a DD motor according to the first embodiment. The DD motor is mounted on the fixed surface 2s of the base 2, and the work attachment of the rotating body 6 is performed. A workpiece W as a workpiece is attached to the surface 6s. And while rotating the workpiece | work W with the rotary body 6, the rotary grinder 24 is pressed with respect to the said workpiece | work W, and the workpiece surface Ws is shaved.

  In the example of FIG. 4A, the pressing force of the grinder 24 acts on the base 4 via the rotating body 6. Even in such a case, the workpiece W is maintained in a state of maintaining high parallelism. Since it can be rotated, the machining accuracy of the workpiece surface Ws by the grinder 24 can be kept constant. As another effect, as in the above-described embodiment, the rigidity (for example, axial rigidity, moment rigidity, etc.) of the entire DD motor can be increased. Further, the accuracy of the rotating body 6 (motor output shaft) can be maintained high, and excellent heat dissipation can be ensured.

  Next, in the second embodiment shown in FIG. 4B, the DD motor is configured to be suspended from the fixed surface 2s of the base 2, and the work mounting surface 6s of the rotating body 6 includes A workpiece transfer structure 26 is attached. In this case, the work transport structure 26 is provided with a plurality of transport arms 26a on the lower end surface thereof. For example, the work transport structure together with the rotating body 6 while holding the spherical work W on the transport arm 26a. By rotating the body 26, the workpiece W can be conveyed in the arrow T direction.

  In the example of FIG. 4B, since the workpiece transfer structure 26 can be rotated while maintaining a high degree of parallelism, the workpiece W held by the transfer arm 26a is moved without being displaced in the vertical direction. It can be transported stably and accurately in the T direction. At this time, the tensile force (gravity) of the workpiece conveying structure 26 and the workpiece W acts on the base 4 via the rotating body 6. Even in such a case, the same as in the above-described embodiment. In addition, the rigidity (for example, axial rigidity, moment rigidity, etc.) of the entire DD motor can be increased. Further, the accuracy of the rotating body 6 (motor output shaft) can be maintained high, and excellent heat dissipation can be ensured.

  In the above-described embodiment and the first and second examples, the base 4 has a structure in which the range surrounded by the annular connecting portion 4c is easily elastically deformed. Although the bottom surface 4s of P1 is protruded into a medium-high shape, the present invention is not limited to this, and a portion and a protrusion amount that are protruded into a medium-high shape according to the type of DD motor, the shape of the base 4, and the thickness change state. H can be set arbitrarily. For example, when the range in which elastic deformation is likely to occur is deviated from the center side of the base 4, the protruding portion may be shifted accordingly. Moreover, when the range which is easy to elastically deform is scattered in several places, you may make it protrude several places according to it.

  Further, when the DD motor is fixed to the base 2, a liquid or gel-like high heat conductive member (for example, silicon grease) is interposed between the fixing surface 2 s of the base 2 and the bottom surface 4 s of the base 4. Also good. By interposing such a high heat conduction member, the heat dissipation of the DD motor can be further improved.

  Further, in the above-described embodiment and the first and second examples, for example, as shown in FIG. 3A, the base 4 has the entire outer diameter of the annular fixing portion 4a as the outer diameter of the motor 8 (motor cover). However, instead of this, for example, as shown in FIG. 3 (b), the other part of the fixing part 4a is removed except for the part fixed by the bolt 10. The base 4 may be configured. With this configuration, it is possible to reduce the material (for example, metal, synthetic resin, etc.) for molding the base 4, and as a result, the DD motor can be reduced in weight and the manufacturing cost can be reduced. be able to.

  Further, in the embodiment described above, the medium-high shape of the bottom surface 4s of the base 4 is not particularly limited. For example, as shown in FIG. 1B, the bottom surface 4s protrudes into a medium-high shape as one continuous conical surface. In addition to the above, a plurality of curved surfaces having different curvatures may be overlapped with each other to protrude the bottom surface 4s into a medium-high shape, or a part of the bottom surface 4s may protrude into a rectangular cross section.

(a) is sectional drawing which shows the structure of the direct drive motor which concerns on one embodiment of this invention, (b) is an assembly drawing of the direct drive motor of the figure (a). It is a figure for demonstrating the installation method of a direct drive motor, Comprising: The figure which shows the state which has given the cutting process to the workpiece | work attachment surface of a rotary body. (a) is a top view of the direct drive motor shown in FIG. 1, (b) is a top view of a direct drive motor according to a modification of the present invention. (a) is a figure which shows 1st Example of the direct drive motor of this invention, (b) is a figure which shows 2nd Example of the direct drive motor of this invention. (a) is sectional drawing which shows the structure of the conventional direct drive motor, (b) is an assembly drawing of the direct drive motor of the figure (a).

Explanation of symbols

2 Base 2s Fixed surface 4 Base 4s Bottom surface 6 Rotating body 6s Work mounting surface 8 Motor 28 Grinding member

Claims (6)

An annular base that is fixed in a state in which the entire bottom surface is applied to the fixed surface of the base, a rotating body that is rotatably supported with respect to the base and has a work mounting surface on which various workpieces can be mounted, and a base And a motor that rotates the rotating body in a predetermined direction, and the bottom surface of the base projects at least part of it toward the fixed surface of the base more than other parts. A method for installing a direct drive motor having a shape,
A positioning step for positioning the bottom surface of the base against the fixed surface of the base;
When fixing the base to the base, a pressure-fixing process in which the base is elastically deformed by a fixing member and the entire bottom surface of the base is pressed against the fixing surface of the base;
A method for installing a direct drive motor, comprising: a step of grinding a workpiece mounting surface of a rotating body with a grinding member to set the workpiece mounting surface parallel to a fixed surface of a base. The fixing member includes a bolt that can be screwed into a fixing hole formed in the base through a bolt hole formed in the base.
2. The press contact fixing step according to claim 1, wherein the base is elastically deformed by screwing the bolt into the fixing hole from the bolt hole, and the entire bottom surface of the base is pressed into contact with the fixed surface of the base. How to install a direct drive motor.   The grinding process is performed on the workpiece mounting surface by causing the grinding member to slide along the workpiece mounting surface while relatively rotating the rotating body and the grinding member. The installation method of the direct drive motor of 1 or 2.   4. The direct drive motor installation method according to claim 1, wherein the grinding member is formed of a metal material or a non-metal material. The motor includes a stator fixed to the base and a rotor fixed to the rotating body and facing the stator with a predetermined gap therebetween,
The method for installing a direct drive motor according to any one of claims 1 to 4, wherein an amount of protrusion of the bottom surface having the middle-high shape is set to be smaller than a gap between the stator and the rotor. The direct drive motor installed in the base by the installation method in any one of Claims 1-5.

Images