JP7460492B2 - stepper motor - Google Patents

Description

The present invention relates to a stepping motor that includes a rotor having a rotating shaft and a driving magnet, and a stator disposed on the outer peripheral side of the driving magnet.

Conventionally, a stepping motor is known that includes a rotor having a rotating shaft and a driving magnet, and a cylindrical stator disposed on the outer peripheral side of the driving magnet (for example, see Patent Document 1). In the stepping motor described in Patent Document 1, the stator includes two inner stator cores and two outer stator cores each having a plurality of pole teeth facing each other on the outer peripheral surface of a driving magnet. A driving coil is wound around the outer periphery of the plurality of pole teeth via a bobbin (winding bobbin). One end of the terminal pin to which the end of the drive coil is connected is attached to the bobbin. The other end of the terminal pin is fixed to a board (terminal board). The substrate is held by a substrate holder.

In the stepping motor described in Patent Document 1, the bobbin has a cylindrical portion arranged on the outer periphery of the multiple pole teeth and a flange portion extending from each end of the cylindrical portion, and the drive coil is wound around the cylindrical portion. The inner stator core and the outer stator core have annular plate portions to which the roots of the pole teeth are connected. The bobbin is arranged between the annular plate portion of the inner stator core and the annular plate portion of the outer stator core in the axial direction of the rotation shaft. One of the two outer stator cores has a motor case that constitutes the outer periphery of the stepping motor. The motor case has a terminal opening. The board holder is fixed to the motor case so as to cover a part of the terminal opening.

Japanese Patent Application Laid-Open No. 10-94214

In the stepping motor described in Patent Document 1, gaps are formed between the inner stator core, the outer stator core, and the bobbin in the axial direction of the rotating shaft, so that the bobbin can move relative to the inner stator core and the outer stator core. When the rotor is rotating, the bobbin may shake against the inner stator core and the outer stator core. Further, if the bobbin rattles against the inner stator core and outer stator core while the rotor is rotating, there is a risk that abnormal noise may be generated or the drive coil may be disconnected.

The objective of the present invention is to provide a stepping motor that can suppress rattling of the bobbin relative to the stator core when the rotor is rotating.

In order to solve the above problems, the stepping motor of the present invention comprises a rotor having a rotating shaft and a driving magnet, a stator having a driving coil and arranged on the outer periphery of the driving magnet, a terminal pin to which an end of the driving coil is electrically connected, a substrate to which the terminal pin is fixed, and a substrate holder for holding the substrate, the stator comprises a stator core having a plurality of pole teeth arranged opposite the outer periphery of the driving magnet, a bobbin having a cylindrical portion arranged on the outer periphery of the plurality of pole teeth and a flange portion extending from each end of the cylindrical portion in a flange-like shape, and a driving coil wound around the outer periphery of the cylindrical portion, and the substrate holder comprises a bobbin pressing portion that presses the bobbin to one side in the axial direction of the rotating shaft and presses one of the two flange portions against the stator core, and contact portions that contact the stator core or a fixed member fixed to the stator core at a predetermined contact pressure in the axial direction of the rotating shaft on both sides of the axial direction of the rotating shaft.

In the stepping motor of the present invention, the contact portions of the substrate holder are in contact with the stator core or a fixed member fixed to the stator core on both sides of the axial direction of the rotating shaft at a predetermined contact pressure in the axial direction of the rotating shaft. Therefore, in the present invention, it is possible to prevent the substrate holder from moving relative to the stator core in the axial direction of the rotating shaft. Furthermore, in the present invention, the bobbin pressing portion of the substrate holder presses the bobbin to one side in the axial direction of the rotating shaft and presses one of the two flanges against the stator core, so it is possible to prevent the bobbin from moving relative to the stator core in the axial direction of the rotating shaft. Therefore, in the present invention, it is possible to suppress rattling of the bobbin against the stator core when the rotor is rotating.

In the present invention, for example, the stator core has a flat, annular plate portion to which the roots of the multiple pole teeth are connected, the stator has two bobbins and two drive coils arranged in the axial direction of the rotating shaft, and the stator core has two inner stator cores whose annular plate portions are arranged between the two drive coils in the axial direction of the rotating shaft, and two outer stator cores whose annular plate portions are arranged outside the two drive coils in the axial direction of the rotating shaft, and the substrate holder has, as bobbin pressing portions, a first bobbin pressing portion that presses the flange portion of one of the two bobbins against the annular plate portion of one of the two inner stator cores, and a second bobbin pressing portion that presses the flange portion of the other of the two bobbins against the annular plate portion of the other of the two inner stator cores.

In the present invention, for example, the bobbin has a terminal holding portion that holds a terminal pin, the outer stator core has a cylindrical case portion that covers the outer peripheral surface of the drive coil, one end of the case portion is connected to the annular plate portion, the other ends of the case portions of the two outer stator cores are fixed to each other with the other ends of the case portions of the two outer stator cores in contact with each other, an opening is formed in the two case portions that are fixed to each other for arranging the terminal holding portion, and the board holder covers a part of the opening.

Here, in the axial direction of the rotating shaft, the annular plate of the inner stator core and the flange of the bobbin are brought into contact with a predetermined contact pressure, and the annular plate of the outer stator core and the flange of the bobbin are brought into contact with a predetermined contact pressure. By bringing the bobbin into contact with the bobbin, it is possible to suppress the wobbling of the bobbin with respect to the stator core while the rotor is rotating. However, in a stepping motor in which the other ends of the case parts of the two outer stator cores are in contact with each other and the other ends of the two case parts are fixed to each other, the annular plate part of the inner stator core and the flange part of the bobbin are When the annular plate portion of the outer stator core and the flange portion of the bobbin are in contact with each other with a predetermined contact pressure, when the other ends of the two case portions are fixed to each other, There is a possibility that a force in the direction of separating the case parts from each other may act on the outer stator core. Therefore, in this case, the other ends of the two case parts are fixed to each other while applying force to the outer stator core in the axial direction of the rotating shaft so that the other ends of the two case parts come into contact with each other. In some cases, the other ends of the two case parts may have to be fixed to each other, and the work to fix them to each other may become complicated.

In contrast, in the present invention, even if the annular plate portion of the outer stator core and the flange portion of the bobbin are not in contact with each other, it is possible to suppress rattling of the bobbin against the stator core when the rotor is rotating, so there is no need to make the annular plate portion of the outer stator core and the flange portion of the bobbin come into contact with each other. Therefore, in the present invention, by attaching the board holder after fixing the other ends of the two case parts to each other, it is possible to fix the other ends of the two case parts to each other without a force acting on the outer stator core in a direction that moves the two case parts away from each other. In other words, by attaching the board holder after fixing the other ends of the two case parts to each other, it is possible to fix the other ends of the two case parts to each other without applying a force to the outer stator core in the axial direction of the rotation shaft, and as a result, it is possible to easily perform the work of fixing the other ends of the two case parts to each other.

In the present invention, the stepping motor includes, for example, a first fixed member fixed to one end face of the stator in the axial direction of the rotating shaft, and a second fixed member fixed to the other end face of the stator in the axial direction of the rotating shaft, and the substrate holder includes, as contact portions, a first contact portion that contacts the first fixed member, and a second contact portion that contacts the second fixed member.

In the present invention, the bobbin pressing portion, for example, contacts the other of the two flanges and presses the other of the two flanges. According to studies by the inventors of the present application, in this case, it becomes easier to suppress rattling of the bobbin with respect to the stator core while the rotor is rotating.

In the present invention, the substrate holder includes one first bobbin pressing section, one second bobbin pressing section, and is arranged on both sides of the first bobbin pressing section in an orthogonal direction perpendicular to the axial direction of the rotating shaft. It is preferable to include two first contact parts and two second contact parts arranged on both sides of the second bobbin pressing part in the orthogonal direction. With this configuration, it becomes possible to stabilize the attachment state of the board holder to the stator core.

In the present invention, the bobbin pressing portion may contact the terminal holding portion and press the terminal holding portion.

In the present invention, it is preferable that the substrate holder includes third contact portions that contact the stator core in the orthogonal direction with a predetermined contact pressure on both sides in the orthogonal direction orthogonal to the axial direction of the rotating shaft. With this configuration, it becomes possible to stabilize the attachment state of the board holder to the stator core.

Further, in order to solve the above problems, a stepping motor of the present invention includes a rotor having a rotating shaft and a driving magnet, a stator having a driving coil and disposed on the outer circumferential side of the driving magnet, and a driving coil. The stator includes a terminal pin to which an end is electrically connected, a substrate to which the terminal pin is fixed, and a substrate holder that holds the substrate. a stator core having a stator core, two bobbins having a cylindrical part disposed on the outer peripheral side of a plurality of pole teeth, and a flange extending from each end of the cylindrical part in a flange shape, The two bobbins and the two driving coils are arranged in the axial direction of the rotating shaft, and the substrate holder is arranged in the axial direction of the rotating shaft. A bobbin pressing part that presses two bobbins together by pushing the bobbins in a direction in which the two bobbins approach each other contacts the stator core or a fixed member fixed to the stator core on both sides in the axial direction of the rotating shaft with a predetermined contact pressure in the axial direction of the rotating shaft. It is characterized by comprising a contact portion.

In the stepping motor of the present invention, the contact portion of the substrate holder is in contact with the stator core or a fixed member fixed to the stator core on both sides of the axial direction of the rotating shaft at a predetermined contact pressure in the axial direction of the rotating shaft. Therefore, in the present invention, it is possible to prevent the substrate holder from moving relative to the stator core in the axial direction of the rotating shaft. Also, in the present invention, the bobbin pressing portion of the substrate holder presses the two bobbins in a direction in which the two bobbins approach each other in the axial direction of the rotating shaft, thereby pressing the two bobbins against each other, so that it is possible to prevent the two bobbins from moving relative to the substrate holder in the axial direction of the rotating shaft. Therefore, in the present invention, it is possible to prevent the two bobbins from moving relative to the stator core in the axial direction of the rotating shaft, and as a result, it is possible to suppress rattling of the bobbins relative to the stator core when the rotor is rotating.

Furthermore, in order to solve the above problems, the stepping motor of the present invention includes a rotor having a rotating shaft and a driving magnet, a stator having a driving coil and disposed on the outer circumferential side of the driving magnet, and a driving coil. The stator includes a terminal pin to which an end is electrically connected, a substrate to which the terminal pin is fixed, and a substrate holder that holds the substrate. a stator core having a stator core, a bobbin having a cylindrical portion disposed on the outer peripheral side of the plurality of pole teeth, a flange extending from each end of the cylindrical portion in a flange shape, and a bobbin wound around the outer peripheral surface of the cylindrical portion. The board holder includes a bobbin pressing part that presses the bobbin by contacting the bobbin with a predetermined contact pressure from both sides in the axial direction of the rotating shaft, and a stator core or a bobbin pressing part that presses the bobbin on both sides in the axial direction of the rotating shaft. It is characterized by comprising a contact portion that contacts the fixed member with a predetermined contact pressure in the axial direction of the rotating shaft.

In the stepping motor of the present invention, the contact portion of the substrate holder is in contact with the stator core or a fixed member fixed to the stator core on both sides in the axial direction of the rotating shaft with a predetermined contact pressure in the axial direction of the rotating shaft. Therefore, in the present invention, it is possible to prevent the substrate holder from moving relative to the stator core in the axial direction of the rotating shaft. Furthermore, in the present invention, the bobbin pressing portion of the substrate holder contacts the bobbin with a predetermined contact pressure from both sides in the axial direction of the rotating shaft and presses the bobbin, so that the bobbin is prevented from moving relative to the substrate holder. becomes possible. Therefore, in the present invention, it is possible to prevent the bobbin from moving relative to the stator core in the axial direction of the rotating shaft, and as a result, the wobbling of the bobbin relative to the stator core while the rotor is rotating is suppressed. It becomes possible to do so.

As described above, in the stepping motor of the present invention, it is possible to suppress rattling of the bobbin relative to the stator core when the rotor is rotating.

1 is a side view of a stepping motor according to an embodiment of the present invention. 2 is a sectional view of section E in FIG. 1. FIG. 2 is a plan view of part E in FIG. 1 with the substrate and substrate holder removed. FIG. 2 is a cross-sectional view taken along the line FF in FIG. 1. (A) is a perspective view showing the substrate holder shown in FIG. 1 from the bottom side, and (B) is a bottom view of the substrate holder shown in FIG. 1.

Embodiments of the present invention will be described below with reference to the drawings.

(Overall configuration of stepping motor)
FIG. 1 is a side view of a stepping motor 1 according to an embodiment of the invention. FIG. 2 is a sectional view of section E in FIG.

The stepping motor 1 (hereinafter referred to as "motor 1") of this embodiment includes a rotor 4 having a rotating shaft 2 and a drive magnet 3, and a stator 7 having drive coils 5, 6 and arranged on the outer periphery of the drive magnet 3. In the following description, the X direction in FIG. 1, etc., which is the axial direction of the rotating shaft 2, is defined as the front-rear direction, the X1 direction in FIG. 1, etc., which is one side of the front-rear direction, is defined as the "front" side, and the X2 direction in FIG. 1, etc., which is the other side of the front-rear direction, is defined as the "rear" side. In this embodiment, the front side (X1 direction side) is the output side of the rotating shaft 2, and the rear side (X2 direction side) is the anti-output side of the rotating shaft 2.

For ease of explanation, the Y direction in Fig. 1 etc., which is perpendicular to the front-rear direction, is defined as the left-right direction, and the Z direction in Fig. 1 etc., which is perpendicular to the front-rear direction and the left-right direction, is defined as the up-down direction. The Z1 direction in Fig. 1 etc., which is one side of the up-down direction, is defined as the "up" side, and the Z2 direction in Fig. 1 etc., which is the other side of the up-down direction, is defined as the "down" side. The left-right direction (Y direction) in this embodiment is an orthogonal direction that is perpendicular to the axial direction of the rotation shaft 2.

The motor 1 includes, in addition to the rotor 4 and the stator 7, a frame 8 fixed to the front end surface of the stator 7, an end plate 9 fixed to the rear end surface of the stator 7, and an output side end ( a bearing 10 that supports the front end (front end), a bearing 11 that supports the opposite end (rear end) of the rotating shaft 2, and a terminal pin to which the ends of the drive coils 5 and 6 are electrically connected. 12, a substrate 13 to which the terminal pins 12 are fixed, and a substrate holder 14 that holds the substrate 13.

The majority of the output side of the rotating shaft 2 protrudes forward from the stator 7. The part of the rotating shaft 2 that protrudes forward from the stator 7 is a feed screw shaft (lead screw) 2a with a feed screw formed on its outer circumferential surface. A cylindrical bush 16 is fixed to the outer circumferential surface of the rotating shaft 2. The bush 16 is disposed rearward from the feed screw shaft 2a. The drive magnet 3 is formed in a cylindrical shape. The inner circumferential surface of the drive magnet 3 is fixed to the outer circumferential surface of the bush 16 by adhesive, and the drive magnet 3 is disposed rearward from the feed screw shaft 2a.

The stator 7 has a generally cylindrical shape as a whole. The front end surface and the rear end surface of the stator 7 are annular planes perpendicular to the front-rear direction. In addition to the drive coils 5 and 6, the stator 7 includes stator cores 18 to 21 in which a plurality of pole teeth 17 are formed to face each other on the outer peripheral surface of the drive magnet 3, and the stator cores 18 to 21 and the drive coil 5. , 6. The specific configuration of the stator 7 will be described later.

The frame 8 is formed into a rectangular groove shape and is composed of a bottom surface portion 8a, a side surface portion 8b rising at a right angle from the front end of the bottom surface portion 8a, and a side surface portion 8c rising at a right angle from the rear end of the bottom surface portion 8a. There is. A side surface portion 8c is fixed to the front end surface of the stator 7. The side surface portion 8c is fixed to the front end surface of the stator 7 by, for example, welding. A through hole through which the rotating shaft 2 is inserted is formed in the side surface portion 8c. The end plate 9 is formed into a flat plate shape. The end plate 9 is fixed to the rear end surface of the stator 7 so that the thickness direction of the end plate 9 and the axial direction coincide with each other. The end plate 9 is fixed to the rear end surface of the stator 7 by, for example, welding. The bearing 10 is held by the side surface portion 8b. The bearing 11 is held by the end plate 9.

(Stator configuration)
FIG. 3 is a plan view of section E in FIG. 1 with the substrate 13 and substrate holder 14 removed. FIG. 4 is a cross-sectional view taken along the line FF in FIG.

The stator 7 includes two drive coils 5 and 6 and two bobbins 22 and 23. The two drive coils 5 and 6 are spaced apart from each other in the front-rear direction, and the two bobbins 22 and 23 are also spaced apart from each other in the front-rear direction. That is, the two drive coils 5 and 6 and the two bobbins 22 and 23 are arranged in the front-back direction. The drive coil 5 is arranged in front of the drive coil 6. The driving coil 5 is wound around the bobbin 22, and the driving coil 6 is wound around the bobbin 23. That is, the bobbin 22 is disposed in front of the bobbin 23.

Further, the stator 7 includes four stator cores 18 to 21. The stator cores 18 to 21 each include annular plate portions 18a to 21a that are flat and annular to which the roots of the plurality of pole teeth 17 are connected. The annular plate portions 18a to 21a are formed in a substantially annular shape. The annular plate portions 18a to 21a are arranged such that the thickness direction of the annular plate portions 18a to 21a coincides with the front-rear direction. The roots of the plurality of pole teeth 17 are connected to the inner peripheral ends of the annular plate portions 18a to 21a.

The annular plate portion 18a of the stator core 18 and the annular plate portion 19a of the stator core 19 are disposed between the two drive coils 5, 6 in the front-rear direction. The annular plate portion 20a of the stator core 20 is disposed forward of the drive coil 5, and the annular plate portion 21a of the stator core 21 is disposed rearward of the drive coil 6. In other words, the annular plate portions 20a, 21a are disposed outside the two drive coils 5, 6 in the front-rear direction. In this embodiment, the stator cores 18, 19 are inner stator cores, and the stator cores 20, 21 are outer stator cores.

The stator core 18 is disposed in front of the stator core 19. In the stator core 18, a plurality of pole teeth 17 rise from the inner circumferential end of the annular plate portion 18a toward the front side. In the stator core 19, a plurality of pole teeth 17 rise from the inner circumferential end of the annular plate portion 19a toward the rear side. The rear surface of the annular plate portion 18a and the front surface of the annular plate portion 19a are in contact with each other with a predetermined contact pressure. In the stator core 20, a plurality of pole teeth 17 rise from the inner circumferential end of the annular plate portion 20a toward the rear side. In the stator core 21, a plurality of pole teeth 17 rise from the inner circumferential end of the annular plate portion 21a toward the front side.

The pole teeth 17 of the stator core 18 and the pole teeth 17 of the stator core 20 are arranged to face each other on the outer peripheral surface of the front side portion of the driving magnet 3 and are arranged alternately in the circumferential direction of the rotating shaft 2 . The pole teeth 17 of the stator core 19 and the pole teeth 17 of the stator core 21 are arranged opposite to each other on the outer peripheral surface of the rear side portion of the driving magnet 3 and are arranged alternately in the circumferential direction of the rotating shaft 2 .

The front surface of the annular plate portion 20a constitutes the front end surface of the stator 7, and the rear surface of the annular plate portion 21a constitutes the rear end surface of the stator 7. The frame 8 is fixed to the front surface of the annular plate portion 20a. Specifically, the side surface portion 8c is fixed to the front surface of the annular plate portion 20a. The end plate 9 is fixed to the rear surface of the annular plate portion 21a. The frame 8 and the end plate 9 in this embodiment are fixed members fixed to the stator cores 20 and 21. In addition, the frame 8 in this embodiment is a first fixed member fixed to one end surface of the stator 7 in the axial direction of the rotating shaft 2, and the end plate 9 is a second fixed member fixed to the other end surface of the stator 7 in the axial direction of the rotating shaft 2.

The stator core 20 includes a cylindrical case portion 20b that covers the outer peripheral surface of the drive coil 5. Case portion 20b is formed in a cylindrical shape. A front end of the case portion 20b, which is one end of the case portion 20b, is connected to the annular plate portion 20a. Specifically, the front end of the case portion 20b is connected to the outer peripheral end of the annular plate portion 20a. Similar to the stator core 20, the stator core 21 includes a cylindrical case portion 21b that covers the outer peripheral surface of the drive coil 6. The case portion 21b is formed in a cylindrical shape. A rear end of the case portion 21b, which is one end of the case portion 21b, is connected to the annular plate portion 21a. Specifically, the front end of the case portion 21b is connected to the outer peripheral end of the annular plate portion 21a.

Most of the annular plate portion 18a of the stator core 18, excluding the upper and lower ends, is disposed on the inner peripheral side of the case portion 20b. The annular plate portion 18a is press-fitted into the inner peripheral side of the case portion 20b and is fixed to the case portion 20b. Most of the annular plate portion 19a of the stator core 19, excluding the upper and lower ends, is disposed on the inner peripheral side of the case portion 21b. The annular plate portion 19a is press-fitted into the inner peripheral side of the case portion 21b and is fixed to the case portion 21b.

The rear end of the case part 20b, which is the other end of the case part 20b, and the front end of the case part 21b, which is the other end of the case part 21b, are in contact with each other. fixed to each other. In this embodiment, the rear end of case portion 20b and the front end of case portion 21b are fixed to each other by welding. Welding for fixing the rear end of the case part 20b and the front end of the case part 21b is performed at a plurality of locations in the circumferential direction of the rotating shaft 2.

The two case parts 20b and 21b fixed to each other have openings 26 for arranging terminal holding parts 22d and 23d, which will be described later, formed on the bobbins 22 and 23. Specifically, an opening 26 is formed at the upper end of the two case parts 20b and 21b that are fixed to each other. The opening 26 includes a notch 20c formed at the upper end of the case portion 20b and a notch 21c formed at the upper end of the case 21b. The notch portion 20c is formed over the entire area of the case portion 20b in the front-rear direction, and the notch portion 21c is formed over the entire area of the case portion 21b in the front-rear direction. That is, the opening 26 is formed over the entire area of the stator 7 in the front-rear direction. Further, the opening 26 is formed in a rectangular shape.

3 and 4, end face 20d of case part 20b that forms the edge of opening 26 on one side in the left-right direction (specifically, the edge of notch 20c) and end face 21d of case part 21b that forms the edge of opening 26 on one side in the left-right direction (specifically, the edge of notch 21c) are planes perpendicular to the left-right direction. Also, end face 20e of case part 20b that forms the edge of opening 26 on the other side in the left-right direction (specifically, the edge of notch 20c) and end face 21e of case part 21b that forms the edge of opening 26 on the other side in the left-right direction (specifically, the edge of notch 21c) are planes perpendicular to the left-right direction.

The bobbin 22 has a cylindrical shape with a flange, which has a cylindrical portion 22a disposed on the outer peripheral side of the plurality of pole teeth 17, and flange portions 22b and 22c that extend from both ends of the cylindrical portion 22a in a flange shape. It is formed. The bobbin 22 is arranged between the annular plate portion 18a and the annular plate portion 20a in the front-rear direction. That is, the cylindrical portion 22a is arranged on the outer peripheral side of the plurality of pole teeth 17 of the stator cores 18 and 20. The collar portions 22b and 22c are formed in an annular shape that extends outward in the radial direction of the rotating shaft 2 from each of both ends of the cylindrical portion 22a. The flange portion 22b is connected to the front end of the cylindrical portion 22a, and the flange portion 22c is connected to the rear end of the cylindrical portion 22a. The drive coil 5 is wound around the outer peripheral surface of the cylindrical portion 22a.

Like the bobbin 22, the bobbin 23 has a cylindrical cylindrical portion 23a disposed on the outer peripheral side of the plurality of pole teeth 17, and flanges 23b and 23c that extend in a flange shape from both ends of the cylindrical portion 23a. It is formed into a cylindrical shape with a flange. The bobbin 23 is disposed between the annular plate portion 19a and the annular plate portion 21a in the front-rear direction. That is, the cylindrical portion 23a is arranged on the outer peripheral side of the plurality of pole teeth 17 of the stator cores 19 and 21. The collar portions 23b and 23c are formed in an annular shape that extends outward in the radial direction of the rotating shaft 2 from each of both ends of the cylindrical portion 23a. The flange portion 23b is connected to the rear end of the cylindrical portion 23a, and the flange portion 23c is connected to the front end of the cylindrical portion 23a. The drive coil 6 is wound around the outer peripheral surface of the cylindrical portion 23a.

The bobbins 22 and 23 are provided with terminal holding portions (terminal blocks) 22d and 23d that hold the terminal pins 12. The terminal holding portion 22d protrudes upward from the flange portion 22c, and the terminal holding portion 23d protrudes upward from the flange portion 22d. The terminal holding portions 22d and 23d are disposed adjacent to each other in the front-to-rear direction. A gap is formed between the terminal holding portions 22d and 23d in the front-to-rear direction. The front surface of the terminal holding portion 22d and the rear surface of the terminal holding portion 23d are flat surfaces that are perpendicular to the front-to-rear direction. The lower ends of the terminal holding portions 22d and 23d are disposed in the opening 26.

The terminal holding parts 22d and 23d hold the lower ends of the plurality of terminal pins 12. The substrate 13 is a flat rigid substrate. The substrate 13 is arranged so that the thickness direction of the substrate 13 and the vertical direction coincide with each other. The upper ends of the terminal pins 12 are fixed to the substrate 13, and the substrate 13 is arranged above the terminal holding parts 22d and 23d. Note that a connector (not shown) is mounted on the upper surface of the board 13.

(Substrate holder configuration)
5(A) is a perspective view showing the substrate holder 14 shown in FIG. 1 from the bottom side, and FIG. 5(B) is a bottom view of the substrate holder 14 shown in FIG. 1.

The substrate holder 14 is made of resin. Specifically, the substrate holder 14 is made of resin with relatively high toughness. For example, the substrate holder 14 is made of nylon or the like. The substrate 13 is held on the upper surface side of the substrate holder 14. The upper surface of the substrate holder 14 serves as a substrate holding section 14a that holds the substrate 13. A through hole 14b in which a portion of the terminal pin 12 is disposed is formed in the substrate holding portion 14a. The through hole 14b passes through the substrate holding portion 14a in the vertical direction. The substrate holder 14 is attached to the stator 7 from above. The substrate holder 14 partially closes the opening 26.

The board holder 14 includes bobbin pressing parts 14c and 14d that push the bobbins 22 and 23 to one side in the front-rear direction and press the flanges 22c and 23c against the stator cores 18 and 19. Specifically, the board holder 14 includes a bobbin pressing portion 14c that presses the collar portion 22c of the bobbin 22 against the annular plate portion 18a of the stator core 18, and a bobbin pressing portion that presses the collar portion 23c of the bobbin 23 against the annular plate portion 19a of the stator core 19. 14d. Further, the substrate holder 14 includes one bobbin pressing portion 14c and one bobbin pressing portion 14d. The bobbin pressing section 14c of this embodiment is a first bobbin pressing section, and the bobbin pressing section 14d is a second bobbin pressing section.

The bobbin pressing parts 14c and 14d are flat projections that protrude downward from the substrate holding part 14a. The bobbin pressing parts 14c and 14d are arranged so that the thickness direction of the bobbin pressing parts 14c and 14d coincides with the front-rear direction, and are slightly elastically deformable in the front-rear direction. The bobbin pressing part 14c is formed forward of the through hole 14b. The bobbin pressing part 14d is formed rearward of the through hole 14b. The bobbin pressing parts 14c and 14d are also formed at the center position of the substrate holder 14 in the left-right direction.

The bobbin pressing portion 14c contacts the flange portion 22b of the bobbin 22 and presses the flange portion 22b. Specifically, the bobbin pressing portion 14c contacts the upper end portion of the flange portion 22b from the front side and presses the flange portion 22b toward the rear side. The flange portion 22c contacts the front surface of the annular plate portion 18a with a predetermined contact pressure. A gap is formed between the flange portion 22b and the annular plate portion 20a in the front-rear direction. The bobbin pressing portion 14d contacts the flange portion 23b of the bobbin 23 and presses the flange portion 23b. Specifically, the bobbin pressing portion 14d contacts the upper end portion of the flange portion 23b from the rear side and presses the flange portion 23b toward the front side. The flange portion 23c contacts the front surface of the annular plate portion 19a with a predetermined contact pressure. In the front-rear direction, a gap is formed between the flange portion 23b and the annular plate portion 21a.

The substrate holder 14 also has contact portions 14e, 14f on both sides in the front-rear direction that contact the frame 8 and the end plate 9 with a predetermined contact pressure in the front-rear direction. Specifically, the substrate holder 14 has a contact portion 14e that contacts the frame 8 from the rear side with a predetermined contact pressure, and a contact portion 14f that contacts the end plate 9 from the front side with a predetermined contact pressure. The substrate holder 14 also has two contact portions 14e and two contact portions 14f. In this embodiment, the contact portion 14e is the first contact portion, and the contact portion 14f is the second contact portion.

The contact portions 14e and 14f are plate-shaped projections that protrude downward from the substrate holding portion 14a. The contact portions 14e, 14f are arranged so that the thickness direction of the contact portions 14e, 14f coincides with the front-rear direction, and can be slightly elastically deformed in the front-rear direction. The contact portion 14e is formed on the front side of the through hole 14b. The contact portion 14f is formed on the rear side of the through hole 14b. The two contact portions 14e are arranged on both sides of the bobbin pressing portion 14c in the left-right direction. The two contact portions 14f are arranged on both sides of the bobbin pressing portion 14d in the left-right direction.

The contact portion 14e contacts the rear surface of the side surface portion 8c of the frame 8 from the rear side. Specifically, a convex portion 14g formed on the front side of the contact portion 14e contacts the rear surface of the side surface portion 8c from the rear side with a predetermined contact pressure. The convex portion 14g slightly protrudes toward the front side. Further, the convex portion 14g is formed in a straight line whose longitudinal direction is the vertical direction. The shape of the convex portion 14g when viewed from above and below is hemispherical. The contact portion 14f contacts the front surface of the end plate 9 from the front side. Specifically, a convex portion 14g formed on the rear surface side of the contact portion 14f contacts the front surface of the end plate 9 from the front side with a predetermined contact pressure. A convex portion 14g formed on the contact portion 14f slightly protrudes toward the rear side.

Furthermore, the substrate holder 14 has contact portions 14h to 14k on both sides in the left-right direction that contact the stator cores 20, 21 with a predetermined contact pressure in the left-right direction. Specifically, the substrate holder 14 has a contact portion 14h on one side in the left-right direction that contacts the stator core 20 from the other side in the left-right direction with a predetermined contact pressure, a contact portion 14i on the other side in the left-right direction that contacts the stator core 20 from one side in the left-right direction with a predetermined contact pressure, a contact portion 14j on one side in the left-right direction that contacts the stator core 21 from the other side in the left-right direction with a predetermined contact pressure, and a contact portion 14k on the other side in the left-right direction that contacts the stator core 21 from one side in the left-right direction with a predetermined contact pressure.

The contact portions 14h to 14k are plate-shaped protrusions that protrude downward from the substrate holding portion 14a. The contact parts 14h to 14k are arranged so that the thickness direction of the contact parts 14h to 14k coincides with the left-right direction, and can be slightly elastically deformed in the left-right direction. The contact portions 14h and 14i are formed on the front side of the through hole 14b. The contact portions 14j and 14k are formed on the rear side of the through hole 14b. Further, the contact portions 14h and 14j are formed on one end side of the substrate holder 14 in the left-right direction, and the contact portions 14i and 14k are formed on one end side of the substrate holder 14 in the left-right direction.

The contact portion 14h contacts the end face 20d of the case portion 20b from the other side in the left-right direction, and the contact portion 14i contacts the end face 20e of the case portion 20b from one side in the left-right direction. Specifically, the convex portion 14p formed on the outer side in the left-right direction of the contact portions 14h and 14i contacts the end faces 20d and 20e with a predetermined contact pressure. The convex portion 14p protrudes slightly outward in the left-right direction. The convex portion 14p is formed in a straight line with the vertical direction as the longitudinal direction. When viewed from the vertical direction, the shape of the convex portion 14p is hemispherical.

Contact portion 14j contacts end face 21d of case portion 21b from the other side in the left-right direction, and contact portion 14k contacts end face 21e of case portion 21b from one side in the left-right direction. Specifically, protrusions 14p formed on the outer sides of contact portions 14j and 14k in the left-right direction contact end faces 21d and 21e with a predetermined contact pressure.

The board holder 14 is attached to the stator 7 with the frame 8 and end plates 9 fixed by being press-fitted from above into the stator 7 with the frame 8 and end plates 9 fixed. Note that the substrate holder 14 includes an engaging claw portion 14r that engages with a through hole formed at the upper end of the end plate 9. As shown in FIG. 2, the engaging claw portion 14r engages with the through hole of the end plate 9 from the rear side, and functions to prevent the substrate holder 14 from coming off upward or forward.

(Main effects of this form)
As explained above, in this embodiment, the contact portion 14e of the substrate holder 14 contacts the side surface portion 8c of the frame 8 fixed to the stator core 20 from the rear side with a predetermined contact pressure, and the contact portion 14f of the substrate holder 14 is in contact with the end plate 9 fixed to the stator core 21 from the front side with a predetermined contact pressure. Therefore, in this embodiment, it is possible to prevent the substrate holder 14 from moving relative to the stator cores 18 to 21 in the front-rear direction.

Moreover, in this embodiment, the bobbin pressing part 14c of the board holder 14 pushes the flange part 22b of the bobbin 22 to the rear side and presses the flange part 22c against the annular plate part 18a of the stator core 18, and the bobbin pressing part 14d of the board holder 14 pushes the flange 23b of the bobbin 23 forward and presses the flange 23c against the annular plate 19a of the stator core 19. Therefore, in this embodiment, it is possible to prevent the bobbins 22 and 23 from moving relative to the stator cores 18 to 21 in the front-rear direction. Therefore, in this embodiment, it is possible to suppress rattling of the bobbins 22 and 23 with respect to the stator cores 18 to 21 when the rotor 4 is rotating.

Here, in the front-back direction, the annular plate part 20a and the flange part 22b are brought into contact with each other with a predetermined contact pressure, and the annular plate part 18a and the flange part 22c are brought into contact with each other with a predetermined contact pressure, and the annular plate part 21a is brought into contact with each other with a predetermined contact pressure. By bringing the annular plate part 19a into contact with the flange part 23b at a predetermined contact pressure, and by bringing the annular plate part 19a and the flange part 23c into contact with a predetermined contact pressure, the stator cores 18 to 21 can be It is possible to suppress rattling of the bobbins 22 and 23.

However, in this case, when the rear end of case portion 20b and the front end of case portion 21b are fixed to each other, a force in a direction that moves case portion 20b and case portion 21b away from each other may act on stator cores 20, 21. Therefore, in this case, it may be necessary to fix the rear end of case portion 20b and the front end of case portion 21b while applying a force in the front-rear direction to stator cores 20, 21 so that the rear end of case portion 20b and the front end of case portion 21b come into contact with each other, which may make the work of fixing the rear end of case portion 20b and the front end of case portion 21b complicated.

In contrast, in this embodiment, even if it is possible to suppress the wobbling of the bobbins 22 and 23 with respect to the stator cores 18 to 21 when the rotor 4 is rotating, the annular plate portion 20a A gap is formed between the annular plate portion 21a and the flange portion 22b, and between the annular plate portion 21a and the flange portion 23b. Furthermore, in this embodiment, since the substrate holder 14 is attached to the stator 7 after the stator 7 is assembled, no force is applied to the stator cores 20 and 21 in the direction of separating the case portion 20b and the case portion 21b from each other. , it becomes possible to fix the rear end of the case part 20b and the front end of the case part 21b. That is, in this embodiment, it is possible to fix the rear end of case portion 20b and the front end of case portion 21b without applying force in the front-rear direction to stator cores 20 and 21. As a result, in this embodiment, it becomes possible to easily perform the work of fixing the rear end of case portion 20b and the front end of case portion 21b.

In this embodiment, two contact parts 14e are arranged on both sides of the bobbin pressing part 14c in the left-right direction, and two contact parts 14f are arranged on both sides of the bobbin pressing part 14d in the left-right direction. Therefore, in this embodiment, it is possible to stabilize the attachment state of the substrate holder 14 to the stator cores 18 to 21.

Further, in this embodiment, the contact portion 14h contacts the end surface 20d of the case portion 20b from the other side in the left-right direction, the contact portion 14i contacts the end surface 20e of the case portion 20b from one side in the left-right direction, and the contact portion 14j contacts the end surface 21d of the case portion 21b from the other side in the left-right direction, and the contact portion 14k contacts the end surface 21e of the case portion 21b from one side in the left-right direction. 14 can be more stable.

(Other embodiments)
Although the embodiment described above is an example of a preferred embodiment of the present invention, it is not limited thereto, and various modifications can be made without changing the gist of the present invention.

In the embodiment described above, the annular plate portion 18a of the stator core 18 may be arranged behind the annular plate portion 19a of the stator core 19. In this case, the front surface of the annular plate portion 18a and the rear surface of the annular plate portion 19a are in contact with each other with a predetermined contact pressure. Further, in this case, the pole teeth 17 of the stator core 18 and the pole teeth 17 of the stator core 19 are arranged at positions where they do not interfere with each other in the circumferential direction of the rotating shaft 2. In this case, the bobbin pressing section 14c presses the collar 22c of the bobbin 22 against the annular plate 19a, and the bobbin pressing section 14d presses the collar 23c of the bobbin 23 against the annular plate 18a.

In the embodiment described above, the board holder 14 may include a bobbin pressing part that contacts the terminal holding part 22d from the front side and pushing the terminal holding part 22d to the rear side, instead of the bobbin pressing part 14c. This bobbin pressing portion presses the collar portion 22c against the annular plate portion 18a by pressing the terminal holding portion 22d. Moreover, in this case, it is preferable that the bobbin pressing part presses a part of the terminal holding part 22d that is away from the terminal pin 12. For example, it is preferable that the bobbin pressing section presses both ends of the terminal holding section 22d in the left and right direction.

In addition, in the above-described embodiment, the board holder 14 may be provided with a bobbin pressing portion, instead of the bobbin pressing portion 14d, that contacts the terminal holding portion 23d from the rear side and presses the terminal holding portion 23d forward. This bobbin pressing portion presses the terminal holding portion 23d to press the flange portion 23c against the annular plate portion 19a. In this case, it is preferable that the bobbin pressing portion presses a portion of the terminal holding portion 23d that is away from the terminal pin 12. For example, it is preferable that the bobbin pressing portion presses both ends of the terminal holding portion 23d in the left-right direction.

According to the inventor's study, compared to the case where the board holder 14 has a bobbin pressing portion that presses the terminal holding portions 22d and 23d, the board holder 14 having the bobbin pressing portions 14c and 14d as in the above-described embodiment makes it easier to suppress rattling of the bobbins 22 and 23 against the stator cores 18 to 21 when the rotor 4 is rotating. In addition to the bobbin pressing portion 14c, in the above-described embodiment, the board holder 14 may have a bobbin pressing portion that contacts the terminal holding portion 22d from the front side and presses the terminal holding portion 22d rearward, or may have a bobbin pressing portion that contacts the terminal holding portion 23d from the rear side and presses the terminal holding portion 23d frontward in addition to the bobbin pressing portion 14d.

In the above embodiment, the bobbin pressing portion 14c may press the flange portion 22b rearward, and the bobbin pressing portion 14d may press the flange portion 23b forward, thereby pressing the terminal holding portion 22d and the terminal holding portion 23d together. That is, the board holder 14 may be provided with bobbin pressing portions 14c and 14d that press the bobbins 22 and 23 together in the front-rear direction, in a direction in which the two bobbins 22 and 23 approach each other. In this case, the rear surface of the terminal holding portion 22d and the front surface of the terminal holding portion 23d come into contact with each other, and gaps are formed between the annular plate portion 18a and the flange portion 22c, and between the annular plate portion 19a and the flange portion 23c in the front-rear direction.

Even in this case, it is possible to prevent the board holder 14 from moving relative to the stator cores 18 to 21 in the front-rear direction, and the bobbins 22 and 23 can be prevented from moving relative to the board holder 14 in the front-rear direction. It becomes possible to prevent this from happening. Therefore, it is possible to prevent the bobbins 22 and 23 from moving relative to the stator cores 18 to 21, and as a result, the bobbins 22 and 23 are prevented from shaking relative to the stator cores 18 to 21 when the rotor 4 is rotating. becomes possible to suppress.

In the above-described embodiment, if the contact portion 14e can be brought into contact with a portion of the stator core 20 from the rear side, the contact portion 14e may be in contact with a portion of the stator core 20 from the rear side with a predetermined contact pressure. Also, in the above-described embodiment, if the contact portion 14f can be brought into contact with a portion of the stator core 21 from the front side, the contact portion 14f may be in contact with a portion of the stator core 21 from the front side with a predetermined contact pressure.

In the above-mentioned embodiment, the stator 7 may not include, for example, the driving coil 6, the bobbin 23, and the stator cores 19 and 21. In this case, for example, the end plate 9 is fixed to the rear surface of the annular plate portion 18a of the stator core 18. In this case, for example, as in the above-mentioned embodiment, the substrate holder 14 includes a bobbin pressing portion 14c that presses the flange portion 22b rearward to press the flange portion 22c against the annular plate portion 18a, or the substrate holder 14 includes a bobbin pressing portion that presses the flange portion 22c forward to press the flange portion 22b against the annular plate portion 20a. Even in this case, it is possible to suppress rattling of the bobbin 22 against the stator cores 18 and 20 when the rotor 4 is rotating.

Further, when the stator 7 does not include the drive coil 6, the bobbin 23, and the stator cores 19, 21, the board holder 14 contacts the flange 22b from the front side and presses the flange 22b backward. and a bobbin pressing part that contacts the flange 22c from the rear side and presses the flange 22c forward. That is, the substrate holder 14 may include two bobbin pressing parts that contact the bobbin 22 with a predetermined contact pressure from both sides in the front-rear direction and press the bobbin 22.

Even in this case, it is possible to prevent the substrate holder 14 from moving relative to the stator cores 18, 20 in the front-rear direction, and it is also possible to prevent the bobbin 22 from moving relative to the substrate holder 14 in the front-rear direction. Therefore, it is possible to prevent the bobbin 22 from moving relative to the stator cores 18, 20, and as a result, it is possible to suppress rattling of the bobbin 22 relative to the stator cores 18, 20 when the rotor 4 is rotating.

In the above-mentioned embodiment, the number of bobbin pressing portions 14c of the substrate holder 14 may be two or more, and the number of bobbin pressing portions 14d of the substrate holder 14 may be two or more. In the above-mentioned embodiment, the number of contact portions 14e of the substrate holder 14 may be one or three or more, and the number of contact portions 14f of the substrate holder 14 may be one or three or more. In the above-mentioned embodiment, one protrusion formed on the substrate holder 14 may have the function of the bobbin pressing portion 14c and the function of the contact portion 14e, and one protrusion formed on the substrate holder 14 may have the function of the bobbin pressing portion 14d and the function of the contact portion 14f.

In the above-mentioned embodiment, if the mounting state of the board holder 14 to the stator cores 18 to 21 can be stabilized, the board holder 14 does not need to have the contact portions 14h to 14k. Also, in the above-mentioned embodiment, the case portion 20b of the stator core 20 may cover the outer peripheral surface of the drive coil 6 in addition to the drive coil 5. In this case, the case portion 21b of the stator core 21 becomes unnecessary. Also, in the above-mentioned embodiment, the case portion 21b may cover the outer peripheral surface of the drive coil 5 in addition to the drive coil 6. In this case, the case portion 20b becomes unnecessary. Furthermore, in the above-mentioned embodiment, the feed screw does not need to be formed on the rotating shaft 2.

1 Motor (stepping motor)
2 Rotating shaft 3 Driving magnet 4 Rotor 5, 6 Driving coil 7 Stator 8 Frame (fixing member, first fixing member)
9 End plate (fixing member, second fixing member)
12 terminal pin 13 board 14 board holder 14c bobbin pressing part (first bobbin pressing part)
14d Bobbin pressing part (second bobbin pressing part)
14e Contact part (first contact part)
14f Contact part (second contact part)
14h, 14i, 14j, 14k contact part (third contact part)
17 Pole teeth 18, 19 Stator core (inner stator core)
18a, 19a, 20a, 21a Annular plate portion 20, 21 Stator core (outer stator core)
20b, 21b Case part 22, 23 Bobbin 22a, 23a Cylindrical part 22b, 23b Flange part (the other collar part)
22c, 23c Tsuba (one tsuba)
22d, 23d Terminal holding part 26 Opening X Axial direction of rotating shaft Y Orthogonal direction

Claims (10)

A rotor having a rotating shaft and a driving magnet, a stator having a driving coil and disposed on the outer peripheral side of the driving magnet, a terminal pin to which an end of the driving coil is electrically connected, and the terminal. comprising a substrate to which a pin is fixed, and a substrate holder that holds the substrate,
The stator includes a stator core having a plurality of pole teeth arranged to face the outer peripheral surface of the driving magnet, a cylindrical cylindrical part arranged on the outer periphery side of the plurality of pole teeth, and both ends of the cylindrical part, respectively. A bobbin having a flange that spreads out in the shape of a flange, and the driving coil wound around the outer peripheral surface of the cylindrical part,
The substrate holder includes a bobbin pressing portion that pushes the bobbin toward one side in the axial direction of the rotating shaft and presses one of the two flanges against the stator core; A stepping motor comprising: contact portions that contact the stator core or a fixing member fixed to the stator core on both sides with a predetermined contact pressure in the axial direction of the rotating shaft. the stator core includes a flat, annular plate portion to which the roots of the plurality of pole teeth are connected,
the stator includes two of the bobbins and two of the drive coils arranged in the axial direction of the rotating shaft, and includes, as the stator core, two inner stator cores, the annular plate portion of which is disposed between the two drive coils in the axial direction of the rotating shaft, and two outer stator cores, the annular plate portion of which is disposed outside the two drive coils in the axial direction of the rotating shaft;
2. The stepping motor according to claim 1, wherein the substrate holder includes, as the bobbin pressing portion, a first bobbin pressing portion that presses the flange portion of one of the two bobbins against the annular plate portion of one of the two inner stator cores, and a second bobbin pressing portion that presses the flange portion of the other of the two bobbins against the annular plate portion of the other of the two inner stator cores. The bobbin includes a terminal holding part that holds the terminal pin,
The outer stator core includes a cylindrical case portion that covers the outer peripheral surface of the drive coil,
One end of the case portion is connected to the annular plate portion,
The other ends of the case portions of the two outer stator cores are fixed to each other with the other ends of the case portions of the two outer stator cores in contact with each other,
The two case parts fixed to each other have an opening for arranging the terminal holding part,
3. The stepping motor according to claim 2, wherein the substrate holder partially closes the opening. The fixing member includes a first fixing member fixed to one end surface of the stator in the axial direction of the rotating shaft, and a second fixing member fixed to the other end surface of the stator in the axial direction of the rotating shaft. Equipped with
4. The substrate holder includes, as the contact portions, a first contact portion that contacts the first fixing member and a second contact portion that contacts the second fixing member. stepper motor. 5. The bobbin pressing section according to claim 4, wherein the bobbin pressing section contacts the other one of the two flange sections and presses the other one of the two flange sections. stepping motor. The substrate holder includes one first bobbin pressing section, one second bobbin pressing section, and is arranged on both sides of the first bobbin pressing section in an orthogonal direction perpendicular to an axial direction of the rotating shaft. The stepping motor according to claim 5, characterized in that the stepping motor comprises two of the first contact parts and two of the second contact parts arranged on both sides of the second bobbin pressing part in the orthogonal direction. . The stepping motor according to claim 3, characterized in that the bobbin pressing portion contacts the terminal holding portion and presses the terminal holding portion. The stepping motor according to any one of claims 1 to 7, characterized in that the substrate holder is provided with a third contact portion that contacts the stator core with a predetermined contact pressure in an orthogonal direction perpendicular to the axial direction of the rotation shaft on both sides of the orthogonal direction. a rotor having a rotating shaft and a drive magnet, a stator having a drive coil and disposed on the outer periphery of the drive magnet, terminal pins to which ends of the drive coil are electrically connected, a substrate to which the terminal pins are fixed, and a substrate holder for holding the substrate;
The stator includes a stator core having a plurality of pole teeth arranged to face an outer circumferential surface of the drive magnet, two bobbins each having a cylindrical portion arranged on the outer circumferential side of the plurality of pole teeth and flange portions extending in a flange-like shape from both ends of the cylindrical portion, and the two drive coils wound around the outer circumferential surface of the cylindrical portion,
the two bobbins and the two drive coils are arranged in the axial direction of the rotating shaft,
a bobbin pressing portion that presses the two bobbins together in a direction in which the two bobbins approach each other in the axial direction of the rotating shaft, and a contact portion that contacts the stator core or a fixed member fixed to the stator core with a predetermined contact pressure in the axial direction of the rotating shaft on both sides in the axial direction of the rotating shaft. a rotor having a rotating shaft and a drive magnet, a stator having a drive coil and disposed on the outer periphery of the drive magnet, terminal pins to which ends of the drive coil are electrically connected, a substrate to which the terminal pins are fixed, and a substrate holder for holding the substrate;
the stator comprises a stator core having a plurality of pole teeth arranged to face an outer circumferential surface of the drive magnet, a bobbin having a cylindrical portion arranged on the outer circumferential side of the plurality of pole teeth and flange portions extending in a flange-like shape from both ends of the cylindrical portion, and the drive coil wound around the outer circumferential surface of the cylindrical portion,
a bobbin pressing portion that contacts the bobbin with a predetermined contact pressure from both sides in the axial direction of the rotating shaft to press the bobbin, and a contact portion that contacts the stator core or a fixed member fixed to the stator core with a predetermined contact pressure in the axial direction of the rotating shaft on both sides in the axial direction of the rotating shaft.

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