Actuator

Abstract

The present invention provides a lighter actuator. The actuator comprises: a motor and a housing having a housing for the motor, wherein the motor comprises: a frame having a plurality of corners and a face portion between two adjacent corners; one or more magnets arranged on the inner side of the frame, wherein the magnets and the frame are bonded to each other by an adhesive in the direction of the rotation axis, wherein magnetic pole units of the one or more magnets are arranged at the plurality of corners, wherein a reinforcing member extending in the circumferential direction is arranged along the face portion of the frame, wherein the reinforcing member extends in the radial direction between the frame and the housing, wherein the reinforcing member is formed by a member different from a member forming the frame, wherein the housing has a plurality of corners and a face portion between two adjacent corners, wherein a rib is arranged on the face portion of the housing, wherein the rib extends in the circumferential direction relative to the motor arranged in the housing.

Description

[0001] This application is a divisional application of the patent application with application number 201810173475.9, application date March 2, 2018, and invention name Motor and Actuator. Technical Field

[0002] The present invention relates to an actuator, and in particular, to an actuator in which a magnet is mounted on the inner side of a frame. Background Art

[0003] Some motors used for actuators and the like have a structure in which a magnet is mounted inside a frame.

[0004] Patent Document 1 below discloses a DC motor structure including a permanent magnet in surface contact with the inner surface of a motor case. In this DC motor, a buffer (shock absorber) having elasticity is sandwiched in a laminated manner between the motor case and the permanent magnet in surface contact.

[0005] Prior art document: Patent document 1: Japanese Utility Model Publication No. H04-28759

[0006] However, there is a demand for further weight reduction in the above-mentioned motors. Summary of the invention

[0007] The present invention is made to solve the above-mentioned problems, and an object of the present invention is to provide a lighter motor and actuator.

[0008] In order to achieve the above-mentioned purpose, according to the technical solution of one aspect of the invention, a motor includes: a frame; and one or more magnets arranged on the inner side of the frame, a gap extending in the circumferential direction is provided between the inner circumferential surface of the frame and the outer circumferential surface of the magnet, and in the direction of the rotation axis, the magnets located on both sides of the gap are connected to the frame by an adhesive.

[0009] Preferably, the frame has a plurality of corners and a face portion located between two adjacent corners, and one or more magnetic pole units of magnets are arranged at the plurality of corners.

[0010] Preferably, the magnet is annular and has a plurality of magnetic pole units.

[0011] Preferably, the plurality of magnets are respectively arranged at the plurality of corners, and the plurality of magnets respectively have a magnetic pole unit.

[0012] Preferably, the frame has reinforcing members or ribs extending in the radial direction and in the circumferential direction.

[0013] Preferably, the frame has a plurality of corners and a face portion located between two adjacent corners, and a reinforcing member or a rib is provided on the face portion, and the reinforcing member or the rib extends in the radial direction and in the circumferential direction.

[0014] Preferably, the end portion of the reinforcing member or the rib is provided at one of the two adjacent corner portions.

[0015] Preferably, the reinforcement member is formed from a different member from the frame.

[0016] Preferably, the ribs are formed by recesses or projections of the frame.

[0017] Preferably, the motor includes a bracket having an outer peripheral surface that is a shape closed in an annular shape, and the inner peripheral surface of the frame contacts the outer peripheral surface of the bracket.

[0018] Preferably, the bracket has a cylindrical portion, the cylindrical portion has an opening through which the rotating shaft passes, and the cylindrical portion has an outer peripheral surface.

[0019] Preferably, in the rotation axis direction, the outer peripheral surface of the bracket extends toward the magnet.

[0020] Preferably, the frame has a plurality of corners and a face portion located between two adjacent corners, and an outer peripheral surface of the bracket facing the face portion of the frame has radial rigidity.

[0021] According to the technical solution of another aspect of the invention, an actuator comprises: the above-mentioned motor, and a box body having a housing portion for the motor, the housing portion having a plurality of corners and a face portion located between two adjacent corners, a reinforcing member or rib is provided on the face portion of the housing portion, and the reinforcing member or rib extends in the radial direction of the motor.

[0022] Preferably, the frame has a plurality of corners and a face portion located between two adjacent corners, and the reinforcing member or the rib urges the face portion of the frame toward the inside of the motor.

[0023] Preferably, an end portion of the reinforcing member or the rib is provided at one of the two adjacent corner portions of the accommodating portion.

[0024] Preferably, the reinforcing member is formed as a member different from the box body.

[0025] Preferably, the rib is formed with a protrusion, or is formed between a plurality of recesses of the case.

[0026] According to these inventions, a lighter actuator can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a cross-sectional view showing a motor in one embodiment of the present invention.

[0028] Figure 2 is along Figure 1 Cross-sectional view of line A-A.

[0029] Figure 3 It is an exploded perspective view of the frame assembly.

[0030] Figure 4 It is a diagram for explaining the area where the adhesive is arranged with respect to the magnet.

[0031] Figure 5 is along Figure 1 Cross-sectional view of the C-C line.

[0032] Figure 6 is a perspective view showing the bracket and the plate.

[0033] Figure 7 This is a diagram for explaining the vibration mode of the motor.

[0034] Figure 8 This is a diagram for explaining the analysis results of the vibration mode of the motor.

[0035] Fig. 9 This is a perspective view showing a magnet of a motor according to a modified example of the present embodiment.

[0036] Fig.10 It is a diagram for explaining the area where the adhesive is arranged with respect to the magnet.

[0037] Fig.11 It is a cross-sectional view of the motor involved in this modification.

[0038] Fig.12 It is a diagram for explaining an example of arrangement of adhesive with respect to a magnet.

[0039] Fig.13 This is a perspective view showing a magnet of a motor according to another modified example of the present embodiment.

[0040] Fig.14 This is a perspective view showing a frame according to another modified example of the present embodiment.

[0041] Fig.15 This is a perspective view showing a frame according to another modified example of the present embodiment.

[0042] Fig.16 It is a perspective view for explaining the structure of an actuator according to another modified example of the present embodiment.

[0043] Fig.17 It is a cross-sectional view of the receiving portion perpendicular to the rotation axis.

[0044] Description of reference numerals:

[0045] 1: motor; 2: rotating shaft; 10, 210, 310: frame; 11: plane portion of the frame (an example of the face); 12: corner portion of the frame; 30: bracket (an example of the cylinder); 30a: outer peripheral surface of the bracket; 35: opening; 40: plate; 50, 150: magnet; 50a, 150a: outer peripheral surface of the magnet; 61 (61a, 61b, 61c, 61d): magnetic pole unit (to be Element); 70: adhesive; 80: gap; 215, 315: rib of the frame; 215a, 215b, 315a, 315b: end of the rib of the frame; 501: actuator; 503: box; 510: accommodating portion; 511: flat portion of the accommodating portion (an example of the face); 512: corner of the accommodating portion; 515: rib of the accommodating portion; 515a, 515b: end of the rib of the accommodating portion DETAILED DESCRIPTION

[0046] Hereinafter, an example of a motor and an actuator using the motor in the embodiment of the present invention will be described.

[0047] In the following description, the direction parallel to the axis of the motor is sometimes referred to as the rotation axis direction. In addition, the rotation axis direction is sometimes referred to as the up-down direction (the direction in which the axis protrudes when viewed from the frame of the motor is upward). The "up-down", "up", "down", etc. mentioned here are only used for the sake of convenience when focusing on the motor, and do not limit the direction in the device on which the motor is mounted or the usage posture of the motor.

[0048] [Implementation Method]

[0049] Figure 1 This is a cross-sectional view showing a motor 1 in one embodiment of the present invention.

[0050] Figure 1 The cross-sectional view shown is described later. Figure 2 The cross section is shown along the BB line in FIG. In the following figures, arrow A1 indicates the direction of the rotation axis. The direction where the arrow tip of arrow A1 is located is upward.

[0051] The motor 1 is, for example, a DC motor and generally includes a frame assembly 1 a and an armature assembly 1 b rotatable relative to the frame assembly 1 a.

[0052] The armature assembly 1b has a rotating shaft (shaft) 2, an armature part 4, a commutator part 6, etc. The armature part 4 is mounted on the rotating shaft 2. The armature part 4 has an armature core 5 having a plurality of salient poles protruding in the radial direction and a winding (not shown) wound around each salient pole. The commutator part 6 is provided near one end of the rotating shaft 2. As described later, the commutator part 6 has a brush 25 provided on the frame assembly 1a, a commutator 7 contacting the brush 25, etc.

[0053] The frame assembly 1 a is composed of a frame (motor case) 10 , a bracket 30 , a plate 40 , a magnet 50 , and the like.

[0054] The frame 10 includes an upper end and a lower end, and the upper end has a cylindrical shape covered with a surface. That is, the frame 10 has a cup shape with the lower end being an opening. Figure 1 The opening of the frame 10 (the right end in the middle) is blocked by a plate 40. The armature assembly 1b is accommodated in the housing composed of the frame 10 and the plate 40.

[0055] The bracket 30 is attached to the inner side of the plate 40. The bracket 30 holds the terminal 26 to which the current is supplied from the outside. The terminal 26 is connected to the brush 25. The brush 25 is held so as to be in contact with the commutator 7.

[0056] The rotating shaft 2 passes through the upper surface of the frame 10. That is, the upper end of the rotating shaft 2 protrudes from the frame 10 to the outside of the frame 10, and the other parts of the rotating shaft 2 are accommodated. A bearing 21 is held in the center of the upper surface of the frame 10. In addition, a bearing 22 is held in the center of the plate 40. The rotating shaft 2 is supported by the bearings 21 and 22 at two locations so as to be rotatable relative to the frame 10.

[0057] Figure 2 is along Figure 1 Cross-sectional view of line A-A.

[0058] like Figure 2 As shown, in this embodiment, a set of four magnets 50 is provided. Each magnet 50 is arranged inside the frame 10. The frame assembly 1a has a cross-sectional structure in which the outer peripheral surface 50a of each magnet 50 is surrounded by the frame 10. The outer peripheral surface of the frame 10 becomes the outer peripheral surface of the motor 1.

[0059] The frame 10 is formed using a magnetic material. The frame 10 has a plurality of corners 12 and a plane portion (as an example of a face portion) 11 located between two adjacent corners 12. Specifically, the frame 10 has an outer shape having four plane portions 11 and four corner portions 12, respectively. Two plane portions 11 adjacent in the circumferential direction are connected (continuous) to each other via one corner portion 12. One of the two plane portions 11 adjacent in the circumferential direction is approximately perpendicular to the other. The corner portion 12 has a rounded shape (R shape). The frame 10 is approximately square in a cross section perpendicular to the rotation axis 2. The frame 10 as a whole is formed in a shape having a plurality of corners.

[0060] The frame 10 has a substantially uniform thickness. That is, the inner peripheral surface 10 b of the frame 10 is formed in a square shape by connecting a plurality of flat portions formed by the planar portions 11 and portions having rounded corners formed by the corner portions 12 .

[0061] The magnet 50 is, for example, a bonded magnet formed using a known rare earth material and a known resin material. The magnet 50 is not limited to a bonded magnet, and may be, for example, a sintered magnet.

[0062] The four magnets 50 each have a magnetic pole unit 61 (N pole 61a, S pole 61b, N pole 61c, S pole 61d). That is, the four magnets have the same number of magnetic pole units 61 as the number of corners 12 of the motor 1. The magnetic pole units 61 are arranged in a manner that the polarities are different from each other in the circumferential direction. The four magnets 50 are arranged at the four corners 12 of the frame 10 in a state where the magnetic pole units 61 are opposite to each other (face to face). That is, for one set of magnets 50, the conversion parts of the four magnetic pole units 61 are respectively located at positions that overlap with the planar portion 11 of the frame 10 in the radial direction.

[0063] Each of the four magnets 50 has an outer peripheral surface 50a with a rounded shape along the inner peripheral surface 10b of the frame 10 along the corner 12. Each of the four magnets 50 has a cylindrical inner peripheral surface 50b. A small gap is provided between the inner peripheral surface 50b of each magnet 50 and the armature core 5. Each of the four magnets 50 is arranged in a manner that a gap is separated between adjacent magnets 50 in the circumferential direction. That is, in the frame assembly 1a, a portion of the inner peripheral surface 10b of each flat portion 11 is exposed toward the armature assembly 1b. In addition, the inner peripheral surface 10b of the other portion of each flat portion 11 is covered by the magnet 50 by being arranged thereon. In this way, except for the portion where the inner peripheral surface 10b of the frame 10 is exposed, the armature core 5 is covered over substantially the entire circumference by the cylindrical surface formed by the inner peripheral surfaces 50b of the four magnets 50.

[0064] In the present embodiment, the magnet 50 is bonded to the inner peripheral surface 10 b of the frame 10 by the adhesive 70 . That is, the adhesive 70 is present between the outer peripheral surface 50 a of the magnet 50 and the inner peripheral surface 10 b of the frame 10 .

[0065] Figure 3 It is an exploded perspective view of the frame assembly 1a.

[0066] exist Figure 3 The bracket 30 is omitted in the figure.

[0067] like Figure 3 As shown, four magnets 50 are placed into the inner side of the frame 10 from the opening at the lower side of the frame 10 and bonded to the inner peripheral surface 10b of the frame 10. Then, the armature assembly 1b is placed inside the frame 10, and the bracket 30 and the plate 40 are mounted on the frame 10 to assemble the motor 1.

[0068] Figure 4 It is a diagram for explaining a region where the adhesive 70 is arranged on the magnet 50 .

[0069] The adhesive 70 is formed of a known resin material and is applied to the outer peripheral surface 50a of each magnet 50 by coating or the like. The adhesive 70 is not applied to the entire outer peripheral surface 50a of each magnet 50, but is applied to a partial area. Specifically, the adhesive 70 is applied to the following areas of the outer peripheral surface 50a, for example.

[0070] like Figure 4 As shown, it is assumed that the outer peripheral surface 50a is divided into three areas (upper outer peripheral surface 55T, middle outer peripheral surface 55C and lower outer peripheral surface 55B) along the rotation axis direction. The upper outer peripheral surface 55T is the area of ​​the upper third of the outer peripheral surface 50a. The lower outer peripheral surface 55B is the area of ​​the lower third of the outer peripheral surface 50a. The middle outer peripheral surface 55C is the remaining one-third of the area between the upper outer peripheral surface 55T and the lower outer peripheral surface 55B. In this embodiment, the adhesive 70 is arranged in the two areas of the upper outer peripheral surface 55T and the lower outer peripheral surface 55B. The adhesive 70 is not arranged in the middle outer peripheral surface 55C. That is, the adhesive 70 is arranged in the upper area and the lower area in the rotation axis direction, but not in the central area in the rotation axis direction. The adhesive 70 is arranged in two areas that are not adjacent to each other among the three areas divided in the rotation axis direction constituting the outer peripheral surface 50a.

[0071] like Figure 1 As shown in the figure, by disposing the adhesive 70 in a partial area of ​​the outer peripheral surface 50a of the magnet 50, a gap 80 is provided between the inner peripheral surface 10b of the frame 10 and the outer peripheral surface 50a of the magnet 50. Therefore, in the rotation axis direction, the adhesive 70 for bonding the magnet 50 to the frame 10 is provided on both sides of the gap 80. In other words, the magnet 50 and the frame 10 located on both sides of the gap 80 are connected by the adhesive 70.

[0072] Specifically, the gap 80 is provided between the middle outer peripheral surface 55C and the inner peripheral surface 10b of the frame 10. The gap 80 extends in the circumferential direction. The adhesive 70 is provided on the upper side of the gap 80. That is, the adhesive 70 is sandwiched between the upper outer peripheral surface 55T and the inner peripheral surface 10b of the frame 10. In addition, the adhesive 70 is provided on the lower side of the gap 80. That is, the adhesive 70 is sandwiched between the lower outer peripheral surface 55B and the inner peripheral surface 10b of the frame 10.

[0073] Moreover, depending on the bonding conditions between the magnet 50 and the frame 10, the interval between the inner circumferential surface 10b of the frame 10 and the outer circumferential surface 50a of the magnet 50 may be slightly different at different positions. For this reason, the adhesive 70 applied to the upper outer circumferential surface 55T and / or the lower outer circumferential surface 55B may overflow upward or downward, or the area of ​​the gap 80 may be expanded slightly. In addition, the ratio of each area 55T, 55C, and 55B is not limited to one-third each, and any area may be widened or narrowed. In addition, the ratio of each area 55T, 55C, and 55B may be one-quarter, two-quarters, and one-quarter, respectively.

[0074] Figure 5 is along Figure 1 Cross-sectional view of the C-C line.

[0075] along Figure 1 The cross section of the CC line is the cross section of the area where the middle outer peripheral surface 55C is located. Figure 5 As shown, in this region, the adhesive 70 is not disposed between the outer peripheral surface 50a of the magnet 50 and the inner peripheral surface 10b of the frame 10. That is, between the outer peripheral surface 50a of the magnet 50 and the inner peripheral surface 10b of the frame 10, a gap 80 extending in the circumferential direction is provided.

[0076] Figure 6 3 is a perspective view showing the bracket 30 and the plate 40 .

[0077] exist Figure 6 The upper side of the bracket 30 and the plate 40 is shown in FIG. Figure 6 As shown, two terminals 26 are mounted on the bracket 30. One end of each brush 25 is connected to the terminal 26. Thus, the two brushes 25 are each supported by the terminal 26. The other end of each brush 25 is in contact with the commutator 7 of the armature assembly 1b.

[0078] The bracket 30 is formed of, for example, a resin member. The bracket 30 has a thickness in the direction of the rotation axis. The bracket 30 has a cylindrical portion having an opening 35 through which the rotation axis 2 passes. In the present embodiment, the bracket 30 is a cylindrical portion having an opening 35 in the center. The brush 25 is arranged in the opening 35. In addition, the rotation axis 2 passes through the opening 35. The bracket 30 has an outer peripheral surface 30a in a closed annular shape. That is, the cylindrical portion has an outer peripheral surface 30a.

[0079] When viewed from the rotation axis direction (planar view), the outer peripheral surface 30a of the cylinder has substantially the same shape as the inner peripheral surface 10b of the frame 10. That is, the bracket 30 has four corners 32 and a flat surface 31 provided between two adjacent corners 32. The outer peripheral surface 30a of the cylinder is provided at the four corners 32 and the four flat surfaces 31. Figure 1As shown, in the rotation axis direction, the outer peripheral surface 30a of the bracket 30 extends toward the magnet 50. The length of the bracket 30 in the rotation axis direction is, for example, slightly larger than the dimension of the brush 25 in the rotation axis direction.

[0080] The bracket 30 is provided with a recess 37 that is formed concave from the upper side to the lower side. Between the outer peripheral surface 30a of the cylinder and the inner peripheral surface 30b that constitutes the opening 35, there is a resin member in addition to the recess 37 and other hole portions. By providing the recess 37, the bracket 30 can be easily formed. The bracket 30 has rigidity in the radial direction. That is, in the bracket 30, the wall thickness in the radial direction is ensured to a certain extent from the outer peripheral surface 30a toward the inside, and even if a radial force is applied to a portion of the outer peripheral surface 30a, the bracket 30 is difficult to be distorted. The recess 37 is provided in consideration of the rigidity of the bracket 30 in a manner that the radial rigidity of the bracket 30 is not significantly impaired.

[0081] When the bracket 30 is attached to the frame 10, the outer peripheral surface 30a of the bracket 30 contacts the inner peripheral surface 10b of the frame 10. The flat surface 31 of the outer peripheral surface 30a of the bracket 30 facing the flat surface 11 of the frame 10 has radial rigidity.

[0082] As described above, in this embodiment, between the outer peripheral surface 50a of the magnet 50 and the inner peripheral surface 10b of the frame 10, there is provided a gap 80 extending in the circumferential direction, and adhesive 70 is arranged on both sides thereof. That is, the adhesive 70 is not applied to the middle peripheral surface 55C which occupies one-third of the area of ​​the peripheral surface 50a, and the adhesive 70 is applied to the upper peripheral surface 55T and the lower peripheral surface 55B which occupy the remaining two-thirds of the area. Since the area where the adhesive 70 is not arranged is provided in this way, the amount of adhesive 70 used can be reduced. Therefore, the motor 1 can be made lightweight. In addition, the manufacturing cost of the motor 1 can be reduced.

[0083] Here, the area where the adhesive 70 is applied is limited to the upper outer peripheral surface 55T and the lower outer peripheral surface 55B. Thus, the radial natural frequency of the motor 1 can be maintained at the same natural frequency as when the adhesive 70 is applied to the entire area of ​​the outer peripheral surface 50a.

[0084] That is, in an inner rotor type motor such as the motor 1, the radial natural vibration of the combination formed by combining the magnet 50 and the frame 10 occurs during the operation of the motor 1, thereby generating noise. In most cases, for the combination of the magnet 50 and the frame 10, the annular second-order mode (annular second-order mode) described later is the most representative natural vibration mode. In the motor 1, among the radial electromagnetic forces, if the frequency of the high harmonics is consistent with the radial natural frequency of the combination of the magnet 50 and the frame 10, the amplitude of the vibration under the annular second-order mode becomes high, and significant vibration and noise occur, which becomes a problem. In recent years, in particular, there are many cases where neodymium magnets with relatively high magnetic force are used as magnets 50. Therefore, the amplitude of the high harmonics of the radial electromagnetic force becomes high, and there is a situation where such a resonance problem is surfaced.

[0085] Figure 7 This is a diagram for explaining the vibration mode of the motor 1 . Figure 8 This is a diagram for explaining the analysis results of the vibration mode of the motor 1 .

[0086] exist Figure 7 , a cross section of the frame 10 perpendicular to the rotation axis 2 is schematically shown. In the vibration of the annular second-order mode, the frame 10 alternately repeats the deformation state shown by the two-dot chain line and the deformation state shown by the dotted line (the deformation amount is exaggerated). That is, there are nodes N near the four corners 12, and the antinode AN is near the center of the four plane parts 11. The annular second-order mode can refer to a mode in which the parts facing each other in the radial direction vibrate in opposite phases, and the adjacent parts vibrate in opposite directions in the radial direction.

[0087] exist Figure 8 , the deformation state of the motor 1 during vibration in the toroidal second-order mode is schematically shown by eigenvalue analysis. In the figure, the portion with the larger maximum value of the displacement of the frame 10 of the motor 1 is colored with a lower concentration.

[0088] When the magnet is bonded to the frame, there is a case where the adhesive is applied to the entire outer circumference of the magnet. In this case, the entire outer circumference of the magnet is bonded to the inner circumference of the frame to form a structure in which the magnet and the frame are integrated. As a result, the natural frequency of the second-order mode of the ring can be transferred to a higher value, thereby suppressing the occurrence of electromagnetic vibration noise. On the other hand, if the adhesive is applied to the entire outer circumference of the magnet, there is a case where the amount of adhesive used increases, and the manufacturing cost of the motor increases. In addition, if there is a lot of adhesive, there is a case where the motor becomes heavier.

[0089] In this case, in the present embodiment, since the adhesive 70 is disposed in the limited area of ​​both the upper outer peripheral surface 55T and the lower outer peripheral surface 55B, the amount of adhesive 70 used can be reduced as described above. Therefore, the manufacturing cost of the motor 1 can be reduced. In addition, the motor 1 can be made lighter. Moreover, only one of the reduction in manufacturing cost and the lightening of the motor 1 can be achieved.

[0090] The adhesive 70 is disposed on the upper outer peripheral surface 55T and the lower outer peripheral surface 55B of the outer peripheral surface 50a of the magnet 50, which are separated from each other in the direction of the rotation axis. Therefore, the frame 10 can be fixed to the magnet 50 at two locations separated from each other in the direction of the rotation axis, so the frame 10 and the magnet 50 can be assembled as a whole. Moreover, according to the results of the eigenvalue analysis performed by simulation, in this embodiment, it was confirmed that the natural frequency in the radial direction can be maintained at a level substantially the same as that in the case where the adhesive 70 is applied to the entire outer peripheral surface 50a of the magnet 50. That is, the noise generated by vibration can be suppressed in the same manner as when the adhesive 70 is applied to the entire outer peripheral surface 50a of the magnet 50. By limiting the natural frequency to an area outside the audible range (above 10kHz), the motor 1 can be made lightweight while maintaining the suppression of abnormal noise.

[0091] Specifically, for example, the radial natural frequency when the adhesive 70 is arranged on the entire outer peripheral surface 50a is 11734Hz. In contrast, the radial natural frequency when the adhesive 70 is arranged on one-third of the area at both ends of the outer peripheral surface 50a in the direction of the rotation axis as in the present embodiment is 11665Hz. The radial natural frequency is only reduced by 0.6% compared with the case where the adhesive 70 is arranged on the entire outer peripheral surface 50a. That is, it can be considered that even if the adhesive 70 is reduced, there is actually little effect on vibration and noise. Compared with the case where the adhesive 70 is arranged on the entire outer peripheral surface 50a, the amount of adhesive 70 used can be reduced by about one-third. Therefore, the manufacturing cost of the motor 1 can be reduced. In addition, the motor 1 can be made lightweight.

[0092] Furthermore, in the present embodiment, the outer peripheral surface 30a of the bracket 30 is in contact with the inner peripheral surface 10b of the frame 10. Therefore, the area of ​​the inner peripheral surface 10b of the frame 10 that is not bonded to the magnet 50 in the direction of the rotation axis can be supported by the bracket 30, and the vibration of the motor 1 can be suppressed. Since the outer peripheral surface 30a of the bracket 30 has radial rigidity, the inner peripheral surface 10b of the frame 10 is reliably supported. Since the outer peripheral surface 30a of the bracket 30 extends toward the magnet 50 in the direction of the rotation axis, the inner peripheral surface 10b of the frame 10 can be reliably supported, and the vibration of the motor 1 can be suppressed. Furthermore, since the portion of the plane portion 11 of the frame 10 that is not supported by the magnet 50 can be supported by the outer peripheral surface 30a of the bracket 30, the vibration of the motor 1 can be suppressed and the occurrence of abnormal noise can be prevented.

[0093] The motor 1 uses a set of four magnets 50 separated at the switching portion of the magnetic pole unit 61 which does not greatly affect the operation of the motor 1. Therefore, the amount of magnets 50 used can be reduced while maintaining the performance of the motor 1. Therefore, the manufacturing cost of the motor 1 can be reduced, and the motor 1 can be made lighter.

[0094] [Description of Modifications]

[0095] In the following description, the same reference numerals as those described above are given to members or portions having the same configuration as those described above.

[0096] The magnet may also be ring-shaped.

[0097] Fig. 9 This is a perspective view showing a magnet 150 of a motor according to a modified example of the present embodiment.

[0098] exist Fig. 9 2 shows a magnet 150 of a motor according to a modified example of the present embodiment.

[0099] like Fig. 9 As shown, the magnet 150 is formed by a single member. The magnet 150 is annular. That is, the magnet 150 is formed in a cylindrical shape. The inner peripheral surface 150b of the magnet 150 is a cylindrical surface. The outer peripheral surface 150a of the magnet 150 has a shape along the inner peripheral surface 150b of the frame 10. That is, the magnet 150 has four corners 152 and four plane portions 151 located between each adjacent corner 152 corresponding to the frame 10.

[0100] Fig.10 It is a diagram for explaining a region where adhesive 70 is arranged on magnet 150 .

[0101] In this modification, as in the above-mentioned embodiment, the adhesive 70 is not arranged in the entire area of ​​the outer peripheral surface 150a of each magnet 150 but is arranged in a partial area. In this regard, specifically, as in the above-mentioned embodiment, the outer peripheral surface 150a is divided into one-third in the direction of the rotation axis, that is, divided into three areas of the upper outer peripheral surface 155T, the middle outer peripheral surface 155C, and the lower outer peripheral surface 155B. That is, the adhesive 70 is arranged in the two areas of the upper outer peripheral surface 155T and the lower outer peripheral surface 155B. The adhesive 70 is not arranged in the middle outer peripheral surface 155C. The adhesive 70 is arranged in the upper area and the lower area in the direction of the rotation axis, but not in the central area in the direction of the rotation axis. The adhesive 70 is arranged in two areas that are not adjacent to each other among the three areas that constitute the outer peripheral surface 150a in the direction of the rotation axis.

[0102] Fig.11 It is a cross-sectional view of the motor involved in this modification.

[0103] Fig.11 The cross section shown is similar to that of the motor 1 according to the above-mentioned embodiment. Figure 5 The cross section shown in FIG. 1 corresponds to the cross section shown in FIG. That is, a cross section through the middle outer peripheral surface 155C is shown. A magnetic pole unit 61 is provided at each of the four corners 152 of the magnet 150. That is, the magnet 150 has a plurality of magnetic pole units 61. The switching portions of the plurality of magnetic pole units 61 of the magnet 150 are each located on the plane portion 11 of the frame 10.

[0104] In this modification, by disposing the adhesive 70 in a partial area of ​​the outer peripheral surface 150a of the magnet 150, a gap 80 extending in the circumferential direction is provided between the inner peripheral surface 10b of the frame 10 and the outer peripheral surface 150a of the magnet 150. In the rotation axis direction, the adhesive 70 is present on both sides of the gap 80. That is, the adhesive 70 is present between the upper outer peripheral surface 155T and the inner peripheral surface 10b of the frame 10. In addition, the adhesive 70 is present between the lower outer peripheral surface 155B and the inner peripheral surface 10b of the frame 10.

[0105] Thus, in this variation, the area where the adhesive 70 is disposed is limited to the upper outer peripheral surface 155T and the lower outer peripheral surface 155B of the outer peripheral surface 150a of the magnet 150, and the adhesive 70 is not disposed on the middle outer peripheral surface 155C. In this case, as in the above-mentioned embodiment, the amount of adhesive 70 used can be reduced, and vibration can be suppressed. That is, the radial natural frequency of the combination of the frame 10 and the magnet 150 can be maintained at the same level as the case where the magnet 150 and the adhesive 70 are applied to the entire outer peripheral surface 150a of the magnet 150. Therefore, the occurrence of abnormal noise in the motor 1 can be suppressed, and the motor 1 can be lightweight. In addition, the occurrence of abnormal noise in the motor 1 can be suppressed, and the manufacturing cost of the motor 1 can be reduced at the same time.

[0106] Furthermore, the adhesive 70 may be disposed in a plurality of non-adjacent regions among the three or more regions that divide the outer peripheral surfaces 50a and 150a of the magnets 50 and 150 in the direction of the rotation axis. As an example, the case where the region not coated with the adhesive 70 is divided into two regions with respect to the magnet 150 will be described. Furthermore, the configuration of the adhesive 70 is not limited to this.

[0107] Fig.12 This is a diagram for explaining an example in which the adhesive 70 is arranged on the magnet 150 .

[0108] exist Fig.12 In the example shown, the outer peripheral surface 150a is divided into five regions in the rotation axis direction. That is, the outer peripheral surface 150a is composed of five regions from the upper side, namely, the upper outer peripheral surface 155T1, the first middle outer peripheral surface 155C1, the second middle outer peripheral surface 155C2, the third middle outer peripheral surface 155C3 and the lower outer peripheral surface 155B1.

[0109] At this time, the adhesive 70 is disposed, for example, on the upper outer peripheral surface 155T1, the second middle outer peripheral surface 155C2, and the lower outer peripheral surface 155B1. That is, the adhesive 70 is not disposed on the first middle outer peripheral surface 155C1 and the third middle outer peripheral surface 155C3. Thus, a gap 80 is provided between the first middle outer peripheral surface 155C1 and the inner peripheral surface 10b of the frame 10. In addition, a gap 80 is also provided between the third middle outer peripheral surface 155C3 and the inner peripheral surface 10b of the frame 10. In the rotation axis direction, the adhesive 70 is disposed on both sides of each gap 80.

[0110] Even with such an arrangement of the adhesive 70 , similarly to the above, the amount of adhesive 70 used can be reduced and the generation of abnormal noise in the motor 1 can be suppressed.

[0111] In addition, unlike Fig.12In the configuration example shown, the adhesive 70 may be disposed on the first middle outer peripheral surface 155C1 and the third middle outer peripheral surface 155C3, for example. Thus, a gap 80 is provided between the second middle outer peripheral surface 155C2 and the inner peripheral surface 10b of the frame 10. The adhesive 70 is disposed on both sides of the gap 80 in the rotation axis direction.

[0112] Even with such an arrangement of the adhesive 70, as described above, the amount of adhesive 70 used can be reduced and the occurrence of abnormal noise in the motor 1 can be suppressed. In particular, by arranging the adhesive 70 so that the adhesive 70 exists on both sides of the gap 80 in the direction of the rotation axis, the occurrence of abnormal noise in the motor 1 can be suppressed compared to the case where the same amount of adhesive 70 is applied to the entire area of ​​the outer peripheral surface 150a of the magnet 150.

[0113] Fig.13 This is a perspective view showing a magnet 50 of a motor according to another modified example of the present embodiment.

[0114] In this embodiment, ribs 59 may be provided on the outer peripheral surface 50a of the magnet 50. Ribs 59 are provided, for example, on the middle outer peripheral surface 55C where the adhesive 70 is not provided. Ribs 59 extend radially from the outer peripheral surface 50a. Ribs 59 are provided on each of the four magnets 50. Ribs 59 extend in the circumferential direction.

[0115] The rib 59 is, for example, a reinforcing member formed separately from the magnet 50. That is, the rib 59 is a member different from the magnet 50. The rib 59 is, for example, bonded to the magnet 50. Moreover, the method of mounting the rib 59 to the magnet 50 is not limited thereto. The rib 59 may be made of metal or resin. In addition, it may be made of other materials. Moreover, the rib 59 may be the same member as the magnet 50. That is, the rib 59 may be formed when the magnet 50 is formed.

[0116] By forming the rib 59 on the magnet 50 in this way, when the magnet 50 is bonded to the inner peripheral surface 10b of the frame 10, the rib 59 contacts the inner peripheral surface 10b. Thus, the portion where the gap 80 is provided between the frame 10 and the magnet 50 maintains the state where the frame 10 is applied with force by the rib 59. Therefore, the portion of the frame 10 to which the magnet 50 is not bonded is supported by the rib 59, and the natural frequency of the combination of the frame 10 and the magnet 50 becomes higher. Therefore, the vibration of the motor 1 can be suppressed, and the occurrence of abnormal noise in the motor 1 can be suppressed.

[0117] Furthermore, when the annular magnet 150 is used, the ribs may be provided in the same manner. The ribs may be provided on the middle outer peripheral surface 155C of the magnet 150 so as to contact the inner peripheral surface 10 b of the frame 10 .

[0118] Fig.14This is a perspective view showing a frame 210 according to another modified example of the present embodiment.

[0119] A frame having a reinforcing member or rib on the side may also be used. Alternatively, a frame having a reinforcing member or rib provided on the side may be used. The reinforcing member or rib extends in the radial direction. In addition, the reinforcing member or rib extends in the circumferential direction. The reinforcing member or rib is a reinforcing unit that increases the rigidity of the frame.

[0120] Specifically, for example, in Fig.14 In the frame 210 shown, three ribs 215 are formed on each of the four planar portions 11. The three ribs 215 are arranged at approximately equal intervals from each other in the direction of the rotation axis. Each rib 215 extends radially from the outer peripheral surface of the frame 210 to the outside of the frame 210. That is, each rib 215 protrudes outward from the outer peripheral surface of the frame 210. Each rib 215 extends in a direction approximately perpendicular to the planar portion 11 on which it is formed.

[0121] Each rib 215 extends in the circumferential direction. In this modified example, the ends 215a and 215b of each rib 215 are provided at the corner portion 12. That is, at one corner portion 12 adjacent to the plane portion 11 where each rib 215 is provided, there is one end 215a of the rib 215. In addition, at the other corner portion 12, there is the other end 215b of the rib 215.

[0122] Each rib 215 is a convex portion formed on the frame 210. That is, the portion where each rib 215 is provided is recessed in the inner peripheral surface 10b of the frame 210. The rib 215 can be provided by press working the metal plate constituting the frame 210 or the like.

[0123] As described above, since the ribs 215 are formed on the frame 210, the natural frequency of the frame 210 becomes higher than when the ribs 215 are not formed. Therefore, the vibration of the motor 1 can be suppressed, and the generation of abnormal noise in the motor 1 can be suppressed.

[0124] Since the rib 215 extends in the circumferential direction and the ends 215a and 215b are located at the corners 12, the rigidity of the frame 210 can be increased, and the natural frequency of the frame 210 can be made higher. Since the rib 215 is a convex portion formed on the frame 210, it can be easily formed, and the manufacturing cost of the motor 1 can be suppressed to a low level.

[0125] Furthermore, the extending direction of the ribs may also be the direction toward the rotating shaft 2. In addition, the number of ribs may be different from the above. The ribs extending in the circumferential direction may include ribs extending in the circumferential direction in addition to the ribs extending in the longitudinal direction as described above.

[0126] Fig.15 This is a perspective view showing a frame 310 according to another modified example of the present embodiment.

[0127] exist Fig.15 In the frame 310 shown, four ribs 315 are provided on each of the four plane portions 11. The four ribs 315 are arranged at substantially equal intervals in the direction of the rotation axis. Each rib 315 extends radially from the inner circumferential surface 10b of the frame 310 toward the inner side of the frame 310. That is, each rib 315 protrudes inward from the inner circumferential surface 10b of the frame 310.

[0128] Each rib 315 extends in the circumferential direction. In this modified example, the ends 315a and 315b of each rib 315 are provided at the corner portion 12. That is, one end 315a of the rib 315 is provided at one corner portion 12 adjacent to the plane portion 11 where each rib 315 is provided. In addition, the other end 315b of the rib 315 is provided at the other corner portion 12.

[0129] Each rib 315 is a recessed portion formed on the frame 310. That is, the portion where each rib 315 is provided is recessed in the outer peripheral surface of the frame 310. The rib 315 can be provided by performing press working or the like on a metal plate constituting the frame 310.

[0130] Even in the frame 310 formed with such ribs 315 , similarly to the frame 210 described above, the natural frequency can be increased and the generation of abnormal noise in the motor 1 can be suppressed.

[0131] In addition, a reinforcing member formed of a member different from the frame may be provided on the frame instead of the ribs 215 and 315, or a frame having a reinforcing member may be used. The reinforcing member may be provided on the plane portion of the frame in a manner extending in the radial direction in the same manner as the ribs. Even by providing such a reinforcing member, the natural frequency of the frame can be increased, and the occurrence of abnormal noise in the motor 1 can be suppressed.

[0132] Fig.16 It is a perspective view for explaining the structure of an actuator 501 according to another modification example of the present embodiment.

[0133] A reinforcing member or rib may be provided in the actuator 501 configured using the motor 1 according to the present embodiment or its modified example, other motors, etc. The reinforcing member or rib is a biasing device for biasing the frame of the motor.

[0134] For example, in Fig.16 In FIG. 5 , for an actuator 501 having a motor 1, the mounting structure of the motor 1 relative to the housing 503 of the actuator 501 is shown. Fig.16 In the figure, except for the case 503 and the motor 1, the components of the actuator 501 (for example, gears, screws, etc.) are omitted from the illustration.

[0135] The housing 503 of the actuator 501 is provided with a housing 510 for the motor 1. The motor 1 is housed in the housing 510 and mounted on the housing 503 of the actuator 501.

[0136] The housing portion 510 is provided with two corner portions 512 and a plane portion (as an example of a surface portion) 511 located between two adjacent corner portions 512. The corner portions 512 and the plane portion 511 have shapes corresponding to the shape of the frame 10 of the motor 1.

[0137] For example, four ribs 515 are provided in the plane portion 511. The four ribs 515 are arranged substantially at equal intervals from each other in the direction of the rotation axis. The ribs 515 extend in a direction substantially perpendicular to the plane portion 511. That is, the ribs 515 extend in the radial direction of the motor 1 arranged in the accommodation portion 510. The ribs 515 extend in the circumferential direction relative to the motor 1 arranged in the accommodation portion 510.

[0138] Each rib 515 extends in the circumferential direction. In this modified example, the ends 515a and 515b of each rib 515 are provided at the corner portion 512. That is, one end 515a of the rib 515 is provided at a corner portion 512 adjacent to the plane portion 511 where each rib 515 is provided. In addition, the other end 515b of the rib 515 is provided at the other corner portion 512.

[0139] Fig.17 2 is a cross-sectional view of the receiving portion 510 perpendicular to the rotation axis 2 .

[0140] like Fig.17 As shown in FIG. 1 , in this modification, the motor 1 is contained in the containing portion 510 by being sandwiched between two members constituting the box body 503 of the actuator 501. In the containing portion 510, two planar portions 511 ( Fig.17 The ribs 515 of the left and right plane portions 511 extend in the radial direction relative to the motor 1. The ribs 515 contact the outer peripheral surface of the plane portion 11 of the frame 10 of the motor 1, and apply force to the plane portion 11 toward the inside of the motor 1.

[0141] In this way, since the frame 10 of the motor 1 is urged by the ribs 515, the vibration of the frame 10 is suppressed by the ribs 515. Therefore, the occurrence of abnormal noise in the motor 1 and the actuator 501 can be suppressed.

[0142] Since the rib 515 extends in the circumferential direction relative to the motor 1 and the ends 515a and 515b are located at the corners 512, the rigidity of the accommodating portion 510 of the case 503 can be increased. Therefore, the frame 10 can be reliably applied, and the vibration of the motor 1 can be more reliably suppressed.

[0143] Moreover, the rib 515 is formed of resin, for example. The rib 515 is a convex portion formed when the housing 503 is formed. Since the rib 515 can be easily formed, the manufacturing cost of the motor 1 can be suppressed to be low. Instead of the rib 515, a reinforcing member formed by a member different from the housing 503 can be provided in the housing 510 of the housing 503. The reinforcing member can be provided on the plane portion 511 of the housing 510 in a manner extending in the radial direction of the motor 1 in the same manner as the rib 515. Even if such a reinforcing member is provided, the vibration of the motor 1 can be suppressed, and the generation of abnormal noise in the motor 1 and the actuator 501 can be suppressed. In addition, instead of the rib 515, the transmission of vibration can be suppressed by a rib formed between a plurality of recesses of the housing 503. In this case, a plurality of recesses and the ribs are arranged in parallel in the direction of the rotation axis in the housing 503. In addition, the transmission of vibration can be suppressed by a rib formed between a plurality of recesses together with the rib 515.

[0144] [other]

[0145] The components of the above-mentioned embodiments and variations can also be combined to form a motor or an actuator. As long as a gap extending in the circumferential direction is provided between the inner circumference of the frame and the outer circumference of the magnet as described above, and adhesive is arranged on both sides of the gap, the occurrence of abnormal noise can be suppressed in the same manner as described above.

[0146] In each of the frame, the magnet and the receiving portion, the plane portion may not be flat but may be a convex portion, a concave portion or slightly curved. A curved surface with a larger radius of curvature than a corner portion may be referred to as a plane portion.

[0147] In the above embodiment, the cross-sectional shape of the motor perpendicular to the rotating shaft is roughly square, but it is not limited to this. For example, in a hexagonal or octagonal motor, as long as a gap extending in the circumferential direction is provided between the inner circumferential surface of the frame and the outer circumferential surface of the magnet as described above, and an adhesive is arranged on both sides of the gap, the occurrence of abnormal noise can be suppressed in the same manner as described above. In addition, even in a cylindrical motor with a cylindrical frame, the same effect as described above can be obtained.

[0148] The motor is not limited to the brushed DC motor described above. By using the same configuration as in the above embodiment in various types of motors (such as brushless motors), the generation of abnormal noise of the motor can be suppressed.

[0149] The above embodiments are to be understood in all respects as illustrative rather than restrictive. The scope of the present invention is indicated by the claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. An actuator comprising: A motor, and a housing having a housing for the motor, The motor comprises: a frame having a plurality of corners and a face portion located between two adjacent corners; and one or more magnets disposed inside the frame. In the direction of the rotation axis, the magnet and the frame are bonded by an adhesive. The plurality of corners are provided with magnetic pole units of the one or more magnets. In the frame, one or more reinforcing members extending in the circumferential direction are provided along the face of the frame, The reinforcing member extends in a radial direction between the frame and the receiving portion, The reinforcing member is formed of a member different from a member forming the frame, The receiving portion has a plurality of corners and a face portion located between two adjacent corners. One or more ribs are provided on the surface of the receiving portion. The one or more ribs extend in a circumferential direction relative to the motor disposed in the accommodation portion.

2. An actuator having: A motor, and a housing having a housing for the motor, The motor comprises: a frame having a plurality of corners and a face portion located between two adjacent corners; and one or more magnets disposed inside the frame. The plurality of corners are provided with magnetic pole units of the one or more magnets. In the frame, one or more reinforcing members extending in the circumferential direction are provided along the face of the frame, The reinforcing member extends in a radial direction between the frame and the receiving portion, The reinforcing member is formed of a member different from a member forming the frame, The receiving portion has a plurality of corners and a face portion located between two adjacent corners. One or more ribs are provided on the surface of the receiving portion. The one or more ribs extend in a circumferential direction of the motor disposed in the accommodation portion.

3. An actuator having: A motor, and a housing having a housing for the motor, The motor comprises: a frame having a plurality of corners and a plurality of face portions; one or more magnets arranged on the inner side of the frame, The plurality of corners are provided with magnetic pole units of the one or more magnets. The plurality of face portions are respectively located between two adjacent corner portions among the plurality of corner portions, When the motor is running, The following vibrations occur in the frame: radially opposite parts of the frame vibrate in opposite directions to each other, adjacent parts of the frame vibrate in opposite directions, and nodes are formed at corners of the frame, and the plurality of faces become antinodes. In the frame, one or more reinforcing members extending in the circumferential direction are provided along the face of the frame, The reinforcing member extends in a radial direction between the frame and the receiving portion, The reinforcing member is formed of a member different from a member forming the frame, The receiving portion has a plurality of corners and a face portion located between two adjacent corners. One or more ribs are provided on the surface of the receiving portion. The one or more ribs extend in the circumferential direction relative to the motor disposed in the accommodation portion.

4. An actuator according to any one of claims 1 to 3, wherein: The plurality of face portions of the frame are a plurality of planar portions.

5. An actuator according to claim 2 or 3, wherein: The magnet and the frame are bonded to each other in the rotation axis direction by an adhesive.

6. An actuator according to any one of claims 1 to 3, wherein: Reinforcing members extending in the circumferential direction are provided at corners and surface portions of the frame.

7. An actuator according to any one of claims 1 to 3, wherein: The plurality of reinforcing members are arranged on the frame, The plurality of ribs are arranged on the box body, The plurality of ribs urge a face portion of the frame toward an interior portion of the motor.

8. An actuator according to any one of claims 1 to 3, wherein: The end portions of the one or more ribs are provided at corners of the accommodation portion.

9. An actuator according to any one of claims 1 to 3, wherein: The one or more ribs are formed as protrusions or between the plurality of recesses of the box body.

10. An actuator according to any one of claims 1 to 3, wherein: The plurality of reinforcing members are arranged on the frame, The plurality of ribs are arranged on the box body, The plurality of reinforcing members and the plurality of ribs are arranged on an end side of the frame with respect to a central portion of the face portion of the frame.

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