motor

Abstract

The problem addressed by this disclosure is to shorten the axial length of the rotating shaft in a motor. [Solution] The motor 1 comprises a rotating shaft 2, a seal portion 3, a bearing (first bearing 4), and a fixing member 5. The rotating shaft 2 rotates about the axis Ax1. The seal portion 3 is provided along the circumferential direction of the rotating shaft 2. The bearing is provided along the circumferential direction of the rotating shaft 2 and rotatably supports the rotating shaft 2. The fixing member 5 fixes the bearing by pressing it along the axial direction of the rotating shaft 2. At least a portion of the fixing member 5 overlaps with the seal portion 3 when viewed from the radial direction of the rotating shaft 2. When viewed from the axial direction of the rotating shaft 2, the fixing member 5 is positioned on the opposite side of the axis Ax1 from the seal portion 3 along the radial direction of the rotating shaft 2.

Description

Technical Field

[0001] The present disclosure generally relates to motors, and more specifically relates to a motor including a rotating shaft.

Background Art

[0002] Conventionally, as a motor, the motor (driving device) disclosed in Patent Document 1 is known.

[0003] The motor described in Patent Document 1 includes: a shaft (rotating shaft) fixed to a rotor and rotating together with the rotor; a first bearing that rotatably supports the shaft; a second bearing that rotatably supports the shaft; a seal member in sliding contact with the outer periphery of the shaft; and a biasing member (fixing member) that biases the outer ring of the second bearing.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0005] By the way, in a motor with the above configuration, components are arranged along the axial direction of the shaft (rotating shaft), so there is a problem that the length of the motor along the axial direction of the shaft (rotating shaft) becomes long.

[0006] The present disclosure has been made in view of the above problems, and an object of the present disclosure is to provide a motor capable of further shortening the length of the motor along the axial direction of the rotating shaft.

Means for Solving the Problem

[0007] A motor according to one aspect of the present disclosure comprises a rotating shaft, a seal portion, a bearing, and a fixing member. The rotating shaft rotates about an axis. The seal portion is provided along the circumferential direction of the rotating shaft. The bearing is provided along the circumferential direction of the rotating shaft and rotatably supports the rotating shaft. The fixing member fixes the bearing by pressing it along the axial direction of the rotating shaft. At least a portion of the fixing member overlaps with the seal portion when viewed from the radial direction of the rotating shaft. When viewed from the axial direction, the fixing member is positioned radially with respect to the seal portion on the side opposite to the axis. [Effects of the Invention]

[0008] According to this disclosure, the length of the rotating shaft in the motor along the axial direction can be made shorter. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a perspective view of the motor according to this embodiment. [Figure 2] Figure 2 is a cross-sectional view of the motor shown above. [Figure 3] Figure 3 is a cross-sectional view of the motor according to Modification 1. [Figure 4] Figure 4 is a cross-sectional view of the motor according to modified example 2. [Figure 5] Figure 5 is a cross-sectional view of the motor according to Modification 3. [Modes for carrying out the invention]

[0010] The embodiments and modifications described below are merely examples of the present disclosure, and the present disclosure is not limited to these embodiments and modifications. Various modifications are possible depending on the design, etc., as long as they do not depart from the technical concept of the present disclosure.

[0011] The figures described in this disclosure are schematic diagrams, and the ratios of the size and thickness of each component in each figure do not necessarily reflect the actual dimensional ratios. Furthermore, the arrows indicating directions in the drawings are examples only and are not intended to specify the direction in which motor 1 is used. Also, the arrows indicating directions in the drawings are for illustrative purposes only and do not represent actual dimensions.

[0012] (Embodiment) Hereinafter, the motor 1 according to this embodiment will be described with reference to Figures 1 and 2.

[0013] (1) Overview As shown in Figure 2, the motor 1 according to this embodiment comprises a rotating shaft 2, a seal portion 3, a bearing (first bearing 4), and a fixing member 5. The rotating shaft 2 rotates about the axis Ax1. The seal portion 3 is provided along the circumferential direction of the rotating shaft 2. The bearing (first bearing 4) is provided along the circumferential direction of the rotating shaft 2 and rotatably supports the rotating shaft 2. The fixing member 5 fixes the bearing (first bearing 4) by pressing it along the axial direction of the rotating shaft 2. At least a part of the fixing member 5 overlaps with the seal portion 3 when viewed from the radial direction of the rotating shaft 2. When viewed from the axial direction of the rotating shaft 2, the fixing member 5 is positioned on the opposite side of the axis Ax1 from the seal portion 3 along the radial direction of the rotating shaft 2.

[0014] With this configuration, by arranging some of the components of motor 1 and other components of motor 1 to overlap when viewed from the radial direction of the rotation shaft 2, the length of motor 1 along the axial direction of the rotation shaft 2 can be made shorter.

[0015] (2) Composition As shown in Figure 2, the motor 1 according to this embodiment comprises a rotating shaft 2, a seal portion 3, a first bearing 4, and a fixing member 5. Furthermore, as shown in Figure 1, the motor 1 comprises a case 6. In addition, as shown in Figure 2, the motor 1 comprises a coil 71, a stator 72, a plurality of magnets 73, a rotor 74, a second bearing 8, and a cover 9.

[0016] The motor 1 is, for example, a motor used in an electric power steering system of a vehicle. The motor 1 transmits rotational torque to and drives a load of industrial machinery such as conveying machines or machine tools, or robots. Electric power is supplied to the motor 1 from, for example, a control device (not shown).

[0017] (2.1) Rotating shaft The rotating shaft 2 is formed in a cylindrical shape. Further, as shown in Fig. 2, the rotating shaft rotates around the axial center Ax1. Furthermore, the rotating shaft 2 is fixed to a rotor 74. That is, when the rotor 74 is rotated by a plurality of magnets 73, the rotating shaft 2 rotates together with the rotor 74 around the axial center Ax1.

[0018] As shown in Fig. 1 and Fig. 2, a tip end portion 23 of the rotating shaft 2 is inserted through a shaft hole 62 described later along the axial direction of the rotating shaft 2, and protrudes from a case 6. Further, the tip end portion 23 propagates the rotational torque generated by the motor 1 to an object connected to the tip end portion 23.

[0019] As shown in Fig. 2, the rotating shaft 2 has a first portion 21 and a second portion 22. The first portion 21 and the second portion 22 are connected to each other along the axial direction.

[0020] The first portion 21 is a portion of the rotating shaft 2 where at least a part of the first portion 21 is in contact with a seal portion 3 (a seal member 3a) (see Fig. 2). In the first portion 21, a first side surface portion 24 is provided on a side surface along the circumferential direction of the rotating shaft 2. Further, as shown in Fig. 2, the first portion 21 is formed closer to the tip end portion 23 of the rotating shaft 2 than the second portion 22 is.

[0021] The second portion 22 is the portion of the rotating shaft 2 that, at least a part of, contacts the first bearing 4. Specifically, the second portion 22 is the portion of the rotating shaft 2 that, at least a part of, contacts the inner ring 41 of the first bearing 4 (see Figure 2). The second portion 22 is provided with a second side surface portion 25 that contacts the inner ring 41, which is part of the side surface along the circumferential direction of the rotating shaft 2. When viewed from the axial direction, the second portion 22 protrudes from the first portion 21 along the radial direction of the rotating shaft 2.

[0022] In other words, as shown in Figure 2, the diameter of the cross-section of the second part 22, which is cut in a direction perpendicular to the axial direction of the rotation axis 2, is longer than the diameter of the cross-section of the first part 21, which is cut in a direction perpendicular to the axial direction of the rotation axis 2.

[0023] (2.2) Seal part The seal portion 3 is provided along the circumferential direction of the rotating shaft 2. In this embodiment, the seal portion 3 is a hollow cylindrical seal member 3a. The seal member 3a is a member that prevents components housed in the case 6 from being immersed in oil. The seal member 3a is, for example, an oil seal.

[0024] As shown in Figure 2, the sealing member 3a is fitted between the first side portion 24 and the third side portion 65 (described later) in a manner that allows the rotating shaft 2 to rotate. Furthermore, the space between the sealing member 3a and the first side portion 24 and the third side portion 65 is formed in such a way that at least oil cannot enter.

[0025] Furthermore, it is preferable that the length of the sealing member 3a along the axial direction of the rotating shaft 2 be shorter than the length of the third side portion 65 along the axial direction of the rotating shaft 2.

[0026] (2.3) First bearing The first bearing 4 (bearing) is provided along the circumferential direction of the rotating shaft 2 and rotatably supports the rotating shaft 2. The first bearing 4 is, for example, a bearing. In this embodiment, the first bearing 4 is formed along the second side surface portion 25 of the second portion 22 of the rotating shaft 2.

[0027] The first bearing 4 is positioned so as to be sandwiched between the second side surface portion 25 of the second part 22 and the inner side surface portion 66 of the first protrusion 63, which will be described later and is provided on the frame 60 (see Figure 2).

[0028] Furthermore, the first bearing 4 has an inner ring 41, a plurality of steel balls 42, and an outer ring 43.

[0029] The inner ring 41 has a circular inner circumference when viewed from the axial direction of the rotating shaft 2. The inner ring 41 is positioned to contact the second side surface 25 of the rotating shaft 2 along its circumferential direction. Furthermore, grooves are formed on the outer circumference of the inner ring 41 along the circumferential direction of the rotating shaft 2 to accommodate multiple steel balls 42 (see Figure 2). Additionally, the inner diameter of the inner ring 41 is greater than the outer diameter of the sealing member 3a.

[0030] The outer ring 43 is formed in a hollow cylindrical shape and is provided along the circumferential direction of the rotation shaft 2. Furthermore, the outer ring 43 is provided on the opposite side of the rotation shaft 2 from the inner ring 41. As shown in Figure 2, the outer ring 43 faces the inner surface portion 66 of the first projection 63 so as to be in contact with the rotation shaft 2 along its radial direction. A groove is formed along the circumferential direction of the rotation shaft 2 on the inner circumference of the outer ring 43, allowing for the fitting of multiple steel balls 42 (see Figure 2). Additionally, the outer diameter of the outer ring 43 is greater than the outer diameter of the sealing member 3a.

[0031] As shown in Figure 2, the multiple steel balls 42 are arranged so as to be sandwiched between a groove formed on the outer circumference of the inner ring 41 along the circumferential direction of the rotation axis 2 and a groove formed on the inner circumference of the outer ring 43 along the circumferential direction of the rotation axis 2.

[0032] (2.4) Fixing members The fixing member 5 is, for example, a corrugated washer. The fixing member 5 fixes the first bearing 4 by pressing it along the axial direction of the rotating shaft 2. More specifically, the fixing member 5 fixes the first bearing 4 by pressing its outer ring 43 along the axial direction of the rotating shaft 2. In addition, the fixing member 5 prevents gaps from forming between the inner ring 41 and the outer ring 43 and the steel ball 42 by pressing the outer ring 43 along the axial direction of the rotating shaft 2. The fixing member 5 has a hollow portion formed along the axial direction of the rotating shaft 2. Furthermore, the hollow portion is formed so that the sealing member 3a passes through along the axial direction of the rotating shaft 2. As shown in Figure 2, the fixing member 5 is positioned in the case groove 64 of the first bearing 4 (bearing), which will be described later, along the axial direction of the rotating shaft 2.

[0033] At least a portion of the fixing member 5 overlaps with the sealing member 3a when viewed from the radial direction of the rotation axis 2. Furthermore, when viewed from the axial direction of the rotation axis 2, the fixing member 5 is positioned relative to the sealing member 3a along the radial direction of the rotation axis 2, on the opposite side from the axis Ax1.

[0034] (2.5) Coil, stator, multiple magnets, rotor The coil 71 is a winding made of, for example, copper or a copper alloy. The coil 71 is formed by winding a conductor around the teeth 721 of the stator 72, which will be described later.

[0035] The stator 72 is made of a magnetic material such as iron. The stator 72 is formed in a hollow cylindrical shape. The stator 72 has a plurality of teeth 721. The teeth 721 protrude from the inner circumference of the stator 72 toward the rotation axis 2. Also, as shown in Figure 2, the stator 72 is formed along the radial direction of the rotation axis 2 on the opposite side of the rotor 74 from the rotation axis 2. For example, when power is supplied from the control device and current flows through the coil 71, the stator 72 generates a rotating magnetic field that rotates the rotor 74.

[0036] The multiple magnets 73 are permanent magnets, such as neodymium magnets. The multiple magnets 73 are fitted into the rotor 74 so that their north and south poles are arranged alternately at equal intervals.

[0037] The rotor 74 is made of a magnetic material such as iron. The rotor 74 is formed in a hollow cylindrical shape. As shown in Figure 2, multiple magnets 73 are fitted into the rotor 74 at equal intervals. The rotor 74 rotates in response to the rotating magnetic field generated by the stator 72 because of the multiple magnets 73 fitted into it.

[0038] (2.6) Case Case 6 houses at least the seal portion 3 (seal member 3a), the first bearing 4 (bearing), and the fixing member 5. Specifically, as shown in Figure 2, Case 6 houses the seal member 3a, the first bearing 4, the fixing member 5, the coil 71, the stator 72, the multiple magnets 73, the rotor 74, and the second bearing 8. Furthermore, Case 6 houses a portion of the rotating shaft 2. Here, as shown in Figure 1, Case 6 protects the components it houses.

[0039] Furthermore, case 6 comprises a frame 60 and a frame cover 61. Note that the frame 60 and frame cover 61 may be integrally molded as case 6.

[0040] (2.6.1) Frame The frame 60 is made of, for example, aluminum. The frame 60 has an axial hole 62, a first projection 63, and a case groove 64.

[0041] As shown in Figure 2, the tip portion 23 of the rotating shaft 2 is inserted through the shaft hole 62 along the axial direction of the rotating shaft 2. The shaft hole 62 also has a third side portion 65 and a fourth side portion 651 facing the rotating shaft 2 along the radial direction of the rotating shaft 2. The diameter of the third side portion 65 is longer than the diameter of the fourth side portion 651. Furthermore, the third side portion 65 of the shaft hole 62 sandwiches the sealing member 3a between the first side portion 24 and the third side portion 65. That is, the sealing member 3a is sandwiched between the first side portion 24 and the third side portion 65.

[0042] As shown in Figure 2, the first projection 63 protrudes from the inner surface of the frame 60 along the axial direction of the rotating shaft 2. Furthermore, the first projection 63 protrudes so as to contact the outer ring 43 of the first bearing 4. Additionally, the diameter of the first projection 63 is greater than the diameter of the third side surface 65.

[0043] The case groove 64 is formed by a first projection 63 and a second projection 652 including a third side portion 65. The case groove 64 is a groove for positioning the fixing member 5.

[0044] By positioning the fixing member 5 in the case groove 64, in this embodiment, the fixing member 5 presses the outer ring 43 along the axial direction of the rotating shaft 2, thereby preventing gaps from forming between the inner ring 41 and the outer ring 43 and the multiple steel balls 42.

[0045] (2.6.2) Frame cover The frame cover 61 is made of, for example, aluminum. The frame cover 61 is formed in a hollow cylindrical shape. The frame cover 61 has a third projection 67.

[0046] As shown in Figure 2, the third projection 67 protrudes from the inner circumferential surface of the frame cover 61 along the axial direction of the rotating shaft 2. The third projection 67 also protrudes so as to be in contact with the outer ring 83 of the second bearing 8.

[0047] (2.7) Cover Cover 9 is formed to protect the frame cover 61, as shown in Figures 1 and 2. Cover 9 houses a control circuit (not shown). That is, the control circuit is located in the space formed by cover 9 and frame cover 61.

[0048] (2.8) Second bearing The second bearing 8 is provided along the circumferential direction of the rotating shaft 2 and rotatably supports the rotating shaft 2. The second bearing 8 is, for example, a bearing. In this embodiment, the second bearing 8 is formed along the outer circumference of the rotating shaft 2. That is, the second bearing 8 is positioned to be sandwiched between the outer circumference 26 and the third projection 67, which are provided at the end opposite the tip 23 at both ends of the rotating shaft 2 along its axial direction.

[0049] The second bearing 8 also has an inner ring 81, a plurality of steel balls 82, and an outer ring 83.

[0050] The inner ring 81 has a circular inner circumference when viewed from the axial direction of the rotating shaft 2. Furthermore, the inner ring 81 is positioned to contact the outer circumference 26 of the rotating shaft 2 along its circumferential direction (see Figure 2). Additionally, grooves are formed on the outer circumference of the inner ring 81 along the circumferential direction of the rotating shaft 2 to accommodate multiple steel balls 82.

[0051] The outer ring 83 is formed in a hollow cylindrical shape and is provided along the circumferential direction of the rotation shaft 2. Furthermore, the outer ring 83 is provided on the opposite side of the rotation shaft 2 from the inner ring 81. As shown in Figure 2, the outer ring 83 faces the inner circumferential surface 68 of the third projection 67 so as to be in contact with the rotation shaft 2 along its radial direction. A groove is formed along the circumferential direction of the rotation shaft 2 on the inner circumference of the outer ring 83, allowing for the fitting of multiple steel balls 82 (see Figure 2).

[0052] As shown in Figure 2, the multiple steel balls 82 are arranged so as to be sandwiched between a groove formed on the outer circumference of the inner ring 81 along the circumferential direction of the rotation axis 2 and a groove formed on the inner circumference of the outer ring 83 along the circumferential direction of the rotation axis 2.

[0053] (3) Advantages As described above, the motor 1 according to this embodiment, as shown in Figure 2, comprises a rotating shaft 2, a seal portion 3, a first bearing 4, and a fixing member 5. The rotating shaft 2 rotates about the axis Ax1. The seal portion 3 is provided along the circumferential direction of the rotating shaft 2. The first bearing 4 is provided along the circumferential direction of the rotating shaft 2 and rotatably supports the rotating shaft 2. The fixing member 5 fixes the first bearing 4 by pressing it along the axial direction of the rotating shaft 2. At least a part of the fixing member 5 overlaps with the seal portion 3 when viewed from the radial direction of the rotating shaft 2. When viewed from the axial direction of the rotating shaft 2, the fixing member 5 is positioned on the opposite side of the axis Ax1 from the seal portion 3 along the radial direction of the rotating shaft 2.

[0054] With this configuration, by arranging some parts of one component to overlap with other components when viewed from the radial direction of the rotation axis 2, the components do not take up much space along the axial direction of the rotation axis 2, thus making the length of the motor 1 along the axial direction of the rotation axis 2 shorter.

[0055] (4) Variations (modified version) The following are examples of modifications. These modifications can be applied in appropriate combinations with the above-described embodiments.

[0056] (4.1) Variation 1 In the above embodiment, as shown in Figure 2, the seal portion 3 (seal member 3a) and the first bearing 4 are configured not to overlap when viewed from the radial direction of the rotating shaft 2, but the configuration is not limited to this. As shown in the motor 1A in Figure 3, the seal member 3a and the first bearing 4 may overlap when viewed from the radial direction of the rotating shaft 2.

[0057] As shown in Figure 3, the sealing member 3a and the first bearing 4 overlap when viewed from the radial direction of the rotating shaft 2, which allows the length of the rotating shaft 2 in the motor 1A along the axial direction to be shortened.

[0058] Here, by overlapping the seal member 3a and the first bearing 4 when viewed from the radial direction of the rotating shaft 2, the length of the motor 1 along the axial direction of the rotating shaft 2 can be made shorter even if the length of the seal member 3a along the axial direction of the rotating shaft 2 is increased. By increasing the length of the seal member 3a along the axial direction of the rotating shaft 2, the effect of suppressing oil contamination of the seal member 3a can be further enhanced.

[0059] (4.2) Modification 2 In the above embodiment, as shown in Figure 2, nothing is attached to the tip 23 of the rotating shaft 2, but the configuration is not limited to this. A reduction gear 10 may be attached to the tip 23 of the rotating shaft 2, as shown in the motor 1B in Figure 4. That is, the motor 1B may further include a reduction gear 10, as shown in Figure 4.

[0060] The reduction gear 10 includes an output shaft 11, a reduction gear 12, a reduction gear cover 13, and a gear hole 111.

[0061] As shown in Figure 4, the reducer cover 13 houses the reduction gear 12. The reducer cover 13 also protects the reduction gear 12.

[0062] The output shaft 11 is the shaft through which the rotating shaft 2 outputs force via the reduction gear 12. The tip of the output shaft 11 protrudes from the reduction gear cover 13 along the axial direction of the rotating shaft 2. The output shaft 11 rotates around the axis Ax1. However, the rotation center of the output shaft 11 does not have to be the axis Ax1.

[0063] The gear hole 111 is used when mounting the reduction gear 10 to the tip 23 of the rotating shaft 2, and the tip 23 of the rotating shaft 2 is fitted into it along the axial direction of the rotating shaft 2. The gear hole 111 is also formed so that the output shaft 11 rotates around the axis Ax1.

[0064] The reduction gear 12 reduces the rotation speed of the rotating shaft 2 before the reduction gear 10 is installed by fitting the tip 23 of the rotating shaft 2 into the gear hole 111, and this reduction is reflected in the rotation speed of the output shaft 11. Also, by using the reduction gear 12, the rotation speed of the output shaft 11 becomes slower than the rotation speed of the rotating shaft 2 before the reduction gear 10 is installed. However, the torque force of the output shaft 11 becomes stronger than the torque force of the rotating shaft 2 before the reduction gear 10 is installed. Here, torque force refers to the force that rotates an object.

[0065] (4.3) Modification 3 In the above embodiment, the sealing portion 3 is configured as a sealing member 3a formed in the shape of a hollow cylinder, but the configuration is not limited to this. The sealing portion 3 may have a sealing member 3a and a holding portion 69 that holds the sealing member 3a.

[0066] As shown in Figure 5, the retaining portion 69 protrudes toward the rotating shaft 2 from the end of the third side portion 65 along the radial direction of the rotating shaft 2. That is, the retaining portion 69 protrudes toward the rotating shaft 2 from the second protruding portion 652 along the radial direction of the rotating shaft 2. The retaining portion 69 holds the sealing member 3a so that it does not move along the axial direction of the rotating shaft. It is preferable that the retaining portion 69 be formed integrally with the case 6. However, the retaining portion 69 does not necessarily have to be integrally molded with the case 6.

[0067] At least a portion of the holding portion 69 overlaps with the fixing member 5 when viewed from the radial direction of the rotation axis 2. In other words, at least a portion of the fixing member 5 overlaps with the holding portion 69 when viewed from the radial direction of the rotation axis 2. In this case, when viewed from the axial direction of the rotation axis 2, the fixing member 5 is on the opposite side of the axis Ax1 from the holding portion 69.

[0068] (4.4) Modification 4 In the above embodiment, the inner diameter of the inner ring 41 of the first bearing 4 is longer than the outer diameter of the sealing member 3a, but the configuration is not limited to this. The outer diameter of the outer ring 43 of the first bearing 4 may be shorter than the inner diameter of the sealing member 3a.

[0069] In this case, the diameter of the first portion 21 is formed to be longer than the diameter of the second portion 22, and the seal member 3a is positioned on the opposite side of the axis Ax1 from the axis of the first bearing 4, along the radial direction of the rotation shaft 2 when viewed from the axial direction of the rotation shaft 2. Furthermore, the seal member 3a and the first bearing 4 overlap when viewed from the radial direction of the rotation shaft 2. That is, the seal portion 3 and the first bearing 4 overlap when viewed from the radial direction of the rotation shaft 2.

[0070] (4.5) Modification 5 In the above embodiment, the fixing member 5 is configured as a corrugated washer, as shown in Figure 2, but it is not limited to this configuration. The fixing member 5 may also be a coil spring.

[0071] The coil spring used as the fixing member 5 has a hollow portion formed along the axial direction of the rotating shaft 2, and can obtain the same effect as the corrugated washer in the above embodiment.

[0072] (4.6) Variation 6 In the above embodiment, the fixing member 5 is configured as a corrugated washer as shown in Figure 2, but it is not limited to this configuration. The fixing member 5 may be a plurality of leaf springs.

[0073] The fixing member 5 can be configured by using multiple leaf springs as the fixing member 5 and arranging them in the case groove 64 to press the outer ring 43 along the axial direction of the rotating shaft 2, thereby suppressing the formation of a gap between the inner ring 41 and the outer ring 43 and the steel ball 42. In other words, the corrugated washer used as the fixing member 5 in the above embodiment may have a portion cut along the radial direction of the rotating shaft 2.

[0074] (summary) As described above, the motor (1; 1A; 1B; 1C) of the first embodiment comprises a rotating shaft (2), a seal portion (3), a bearing (e.g., a first bearing 4), and a fixing member (5). The rotating shaft (2) rotates about an axis (Ax1). The seal portion (3) is provided along the circumferential direction of the rotating shaft (2). The bearing (e.g., a first bearing 4) is provided along the circumferential direction of the rotating shaft (2) and rotatably supports the rotating shaft (2). The fixing member (5) fixes the bearing (e.g., a first bearing 4) by pressing it along the axial direction of the rotating shaft (2). At least a portion of the fixing member (5) overlaps with the seal portion (3) when viewed from the radial direction of the rotating shaft (2). When viewed from the axial direction of the rotating shaft (2), the fixing member (5) is positioned on the opposite side of the axis (Ax1) from the axis along the radial direction of the rotating shaft (2) relative to the sealing portion (3).

[0075] According to this embodiment, by arranging some of the components and other components to overlap when viewed from the radial direction of the rotation axis (2), the length of the rotation axis (2) in the motor (1; 1A; 1B; 1C) along the axial direction can be made shorter.

[0076] In the motor of the second embodiment (1; 1A; 1B), in the first embodiment, the seal portion (3) is a seal member (3a) formed in the shape of a hollow cylinder. The fixing member (5) has a hollow portion formed along the axial direction. The hollow portion is formed so that the seal member (3a) passes through it along the axial direction.

[0077] According to this embodiment, at least a portion of the sealing member (3a) of the motor (1, 1A, 1B) and the fixing member (5) of the motor (1) can be arranged to overlap when viewed from the radial direction of the rotation shaft (2). In other words, the length of the motor (1; 1A; 1B) along the axial direction of the rotation shaft (2) can be made shorter.

[0078] In the third embodiment of the motor (1; 1A; 1B), as in the second embodiment, the bearing (e.g., the first bearing 4) has an inner ring (41) and an outer ring (43) provided along the circumferential direction of the rotating shaft (2). The outer ring (43) is formed in a hollow cylindrical shape and is provided on the opposite side of the inner ring (41) from the rotating shaft (2). The outer diameter of the outer ring (43) is greater than the outer diameter of the sealing member (3a).

[0079] According to this embodiment, the outer ring (43) and the sealing member (3a) can be arranged to overlap when viewed from the radial direction of the rotating shaft (2). In other words, the length of the rotating shaft (2) in the motor (1; 1A; 1B) along the axial direction can be made shorter.

[0080] In the motor of the fourth embodiment (1;1A;1B), in the third embodiment, the inner circumference of the inner ring (41) is circular when viewed from the axial direction. The inner diameter of the inner ring (41) is longer than the outer diameter of the sealing member (3a).

[0081] According to this embodiment, the inner ring (41) and the sealing member (3a) can be arranged to overlap when viewed from the radial direction of the rotating shaft (2). In other words, the length of the rotating shaft (2) in the motor (1; 1A; 1B) along the axial direction can be made shorter.

[0082] In the motor of the fifth embodiment (1; 1A; 1B), in any of the second to fourth embodiments, at least a portion of the bearing (e.g., the first bearing 4) overlaps with the sealing member (3a) when viewed radially.

[0083] According to this embodiment, by arranging the bearing (for example, the first bearing 4) and the sealing member (3a) to overlap when viewed from the radial direction, the length of the rotating shaft (2) in the motor (1; 1A; 1B) along the axial direction can be made shorter.

[0084] In the sixth embodiment of the motor (1; 1A; 1B), in the third or fourth embodiment, the rotating shaft (2) has a first portion (21) that contacts the sealing member (3a) and a second portion (22) that contacts the inner ring (41). The first portion (21) is formed closer to the tip (23) of the rotating shaft (2) than the second portion (22).

[0085] According to this embodiment, since the first portion (21) is formed closer to the tip (23) of the rotating shaft (2) than the second portion (22), the sealing member (3a) can be positioned closer to the tip (23) of the rotating shaft (2) compared to the inner ring (41).

[0086] In the motor of the seventh embodiment (1;1A;1B), in the sixth embodiment, the second portion (22) protrudes radially from the first portion (21) when viewed from the axial direction.

[0087] According to this embodiment, the inner diameter of the sealing member (3a) can be made shorter than the inner diameter of the inner ring (41).

[0088] In the motor (1C) of the eighth embodiment, in the first embodiment, the seal portion (3) has a seal member (3a) and a retaining portion (69) that holds the seal member (3a). At least a portion of the fixed member (5) overlaps with the retaining portion (69) when viewed from the radial direction. When viewed from the axial direction, the fixed member (5) is positioned on the opposite side of the axis (Ax1) from the retaining portion (69).

[0089] According to this embodiment, the holding portion (69) overlaps with at least a part of the fixing member (5) when viewed from the radial direction, thereby shortening the length of the rotating shaft (2) in the motor (1) along the axial direction.

[0090] In the motor (1C) of the ninth embodiment, the motor further comprises a case (6) that houses at least a sealing member (3a), a bearing (e.g., a first bearing 4), and a fixing member (5), as in the eighth embodiment. The case (6) is provided with a retaining portion (69).

[0091] According to this embodiment, by providing a holding portion (69) in the case (6) for holding the sealing member (3a), the length of the rotating shaft (2) in the motor (1) along the axial direction can be shortened.

[0092] In the motor of the tenth embodiment (1;1A;1B;1C), in the first embodiment, the fixing member (5) is a corrugated washer.

[0093] According to this embodiment, by making the fixing member (5) a corrugated washer, the fixing member (5) presses the outer ring (43) along the axial direction of the rotation shaft (2), thereby preventing a gap from forming between the inner ring (41) and the outer ring (43) and the steel ball (42). [Explanation of Symbols]

[0094] 1,1A,1B,1C motor 2 rotation axes 3. Sealing part 3a Sealing member 5 Fixing members 6 cases 21 Part 1 22 Part 2 23 Tip 41 Inner circle 43 Outer ring 69 Holding part Ax1 axis center

Claims

1. A rotational axis that rotates around its central axis, A sealing portion provided along the circumferential direction of the aforementioned rotating shaft, A bearing that rotatably supports the aforementioned rotating shaft, The system includes a fixing member that fixes the bearing by pressing it along the axial direction of the rotating shaft, The bearing is provided along the circumferential direction of the rotating shaft, At least a portion of the fixing member overlaps with the sealing portion when viewed from the radial direction of the rotation axis. When viewed from the axial direction, the fixing member is positioned radially with respect to the sealing portion on the side opposite to the axis. Motor.

2. The aforementioned sealing portion is a sealing member formed in the shape of a hollow cylinder. The fixing member has a hollow portion formed along the axial direction, The hollow portion is formed so that the sealing member passes through it along the axial direction. The motor according to claim 1.

3. The bearing has an inner ring and an outer ring provided along the circumferential direction of the rotating shaft, The outer ring is formed in a hollow cylindrical shape and is provided on the side opposite to the axis of rotation relative to the inner ring. The outer diameter of the outer ring is longer than the outer diameter of the sealing member. The motor according to claim 2.

4. The inner circumference of the inner ring is circular when viewed from the axial direction. The inner diameter of the inner ring is longer than the outer diameter of the sealing member. The motor according to claim 3.

5. At least a portion of the bearing overlaps with the sealing member when viewed from the radial direction. The motor according to any one of claims 2 to 4.

6. The aforementioned rotating shaft is The first portion that contacts the sealing member, It has a second portion that contacts the inner ring, The first portion is formed closer to the tip of the rotation axis than the second portion. The motor according to claim 3 or 4.

7. The second portion, when viewed from the axial direction, protrudes from the first portion along the radial direction. The motor according to claim 6.

8. The aforementioned sealing portion is sealing member and It has a holding portion for holding the sealing member, At least a portion of the fixing member overlaps with the holding portion when viewed from the radial direction. The fixing member, when viewed from the axial direction, is positioned on the opposite side of the axis from the holding portion. The motor according to claim 1.

9. The device further comprises a case that houses at least the sealing member, the bearing, and the fixing member, The case is provided with the holding portion. The motor according to claim 8.

10. The aforementioned fixing member is a corrugated washer. The motor according to claim 1.

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