Seal structure and motor

Abstract

The sealing structure includes a partition member (20) that separates the first space (S1) and the second space (S2) between the first space (S1) and the second space (S2) that are arranged side by side, a first member (10) that partitions the first space (S1), a second member (30) that partitions the second space (S2), a first packing portion (41) that seals the first space (S1) between the first member (10) and the partition member (20), and a second packing portion (42) that seals the second space (S2) between the second member (30) and the partition member (20). The first packing portion (41) and the second packing portion (42) are integrally formed as a single packing (40) and are attached to the partition member (20).

Description

[Technical Field]

[0001] The present invention relates to a seal structure and a motor to which the seal structure is applied. [Background technology]

[0002] Conventionally, one known sealing structure is one in which a partition member that partitions a space that houses a component and has an opening or hole and seals the space with a sealing member provided between the partition member and a lid member that closes the opening of the partition member. For example, Patent Document 1 discloses a structure in which a sealing member seals between a case (partition member) that houses a reduction mechanism and a cover (lid member) that closes the opening of the case. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6795358 Summary of the Invention [Problem to be solved by the invention]

[0004] As described above, the sealing structure disclosed in Patent Document 1 is a structure in which a single space is sealed by a sealing member provided between a case and a cover. However, there are cases in which a sealing structure is required to seal both of two spaces arranged side by side. For example, this is the case when the above-mentioned partitioning members are arranged side by side with the above-mentioned lid member sandwiched between them. In this case, the sealing structure disclosed in Patent Document 1 requires a new sealing member to seal between the partitioning member (case) and the lid member (cover) that separate one of the two spaces, in addition to the sealing member that seals between the partitioning member and the lid member that separates the other of the two spaces, which results in an increase in the number of parts.

[0005] The present invention has been devised in view of the above-mentioned problems, and one of its objects is to provide a seal structure that can seal both of two parallel spaces while suppressing an increase in the number of parts, and a motor to which said seal structure is applied. However, this object is not limited to this object. Another object of the present invention is to achieve effects that cannot be obtained by conventional techniques, which are derived from the configurations shown in the below-mentioned embodiments. [Means for solving the problem]

[0006] The disclosed seal structure and motor can be realized as the following disclosed aspects (application examples), which solve at least some of the above problems.

[0007] Aspect 1. The disclosed seal structure includes a partition wall member separating a first space and a second space arranged side by side, a first member partitioning the first space, a second member partitioning the second space, a first packing portion sealing the first space between the first member and the partition wall member, and a second packing portion sealing the second space between the second member and the partition wall member. The first packing portion and the second packing portion are integrally formed as a single packing and are attached to the partition wall member. The packing is formed integrally with the partition member by outsert molding and has an annular shape surrounding an axis extending in a direction in which the first space and the second space are arranged side by side. The partition member is provided with second through holes drilled in the direction in which the first space and the second space are arranged at radial positions shifted from radial positions centered on the axes of the first packing portion and the second packing portion, and the packing is provided with anchor portions that engage with the second through holes and connecting portions that connect the anchor portions to one of the first packing portion and the second packing portion in the radial direction.

[0008] Aspect 2. The disclosed motor includes a cylindrical housing with a bottom, a rotor and a stator housed in the housing, a shaft that rotates integrally with the rotor, a bearing that rotatably supports the shaft, and an end bell that closes an opening in the housing and is disposed opposite a housing of a driven device disposed on the opening side of the housing. The end bell has a housing portion that houses the bearing radially inside the housing and centered on the axis of the shaft. In the motor, the seal structure described in Aspect 1 above is applied to the end bell as the partition member, the housing as the first member, and the housing as the second member. [Effects of the Invention]

[0009] According to the disclosed seal structure and motor, it is possible to seal both of the two spaces arranged side by side while suppressing an increase in the number of parts. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is an axial cross-sectional view showing a motor to which a seal structure according to an embodiment is applied and a main part of a driven device driven by the motor. [Figure 2] 2 is a perspective view of the motor of FIG. 1 as viewed from the first axial direction side. [Figure 3] 2 is a perspective view of an end bell and a packing provided in the motor of FIG. 1, as viewed from the first axial direction side. [Figure 4] 2 is a plan view of the motor of FIG. 1 as viewed from the second axial direction side. [Figure 5] 4 is a partial axial cross-sectional view of an end bell and a packing included in the motor of FIG. 1 (a view corresponding to the cross-sectional view taken along the arrow XX in FIG. 4). [Figure 6] 1. FIG. 4 is a partial axial cross-sectional view of an end bell and a packing included in the motor of FIG. [Figure 7] 2 is a perspective view of a packing included in the motor of FIG. 1, as viewed from the first axial direction side. DETAILED DESCRIPTION OF THE INVENTION

[0011] A seal structure and a motor according to an embodiment will be described with reference to the drawings. The embodiments described below are merely examples, and are not intended to exclude various modifications and applications of techniques not explicitly described in the following embodiments. The configurations of the present embodiments can be modified in various ways without departing from the spirit of the embodiments.

[0012] The seal structure of the embodiment seals both a first space and a second space arranged side by side, and the motor of the embodiment is an example of an object to which the seal structure is applied. The seal structure includes a first member that partitions the first space, a second member that partitions the second space, and a partition member that separates the first space from the second space. The seal structure further includes a first packing portion that seals the first space between the first member and the partition member, and a second packing portion that seals the second space between the second member and the partition member. The first packing portion and the second packing portion are integrally formed as a single packing (sealing member) and are attached to the partition member.

[0013] [1. Configuration] 1 is an axial cross-sectional view showing a motor 1 to which a seal structure according to this embodiment is applied, together with essential parts of a driven device driven by the motor 1. The motor 1 is, for example, an inner rotor type brushless motor, and includes a cylindrical stator 2, a rotor 3 disposed inside the stator 2, and a shaft 4 that rotates integrally with the rotor 3. The motor 1 also includes a cylindrical housing 10 with a bottom that houses the stator 2 and rotor 3, and an end bell 20 that closes the opening of the housing 10.

[0014] In this embodiment, the housing 10 opens on one side (left side in FIG. 1) in the direction in which the axis C of the shaft 4 extends (hereinafter referred to as the "axial direction"). The end bells 20 are provided on one side of the housing 10 in the axial direction and close the opening of the housing 10 from that side. The housing 10 defines a first space S1, which houses the stator 2 and the rotor 3, on the other side of the end bells 20 in the axial direction (right side in FIG. 1).

[0015] A driven device is disposed on one axial side of end bell 20. In other words, the driven device is disposed axially parallel to motor 1, or disposed on the opening side of housing 10 of motor 1. The driven device is, for example, a power window device that uses motor 1 as a drive source, and is mounted on a vehicle. The driven device includes an actuator (not shown) that is actuated by the rotational driving force of shaft 4, and also includes housing 30 that defines second space S2 that houses the actuator. The second space S2 is disposed axially parallel to first space S1, with end bell 20 sandwiched between them.

[0016] 1 shows only the fixed surface portion 31 of the housing 30 of the driven device, which is disposed axially opposite the end bell 20 when the driven device and the motor 1 are assembled. In other words, although portions of the housing 30 other than the fixed surface portion 31 are not shown in FIG. 1, the housing 30 defines the second space S2 by the fixed surface portion 31 and portions not shown.

[0017] The seal structure according to this embodiment is applied to motor 1 as a structure that seals both first space S1 and second space S2 that are arranged side by side in the axial direction. Housing 10 corresponds to the above-mentioned first member, and casing 30 corresponds to the above-mentioned second member. End bell 20 corresponds to the above-mentioned partition member, and separates first space S1 from second space S2.

[0018] The seal structure includes a first packing portion 41 that seals the first space S1 between the housing 10 and the end bell 20, and a second packing portion 42 that seals the second space S2 between the casing 30 and the end bell 20, with these packing portions 41, 42 being integrally formed as a single packing 40 that is attached to the end bell 20. This seal structure prevents the intrusion of foreign matter and moisture into the first space S1 and the second space S2 from the external space Sx outside the first space S1 and the second space S2. Note that in Figure 1, the cross section of the packing 40 is shown painted black for convenience.

[0019] Hereinafter, of the axial directions of the shaft 4, the other one mentioned above will be referred to as a first axial direction C1, and the other one mentioned above will be referred to as a second axial direction C2. Furthermore, directions perpendicular to the axial direction and away from and toward the axis C will be referred to as radial directions. Among the radial directions, the direction away from the axis C will be referred to as the radially outward direction, and the direction toward the axis C will be referred to as the radially inward direction. A direction perpendicular to the axial direction and going around the axis C will be referred to as the circumferential direction. Furthermore, in the following description, unless otherwise specified, it is assumed that the driven device and the motor 1 are assembled.

[0020] In the first space S1, the stator 2 is disposed so that its axis coincides with the axis C of the shaft 4, and is fixed to the housing 10. The rotor 3 is fixed to the shaft 4 with its axis coincident with the axis C of the shaft 4, and is disposed radially inside the stator 2 so as to face the stator 2 in the radial direction. As shown in the figure, bus bars 5, 6 may be provided on the first axial direction C1 side and the second axial direction C2 side of the stator 2, respectively.

[0021] Both busbars 5 and 6 are conductive components that connect multiple coils (not shown) provided in stator 2, and are, for example, thin, annular in shape with inner and outer diameters substantially equal to those of stator 2. A connector 7 may protrude in the second axial direction C2 from an end face of busbar 6 provided on the second axial direction C2 side of stator 2 that faces the second axial direction C2. The connector 7 is connected to a power supply device (not shown) provided outside motor 1 (for example, in second space S2). For example, connector 7 axially penetrates both end bell 20 and fixed surface portion 31 and extends into second space S2.

[0022] Motor 1 includes two bearings 8, 9 that support shaft 4, which is fixed to the radially inner side of rotor 3. Shaft 4 is supported by these two bearings 8, 9 so as to be rotatable (freely rotatable) relative to housing 10 and end bell 20. One bearing 8 is housed, for example, in a first housing portion 14 of housing 10, which will be described later, and supports the end of shaft 4 on the first axial direction C1 side. The other bearing 9 is housed, for example, in a second housing portion 24 of end bell 20, which will be described later, and supports the portion of shaft 4 on the second axial direction C2 side.

[0023] The portion of the shaft 4 on the first axial direction C1 side is accommodated in the first space S1, and the portion on the second axial direction C2 side extends into the second space S2, axially penetrating both the second accommodating portion 24 and the fixed surface portion 31. However, when a shaft member (not shown) of an actuator of the driven device is connected to the shaft 4 within the first space S1, the shaft 4 may be entirely accommodated in the first space S1 without penetrating the end bell 20 (second accommodating portion 24).

[0024] The housing 10, which serves as a first member, defines a first space S1 on the first axial direction C1 side of the end bell 20. In this embodiment, the housing 10 is cylindrical with a bottom that opens in the second axial direction C2, and has a bottom portion 11 and a tubular portion 12. The bottom portion 11 extends in a direction perpendicular to the axial direction, centered on the axis C, on the first axial direction C1 side of the housing 10. The tubular portion 12 extends from the outer peripheral edge of the bottom portion 11 in the second axial direction C2 and forms a tubular shape that surrounds the axis C.

[0025] The housing 10 of this embodiment further has a flange 13 extending radially outward from the end of the cylindrical portion 12 on the second axial direction C2 side. Here, FIG. 2 is a perspective view of the motor 1 as viewed from the first axial direction C1 side, and FIG. 3 is a perspective view of the end bell 20 and the packing 40 as viewed from the first axial direction C1 side. Also, FIG. 4 is a plan view of the motor 1 as viewed from the second axial direction C2 side. As shown in FIG. 2, the flange 13 extends radially outward from the entire circumference of the end of the cylindrical portion 12 on the second axial direction C2 side, forming an annular shape surrounding the axis C. As shown in FIG. 1, these portions 11 to 13 form a hat-shaped axial cross section of the housing 10.

[0026] 2, the housing 10 is cylindrical with a bottom, having an annular bottom portion 11 and flange portion 13 centered on the axis C, and a cylindrical tubular portion 12. A first accommodating portion 14 for accommodating the bearing 8 may be provided at a radially inner portion of the bottom portion 11 so as to be convex toward the first axial direction C1 (so that the bottom portion 11 is recessed). The housing 10 is made of metal, for example, and the above-mentioned portions 11 to 14 are integrally formed.

[0027] 1, end bell 20 as a partition member is disposed (interposed) between housing 10 and casing 30, and closes the opening of housing 10. End bell 20 is deployed around axis C in directions (i.e., radial and circumferential directions) perpendicular to the axial direction in which first space S1 and second space S2 are arranged side by side, and is disposed opposite fixed surface portion 31 in the axial direction.

[0028] In this embodiment, end bell 20 has a main surface portion 21, a flange portion 22, a standing edge portion 23, and a second housing portion 24 (housing portion). When viewed from the first axial direction C1 side, end bell 20 is formed to have a shape and size that encompasses housing 10, as shown in Fig. 2. End bell 20 is made of, for example, metal, and these portions 21 to 24 are formed integrally.

[0029] The main surface portion 21 is a portion that covers the flange portion 13 of the housing 10 from the second axial direction C2 side, and has an annular shape that surrounds the axis C as shown in Fig. 3. The main surface portion 21 may be annular and centered on the axis C, corresponding to the shape of the flange portion 13. The main surface portion 21 is set so that at least its inner diameter is smaller than the inner diameter of the flange portion 13, and its outer diameter is set to be equal to or slightly larger than the outer diameter of the flange portion 13, and covers the entire circumferential area of ​​the flange portion 13 from the second axial direction C2 side.

[0030] 1, the main surface portion 21 of this embodiment extends radially outward from the second accommodating portion 24 between the flange portion 13 and the fixed surface portion 31, and also serves as a partition wall that separates the first space S1 and the second space S2 together with the second accommodating portion 24. The main surface portion 21 is flat and has a first side surface 21f facing the first axial direction C1 and a second side surface 21g facing the second axial direction C2.

[0031] A radially outer portion of the first side surface 21f faces an end surface 13f of the flange portion 13 of the housing 10, the end surface 13f facing the second axial direction C2. The second side surface 21g faces an outer surface 31g of the fixed surface portion 31, the outer surface 31g facing the first axial direction C1. In a facing region R where the first side surface 21f and the end surface 13f face each other, a first packing portion 41 is interposed between the main surface portion 21 and the flange portion 13. In a region where the second side surface 21g and the outer surface 31g face each other, a second packing portion 42 is interposed between the main surface portion 21 and the fixed surface portion 31. For convenience, in FIGS. 3 and 4, the packing 40 is indicated by light dots. For ease of understanding, in FIG. 3, the region where the end surface 13f faces the first side surface 21f is indicated by dark dots as the facing region R.

[0032] A connector hole 21h, through which the connector 7 is inserted, may be drilled in the axial direction in a position radially inwardly shifted from the opposing region R in the main surface portion 21. As shown in Fig. 4, the connector hole 21h may have a shape that is slightly larger in the radial direction than the radial length of the connector 7 and wider in the circumferential direction than the circumferential length of the connector 7. This allows motors 1 having different circumferential positions of the connector 7 relative to the flange portion 22, which is the fixing point with the driven device, to be constructed using a common end bell 20, which contributes to standardization of motor 1 components.

[0033] The flange portion 22 is a portion that extends radially outward from a portion of the outer circumferential edge of the main surface portion 21, and is disposed axially opposite the fixed surface portion 31. In this embodiment, the motor 1 and the driven device are assembled by fixing this flange portion 22 to the fixed surface portion 31. The end bell 20 may be provided with a plurality of flange portions 22. In this embodiment, the end bell 20 is provided with three flange portions 22. All three flange portions 22 have the same shape, are spaced apart from each other in the circumferential direction, and are arranged to be three-way rotationally symmetric about the axis C.

[0034] The flange portion 22 has, for example, an arched shape protruding radially outward from a portion of the outer circumferential edge of the main surface portion 21 when viewed in the axial direction, and as shown in Fig. 1 , has a generally flat plate shape with a surface facing the first axial direction C1 and a surface facing the second axial direction C2 when viewed in the radial direction. Fastening holes 22h are drilled in the axial direction in the flange portion 22 for inserting fastening members (not shown) that fasten the flange portion 22 to the fixed surface portion 31. Note that the annular portion of the flange portion 22 that forms the fastening holes 22h may be slightly shifted toward the second axial direction C2 from the portion excluding the annular portion, as shown in Figs. 1 and 3 .

[0035] The standing edge portion 23 is a portion that rises (stands up) toward the first axial direction C1 from a portion (other portion) of the outer peripheral edge of the main surface portion 21 excluding the outer peripheral edge to which the flange portion 22 extends. As shown in Fig. 2, the standing edge portion 23 forms a curved wall surface that extends circumferentially and axially, and surrounds the flange portion 13 of the housing 10 located radially inward from the radially outer side. Note that, as shown in Figs. 2 and 3, the standing edge portion 23 may also rise toward the first axial direction C1 from a part of the edge of the flange portion 22 (for example, a portion excluding the vicinity of the peak of the arched shape) in addition to the outer peripheral edge (other portion) of the main surface portion 21.

[0036] As shown in Fig. 3, the provision of the above-described standing edge portion 23 gives end bell 20 a shallow dish-like shape with a depth in the axial direction. In other words, standing edge portion 23 makes the axial dimension of end bell 20 larger than the axial thickness of main surface portion 21. This increases the rigidity of end bell 20. Therefore, deformation of end bell 20, which is fixed to fixed surface portion 31, due to vibration from the driven device side is suppressed.

[0037] 2, the housing 10 is fixed to the end bell 20 by cutting and crimping the upright edge 23 toward the flange 13. In other words, the motor 1 is integrated with the end bell 20 by fixing the housing 10 to the end bell 20 by cutting and crimping, and the motor 1 is assembled to the driven device by fixing the flange 22 of the end bell 20 to the fixed surface 31.

[0038] In this way, housing 10 is fixed via end bell 20 rather than directly to fixed surface portion 31, thereby suppressing deformation of housing 10 caused by vibrations from the driven device side. Furthermore, housing 10, which is the side fixed by cutting and crimping, is not provided with holes or flanges related to fixing to end bell 20, so the concentration of stress generated in housing 10 is alleviated.

[0039] In addition, because flange 13 of housing 10, which is fixed by cutting and crimping at upstanding edge 23, is annular, its circumferential position relative to end bell 20 can be freely changed (rotated) before being fixed to end bell 20. This means that there is no need to redesign housing 10 or components 2 to 9 housed therein, and the relative circumferential position of the above components (e.g., connector 7) with respect to flange 22 of end bell 20 can be freely set to match the specifications of the driven device. This contributes to the standardization of motor 1 components.

[0040] As shown in the figure, the flange 13 of the housing 10 is preferably cut and crimped intermittently at multiple locations in the circumferential direction by the standing edges 23. This distributes the stress acting on the flange 13, thereby mitigating the concentration of stress occurring in the housing 10. The amount by which the standing edges 23 rise relative to the main surface 21 is set to be greater than the axial thickness of the flange 13.

[0041] As shown in FIG. 1, the second accommodating portion 24 is formed in a radially inner portion of the end bell 20 and is a portion that accommodates the bearing 9. In this embodiment, as shown in FIG. 3, the second accommodating portion 24 is a cylindrical portion with a bottom, in which the radially inner portion of the main surface portion 21 is convex toward the second axial direction C2 (so that the main surface portion 21 is concave). A shaft hole 24h for inserting the shaft 4 is drilled in the axial direction at the bottom of the second accommodating portion 24. As shown in FIG. 1, the second accommodating portion 24 may be provided so as to axially penetrate the fixed surface portion 31 together with the shaft 4. However, the second accommodating portion 24 only needs to be configured to be able to accommodate the bearing 9 in the radially inner portion of the end bell 20, and does not have to be recessed in the main surface portion 21. In this case, the second accommodating portion 24 does not have to axially penetrate the fixed surface portion 31.

[0042] The fixed surface portion 31 of the housing 30 serving as the second member is a surface portion having an outer surface 31g that faces the end bell 20 in the axial direction and extends in a direction perpendicular to the axial direction. As shown in the figure, holes may be drilled in the axial direction in the fixed surface portion 31 for inserting the shaft 4, the second accommodating portion 24, the connector 7, and fastening members to be inserted into the flange portion 22. Note that instead of drilling holes in the fixed surface portion 31 for inserting the fastening members, fastening members (for example, stud bolts) may be provided to protrude from the outer surface 31g.

[0043] Finally, the packing 40 will be described with reference to Figures 5 to 7. Figures 5 and 6 are partial axial cross-sectional views of the end bell 20 and the packing 40 (views corresponding to the cross-sectional views taken along the arrows XX and YY in Figure 4, respectively), and Figure 7 is a perspective view of the packing 40 as viewed from the first axial direction C1 side.

[0044] As described above, the first packing portion 41 seals the first space S1 between the housing 10 and the end bell 20. As shown in FIG. 3, the first packing portion 41 has an annular shape surrounding the axis C in the facing region R that is radially outward of the connector hole 21h in the main surface portion 21 of the end bell 20. As a result, the first packing portion 41 is compressively deformed between the main surface portion 21 and the flange portion 13 over the entire circumferential direction, as shown in FIG. 1, and is pressed against both the first side surface 21f and the end face 13f. This seals the first space S1, preventing the intrusion of foreign matter and moisture from the external space Sx into the first space S1.

[0045] The first packing portion 41 may be, for example, annular in shape about the axis C, as shown in Fig. 3. Furthermore, the axial cross-sectional shape of the first packing portion 41 may be semicircular, bulging out from the first side surface 21f toward the first axial direction C1, in an unfixed state in which the housing 10 and the end bell 20 are not fixed to each other, as shown in Fig. 5. Hereinafter, the radial center position of the first packing portion 41 (i.e., the position of the apex of the semicircle) will be referred to as the first position P1.

[0046] As described above, second packing portion 42 seals second space S2 between end bell 20 and housing 30. As shown in FIG. 4, second packing portion 42 has an annular shape that surrounds axis C, radially outward of connector hole 21h in main surface portion 21 of end bell 20. As a result, second packing portion 42 is compressively deformed between main surface portion 21 and fixed surface portion 31 over the entire circumferential direction, as shown in FIG. 1, and is pressed against both second side surface 21g and outer surface 31g. This seals second space S2, preventing the intrusion of foreign matter and moisture from external space Sx into second space S2.

[0047] The second packing portion 42 may have an annular shape centered on the axis C, as shown in FIG. 4 . Furthermore, as shown in FIG. 6 , the second packing portion 42 may have an axial cross-sectional shape that is an epicentric semicircular arch (a shape that combines a rectangle and a semicircle) that bulges from the second side surface 21g toward the second axial direction C2 in an unassembled state in which the end bell 20 and the fixed surface portion 31 are not assembled. However, if the packing 40 does not have a protruding edge portion 44 or a connecting portion 46 (described later), the second packing portion 42 may have a semicircular cross-sectional shape similar to the first packing portion 41. Hereinafter, the radial center position of the second packing portion 42 (i.e., the position of the apex of the semicircle of the epicentric semicircular arch) will be referred to as the second position P2.

[0048] In this seal structure, as described above, the first packing portion 41 and the second packing portion 42 are integrally formed as one packing 40. In other words, the packing portions 41, 42 that seal the two spaces S1, S2 arranged side by side in the axial direction are not formed as separate parts (members), but are integrally formed to constitute one packing 40.

[0049] This achieves sealing of both spaces S1, S2 (waterproofing on both sides) while minimizing an increase in the number of parts required to seal both spaces S1, S2 arranged side by side in the axial direction. At the same time, integrating first packing portion 41 and second packing portion 42 contributes to reducing the number of steps required for fixing end bell 20 to housing 10 and for assembling driven equipment to motor 1.

[0050] Furthermore, packing 40 having first packing portion 41 and second packing portion 42 is attached to end bell 20 in an unassembled and unfixed state, as shown in Fig. 3. This allows end bell 20 and packing 40 to be handled as a single component, which contributes to reducing the number of steps required for the above-mentioned fixing and assembling work and to preventing the work from becoming complicated.

[0051] 7, in addition to first packing portion 41 and second packing portion 42, packing 40 has linking portion 43, protruding edge portion 44, anchor portion 45, and connecting portion 46. Packing 40 is attached to end bell 20 by forming these portions 41 to 46 integrally with end bell 20 by outsert molding. Packing 40 is made of, for example, resin or rubber.

[0052] As described above, the first packing portion 41 and the second packing portion 42 form an annular shape surrounding the same axis C, and therefore the packing 40 having these portions 41, 42 also forms an annular shape surrounding the axis C as a whole. In this embodiment, the packing 40 forms an annular shape centered on the axis C as a whole, corresponding to the shapes of the first packing portion 41 and the second packing portion 42 described above.

[0053] 6, the connecting portion 43 is a portion that connects the first packing portion 41 and the second packing portion 42 in the axial direction, and is provided to penetrate the main surface portion 21 of the end bell 20. In this way, by connecting the first packing portion 41 and the second packing portion 42 by the connecting portion 43 that penetrates the end bell 20, the integration of the first packing portion 41 and the second packing portion 42 and the attachment of the packing 40 to the end bell 20 are simultaneously achieved.

[0054] When the first packing portion 41 and the second packing portion 42 are connected by the connecting portion 43, the first packing portion 41 and the second packing portion 42 are preferably provided so as to be shifted from each other in the radial direction. In other words, the first packing portion 41, the connecting portion 43, and the second packing portion 42 are preferably not provided axially in this order at the same radial position. In this embodiment, the second position P2, which is the radial position of the second packing portion 42, is provided so as to be shifted radially inward relative to the first position P1, which is the radial position of the first packing portion 41.

[0055] Here, it is generally known that the resin or rubber forming the packing 40 can pack (seal) in an elastic deformation region without plastic deformation when the ratio of the amount of compression to the length (here, the axial length) when no external force is applied is within a predetermined range (for example, 50 to 70%). Therefore, when the first packing portion 41, the connecting portion 43, and the second packing portion 42 are axially connected at the same radial position, a difference occurs between the ratio of the amount of compression of the packing 40 near the connecting portion 43 and the ratio of the amount of compression of the first packing portion 41 and the second packing portion 42 at other locations, which may make it difficult to uniformly seal each of the first space S1 and the second space S2 in the circumferential direction.

[0056] In contrast, in the present embodiment, the first position P1 of the first packing portion 41 and the second position P2 of the second packing portion 42 are radially offset from each other. This reduces the difference in the rate of squeezing of the packing portions 41, 42 between the vicinity of the connecting portion 43 and other portions. This allows the first space S1 and the second space S2 to be more appropriately sealed.

[0057] The packing 40 may be provided with a plurality of connecting portions 43. As shown in Fig. 7, the packing 40 of this embodiment is provided with six connecting portions 43. All six connecting portions 43 may have the same shape and be provided at equal intervals spaced apart from one another in the circumferential direction. For example, as shown in Fig. 6, each connecting portion 43 is provided adjacent to the first packing portion 41 on the second axial direction C2 side, and is connected to the protruding edge portion 44 and a radially outer portion of the second packing portion 42.

[0058] 4 and 6, first through holes 21i for forming connecting portions 43 are drilled in the axial direction in main surface portion 21 of end bell 20. In correspondence with the number and arrangement of the above-mentioned connecting portions 43, six first through holes 21i may be drilled in main surface portion 21 at radial positions that overlap with first packing portion 41 in the axial direction and are equally spaced apart in the circumferential direction.

[0059] The protruding edge portion 44 is a portion that protrudes radially outward from the second packing portion 42 on the second axial direction C2 side of the end bell 20 and connects the second packing portion 42 and the connecting portion 43. The protruding edge portion 44 may be, for example, an annular portion that extends radially outward from the second packing portion 42 over the entire circumferential area. However, because the protruding edge portion 44 is a portion that connects the second packing portion 42 and the connecting portion 43, it may be provided only around the connecting portion 43. The axial length of the protruding edge portion 44 is set to be at least shorter than the axial length of the second packing portion 42 in the unassembled state, as shown in FIG. 5 .

[0060] Anchor portion 45 is a portion that acts as an anchor that engages with end bell 20, and is provided to penetrate main surface portion 21 of end bell 20. As shown in Fig. 7, anchor portion 45 has a stepped cylindrical shape in which the diameter of the portion on the first axial direction C1 side is larger than the diameter of the portion on the second axial direction C2 side.

[0061] 5, the anchor portion 45 is preferably provided at a position radially shifted from both the first position P1 of the first packing portion 41 and the second position P2 of the second packing portion 42. Hereinafter, the radial center position of the anchor portion 45 will be referred to as the anchor position Pa. As shown in the figure, the anchor portion 45 of this embodiment is provided radially inward of the second packing portion 42 and is connected to the second packing portion 42 (one of the first packing portion 41 and the second packing portion 42) via a connecting portion 46. In other words, the anchor position Pa is set radially inward of the first position P1 and the second position P2.

[0062] The packing 40 may be provided with a plurality of anchor portions 45. As shown in Fig. 7, the packing 40 of this embodiment is provided with three anchor portions 45. All three anchor portions 45 have the same shape and are provided at equal intervals in the circumferential direction. For example, the three anchor portions 45 may be provided so that every two of the six connecting portions 43 are spaced apart.

[0063] 4 and 5, second through holes 21j for forming anchor portions 45 are drilled in the axial direction in the main surface portion 21 of the end bell 20. Three second through holes 21j are drilled in the main surface portion 21 at equal intervals in the circumferential direction, corresponding to the number and arrangement of the anchor portions 45. As shown in FIG. 5, each second through hole 21j has a stepped shape in which the hole diameter on the first axial direction C1 side is larger than the hole diameter on the second axial direction C2 side, corresponding to the shape of the anchor portions 45.

[0064] Because second through hole 21j is a hole for forming anchor portion 45, the anchor position Pa described above can also be said to be the radial position of second through hole 21j. By providing anchor portion 45 in second through hole 21j, a portion of anchor portion 45 on the first axial direction C1 side engages with a portion of second through hole 21j on the first axial direction C1 side. This prevents packing 40 from coming off end bell 20. In this embodiment, second through hole 21j serves as a gate during outsert molding.

[0065] The connecting portion 46 is a portion that connects the second packing portion 42 and the anchor portion 45 on the second axial direction C2 side of the end bell 20. For example, as shown in FIG. 7 , the connecting portion 46 may be extended in a direction perpendicular to the axial direction about the anchor portion 45 on the second axial direction C2 side of the anchor portion 45, and may be connected to a part of the radially inner edge portion of the second packing portion 42. However, because the connecting portion 46 is a portion that connects the second packing portion 42 and the anchor portion 45, it may be provided so as to extend radially inward from the entire radially inner edge portion of the second packing portion 42, similar to the overhanging edge portion 44. The axial length of the connecting portion 46 is set to be shorter than at least the axial length of the second packing portion 42 in an unassembled state, as shown in FIG. 5 .

[0066] During outsert molding, rubber or resin (hereinafter referred to as "molten material") supplied to second through hole 21j serving as a gate flows through second through hole 21j toward second axial direction C2 as shown by arrow A1 in FIG. 5. The molten material then flows radially outward as shown by arrows A2 and A3 in FIG. 5 into the space formed between end bell 20 and a cavity (not shown) provided on the second axial direction C2 side, filling the space to form second packing portion 42 and protruding edge portion 44. Furthermore, the molten material that has flowed radially outward within the space flows through first through hole 21i toward first axial direction C1 as shown by arrow A4 in FIG. 6, filling the space formed between end bell 20 and a cavity (not shown) provided on the first axial direction C1 side, filling the space to form first packing portion 41. This results in end bell 20 and portions 41-46 constituting packing 40 being integrally formed.

[0067] Here, in the region immediately downstream of the gate (second through hole 21j) in the flow direction of the molten material (i.e., the region indicated by arrow A1 in FIG. 5), the molten material is likely to expand or be depressed due to thermal contraction. In this embodiment, both the first packing portion 41 and the second packing portion 42 are formed at positions radially offset from the second through hole 21j. That is, since both the first packing portion 41 and the second packing portion 42 are formed in regions offset from the above-mentioned regions, the molding accuracy of the first packing portion 41 and the second packing portion 42 is improved. As a result, both the first space S1 and the second space S2 are more appropriately sealed by the first packing portion 41 and the second packing portion 42. In other words, in this embodiment, the connection portion 46, which does not contribute to sealing both the first space S1 and the second space S2, is formed in the above-mentioned region, thereby improving the sealing accuracy of the seal structure.

[0068] [2. Actions and Effects] (1) In the above-described seal structure, the first packing portion 41 that seals the first space S1 and the packing portion 42 that seals the second space S2 are integrally formed as a single packing 40 and attached to the end bell 20. This makes it possible to seal both spaces S1 and S2 arranged side by side in the axial direction while minimizing an increase in the number of parts required for sealing both spaces. Furthermore, because the end bell 20 and the packing 40 attached thereto can be treated as a single component, it is possible to reduce the number of steps required for fixing the end bell 20 to the housing 10 and for assembling the driven device and the motor 1, and to prevent these steps from becoming too complicated.

[0069] (2) In the above-described seal structure, packing 40 is formed integrally with end bell 20 by outsert molding. This allows the integrally formed first packing portion 41 and second packing portion 42 to be easily formed by outsert molding, thereby reducing manufacturing costs. Furthermore, the integration of first packing portion 41 and second packing portion 42 and the attachment of packing 40 to end bell 20 can be achieved simultaneously, which contributes to a reduction in manufacturing man-hours.

[0070] (3) When first packing portion 41 and second packing portion 42 are connected by connecting portion 43 that penetrates first through hole 21i of end bell 20, connecting portion 43 can prevent misalignment of the mounting positions of first packing portion 41 and second packing portion 42 relative to end bell 20. This contributes to more stable sealing of first space S1 and second space S2.

[0071] Furthermore, during outsert molding, the first through-holes 21i can be used as holes for flowing the molten material from the first axial direction C1 side to the second axial direction C2 side or vice versa, and the first packing portion 41 and the second packing portion 42 can be formed at the same time. This improves the ease of molding the first packing portion 41 and the second packing portion 42.

[0072] (4) When the first packing portion 41 and the second packing portion 42 are connected by the connecting portion 43, if the first packing portion 41 and the second packing portion 42 are provided so as to be shifted from each other in the radial direction, it is possible to reduce variations in the rate of the crushing amount in the circumferential direction of the first packing portion 41 and the second packing portion 42. This in turn contributes to more stable sealing of the first space S1 and the second space S2.

[0073] (5) When the packing 40 is provided with anchor portions 45 that engage with the second through holes 21j drilled in the end bell 20, the anchor portions 45 can prevent the first packing portion 41 and the second packing portion 42 from shifting in their mounting positions relative to the end bell 20. Furthermore, when the first packing portion 41 and the second packing portion 42 are both provided in positions that are radially shifted from the second through holes 21j that serve as gates during outsert molding, the molding precision of both the first packing portion 41 and the second packing portion 42 can be improved. This in turn contributes to more stable sealing of the first space S1 and the second space S2.

[0074] (6) In the motor 1 described above, the end bell 20 having the second housing portion 24 is used as the partition member of the sealing structure described above. In this way, by giving the end bell 20, which has the function of holding the bearing 9, the function of sealing both the first space S1 and the second space S2, it is possible to reduce the number of parts and improve the ease of handling of the parts. Furthermore, the first packing portion 41 and the second packing portion 42 prevent foreign matter from entering the space inside and outside the motor 1 around the bearing 9 from the external space Sx, thereby suppressing deterioration of the bearing 9 due to the foreign matter.

[0075] (7) In the motor 1 described above, the end bell 20 has a main surface portion 21, a flange portion 22, and a vertical edge portion 23. The motor 1 is assembled to the driven device via the flange portion 22 of the end bell 20, and the housing 10 is fixed to the end bell 20 by cutting and crimping. This increases the rigidity of the end bell 20 and reduces the concentration of stress that occurs in the housing 10. Furthermore, the housing 10, which is fixed to the end bell 20 by cutting and crimping, and the components 2 to 9 housed therein can be standardized.

[0076] [3. Other] The above-described seal structure and the configuration of the motor 1 are merely examples, and are not limited to the above-described configuration. The motor 1 to which the above-described seal structure is applied does not have to be an inner rotor brushless motor, but may be an outer rotor brushless motor. The motor 1 may also be a brushed motor. Note that the device (target object) to which the seal structure is applied does not have to be a motor.

[0077] The housing 10 does not have to be fixed to the end bells 20 by cutting and crimping. Also, the motor 1 may be assembled to the driven device by fixing the housing 10 to the fixed surface portion 31. In this case, the flange portion 22 and the standing edge portion 23 of the end bells 20 may be omitted. Also, in this case, the flange portion 13 of the housing 10 may also be omitted. The shapes of the housing 10 and the end bells 20 are merely examples and are not limited to the shapes described above.

[0078] It is sufficient that the first packing portion 41 and the second packing portion 42 are integrated as at least one packing 40 and attached to the end bell 20, and the connecting portion 43, the protruding edge portion 44, the anchor portion 45, and the connecting portion 46 of the packing 40 can be omitted. The first packing portion 41 and the second packing portion 42 may be integrated by being connected, for example, on the radially inner side or the radially outer side of the end bell 20. The packing 40 does not have to be formed by outsert molding. [Explanation of symbols]

[0079] 1 motor 2 stator 3 rotors 4 shafts 9 Bearings 10. Housing 13 Tsuba 20 End Bell 21 Main surface section 21i First through hole 21j Second through hole 22 Flange 23 Standing edge 24 Second storage section (storage section) 30 Case 40 Gasket 41 First packing part 42 Second packing part 43 Connecting part 45 Anchor part 46 Connection C axis C1 First axis direction C2 Second axis direction P1 First position (radial position of the first packing part) P2 Second position (radial position of second packing part) Pa Anchor position (radial position of the second through hole) S1 first space S2 Second space

Claims

1. a partition wall member separating the first space and the second space arranged side by side; a first member that defines the first space; a second member that defines the second space; a first packing portion that seals the first space between the first member and the partition member; a second packing portion that seals the second space between the second member and the partition member, the first packing portion and the second packing portion are integrally formed as one packing and are attached to the partition member, the packing is formed integrally with the partition member by outsert molding, and has an annular shape surrounding an axis extending in a direction in which the first space and the second space are arranged side by side; The partition member is provided with a second through hole drilled in the juxtaposition direction at a radial position shifted from a radial position centered on the axis of each of the first packing portion and the second packing portion, The packing is provided with an anchor portion that engages with the second through hole, and a connecting portion that connects the anchor portion to one of the first packing portion and the second packing portion in the radial direction. A seal structure characterized by:

2. The partition member is provided with a first through hole drilled in the juxtaposition direction, The first packing portion and the second packing portion are connected by a connecting portion that penetrates the first through hole. The seal structure according to claim 1 .

3. The first packing portion and the second packing portion are provided so as to be offset from each other in the radial direction. The seal structure according to claim 2 .

4. a cylindrical housing with a bottom; a rotor and a stator housed in the housing; a shaft that rotates integrally with the rotor; a bearing that rotatably supports the shaft; an end bell that closes the opening of the housing and is disposed opposite a housing of a driven device that is disposed on the opening side of the housing, the end bell has a housing portion that houses the bearing on a radially inner side centered on the axis of the shaft, The seal structure according to any one of claims 1 to 3 is applied to the end bell as the partition member, the housing as the first member, and the casing as the second member. A motor characterized by:

5. the housing has an annular flange portion extending radially outward on the opening side, the end bell has an annular main surface portion that covers the flange portion from the opening side, a flange portion that extends radially outward from a portion of an outer circumferential edge of the main surface portion and is fixed to the housing, and a standing edge portion that rises from the remaining portion of the outer circumferential edge of the main surface portion excluding the portion toward the housing, The housing is fixed to the end bell by cutting and caulking the upright edge toward the flange.

5. The motor according to claim 4, wherein the motor comprises:

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