SHAFT BEARING SUPPORT STRUCTURE AND ENGINE

Abstract

A shaft bearing retaining structure (1), which holds a shaft bearing (2) on the tube section (4) via an O-ring (5) in contact with an inner surface (4f) of a plastic tube section (4), comprises a pair of groups (6G, 7G) of convex sections projecting radially inwards from the inner surface (4f) of the tube section (4) and arranged such that the O-ring (5) lies axially between them. Each group (6G, 7G) of convex sections has several convex sections (6, 7) extending circumferentially spaced apart from one another, wherein, in the case of the multiple convex sections (6, 7), convex sections (6, 7) adjacent to each other circumferentially have different circumferential lengths.

Description

Technical field

[0001] The present subject matter relates to a shaft bearing support structure, or in short, a bearing support structure for holding a shaft bearing or bearing, and to a motor to which it is applied. General state of the art

[0002] A structure is known from the prior art in which a shaft bearing is held by an O-ring inserted between a round-tube fixing section and a shaft bearing inserted radially on the inside of the fixing section. For example, patent document 1 discloses a structure in which the shaft bearing is fixed to an end plate of a motor by a sealing element (O-ring) provided between an inner surface of a round-tube receiving section and an outer surface of a shaft bearing. In patent document 1, several bead sections are provided on the receiving section, projecting from its inner surface.The O-ring is inserted into a space between several bead sections arranged in a first annular row and several bead sections arranged in a second annular row at a position axially removed from the first annular row. The multiple bead sections each have essentially the same shape and are arranged symmetrically. State-of-the-art documents, patent documents

[0003] Patent document 1: European patent publication no. 4186148 Brief description of the invention Task of the invention

[0004] A shaft bearing that rotatably supports a shaft is required to function in such a way that the shaft can rotate stably. However, it is possible for the shaft bearing to vibrate due to the shaft it supports. If, as in the shaft bearing support structure disclosed in Patent Document 1, the several ring-shaped bead sections have essentially the same shape, there is a possibility that resonance may occur with the shaft bearing due to resonant vibration of the several bead sections. In other words, the shaft bearing support structure disclosed in Patent Document 1 requires improvement with regard to suppressing vibrations (resonant vibrations) that accompany vibrations of the shaft bearing.

[0005] The shaft bearing support structure and the motor of the present invention are proposed in consideration of this problem, and their underlying objective is to suppress vibrations (resonance vibrations) associated with vibrations of the shaft bearing. The objective of the present invention is not limited to this, however, and further aims to achieve effects resulting from various embodiments of the invention described below, which cannot be achieved in the prior art. Means of solving the task

[0006] The shaft bearing support structure and the motor of the disclosure can be implemented in the aspects disclosed below (application examples) and fulfill at least part of the task stated above. Aspects 2 to 8 are optional and can be omitted as desired. Aspects 2 to 8 are not disclosed as aspects or configurations that are essential for the present subject matter.

[0007] Aspect 1. A shaft bearing retaining structure of the disclosure is a shaft bearing retaining structure comprising a plastic tube section and an O-ring arranged in contact with an inner surface of the tube section to retain a shaft bearing on the tube section via the O-ring. The structure comprises a pair of groups of convex or projecting sections that project radially inward from the inner surface of the tube section and are arranged such that the O-ring lies axially between them. Each group of convex sections has several convex sections that extend circumferentially spaced apart from one another. Among the multiple convex sections, circumferentially adjacent convex sections have different circumferential lengths.

[0008] Aspect 2. In an aspect that includes aspect 1 above, the multiple convex sections are preferably arranged asymmetrically such that they are not rotationally symmetric with respect to an axis of the pipe section and are not line-symmetric with respect to a diameter line that crosses the axis.

[0009] Aspect 3. In an aspect that includes aspect 2 above, the multiple convex sections, which are arranged asymmetrically, are preferably all of different perimeter lengths.

[0010] Aspect 4. In an aspect encompassing aspect 3 above, the pair of convex sections preferably comprises a first group of convex sections located at the front when viewed from the direction in which the shaft bearing is inserted into the tube section, and a second group of convex sections located at the rear when viewed from the insertion direction, wherein the second group of convex sections includes the convex sections that are arranged asymmetrically. In this case, the shaft bearing retaining structure preferably further comprises a confining section that connects the respective asymmetrically arranged convex sections and extends further radially inward with respect to the multiple second groups of convex sections to restrict rearward movement of the shaft bearing.

[0011] Aspect 5. In an aspect that includes aspect 4 above, at least one through hole extending axially is preferably arranged between convex sections adjacent in the circumferential direction.

[0012] Aspect 6. In an aspect that includes aspect 5 above, the multiple convex sections of the first group of convex sections, when viewed from the axial direction, are preferably arranged within areas of superposition with the at least one through-hole and are all of the same circumferential length.

[0013] Aspect 7. In an aspect that includes aspect 6 above, the multiple convex sections of the first group of convex sections are preferably arranged asymmetrically.

[0014] Aspect 8. In an aspect that includes aspect 1 above, the pipe section preferably has a flat section extending radially outwards from an outer surface of the pipe section, and several ribs projecting axially from the flat section and extending radially outwards from the outer surface of the pipe. In this case, the several ribs are preferably arranged at positions of the same phase as the several convex sections of one of the pair of groups of convex sections.

[0015] Aspect 9. A motor of the disclosure comprises an enclosure in the form of a tube with a bottom, an end bell closing an opening of the enclosure, a rotor and a stator housed in the enclosure, a shaft rotating integrally with the rotor, a shaft bearing rotatably supporting the shaft, a tube section arranged at at least one of the enclosure and the end bell into which the shaft bearing is inserted, and an O-ring inserted between an inner surface of the tube section and an outer circumferential surface of the shaft bearing, the shaft bearing being held by the shaft bearing retaining structure according to any of Aspects 1 to 8 above. Effect of the invention

[0016] According to the shaft bearing support structure and the motor of the disclosure, vibrations (resonance vibrations) associated with vibrations of the shaft bearing can be suppressed. Brief description of the characters Fig. Figure 1 is a sectional view in the axial direction of a motor to which the shaft bearing support structure of an embodiment is applied. Fig. 2 is an enlarged sectional view of part X from Fig. 1. Fig. Figure 3 is a top view of an end bell of the engine. Fig. 1 from a first direction. Fig. 4 is a section view at arrow AA from Fig. 3. Fig. 5 is a section view at arrow BB from Fig. 3. Fig. Figure 6 is a top view of the end bell of the engine. Fig. 1 from a second direction. Fig. Figure 7 is an enlarged view of section Y from Fig. 3. Embodiments of the invention

[0017] With reference to the figures, an embodiment of the shaft bearing support structure and the motor will now be described. The following embodiment is merely exemplary and is in no way intended to exclude the application of various modifications or techniques not presented in this embodiment. The individual configurations of the present embodiment allow for various modifications without deviating from its scope. Substitutions and omissions are also possible as needed, as are suitable combinations. In the following description, a direction in which an axis of a shaft rotatably supported by a shaft bearing extends is referred to as the "axial direction," a radial direction of the shaft around the axis is referred to simply as the "radial direction," and a direction around the axis is referred to as the "circumferential direction." [1. Overall structure]

[0018] Fig. Figure 1 is a sectional view in the axial direction of a motor 10 to which a shaft bearing support structure 1 (hereinafter referred to as "support structure 1") is applied according to the present embodiment. As in Fig. As shown in Figure 1, the motor 10 is a brushless internal rotor motor, designed by housing a rotor 20, which rotates integrally with a shaft 21, and a stator 30, which is located radially outside the rotor 20, within a housing 40. In the case of the motor 10, for example, a vane (not shown) is fixed to the shaft 21, so that it serves as a drive source for a blower.

[0019] The rotor 20 has a magnet 22 fixed to the shaft 21 and two compensators 23 that clamp the magnet 22 axially. It is rotatably mounted on the housing 40 and an end bell 50 by means of a shaft bearing 2. The stator 30 has a stator core 31 fixed to the inner circumferential surface of the housing 40 and a coil 33 wound onto the stator core 31 by means of an insulator 32.

[0020] The housing 40 is a plastic element that forms a space in which the rotor 20 and the stator 30 are accommodated. The housing 40 is in the form of a tube with a base, comprising a tubular side wall 41 that forms a receiving space for the rotor 20 and the stator 30, and a base section 42 that closes the side wall 41 from one side in the axial direction. On the radially inner side of the base section 42, a tube section 3 is arranged, into which the shaft bearing 2, which supports the shaft 21, is inserted. The tube section 3 is, for example, formed as a tube with a through hole extending axially through it. During assembly of the motor 10, the shaft bearing 2 is inserted into the tube section 3 from the opposite side in the axial direction towards one side.On the opening side of the housing 40 (the radially opposite side), an annular flange section 43 can be provided, extending radially outwards from the side wall 41. A flange section 52 of the end bell 50, described below, is placed on the flange section 43. On a surface of the flange section 43 facing the axially opposite side, recesses and protrusions are provided as shown.

[0021] The end cap 50 is a plastic cover element that closes the opening of the housing 40 and is attached to the housing 40. The end cap 50 has a radially extending surface section 51 and an annular flange section 52 that extends radially outwards from the surface section 51. The surface section 51 is the part that primarily closes the opening of the housing 40. A tube section 4, into which the shaft bearing 2 is inserted, is arranged on the radially inner side of the surface section 51. The tube section 4 is, for example, formed as a tube with a through hole extending axially through it. During assembly of the motor 10, the shaft bearing 2 is inserted into the tube section 4 from one side to the other. The flange section 52 rests on the flange section 43 of the housing 40.In this state, the end bell 50 is fixed to the housing 40. On a surface of the flange section 52 on one side in the axial direction, recesses and protrusions may be provided which are inserted into the recesses and protrusions of the flange section 43 of the housing 40.

[0022] The retaining structure 1 of the present embodiment holds the shaft bearing 2 and can be applied to the pipe section 3 of the housing 40 and the pipe section 4 of the end bell 50, respectively. The retaining structure 1 comprises the pipe sections 3, 4 and an O-ring 5 and is a structure that, via the O-ring 5 arranged on the radially inner side of the pipe sections 3, 4, holds the shaft bearing 2 on the radially inner side of the pipe sections 3, 4.

[0023] The shaft bearing 2 is a component that supports the shaft 21 on one side and forms a round tube with a central through-hole. The shaft bearing 2 is arranged coaxially with an axis C of the shaft 21. In the present embodiment, a ball bearing is shown as an example of the shaft bearing 2, but there is no restriction regarding the type of shaft bearing 2. In the present embodiment, a shaft bearing 2 with a uniform outer diameter in the axial direction is shown as an example, but the shaft bearing 2 need not have a uniform outer diameter in the axial direction.

[0024] The following description uses as an example the retaining structure 1 applied to pipe section 4 of the end bell 50. However, if the retaining structure 1 is applied to pipe section 3 of the housing 40, the design described below is also applicable to pipe section 3 of the housing 40. As discussed above, the shaft bearing 2 is inserted into the radial interior of pipe section 4 from one side in the axial direction towards the other. The following describes a direction that is forward when viewed from the direction in which the shaft bearing 2 is inserted into pipe section 4 (i.e., one axial direction). Fig. 1 below) is referred to as the “first direction”. A direction that lies behind when viewed from the direction in which the shaft bearing 2 is inserted into the pipe section 4 (here the other axial direction, in Fig. 1 above) is referred to as the “second direction”. The front side can also be described as the side on which, when the shaft bearing 2 is inserted into the pipe section 4, the shaft bearing 2 is arranged with respect to the pipe section 4, and the rear side can be described as the opposite side.

[0025] Fig. Figure 2 is an enlarged view of part X from Fig. 1, Fig. Figure 3 is a top view of the end bell 50 from the first direction (from the side of the housing 40) and Fig. 4 is a section view at arrow AA from Fig. 3. In Fig. Figure 2 shows the surface section 51 and the ribs 53 described below, the tube section 4, the second convex sections 7 described below, and a restriction section 8 described below, each with different hatching. However, these parts 4, 7, 8, 51, 53, and a first convex section 6 described below can be molded in one piece from plastic as the end bell 50. In other words, the end bell 50, as shown in Figure 2, has a surface section 51 and the ribs 53 described below. Fig. Figures 2 to 4 show the round tubular pipe section 4, which is arranged essentially coaxially to the axis C of the shaft 21, the surface section 51 projecting outwards in the radial direction from the pipe section 4 and the flange section 52, which is connected to the outer circumferential edge of the surface section 51.

[0026] An inner surface 4f of the round tube-shaped pipe section 4 is, as in Fig. 2 shown, arranged at a distance from an outer circumferential surface 2g of the shaft bearing 2 on the radially outer side opposite it. The inner pipe surface 4f of the present embodiment has a uniform diameter in the axial direction. An outer pipe surface 4g of the pipe section 4 can have a uniform diameter in the axial direction or, as shown in Fig. 2 and Fig. As shown in Figure 4, a part on the side of the first direction can become progressively smaller in diameter in the first direction.

[0027] Surface section 51 is a plate-shaped part that extends radially outwards from a section of the outer surface of the tube 4g. In the present embodiment, surface section 51 extends radially outwards from the part of the outer surface of the tube 4g on the side of the second direction and is defined by a shape and size that covers the entire opening of the housing 40. Viewed in the axial direction, surface section 51 forms a circular outer shape, as shown in Fig. Figure 3 shows that several through-holes for positioning the stator 30 can be provided on surface section 51. As shown in Fig. As shown in Figure 4, the flange section 52 is a part that initially extends to the outer circumferential edge of the surface section 51, then in a radial direction outwards and in the first direction, and then forms a surface section that can be placed on the flange section 43 of the housing 40.

[0028] Several ribs 53 can be provided at the end bell 50 to reinforce the end bell 50, as shown in Fig. 3 and Fig. Figure 4 shows that the ribs 53 project from the surface section 51 in the axial direction (direction orthogonal to the extension direction of the surface section 51) and extend radially outwards from the outer surface 4g of the pipe. In the present embodiment, the ribs 53 are provided projecting from the surface section 51 in the first direction and extend radially outwards from the portion of the outer surface 4g of the pipe on the side of the first direction. The end section of the ribs 53 on the radially outer side can be connected to the flange section 52. As shown in Fig. As shown in Figure 3, the ribs 53 are provided in the same number as the multiple second convex sections 7 of a second group 7G of convex sections described below and are arranged at positions of the same phase as the second convex sections 7. Thus, not only is the end bell 50 reinforced, but also the second convex sections 7. [2. Shaft bearing support structure]

[0029] With reference to Fig. Sections 2 to 7 below describe the design of the holding structure 1. Fig. 5 is a section view at arrow BB from Fig. 3 and Fig. Figure 6 is a top view of the end bell 50 from the second direction. Fig. Figure 7 is an enlarged view of section Y from Fig. 3.

[0030] As in Fig. As shown in Figure 2, the retaining structure 1 comprises, in addition to the tube section 4 and the O-ring 5, a pair of groups 6G, 7G of convex or projecting sections, respectively, arranged such that the O-ring 5 lies axially between them. The retaining structure 1 of the present embodiment also includes the restricting section 8 as part of limiting the movement of the shaft bearing 2.

[0031] The O-ring 5 is a circular sealing component made of an elastic material (for example, rubber) and is arranged in contact with the inner surface 4f of the pipe section 4. Before the shaft bearing 2 is inserted into the pipe section 4, the O-ring 5 is inserted from the first direction to the second direction, such that it lies between the pair of convex sections 6G, 7G. In a state where the shaft bearing 2 is held on the radially inner side of the pipe section 4 (hereinafter referred to as the "holding state"), the O-ring 5 is positioned between the inner surface 4f of the pipe section 4 and the outer circumferential surface 2g of the shaft bearing 2 and is pressed against both the inner surface 4f and the outer circumferential surface 2g.

[0032] The pair of convex sections 6G and 7G are each parts that project radially inwards from the inner surface 4f of the pipe section 4, wherein the convex section groups 6G and 7G each have several convex sections 6 and 7 that extend circumferentially spaced apart from one another. The multiple convex sections 6 and 7 are molded in one piece from plastic together with the pipe section 4.

[0033] In the present embodiment, the pair of groups 6G, 7G of convex sections comprises a first group of 6G convex sections, which in the holding state lies in the first direction with respect to the O-ring 5, and a second group of 7G convex sections, which in the holding state lies in the second direction with respect to the O-ring 5. As shown in Fig. As shown in Figure 3, the first group of 6G convex sections has several first convex sections 6, and the second group of 7G convex sections has several second convex sections 7. Fig. 2 to 6 is only one of the multiple provided first convex sections 6 with a reference symbol. Likewise, in Fig. 2 to 6 only one of the multiple provided second convex sections 7 is provided with reference numerals.

[0034] As in Fig. As shown in Figure 3, in the present embodiment, the groups 6G and 7G of convex sections each have the same number of convex sections 6 and 7. The multiple first convex sections 6 and the multiple second convex sections 7 are arranged alternately without overlapping each other in the circumferential direction. Thus, when viewed from the axial direction, for example, between two circumferentially adjacent convex sections 6 of the first group 6G of convex sections, there is a convex section 7 of the second group 7G of convex sections. An exemplary embodiment is shown in which the two groups 6G and 7G of convex sections each have six convex sections 6 and 7, and when viewed from the axial direction, another convex section 7 is provided without a circumferential gap between circumferentially adjacent convex sections 6 and 7.

[0035] It sometimes happens that the shaft bearing 2 vibrates in conjunction with the rotation of the shaft 21. If, as in the holding structure 1 of the present embodiment, the convex sections 6, 7 projecting from the pipe section 4 are provided multiple times as parts that restrict axial movement of the O-ring 5, there is a possibility that the convex sections 6, 7 will resonate (vibrate or enter resonance) with the vibration of the shaft bearing 2. In particular, if the convex sections 6, 7 are made of plastic, which is softer than metal, and are integrally formed with the pipe section 4 (the end bell 50), they resonate more readily with the shaft bearing 2, since the convex sections 6, 7 deform flexibly.

[0036] Therefore, in the present embodiment, the convex sections 6, 7 are provided on the support structure 1 in such a way that their resonance with the shaft bearing 2 is suppressed. In other words, the support structure 1 includes a resonance suppression structure provided on the convex sections 6, 7. In the present embodiment, two resonance suppression structures are described. The support structure 1 can include both resonance suppression structures or only one of them.

[0037] The first resonance suppression structure consists of different circumferential lengths (hereinafter referred to as "circumferential lengths") of the convex sections 6 and 7 in the two groups 6G and 7G. That is, the circumferential lengths of the multiple convex sections 6 provided in the first group 6G and the circumferential lengths of the multiple convex sections 7 provided in the second group 7G are different.

[0038] The second resonance suppression structure consists of providing the multiple convex sections 6, 7 of the groups 6G, 7G with unequal dimensions, such that the circumferential lengths of adjacent convex sections 6, 7 are different. More precisely, considering a single first convex section 6 of the first group 6G, the circumferential length of this first convex section 6 and the circumferential length of another first convex section 6 adjacent to it in the circumferential direction are defined differently. The same applies to the multiple second convex sections 7 that form the second group 7G.

[0039] It is sufficient if the multiple convex sections 6, 7 provided with unequal dimensions are at least one of the multiple convex sections 6, 7 from the two groups 6G, 7G of convex sections (i.e., the multiple first convex sections 6 or the multiple second convex sections 7), but they can also be the convex sections 6, 7 from both groups 6G, 7G of convex sections. In other words, for the support structure 1 for the second resonance suppression structure, it is sufficient if at least the convex sections 6, 7 from one of the two groups 6G, 7G of convex sections with unequal dimensions are provided.

[0040] Furthermore, in the present embodiment, the multiple convex sections 6, 7, which are provided with unequal dimensions, are arranged as a second resonance suppression structure in a non-object-like manner with respect to the axis C of the pipe section 4. Asymmetric here means that the multiple convex sections 6, 7 with unequal dimensions are arranged such that they are not rotationally symmetric about the axis C (have a shape such that they do not overlap each other even when rotated) and are not axially symmetric with respect to a diameter line that intersects the axis C (a line coinciding with the radial direction).

[0041] Following the description of the design of the first convex sections 6 and the second convex section 7, a detailed description of the two resonance suppression structures mentioned above will be given.

[0042] The first convex sections 6 are parts that form the first group 6G of convex sections and are provided projecting radially inwards from the inner surface 4f of the pipe section 4. The projection length of the first convex sections 6 with respect to the inner surface 4f of the pipe section 4 is specified to a length at which, in the holding state, there is no obstruction of the shaft bearing 2, as shown in Fig. 2 shown. In the present embodiment, the first convex sections 6 are provided on a front end section of the pipe section 4 on the side of the first direction.

[0043] As in Fig. As shown in Figure 4, the first convex sections 6 in the present embodiment have an inner end surface 6a facing in the second direction, an outer end surface 6b (end surface) facing in the first direction, and a circumferential surface 6c which, with respect to the inner end surface 6a and the outer end surface 6b, faces radially inwards towards the radially inner side. Through these surfaces 6a, 6b, 6c, the first convex sections 6 essentially form a rectangular shape at their intersection in the axial direction.

[0044] Each outer end surface 6b is a surface provided extending radially inwards from the inner surface of the tube 4f and forms, as shown in Fig. Figure 3 shows a partially annular plane extending circumferentially when viewed from the axial direction. Since the first convex sections 6 of the present embodiment lie at the front end section of the pipe section 4, the outer end surface 6b is continuous and essentially flush with the end surface of the pipe section 4 facing in the first direction.

[0045] The inner end surface 6a is a surface extending radially inwards from the inner surface of the tube 4f and, when viewed from the axial direction, forms a partially annular surface extending circumferentially. From the perspective of increasing the strength of the first convex sections 6, as shown in Fig. As shown in Figure 4, a radially outer part of the inner end surface 6a is inclined radially inwards. In this way, the thickness of a foot end section of the first convex sections 6 is increased, thus achieving a strength increase. The movement of the O-ring 5 in the first direction is restricted by its bearing against the inner end surface 6a of the first convex sections 6, which faces the O-ring 5.

[0046] Each circumferential surface 6c forms a curved surface extending axially and circumferentially. An end edge of the circumferential surface 6c on the side of the second direction is connected to an end edge of the inner end surface 6a on the radially inner side. Conversely, an end edge of the circumferential surface 6c on the side of the first direction is connected via an inclined surface 6d to the end edge of the outer end surface 6b on the radially inner side. In other words, the inclined surface 6d is provided on the first convex sections 6, connecting the outer end surface 6b and the circumferential surface 6c. The inclined surface 6d allows the O-ring 5 to be easily inserted between the two types of convex sections 6 and 7, and prevents damage to the O-ring 5 during insertion.

[0047] The second convex sections 7 are sections forming the second group 7G of convex sections and are provided projecting radially inwards from the inner surface 4f of the pipe section 4. The second convex sections 7 are located further in the second direction than the first convex sections 6 and are arranged at a distance from the first convex sections 6. The distance between the first convex sections 6 and the second convex sections 7 is specified as at least equal to or greater than the thickness of the O-ring 5 in the axial direction. From the perspective of allowing deformation of the O-ring 5 under load, they are more preferably specified as greater than the thickness of the O-ring 5.The projection length of the second convex sections 7 with respect to the inner surface 4f of the pipe section 4 is, as with the first convex sections 6, set to a length at which there is no obstruction of the shaft bearing 2 in the holding state.

[0048] The second convex sections 7 of the present embodiment are provided on a front end section of the tube section 4 on the side of the second direction and are provided at an axial position where they superimpose on the axial position of the surface section 51. As shown in Fig. 2 and Fig. As shown in Figure 5, the second convex sections 7 are of essentially rectangular shape at their cross-sectional surface in the axial direction and have an inner end surface 7a facing in the first direction and a circumferential surface 7c which is radially inward from the inner end surface 7a in the radial direction towards the radially inner side.

[0049] Each inner end surface 7a is a surface provided extending radially inwards from the inner surface of the tube 4f and forms, as shown in Fig. Figure 3 shows a partially annular surface extending circumferentially when viewed from the axial direction. From the perspective of increasing the strength of the second convex sections 7, as shown in Fig. As shown in Figure 5, a radially outer portion of the inner end surface 7a is inclined radially inwards. This increases the thickness of a foot end section of the second convex sections 7, thus increasing the strength. The movement of the O-ring 5 in the second direction is restricted by its contact with the inner end surface 7a of the second convex sections 7, which faces the O-ring 5. The circumferential surface 7c forms a curved surface extending axially and circumferentially, and its end edge on the side facing the first direction is connected to an end edge of the inner end surface 7a on the radially inner side.

[0050] In the present embodiment, the restricting section 8 is connected to the side of the second direction of the second convex sections 7. The second convex sections 7 thus also serve as leg sections to connect the pipe section 4 and the restricting section 8. In the present embodiment, the restricting section 8 is also connected to the pipe section 4, but the restricting section 8 and the pipe section 4 do not necessarily have to be connected. As in Fig. As shown in Figure 6, the restriction section 8, for example, when viewed from the side of the second direction, has the shape of a gear arranged coaxially with the axis C.

[0051] Recesses on the outer circumferential edge of the restricting section 8 (spaces between the teeth of the restricting section 8, if it is considered as a gear shape) coincide with the distances between two circumferentially adjacent second convex sections 7. A through hole h is arranged between two circumferentially adjacent second convex sections 7, which, as shown in Fig. 4 and Fig. Figure 6 shows the pipe section 4, which is divided by the restricting section 8 and the inner surface 4f of the pipe section 4. The through-hole h runs axially between two second convex sections 7 that are adjacent to each other circumferentially. Since, in the present embodiment, the multiple first convex sections 6 and the multiple second convex sections 7 are arranged alternately as discussed above, without overlapping each other circumferentially, the multiple first convex sections 6, when viewed from the axial direction, are arranged in a region that completely overlaps the through-hole h. In other words, the first convex sections 6 each lie within the region of the through-hole h.

[0052] As discussed above, in the support structure 1, the convex sections 6 and 7 of the two groups 6G and 7G, which have different circumferential lengths, are provided as the first resonance suppression structure. Since the natural frequencies of the first convex sections 6 and the second convex sections 7 differ from each other in this way, it is prevented that both the first convex sections 6 and the second convex sections 7 resonate with the vibration of the shaft bearing 2. Consequently, vibration suppression is achieved for the support structure 1 and the motor 10 to which the support structure 1 is applied. In the present embodiment, the circumferential length of the second convex sections 7 is set greater than the circumferential length of the first convex sections 6.In other words, when comparing the second convex section 7 with the smallest circumference and the first convex section 6 with the largest circumference, the circumference of the former is greater. This not only achieves the vibration suppression discussed above, but also increases stability during assembly.

[0053] More precisely, when the shaft bearing 2 is inserted, it is inserted in a state where the O-ring 5 is attached to the pipe section 4. This causes the O-ring 5 to be pressed in the second direction, exerting a load on the second convex sections 7. In the present embodiment, the circumferential length of the second convex sections 7, located on the side where the O-ring 5 is pressed against the pipe section 4 when the shaft bearing 2 is inserted, is set to be greater than the circumferential length of the first convex sections 6. Since this increases the strength of the second convex sections 7 more than that of the first convex sections 6, buckling or deformation of the second convex sections 7 during insertion of the shaft bearing 2 is prevented.Furthermore, since the movement of the O-ring 5 in the second direction is restricted when the shaft bearing 2 is inserted by the second convex sections 7, whose circumferential length is greater than the circumferential length of the first convex sections 6, dislodging the O-ring 5 in the second direction is prevented. Consequently, increased stability is achieved during assembly.

[0054] In the support structure 1, the second resonance suppression structure consists of the multiple convex sections 6, 7 of groups 6G, 7G with unequal dimensions. In the present embodiment, the multiple second convex sections 7 of the second group 7G of convex sections from groups 6G, 7G constitute the second resonance suppression structure. The multiple second convex sections 7 are thus provided with unequal dimensions. As a result, the respective natural frequencies of the multiple second convex sections 7 and the second convex sections 7 arranged circumferentially adjacent to these second convex sections 7 differ from one another, thereby further suppressing the resonance associated with the vibration of the shaft bearing 2.

[0055] Furthermore, in the present embodiment, the multiple second convex sections 7 are arranged asymmetrically as the second resonance suppression structure. In other words, the second group 7G of convex sections comprises several asymmetrically arranged second convex sections 7. By arranging the multiple second convex sections 7 asymmetrically, it is prevented that the multiple second convex sections 7 connected via the tube section 4 as a whole (as the second group 7G of convex sections) resonate with the vibration of the shaft bearing 2.

[0056] In the present embodiment, the circumferential length is defined differently for each of the multiple second convex sections 7. This results in the natural frequencies of all the second convex sections 7 differing from one another, thereby further suppressing the resonance associated with the vibration of the shaft bearing 2. Due to this definition of the circumferential length, the multiple second convex sections 7 are necessarily arranged asymmetrically. It is also preferred that the multiple second convex sections 7 are not arranged sequentially when viewed from the axial direction, either clockwise or counterclockwise, starting with a section of short circumferential length, but rather are arranged randomly (in a disordered manner).

[0057] In contrast, the circumferential length of each of the multiple first convex sections 6 is fixed the same. Since, in the present embodiment, the first convex sections 6 are provided without circumferential spacing between two adjacent second convex sections 7, as discussed above, the spacing of the multiple second convex sections 7 is, in other words, fixed such that their circumferential lengths are equal. The circumferential length of each of the multiple second convex sections 7 is fixed differently, and their arrangement and circumferential length are fixed such that their spacings are asymmetrical.

[0058] By ensuring that the circumferential length of the multiple convex sections 6, 7 of one of the two groups 6G, 7G of convex sections (here, the multiple first convex sections 6) is the same, the size of the die of the mold used for the one-piece forming of the tube section 4, the first convex sections 6, and the second convex sections 7 from plastic can be uniform, thus improving productivity. Furthermore, by arranging the spacing of the multiple second convex sections 7, and therefore also the multiple first convex sections 6, asymmetrically, the multiple first convex sections 6 connected via the tube section 4 are prevented from resonating as a whole (as the first group 6G of convex sections) with the vibration of the shaft bearing 2.

[0059] The six second convex sections 7 of the present embodiment are designated, in order of their circumferential length, as first second convex section 7-1, second second convex section 7-2, third second convex section 7-3, fourth second convex section 7-4, fifth second convex section 7-5, and sixth second convex section 7-6. A central angle of a circular arc corresponding to the circumferential length of the first convex sections 6, which form a partial circle when viewed from the axial direction, is designated α. The central angles of the circular arc corresponding to the circumferential length of the second convex sections 7, which form a partial circle when viewed from the axial direction, are designated, starting with the smallest, β1, β2, β3, β4, β5, and β6, respectively.

[0060] In the present embodiment, the circumferential lengths of the six first convex sections 6 and the six second convex sections 7 are set such that α < β1 < β2 < β3 < β4 < β5 < β6 is satisfied. The central angle α of the first convex sections 6 (i.e., the circumferential length of the first convex sections 6) is set to a value that, at least by all first convex sections 6 together, prevents the O-ring 5 from being pulled out in the first direction. The six second convex sections 7 are, as in Fig. The 7 shown are not arranged clockwise or counterclockwise, starting with one short in circumference, but are arranged randomly (unordered).

[0061] As an example, in the present embodiment, as in Fig. Figure 7 shows the upper right first second convex section 7-1 and the lower left second second convex section 7-2 arranged such that the axis C lies between them. The second second convex section 7-2, the third second convex section 7-3, and the fourth second convex section 7-4 are also arranged adjacent to each other, and the first second convex section 7-1, the fifth second convex section 7-5, and the sixth second convex section 7-6 are arranged adjacent to each other.

[0062] The second convex sections 7, with the exception of the first second convex section 7-1 and the second second convex section 7-2, are arranged such that the difference between the sum of the central angles of two second convex sections 7 that lie on one side (for example, the clockwise side) with respect to the first second convex section 7-1 in the circumferential direction, and the sum of the central angles of two second convex sections 7 that lie on the other side (for example, the counterclockwise side) with respect to the first second convex section 7-1 in the circumferential direction, is minimal.In the present embodiment, the sixth second convex section 7-6 and the third second convex section 7-3 are arranged adjacent to the first second convex section 7-1 on the side clockwise, and the fifth second convex section 7-5 and the fourth second convex section 7-4 are arranged adjacent to the first second convex section 7-1 on the side counterclockwise.

[0063] In a different arrangement of the multiple second convex sections 7 of the present embodiment, the first second convex section 7-1, whose central angle is the smallest, is arranged such that it is not adjacent to the second and third second convex sections 7-2, 7-3, with the second smallest and third smallest central angles, respectively. Likewise, the second convex section 7-6, with the largest central angle, is arranged such that it is not adjacent to the fourth and fifth second convex sections 7-4, 7-5, with the second largest and third largest central angles, respectively. This allows the O-ring 5 to be held even more securely against dislodging, and prevents breakage of second convex sections 7 with a comparatively small circumference (for example, the first second convex section 7-1).

[0064] As discussed above, the constraint section 8 is a part that restricts the movement of the shaft bearing 2. The constraint section 8 is connected to the side of the second direction of each of the multiple second convex sections 7 and connects the multiple second convex sections 7 to each other. As in Fig. As shown in Figure 2, the constraint section 8 extends with respect to the multiple second convex sections 7 (the second group 7G of convex sections) to the radially inner side and forms a surface section which, in the holding state, is located opposite the end face of the shaft bearing 2. The constraint section 8 restricts the movement of the shaft bearing 2 in the second direction by means of this surface section. The constraint section 8 can restrict the movement of the shaft bearing 2 in the second direction by bearing against the end face of the shaft bearing 2 with its surface section, or, as shown in Figure 2, it can... Fig. 2 shown, by means of a spring 9 which is inserted between the surface section and the end surface of the shaft bearing 2, the movement of the shaft bearing 2 in the second direction is restricted. [3. Operation and Effect] (1) In the support structure 1 and the motor 10 discussed above, the pair of groups 6G, 7G of convex sections, which project radially inwards from the inner surface 4f of the tube section 4, are arranged such that the O-ring 5 lies axially between them. The groups 6G, 7G of convex sections each have the same number of convex sections 6, 7. The multiple second convex sections 7 of the second group 7G of convex sections from the two groups 6G, 7G of convex sections are provided with unequal dimensions. This allows for a deviation in the natural frequencies of the adjacent second convex sections 7, thereby suppressing the resonance associated with the vibration of the shaft bearing 2.Consequently, vibration suppression can be achieved in the course of vibrations of the shaft bearing 2, and thus a device (in particular a motor 10) with improved quiescent properties can be provided. (2) By arranging the multiple second convex sections 7 asymmetrically, it is possible to prevent the multiple second convex sections 7 as a whole from resonating with the vibration of the shaft bearing 2. (3) If the circumferential length of all the several second convex sections 7 is different, a deviation of the natural frequencies of all the second convex sections 7 can be caused, which can further suppress the resonance associated with the vibration of the shaft bearing 2. (4) According to the support structure 1 shown above, the restraint section 8 restricts the movement of the shaft bearing 2 in the second direction. Consequently, the shaft bearing 2 can be held more stably. Furthermore, by providing the several second convex sections 7, which are more sensitive to the vibration of the shaft bearing 2 via the restraint section 8, with unequal dimensions and arranging them asymmetrically, resonance associated with the vibration of the shaft bearing 2 can be suppressed even more effectively. (5) If the restrictive section 8 is provided and the axially continuous through-hole h is arranged between two circumferentially adjacent second curved sections 7, air can also be drawn in through the through-holes h to cool the shaft bearing 2. Since the shaft bearing 2 can thus be adequately cooled by utilizing the through-holes h, the service life of the shaft bearing 2 can be extended. (6) In the holding structure 1 discussed above, the first convex sections 6, when viewed from the axial direction, are arranged within an area of ​​overlap with the through-holes h. In other words, the first convex sections 6, when viewed from the axial direction, lie within the areas of the through-holes h and are provided in such a way that they do not overlap the second convex sections 7. Since the tube section 4, the first convex sections 6, and the second convex sections 7 can thus be formed in one piece without providing an undercut section, productivity can be improved. Furthermore, forced removal during the forming of the tube section 4, the first convex sections 6, and the second convex sections 7 is avoided, thereby increasing the precision of the convex sections 6 and 7.

[0065] The circumferential length of all the first convex sections 6 is assumed to be the same. Since this allows the size of the die of the forming tool used in the one-piece forming of the pipe section 4, the first convex sections 6, and the second convex sections 7 to be uniform, an improvement in productivity can be achieved.

[0066] (7) In the support structure 1 discussed above, the several first convex sections 6 are also arranged asymmetrically. This also prevents the several first convex sections 6 connected via the tube section 4 from resonating as a whole with the vibration of the shaft bearing 2.

[0067] (8) In the support structure 1 discussed above, the pipe section 4 has the surface section 51, which extends radially outwards from the outer surface 4g of the pipe, and the multiple ribs 53, which project axially from the surface section 51 and extend radially outwards from the outer surface 4g of the pipe. The multiple ribs 53 are arranged at positions of the same phase as the multiple second convex sections 7 of the second group 7G of convex sections from the two groups 6G, 7G of convex sections. This allows the strength of a component provided on the pipe section 4 (here the end bell 50) and the second convex sections 7 to be increased. [4. Other]

[0068] The configuration of the mounting structure 1 and the motor 10 described above is merely an example, and there is no limitation to the configuration discussed above. The device to which the mounting structure 1 is applied is not limited to the motor 10, as long as it is a device on which at least one shaft bearing 2 is provided. The mounting structure 1 of the present invention is particularly advantageous for a device for which vibration suppression is required.

[0069] In the support structure 1 discussed above, the perimeter length of the several second convex sections 7, which are provided with unequal dimensions, is defined differently; however, it is sufficient if at least the perimeter length of circumferentially adjacent second convex sections 7 of the several second convex sections 7 differs. For example, some of the several second convex sections 7 may have the same perimeter length. The several second convex sections 7 do not need to be arranged asymmetrically.

[0070] In the support structure 1 discussed above, the perimeter length of each of the several first convex sections 6 is fixed, but the perimeter length of all first convex sections 6 need not be the same, or the perimeter length of some of the first convex sections 6 may be the same, while the perimeter length of the remaining first convex sections 6 may be different. The several first convex sections 6 need not be arranged asymmetrically.

[0071] Instead of the multiple second convex sections 7 of the second group 7G of convex sections, the multiple first convex sections 6 of the first group 6G of convex sections with unequal dimensions may also be provided. In this case, the multiple first convex sections 6 are preferably arranged asymmetrically. Both the multiple first convex sections 6 and the multiple second convex sections 7 with unequal dimensions may also be provided. The support structure 1 need not include the first resonance suppression structure. The size relationship between the circumferential lengths of the first convex sections 6 and the second convex sections 7 is not limited to that described above.

[0072] In the support structure 1 discussed above, the multiple first convex sections 6 and the multiple second convex sections 7 are arranged alternately without circumferential spacing. However, a circumferential spacing can be provided between the multiple first convex sections 6 and the multiple second convex sections 7. Thus, when viewed from the axial direction, the first convex sections 6 can be arranged within a portion of the area of ​​overlap with the through-holes h. If the holding force and resonance suppression effect for the pipe section 4, the first convex sections 6, and the second convex sections 7 are of greater importance than productivity, the first convex sections 6 and the second convex sections 7 can be arranged overlapping each other when viewed from the axial direction.

[0073] It is sufficient if the several first convex sections 6 and the several second convex sections 7 are provided projecting radially inwards from the inner surface of the tube 4f and are spaced apart from each other in the circumferential direction, and they are not limited to the shape described above. It is sufficient if the tube section 4 is a tube shape into which the shaft bearing 2 and the O-ring 5 can be inserted towards the radially inner side, and it is not limited to the shape described above.

[0074] If the shaft bearing 2 is inserted into the pipe section 4 from the side of the second direction to the side of the first direction, i.e., if the front side discussed above is the side of the second direction and the rear side is the side of the first direction, the first group 6G of convex sections of the retaining structure 1 described above can also be defined as the “second group of convex sections” of the claims. In this case, the confining section 8 can be provided as a part that connects the multiple first convex sections 6. If no axial positioning of the shaft bearing 2 is required, the confining section 8 can also be omitted. It is also sufficient if the confining section 8 at least restricts the rearward movement of the shaft bearing 2, and it is not limited to the shape described above.

[0075] The surface section 51 and the ribs 53 of the pipe section 4 can also be omitted. The "pipe section" from the claims can therefore be provided separately from the end bell 50 and the housing 40. The ribs 53 can be arranged at positions of the same phase as the several first convex sections 6.

[0076] In the embodiment described above, the retaining structure 1 is applied to the pipe section 4 of the end bell 50; however, the retaining structure 1 can also be applied to the pipe section 3 on the side of the housing 40. In this case, the shaft bearing 2 is inserted from the side opposite in the axial direction into the radial interior of the pipe section 3. The other axial direction (in Fig. 1 above) is therefore, when considering the direction of insertion of the shaft bearing 2 into the pipe section 3, the front side (the side of the first direction) and one axial direction (in Fig.1 below) is, when considering the direction of insertion of the shaft bearing 2 into the pipe section 3, at the rear (the side of the second direction). By providing a pair of convex sections on the pipe section 3, similar to the pair of convex sections 6G, 7G of the embodiment above, the shaft bearing 2 can be adequately held, and at the same time, any vibration associated with the vibration of the shaft bearing 2 (resonance vibration) can be suppressed. When the retaining structure 1 is applied to the pipe section 3, a retaining section, a through hole, an inclined surface, and ribs can be provided, just like the confining section 8, the through hole h, the inclined surface 6d, and the ribs 53. When the retaining structure 1 is applied to the pipe section 3 of the housing 40, projecting ribs can be provided, for example, just like the ribs 53 from the bottom section 42. Explanation of reference symbols 1 Support structure (shaft bearing support structure) 2 shaft bearings 3 Pipe section 4 Pipe section 4f inner pipe surface 4g outer surface area of ​​the tube 5 O-ring 6 first convex section (convex section) 6G group of first convex sections (group of convex sections) 7 second convex section (convex section) 7G group of second convex sections (group of convex sections) Section 8 Restriction 10 Motor 20 Rotor 21st wave 30 Stator 40 Enclosure 50 End bell 51 Area section 53rd rib C axis h through hole QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 4186148

[0003]

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