JP6981959B2 - Magnetic wheel for electric motors - Google Patents

Description

The present invention has a stator (19) and a rotatably bearing rotor (18) in a housing, and has a magnetic wheel (2) mounted on the rotor (18) so that it cannot rotate relative to each other. Regarding the motor (1).

German Patent Publication No. 19823640 describes a magnetic wheel mounted on a shaft, wherein the metal shaft and the plastic-bonded permanent magnet have different coefficients of thermal expansion, but the press. Bonds are formed. The problem is that the magnetic wheel consists of two axial parts, in which case the first part is cut out towards the axis and the second part is press-mounted as a reinforcing member by a ring-shaped auxiliary body. It will be solved by. The two axial portions require a larger axial built-in space. In addition, the magnetic wheel is fixed only in the short part on one side, despite the increased built-in length. In addition, this arrangement requires an additional joining process to attach the reinforcing means.

German Patent Publication No. 19823640

Therefore, the subject of the present invention is that in an electric motor with a magnetic wheel, it is easily formable and mountable, in which case it requires only a small axial length and is accurate for a stator-fixed sensor. It is to make it possible to associate and adjust the position in various axial directions.

According to the present invention, this problem is solved by the feature of the device claim 1 and the feature of the method claim 22. The magnetic wheel (2) consists of a magnet ring (7) and a support (3) designed for magnetic properties, the support of which is subject to particularly high demands for rigidity and heat resistance. It is proposed to consist of a simple plastic material without magnets. Since the support (3) has a fixing means (4) that extends axially into the notch (12) of the rotor (18) and fits into the notch (12), the rotational interlocking of excellent shape coupling is possible. Given.

The development of the present invention is shown in the sub-claims. It has been revealed that it is preferable that the support (3) has one mounting portion or a plurality of mounting portions (6) supported by the shaft (25) of the rotor (18). This support prevents the magnetic wheel (2) from tending to tilt or being tilted and mountable.

In order to be able to permanently guarantee this effect, the one or more mounting portions (6) have one / multiple mounting surfaces (34) adapted to the outer surface of the cylinder. Then, the mounting surface is directly attached to the shaft (25). Since the shaft (25) also has a cylindrical outer surface, it is provided with one or more compact mounting surfaces (34) over a large area, which are exposed to shape changes even under vibration load. It does not lose the advantages mentioned above.

In that case, preferably, three or more mounting portions (6) are provided, and sleeves (29) are continuously provided in the mounting portion in the radial direction, or in the mounting portion (6). The mounting portion has a sleeve shape. This provides accurate centering of the magnetic wheel (2) on the axis (25).

On the one hand, easy installation without the risk of damage to the magnetic wheel (2), on the other hand, one or more to achieve the least playful coupling between the magnetic wheel (2) and the shaft (25). The mounting portion (6) is dimensionally designed according to the transition fit together with the shaft (25).

According to a particularly preferred development of the present invention, the magnetic wheel (2) has one or more shaft stoppers (36), which project axially from the magnetic wheel. One or more shaft stoppers (36) are axially continuous with one or more mounting portions (6). Thereby, when mounted, the final position of the magnetic wheel (2) can be adjusted as defined by the axial pressure supply.

A ring disk-shaped hub (30) is connected radially to the sleeve (29) or to the sleeve-shaped mounting portion (6). The hub (30) is used to bridge the radial spacing between the shaft (25) or mounting section (6) and / or the sleeve (29) and the magnet ring (7), in which case. Material deposition is minimized, which would result in deformation after the injection molded material has hardened. Thus, because the hub (30) is disc-shaped, the entire support (3) has approximately equal wall thickness within its various regions.

Preferably, the hub (30) is radially continuous with the magnet accommodating ring (9). Further, the magnet accommodating ring (9) is axially widened by a ring wall (37) at its axial end, respectively, in which case a groove is formed between the magnet accommodating ring (9) and the ring wall (37). (33) is formed. This groove (33) is used as a shaft fixing portion for the magnet ring (7). Due to the ring shape of the magnet ring (7), the magnet ring is further reliably held in the radial direction.

Depending on each form, at least a portion of the magnet ring (7) can be accommodated in the groove (33), or the magnet ring (7) can extend radially beyond the groove (33). Further, the magnet ring (7) extends axially outside the groove (33) by a distance such that the axial boundary between the ring wall (37) and the magnet ring (7) is located in one plane. Can be done. This results in a wider magnet ring (7), which has a greater probability of directly facing the magnetic wheel (2). To allow this effect to be further enhanced, each magnet ring (7) can also extend further beyond the ring wall (37), depending on whether the surrounding geometry allows it. ..

The fixing means (4) is at least partially axially continuous with the hub (30). But also the fixing means is at least partially axially magnet-accommodating ring (9) according to the diameter of the fixing means (4) and how the corresponding notch (12) of the rotor (18) is dimensionally designed. ) Can also be continued.

Other forms of the fixing means (4) are particularly effective, such that the fixing means taper off toward a region distant from the magnetic wheel (2). This, on the one hand, facilitates the joining process in the notch (12), and on the other hand, the press-fitting increases with the press-fitting depth. However, since the taper is relatively small, the axial length of the magnetic wheel (2) occurs without problems over a relatively large axial region.

This effect is such that the fixing means (4) has a notch (14) along its axial extension, the notch being, for example, a notch (40), a slit (32) and / or a hollow chamber (31). Being able to form is further improved. This is because it provides the desired flexibility.

The coarser the joint surface, the better the bond by force tightening. Therefore, it is meaningful that the fixing means (4) is accommodated in the notch (12) of the rotor thin plate packet (26) by force coupling in the axial direction and by shape coupling in the rotational direction.

A spring (42) is placed between the rotor lamella packet (26) and the magnetic wheel (2) to ensure that the magnetic wheel (2) stays in its axial position, and the spring is the magnetic wheel. (2) is brought into axial pressure contact with the second groove ball bearing (15). It is meaningful that the spring (42) is made of the material of the support (3) and is integral with it so that it does not increase the number of parts and the labor of mounting.

The second solution of the problem is achieved by a method having the following method steps:
a) Prepare a rotor assembly consisting of a press-mounted rotor lamella packet (26) with a shaft (25) and an attached permanent magnet (27); b) a magnetic wheel (2) in a rotor lamella packet (26). 26) Pre-mounted in the notch (12); c) Press-mounted the grooved ball bearing (15) onto the shaft (25) to the shaft end and the inner ring (39) of the grooved ball bearing (15). ) Is adjusted, in which case the magnetic wheel (2) is further press-fitted into the notch (12) of the rotor thin plate packet (26). By this measure, the manufacturing error of the individual parts of the electric motor (1), which affects the position of the magnetic sensor, can be compensated in an elegant manner.

For further assembly, the permanent magnet (27) and the magnet ring (7) of the magnetic wheel (2) are magnetized at the same time. This eliminates additional method steps.

Then, a stator assembly consisting of a housing cup (10) having a mounted stator (19) and a mounted first groove ball bearing (8) used as a fixed bearing is prepared, and the stator assembly is formed. Mounted on the rotor assembly, in which case a sleeve-shaped tool is attached to the inner ring (39) of the first grooved ball bearing (8), the grooved ball bearing on the shaft (25). Press mounted as specified.

Next, examples of the present invention will be described in detail with reference to examples.

It is a front view which shows the 1st Embodiment of a magnetic wheel. It is a perspective view which shows by breaking the magnetic wheel of FIG. It is a perspective view which shows the display of FIG. 2 from another viewpoint. It is sectional drawing which shows the 1st Embodiment of a magnetic wheel. It is another cross-sectional view which shows the magnetic wheel. It is another front view which shows the magnetic wheel. Shows the magnetic wheel attached to the rotor. A second embodiment of the magnetic wheel is shown. A modification of the second embodiment of the magnetic wheel is shown. The electric motor having the magnetic wheel of 1st Embodiment is shown.

Note: In drawings and description, reference numerals with apostrophes and similar reference numerals without apostrophes refer to individuals with equal names. It is a use in other embodiments, prior art, and / or a simple substance is a modification. Claims, specification introductions, reference code lists and summaries have only reference codes without apostrophes for brevity.

1 to 6 show a first embodiment of the magnetic wheel 2, which comprises a support 3 and a magnet ring 7, from various viewpoints. The support 3 is composed of a ring disk-shaped hub 30, to which six fixing means 4, a central sleeve 29, and a magnet accommodating ring 9 are continuous. The magnet accommodating ring 9 (see FIG. 2) is radially connected by two ring walls 37 separated from each other. The magnet accommodating ring 9 and the ring wall 37 form a groove 33 (see FIG. 2) that is open outward in the radial direction from each other. The groove 33 is filled with the magnet ring 7. The magnet ring 7 forms a cylindrical outer contour that extends radially beyond the ring wall 37. The axial boundary of the magnet ring 7 and the axial boundary of the ring wall 37 are located in one plane. The sleeve 29 projects axially with respect to the magnet ring 7 and the ring wall 37. The sleeve 29 is continuous with three mounting portions 6 arranged radially inward at an angular interval of 120 ° with respect to each other, and these are used as supporting means. These mounting portions have a radial inner mounting surface 34 adapted to the outer surface of the cylinder. They form a transitional fit with the shaft 25 (see FIG. 9) in the assembled state. The mounting portions 6 each have a shaft stopper 36 (see FIG. 2) in the axial direction. These are used for annexing the second groove ball bearing 15 (see FIG. 9). The shaft stopper 36 projects axially with respect to the sleeve 29. The fixing means 4 has the shape of a sleeve 29 having a slit that gradually becomes thinner, and has a hollow chamber 31 and a slit 32 that faces inward, respectively. The fixing means 4 is used as a rotation prevention for the magnetic wheel 2. The chamfer 35 (see FIGS. 3 and 4) provided at the end of the fixing means 4 and its taper also facilitate the introduction of the rotor thin plate packet 26 into the notch 12 (see FIG. 9). The taper further provides a fixed force-tightening bond within this notch 12. In that case, the slit 32 allows some flexibility of the fixing means 4 so that its diameter is slightly reduced to fit the notch 12 in the thin plate packet. The fixing means 4 extends radially from the sleeve 29 over the hub 30 to the magnet accommodating ring 9. The support 3 is integrated with the sleeve 29, the hub 30, the fixing means 4, the mounting portion 6, and the magnet accommodating ring 9. The magnet ring 7 consists of a plastic-bonded permanent magnet 27 (see FIG. 1), a rare earth magnet such as NdFeB. The magnetic wheel 2 is formed by a two-component injection molding method, in which case a support 3 made of a plastically deformable plastic material is first initially molded in a first cavity and then a plastic-bonded permanent magnet. The material magnet ring 7 is joined to the initial molded support 3 in the second cavity. The material of the support 3 is not subject to very high demands. This is because the press coupling with the shaft 25 can be omitted based on the shape coupling with the rotor thin plate packet 26. The mounting portion 9 prevents the magnetic wheel 2 from being tilted. FIG. 1 suggests a conical mold release slope 41, which facilitates mold release from the injection mold. The mounting section 6 does not have a release slope 41 to provide a defined mounting surface.

FIG. 7 shows the magnetic wheel 2 of the first embodiment attached to the rotor 18 in two cutting planes tilted 150 ° with respect to each other (see line AA in FIG. 1). The fixing means 4 integrated with the support 3 extends into the axially parallel notch 12 of the rotor thin plate packet 26, and is held in the notch 12 by force coupling. The mounting portion 6 of the magnetic wheel 2 integrated with the support 3 is mounted on the shaft 25. As a result, the tilt of the magnetic wheel 2 is prevented. The shaft stopper 36 is axially attached to the inner ring 39 of the groove ball bearing 15. Thereby, when joining the grooved ball bearings 15, it is possible to adjust the press-fitting depth of the fixing means 4 in the notch 12. In principle, the number of fixing means 4 can be freely selected, but it is recommended to provide at least two, preferably three or more fixing means 4.

FIG. 8 stylizes a second embodiment of a magnetic wheel 2'with a support 3'and a magnet ring 7'. Here, the two fixing means 4'are integrated with the support 3', and the fixing means extend in parallel with the axis so as to be separated from the support 3'. Each of the fixing means 4'is provided with four tapering ribs 38, which form a cross-shaped arrangement and are separated from each other by a notch 40. Here, the mounting portion 6 has been removed for brevity, but can be formed in the same manner as in the first embodiment. A ring-shaped mounting portion 6'can also be used instead of the discrete mounting portion.

FIG. 9 shows a modification of the second embodiment of the magnetic wheel 2 "in which the spring 42 made of plastic is integrated with the support 3". The spring 42 consists of two rings 13 that are separated from each other and coupled to each other via the web 17. Another web 17 couples the first ring 13 to the support 3 ". The web 17 located between the rings 13 is between the support 3" and the sensor 43 (see FIG. 10). It is displaced by 90 ° with respect to the web 17 arranged in. The outer ring 13 is axially continuous with two protrusions 23 that are displaced by an angle of 90 ° with respect to the web 17 connecting the rings 13. The protrusion 23 is used as a defined splicing surface for splicing the rotor thin plate packet 26. Due to the angular displacement of the webs 17 with respect to each other and the protrusions 23 with respect to the webs 17, the region of the ring 13 between the webs 17 is spring elastically displaceable in the axial direction. 42 flexibility is possible. The spring 42 always ensures that the magnetic wheel 2 "is attached to the second groove ball bearing 15.

FIG. 10 shows an assembly drawing of the electric motor 1, which is an electronically rectified DC motor, which is a rotor 18 with a permanent magnet 27 and a stator around which windings 24 are wound. It has a 17 and a housing. The housing comprises a bearing shield 20 and a housing cup 10. The rotor 18 is composed of a smooth shaft 25, a rotor thin plate packet 26, a permanent magnet 27 and a magnetic wheel 2, the magnetic wheel of which is held on a support 3 (see FIGS. 1 to 6), wherein the support is held. It is axially press-fitted into the notch 12 of the rotor thin plate packet 26 via the fixing means 4. The sensor 43 cooperates with the magnetic wheel 2 and the sensor is arranged radially with respect to the magnetic wheel 2 on the conductor substrate 21; instead, an axial arrangement is also possible. The conductor substrate 21 is formed as an injection-coated conductor thin plate, which has a connector 22. Further, a first grooved ball bearing 8 fixed by a spring steel disc 5, a second grooved ball bearing 15, a cover cap 16 fixed in the notch 14, a flanged gear pump 28 and a flanged gear pump 28. The stator thin plate packet 11 is shown. When mounting the magnetic wheel 2, the axial position with respect to the rotor 18 can be adapted to each actual dimension within a predetermined limit. A shaft stopper 36 (see FIGS. 1 to 6) is used for this purpose, and the shaft stopper can be supported by the inner ring 39 of the second groove ball bearing 15. In this way, an accurate positional correspondence with respect to the sensor 43 is formed. The magnetic wheel 2 and the rotor 18 have three N poles and three S poles, respectively.

1 Electric motor 2 Magnetic wheel 3 Support 4 Fixing means 5 Spring steel disk 6 Mounting part 7 Magnet ring 8 First groove ball bearing 9 Magnet accommodating ring 10 Housing cup 11 Stator thin plate packet 12 Notch 13 Ring 14 Notch 15 Second groove ball bearing 16 Cover cap 17 Web 18 Rotor 19 Stator 20 Bearing shield 21 Conductor board 22 Connector 23 Protrusion 24 Winding 25 Axis 26 Rotor thin plate packet 27 Permanent magnet 28 Gear pump 29 Sleeve 30 Hub 31 Hollow chamber 32 Slit 33 Groove 34 Mounting surface 35 Chamfering 36 Shaft stopper 37 Ring wall 38 Rib 39 Inner ring 40 Notch 41 Detachable slope 42 Spring 43 Sensor

Claims (17)

A stator (19), a rotor (18) which is axially supported rotatably by Mizokatachidama bearing (15) in the housing, a rotationally fixed through a shaft (25) to said rotor (18) In an electric motor (1) having a magnetic wheel (2) attached to
The magnetic wheel (2) has a support (3) made of a plastic material and a magnet ring (7), and the support (3) has a fixing means (4) and one or more support portions (6). a, and said support (3) is attached to the rotor sheet packet (26) of said rotor (18) via a spring (42),
Wherein said notch (12) has a force coupled fitted axially into, and the magnetic wheel (2) is the spring of the rotor sheet packet (26) of the fixing means (4) is the rotor (18) (42) is axially pressure-welded to the grooved ball bearing (15).
Said magnetic wheel front Symbol support (6) and bears against directly to said shaft (25) (2) is supported in the radial direction the shaft (25),
Said magnetic wheel (2) is an electric motor (1) which by being axially fixed and radially, the shaft can be inclined against the (25) is prevented, characterized in that. It said support portion (6) has one support surface radially inwardly (34), according to claim 1, wherein the support surface (34) is spliced directly to said shaft (25), characterized in that Electric motor (1). Said support (3),
Has 3 or more of the supporting part (6), and the three or more of the supporting portions sleeve radially (6) (29) is continuous, or,
Prior Symbol support (6), the support (6) is a sleeve-shaped,
The electric motor (1) according to claim 1 or 2. Said support (3), the has one or more axes stopper for adjusting the axial position of the magnetic wheel (2) (36), the shaft the shaft stopper from said support (3) The electric motor (1) according to any one of claims 1 to 3, wherein the electric motor projects in a direction. The electric motor (1) according to claim 4, wherein the one or more shaft stoppers (36) are axially continuous with the one or more support portions (6). Said magnetic wheel (2) is supportable axially inner ring (39) of said through said shaft stopper (36) Mizokatachidama bearing (15), according to claim 4 or 5, characterized in that The electric motor (1) according to the above. The support (3) has a ring disk-shaped hub (30) that is continuous in the radial direction on the sleeve (29) or on the sleeve-shaped support portion (6). Item 5. The electric motor (1) according to any one of Items 3 to 6. The electric motor (1) according to claim 7, wherein the support (3) has a magnet accommodating ring (9) that is radially continuous with the hub (30). In the magnet housing ring (9) is an end portion in the axial direction, has a widened radially respectively the ring wall (37), the groove between the magnet housing ring (9) and the ring wall (37) The electric motor (1) according to claim 8, wherein (33) is formed. The electric motor (1) according to claim 9, wherein at least a part of the magnet ring (7) is housed in the groove (33). The electric motor of claim 10, wherein the magnet ring (7) extends radially beyond the grooves (33), it is characterized by (1). Position the ends of the axial direction within one plane in the outside of the groove (33) of the groove (33) the magnet ring and the end portion of the opposite axial direction (7) of the ring wall (37) The electric motor (1) according to claim 11, wherein the electric motor (1) is provided. The electric motor (1) according to any one of claims 7 to 12, wherein the fixing means (4) is at least partially continuous with the hub (30) in the axial direction. .. The electric motor according to any one of claims 8 to 12, wherein the fixing means (4) is at least partially continuous with the magnet accommodating ring (9) in the axial direction. 1). Said fixing means (4) comprises a magnetic wheel (2) electric motor according to any one of claims 1 14, toward the spaced region has increasingly thinner, characterized in that from (1 ). Said fixing means (4) is, Bruno pitch (40) along the extension of the axial direction, 15 from claim 1 are also slits (32) has a hollow chamber (31), characterized in that The electric motor (1) according to any one of the above items. The electric motor (1) according to any one of claims 1 to 16, wherein the spring (42) is made of the material of the support (3) and is integrated with the spring (42).

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