A method for manufacturing a magnetic gear modulator of a coaxial magnetic gear

Abstract

The invention relates to a method for manufacturing a magnetic gear modulator of a coaxial magnetic gear. The magnetic gear modulator of a coaxial magnetic gear is manufactured by injection molding a modulator holder on angularly spaced pole parts made of magnetically permeable material. The pole parts are initially connected by a support ring, or held by a fixture. The modulator holder is preferably a thermally conductive reinforced fiber filled plastic, carbon fiber plastic, carbon fiber filled plastic material, glass material, or high performance composite plastic molding material. After molding, the outer and / or inner portions of the molding material and, if present, the support ring are machined away, preferably exposing both the inner and outer faces of the pole parts embedded in the modulator holder. Manufacturing the magnetic gear modulator with injection molding on the connected support ring and pole parts reduces cost, and the carbon fiber plastic modulator holder increases strength.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 202280001533.4, filed on February 4, 2022, entitled "Injection Molded Modulator Support Holder".

[0002] Cross-references to related applications

[0003] This application claims priority to U.S. Provisional Patent Application Serial No. 63 / 145,856, filed February 4, 2021, and U.S. Patent Application Serial No. 17 / 665,342, filed February 4, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0004] This invention relates to magnetic power transmission devices, and more particularly to magnetic gear modulators (MGMs) for coaxial magnetic gears (CMGs). Background Technology

[0005] A CMG typically consists of an inner permanent magnet (PM) rotor and an outer permanent magnet (PM) rotor with alternating north and south pole permanent magnet pairs. The MGM is the central rotor located between the inner and outer rotors and includes magnetic pole components situated between the PM pairs of the inner and outer rotors. The ratio of the CMG is defined by the ratio of the PM pairs in the inner and outer rotors. The number of pole components in the MGM is the sum of the number of PM pairs in the inner and outer rotors. For example, with four PM pairs in the inner rotor and ten PM pairs in the outer rotor, the number of pole components in the MGM is 14. The CMG ratio will be ten to four, or 2.5:1, where the outer rotor rotates slower than the inner rotor. The MGM is the core of the CMG and also presents the greatest challenge for cost-effective production.

[0006] The lessons learned in the manufacture of high specific torque coaxial magnetic gears, presented by Zachary Cameron et al. at the 75th Annual VFS Forum and Technology Show in Philadelphia on May 16, 2019, describe the modulator pole rings machined after assembly or casting. Unfortunately, known methods for manufacturing MGMs are very expensive. The lessons learned in the manufacture of high specific torque coaxial magnetic gears are presented hereby cited in this paper.

[0007] Other known methods include manufacturing MGMs with a 1 mm to 2 mm thin strip that holds the modulator poles in place without requiring post-processing of the pole holding strip. Ideally, the thinner the air gap, the higher the CMG performance, thereby increasing torque and reducing iron loss. Unfortunately, for many applications, the thin strip lacks strength. Summary of the Invention

[0008] This invention addresses the aforementioned and other needs by providing a magnetic gear modulator (MGM) with a coaxial magnetic gear (CMG). The MGM is manufactured by injection molding a modulator cage made of a high-performance composite plastic and a thermally conductive injection molding material onto a support ring and angledly spaced modulator pole pieces. The injection molding material is preferably carbon fiber plastic or similar material. The support ring and pole pieces are made of a magnetically conductive material and are preferably single-piece castings. After injection molding, the injection molding material and the outer portion of the support ring are machined away, leaving the angledly spaced pole pieces embedded in the modulator cage, which includes the remaining molding material. The injection-molded MGM reduces costs, and the carbon fiber plastic material increases strength.

[0009] According to another aspect of the invention, an outer support ring or an inner support ring and a pole member made of a magnetically conductive material are provided. The pole member extends into the outer support ring or extends out of the inner support ring.

[0010] According to another aspect of the invention, an MGM is provided, which is constructed by injection molding a molding material onto a support ring and pole members. The outer or inner portions of the support ring and the injection molding material are machined away, leaving both the inner and outer surfaces of the exposed pole members. A modulator holder is positioned between angledly spaced magnetic pole members, thereby securing the pole members and forming the MGM.

[0011] According to another aspect of the invention, an MGM is provided, which preferably has exposed inner and outer pole member faces. The exposed pole member faces increase torque capability. However, in some embodiments, the inner or outer surface of the pole member opposite the support ring may be covered by a layer of molding material. Attached Figure Description

[0012] The above and other aspects, features, and advantages of the invention will become more apparent from the following more detailed description of the invention, taken in conjunction with the accompanying drawings, in which:

[0013] Figure 1A A first cross-sectional view of a coaxial magnetic gear (CMG) is shown.

[0014] Figure 1B A second sectional view of CMG is shown.

[0015] Figure 2 An exploded view of the CMG according to the present invention is shown.

[0016] Figure 3 The diagram shows the support ring attached to the CMG before processing according to the invention and the pole piece made of magnetic material.

[0017] Figure 4 The polar component of the CMG after the support ring is removed, according to the present invention, is shown.

[0018] Figure 5 An injection-molded modulator holder of CMG according to the invention is shown, with the modulator being molded on a support ring and a pole member made of magnetic material.

[0019] Figure 6 The diagram illustrates an electrode component embedded in the remaining injection molding material after the outer portion and support ring of the injection molding material have been removed during machining, according to the present invention.

[0020] Figure 7A A first method for manufacturing an MGM according to the present invention is shown.

[0021] Figure 7B A second method for manufacturing MGM according to the present invention is shown.

[0022] Figure 8 A second embodiment of the CMG according to the present invention is shown.

[0023] Figure 9 An exploded view of the second embodiment of the CMG according to the present invention is shown.

[0024] In several views of the accompanying drawings, corresponding reference numerals denote corresponding parts. Detailed Implementation

[0025] The following description represents the best mode conceived for carrying out the invention. This description should not be considered limiting, but merely for the purpose of describing one or more preferred embodiments of the invention. The scope of the invention should be determined with reference to the claims.

[0026] When the terms “about” or “approximately” are used in connection with elements of the invention, they are intended to describe a characteristic appearance as seen or perceived by the human eye, rather than to be a precise measurement or generally within 10% of a specified value.

[0027] Figure 1A The image shows a first sectional view of the coaxial magnetic gear (CMG) 10, and... Figure 1B The image shows a second sectional view of CMG 10.

[0028] Figure 2An exploded view of CMG 10 is shown. CMG 10 includes an output shaft 12, an output shaft bearing 14, a front gear housing 16, a modulator plate 18, a magnetic gear modulator (MGM) 40, an inner rotor 20, an inner rotor magnet 22, an outer rotor 24, an outer rotor magnet 26, a rear gear housing 28, an MGM support bearing 30, an input shaft 32, and an input shaft bearing 34. In this embodiment, the output shaft 12 is attached to rotate together with the MGM 40. Furthermore, the MGM support bearing 30 is selected to maintain the stiffness and coaxiality of the MGM 40 and to conduct heat from the MGM 40. The MGM support bearing 30 is preferably held in the CMG 10 using adhesive, a mechanical retainer, a press-fit material on the MGM support bearing 30, or a similar holding method.

[0029] The CMG 10 functions similarly to a planetary gear or planetary gear. In some embodiments, the MGM may be fixed, and in some embodiments, the inner rotor 20 may be an input and the outer rotor 24 may be an output. Those skilled in the art will recognize that various embodiments of a CMG including an MGM, as well as any CMG including an MGM constructed as described herein, are intended to fall within the scope of this invention.

[0030] Figure 3 The image shows the outer support ring 44 and the angledly spaced pole pieces 46 before processing. Figure 4 The diagram shows the pole piece 46 after the molding material and the outer portion of the outer support ring 44 have been removed, and the injection molding materials 42 and 42a between the pole pieces 46 (see [link]). Figure 5 and Figure 6 (Not shown). An outer support ring 44 is preferred, but an inner support ring or end support ring may be used instead. The support ring 44 and the pole piece 46 are made of a magnetic material, such as a ferromagnetic material, bulk magnetic glass or bulk metallic glass, laminated bulk magnetic glass, or soft magnetic composite material (SMC). The pole piece 46 preferably has a non-circular cross-section to block rotation. The preferred cross-section is hourglass-shaped, but the cross-section can be any shape that blocks rotation in the finished CMG 10. The pole piece 46 has an outer surface 46a and an inner surface 46b.

[0031] For example, the outer support ring 44 and the angledly spaced pole members 46 can be a single-piece casting machined from a single material, or a cylindrical part with the pole members attached to its inner side. Those skilled in the art will recognize that various methods of forming the support ring and attaching the angledly spaced pole members, as well as any MGM made by molding material onto the combined support ring and angledly spaced pole members, are intended to fall within the scope of this invention.

[0032] After obtaining the combined support ring and pole components, the next step in manufacturing the MGM 40 is... Figure 5 The unprocessed molded MGM 40a shown includes molding material 42 on the support ring 44 and pole member 46. Molding material 42 is preferably a high-strength thermally conductive material, such as thermally reinforced fiber-filled plastic, carbon fiber plastic, carbon fiber-filled plastic material, glass material, or high-performance composite plastic. Thermal conductivity is important because eddy currents and hysteresis losses generate heat in the MGM 40. The MGM 40 is located between the inner rotor 20 and the outer rotor 24, so heat needs to escape through the MGM base 42b and through the support bearing 30 (see [link to relevant documentation]). Figure 2 The pole piece 46 is preferably held in place during molding of the molding material 42 by being connected to the support ring 44, but may be separate and held by a fastening device. The MGM base 42b is preferably part of the molding material 42, but may be a separate piece attached to the molding material 42.

[0033] Figure 6 The image shows an MGM 40 with the excess molding material 42 and the support ring 44 covering the pole member 46 processed and removed. The MGM base 42b is retained, and the modulator holder 42a, which is part of the molding material 42, is retained, thereby holding the pole member 46.

[0034] Figure 7A A first method for manufacturing an MGM 40 is shown. The method includes forming a connected support ring and individual pole pieces at step 100, molding a high-performance composite plastic and thermally conductive injection molding material on the support ring and between the pole pieces at step 102, and machining a portion of the support ring and the molding material from the outer radius and / or inner radius at step 104 to expose the pole piece faces. In step 102, it is not necessary to mold the molding material on the support ring. In step 104, it is not necessary to machine the molding material if it does not extend radially beyond the gap between the pole pieces or axially beyond the finished dimensions of the MGM—which may include the MGM base—or is merely a layer of molding material on the pole piece face opposite the support ring. However, for efficiency, it is preferable to expose both the inner and outer surfaces of the pole pieces.

[0035] Figure 7B A second method for manufacturing the MGM 40 is shown. This method includes holding the electrode components in a fixture at step 200, molding a high-performance composite plastic and a thermally conductive injection molding material between the electrode components at step 202, and machining a portion of the molding material from the outer radius and / or the inner radius at step 204 to expose the electrode components.

[0036] Figure 8A second embodiment of the CMG 10a according to the present invention is shown, and Figure 9 An exploded view of a second embodiment of the CMG 10a is shown. The output shaft of the CMG 10a is supported by a large bearing in the front of the housing, and the output shaft is also supported by a needle roller bearing in the hollow input shaft of the motor.

[0037] Although the above description describes the MGM 40 as constructed by injection molding a modulator support retainer 42 onto the MGM pole member 46 located inside the ring 44, the MGM 40 can also be constructed by injection molding the modulator support retainer 42 under the magnetic material ring 44 and machining away the inner portion of the magnetic material ring 44, which includes the MGM pole member 46 located outside the ring 44. Furthermore, the MGM 40 can be constructed according to the invention without machining all the outer rings 44 from the MGM pole member 46. Additionally, a group of angularly spaced MGM pole members 46 can be held in place by a fixing device and a modulator support retainer 42 injection molded onto each individual MGM pole member 46.

[0038] Industrial applicability

[0039] This invention has revealed its industrial applicability in the field of magnetic gears.

[0040] Scope of the Invention

[0041] Although the invention disclosed herein has been described with reference to specific embodiments and applications, those skilled in the art can make many modifications and variations to the invention without departing from the scope of the invention as set forth in the claims. For example, the outer rotor may include an electromagnet, or the stator may reside outside the CMG providing the electric motor.

Claims

1. A method for manufacturing a magnetic gear modulator for a coaxial magnetic gear, the method comprising: A single casting forming both a support ring and angledly spaced pole components, wherein the single casting of the support ring and the angledly spaced pole components is made of a magnetically conductive material; Molding material is molded between consecutive pole pieces of the pole piece; and The support ring and a portion of the molding material are removed by machining, thereby exposing the inner and outer surfaces of the pole members and leaving the angled pole members held by a modulator support cage formed of the molding material.

2. The method according to claim 1, wherein: The support ring is an outer support ring located outside the pole component; and Removing the support ring by machining includes exposing the outer surface of the pole component.

3. The method according to claim 1, wherein: The support ring is an inner support ring located inside the pole component; and Removing the support ring by machining includes exposing the inner surface of the pole component.

4. The method according to claim 3, wherein, The molding process is injection molding.

5. The method according to claim 1, wherein: The support ring is at least one end ring; and The method includes processing to remove the at least one end ring.

6. The method according to claim 5, wherein, The molding process is injection molding.

7. The method according to claim 1, wherein, The molding material is an injection molding material.

8. The method according to claim 7, wherein, The injection molding material is a thermally conductive reinforced fiber-filled plastic.

9. The method according to claim 8, wherein, The thermally conductive reinforcing fiber-filled plastic is selected from the group consisting of thermally conductive reinforcing fiber-filled plastic, carbon fiber plastic, carbon fiber-filled plastic material, glass material, and high-performance composite plastic.

10. The method according to claim 1, wherein, The magnetic material is a ferromagnetic material.

11. The method according to claim 10, wherein, The ferromagnetic material is selected from the group consisting of bulk magnetic glass or bulk metallic glass, laminated bulk magnetic glass or soft magnetic composite material.

12. The method according to claim 1, wherein, The forming of pole components includes pole components that form non-circular cross-sections.

13. The method according to claim 12, wherein, The pole component forming a non-circular cross-section includes a pole component forming a cross-section with an hourglass shape.

14. The method according to claim 1, wherein, The pole component includes a pole component having a feature portion that blocks the rotation of the magnetic gear modulator.

15. A method for manufacturing a magnetic gear modulator for a coaxial magnetic gear, the method comprising: A single casting forming both a support ring and angledly spaced pole members, wherein the single-cast support ring and the angledly spaced pole members are made of a magnetically conductive material, wherein: The pole component has a non-circular cross-section to block the rotation of the magnetic gear modulator; Injection molding material is injected between the pole components, the injection molding material including high-performance composite plastic and thermally conductive injection molding material; The support ring and a portion of the injection molding material are removed by machining, thereby exposing the inner and outer surfaces of the pole component; The pole component remains held by a modulator support cage formed of the injection-molded material; and The coaxial magnetic gear, including the magnetic gear modulator, is assembled between the inner rotor and the outer rotor.

16. A method for manufacturing a magnetic gear modulator for a coaxial magnetic gear, the method comprising: Forming an unprocessed magnetic gear modulator includes: A single casting forming both a support ring and angledly spaced pole members, wherein the single-cast support ring and the angledly spaced pole members are made of a magnetically conductive material; and A molding material is molded between the pole components, the molding material including high-performance composite plastics and thermally conductive injection molding materials; The support ring and a portion of the molding material of the unprocessed magnetic gear modulator are removed; and The inner and outer surfaces of the electrode component are exposed, and the electrode component is held by a modulator support retainer formed of the molding material.

17. The method according to claim 16, wherein, The molding process is injection molding.

Images