ELASTIC ENCODER AND MANUFACTURING METHOD THEREOF

• US 20200132518A1
• Filed: 10/30/2018
• Published: 04/30/2020
• Est. Priority Date: 10/30/2018
• Status: Active Grant

• Current Assignee: STM Corp. (Jung-Hyun Oh)
• Original Assignee: STM Corp. (Jung-Hyun Oh)
• Inventors: KIM, Jun Woo, KIM, Se Hoon, CHO, Su Won
• Granted Patent: US 11,092,467 B2
• Time in Patent Office: Days
• CPC Class Codes: B29C 48/0011 combined with compression moulding
• CPC Class Codes: B29C 48/0021 combined with joining, lining or laminating
• CPC Class Codes: B29C 48/0022 combined with cutting
• CPC Class Codes: B29C 48/022 characterised by the choice of material
• CPC Class Codes: B29C 48/06 Rod-shaped
• CPC Class Codes: B29K 2021/006 Thermosetting elastomers
• CPC Class Codes: B29K 2995/0008 Magnetic or paramagnetic
• CPC Class Codes: B29L 2031/7096 Rings or ring-like articles
• CPC Class Codes: G01D 11/245 Housings for sensors
• CPC Class Codes: G01D 2205/80 Manufacturing details of magnetic targets for magnetic encoders
• CPC Class Codes: G01D 5/245 using a variable number of pulses in a train
• CPC Class Codes: G01D 5/2451 Incremental encoders G01D5/2454 takes precedence
• CPC Class Codes: H01F 1/083 in a bonding agent
• CPC Class Codes: H01F 1/42 of organic or organo-metallic materials , e.g. grapheneH01F1/44 takes precedence
• CPC Class Codes: H01F 41/00 Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
• CPC Class Codes: H01F 7/0215 Flexible forms, sheets
• CPC Class Codes: H01F 7/0294 Detection, inspection, magnetic treatment

Abstract

Disclosed herein are an elastic encoder and manufacturing method thereof. The elastic encoder of the present invention includes a reinforcing rim which has a reinforcing body and a reinforcing flange formed along a peripheral part of the reinforcing body and which is manufactured using a metallic material; and a plastic magnet which is bound to the reinforcing flange so as to surround the reinforcing flange, includes synthetic resin, rubber material, and magnetic powder, and has a plurality of magnetic poles magnetized in a circumferential direction.

Claims

1. An elastic encoder comprising;

a reinforcing rim which has a reinforcing body and a reinforcing flange formed along a peripheral part of the reinforcing body and which is manufactured using a metallic material; and

a plastic magnet which is bound to the reinforcing flange so as to surround the reinforcing flange, includes synthetic resin, rubber material, and magnetic powder, and has a plurality of magnetic poles magnetized in a circumferential direction.

2. The elastic encoder of claim 1, wherein:

the reinforcing body is formed in an annular shape; and

the reinforcing flange extends in a radial direction from an outer surface of the reinforcing body and is formed in an annular shape so as to be concentric with the reinforcing body.

3. The elastic encoder of claim 2, wherein:

the plastic magnet is bound to one surface and a corner part of the reinforcing flange; and

the corner part of the reinforcing flange is buried in the plastic magnet.

4. The elastic encoder of claim 3, wherein the plastic magnet includes:

one surface binding part bound to one surface of the reinforcing flange;

a corner binding part which extends from the one surface binding part and is bound to a corner part of the reinforcing flange; and

an other surface binding part which extends from the corner binding part toward the reinforcing body so that the corner part of the reinforcing flange is buried therein.

5. The elastic encoder of claim 4, wherein:

an inclined surface part is formed at an outer surface of the other surface binding part so that a width of the inclined surface part progressively narrows toward an end of the other surface binding part; and

an adhering part, whose thickness progressively decreases toward the reinforcing body, is formed at an inner surface of the other surface binding part so that the adhering part is adhered to the other surface of the reinforcing flange.

6. The elastic encoder of claim 1, wherein the plastic magnet is formed by extruding a plastic ring, cutting the extruded plastic ring to a circumferential length of the reinforcing rim, binding ends of the cut plastic ring to form an annular shape, placing the annular plastic ring at an upper side of the reinforcing flange, and pressing the annular plastic ring using a mold to bind the annular plastic ring to the reinforcing flange.

7. The elastic encoder of claim 1, wherein a plurality of magnetic poles are magnetized in the plastic magnet due magnetic field anisotropy.

8. The elastic encoder of claim 1, wherein a plurality of magnetic poles are magnetized in the plastic magnet due to mechanical anisotropy.

9. The elastic encoder of claim 1, wherein the rubber material includes one or more of natural rubber (NR), nitrile butadiene rubber (NBR), styrene butadiene rubber (SBR), ethylene propylene diene monomer (EPDM), acrylic rubber (ACM), acrylic ethylene rubber (AEM), ethylene propylene rubber (EPM), fluorocarbon rubber (FPM), fluoro rubber (FKM), vinyl methyl silicone rubber (VMQ), epichlorohydrin rubber (ECO), polyester urethane (PU), hydrogenated nitrile butadiene rubber (HNBR), chloroprene rubber (CR), and chloro sulfonated polyethylene rubber (CSM).

10. A method of manufacturing an elastic encoder, the method comprising:

mixing synthetic resin, rubber material, and magnetic powder;

extruding a plastic threaded rod using an extruding device;

cutting the plastic threaded rod in a circumferential length of a reinforcing rim;

forming a plastic ring by binding ends of the cut plastic threaded rod;

curing and forming the plastic ring and the reinforcing rim using a mold; and

forming a plastic magnet by magnetizing the plastic ring cured and formed in the reinforcing rim.

11. The method of claim 10, wherein a corner part of the reinforcing flange of the reinforcing rim is buried in the plastic magnet.

12. The method of claim 11, wherein the plastic magnet includes:

one surface binding part bound to one surface of the reinforcing flange;

a corner binding part which extends from the one surface binding part and is bound to a corner part of the reinforcing flange; and

an other surface binding part which extends from the corner binding part toward the reinforcing body so that the corner part of the reinforcing flange is buried therein.

13. The method of claim 12, wherein:

an inclined surface part is formed at an outer surface of the other surface binding part so that a width of the inclined surface part progressively narrows toward an end of the other surface binding part; and

an adhering part, whose thickness progressively decreases toward the reinforcing body, is formed at an inner surface of the other surface binding part so that the adhering part is adhered to the other surface of the reinforcing flange.

14. The method of claim 10, wherein a plurality of magnetic poles are magnetized in the plastic magnet due magnetic field anisotropy.

15. The method of claim 10, wherein a plurality of magnetic poles are magnetized in the plastic magnet due to mechanical anisotropy.