Electromagnetic brake assembly

• US 4,049,089 A
• Filed: 07/06/1976
• Issued: 09/20/1977
• Est. Priority Date: 07/06/1976
• Status: Expired due to Term

• Current Assignee: SN Operating Company Incorporated
• Original Assignee: Shepard Niles Crane & Hoist Corporation
• Inventors: Rundle, Frederick Stanley
• Primary Examiner(s): Reger, Duane A.
• Application Number:
  US05/702,420
• Time in Patent Office: 441 Days
• Field of Search: 188/71.8, 188/71.9, 188/170, 188/171, 192/111 B
• US Class Current: 188/171
• CPC Class Codes: F16D 2055/0058 Fully lined, i.e. braking surface extending over the entire disc circumference
• CPC Class Codes: F16D 2121/22 for releasing a normally applied brake
• CPC Class Codes: F16D 55/28 Brakes with only one rotating disc
• CPC Class Codes: F16D 59/02 spring-loaded and adapted to be released by mechanical, fluid, or electromagnetic means
• CPC Class Codes: F16D 65/46 with screw-thread and nut
• CPC Class Codes: F16D 65/847 with open cooling system, e.g. cooled by air

Abstract

An electromagnetic brake assembly is provided for adjusting the axial distance or gap between the brake wheel and pressure plate assembly during rotation of the brake wheel, without increasing the force exerted by the pressure plate assembly on the brake wheel or varying the force exerted by the electromagnetic means on the pressure plate assembly. Preferably, the pressure plate assembly is comprised of a pressure ring for engaging a brake liner on movement of the pressure plate assembly toward the brake wheel, and a brake armature for engaging an electromagnetic means on movement of the pressure plate assembly away from the brake wheel. Such gap control means is in turn comprised of means for selectively moving the pressure ring relative to the brake armature, most desirably by rotating the pressure ring and brake armature relative to each other. Preferably, the brake assembly also has cooling means for channelling air through passageways adjacent the brake liner, preferably by power provided by the drive shaft to be braked and most desirably by stator means adjacent the periphery of the brake wheel forcing said air through said passageways adjacent the brake liner.

Claims

1. An electromagnetic brake assembly comprising:

A. a rotatable brake wheel fixed to a shaft which has the rotation thereof selectively braked by the brake assembly;

B. a pressure ring nonrotatably mounted axially a given distance from said brake wheel during operational rotation of said shaft and adapted to axially move toward and away from the brake wheel;

C. a brake armature mounted axially from said pressure ring and adapted to axially move in fixed relation with respect to said pressure ring during operational rotation of said shaft;

D. at least one brake liner adapted to fricationally engage between the brake wheel and pressure ring when the pressure ring is moved axially toward the brake wheel;

E. an electromagnetic means mounted axially from the brake armature for engaging the brake armature to move the pressure ring away from the brake wheel;

F. biasing means for urging the brake armature and pressure ring toward the brake wheel to engage the brake liner between the brake wheel and pressure ring and brake the rotation of the brake wheel; and

G. gap control means for adjusting the axial distance between the brake wheel and the pressure ring.

2. An electromagnetic brake assembly as set forth in claim 1 wherein:

said gap control means comprises means for selectively moving the pressure ring relative to the brake armature.

3. An electromagnetic brake assembly as set forth in claim 2 wherein:

said gap control means comprises means for rotating the pressure ring and the brake armature relative to each other, and retainer means for preventing relative rotation of the pressure ring and brake armature during operation of the brake assembly.

4. An electromagnetic brake assembly as set forth in claim 1 comprising in addition:

an indicator means for monitoring said given distance between the brake wheel and pressure ring during operational rotation of the shaft to determine need for readjustment by the gap control means.

5. G. cooling means for channelling air through passageways that include openings through the brake wheel, said openings being adjacent to the brake liner.

6. An electromagnetic brake assembly as set forth in claim 5 wherein:

said cooling means is provided by rotation of the shaft during operation.

7. An electromagnetic brake assembly as set forth in claim 6 wherein:

said cooling means comprises stator means adjacent the periphery of the brake wheel for forcing said air through said passageway adjacent the brake liner.

8. An electromagnetic brake assembly comprising:

A. a rotatable brake wheel fixed to a shaft which has the rotation thereof selectively braked by the brake assembly;

B. a pressure ring nonrotatably mounted, axially a given distance from said brake wheel during operational rotation of said shaft and adapted to axially move toward and away from the brake wheel;

C. a brake armature mounted axially from said pressure ring and adapted to axially move in fixed relation with respect to said pressure ring during operational rotations of said shaft;

D. at least one brake liner adapted to frictionally engage between said brake wheel and pressure ring when the pressure ring is moved axially toward the brake wheel;

E. a mechanical bias means for urging the brake armature and pressure ring toward the brake wheel to engage the brake liner between the brake wheel and pressure ring and brake the rotation of the brake wheel;

F. an electromagnetic means mounted axially from the brake armature for selectively engaging the brake armature to urge the pressure ring away from the brake wheel against the bias means; and

G. a means for adjusting the axial distance between the brake wheel and the pressure ring.

9. An electromagnetic brake assembly as set forth in claim 8 wherein:

said gap control means comprises means for selectively moving the pressure ring relative to the brake armature.

10. An electromagnetic brake assembly as set forth in claim 9 wherein:

said gap control means comprises means for rotating the pressure ring and the brake armature relative to each other, and retainer means for preventing relative rotation of the pressure ring and brake armature during operation of the brake assembly.

11. An electromagnetic brake assembly as set forth in claim 8 comprising in addition:

an indicator means for monitoring said given distance between the brake wheel and pressure plate assembly during operational rotation of the shaft to determine need for readjustment by the gap control means.

12. An electromagnetic brake assembly as set forth in claim 8 comprising in addition:

G. cooling means for channelling air through passageways that include openings through the brake wheel, said openings being adjacent to the brake liner.

13. An electromagnetic brake assembly as set forth in claim 12 wherein:

said cooling means is provided by rotation of the shaft during operation.

14. An electromagnetic brake assembly as set forth in claim 13 wherein:

said cooling means comprises stator means adjacent the periphery of the brake wheel for forcing said air through said passageway adjacent the brake liner.

15. An electromagnetic brake assembly comprising:

A. a rotatable brake wheel fixed to a shaft which has the rotation thereof selectively braked by the brake assembly;

B. a pressure ring nonrotatably mounted axially a given distance from said brake wheel during operational rotation of said shaft and adapted to axially move toward and away from the brake wheel;

C. a brake armature mounted axially from said pressure ring and adapted to axially move in fixed relation with respect to said pressure ring during operational rotation of said shaft;

D. at least one brake liner adapted to frictionally engage between the brake wheel and pressure ring when the pressure ring is moved axially toward the brake wheel;

E. an electromagnetic means mounted axially from the brake armature for engaging the brake armature to move the pressure ring away from the brake wheel;

F. biasing means for urging the brake armature and pressure ring toward the brake wheel to engage the brake liner between the brake wheel and pressure ring and brake the rotation of the brake wheel; and

G. cooling means for channelling air through passageways that include openings through the brake wheel, said openings being adjacent to the brake liner.

16. An electromagnetic brake assembly as set forth in claim 15 wherein:

said cooling means is provided by rotation of the shaft during operation.

17. An electromagnetic brake assembly as set forth in claim 16 wherein:

said cooling means comprises stator means adjacent the periphery of the brake wheel for forcing said air through said passageway adjacent the brake liner.