Electromagnetic clutch brake assembly

• US 3,893,191 A
• Filed: 03/14/1974
• Issued: 07/01/1975
• Est. Priority Date: 03/14/1974
• Status: Expired due to Term

• Current Assignee: Edward Kim-Eng, Joseph Gold, Paul Emile Plante
• Original Assignee: Edward Kim-Eng, Joseph Gold, Paul Emile Plante
• Inventors: Gold, Joseph, Kim-Eng, Edward, Plante, Paul Emile
• Primary Examiner(s): Skudy, R.
• Application Number:
  US05/451,304
• Time in Patent Office: 474 Days
• Field of Search: 310/76,94,75,93,77,95,78,108,92,110,100,96,105,79 192/3.5E,12D,18B,1A,110 318/362,365-371
• US Class Current: 310/76
• 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 67/06 electromagnetically actuated

Abstract

A rotary electromagnetic clutch brake assembly having opposed spring and magnetic forces such that on activation the clutch engages momentarily before the brake releases and on deactivation the brake engages before the clutch disengages so as to assure precise positive control of the rotary output of the assembly.

Claims

1. Electromagnetic clutch brake assembly comprising:

a. clutch armature having a frictional engaging face which is movable between an engaged power-transmitting position and a disengaged no-power position, b. clutch biasing means contacting said clutch armature for biasing said clutch face to its disengaged position, c. rotor positioned adjacent said armature and having a frictional engaging face positioned to be engaged and driven by said clutch armature face when said clutch face is in its engaged position, d. said clutch biasing means comprising spider means having a plurality of spring arms, means connecting said arms to said armature, and means positioning said spider a predetermined distance from said rotor, e. brake armature positioned adjacent to said rotor and having a frictional engaging face movable between an engaged braking position and a disengaged free position, f. brake biasing means contacting said brake armature for biasing said brake face to its engaged braking position, g. brake stop means positioned adjacent said brake face and having a fixed frictional Engaging face positioned to engage and stop said brake face when said brake face is in its engaged position, h. electromagnetic coil associated with said rotor for magnetically displacing said clutch face against the opposing force of said clutch biasing means toward and in engagement with said rotor means and magnetically displacing said brake face against the opposing force of said brake biasing means away from and out of engagement with said stop means in response to the activation of said coil, i. said clutch and brake biasing means having biasing forces relative to each other and to the magnetic forces required to engage and disengage said clutch and brake faces such that clutch means engages before said brake means disengages on activation of said coil, and said brake means engages before said clutch means disengages on deactivation of said coil.

2. An electromagnetic clutch brake assembly as claimed in claim 1 wherein the relative stiffness of the springs for said clutch and brake biasing means is such that on activation of the assembly the clutch biasing means yields to the magnetic force tending to engage the clutch armature to the rotor, and the spring force acting on the brake biasing means prevents said brake armature from disengaging from said brake stop means until the clutch armature engages the rotor, thereby increasing the magnetic force acting on the brake armature an amount sufficient to overcome the force of said brake biasing means so as to disengage said brake armature from the brake stop means.

3. In a rotary electromagnetic clutch brake assembly having a clutch armature with a frictional engaging face rotatably mounted about on a central axis, a rotor on said axis with a corresponding clutch engaging face, a brake armature also rotatably mounted on said axis with a brake face, and a brake stop means with a corresponding brake face, and a coil for engaging said clutch face to said rotor face and for disengaging said brake face from said stop means upon activation of said coil, the improvement comprising a first biasing means fixed laterally with respect to said axis for urging said clutch face away from engagement with said rotor, and a second biasing means for urging said brake face into engagement with said brake stop means, the relative biasing forces of said first and second biasing means being predetermined such that said first biasing means releases the clutch face to engage the rotor before the second biasing means release the brake face from the brake stop means, said first biasing means comprising a spider means mounted on said axis having a central position fixed laterally relative to said axis, laterally displaceable spring arms radiating therefrom, and means connecting said arms to the clutch armature.

4. The improvement as claimed in claim 3 further comprising a plurality of radially extending slots in the clutch armature face.

5. An electromagnetic clutch brake assembly for transmitting and braking power from a rotary input to a rotary output comprising:

a. rotary clutch means comprising an armature driven on a given axis by said rotary input, said armature having a frictional clutch face, and spider means connecting said armature and clutch face to said rotary input, said armature and clutch face being mounted on said spider means so as to be laterally displaceable between an engaged power transmitting and disengaged idling position, said spider means biasing such face toward its disengaged position;

b. rotor means mounted coaxial and adjacent to said clutch armature, said rotor means having at one end magnetic pole rings positioned so as to be contacted and driven by said clutch face when such face is in its engaged position;

c. brake means mounted adjacent said rotor means comprising a brake armature and brake frictional face, means for mounting said brake armature and face adjacent each other and coaxial with and laterally displaceable relative to said rotor between an engaged braking position and A disengaged free position, said brake armature and face mounting means comprising a spline laterally displaceably connecting said face to said rotor means, for rotating said face with said rotor, biasing means for urging said brake face to its engaged braked position, brake stop means comprising a fixed frictional face positioned to be contacted by and to stop said brake face when said brake face is in its engaged position, d. circular shell fixedly mounted coaxially with said rotor, said shell including an electromagnetic coil for generating a magnetic field through said rotor pole rings, clutch armature, shell, and brake armature for magnetically displacing the clutch face to engage the rotor pole rings and for magnetically displacing said brake armature and brake face from said stop means in response to the activation of said coil, reversing this when said coil is deactivated, e. said clutch spider and brake biasing means having stiffnesses relative to each other and relative to the magnetic forces required to displace said clutch and brake faces such that said clutch face engages before said brake face disengages on activation of said coil, and said brake face engages before said clutch face disengages on deactivation of said coil.

6. An assembly as claimed in claim 5 wherein said mounting means further comprises dowel means laterally displaceably mounting said brake armature to said rotor means.

7. An assembly as claimed in claim 6 wherein said brake biasing means comprise a plurality spring coaxially positioned for urging said brake armature and face toward said brake stop means.

8. An assembly as claimed in claim 7 further comprising means for adjusting the position of the brake stop means to compensate for wear of the brake face.

9. An assembly as claimed in claim 5 wherein said rotor means further comprises arcuate slots between said pole rings.

10. An assembly as claimed in claim 5 wherein said shell further comprises arcuate slots adjacent said brake armature for directing the magnetic field to and through said brake armature.

11. An assembly as claimed in claim 5 wherein said clutch face further comprises a plurality of radially extending slots.