Pulley decoupler

Patent metadata

Field	Value
Publication number	US-10359084-B2
Application number	US-201615549289-A
Country	US
Kind code	B2
Filing date	Mar 16, 2016
Priority date	Mar 27, 2015
Publication date	Jul 23, 2019
Grant date	Jul 23, 2019

Abstract

A decoupler is provided for rotationally driving a generator of an auxiliary-unit belt drive of an internal combustion engine, including: a pulley, a hub, and two bearing points, at which the pulley is rotatably supported on the hub, a series arrangement of a helical torsion spring and a one-way clutch, which allows the hub to overtake the pulley, and a spring plate, which is rotationally fixed in relation to the pulley or the hub, for the one spring end and a spring plate, which can be rotated in relation to the pulley and the hub, for the other spring end. The spring ends, which lie against ramp steps of the spring plates, radially expand the helical torsion spring as the driving torque is transmitted. The frictional torque, produced in one of the bearing points when the hub is overtaking, acts on the rotatable spring plate in a direction of rotation of the rotationally fixed spring plate. The other bearing point, according to the invention, has a part that is rotationally fixed in relation to the rotationally fixed spring plate, on which part the rotatable spring plate is supported, a further frictional torque thus being produced, which acts on the rotatable spring plate in the direction of rotation of the rotationally fixed spring plate.

First claim

The invention claimed is:

1. A decoupler for a rotational drive of a generator of an auxiliary unit belt drive of an internal combustion engine, the decoupler comprising:
a belt pulley adapted to be rotationally driven by a belt;
a hub that is adapted to rotationally drive a shaft of the generator arranged radially inside the belt pulley;
two axially spaced bearing points at which the belt pulley is supported for rotation on the hub;
a series arrangement radially between the belt pulley and the hub formed of a helical torsion spring and a one-way coupling that allows the hub to overtake the belt pulley in a driving rotational direction to form an overrunning hub;
a rotationally fixed spring plate that is rotationally fixed relative to the belt pulley or the hub for one end of the helical torsion spring and a rotating spring plate that rotates relative to the belt pulley and the hub for another end of the helical torsion spring;
wherein the rotationally fixed spring plate and the rotating spring plate each rise up to a step axially with a ramp shape, and spring ends of the helical torsion spring contact the ramp steps to expand the helical torsion spring radially while transferring a drive moment and a friction moment generated in one of the bearing points by the overrunning hub loads the rotating spring plate in a rotational direction of the rotationally fixed spring plate, the other bearing point has a part that is rotationally fixed relative to the rotationally fixed spring plate and on which the rotating spring plate is supported while generating another friction moment that loads the rotating spring plate in the rotational direction of the rotationally fixed spring plate,
the clamping roller overriding clutch extends axially completely outside of a belt groove in the belt pulley, and
the one bearing point is formed by a sliding bearing ring that surrounds the hub and is enclosed by an inner ring of the clamping roller overriding clutch.

2. The decoupler according to claim 1 , wherein the clamping roller overriding clutch extends axially completely outside of a belt groove in the belt pulley.

3. The decoupler according to claim 1 , wherein the rotating spring plate comprises a cylindrical sheet metal formed part that is mounted in the inner ring of the clamping roller overriding clutch.

4. The decoupler according to claim 3 , wherein the rotating spring plate comprises a spring contact part that is held in the sheet metal formed part and on which the ramp step is formed and forms a contact secured against rotation on a radially inward extending collar of the sheet metal formed part.

5. The decoupler according to claim 1 , wherein the other bearing point is a ball bearing having an inner ring that is mounted on the hub and axially supports the rotating spring plate.

6. The decoupler according to claim 5 , wherein the inner ring of the ball bearing supports the rotating spring plate by a metallic support washer and a sliding bearing washer made from plastic.

7. A decoupler for use in an internal combustion engine, the decoupler comprising:
a belt pulley;
a hub that is adapted to rotationally drive a shaft of a load arranged radially inside the belt pulley;
two axially spaced bearing points at which the belt pulley is supported for rotation on the hub;
a series arrangement radially between the belt pulley and the hub formed of a helical torsion spring and a one-way coupling that allows the hub to overtake the belt pulley in a driving rotational direction to form an overrunning hub;
a rotationally fixed spring plate that is rotationally fixed relative to the belt pulley or the hub for one end of the helical torsion spring and a rotating spring plate that rotates relative to the belt pulley and the hub for another end of the helical torsion spring;
wherein the rotationally fixed spring plate and the rotating spring plate each rise up to a step axially with a ramp-shape, and spring ends of the helical torsion spring contact the ramp steps to expand the helical torsion spring radially while transferring a drive moment and a friction moment generated in one of the bearing points by the overrunning hub loads the rotating spring plate in a rotational direction of the rotationally fixed spring plate, the other bearing point has a part that is rotationally fixed relative to the rotationally fixed spring plate and on which the rotating spring plate is supported while generating another friction moment that loads the rotating spring plate in the rotational direction of the rotationally fixed spring plate, and the one-way coupling is constructed as a clamping roller overriding clutch that is arranged radially outside of the helical torsion spring, and
the other bearing point is a ball bearing having an inner ring that is mounted on the hub and axially supports the rotating spring plate.

8. The decoupler according to claim 7 , wherein the clamping roller overriding clutch extends axially completely outside of a belt groove in the belt pulley.

9. The decoupler according to claim 7 , wherein the one bearing point is formed by a sliding bearing ring that surrounds the hub and is enclosed by an inner ring of the clamping roller overriding clutch.

10. The decoupler according to claim 9 , wherein the rotating spring plate comprises a cylindrical sheet metal formed part that is mounted in the inner ring of the clamping roller overriding clutch.

11. The decoupler according to claim 10 , wherein the rotating spring plate comprises a spring contact part that is held in the sheet metal formed part and on which the ramp step is formed and forms a contact secured against rotation on a radially inward extending collar of the sheet metal formed part.

12. The decoupler according to claim 7 , wherein the inner ring of the ball bearing supports the rotating spring plate by a metallic support washer and a sliding bearing washer made from plastic.

13. A decoupler for a belt drive, the decoupler comprising:
a belt pulley adapted to be rotationally driven by a belt;
a hub adapted to rotationally drive a shaft arranged radially inside the belt pulley;
at least two bearing points supporting the belt pulley for rotation on the hub, a first bearing point of the at least two bearing points comprising a clamping roller overriding clutch;
a helical torsion spring and a one-way coupling arranged between the belt pulley and the hub;
a fixed spring plate formed integrally with the hub and engaged with a first end of the helical torsion spring, the fixed spring plate radially surrounding the helical torsion spring and forming a sliding bearing section for the first bearing point of the at least two bearing points; and
a rotatable spring plate that rotates relative to the belt pulley and the hub, and the rotatable spring plate is engaged with a second end of the helical torsion spring.

14. The decoupler of claim 13 , wherein a second bearing point of the at least two bearing points is formed as a ball bearing assembly, and the ball bearing assembly includes an inner ring mounted on the hub that axially supports the rotating spring plate.

Assignees

• Schaeffler Technologies Ag

Inventors

• Hauck Christian

Classifications

• F16D3/12 Primary

  specially adapted for accumulation of energy to absorb shocks or vibration (by making use of fluid elements F16D3/80) · CPC title

• F16D41/06

  with intermediate wedging coupling members between an inner and an outer surface (F16D41/02, F16D41/24 take precedence) · CPC title

• F16H55/49

  Features essential to V-belts pulleys · CPC title

• F16H55/36

  Pulleys (with features essential for adjustment F16H55/52) · CPC title

• F16D3/72

  with axially-spaced attachments to the coupling parts (F16D3/56 takes precedence) · CPC title