Torque limiter arrangement for rotating device

• US 5,190,499 A
• Filed: 10/02/1990
• Issued: 03/02/1993
• Est. Priority Date: 10/02/1989
• Status: Expired due to Fees

• Current Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Inventors: Kogita, Hidekazu, Mori, Keiji
• Primary Examiner(s): Stodola, Daniel P.
• Application Number:
  US07/591,640
• Time in Patent Office: 882 Days
• Field of Search: 464/36, 464/30, 464/35, 464/37, 464/38, 464/41, 192/56 R, 192/48.1, 192/48.7, 350/636, 350/637, 350/632, 350/604, 350/605, 248/548, 248/549, 248/900
• US Class Current: 464/36
• CPC Class Codes: B60R 1/074 for retracting the mirror arrangements to a non-use position alongside the vehicle
• CPC Class Codes: F16D 7/08 moving axially between engagement and disengagement

Abstract

A torque limiter arrangement is used for a rotating device like a door mirror. The arrangement controls relative rotation between a fixed element and a rotational element which are drivingly connected by a drive unit. That is, a first clutch is released when a relative torque not less than a fixed first torque is effected between the fixed element and the rotational element. A second clutch is released when a relative torque not less than a fixed second torque is applied between the fixed element and the rotational element. A first spring is operatively connected with the first clutch to determine the first torque. A second spring is operatively connected with the second clutch to determine the second torque.

Claims

1. A torque limiter arrangement, for a rotating device, adapted to control relative rotation between a fixed element and a rotational element operatively connected to a drive unit, comprising:

a first clutch disposed between said fixed element and said rotational element and releasable upon application of a relative torque not less than a predetermined first torque between the fixed element and the rotational element;

a second clutch disposed between said fixed element and said rotational element and releasable upon application of a relative torque not less than a predetermined second torque between the fixed element and the rotational element;

a first biasing means operatively connected with the first clutch to determine the first torque; and

a second biasing means operatively connected with the second clutch to determine the second torque;

wherein the second biasing means provides a biasing force greater than a biasing force provided by the first biasing means to such a degree that the second torque is always larger than the first torque,

wherein said first and second biasing means include at least one first spring operatively connected between and acting on the first and second clutches, and at least one second spring operatively connected with and acting only on the second clutch, and

wherein said first biasing means is comprised solely of said at least one first spring acting on said first clutch and said second biasing means is comprised of said at least one first spring and said at least one second spring acting together on said second clutch.

2. A torque limiter arrangement according to claim 1, in which:

the first clutch includes a regulating plate having first pockets and fixed on a shaft secured on the fixed element, and fire balls engageable with the first pockets;

the second clutch includes a base plate having second pockets and fixed on the shaft, and second balls engageable with the second pocket;

a plurality of first springs interposed between the first and second balls for applying force to said first and second balls; and

a plurality of second springs interposed between said rotation member and the second balls for applying a force to the second balls.

3. A torque limiter arrangement according to claim 2, in which the rotational element has a plurality of through holes each accommodating therein each first spring, respectively.

4. A torque limiter arrangement according to claim 3, in which the rotational element has a plurality of blind holes each accommodating therein each second spring, respectively.

5. A torque limiter arrangement according to claim 4, in which the rotational element has a reinforcing rib located outwardly of the through holes and the blind holes.

6. A torque limiter arrangement according to claim 4, in which the first and second springs are coil springs, and the torque limiter arrangement further comprises a spring holder interposed between the rotational element and the second clutch, the spring holder including insertion legs each inserted into each first coil spring in each through hole and urging pieces each engaging each second spring.

7. A rotating device comprising:

a stay having a shaft thereon;

a first clutch including a regulating plate fixed on a base end of the shaft and having at least three first pockets arranged in a circumferential direction of the shaft, and first balls engageable with the first pockets;

a second clutch including a base plate fixed on a free end of the shaft and having at least three second pockets arranged in the circumferential direction of the shaft, and second balls engageable with the second pockets;

a frame having a boss attached rotatably to the shaft between the first and second clutches;

the boss having at least three through holes extending along an axis of the shaft so as to correspond to the first pockets, and at least three blind holes extending along the axis of the shaft with a closed end of each blind hole disposed adjacent to the base end of the shaft;

first springs each inserted into a respective through hole to urge the first ball toward the regulating plate as well as to urge the second ball toward the base plate; and

second springs each accommodated in a respective blind hole to urge the second ball toward the base plate;

wherein a biasing force of the second springs is set at such a value that a combined biasing force of the first and second springs is larger than a biasing force of the first springs so that a release torque of the second clutch is always larger than a release torque of the first clutch.