Actuator for a functional unit of a motor vehicle

Patent metadata

Field	Value
Publication number	US-9841074-B2
Application number	US-201514658665-A
Country	US
Kind code	B2
Filing date	Mar 16, 2015
Priority date	Sep 14, 2012
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

An actuator for a motor vehicle functional unit includes a force transmission unit transmitting an actuating force to an actuating member and being displaced by a measuring travel in a force transmission direction. A force measurement device detects an actual value of the actuating force and includes a spring acting in the force transmission direction, having resilient action counter to which the force transmission unit is displaced and being tensioned by the actuating force over a resilient excursion, a micro switch having smaller switching travel than the measuring travel and being actuated upon displacement of the force transmission unit if the actuating force reaches the actual value, and a stop element for actuating the switch. The switch or element are coupled to or fixed relative to the force transmission unit and the switch and/or element are resiliently supported to compensate for a difference between the switching and measuring travels.

First claim

The invention claimed is:

1. An actuator for a functional unit of a motor vehicle, the actuator comprising:
a drive unit producing an actuating force;
an actuating member;
a force transmission unit configured to transmit said actuating force to said actuating member, said force transmission unit being supported so as to be displaceable by a measuring travel in a force transmission direction; and
a force measurement device configured to detect a first actual value and a second actuating value of said actuating force, said force measurement device including:
a first spring acting in said force transmission direction and having a resilient action counter to which said force transmission unit can be displaced, said first spring configured to be tensioned under action of said actuating force over a first resilient excursion;
a first micro switch having a switching travel being smaller than said measuring travel of said force transmission unit and being actuated upon a displacement of said force transmission unit over said first resilient excursion if said actuating force reaches said first actual value to detect said first actual value;
a first stop element configured to actuate said first micro switch;
said first micro switch or said first stop element being coupled to said force transmission unit, said first stop element or said first micro switch being fixed in position relative to said force transmission unit, and at least one of said first micro switch or said first stop element being resiliently supported to compensate for a difference between said switching travel of said micro switch and said measuring travel of said force transmission unit;
a second spring disposed in series with said first spring, said second spring being pretensioned by a pretensioning force exceeding said first actual value of said actuating force, said second spring being configured to be tensioned over a second resilient excursion by an action of said actuating force if said actuating force exceeds said pretensioning force;
a second micro switch being actuated to detect said second actual value corresponding to a displacement of said force transmission unit over said second resilient excursion upon said force transmission unit being displaced over said second resilient excursion;
said first micro switch providing a signal being used directly to switch off said drive unit upon said first actual value being reached; and
said second micro switch providing a switching signal setting out a switch-off criterion for said drive unit upon said second actual value being reached to prevent an overload.

2. The actuator according to claim 1 , wherein said first stop element is a first sensor pin being resiliently supported and pretensioned with a sensor pin pretensioning force being higher than said actuating force of said first micro switch.

3. The actuator according to claim 1 , wherein said force measurement device has a second stop element to actuate said second micro switch, said second micro switch or said second stop element is coupled to said force transmission unit, and said second stop element or said second micro switch is fixed in position relative to said force transmission unit.

4. The actuator according to claim 3 , wherein said second stop element is a second sensor pin being resiliently supported and pretensioned with a sensor pin pretensioning force being greater than an actuating force of said second micro switch to compensate for a difference between a switching travel of said second micro switch and said measuring travel of said force transmission unit.

5. The actuator according to claim 1 , wherein said switching travel of said first micro switch and said second micro switch is orientated parallel to said force transmission direction, and at least one of said first micro switch and said second micro switch or said first stop element and said second stop element are disposed offset relative to each other along said force transmission direction.

6. The actuator according to claim 1 , which further comprises a housing on which said actual value of said actuating force is indicated.

7. The actuator according to claim 6 , wherein said actual value of said actuating force is marked on said housing in the form of a machine-readable encoding.

8. The actuator according to claim 7 , wherein said machine-readable encoding is a bar code.

Assignees

• Brose Fahrzeugteile

Inventors

• Roos Stephan

Classifications

• F16D2066/005

  Force, torque, stress or strain · CPC title

• B60T13/746

  and mechanical transmission of the braking action · CPC title

• B60T7/085 Primary

  by electrical means, e.g. travel, force sensors · CPC title

• B60T7/107

  with electrical power assistance · CPC title

• F16D66/00 Primary

  Arrangements for monitoring working conditions, e.g. wear, temperature · CPC title