Assembly for measuring a displacement distance produced by a braking force

Abstract

An assembly for determining a measurement quantity for a braking force acting on a brake, including a carrier and a brake holder. The aim of the invention is for the assembly to enable precise and reproducible measurements of a measurement quantity characteristic of the braking force. This aim is achieved in that the brake holder is arranged in such a way that the brake holder can be elastically and laterally displaced with respect to the carrier, wherein the brake holder is fastened to the carrier by at least one elastic bending element, wherein a sensor device is provided for determining the displacement distance of the brake holder with respect to the carrier.

Claims

1. An arrangement for determining a measurement variable for a braking force acting on a brake, comprising: a carrier, a brake holder, and a sensor device, wherein the brake holder is arranged so as to be elastically and laterally displaceable relative to the carrier, wherein the brake holder is fixed by two elastic bending elements to the carrier, wherein the sensor device determines a displacement travel of the brake holder relative to the carrier, and wherein the two elastic bending elements are led through openings in the carrier and, on a side averted from the brake holder, are fastened in support elements which are rigidly connected to the carrier.

2. The arrangement as claimed in claim 1, wherein the carrier is part of a vehicle chassis.

3. The arrangement as claimed in claim 1, wherein the at least one elastic bending element is inserted into the brake holder.

4. The arrangement as claimed in claim 1, wherein the sensor device comprises a sensorially active and a sensorially passive element, and wherein one sensor element is rigidly connected in positionally fixed fashion to the carrier or the brake holder, and the other sensor element is connected in positionally fixed fashion to the brake holder or the carrier.

5. The arrangement (30) as claimed in claim 4, wherein the sensorially active element is connected in positionally fixed fashion to the carrier and the sensorially passive element is connected in positionally fixed fashion to the brake holder.

6. The arrangement as claimed in claim 4, wherein the sensorially passive element is received in a solid measure.

7. The arrangement as claimed in claim 4, wherein the sensorially passive element is a permanent magnet, and wherein the sensorially active element is a magnetoresistive angle measuring element.

8. The arrangement as claimed in claim 4, wherein the sensorially passive element is an element composed of ferritic material, and wherein the sensorially active element is a coil arrangement.

9. The arrangement as claimed in claim 5, wherein the sensorially passive element is received in a solid measure.

10. A device for determining a measurement variable for a braking force acting on a disk brake, which is hydraulically actuatable, of a motor vehicle, comprising an arrangement as claimed in claim 1, furthermore comprising an open-loop control unit and a closed-loop control unit which is connected at the input side to the sensor device and which performs closed-loop braking control on the basis of at least one measurement signal of the sensor device.

11. A disk brake, for a motor vehicle, having an arrangement as claimed in claim 1.

12. A method for determining a measurement variable for a braking force acting on a hydraulically actuatable disk brake of a motor vehicle, having an arrangement as claimed in claim 1, wherein a lateral displacement of the brake holder relative to the carrier is measured.

13. An arrangement for determining a measurement variable for a braking force acting on a brake, comprising: a carrier, a brake holder, and a sensor device, wherein the brake holder is arranged so as to be elastically and laterally displaceable relative to the carrier, wherein the brake holder is fixed by at least one elastic bending element to the carrier, wherein the sensor device determines a displacement travel of the brake holder relative to the carrier, and wherein the at least one elastic bending element is in each case laterally surrounded by a space into which the at least one elastic binding element is configured to expand in the event of a lateral displacement of the brake holder relative to the carrier.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) An exemplary embodiment of the invention will be discussed in more detail on the basis of a drawing. In the drawing, the single FIGURE shows, in a highly schematic illustration, a preferred embodiment of an arrangement for determining a displacement travel generated by braking force.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(2) The arrangement 30 comprises a carrier 1, which is preferably a part of the positionally fixed vehicle running gear or vehicle chassis. A brake holder 2 is designed for a disk brake with a floating caliper. The brake holder 2 is fastened in elastically displaceable fashion to the carrier 1. Here, the brake holder 2 is elastically displaceable relative to the carrier 1 in a lateral direction.

(3) The brake holder 2 and its fastening components contain the major part of the mechanism for measuring a displacement travel x under the influence of a braking force F.sub.U. The brake holder 2 preferably comprises the mechanical entirety of a floating-caliper brake, which generates the braking force F.sub.U by means of brake piston, brake fist, brake pads and a brake disk.

(4) The brake holder 2 bears via abutment elements 3a, 3b, which are preferably formed as flanges, against the carrier 1. The brake holder 2 is screwed via bending elements 4a, 4b, which in the present exemplary embodiment are formed as bolts, to the carrier 1. The nuts 5a, 5b and the support elements 6a, 6b serve for this purpose. The casing-like support elements 6a, 6b are recessed in positively locking fashion into the carrier 1 or the chassis in in each case one recess 7 in the carrier, and also surround the bolts with a form fit in the region 8, whereas said support elements, in each case in the region 9, provide play, in particular lateral play, for the bending elements 4a, 4b. Between the two abutment elements 3a, 3b and the carrier 1, there are arranged intermediate elements 10 which allow the abutment elements 3a, 3b to slide on the carrier 1, or the material of which can deform elastically under the action of a shear force.

(5) As can be seen from the FIGURE, the bending elements 4a, 4b surround a cavity 11, which is formed in particular as a ring-shaped space, and which is arranged in particular between the abutment element side or flange side and the screw connection thereof, in which the bending elements 4a, 4b can bend under the influence of a force F.sub.U, as is symbolically illustrated here by the reference designation 12. Said bending results in a displacement travel x of the brake holder 2 relative to the carrier 1.

(6) To measure the displacement travel x, a sensor device 36 is provided. The sensor device 36 comprises a sensor 13 which is mounted in positionally fixed fashion on the carrier 1 and which interacts with a solid measure 14 which, in a cavity 22 formed between carrier 1 and brake holder 2, is situated opposite a bore 24 in the carrier 1. The solid measure 14 is mounted positionally fixedly on the brake holder 2 and thus replicates the displacement travel x. The sensor 13 comprises a sensorially active element 15, and the solid measure 14 comprises a sensorially passive element 16. An air gap 26 exists between sensor 13 and solid measure 14, and a field coupling exists between the active and passive sensorial elements. With regard to the practical realization of the sensor arrangement, it should be ensured that the method used permits adequately high spatial resolution.

(7) In a first preferred embodiment, a magnetostatic method is used, utilizing a permanent magnet as a sensorially passive element for the detection of the displacement travel x. In this first preferred variant, as a sensorially active element, a magnetoresistive angle measuring element is used which measures the rotation, associated with the displacement x, of the vector direction of the permanent magnetic field. In a second preferred variant, a Hall arrangement is used as a sensorially active element for measuring the magnetic spatial amplitude and the displacement thereof as a function of x.

(8) In a second preferred embodiment, a magnetodynamic method using ferritic material as a sensorially passive element is used. A coil arrangement with corresponding electronic circuitry is in this case used as a sensorially active element for measuring the change, associated with x, of the inductive coupling to the sensorially passive element.

(9) The configuration shown in the FIGURE is merely a schematic illustration of a preferred embodiment of the arrangement proposed. In the embodiment shown, the bending elements 4a, 4b are separate components that are inserted into the holder 2. The bending elements 4a, 4b may alternatively also be formed in one piece with the brake holder 2.

(10) In the preferred embodiment shown in the FIGURE, the intermediate elements 10 are caps. A sliding or deformation layer may for example also be laid into the abutment elements 3a, 3b or flanges. The material of said layer may be a suitable elastic plastic, or a material that is known from plain bearings.