BRAKE-FORCE-SENSING DEVICE FOR VEHICLE RUNNING GEARS

Abstract

In a measuring device for the measurement of the brake torque on an aircraft landing gear, a connecting element that is transversally loaded by said brake torque is provided with measuring elements which produce a measuring signal in function of a deformation of said connecting element. In one of two preferred variants, said measuring elements are attached to the surface of a cavity in said connecting element, and in the second preferred embodiment, a corresponding sensor is introduced into said connecting element as a whole, said sensor being so designed that deformations affect its enclosure and deform the latter as well.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention shall be explained in more detail by means of preferred exemplary embodiments and with reference to figures.

FIG. 1 schematic illustration of an aircraft landing gear (bogie);

FIG. 2 longitudinal section of a bolt with a first embodiment of the measuring device;

FIG. 3 longitudinal section in analogy to FIG. 2 of a second embodiment of the invention;

FIG. 4 cross-section according to IV-IV in FIG. 3 in unstressed condition; and

FIG. 5 cross-section as in FIG. 4 in stressed condition.

Claims

1. Device for measuring the brake torque in a vehicle undercarriage in which the brake torque is transmitted to said vehicle undercarriage by a bar-shaped member, said bar-shaped member being loaded transversally by said brake torque, and measuring means being provided which are operatively connected mechanically to said bar-shaped member, said measuring means allowing a measurement of the strain or contraction of said bar-shaped member that is caused by said transversal load, wherein said bar-shaped member is essentially hollow and said measuring means are located in the interior of said bar-shaped member.

2. The device of claim 1, wherein said bar-shaped member is a hollow bolt that connects a torque takeout arm which serves for transmitting said brake torque from the brake to said undercarriage, to said undercarriage of said vehicle or to the stationary part of the brake assembly.

3. The device of claim 1, wherein said measuring means are arranged at a surface of said bar-shaped member.

4. The device of claim 3, wherein said measuring means are arranged in pairs, the two parts of each pair being arranged such that they measure variations of the surface that are oriented in opposite directions.

5. The device of claim 1, wherein said measuring means are located in an enclosure of a sensor that extends into a cavity of said bar-shaped member, at least a part of said enclosure being mechanically operatively connected to said bar-shaped member and said measuring means being mechanically operatively connected to said enclosure part such that a deformation of said bar-shaped member is transmittable via said enclosure part to said measuring means.

6. The device of claim 5, wherein said measuring means are arranged such that they generate a signal upon variation of the curvature of said enclosure of said sensor.

7. The device of claim 1, wherein said measuring means are strain gauges.

8. The device of claim 1, wherein said measuring means detect an elongation in a measuring direction and at least two of them at a time are mutually aligned with their measuring directions such that the signals of said measuring means are additively or subtractively combinable into respective total signals, the total signal that may result from the transversal load during a brake application being greater than that of the individual measuring means while the total signal that may result from other transversal loads is a smaller signal than that of an individual measuring means.

9. The device of claim 8, wherein the measuring directions of two of said measuring means are arranged at an angle of essentially 90°.

10. A sensor for use in the device of claim 5, wherein the sensor comprises an enclosure on whose internal surface measuring means are arranged and/or which is internally provided with at least one support that connects points of the enclosure that are spaced apart, at least one measuring means being arranged on said support such that deformations imparted on said enclosure from the exterior are measurable by said measuring means directly or through resulting deformations of the partition wall.

11. The sensor of claim 10, wherein said measuring means are arranged such that variations of the curvature of said enclosure of said sensor are detectable.

12. The sensor of claim 11, wherein said measuring means are strain gauges.

13. The sensor of claim 10, wherein said support essentially extends along at least one diameter of said enclosure.

14. The sensor of claim 10, wherein the support comprises at least a first and a second bar which extend radially and essentially perpendicularly to each other such that a measurement of a radial deformation with the measurement being less dependent upon the angular orientation, and/or a distinction between different types of deformations is/are possible.

15. The sensor of claim 10, wherein the sensor is provided on its outside with projections such that said sensor is insertable into a cavity of a bar-shaped member with essentially only said projections contacting the inner side thereof.

16. The sensor of claim 10, wherein said sensor is provided with an orientation means that is operatively connectable to the bar-shaped member such that by said operative connection, said sensor is attachable to said bar in an alignment in which said sensor approximately has its highest sensitivity to the deformation of said bar-shaped member by a transversal load.

17. An aircraft comprising the device of claim 1.

18. An aircraft comprising the sensor of claim 10.