Device for measuring the wear of a ball-and-socket joint, ball-and-socket joint incorporating said device and method for measuring the wear of such a ball-and-socket joint

1. A device for measuring the wear of a ball-and-socket joint comprising:

a first ring, which delimits a spherical housing;

a second spherical ring, which is positioned concentrically in the housing of the first ring;

a lining, which is made from an electrically insulating material and, which is interposed between the second ring and the spherical housing of the first ring,

wherein the device is placed in a filling of a fabric of the lining and adapted to measure the wear of the lining by including:

at least two electrodes comprising a first electrode connected to a first connection point of the lining and a second electrode connected to a second connection point of the lining to form a capacitor structure, and

a capacitance measuring feature for measuring a capacitance of the capacitor structure thus formed;

an electronic circuit, which is a resonant circuit including the capacitor structure, an inductance and a resistance positioned in series; and

a radio identification marker incorporated into the ball-and-socket joint, the radio identification marker communicating and transmitting a value of the capacitance of the capacitor structure and a reference number of the ball-and-socket joint to a receiver, the radio identification marker being a radio tag comprising an antenna.

2. The device according to claim 1 , wherein:

the electronic circuit is a short-circuited line, and

the capacitance measuring feature for measuring the capacitance of the capacitor structure includes a reflectometer and an excitation module that are positioned on one side of the line.

3. A ball-and-socket joint, comprising:

a first ring, which delimits a spherical housing;

a second spherical ring, which is positioned concentrically in the spherical housing of the first ring,

a lining, which is made from an electrically insulating material and which is interposed between the second ring and the spherical housing of the first ring,

a device for measuring wear, wherein the device is placed in a filling of a fabric of the lining and adapted to measure the wear of the lining by including:

at least two electrodes comprising a first electrode connected to a first connection point of the lining and a second electrode connected to a second connection point of the lining to form a capacitor structure,

a capacitance measuring feature for measuring a capacitance of the capacitor structure thus formed;

an electronic circuit, which is a resonant circuit including the capacitor structure, an inductance and a resistance positioned in series; and

a radio identification marker incorporated into the ball-and-socket joint, the radio identification marker communicating and transmitting a value of the capacitance of the capacitor structure and a reference number of the ball-and-socket joint to a receiver, the radio identification marker being a radio tag comprising an antenna.

4. The ball-and-socket joint according to claim 3 , wherein the measuring device is incorporated into a housing delimited on an inner radial surface of the first ring.

5. A method for measuring the wear of a ball-and-socket joint, the method comprising:

accessing a ball-and-socket joint comprising:

a first ring, which delimits a spherical housing,

a second spherical ring, which is positioned concentrically in the housing of the first ring,

a lining, which is made from an electrically insulating material and, which is interposed between the second ring and the spherical housing of the first ring,

a measuring device placed in a filling of a fabric of the lining,

measuring by the measuring device the wear of the lining by forming a capacitor structure from at least two electrodes comprising a first electrode connected to a first connection point of the lining and a second electrode connected to a second connection point of the lining;

measuring a capacitance of the capacitor structure thus formed by a capacitance measuring feature; and

communicating and transmitting by a radio identification marker a value of the capacitance of the capacitor structure and a reference number of the ball-and-socket joint to a receiver; the radio identification marker being incorporated into the ball-and-socket joint, the radio identification marker being a radio tag comprising an antenna.

6. The method according to claim 5 , wherein step of measuring the capacitance of the capacitor structure is accomplished by exciting a resonant circuit with an electric pulse, which is a wave whereof the frequency is equal to the resonance frequency of the electronic circuit for a predetermined capacitance value.

7. The method according to claim 6 , wherein the predetermined capacitance value is equal to the capacitance of the capacitor structure in new condition.

8. The method according to claim 6 , wherein variation of the capacitance of the capacitor structure, due to wear of the ball-and-socket joint, causes a change in resonance frequency of the electronic circuit and the formation of a reflected wave at the end of the line, which is measured by a reflectometer.

9. The method according to claim 8 , wherein the capacitance of the capacitor structure is deduced from a ratio between the resonance frequency of the circuit for a predetermined capacitance value, and the frequency of the reflected wave.