Device for monitoring the pressure of a vehicle tire

• US 5,400,649 A
• Filed: 07/02/1993
• Issued: 03/28/1995
• Est. Priority Date: 08/29/1990
• Status: Expired due to Term

• Current Assignee: Wabco Westinghouse Fahrzeugbremsen GmbH
• Original Assignee: Wabco Westinghouse Fahrzeugbremsen GmbH
• Inventors: Herzog, Stefan, Bartscher, Peter, Stegemann, deceased, Gerhard, Ulrich, Helmut
• Primary Examiner(s): Chilcot, Jr., Richard E.
• Assistant Examiner(s): Oen, William L.
• Application Number:
  US08/086,921
• Time in Patent Office: 634 Days
• Field of Search: 73/146.8, 73/146.5, 73/146.3
• US Class Current: 73/146.5
• CPC Class Codes: B60C 23/0408 transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver

Abstract

An apparatus is furnished for sensing the tire pressure and for generating a signal by way of an actuator. If the tire pressure drops below the predetermined reference tire pressure, then this is signalled immediately and instantly within a relatively small pressure tolerance threshold. The pressure sensitive device 1 includes a valve device 7. The valve device 7 connects the tire pressure, applied to the actuator 4 and acting against the force of the compression spring 6, to the atmosphere if the tire pressure drops below a predetermined reference tire pressure. The apparatus is suitable for generating a permanent signal, even in case no further pressure remains in a tire.

Claims

1. An apparatus for monitoring a pressure of a vehicle tire comprising

a vehicle wheel;

a tire mounted to the vehicle wheel;

a pressure inlet port connected to the interior of the tire;

a valve device having an inlet port, a control inlet port, and an outlet port, wherein the inlet port of the valve device is connected to the pressure inlet port, wherein the control inlet port is subjectable to a pressure present in the tire, and wherein the valve device is actuatable by the pressure present in the tire;

an actuator connected to the outlet port of the valve device and actuatable by the pressure present in the tire, wherein the actuator is subjected to a restoring force, wherein the valve device transmits the pressure present in the tire to the outlet port and to the actuator in a first switching position of the valve device in a situation where the tire pressure is at a predetermined or above the predetermined tire pressure and wherein the restoring force opposes the pressure present in the tire and transmitted to the actuator, wherein the valve device separates the pressure inlet port from the actuator in a second switching position of the valve device in a situation where the pressure present in the tire has dropped to below the predetermined tire pressure and wherein the valve device connects the actuator through a discharge port to the atmosphere in the second switching position of the valve device, and wherein the actuator generates a regulating distance (S) corresponding to a transition position value from the first switching position of the valve device to the second switching position of the valve device, and wherein the actuator thereby indicates a drop of the pressure present in the tire.

2. The apparatus according to claim 1 further comprising

a sensor for scanning the position of the actuator over a regulating distance S;

a transfer mechanism transferring the position of the actuator to the sensor.

3. The apparatus according to claim 2, wherein the transfer mechanism is formed by an elastic Bowden train.

4. The apparatus according to claim 1 further comprising

a mechanical signal device actuated by the actuator for generating an optically perceivable signal depending on the position of the actuator relative to the regulating distance (S).

5. The apparatus according to claim 1 further comprising

a mechanical signal device actuated by the actuator for generating an acoustically perceivable signal depending on the position of the actuator relative to the regulating distance S.

6. The apparatus according to claim 1 further comprising

a second tire;

a second pressure inlet port for monitoring the pressure of the second tire, wherein the second pressure inlet port is subjected to the pressure of the second tire;

a first pressure line connected to the first pressure inlet port of the first tire;

a second pressure line connected to the second pressure inlet port of the second tire;

a second valve device having a first port connected to the first pressure line and having a second port connected to the second pressure line, wherein the second valve device provides a switchable connection between the first port and the second port and is actuatable by the actuator for connecting and separating the first pressure inlet port and the second pressure inlet port,

wherein the second valve device actuatable by the actuator furnishes in a first switching position at a predetermined tire pressure and above the predetermined tire pressure a connection between the first pressure inlet port and the second pressure inlet port and below a predetermined tire pressure a separation of the first pressure inlet port from the second pressure inlet port.

7. The apparatus according to claim 1 further comprising

adjustment means furnished at the valve device for setting a pressure switching determining a pressure set point between the two positions of the valve device.

8. The apparatus according to claim 1, wherein the valve device control inlet port is connected to the pressure inlet port.

9. An apparatus for monitoring a pressure of a vehicle tire comprising

a pressure inlet port connectable to an interior of a tire;

a first valve device having an inlet port, a control inlet port, an outlet port and a discharge port, wherein the inlet port of the valve device is connected to the pressure inlet port, wherein the control inlet port is connected to the pressure inlet port for actuating the valve device depending on the pressure present at the pressure inlet port, wherein the valve device transmits the pressure present at the pressure inlet port to the outlet port in a first switching position of the valve device in a situation where the pressure at the pressure inlet port is at a predetermined pressure or above the predetermined pressure, wherein the valve device separates the pressure present at the pressure inlet port from the outlet port in a second switching position of the valve device in a situation where the pressure present at the pressure inlet port has dropped to below the predetermined pressure and wherein the valve device connects the outlet port through the discharge port to the atmosphere in the second switching position of the valve device;

an actuator connected to the outlet port of the valve device and actuatable by the pressure present at the outlet port, wherein the actuator is subjected to a restoring force, and wherein the restoring force opposes the pressure present at the outlet port and transmitted to the actuator, and wherein the actuator assumes a first positional value corresponding to a first switching position of the valve device, and wherein the actuator assumes a second positional value corresponding to the second switching position of the valve device, and wherein a transition of the actuator from the first positional value to the second positional value indicates a drop of the pressure present in the pressure inlet port.

10. The apparatus according to claim 9 further comprising

a wheel supporting the valve device and the actuator;

a tire mounted to the wheel and connected to the pressure inlet port,

wherein a distance between the first positional value and the second positional value is formed by a regulating distance (S).

11. The apparatus according to claim 9 further comprising

a sensor for scanning the positional values of the actuator;

a transfer mechanism transferring the positional values of the actuator to the sensor.

12. The apparatus according to claim 11, wherein the transfer mechanism is formed by an elastic Bowden train.

13. The apparatus according to claim 9 further comprising

a mechanical signal device acutuated by the actuator for generating an optically perceivable signal depending on the positional value of the actuator.

14. The apparatus according to claim 9 further comprising

a mechanical signal device actuated by the actuator for generating an acoustically perceivable signal depending on the positional value of the actuator.

15. The apparatus according to claim 9 further comprising

a second pressure inlet port connectable to a second tire;

a first pressure line connected to the first pressure inlet port;

a second pressure line connected to the second pressure inlet port;

a second valve device having a first port connected to the first pressure line and having a second port connected to the second pressure line, wherein the second valve device provides a switchable connection between the first port and the second port actuatable by the actuator for connecting and separating the first pressure inlet port and the second pressure inlet port, wherein the second valve device actuatable by the actuator furnishes in a first switching position at the predetermined tire pressure or above the predetermined tire pressure a connection between the first pressure inlet port and the second pressure inlet port and below a predetermined tire pressure a separation of the first pressure inlet port from the second pressure inlet port.

16. The apparatus according to claim 15 further comprising

a first wheel supporting the first valve device and the actuator;

a tire mounted to the first wheel and connected to the first pressure inlet port and wherein the first pressure inlet port is subjected to the pressure of the first tire;

a second tire connected to the second pressure inlet port for monitoring a pressure of the second tire, and wherein the second pressure inlet port is subjected to the pressure of the second tire.

17. The apparatus according to claim 9 further comprising

adjustment means furnished at the valve device for setting a pressure switching determining a pressure set point between two positions of the first valve device.

18. An apparatus for a monitoring of a pressure of a vehicle tire, including the following features:

a pressure sensitive device for scanning the tire pressure is furnished at a vehicle wheel, where the tire pressure sensitive device includes a pressure inlet port and wherein the pressure inlet port is connected to the tire;

an actuator is furnished, which can be subjected to the tire pressure against a restoring force, where the actuator serves for the generation of a regulating distance (S), indicating a tire pressure drop;

a valve device (7) is disposed between the pressure inlet port (2) and the actuator (4) and the valve device (7) is actuatable with the tire pressure, wherein the valve device (7) includes a control inlet port (8) and wherein the control inlet port (8) is subjectable to the tire pressure;

wherein the valve device (7) serves in a first switching position at a predetermined or above a predetermined tire pressure to connect the pressure inlet port (2) to the actuator (4);

wherein the valve device (7) serves in a second switching position below the predetermined tire pressure to separate the pressure inlet port (2) from the actuator (4) and to connect the actuator (4) through a discharge port (9) to the atmosphere.

19. The apparatus according to claim 18, wherein the restoring force (6), directed onto the actuator (4) and against the tire pressure, serves for generating the regulating distance (S) indicating a drop in tire pressure.

20. The apparatus according to claim 18, wherein a transfer mechanism (10) is furnished for the transfer of the regulating distance (S) to a sensor (12) scanning the regulating distance (S).

21. The apparatus according to claim 20, wherein the transfer mechanism (10) is formed of an elastic linkage (19), which linkage is an elastic Bowden train.

22. The apparatus according to claim 18, wherein the regulating distance (S), generatable with the actuator (4), serves for actuating a mechanical signal device, which allows to generate an optically or acoustically perceivable signal.

23. The apparatus according to claim 18, comprising a further pressure inlet port for monitoring the pressure of a second vehicle tire, wherein the further pressure inlet port (15) is subjected to the pressure of a second tire (16) and wherein the further pressure inlet port (15) is connected to the pressure inlet port (2) of the first tire (3) via a pressure line (17);

a valve device (18) actuatable by the actuator (4) generating the regulating distance (S), wherein the valve device (18) is disposed in the pressure line (17) and serves for connecting and separating the pressure inlet ports (2,

     15);

wherein the valve device (18), actuatable by the actuator (4), serves in a first switching position at a predetermined or above the predetermined tire pressure for connection of the pressure inlet ports 2, 15 and below a predetermined tire pressure for a separation of the pressure inlet ports (2,

     15).

24. An apparatus for a monitoring of a pressure of vehicle tires, comprising:

a pressure sensitive device (1) for scanning the tire pressure and furnished at a vehicle wheel, where the pressure sensitive device (1) includes a first pressure inlet port (2), and wherein the first pressure inlet port (2) is connected to the first vehicle tire (3);

an actuator (4), wherein the actuator is subjected to the tire pressure against a restoring force, and wherein the actuator serves for generating a regulating distance (S) indicating a tire pressure drop;

a first valve device (7), serving in a first switching position at a predetermined or above a predetermined tire pressure to connect the first pressure inlet port (2) to the actuator (4),

wherein the first valve device (7) serves in a second switching position below the predetermined tire pressure to separate the first pressure inlet port (2) from the actuator (4) and to connect the actuator (4) through a discharge port (9) to the atmosphere;

a second pressure inlet port (15) for monitoring the pressure of a second vehicle tire (16), wherein the second pressure inlet port (15) is subjected to the pressure of a second vehicle tire (16), and wherein the second pressure inlet port (15) is connected to the first pressure inlet port (2) of the first tire (3) via a pressure line (17);

a second valve device (18) actuatable by the actuator (4) generating the regulating distance (S), wherein the second valve device (18) is disposed in the pressure line (17) and serves for connecting and separating the first pressure inlet port (2) and the second pressure inlet port (15), wherein the second valve device (18), actuatable by the actuator (4), serves in a first switching position at a predetermined tire pressure and above the predetermined tire pressure to connect the first pressure inlet port (2) and the second pressure inlet port (15), and below a predetermined tire pressure to separate the pressure inlet port (2) from the pressure inlet port (15).

25. An apparatus for a monitoring of a pressure of vehicle tires, comprising:

a pressure sensitive device for scanning a tire pressure and furnished at a vehicle wheel, where the pressure sensitive device includes a first pressure inlet port, and wherein the first pressure inlet port is connected to the first tire;

a first valve device connected to the first pressure inlet port and serving to provide, in a first switching position at a predetermined or above a predetermined tire pressure, an open connection to the first pressure inlet port, and in a second switching below the predetermined tire pressure position a closing of the connection to the first pressure inlet port;

an actuator connected to the first valve device, wherein the actuator is subjected to the tire pressure when the first valve device provides an open connection and against a restoring force, and wherein the actuator serves for generating a regulating distance indicating a tire pressure drop, and wherein the first valve device serves in the second switching position below the predetermined tire pressure to separate the first pressure inlet port from the actuator and to connect the actuator through a discharge port to the atmosphere;

a second pressure inlet port to be connected to a second vehicle tire and for monitoring a pressure of a second vehicle tire, wherein the second pressure inlet port is subjected to the pressure of the second vehicle tire;

a pressure line connecting the second pressure inlet port to the first pressure inlet port of the first vehicle tire;

a second valve device disposed in the pressure line and actuatable by the actuator generating the regulating distance, wherein the second valve device serves for connecting and separating the first pressure inlet port and the second pressure inlet port,

wherein the second valve device is actuatable by the actuator into a first switching position and into a second switching position, wherein the second valve device serves in a first switching position at a predetermined or above the predetermined tire pressure to connect the first pressure inlet port and the second pressure inlet port, and wherein the second valve device serves below a predetermined tire pressure to separate the first pressure inlet port from the second pressure inlet port.