Device for transmission and evaluation of measurement signals for the tire pressure of motor vehicles

• US 5,033,295 A
• Filed: 02/04/1989
• Issued: 07/23/1991
• Est. Priority Date: 05/04/1988
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Schmid, Gu, Hettich, Gerhard, Genzel, Michael
• Primary Examiner(s): Orsino, Joseph A.
• Assistant Examiner(s): Swarthout, Brent
• Application Number:
  US07/457,749
• Time in Patent Office: 899 Days
• Field of Search: 73/146.5, 73/146.4, 340/445, 340/447, 340/448, 340/442, 116/34 R, 200/61.22
• US Class Current: 73/146.5
• CPC Class Codes: B60C 23/007 having multiple wheels arranged side by side
• CPC Class Codes: B60C 23/0428 using passive wheel mounted resonance circuits

Abstract

In a device for the transmission and evaluation of measurement signals for the tire pressure of tubless tires mounted rims in single and twin wheels of motor vehicles which comprises a pressure sensor (6) arranged in the rim wall, which pressure sensor (6) is electrically connected with a signal transmitter coil (8) arranged at the rim (3), as well as a signal pick-up coil (20) of a high-frequency resonant circuit signal evaluating arrangement connected with the motor vehicle in the area of the axle so as to be stationary, it is provided for the purpose of enabling signal detection also when stationary and for problem-free application to twin tires, that a first repeater coil (15), which is electrically connected with a second repeater coil (17), is arranged in the area of the signal transmitter coil (8) at the hub (12) carrying the rim (3), which hub (12) is connected with the latter so as to be fixed with respect to rotation relative to it, wherein the second repeater coil (17) is constructed as a toroidal coil whose coil axis (18) coincides with the hub axis (11), wherein the stationary signal pick-up coil (20) is arranged in the magnetic field area of the second repeater coil (17).

Claims

1. A device for transmitting and evaluating measurement signals of tire pressure in single and twin wheels of motor vehicles with each wheel including a hub having a hub axis, a rim supported on the hub for joint rotation therewith, and a tubeless tire mounted on the rim, said device comprising a sensor arranged in a rim wall;

a signal transmitter coil arranged at the rim;

first conductor means for electrically connecting a pressure sensor with said signal transmitter coil;

high-frequency resonant circuit signal evaluating means located in vicinity of an axle of a motor vehicle, fixed stationary with respect to the motor vehicle, and including a signal pick-up coil;

a first repeater coil arranged on the hub in an area of said signal transmitting coil;

a second repeated coil;

second conductor means for electrically connecting said first and second repeater coils, said second repeater coil being formed as a toroidal coil having an axis that coincides with the hub axis, said signal pick-up coil being arranged in a magnetic field of said second repeater coil; and

means for enabling mounting of the rim in a predetermined angular position on the hub in which said signal transmitter coil and said first repeater coil are located opposite each other.

3. A device according to claim 1, wherein said means for enabling mounting of the rim in a predetermined angular position are formed as catch means.

4. A device according to claim 1, wherein the rim comprises a rim cup base, said signal transmitter coil and said first repeater coil being located in an area of the rim cup base.

5. A device according to claim 1, wherein each of said signal transmitter coil and said first repeater coil has an axis extending parallel with respect to the hub axis, and an end surface which is aligned with an opposite end surface of another of said signal transmitter coil and said first repeater coil.

6. A device according to claim 1, wherein said high-frequency resonant circuit signal evaluating means includes discriminator means for distinguishing at least between three different frequency levels and for generating respective output signals.

2. A device for transmitting and evaluating measurement signals of tire pressure in twin wheels of motor vehicles with each wheel including a hub having a hub axis, a rim supported on the hub for joint rotation therewith, and a tubeless tire mounted on the rim, said device comprising a sensor arranged in a rim wall;

two signal transmitter coils arranged at the respective rim walls so as to be adjacent to each other;

first conductor means for electrically connecting a pressure sensor with said signal transmitter coils;

high-frequency resonant circuit signal evaluating means located in vicinity of an axle of a motor vehicle, fixed stationary with respect to the motor vehicle, and including a signal pick-up coil;

a common first repeater coil arranged on the hub opposite to said two signal transmitting coils;

a second repeater coil;

second conductor means for electrically connecting said first and second repeater coils, said second repeater coil being formed as a toroidal coil having an axis that coincides with the hub axis, said signal pick-up coil being arranged in a magnetic field of said second repeater coil, each of said signal transmitter coil and said first repeater coil having an axis extending parallel with respect to the hub axis, and an end surface which is aligned with an opposite end surface of another of said signal transmitter coil and said first repeater coil, said two transmitter coils being magnetically coupled with said common first repeater coil.