Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
  • B60C23/02—Signalling devices actuated by tyre pressure
  • B60C23/04—Signalling devices actuated by tyre pressure mounted on the wheel or tyre
  • B60C23/0408—Signalling devices actuated by tyre pressure mounted on the wheel or tyre transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
  • B60C23/0474—Measurement control, e.g. setting measurement rate or calibrating of sensors; Further processing of measured values, e.g. filtering, compensating or slope monitoring
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
  • B60C23/02—Signalling devices actuated by tyre pressure
  • B60C23/04—Signalling devices actuated by tyre pressure mounted on the wheel or tyre
  • B60C23/0408—Signalling devices actuated by tyre pressure mounted on the wheel or tyre transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
  • B60C23/041—Means for supplying power to the signal- transmitting means on the wheel
  • B60C23/0413—Wireless charging of active radio frequency circuits
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
  • B60C23/02—Signalling devices actuated by tyre pressure
  • B60C23/04—Signalling devices actuated by tyre pressure mounted on the wheel or tyre
  • B60C23/0408—Signalling devices actuated by tyre pressure mounted on the wheel or tyre transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
  • B60C23/0422—Signalling devices actuated by tyre pressure mounted on the wheel or tyre transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver characterised by the type of signal transmission means
  • B60C23/0433—Radio signals
  • B60C23/0447—Wheel or tyre mounted circuits
  • B60C23/0455—Transmission control of wireless signals
  • B60C23/0462—Structure of transmission protocol
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C23/00—Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements
  • B60C23/02—Signalling devices actuated by tyre pressure
  • B60C23/04—Signalling devices actuated by tyre pressure mounted on the wheel or tyre
  • B60C23/0408—Signalling devices actuated by tyre pressure mounted on the wheel or tyre transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
  • B60C23/0471—System initialisation, e.g. upload or calibration of operating parameters

Definitions

• the IC chip and other components are mounted and/or connected to a substrate such as a printed circuit board (PCB).
• PCB printed circuit board
• Figure 3B is a schematic diagram of a portion of the RF transponder of Figure 2, according to the invention
• Figure 3C is a diagram of a memory space within the RF transponder of Figure 2, illustrating how data may be arranged and transmitted, according to the invention
• FIG. 2 is a block diagram of the RF transponder 200 (compare 102) of the present invention, illustrating the major functional components thereof.
• This exemplary system is described as an embodiment which preferably measures pressure and temperature, but it is within the scope of the invention to include measurement of other parameters which employ suitable sensors.
• the timing generator/sequencer circuit 226 controls when the external pressure- sensing capacitance (C P ) 218 is included in the generation of a signal at frequency Fosc' which is output by the relaxation oscillator 252, and also controls the capturing of the pressure and temperature counts via the data capture circuit 254. For example, to measure temperature, the temperature-sensitive current I(T) passes through the internal oscillator capacitors (Cpx-, and C ⁇ ), but the pressure-sensing capacitor (C P ) 218 is disconnected from (not included in) those capacitances. This means that the frequency Fosc' of the oscillator output signal seen on line 253 is a function of temperature alone.
• the current scaling circuit 310 (also part of the base-emitter voltage-to-current converter 250 of Figure 2) is constructed in the following exemplary manner.
• the sources of the transistors P5 and P6 are connected to supply voltage Vdd.
• the gate of a transistor N6 receives the reference voltage (Nbias) on the line 309.
• the transistor N6 is connected in a current-mirroring configuration with the transistor N5 (as well as with the aforementioned transistor N4) and will therefore mirror the flow of current I(T) through the transistors N4 and N5. Consequently, the flow of current through the diode-connected transistor P5 will mirror the flow of current through the transistors N4, N5 and N6.
• Temperature is suitably measured by counting the number of cycles output from the oscillator 312 during a fixed time period (window W ⁇ of time from tO to tl) having a time period t,-.
• a down-counter (not shown, but associated with the temperature register 232) may be clocked by the oscillator, such that at the end of the window W ⁇ time period t,-, a temperature count N ⁇ is generated.
• the relationship between temperature count N ⁇ and temperature is substantially linear for the circuitry 300 of this embodiment.
• the positive (+) inputs (terminals) of the comparators 316a and 316b are tied together and are set to a reference "bandgap" voltage Vbg, such as 1.32 volts, which is independent of temperature.
• Vbg the reference bandgap voltage
• the supply voltage (Vdd) on the line 309' may be provided as a multiple of the reference bandgap voltage (Vbg) so as to be a stable operating voltage for the current scaling circuit 310 and the relaxation oscillator 312.
• Figure 3B illustrates a circuit 370 suitable for generating the supply voltage Vdd.
• a temperature-independent calculable bandgap voltage Vbg is readily derived, based on the processing techniques employed in fabricating the IC chip, as being inherent to the selected process (e.g., CMOS).
• This bandgap voltage Vbg is provided to the positive (+) input of an operational amplifier 372, connected as shown, in a feedback loop having gain, to provide supply voltage Vdd as an integral multiple of the bandgap voltage Vbg.
• Figure 3C illustrates an exemplary architecture for information which is stored in memory (e.g., 238) within the transponder 200, as well as a data stream which is transmitted by the transponder 200 to the external reader/interrogator 106, 166.
• the memory 238 of the transponder core 204 has, for example, a 144-bit address space which includes 119 (one hundred nineteen) bits of programmable memory and one address location dedicated to the state of the MTMS switch 220 - these 120 (one hundred twenty) bits of programmable memory constituting the EEPROM 136 - plus two 12-bit temperature and pressure registers 232 and 234, respectively.
• a defining point 508, the significance of which is discussed below, is shown at the coordinate (T.,N T1 ) on the line 506.
• ni p (N ⁇ /N Pg00 ⁇ 25 - N T /N P60025 )/(800-600) [EQ. 6]
• the value of ni p is a positive number, and must fall within a predetermined, acceptable range (as determined by the range check on N Pg0025 - N P60025 ). Any transponder having a pressure response slope falling outside of this range can be rejected.
• a binary conversion is performed, and the result is assigned a suitable number of binary bits (e.g., 7 bits).

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Computer Networks & Wireless Communication (AREA)
• Measuring Fluid Pressure (AREA)

Priority Applications (8)

Applications Claiming Priority (1)

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Publications (1)

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Family Applications (1)

Country Status (5)

Cited By (8)

Families Citing this family (4)

Citations (5)

• 1999
  • 1999-12-14 JP JP2001545104A patent/JP2003517150A/ja active Pending
  • 1999-12-14 WO PCT/US1999/029606 patent/WO2001043997A1/en not_active Application Discontinuation
  • 1999-12-14 EP EP99967303A patent/EP1240035A1/en not_active Withdrawn
  • 1999-12-14 AU AU23608/00A patent/AU2360800A/en not_active Abandoned
  • 1999-12-14 BR BR9917580-0A patent/BR9917580A/pt not_active IP Right Cessation

Patent Citations (5)

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