Passive measuring instrument for measuring tire air parameters and wheel angular velocity

Abstract

A passive measuring instrument for measuring air parameters in a tire and angular velocity of a wheel, comprising a structural element generating a magnetic field on a wheel or a t-type tire; a pressure and temperature sensor generating a magnetic field when the wheel rotates in an external magnetic field, the magnetic field generated by the sensor depending on the air pressure and temperature, respectively; a signal generator mounted near the wheel and generating an external magnetic field, and also generating a voltage in response to the magnetic field action of the structural element, the voltage being used to power the passive components of the measuring instrument and to determine the angular velocity, the signal generator also generating an electrical signal in response to the magnetic field action of the sensor, the electrical signal being used to determine an air parameter; a passive wireless data transmission assembly is electrically coupled to the signal generator that identifies air parameters and angular velocity data and transmits the data to a wireless data display assembly via an audio channel, or to a passive wired data display assembly that forms a circuit with the signal generator.

Description

Technical Field

[0001] The invention relates to transport engineering and can be used in the automotive and tractor industries.

[0002] When operating a vehicle, the air pressure in the tires needs to be monitored to avoid high and low pressure. Low tire pressure will lead to increased tire deformation, which will increase tire wear, increase tire temperature, affect tire strength, and increase fuel consumption. When the air pressure in the tire exceeds the required pressure, the contact area between the tire and the road will be reduced, resulting in rapid wear in the middle of the tire.

[0003] When a vehicle is driven with a brake system malfunction, such as when the brake pads are stuck, the air in the tires becomes hotter, so measuring the air temperature can monitor the health of the brake system. Background Art

[0004] In order to avoid safety problems caused by air pressure in tires and ensure safe driving, various types of tire pressure monitoring devices have been developed. Currently, there are two completely different types of tire pressure monitoring devices in use: one is a monitoring device that directly measures tire pressure and air temperature; the other is a device that monitors tire pressure changes by indirectly evaluating pressure changes.

[0005] The various devices that monitor the air pressure and air temperature in the tire by direct measurement differ in the installation location of the sensor unit with the pressure and temperature sensors: the monitoring device with an internal sensor unit is installed on the outer surface of the rim inside the tire; the control unit with an external sensor module is installed on the tire valve. All sensor units use an encrypted radio frequency channel to transmit the tire pressure and temperature values ​​to the monitor inside the car. All sensor units also contain the pressure and temperature sensors and the power supply for the radio transmitter.

[0006] In a pressure monitoring device that indirectly evaluates changes in tire pressure, this change is determined by evaluating the difference in the rotational angular velocity of all wheels. In a car with an ABS system, the rotational angular velocity of each wheel is determined by an existing sensor. When the rolling radius of the tire changes due to changes in the air pressure inside the tire, a difference in wheel speed occurs. Compared to the rotational angular velocity of the other three wheels of the vehicle with the tire at normal pressure, the rotational angular velocity of the other wheel on which the tire is installed increases as the target tire pressure decreases and decreases as the pressure increases.

[0007] The disadvantages of the pressure monitoring system that indirectly monitors tire pressure changes are: the pressure monitoring system does not measure the target tire pressure, but the change of the target tire pressure relative to the pressure of other wheels; the pressure change detection time is relatively long (about 10 minutes); only significant changes in tire pressure can be detected; changes in tire rolling radius caused by uneven vehicle loading will cause errors; and operation cannot be performed when the pressure changes of all tires of the vehicle are the same.

[0008] The disadvantages of control systems with direct measurements compared to those with indirect measurements are: high cost; lower reliability due to the complexity of the radio equipment; difficulty in maintaining the system during operation; limited service life of the power supply; and various problems caused by the use of electromagnetic radiation to connect the monitor and sensor units.

[0009] One direction to solve the problem of creating a simple device for directly measuring tire pressure and temperature is to develop a device that does not contain complex radio equipment mounted on the rim and requires a power source to operate, such as a radio transmitter, electronic pressure and temperature sensors, etc.

[0010] The above device has many advantages, such as: simple design; high reliability; low price; extended service life; easy maintenance; the pressure and temperature information of the wheel is transmitted by induction, thus eliminating the problems associated with the use of electromagnetic waves.

[0011] A device for monitoring the tire pressure of a car is known (International Application No. PCT No. 80 / 02837, B60C23 / 04, 1986). The device comprises a pressure sensor, the inner cavity of which communicates with the inner cavity of the tire. The air pressure from the tire acts on a moving element, which is acted on in the opposite direction by a spring. The movement of the moving element is fixed by two switches that generate corresponding signals.

[0012] The movement of the moving element is fixed by two switches that generate corresponding signals. The transmitter in the device has an excitation winding system that provides a time-varying current to the winding according to the signal of the pressure sensor, thereby generating a magnetic field that drives the receiver and generates a signal proportional to the tire pressure. The disadvantages of this device are large size, complex design and insufficient reliability, which are caused by the fact that the device includes switches, moving elements, excitation system and power supply mounted on the wheel.

[0013] A possible solution to this problem is implemented in a device for monitoring the tire pressure of a car (Russian Patent No. 2009898, B60C23 / 04, 1992). There is a primary circular coil inductor on the inner surface of the rim, which is connected by a wire through a hole in the rim to a circuit with an electric pressure sensor, which is located on the outer surface of the rim inside the tire. When the air pressure in the tire changes, the sensor changes the resistance in the circuit. There is a signal receiving unit near the rim, which consists of a cylindrical permanent magnet and a secondary circular coil inductor. One end of the cylindrical permanent magnet is located on the bracket, and the secondary circular coil inductor is located at the other end of the permanent magnet, facing the rim.

[0014] When the primary coil inductor moves near the signal receiving unit and is exposed to the magnetic field of the cylindrical permanent magnet of the signal receiving unit, the primary coil inductor generates an induced current, the strength of which depends on the resistance of the circuit, that is, on the air pressure in the tire. The induced current generates its own magnetic field in the primary coil inductor, which depends on the air pressure in the tire. When exposed to the variable own magnetic field of the primary coil inductor, a variable electromotive force is induced in the secondary coil inductor, which depends on the air pressure in the tire. The variable electromotive force is an electrical signal that is transmitted via wires to the warning device on the driver's side.

[0015] The electronic pressure sensor in the form of a membrane key opens the circuit when the tire pressure drops below a certain threshold. The intensity of the induced current then becomes zero. An electrical signal is then sent to the warning device, which informs the driver with optical and acoustic signals that the pressure has fallen below the threshold.

[0016] A working model of a device for monitoring car tire pressure was presented at the 1996 Eureka World Invention Fair in Brussels and was awarded a diploma and a bronze medal.

[0017] A prototype of a car tire pressure monitoring device was tested at the Moscow JSC Moskvychi Automobile Plant in 1999. The tests confirmed the physical basis of a measuring system with inductive signal transmission from a moving object to a stationary measuring unit, which was used to develop a car tire pressure monitoring device.

[0018] In particular, mathematical models of electrical signals and voltages are confirmed theoretically and experimentally.

[0019] The design closest to the present invention is "Passive measuring instrument for automobile tire pressure and air" (Russian Patent No. 2509656, B60C23 / 04, 2012).

[0020] The passive measuring instrument comprises an electronic pressure sensor mounted on the rim that changes its resistance according to the air pressure in the tire, a primary coil inductance connected in an electrical circuit, an electronic temperature sensor that changes its resistance when the air temperature in the tire changes, and an additional primary coil inductance connected in an electrical circuit, one or more permanent magnets, and / or one or more areas of the rim having a magnetic permeability different from the magnetic permeability of the material of which the rim is made, and / or one or more protrusions, and / or one or more depressions.

[0021] On a fixed part of the car, there are a permanent magnet, a secondary coil inductor, and an active device powered by electricity from a power source connected to the secondary coil inductor in a circuit, or a passive device without a power source connected to the secondary coil inductor in a circuit for wirelessly transmitting information to a signaling device installed inside the car. Summary of the invention

[0022] The claimed invention "a passive measuring instrument for measuring air parameters in a tire and angular velocity of a wheel" comprises a structural element for generating a magnetic field mounted on a rim or tire, and sensors for pressure and temperature generated when the wheel rotates in an external magnetic field and its own magnetic field that depend on pressure and temperature, respectively. A signal generator is mounted near the edge of the wheel or tire, generates an external magnetic field, generates an electrical signal that depends on pressure (temperature) when exposed to the magnetic field of the pressure (temperature) sensor itself, and generates a voltage when the wheel rotates and is exposed to the magnetic field of the structural element. When wireless information transmission is performed, a passive wireless information transmission node having software for processing the electrical signal and voltage is mounted near the signal generator and is connected to the signal generator by a circuit to determine information about pressure, temperature, angular velocity, and angular acceleration of the wheel, and the power supply of the passive wireless information transmission node is borne by the electrical signal and voltage.

[0023] The objects of the invention claimed for protection are:

[0024] 1. Measure the angular velocity and angular acceleration of the wheel;

[0025] 2. Maintaining the integrity of the rim, which is made of a material with a much larger unit magnetic permeability (such as steel), when placing pressure and temperature sensors inside the tire;

[0026] 3. Transmit information from a passive wireless transmission information node to a wireless information display node without using electromagnetic waves.

[0027] The first objective is achieved by using software for processing electrical signals and voltages installed on the corresponding nodes of the passive measuring instrument. For example, a pressure sensor and a temperature sensor are installed on the rim of a wheel of radius r, at a known distance S from each other, and based on the measurement time interval ΔT between the recording times of the electrical signals from said pressure sensor and temperature sensor, along the arc of the rim, the average angular velocity ω within this time interval is estimated. cp

[0028] v=S / Δt,ω cp =v / r.

[0029] Similarly, the average angular velocity is estimated using any other measured time intervals between the times when the electrical signal and voltage are recorded. MΓ The estimation is based on the dependence of the known voltage parameters on the wheel angular velocity: voltage amplitude A = f(ω), voltage duration The voltage form obtained theoretically and confirmed experimentally. For example, according to the formula From the measured amplitude value Estimate the instantaneous angular velocity, where the function f -1 (A) is the inverse function of f(ω), according to the formula From the measured amplitude value Estimate the instantaneous angular velocity, where It is the inverse function of the function φ(ω).

[0030] The average angular acceleration over the time interval ΔT is estimated based on the angular velocity estimation result: According to the formula ε cp =(ω κ -ω H ) / ΔT, the time interval starts at ω H , at the end of the time interval, ω κ .

[0031] The knowledge of the angular velocity of the wheel rotation is necessary for the operation of the detection algorithms, the estimation of the parameters of the electrical signals and, therefore, for the estimation of pressures and temperatures. If necessary, the information about the angular velocity of the wheel can be transmitted to other vehicle systems whose operation requires knowledge of the angular velocity of the wheel, such as the anti-lock braking system (ABS), the electronic stability program (ESP).

[0032] It is well known that a plate made of a magnetic material with high magnetic permeability can shield the magnetic field, i.e. if a permanent magnet is located in front of the plate, there is no magnetic field behind the plate. This happens when a pressure (temperature) sensor is placed on the outer surface of a steel wheel rim inside the tire and a signal generator generating an external magnetic field is placed near the inner surface of the rim.

[0033] In this case, to ensure the operation of the pressure (temperature) sensor, the part of the sensor that generates its own magnetic field must be placed on the inner surface of the rim, while the part of the sensor that determines the dependence of its own magnetic field on pressure (temperature) must be placed on the outer surface of the rim inside the tire. Figure 1 As shown in Figure 1, the electrical connection of the sensor parts is achieved through the holes in the rim.

[0034] The second object is achieved by the following: in the case of a wheel with a steel rim, the pressure (temperature) sensor is located inside the tire, but not on the rim, but on the tire itself. For example, one possibility is to place the pressure (temperature) sensor on the sidewall of the tire, such as Figure 4 As shown in item 14. The material used to make the tire sidewall is non-magnetic, so the external magnetic field of the signal generator located near the tire exists inside the tire, and the sensor's own magnetic field generates an electrical signal in the signal generator.

[0035] When a wheel whose rim is made of a non-magnetic material with low magnetic permeability is used, the external magnetic field is not shielded and the pressure (temperature) sensor can be mounted on the outer surface of the rim inside the tire.

[0036] The third object is achieved by the fact that the wireless information transmission node contains a generator and transmitter of sound waves and information transmission is performed by means of encoded sound signals.

[0037] The passive measuring instrument will only work when the vehicle is moving and exceeds the set minimum speed. Studies have shown that by properly selecting the parameters of the signal generator, pressure and temperature sensors, a minimum operating speed of 2-4km / h is recommended.

[0038] Passive measuring instruments offer many advantages over known devices for monitoring tire pressure and air temperature by direct measurement, such as:

[0039] 1. Passive pressure gauges do not require power;

[0040] 2. No radio transmitters, electronic pressure sensors or electronic temperature sensors or moving mechanical parts;

[0041] 3. The inductive transmission of wheel or tire electrical signals and voltage does not use an electromagnetic wave signal generator;

[0042] 4. The pressure (temperature) sensor has a simple design, small size, and light weight. It is preferably made of a coil inductor and a pressure (temperature) resistor in a circuit form, that is, the resistance of the resistor depends on the air pressure (temperature) in the tire, and the cost is low;

[0043] 5. Pressure (temperature) sensors may be used on wheels with both tubed and tubeless tires;

[0044] 6. Simple design, small size and weight of the signal generator, preferably made of coil inductance and permanent magnet, low cost;

[0045] 7. Ability to use wired transmission of signal generator and wired information display node, which eliminates many problems that occur during wireless communication;

[0046] 8. Ability to use sound waves for wireless information transmission, eliminating many problems that arise when using electromagnetic waves

[0047] 9. Low cost of passive measuring instruments for multi-wheel long-distance trains; wheel angular velocity measured using passive measuring instruments may make it possible for the vehicle to no longer use other angular velocity measurement systems, thereby reducing the price of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 The arrangement of the components of the device in patent No. 2009898 is shown in the figure, explaining its operating principle, wherein the following figure numbers are used:

[0049] 1. Primary circular coil inductor, diameter 16 mm, thickness 2 mm, weight 2 g;

[0050] 2. Electronic pressure sensor, made into a membrane keypad with a diameter of 30 mm and a weight of 6 g;

[0051] 3. A signal receiving node, comprising a cylindrical permanent magnet and a secondary circular coil inductor;

[0052] 4. Cylindrical permanent magnet, diameter 16 mm, height 6 mm, weight 33 g;

[0053] 5. The inductance of the secondary coil is similar to that of the primary coil;

[0054] 6. Signaling device;

[0055] 7. Rim;

[0056] 8. Tires;

[0057] 9. Bracket;

[0058] 10. Brake drum protection;

[0059] 11. Wire;

[0060] 12. Brake drum;

[0061] 13. Layout of equipment components on wheels;

[0062] Figure 2 Photograph showing the diploma and medal awarded at the 1996 Eureka World Invention Fair in Brussels.

[0063] Figure 3 It shows:

[0064] A - the title page of the test report of the Moscow Automobile Plant of JSC Moskvychika;

[0065] B-Test report summary;

[0066] exist Figure 4 One of the possible layouts of nodes for passive measuring instruments for measuring tire air parameters and wheel angular velocity is shown in FIG. 1 , wherein the following figure numbers are used:

[0067] 14. Pressure (temperature) sensor;

[0068] 15. Structural elements;

[0069] 16.Signal generator;

[0070] 17. Wires connecting the signal generator to the wireless transmission node information;

[0071] 18. Wireless transmission node information.

[0072] Embodiments of the invention

[0073] The operation of the passive measuring instrument for measuring air parameters in the tire and wheel angular velocity discussed in this particular embodiment is as follows, and this embodiment is not a limitation on the implementation of the present invention.

[0074] When the wheel 7 rotates, the pressure (temperature) sensor 14 moves in the external magnetic field of the signal generator 16. The pressure (temperature) sensor is preferably manufactured in the form of a circuit consisting of an inductor coil and a pressure (temperature) resistor, generating an induced current, the parameters of which are determined by the resistance of the pressure (temperature) resistor. The induced current generates a magnetic field of the pressure (temperature) sensor itself, so that an electromotive force is generated in the inductor coil of the signal generator. The induced current is preferably formed by a permanent magnet and an inductor coil, and is an electrical signal with parameters that depend on the air pressure (temperature).

[0075] Also in the signal generator, when the wheel rotates, exposed to the magnetic field of the structural element 15 (preferably a permanent magnet), a voltage is generated according to the angular velocity of the wheel.

[0076] The electrical signal and voltage from the signal generator are transmitted via wires to the wired information display node installed inside the vehicle. The software of the wired information display node determines the relevant information about pressure, temperature, angular velocity, and wheel angular acceleration. The relevant information about pressure and temperature is displayed through sound and light signals. If necessary, the wired information display node transmits the wheel number and wheel angular velocity to other vehicle systems, such as the anti-lock braking system (ABS) and the electronic stability program (ESP).

[0077] When the wired information display node is activated, the node contains a power supply or is powered by the vehicle electrical system. When the wired information display node becomes passive, its power supply is provided by the electrical signal and voltage from the signal generator. In order to wirelessly transmit information to the wireless information display node, the signal generator is connected via a wire 17 to a wireless information transmission node 18 installed next to the signal generator, and the wireless information transmission node is equipped with software for processing electrical signals and voltages to determine relevant information about air parameters and wheel angular velocity. The transmission of relevant information to the wireless information display node can be performed, for example, by using a coded audio channel of sound waves. When the wireless information transmission node is passive, its power supply is provided by the electrical signal and voltage from the signal generator.

Claims

1. A passive measuring instrument for measuring air parameters in a tire and wheel angular velocity, comprising a structural element for generating a magnetic field mounted on a rim and / or a tire; The invention comprises at least one permanent magnet; and / or at least one element made of a material having a magnetic permeability and / or electrical conductivity different from that of the rim and / or tire material; and / or at least one protrusion; and / or at least one groove on the inner surface of the wheel rim; characterized in that at least one pressure sensor is mounted on the wheel rim and / or the tire, and when the wheel rotates in an external magnetic field, the pressure sensor generates its own magnetic field according to the air pressure in the tire; and / or at least one temperature sensor, when the wheel rotates in an external magnetic field, the temperature sensor generates its own magnetic field according to the air temperature in the tire; the temperature sensor is mounted on the inner surface of the rim and / or the outer surface of the tire; at least one signal generator generates an external magnetic field, and when the exposure When exposed to the magnetic field of the pressure sensor itself or the magnetic field of the temperature sensor itself, an electrical signal is generated according to the air pressure or temperature in the tire respectively; and when exposed to the magnetic field of the structural element, the signal generator generates a voltage; the structural element is installed near the signal generator; at least one wireless information transmission node forms a circuit with at least one signal generator and is equipped with a controller and built-in corresponding software for processing the electrical signal and the voltage to determine relevant information about the pressure and / or temperature of the air in the tire installed on the wheel, and / or the angular velocity and / or angular acceleration of the wheel; the wireless information transmission node includes at least one electromagnetic wave generator having at least one antenna for emitting electromagnetic waves; and / or at least one acoustic wave transmitter having at least one electromagnetic wave transmitter a sound wave generator of the device; in this case, the relevant information is transmitted by using a coded radio channel of electromagnetic waves and / or by using a coded audio channel of sound waves; in addition, when the wireless information transmission node is passive (does not contain a power supply and is not connected to the electrical system of the vehicle), the power supply is performed by the electrical signal and / or voltage of the signal generator, wherein the passive wireless information transmission node contains an energy storage device containing at least one battery, and / or at least one capacitor, at least one wireless information transmission node; at least one signal generator can be combined in at least one unit; on the vehicle, preferably in the cabin, at least one wireless information display node is installed, the wireless information display node includes a controller and built-in corresponding software and at least an electromagnetic wave receiving antenna and / or at least one sound wave receiver, and capable of displaying the wheel number and corresponding information about tire pressure and / or temperature received from the wireless information transmission node; if necessary, transmitting information about the wheel number and its angular velocity to other vehicle systems, such as an anti-lock braking system (ABS), an electronic stability program (ESP); and / or at least one wired information display node connected to the signal generator through a circuit is installed on the vehicle, preferably in the cab, the wired information display node comprising a controller and built-in corresponding software for processing electrical signals and voltages from the signal generator; the wired information display node determines and displays the wheel number and corresponding information about the pressure and / or temperature in the tire;And if necessary, information about the wheel number and its angular velocity is transmitted to other vehicle systems, such as ABS, ESP systems; when operating a passive wired information display node (not containing an electrical energy source and not connected to the electrical system of the vehicle), the power supply of the passive wired information display node is performed by an electrical signal and / or voltage of a signal generator; and the passive wired information display node may contain at least one battery electrical energy storage device, and / or at least one capacitor, and wherein all information display nodes may be combined in at least one block.; 2. The passive measuring instrument according to claim 1, characterized in that: at least one pressure sensor comprises at least one coil inductor and at least one electrical device, the electrical device is preferably a resistor, the resistance of the resistor depends on the air pressure in the tire, wherein the at least one inductor coil and the at least one electrical device together form at least one circuit; and / or at least one temperature sensor comprises at least one coil inductor and at least one electrical device, the electrical device is preferably a resistor; The resistance of the resistor depends on the temperature of the air in the tire; wherein the at least one inductor forms at least one circuit with the at least one electrical device; and wherein the at least one pressure sensor and / or the at least one temperature sensor are combined in at least one unit.

3. The passive measuring instrument according to claim 2, characterized in that: At least one coil inductor is made in the form of a loop of wire with a cross-section of any shape and size, such as rectangular, circular, oval or other shape, and / or in the form of a cut washer, and / or in the form of a cut ring, and / or in the form of a disk cut along the radius of at least one coil inductor, and is made of non-magnetic conductive material.

4. The passive measuring instrument according to claim 1, characterized in that: The signal generator comprises at least one permanent magnet of arbitrary shape and / or at least one electromagnet of arbitrary shape, and at least one coil inductor of arbitrary shape; wherein the at least one inductor coil is located near at least one permanent magnet of arbitrary shape and / or near at least one electromagnet of arbitrary shape, and / or is installed on at least one permanent magnet of arbitrary shape and / or at least one electromagnet of arbitrary shape.

5. The passive measuring instrument according to claim 1, characterized in that: At least one signal generator is composed of a cylindrical permanent magnet and a circular coil inductor located at the end of the cylindrical permanent magnet; wherein, in order to install the signal generator near the inner surface of the rim and / or the outer surface of the tire, the signal generator is located on a bracket installed near the vehicle wheel, preferably at the other end of the cylindrical permanent magnet.

6. The passive measuring instrument according to claim 1, characterized in that: The wheel number and the corresponding information about the pressure and / or temperature in the tire are displayed by means of appropriate light and / or acoustic signals.

7. The passive pressure gauge according to claim 1, characterized in that: At least one pressure sensor and / or at least one temperature sensor and / or at least one structural element are mounted on the tire during tire manufacturing.

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