Automatic tire inflation and deflation apparatus and method

Abstract

Disclosed in the invention are an automatic tire inflation and deflation apparatus and method. Inflation and deflation control can be achieved using one electromagnetic pneumatic valve and one pipe. The internal pressure in the tire and time are detected by 2-3 times of pauses. The pressure in the tire at any time point in the future is calculated by means of a mathematical method, such that the pressure displayed on an inflation and deflation device reflects the pressure in the tire in real time, such that automatic and accurate control of tire inflation and deflation is achieved, and the cost is low.

Description

Automatic tire inflation and deflation device and method Technical Field

[0001] The present invention relates to tire inflation and deflation, and in particular to an automatic tire inflation and deflation device and method. Background Art

[0002] Vehicles, especially off-road vehicles, need to deflate their tires when entering terrain such as deserts, gravel, mountains, mud, and snow to reduce the tire pressure, thereby increasing the contact area between the tire and the ground and increasing friction. In this case, the tire pressure can be reduced to 5-15psi, and when returning to normal roads, the tire pressure must be inflated to a normal value, usually 30-60psi. For large-flow inflation devices, due to the large pressure drop in the inflation pipeline, the pressure gauge on the inflation device cannot accurately reflect the pressure inside the tire. The usual practice is to manually control the pneumatic valve on the pipeline to stop inflation so that the pressure inside the tire can be accurately read. This may require many starts and stops to obtain the required accurate tire pressure. Patent application PCT / CN2023 / 088403 provides an air pump that accurately reflects the internal pressure of the tire through the pressure gauge on the air source equipment, thereby realizing the function of automatically shutting down the air pump at a preset pressure.

[0003] During tire deflation, the same problem exists due to the large air flow. Therefore, people also need a deflation device that can accurately reflect the pressure inside the tire, preset the deflation pressure, and automatically stop.

[0004] The existing technology for inflation and deflation devices that can achieve preset and automatic stop has the following problems: First, such inflation and deflation devices generally control inflation and deflation respectively through two air circuits, which is relatively expensive; second, during the inflation and deflation process, the pressure gauge cannot reflect the pressure inside the tire in real time, and needs to be started and stopped at fixed intervals multiple times. The pressure inside the tire can only be displayed when it stops, and it cannot display the pressure inside the tire in real time. Moreover, due to the fixed cycle of start and stop, it cannot ultimately stop accurately at the preset pressure value, resulting in large errors.

[0005] Summary of the Invention

[0006] In view of the above-mentioned deficiencies in the prior art, the present invention first provides an automatic tire inflation and deflation device, comprising an air pipe, one end of which can be connected to a tire and the other end of which can be connected to an air source or the atmosphere to inflate and deflate the tire; a pressure sensor, a solenoid valve, and a manual valve are sequentially provided on the air pipe starting from the end connected to the tire; the air pipe also includes a control unit and a power supply, the control unit being configured to receive pressure data from the pressure sensor and to control the opening and closing of the solenoid valve by controlling the power supply to turn on and off the solenoid valve;

[0007] When inflating a tire, one end of the air tube is connected to the tire and the other end is connected to the air source. In the initial state, the solenoid valve is open and the manual valve is closed. At the moment the manual valve is opened, the pressure sensor detects a sudden pressure increase signal. The control unit is configured to perform the following operations upon receiving the pressure increase signal: during the inflation process, the solenoid valve is intermittently closed three or more times, each time for 1-2 seconds, and then opened again. The control unit fits a function curve between the actual tire pressure P and the dynamic pressure P0 during the inflation process based on the detected static and dynamic tire pressure data. The actual tire pressure P is then calculated based on the dynamic pressure P0 detected by the pressure sensor. When the actual tire pressure reaches the preset target value, the solenoid valve is closed, ending inflation.

[0008] When the tire is deflated, one end of the air pipe is connected to the tire and the other end is directly connected to the atmosphere; in the initial state, the solenoid valve is open and the manual valve is closed; at the moment the manual valve is opened, the pressure sensor detects a sudden pressure drop signal, and the control unit is set to perform the following operations after receiving the pressure drop signal: during the deflation process, the solenoid valve is intermittently closed more than three times, each time for 1-2 seconds, and then the solenoid valve is opened again; the control unit fits the functional relationship curve between the actual tire pressure P and the dynamic pressure P0 based on the detected static and dynamic tire pressure data, and then calculates the actual tire pressure P based on the dynamic pressure P0 detected by the pressure sensor, and when the actual tire pressure reaches the preset target value, the solenoid valve is closed to end the deflation.

[0009] In a preferred embodiment of the present invention, the function curve of the actual tire pressure P and the dynamic pressure P0 during the inflation process is fitted into a quadratic curve, that is, the functional relationship is P=aP0 2 +bP0+c, the control unit is configured to substitute the detected static and dynamic tire pressure data into a functional relationship, calculate the coefficients a, b, and c, thereby determining the functional relationship, and calculating the actual tire pressure based on the functional relationship.

[0010] In another preferred embodiment of the present invention, the solenoid valve is a normally open solenoid valve.

[0011] In another preferred embodiment of the present invention, the control unit is further connected to a display unit for displaying the current pressure value.

[0012] The present invention provides a method for automatically inflating and deflation of a tire, comprising the steps of:

[0013] (1) An air pipe is provided, and a pressure sensor, a solenoid valve, and a manual valve are sequentially arranged on the air pipe from the end connected to the tire; a control unit is configured to receive pressure data from the pressure sensor and control the opening and closing of the solenoid valve by controlling the power supply to the solenoid valve;

[0014] (2) When inflating a tire, one end of the air pipe is connected to the tire and the other end is connected to the air source; in the initial state, the solenoid valve is open and the manual valve is closed; when the manual valve is opened, the pressure sensor detects a sudden pressure rise signal, and the control unit performs the following operations after receiving the pressure rise signal: during the inflation process, the solenoid valve is intermittently closed for more than three times, each time for 1-2 seconds, and then the solenoid valve is opened again; the control unit fits a function curve of the actual tire pressure P and the dynamic pressure P0 during the inflation process based on the detected static and dynamic tire pressure data, and then calculates the actual tire pressure P based on the dynamic pressure P0 detected by the pressure sensor, and when the actual tire pressure reaches the preset target value, the solenoid valve is closed to end the inflation;

[0015] (3) When deflating the tire, one end of the air pipe is connected to the tire and the other end is directly connected to the atmosphere; in the initial state, the solenoid valve is open and the manual valve is closed; when the manual valve is opened, the pressure sensor detects a sudden pressure drop signal, and the control unit is configured to perform the following operations upon receiving the pressure drop signal: during the deflation process, the solenoid valve is intermittently closed for more than three times, each time for 1-2 seconds, and then the solenoid valve is opened again; the control unit fits a quadratic curve of the functional relationship between the actual tire pressure P and the dynamic pressure P0 based on the detected static and dynamic tire pressure data, and then calculates the actual tire pressure P based on the dynamic pressure P0 detected by the pressure sensor, and when the actual tire pressure reaches the preset target value, the solenoid valve is closed to end the deflation.

[0016] In a preferred embodiment of the present invention, the function curve of the actual tire pressure P and the dynamic pressure P0 during the inflation process is fitted into a quadratic curve, that is, the functional relationship is P=aP0 2 +bP0+c, the control unit is configured to substitute the detected static and dynamic tire pressure data into a functional relationship, calculate the coefficients a, b, and c, thereby determining the functional relationship, and calculating the actual tire pressure based on the functional relationship.

[0017] In another preferred embodiment of the present invention, the solenoid valve is a normally open solenoid valve.

[0018] In another preferred embodiment of the present invention, the control unit is further connected to a display unit for displaying the current pressure value.

[0019] The automatic tire inflation and deflation device of the present invention uses a single electromagnetic pneumatic valve and a single pipeline to achieve low-cost control of inflation and deflation. By pausing for 2-3 times, the device detects the internal tire pressure and time, mathematically inferring the tire's internal pressure at any future time point. This ensures that the pressure displayed on the inflation and deflation device reflects the tire's internal pressure in real time, thereby achieving automatic and precise control of tire inflation and deflation.

[0020] The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG1 is a graph showing the relationship between the inflation and deflation pressures and the actual tire pressure function during the inflation process in a preferred embodiment of the present invention;

[0022] FIG2 is a block diagram showing the principle of an automatic tire inflation and deflation device in a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0023] The following describes several preferred embodiments of the present invention with reference to the accompanying drawings to make its technical content clearer and easier to understand. The present invention can be embodied in many different forms of embodiments, and the scope of protection of the present invention is not limited to the embodiments mentioned herein.

[0024] In the drawings, components with identical structures are denoted by the same reference numerals, and components with similar structures or functions are denoted by similar reference numerals. The size and thickness of each component shown in the drawings are arbitrary and are not limited by the present invention. For clarity, the thickness of components in some places in the drawings is appropriately exaggerated.

[0025] As shown in Figure 1, it was found through testing that when the tire is inflated or deflated, the relationship between the static pressure, i.e., the actual tire pressure P, and the dynamic pressure, i.e., the inflation and deflation pressure P0, is a quadratic curve, and its function expression is: P = aP0 2 +bP0+c (1)

[0026] For a quadratic function curve, the coefficients a, b, and c are determined by at least three points. Since the static pressure measured when inflation and deflation are stopped is consistent with the actual tire pressure, we can take a short pause in inflation and deflation to measure the actual tire pressure. As shown in Figure 2, the ordinate is the actual tire pressure P, and the abscissa is the inflation pressure P0. In this embodiment, the actual tire pressure P is measured at P and the horizontal axis is the inflation pressure P0. 01 、P 02 and P 03 Pause inflation at the three points for about one second. The pressures measured after stopping inflation and deflation are the actual pressures P1, P2, and P3 at each point. The pressure measured immediately before or after the pause at each point when inflation and deflation resume is the measured pressure P0 at that point. The measured and actual pressure values ​​for the three points in Figure 1 are shown in Table 1:

[0027] Table 1

[0028] Substituting the values ​​of the above three points into formula (1), we can obtain the functional relationship between the actual tire pressure P0 and the measured pressure P. In formula (2), the coefficients a = -0.0151, b = 3.3387, and c = 93.829 are obtained; then the functional relationship is: P = -0.0151P0 2 +3.3387P0-93.829

[0029] The function curve is shown as the dotted line in Figure 2. Thus, we can calculate the actual tire pressure at any moment based on the measured pressure, and use the actual pressure instead of the measured pressure for display or further control of the inflation process based on it.

[0030] In actual use, different tire sizes and different air tube lengths will affect the calculated values ​​of the a, b, and c coefficients of the functional relationship.

[0031] Of course, in other embodiments, multiple pauses can be used to further calibrate the parameters of the functional relationship for greater accuracy. In actual use, by adjusting the time interval between each brief pause, the error between the measured and actual tire pressure can be controlled within 2 psi, meaning the maximum deviation does not exceed 5% of the actual tire pressure.

[0032] As shown in Figure 2, in a specific embodiment of the automatic tire inflation and deflation device according to the present invention, the device includes an air pipe 7, one end of which can be connected to the tire and the other end can be connected to an air source or the atmosphere. Air pipe 7 is provided, starting from the end connected to the tire, with a pressure sensor 4, a solenoid valve 5, and a manual valve 6. In the embodiment shown in Figure 2, solenoid valve 5 is a normally open solenoid valve. The device also includes a control unit 1 and a power supply 3. Control unit 1 receives pressure data from pressure sensor 4 and controls the opening and closing of solenoid valve 5 by controlling the power supply 3 to turn on and off.

[0033] When inflating a tire, one end of the air tube 7 is connected to the tire, and the other end is connected to an air source, such as an air pump or air tank. In this embodiment, the solenoid valve 5 is a normally open type. Therefore, in its initial state, the solenoid valve 5 is open, while the manual valve 4 is closed. The pressure sensor 4 detects the pressure in the air tube and transmits it to the control unit 1. The moment the manual valve 4 opens, the pressure sensor 4 detects a sudden pressure increase signal. Upon receiving this pressure increase signal, the control unit 1 is configured to perform the following operations: during the inflation process, the solenoid valve 5 is intermittently closed three or more times, each time for 1-2 seconds, and then reopened. Based on the detected data, the control unit 1 fits a quadratic curve representing the functional relationship between the actual tire pressure P and the dynamic pressure P0. The actual tire pressure P is then calculated based on the dynamic pressure P0 detected by the pressure sensor 4. When the actual tire pressure reaches the preset target value, the solenoid valve 3 is closed, completing the inflation process.

[0034] When deflating a tire, one end of air pipe 7 is connected to the tire, while the other end is directly connected to the atmosphere. In this embodiment, solenoid valve 5 is a normally open solenoid valve. Therefore, in the initial state, solenoid valve 5 is open and manual valve 4 is closed. Pressure sensor 4 detects the pressure in the air pipe and transmits it to control unit 1. At the moment manual valve 4 is opened, pressure sensor 4 detects a sudden pressure drop signal. Upon receiving this pressure drop signal, control unit 1 is configured to perform the following operations: during the deflation process, solenoid valve 5 is intermittently closed three or more times, each time for 1-2 seconds, and then reopened. Based on the detected data, control unit 1 fits a quadratic curve representing the functional relationship between actual tire pressure P and dynamic pressure P0. The actual tire pressure P is then calculated based on the dynamic pressure P0 detected by pressure sensor 4. When the actual tire pressure reaches the preset target value, solenoid valve 3 is closed, completing deflation.

[0035] In a further embodiment, the control unit 1 is further connected to a display unit 2 for displaying the current pressure value.

[0036] The preferred embodiments of the present invention have been described in detail above. It should be understood that numerous modifications and variations based on the concepts of the present invention are possible without inventive effort by those skilled in the art. Therefore, any technical solution that can be derived by one skilled in the art through logical analysis, reasoning, or limited experimentation based on the concepts of the present invention and the prior art should be within the scope of protection defined by the claims.

Claims

1. A tire automatic inflation and deflation device, characterized in that: The invention comprises an air pipe, one end of which can be connected to a tire, and the other end of which can be connected to an air source or connected to the atmosphere to inflate and deflate the tire; a pressure sensor, a solenoid valve and a manual valve are arranged on the air pipe in sequence from the end connected to the tire; the invention also comprises a control unit and a power supply, the control unit is arranged to receive pressure data transmitted by the pressure sensor, and control the opening and closing of the solenoid valve by controlling the power supply to turn on and off the solenoid valve; When inflating a tire, one end of the air pipe is connected to the tire, and the other end is connected to the air source; in the initial state, the solenoid valve is open and the manual valve is closed; at the moment the manual valve is opened, the pressure sensor detects a sudden pressure rise signal, and the control unit is configured to perform the following operations upon receiving the pressure rise signal: during the inflation process, the solenoid valve is intermittently closed for more than three times, each time for 1-2 seconds, and then the solenoid valve is opened again; the control unit fits a function curve of the actual tire pressure P and the dynamic pressure P0 during the inflation process based on the detected static and dynamic tire pressure data, and thereafter calculates the actual tire pressure P based on the dynamic pressure P0 detected by the pressure sensor, and when the actual tire pressure reaches the preset target value, the solenoid valve is closed to end the inflation; When the tire is deflated, one end of the air pipe is connected to the tire and the other end is directly connected to the atmosphere; in the initial state, the solenoid valve is open and the manual valve is closed; at the moment the manual valve is opened, the pressure sensor detects a sudden pressure drop signal, and the control unit is configured to perform the following operations after receiving the pressure drop signal: during the deflation process, the solenoid valve is intermittently closed more than three times, each time for 1-2 seconds, and then the solenoid valve is opened again; the control unit fits a functional relationship curve between the actual tire pressure P and the dynamic pressure P0 based on the detected static and dynamic tire pressure data, and then calculates the actual tire pressure P based on the dynamic pressure P0 detected by the pressure sensor, and when the actual tire pressure reaches the preset target value, the solenoid valve is closed to end the deflation.

2. The automatic tire inflation and deflation device according to claim 1, wherein: The function curve of the actual tire pressure P and the dynamic pressure P0 during inflation is fitted as a quadratic curve, that is, the functional relationship is P = aP0 2 +bP0+c, the control unit is configured to substitute the detected static and dynamic tire pressure data into the functional relationship, calculate the coefficients a, b, c, thereby determining the functional relationship, and calculate the actual tire pressure based on the functional relationship.

3. The automatic tire inflation and deflation device according to claim 1, wherein: The solenoid valve is a normally open type solenoid valve.

4. The automatic tire inflation and deflation device according to claim 1, wherein: The control unit is also connected to a display unit for displaying the current pressure value.

5. A method for automatically inflating and deflation of a tire, characterized in that: Includes steps: (1) An air pipe is provided, and a pressure sensor, a solenoid valve, and a manual valve are sequentially arranged on the air pipe from one end connected to the tire; a control unit is configured to receive pressure data transmitted by the pressure sensor, and control the opening and closing of the solenoid valve by controlling the power supply to turn on and off the solenoid valve; (2) When inflating a tire, connect one end of the air hose to the tire and the other end to the air source. In the initial state, the solenoid valve is open and the manual valve is closed. When the manual valve is opened, the pressure sensor detects a sudden The control unit performs the following operations after receiving the pressure rise signal: during the inflation process, the solenoid valve is intermittently closed for more than three times, each time for 1-2 seconds, and then the solenoid valve is opened; the control unit fits the function curve of the actual tire pressure P and the dynamic pressure P0 during the inflation process according to the detected static and dynamic tire pressure data, and then calculates the actual tire pressure P according to the dynamic pressure P0 detected by the pressure sensor, and when the actual tire pressure reaches the preset target value, the solenoid valve is closed to end the inflation; (3) When deflating the tire, one end of the air pipe is connected to the tire and the other end is directly connected to the atmosphere; in the initial state, the solenoid valve is open and the manual valve is closed; when the manual valve is opened, the pressure sensor detects a sudden pressure drop signal, and the control unit is configured to perform the following operations upon receiving the pressure drop signal: during the deflation process, the solenoid valve is intermittently closed for more than three times, each time for 1-2 seconds, and then the solenoid valve is opened again; the control unit fits a quadratic curve of the functional relationship between the actual tire pressure P and the dynamic pressure P0 based on the detected static and dynamic tire pressure data, and then calculates the actual tire pressure P based on the dynamic pressure P0 detected by the pressure sensor, and when the actual tire pressure reaches the preset target value, the solenoid valve is closed to end the deflation.

6. The automatic tire inflation and deflation method according to claim 5, wherein: The function curve of the actual tire pressure P and the dynamic pressure P0 during inflation is fitted as a quadratic curve, that is, the functional relationship is P = aP0 2 +bP0+c, the control unit is configured to substitute the detected static and dynamic tire pressure data into the functional relationship, calculate the coefficients a, b, c, thereby determining the functional relationship, and calculate the actual tire pressure based on the functional relationship.

7. The automatic tire inflation and deflation method according to claim 5, wherein: The solenoid valve is a normally open type solenoid valve.

8. The automatic tire inflation and deflation method according to claim 1, wherein: The control unit is also connected to a display unit for displaying the current pressure value.

Images