A non-pneumatic tire with variable radius and its active rollover prevention method

Abstract

The present invention discloses a non-pneumatic tire with variable radius and its active anti-rollover method. The non-pneumatic tire includes a wheel hub, a hydraulic pump, a first solenoid valve, a second solenoid valve, a single-channel hydraulic rotary joint, N hydraulic spoke assemblies, and a tread. The hydraulic pump is fixed in the first cavity, and the first solenoid valve is arranged in the infusion channel. The N hydraulic spoke assemblies are arranged in one-to-one correspondence with the N spoke mounting cavities. The inner tube of the single-channel hydraulic rotary joint is connected to the input pipeline of the hydraulic pump through a flange, and the outer tube is connected to an external hydraulic tank pipeline through the second solenoid valve. The tread is sleeved outside the supporting surfaces of the N hydraulic spoke assemblies and is in interference fit with them. When preventing rollover, the radius of the inner tire of the present invention becomes smaller, and the center of gravity of the vehicle moves towards the inner side of the turning direction, reducing the risk of the vehicle generating centrifugal rollover and ensuring the driving safety of the vehicle during steering.

Description

Technical Field

[0001] The present invention belongs to the field of automobile tires, and particularly relates to a non-pneumatic tire with variable radius and an active anti-rollover method thereof. Background Art

[0002] Tires are one of the important components of automobiles. Currently, the commonly used automobile tires are mainly pneumatic tires, but pneumatic tires have fatal problems such as air leakage and blowout. Non-pneumatic tires remove the inflation structures such as the airtight layer and belt layer of pneumatic tires, reducing the probability of air leakage and blowout of automobile tires and greatly improving the safety during the driving of automobiles.

[0003] In the related technologies of currently variable radius tires, the variable radius of the tires is mainly to ensure the passability of the vehicle and the comfort during driving. There is little research on combining the variable radius of the tires with preventing vehicle rollover. However, if the vehicle passes through a curve at a high speed and the radius of the vehicle tires does not change or does not change appropriately, the vehicle is extremely prone to rollover accidents. Summary of the Invention

[0004] The object of this invention patent is: to design an active anti-rollover method, starting from the spoke structure of the non-pneumatic tire, combining a hydraulic spoke assembly and a hydraulic pump to control the change of the wheel radius, and by changing the radii of the two wheels on the inner side of the vehicle steering, making the vehicle center of gravity tilt towards the inner side of the steering to achieve the purpose of anti-rollover.

[0005] The present invention adopts the following technical solutions to solve the above technical problems:

[0006] A non-pneumatic tire with variable radius includes a wheel hub, a hydraulic pump, a first solenoid valve, a second solenoid valve, a single-channel hydraulic rotary joint, N hydraulic spoke assemblies, and a tread, where N is a natural number greater than or equal to 3;

[0007] The wheel hub is in a disc shape and has a first cavity at the center for installing the hydraulic pump; the wheel hub has a coaxial annular second cavity outside its first cavity, and the wheel hub is provided with an infusion channel for connecting the second cavity and the first cavity; the first solenoid valve is arranged in the infusion channel to control the on-off of the infusion channel;

[0008] The wheel hub is circumferentially and evenly provided with N spoke installation cavities between its outer wall and the second cavity; the spoke installation cavity is in a cylindrical shape, and its axis points to the center of the wheel hub; the wheel hub is provided with a through hole connecting the spoke installation cavity and the outside at the outer end of each spoke installation cavity and a through hole connecting the spoke installation cavity and the second cavity at the inner end;

[0009] The N hydraulic spoke assemblies are arranged in one-to-one correspondence with the N spoke installation cavities;

[0010] The hydraulic spoke assembly includes a support surface, a connecting portion, a spoke rod, a first spring, and a second spring. Among them, the support surface is an arc surface, and its outer wall is used to abut against the inner wall of the tread to support the tread; one end of the connecting portion is fixedly connected to the center of the inner wall of the support surface, and the other end is fixedly connected to one end of the spoke rod; the other end of the spoke rod extends into the through hole outside the corresponding spoke mounting cavity, and a piston that is hermetically fitted with the spoke mounting cavity is provided at the end of the spoke rod, so that the spoke rod can freely slide along its corresponding spoke mounting cavity; the first spring is sleeved on the spoke rod, one end abuts against the piston, and the other end abuts against the hub at the outer through hole of the spoke rod corresponding to the spoke mounting cavity; the second spring is arranged in the spoke mounting cavity corresponding to the spoke rod, one end abuts against the piston, and the other end abuts against the hub at the inner through hole of the spoke rod corresponding to the spoke mounting cavity;

[0011] The hydraulic pump is fixed in the first cavity, and its output end is hermetically connected to the infusion channel through a pipeline;

[0012] An installation hole for installing the single-channel hydraulic rotary joint is provided at the center of the inner end wall of the hub; the single-channel hydraulic rotary joint is a flange-connected, inner-tube rotary type hydraulic rotary joint, and its inner tube is connected to the input pipeline of the hydraulic pump through a flange, and the outer tube is connected to the external hydraulic tank pipeline through the second solenoid valve; the second solenoid valve is used to control the on-off between the external hydraulic tank and the outer tube of the single-channel hydraulic rotary joint;

[0013] The tread is made of a flexible material and is sleeved outside the support surfaces of the N hydraulic spoke assemblies and is in interference fit with them.

[0014] As a further optimized solution of the non-pneumatic tire with variable radius of the present invention, the tread is made of rubber.

[0015] As a further optimized solution of the non-pneumatic tire with variable radius of the present invention, a plurality of protrusions are evenly provided on the outer wall of the support surface to increase the friction force between the support surface and the inner wall of the tread.

[0016] The present invention also discloses an active anti-rollover method for an automobile using the non-pneumatic tire with variable radius. The automobile uses front-wheel steering, and all four wheels of the automobile use non-pneumatic tires with variable radius. The active anti-rollover method for the automobile includes the following steps:

[0017] Step 1), detect the vertical forces of the four tires of the automobile, and calculate the value LTR representing the roll degree of the automobile according to the following formula:

[0018]

[0019] Among them, F Z1 represents the vertical force of the left front wheel of the automobile, F Z2represents the vertical force of the right front wheel of the vehicle, F Z3 represents the vertical force of the left rear wheel of the vehicle, F Z4 represents the vertical force of the right rear wheel of the vehicle; LTR ∈ [-1, 1], the closer it is to ±1, the greater the risk of the vehicle rolling or even tipping over;

[0020] Step 2), compare the absolute value of LTR with the preset roll threshold LTR th for comparison;

[0021] Step 2.1), if the absolute value of LTR is greater than or equal to LTR th :

[0022] Step 2.1.1), record the steering direction and steering angle information of the steering wheel during the entire steering period, and record the steering angle information at the current moment in an accumulative form. Calculate the real-time front wheel angle according to the steering ratio between the steering wheel and the steering wheel; if the steering angle information at the current moment is the angle of turning to the left, control the hydraulic pumps of the two wheels on the right side of the vehicle to stop working; if the steering angle information at the current moment is the angle of turning to the right, control the hydraulic pumps of the two wheels on the left side of the vehicle to stop working;

[0023] Step 2.1.2), calculate the centrifugal force of the vehicle at the bend according to the following formula:

[0024]

[0025] where, F c is the centrifugal force of the vehicle; m is the mass of the whole vehicle; v is the vehicle speed; R is the turning radius; L is the wheelbase of the vehicle; δ is the front wheel angle;

[0026] Step 2.1.3), calculate the target diameter h of the two inner tires of the vehicle according to the following formula:

[0027]

[0028] where, g is the acceleration due to gravity; α is the roll angle of the vehicle; B is the equivalent wheelbase;

[0029] Step 2.1.4), calculate the volume of the discharged liquid V required for the N hydraulic spoke assemblies in the two inner tires of the vehicle to move a displacement of h / 2 according to the bottom area of the spoke mounting cavity. Control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to open, and control the hydraulic pumps in the two inner tires of the vehicle to work until the volume of the discharged liquid of the N hydraulic spoke assemblies in the two inner tires of the vehicle is V. At this time, control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to close, and control the hydraulic pumps in the two inner tires of the vehicle to stop working;

[0030] Step 2.2), when the absolute value of LTR is less than LTR th control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to open, and control the hydraulic pump in the two inner tires of the vehicle to work until the tire radius is restored. At this time, control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to close, and control the hydraulic pump in the two inner tires of the vehicle to stop working.

[0031] Compared with the prior art, the present invention adopts the above technical solutions and has the following technical effects:

[0032] 1. The tire of the present invention includes a wheel hub, a hydraulic pump, a first solenoid valve, a second solenoid valve, a single-channel hydraulic rotary joint, N hydraulic spoke assemblies, and a tread. The wheel hub is highly integrated, with several installation cavities and installation holes provided on the wheel hub, and a first cavity for installing the hydraulic pump is provided at the center of the wheel hub; N spoke installation cavities are evenly provided circumferentially between the outer wall of the wheel hub and the second cavity; an installation hole for installing the single-channel hydraulic rotary joint is provided at the center of the inner end wall of the wheel hub.

[0033] 2. The connecting part and the supporting surface of the hydraulic spoke assembly in the present invention are of a hollow structure, which reduces the weight of the tire and improves the working environment of the spoke rod in the hydraulic spoke assembly; the protrusions on the supporting surface can increase the friction between the supporting surface and the tread, prevent the spoke assembly from slipping inside the tread, and improve the driving safety.

[0034] 3. The interior of the hydraulic spoke assembly of the present invention is provided with a first spring and a second spring. When the tire travels on a complex road surface, it can effectively relieve the impact of the road surface on the first solenoid valve and improve the service life of the system.

[0035] 4. The half shaft of the vehicle in the present invention is fixedly connected to the vehicle body through a hydraulic mechanism. When the vehicle turns in a curve, the diameter of the two inner tires on the turning side can be reduced, so that the vehicle body and the half shaft tilt together towards the side where the tires are reduced; the inner tilt in the curve can reduce the required ground lateral force, tilt the vehicle center of gravity towards the inner side of the turn, and reduce the risk of the vehicle rolling over centrifugally. Description of the Drawings

[0036] Figure 1 is the front view of the structure of the present invention;

[0037] Figure 2 is the front view of the structure of a single hydraulic spoke assembly of the present invention;

[0038] Figure 3 is the left view of the internal part structure of the wheel of the present invention;

[0039] Figure 4 is the schematic diagram of the vehicle tilting and turning of the present invention;

[0040] Figure 5 Flow chart of the control method of the present invention;

[0041] Figure 6 Schematic diagram of the state comparison before and after the radius reduction of the present invention.

[0042] In the figure, 1 - tread, 2 - wheel hub, 3 - first solenoid valve, 4 - infusion channel, 5 - hydraulic pump, 6 - hydraulic spoke assembly, 7 - support surface, 8 - connecting rod part, 9 - spoke rod, 10 - first spring, 11 - piston, 12 - second spring, 13 - inner tube of the single - channel hydraulic rotary joint, 14 - outer tube of the single - channel hydraulic rotary joint, 15 - second solenoid valve, 16 - pipeline. Specific embodiments

[0043] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings:

[0044] As Figure 1 shown, the present invention discloses a non - pneumatic tire with variable radius and its active anti - rollover method, including: a wheel hub, a hydraulic pump, a first solenoid valve, a second solenoid valve, a single - channel hydraulic rotary joint, a hydraulic controller, N hydraulic actuators, N spokes, and a tread, where N is a natural number greater than or equal to 3;

[0045] The wheel hub is in a disc shape, and a first cavity for installing the hydraulic pump is provided at the center; an annular second cavity coaxial with the wheel hub is provided outside the first cavity of the wheel hub, and an infusion channel for connecting the second cavity and the first cavity is provided inside the wheel hub; the first solenoid valve is arranged in the infusion channel to control the on - off of the infusion channel;

[0046] N spoke mounting cavities are circumferentially and evenly provided between the outer wall of the wheel hub and the second cavity; the spoke mounting cavity is in a cylindrical shape, and its axis points to the center of the wheel hub; the wheel hub is provided with a through - hole connecting the spoke mounting cavity and the outside at the outer end of each spoke mounting cavity and a through - hole connecting the spoke mounting cavity and the second cavity at the inner end;

[0047] As Figure 2As shown, the hydraulic spoke assembly includes a support surface, a connecting portion, a spoke rod, a first spring, and a second spring. Among them, the support surface is an arc surface, and its outer wall is used to abut against the inner wall of the tread to support the tread; one end of the connecting portion is fixedly connected to the center of the inner wall of the support surface, and the other end is fixedly connected to one end of the spoke rod; the other end of the spoke rod extends into the through hole outside the corresponding spoke mounting cavity, and a piston that is hermetically fitted with the spoke mounting cavity is provided at the end of the spoke rod, so that the spoke rod can slide freely along its corresponding spoke mounting cavity; the first spring is sleeved on the spoke rod, one end abuts against the piston, and the other end abuts against the hub at the outside through hole of the spoke rod corresponding to the spoke mounting cavity; the second spring is arranged in the spoke mounting cavity corresponding to the spoke rod, one end abuts against the piston, and the other end abuts against the hub at the inside through hole of the spoke rod corresponding to the spoke mounting cavity; a plurality of protrusions are uniformly provided on the outer wall of the support surface to increase the friction force between the support surface and the inner wall of the tread;

[0048] As Figure 3 shown, the hydraulic pump is fixed in the first cavity, and its output end is hermetically connected to the infusion channel through a pipeline; an installation hole for installing the single-channel hydraulic rotary joint is provided at the center of the inner end wall of the hub; the single-channel hydraulic rotary joint is a flange-connected and inner-tube rotary hydraulic rotary joint, its inner tube is connected to the input pipeline of the hydraulic pump through a flange, and the outer tube is connected to the external hydraulic tank pipeline through the second solenoid valve; the second solenoid valve is used to control the on-off between the external hydraulic tank and the outer tube of the single-channel hydraulic rotary joint;

[0049] As Figure 4 shown, the half shaft of the vehicle is fixedly connected to the vehicle body through a hydraulic mechanism. When the vehicle turns in a curve, the diameters of the two tires on the inner side of the turn can be reduced, so that the vehicle body and the half shaft tilt together towards the side where the tires are reduced; the inner inclination of the curve can reduce the required ground lateral force, and the vehicle center of gravity tilts towards the inner side of the turn to achieve the purpose of anti-rollover;

[0050] As Figure 5 shown, the present invention also discloses an active anti-rollover method for an automobile with the non-pneumatic tire having a variable radius. The automobile uses front-wheel steering, and all four wheels of the automobile use non-pneumatic tires with a variable radius. The active anti-rollover method for the automobile includes the following steps:

[0051] Step 1), detect the vertical forces of the four tires of the automobile, and calculate the value LTR representing the roll degree of the automobile according to the following formula:

[0052]

[0053] where, F Z1 represents the vertical force of the left front wheel of the automobile, F Z2 represents the vertical force of the right front wheel of the automobile, FZ3 represents the vertical force of the left rear wheel of the vehicle, F Z4 represents the vertical force of the right rear wheel of the vehicle; LTR ∈ [-1, 1], the closer it is to ±1, the greater the risk of the vehicle rolling or even tipping over;

[0054] Step 2), compare the absolute value of LTR with the preset roll threshold LTR th for comparison;

[0055] Step 2.1), if the absolute value of LTR is greater than or equal to LTR th :

[0056] Step 2.1.1), record the steering direction and steering angle information of the steering wheel during the entire steering period, and record the steering angle information at the current moment in an accumulative form. Calculate the real-time front wheel angle according to the steering ratio between the steering wheel and the steering wheel; if the steering angle information at the current moment is the angle of turning to the left, control the hydraulic pumps of the two wheels on the right side of the vehicle to stop working; if the steering angle information at the current moment is the angle of turning to the right, control the hydraulic pumps of the two wheels on the left side of the vehicle to stop working;

[0057] Step 2.1.2), calculate the centrifugal force of the vehicle at the bend according to the following formula:

[0058]

[0059] where, F c is the centrifugal force of the vehicle; m is the total vehicle mass; v is the vehicle speed; R is the turning radius; L is the wheelbase of the vehicle; δ is the front wheel angle;

[0060] Step 2.1.3), calculate the target diameter h of the two inner tires of the vehicle according to the following formula:

[0061]

[0062] where, g is the acceleration due to gravity; α is the roll angle of the vehicle; B is the equivalent wheelbase;

[0063] Step 2.1.4), calculate the volume of the liquid discharged required for the N hydraulic spoke assemblies in the two inner tires of the vehicle to move a displacement of h / 2 according to the bottom area of the spoke mounting cavity. Control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to open and control the hydraulic pumps in the two inner tires of the vehicle to work until the volume of the liquid discharged by the N hydraulic spoke assemblies in the two inner tires of the vehicle is V. At this time, control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to close and control the hydraulic pumps in the two inner tires of the vehicle to stop working. The comparison of the front and rear states of the wheels is as Figure 6 shown;

[0064] Step 2.2), when the absolute value of the LTR is less than the LTR th control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to open, and control the hydraulic pump in the two inner tires of the vehicle to operate until the tire radius is restored. At this time, control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to close, and control the hydraulic pump in the two inner tires of the vehicle to stop operating.

[0065] Those skilled in the art of this technology can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used here have the same meaning as the general understanding of those of ordinary skill in the art to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and will not be interpreted in an idealized or overly formal sense unless defined as here.

[0066] The specific embodiments described above have further elaborated on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A non-pneumatic tire with variable radius, characterized in that, It includes a wheel hub, a hydraulic pump, a first solenoid valve, a second solenoid valve, a single-channel hydraulic rotary joint, N hydraulic spoke assemblies, and a tread, where N is a natural number greater than or equal to 3; The wheel hub is disc-shaped and has a first cavity at the center for installing the hydraulic pump; The wheel hub has a coaxial annular second cavity outside its first cavity, and an infusion channel for connecting the second cavity and the first cavity is provided inside the wheel hub; the first solenoid valve is arranged in the infusion channel to control the on-off of the infusion channel; N spoke mounting cavities are circumferentially and evenly provided between the outer wall of the wheel hub and the second cavity; the spoke mounting cavity is cylindrical and its axis points to the center of the wheel hub; the wheel hub has a through hole connecting the spoke mounting cavity and the outside at the outer end of each spoke mounting cavity and a through hole connecting the spoke mounting cavity and the second cavity at the inner end; The N hydraulic spoke assemblies are arranged in one-to-one correspondence with the N spoke mounting cavities; The hydraulic spoke assembly includes a support surface, a connecting part, a spoke rod, a first spring and a second spring. Among them, the support surface is arc-shaped, and its outer wall is used to abut against the inner wall of the tread to support the tread; one end of the connecting part is fixedly connected to the center of the inner wall of the support surface, and the other end is fixedly connected to one end of the spoke rod; the other end of the spoke rod extends into the through hole outside its corresponding spoke mounting cavity, and a piston that is hermetically matched with the spoke mounting cavity is provided at the end of the spoke rod, so that the spoke rod can slide freely along its corresponding spoke mounting cavity; the first spring is sleeved on the spoke rod, one end abuts against the piston, and the other end abuts against the wheel hub at the outside through hole of the spoke mounting cavity corresponding to the spoke rod; the second spring is arranged in the spoke mounting cavity corresponding to the spoke rod, one end abuts against the piston, and the other end abuts against the wheel hub at the inside through hole of the spoke mounting cavity corresponding to the spoke rod; The hydraulic pump is fixed in the first cavity, and its output end is hermetically connected to the infusion channel through a pipeline; An installation hole for installing the single-channel hydraulic rotary joint is provided at the center of the inner end wall of the wheel hub; the single-channel hydraulic rotary joint is a flange-connected and inner-tube-rotating type hydraulic rotary joint, its inner tube is connected to the input pipeline of the hydraulic pump through a flange, and its outer tube is connected to an external hydraulic tank through the second solenoid valve; the second solenoid valve is used to control the on-off between the external hydraulic tank and the outer tube of the single-channel hydraulic rotary joint; The tread is made of a flexible material and is sleeved outside the support surfaces of the N hydraulic spoke assemblies and is in interference fit with them.

2. The non-pneumatic tire with variable radius according to claim 1, characterized in that, The tread is made of rubber.

3. The non-pneumatic tire with variable radius according to claim 1, characterized in that, A number of protrusions are evenly provided on the outer wall of the support surface to increase the friction force between the support surface and the inner wall of the tread.

4. An active rollover prevention method for an automobile based on the non-pneumatic tire with variable radius according to claim 1, the automobile uses front-wheel steering, and all four wheels of the automobile use non-pneumatic tires with variable radius, characterized in that, It includes the following steps: Step 1), detect the vertical forces of the four tires of the vehicle, and calculate the value LTR representing the roll degree of the vehicle according to the following formula: Among them, F Z1 represents the vertical force of the left front wheel of the vehicle, F Z2 represents the vertical force of the right front wheel of the vehicle, F Z3 represents the vertical force of the left rear wheel of the vehicle, F Z4 represents the vertical force of the right rear wheel of the vehicle; LTR ∈ [-1, 1], the closer it is to ±1, the greater the risk of vehicle roll or even rollover; Step 2), compare the absolute value of the LTR with a preset roll threshold LTR th for comparison; Step 2.1), if the absolute value of the LTR is greater than or equal to the LTR th : Step 2.1.1), record the steering direction and steering angle information of the steering wheel during the entire steering period, and record the steering angle information at the current moment in an accumulative form, and calculate the real-time front wheel steering angle according to the steering ratio between the steering wheel and the steering wheel; if the steering angle information of the steering wheel at the current moment is the angle of turning to the left, then control the hydraulic pumps of the two wheels on the right side of the vehicle to stop working; if the steering angle information of the steering wheel at the current moment is the angle of turning to the right, then control the hydraulic pumps of the two wheels on the left side of the vehicle to stop working; Step 2.1.2), calculate the centrifugal force of the vehicle at the bend according to the following formula: Among them, F c is the centrifugal force of the vehicle; m is the total vehicle mass; v is the vehicle speed; R is the turning radius; L is the wheelbase of the vehicle; δ is the front wheel angle; Step 2.1.3), calculate the target diameter h of the two inner tires of the vehicle according to the following formula: where, g is the acceleration due to gravity; α is the roll angle of the vehicle; B is the equivalent wheelbase; Step 2.1.4), calculate the volume V of the liquid discharged required for the N hydraulic spoke assemblies in the two inner tires of the vehicle to move a displacement of h / 2 according to the bottom area of the spoke mounting cavity, control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to open, and control the hydraulic pumps in the two inner tires of the vehicle to work until the volume of the liquid discharged by the N hydraulic spoke assemblies in the two inner tires of the vehicle is V. At this time, control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to close, and control the hydraulic pumps in the two inner tires of the vehicle to stop working; Step 2.2), when the absolute value of the LTR is less than the LTR th control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to open, and control the hydraulic pump in the two inner tires of the vehicle to work until the tire radius is restored. At this time, control the first solenoid valve and the second solenoid valve in the two inner tires of the vehicle to close, and control the hydraulic pump in the two inner tires of the vehicle to stop working.

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