GB2538570A

GB2538570A - Tyre pressure regulation

Info

Publication number: GB2538570A
Application number: GB1508935.2A
Authority: GB
Inventors: Joss Matthew
Original assignee: Energy Technologies Institute LLP
Current assignee: Energy Technologies Institute LLP
Priority date: 2015-05-22
Filing date: 2015-05-22
Publication date: 2016-11-23
Anticipated expiration: 2035-05-22
Also published as: WO2016189273A1; GB201508935D0; GB2538570B

Abstract

A tyre pressure regulation and management system, in which the tyre pressure is actively maintained from a high pressure source wherein the tyre is configured by having a low pressure storage area (8) containing a gas, a high pressure storage area (7) containing a gas that is at a higher pressure to the gas stored in the low pressure storage area (8) and a means for exchanging gas (5) between the high and low pressure store so as to alter the pressure of the tyre.

Description

Tyre Pressure Regulation

Field of the Invention

[1] This invention relates to a tyre and to a pressure regulation and management system for use therewith.

Background

[2] Inflatable vehicle wheel tyres perform differently depending on their level of inflation. At one extreme, a flat tyre will perform badly and perhaps dangerously. At the other, an over-inflated tyre may have insufficient grip. Further, different rolling surfaces require different levels of inflation. On a good road surface, a higher pressure may be preferred, in order to reduce friction and therefore required power, and consequently required fuel, and engine emissions produced. On a bad surface, lower pressure may give a better grip. Heavy Duty Vehicles (agricultural vehicles, construction vehicles and heavy trucks or lorries) may cross from one surface to another several times during a day. The appropriate pressure specified by the tyre manufacturer in such cases is a sub-optimal compromise between those appropriate for different surfaces.

[3] Various systems are known which vary the tyre pressure, for different purposes.

For example, EP1989063, DE102013005577 and US5679187 have a high pressure reservoir connectable to the tyre for controllably inflating it. The reservoir is built into the metal wheel itself.

[004] Other systems aim to vary the profile of the tyre. For example, US2013153082 has an inflatable pressure reservoir located in the tyre face but isolated from the tyre, which can be expanded to change the tyre profile. Similarly, DE3919710 and CH542732 change the tyre profile depending on road surface, in order to bring out claws to grip an icy road.

[005] US2013153082 discloses a system that enables a variable friction tyre. The system includes a primary inflatable tube that is at least partially encapsulated by the tyre wall portion, and a secondary inflatable tube disposed between at least a portion of the tread portion and at least a portion of the primary inflatable tube. The secondary inflatable tube can selectively inflate or deflate in order to vary the amount of the tread portion in contact with the ground.

Summary of the Invention

[6] The invention relates to a tyre pressure regulation system with high and low pressure stores situated within a vehicle tyre.

[7] The tyre pressure regulation and management system described herein proposes to solve the problem associated with the need for operating a tyre at different tyre pressures when travelling on different road surfaces, in changing weather conditions and/or when the operating load of the vehicle changes.

[8] The tyre pressure regulation and management system described in this description can alter the pressure of the tyre by dynamically varying the pressure between the high and low pressure stores located within the tyre. Therefore, the tyre pressure regulation system enables for the pressure within a tyre to be adjusted to suit the road surface and improve traction.

[9] This is advantageous as adjusting the pressure of the tyre to suit the road surface has the effect of optimising the rolling resistance of the tyre, thus improving the fuel economy of the vehicle and reducing vehicle energy losses. The tyre pressure regulation system can attribute up to a 16% improvement in fuel efficiency.

[0010] The tyre pressure regulation and management system with high and low pressure stores within a vehicle tyre as described herein, has the further advantages of improving the tyre structural stiffness and integrity under transient conditions such as explosive deflation.

[0011] The system can also be manufactured using methods and constructions already known to the art, therefore the system can be fully integrated and retro-fitted with most vehicles on the market.

[0012] As tyre manufacturing processes that are known in the art are used to manufacture the tyre pressure regulation system, there are minimal additional manufacturing costs associated to the manufacture of a tyre containing the tyre pressure regulation system.

[0013] As the tyre pressure regulation system is contained within the tyre, the tyre can also be reliably assembled under service conditions.

[0014] A further advantage of the tyre pressure regulation and management system with high and low pressure stores within the tyre, is that the tyre can be repaired in similar means to standard tyre constructions. In addition, because the tyre is constructed in a similar way to conventional tyres it can be re-treaded using methods known in the art, therefore, the lifetime of the tyre's operability can be extended.

[0015] Therefore, the tyre pressure regulation system described herein provides for a tyre that can improve fuel economy and limit environmental impacts, whilst not being greatly more expensive than a conventional tyre.

[0016] The tyre pressure regulation and management system with high and low pressure stores located within the tyre as described herein, has a further advantage of enabling the driver of the vehicle to continue driving should the outer tread of the tyre experience a failure.

[0017] These features of the tyre pressure regulation system are of particular benefit to heavy duty/heavy goods vehicles. Where vehicles, such as tractors, quarry vehicles and general Heavy Goods Vehicles often operate on a multitude of road surfaces and varying loads during the same journey. The system could therefore be employed within the tyres of such vehicles to enable the dynamic variation of tyre pressure to suit the road surface and/or carry load.

[0018] In addition, each of these vehicles also operates with differing rolling resistance, as such the ability to alter the pressure within the tyre to optimise this value is extremely beneficial and cost effective to the vehicle owner.

[0019] Although the tyre pressure regulation system disclosed within this description is suitable for heavy duty/heavy goods vehicles, it is also suitable for any vehicle that uses a pneumatic tyre.

Brief description of the Drawings

[0020] There now follows, by way of example only, a detailed description of embodiments of the present invention, with reference to the figures identified below.

Figure 1 is a cross sectional representation of a wheel and tyre incorporating the tyre pressure regulation and management system with high and low pressure stores.

Figure 2 is a schematic representation of the gas exchange means and gas inlet/outlet pipe system of the tyre pressure regulation system.

Figure 3a is a schematic representation of the gas exchange means and gas inlet/outlet pipe when operating to lower the pressure within the tyre.

Figure 3b is a schematic representation of the gas exchange means and gas inlet/outlet pipe when operating to increase pressure within the tyre.

Figure 3c is a schematic representation of the gas exchange means and gas inlet/outlet pipe when operating to refill the high pressure store.

Figure 4 is a schematic representation of a vehicle containing the tyre pressure regulation and management system.

Detailed Description of the Embodiments

[0021] Figure 1 is a cross section schematic of a wheel and tyre configured by having high and low pressure stores located within the tyre. The tyre pressure regulation system comprises the following features: a wheel 1, a standard tyre profile 2, a reinforced high-pressure side wall 3, an internal dividing wall 4 internal to the tyre structure that separates the low and high pressure sections, an inlet and outlet tube 5 to provide a wheel-mounted control valve, an air pressure control block 6, a high pressure storage area 7 and a low pressure storage area 8.

[0022] The tyre pressure regulation system is configured by having a high pressure storage area 7 and a low pressure storage area 8 located inside the cavity of a tyre 2.

[0023] The side wall 3 is visually the same as a standard tyre, however it preferably has increased rigidity. The rigidity could be increased by using a side wall 3 that is thicker than that of a standard tyre, and/or by incorporating stiffening materials such as carbon or KevlarTM or steel into the wall 3 to reinforce the structural integrity of the tyre side wall 2, so that it maintains its shape when subject to the increased internal pressure.

[0024] In addition, the side wall 2 of the tyre could be thicker on the sides within the high pressure region 7, so that the tyre's internal structure maintains its shape and prevents bulging of the tyre 2.

[0025] The tyre pressure regulation system operates by having a high 7 pressure store located within the tyre, thus enables the pressure to be dynamically varied within the tyre by exchange of gas between the high pressure storage area 7 and low pressure storage area 8.

[0026] The ratio between the high pressure storage area 7 and low pressure storage area 8 can be varied between 10:1 and 1:1 depending on the application. Therefore, in a commercial vehicle, such as a Heavy Goods Vehicle, which has a normal operating tyre pressure in the region of 120psi, the high pressure region 7 within a tyre configured with the rolling resistance optimisation system could be in the region of 1200psi.

[0027] The high 7 and low 8 pressure storage areas are separated by an internal dividing wall 4. This internal wall 4 maintains the structural integrity of the high 7 and low 8 pressure storage areas, and maintains the pressure difference between the high 7 and low 8 pressure regions.

[0028] The internal wall 4 is further configured by a gas inlet/outlet tube 5 that enables the exchange of gas between the high pressure store 7 and low pressure store 8.

[0029] The inlet/outlet tube 5 is constructed from a material that ensures the structural integrity of the tube 5 during high pressure operation. The tube 5 will be constructed from a braided Steel, Carbon or KevlarTM material to ensure that the pipe maintains its rigidity and strength during installation, and the exchange of gas at high pressure.

[0030] Figure 2 is a schematic representation of the gas exchange means and the gas inlet/outlet pipe 5 system and the individual pipes contained within the inlet/outlet pipe system 5. The gas exchange means is configured by a gas inlet/outlet pipe 5, an exhaust valve 9 that vents gas to atmosphere, a plug mechanism to seal the pipe connecting to the low pressure store 11, a plug mechanism to seal the pipe connecting to the high pressure store 12 and a plug mechanism 13 sealing the exhaust valve 9. The gas inlet/outlet pipe 5 further comprises of a pipe connecting to the low pressure storage area 5a and a pipe connecting to the high pressure store 5b.

[0031] The inlet/outlet tube 5 consists of 2 ports, one for the exchanging gas from the low 8 to atmosphere via the control block 6, and one for the exchanging of gas from the high 7 to low 8 pressure store via the control block 6.

[0032] The tyre pressure regulation system enables the user to control the exchange of gas between the high 7 and low 8 pressure stores and the atmosphere. This process can either be instigated through manual control of the exhaust valve 9 located on the air pressure control block 6, or through an electronically controlled switch, located within the vehicle for ease of use, that can operate the process remotely. Conveniently the remote control is via a wireless link, for example a Radio Frequency (RF) link.

[0033] In the former case the vehicle is stationary for the gas exchange to take place. In the latter case, the user may operate the controlled switch from the dashboard on changing road surface. Alternatively, if suitable sensors are provided (such as pressure sensors and sensors to detect surface conditions, location and/or grade) a microprocessor or other control unit may determine from their output an optimum pressure, and control the control block 6 to attain it.

[0034] Figure 3a is a schematic representation of the gas exchange means and gas inlet/outlet pipe when operating in the deflation mode.

[0035] The tyre pressure regulation system operating in deflation mode enables the lowering of the pressure within the tyre.

[0036] To achieve lower pressure within the tyre, the plug mechanism 11 sealing the pipe connecting to the low pressure store 5a and the exhaust value 9 are opened. The exhaust valve 9 is opened by opening the plug mechanism 13. This enables the gas within the low pressure store to flow out of the tyre, thus lowering the pressure within the tyre.

[0037] The plug mechanism 11 and exhaust valve 9 remain open and let gas release from the tyre until the pressure within the tyre is lowered to the required value.

[0038] The pressure within the tyre is monitored by a pressure sensor 16. The pressure sensor can be any pressure monitoring system known in the art and can be located either within the tyre or in the control block able to detect pressures in both high 7 and low 8 pressure volumes.

[0039] Once the pressure within the high pressure volume 7 has reached the desired value, the plug mechanism 11 and the exhaust valve plug mechanism 13 are closed so as to stop the further release of gas out of the low pressure store.

[0040] Figure 3b is a schematic representation of the gas exchange means and gas inlet/outlet pipe when operating in the inflate mode.

[0041] The tyre pressure regulation system operating in the inflate mode enables for the pressure within the tyre to be increased.

[0042] To increase pressure within the tyre, the plug mechanism 11 sealing the pipe connecting the low pressure store 5a and the plug mechanism 12 sealing the pipe connecting the high pressure store 5b are opened. Opening the plug mechanism 12 sealing the high pressure store 7 allows the highly pressurised gas from within the high pressure store 7 to flow into the air pressure control block 6 and into the pipe connecting the low pressure store 5a.

[0043] The flow of gas from the high pressure store 7 into the pipe connecting the low pressure store 5a enables the pressure within the low pressure store 8 to be increased, thus further inflating the tyre.

[0044] The plug mechanisms 11,12 remain open; and allow gas to flow into the low pressure store 8 from the high pressure store 7, until the tyre pressure is increased to the desired value. Once the pressure reaches the desired value both plug mechanisms 11,12 are closed and seal the pressure stores.

[0045] Figure 3c is a schematic representation of the gas exchange means and the gas inlet/outlet pipe when operating in the refill mode.

[0046] Once the user has fully utilised the gas stored in the high pressure store 7 the user cannot further increase the pressure of the tyre. To overcome this issue, the tyre pressure regulation system allows for the high pressure store to be re-filled with highly pressurised gas [0047] To refill the high pressure store the user connects a pressurised gas container, such as those known in the art, to the exhaust valve 9 and insert high pressure gas into the high pressure storage area 7 within the tyre.

[0048] To allow the highly pressurised gas into the high pressure store 7 the exhaust valve 9 and the plug mechanism 13 sealing the exhaust valve 9 are opened, and the plug mechanism 12 sealing the pipe connecting the high pressure store 5b is also opened. This process opens the airway between the exhaust value 9 connected to the pressurised gas container and the high pressure store 7. Once the plug mechanisms 12,13 are opened, and a pressurised gas container is connected to the exhaust valve 9, pressurised gas can flow from the container into the high pressure store.

[0049] Once the high pressure store has been re-filled, the user can disconnect the pressurised gas container from the exhaust valve 9 and seal the gas within the tyre by closing the exhaust valve 9 and closing plug mechanisms 12,13. Once re-filled the tyre pressure regulation system can allow for the pressure within the tyre to be increased.

[0050] The plug mechanisms 11,12,13 are operated by a control device 10 located in the air pressure control block assembly 6. The control device 10 allows for the opening and closing of the plug mechanisms 11,12,13. When the user wishes to operate the tyre pressure regulation system to increase or decrease the pressure with the tyre, the motorised control device means 10a,10b,10c attached to the plug mechanisms 11,12,13, respectively, facilitate the opening and sealing of the pipes connecting the high and low pressure stores 5a, 5b and the exhaust valve 9 and thus initiate the inflate or deflate mode processes discussed above.

[0051] The control device 10 may further comprise a Radio Frequency (RF) or other wireless apparatus to enable the remote control operation of the opening and closing of the plug mechanisms via a wireless network.

[0052] The control device 10 is configured by means of an electrical actuator, such as a solenoid, attached to each of the plug mechanisms 11,12,13, which facilitates the opening and closing of the pipes 5a,5b and exhaust valve 9.

[0053] Figure 4 is a schematic representation of the vehicle containing the tyre pressure regulation and management system.

[0054] The tyre pressure management system 14 is located within the vehicle for ease of use for the user, however it could also be located on the wheel. The tyre pressure management system 14 comprises a user control interface 15 to enable user to select whether to increase or decrease the pressure within the tyre, a pressure sensor 16 to sense the pressure within the tyre, a sensor 17 to wirelessly exchange data with the pressure sensor 16 and a sensor 18 to wirelessly exchange data with the control device 10 located within the air pressure control block 6. The tyre pressure management system 14 enables the user to remotely operate the exchange of gas between the high and low pressure 7,8 stores from within the vehicle. This can either be at the users discretion or from an indication on the user control interface 15 that prompts the user to adjust the pressure of the tyre.

[0055] The user can remotely operate the exchange of gas within the tyre by pushing a button located on the user control interface 15. The user control interface displays to the driver of the vehicle the option to increase or decrease the pressure of the tyre. When the driver wishes to increase or decrease the pressure of the tyre, the driver pushes the respective button and begins the inflate or deflate mode. This data is then transferred to the control device 10 located in the air pressure control block 6 by the data exchange means 18. The data signal received by the control device 10 is then used to open or close the plug mechanisms 11,12 and allow for the exchange of gas between the pressure stores 7,8. The required pressure is determined by the tyre pressure management system 14. The system evaluates the pressure within the tyre by monitoring the values measured from the pressure sensor 16 and bases its determination of the desired pressure based on the road surface, weather conditions or load weight of the vehicle.

[0056] Once the tyre pressure management system 14 receives a pressure value from the pressure sensor 16 indicating that the pressure within the tyre is at the required value, the tyre pressure management system 14 system sends a signal to the control device 10 to close the respective plug mechanisms 11,12,13.

[0057] The driver of the vehicle may be alerted to the need to optimise the rolling resistance of the tyre through the measurements detected by the pressure sensor 16, which is also able to monitor the road surface the vehicle is travelling on, the associated load of the vehicle and/or the pressure within the tyre. The measurements from the sensor 16 would then trigger the alert on the user control interface 15 to notify the driver that the tyre pressure should be adjusted. The driver of the vehicle can then decide whether to alter the pressure within the tyre by interacting with the tyre pressure management system 14. This in turn enables the exchange of gas between the high 7 and low 8 pressure storage areas via the methods discussed above.

[0058] The wheel slip associated to the vehicle can also be measured and act as a further trigger to alert the driver of the vehicle to alter the tyre pressure.

[0059] The air pressure control block 6 containing the control device 10 and gas inlet/outlet pipe 5, is located on the wheel 1 at or near the existing wheel valve inlet, therefore a tyre fitted with the tyre pressure management system looks aesthetically like a conventional tyre.

[0060] The air pressure control block assembly 6 is bonded to the wheel using adhesive.

The air pressure control block assembly 6 is capable of withstanding inclement operating conditions and maintaining its structural integrity while operating in the high impact environment.

[0061] The air pressure control block 6 may also be configured to include a wireless remote control element, so as to enable the operation of the gas exchange from an electronically controlled switch located within the vehicle.

[0062] When the tyre pressure management system is in a passive mode, such that there is constant pressure, the exhaust valve 9 within the air pressure control block 6 enables the user to control the pressure within the tyre.

[0063] In a preferred embodiment of the invention the gas used in the high and low pressure stores 7,8 is air or Nitrogen, so as to avoid pollution when venting the gas to atmosphere.

[0064] In another preferred embodiment, the control devices 10a,106,10c are operated by solenoids so as to electrically control the opening and closing of the pipes Sa,Sb connecting the high and low pressure stores.

[0065] It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, * described in the context of a single embodiment, may also be provided separately or in any combination.

[0066] Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations.

Claims

Claims 1. A tyre comprising: a first region 8 within the tyre for containing a gas at a first pressure higher than atmospheric; a second region 7 for containing a gas at a second pressure higher than the first; and selectively connectable for supplying gas 5 to the first; characterised in that the second region 7 is located in the tyre.
2. A wheel comprising a tyre according to claim 1 and a tyre pressure regulation system comprising channels via which gas may be selectively routed to and from said second region 7.
3. A wheel according to claim 2, wherein the tyre pressure regulation system comprises: a first pipe 5b connecting to the second region 7; a second pipe 5a connecting to the first region 8; an exhaust valve 9 connected to the atmosphere; a first closure mechanism 12 to selectively close the first pipe; a second closure mechanism 11 to selectively close the second pipe; a third closure mechanism 13 to selectively close the exhaust valve 9; and a control device 10 for operating the closure mechanisms 11,12,13.
4. A tyre pressure management system comprising the wheel of claims 2 or 3, wherein the tyre pressure management system comprises: a control device 15; a pressure sensor 16 to sense pressure in the first and/or the second regions; and a data link (17,18) for communicating between the control device, the pressure sensor and the tyre pressure regulation system.
5. The system of claim 4, wherein the control device comprises a user control interface located within the vehicle.
6. The system of claim 5, wherein the user control interface 15 indicates to the user when to increase or decrease the pressure of the tyre.
7. The system of claim 5 or claim 6, wherein the user control interface 15 enables the user to command the increase or decrease of tyre pressure.
8. The system 14 of claim 4, wherein the data link is wireless.
9. The system 14 of claim 4, wherein when operating in inflate mode gas is routed from the second region 7 to the first region 8.
10. The system 14 of claim 4, wherein when operating in deflate mode the control device 10a allows the flow of gas from the first region 7 to atmosphere via the exhaust valve 13 so as to decrease the pressure within the tyre.
11. The system of claim 4, wherein when operating in refill mode the control device 10b allows high pressure gas from a connected external gas supply into the tyre to re-fill the second region 7.AMENDMENTS TO CLAIMS HAVE BEEN FILED AS FOLLOWS Claims 1. A tyre pressure regulation system comprising: a tyre having a cavity, the cavity having a first region for containing a gas at a first pressure higher than atmospheric and a second region for containing a gas at a second pressure higher than the first, wherein a side wall of the tyre is thicker in the second region than the first region; a first pipe connecting to the second region; a second pipe connecting to the first region; an exhaust valve adapted to vent gas to atmosphere; a first closure mechanism to selectively close the first pipe; a second closure mechanism to selectively close the second pipe; (r) a third closure mechanism to selectively close the exhaust valve; and a control device for operating the closure mechanisms and being operable to close (3) 15 the first closure and open the second and third closure when in a deflation mode.CO2. A tyre pressure regulation system of claim 1 further comprising: an internal wall, connected to the side wall, separating the cavity into the first and second regions.3. A tyre pressure regulation system of claim 1 or claim 2 further comprising a wheel, wherein the first pipe, the second pipe and the control device are located on the wheel.4. A tyre pressure regulation system of any preceding claim, wherein the first and second pipes and the exhaust valve are connected to a control block.5. A vehicle comprising the tyre pressure regulation system of any of claims 1 to 4 and a tyre pressure management system, wherein the tyre pressure management system comprises: a control interface; a pressure sensor to sense pressure in the first and/or the second regions; and a data link for communicating between the control device, the pressure sensor and the tyre pressure regulation system.6. The vehicle of claim 5, wherein the control interface comprises a user control interface located within the vehicle.7. The vehicle of claim 6, wherein the user control interface indicates to the user when to increase or decrease the pressure of the tyre.8. The vehicle of claim 6 or claim 7, wherein the user control interface enables the user to command the increase or decrease of tyre pressure.40) 15 9. The vehicle of claim 5, wherein the data link is wireless.CO10. The vehicle of claim 5, wherein when operating in inflate mode gas is routed from the second region to the first region.11. The vehicle of claim 5, wherein when operating in deflate mode the control device allows the flow of gas from the first region to atmosphere via the exhaust valve so as to decrease the pressure within the tyre.
12. The vehicle of claim 5, wherein when operating in refill mode the control device allows high pressure gas from a connected external gas supply into the tyre to re-fill the second region.