Device and method for testing tyres under imposed displacement in a controlled and cold environment

Abstract

The present invention relates to a test machine (100) comprising a self-supporting frame (1), a first and a second rotation hub (2, 3), a system (5) for adjusting the distance E between the centres of a first and a second tyre (10, 11) and at least one motor (4) for rotating and checking, simply and quickly, parameters such as the fatigue limit or the rolling resistance of the first and second tyres (10, 11). The present invention also relates to a controlled and cold environment test device (200) and to a method implementing the test machine (100) in a thermal vacuum chamber (20).

Description

Device and method for controlling tires under imposed displacement in a cold and controlled environment

[0001] The present invention relates to a tire testing machine and, in particular, a tire testing machine placed in a cold environment and under a controlled atmosphere, typically in an environment with a temperature that can go down to 40 K and in an atmosphere that can go up to a vacuum.

[0002] Conventional tire testing machines, also called "testing machines" or "rollers", allow the measurement of various parameters characterizing tires such as, for example, rolling resistance, uniformity or fatigue resistance also known as "endurance limit".

[0003] These tire testing machines typically consist of two main components: a rotating shaft to support a tire and a cylindrical flywheel with an outer or inner track that contacts the tire. A drive system, most often an electric or hydraulic motor, rotates the cylindrical flywheel at one or more predetermined speeds. A mechanism for moving the tire's rotating shaft brings the tire into contact with the outer or inner track of the cylindrical flywheel, according to a given force or displacement. This contact, through a driving effect, also rotates the tire.A sensor tracks and records the number of rotations the tire makes until the end of the test. In some cases, other sensors track and record parameters such as tire temperature, rolling resistance, or the pressure exerted by the tire on the flywheel. These machines have the drawback of not accurately representing real-world tire operating conditions, particularly due to the curvature of the cylindrical flywheel, which places greater stress on the tire and can lead to inaccurate readings of the tested parameters.

[0004] Other types of machines exist, such as those described in US patent application US4238954A, in which the cylindrical flywheel is replaced by a flexible belt moving along a predetermined closed circuit. Generally, the tire to be tested is brought into contact with the flexible belt in a flat section of the closed circuit. To control the contact forces exerted by the tire on the flexible belt and to limit the belt's deflection in this flat section, supports, such as friction plates or rotating supports, are placed beneath the flexible belt. As with flywheel testing machines, this type of machine is complex, often bulky, and requires significant space for installation.

[0005] Patent CN107121298B discloses an example of an endurance testing machine that does not rotate the tire under test. Such a machine performs only cyclic loading using a linear motion, pressing the tire against a plate at a predetermined frequency and with a predetermined loading force. Again, this type of testing method is not representative of real-world driving conditions and requires significant testing times to determine the final wear of the tire. Furthermore, as with the other types of testing machines mentioned previously, these linear-loading testing machines are bulky and difficult to transport.

[0006] Testing machines can also be used to test airless tires in cold environments where temperatures can drop well below 0°C. Airless tires are unique in that they carry the load using structural elements that form a casing, and their performance is comparable to that of a conventional tire subjected to the internal pressure of a gas, usually air. Airless tires can be used for specific applications, such as on vehicles that must withstand extreme cold, typically down to temperatures of 40 K. Such temperatures can be encountered by vehicles, such as lunar rovers, sent into outer space.

[0007] Thus, the need arose to monitor the performance of tires, particularly airless ones, subjected to mechanical stresses combined with very cold environments.

[0008] In order to reproduce the atmosphere of extreme cold and the conditions encountered in outer space it is possible to use a thermal vacuum chamber (in English Thermal Vacuum Chamber or TVAC), which allows control of the temperature, pressure and gas content of the interior space of said thermal vacuum chamber.

[0009] Such thermal vacuum chambers typically allow for achieving a vacuum and temperatures on the order of 40 K. It is known that increasing the size of thermal vacuum chambers leads, on the one hand, to increased costs, both in terms of purchase and operation, and, on the other hand, to increased technical difficulties in maintaining a cold environment and a vacuum within the interior. Furthermore, installing control equipment such as is commonly used—that is, bulky and difficult to transport—within a thermal vacuum chamber is industrially complex.

[0010] The object of the present invention is therefore to propose a pneumatic control machine, representative of real conditions of use, with a small footprint, easy to transport and to implement in a small thermal vacuum chamber.

[0011] The objects assigned to the invention are reached by means of a control machine, intended to simultaneously control a first and a second identical pneumatic, characterized in that it comprises: -a self-supporting chassis comprising an interface means for placing said self-supporting chassis on a flat surface, - a first rotation hub connected to the self-supporting chassis by a pivot joint with axis of rotation XX', said first rotation hub being intended to removably receive a first rim on which the first tire is mounted, said first rim being mounted concentrically at axis of rotation XX', - a second rotation hub connected to the self-supporting chassis by a pivot joint with axis of rotation YY' parallel to axis of rotation XX', said axis of rotation YY' being located at a distance E from axis of rotation XX', along a direction parallel to a segment ZZ' perpendicular to the respective axes of rotation XX', YY' and passing through said axes of respective rotations XX', YY', said second rotation hub being intended to receive, in a removable manner, a second rim on which a second tire is mounted, said second rim being mounted concentrically to the rotation axis YY', said second rotation hub being positioned so that an axially median plane to the first tire is coplanar with an axially median plane to the second tire, -at least one motor driving the rotation of the first or second rotation hub, -a system for adjusting the center distance E allowing the first tread of the first tire to be placed against a second tread of the second tire in order to obtain a flat contact surface between the first and second tires, -at least one force sensor to determine the pressure exerted by the first tire on the second tire, -at least one rotation sensor enabling the determination of the number of rotations performed by the first and second tires during the control of said first and second tires, -a rolling resistance sensor to determine the evolution of the rolling resistance of the first and second tires, -electrical connectors intended to transmit electrical energy to at least one motor, at least one force sensor, at least one rotation sensor and the rolling resistance sensor.

[0012] Essentially, the invention provides a simple, compact, lightweight testing machine that is easy to install in a thermal vacuum chamber. Specifically, the presence of at least one rotation sensor allows for monitoring the endurance of the first and second tires by recording the number of rotations completed before potential failure. Furthermore, the testing machine allows for the simultaneous testing of two tires, which is particularly advantageous when a large series of tires needs to be inspected.

[0013] The presence of a rolling resistance sensor associated with at least one force sensor and at least one rotation sensor makes it possible to obtain a versatile control machine capable of performing several kinds of controls simultaneously, in a simple and economical way.

[0014] In some embodiments, a projection system positions an interface body between the first tread and the second tread, allowing the wear of the first and second tires to accelerate during inspection.

[0015] The presence of the projection system of an interface body allows the control machine to simultaneously test the endurance and wear resistance of the first and second tires in a simple and economical way.

[0016] In a preferred embodiment, at least one force sensor is integrated into one of the first or second rotation hubs, thus maintaining compactness while providing a means of monitoring the evolution of the contact force exerted by the first tire on the second tire. Specifically, the at least one force sensor enables the end of the monitoring process when the contact force falls below a predetermined threshold.

[0017] In a preferred embodiment, the interface means includes a clamping system allowing the self-supporting chassis to be removably fixed to the flat surface.

[0018] The clamping system makes it possible to immobilize and prevent unwanted movements of the control machine during the inspection while allowing for quick and easy installation and removal of said control machine from the flat surface.

[0019] Preferably, the center distance adjustment system E is a manual linear motion system comprising a manual actuator for moving, along a displacement axis corresponding to segment ZZ', at least the first or second rotation hub. Using a manual center distance adjustment system E allows for a simple, lightweight, and quick-to-operate system that requires no additional energy.

[0020] Advantageously, the center distance adjustment system E is a removable system, thus allowing for an extremely compact control machine, said system of center distance adjustment E can be removed when center distance adjustment E is complete, thereby reducing the footprint of the endurance testing machine.

[0021] Preferably, the self-supporting chassis is a telescopic self-supporting chassis along at least two directions XI and Y1 perpendicular to each other and perpendicular to the respective axes of rotation XX', YY', the direction XI being a direction parallel to the segment ZZ'.

[0022] The use of a telescopic self-supporting chassis allows the dimensions of the self-supporting chassis to be adapted to the dimensions of the first and second tires which can be of variable diameter and width.

[0023] Advantageously, the first and second rotation hubs are positioned and oriented so as to obtain, in any plane parallel to a plane X1Z1 passing through the respective rotation axes XX', YY', a projection of the external dimensions of the first and second tires contained within the projection, in any plane X1Z1, of the external dimensions of the self-supporting chassis. Such positioning of the first and second hubs allows for a very small overall footprint for the testing machine, even when the first and second tires are mounted on the endurance testing machine.

[0024] Advantageously, at least one motor is integrated into one of the first or second rims, making it possible to avoid having at least one motor protruding from the first or second rims, thus ensuring better compactness of the endurance control machine.

[0025] The invention also relates to a control device for use in a cold and controlled environment, intended to simultaneously control first and second tires in a cold and controlled atmosphere environment, said control device for use in a cold and controlled environment comprising: -a thermal vacuum chamber comprising, on the one hand, a sealed enclosure including sealed panels, an access door and a flat surface, and, on the other hand, a control system allowing the temperature and atmosphere inside said sealed enclosure to be controlled, -the control machine for the different embodiments described above, intended to be placed, in a removable manner, on the flat surface of the sealed enclosure of the thermal vacuum chamber, -Additional electrical connectors designed to cooperate removably with the electrical connectors of the control machine, - a tracking and recording system cooperating with at least one rotation sensor, at least one force sensor and the rolling resistance sensor in order to track and record the number of rotations made by the first and second tires, the support force of the first tire on the second tire and the rolling resistance of said first and second tires.

[0026] Essentially, the controlled cold environment testing system allows the previously described testing machine to be implemented in a small thermal vacuum chamber, thus limiting the manufacturing and operating costs of said thermal vacuum chamber and, consequently, the costs of implementing the cold testing machine. Furthermore, the possibility of installing the testing machine in a removable manner within the thermal vacuum chamber facilitates the use of existing thermal vacuum chambers where the modifications required for installing the testing machine are minimal, thereby allowing the thermal vacuum chamber to be used for other applications.Furthermore, the additional electrical connectors designed to cooperate removably with the electrical connectors allow for quick and easy installation and removal of the control machine, while ensuring the power supply to the various electrical sensors and actuators.

[0027] Advantageously, a complementary clamping system cooperates with the clamping system to removably fix the control machine, thus preventing any untimely movement of said control machine during the performance of the endurance test, while ensuring quick and easy placement and removal of said control machine in the sealed enclosure of the thermal vacuum chamber.

[0028] The invention also relates to a method for testing the first and second tires in a cold and controlled environment, implementing the control device in a cold and controlled environment defined previously and comprising the following steps: - placement of the first and second tires to be tested on the testing machine, -use of the center distance adjustment system E in order to obtain a target center distance value El allowing the first tread of the first tire to rest on the second tread of the second tire so as to obtain a flat contact surface, the target center distance value El being less than the outside diameter of said first and second tires to be tested, -installation of the control machine within the sealed enclosure of the thermal vacuum chamber, -Electrical connection of the control machine by connecting the electrical connectors with the complementary electrical connectors, -activation of the control system to change the temperature and gas content of the atmosphere inside the sealed enclosure towards a predetermined temperature T and a predetermined gas content G respectively, -during the evolution of the temperature and gas content inside the sealed enclosure, activation of at least one motor to rotate the first and second pneumatics at a speed VI, -when the temperature and gas content inside the sealed enclosure have reached temperature T and gas content G respectively, activation of at least one motor to rotate the first and second pneumatics at a speed V2, -monitoring and recording, by the tracking and recording system, of the values ​​transmitted by the rolling resistance sensor, by at least one force sensor and when the measured force falls below a predetermined threshold S, recording of the number of rotations made by the first and second pneumatics and deactivation of at least one motor to stop the rotation of said first and second pneumatics, -electrical disconnection of the control machine by disconnecting the electrical connectors from the complementary electrical connectors, -removal of the control machine from the sealed enclosure of the thermal vacuum chamber.

[0029] Essentially, the method of the invention makes it possible to carry out control tests in a cold and controlled environment of the first and second tires in a simple and rapid manner, with a limited number of steps and without unnecessary loss of time.

[0030] Preferably, the temperature T is at least equal to 40 K and at most equal to 373 K, and even more preferably at most equal to 213 K, thus allowing control to be carried out at temperatures corresponding to the temperatures encountered in outer space.

[0031] Advantageously, the speed VI is at least equal to one revolution per minute and at most equal to five revolutions per minute. Rotating the first and second tires during the temperature and gas content evolution phase inside the sealed enclosure prevents seizing of moving parts such as bearings or bushings, such seizing being due to rapid and uneven contraction or expansion of the different materials constituting the various moving parts.

[0032] Preferably, the speed V2 is variable and is at least 6 revolutions per minute and at most 700 revolutions per minute, and, even more preferably, at least 100 revolutions per minute and at most 350 revolutions per minute. The variable speed V2 is preferably greater than the maximum rotational speed of the tires in use on a vehicle so as to reduce the time required for tire inspection.

[0033] Advantageously, the target center distance El corresponds to at least 60% and at most 98% of the outside diameter of the first and second tires, thus allowing the first and second treads of the first and second tires to be deformed until a flat contact surface is obtained that is representative of the use of the first and second tires mounted on a vehicle rolling on the ground.

[0034] Advantageously, the threshold S is at least equal to 70% and at most equal to 95% of the value of the support effort communicated by at least one force sensor when starting at least one motor at speed V2.

[0035] When the first or second tire reaches the end of its lifespan, degradation of the first and / or second tire is often observed, resulting in a rapid decrease in the contact area between the first and second tires. Therefore, using a threshold S below which cold weather testing is stopped allows the test to be linked to the deterioration of the first and / or second tire.

[0036] Preferably, the first and second tires tested are airless tires.

[0037] Other objects, features and advantages of the invention will become apparent in more detail from the following description, as well as from the accompanying drawings, which are provided for illustrative purposes only and are not intended to be limiting, including: -Figure 1: Perspective view of a control machine according to the invention placed on a flat surface with the first and second tires to be tested. -Figure 2: Side view of a control machine according to the invention placed on a flat surface without the first and second tires to be tested. -Figure 3: Perspective view and with a sealed panel removed from a control device in a cold and controlled environment according to the invention. -Figure 4: Perspective view of a particular embodiment of the control machine according to the invention. -Figure 5: Perspective view of an embodiment of the control machine according to the invention with the first and second hubs having horizontal axes of rotation XX' and YY'.

[0038] In what follows, for the sake of clarity, the horizontal and vertical directions correspond to the natural orientation of figures 1 to 9. Similarly, the terms "up", "down", "lower", "upper" and their variants should be understood with reference to the vertical direction of the figures.

[0039] As can be seen in Figure 1, the present invention relates to a control machine 100, intended to simultaneously control a first and second identical pneumatic 10, 11, characterized in that it comprises a self-supporting chassis 1 including an interface means 13 allowing said self-supporting chassis 1 to be placed on a flat surface 12.

[0040] By self-supporting chassis 1, we must understand a chassis sufficiently rigid to be able to be moved by conventional lifting means, such as forklift trucks or mobile workshop cranes, without risking harmful and irreversible deformations of said self-supporting chassis 1.

[0041] As an example, the self-supporting chassis 1 can be made from a welded, bolted, glued, or riveted tubular aluminum structure. Other types of aluminum structures, such as rigid, solid, or honeycomb panels, can also be used.

[0042] Preferably, the structural elements, such as tubes, panels or any other type of element, do not have a material thickness exceeding 20mm, in order to reduce the weight and thermal inertia of the self-supporting chassis 1. As an example, for tires with an outside diameter of 880mm, the weight of the control machine 100, made mainly of aluminum tubes, sheets and plates, does not exceed 400kg.

[0043] The interface means 13 may include, for example, at least three feet, adjustable or not, allowing the self-supporting chassis 1 to be placed stably on a flat surface 12, which may be the upper surface of a workshop floor or the upper surface of a floor of an enclosed space.

[0044] In a preferred embodiment, the interface means 13 includes a clamping system 25 for removably fixing the self-supporting chassis 1 to the flat surface 12.

[0045] As further illustrated in Figure 1, the control machine 100 also includes: - a first rotation hub 2 connected to the self-supporting chassis 1 by a pivot joint with axis of rotation XX', said first rotation hub 2 being intended to receive, in a removable manner, a first rim 14 on which the first tire 10 is mounted, said first rim 14 being mounted concentrically at axis of rotation XX', - a second rotation hub 3 connected to the self-supporting chassis 1 by a pivot joint with axis of rotation YY' parallel to axis of rotation XX', said axis of rotation YY' being located at a distance E from axis of rotation XX', along a direction parallel to a segment ZZ' perpendicular to the respective axes of rotation XX', YY' and passing through said respective axes of rotation XX', YY', said second rotation hub 3 being intended to receive, in a removable manner, a second rim 15 on which a second tire 11 is mounted, said second rim 15 being mounted concentrically at axis of rotation YY',said second rotation hub 3 being positioned so that one, axial plane median to the first tire 10 or coplanar with an axial plane median to the second tire 11.

[0046] Preferably, and as can be seen in Figure 1 and Figure 5, the rotation axes XX' and YY' are oriented horizontally or vertically in order to obtain a control machine 100 having a general parallelepiped shape that is easier to position in a workshop or enclosed space.

[0047] As is known, the pivot links, used to connect the first and second rotation hubs 2, 3 with the self-supporting chassis 1, are bearing housings, lubricated bearings or any other similar device.

[0048] The first and second rims 14, 15 can be positioned, in a removable manner, on the first and second rotation hubs 2, 3 respectively by bolting, or by electromagnetic locking systems, such as, for example, electromagnetic expanding mandrels.

[0049] By axially median plane to the first tire 10 or to the second tire 11, we must understand a plane perpendicular to the axis of rotation of the tire and passing through the axial middle of the tread of said tire.

[0050] As can be seen in Figure 1, the control machine 100 includes at least one motor 4 driving in rotation either the first rotation hub 2 or the second rotation hub 3.

[0051] In some unclaimed embodiments, the control machine 100 may include two motors, a first motor serving to drive the first rotation hub 2 and a second motor driving the second rotation hub 3. The use of two motors makes it possible to limit the size of each motor and therefore the overall size of the control machine 100.

[0052] Preferably, at least one motor 4 is an electric motor, which is not very sensitive to temperature changes.

[0053] As shown in Figure 1, the control machine 100 further includes a center distance adjustment system 5 allowing a first tread 16 of the first tire 10 to be supported on a second tread of bearing 17 of the second tire 11 so as to obtain a flat contact surface 18 between the first and second tires 10, 11.

[0054] The flatness of the contact surface 18 allows for a simple representation of the actual driving conditions of the first and second tires 10, 11 when used on moving vehicles. For example, the endurance limit check of the first and second tires 10, 11, performed by the testing machine 100, does not overestimate or underestimate the results of said endurance limit.

[0055] The center distance adjustment system 5 may include a device for viewing the center distance value E in a simple way using a pointed piece, connected to the first or second rotating hub 2, 3 movable, and sliding along a graduated ruler to indicate the center distance value E.

[0056] As can be seen in Figure 1 and Figure 2, the control machine 100 also includes: -at least one force sensor 9 allowing the determination of the support force of the first tire 10 on the second tire 11, -at least one rotation sensor 19 allowing the number of rotations performed by the first and second pneumatics 10, 11 to be determined during the control of said first and second pneumatics 10, 11, -a rolling resistance sensor 6 allowing the determination of the evolution of the rolling resistance of the first and second tires 10, 11, -electrical connectors 7 intended to transmit electrical energy to at least one motor 4, at least one force sensor 9, at least one rotation sensor 19 and the rolling resistance sensor 6.

[0057] At least one force sensor 9 can be, for example, a piezoelectric type sensor or a strain gauge sensor, which can be placed on the self-supporting chassis 1 or on the center distance adjustment system 5 E.

[0058] In a preferred embodiment, at least one force sensor 9 is integrated into one of the first or second rotation hubs 2, 3.

[0059] In some unclaimed embodiments, two force sensors 9 are used and can be integrated into the first rotation hub 2 and the second rotation hub 3.

[0060] The at least one rotation sensor 19 may be, for example, an incremental or absolute encoder, contactless or with contact, which may be placed on the first or second rotation hub 2, 3 or on the shaft of at least one motor 4.

[0061] In some unclaimed embodiments, each of the first and second rotation hubs 2, 3 is equipped with a rotation sensor 19, making it possible to know precisely the number of revolutions made by each of said first and second hubs 2, 3 even in case of slippage, at the level of the flat contact surface 18, of the first tread 16 relative to the second tread 17.

[0062] The rolling resistance sensor 6 can be, for example, a torque sensor mounted on the first or second rotating hub 2, 3, or a sensor measuring the electrical current consumption of at least one motor 4 during the control operation.

[0063] In some embodiments, and as illustrated in Figure 5, a projection system 27 positions an interface body between the first tread 16 and the second tread 17, allowing the wear of the first and second tires 10, 11 to be accelerated during the inspection.

[0064] The interface body, also called the "third body", can be, for example, regolith, silica, or any other abrasive material that can flow and accelerate the abrasion of the first and second treads 16, 17.

[0065] Preferably, and as shown in Figure 5, when the interface body is positioned between the first tread 16 and the second tread 17, the rotation axes XX' and YY' of the first and second rotation hubs 2, 3 respectively have a horizontal direction in order to allow the interface body to be held for a longer time between said first tread 16 and said second tread 17.

[0066] Preferably, and as shown in Figure 1, the center distance adjustment system 5 is a manual linear motion system comprising a manual actuator for moving, along a displacement axis corresponding to segment ZZ', at least the first or second rotation hub 2, 3. The manual actuator may comprise, in a known manner, a crank driving a screw / nut system or a crank driving a toothed wheel associated with a rack, the rotation of the crank allowing the movement of at least the first or second rotation hub 2, 3 until the center distance E corresponds to a predetermined center distance value E. Preferably, only the first rotation hub 2 is moved by actuation of the manual actuator.

[0067] In other unclaimed embodiments, the center distance adjustment system 5 E is a linear or eccentric displacement system, automated by means of an electric or electromagnetic actuator.

[0068] Advantageously, the center distance adjustment system 5 is a removable system that can be detached once the center distance E has been adjusted. The removal and installation of the removable center distance adjustment system 5 can be accomplished by snapping, clipping, or magnetically attaching said adjustment system 5 to the self-supporting chassis 1.

[0069] Preferably, the self-supporting chassis 1 is a self-supporting telescopic chassis along at least two directions XI and Y1 perpendicular to each other and perpendicular to the respective axes of rotation XX', YY', the direction XI being a direction parallel to the segment ZZ'.

[0070] As is known, the telescopic function of the self-supporting telescopic chassis 1 can be achieved by systems of electric jacks animating tubes that fit together and slide into each other.

[0071] Advantageously, and as can be seen in Figure 4, the first and second rotation hubs 2, 3 are positioned and oriented so as to obtain, in any plane parallel to a plane X1Z1 passing through the respective rotation axes XX', YY', a projection of the external dimensions of the first and second tires 10, 11 contained within the projection, in any plane X1Z1, of the external dimensions of the self-supporting chassis 1. In such an embodiment, as shown in Figure 4, The motor is preferably mounted with a right-angle gearbox so as to be positioned horizontally and thus obtain a particularly compact 100 control machine.

[0072] Advantageously, at least one 4-cylinder motor is integrated into one of the first or second rims 14, 15.

[0073] As can be seen in Figure 3, the invention also relates to a cold and controlled environment control device 200 intended to simultaneously control first and second tires 10, 11 in a cold environment and under a controlled atmosphere, said cold and controlled environment control device 200 comprising: -a thermal vacuum chamber 20 comprising, on the one hand, a sealed enclosure 21 comprising sealed panels 28, an access door 22 and a flat surface 12, and, on the other hand, a control system 23 allowing the temperature and atmosphere inside said sealed enclosure 21 to be controlled, -the control machine 100 of the different embodiments previously described, intended to be placed, in a removable manner, on the flat surface 12 of the sealed enclosure 21 of the thermal vacuum chamber 20, -additional electrical connectors 8 intended to cooperate removably with the electrical connectors 7 of the control machine 100, -a tracking and recording system 24 cooperating with at least one rotation sensor 19, at least one force sensor 9 and the rolling resistance sensor 6 in order to track and record the number of rotations made by the first and second tires 10, 11, the support force of the first tire 10 on the second tire 11 and the rolling resistance of said first and second tires 10, 11.

[0074] As is known, the airtight panels 28 are insulating panels connected together in a sealed manner to form a closed chamber, generally cubic or parallelepiped in shape. The access door 22 generally includes a seal and a locking system to maintain the airtightness of the airtight enclosure 21 when said access door 22 is closed. As is known to those skilled in the art, the thermal vacuum chamber 20 also includes at least one airtight bulkhead penetration allowing a conduit to communicate with the interior of the sealed enclosure 21, said conduit being connected to a device, such as a vacuum pump, for controlling the atmosphere inside said sealed enclosure 21. Cable glands are generally used to allow electrical cables to run from outside the sealed enclosure 21 to the complementary electrical connectors 8.

[0075] Advantageously, and as illustrated in Figure 3, a supplementary clamping system 26 cooperates with the clamping system 25 to removably fix the control machine 100, said supplementary clamping system 26 being able to be added in the thermal vacuum chamber 20 and being able to be a flange, a jack, a hook, an expanding mandrel or any other equivalent device.

[0076] The invention also relates to a method for checking the first and second tires 10, 11 in a cold and controlled environment, implementing the cold and controlled environment checking device 200 defined previously and comprising the following steps: -installation of the first and second pneumatics 10, 11 to be tested on the control machine 100, - Use of the center distance adjustment system 5 to obtain a target center distance value El allowing the first tread 16 of the first tire 10 to bear against the second tread 17 of the second tire 11 so as to obtain a flat contact surface 18, the target center distance value El being less than the outside diameter of said first and second tires 10, 11 to be tested, - Placement of the control machine 100 in the sealed enclosure 21 of the thermal vacuum chamber 20, - Electrical connection of the control machine 100 by connecting the electrical connectors 7 with the complementary electrical connectors 8, - Activation of the control system 23 to change the temperature and gas content of the atmosphere inside the sealed enclosure 21 towards respectively a predetermined temperature T and a predetermined gas content G,-during the evolution of the temperature and gas content inside the sealed enclosure 21, activation of at least one motor 4 to rotate the first and, second tires 10, 11 at a speed VI, -when the temperature and gas content inside the sealed enclosure 21 have reached temperature T and gas content G respectively, activation of at least one motor 4 to rotate the first and second pneumatics 10, 11 at a speed V2, -monitoring and recording, by the monitoring and recording system 24, of the values ​​transmitted by the rolling resistance sensor 6, by at least one force sensor 9 and when the measured force falls below a predetermined threshold S, recording of the number of rotations carried out by the first and second pneumatics 10, 11 and deactivation of at least one motor 4 to stop the rotation of said first and second pneumatics 10, 11, -electrical disconnection of the control machine 100 by disconnecting the electrical connectors 7 from the complementary electrical connectors 8, -removal of the control machine 100 from the sealed enclosure 21 of the thermal vacuum chamber 20.

[0077] Adjusting the center distance E, before the control machine 100 is placed in the sealed enclosure 21 of the thermal vacuum chamber 20, allows the first tread 16 to rest on the second tread 17, thus reducing the external dimensions of the first and second tires 10, 11. This reduction in dimensions therefore allows the use of a smaller thermal vacuum chamber 20.

[0078] When the first and second pneumatics 10, 11 are controlled under extra-atmospheric conditions, the predetermined temperature T will be 40 K and the predetermined gas content G will be close to a vacuum.

[0079] Preferably, the temperature T is at least equal to 40 K and at most equal to 373 K, and even more preferably at most equal to 213 K.

[0080] Advantageously, the speed V1 is at least equal to one revolution per minute and at most equal to five revolutions per minute.

[0081] Preferably, the speed V2 is variable and is at least equal to 6 revolutions per minute and at most equal to 700 revolutions per minute, and, even more preferably, at least equal to 100 revolutions per minute and at most equal to 350 revolutions per minute.

[0082] Advantageously, the target center distance El corresponds to at least 60% and at most 98% of the outside diameter of the first and second tires 10, 11.

[0083] Advantageously, the threshold S is at least equal to 70% and at most equal to 95% of the value of the support effort communicated by at least one force sensor 9 when starting at least one motor 4 at speed V2.

[0084] Preferably, the first and second tires 10, 11 tested are airless tires.

Claims

DEMANDS 1. Control machine (100), intended to simultaneously control a first and second identical tire (10, 11), characterized in that it comprises - a self-supporting frame (1) including an interface means (13) allowing said self-supporting frame (1) to be placed on a flat surface (12), - a first rotation hub (2) connected to the self-supporting frame (1) by a pivot joint with axis of rotation (XX'), said first rotation hub (2) being intended to receive, in a removable manner, a first rim (14) on which the first tire (10) is mounted, said first rim (14) being mounted concentrically to the axis of rotation (XX'), - a second rotation hub (3) connected to the self-supporting chassis (1) by a pivot joint with axis of rotation (YY') parallel to the axis of rotation (XX'), said axis of rotation (YY') being center-to-center distance E from the axis of rotation (XX'), along a direction parallel to a segment (ZZ') perpendicular to the respective axes of rotation (XX', YY') and passing through said respective axes of rotation (XX', YY'), said second rotation hub (3) being designed to removably receive a second rim (15) on which a second tire (11) is mounted, said second rim (15) being mounted concentrically to the axis of rotation (YY'), said second rotation hub (3) being positioned so that an axially median plane to the first tire (10) is coplanar with an axially median plane to the second tire (11), - at least one motor (4) driving the rotation of the first rotation hub (2) or the second rotation hub (3), - a system for adjusting the center distance E allowing a first tread (16) of the first tire (10) to be pressed against a second tread (17) of the second tire (11) so as to obtain a flat contact surface (18) between the first and second tires (10, 11), - at least one force sensor (9) allowing the force exerted by the first tire (10) on the second tire (11) to be determined, -at least one rotation sensor (19) enabling the determination of the number of rotations performed by the first and second pneumatics (10, 11) during the control of said first and second tires (10, 11), - a rolling resistance sensor (6) allowing the determination of the evolution of the rolling resistance of the first and second tires (10, 11), -electrical connectors (7) intended to transmit electrical energy to at least one motor (4), at least one force sensor (9), at least one rotation sensor (19) and the rolling resistance sensor (6).

2. Inspection machine (100) according to claim 1, in which a projection system (27) positions an interface body between the first tread (16) and the second tread (17) allowing to accelerate the wear of the first and second tires (10, 11) during the inspection.

3. Control machine (100) according to any one of claims 1 or 2, wherein at least one force sensor (9) is integrated into one of the first or second rotation hubs (2, 3).

4. Control machine (100) according to any one of claims 1 to 3, wherein the interface means (13) comprises a clamping system (25) allowing the self-supporting frame (1) to be removably fixed to the flat surface (12).

5. Control machine (100) according to any one of claims 1 to 4, wherein the center distance adjustment system (5) E is a manual linear displacement system comprising a manual actuator enabling displacement, along a displacement axis corresponding to the segment (ZZ'), of at least the first or second rotation hub (2, 3).

6. Control machine (100) according to claim 5, wherein the center distance adjustment system (5) E is a removable system.

7. Testing machine (100) according to any one of claims 1 to 6, wherein the self-supporting frame (1) is a telescopic self-supporting frame along at least two directions XI and Y1 perpendicular to each other and perpendicular to the respective axes of rotation (XX', YY'), direction XI being a direction parallel to segment (ZZ').

8. Control machine (100) according to claim 7, in which the first and second rotation hubs (2, 3) are positioned and oriented so as to obtain, in any plane parallel to a plane (X1Z1) passing through the respective rotation axes (XX', YY'), a projection of the external dimensions of the first and second tires (10, 11) contained in the projection, in any plane (X1Z1), of the external dimensions of the self-supporting chassis (1).

9. Control machine (100) according to any one of claims 1 to 8, in which at least one motor (4) is integrated into one of the first or second rim (14, 15).

10. Control device for cold and controlled environments (200) intended to simultaneously control first and second tires (10, 11) in a cold environment and under a controlled atmosphere, said control device for cold and controlled environments (200) comprising: -a thermal vacuum chamber (20) comprising, on the one hand, a sealed enclosure (21) comprising sealed panels 28, an access door (22) and a flat surface (12), and, on the other hand, a control system (23) allowing control of the temperature and atmosphere inside said sealed enclosure (21), -the control machine (100) according to claims 1 to 9, intended to be placed, in a removable manner, on the flat surface (12) of the sealed enclosure (21) of the thermal vacuum chamber (20), -additional electrical connectors (8) intended to cooperate removably with the electrical connectors (7) of the control machine (100), -a tracking and recording system (24) cooperating with at least one rotation sensor (19), at least one force sensor (9) and the rolling resistance sensor (6) in order to track and record the number of rotations performed by the first and second tires (10, 11), the support force of the first tire (10) on the second tire (11) and the rolling resistance of said first and second tires (10, 11).

11. Control device in a cold and controlled environment (200) according to claim 10, in which a complementary clamping system (26) cooperates with the clamping system (25) to removably fix the control machine (100).

12. Method for testing the first and second tires (10, 11) in a cold and controlled environment, implementing the testing device in a cold and controlled environment (200) defined according to claims 10 or 11, comprising the following steps: - placement of the first and second tires (10, 11) to be tested on the testing machine (100), -use of the adjustment system (5) of the center distance E in order to obtain a target center distance value El allowing the first tread (16) of the first tire (10) to bear against the second tread (17) of the second tire (11) so as to obtain a flat contact surface (18), the target center distance value El being less than the outside diameter of said first and second tires (10, 11) to be tested, -installation of the control machine (100) in the sealed enclosure (21) of the thermal vacuum chamber (20), -electrical connection of the control machine (100) by connecting the electrical connectors (7) with the complementary electrical connectors (8), -activation of the control system (23) to change the temperature and gas content of the atmosphere inside the sealed enclosure (21) towards respectively a predetermined temperature T and a predetermined gas content G, -during the evolution of the temperature and gas content inside the sealed enclosure (21), activation of at least one motor (4) to rotate the first and second pneumatics (10, 11) at a speed VI, -when the temperature and gas concentration inside the sealed enclosure (21) have reached temperature T and gas concentration G respectively, activation of at least one motor (4) to rotate the first and second pneumatics (10, 11) at a speed V2 - monitoring and recording, by the monitoring and recording system (24), of the values ​​transmitted by the rolling resistance sensor (6), by at least one force sensor (9) and when the measured force falls below a predetermined threshold S, recording of the number of rotations carried out by the first and second pneumatics (10, 11) and deactivation of at least one motor (4) to stop the rotation of said first and second pneumatics (10, 11), - electrical disconnection of the control machine (100) by disconnecting the electrical connectors (7) from the complementary electrical connectors (8), - removal of the control machine (100) from the sealed enclosure (21) of the thermal vacuum chamber (20).

13. Method for testing the first and second tires (10, 11) in a cold and controlled environment according to claim 12, wherein the temperature T is preferably at least equal to 40 K and at most equal to 373 K, and even more preferably at most equal to 213 K.

14. Method for testing in a cold and controlled environment the first and second tires (10, 11) according to one of claims 12 or 13, wherein the speed VI is at least equal to one revolution per minute and at most equal to five revolutions per minute.

15. Method for testing in a cold and controlled environment the first and second tires (10, 11) according to any one of claims 12 to 14, wherein the speed V2 is preferably variable and is at least equal to 6 revolutions per minute and at most equal to 700 revolutions per minute, and, even more preferably, at least equal to 100 revolutions per minute and at most equal to 350 revolutions per minute.

16. Method for testing in a cold and controlled environment the first and second tires (10, 11) according to any one of claims 12 to 15, wherein the target center distance El corresponds to at least 60% and at most 98% of the outside diameter of the first and second tires (10, 11).

17. Method for checking in a cold and controlled environment the first and second tires (10, 11) according to any one of claims 12 to 16, wherein the threshold S is at least equal to 70% and at most equal to 95% of the value of the support force communicated by at least one force sensor (9) when starting at least one motor (4) at speed V2.

18. Method for testing in a cold and controlled environment the first and second tires (10, 11) according to any one of claims 12 to 17, wherein said first and second tires (10, 11) tested are airless tires.

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