RU2540219C2 - Vehicle antiskid wheel - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: wheel consists of elements embedded therein and including the material with magnetocaloric effect that can be cooled by ambient air or solids of revolution. Vehicle body incorporates permanent magnets to be extended towards the wheel and solids of revolution, said permanent magnets being fitted inside said solids of revolution. At braking on icy road, solids of revolution with permanent magnets extend toward the wheel while elements of magnetocaloric material are heated to transfer heat to solids of revolution or to permanent magnets depending on what element not-heat-insulated contacts with the wheel.

EFFECT: higher wheel friction on ice-covered ground.

4 cl, 16 dwg

Description

The invention mainly relates to devices that prevent wheel slippage, as well as to refrigeration for refrigerators operating on the basis of the magnetocaloric effect.

A car tire [1], an anti-skid element used for a car tire, and a method for preventing tire slipping are known.

Prevention of slipping of a car tire is achieved by creating negative pressure in the inner space of the water-absorbing recess while expanding and changing the shape of this recess formed in the tire tread, when it comes into contact with the road, and water is sucked between the tread surface and the road surface under the influence of negative pressure, simultaneously holding the sucked water between the many hairs located in the water-suction recess, so as to create a traction force of the tire with the surface of the road by the formation of a suction-adhesion force and freezing force between the tread surface and the road surface, and the outflow of water held between the hairs, at the moment when the water-suction recess comes out of contact with the road, under the action of a force restoring the shape of the water-suction recess, and centrifugal force created by the rotation of the tire.

The device implemented by this method does not provide for forced cooling of the tire surface, which heats up when driving and, especially, when braking. As a result, when braking under icy conditions, the surface layer of ice under the tire melts, significantly reducing the friction coefficient, especially at an ambient temperature close to the temperature of ice melting.

Known magnetic refrigerator [2], comprising a housing with a rotating wheel, which is rigidly mounted on the shaft and made of a working substance with a magnetocaloric effect (FEM), in the form of coaxial rings mounted on each other with radial channels for the passage of warm and cold coolant flows and divided into segments by impermeable heat-insulating partitions, a magnet covering the part of the wheel in the axial direction, a gas distribution device for supplying and removing heat carrier, located in the center noy body portion, and a load heat exchanger is configured as a housing of the refrigerator, is rigidly associated with the wheel arranged therein rotatably together with the latter, wherein between the housing and the outer surface of the wheel is formed a gap for the passage of the cold coolant flow.

This design does not allow, without a significant refinement of the design of the refrigerator, to use this device for cooling the surface of a vehicle tire.

A device is known [3], where, as described in a magnetic refrigerator, a rotating structure is used. It consists of a wheel containing segments with gadolinium powder, as well as a powerful permanent magnet.

The design is made in such a way that the wheel scrolls through the working gap of the magnet, in which the magnetic field is concentrated. When a segment with gadolinium enters a magnetic field in the gadolinium, a magnetocaloric effect occurs - it heats up. This heat is removed by a water-cooled heat exchanger. When gadolinium leaves the zone of the magnetic field, a magnetocaloric effect of the opposite sign occurs and the material is additionally cooled, cooling the heat exchanger with a second stream of water circulating in it. This stream is used to cool the cooling chamber of a magnetic refrigerator.

The disadvantage of this design is that in it to circulate the heat of the magnetocaloric refrigeration cycle, the circulating water is a heat carrier, which is not acceptable for the vehicle wheel.

A known tire design [4], preventing slipping on ice. According to the description, the sliding body in the form of a tire contains metal heating elements embedded in the tire. Power is supplied to the heating elements, as a result of which the heating elements melt the boundary layer of ice or snow. After melting the boundary layer of ice, it is repeatedly frozen under the influence of external temperature and provides a connection between ice / snow and the tire. Power is supplied to the heating elements in several ways. A sliding body uses, for example, a car battery as a power source.

In another example of a tire, heating elements include thin metal wires capable of receiving power and converting this power into heat energy to melt the boundary layer of ice / snow in contact with the tire. According to an embodiment, the user activates a switch, which allows power to be supplied to the heating elements when necessary to provide additional traction of the tire to the road surface covered with ice and snow. When the user switches the switch by pressing a special button on the vehicle’s control panel, the switch transfers power from the power source to the heating elements to melt the boundary layer of ice and snow and, thus, to change the coefficient of friction between the tire and ice and snow covering the road surface when the boundary layer re-freezes and improves tire grip on snow / ice.

The design drawback is that at an air temperature of about zero degrees Celsius, previous heating does not allow freezing the boundary layer of ice, because cold air will not be enough.

The heating elements act as “impulse brakes”, giving a heating pulse to the interface between the tire and the snow / ice. For example, when braking is needed, the boundary layer of ice melts. When the pulse stops, the melted spots on the tire are usually re-frozen in a few milliseconds under the influence of external temperature, providing strong connections between the tire and ice / snow. These connections contribute to the inhibition of tire movement relative to ice / snow. For faster cooling of the melted boundary layer of ice, the Peltier element is used.

Peltier element when applying current requires heat removal from the side opposite to the cooling side. If the cooling side is on the surface of the wheel, the heating side of the Peltier element will transfer heat to the inside of the wheel, so a heat removal system from the inside of the wheel will be required. In addition, the disadvantage of the Peltier element in this case is the need to supply electricity to the moving wheel, which reduces the reliability of the system.

In one embodiment of the tire, an automobile air conditioner is used in the re-freeze phase.

However, automobile air conditioning is usually not designed for the level of negative temperatures, as in this case, its thermal efficiency will be lower than with normal performance, in addition, its power should be quite large.

The closest analogue of the claimed invention adopted as a prototype is a vehicle wheel with a slippage prevention device according to the RF patent for utility model No. 127340 [5].

In the prototype, the vehicle’s wheel contains elements embedded in the wheel cooled by ambient air or rolling elements, the embedded elements containing magnetocaloric effect material, and permanent magnets equipped with rolling elements on the wheel side are placed in the vehicle’s body with the possibility of extension to the side of the wheel.

According to the utility model formula, description and illustrations to the patent, permanent magnets and rolling elements are separate elements spaced in space. Moreover, the permanent magnets are separated from the wheel with the formation of a gap by the rolling elements, which abut against the wheel when extending and thereby provide a minimum clearance between the wheel and the magnets.

This design provides that only part of the surface of the wheel is in contact with the rolling elements, most effectively cooling the embedded elements of magnetocaloric material. The other part of the surface of the wheel, located under the permanent magnets at a distance of the gap, is cooled only by outside air. Due to the fact that the magnetic induction decreases rapidly with distance from the magnet, it is necessary to ensure a minimum clearance between the magnet and the wheel. In such a gap, it is impossible to organize effective air cooling without additional means, therefore, in the claimed utility model, the cooling is actually mainly carried out due to the thermal conductivity to the rolling elements. The part of the wheel surface in contact with the rolling elements is cooled more strongly, because heat transfer under these conditions is much higher than heat transfer due to heat transfer to air.

Thus, in the prototype, only part of the surface of the wheel occupied by permanent magnets is cooled quite efficiently: quickly and with a high amount of heat transferred. The higher the efficiency of such cooling, the higher the efficiency of subsequent adiabatic cooling outside the action of a magnetic field, the lower the temperature of magnetic cooling.

The objective of the claimed invention is to increase the efficiency of magnetocaloric cooling.

The technical result is achieved in that the vehicle wheel with the slip prevention device contains elements embedded in the wheel including material with a magnetocaloric effect, which can be cooled by ambient air or rotation bodies, permanent magnets and rotation bodies are placed in the vehicle body with the possibility of extension to the side of the wheel , and permanent magnets are placed inside the bodies of revolution.

Due to the fact that the permanent magnets are placed inside the bodies of revolution, the area of effective cooling of elements made of magnetocaloric material that is heated by the action of a magnetic field increases.

In the first embodiment, the permanent magnets are placed inside the bodies of revolution motionless relative to the geometric axes of the bodies of revolution (i.e., the magnets do not rotate relative to the wheel), and the surfaces of the bodies of revolution in contact with the wheel are movable relative to the permanent magnets (i.e., rotate around the magnets behind due to friction on the wheel).

In another embodiment, the permanent magnets are fixed motionless relative to the bodies of revolution (i.e., rotate with them). The simplest embodiment of this embodiment is the introduction of magnets into bodies of revolution (or the manufacture of a body of revolution in the form of a monolithic magnet).

In the case of using several magnets, they are fixed inside the body of revolution, and in places of a minimum of magnetic flux from permanent magnets, the surfaces of the bodies of revolution are insulated. In this case, the magnetocaloric material, adiabatically cooling after leaving the magnetic field maximum, does not transfer useful cold to the body of revolution. Most simply, this option is implemented by fixing metal magnets in a plastic roller with low thermal conductivity.

A new set of essential features, namely the placement of permanent magnets inside the bodies of revolution, can significantly increase the area and cooling efficiency compared to the prototype.

The very options for placing permanent magnets inside the bodies of revolution: motionless relative to the geometrical axes of the bodies of revolution, with the possibility of rotating around the magnets only to the surfaces of the bodies of revolution in contact with the wheel; motionless relative to bodies of revolution, i.e. rotating with them, moreover, in one of the sub-variants of such a design, in places of a minimum of magnetic flux from permanent magnets, the surfaces of the bodies of revolution are insulated, are also new.

The option of placing permanent magnets inside the bodies of revolution motionless relative to the geometric axes of the bodies of revolution also suggests the possibility of using the magnets themselves as the physical axes of the bodies of revolution.

Since the new set of essential features of the proposed device is not known and does not follow explicitly from the prior art established by the patent and scientific literature, we can talk about its compliance with the criteria of "novelty" and "inventive step".

The invention is illustrated by drawings:

figure 1 shows a General view of the device in an inactive state, when the permanent magnets, relative to which the surfaces of the bodies of revolution are movable, are removed from the wheel;

figure 2 shows a General view of the device in the active state, when the permanent magnets interact with the embedded elements through contacting the wheel surface of the bodies of revolution;

figure 3 shows a section aa of the wheel (tire) of figure 2, the wheel contains embedded elements in the form of granules from a material with a magnetocaloric effect;

figure 4 shows a section aa of the wheel (tire) of figure 2, the wheel contains embedded elements of another known embodiment, consisting of a material with magnetocaloric effect, which are in contact with metal materials with high thermal conductivity;

figure 5 shows a section aa of the wheel (tire) of figure 2, which implements a well-known embodiment of embedded elements consisting of alternating layers of materials: with magnetocaloric effect, with high thermal conductivity and ferromagnetic materials (ferromagnetic steel);

figure 6 shows a view B of the body of revolution with a permanent magnet around which the surface of the body of revolution rotates;

Fig.7 shows a section bb embedded element of Fig.5 and Fig.12.

on Fig shows a General view of the device in an inactive state, when the permanent magnets mounted in the bodies of revolution, are removed from the wheel;

figure 9 shows a General view of the device in the active state, when the permanent magnets fixed in the bodies of revolution, are in contact with the wheel;

figure 10 shows a section of the GG wheel (tire) of Figure 9, the wheel contains embedded elements from granules of material with a magnetocaloric effect;

figure 11 shows a section of the GG wheel (tire) of figure 9, the wheel contains embedded elements of another embodiment, consisting of a material with magnetocaloric effect, which are in contact with a metal material with high thermal conductivity;

in Fig.12 shows a section of the GG wheel (tire) of Fig.9, which implements an embodiment of embedded elements consisting of alternating layers of materials: with a magnetocaloric effect, with high thermal conductivity and ferromagnetic materials (ferromagnetic steel);

on Fig shows a view D of the body of revolution with permanent magnets fixed inside and rotating together with the body of rotation;

on Fig shows a section of a body of revolution in a variant of its execution of a non-magnetic metal material;

on Fig shows a body of revolution, the outer surface of which is completely formed by magnets;

in Fig.16 shows a detailed section EE of the surface of the wheel (tire) of Fig.3 and a graph of the temperature of the granules of a material with magnetocaloric effect.

A vehicle wheel with a slippage prevention device (FIG. 1) consists of permanent magnets 1 located inside the vehicle body, located inside the bodies of revolution 2, the permanent magnets 1 being able to extend towards the wheel 3 (FIG. 2), and embedded in the wheel 3 elements 4 (Figure 3) made of granules of material with a magnetocaloric effect.

In the embodiment shown in Fig.1-7, the permanent magnets are placed inside the bodies of revolution motionless relative to the geometric axes of the bodies of revolution, and the surfaces of the bodies of revolution in contact with the wheel are movable relative to the permanent magnets. Figure 6 shows a design in which the permanent magnets are not only stationary relative to the geometric axes of the bodies of revolution, but are structurally themselves the physical axes of the bodies of revolution 2. In the simplest embodiment, the embedded elements are made in the form of granules 4 embedded in the manufacture of the protector protrusion 5 wheels (tires). If it is necessary to prevent slippage, the permanent magnets are advanced towards the wheel (Figure 2) and abut against it by the surface of the rotation elements 2.

In order to ensure sufficiently fast transfer of heat (cold) to the surface of the wheel, the granules of the material 4 with magnetocaloric effect are in contact with the embedded elements 6 (Figure 4) of a metal material with high thermal conductivity (for example, with copper or steel).

To increase magnetic induction at the location of the magnetocaloric material, in one of the options in the design of the embedded elements, an insert 7 (Fig. 5) of ferromagnetic material (ferromagnetic hardened steel) is used, and the magnetocaloric material 4 in layers (Fig. 7) is alternated with a metal material with high thermal conductivity 6 (for example, with copper). The steel insert 7 forms the core of the anti-skid stud. In this embodiment, the magnetocaloric material can be used in the form of a powder pressed between layers of metal (copper).

To reduce friction during rotation of the surface of the body of revolution 2 around the magnet 1, their design is made in the form of a ball bearing with balls 8 (Fig.6).

The wheel of the vehicle with the device to prevent slippage works as follows: if there is no need to prevent slippage, the permanent magnets 1 located on the vehicle body (Fig. 1) are retracted from the wheel 3 by a distance at which the magnetic induction in the body of the wheel 3 is minimal.

If it is necessary to prevent slippage, for example when braking under icy conditions, the permanent magnets 1 extend towards the wheel (Figure 2) and abut against it with the surfaces of the bodies of revolution 2 with minimal friction losses. In this case, the introduced elements 4 of the magnetocaloric substance are heated due to the action of a magnetic field, the heat of this heating is transferred to the surrounding air and bodies of revolution. The heat flux at the point of contact of the bodies of revolution due to thermal conductivity is significantly higher than the heat flux due to cooling by air, therefore, cooling is carried out mainly by bodies of revolution.

Heat is transferred to the surface of the body of revolution either through the material of the protrusion 5 of the tread, or through elements 6 of highly heat-conducting metal (copper or steel) that are in contact with the elements 4. In one of the known embodiments of the embedded elements, the magnetic flux through the embedded elements is enhanced by a ferromagnetic insert of steel 7, which plays the role of an anti-skid stud. The surfaces of the bodies of revolution 2 can be made, for example, in the form of surfaces of bearings with curly cuts (see Figure 5) to improve contact with wheel elements or anti-skid spikes. Cooling occurs due to the fact that the parts before contact with the wheel have a supply of cold, spent on cooling the embedded elements 2.

Despite the fact that the surface of the wheel is in contact with the rolling bodies 2 and interacts with the magnets 1 in turn, while the embedded elements 4 are also heated and cooled in turn, the resulting temperature after the wheel leaves the last magnet will be lower than after the first. This is due to the fact that between interactions with magnets 1, the embedded elements 2 are cooled almost adiabatically, because the transfer of cold from them to the surrounding air is minimal in comparison with the transfer of heat by thermal conductivity in contact with bodies of revolution. The result is a periodic cooling process with alternating heating and cooling, in which as the wheel passes under the magnets, both the temperature of the subsequent heating (under the influence of a magnetic field) and the subsequent cooling (in the absence of a magnetic field) decrease. Excessive heat of the magnetcaloric refrigeration cycle is removed due to heat conduction to the bodies of revolution (and to the magnets 1 through balls 8). The embedded elements 2 are heated only when the magnet 1 is above them, and at the same time they are able to remove the excess heat of the refrigeration cycle through the surface of the bodies of revolution. The temperature change of granules of a material with a magnetocaloric effect along the surface of the wheel (tire) is shown in Fig. 16. At the moment the tire touches the ice, it has a supply of cold, which is spent on cooling the surface of the tire and ice and freezing the surface of the tire. If the tire had not been pre-cooled, then during braking, due to friction, its temperature and the temperature of the ice surface would rise to the temperature of ice melting, a thin film of water would form between the tire and ice, significantly reducing the coefficient of friction of the tire against ice.

After the introduced elements of magnetocaloric material 4, due to the rotation of the wheel, leave the magnetic field of the permanent magnets, they are cooled, and then, having entered into thermal interaction with the ice surface on which the wheel rolls, through the surface of the wheel material (Figure 3 ) either through inserts 6 of highly heat-conducting material (Figure 4), or through ferromagnetic insert 7 (Figure 5) provide partial freezing of the wheel, increasing the friction coefficient and preventing slipping.

In another embodiment (Figs. 8-14), permanent magnets 10 are mounted in the bodies of revolution 9. The bodies of revolution 9 are, for example, rollers of a given shape made of plastic with low thermal conductivity. As a special case of execution, a monolithic permanent magnet can be a body of revolution (not shown in the drawings and, due to ease of operation, is not considered in the description), in this case the surface of the body of revolution is not thermally insulated. In addition, the magnets 10 can be mounted circumferentially close to each other, and their outer surface can be limited by the body of revolution 9 (Fig. 15), in which case the body of revolution is formed by several magnets.

If it is necessary to prevent slippage, for example, when braking under icy conditions, the rotation bodies 9 with permanent magnets 10 are pulled out towards the wheel (Fig. 9) and abut against it by the surfaces of the rotation bodies 2 or magnets 10. The embedded elements 4 of the magnetocaloric substance are heated due to the action of the magnetic field, the heat of this heating is transferred to the surrounding air, bodies of revolution 9 and magnets 10. The heat flux at the point of contact with the magnets 10 due to thermal conductivity is significantly higher than the heat flux due to hlazhdeniya air or by contact with the rotating bodies 9, so cooling is mainly due to the heat capacity of the permanent magnets 10.

In a simplified design, the wheel is in direct contact with the permanent magnets 10 and the heat of the magnetocaloric refrigeration cycle can be removed due to thermal conductivity directly to the permanent magnets 10, which increases the beneficial effect of using the mass of the structure.

Despite the fact that the surface of the wheel is in contact with the magnets 10 in turn, while the embedded elements 4 are also heated and cooled in turn, the resulting temperature after the wheel leaves the next magnet will be lower than after the previous one. This is due to the fact that between interactions with magnets 10, in places of minimum magnetic flux, the embedded elements 2 are cooled almost adiabatically, because the transfer of cold from them to the bodies of revolution is minimal due to the low thermal conductivity of the body of revolution in this zone. The result is a periodic cooling process with alternating heating and cooling, in which, as the wheel passes under the magnets 10, both the temperature of the subsequent heating and cooling decreases. The excess heat of the magnetocaloric refrigeration cycle is removed by heat conduction to the magnets 10. The embedded elements 2 are heated only when the magnet 10 is above them, and at the same time they are able to remove the excess heat of the refrigeration cycle inside the magnets 10 through their surface.

Figure 10 shows the contact of a roller of thermally insulated material with a wheel in which the embedded elements are dispersed magnetocaloric material in the form of granules.

11 shows the contact of a roller of thermally insulated material with a wheel, in which the embedded elements are magnetocaloric material in contact with a metal material in high thermal conductivity.

Figure 12 shows the contact of a roller of thermally insulated material with a wheel, in which a known embodiment of embedded elements consisting of alternating layers of materials is realized: with a magnetocaloric effect, with high thermal conductivity and ferromagnetic materials (ferromagnetic steel).

A construction is also possible (Fig. 14), in which the rotation body is a massive metal roller made of non-magnetic material with high thermal conductivity (for example, aluminum), in which permanent magnets 10 are embedded, and between the magnets the surface of such a roller is insulated with plastic inserts 12. In this design, the heat flux is diverted to a more massive body and at a higher speed, which increases the efficiency of the cooling cycle.

The range of the magnetic field in the manufacture of the device can be increased by increasing the length of the covering wheel of the arc of the permanent magnets 1 (Figure 2). In the extreme case, such an arc can occupy a significant part of the wheel circumference that is not in contact with the surface.

The proposed technical solution allows for freezing of the wheel even at zero and small positive ambient temperatures.

Information sources

1. Application for invention 95106677/11, 04/25/1995, cl. B60C 11/16. A car tire, an anti-skid member used for a car tire, and a method for preventing tire slipping.

2. A.S. 1668829, class F25B 21/00. Rotary magnetic refrigerator.

3. Magnetocaloric effect (Ames Laboratory press release. Ames Laboratory). AMT & S. Group of Companies (AMT & S Group Ltd.) http://www.amtc.ru/publications/articles/2025/.

4. RF patent RU 2289892, cl. H05B 3/84. Systems and methods for changing the interface between ice and an object.

5. RF patent for utility model RU 127340, cl. B60C 11/16. Vehicle wheel with slippage prevention device.

Claims (4)

1. Wheel of a vehicle with a slip prevention device, comprising elements embedded in the wheel, including material with a magnetocaloric effect, capable of being cooled by ambient air or bodies of revolution, permanent magnets and bodies of revolution are arranged to extend towards the wheel side of the vehicle, characterized in that permanent magnets are placed inside bodies of revolution. 2. The wheel with the device according to claim 1, characterized in that the permanent magnets are placed inside the bodies of revolution motionless relative to the geometric axes of the bodies of revolution, and the surfaces of the bodies of revolution in contact with the wheel are movable relative to the permanent magnets. 3. The wheel with the device according to claim 1, characterized in that the permanent magnets are fixed motionless relative to the bodies of revolution. 4. A wheel with a device according to claim 3, characterized in that in places of a minimum magnetic flux from permanent magnets, the surfaces of the bodies of revolution are insulated.

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