KR20080108095A - Braking systems with cooling - Google Patents

Abstract

A braking system comprises an axle (23), a support element (22) mounted on the axle, a brake ring (3) connected to the periphery of the support element (22) and a brake calliper (21) for applying a braking force to the brake ring (3). The brake ring (3) is connected to the support element (22) in such a manner that a conductive heat flow path is provided for conducting heat from the brake ring (3) into the support element (22). There is also an airflow path passing through the support element (22) and through the region in which the brake calliper (21) is situated for transferring heat by convection from the brake ring (3) and the brake calliper (21). ® KIPO & WIPO 2009

Description

Breaking System with Cooling System {BRAKING SYSTEMS WITH COOLING}

The present invention relates to a braking system, in particular but not limited to a braking system for a vehicle wheel.

In general, a braking system for a vehicle wheel functions by converting kinetic energy into thermal energy using a braking system that includes a surface with a high coefficient of friction to slow down the wheel. do. If the generated heat is not dissipated, the braking efficiency of the system becomes less and less, and eventually there is a problem that the brake does not work through a so-called brake fade phenomenon.

Drum brakes are particularly vulnerable to brake pads because the drums are heated by friction generating shoes rather than being used to dissipate heat by convection to the surrounding air.

In general, a disc brake is more effective than a drum brake, which is a brake pad attached to a brake disc attached to an associated wheel hub rather than being applied to the drum inner surface of the drum brake. This is because a greater pressure can be exerted by a caliper that compresses). Thus, the heating contact area between the friction pad of the disc brake and its associated disk can be significantly reduced compared to the heating contact area of the brake shoe with its associated drum for the same braking action. In general, 20% of the disc surface of the disc brake is severely heated by the disc pad and the remaining 80% can dissipate heat by convection to ambient air inside the associated wheel.

To improve the vehicle's braking system, manufacturers have increased the internal diameter of the vehicle wheels so that large diameter discs and large brake calipers can be mounted. With this, the braking leverage of the braking system can be increased as a result of the increased disk radius. However, the large radius of such a large disk means that the associated caliper must be considerably longer than that of conventional small disks to cover the depth of the disk.

In general, long, so-called "beam" calipers used with such large disks are four or six port constructions, which significantly increases the complexity and production cost of the caliper. In addition, the caliper significantly reduces the area of the exposed brake disc for cooling by convection to the air inside the wheel, and also reduces the air space available for cooling the disc by convection of the air inside the wheel concerned. It may worsen the "plug" effect.

Thus, a major inherent problem with both the drum and disc braking systems is that convection through air alone is generally insufficient to prevent brake fading from heat dissipation from the system. In addition, the design of the braking system itself tends to impede the flow of air over the surface, which must serve to cool the surface, thereby reducing its efficiency.

It is an object of the present invention to provide a braking system which can be particularly well cooled and which can consistently show high performance.

According to the invention, an axle, a support element mounted to the axle, a brake ring connected to the support member periphery and a braking force for applying the braking force to the brake ring A braking system is provided that includes a brake calliper, wherein the brake ring is coupled to the support member such that a conductive heat flow path conducts heat from the brake ring to the support member. And an air flow passage through the area where the brake caliper is installed and the support member for heat transfer by convection from the brake ring and the brake caliper.

Cooling the braking device by both heat conduction from the ring to the support member and convection cooling of the support member, the ring and brake calipers, providing excellent cooling and high performance, even continuous braking capability. It becomes possible to provide a braking system.

The braking system can be applied to a wheel of a vehicle, for example a motor vehicle. The wheel may comprise a hub and a support member. The support member may extend from the hub to the brake ring. The brake ring may be connected to or form part of a rim of the wheel.

While it is within the scope of the present invention to cool the air current generated by convection or other factors, the braking system preferably includes airflow generating means for creating a flow of air along the airflow passage. Do. For example, vanes may be installed to create a flow of air along the air flow passage. The vane may form part of the support member. In one embodiment of the invention, the vanes may be installed in the hub of the wheel. In another embodiment of the present invention, the vane may be installed on any one member, and the member may be the support member extending outwardly from the axle.

In order to install an effective air flow passage through the support member, the support member preferably has an opening that occupies most of its cross-sectional area. Preferably at least 20%, more preferably at least 40% of the cross section of the support member comprises at least one opening to allow air flow through the support member.

The brake ring may be detachably connected to the support member, or may be integrally formed with the support member. In both cases there must be a good conductive passageway for conducting heat from the brake ring to the support member. Accordingly, it is preferable that the interface of the brake ring and the support member comprise a continuous annular interface. The interface preferably has a cross-sectional area of at least 20%, preferably 50% or more of the brake ring cross-sectional area, immediately upstream of the interface. Thus, the heat flowing from the brake ring to the interface reduces to less than 50% of the cross sectional area available for heat conduction.

Preferably, the brake ring projects radially inward from the outside of the support member. In this case, when the brake caliper is positioned inside the brake ring, the brake ring may have a large diameter. The brake ring is planar, preferably in a plane perpendicular to the axis of rotation.

In addition to cooling by general air convection, providing an enclosed region around some of the brake rings and / or brake calipers, supplying fluid to and removing fluid from the region is also within the scope of the present invention. Is in. Such a device allows for more efficient heat exchange into the fluid, where the fluid can be a refrigerant and can be recycled.

In one aspect of the invention as defined above, a preferred type of braking system is defined. However, it is also possible to provide a braking system according to the invention which comprises another selection of the features defined above. According to a broad aspect of the invention, there is provided a braking system comprising an axle, a support member mounted to the axle, a brake ring connected to the outside of the support member, and a brake caliper for applying braking force to the brake ring. It further includes one or more of the following features:

(i) the brake ring is connected to the support member such that a conductive heat flow passage conducts heat from the brake ring to the support member;

(ii) there is an air flow passage through the support portion and the area in which the brake caliper is installed for heat transfer by convection from the brake ring and the brake caliper;

(iii) the support member is part of a wheel;

(iv) the braking system includes airflow generating means for producing a flow of air along the airflow passage;

(v) the brake ring is integrally formed with the support member;

(vi) the brake ring is planar and in a plane perpendicular to the axis of rotation of the axle;

(vii) The braking system includes a refrigerant system for cooling the braking system.

The braking system according to the broad aspect of the present invention may further incorporate any of the other features defined above.

The braking system can now be used in a wide variety of applications, including but not limited to a variety of vehicles. Examples of the present invention, including automobiles, trains, and aircraft, including racing cars, are described below.

By way of example, embodiments of the invention will be described with reference to the accompanying schematic drawings.

1 is a vertical sectional view of a braking system applied to a conventional automobile wheel;

FIG. 2 is a perspective view from outside the vehicle wheel, which is a modified form of the wheel shown in FIG. 1; FIG.

3 is a perspective view from inside the wheel of FIG. 2 with a brake ring attached to the wheel;

4 is a cross-sectional view of an automotive wheel axle assembly with a modified form of braking system;

5 is a perspective view of a train axle with a braking system;

6 is a schematic perspective view of a braking system for a vehicle wheel, including a refrigerant system.

The motor vehicle wheel shown in FIG. 1 includes a fixing hole 1 for securing it to the axle of the vehicle and a rim 2 for receiving a pneumatic tire (not shown). It is generally the same as a conventional vehicle in that it has the support member 9 to make. However, it differs from the conventional vehicle in that it includes an annular brake ring 3 fixed to an annular recess 4 of the rim 2 by countersunk bolts 5. In addition, the support member 9 extending from the center of the wheel to the rim 2 is provided with many openings 10.

A braking force can be applied to the brake ring 3 using a caliper 6 attached to the suspension of the vehicle, and the braking force is hydraulically applied in a conventional manner via a hydraulic hose (not shown). Acting as a hydraulic piston, the hydraulic piston can be pushed into the brake pad 8 and frictional engagement of the brake pad 8 with the ring 3 is achieved.

In use, airflow passes through the brake caliper 6 and brake ring 3 and passes through the opening 10, which takes away heat generated during the braking from the parts. In addition, heat generated in the brake ring 3 flows to the rim portion of the support member 9 through the interface with the rim 2. The brake ring 3 and the rim 2 are connected around all the periphery of the wheel in the same way as the bolts 5 provided at intervals. Thus, a conductive heat flow passage is connected from the ring 3 to the support member 9.

In the particular embodiment shown, the cross-sectional area of the interface between the brake ring 3 and the support member 9 is as large as the cross-sectional area of the brake ring immediately upstream of the interface. Thus, if the ring 3 and the support member 9 are made of a thermally conductive material and there is a good thermal contact at the interface, a good conductive heat flow passage is formed, so that the brake ring In (3), heat is conducted to the support member (9). In the embodiment shown in FIG. 1, the opening 10 occupies about 90% of the cross-sectional area of the support member 9, thus passing through the region in which the brake caliper 6 is installed and the support member 9. There will be an air flow passage. As a result, heat transfer by convection from the brake ring 3 and the brake caliper 6 is facilitated. Preferably, the convection may be forced convection, for example by installing a vane over the support member such that an air flow passes through the opening 10, further increasing the convection. This is the case of the embodiment of FIG. 1, wherein the support member 9 comprises a vane 11.

Removing and replacing the wheel from the vehicle can be accomplished in a substantially conventional manner, i.e. loosening a part of the caliper 6 near the line AA so that the caliper can be moved to the position indicated by the dotted line in the figure After the next turn, remove and replace the retaining nut or bolt that holds the wheel on the vehicle axle.

The vehicle braking system according to the invention can be used in a variety of vehicles. The system can be used in road vehicles, for example automobiles, buses, vans and road trailer vehicles, and vehicles running on rails or tracks, for example railroad carriages, railroad wagons. And trams, and finally in aircrafts.

FIG. 2 shows a variant of a wheel that is generally similar to the wheel of FIG. 1, where the same reference numerals are used to indicate the parts. In FIG. 2, the brake ring 3 and the brake caliper 6 are not shown. The parts are shown in FIG. In addition, in Figures 2 and 3, the support member 9 is shown having vanes 11 which generate a flow of air (as indicated by the arrows in Figure 1) through the wheel.

In the embodiment shown in FIGS. 2 and 3, both the support member 9 and the brake ring 3 are made of aluminum, thermal conductor.

The advantage of providing the brake ring 3 makes it possible to add strength to the inner rim of the wheel, thereby reducing the thickness of the parts of the wheel.

Particularly in high performance motor vehicles, for example, a laser thermometer (not shown) monitors the temperature of the brake ring and / or brake pads, and the temperature signal is input as a controller to control the braking. It is preferable to use.

4 shows a modified device of a motor vehicle in which the braking system is mounted on the rear axle 23 of the vehicle away from the wheel. In the illustrated embodiment, the system is mounted on both sides of a differential or gearbox unit 20 equipped with a brake caliper 21 for each system. Each braking system is an open vaned element which is mounted on each axle 23 and extends outward and connected to the outside of the brake ring 3 on which the caliper 21 acts. 22). The vane support member 22 causes air flow in the region of the brake ring 3 and the caliper 21, and serves to cool the support member as a result of its fin-like structure. Do it. Arrows indicate the direction of air flow.

FIG. 5 shows a device similar to the device of FIG. 4, but applied to an axle of a railway vehicle having wheels 25 on rails 26. As in FIG. 4, the same reference numerals that refer to the parts are used in FIG. 5.

FIG. 6 schematically shows a braking system and a fluid cooling system of the kind shown in FIGS. 4 and 5. A sealed chamber 30 is installed in the region of the braking system, wherein the refrigerant is located between the chamber 30 and another heat exchange radiator 32 where the refrigerant is condensed and cooled. Circulated along a tube 31. 6 is a schematic view, it should be understood that the chamber 30 merely wraps the caliper, for example, and can be in sealing contact with the brake ring 3.

Claims (15)

A braking system comprising an axle, a support member mounted to the axle, a brake ring connected to the outside of the support member, and a brake caliper for applying braking force to the brake ring, wherein the brake ring has a conductive heat flow path in the brake ring. Connected to the support member, for conducting heat transfer by convection from the brake ring and the brake caliper, in which the brake caliper is installed and an air flow passage through the support member Breaking system, characterized in that. The braking system of claim 1, wherein the support member is part of a wheel. 3. The braking system according to claim 1 or 2, further comprising airflow generating means for producing a flow of air along the airflow passage. 4. The braking system as recited in claim 3, wherein said support member comprises vanes for creating a flow of air along said air flow passage. 5. The braking system according to claim 1, wherein the brake ring is detachably connected to the support member. 6. The braking system according to any one of claims 1 to 4, wherein the brake ring is formed integrally with the support member. 7. The braking system according to any one of the preceding claims, wherein the brake ring projects radially inward from the outside of the support member. 8. The braking system according to claim 7, wherein the brake ring is planar and in a plane perpendicular to the axis of rotation of the axle. A braking system comprising an axle, a support member mounted to the axle, a brake ring connected to the outside of the support member, and a brake caliper for applying braking force to the brake ring. (i) the brake ring is connected to the support member such that a conductive heat flow passage conducts heat from the brake ring to the support member; (ii) there is an air flow passage through the area in which the brake caliper is installed and the support member for heat transfer by convection from the brake ring and the brake caliper; (iii) the support member is part of a wheel; (iv) the braking system comprises airflow generating means for producing a flow of air along the airflow passage; (v) the brake ring is integrally formed with the support member; (vi) the brake ring is planar and in a plane perpendicular to the axis of rotation of the axle; (vii) the braking system further comprising one or more of the features that circulate a refrigerant system for cooling the braking system. 10. A braking system as claimed in any preceding claim, further comprising a refrigerant system for cooling the braking system. A vehicle comprising the braking system according to claim 1. 12. The vehicle according to claim 11, wherein said vehicle is a motor vehicle. 12. The vehicle according to claim 11, wherein said vehicle is a train. 12. The vehicle according to claim 11, wherein said vehicle is an aircraft. Substantially, a braking system as described with reference to it as shown in the accompanying drawings herein.

Images