DESC:Field of the invention

The present invention relates to a pneumatic braking system. More particularly, the present invention relates to a system for reducing temperature of compressed air used in a pneumatic braking system for efficient working of the pneumatic system.

Background of the invention

Generally, compressed air from a compressor is passed through an air treatment and control unit, here after called as an airtrec towards pneumatic operating elements. The airtrec removes moisture from the air to enable the pneumatic braking system to work efficiently. The delivery temperature of the compressed air in the pneumatic braking system is at about more than 100 degrees Celsius. Drying performance of the airtrec depends on delivery temperature of the compressed air. Specifically, the dryer performs efficiently, if the air temperature is at about 65- 70 degree Celsius. In existing technology, a metal pipe of approximately 5 meters in length is used, which enables heat dissipation. The metal pipe connects a compressor to the airtrec thereby allowing ingress of the compressed air in the pneumatic braking system.
However, when the vehicle tonnage capacity increases due to demand, achieving the temperature drop from the compressor to the airtrec inlet by using the metal pipe of 5-meter length becomes difficult. At higher temperature, the airtrec does not work efficiently, thereby leaving behind some moisture in the air. The moisture corrodes end components, such as metal and ferrous mixed components of the pneumatic braking system thereby reducing life of the components.
Therefore, there is a need to provide a system and method for reducing temperature of compressed air used in pneumatic system, which can overcome at least some of the above mentioned drawbacks of the prior art and reduce temperature of the compressed air in the pneumatic system to a desired temperature range.

Objects of the invention

Object of the present invention is to provide a system and for reducing temperature of compressed air in a pneumatic braking system.

Another object of the present invention is to provide a system for reducing temperature of compressed air in the pneumatic braking system thereby improving drying efficiency of an air treatment and control unit (airtrec).

Another object of the present invention is to provide a system for reducing temperature of compressed air in the pneumatic braking system thereby reducing corrosion of the components of the pneumatic braking elements.

Still another object of the present invention is to provide a system for reducing temperature of compressed air in the pneumatic braking system, which is economical and can be operated easily.

One more object of the present invention is to provide a system for reducing temperature of compressed air in the pneumatic braking system, which is easy to manufacture.

Summary of the invention:

According to present invention a system for reducing temperature of compressed air used in a pneumatic braking system of vehicles is provided. The system includes at least one heat dissipater arranged between an air compressor and an air treatment and control unit (airtrec). The heat dissipater dissipates the heat of the received hot compressed air from the air compressor to the atmosphere. The cooled or treated air compressed air is supplied to the airtrec, thereby increasing drying efficiency, life of the components of the airtrec by reducing corrosion.

Brief Description of drawings

The advantages and features of the present invention will become better understood with reference to the following detailed description taken in conjunction with the accompanying drawings, wherein like elements are identified with like symbols, and in which:

Figure 1 shows a circuit diagram of a system for reducing temperature of compressed air used in pneumatic braking system, with an air treatment and control unit (airtrec) and an air compressor in accordance with the present invention;
Figure 2a shows a front view of a heat dissipater of the system in accordance with the present invention;
Figure 2b shows a top view of the figure 2a;
Figure 2c shows a side view of the figure 2a;
Figure 3 shows an isometric view of the figure 2a; and
Figure 4 shows probable locations for mounting the heat dissipater of figure 2a in accordance with the present invention.

Detail description of the invention

An embodiment of this invention, illustrating its features, will now be described in detail. The words "comprising," "having," "containing," and "including," and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items.

The terms “first,” “second,” and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another, and the terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.

The disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms.

The present invention is a system for reducing temperature of compressed air in a pneumatic braking system. The system improves drying efficiency of an air treatment and control unit (airtrec) in the pneumatic braking system by reducing temperature of the compressed air in the desired range, thereby reducing corrosion of the components of a pneumatic braking system. Furthermore, the system is economical and can be operated easily.

Referring now to figure 1, a system 1000 and method for reducing temperature of compressed air in a pneumatic braking system in accordance with the present invention is illustrated. In the present embodiment, the system 1000 comprises at least one heat dissipater 100 with elements being adapted for the pneumatic braking system. In the present embodiment, one heat dissipater 100 is used in a pneumatic braking system of a vehicle and is mounted between an air compressor 200 and an airtrec 300 of the pneumatic braking system. Furthermore, the heat dissipater 100 can be used for any other pneumatic application.

Specifically, figure 1 shows a pneumatic circuit of the airtrec 300 in the brake system of the vehicle along with a heat dissipater 100 and the air compressor 200. The system 1000 comprising at least one heat dissipater 100 arranged between the air compressor 200 and the airtrec 300 for reducing temperature of the compressed air by dissipating heat of the compressed air to the atmosphere. The hot compressed air from the air compressor 200 is delivered to the heat dissipater 100. The heat of hot compressed air is dissipated to atmosphere by the heat dissipater 100. The heat dissipater 100 supplies cold or treated compressed air to the airtrec 300. The airtrec 300 includes a cartridge unit 31, non-return valves 32, 43, 44, a Governor valve 33, a cylinder head unloading 34, a pressure switch 35, a Solenoid valve, 2x2 Normally closed type with inbuilt time delay 36 and 45, an Un-loader valve 37 with Silencer 38, and a four protection valves 39, 40, 41, and 42, two of which protection valves being connected to Primary and Secondary reservoirs.

The pneumatic circuit of the airtrec 300 as shown in figure 1 is used for three working cycles like charging cycle, regeneration cycle and un-loading cycle. These cycles are described in detail below:

1. Charging cycle:
During charging cycle compressed air flows directly to the cartridge unit through the heat dissipater 100 from the air compressor 200. In charging cycle, the cartridge unit 31 converts moist air to dry air. Further path of dry air is equally supplied to a governor valve portion 33 and a protection valve circuit portion 39 and 40. When air pressure in the system reaches a desired pressure limit (cut out pressure), the governor valve 33 provides pneumatic signals to pressure switch 35 and another pneumatic signal to a cylinder head 34 of compressor for un-loading.
The protection valve circuit has four protection valves 39, 40, 41 and 42, which are spring-operated valves. Based on set pressure of spring, protection valves distribute dry air to a primary reservoir 21 and a secondary reservoir 22 and to a first path 23 and a second path 24 of the pneumatic braking system.

2. Regeneration cycle:
When the pressure switch 35 gets the signal from governor valve 33, the switch 35 provides electric signal to solenoid valve 45. Here solenoid valve is 2x2 normally closed versions with integrated time delay function 36. During regeneration cycle, reservoir dry air from the primary reservoir 21 and the secondary reservoir 22 flow back to the cartridge unit 31 thorough the solenoid valve 45. This dry air absorbs or removes the moisture and other impurities like oil and carbon particles etc. from desiccant, which is adsorbed during charging mode. Further, this contaminated air flows to atmosphere through silencer 38.

3. Unloading cycle:
When un-loader valve 37 receives pneumatic signal from the governor valve 33, it exerts force on an un-loader plunger. Due to the un-loader plunger movement, closed position is opened to the atmosphere. When valve gets opened, air supply to the airtrec 300 and the cartridge unit 31 is connected to exhaust through the silencer assembly 38 until pneumatic brake system reaches cut in (falling of system pressure due to consumption reservoir pressure during braking) condition.

Referring now to figures 2a, 2b and 2c, the heat dissipater 100 comprises an ingress port 48, a plurality of tubes 50, a frame 60, an egress port 70 and an attaching member 80. The ingress port 48 is connected to the outlet (not shown in figure) of the air compressor 200. The ingress port 48 receives hot compressed air from the air compressor 200 and supplies to the plurality of tubes 50. The outer surface of the plurality of tubes 50 is exposed to the atmosphere. The plurality of tubes 50 is made of aluminium. The plurality of tubes 50 may also be made of copper or silver or any material having high thermal conductivity. The received hot compressed air from the ingress port 48 is distributed among each of the plurality of the tubes 50. The heat of the hot compressed air is transferred to the outer surface of the plurality of the tubes 50 by conduction. Hot compressed air is cooled as heat is dissipated from the plurality of tubes 50. Atmospheric air circulates over the outer surface of the plurality of tubes 50. The heat of the plurality of tubes 50 is dissipated to atmospheric air by convection. So, the outer surface of the plurality of tubes is cooled. Same cycle of heat transfer is repeated continuously. The cooled or treated compressed air collects at the egress port 70. The egress port 70 is connected to the inlet of the airtrec 300.The egress port 70 receives cooled or treated air from the plurality of tubes 50 and supplies cooled air to the airtrec 300. The frame 60 supports the plurality of tubes 50, thereby to attach the heat exchanger 100 to a chassis 500 (shown in fig 4) of the vehicle through the attaching member 80. The plurality of tubes 50 can be brazed to the frame 60. The attaching member 80 can be a mounting clip or a fastener or a rivet or any other attaching member which is obvious to person skilled in the art. The frame 60 can be attached to the chassis 500 of the vehicle by a welding, bolt or rivet.

The efficiency of the heat dissipater 100 depends on atmospheric temperature, total outer surface area of the plurality of tubes 50, and air velocity. For a better efficiency the heat dissipater 100 can be exposed to the atmosphere whose temperature is less. In order to expose the heat dissipater 100 to the cool atmosphere, the heat dissipater 100 may be configured away from or next to the engine compartment in case of the automobile depending upon the environmental factor. The heat dissipater 100 should be away from an exhaust (not shown) of an engine (not shown) of the vehicles. In addition, the heat exchanger 100 can be located on long members and cross member of the vehicle middle zone, as shown in figure 4. A proper method is adopted to identify a proper location for positioning the heat dissipater 100 on the vehicle.

Further, the efficiency of the heat dissipater 100 can be improved by increasing total outer surface area of the heat dissipater 100. To increase the total outer surface area of the heat dissipater 100, a plurality of fins (not shown) is configured on outer surface of each of the plurality of tubes 50. The surface of the each of plurality of fins is coated with a protective coating. The protective coating is having high thermal conductivity. The plurality of fins is in chevron or “V” shape. The outer surface of each of the plurality of fins is exposed to the atmosphere for heat dissipation. The outer surface of each of the plurality of fins is not in contact with the another surface of the other fin of the plurality of fins.

Furthermore, the efficiency of the heat dissipater 100 can be improved by increasing air velocity. Air velocity here refers to the velocity of air which circulates over the outer surface of the plurality of tubes 50 or the outer surface of the plurality of fins. The velocity of atmospheric air which is contact with the outer surface of the plurality of tubes 50 is directly proportional to the speed of vehicle. Under this condition atmospheric air gets velocity without external assistance. To further improve the velocity of air an external device can be used. The device can be a nozzle or a fan or an impeller or any other device which increases velocity of air at the outer surface of the plurality of tubes 50 which is obvious to person skilled in the art.

For supplying continuous and more amount of cool compressed air more than one heat dissipater 100 can be adopted in the system 1000. The arrangement of the heat dissipater 100 can be made based on availability of the space in vehicles, cost of the heat dissipater 100, flow of atmospheric air over the surface of heat dissipater 100 etc.

The system 1000 reduces the temperature of compressed by dissipating heat of hot compressed air to the atmosphere by the heat dissipater 100 and supplies cooled/ treated compressed air to the airtrec 300, which used in pneumatic braking system. The system 1000 has an advantage of for reducing temperature of compressed air used in pneumatic braking system thereby to improve drying efficiency of the airtrec 300. Further, the system 1000 reduces corrosion of the parts of the pneumatic braking system by reducing temperature of the compressed air, thereby increases the life of components which are present in the pneumatic braking system such as canister, casings, mesh, brake chamber, pushrod etc. Furthermore, the system 1000 is economical and can be operated easily. Moreover, the system 1000 is easy to manufacture and is robust in construction.

The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention.
,CLAIMS:We Claim:

1. A system for reducing temperature of compressed air used in a pneumatic braking system of vehicles, the pneumatic braking system includes:
an air compressor for compressing and supplying compressed air;
an air treatment and control unit (airtrec) for receiving air from the air compressor and removing moisture in the compressed air to deliver dried compressed air to the braking elements;
wherein the system comprising at least one heat dissipater arranged between the air compressor and the airtrec for reducing temperature of the compressed air by dissipating heat of the compressed air to the atmosphere.

2. The system as claimed in claim 1, wherein each of the heat dissipater comprising;
an ingress port for receiving hot compressed air from the air compressor;
a plurality of tubes for receiving compressed hot air from the ingress port, the plurality of tubes is exposed to atmosphere;
a frame for supporting the plurality of tubes therein to attach to a chassis of the vehicles; and
an egress port for receiving cooled compressed air from the plurality of tubes to be delivered to the airtrec.
.
3. The system as claimed in claim 2, wherein the plurality of tubes is made of aluminium.

4. The system as claimed in claim 2, wherein each of the heat dissipater comprising a plurality of fins configured on outer surface of each of the plurality of tubes.

5. The system as claimed in claim 4, wherein the plurality of fins is in chevron shape.

6. The system as claimed in claim 4, wherein the plurality of fins is coated with a protective coating.

7. The system as claimed in claim 2, wherein the frame is attached to the chassis of the vehicle by a fastener, such as rivets or mounting clip or welding.

8. The system as claimed in claim 2, where in flow path from supply to delivery is “U” type.

9. The system as claimed in claim 1, wherein a nozzle is attached near to the each of the heat dissipater to increase the flow of air over the surface of the heat exchanger.

10. The system as claimed in claim 1, wherein at least one fan is attached near to the each of the heat dissipater to increase the flow of air over the surface of the heat exchanger.