DESC:AN EMERGENCY BRAKE CONTROL SYSTEM TO APPLY BRAKE DURING EMERGENCY
FIELD OF INVENTION:
[001] The present subject matter described herein, relates to air brake system for motor grader. The present subject matter, in particularly, relates to an emergency brake control system in existing air brake system to apply brake during emergency condition.
BACKGROUND AND PRIOR ART AND PROBLEM IN PRIOR ART:
[002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[003] Motor graders are used in construction and mining sites for various applications. Small and mid-sized work blade graders like 10 Ft and 12 Ft are used in applications like material spreading, moving rolling, mixing and grading operations in road making construction fields. Larger size work blade graders like 16Ft are used mainly in various surface opencast mines for making the roads on which heavy trucks and dumpers are transporting coal and other minerals extracted from the earth.
[004] In motor graders air operated brake system is preferred for its easy serviceability, low cost and effective braking. Air operated brake system meets the ISO 3450- wheeled earth moving machinery performance requirements and test procedures for brake system. Four service brakes at tandem wheels used to slow down and stopping. Dry-disc parking brake at transmission output used for parking application.
[005] Referring to Figure 1 illustrating a conventional air operated brake system 100 for motor graders. The conventional air operated brake system 100 comprises an air compressor 101, a condenser 102, an unloader valve 103, a wet tank 104, a system protection valve 105, a non-return valve 106, a pair of service tank 107, a dual brake valve 108 and a pair of relay valves 109.
[006] The air compressor 101 is driven by engine to deliver compressed air to the air brake system 100. The unloader valve 103 is provided as a safety valve to relieve the pressure from the air brake system 100 when the pressure airline increases a predetermined limit. The condenser 102 is provided in the air brake system 100 to remove the moisture from the compressed air. The unloader valve 103 is provided between the air compressor 101 and the condenser 102. The moisture in the air brake system 100 is collected in wet tank 104. An automatic drain valve is provided at the bottom of the wet tank 104 to remove the moisture from the air brake system 100.
[007] Distribution of air in the air brake system 100 and safety is ensured by the system protection valve 105. The non-return valve 106 are provided at each output lines of the system protection valve 105 to protect the overall system damage due to leak or damage in independent lines. Generally, system protection valve 105 has one input and four output lines.
[008] Out of four output lines, two output lines are directed to the service tanks 107 that supply the air to brake chamber, one output line is used for parking brake actuation and one output line for utility like horn. Application and release of brake is initiated by dual brake valve 108 through foot operated pedal. The dual brake valve 108 has two input lines from the service tanks 107 and two output lines to the relay valves 109.
[009] Relay valves 109 are required in air brake system 100 to reduce the brake lag. Due to the longer length of the heavy vehicles, the air take little more time to travel from the dual brake valve 108 to the brake chamber. To avoid the delay in actuation, the relay valves 109 are recommended to mounted near the brake chamber. Also relay valves 109 draw required air from the corresponding service tanks 107 and actuates the brake chamber once the signal received from the dual brake valve 108. Each relay valve 109 has two output line to actuate the diagonal brakes. The diagonal cross brakes ensure the safe braking when one line fails. A stop light switch sensor 110 is mounted in the output lines of the relay valves 109 for indication by red light signal. At the time of actuation air from the relay valves 109 push the brake piston inside the tandem against the springs and holds the wet multiple brake discs inside which brings the vehicle to stop.
[0010] The spring applied air released type brake is used for parking application. In the vehicle OFF condition, due to the spring force, the parking brake will be in applied condition only. when engine starts, the compressor builds the air inside the system 100. The air pressure force exceeds the spring force in the parking brake chamber, which leads to release of parking brake. When parking brake is operated from inside the cabin, the parking brake solenoid energizes and cut the air supply to the parking brake chamber. Due to the lack of air pressure force, spring force comes in to action that leads the parking brake to applied condition. This fool-proof safe parking brake avoids the accidents due to insufficient air. The non-return valve 106 in the parking brake line used to release the parking brake by external air supply to move the equipment when complete air system fails / equipment break down condition.
[0011] Hence, there is a need of an emergency brake control system to integrate with the existing air brake system by introducing the graduated hand control valve inside the operator cabin when the main line air pressure goes below prescribed minimum, due to damage or leak.
[0012] If there is significant air leak during equipment operation, parking brake cannot be used to stop the equipment. In such case, sufficient air pressure may not be available to stop the equipment. To handle this type of emergency condition, the present invention proposes an emergency brake control system to apply brake during emergency.
[0013] The information disclosed in this background of the disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
OBJECTS OF THE INVENTION:
[0014] It is therefore the object of the present subject matter to overcome the aforementioned and other drawbacks in prior method/product/apparatus.
[0015] The principal objective of the present subject matter is to develop an emergency brake control system of air brake system which stop motor grader when foot pedal mechanism malfunctions.
[0016] Another object of the present subject matter is to develop an emergency brake control system of air brake system which uses existing air supply to apply brake.
[0017] Another object of the present subject matter is to develop an emergency brake control system of air brake system to increase the operator confidence during equipment operation.
[0018] Another object of the present subject matter is to develop an emergency brake control system of air brake system to ensure safety when main line air pressure drops below prescribed limit.
[0019] Another object of the present subject matter is to develop an emergency brake control system to apply brake automatically during emergency condition.
[0020] Another object of the present subject matter is to develop an emergency brake control system having operator controlled emergency brake withhold option
[0021] Yet another object of the present subject matter is to develop an emergency brake control system of air brake system to facilitate visual inspection by walk around for observation when engine is in running condition.
[0022] These and other objects and advantages of the present subject matter will be apparent to a person skilled in the art after consideration of the following detailed description taken into consideration with accompanying drawings in which preferred embodiments of the present subject matter are illustrated.
SUMMARY OF THE INVENTION:
[0023] Solution to one or more drawbacks of existing air brake system, and additional advantages are provided through the present emergency brake control system in air brake system as disclosed in the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be a part of the claimed disclosure.
[0024] According to a preferred embodiment, the present emergency brake control system comprises a compressor to deliver compressed air to the emergency brake control system, a condenser to remove the moisture content from the compressed air delivered by the compressor, an unloader valve, provided in between the compressor and the condenser, to relieve excess pressure in the air brake system, a wet tank having an automatic drain valve at the bottom of the wet tank to collect the moisture in the compressed air before delivering the compressed air to rest of the air brake system and emergency brake control system, a graduated hand control valve connected to the wet tank via an emergency brake line to apply the emergency brake when the main line air pressure goes below prescribed minimum due to damage or leak, a pair of emergency relay valves connected to brake chamber to avoid delay in application of brake, wherein the pair of emergency relay valves takes air from corresponding service tanks and actuate the brake chamber when signal is received from the graduated hand control valve.
[0025] In an aspect, each emergency relay valve has two output lines to actuate diagonal brake.
[0026] In an aspect, each emergency relay valve has one extra input emergency port.
[0027] In an aspect, the airline length between the compressor and the unloader valve depends on the compressor.
[0028] In an aspect, the pair of emergency relay valve apply the emergency brake through tandem service brakes.
[0029] In an aspect, the graduated hand control valve is provided in the operator cabin.
[0030] In an aspect, the emergency brake control system uses no external air supply.
[0031] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods or structure in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:
[0033] Fig. 1 illustrates a conventional air brake system without emergency brake; and
[0034] Fig. 2 illustrates an emergency brake control system in air brake system according to one of the embodiment of present subject matter.
[0035] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0036] While the embodiments of the disclosure are subject to various modifications and alternative forms, specific embodiment thereof have been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.
[0037] The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a device, system, assembly that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a system or device proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or device.
[0038] Referring to Figure 2 illustrating an emergency brake control system 200 in air brake system according to one of the embodiment of present subject matter. The emergency brake control system 200 comprises an air compressor 101, a condenser 102, an unloader valve 103, a wet tank 104, a graduated air control valve 201 and a pair of emergency relay valves 202.
[0039] The present emergency brake control system 200 is an additional system provided along with the conventional air brake system in motor graders. The emergency brake system 200 uses existing air compressor 101, condenser 102, unloader valve 103 and wet tank 104 of the air brake system 100 to drive the emergency brake control system 200. In addition to the existing components, a graduated hand control valve 201 and a pair of emergency relay valves 202 are provided in the emergency brake control system 200.
[0040] The air compressor 101 delivers compressed air to the emergency brake control system 200. Before delivering the compressed air to the emergency brake control system 200, the condenser 102 removes the moisture content from the compressed air delivered by the compressor 101. The unloader valve 103 is provided between the compressor 101 and the condenser 102 to relieve excess pressure in the air brake system. The moisture in the emergency brake control system 200 is collected in wet tank 104. An automatic drain valve is provided at the bottom of the wet tank 104 to remove the moisture from the emergency brake control system 200.
[0041] Distribution of air in the emergency brake control system 200 and safety is ensured by the system protection valve 105. The non-return valves 106 are provided at each output lines of the system protection valve 105 to protect the overall emergency brake control system 200 from damage due to leak or damage in independent lines. Generally, system protection valve 105 has one input and four output lines.
[0042] Out of four output lines, two output lines are directed to the service tanks 107 that supply the air to the emergency brake control system 200, one output line is used for parking brake actuation and one output line for utility like horn. Application and release of emergency brake is initiated by the graduated hand control valve 201. The graduated hand control valve 201 is connected to the wet tank 104 via an emergency brake line to apply the emergency brake. Further, the graduated hand control valve 201 is provided in the operator cabin to facilitate application of emergency brake when emergency situation arises, such as, pressure in the main line air going below prescribed minimum due to damage or leak.
[0043] The dual brake valve 108 has two input lines from the service tanks and two output lines to the emergency relay valves 202. Emergency relay valves 202 have one extra input port called emergency port apart from all other input and delivery ports of regular relay valve 109. This emergency port has been given input from the main wet tank 104. This emergency line always should have an air supply. If the air supply drops due to leak or if operator controls through graduated hand control valve 201, diaphragm inside the emergency relay valves 202 will allow the air from the service tanks 107 to push the brake piston through delivery ports.
[0044] If there is significant air leak during equipment operation, parking brake cannot be used to stop the equipment. In such case, sufficient air pressure may not be available to stop the equipment. To handle this type of emergency condition, if the air pressure drops below prescribed limit in the main supply line, proposed emergency brake system 200 will apply the brakes automatically using the air available at service tank 107 reservoirs. To enable operator controlled emergency brake withhold option, graduated hand control valve 201 is introduced in the emergency line. During engine running condition, if the operator needs to walk around for inspection of the equipment, he can apply the emergency brake by operating graduated hand control valve 201. Till he releases the emergency brake, equipment brake will be in applied condition only.
[0045] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
[0046] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature
,CLAIMS:We claim:
1. An emergency brake control system (200) to apply brake during emergency, the emergency brake control system (200) comprises:
an air compressor (101) to deliver compressed air to the emergency brake control system (200);
a condenser (102) to remove the moisture content from the compressed air delivered by the compressor (101);
an unloader valve (103), provided in between the compressor (101) and the condenser (102), to relieve excess pressure in the air brake system (100);
a wet tank (104) having an automatic drain valve at the bottom of the wet tank (104) to collect the moisture in the compressed air before delivering the compressed air to rest of the air brake system (100) and emergency brake control system (200);
a graduated hand control valve (201) connected to the wet tank (104) via an emergency brake line to apply the emergency brake when the main line air pressure goes below prescribed minimum due to damage or leak; and
a pair of emergency relay valves (202) connected to brake chamber to avoid delay in application of brake, wherein diaphragm inside the pair of emergency relay valves (202) takes air from corresponding service tanks (107) and actuate the brake chamber when signal is received from the graduated hand control valve (201).

2. The emergency control brake system (200) as claimed in claim 1, wherein each emergency relay valve (202) has two output lines to actuate diagonal brake.

3. The emergency control brake system (200) as claimed in claim 1, wherein each emergency relay valves (202) have one extra input emergency port.

4. The emergency control brake system (200) as claimed in claim 1, wherein the airline length between the compressor (101) and the unloader valve (103) depends on the compressor (101).

5. The emergency control brake system (200) as claimed in claim 1, wherein the pair of emergency relay valve (202) apply the emergency brake through tandem service brakes.

6. The emergency brake control system (200) as claimed in claim 1, wherein the graduated hand control valve (201) is provided in the operator cabin.

7. The emergency brake control system (200) as claimed in claim 1, wherein the emergency brake control system (200) uses no external air supply.