DESC:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patent Rules, 2003
COMPLETE SPECIFICATION
(See sections 10 & rule 13)
1. TITLE OF THE INVENTION
A SYSTEM TO OPERATE ELECTRONIC BRAKE IN CONJUNCTION WITH MECHANICAL BRAKE LINKAGE IN CRAWLER DOZER
2. APPLICANT (S)
NAME NATIONALITY ADDRESS
BEML LIMITED IN BEML Soudha, No 23/1, 4th Main S.R. Nagar, Bengaluru- 560027, Karnataka, India.
3. PREAMBLE TO THE DESCRIPTION
COMPLETE SPECIFICATION

The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF INVENTION:
[001] The present invention relates to the field of bulldozer braking system. The present invention in particular relates to a system to operate electronic brake in conjunction with mechanical brake linkage in crawler dozer.
DESCRIPTION OF THE RELATED ART:
[002] Crawler dozer is basically off-highway equipment used for mining and construction activities like clearing overburden, uprooting trees, leveling uneven terrain etc. Crawler dozers are equipped with a blade at front for dozing operation and a ripper at rear end for ploughing operation. The prime mover is a diesel engine in general and the power produced by the engine is transmitted to the transmission through a damper, torque converter and universal joint. Transmission is a planetary gear mechanism with a hydraulic control unit for gear shifting. Power from transmission assembly is transmitted to left and right final drives through a bevel pinion, bevel gear and steering clutches.
[003] A proportionally controlled brake control valve which is installed to the brake clutch is controlling the oil pressure of the brake system. The proportional control valve enables easier and finite control of the oil pressure to the brake clutch. A smooth braking of the equipment is a mandatory requirement even for off-highway equipment for safe operation and a stress-free drive for the operator. The smooth braking can be achieved through electronic brake pedals. But for high end dozers working in non-uniform terrain, feather touch electronic brake pedals will create sudden brakes due to ground impact on operator feet.
[004] Reference may be made to the following:
[005] IN Publication No. 201841030487 relates to a braking system for a dozer comprising a brake pedal and a rod assembly. The brake pedal is linked with a brake lever by means of a brake linkage. The rod assembly is connected to a first lever, at one end, and the brake lever, at another end, thereby connected to the brake pedal. The rod assembly facilitates reduction of engine Revolutions per Minute (RPM) upon application of the brake pedal by pulling the rod assembly inwardly as a result of an outward push received by the brake linkage. Subsequently, a second lever via the first lever, is pushed to limit fuel flowing into a Fuel Injection Pump (FIP) when the brake pedal is pressed thereby bringing down the engine RPM below a predefined threshold.
[006] The above IN Publication No. 201841030487 claims a mechanical linkage system which controls the engine speed by controlling the fuel supply to fuel injection pump during the application of service brake. Whereas the present invention claims that providing the electro-mechanical data to the service braking system through electronic controller. This ensures the smooth and precise braking of equipment. Integration of mechanical brake pedal and angle sensor through linkages place a major role.
[007] Publication No. CN102839701 relates to a braking system of a bulldozer. The braking system comprises a steering clutch, a brake-type steering machine and a step less speed regulation hydraulic steering motor, wherein the steering clutch is connected with the brake-type steering machine, so that the pivot steering of a mechanism is realized, the radius of the steering range is small, and the steering is flexible; and the step less speed regulation hydraulic steering motor is connected with a speed-variable control lever, so that different steering radiuses and rotating speeds can be realized. The braking system of the bulldozer, provided by the invention, can be used for assisting a driver to easily control the driving, ensuring easiness in driving and high-standard safety function, and simultaneously realizing energy conservation and consumption reduction.
[008] The above Publication No. CN102839701 claims a brake steering system with a proportional hydraulic steering motor which will be operated with a speed change joystick for steering the equipment. Whereas the present invention claims that providing the electro-mechanical data to the service braking system through electronic controller. This ensures the smooth and precise braking of equipment. Integration of mechanical brake pedal and angle sensor through linkages place a major role.
[009] Publication No. CN215059339 relates to the technical field of mechanical bulldozers, in particular to an inertia brake, a gear shifting control system and a mechanical bulldozer, the inertia brake is of a hydraulic control structure, operation and adjustment are not needed, and the operation, installation, adjustment and maintenance processes are simplified. The gear shifting control system comprises a main clutch, a main clutch handle, a second control valve and the inertia brake, the second control valve is used for controlling combination and separation of a friction plate of the main clutch, a position sensor is arranged on the main clutch handle, and the position sensor, the first control valve and the second control valve are all electrically connected with the controller. The controller can control the first control valve and the second control valve according to a signal of the position sensor, so that the main clutch and the inertia brake can act according to a set sequence in the gear shifting operation process, the vehicle fault hidden danger caused by improper operation adjustment is avoided, the control process is intelligent and efficient, and the operation intensity is low.
[010] The above Publication No. CN215059339 claims an inertia braking system. Whereas the present invention claims that providing the electro-mechanical data to the service braking system through electronic controller. This ensures the smooth and precise braking of equipment. Integration of mechanical brake pedal and angle sensor through linkages place a major role.
[011] Publication No. CN104149849 relates to the technical field of hydraulic control components, in particular to a hydraulic steering brake system. Steering of a hydraulic control steering brake valve is controlled through a hydraulic pilot handle, a hydraulic pedal brake valve and a shuttle valve bank, the mode that steering of the steering brake is controlled through a mechanical connection rod and a flexible shaft is replaced, people only need to overcome resistance of the hydraulic pilot handle or a pedal of the hydraulic pedal brake valve during operation to achieve the work processes of sharp turning, little turning and emergent braking of a bulldozer, control force is obviously reduced, the operation comfort degree is improved, the structure is simple, installation space is saved, and time for debugging and installation is reduced. The invention further provides the hydraulic control steering brake valve which is an integrated valve formed by integrating a left steering valve, a right steering valve, a left brake valve body and a right brake valve body, and a pilot oil cavity is formed in a valve body and used for controlling moving of a valve element. The hydraulic control steering brake valve is simple and compact in structure, little in occupied installation space, and capable of lowering machining difficulty and machining cost.
[012] The above Publication No. CN104149849 claims a hydraulic control brake system with hydraulically controlled brake valve controlled through a mechanical brake pedal with control linkages. Whereas the present invention claims that providing the electro-mechanical data to the service braking system through electronic controller. This ensures the smooth and precise braking of equipment. Integration of mechanical brake pedal and angle sensor through linkages place a major role.
[013] IN Publication No. 202041012002 provides emergency braking system to perform barking operation when the engine is in off condition (emergency condition). The system comprises a steering pump configured to assist steering activity and a hydraulic braking circuit, at least one an accumulator configured for storing pressurized fluid, at least one check valve configured for suppling for pressurized fluid to the accumulator through tapped line from the hydraulic braking circuit; and at least one shuttle valve configured for actuating a brake booster by optionally switching the supply between the steering pump and the accumulator based on normal working system and emergency braking system respectively.
[014] The above IN Publication No. 202041012002 claims an emergency braking system when the engine is in OFF condition with the help of stored energy of hydraulic accumulator. Whereas the present invention claims that providing the electro-mechanical data to the service braking system through electronic controller. This ensures the smooth and precise braking of equipment. Integration of mechanical brake pedal and angle sensor through linkages place a major role.
[015] Publication No. CN218055148 relates to a parking brake release system for an electrically-driven bulldozer. The parking brake release system comprises a pilot pump; the parking brake control valve is provided with a first port, a second port and a third port, the first port is connected with the oil outlet of the pilot pump, the second port is connected with the hydraulic oil tank, and the third port is connected with the parking brake piston; the brake release sequence valve is provided with an oil inlet, a first oil outlet and a second oil outlet, the oil inlet is connected with the oil outlet of the working pump, the first oil outlet is connected with the working hydraulic system, and the second oil outlet is connected with a first port of the parking brake control valve. When parking braking needs to be relieved, the parking braking control valve is switched from the first position to the second position, the oil inlet of the braking relieving sequence valve is in fluid communication with the second oil outlet, and the first oil outlet is closed; and after parking braking is completely relieved, the oil inlet of the braking relieving sequence valve is in fluid communication with the first oil outlet, and the second oil outlet is closed. The utility model further relates to the electrically-driven bulldozer comprising the parking brake releasing system.
[016] The above Publication No. CN218055148 claims a parking brake release system for an electrically driven bulldozer which is hydraulically controlled requires pilot pump and solenoid valve. Whereas the present invention claims that service braking system of dozer is controlled through electro-mechanically.
[017] Publication No. CN214945908 relates to the technical field of bulldozer winches, solves the problems that when a belt-type brake device brakes, huge bending acting force is generated on a brake shaft, a brake belt is not uniformly abraded, the adjusting period is short and the maintenance cost is high, and comprises a bearing seat, a piston, a spring group, a brake drum, a pressure plate, an inner drum and a hub, during braking, the brake axle is uniform in stress, stable and reliable in performance, high in transmission efficiency, capable of providing large dragging force, low in maintenance cost, few in maintenance frequency, convenient to maintain and capable of working in a humid and hot environment for a long time, the slipping risk is reduced, safety is improved during winch operation, a host and an operator can be better protected, and the service life of the winch is prolonged. The device can be widely applied to the winch of the forest lumbering type bulldozer.
[018] The above Publication No. CN214945908 claims a wet type brake device for winches used in bulldozer. Whereas the present invention claims that providing the electro-mechanical data to the service braking system through electronic controller. This ensures the smooth and precise braking of equipment. Integration of mechanical brake pedal and angle sensor through linkages place a major role.
[019] Publication No. CN209258104 discloses an emergency braking system of a bulldozer. The emergency braking system of the bulldozer comprises a hydraulic pump, a steering valve, a brake linkage valve and a brake booster, the hydraulic pump is connected with the brake booster through the steering valve and the brake linkage valve. Wherein a brake loop is formed among the hydraulic pump, the steering valve, the brake linkage valve and the brake booster, the brake booster is connected with a brake rocker arm of the bulldozer, the emergency brake system of the bulldozer further comprises an emergency assembly and the emergency assembly is connected with the brake booster. According to the technical scheme that the emergency assembly is additionally arranged in the braking loop of the system, when an engine flames out accidentally, the emergency assembly converts hydraulic energy into mechanical energy, it is guaranteed that the system can have the braking capacity in a short time, on-site requirements are met, and fault hidden dangers are eliminated.
[020] The above Publication No. CN209258104 claims a parking brake release system for a bulldozer which is hydraulically controlled requires pilot pump and direction control valve which controls through linkages. Whereas the present invention claims that service braking system of dozer is controlled through electro-mechanically.
[021] Publication No. CN108166560 discloses a bulldozer steering and braking control method. The bulldozer steering and braking control method comprises the following steps: in the steering process, a steering proportional valve is electrified at t0 time, and the current value is gradually increased to a first preset value along with time between the t0 time and t4 time; the current of a braking proportional valve is gradually reduced to a second preset value between t2 time and t5 time; a braking clutch comprises a braking combination beginning point t3 between the t2 time and the t5 time; and a steering clutch friction plate is totally separated before the braking combination beginning point t3, wherein t0 is not more than t2 less than t3 less than t5. The problem of influence on the steering operation comfort by high steering and braking impact due to high combination speed of the steering clutch friction plate and a braking clutch friction plate in the electric control steering and braking process of a bulldozer is solved.
[022] The above Publication No. CN108166560 claims an automatically programmed steering and brake control based on time intervals. Whereas the present invention claims that providing the electro-mechanical data to the service braking system through electronic controller. This ensures the smooth and precise braking of equipment. Integration of mechanical brake pedal and angle sensor through linkages place a major role.
[023] Earlier braking system consists of a feather touch electronic brake pedal which will give an electric output to the steering and brake controller and in turn controls a brake valve and stop the vehicle. Since the bulldozer is working in a highly non uniform terrain, the ground impacts will transfer to the operator foot through the brake pedal and the operator will not be able to control the pedal operation. Thereby this causes sharp braking or uncontrolled braking.
[024] For high end bulldozers working in an open cast mine, where terrain is uneven and slushy, the ground impacts which are transferring to the operator is very high. Operating a smooth and feather touch control like electronic brake pedals will be challenging task for the precise and smooth operation of the equipment. The above task will be having a direct impact on the production as well as the safety of the working personals. Smooth brake pedal can cause sudden impacts and it will create sharp or sudden braking of the equipment and it may lead to premature failure of many critical components. Also, it will create physical stress to the equipment operator. Hence there needed an improved braking system having a smooth braking.
[025] In order to overcome above listed prior art, the present invention aims to provide a system to operate electronic brake in conjunction with mechanical brake linkage in crawler dozer.
OBJECTIVES OF THE INVENTION:
[026] The principal objective of the present invention is to provide a system to operate electronic brake in conjunction with mechanical brake linkage in crawler dozer.
[027] Another objective of the present invention is to provide a brake pedal is rigid enough to give proper balance and control for the operator.
[028] Yet another objective of the present invention is to provide electronic brake pedal with direct connection to controller through wire harness to provide smooth brake functioning.
SUMMARY:
[029] The present invention relates to the system to operate electronic brake in conjunction with mechanical brake linkage in crawler dozer. The present brake pedal is rigid enough to give proper balance and control for the operator. Smooth braking will happen through proportional control using angle sensor, controller and proportional control valve.
BREIF DESCRIPTION OF THE INVENTION
[030] It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments.
[031] Figure 1 (a) shows system to operate electronic brake in conjunction with mechanical brake pedal and linkage in crawler dozer;
[032] Figure 1 (b) shows feather touch electronic brake pedal;
[033] Figure 2 shows flowchart according to the present invention;
[034] Figure 3 shows part details pertaining to the system.
DETAILED DESCRIPTION OF THE INVENTION:
[035] The present invention provides a system to operate electronic brake in conjunction with mechanical brake linkage in crawler dozer. The present brake pedal is rigid enough to give proper balance and control for the operator. Smooth braking will happen through proportional control using angle sensor, controller and proportional control valve.
[036] Referring to fig 3, the system comprises brake pedal (1), retainer spring assembly (2), control linkages (3), angle sensor (4), controller and brake control valve. The mechanical brake pedal mounted with high stiffness holding spring integrated with electronic angle sensor for converting the mechanical movement to electric current which gives signal to an electronic controller. The controller actuates brake control valve proportionally to get a smooth braking.
[037] The linkage mechanism in conjunction with angle sensor (potentiometer) for the operation of main brake for crawler dozer is shown in the sketch. The mechanism consists of brake pedal, retainer spring assembly, linkage, angle sensor and wire harness. The brake pedal (1) is mounted on the operator cabin floor with needle roller bearings for smooth rotation. Necessary stopper mechanism is provided for the required angular movement of the pedal. The pedal is held against a retainer spring assembly (2) which will decide the effort to operate the brake pedal. A mechanical control linkage (3) is provided to connect brake pedal with angle sensor lever which will rotate the angle sensor shaft (4). Specified rotation angle of angle sensor shaft will generate maximum voltage output for effective proportional braking. The output current is supplied to the controller through wire harness and the controller will operate the brake control valve.
[038] Proportionally controlled brake control valve installed to brake clutch controls the oil pressure of brake system. The proportional control valve enables easier and infinite control of the oil pressure to brake clutch. It streamlines the oil pressure to the system to get the desired performance through ECU (fig 2).
[039] The advantages of the system are:
1. Sturdy brake pedal and smooth operations.
2. Less operator fatigues.
3. Compact, less maintenance and better serviceability.
[040] Thus, the braking system is improved by introducing sufficient effort on the operator leg so that ground shocks cannot affect the braking unless until the operator puts sufficient effort by himself to initiate the braking. But the steering and brake controller needs an electric output for its function. Therefore, a spring controlled sturdy mechanical brake pedal integrated with an angle sensor which gives an electric output is designed and which will solve the above problem without any complicated system. This system works on electrical output against the operator effort.
[041] Numerous modifications and adaptations of the system of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations which fall within the true spirit and scope of this invention.
,CLAIMS:WE CLAIM:
1. A system to operate electronic brake in conjunction with mechanical brake linkage in crawler dozer comprises brake pedal (1) with control linkages (3), and brake control valve characterized in that pedal mounted with high stiffness retainer spring assembly (2), integrated with electronic angle sensor (4), for converting the mechanical movement to electric current which gives signal to an electronic controller which actuates brake control valve proportionally to get a smooth braking.
2. The linkage mechanism in conjunction with angle sensor (potentiometer) for the operation of main brake for crawler dozer is shown in the sketch. The mechanism consists of brake pedal, retainer spring assembly, linkage, angle sensor and wire harness. The brake pedal (1) is mounted on the operator cabin floor with needle roller bearings for smooth rotation. Necessary stopper mechanism is provided for the required angular movement of the pedal. The pedal is held against a retainer spring assembly (2) which will decide the effort to operate the brake pedal. A mechanical control linkage (3) is provided to connect brake pedal with angle sensor lever which will rotate the angle sensor shaft (4). Specified rotation angle of angle sensor shaft will generate maximum voltage output for effective proportional braking. The output current is supplied to the controller through wire harness and the controller will operate the brake control valve.
3. The system to operate electronic brake in conjunction with mechanical brake linkage in crawler dozer, as claimed in claim 1, wherein the Proportionally controlled brake control valve installed to brake clutch controls the oil pressure of brake system which enables easier and infinite control of the oil pressure to brake clutch and streamlines the oil pressure to the system to get the desired performance through control unit.
4. The system to operate electronic brake in conjunction with mechanical brake linkage in crawler dozer, as claimed in claim 1, wherein the smooth braking will happen through proportional control using angle sensor, controller and proportional control valve.