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 BOOM SAFETY DEVICE FOR PIPE LAYER
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 pipelayer machine. The present invention in particular relates to a boom safety device for pipe layer machine and its method of operation.
DESCRIPTION OF THE RELATED ART:
[002] Pipe layer is off-highway equipment used for operation in pipeline laying projects, construction sites and in open cast mines for conveyor track shifting etc. Pipe layers are equipped with a side boom fitted with a forged type adjustable hook. The hook can be lowered/ raised at different speeds easily through wire ropes driven by hydraulic winches. The main function of the pipe layer is to handle a load at different boom overhang positions and carry it over long distances in the uneven and slushy mine sites. The machine is fitted with side boom & the load is held firmly by the crane hook on one side of the equipment.
[003] While lifting of the load, it is necessary to restrict the lifting of the boom beyond its minimum over hang limit position to avoid structural damages to the boom as well as the equipment.
[004] Reference may be made to the following:
[005] IN Publication No. 202141006851 relates to a system and method of counter weight linkage mechanism for operating of the pipelayer machine. The counter weight linkage mechanism comprises a counter weight bracket, a counter weight arm, a counter weight link, a counter weight frame, one or more counter weight blocks and one or more pins.
[006] The present invention claimed by us relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages by cutting off pilot oil supply to the winch which is being used for hoisting the boom in pipe layers.
[007] Publication No. US8783477 predetermined, relatively short distance. However, in use the boom often needs to extend further away from the undercarriage, and in so doing the lifting capacity of the pipelayer decreases.
[008] The present invention relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[009] Publication No. US2010102016 relates to a pipelayer and a method for of loading a pipelayer or excavator for transportation. One embodiment includes a method for transporting a pipelayer or excavator from a first work site to a second worksite via a public road.
[010] The present invention claimed by us relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[011] Publication No. US2019357422 relates to a pipe layer attachment for an excavator includes a winch configured to wind and unwind a cable having a hook attached thereto. The pipe layer attachment also includes a pipe layer boom configured to mount onto a boom of the excavator as a cantilever with the pipe layer boom extending beyond an end of the boom. The pipe layer boom is configured to be connected to an arm attachment pin connection of the boom and an arm cylinder pin connection of the boom.
[012] The present invention relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[013] Publication No. KR20140139256 relates to a pipe layer where a boom length can be adjusted comprises: a lower driving body; an upper frame mounted in the lower driving body in order to rotate where an operating room cap and an engine room are mounted; a boom adapter mounted in the front side of the upper frame; a boom whose bottom is fixated to the boom adapter in order to rotate, and to which is rotated by a boom cylinder whose bottom is fixated to the upper frame in order to rotate; a flag block detachably fixated to a first mounting member of a first center plate installed in the top of the boom, and supports a wire rope in order to elevate a hook; a winch which elevates the hook by the wire rope wound on a winch roller in accordance to the rotating direction of a winch motor mounted in the upper frame; and a boom expansion structure which includes a connecting plate detachably fixated to the top of the boom, a left and a right side frames mounted in the connecting plate in order to face each other, a second center plate fixated to a fixed position on the facing surfaces of the left and a right side frames, and a second mounting member installed in the second center plate where the flag block separated from the first mounting member is detachably fixated which adjusts the length of the boom by being separately connected with the top of the boom.
[014] The present relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[015] Publication No. US10850952 relates to a pipelayer machine having a counterweight assembly. The pipelayer machine can include a main body having first and second sides, a first side track provided on the first side of the main body and a second side track provided on the second side of the main body. A side boom can be provided on the first side of the main body.
[016] The present invention claimed by us relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[017] Publication No. CA2974274 relates to a pipelayer machine and more particular to the placement of inches on pipelayer machines.
[018] The present invention relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[019] Publication No. US2022213982 relates to an apparatus and method for laying pipe in a ditch. The apparatus comprises a mobile platform having a longitudinal central axis. A support extends from the mobile platform and includes a cradle. The present invention relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[020] IN Publication No. 302/CHE/2006 relates to specially designed counter weight linkage mechanism of a pipe layer ensures maximum stability while rising/lowering heavy loads on an uneven terrain at different boom overhang positions. Unique design & arrangement of linkages of the mechanism ensure maximum safety, ease of assembly and disassembly. The efficient hydraulic system ensures smooth, fine & precise control of the counter weight mechanism. The sturdy structures of the machine are designed to withstand severe shocks/ impact loads experienced during the working of the machine.
[021] The present invention relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[022] Publication No. US5332110 relates to a tractor having a pair of endless, segmented, high drive tracks include a side boom and a side-mounted counterweight. Boom angle is controlled by a boom winch with a load winch provided for lifting a load. Both winches are hydraulically driven and provide positive drive in raising and lowering. A boom automatic stop arrangement detects full-up boom position and actuates a release valve for dumping hydraulic pressure and preventing further retraction of the boom.
[023] The present invention claimed by us relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[024] Publication No. WO2017099277 relates to a device for protecting a pipe layer boom and, more specifically, to a device for protecting a pipe layer boom, capable of being variably mounted according to the size or the position of the boom.
[025] The present invention relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[026] Publication No. KR20100091440 relates to a pipe layer having a roll over protective structure to prevent injury of a driver in the event of a roll over by distributing impact and load transmitted to an engineer's cabin. A pipe layer comprises a lower travel body, an upper frame, a boom, a lifting unit, a boom adapter, and a roll over protective structure. The lower travel body is made up of a lower frame and tracks mounted on the right and left sides of the lower frame. The upper frame is installed to swivel on the lower travel body and equipped with an engineer's cabin and an engine room.
[027] The present invention creates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[028] Publication No. US3848751 relates to a mobile article handling vehicle adapted for off-the-road operations such as pipe laying in the most rugged types of terrain includes a light weight vehicle unit with ground engaging tires of great ground bearing area, a rotatable, upright mast on the unit, a tiltable boom with its inner end pivoted to the upper end of the mast, a hoist structure movable longitudinally along the boom between selected stations, and a supporting leg pivoted to the outer end of the boom and rotatable between a supporting position where the lower end thereof engages the ground to provide vertical support, and a traveling position substantially parallel to and above the boom.
[029] The present invention relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[030] Publication No. RU2629998 relates to machine engineering. During the control, the operation of the assembled pipe string capturing is performed, vertically move the pipes by means of the rope pulley block, horizontally move the pipeline by derricking. The derricking operation is performed with the help of the power hydraulic cylinder in combination with the guide slot and the tie rod, connecting the guide slot hinge with the boom top hinge. Crane efficiency increase.
[031] The present invention relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position using kickout valve, damper mechanism and linkages.
[032] Publication No. US2376019A relates to improvement in power releasing devices, and has particular reference to a device for releasing the power as applied to a crane boom. The principal object of this invention is to provide means for automatically stopping a crane boom at a predetermined point on its upward travel by using compressed air and clutch mechanism.
[033] Publication No. US2529193A relates to stop apparatus and more particularly to safety boom stops for rotary cranes and the like. An object of the invention is to provide and improved safety boom stop by using electrically operated limit switches.
[034] Publication No. US2840244A relates to improvements in boom stop ram operators. The principal object of this invention is to provide means for controlling and stopping of the upward movement of the boom by using vacuum or pull wire mechanism.
[035] When pipe layer is in operation, it often occurs that due to negligence of operator or over winding of hydraulic winch or existing kick out mechanism failure, which results in winch hoisting mechanism continues to exert a pull on the boom, when the boom is raised beyond a specified limit, the boom structure tends to bend inwards which may lead to distorter or failure of the boom structure and collateral damage as well.
[036] In order to overcome above listed prior art, the present invention aims to provide a mechanism which prevents boom from rising beyond specified position using spring loaded damper assembly linkage in kick out mechanism. The present invention relates to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position by using damper assembly with linkage mechanism and cut-off valve.
OBJECTS OF THE INVENTION:
[037] The principal object of the present invention is to provide an improved boom safety mechanism for operation of pipe layer.
[038] Another object of the present invention is to restrict the raising of pivoted boom beyond the specified position for safety reasons in the operation of pipe layer.
[039] Still another object of the present invention is to provide an improved boom safety mechanism and its method of operation which is simple and inexpensive construction and to be readily applicable on existing machine.
[040] Yet another object of the present invention is to provide damper assembly linkage introduced in-between kick out chamber and kick out valve in place of link rod.
[041] Still another object of the present invention is to provide damper assembly linkage, which accommodates any excessive (6.5 mm to 45 mm) linear movement, and also cut off the hydraulic pilot oil flow to winch mechanism using kick out valve and ensuring boom safety.
SUMMARY OF THE INVENTION:
[042] The present invention relates to an improved boom safety mechanism which is of simple and inexpensive construction and to be readily applicable to existing machine. To avoid the boom failure, 6.5 mm linkage movement is adequate to cut off oil flow using the kick out valve., But kick out chamber plunger rod may deliver 0 to 45 mm linear movement due to boom impulse, If excessive linear movement above 6.5mm is transferred to link rod, link rod may fail which in turn leads to boom failure. The present invention provides a damper assembly mechanism for accommodating excessive linear movement i.e., more than 6.5mm to 45mm and ensuring pilot oil cutoff to winch mechanism using the kick out valve and ensure boom safety.
BREIF DESCRIPTION OF THE INVENTION
[043] 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.
[044] Figure 1 shows an improved boom safety mechanism according to the present invention;
[045] Figure 2 shows the existing kick out mechanism;
[046] Figure 3 shows complete damper assembly;
[047] Figure 4 shows flowchart according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION:
[048] The present invention provides an improved boom safety mechanism which is of simple and inexpensive construction and to be readily applicable to existing machine. To avoid the boom failure, 6.5 mm linkage movement is adequate to cut off oil flow using the kick out valve., But kick out chamber plunger rod may deliver 0 to 45 mm linear movement due to boom impulse., If excessive linear movement above 6.5mm is transferred to link rod, link rod may fail which in turn leads to boom failure. The present invention provides a damper assembly mechanism for accommodating excessive linear movement i.e., more than 6.5mm to 45mm and ensuring pilot oil cutoff to winch mechanism using the kick out valve and ensure boom safety.
[049] In FIG-1, kick out chamber plunger rod (1) is connected with damper assembly (2) which is connected to the kick out valve (4) through support assembly (3). The kick out valve (4) is hydraulically connected to boom winch operation.
[050] In the above construction, when boom Winch hoisting mechanism is in operation, it continues to exert a pull on the boom, when boom crosses beyond a specified position, then boom pushes the kick out chamber plunger rod (1) of the kick out chamber. Plunger rod (1) moves the damper assembly (2) which absorbs the force exerted by plunger and limits the movement of the damper rod to 6.5 mm which is sufficient to cut off hydraulic pilot oil supply to boom winch mechanism, thus instantly stopping further upward movement of the boom.
[051] As the operator starts operating the boom joystick in opposite direction, boom start to move away from the kick out chamber, the kickout valve restores to its original position and winch mechanism will be coming to normal working condition.
[052] Applying this simple mechanism to pipe layer or ordinary crane, it is possible to prevent damage to the movable structural members, thus eliminating expensive repairs, eliminate the down time of the machine and human injury.
[053] In the existing kick out mechanism shown in Fig-2, If the boom is moved beyond the specified position, boom will push the kick out chamber plunger rod (1), then the kick out chamber plunger rod (1) will push the link rod (2), as a result the link rod will pull the kick out valve (4) and cut off the oil flow for operation of winch mechanism through the support assembly (3). Thereby Boom stops instantly. After few hours of operation, linkage lever (2) starts distorting and force to bend due to excessive linear movement of plunger rod (1) from kick out chamber (Fig-2). This leads to improper actuation of Kick out valve (4) due to which boom continues to move backwards which leads to distortion or structural damage of the boom and endangering the life of the operator.
[054] The complete damper assembly is shown in fig 3 The damper assembly consists of tube assembly; plunger assembly (2); spring (3); washer (4); bolt (5) and nut (6). The flowchart is given in figure 4.
[055] Thus, the safety mechanism comprising of the damper assembly linkage is installed. During boom hoisting operation, when boom reaches specified position, safety mechanism will pull the kick out valve spool which in turn cut off the oil supply to pilot line of winch control valve thereby stopping oil supply from control valve to winch motor due to which boom winch rotation is stopped and hence further movement of boom is stopped. This will prevent possible structural damage of the boom due to over winding of winch and costly repairs as well as loss of the use of the pipe layer during the repair period.
[056] Thus, the present invention provides to safe operation of Boom mechanism by restricting the boom movement beyond the predetermined position by using damper assembly with linkage mechanism and cut-off valve. The damper assembly prevents the damage of Boom structure/eventual causalities, by preventing the direct transfer of boom impulse on linkage during the actuation of cut-off valve. It also ensures the repeatability of performance of boom safety trigger / kick-out mechanisms with increased reliability.
[057] 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. An improved boom safety mechanism comprises kick out chamber plunger rod (1) connected with damper assembly (2) which is connected to the kick out valve (4) through support assembly (3) and kick out valve (4) is hydraulically connected to boom winch operation wherein when boom winch hoisting mechanism is in operation, it continues to exert a pull on the boom, when boom crosses beyond a specified position, then boom pushes the kick out chamber plunger rod (1) of the kick out chamber, the plunger rod (1) moves the damper assembly (2) which absorbs the force exerted by plunger and limits the movement of the damper rod to 6.5 mm to cut off hydraulic pilot oil supply to boom winch mechanism, thus instantly stopping further upward movement of the boom.
2. The improved boom safety mechanism, as claimed in claim 1, wherein a damper assembly mechanism for accommodating excessive linear movement is more than 6.5mm to 45mm and ensures pilot oil cutoff to winch mechanism using the kick out valve and ensure boom safety.
3. The improved boom safety mechanism, as claimed in claim 1, wherein as the operator starts operating the boom joystick in opposite direction, boom start to move away from the kick out chamber, the kickout valve restores to its original position and winch mechanism will be coming to normal working condition.
4. The improved boom safety mechanism, as claimed in claim 1, wherein during boom hoisting operation, when boom reaches specified position, safety mechanism will pull the kick out valve spool which in turn cut off the oil supply to pilot line of winch control valve thereby stopping oil supply from control valve to winch motor due to which boom winch rotation is stopped and hence further movement of boom is stopped.