Title of Invention

HYDRAULIC DOOR CLOSER

Abstract

A Hydraulic Door Closer comprising an oil operated hydraulic cylinder, wherein a spring loaded piston is reciprocating having a closing nut guiding the piston rod which is operated by a rack and pinion mechanism; an arm assembly connecting the door frame with the door closer unit, the said door closer unit is fitted on the door by screwing means, when the door is opened the lever operates the pinion and the rack mechanism, thereby pulling out the piston by compressing the spring and while closing the door the spring releases the energy and closes the door.

Full Text

FORM 2 THE PATENTS ACT, 1970 (39 of 1970) COMPLETE SPECIFICATION (See Section 10) HYDRAULIC DOOR CLOSER GODREJ & BOYCE MFG. CO. LTD. of LOCKS DIVISION PLANT-18 PIROJSHANAGAR, VIKHROLI, MUMBAI - 4 00 0 79, MAHARASHTRA, India, INDIAN Company hereby declare : - GRANTED 23-9-2003 The following specification particularly describes the nature of the invention and the manner in which it is to be performed : - ORIGINAL HYDRAULIC DOOR CLOSER This invention relates to a hydraulically regulated door closer for doors opening to one side only. A hydraulic door closer is an equipment for closing of doors by controlled release of energy stored in compression springs. This is suitable for both left hand opening and right hand opening doors without any change in the constituent parts. Closing time of the door can be adjusted with the help of one or two screws where short adjustment screw controls the speed throughout the closing cycle and long adjustment screw controls the speed during last 15 - 20° closing of the door. Conventional door closers have integrated assembly of rack and pinion housed in the body with oil and there are ends of the pinion which have rotating shafts closed with " O " rings which are susceptible to wear , leading to leakage of oil and resulting in reduced performance. Also assembly / servicing is cumbersome and requires specialized skills and equipment. In the present invention , the hydraulic and mechanical movements have been physically seperated thereby reducing potential areas of wear / tear and leakage of oil. Construction being modular is easy to assemble and service. Innovative covers to suit door decor is also possible. Additionally by varying the use of one / two springs inside the piston, the application can be modified for light / heavy doors. Conventional door closers have adjustment screw to regulate the speed of opening / closing which is located on the side, facing the hinge where practically lot of difficulty is experienced to operate with the use of a screwdriver, whereas in the present invention, speed adjusting screw is on the side, facing the open end of the door. This facilitates easy accessing and regulating the door for required door closing speed. Main objective of this invention is to provide a durable and reliable leak proof gadget for controlling easy opening of doors and smooth closing without jerk or bang. The another object of the invention is to split the element into the hydraulic cylinder and pinion mechanism and thereby oil leakage points are minimised. Still further object is to provide Hydraulic Door Closer wherein, the piston rod is reciprocating in the cylinder which thereby eliminating the rotary movement and transfers it in " TO AND FRO MOTION " ; thereby rotary oil seal points are replaced by sliding oil seal joint. In the present invention there is only one oil seal joint, still another object of the invention is to provide the setting screws at the side away from the door hinges, thereby easy manipulation and also easy adjustment of door closing speed and also door closer unit which is placed on the front side of the door instead of the rear side. Another object of this invention is ease in assembly and servicing . Further object and advantages of this invention will become apparent from the following description and the accompanying drawings which illustrates certain preferred embodiment, wherein : Figure 1 : is a rear perspective view of the present invention. Figure 2 : is an exploded view of the present invention. Figure 3 : is a sectional view taken across the length of the gadget . Referring to the Figures 1 , 2 and 3 , there is shown the door closer of present invention which in broad aspects comprises of a arm assembly (A) and door closer unit (C). A Hydraulic Door Closer (C) which is fitted on the door (D) by screw means , the said hydraulic closer is connected with the two levers , one of the levers is connected with the pinion of hydraulic door closer and other lever (9) is connected to door frame . The hydraulic door closer operated on the principle of cylinder and piston movement through a rack & a pinion . A compressed spring is housed in the cylinder and screwed by means of end cap and oil seals. The piston rod is movable by means of Rack and pinion mechanism , due to the opening of the door the cylinder rod will be pulled out thereby compressing the spring inside the cylinder and when the door is closed the spring will relax and release energy to close the door. The speed of closing and opening can be varied by using different types of spring , or by adjusting the screw provided. The screw is provided near the door openend side, therefore it is clearly visible and easy for operation. Door closer unit (C) is mounted on door (D) an arm assembly (A) is mounted on doorframe (B) which is assembled to door closer unit (C). In figure 2, there is shown the exploded view of door closer unit (C) . It comprises of the parts as shown in the diagram wherein piston assembly (PA) consist of end cap (110) in which oil seal (118) is push fitted and " O " Ring (116) for end cap (110) and " O " ring (116) for retainer is fitted over it along with the retainer (125) , Compression springs inner (15) and outer (16) are fitted on piston rod (122) Above this Piston (121) is fitted a stainless steel ball of 5mm diameter (127) and a washer (128) is placed on piston (121) which is finally assembled by a M5 Nut (114) . The above assembly (PA) is assembled with a cylinder housing assembly (CHA) which comprises of cylinder housing (19) assembled with 4 stainless steel balls (126) closing four side holes of cylinder housing (19) and adjustment screws long (11) and short (12) are assembled with " O " ring (117) for closing two back speed regulating holes of cylinder housing (19). A rack housing assembly (RHA) is done with guide strip (111), a pinion (120) , push fitted with a collar bush (14) and bush for rack housing (13) and rack housing cover (18) fitted with 3 M3 screws (112). Assemblies of PA & CHA is then assembled with RHA using a pin for piston rod (119) . In the final assembly , PA + CHA + RHA + Cover are fitted using 4 M4 c'sk screws (113) and two cheese head screws. As many possible , embodiments may be made of the invention without departing from the scope thereof , it is to be understood that all matter herein set forth or shown in accompanying drawings is to be interpreted as illustrative and not in limiting sense. This is an embodiment of the invention and several modifications are possible which may be considered within the spirit and ambit of this invention. WE CLAIM: 1. A Hydraulic Door Closer comprising an oil operated hydraulic cylinder, wherein a spring loaded piston is reciprocating having a closing nut guiding the piston rod which is operated by a rack and pinion mechanism; an arm assembly connecting the door frame with the door closer unit, the said door closer unit is fitted on the door by screwing means, when the door is opened the lever operates the pinion and the rack mechanism, thereby pulling out the piston by compressing the spring and while closing the door the spring releases the energy and closes the door. 2. A Hydraulic Door Closer as claimed and substantially herein described. Dated this 6ith day of September, 2003.

Documents:

932-mum-2003-cancelled pages(23-09-2003).pdf

932-mum-2003-claims(granted)-(23-09-2003).doc

932-mum-2003-claims(granted)-(23-09-2003).pdf

932-mum-2003-correspondence(11-02-2005).pdf

932-mum-2003-correspondence(ipo)-(02-11-2004).pdf

932-mum-2003-drawing(23-09-2003).pdf

932-mum-2003-form 1(08-09-2003).pdf

932-mum-2003-form 19(15-07-2004).pdf

932-mum-2003-form 2(granted)-(23-09-2003).doc

932-mum-2003-form 2(granted)-(23-09-2003).pdf

932-mum-2003-form 3(07-08-2003).pdf

932-mum-2003-power of attorney(23-09-2003).pdf

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