WO2008111097A2

WO2008111097A2 - Wire holder brush for window regulator

Info

Publication number: WO2008111097A2
Application number: PCT/IN2008/000149
Authority: WO
Inventors: Bijon Nag; Chandrashekhar Vaidyanathan; Srinivasan Duraisamy; Chelladurai Periasamy
Original assignee: Ifb Automotive Private Ltd
Priority date: 2007-03-14
Filing date: 2008-03-14
Publication date: 2008-09-18
Also published as: WO2008111097A3

Abstract

The subjet matter provides a wire holder bush of a window regulator assembly which is operable in the automobiles to facilitate the up-down movement of a window glass. The proper movement of the window glass, sometimes, is not achieved due to the slackness created in a wire rope passing through a wire holder bush. A stipulated quantity of tension is desirable in the wire rope to avoid the slackness. A window regulator assembly for a slidable window glass has a guide rail, which is mounted vertically on a door panel. A lifting plate is disposed on the guide rail. The window regulator assembly includes a base plate with a plurality of slots, which accommodate a plurality of wire holder bushes. The wire holder bush is provided with a head and a tapered body. Each of the wire rope sub-assemblies are passed through each of the wire holder bushes

Description

WIRE HOLDER BUSH FOR WINDOW REGULATOR TECHNICAL FIELD

The subject matter described herein in general relates to a window regulator assembly of a vehicle and in particular relates to a wire holder bush for tensioning the wire rope in a window regulator assembly. BACKGROUND

Automotives usually employ window regulators, operable either manually or electronically, to facilitate the up-down movement of a window glass mounted on a door panel of an automobile. Typically, in a wire driven window regulator, a wire rope is wound around a drum pulley. The wire rope guides the up and down movement of the window glass during the lifting and lowering of window glass. Moreover, the wire rope is passed through the wire holder bush. The wire holder bush is included therein for maintaining the tension in the wire rope.

The tensioning of the wire rope avoids slackness which may otherwise affect the performance of the window regulator. The slackened wire rope causes increased stress on the wire rope and other parts of the system resulting in uneven motion of the wire during the up-down movement of the window glass. Further, undesired noise is produced due to the collision of inner and outer wire holder parts. Therefore, . a stipulated quantity of tension is required in the wire rope for the proper movement of the window glass.

Conventionally, a wire holder bush is fitted with a washer to ensure firm contact between the bush and the base plate. The washer, employed between the bush and the base plate, maintains the desired tension in the wire rope and therefore, is an essential component of the regulator assembly. Even though usage of washer herein is prevalent, the prolonged usage of the washer causes various problems such as slipping of wire rope subassembly from the wire holder bush, frequent changing of wire rope length, wearing of the wire rope, less durability, etc. Furthermore, washer acts as an additional component to be attached in the window regulator system.

There is, therefore, a need for providing a well designed wire holder bush that overcomes the above said problems and also replaces the usage of washers in window regulator assembly. SUMMARY

The subject matter described herein is directed to a wire holder bush which creates and maintains the desired tension in the wire rope subassembly. The use of the wire holder bush described herein eliminates the use of additional components for the purpose.

In accordance with one embodiment of present subject matter, a window regulator assembly for a slidable window glass comprises a guide rail, a lifting plate, wire rope subassembly and a base plate. The guide rail, having an upper end and a lower end, is mounted vertically on a door panel. The lifting plate, which carries the window glass, is disposed on the guide rail and is made to slide thereon. The base plate further includes a plurality of slots, a plurality of wire holder bushes, a drum, and a plurality of wire rope subassembly. Each wire holder bush is accommodated in each of the slot and each of the wire ropes of the wire rope subassemblies passes through each of the wire holder bush. The wire holder bush provided herein maintains the desired tension in the wire ropes thereby providing the proper movement of the window glass.

The wire holder bush of the present subject matter comprises a head and a tapered body. The head herein has a first side and a second side including a plurality of projections. The second side abuts the tapered body of the wire holder bush. Further, the wire ropes having a first end and a second end are passed through each of the wire holder bushes. The first end of each of the wire ropes are wound on the drum and the second end of each of the wire ropes are rigidly attached to the lifting plate. The lifting plate slides over the guide rail as guided by plurality of wire ropes included in the base plate. The wire holder bush, as aforesaid, achieves a design which reduces the number of components to be used in the window regulator assembly. Due to the projections fabricated on the wire holder bush, desired tension is created and maintained in the wire ropes. Further, the slackness of the wire ropes is avoided to allow proper movement of the window glass. Further, eliminating the slackness of the wire rope provides a solution to various problems such as slipping of wire rope from the wire holder bush, frequent changing of wire rope length, wearing of the wire rope, less durability, and so on. The undesired noise produced due to the collision of inner and outer wire holder parts is removed.

These and other features, aspects, and advantages of the present subject matter will become better understood with reference to the following description and appended claims. This summary is provided to introduce a selection of concepts in a simplified form. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

BRIEF DESCRIPTION OF DRAWINGS The above and other features, aspects, and advantages of the subject matter will become better understood with regard to the following description, appended claims, and accompanying drawings where:

Fig.l illustrates a perspective view of a window regulator which is mounted inside a door panel of a door.

Fig.2 (a) & Fig.2 (b) illustrates a perspective view of a window regulator assembly.

Fig.3 illustrates a perspective view of a base plate subassembly of window regulator assembly of Fig.2 (a) & Fig.2 (b). Fig.4 illustrates a perspective three dimensional top view of the wire holder bush of window regulator assembly of Fig.2 (a) & Fig.2 (b).

Fig.5 illustrates a three dimensional view of the wire holder bush with the base plate subassembly of Fig.3 in a neutral state.

Fig.6 illustrates a three dimensional view of the wire holder bush with the base plate subassembly of Fig.3 in a locked state.

Fig.7 illustrates a perspective view of different thickness wire holder bushes assembled in a base plate subassembly of Fig.3.

Fig.8 (a) illustrates a front view of the wire holder bush of window regulator assembly of Fig.2 (a) & Fig.2 (b). Fig.8 (b) illustrates a top view of the wire holder bush of window regulator assembly of Fig.2 (a) & Fig.2 (b).

Fig.8 (c) illustrates a side view of the wire holder bush of window regulator assembly of Fig.2 (a) & Fig.2 (b). DETAILED DESCRIPTION The present subject matter is related to a wire holder bush of a window regulator assembly for a slidable window glass. The window regulator assembly for a slidable window glass comprises a guide rail, a lifting plate, wire rope subassembly and a base plate. The guide rail, having an upper end and a lower end, is vertically mounted on a door panel. A first roller pulley is attached to the upper end and a second roller pulley is attached to the lower end. The lifting plate, which carries the window glass, is disposed on the guide rail such that the lifting plate can slide over the guide rail.

The base plate of the window regulator assembly includes a plurality of slots, a plurality of wire holder bushes, a drum, and a plurality of wire rope sub-assemblies. Each wire holder bush is accommodated in each of the slot and each wire rope of the wire rope subassembly, having a first end and a second end, is passed through each of the wire holder bushes. The first end of each of the wire rope subassemblies are wound on the drum and the second end of each of the wire rope sub-assemblies are rigidly attached to the lifting plate. During the up-down movement of the window glass, one of the wire rope subassemblies unwound from the drum and another wire rope subassembly is wound thereon. The wire rope subassembly, which is further attached to the lifting plate, slides the lifting plate over the guide rail in the direction of the wire rope subassembly which winds.

The wire holder bush made up of plastic material such as delrin lOOp is comprised of a head, a tapered body and a hollow passage between the head and the tapered body. The head herein has a first side and a second side. The second side of the head includes a plurality of projections and abuts the tapered body of the wire holder bush. The projections fabricated are substantially symmetrical. The thickness of the projections fabricated is preferably about 2mm to 4mm. During the rotation of wire holder bush, preferably in a clockwise direction, wire holder bush is projected outward a distance of about 2mm to 4mm from the slot, the distance being equivalent to the thickness of the projection. Further, the base plate is provided with a depression on the sides of the slots to accommodate the projections therein, which are projected outward during the rotation of the wire holder bush or preferably during a locked state of the wire holder bush. In the locked state of the wire holder bush one of the projections fit into the slots. The wire holder bush is made adjustable due to the projections on the periphery of the dorsal side of the wire holder bush. Due to the locked state of the wire holder bush, the wire rope subassembly expands thereby creating and maintaining the desired tension in the wire rope subassembly. Although the subject matter has been described in considerable detail with reference to certain preferred embodiments thereof, other embodiments are possible. As such, the spirit and scope of the appended claims should not be limited to the description of the preferred embodiment contained therein.

In accordance with one embodiment of the present subject matter, Fig.l illustrates a window regulator assembly 100 which is mounted inside a door panel of a door 102 of an automobile. The window regulator assembly 100 holds a window glass 104 to raise or lower the window glass 104 by the operation of the window regulator assembly 100.

Fig.2 (a) & Fig.2 (b) illustrate a perspective view of the window regulator assembly 100 with respect to one embodiment of the present subject matter.

The window regulator assembly 100 of the present invention comprises a guide rail 105. The guide rail 105 is vertically mounted inside the door with some inclination with respect to horizontal and is fastened to the vehicle-door by means of mounting brackets 110. The guide rail 105 has an upper end and a lower end. Further, as shown in Fig.2 (b), a pair of roller brackets 115 and 120 is welded to the upper end and lower end of the guide rail 105 respectively in order to dispose a pair of roller pulleys 125 and 130 respectively thereon.

The window regulator assembly 100 further comprises a lifting plate 135, disposed on the guide rail 105, and a base plate 140. The base plate 140 includes two wire rope subassemblies 141 and 143, each having a first end and a second end. The wire rope subassemblies 141 and 143 further comprises a wire rope 142 each. The wire rope subassemblies 141 and 143 are further provided with metallic conduits 145 and 150 respectively, through which the wire rope 142 passes through. The wire rope 142 is made of a flexible and tensile material, preferably steel and metallic alloys. Further, the wire rope sub-assemblies 141 and 143 are provided with the crimps at the two ends in order to fix the wire rope 142. The first end of each of the wire ropes 142 are wound on a drum 155 and the corresponding second ends are rigidly attached to the lifting plate 135. Subsequently, the wire ropes 142 of the wire rope subassemblies 141 and 143 pass over the roller pulleys 125 and 130. The wire ropes of the wire rope subassemblies 141 and 143 are wound on the drum 155 such that, during the rotation of the handle or an electric motor of the vehicle for the up-down movement of the window glass 104, one of the wire ropes of the wire rope subassemblies 141 and 143 will unwind and simultaneously, the other will wind around the drum 155. Moreover, winding of one of the wire rope 142 will cause the lifting plate 135 to slide in the corresponding direction. The lifting plate 135 is therefore made to slide on the guide rail 105 by the winding and unwinding of the wire ropes of the wire rope subassemblies 141 and 143. A drum housing 160 further encloses the 'drum 155 to hold the wire ropes of the wire rope subassemblies 141 and 143 wound thereon the drum 155.

An anti-rattle sleeve 165 and 170 made up of materials such as rubber is wrapped around each of the conduits of the wire rope subassemblies 141 and 143 respectively to avoid contact between the window glass 104 and the wire rope subassemblies 141 and 143.

Fig. 3 elaborates the base plate 140 of the window regulator assembly 100. The base plate 140 comprises slots 205 and 210 located at the end of the base plate 140. The slots 205 and 210 accommodate wire holder bush 215 and 220 respectively. On both of the sides of each of the slots 205 and 210 depressions are provided in order to hold the wire holder bush 215 and 220 in the locked state. The wire rope subassemblies 141 and 143 pass through the wire holder bush 215 and 220 respectively. The rotation of the wire holder bush 215 and 220 lock the wire holder bush 215 and 220 thereby maintaining the desired tension in the respective wire ropes 142.

Fig. 4 illustrates a perspective top view of the wire holder bush 215 in the inverted position. The wire holder bush 215 includes a head 305, a tapered body 310, and a hollow passage 315 along the longitudinal axis of the wire holder bush 215. The head 305 has a first side and a second side. The second side further comprises two projections 320 and 325 on the periphery of the dorsal side. One side of the projections 320 and 325 is a tapered surface which provides easy sliding during the rotation of the wire holder bush 215. The other side of projections 320 and 325 is a flat surface which enables the wire holder bush 215 to rest on the base plate 140 during the locked state. This arrangement maintains tension in the wire rope and reduces the wire rope slackness. The projections 320 and 325 preferably have a thickness of about 2 mm to 4mm.

Fig.5 & Fig.6 show a three dimensional view for the wire holder bush 215 accommodated in the slot 205. The wire holder bush 215 illustrated in Fig.5, is in its neutral position, i.e. desirable tension of the wire rope 142 is not achieved in this position. The distance between the end of the base plate 140 and the first side of the head 305 is about 10mm.

A clockwise rotation of 90^° of wire holder bush 215 is made to obtain the locked state of the wire holder bush 215 as shown in Fig.6. During the rotation of the wire holder bush 215, the tapered surface on the side of the projections 320 and 325 enable sliding of the wire holder bush 215. The depressions provided on the side of the slots 205 hold the projections 320 and 325 during the locked state. Further the flat surface on the side of the projections 320 and 325 provide enable resting of the wire holder bush 215 on the base plate 140. Thus, the locked state of the wire holder bush 215 causes the desired tension in the wire rope sub-assembly 141. The distance between the end of the base plate 140 and the first side of the head 305 during the locked state is about 12mm.

The fabricated projections 320 of wire holder bush 215 (shown in Fig. 4), usually have a thickness of about 2 mm to 4 mm on the periphery of dorsal side of the wire holder bush 215. This ensures maintaining required tension in the wire rope of the wire rope subassembly 141 and a firm contact between the wire holder bush 215 and the base plate 140. The appropriately sized projections 320 and 325 of the wire holder bush 215 replace the usage of an additional component such as a washer in the wire rope 142.

In yet another embodiment of the present subject matter, the wire holder bush 215 has a differential thickness X^_t of approximately 2 mm on one side of the base plate 140 and a differential thickness Y_dt of approximately 4 mm on the other side of the base plate 140. This enables the wire rope sub-assembly 141 to achieve a desired overall tension as either a combination or difference of thickness of wire holder bush 215 on both sides of the base plate 140. Fig.7 shows the two different thickness wire holder bushes assembled with the base plate 140. Fig.8 (a) illustrates the front view of the wire holder bush 215 of the window regulator assembly of Fig.2 (a) & Fig.2 (b). The front view of the wire holder bush 215 shows the head 305 and the tapered body 310 of wire holder bush 215. The tapered body 310 is provided to the wire holder bush 215 to ease the insertion process. The hollow passage 315 accommodates wire rope 142.

Fig.8 (b) illustrates the top view of the wire holder bush 215 wherein the head of wire holder bush 215 is shown. The head of wire holder bush 215 is designed in such a way so as to achieve rotation of the wire holder bush 215, wherein the end accommodating projections of wire holder bush 215 is made arc like. The hollow passage 315 is accommodated in the wire holder bush 215.

Fig.8 (c) illustrates the side view of the wire holder bush 215 wherein the projections 320 and 325 of the wire holder bush 215 are shown. The projections are held by the depressions on the sides of the slot 205 in the locked state. The side view of the wire holder bush 215 also shows the thickness of projections 320 and 325. The projections 320 and 325 are in firm contact with the base plate 140 when the wire rope sub assembly 141 is strained, thereby increasing the overall tension in the assembly and reducing the slackness of the wire rope 142.

The aforementioned versions of the subject matter and equivalent thereof have many advantages, including those which are described below. One advantage of the present subject matter is that the wire holder bush with the projections on the periphery avoids the usage of additional component such as washer. Further, usage of the wire holder bush avoids any inadvertent error which may have occurred during assembling of washer in between the base plate and the wire holder bush. The wire holder bush is, therefore, user friendly and has enhanced field serviceability. Furthermore, desired tension is created and maintained in the wire. The slackness of the wire rope is avoided which otherwise disturbs proper movement of the window glass. Various problems caused due to the slackness of the wire rope such as slipping of wire rope from the wire holder bush, frequent changing of wire rope length, wearing of the wire rope, less durability, etc are solved. In addition, any undesired noise produced due to the collision of inner and outer wire holder parts is removed.

Although the subject matter has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the subject matter, will become apparent to persons skilled in the art upon reference to the description of the subject matter. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the present subject matter as defined.

Claims

I/We claim:

1. A window regulator assembly for a slidable window glass, said window regulator comprising: a guide rail mounted vertically on a door panel, said guide rail having an upper end and a lower end; a lifting plate disposed on said guide rail; and a base plate comprising a plurality of slots on said base plate, a plurality of wire holder bushes accommodated in each of said slot, wherein each of said wire holder bush comprises a head and a tapered body, wherein said head comprises a first side and a second side, and wherein said second side of said head comprises a plurality of projections and said second side of said head abuts said tapered body of said wire holder bush; a drum, and a plurality of wire rope sub-assemblies, wherein each said wire rope sub- assembly has a first end and a second end, wherein said first ends of each of said wire rope sub-assembly are wound on said drum and said second ends of each of said wire rope sub-assembly are attached to said lifting plate, and wherein each of said wire rope sub-assemblies are passed through each of said wire holder bushes.

2. The window regulator assembly as claimed in claim 1, wherein a first roller pulley is attached to said upper end and a second roller pulley is attached to said lower end.

3. The window regulator assembly as claimed in claim 1, wherein said wire holder bush comprises a hollow passage along the longitudinal axis of said wire holder bush.

4. The window regulator assembly as claimed in claim 1, wherein said wire holder bush is rotatable in said slot provided on said base plate.

5. The window regulator assembly as claimed in claim 1, wherein the thickness of said projections on the periphery of the dorsal side of said wire holder bush is about 2mm to 4mm.

6. The window regulator assembly as claimed in claim 1, wherein said projections on the periphery of the dorsal side of said wire holder bush are symmetrical.

7. The window regulator assembly as claimed in claim 1, wherein said wire holder bush is rotated at an angle, about 90° in clockwise direction.

8. The window regulator assembly as claimed in claim 1, wherein rotation of said wire holder bush in clockwise direction projects said wire holder bush outward from said slots.

9. The window regulator assembly as claimed in claim 1, wherein said base plate is provided with a depression on the sides of said slots.

10. The window regulator assembly as claimed in claim 1, wherein said projections lock said wire holder bush in said depression, due to rotation of said wire holder bush.