FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
As amended by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2006
COMPLETE SPECIFICATION (See section 10 and rule 13)
TITLE OF THE INVENTION
Shoulder forming mechanism of a mount making machine for manufacture of fluorescent tube light
APPLICANTS
Crompton Greaves Limited, CG House, Dr Annie Besant Road, Worli, Mumbai - 400 030, Maharashtra, India, an Indian Company
INVENTORS
Nair Thankappan Gopalakrishnan Melathakathutte and Kuruppu Vasu Gangadharan Kallarikkal, both of Crompton Greaves Ltd, Light Source Division, Baroda, Gujarat, India, both Indian nationals
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to
be performed:

FIELD OF THE INVENTION
This invention relates to a shoulder forming mechanism of a mount making machine for the
manufacture of a fluorescent tube light.
BACKGROUND OF THE INVENTION
A fluorescent tube light comprises a glass tube coated with a fluorescent material at the inner side thereof and fitted with a pair of mounts, one at each end of the glass tube. Each of the mounts comprises a metal cap having a glass insulator body at the inner side thereof and a pair of cap pins projecting out from the outer side thereof through an insulator strip located at the center of the closed end of the cap. A pair of straight parallel conductor wires or leadwires are fixed in the glass insulator body and project out of the glass insulator body with their inner ends connected to the cap pins. In order to provide required electrical clearance between the conductor wires, the conductor wires are formed with shoulders, namely bents in the outward direction followed by bents in the forward direction. A filament is fixed between the outer ends of the conductor wires. The shoulders are formed in a shoulder forming mechanism of a mount making machine which forms a part of a fluorescent tube light assembling machinery. Besides the mount making machine, the fluorescent tube light assembling machinery also comprises a fluorescent coating machine, a baking machine, a sealing machine, an exhausting machine and a capping machine. The shoulder forming mechanism of the mount making machine comprises a pair of stationary jaws mounted on the machine bed in spaced apart relationship with each other. Each of the stationary jaws comprises an upright member. The shoulder forming mechanism also comprises a pair of movable clamping jaws mounted on the machine bed between the stationary

jaws. Each of the movable clamping jaws comprises an upright portion and a clamping head at the top thereof comprising an outwardly bent portion in the direction of the respective stationary jaw. The shoulder forming mechanism also comprises a movable wedging jaw mounted on the machine bed between the movable jaws offset with the movable jaws. The movable clamping jaws are disposed for back and forth movement with respect to a side of the stationary jaws and also movable back and forth with respect to the stationary jaws. The wedging jaw is disposed for movement into the space between the movable jaws and back. Drive to the movable clamping jaws and movable wedging jaw is given by a main shaft disposed for up and down movement and connected to the movable clamping jaws and movable wedging jaw through a cam and roller arrangement. Drive to the main shaft is given by a cam and lever mechanism.
The shoulder forming mechanism operates in a cyclic manner. In a cycle of operation of the shoulder forming mechanism, when the main shaft moves up, the movable clamping jaws move in from the side and align with the stationary jaws and then move forward and press against the stationary jaws when the outwardly bent portions of the clamping jaws slide against the top ends of the stationary jaws. The movable wedging jaw moves in and tightens against the movable jaws. When the main shaft moves down, the movable wedging jaw moves back to its original position. The movable clamping jaws slide back from the stationary jaws and then to the side and to their original position. The mount making machine also comprises a mount holder mounted on the machine bed in the proximity of the shoulder forming mechanism adapted to hold a mount and rotate about a vertical axis and also move up and down about the vertical axis. During operation of the shoulder forming mechanism, a mount with straight conductor wires is held in the mount holder and the mount holder is moved down and the conductor wires are

positioned between the stationary jaws. The shoulder forming mechanism is operated such that the movable clamping jaws move in from the side and align with the stationary jaws and then move forward and engage against the straight conductor wires and the respective stationary jaws to form outwardly and downwardly directed bents or shoulders in the conductor wires. The movable wedging jaw is moved forward to tighten against the movable clamping jaws. On completion of shoulder formation, the wedging jaw and clamping jaws are moved back to their original positions. The mount holder is moved up to disengage the mount from the shoulder forming mechanism.
The above shoulder forming mechanism comprises a large number of components and is expensive and is not reliable. Wear and tear to the shoulder forming mechanism is high as a result of the large number of components, especially the clamping heads of the movable clamping jaws as they frequently slide over and rub against the top ends of the stationary jaws. Due to frequent operation of the mechanism, the clamping jaws will become deformed and will not form the shoulders uniformly and the life of the shoulder forming mechanism will be reduced. The shoulder forming mechanism describes a large number of movements to complete the shoulder forming operation. As a result, the shoulder forming operation is time consuming and reduces productivity. The drive mechanism of the movable clamping jaws and movable wedging jaw is very complicated and increases both initial cost and maintenance cost of the shoulder forming mechanism.

OBJECTS OF THE INVENTION
An object of the invention is to provide a shoulder forming mechanism of a mount making machine for the manufacture of a fluorescent tube light, which mechanism comprises few components and is reliable, simple in construction and easy and convenient to operate and is economical.
Another object of the invention is to provide a shoulder forming mechanism of a mount making machine for the manufacture of a fluorescent tube light, which mechanism reduces the number of movements and reduces time for shoulder formation and increases productivity.
Another object of the invention is to provide a shoulder forming mechanism of a mount making machine for the manufacture of a fluorescent tube light, which mechanism ensures trouble free operation thereof for a long period of time and has reduced wear and tear and increased life and reduces maintenance and maintenance cost.
Another object of the invention is to provide a shoulder forming mechanism of a mount making machine for the manufacture of a fluorescent tube light, which mechanism is versatile.
DETAILED DESCRIPTION OF THE INVENTION
According to the invention there is provided a shoulder forming mechanism of a mount making machine for the manufacture of a fluorescent tube light, the mechanism comprising a horizontally disposed actuator mounted at the top of a main shaft vertically disposed for up and down movement about a vertical axis, the actuator being movable up and down with the main

shaft on a guide shaft vertically disposed in the proximity of the main shaft and mounted to the bed of the mount making machine, a horizontally disposed fixed jaw support mounted at the top of the guide shaft above and in spaced apart relationship with the actuator, a fixed jaw comprising a base mounted on the fixed jaw support and a flat upright portion projecting upwardly from the base having tapered faces at the opposite sides of the top end thereof and a pair of movable jaws, each comprising an angular member disposed at each side of the upright portion and pivoted to the fixed jaw support at the corner of the angular members with one limbs of the angular members resting against the actuator and the other limbs of the angular members disposed in the proximity of the upright portion and a clamping head at the top of the other limb of each of the angular members, the clamping head having an outwardly bent inner end with a tapered surface matching with the tapered face at each side of the top end of the upright portion and adapted to press against the tapered face at the respective side of the top end of the upright portion.
The following is a detailed description of the invention with reference to the accompanying drawings, in which:
Fig 1 is a partially exploded isometric view of the shoulder forming mechanism of a mount making machine for the manufacture of a fluorescent tube light;
Fig 2 is an elevation of the shoulder forming mechanism of Fig 1;
Fig 3 is an elevation of the fixed jaw of the mechanism of Fig 1; and

Figs 4 and 5 are elevations of the angular member and clamping head of a movable jaw of the mechanism of Fig 1, respectively.
The shoulder forming mechanism 1 of a mount making machine (not shown) for the manufacture of a fluorescent tube light (not shown) as illustrated in Figs 1 to 5 of the accompanying drawings comprises a horizontally disposed actuator 2. The actuator comprises a flat plate of stepped construction having a lower flat portion 3 and a raised flat portion 4 and a pair of lateral arms 4a, 4a each extending laterally from the bottom of each of the raised flat portions. Each of the lateral arms comprises an upstanding support member 4b with a tapered head 4c. The actuator plate is mounted at the top of a main shaft 5 vertically disposed for up and down movement about a vertical axis in a tubular main body 6 which is provided with a mounting flange 7 around it. The mounting flange is formed with mounting holes 8 and is fixed to the bed (not shown) of the mount making machine with bolts (not shown) tightened in the mounting holes 8 in the flange and corresponding mounting holes (not shown) in the bed of the mount making machine. The actuator plate is movable up and down with the main shaft on a guide shaft 9 vertically disposed in the proximity of the main shaft and mounted to the mounting flange. 10 is a horizontally disposed fixed jaw support comprising a T-shaped fiat member. The perpendicular portion 11 of the fixed jaw support is mounted at the top of the guide shaft through mounting hole 12 provided in the fixed jaw support. The fixed jaw support is disposed above and in spaced apart relationship with the actuator plate. 13 is a fixed jaw comprising a base 14 and a flat upright portion 15 projecting upwardly from the base. The fixed jaw is mounted on the fixed jaw support by tightening bolts (not shown) in the mounting holes 16 in the base of the fixed jaw and

corresponding mounting holes 17 in the fixed jaw support. The upright portion comprises tapered faces 18 at opposite sides of the top end thereof. The shoulder forming mechanism also comprises a pair of movable jaws each comprising an angular member 19 disposed at each side of the upright portion and pivoted to the lateral extensions 20 of the fixed jaw support at the corners of the angular members with pivot pins 21 engaged in holes 20a in the lateral extensions and 22 at the corners of the angular members. One limbs 23 of the angular members rest against the tapered heads 4c of the upstanding support members of the actuator and the other limbs 24 of the angular members are disposed in the proximity of the upright portion of the fixed jaw. The top end of the other limb of each of the angular members comprises a channel 25 and a mounting hole 26 at the center thereof. The movable jaws each also comprises a pair of clamping heads 27 each located in the channel at the top end of the other limb of each of the angular members. Each of the clamping heads comprises an outwardly bent inner end 28 with a tapered surface 29 matching with the tapered face at each side of the top end of the upright portion and adapted to close against the tapered faces at the opposite sides of the top end of the upright portion. Each of the clamping heads is provided with an oblong slot 30 along the length thereof. The clamping heads are mounted to the top ends of the respective other limbs of the angular members by tightening bolts (not shown) in the oblong slots in the clamping heads and mounting holes 26 at the top ends of the other limbs of the respective angular members against the clamping heads. The distance between the inner ends of the clamping heads and the upright portion of the fixed jaw can be adjusted by loosening the tightening bolts, sliding the clamping heads linearly in and out in the channels at the top ends of the other limbs of the angular members and retightening the tightening bolts. The distance by which the linear adjustment of the clamping heads can be carried out is restricted by the length of the oblong slots therein. By

adjusting the position of the clamping heads at the top of the other limbs of the movable jaws, the stroke of the movable jaws with respect to the upright portion of the fixed jaw can be adjusted. Preferably the angle of taper at the opposite sides of the top end of the upright portion and at the outwardly bent inner end of the clamping heads of the movable jaws is 45°.
The mount making machine has not been illustrated and described in the specification as such is not necessary for understanding the invention. Drive to the main shaft is given by a cam and lever mechanism or such other mechanism which has not been illustrated and described in the specification as such is also not necessary for understanding the invention. During operation of the shoulder forming mechanism, a mount with straight parallel conductor wires depending down or projecting down from the mount is held in a mount holder (not illustrated and described as such is not necessary for understanding the invention) and the mount holder is moved down and the conductor wires are positioned at opposite sides of the upright portion of the fixed jaw with the upright portion interposed between the conductor wires in close proximity thereof. On moving up the main shaft, the actuator plate moves up with the main shaft guided on the guide shaft. As a result, the one limbs of the angular members resting against the tapered heads 4c of the upstanding support members of the actuator plate tilt upwardly and the other limbs of the angular members tilt inwardly towards the upright portion of the fixed jaws about the pivots thereof The tapered surfaces at the inner ends of the clamping heads of the movable jaws press the straight conductor wires against the tapered faces at the top of the opposite sides of the upright portion of the fixed jaw and form shoulders in the conductor wires at an angle matching with the angle of taper at the inner ends of the clamping heads and at the opposite sides at the top end of the upright portion. On moving the main shaft down, the actuator plate moves down with

the main shaft and the one limbs of the angular members tilt downwardly against the tapered heads 4c of the upstanding support members and the other limbs of the angular members tilt outwardly away from the upright portion of the fixed jaw about the pivot pins and the movable jaw regain their original position.
According to the invention the shoulder forming mechanism comprises very few components and is cost effective and reliable. There is no sliding movement between the fixed jaw and movable jaws. Therefore, frictional force between the fixed jaw and clamping jaws is avoided and wear and tear of the shoulder forming mechanism is reduced. There are no possibilities for the clamping jaws to become deformed. The clamping mechanism will have increased life and continue to give trouble free performance for long period of time. The shoulders will continue to be formed uniformly for long period of time. There are only two movements for forming the shoulders namely forward and backward movements of the clamping jaws about the pivots thereof. As a result, the time for forming the shoulders is reduced and productivity is increased. The cam and roller drive mechanism for the movable jaws has been eliminated. Instead the movable jaws are operated with the actuator plate which moves due to the main shaft movement without any separate drive. As a result of this also, there is substantial reduction in the initial cost. Maintenance cost of the shoulder forming mechanism is practically eliminated. The linear adjustment of the clamping heads facilitates stroke adjustment of the movable jaws. Because of this, it is possible to make shoulders for different sizes of mounts in the shoulder forming mechanism and the shoulder forming mechanism is versatile.

The construction and configuration of the main body, actuator, fixed jaw, fixed jaw support and movable jaws can be different. The movable jaws can be of single piece construction. The guide shaft can be mounted differently. The main body is optional. Variations in the construction and configuration of the above components which are obvious to a person skilled in the art are to be construed and understood to be within the scope of the invention.

We claim :
1) A shoulder forming mechanism of a mount making machine for the manufacture of a fluorescent tube light, the mechanism comprising a horizontally disposed actuator mounted at the top of a main shaft vertically disposed for up and down movement about a vertical axis, the actuator being movable up and down with the main shaft on a guide shaft vertically disposed in the proximity of the main shaft and mounted to the bed of the mount making machine, a horizontally disposed fixed jaw support mounted at the top of the guide shaft above and in spaced apart relationship with the actuator, a fixed jaw comprising a base mounted on the fixed jaw support and a flat upright portion projecting upwardly from the base having tapered faces at the opposite sides of the top end thereof and a pair of movable jaws, each comprising an angular member disposed at each side of the upright portion and pivoted to the fixed jaw support at the corner of the angular members with one limbs of the angular members resting against the actuator and the other limbs of the angular members disposed in the proximity of the upright portion and a clamping head at the top of the other limb of each of the angular members, the clamping head having an outwardly bent inner end with a tapered surface matching with the tapered face at each side of the top end of the upright portion and adapted to press against the tapered face at the respective side of the top end of the upright portion.
2) The mechanism as claimed in claim 1, wherein the main shaft is disposed for up and down movement about a vertical axis in a tubular main body which is mounted to the bed of the mount making machine and the guide shaft is mounted on a mounting flange provided around the main body.

3) The mechanism as claimed in claim 1 or 2, wherein the actuator comprises a flat plate of stepped construction comprising a lower flat portion and a raised flat portion and a pair of lateral arms each extending laterally from the bottom of each of the raised flat portions, each of the lateral arms comprising an upstanding support member with a tapered head, one limbs of the angular members of the movable jaws resting against the tapered heads of the upstanding support members.
4) The mechanism as claimed in any one of claims 1 to 3, wherein the fixed jaw support comprises a horizontally disposed T-shaped flat member, the perpendicular portion of the T-shaped member being mounted at the top of the guide shaft and the angular members being pivoted to the lateral extensions of the T-shaped member.
5) The mechanism as claimed in any one of claims 1 to 4, wherein the opposite sides of the
top end of the upright portion and the outwardly bent inner ends of the clamping heads of
the movable jaws are tapered at 45°.
6) The mechanism as claimed in claims 1 to 5, wherein the clamping heads are detachable
and are stroke adjustably mounted at the top of the other limbs of the angular members.

7) The mechanism as claimed in claim 6, wherein the top ends of the other limbs of the angular members each comprises a channel with a mounting hole at the centre thereof and the clamping heads are linearly adjustably located in the channels at the top ends of the other limbs of the angular members and are provided with an oblong slot along the length thereof, the clamping heads being fixed to the top ends of the other limbs of the angular members with bolts tightened in the mounting holes at the top ends of the other limbs of the angular members through the oblong slots in the clamping heads against the clamping heads.