FORM 2
The Patents Act 1970
(39 of 1970)
&
The Patent Rules 2003 COMPLETE SPECIFICATION
(See Section 10 and rule 13)
TITLE OF THE INVENTION:


A SYSTEM AND METHOD FOR FORMING BLADE FINGER
ASSEMBLY
APPLICANT:
LARSEN & TOUBRO LIMITED
L&T House, Ballard Estate, P.O. Box No. 278,
Mumbai, 400 001, Maharashtra . INDIA.
PREAMBLE OF THE DESCRIPTION:
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

A) TECHNICAL FIELD
[0001] The present invention generally relates to tool forming die and particularly to tools for forming blade finger assembly. More particularly it relates to tool for forming blade and inserting tube with a single mechanism.
B) BACKGROUND OF THE INVENTION
[0002] The forming and assembling tools are generally used for progressively forming and inserting a rigid material or blade in a hollow malleable tubular profile to achieve a single rigid assembly. The blade insertion process is used for simultaneously forming and progressively assembling two parts such as a blade-Pole finger and a tube together to form a partial finger Assembly. In this method, a hollow profiled tube is flattened using two rollers to the extent to accommodate an oversized blade pole finger inside it. Also to accommodate Silver coated copper braids on the other side, the tube couldn't be flattened throughout. Therefore in Conventional method the blade insertion process is divided in two stages. A half insertion, in which the tube is formed and the blade is inserted simultaneously half way, leaving some of the portion of the tube un-deformed and a full insertion, in which the remaining portion of blade is inserted in the tube without further tube-forming.


[0003] More over, during full insertion the forming rollers should not be in contact with the tube to avoid tearing of tube. Because of this constraint earlier in conventional method two different tools were used for Blade insertion.
[0004] The conventional method available uses complex methods for assembling the blade and tube. Hence there is a need to simplify the forming and assembling process by combining half insertion and full insertion process in a single tool. Also it is necessary to avoid tearing of the forming tube during full insertion. These problems have been solved in the present invention.
C) OBJECTS OF THE INVENTION
[0005] The primary object of the present invention is to provide a full blade component insertion tool for simultaneously forming and assembling of a blade-pole finger and a tube in one tool using a single-action cam.
[0006] Another object of the present invention is to provide a full blade component insertion to combine half and full insertion process in single tool using cam-follower mechanism.
[0007] Yet another object of the present invention is to provide full blade component insertion tool to make the cam and the roller inactive during full blade insertion and to avoid the tearing of tube during full blade insertion.


[0008] Yet another object of the present invention is to provide a full blade insertion tool to simplify the forming and assembling during loading and unloading of the tool and to reduce the effort required to form a finger assembly.
[0009] These and other objects and advantages of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.
D) SUMMARY OF THE INVENTION
[0010] The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.
[0011] The various embodiments of the present invention provide a simultaneous forming and assembling of a blade-pole finger and a tube in one tool using a single-action cam. It combines half and full blade insertion process in single tool using a cam-follower mechanism. The cam-follower mechanism comprises of a cam, a slide and a follower. It includes a roller which is actuated by single action cam.
[0012] According to one embodiment of the present invention, a system for forming finger assembly has two cam mechanisms mounted on the top plate. Two Cam slides moves between the guide plates mounted on the heel blocks. Two cam followers are


mounted respectively on the two cam slides. A spring mechanism is provided on each cam slide. Two tube forming rollers are movably mounted on the two cam slides respectively.
[0013] The cam mechanism and the cam follower control the movement of the rollers during the finger assembly formation process. The cam mechanisms and the cam followers drive the rollers to move towards each other to flatten a tube during the half insertion of a blade into the tube. The cam mechanism and cam follower control the movement of the rollers to move the rollers away from each other to prevent the deformation of the tube after the insertion of the blade into the tube.
[0014] According to an embodiment of the present invention, the forming and the assembling tool comprises of a top half and a bottom half. The bottom half includes a die block mounted on base plate to locate the blade-pole finger. A pair of heel blocks is mounted on either side of the die block. A cam slide with a cam follower and roller is provided on the top of the heel blocks. The cam slide includes a spring mechanism to maintain the standard gap between the rollers during loading and unloading of the component. A nest plate with through pocket to load the tube from top is mounted on the base plate. The through pocket in the nest plate is of the same profile as that of the component to be loaded, it guides the tube during the loading. The top half comprises of a Top plate, cams and a cam holders to hold the cam. The top half also includes a central forming punch mounted in the holder plate, which registers and guides the tube during forming operation.


[0015] According to one embodiment of the present invention the cam is designed in such a way to support the smooth entry of the cam inside the slide. A straight portion of the cam ensures heeling of the cam against the heel block before the forming action starts, to avoid its deflection. A standard step on cam brings the rollers to their forming position and keeps them at that position for next standard travel inside the heel block. The step thereafter disengages the cam and makes rollers inactive during full blade insertion.
[0016] According to one embodiment of the present invention, the follower surface is made round and polished to have line contact with the cam so as to avoid wear and cold welding. The follower is mounted on the cam slide using a pin about which it can swivel. During the return stroke of the cam, the step in cam comes in contact with the step in follower causing the follower to swivel. This makes the cam and the rollers inactive. According to one embodiment of the present invention, the cam followers as well as the rollers are mounted on the slide. The oblong hole in the slide helps in maintaining the required different gaps between the rollers at different stages of tube forming.
[0017] According to embodiment of the present invention during half insertion the cam keeps the rollers in contact with the tube to flatten it and during full insertion the cam withdraws the rollers from tube without further forming it. In order to avoid damage of the component during the return stroke the follower of cam swivels about its hinge point and makes the cam inactive. Initially when the tool is in open condition the cam slide is pulled backwards by the spring mechanism and a standard gap is maintained between the
31 MAR 2009

rollers. The rollers are spaced apart with a standard gap between them to facilitate loading and unloading of the component. The maximum gap between the rollers is maintained to provide resting for the tube of standard size.
[0018] Initially the operator loads the blade-pole finger in the slot provided on the die block. Then the tube is loaded through the nest plate and rested on the rollers. The nest plate is of the same profile as that of the component to be loaded, it guides the tube during the loading. After loading the component, operator applies a stroke to move the top plate with cam downwards. As the top plate starts moving down, the cams come into action which pushes the rollers to its forming position maintaining a standard distance between them. With further movement of cam the projection on the punch enters the tube and registers it. After registering the tube in proper position, the forming punch forces the tube against the rollers. At this stage the forming load is applied by the rollers which are in stationary position due to cam engagement. The tube is pressed between the rollers and gets formed into a flat shape such that it accommodates the oversized blade inside it. This movement continues for a standard distance of around 34 mm.
[0019] Once the standard distance is reached further forming of the tube is not desirable. Hence the rollers are retracted at this-stage. An intentional step is provided on the cam which results in disengagement of follower and retracts the rollers back by spring mechanism. As the cam moves further down, the forming punch pushes the tube against the blade to obtain full insertion. As the followers are disengaged from the cam the rollers
31 MAR 2009

'do not apply any forming load on the tube during this travel. At the end of downward stroke the blade gets fully inserted in the tube as required.
[0020] The followers are made swiveling to avoid the forming of tube during return stroke of cams, the followers are made swiveling It ensures that during the return stroke, the follower should not follow the path of cam to avoid possible damage of the component. At the end of return stroke, due to spring loaded mechanism the roller and follower assembly comes to its original position creating spaces for loading and unloading of the components. A separate ejection mechanism is used for unloading the finger assembly from the tool.
[0021] The present invention provides an improved forming and assembling tools for forming and inserting a rigid material such as Blade in a hollow malleable tubular profile to achieve a single rigid assembly. Since the cam and the roller in the present invention are inactive during full blade insertion it avoids tearing of the tube.
E) BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The other objects, features and advantages will occur to those skilled in the art from the following description of the preferred embodiment and the accompanying drawings in which:


' [0023] FIG. I shows a cross sectional view of the assembly of full blade component insertion tool in open condition (before loading or forming) according to one embodiment of the present invention.
[0024] FIG. 2 shows a cross sectional view of the assembly of the full blade component insertion tool with blade-pole finger mounted on the die block according to one embodiment of the present invention.
[0025] FIG. 3 shows a cross sectional view of the assembly of the full blade component insertion tool with the tube being loaded between the rollers according to one embodiment of the present invention.
[0026] FIG. 4 shows a cross sectional enlarged view of the loading of tube between the rollers according to one embodiment of the present invention.
[0027] FIG. 5 shows a cross sectional view of the full blade component insertion tool during commencement of the cam-follower engagement according to one embodiment of the present invention.
[0028] FIG. 6 shows a cross sectional view of the assembly of full blade component insertion tool at the end of half insertion according to one embodiment of the present invention.

[0029] FIG. 7 shows a cross sectional view of the assembly of full blade component insertion tool when the cam-follower disengages and retracts rollers from forming position according to one embodiment of the present invention.
[0030] FIG. 8 shows a cross sectional view of the assembly of full blade component insertion tool when the follower swivels during return stroke (full insertion) according to one embodiment of the present invention.
[0031] Although specific features of the present invention are shown in some drawings and not in others. This is done for convenience only as each feature may be combined with any or all of the other features in accordance with the present invention.
F) DETAILED DESCRIPTION OF THE INVENTION
[0032] In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which the specific embodiments that may be practiced is shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and it is to be understood that the logical, mechanical and other changes may be made without departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.
31 MAR 2009

[0033] The various embodiments of the present invention provide a full blade component insertion tool for simultaneous forming and assembling of a blade-pole finger and a tube in one tool using a single-action cam. It combines half and full blade insertion process in single tool using a cam-follower mechanism. The cam-follower mechanism comprises of a cam, a slide and a follower. It includes a roller which is actuated by single action cam.
[0034] According to one embodiment of the present invention, a system for forming finger assembly has two cam mechanisms mounted on the Cam holder plate on top half. Two cam-slides moves between the guide plates mounted on the heel blocks. Two cam followers are mounted respectively on the two cam slides. A spring mechanism is provided on each cam slide. Two tube forming rollers are movably mounted on the two cam slides respectively.
[0035] The cam mechanism and the cam follower control the movement of the rollers during the finger assembly formation process. The cam mechanisms and the cam followers drive the rollers to move towards each other to flatten a tube during the half insertion of a blade into the tube. The cam mechanism and cam follower control the movement of the rollers to move the rollers away from each other to prevent the deformation of the tube after the insertion of the blade into the tube.
[0036] The cam mechanism has a profile including a draft part, straight part and a step part. The draft part of the cam mechanism mates with the cam follower to enable the smooth entry of the cam mechanism into the slide. The straight part of the cam

mechanism mates with the cam follower to make the rollers to press a tube to flatten the tube during the half insertion of the blade into the tube. An intentional step is provided on the cam to disengage the cam followers from the cam to make the rollers inactive during the full insertion of the blade into the tube. The cam follower is mounted on the cam slide through a pin so that the cam follower swivels about the pin axis. The step part of the cam comes in contact with the cam follower to make the follower to swivel thereby keeping the cam and rollers inactive during return stroke also.
[0037] According to an embodiment of the present invention the forming and the assembling tool comprises of a top plate and a base plate. The base plate includes a die pole to receive the blade-pole finger. A pair of heel blocks is. mounted on either side of the die block. A cam slide with a cam follower and roller is provided on the top of the heel blocks. The cam slide includes a spring mechanism to maintain the standard gap between the rollers during loading and unloading of the component. A nest plate with through pocket to load the tube from top is mounted on the base plate. The through pocket in the nest plate is of the same profile as that of the component to be loaded, it guides the tube during the loading. The top half comprises of a Top plate, cams and a cam holders to hold the cam. The top half also includes a central forming punch mounted in the holder plate, which registers and guides the tube during forming operation.
[0038] During half insertion the cam keeps the rollers in contact with the tube to flatten it and during full insertion the cam withdraws the rollers from tube without further forming it. In order to avoid damage of the component during the return stroke, the follower of


cam swivels about its hinge point and makes the cam inactive. Initially when the tool is in open condition the cam slide is pulled backwards by the spring mechanism and a standard gap is maintained between the rollers. The rollers are spaced apart with a standard gap between them to facilitate loading unloading of the component. The maximum gap between the rollers is maintained to provide resting for the tube of standard size.
[0039] FIG. 1 shows a cross sectional view of the assembly of full blade component insertion tool in open condition (before loading or forming) according to one embodiment of the present invention. It shows the base plate 101 and top plate 108. The base plate 101 includes a die pole 110 to receive the blade-pole finger. A pair of heel blocks 102 is mounted on either side of the die block 110. A cam slide 103 with a cam follower 105 and roller 111 is provided on the top of the heel blocks 102. The cam slide 103 includes a spring mechanism to maintain the standard gap between the rollers 111 during loading and unloading of the component. The rollers are mounted on the rolling pin 112. A nest plate 109 with a through pocket to load the tube from top is mounted on the base plate. The through pocket in the nest plate 109 is of the same profile as that of the component to be loaded, it guides the tube during the loading. The top half comprises of a Top plate 108, cams 104 and a cam holders 107 to hold the cam. The top half also includes a central forming punch 106 mounted in the holder plate, which registers and guides the tube during forming operation. Initially the cam slide 103 is pulled backwards by the spring mechanism and the required gap of 10.5 mm is maintained between the rollers 111 to provide enough support to the tube as shown in figure 1.


[0040] The cam 104 is designed in such a way as to support the smooth entry of the cam 104 inside the slide 103. A straight portion of the cam 104 ensures heeling of the cam 104 against the heel block 102 before the forming action starts, to avoid its deflection. A standard profile step on cam brings the rollers 111 to their forming position and keeps them at that position for next standard travel inside the heel block 102. The step thereafter disengages the cam 104 and makes rollers 111 inactive during full blade insertion. The follower 105 surface is made round and polished to have line contact with the cam 104 so as to avoid wear and cold welding. The follower 105 is mounted on the cam slide 103 using a pin about which it can swivel. The rollers are also mounted on the same slide. During the return stroke of the cam 104, the step in cam 104 comes in contact with the step in follower 105 causing the follower 105 to swivel. This makes the cam 104 and the rollers 111 inactive. The cam followers 105 as well as the rollers 111 are mounted on the slide 103. The oblong hole in the slide 103 helps in maintaining the required different gaps between the rollers 111 at different stages of tube forming.
[0041] FIG. 2 shows a cross sectional view of the assembly of the full blade component insertion tool. According to one embodiment of the present invention, the blade-pole finger is located in the slot on the die block. Initially operator loads the blade-pole finger 201 on the die block 110.
[0042] FIG. 3 shows a cross sectional view of the assembly of the full blade component insertion tool with the tube being loaded between the rollers according to one embodiment of the present invention. Once the blade-pole finger 201 is loaded on the die


block 110, then the tube 301 is loaded through the nest plate 109 and rested on the rollers 111 as shown in figure 3. A nest plate 109 with a through pocket to load the tube from top is mounted on the base plate. The through pocket in the nest plate 109 is of the same profile as that of the component to be loaded, it guides the tube during the loading. For tube 301 forming the standard gap between the rollers 111 should be maintained and this should be done before the forming punch starts pushing the tube 301. As the forming of tube 301 starts, this standard gap should be maintained for next 34mm travel of punch that is till the end of half insertion process.
[0043] FIG. 4 shows a cross sectional enlarged view of the loading of tube between the rollers according to one embodiment of the present invention. As shown in figure 4, the rollers 111 are spaced apart with a standard gap between them to facilitate loading and unloading of the tube 301. The maximum gap between the rollers 111 is maintained to provide resting for the tube 301 of standard size. The tube 301 is loaded through the nest plate 109 and rested on the rollers 111. The nest plate 109 is of the same profile as that of the component to be loaded, it guides the tube 301 during the loading.
[0044] FIG .5 shows a cross sectional view of the full blade component insertion tool during commencement of the cam-follower engagement according to one embodiment of the present invention. As the cam engages with the followers, a standard gap is maintained between the rollers. This standard gap is maintained for next 34 mm of travel of top plate.


[0045] FIG. 6 shows a cross sectional view of the assembly of full blade component insertion tool at the end of half insertion according to one embodiment of the present invention. With respect to figure 6. as the top plate 108 starts moving down, the cams 104 come into action which pushes the rollers 111 to its forming position maintaining a standard distance between them. With further movement of cam 104 the projection on the punch 106 enters the tube 301 and registers it. After registering the tube 301 in proper position, the forming punch 106 forces the tube 301 against the rollers 111. At this stage the forming load is applied by the rollers 11 lnwhich are in stationary position due to cam 104 engagement. The tube 301 is pressed between the rollers 111 and gets formed into a flat shape such that it accommodates the oversized blade inside it. This movement continues for a standard distance of around 34 mm. To avoid tearing of tube 301 during further insertion, the rollers 111 should not be in contact with the tube 301. As the formed component is retained in the bottom half, the rollers lllnwill not damage the formed component during return stroke.
[0046] FIG. 7 shows a cross sectional view of the assembly of full blade component insertion tool when the cam-follower disengages and retracts rollers from forming position according to one embodiment of the present invention. Once the standard distance of the tube 301 is reached, further forming of the tube 301 is not desirable. Hence the rollers 111 are retracted at this stage. An intentional step is provided on the cam 104 which results in disengagement of follower 105 and retracts the rollers 111 back by spring mechanism. As the cam 104 moves further down, the forming punch 106 pushes the tube 301 against the blade to obtain Ml insertion. As the followers 104 are


" disengaged from the cam 105 the rollers do not apply any forming load on the tube 301 during this travel. At the end of downward stroke the blade gets fully inserted in the tube 301 as required.
[0047] FIG. 8 shows a cross sectional view of the assembly of full blade component insertion tool when the follower swivels during return stroke (full insertion) according to one embodiment of the present invention. As shown in figure 8, to avoid the forming of tube 301 during return stroke of Cams 104, the followers 105 are made swiveling. It ensures that during the return stroke, the follower 105 should not follow the path of cam 104 to avoid possible damage of the component. At the end of return stroke, due to spring loaded mechanism the roller 111 and follower 105 assembly comes to its original position creating spaces for loading and unloading of the components. A separate ejection mechanism is used for unloading the finger assembly from the tool.
G) ADVANTAGES OF THE INVENTION
[0048] The various embodiments of the present invention provide a full blade component insertion tool for simultaneous forming and assembling of a blade-pole finger and a tube in one tool using a single-action cam. It combines the half and full insertion process in single tool using cam-follower mechanism. The Blade Insertion Tool makes the rollers inactive to avoid tearing of the tube during full insertion. It also makes the cam inactive during return stroke to avoid possible damage to the formed tube. It simplifies the forming and assembling during loading and unloading of the tool and to reduce the effort required to form a finger assembly.
31 MAR 2009

[0049] Although the invention is described with various specific embodiments, it will be obvious for a person skilled in the art to practice the invention with modifications. However, all such modifications are deemed to be within the scope of the claims.

[0050] It is also to be understood that the following claims are intended to cover all of the generic and specific features of the present invention described herein and all the statements of the scope of the invention which as a matter of language might be said to fall there between.
Date: March 30, 2009. RAKESH PRABHU
Place: Bangalore. Patent Agent

CLAIMS
What is claimed is:
1. A system for forming finger assembly including tube and blade pole finger in tool
forming die including a base plate, two heel blocks, die plate and top plate, the
system comprising:
two cam mechanisms mounted on the top plate;
two cam slides mounted respectively on the two heel blocks;
two cam followers mounted respectively on the two cam slides;
two spring mechanisms provided respectively on the two cam slides; and
two tube forming rollers movably mounted on the two cam slides respectively;
wherein the cam mechanism and the cam follower control the movement of the
rollers during the ringer assembly formation process.
2. The system according to claim 1, wherein the cam mechanisms and the cam followers drive the rollers to move towards each other to flatten a tube during the half insertion of a blade into the tube.
3. the system according to claim 1, wherein the cam mechanism and cam follower control the movement of the rollers to move the rollers away from each other to prevent the deformation of the tube after the insertion of the blade into the tube.

4. The system according to claim 1, wherein the cam mechanism has a profile, which includes an entry draft, a straight portion, a profile portion and a step.
5. The system according to claim4, wherein the draft part of the cam mechanism mates with the cam follower to enable the smooth entry of the cam mechanism into the slide.
6. The system according to claim 4, wherein the straight portion of the cam ensures heeling of the cam against the heel block well before the forming action starts, to avoid its deflection.
7. The system according to claim 4, wherein the profile portion of the cam mechanism mates with the cam follower to make the rollers to press a tube to flatten the tube during the half insertion of the blade into the tube.
8. The system according to claim 1, wherein the cam follower is disengaged from the step part of the cam to make the rollers inactive.
9. The system according to claim 1. wherein the cam follower is mounted on the cam slide through a pin so that the cam follower swivels about the pin axis.


10. The system according to claim 1, wherein the step part of the cam comes in contact with the cam follower to make the follower to swivel thereby making the cam and rollers inactive.
Dated this the 30th day of March 2009

RAKESH PRABHU Patent Agent,
ALMT Legal,
#2, Lavelle Road, Bangalore-560 001
To,
The Controller of Patents, The Patent Office, Mumbai