FORM 2
The Patents Act 1970 (39 of 1970)
&
The Patent Rules 2003 COMPLETE SPECIFICATION
(See Section 10 and rule \ 3)
TITLE OF THE INVENTION:


FRICTION PULLER TYPE INSERT CARRIER 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 moulding and particularly to thermoset compression moulding. The present invention more particularly relates to insert carrier assembly in compression moulding apparatus.
B) BACKGROUND OF THE INVENTION
[0002] Thermoset plastic moulded articles are used extensively in everyday life. Thermoset plastics are linear or branched polymeric materials which melt on heating and resolidify on cooling. Mould apparatus can be designed to any required shape and used repeatedly to manufacture copious amounts of moulded articles. Various moulding methods are used to manufacture articles using moulds of required shape and size. Compression moulding is used to manufacture articles of different shapes and sizes.
[0003] In compression moulding process, the thermoset plastic raw materials are placed in mould cavity. The mould is already preheated upto 165°C with the help of cartridge heaters to melt the plastic material. The plastic melts to take the shape of the cavity. The thermoset plastic cures and solidifies to the required shape and size.
[0004] Compression moulding apparatus comprises of a top half and a bottom half. The top half is secured to the moving platen of the machine and the bottom half is secured to the stationary platen of the moulding machine. The top half is the cavity side of the mould and the bottom half is the punch side of the mould.
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[0005] The die cavity designed to form the required article is provided in the top and bottom halves of the apparatus. The moving half is aligned to the fixed half to form the shape of the required moulded component. The mould apparatus is preheated. Plastic materials in the form of sheets, pellets or dough is placed on the bottom half The plastic material gets heated to 165 , which is the curing temperature of the material. The top half and bottom half are aligned and closed for the die cavity to form the required shape of the mould. The material will be held inside the mould in heated condition for few minutes till it melts and solidifies to form the required moulded component under machine tonnage.
[0006] The ejector components are provided in the top and bottom halves. The ejector components may comprise of ejector pins that are used to push the moulded component from the apparatus.
[0007] The moulded thermoset component may require fastening component for assembling a moulded component in an assembly. The thermoset material is brittle and weak to form a strong fastening thread formation. External metal threaded inserts are placed in the required positions while moulding. The threaded insert is closed to prevent the melted plastic from entering the insert.
[0008] Currently various methods are adopted to close the threaded component. The methods include screwing of the threaded insert on an insert carrier pin. The insert carrier pin has threads adapted to engage and unscrew the threaded insert from the moulded component. One method comprises of two ball catch arrangement protruding into the hole with insert carrier pin. However the arrangement is bulky and requires additional space. The arrangement cannot be used to load the threaded inserts in deep pockets. The

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threaded component is not secured strongly to avert damages when the threaded component is placed in the top half of the moulded component. Hence there is a need to provide a secure method to carry the threaded insert to the required position in the top of the mould.
C) OBJECTS OF THE INVENTION
[0009] The primary object of the present invention is to develop an insert carrier assembly to secure the threaded component to the carrier pin while placing the pin in top half of mould, bottom half of mould or both securely & precisely.
[0010] Another object of the present invention is to develop an insert carrier assembly to secure the threaded component to the carrier pin using friction.
[0011] Yet another object of the present invention is to develop an insert carrier assembly to provide a compact and simple threaded carrier component in a compression moulding apparatus.
[0012] Yet another object of the present invention is develop an insert carrier assembly to hold the threaded insert in the required position precisely.
[0013] Yet another object of the present invention is develop an insert carrier assembly to dismantle and maintain the carrier components easily.

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[0014] Yet another object of the present invention is that the insert carrier apparatus consists of fully machined items, thus avoiding any tooling requirement for the same.
[0015] 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
[0016] The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.
[0017] The various embodiments of the present invention provide an insert carrier assembly. According to one embodiment of the present invention, a friction puller type carrier assembly for mould assembly has an insert carrier provided with a male thread part and a female thread part. An insert to be molded is attached to the male thread part. A Teflon bush is attached to the female thread part of the insert carrier through a set screw. An ejector pin is attached to the insert carrier. The Teflon bush is tightened using the set screw so that the diameter of the Teflon bush is varied to hold the insert tightly inside the ejector pin.
[0018] The Teflon bush is tightened using the set screw so that the diameter of the Teflon bush is increased to hold the insert carrier tightly inside the ejector pin in the mould assembly. The Teflon bush is loosened using the set screw so that the diameter of the Teflon bush is varied to release the insert carrier from the ejector pin.
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[0019] The carrier assembly includes an insert carrier, Teflon bush and set screw. The ejector pin in the ejection assembly is modified to engage the insert carrier assembly. A drafted pocket is provided to seat the insert carrier. The insert carrier does not include any clearance to prevent the entry of melted plastic into the pockets during moulding. The insert carrier has a tapered alignment surface adapted to be engaged with a tapered mating surface provided in the projector pin. The threaded insert to be moulded is screwed into the male thread of the insert carrier. The threaded insert is fully tightened to the insert carrier. The face butting between the insert carrier and threaded insert prevents the material from flowing into the threaded region of insert.
[0020] A Teflon bush is tightened to the female thread of the insert carrier by a set screw. The bush has a taper part on the inside diameter to seat the set screw. Teflon bush has taper portion on outside diameter for entry into ejector pin. The Teflon bush is seated in a reverse draft on the diameter of the projection pin. The fitting diameter of the bush may be varied by operating the set screw. The bush resists the friction to hold the insert carrier assembly and threaded insert. The bush regains the original shape and size after the removal of external forces.
[0021] The threaded insert is placed in the required position precisely. The required component is moulded using compression. The moulded component is ejected from the moulding apparatus with the insert carrier assembly. The Insert carrier assembly is unscrewed from the component by operating the unscrewing slot provided in the insert carrier
[0022] 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.
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E) BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The othei" objects, features and advantages will occur to those skilled in the art ftQttv the following description . of the. prefetced embodiment and the accompanying, drawings in which:
[0024] FIG. I illustrates the sectional view of the modified ejector pin in the insert carrier assembly according to one embodiment of the present invention.
[0025] FIG. 2 illustrates sectional view of the insert carrier assembly according to one embodiment of the present invention.
[0026] 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 pESCRIPTION OF INVENTION
[0027] In the following detailed description, reference is made to the accompanying drawings that form 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
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departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.
[0028] The various embodiment of the present invention provides an insert carrier assembly. According to one embodiment of the present invention, a friction puller type carrier assembly for mould assembly has an insert carrier provided with a male thread part and a female thread part. An insert to be molded is attached to the male thread part. A Teflon bush is attached to the female thread part of the insert carrier through a set screw. An ejector pin is attached to the insert carrier. The Teflon bush is tightened using the set screw so that the diameter of the Teflon bush is varied to hold the insert tightly inside the ejector pin.
[0029] The Teflon bush is tightened using the set screw so that the diameter of the Teflon bush is increased to hold the insert carrier tightly inside the ejector pin in the mould assembly. The Teflon bush is loosened using the set screw so that the diameter of the Teflon bush is varied to release the insert carrier from the ejector pin.
[0030] The insert carrier has male thread to hold an insert to be mould in the mould assembly. The female thread part is arranged opposite to the male thread part in the insert carrier. The Teflon bush has a tapered part so that the Teflon bush is seated inside the draft portion of the ejector pin. The Teflon bush has got a taper entry portion formed on outer diameter portion so that the Teflon bush is inserted smoothly into the ejector pin. The Teflon bush has a taper portion on inner diameter portion for receiving and seating the set screw.
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[0031] The insert carrier assembly comprises of an insert carrier, Teflon bush and set screw. The ejector pin in the ejection assembly is modified to engage the insert carrier assembly. A drafted pocket is provided to seat the insert carrier. The insert carrier does not include any clearance to prevent the entry of melted plastic into the pockets during moulding. The insert carrier has a tapered alignment surface adapted to be engaged with a mating tapered surface in the projector pin. The threaded insert to be moulded is screwed into the male thread of insert carrier. A Teflon bush is attached to the female thread part of the insert carrier. The threaded insert is fully tightened to the insert carrier. The face butting between the insert carrier and threaded insert prevents material from flowing into the threaded region of insert.
[0032] A Teflon bush is tightened to the female thread of the insert carrier by a set screw. The bush has a taper on the inside diameter to seat the set screw. Teflon bush has a taper entry part on outside diameter for easy entry into ejector pin. The Teflon bush is seated in a reverse draft on the diameter of the projection pin. The fitting diameter of the bush may be varied by operating the set screw. The bush resists the friction to hold the insert carrier assembly and threaded insert. The bush regains the original shape and size after the removal of external forces.
[0033] The threaded insert is placed in the required position precisely. The required component is moulded using compression. The moulded component is ejected from the moulding apparatus with the insert carrier assembly. The Insert carrier assembly is unscrewed from the component by operating the set screws.
[0034] FIG. 1 illustrates the sectional view of ejector pin 1 according to one embodiment of the present invention. The ejector pin is a component of the mould assembly. The
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ejector pin 1 is modified to seat the insert carrier assembly 2. The insert carrier assembly 2 holds the threaded insert in the required position.
[0035] FIG. 2 illustrates the sectional view of insert carrier assembly 2 according to one embodiment of the present invention. The ejector pin 1 in the ejection assembly is modified to engage the insert carrier assembly 2. A drafted pocket is provided to seat the insert carrier 3. The insert carrier 3 does not comprise of any clearance to prevent entry of melted plastic into the pockets during moulding. The insert carrier 3 has a tapered alignment surface adapted to be engaged by a mating tapered surface in the projector pin 1. Threaded insert 4 to be moulded is screwed into the male thread of insert carrier 3. The threaded insert 4 is folly tightened to the insert carrier 3. The face butting between the insert carrier 4 and threaded insert 3 prevents material from flowing into the threaded region of insert.
[0036] A Teflon bush 5 is tightened to the female thread of the insert carrier 3 by a set screw 6. The Teflon bush 5 has a taper part on the inside diameter to seat the set screw 3. Teflon bush 5 has a tapered entry part on outside diameter for easy entry into ejector pin 1. The Teflon bush 5 is seated in a reverse draft on the diameter of the projection pin I. The fitting diameter of the Teflon bush 5 may be varied by operating the set screw 3. The Teflon bush 5 bulges to hold the assembly firmly by operating the set screw 3. The Teflon bush 5 resists friction to hold the insert carrier assembly 2 and threaded insert 4. The Teflon bush 5 regains the original shape and size after the removal of external forces.
[0037] The threaded insert 4 is placed in the required position precisely. The required component is moulded using compression. The moulded component is ejected from the
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moulding apparatus with the insert carrier assembly 2. The Insert carrier assembly 2 is unscrewed from the component by operating the set screws 6.
G) ADVANTAGES OF THE INVENTION
[0038] Thus the various embodiments of the present invention provide a compact design to precisely place an external metal insert in a moulded component. The threaded insert can be loaded in the top half, bottom half or both halves of the mould. The insert carrier assembly is easy to remove by ejection requiring no additional tools. Teflon bush is used to retain the insert carrier by operating set screw to bulge the bush to the required fitting diameter. Teflon bush holds the insert carrier firmly. The bush regains the original shape and size by removal of external forces.
[0039] 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.
Date: March 30, 2009. RAKESH PRABHU
Place: Bangalore. Patent Agent
[0040] 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.
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CLAIMS
What is claimed is:
1. A friction puller type carrier assembly for moulding threaded inserts, the
assembly comprising:
an insert carrier;
a Teflon bush attached to the insert carrier through a set screw; and
an ejector pin attached to the insert carrier;
wherein the Teflon bush is tightened using the set screw so that the the diameter
of the Teflon bush is varied to hold the insert tightly inside the ejector pin.
2. The assembly according to claim 1, wherein the Teflon bush is tightened using the set screw so that the diameter of the Teflon bush is increased to hold the insert carrier tightly inside the ejector pin in the mould assembly.
3. The assembly according to claim 1, wherein the Teflon bush is loosened using the set screw so that the diameter of the Teflon bush is varied to release the insert carrier from the ejector pin after moulding operation.
4. The assembly according to claim 1, wherein the insert carrier has male thread to hold a threaded insert to be mould in the mould assembly.
5. The assembly according to claim 1, wherein the insert carrier has female thread arranged opposite to the male thread.
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6. The assembly according to claim I. wherein the Teflon bush is attached to the female thread using the set screw.
7. The assembly according to claim 1, wherein the Teflon bush has a tapered portion for seating the insert precisely in the ejector pin.
8. The assembly according to claim 1, wherein the Teflon bush has got a taper portion on outer diameter portion so that the Teflon bush is inserted smoothly into the ejector pin.
9. The assembly according to claim 1, wherein the Teflon bush has a taper portion on inner diameter portion for receiving and seating the set screw.
10. The assembly according to claim 1, wherein the set screw is mounted on the insert carrier to tighten the Teflon bush to make the Teflon bush to interfere with the ejector pin.
11. The assembly according to claim 1, wherein the ejector pin has a profile to receive and hold the insert carrier along with the Teflon bush.
12. The assembly according to claim 1, wherein the ejector pin has reverse draft to receive the Teflon bush to hold the insert carrier Firmly. ( /j
RAKESH PRABHU
Patent Agent
Date: March 30, 2009 Place: Bangalore.
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