FORM 2
THE PATENTS ACT, 1970 PROVISIONAL SPECIFICATION
(See Section 10)
DOUBLE EJECTION MECHANISM FOR MOULDS AND DIES
Numbered as dated
INVENTORS:
a) NITIN J.PAGAR
b) VISHAL PUNWAR
c) HARISH. S. MISTRY
APPLICANT:
M/s. LARSEN & TOUBRO LIMITED
L&T House, Ballard Estate, P.O. Box No 278,
Mumbai, 400 001, Maharashtra,
INDIA

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
NATURE OF THE INVENTION

DOUBLE EJECTION MECHANISM FOR MOULDS AND DIES
A) Technical field
[0001] The embodiments herein generally relate to plastic mould and die casting, and more specifically to an ejection mechanism used in moulds or die casting dies where metal inserts are moulded / casted with components.
B) Background
[0002] Plastic moulds and die casting dies are used to give required shape to a molten material after solidification. Some times component design is such that some metal inserts are to be moulded / casted as an integral part of the component. This requires special arrangement for placement, location and ejection of the insert along with component from the mould / die.
[0003] There are various conventional methods for loading and ejecting the insert from the mould like insert carrier pin method, ejector pin method etc.
[0004] Insert carrier pin method as shown in FIG.l. There is an insert carrier pin A i.e. a special ejector pin having cavity for the location of insert C. This pin is located in the ejector plate B and can move along with other ejector pins. Insert C is loaded in the insert carrier pin A when ejector plate B is in top most
I

position. After loading the insert C, ejector plate B is brought down. Thus, this method provides ease of loading insert C in deep as well as shallow cavity mould. After moulding when ejector plate B is moved up to eject the component D, insert also moves along with component D. But, component D cannot be ejected from carrier A, as there is no relative movement between insert C and insert carrier pin A. Hence, it has to be removed manually. As the insert C and insert carrier pin A have some clearance for loading, some material may creep in to the carrier pin cavity during moulding. This makes removal of component D more difficult. Hence, though this method is good for locating an insert C, it is bad for ejection. The working of this method is depicted in FIG1.
[0005] Ejector Pin method as shown in fig.2, a pocket is provided, directly in the punch / die E, to locate the insert C and an ejector pin A is provided directly below the insert C to eject the component D along with the insert C. As there is relative movement between the insert locating cavity E and the insert C, this mechanism eases the ejection of the component D along with insert C. In this mechanism, as the insert C is located directly in the punch / die E, it is difficult to locate the insert C if the pocket is located deep in the punch / die E. As the insert C and locating cavity for insert E have clearance, some material may creep in at the time of moulding.
[0006] While the conventional solutions are advantageous for their intended purposes, the existing state of the art generally does not provide adequate solutions for loading and ejection of insert together.
2

[0007] Hence, there is a need to develop an ejection mechanism that can easily eject the component along with insert from the punch / die. Object of the invention
[0008] An object of the invention is to provide mechanism for loading and placing the insert in the mould / die and ejecting component along with metal insert from the mould / die.
[0009] An object of the invention is to provide a mechanism to facilitate ease of insert loading in shallow as well as deep cavity moulds
[0010] Another object of the invention is to provide a mechanism to ensure that the insert coming to its desired position before next cycle starts.
C) Summary
[0011] The embodiments herein provide a mechanism for loading and placing the insert in the mould / die and ejecting component along with metal insert from the mould / die. The invention relates to the field of plastic mould and die casting dies, which are used to give required shape to a molten material after solidification. Some times component design is such that some metal inserts are to be moulded / casted as an integral part of the component. The invention relates to an ejection mechanism used in aforesaid moulds or die
3

casting dies where such metal inserts are moulded / casted with components. This requires special arrangement for placement, location and ejection of the insert along with component from the mould / die. The invention also relates to the novel mechanism for loading and placing the insert in the mould / die and ejecting component along with metal insert from the mould / die. Mechanism of the invention is carried out in two stages: in first stage ensures ease of location and second stage ensures easy ejection of insert along with component.
[0012] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
D) Detailed description of drawings
[0013] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and
4

processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0014] FIG. 3 illustrates ejector plate of the mould/die along with the other ejector pins.
[0015] FIG. 4 illustrates complete mechanism. A sleeve 4 provides housing for insert 3 to be moulded. Sleeve 4 is placed between punch 5 and punch housing 8. Diameter of the counter bore in punch housing 8 is selected such that collar of sleeve 4 can rest on it and contact area is enough to sustain shearing load during moulding. Ejector pin 7 is inserted in to the sleeve along with spring 9 that is positioned between collar of sleeve 4 and collar of ejector pin 7. A cross pin 6 is inserted between sleeve 4 and ejector pin 7. To retain ejector pin 7 in retainer plate 10 an ejector collar 11 is fixed with the counter sunk screw 13. This ejector plate assembly is backed by ejector Backing plate 12. Insert spring 9 on ejector pin 7 till it rests on its collar. Sleev 4 is inserted on ejector 7 till it rests on spring 9. Hole on ejector 7 is matched to the slot on sleeve 4 and is put cross pin 6 in between them. This whole assembly is inserted in a pocket formed in a die housing 8. Die block 5 is inserted and tightened on sleeve 4. Then die block assembly is turned down and assembly of ejector plate is carried out. End of ejector is inserted in ejector holder plate 10 and ejector collar 11 is
5

coupled to it Then assembling of other ejector pins is carried out.
[0016] Mould is open and ejector backup plate 12 is at non-actuated position shown in FIG 5.
[0017] Ejector backup plate 12 is moved by distance 'X' which moves sleeve 4, cross pin 6, ejector 7 and spring 9 by amount 'X’ as shown in FIG 6. Spring 9 would not get compressed, as collar of sleeve 4 will not rest against die insert 5 for distance 'X'.
[0018] As sleeve 4 has come out of cavity 5 by distance 'X' so metal insert 3 is loaded easily in the insert carrier as shown in FIG 7.
[0019] Ejector backup plate 12 is again moved back by distance 'X' which moves sleeve 4, cross pin 6, ejector 7, metal insert 3 and spring 9 by amount ‘X' to non actuated position as shown in FIG 8.
[0020] Mould is charged with predetermined quantity of moulding material, closed and heated up to Curie temperature in case of compression and transfer mould. If it is a Injection mould then mould is closed and moulding material is injected in the die and allowed to cool as shown in FIG 9.
[0021] This Curie temperature is maintained for a curie time and a part is formed in the space formed between punch 1 and cavity 5 as shown in FIG 10
6

[0022] FIG 11 illustrates open position of the mould.
[0023] Ejector backup plate 12 is moved by distance 'X' which moves sleeve 4, cross pin 6, ejector 7 and spring 9 by amount 'X'. This action moves part 2 out of cavity 5 as shown in FIG 12. But part 2 does not come out of sleeve 4. Spring 9 does not get compressed, as collar of sleeve 4 does not rest against die insert 5.
[0024] Ejector backup plate 12 is moved by distance ‘Y’ which now cannot move sleeve 4 so spring 9 get compressed by ‘Y’ Ejector 7 comes out of sleeve 4 thus pushes metal insert 2 and component 2 out of sleeve 4 as shown in FIG 13.
[0025] FIG 14 illustrates the removal of component 2.
[0026] Ejector backup plate 12 is moved back by distance ‘y’ which uncompresses the spring 9 and moves ejector 7 back in sleeve 4 creating space to load metal insert 3 as shown in FIG 15.
[0027] Metal insert 3 is loaded and mould is ready for next cycle of operation as shown in FIG 16.
[0028] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that, others can, by applying current knowledge, readily modify and/or adapt for various
7

applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the appended claims.
The detailed scope and monopoly of the invention shall be more clearly ascertained at the time of filing Complete Specification
Dated this the 28TH day of March, 2007
Rakesh Prabhu,
Patent Agent, ALMT Legal,
No.2, Lavelle Road, Bangalore-560 001, INDIA
To,
The Controller of Patents,
The Patent office,
At Mumbai
8

Abstract
A mechanism for loading and placing the insert in the mould / die and ejecting component along with metal insert from the mould / die. Some times component design is such that some metal inserts are moulded / casted as an integral part of the component. The invention relates to an ejection mechanism used in aforesaid moulds or die casting dies where such metal inserts are moulded / casted with components. This requires special arrangement for placement, location and ejection of the insert along with component from the mould / die. The invention also details mechanism for loading and placing the insert in the mould / die and ejecting component along with metal insert from the mould / die. Mechanism of the invention is carried out in two stages: in first stage ensures ease of location and second stage ensures easy ejection of insert along with component.
9