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:
AIR EJECTOR MECHANISM FOR PRESS TOOLS
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 a press tool assembly and particularly to the press tools used for processing coils or strips in progressive punching operations executed during the manufacturing process of sheet metal components used in applications such as electrical/electronic products, automobiles, watches etc. The present invention more particularly relates to air ejection system for ejecting components out of the tool before the starting of the next stroke.
B) BACKGROUND OF THE INVENTION
[0002] Press working is one of the major processing techniques for converting a sheet metal into the sheet metal parts of different shapes. The sheet metal parts are required for different applications such as electrical/ electronic products, automobiles, watches etc. The sheet metal is punched between two parts called a punch and a die. The die profile is the female profile intentionally kept bigger than the punch profile by a uniform gap called cutting clearance.
[0003] The press tool mainly consists of two halves, namely a fixed bottom half and a moving top half. The fixed bottom half is secured to the stationary bolster plate of a mechanical press. The bottom half comprises of an arrangement to guide the strip/coil, the die cavities, the guide pillars for alignment of both the halves etc. The top moving half is clamped to the moving ram of the mechanical press and it comprises a number of circular and non circular cutting and non cutting elements called punches. The punches move up and down along with the moving ram of the mechanical press and they are guided in cavities made in a plate called Stripper plate. During the downward movement, the punches penetrate the sheet metal and enter the

die cavity thus pushing the sheet metal scrap displaced by the cutting punch into the lower half of the tool. One downward and return upward movement of the top half of press tool is called as a stroke of the press tool. The surrounding metal clings to the body of the cutting punches during the downward stroke. The same is stripped off by the stripper plate during the upward stroke of the punches.
[0004] Press working is one of the major processing techniques for converting a sheet metal into the sheet metal parts of different shapes. The sheet metal parts are required for different applications such as electrical/ electronic products, automobiles, watches etc. The sheet metal is punched between two parts called punch and die.
[0005] The press tools are of multi-station type or single station type. In a multi-station tool, the strip moves from one end of the strip guides to the other end. It moves progressively by a fixed distance called pitch after every stroke of the mechanical press. At each stage during the movement of strip, different punching operations are carried out on the strip / coil leading to the completion of the stamping profile in the last stage. The stripper in the press tools is designed to move as the press ram reaches the bottom of its stroke. Usually the strippers are of two types such as a fixed stripper and a floating stripper. The fixed stripper is fixed to the bottom half of the press tool and the floating stripper is fixed to the top half of the press tool to hold down the stock during the stamping operation and strip the stock.
[0006] The component is a separate element, free from the strip / coil after the parting operation. This remains on the top of the die plate after parting operation. This is to be removed from the press tool before the next stroke of press or else the component which remains on the die and will get damaged and damage the tool elements and strip in the next stroke. So the components are to be ejected / removed out of the tool before the next stroke takes place.

[0007] In a conventional press tool assembly, a remotely located sealed enclosure is provided. The sealed enclosure is filled with a compressible gas and into which an incompressible fluid is introduced through a pressure line. The other end of the pressure line is connected to a conventional hydraulic cylinder provided with a piston which is connected to an ejector pin. During the closure of the press, the ejector pin is forced upwards thereby forcing a fluid into the remotely located sealed enclosure. A controllable directional valve entraps the forcibly introduced incompressible fluid and the energy is stored in compressing the compressible fluid. After the opening of the press, the controllable valve is opened at a time in which an automated receiving tray has been inserted to receive the part, to eject a component from the press.
[0008] Sometimes the assembly includes a number of ejection pins distributed over the surface of the press tool. Each ejection pin is arranged so that its tip lies at a level which is not higher than the aforementioned press surface during the pressing operation. When the tool is opened after the completion of a pressing operation, the component is ejected from the tool with the tip of each ejection pin. Each ejection pin is operatively connected via a piston rod to a hydraulic piston. The piston is capable of axial displacement in a hydraulic cylinder, which is filled with an incompressible fluid in space between the piston and an end wall of the cylinder.
[0009] In some press tools, the component is removed by the supply of forced air. The air ejectors are provided at convenient places in the die. Air pressure and direction of air supply is effective on the component and it is ensured that no hindrances / obstacles are in the passage of the component removal. The ejector is made in such a way that the air is always supplied in the required direction at required time and is placed in the tool in the required orientation only. Continuous supply of air will cause problems for feeding and may displace the component anywhere in the tool during working, since punches and other tooling elements becomes an obstacles

for the smooth air flow in the downward stroke. So air supply is to be stopped during the downward stroke.
[0010] In the currently available air ejection systems, the component was ejected by continuous supply of air. This resulted in uneven air supply since tooling elements becomes an obstacle for the smooth air flow inside the tool and component getting displaced due to this. This reduced the effectiveness of the final ejection since component may cling to any of the tool elements and may not get ejected out of the tool before the next stroke. This caused accidents and darnaged the tool elements and components. This also created difficulty in collecting the component after parting out. So air supply is to be stopped during the downward stroke.
[0011] Thus the currently available methods and arrangements for the removal of components from the press tool are very complicated and needs regular maintenance. Also in some cases, the components are displaced anywhere in the tool during working.
[0012] Hence there is a need to provide an air ejection mechanism in which the air supply from the mechanism is stopped during the downward movement of the press (before the punching operation and during the punching operation) and the air is passed only during the upward stroke of the press to eject the component out of the tool before the start of the next stroke.
[0013] The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.

C) OBJECT OF THE INVENTION
[0014] The primary object of the present invention is to develop an air ejection system for ejecting the components from press tools positively after every stroke.
[0015] Another object of the present invention is to develop an air ejection system for ejecting components and slugs from automated production press tooling.
[0016] Yet another object of the present invention is to develop an air ejection system for supplying air for ejecting the components from press tools only during the upward stroke of the press tool.
[0017] 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
[0018] The various embodiments of the present invention provide a system and method for ejecting of components from the press tool. According to one embodiment of the present invention, an air ejector mechanism for press tools has an air ejector unit provided in a die plate in a press tool. A spring is arranged below the air ejector unit. A nozzle is connected to the air ejector unit. The air ejector unit is projected outside the die plate by the spring during the upward movement of a press unit to discharge air to eject a component from the press tool.
[0019] The air ejector unit is arranged inside a hole in the die plate. The air ejector unit is moved inside the die hole in the die plate during the downward movement of the press unit to block the supply of air from the air ejector unit.

[0020] The air ejector unit has an elongated air ejector. The elongated air ejector is a cylindrical element. The air ejector has a step at the bottom to receive the spring. The step is provided to act as a stopper for upward movement. The air ejector has a blind hole at the centre. The blind hole is extended from the bottom side of the air ejector. The air ejector has a flat surface at one face. The air ejector has a small opening at the top. The small opening is provided at the top of the air ejector. The small opening is provided at the centre of the flat face. The small opening is arranged perpendicular to the blind hole.
[0021] The spring is arranged in a pre compressed condition. The spring is provided below the air ejector for pushing the ejector upwardly during the upward movement of the press unit.
[0022] One end of the nozzle is fixed to a base plate in the press tool. Another end of the nozzle is fixed to an air inlet. The nozzle has a hole. The hole in the nozzle is connected to the blind hole in the air ejector through the passages and holes that are provided in the base plate. .
[0023] According to one embodiment of the present invention, the ejector unit is assembled in the die plate. The ejector with an outside body profile is well guided in the hole in the die plate. The hole in the die plate is made in such a way that the orientation of the ejector in the assembled condition is made in the required manner and the hole / opening for the air from the ejector is arranged in the required direction only.
[0024] A spring is placed below the ejector. This spring pushes the ejector upward. The collar on the ejector butts against the die bottom surface and the upward movement is restricted. The hole / opening for the air in the ejector is positioned

above the die surface in that condition. The hole in the ejector is connected to the air nozzle mounted on the base plate through the passages and holes in the die plate, backing plate and base plate. Compressed air is supplied to the ejector through the nozzle.
[0025] During the downward stroke of the press, the stripper touches the top of the ejector and pushes it down into the hole in the die plate. This movement is compensated by the compression of the spring. The hole / opening in the ejector moves inside the hole of the die plate and the air supply gets blocked during that time. The component which is parted out from the strip / coil, still remains on the die surface after the downward stroke of the press unit.
[0026] During the upward stroke of the press, the ejector moves up with the stripper plate with the support of the compression spring. Thus the opening / hole in the ejector comes above the top portion of the die surface and compressed air is passed out. Due to the orientation of the ejector in the die plate, the forced air directly falls on the component resting on the die surface thereby blowing out / ejecting out of the component from the tool before the start of the next stroke-
E) BRIEF DESCRIPTION OF THE DRAWINGS
[0027] 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:
[0028] FIG.l illustrates the sectional view of a typical press tool assembly provided with an air ejection mechanism, according to one embodiment of the present invention.

[0029] FIG.2 illustrates the top plan view of strip layout indicating the component and parting off region and enlarged view of the component in a press tool assembly provided with an air ejection mechanism according to one embodiment of the present invention.
[0030] FIG.3iIlustrates the partial sectional view of a press tool with an air ejector mechanism during the downward stroke of the press unit according to one embodiment of the present invention.
[0031] FIG.4 illustrates the partial sectional view of a press tool with an air ejector mechanism during the upward stroke of the press unit according to one embodiment of the present invention.
[0032] FIG.5 illustrates the sectional view of the ejectors indicating the flat face and blind holes according to one embodiment of the present invention. [0033] FIG.6illustrates the top side plan view of a die plate indicating a parting die and hole of ejectors in a press tool with an air ejector mechanism according to one embodiment of the present invention.
[0034] FIG.7 illustrates the enlarged plan view of the die plate indicating the flat face on the holes for ejectors in a press tool with an air ejector mechanism according to one embodiment of the present invention.
[0035] FIG.8 illustrates the enlarged top side plan view of a fixed half of a press tool assembly provided with an air ejection mechanism according to one embodiment of the present invention.

[0036] FIG.9 illustrates the enlarged top side plan view of a fixed half of a press tool assembly provided with an air ejection mechanism according to one embodiment of the present invention.
[0037] Although the 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
[0038] 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.
[0039] The various embodiments of the present invention provide a system and method for ejecting of components from the press tool. According to one embodiment of the present invention, an air ejector mechanism for press tools has an air ejector unit provided in a die plate in a press tool. A spring is arranged below the air ejector unit. A nozzle is connected to the air ejector unit. The air ejector unit is projected outside the die plate by the spring during the upward movement of a press unit to discharge air to eject a component from the press tool.

[0040] The air ejector unit is arranged inside a hole in the die plate. The air ejector unit is moved inside the die hole in the die plate during the downward movement of the press unit to block the supply of air from the air ejector unit.
[0041] The air ejector unit has an elongated air ejector. The elongated air ejector is a cylindrical element. The air ejector has a step at the bottom to receive the spring. The step is provided to act as a stopper for upward movement. The air ejector has a blind hole at the centre. The blind hole is extended from the bottom side of the air ejector. The air ejector has a flat surface at one face. The air ejector has a small opening at the top. The small opening is provided at the top of the air ejector. The small opening is provided at the centre of the flat face. The small opening is arranged perpendicular to the blind hole.
[0042] The spring is arranged in a pre compressed condition. The spring is provided below the air ejector for pushing the ejector upwardly during the upward movement of the press unit.
[0043] One end of the nozzle is fixed to a base plate in the press tool. Another end of the nozzle is fixed to an air inlet. The nozzle has a hole. The hole in the nozzle is connected to the blind hole in the air ejector through the passages and holes that are provided in the base plate.
[0044] According to one embodiment of the present invention, the air ejectors are provided in a die hole arranged in a die plate in a press tool. A spring is arranged below the air ejector in a pre compressed condition. A nozzle connected to an air inlet is connected to the air ejector through the passages provided in a base plate in a press tool to supply air to the air ejector. The air is blown from the air ejectors to remove the component from the press tool.

[0045] The ejectors are cylindrical in shape and have a step / collar at the bottom. Normally the height of the ejector is set more than the thickness of the die plate. A blind hole is provided at the centre of the ejector from the bottom side. The depth of the hole is decided depending on the thickness of the die plate. One face of the ejector is made flat. A small hole / opening is provided at the top of the ejector. This hole is arranged perpendicular to the blind hole and is provided at the centre of the flat face of the ejector. The ejector is projected out of the die block, when the tool is in the upward stroke condition. The opening in the ejector is positioned above the die surface at that time (during the upward stroke condition of the press unit).
[0046] Air is supplied inside the tool through the bottom half (i.e. through base plate and backing plate) from a standard air nozzle. This is connected to the ejector with the holes provided in the base plate and backing plate. The nozzle is connected to a compressor or any other compressed air supply mechanism.
[0047] The ejector is precisely guided in the die plate. The collar / step provided at the bottom face butts against the bottom surface of the die plate and acts as a stopper for an upward movement. The guiding hole in the die plate is of the same shape as that of the ejector. The flat face on the ejector is also precisely guided and the desired orientation of the ejector on the assembly is achieved. A spring is provided below the ejector to make the ejector a floating member. The spring is housed in the hole on the die back plate or in the base plate of the tool. The spring constantly pushes the ejector upwardly in the pre compressed condition.
[0048] During the downward stroke of the press unit, the ejector is pushed
down into the die plate by the stripper plate. The spring gets compressed and the opening / hole in the ejector is pushed inside the die plate. This blocks the air supply. The component is parted out by the punch. The finished component remains on the surface of the die plate. This component is not disturbed by air at this time, since

positive blocking of air supply is done. The component which is parted out from the strip / coil remains on the die surface after the press downward stroke.
[0049] During the upward stroke of the press, the ejector moves up with the stripper plate with the support of compression spring. Thus the opening / hole in the ejector is positioned above the top portion of the die surface and the compressed air is passed out. Due to the orientation of the ejector in the die plate, the forced air directly falls on the component resting on the die surface thereby blowing out / ejecting out of the component from the tool before the start of the next stroke.
[0050] FIG.l illustrates the sectional view of a typical press tool assembly provided with an air ejection mechanism, according to one embodiment of the present invention. With respect to FIG.l, the press tool assembly mainly consists of two halves, namely fixed bottom half and moving top half. The fixed bottom half is secured to the stationary bolster plate of a mechanical press. It comprises of an arrangement to guide the strip/coil, die cavities, guide pillars for alignment of both halves etc. The top moving half is clamped to the moving ram of the mechanical press and it comprises a number of circular and non circular cutting and non cutting elements called punches 8. The base plate 2 is clamped to the fixed bottom part. The die plate 3 is clamped on the base plate 2 with the strip or coil to be punched is guided on the die plate 3. The stripper plate 5 is clamped to the die plate 3. The top plate 1 is clamped to the moving top half. The holder plate 6 is clamped to the top plate 1. The holder plate 6 holds the punches 8. The punches 8 move up and down along with the moving ram of the mechanical press and they are guided in cavities made in a plate called stripper plate 5. During downward movement, the punches 8 penetrate the sheet metal and enter the die cavity thus pushing the sheet metal scrap displaced by the cutting punch 8 into the lower half of the tool. The surrounding metal clings to the body of cutting punches 8 during downward stroke. The same is stripped off by the stripper plate 5 during upward stroke of the punches 8.

[0051] Press tool may be of multi-station type (progressive) or single station type. In a multi-station tool, the strip moves from one end of strip guides to the other end. It moves progressively by a fixed distance called pitch after every stroke of the mechanical press. At each stage of movement of strip, different punching operations are carried out on strip / coil leading to completion of stamping profile in last stage.
[0052] The strip / coil is punched, formed, bend and made to different shaped
inside the tool. Finally the component is blanked out or parted out from the strip / coil. After blanking the finished component is pushed out of the tool through the cavity in the die and bottom plate. This component is collected from the bottom side of the press tool. The parted out component remains on the top of the die cavity and is taken out of the tool from the sides or in the direction of feeding by supply of air.
[0053] The component is a separate element, free from the strip / coil after the
parting operation. This remains on the top of the die plate 3 after parting operation. This is to be removed from the press tool before the next stroke of press or else the component which remains on the die and will get damaged and damage the tool elements and strip in the next stroke. So the components are to be ejected / removed out of the tool before the next stroke takes place. This is achieved by supply of forced air.
[0054] The air ejectors are provided at convenient places in the die. Air pressure
and direction of air supply is effective on the component and it is ensured that no hindrances / obstacles are in the passage of the component removal. The ejector is made in such a way that the air is always supplied in the required direction at required time and is placed in the tool in the required orientation only. Continuous supply of air will cause problems for feeding and may displace the component anywhere in the tool during working, since punches and other tooling elements becomes an obstacle for the smooth air flow in the downward stroke. So air supply is stopped during the downward stroke.

[0055] During the downward stroke of the press unit, the ejector is pushed
down into the die plate 3 by the stripper plate 5. The spring gets compressed and the opening / hole in the ejector is pushed inside the die plate 3. This blocks the air supply. The component is parted out by the punch 8. The finished component remains on the surface of the die plate 3. This component is not disturbed by air at this time, since positive blocking of air supply is done. The component which is parted out from the strip / coil remains on the die surface after the press downward stroke.
[0056] During the upward stroke of the press, the ejector moves up with the stripper plate 5 with the support of compression spring. Thus the opening / hole in the ejector is positioned above the top portion of the die surface and the compressed air is passed out. Due to the orientation of the ejector in the die plate 5, the forced air directly falls on the component resting on the die surface thereby blowing out / ejecting out of the component from the tool before the start of the next stroke.
[0057] F1G.2 illustrates the top plan view of strip layout indicating the component and parting off region and enlarged view of the component in a press tool assembly provided with an air ejection mechanism according to one embodiment of the present invention. With respect to FIG.2, the strip layout has a component 9 and the parting off region 7. The strip / coil 4 is punched, formed, bend and made to different shaped inside the tool. Finally the component 9 is blanked out or parted out from the strip / coil 4. After blanking the finished component 9 is pushed out of the tool through the cavity in the die and bottom plate. This component 9 is collected from the bottom side of the press tool. The parted out component 9 remains on the top of the die plate 3 after parting operation. This is to be removed from the press tool before the next stroke of press or else the component 9 which remains on the die and will get damaged and damage the tool elements and strip in the next stroke. So the

components 9 are to be ejected / removed out of the tool before the next stroke takes place.
[0058] FIG.3 illustrates the partial sectional view of a press tool with an air ejector mechanism during the downward stroke of the press unit according to one embodiment of the present invention. With respect to FIG.3, the air ejectors 12 are provided in a die hole arranged in a die plate 3 in a press tool. A spring 14 is arranged below the air ejector 12 in a pre compressed condition. A nozzle 10 connected to an air inlet 11 is connected to the air ejector 12 through the passages provided in a base plate 2 in a press tool to supply air to the air ejector 12. The air is blown from the air ejectors 12 to remove the component from the press tool.
[0059] During the downward stroke of the press, the ejector 12 is pushed down into the die plate 3 by the stripper plate 5. The spring 14 gets compressed and the opening / hole in the ejector 12 are pushed inside the die plate 3. This blocks the air supply. The component is parted out by the punch. The finished component remains on the surface of the die plate. This component is not disturbed by air at this time, since positive blocking of air supply is done.
[0060] FIG.4 illustrates the partial sectional view of a press tool with an air ejector mechanism during the upward stroke of the press unit according to one embodiment of the present invention. With respect FIG.4, the air ejectors 12 are provided in a die hole arranged in a die plate 3 in a press tool. A spring 14 is arranged below the air ejector 12 in a pre compressed condition. A nozzle 10 connected to an air inlet 11 is connected to the air ejector 12 through the passages provided in a base plate 2 in a press tool to supply air to the air ejector 12. The air is blown from the air ejectors 12 to remove the component 9 from the press tool.

[0061] During the upward stroke of the press, the ejector 12 moves up with the stripper plate 5 with the support of the compression spring 14. Thus the opening / hole in the ejector 12 is positioned above the top of the die surface and compressed air is passed out. Due to the orientation of the ejector 12 in the die plate 3, the forced air directly falls on the component 9 resting on the die surface thereby blowing out / ejecting out a component from the tool before the start of the next stroke.
[0062] During the upward stroke of the press unit, the spring 14 placed below the ejector 12 pushes the ejector 12 upward. The collar on the ejector butts against the die bottom surface and the upward movement is restricted. The hole / opening for the air in the ejector 12 is positioned above the die surface in that condition. The hole in the ejector 12 is connected to the air nozzle 10 mounted on the base plate 2 through the passages and holes in the die plate 3, backing plate 13 and base plate 2. Compressed air is supplied to the ejector 12 through the nozzle 10. The air supplied to the ejector 12 is passed through the hole to eject a component 9 from the tool.
[0063] FIG.5 illustrates the sectional view of the ejectors indicating the flat face and blind holes according to one embodiment of the present invention. With respect to FIG.5, The air ejector unit 12 has an elongated air ejector. The elongated air ejector 12 is a cylindrical element. The air ejector 12 has a step at the bottom to receive the spring. The step is provided to act as a stopper for upward movement. The air ejector 12 has a blind hole 16 at the centre. The blind hole 16 is extended from the bottom side of the air ejector 12. The air ejector 12 has a flat surface 15 at one face. The air ejector 12 has a small opening 17 at the top. The small opening 17 is provided at the top of the air ejector 12. The small opening 17 is provided at the centre of the flat face 15. The small opening 17 is arranged perpendicular to the blind hole 16.
[0064] Normally the height of the ejector 12 is arranged more than the die plate thickness. A blind hole 16 is provided at the centre of the ejector from the bottom

side. The depth of the hole 16 is decided depending on the die plate 3 thicknesses. One face 15 of the ejector 12 is made flat. A small hole / opening 17 are provided at the top of the ejector 12. This hole 17 is perpendicular to the blind hole 16 and is made from the centre of the flat face 15 of ejector. The ejector 12 projects out of the die block when the tool is in the upward stroke condition. The opening 17 in the ejector is positioned above the die surface during the upward stroke of the press to blow air towards the component resting on the die surface to eject the component from the tool.
[0065] FIG.6 illustrates the top side plan view of a die plate indicating a parting die and hole of ejectors in a press tool with an air ejector mechanism according to one embodiment of the present invention. With respect to FIG.6, the die plate 3 is provided with a parting die 7 and holes for the ejectors 12. The ejector 12 is assembled in the die plate 3. The outside body profile of the ejector is well guided in the hole in the die plate 3.
[0066] FIG.7 illustrates the enlarged plan view of the die plate indicating the flat face on the holes for ejectors in a press tool with an air ejector mechanism according to one embodiment of the present invention. With respect to FIG.7, the die plate 3 is provided with a hole to receive the ejectors 12 having a hole with a flat face 15. The hole in the die plate is designed in such a way that the orientation of the ejector 12 in the assembled condition is in the required manner and the hole / opening for the air from the ejector 12 is oriented in the required direction only.
[0067] FIG.8 illustrates the enlarged top side plan view of a fixed half of a press tool assembly provided with an air ejection mechanism according to one embodiment of the present invention. With respect to FIG.8, the air ejectors 12 are provided at convenient places in the die to eject air to blow out the components from the press tool. Air pressure and direction of air supply is effective on the component and it is

ensured that no hindrances / obstacles are in the passage of the component removal. The ejector 12 is made in such a way that the air is always supplied in the required direction at required time and is placed in the tool in the required orientation only.
[0068] A nozzle 10 is connected to the air ejector unit 12. One end of the nozzle 10 is fixed to a base plate in the press tool. Another end of the nozzle 10 is fixed to an air inlet 11. The nozzle has a hole. The hole in the nozzle is connected to a blind hole in the air ejector through the passages and holes that are provided in the base plate. The nozzle 10 is connected to a compressor or any other compressed air supply mechanism.
[0069] The ejector 12 is made in such a way that the air is always supplied in the required direction at required time and is placed in the tool in the required orientation only. When the press is moved up, the ejectors 12 are positioned above the top surface of the die plate to blow out air to eject the component from the press tool.
[0070] Continuous supply of air will cause problems for feeding and may displace the component 9 anywhere in the tool during working, since punches 8 and other tooling elements becomes an obstacle for the smooth air flow in the downward stroke. So air supply is stopped during the downward stroke.
[0071] FIG.9 illustrates the enlarged top side plan view of a fixed half of a press tool assembly provided with an air ejection mechanism according to one embodiment of the present invention. With respect to FIG.9, air is supplied inside the tool through the base plate and backing plate provided in the bottom half from a standard air nozzle 10. The air nozzle 10 is connected to the ejector 12 with the holes provided in the base plate and backing plate. The nozzle 10 is connected to a compressor or any other compressed air supply mechanism.

[0072] Air pressure and direction of air supply is effective on the component 9 and it is ensured that no hindrances / obstacles are in the passage of the component 9 removal. The ejector 12 is made in such a way that the air is always supplied in the required direction at required time and is placed in the tool in the required orientation only.
[0073] Continuous supply of air will cause problems for feeding and may displace the component 9 anywhere in the tool during working, since punches and other tooling elements becomes an obstacle for the smooth air flow in the downward stroke. So air supply is stopped during the downward stroke.
[0074] During the downward stroke of the press unit, the ejector 12 is pushed
down into the die plate by the stripper plate. The spring gets compressed and the opening / hole in the ejector is pushed inside the die plate. This blocks the air supply. The component 9 is parted out by the punch. The finished component remains on the surface of the die plate. This component 9 is not disturbed by air at this time, since positive blocking of air supply is done. The component which is parted out from the strip / coil remains on the die surface after the press downward stroke.
[0075] During the upward stroke of the press, the ejector 12 moves up with the stripper plate with the support of compression spring. Thus the opening / hole in the ejector is positioned above the top portion of the die surface and the compressed air is passed out. Due to the orientation of the ejector 12 in the die plate, the forced air directly falls on the component resting on the die cavity 7 in the die surface thereby blowing out / ejecting out of the component from the tool before the start of the next stroke.
[0076] Air is supplied inside the tool through the base plate and backing plate provided in the bottom half from a standard air nozzle 10. This is connected to the ejector 12 with the holes provided in the base plate and backing plate. The nozzle 10

has an air inlet 11 which is connected to a compressor or any other compressed air supply mechanism.
[0077] The ejector 12 is precisely guided in the die plate. The collar / step provided at the bottom face butts against the die plate bottom surface and acts as a stopper for upward movement. The guiding hole in the die plate is of the same shape as that of the ejector 12. The flat face on the ejector 12 is also precisely guided and orientation of the ejector 12 on assembly is achieved. A spring is provided below the ejector 12 to make the ejector 12 as a floating member. The spring is housed in the hole on the die back plate or in the base plate of the tool. The spring constantly pushes the ejector 12 upward in the pre compressed condition.
G) ADVANTAGES OF THE INVENTION
[0078] Thus the various embodiments of the present invention provide a method and arrangement for ejecting components from press tools positively after every stroke by applying pressurized air through the ejectors. The ejection of components from press tools is allowed only during upward stroke and blocked during downward stroke thereby preventing damages to the tool elements and components. Air pressure is adjusted according to the weight of the component, which makes the mechanism flexible in press tool applications. The cost of the mechanism is reduced since air is only used for ejecting the components. The assembly and the maintenance of the system are simplified.
[0079] 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.
[0080] 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: October 26, 2009 Place: Bangalore.

CLAIMS
What is claimed is:
1. An air ejector mechanism for press tools comprising:
At least an air ejector unit provided in a die plate in a press tool;
A spring arranged below the air ejector unit;
A nozzle connected to the air ejector unit;
Wherein the air ejector unit is projected outside the die plate by the spring during
the upward movement of a press unit to discharge air to eject a component from
the press tool.
2. The mechanism according to claim 1, wherein the air ejector unit is arranged inside a hole in the die plate.
3. The mechanism according to claim 1, wherein the air ejector unit is moved inside the die hole in the die plate during the downward movement of the press unit to block the supply of air from the air ejector unit.
4. The mechanism according to claim 1, wherein the air ejector unit has an elongated air ejector.
5. The mechanism according to claim I, wherein the elongated air ejector is a cylindrical element.
6. The mechanism according to claim 1, wherein the air ejector has a step at the bottom to receive the spring.
7. The mechanism according to claim 1, wherein the step is provided to act as a stopper for upward movement.

8. The mechanism according to claim 1, wherein the air ejector has a blind hole at the centre.
9. The mechanism according to claim 1, wherein the blind hole is extended from the bottom side of the air ejector.
10. The mechanism according to claim 1, wherein the air ejector has a flat surface at one face.

11. The mechanism according to claim 1, wherein the air ejector has a small opening at the top.
12. The mechanism according to claim 1, wherein the small opening is provided at the top of the air ejector.
13. The mechanism according to claim 1, wherein the small opening is provided at the centre of the flat face.
14. The mechanism according to claim 1, wherein the small opening is arranged perpendicular to the blind hole.
15. The mechanism according to claim 1, wherein the spring is arranged in a pre compressed condition.
16. The mechanism according to claim 1, wherein the spring is provided below the air ejector for pushing the projector upwardly during the upward movement of the press unit.

17. The mechanism according to claim 1, wherein one end of the nozzle is fixed to a base plate in the press tool.
18. The mechanism according to claim 1, wherein another end of the nozzle is fixed
to an air inlet.
19. The mechanism according to claim 1, wherein the nozzle has a hole.
To,
The Controller of Patents, The Patent office, At Mumbai
20. The mechanism according to claim 1, wherein the hole in the nozzle is
connected to the blind hole in the air ejector through the passages and holes that
are provided in the base plate.