AU605998B2 - Apparatus for removing off cuts from a die - Google Patents

Description

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zAXMAnsl bdou|)J!q 61 ZAXMAniS80dNW1NIH 0 VId 1 '1.25. 1 IIIII H i COMMONWEALTH OF AUSTRALIA The Patents Act 1952-1969 Name of Applicant(s): Address of Applicant(s) BAILEY ALUMINIUM PRODUCTS PTY LTD 69-71 ACTIVITY STREET ACACIA RIDGE QLD 4110 G.R. CULLEN COMPANY, Patent Trade Mark Attorneys, Dalgety House, 79 Eagle Street, Brisbane, Qld. 4000, Australia.

e e* ft a e a0 *o 8 o o a ft 0 *0 6 MO S "a I Address for Service: COMPLETE SPECIFICATION FOR THE INVENTION ENTITLED: APPARATUS FOR REMOVING OFF CUTS FROM A DIE 0

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The following statement is a full description of the invention including the best rmthod of performing it known to us: B003134 01 /09/89 .VCATiON ACCEPTED AND AMENDMENTS ALLOWED 2 THIS INVENTION relates to an apparatus for removing off-cuts from a die.

Australian Patent 547250 discloses an apparatus for assembling frames and in particular ladder frames of the type having a pair of side members and a plurality of transverse members extending between the side members. The text and drawings of Australian Patent 547250 are incorporated herein by way of cross reference. The apparatus included a carriage assembly for supporting the side members and the transerse members in an operative position. The carriage assembly was adapted to advance the side members and transverse members in 0 0~ their operative position along a path. Two pairs of hydraulic rams were spaced longitudinally along t 'e path.

The hydraulic rams of each pair were disposed at opposite sides of the path and were provided with operating heads.

The operating heads of the first pair of hydraulic rams .0 included blanking dies which were inwardly movable to engage the side members and cause the opposite end portions of the 0- transverse members to be forced through the side members.

The second pair of hydraulic rams were provided with swaging dies and these dies were also inwardly movable to swage end 4 portions of the transverse members about the side members.

This apparatus allowed for easy assembly of ladder frames, cable trays and other types of similar assemblies. The end portions of the transverse members were generally tubular and the act of forcing the ends through the side members caused 3 holes to be punched through the side members and resulted in the formation of an off-cut. This process is described in Australian Patent 527 037 and the text and drawings of this patent specification are incorporated herein by way of cross reference.

In these earlier patent specifications, the ends of the transverse members function as spigots in the blanking operation and are generally slightly out of normal tolerance in size. It is also not unusual for the blanking dies to be A1 incorrectly lined up with the side members. When a blanking 0 6 or punching operation is carried out particularly when the resulting assembly is intended to form a step ladder there are added difficulties. With step ladders, the longitudinal 06 side members or stiles generally present a tapered surface which abuts against the face of the blanking die. When the dies meet the tapered stile and are held in position there is S a tendency for the stiles to slightly move due to their tapered profile causing the die to make a double hit or a a t double blanking movement. When this happens, the resulting t off-cut will have a ragged peripheral edge instead of a clean peripheral edge. This ragged peripheral edge can cause the off-cut to adhere or stick to the die face or to the transverse member.

The off-cuts resulting from the punching operation accumulate in or around the blanking dies and need to be promptly removed to prevent interference with subsequent 4 operation of the blanking die. The off-cuts were removed by providing a collection chute to the die into which the offcuts fell and were gravity fed to a collection bin.

IA disadvantage with removing off-cuts in this manner was that occasionally off-cuts adhered to the die face particularly when provided with a ragged peripheral edge or ,r adhere to the end of the transverse member. The off-cuts, J thus, did not fall into the collection chute. As the time i interval between successive die operations is relatively brief, if the off-cuts were not promptly removed from the die 0*9* or the end of the transverse member they would interfere with subsequent operation of the die. This resulted in increased maintenance or downtime of the whole assembly in which the So machine dies were cleared of off-cuts. When the off-cuts 6 1 adhered to the ends of the transverse members, the subsequent swaging operation forced the off-cuts into the transverse members and created an unacceptable product which was required to be scrapped.

The above disadvantages resulted in a reduction in overall efficiency, and wasted material and labour and resulted in increased downtime of the dies in order to clear jammed or adhering off-cuts.

It is an object of the present invention to provide an apparatus for removing off-cuts from the die which at least partially minimises the abovementioned disadvantages.

According to one aspect of the inven'tion, there is provided an apparatus for removing punched material from a die, said apparatus including a blanking die against which a first member may abut to enable a second member to punch material therefrom to form one or more holes in the first member, a chamber within said blanking die to receive the punched material from said first member, an outlet associated with said chamber to pass said punched material from said chamber and a pump for pressurising said die to facilitate removal of said punched material from said chamber and trr ,tjo through said outlet.

'r The apparatus may be used for forming ladders trte having side members or stiles and transverse members or rungs. The first member may thus comprise the stile and the j :fn second member may comprise the rung.

~In a preferred form, the rung of the ladder is I provided with a pair of projections or spigots on each end face which are punched through the web of the stile. The blanking die, thus, prefe.-ably has two apertures to facilitate punching of two openings into the web of the side member or stile. Preferably the interior of the blanking die is contoured or shaped to facilitate the movement of the punched material or off-cuts into the interior of the chamber. Preferably, two spaced dies are employed such that

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where a ladder or like assembly is being formed by the punching action, the transverse member or rungs may be simultaneously punched through both side members.

6 The apertures of the blanking die may be in direct contact with the chamber whereby a side wall of the chamber includes the apertures. Alternately, the apertures of the blanking die may be spaced from the chamber and connected thereto through passageways. The passageways may be outwardly tapered from the apertures to the chamber to allow the punched material or off-cuts to freely pass into the 6 0 chamber.

The chamber may be of any suitable size or shape to accommodate the off-cuts. The chamber may temporarily store 64 S the off-cuts before they pass through the outlet. The chamber may have an internal configuration to maximise the ease of passage of the off-cuts between the apertures and the outlet. Preferably, the chamber has a downwardly inclined 4 04 i i ~rear face and the outlet is associated with this portion of the chamber.

The pressure pump may comprise any type of pump to supply pressure to the apparatus to facilitate the passage of the punched material through said outlet. It is preferred that the pressure pump communicates pressure to the chamber of the blanking die. The pressure pump may provide positive or negative pressure to the apparatus or chamber. Thus, the pressure pump may comprise a vacuum or suction pump to supply vacuum to the chamber or may comprise a positive pressure pump to supply pressurized air or other fluid to the chamber.

The fluid provided by the pressure pump typically comprises 7 air but can also comprise any other type of fluid such as nitrogen if an inert atmosphere is required around the apparatus.

If the apparatus is in communication with a suction or vacuum pump, the outlet of the apparatus may be coupled to connect to a receptacle. The receptacle may be a bin into which the off-cuts collect. The bin preferably has a removable lid or cover. The lid preferably forms a eei e substantially fluid tight seal relative to the remainder of eq 00 e eeoo .3Q the bin. The conduit leading from the die and through which *00 the off-cuts pass preferably enters a side wall of the bin S while the conduit from the bin leading to the source of the vacuum preferably enters the bin through the lid. The conduit between the vacuum pump and the lid of the bin may be provided with a screen or other type of barrier to prevent C e C 0 to any off-cuts from accidently passing into the vacuum pump.

ice The outlet of the vacuum pump may be connected to further outlet conduit which may extend above a roof or through an exterior wall. A plurality of receptacles may be provided which are in vacuum communication with the pump and the die.

Initially, one of the plurality of receptacles may be coupled to the die through suitable conduit. When this receptacle is filled to capacity, vacuum may be diverted to a second of the plurality of receptacles which will then accommodate further off-cuts. The first receptacle can then be removed from the vacuum source and emptied without the need for any a.

8 down time for the apparatus making the step ladders or other assemblies.

If the pressure pump communicates a positive pressure to the chamber, conduit may be provided from the pump to the top of the chamber. As an off-cut enters the chamber it may be blown through the outlet by the pressurized fluid entering the top of the chamber. Alternately, the pressurized fluid can be associated with the apertures of the blanking die to facilitate the entry of the off-cuts into the 1 chamber and subsequently through the outlet.

The invention will be further understood by reference to the following description of a particular #115 preferred embodiment as illustrated in the accompanying drawings in which Figure 1 is a front end view of a typical blanking die.

Figure 2 is a section view of the die of figure 1 taken along line A-A.

Figure 3 is a view of a preferred pressure pump according to an embodiment of the invention.

The apparatus for removing punched material from a die includes a blanking die 10 having apertures 31, 32. The ends of transverse members may project through apertures 31, 32 and into passageways 11, 12 once they are punched through the side members. Passageways 11, 12 taper outwardly into a chamber 13. This provides for a smoother passage of the offcut portions and less likelihood of the off-cuts adhering around apertures 31, 32. An outlet 14 is provided from chamber 13 and leads to a conduit or duct 15. The hydraulic ram which moves the die to cause the transverse member to be punched through the side member is not shown. Where the transverse member is a step of a ladder and the side member is a ladder stile, two transversely spaced dies 10 are employed.

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S a r .rChamber 13 is provided with a downwardly inclined R0o rear wall 16 the base of which is associated with outlet 14.

0 Q The die is in communication with a vacuum source and a Qar S preferred form is shown in figure 3. Figure 3 shows a pressure pump assembly having a vacuum pump 26. The assembly has a receptacle 21 from which extends a conduit 22. One end 0'1. of conduit 22 communicates with the interior of the So receptacle through a side wall. The other end of conduit 22 a a.

is bifurcated and terminates in two flexible conduits 23,24.

Flexible conduits are coupled to ducts 15 which extends from outlet 14. The bifurcated conduits is used for the apparatus of the patent specification 547 250 which discloses two opposed dies.

Receptacle 21 is in vacuum communication through conduit 25 to a source of vacuum provided by a fan, blower or vapour pump 26. An outlet for the blower 26 may be provided a short distance away by outlet conduit 27. Alternately, the outlet may be provided by a long outlet conduit 28 extending above a roof The blower provides a relatively high vacuum, typically about 300 bar or greater and an air flow of about 4.6m/min is provided to aid in the transportation of off-cuts from chamber 13 to receptacle 21. A filter or other barrier is located in conduit 25 to ensure that off-cuts are not drawn into blower 26. Typically, the velocity of extraction of off-cuts is about 26 metres/second.

The conduits may be made of any suitable material such as plastics or metal. Preferably galvanized iron is employed for all the conduits except for flexible conduits 23 t t S and 24.

rt During use, receptacle 21 is periodically emptied.

ilt The arrangement of the invention enables off-cuts to be removed from the die under the influence of vacuum. Air can be drawn into the die through apertures 31, 32 once die 10 is withdrawn after the punching operation. Where a ladder is being made, two spaced dies 10 are employed and a respective conduit communicates with each die.

The use of the vacuum to remove off-cuts also aids in the punching operation. The vacuum facilitates the holding of the styles firmly in position against a blanking die and minimizes movement of the style during punching.

This results in a cleaner shear of the off-cuts during blanking. The vacuum then draws the off-cut through passageways 11, 12 chamber 13, outlet 14 and through the i 11 vacuum conduit into receptacle 21. Because the stile is firmly held in position by the vacuum the off-cut has a smoother peripheral edge and is less likely to damage the vacuum conduit or to adhere to the die face.

It should be appreciated that various other changes and modifications may be made to the embodiment described without departing from the spirit'and scope of the invention as defined in the accompanying claims.

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Claims (19)

1. An apparatus for removing punched material from a die, said apparatus including a blanking die against which a first member may abut to enable a second member to punch material therefrom to form one or more holes in said first member, a chamber within said blanking die to receive the punched material from said member, an outlet associated with said chamber and a pump for pressurising said die to facilitate removal of said punched material from said chamber of and through said outlet. S I S,1

2. The apparatus as claimed in claim 1, wherein said blanking die includes a pair of apertures. ca

3. The apparatus as claimed in claim 2, wherein said chamber is spaced from said apertures and is in communication with said apertures through passageways.

4. The apparatus as claimed in claim 3, wherein the cross-sectional area of said passageways increases from the apertures to the.chamber.

The apparatus as claimed in any one of claims 1 to 4, wherein said chamber has a downwardly inclined rear wall.

6. The apparatus as claimed in claim 5, wherein said Soutlet is located adjacent the downwardly inclined rear wall of said chamber.

7. The apparatus as claimed in any one of the preceding claims, wherein said pump includes a blower, fan or vapour pump. L i i 13

8. The apparatus as claimed in claim 7, wherein said pump communicates positive pressure to said chamber.

9. The apparatus as claimed in any one of claims 1 to 7, wherein said pump communicates a vacuum to said chamber.

The apparatus as claimed in claim 9, wherein said outlet is coupled to said pump to supply a vacuum to said chamber.

11. The apparatus as claimed in claim 10, wherein a receptacle is located between said outlet and said pump to collect said punched material.

12. The apparatus as claimed in claim 11, wherein said A receptacle comprises a bin having a side wall and a S removable lid or cover. it

13. The apparatus as claimed in claim 12, wherein a first conduit extends between the side wall of the bin and S"the outlet and a second conduit extends between the removable lid or cover and the pump.

14. The apparatus as claimed in claim 13, wherein a screen is located within the second conduit to prevent punched material from entering into said pump.

The apparatus as claimed in any one of claims 9 to 14, wherein exhaust conduit is coupled to said pump.

16. The apparatus as claimed in claim 15, wherein said exhaust conduit extends through a roof or wall of a building.

17. The apparatus as claimed in any one of claims 9 to 16, wherein said pump communicates a vacuum to locate said i_ L 1 14 first member against said blanking die.

18. The apparatus as claimed in any one of claims 9 to 16, wherein said apparatus includes a pair of blanking dies and said pressure pump communicates vacuum to both said dies.

19. The apparatus as claimed in claim 18, wherein said S punched material from said pair of blanking dies is communicated to the receptacle through said first conduit. An apparatus for removing punched material from a die as substantially as hereinbefore described with reference to the accompanying drawings. DATED this first day of September 1989. BAILEY ALUMINIUM PRODUCTS PTY LTD 0 o. "By Their Patent Attorneys -L G R CULLEN CO 0. 0 4Q