IL41341A - Combination of readily removable punch and die members - Google Patents

Description

Λ ( COMBINATION OF READILY RBMOVABLB PUNCH AND DIB MEMBERS n»na piVD^ o'jnan nyaoa-i apa » a»K loiyn This invention is conoe ned with apparatus for performing fabricating operations on sheet material suoh as, for example, sheet metal panels, and with complementing punch and die members for incorporation in such apparatus. Thus* for example, the apparatus may operatively serve for the forming of knock-outs in sheet metal panels, the sheet metal panels being formed by appropriate bending into electrical enclosures such as, for example, electrical junction boxes or electrical switchboxes* Such knock-outs are conventionally provided in electrical enclosures to permit electrical wiring and the like to be disposed at the required positions through the walls of the electrical enclosures to the interiors thereof for, for example, connection to electrical terminals disposed within the enclosures, such knockouts each being in the form of a portion of a wall of the electrical enclosure which is severed from the surrounding portion of the wall except at one or more positions at which the central severed portion of the wall remains connected to the surrounding portion thereof through a connecting tab or tabs. The portion of the wall which is so sea?vered from the surrounding portion thereof is generally of circular form and may be surrounded by one or more annular portions of the walls which are each likewise servered from the surrounding portion of the wall except at one or more positions at which they are each connected to the surrounding portion of the wall through a connecting tab or tabs* In this manner, when it is desired to dispose electrical wiring or the like through a wall of an electrical en* closure at the location of one of the knock-outs formed in the wall the central severed portion of the wall together, if required, with one or more of the surrounding severed annular portions are punched out tilth insultant breaking of the appropriate connecting tab or tabs thereby to provide an opening in the wall through which the wiring or the like is then disposed. As will be appreciated, the desired dimensions of the opening to be formed in the wall determines whether only the central severed portion of the wall or whether this portion together with one or more of the surrounding severed portions are punched out* Prior to the punching out of the appropriate portion or portions of the knock-outs each of these severed portions is generally disposed in a plane which is staggered relative to the plane of the adjacent severed portion or of the surrounding portion of the wall of the enclosure, thereby to facilitate subsequent removal of the appropriate severed portion or portions, the central severed portion of the wall generally being disposed in a plane which is located Inwardly relative to the associated enclosure of the plane containing the adjacent portion of the wall or the surrounding portion of the wall* As will be appreciated, of course, the planes in which the adjacent severed portions or the appropriate severed portion and the adjacent surrounding portion of the wall, are disposed are not, prior to the removal of the appropriate severed portion or portions, spaced apart to such an extent that a gap is provided in the wall of the enclosure between these adjacent portions* It has hitherto been the practice, in the forming of such knock-outs in sheet material, and more particularly in sheet metal panels Intended to constitute electrical enclosures, for upper and lower master shoes which in operation are mounted on the upper$*nd lower platens of a press apparatus to be provided with one or more pairs of memberst one of the members of each pair thereof being a punch member and the other member of each pair thereof being a die member, with the punch and die members of each pair of members being complimentary and being so formed that during operation of the press a knock-out is formed in the sheet metal panel when the punch and die members of each pair thereof are* on relative movement of these members towards one another* brought into mating juxtaposed relationship with the sheet metal disposed between the members. In such apparatus as hitherto used it has generally been the ease that portions of the punch and die members of each pair thereof* which members may incorporate strippers for operatively urging the sheet ma erial from the punch and die members of each pair of members when these ems members are operatively moved apart by the operation of the press apparatus after the knock-out has been formed in the sheet material, are disposed within the master shoes* and generally within specially formed compartments which are provided in the master shows and which are adapted to receive* for example, the above-mentioned strippers* Thus, the master shoes are particularly formed for punch and die members which are of a particular size and which are to be located at a particular position* the sise and positioning of the punch and die members being* of course* dependent on the design of the particular electrical enclosure to be fabricated.

The result has been that such apparatus as hitherto used can economically be used only for a relatively large roduction run f an design, since* of course* the cost of fabricating the upper and lover master shoes is relatively high and it is not feasible for the punch and die members readily to be removed and re-used in a different arrangement.

It has hitherto been proposed to provide a press apparatus Incorporating one or more pairs of punch and die members which may be removed from the apparatus and re-used in different arrangements and in which, therefor e, the above-described disadvantages of the hitherto used form of apparatus is substantially overcome, attention is this connection being particularly directed to United States patent Ho. 2,350,004 which issued on May 30, 1944 to L.v\ histler at al and w ich is the most relevant prior art of which the applicant is aware. Thus, it will be noted that with particular^ referenoe to» for example, Fig. 1 of the drawing of this patent to Whistler et al there is therein disclosed apparatus including a punch-holder and a die-holder on which a punch-member and a die-member, respectively* are removably mounted by means of retainer-elements which, as is most clearly shown in Pig. 3, are secured to the punch-holder and the die-holder by means of screws. Whistler et al also disclose the use of dowel ine each of which is disposed within one of the retainer-elements and the adjacent punch-holder or die-holder.

It will be noted, however, that in the apparatus disclosed by Whistler at al it would clearly be neeessary with punch members and die members of different diameters to provide retainer-elements of corresponding different diameters, and in addition for punch members and die members of different diameters the spacing between the screws and the dowel pins would likewise be correspondingly different. Thus, it is a disadvantage of the apparatus disclosed by Wilistier at al that it is clearly not possible for punch members and die members of different dimensions to be removably mounted at the same locations on the punch-holder and the die-holder by means of the same retainer-elements and screws together with dowel pins which are located in the punch-holder and the die-holder at the same positions.

It is a further disadvantage of the apparatus disclosed by Whistler at al that the retainer-elements together with the screws and the dowel pins by means of which each punch member and die member are removably mounted on the punch-holder or the die-holder are disposed outside the peripheries of the punch member and the die member as viewed in the direction in which these punch and die members are relatively movable towards and away from one another, since it is thereby Impossible for adjacent pairs of the punch and die members to be disposed in substantially contacting relationship. It may frequently be desirable for adjacent pairs the of/punch and die members to be.disposed in substantially con-tacting relationship, and this has apparently been appreciated by Shiatier et al since they have disclosed a modified form of the apparatus which is ehown in Figs. 21 and 22 of the drawings of the patent and in which it will be noted that the adjacent pairs of punch and die members may be disposed in closer relationship although it i3 etill not possible even with this modified apparatus of Whistler at al for the adjacent pairs of punch and die members to be disposed in contacting relationship.

From one aspect, the invention consists in a kit of parts comprising at least one pair of members of which one ρ η, ο. ^ members is a complementary die member of use with said punvh member in apparatus for performing fabricating operations on sheet material said punch and die members each being self-contained and each having screw-threaded mounting means for use in removably mounting said punch or die member as a unit in the apparatus for movement of said punch and die members towards each other into mating juxtaposed relationship for performing a fabricating operation or operations on sheet material disposed therebetween and away from each other, the mounting means of said punch and die members extending in the direction in which said punch and die members are movable when removably mounted in the apparatus and being centrally disposed wholly within the respective peripheries of said punch and die members as viewed in said direction, and at least sfiB of one said members incorporating a stripper arrangement which is constituted by a stiff but resiliently deformable plastics material and which is coaxially disposed relative to said axial direction* The invention is, therefore, to be distinguished from British Patent No* 596,621 wherein a screw-threaded memb is not centrally disposed relative to the associated punch or die membert vide screw 56 disposed in an inclined opening 55· This arrangement according to that patent considerably weakens the associated punch or die member, as well as the engagement of the end of the serew at one side of the punch or die member. These disadvantages are overcome by the present invention.

The invention further consists in a kit of parts comprising at least two pairs of punch and die members such as defined hereinabove wherein the dimensions of the pp n, punch end die members of one of s aid pairs thereof are different from the dimensions of the punch and die members of another of said pairs thereof, the dimensions of the mounting means of one of the punch and die members of one of said pairs thereof being the same as the dimensions of the mounting means of one of the punch and die members of another of said apirs thereof, and the dimensions of the mounting means of the other of the punch and die members of said one of said pairs thereof being the same dimensions of the mounting means of the other of the punch and die members of said another of said pairs thereof.

From another aspect, the invention consists in apparatus for performing fabricating operations on sheet material and comprising one or more pairs of punch and die members such as defined hereinabove and removably mounted in the apparatus* From a further aapect» the invention consists in apparatus for forming of knockouts in sheet material, the apparatus comprising at least two pairs of members, one of the members of each said pair thereof being a punch member and the other member of each said pair thereof being a die member with the punch and die members of each said pair of said members being complementary, and the members of each said pair thereof being relatively movable towards and away from one another, so that the members of each said pair, on said relative movement thereof towards one mother, are brought into mating juxtaposed relationship for the forming by the complementary punch and die members, of knockouts in a sheet of formable material which in use is disposed between said members, wherein the dimensions of the punch and die members of one of said pairs thereof differ from the dimensions of the punch and die members of another of said pairs thereof* each of said punch and die members being self-contained and being as a unit removably mounted in the apparatus by a plurality of spaced mounting members which each comprise a centrally disposed screw-threaded member extending in ¾S¾i direction in which said punch or die member and the other member which together with said punch or die member constitutes one of said pairs of members are relatively movable, and in engagement in said punch or die member and in a template removably mounted in the apparatus, and an anti-rotation locking pin which is spaced from the associated screw-threaded member and which is engaged in recesses provided in said punch or die member and in the template, a locating spigot in which the acrew-threaded member is disposed being presented by said punch, or die member provided in the template, the spaoed mounting members ox^ each of said punch and die members being disposed wholly withi the periphery of said punch or die member as viewed in said direction of relative movemen , at least one of said members of each of said pairs of members incorporating a stripper arrangement which is constituted by a stiff but resiliently deforoable plastics material and which is ooaxially disposed relative to said axial direction, and the dimensions of and spacing between the mounting members by which each of said punch and die members are removably mounted in the apparatus being substantially equal* In order that the present invention may be more clearly understood and more readily carried into effect the same will now, by way of example, be more fully described with reference to the accompanying drawings in which F , 1 is a vertically seetioned view of a part of an apparatus according to a preferred embodiment of the present invention for performing fabricating operations on sheet material, the view being taken substantially on the line 1-1 of Fig,2, Fig* 2 is a plan viev of the part of the apparatus shown in Fig. 1 , this view being taken substantially on the line 2-2 in Fig* 1 with the sheet metal panel disposed within the apparatus showAbin chain-dotted lines; Fig* 3 is a plan viev substantially corresponding to Fig* 2 but showing only the sheet metal panel after the performing thereon by the apparatus of the appropriate brir eating operation} and Fig. 4 is a sectioned viev of the portion of the sheet metal panel shown in Fig* 3 substantially on the line 4-4 in Fig,3.

Referring to the drawing, and particularly to Fig* 1 thereof, 10 denotes generally each of a plurality of being a die member. The punch of the pairs 10 of members are denoted respectively by the reference numerals 11» 12 » 13 and 14» and the die members of the pairs 10 thereof are denoted respectively by the reference numerals 16, 17» 18 and 19· The punch member 12 of the appropriate pair 10 of members comprises a centrally disposed , approximately cylindrical rigid portion 21 which is di sposed within an annular rigid portion 22» the portion 21 presenting an annular shoulder 23 with which an annular flange 24 presented by the portion 22 is in abutting engagement. The portion 22 is also provided with an inner annular recess within which an annular body 25 is di sposed , and wi th an outer annular recess within which an annular body 26 is disposed.

A transverse bore 27 is provided in the portion 22» this bore 27 being in alignment wi th a slot 28 provided in the portion 21 with a locking pin 29 operatively di sposed partially within the bore 27 and partial ly within the slot 28 thereby substantially to prevent relative rotation between the portions 21 and 22.

The di e member 17 of the pair 10 of members which includes the punch menber 12 comprises a centrally disposed, approximately cylindrical rigid portion 30 which is disposed wi thin an annular rigid portion 31, the portion 30 presenting an annular shoulder 32 wi th which an annular flange 33 presented by the portion 31 s in abutting engagement. The portion 30 is provided wi th a centrally disposed recess within which a body 34 which is secured to the portion 30 by means of a screw- threaded member 35 is located , the portion 30 also being provided wi th an annular recess within which an annular As shown in Fig. 1, the dimensions of the portion 21 of the ptinch member 12 are such that this portion 21 is a close sliding fit within the recess in the portion 30 of the die member 17 within which the body 34 is disposed, the dimensions of the annular part of the portion 22 of the punch member 12 between the recesses in which the bodies 25 and 26 are disposed likewise being such that this annular part of the portion 22 is a close sliding fit within the recess in the portion 30 of the die member 17 within which the body 36 is disposed. Thus, since the bodies 25, 26» 34 and 36 are each constituted by a stiff, but resiliently deformable plastics material such as* for example* polyurethane, the portion 21 together with the above-mentioned annular part of the portion 22 of the punch member 12 may, with resultant resilient deformation of the bodies 25, 26, 34 and 36, o era-tively enter into the appropriate recesses in the portion 30 of the die member 17 as shown in Fig. 1, when the punch and die members 12 and 17 are relatively moved towards one ai other so that the punch and die members 12 and 17 are therefore complementary. Such relative movement of the punch and die members 12 and 17 towards one another results in sheet material 37 which has been disposed between the punch and die members 12 and 17 being formed with three concentric lines of severance 38 which are more clearly shown in Figs. 3 and 4 and the outer two of which are each continuous except at two diametrically opposed locations at which the adjacent portions of the sheet material 37 separated by the lines of severence 38 remain interconnected through connecting tabs 39. The Inner line of severence 38 is continuous except at a single location at whloh the adjacent portions of the sheet material With particular reference to Fig. 1» these connecting tabs 39 result from the provision of notches 40 in the portion 21 and the above-mentioned annular part of the portion 22 of the punch member 12 and in the portion 31 of the die member 17, Thus, the pair 10 of members comprising the punch member 12 and the die member 17 operatlvely perform on the sheet material 37» which may be a sheet metal panel, a fabricating operation which results in the formation of a lnoclc-out which is in fact in the form of a tripple knockout in that it comprises three concentric lines of severence 38.

The punch and die members 11 and 16» respectively, are substantially identical to the punch and die members 12 and 17, respectively, except that, as will be noted from the drawings, the diameters of the various elements of the punch and die members 11 md 16 are somewhat less than the diameters of the corresponding elements of the punch and die members 12 and 17 wi h the result that, as shown in Figs. 3 and ^ the diameters of the three lines of severance 38 which are operatively formed in the sheet material 37 by the pair 10 of members comprising the punch member 11 and the die member 16 are somewhat less than the diameters of the three lines of severance 38 operatively formed in the sheet material 37 by the pairs 10 of members comprising the punch member 12 and the die member 17. For conveni nce, the same reference numerals have been used in the drawing to denote the appropriate elements of the punch member 11 and the die member 16 as have been used to denote the corresponding elements of the punch member 12 and the die member 17, respectively.

Y/ith reference to the pair 10 of members comprising the punch member 13 and the die member 18, it will be noted from Fig, 1 that except as noted hereinafter the punch member 13 is substantially identical to the die member 17, and except as noted hereinafter the die member 18 is substantially iden-tical to the punch member 12, F6r convenience therefore the same reference numerals have been used to denote the various elements of the punch member 13 and the die member 18 as have been used to denote the corresponding elements of the die member 17 and the punch member 12» respectively.

The punch member 13 differs from the die member 17 in ths?t in the punch member 13 there is no element corresponding to the portion 31 of the die member 17, so that of course the portion 30 of†the punch member 13 does not present an annular shoulder 3 * The die member 18 differs from the punch member 12 in that the portion 22 of the die member 18 is not provided with an annular recess w thin which an annular body 26 is disposed, and in that the recess within which the annular body 25 is disposed is provided in the portion 21 of the die member 18 rather than in the portion 22 thereof* Thus, the pair 10 of members comprising the punch memher^ 13 and the die member 18 operatively forms in the sheet material 37 a knock-out which is in the form of a double knock-out in that it compriees merely two concentric lines of severence 38, as is shown particularly in Figs. 3 and 4 of the drawings. Particularly from Fig, 3 it will also be noted that in the knock-out operatively formed by the punch and die members 13 and 18 the adjacent portions of the sheet material 37 which are separated by each of the lines of severence 38 re The punch member 14 of the appropriate pair 10 of members comprises an approximately cylindrical rigid portion 74 on the lower end of which is operatively mounted body 41 of stiff but reailiently deformable plastics material such as, for example, polyurethane» a punch pin 42 being mounted through a bore provided in the body 41 and within an elongated reoees provided in the portion 74. The upper end portion of the pin 42 is provided with an annular groove 43 within which is disposed the inner end of a screw-threaded member 44 which is screw-threadedly mounted within a transverse bore provided in the portion 74 of the punch member 14, The member 44 thus serves substantially to prevent inadvertent removel of the pin 42 from the punch mem er 14.

The die member 19 with which the punch member 14 Is associated comprises an ap roximately cylindrical, rigid portion 45 which is provided with a passage 46 within which the lower end portion of the punch pin 42 may enier as a close* sliding fit so that the punch and die members 14 and 19 are thus complementary, the passage 46 communicating w th an inclined discharge opening 47 through which a portion of the sheet material 37, which is operatively severed from the remainder of the sheet material 37 as the lower end portion of the punch pin 42 enters the passage 46 on relative movement of the punch member 14 and the die member 19. towards one another is discharged from the die member 19» With particular reference to Pig. 2, the reference numeral 53 denotes each of a plurality of punch members of pairs of punch and die members for tftorming triple knock-outs, the punch member 53 being substantially identical to one another and to the punch member 12 as ^hereinbefore described with particular reference to Fig. 1» except that as required the dimensions of the various elements of these punch members 55 may differ from one another and from the dimensions of the corresponding elements of the punch member 12. The same reference numerals have been used to denote the appropriate elements of each of these punch members 53 as have been used to denote the corresponding elements of the punch member 12» Likewise, in Fig* 2 the reference numeral 54 denotes each of a plurality, of die members of pairs of punch and die members for forming double knock-outs* the die members 54 each being substantially identiaal to one another and to the die member 18 hereinbefo e described with particular reference to Fig. 1· The appropriate elements of these die members 54 are again denoted by the same reference numerals as have been used to de* note the corresponding elements of the die member 18. The refe ence numeral 55 denotes eaoh of a plurality of die members of pairs of punch and die members for formin knock-outs each of which is in the form of a single knock-out in that it comprises a single line of severance 58 in the sheet material 37. Although such pair of punch and die mem ers for forming a single knock-out is not specifically shown in Fig. 1 it will, of course, be appreciated that in such a pair ©f punch and die members the punch member could substantially correspond to the punch member 13 with the omission of the body 36 and the die member could substantially correspond to the die member 18 with the omission of the portion 22, The reference numeral 56 denote each of a plurality of die members of pairs of punch and die members* the die members 56 being substantially identical to one another and to the die member 19* except that as requiresl the dimensions of the various elements of each of the die members 56 may differ from one another and from the dimensions of the corresponding elements of the die member 19. The appropriate elements of the die members 56 have been denoted by the same reference numerals as the corresponding elements of the die member 19.

With particular reference again to.Big. 1, the various pairs 10 of punch and die members are adapted to be removably mounted in apparatus, such as a press apparatus, for per-forming fabricating operations on sheet material, the apparatus incorporatin an upper platen 57 and a lower platen 58. These platens 57 and 58» only portions of which are shown in Fig. 1, are operatively relatively urg4d towards and amy from one another by power means such as, for example, mechanical power means (not shown) as is conventional in a press apparatus* Mounted on the lower face of the upper platen 57 by appropriate mounting means (not shown! is an upper master show 59, and mounted on the upper face of the lower platen 58 by appropriate mounting means (not shown) is a lower master show 60, An upper template 61 is mounted on the lower face of the upper master shoe 59 and a lower template 62 is mounted on the upper face of the lower master shoe 60, these templates 61 and 62 being each so mounted by means of a clamping bar arrangement which comprises a plurality of clamping bars including the clamping bar 63 shown in Fig» 1. She clamping bars 63 are each of substantially L-shape in cross section and comprise a first limb which overlies the appropriate template 61 or 62 and a second limb which is,mounted on the appropriate master shoe 5 or 60 and which is operatively rigidly t secured thereto by a plurality of spaced, screw- threaded bolts 64, a plurality of a c ew- hreaded locating members constituted by screw- threaded bolts 65 being disposed through the template 61 or 62 and being screw- thread edly engaged with the appropriate m ster shoe 59 or 60 thereby accurately to position the appropriate template 61 or 62 on the master shoe 59 or 60, respectively* prior to the clamping of . the template 61 or 62 to the master shoe 59 or 60, respectively, by means of the clamping bar arrangements com-prising the clamping bars 63.

Operative movement of the platens 5? and 58 relatively towards one another, with the pairs 10 of punch and die members removably mounted in|the apparatus results in said members of each pair 10 thereof being brought into mating Juxtaposed relationship to that with the sheet material 37 such as,, for example, a sheet metal panel disposed between the punch and die members of each pair 10 thereof a fabricating operation is p& rformed thereon, this operation in the case of, for example, the pairs 10 of members comprising the punch members 11, 12 and 13 and the die members 16, 17 and 18 resulting in the forming of knock-outs in the sheet material, and in the dase of, for example, the pair 10 of mem ers comprising the punch member 14 and the die member 19 resulting in a hole denoted by the reference numeral 71 in Figs, 3 and 4 being formed in the sheet material 37# During these fabricating operations the bodies 25, 26, 34, 36 and 41 of, for example, p&lyurethane are of course resiliently deformed so that during the subsequent movement of the platens 57 and 58 relatively away from one another the resilient stressing in these bodies 25, 26» 35, 36 and 41 is relieved with resulting urging of the sheet material 37 from the appropriate punch and die members of these pairs 10 of mem ers. These bodies 25 26, 34, 36 and 41 thus serve as stripper arrangements.

Each of the punch members 11, 12, 13 and 14 and each of the die members 16, 17, 18 and 19 is removably mounted in the apparatus by screw-threaded mounting means, comprising a screw-th eaded recess in the punch or die member, mounting means comprising a correspondingly screw-threaded member in the form of a screw-threaded bolt 66 being pr ovided for engagement with each said recess. Screw-threaded engagement of each bolt 66 with the associated recees in the punch or die member removably mounts the punch or die member in the apparatus by securing it to the appropriate template 61 or 62 through which the bolts 66 are disposed. Each bolt 66 and its associated recess is centrally disposed with respect to the associated punch or die member, ach bolt 66 is disposed through a locating spigot 67 which is presented by the appropriate punch or die member and which is operatively disposed within a complementary recees provided in the apparatus and more particularly in the appropriate template 61 or 62.

With particular reference to the punch members 11, 12, 13 and 14 and the die members 16, 17, 18 and 19 it will be noted that the screw-threaded bolts 66 and associated recesses are each disposed wholly within the periphery of the appropriate punch or die member, as viewed in the direction in which this member and the other member which together with said member constitute a pair 10 of the members are relatively movable. Thus, in this manner, it is possible for adja- close relationship* or even to be di sposed in contacting relationship, as shown in, for example, Pig. 1 in which the pair 10 of members comprising the punch member 11 and the di e member 16 are disposed in contacting relationship i th the pair 10 of members comprisi ng the punch member IS and the die member 17.

It is to be emphasized that there need be only one* al though there are preferably at least two, pairs 10 of punch and die members, and the sc ew- threaded mounting means by which the member is operatively removably mounted in the apparatus is disposed wholly within the periphery of the member as vi ewed in the above-mentioned direction, since even in an apparatus incorporating a plurality of pairs of punch and die members only one of which pairs of members has such mounting means , it will of course still be possible for this one pair 10 of members to be disposed more closely to the adjacent pair of i-imbh and die members than would otherwise be the case. It will be noted that in each of the pairs 10 of punch and di e members the punch mem er and the die member is self-contained in that it may readily be removed as a unit from the apparatus and subsequently, when required, replaced as a unit in the apparatus, al though, of course, if any damage is sustained by an individual element or elements in one of the punch or die members the member can be dismantled, the damaged element replaced and t e member reassembled so that it is not necessary to discard the entire punch or die member in which the damaged element is incorporated.

With particular reference to the paire 10 of membe s comprising the punch members 11, 12, 15 and 14 and the di e members 16, 17, 18 and 19, the dimensions of the members of mounting the members of these pairs 10 of members in the apparatus are the same, so that, as required* the positions at which these pairs 10 of members are removably mounted in the apparatus may be altered by, for example, removing the pair 10 of members comprising the punch member 12 and the die member 17 and removing the pair 10 of members comprising the punch member 13 and the die member 18 and re-mounting these pairs 10 of members in the apparatus with the pair 10 of members comprising the punch member 13 and the die member 18 mounted at the position in which the pair 10 of members comprising the punch member 12 and the die member 17 are shown in Sig. 1» and with the pair 10 of members comprising the punch member 12 and the d e member 17 mounted at the position in which the pair 10 of members comprising the punch member 13 and the die member 18 are shown in Fig. 1· In this manner, the various pairs 10 of members may, as required, be removed and either these pairs 10 of members may then be remounted in the apparatus at different positions or other pai≤3 10 of members may be mounted in the apparatus in order to provide a different arrangement* It is to be emphasized that there may be at least two pairs 10 of members with the dimensions of the punch and die members of one of the pairs 10 thereof being different from the dimensions of the punch and die members of the other of the pairs 10 thereof, the dimensions of the mounting means, in- eluding the bolt 66, by of the punch ai d die members of one of the pairs 10 of members is removably mounted in the apparatus being the same as the dimensions of the mounting means, including the bolt 66, by which one of the punch and mounted in the apparatus, and the dimensions of the mounting means, intruding the bolt 66, by which the other of the punch and die members of said one of the pairs 10 thereof is removably mounted in the apparatus being the same as the dimensions of the mounting means including the bolt 66, by which the other of the punch and die members of said other of the pairs 10 thereof i3 removably mounted in the apparatus.

With particular reference to the pairs 10 of the punch and die members comprising the punch members 11, IS and. 13 and the die members 16, 17 and 18, it will be noted from , that Fig, 1/for each of these members the associated bolt 66 together with an anti-rotation locking pin 69 constitute a plurality of spaced mounting members. Bach rotation locking pin 69 is disposed partially within a recess provided in the portion 21 of the punch member 11 or 12 or the portion 30 of the punch member 13, or partially within a recess provided in the portion 30 of the die members 16 or 17, or the portion 21 of the die member 13, and partially within a recess provided in the apparatus, and more particularly a bore 70 provided in the appropriate template 61 or 62· The dimensions of the anti-rotation locking pin 69 and the relative spacing between this member 69 and the bolt 66 by the use of which each of the above-mentioned punch and die members is removably mounted in the apparatus are also the same, or at least the dimensions of the anti-rotation locking pin 69 and the spacing between this member 69 and the bolt 66 by the use of which said one of the punch and die members of said one of the pairs 10 of members is removably mounted in the apparatus are the same as the dimensions of the pin 69 and the spacing between this member 69 and the bolt 66 by the use of which said one of the punch and die members of said other of the pairs 10 of members is removably mounted in the apparatus, and the dimensions of the pin 69 and the Spacing between this member 69 and the bolt 66 by the use of which said other of the punch and die members of said one of the pairs 10 of members is removably mounted in the apparatus are the same as the dimensions of the pin 69 and the spacing between this member 69 and the bolt 66 by the use of ^fcioh said other of the punch and die members of said other of said pairs of members is removably mounted in the apparatus. Thus* the position of these pairs 10 of punch and die members in the apparatus may be altered* of some of these pairs 10 of punch and die members may be removed from the apparatus and other pairs 10 of punch and die members substituted therefor. Thust the punch and die members of the or each pair may be readily removed from the apparatus and re-used in a different arrangement* In the described apparatus, adjacent pairs of punch and die members may, if desired, be disposed in substantially contacting s de-by-side relationshp* Furthermore, the described apparatus substantially overcomes or reduces the disadvantages of the previously mentioned prior apparatus.

It is to be understood that the invention is not restricted to apparatus in which the fabricating operations formed on sheet material necessarily constitute the forming of knock-outs in sheet metal panels, and to punch and die members for incorporation in such apparatus.

Claims (4)

Appln.No. 1341/2* 3 C L A I M S i '

1. · A kit of parts comprising at least one pair of members of which one 6f said members is a punch member and the other of said members is a complementary die member for use with said punch member in apparatus for performing fabricating operations on sheet material, said punch and die members each being self-contained and each having screw-threaded mounting means for use in removably mounting said punch or die member as a unit in the apparatus for movement of said punch and die members towards each other into mating juxtaposed relationship for performing a fabricating operation or operations on sheet material disposed therebetween and away from each other, the mounting means of said punch and die members extending in an axial direction in which said punch and die members are movable when removably mounted in the apparatus and being centrally disposed wholly within the respective peripheries of said punch and die members as viewed in said direction, and at least one of said members incorporating a stripper arrangement which is constituted by a stiff but resiliently deformable plastics material and which is eoaxially disposed relative to said axial direction*

2. * A kit of parts according to claim 1, wherein said punch and die members are constructed for the forming of knockouts in sheet material*

3. A kit of parts according to either one of the preceding claims* and including, for each punch and die members mounting means cooperating with said screw-threaded mounting means removably to mount the punch or die member in the apparatus and comprising a single screw- hreaded member which is en- gagable in a screw-threaded recess in said punch or die member, which recess constitutes said screw-threaded mounting means* and each punch or die member having a locating spigot through which the associated screw-threaded recess extends for engagement by the associated screw-threaded member.

4. A kit of parts comprising at least two pairs of punch and die members according to any one of the preceding claims* wherein the dimensions of the punch and die members of one of said pairs thereof are different from the dimensions of the punch and die members of another of said pairs thereof* the dimensions of the mounting means of one of the punch and die members of one of said pairs thereof being the same as the dimensions of the mounting means of one of the punch and die members of another of said pairs thereof* and the dimensions of the mounting means of the other of the punch and die members of said one of said pairs thereof being the same as the di - mensions of the mounting means of the other of the punch and die members of said another of said pairs thereof. 4 al ing in direction in which said punch or die member and the other member which together with said punch or di member constitute one of said pairs of members are relatively movable, and in engagement in said punch or die member and in a template removably mounted in the apparatus, and an anti-rotation locking pin which is spaced from the associated screw-threaded member and which is engaged in recesses provided in said punch or die member and in the template, a locating spigot in which the screw-threaded member is disposed being presented by said punch or die member and being in engagement within a complementary locating recess provided in the template, the spaced mounting members of each of said punch and die members being disposed wholly within the priphery of said punch or die member as viewed in said direction of relative movement, at least one of said members of each of said pairs of members incorporating a stripper arrangement which is constituted by a stiff but resiliently deformable plastics material and which is coaxially disposed relative to said axil direction, and the dimensions of and spacing between the mounting members by which each of said punch and die members are removably mounted in the apparatus being substantially equal.