US2596911A

US2596911A - Sheet metal punching apparatus

Info

Publication number: US2596911A
Application number: US49271A
Authority: US
Inventors: Nelson Harry
Original assignee: LORENTZEN HARDWARE Manufacturing CORP
Current assignee: LORENTZEN HARDWARE Manufacturing CORP
Priority date: 1948-09-14
Filing date: 1948-09-14
Publication date: 1952-05-13
Anticipated expiration: 1969-05-13

Description

May 13, 1952 l-g. NELSON v 2,596,911

SHEET METAL PUNCHING APPARATUS ,mf-M.. HIS ATTORNEYS May 13, 1952 H. NELSON 2,596,911

SHEET METAL PUNCHING APPARATUS Filed sept. 14, 194e 5 sheets heet 2 In n A(9 lNvENToR Q HAM y Naso/v u. BY

l M -Zzav H ls ATTORNEYS May 13, 1952 5 Sheets-Sheet 5 Filed Sept. 14, 1948 HHHHMWIMHI FIG.9

INVENTOR HA RR Y NELSON H IS ATTORNEYS May 13, 1952 v Filed Sept. 14, 1948 H. NELSON SHEET METAL PUNCHING APPARATUS 5 Sheets-Sheet 4 QQ; @g M @I 70 mvENToR HARK V VEZSO/V May 13', 1952 H, NELSON 2,596,911

'SHEET METAL PUNCHING APPARATUS Filed Sept. 14, 1948 5 Sheets-Sheet 5 IIH Illllll 39 32 INVENTOR "BY /0 M/Mvywv H ls ATTORNEYS the passage of the ladder tapes. Y struction is disclosed in'Figs. 6 and 8 in which Fig. 8 is a somewhat diagrammatic view of the cord lock end of a channel-shaped Venetian blind head bar, the bottom wall of which has been punched with the dies shown in Fig. '1.

Fig. 9 is an enlarged fragmentary perspective view showing one of the dies.

Fig. 10 is a top plan View of the die set and channel support, portions of the support being broken away for convenience of illustration.

The operation of the machine shown and an appreciation of its advantages will be facilitated by an understanding of the general construction of the so-called yenclosed metal heads now used in many Venetian blinds.

Where an enclosed metal head is used, the operating mechanism of the blind is entirely contained within a sheet metal head bar whichV is often of channel form. The operating mechanism of the blind includes various fittings such as a cord lock, a tilter and cradles for supporting a tilt vrod running longitudinally of the head bar. I'hese fittings are sometimes anchored to the bottom wall of the channel by tabs which are struck up from the bottom wall thereof.

In the above-mentioned Venetian blind construction, holes must be provided in the bottom wall of the head bar for passage of the longitudinally-extending branches of the ladder tape which supports the blind slats, and for the passage of the tilt cord and lift cords. It has been found to be advantageous. in some instances to form tabs for retaining a tting in position as a whole by I9, 20, 2| and 22, respectively.

These dies are mounted as a single unit for simultaneous operation. Each die consists of a stationary die block and a cooperating set of punches which are telescoped into holes in the die block to form the desired holes and strike the desiredtabs from the head bar I D. Each from `the metalstruck from the bottom wall of the head bar in forming the holes needed for Such a conthe two end portions of a head bar I0 are shown. The head bar I0 vis intended for use in a Venetian blind having a ladder tape adjacent each side of the blind, having a tilter at the left side of the blind and having a lift cord pendant at the right side of the blind. This construction, including the fittings, is shown in more detail in my copending application S. N. 778,002.

For the foregoing head bar construction, a pair of tabs II, II and a U-shaped hole I2 formed at the left end of the head bar I0 may be provided to accommodate a tilter tting and tilt cord. This organization of tabs and hole is centered a constant distance from the left l end of the head bar I0, this distance being indicated by A in Fig. 6. In addition, the left end portion of the head bar III is provided with a pair of tabs I4, I4 and a round hole I5 for receiving a tilt rod cradle and a lift cord. These tabs and hole are not a fixed distance from the left end of the head bar, the distance B of Fig. 6 being varied according to the overall width of the blind. This distance B is known in the trade as the rout distance.

Referring to Fig. 8, a pair of tabs I5, I6 and a hole I1 are provided for the cord lock fitting located at the right end of the head bar. This organization of tabs I6, I6 and hole I1 is centered at a constant distance C from the right end of the head bar, this distance not being varied regardless of the width of the blind. In addition, a group comprising tabs I4, I4 and hole I5 is provided for a second tilt rod cradle fitting positioned in the right end portion of the head bar ID. This group is located a varying rout distance B from the right end of the head bar, according to the width of the blind, and is equal to the rout distance B at the opposite end oi the headbar'. The die 'set to be group of holes and'tabs formed in the bottom wall of the head bar I0 is cut by a separate die. While these dies are varied somewhat in shape for the cutting of the various shaped holes, they are of the same type and are all functionally similar; and only the die I9 will be described in detail.

The die I9 (Fig. 9) includes a die block 24 which may be of composite construction, the top or cutting member 25 ofv the block being formed of suitable alloy steel and the body 26 of the block being formed of ordinary steel for economy and convenience inmanufacture. The cutting member 25 of the block, which may be made of a plurality of individual pieces held together by transverse cap screws .such as 28, is provided with holes shaped and located in correspondence with a group of holes and tabs desired in the bottom wall of the head bar I0, the die of Fig. 9 being adapted for forming the tabs II, II and hole I2 shown in Fig. 6. The entire periphery of the hole I2' provided in the cutting member 25 of the die block, for forming the hole I2 (Fig. 6), is sharpened or squared at the entrance to the hole so as to readily shear the bottom wall of the head bar. However, portions of the holes II, II of the cutting member 25, for forming the tabs II, Il, are rounded at the entrance to the holes to permit bending or striking the tabs from the bottom wall of the head bar without severing the tabs therefrom, the remainder of the peripheries of these holes being sharp to shear the outlines of the tabs. All of the holes in the die block 24 are continued downwardly therethrough (Fig. 3) and through the die block mounting plates in order to pass downwardly the slugs or small scraps of metal cut or torn from the head bar.

The die block 24 is proportioned to fit within the channel I0 and support the bottom wall of the channel against crushing during the punching operation. The die block may be recessed at 23, 23 along both sides near its base to receive the rolled edges of the channel-shaped head -bar I0. Preferably the die block 24 is given a slight extra height so that the dies may be resharpened by grinding a small amount of metal from the top or cutting surface of member 25 so as to renew the cutting edge of holes II', II' and I2.

Cooperating

punches

21, 21 and 2 9 are mount- Yed in a punch plate 3i) for reciprocative telescopto bend the tabs Without cutting its'base thereof.

The organization of punches andidie block for Vvthe dies- 20, 2I- and 22 is essentially the same,

`stripper 39 forftheJdies 20 and 22. --ilper--S'Ifcomprises alsheet metal member of v.gen- .-'era1ly .U-shaped ,form` having its legs securedv -to `-'the-ibase `3l .of the dies Vand extending ninLpa'r-fi'io :aallel'spaced relation upwardly beside landacross '-The'fjdies"are'mounted-side yIcyv sidevin pairs, 1`

blefcksmay be secured toV the bases nby boltspass- 'jing `upwardly throughv bores in' the base, through 4boresin the *body portion of 'fthe die blocks,

and threadedly engaged in the-eutting-members ofthe die blocks (Fig. 3) n 'IlThe-cooperating punches for the fdies-l9, 20,

punches for ythe Adies -I9 -and 12| being mountabove "the `'base J3 I and the' punches for the dies and#parallel to the base '32.

`'The punches-and punch llblocks 'of the 'dies I4are. maintained in Aalignment by seriesof guide A`posts y35fan`ds1eeves-3I5. A guide-post35 profects-upwardly from eachv end portion of eac-h ibase 13| and -32 Vand vis--received byia cooperat- Ling `sleeve 36 :projecting downwardly.' fromv each -fend-ofthe punch plates :30 and34. These guide/- posts and sleeves remain in more orwless tele- -sfscopedvrelation Vat all times, thusaligning `the die ..blocks-.and the punches of the Apair of :dies to .which they arerelated.

RA common l stripper .is provided for :each pair aof. dies, stripper .31 'furthe dies I9 and ZIand YThe strip- :above the 'cutting s surfaces Vof the dies I'9Jand i2I. :The portion .of the stripper 3ll above lthe '.'die-l block 24 1 and the corresponding :die .'.blockffof izfFi'g.f9) of su'icient size to'providefample clear- :1 ance. for Vpassage of the .punches 21,l 21 Sand.29

and likewise is provided-widthr holes V.for .passage :of the .corresponding .punchesvofdieZI -theregt'hrough. :To reinforce the'portion ofthe strip-350 .per :il-extending above the die blocks, upwardlyextending anges 40,149 maybe provided.

Thei-stripperBSis similar in construction Ito Tthe stripper 3'I-.Landisfseeured:to `the basei32 iso fasitoextendzabovezthe dierblo'cksiofdies 29 and i. A:12. The vertical :leg portions -ofitthestrippen 3) may be :'ared1's1ig'htlyfat' their 'front edges'as' indicatedin Figs.3 and 4'toaid in "theinsertion ..ofthechannel-"shaped head'` bar within @the-dies.

:'.Eachl-:of thesestrippers functions vinthefsame :1 manner to;A limit Ythe .upward lmovement of .the head-- bar ,I0 .asrthe punches are .withdrawn from --thepdie blockswsoas. to strip the'v head barirom .the fp unches and retain it, adjacentto thedieblo'cks .so that it maybe twithdrawnlfrom :the dies.

,.rAI-jdievfshoe 42 ;is,provided.forslidablyireceiving feomprisingfa'.horizontal 'plate extending vcorn- "fed-"onfapunchfplate 39 extending parallel to and 120' arrangement 'of y die vshoeil'and'lbases"iislsuehfthat to v`'rear Softthe shoe `while retaining the bases in parallel relation l K The k--punch plates 39 `and 34 are {slidably mounted onf a punoheholdin'g 'plate'f45; this pla'te yextending horizontally` above .both Cof, tlieipnch plates. fCap screws 'lillpassingfthrough slots49 extending i-n the Y. 'punchaholding "-plate S45 from vfront to f'reafr, thereof l ('l'lig.y l0) a-ndlengagedin each endfof each punehplate-f :and v3'4 serve to retain f the -punch 'plates vin f position. lt l[has been rfound vto be unnecessary to provide Tvthe l punchholding lplate I-4`5 -with side lguides lrltoivetainthe` punch platesLSIliandf 341 i-nparallellrelaf tion. (The l punohsholding i; plate i155 is provided 'with-a conventionalround upwardly-entendi@ 'shank-"'62 (Figi 10) for secuningltheplateto the 4311oated within theslee'ves' for lubricatingfthe sleeves and -gV-uide posts? 3' 5 'The dies Z9' and IFS-'are lnfrountedV on therb'ases 132 and-43|, respectively, aligned from f-rontflto "rea-r tolreceive an `endffftlfie channel-shaped ets,

headfbar ZIU. "The dies 2li-andY 225aref'sixnilarly '-afligne'd; for receiving the opposite y en'd 'of *the vthe head bar "end "forend and inserting 'theopposite end within the dies 2I and 22;theopposit`e l end ,of the' head bar' is punched as 'indica-ted vin Fig. V8. l

ifThe stops 50 and -5 I 'are 'jprcwidedV o'nthe "rear side of die -blonek 24 'offdie-I'9 Aand Ithe-"die"bleek of ldieffzl (Figs. '5 andj-f7 ftoiimit tnefrearward -movement of the -ends` 'of Athe head' 'bar' I fwhen it is inserted within lthe dies. Eachptthese stops comprises a shortstrip fof; metal-v secured to the rearfface ofthedieblockandprojeeting aboveV the cuttinglsurfaceiltliereof. f'W'hen inserting the head-bar drwthinrhediesitis .shdreair- [holes and tabsformedpy :dies 1I'9 ;and;2|;are formed La Y constantldistance from j the ends fof the head bar.

Head `bars, vof varying. `rout ,distance 4.may "be n'the handed threads "formed ,ontsfrontfpdrtion and V-in fone diretion, onpair, o'f-diesisfseparatd 'fromjthe ot,herpairl andup'on rotationr in lrevei'jse direction the 1 pairs of `dies are l converged. The vshaft' v52 retained "against longitudinal vInove- 7 This arrangement maintains the pairs of dies always centered relative to the ram 46 of the press and therefor aids in maintaining a more symmetrical loading of the dies.

The forward end of the shaft 52 may be provided with a socket E similar to the head of an Allen-type screw. A relatively small crank 5i is provided with a cooperating male portion for engaging the socket 5B in order to operate the shaft. The crank 51 may be retained captive on the dies IS by a link 59 having one end pivotally secured to the forward edge of the die shoe 42 and the opposite end journaled about the shaft-engaging portion of the crank.

Bolts 60 (Fig 3) may be provided passing through slots 6| extending from front to rear in the die shoe 42, threadedly engaged in the bases 3| and 32, these bolts and slots being similar to the bolts 41 and slots 4S previously described in connection with the punch-holding plate 45 and the

punch plates

30 and 34. The bolts 60 serve to hold the bases 3| and 32 tightly to the die shoe 42 to hold the dies I9 in fixed adjustment when the rout distance is not to be varied, these bolts supplementing the

guides

44, 44.

The rout distance is adjusted by rotating the shaft 52 after slightly loosening the bolts 41 and 60. Rotation of the shaft 52 converges or separates the pair of dies as a unit together with their associated bases, punch plates and guides 35. In this manner, the rout distance for both ends of the head bar is adjusted simultaneously in the same amount by a single adjustment, helping to prevent errors in adjusting and assuring a completely uniform rout distance at both ends of the head bar.

A scale 64 may be mounted on one end of the punch plate 30 (Fig. l) to extend forwardly beside the corresponding end of the punch plate 34. A pointer 65 mounted on the punch plate 34 indicates on a portion of the scale 64, graduated in inches, the rout distance for which the dies are set.

A support 66 projects forwardly from the dies 22 for supporting the free ends of the head bar I0 at the proper elevation for the stamping operation. This support comprises a pair of forwardly-extending

members

61, 61 secured to the die shoe 42 and a horizontal-connecting member 69 connecting the forward ends of the

members

61, 61 and so positioned that when a head bar I0 is supported on the member 69, in inverted position, the bottom wall of the head bar will lie in a plane continguous to the top surface of the die blocks.

A vertical guide 10 projects upwardly from the member 69 and is aligned with the space between the dies 26 and 22 to aid in positioning a head bar for the stamping operation. In stamping the right-hand end of the head bar |0, the head bar is placed in inverted position on the member 69 to the left of the guide 10 and the end of the bar inserted within the dies 22 and 2|, the free end portion of the head bar being supported on the member 69 and resting against the left side of the guide 10. In stamping the left-hand end of the head bar I0, the head bar is placed in inverted position on the member 69 to the right of the guide 18, and the other end of the head bar is inserted within the dies 20 and I9, the free end portion of the head bar being held against the right face 0f the guide 10. The guide 10 serves to keep the free end of the .head 'bar l0 aligned with the guides both horizontally and-.vertically andv serves as a handy 8 guide for insertion of the ends of the head bar Within the dies.

The press 1I for holding and operating the die set 22 may .be a conventional mechanical power press of live ton capacity. This press has a bed 12 to which the die shoe 42 may be bolted, the shank 62 of the punch-holding plate 45 being received by the ram 46 of the press. A trip lever 14 serves to control the operation of the press, depression of this lever resulting in a single stroke and return of the ram 46 so as to complete a single stamping operation of the dies 22. A receptacle 15 may be positioned adjacent the bed 12 of the press below the die set |8 to receive metal scraps and slugs.

I claim: l

1. Sheet metal punching dies comprising tw pairs of simultaneously operable dies,including die blocks and reciprocable punches, each pair of dies being carried by a separate base and punch plate and being relatively movable to adjust the distance between the pairs of dies, the corresponding dies of each pair being aligned for receiving an end of an elongated member and punching a plurality of holes therein in a single operation, and the two dies of at least one of the pairs being differently shaped so as to punch non-similar holes in the two ends of the elongated member, and means for accurately locating the ends of the member relative to the dies during the punching operations.

2. Sheet metal punching dies comprising two pairs of simultaneously operable dies, including die blocks and reciprocable punches, each pair of dies being carried by a separate base and punch plate and being relatively movable to adjust the distance between the pairs of dies, and telescoping guides for maintaining the die blocks and punches in alignment, the corresponding dies of each pair being aligned for receiving an end of an elongated member and punching a plurality of holes therein in a single operation, and the two dies of at least one of the pairs being dierently shaped so as to punch nonsimilar holes in the two ends of the elongated member, and means for accurately locating the ends of the member relative to the diesA during the punching operations.

3. Sheet metal punching dies comprising two pairs of simultaneously operable dies, including die blocks and reciprocable punches, each pair of dies ,being carried by a separate base and punch plate and being relatively movable to adjust the distance between the pairs of dies, and a die shoe and punch-holding plate mounting the bases and punch plates, respectively, the

, corresponding dies of each pair being aligned for receiving an end of an elongated member and punching a plurality of holes therein in a single operation, and the two dies of at least one of the pairs being diiferently shaped so as to punch non-similar holes in the two ends of theelcngated member, and means for-accurately locating the ends of the member relative to the dies during the punching operations.

4. Sheet metal punching dies comprising two pairs of simultaneously operable dies, including die blocks and reciprocable punches, each pair of dies being carried by a separate base and punch plate, a die shoe and punch-holding plate movably mounting the bases and punch plates, respectively, and means for moving each pair of diesl equal amounts to adjust the distance between the pairs, the corresponding dies of each lpair being aligned for 4receiving an end of an elongated member and punching a plurality of holes therein in a single operation, and the two dies of one of the pairs being differently shaped so as to punch non-similar holes in the two ends oi the elongated member, and means for accurately locating the ends of the member relative to the dies during the punching operations.

5. Sheet metal punching dies for punching an elongated metal member, said dies comprising a pair of simultaneously operable dies, including die blocks and punches, mounted side by side in spaced relation, a second pair of dies mounted behind and aligned with the first-mentioned pair of dies, and a support projecting forwardly from the dies for supporting the free end of elongated members inserted within the dies, said support having a member-supporting surface extending in front of the dies and a guiole member projecting above the member-supporting surface intermediate its ends and aligned with the space between the dies, and the two dies of at least one of the pairs being dilerently shaped so as to punch non-similar holes in the two ends of the elongated member, and means for accurately locating the ends of the member relative to the dies during the punching operations.

6. Sheet metal punching dies for punching an elongated metal member, said dies comprising a pair of simultaneously operable dies, including die blocks and punches, mounted side by side in spaced relation, a second pair of dies mounted behind and aligned with the first-mentioned pair of dies, the two pairs of dies being relatively movable from front to rear to adjust the distance between the pairs of dies, and a support projecting forwardly from the dies for supporting the free end of elongated members inserted within the dies and the two dies of one of the pairs being differently shaped so as to punch non-similar holes in the two ends of the elongated member, means for accurately locating the ends of the member relative to the dies during the punching operations, said support having a member-supporting surface extending in front of the dies and a guide member projecting above the member-supporting surface intermediate its ends and aligned with the space between the dies.

7. Dies for punching the bottom wall of a sheet metal Venetian blind head bar channel, said dies comprising two pairs of simultaneously operable dies, including die blocks adapted to fit within the channel to support the bottom wall and cooperating reciprocable punches. each pair of dies being separately mounted and relatively movable to adjust the distance between the pairs of dies to vary the rout distance, the corresponding die blocks of each pair being aligned from front to rear to receive the channel in inverted position for punching a plurality of holes therein in a single operation, and the two dies of one of the pairs being diierently shaped so as to punch non-similar holes in the two ends of the channel, and stop members adjacent one of the pairs of dies and engageable by the ends of the channel to limit insertion of the channel within the dies, the die blocks tting closely between the side walls of the channel and, together with the stops, serving to accurately locate the ends of the channel during the punching operations.

8. Dies for punching the bottom wall of a sheet metal Venetian blind head bar channel, said dies comprising two pairs of simultaneously operable dies, including die blocks adapted to nt within the channel to support the bottom wall and cooperating reciprocable punches, separate plates mounting each pair of die blocks and the punches of each pair of dies, telescoping guides connecting the plate mounting the die blocks and punches of each pair of dies, and a die shoe and punch-holding plate slidably receiving the plates mounting the dies and punches to adjust the distance between the pairs of dies to vary the rout distance, the corresponding die blocks of each pair being aligned from front to rear to receive the channel in inverted position for punching a plurality of holes therein in a single operation, and the two dies of one of the pairs being differently shaped so as to punch nonsimilar holes in the two ends of the channel, and stop members adjacent one of the pairs of dies engageable by the ends of the channel to limit insertion of the channel within the dies, the die blocks iitting closely between the side walls of the channel and. together with the stops, serving to accurately locate the ends of the channel during the punching operations.

HARRY NELSON.

REFERENCES CITED The following references are oi record in the file of this patent:A

UNITED .STATES PATENTS Number Name Date 521,654 Ireland June 19, 1894 743,620 Crossley Nov. 10, 1903 1,667,028 Boynton Apr. 24, 1928 1,796,939 Pollasky Mar. 17, 1931 1,874,068 Walker Aug. 30, 1932 1,939,478 Whistler Dec. 12, 1933 2,209,407 Lindsay July 30, 1940 2,251,433 Wareham Aug. 5, 1941 2,381,062 Kirsch Aug. 7, 1945 FOREIGN PATENTS Number Country Date 2,139 Great Britain Aug. 15, 187i 28,027 Great Britain Dec. 5, 1912