US2748865A

US2748865A - Punch press and feed mechanism therefor

Info

Publication number: US2748865A
Application number: US212975A
Authority: US
Inventors: George H Kuhl
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-02-27
Filing date: 1951-02-27
Publication date: 1956-06-05
Anticipated expiration: 1973-06-05

Description

June 5, 1956 G. H. KUHL PUNCH PRESS AND FEED MECHANISM THEREFOR Filed Feb. 27, 1951 6 Sheets-Sheet l June 5, 1956 G. H. KUHL 2,748,865

V PUNCH PRESS AND FEED MECHANISM THEREFOR Filed F'Sb. 27, 1951 5 SheeJLS-Sheet 2 Filed Feb. 27, 1951 June 5, 1 956 G. H. KUHL 2,748,865

PUNCH PRESS AND FEED MECHANISM THEREFOR 6 Sheets-Sheet 3 607 e @4 {KIQ/JM] W G. H. KUHL PUNCH PRESS AND FEED IVIECI-INISMv THEREOR `lune 5, 1956 6 Sheets-Sheet 4 Filed Febr. 27, 1951 w Wh I M M m W WNS WMS

` June 5, 1956 G. H. KUHL.

PUNCH PRESS AND FEED MECHANISM THEREFOR 6 Sheets-Sheet 5 Filed Feb. 27, 1951 June 5, 1956 G. H. KUHL PUNCH PRESS AND FEED MECHANISM THEREFOR 6 Sheets-Sheet 6 Filed Feb. 27, 1951 Gewyj, J1 425 United States Patent O PUNCH PRESS AND FEED MEHANISM George H. Kuhl, Glen Ellyn, I'li.

Application February 327, .1951, Serial No.12'12^975 1 Claim. '(Cl. 164-117) 'This invention relates to a punch rpress and feed means therefor.

It is the general object of this invention to ,produce a new and improved punch y.press and new and'improved feed means which is particularly adapted for use with a Ipunch press.

Another object of 'the .invention is to produce a dual punch press which includes a .ram carrying two male die Ipar'ts and mounted 'for reciprocation 'in a horizontal plane, and two 'female die parts each cooperable with one of the male die parts .so 'that two punching opera- 'tions can be accomplished in each vstroke of the press.

@It is a lmore specific object of 'theinvention to produce a dual Apunch press of the ltype described in the preceding paragraph which includes means .'for accurately adjustving each male die part relative 'to the other Vparts o'f the ,press in order 'to secure perfect alignment of the dies.

It is a further object o'f this invention to produce in a single apparatus a self-feeding punch ,press which .may operate not only on one but two die sets simultaneously, 'each 'die producing either a similar or a dissimilar -part and capable of operating at higher rates of speed and productivity by reason o'f improved .distribution and pro portion of moving and stationary masses of the press.

It fis another object of the lirn'lent'ion to produce a sel`f- Lfeeding punch .press which ,puts 'to use the return stroke 'of the ra'm andlthus to increase Athe productivity of punch presses without Va corresponding increase .in `cost or size.

Another object of the invention is to produce a Ifeed 'means which 'is provided with means defining a nip through vwhich Jthe work piece .is led and including means for intermittently opening and closing the nip to grip the workpiece therein intermittently to feed 'the work piece TO Il t'Ol.

A further object 'of "the invention is to produce a "feed means for feeding l-a work piece to 'a reciprocating .punch press and provided With a 'pair of 'driven rolls between he 'nip fof which `the work piece is led, together with 'means driven 'in timed relationship with the recipro'cation of the press `for opening and closing the nip intermittently Ito :.tfllvance vthe work piece to the press.

A further object of the invention is 'to Aproduce 'a 'feed 'means vof the type described inthe preceding Aparagraphs which includes a cam driven by the drive means for the press ltogether lwith lever means operated by the cam for `opening and 'closing the nip 'in 'timed 'sequence with the operation of the ftool.

'Yet another object o'f the invention is to ,provide a feed 'means having 'a pair of Adriven Iro'lls vthrough which :the yworkpiece is passed 'withone vof the rolls being movalale ftoward and away from *the other roll `to open and 'dlose the nip ibetween '-rolls 'intermittently kto advance -the workpiece, the lopening and closing of the nip being accomplished by meansofa 'cam ydri-ven -by the drive means for the press and contacting a cam follower which forms a part of a lever means for moving the roll.

'Yet another object 'of the invention Eis -to 'produce 'a ICC '2 feed .means of the type described in the preceding ,paragraph in which the cam follower .is adjustable relative to the lever means to adjust the dwell of 'the rolls in the opened and closed position to regulate the length of the work piece Lfed each time the nip is closed.

Other and further objects of the invention will be apparent 'from the following description and drawings, in which:

Fig. 1 is a side elevation of a dual punch press embodying the invention;

Fig. l2 vis an end view of the upper portion of Fig. l;

Fig. 3 is a top plan view of the apparatus shown in Fig. l;

Fig. 4 is a vertical section 'along line 4 4 of Fig. '3;

Fig. 5 is a side elevation of the upper portion of Fig. l showing the opposite 'side of 'the press;

Fig. L6 i's a vertical 'section 'along line 6---6 of Fig. 5;

Fig. 7 is a vertical section along line 7 7 of Fig. 3'; and

Fig. 8 isa horizontal section along line S`8 of Fig. 7.

While this invention is 'susceptible of embodiment in man-y dierent forms, there is shown in -the drawings Vand will herein AAbe described in detail one specific 'embodizmerit, with 'the understanding 4that the present disclosure is to 4'be 'considered as an entempliiication of *the principles "of the invention and is not intended to limit the linvention to the embodiment illustrated. The scope of the 'invention will be pointed out in Ithe appended claim.

For the purpose-of'exemplary disclosure the feed means of this mvention is shown vas used in yconjunction with 'a 'dual punch press. As `shown in the drawings the press yincludes a frame A supporting the press B, drive means fCfor driving the press and the feed 'means D for feeding the work piece to the press.

The 'frame A includes rigid legs -11'0 adapted to support :the apparatus, the legs preferably being angle irons welded orfotherwise secured :together to provide a Asturdy mounting. VThe press B is supported on the top 'of the Aframe and includes la pair of bolster plates *Zik and 2l secured to the frame A 'at spaced positions and upstandling verticaily therefrom i-n parallel relationship to -ea'ch other. Extending 'between and secu-red A'to each Aof the fbols'ter plates are lfour ft-ie 'rods '22425 which provide vthe mounting means for the movable ram of the jpress. The ends of the Itie rods are securely 'fastened to "the bolster ,plates by the 4bolts shown. Pour 5bearings 26-2'9 fare :provided for carrying fthe ram, each of 'the bearings being fs'lidaroly :mounted upon a-different'one of the rods.

lIt sviil be noted that tihe press reciprocates horizontally. This fact, .together with the :low center of gravity fof the apparatus, increases the `stability of the press and -pe-Hn-its .thigh 'speed operation.

As best .shown in Fi'gs. 4 and 5, .the beanings 'are intelgra'lly fsec'ured to an :annular collar member 30 fforming ra ip'arit yof the sram tand which Jis provided lwith .an vinternal recess Secured in :the .recess :as by "thes'crew devices '.32 :is ian :externally threaded annular .sleeve 33 which extends ooth ways ffrom the recess Y31 and parallel with lthe tie rods. The :sleeve 53 is aprovi'ded with an integral flange rer/.tending 'radially outwardly 'therefrom and pro- `'vided withxan ntemalfchannelil 'located #in the Irecess Si and receives the screw devices 32 previously described.

.As previously stated, ithe particular 'embodiment of the :invention fch'o'sen for illustration is yshown as used With a ualpunch press, that is a punch press which -has 'similar 'lparts on each lside and is ladapted `(to perform a punching operation up on each hal-f stroke 'as 'it is 'reciprocated Thus, the parts of the press to the left Aand to the right of the recess 31 (as vseenfin Fig. 4) 'are similar. In order to avoid unnecessary `repetitions 'only 'the die vfpart on one side of the recess -31'will'bedescibedin detail, 'it lbeing 3 understood that the description applies to the die parts on the other side of the ange to which similar reference numerals carrying the letter a have been given.

A punch holder 40 is provided with an annular restricted portion 41 received within the sleeve 33 and with an outwardly extending annular portion 42 provided with external threads 43 which lie in the same plane as the threads 35 of the sleeve. The sleeves 33, however, are turned oppositely to the threads 35, for example the threads 43 may be right-hand threads while the threads 35 may be left-hand threads. A collar member 45 is provided With internal threads which engage both of the

threads

43 and 35 so that rotation of the collar member 45 serves to move the punch holder 40 inwardly and outwardly with respect to the sleeve 33. The outer face 46 of the punch holder 40 is concave in shape and preferably is shaped as a section of a sphere. Coinciding with the concave face 46 is a convexly spherical shaped member 47 secured to the male die plate 48.

A centrally located lug 49 is secured to the die plate 48 and received in a recess 50 in the punch holder 40. As will be noted from the drawings, the recess 50 is larger than the lug 49 so that the die plate 48 may be shifted slightly accurately to position 4it parallel to the bolster plates. This adjustment may be utilized to compensate for manufacturing inaccuracies and its provision minimizes precision operations in the building of the press which would otherwise be necessary if the adjustment were not provided as it is necessary that the surfaces of the ram be perfectly parallel to the bolster plates. The loose fit between the lug and recess permits such alignment and a plurality of screws 51 are provided in the punch holder 40 and to clamp the male die part of the ram in properly aligned position. Preferably three such screws 51 are provided equally spaced about the boss. Secured to the die plate 48 is a die carrying plate 52 which carries the

male dies

53 and 54.

The particularly press illustrated has been set up to carry male dies for forming washers from a continuous strip of material. Thus the die 53 serves to cut a circular hole in the material while the die 54 makes a second circular cut having a larger diameter than the first cut to form the annular washer. Scrap material is cut from the strip by

cutter blades

55 and 55a each fixed to the bottom of each of the male die parts and adapted to cut the strip against a recess formed in the opposing face of the female part of the die.

A pair of studs 56 and 56a is fixed in each of the bolster plates and extend toward the ram parallel to the tie rods. A pair of sleeves 57 and 57a is fixed to each of the male die parts and slide on the studs in order to serve as guides for the ram during its reciprocation. It will be noted that the studs and

sleeves

56 and 57 are in vertical alignment along one side of the male die part 48 while the studs and sleeves 56a and 57a are in vertical alignment along the opposite side of the male die part 48a.

To the right of the male die plate is a female die plate 60 provided with

suitable openings

61 and 62 matching the male die parts. The female die plate 60 is supported against

spacer plates

63 and 64, the latter being secured to the bolster plate 20. Each of the spacer plates is provided with holes extending therethrough matching the

holes

61 and 62 to provide the elongated passages shown which open into an annular recess 65 provided in the bolster plate.

Between the male and female die parts there is provided a stripper plate 66 also provided with openings matching the

openings

61 and 62 and spaced from the female plate to define a passage 67 through which the strip of material constituting the work piece is fed.

As the die is reciprocated and the work piece is fed into positions in line with the dies, the first die 53 cuts a circular opening in the strip each time the die is reciprocated. The circular plugs which are cut out by the die 3 stack up in the passage 61 and are moved therealong as the work progresses and finally drop into the annular recess 65. Similarly, the male die part 54 completes the cutting operation to form the washer, the washers stacking up in the openings 62 and Imoving therealong in the same manner as the plugs. It is preferred that the male die part be provided with a projecting boss 68 properly to align the work piece with the cutting edges of that die in order to insure that the washers be accurately formed.

A pair of chutes 70 and 70a communicate with the recesses 65 and 65a respectively to guide the washers as they fall from the recesses into a pair of containers 71 and 71a located at the bottom portion of the frame (Fig. l). I prefer to provide two such containers inasmuch as the die parts on either side of the ram may not be similar in nature, thus for example one die part may be cutting washers having a 1 inch diameter and the other washers having a 11/2 inch diameter. The provision of two containers, one communicating with each of the recesses in the holsters permits the segregation at the machine of differently formed parts. If desired, a separate chute may connect with the opening 61 to separate the plugs from the washers.

Scrap material from the press continues its downward movement in the recess 67 until it strikes an inclined plate 72 supported on

brackets

73 and 74 secured to the frame, which plate directs the scrap material into a container pan 75 (Fig. 3) located in the lower part of the frame.

The drive means C include a motor connected by means of a V belt 81 to a rotatably mounted pulley 82. A pair of V belts 83 connect the pulley with a rotatably mounted flywheel 84. The ywheel carries a crank 85 on either side thereof to each of which is secured a pitman 86. The two pitmans so provided are each connected to opposite sides of the die, that is to the annular collar 30 which is carried by the slides.

The flywheel 84 is fixed to a rotatably mounted shaft 87 supported at both ends in the frame and to which is fixed a gear 88 meshing with a second gear 89. The ratio of the massof the flywheel to the mass of the male die carrying parts is high to provide sutlicient inertia for the press to perform a punching operation on each stroke. Also the high mass ratio contributes to the stability of the press. The gear 89 is fixed to a shaft 90 which carries at its outer end (Fig. 3) a pair of meshing bevel gears 91 one of which is secured to a drive shaft 92. The drive shaft 92 serves to operate the feed means D which in turn serves to advance the work piece intermittently to the die as the latter is reciprocated.

Inasmueh as the press illustrated in the drawings is a dual press two feed means are provided, one for each press. While the feed means are similarly constructed (and similar parts will be given similar reference numerals with the letter a added) each may be adjusted individually so as to feed at different rates. Thus if the press is performing two distinct operations, one on each die, feed means may be individually adjusted to feed the work piece at the proper rate in order to accommodate the operations of each press.

When used with a dual press, the work piece which is in the form of strips of material and 100a, is fed from an overhead source which may be large rolls over which the material is passed. As the strips enter the press each is passed over a guide roller 101 rotatably mounted in a fitting 102 secured to the top of the feed means. A friction device 103 is provided to produce the proper tension on the work piece, the friction device including a shoe 104 fixed to the fitting 102 and a second shoe 105 slidably mounted on bolts `106 and urged against the first shoe by means of a spring 107. The degree of friction may, of course, be adjusted by adjusting the screws Adjustably secured to the top of the bolsters 20 and 21 is a mounting frame for the feed means including two spaced upright parallel plates and 111 secured at Javanese their bottom to Ybase plate-s 11.12 and 11113. Secured to and extending horizontally between *the =bas`e plates is a -rst clamping plate 114. A secc-nd clamping plate 115 is vertically spaced beneath the ftirst clamping plate and secured thereto by 'means of bolts 1.1116. A pair of spaced parallel horizontal shafts 117 and 118-are secured to the bolster plate and serve as 'the mounting means for the feed mechanism. As wil-1 he noted 'from an inspection "of Figs. '4 and -6, the

base plates

112 and 113 are positionen above the 'shafts 117, 1178 while the clamping plate 115 is positioned beneath the shafts. Each of 'the base plates and 'the 'clamping plates is provided with substantially henri-cylindrical 'grooves m'ore 'accurately to t the outer surfaces 'of the 'shafts 1117 and 11% and thus v"the entiremounting means 'may be slid along the 'shafts 117 and 11,3 and clamped thereto 'at any desired point. Thus adjustment can be made for various 'thicknesses "of the workpiece and for various Workin-'g :strokes of the press. Furthermore, the adjustment of the feed units makes it possible to align the entrance of the strip into the feed means exactly opposite the exit of the strip therefrom and perfectly aligned with the dies of the press to enable a large variety of die sets to be used in the press.

Referring now to Figs. 7 and 8, it will be noted that the side plate 110 is provided with a rect-angular cut-out portion 120 in which there is slidably mounted a block 121 which rotatably carries one end of a shaft 122 on which Ithere is fixed a feed roller 123. A similarly constructed block is slidably mounted in the plate 111 and carries the other end of shaft 122. Fixed adjacent the right-hand end (as seen in those figures) of the plates 110 and 111 is a second rotatably mounted shaft 125 to which is fixed a second feed roller 126. The roller 126 is, as clearly shown in the drawing, mounted in parallel to the roller 123 and forms therewith a nip 127 through which the work strip 100 may be led.

Each of the

feed rollers

123 and 126 is driven from the drive means of the machine. As best seen in Figs. 3 and 6, the drive shaft 92 is provided with two pairs of bevel gears 130 and 131m, one of which carries a sprocket 131 over which a chain 132 is passed. The chain engages a second sprocket 133 secured to one end of the shaft 125 for driving the same. Intermediate sprockets 134 and 135 are provided to take up the slack as the feed means may be adjusted inwardly and outwardly as previously described. Mounted on the shaft 125 adjacent the feed roll 126 is a spur gear 140 which meshes with a second spur gear 141 fixed on the shaft 122. Thus as the press is operated both of the feed rolls are positively driven.

It will be clear from the foregoing description that if the two feed rolls are pressed together to close the nip between them the strip of material 100 would be constantly fed to the press. This, of course, is not the object to be achieved in the particular type of press shown inasmuch as the press requires that the material be fed intermittently, that is, be advanced as the die parts are moved away from each other to present a fresh portion of the strip and held stationary as the die parts are Ibrought together to perform their punching operation. Means are provided for alternately open-ing and closing the nip between the rolls, so that when the nip is closed the material is firmly grasped by the rolls and fed downwardly to the press. As the nip is opened both rolls lose their frictionlal grasp of the material and hence the frictional device holds the strip stationary against advancement until the nip is again closed.

To effect the alternate opening and closing of the nip, the shaft 125 rotatably carries a cam 149 which cam may be xed thereto by a plurality of set screws 150. The shaft is rotated in synchronism with operation of the press by the drive means C. A cam follower 151 rides upon the cam and is mounted in a lever arm 152 which is fixed to a shaft 153 rotatably mounted in the plates 110, 111, by a split clamp formed in the end of the lever arm through which clamp a lock sc-rew 154 extends. As best 'shown vin Fig. f8, the shaft Y15?) extends through the rectangular vcut-out portion in the side plate 110 and is provided with a flattened portion .15'5 located in 'a cutout port-ion V156 -of the block 121 and `bearing against a flat `face 157 thereof. A compression spring 158 yhas one end located in a recessed portion 159 at the end `of the plate 1-10 `while its other end bears against the ladjacent face Iof the slidable block 1,21 to urge the block constantly 4in 'a direction 'closing the nip between the feed rolls. The force with which the spring biases the nip toward closed position may be adjusted in the usual -man- :ner by means vof the screw Vdevice -1-60. The ypreviously described vadjustment vof the lever arm relative to the shaft ,-1-53 afforded by the split clamp and lock screw :154 yis provided to take advantage of :the most rapid rise of the edge of the attened 'surface 155 against the face 1'57 whenever -a cha-nge is made from one thickness of stock toanother.

`From the foregoing it can be seen that as the shaft 153 is intermittently osoillated one edge of the flattened portion thereof is brought against the face 157 of the block to shift the block laterally against the spring. Inasmuch as the feed roller "123 is mounted in the block, such shifting movement of the block serves to open the nip between the rolls.

It will be noted that the cam follower 151 is mounted on the end of a bolt 162 which is threadable on the free end of the lever ann 152. A lock nut 163 is provided to lock the cam follower at any position to which it may be moved by adjustment of the bolt 162. By so adjusting the cam follower it is clear that the period of dwell of the rolls in the open nip or closed nip position may be regulated. Inasmuch as the strip is fed toward the die parts only when the nip is closed such adjustment permits regulation of the amount of material fed during each cycle of the die. Thus if the nip remains closed for a greater proportion of the cycle a longer length of material is fed than otherwise.

The timing of the opening and closing of the nip may be adjusted relative to the reciprocation of the die parts rotating the cam upon its shaft. By loosening the set screws 150 the cam may be rotated in either direction relative to its shaft and fixed in any desired position. Thus there is provided a simple means of timing the feed of the work strip relative to the closing of the die parts. If the operator finds that the strip is in motion at the time the die parts are closed the press may be stopped and the cam 149 adjusted so as to open the nips slightly sooner in the cycle of the die. Again if the length of the strip to be fed during each cycle of the die is great the cam can be adjusted on its shaft so as to feed the strip during substantially the entire cycle, the nip opening just prior or simultaneously with the contact of the male die part therewith.

In the particular embodiment of the feed means chosen for illustrating the invention, manual means are provided for opening the nip between the feed rolls at any time in the cycle of the press, which means serves to maintain the nip open until manually closed. To this end a shaft is rotatably mounted in the plate 111 (Figs. 6 and 7) to which is secured a handle 171 for rotating the shaft. The inner end of the shaft carries an eccentric pin 172 which bears against the bottom face of the lever arm 152. Rotation of the handle in a clockwise direction (as viewed in Fig. 7) serves to lift the lever arm and hence to open the nip between the rolls. The nip will remain open until the direction of rotation of the handle is reversed permitting the cam 149 to resume control of the nip position.

I claim:

In combination with a reciprocatory punch press having a frame and power drive means for reciprocating the ram of the press, feed means for feeding a continuous strip of material to the press comprising means defining a pair of parallel spaced guideways on the frame, a block slidably received in each guideway, a first feed roll shaft,

7 means on each block for rotatably supporting the ends of the feed roll shaft, a second feed roll shaft rotatably mounted in the frame and positioned parallel to and adjacent the first feed roll shaft, a feed roll on each shaft, an actuating shaft rotatably supported in the frame and provided with a attened portion contacting each block, resilient means urging the blocks toward movement in one direction, a cam mounted on the second shaft, a cam follower riding on the cam, a lever arm adjustably secured to the cam follower and xed to the actuating shaft, means for adjusting the cam follower relative to the lever arm to vary the period that the nip is closed, said lever arm operating to rotate the shaft to slide the blocks in the other direction each time the cam is rotated whereby to open and close the nip between said feed rolls, means for rotatably adjusting the cam relative to the second shaft to determine the point in the cycle of press operation at which said nip is closed, means for feeding a strip of the 8 material into said nip, and means connecting the second shaft to the drive means.

References Cited in the file of this patent UNITED STATES PATENTS 642,901 Glader Feb. 6, 1900 854,706 Eden May 2l, 1907 907,812 Junkins Dec. 29, 1908 938,453 Bernard Oct. 26, 1909 963,828 Swift July 12, 1910 1,706,729 Gauthier Mar. 26, 1929 1,821,899 Schneider Sept. 1, 1931 1,978,303 Guett Oct. 23, 1934 2,261,703 Tatzlatf Nov. 4, 1941 2,265,332 Woodington Dec. 9, 1941 2,268,242 Candee et al. Dec. 30, 1941 2,339,962 St. Louis Ian. 25, 1944