US3176568A

US3176568A - Microset punch

Info

Publication number: US3176568A
Application number: US241794A
Authority: US
Inventors: James W Bradley
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-12-03
Filing date: 1962-12-03
Publication date: 1965-04-06
Anticipated expiration: 1982-04-06

Description

J. W. BRADLEY MICROSET PUNCH April 6, 1965 2 Sheets-Sheet 1 Filed Dec. 5, 1962 \Nv Aww NNN www@ April 6, 1965 J. w. BRADLEY 3,176,568

MICROSET PUNCH Filed Dec. 3. 1962 2 Sheets-Sheet 2 f6 fr ff! ff INVENTOR United States Patent 3,176,568 WCRQSET PUNCH James W. Bradley,1185 ahdale Road, Atlanta, Ga. Filed Dec. 3, 1962, Ser. No. 241,794 1 Claim. (Cl. S21- 468) The present invention relates to punches and especially to punches adapted to punch holes in a sheet metal strip to an accuracy of .0001 inch.

A purpose of the invention is to provide for successively punching a plurality of holes in a longitudinal strip spaced to a very accurate degree.

A further purpose is to provide a punch which will eliminate cumulative error in spacing between successively punched holes.

A further purpose is to punch a template having holes with centers at precisely spaced locations.

A further purpose is to provide a punch which can exactly duplicate center distances between a plurality of punched holes.

A further purpose is to provide a punch for punching holes at spaced locations in a longitudinal strip.

A further purpose is to provide a punch for forming a template capable of keeping perfect registration for a series of exposures on a step and repeat machine.

A further purpose is to provide a punch for forming a template capable of. duplicating spacings in a step and repeat machine.

A further purpose is to provide a punch with a locating abutment which is first positioned roughly by means of a linear scale and then is positioned accurately by means of a Vernier.

Further purposes appear in the specification and in the claim.

In the drawings l have chosen to illustrate one only of the numerous embodiments in which my invention may appear, selecting the form shown from the standpoints of convenience in illustration, satisfactory operation and clear demonstration of the principles involved.

FEGURE 1 is a plan view of the punch of the invention.

FIGURE 2 is a front elevation of the punch of the invention.

FEGURE 3 is a fragmentary enlarged plan view of the micrometer head Vof the punch of FIGURES 1 and 2.

FIGURE 4 is a right side elevation of the punch of the invention.

FGURE 5 is an enlarged sectional elevational view taken on the line 5-5 of FIGURE 1.

FIGURE 6 is an enlarged sectional elevational view taken on the line 6 6 of FIGURE 1.

FIGURE 7 is a fragmentary plan view of the control strip punched in the punch of FIGURES 1 to 6.

The present invention provides accurately punched longitudinal strips or templates, particularly for indexing a step-and-repeat machine of the type as set forth in application Serial No. 241,850, filed December 3, 1962, for Step-and-Repeat Machine. In strip templates of this type, it is necessary to have the holes of the same diameter spaced accurately apart. It is further necessary for the spacing between the holes to be exact duplicates of one another.

In the prior art, it has been customary to move the punch or to move the locator intermittently to provide a spacing between the punched holes. The spacing or movement of the punch or locator was usually accomplished by an index and linear scale.

ln accordance with the present invention, the locating pin and the punch are fixed with respect to one another, and the entire series of holes are successively punched in a template without movement of either the locating pin or the punch. An accurate setting of the locating 3,176,568 Patented Apr. 6, 1965 ice,

pin with respect to the punch is attained by means of a xed precision screw which carries thereon a threaded sleeve having Vernier markings on its circumference which match an index mark on the locator head.

The first hole punched in the template strip acts as a locator hole for the next punched hole and each succeeding hole is punched using the preceding punched hole as the locator hole. The rst hole is normally punched at the midpoint of the strip.

ln locating the locator pin, the microset 'head is moved longitudinally to a rough setting and then the threaded sleeve is located on the precision screw using the Vernier as a guide to a fine setting after which the threaded follower or clamp is brought into engagement with the micrometer head to bring it into abutment with the threaded sleeve.

Referring to the drawings, the main elements of the microset punch comprises a bed 20, a punch head 21, a longitudinal screw 22, a micrometer head 23, a scale 242-, and a strip or aligning guide 25.

The bed 20 has suitable legs 26 and a suitable platform 27 extending longitudinally of the machine. Upright standards 28 at the opposite ends have longitudinal openings Stl which receive the reduced diameter threaded ends 3l of the threaded portion of screw 22 of the microset and the threaded ends 31 are anchored to the uprights 28 by nuts 32. i

The screw 22 is a precision screw which will be lapped into the micrometer knurled threaded sleeves or nuts to be described.

The thread of the screw 22 receives the micrometer knurled threaded sleeve 33 riding the screw 22. The sleeve 33 has va micrometer ruling or scale 34 around its circumference, suitably subdivided into small fractions of a linear measure, which in the preferred design are increments of .0001 inch. The threaded screw 22 is preferably one of 20 or 40 threads per inch. It is evident that if there are 40 threads per inch, one complete revolution of knurled threaded sleeve 33 would move said element linearly .025 inch. If the threaded bar 22 is threaded 20 threads per inch, a complete rotationY of knurled threaded sleeve 33 would move said element linearly .050 inch.

A pin carrier 35 is slidably mounted on screw 22 with minimum clearance. A main shaft 36 extends longitudinally, suitably below the screw 22 and parallel thereto, and extends through the standards 28 with reduced diameter threaded ends 37 anchored by nuts 38. The pin carrier 35 has an index 40 which can be roughly set with respect to a longitudinal scale 41 which is mounted on strip guide 25 at the back of the bed 20. The strip guide 25 has a perfectly longitudinally aligned forward edge 43 parallel to main shaft 36 against which the edge 39 of the strip 39 to be punched is positioned to maintain perfect alignment of the punch holes 392. The main shaft aligns the pin carrier and keeps it a constant distance from strip guide edge 43.

The pin carrier 35 has an extension 44 beneath the bed which carries a pin 45 extending upward through slot 46 and having a head 47 of exact size of the holes 392 being punched in the strip 39. The head 47 is chamfered at 48 on the upper edge.

The pin carrier 35 at the opposite side where it surrounds the screw 22 is engaged by a back-up or clamping nut 5t) which is threaded on the screw 22.

The punch suitably has a body 5l which has an operating plunger chamber 52 and a throat 53 extending slightly deeper than the aligning edge 43 of the strip guide 25.

The plunger 54 has a head 55 which is engaged by a cam 56 on a cam shaft 57 journalled on the punch at 5S. The cam shaft is manually operated as by handle 60.

- The punch plunger rides in a suitable bushing l61 and is spring urged to retract by helical compression spring 62. The punch cooperates with a die 63 mounted in the lower portion of the punch body which is suitably countersunk underneath at 64 so as to free the punching.

In operation of the device of the invention, the micrometer threaded sleeve 33 and the clamping nut 50 are both backed off an adequate distance and the pin carrier 35 is adjusted until its index 40 is aligned with the desired increment as indicated by scale 41. Micrometer knurled threaded sleeve 33 is then brought forward and the proper setting to fractions of .0001 inch are obtained by aligning with index 65 on the pin carrier and clamping nut 50 is tightened against pin carrier 35. This biases the pin carrier 35 always in the same direction against the micrometer threaded sleeve so that any tolerance in the threads between the sleeves and the shaft is consistent since it is always read in the same direction.

The axis of the punch plunger 54 is now set a predetermined increment from the axis of the pin 45.

The pin carrier 35 remains locked in this position during the punching of a particular strip 39 or series of strips which have lthe same increments spacing between holes 392.

With an adequate length of strip, the strip is placed into the throat 53 of the punch from the right hand side and the end of the strip aligned with an index 65 for punching the rst hole and seated against the strip alignment guide 25 at the edge 43. Then` the iirstvanchor hole is punched. The strip is then turned end'for end upside down so that the same guide surface is against the strip guide 25 and the opposite end aligned with the index 66 and the second anchor hole punched. These anchor Aholes are intended to enable the strip to be suitablyrrxed,

or anchored, in an indexing device.

If this is a strip 39 yto be used as a control strip for indexing a step-and-repeat machine as in the above referred to application, then this strip is moved to the lextreme left index mark 67 or 67 and a rst indexing hole is punched. At the time the iirst indexing hole is punched, the strip will be deflected over the top of the pin 45;

The strip is then moved to the left until the rst indexing hole just punched seats itself over indexing pin 45 and a second index hole is punched. Succeeding index holes 392 to the right of the center hole on the indexing strip are punched by successively moving the strip to the left and engaging the strip over the pin 45 and then punching the next hole until all holes to the right of the center have been punched.

It should be understood that the index marks 67 and 67' correspond to a given length of control strip and that Ythese marks can be suitably placed for various strips.

The strip is then removed from the machine and turned end for end and bottom side up, keeping the same edge against the edge 43 of the guide strip 25. The first indexing hole is then engaged on pin 45 and all holes again to the right of center are punched one at a time, always 4 keeping the previously punched hole around the pin 45 when the next hole is punched.

It will thus be evident that the same longitudinal edge of the strip being punched is always used as a reference, and the same irst indexing hole is used as a reference in punching holes on both sides of it, and then each hole functions as a reference for punching the next hole so that there will be precise location of all control holes.

n view of my invention and disclosure, variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention Without copying the structure shown, and I, therefore, claim all such insofar as they fall within the reasonable spirit and scope of my claim.

{aving thus described my invention what I claim as new and desire to secure by Letters Patent is:

In a punch assembly for punching spaced holes in a strip of material having a longitudinally extending straight edge, a longitudinally extending base, a longitudinally extending reference edge on the base for engaging the strip straight edge, a punch head including a punch on the base, a longitudinally extending screw mounted on the base in a direction parallel to the reference edge, a carrier slidably supported on said screwy and having thereon means for engaging a given hole in the strip for positioning the strip against the straight edge with respect to the punch head, means for roughly positioning said carrier on said screw including indicator markings on the base and carrier, a rst threaded sleeve threadably engaging the longitudinal screw and positioned on one side of said carrier, a second threaded sleeve threadably engaging the longitudinal screw and positioned on the side of the carrier remote from the said irst sleeve, and markings on one of said sleeves for precisely indicating the position of said carrier with respect to said punch, whereby the carrier is precisely positioned and locked to the screw between the threaded sleeves, thus positioning the strip to be punched with respect to the punchhead.

References Cited by the Examiner UNITED STATES PATENTS 191,311 5/77 Choate 83--467 1,006,277 10/11 Richards 83-467 1,485,149 2/24 Renken 83-467 1,510,008 9/24 Lumb 83-467 1,755,468 4/30' Cheshire 83-468 1,763,869 6/30 Spiers 83-467 1,870,055 8/32 Kline 83-467 2,724,186 11/55 Lenart 33-165 2,801,472 8/57 Davidiak et al.

'3,152,505 10/64 Alldis 83-628 ANDREW R. JUHASZ, Primary Examiner.

HUNTER C. BOURNE, IR., Examiner.