Film punch

A base defining an upwardly facing sheet supporting surface and an elongated support member is mounted on the base and projects upwardly from the sheet support surface. The support member includes spacer structure spacing portions of the support member from the base to define an open slot between the base and the spaced portions of the support member. A pair of aligned support blocks are supported from the support member above the opposite end portions of the slot and an elongated head extends between and is removably journaled from the support blocks. The portions of the support member spaced above the base define upstanding sleeve bores therein normal and opening into the slot and bearing sleeves are mounted in the sleeve bores and have elongated punch members reciprocately disposed therein. The base defines die bores below the slot and opening into the latter aligned with the sleeve bores. Die sleeves are disposed in the die bores. The head includes crank arm portions spaced therealong registrable with the sleeve bores. Elongated connecting link structures are pivotally connected at one set of corresponding ends to the crank arm portions and at the other set of ends to the upper ends of the punch members for shifting the punch members from positions within the sleeves above the slot to positions with the lower ends thereof projecting through the slot and into the die bores upon oscillation of the head.

BACKGROUND OF THE INVENTION 
Sheet punching devices have been heretofore provided, such as those 
disclosed in U.S. Pat. Nos. 3,164,050, 3,196,725, 3,385,152, 3,469,486, 
3,492,901 and 3,921,487. However, these previously known sheet punching 
devices are not, for the most part, constructed in a manner to provide 
precision punching with a minimum of effort and by structure designed 
specifically to offer ease of operation, extended periods of usage with 
only minimum maintenance and ease of repair, when necessary. Accordingly, 
a need exists for an improved sheet punching apparatus which may be 
utilized efficiently and will enjoy an extended lifetime of usage with 
minimum maintenance requirements and ease of repair, when necessary. 
BRIEF DESCRIPTION OF THE INVENTION 
The sheet punching apparatus of the instant invention includes removal 
punch member sleeves and die sleeves as well as removable punches and 
dies. Further, the sheet punching apparatus includes structural features 
which offer extended life expectancy with little maintenance requirements. 
In addition, the sheet punching apparatus is constructed in a manner 
whereby sheets may be accurately and cleanly punched with little effort. 
The main object of this invention is to provide a sheet punching apparatus 
capable of accurately and efficiently punching sheet material. 
Yet another object of this invention is to provide a sheet punching 
apparatus including actuator structure therefor offering considerable 
mechanical advantage during sheet punching operations. 
A further object of this invention is to provide a sheet punching apparatus 
which will offer an extended operational lifetime with little maintenance 
requirements. 
Still another important object of this invention is to provide a sheet 
punching apparatus constructed in a manner whereby repairs thereto, when 
necessary, may be readily made. 
A final object of this invention to be specifically enumerated herein is to 
provide a sheet punching apparatus in accordance with the preceding 
objects and which will conform to conventional forms of manufacture, be of 
simple construction and easy to use as to provide a device that will be 
economically feasible, long lasting and relatively trouble free in 
operation. 
These, together with other objects and advantages which will become 
subsequently apparent, reside in the details of construction and operation 
as more fully hereinafter described and claimed, reference being had to 
the accompanying drawings forming a part hereof, wherein like numerals 
refer to like parts throughout.

DETAILED DESCRIPTION OF THE INVENTION 
Referring now more specifically to the drawings, the numeral 10 generally 
designates the sheet punching apparatus of the instant invention. The 
apparatus 10 includes a horizontal base 12 including an upper support 
surface 14. An elongated support member 16 is provided and rests upon the 
rear marginal portion of the upper surface 14. The rear portion of the 
underside of the support member 16 includes depending spacer portions 18 
which support the front marginal edge portion 20 above the upper surface 
14 to define a horizontally opening elongated slot extending transversely 
of the base 12 and opening forwardly thereacross toward the forward edge 
22 of the base 12. 
The forward corners of the base 12 include downwardly opening blind bores 
24 for receiving upwardly projecting indexing pins supported from the 
surface 26 upon which the base 12 is disposed and the rear corners of the 
base 12 include vertical bores 28 formed therethrough including lower end 
counterbores 30. The opposite ends of support member 16 have vertical 
bores 32 formed therein registered with the bores 28 and a pair of support 
blocks 34 having downwardly opening threaded blind bores 36 formed therein 
are supported on top of the opposite ends of the support member 16 with 
the bores 34 registered with the bores 32. Elongated headed bolts 38 are 
passed upwardly thrugh the bores 28 and 32 and are threadedly engaged in 
the bores 36 in order to removably support the support member 16 from the 
base 12 and the support blocks 34 from the opposite ends of the support 
member 16, the heads of the bolts 38 being seated in the counterbores 30. 
The support blocks 34 include horizontally registered bores 40 formed 
therethrough, and the bores 40 have bearing sleeves 42 mounted therein. 
The remote ends of a pair of stub shafts 44 are journaled in the bearing 
sleeve 42 and the confronting faces of the support blocks 34 have bores 46 
formed therein in which a pair of corresponding angulated ends 48 of a 
pair of coiled torsion springs 50 are removably seated. 
The coiled springs 50 are disposed about the stub shafts 44 and the latter 
are supported from and project outwardly from the opposite ends of an 
elongated head 54. The head 54 includes blind bores 56 on its opposite 
ends corresponding to the blind bores 46 and in which second angulated 
ends 58 of the coiled springs 50 are removably anchored. 
The head 54 includes crank arm portions 60 supported from the mid and 
opposite end portions thereof and the arm portions 60 project outwardly 
from the head 54 generally radially of the concentric center axes of the 
stub shafts 44. 
The support member 16 includes a plurality of mid and opposite end plunger 
sleeve bores 62 formed therethrough opening downwardly into the slot 20 
and the bores 62 have plunger bearing sleeves 64 removably mounted 
therein. Further, the base 12 includes a plurality of die bores 66 formed 
therein coaxial with the bores 62 and the die bores 66 include upper end 
counterbores 68 in which die sleeves 70 are removably seated. 
A plurality of elongated punch members 72 are reciprocal in the sleeves 64 
and include headed upper end portions 76. A plurality of connecting link 
assemblies referred to by the reference numerals 78 connect the arm 
portions 60 to the corresponding headed upper end portion 76. The 
connecting link assembly 78 each include a pair of side links 80 and the 
upper ends of each pair of side links 80 are pivotally anchored to 
opposite side portions of the corresponding arm portions 60 by means of a 
removable pivot fastener 82. The lower ends of each pair of links 80 are 
pivotally connected to the corresponding headed upper end portions 76 by a 
pivot fastener 84. 
The central portion of the head 54 includes a threaded bore 86 in which one 
end of an operating arm 88 is threadedly engaged, the other end 90 of the 
operating arm 88 being threaded and having an operating knob 92 threadedly 
mounted thereon. 
From a comparison of FIGS. 4 and 6 of the drawings, it may be seen that 
when the operating arm 86 is in the upper position thereof illustrated in 
phantom lines in FIG. 1 of the drawings and in solid lines in FIG. 6 of 
the drawings, the connecting link assemblies 78 raise the punch members 72 
to positions with there lower ends spaced slightly above the slot 20. 
Further, when the operating arm 88 is in the lower position thereof 
illustrated in FIG. 4, the punch members 72 have their lower ends 
displaced downwardly through the slot 20 and into the upper ends of the 
die sleeves 70. Also, it will be noted that when the operating arm 88 is 
in the lower limit position thereof illustrated in FIG. 4 of the drawings, 
the connecting link assemblies 78 are substantially vertically disposed. 
With attention now invited more specifically to FIGS. 4 and 6 of the 
drawings, it may be seen that the center portion of the support member 16 
supports an abutment block 94 therefrom through the utilization of 
additional bolts 38 in the same manner in which the blocks 34 are 
supported from the opposite ends of the support member 16. Further, the 
abutment block 94 includes a forward face 96 abuttingly engageable by the 
lower portion of the head 54 to define the lower limit of swinging 
movement of the operating arm 88 as illustrated in solid lines in FIG. 4. 
Also, the abutment block 94 includes an upper inclined surface 98 
abuttingly engageable by the head 54 to limit upward swingly movement of 
the operating arm 88 to the phantom line position thereof illustrated in 
FIG. 4. 
Inasmuch as the sleeves 64 and 70 may be readily replaced and the punch 
members 72 as well as the connecting link assemblies 78 may be readily 
replaced, it is deemed readily apparent that the major operating 
components of the sheet punching apparatus 10 may be replaced, when 
necessary. Further, the sleeve 42 may also be replaced, if desired. 
The foregoing is considered as illustrative only of the principles of the 
invention. Further, since numerous modifications and changes will readily 
occur to those skilled in the art, it is not desired to limit the 
invention to the exact construction and operation shown and described, and 
accordingly all suitable modifications and equivalents may be resorted to, 
falling within the scope of the invention.