BACKGROUND OF THE INVENTION
[0001] The present invention relates to punch press dyes, and particularly to means for
selecting groups of punches from an available supply of punches to selectively choose
the hole spacing to be punched.
[0002] Hole punching machines can be manually or electrically operated. A manual punching
machine is described, for example, in U.S. Patent 4,645,399. Electric punch machines
are described, for example, in U.S. Patents 3,153,966, 3,427,914 and 3,793,660. In
these machines, a series of pins which are carried by a pressure bar are adapted to
overlie individual punches and are thus selected for the desired hole pattern. However,
the pins must be set individually. A convenient selection of groups of punches for
a desired hole pattern is not disclosed.
SUMMARY OF THE INVENTION
[0003] It is an object of the present invention to provide a punch apparatus for allowing
selective operation of individual punches alone or in groups, selected from a group
of punches within a punch press to form a desired hole pattern. It is an object of
the present invention to provide a punch extending and retracting mechanism which
positively grips the selected punches to both instigate punching as well as retraction
of the punches from the punched paper. It is an object of the present invention to
provide a selection arrangement for punches which is easily switched between at least
two positions corresponding to two desired hole patterns for punching paper.
[0004] The objects are inventively achieved in providing a reciprocating selection plate
having notches registered with a plurality of punches. By shifting the selection plate,
a notch(es) engages a selected punch(es) whereas another notch(es) is moved to free
a selected punch(es). The punches have a shoulder for being engaged by the selection
plate and a C-clip arranged above the selection plate. The shoulder and C-clip together
form an annular groove for reception of the selection plate at the notch. The selection
plate is carried by the pressure bar and after engaging a selected punch(es) is reciprocated
toward the paper with the punch(es) captured in the notch(es) being depressed toward
the paper bar. After the punching operation is complete, the pressure bar is reversed,
the selection plate abutting against the C-clips to retract punches from the thus
punched paper.
[0005] At least one of the punches is spring biased away from the paper. By providing a
positive retraction of the punches as opposed to relying on individual punch spring
pressure alone, the spring(s) can be of a lesser spring force constant since they
need not be the primary driving force for retracting the punches through the punched
paper.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006]
Figure 1 is a perspective view of an electric punch machine of the present invention;
Figure 2 is a side view of the punch of Figure 1;
Figure 3 is a front view of the punch of Figure 1;
Figure 4 is a top view of the punch of Figure 1 with the cover removed for clarity;
Figure 5 is a partial sectional view taken generally alone line V-V of Figure 4; and
Figure 6 is an enlarged sectional view of a portion of the press shown in Figure 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0007] Figures 1-3 illustrate a paper punch 10 having a cover 12, a paper feed slot 14 for
vertical loading of paper, a punch selector lever 16 and a punch operating button
18. A side wall 20 is used to align the paper being punched. Additionally, ribs 22
can be used to align the paper being punched. The selector button 16 is reciprocal
in the direction A to select groups of punches. The operating button 18 controls a
switch (not shown) to instigate punching.
[0008] Figure 2 illustrates an adjustment knob 26 which is used to adjust an initial position
of the punches if they become stalled in extension.
[0009] Figure 4 illustrates a drive motor 30 of the punch press which has an axle 32 which
penetrates down beneath a chassis 34. Below the chassis 34 is mounted a plurality
of gears in a gear train which receive rotary force from the shaft 32. The complete
gear train which underlies the chassis 34 is not shown as such arrangement is known
in the art. However, extending up from below the chassis and as output shaft of the
gear train are two cam shafts 40, 42 which connect to offset rollers 44, 46 which
are captured between side flanges 48, 50 of a channel-shaped pressure bar 52. When
the shafts 40, 42 are rotated simultaneously and in the same rotational directions,
the rollers, 44, 46 being offset from the cam shafts 40, 42, reciprocate the drive
channel 52 in the direction B to either punch or retract.
[0010] In this embodiment there are four punches: a first punch 60, a second punch 62, a
third punch 64 and a fourth punch 66, respectively. The punches are elongate cylinders
which are journaled in a first block 70, a second block 72, a third block 74 and a
fourth block 76, respectively. The blocks provide paper receiving first slot 80, a
second slot 82, a third slot 84 and a fourth slot 86, respectively which are in registry
with the paper receiving slot 14. In Figure 4 the punches are shown in their retracted
position. When paper is to be punched, the punches 60, 62, 64 and 66 would bridge
the slots 80, 82, 84 and 86 to punch through the paper. In the shown embodiment, the
first and second punches 60, 62 are fixed to the side walls 48, 50 respectively by
a shoulder portion 60a of the punch 60 and a C-clip 60b on opposite sides of the side
wall 48, and by a shoulder portion 62a and a C-clip 62b on opposite sides of the side
wall 50. Therefore, according to this embodiment, these two punches would always reciprocate
in the direction B with the pressure bar 52.
[0011] The third and fourth punches 64, 66, however, are alternately selectable. When the
third punch 64 is selected then the second and third punches 62, 64 provide standard
two hole punching. The first punch being active but outside the edge of the fed paper.
When the fourth punch 66 is selected, then the punches 60, 62 and 66 provide standard
three hole punching. An electric switch 59 senses the complete retraction of the pressure
bar 52 and can then shut off the motor 30.
[0012] To select alternately the punch 64 or 66 a selector rail 100 is used. The selector
rail is of a generally L-shaped in cross section having a side wall 100a and a top
wall 100b with tabs 100c, 100d and interfit closely within the side walls 48, 50 of
the pressure bar 52. At one end of the pressure bar 52 an activator pin 102 is captured
by two C-clips 104, 106 onto the pressure bar 52 and within a slot 108 through the
side wall 48 and a slot 110 through the side wall 50. The pin penetrates the rail
100 through top aperture 112 through the side wall 100a and bottom aperture 114 through
the tab 100c. Thus, the activator pin can slide with the rail 100 through the slots
108, 110 of the pressure bar 52. The pin 102 is fixedly gripped by the selector lever
(not shown) 16 to be reciprocatable along the direction A by movement of the selector
lever.
[0013] At an opposite end of the rail 100, a guide pin 120 is captured by a top C-clip 122
and a bottom C-clip 124 to the pressure bar 52 and is arranged through apertures 130,
132 of the side wall 100a and tab 100d of the rail 100. This guide pin 120 acts as
a guide for reciprocal movement of the rail 100 within the pressure bar 52.
[0014] As shown in Figure 5, the cam shaft 42 is connected below the chassis 34 to a drive
gear 140 which is enmeshed with the gear train (not shown) which is gear connected
(not shown) to the motor shaft 32.
[0015] The rail 100 is shown which has a central cut-out 140 with inwardly facing notches
142, 144 which are slidable with the rail 100 to capture either the third punch 64
or the fourth punch 66 and release the respective other. When the rail 100 is slid
to the left, the notch 144 captures the fourth punch 66 and the notch 142 releases
the third punch 64.
[0016] The method of capturing the punches will be described with regard to Figure 6. The
third punch 64 is shown in a paper-punched condition being extended fully in the direction
B bridging the paper slot 84 where paper located therein would be punched. The fourth
punch 66 on the other hand has not been moved in the direction B and remains retracted
from the slot 86. The rail 100 has been slid to the right and the notch 142 has been
inserted between a shoulder 64a and a C-clip 64b of the third punch 64. The fourth
punch 66 also has a shoulder 66a and a C-clip 66b, but the notch 144 has been retracted
away from the fourth punch 66 so that the punch can escape through a large aperture
150 arranged in the side wall 48 of the pressure bar 52. An enlarged aperture 152
is provided for the third punch 64. Each of these punches provides a spring 154, 156
which assists in returning the punch and helps in effect to drive the pressure bar
52 to a retracted position.
[0017] The present invention provides for a motor retraction of the punches with the pressure
bar 52, and in particular, the selected punch such as the third punch 64 shown in
Figure 6, because the rail 100 positively captures the punch for movement in both
directions of B by abutting either the C-clip 64 or the shoulder 64a, depending on
direction of movement of the pressure bar 52. If the fourth punch 66 was selected,
the pressure bar 52 would translate the fourth punch 66 in both a punching and retraction
direction.
[0018] If, however, the motor did not return the punches to a completely retracted position
due, for example, an overload of paper causing the motor to stall and cut off too
soon, the adjuster 26 having pinion 26a is geared to the gear train (not shown) which
when manually turned will retract or extend the pressure bar 52 manually. This can
be undertaken to return the punches to the completely retracted position and thereby
disconnecting power to the drive motor 30 via the electric switch 59.
[0019] Although the present invention has been described with reference to a specific embodiment,
those of skill in the art will recognize that changes may be made thereto without
departing from the scope and spirit of the invention as set forth in the appended
claims.
[0020] The features disclosed in the foregoing description, in the claims and/or in the
accompanying drawings may, both separately and in any combination thereof, be material
for realising the invention in diverse forms thereof.
1. In a punch press having a plurality of punches arranged to punch holes through sheets,
the improvement comprising:
a pressure bar reciprocatable toward and away from sheets to be punched;
a first punch and a second punch arranged spaced along said pressure bar and movably
inserted through respective holes in the pressure bar, the first and second punch
having first and second groove formations respectively;
a selector rail mounted reciprocally with respect to said pressure bar and having
notches alignable with and facing said first and second groove formations of said
punches, reciprocation of said selector rail in a first direction engaging a first
notch to said first groove formation and disengaging said second notch from said second
groove formation, and reciprocating said selector rail in an opposite direction disengaging
said first notch from said first groove formation and engaging said second notch to
said second groove formation;
said selector rail movable with said pressure bar toward said paper to instigate punching
of said sheets; and
a respective one of said first and second punches, once disengaged from said selector
rail is disengaged from said pressure bar.
2. The improvement according to claim 1, wherein said selector rail is connected by a
pin to said pressure bar at an elongate slot thereof allowing said selector rail to
reciprocate with respect to said pressure bar; and
said pin connected to a selector lever to be engaged by a user.
3. The improvement according to claim 1, wherein said first groove formation comprises
a shoulder formed around a circumference of said first punch and a C-clip engaged
to said first punch around a circumference thereof spaced a discreet distance from
said shoulder.
4. The improvement according to claim 1, wherein said pressure bar comprises a channel
shape and said selector rail is guided for reciprocation within said channel shape.
5. The improvement according to claim 1, wherein said improvement further comprises a
third punch and a fourth punch, said first, second, third and fourth punches arranged
spaced apart along said pressure bar such that said second and third punches are spaced
according to a standard two hole punch, and said first, third and fourth punches are
arranged spaced corresponding to a standard three hole punch.
6. A punch press comprising:
a frame;
a cover overlying said frame;
first, second, third and fourth punches arranged within said cover and guided by said
frame;
a pressure bar mounted for reciprocal movement within said cover;
said cover having a paper receiving slot in registry with said first, second, third
and fourth punches;
a motor means to reciprocate said pressure bar toward and away from said slot;
said first and second punches fixedly connected to said pressure bar for reciprocation
therewith toward and away from said paper receiving slot;
said second and third punches alternately selectable to reciprocate with said pressure
bar toward and away from said paper receiving slot;
means for alternately selecting said third and fourth punches to reciprocate with
said pressure bar, said means mounted for movement with respect to said frame within
said cover, said means having a selector lever extending through said cover and operable
by a user to selectively activate one of the third and fourth punches.
7. The punch press according to claim 6, wherein said means for selecting comprises a
selector rail mounted reciprocally with respect to said pressure bar, and said third
and fourth punches are carried on said pressure bar in oversized apertures, and said
third and fourth punches comprise groove formations thereon for alternate engagement
by said selector rail when shifted between a first position and a second position
respectively.
8. The punch press according to claim 7, wherein said pressure bar comprises a channel-shaped
cross section and said selector rail is mounted reciprocally within said channel-shaped
cross section, said selector rail being guided by pins along said pressure bar and
having facing notch formations for alternately engaging said groove formations of
said third and fourth punches.
9. The punch press according to claim 6, wherein said groove formation of said third
punch comprises a shoulder portion formed on an outer circumference of said punch
and a C-clip surrounding said outer circumference of said punch and spaced a distance
from said shoulder portion.
10. A punch press comprising:
a frame;
a cover overlying said frame and having a paper receiving slot;
a plurality of punches arranged within said cover and guided by said frame;
a pressure bar mounted for reciprocal movement within said cover;
a means to reciprocate said pressure bar toward and away from said slot;
said plurality of punches arranged to include at least two hole patterns corresponding
to selected groups of punches;
means for selectively fixing said selected group of punches to said pressure bar for
reciprocal movement with said pressure bar to punch paper and be retracted thereafter,
said means mounted for reciprocal movement with respect to said frame within said
cover, said means having a selector lever extending through said cover and operable
by a user to select one of said two groups of punches.
11. The punch press according to claim 10, wherein said means for selecting comprises
a selector rail mounted reciprocally with respect to said pressure bar, and at least
one of said punches is carried on said pressure bar in an oversized aperture, and
includes a groove formation thereon for selective engagement by said selector rail
into said groove formation.
12. The punch press according to claim 11, wherein said pressure bar comprises a channel-shaped
cross section and said selector rail is mounted reciprocally within said channel-shaped
cross section, said selector rail being guided by pins along said pressure bar and
having a facing notch formation for selectively engaging said groove formation of
said at least one punch.
13. The punch press according to claim 12, wherein said at least one punch comprises a
spring biasing said punch against said frame to a retracted position from said slot.
14. The punch press according to claim 13, wherein said means to reciprocate said pressure
bar comprises:
an electric motor;
a cam shaft;
a roller connected eccentrically to said cam shaft and engaged to said pressure bar;
gear means for transferring rotary power from said electric motor to said cam shaft.