Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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BACKGROUND OF THE INVENTION
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1. FIELD OF THE INVENTION
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This invention relates generally to the photocomposing
industry and more particularly, to font clips adapted to
releasably secure a font to a drum of a photocomposing machine.
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2. DESCRIPTION OF THE PRIOR ART
Photocomposing machines are well known in the prior
art and include various different configurations. These have
included machines which utilize font plates in the form of
spinning discs, plates using rectangular columns and rows
; and different systems have been provided which either move the
font plate or alternatively, transpose the image from the font
to the desired position.
More recently, the photocomposing machines which have
been used are as shown in United States patent number 3,738,236
granted to Grube et al on June 12, 1973.
These machines include a moveable character drum and
20 an optical system which focuses a preselected character from
a font or font element unto a roll of sensitized material.
A flexible font has a series of characters (which may
include numerals, letters or other symbols) arranged on its
face and a retaining means which is secured to the font and which
is adapted to interact with means carried on the drum to secure
the font to the character drum. The means carried by the drum
which interacts with the retaining means on the font comprises,
in one embodiment, a pair of hooks extending from the drum which
hook unto one side of the retaining means on the font and a
pair of vertically aligned protrusions which are displaced around
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1 the drum from the pair of hooks approximately the same aistance
as the length of the font.
In another embodiment, the pair of protrusions may be
displaced from the pair of hooks and, with this embodiment, project
through the font to be contacted by the retaining means which is
carried on the font in a coxresponding position. The font
itself may extend beyond the means on the drum if desired.
Various means have been tried to releasably secure
the font to the drum. As shown in Grube et al, a pair of
retaining means are secured to the opposite peripheral widths
of the font. One retaining means is a flat, rectangular bar
about which the pair of hooks from the drum are secured
through corresponding apertures in the font.
On the opposite side of the font, a second but shorter
rectangular bar is provided with spring means extending from
each end of the bar. Two small protrusions protrude from the
drum through apertures in the font and the spring means, by
friction, holds the font to the drum.
Unfortunately, these clips have drawbacks which make
them unsuitable for long and continuous use. Prior to the
present invention, it was impossible to obtain clips which
held the font to the drum without fatigue and yet, were
inexpensive to manufacture and easy to use.
The particular drawbacks of the devices of the prior
art include the problem of insufficient resiliency during
use. On many occasions, because of this lack of resiliency,
the clips would rip the rivets right through the font. Wire
fatigue has always been a problem. A further problem is that
the drum rotates very quickly with back and forth rotations
and unless the font is secured properly, the font ~a~ pop off
the face of the drum. If this occurs, the font is usually
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1 destroyed and other fonts on the drum may be damaged or
; destroyed. The machine must then be stopped and disassembled
and a new font or fonts placed on the drum. This stoppage
reduces the amount of time the machine is operational thus
reducing the efficiency of the system.
SUMMARY OF THE INVENTION
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Accordingly, the present invention provides novel
retaining means adapted to releasably secure a font to a
rotatable character drum. 'l'he means comprises a first clip
and a second clip, which, in combination with the securing
means on the drum itself, holds the font in correct alignment
on the face of the drum with sufficient tensile strength to
seat the font correctly yet rigidly on the drum.
To this end, in one of its aspects, the invention
provides retaining means adapted to releasably secure a font
to a rotatable character drum, said retaining means comprising
a first clip and a second clip, each clip adapted to be secured
` to a respective side edge of said font, said first clip having
flattened peripheral end portions, and said second clip having
flexible V-shaped end portions, said end portions of said first
and second clips being adapted to releasably secure said
font to said drum.
In another of its aspects, the invention further
provides a retainer means for use with a font in a photocomposing
machine having a rotatable drum, said font having a plurality
of characters thereon arranged in a predetermined sequence
and position, a plurality of alignment apertures, and a series
of timing marks on one edge (length), said drum carrying a
pair of hooks adapted to project through a first pair of
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1 corresponding apertures in said font and a pair of protrusions
: . adapted to protrude through said pair of corresponding
apertures in said font, said first pair of apertures positioned
near one width edge of said font and said second pair of
apertures positioned near the opposite width edge of said
font, retaining means secured to said font and adapted to
releasably secure said font to said drum, said retaining means
comprising a first clip and a second clip, said first clip
secured to said font and having flattened end portions which
engage said pair of hooks, said second clip having flexible
V-shaped end portions which engage said pair of protrusions
which protrude through said second pair of apertures and
secure said font to said drum.
In further of its aspects, the invention provides
a photocomposing machine which includes a rotatable drum, a
. font having characters thereon and releasably secured to
said drum, means for projecting the characters on said font
to a recording medium, said font having a plurality of
- characters thereon arranged in a predetermined sequence and
position, a plurality of alignment apertures, and a series
of timing marks on one edge (length), said drum carrying a
: pair of hooks adapted-to project through a first pair of
corresponding apertures in said font and a pair of protrusions
adapted to protrude through said pair of corresponding
apertures in said font, said first pair of apertures positioned
`!! near one width.edge of said font and said second pair of
apertures positioned near the opposite width edge of said
font, retaining means secured to said font and adapted to
releasably secure said font to said drum, said retaining
means comprising a first clip and a second clip, said first
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1 clip secured to said font and having flattened end portions which
engage said pair of hooks, said second clip having flexible V-
shaped end portions which engage said pair of protrusions which
protrude through said second pair of apertures and secure said
font to said drum.
BRIEF DESCRIPTION OF THE DRAWINGS
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FIGURE 1 is a front view of said font clips.
FIGURE 2 is a perspective view of said font clips.
FIGURE 3 is a front view of said clips secured to said font.
FIGURE 4 is a perspective view of said font and clips
secured to a drum.
FIGURE 5 is a top end view showing the engagement between
the protrusions and the second clip when the font and clips are
secured to the drum.
FIGURE 6 is a top view showing one end of the second clip
in engagement with the protrusions on the drum.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The font clips of the present invention provide notable
improvements over the prior art and they combine basic simplicit~
- 20 with modern technology and materials. In particular, these clips
have the ability to overcome the diverse differences in the manu-
facturer's tolerances of the retaining points on the actual charac-
ter drum. Sufficient tensile strength is provided to seat the font
correctly while maintaining sufficient rigidity on the drum.
The clips are easily mounted and removed and are made of
a material of sufficient durability to overcome a primary fault in
the prior art clips; that is, the steel spring or resilient means
was prone to lose its tensile strength thus reducing its retention
capabilities.
The locking means incorporated into the present de~ice
overcomes any variances in the horizontal and vertical locating
points on the drum and the clips are sufficiently light so as not
to cause a weight imbalance when the fonts are mounted.
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1 Referring now to figure 1 of the appended drawings,
there i5 shown a pair of font clips of the present invention
(shown in perspective view in figure 2).
The retaining means (or clips) of the present invention
comprises a first clip 10 and a second clip 12. The first clip
10 includes an elongated, substantially rectangular base 14 and
an elevated central portion 16. Base 14 has a pair of flat,
peripheral portions 18, 20, one flat portion at each end, the
purpose of which will be explained hereinafter.
Elevated central portion 16 of the clip 10 is shown ~-
with a central recessed portion 22. This recessed portion is
not an essential element of the invention but in the preferred
embodiment, has been introduced to reduce the weight of the clip
10 and the material required for its production. Rivet holes
24, 26-are provided to secure the clip to the font. ~Any means
may be used to secure the font clips to the font but it has
beèn found that rivetting provides a secure, quick and inexpensive
method to accomplish this.
In the figures, the clip 10 is shown as having
indented portions 28, 30. These indentions are provided to
reduce the weight of the clip and the material required to
manufacture it. These indentions may be omitted without
deviating from the scope of the present invention.
The second clip 12 comprises an elongated body of
approximately the same length as the first clip 10 and of
approximately the same height as the central portion of the clip
10. Clip 12 may be of marginally greater length than clip 10
if desired.
Each end of clip 12 comprises a V-shaped portion 32,
34 with the base of the "V" directed inwardly and normal to
the longitudinal axis of the clip 12 and a thin, peripheral
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1 end 36, 38 colinear with the longitudinal axis of the clip 12.
A central, recessed portion 40 is also provided which, like
recessed portion 22 in clip 10, reduces the weight of the
clip. Rivet holes 42, 44 are also provided to secure the clip
to the font as will be explained hereinafter.
Referring now to figure 3, there is shown a film font
46 with clips 10 and 12 secured thereto. Font 46 is a photo-
graphic negative with a series of characters (which may include
numerals, letters or other symbols) arranged in a predetermined
order and position. The font usually has an opaque background
with transparent characters thereon and may be of any desired
and well-known series of characters.
The font 46 carries a series of apertures on its
surface which aid in securing it to the drum and aligning it in
the desired position.
On each side of the font, there are disposed a pair
of apertures 48, 50 and 52, 54 which are used in conjunction
with the clips 10, 12 to secure the font to the drum. Other
- apertures 56 may be found on the face of the font to align
it in the desired position on the drum.
The clips may be secured to the font by any well-
known means. An example of this means is the use of rivets
which are secured through rivet holes 42, 44 in clip 12
and holes 24, 26 in clip 10 thereby securing the clips to
the font in the desired position.
Referring now to figure 4, there is shown the font
- 46 (with clips attached) mounted on a drum 58. In order to
mount the font 46 on the drum 58, hooks 60, 62 are provided
on the drum which correspond to apertures 52, 54. The hooks
are placed through the apertures and over the flat end portions
18, 20 of the clip 10.
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The position of the font is then adjusted until the
alignment apertures 56 are secured to the Various alignment
protrusions on the face of the drum.
The opposite end of the font 46 is then secured to
the drum. Protrusions 64, 66 are provided which extend through
apertures 48, 50 in the font and the position of the protrusions
is such that the inner surfaces of the ends 36, 38 of clip 12
are forced marginally outwardly and are held in tension in
contact with the protrusions 64, 66. The particular design
and shape of the clip 12 provides the necessary resiliency
for ends 36, 38 to flex outwardly and secure that end of the
font 46 in contact with the protrusions 64, 66.
Thus, the font is releasably secured to the surface
of the drum in a quick and efficient manner.
The clips of the present invention may be manufactured
of any material which is lightweight and durable, and provides
the necessary resiliency and flexibility. The present inventors
- have found that acetal polymer fulfills these requirements and
has proven guite inexpensive.
Acetal polymer is a crystalline polymer based on
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trioxane and offers an excellent balance of predictable
engineering properties. It is strong, stiff, tough and of
- sufficient hardness to be particularly suitable for the present
application; either as the homopolymer or as a copolymer. The
natural copolymer is translucent to opaque and may be coloured
at very low costs.
The clips of acetal polymer may be manufactured by
using standard types of injection molding equipment and the
melt temperature may vary from 360 to 450F with no sacrifice
in part strength. After forming, the clips can be finished
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1 by a variety of finishing operations including annealing,
adhesion and fastening, machining and decorating, if desired.
Clips manufactured of acetal polymer possess high
strength and rigidity, excellent frictional properties and
outstanding resistance to fatigue. Thus, one of the serious
drawbacks of the clips of the prior art, namely, fatigue,
has been successfully overcome. Also, the clips of the present
invention show excellent tensile and flexural properties, making
them particularly suitable for the present applicat~on.
With the clips of the prior art, one of the problems
which has not been overcome is that the clips will release
from the drum during usage. As noted hereinbefore, the drum 58
rotates at a great rate of speed thereby tending to "throw off"
the font from the face of the drum. The applicant has found that
the clips 10 and 12 of the present invention securely hold the
font to the drum and do not suffer from fatigue during use.
For an explanation of how the clips hold the font to
~- the drum, reference is now made to Figures 5 and 6 of the
drawings. To secure the font to the drum, one end of the font is
placed on the drum so that the hooks 60 and 62 may be inserted
through apertures 52, 54 and over the flat end portions 18, 20
: of the clip 10. The Eosition of the font is then adjusted until
the alignment apertures 56 are secured to the alignment
protrusions on the face of the drum as explained hereinbefore.
Protrusions 64 are usually in the form of balls and
interact with the inner surfaces 37, 39 of the ends 36, 38 of the
clips 12. As shown in Figure 5, surface 39 has, in the preferred
embodiment, a slope of about 30 whereas the opposite surface 43
may have a slope of about 2. (The slope of surface 39 is not
restricted to an angle of 30 but may have any slope greater than
50).
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1 tSurfaces 37, 39 and 41, 43 are identical although
at opposite ends of the clip 12). When the font is to be placed
on the drum, the end 38 of clip 12 is distorted manually from
the position shown in dotted lines to the position indicated in
solid lines in Figure 5. When released, the clip assumes the
position shown in the l'chain-dot" line providing contact at the
point 35 with the protrusion 64.
If the pro~rusions 64 were not present, the clip,
because of its resilient character, would assume its normal
position shown in dotted lines. This is shown in top view of
Figure 6 of the drawings. Contact point 35 occurs on the sloping
; surface 39 of the end 38 of the clip 12.
It is thought that the sloping surface on one end of
the clip, in conjunction with the ball or protrusion, creates
a downward and inward pressure which forces the clip towards the
base of the ball thereby tending to hold the clip in contact
with the ball when the drum is rotated.
The V-shaped portions 32, 34 on the clip 12 provide
resiliency to the clip and distribute the bending or distorting
20 force applied to the clip when placed on the protrusions, over
the entire length of the body to prevent any overstressing of
the body. Contrary to the devices of the prior art, the clip is
hèld securely to the protrusion during rotation of the drum,
which in fact, causes the clip to be held more securely to the
drum rather than tending to throw the clip off the drum as
experienced with the prior art devices.
The clips themselves do not extend the full height of
- the font. As shown in Figure 3, one end of the clips is aligned
with an edge ~of the font but the opposite end of the clips
terminates at the edge of the alignment apertures 56. Thus, the
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1 clips do not interfere with timing marks 68 on the font 46.
Although the disclosure describes and illustrates a
preferred embodiment of the invention, it is to be understood
the invention is not restricted to this particular embodiment.
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