Projector for transparent file sheet

Projector comprising a housing, a support frame formed with a carrying surface for carrying a flexible file sheet in which transparent materials are arranged in the form of a matrix longitudinally and transversely, light source device arranged in the housing at one side of the support frame, projecting lens device arranged at the other side of the support frame, the support frame being mounted on the housing for a reciprocating movement in a first direction, the support frame being provided with guide rails for movably carrying the file sheet in a second direction perpendicular to the first direction. The projector further comprises retaining device for retaining the file sheet onto the carrying surface. The retaining device is mounted on the support frame for slidable or rotatable movement relative to the file sheet so that the transparent material can be easily changed in the file sheet without focus readjustment.

BACKGROUND OF THE INVENTION 
1. Field of the present invention 
This invention relates to a projector for projecting a image or object on a 
plate-like transparent material such as a photographic slide, a prepared 
specimen for microscopic observation file sheet onto a screen, 
specifically to a projector for a file sheet having a plurality of 
matrix-like arranged such transparent materials to be projected. 
1. Description of the prior art 
Japanese Patent Publication No. 55-47731 discloses a file sheet for a 
photographic slide or a prepared specimen in which a plurality of 
transparent materials are arranged in row and column respectively so that 
the transparent materials can be projected and observed as they are held 
on the file sheet. The file sheet can be conveniently bound in an album 
and the like as it is for facilitating a pigeonholing. 
The Japanese Patent Publication illustrates that the transparent material 
is projected by a projector on a screen as it is carried by the file 
sheet. Japanese Utility model application 58-10421 laid open to the public 
in 1983 and Japanese Patent Publication 58-21247 published in 1983 
disclose similar projectors thereto. The projector comprises a housing on 
which a support frame is disposed for carrying a file sheet. The support 
frame is provided with a carrying surface for carrying the file sheet 
thereon. The carrying surface is formed with a hole through which an image 
or information on the transparent material is projected. The file sheet is 
positioned on the carrying surface of the support frame resulting in 
positioning the transparent material. Thereafter, the projector is 
subjected to an focus adjustment with an optical system thereof. 
As a matter of fact, it should however be noted that the file sheet is 
difficult to be kept in a perfect plane condition when positioned. This 
means that the file sheet partially comes up to produce a partial offset 
from the carrying surface thereon when it is carried on the carrying 
surface. The partial offset of the file sheet affects the focusing 
condition of the optical system. Consequently, even after a focusing work 
is done with regard to a transparent material on a file sheet, a further 
focus adjustment may be necessitated for another transparent material on 
the same file sheet because of possible different distance to the carrying 
surface from each transparent material in the case where the other 
transparent material on the file sheet is being prepared for projection. 
The partial offset is caused by various factors. 
For example, the support frame is movably mounted on the housing in only a 
longitudinal direction wherein the file sheet is slid in a transverse 
direction to select a transparent material for projection in a relatively 
simple projector. Where the transparent material for selection is located 
at one end portion of the file sheet, the other end portion of the file 
sheet is extended over the support frame to hang down. This causes the 
partial offset around a transparent material positioned for projection. 
There has been known a projector provided with a click stop roller for 
being engaged with a cut out portion formed on a file sheet in order to 
position the file sheet with regard to the transverse direction. In this 
type of projector, the click stop roller urges the file sheet from the 
opposite side thereof in the longitudinal direction so that the partial 
offset occurs in intermediate portion of the file sheet. 
In order to prevent such partial offset, Japanese Utility Model Publication 
No. 58-29455 published in 1983 proposes a projector provided with a 
retaining device for retaining a subject on the carrying surface. The 
retaining device is provided with a retaining frame movably mounted on an 
outer cylinder of an optical projecting mechanism of the projector wherein 
the retaining frame is urged downwardly by means of a spring to retain a 
file sheet around a transparent material positioned for projection onto a 
carrying surface of a carrying frame. In this conventional retaining 
device, it is necessary to lift the retaining frame up against a resilient 
force of the spring so as to keep the frame away from the carrying surface 
for allowing the file sheet to be moved longitudinally and/or transversely 
in each time when a transparent material is replaced for projection. This 
makes an operation of the projector complicated. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide a projector 
for a file sheet having plural matrix like arranged transparent materials 
which can prevent a partial offset of the file sheet to facilitate a 
focusing work thereof. 
It is another object of the present invention to provide a retaining device 
which is easily handled for retaining a file sheet for a projector. 
According to the present invention, the above and the other objects of the 
invention can be accomplished by in a projector comprising a housing, a 
support frame formed with a carrying surface for carrying a flexible file 
sheet in which a plurality of transparent materials are arranged in the 
form of a matrix longitudinally and transversely and with an opening on 
the carrying surface for projecting the transparent material, light source 
means arranged in the housing at one side of the support frame, projecting 
lens means arranged at the other side of the support frame, the support 
frame being mounted on the housing for a reciprocating movement in a first 
direction, the support frame being provided with guide means for movably 
carrying the file sheet in a second direction perpendicular to the first 
direction, wherein the improvement comprises retaining means for retaining 
the file sheet onto the carrying surface, the retaining means being 
mounted on the support frame for slidable or rotatable movement relative 
to the file sheet. 
Specifically, a projector is provided with a support frame movable in one 
direction or a longitudinal direction of a housing. A retaining means is 
provided in the support frame for retaining the file sheet on a carrying 
surface. In the case where a movable stage which is movable in a 
transverse direction perpendicular to the one direction may be mounted on 
the support frame for carrying the file sheet on the carrying surface 
formed thereon, the retaining means is likewise provided on the support 
frame to be extended over the movable stage for thereby retaining the file 
sheet onto the carrying surface. The support frame is provided with guide 
means for movably carrying the movable stage in a transverse direction 
perpendicular to the one direction. In a preferred embodiment, the 
retaining means is constituted by a plate member of U-shaped configuration 
carried by the guide means like a cantilever and extending onto the 
carrying surface. In another embodiment, the retaining means is placed 
across a pair of guide rails arranged at opposite sides of the support 
frame. IN still another embodiment of the present invention, the retaining 
means is provided with a pair of resilient rods arranged across a pair of 
guide rails, rollers mounted on the respective rods for rotation so that 
the rollers are brought into engagement with an intermediate portion 
between transparent materials in the file sheet for urging the file sheet 
against the carrying surface of the support frame. 
In further embodiment of the present invention, a pair of rods extending in 
one direction of the support frame are removably provided with a roller 
frame on which a plurality of rollers are mounted for being engaged with 
the file sheet and urging it against the carrying surface. 
In yet further embodiment, the light source means is provided at a top 
portion with a support block having a rectangular opening wherein the 
support block is arranged in a manner that a top surface of the support 
block is extended horizontally over the carrying surface of the support 
frame. A transparent material in align with the light source means among 
transparent materials in the file sheet is urged by the retaining means 
against the top surface of the support block. 
According to the present invention, the file sheet is intervened between 
the retaining means and the carrying surface of the support frame or the 
movable stage. The retaining means urges the file sheet against the 
carrying surface so that an offset of the file sheet from the carrying 
surface ore a derivation in focused condition in an optical mechanism can 
be suppressed even when the file sheet is moved to replace the transparent 
material thereon for projection. 
In the case where the retaining means is constituted by a plate member, the 
file sheet can be slidably moved relative to the plate member so that the 
file sheet is moved transversely relative to the support frame for 
replacing the transparent material for projection as the plate member 
retains the file sheet onto the carrying surface. 
Where the retaining means is provided with roller means, it will be 
understood that the roller means rotates to facilitate the transverse 
movement of the file sheet. 
The retaining means can be constituted by a removable roller frame having 
roller means. In this case, where a plurality of the roller frames of 
different pitches in roller means are prepared, a single projector can be 
commonly used for a plurality of file sheets having different size, 
configuration and/or pitch of the transparent material. For instance, a 
photographic slide is different from a prepared specimen for microscopic 
observation in dimension so that frame portion of the file sheet is 
located at a different position from each other. Since the roller means 
should be moved on the frame portion of the file sheet other than the 
transparent material, it is impossible to find a roller position 
satisfactory for both the photographic slide and the prepared specimen. 
This problem can be solved by preparing one roller frame suitable for the 
photographic slide and another roller frame for the prepared specimen. The 
roller frames are selectively mounted on the projector in accordance with 
the file sheet for projection. 
The above and other objects and features of the present invention will 
become apparent from the following description in connection with the 
preferred embodiment taking reference with the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to the drawings, specifically to FIG. 1A through 1D, there is 
shown a first preferred embodiment of the present invention. 
A projector according to this embodiment comprises a main body of the 
projector or a projector housing 1 in which a light source device 
constituted by a light source and a condenser lens 2 is arranged. Although 
a cooling fan is also provided in the housing 1, these are already known 
to the public so that a detailed explanation thereto are omitted. 
The housing 1 is provided with an opening at a top surface thereof. The 
housing 1 is provided with a flange member 1a defining the opening of the 
housing 1. The flange member 1a carries at one end thereof a reflecting 
mirror 4 and an optical projecting mechanism having a projecting lens 5 
through an arm 6. The opening of the housing 1 is covered by a translucent 
sheet 3. The projecting lens 5 is connected with an adjusting screw 7 for 
focusing. The flange member 1 is provided with a pair of guide rails at 
opposite sides thereof. A file sheet support frame 8 is mounted on the 
housing 1 for a reciprocating movement along the rails 9. The support 
frame 8 is formed with a rectangular opening 12 elongated in a 
longitudinal direction shown by an arrow Y in FIG. 1A, in which the rails 
9 extend. The support frame 8 is also formed with a carrying surface 8a 
around the opening 12 for carrying a file sheet 17. The frame 8 is 
provided at opposite end portions with a pair of guide rails 10 and 11 
extending in parallel with each other in a transverse direction shown by 
an arrow X in FIG. 1A. The file sheet 17 of a configuration as shown in 
FIG. 1D is provided with a grid like frame portion 17a defining a 
plurality of rectangular frames 17b arranged in both the directions of X 
and Y like a matrix. Each frame 17b carries a transparent material 18. The 
file sheet 17 is placed on the frame 8 to be carried by the carrying 
surface of the frame 8 in a manner that front and rear edges of the file 
sheet 17 is brought into a slidable engagement with the guide rails 10 and 
11. A plate member 13 of a U-shaped configuration extending from the guide 
rail 10 along the opening 12 in the form of a cantilever. The plate member 
13 is positioned to surround the condenser lens 2 of the light source 
device. As shown in FIG. 1C, the plate member 13 extends substantially in 
parallel with the carrying surface 8a of the frame 8. The file sheet 17 is 
inserted between the plate member 13 and the carrying surface 8a. The 
frame portion 17a of the file sheet 17 is of a convex configuration in 
section of which top surface is engaged with the plate member 13 so that 
the plate member 13 urges the frame portion 17a of the file sheet 
downward. Thus, the file sheet 17 is urged against the carrying surface 8a 
of the support frame 8 to be retained. In order to change the transparent 
material 18 in the file sheet 17 for projection, the file sheet 17 can be 
moved by hand in the direction of the arrow X along the guide rails 10 and 
11 and/or the support frame 8 can be moved in the direction of the arrow Y 
along the guide rails 9. With this operation, an upper surface of the 
frame portion 17a of the file sheet 17 is slid along a lower surface of 
the plate member 13 so that the transparent material 18 on the file sheet 
17 can be kept from a damage. 
Referring to FIG. 2, there is shown second preferred embodiment of the 
present invention. This embodiment is substantially the same as the former 
embodiment except that a pair of retaining bars 14 are provided across the 
guide rails 10 and 11. The retaining bars 14 are arranged at opposite 
sides of the opening 12 so as to extend substantially in parallel with 
edge portions thereof. The retaining bars 14 urge the frame portion 17a of 
the file sheet 17 downward against the carrying surface 8a to retain the 
file sheet 17 between the bars 14 and the carrying surface of the frame 8 
as well as the former embodiment. 
Referring to FIG. 3, third preferred embodiment is shown. In this 
embodiment, a pair of resilient rods 16 are arranged at opposite sides of 
the opening 12 so as to extend substantially in parallel with edge 
portions thereof. a roller 15 is rotatably mounted on each of the rod 16 
at an intermediate portion thereof in the vicinity of a projecting area or 
the condenser lens 2. FIGS. 4A and 4B show an engagement of the roller 15 
and the file sheet 17. The frame portion 17a of the file sheet 17 is of a 
convex configuration in section forming slopes 17 on both sides as shown 
in FIG. 4B. The roller 15 is urged resiliently against the slope 17a by 
virtue of a resilient force of the resilient rod 16. Thus, the file sheet 
17 is retained on the carrying surface of the frame 8. In the case where 
the file sheet 17 is moved in the transverse direction for changing the 
transparent material 18 for projection, the roller 15 climbs over the 
convex portion of the frame portion 17a of the file sheet 17 to be engaged 
with a next slope 17c for thereby retaining a next frame 17b. By 
repetition of this operation, an objective transparent material 18 can be 
set for projection. As shown in FIG. 4A, each of the roller 15 is located 
on a peripheral portion 18a of the transparent material 18 other than an 
image area thereof in which an image is provided for projection. Thus, as 
the file sheet is moved for changing the transparent material 18 thereon, 
the roller 15 is kept from an interference with the image area of the 
transparent material 18. 
FIGS. 5A through 5B show forth embodiment of the present invention. 
According to this embodiment, a pair of crank shaped retaining rods 20 are 
mounted on the support frame 8. As shown in FIG. 5C, each rod 20 is 
rotatably mounted on the frame outside of the guide rails 10 and 11 with 
regard to the longitudinal direction. The guide rails 10 and 11 are formed 
with cutout portions 10a, 11a through which the rods 20 are urged against 
the file sheet 17 on the support frame 8. In order to urge the rod 20 
against the file sheet 17, there is provided a spring 21 between each of 
the rod 20 and the support frame 8. 
A roller frame 19 is provided across the pair of the rods 20. As shown in 
FIG. 5A, the roller frame 19 of a rectangular configuration is provided at 
four corners thereof with rollers 15 which are rotatable about shafts 15a 
extending in the longitudinal direction. The roller frame 19 is formed 
with V-shaped grooves 19a at opposite side ends as shown in FIG. 5B. The 
grooves 19a are brought into engagement with the rods 20 respectively so 
that the roller frame 19 is carried by the pair of rods 20. Thus, the 
roller 15 on the roller frame 19 is urged against the file sheet 17 on the 
support frame 8 by virtue of the rod 20 to thereby urge the file sheet 17 
against the carrying surface 8a of the frame 8. 
It is necessary to change a position of the roller 15 since a pitch of the 
frame portion 17a changes between a photographic slide and a prepared 
specimen for microscopic observation. According to the present invention, 
preferably, the roller frames 19 having various pitches of a frame portion 
17a are prepared to be selectively mounted on the projector. 
Referring to FIG. 6A through 6C, there is shown a still another embodiment 
of the present invention. In this embodiment, the projector is a support 
frame 8A mounted on the housing 1 for a longitudinal, and a movable stage 
22 mounted on the support frame 8A for a transverse direction. The support 
frame 8A is moved in the longitudinal direction along the rail 9A. The 
support frame 8a is provided at longitudinally opposite sides thereof with 
a pair of guide rails 10A, 11A extending transversely. The movable stage 
22 can be moved transversely along the guide rails 10A, 11A. 
The file sheet 17 is fixedly carried on the movable stage 22. In order to 
restrict a transverse movement of the file sheet 17, the movable stage 22 
is formed with rim portions 22A at transversely opposite sides thereof. 
The support frame 8A is provided with a pair of crankshaped rods 23 
rotatably mounted on the support frame 8A outside of the guide rails 10A, 
11A at opposite end portions thereof. Each of the rod 23 carries a roller 
15A at an intermediate portion thereof. The rod 23 is extended over the 
guide rails 10A, 11A and the file sheet 17. As shown in FIG. 6C, there is 
provided a spring 24 between the support frame 8A and the rod 23 for 
urging the rod against the file sheet 17 on the stage 22. Therefore, the 
roller 15A on the rod 23 is urged against the file sheet 17 by virtue of 
the spring. In order to keep the roller 15A away from the file sheet 17 
upwardly, a control rod 25 formed with a cam portion 25a is provided as 
shown in FIG. 6C. As the control rod 25 is rotated to bring the roller 15A 
to a position shown by a reference 15B in FIG. 6C, the stage 22 can be 
inserted under the roller 15A to be mounted on the frame 8A. 
Referring to FIG. 7A through 7D, there is shown a modification of the 
embodiment explained in connection with FIGS. 3 and 4. 
In this embodiment, the same numerals are employed for the same elements. 
A pair of guide rails 10A, and 11A disposed away from each other in the 
longitudinal direction are separated at intermediate positions to define 
blank portions 10A' and 11A' respectively. There are provided a pair of 
crank-shaped rods 30 movable into the blank portions 10A' and 11A'. The 
rods 30 extend longitudinally. Each of the rod 30 is formed with cranked 
portions at opposite ends and pivotally mounted on outer side of the guide 
rails 10A and 11A Each of the rod 30 is urged toward the condenser lens 2 
by virtue of a spring 32 as shown in FIG. 7A. A plurality of rollers 34 
are rotatably mounted on the rod 30 in a spaced relationship with each 
other. As best shown in FIG. 7B, the rollers are positioned to be engaged 
with the transparent material 18 at a rim portion other than the image 
area. Two of the rollers 34 adjacent to each other engaged with rim 
portions of two transparent materials adjacent to each other respectively 
are connected by a reduced shaft portion 36. An outermost roller 34 
engaged with a rim portion of outermost transparent material 18 is 
provided independently. 
As best shown in FIG. 7D, a support block 38 (of a rectangular 
configuration of the illustrated embodiment) having an opening 37 
corresponding to a top opening 12 of a condenser lens frame 2A is mounted 
on a top portion of the frame 2A. A top surface of the support block 38 is 
located above the carrying surface 8a of the support frame 8 (preferably 
by approximately 1-2 mm). 
With this structure, when the file sheet 17 is introduced between the rod 
30 and the carrying surface 8a of the support frame 8, each of the 
transparent material 18 on a longitudinal row in the file sheet 17 
retained by a positioning blade 17d is engaged with the rollers 34 at the 
four corners thereof. It will be understood from FIG. 7D that the 
transparent material 18 in align with the support block 38 on the 
condenser lens frame 2A is resiliently urged against the support block. As 
a result, the transparent material can be surely maintained at a 
horizontal attitude even when the file sheet 17 is moved longitudinally 
and transversely. 
Referring to FIG. 8, the illustrated embodiment is provided with a 
projection lens mechanism comprising a projection lens 40 and a CCD 42 so 
that an image on the transparent material can be projected on a TV 
screen(not shown). In this embodiment, the transparent material 18 on the 
file sheet is retained by the similar structure to the embodiment 
explained in connection with FIGS. 7A through 7D. 
While the invention has been specifically described in connection with 
preferred embodiments thereof, it will be understood by those skilled in 
the art that the foregoing and other changes or modifications in form and 
details can be made therein without departing from the spirit and scope of 
the invention.