Motion picture camera with variable focal length lens

A motion picture camera with variable focal length lens wherein the zooming collar and the distance selecting or focusing collar on the lens barrel are rotatable to neutral positions by an actuating member which is movable at right angles to or in parallelism with the optical axis of the lens. In such neutral positions of the collars, the focal length of the lens is satisfactory for the making of exposures in daylight or artificial light, and the distance setting corresponds to a distance of 4 to 6 meters to thus guarantee an acceptable depth of field for exposures of subjects located anywhere between closeup and infinity. The actuating member can further close a master switch to allow for starting of the camera motor in immediate response to depression of the release trigger.

BACKGROUND OF THE INVENTION 
The present invention relates to photographic apparatus in general, and 
more particularly to improvements in photographic apparatus which are 
provided with variable focal length (zoom) lenses Still more particularly, 
the invention relates to improvements in motion picture cameras which are 
equipped with a plurality of adjusting elements including means for 
varying the focal length of the lens and means for focusing the lens for a 
given distance from the subject. 
Photographic apparatus which embody the above outlined features can be 
readily manipulated by skilled photographers. However, if a photographic 
apparatus having a zoom lens is to be used by several persons, for example 
by several members of a family, one or more persons are likely to be 
incapable of properly manipulating one or more adjusing elements whose 
manipulation is familiar to the other person or persons. Thus, the husband 
and/or the wife might not encounter any problems in connection with the 
manipulation of a motion picture camera which is equipped with a zoom lens 
but the child or children might not be familiar with the purpose and/or 
best mode of adjusting the zoom lens under different circumstances. This 
can result in the making of unsatisfactory exposures or is likely to deter 
one or more members of the family from using the camera. By way of 
example, a mother is often confronted with a situation where she could 
make exceptional shots of her children but for the fact that the motion 
picture camera which can be readily manipulated by the father is too 
complex for proper manipulation by the mother. 
OBJECTS AND SUMMARY OF THE INVENTION 
An object of the invention is to provide a photographic apparatus, 
particularly a motion picture camera having a zoom lens, with novel and 
improved means for moving one or more adjusting elements (such as a collar 
which can be rotated on the barrel of the zoom lens to change the focal 
length of the lens, a collar which can be rotated on the barrel to focus 
the image of a subject on the foremost unexposed film frame and/or a 
master switch which must be closed if the camera motor is to be started in 
response to depression of the release) to one or more predetermined 
positions in which the manipulation of the camera is simplified without 
unduly affecting the quality of exposures. 
Another object of the invention is to provide a motion picture camera 
having a zoom lens with novel and improved means for automatically moving 
the adjusting elements for focal length and focusing to predetermined 
positions in response to depression, pulling, pushing or pivoting of a 
single actuating member. 
A further object of the invention is to provide a photographic apparatus 
with simple, compact and inexpensive means for selecting the complexity of 
manipulation of the apparatus during the making of exposures in daylight 
and/or artificial light. 
An additional object of the invention is to provide a novel and improved 
motion picture camera whose versatility is just as satisfactory as the 
versatility of other advanced motion picture cameras with zoom lenses but 
which can be rapidly converted into a camera suitable for manipulation by 
novices or unskilled photographers while at the same time permitting such 
novices or unskilled photographers to make satisfactory exposures in 
daylight or artificial light. 
A further object of the invention is to provide novel and improved means 
for adjusting the focal length of the lens and/or for focusing the images 
of subjects in a motion picture camera which is equipped with a variable 
focal length lens. 
An ancillary object of the invention is to provide a motion picture camera, 
particularly a camera for use with 8-millimeter film, wherein the 
installation of means for moving one, two or more adjusting elements to 
predetermined positions preparatory to entrusting the camera to a novice 
or unskilled photographer does not contribute to the bulk, cost and/or 
weight of the camera. 
Another object of the invention is to provide a motion picture camera 
wherein the ease of selection of focal length and/or focusing at any 
selected distance from the subject is not affected by the provision of 
means for moving the adjusting elements for focal length and focusing to 
predetermined positions preparatory to entrusting the camera to an 
unskilled photographer. 
A further object of the invention is to provide a motion picture camera 
wherein the focal length can be selected so as to be suited for the making 
of acceptable exposures by a person who is not famililar wiith the purpose 
and functioning of a zoom lens and/or with the purpose of and mode of 
manipulating the focusing means. 
An additional object of the invention is to provide a photographic 
apparatus wherein at least two adjusting elements, especially adjusting 
elements of the type normally mounted on the barrel of a zoom lens, can be 
simultaneously shifted to one or more predetermined positions in which the 
apparatus can be entrusted to persons who are totally unfamiliar with the 
art of photography except for the elementary knowledge that it is 
necessary to see a selected subject in the view finder and that an 
exposure can be made by depressing or otherwise actuating the camera 
release. 
The invention is embodied in a photographic apparatus, particularly in a 
motion picture camera (preferably for use with 8-millimeter film), which 
comprises a variable-focal-length lens (i.e., a so-called zoom lens), a 
rotary collar or analogous adjusting means movable between a plurality of 
positions each corresponding to a different focal length of the lens 
whereby such positions include at least one neutral position corresponding 
to a predetermined focal length (preferably a focal length which is 
satisfactory for the making of exposures in daylight or artificial light), 
a wheel, a slide or analogous actuating means which is movable (preferably 
by hand) between operative and inoperative positions, and one or more 
levers, disks, cables or other suitable motion transmitting means for 
moving or effecting the movement of adjusting means to neutral position in 
response to movement of actuating means between operative and inoperative 
positions, irrespective of the position of adjusting means prior to such 
movement of the actuating means (of course, the adjusting means simply 
remains in neutral position if it has assumed the neutral position prior 
to movement of actuating means between operative and inoperative 
positions). 
In accordance with a presently preferred embodiment of the invention, the 
photographic apparatus further comprises at least one additional adjusting 
means (e.g., a focusing collar on the barrel of the zoom lens) which is 
also movable between a plurality of positions including at least one 
neutral position, and the motion transmitting means is preferably 
constructed and assembled in such a way that the additional adjusting 
means is moved to neutral position simultaneously with the first mentioned 
adjusting means whenever the actuating means is moved between operative 
and inoperative positions. 
The actuating means can be a rotary wheel, a rotary disk, a reciprocable 
slide, a reciprocable pusher or a pivotable lever which is movable between 
operative and inoperative positions at right angles to the optical axis of 
the zoom lens, a device which is movable in parallelism with the optical 
axis, or a device which must perform a more complex movement during 
shifting between operative and inoperative positions. 
The neutral position of the one and/or the other adjusting means may be an 
end position or an intermediate position of the respective adjusting 
means. 
The actuating means may further serve to automatically close a master 
switch in a motion picture camera wherein the film transporting mechanism 
and/or the zoom lens receives motion from an electric motor so that the 
camera is ready for the making of exposures as soon as the adjusting means 
assumes or assume the neutral position(s).

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to FIGS. 1 and 2, there is shown a portion of a motion picture 
camera which comprises a zoom lens 1 including a barrel 1a for optical 
elements 1b, a first adjusting element 2 which is a focusing collar 
rotatably mounted on the barrel 1a of the lens 1 and having a motion 
receiving projection or pin 2a, and a second adjusting element 3 which is 
a zooming collar rotatably mounted on the barrel of the lens 1 and having 
a motion receiving projection or pin 3a. The collars 2 and 3 are rotatable 
between two end positions (in which their projections 2a, 3a respectively 
assume the positions shown at 2a, 3a and the positions 2a', 3a') and 
through a plurality of intermediate positions including those which are 
indicated at 2a", 3a". For example, the positions 2a, 3a may correspond to 
those of proper focusing at a maximum distance from the subject and of 
maximum focal length, the positions 2a' and 3a' may correspond to those of 
proper focusing at a minimum distance from the subject and of minimum 
focal length, and the positions 2a", 3a" may represent proper focusing at 
a median distance (e.g., 5 meters) from the subject and a medium focal 
length. The projections 2a, 3a should assume the positions 2a" and 3a" 
(hereinafter called neutral positions) when the camera is to be 
manipulated by a novice or by an unskilled amateur photographer, i.e., 
when the person manipulating the camera should be able to make exposures 
without any adjustment of the collars 2 and 3. The neutral positions 2a", 
3a" can be readily selected in such a way that a person using the camera 
is capable of making satisfactory exposures in daylight whereby the depth 
of field is acceptable irrespective of the distance of lens 1 from the 
subject (such distance may include closeup or infinity) as well as of 
making acceptable shots in artificial light. 
In accordance with the invention, the camera of FIGS. 1 and 2 comprises 
means for rapidly moving the collars 2 and 3 to such positions in which 
their projections 2a, 3a respectively assume the neutral positions 2a" and 
3a". To this end, the housing or body 4 of the camera supports a 
reciprocable actuating member or slide 5 which is biased by a helical 
spring 6 to normally assume the first or inoperative position of FIG. 1 
and which is movable by hand (see the arrow 9) against the opposition of 
spring 6 to thereby pivot two motion transmitting levers 7 and 13. The 
lever 7 is pivotably mounted on a fixed shaft 8 and its shorter arm has an 
elongated slot 7a for a pin 5b of the slide 5. When the slide 5 is pushed 
or pulled in the direction indicated by arrow 9, the pin 5b pivots the 
lever 7 clockwise, as viewed in FIG. 1, and causes an outwardly extending 
entraining lug 7b at the free end of the longer arm of the lever 7 to move 
toward the position 7b". The projections 2a, 3a of the collars 2 and 3 are 
located in the path of movement of the lug 7b (if the angular positions of 
the collars 2, 3 are such that their projections 2a, 3a are located 
between the positions shown at 2a, 3a and the positions 2a", 3a") whereby 
the lug 7b automatically entrains the projections toward the positions 
2a", 3a". The shaft 8 carries a gear 10 which shares the angular movements 
of the lever 7 under or against the bias of the spring 6 and meshes with a 
smaller second gear 12 on a fixed shaft 11. The gear 12 pivots the lever 
13 which has an entraining lug 13a adapted to move the projections 2a, 3a 
from the positions 2a', 3a' to the positions 2a", 3a" if the projections 
2a, 3a happen to be located between the positions 2a', 3a' and 2a", 3a" 
when the user of the camera moves the slide 5 in the direction indicated 
by arrow 9. 
The projections 2a and 3a are assumed to be in the positions shown at 2a, 
3a when the user of the camera wishes to rotate the collars 2, 3 to their 
neutral positions. The user simply moves (pushes or pulls) the slide 5 in 
the direction of arrow 9 whereby the spring 6 stores energy and the lever 
7 is pivoted clockwise, as viewed in FIG. 1, to move to the position 7". 
At the same time, the lever 7 causes the gears 10 and 12 to pivot the 
lever 13 anticlockwise, as viewed in FIG. 1, whereby the lever 13 moves to 
the position 13". During such movement, the lug 13a does not engage the 
projections 2a, 3a; however, the lug 7b entrains these projections from 
the positions shown at 2a, 3a to the neutral positions 2a", 3a". If the 
projections 2a, 3a assume the positions 2a", 3a" prior to movement of the 
slide 5 from inoperative position, the angular positions of the collars 2 
and 3 remain unchanged. If the projections 2a, 3a assume the positions 
2a', 3a' (or any positions between those shown at 2a', 3a' and 2a", 3a") 
prior to movement of the slide 5, the collars 2, 3 are rotated by the lug 
13a when the slide 5 is moved against the opposition of the spring 6. It 
will be seen that the levers 7 and 13 effect a movement of projections 2a, 
3a to the neutral positions 2a", 3a" whenever the slide 5 is moved from 
the inoperative position of FIG. 1 to the second or operative position. 
The extent of such movement of the slide 5 is determined by the length of 
a slot 4a in the housing or body 4 of the motion picture camera. The major 
part of the slide 5 is concealed in the interior of the body 4, and this 
slide has a preferably serrated or knurled arm or extension 5A which 
extends outwardly through the slot 4a. 
When the spring 6 is free to retract the slide 5 to the inoperative 
position of FIG. 1, the levers 7 and 13 reassume their solid-line 
positions; however, the collars 2 and 3 remain in those positions which 
correspond to neutral positions of their projections 2a and 3a. Friction 
between the barrel 1a of the lens 1 and the collars 2, 3 is sufficient to 
normally prevent uncontrolled angular displacements of these collars 
except under the action of the entraining lug 7b and/or 13a, as well as 
when the user intentionally changes the angular positions of the collars. 
FIG. 2 shows a radially outwardly extending handle 2B which can be used by 
the operator to change the angular position of the collar 2. A similar 
handle or zoom bar (not shown) is provided on the collar 3 so that the 
operator can change the focal length of the lens 1 when the slide 5 dwells 
in the inoperative position of FIG. 1. 
The levers 7, 13 and the projections 2a, 3a can be installed in the 
interior of the barrel 1a and the projections 2a, 3a are parallel or 
substantially parallel to the optical axis 1f of the lens 1. 
FIGS. 3, 4 and 5 illustrate portions of slightly modified cameras wherein 
the motion transmitting levers 7 and 13 are replaced with substantially 
disk-shaped rotary motion transmitting members. All such parts of the 
cameras of FIGS. 3 to 5 which are identical with or clearly analogous to 
corresponding parts of the camera shown in FIGS. 1 and 2 are denoted by 
similar reference characters. 
Referring first to FIG. 3, the barrel for the optical elements 1b has been 
omitted for the sake of clarity. The motion receiving projections or pins 
2a, 3a of the collars 2, 3 extend in parallelism with the optical axis 1f 
of the zoom lens and the collar 3 has an arcuate slot 3b for the 
projection 2a. The neutral positions of the projections 2a, 3a are 
respectively shown at 2a", 3a". The actuating member or slide 5 is 
reciprocable in and counter to the direction indicated by arrow 9, i.e., 
substantially at right angles to the optical axis 1f (the same as in the 
embodiment of FIGS. 1 and 2). A helical return spring 6 biases the slide 5 
to the first or inoperative position of FIG. 3. The slide 5 has a toothed 
rack 5a which meshes with a gear 20 on a shaft 21 which is journalled in 
the housing or body (not shown) of the motion picture camera. The shaft 21 
is rigid with a smaller second gear 22 which meshes with the ring gear 23a 
of a disk-shaped rotary motion transmitting member 23. The latter 
(hereinafter called disk for short) is rotatable in the barrel of the zoom 
lens about the optical axis 1f and has an entraining projection or stud 
23b which is a functional equivalent of the lug 7a shown in FIG. 1. The 
gear 22 is further in mesh with a gear 24 on a shaft 24a which is 
journalled in the camera body and carries an additional gear 25 in mesh 
with a gear segment 26a of a second disk-shaped rotary motion transmitting 
member 26 (hereinafter called disk) which is coaxial with the disk 23. The 
disk 26 has an arcuate cutout 26d for the stud 23b of the disk 23 and the 
disk 26 carries a second entraining projection or stud 26b which is a 
functional equivalent of the lug 13a shown in FIG. 1. 
When the slide 5 is moved against the opposition of the spring 6 (see the 
arrow 9), the disks 23, 26 rotate in opposite directions and cause their 
studs 23b, 26b to entrain the projections 2a, 3a to the neutral positions 
2a", 3a" regardless of the angular positions of collars 2 and 3 prior to 
movement of the slide 5 from the inoperative position of FIG. 3 (except, 
of course, if the projection 2a and/or 3a already dwells in the neutral 
position). The diameters of the studs 23b, 26b are large enough to insure 
that each of these studs can entrain the projection 2a and/or 3a. When the 
spring 6 is free to contract, the slide 5 reassumes its inoperative 
position but the collars 2 and 3 remain in the angular positions 
corresponding to neutral positions 2a", 3a" of their projections 2a and 
3a. The handles (corresponding to the handle 2B of FIG. 2) which are used 
to change the angular positions of collars 2 and 3 in the inopertive 
position of the slide 5 are not shown in FIG. 3. If desired, the motion 
picture camera which embodies the structure of FIG. 3 can be equipped with 
a motor which serves to change the angular position of the zooming collar 
3 in the inoperative position of the slide 5. 
FIG. 4 shows that the slide 5 has a motion transmitting arm 5c which can 
directly engage and entrain the motion receiving projections 2a, 3a of the 
collars 2, 3 from the end positions 2a', 3a' to the neutral positions 2a", 
3a". The slide 5 has a toothed rack 5a in mesh with a gear 30 which is 
rotatable about the axis of a fixed shaft 30a and is in mesh with the 
toothed rack 31a of a second slide 31 which is movable in parallelism with 
the slide 5. When the slide 5 moves in the direction indicated by arrow 9 
to stress the spring 6, the slide 31 moves in the direction of arrow 9a 
and its arm 31b can entrain the projection 2a and/or 3a from the end 
position shown at 2a, 3a to the neutral position 2a", 3a". It will be 
noted that the slides 5 and 31 move in the opposite directions and that 
their arms 5c, 31b are normally adjacent to the projections 2a, 3a when 
these projections respectively assume the end positions shown at 2a, 3a 
and the end positions 2a", 3a". The spring 6 is strong enough to retract 
the slide 5 to the inoperative position of FIG. 4 and to simultaneously 
move the slide 31 to the illustrated position. It is clear, however, that 
the structure of FIG. 4 may comprise an additional spring for the slide 31 
or a single spring which biases the slide 31. 
FIG. 5 shows a modification of the camera of FIG. 4. The second slide 31 of 
FIG. 4 is replaced with a rotary disk 33 having a ring gear 33a in mesh 
with the gear 30. The latter is rotated by the slide 5 in the same way as 
described in connection with FIG. 4. The arm 33b of the disk 33 is the 
functional equivalent of the entraining arm 31b. When the slide 5 is 
caused to leave the inoperative position of FIG. 5, the arms 5c, 33b move 
toward each other whereby the arm 5c and/or the arm 33b entrains the 
motion receiving projection 2a and/or 3a and moves it to the neutral 
position (2a", 3a"). 
The directions of movement of the slides 5 shown in FIGS. 4 and 5 are 
normal to the optical axis of the optical elements 1b, the same as in FIG. 
3. 
A feature which is shared by all of the embodiments shown in FIGS. 1-2, 3, 
4 and 5 is that the motion transmitting members 7, 13 or 23, 26 or 5c, 31b 
or 5c, 33b move in opposite directions in response to movement of the 
actuating member 5 from its inoperative position. Thus, such motion 
transmitting members sweep the entire area where the motion receiving 
projections 2a, 3a can dwell at the time the user decides to move the 
collars 2, 3 to their neutral positions. The motion transmitting members 
thereupon reassume their starting or retracted positions to provide room 
for eventual movement of the collar 2 and/or 3 from the neutral position 
so that a person who wishes to change the focal length of the optical 
elements 1b (by means of the collar 3) or to focus the image of a subject 
on the foremost unexposed film frame can immediately proceed with turning 
of the collar 2 and/or 3 without renewed shifting of the actuating member 
5. 
FIGS. 6 and 7 show a modified camera which comprises means for selecting 
any one of several neutral positions for the collars 2 and 3 on the lens 
barrel for the optical elements 1b. The collars 2 and 3 respectively 
comprise motion receiving ring gears 2c, 3c which respectively mesh with 
first and second gears 42, 43. The gears 42, 43 are respectively rigid 
with coaxial shafts 44, 45, and the shaft 44 is telescoped into the shaft 
45. A friction clutch of any known design (not specifically shown) is 
interposed between the shafts 44 and 45 so that the gears 42, 43 normally 
rotate in unison but the gear 42 or 43 is rotatable relative to the gear 
43 or 42 when the respective collar reaches an end position in which the 
associated motion receiving ring gear is held against further rotation. 
The shaft 45 for the gear 43 surrounds a coaxial third shaft 46a which is 
rigid with a third gear 46. A second friction clutch (not shown) is 
interposed between the shafts 45 and 46a. The gear 46 is assumed to rotate 
clockwise, as viewed in FIG. 6, when engaged by the toothed rack 41a of a 
reciprocable and pivotable driving member 41. The latter is reciprocable 
in parallelism with the actuating member of slide 5 and is pivotable about 
the axis of a shaft 47 which is parallel to the rack 41a and whose axis is 
normal to the common axis of the shafts 44, 45, 46a and to the optical 
axis 1f of the zoom lens. When the driving member 41 is pivoted 
anticlockwise, as viewed in FIG. 6 or 7, its rack 41a is disengaged from 
the third gear 46. A helical spring 48 biases the driving member 41 
upwardly, as viewed in FIG. 6 or 7, i.e., this spring tends to move the 
member 41 lengthwise of the shaft 47 in a direction counter to that 
indicated by the arrow 9. 
The slide 5 has an arm 5d which overlies the upper end face of the driving 
member 41, and the slide 5 further comprises a suitably inclined cam 5e 
which can be engaged by the follower arm 49c of a coupling lever 49 
pivotably mounted on a shaft 50 which is parallel to the shaft 47. The 
lever 49 further comprises an arm 49a and a pin 49b, both movable into 
engagement with the driving member 41. The portions 49a and 49b of the 
coupling lever 49 can engage the driving member 41 in such a way that the 
latter maintains the teeth of its rack 41a in mesh with the teeth of the 
gear 46. The means for biasing the coupling lever 49 in such direction 
comprises a torsion spring 51 which is coiled around the shaft 50, one leg 
of which engages a fixed retainer and the other leg of which bears against 
an edge face of the lever 49. The torsion spring 51 can be replaced with 
other biasing means which pushes or pulls the coupling lever 49 in a 
direction to maintain the portions 49a, 49b in engagement with the driving 
member 41. 
When the slide 5 is moved in the direction indicated by arrow 9, the arm 5d 
moves the driving member 41 in the same direction whereby the rack 41a 
rotates the gear 46 and the gear 46 rotates the gears 42, 43 and collars 
2, 3. The extent of movement of the driving member 41 with the slide 5 is 
selected in such a way that the motion receiving gears 2c, 3c can rotate 
the collars 2, 3 from first end positions (e.g., corresponding to the end 
positions 2a', 3a' of the projections 2a, 3a shown in FIG. 1) to second 
end positions corresponding to the other end positions of the projections 
2a, 3a). In other words, when the slide 5 reaches its operative position, 
each of the collars 2, 3 invariably reaches an end position (rather than a 
neutral position as in the embodiments of FIGS. 1-2, 3, 4 and 5). Thus, 
such movement of the slide 5 invariably insures that the collars 2, 3 
rotate in unison toward one of their end positions. The clutch between the 
shafts 44, 45 allows the gear 42 to rotate relative to the gear 43 (or 
vice versa) if the collar 2 reaches the selected end position ahead of the 
collar 3 (and vice versa). The clutch between the shafts 45 and 46a allows 
the shaft 46a to rotate relative to the shafts 44, 45 if both collars 
reach the selected end positions before the slide 5 reaches its operative 
position. 
When the upper end face of the driving member 41 moves below the plane of 
the coupling lever 49, the torsion spring 51 can pivot the lever 49 
clockwise, as viewed in FIG. 7, so that the arm 49a moves above the 
driving member 41 and thus extends into the path of return movement of the 
member 41 under the action of the spring 48. When the slide 5 reaches its 
operative (lower end) position, the upper end face of the driving member 
41 is spaced apart from and is located below the arm 49a (see the distance 
c in FIG. 7). The rack 41a remains in mesh while with the gear 46 because 
the driving member 41 is still engaged by the pin 49b of the coupling 
lever 49. 
The user of the camera thereupon releases the slide 5 so that the spring 6 
is free to contract and to move the slide upwardly, as viewed in FIG. 6 or 
7. The driving member 41 can share the initial stage of such movement of 
the slide 5 because it is biased by the spring 48; however, the member 41 
is arrested by the arm 49a as soon as it covers the distance c. During 
movement counter to the direction indicated by the arrow 9, the rack 41a 
rotates the gear 46 in a counterclockwise direction whereby the gears 46, 
43, 42, 3c and 2c rotate in unison and move the collars 2, 3 to their 
netural positions (corresponding to the positions 2a", 3a" of the 
projections 2a, 3a shown in FIG. 1). The slide 5 continues to move 
upwardly under the action of the spring 6 (i.e., the slide 5 moves 
relative to the driving member 41 which is held by the arm 49a of the 
coupling lever 49) whereby the cam 5e engages the follower arm 49c and 
pivots the lever 49 anticlockwise. This disengages the portions 49a, 49b 
of the lever 49 from the driving member 41 so that the latter is free to 
pivot on the shaft 47 (anticlockwise, as viewed in FIG. 6 or 7), under the 
action of a torsion spring 53 which disengages the rack 41a from the gear 
46. The spring 48 is free to return the driving member 41 to the upper end 
position whereby the angular position of the gear 46 remains unchanged 
because this gear is not in mesh with the rack 41a. When the slide 5 
reaches its inoperative position, the cam 5e is located at a level above 
the follower arm 49c and the coupling lever 49 is free to assume the 
position shown in FIG. 6 in which the camera can be used for the making of 
exposures with a lens of average focal length and with the focusing collar 
2 in a neutral position in which the image of a subject located at an 
averge distance from the optical elements 1b (e.g., at a distance of 5 
meters) is sharply focussed on the foremost unexposed frame of 
photographic film (e.g., 8-millimeter film) in the body of the motion 
picture camera. 
The handles (not shown) enable a skilled photographer to change the angular 
positions of the collars 2, 3 when the slide 5 dwells in the inoperative 
position of FIG. 6. 
The purpose of the gear 54 on the shaft 46a is to allow for selection of 
different neutral positions for the collars 2, 3. Thus, all that is 
necessary to change from one pair of neutral positions to another pair of 
neutral positions is to move the rack 41a of the driving member 41 from 
mesh with the gear 46 into mesh with the gear 54 or vice versa. This can 
be achieved by moving the driving member 41 relative to the gears 46, 54 
or by moving the shaft 46a for the gears 46, 54 relative to the driving 
member. The number of teeth on the gear 54 is greater or less than the 
number of teeth on the gear 46 so that the angular displacement of collars 
2, 3 when the driving member moves upwardly to cover the distance c, is 
different when the rack 41a meshes with the gear 46 than when the rack 41a 
meshes with the gear 54. For example, the gear 46 may be used to move the 
collars 2, 3 to first neutral positions which are best suited for the 
making of exposures in daylight and at a first distance (e.g., 5 or 6 
meters) from the subject, and the gear 54 may be used to move the collars 
2, 3 to second neutral positions (in which the lens can be located at a 
distance of 4 meters from the subject) when the camera is to be used for 
the making of exposures in artificial light. The focal length of the lens 
is preferably less when the camera is to make exposures with flash. 1a, 
FIG. 8 shows a portion of a motion picture camera wherein the angular 
positions of collars 2 and 3 can be changed by cords, cables or analogous 
flexible motion transmitting members 61, 62. The collars 2 and 3 are 
respectively provided with motion receiving posts or studs 2E, 3E and the 
forward ends of the motion transmitting members 61, 62 (hereinafter called 
cables for short) are secured to the respective posts. The cable 61 passes 
through the nip of two guide rolls 63, 64 which are mounted in the barrel 
1a, and the cable 62 passes through the nip of two guide rolls 65, 66 
which are mounted in the barrel 1a or in the body of the motion picture 
camera. The collar 2 assumes its neutral position when the portion of the 
cable 61 between the motion receiving post 2E and the nip of the guide 
rolls 63, 64 is parallel to the optical axis 1f, and the collar 3 assumes 
the neutral position when the portion of the cable 62 between the motion 
receiving post 3E and the nip of the guide rolls 65, 66 is parallel to the 
axis 1f. The rear ends of the cables 61, 62 are respectively secured to 
the peripheries of two rotary members or pulleys 67, 68 which are coaxial 
with a rotary driver disk 69. Suitable one-way friction clutches (not 
specifically shown) are interposed between the rotary members 67, 68 and 
68, 69 so that the pulleys 67, 68 normally share the anticlockwise 
movements of the disk 69 but the latter is free to rotate clockwise with 
respect to both pulleys. The disk 69 can be rotated clockwise or 
anticlockwise by a wheel-shaped actuating member 70 through the medium of 
a rod 70a. The wheel 70 is biased clockwise, as viewed in FIG. 8, by a 
helical spring 71 which tends to maintain the wheel in the inoperative 
position. Each of the cables 61, 62 may comprise an elastic portion which 
enables the respective cable to change its length (within certain limits). 
When the user of the camera wishes to change the angular position of the 
collar 2 and/or 3, the respective collar is rotated by hand (e.g., by 
resorting to a suitable handle corresponding to the member 2B of FIG. 2) 
whereby the pulley 67 rotates relative to the pulley 68 and disk 69, the 
pulley 68 rotates relative to the pulley 67 and disk 69, or the pulleys 
67, 68 rotate (with or relative to each other) with respect to the disk 
69. If the user wishes to move the collars 2 and 3 to their neutral 
positions, the wheel 70 is rotated counterclockwise to stress the spring 
71 and entrains the disk 69 in the same direction. The disk 69 rotates the 
pulley 67 and/or 68 through the medium of the respective one-way 
clutch(es) until the collars 2, 3 reach their neutral positions. The wheel 
70 is thereupon released so that the spring 71 contracts and returns the 
members 69, 70 to their inoperative positions. The one-way clutches allow 
the disk 69 to rotate with respect to the pulleys 67, 68 so that the 
collars 2, 3 remain in their neutral positions. 
If the motion receiving posts 2E, 3E are replaced with spherical motion 
receiving elements (such as the spherical element 73 of FIG. 9 which has a 
diametrically extending slot 73a for the front end of the cable 61), and 
the spherical elements 73 are biased by springs (see the spring 72 which 
biases the element 73 toward the adjacent end face or shoulder 1e of the 
barrel 1a), the element 73 snaps between the guide rolls 63, 64 when the 
collar 2 reaches its neutral position (see FIG. 10) and the collar then 
remains in such neutral position until and unless it is subjected to 
torque of a magnitude which is needed to expel the spherical element 73 
from the space between the rolls 63, 64. The spherical element 73 is 
movable in a bore 2e which is machined into the collar 2 and is parallel 
to the optical axis 1f. This spherical element cooperates with the rolls 
53, 64 to constitute therewith a detent which yieldably holds the collar 2 
in neutral position. An advantage of such detent is that the movements of 
the collar 2 to neutral position are reproducible with a maximum degree of 
accuracy, especially if the cable 61 comprises an elastic portion. The 
spherical element (not shown) for the front end of the cable 62 is 
analogous to the element 73. 
Referring to FIG. 11, there is shown a portion of a motion picture camera 
wherein the zoom lens 101 comprises collars 102, 103 (respectively 
corresponding to aforedescribed collars 2, 3) which are rotatable about 
the optical axis 1f and can move to neutral positions in response to 
movement of an actuating member or slide 105 from the inoperative position 
of FIG. 11. In accordance with a feature of this camera, the slide 105 is 
reciprocable in and counter to the direction indicated by arrow 109, i.e., 
by moving in parallelism with the optical axis 1f. This is desirable and 
advantageous because the slide can be pushed against the opposition of a 
return spring 106 by the thumb of an operator so that the remaining 
fingers of the same hand can be used to manipulate other components of the 
motion picture camera. 
The collars 102, 103 respectively comprise motion receiving projections 
102a, 103a which correspond to the projections 2a, 3a of FIG. 1 and extend 
in parallelism with the optical axis 1f. FIG. 11 shows the collars 102, 
103 and their projections 102a, 103a in intermediate positions (but not in 
those intermediate positions which constitute the neutral positions). In 
the neutral position of the collar 2, the lens is properly focused upon a 
subject which is located at an average distance (e.g., 5 meters) from the 
camera. The focal length of optical elements in the barrel 101a of the 
zoom lens 101 is an average focal length. This insures that, if the 
exposures are made in satisfactory daylight, the depth of field is 
acceptable in the entire range of distances including infinity. Also, the 
neutral positions can be selected in such a way that the camera can make 
satisfactory exposures in artificial light. 
The slide 105 has an elongated slot 105b for a pin 107a on a rearwardly 
extending arm 107b of a plate-like support 107 which is mounted on the 
barrel 101a. The slide 105 further includes an elongated toothed rack 105a 
in mesh with a gear 120 which meshes with a toothed rack 121c forming part 
of a slide 121 which is movable at right angles to the direction indicated 
by arrow 109. The gear 120 is mounted on an arm of the support 107. The 
slide 121 has elongated slots 121a for guide pins 107c of the support 107 
and includes a second toothed rack 121b which is in mesh with a gear 122 
rotatably mounted on the support 107. The gear 122 is coaxial and rigid 
with a gear 125 and meshes with a ring gear 123a forming part of a 
disk-shaped rotary motion transmitting member 123. The gear 125 meshes 
with the ring gear 126a of a second disk-shaped rotary motion transmitting 
member 126 which is coaxial with the disk 123. The disks 123, 126 
respectively comprise entraining lugs 123b, 126b which correspond to the 
lugs 7b, 13a of the levers 7, 13 shown in FIG. 1. Thus, the lugs 123b, 
126b can move through sufficient angular distances to insure that they 
entrain the motion receiving projections 102a, 103 a and move the collars 
102, 103 to neutral positions not later than when the slide 105 reaches 
its operative (depressed) position. The gear 125 is smaller than the gear 
122 so that the disks 123, 126 rotate relative to each other when the 
slide 105 is moved forwardly (arrow 109). If desired, the camera of FIG. 
11 may comprise means for rotating the gear 125 clockwise in response to 
anticlockwise rotation of the gear 122 or vice versa; this renders the 
structure of FIG. 11 even more similar to the structure of FIG. 1. 
When the pressure upon the slide 105 is relaxed so that the spring 106 is 
free to move the slide 121 downwardly (as viewed in FIG. 11) and to 
thereby move the slide 105 counter to the direction indicated by arrow 
109, the lugs 123b, 126b move away from the projections 102a, 103a and the 
collars 102, 103 remain in their neutral positions until and unless the 
user decides to move the collar 102 and/or 103 to the one or other end 
position or to an intermediate position other than the neutral position. 
It will be noted that the support 107 carries the slides 105, 121 and the 
gears 120, 122, 125. In addition, the support 107 preferably carries the 
optical elements 128, 129, 130, 131 and 132 of the view finder, light 
meter or range finder of the motion picture camera. This is desirable and 
advantageous since, and in view of the fact that the support 107 is 
mounted on the barrel 101a, all components of the zoom lens plus the means 
for moving the collars 102, 103 to neutral positions and the view finder 
can be assembled and properly adjusted before the barrel 101a is attached 
to the camera body. As mentioned above, the movability of slide 105 in 
parallelism with the optical axis 1f is desirable and advantageous because 
the slide 105 can be oved by the thumb, i.e., by that finger which is less 
likely to be necessary for manipulation of other components or elements of 
the camera. Consequently, other fingers of the same hand can be used while 
the thumb pushes the slide 105 against the opposition of the spring 106. 
This spring actually pulls the slide 121 downwardly, as viewed in FIG. 11 
whereby the gear 120 tends to rotate the slide 105 in a direction to the 
right, i.e., counter to the direction indicated by arrow 109. 
FIG. 12 shows a zoom lens 201 having a barrel 201a and optical elements 
201b. The collars 202 and 203 respectively correspond to the collars 2 and 
3 of FIGS. 1 and 2. The barrel 201a futher carries a braking and clamping 
member 204 (hereinafter called shoe or brake shoe for short) which can be 
moved into frictional engagement with the collars 202 and 203. The shoe 
204 is pivotable about the axis of a shaft 205 and is biased by a torsion 
spring 206 in a direction to engage the collars 202 and 203. This shoe 
resembles a two-armed lever one arm of which can engage the collars and 
the other arm of which extends rearwardly and is formed with a slightly 
bent rear end portion 204a receivable in a recess or socket 207a of a 
tubular sleeve-like actuating member 207. The member 207 is movable 
forwardly (arrow 208) toward an operative position against the opposition 
of a helical spring 209. The collars 202, 203 are coaxial with the 
actuating member 207 (hereinafter called sleeve). 
FIG. 12 shows that the collars 202 and 203 are respectively provided with 
motion receiving projections 202a, 203a. These collars are movable in 
opposite directions, i.e., one of the collars must be rotated clockwise 
from an end position to thereby effect appropriate changes in focal length 
or to bring the image of a subject into focus, and the other collar must 
be rotated counterclockwise, again from an end position. The projections 
202a, 203a are respectively connected with helical motion transmitting 
springs 201, 211 which are further connected to a retainer 212 on the 
barrel 201a. The force with which the shoe 204 can engage the collars 
202, 203 in order to hold the collars against rotation exceeds the maximum 
bias of the springs 210 and 211. 
In FIG. 12, the shoe 204 engages the collars 202 and 203. Therefore, when 
the user of the camera changes the angular position of the collar 202 or 
203 against the opposition of the respective spring 210 or 211, the collar 
202 or 203 remains in the newly selected angular position because the 
braking force of the shoe 204 cannot be overcome by the spring 210, 211, 
even if both springs are stressed to a maximum extent. 
If the user thereupon decides to move the collars 202 and 203 to the 
neutral positions, the sleeve 207 is moved in the direction indicated by 
arrow 208. The inclined cam surface in the groove 207a engages the end 
portion 204a and pivots the shoe 204 against the opposition of the spring 
206 whereby the shoe releases the collars 202, 203 and the springs 210, 
211 are free to dissipate energy. When the collars 202 and 203 reach the 
aforementioned end positions, the focal length of the zoom lens 201 is set 
for an average value and the image of a subject is in sharp focus if the 
camera is held at a distance of 5 or 6 meters from the subject. When the 
sleeve 207 is released so that it can be moved by spring 209 back to the 
inoperative position of FIG. 12, the spring 206 returns the shoe 204 into 
frictional engagement with the collars 202 and 203 which then remain in 
the respective neutral positions until and unless the operator decides to 
move the collars 202 and/or 203 to a different angular position, i.e., to 
stress the spring 210 and/or 211. 
The zoom lens of FIG. 13 differs from the zoom lens 201 of FIG. 12 in that 
each of the collars 202, 203 is biased by two motion transmitting springs 
acting in opposite directions. Thus, the collar 202 is biased by two 
helical springs 210a, 210b which are attached to the motion receiving 
projection 202a. The springs 210a, 210b are further respectively attached 
to retainers or posts 212b, 212a. Analogously, the springs 211a, 211b for 
the collar 203 are attached to the projection 203a, and the outer ends of 
these springs are respectively attached to the posts 212b, 212a. The posts 
212a, 212b are mounted on the barrel 201a. The sleeve 207 has a forked 
extension or detent 214 with a slot 214a the outer end of which is flanked 
by two inclined guide faces 214b. 
The inoperative position of the sleeve 207 is shown by phantom lines and 
the operative position is shown by solid lines. When the sleeve 207 is 
moved toward the operative position, the shoe 204 is disengaged from the 
collars 202, 203 and the springs 210a, 210b and 211a, 211b are free to 
move the respective collars to their neutral positions. The forked 
extension 214 shares the forward movement of the sleeve 207 and its 
inclined faces 214b guide the projections 202a, 203a into the slot 214a to 
thus insure that the neutral positions of the collars 202, 203 are the 
same in response to each forward movement of the sleeve. In other words, 
the extension 214 insures that the collars 202, 203 invariably assume 
their neutral positions as soon as the projections 202a, 203a enter the 
slot 214a, even if the springs 210a to 211b exhibit a tendency to move the 
collars back and forth to both sides of the neutral positions. 
When the spring 209 is free to contract, the sleeve 207 returns to the 
inoperative position and the shoe 204 engages the collars 202, 203 to hold 
them in neutral positions. Since the braking action of the shoe 204 is 
stronger than the bias of the springs 210a to 211b, the operator can move 
the collar 202 and/or 203 from neutral position and the collar 202 and/or 
203 then remains in the newly selected position. 
The sleeve 207 of FIGS. 12 and 13 may be provided with a suitably 
configurated recess 207b for insertion of a thumb which is used to move 
the sleeve to its operative position. 
An advantage of the zoom lenses of FIGS. 12 and 13 is that the motion 
transmitting means (springs 210, 211 or 210a to 211b) need not be 
connected to the actuating member 207. This contributes to simplicity of 
such motion transmitting means. All the actuating member 207 has to do is 
to disengage the shoe 204 from the collars 202, 203 whereby the springs 
automatically move both collars to neutral positions (unless the one or 
the other collar has been moved to neutral position prior to movement of 
actuating member 207 to the operative position). 
Another advantage of the zoom lenses of FIGS. 12 and 13 is that the shoe 
204 normally bears against the two collars to that the collars remain in 
selected angular positions with a higher degree of reliability than if 
such selected positions were maintained solely as a result of frictional 
engagement between the collars and the barrel. This is achieved by 
increasing the force which is necessary to change the angular positions of 
the collars because such force must overcome the friction between the shoe 
204 and the collars as well as the resistance of the springs 210, 211 or 
210a to 211b. 
Referring finally to FIGS. 14 and 15, there is shown a portion of a further 
motion picture camera which comprises a battery-operated motor (not shown) 
for film transport and/or for the zoom lens (not shown). FIG. 14 merely 
shows an actuating member 301 which is assumed to correspond to the 
actuating member 105 of FIG. 11 and is biased to inoperative position by a 
helical spring 302. The manner in which the movement of actuating member 
301 to operative position results in movement of collars on the barrel of 
the zoom lens to neutral positions is the same as described in connection 
with FIG. 11. When the actuating member 301 dwells in the inoperative 
position of FIG. 14, the collars on the barrel can be rotated with or 
relative to each other between two spaced-apart end positions and to any 
one of a practically unlimited number of intermediate positions (including 
one or more neutral positions). The actuating member has an entraining 
shoulder 303 and is reciprocable (in and counter to the direction 
indicated by arrow 304) in parallelism with the optical axis of the zoom 
lens. It is clear, however, that the actuating member 301 can be mounted 
for movement at an angle to the optical axis, for example, tangentially of 
the barrel in a manner similar to that shown in FIGS. 1 to 10. 
The motion picture camera comprises a so-called master switch 305 which 
must be closed prior to actuation of the release trigger 309 in order to 
enable the motor to transport the film and/or to change the focal length 
of the zoom lens. The master switch 305 should normally remain open to 
avoid premature exhaustion of the battery, batteries or other source or 
sources of electrical energy for the motor or motors of the motion picture 
camera. As shown in FIG. 15, the master switch 305 comprises a slidable 
handgrip member or knob 305a whose front face is serrated and which 
extends from or is accessible in the camera body. The knob 305a is movable 
in and counter to the direction indicated by arrow 304. When the knob 305a 
is moved to the "O" position, the master switch 305 is open to prevent 
gradual exhaustion of one or more batteries, not shown. In such "O" 
position of the knob 305a, a springy contact 306 of the master switch 305 
does not engage any of the four terminals 307a, 307b, 308a, 308b of the 
master switch. These terminals are connected in the electric circuit of 
the camera. The terminals 207a, 307b and 308a, 308b are respectively in 
parallel with each other and in series with the motor switch (not shown). 
The motor switch is closed in response to actuation of the camera release 
309, i.e., in response to movement of such release counter to the 
direction indicated by arrow 304. 
The knob 305a of the master switch 305 is movable from the "O" position to 
a position "E" (by moving in the direction indicated by arrow 304) in 
which the circuit is completed because the two arms of the springy contact 
306 engage the terminals 307a, 308a. Still further, the knob 305a is 
movable (in the direction indicated by arrow 304) to a position "BK" in 
which a pointer (not shown) or the like assumes a position which is 
indicative of the charge of the batteries. To this end, the knob 305a is 
connected with an elongated trip 310 having a bent-over front portion or 
lug 310a which closes a battery check switch 311 when the knob assumes the 
position "BK". 
The knob 305a of the master switch 305 is further movable to a position "D" 
(the knob reaches such position by moving from the position "BK", "E" or 
"O" counter to the direction indicated by arrow 304) in which the arms of 
the springy contact 206 engage the terminals 307b and 308b to complete the 
corresponding part of the electrical circuit of the camera. When the knob 
305a assumes the position "D", a pawl 312 (which is biased by a leaf 
spring 311a or the like) can enter a notch 310c of the trip 310 whereby a 
projection 312a of the pawl 312 engages a complementary projection 309a of 
the release 309 and maintains the latter in depressed position so that the 
camera can make a series of exposures, even if the finger pressure upon 
the release 309 is relaxed or terminated. 
A detent 313 (e.g., a sphere) is preferably provided to yieldably hold the 
knob 305a in the position "O". To this end, the detent 313 is biased by a 
spring 313a and penetrates into a suitably configurated notch 310b of the 
trip 310 when the knob 305a reaches the "O" position. 
The knob 305a of the master switch 305 is received in an elongated slot 
314a of a motion transmitting slide 314 which is reciprocable in and 
counter to the direction indicated by arrow 304. The slide 314 has an 
extension 314b which is located in the path of movement of the shoulder 
303 on actuating member 301. The length of the slot 314a is such that the 
knob 305a can be moved by hand relative to the slide 314, i.e., that the 
user of the camera can move the knob 305a to any of the positions "O", 
"D", "E" and "BK". However, the extent to which the actuating member 301 
can move the slide 314 when the collars on the barrel are to be moved to 
neutral positions is always sufficient to move the knob 305a to the 
position "BK" when the actuating member 301 reaches its operative 
position. Thus, the slide 314 automatically moves the knob 305a from the 
position "D", "O" or "E" and all the way to the position "BK" whenever the 
user of the camera decides to move the collars for focusing and focal 
length adjustment to their neutral positions. This enables the user to 
check the condition of batteries whenever the actuating member 301 reaches 
its operative position. When the actuating member 301 reaches the 
operative position, the trip 310 not only closes the battery check switch 
311 but also stresses the elastic contacts of the switch 311, i.e., such 
contacts store energy and move the knob 305a to the position "E" as soon 
as the spring 302 is free to dissipate energy in order to return the 
actuating member 301 to the inoperative position of FIG. 14. Consequently, 
the master switch 305 is closed in automatic response to movement of the 
actuating member from inoperative position to operative position and back 
to inoperative position so that the user can start with the making of 
exposures by the simple expedient of depressing the release 309. Such 
exposures are made while the collars assume their neutral positions 
unless, of course, the user has decided to change the position of the one 
and/or the other collar prior to depression of the release. 
An important advantage of the camera which embodies the structure of FIGS. 
14 and 15 is that the camera is invariably ready for the making of 
exposures when the collars on the barrel of the zoom lens are caused to 
assume their neutral positions in response to movement of actuating member 
301 to operative position. This insures that an unskilled photographer who 
is not familiar with the purpose and/or art of focussing and/or zooming 
can make exposures of acceptable quality under different circumstances by 
the simple expedient of shifting the actuating member 301 against the 
opposition of the spring 302 and by thereupon permitting the spring 302 to 
return the actuating member to inoperative position. The slide 314 
constitutes but one form of motion transmitting means which can be used to 
move the knob 305a to the position "BK" in response to movement of the 
actuating member 301 against the opposition of the spring 302. Such slide 
can be replaced by one or more levers, a gear trian, a system of cables or 
any other motion transmitting means which can insure that the master 
switch 305 is closed not later than when the actuating member reassumes 
its inoperative position. 
If the camera does not have a battery check switch, the elastic contacts of 
the switch 311 shown in FIG. 15 are replaced by a spring (not shown) which 
is stressed when the actuating member 301 reaches its operative position 
and which thereupon dissipates energy to move the knob 305a to the 
position "E". Alternatively, and especially in the absence of a battery 
checking device, the movement of actuating member 301 can result in 
movement of the knob 305a to the position "E" as soon as the member 301 
reaches its operative position. 
The switch 305 may constitute (or be replaced by) a selector switch, e.g., 
a switch which selects the motor speed. 
Without further analysis, the foregoing will so fully reveal the gist of 
the present invention that others can, by applying current knowledge, 
readily adapt it for various applications without omitting features that, 
from the standpoint of prior art, fairly constitute essential 
characteristics of the generic and specific aspects of our contribution to 
the art and, therefore, such adaptations should and are intended to be 
comprehended within the meaning and range of equivalence of the appended 
claims.