Year: 1887

page_text: Date of Application, 15th Mar., 1887
Complete Left, 15th Dec., 1887
Complete Accepted, 20th Jan., 1888
I, JOHN RUDOLPH GOTZ, Optician, of 19 Buckingham Street, in the City of
Westminster do hereby declare the nature of this invention to be as follows:-
My invention relates to mechanism for rapidly opening and closing an aperture,
and is specially designed for photographic cameras.
In my improved shutter the moveable cover of the aperture is formed by a rolling
or sliding disc, and its motion is produced by a spiral spring enclosed in a spring
barrel. The said barrel is made in one piece with a crank disc, the pin of which is
joined to the axle of the shutter disc by a short connecting rod. The circumference
of the crank disc has a tooth or detent piece, (or the crank pin itself may be used for
this purpose), which is held by the inner arm of a locking lever, operated by a
pneumatic releasing mechanism comprising an air cylinder with piston, piston rod
and balanced lifting lever.
The spring is wound by a knob on the pin of the crank disc which acts on the
connecting rod, and the tension of the spring produced by turning the said knob,
two, three, or more times determines the speed of the shutter. The number of turns
or charges of the spring is preferably indicated by a star wheel or rack or sector
gearing with a single tooth formed on, or attached to the circumference of the crank
disc. For further regulating the speed of revolution of the crank disc, a brake may
be applied, consisting of a spring attached at one end to the revolving crank
disc and pressing with the other end on the axle on the spring or on any other fixed
part.
To consume the accumulated energy of the fly wheel or crank disc, and diminish
the shock when one discharge has taken place, a brake spring is secured to the frame
of the shutter so as to press against the crank pin, and rest upon a pin of the locking
lever.
This brake pin may either have the shape of a bow screwed at both ends to the
frame of the shutter and pressing with its curved central part against the crank pin,
or it may have the shape of an open loop fixed to the frame at one end, and pressing
with the other or free end upon the crank pin. The pressure of this brake spring

page_text: may be regulated by means of a wedge or a screw: preferably a wedge acting on the
under side of the spring and terminating in a screw spindle which passes through the
side of the shutter frame and can be set by a screw nut.
A suitable break for the crank dise may also be formed by a small snail or spiral
shaped disc, pivoted on the axis of the snail, and having its circumference in contact
with that of the crank disc and placed so that the radial face or end of the snail acts
as an abutment to a tooth of the crank disc, so as to stop the latter after having
made a complete revolution. When the tooth of the crank disc strikes the snail, the
latter turns on its axis and thereby presses with its circumference against the circum-
ference of the crank disc.
The snail may be pivoted on the extremity of the locking lever, and replace the
hook of the latter, so that the single tooth of the crank disc comes in contact with the
radial face of the snail, instead of striking the locking lever directly. The snail may
be serrated at its circumference and may be replaced in its original position by means
of a spiral spring mounted on the axle of the snail.
Instead of making the circumference of the crank disc circular with a projecting
tooth or cam, the circumference may form a spiral, the ends of which are joined by a
short radial line in contact with the extremity of the locking lever; or the disc may
be truly circular, and the crank pin used as the detent or locking tooth.
FAIRFAX & WETTER,
433, Strand, London,
Agents for the Applicant.

page_text: Improvements in Instantaneous Shutters.
I, JOHN RUDOLPH GOTZ, Optician, of 19, Buckingham Street, in the city of
Westminster, do hereby declare the nature of my invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement :-
My invention relates to mechanism for rapidly opening and closing an aperture,
and is specially designed for photographic cameras.
In the following description reference will be made to the accompanying drawings,
of which Fig. 1 is a face view and Fig. 2 a longitudinal section of a shutter embodying
my invention.
The improved apparatus chiefly comprises a frame A, a rolling disc (or shutter
proper) B; a spring-barrel and crank disc C jointed to the axle of the disc B by a
connecting rod D, a locking lever E and spring F (constituting the locking apparatus)
an ordinary air cylinder G containing a movable piston, a specially constructed
balance lever H pivoted to the top of the piston red, a flexible air tube I leading to
an india-rubber ball not shown in the drawing, these parts G, H, I constituting a
pneumatic releasing mechanism.
The spring barrel C contains a spiral spring J attached at the inner end to a central
pin or stud K secured to the frame A, and at the outer end to the inside of the said
barrel. The barrel C is open in front and provided with a circular lid c. It is made
in one piece with the disc or circular frame c¹ carrying the crank pin d and a balance
weight. The circumference of the crank-disc has a tooth c³ which is held by
the inner extremity of the locking lever E, as shown by Fig. 1. The arrangement
may, however be so modified, that the crank-pin itself serves as a stop or detent for
the lever E.
As illustrated in detail by Fig. 3, the angular lifting lever H is pivoted at h to the
end of the piston rod g and has two parallel branches or plates connected by a pin h³,
as well as by a balance weight. A guide-pin g fixed to the top of the air-
cylinder G, between the two branches of the lifting lever H, prevents the latter from
turning on its fulcrum towards the side of the frame A.
For winding the spring J, the crank dise C is turned by means of the knob d¹
fixed to the crank-pin. According as the said knob is turned round one, two, three
or more times, the tension of the spiral spring J, which determines the speed of the
shutter, will be increased more or less. The number of turns may be indicated by a
star-wheel or tooth-wheel L, adapted to turn on a stud fixed to the frame A. This
wheel has a recess for every turn of the crank-pin, and the recesses are distributed
equally over the circumference of the wheel L, but so that the tooth between the first
and last recess is much wider than the others. At every turn of the crank disc, the
pin d gets into a recess of the wheel L and turns the latter ono division, until at last

page_text: the crank pin comes in contact with the wide tooth mentioned above and its further
motion is thereby prevented.
A brake spring M acting on the circumference of the wheel L prevents the
accidental turning of the same.
For further regulating the speed of the shutter, a brake spring N may be fixed at
one end to the crank disc C by means of a screw n so as to press with its other end
on the central pin K. The pressure of this spring may be varied by tightening more
or less the screw n.
The brake-spring F mentioned above is secured at one end to the raised part a of
the shutter frame A and has a U-shaped bend near to the middle of its length, so as
to press against the crank-pin d, while the opposite end rests upon a pin e fixed to the
lever E.
As the crank pin slides along the concave upper surface of the spring F, the latter
will retard the motion of the crank disc shortly before the end of every revolution,
thereby diminishing the shock of the crank pin against the extremity of the locking
lover.
When the lever E is in its locking position, the inner end will form an abutment
for the tooth or detent c³ of the crank disc C, as shown in Fig. 1, while its outer end
rests on the pin 4 of the lifting lever. As soon as the india-rubber ball at the end
of the pipe I is compressed, the piston in the cylinder G will rise and lift the piston
rod, together with the fulcrum hand the lever H. The pin h will therefore lift the
outer end of the lever E and thereby release the detent c³ from the inner end of the
locking lever. Thereupon the crank disc C, will be turned in the direction of
the arrow by the previously charged spiral spring J, until the crank pin d has
made a complete revolution round the pin K and again arrived in its lowest
position.
The pin ', in lifting the lever E, slides along its lower edge until it reaches the
pointed extremity of the lever E and slides off, after which the lever E will drop
again into its locking position. As soon as the pressure on the air bali ceases, the
piston descends, falling by itself into position for the next action.
The dotted lines in Fig. 1 show the position of the slide B, crank disc C, and
tooth when the disc has made half a revolution and the shutter is completely open.
The slide B is guided in a groove formed between the elevated part a of the frame A
and the cover K.
In order to stop the shutter, when it is completely open, the crank disc may be
provided with a lever P pivoted on a stud o, as shown in Fig. 1, and provided at its
free end with a pin and knob p.
When out of use, the pin prests in a recess of the circumference of the disc C, as
shown, and is held in this position by the pressure of a spring Q against the side or
edge of the time lever P.
If it is desired to stop the disc C after having made half a revolution, the lever P
is turned on its fulcrum o, until it has described nearly half a circle, and the pin rests
on the circumference of the disc C diametrically opposite to the crank pin d.
If now
the shutter is charged by turning the disc several times (as may be required) in
the direction opposite to the arrow, and if the locking lever E is then released, the
dise C will turn in the direction of the arrow under the influence of the spiral spring,
but only until the pin p has come in contact with the extremity of the lever E and is
thereby stopped, after having made half a revolution. In order to complete the
revolution and move the slide Bagain into its closing position, the locking lever E must
again be released by a fresh pressure on the air ball, whereupon the disc C will turn
until the tooth c³ is again in contact with the extremity of the lever E.
Having now particularly described and ascertained the nature of my invention, and
in what manner the same is to be performed, I declare that what I claim is :-
1. In instantaneous shutters containing a spiral spring and a reciprocating slide
adapted to be set in motion by the said spring, the combination of a supporting frame
and guide A, with a spiral spring J, a spring barrel and balanced crank disc C, a

page_text: circular rolling slide B, a connecting rod D connecting the crank disc directly with
the axle of the said slide, a locking apparatus, and a pneumatic releasing apparatus
adapted to act on the locking apparatus.
2. In an instantaneous spiral spring shutter substantially as described, a bow
spring F secured at its ends and bent near the middle of its length, and having a
concave surface adapted to act as a brake on the circumference of the crank disc,
substantially as described.
3. In an instantaneous spiral-spring shutter, an automatic spring-brake, adapted
to produce frictional contact and thereby to retard the motion of the crank-disc
or spring barrel shortly before reaching its position of rest, substantially as
described.
4. In an instantaneous spiral spring shutter, an auxiliary brake N adapted to act
on the axle of the spring barrel.
5. In an instantaneous spiral spring shutter, a star wheel or tooth wheel Lor
equivalent device adapted to indicate and limit the number of turns of the spiral
spring, substantially as described.
6. In an instantaneous spiral spring shutter having a spring barrel, crank disc and
locking apparatus adapted to operate substantially as described, a time lever P and
accessories revolving with the crank disc and adapted to stop the same, after having
made half a revolution, substantially as described.
7. In an instantaneous spiral spring shutter, the pneumatic locking and releasing
apparatus comprising locking lever E, spring F, lifting lever H, air cylinder &
with piston, piston rod, and guide post, and air tube I with elastic ball, substantially
as described.
1000