Improvements in Photographic Apparatus.
Year: 1891

page_text: Date of Application, 16th July, 1891-Accepted, 31st Oct., 1891
Improvements in Photographic Apparatus.
I, NEWNHAM BROWNE, of 73, Cheapside in the City of London, Fellow of the
Institute of Patent Agents, do hereby declare the nature of this invention which has
been communicated to me by Franz Richard Hüttig, of the firm of R. Hüttig & Son,
of Dresden, in the Empire of Germany, Manufacturers of Photographic Apparatus
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
The present improvements relate to photographic apparatus which as represented
in the annexed drawing, consist of a part A, provided with a lens, a part B provided
with the focussing slide, a bellows C, connecting the two, the said three parts
forming the camera proper and further comprising two plates D and E sliding one
on the other forming the base board and resting upon a head or support F.
Fig. 1 of the accompanying drawings represents in side elevation a photographic
apparatus of this description.
Fig. 2 represents a transverse section on the line I, I.
The lens part A together with the portion D of the base board move with
reference to the part E of the baseboard, the camera part B with the focussing
screen being similarly adjustable together with the the sliding part E.
For the purpose of adjusting the focussing glass in B upon the base plate E the
glass has usually been adjusted by sliding it backwards and forwards by hand.
The accurate adjustment by these means was a tedious operation.
By means of the following arrangement the operation is simplified and is enabled
to be performed with great precision.
The sliding plate E of the baseboard is provided on both sides with a rack bar a
gearing with pinions 6 which are fixed upon one spindle c working in bearings on
the body B of the camera. This spindle is provided at each end with a milled
head c¹ by means of which it can be rotated by hand. According to the direction
in which the spindle c is thus rotated the pinions 6 act upon the racks and move the
part B forwards or backwards relatively to the part E thus greatly facilitating the
accurate adjustment of the focussing glass as the smallest movements of the part B
upon the part E is enabled to be produced with great ease and precision.
In order to obtain a good picture it is necessary that all those parts of the
photographic apparatus that are moveable relatively to one another admit of being
so fixed when adjusted before the exposure as to exclude the possibility of the
slightest shaking or disturbance of the relative positions of the several parts of the
appara us.
An arrangement obtaining this result and applicable to all the parts of a photo-..
graphic apparatus which required to be fixed in position forms a second improvement
in photographic apparatus.
This arrangement is illustrated in Figs. 3 and 4 as being applied to the fixing of
the part B upon the part E for example being constructed as follows:
On both sides of the part B metal plates d are provided the lower edges of
which are bent inwards so as to embrace the under side of the part E. A spindle e
works in bearings in these plates being provided at both ends with a handle g.
This spindle is provided with a cam or excentric e' inside each plate d. A metal
wearing-plate fis provided under each excentric e' to protect the wood work of the
part B from the action of the said excentric.
During the operation of shifting or adjusting the part B upon the part E the
excentric & occupy the position indicated by the dotted lines in Fig. 4 in which

page_text: position they are incapable of exerting pressure upon the part B. In order to fix
the part B upon the part E the spindle e is rotated in such a manner that the
longest radius of the cam or excentric is directed downwards thereby forcing down
the part B and jamming it against the part E.
Tightening devices of this description may be applied with suitable modifications
in older forms of photographic apparatus for clamping the lens-carrier or front A
upon the baseboard D and for clamping the baseboard D E upon the head or
Support F.
The third improvement forming the object of the present invention relates to
means for locking the dark slide when in the part B of the photographic apparatus.
In the accompanying drawing a camera is shown in which the focussing screen
is hinged to the camera-body, and the screen as well as the dark-slide fit into a
groove on the body B. When the slide is to be put into place for the purpose of
working an exposure, the screen is swung round on the hinges. On each of the
upright portions of the body B, which form the guide for the dark slide, one of
said locking devices, shown in Fig. 5, is provided. Their construction is as
follows:-
On each side of the part B there is a spring plate h. Through these plates is
passed a rod or spindle k working in bearings in the part B and provided at each
end with a handle being also provided inside the part B with screws or worms l.
The latter are inclined in opposite directions and are capable of acting upon tappets
or pins m attached to the spring plates h.
Each plate h also carries a bolt n which catches in the front part of the slide
when the latter is inserted the front end of the bolt being bevelled in the direction
of the movement of the slide.
.
When the plates h are arranged at the upper part of the part B as représented
in the drawing the bolts n hold the slide B in position the spindle k and worm /
being in the position in which they do not act upon the pins m. By rotating the
spindle by means of the handles in the proper direction for bringing the worms ?
into action the latter are caused to act upon the pins m and force the upper
extremities of the spring plates outwards into the position indicated by dotted lines
in the drawing. In this position the bolts n are disengaged from the slide B¹ and
the latter can be opened.
After releasing the handles the worms and spindle k are returned to their
original position automatically by the pressure of the spring plates acting on the
pins m.
The ends of the bolts projecting inwardly beyond the surface of the sides of the
part B being inclined or bevelled enable the slide to be pushed back into the rabbet
in the part B the spring plates yielding until the ends of the bolts spring back into
the holes or recesses provided for 'their reception in the slide and hold the latter in
position. The said locking arrangement will in like manner keep the focussing
screen in position when required.
The arrangements hereinbefore described can be employed in photographic
apparatus either individually or collectively.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed as communicated to me by
my foreign correspondent I'declare that what I claim is:
The following improvements in photographic apparatus employed either separately
or in combination, namely
1. The arrangement for adjusting the focussing part B consisting of the racks a
attached to the sliding base and the pinions 6 on the spindle c working in bearings
in the part B.
2. The arrangement for fixing the lens carrier A on the base-board D or the
body B on the base E or the parts D E on the head or support F and consisting of
a revolvable spindle e working in the plates d and provided with cams or

page_text: excentrics which by a corresponding rotary motion of the spindle e join the
moveable part against the fixed or stationary part.
3 The arrangement for fixing the slide B₁ in the part B characterised by the
spring plates h carrying pins m acted on by worms or helices carried by a common
spindle in combination with the bolts n bevelled towards the front and carried
by the plates so as to engage with the slide B'.
Dated the 16th day of July 1891.
NEWNHAM BROWNE.