Improvements in Spraying Devices for Distributing Pigments and the like.
Year: 1897

page_text: Date of Application, 11th Mar., 1897-Accepted, 22nd May, 1897
COMPLETE SPECIFICATION.
Improvements in Spraying Devices for Distributing Pigments and
the like.
I, OLAUS CHRISTIAN WOLD, of 797 North Spaulding Avenue, in the City of
Chicago, County of Cook, State of Illinois, United States of America, Machinist,
do hereby declare the nature of this 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 artists' brushes, of the type generally known as air
brush, in which the pigment is distributed by means of air under pressure.
My invention has for its object the simplification and improvement of the
construction of brushes of this type.
In my improved form of air brush, the parts are readily assembled and
dissembled, their disposition and construction being such that any of said parts
may be readily interchanged or removed for repair without interfering with the
disposition of the remaining parts. By my improved construction a more delicate
and easy manipulation of the lever mechanism is secured.
In air brushes as heretofore constructed, the longitudinal movable needle which
controls the flow of the pigment has frictional engagement in its bearings through
a considerable portion of its length, which, in course of time causes the needle
to be worn, whereby its uniform direction of thrust is destro, 4, which results
in the delicate point of the needle coming in contact with the seat of the conical
passage in which the tapered end of the needle is adapted to fit, and through
which the flow of the pigment is controlled. If the needle be enlarged con-
siderably in cross section, this wear may be considerably reduced.
By means of my present invention, I am enabled to form the needle of as small
cross section as is desirable, since I relieve it of all frictional engagement.
I will explain my invention more particularly by reference to the accompanying
drawing, in which
Figure 1 is a side elevation partially in section of a brush embodying my
invention.
Figure 2 is a plan view thereof.
Figure 3 is a sectional view of a nozzle of the brush.
Figure 4 is a detail view showing the needle and a portion of the mechanism
immediately associated therewith.
Figure 5 is a detail view of the operating lever.
Figure 6 is a detail view of a valve pin entering into the construction of my
improved device.
Figure 7 is a plan view of a recessed nut associated with the valve pin.
Like letters refer to like parts throughout the different figures.
The particular construction illustrated in Figure 3 forms no part of my present
nvention, but in order that the application of my invention may be readily
anderstood, I have thought it well to illustrate and describe this portion of the
nechanism.
The needle a is surrounded by a sleeve b whose cross section is of square exterior
ontour at the portion 61 thereof. The portion of the sleeve is threaded. A cap
crew a¹ is secured upon the portion 6ª, a set screw a' being passed through the cap

page_text: screw into engagement with the needle, whereby the sleeve and needle are
relatively fixed. The relative longitudinal position of the sleeve and needle is
adjusted by the set screw a³.
The shell c is provided with two plates or partitions d d slightly separated, and
also with an end plate e. The plates d d' act as bearings for the forward portion
of the sleeve b. A bearing sleeve fis passed through the end plate e and is secured
thereto by threaded engagement. A cap f¹ is screwed upon a threaded extension
of the bearing sleeve, said cap being provided with a central opening through
which the contiguous portion of the sleeve b may be reciprocated.
A helical spring g is interposed between the adjustable cap and the enlarged
portion of the sleeve b. This spring tends to thrust the needle towards the
nozzle of the brush. The tension of the spring may be adjustel by the cap f
I preferably provide an annular shoulder which bears against the rear face of
the end plate when the sleeve fis screwed into position.
I provide a back lever which engages the enlarged portion 6* of the sleeve b,
and which is adapted to be turned about its lower edge by the lever i. The lever i
is linked at to the knurled thumb plate which is provided with an eye which
receives a guide mounted upon the end plate e. The guide serves to confine
the thumb plate to the path practically parallel with the axis of the needle.
When the thumb plate is thrust rearwardly the sleeve 6 and the needle is moved
backward by the back lever, the spring 9 being counteracted in this movement.
The forward motion of the sleeve b and needle is limited by the square portion ¿¹
engaging with partition .
The tuli motion of the lever plate is not imparted to the needle, however, sinco
the needle is nearer the fulcrum of the back lever, and for the further reason that
the upper end of the back lever is free to slide upwardly upon the lever i, a slight
lost motion being thus produced. It is desirable to have the travel of the thumb
plate considerably in excess of the travel of the needle actuated thereby, since a
very delicate adjustment of the needle may be had. By my construction, the
sleeve relieves the needle of all wear. As will be observed, a considerable
portion of the length of this sleeve is engaged by the containing sleeve whereby
frictional wear is greatly reduced.
A stem carrying the valve is screwed into a boss k passing through and
secured to the bottom portion of the shell c. Within the stem is provided a valve
pin, shown more clearly in Figure 6, having its upper end slotted for the
reception of a pin e³, which unites the members of the forked end of the lever i,
the pine serving as an axis or fulcrum for said lever. The pin is provided with
a shoulder which may have its upper surface faced with rubber. A coil spring
encircling the pin normally presses the shoulder l' against its valve seat, the end
of the spring resting against a nut screwed into the end of the stem. The nut l
as is shown more clearly in Figure 7 is cut away at the sides to permit the access
of air.
A sec nd stem mis illustrated, which has a cup shaped cavity at its upper
portion, in which is contained a cup like portion m² mounted upon a second valve
pin m² similar to valve pin l, this valve pin being also provided with a shoulder m³
which may have its upper surface faced with rubber. When the stems and m
are coupled, the cup like portion m' is depressed against the tension of spring m
so that air under pressure may be conducted from the supply hose m³ through a
recessed nut me similar to nut 4. When the stems and m are disunited, the
shoulder m³ is seated, whereby waste of compressed air through the hose m® is
prevented when the air brush is not being used.
Referring to Figure 3, the shell e carries in its front end, an internal thread into
which the end n¹ of the head n is adapted to be screwed. This head carries an
elongated portion or tube n², in the end of which is screwed the tip o formed
preferably of platinum. This tip is provided with a conical bore, into which the
conical end of the needle is adapted to fit.
By moving the needle a forward, the surface of the needle may be brought into

page_text: contact with the walls of the bore, thus sealing the outlet. In practice, however,
it is preferable to so adjust the needle in relation to the sleeve b that the needle
will never quite seal the outlet. By moving the needle back to a greater or less
extent, the passage between the needle and the bore may be adjusted as desired.
An annular passage is provided between tip o and the interior wall of the cap p
for the exit of air.
An annular groove n³ is provided in the end n² of the head n, the groove
communicating by a duct n' with the air chamber c. Ducts n³ extend through the
head thus connecting the groove n³ with the reservoir p' provided between the
head and the cap p. Air thus passes from the chamber through duct n',
groove n³ and ducts into the reservoir pl, from whence it passes through an annular
outlet between the stem and the end of the cap, the air thus passing in a column
surrounding the outlet for the paint, thus drawing the paint from the paint receptacle.
The paint is placed within the shell and rests upon the partition which separates
the paint receptacle from the air chamber. The air enters the chamber c¹ through
the duct r, communicating with the bore of the stem k. The air is admitted by
a downward pressure upon the lever i, the air finding passage to chamber c
through the duct r.
In the construction hitherto employed, a portion of the paint passed through the
forward bearing of the needle and came in contact with and injured the operating
mechanism of the brush. By providing the double partition d d¹ with a slight
interspace between the same, the paint that is carried backward is caught between
the partitions and is prevented from entering that portion of the shell c which
contains the lever mechanism.
It frequently becomes desirable to remove the stem k, which, with the construction
heretofore employed, was not possible without first removing the needle, but by
extending the valve pin above the stem and slotting the same, 1 free the
engagement of the lever i with the stem, whereby the stem may be readily screwed
into place or removed without interfering with the said lever, while at the same
time the air is controlled with equal facility. It will be apparent also, that the
needle may be readily removed with but slight trouble and without interfering
with the condition of the lever mechanism or valve pin.
Changes may be readily made in my invention without departing therefrom, and
I do not therefore desire to be limited to the precise construction shown.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
2"
1. In an air brush, the combination with a needle for controlling the emission of
paint from the brush, of a thumb plate arranged to move in a path practically
parallel with the needle, and suitable mechanism intervening between said plate
and needle for imparting longitudinal motion to the needle upon the actuation of
the thumb plate, substantially as described.
2. In an air brush, the combination with a needle for controlling the emission of
paint from the brush, of a thumb plate, supporting an eye., a guide & engaging
said eye, and suitable mechanism intervening between said plate and needle for
imparting longitudinal motion to the needle upon the actuation of the thumb plate,
substantially as described.
3. In an air brush, the combination with a needle for controlling the emission of
paint from the brush, of a thumb plate arrauged to move in a path practically
parallel with the needle, and a back lever à adapted to be actuated by said thumb
plate, said back lever being adapted to move said needle longitudinally,
substantially as described.
4. In an air brush, the combination with a shell, of a needle for controlling the
emission of paint, a sleeve b to which the needle is secured, bearings in which said
sleeve is capable of longitudinal travel, a back lever h engaging said sleeve and a

page_text: thumb plate for actuating said back lever arranged to move in a path
practically parallel with the needle, substantially as described.
5. In an air brush, the combination with a needle for controlling the emission of
paint, a sleeve b secured to said needle, bearings engaging said sleeve for directing
it in a longitudinal direction, whereby the needle is relieved of frictional wear, and
means for moving said sleeve longitudinally, substantially as described.
6. In an air brush, the combination with a needle for controlling the emission of
paint, a sleeve b secured to said needle, a bearing sleeve fin which the sleeve b is
adapted to reciprocate, a cap screw upon sleeve f, a spring g tending to thrust
the sleeve band needle in one direction, and means for thrusting said needle and 1
sleeve in the other direction, substantially as described.
7. In an air brush, the combination with a valve pin placed within an opening
or passage provided in the brush for the admission of air thereto, a lever or equivalent
device for depressing the valve pin to permit or increase the flow of air, means for
restoring the valve pin, and a pin carried by said lever adapted to engage a slot
formed in the contiguous end of the valve pin, substantially as described.
8. In an air brush, the combination with a stem k carried by the brush, said stem
being provided with an opening or passage through which the air is adapted to be
passed into the brush, a valve pin l for controlling the supply of air, said pin having
its upper end projecting above the stem, said end being provided with a slot, a lever
or equivalent device for depressing the valve pin for permitting or increasing the
flow of air, a pin carried by said lever engaging said slot, and a spring for restoring
said pin, substantially as described.
9. In an air brush, the combination with a needle for controlling the emission of
paint, of a receptacle for the liquid paint carried by the brush through which the
needle passes, lever mechanism for imparting longitudinal movement to the needlo,
a double partition interposed between the paint receptacle and said lever mechanism,
whereby the aint is prevented from being drawn into the space occupied by the
lever mechanism, substantially as described.
I
Dated this ōth day of May 1897.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, W.C., Agents for the Applicant.