Improvements relating to Air Brushes.
Year: 1899

page_text: Date of Application, 16th May, 1899-Accepted, 16th Sept,, 1899
COMPLETE SPECIFICATION.
Improvements relating to Air Brushes.
I, GEORGE CROYDON MARKS, of 18, Southampton Buildings, Chancery Lane,
London, W.C., Consulting Engineer and Chartered Patent Agent, (a communica-
tion from abroad by Henry Joshua Thayer and Charles Hibbard Chandler,
Manufacturers, both of 146, Wasbash Avenue, Chicago, State of Illinois, United
- States of America), 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 brushes of the type generally known as "air brushes,"
in which liquid pigment is distributed by means of air under pressure.
devices are illustrated in, the British Patent No. 6466 of 1897.
Such
My invention has for its object the improvement of the mechanism of air
brushes, whereby the adjustment thereof may be effected by those not familiar
with the mechanism of air brushes without danger of injuring the delicate parts,
and also has for its object the provision of improved mechanism whereby the
degree of fineness of the spray as it issues from the brush may be readily adjusted.
This mechanism consists, in the preferred embodiment of the invention, of a
tip or nozzle having threaded engagement with a body portion of the brush,
the inner wall of the tip forming a wall of a conical passage through which
the air is conveyed under pressure. By the adjustment of this tip longitudinally
of the needle, the size of the passage may be adjusted and thereby the degree of
fineness of the spray of pigment controlled.
Another feature of the invention consists in providing a reservoir for the
pigment, the capacity of which may be adjusted according to. the amount of
pigment to. be used in a given time, and consists in providing a reservoir pre-
ferably of cylindrical shape having separable sections for enlarging or decreasing
the capacity of the reservoir.
. A third feature of my invention consists in a stationary sleeve surrounding
the needle and serving at its end portions snugly to fit the needle to guide the
same accurately in its longitudinal travel, the portion of the sleeve intermediate
between its ends being enlarged to form a passage or space around the needle
in which any ink or pigment that may find its way backward from the point of
the needle may be received, to prevent its being passed to other working parts
and injuring the same. The ink or pigment dries within this space and when
the brush is to be cleaned may readily be removed therefrom.
In the brushes as heretofore constructed; an operating finger lever was em-
ployed to impart longitudinal movement to the needle through the agency of
a back lever. This same finger lever also served to actuate the valve for
controlling the supply of air under pressure and in its operation for the latter
purpose would have constant frictional contact with the back lever, whereby the
engaging portions of the finger and back levers became worn. In the operation
of air brushes, it is only necessary to shift the needle during a very small fraction

page_text: of the time, as the needle should be so adjusted as never entirely to close the
conical passage through which the pigment is being conveyed.
The invention in this connection provides for a construction wherein the part
interposed between the finger lever and the needle for shifting the same longi-
tudinally is normally out of contact with the said finger lever, slight lost motion
between the finger lever and the said part being provided for when the finger
lever is to actuate the needle, so that the finger lever may perform its function
of controlling the supply of air without wearing away the back lever or portion
for actuating the needle.
Another feature of the invention consists in improved mechanism for adjusting
the initial position of the needle with reference to the nozzle by the user, which
may thereby be accomplished without danger of injuring the delicate parts of
the brush.
I will explain the foregoing and additional features of my invention by
reference to the accompanying drawing, illustrating the preferred embodiment
thereof, in which
Figure 1 is a longitudinal section of the brush with parts thereof in elevation;
Figure 2 is an elevation of a portion intervening between the finger lever and
the needle for shifting the needle longitudinally;
Figure 3 shows the finger lever and the valve stem in end elevation, these
parts being shown disunited;
Figure 4 is a longitudinal elevation of my improved device for effecting the
initial adjustment of the needle;
Figures 5, 6 and 7 are respectively side, back and front views of a tapered
slotted sleeve for clamping the needle;
Figure 8 is a side elevation of a plug having a threaded stem for clamping
the tapered sleeve about the needle;
Figure 9 is a side elevation of the adjustable nozzle;
Figure 10 is a side elevation of a part of the body portion in which the
nozzle is inserted;
Figure 11 is a cross-sectional view on line 11-11 of Figure 10;
Figure 12 is a cross-sectional view on line 12-12 of Figure 1.
Like letters indicate like parts throughout the different figures.
In the body portion a, which is preferably metallic, is provided a receptacle
for the pigment made up of separable cylindrical sections 6 b. The pigment
may issue from this receptacle or reservoir through an axial bore in the portion c,
a continuation of which bore is formed by the interior of the sleeve d and the
tapered tip upon the front end thereof. The needle e passes through the bore,
the conical end of the needle serving to control the size of the conical passage
in said tip and thereby the quantity of ink to be emitted through the nozzle.
A nozzle f, provided with a conical bore surrounds the tip upon the sleeve d,
the portion of the nozzle directly surrounding the said tip presenting a conical
wall to said tip, whereby a conical passage is provided through which air is forced
under pressure, as will be described. The inner end of the nozzle f preferably
has threaded engagement with the portion c, whereby the adjustment of the
nozzle toward or from the said tip may be effected to control the size of the
conical air passage. Other means may be emploved for effecting the longitudinal
adjustment of the nozzle.
To make the spray coarse, the nozzle f is screwed in; to obtain a finer spray,
the nozzle is unscrewed. The adjustment is delicate, three or four turns of the
nozzle marking the preferred limit of adjustment.
An annular space g is provided between the portion c screwed into the portion a
and the latter portion, this annular space having communication with the conical
air passage through an intervening cylindrical passage and three small holes,
as shown in Figures 1 and 11. An air duct communicates between the passage g
and the controlling air valve, the operation of which is similar to that described
in the specification before referred to. The stem 7 of the air valve in the present

page_text: sleeve & surrounding a reduced lower extension of the stem h, the spring surroun
pivoted to the finger lever i, whereby the shoulder
ing said sleeve and the nut for securing the spring in place, may all readi
be removed without causing the displacement of the valve steni and breaking th
5 connection between the same and the finger lever when access is desired to th
interior parts. This construction, I believe to be novel, as heretofore when acces
was had to the valve parts a disengagement was sure to occur between the finge
lever and the valve stem, which engagement is difficult to re-effect, on account o
the small construction of the parts.
10
10
The finger lever
through a longitudinal slot and is bifurcated at its lower portion to enclose the
provided with a knurled finger plate. The lever extend
needle and the sleeve m surrounding the same.
engagement with the body portion a at the rear of the reservoir b, the tube or
The sleeve m has threaded
sleeve passing through and terminating at the front wall of the reservoir. The
15 portion of the sleeve within the reservoir is of reduced diameter to afford
additional space for the pigment. The interior portion of the sleeve intermediate
between its ends is enlarged to provide a space to receive the pigment that may
travel back along the needle. The sleeve is stationary, affording elongated bear-
ings at its ends for accurately guiding the needle in its longitudinal travel.
To actuate the needle, I provide a portion n, preferably in the form of a' sleeve,
surrounding the tube, a suitable connection (preferably that hereafter to be
described) being provided between the said sleeve or needle-actuating portion
and the needle. A rearward tubular extension of the portion n forms a spring
barrel, in which a coiled spring o is placed; this spring engaging at its forward
end an interior annular shoulder on the portion n and at its other end an adjust-
ing nut or sleeve having threaded engagement with the tube m, this nut
being employed for the purpose of adjusting the tension of the spring. The
sleeve is longitudinally movable and is preferably prevented from rotating by
means of a lugg upon the same, engaging a corresponding recess in the shell of
the brush. The nut i being stationary, the spring o tends to move the sleeve n
forward. The forward movement of the sleeve n is limited by adjusting nuts r
engaging a threaded portion of the said sleeve, the said nuts limiting the forward
motion of the sleeve by their engagement with an opposing shoulder within the
shell of the brush. By proper adjustment the sleeve may be prevented from
having engagement at its forward end with the lever when the said lever is
merely employed to actuate the air valve, whereby undue wear between the said
sleeve and lever is prevented, a very slight lost motion being preferably provided
for when the said lever is to actuate the sleeve n to effect longitudinal movement
of the needle. In order that the initial position of the needle may be adjusted
by the user, I connect the needle with the sleeve or needle-shifting portion n
by a tubular portions, which is provided with a ribbed surface, to which the finger
of the operator may have access through a slot t in the shell of the brush. The
leeve s has threaded engagement with a threaded portion of the sleeve n, whereby
he sleeves may be adjusted longitudinally of the sleeve n to effect the desired
nitial adjustment of the needle. The nuts prevent the needle from being
djusted too far forward, but the rearward adjustinent of the needle may be as
reat as desired to increase the size of the conical passage directly surrounding
he tip of the needle at the nozzle of the brush through which the pigment is
mitted.
The sleeve s is provided with a rearward extensionu, having a conical seat
r a slotted, tapered or conical sleeve having a bore to fit the needle.
ving a threaded extension screws into the end of the extension against the
posing face of the sleeve or' plug t, the said plug serving to clamp the sleeve
A cap w
rmally in place between the conical wall of the sleeve and the needle, whereby
e needle is securely clamped in position. By providing the tapered sleeve and
e corresponding tapered engaging surface in the extension a clamping means
provided which accurately' centers the needle. The needle of an air brush

page_text: has to be frequently removed in order to keep it clean, and by means of my con-
struction this is readily accomplished, simply by removing the handle of the
brush and unscrewing the portions and s. By the provision of said cap and
sleeve, wear between the parts clamping the needle in place is compensated for.
It will be apparent to those familiar with the art of air brushes that my con-
struction herein presents many novel and useful features by which many defects
heretofore existing are removed, and, while I have herein shown and described
a preferred form of brush constructed in accordance with my invention, I do not
wish to be limited to the precise features 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:
1. In an air brush, the combination with a portion provided with a passage
for conveying the pigment to the point of application, of a reservoir for the
pigment having communication with said passage, the said reservoir being
formed in separable sections, whereby the capacity of the reservoir may be readily
adjusted, substantially as described.
2. In an air brush, the combination with a portion provided with a passage
for conveying the pigment, of a needle inserted within the said passage for
controlling the flow of pigment, means for effecting the longitudinal movement of
the needle, and a fixed sleeve surrounding the needle and at its ends snugly
enclosing the needle properly to align the needle and guide the same in its longi-
tudinal travel, substantially as described.
3. In an air brush, the combination with a portion provided with a passage
for conveying the pigment, of a needle inserted within the said passage for
controlling the flow of the pigment, means for effecting the longitudinal move-
ment of the needle, and a fixed sleeve surrounding the needle and at its ends
snugly enclosing the needle properly to align the needle and guide the same in
its longitudinal travel, the intermediate portion of the bore of the said sleeve
being enlarged to gather particles of the pigment that may be drawn back along
the needle, substantially as described.
4. In an air brush, the combination with a portion provided with a passage
for conveying the liquid pigment to the point of application, of a needle for
controlling the flow of the pigment, an air passage for conveying air under
pressure to effect the flow of the pigment, a valve for controlling the supply of
air under pressure, a finger lever for effecting the operation of the said valve,
and mechanism intervening between the said finger lever and the needle for
effecting, through the agency of said lever, the operation of the said needle, the
said mechanism normally being out of engagement with the gnger lever, the said
lever being brought into engagement with the said mechanism when the needle
is to be actuated, substantially as described.
}
5. In an air brush, the combination with a portion having a passage for
conveying the liquid pigment, a second passage being provided for conveying
air under pressure to effect the flow of the pigment, of a needle within the first
aforesaid passage for controlling the flow of the pigment, means for effecting the
longitudinal movement of the said needle, a valve for controlling the supply of
air under pressure, the said valve having a valve stem h, and a finger lever i
bifurcated at its lower end, the bifurcated end of the lever having permanent
pivotal connection with the said valve stem, the said needle passing between the
bifurcated portions of the finger lever, the said finger lever being adapted to
co-operate with the aforesaid means to effect the longitudinal movement of the
needle and to move the valve stem, substantially as described.
6. In an air brush, the combination with a portion provided with a passage
for conveying liquid pigment, of a needle in the said passage for controlling the
flow of the pigment, a finger lever for moving the needle longitudinally
a sleeve n surrounding the needle, a second sleeves having threaded engagement

page_text: of a sleeve surrounding the needle and having a tapered se
a slotted plug having a bore for enclosing the needle, and means for forci
the said plug between the seat and the needle, substantially as described.
15. In an air brush, the combination with a needle for controlling the flo
of the pigment, of a sleeve surrounding the needle and having a tapered sea
a slotted plug having a bore for enclosing the needle, means for forcing t
said plug between the seat and the needle, and a cap screw for engaging th
slotted plug and forcing the same into firm engagement with the said seat an
needle, substantially as described.
16. In an air brush, the combination with a sleeve or portion having
passage for conveying the pigment, the said sleeve being provided with
tapered tip provided with a tapered bore forming a continuation of the aforesaid
passage, the said tip also having a tapered exterior surface, of a nozzle f affording
a tapered air passage between the interior wall thereof and the said tip, the
said nozzle being longitudinally adjustable, substantially as described.
17. In an air brush, the combination with a sleeve or portion d having a
passage for conveying the pigment, the said sleeve being provided with a tapered
tip provided with a tapered bore forming a continuation of the aforesaid passage,
the said tip also having a tapered exterior surface, of a nozzle f affording a
tapered air passage between the interior wall thereof and the said tip, the said
nozzle being longitudinally adjustable, and a needle provided in the passage
for conveying the pigment, substantially as described.
18. In an air brush, the combination with a sleeve or portion d having a
passage for conveying the pigment, the said sleeve being provided with a tapered
tip provided with a tapered bore forming a continuation of the aforesaid passage,
the said tip also having a tapered exterior surface, of a nozzle f affording a
tapered air passage between the interior wall thereof and the said tip, the
said nozzle being longitudinally adjustable, a needle provided in the passage for
conveying the pigment, and means for effecting the longitudinal movement of
the said needle, substantially as described.
19. In an air brush, the combination with a portion having a passage tapered
at the forward end, of a part e within the said passage between which and the
wall of said passage the pigment is adapted to be conveyed, and a nozzle f
surrounding the said portion and affording a passage for conveying air under
pressure between the same and the said portion, the said nozzle being adjustable 3
longitudinally to vary the size of the said air passage, thereby to regulate the
spray, substantially as described.
20. In an air brush, the combination with a portion having a passage tapered
at the forward end, of a needle within the said passage between which and the
wall of the said passage the pigment is adapted to be conveyed, a passage 4
surrounding the said portion for conveying air under pressure, and means for
adjusting the size of the said passage to regulate the spray, substantially as
described.
21. In an air brush, the combination with a portion having a passage for
conveying the liquid pigment, the said portion being surrounded by an air 45
passage adapted to convey air under pressure to effect the flow of pigment
through the said passage, of means for adjusting the size of the said air passage
to regulate the spray, substantially as described.
22. In an air brush, the combination with a portion having a passage for
conveying the pigment, of a second portion surrounding the aforesaid portion 50
and separated therefrom by a space into which air under pressure may be forced
or effecting the flow of pigment through the said passage, the said second portion
being adjustable to vary the size of the said air passage, substantially as described.
23. In an air brush, the combination with a portion having a passage for
igment, of a nozzle enclosing said portion, a space intervening between the 55
aid nozzle and portion for conveying air under pressure, the said nozzle being
djustable to vary the size of the said air passage and thereby the spray, sub-
tantially as described.

page_text: with the sleeve n and being thereby adjustable longitudinally of the same, the
sleeve s being secured to the needle, while the sleeve n is adapted for engagement
with the finger lever, substantially as described.
7. In an air brush, the combination with a portion provided with a passage
for conveying liquid pigment, of a needle in the said passage for controlling
the flow of the pigment, a finger lever for moving the needle longitudinally, and
a part n secured to the needle and adapted to be engaged directly by the finger
lever to effect the longitudinal movement of the needle, the said part n being
adjustable longitudinally with respect to the needle and the said finger lever,
whereby the initial set of the needle may be adjusted and proper lost motion
between the finger lever and the part provided for to prevent useless wear between
these parts, substantially as described.
8. In an air brush, the combination with a portion provided with a passage for
conveying liquid pigment, of a needle in the said passage for controlling the
flow of the pigment, a finger lever for moving the needle longitudinally, a sleeve n
surrounding the needle and adapted at one end to engage the finger lever and
united at the other end with the needle, and means for effecting the longitudinal
adjustment of the sleeve n with relation to the needle and the finger lever, sub-
stantially as described.
9. In an air brush, the combination with a portion provided with a passage for
conveying liquid pigment, of a needle in the said passage for controlling the
flow of the pigment, a finger lever for moving the needle longitudinally, a sleeve n
surrounding the needle and adapted at one end to engage the finger lever and
united at the other end with the needle, means for effecting the longitudinal
adjustment of the sleeve with relation to the needle and the finger lever, and
means for preventing the rotation of the sleeve n, substantially as described.
10. In an air brush, the combination with a portion provided with a passage
for conveying liquid pigment, of a needle in the said passage for controlling.
the flow of the pigment, a finger lever for moving the needle longitudinally, a
sleeve surrounding the needle and adapted for engagement at one end with
the finger lever, and a second sleeve s also surrounding the needle and secured
thereto, the sleeves having threaded engagement with the sleeve and being
adjustable upon the said sleeve to effect the desired initial set of the needle,
substantially as described.
11. In an air brush, the combination with a portion provided with a passage
for conveying liquid pigment, of a needle in the said passage for controlling
the flow of the pigment, a finger lever for moving the needle longitudinally, a
sleeve surrounding the needle and adapted for engagement at one end with
the finger lever, a second sleeve s also surrounding the needle and secured
thereto, the sleeves having threaded engagement with the sleeve and being
adjustable upon the said sleeve to effect the desired initial set of the needle,
and means for effecting the adjustment of the sleeve » longitudinally of the needle,
substantially as described.
12. In an air brush, the combination with a portion provided with a passage
for conveying liquid pigment, of a needle in the said passage for controlling the
flow of the pigment, a finger lever for moving the needle longitudinally, a
sleeve surrounding the needle and adapted for engagement at one end with
the finger lever, and a second sleeve s also surrounding the needle and secured
thereto, the sleeves having threaded engagement with the sleeve and being ad-
justable upon the said sleeve to effect the desired initial set of the needle, a slot or
opening being provided in the casing of the brush to permit access to the sleeves.
to effect its longitudinal adjustment, substantially as described.
13. In an air brush, the combination with a needle for controlling the flow of
the pigment, of a sleeve surrounding the needle, and having a tapered seat, a
plug having a bore for enclosing the needle, and means for forcing the said plug
between the seat and the needle, substantially as described.
14. In an air brush, the combination with a needle for controlling the flow

page_text: 24. In an air brush, the combination with a reservoir for containing the
pigment and having an outlet, of a nozzle enclosing the said outlet, an air passage
being provided between the interior wall of said nozzle and the said outlet for
conveying air under pressure, the said nozzle being adjustable to vary the size
of the said air passage and thereby the spray, substantially as described.
25. In an air brush, the combination with a portion having a passage for
conveying the pigment, of a second portion separated from the aforesaid portion
by a second passage for conveying air under pressure, and means for varying
the size of said air passage, substantially as described.
26. In an air brush, the combination with a portion provided with a passage
for conveying the pigment, a second passage being provided adjacent to the
outlet of the aforesaid passage for conveying air under pressure, of means for
varying the second passage to vary the spray, substantially as described.
Dated this 16th day of Mar 1900.
MARKS & CLERK,
18, Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and 25, Cross Street, Manchester,
Agents.