Apparatus for Mixing Air and Gas.
Year: 1896

page_text: Date of Application, 14th Apr., 1896-Accepted, 23rd May, 1896
COMPLETE SPECIFICATION.
Apparatus for Mixing Air and Gas.
I, JOHN MURRAY MITCHELL of 35 Wall Street, New York, in the United
States of America, Lawyer, 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 :-
This invention relates to air and gas mixers. It has for its object a device
whereby air and gas can be mixed in any desired proportions. This device consists
primarily of two compressors adapted respectively to force air and gas into a
common receptacle in such a manner as to be thoroughly mixed. These co-
pressors are operated at the same speed, and the quantities of air and gas are
regulated without changing the speed of the compressors, by moving certain valves,
which control ports of each compressor.
In the accompanying drawings, in which similar letters of reference designate
corresponding parts
and
Figare is a longitudinal section of a mixing device according to this invention,
Figure 2 is a transverse section.
A and B are the chambers in which the air and gas compressor pistons respectively
operate. They are shewn as cylinders, which with their pistons are of exactly the
same construction, only varying in size. As the description of one can be applied
equally to the other, the chamber A and its piston will be described.
1 is an inlet port and 2 an outlet port, enlarged at their inner ends by recesses 3,
which extend in opposite directions. Within the chamber A is fitted a compressor
piston whereby air is drawn into the chamber through the port 1 and expelled
through the port 2, mechanism being provided whereby the amount of air can be
regulated as desired. As shewn, the compressor piston consists of the cylindrical
body 4 eccentrically mounted within the chamber A, on the shaft 5 suitably
journaled in the sides of the chamber, and the sliding blades 13. The body 4 is
in contact with the inner periphery of the.cylinder A along one line.
Within the body 4 the chamber 15, has at opposite sides slots 12. On each
side of the chamber 15 there is fitted a sliding blade 13, having an arm 14, and
passing through a slot 16 in the side of the chamber. A spring 45 connected with
the body 4 and the arm 14 urges the blade 13 outwards and presses its outer edge
against the inner surface of the chamber A.
The amount of air is regulated by mechanism which will now be described.
Each sliding blade 13, has through it a port 17 which can be closed or throttled
more or less by a sliding valve 18 which rests against the blade and projects with
it through the slot 12. The valve 18 has an arm 19 with which is connected a
spring 20, fastened to the end wall of the chamber 15. This spring urges the valve
outwards so as to close the port 17. The shaft 5 on which the piston body 4 is
mounted is tubular. On the shaft between the sides of the piston-body, the conical
boss 8 is fitted, it has a lug 9 which passes through a longitudinal slot in the
shaft 5, and engages a screw spindle 10, which is mounted in bushings in the end of
the hollow shaft 5 and has at its one end a hand wheel 11. By turning the hand
wheel, and screw spindle 10, the conical boss 8 can be moved towards either hand.
An arm 12 projecting laterally from the inner end of the sliding valve 18 is
pressed by the spring 20 against the conical boss 8 so that by moving the conical
boss, the valve can be moved to cover the port 17 of the blade 13 more or less as

page_text: may be desired. The blade 13 has at its outer end a projection 46, which engages
with the end of the valve 18, to withdraw it along with the blade into the recess 15.
In the opposite side of the recess there is a similar sliding blade, and valve.
The inlet port 1 of the chamber A, is connected to a pipe 25 for conducting air
to the chamber, and the inlet port of the chamber B is connected to a pipe 26 for
conducting gas to the chamber B. The outlet port 2 of the chamber A is con-
nected to a suitable pipe 27 for carrying off the compressed air and, the outlet port
of the chamber B is connected to a pipe 28 terminating within the pipe 27 in a
nozzle 29 by which a current of compressed gas is injected into the current of
compressed air.
The compressor-pistons are caused by any suitable motor to revolve at the same
speed.
The operation of the device is as follows:-As the compressor-pistons rotate the
blades 13, are alternately pressed into the piston-body 4, and forced out of it, their
outer ends always remaining in contact with the inner surfaces of the cylindrical
chambers A and B respectively..
The quantities of gas and air mixed can be regulated by turning the spindle 10,
so as to move the conical boss 8 to separate more or less the arms 12, and
consequently the sliding valves 18, to which they are attached.
When the valves are moved quite out the compressor operates to its full
capacity. By drawing in the valves so as to open more or less the ports 17, the
capacity of the compressor is diminished, as a certain amount of air, which would
otherwise be forced, can escape through the ports.
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. Apparatus for mixing air and gas, constructed and operating substantially as
described with reference to the accompanying drawings.
2. In the apparatus above referred to, a pair of cylindrical compressor-chambers
each having within it a rotating eccentric cylinder making contact with its internal
surface along one line, an inlet port on the one side and an outlet port on the other
side of this line of contact, a pair of blades sliding through slots of the eccentric
cylinder, their outer edges being pressed by springs against the internal surface of
the chamber, substantially as described.
3. For regulating the delivery of the compressor, ports through the sliding
blades governed by valves sliding along the blades urged radially by springs in the
one direction and moved in the other direction by a conical boss caused to slide
along the eccentric shaft by an adjusting screw, substantially as described.
Dated this 14th day of April 1896
ABEL & IMRAY,
Agents for the Applicant.