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Патент USA US2065144

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Dec, 22, 1936.
L. F. MILLER ET AL.
2,065,144 ^
TIMING MECHANISM
Filed April 25, 1935
' 2 sheets-sheet 1
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ATTORNEY@l ‘
Dec. 22, 1936.
L. F. MILLER x-:T Al.
2,065,144
TIMING' MECHANISM
~ Filed April 26, 1935
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Patented Dec. 22, 1936
2,065,144
UNITED 'STATES PATENT OFFICE
2,065,144
TIMING MECHANI SM
Leon F. Miller, Cleveland, and Robert W. Ellms,
Lakewood, Ohio, assignors to The Osborn
Manufacturing Company, Cleveland, Ohio, a
corporation of Ohio
Application April 26, 1935, Serial N0. 18,393
3 Claims. (Cl. 121-164)
This invention is directed to a timing mold
making method and mechanism particularly
adapted for use with fluid-pressure machinery,
and especially intended to govern automatically
5 the time of action of jolt machines and squeeze
machines, whether separate or combined, for the
making of sand molds in foundry work.
In the making of sand molds, it is customary
to jolt the mold after iilling in order to compact
10 the sand and a common practice is also to squeeze
the mold for the same purpose. Machinery is well
known in the trade either for jolting, or for
squeezing, and very frequently the two functions
are combined in a single machine which is gen
15 erally made with one cylinder for jolting and an
other for squeezing, the two cylinders being
nested. Compressed air is almost universally
used as a motive power for these mechanisms.
Inasmuch as it is highly advantageous for the
20 operator to keep his hands free to handle the
molds, the supply of air to the machine either for
jolting or for squeezing is usually controlled by a
valve which the operator opens by knee pressure
and holds open as long as he wishes the jolting or
25 the squeezing, as the case may be, to continue.
The present invention is of a character to
govern the supply of compressed air or other ñuid
pressure to such machinery so that all the oper
ator need do is open the valve, whereafter the
30 pressure will remain on for a predetermined
period and then automatically shut itself oiî, thus
controlling the number of jolting strokes or the
time the squeeze is held.
The purposes of this invention include adding
35 to the art a timing mechanism which will allow
operation as indicated for a definite time and stop
it at the end of that time, the timing mechanism
being of a construction which is accurate, reliable,
positive, compact, rugged, which can be easily and
40 accurately regulated and which is relatively sim
ple to manufacture.
ToI the accomplishment of the foregoing and
related ends, said invention, then, consists of the
means hereinafter fully described and particularly
45 pointed out in the claims.
The annexed drawings and the following de
scription set forthV in detail certain mechanism
embodying the invention, such disclosed means
constituting, however, but one of various me
50 chanical forms in which the principle of the in
vention may be used.
In the accompanying drawings:
ï Fig. 1 is apartly diagrammatic elevation illus
trating the piping and valve lay-out and the ap
.55 plication of the timing mechanism;
Fig. 2 is a transverse vertical section through
an automatic valve associated with the timing
mechanism;
Fig. 3 is a longitudinal mid-section through the
timing mechanism;
Fig. 4 is a section on the plane indicated at 4-4,
Fig. 3; and
Fig. 5 is a section on the plane indicated at 5-5,
Fig. 4.
The fluid for operating such mechanisms is 10
usually compressed air, and this speciñcation is
accordingly written designating compressed air,
although it will be understood that the apparatus
is of general application with any fluid under
pressure.
l5
In the general lay-out, Fig. 1, the timing mecha
nism as a whole, indicated by the reference char
acter I, is shown as bolted or otherwise secured
to part of the frame or cylinder 2 of a jolt or
squeeze or jolt-squeeze machine, although for sim- 20
plicity the invention will hereafter be referred to
in its application to a jolt machine.
A valve 4 herein shown as having a knee-actu
ated operating lever 6 is illustrated as attached to
another portion 2’ of the machine conveniently 25
accessible to the operator. Air reaches this valve
through a branch ‘I from an air main III. Beyond
the valve 4, the branch 'I is continued as at 'I' to
the valve cage 8 of the timer I, and another
branch, 9, runs from the timer to a diaphragm 30
Valve II on the air main I0. The diaphragm
valve Il controls flow of air to the jolt cylinder,
being connected thereto by a continuation III’ of
the main. Part of the piston P of the jolt or
squeeze mechanism (as the case may be) is shown 35
in Fig. l. A cut-off valve I2, ordinarily left open,
is illustrated as applied to the continuation I0’.
Before proceeding to the description of the tim
ing mechanism, the operation of the valve Il,
which is shown in detail in Fig. 2, will be eX- 40
plained as an aid to understanding the use of the
timing mechanism.
The valve II comprises a two-piece casing,
namely a body I3 and cover I4 having a flexible
diaphragm I5 secured therebetween. A disk I6, 45
carried by the upper side of the diaphragm, is
downwardly urged by its own Weight and by a
spring I'I. The valve body I3 includes an annular
air chamber I8 into which the main III leads, and
a central outlet I9 from which the continuation 50
IB’ goes to the jolt cylinder.
The valve cover I4 is hollowed, forming an air
chamber 2I of somewhat irregular shape, and a
central space receiving the spring I‘I and a stem
0f the disk I6, the stem being within the spring. I55
2
2,065,144
Air under pressure is applied by the branch 9 to
the upper surface of the diaphragm I5 and of
the disk I6. The air chambers I8 and 2| are con
nected by a bleed passage 22, constantly open,
fingers 45 of the rocker arm. The_long forward
finger 46 of the arm projects into the path of the
which passage includes a perforation in the dia
to open that valve.
phragm I5.
When the branch 9 is closed, leakage of air
through the bleed passage 22 builds up pressure
in the upper ‘chamber 2 I with the result that when
10 the pressure in the upper and lower chambers 2l
lower piston head 34 and in down position bears n
against the top of the stern 41 of the valve 21,
The rocker arm rear finger
48, much shorter, when down contacts the top of
the stem 49 of the valve 26, thus opening the
Valve. A spring 5I thrusting upon the rear of the
latch 44 below the pivot point, and seated in a
recess in the side wall of the valve cage 8, urges 10
and I8 is equalized there is a greater area ex ` the latch 44 counterclockwise and the rocker arm
posed to air pressure above the diaphragm than 42 clockwise. The latch 44 is shouldered at 52
below it, so» that the diaphragm descends. The and at 53 to bear selectively against the Valve
descending action is also aided by the weight of
15 the disk I8 and the pressure of the spring I1.
The diaphragm in descending seats on the top of
the outlet I9, thus cutting off I8 from I9 and
stopping flow of .air through the main I9, I 6’.
Relief of pressure in the upper chamber 2I
20 through opening the branch 9 by the timer, as
described hereafter, allows the pressure beneath,
in chamber I8, to raise the diaphragm, thus open
ing the main and supplying air to the jolt ma
- chine.
It is thus .apparent that the immediate
25 function of the timing mechanism in the illus
trated preferred embodiment is to cause the open
ing or closing of the upper air chamber 2 I.
»The timing mechanism per se is illustrated in
Fig. 3 in its normal position, not under air pres
cage wall at the top of the opening 24.
The inner tip of the latch 44 projects into the
path of the upper piston head 33. In the posi
tion of Fig. 3 the shoulder 52 holds the latch, and
the spring 5I is compressed. The travel of the
latch and of the rocker arm is between the full
Yand dotted line positions, as will be described in 20
connection with the operation of the apparatus.
The details of the plunger valves 26 and 21
include the two stems 49 and 41 respectively, each
suitably packed, each cone-shouldered at 54 to
close on a conical seat 55. Each valve is guided 25
by an enlargement 56 fitting the lower part of the
Valve chamber, and is urged up from below by
spring 51.
'
l The course of air through the valves is apparent
It comprises a
from Fig. 4, the valve there shown being the outer
cylinder 23 having the valve cage 8 secured to one
side. A piston reciprocates in the cylinder and by
one, 26.
. «_The operation of the mechanism is as follows:
its motion releases or sets a trigger mechanism
protruding into the cylinder through a side open
drawings, the jolt piston down, and a mold on
sure, ready but not operating.
35 ing 24.
Starting with the parts in the positions of the
The cylinder 23 is closed and domed at
the jolt table, the operator presses the knee valve
the upper end by a cap 25 into one side of the
top of which an air pipe 1”, which is a continua
tion of 1’, enters. The trigger mechanism actu
ates plunger valves 26 and 21 which open or close
40 the air branches 1’ and 9. In Fig. 3 the valve 26
>is 'open connecting the branch 1’ through the
pipe 1” to the cap 25, but there is no pressure
above the piston, because the valve 4 is closed.
A bleed valve 28, preferably a needle valve, is
placed in the top of the cap. An intermediate
horizontal baiile 29 extends somewhat more than
>half way .across the dome to protect the needle
valve 28 from oil, dirt, moisture, and foreign
matter generally, which would tend to clog it and
lever 6, thereby admitting air to the branch 1’.
so stop the action of the timer or decrease its
accuracy. A plug 36 closes the cylinder bottom.
In the preferred form shown this plug is centrally
hollowed as at 3| to receive a spring 32, normallyA
holding the piston in the upper position shown.
55
In the illustrative embodiment the piston is
double headed, the upper head 33 being thick and
solid, and the lower head 34 thinner and perfo
rated as at 35 for air escape. The two heads are
connected by a sleeve 36 of less diameter, also
60 perforated, as at 31, for air escape. A leather
packing 38 at the upper end of the piston is se
cured by the usual means such as a washer and
cap screw. The space below the piston head 33
is vented to the atmosphere through the open
Inasmuch as the valve 26 is open, the air so ad
mitted passes through the pipe 1" into the capl 25
thus moving the piston downward. Air will im
mediately begin to escape through the needle 40
valve 28 and bleed hole, but the rate of supply l'
is substantially greater than the rate of escape.
As the piston moves downward, the lower edge
ofthe head 33 trips the latch 44 off its shoulder
52, whereupon the rocker arm and latch are 45
moved to the dotted line position of Fig. 3 by the
spring 5I, the reduced diameter of the sleeve 36
permitting such movement.
The finger 46 thus opens the inner valve 21,
which in turn vents the branch 9 to the atmos 50
phere, relieving the pressure in the upper cham
ber 2I of the diaphragm valve, Fig. 2, and so open
ing that valve and admitting air from the main
I6 through the extension I0' to the jolt cylinder. .
The joltingvcontinues so long as the diaphragm
valve remains open. The same movement of the
rocker arm 42 to the dotted line position lifts the
iinger 48 from the'stem 49, allowing the spring
51 to close the valve 26, thus stopping the supply
of air through the branch 1’ and pipe 1” to the
cylinder 23. With the air supply oiî, the pressure
above the piston is relieved through the needle
valve 28, Vallowing the piston to rise by the pres
sure of spring 32, the time of rising being regu
65 ings 35, 31, 24, and ñnally out through a passage
lated by the setting ofthe needle valve.
39, Fig. 4, in the upper part of the valve cage 8.
The valve cage 8 houses the trigger mechanism
in its upper part and its lower part forms` the
body of both valves 26 and 21. Removable plugs
70 40 anda removable side plate 4I give access to
As the piston rises the lower head 34 pulls up
the inner end of the finger 46, thus restoring the
latch mechanism to the position of Fig. 3, allow
the cage interior.
The trigger mechanism comprises the three
fingered rocker arm 42 pivoted at 43, and a latch
44 of roughly triangular outline pivoted near one
.75 angle of its short base toa pair of upstanding
35
65
ing the valve 21 to close, and opening the valve 26.
Thus the branch 9 is closed and air flow through 70
the bleed passage 22, Fig. 2,V builds up pressure
above the diaphragm, shutting the diaphragm
valve and stopping the jolt action. At the same
time the valve 26 is opened, but this by itself is
not effective to start the jolt mechanism again be. 75
l 2,065,144
cause the valve 4 is now closed. The operator
held his knee on the lever 6 only momentarily.
In using our timer for jolt-squeeze machines it
is our preferred practice to use one timer for the
jolt air supply and another for the squeeze air
supply.
Other modes of applying the principle of our
invention may be employed instead of the one ex
plained, change being made as regards the mech
10 anism herein disclosed, provided the means stated
by any of the following claims or the equivalent
of such stated means be employed.
We therefore particularly point out and dis
15
tinctly claim as our invention:
1. In a pressure actuated timing mechanism, a
piston operable by fluid pressure in one direction,
means for returning said piston following release
of fluid pressure, an air dome above said piston,
an air supply connection to the air dome, a bleed
20 valve from said air dome, and a baffle within said
air dome shielding said bleed valve while per~
mitting flow of air thereto.
2. An automatic timing mechanism comprising
a cylinder, a piston movable in one direction
25 therein by fluid pressure, a spring in said cylin
der adapted to be compressed by said piston
movement and to move said piston in the reverse
direction, a valve operating unit adjacent said
cylinder, said unit comprising a lever adapted to
30 press selectively at opposite limits of its travel
upon one only of two self-closing plunger valves,
3
a spring urging said lever to one limit of its
travel, said lever protruding into the path of said
piston and movable by said piston against the
impulse of said spring to the other limit of its
travel, admission of air to said piston being con
trolled by one of said plunger valves, and a bleed
exhaust in said cylinder for compressed fluid
above said piston.
3. An automatic timing mechanism comprising
a cylinder, a piston movable in one direction 10
therein by fluid pressure, a spring in said cylin
der adapted to be compressed by said piston
movement and to move said piston in the reverse
direction, a valve operating unit adjacent said
cylinder, said unit comprising a lever adapted to 15
press selectively at opposite limits of its travel
upon one only of two self-closing plunger valves,
a spring urging said lever to one limit of its
travel, said lever protruding into the path of an
element of said piston and movable by said piston
against the impulse of said spring to the other
limit of its travel, a trip finger protruding into
the path of another element of said piston, said
ñnger being adapted to hold said lever against
the pressure of its spring during part of the 25
piston travel in one direction, admission of air
to said piston being controlled by one of said
plunger valves, and a bleed exhaust in said cylin
der for compressed fluid above said piston.
30
LEON F. MILLER.
ROBERT W. ELLMS.
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