Патент USA US2040253

May 12, 1936.
' J. w. FITZ GERALD ‘
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2,040,253 -
AUTOMATIC PRIMER FOR INTERNAL COMBUSTION ENQINES
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Filed Maréh 12, 1934
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May 12, 1936.
1.1. w. FITZ GERALD
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2,040,253
AUTOMATIC PRIMER FOR INTERNAL ‘COMBUSTION ENGINES
Filed March 12, 1934
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2,040,253 _‘
Patented May 12, 1936
UNITED STATES
PATENT OFFICE "
2,049,253,
AUTOMATIC PRIMER FOR INTERNAL‘
.
COMBUSTION ENGINES
John w. Fitz Gerald, Milwaukee, will, 'assignor
to Briggs & Stratton Corporation, Milwaukee,
Wis., a corporation of Delaware
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Application March 12, 1934, Serial No. 715,136
6 Claims.
(01. 123-1875)
‘This invention relates to new and useful im
provements in automatic primers for internal
- combustion engines, and has as an object to ‘pro
vide an automatic priming device ‘which is con
trolled jointly by engine suction, and the thermal
condition of the engine.
'
ID, has an inlet ll connected to the supply line 8
by a pipe l2 and an outlet l3 connected by a
pipe I‘ to the intake manifold to afford a direct ,
communication between the supply line and the
manifold under certain conditions.
As best shown in Figures-3 and 4, the inlet ll
Another object of this invention is to provide ‘ leads to a transverse bore K5 in the bodyv l6
a priming device of the character described in
which the admission of priming fuel to the en
10 glue is controlled by two independent-valves, one
controlled jointly by engine suction and tempera
ture variations, and the ‘other’ controlled solely
by temperature changes.
of the device with which two lateral bores I1
and t8 communicate. Intermediate the length
of the body IS, the bores l1 and 18 are counter- 10
bored as at l9 and“, respectively, to de?ne
abrupt shoulders forming valve seats 2| and 22,
respectively.
_
Adjacent the valve seats, both bores I ‘l and I8 '
15 vide a priming device of the character described, , communicate with a cross bore 23, the opposite 15
ends of which are closed by plugs. At a medial
which is simple in constructionand easily ap
plied to any conventional type of internal com-5 .. point, the bore is connected with the outlet 13
A further object of this invention is to pro
bustion engine.
5
e
through 'a bore 24.
.
With the above and other objects in view which
will appear as the description proceeds, my in
vention resides in the novel construction, com
bination and arrangement of parts substantially
‘
The several bores formed in the body provide ~
two separate fuel passages from the inlet II to 20
the outlet ‘l3. These passages are independently
closed by needle valve members 25 and 26 oper
ating in the bores l9 and 20 for cooperation with
as hereinafter described and more particularly
de?ned by the appended claims, it being-under- , 'the valve seats 2! and 22, respectively.
‘The valve member 25 is controlled entirely 25
stood that suchv changes in the precise embodi
‘ment oi the hereindisclosed invention may be thermostatically. Its outer end projects through
made as come within the scope of the claims.’ a pocket 21 formed as a counterbore to the bore
In the accompanying drawings, I have illus 7 l9, and ‘has a stop ?ange 28 ?xed thereto, be‘
trated one complete example of the physical em
bodiment of my invention constructed according
to the best mode I ‘have so far devised for the
tween which and the bottom of the pocket 21,
a compression spring 29 is con?ned. , The spring 30
29 yieldably urges the valve member 25 to its 7
practical application of the principles thereof,‘ open position against the opposition of the spring
and in which:
v
Figure 1 is an elevation view showing part
tension ‘of a bi-metallic U-shaped member 30
having one end anchored to the body it as at St
35 of a carburetor and the manifolds of an internal . and its other end bifurcated to engage in an an- 35'
nular groove 32 in a head 33 ?xed to the extreme
combustion engine, and illustrating the applica
tion of this invention thereto;
,
Figure 2 is a side elevation view of the priming
device per se;
Figure 3 is a'longitudinal section view through
Figure 2_on the plane of the line 3-8;
Figure 4 is a section view taken through Fig
ure 3 on the plane of the line 5-4; and
Figure 5 is a section view similar to Figure 3,
45 but illustrating the valves in di?erent positions.
Referring now more particularly to theaccom
panying drawings in which like numerals indicate
like parts throughout the several views, the nu
meral 5 designates the carburetor of an internal
50 combustion engine supplied with fuel by a‘sup
ply line 5 and conducting a combustible mixture
to an intake manifold‘! through a riser 8. As
is customary, an exhaust manifold 9 is located
in juxtaposition to the intake manifold.
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The primer, indicated generally by the numeral
outer end of the stem of the valve member 25.
The disposition of the metals of the thermo
static member 30 is such that when the ambient
temperature is cold, the valve member is per- 40
mittedto be moved to open position by its spring
29, as shown in Figure 3, but as the temperature
rises, the thermostat 3B ?exes and brings its free .
end in toward the body it to gradually close
they valve member 25 against the action of the 45
spring 29. ’
The stem 31 of the other valve member 26'
extends outwardly through a bore 35, which forms
a cylinder for a piston 36 secured to the stem.
The outer end of the stem 31 is slidable in a 50
hole through a plug 38, which closes the end
of the cylinder bore 35.
Air bleeds 38' through -
the plug, permit the piston 36 to respondto
suction created within the cylinder bore through '
‘its communication with the intake manifold ‘I. 55
2.
2,040,253
To insure such communication between the cyl
inder bore and the manifold, the inner end 39
admission of fuel to the engine, engine suction
responsive means for closing one of said valves,
of the valve stem is polygonal in cross section
thermostatic means for opposing said engine suc
to at all times afford communication between
the cylinder bore 35 and the cross bore 23, which,
as hereinbefore noted, is in constant communi
cation with the intake manifold.
tion responsive means and operable to hold said
valve open when the ambient temperature is low
and in the absence of engine suction and to hold
the valve closed when the ambient temperature is
high even though engine suction ceases, a spring
for yieldably opening the other valve, and ther
The extreme outer end of the valve stem 31
has an annular groove 40 with which the bi
mostatic means opposing said spring and tend 10
strip 4| engages. The opposite end of the strip 6| ing to close said second designated valve as the
. is anchored to the body "5 by securing means 42. ambient temperature rises.
2. In combination with an internal combustion
The spring tension of the ‘thermostatic strip
10 furcated end of a second bi-metallic U-shaped
4| is su?ioiently light to permit engine suction
.15 acting upon the piston 36 to move the valve
member 26 to closed position just as soon as the
' engine becomes operative‘, but in the absence of_
engine suction, and while the ambient tempera
ture is low, the thermostatic strip‘ at holds the
20 valve member 26 in open position, as shown in
Figure 3.
‘
engine, an automatic priming device comprising
means providing a plurality of passages con
nested in parallel and adapted to'jointly supply
fuel to the engine, valves in said passages for
jointly controlling the admission of fuel to the
engine, engine suction responsive means for clos
ing one of the ‘valves, temperature actuated 20
means for opposing the suction responsive means
and for holding said valve open until a predeter
The operation of the device thus is as follows:
Assuming that the engine is cold, and the am
mined degree of ‘engine suction has been reached,
bient temperature of the thermostats likewise is said temperature actuated means also holding
low, the valve members 25 and 26 are conse ‘ said valve closed when a temperature of aprede 25
quently in open position as illustrated in Figure 3. termined high degree has been reached regard
During the starting of the engine, the suction less of variations in engine suction, and a second
built up therein is insufficient to move the valve temperature actuated means for controlling the
other valve.
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member 26 to closed position, so both valves re
30 main open to admit the maximum volume of‘
3. In combination with an internal combustion
auxiliary or priming fuel to the intake manifold. engine, an automatic primin'gI device comprising
Just as soon as the enginebecomes operative. a body having two fuel passages connected in
under its own power, the suction builds up to a parallel through which fuel may pass simultane-'
point su?icient to move the valve member“ to ously for admission to the engine, a valve for
35 closed position against the spring tension of ' the closing each passage, a piston connected with
thermostat 4|, by its- action upon the piston 36. one valve and responsive to engine suction for
closing the same, a spring for holding the other
The volume of priming fuel ?owing to the in
valve open, and temperature actuated means for
take manifold is thus materially reduced.
'I'hevalve member 25, however, does not close controlling the actuation of said valves by the
40 at this time, but remains in open position until piston and spring in accordance with the ambient .40
the temperature of the engine rises sufficiently to
?ex the thermostatic strip 30 by reason of its
temperature.
3
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~ 4. In combination with an internal combustion
engine, an automatic priming device comprising,
- proximity to the exhaust manifold, toward the
body of the priming device su?iciently' to over- ' a body having two fuel passages connected in
come the spring 29 and ‘move the valve member
parallel through which fuel may pass simultane 45
25 to closed position.
ously'for admission to the engine, a valve to close
,
. ~
While the valve member 25 is being moved to
each passage, 8. piston connected with one valve
closed position by its thermostatic strip 30, the and responsive .to engine suction for closing said '
thermostatic strip 4| is also being ?exed by the ‘ valve, a spring tending to hold the other valve
50 temperature rise to force its free end in toward
open, and independent bi-metallic members an
chored to said body and connected at their
engine is operating properly and normal oper
outer free ends with the valves for controlling
ating temperature has been reached, and the the actuation of the valves by said pistonv and
effective suction of the engine is momentarily spring. .
55 decreased as by suddenly opening the throttle,
5. In combination with an internal combustion
the valve member 26 will not be moved, being engine, an automatic-priming device, comprising
held in closed position by its thermostat 40.
a body having two fuel passages connected-in
. Obviously, when the engine cools off, after'be
parallel, a valve for closing each passage, a pis
ing stopped, both‘ valve members will again‘re
ton responsive to engine suction for closing one
60 sume their open positions.
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of said valves, spring means for yieldably hold so
ing the other valve open, and bi-metallic U
From the foregoing description taken in con
nection with the accompanying drawings, it will shaped strips anchored to the body at one end '
the, body I6. 01’ the device so that if after the
' be readily apparent to those skilled in :the art to
.which this invention appertains, that this in
vention aii'ords a novel and extremely simple,
fully automaticpriming device for internal com
‘ , bustion engines and that an exceptionally ?ne
and even control of the supply of primingfuel to
the engine, is had at all times.
70
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What I claim as my invention is:
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1. In combination with an internal combustion
engine, an automatic priming device comprising
means providing a plurality of fuel passages con
nected in parallel forconducting fuel to the en
75 gine, valves in said passages for controlling the
and connected at their outer free ends with the
valves for controlling the response thereof to said
piston and spring respectively. the bi-metallic
strip opposing the action of the piston holding
its valve open by its inherent resiliency when
the ambient temperature is low and until engine
suction exceeds a predetermined degree and hold
ing its ‘valve closed regardless of variations in
engine suction when the ambient temperature is
high, and the bi-metallic strip of the other valve
closing its valve against the action of the sp
as the ambient temperature rises.
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6. In combination with an internal combustion 75
2,040,258 r
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means providing two parallel fuel passages ior
whereby said valve is regulated Jointly by engine
suction and changes in the ambient temperature,
conducting fuel from a common source to the
engine, a valve in each of said passages for con
means for nulliiying any ‘affect engine section
might have on the other valve, and thermostatic
trolling the admission of fuel to the engine there
through, engine suction operated means for regu
means responsive to ‘changes in the ambient tem
perature acting in conjunction with said last
lating one of said valves, thermostatic means re
named means for regulating said other valve.
engine, an automatic priming device comprising
sponsive to changes in the ambient‘temperature
for opposing said engine suction operated means
‘Joan w. FITZ GERALD.