close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2135858

код для вставки
TEMPERATURE CONTROL ÍÄECHANISM
Filed June 2°, 1957
Patented Nov. 8, 1938
2,135,858
UNITED STATES PATENT OFFICE
2,135,858
TEMPERATURE CONTROL MECHANISM
Robert H. J. Starsmeare, Orillia, Ontario, Can
ada, assignor to Tudhope Metal Specialties
Limited, Orillia, Ontario, Canada.
Application June 28, 1937, Serial No. 150,768
11 Claims.
This invention relates to thermostatically con
trolled mechanism for use with electric. heating
apparatus to switch a heating element on or off
as may be required to attain and maintain a pre
5 determined temperature in the apparatus, and
myobject is to` devise mechanism of this character
which will be cheap, simple and reliable.
I attain my object by providing a lever pivoted
on a thermostatically actuated arm journalled
i0 on a suitable stationary part. A switch arm nor
mally tending to close a heating circuit is so con
nected with the lever at a point in alinement
with the axis of the journal of the arm that, when
_ the lever is rocked on its pivot, the switch arm
(Cl. 20o-138)
gages a stop 8 on the arm 4 to normally position
the projection 'l as aforesaid and to limit the
rotary movement of the lever in one direction of
rotation on its pivot.
A ñxed contact S is carried by a bracket I0 '5
secured at II to a block I2 of insulating material.
The latter is secured by screws I3 to the plate I
and is provided with terminal bolts I4, I5. One
of the bolts is connected by a conductor I6 with
the bracket I0. A movable contact I'I is` carried 10
by a switch arm I8 which normally maintains
its Contact Il in electrical engagement with the
ñxed contact 9. Preferably the switch arm I8
is rigid and is constantly urged to maintain its
contact engaged with the fixed contact by a U 15
shaped spring frame I9. The frame I9 is pro»
l” will be moved to open the circuit. As the tem
perature increases in the apparatus, the arm is
moved to carry the lever into engagement with
Vided with a lug 2D for securing it to the block
an adjustable regulator which causes the lever
to rock relative to the arm and break the circuit
of the switch arm I8 which carries the contact
when the temperature reaches the point indicated
by the regulator. As the temperature in the ap
paratus drops, the movement of the arm is re
versed and when the lever moves out of engage
ment with the regulator, the switch is again per
mitted to close. Thus the switch is alternately
opened and closed as the temperature in the ap
paratus rises and falls respectively whereby
the temperature is maintained substantially at
the point set by the regulator.
30
The invention is hereinafter more fully de
scribed and is illustrated in the accompanying
drawing in which
Fig. 1 is a front elevation of my control mech
anism showing the switch for the heating circuit
35 closed;
Fig. 2 a similar view showing the switch
opened;
Fig. 3 a section on the line 3-3 in Fig. 1; and
Fig. 4 a plan View of the switch arm and its
«10 pivotal connections.
In the drawing like numerals of reference in
dicate corresponding parts in the diiierrent
figures.
I is` a supporting plate for the various parts
«i5 and may be secured to any part of a wall or the
top of an electrically heated oven. Carried by
the plate I is a thermostatic element 2 of known
type which requires no detailed description. To
the rotatable spindle 3 actuated by the thermo
50 static element is secured an arm 4. A lever 5
is pivoted at 6 intermediate its ends on the arm
I2 and with the arms 2| and 22.
'I'he free end
I 'I' extends through an opening in the arm` 2| 20
and the other end oi the switch arm is increased
in width and has a knife-edge fulcrum against
the inner side of the arm 2I on each side of the
opening and a similar fulcrum against the adja
cent end of a toggle member 23 which has a knife- ~ -
edge fulcrum on the inner side of the other arm
22 of the frame I9.
The frame I9 maintains a spring tension
against the end of the toggle member in the
direction of its length and the various fulcra
switch arm I8 is normally disengaged from the
back-stop and its contact I‘I is normally engaged
with the contact 9. The back-stop 24 is adjust
able in a bracket secured to the block l2 and
is so adjusted relative to the fixed contact 9 that
the toggle cannot be moved over center.
The toggle member 23 may be connected by
a piece of insulation 25 and a spring 26 with the
projection 'l on the` lever 5 whereby the latter,
when rocked relative to the arm 4, causes the
toggle member to move the switch arm contact
I'I out oi engagement with the ñxed contact. The
other terminal I5 is connected by a conductor 21
with the frame I9 so that a circuit including the
lead-ins 28 will be broken when the contacts are
5
separated.
An adjustable regulator comprising a pivoted
abutment member 29, a cam 30, spindles 3I, 32 En
4. `One end of the lever is provided with a lateral
connected by a collar and set screws 33, a knob
34 having an indicator 35 and a calibrated scale
projection 1 which is normally positioned sub
stantially in alinement with the axis of the spin
closing of the circuit 28. - The abutment mem
56 dle 3. The otherend of the lever normally en
0
and a back-stop 24 are so arranged that the
36 is provided for controlling the opening and
ber 29 is provided with a shoulder 3l adapted 55
2
2,135,858
to be engaged by a lug 38 on the end of the
lever 5 remote from the projection l.
As the temperature rises, the arm 4 moves
the lug 38 towards the shoulder 31 on the abut
ment member 29 which is held from movement
by the cam 30. The continued movement of
the arm and lever 5 as a unit results in the lug
38 engaging the shoulder 31 which causes the
lever to rock on its pivot 6 away from the stop 8.
The projection 'I is thus moved out of aline
ment with the axis of the spindle 3 to tension
the spring 26 and cause the movable contact
l1 to be moved out of engagement with the fixed
contact 8. The heating circuit is thus broken
but the temperature of the oven may rise slightly
for a short period oí time and, if so, the spring
26 will permit the arm 4 and pivot 6 to move
relative to the lever lug 38 which is held from
a continuing movement by its engagement with
the shoulder 37. When the temperature of the
oven drops suñiciently to permit the lever 5 to
return to its normal position the circuit will
be again closed until the temperature of the
oven reaches the point set by the indicator 35
on the scale 36.
circuit will be broken when the lever ls rocked
on its pivot.
3. Mechanism as set forth in claim 1 in which
the connecting means includes a spring so that
the arm is free to continue its turning move
ment after the lever has been rocked to cause
the circuit to be opened.
4. Temperature control mechanism compris
ing a thermostatically actuated arm mounted to
turn on an axis; a lever pivoted on the arm,
the pivot of the lever being offset relative to
the said axis; a pivoted abutment member
adapted to be engaged by the lever to cause it
to rock relative to the arm; a regulator for
iimiting the movement of the said member in
one direction, the regulator being adjustable to
vary the distance through which the arm must
move before the lever engages the abutment
member; a switch arm normally closing a cir
cuit; and means for connecting the lever, at a ~
point substantially in alinement with the said
axis; and the switch arm to move the latter to
open the circuit when the lever is rocked on
its pivot.
5. Temperature control mechanism compris- l
Referring to Fig. 3 it will be noted that the
cam 3S is so shaped that the higher the tem
perature desired in the oven, the greater the
unitary movement of the arm 4 and lever 5 be
fore the abutment member 29 is engaged by the
lever. Referring to Figs. 1 and 2 it will be
ing a thermostatically actuated rotatable spin
seen that the cam 30 engages the abutment
at a point in alinement with the axis of the spin
dle, with the switch arm so that the latter will
be moved to open the circuit when the lever is
rocked as hereinbefore set forth.
member near its pivot 39 which enables the mem
ber to be iinely adjusted over a wide range with
35 a minimum movement of the adjusting mecha
nism. If the device is used in a vertical posi
tion, a spring 40 may be employed to hold the
member 29 in engagement with its cam 3D. This
dle; an arm secured to said spindle; a lever piv
oted on the arm; an adjustable regulator against
which the lever is moved to cause it to rock
relative to the arm; a switch arm normally clos- ,rf
ing a circuit; and means for connecting the lever,
6. Temperature control mechanism comprising
a thermostatically actuated arm mounted to turn
on an axis; a lever pivoted on the arm; an ad
is not important, however, because the shoulder
justable regulator against which the lever is
31`wil1 not drop below the lug 38 and the Weight
oí the member 2S is not sufficient to affect the
moved by the arm to cause it to rock relative
to the arm; a ñxed contact; a switch arm carry
ing a movable contact; means tending to move
the switch arm so that its contact normally en
gages the ñxed contact; and means connected
correct operation of the spindle 3 by the thermo
static element.
If desired a pointer and scale device could
45 be readily connected with or operated from the
spindle 3 for indicating the temperature of the
oven. It is obvious that various modifications
of the controlling means as shown and described
could be made without departing from the spirit
50 of my invention.
What I claim as my invention is:
1. Temperature control mechanism compris
ing a thermostatically actuated arm mounted
to turn on an axis; a lever pivoted on the arm,
55 the pivot of the lever being oiTset relative to
the said axis; an adjustable regulator against
which the lever is moved by the arm to cause
it to rock relative to the arm; a switch arm
normally closing a circuit; and means for con
60 necting the lever, at a point substantially in
alinement with the said axis, and the switch
arm to move the latter to open the circuit when
the levei` is rocked on its pivot.
2. Temperature c_ontrol mechanism comprising
a thermostatically actuated arm mounted to turn
on an axis; circuit opening and closing means
including a switch arm normally closing a circuit;
lever pivoted intermediate its ends on the
70 thermostatically actuated arm; and an adjust
with the lever at a point in alinement with the _
said axis for actuating the switch arm to move
its contact out of engagement with the ñxed con
tact when the lever is rocked on its pivot.
'7. rI‘emperature control mechanism compris
ing a thermostatically actuated arm mounted to ,
turn on an axis; a lever pivoted on the arm, the "
pivot of the lever being offset relative to the said
axis; a pivoted abutment member adapted to
be engaged by the lever to cause it to rock rela
tive to the arm; means for engaging the abut- ,
ment member close to its pivot to limit the move
ment of the said member in one direction, the
means being adjustable to vary the movement of
the arm before the lever engages the abutment
member; a switch arm normally closing a cir
cuit; and means for connecting the lever, at a
point substantially in alinement with the said
axis, and the switch arm to move the latter to
open the circuit when the lever is rocked on its
pivot.
8. Temperature control mechanism comprising
a thermostatically actuated arm mounted to turn
on an axis, a lever pivoted intermediate its ends
on the arm, one of the said lever and arm parts
able regulator positioned for engagement by one
having a stop for engaging the other of said
parts to limitJ the rotary movement of the lever
end of the lever to cause it to rock relative to
the arm, the other end of the lever, at a point
the lever having a lug extending laterally there
substantially in alinement with the said axis,
75 being connected with the switch arm so that the
CII
in one direction relative to the arm, one end of
from; a switch arm normally closing a circuit;
and an adjustable regulator adapted to be en 75
2,135,858
gaged by the lug to cause the lever to be rocked
relative to the arm; the other end of the lever
at a point in alinement with the said axis being
connected with the switch arm so that the cir
cuit will be broken when the lever is rocked on
its pivot.
9. Temperature control mechanism comprising
3
pivoted on one arm of the U shaped frame, the
switch arm being pivoted intermediate its ends
on the other arm of the U shaped frame; a lever
pivoted on the first mentioned arm; connections
between the toggle member and a point on the
lever substantially in alinement with the said
axis; and an adjustable regulator adapted to be
thermostatically actuated means including an
engaged by the lever to cause it to rock relative
oscillatable arm; a lever pivoted on said arm; a
adapted to be engaged by the lever to cause it
to rock relative to the first mentioned arm; and
to the arm so that the toggle member will be
moved to cause the circuit to be opened, the back
stop being positioned relative to the ñxed con
tact to limit the movement of the switch arm so
that the toggle member Ácannot move over center.
means connected with the lever ot a point sub
15 stantially in alinement with the axis of the
ing a thermostatically actuated arm mounted to
10 switch arm; means tending to move the switch
arm to close a circuit; an adjustable regulator
1l. Temperature control mechanism compris
oscillatable arm for actuating the switch arm to
turn on an axis; an adjustable regulator; a mem
cause the circuit to be `opened when the lever
is rocked on its pivot.
ber carried by the arm and movable relative
10. Temperature control mechanism compris
20 ing a. thermostatically actuated arm mounted
to turn on an axis; circuit opening and closing
means including a movable switch arm provided
with a contact; a fixed contact; a back stop
spaced from the fixed contact; a U shaped spring
frame having two arms; a toggle member having
one end pivotally engaging an end of the switch
arm, the other end of the toggle member being
thereto, the said member being adapted to en
gage the regulator to cause a movement of the
member relative to the arm; a switch arm nor
mally closing a circuit; and means connected
with the member, at a point substantially in aline
ment with the said axis, for moving the switch
arm to open the circuit when the member is
moved relative to the arm to shift the said con- ,Y
nection out of alinement with the said axis.
ROBERT H. J. STARSMEARE.
Документ
Категория
Без категории
Просмотров
0
Размер файла
480 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа