US2333261A

US2333261A - Safety switch and pilot valve

Info

Publication number: US2333261A
Application number: US436459A
Authority: US
Inventors: Harold A Mantz
Original assignee: Milwaukee Gas Specialty Co
Current assignee: Milwaukee Gas Specialty Co
Priority date: 1942-03-27
Filing date: 1942-03-27
Publication date: 1943-11-02
Anticipated expiration: 1960-11-02

Description

Nov. 2, 1943. H. A. MANTZ SAFETY SWITCH AND PILOT VALVE 2 Sheets-Sheet l Filed March 27, 1942 J TOM 2 Nov. 2, 1943. -r

SAFETY swrrcn AND PILOT VALVE Filed March 27, 1942 2 Sheets-Sheet 2 0 i J I m; m a 0 J J. H m .N E W 0 M db 6 m 2 h 0 J w 3 I m i w 5 0% Z .J V i [4H1 J j 54 ll 5 D0 3 M u M Q.. w 0 EZV 0 m o 5 w 9 v v w 5% Patented Nov. 2, 1943 UNITED STATES PATENT OFFICE SAFETY SWITCH AND PILOT VALVE .Harold A. Mantz, Milwaukee, Wis., assignor to Milwaukee Gas Specialty Company, Milwaukee. Wis., a corporation of Wisconsin Application March 27, 1942, Serial No. 436,459

11 Claims. (Cl. 200-53) The present invention relates to protective dein a device of the character described, simple and vices for burner apparatus comprising a main improved means for indicating the position of burner and a secondary or pilot burner, and more the first mentioned switch or controlling member.

particularly to a combined safety switch and sec- While the particular structural features and ondary or pilot valve operativ responsive to con- 5 combinations by which I obtain a device of the dition responsive means-for example, upon excharacter'set forth are important features withtinguishment of a pilot light-4o shut off the supin the more specific aspects of the invention, ply of fuel for the main burner and for the pilot it is to be understood that the precise features burner. shown and described may b varied within the The present application is concerned more spel broader aspects of the invention. cificallywith an improvement in safety switches In order to acquaint those skilled in the art of the type disclosed in the copending application with the manner of constructing and operating of Clarence Wantz, Serial No. 395,956, filed May a device in accordance with my invention, I will 31,1941. describe in connection with the accompanying One of the main objects of the present invendrawings one preferred embodiment of the inven tion is .to provide in a device of the class detion.

scribed, wherein a switch or other controlling In the drawings:

member is maintained in operating position as Figure 1 is a sectional view of a device cmlong as an electromagnet connected in circuit with bodying the present invention, showing the switch a thermoelectric generator is energized by the in'open position and the means for permitting heat of a flame on the thermoelectric generator fl w o fluid o t pilot burner in closed D and operates to safety position upon extinguishsition; ment of the flame, the combination with such de- Figure 2 is a more or less diagrammatic view vice of a secondary or pilot valve or controlling showing the device in connection with burner member under the control of the reset means for apparatus; resetting the armature constituting a part of the Figure 3 is a sectional view taken substantially device to attracted position and the first menonline 3-3 of Figure 1; tioned switch or controlling member to operat- Figure 4 is a fragmentary detail section taken ing position. on line 4-4 of Figure 1;

Another and more specific object of the in- Fi u e 5 is a fr me ry e il vi w sh win vention isto provide a secondary valve or conthe position of the switch actuator reset means trolling member having an open position and a with the switch in ope position and the reset closed position and actuated from one of said member and reset stem in reset position; positions to the other position by the resetting Figure 6 is a view similar to Figure 5 showing movement of the reset means. the position of the reset member in its projected Another more specific object of the invention position with the switch in closed position and is to provide a secondary valve or controlling with the reset stem retained in its reset position; member which is actuated from closed or safety d position to open or operating position by the re- Figure '7 is an elevational view illustrating a setting movement of the reset means and before 40 modified form of the invention. the first mentioned switch or controlling member In Figure 2 of the drawings, a gas or other fuel is operable to closed or operating position. burner of any suitable 0! preferred type is con- Another more specific object of the invention ventionally illustrated at Ill. The burner It! may is to arrange the combinationset forth in a manbe the burner of a room or space heater, water ner to use the first mentioned switch for conh er, floor furn e, gas e, or any other trolling the main shutoff valve for the main burnburner. A gas or other fuel supply pipe I l leads er and the secondary valve as a pilot valve for to the burner ill for the delivery of gas or other controllingthe supply of fuel to a pilot burner fuel theretofor example, throu h a mixin for lighting the main burner. chamber (not shown) to which air is admitted in Another object of the invention is to provide the usual way, as well understood in the art. a switch of a character described which is a sim- A power actuated or electroresponsive valve I2, ple, inexpensive, and improved construction emsuch as a solenoid or motor valve, is interposed in bodying few parts and operative effectively to the fuel supply pipe H. The valve I2 is shown accomplish the purposes set forth. as comprising a valve body l3 and a hood l4 hav- Another object of the invention is to provide, ing suitable power operated valve actuating means therein. A step-down transformer l5 supplies power for the operation of the valve l2. This transformer comprises a line voltage primary I6 and a low'voltage secondary H. The primary I6 is connected to line wires l8 leading to any suitable source of current or power (not shown). The valve actuating means for the valve I2 is connected into the secondary circuit l8. The control switch of the present invention is also connected into the secondary circuit l9, as will presently appear.

'For' purposes of illustration, it may be assumed that the valve I2 is of a character to be actuated to open position by closing of the circuit l9, and to be held in open position to supply fuel or operativeenergy to'the burner as long as the circ uit I9 is closed. The valve l2 may have spring means, or other suitable means, for actuating the valve to closed position to shut off the supply of'iuel to the burner when the circuit I8 is opened or otherwise disabled.

The control switch is shown as located within a housing 28. The opposite ends of the back wall of the housing are turned in to form end walls 2|, andat the opposite sides. of the back wall are inturned flanges 22. The cover 23 is of generally U- shaped cross section and tits over the inturned end walls 2| with the inner marginal edges oi the sides of the cover fitting over the flanges 22. Slots 24 opening inwardly from the inner marginal edges of the side walls of the cover fit over the shanks of screws 25 which are adapted to be tightened to secure the cover in place on the base of the housing and to be loosened to permit removal of the cover.

The front wall of the cover 23 has an opening 28 through which an indicator is adapted to be viewed to indicate the position of the switch, as will hereinafter appear.

An actuator or reset member 30 operates between open and closed positions by rectilinear movement through an opening 3| in the adjacent end wall 2| of the housing. The outer end of the actuator member 38 is provided with an operating button 32. The inner end of the actuator or reset member 30 is turned toward the back wall of the housing, and at the back wall of the housing the actuator member is turned at substantially right angles at 34 for sliding movement on the back wall of the housing. A rivet 35 retains the adjacent angular end 34 of the actuator member on the back wall of the housing, and the shank of the rivet 35 passes through an elongatedslot 36 in the angular end 34 of the actuator member to permit the rectilinear sliding movement of this member.

The actuator member 38 is yieldingly retained in its outwardly projected position as shown in Figures 1 and 5,'and, upon release of the button 32, as will presently appear, is returned to this outwardly projected position by a coiled spring 38 connected between the rearwardly turned intermediate portion of the actuator member and a spring anchoring lug 39 pressed inwardly from the adjacent end wall 2| of the housing. The screws 25 and slots 24 may be positioned at different distances from the opposite'ends of the device to assure proper mounting of the cover 23. Pivoted at 40 on the actuator or reset member 38 is a lever 42.

The means for holding the switch closed is shown in the form of an electromagnet located within the housing 28. The electromagnet selected for illustration comprises a magnet frame 45 secured, for example, to a terminal bushing 46. The coil 41 of the electromagnet is wound around the legs of the magnet frame 45. The bushing 46 is shown as splayed at 48 to prevent its turning in the opening 48 in the adjacent end wall 2i. The bushing 46 is also externally threaded for threaded engagement at 50 with a nut 52 by means of which the bushing is clamped in place in the end wall 2| of the switch housing, the externally threaded and tubular shank of the bushing extending from the head at the inner end of the bushing out through the opening 48 for this purpose.

The electromagnet has an armature 55 attached at 56 to the adjacent end of a stem 51, if desired, in a manner to permit self-accommodation of the armature, when in attracted position, to the pole ends of the magnet frame 45. The electromagnet and armature are enclosed within a cup 58. The stem 51 extends for reciprocatory movement through an opening 58 in the inner end of the cup 58. The opening 59 is sealed by suitable sealing material, such as a leather washer, felt packing or the like, as indicated at 60, interposed between the inner end of the cup 58 and a spring seating disc 62.

The end of the stem 51 opposite the end on which the armature 55 is mounted is secured by a pin 64 to the adjacent end of a reset stem 65. The opposite end of the reset stem 65 is pivoted, for example, by a screw 86 to one arm of the lever 42 on one side of its pivotal attachment at 40 to the actuator member 30. The reset stem 65 is of square or polygonal section, with a rounded or cylindrical end fitting into a valve spring seat member 68. A coiled spring 10, interposed between the spring seat member 68 and the spring seating disc 62, actuates the armature 55 to retracted position and the reset stem 65 and pivoted lever 42 to the position shown in Figure 1 when the electromagnet is deenergized, for example, upon extinguishment of the flame to which the device is responsive.

The particular switch shown in the drawings comprises a switch base 15 in the form of a block of suitable insulating material closed at the front and hollowed out from the back to form the switch cavity 16. A switch bracket 18 in the form of a cup having its back wall spotwelded or otherwise suitably secured to the back wall of the housing 20 has three outstanding side flanges I9, 88, and 8|, the fourth side being closed by the adjacent side flange 22 of the housing 20. The switch base 15 fits removably in the bracket 18 with its open back side presented to the back wall of the housing 28, and has along one side a ridge or ledge 82 which is engaged by the inturned outer edge of the flange 80. The opposite side of the switch base 15 has a corresponding ridge or ledge 83, and a cotter pin 84 is passed through openings 85 in the flanges 19 and 8| and engages the ridge or ledge 83 firmly and removably to secure the switch base 15 in place on the back wall of the housing 20. One shank of the cotter pin 84 is spread or turned inwardly at 86 to prevent accidental displacement of the pin.

Positioned in spaced relation within the switch cavity 16 are a pair of contact pins 90 secured to separate spaced terminal members 9|. which terminal members pass through and are secured in the front .wall 92 of the insulating switch base 15. Each terminal member has an integral inwardly spaced terminal portion 93 also secured in the front wall 92 of the switch base 15. The conductors l9 of the circuit for the valve l2,

which are insulated at 94, enter the housing 20 through an insulating grommet 95. One of the conductors I is connected by a terminal screw 96 to the terminal member SI for one contact 90, and the other conductor I9 is connected by a corresponding terminal screw to the corresponding terminal member 9| for the other contact 90. A switch insulator piece 91 is preferably interposed between the open back of the switch base I and the base of the bracket I8.

The switch stem I00 has rectilinear sliding movement in the switch base I5 with the headed outer end of the stem operating in position for cooperation with the inturned end I02 of an arm I03 on the switch lever 42, this arm I03 being on the side of the pivot 40 opposite the side of the lever which is pivoted to the reset stem 65. Within the switch cavity 16 the reduced inner end of the stem I00 passes through a bridging contact plate I05. A coiled spring I06, surrounding the reduced inner end of the stem I00 and interposed between the contact plate I05 and a shoulder I0I on the switch base I5, yieldingly urges the plate I05 into bridging contact with the contacts 90 to complete the circuit I9. By engagement of the contact plate I05 with the shoulder I08 on the stem I00, the spring I06 also yieldingly urges the stem I00 to its out wardly projected position as shown in Figure 1.

The pivoted arm 42 has a flag or indicator member I I0 formed integral therewith. This indicator member IIO has "on and off" markings thereon as shown, or is provided with colored or other appropriately marked portions for indicating through the opening 26 in the switch cover 23, the position of the switch, as will presently appear.

The pilot burner I I5, which is located in juxtaposition to the main burner I0 to maintain a pilot light for lighting the main burner, is supplied with gaseous fuel by a pilot supply pipe II 6. The pilot supply pipe I I6 is connected to the outlet I40 of a pilot or secondary valve I4I. A conduit I4'2 extends from. the inlet I43 of valve MI and is connected to fuel supply pipe II anterior the electromagnetic valve I2.

A thermocouple, indicated at H8, is placed in position so that the hot junction I I9 thereof will be heated by the pilot flame as long as the pilot flame is burning. The construction of the thermocouple may be similar to that more fully disclosed in Oscar J. Leins Patent No. 2,126,564, granted August 9, 1938, where a thermopile or any other form of thermoelectric generator may be employed.

For the purpose of the present description, sufiice it to state that the particular thermocouple II8 selected for illustration comprises an outer tubular metallic thermocouple member I and an inner metallic thermocouple member I2I of difierent thermoelectric characteristics. The inner thermocouple member I2I is joined at one end to the outer end of the outer thermocouple member I20 to form the thermojunction II9 which is placed in position to be heated by the pilot light. An inner lead conductor I22 is joined tothe inner thermocouple element I 2| to form an internal thermojunction I23, and an outer tubular lead conductor I24 is connected to the outer thermocouple member I20, for instance through a sleeve I25, to form a third thermojunction I26. The inner lead conductor I22 is insulated from the outer lead conductor I24, for instance, by a wrapping of insulation on the inner lead conductor as indicated at I23.

A quick detachable or removable connection is preferably provided between the opposite ends of the leads I22 and I24 and the coil 41 of the electromagnet. The inner lead I 22 has a connector cone I30 which seats in the correspondingly recessed outer end of the terminal tip I32 and is clamped in contact therewith by a connector sleeve I34. The adjacent end of the Outer tubular lead conductor I24 is connected in circuit with one side of the coil 41 through the bushing 46, and the other side of the coil is connected to the terminal tip I32, the parts being suitably insulated as shown.

The valve MI is disposed laterally of the right hand side wall of the housing 20 as viewed in Figures 1 and 2, and is provided with a flanged member I44 which is adapted to be secured to the back wall of the housing. The valve housing I4I comprises a bore I45 and a counterbore I46 extending inwardly of the bore I45 and providing a valve seat for a ball valve I41. The ball valve I4! is normally urged against its seat, to close the end of the bore I45, by a coil spring I48, one end of which bears against the ball and the other end is adapted to be disposed in a recess I49 in a cap member I50. A plunger I5I, having a plunger cap I52, is mounted for sliding movement in an end member I53 fitting in a suitable bore provided therefor in the end of valve housing opposite the cap end I50. The marginal edge of a flexible diaphragm I64 is secured between the cap member I53 and the valve housing to prevent escape of gas at this end of the housing.

The outer end of plunger member I52 is provided with a hemispherical head I 55 which is adapted to be engaged by the flat surface of a flat spring member I58. The reset stem 65 is provided with a substantially V-shaped notch, and one end of the spring I58 is formed conformably to fit in the notch of the reset stem 65. The other end of spring member I58 is turned at right angles and is suitably secured to the upper end of the housing 20. It will be seen that as the reset member is moved downwardly, the inclined surface I60 of the reset arm 65 will bias the spring member I58 outwardly to engage the rounded end I55 of the plunger head I52 moving the plunger rod I5I inwardly which will unseat the ball valve I41 and connect the inlet and outlet I43 and I40 respectively through the bores I45 andcounterbore I46 to supply fuel to the pilot burner I I5. With the armature 55 in its retracted position and the reset or actuator member released, the spring I48 will seat the ball valve In on its seat and shut oil flow of fuel through the valve I4I.

In Figure 7 I have shown a modified form of pilot control valve I60 which comprises a valve housing I6I suitably secured to the back Wall of the housing of the device. The housing is in the form of an elbow having an inlet I62 and an outlet I63 the axes of which are disposed substantially at right angles to each other and lie substantially in the same vertical plane. A suitable spring loaded ball valve, which may be of any known type, is disposed in the housing and is adapted to be raised oil" its seat by a plunger I64 one end of which is disposed in an arcuate groove I65 of the reset stem 65' upon downward movement of the latter to establish communication between the inlet and outlet of the valve. The remainder of the device shown in Figure 7 is the same as that of the embodiment above described and the like reference numerals indicate the same parts. The last described form of valve housing is desirable for use in situations where it is more convenient to dispose the inlet and outlet connection for the pilot light at right angles to each other rather than having the axes of the inlet and outlet arranged in parallel relation as in the embodiment first described.

identical.

To start the operation of the system shown in the drawings, the following sequence is followed:

The actuator or reset member 30 is pressed inwardly from the position shown in Figure 5 by engaging the button 32 with the hand or fingers and imparting pressure thereto. The spring I at this time, and when the actuator member 30 is in projected position as shown in Figure 5, tends to rock the lever 42 about its pivot 40, holding the inturned end I02 of the lever against the switch pin I00, and the spring I0, being stronger than the spring I06, holds the switch pin in its inwardly retracted position and the bridging contact I05 out of contact with the contacts 90. As the actuator or reset arm 30 is pressed inwardly, the spring I0 continues to hold the switch plate I05 in open position, and the inward movement of the actuator arm 30 rocks the lever 42 about the cooperating end of the switch pin I00 as a fulcrum until the armature 55 is cooked or set into attracted position against the pole ends of the magnet frame 45.

With the parts in this position it will appear from the above description of the valve I4I that the ball valve M1 is held off its seat against the action of the spring I48 and gas will flow through the pilot burner II5. Upon ignition of the burner the pilot flame of the thermoelectric generator will energize the electromagnet sufficiently so that it will hold the armature 55 attracted thereto.

When the electromagnet is energized sufficiently to hold the armature 55 in attracted position, the actuator member 30 is released and the reset stem 65 remains in cocked position holding the pivot 66 in fixed position so that the outward movement of the actuator member 30, through its connection at 40 with the arm 42, swings this arm in a clockwise direction about the pivot 66 and under the action of the spring 38 to the position shown in Figure 6. The switch pin I00 is released upon separation of the cooperating portion I02 of the arm 42 therefrom, and the spring I06 moves the contact plate I05 into bridging contact with the contacts 90 to close the circuit I9. The circuit is thus closed not by the inward movement of the reset member 30, but by the movement of this reset member 30 to its outwardly projected position following the resetting operation and only when the electromagnet is effective to hold the armature 55 in attracted position.

If the pilot burner is not lighted to produce the thermo-electric current for holding the armature 55 in attracted position upon setting the same to that position by the actuator member 30, the armature 55 and the stem 65 will move to retracted position with the movement of the actuator member 30 toits outwardly projected position, the spring I0 at such time maintaining the switch plate I05 in open position through the pivoted arm 42.

Also, if sufhcient current has not been generated to hold the armature 55 in attracted position, the plunger comprising the plunger cap I52 and the plunger rod I5I will return to the position In all other respects the devices are shown in Figure 1 under the action of the spring I48 to close or shut off the flow of fuel through the pilot light I I5.

If, after the parts are set; as shown in Figure 6 and the pilot burner is lighted to hold the parts in the positions shown in this figure, the pilot burner is extinguished, the armature is released, and the flow of fuel to the pilot burner H5 is shut off. The spring I9 then operates to move the armature to retracted position and, through the reset stem 65, swings the pivoted arm 42 in a counterclockwise direction about its pivot 40 on the actuator member 30, causing the inturned end I02 of the arm 42 to engage the switch pin I00, forcing the same inwardly and separating the switch plate I05 from the contacts 90 to open the switch. This opens or interrupts the circuit I9 and the valve I2 operates to closed position to shut off the supply of fuel to the main burner.

When the armature is in retracted position and the switch is in open position as shown in Figure 5, the off marking on the indicator arm H0 is positioned to be viewed through the opening 26 to indicate that the switch is off. When the armature is in attracted position and the actuator member 30 is in its outwardly projected position, the on marking on the indicator arm IIO is positioned to be viewed through the opening 26 to indicate that the switch is on."

The front wall of the insulating switch base I5 may'be provided with an integral insulating rib I forming an insulating barrier between the terminals 9|. It may also have integral insulating side ribs IBI forming insulating barriers at opposite sides thereof.

The embodiment of the invention shown in the drawings is for illustrative purposes only, and it is to be expressly understood that said drawings and the accompanying specification are not to be construed as a definition of the limits or scope of the invention, reference being had to the appended claims for that purpose.

I claim:

1. In a switch of the class described, in combination, a reset member, a lever having pivotal connection intermediate its ends with said reset member, a switch having a switch stem cooperable with one end of said lever and constituting a fulcrum about which said lever is adapted to be rocked by resetting movement of said reset member, a reset stem pivotally connected to the other end of said lever and adapted to be reset by the rocking movement imparted to said lever by resetting movement of said reset member, a valve disposed laterally of said reset stem, means associated with said reset stem and said valve for opening said valve upon resetting movement of said reset stem, said reset stem in its reset position holding said valve in open position, and means for holding said reset stem in reset position.

2. In a device of the character described, the combination of a reset member, a lever having pivotal connection intermediate its ends with said reset member, a switch adapted to be actuated to open position upon resetting movement of said reset member, said switch having a switch stem cooperable with one end of said lever and constituting a fulcrum for said lever in the open position of said switch, a reset stem pivotally connected to the other end of said lever and adapted to be actuated by the rocking movement imparted to said lever by resetting movement of said reset member, a valve disposed laterally of said reset stem. means associated with said reset stem and said valve for opening said valve upon resetting movement of said reset member, said reset stem in the reset position of said reset member holding said valve open, means for holding said reset stem in reset position, and means for closing said switch upon release of said reset member when said reset stem is held in its reset position.

3. In a device 01' the character described, the combination of a reset member, a lever having pivotal connection intermediate its ends with said reset member, a switch adapted to be actuated to open position upon resetting movement of said reset member, said switch having a switch stem cooperable with one end of said lever and constituting a fulcrum for said lever in the open position of said switch, a reset stem pivotally connected to the other end of said lever and adapted to be actuated by the rocking movement imparted to said lever by resetting movement of said reset member, a valve having a plunger for opening the same, said reset stem in the reset position of said reset member engaging said plunger and holding said valve open, means for holding said reset stem in reset position, means for closing said switch upon release of said reset member when said reset stem is held in its reset position, and means'i'or returning said reset member to its normal position.

4. In a device of the class described, a reset member adapted to be actuated between resetting and projected positions by rectilinear movement, a lever pivotally connected intermediate its ends to said resetmember for rocking movement upon actuation of said reset member, a switch, a switch stem adapted to be engaged by one end of said lever and movable rectilinearly thereby to open said switch, said switch stem constituting a fulcrum for said lever in the open position of said switch, a reset stem pivotally connected to the other end of said lever and movable rectilinearly thereby, a valve disposed laterally of said reset stem, means associated with said valve and reset stem for opening said valve upon resetting movement of said reset member and holding said valve open when said reset stem is disposed in its reset position, means for holding said reset stem in reset position, and means for closing said switch when said reset stem is held in reset position and said reset member is actuated to its projected position.

5. In a device of the class described, a reset member adapted to be actuated between resetting and projected positions by rectilinear movement, a lever pivotally connected intermediate its ends to said reset member for rocking movement upon actuation of said reset member, a switch, a switch stem adapted to be engaged by one end of said lever and movable rectilinearly thereby to open said switch, a reset stem pivotally connected to the other end of said lever and movable rectilinearly thereby, a valve, said switch stem constituting a fulcrum for said lever in the open position of said switch, a plunger for said valve, said plunger being actuatable rectilinearly by said reset stem to open said valve upon resetting movement of said reset member and holding said valve open when said reset stem is disposed in its reset position, means for holding said reset stem in reset position, and means for closing said switch when said reset stem is held in reset position and said reset member is actuated to its projected position.

6. The combination of claim 4 characterized by the provision of a flag member associated with the lever for indicating the open and closed positions of said switch.

7. The combination of claim 5 characterized by the provision of a flag member associated with the lever for indicating the open and closed positions of said switch.

8. In a switch of the class described, in combination, a reset member, a lever having pivotal connection intermediate its ends with said reset member, a control means having a controlling member cooperable with one end of said lever and constituting a fulcrum about which said lever is adapted to be rocked by resetting movement of said reset member, a reset stem connected to the other end of said lever and adapted to be reset by the rocking movement imparted to said lever by resetting movement of said reset member, a valve disposed laterally of said reset stem, means for opening said valve upon resetting movement of said reset stem, said reset stem in its reset position holding said valvein open position, and means for holding said reset stem in reset position.

9. In a switch of the class described, in combination, a reset member, a lever having pivotal connection intermediate its ends with said reset member, a control means having a controlling member cooperable with one end of said lever and constituting a fulcrum about which said lever is adapted to be rocked by resetting movement of said reset member, a reset stem connected to the other end of said lever and adapted to be reset by the rocking movement imparted to said lever by resetting movement of said reset; member, a second control means disposed laterally of said reset stem and having a controlling member actuated to operative position upon resetting movement of said reset stem, said reset stem in its reset position holding said last controlling member in its operative position, and means for holding said reset stem in reset position.

10. In a switch of the class described, in combination, a, reset member, a lever having pivotal connection intermediate its ends with said reset member, a. switch having a switch stem cooperable with one end of said lever and constituting a fulcrum about which said lever is adapted to be rocked by resetting movement of said reset member, a reset stem connected to the other end of said lever and adapted to be reset by the rocking movement imparted to said lever by resetting movement of said reset member, a control means disposed laterally f said reset stem and having a controlling member actuated to operative position upon resetting movement of said reset stem, said reset stem in its reset, position holding said controlling member in its operative position, and means for holding said reset stem in reset position.

11. In a device of the character described, the combination of a reset member, a lever having pivotal connection with said reset member, control means having a controlling member cooperable with said lever and constituting a fulcrum about which said lever is adapted to be rocked by resetting movement of said reset member, a reset stem connected to said lever and adapted to be reset by the rocking movement imparted to said lever by resetting movement of said reset member, a second control means having a plunger for actuating the same, said reset stem in the reset position or said reset member engaging said plunger to actuate the latter, and means for holding said reset stem in reset position.

HAROLD A. MANIZ.