HERMETICALLY CLOSED SWITCH ASSEMBLY TO BE USED WITH ONE AXIS
ROTATING VALVE
BACKGROUND OF THE INVENTION The present invention relates to switches of the type that can be placed on a rotating shaft, particularly the axis of the rotary valve, in which, when the user rotates the valve shaft to a desired position, it is activated or deactivates the switch to close or open a circuit. Such switches are used in valves used to regulate the flow to gaseous fuel burners in the upper part of the cooker, where the valve shaft is arranged to go through the switch and have a knob on its end to facilitate the user manual operation. In applications to gas burners, it is common for the circuit breaker to close a circuit to activate an electric spark ignition, when the valve shaft has been rotated to a predetermined gas valve opening position, allowing the fuel flow to the burner. In the applications of switches for gas burner valves, there were problems with the spillage of food and liquids in the upper part of the kitchen and its filtration inside the switch with contamination of the contacts and deterioration in the performance of the switch . This has been particularly troublesome when the ignition switch of the gas burner was housed above the axis of the individual burner valves fixed to the valve body with fixing means such that one side of the switch rested against the valve body and the remaining parts of the switch were exposed to the burner well on top of the stove. Therefore, it was desired to provide a way, or means, to protect against contamination the switch in its applications to the gas burner valve, particularly with liquid foods that could deteriorate the electrical contacts of the breaker that are within the switch box. It was also desired to provide a reliable switch for the gas burner valve, resistant to contamination and economical in large scale manufacturing to be applied in consumer appliances. It was also desired to provide a rotary switch, capable of being fixed on an axis, which is resistant to contamination and which can be connected with continuous connecting insulated wires. Summary of the Invention It is an object of the present invention to provide a hermetically sealed switch assembly for use with a rotating shaft and especially the shaft of a rotary valve. It is another object of the present invention to provide a hermetically sealed switch assembly for use with a rotating shaft and having a simple design and a relatively low manufacturing cost, and which provides reliable interruption when the shaft is rotated to a predetermined position. It is still another object of the present invention to provide a switch capable of being fixed on a rotary valve shaft, which will be resistant to contamination and which can be connected with continuous connecting insulated wires. The present invention utilizes an annular rotor capable of being mounted on an axle for a power transmission connection, such as a valve shaft, and rotating therewith, the rotor being articulated in a box housing a switch that can close or open a circuit in response to the rotation of the rotor to a certain position. The rotor has an annular flange extending radially outward thereof and carries an annular seal between the flange and the box to hermetically isolate the rotor from the box. The box houses a pair of terminal means spaced apart from each other which are capable of receiving, with electrical contact by displacement of the insulator, a pair of continuous connecting isolated wires passing through the switch housing. Electrical switch means are provided inside the box to effect, when the rotor rotates, the closure and the opening of an electrical circuit between the spaced terminal means. In one embodiment the switch means comprises a bar for shorting, arcuate, rotating with the rotor, to close and open the electrical contact between the spaced terminal means. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an exploded view of an embodiment of the invention using a rotary switch activated by a cam. Figure 2 is a cross section of the assembled switch of Figure 1. Figure 3 is a view similar to that of Figure 1 of an alternative embodiment of the invention using a shorting bar, and Figure 4 is a cross section of the embodiment of Figure 2 already assembled. Detailed Description With reference to Figures 1 and 2, the breaker assembly of the present invention is generally illustrated at 10 and includes a base, preferably in the form of an open box 12, and a cover 14 removably attached to the base in any manner suitable, such as by elastic tabs 16 that mesh with projections or tines 18 provided in the base. The base has a pair of spaced channels 20, 21, substantially parallel, for insulated connecting wires, which will be described later. A pair of electrical terminals 22, 24, preferably formed by a strip material, have wire receiving notches, identified with the reference numerals 26, 28 respectively. The terminal 22 is housed in a recess or slot 30 of the side channel 21. The terminal 22 has a blade arm portion for contacts 34, which forms an integral part thereof and extends therefrom. In the illustrated embodiment, the contact arm 36 has a fixed contact function, while the contact blade arm 34 has the function of a mobile contact blade, as will be described later. With the terminals 22, 24 housed in the grooves provided in the base 12, the individual insulated connecting wires 38, 40 are forced into the grooves 28 of each terminal, the edges of the grooves displacing or passing through the insulation of the wires establishing the electrical contact with the conductor that they carry inside, thus making it possible for the insulated connecting wires to pass through the box 12 of the switch 12 in the form of a continuous member, without the need to cut them or form joints. An annular rotor, indicated generally at 42, has a tub portion 44 and an annular flange 46 extending radially outward and having a spline 48 formed on one of the axial faces of the flange. The tub 44 is hinged to rotate in the annular groove 50 provided in the base 12, which is concentric with an opening or exhaust 52 passing through it, allowing the annular groove 54 a free access to the lower end of the tub 44. The periphery The interior of the tub 44 is provided with a pair of flat portions 54 arranged in opposition, capable of meshing with a flat surface (not shown) provided on the shaft of a rotary valve. The valve shaft is indicated in dotted lines in Fig. 1 and carries the reference number 58. Similarly, an exhaust or opening 56 is provided in the lid 14 to allow the valve shaft 58 to extend to through the rotor 42 and protrudes from the cover 14. A flexible seal, preferably in the form of an O-ring 60, is received in the groove 48 of the flange of the rotor and sealingly connects the flange to the lower surface of the cover 14 , to prevent the entry of foreign material into the box. The rotor vat 44 includes at least one cam lobe 62 provided in the rotor to effect, when rotated, a movement of the contact blade 34 to press against the contact 36. With reference to Figures 3 and 4, another embodiment of the invention is generally indicated with 100 and comprises a bottom box or base 102 having a pair of parallel and spaced channels 104, 106, formed therein, capable of accommodating insulated connecting wires in a manner similar to channels 20, 21 of the embodiment of Figure 1. A pair of contact terminals 108, 110 is disposed on opposite sides of a cavity. central 111 formed in the base, the terminals being housed in respective cutouts or grooves indicated with 112, 114 respectively, which extend transversely with respect to the slots 104, 106. Each of the terminals 108, 110 has a portion that is it extends through the wall of the channels opening into the cavity to form fixed electrical contacts indicated with reference numbers 116, 118 respectively. Each of the terminals 110, 112 has a slot indicated with 120 and 122 respectively, capable of receiving therein an insulated connection wire making contact with the conductor contained therein. It should be understood that in Figure 3 the isolated connection wires were omitted, but these are shown in Figure 4. An annular rotor, indicated generally at 124, has a trough 126 with an annular ridge extending radially outwardly from the same, as indicated by the reference number 128; it has an annular shoulder 130 that exactly matches an opposite inner joint diameter 132 provided in the base. The opposite inner diameter 132 and the shoulder 130 work as a labyrinth to trap foreign materials that were to enter the interior of the switch box through the lower end of the tub. A plurality of recesses 134, 136 spaced thereon are formed on the rotor shaft 126. The recesses 134, 136 mesh with tongues 138 spaced in correspondence on the inner periphery of the conductor 140 which is pressed into the tub 126 to fit against the lower surface or the lower axial face of the flange 128. The tongues 138 abruptly enter the slots 134, 136 to provide a resistance transmission between the tub 126 and the ring 140. The scraper ring 140 has a plurality of scraper contacts 142 extending from an axial phase thereof, substantially in a downward direction, looking at the Figure 3. The rotor 124 has a pair of flat surfaces 144 formed on its inner periphery, adapted for a transmission gear with a surface (not shown) formed on the axis of the valve 146 indicated with dashed lines in Figure 4. The enlarged diameter of the flange 128 of the rotor has an annular groove 148 formed on its axial surface opposite the conductive ring 140, housing the groove 148 an annular sealing gasket, preferably an O-ring, indicated by reference numeral 150. A cap member, which forms part of the switch assembly housing, is indicated 152 and has an aperture 154 formed therein into which it enters. the bowl of the rotor, the cover having formed inside it a surface of opposite inner diameter 156, whose surface is in watertight contact with the O-ring 150. The cover 152 carries detachable connecting means, which comprise, in the embodiment illustrated 100, tabs on its sides, indicated with reference numbers 158, engaging these tabs with the side portions of the base 102 for a quick releasable attachment of the cover 152 on the base 102. It will be understood that when the user rotates the shaft valve 146 also rotates the rotor 124 and the conductive ring 140, causing the scraping contacts 142 to short circuit the fixed contacts 116, 118 to complete a circuit. between the insulated connecting wires indicated by the reference numbers 160, 162 in Figure 4. Therefore, the present invention provides an original and novel switch assembly, adapted to be placed on a rotating shaft, especially the shaft of valve, the switch having an annular rotor with which the surfaces of the shaft mesh and rotate it. When the rotor of the switch is rotated, the contacts that are in the switch box are closed and open, which has a pair of insulated continuous connection wires fixed inside with the insulation displaced to allow electrical contact with the conductor. in the isolated wires, secured by a quick-closing lid on the box. An annular sealing gasket on the rotor joins the rotor hermetically with the lower surface of the cover and protects the contacts that are in the switch against contamination with foreign materials. Therefore the switch is ideal to be used in combination with the valve shaft of a gas burner to regulate the ignition spark circuit, the user turning the valve shaft to a position that allows fuel to flow to the burner . Although the present invention has been described herein in relation to the illustrated embodiments, it will be understood that those of ordinary skill in the art will be able to modify and vary the invention, which is limited only by the following claims.