JPS5912929B2 - gas ignition switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to electrical switches, and more particularly to electrical switches used to operate gas reignite circuits in gas ranges.

In accordance with the invention, the electrical switch has a plastic molded housing consisting of two identically molded sections of reduced thickness, which are screwed or screwed onto abutting surfaces from which a conventional gas tap spindle extends. otherwise arranged to be locked, the housing having a through opening extending therethrough, with a contact actuated cam positioned in the opening so that the spindle passes through the cam; A switch contact member, adapted to rotate with the spindle and preferably in the form of a strip, is held lockingly within the switch housing by interaction of the housing parts and is actuated by the cam in response to rotation of the spindle. It is located so that

...Using two identically shaped members for the housing and making these members thinner contributes to low cost, miniaturization, and ease of installation into a normal gas tap assembly. There is.

Furthermore, the switch contact part is held securely in place by the housing part, so that even lower costs can be realized.

The strip contact member is formed from a crab strip having two sections of different thickness such that the thinner flexible member is used as the contact section while the thicker section is used as the tough terminal section.

In order to achieve good electrical insulation of the switch contact member - the housing can be provided with two rectangular apertures,
An insulating shroud of the connector is received therein, and the shroud is configured within the housing to receive the terminal end of the contact member within the socket member.

The present invention will be explained in more detail below with reference to the drawings.

The switches illustrated in Figures 1 to 5 are intended for use in gas ranges and are secured to the gas tap assembly (only a portion of which is shown in the figures) by screws. and a gas tap control spindle extending through the switch housing.

As can be seen from Figure 1, the switch consists of two identical
It has a plastic molded housing comprising housing parts 1 and 2.

This housing is molded with an opening 3 extending through the housing, the opening 3 having a peripheral cam surface 5 and a locking device 6 in the form of a segment 6. The segment portion 6 that houses the rotatable cam 4 is capable of cooperating with a gas valve 23 or a flat portion of a “D”-shaped gas tap spindle 21 so that the cam 4 can be rotated on the spindle. (locking device).

The cam surface 5 responsive to rotation of the tap spindle actuates a contact member 8 which makes electrical contact with the other contact member 7 .

Contact members 7 and 8 are machined from strips of metal, such as beryllium copper or phosphor bronze, with thin flexible portions defining contact portions 9 and 10 and relatively thick rigid portions providing terminal portions 11 and 12. It has a part.

Terminal parts 11 and 12 are slots 1 of molding/bousing
3 and 14.

The contact part 10 extends below the molded stud 15, while the contact part 9 extends above the molded stud 16 of the housing part.

Contact members 7 and 8 are retained in slots 13 and 14 by spaced apart projections 24 on terminal portion 12 and projections 25 on terminal portion 11.

The cam 4 is rotatable by approximately 180 degrees of rotation.

This is achieved by the use of a stop member 2T of the block 29 formed integrally on the housing parts 1 and 2 and a fin-like segment 5b acting as an extension of the cam surface 5.

Segment 5b is substantially narrower than camming surface 5 and is preferably positioned centrally on surface 5 as shown in FIG.

When the cam 4 is in the position shown in FIG. 2 with the segment 5b passing in front of the stop member 27, the surface 5 of the cam
c contacts the stop member 270 surface 33.

As long as the cam 4 is in the position shown in FIG. 2 and the extended segment 5b of the cam 4 is in the vicinity of the stop member 27, the cam surface 5 will not come into contact with the contact member 8, so that the contact members 7 and 8 will remain open.

When the cam 4 is rotated further and the segment 5b is rotated far enough away from the stop member 27 that the end 31 of the segment 5b leaves the surface 33 of the stop member 27, the cam surface 5 comes into contact with the contact member 8. The contact member 8 is then pushed upward to bring it into contact with the contact member 7 as shown in FIG.

The circuit is thus closed until the end 5a of the cam 4 engages the surface 37 of the stop member 27.

The switch will remain closed when the cam 4 is rotated in the opposite direction until the end 31 of the segment 5b is again near the face 33 of the stop member 27.

When the end 31 of the segment 5b is again in the vicinity of the surface 33 of the stop member 27, the cam surface 5 no longer touches the contact member 8.
The circuit between the contact members 7 and 8 is opened, allowing it to spring back into its normal position.

Continued rotation of the cam 4 in the opposite direction is limited by the engagement of the surface 33 of the stop member 27 with the surface 5c of the cam 4, as described above.

- The housing parts 1 and 2 have posts 39 and 40 and 41 formed integrally in the housing parts 1 and 2 by means of corresponding openings 42 in the other housing part.
, 43 and 44 to fit and position.

Apertures 43, 44 are preferably blind holes, while aperture 42
extends through housing parts 1 and 2.

to provide electrical connection to the switch contact members;
The two connectors together with insulating shrouds 17a, 17b are pushed into openings 18 and 19, respectively, in the bottom of the switch housing so that the bottom ends of terminal portions 11 and 12 engage the socket members of the connectors.

The switch according to the invention has a very simple structure,
Molded plastic made from two identical parts.
It will be understood from the above description that there is provided a housing and a contact made of similarly processed strip metal.

Furthermore, the overall small thickness of the Uzing is
To enable a switch to be easily installed on the rear abutment surface of a normal front control panel of a gas range.

In an alternative construction of the switch, the cam may be provided with an axially extending peg, the peg having an opening in the gas tap knob instead of the cam having a segment for cooperating with the flat part of the spindle. be locked down.

Furthermore, the two housing parts may have flanges where the molded parts come together to prevent significant ingress of water.

FIG. 6 shows a circuit for relighting the gas burner of a gas range in the absence of a flame.

In this arrangement, an alternating voltage is supplied to the primary side of the transformer TI, and its secondary output is passed through the diode DI to the capacitor C.
1 is charged, and when one of the switches S1, in this example of the form shown in FIG. 1 and mounted on the spindle of each gas tap associated with a respective gas burner, is activated, through each capacitor C
The circuit for charging R 2 has been completed, and thus R
The voltage at the junction of T2 and capacitor C2 increases, but the increased voltage depends on the resistance of the associated secondary winding circuit of transformer T2 connected thereto.

The resistance of this second winding circuit depends on whether the burner associated with this circuit is lit or not, since this circuit has a spark gap in the flame path.

When the burner is ignited, the resistance of this circuit is relatively low (therefore the voltage at the junction of resistor R2 and capacitor C2 and also across the neon v1 which is the incorporation is insufficient and the neon breaks down). down) is not done.

(Then, the first caustic line of transformer T2 is Cyrisk-8CR1.
is not pulsed in response to conduction.

If the flame goes out in the gas burner, the resistance of the secondary winding of the associated transformer T2 will be relatively high so that the voltage across the neon v1 will be high enough to destroy the neon and thus cause the thyristor 5CR1 to Triggered by voltage applied through neon.

Upon triggering of 5CR1, the primary of transformer T2 in parallel with diode D2 and the associated secondary circuit are pulsed, thus creating a spark in the spark gap and, in the usual manner, extinguishing the extinguished flame. Reignite.

As soon as a re-ignition is carried out, the voltage across neon v1 decreases again due to the decrease in the resistance of the second circuit (and the trigger voltage is removed from the thyristor SCR, terminating the ignition pulse of the second circuit).

As is clear from the description with respect to FIGS. 1 and 6, when the gas tap is activated, the contacts of switch S0 close;
Once these contacts are made, they form a relight circuit if the flame is extinguished.

Although make contacts are shown in FIG. 1, it should be understood that break contacts can be used as an alternative in other circuit configurations and switch structures.

[Brief explanation of the drawing]

FIG. 1 shows an exploded view of an electrical switch according to the invention. 2-4 are front views of the switch of FIG. 1 with one housing section removed, showing various positions of the actuating cam. FIG. 5 is a cross-sectional view of the switch of FIG. 2 taken along line 5--5 of FIG. FIG. 6 is a circuit diagram of a gas reignition system for a gas range including multiple switches according to FIG. 1.2...Using part, 4...
Rotatable cam, 6...Segment part, 7, 8...
... Contact member, 15, 16 ... Stud, 27 ... Stop member, 17aL17b.
...Insulation shroud.

Claims (1)

Claims: 1. A switch for selective ignition of gas from a cast valve having a rotatable gas tap spindle, wherein first and second housing members lockable together are attached to the housing members. a rotatable cam having a central opening for receiving the gas tap spindle and having a cam surface; a central opening of the rotatable cam for receiving the gas tap spindle; a locking device for locking to the tag spindle and a segment narrower than the cam surface, the first and second L-shaped contact members each having a terminal portion and a contact portion; The contact portion of one of the contact members is positioned over the contact portion of the other contact member and both of the contact members are positioned over the cam so that the cam surface and the segment and a stop member is provided on one of the housing members to control the position of the lower contact portion with respect to the upper contact portion and to limit rotation of the cam, the stop n-1,lp material being in contact with the contact member. While disengaged, the cam surface has a width such that the segment rotates past the stop member for a limited portion of rotation of the cam, and the cam surface A switch for selective ignition of gas, characterized in that the switch is of a length such that the cam is engaged between extreme positions of rotation for a substantial remainder of the rotation of the cam. 2 the first and second housing members are configured to define first and second openings from which each of the terminal portions of the first and second contact members protrudes; 2. A switch for selective ignition of gas as claimed in claim 1, characterized in that an insulated socket is respectively positioned in one of said openings and receives one of said terminal parts. 3. one of the housing members has first and second slots, and one of the housing members has first and second slots in place within the housing;
The switch for selective ignition of gas according to claim 1, wherein the switch holds the terminal portion of the contact member. 4 first and second studs are molded into the housing such that one stud is above one of the contact portions and the other stud is below the other of the contact portions; A switch for selective ignition of gas according to claim 1, characterized in that: 5. The switch for selective ignition of gas according to claim 1, wherein the terminal portion of the contact member is relatively thicker than the contact portion of the contact member.