DE2000938A1 - Gas device with piezoelectric gas lighter - Google Patents

Description

Gas device with a piezoelectric gas lighter

The invention relates to a gas device with a piezoelectric gas lighter and relates in particular to the gas lighter piezoelectric generator.

Piezoelectric gas lighters have a piezoelectric generator, which is generated by mechanical stress on its piezoelectric Element or its combination of piezoelectric elements generates electrical power. This is in a one Burner spark gap assigned to the gas appliance, which is connected to the Terminal or the two terminal electrodes of the generator is connected, discharged in a spark. The spark ignites the gas. The mechanical stress or the tensioning of the or each piezoelectric element is usually carried out by Hand by means of actuators that compress or strike the or each element. This creates a spark discharge generated in the spark gap connected to the generator to ignite the gas. It is convenient to use the or any piezoelectric Element together with end caps made of metal and an electrode as a piezoelectric unit or generator for Assemble use in gas lighters.

009852/0235

The invention has its particular application in gas appliances, such as gas stoves with two or more gas burners that are to be ignited. Such gas appliances can have a spark gap associated with each burner. However, it is then required either

a) to provide a separate gas lighter for each burner, or

b) a gas lighter with an electrical outlet and a distributor to distribute the outlet to the various Spark gaps, or

c) to provide a lighter with more than one electrical output or

d) to ensure that two or more spark gaps at the same time through the output of a piezoelectric generator to Rollover to be brought.

The invention is based on the object of specifying a gas device and a piezoelectric generator suitable for this, in which the ignition of the burner according to the method described Alternative d) can be effected.

This problem is solved in a gas appliance with at least two burners, each of which is assigned a spark gap for igniting the gas, to which a gas lighter with a piezoelectric generator with at least one output is connected , in that the or each output or its two electrodes two series-connected spark gaps are closed, the electrical connection of which is ge earthed on the gas device, and that the or each piezoelectric element of the piezoelectric generator is isolated from earth (ground). This design of the gas appliance has the advantage that practically the same discharge conditions prevail at all spark gaps, regardless of environmental conditions and unavoidable pollution at the spark gaps. The same conditions do not exist when two series-connected spark gaps are connected to the output of a piezoelectric generator, the negative electrode of which is at ground potential and therefore the electrical connection of the two spark gaps with one another

cannot also be earthed. _v

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In the gas device according to the invention, on the other hand, neither of the two output electrodes is located at each output of the piezoelectric Generator at ground potential

For gas appliances with a number of burners, each Pair of spark gaps connected in series and connected to a piezoelectric output isolated from earth. Two or several pairs of spark gaps can be ignited by the same gas lighter, the gas lighter or its Generator has a suitable number of piezoelectric elements which are suitably insulated. The gas lighter can also be designed in such a way that different piezoelectric f generators are mechanically stressed simultaneously or one after the other · Finally, different gas lighters can be used for the different pairs of spark gaps.

A piezoelectric generator designed according to the invention has two metal end caps, at least one between them Pair of electrodes, at least one of the parts of the electrode or electrodes separating piezoelectric element and insulators for isolating the electrodes from the end caps and, if necessary the electrodes of different pairs,

Depending on how many spark gaps to ignite at the same time | are, the generator can have one of the following advantageous forms.

In a first embodiment, this is designed as a series stack of the following parts;

A first metal end cap, an insulator, a first electrode, a piezoelectric element, a second Electrode, a second insulator and a second metal end cap.

In a second embodiment of the piezoelectric generator, which is particularly suitable for igniting the four burners

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a gas stove with four burners is the piezoelectric one Generator designed as a series stack of the following parts:

A first metal end cap, a first insulator, a first electrode, a first piezoelectric element, a second electrode, a second insulator, a third electrode, a second piezoelectric element, a fourth electrode, a third insulator and a second metal end cap.

In a third advantageous embodiment, which Particularly suitable for gas stoves with which from the four If the four burners are to light an oven and a grill, the piezoelectric generator as a series stack is as follows Parts trained:

A first metal cap, a first insulator, a first electrode, a first piezoelectric element, a second electrode, a second insulator, a third electrode, a second piezoelectric element, a fourth electrode, a third insulator, a fifth electrode, a third piezoelectric element, a sixth electrode, a fourth insulator and a second metal end cap.

The parts of the series stack of the generator, i.e. the end caps, insulators, electrodes and peizoelectric elements are expediently held together by a housing made of iaiierendem material from which the connection electrodes protrude. A housing made of a thermoplastic material which shrinks during curing has proven to be expedient, its material on-the parts of the series stack is poured or pressed or applied in any other suitable form. Appropriate the housing engages in recesses provided on the outwardly facing outer surfaces of the end caps so as to Keep series stacks together. Certain types of nylon have proven to be particularly advantageous, such as nylon 610 and nylon 12

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or nylon 66. The outer end caps of the stack expediently have a circumferential groove on the outside into which the Housing engages to compress the stack as it shrinks and then hold it together.

At the output or the output electrode pair of an inventive piezoelectric generator for a gas lighter can only be connected to a single spark gap ' which is useful, for example, when an odd number of spark gaps is to be connected.

With the above-second advantageous embodiment - "the first and second electrodes form a first insulated terminal output, coupled to the two spark gaps in series, 'and the third and fourth electrodes a second insulated \ connection output to be connected connected to the two further radio links consecutively so that all the spark gaps assigned to the four burners of the gas stove can be ignited at the same time.

The invention and advantageous details of the invention are illustrated in several exemplary embodiments with reference to drawings explained in more detail.

Show it:

Fig. 1 shows the circuit of a not designed according to the invention Gas appliance;

FIG. 2 shows an equivalent circuit diagram for FIG. 1; FIG. 3 shows the circuit of a gas appliance according to the invention; FIG. 4 shows an equivalent circuit diagram for FIG. 3; FIG.

Fig. 5 shows a gas lighter in cross section, as it is in the Circuits according to Figures 3 and 4 can be used;

6 shows a piezoelectric generator with an output with isolated electrodes;

Fig. 7 shows another embodiment of a piezoelectric Generator with an output with two insulated electrodes;

009852/0235

Ill) t

Fig. Θ a piezoelectric generator according to the invention with two outputs with two electrodes each;

9 shows a piezoelectric generator according to the invention with three outputs with two electrodes each;

10 shows a gas lighter with actuation of the generator by means of a spring-loaded hammer;

11 shows a gas lighter with actuation of the generator by means of a cam;

12 shows a connection diagram for a gas lighter with a generator according to FIG. 8, and FIG

13 shows a connection diagram for a gas lighter with a generator according to FIG.

In the case of the gas lighter shown in FIG. 1, that generated by the generator 1 by mechanical actuation is indicated Potential delivered to two series-connected spark gaps 2 and 3, the burners of a gas appliance, not shown assigned. When the piezoelectric generator 1 is actuated once, sparks should be in both spark gaps

2 and 3 are generated · In Fig. 2 the equivalent circuit diagram of a gas device with the piezoelectric generator 1 and the two spark gaps 2 and 3 is shown, from which it can be seen that the provided insulators are bridged by resistors lying to earth. The value of these resistances varies with humidity and is also influenced by the dirt deposited on the insulators. For the purposes of illustration only, it is assumed that. these leakage or shunt resistances each have the value R. It can be seen from FIG. 2 that the spark gap 3 is shunted with a resistance of the value Rp, while the spark gap 2 is shunted by a resistor with the value 3R ₂ . It follows from this that the spark gap 2 is normally ignited before the spark gap 3 and thereby the Schunt impedance or the Schunt resistance to the spark gap

3 is further reduced and thereby the ignition of the spark gap 3 is made even more difficult than it is made more difficult _{by 3R 2 anyway.} It follows that even if the spark gap 2 is reliable

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ORlGlNAL INSPECTED

can be ignited, it is difficult to ignite also for the spark gap 3, namely the spark gap closer to the earth potential, each tit to effect security.

3 and 4 show the design of a Gac device according to the invention with a piezoelectric device according to the invention Gas lighter generator shown, in which the system is not asymmetrically earthed but rather the electrical connection earthed between the two spark gaps and the piezoelectric generator 1 is isolated from earth. Fig. 4 again shows the equivalent circuit diagram, in which R denotes the leakage or shunt resistance to earth. From Fig. 4 one recognizes that the Schunt resistance to earth for both Spark gaps 2 and 3 have the value R. It has been found that this arrangement provides a significantly more reliable ignition of the second spark gap ensures. In this arrangement, the electrodes can be an insulated one for each spark gap Electrode and on the other hand represent the torch body itself. The risk of ignition deterioration due to moisture and the effect of dirt on the insulators on the burners is reduced since only one insulator is provided for each burner will.

FIG. 5 shows a piezoelectric gas lighter such as can be used in the arrangement according to FIG. 3. The gas lighter includes a piezoelectric generator, both terminals of which are isolated from earth. Inside an insulation body B a housing C made of steel is anchored. The piezoelectric generator comprises two lead-zirconate-titanate ceramic piezoelectric elements P ^ and P «, their poles of the same name on the opposite sides of a connector T made of brass. On the two opposite sides of the generator an end cap E made of steel is fastened in each case and the entire unit is embedded in a housing N made of nylon, which is used in the Curing or heat treatment (setting) shrinks around the series stack formed by the individual parts mentioned

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ORiGiNAL INSPECTED

Gripping on the end caps to hold tightly together. The gas lighter further comprises an actuator with a spring-loaded hammer H which is disengaged by a handle, not shown can be and is isolated. By unlatching the hammer and hitting it on the piezoelectric generator a potential for a spark between the housing C and the Terminal T, which form the output terminals of the igniter 1 according to FIG. 3, is generated.

FIG. 6 shows another embodiment of a piezoelectric generator according to the invention, which is suitable for use in the arrangement according to FIG. This generator comprises a stack of the following parts: an end cap 4 made of steel, a first ceramic insulator 5 _f, a first electrode 6 made of brass, a piezoelectric lead-zirconate-titanium-at-ceramic element 7, a second electrode 8 made of brass, a second ceramic insulator 9 and a second end cap 10 made of steel. Both end caps have a circumferential groove 11, and the series stack is embedded in a housing 12 made of nylon of type 610 or type 12, which shrinks when it solidifies and thus holds the stack tightly together. Squeezing or hitting the end caps, even in a light that connects them to earth, allows an output potential to be picked up from electrodes 6 and 8, both of which are isolated from earth.

In Fig. 7 an arrangement with two piezoelectric units of the type shown in Fig. 5 is shown, which allows to gain a single output isolated from ground without isolating the metal housing, not shown. The two units 13 and 14 each have two piezoelectric lead-zirconate-titanate ceramic elements 15, 16 mounted back to back against the brass electrode 17 disposed between them. There are also end caps 18 and 19 are provided and each unit is embedded in a housing 20 made of nylon. The two units result in output potentials

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of opposite polarity and are so mounted with their ends against each other that they are pressed against each other so that their adjoining end caps are in electrical contact with one another, the other two end caps can but do not have to be grounded. It can be seen that with this arrangement an isolated output through the two electrodes 17 is formed.

Figo 8 shows a preferred embodiment of the invention, as its piezoelectric generator two against earth and against each other provides isolated outputs. This piezoelectric - f generator for a gas lighter consists of a series stack, which includes the following items:

A first end cap 21 made of steel, a first ceramic insulator 22, a first electrode 23 made of brass, a first = piezoelectric lead-zirconate-titanate ceramic element 24, a second electrode 25 made of brass, a second ceramic insulator 26, a third electrode 27 made of brass, a second piezoelectric lead-zirconate-titanate ceramic element 28, a fourth electrode 29 made of brass, a third ceramic insulator 30 and a second end cap 31 made of steel. The stack is embedded in Type 610 or Type 12 nylon. The two outputs are formed like by the electrodes 23 and 25 or 27 and 29th

Another embodiment of a piezoelectric generator according to the invention for a gas lighter is shown in FIG. 9 which largely resembles the embodiment of FIG. 8 and in which therefore the same parts are provided with the same reference numerals. The main difference is that a further piezoelectric element 45 and associated fifth and sixth electrodes 47 and 46 and another ceramic one

Insulator 48 between the second end cap 31 and that on the third Insulator 30 adjacent third piezoelectric element with electrodes 46 and 47 are provided.

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In Fig. 10 is a preferred way of confirmation and the stress on one of the generators according to FIGS. 6 to 9. A generator 32 is in a gas lighter body 33 is provided, which is grounded to the gas appliance. An anvil 34 is secured in the body 33 on one side and on the other Side a hammer 35 is provided. By means of operating parts, not shown, the hammer can counter the force of a hand Spring 36 to be withdrawn. If this is then suddenly disengaged, it strikes the generator 32 and thereby causes the Generation of the spark potential.

Another possibility of actuating or stressing a generator 32 is shown in FIG. 11. Here is this one provided so that it can be tilted around its one end 37 on a joint 38. The hinge 38 is grounded to the lighter body. The nylon case does not encompass the end faces of the end caps of the generator but rather only engages in a groove in the outer wall of the end caps. The generator 32 is also grounded with respect to a cam 39 which can be actuated manually by a lever arm AO, by operating it, the generator can be tilted. This will compress the generator and the desired Spark potential generated.

FIG. 12 shows the electrical connection of the generator shown in FIG. 8 with four spark gaps Gas stoves with four burners or burners, the four spark gaps are divided into two pairs 41 and 42 as well as 43 and 44. The first pair of spark gaps is connected in series to electrodes 23 and 25 and the second pair of spark gaps in FIG Connected in series to electrodes 27 and 29. The electrical connection of the spark gaps 41 and 42 and 43 and 44 is grounded to the gas appliance. By triggering the hammer 35 of the gas lighter according to FIG. 10, at the same time Sparks generated in all four spark gaps. Regardless of which burner it comes from, gas is ignited.

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The circuit diagram according to FIG. 13 is used for the generator according to FIG. 9 and thus not only allows the ignition of the four Burner at the four burners of the gas stove but also the burner, its grill "and its oven. The arrangement is this same as those according to FIG. 12 with the exception of the additionally provided electrodes 46 and 47 to which the connected in series Spark gap 49 for the grill and spark gap 50 for the oven are connected.

Claims 009852/0235

Claims (7)

DR.ING. P. WUBSTHOPF DIPL. ING. G. PULS SCnwEIOEHSTHAMX U n _ _ DII.K.T.PECH MANN TCLsron C2 0esi £ U U U 9 3 O DH. ING. D. KKIIRENS rn.roi.iHH.Di.rMi, PATENTiIlWlLTI motbotpatkiit mCkckm 1A / G-37 386 claims 1.1 Gas appliance with at least two burners, each of which is assigned a spark gap for igniting the gas, to which a ' Gas lighter is connected to a piezoelectric generator with at least one output, characterized in that the or each output or its two series-connected spark gaps are connected to the two electrodes, their electrical connection to the Gas appliance is earthed and that the or each piezoelectric element of the piezoelectric generator is connected to earth (ground) is isolated. 2. Gas device according to claim 1, characterized in that the piezoelectric generator has two Metal end caps (4, 10; 18, 19; 21, 31) between them at least one pair of electrodes (6, 8; 17; 23, 25; 27, 29; 46, 47), at least one of the parts of the electrode or electrodes from one another separating piezoelectric element (7; 15, 16; 24, 28, 45) and insulators (5, 9; 22, 26, 30, 48) for insulating the electrodes of the end caps and optionally the electrodes of different pairs. 3 · Gas device according to claim 2, characterized in that the piezoelectric generator as Series stack of the following parts is formed in the following order: a first end cap (4) made of metal, an insulator (5), a first electrode (6), a piezoelectric element (7), a second electrode (8), a second insulator (9) and one second end cap (10) made of metal (Fig. 6). - 2 009852/0235 4. Gas device according to claim 2, characterized · that the piezoelectric generator as Series stacks of the following parts formed in the following order is: a first end cap (21) made of metal, a first insulator (22), a first electrode (23), a first piezoelectric element (24), a second electrode (25); a second insulator (26), a third electrode (27), a second piezoelectric element (28), a fourth electrode ί (29), a third insulator (30) and a second end cap (31) made of metal (Fig. 8). 5. Gas device according to claim 2, characterized in that the piezoelectric generator is designed as a series stack of the following parts in the following order: a first end cap (21) made of metal, a first insulator (22), a first electrode (23), a first piezoelectric element (24), a second electrode (25), a second insulator (26), a third electrode (27), a second piezoelectric element (28), a fourth electrode (29), a third insulator (30), a fifth electrode (47), a third piezoelectric element (45), a sixth electrode (46), a fourth insulator (48) and a second end cap (31) made of metal (Fig. 9). Ä 6. Gas device according to one of claims 2 to 5, characterized characterized in that the end caps, insulators, electrodes and piezoelectric elements from a housing (12, 22) made of insulating material, from which the electrodes protrude, are held together. 7. Gas device according to claim 6, characterized in that the housing (12, 22) consists of one when solidifying or curing consists of shrinking thermoplastic material which is poured onto the parts of the series stack or is pressed, and that the housing in on the outside 009852/0235 - 3 - facing outer surfaces of the end caps engages provided recesses in order to hold the series stack together. 8, gas device according to claim 6 or 7, characterized in that g e k e η η draws that nylon is used as a thermoplastic material. 1058 009852/0236 ORIGINAL INSPECTED