DE1804100A1 - Piezoelectric ignition device - Google Patents

Description

Joh, V-aillant KG ₁ Hem see id

Piezoelectric ignition device

The invention relates to a piezoelectric ignition device, consisting of a piezoelectric element, which with a spark gap, one in the direction of that piezoelectric element spring-loaded striking member and a handle, through which a retraction of the striking member against the spring load and subsequent rapid acceleration of the same to generate a blow on the piezoelectric Element is triggered.

In a known device of this type (British patent specification 1 092 535) the impact member is connected to an axially pull-out handle via a releasable coupling. When pulling out the handle, the impact member is initially taken along via the coupling against the action of a spring. When the spring is preloaded to a predetermined level, the clutch is released and the striking link falls on the piezoelectric element. The coupling is a ball coupling with a resilient in a groove of the impact member engaging ball. The axial force (spring tension) at which the ball is pushed back depends on the geometry the relatively small ball and groove and is therefore not accurate definable. Strong surface pressures also act on the detent or coupling ball and the groove, so that the coupling is subject to great wear. Finally, it is possible to just one handle without releasing the clutch Pulling the piece out and then releasing it, applying a lighter blow to the piezoelectric element and you then cannot say whether an ignition spark has occurred or not.

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This can be disadvantageous in some applications. In the end the operator has the full spring force with which the impact member is to be pre-tensioned, directly by hand in an axial direction Direction to bring up.

An arrangement is also known (Austrian patent specification 261 791), in which a piezoelectric element fixed to the housing is on one side of a radially expandable, cup-shaped pressure sleeve and on the other side of a cup-shaped striking member is encompassed. The flapping link ^ is under the influence of a first spring and has one

radial flange on which the edge of the Dwckhülse at the depression of which comes to rest against the action of another spring *. After the pressure sleeve then the hammer has depressed a certain distance and preloaded the first spring, the pressure sleeve is over inclined surfaces spread apart, so that its edge slides off the flange of the pot-shaped striking member and the latter below the influence of the pretensioned first spring on the piezoelectric Element hits.

This known arrangement is structurally quite complicated with the Centrally held in the housing piezoelectric element, which is gripped from both sides. Here, too, must be done by the operator the entire preload force can be applied directly axially. On top of that there is the strength that is required to achieve the Spread the edges of the pressure sleeve radially apart.

The invention is based on the object of creating a piezoelectric ignition device which is simple and robust in construction.

The invention is also based on the object of a piezoelectric To create ignition device that ensures the exertion of precisely defined impacts on the piezoelectric element.

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The invention is also based on the object of providing a piezoelectric To create ignition device which requires a comparatively low actuation force.

The invention is finally based on the object of a piezoelectric To create an ignition device in which the striking mechanism can form a unit that can be produced by itself.

The invention consists in that the handle is a rotary handle with which the striking member is non-rotatably but axially movably connected , and that the striking member is rotated with a g

Driver is guided along axially extending sawtooth curves fixed to the housing.

The impact then occurs when the driver slips over the steep edge of the sawtooth curves in a more precisely defined manner Way. The structure of the arrangement is very simple and stable, since neither sensitive ball couplings nor a central one Bracket of the piezoelectric element are required. The axial force to pre-tension the acting on the striking link Spring is generated via the flat inclined surfaces of the saw-tooth curve and the force to be exerted by hand can optionally be carried out by a lever seated on the handle can be further reduced.

An embodiment of the invention is explained in more detail below with reference to the accompanying drawings.

1 shows a piezoelectric ignition device in longitudinal section;

Fig. 2 is a section on line A-A of Fig. 1;

Fig. 3 shows the position of the ignition element in the housing along section line B-B of Fig. 1;

Figure 4 is a section on line C-C of Figure 1; Fig. 5 is a portion of the lower part of Fig. Γ

in viewing direction D; . -. .

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BATH ORIGINAL

Fig. 6 shows schematically the developed in the plane saw-toothed cams.

In Fig. 1, the housing 1 is tubular and at one end by a cylindrical anvil 2; locked. The anvil 2 has an annular groove 2 ' into which a plurality of jacket sections' distributed around the circumference of the housing are pressed. In this case, the anvil 2 is at the same time the tool punching die for the cutting dies that attack the tubular housing 1 from the outside. These intersect the longitudinal sides of the V MantelabsehMtte and presses the same at the same time into the annular groove 2 'of the anvil 2 in. See also Fig. 2 _f Therefore, the anvil sits imversehiebbar and fixed without play in the housing 1.

With its base 3, the piezo element 4 rests on the anvil 2 ah. It is designed as a square body, see Fig. 3, and is carried along with it. its four corners 4 'in the housing 1. At its other end, the ignition element 4 is supported on the disk 6 via the spring washer 5. This is due to several cut out of the housing jacket 1 and inwardly deformed punches 7. The firing pin 8 of the ignition element 4 protrudes through the middle opening of the disk 6.

The high-voltage cable 9 is led out on the side of the ignition element 4. In order to be able to introduce the ignition element 4 into the housing 1, the housing 1, if it is made of a tube, must ah the Installation side are slotted, 10. In the present case, the housing 1 is formed from a flat plate to form a tubular body. The edges that are opposite each other are offset along their length, so that after bending these edges partly touch each other, see 10 'in FIG. 3, and partly form the aforementioned slot 10 for the shaft 9' of the cable 9.

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The flapping link loaded by the helical spring 11 is in the rest position 12 on firing pin 8. The helical spring 11 loading the impact member is supported with its other end on one Washer 14. The disk 14 for its part rests against indentations in the housing 1. At the same time, the rotary handle is on the disk 14 16 attached. This consists of an outer cup-shaped sleeve 18 * and two webs 16 ″, see FIG. 4, which are symmetrical lie to each other, sit at the bottom of the sleeve 16 'and leave a gap 16 "* form. The twist grip 16 and its webs 16 "are advantageous. made of one piece and made of plastic. This allows you to easily do the foregoing Ends of both webs 16 ″ taper like a pin, see 17 in Fig. 5, these pins through two coincident openings in the Insert disk 14 and the ends of the pins like a rivet head, 17 ', thermoforming.

After inserting the helical spring 11, the plunger 12 'of the Striking member 12 pushed through the opening 13 of the disc 14 until it protrudes into the rotary handle 16. Then will the plunger is rotated so that its opening 12 "at the end is aligned with the gap 16 '" and the transverse pin 18 (toggle grooved pin) can be inserted into the opening 12 ″. As a result, all parts of the striking mechanism 19 are connected to one another to form a structural unit.

The end of the housing, which serves to accommodate the striking mechanism 19, is provided with cams 20 on the front side, see also FIG. 6, which are sawtooth-like and form inclined planes 21. The inclined planes are joined by axially parallel ones without a transition Edges 22 on. The curves 21, 22 are opposite one another at the tubular end of the housing.

For installation, the hammer mechanism 19 is inserted into the housing 1 until the striker 12 rests on the striker 8. The twist grip

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with the disk 14 is pressed in until the disk 14 reaches its installed position. Then the prepared ones from the outside Jacket section 5 'in which by washer 14 and web shoulders 16 "" formed bearing groove 15 'pressed. The disk 14 thus comes to rest and the rotary handle 16 moves in a rotating manner without an axial stroke in this camp.

To generate a piezoelectric ignition spark, the twist grip 16 is turned. The rotation is only possible in one sense, in such a way that the transverse pin 18, the inclined plane 21, s. Fig slides up. '·. At the end of the inclined surface 21, the pin 18 leaves the same in the axial direction without hindrance. With the force of the helical spring 11, the striking member 12 is hurled against the striking pin 8 of the ignition element 4. The high voltage conducted to the ignition gap via the cable generates an ignition spark. To generate a new ignition spark, turn the rotary knob in the same way.

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Claims (6)

** 18UA1Ü0 patent claims 1. Piezoelectric ignition device, consisting of a piezoelectric Element which is connected to a spark gap, a spring-loaded in the direction of the piezoelectric element Beater and a handle through which a retraction of the impact member against the spring load and subsequent rapid acceleration of the same to generate a blow on the piezoelectric The element can be triggered, characterized in that the handle is a rotary handle (16) with which the striking member (12) is non-rotatably, but axially movably connected, and that the impact member (12) on rotation with a driver (18) is guided along axially extending sawtooth curves (21, 22) fixed to the housing. 2. Piezoelectric ignition device according to claim 1, characterized in that that a cylindrical housing (1) at its one edge two sawtooth-shaped offset by 180 relative to one another Cam (20) has that as a driver a transverse pin (18) of the striking member (12) under the influence of a on the striking member (12) acting helical spring (11) rests on the cam, and that the rotary handle (16) in the housing (1) protruding half-shell-shaped Has webs (16 "), which between them a Form gap (16 "') in which the transverse pin (18) is guided." 3. Piezoelectric ignition device according to claim 2, characterized in that a disc (14) sits on the tapered ends (17) of the webs protruding into the housing (1), behind which indentations (15) of the housing jacket (1) for the rotatable, but axially secured holder of the rotary handle (16) and which is centrally penetrated by a plunger (12 *) connected to the transverse pin (18) on the one hand and to the striking member (12) on the other hand. 0 0 9 818/0529. ₂ _ SAD ORIGINAL 18G41U0 p 4. Piezoelectric ignition device according to claim 2 or 3, characterized in that in the end of the cylindrical housing shell (1) facing away from the cam (20) an anvil (2) provided with an annular groove (2 *) on the circumference is inserted and through into the annular groove (2 ') engaging impressions (1 *) of the housing jacket (1) is secured. 5. The piezoelectric ignition device according to claim 4, characterized in that an intermediate wall forming plate (6) on indentations or -stanzungen (7) abuts the housing jacket (1) and forms an abutment for a spring plate (5) which the piezoelectric element ( 4) which protrudes through a firing pin (8) through an opening of the disk (6) back, presses the anvil (2). 6. The piezoelectric ignition device according to claims 3-5, characterized in that a pressing on the jar member (12) spiral spring (11) is supported on the seated on the rotary handle (16) disc (14). 0 0 9 3 ' S' 3 5 2 3