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Publication numberUS3588553 A
Publication typeGrant
Publication dateJun 28, 1971
Filing dateOct 8, 1969
Priority dateOct 19, 1968
Also published asDE1804100A1
Publication numberUS 3588553 A, US 3588553A, US-A-3588553, US3588553 A, US3588553A
InventorsMobus Gunter, Westphal Dieter
Original AssigneeVaillant Joh Kg
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Piezoelectric lighter
US 3588553 A
Abstract  available in
Images(1)
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Claims  available in
Description  (OCR text may contain errors)

United States Patent [72] Inventors Dieter Westphal I Huckerswagen;

Gunter Mobus, Wermelskirchen. Germany [21] Appl. No. 864,806

[22] Filed Oct. 8, 1969 [45] Patented June 28,1971

[73] Assignee Joh. Vaillant, KG

Remscheid, Germany [32] Priority Oct. 19, 1968 [33] Germany {54] PIEZOELECTRIC LIGHTER 9 Claims, 6 Drawing Figs.

[52] U.S. Cl SIG/8.7, 317/79, 431/255 [51] lnt.Cl 110lv 7/00 [50] Field of Search 310/8],

[56] References Cited UNITED STATES PATENTS 3,428,408 2/1969 Ameyama et a1. 431/255 3,509,388 4/1970 Mifune et a1 310/8.7

Primary Examiner-D. F. Duggan Assistant Examiner-B. A. Reynolds Attorney- Darbo, Robertson & Vandenburgh ABSTRACT: A cylindrical casing has an anvil in one end held in place by inwardly projecting portions of the casing. A piezoelectric element in the casing abuts the anvil and has its actuating pin extending in the other direction. A washer bearing on casing portions and a Belleville spring between the washer and the element encircle the pin and urge the element against the anvil. A striker has a head against the pin and a post extending in the other direction. A spring encircles the post and bears on a disc restrained by the casing and against the head to urge the striker towards the pin. The other end of the casing forms a sawtooth cam on which rides a cam follower attached to the post. The cam follower is connected to a rotatable cap for rotation therewith while permitting axial movement of the follower in the cap.

PAT E NT EU JUN28 19?:

0/5751? I/VESTPHAL GUN TER M0505 IN VEN TORS BACKGROUND AND SUMMARY OF THE INVENTION coupling, overcoming the action of a spring. When the spring is prestressed to a given extent, the coupling is released and the striker engages the piezoelectric element. The coupling is a ball-and-socket joint with a ballresiliently engaging in a groove in the striker. The axial force spring tension) which i must be applied before the ball (detent) is forced back out of the groove depends on the geometry of the relatively small ball and of the groove. Therefore, under ordinary manufacturing practices, it cannot be precisely defined. Also, strong contact pressures act on the detent and on the groove, so that the coupling is subjected to considerable abrasion. Lastly, it is possible to withdraw the manipulator only part way and then to let it go without releasing the coupling, so that the blow on the piezoelectric element is weaker and one cannot tell whether or not an ignition spark has been produced. This can be a disadvantage in many cases. Moreover, all the spring force for prestressing the striker must be applied by the operator directly and manually in an axial direction.

In another prior arrangement (Austrian Pat. No. 261,791), a piezoelectric element which is fixed relative to a casing is embraced at one end by a radially expansible, cup-shaped pressure sleeve and at the other by a cup-shaped striker. The

striker is biased by a first spring and has a radial flange on which the edge of the pressure sleeve comes to bear when pushed down in opposition to the action of a second spring. When the pressure sleeve has pushed the striker down to a certain extent and prestressed the first spring, it is expanded by means of inclined surfaces so that its edge slides off the flange of the cup-shaped striker and the latter strikes the piezoelectric elementunder the influence of the prestressed first spring.

This prior arrangement is a very complicated design, with its piezoelectric element mounted centrally in the casing and embraced from both ends. With this arrangement, too, the entire prestressing force must be applied directly and axially by the operator. To this force is added the force required for radial expansion ofthe edges of the pressure sleeve.

The problem underlying the invention is that of creating a piezoelectric lighter which is both simple and strong in construction.

Another problem underlying the invention is that of creating a piezoelectric lighter which ensures that precisely defined blows will fall on the piezoelectric element.

A further problem underlying the invention is that of creating a piezoelectric lighter which requires relatively little force in order to operate it.

A last problem underlying the invention is that of creating a piezoelectric lighter in which the striking mechanism may be a separately manufactured unit.

In the present invention the manipulator is a rotatable control grip to which the striker is connected in such a way that it is axially movable but not rotatable with respect to the grip, and during its rotation along with the grip the striker is axially moved by a follower riding along an extending sawtooth cam fixed relative to the casing.

The blow then falls in a precisely defined manner as the follower slips down over the steep edges of the sawtooth cam. The arrangement is very simple and sturdy in construction, since it does not require either unreliable ball-and-socket joints or a central mounting for the piezoelectric element. The

axial force for prestressing the spring acting on the striker is generated by way of the gently inclined surfaces of the sawtooth cam, and the manually exerted force may be further reduced by means of a lever on the control grip if necessary.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal section through the piezoelectric lighter;

FIG. 2 is a section along the line A-A of FIG. 1;

FIG. 3 illustrates the position of the lighter element in the casing by means of a section along the line B-B of FIG. 1;

FIG. 4 is a section along the line C-C of FIG. 1;

FIG. 5 is a partial section showing a part of the lower portion of FIG. I, seen in the direction D of FIG. 1; and

FIG. 6 is a diagrammatic illustration of the sawtooth cam developed in a plane.

DESCRIPTION OF A SPECIFIC EMBODIMENT The following disclosure is offered for public dissemination in return for the grant of a patent. Although it is detailed to ensure adequacy and aid understanding, this is not intended to prejudice that purpose of a patent which is to cover each new inventive concept therein no matter how others may later disguise it by variations in form or additions or further improvements. The claims at the end hereof are intended as the chief aid toward this purpose, as it is these that meet the requirement of pointing out the parts, improvements, or combinations in which the inventive concepts are found.

A frame is formed by a casing l which is tubular in form and closed at one end by a cylindrical anvil 2. The anvil 2 has an annular groove 2', into which extend a plurality of casing portions 1' spaced around the periphery of the casing. The anvil 2 also serves as the tool punching die for the cutting and stamping punches (not shown) which are applied to the outside of the tubular casing l to force the projections 1 into groove 2'. These punches cut the long sides of the casing portions 1 and at the same time press them into the annular groove 2' in the anvil 2 during the manufacturing operation. The anvil is then fixed without clearance in the casing 1, in such a way that it cannot be displaced.

The piezoelectric element 4 bears on the anvil 2 by way of its foot 3. The element 4 has a square cross section (FIG. 3), and its four corners 4 guide it in the casing l. A disc is held against movement away from the element by inwardly projecting projections 7 of the casing. A Belleville spring 5 bears on disc 6 and urges the element 4 against the anvil. The striker pin 8 of the lighter element 4 projects through central openings in the disc 6 and spring 5.

The high-tension lead 9 runs from the side of the lighter element 4. To permit the lighter element 4 to be inserted in the casing 1, the casing, if made from tubing, is slotted at 10 on one side. In the present embodiment the casing l is made by forming a flat sheet into a tube. The edges which then lie opposite one another are graduated in length, so that, when bent into a tube, parts of them are about in contact (10 in FIG. 3) and parts form the slot 10 (FIGS. I and 2) for the shoe 9 of the cable 9.

When the striker head 12, which is biased by the coil spring 11, is in its position of rest, it bears on the element pin 8. The spring 11 biasing the striker is supported at its other end on a disc 14. Disc 14 in turn bears on inwardly extending stamped out portions 15 of the casing l. The rotatable control grip 16 is fixed to the disc 14. This grip comprises an outer, cup-shaped sleeve I6 and two abutments 16" (FIG. 4) which are symmetrically positioned relative to one another. The abutments are secured to the base of the sleeve 16'. They are semi-cylindrical and define a gap 16" between them. Advantageously, the grip l6 and its elements 16 are made in one piece from a synthetic plastic material. At their distal ends, the abutments 16" have integral posts 17 (FIG. 5), which extend through two symmetrically positioned holes in the disc 14. The ends of posts 17 are hot worked to form rivet-head-like portions 17.

After insertion of the coil spring 11, the post 12' of the striker 12 is passed through the opening opening 13 in the disc 14 until it projects into the rotatable grip 16. The post 12' is then twisted so that the opening 12" adjacent its end is flush with the gap 16. The crosspin 18 (a slotted pin) is then pushed into the opening 12". All the components of the striking mechanism 19 are now connected together to form a single structural unit.

That end of the casing which serves to receive the striking mechanism 19 forms a sawtooth cam comprising cam surfaces 21 inclined with respect to the axis of the casing and edges 22 parallel to said axis. The inclined surfaces 21 are joined to edges 22 at outwardly extending noses of the cam. The surfaces 21 and the edges 22 lie opposite one another, respectively, on the tubular end of the casing, i.e. there are two surfaces 21 which are 180 apart.

In assembly, the striking and manipulator mechanism 19 is introduced into the casing 1 until the striker head 12 bears on the element pin 8. With the spring 11 in place, the disc 14(already secured to cap 16) is placed over post 12' and pin 18 (forming a cam follower) is inserted through the post. The disc is then pushed in until it reaches its assembled position. The prepared casing portions are then pushed from outside into the bearing groove 15 formed by the disc 14 and by shoulders 16"" on the abutments 16". The disc 14 is now supported, and the grip 16 can rotate in this bearing without moving axially.

To produce a piezoelectric ignition spark, the rotatable control grip 16 is turned. The turning of the control grip rotates pin 18 relative to casing l. The grip can turn in one direction only: the direction in which the follower 18 moves up the inclined surface 21 (downwardly in FIG. 1). Upon reaching the outwardly extending noses of the cam where the surfaces 21 join the edges 22, the follower 18 is free to return in an axial direction allowing striker 12, 12 to be forced against pin 8 by spring 11. As a result of the force of the coil spring 11, the striker head 12 impacts against pin 8 of the lighter element 4. The high tension passed to the spark gap along the lead 9 produces an ignition spark. To produce another ignition spark, the control knob is again turned in the same direction.

We claim:

1. In a piezoelectric lighter comprising a piezoelectric element member and a striker member, a frame, one of the members being movably mounted on the frame for movement toward and away from the other member, and a spring resiliently urging the one member toward the other member, the improvement comprising:

said frame being in the form of a tubular casing having two ends and an axis between the ends, said other member being within said casing and adjacent one end of the easing, said one member being within said casing and between the other member and the other end of the easing, said spring being within the casing and at least partially between said one member and the other end of the casing, said other end of the casing defining a sawtooth cam having first edges inclined with respect to said axis and second edges substantially parallel to said axis, cam follower means secured to said one member and contacting said cam for moving said one member away from the other member against the urging of said spring as the follower means is rotated with respect to said casing and thereafter releasing said one member for movement toward the other member by said urging, and a cap about said other end of said casing, rotatable with respect thereto and operatively connected to said cam follower means for rotating the cam follower means.

2. In a lighter as set forth in claim 1, wherein said cap has two spaced semicylindrical abutments positioned within said other end of said casing, said follower means including a pin normal to said axis, connected to said one member and positioned in said cap in the space between said abutments.

3. In a lighter as set forth in claim 2, wherein said cam has two of said inclined surfaces spaced about said axis apart. 4. In a lighter as set forth in claim 2, wherein said abutments have posts at the distal end thereof which posts project into said casing parallel to said axis, a disc attached to the distal end of the posts, said disc having a central opening, said cam follower means comprising a post extending through said spring and opening, said pin being attached to the latter post adjacent the distal end thereof, said casing having inwardly projecting portions between said disc and the distal ends of the abutments to restrict said cap against axial movement while allowing rotational movement thereof.

5. In a lighter as set forth in claim 4, wherein said one member is the striker member, and including an anvil in said casing at said one end thereof, said anvil having an annular groove therein, said casing having inwardly projecting portions extending into said annular groove to lock said anvil to the casing against axial movement, said element member abutting said anvil.

6. In a lighter as set forth in claim 5, wherein said element member includes an actuating pin extending from the end thereof adjacent said striker member, said frame includes a second disc having a central opening, said second disc being positioned in said casing between said striker member and element member with said pin extending through said central opening therein, said casing having inwardly projecting portions against which said second disc seats and restrains movement of the second disc in a direction away from said element member, and a Belleville spring between said second disc and said element member.

7. In a lighter as set forth in claim 1, wherein said one member is said striker member, and including an anvil in said casing at said one end thereof, said anvil having an annular groove therein, said casing having inwardly projecting portions extending into said annular groove to lock said anvil to the casing against axial movement, said element member abutting said anvil.

8. In a lighter as set forth in claim 7, wherein said element member includes an actuating pin extending from the end thereof adjacent said striker member, said frame includes a disc having a central opening, said disc being positioned in said casing between said striker member and element member with said pin extending through said central opening therein, said casing having inwardly projecting portions against which said disc seats and restrains movement of the disc in a direction away from said element member, and a Belleville spring between said disc and said element member.

9. In a lighter as set forth in claim ll, wherein said element member includes an actuating pin extending from the end thereof adjacent said striker member, said frame includes a disc having a central opening, said disc being positioned in said casing between said striker member and element member with said pin extending through said central opening therein, said casing having inwardly projecting portions against which said disc seats and restrains movement of the disc in a direction away from said element member, and a Belleville spring between said disc and said element member.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3800171 *Oct 18, 1972Mar 26, 1974Matsushita Electric Ind Co LtdDevice for generating high voltage
US4523261 *Aug 5, 1982Jun 11, 1985West Philip GLight source, manually operated
Classifications
U.S. Classification310/339, 431/255, 361/260
International ClassificationF23Q3/00
Cooperative ClassificationF23Q3/002
European ClassificationF23Q3/00A