US3893799A

US3893799A - Abrasive wheels for cigarette lighters and method of making same

Info

Publication number: US3893799A
Application number: US353990A
Authority: US
Inventors: Robert Hocq
Original assignee: Societe Franco Hispano Americaine FRANCISPAM
Current assignee: Societe Franco Hispano Americaine FRANCISPAM
Priority date: 1972-04-26
Filing date: 1973-04-24
Publication date: 1975-07-08
Anticipated expiration: 1992-07-08
Also published as: NL7305737A; IT982106B; CH563816A5; FR2181492A1; JPS4942466A; ATA364373A; FR2181492B1; AU5488173A; ES220879Y; GB1424549A; AT326390B; ES440588A1; CA995479A; ES220879U; BE798630A; JPS545345B2; DE2319924A1; HK55777A

Abstract

Abrasive wheel for cigarette lighters consists of cylindrical plate having teeth along one edge and a knurled outer cylindrical surface. The wheel may be formed by bending a strip into a cylinder or stamping a circular plate into the shape of a cup.

Description

1451 July 8,1975

Hocq

[54] ABRASIVE WHEELS FOR CIGARETTE 2,252,676 8/1941 431/139 LlGH-TERS AND METHOD OF MAKING 3,129,505 4/1964 COX ll3/i [6 D SAME 3,262,289 7/l966 Biesenbach 43l/277 [75] Inventor: Robert Hocq, Boulogne-sur-Seine, FOREIGN PATENTS ()R APPLICATIONS France 915,405 [/1963 United Kingdom 431/274 [73] Assignee: Societe Franco-Hispano-Americaine germany rance ggzg Sam 744,264 1/1933 France 431/140 [22] Filed: Apr. 24, 1973 I Primary ExammerCarroll B. Donty, Jr. PP 353,990 Attorney, Agent, or FirmBriseb0is & Kruger [30] Foreign Application Priority Data Apr. 26, 1972 France 72.14817 [57] ABSTRACT Abrasive wheel for cigarette lighters consists of cylin- 431/ 12 3 63; drical plate having teeth along one edge and a knurled 58] Fieid outer cylindrical surface. The wheel may be formed by 13"6 bending a strip into a cylinder or stamping a circular plate into the shape of a cup.

56 References Cited 1 U T STATES PATENTS 3 Claims, 5 Drawlng Figures l,951,l5l 3/l934 Hopkins ..1l3/ll6D 1 ABRASIVE WHEELS FOR CIGARETTE LIGHTERS AND METHOD OF MAKING SAME SUMMARY OF THE INVENTION This invention relates to abrasive wheels for cigarette lighters, that is to say, wheels which are adapted to frictionally engage a flint to ignite the lighter, as well as to methods of manufacturing these abrasive wheels.

Up to the present time these wheels for cigarette lighters have been made by cutting them from large steel rods and machining them. The machining consists essentially in forming a bearing in the wheel so that it may be mounted on a pivotal axis, cutting one of the faces of the wheel into ratchet teeth, and providing the necessary striations on the periphery of the wheel.

This process has certain serious disadvantages.

In the first place, the various machining operations lead to an important loss of the expensive material of which the wheel is made The principal disadvantage resides, however, in the fact that the various machining operations are time consuming, require complex tooling, and highly skilled labor, which results in a particularly high cost.

It has already been suggested that these abrasive wheels for cigarette lighters be made by stamping them from a plate followed by knurling of their external surfaces and nitrating.

This process is, however, scarcely satisfactory in the case of abrasive wheels for automatic lighters, that is to say, wheels driven by ratchet teeth, because it then necessitates the manufacture of a supplemental member provided with ratchet teeth, which cancels out the advantage of stamping.

This invention is intended to provide abrasive wheels for cigarette lighters which avoid these disadvantages as a consequence of a particularly simple structure, as well as methods of manufacture which make it possible to produce abrasive wheels for cigarette lighters at speeds heretofore unknown, with economies in material, machining, and skilled labor, so that the cost of the abrasive wheel may be reduced to a tenth of its present price,

It is an object of the present invention to provide an abrasive wheel for a cigarette lighter characterized by the fact that it comprises a metal plate bent into a cylindrical shape, with knurling on its external cylindrical surface and ratchet teeth integral with the plate extending along one of its edges.

In a first embodiment the annular cylindrical plate is discontinuous, the annular shape being produced by bringing the two ends of the plate together. These ends may advantageously be provided with reciprocal interfitting means.

In another embodiment, the wheel has a continuous annular shape and, on the edge free of ratchet teeth, terminates in a wall perpendicular to the axis of the wheel, which thus becomes cupshaped.

It is a further object of the invention to provide a method of manufacturing abrasive wheels for cigarette lighters characterized by the fact that a flat metallic plate of suitable dimensions and provided with teeth on at least part of its periphery is deformed to impart thereto the cylindrical shape of the wheel.

The toothed flat plate embodiment may advantageously be manufactured by cutting it out, for example in a transfer press, or in a cyclically operating tool.

In a first embodiment of the invention which is particularly useful, the plate is initially rectangular in shape, one of the longitudinal edges of the plate having teeth formed by shearing to constitute the ratchet teeth of the wheel. The plate is deformed by rolling it up to produce a closed cylindrical ring by bringing its two ends together.

Advantageously, two extreme ends of the rectangular plate may have mating recesses which interfit when the plate is rolled into a cylinder to prevent separation of these two ends.

In this first embodiment the different plates may be made from a strip of continuous metal which travels through a cyclically operating tool, the different successive plates being detached from each other during the final rolling operation which deforms the plate to impart thereto a cylindrical shape.

The plate is preferably knurled after it has been rolled into its cylindrical form.

In a second embodiment the flat plate is substantially circular in shape withh peripheral teeth, and this plate is stamped to form it into the shape of a cylindrical cup. In this embodiment, the flat plate may advantageously be formed by cutting the plate from a suitable metallic sheet, with the teeth remaining, after deformation, at the open side of the cylindrical cup thus formed.

Such a cup may be formed in a single stamping operation or preferably by several successive stamping operations, preferably in a transfer press.

Other advantages and characteristics of the invention will become apparent from a reading of the following description ofa preferred embodiment, given purely by way of illustration and example, with reference to the accompanying drawings on which:

FIG. 1 is a schematic view showing in perspective the different steps of the process according to the second embodiment of the invention;

FIG. 2 is a top plan view of the plate used in the process according to the first embodiment of the invention;

FIG. 3 is a side view of an abrasive wheel made from the plate of FIG. 2',

FIG. 4 is a diametral sectional view taken through the abrasive wheel of FIG. 3', and

FIG. 5 is an end view of the abrasive wheel of FIG. 3, which has been mounted on a sleeve to facilitate its attachment to a shaft.

Referring now to FIG. I, in this first embodiment of the invention a plate I, which is circular in shape, is preferably formed by stamping it from a sheet of suitable hard metal and the periphery of this plate has suitable teeth 2 which are to form the ratchet teeth of the abrasive wheel.

The plate I is stamped in a press to form a cylindrical cup, the bottom 3 of which corresponds to the central part of the flat plate, while the annular cylindrical part 4 thereof carries the teeth 2 on its free edge.

In a second stamping step the depth of the cylindrical part 4 is increaseed to form the cylindrical part 4' and in this state the stamped plate has practically the final dimensions of the abrasive wheel.

After this stamping a central orifice 5 may advantageously be punched in the bottom 3 to permit the ultimate mounting of the abrasive wheel.

The wheel made in this manner is then striated in a conventional machine to form the knurled surface 4'.

Referring now to FIGS. 2, 3 and 4, in this embodiment of the invention to a plate of substantially rectangular shape is formed from a strip of suitable hard metal. One of the longer sides of this plate is preferably provided with teeth 7 formed by shearing for example, while the two extreme ends of the plate 6 are cut out at 8 to form mating recesses which interfit when these two ends are brought together.

The plate 6 is then rolled up to impart thereto an annular cylindrical shape as shown on FIG. 3. At the end of the rolling operation the parts 9 of the two ends 10 engage in the recesses 8 so that the two ends are thus connected along a V shaped line shown in FIG. 3. For this reason simple friction of the flint against the wheel is incapable of opening up the cylinder formed by the plate, which will therefore always retain its cylindrical shape.

The plate may advantageously be cut in a cyclically operating tool, the different plates 6 being connected one behind the other by strips of metal which are eliminated during the rolling of the plate.

When the plate 6 has received it cylindrical shape of polygonal member 10 having an inner orifice H for mounting the plate on a suitable shaft is force-fitted into the cylinder.

This member 10 may be provided with a flange 12 extending outwardly in a plane perpendicular to its axis which bears against the surface 13 (shown only in FIG. 4) of the plate which is situated opposite toothed surface 7. After mounting the deformed plate on a suitable tool the knurling 14 is carried out in a conventional manner.

It will be appreciated that the invention results in substantial economy, first because of the saving in the expensive material which is utilized for making the wheels, but especially because the process according to the invention makes it possible to manufacture a large series of wheels on machines operating very rapidly such as transfer presses and cyclically operating tools. The operation of machining the ratchet teeth may moreover, be eliminated and replaced by a simple stamping or shearing step.

While the invention which has been described with respect to a particular embodiment, it will be appreciated that the scope of the invention is not limited to the details of that embodiment. but may be modified as to detail without thereby departing from the basic principles of the invention.

What is claimed is:

l. Abrasive wheel for a cirgarette lighter which comprises a metallic strip provided with integral lateral ratchet teeth on one side thereof and having ends which interfit to hold it in a cylindrical shape, the outer cylindrical surface of said strip being knurled.

2. Wheel as claimed in claim I which comprises a mounting hub force-fitted into said cylindrical plate.

3. Abrasive wheel for a cigarette lighter which comprises a cylinder consisting essentially of an elongated metal strip having integral lateral ratchet teeth on one side thereof and ends having transversely projecting teeth which inter-engage to prevent separation of said ends in a direction which is longitudinal with respect to said strip, the outer cylindrical surface of said strip being knurled.

Claims

1. Abrasive wheel for a cirgarette lighter which comprises a metallic strip provided with integral lateral ratchet teeth on one side thereof and having ends which interfit to hold it in a cylindrical shape, the outer cylindrical surface of said strip being knurled.

2. Wheel as claimed in claim 1 which comprises a mounting hub force-fitted into said cylindrical plate.