GB2111914A

GB2111914A - Engraving device

Info

Publication number: GB2111914A
Application number: GB08235593A
Authority: GB
Inventors: Lago Gianluigi Dal
Original assignee: Faimond Di Dal Lago Gianluigi
Current assignee: Faimond Di Dal Lago Gianluigi
Priority date: 1981-12-18
Filing date: 1982-12-14
Publication date: 1983-07-13
Also published as: GB2111914B; FR2518460B3; IT8163387V0; FR2518460A1; DE8235125U1; ES269230Y; CH654774A5; ES269230U

Abstract

An engraving device for continuous ornamentally machining chains (27), bracelets or the like and which is connectable to the spindle of a stone- cutting machine comprises a rigid framework (2) and a displaceable framework (22) slidably mounted thereon so as to be oscillatable, a ring nut (5) attachable to the fixed housing and connectable to the spindle of the machine, and a swivel type milling cylinder (4) mounted on a shaft passing through the ring nut. The milling cylinder (4) carries an engraving tool. The ring nut (5) and milling cylinder are rotatable. The engraving tool contacts the workpiece (27) and is controlled by means of a tracer point (31) fitted to the rigid framework (2) of the machine cooperating with a cam (28) attached to the displaceable framework (22), the displacement of the framework (22) on the rigid framework being effected by means of lateral slides. <IMAGE>

Description

SPECIFICATION Engraving device The present invention relates to an engraving device suitable for ornamental machining of chains, bracelets and/or similar objects in a continuous manner and which is capable of being fitted to the spindle of a conventional stone-cutting machine.

To effect ornamental machining of articles, the usual practise is to mount an engraving tool on the framework of a stone-cutting machine. The machining is generally carried out by means of a diamond cutting head which traces a faint preliminary incision. For more complex machining operations, for example, to form a tracing in the form of a star, a number of lines, intersecting at various angles, must be produced. This can generally be achieved only by adjusting the cutting angle manually, usually by adjusting a chain-bearing clamp and the cutting head. The device is usually chain-fed and such chain feed must be arrested each time an adjustment is made. Such a machining process is liable to cause errors in the machining, continuous accurate machining cannot be achieved, much time is wasted in such a process and the production costs are high.

The present invention seeks to provide a device in which the above-mentioned disadvantages are substantially eliminated, the device permitting chains, bracelets and similar objects to be ornamentally machined continuously and automatically.

According to the present invention, there is provided an engraving device for continuously ornamentally machining chains or the like and which is connectable to the spindle of a stone-cutting machine comprising a rigid framework and a displaceable framework slidably mounted thereon so as to be oscillatable, a ring nut attachable to the fixed housing and connectable to the spindle of the machine, and a swivel type milling cylinder, the milling cylinder being mounted on a shaft passing through the ring nut; the milling cylinder carrying an engraving tool, the ring nut and milling cylinder being rotatable; the engraving tool contacting the workpiece by means of a tracer point fitted to the rigid framework of the machine by means of a cam attached to the displaceable framework, the displacement of the framework on the rigid framework being effected by means of lateral slides.

The invention will be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a schematic elevational view of a device in accordance with the present invention; Figure 2 is a view similar to Figure 1 but showing the device in a position of use; Figure 3 is a schematic view of a cam forming part of the device shown in Figures 1 and 2; Figure 4 is an exploded perspective view of a milling cylinder and crown gear ring nut forming part of the device shown in Figures 1 and 2; Figure 5 is a perspective view, partly broken away, of the milling cylinder and ring nut assembly shoswn in Figure 4; Figure 6 is a schematic underneath plan view of the milling cylinder shown in Figures 4 and 5, and Figure 7 is a schematic view of a chain after ornamental machining has been effected thereon.

In the drawings, reference numeral 1 denotes, generally, a stone-cutting machine. Such machine comprises a rigid framework 2 having a projecting upper portion 3. Attached to the lower end of the portion 3 by means of a vertical axle is a milling device 4.

The milling device 4 comprises ring nut 5 mounted on a shaft 6 mounted on the framework, and a cylinder 7. The device 4 is rotated by a shaft (not shown) which passes through both the shaft 6 and the ring nuts. In its lower region the ring nut 5 includes a crown gear 8 which is attached to a drive belt 9 and which involves other rotational devices described hereinafter.

The cylinder 7 receives in its upper end the lower end 8 of the ring nut Son a seat 10. In its lower region, the cylinder receives a horizontally adjustable tool clamp 12 on a seat 11.Ashaft 13 passes through the tool clamp 12. On its inner end, the shaft 13 carries a roller 14 fitted with a diamond cutting head 15. On its outer end, the shaft 13 carries a gear 16 projecting onto the lateral surface of the cylinder 7 at a seat 17.

Above the seat 17 on the cylinder 7, transmission gears 19 and 20 are fixed on a seat 21. These transmission gears 19 and 20 occupy part of the interior space of the cylinder 10. The crown gear 8 and the rollers 16, 19 and 20 are interconnected by a gear belt which permits the rotation of the shaft 13 attached to roller 14.

A further framework 22 is mounted below the milling device 4 on an axle extending at right-angles to the milling device 4. This member 22 comprises a rigid portion 23 oscillatably mounted on the framework 2 by means of vertical slides (not shown), and a rotating shaft 24 which is driven by a conventional motor 25, the shaft being connected to an adjustable clamp 26 bearing the chain 27 to be machined.

The oscillating portion is maintained constantly under tension by means of springs and/or other devices (not shown), and includes a cam 28, the notches 29 of which have, as shown in Figure 3, an angular profile which is equal to, or less than, the angle of the stone cutter.

The cam 28 is driven by the motor 25, by means of a transmission belt 30, and is connected to a tracer point 31 fixed to the framework 2.

One chain machining stage will now be described.

One end of the chain, in a coiled form, is positioned on the clamp 26. The actuation of the drive devices causes the milling cylinder 7 to rotate. Such rotation of the cylinder 7 drives the roller 16, and hence the engraving device in the form of a cutting head 15 through the intermediary of the belt 9. In this particular example, the gear ratio between the crown gear 8 and the engraving device 15 is 1:3, that is to say, one rotation of the milling cylinder 7 will entrain three rotations of the cutting head. Simultaneously, the motor 25 drives the oscillating framework 22 causing the clamp 27 and the cam 28 to rotate. When the tracer point 31 penetrates one of the notches 29 of the cam, the entire oscillating portion rises until the chain carried by the clamp 26 is brought into contact with the engraving portion of the milling device 4.The engraving device will make three engravings at different angulations during one full rotation of the cylinder 7, thus producing a starshaped diamond pattern (see Figure 7). As its rotation continues, the cam 28, once again by means of the tracer point 31 projecting from the indented section, causes the oscillating device to travel to the farthest end of the engraving device.

One advantage of such a system is that the engraving angle of the engraving device 15 can be varied relative to the chain or workpiece by means of the locking and clamping devices to the spindle 6 of the ring nut 5.

Furthermore suitable horizontal adjusting devices are provided to allow the block 12 to slide into the seat 11, thereby displacing the engraving device 15 from the cylinder axes so as to obtain a different type of work.

Finally, it is possible to adjust the oscillating portion 22 by replacing the cam 28 shown in the drawings by a cam of a different form or by modifying the gear ratio between the cam and the driving devices.

In the above example, the clamp-carrying element portion is oscillatable. However, the machine can also be utilised if the engraving tool oscillates.

Claims

1. An engraving device for continuously ornamentally machining chains or the like and which is connectable to the spindle of a stone-cutting machine comprising a rigid framework and a displaceable framework slidably mounted thereon so as to be oscillatable, a ring nut attachable to the fixed housing and connectable to the spindle of the machine, and a swivel type milling cylinder, the milling cylinder being mounted on a shaft passing through the ring nut; the milling cylinder carrying an engarving tool; the ring nut and milling cylinder being rotatable; the engraving tool contacting the workpiece by means of a tracer point fitted to the rigid framework of the machine by means of a cam attached to the displaceable framework, the displacement of the framework on the rigid famework being effected by means of lateral slides.

2. An engraving device as claimed in claim 1 wherein the device which causes the rotation of the cylinder comprises a shaft extending through the spindle and ring nut and driven by a motor.

3. An engraving device as claimed in claim 1 wherein the device which causes the rotation of the cylinder comprises a toothed chain driven by a cam passing through the ring nut by means of transmission gearto a ratchet roller which, in turn drives an engraving tool arbor.

4. An engraving tool as claimed in any preceding claim wherein the cam has splines having an angulation equal to or less than the angulation of the cutting tool.

5. An engraving tool as claimed in any preceding claim in which more than one engraving tool is provided.

6. An engraving tool as claimed in claim 1 constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.