FIELD OF THE INVENTION
This invention relates to machines for bending silverware into wearable rings, bracelets and other jewelry.
BACKGROUND OF THE INVENTION
Jewelry such as rings and bracelets can be made by bending spoons, forks, and knives, called “flatware” or “silverware”, and other flat metal workpieces. Devices are available for this bending process, but they have the following disadvantages:
1) Most benders or presses require much strength on the part of the artist to bend silverware that cannot be annealed, such as silver plated steel silverware.
2) Most benders or presses require additional hand tools and a cumbersome process to setup the machine or to change from one style of jewelry-making to another, for example from making rings to making bracelets.
3) Some benders or shaping tools are very heavy and cumbersome to transport, weighing 50 lbs. or more.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in the following description in view of the drawings that show:
FIG. 1 is a perspective view of a jewelry-making press in accordance with aspects of the invention.
FIG. 2 is a perspective view of the press with forming blocks and sleeves removed.
FIG. 3 is a perspective side view of the ram of the press.
FIG. 4 is an exploded perspective view of a first mandrel and ring forming mandrel.
FIG. 5 is a perspective bottom view of a ring-forming block.
FIG. 6 is a left side view of the press showing a ring forming step.
FIG. 7 is a right side view of the press showing a bracelet forming step.
FIG. 8 is a perspective bottom view of a bracelet-forming block.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a press 1 with a horizontal base 4 supporting a structure with a horizontal support arm 6. A ram 8 is mounted in the support arm for vertical motion. It may have a flat side portion 10 for rotational indexing. Two adjustment screws 11A, 11B may be provided in the support arm to tighten against the flat 10 to adjust resistance and rotation angle of the ram. A manual lever 12 or other actuating mechanism turns a horizontal axle 14 in the support arm 6. The axle 14 may extend from both the left and right sides of the support arm and provide a mount 15 on each side for alternate left and right handed use of the lever 12. A rotary-to-linear coupling such as a rack-and-pinion mechanism converts rotation of the axle to vertical linear motion of the ram. The bottom end of the ram may have a soft pad 16 for flattening of spoons or other silverware against a metal portion 18 of the base 4 in preparation for bending. To save weight, the base 4 may be made for example of wood, aluminum, or plastic with a steel plate 18 on top.
A mandrel/receiver 20 is inserted into a lateral through-hole 22 in the ram, and is retained therein by a pin as later shown. The mandrel/receiver supports a selected bracelet forming sleeve 23, 24, 26 that slips over the mandrel/receiver 20 as later shown for pressing silverware against a bracelet forming block 28. A selected second mandrel 30 such as a ring forming mandrel slips into a receiving cavity 32 in the proximal end of the mandrel/receiver 20 as later shown, so that the second mandrel 30 extends laterally from the opposite side of the ram 8 from the mandrel/receiver 20 for pressing silverware against a ring forming block 34. This provides forming blocks 28, 34 on two sides of the ram 8 with pressing tools 20, 30 of two different sizes, allowing a user to quickly switch sides for different parts of a project. The lever 12 can be quickly switched from left to right as later described to make it more convenient to the opposite hand from the workpiece-holding hand. A selection of bracelet forming sleeves 23, 24, 26 and ring mandrels 30 of different diameters are interchangeably mountable in the ram without tools. They may be stored on pins and/or blind holes on the base 4 behind the work area. The mandrels may be elongated cylinders as shown or other shapes, including extrusions of polygons.
A selection of bracelet forming blocks 28 and ring forming blocks 34 of different sizes may be provided. They are quickly interchangeable on the base 4 via vertical pins on the metal plate 18 later shown. Holes 36, 38 in the blocks 28, 34 for these pins are visible. These holes may be through-holes as shown or blind holes in the bottom of the blocks.
FIG. 2 shows the press with the bracelet sleeves and the forming blocks removed showing storage pins 25, 27 for the bracelet sleeves, mounting pins 37, 39 for the bracelet forming block or the ring forming block of FIG. 1. Mounting elements for the lever 12, mandrel/receiver 20, and pins 37, 39 for the forming blocks may be laterally symmetric, so the bracelet and ring forming mandrels and blocks can be placed on either side of the ram per user preference, and for left or right-handed use.
FIG. 3 shows the ram 8 with the flat side portion 10 and the lateral through-hole 22 to mount the mandrel/receiver 20. A pin 40 in the lateral hole retains the mandrel receiver via a twist locking mechanism. The pin 40 is shown centered at the bottom of the lateral hole 22, but it may be centered anywhere around the lateral hole.
FIG. 4 shows a mandrel/receiver 20 comprising a mandrel 20A with a mounting portion 20B that fits closely within the lateral through-hole 22 in the ram 8. Herein, “closely fits” means the mounting portion 20B fits in the hole 22 with clearance that allows manual insertion and removal with minimal play considering manufacturing tolerances and differential thermal expansion during operation. For example a hole 22 with a diameter of 1.0000 inch and a mandrel mounting portion 20B with a diameter of 0.9985 inch works well. In general, a diametric clearance of 0.0010 to 0.0030 inch is suggested. The mounting portion has an axial groove 20C oriented with an axis 42 of the mandrel/receiver. A circumferential groove 20D intersects the axial groove to receive the pin 40 after insertion of the mandrel/receiver into the hole 22 with the axial groove downward, then twisting the mandrel/receiver. The mandrel/receiver is shown rotated 90 degrees clockwise from the insertion position so the axial groove 20C is visible. No flexing parts are needed to aid retention in this twist-lock mechanism because the mandrels 20 and 30 do not tend to twist during use. Friction in the lateral hole 22 prevents twisting of the mandrel when cantilever force on the mandrel is present during jewelry making. The mounting portion 20B has a receiving cavity 32 that receives and mounts a mounting portion 30B of a second mandrel 30 to extend on the opposite side of the ram 8. No axial retention mechanism is needed to retain the second mandrel in the receiving cavity 32. Friction in the receiving cavity during cantilever force on the second mandrel prevents movement of the second mandrel. The assembled configuration is shown in FIG. 1.
FIG. 5 shows a ring forming block 34 with two ring forming channels 34A and 34B of different widths. Two pairs of mounting holes 38A and 38B are used to mount the block onto pairs of pins 37 or 39 on the base of the press. Mounting the block using the two holes 38A aligns channel 34A with a ring forming mandrel in the ram. Mounting the block using the two holes 38B aligns channel 34B with the ring forming mandrel in the ram. The forming blocks may be made of a rigid and tough but semi-soft material such as Delrin® that grips the silverware and does not scratch it. Such material gradually wears over time. To increase the lifetime of the block it may be made at least twice as long L2 as a length L1 (FIG. 3) of the mandrel overlap over the block. This allows the block 34 to be turned 180 degrees to present a new wear surface in each channel, doubling its wear lifetime.
FIG. 6 shows a left side view of the press 1 with a workpiece 42 being bent between a ring-forming mandrel 30 and a ring-forming channel 34A in a forming block 34. The workpiece may be silverware such as a metal spoon, knife, or fork. It may first be flattened between the pad 16 (FIG. 1) on the bottom of the ram 8 and the metal plate 18 in the base 4 before performing the bending operation shown.
FIG. 7 shows a right side view of the press with a workpiece 44 being bent between a bracelet-forming sleeve 26 on a mandrel 20 and a channel 28A in a bracelet-forming block 28. The lever 12 may be retained in a hole through the axle 14 by a quickly releasable device such as a cotter pin or a hairpin clip 45. The lever can be quickly moved from the right side of the arm 6 as shown to the left side for use by a user's left hand on the lever with the right hand holding the workpiece 44 between the mandrel 20 and forming block 28 on the right side. A selection of ring mandrels 46, 48 of different sizes may be stored in blind holes in the base 4 for quick selection, mounting, and interchanging in the ram 8. Each ring mandrel has the same diameter base 46B for insertion into the receiving cavity 32 of the mandrel/receiver 20 as shown in FIG. 4. A blind hole or a pin 50 may be provided to store the mandrel/receiver 20 on the base.
FIG. 8 is a perspective view of a bracelet-forming block 28 with a channel 28A in the top surface of the block, and two holes 36 in the bottom of the block for mounting the block on the mounting pins 37 of FIG. 2.
The present jewelry-making press can be quickly configured and reconfigured without tools for making ring-shaped jewelry of different diameters from silverware or other flat workpieces. It provides mandrels and respective forming blocks on two sides of the ram and a lever that is quickly switchable to left-handed or right-handed operation for high productivity. It can be provided as a complete self-contained manually operated press with high mechanical advantage weighing less than 15 lbs. including a selection of forming blocks and mandrels of different sizes.
While various embodiments of the present invention have been shown and described herein, such embodiments are provided by way of example only. Variations, changes and substitutions may be made without departing from the invention herein.
Patent Grant
10272484
