Stamp′ing-press.
Another name for the stamp-ing-machine (which see also).
Machinery for making seamless articles from sheet-metal by stamping was devised in
France as early as 1840.
The first attempts, which were partially successful, were made with the droppress.
This, however, it was thought, did not allow sufficient time for the metal to assume the required form without tearing, and the screw-press was substituted for it giving better results.
The cam-press has also been generally used in
France, which has long maintained a pre-eminence in wares of this kind.
Vessels are manufactured from
sheet-iron, the depth being given at several successive pressings, depending on the depth of the article.
The metal is annealed after each pressing, and is finally turned.
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Machine for stamping forks, spoons, etc. |
Such articles are now manufactured in this country from tinplate, annealing being dispensed with, and the goods are prepared ready for market without re-dipping.
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Stamping-machine (shoe machinery manufacturing Co.). |
Fig. 5543 illustrates a machine for forming pans or kettles from blanks.
There are several molds for each pan, the operation being a progressive one; deeper and deeper molds being used successively so as to stretch the blank more and more, to avoid the tearing which would result from the attempt to stretch the thin sheet-metal at a single impulse, even though very moderately and gradually performed.
The hollow mold is placed on the flat table, shown in the view, and upon it is laid a blank of sheet-metal, or a pile of blanks when several are to be stamped at once.
The under side of the blank rests upon the flat upper surface of the hollow die, and the holder (shown with a round opening through it) is brought down upon the blank so firmly that, when the upper die descends, the metal has to expand into the hollow die, stretching out into a smooth seamless pan or kettle, without buckling or corrugating the margin.
The upper
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or salient die is fastened to the headed screw (which is shown above), and is operated when the cross-head descends by means of the pitmen and cranks on the sides of the machine, forcing the blanks into the hollow die as far as the ductility of the metal will permit.
The holder is clamped down upon the blanks by means of cams beneath the table.
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Howard's stamping-press for sheet-metal ware. |
Metallie cartridge-cases are made in the same way.
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Grimshaw's machine for shaping sheet-metal. |
Fig. 5544 is a machine for shaping sheet-metal.
The plate to be shaped or stamped is placed upon the die, and the attendant depresses the treadle connected with the valve-rod of the chest
c, whereupon, the water being admitted above the pistons of the four cylinders, the clamp
b is forced downward and fastens the circumferential portion of the plate between its own lower surface and the flat upper surface around the die. The other treadle is then depressed, and causes the central piston to descend and force the follower or stamp downward, so that the sheet-metal is pressed into the die and made to receive a corresponding form.
As the sheet-metal is thus forced into the die by the pressure of the follower or stamp, its circumferential portions are drawn out from under the clamp, and the strain or tension thus exerted upon the metal effectually insures smoothness in the completed article, and also enables a deeper dish or similar piece of ware to be produced at a single operation.
a is a casting with four cylinders, and
e the top plate on which the receiving-chests are placed.
The press (
Fig. 5545) for stamping hollow articles for sheet metal has a cross-head
a reciprocated by connecting-rods from crank-arms on a horizontal shaft rotated by gearing driven from the fast-pulley
b. The cross-head receives a convex die
c, which works into a counterpart concave die held by the table
d, which is suspended by a yoke and rod from a piston in the cylinder above.
The latter has a cushion of air in its lower part, so as to give a certain degree of elasticity to the blow, the table and lower die receding slightly before the pressure of the upper die.
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Stamping-press for hollow ware. |
Debeauvais' press (
Fig. 5546) is operated by two frictionwheels
a a′ attached to opposite ends of a shaft
b, rotated by a belt turning the pulley
c. When it is desired to depress the platen or stamp, the shaft
b is, by means of a treadle operating a connecting-rod
d, thrown to the left, bringing the face of the wheel
a in contact with the periphery of the horizontal wheel
e keyed on the head of the screw.
On releasing the treadle a spring, which throws the shaft
b to the right, is permitted to act bringing the wheel
a′ in contact with
e and causing a reverse movement of it and the screw, lifting the platen until the cone
f at top of the screw strikes a cone
g on the shaft
b, throwing the two wheels out of contact.
The rapidity of movement of the platen progressively increases, as the wheel
c recedes from the centers of the wheels
a a′ either in the ascending or descending movement of the screw.
Fig. 5547 is for striking ornaments on metal or leather, or for cutting disks or planchets from sheet-metal.
The punch or upper die is brought down by pressure of the foot on the treadle, the plunger being actuated by a lever which is vibrated by toggle motion set in operation by the treadle The lower and upper dies bear the relation required by the work, whether for mere impression of a raised ornament or the severance of pieces of metal.
Fig. 5548 is a stamping-press for cutting wads, washers, or planchets from sheet-metal strips.
A swivel-step is seated in the annular base and a swivel diechuck connected with the lower end of the slide, or to the stem thereof.
A spring-dog is applied to the chuck by means of a screw to engage with the stem of the slide, the hook end entering a socket made in each side of the stem to prevent the slide
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from turning when set for operation.
A similar dog holds the swivel-step.
See also coining-press.
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Stamping-press. |
Fig. 5549 is a fly-press for stamping monograms on
letter-paper and envelopes: also, by change of dies, for embossing paper, leather, or other materials.
The plunger is depressed by the revolution of the fly and returned by the spring.
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Stamping-press for ornaments and jewelry. |
