US1741302A - Means for clamping die blocks - Google Patents

Description

Dec. 31, 1929. c. A. HUDSON MEANS FOR CLAMPING DIE BLOCKS 'Fi led March 18, 1929 3 the ends of the block.

Patented Dec. 31, 1929 UNITE STATES CHAR-LES A. HUDSON, or ELLISBURG,

NEW YORK, ASSIGNOR TO F. E. HUDSON & SONS,

INCORPORATED, OF ELLISBURG, NEW YORK, A CORPORATION OF NEW YORK MEANS FOR CLAMPING DIE BLOCKS Application filed March 18, 1929. Serial No. 347,932.

This invention relates to built-up Wooden die-blocks, designed for use in connection with clicking machines, and the like, for cutting leather and other sheet materials, and has 5 for its object to provide a block composed of a number of similar segments whose abutting sides are usually glued to each other, and wherein the joints and grain of the wood extend from top to bottom of the block.

These composite blocks are invariably bound by external iron straps or bars, which are mounted in a common plane upon the upright sides and ends, and are held in place and given suitable tension by bolts or equivalent adjustable means. According to common practice, these clamping irons extend respectively the full length of the sides and ends, and interlock or otherwise join each other only at. the four corners of the block, and

when the bolts are drawn tight, the irons exert their greatest pressure at the corners, while their medial portions tend to flex and bow outwardly, thereby failing to equally reinforce all parts of the bloc This trouble has been remedied to some extent, by the more or less expensive and complicating expedient, of perforating the blocks transversely at frequent intervals, and then passing threaded rods through the perforations and the longer irons,

to which nuts are applied for drawing the i irons tightly against the opposing side edges of the block. This still leaves the block without means for adequately clamping the medial portions of the transverse irons against Hence, when the block is subjected to severe stresses and shocks incidental to the operation of a die-press, the

ends of the block tend to split, and being with- 1 out effective means for holding the split por- 40 tions in place, the blocks must be discarded,

or else rebuilt and reconditioned.

A particular object of the present invention is to eliminate the straight full-length side and end clamping irons, and to substitute therefor four angular irons of substantially the same size and shape, and therefore interchangeable. These irons preferably conform to the angularity of the four corners of the block, and are so proportioned that the free ends of their arms may be disposed at or near the longitudinal and transverse centers of the block, whether the blocks are square or oblong, the said ends being formed with outwardly projecting lugs, which are perforated to re ceive bolts or other couplings by which acontinuous bond is effected. By disposing the coupling means midway of the length and breadth, instead of at the corners, of the block, the tightening of the four bolts draws the irons against the sides and ends, without danger of the irons flexing or bowing outwardly away from the medial portions of the block. The angular irons are all formed to a common template, and each iron may be applied to either of the four corners of the block without requiring any alteration or readjustment. Ordinarily, the transverse reinforcing rods may be dispensed with, but a smaller number of such rods may be employed on the longer blocks, to supplement the side arms of the irons and increase the factor of safety.

The various features and parts of the invention will be understood from thedetailed description which follows, and by reference to the accompanying drawings, in which- Figure 1 is a top plan View of the sectional rectangular die-block, showing'its top portion tapered; also showing similar right-angle clamping irons embracing its four corners. Fig. 2 is a side elevation of the same. Fig. 3 is a side elevation of a plain unbeveled block, showing the angle irons disposed midway of the height of the block. And Fig. 4 is a broken top plan View of the tapered block, showing tension means interposed between the spaced clamping lugs at the sides and ends of the block.

In the'drawings, 2 represents the built-up die-block, which comprises a number of transversely disposed wooden segments 2, the latter being of uniform height and carefully jointed and glued together, to form a solid rectangular or square body, whose top corners at the sides and ends are preferably beveled, as shown in Figs. 1 and 2, to provide a cutting surface of substantially less area than the bottom of the block, primarily to prevent the dies from chipping said corners and impairing the block.

In practically all built-up wooden dieblocks of the character described, the gluing of the segments 2 does not effect a bonding that is powerful enough to withstand the hard blows and high pressure of the dies during the cutting operations, and it has been the common practice to supplement such adhesive bonding by mounting metal bars or straps on the upright sides and ends of the blocks. Peretofore, these bonding irons have usually been straight, and slightly longer than the side and end dimensions of the blocks, the ends of said bars being formed or fitted with screw threaded or other interlocking means, by which the retaining and clamping may be effected. As a general rule, die-blocks of this class have been formed with square-cut top and bottom corners, and the clamping irons have been usually disposed midway of the height of the blocks, as shown in Fig. 3, and when the blocks are redressed after having been worn uneven by continuous cutting, these irons have either to be adjusted downwardly, in order to facilitate repeated redressing of the'upper face, or else the blocks are inverted and alternately worn and redressed until further conditioning is hindered by the proxim ity of the irons. WVhere the old straight irons are employed, the tightening of the bolts effect the greatest clamping pressure at or adjacent the corners of the block, and the medial portions of the irons tend to spring away from the sides and ends ofthe'block, which leaves the longitudinal and transverse centers thereof unprotected and liable to crack or split, when the blocks aresubjected to the stresses and shocks produced by the dies.

In the present case, angular irons, as 3, are substituted for the straight clamping members, each of said irons having one long arm and a short arm '(in case the blockis oblong), as 3 and 3, which respectively engage the sides and ends of the block. These irons are formed to a common pattern or template, whose angularity conformsexactly to that of the four corners, as 2 of the block, and the irons 3 being alike in all their parts, may be interchangeably applied to the several corners 2. The free ends ofthe arms 33 aresimilarly bent outwardly to form lugs 3 the latter beingperforated to receive bolts 4, by which the corresponding arms of adjacent irons may be adjustably connected and drawn towards each other, for tightly clamping the irons tothe sides and ends of the block, as shown. Thelngs 3" are suitably spaced for affording ample range of adjustment, as well as to provide in a simple manner for readily and securely clamping the block to the bed of the die-press. The bolts 4 are preferably threaded at both ends to receive nuts 5, by which the clamping and adjusting may be rendered more effective. The bolts 4 are normally spaced from the block, and when the nuts 5 are tightened up, the lugs spring slightly towards each other.

plained.

This tends to increase the clamping pressure intermediate the corners 2 and prevents the irons from springing away from the block, as in the case of the straight irons, as eX- This exertion of relatively great pressure midway of the length and breadth of the block, renders it unnecessary to provide the usual transverse reinforcing rods, except onlyin case of blocks of extraordinary length, when rods, as 6, may be employed for reinforcing the longer arms of the irons 3, as shown in Figs. 1 and 2.

Fig. 3 shows the block 2* mounted upon and secur d to the bed 7 of a die-press, bv a plurality of similar adjustable clamps, each comprising a member 8, which is pivoted to the bed by a bolt 8, and a member 9, which is formed with a hook 9 that grips one of the bolts 4:, and is provided with a lug'9 having a'perforation that receives a threaded portion 8 of member 8, to which a nut 8 may be applied for effectingthe clamping.

In Fig. 41, stiff springs 10 are mounted upon the bolts between one of the lugs 8 and the adjacent nut 5, to offer resilient resistance to the loosening of the nuts, but more,particularly to compensate for the usual expansion and contraction of the block, due to changes of weather and other conditions. Bythe provision of the springs l0,'the great strains exerted by the expanding of the segments will be absorbed by the springs, and in case of contraction of the block, the relatively great tension of the springs when the nuts are properly tightened will hold the segments from separating or splitting, without necessitating any additional adjustment of the clamping means.

Having thus described my invention, what e I claim is 1. In combination, a rectangular built-up die-block, a plurality of similar clamping irons, each iron being bent to conform to the angles of the corners of the block, the 7 arms of said irons terminating respectively near the longitudinal and transverse centers of the block and their free ends being formed with perforated lugs that .register with the lugsof the adjacent irons, and means coacting with the registering lugs for clamping said irons against thesides and ends of the block.

2. The combination with a segmental wooden die-block, of a plurality of clamping irons adapted to be interchange-ably.mounted upon-the four corners of the block, said irons being conformed tothe angles of said corners, the arms of each iron adapted to-overlie a portion of one sideand one end of theblock, the free ends of said arms being formed with perforated lugs, the lugs of the adjacent irons at the opposite sides and ends being spaced apart, and bolts piercin each pair of lugs for drawing'the irons tightly against the corners and the intermediate portions of said sides and ends.

8. The combination With a rectangular dieblock, of a plurality of L-shaped clamping irons adapted to be mounted in a common plane upon the upright sides and ends of the block, each of said irons being formed with one long and one short arm adapted to partially overlie respectively one side and one end of the block, the free ends of the arms being bent outwardly and perforated, the corresponding perforated ends of the adjacent irons being juxtaposited at the longitudinal and transverse centers of the block and screw-threaded means for adjustably connesting said perforated ends and for clamping the irons throughout the length and breadth of the block.

In testimony whereof I afiix my signature.

CHARLES A. HUDSON.

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