US514787A - Power-hammer - Google Patents

Description

UNITED STATES PATENT OFFICE.

JAMES BERNARD SWEENEY AND ROBERT WALLACE LAIRD, OF ST. JOHNSBURY, VERMONT.

Powl-:R-HAMMER.

SPECIFICATION forming part of Letters Patent No. 514,787, dated February 13,1894.

Application filed May l, 1893. Serial 110.472,538. (No model.)

' SWEENEY and ROBERT WALLACE LAIRD, both of St. Jo'hnsbury, in the county of Caledonia and State of Vermont, have invented a newv and Improved Power-Hammer, of which Athe following is a full, clear, and exact description.

Our invention relates to improvements in power hammers; and the object of our invention is to produce an extremely simple and inexpensive hammer, which is adapted to deliver an elastic blowsimilar to that given with a hand hammer, which is provided with a well balanced tilting belve to actuatethe hammer,

and which has a simple means of adj usting the hammer so as to regulate its stroke.

To these ends our invention consists of certain features of construction and combinations of parts, as will be hereinafter described and claimed. f

Reference is to be had tothe accompanying drawings forming a part of this specification, in which similar figures of reference indicate corresponding parts in all the views.

Figure 1 is a side elevation of the machine embodying our invention, with a part of the helve broken away. Fig. 2 is a broken front View of the machine. Fig. 3 is a sectional plan view of the same; and Fig. 4 is a horizontal section on vthe line 4-4 of Fig. 1.

The machine is provided with a suitable frame 10, which has a thickened table 11 at its'front end, in which is dovetailed the anvil 12 which may be of any suitable construction, and above this anvil is a vertically reciprocating hammer 13 which is carried bythe head 14, being dovetailed therein, as shown in Fig. 1, and the head is held-to slide up and down on the front lof the frame andin slideways 15, the head being preferably provided with flanges 16 which Lenter the slideways. The head 14 is hollow at its upper end to fa-v cilitate its connection with the tilting helve 17 which actuates the hammer head and hammer, this helve being carried by a transverse shaft 18 inthe upper part of the machine frame, and at its rear end the helve is provided with a suitable adjustable counterbalance 19 which enables the helve to be prop erly balanced and easily moved. The helve 17 is split at its forward end and vthe walls of the split portion liare vertically, as shown by dotted lines 2O in Fig. 1, and in this split portion of the helve is held a strong dat spring 2l, this being fastened in place by a'bolt 22 or equivalent fastening, and the Haring shape of the split end of the helve enables thev spring to bend easily over the walls of the split or slot without excessive strain. The frontend of the spring 21 projectsrinto the head 14 and is held in a'box 23 which has trunnions 24 pivoted in boxes 25, these being held to slide inl horizontal slots 26 in the sides of the head 14, and a connection is thus formed between the spring and the head, which causes the spring when sprung, t0 move the head vertically and which permits sufficient freedom of movement to avoid friction.

The shaft 18 is driven bya suitable pulley 1Sa or equivalent driving gear, and it carries an eccentric 27 which actuates a depending rod 28, see Figs. 1 and 3, and moves the rod up and down. The eccentric rod 28 is pivoted at its lower end to atiltinglever 29 which is held in a nearly vertical position and is fulcrumed on a stud 30 which is journaled in boxes 3()a which are adapted to slide in the curved slot 32 of the main frame 10, as shown in Fig. 1. The slot 32 describes an arc of a circle, whose center is the shaft 18, so that the boxes 30a4 may be readily adjusted in it. The stud 30 is screw threaded and provided at its outer end with a wheel nut 31, and as the central portion of the lever 29 bears against the inner box 30a, it will be seen that by tightening the wheel nut, the boxes may be clamped firmly to the frame and the position of the stud 30 fixed. The object of this arrangement is to provide for easily adjusting the hammer to metals of different thicknesses.

-It will be seen that by loosening the wheel nut 31, the boxes 30a may be pushed forward in the slot 32, so as to swing forward the rod 28, thus tilting the shaft 18 and helve 17 and raising the hammer head. The boxes may then be fastened in place as described, and it will be seen that the position of the hammer head may thus be very nicely adjusted.

The rear end of the lever 29 is pivoted to a pitman 33 which extends upward, and this IOO connects at its upper end with a bolt 34. which projects through a longitudinal slot in the rear end of the helve 17, and the bolt is provided at one end with a wheel nut 36 by which the bolt may be fastened in a desired position, the arrangement being like that described above for fastening the stud 30; and by this means the upper endof the pitman 33 maybe adjusted and fastened atany point in the slot 35 so as to bring it the right distance from the pivot of the helve 17 to give the proper stroke to the helve and the hammer with which the helve is connected.

It will readily be understood that the adjustment of the stud 30 in the direction of the anvil, for instance, will necessarily draw downward on the pitman, which will raise the front end of the helve and with it the hammer, and thus the movement of the hammer will be within higher points than before, to accommodate thicker metal on the anvil.

The machine is operated by setting the shaft 18 in motion and when this is done, the eccentric 27 moves thepitman 28 up and down, thus tilting the lever 29 and actuating the helve 17 by the pitman 33 which connects the helve with the lever 29. The swinging movement of the helve causes the head 14 to be moved up and down and the spring connection between the head and the helve causes the hammer, on its descent, to deliver an elastic blow, as the spring has a freedom of move` ment corresponding very much to the swinging of a persons arm.

Having thus described our invention, We claim as new and desire to secure by Letters Patent- 1. A power hammer, comprising a tilting helve having a split end, a reciprocating hammer arranged opposite the split end of the helve, a spring held in the split end of the helve and projecting into the hammer head, and a box to receive the spring, the box being pivoted in the hammer head and held to slide horizontally therein, substantially as described.

2. A power hammer, comprising a vertically reciprocating hammer, a tilting helve having one end elastically connected with the hammer to drive the same, a revoluble driving shaft forming the fulcrnm of the helve, a tilting lever arranged parallel with the helve and having an adjustable fulcrum, mechanism for tilting the lever by the movement of the driving shaft, and an adjustable connection between one end of the lever and the helve, substantially as described.

3. A power hammer, comprisinga supporting frame having a revoluble driving shaft in its upper portion, an anvil carried at the frontend of the frame, a helve pivoted on the driving shaft, a vertically reciprocating hammer head, a flexible connection between the hammer head and helve whereby the tilting of the helve will move the hammer head, a tilting lever pivoted in a horizontally adjustable bearing beneath the helve, an eccentric and rod connection between the driving shaft and one end of the tilting lever, and a pitman connecting the opposite end of the lever to the helve and adjustable longitudinally on the latter, substantially as described.

4. A power hammer having its helve fulcrnmed intermediate of its length, a power shaft, an eccentric on the shaft, a rocking arm having connection at one end with said eccentric, a pitman connected with the opposite end of the rocking arm, and with the helve at a point on the latter beyond its fulcrum, and an adjustable fulcruin for said rocking arm, substantially as described.

JAMES BERNARD SWEENEY. ROBERT WALLACE LAIRD. Witnesses:

O. A. GROW, A. B. PRINGLE, JOHN R. WHITNEY.

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