Improvements in or relating to Adjustment Devices for Spring Power Hammers and similar Machines.
Year: 1898

page_text: Date of Application, 22nd Jan., 1898-Accepted, 12th Mar., 1898
Improvements in or relating to Adjustment Devices for Spring
Power Hammers and similar Machines.
I, PER HOLMBERG, of Ljusne, in the Kingdom of Sweden, Iron Turner, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to an arrangement by means of which the length of the
stroke of spring power hammers and similar machines can be easily adjusted while
the machine is running.
Fig. 1 shows a hammer of this kind, viewed from one side and partly in section,
and Fig. 2 shows a transverse section of the same. Fig. 3 shows a.modification.
The machine is composed, as usual, of a frame a and anvil b, a hammer head c, a
lever d to which the hammer head is attached by means of the spring e, and a crank-
shaft facting on the lever. In the plane of the lever d there is journalled in
the frame aa ring g of comparatively large diameter through which ring the
crank-shaft f passes. To the ring is connected an arm h which arm is connected to the
crank of the shaft f, it being provided with a slot k in which reciprocates during
the rotation of the crank a journal-box or sliding-block embracing or connected to
the crank. The arm h which is by this means given an oscillating movement is,
finally connected to the lever d by means of links m or the like. The length of the
stroke is adjusted by revolving the ring. If the ring be rotated toward the right,
Fig. 1 the angle formed between the arm and the perpendicular through the shaft
f will be decreased. The stroke of the arm h and consequently that of the lever and
the hammer head will thus be smaller. When rotating the ring toward the left the
angle will increase and the stroke of the arm and the hammer head will be greater.
For revolving the said ring various arrangements may be employed. In the drawing
the ring is provided with teeth with which engage two pins n that act as a pinion,
the pins being attached to a common centre-piece the shaft o of which is provided
with a crank-handle p. An additional advantage of the construction described is
that the hammer head ascends slowly and descends quickly as the crank at the
rotation of the shaft f in the direction of the arrow (Fig. 1) acts on the outer part of
the arm h, when the hammer head ascends, but on the inner part of the arm, when
the hammer head descends. In order to allow of raising and lowering the hammer
head to suit different thicknesses of the work the rear end of the lever d is attached
to a worm-wheel sector 7 mounted on the frame and engaging with a worm 8. By
turning a handle attached to the latter the end of the lever may be raised or
lowered.
The construction described may be so modified that instead of the ring g a crank
may be used for moving the fulcrum of the arm h. This arrangement is shown on a
smaller scale in Fig. 3. h¹ indicates the fulcrum of the arm. On the shaft f is
carried the crank h² from which the.arm h issues in the same manner as from the
ring. If the crank h² be rotated,-the said crank for this purpose being provided with
a special crank h³, or a hand-wheel or the like,-the fulcrum of the arm will evidently
be moved in the same manner as by means of the ring. The crank h² remains