Improvements in Pneumatic Hammers.
Year: 1896

page_text: COMPLETE SPECIFICATION.
Improvements in Pneumatic Hammers.
I, MELVIN ALBERT YEAKLEY, of 758 Clair Street, Cleveland, Ohio, United
States of America, Gentleman, 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:-
My invention relates to pneumatic hammers, and the invention consists in the
construction, combination and arrangement of parts, substantially as shown and
described and particularly pointed out in the claims.
In the accompanying drawings
Fig. 1 is a side elevation of the hammer.
Fig. 2 is a vertical central sectional elevation of the hammer.
Fig. 3 is a vertical central sectional elevation of the air compression or power
cylinder and piston and the power connections on a line corresponding to 3, 3,
Figs. 2 and 4.
Fig. 4 is a plan view of the hammer.
Fig. 5 is an enlarged vertical central sectional elevation of the upper part of the
hammer, corresponding to the upper portion of Fig. 2, but divested of the pistons and
some other parts shown in said figure.
Fig. 6 is a horizontal sectional plan view looking downward from a line corre-
sponding to 6, 6, Fig. 5.
Fig. 7 is a detail in perspective of the valve which controls the inlet to the hammer
cylinder.
Fig. 8 shows the sleeve by which said valve is actuated.
Fig. 9 is a perspective view of a double hammer in which the same general
principles of construction are present as in the foregoing figures.
Fig. 10 is a horizontal sectional plan view of Fig. 9, on the lines substantially of
the valves therein at the top.
In this body or frame A are formed two piston chambers 2 and 3 of which
chamber 2 at the rear is the power cylinder or chamber, and chamber 3 at the front
and top is the hammer piston chamber. Chamber 3 in this instance, Fig. 6, is
rectangular in cross section, while chamber 2 is circular in cross section. These
chambers are shown here as in parallel lines but they may be in divergent lines as
well, especially chamber 2 in respect to chamber 3.
I have preferably divided chamber 3 vertically into two equal parts, half of which
is formed by the body A and the other half by the separate part 4. This part 4 is
secured by rods 5, a suitable packing being interposed between said parts to make a
perfectly air tight joint.
This sectional construction of the chamber makes the chamber accessible at any
time for repairs or any other purpose, and provides for taking up wear by the piston.
Said chamber 3 has a cap B, with an inwardly projecting hollow portion 8 at its
center, which allows the piston the full stroke of the chamber without obstruction
and practically eliminates a large dead space.
The power or air compressing piston Coperates in the cylinder or chamber 2.
The piston C is actuated from the fly wheels D, D', two being preferably used, and
is connected therewith by rod 4'. The wheels D, Di, are in turn actuated by a band
wheel E or other suitable power connection. In this instance said wheel E is on the
same shaft as wheel D, but wheel D' is supported on its own short shaft E', and
rod 4' connects said wheel with the piston C. When the hammer is at work the
piston C is kept constantly and regularly in movement.

page_text: The hammer piston or head F has the hammer or upper die G fixed thereto.
Beneath the said hammer is arranged the lower die H, resting upon a die block H'
which itself is supported upon the body A.
The several parts G, H, and H' are separable and the piston F is packed to avoid
leakage. It will be noticed that the piston F has no rod or other operating
connections, and that it is wholly an atmospheric actuated piston, governed exclusively
by the atmosphere in all its movements.
Now, in order that the atmospheric pressure and exhausts produced by the air
compressing piston C, may be felt and utilized in the machine, it is necessary that
there should be certain intervening mechanism between the power producing
chamber 2 and the power utilizing chamber 3. To this end, I have provided an air
channel directly from the upper portion of chamber 2 to the chamber 8, and in said
channel are interposed suitable valves to control and regulate the flow of air back and
forth, as will now appear. The through passage referred to is indicated by 10 and 12,
sections of the same passage, and having a valve chamber 11 between them. In
this valve chamber are located two rotating valves K and L, respectively, and
beneath valve chamber 11, and opening into the same is a chambered pocket or
well, 13. This well serves as a contraction and expansion chamber for the
atmosphere, and as a sort of reservoir. The valve K controls the flow of the air out
the power side of the valve chamber, and the valve L controls the flow of the air on
the hammer side of the valve chamber and the hammer chamber 3 and incidentally
to or from the well 13. Both these valves are segmental in cross section and adapted
to rotate closely upon the circular side of the chamber 11 and are substantially
similar in construction except as hereinafter noted. A shaft M, common to both said
main valves K and I, is connected therewith as shown in the several figures. Thus,
in Fig. 8 is seen a sleeve 14 fixed rigidly upon shaft M and having a spur or
projection 15 adapted to engage in a corresponding recess or opening 16 in the
valve L, so that when the said shaft and its 'sleove are rotated the engaged pro-
jection 15 will turn valve L in the direction of their movement, whether one way or
another. Then to operate valve K, I provide another sleeve N, Fig. 6, having a
projection 17 engaging in a recess corresponding to the like recess in valve L, but the
sleeve N is free to be turned on shaft M. The valve L has itself a series of through
perforations, or openings, 18, covered by flexible or flip valves, 20, two such valvos
being used in this instance on said valve, and two others 21 of like character in
valve K. In order that none of these valves should open too far, I have provided
stop plates or their equivalent 22 on the inside of the main valves K and L. Both
said main valves are separately operative, the valve K being operative by a hand
lever O fixed upon the projecting outer extremity of sleeve N, while the valve L is
operated by treadle P, connecting rod 24 and shori arm 25 fixed on the end of
shaft M outside of lever O. The hand lever therefore controls the valve next to the
power cylinder, while the treadle lever controls the valve next to the hammer
chamber.
The valve chamber 11 is formed in the body A and turned out true, and a cap
plate 27 is set into the otherwise open end thereof. The shaft M and the sleeve N
project through this cap, and both ends of said chamber are suitably packed about
the said shaft to avoid leakage of air. Both the main valves K and I have right
angled projections 28 and 29, respectively, Fig. 7, which bear against sleeves on
shaft M, and both valves extend substantially the full length of chamber 11.
Extending upward from the air passage 12 in the wall of the chamber for the
hammer piston or head is an air passage 30, which has open communication at its
top with the top of the said chamber through a flip valve 31, arranged to close
the said passage 30, from above. In this way the air in said piston chamber
becomes compressed, especially above the side passage 12, when the hammer head
ascends, and the air at last forms a cushion for the said head, thus preventing the
head from striking the top of the chamber and also forming back pressure to
facilitate the downward stroke of the head by reason of the expansion of the
atmosphere. The passage 30, and the valve 3í also serve to allow inflow of ai

page_text: in the top of said piston chamber to accommodate the descent of the hammer
and to facilitate the drop by letting in a full volume of air through the passage 30.
In operation, when it is desired to deliver regular and uniform blows with the
hammer up to the full stroke thereof, it is my practice to open valves K and L to
their full extent, thus leaving an unobstructed passage of the air back and forth
through the passage 10 and 12. It will be understood that since the down stroke of
the hammer is produced mainly by the pressure of the air proceeding from the
upward stroke of the power producing piston C, the up stroke is produced by
the exhaustion of the air from the hammer head chamber and the atmospheric pressure
outside, and the air first passes in through passages 10 and 12 and then out through
the same passage, and the exhaustion from the hammer chamber by the power piston C
on its down stroke is equivalent to the pressure produced on its up stroke. So it
occurs that when the said piston C is down to the bottom of its stroke and past the vent
passage 33 in the power chamber 2, a certain amount of air will rush in to supply any
need occasioned by possible leakage in the machine, and thus restore atmospheric
equilibrium. However, when the parts are in perfect working condition and before
the piston C on its down stroke has passed the vent 33, the exhaust in the hammer
chamber and in the well 13 between said chambers should have been so complete as to
draw the hammer head by a quick stroke to the top limit of its movement. Then, too,
as the piston C returns on its up stroke, and when it has passed the valve outlet 34,
the atmosphere is again compressed and the hammer is actuated as before.
If it be desired to make a half blow, or rather to reduce the blow of the hammer
one half, the valve K will remain open and the valve L be half closed. It should
I have been stated that when open the valve L is carried downward, closing entirely the
passage 35 to the well. Hence if the valve L be half closed this passage 35 will be
only half open, and the surplus pressure, or the excess of one half will descend into
the well 13, and the well will thus take up what is not carried into the hammer
chamber. Further closing of the valve L will reduce the pressure or power in the
hammer chamber 8 correspondingly, and this reduction may be continued until
pressure is entirely cut off, in which case the hammer is suspended without movement,
notwithstanding the continued operation of the power piston C. If the valve L be
entirely closed as just suggested the atmosphere will be forced into and compressed
in the well and valve chamber, and withdrawn therefrom as the piston C descends,
and this alternate action will continue as long as passage 12 is closed. The well is
large enough to accommodate the needs of the machine in these extreme operations.
The hammer will be raised and suspended in raised position as long as valve L
remains closed, and by means of the treadle, which controls valve L, the operator
can graduate the blow from this dead point according to the needs of the work.
Indeed the strokes or blows of the hammer may be graduated with the utmost
nicety and may be run all the way from a very delicate touch down to an exceedingly
powerful blow. When the valve L is closed, as in Figs. 2 and 5, the flip valve 20
will permit air to be withdrawn from the hammer chamber, but will not permit the
air to enter therein and all air becomes instantly withdrawn from the said chamber
and the hammer is compelled to remain up until air is again admitted to said chamber
to allow it to descend.
If it be desired to make the hammer operate as a clamp or grip to hold an object,
the valve L is opened and the valve K closed, as seen in Fig. 5. This will permit air
to be forced in behind the hammer piston through flip valves 21 in valve K, but no
air can escape from said hammer chamber and the pressure will remain at the
maximum until valve K be again opened. There are also other uses of the said
valve K in the working of the machine, which are easily and quickly learned by any
one who is capable of operating the hammer.
Referring to Figs. 9 and 10, we find the principles of construction set forth in the
foregoing drawings and description also set forth in the said figures, but in a double
machine. That is, there is a single power piston chamber 40, large enough for all
purposes, and two hammer piston chambers 42, and two hammers 43 and 44. With
the exception that there are two hammers and corresponding chambers instead of one,

page_text: and a plurality of air passages 45 and 46 and of valves 47 and 48 there is no
essential difference in the construction of the double hammer and machine from the
single hammer and machine shown in the preceding figures, and it is not deemed
necessary to enter into a further description of this hammer for this reason.
Obviously two operations may be carried on at the same time with a double hammer,
or two hammers of the same or different sizes or styles may be employed, and one
operator may go from one hammer to the other and thus do in one heat what would
otherwise require two heatings to accomplish. This implies that different kinds of
hammers are needed to make the finished product and one or more hammer heads can
be used with a single power cylinder.
It should have been stated that each hammer in Fig. 9 has its own valve
operating mechanism consisting of treadles 70 and 71, respectively, and hand
arms 72 and 73.
Obviously many of the details of construction hereinbefore specified might be
modified or substituted and not depart from the spirit of the invention. Thus, for
example, direct acting instead of rotary valves might be used in the air passage
between the air reducing cylinder and the hammer cylinder, and still other parts
might be changed without avoiding the character or essence of the invention.
The hammer can be operated satisfactorily with the well 13 as a single chambor,
but I have found a more satisfactory operation by introducing a partition 80, thereby
sub-dividing said chamber into compartments a and b, the passage 35 leading to a
and the passage 37 to b. It will be noticed in Fig. 5 that if the valves K and L be
situated as therein shown the compartments a and b may be filled with compressed air
at an equal pressure, but the valve 21 will prevent the air from flowing back from
compartment a after piston C when it descends. It will, therefore, follow that
compartment a will remain full of compressed air while the piston C is running idle, and
the compartment & will take up the inforced air and the said air will expand back again
behind piston C, and thus prevent the taking in of fresh air through air inlet
opening 33 in cylinder 2. Thus the compartment a and the valve chamber above will
be filled with compressed air while as to compartment 6 there will be free play of the
air through passage 37 while piston C is running idle.
By this construction and arrangement I avoid excessive pressure in compartment a,
and tighten the running of the power piston, because the compartment 6 takes up and
gives back the air before the piston C, and thus tightens its stroke in both directions.
Otherwise, if the said compartiment b were not there the air before the piston C would
have to be forced through valve 21 and then in the back stroke there would be
vacuum which in turn would retard the down stroke.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In pneumatic hammers, a hammer chamber and piston and a power chamber
and piston, an air passage connecting one end of the power chamber with the
corresponding end of the hammer chamber, a plurality of valves in said passage and
separate means to operate said valves, substantially as described.
2. The hammer chamber and the power chamber and an air passage connecting
said chambers, a valve chamber in said air passage, separate valves in said chamber
and each of said valves having independent operating mechanism, substantially as
described.
3. The hammer chamber and the power chamber, a passage connecting said chambers
and a valve chamber in said passage, in combination with a shaft in said chamber,
separate valves on said shaft and separate means connected with said valves to operate
them, substantially as described.
4. The hammer chamber and the power chamber and the pistons in said chambers,
said chambers connected by an air passage, and a valve in said passage constructed
to be opened by suction from the power chamber and to be closed by pressure from

page_text: said chamber, whereby the hammer piston is held in suspension in its chamber while
the power piston is at work, substantially as described.
5. The hammer chamber and the power chamber and a passage connecting said
chambers, a valve chamber interposed in said passage, and a valve over the entrance
to said passage from said valve chamber to the hammer chamber and constructed
to open under suction from the power chamber and to close under pressure therefrom,
and means to hold said valve in its operative position, substantially as described.
6. The hammer chamber and the power chamber and an air passage connecting
said chambers, a valve chamber in said passage and a valve in said valve chamber
over the entrance to said passage from said valve chamber to said power chamber
and constructed to open under pressure from the power chamber and to close under
suction from said chamber, substantially as described.
7. In pneumatic hammers, the hammer chamber and hammer, the air compressing
and exhausting cylinder and piston, a valved air passage between said chamber and
cylinder, and a well in said passage, and a secondary valved air passage discharging
directly into the top of the hammer chamber, substantially as described.
8. The hammer described having a power piston and chamber and a hammer piston
and chamber and a valved air passage from the power chamber. to the compression
end of the said hammer piston chamber, and a well and a valve in said passage,
substantially as described.
9. The hammer chamber and the power cylinder and the piston therein, and a
valved air passage connecting said chamber and cylinder, and the said air passage
branched at the hammer chamber to discharge into the same at two different points
above the piston in said chamber, substantially as described.
10. The power chamber and piston, the said chamber having a vaived outlet at
about the middle of the stroke of the piston in said power chamber, in combination
with the hammer chamber and the piston therein and a valved air passage connecting
the said chambers, substantially as described.
11. The piston chamber, the power chamber having a valved outlet at or near
its middle portion and an air passage connecting said chambers, and a valve in said
passage constructed and arranged to close the passage to the hammer chamber by
pressure from the power chamber and to open by suction or exhaust from said power
chamber, substantially as described.
12. In pneumatic hammers, the hammer piston and chamber, the power piston and
chamber, a valved air passage connecting said chambers and an air well or pocket
opening to said passage, substantially as described.
13. In a pneumatic hammer, a body or frame formed with power piston and hammer
piston chambers, an air passage connecting said chambers and a plurality of valves
in said passage, substantially as described.
14. In a pneumatic hammer, a hammer piston chamber formed in vertical sections
and bands or straps to bind said sections together, substantially as described.
15. The hammer described having a power piston chamber provided with an outlet
at its top to the hammer piston chamber and a valved outlet near its middle emptying
into the open air, substantially as described.
16. In a pneumatic hammer, a hammer piston chamber and a power piston chamber,
an air passage connecting said chambers, a valve chamber in said passage, valves
in said valve chamber and means to control said valves, substantially
as described.
17. In a pneumatic hammer, an air passage connecting the hammer piston chamber
with the power pision chamber, a valve chamber in said passage, a well beneath
said valve chamber and a pair of valves controlling said air passage and said well,
substantially as described.
18. In a pneumatic hammer, the respective pistons and chambers and the single
air passage connecting the said chambers, a transverse barrel shaped valve chamber
in said passage, a pair of valves in said chamber, a shaft on which said valves are
separately mounted and separate valves connected with the above said valves,
substantially as described.

page_text: 19. In a pneumatic hammer, the power piston and chamber and the hammer piston
and chamber, and an air passage connecting said chambers having a valve chamber
and a compartmented well beneath said valve chamber and in communication therewith,
substantially as described.
20. The hammer chamber and the air compression chamber, a passage between
said chambers having an air well divided into two compartments and valves in said
passage to cut off the flow of air to and from the hammer chamber and to limit
the flow of air to said compartments, substantially as described.
21. The hammer chamber and an air passage leading to said chamber having a
valve chamber, a well beneath said valve chamber having two compartments and
valves in said valve chamber controlling the openings to said compartments,
substantially as described.
Dated this 20th day of Santember 1896
ALLISON BROS.,
Agents for the Applicant.