close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2126829

код для вставки
Aug. 16, 1938.
B. w. sNoDGRAss
2,126,829
MECHANICAL HAMMER
Filed Dec. 4, 1934
4 Sheets-Sheet l
5
0%
WW
O
4
5U”
n.
w
a
Aug. l6,_ 1938.
B. w. SNODGRASS
2,126,829
MECHANICAL HAMMER
Filed Dec. 4, 1934
4 Sheets-Sheet 3
Aug. 16, 1938.
B. w. SNODGRASS
2,126,829
MECHANICAL HAMMER
Filed Dec. 4, 1934
4 Sheets-Sheet 4
“MR
R“Fmm.
“ix
i%.Q
w
1W5?mow;
g@0m /,m%I m.”0%
7
4/72/7224/
2,126,829
Patented Aug. 16, 1938
UNITED STATES
PATENT OFFICE
2,126,829
MECHANICAL HAMMER
Benjamin W. Snodgrass, Denver, 0010.
Application ?ecember 4, 1934, Serial No. 755,907
4 Claims. (Cl. 255-42)
This invention relates to mechanical hammers, modi?ed somewhat in respect of the showing of
and more particularly to mechanical hammers of
Figure 1.
portable type adapted to operate tool elements
enlarged relative to Figure 6, taken on the indi
cated line 'I-1 of the latter ?gure. Figure 8
such as drills, chisels, formers, hammers, and the
5 like, and has as an object to provide an improved
arrangement and assembly of elements effective
to operate such tool elements in a practical and
e?icient manner.
A further object of the invention is to provide
1O improved means for actuating a reciprocating
impact element in a mechanical hammer.
A further object of the invention is to provide
improved means for operatively interconnecting
rotary power means and a reciprocable impact
15 element in a mechanical hammer.
A further object of the invention is to provide
an improved arrangement and assembly of ele
ments for operatively mounting a reciprocable
impact element in a mechanical hammer.
20
A further object of the invention is to provide
improved means automatically operable by the
25
is a cross section, on the same scale as Figure '7, ' U1
taken on the indicated line 8-8 of Figure 6.
Figure 9 is a fragmentary detail section, on a
further enlarged scale, illustrating certain de
tails of the showing of Figure 8. Figure 10 is a
longitudinal section axially of an improved ham- =
mer assembly still further modi?ed in respect of
the showing of Figure 1. Figure 11 is a cross
section, on a scale enlarged relative to Figure 10,
taken on the indicated line ll—ll of the latter
?gure. Figure 12 is a fragmentary detail section
of friction drive means employed in the assembly
according to Figure 10. Figure 13 is a fragmen
tary detail elevation of and at right angles to
the showing of Figure 12. Figure 14 is a longitu
dinal section axially of an improved hammer as
impact element actuating means to rotate the
sembly yet further modi?ed in respect of the '
showing of Figure 1. Figure 15 is a detail cross
shank of a tool cooperating with a mechanical
hammer.
ure 14.
A further object of the invention is to provide
improved means automatically operable by the
impact element actuating means to feed a tool
and mechanical hammer assembly toward the
work to be performed.
30
Figure '7 is a cross section, on a scale
A further object of the invention is to provide
an improved mechanical hammer susceptible of
practical development in a variety of speci?c
forms, readily adaptable to a wide variety of’
speci?c uses, positive and e?icient in operation,
35 relatively simple and inexpensive of manufac
ture, and requiring a minimum of maintenance
in use.
My invention consists in the construction, ar
rangement and combination of elements herein
40 after set forth, pointed out in my claims and
illustrated by the accompanying drawings, in
which
Figure 1 is a longitudinal section axially of a
hammer assembly embodying the principles of
“ the invention.
Figure 2 is a cross section, on an
enlarged scale, taken on the indicated line 2-2
of Figure 1. Figure 3 is a cross section, on the»
same scale as Figure 2, taken on the indicated
line 3--3 of Figure 1. Figure 4 is a fragmentary
detail section of and at right angles to the show
ing of Figure 3. Figure '5 is a fragmentary de
tail section, on the same scale as Figure 2, taken
axially of an air piston employed in the assembly
according to Figure 1. Figure 6 is a longitudinal
55 section axially of an improved hammer assembly
section taken on the indicated line l5—l 5 of Fig
In the construction of the improved" hammer
as illustrated in Figures 1 to 5, inclusive, the
numeral 20 designates a suitable frame member,
preferably formed as ahollow cylinder, arranged
to support and house the operative elements of
the assembly. One end of the member 20 is 30
closed, as by means of a removable plate 2|,
and suitable means, such as a T-handle 22, is
provided adjacent the closed end of the member
20 whereby the assembly may be conveniently
manipulated. Positioned in' axial alinement 35
within and adjacent the closed end of the mem
ber 20, an armature 23 of an electric motor as
sembly is mounted for rotation in suitable bear
ings carried by said member 20, the complemen
tary magnetic poles or ?elds of the motor as
40
sembly being indicated at 24 surrounding the
armature 23 in ?xed relation within the mem
ber 20 to complete a power unit carried by and
housed within said member, alined with the
armature 23, a relatively long, tubular impact
element 25 is positioned axially within the mem
ber 20 and ?otatively mounted for free rotation
and reciprocation relative to said member in
suitable spaced anti-friction bearings 26 carried
by said member. The end of the element 25
adjacent the armature 23 is closed save for a
splined central aperture arranged to slidingly
receive a splined portion of the extended arma
ture shaft 23', thus engaging the element 25 and
armature 23 for simultaneous rotation and feath 55
2
2,126,829
ering the former to the latter for relative axial
reciprocation therebetween, the opposite end of
the element 25 being closed by means of a pref
erably replaceable impact head 21. To utilize
rotation imparted to the element 25 by the arma
ture 23 to effect reciprocation of said element,
an annular race or track 28 is ?xed to the
member 20 between the bearings 26 in surround
ing relation with the element 25, said race 28
10 being provided with a plurality of uniformly
spaced cam bosses 29 projecting‘ from that
race surface most nearly adjacent the motor
assembly and arranged to cooperate with a freely
rotatable cam follower 30 carried exteriorly of
15 the element 25 on a stud or spindle ?xed to and
projecting radially from said element, so that,
as the element 25 is caused to rotate, the cam
follower 30 is caused to traverse the race 28 and
ride over the cams 29 thereof, each said cam
imparting axial displacement to the said element
25 in the direction of the motor assembly. Travel
of the element 25 in the direction of the motor
assembly is limited and reverse travel of said ele
ment initiated by a resiliently yieldable member,
25 illustrated in this instance as a frusto-conical
sheet spring 3|, ?xed within the member 20 ad
jacent the race 28 in surrounding relation with
the element 25 and in the path of an annular
?ange 32 ?xedly carried by said element 25, the
30 resiliently yieldable member being arranged for
compression toward and expansion away from
the motor assembly, so that motion of the ele
ment 25 toward the motor assembly results in
engagement of the ?ange 32 with the resilient
35 member 3|, compression of the latter, limitation
of the travel of the ‘moving element in the one
direction and initiation of travel of said element
in the opposite direction through recovery of the
resilient member, thus establishing a complete
cycle of reciprocation for the said element 25.
The tool element to be acted upon by the impact
dinal bore of the drill tool upon impact engage
ment of said head with said tool.
In the modi?ed construction of the improve
ment as illustrated in Figures 6 to 9, inclusive,
the operating elements are substantially the same
in function and interrelation as previously set
forth and are modi?ed only in respect of certain
additions and equivalent substitutions. In the
modi?ed construction, the frame member 20 and
motor elements 23 and 24 are the equivalents of 10
and may be identical with those aboverdescribed,
but the handle 22 is omitted and the member 20
slidingly mounted on and arranged for travel
along a ?xed feed frame 40, which latter is swiv
eled, as at 4 I, to a suitable tripod or other mount, 15
as is common practice. The frame 40 includes a
longitudinally disposed, ?xed lead screw 42 en
gaged by an internally-threaded pinion 43 car
ried by the frame member 20 concentrically with
and- for travel along said screw 42, said pinion 20
43 meshing with a gear 44 ?xed to the armature
shaft 23' for rotation therewith within the mem
ber 28, to the end that rotation of the armature
23 shall act through the gear 44 and pinion 43 to
move the latter along the screw 42 and thereby 25
advance the member 20, with its included ele
ments, alongthe frame 40. The impact element
25, mounting bearings 26 and head 2'! of the
modi?cation are substantially, and might well be
actually, identical with those above described,
but in the modi?cation the element 25 is spaced
somewhat from the armature shaft 23’ and is
connected to the latter for rotation therewith by
means of an axial stem 45 ?xed to said element
25 and terminating in a splined or angular head
46 slidingly received within a complementary
bore formed in the said shaft 23’. The race 28,
cams 29 and follower 30 of the modi?cation cor
respond closely with those elements as ?rst de
scribed and cooperate to the same end, but the
resilient element of the modi?cation is illustrated
element 25 is illustrated as a drill shank 33 _ as an expansive coil spring 41 surrounding the
loosely mounted in axial alinement with the said
element 25 through a bore formed for that pur
45 pose in the terminal extension 20’ of the member
20, said shank 33 being provided with an annular
stop ?ange 33' arranged to limit extension of
said shank within the portion 20’ and adapted
to be engaged at times by a retaining fork 34
50 hinged to the portion 20’ in position to embrace
the shank 33 and prevent accidental unseating of
the latter. Within the portion 26’ of the frame
and positioned adjacent the normally-located
inner shank end, a second resilient element in
55 the form of a frusto-conical sheet spring 35 is
arranged in the path of the impact head 2'! and
in surrounding relation with the shank 33 to
receive and absorb impact of said head when
said shank is dismounted or whenever overtravel
60 of the impact element might result from any
cause. When the hammer assembly is to be em
ployed in drilling operations, it is desirable that
means be provided operable to jet air through
and to the working face of the drill tool, such
65
means being illustrated as comprising a piston
36 closely ?tted within and freely reciprocable
axially of the hollow impact element 25, said ele
ment being provided with an air inlet 31 adja
70 cent its non-impact end and said piston being
provided with suitable air passages 38 controlled
by a check valve 39 arranged to utilize the iner
tia effect of said piston during reciprocation of
the impact element to jet air through a bore in
75 the impact head 21 registering with a longitu
stem 45 and positioned in the member 20 between
the gear 44 and impact element 25 and arranged
for end engagement by the latter, the function
and action of said spring 41 being essentially
identical with the function and action of the pre
viously described resilient element 3|. As shown
in Figures 6 and 8, a separate tool holder or
chuck 48 is rotatably carried in the impact end I
of the member 20, said chuck being arranged to
loosely receive the tool shank 33 and being pro
vided with radial notches wherein radial webs 49
formed on the tool shank 33 are engaged to ro
tatably interconnect the chuck and tool shank. 55
As one means of automatically rotating the
chuck 48, spirally inclined segmental surfaces
50 are shown formed on an inner face of the
chuck body, which faces are adapted to be en
gaged at the end of an impact stroke of the ele 60
ment 25 by the ends of pins 5| carried in axial
parallelism by and extending from the impact
head 21.
In the modi?cation according to Figures 10 to
13, inclusive, is illustrated an improved hammer 65
assembly particularly adapted for use in stoping
operations common to mining. As shown in Fig
ure 10, this modi?cation employs an impact ele
ment 25 provided with the annular ?ange 32
mounted for actuation within the frame 20 in the
manner shown‘ in Figure 1 and-hereabove de
scribed. In place of the resilient element 3| of
Figure 1, an expansive coil spring 41' similar to
the element 41 of Figure 6 is employed in the
manner and for- the purpose described for the
3
2,126,829
element 3|, the track 28-, earns 29 and follower 30
being included to function as hereabove set forth,
and the non-impact end of the element 25 is
splined to one end of an extended armature shaft
23' for rotation therewith and travel axially
thereof. The tool shank 33 is mounted in and
extends loosely through a chuck 52 rotatably car
ried in and adjacent the impact end of the mem
ber 20, said chuck being formed with or having
10 secured thereto a star wheel 53 with which a
radial lug or ?nger 54 ?xed to a shaft 55 rotat
and stem ‘H to actuate ‘the element 25 toward the
motor assembly and into end engagement with
the resilient coil spring element My disposed in
the member 20 in surrounding relation with the
stem ‘H and intermediate the shaft 58 and im
pact element 25. The modi?cation is provided
with the rotatable chuck 52, star wheel 53, radial
?nger 54 and shaft 55 illustrated in Figure 10 and
hereabove described, said shaft 55 in this instance
being provided with a terminal friction cone 13
'yieldingly held by means of an expansive coil
ably disposed longitudinally of the member 20 is
adapted to cooperate in such manner as to ad
vance the star Wheel one point for each revolu
tion of the shaft 55, thus intermittently rotating
the chuck 52 and tool element carried thereby.
To rotate the shaft 55, a friction cone 56 is
splined to the armature shaft 23' between the
motor assembly and element 25 and is yieldingly
positioned axially of said shaft 23' by means of
an expansive coil spring 51 engaging between
said cone 56 and an annular rib ?xed to said
shaft 23', and a complementary friction cone 5B
is splined to the shaft 55 and yieldingly posi
tioned thereon by means of an expansive coil
spring 59 engaging between said latter cone and
an annular ?ange 60 ?xed to the shaft 55, so
that, as the element 25 approaches the impact
end of its stroke, the friction surfaces of the
30 cones 56 and 5B are brought into engagement to
transmit rotation of the former to effect rotation
of the latter and consequently of the shaft 55,
the yieldable positioning of the said cones per
mitting disengagement of and slipping between
their friction surfaces whenever resistance to
rotation of the chuck 52 is encountered. To ad
vance the hammer assembly in the direction of
drilling operations, a tubular sleeve 6! is mounted
for rotation and held against axial displace
ment in and axially of a conical extension 62 of
spring ‘M in driven relation with a friction cone
75 mounted on and for rotation with the shaft
58. An impact block 15 is mounted for limited
axial motion in the member 28 adjacent the .chuck
52 and is arranged to bear against the inner end
of the tool shank 33 and transmit to said tool
shank impact received from the element 25,
said block 15 being formed with a peripheral
channel communicating through radial bores 1'! 20
with a central port 18 adapted to register with
the air bore of the tool shank, so that air sup
plied to the peripheral channel of the said block
may be led to and for discharge through the said
air bore of the tool shank. To supply air to the ~25
peripheral channel of said block, an air pump
in the form of an impeller 19 secured to the shaft
68 within a chamber carried within the member
20 is arranged to draw air through suitable ports
80 formed in the member 20 and discharge said 30
air, under pressure, through a conduit 8| connect
ing said'chamber with the peripheral channel of '
the said block 16.
.
It will be noted that all of the constructions
illustrated and described provide mechanical
means for converting rotary motion of an inte
gral power unit to effect reciprocation of an im—
pact element, said reciprocation being generated
and maintained by power actuation of the im
pact element in the .direction of and against a 40
the member 20 secured to and projecting axially
resilient element for reaction therefrom, free of
from the motor end of said member. The sleeve
6! is provided with a star wheel 63 secured to its
inner end and an. internally-threaded portion
adjacent its outer end, and a threaded stem 64
threadedly engages within said sleeve and is
formed with a bearing point 64' feathered
mechanical restraints, to Work effect on a rela
through and projecting beyond the outer end of
the extension 52, so that rotation of the sleeve
6! in one direction acts, through its threaded en
gagement therewith, to axially extend the bear
ing point 64’ through the frame extension 62
and consequently urge the hammer assembly
away from the bearing engaged by the point 64’.
To rotate the sleeve 6|, the shaft 55 is extended
past the motor assembly and provided with a
second radial ?nger or lug 65 positioned in oper
ative relation with the star wheel 63 and ar
ranged to act through the friction drive of the
60 cones 55 and 58, above described, to intermit
tently advance said star wheel 63 and rotate the
sleeve 6|.
In the modi?ed construction illustrated in
Figures 14 and 15, rotation of the armature 23
is transmitted through suitable bevel gears 66
and 51 to effect rotation of a shaft 68 disposed
transversely of the member 20 adjacent the mo
tor assembly, said shaft being provided with a
plurality of cam lobes 69 disposed in a common
plane radially thereof and arranged to operatively
engage a cam follower ‘l0 rotatably carried on the
end of a stem ‘H extending in ?xed relation from
the impact element 25 through a ?xed guide 12
carried by the member 20, so that rotation of the
shaft 68 acts through the lobes 69, follower ‘l0
tively ?xed, elastic element, and consequent re
action after work effect in the direction of re
peated power acceleration, the various speci?c 45
embodiments of the invention illustrated being
all effective to the same end and each presenting
a practical and operable construction for a com
plete, portable, powered, mechanical hammer
unit that is highly ef?cient in operation and
adaptable to a wide variety of uses in the ?eld.
. Since the various mechanical re?nements and
adjuncts of the improved hammer illustrated and
described in‘ connection with speci?c embodi
ments of the invention may be employed with and 55
applied to other embodiments of the said inven
tion, and since modi?cation of and variation in
the speci?c form, construction and arrangement
of the elements shown and described may be had
Without departing from the spirit and essence of
the said invention, I wish to be understood as
being limited solely by the scope of the appended
claims, rather than by any details of the illustra
tive showing and foregoing description.
I claim as my invention:
1. In a mechanical hammer, a casing having
front and rear sections, a power unit mounted
in the rear portion of the rear section, a rotatable
chuck at the front end of the front section, a
tool having a bored shank extending through said 70
chuck into the front section and having an im
pact block at its rear end formed with air pas
sages leading from the bore of the tool shank, an
impact member freely slidable longitudinally in
the front section towards and away from the im 75
4
2,126,829
pact block and having a stem extending into the
rear section and provided with a follower at its
rear end, a spring in the rear end of the front
section about said stem spaced from the rear end
of the impact member for the major portion of
movement of the impact member and engageable
by the rear end of said impact member to check
rearward movement of the impact member and
impart rebound thereto, a driven shaft rotatably
mounted in the rear section transversely thereof,
a spiral cam carried by said shaft for engaging
said follower to'shift the impact member rear
wardly during rotation of the shaft, a fan hous
ing in the rear section, a fan in said housing car
15 ried by said driven shaft, an air conduit leading
from said housing to the forward end portion of
said front section for delivering air to the air
passages of said impact block, means for impart
ing rotation to said shaft from said power unit,
and means for transmitting rotary motion from
the driven‘ shaft to the chuck.
2. In a mechanical hammer, a casing having
front and rear sections, a power unit mounted
in the rear portion of the rear section, a rotatable
25 chuck at the front end of the front section, a tool
having a bored shank extending through said
chuck into the front section and having an im
pact block at its rear end formed with air pas
sages leading from the bore of the tool shank, an
30 impact member freely slidable longitudinally in
the front section towards and away from the im
pact block and having a stem extending into
the rear section and provided with a follower at
its rear end, a spring in the rear end of the front
35 section about said stem spaced from the rear end
of the impact member for the major portion of
movement of the impact member and engageable
by the rear end of said impact member to check
rearward movement of the impact member and
40 impart rebound thereto, a driven shaft rotatably
mounted in the rear section transversely there
of, a spiral cam carried by said shaft for engag
ing said follower to shift the impact member rear
wardly during rotation of the shaft, a fan hous
45 ing in the rear section, a fan in said housing car
ried by said driven shaft, an air conduit leading
from said housing to the forward end portion
of said front section for delivering air to the air
passages of said impact block, a friction disk
carried by said driven shaft, a friction disk car
ried by said power unit and engaging the fric
tion disk of said shaft for imparting rotation to
the shaft from the power unit, a transmission
shaft extending longitudinally through the front
section and into the rear section, means for trans
mitting rotation from the friction disk of said
driven shaft to said transmission shaft, and means
for intermittently transmitting rotation from said
transmission shaft to said chuck.
3. In a mechanical hammer, a casing having
front and rear sections, a power unit mounted
in the rear portion of the rear section, a rotat
able chuck at the front end of the front section, a
tool having a bored-shank extending through said
chuck into the front section and having an im 10
pact block at its rear end formed with air pas
sages leading from the bore of the tool shank,
an impact member freely slidable longitudinally
in the front section towards and away from the
impact block and having a stem'extending into 15
the rear section and provided with a follower at
its rear end, resilient means in the rear end of the
front section spaced from the rear end of the im
pact member for the major portion of travel
thereof and engageable by the impact member to ‘
check rearward movement of said impact mem
ber and impart rebound thereto, a driven shaft
rotatably mounted in said rear section driven from
said power unit and carrying a cam member for
engaging the follower and shifting the impact
member rearwardly, a source of air under pres
sure in said rear section actuated by said driven
shaft, an air conduit leading from the source of
air under pressure to the front end of said front
section for delivering air to the air passages of 30
the impact block, and means for imparting ro
tation to the chuck.
4. In a mechanical hammer, a casing, a power
unit in the rear portion of said casing, a chuck
at the front end of said casing, a tool having a
shank extending through said chuck into the eas
ing, an impact member freely slidable longi
tudinally in said casing towards and away from
the rear end of the tool shank, a stem for said im
pact member extending rearwardly in said casing, 40
a cup mounted in said casing about said stem, a
spring in said cup spaced from the rear end of
said impact member for the major portion of
movement of the impact member and engageable
by the rear end of the impact member to check 45
rearward movement of the impact member and
impart rebound thereto, a driven shaft rotat
ably mounted in said casing and rotated from
said power unit, a cam carried by said shaft, and
a follower carried by said stem for engaging said 50
cam whereby reciprocating motion will be im
parted to said impact member during rotation of
said driven shaft.
BENJAMIN W. SNODGRASS.
55
Документ
Категория
Без категории
Просмотров
0
Размер файла
858 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа