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Патент USA US3076687

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Feb. 5, 1963
J, R, ANDERSQN '
'
3,076,674
TONGS
Filed July 21, 1960
'2' Sheets-Sheet 1
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73
INVENTOR.
JOHN E A/vafwo/v
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Feb. 5, 1963
3,076,674
J. R. ANDERSON
TONGS
Filed July 21. 1960
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INVENTOR.
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JOHN A? ANOEP'J‘ON
BY
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Feb. 5, 1963
3,076,674
J. R. ANDERSON
'IONGS
Filed July 21, 1960
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INVENTOR.
BY
Feb. 5, 1963
J. R. ANDERSON
3,076,674
TONGS
Filed July 21. 1960
‘T Sheets-Sheet 4
Feb. 5, ‘1963
J. R. ANDERSON
3,076,674
' TONGS
Filed July 21, 1960
'T Sheets-Sheet 5
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INVENTOR.
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Feb. 5, 1963
J. R. ANDERSON
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TONGS
Filed July 21, 1960
'7’ Sheets-Sheet 6
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Feb. 5, 1963
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3,076,674
TONGS
Filed July 21. 1960
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INVENTOR
JON/V2 ANDERSON
United States Patent 0
""
CE
1
3,076,674
Patented Feb. 5, 1963
2
pressure applied to such work for lifting, shifting or other
3,076,674
handling of it;
TONGS
FIGURE 12 is a view taken along line XII-XII of
John R. Anderson, Pittsburgl1,,Pa., assignor to Heppen
stall Company, Pittsburgh, Pa., a corporation of Penn
FIGURE 11;
Filed July 21, 1960, Ser. No. 44,329
FIGURE 11;
12 Claims. ,(Cl. 294-103)
-
FIGURE 13 is a view taken along line XIII—XIII of
sylvania
FIGURE 14 is a side view of another embodiment of
this invention in a tongs of the double lever class;
'
This invention relates to 1a relatively lower head
, FIGURE 15 is a side view partly in section of the em
room tongs’ of the lever class in which there is a relatively 10 bodiment shown in FIGURE 14 with the work subjected
fast and wide range of initial adjustment of work-engaging
to initial gripping pressure of the shoes;
shoes and ‘then full gripping pressureupon ‘lifting of the
FIGURE 16 is a view of the embodiment shown in
lever means. More particularly, this invention relates to
FIGURE 14 with work engaged and the tongs about to
tongs of the single, or double, lever class in which there
lift such work;
is one provision‘tfor relatively 'quickly moving the tongs 15
FIGURE 17 is a partial view taken along line
shoes into initial engagement with the work to be handled
XVII-~XVII of FIGURE ,16; and
‘and squeeze gripping thereafter for safe lifting upon rais
FIGURE 18 is a view taken ‘along line XVIII-XVIII
ing of the lever or levers.
of FIGURE 16.
In the lifting or other handling of work, such as coils
Referring to FIGURES l to 8, inclusive, of the draw
of metal, with tongs, it is desirable to have a tongs which 20 ings, one embodiment 10‘ of this invention is provided
will hang from a crane hook or other suspending device
with an inner shoe 11 and an outer shoe 12 between
in relatively level position, whether the tongs is loaded
which work, which may be in the form of a coil 13 at a
or unloaded and whether or not the work-engaging shoes
given time, is adapted to be initially and then fully
thereof ‘are open or closed. Further, such a tongs should
gripped to enable tongs 10 to lift or shifty-it as desired,
have a relatively wide adjustment between the shoes to 25 Tongs 10 is of the so-called single lever class and has a
handle the greatest possible number of sizes of loads
rigid frame comprising a flat vbase plate 14 and laterally
likely to be encountered. At 1the same time, the travel
spaced upstanding walls 15 a?ixed ‘thereto, the base being
of the respective shoes toward one another moving into
adapted to rest'upon the top of a coil to be handled with
initial engagement with work to be handled should be
one radial thickness of the coil in the space between
relatively fast, whether such travel is accomplished auto 30 shoes 11 and 12. A bracket 16 is secured to the under
matically by proximate vor remote control, or manually,
side of plate 14 and provided with a succession of trans
as desired. And, it should be equally convenient to open
the shoes as widely as desired and quickly so that the
tongs can be set down promptly on the next work object,
or on a stand while awaiting the next shop call for such
purpose.
At all times, the ?nal gripping of the work
must be certain and secure so as not to endanger person
nel or equipment in the course of any lifting of ‘that work
by the tongs. These various objects are accomplished in
verse registering openings 17 for pins 18 adapted to hold
shoe 11 in selected longitudinal position in accordance
with the position of its shank 19 extending rearwardly
of the shoe, ‘alternate positions being illustrated in FIG
URE l. Pins 18‘ may be held in place by snap rings or
cotterpins. Shoe 11 is preferably provided with a convex
face to abut the inside of a coil which the tongs is to
handle. Such coils come in different heights due to dif
a‘ way not heretofore possible, by embodiments of the 40 ferent widths of strip in the respective coils, and also
come in a wide variety of weights and thicknesses meas
instant invention which, moreover, operate with a rela
tively lower headnoom requirement.
ured radially from the innermost wrap to the outermost.
Other objects, features and advantages of this invention
will be apparent from the following description and the
accompanying drawings, which 2are illustrative ionly, in
which:
‘
,
FIGURE 1 is a side view of one embodiment of this
invention in a tongs of- the single lever class;
FIGURE 2 is a front view of the embodiment shown
in FIGURE 1;
.
FIGURE 3 is a side view partly in section taken along
line III—-II‘I of FIGURE 2;
V
7
FIGURE 4 is a side view partly in section of the em:
In the illustrated embodiments, the coils being handled
are coiledunder tension which provides relatively tight
45 wraps.
In view of the range of work or coil sizes found
in many plants, it is desirable to have a tongs available
which will accommodate the greatest number of such
sizes, thereby reducing equipment and handling costs.
An [outer shoe bracket 20 is provided of generally
L-shape in side elevation with transversely spaced side
members 21 between the lower ends of which is ‘affixed
a shank 22 extending forwardly of outer shoe 12 so that
bodiment shown in FIGURE 3 in which the shoes have _
it may be secured to bracket 20 by a bolt and nut as
sembly 23. The longitudinally extending walls 15am '
been closed to initially engage the work and full gripping
pressure ‘applied to such work for lifting, shifting or other
opposed and somewhat projecting bearing strips 24 iaffixed
handling of it;
to the walls 15. The bearing strips are slidably engaged
by guide recesses 25 in the outer sides of the respective
FIGURE 5 is a view taken along line V—-V of FIG
URE 4;
.
FIGURE 6 is a view taken along line VI--VI of
FIGURE 3;
members 21, which members are cross connected by bolt
and spacer assemblies 26. Shoe 12 preferably has a con
cave face as shown in plan in FIGURE 5.
.
FIGURE 7 is a view taken along line VII-VII of
FIGURE 4;
provided over the forward portion thereof with inwardly
'
FIGURE 8 is a view‘ taken along line VIII--VIII of
FIGURE 7;
FIGURE 9 is a side view partly in section of another
embodiment of this invention;
-
A nut 27 is provided with laterally extending mount
ing bosses 28 which ?t into registering openings 29‘ in
sides 21- so that as nut 27 is moved, it will corresponding
ly move bracket 20 and movable shoe 12, a forwardly
extending opening 14a in plate 14-being provided to per
mit a relatively wide range of movement of such shoe.
As shown, nut 27 is of the “ball screw” type and coop
crates‘ with a ball screw threaded shaft 30. The thread
URE 9;
‘ FIGURE 11 is aside view partly in section of the em 70 ing of the shaft and nut may take other complementary
bodiment shown in FIGURE 9‘ in which the shoes have
forms, such as Acme, square or buttress, threads, if de
sired. Threaded shaft 30 is provided with a smooth
been closed to initially engage the work {and full gripping
FIGURE 10 is a view taken along line X-X of FIG
3,076,674
4
cylindrical slide portion 31 at the rear having a spline
Lever brackets 65 extend upwardly and forwardly
way 32 therein to cooperate rwith a shorter key 33, the
from the frame to which they are a?ixed along the out
side of the ‘walls 15, spacing collars 66 welded to arms
62 and around fulcrum 63 being utilized to extend later
ally between bearing flanges __67 on bracket arms 65. An
nular stops 68 secured to pivot shaft 63 maintain it in
laterally outwardly projecting portion of which key en
gages a key-way in a drive sprocket 34. Suitable means
such as a thin spacing washer with an inwardly extend
‘ing ?nger may be used to cover the ends of the key and
hold it between the ends of the‘ sprocket.
place for rotation of lever 62 thereabout. The laterally
outer ends of shaft 63 extend beyond the positioning
A split front collar 35 and a split rear collar 36 are
?xed in position at the respective ends of the slide por
members 68 to act as a pivotal support for respective eyes
tion 31 and respectively engage annular bearings 37 and 10 69 ?xed to the lower ends of spring rods 70 in a connec
38 at different stages of an operation of the tongs 10.
tor counterbalance 71 to each side of the lever 62. Each
The annular bearings 37 and 38 are positioned adjoin
such counterbalance includes, as more fully illustrated
ing spool bearing ‘liners 39' and 40 in a front bearing
in FIGURES 3 and 4, a spring case 72- having a retainer
mount 41 and a rear bearing mount 42, respectively.
end 73 with an opening therethrough for spring rod 70.
Driven sprocket 34 is positioned between such bearing 15 The upper end of each case is ?xed to a bent member 74
liners of the respective mounts, which mounts are secured
which has an opening therethrough for pivotal connec
to frame plate 14.
tion to a counterbalance pin 75 extending through the
A reversible electric motor 43 with an integral reducer
laterally spaced plates in a lifting clevis 76. Clevis 76
is ?xed to a platform 44 supported by side angles 45
is pivotally connected at 77 to the upper outer end of a
and studs 46 which can be adjusted to select the height '
lever 62 and at 78 is provided with a necked spool sleeve
of motor 43 and keep a sprocket chain 47 taut. The
shaft of the motor 43 is fastened to a torque limiting
79 which is engageable by the crane hook 50. A spring
80 in each counterbalance 71 surrounds its respective
spring rod 70 and is retained between retainer end 73
and a retainer 81 ?xed at the upper end of the spring
rod. Each spring exerts a bias urging the clevis plate
76 into the position shown in FIGURE 1 for assistance
in keeping the base plate 14 and tongs 10 relatively hori
zontal.
friction coupling 48 which presses a driving sprocket 49
to drive sprocket 34 by means of chain 47 in either se
lected direction of rotation depending upon the stage of
the operation of tongs 10. The motor 43 may be con
nected to a portable pushbutton station control connected
thereto by suitable cables for operation by a person on
the ?oor of the shop or plant where tongs 10 is installed,
and/ or by a control station in the cab of a crane, for ex
A rearward extension 82 is provided on the arms of
30 lever 62 to support an automatic alternating cam latch
ample, having a hook 50 ‘from which tongs 10 normally
is suspended when it is being used to handle loads. A
ing and unlatching mechanism 83 having an inverted
sheet metal guard 51 may be used to cover the chain
reaches.
latch keeper 86, having a slot 85, ?xed to frame walls
T-headed latch bolt 84 to alternately cooperate with a
15.
The latch mechanism may be made in accordance
As sprocket 49 is rotated, it will correspondingly rotate 35 with the disclosure of US. Patent No. 1,839,389 or
the screw shaft 30.
When that rotation is clockwise as
viewed from the front of the tongs, the nut 27 will be
moved to the ‘left, as viewed in FIGURE 3, toward a
2,776,857 to alternately latch and unlatch as described
therein or in my copending application S.N. 55,779 ?led
September 13, 1960‘ for Tongs.
In a typical operation, tongs 10 may be latched open
clutch member 52 ?xed to the front end of shaft 30.
Conversely, when shaft 30 is rotated in a counterclock 40 with shoes 11 and 12 open a selected distance apart.
wise direction, the nut 27 will be moved to the right.
Lifting of the crane book 50 by the crane operator will
Generally, bracket 20 will be heavy enough to cause
remove the tongs 10 from a previously deposited coil and
some axial sliding of shaft 30 due to its rotation before
lever 62 will be in unextended position relative to the
there is any longitudinal movement of nut 27. Thus, a
frame from which it cannot lift because the latch bolt
rotation of shaft 30 to move nut 27 to the left will nor
head
is engaging the underside of the keeper as illustrated
mally ?rst cause the shaft to slide to the right until 45 in FIGURE 3. Moreover, spring 80 will be exerting its
collar 35 abuts bearing 37 before such movement of the
influence and shorten the distance between the pivots 63
nut starts to take place; on the other hand, when the nut
and 75 to keep pin 78 in the position illustrated in FIG
27 is to be moved to the right toward the sprocket, the
URES 1 and 3 with the center of gravity of the empty
shaft will usually slide to the left until collar 36 abuts
50 tongs generally directly below pin 78 and the cables from
bearing 38 before the nut begins to move.
which crane book 50 depends. By comparison, when
The front of clutch member 52 is provided in the il
tongs 10 is‘ carrying a load, clevis 76 and counterbalance
lustrated embodiment with a clutch engaging surface in
72 will move into extended position as illustrated in FIG
the form of teeth 53, or such engagement surface may be
URE 4 to shift pin 78 toward a position more directly
in the form of a frictional surface, or may have a castel
55 above the combined center of gravity of the combined
lated or other con?guration, which will prevent rotation
tongs and load. Thus, tongs 10 will hang relatively level
of shaft 30 when member 52 is longitudinally pressed by
in both loaded and unloaded condition.
an opposing clutch member 54 in the ‘form of a slidable
Continuing the operation; if it is now desired to lift
thrust block. The block 54 in the illustrated embodiment
another coil 13, whether or not of the same size of the
is provided with a clutch engaging surface 55 having
coil previously carried, tongs 10 is deposited thereon with
teeth to dovetail with teeth 53 when the clutch coupling 60 shoe 11 entering the eye of the coil and the parts of the
is effected. Block 54 is provided with longitudinally
tongs generally in the position illustrated in FIGURES l
extending lands 56 affixed thereto which slide in opposed
and 3. Thereupon, motor 43 is energized from the push
grooves 57 along the inner sides of the sides 21. A for
button station in a reverse direction to close the shoes
wardly extending link 58 on block 54 is pivoted between
65 Generally, the rotation of screw shaft 30 resulting there
bifurcated forwardly extending lugs 60 integral with
block 54, said lugs having registered holes therethrough
for the pivot pin 59 which also extends through an open
ing at the rear end of link 58. A pivot pin 61 pivotally ‘
connects the ‘forward end of link 58 to a ‘lifting lever 62
from will ?rst cause rear collar 36 to shift to the left as
viewed in FIGURE 3 and abut its bearing 38, where
upon nut' 27 will move outer shoe 12 toward the coil
until both shoes are in engagement with their respective
70 ly adjoining wraps with an initial gripping ‘pressure deter
mined by the setting of the torque limiting device 48 in
frictional engagement with driving sprocket 49. The
63 acting as a fulcrum and an offset or bell crank portion
slippage of device 48 normally occurring when the pre
64 extending downwardly below pivot 63 for the con
determined initial gripping pressure due to the force of
nection to link 58 by means of pin 61.
75 the motor is exerted is sufficient to maintain such initial
formed of laterally spaced arms between which such for
ward end extends. The lever 62 has a main pivot bolt
3,076,674
‘gripping pressure and to avoid stalling the motor. Dur
ing the travel together of the shoes 11 and 12 into vinitial
fgripping position, irrespective‘of the thickness of the work
to-be lifted by the tongs, the clutch members 52 and 54
remain out of" engagement and the lever 62 remains in its
collapsed (unextended) position relative to the base of
the tongs, even though the distance between nut 27 ‘and
pin 61 has been increased, without, however ‘increasing
6
‘dotted position shown in FIGURE 3 in alignment with
the slot 85, which unlatching movement will be com
pleted when crane hook 50 next rises to grip squeeze and
lift the new work following closure of the shoes thereon
to initial gripping position in the manner described above.
In the manual embodiment illustrated in FIGURES 9
to 13, inclusive, parts thereof corresponding generally
in construction and functioning to those set forth in the
embodiment of FIGURES 1 to 8 have been provided with
Consequently, when lever 62 is next lifted, its unlatching 10 the same‘ reference numerals respectively with the addi
the distance between'separated clutch members 52 and ‘54.
having ‘been completed in the course of crane hook 50
tion of a prime accent thereto and substantially all of the
commencing to rise after the initial gripping of the ‘coil
structure and operation of tongs 10’ will ‘be apparent
‘by the closed shoes, the safe lifting'gripping pressure that
upon reference to the description of such embodiment in
is applied will represent a relatively small upward move
FIGURES 1 to 8. In tongs 10', a driven gear member
ment of lever 62 and further movement together of‘shoes 15 34' is provided in the form of a worm wheel which is
Hand 12 compared with the possible normal travel of
operated by, a driving gear worm 100 keyed to a cross
those shoes from open to initial gripping position. More
shaft 101 journaled in side walls 15’. One end of shaft
over, irrespective of the size of the work to be handled,
101 projects through one side 15’ for attachment of a
the distance which lever 62 rises-above the base plate 14
hand wheel ‘102, which can be rotated in either direc
in reaching its extended position while applying the ?nal.
gripping squeeze before lifting safely, will be generally the
tion» to correspondingly rotate screw shaft v30’. Shaft
30' as shown is provided with an Acme thread to co
same distance. Thus, tongs 10 over the relatively wide
operate with a corresponding female thread on the in
range of work which can be handled within its capacity,
terior of nut 27’. Clutch member 52' at the front of
the overall height of ‘the tongs in lifting will remain gen
shaft 30 is provided with a conical roughened surface
erally the same and relatively low making it very suit-‘ 25 frictional face 53’. The ‘other clutch member in the
able for use under low ceilings‘ or in constricted areas.
form of thrust block 54' is provided with a conical recess
In‘ the case of tension wrapped coils, for example, the
maximum travel of the shoes from’ open to initial grip;
_ ping position may represent a matter of several inches,
55’ preferably also having a roughened frictional surface
to cooperate with surface 53’ when the- two clutch mem
vibers are pressed into clutching engagement by the lifting
while the ?nal gripping squeeze will be effective upon a 30 of lever 62' to hold shaft 30' against any rotation irre
further travel together of the shoes by movement through
spective of whether anyone should try to turn hand
wheel 102 at‘ that time. In general, the manual embodi
a matter of, say, one and one-quarter inches or less in
many cases, upon lifting of lever 62.
‘
‘
ment 10' would be utilized in smaller quarters, or for
“When unlatched lever 62 rises, it will exert its ?nal
a range of work which is smaller and/or lighter than
work for which the previously described embodiment
gripping pressure, or “grip squeeze,” in a manner illus;
trated in FIGURES 4 and‘ 7, for secure liftingbecause,
might be selected.
'
‘
of the ‘thrust of clutch block 54 against clutch member 52.,
Such pressing of clutch member 54 is provided by the
-A still further embodiment is illustrated in FIGURES
14 to 18, inclusive, of the drawings showing an embodi
ment of this invention in a'tongs of the double lever
movement of link 58 to the right as viewed in FIGURE
4 brought about by the counterclockwise swinging of off 40 class which might ‘be selected for very large and/ or very
, heavy coils or other work to ‘be handled by the tongs.
' set 64 about fulcrum 63 whenlever 62 is extended. The
engagement between clutch members 54 and 52 prevents
any rotation of shaft 30 in the illustrated embodiment be
In such still further embodiment, parts corresponding
generally in construction and functioning to parts in the
embodiment set forth in FIGURES 1 to 8 are provided
cause of the positive interlocking between the respective
sets of teeth 53_and 54 preferred therein because of the 45 with the same reference numerals, respectively, with the
generally“ frictionless relation between‘ the threads of
screwrrod 30 and “Saginaw” nut 27. Such thrusting to
the right as illustrated in FIGURE 4 torprovide the ?nal
addition‘of a double prime acent. In the embodiment
of FIGURES 14 to 18, a parallelogram linkage is pro~
vided comprising lever 62” and a generally opposed
lever ‘200, the respective ends of such levers being pivotal
a‘corresponding distance to the right so that the collars‘ 50 ly engaged by links 202 and 201, respectively. The links
gripping pressure movement will normally slide shaft 30
35 ‘and’ 36 will both be out of engagement ‘during‘lifting
with their respective bearings 37 and 38. ‘Consequently,
the lifting pressure will be exerted through the clutch
52—54, nut 27, the frame and shoes and not through the
collar 35 and the bearing mounts.‘
v
,
When coil 13 is deposited by lifting tongs 10, the _'I‘
head of latch bolt 84 will enter slot ‘85 and when the bar
rel 83d‘ of the latch strikes the keeper v86, it will partially
are pivotally connected at 203‘ to each other and to a
bail 204 for a crane hook or other supporting device
from which tongs 10" depends when in service. The
fulcrum .163" of lever 62", however, is swingably con
5.5 nected to brackets 205 integral with the frame by straps
206. A crossbar 207 is also pivotally connected at one
end to pivot 63” and at its other end to fulcrum pivot
bolt 208 for lever 200. Bar 207 is provided with a rear
rotate the bolt due to its cam action toward the latched
ward extension for latch keeper 86", such bar 207 com
position illustrated in FIGURE 3, which is completed
prising two parallel members, one on each side of motor
after the shoes are opened and crane hook ,50 next rises
to remove the empty tongs. Upon'such deposit'of coil
13, motor 43 is again energized to rotate shaft 30 in a
43" mounted on the tongs frame; the lever 200 and links
201 and i202 likewise also being laterally spaced double
members symmetrically positioned to each side of a lon
Such ‘rotation of screw shaft 30 can take place because
in setting coil 13_ down upon a ?rm support, the con
provided with pivots 210 for the lower ends of the later
ally spaced'arms of lever 200. Lever 62", which could
also be made up in the form of laterally spaced mem
gitudinal medial plane extending vertically through the
‘shoe opening direction moving collar 35 into abutment
with hearing‘ 37 and moving shoe ,12jto ‘the left to sep 65 axis of screw shafts30". Brackets 209 at the rear end
of the tongs frame in alignment with the ‘brackets 205 are
‘arateit "from shoe 'l'l'to‘release ‘the grip upon the coil;
tinued lowering of lever 62 disengages the clutch mem
ber 54 from member 52‘ and frees shaft 30‘ for rotation 70 hers, is joined to the laterally spaced members in link
202 by the pivot pin 212 and lever 200‘ is connected to
illustrated tongs 10. Then, whenthe empty latched tongs
is carried away to its next job, the setting of the tongs 10
link 201 by a like pivot pin 211. Latch 83" is af?xed
down on the work and lowering hook 50 will cause the
to the right-hand end of lever 62", which is bifurcated for
latch barrel 83a to strike the keeper 86 and the camming
that purpose, substantially in the location illustrated in
action will rotate the head of the latch bolt toward the
US. 'Patent No. 2,536,932 to cooperate with keeper 86"
3,076,674
8
7
in the manner hereinbefore described.
The levers fur
ther may be respectively cross connected by straps, in
lieu of using bar 207 if desired, to provide positive ver
tical extension and contraction of both sides of the lever
and link parallelogram action, in which event keeper 86"
would be affixed in cooperating position to a support ex
tending rearwardly from offset portion 213 of lever 200
to maintain keeper
shown.
The action of the
in tongs It)" and for
position by means of
‘86” substantially in the position
selectively rotating said shaft, a second clutch member
operatively connected to said frame in opposed relation
to said ?rst-named clutch member and movable in said
direction into and out of engagement with said ?rst-named
clutch member, and lever means to press said second
named clutch member into engagement with said ?rst
named clutch member as said lever means lifts to move
said shoes toward one another to grip said work with a
sufficient squeezing pressure to enable it to be lifted.
mechanism for opening the shoes
closing the shoes to initial gripping
motor 43", and of the latch 83", is
as previously described. Such mechanism is shown in
FlGURE 15 in initial gripping position with rear collar
36” being provided in the form of a thrust bearing held 15
2. A ‘tongs as set forth in claim 1 in which said frame
has a relatively horizontal base, said shoes extend below
said base and there is a latch mechanism to latch and
unlatch said lever means alternately and automatically.
3. A tongs as set forth in claim 1 in which said nut
and shaft are provided with complementary relatively
frictionless ball screw threads and said respective clutch
members are provided with surface portions which pro
A similar thrust bearing comprises front collar 35” held
vide a positive interlock with each other when said clutch
in place by an annular stop 215. The raceways on the
members are in engagement.
I
bearing mount side of the respective collars are rotatable
4. A tongs as set forth in claim 1 having a reversible
so that no annular bearings have to be provided on the 20
electric motor mounted on said tongs and operatively
outward faces of the respective bearing mounts 41” and
in position on the rear end of shaft 30” by a nut 214.
42". The threading on shaft 30" and in nut 27" may
be a conventional friction threading. The rear of nut
27 ” is provided with an annular flange 216 which is bolted
fast to a cross yoke 217 extending between the rear ends 25
of shoe bracket sides 21" to which said yoke is a?ixed.
The yoke 217 is provided with an opening through which
connected to said shaft and a torque limiter interposed
between said motor and shaft ineffective to turn said
shaft when said clutch members are engaged irrespective
of whether or not said motor is energized.
5. A tongs as set forth in claim 1 in which said lever
means are either of the single or double lever class and
there are latch means for said lever means to hold the
shaft 36" extends. Clutch member 52" ?xed to the shaft
latter in collapsed condition at predetermined times.
39" is in the form of a conical frustum and preferably
6. A tongs comprising, in operatively connected com
is made of a friction material to cooperate with the com 30
bination, a longitudinally extending frame, work gripping
plementary recess surface 55" of thrust block 54". The
forwardly extending laterally spaced lugs 60" of block
54" are directly connected to lever 62" by pivot pin 61"
in view of the movability of fulcrum 63" due to strap
206. Thus, as bail 204 begins to rise, with the levers and
links unlatched as illustrated in FIGURE 16, head pin
263 will increase its distance from base plate 14" extend
ing the levers 62" and 200 and links 201 and 202 to pro
vide a ?nal grip squeeze upon coil 13" for secure lifting
thereof.
Terms used herein for orientation such as “front,”
“rear,” “side” and movement directions are to be deemed
used in a relative sense.
Further, the illustrated em
shoes in opposed relation operatively connected to said
frame, slidable means mounting at least one of said
shoes for movement in a straight line longitudinal direc
tion toward and away from engagement with the other
shoe to grip or release work, a substantially non-rotatable
member operatively connected to said slidable shoe to
move it in accordance with movement of said member
either way in said direction, an engagement member
positioned in opposed relation to said ?rst-named mem
ber, opposed clutch means operatively and respectively
connected to said members, said engagement member
being movable along said straight line to cause engage
ment of said clutch means and ?x the distance between
bodiments may be utilized to pick up work of other shapes
said members, lever means operatively connected to said
and sizes, or to pick up two coils in side-by-side relation
with the respective shoes each engaging the innermost 45 second-named member to move said clutch means into
engagement as said lever means lifts to move said shoes
wrap in the eye of one of the respective coils. Still
relatively toward one another to grip said work with a
further, the automatic latch and keeper means illustrated
su?icient squeezing pressure to enable it to be lifted, and
may be replaced with other holding ‘9r latching means,
drive means for said ?rst-named member movable along
whether automatic, semi-automatic, or manual, as de
sired, whenever there is to be provision in a tongs of 50 said straight line to a limited extent and adapted to be
rendered inoperative upon said engagement of said
this invention for keeping the lifting lever means in col
lapsed condition between lifting assignments.
Various modi?cations may be made in details of the
clutch means.
7. A tongs as set forth in claim 6 in which said re
illustrated embodiments and other embodiments provided 55 spective members are a nut and thrust block and said
drive means includes a shaft provided with complemen
without departing from the spirit of my invention or
tary threads and said clutch means are provided with
the scope of the appended claims.
surface portions respectively which at least frictionally
I claim:
interlock with each other when said clutch means are
1.- A tongs comprising, in combination, a longitudinally
extending frame, work gripping shoes in opposed relation 60 in engagement.
8. A tongs comprising, in operatively connected com
operatively connected to said frame, at least one of said
shoes being mounted on a slidable bracket operatively
connected to said frame and movable in a straight line
longitudinal direction toward and away from engagement
with the other shoe to grip or release work, a substan
tially non-rotatable threaded nut operatively connected
to said bracket to move it in accordance with move
ments of said nut in said direction, a threaded shaft ex
bination, a longitudinally extending frame, work grip
ping shoes in opposed relation, one of which is ?xed to
said frame, a bracket carrying the other shoe and mov
able longitudinally in said frame, a non-rotatable nut
operatively connected to said bracket, a screw shaft ex
tending through said nut and adapted to be rotated to
move said nut and cause said other shoe to move rela
tending through said nut and having a slidable portion
tively to said ?rst-named shoe to initially grip work or
rearwardly of said nut operatively connected to said 70 to open a ?rst clutch member ?xed to the front of said
shaft ‘forwardly of said nut, said shaft being mounted
frame, a clutch member operatively connected to said
on said frame and longitudinally movable a limited
shaft forwardly of said nut, said shaft being movable
amount between respective end positions, reversible
to a limited extent rearwardly upon pressure being exerted
means for rotating said shaft in a selected direction, a
against said clutch member to press it toward the rear,
reversible means operatively connected to said frame for 75 second clutch member longitudinally movable along said
8,076,674
bracket into and out of engagement with said ?rst clutch
member, and a lifting lever operatively connected to
said second clutch member to urge it into engagement
with said ?rst clutch member to‘hold said shaft against
rotation and move it intermediate said end positions to
apply ?nal gripping pressure to work engaged by said
shoes when said lever is lifted from its substantially
lowest position relative to said frame.
10
rotate said rotatable means when said lever is in said
raised position relative to said frame.
11. A tongs as set forth in claim 10 comprising a
latch mechanism adapted to latch and unlatch said lever
when it is in lowered position relative to said frame.
12. A lever class tongs comprising, in operatively con
nected combination, work gripping members in opposed
relation with said members movable relative to one an
9. A tongs as set forth in claim 8 in which said lever
other, a not connected to one of said members, a
is of the single class and there is a latch to latch or 10 threaded shaft cooperating with said nut, lifting lever
unlatch said lever in or from collapsed position.
means, opposed engageable clutch parts respectively ?xed
101. A lever class tongs comprising, in operatively con
to said shaft and said lever means, said shaft also being
nected combination, a frame, at least one lifting lever
axially movable to a limited extent, reversible means for
connected to said frame, Work grips mounted on said
rotating said shaft to open said members or to close
frame in opposed relatively movable relation, a member
said members by movement relative to one another when
operatively connected to said ‘grips, rotatable means
said lever means are in lowered position, and means to
adapted to coast with said member to move said grips
operatively engage said clutch parts when said lever
relatively to one another to cause them to open and to
means are raised to prevent rotation of and move said
close and engage work with an initial gripping ressnre,
shaft axially to cause work to be lifted by said members.
drive means to rotate said rotatable means to move said
member for said coaction, and means adapted to be
moved by raising said lever relative to said frame to
hold said rotatable means against rotation and shift it
axially to cause said grips when in initial gripping pres
sure position to engage said work with a further grip 25
ping pressure, said drive means being inoperative to
References ited in the ?le of this patent
UNITED STATES PATENTS
2,803,489
2,830,842
2,925,300
2,945,609
Zito ________________ __ Aug. 20,
Heppenstall et al _______ __ Apr. 15,
Kelley ______________ __ Feb. 16,
Benes et a1. __________ .._ July 19,
1957
1958
1960
1960
UNITED STATES PATENT OFFICE
CERTIFICATE OF CORRECTION
Patent N00 3,076“674
February 5, 1963
John R, Anderson
It is hereby certified that error appears in the above numbered pat
ent requiring correction and that the said Letters Patent should read as
corrected
below.
‘
.
'
Column 4! line 19, ‘after "of", strike vout "a"; line 64'
after "shoes", insert a period; column 5, line 70, after
"rotation" insert =-- by motor 43, completing a cycle of opera
trons of the —-; column’ 8,, [line 703,‘ after "open" insert a
comma; column 9, line l8i for "and" read =-— or e-o
Signed and sealed this 27th day of August 1963,
(SEAL)
Attest:
ERNEST w. SWIDER
Attesting Officer
DAVID L- LADD
I
Commissioner of Patents
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