Note: Descriptions are shown in the official language in which they were submitted.
10'78891
The present invention is directed to a remote-controlled
safety hook which is used in moving heavy loads from one
location to another. More particularly, the present invention
is directed to a radio-controlled safety hook which contains
certain safety features which, substantially eliminate the
hazards normally associated with the movement of heavy loads
in various types of construction operations.
When a crane is utilized for moving large, heavy loads from
one location to another, for example, in various types of constru
tion operations, at least one and frequently two workmen are uti-
lized to guide the load into its proper position. Once the load
has been positioned, one of the workmen must walk onto the load
to unhook the choker from the load. In many instances, since the
load is located many feet above the ground, for example in the
case where the load is an I-beam which has been positioned in the
superstructure of a building which is being constructed, the re-
quirement *hat the workman walk onto the load to unhook the choke
from the load creates a definite safety hazard to the worker In
addition to the safety hazard) a considerable amount of time is
; lost when the workman is re~uired to perform such a duty.
In addition to the safety problems which presently exist in
the prior art, hook-type devices which are used in conjunction
with various loading, unloading, and relocating operations suffer
from a number of deficiencies. For example, because of the very
nature of tlle type of work being performed, the prior art hook-
type remote-controlled devices are susceptible to damage because
of the abuse which the hook must undergo during various types of
constructional operation. The radio receiver and the relay are
particularly sensitive to shock and thus, unless proper steps are
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taken to protect said devices against the shock which is normally associated
with heavy construction op~rations, the lifetIme of the remote-controlled
hook will be seriously limited.
Accordingly, an object of one aspect of the present invention is
substan~ially to minimize the prior art deficiencies associated with rem3te-
controlled hook devices which are utilized in relocating heavy loads from
one location to another.
An objec-t of another aspect of the present invention is to pro-
vide a system for automatically removing chockers from a load after the
load has been properly positioned.
An object of a further aspect of the present invention is to
provide means for mounting various components of the safety hook of the
present invention in order to protect them from sh~ck.
An object of still another aspect of the present invention is to
provide a safety hook wherein the hook itself can be manually released in
the event of a malfunction in the operation of the device.
An object of a still further aspect of the present invention is
to provide a radio-controlled safety~hook wherein the hook i5 automatically
locked when it is closed .manually and will not open again until either the
power is transmitted to the hook by a radio transmitter or the safety lock
is manually operated to release the hook.
An object of yet another aspect of the present invention is to
provide a safety hook assembly wherein the hook itself is readily accessi-
ble and free from interference with the shackles disp3sed on the device.
An object of a still furthor aspect of the present invention is
to provide a hook-shackle assembly wherein the shackles and the hook are in-
dependently supported by the frame through a common pin for producing a very
strong and stable assembly.
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-~' An object of still another aspect of the pre~ent invention is to
provide a safety hook assembly of sufficient weight so that it acts as a
headache ball for overhauling tEle line from the drum of the hoisting equip-
ment, thereby substantially eliminating the need of a separate headache
ball or weight.
An ob~ect of another aspect of the present invention is to pro-
vide a battery installation for the safety hook assembly which facilitates
the ready introduction and removal of the battery from the safety hook when
the battery becomes inoperative.
An object of still another aspect of the present invention is to
provide a worm gear-motor-hook assembly which provides for a smooth opera-
tion of the hook from a closed to an open position in response to a radio
signal received by a radio receiver disposed on the safety hook assembly.
By one broad aspect of this invention, a remote-controlled safety
hook assembly is provided which comprises a supporting frame, a hook-
shaped member rotatably disposed within the supporting frame, at least one
shackle means suspended from the supporting frame, a power supply means
disposed in the supporting frame, a receiver means for receiving specified
control signals disposed in the supporting frame and a relay means opera-
tively connected with the receiver means, drive means disposed in thesupporting frame, a gear assembly operatively connected with the drive
means and the hook-shaped member for automatically swinging the hook-shaped
member from a closed position to an open position in response to specified
control signals and a cut-off switch means and a close switch means dis-
posed for engagement with the hook-shaped member in its open position, both
of the switch means releasing all electrical power to the hook-shaped member
when the hook-shaped member is open and the close switch means simultaneous-
ly disengaging the receiver means and the relay means from the hook-shaped
B ~ member, thus preventing possible damage to the receive~ means the relay
means and the power supply means.
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~ 7889~
By one variant thereo~, the po~er su~ply means is a battery.
By another'variant, the assembly further comprises a lug means
attached to the hook-shaped member', and a load safety swîtch disposed for
engagemen~ with the lug means so that when the hook-shaped member is placed
under load, the lug means engages the load safety switch, thereby elimina-
ting all power to the hook-shaped'member;
By a variation thereof, the shackle means îs spring biased.
By another variation, the spring-biased shackle means has a
substantially U-shaped configuration with the free ends of the shackle
means being rotatably connected to the supporting frame.
By yet another variation, the shackle means is spring biased
and extends latèrally with respect to the hook-shaped member, the shackle
means being rotatably suspended from the supporting frame.
By a still further variation, two spring-biased shackles are
utiliæed.
By another variation, the gear assembly contains a safety lock
mounted therewith and a disk-like element, the disk-like element being
mounted for rotation in response to the drive means, and 'being provided on
one side thereof with means for disengaging the safety lock for releasing
the hook-shaped member for counterclockwise movement.
By another variant, the safety switch is attached to the safety
lock for engagement with the lug means.
By another variation, the disk-like element is provided with a
pin means on the other side thereof and the hook-shaped member is provided
with a connecting arm which is adapted to engage and disengage with the
pin means in response to the rotation of the disk-like element, the hook-
shaped member moving from a closed to an open position during such move- '
ment.
By another variation, an additional switch means is operatively
, 30 associated with the gear assembly and is mounted for providing continual
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~78891
` rotation of the disk-like element7 thereby releasing the sa~ety lock to
a position for locking ~he hook-shaped member when such member is manually
closed.
By another variant, spring means are operatively associ~ted with
the hook-shaped member for holding the hook-shaped member in either an
open or closed position.
By a further variant, the shackle means is spring biased.
By a variation thereof, the spring-biased shackle means has a
substantially U-shaped configuration with the free ends of the shackle
means being rotatably connected to the supporting frame.
By another variant, the shackle means is spring biased and
extends laterally with respect to the hook-shaped member, the shackle
means being rotatably suspended from the supporting frame.
By a variation of that variant, two spring-biased shackles are
utilized.
By another variant, the gear assembly contains a safety lock
mounted therewith and a disk-like element, the disk-like element being
mounted for rotation in response to the drive means, and being provided
on one side thereof with means for disengaging the safety lock for releas-
ing the hook-shaped member for counterclockwise movement.
By a variation thereof, the disk-like element is provided with
a pin means on the other side thereof and the hook-shsaped member is pro-
vided with a connecting arm which is adapted to engage and disengage with
the pin means in response to the rotation of the disk-like element, the
hook-shaped member moving from a closed to an open position during such
movement.
By another variation thereof, an additional switch means is
operatively associated with the gear assembly and is mounted for providing
continual rotation of the disk-like element, thereby releasing the safety
lock to a position for locking the hook-shaped member when such member is
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'~ manually clos~ed.
B~ ~lother'variant, spring means are operatively associated with
the hook-shaped member'for holding the'h~ok-shaped'member in either an
open or closed posit~on.
By another aspect of this invention, a remote-controlled safety
hook assen~ly is provided which comprises': a supporting frame; a hook-
shaped member rotatably disposed within the supporting frame; a lug means
attached to ;the hook-shaped member, two shackle means suspended from the
supporting frame; drive means disposed in the supporting frame; a gear
assembly operatively connected with the drive means and the hook-shaped
member for automatically swinging the hook-shaped member from a closed
posi~ionto an open position in response to specified control signals; and
a load safety switch disposed for engagement with the lug means so that
when the hook-shaped member is placed under load, the lug means engages
the load safety switch, thereby eliminating all power to the hook-shaped
member.
By a variant thereof, the shackle means are spring biased.
By a variation thereof, the spring-biased shackle means have a
substantially U-shaped configuration with the free ends of the shackle
means being rotatably connected to the supporting frame.
By a further variant, a power supply means is disposed in the
supporting frame.
By another variant, the shackle means are spring biased and
extend laterally with respect to the hook-shaped member, the shackle means
being rotatably suspended from the supporting frame.
By yet another variant, the gear assembly contains a safety lock
mounted therewith and a disk-like element, the disk-like element being
mounted for rotation in response to the drive means, and being provided
on one side thereof with means for disengaging the safety lock for releas- '
ing the safety hook for counterclockwise movement.
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8891
`~ By a variation thereof, the sa~ety switch ~s attached to the
sa~ety l~ck for engagement with the lug mean~.
By another variant, the disk-like element is provided with a
pin means on the other side thereof and the hook-shaped member is provided
with a connecting arm which is adapted to engage and disengage with the
pin means in response to the rotation of the disk-like element, the hook-
shaped member moving from a closed to an open position during such move-
ment.
- By yet another variant, an additional switch means is opera-
tively associated with the gear assembly and is mounted for providing
continual rotation of the disk-like element, thereby releasing the safety
lock to a position for locking the hook-shaped member when the member is
manually closed.
By another variant, spring means are operatively associated
with the hook-shaped member for holding the hook-shaped member in either
an open or closed position.
In the accompanying drawings, -
Figure 1 is a front view of the radio-controlled safety hook of
one aspect of the present invention;
Figure la shows the embodiment of one aspect of the present
invention whereln the safety hook obtains its electrical power from a
ground source;
Figure 2 is a rear view of the radio-controlled safety hook of
an aspect of the present invention;
Figure 3 is a right side view of the radio-controlled safety hook
of an aspect of the present invention;
Figure 4 is a left side view of the radio-controlled safety hook
of an aspect of the present invention;
Figures 5 - 8 show the construction and operation of the master
gear assembly and hook assembly of an aspect of the present invention;
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7~139~
Figure 9 shows the operation oE the pick-up switch diaposed
behind t~e motor;
Figure 10 is a bottom vie~ of a disk-like member which forms
part of the master gear assembly;
Figure 11 is a detailed profile view of the master gear assembly
used in an aspect of the present invention;
Figure 12 shows a single chocker arrangement wherein the entire
weight of the load is borne by a single chocker extending from the hook to
the load;
Figure 13 shows a double chocker arrangement wherein the load is
cradled by the chockers and the weight of the load is shared by the
chockers extending from the hook and the chockers extending from the large
spring-biased shackles;
Figure 14 shows an embodiment similar to Figure 12 wherein a
double shackle arrangement is utilized in place of a single shackle
arrangement;
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Flgure lS shows a further embodiment of the design of the large
spring-biased shackles used in the safety hook of another aspect of the
present invention;
Figure 16 shows the large spring-biased shackles in a non-load
position;
~ Figure 17 shows the large spring-biased shackles of the present
invention in a load position;
Figures 18 and 20 show the cooperation of the hook-shaped member
and a closè switch? as the hook-shaped member moves from a closed to an open
position, for substantially preventing possible damage t~ the receiver and/
or the relay and/or the power supply; and
Figure 19 shows the use of a load safety switch in cooperation
with a cam attached to the top of the safety hook-shaped member for sub-
stantially preventing accidental opening of the hook-shaped member when the
hook-shaped member is under load.
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.~ 1 ~1~78~39~
Referring now to the rawl~gs, wherein i~entical reference
numerals are used throu~hout the various views to indicate `i~enti
cal elements, the apparatus of an aspect of the present invention, with par-
ticular refcrence to Figures 1-4, comprises a casing 1 includ;ng
a hood portion 2 and a base portion 3. Frame members 4 are dis-
posed bet~een the ~ase portion 3 and the hood portion 2 ~nd ex-
tend througll the hood and the base to provide overall support
for the entire unit. The portion of the frame member 4 extending
through tlle hood 2 is connected by a pin to a lifting support mem
ber 6 provi(led with an eye bolt 7. The pin 5 provi~es one-hal~
of a universal connection with the lifting support member 6 so
that the lifting support member can rotate clock~ise and counter-
clockwise about the axis of the pin 5. On the other hand, the
eye bolt 7 rotates in the hori~ontal direction, that is, perpen-
dicular to the vertical axis of the device. Thus, in operation,
the safety hcok of an aspect of the p~essnt invention can rotate fre~y in
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the horizontal plane and, in addition, can swing both clockwise
and counterclockwise in the vertical plane. This, of course,
provides great maneuverability when the safety hook of an aspect of the present
inve}ltion is under load.
The frame member 4 extending through the base portion 3 is
connected ~y a support pin 8 to a pair of large shackles g and a
hook 10. The shackles and the hook are freely movable about the
support pin 8. The shackles are spring biased, and are symmetric-
ally disposed about the hook so that in their relaxed, non-load
state, thsy are open and do not significantly interfere with accessibility to
the hook. The shackles extend through the base 3 where they are
connected to a coiled spring 11, which is tensioned so as to
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`~ 10'~889i
provide said spring bias to the shackles in their open, non-load
position. The coiled springs are in turn connected to the frame
member 4.
A battery, for example, a 12-volt battery, is utilized as
the power supply for the safety h~ok of an a~t of the present invention.
The battery is disposed in a battery box 12 which is made of a
strong metal such as steel. The battery box can be provided with
a fold-up handle 12a which can be held in an extended position
from the battery box by a pin. Thus, the battery is inserted
into the battery box and with the assistance of the fold-up handl ,
the battery box is inserted in the frame members 4 of the safety
hook and held in position in the frame members by a spring 13 ad-
vantageously fastened to the frame 4 disposed beneath the hood.
The spring 13 functions to compress and hold the battery box in
position within the frame. The bottom of the battery box is also
provided with two substantially parallel ridges which extend from
the bottom of the battery box and straddle a portion of the sup-
porting frame for holding the battery box stationary within the
frame. Alternatively, the battery can be dispensed with and in
this embodiment as shown in Fi~ure la electrical cables extend
from the safety hook to a source of electricity in the ground.
A radio receiver 15 is spring mounted to a radio receiver
frame 16 which, in turn, is secured to the support frame 4.
The radio receiver frame 16 is provided with springs 17 and 18
to cushion the radio receiver against vertical and horizontal
shock movements, respectively.
A relay 19 is similarly spring mounted to the other side of
the support frame 4. The relay 19 is attached to a plate 20
which is held in position by springs 21 which are attached to a
table 22 which is fixed to the support frame 4. An aperture 23
is provided in said table and the electrical connections for the
relay extend through said aperture for connection with the
various elements of the unit.
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~07~389~
The fram~ 4 alsP supports a motor 24, for example, a 12-Yolt
motor provided with a worm gear, whic~ is separated from the battery by
an intermediate frame mem~er 25. The motor is cradled from below in a
motor mount 4a which extends from the frame 4 and follows the curvature
of the motor. A screw clamp 26 generally extends over the top surface
of the motor and is fixed at one end to the motor mount and at the other
end thereof to a stud 27A which, în turn, is seucred to the frame 4.
Thus, by tightening the screw clamp 26, the motor is held firm between
the screw clamp on the top of the motor and the motor moun~ at the bottom
of the motor.
Figures 5-8 show the construction and operation of the master
gear assembly and the hook assembly of the safety hook of an aspect of the
present invention. In referring to Figures 5-8, it can be seen that the
motor 24 drives a master gear 27 which is mounted to the motor. A disk-
like member 28 is mounted for rotation on a cog member 29. The disk-like
member 28 is provided with a ridge 39 which extends inward toward the
master gear for engagement with a lever 31 (see Figures 9 and 11) which is
adapted to ride on the ridge 30. As the ridge 30 engages the lever 31, it
pushes said lever into contact with a pin 32 which is attached to a safety
lock 33. The safety lock 33 is, in turn, released, against the spring
action of spring member 34, free from contact with dog 35 attached to the
top portion of the hook, thereby releasing the hook for movement in the
counterclockwise direction in response to radio signals.
A spring element 36 is attached at one end to a lug 37 which is
secured to the top of the hook. At the other end, the spring element is
attached to a ball socket which in turn is secured to the frame 4. The
spring element 36 functions to hold the hook either in an open or closed
position.
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¦¦ A plate member 39 is ~o~nted on the same support pin B which~
holds and sul~ports the shackles and the hook. ~he plate member
is provided Wit}l a tooth 40 which engages the stop 41 attached to
the frame for limiting thc movemen-t of the plate member 39. The
S ~latc mcmber is provided with a peg 42 and a peg 43 wllich extend
inwardly and outwardly, respectively, from the plate mcmber 39.
Tlle peg member 42 is provided for engagement with the tooth 44
attache~ to the top of tlle hook. Tlle connecting rod 45 is at-
tached at one end to the peg 43 and is provided at the other end
witll a notch 46 which is adapted to engage Wit}l pin 47 which ex-
tcnds from the top of the disk~like member 2~. A spring 48 is
attached at one end to an extension 49 of the ccnnecting rod 45
and is attachcd at the other end to a nipple 50 extending from
the plate mcmber 39. The spring 48 holds tension on the connect-
ing rod 45 for cngagement with the pin 47. An additional spring51 is secured at one end to a pin 52 attached to the plate member
39, and at the other end to the mounting frame 53 for the master
gear. I`he spring 52 holds tension on the plate member 39 so that
when the yin 47 on tlle disk-like member 28 disengages from the
slot46 in the connecting arm45, due to the continuing rotation of
the plate, the spring pulls the plate member 39 clockwise back to
a starting position against stop 41. Thus, with the hook in the
open ~osition, the (levice is now rea~y Eor reloading. T}le stop 41
also acts to limit the extent of the opening of the llook by engag-
ing Wit}l the back o the hook. ~o facilitate disengagement of theconnecting rod 45 from the pin 47, the cog member 29 is provided
with a ring 29a which acts as a cam to disengage said connecting
rod from said pin.
When the hook opens to its maximum position by striking the
stop 41, it also, at the same time, contacts a cut-off switch 54
1078891 . ~
which cuts off all electrical power to the hook. l~hen th~ power
to the cut-off switch 54 is cut off, the switch SS is energized
and makes contact through switch arm 56 to pin 47. The electri-
cal energy supplied to pin 47 causes the disk-like element 28
to continue to rotate until the connecting rod 45 disengages
from the pin 47. At this poi,nt, the spring 51 which is attached
to plate member 39 causes said plate member to rotate clockwise.
Since the control arm is connected to the plate member, both are
returned to their initial starting positions due to the action of
the spring member. At the same time, as soon as the ridge portion
30 becomes disengaged from the lever 31, the safety lock 33 spring
back to engagement with the top portion of the hook. The safety
lock is not~ in a ready position to lock ~hen the hook is closed.
Thus, as the hook is manually closed, the safety lock rides on the
top portion of the hook until it finally engages in a locking
position with dog 35.
Element 57 is a bar attached to the safety lock, said bar be-
ing provided with a ring 58 which facilitates manually releasing
the safety lock. Thus, in the event of a malfunction in the oper-
ation o the hook, the safety lock can be manually retracted toopen the hook. The bar 57 contains a slot 59 through ~hich the
pin 32 can move during the automatic operation of the hook. The
spring 34 of the safety lock 33 is supported by a spring support
member 60 as sllown in Figure 11. Also, a keeper 61 for supporting
the key is shown in Figure 9. Figure 10 shows the underside of
the disk-like m~mber 28 provided with a ridge 30. The pin 47
which extends from the top side of the disk-like member 28 ~or
engagement with the connecting rod 45 is shown in phantom in
Figure 10.
The electrical components used in the radio-controlled safety
hook of an aspect of ~he present invention are well known in the art and do
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1078891
¦ not form part o tile prescnt invention. Basically, when it is
¦ desired to operate the safety hook, a radio frequency is trans-
I mitted to the radio receiver disposed on the supporting frame
¦ of the safety hook. The radio receiver, in turn, energi~es a
5 I relay whic}l activates the motor, thereby initiating the operation
¦ of the hook. Element 62 is an electrical clistributing block for
¦ controlling and transferring the electrical connections to various
¦ components o~ the system.
¦ The o ~ ation of the ~fety ~ k o~ an a~t of the present invention
10 ¦ will now be clescrlbed with particular reference to Figures 12^14,
¦ In Teferring to Figure 12, a choker
¦ 63 is choked around a bcaln 64 by drawing the choker through an
¦ eye 65 made in the end portion of the choker. The other end por-
¦ tion of the choker is attached to the hook by a similar eye 66.
15 ¦ A small shackle 67 is then hooked throug]l the eye 65 and also
¦ through the eye 68 of another choker 73 using a screw pin 69.
¦ The second choker is provided at its other end with another eye
¦ 70. This eye is connected to the large spring-biased shackle 9
I by a small shackle 71 provided with a fastening pin 72. As can
20 ¦ be noted in Figure 12, the choker 73 is in an untensioned state
because the entire weight of the beam or load 64 is borne by the
choker 63. ~lowever, the choker 73 provides the ~ery valuable
function of retrieving the choker 63 after it has been released
from the hook as discussed hereinbelow.
Once the load is properly shackled as shown in Figure 12, the
hook, which is spring-biased in its open position, is manually
closed. The load is then lifted to a desired location. In posi-
tioning the load, effective use i5 made of both the universal
connection and the rotational movement of the eye bolt 7. After
the load is properly positioned, two men at opposite ends of the
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load place and secure the load. Once the load is in place and the
load is off the hook, the transmitter is activated, which sends
a radio signal of speciied frequency to the radio receiver dis-
l posed on the safety hook. The radio receiver activates the relay
¦ which stcps u~ the amperage for operating the motor. Throu~h the
operation of the motor, th;e hook oycns against its spring bias
¦in the manner shown in Figures 7 and 8. The opening of the hook
releases the eye 66 of the choker from the hook Ille clloker 63
l is, in turn, threaded through its eye 65 at the other end thereof
¦and this frecs itself from the load 64. The choker 63 is then re-
¦trieved by the choker 73 because said chokers are connected to-
¦gether by the small shackles 69. This particular sequence elimi-
¦nates the necessity of a workman walking out onto the load to un-
¦hook the choker from the load. This, of course, provides a defi-
~nite safety feature of the s~fety hook of an a~t of the present invention
wllen compared to the prior art devices.
Figure 13 shows another embodiment of the choker arrangement
of anothex as ~ t of the present invention wherein a ~ouble shackle and cradle hibch
arrangement is utilized for supporting and transferring the load.
20 As shown in Figure 13, two idcntical chokers 74 containing eyes 75
at one end thereof and eyes 76 at the other end thereof are uti-
lized. The eyes 75 are attached to the hook and the eyes 76 are
attached to the smaller shackles 77 by a screw pin 78. The smalle
shackles are in turn connected to the larger spring-biased shacklec
9. In this particular embodiment3 each of the four lengths of
choker extending from the hook and the smaller shackles, respectiv~
ly, to the load carry an equal proportion of the weight of the loa( .
l~hen the load is applied to the hook, the spring shackles and the
chokers reposition themselves in the manner shown by the phantom
lines.
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Figure 14 is somewhat similar to Figure 12 in that the choker
arrangement is the same. However, Figure 14 shows the use of a
¦double choker arrangement which utilizes both of the large, spring-
biased shackles. In addition, the design of the spring-biased
shackles has been modified as shown in Figure 15 as double shackle
with a screw pin 79 being utilized fo~ connecting the eye o the
chokers directly to the spring-biased shackles.
Figures 16 and 17 show how the large shackles are spring-
biased by the coil spring 11~ Pigure 16 shows the shackles in a
non-load position, and Figure ll shows the position assumed by
the shackles under a load condition.
In a further em~odiment of an aspect of the present invention a clo,se
switch 80 which communicates directly with the recei~er and the
battery is disposed adjacent to cut-off switch 5~, as shown in
Figure 18, so that when the hoo~-shaped member swings to a full
open position, as shown in Figure 2~, it not only engages switch
54 but also engages the close switch 80 thereby cutting of all
power to the hook-shaped member The close switch 80 provides a
protection or the receiver and the relay because if the close
switch 80 is not provided, the receiver and the relay would
remain in an operative state so that if the transmitter is
operated by an operator, it would draw power from the battery and
¦could damage the recelver and/or the relay. Thus when the hook is
openJ it engages both the cut o swltch and the close switch 80
wllich cuts off power to the motor and to the transmitter,
respectively.
In still a further feature of an aspect of the present invention a load
safety switch 81 is attached to the safety lock for engagement
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with a lug 82 which is located at the top of the safety hook-shaped member and
extends therefrom. Thus when a load is attached to the hoo~-shaped member,
the hook-shaped member shifts its position from the solid line to the dot-
dash-dot line as shown in Figure 19, which causes the lug 82 to engage the
load safety switch 81 thereby cutting off all power to the receiver and the
relay through the use of the load safety switch, accidental opening of the
hook-shaped member is prevented when the hook is under load. Also, excessive
strain on the motor is substantially eliminated. When the load is released,
the hook-shaped member shifts back to its original position causing the lug
82 to be disengaged from
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