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Patent Abstract
A hand truck with a generally upright skeletal frame carried on
spaced apart wheels connected with the lower portion of the frame
incorporates a noseplate and a pallet-supporting fork structure
configured to enter a pallet. The noseplate and fork structure are
carried on the frame to be interchangeably movable to and from vertically
spaced operative positions projecting forwardly at generally right
angles to the lower end of the frame and removed stowed positions
generally vertically adjacent the frame.
Patent Claims
I claim:
1. In a versatile hand truck comprising a generally upright skeletal
frame having laterally spaced and connected side rails with front
and rear faces and laterally inner and outer side faces, the frame
having an upper handle surface and being carried on spaced apart
wheels connected with the lower portion of the frame, the improvement
wherein: a. a noseplate and a pallet-supporting blade structure
configured to enter a pallet are carried on said frame to be interchangeably
movable to and from vertically spaced operative positions projecting
forwardly from the lower end of said frame at generally right angles
thereto and removed inoperative stowed positions generally vertically
adjacent said frame; said supporting blade structure in operative
position extending forwardly at a spaced distance above the forwardly
extending operative position of said noseplate.
2. The hand truck of claim 1 wherein said noseplate and blade structure
are each swingably carried to swing from said operative position
to lie alongside said frame.
3. The hand truck of claim 2 wherein one of said noseplate and
blade structure is mounted to slide upwardly on said frame to a
raised position upward of the upward swing path of the other.
4. The hand truck of claim 2 wherein said blade structure comprises
a fork device with a rear end having a pivotal axis disposing it
in operative position vertically above said operative position of
said noseplate.
5. The hand truck of claim 3 wherein said one of said noseplate
and blade structure is the noseplate.
6. The hand truck of claim 5 wherein laterally spaced slide members
pivotally mount said noseplate and said side rails have track surfaces
receiving said slide members for up and down sliding movement, and
wherein latch mechanism carried on said frame is operable to hold
said noseplate in said raised position.
7. The hand truck of claim 6 wherein said fork device is of a reduced
lateral width relative to said noseplate to pass swingably between
said side rails, said side rails mounting plates on their laterally
outer faces which have portions projecting rearwardly from said
side rails, said portions of said plates having mechanism pivotally
mounting said fork devices for swinging movement about an axis positioned
rearwardly of and above said pivotal axis of said noseplate.
8. The hand truck of claim 6 wherein said frame is metallic and
said slide members and track incorporate synthetic plastic slide
surfaces providing less functional resistance to sliding movement.
9. The hand truck of claim 6 wherein said latch mechanism comprises
a hook with a shank pivotally mounted on one of said side rails
above said track surfaces and with an upturned hook end, said noseplate
having an opening positioned so as to be interengaged with said
hook end when said noseplate is swung vertically to substantially
engage said front faces of said side rails.
10. The hand truck of claim 1 wherein said one of said nose plate
and blade structure is said blade structure and said blade structure
includes a pivotal mount having a front support end swingable upwardly
from a lowered position when said blade structure is in said operative
position to a remote position rearward of said front faces of said
frame side rails and a blade device pivotally mounted on said front
end of said pivotal mount to gravity fold downwardly to a removed
position generally vertically adjacent said side rails when said
mount reaches said stowed position.
11. The hand truck of claim 10 wherein interacting latch mechanism
on said rear end of said blade device and said frame side rails
is engageble when said blade device is returned upwardly from said
removed position to said forwardly extending position and said mount
is returned from said remote position to said lowered position.
12. The hand truck of claim 11 wherein initial upward pivoting
movement of said blade device disengages said latch mechanism so
that said mount can swing upwardly and said blade device downwardly.
13. The hand truck of claim 10 wherein said mount comprises an
angular bell-crank structure having pivot arm structure with ends
pivoted to said frame rearward of said side rails and laterally
inward thereof, and a blade device mounting arm structure extending
angularly thereto and having blade device mounting ends with pivot
mechanism thereon.
14. The hand truck of claim 1 wherein said one of said noseplate
and blade structure is said blade structure and said blade structure
is swingably mounted to move from said operative position to a position
between said side rails constituting said stowed position.
15. The hand truck of claim 14 wherein said side rails carry brackets
on their side faces for mounting a pivot shaft which extends between
said brackets rearwardly of said side rails and said blade structure
includes a bell-crank mount having arms pivotally mounted by said
shaft and having ends extended outwardly therefrom, said mount also
including a support extending angularly from said ends of said arms
with outer ends having pivot mechanism thereon, said blade structure
comprising forks pivotally carried on said outer ends of said mount
support, and releasable mechanism for locking said forks in a position
extending generally perpendicularly to said mount support.
16. The hand truck of claim 15 wherein said releasable mechanism
comprises rearwardly extending hooks on said forks and latch bars
fixed on said inner faces of said side rails under which said hooks
engage to prevent downward swinging of said forks while permitting
delatching swinging of said forks and mount.
17. A versatile hand truck comprising: a. a generally vertical
frame having laterally spaced and connected side rails with front
and rear faces and laterally inner and outer faces, the frame having
an upper handle surface and being carried on spaced apart wheels
disposed rearwardly of said side rails and connected with the lower
portion of the frame; b. a nose plate extending in operative position
generally forwardly from said lower end of said frame generally
perpendicularly thereto; c. a pallet support blade structure configured
to be engaged under a pallet support surface having an operative
position extending generally forwardly from said lower end of said
frame a spaced distance above said operative position of said nose
plate; and d. mechanism mounting said blade structure for swinging
movement upwardly while permitting said blade structure to fold
downwardly to lie vertically alongside said side rails.
18. The hand truck of claim 17 wherein said nose plate is pivotally
mounted on said side rails to be swingable to a stowed position
against said side rail front faces, and said mechanism mounting
said blade structure carries a pivot device permitting said blade
device to fold down against said stowed nose plate.
19. The hand truck of claim 18 wherein latch mechanism is engageable
to hold said nose plate and said blade structure interchangeably
in operative position.
20. The hand truck of claim 17 wherein said mechanism mounting
said blade structure comprises a bell crank pivotally carried at
one end by said frame and pivotally carrying said blade structure
at the other.
21. A method of operating a hand truck comprising a generally upright
frame having laterally connected side rails, with front and rear
faces and laterally inner and outer side faces, carried on spaced
apart wheels rearward of the lower end of the frame, the hand truck
further having a nose plate connected to the lower end of the frame
to move from a stowed position generally alongside the frame to
an operative position extending generally perpendicularly to the
frame, the hand truck further having a pallet supporting fork structure
mounted to move from a stowed position alongside said side rails
to an operating position generally extending forwardly perpendicularly
to said frame and spaced above said operative position of the nose
plate; comprising: a. with the fork structure in operative position
and the nose plate in stowed position, moving the fork structure
to stowed position; and b. then moving the nose plate to operative
position.
22. A method of constructing a hand truck which is comprised of
a generally upright frame, having laterally connected side rails
with front and rear faces and laterally inner and outer side faces,
carried on spaced apart wheels rearward of the lower end of the
frame, comprising: a. pivotally connecting a nose plate to the lower
end of the frame to move from a stowed position generally vertically
alongside the frame to an operative position extending generally
perpendicularly forwardly from the frame; and b. connecting a pallet
supporting fork structure to said frame to move from a stowed position
extending downwardly alongside said side rails to an operating position
generally extending forwardly perpendicularly to said frame and
spaced above said operative position of the nose plate.
23. The method of construction of claim 22 comprising pivotally
mounting said fork structure on the front end of a bell-crank device
which is swingably carried on said frame to swing upwardly when
said fork structure is to be moved to said stowed position while
said fork structure jackknifes downwardly to a position between
said side rails.
24. The method of construction of claim 22 comprising providing
latching members to extend rearwardly from said fork structure and
providing vertically elongate openings in said nose plate to pass
said latching members when said nose plate is in said stowed position
against said front faces of said side rails and said fork structure
is moved to said operative position.
25. A hand truck comprising: a. a generally vertical frame having
laterally spaced and connected side rails with front and rear faces
and laterally inner and outer faces, the frame having an upper handle
surface and being carried on spaced apart wheels disposed rearwardly
of said side rails and connected with the lower portion of the frame;
b. a pallet support blade structure configured to be engaged under
a pallet support surface having an operative position extending
generally forwardly from said lower end of said frame; and c. mechanism
mounting said blade structure for swinging movement upwardly from
said operative position while permitting said blade structure to
fold downwardly to lie vertically alongside said side rails.
Patent Description
BACKGROUND OF THE INVENTION
[0001] This application claims the priority of U.S. provisional
application Ser. No. 60/209,933 filed Jun. 7, 2000. The invention
relates to certain new and useful improvements in two-wheel hand
trucks and particularly hand trucks of the type disclosed in the
present assignee's U.S. Pat. No. 4,762,333, although not limited
to such hand trucks.
[0002] Hand trucks of the type disclosed in the patent are useful
when the loads being transported have a wide range of centers of
gravity such as, for example, cases of soft drinks and beer supported
on pallets, and kegs or barrels. As is well known, pallets are often
used for supporting such cases and typically have an upper surface
spaced above the floor on which the product loads are preformed
according to designated orders. The pallets then must be transported
from a warehouse or other processing facility to a delivery vehicle,
and then on to the place of business of the retail customer.
[0003] The hand truck to be described includes pallet accommodating
forks which can be inserted under the load support surface of the
pallet. When other products, which do not readily lend themselves
to being carried by forks, such as, for example, kegs or narrow
gauge cartons are to be carried, the forks can be swung up to an
out-of-the-way stowed position and a nose plate, which has been
stowed in a raised position, can be moved into product supporting
position.
[0004] While it is contemplated that the present invention may
find use with other types of hand trucks, it is believed that the
hand truck described in the patent mentioned, which has a manipulatable
wheel structure, which can move from a first position adjacent the
lower end of the frame for handling loads with a relatively low
center of gravity to a second rearwardly removed position for handling
loads with a relatively higher center of gravity, is particularly
suited to the tasks described. This design of hand truck is inherently
balanced when in operation with the wheel structure in either of
the positions mentioned, however, the invention is also applicable
to a hand truck whose wheel supporting structure is fixed to the
main frame and has only one position.
SUMMARY OF THE INVENTION
[0005] The present invention provides a versatile hand truck in
which a pallet supporting blade device or fork structure and a nose
plate may be alternatively and optionally used as the load carrying
surface. One of the fork and nose plate structures is pivotally
mounted to the lower end of the hand truck frame to be swung upwardly
from a position substantially at right angles to the frame to a
position rearwardly of the front of the frame. The other of the
fork and nose plate structures in one version of the invention may
be mounted for both pivotal and upward sliding movement along the
frame to a remote storage position out of the path of swinging movement
of the first mentioned support member. In another version of the
invention, the fork member is mounted for swinging movement from
a stowed position generally between the side rails of the frame
to an operative position extending forwardly above the operative
position of extension of the noseplate.
[0006] Other objects and advantages of the invention will be apparent
by reference to the following specification and to the drawings.
THE DRAWINGS
[0007] The presently preferred embodiment of the invention is disclosed
in the following description and in the accompanying drawings, wherein:
[0008] FIG. 1 is a fragmentary, schematic side elevational view
of a hand truck with the forks shown in operative pallet carrying
position and the nose plate in a raised stored position;
[0009] FIG. 2 is a similar schematic side elevational view with
the nose plate shown in operative position and the fork structure
shown moved to an inoperative stored position;
[0010] FIG. 3 is a side elevational view of the hand truck in an
upright position ready for the forks to be extended below a pallet
product support surface, the chain lines indicating other positions
of the forks and the nose plate being shown in stowed position in
solid lines and in operative position in broken lines;
[0011] FIG. 4 is a schematic front elevational view with the nose
plate in down position and the forks in raised position, the stowed
position of the nose plate being indicated in broken lines;
[0012] FIG. 5 is a schematic top fragmentary plan view showing
a typical pallet and showing the forks in chain lines as extended
in under the top surface of the pallet;
[0013] FIG. 6 is a schematic fragmentary sectional plan view on
a reduced scale illustrating the manner in which the nose plate
is held in the raised inoperative position;
[0014] FIG. 7 is a fragmentary schematic side elevational view
of the hand truck frame with the nose plate in down position, the
forks being omitted from the view in the interest of clarity and
the spread position of the wheels being indicated in chain lines;
[0015] FIG. 8 is an enlarged schematic fragmentary sectional side
elevational view of a portion of the lower end of the hand truck
frame only, illustrating several positions of the nose plate, the
forks again being omitted;
[0016] FIG. 9 is a schematic fragmentary front elevational view
thereof;
[0017] FIG. 10 is a schematic fragmentary top plan view of a portion
thereof;
[0018] FIG. 11 is a considerably enlarged view of the mechanism
within circle 11 on FIG. 10;
[0019] FIG. 12 is a partly sectional fragmentary side elevational
view of another embodiment, the fork blades being shown in operative
position and the nose plate in stowed position;
[0020] FIG. 13 is a similar view with the fork blades in stowed
position and the nose plate in operative position;
[0021] FIG. 14 is a schematic top plan view with the fork blades
in operative position shown supporting a pallet which is illustrated
in chain lines;
[0022] FIG. 15 is a schematic fragmentary sectional side elevational
view with the fork blades being shown in the process of moving to
stowed position;
[0023] FIG. 16 is a fragmentary perspective front elevational view
illustrating the releasable latching mechanism for holding the nose
plate in operative position; and
[0024] FIG. 17 is a fragmentary perspective rear elevational view
illustrating latching mechanism for releasably holding the fork
blades in operative position.
DETAILED DESCRIPTION OF THE DRAWINGS
[0025] Referring now more particularly to the accompanying drawings,
FIGS. 1-11, the hand truck illustrated is of the type disclosed
in U.S. Pat. No. 4,762,333 which I incorporate herein by reference.
It comprises rubber-tired wheels 10, rotatably mounted on a dead
axle 11. Side brackets, generally designated 12, and fixed to dead
axle 11, extend forwardly from the axle 11 toward a generally rectangular
open hand truck frame, generally designated F. The skeletal frame
F has parallel vertical side rails 14, which may be formed of extruded
aluminum in a predetermined configuration. Handles such as shown
in the aforementioned patent or a composite handle may be fixed
to the upper ends of the side rails 14 which are connected by vertically
spaced spanning braces in the usual manner. In plan, the braces
may be curvilinear in configuration as shown at 16 in FIG. 5 to
partially embrace the curvilinear surface of a keg or barrel.
[0026] Provided to pivotally connect the brackets 12 to the frame
side rails 14 are mount plates 18 which may have key portions 18a
received in the usual exterior vertical grooves 14a (FIG. 6) provided
in the exterior side faces of the channel-shaped rails 14. Plates
18 may be mounted in position by screws or bolts 20 at a level spaced
vertically from the lower end of the frame F vertically above the
axle 11 in either illustrated position of the wheels 10. At a spaced
distance rearwardly of the side rails 14, each mount plate 18 carries
an end of a fixed shaft 19 which extends between the plates 18.
While not specifically shown, the opening 12a in each bracket 12
may receive a tubular sleeve which is received on the shaft 19 and
can pivot with respect to it, the brackets 12 being welded or otherwise
suitably affixed to the ends of the sleeve. A further description
of the two different positions of the wheels 10 and of the gas cylinders
26 which pivotally connect to ears 27 on each side rail 14 to releasably
lock the brackets 12 in each of the positions, is unnecessary in
view of the explanation provided in the aforementioned U.S. Pat.
No. 4,762,333.
[0027] As particularly shown in FIGS. 1-11, the fork structure,
generally designated FS, includes a generally U-shaped mounting
bracket 28 (FIG. 4) which has end parts 28a secured to the lower
end of each rail 14 by bolts or fasteners 29, and includes a frame
spanning portion 30. As FIGS. 10 and 11 particularly indicate, the
portions 28 of the bracket carry fasteners 31 mounting members 32
from which protrude trunnions 33. Tubular sleeves 34, to which fork
legs 35 are fixed, have end parts 34a receiving the trunnions 33,
and interposed between the sleeves 34 and members 32 are spring
washers 36 which frictionally resist free rotation of the sleeves
34 on trunnions 33.
[0028] As FIGS. 1 and 3 in particular well illustrate, the forks
35 have perpendicularly extending backer walls 35a which extend
vertically when the forks are in the operative lifting position
to engage and brace against the rear faces of side rails 14. As
FIG. 3 indicates, the forks 35 can be swung upwardly to the stowed
inoperative position shown in diagrammatic lines in FIG. 3 and are
shown in this stowed position in FIG. 4. FIG. 5 shows the position
of the forks when they are moved forwardly to engage under the raised
load support surface 38 of a typical pallet P having dependent members
L supported on the ground or other surface G.
[0029] Also carried by the hand truck frame F is a nose or nose
plate, generally designated 39, which is shown in several positions
in FIG. 8 and in stowed position in FIGS. 1 and 3. The side rails
14 are generally channel-shaped in cross-section to provide interiorly
facing recesses 14b, as shown particularly in FIGS. 10 and 11, and
integrally provided within the recesses 14b are elongate vertical
guide members 40 which may bolt in place as at 41. The guides are
preferably constructed of a high molecular weight plastic material
which has a slick surface. Provided to slide vertically within the
slide guides 40 at each side of the hand truck are laterally protrudent
slide members 42 which may be fabricated of the same plastic material
and are apertured as at 43 so that they may slide upwardly and downwardly
in guides 40 without contacting the heads of bolts 41. At their
inner ends, the stems 44 of the slides 42 are provided with openings
45 to receive trunnion pins 46 which are provided in side plates
47 fixed on plates 48 which are attached by means of members 49
to the load support plates 39a of the nose plates 39. Also connected
to slides 42, as by bolts 42a, is a back plate 42b which moves with
slides 42.
[0030] Spring washers, such as beveled washers, i.e., Belleville
washers or the like, are shown at 50 and 51 as operating to frictionally
resist turning movement of the trunnions 46 to thereby tend to maintain
the nose plate 39 in either the operable swung down position in
which it is shown in FIG. 8 or the vertical stowed position in which
it is shown in FIGS. 1 and 3. In FIG. 8, the nose plate 39 is shown
in solid lines in operative position and then in broken line positions
as it is swinging to the vertical position, ready to be moved in
vertical translation upwardly to a position above the forks 35 to
the stowed position shown in FIG. 1.
[0031] As shown particularly in FIGS. 4 and 6, hook members or
latch pawls 52, which have upturned hook ends 53, may be pivoted
to the side rails as at 54 and, when the nose plates 39 are in the
vertical stowed position, as shown in FIG. 4, the ends 53 extend
through slots 55 provided through the nose plate 39 to latch the
nose plate 39 in stowed position. The weight of the nose plate bearing
down on the pawl members 52 supports the nose plate in the stowed
position because the plates 39 engage against the front wall surfaces
of the side rails 14 and prevent the members 52 from pivoting rearwardly.
THE OPERATION
[0032] It is to be understood that forks 35 are moved under the
support surface 38 of the pallet P by simply moving the hand truck
forwardly when the hand truck is in the FIG. 3 position. When the
forks 35 are engaged under the pallet surface 38, the hand truck
is tipped back to the FIG. 1 position for transport. With high center
of gravity loads, the wheels 10 can be adjustably moved in the manner
disclosed in U.S. Pat. No. 4,762,333 to the spread position. The
forks 35 are prevented by way of engagement of the parts 35a and
14 from swinging below the horizontal position in which they are
shown in FIG. 3. In this position of its parts, the hand truck has
its nose plate 39 in the upper stowed position disposed flatwisely
against the front faces of side rails 14. When it is desired to
transport other products, such as kegs or drums, fork assemblies
35 are swung to the upper stowed position shown in FIGS. 3 and FIG.
9, and pawls 52 are manually swung rearwardly to disengage from
the nose plate assembly 39. The nose plate is then permitted to
move downwardly with slides 42 along the front faces of side rails
14 until it reaches the vertical position shown in FIG. 8, whence
it may be swung downwardly to the operative horizontal position
shown in FIGS. 2 and 8. The nose plate 39 is then moved under the
product to be transported. If the load is a high center of gravity
load, the wheels 10 may be moved to the spread position disclosed
in U.S. Pat. No. 4,762,333.
DESCRIPTION OF ANOTHER EMBODIMENT
[0033] A further embodiment is disclosed in FIGS. 12-17 in which
the same numerals will be used to identify the same or very similar
components for the sake of clarity.
[0034] As previously, the hand truck comprises rubber-tired wheels
10, rotatably mounted on a dead axle 11. Side brackets 12 fixed
to the dead axle 11 extend forwardly from the axle 11 toward a generally
rectangular skeletal truck frame, generally designated F. The frame
F has parallel generally vertical side rails 14 with a handle H
fixed to the upper ends of the side rails 14, which may be connected
by laterally extending spanning braces 16.
[0035] Provided to pivotally connect the axle brackets 12 to the
frame side rails 14 are mount plates 18 which may have key portions
received in the exterior vertical channels provided in the exterior
side faces of the channel-shaped rails 14 in the usual manner. The
plates 18 may be mounted in position by suitable bolts.
[0036] Rearwardly of the side rails 14, each bracket 12 carries
an end of a fixed shaft 19, which extends between the plates 18.
While not particularly shown, the opening in each bracket 12 may
receive a tubular sleeve, which is received on the shaft 19 and
can pivot with respect to it.
[0037] As previously, the wheels 10 have two different positions
and the gas cylinders 26, which pivotally connect to brackets 27
on each side rail 14, releasably lock the brackets 12 in each of
the positions as previously. The piston rods 26a of cylinders 26
pivotally connect to the brackets 12 at 26b, and the cylinders 26
pivotally connect to bracket 27 at 27b. Since the mechanism for
moving the wheels 10 to the two different positions forms no part
of the present invention, these components will not be further described.
Any further explanation of the gas cylinders 26 and how they are
operable in either of the two positions which the wheels 10 may
assume, as disclosed in U.S. Pat. No. 4,762,333, is unnecessary,
since this structure forms no part of the present invention.
[0038] As particularly shown in FIGS. 12-17, the fork or blade
structure in the second embodiment, generally designated FS, includes
fork legs 35 connected by a spanning brace 56 which compositely
may also be referenced as a blade device for engaging under the
top support surface of the pallet P in the normal manner. At their
rear ends, the fork or blade members 35 are connected by a shaft
58 which is pivotally mounted by a bell-crank like fork or blade
structure mount, generally designated 59. The pivot shaft 58 is
received within journals carried on the bell-crank arms 59a. The
opposite end of bell-crank 59, comprises legs 59b extending at right
angles to the legs 59a which are pivotally received on the shaft
19.
[0039] The nose plate 39 is pivotally mounted to swing upwardly
to a position in engagement with the front faces of the side rails
14, as indicated in FIG. 12, for example. Nose plate 39 is pivotally
mounted on the lower ends of the side rails 14 on pivots 60 to swing
from the position shown in FIG. 13, in which the nose plate back
39a lies vertically adjacent the side rails 14 to the position shown
in FIG. 12 in which it lies horizontally beneath the side rails
14.
[0040] On the lower end of each of the rails 14 is a latching mechanism
for both the nose plate 39 and the fork structure FS. This latching
mechanism, generally designated LM, includes an inwardly facing
channel-shaped plate 61 secured to the side rails by bolts 61a which
carries a locking rod, designated 62. The ends of the rod 62 may
be carried in vertically elongate slots 62a in plate 61.
[0041] Angle brackets, generally designated 63, and secured by
bolts 64 to the nose plate back member 39a are upwardly slotted
as at 63 to receive the locking rod 62, and it is only when the
rod 62 is moved upwardly of brackets 63 in the slots 62a that nose
plate 39 is free to pivot about its pivots 60 and swing up into
vertical engagement with the side rails 14. When the nose plate
39 is swung downwardly, once again, to a horizontal operative position,
the rod 62, when released, falls by gravity into the slots 63 to
positively restrain movement of the nose plate 39.
[0042] As FIGS. 16 and 17 indicates, the front side wall 61a of
the plate 61 is elongately slotted as at 65 and the nose plate 39
is elongately slotted as at 66. Provided to extend from the rear
ends of fork blades 35 are upwardly disposed L-shaped hook members
67 which, when the fork blades 35 swing down to the generally horizontal
operative position pass through the slots 66 in the swung-up nose
plate 39 and engage under the marginal wall of the locking slot
65, as shown in FIG. 17, so that hook wall 67a is disposed rearwardly
of and embraces the side wall 61a of the plate 61. This latching
occurs automatically when the fork leg structure FS swings down
to the generally horizontally disposed operating position. To unlatch
the blade or fork structure FS, it is first necessary to lift the
front end of a fork leg 35 to pivot the latch hooks 67 down to a
position to clear wall 61 as the fork structure FS is moved forwardly
and upwardly.
[0043] It is the brackets 63 secured to the nose plate 39 which
mount the nose plate pivot pins 60, there being spring or Belleville
washers mounted on the pins 60 between the bracket walls 63 and
the side rails 14 to provide initial resistance to upward pivoting
of the nose plate 39.
THE OPERATION OF THE SECOND EMBODIMENT
[0044] As FIG. 13 indicates, the hand truck may be operated in
the normal manner with the nose plate 39 locked in position by locking
rod 62. In FIG. 13, the forks 35 are shown folded downwardly about
pin 58 to their stowed position, generally within the lateral footprint
of the side rails 14 so that they do not interfere with the transport
of desired products lying against the side rails 14. When a pallet
P is to be lifted, however, the shorter nose plate 39, which is
disposed at the lower ends of rails 14 in operative position, will
not be suited to the task. To interchangeably move the fork structure
FS to operating position, it is necessary to first lift the nose
plate locking rod 62 out of slots 63 and the nose plate 39 can then
be swung up to the vertical position shown in FIG. 17. When this
is accomplished, the fork legs 35 can be grasped and moved forwardly
to start the pivoting of the bell-crank structure 59 about shaft
19. Once the portions 59a of the bell-crank 59 reach a horizontal
position and move lower, the off-set weight of the rear ends of
the fork members 35 swings the pivot shaft 58 about the mount 59
to the horizontal position, and when portions 59b reach vertical
position, the lock members 67 have swung under the ledge provided
by walls 61 and hook behind them. With the fork structure FS in
locked position, the fork members 39 may enter a pallet and lift
it and transport it in the usual manner of a fork truck. The fork
structure is operative when the pallets comprise simply a top wall
supported on legs, or when the pallets have vertically spaced upper
and lower walls between which the forks 35 can be inserted.
[0045] The manner of restoring the fork structure FS to stowed
position by initially lifting the forks 35 and swinging the bell-crank
59 rearwardly has been described and will not be repeated. The nose
plate 39 may, as earlier described, be swung down to operative position
when the locking rod 62 is lifted and then permitted to fall into
the slots 63 when the nose plate reaches operative position. Plainly,
existing hand trucks in the field may be readily retrofitted with
the noseplate and fork structure components.
[0046] The construction disclosed provides a versatility permitting
use of either the forks or the nose plate interchangeably with the
wheels in either position of adjustment, or with a hand truck having
simply wheels which have no positions of adjustment.
[0047] It is to be understood that other embodiments of the invention
which accomplish the same function are incorporated herein within
the scope of the following patent claims.
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