Removable hoist system

A removable hoist system for a doorway of a van which comprises, when in position, a post vertically mounted in the doorway and an arm having one end secured to the post. The arm during operation extends horizontally from the post and a lift mechanism is secured to the other end of the arm, for lifting or lower objects with respect to the van. A lower plate is secured to the floor of the van where the post is mounted and an aperture centrally positioned in the plate, and an upper plate is secured to a frame portion of the van in the upper part of the doorway, vertically above the lower plate with an aperture centrally positioned in this upper plate. Pins removably received in the aperture of the plates to hold the post in vertical position during operation outwardly extend from the ends of the post. The post is of a length so that when it is in position with its pins in the apertures there is sufficient clearance at the top to permit lifting of the post so that the lower pin is clear of the aperture for removal of the post. The plates have sufficient load bearing strength when secured in position in the van to withstand a predetermined weight of object when lifted or lowered by the lift mechanism.

The present invention relates to a removable hoist system for a doorway of 
a light duty van. 
BACKGROUND OF THE INVENTION 
There is presently a need for a device for lightweight vans, particularly 
when used for commercial purposes, which will facilitate lifting of heavy 
objects into the van from the outside, or lowering of such objects to the 
ground from within the van. At the present time, such objects are 
generally manually raised and lowered. 
There has been a need for a mechanical means to assist the lifting and 
lowering of such heavy objects in such service vans. Truck mounted lifting 
cranes such as those described and illustrated for example in Coates et al 
U.S. Pat. No. 2,862,628 have not been suitable for adaption to service 
vans since they require special brackets for mounting at both top and 
bottom. Permanently mounted track hoists are described and illustrated for 
example in Adams U.S. Pat. No. 2,512,988 issued Jun. 27, 1950 and Reed 
U.S. Pat. No. 2,565,091 issued Aug. 21, 1951. An externally mounted truck 
hoist is described and illustrated in U.S. Pat. No. 3,578,179 of Fujioka 
issued May 11, 1971. Again that construction requires special brackets at 
top and bottom making it effectively a permanently mounted structure. 
It is an object of the present invention to provide a sturdy, lightweight 
hoist system for a light duty service van, whereby a hoist may be easily 
installed in and removed from the doorway of the van, to thereby permit 
easier handling of heavy objects with respect to the van. 
SUMMARY OF THE INVENTION 
In accordance with the present invention there is provided a removable 
hoist system for a doorway of a van which comprises, a post to be 
vertically mounted in the doorway and an arm having one end secured to the 
post. The arm during operation extends horizontally from the post and a 
lift means is secured to the other end of the arm, for lifting or lower 
objects with respect to the van. A lower plate is secured to the floor of 
the van where the post is mounted and an aperture centrally positioned in 
the plate, and an upper plate is secured to a frame portion of the van in 
the upper part of the doorway, vertically above the lower plate with an 
aperture centrally positioned in this upper plate. Longitudinally 
extending at opposite ends of the post are pins removably received in the 
apertures of the plates to hold the post in vertical position during 
operation. The post is of a length so that when it is in position with its 
pins in the apertures there is sufficient clearance at the top to permit 
lifting of the post so that the lower pin is clear of the aperture for 
removal of the post. The plates have sufficient load bearing strength when 
secured in position in the van to withstand a predetermined weight of 
object when lifted or lowered by the lift means. 
In a preferred embodiment, the post and arm are collapsible. In particular 
the arm is pivotally secured to the post near its top. A brace member 
having two ends is pivotally secured at one end near the bottom of the 
post with the other end being releasably securable to the arm to support 
the arm horizontally. 
The hoist system according to the present invention is simple to install 
and operate. The plates when mounted in the doorway of the van so as not 
to obstruct the closing of the van doors, require no latch pins or special 
brackets for mounting of the posts in vertical orientation or removal 
thereof. To remove the hoist itself, the post is simply lifted to clear 
the lower pin from its aperture, pulled back at the bottom and lowered to 
clear the upper pin from its aperture, for removal in a matter of seconds, 
without tools pins or latches. No special brackets are required at the top 
of the post--only a small hole must be made in the frame, in alignment 
with the aperture in the upper plate. No alterations at all are required 
in the bottom of the truck, other than to secure of the plate to the 
bottom.

DETAILED DESCRIPTION OF THE INVENTION 
In the drawings, similar features have been given similar reference 
numerals. 
Turning to FIG. 1 there is illustrated a hoist system 2 mounted on a light 
duty service van 1. Hoist system 2 comprises a post or mast 6 which is 
preferably mounted in the rear entrance doorway of a van so that doors 8 
will not close when post 6 is in position, but will close when post 6 is 
removed from position, in a manner which will be explained in more detail 
hereinafter. This is designed as a safety feature. 
Post 6 is provided with bottom pin 10 and top pin 12 (FIG. 3) for removably 
mounting the post with respect to the van. In this regard, a bottom plate 
14 is fastened, by bolts or other appropriate fasteners, to floor 16 in 
the rear doorway of the van 4 as illustrated. An aperture 18 is centered 
within bottom plate 14 as illustrated, for removably receiving bottom pin 
10 of post 6. Above the doorway and secured to the door frame 20 of van 4 
by means of bolts or other fastening means is a top plate 24. Aligned 
vertically above aperture 18 and centered in plate 24 is an aperture 26 to 
removably receive top pin 12 of post 6. A depression 28 is drilled into 
frame 20, aligned with aperture 26, to receive the upper portion of top 
pin 12 as illustrated in FIG. 1. 
The positioning of plates 14 and 24 in the doorway of van 4 does not 
interfere with the opening and closing of doors 8. 
Upper pin 12 is somewhat more elongated than bottom pin 10 and a clearance 
30 is provided between the top 32 of post 6 and top plate 24 to ensure 
that post 6 may be readily removed from or positioned in plates 14 and 24, 
and securely held in position by these plates when installed in position 
as illustrated in FIG. 1. To insert post 6 into position, top pin 12 is 
fully inserted in the aperture 26 of top plate 4 and depression 28 in door 
frame 20. This provides clearance at the bottom to enable bottom pin 10 to 
be moved into position and dropped into aperture 18 of bottom plate 14. 
For removal from this position, post 6 is elevated so that bottom pin 10 
is removed from and clear of bottom plate 14, enabling post 6 to be swung 
sideways, away from vertical orientation, until it is entirely clear of 
bottom plate 14 and floor 16 of the van. Top pin 12 may then be removed 
from aperture 26 and depression 28 by downward movement of post 6. 
Pivotally secured to post 6 are arm 34 and brace member 36. More 
particularly, a pair of plates 38 is secured to both sides of post 6 near 
its top, and inner end 40 of arm 34 is pivotally bolted to the plates 
through aligned apertures in the plates 38 and inner end 40 of arm 34. 
Similarly the lower end 42 of brace member 36 is bolted between spaced 
plates 44 secured to a lower portion of post 6 as illustrated. As can be 
seen in FIG. 3, the positioning of the pivot points of arm 34 with respect 
to plates 38 and brace member 36 with respect to plates 44 is such as to 
permit the arm and brace member to be collapsed into orientation parallel 
with post 6 for storage purposes. 
A pair of plates 46 are secured to either side of arm 34 in downwardly 
depending fashion, as illustrated in FIGS. 1 and 2, and provided with 
apertures 48 (FIG. 3) which are aligned with aperture 50 in the free end 
of brace member 36 so that a pin 52 may be removably received in these 
apertures, when aligned, to maintain and support arm 34 in horizontal 
position when hoist system 2 is operational. When pin 52 is removed, arm 
34 and brace member 36 may be pivoted into collapsed position as 
illustrated in FIG. 3, for storage. Brace member 36, in this collapsed 
position, is nested between plates 46 to provide a neat, compact 
arrangement for storage purposes. It is preferred that, in this collapsed 
position, apertures 48 be aligned with an aperture 53 in post 6 so that 
placing pin 52 through these aligned apertures will secure the arm and 
brace member in collapsed position parallel to post 6. 
Post 6, arm 34 and brace member 36 are preferably made of square or 
rectangular tubular metal stock, although any other material providing 
light weight sturdy construction may be used. 
To free end 54 of arm 34 is releasably secured a chain block 56 as 
illustrated in phantom in FIG. 1. Preferably a plate 58 is secured, to be 
in vertical orientation when hoist system 2 is operational, to the free 
end 54 of arm 34, plate 58 being provided with an aperture 60 to which 
chain block 56 may be hooked. Chain block 56 itself is preferably provided 
with a hand-operated rachet means 62, by which chain 64 may be raised or 
lowered, any appropriate object securing means 66 being provided on chain 
64. 
As previously indicated, to install the hoist or crane provided by post 6, 
arm 34 and brace member 36 in position, post 6 is simply lifted vertically 
so that top pin 12 is inserted in aperture 26 in top plate 24 and 
depression 28 in the van frame 20, and then, with bottom pin 10 aligned 
with aperture 18 in bottom plate 14, post 6 is lowered so that bottom pin 
10 is seated in aperture 18 in bottom plate 14. In this position, a 
portion of pin 12 remains seated in upper plate aperture 26. With both 
pins thus seated in the apertures of their corresponding plates, arm 34 
and brace member 36 are then unfolded from storage position until the 
apertures 48 in plates 46 are aligned with brace member aperture 50. Pin 
52 is inserted in these aligned apertures so that arm 34 is held in 
horizontal position. Chain block 56 is mounted on plate 58 and hoist 
system 2 is then operational. 
The size, shape and location of plates 14 and 24 are selected so as to 
ensure that the hoist system 2 is securely maintained in position and can 
withstand a predetermined weight of an object when lifted or lowered by 
chain block 56. These plates are positioned, as well, so that they do not 
obstruct the opening and closing of doors 8. 
It has been ascertained through testing that the hoist system 2 according 
to the present invention will lift objects of up to one-half to 
three-fourths of a ton with little or no difficulty. 
Pins 10 and 12 are preferably of circular cross-section so as to permit 
post 6 and arm 34 to pivot about an axis through these pins when post 6 is 
in operative position with respect to plates 14 and 24 (FIG. 1). 
It will be understood that no holes are required in the bottom of the 
vehicle for insertion of the bottom pin 10, as that pin is carried 
entirely by bottom plate 14. As well no special brackets are required at 
the top. The only structural modification required for the top of the 
doorway is the small depression 28 which is formed behind aperture 26 of 
top plate 24 and the holes for receiving fastening means to secure top 
plate in position. The device according to the present invention requires 
no special brackets or pins for removal or installation and is easy to 
install for use and to remove and collapse for storage. 
Thus it is apparent that there has been provided in accordance with the 
invention an improved removable hoist system for a doorway of a van that 
fully satisfies the objects, aims and advantages set forth above. While 
the invention has been described in conjunction with specific embodiments 
thereof, it is evident that many alternatives, modifications and 
variations will be apparent to those skilled in the art in light of the 
foregoing description. Accordingly, it is intended to embrace all such 
alternatives, modifications and variations as fall within the spirit and 
broad scope of the invention.