U.S. patent number 3,762,687 [Application Number 05/229,650] was granted by the patent office on 1973-10-02 for post pulling apparatus.
Invention is credited to Eugene J. De Rome, Carl J. Hengst.
United States Patent |
3,762,687 |
De Rome , et al. |
October 2, 1973 |
POST PULLING APPARATUS
Abstract
A fence post pulling apparatus is constructed of a pair of
members, each member having an aperture for receiving a post
therethrough with the end portions of the members extending
outwardly in opposite directions, and flexible means such as a
chain interconnecting the opposite end portions of the members,
whereby an upward force on the chain will cause the members to grip
the post and pull it axially upwardly, and the transverse forces
will be substantially opposed and balanced.
Inventors: |
De Rome; Eugene J. (Morton
Grove, IL), Hengst; Carl J. (Niles, IL) |
Family
ID: |
22862143 |
Appl.
No.: |
05/229,650 |
Filed: |
February 28, 1972 |
Current U.S.
Class: |
254/30;
294/92 |
Current CPC
Class: |
E04H
17/265 (20130101); B66F 19/00 (20130101); B66C
1/62 (20130101) |
Current International
Class: |
E04H
17/26 (20060101); B66C 1/62 (20060101); B66F
19/00 (20060101); B66f 003/06 (); E21b
010/02 () |
Field of
Search: |
;254/29R,30,31,132
;294/92
;24/249R,249PP,249SA,249PC,249DP,132AA,132AB,132AC,132AS |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
1,073,096 |
|
Jun 1967 |
|
GB |
|
136,784 |
|
Mar 1950 |
|
AU |
|
87,394 |
|
May 1956 |
|
NO |
|
Primary Examiner: Simpson; Othell M.
Claims
What is claimed is:
1. A fence post pulling apparatus comprising a pair of separate and
independent post gripping members, each member being apertured
adjacent one end thereof, whereby said members may be separately,
independently and sequentially placed on a post and positioned in
superposed relationship with respect to one another with their
respective other ends extending transversely outwardly in opposite
directions from the longitudinal axis of the post, and each may be
pulled to an angular position to grip the post independently of the
other, and a continuous, elongated and uniform flexible member
extending between and interconnecting said other ends of said
members and providing means for ready engagement by a hoist and for
transmission of pulling power uniformly to the two gripping members
regardless of their relative position on the post.
2. The apparatus according to claim 1 wherein said apparatus is
adapted to be used in connection with a radially flanged fence
post, said gripping members being in the form of plates with the
apertures therein corresponding to the shape of the cross sectional
profile of the post and being of such size that the members may be
slid over the post in the direction of the longitudinal axis of the
post, but said members will not rotate relative to the longitudinal
axis of the post, whereby when said flexible member is pulled
upwardly said gripping members will tilt to grip the fence
post.
3. The apparatus according to claim 1 wherein the apertures in each
of said gripping members are mirror images of one another and are
enlarged angular projections of the cross section of the post being
pulled.
Description
BACKGROUND OF THE INVENTION
This invention relates to an apparatus for pulling posts, such as
standard metal fences post which have been driven into the ground.
The apparatus is designed for use in connection with standard
lifting equipment such as a crane hoist having a cable and a wench
with a hook for engaging the post pulling apparatus.
The apparatus has particular application in the removal of standard
fence posts and is especially useful in the dismantling of snow
fences where many fence posts must be removed and efficiency is
important. Standard fence posts are usually about 7 feet in length
and are driven approximately 3 feet into the ground. Heretofore,
when removing these fence posts from the ground, it was the
practice to wrap a chain several times around the post and then
attach the chain to the hoist. This was a rather slow process
because the chain had to be wrapped securely around the post, and,
even then, there was a tendency for the chain to slip and for
workmen to be injured by the chain which was being pulled upwardly
with a substantial force in the post removal operation.
When this "wrapped chain" procedure was utilized, frequently the
post would be bent or otherwise damaged by the unequal force of the
chain acting on the post. Moreover, when using this procedure and
equipment, it was possible to pull a maximum of about sixty posts
in an eight hour day. In addition, this procedure and equipment
requires a substantial part of the post to extend above the ground,
and, while this is usually true in the case of fence posts such as
those used in connection with a snow fence, there are occasions
when only a very short length of the post is exposed above the
ground. This may, for example, be the case where the post is broken
off or where shorter posts are employed in anchoring guy wires or
the like. Heretofore, it has been very difficult to remove such a
post from the ground.
The present invention provides an inexpensive apparatus for
removing fence posts from the ground. The apparatus, quickly and
easily attaches to the fence post and provides a balanced pull on
the post when attached to a hoist which is exerting a vertical pull
on the apparatus. With this apparatus the forces in other than the
vertical direction are substantially opposed and balanced. The
apparatus avoids damage to the fence posts and so facilitates the
removal of the fence posts, that nearly three times as many (i.e.,
about 170 fence posts) can be removed during an eight hour day. The
apparatus utilizes a minimum number of parts, is inexpensively
constructed and is adapted for use in connection with existing
hoisting equipment.
SUMMARY OF THE INVENTION
In accordance with one aspect of the invention, a post pulling
apparatus is provided which includes a pair of post gripping
members which are apertured adjacent their respective one ends with
the apertures being of a size and shape to receive the post, and
when they are placed on the post and positioned in superposed
overlying relationship with respect to each other, the other or
distal ends of the members will extend outwardly in opposite
directions from the longitudinal axis of the post. A flexible
member, such as the chain, interconnects the distal ends of the
members and provides a means for attachment of the power hoisting
device thereto. When the flexible member is pulled upwardly by the
hoist, the gripping members will be tilted angularly with respect
to the post and with respect to each other so that the post will be
gripped by the post gripping members and the pulling forces will be
balanced on the post. That is to say transverse bending or twisting
forces applied to the post will be substantially opposed and
balanced by the two oppositely positioned gripping members.
It is preferred that the apertures in the post gripping members be
of substantially the same shape as the cross sectional profile of
the fence post being pulled so that the members will not rotate
about the longitudinal axis of the post but will remain in their
proper position with their distal ends oppositely disposed with
respect to one another.
It is preferred that the gripping members be in the form of metal
plates having substantially planar faces and, in the preferred
embodiment, the flexible member interconnecting the distal ends of
the gripping members is a link chain. The edge of the plate member
adjacent the aperture is rectilinear and preferably is
perpendicular to the longitudinal axis of the plate and to the
plane of the member so that when the members are assembled on the
post in superposed relationship and an upward force is exerted
against the flexible member to tilt the members upwardly at
approximately right angles with respect to each other, the edge
portion of the upper plate member will flatly engage the top
surface of the lower plate member and the two plate members will
form a unitary assembly for lifting the fence post out of the
ground.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a fence post pulling apparatus
constructed in accordance with this invention;
FIG. 2 is a perspective view of the apparatus after it has been
positioned on a fence post and attached to a hoist for pulling the
fence post out of the ground;
FIG. 3 is a side elevational view of a portion of the fence post
and the gripping members of the apparatus showing the relationship
of these members to one another and to the fence post as the fence
post is being pulled out of the ground by the apparatus;
FIG. 4 is a top plan view of a fence post showing one of the
plate-like post gripping members being positioned thereon; and
FIG. 5 is a side elevational view of the plate-like post gripping
member illustrated in FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With further reference to the drawing in FIG. 1, there is shown an
apparatus 10 for pulling fence posts 12 (see FIGS. 2-5). The
particular apparatus shown in the drawing is one for pulling fence
posts of standard construction; such fence posts are substantially
T-shaped, each having a leg portion forming a first flange 12a, and
a transverse portion forming a pair of opposited disposed flanges
12b and 12c. Extending in the opposite direction from the flange
12a are a plurality of hooks 14 which extend outwardly and
upwardly, as best illustrated in FIGS. 3 and 4. The flanges 12a,
12b and 12c, and the hooks 14, extend radially outwardly from the
longitudinal axis of the fence post.
The apparatus 10 includes a pair of fence post gripping members, 16
and 18. In the illustrated embodiment these gripping members are
elongated, and preferably rectangular steel plates, each having
planar top and bottom surface portions and a proximate edge portion
which is rectilinear and preferably perpendicular to the
longitudinal sides or axis of the member. Thus, the rectilinear
edge 18a is provided for the member 18, and the rectilinear edge
16a is provided for the member 16.
Each of the gripping members 16 and 18 is provided with an aperture
for receiving the fence post. Thus, gripping member 16 has an
aperture 20 and gripping member 18 has an aperture 22. The
apertures are located adjacent the proximate edge portions of their
respective gripping members, and these apertures are substantially
the same shape as the cross sectional profile of the fence post
being pulled. These apertures, however, are slightly larger than
the fence post cross section so that the gripping members may be
readily slid over the post in the direction of the longitudinal
axis of the post. The apertures 20 and 22 are mirror images of one
another, so that when positioned on the fence post 12 the distal
ends 16b and 18b of the gripping members 16 and 18, respectively,
will extend radially outwardly from the axis of the fence post in
opposite directions.
Since in the illustrated embodiment the fence post 12 are standard
and have T-shaped cross sectional profiles, the apertures 20 and 22
in the gripping members 16 and 18, respectively, are also
substantially T-shaped with an extension above the transverse
portion of the T to accomodate the hooks 14 of the fence post. The
size and shape relationship between the gripping member aperture
and the cross sectional profile of the fence post 12 is best
illustrated in FIG. 4.
The fact that the apertures 20 and 22 are substantially the same
shape as and just slightly larger than the cross sectional profile
of the fence post 12 serves to prevent any substantial rotation of
the gripping members 16 and 18 with respect to the fence post or
with respect to one another after they have been placed in position
on the fence post.
The transverse dimensions of the apertures 20 and 22 (i.e., the
vertical dimensions as viewed in FIG. 4) are governed solely by the
desideratum of sliding the gripping members easily onto the fence
post. However, the longitudinal dimensions of the apertures are
preferably governed not only by the desirability of easily sliding
the gripping members onto the fence post, but also by the
desirability of having the aperture defining portions engage and
grip the corresponding portions of the fence post when the gripping
members have been tilted to their predetermined gripping angles,
which are preferably approximately 45 degrees with respect to the
fence post, as illustrated in FIG. 3. Thus, the apertures 20 and 22
are preferably 45 degree projections of the cross sectional profile
of the fence post on the planar surfaces of the gripping members 16
and 18. This will affect the longitudinal dimensions of the
apertures 20 and 22, and as seen in FIG. 3, the thickness of the
members 16 and 18 will also be a factor in determining the
longitudinal dimensions of the apertures. The aperture-defining
portions at the top surface of each gripping member will engage one
side of the post, and the aperture-defining portions at the bottom
surface of each member will engage the opposite side of the post
when the members are tilted to their gripping angles. When the
gripping members 16 and 18 are moved to their angular gripping and
pulling positions, as illustrated in FIG. 3, it is preferable to
have as much of the aperture defining portions as possible in
gripping engagement with the fence post 12.
Since the apertures 20 and 22 are adapted to provide gripping for
the fence post when the gripping members are positioned at their
predetermined gripping angles, which in the illustrated embodiment
are angles of 45 degrees with respect to one another, it is
apparent that the gripping members themselves will, in this
position, be disposed at twice this angle or 90.degree. with
respect to one another. In this position the rectilinear proximate
edge portion 18a of the upper gripping member 18 will engage the
top planar surface of the lower gripping member 16, and the two
platelike gripping members will thus form a unitary assembly for
lifting the fence post out of the ground.
The distal ends 16b and 18b of the gripping members are
interconnected by means of a flexible member such as a link chain
24 which forms a loop between these opposed distal end portions 16b
and 18b, and provides a ready means for engagement by the hook 26
of the hoisting device 28. The hoisting device 28 may be any of the
standard and well known hoists that will apply sufficient lifting
force to the apparatus 10 to pull the post 12 from the ground. The
opposite ends of the chain 24 may be welded or otherwise fastened
to the distal ends 16b and 18b, respectively, of the gripping
members so that when the hoist 28 pulls the hook 26 upwardly with
the loop of the chain 24 engaged by the hook 26, the gripping
members 16 and 18 will be tilted first to the position illustrated
in FIG. 2 and then to their fully tilted angular gripping positions
illustrated in FIG. 3. In this latter position these gripping
members are at approximately 90.degree. with respect to one
another, and the aperture-defining portions of these gripping
members are in gripping engagement with the corresponding portions
of the fence post. A further lifting force applied to the chain 24
by the hoist will result in axially upward movement of the gripping
members 16 and 18, and the post will be pulled vertically upwardly
and out of the ground.
In this pulling operation, the upper gripping member or plate 18,
as viewed in FIG. 3 would normally tend to rotate the fence post in
a clockwise direction, whereas the lower gripping member 16 would
normally tend to rotate the post in a counter clockwise direction.
Since the forces applied to the fence post by each of these two
oppositely disposed gripping members is the same, the transverse or
turning forces will be substantially opposed and balanced. The
rectilinear proximate edge portion 18a flatly engages the top
surface of the lower gripping member 16, and there will, therefore,
be little tendency for any relative movement between the gripping
members 16 and 18, and these members will act as a unitary grip for
removing the post axially from the ground.
The apparatus 10 of this invention may be easily and inexpensively
constructed. The gripping members 16 and 18 may be constructed of
inexpensive steel plate, and the apertures 20 and 22 may be
broached, drilled, sawed or burnt into these plates by standard
shop equipment. If desired, the entire apparatus may be constructed
on the work site where the fence posts are being pulled.
The apparatus is quickly and easily assembled on each fence post to
be pulled by simply sliding the two gripping members 16 and 18
sequentially onto the fence post and then hooking the gripping
member connecting chain 24 onto the hook 26 of the hoisting device.
An upward pull on the chain will cause the two oppositely disposed
overlying gripping members to assume a right angle position with
respect to one another and their 45.degree. gripping position with
respect to the fence post, thus, balancing the forces for pulling
the fence post vertically out of the ground.
The apparatus 10 has been described in connection with the pulling
of standard T-shaped fence posts with mirror image T-shaped
apertures in the gripping members 16 and 18. This apparatus may,
however, be employed very satisfactorily to pull posts of round
cross section such as standard chain link fence posts or any
special shapes of posts such as those employed for guard rails. The
apertures in the gripping members 16 and 18 are formed to fit the
particular shape of the post being pulled. In the case of a post of
round cross section, the apertures 20 and 22 would be eliptical
(i.e., 45.degree. projections of the circular cross section). The
apparatus, moreover, may be used to pull posts of all types of
construction including those made of plastic, wood, metal or the
like, and these posts may be pulled even when imbedded in a base
such as concrete (in which case the base would be pulled with the
post).
It is to be understood that the present disclosure has been made
only by way of example and that many additional modifications and
changes in various details may be resorted to without departing
from the invention.
* * * * *