Post puller

Information

  • Patent Grant
  • 6382594
  • Patent Number
    6,382,594
  • Date Filed
    Friday, July 28, 2000
    24 years ago
  • Date Issued
    Tuesday, May 7, 2002
    22 years ago
Abstract
The improved hydraulically operated post pulling apparatus is adapted to be mounted on a vehicle such as a skid steer mover. The post puller apparatus includes a support frame adapted to be mounted on the vehicle. The support frame includes a number of base member brackets that attach a base member or base plate to the support frame. The base member includes a post receiving recess that is adapted to receive a post from the side rather than the top. The post pulling apparatus also includes a top support plate that includes a post receiving indent, which also is adapted to receive a post from the side rather than the top. A rotating jaw member having a member of post-engaging teeth is pivotally mounted next to the post receiving indent on the top support plate. Opposite the rotating jaw member, a fixed jaw member is attached to the top support plate that includes a number of post-engaging faces. A clamping cylinder is mounted to the top support plate and includes a piston that is pivotally attached to the rotating jaw member. The piston, when extended, operates to pivot the rotating jaw member downwardly into engagement with the post to be engaged and removed from the ground. First and second pairs of bar links are each pivotally mounted at one end to the support frame and pivotally mounted at an opposite end to a forward panel that is preferably attached to the rear of the support plate. A pair of pulling hydraulic cylinders are mounted on the base member, each having a piston attached to the top support plate. When the pistons of the pulling hydraulic cylinders are extended, the bar link pivot allowing the top support plate to lift and raise the pole from the ground.
Description




TECHNICAL FIELD




The present invention relates generally to post pullers and, more particularly, to an improved attachment for use with hydraulic power sources for pulling posts from the ground.




BACKGROUND OF THE INVENTION




The removal of highway guardrails and fence posts, especially those mounted in concrete, is a very difficult task. This task is frequently accomplished in a rather haphazard and unsafe manner. Generally, extracting a post may be accomplished by wrapping a chain around the post, then pulling up on the chain until it is tight and will “bind” on the post. This requires a minimum of two persons—one to wrap the chain and keep a “binding” force tension on the chain, and one to operate the machine to lift or pull the post from the ground. This is a dangerous operation because the person wrapping the chain onto the post must manually keep tension of the chain while the equipment operator pulls the chain tight, and often the operator cannot fully see the other person while operating the machine. Highway guardrails are pulled in a similar manner—either by wrapping the guardrail with a chain or attaching a cable to the guardrail with a plate clamp or similar device. Additionally, the second person or helper must also unchain or unclamp the post or guardrail in order to move on the next one.




In addition, apparatus for pulling posts out of the ground are known in the art. Some such apparatus are so designed that they must be transported by hand to the site where they are to be used. Other apparatus, although designed to be vehicle mounted, are not provided with sufficient positive extracting force to be used for posts of larger sizes or that are set relatively deeply in the ground. Still others which are designed to be motor vehicle mounted have a minimal radius of operation or, at best, are confined to operation within an extremely limited radius from the vehicle. Still other post puller designs are incapable of effective use for removing posts of various diameters or cross-sectional shapes.




The forces required to pull a post from the ground are often very large and indeterminate, due to unknowns such as soil compaction, soil type, suction, and other unknown variables. Therefore, many prior art post pulling machines are incapable of pulling a post from the ground, even if there were a method of clamping or gripping the post. The actual pulling or lifting function often requires the use of a large machine, due to the high breakout lifting forces required. These larger machines are required because they must supply all of the lifting or pulling force. These larger machines can also be a hazard when operating in the confined spaces of a heavily traveled highway.




OBJECTS OF THE INVENTION




Accordingly, it is an object of the present invention to provide post puller adapted to be mounted on a prime mover or vehicle with a hydraulic power source that addresses the disadvantages of the above-described prior art.




It is a further object of the present invention to provide a post puller attachment that grips the post from the side or front and that is adapted to clamp the object to be removed from the ground relatively low to the ground.




It is still a further object of the present invention to provide a post puller attachment wherein the initial lifting or breakout force is supplied by the attachment which reacts against the ground and, as a result, is adaptable for use with relatively smaller and more maneuverable handling machinery such as skid steer loaders or small tractors.




It is yet a further object of the present invention to provide a post puller attachment which is characterized by rugged construction and ease of use.




Still other objects of the present invention will become apparent to those skilled in this art from the following description and drawing wherein there is described and shown a preferred embodiment of the invention. As will be realized, the invention is capable of other different embodiments, and its several details are capable of modification in various, obvious aspects all without departing from the invention. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.




SUMMARY OF THE INVENTION




To achieve the foregoing and other objects, and in accordance with one aspect of the present invention, an improved post puller is provided. The improved hydraulically operated post pulling apparatus is adapted to be mounted on a vehicle such as a skid steer mover. The post puller apparatus includes a support frame adapted to be mounted on the vehicle. The support frame includes a number of base member brackets that attach a base member or base plate to the support frame. The base member includes a post receiving recess that is adapted to receive a post from the side rather than the top.




The post pulling apparatus also includes a top support plate that also includes a post receiving indent, which is also adapted to receive a post from the side rather than the top. A rotating jaw member that includes a plurality of post-engaging teeth is pivotally mounted next to the post receiving indent on the top support plate. Opposite the rotating jaw member and also next to the post receiving indent, a fixed jaw member is attached to the top support plate that includes a number of post-engaging faces. A clamping cylinder is mounted to the top support plate and includes a piston that is pivotally attached to the rotating jaw member. The piston, when extended, operates to pivot the rotating jaw member downwardly into engagement with the post to be engaged and removed from the ground. First and second pairs of bar links are each pivotally mounted at one end to the support frame and pivotally mounted at an opposite end to a forward panel that is preferably attached to the rear of the support plate. A pair of pulling hydraulic cylinders are mounted on the base member, each having a piston attached to the top support plate. When the pistons of the pulling hydraulic cylinders are extended, the bar links pivot allowing the top support plate to lift and raise the pole from the ground.











DESCRIPTION OF THE DRAWINGS




The accompanying drawings incorporated in and forming a part of the specification illustrates several aspects of the present invention, and together with the description and claims serves to explain the principles of the invention. In the accompanying drawings:





FIG. 1

is a top plan view of the post puller of the present invention;





FIG. 2

is a front plan view of the post puller of the present invention;





FIG. 3

is a side plan view of the post puller of the present invention;





FIG. 4

is a side plan view of the rotating jaw component of the present invention;





FIG. 5

is a top plan sectional view showing the fixed jaw and rotating jaw of the present invention engaging a round post; and





FIG. 6

is a top plan sectional view showing an alternate embodiment of the present invention including a pair of rotating jaws engaging a post having an I-shaped cross section.











DETAILED DESCRIPTION OF THE INVENTION




Reference will now be made in detail to the present preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings, wherein like numerals indicate corresponding elements throughout the figures.




With reference to

FIGS. 1-3

, the improved hydraulically operated post pulling apparatus of the present invention is indicated generally by reference numeral


10


. It should be appreciated that the post pulling apparatus of the present invention is adapted to be mounted on a vehicle, such as a small tractor, skid steer mover, bulldozer, or other similar equipment. As best shown in

FIGS. 2 and 3

, the post pulling apparatus


10


of the present invention includes a support frame


34


that is adapted to be mounted on the skid steer mover or other vehicle. The support frame may be constructed of any suitable material and may consist of square or box tubing or of any other suitable structural elements. The support frame


34


also includes at least one, and preferably two, support brackets


42


that are disposed diagonally and that connect a base member portion


38


to the support frame


34


. The base member


38


further includes a post receiving recess


40


that is adapted to essentially receive and straddle a post


44


to be engaged, secured, and removed from the ground by the post pulling apparatus


10


.




According to an important aspect of the present invention, the post pulling apparatus


10


further includes a top support plate


20


. As best shown in

FIG. 1

, top support plate


20


includes a post receiving indent


22


that is adapted to receive and straddle the post to be removed from the ground from one or more sides of the post. This arrangement differs from that of many prior art devices in that posts are typically engaged from the top requiring additional space for equipment operation and leverage to extract the post. As seen in

FIG. 1

, the post receiving recess


40


of the base member


38


is preferably disposed substantially underneath and is aligned with the post receiving indent


22


of the top plate


20


so as to facilitate engagement of post


44


.




As best shown in

FIGS. 1

,


2


, and


4


, the post pulling apparatus


10


of the present invention includes a rotating jaw member


12


that is pivotally mounted in close proximity with the post receiving indent


22


of the top support plate


20


. The rotating jaw member


12


may be mounted directly on the top support plate


20


or may be mounted on a separate rotating jaw member mounting plate


24


, which is, in turn, mounted on top support plate


20


. The rotating jaw member


12


includes a post engaging surface


46


. Post engaging surface


46


of the rotating jaw member


12


preferably is comprised of a plurality of post engaging teeth as shown in FIG.


4


.




Clamping hydraulic cylinder means


16


are mounted in alignment with the rotating jaw member


12


and on top support plate


20


or the rotating jaw member mounting plate


24


. The clamping hydraulic cylinder means


16


includes a piston


18


that is displaceable along a longitudinal axis. This piston


18


is pivotally attached to and partially straddles the rotating jaw member


12


. When extended, the piston is advantageously adapted to rotate the rotating jaw member


12


downwardly by and into engagement with a post


44


to be removed from the ground.




A fixed jaw member


14


is provided and is mounted either directly on top support plate


20


or on fixed jaw mounting plate


26


, which is, in turn, mounted directly on top support plate


20


. Preferably, the fixed jaw member is substantially V-shaped and includes one or more preferably replaceable post engaging faces


28


. Post engaging faces


28


are adapted to engage and receive the post


44


in conjunction with the rotating jaw member


12


. Preferably, the fixed jaw component


14


is disposed and attached substantially adjacent with the post receiving indent


22


of the top support plate


20


. More preferably, the fixed jaw


14


is disposed opposite the rotating jaw member


12


.




In order to facilitate vertical lift of the top support plate


20


, the post puller apparatus


10


of the present invention includes one or more bar links


30


. Preferably, the post pulling apparatus


10


includes first and second pairs of bar links


30


. As best shown in

FIGS. 1 and 3

, each of the bar links


30


is pivotally mounted at a first end to the support frame


34


and are further pivotally mounted at second end to a forward panel component


48


. Preferably, forward panel


48


is attached to top support plate


20


substantially at an angle of 90°.




The post puller apparatus


10


of the present invention, as best shown in

FIGS. 2 and 3

, further comprises one or more pulling hydraulic cylinder means. Preferably, the post pulling apparatus


10


includes first and second pulling hydraulic cylinder means


50


. The first and second pulling hydraulic cylinder means are each preferably mounted on a mounting brace


54


at an angle to base member


38


. Each of the pulling hydraulic cylinder means


50


include a piston


52


displaceable along a longitudinal axis. Each of these pistons


52


is attached to the top support plate


20


. Preferably, each of these pistons


52


is attached to the underside of the top support plate


20


. When extended, the piston


52


of the first and second pulling hydraulic cylinder means


50


are adapted to raise the top support plate


20


.




In general, to operate the improved post pulling apparatus


10


of the present invention, the vehicle on which the post pulling apparatus


10


is mounted is driven up to the post


44


to be removed from the ground. The driver of the vehicle aligns the post


44


in the post receiving indent of the top support plate


22


and the post receiving recess


40


of the base member


38


. Preferably, the post


44


is either placed in contact with the fixed jaw post engaging faces


28


or is aligned substantially therewith. After the post


44


is in alignment, hydraulic power is activated that powers clamping hydraulic cylinder


16


, which, in turn, causes clamping hydraulic cylinder piston


18


to extend. Accordingly, the extension of this piston


18


causes the rotating jaw member


12


to rotate forwardly and downwardly such that the post engaging surface


46


of the rotating jaw member


12


engages the post


44


and drives into the fixed jaw engaging face


28


of the fixed jaw unit


14


. Accordingly, the post


44


to be removed is now securely clamped between the rotating jaw member


12


and fixed jaw


14


.




In order to remove the post from the ground, hydraulic power is directed to pulling hydraulic cylinders


50


. Preferably, a flow divider valve (not shown) is used to split the flow of oil substantially equally between the two pulling hydraulic cylinders


50


. When the pulling hydraulic cylinder pistons


52


are extended, the base member


38


is caused to exert force upon the ground, since the post


44


is engaged between the rotating jaw member and the fixed jaw member


14


. With continued pressure, the top support plate


20


and all of the components mounted thereon are caused to upwardly raise and are pivoted upwardly by the four bar links


30


. As a result, the post or other device to be removed from the ground is broken free and lifted from the ground and may be moved and carried to a desired location. Once loose from the ground, the post secured on the post puller can be raised out of the post hole by lifting the rotor arms of the steer skid loader or other vehicle and carried to a desired location. (See FIG.


5


).




It should be appreciated the configuration of the post pulling assembly


10


of the present invention is adapted to receive and extract post sizes that are essentially of any commonly used configuration. Preferably, the rotating jaw member and fixed jaw members are adjustable to secure and grip posts from one inch to eight inches in diameter. The rotating jaw member


12


and fixed jaw member


14


are configured to accommodate posts of essentially any shape or cross section, such as round posts (See

FIG. 5

) or posts having a square cross section. Posts of any construction, such as wood or steel posts, are able to be gripped and extricated by the post pulling apparatus of the present invention.




Although the components of the post pulling apparatus of the present invention may be comprised of essentially any suitable durable material, preferably the various components are made of hardened tool steel. Preferably, the rotating jaw member and fixed jaw members are pinned for easy adjustment and replacement when necessary.




Because the post is accepted into the post puller from the front, as opposed to loading the entire unit over the top of the post, posts may even be removed and replaced while leaving an existing fence intact. In addition, the configuration of the post receiving recess


40


of the base member


38


allows the post puller device


10


of the present invention to straddle not only the post


44


but any concrete or other setting means that supports the post. Accordingly, post support material is easily removed without interference from the base member


38


during extraction of the post.




As shown in

FIG. 6

, in an alternate embodiment of the present invention, the fixed jaw


14


may be replaced with a second rotating jaw member


12


. This would readily facilitate pulling beams having an I-shaped or T-shaped cross section, such as those commonly used to support guard rails.




The foregoing description of a preferred embodiment of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiment was chosen and described in order to best illustrate the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto.



Claims
  • 1. A hydraulically operated post-pulling apparatus adapted to be mounted on a vehicle comprising:a) a support frame adapted to be mounted on said vehicle, said support frame comprising one or more base member brackets; b) a base member attached to said support frame, said base member comprising a post receiving recess, said post receiving recess of said base member adapted to receive a post from one or more sides of said post; c) a top support plate comprising a post receiving indent, said post receiving indent of said top support plate adapted to receive said post from one or more sides of said post; d) a rotating jaw member pivotally mounted on said top support plate, said rotating jaw member comprising a post engaging surface, said rotating jaw member being mounted proximate to said post receiving indent; e) at least one fixed jaw member mounted on said top support plate, said fixed jaw member comprising one or more post engaging faces; f) clamping hydraulic cylinder means mounted to said top support plate, said clamping hydraulic cylinder means comprising a piston displaceable along a longitudinal axis, said piston of said clamping hydraulic cylinder means adapted to be pivotally attached to said rotating jaw member, said piston of said clamping hydraulic cylinder means being further adapted to pivot said rotating jaw member into engagement with said post; g) one or more bar links, each of said bar links being pivotally mounted at a first end to said support frame, each of said bar links further being pivotally mounted at a second end to a forward panel, said forward panel being attached to said top support plate; and h) first and second pulling hydraulic cylinder means mounted on said base member, each of said first and second pulling hydraulic cylinder means comprising a piston displaceable along a longitudinal axis, each piston of said pulling hydraulic cylinder means being attached to said top support plate, said pistons of said first and second pulling hydraulic cylinder means being further adapted to raise said top support plate.
  • 2. The post-pulling apparatus of claim 1 wherein said support frame is comprised of box tubing.
  • 3. The post-pulling apparatus of claim 2 wherein said support frame further comprises first and second support brackets that connect said base member with said support frame.
  • 4. The post-pulling apparatus of claim 1 wherein said post receiving recess is disposed substantially underneath and aligned with said post receiving indent.
  • 5. The post-pulling apparatus of claim 1 wherein said rotating jaw member further comprises a plurality of post engaging teeth.
  • 6. The post-pulling apparatus of claim 5 wherein said fixed jaw member is substantially V-shaped.
  • 7. The post-pulling apparatus of claim 6 wherein said fixed jaw member is disposed opposite said rotating jaw member.
  • 8. The post-pulling apparatus of claim 7 wherein said one or more bar links comprises first and second pairs of bar links.
  • 9. The post-pulling apparatus of claim 8 wherein said forward panel is attached to said top support plate substantially at an angle of approximately 90°.
  • 10. The post-pulling apparatus of claim 9 wherein each of said first and second hydraulic cylinder means is mounted on an angled mounting brace, each of said angled mounting braces being mounted on said base member.
Parent Case Info

The present application is based on and claims priority benefit of U.S. Provisional Patent Application Ser. No. 60/146,529, filed Jul. 30, 1999, the entire specification of which is incorporated herein by reference.

US Referenced Citations (14)
Number Name Date Kind
1452205 Madsen Apr 1923 A
2124154 Sovincz Jul 1938 A
2482950 Toftey Sep 1949 A
3647185 Phibbs Mar 1972 A
3823916 Shaw Jul 1974 A
3848850 Bemis Nov 1974 A
3871618 Funk Mar 1975 A
4256286 Hudgins Mar 1981 A
4706935 Thompson Nov 1987 A
4822006 McIntire Apr 1989 A
4846445 Pfeffer Jul 1989 A
5211374 Head et al. May 1993 A
5242152 Schatz Sep 1993 A
6056271 Riojas May 2000 A
Provisional Applications (1)
Number Date Country
60/146529 Jul 1999 US