JP2003080469 | COMPRESSION TOOL |
GARGIULO EUGENE (US)
US1873294A | 1932-08-23 | |||
US4745671A | 1988-05-24 | |||
US6536088B1 | 2003-03-25 | |||
US3739452A | 1973-06-19 |
1. | A device for removing modular forms, comprising: an elongated shaft having a rearward end and a forward end; a pulling head fixedly coupled to a forward end of the shaft, the pulling head defining an openended slot for receiving a form lever stud of a form to be removed from a wall; and a slide hammer slidably coupled to the shaft for generating an impact force to the form via the pulling head to thereby break a bond between the form and the wall. |
2. | A device as defined in claim 1, wherein the slide hammer has a weight of about ten pounds. |
3. | A device as defined in claim 1, further including a stop member located adjacent to the forward end of the shaft and rearwardly of the pulling head to prevent the slide hammer from moving beyond the stop member toward the forward end. |
4. | A device as defined in claim 1, further including a stop member located adjacent to the rearward end of the shaft to prevent the slide hammer from moving beyond the stop member toward the rearward end. |
5. | A device as defined in claim 1, further including a handle coupled to the rearward end of the shaft. |
6. | A device as defined in claim 5, wherein the handle includes a pin extending through the shaft in a direction generally perpendicular to a length of the shaft. |
7. | A device as defined in claim 1, wherein the slide hammer includes a gripping portion and guard members extending outwardly at longitudinal ends thereof for protecting the hand of a user while grasping the gripping portion. |
8. | A device as defined in claim 1, wherein the shaft is generally cylindrical. |
9. | A device as defined in claim 1, wherein the pulling head defines an opening at a rear portion for being received over the forward end of the shaft. |
10. | A device as defined in claim 9, further including lock nuts threadably received on the shaft at each side of the opening defined by the pulling head for fixedly coupling the pulling head to the shaft. |
11. | A device as defined in claim 10, wherein one of the lock nuts located on the shaft rearwardly of the opening of the pulling head serves as a stop member to prevent the slide hammer from moving beyond the stop member toward the rearward end. |
BACKGROUND Stripping plywood style forms from freshly poured walls is problematic in the amount of time needed to break the form loose and remove it from the wall.
Using conventional means such as, for example, a carpenters hammer or crowbar, the removal operation takes approximately 20-25 seconds to chip away the concrete from around the form tie, snap off the end of the tie, gouge the claw end of the hammer into the side of the form, pry it up away from the wall slightly, slide the claw end of the hammer between the wall and form to pry against the face of the form to break it free, and then remove the form and place it on the ground.
Other drawbacks with the above-mentioned removal operation include excessive time needed to remove inside corner forms, damage to the steel corner forms from having to hammer them to break them free from the wall, damage to the edges of the plywood forms from gouging the claw end of the hammer into it- effectively making the form thicker at the edges so as to make obtaining a smooth transition from the face of one form to the adjacent form difficult. The end results are an uneven surface of the wall when the forms are removed, damage such as gouges and roughness to the face of the forms from prying against it to break it away from the wall (resulting in undesirable blemishes on the finished surface of the wall), and additional expense to the contractor for having to repair the surface of the wall, recondition the face of the forms, or replace the forms prematurely because of excessive wear and tear created by destructive stripping methods.
Accordingly, it is a general object of the present invention to overcome the drawbacks of prior tools for removing forms from walls.
SUMMARY OF THE INVENTION The present invention is directed to a device for removing modular forms.
The device comprises an elongated and preferably cylindrical shaft having a rearward end and a forward end. A pulling head is fixedly coupled to a forward end of the shaft. The pulling head defines an open-ended slot for receiving a form lever stud of a form to be removed from a wall. A slide hammer is slidably coupled to the shaft for generating an impact force to the form via the pulling head to thereby break a bond between the form and the wall. The slide hammer has a substantial weight of, for example, about ten pounds. The slide hammer has a gripping portion and preferably includes guard members extending outwardly at longitudinal ends thereof for protecting the hand of a user while grasping the gripping portion.
The device preferably includes a stop member located adjacent to the forward end of the shaft and rearwardly of the pulling head to prevent the slide hammer from moving beyond the stop member toward the forward end. The device also preferably includes a stop member located adjacent to the rearward end of the shaft to prevent the slide hammer from moving beyond the stop member toward the rearward end. Moreover, the device can include a handle coupled to the rearward end of the shaft. The handle, for example, includes a pin extending through the shaft in a direction generally perpendicular to a length of the shaft.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of a device for removing modular forms in accordance with the present invention.
FIG. 2 is a front perspective view of the pulling head of the device of FIG. 1.
FIG. 3 is a back perspective view of the pulling head of the device of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. 1, a device for removing modular forms in accordance with the present invention is indicated generally by the reference number 10. The device 10 includes an elongated shaft 12 having a forward end 14 and a rearward end 16. A slide hammer 18 is slidably coupled to the shaft 12 for movement back and forth therealong generally between the forward end 14 and the rearward end 16. The shaft 12 is preferably cylindrical in cross section, but may take other cross- sectional forms such as being square or rectangular without departing from the
scope of the present invention. A pulling head 20 is fixedly coupled to the shaft 12 at the forward end 14. The device 10 may include stop members located adjacent to the forward end 14 and the rearward end 16 of the shaft 12 for preventing the slide hammer 18 from moving along the shaft beyond the stop members as is explained more fully below. The device 10 may also include a handle 26 coupled to the rearward end 16 of the shaft 12 for gripping with one hand while moving the slide hammer 18 with the other hand. As shown in FIG. 1, the handle 26 may be in the form of a pin extending outwardly from the shaft 12, but may take other forms without departing from the scope of the present invention.
The slide hammer 18 defines a bore 28 extending therethrough from a first end 30 to a second end 32 for slidably receiving the shaft 12 within the bore. A cross-sectional area or diameter of the bore 28 is slightly larger than that of the shaft 12 for permitting the slide hammer 18 to easily move therealong while limiting lateral play of the slide hammer relative to the shaft. The slide hammer 18 has a substantial weight of, for example, about ten pounds, for generating a large impact force to a form to be removed from a wall. As shown in FIG. 1, the slide hammer 18 includes a gripping portion 34 and is preferably interposed between guard members 36,38 extending radially outwardly from the gripping portion for protecting the hand of a user.
The pulling head 20 includes a forward portion 40 defining an open-ended slot 42 for engaging a form lever stud. The pulling head 20 also defines an opening 44 at a rear portion 46 for being received over the forward end 14 of the shaft 12.
The pulling head 20 is fixedly coupled to the forward end 14 of the shaft 12 with, for example, retaining lock nuts 48,50 threadably received along the shaft adjacent to each side of the opening 44 of the pulling head. The retaining lock nut 48 located on the shaft 12 adjacent to the forward end 14 thereof and rearwardly of the opening 44 of the pulling head 20 serves as a first stop member to prevent the slide hammer 18 from moving beyond the first stop member toward the forward end 14 of the shaft.
A second stop member 52 may be fixedly disposed along the shaft 12 adjacent to the rearward end 16. The second stop member 52 includes a portion having a larger cross-sectional area or diameter relative to that of the bore 28 of the slide hammer 18 to prevent the slide hammer from moving beyond the second stop member toward the rearward end 16 of the shaft 12.
In operation, the open-ended slot 42 defined by the forward portion 40 of the pulling head 42 slides over and engages a form lever stud of a modular form to be removed from a wall. The pulling head 20 uses the stud as a pulling point to remove the form from the wall, thereby generally eliminating the damage otherwise caused by the gouging of the claw of a conventional hammer or crowbar.
A user of the device 10 grasps the gripping portion 34 of the slide hammer 18 with one hand and may grasp the handle 26 with the other hand. The user rapidly moves the slide hammer 18 back and forth along the shaft 12 one or more times as necessary to remove the form from the wall.
During each stroke of the slide hammer 18 toward the forward end 14 of the shaft 12, the impact of the slide hammer against the first stop member 48 suddenly stops the forward movement of the slide hammer. The substantial weight of the slide hammer 18 suddenly stopping against the first stop member 48 generates a large impact force which is propagated forwardly from the shaft 12 to the pulling head 20 to thereby deliver the impact force to the form to be removed. Several such impact forces causes the form to rapidly vibrate relative to the wall so as to weaken and break the bond between the form and the wall.
During each stroke of the slide hammer 18 toward the rearward end 16 of the shaft 12, the impact of the slide hammer against the second stop member 52 suddenly stops the rearward movement of the slide hammer. The substantial weight of the slide hammer 18 suddenly stopping against the second stop member 52 generates a large rearward force which is propagated to the pulling head 20 to thereby aid the user in pulling the form from the wall upon breaking the bond between the form and the wall.
Employing a device for removing modular forms in accordance with the present invention significantly reduces the time to remove a form from a wall relative to conventional devices from 20-25 seconds to 6-8 seconds. Eliminating the damage otherwise caused by the use of conventional removal techniques not only decreases the removal time by about 67% to about 75%, but also eliminates the other above-mentioned problems created by the use of conventional removal methods.
As will be recognized by those of ordinary skill in the pertinent art, numerous modifications and substitutions may be made to the above-described embodiment of the present invention without departing from the scope of the invention. Accordingly, the preceding portion of this specification is to be taken in an illustrative, as opposed to a limiting sense.
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