The present invention relates generally to a lifting device and more particularly to a pry bar with a fulcrum assembly which is slidably mounted on the pry bar.
Pry bars are commonly used for lifting furniture in the moving industry and in the carpet cleaning industry in order to place a slide under the furniture so that it may be easily moved.
The pry bar of the present invention pertains to pry bars with an adjustable fulcrum which allows a user to obtain the optimum leverage when engaging the object to be lifted with the pry bar lifting end.
Presently there are two such known pry bar assemblies with an adjustable fulcrum member. One is illustrated in U.S. Pat. No. 7,618,020, which discloses an adjustable fulcrum for use with a conventional pry bar. The fulcrum member consists of a tubular body with opposed slots in the sidewall thereof to receive the pry bar. The fulcrum body is generally made of a plastic, such as HDPE. An existing problem incurred with the adjustable fulcrum member of this invention is that the pry bar can slide relative to the fulcrum member after the load is engaged with the pry bar, and the fulcrum position therefore cannot be reliably retained and the fulcrum position must be changed by direct hand manipulation of the fulcrum body.
A pry bar with a sliding fulcrum assembly is also illustrated in U.S. Pat. No. 7,673,848. A problem incurred with the slidably mounted fulcrum assembly disclosed in this patent is that the fulcrum assembly must be hand manipulated and engaged and disengaged. It does not freely slide along the pry bar and therefore is not capable of self-adjustment.
It is an object of the present invention to provide a slidable fulcrum assembly which freely floats along the upper surface of the pry bar for self-adjustment to provide maximum lifting efficiency, yet when lifting pressure is applied to the fulcrum assembly by the pry bar, the pry bar engages the fulcrum assembly to automatically prevent any further relative movement between the pry bar and the fulcrum assembly.
The combination pry bar and sliding fulcrum assembly of the present invention includes an elongated pry bar having a generally horizontally extending lifting arm with a lifting lip at its distal end for engaging an object to be lifted, and an upright elongated handle coupled to the proximal end of the lifting arm through a curvature. The sliding fulcrum assembly consists of a body with a passage through the body which is configured and contoured for the body to normally freely slide along the bar, including the curvature thereof, when the fulcrum body is hanging on the bar. The fulcrum assembly body has a bottom curvature for engaging a floor surface as a fulcrum. The axis of this bottom curvature extends transversely to the central axis of extension of the elongated pry bar to provide a rocking fulcrum contact surface.
The bottom of the passage through the fulcrum assembly is provided with a bar friction engagement surface on a bottom portion of the passage whereby the sliding fulcrum assembly body is non-slidably engaged with the pry bar when the bottom curvature of the body is engaged with a floor surface under applied lifting force of the lifting lip of the pry bar against an object to be lifted.
This bar friction engagement surface consists of a material of high coefficient of friction, such as TPE.
This friction engagement surface may also include a wedged shaped configuration whereby the friction engagement surface frictionally engages the bar with a wedging action in order to further enhance the gripping action between the pry bar and the fulcrum assembly.
The pry bar and the passage through the fulcrum assembly may have a corresponding non-round cross sectional configuration whereby the fulcrum body is prevented from rotating on the bar.
An advantage of the combination of the present invention is that the pry bar is provided with a free floating fulcrum assembly which self-adjusts on the pry bar when initially engaging the pry bar with an object to be lifted. It also permits the operator to be positioned closer to the object to be lifted thereby providing effective leverage and maneuverability in tight spaces, and once the lifting force is applied to the bar, there is assurance that the pry bar will not slip relative to the fulcrum assembly.
The combination pry bar and sliding fulcrum assembly of the present invention provides a free floating fulcrum assembly which will readily self-adjust and positively engage with the pry bar when lifting force is applied. It permits the operator to work closer to the object being lifted, and it also provides a safer lifting mechanism than a pry bar which is provided with a wheeled fulcrum.
Other objects and advantages appear hereinafter in the following description and claims. The accompanying drawings show, for the purpose of exemplification, without limiting the scope of the invention or the appended claims, certain practical embodiments of the present invention wherein:
Referring to the drawings, the combination 10 of the present invention is comprised of pry bar 11 with a sliding fulcrum assembly 12. The pry bar 11 has a generally horizontally extending lifting arm 13 with a lifting lip 14 at its distal end 15 for engaging an object 16a (
Sliding fulcrum assembly 12 consists of body 20 having passage 21 therethrough which is configured and contoured for the body 20 to normally freely slide along bar 11, including curvature 19, when hanging on bar 11. Body 20 is provided with a bottom contact surface having a curvature 22 for engaging a floor surface 23 as a fulcrum for pry bar 11. The axis of this bottom curvature 22 extends transversely to the central axis of extension of elongated pry bar 11.
The bottom 24 of passage 21 is provided with a bar friction engagement surface 25 at the bottom portion thereof whereby the body 20 is non-slidably engaged with pry bar 11 when the bottom curvature 22 of the body is engaged with a floor surface 23 under applied lifting force of the lifting lip 14 against an object 16A or 16B to be lifted.
The body 22 may be molded of HPDE and the friction engagement surface 25 is an insert molded of a material with a high coefficient of friction, such as TPE.
In the variation shown in
The pry bar 11 and the corresponding passage 21 in body 22 have non-round cross sectional configurations, in this instance, a generally oval configuration. This prevents the body 22 from rotating on pry bar 11.
As shown in
To the contrary, when the base of an object which normally rests on the floor surface 23 as object 16b in
This application is a continuation-in-part of U.S. Design Patent Application No. 29/370,858, filed Sep. 14, 2010, and entitled FURNITURE LIFT.
Number | Date | Country | |
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Parent | 29370858 | Sep 2010 | US |
Child | 13135115 | US |