Abstract:
An apparatus for removing roof shingles includes an elongated body having a handle at its upper end and a lift plate pivotally connected to its lower end. The lift plate includes a removable blade at its leading edge and a roller that parallels the leading edge. The lift plate is linked to a pneumatically powered actuator that causes the lift plate to pivot about the roller upon the activation of a trigger mounted in the handle. The handle both rotates around the body and is movable linearly along the body against a biasing compression spring.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
   This application claims priority to Provisional Application No. 60/741,808, filed Dec. 5, 2005. 

   FIELD OF THE INVENTION 
   This invention is related to an apparatus for stripping roof shingles and nails. 
   BACKGROUND OF THE INVENTION 
   Roof shingles are difficult to remove from an existing roof. The shingle nails are also very difficult to remove. 
   Conventionally, roofers employ a shovel-like prying hand tool which is inserted beneath a shingle or nail. The tool is pivoted to raise the shingle and the nails. This is a very difficult and time-consuming process. It is therefore desirable to provide a power operated roof stripping device that eases the labor-intensive task of stripping shingles from a roof. 
   Some power operated roof striping devices are known in the prior art. These include U.S. Pat. No. 5,001,946 which issued Mar. 26, 1991 to the present inventors; U.S. Pat. No. 4,663,995 which issued May 12, 1987 to Frank M. Amundson; Herbert C. Manners; and Paul M. Jeffries; and U.S. Pat. No. 4,763,547 which issued Aug. 16, 1988 to John H. Dike, Jr. 
   In our previous invention disclosed in U.S. Pat. No. 5,001,946 we described a pneumatic lifting/prying tool that, while fully capable of stripping shingles off of a roof, suffered from several drawbacks. One of these drawbacks is that when the device was used, the stripped shingles would continue past the lifting blade and fall back down onto the newly stripped roof section. This results in the user having to clear away these stripped shingles to reach the next section of shingles and may result in the user getting injured by either tripping over the stripped shingles or by stepping on a removed nail. Another drawback is that the device is relatively heavy and must be carried by a user around the rooftop. Further, the pivot point on the bottom the lifting plate wears down during repeated use. 
   Therefore, there is a need for an improved roof shingle stripping apparatus that overcomes these and other drawbacks. 
   SUMMARY OF THE INVENTION 
   The broad purpose of the present invention is to provide an improved power-operated, roof stripping apparatus. The preferred embodiment of the invention, which will be described in greater detail, comprises an elongated body having a handle at its upper end and a lift plate pivotally connected to its lower end. The lift plate has at least one roller mounted beneath the pivotal connection to the body, generally parallel to the leading edge of the lift plate. The leading or forward edge is coupled to a removable blade that is inserted beneath a shingle or a nail for raising it. A curved shield is mounted atop the lift plate and directs removed shingles away from the upper end of the body. 
   The arrangement is such that after inserting the lift plate and blade beneath a shingle, the user can manually raise the shingle either by swinging the handle about the roller, or triggering a piston and cylinder actuator to pivot the lift plate about the roller, or, a combination of both efforts. The piston and cylinder actuator is connected by a toggle linkage to the rear edge of the lift plate. 
   The roller, beyond operating as a fulcrum when the apparatus is used to strip shingles allows a user to roll the apparatus from location to location. Having a roller as the fulcrum also reduces wear on the underside of the apparatus. 
   The handle improves user comfort by rotating about the end of the elongated body to reduce torque forces from being transmitted to the user as well as allowing a user to hold the handle in a position that is comfortable. A cushioning spring allows the handle to translate along the body and reduces impact forces transmitted through the lifting head to the user. 
   Still further objects and advantages of the invention will become readily apparent to those skilled in the art to which the invention pertains upon reference to the following detailed description. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The description refers to the accompanying drawings in which like reference characters refer to like parts throughout the several views, and in which: 
       FIG. 1  is a perspective view of a shingle stripping apparatus illustrating the preferred embodiment of the invention; 
       FIG. 2  is a side view of the lower end of the preferred apparatus; 
       FIG. 3  is a bottom view of the lower end of the preferred apparatus; 
       FIG. 4  is a partial perspective view of the shingle-engaging portions of the lift head; 
       FIGS. 5-6  illustrate the power-operated apparatus and toggle-linkage employed for pivoting the lift plate with respect to the lower end of the body; 
       FIG. 7  is a view similar to  FIG. 2  but in which the nail has been raised; 
       FIG. 8  is a side view of the upper end of the preferred apparatus; 
       FIG. 9  is a partial exploded view of the upper end of the preferred apparatus; 
       FIG. 10  is a perspective view of the shingle stripping apparatus having a pivoting elongated body; and 
       FIG. 11  is a exploded partial view of the pivoting portion of the shingle stripping apparatus illustrated in  FIG. 10 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to the drawings,  FIG. 1  illustrates a roof shingle stripping apparatus  10 . Apparatus  10  includes an elongated tubular body  12  having its upper end  14  terminating at a handle  16 . Its lower end  18  is pivotally coupled to a shingle lifting head  20 . 
   Handle  16  includes a trigger assembly  22  that is connected by a conduit  24  and fitting  26  to a source of pressurized air  28 . Conduit  24  is connected a conventional trigger assembly  22  having a pneumatic valve  30  and a trigger  32  for opening and closing communication with source  28 . A conduit  34  is connected to the outlet of valve  30  and is disposed inside handle  16  and tubular body  12  as is illustrated in phantom. 
   A piston and cylinder actuator  36  is mounted by a pair of brackets  38  (one bracket not shown) to the underside of body  12 . The cylinder  40  of the actuator is parallel to the length of the body. The lower end of conduit  34  is connected by a fitting  41  to the upper end of the actuator. The actuator has an internal piston (not shown) connected to a piston rod  42  in such a manner that when trigger  32  is squeezed by the user, the piston rod is extended from the cylinder. When the trigger is released, the piston rod is retracted as the pressurized air is exhausted from the cylinder, preferably through fitting  41  to the ambient. 
   Referring now to  FIGS. 2-4  and  7 , lift head  20  includes a generally flat lift plate  44 . Lift plate  44  has a pair of spaced lugs  46 . A pivot pin  48  pivotally connects the lower end of body  12  to lugs  46 . The lift plate is formed from heavy-gauge plate-like steel. 
   A roller housing  50  is coupled to the bottom surface  52  of the forward portion of lift plate  44 . Housing  50  is generally triangular in shape and rotatably retains a cylindrical roller  54  within the apex of the triangle (i.e., at its furthest point from surface  52 ). Roller  54  is preferably centered relative to cylinder  20  and body  12  and has a rotational axis that is generally parallel to lift plate pivot pin  48 . Roller housing  50  is located upon surface  52  such that roller  54  is in a location between pivot pin  48  and the leading edge. As will be described in greater detail below, roller  54  operates as a fulcrum to strip shingles and roofing nails from a roof. 
   Support ribs  56  provide additional rearward support to the triangular housing  50 . 
   Lift plate  44  preferably has a front edge  58  about 8-10 inches wide forming an edge that is generally parallel to the axis of rotation of body  12  with respect to the lift plate. Pivot pin  48  is mounted about 5 inches behind the lift plate&#39;s front edge. 
   Mounted to lift plate  44  across front edge  58  is a shingle-engaging blade  60 . Blade  60  is a generally rectangular plate that is removably coupled to lift plate  44  by conventional fasteners  61 . Blade  60  extends from front edge  58  generally parallel to the frontward portion of lift plate  44 . The forward or leading edge  62  of blade  60  has a plurality of open-ended slots  63 , each adapted to receive a nail when the lift plate is inserted beneath the nail head. Leading edge  62  and each slot  63  are beveled to assist insertion beneath a shingle. 
   It should be appreciated, and as best shown in  FIG. 2 , the roller housing  50  and leading edge  62  of the blade are normally the only surfaces that engage the roof. 
   A side skirt  64  extends downward from the side ends of blade  60 . Side skirt  64  has a lower edge  65  that abuts the roof  66  to prevent the apparatus  10  from tipping over the centrally located roller  54 . For example, if a nail is lifted with one of the outer slots  63 , the apparatus  10  may attempt to roll, generally about the axis of body  12 , toward the opposite side of the blade. The side skirt on this opposite side of the blade engages the roof to support the apparatus and prevent this roll-over. 
   The lift plate is bent at  67  to form a rear edge  68 . An upwardly facing flange or boss  69  having a pivot pin  70  is mounted on rear edge  68 . A pair of side flanges  71  extend from the opposite sides of rear edge  68 . 
   As best illustrated in  FIGS. 5 and 6 , a toggle linkage  72  is mounted between pivot pin  70  and piston rod  42 . Toggle linkage  72  includes a clevis  74  mounted on the end of the piston rod. A pin  75  pivotally connects the clevis to a link  76 . A pair of link means  78  are connected by pin means  80  to body  12 . A pair of link means  82  are mounted on pivot pin  70 . Pivot means  84  connect the ends of link  76 , link means  78  and link means  82  together in such a manner that as the piston rod is extended, link  76  pushes link means  78  with respect to link means  82  so that they unfold to pivot the rear edge of the lift plate away from body  12 . When the piston rod is retracted, link  76  pulls link means  78  and  82  so as to slightly fold link means  78  with respect to link means  82  together to move the rear edge of the lift plate toward the body. 
   A shingle or a nail may be lifted by inserting the leading edge of the blade beneath the shingle or other roofing structure, squeezing the trigger to actuate the cylinder and thereby cause the toggle linkage to unfold and apply a substantial lifting force about the roller on the leading edge of the blade. 
   Lift head  20  also includes a curved shingle guide scoop  86 . Scoop  86  is a curved plate that is mounted at its front edge  87  between the upper surface of lift plate  44  and blade  60 . Scoop  86  has the same approximate width as blade  60  and presents a concave shovel-like surface  88  facing the leading edge the blade. The rear edge  90  of the scoop flattens out and is coupled to a U-shaped brace  92  that is mounted to flanges  71  of the lift plate. As illustrated in  FIG. 7 , scoop  86  operates to deflect any lifted shingles and roofing nails back in the direction of the leading edge and away from body  12  and the user. It should be appreciated that if the apparatus is used on an angled rooftop, the scoop would direct the lifted roofing materials down the slope of the roof when a user starts stripping the roof down from its peak. 
   A sheet metal linkage cover or shield  94  having a generally U-shaped cross-section is removably coupled to body  12 . Shield  94  is wrapped around body  12  and overhangs on its two sides  93  to provide additional protection to the pivot means and links found in linkage  72  from any debris or other material that may pass beyond shingle guide scoop  86 . The forward end of shield  94  is preferably angled to accommodate the curved scoop and the angled relationship between lift plate  44  and body  12 . 
   Referring now to  FIGS. 1 ,  8 , and  9 , handle  16  is coupled to the upper end  14  of body  12 . Handle  16  includes a user hand-engaging portion  95  that is rotatably coupled to upper end  14  of body  12 . Portion  95  preferably includes a hand grip  96  that cooperates with two hand guards  97 ,  98  to define an enclosed, generally D-shaped, handle. Trigger  32  passes through the inner wall of grip  96  to allow a user to activate actuator  36 . The upper hand guard  97  includes an internal chase (not shown) that allows conduit  34  to pass therethrough. 
   The two hand guards or straps  97 ,  98  come together at a front face  100  of portion  95 . A tubular shaft  102  projects from front face  100 . A bushing  104  is slidably fit over shaft  102  adjacent to face  100 . The outer surface of bushing  104  is sized complementary to the inner diameter of body  12 . A second bushing  106  is located around body  12  and abuts bosses  107  that project radially from the outer surface of body  12 . Bosses  107  are preferably rivets punched into the tubular body a distance from the forward end that is slightly deeper along the body than the length of handle shaft  102 . Bosses  107  prevent bushing  106  from sliding down the body toward forward end  18 . In the preferred embodiment busing  106  is a washer formed from low-friction material, such as PTFE. 
   Bushings  104 ,  106  cooperate to allow the hand-engaging portion  95  to rotate out the longitudinal axis of body  12  in the directions shown by arrow  108 . 
   Handle  16  also includes a compression spring  109  that is disposed between bushings  104 ,  106  and is sized to fit around body  12 . When assembled, spring  109  biases portion  95  in the direction of arrow  110  while allowing portion  95  to deflect along the body in the direction of arrow  111  to cushion any forces transmitted from the operation of the apparatus to the user. 
   A tubular cover  112  is preferably fixed to the forward end of portion  95  by conventional fasteners, such as rivets  113 . Cover  112  includes a forward portion  114  that is sized to fit over spring  109  and the outer diameter of the body  12 . By fixedly coupling cover  112  to portion  95 , cover  112  rotates with portion  95  relative to body  12 . To prevent portion  95  from rotating to far and potentially damaging the internal conduit  34 , cover  112  includes a stop arm  116  that extends away from forward portion  114  parallel to body  12 . A pair of studs  118  that extend from body  12  cooperate with arm  116  to restrict movement in the directions of arrow  108 . 
   Referring back to  FIG. 1 , apparatus  10  further preferably includes a second handle  119 . Handle  119  includes a cylindrical shaft  120  that terminates in a concentrically disposed cushioned grip  122 . An annular ring  124  is removably and repositionably coupled along body  12  and includes a clevis  126 . Shaft  120  is pinned within clevis  126  such that shaft  120  and grip  122  extend perpendicularly from body  12 . In the preferred embodiment, the clevis mating end of shaft  120  is pinned to allow the shaft and grip to move slightly in the direction of the body. In another embodiment, grip  122  is mounted to shaft  120  in a manner that allows that grip to rotate about the shaft. In another embodiment studs  118  extend from annular ring  124 . 
   Apparatus  10  also includes a carrying handle  128  mounted to the body  12  above the shield  94 . Carrying handle  128  is preferably mounted proximate to the center-of-mass of the apparatus to facilitate carrying the shingle stripping apparatus. 
   In the preferred embodiment of the invention, a sliding brake or hook  130  extends from the underside of body  12  (i.e., on the same side as roller  54  and actuator  36 ). Brake  130  is an generally L-shaped bracket that extends perpendicularly from body  12  beyond actuator  36  and is operative to protect the actuator in the event the apparatus is dropped. Brake  130  includes a forward facing leg  132  that operates as a hook to resist sliding movement if the apparatus is left unattended on an a rooftop. To further reduce the chance of the apparatus rolling or sliding down a roof and to pad the apparatus if the handle is dropped, an elastomeric or rubber pad  134  is mounted to the bottom end of  132 . 
   Referring now to  FIGS. 10 and 11 , a shingle stripping apparatus  10  is shown including a pivoting or articulated section  136  along elongated body  12 . Pivoting section  136  is formed from elongated body  12  being severed in the approximate center along its length. The two severed ends  138 ,  140  are pivotally coupled together to allow the upper end  14  to be angled relative to lower end  18  and lift head  20 . 
   End  138  terminates in a clevis  142  formed from two parallel flanges that extend down and away from opposite sides of the end. Clevis  142  is spaced to receive end  140  and includes a pivot pin bore  144  and a lock pin bore  146  formed through the clevis. 
   End  140  includes a pivot pin bore  148  formed through the generally cylindrical body and three lock pin bores  150  that are radially spaced about bore  148 . 
   When pivot portion  136  is assembled body pivot pin  152  is inserted through one of the clevis&#39; pivot bores  144  and into pivot bore  148  formed in end  140  and then through the other clevis pivot bore. A mechanical fastener, such as nut  154  is threaded onto the end of pin  152  to hold pivot portion  136  together. 
   A lock pin  156  is selectively disposed through clevis bores  146  and one of the three angle adjustment bores  150  to position and hold the upper end  14  at an angle relative to lower end  18 . A temporary retainer, such as cotter pin  158 , holds lock pin  156  in position. 
   Clevis  142  and its bores  144 ,  146  are positioned on end  138  such that body pivot pin  152  and lock pin  156  are both parallel to roller  54  and leading edge  62  when passed through complementary bores  144 ,  148  and  146 ,  150 . 
   In the preferred embodiment, one of the lock pin bores  150  is aligned with pivot bore  148  to cause the pivot portion  136  to take no angle thereby resulting in the entire body  12  to be substantially straight. It should be appreciated that any number of lock pin bores  150  may be used to allow various angles to be selected and that other pivoting assemblies may be used to allow upper end  14  to angle away from lower end  18 . 
   The invention has been described in an illustrative manner, and it is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. Further, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced other than as specifically described.