Roof membrane and insulation removing device

Abstract

A device for stripping a waterproof rubber membrane and foam insulation from a roof. The device includes a wheeled frame having a pair of handlebars at its rear for steering by a walking attendant. A first cutting blade is secured to the front of the wheeled frame and is rotatable about a substantially vertical axis. A pair of second cutting blades is secured to the front of the wheeled frame on opposite sides of the first cutting blade. Each one of the second cutting blades is rotatable about a substantially horizontal axis. A prime mover is secured to the frame for rotating the first cutting blade and the second cutting blades.

Description

FIELD OF THE INVENTION

The present invention relates generally to cutlery and, more particularly, to cutting tools mounted on vehicles moved during cutting.

BACKGROUND OF THE INVENTION

Impermeable rubber membranes positioned atop foam insulation are commonly used to make watertight roofs on commercial buildings. Over time, ultraviolet radiation, temperature changes and acid rain deteriorate these membranes, necessitating their replacement. The principal tool used to accomplish this task is a heavyweight, tipping the scales at about half a ton, which cuts membrane-anchoring screws and rips up membrane with a sawing blade. Unfortunately, this tool also vibrates metal roof decking, sometimes to the point of buckling, and shakes loose ceiling tiles on the interior of buildings. For this reason, roofers sometimes employ handheld, but powered, screwdrivers and shears to unfasten anchoring screws so that a roof membrane can be lifted and replaced. The process of removing a membrane, however, is slow with handheld tools.

SUMMARY OF THE INVENTION

In light of the problems associated with the known tools for detaching old membranes and foam insulation from building roofs, it is a principal object of the invention to provide a device that not only eliminates the handwork involved in detaching a membrane and insulation from a roof, but quickly accomplishes this task without damaging the steel decking that supports the membrane and insulation. The device cuts the membrane and insulation, measuring from one inch to eight inches thick, vertically and horizontally into elongated strips that are easy to handle. After cutting, the device gathers the strips for easy disposal. Any screws employed to secure the membrane and insulation are severed as the membrane and insulation are simultaneously cut and lifted from a roof.

It is a further object of the present invention to provide a device of the type described that, as a membrane and insulation are being cut, severs any screws employed to secure the membrane and insulation in place. The tasks of cutting membrane, insulation and fasteners are accomplished in a single pass with minimal vibration. At the present time, no product, other than the device described herein, exists that will simultaneously cut roof membrane, insulation and fasteners securing the membrane in place.

It is another object of the present invention to provide a roof membrane and insulation removing device of the type described that is compact in size. The device is easy to position on a roof and, once there, is far less likely to damage to roof decking than larger machines.

It is an additional object of the present invention to provide a device of the type described that has a self-contained power source so it does not need to be tethered by cables to a remote generator or electrical grid thus making the device very maneuverable.

It is a further object of the invention to provide a device of the type described that is self-leveling, retaining its cutting blades in position for optimum cutting regardless of the bumps, trash and other surface irregularities that the device may roll over. The result is strips of membrane and insulation of even width and thickness that are quickly cut from a roof.

It is an object of the invention to provide improved features and arrangements thereof in a roof membrane and insulation removing device for the purposes described that is inexpensive to manufacture and dependable in use.

Briefly, the device in accordance with this invention achieves the intended objects by featuring a wheeled frame having a pair of rearwardly extending handlebars for steering by a walking attendant. A first pair of cutting blades is secured to the front of the frame. Each of the first cutting blades is rotatable about a substantially vertical axis. A second pair of cutting blades is secured to the front of the frame on opposite sides of the first cutting blades. Each of the second cutting blades is rotatable about a substantially horizontal axis. A prime mover is secured to the frame for rotating the first and second cutting blades. Between the second cutting blades is secured a ramp assembly upon which stripped roofing materials are collected for disposal.

The foregoing and other objects, features and advantages of the present invention will become readily apparent upon further review of the following detailed description of the preferred embodiment as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be more readily described with reference to the accompanying drawings, in which:

FIG. 1 is a side view of a roof membrane and insulation removing device in accordance with the present invention having its hydraulic fluid conduits detached for the sake of drawing simplicity.

FIG. 2 is a top view of the roof membrane and insulation removing device of FIG. 1 having its hydraulic fluid conduits detached.

FIG. 3 is a rear view of the roof membrane and insulation removing device having its hydraulic fluid conduits detached.

FIG., 4 is a schematic diagram of the hydraulic system of the roof membrane and insulation removing device.

Similar reference characters denote corresponding features consistently throughout the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the FIGS., a roof membrane and insulation removing device in accordance with the present invention is shown at 10. Device 10 includes a wheeled frame 12 having a pair of handlebars 14 at its rear for steering by a walking attendant. At the front of frame 12 are supported a first pair of cutting blades 16 and 18 being rotatable about substantially vertical axes. On opposite sides of blades 16 and 18 is a second pair of cutting blades 20 and 22, these being rotatable about a substantially horizontal axis. A pair of hydraulic motors 24 and 26 and spin blades 16-22 so that such can slice into and through a roof membrane, foam insulation and penetrating fasteners. Another motor 28 rotates a pair of wheels 30 to mover device 10 over a roof. During use, debris severed from a roof by device 10 is collected for periodic disposal on a ramp assembly 32 positioned at the front of frame 12.

Frame 12 has a front portion 34 and a rear portion 36 joined together by a pivot pin 38 that permits portions 34 and 36 to twist relative to one another to accommodate uneven rolling surfaces. Front portion 34 is an openwork box having a pair of lower side rails 40 and a pair of upper side rails 42 extending forwardly from a back plate 44 penetrated by pivot pin 38. Similarly, rear portion 36 is an openwork box with a front plate 46 through which pin 38 pivotally extends. A pair of retaining pins 48, secured to plate 44 beneath pin 38, penetrate arcuate slots 50 in plate 46 and serve as a stop to prevent excessive, relative twisting of portions 34 and 36.

A cutting blade carrier 52 is pivotally fastened to front portion 34. As shown, carrier 52 has a pair of pivot arms 54 joined at their front ends by a carrier bar 56 and joined at their rear ends by a tie bar 58 and at their midpoints by a medial bar 59. Pivot pins 60 fasten arms 54 at their midpoints to the front ends of lower side rails 40. Threaded rods 62 extend outwardly from the rear ends of arms 54 and penetrate slotted brackets 64 provided on rails 40 rearwardly of pins 60. Nuts 66 on threaded rods 62 are clamped against brackets 64 to fix the inclination of carrier bar 56 and hence the height of blades 16-22 carried thereby.

A pair of rotatable wheels or casters 68 is secured to tie bar 58 and maintain front portion 34 and blade carrier 52 at a predetermined height above a supporting surface. Casters 68 each include a threaded shaft (not shown) that threadably engages a socket within tie bar 58. By manual rotation of the shaft in the socket, the distance from the bottom of casters 68 to tie bar 58 can be varied as desired by a user thus providing additional means for adjusting the cutting height of device 10.

Each of cutting blades 16 and 18 is circular in outline and includes a peripheral edge having small teeth or, in the alternative, being imbedded abrasives for cutting purposes. Cutting blades 16 and 18 are secured to the bottom ends of stub shafts 70 that rotate in journal bearings 72 affixed to carrier bar 56. Shafts 70 retain sprocket gears 74 between bearings 72 and blades 16 and 18. Each of the gears 74 is engaged with an endless chain 76 that, when moved as described below, causes blades 16 and 18 to be rotated at high speed.

Chain 76 extends rearwardly from sprocket gears 74 and is looped around a sprocket gear 78 affixed to the drive shaft 80 of hydraulic motor 24. Motor 24 is affixed to medial bar 59. Thus, when carrier 52 is pivoted up or down on pivot pins 60, motor 24 and gears 74 and 78 move together to prevent the binding of chain 76.

Cutting blades 20 and 22 are like blades 16 and 18 in that they possess either teeth or abrasives along their circular peripheries for cutting. Preferably, blades 20 and 22 are secured to stub shafts 82 that rotate in journal bearings 84 carried between paired support arms 86 whose rear ends are fastened to the sides of ramp assembly 32. On shafts 82, between paired arms 86, are secured sprocket gears 88. The gears 88 are engaged with endless chains 90 that are employed to rotate shafts 82 and blades 20 and 22.

Ramp assembly 32 is affixed to the front of portion 34 of frame 12 to collect strips of roofing membrane cut during use of device 10. Ramp assembly 32 has a ramp 33 from which a number of tines 35 project downwardly and forwardly. Ramp 33, as illustrated, has a downwardly sloping forward portion 33a that elevates cut membrane and insulation onto a horizontal rearward portion 33b as device 10 moves forward. Tines 35 extend downwardly and forwardly from forward portion 33a to lift just-cut membrane and insulation onto forward portion 33a.

Chains 90 extend rearwardly from sprocket gears 88 and are looped around sprocket gears 92 affixed to the opposite ends of a rotatable shaft 94. Shaft 94 is carried by journal bearings (not shown) mounted upon side rails 40. Adjacent one of these journal bearings, a sprocket gear 96 is affixed to shaft 94. Looped around gear 96 is an endless chain 98 that extends rearwardly to engage a sprocket gear 100 affixed to the horizontal drive shaft 102 of hydraulic motor 26. Motor 26 is mounted upon the bottom of front frame portion 34.

Drive wheels 30 are rotatably supported at the rear of rear portion 36 of frame 12 by a rotatable shaft 104. A drive wheel 30 is secured to each of the opposed ends of shaft 104 for retaining rear portion 36 above a supporting surface 106. A sprocket gear 108 is secured to shaft 104 adjacent one wheel 30. An endless chain 110 engages gear 108 and extends forwardly therefrom to engage a sprocket gear 112 affixed to the horizontal drive shaft 114 of hydraulic motor 28. Motor 28 is mounted upon the bottom of rear frame portion 36.

A prime mover being an internal combustion engine 114 is mounted atop front portion 34 of frame 12 so as to power a two-stage pump 116. As shown, pump 116 is fastened directly to engine 114 and has two, separate, pumping units 116a and 116b being capable of delivering separate streams of hydraulic fluid under pressure at predetermined flow rates. Pumping unit 116a has a fluid inlet and a fluid outlet that do not communicate directly with the fluid inlet and outlet of pumping unit 116b.

While engine 118 is running, hydraulic fluid is delivered from a reservoir 118 to pumping units 116a and 116b through a suction conduit 120. Hydraulic fluid is discharged from pumping unit 116a into a discharge conduit 122 for delivery to motors 24 and 26. Discharge conduit 122 is provided with a manually operated valve 124 that selectively permits the flow of hydraulic fluid to motors 24 and 26 connected in series with reservoir 118. (Note: bypass conduits permitting the continuous pumping of fluid by pump 116 are not shown in the FIGS. for the sake of simplicity.) With hydraulic fluid flowing through motors 24 and 26 such will operate to rotate drive shafts 80 and 102 and cutting blades 16-22 through the transmission system previously described. Hydraulic fluid exiting motors 24 and 26 is returned to reservoir 118 via return conduit 126.

Hydraulic fluid is delivered from a reservoir 118 to motor 28 through a suction conduit 128 while engine 118 is operating. Hydraulic fluid is discharged from high-pressure pumping unit 116b into a discharge conduit 128 for delivery to motor 28. Discharge conduit 128 is provided with a manually operated valve 130 that controls the flow of hydraulic fluid to motor 28. Valve 130 is shown in FIG. 4 to be situated so that its segment N is engaged with conduit 128 whereby hydraulic fluid flows to and from valve 130 into return conduit 132 without accomplishing useful work meaning that device 10 remains in neutral or at rest. Should valve 130 be shifted so that its F segment is engaged with conduit 128, hydraulic fluid is permitted to flow to motor 28 to rotate shaft 104 and wheels 30 to move device 10 forward. Finally, if valve 130 be shifted so that its R segment is engaged with conduit 128, hydraulic fluid is permitted to flow to motor 28 to rotate shaft 104 and wheels 30 to move device 10 backward or in reverse.

To avoid overheating the hydraulic fluid, a portion of its flow is diverted from return conduit 132 to a cooler 134 mounted on handlebars 14. After the hydraulic fluid passes through cooler 134, it is discharged into reservoir 118. Once in reservoir 118, the hydraulic fluid can be withdrawn to power any of motors 24, 26 and 28.

From the foregoing, it should be appreciated that use of device 10 is straightforward.

First, device 10 is placed on a supporting surface 106 that would normally comprise the steel decking of a roof atop which is secured a water-resistant membrane and insulation in need of replacement. Next, the membrane and insulation are manually lifted to expose its bottom surface to blades 16-22 at the start of a cut. Then, valve 128 is set to energize motor 28 to rotate wheels 30 and drive device 10 forwardly. The forward movement of device 10 presses blades 16-22 against the membrane and any metallic fasteners used to anchor such to surface 106. Now, valve 124 is opened to energize motors 24 and 26 thereby causing blades 16-22 to rotate and cut the membrane, insulation and any exposed fasteners.

Cutting of the membrane and insulation proceeds at a rapid pace with device 10 moving at a pace approaching that of a self-propelled lawnmower. The membrane and insulation are cut in long strips having a width substantially equal to the spacing between blades 20 and 22. The length of the cut strips will depend in large part on the type and condition of the membrane and insulation being worked upon but, may in many cases, would be measured in tens of feet.

If blades 16 and 18 appear to be scraping upon surface 106 as membrane and insulation removal progresses, they can be raised. To do this, nuts 66 merely need to be loosened so that the front of cutting blade carrier 52 can be elevated a suitable amount. Similarly, lowering the front end of carrier 52, while nuts 66 are loosened, lowers blades 16 and 18.

Because device 10 is highly maneuverable, the process of removing a roofing membrane and insulation can be accomplished in substantially less time than required when using conventional tools regardless of the skill of the user. A job that formerly would have required weeks to complete can now be completed in days.

While the invention has been described with a high degree of particularity, it will be appreciated by those skilled in the art that modifications can be made thereto. For example, the number and location of cutting blades 16-22 can be increased or decreased to suit the needs of a particular user with additional blades permitting the more rapid removal of roof membrane. Also, with the attachment of a hydraulic ram to front portion 34 of frame 12, casters 68 can be provided with a power steering mechanism operated by a user. Therefore, it is to be understood that the present invention is not limited to the sole embodiment described above, but encompasses any and all embodiments within the scope of the following claims.

Claims

1. A roof membrane and insulation removing device, comprising:

a wheeled frame having a pair of rearwardly extending handlebars;

a first cutting blade being secured to the front of said wheeled frame and being rotatable about a substantially vertical axis;

a pair of second cutting blades being secured to the front of said wheeled frame on opposite sides of said first cutting blade, each one of said second cutting blades being rotatable about a substantially horizontal axis; and,

a prime mover being secured to said frame for rotating said first cutting blade and said second cutting blades.

2. The roof membrane and insulation removing device according to claim 1 further comprising a ramp assembly secured to the front of said wheeled frame, said ramp assembly including a plurality of lifting tines extending forwardly of said first cutting blade.

3. A roof membrane and insulation removing device, comprising:

a wheeled frame having a pair of rearwardly extending handlebars;

a first pair of cutting blades being secured to the front of said wheeled frame, each one of said first pair of cutting blades being rotatable about a substantially vertical axis;

a second pair of cutting blades being secured to the front of said wheeled frame adjacent said first pair of cutting blades, each one of said second pair of cutting blades being rotatable about a substantially horizontal axis; and,

a prime mover being secured to said frame for simultaneously rotating said first pair of cutting blades and said second pair of cutting blades.

4. The device according to claim 3 wherein said wheeled frame includes a front portion and a rear portion capable of relative pivoting about a substantially horizontal axis, said front portion supporting said first pair of cutting blades, said second pair of cutting blades and said prime mover, said front portion having casters retaining such above the ground and said rear porting having wheels retaining such above the ground.

5. The device according to claim 3 further comprising a ramp assembly secured to said front portion of said frame, said ramp assembly including a plurality of lifting tines extending forwardly of said first cutting blade.

6. A roof membrane and insulation removing device, comprising:

a frame having a front portion and a rear portion capable of relative pivoting motion about a substantially horizontal axis, said front portion being supported by a first pair of wheels and said rear portion being supported by a second pair of wheels,

a pair of rearwardly extending handlebars being secured to said rear portion of said frame;

a first pair of circular cutting blades being secured side-by-side to said front portion of said frame, said first pair of circular cutting blades being coplanar, and each one of said first pair of circular cutting blades being rotatable about a substantially vertical axis;

a second pair of circular cutting blades being secured to opposite sides of said front portion of said frame forwardly of said first pair of cutting blades, each one of said second pair of circular cutting blades being rotatable about a substantially horizontal axis;

a first hydraulic motor being secured to said rear portion of said frame for rotating said second pair of wheels;

a second hydraulic motor being secured to said front portion of said frame for rotating said first pair of circular cutting blades; and,

a second hydraulic motor being secured to said front portion of said frame for rotating said second pair of circular cutting blades.

7. The roof membrane and insulation removing device according to claim 6 further comprising a ramp assembly secured to the front of said wheeled frame, said ramp assembly including a plurality of lifting tines extending forwardly of said first cutting blade.