Patent application title: Plow back blade for snow removal
Paul E. Dimario (Salem, NH, US)
IPC8 Class: AE01H506FI
Class name: Excavating snow or ice removing or grooming by portable device scraper blade
Publication date: 2012-04-05
Patent application number: 20120079749
The disclosure relates to a device and method of use of a plow back blade
for snow removal. The plow back blade is attached to a snowplow or snow
blower to assist with removing snow from areas that are otherwise
difficult to access with conventional snow removal equipment. The plow
back blade is rotatably attached to a snowplow blade at a pivot point.
The plow back blade is engaged into a locked position as the vehicle
moves in reverse to assist with the scraping of ice and packed snow from
pavement. The plow back blade enters a free position as the snowplow
plows in its forward position which also sharpens the plow back blade
lower edge. Furthermore the plow back blade allows additional
applications for snowplows and snow blowers such as dirt leveling.
1. A snowplow comprising: a snowplow blade supported by a support system;
a plow back blade having a support arm rigidly fastened to a scraper
blade; the support arm rotatably connected to the snowplow blade; wherein
the plow back blade is rotatable between a locked position when the
snowplow blade is operated in a reverse direction and a free position
when the snowplow blade is operated in a forward plowing direction;
2. The device of claim 1 wherein the plow back blade is self sharpened when in the free position.
3. The device of claim 1 wherein the plow back blade is biased against the support system in a transport position.
4. The device of claim 1 wherein the scraper blade extends below a bottom edge of the snowplow blade.
5. The device of claim 1 wherein the scraper blade has a concave working surface.
6. The device of claim 1 wherein the scraper blade includes a removeable wear plate.
7. The device of claim 1 also having the scraper blade having a lower edge with a bevel to remove ice as the snowplow blade travels in a reverse direction.
8. The device of claim 1 wherein the plow back blade has a hinge.
9. The device of claim 1 wherein the support arm is an angle iron.
10. A snow blower comprising: a plow back blade attached to an auger housing; a plow back blade having a support arm rigidly fastened to a scraper blade; the support arm rotatably connected to the auger housing; the plow back blade also attached to a lift mechanism; wherein the plow back blade is rotatable between a locked position and a free position using the lift mechanism.
11. A method of plowing snow in a reverse direction comprising: attaching a plow back blade to a snow plow blade; biasing the plow back blade against the snow plow blade into a locked position; plowing material with the plow back blade as the snow plow blade travels in its reverse direction.
12. The method of claim 11 also having the step of sharpening the plow back blade as the snow plow blade travels in its forward direction.
13. The method of claim 11 wherein the plow back blade can be configured in a "V" configuration.
14. The method of claim 11 wherein the plow back blade can be used to level soil.
15. The method of claim 11 also having the step of biasing the snow plow blade into a transport position.
BACKGROUND OF THE INVENTION
 The disclosure relates generally to plows and in particular the present disclosure relates to plow back blades for snow removal.
 The seasonal removal of snow from residential and commercial driveways and parking lots is generally the responsibility of the property owner. Property owners with relatively small surfaces often use their own or hire contractors with snow blowers to remove the snow. Property owners with large paved surfaces often use or hire snowplows for snow removal. Snowplows and snow blowers are well known in the prior art. Snow blowers are generally small self-propelled units that are powered by an engine that also drives wheels or tracks. However they may also be mounted on a small vehicle such as a pickup, ATV or tractor in a similar manner as a snowplow with the auger powered hydraulically or with a separate engine.
 For large residential and commercial properties, due to the need for expensive equipment that is used very infrequently, snowplowing services are often done by specialized commercial contractors. These contractors may have a significant investment in equipment that is used intermittently, infrequently and without much advanced notice during the winter season. Even though winter snowfall is relatively unpredictable, snow removal contractors only have a very limited time to remove the snow from all their clients paved areas.
 After a snowfall, all customers typically want their property cleaned and cleared as quickly as possible. If a contractor takes to long, the contractor will lose the customer, as the customer makes other arrangements for snow removal. Therefore, there is a relatively small window of time for a contractor keep his equipment active and producing revenue. As such, there is a tremendous advantage for efficient snow removal operations. Improvements in efficiency result in more customers being able to be handled by a given vehicle for a given snow event, directly impacting the profitability of the business.
 Snow removal contractors focusing on parking lots, driveways and the like, often use small vehicles such as four wheel drive pickup trucks equipped with a front mounted plow blade in their business. These vehicles are easily driven from site to site and are very efficient at pushing snow to the perimeter of driveways and parking lots while the vehicle is moving forward.
 However, in many situations the snow must be pulled away from obstacles, such as parked or snowed in vehicles, buildings, garages, retaining walls, parking lot islands, and loading docks. In these situations, the operator must either leave a strip of unplowed pavement next to the obstacle or try several one of several ways to remove the snow all of which are somewhat inefficient.
 Leaving a strip of unplowed snow around an obstacle is usually unacceptable to the customer. Doing so typically requires the contractor make a return trip to the site, which is inefficient and costly.
 To remove the snow from near an obstacle typically requires either the operator get out of the vehicle and manually remove the snow next to the obstacle or the operator try to scrape the snow back with the plow.
 Manually removing the snow with a shovel or snow blower is inefficient because it requires the driver to exit the vehicle to simply move the snow to a position where it can then be accessed with the snowplow and the snowplow has to again be used to push the shoveled snow out of the way. This is a relatively inefficient use of the operator's time since it requires extra time to manually remove the snow as well as to re-plow the pavement receiving the manually removed snow.
 Snowplow blades for small vehicles are designed to push snow while driving forward. The snow accumulates in front of the snowplow blade until it either spills over the top or spills off to the side. The front of a typical snowplow is often concave on its vertical surface. This is done to keep the snow from ramping up the front of the blade and overtopping the blade before it is directed off to the side.
 The concave vertical surface on the snowplow blade is also useful for getting underneath compacted snow and ice to provide a cleaner payment. This happens because using a concave vertical surface allows the edge of the snowplow blade to form an oblique angle of greater than 90 degrees with the pavement approaching the plow which allows the snowplow blade to get under and loosen the compacted snow and ice.
 Often hydraulic cylinders are used to pick the blade up as well as to angle the blade in one direction or the other. In some embodiments the blade is hinged to allow the blade to be formed into a "V" shape with the hydraulic cylinders. In some locations, this is called a Split Gull Wing. This allows the vertex or centerline of the plow to be either forward or behind the centerline of the edges of the plow. Having the edges behind the centerline allow the plow to direct snow to both sides of the vehicle. Allowing the center of the plow to be behind the edges will increase the snow carrying capacity of the plow and reduce the snow directed to the sides of the vehicle while the "V" is filling.
 Regardless of the embodiments described above, the snowplow blades and snow blowers are relatively inefficient at removing the snow by operating the vehicle in reverse and trying to scrape the snow back with the back surface of the snowplow blade. The concave vertical surface of the snowplow blade that is needed to clear the ice and snow from the front of the snowplow translates into a convex back surface on the snowplow blade. The convex back surface prevents efficient dragging of the snow away from objects when the snowplow is operated in reverse. In addition, dragging snow with a conventional snowplow is generally ineffective at removing any compacted snow or ice. The convex angle of approach to the snow when the vehicle is operated in the reverse direction simply allows the back of a normal blade to ride over the packed snow. Even on removal of loose snow, the angle of approach leaves a significant residual behind as the bottom of the snowplow is being dragged over and compacting the snow. Additionally, any snow that is collected behind the snowplow quickly ramps over the convex surface of the back of the snowplow.
 For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for alternative snowplow blades particularly with regard to improving the plowing characteristics of a snow plow in its reverse direction.
SUMMARY OF THE INVENTION
 This disclosure is directed toward a plow back blade that is attached to a snowplow blade or a snow blower. The plow back blade is pivotably connected to the snowplow blade at a pivot point. The plow back blade is configured to not interfere with snowplow blade operation when a vehicle is traveling in a forward direction. The plow back blade is configured to engage material to be plowed when the plow is plowing in a reverse direction opposite the forward direction.
 Conceptually a snow blower may be envisioned as a snowplow blade with additional augers, blowers and shielding to throw the snow a distance beyond the edge of the snow blower. Thus this disclosure is relevant to snow removal generally in bi-directional operation. The invention is highly flexible and independent as to specific details as to how the snow is removed in the forward direction. Therefore this disclosure is presented largely using a snowplow as an example while also being generally relevant to snow blowers.
 It is an object of this invention to disclose a plow back blade that will automatically clear snow adjacent to obstructions without having to disembark a vehicle.
 It is an object of this invention to disclose a plow back blade that will remove ice and packed snow when the vehicle is operated in a reverse direction.
 It is an object of this invention to disclose a plow back blade that will reduce the snow overtopping the snowplow by operating synergistically with the snowplow blade as the vehicle operates in the reverse direction.
 It is an object of this invention to disclose a plow back blade that is self sharpening as the vehicle operates in its forward direction.
 It is an object of this invention to disclose a plow back blade will not interfere with the operation of the snowplow as the vehicle operates in its forward direction.
 It is an object of this invention to disclose a plow back blade that may include a hardened steel wear plate.
 It is an object of this invention to disclose a plow back blade that may be readily mounted on a snowplow or snow blower as an aftermarket accessory.
 It is an object of this invention to disclose a plow back blade that may be used to level soil.
BRIEF DESCRIPTION OF DRAWINGS
 FIG. 1 illustrates an elevational cross section plow back blade attached to a snowplow blade on a vehicle plowing in a forward direction.
 FIG. 2 illustrates an elevational cross section plow back blade attached to a snowplow blade on a vehicle plowing in a reverse direction.
 FIG. 3 is a perspective view of an embodiment of the plow back blade.
 FIG. 4 illustrates a hinged embodiment of a plow back blade, according to another embodiment of the disclosure.
 FIG. 5 is a side view showing several of the positions into which the plow back blade may be operated.
 FIG. 6 is an expanded view of a support arm embodiment-using fastener to hold the plow back blade in a transport position.
 FIG. 7 is a cross-sectional view of a scraper blade having a wear plate with a sharp edge.
 FIG. 8 is an elevational view of a snow blower with a plow back blade in locked position.
 FIG. 9 is an elevational view of a snow blower with a plow back blade in a transport position.
DETAILED DESCRIPTION OF THE INVENTION
 Referring to FIG. 1, a snowplow blade 100 is depicted as being attached to the front of a vehicle for plowing snow as the vehicle moves forward. A support system 110 is used to structurally attach the snowplow blade 100 to the vehicle. The support system 100 is also used to transfer forces from the snowplow blade 100 to the frame and suspension of the vehicle. A plow back blade 10 is rotatably attached to the structure of the snowplow blade 110 to provide snow removal ability as a vehicle moves in a reverse direction to allow bi-directional snow removal ability.
 The snowplow blade 100 is typically a steel plate having a front surface 101 and a back surface 102. Typically the snowplow blade 100 is reinforced with a structural member 105 for example, an angle iron, channel or rectangular tubing may be added to minimize bending and deformation of the snowplow blade 100. A plurality of structural members 105 are typically welded to the back surface 102 of the snowplow blade 100. The snowplow blade 100 may be flat along its vertical direction, but is typically curved into a concave vertical surface.
 The limits of the vertical surface are generally defined by a top edge 103 and a bottom edge 104. The bottom edge 104 is generally horizontal to substantially engage a paved surface. The top edge 103 may be generally parallel to the bottom edge 104 or it may be upwardly sloped from the center of the snowplow blade 100 to each end. A sloped top edge 103 helps prevent overtopping of the snow as the snow accumulates and is moved from an interior of the snowplow blade 100 toward an end.
 A support system 110 is used to transfer the weight and forces received by the snowplow blade 100 into the suspension system of the vehicle. The support system 110 may include vertical support hinge 111 as a point of rotation with a lift mechanism 115 such as a hydraulic cylinder 120 to raise and lower the plow in a vertical direction. The support system 110 may also include a horizontal support hinge 112 to provide a rotation point for one or more hydraulic cylinders 120 to rotate the plow in a horizontal direction. The snowplow blade 100 may also be hinged to allow the blade to be changed into various shapes simply by activating the hydraulic cylinders 120. These shapes may include a straight blade that is horizontally rotatable to direct snow toward a side of the vehicle or a "V" shape so that when the vertex of the "V" is in a forward position, the snow is directed toward both sides of the vehicle, or when the vertex of the "V" is directed rearward, the snowplow blade 100 forms a hopper to enhance collection of snow in front of the front of the snowplow blade 100.
 A plow back blade 10 is mounted to the snowplow blade 100 and is located between the vehicle and at least portions of the snowplow blade 100. The plow back blade 10 includes a support arm 60 that attaches the snowplow blade 100 to a scraper blade 20 portion of the plow back blade 10. The support arms 60 are pivotably connected to the snowplow blade 100, preferably at a structural member 105. Therefore the plow back blade 10 to a large extent will generally be lifted and/or positioned by the lift mechanism through the snowplow blade 100.
 The scraper blade 20 may be a heavy flat bar of hardened steel having a working surface 25 facing the front of the vehicle, and a support surface 30 facing the snow plow blade 100. The working surface 25 may be, for example, either flat or concave. In a concave embodiment, preferably the concave surface would be facing towards the vehicle. As shown in FIG. 1, as the vehicle moves forward, the plow back blade 10 has rotated to a free position 12 so that the scraper blade 20 is being pulled or dragged along the pavement. This dragging action may provide a self-sharpening feature to the scraper blade 20.
 With reference to FIG. 2, the snowplow blade 100 is raised sufficiently so that snow plow blade 100 is above the pavement, and the plow back blade 10 is allowed to rotate into a substantially vertical position from the weight of the plow back blade 10. The snowplow blade 100 is then lowered so that scraper blade 20 contacts the pavement surface. If desired, substantially the entire weight of the snowplow blade 100 may be supported by the plow back blade 10. The reverse operation of the vehicle in cooperation with either the physical friction from the pavement and/or the accumulating weight of the snow, will rotate the plow back blade 10 toward the snowplow blade 100 until the plow back blade 10 physically contacts the snowplow blade 100 such as at a structural member 105. The plow back blade is then in its locked position 11 held against the snowplow blade 100 by the reverse movement of the vehicle and the weight of the accumulating snow against the scraper blade 20.
 Since the vertical height of the plow back blade 10 is less than the vertical height of the snow plow blade 100, the snow may overtop the plow back blade 10. This is usually not an issue of concern because reverse operation of the vehicle is not generally necessary to occur over any substantial distance. However, any snow that overtops the plow back blade 10 is very loose and easily captured by the back surface 102 of the snow plow blade 100.
 The plow back blade 10 shown in FIG. 3 includes a scraper blade 20 that may be integral with or attached to support arms 60. The support arm 60 has a free end and a fixed end. By way of example, the support arms 60 shown as an angle iron may also be channel or tube with a circular or rectangular cross section. The support arm 60 may be straight or arced in either a longitudinal or lateral direction. The support arm 60 fixed end is attached to the scraper blade 20 by welding, bolting or other known means. The support arm 60 free end includes a pivot point 65 for pivotably connecting the plow back blade 10 to the structural member 105. Examples of a pivotal connection include a pin, bolt, bearing assembly or rivet. The support arm 60 is typically pivotably attached to a structural member 105 on the back surface 102 of the snowplow blade 100 or directly to the back surface 102, preferably at approximately the vertical midpoint of the snowplow blade 100.
 The working face 25 of the scraper blade 20, facing the vehicle, has an upper edge 21 and a lower edge 22. The upper edge 21 position is determined by the geometry of the support system 110. The upper edge 21 position is located so that it contacts the snowplow blade 100 at its desired locked position and can freely rotate beyond the free position 12 without interference from the support system 110.
 The lower edge 22 is positioned so that the lower edge 22 is at or below the bottom edge 104 of the snowplow blade 100. Otherwise a gap would exist and the plow back blade 10 would be unable to contact all the packed snow on the pavement. If the lower edge 22 is below the bottom edge 104 of the snowplow blade 100, it is possible to place the entire weight of the snowplow blade 100 on the plow back blade 10 which assists with removal of ice and packed snow. Furthermore if the working surface 25 of the plow back blade is concave this is also useful for getting underneath compacted snow and ice to provide a cleaner payment. This happens because using a concave vertical surface allows the working surface 25 forms an oblique angle of greater than 90 degrees with the pavement approaching the plow back blade 25 which allows getting under and loosening the compacted snow and ice.
 FIG. 4 illustrates a hinged embodiment of a plow back blade suitable for use on a hinged plow that is conformable into a "V" configuration. Alternatively, two independent plow back blades 10 could be installed with the plow back blades 10 meeting in the horizontal center of the snowplow blade 100. Also shown in FIG. 4 is an embodiment where the scraper blade 20 includes a wear plate 35. This allows for easy replacement and/or hard surfacing of the lower edge 22 which receives extra wear being in direct contact with the pavement.
 FIG. 5 is a side view showing the rotation of the plow back blade 10 about the pivot point 65 to its range of positions. A substantially horizontal position is utilized as a locked position 11 defined by the plow back blade 10 being held against the snowplow blade 100 as the vehicle travels in a reverse direction. The free position 12 allows the plow back blade 10 to loosely drag and conform to the pavement contours as the vehicle moves in a forward direction. Additionally a transport position 13 may be utilized where the plow back blade 10 is rigidly fastened out of the way when not in use. This position is useful to prevent the plow back blade from swinging when the vehicle is moving but not plowing such as when traveling between sites.
 FIG. 6 shows the support arm 60 held in the transport position 13 using a fastener 45 such as a bolt or pin to prevent the plow back blade 10 from swinging during vehicle movement. Alternatively, the plow back blade could be chained, pinned or otherwise clipped to the snow plow blade 100 or support system 110.
 FIG. 7 shows a cross-sectional view of a scraper blade 20 having a wear plate 35 with a sharp bottom edge. The support surface 30 faces the snow plow blade 100 and is opposite the working surface 25 of the scraper blade 20. As the vehicle operates in its forward direction a bevel is formed between the support surface 30 and the working surface 25. This bevel is self sharpening and useful for assisting scraping of ice and snow as the vehicle moves in a reverse direction.
 As previously described the plow back blade 10 is also suitable for use on snow blowers 200. Snow blowers 200 may be vehicle mounted or self propelled. FIG. 8 is an elevational view of a self propelled snow blower 200 with an auger 210 within an auger housing 220. The plow back blade 10 is in a locked position 11 and attached to the auger housing 220. As shown, the lift mechanism 115 would typically be a simple mechanical linkage.
 FIG. 9 is an elevational view of a snow blower 200 with a plow back blade 10 in a transport position 13.
 With regard to snow blowers 200 and snowplows, a feature of the invention that allows the lower edge 22 of the plow back blade 10 to be below the bottom edge 104 of the snowplow blade 100. In this embodiment it is possible to place the entire weight of the snowplow blade 100 on the plow back blade 10. This feature allows these machines to be used for leveling materials such as dirt, sand and gravel. This is possible because the plow back blade 10 can be easily constructed to handle these materials in a reverse direction even though it would be cost prohibitive and for impractical to utilize these devices in a forward direction on these dense materials. This would allow for example, a snow blower to used in the summer time for leveling fill on small landscaping or construction. For example, a snow blower could be used to assist filling in potholes on a gravel road or path, a use totally impractical with a conventional snow blower.
 Although specific embodiments of apparatuses and methods using the apparatus as an example, have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement, combination, and/or sequence that is calculated to achieve the same purpose may be substituted for the specific embodiments shown. It is to be understood that the above description is intended to be illustrative and not restrictive.
 Combinations of the above embodiments and other embodiments as wells as combinations and sequences of the above methods and other methods of use will be apparent to individuals possessing skill in the art upon review of the present disclosure. The scope of the claimed apparatus and methods should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.
Patent applications in class Scraper blade
Patent applications in all subclasses Scraper blade