Abstract:
A snow plow for use with personal utility vehicles is disclosed. The snow plow includes a mounting apparatus for attachment to a vehicle and a plow blade having a main surface, a rear surface, a plurality of retention members and a rubber scraper. The mounting apparatus includes a frame having a mounting upright and a hitch tongue, which is easily mounted in a hitch receiver which can be pivotally secured a vehicle. The retention members configured to at least partially encircle and slideably engage the mounting upright when the plow blade is in a working orientation. Preferably, the frame pushes the rear surface of the plow blade when the vehicle is moving in a direction towards the plow blade and wherein the frame disengages the rear surface when the vehicle moves in a direction rearward of the plow blade and the plow blade pivots away from the frame.

Description:
RELATED APPLICATIONS  
       [0001]     The present application is related to and claims priority to U.S. patent application Ser. No. 10/990,148, filed Nov. 15, 2004, which claims priority to co-pending U.S. patent application Ser. No. 10/841,740, filed May 7, 2004 both entitled SELF-ADJUSTING SNOW PLOW, both of which claim priority to U.S. patent application Ser. No. 10/404,164, filed Mar. 31, 2003, which issued as U.S. Pat. No. 6,817,118 for SELF-ADJUSTING SNOW PLOW on Nov. 16, 2004, all of which claim priority to PCT application No. PCT/US01/47125 for SELF-ADJUSTING SNOW PLOW, filed Nov. 12, 2001, and each of which are hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to adjustable snow plows for attachment to personal utility vehicles such as pickup trucks and sport utility vehicles. More particularly, the present invention relates to adjustable snow plows that are attached to personally utility vehicles with a hitch tongue connecting member.  
       BACKGROUND OF THE INVENTION  
       [0003]     Moving snow off of open ground, streets, sidewalks and parking lots is an age-old problem in less temperate climates where significant snowfall is anticipated during colder periods of the year. For instance, in many parts of Canada and in many northern states in the United States, significant snowfall can be expected during the late fall and early-to-mid winter months. Snowfall in some of these areas is also possible in early spring.  
         [0004]     Clearing freshly fallen snow from open ground, parking lots, driveways, sidewalks and roadways, whether these surfaces are paved or not, is a task common to all of these areas that is generally required to make these surfaces passable. If the snow is allowed to accumulate over a period of weeks, the snow eventually makes the use of these surfaces for pedestrian and vehicular travel difficult, if not treacherous. Therefore, many devices have been designed and manufactured to remove accumulated snow from such surfaces. Municipalities generally use large vehicles with enormous snow plows to clear paved roadways used by the public and states in these areas also generally have a fleet of these vehicles to clear snow from such roadways and from large parking lots on state-owned properties. However, the purchase and use of such a vehicle by individuals, who have a need to move accumulated snow in smaller areas, is less feasible. First of all, the larger vehicles are expensive to purchase and maintain and are, in some cases, dedicated solely to the removal of accumulated snow. It will be appreciated that it would not be cost effective for an individual to purchase, house and maintain such a vehicle for removing snow from driveways and smaller parking lots during a limited period of the year.  
         [0005]     For this reason, many inventors have designed and manufactured adjustable snow plows that can be attached to pickup trucks and other vehicles for a period of time during the year when snow removal is required. In this way, the vehicles can be used for other purposes during periods when snow removal is not required. Many of the snow plows attached to these vehicles, however, are large and heavy and are not easily attached and removed from the vehicles. A number of snow plows have been invented that attempt to address these problems. For instance, Kowalczyk (U.S. Pat. No. 4,944,104) discloses a detachable snow plow assembly that is pivotally attached to a common passenger vehicle. In one embodiment of the invention, the snow plow includes rollers secured within channels attached to mounting uprights to allow the plow blade to ride up and down when the blade comes into contact with irregularities in the surface. The plow blade can also pivot forward along with the mounting uprights in certain embodiments when the vehicle is moving backward allowing the plow blade to pivot forward over the ground. In other disclosures, such as the snow plow assembly disclosed by Rosenberg (U.S. Pat. No. 5,136,795) a trip mechanism is disclosed which allows the lower part of the plow blade to pivot backward when the plow blade comes into contact with relatively immovable objects and the trip mechanism is actuated. Rosenberg also discloses a rubber scraper at the bottom of the plow blade which is secured between two metal plates and oriented at an angle rearward of a vertical orientation. Rubber scrapers are also disclosed on older snow plows, such as the snow plow mold board disclosed by C. H. Wagner (U.S. Pat. No. 3,477,149), which discloses a resilient scraping blade made of rubber. This is a common feature in many snow plows, allowing the rubber scraper to contact the ground and provide a somewhat more forgiving surface with which to contact the ground when the plow is used to remove accumulated snow, but the rubber scraper is generally accompanied by a metal backing.  
         [0006]     Although each of these has its own advantages, none of them are easy to attach and remove from the vehicle once attached. They also tend to be heavy and cumbersome, and at least somewhat unsightly. The present invention provides a more cost effective and attractive snow plow for removing smaller amounts of accumulated snow from driveways and small-to-medium sized parking lots where one individual may wish to use his or her vehicle to remove snow during a relatively limited period of time, while still having use of the vehicle for other purposes not involving snow removal, when the snow plow must either be removed or placed in a suitable position for non-snow removing transit. The present invention provides solutions for these and other problems associated with the prior art devices for removing accumulated snow and methods used to accomplish the same.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention provides a self-adjusting snow plow for attachment to a vehicle in such a manner to permit the snow plow to make position adjustments when, during use when the vehicle is in motion, a portion of the snow plow comes into contact with a mass of snow or other objects on the ground, upon which the vehicle travels when in motion, that are relatively immovable. The self-adjusting snow plow preferably includes a mounting apparatus for attachment to the vehicle and a plow blade. The mounting apparatus preferably includes a mounting frame having first and second mounting uprights and the plow blade has first and second ends, a top, a bottom, a main surface, a rear surface, a retention member and a rubber scraper preferably secured to the bottom of the plow blade. Preferably, the frame pushes the rear surface of the plow blade when the vehicle is moving in a direction towards the plow blade and the frame disengages the rear surface when the vehicle moves in a direction rearward of the plow blade and the plow blade pivots away from the frame. Preferably, the mounting apparatus will further include hitch tongue securable to the vehicle. Additionally, the preferred mounting apparatus includes a pivotal hitch assembly which can be secured to place the plow blade at an angle to a plane perpendicular to a line parallel to a forward direction of the vehicle.  
         [0008]     The preferred plow blade will include first and second retention members. In these embodiments, the retention members are constructed and arranged to at least partially encircle one of the respective mounting uprights when the plow blade is engaged with the mounting apparatus in a working orientation such that the plow blade is in contact with the ground or objects on the ground. The respective retention members are slidably engaged with the respective mounting uprights when the plow blade is engaged with the mounting apparatus in a working orientation. When the plow blade comes into contact with a mass of snow or other objects on the ground that are relatively immovable, the respective retention members can slide upward along the respective mounting uprights to enable either or both of the respective ends of the plow blade to slide upwardly relative to the mounting upright most proximate to that end of the plow blade.  
         [0009]     The retention members also permit the bottom of the plow blade to freely pivot away from the respective mounting uprights when the plow blade is engaged with the mounting apparatus in a working orientation and the vehicle is in motion in a direction rearward of the plow blade. In preferred embodiments, the rubber scraper secured to the bottom of the plow blade is a resilient elastomeric member having a resting orientation in which the rubber scraper extends downwardly and away from the bottom of the plow blade at an angle which extends forward from a plane which extends along a main surface of the plow blade. In preferred embodiments, the rubber scraper is preferably about an inch thick and extends away from the plow blade at least about three and one-half inches. In alternate embodiments having a single retention member, the retention member is alternatively constructed and arranged to either encircle or partially encircle both of the mounting uprights.  
         [0010]     It is the primary objective of the present invention to provide a method of clearing accumulated snow from the surface of driveways, parking lots and other similar areas where snow removal is essential during the winter months.  
         [0011]     It is an additional objective of the present invention to provide such an apparatus that can be easily mounted and removed from the front end of pickup trucks, sport utility vehicles and other commonly used vehicles.  
         [0012]     It is a further objective of the present invention to provide such an apparatus for snow removal that is much simpler to install and use then other similar devices commonly found in the market today.  
         [0013]     It is a further objective of the present invention to provide such an apparatus for snow removal which includes a plow blade which is relatively light and allows an individual person to lift respective ends of the plow blade in order to lower them into position for clearing snow or to lift the respective ends of the plow blade to secure the blade in position for transit.  
         [0014]     It is a further objective of the present invention to provide such an apparatus for snow removal that does not require the owner of the vehicle to purchase separate running lights for the vehicle in order to use the self-adjusting snow plow.  
         [0015]     It is yet another objective of the present invention to provide such an apparatus for snow removal that easily slides upward on a mounting apparatus to allow the plow blade to go up and over immovable objects encountered during use.  
         [0016]     It is yet another objective of the present invention to provide such an apparatus for snow removal that allows the operator to drive in reverse after moving snow off of a flat surface, wherein the plow blade is hinged so that the blade “floats” freely on a pair of mounting uprights and can slide up and down independently on the mounting uprights and the lower portion of the plow blade can pivot forward with respect to the mounting uprights allowing the vehicle to easily draw the plow blade in reverse.  
         [0017]     It is yet another objective of the present invention to provide such an apparatus for snow removal that lifts the rubber scraper at the bottom of the plow blade off the ground when the vehicle draws the plow blade in reverse and the lower portion of the plow blade pivots forward with respect to the mounting apparatus.  
         [0018]     It is still a further objective of the present invention to provide such a method that does not employ the use of expensive and heavy hydraulic systems that are common used in such devices today.  
         [0019]     These objectives are preferably accomplished by the use of a common hitch receiver that is attached to (and extends forward from) the front end of the vehicle that is to be used in the plowing operation. This receiver hitch preferably provides a mounting point which is a socket for the mounting apparatus, which is accomplished by inserting a tongue of the plow hitch into the hitch receiver and then locking it into place with a pin. This forms a solid mounting for the present invention that allows it to be quickly and easily attached to the front end of any vehicle. A primary advantage of this invention is that it does not require that a user keep the plow assembly on the plow vehicle for the entire season. Its ease of use is also a primary advantage as is its moderate cost.  
         [0020]     These and other objectives and advantages of the invention will appear more fully from the following description, made in conjunction with the accompanying drawings wherein like reference characters refer to the same or similar parts throughout the several views. And, although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structure. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]     In the drawings, in which corresponding reference numerals and letters indicate corresponding parts of the various embodiments throughout the several views, in which the various embodiments generally differ only in the manner described and/or shown;  
         [0022]      FIG. 1  is a side elevation of a preferred embodiment of the present invention showing a self-adjusting snow plow attached to a vehicle (shown in phantom). The plow blade is shown in phantom in an elevated position;  
         [0023]      FIG. 2  is a partial side elevation of the self-adjusting snow plow shown in  FIG. 1  showing the plow blade in a position in which the bottom (not shown) of the plow blade is pivoted forward so that the preferred retention member may be disengaged from the mounting upright and placed in the attachment member so that the plow blade can reside in a non-working transit orientation shown in  FIG. 3 ;  
         [0024]      FIG. 3  is a partial side elevation of the self-adjusting snow plow shown in  FIGS. 1 and 2 , but showing the plow blade in the non-working transit orientation;  
         [0025]      FIG. 4  is a front elevation of an alternate self-adjusting snow plow; the plow blade is shown in a working orientation and is shown in phantom in further working orientations when one end or the other is raised with respect to the mounting uprights;  
         [0026]      FIG. 5  is a top elevation of the self-adjusting snow plow shown in  FIG. 4 ;  
         [0027]      FIG. 6  is a top elevation of a further embodiment of the self-adjusting snow plow of the present invention showing a plow blade in phantom which is the same as that shown in  FIG. 5 , but showing an alternate mounting apparatus having a pivotal hitch assembly which can be secured to place the plow blade at an angle to a plane perpendicular to a line parallel to a forward direction of the vehicle (not shown);  
         [0028]      FIG. 7  is an exploded perspective view of the preferred self-adjusting snow plow shown in  FIGS. 1-3 ;  
         [0029]      FIG. 8  is a cross-sectional view of the preferred plow blade shown in  FIG. 7  as seen from the line  8 - 8  of  FIG. 7 ;  
         [0030]      FIG. 9  is a side elevation of the alternate self-adjusting snow plow shown in  FIGS. 4 and 5  illustrating how the plow blade slides upwardly with respect to the mounting uprights when it moves forward and comes into contact with a relatively immovable object on the ground, wherein the drawing illustrates in phantom the plow blade in a working orientation as it is moving forward toward such a relatively immovable object and also showing the plow blade once it has moved upward with respect to the mounting uprights after the rubber scraper has come into contact with such a relatively immovable object;  
         [0031]      FIG. 10  is a side elevation of the alternate embodiment of the self-adjusting snow plow shown in  FIGS. 4-5  and  9  showing how the bottom of the plow blade pivots outward away from the mounting uprights when the vehicle (not shown) to which the self-adjusting snow plow is attached, moves backward drawing the plow blade with the vehicle;  
         [0032]      FIG. 11  is a side elevation similar to that shown in  FIG. 10 , but showing the preferred plow blade shown in  FIGS. 1-3  when the vehicle (not shown) moves backward drawing the preferred plow blade with it in a manner which allows the bottom of the plow blade to pivot forward, away from the mounting uprights;  
         [0033]      FIG. 12  is a partial side elevation of an alternate plow blade having an alternate rubber scraper;  
         [0034]      FIG. 13  is a further partial side elevation of an alternate plow blade showing a further alternate rubber scraper;  
         [0035]      FIG. 14  is a side elevation of a portion of a further alternate embodiment of the present self-adjusting snow plow showing an alternate catch structure at the upper end of the mounting upright which also includes an alternate attachment member including a removable pin with which to secure the retention member within the attachment member;  
         [0036]      FIGS. 15 and 16  are top elevation views of alternate retention members;  
         [0037]      FIG. 17  is a side elevation of the alternate retention member shown in  FIG. 15 ;  
         [0038]      FIG. 18  is a top elevation of a further alternate retention member, which is pivotally secured to the alternate plow blade;  
         [0039]      FIG. 19  is a side elevation of the alternate retention member shown in  FIG. 18 ;  
         [0040]      FIG. 20  is a front elevation of an alternate self-adjusting snow plow; similar to that shown in  FIG. 4  where the plow blade is shown in a working orientation and is shown in phantom in further working orientations when one end or the other is raised with respect to the mounting uprights, but the plow includes alternate first and second retention members, each of which just partially encircles one of the respective mounting uprights;  
         [0041]      FIG. 21  is a front elevation of an alternate self-adjusting snow plow; similar to that shown in  FIG. 4  where the plow blade is shown in a working orientation and is shown in phantom in further working orientations when one end or the other is raised with respect to the mounting uprights, but the plow includes further alternate first and second retention members, each of which just partially encircles one of the respective mounting uprights;  
         [0042]      FIG. 22  is a front elevation of an alternate self-adjusting snow plow; similar to that shown in  FIG. 4  where the plow blade is shown in a working orientation and is shown in phantom in further working orientations when one end or the other is raised with respect to the mounting uprights, but the plow only includes a single retention member which encircles both of the mounting uprights; and  
         [0043]      FIG. 23  is a front elevation of an alternate self-adjusting snow plow; similar to that shown in  FIGS. 4 and 22  where the plow blade is shown in a working orientation and is shown in phantom in further working orientations when one end or the other is raised with respect to the mounting uprights, but the plow includes an alternate retention member, which just partially encircles each of the mounting uprights. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0044]     Referring now to the drawings, and more particularly  FIGS. 1-3 , a preferred self-adjusting snow plow  10  of the present invention is shown. The preferred snow plow  10  includes a mounting apparatus  14  and a plow blade  30 . Referring now also to  FIGS. 7 and 8 , the preferred mounting apparatus  14  includes a hitch receiver  16  which is secured to a vehicle  18  (partially shown in phantom in  FIG. 1 ). The mounting apparatus  14  also includes two mounting uprights  20  that are interconnected by an interconnecting member  22 . In this embodiment, a hitch tongue  24  is secured to the interconnecting member  22  by a series of bolts  25  secured by nuts  26 . The bolts  25  secure the hitch tongue  24  to the interconnecting member  22  with a resilient rubber connecting member  27  interspersed between the interconnecting member  22  and a flat connecting plate  28  of the hitch tongue  24 . A securing pin  29  secures the hitch tongue in the mounting point of the hitch receiver  16 . The resilient rubber connecting member  27  allows the entire snow plow  10  some flexibility when the plow blade  30  is subjected to great forces. This reduces the shock and vibration in the vehicle due to impacts against relatively immovable objects.  
         [0045]     The preferred plow blade  30  includes a mold board  32  providing a channel  34  in which a rubber scraper  36  is secured. The preferred mold board  32  is a single piece aluminum extrusion, although other materials may be used. The plow blade  30  also includes two retention members  38  and a plurality of lifting handles  40 . The preferred plow blade  30  has enlarged end caps  46  secured at each end if the plow blade with blade cap securing plates  48 . In preferred embodiments, the end caps  46  and the rubber scraper  36  are made of resilient elastomeric materials such as hardened natural rubbers and other synthetic materials, which have been used commercially to replace such products. In preferred embodiments, this material can be Styrene-Butadiene rubbers (SBR), butylene rubber (a copolymer of isobutylene and isoprene), Acrylonitrile-Butadiene rubbers (NBR), neoprene, Thiokol® rubbers and the like; preferably SBR. In the most preferred embodiment SBR  60  Durometer rubber is used. It will be appreciated that the term “rubber”, when used to describe the various embodiments of the scraper  36  or the end cap  46 , is used in a general sense and is not meant to limit the material used to construct the scraper  36  or the end cap  46  solely to rubber, but that it will also mean the aforementioned elastomers and other like materials.  
         [0046]     Referring now also to  FIGS. 4 and 5 , a further alternate embodiment of the plow blade  30 ′ is shown in which the end caps  46 ′ are metal sheets the size of and similar to the blade cap securing plates  48  of the previously discussed preferred embodiment. These end caps  46 ′ do not extend beyond the bottom  60 ′ of the mold board  32 ′. It will be appreciated that the embodiment shown in  FIGS. 1-3 ,  7  and  11  can be modified by removing the end caps  46  and simply replacing them with the end cap securing plates  48 , which take their place and become the replacement end caps as used in the alternate embodiments shown in  FIGS. 4-5  and  8 . With the exception of the different end caps  46 ,  46 ′, everything else about these embodiments is generally the same.  
         [0047]     Referring now also to  FIG. 6 , an alternate mounting apparatus  14 ″ is shown in which the mounting uprights  20 ″ are secured to an interconnecting member  22 ″ which is joined to a pair of generally identical plates  42 , only one of which is shown, which sandwich and are pivotally connected with the alternate hitch tongue  24 ″ by a pivot pin  77 . A removable lock pin  21  is used to secure the plates  42  in one position or another (as shown in phantom) by removing the lock pin  21  and turning the blade  30 ″ so that holes  78  (shown only in the upper plate shown in  FIG. 6 ) in the plates  42  and the hitch tongue  24 ″ (not shown) will align after the mounting uprights  20 ″ and the plow blade  30 ″ are turned sufficiently to allow the respective lock pin receiving holes in the plates  42  and the hitch tongue  24 ″ to be aligned. The plow blade  30 ′ of the second embodiment shown in  FIGS. 4-5  and  8  has been found to be somewhat more effective than the preferred plow blade  30  (shown in  FIGS. 1-3 ,  7  and  11 ) when the plow is pivoted in either direction to push snow to one side or the other of the vehicle  18 , because the larger end caps  46  of the preferred embodiment are not used. This makes it easier for snow to slide off of one end of the plow blade  30 ′,  30 ″ or the other when the plow blade is being pushed forward. It is possible to address this potential enhancement by simply removing the end cap  46  from one end of the preferred plow blade  30 , when it is used with the alternate mounting apparatus  14 ″, in which case the end cap  46  at the end which is tilted backwards will be the one which is removed and replaced by the end cap securing plate  48 .  
         [0048]     In  FIG. 1 , the preferred plow blade  30  is shown in a working orientation in which the retention members  38  encircle the mounting uprights  20 . As force is applied to the plow blade  30  and the rubber scraper  36 , the rubber scraper has a tendency to bend backward at its lowest extremities most removed from the mold board  32 . In this way, the force on the lower part of the rubber scraper can have the effect of lifting the plow blade  30  and forcing it to slide upward along the mounting uprights until the retention member strikes the catch structure  50  at the upper end  52  of the mounting uprights  20  as shown in phantom in  FIG. 1 .  
         [0049]     Referring now also to  FIG. 9 , which shows the alternate embodiment shown in  FIGS. 4 and 5 , it is noted that this will also occur when the rubber scraper  36 ′ comes into contact with a relatively immovable object  54  along the ground  56  such as a curb. As shown in  FIG. 1 , the rubber scraper  36  will also bend backwards at the lower extremities when it is pushing a mass of accumulated snow  58 .  
         [0050]     Referring now also to  FIG. 10 , when the vehicle  18  (not shown) is placed in reverse and the plow blade  30 ′ is drawn backwards, the bottom  60  of the plow blade  30 ′ will naturally pivot away from the mounting uprights  20 ′ because the plow blade  30 ′ is only secured at the top  62  by the retention members  38 ′.  
         [0051]     Referring now also to  FIG. 11 , in which the preferred adjustable snow plow  10  and the preferred plow blade  30  are shown, when this embodiment of the plow blade  30  is drawn backwards when the vehicle  18  (not shown) goes in reverse, the rubber scraper  36  is raised above the ground  56  because the end caps  46  extend well beyond the bottom of the mold board  32  and the channel  34  provided by the mold board  32  for the rubber scraper  36  which permits snow and gravel and debris to pass below the rubber scraper  36  when the plow blade  30  is drawn backwards. This is advantageous in certain situations in which there is a desire not to draw snow backwards with the plow blade. When using other devices, it is also necessary to lift the plow blade  30  so as to not draw snow backwards when taking the vehicle in reverse. In this case, however, the extension to the plow blade  30  provided by the end caps  46  raises the bottom of the mold board  32  and the rubber scraper  36 , which extends away from the mold board  32  at an angle. Referring now also to  FIG. 8 , this angle, angle a 1 , relative to a plane  64  of the main surface  66  of the plow blade  30 ′ is at least about 10°, preferably at least about 20°, more preferably at least about 25°, even more preferably at least about 30°, even more preferably at least about 32° and most preferably at least about 32.5°. In preferred embodiments, the end caps  46  extend below the mold board  32  a distance d 3 . In preferred embodiments, this distance is at least about two inches, preferably at least about 2.5 inches, more preferably at least about three inches, and most preferably at least about 3.5 inches, and even more preferably at least about four inches.  
         [0052]     Referring now specifically to  FIG. 8 , in preferred embodiments, the rubber scraper  36 ,  36 ′ is skirtboard rubber which has a thickness, d 1 , in a range from about 0.5 to about two inches, preferably about 0.625 to about 1.75 inches and more preferably from about 0.75 inches to about 1.5 inches. In the most preferred embodiments, the thickness of the rubber scraper  36 ,  36 ′ is about one inch and it is made of SBR rubber having a hardness of about 60 although it may be more or less than 60 depending on the nature of the environment in which it will be used and other considerations, including wear resistance, speed of use and the like. The length of the rubber scraper  36 ,  36 ′ designated by line d 4  is preferably in a range from about four to about ten inches, more preferably from about five to about nine inches, even more preferably from about six to about eight inches. In the most preferred embodiments, the length of the rubber scraper  36 ,  36 ′ will be about six and one-half inches. In preferred embodiments, the length, d 2 , of the amount of the rubber scraper  36 ,  36 ′ which extends beyond the bottom of the mold board  32 ,  32 ′ of the plow blade  30 ,  30 ′ is preferably from about three to about seven inches, more preferably from about four to about six inches, most preferably about five inches. In preferred embodiments, the length of the rubber scraper  36 ,  36 ′ which extends beyond the bottom of the mold board  32 ,  32 ′ is at least about two and one-half inches, preferably at least about three inches, more preferably, at least about three and one-half inches, even more preferably at least about four inches, and even more preferably, at least about four and one-half inches, most preferably at least about five inches.  
         [0053]     Referring now also to  FIG. 12 , a further embodiment of the rubber scraper  36 ″ is shown. In this embodiment, the rubber scraper  36 ″ is made up of two separate sheets of skirtboard rubber that are secured together side by side within the channel  34 ″ of the mold board  32 ″.  
         [0054]     Referring now also to  FIG. 13 , a further alternate embodiment of the rubber scraper  36 ′″ is shown in which the backside of the rubber scraper  36 ′″ includes a slight bevel  68  or chamfer at the lower end  70  of the rubber scraper  36 ′″.  
         [0055]     Referring now again specifically to  FIGS. 2 and 3 , the plow blade  30  may be moved from a working orientation similar to that shown in  FIG. 1  to a non-working transit orientation or position shown in  FIG. 3  by raising one end of the plow blade  30  to the upper end  52  of the mounting upright, swinging the bottom  60  of the plow blade outward and away from the mounting upright  20  to permit the retention member  38  to slide over the catch structure  50  and be lowered into the attachment member  51  where it can be retained as shown in  FIG. 3 . After this has been done at one end, the same process can be followed to lift the opposite end of the plow blade  30  off of the mounting upright  20  so that the retention member  38  can be placed in the attachment member  51  in a manner similar to that shown in  FIG. 3 . Once both retention members  38  are retained within the attachment members  51  at the upper ends  52  of each of the mounting uprights  20 , the plow blade  30  is in a non-working, transit orientation in which the plow blade  30  is not in contact with the ground and the vehicle may be used for purposes other than moving accumulated snow or other materials.  
         [0056]     It is just as easy for a single individual to lower the plow blade  30  into a working orientation when it is in a non-working transit orientation. To lower the plow blade  30  into a working orientation, the individual can lift the retention member  38  out of the attachment member  51 , swing the bottom  60  of the plow blade outward so as to generally pivot it away from the mounting upright  20 , then lower the retention member  38  over the upper end  52  of the mounting upright  20  and allow the retention member to slide down the mounting upright  20  until the lower extremity of that end of the plow blade  30  comes into contact with the ground  56 . Once the first end is in contact with the ground, the user can lift the opposite end in a similar manner, swinging the bottom  60  of the plow blade  30  outwardly so as to pivot the bottom  60  of the plow blade  30  away from the mounting upright  20 , so that the remaining retention member  38  can be first of all disengaged from the attachment member and then lowered over the upper end  52  of the mounting upright  20  until the lower extremity of the remaining end of the plow blade  30  comes into contact with the ground. At this point, the plow blade  30  will be in a working orientation in which it may be pushed by the mounting apparatus to gather and remove snow or other particulate matter on the surface of the ground  56 .  
         [0057]     When the plow blade  30  is lowered into the working orientation, it operates simply when the vehicle moves forward and the mounting uprights  20  push the plow blade  30  forward in a manner which will generally cause the resilient rubber scraper  36  to bend at its lowest extremities in the manner shown in  FIG. 1 . When the alternate mounting apparatus  14 ″ is used to tilt one end of the plow blade  30 ″ back, the mounting uprights  20 ″ still push the blade  30 ″ and the retention members  38 ″ hold the blade  30 ″ in place in front of the mounting apparatus  14 ″.  
         [0058]     Referring now to  FIG. 4 , occasionally, the plow blade  30 ′ will encounter greater resistance either to a mass of snow or other relatively immovable object on one side or the other, causing one end of the plow blade  30 ′ or the other end of the plow blade  30 ′ to ride up on the mounting upright  20 ′ most proximate that particular end of the plow blade  30 ′, as shown in phantom in  FIG. 4 . Because the retaining members  38  have openings  75  which are significantly larger than the mounting uprights  20 ′, the plow blade  30 ′ can ride up on one end or the other until retention member  38 ′ is stopped by the stop structure  50  at the upper end of the respective mounting upright  22 ′.  
         [0059]     It will be appreciated that the retention members  38 ,  38 ′ are designed and constructed to provide an opening  75  which is large enough to allow a person to lift one end of the plow blade  30 ,  30 ′ up and disengage the retention member  38 ,  38 ′ from the respective mounting upright with which it is engaged when it is in a working orientation at the same time, however, the opening  75  has been designed and constructed and secured to the mold board  32 ,  32 ′ of the plow blade  30 ,  30 ′ is a manner which will not allow the retention member  38 ,  38 ′ to slide all the way to the upper end  52 ,  52 ′ of the mounting upright  20 ,  20 ′ without eventually striking the stop structure  50 , which will prevent the plow blade  30 ,  30 ′ from disengaging from the mounting uprights  20 ,  20 ′ unless the bottom  60 ,  60 ′ of the plow blade  30 ,  30 ′ is pivoted away from the mounting uprights  20 ,  20 ′.  
         [0060]     Referring now also to  FIG. 14 , in a further alternate embodiment of the snow plow  10 ″″, the retention members  38 ″″ are stopped by a pin  80  which is secured within an alternate attachment member  51 ″″. In this embodiment, the pin  80  must be removed in order to lift the retention member  38 ″″ off of the upright  20 ″″ and place the retention member  38 ″″ within the attachment member  51 ″″. Once the retention member is placed within the receiving opening  82  of the attachment member  51 , the pin can be secured within openings (not shown) in the respective sides of the attachment member  51 ″″ and a bale or spring wire  84  can be secured over an end of the pin  80  to secure the pin  80 . Although not shown, a spring loaded ball bearing pin (not shown) can also be used in such an attachment member  51 ″″.  
         [0061]     Referring now also to  FIGS. 15-17 , retaining members  84 ,  84 ′ are shown which differ significantly from the retention members  38 ,  38 ′,  38 ″,  38 ′″ and  38 ″″. These retaining members  84  at least partially encircle the mounting uprights  20 . As seen in  FIG. 15 , the retaining member  84  completely encircles the mounting upright  20  and is pivotally interconnected with the alternate mold board  32 ″″ by a securing loop  86 , which is welded to the top of the mold board  32 ″″. In  FIG. 16 , a similar retaining member  84 ′ is shown in which the retaining member  84 ′ only partially encircles the mounting upright  20 .  
         [0062]     Referring now also to  FIGS. 18 and 19 , a further retaining member  84 ″ is shown, which has a larger opening  75 ″, thereby giving the mounting upright  20  greater latitude when moving side to side within the opening  75 ″. This retaining member  84 ″ is pivotally attached to a securing plate  88  which is welded to the alternate mold board  32 ′″″″. It will be appreciated that the retaining member  84 ″ may also have an incomplete side similar to that shown in  FIG. 16  for retaining member  84 ′.  
         [0063]     Referring now also to  FIG. 20 , an alternate embodiment of the snow plow  110  is shown having alternate retention members  138  which only partially encircle the mounting uprights  120  when the plow blade  130  is in a working orientation as shown. Referring now also to  FIG. 21 , a further embodiment to the snow plow  110 ′ is shown having further alternate embodiments of the retention members  138 ′, extending in an opposite direction as compared to that shown in  FIG. 20 , but once again only partially encircling the mounting uprights  120 ′ when the plow blade  130 ′ is in a working orientation as shown. Referring now also to  FIG. 22 , a further alternate embodiment of the plow blade  110 ″ is shown in which a single retention member  238  is attached to the plow blade  130 ″. The retention member  238 ′ is shown in a working orientation and encircles each of the respective mounting uprights  120 ″. Referring now also to  FIG. 23 , a further alternate embodiment of the plow blade  110 ′″ is shown in which a single retention member  238 ′ is attached to the plow blade  130 ′″. The retention member  238 ′ is shown in a working orientation and only partially encircles each of the respective mounting uprights  120 ′″. In each of the aforementioned alternate snow plow embodiments, the plow blade may be disengaged from the respective mounting uprights one upright at a time or, as is also the case with each of the other aforementioned embodiments, the plow blades may be disengaged from the mounting uprights at the same time if both ends of the plow blade are lifted and disengaged at the same time.  
         [0064]     Referring now also to  FIG. 22 , a further alternate embodiment of the snow plow  110 ″ is shown having a single retention member  238  which encircles both of the mounting uprights  120 ″ when the plow blade  130 ″ is in a working orientation as shown.  
         [0065]     In preferred embodiments, the mold board  32  of the plow blade  30  is a hollow extruded aluminum structure. In the most preferred embodiments, the aluminum surface will be clear anodized aluminum which is particularly attractive for consumers. Although the mold board can be extruded into two pieces which are subsequently assembled, the preferred embodiment is a one-piece extrusion which saves both on cost for aluminum and on cost for assembling the mold board. In preferred embodiments, the plow blade will weigh less than about 150 pounds, preferably about 110 pounds. The entire snow plow  10  including the mounting apparatus will preferably weight about 250 pounds, more preferably about 225 pounds.  
         [0066]     When force is applied to the rubber scraper  36  of the present invention, the bottom of the rubber scraper  36  will bend backwards as shown in  FIG. 1  and in  FIG. 9  in reference to the alternate embodiment  30 ′. The rubber scraper  36  will generally bend at a generalized pivot point  81 ′ which is located just below the edge of the channel within the mold board  32 . In softer rubbers having a durometer of 40 or 50, the rubber scraper  36  tends to bend more. For that reason, harder rubbers having a durometer of at least 60, perhaps as much as 70 or 80, are preferred.  
         [0067]     When installing the mounting apparatus, it is easiest to install the mounting uprights  20  in a perfectly vertical position as this is easiest to corroborate if a carpenter&#39;s level is available for use during the installation. It is possible, however, to tip the mounting uprights either forward or backward a small amount. When the uprights are tipped backward, the plow blade tends to rise somewhat more easily when it comes into contact with moveable objects, including accumulated snow on the ground. When the uprights are tipped slightly forward, this tends to put pressure on the rubber scraper  36  and it is believed that the plow blade  30  will not rise up on the mounting uprights  20  quite as easily as it will when the mounting uprights are perfectly upright. In certain embodiments, however, it may be desirable to tilt the uprights forward about two and one-half degrees from vertical. This will allow the rubber scraper to flex to a higher degree and appears to have a shock dampening effect during snow removal. Also, because the mounting uprights are tilted forward, it has an added effect of keeping the blade down when it is in use. In certain situations, this is most desirable as a user may be able to obtain superior results when the blade rises somewhat less readily or when the scraper comes under a lower degree of force. In this regard, it is also noted that the rubber scraper needs to extend outward in front of the mold board. It is believed that if the rubber scraper were straight up and down, the blade would lift up too easily and the snow would squirt under the blade  30  and result in poor snow removal. It is also noted that the rubber end caps will tend to bow outwardly even as great as 90 degrees to the direction of the movement of the plow. This is desirable as it allows the blade to catch more snow when moving it. It will be appreciated that the use of the word rubber in the present invention is used to refer to hardened rubber products which are commercially available and which include SBR, IIR, neoprene and the like.  
         [0068]     An alternative embodiment of the present invention, shown in  FIG. 6 , in which the angle of the plow blade  30 ″ can be varied in relation to its direction of travel. This embodiment is a pivoting snow plow  79  and allows the user to discharge snow on either side of the plow vehicle  18 . In this embodiment of the invention, the connection of the hitch tongue  24 ″ to the plow blade  30 ″ is facilitated through the use of a pivot plate  42 . The pivot plate  42  provides the point of attachment for a forward mounted mount bolt  53  which fastens the interconnecting member  22 ″ to the hitch tongue  24 ″ while allowing the plow blade  30 ″ to pivot around it.  
         [0069]     Additionally, the pivot plate  42  is equipped with a plurality of alternate locking holes  78  which, when used in conjunction with the locking pin  21 , are used to lock the pivoting plow  79  into positions that push snow straight ahead, as shown in  FIG. 6 , or to the left or the right as shown in phantom in  FIG. 6 . This allows the user to employ this embodiment of the present invention in a plurality of orientations. The first of these is to lock the pivoting plow  79  in the position in which the plow blade  30 ″ is square in relation to the line of travel. Conversely, to employ the side discharge function, the user simply locks the pin  21  in the desired alternate locking holes  78  to discharge the snow on the desired side of the plow vehicle  18  (not shown).  
         [0070]     The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described herein, the details may be changed without departing from the intended scope of the invention, which is defined by the attached claims.