Patent Publication Number: US-2003226289-A1

Title: Extendable plow

Description:
BACKGROUND OF THE INVENTION  
       [0001] The present invention relates to an extendable plow, and in particular to an extendable plow having an uninterrupted plowing surface.  
       [0002] Snow plowing in residential and commercial areas has become a large commercial industry, and is practiced by contractors on a seasonal or individual job basis. Plow assemblies are typically designed for attachment to standard vehicles, such as front end loaders and trucks. Lifting and positioning of the plow blade is usually done with hydraulic actuators operated on pressure, generated by a pump driven by the vehicle engine.  
       [0003] Drag plows are often mounted on the rear of an associated vehicle as a supplement to the action of a front-mounted principal plow. In the interest of saving time, these plows have been designed for lateral extension from a retracted central position to an extended position. The conditions under which these plows operate vary greatly, however most applications require simplicity and ruggedness. Further, many applications include snow removal from large areas such as industrial parking lots, multiple lane roads and driveways, etc. Heretofore, these plows have been limited by narrow plowing spans or widths, thereby requiring multiple passes to clear an area, resulting in a loss of productivity.  
       SUMMARY OF THE INVENTION  
       [0004] One aspect of the present invention is to provide an extendable plow that includes a first plow section having a first plowing surface and adapted to be supported by a vehicle, wherein the first plowing surface defines a first width, and second plow section having a second plowing surface and slidably connected to the first plow section. The second plow section and the third plow section are slidable between a retracted position wherein the second plowing surface and the third plowing surface are substantially laterally aligned with the first plowing surface, and an extended position wherein the second plowing surface and the third plowing surface extend laterally beyond the first plowing surface. The first plowing surface, the second plowing surface and the third plowing surface cooperate to form an uninterrupted total plowing surface defining a total width that is substantially double the first width when the second plowing surface and the third plowing surface are in the extended position.  
       [0005] Another aspect of the present invention is to provide an extendable plow that includes a first plow section having a first plowing surface and adapted to be supported by the vehicle, a second plow section having a second plowing surface, and a third plow section having a third plowing surface. The extendable plow also includes a sliding connector slidably connecting the second and third plow section with the first plow section, wherein the sliding connector includes a pair of spaced-apart, horizontally-extending guideways affixed to the first plow section, and a pair of engagement members affixed to the second and third plow sections and received by the guideways. The second and third plow sections are slidable between a retracted position wherein the second and third plow sections are substantially laterally aligned with the first plow section, and an extended position wherein the second and third plow sections extend laterally outward from the first plow section and the first, second and third plow surface cooperate to define an uninterrupted total plowing surface.  
       [0006] The present inventive expandable plow provides a more durable and efficient plow capable of a long operating life, and particularly well adapted for the proposed use. These and other advantages of the invention will be further understood and appreciated by those skilled in the art by reference to the following written specification, claims and appended drawings.  
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0007]FIG. 1A is a front elevational view of an extendable plow embodying the present invention, wherein the plow is in the extended position;  
     [0008]FIG. 1B is a front elevational view of the extendable plow, wherein the plow is in a retracted position.  
     [0009]FIG. 2 is a top plan view of the extendable plow in the extended position and supported by a vehicle;  
     [0010]FIG. 3A is a cross-sectional side view of the extendable plow in a lowered position;  
     [0011]FIG. 3B is a cross-sectional side view of the extendable plow in a raised position;  
     [0012]FIG. 4 is an enlarged view, fragmentary cross-sectional side view of the extendable plow, taken along the line V-V, FIG. 1A;  
     [0013]FIG. 5 is a rear perspective view of the extendable plow in a partially extended position;  
     [0014]FIG. 6 is a rear perspective view of a first alternative embodiment of the extendable plow; and  
     [0015]FIG. 7 is a rear perspective view of a second alternative embodiment of the extendable plow. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0016] For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in FIG. 1A. However, it is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.  
     [0017] The reference numeral  10  (FIGS. 1A and 1B) generally designates an extendable plow embodying the present invention. In the illustrated example, the extendable plow  10  includes a first plow section  12  having a first plowing surface  14  and that is adapted to be supported by a vehicle  16 . The first plowing surface  14  defines a first width between a first end  13  (FIG. 2) and a second end  15 . The extendable plow  10  also includes a second plow section  18  having a second plowing surface  20  and that is slidably connected to the first plow section  12  as described below. The second plowing surface  12  defines a second width between a first end  17  and a second end  19 . The extendable plow  10  further includes a third plow section  22  having a third plowing surface  24  and that is slidably connected to the first plow section  12 , as described below. The third plowing surface  24  defines a third width between a first end  21  and a second end  23 . The second plow section  18  and the third plow section  22  are each slidable in a direction as indicted by directional arrow  26  between a retracted position, wherein the second plowing surface  20  and the third plowing surface  24  are substantially laterally aligned with the first plowing surface  14 , as shown in FIG. 1B, and an extended position, wherein the second plowing surface  20  and the third plowing surface  24  extend laterally beyond the first plowing surface  14 , as shown in FIG. 1A. The first plowing surface  14 , the second plowing surface  20  and the third plowing surface  24  cooperate to form an uninterrupted total plowing surface defining a total width that is substantially double the first width when the second plow section  18  and the third plow section  22  are in the extended position.  
     [0018] The first or central plow section  12  includes a plate  28  (FIGS. 3A and 3B) having a bend  30  located at a midpoint along the height thereof, thereby providing first plowing surface  14  with a forwardly facing, concave cross-sectional configuration. The plate  28  includes the first plowing surface  14  and a rear surface  32 . The first plow section  12  also includes a support bracket assembly  34  adapted to support the first plow section  12  from the vehicle  16  and connected to the rear surface  32  of the plate  28  via welding, riveting, and the like. The support bracket assembly  34  includes a pair of support housings  36  extending rearwardly from the rear surface  32  of the plate  28 , and a pair of vertically extending L-shaped brackets  38  attached to an outer surface of the support housings  36 . The support bracket assembly  34  also includes an upper support bracket  40  extending between the brackets  38 , and angularly and rearwardly from the support housings  36  and forming a gap  42  therewith. The support bracket assembly  34  further includes a lower support bracket  44  extending between the brackets  38  and including a plurality of apertures  46  spaced therealong.  
     [0019] In the illustrated example, the vehicle  16  is provided with a lifting assembly  48  that includes a pair of lift arms  50  and a pair of hydraulic actuators or cylinders  52 . The lift arms  50  are connected to the first plow section  12  at a pivot point  54 , while the cylinders  52  are connected to an engagement mechanism  56  of lifting assembly  48  at a pivot point  58 . The opposite end of each cylinder  52  is pivotally attached to a respective lift arm  50  at a pivot point  60 .  
     [0020] In operation, an engagement bracket  62  of the lifting assembly  48  is engaged within the gap  42  beneath the upper support bracket  40 , while a lower portion of the lifting assembly  48  engages apertures  46  within lower support bracket  44 , thereby attaching the first plow section  12  with the lifting assembly  48  of the vehicle  16 . The extendable plow  10  is operated in a path as illustrated by directional arrow  64  between a lowered position, as illustrated in FIG. 3A, and a raised position, as illustrated in FIG. 3B, by operation of the cylinders  52 .  
     [0021] The first plow section  12  further includes guideways  66 ,  68 ,  70  and  72  affixed to the first plowing surface  14 . Guideways  66 ,  68 ,  70  and  72  are each provided with a square, cross-sectional configuration and include a longitudinally extending, forwardly facing slot  74 . The guideways  66 - 72  are arranged in upper and lower pairs, wherein the guideways  66 - 72  of each pair extend in opposite directions.  
     [0022] The second plow section  18  and the third plow section  22  are similar in construction and operation, therefore, a description of the second plow section  18  should be considered descriptive of both the second plow section  18  and the third plow section  22 . The second plow section  18  includes a plate  76  that includes the second plowing surface  20  and a rear surface  78 . The plate  76  is provided with a bend  80  located at a midpoint along the height thereof, thereby providing the second plowing surface  76  with a forwardly facing, concave cross-sectional configuration. The second plow section also  18  includes a pair of followers  82  and  84 , each provided with a square-shaped, cross-sectional configuration, constructed of steel, and slidably received within the guideways  68  and  70 , respectively. The second plow section  18  further includes a pair of webs  86  that extend through slots  74  of guideways  66  and  70  and are connected to the rear surface of  78  of plate  76  and the followers  82  and  84 , respectively. The second plow section  18  and the third plow section  22  are each provided with end plates  98  to prevent the accumulation of snow in front of plowing surfaces  14 ,  20  and  24  from moving around the ends of the extendable plow  10 . Angled reinforcement plates  100  are welded to the end plates  98  as well as respective plowing surfaces  20  and  24 , thereby structurally reinforcing the end plates  98 .  
     [0023] The extendable plow  10  further includes a pair of coaxial hydraulic actuators  88  and  90  that are mounted between the guideway pairs, and thus provide for a balance of the resistant forces in the guideways  66 - 72  on the opposite sides of the thrust axis provided by the actuators  88  and  90 . The hydraulic actuators  88  and  90  and preferably attached at their opposite ends to tabs  92 . The ends of cylinders  88  and  90  are attached to tabs  92  via bolts extending therethrough, thereby allowing separation of the second plow section  18  and the third plow section  22  from the first plow section  12  when required.  
     [0024] In operation, the hydraulic actuators  88  and  90  are utilized to move the second and third plow sections  18  and  22 , respectively, between the retracted position and the extended position. The first, second and third plowing surfaces  14 ,  20  and  24 , respectively cooperate to form an uninterrupted total plowing surface when in the extended position. Further, the first, second and third width of the first, second, and third plowing surfaces  14 ,  20  and  24 , respectively, cooperate to form a total plowing width that is substantially double the first width of the first plowing surface  14 .  
     [0025] As best illustrated in FIG. 4, the lower portion of each of the plow sections  12 ,  18  and  22  are defined by elongated rubber blocks  94 . The blocks  94  are secured to the respective plow sections  12 ,  18  and  22  by nut, bolt and washer arrangements  96 . The arrangement of plow sections  12 ,  18  and  22  above a rough ground surface is thus given a more effective sweeping action, as well as considerably reducing the level of sound generated by the operation of extendable plow  10 .  
     [0026] The reference numeral  10   a  (FIG. 6) generally designates another embodiment of the present invention, having an alternative support assembly  102 . Since the extendable plow  10   a  is similar to the previously described extendable plow  10 , similar parts appearing in FIG. 5 and FIG. 6 respectively are represented by the same, corresponding reference numeral, except for the suffix “a” in the numerals of the latter. In the illustrated example, the extendable plow  10   a  includes a plurality of upper support bars  104  and a plurality of lower support bars  106  paired therewith and providing a gap  108  therebetween. Each of the upper support bars  104  and lower support bars  106  extend rearwardly from and are affixed to the rear surface  32   a  of the first plow section  12   a . A plurality of angled support beams  110  extend between the rear surface  32   a  and an upper surface of each of the upper support bars  104 , thereby providing structural reinforcement thereto. In operation, the tongue of a bucket of a loader (not shown) is placed within the gap  108  between the upper support bars  104  and the lower support bars  106 . A pair of chains  112  connected to a pair of hooks  114  attached to and extending rearwardly from rear surface  32   a  extend about the bucket, thereby securing the bucket to the extendable plow  10   a.    
     [0027] The reference numeral  10   b  (FIG. 7) generally designates another embodiment of the present invention, having an alternative support assembly  116 . Since the extendable plow  10   b  is similar to the previously described extendable plow  10 , similar parts appearing in FIG. 5 and FIG. 7 respectively are represented by the same, corresponding reference numeral, except for the suffix “b” in the numerals of the latter. In the illustrated, the support assembly  116  includes a pair of rearwardly extending downwardly opening hooks  118  affixed to and located near a top portion of rear surface  32 . The support assembly  116  further includes a pair of rearwardly extending tabs  120  located near a lower portion and attached to rear surface  32   b . Each tab  120  includes a horizontally extending aperture  122  extending therethrough. In operation, a lifting assembly (not shown) of a vehicle is connected with the support assembly  116  by inserting a support mechanism beneath hooks  118  and connected with tabs  120  by extending movable pins into apertures  122 . It should be noted that the tabs  120  and the associated apertures  122  may be provided at different orientations.  
     [0028] In the foregoing description, it will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed herein. Such modifications are to be considered as included in the following claims, unless these claims by their language expressly state otherwise.