METHOD AND APPARATUS FOR MAINTAINING LEVEL PLOW WHEN ANGLING

Abstract

A support assembly that includes first and second frame components may be used to support a plow blade to a vehicle. The first frame component may have a first end defining a first pivot axis about which the plow blade pivots when it is moved side-to-side. The second frame component may have a first end that defines a second pivot axis about which the second frame component, the first frame component and the plow blade pivot when the plow blade is raised or lowered. A second end of the first frame component may be pivotally attached to a second end of the second frame component about a third pivot axis. The first frame component and the plow blade may automatically pivot together about the third pivot axis to maintain the plow blade in a level orientation even when the plow blade is both raised and moved side-to-side.

Description

This application claims priority to U.S. Ser. No. 61/614,594, entitled METHOD AND APPARATUS FOR MAINTAINING LEVEL PLOW WHEN ANGLING, filed Mar. 23, 2012, which is incorporated herein by reference.

I. BACKGROUND OF THE INVENTION

This invention pertains to the art of methods and apparatuses for plow assemblies and more specifically to methods and apparatuses for supporting a plow blade to a vehicle so that it is maintained in a level orientation even when the plow blade is both raised and moved side-to-side.

II. SUMMARY OF THE INVENTION

According to one embodiment of this invention, a plow assembly may comprise a plow blade assembly comprising: a plow blade having a plow surface that is suitable to contact and plow an associated plowable substance; and, a support assembly that supports the plow blade assembly to an associated vehicle. The support assembly may comprise: (1) a blade support structure that is attached to the plow blade assembly and that supports the plow blade assembly to the support assembly; (2) a blade height adjustment mechanism that is operable to raise and lower the blade support structure and the plow blade assembly with respect to an associated ground surface; and, (3) a blade side-to-side adjustment mechanism comprising: (a) a first frame component comprising: a first end attached to the blade support structure and defining a substantially vertical first pivot axis about which the blade support structure and the plow blade assembly are pivotal together with respect to the first frame component; and a second end; (b) a second frame component comprising: a first end defining a second substantially horizontal pivot axis about which the second frame component is pivotal with respect to the vehicle when the blade height adjustment mechanism operates to raise and lower the blade support structure and the plow blade assembly; and a second end; (c) at least a first power device that is operable to cause the blade support structure and the plow blade assembly to pivot together about the first pivot axis; and, (d) wherein the second end of the first frame component is pivotally attached to the second end of the second frame component about a substantially horizontal third pivot axis so that the first frame component, the blade support structure and the plow blade assembly are automatically pivotal together about the third pivot axis to maintain the plow blade in a level orientation when: (i) the blade height adjustment mechanism is operated to raise the blade support structure and the plow blade assembly with respect to the associated ground surface; and, (ii) the first power device is operated to cause the blade support structure and the plow blade assembly to pivot together about the first pivot axis.

According to another embodiment of this invention, a plow assembly may comprise a plow blade assembly comprising: a plow blade having a plow surface that is suitable to contact and plow an associated plowable substance; and, a support assembly that supports the plow blade assembly to an associated vehicle. The support assembly may comprise: (1) a blade support structure that is attached to the plow blade assembly and that supports the plow blade assembly to the support assembly; (2) a blade height adjustment mechanism that is operable to raise and lower the blade support structure and the plow blade assembly with respect to an associated ground surface; and, (3) a blade side-to-side adjustment mechanism comprising: (a) a first frame component comprising: a first end attached to the blade support structure and defining a first pivot axis about which the blade support structure and the plow blade assembly are pivotal together with respect to the first frame component; and a second end; (b) a second frame component comprising: a first end defining a second pivot axis about which the second frame component is pivotal with respect to the vehicle when the blade height adjustment mechanism operates to raise and lower the blade support structure and the plow blade assembly; and a second end; (c) at least a first power device that is operable to cause the blade support structure and the plow blade assembly to pivot together about the first pivot axis; and, (d) wherein the second end of the first frame component is pivotally attached to the second end of the second frame component about a third pivot axis so that the first frame component, the blade support structure and the plow blade assembly are pivotal together about the third pivot axis.

According to one embodiment of this invention, a method of maintaining a plow blade in a level orientation may comprise the steps of: (A) providing a plow assembly comprising: (I) a plow blade assembly comprising: a plow blade having a plow surface that is suitable to contact and plow an associated plowable substance; and, (II) a support assembly that supports the plow blade assembly to an associated vehicle, the support assembly comprising: (1) a blade support structure that is attached to the plow blade assembly and that supports the plow blade assembly to the support assembly; (2) a blade height adjustment mechanism; (3) a blade side-to-side adjustment mechanism comprising: (a) a first frame component comprising: a first end attached to the blade support structure and defining a first pivot axis; and a second end; (b) a second frame component comprising: a first end defining a second pivot axis; and a second end; (c) at least a first power device; and, (d) wherein the second end of the first frame component is pivotally attached to the second end of the second frame component about a third pivot axis; (B) operating the blade height adjustment mechanism to pivot the second frame component about the second pivot axis and to raise the blade support structure and the plow blade assembly with respect to an associated ground surface; (C) operating the first power device to cause the blade support structure and the plow blade assembly to pivot together about the first pivot axis with respect to the first frame component; and, (D) maintaining the plow blade in a level orientation by automatically pivoting the first frame component, the blade support structure and the plow blade assembly together about the third pivot axis with respect to the second frame component.

III. BRIEF DESCRIPTION OF THE DRAWINGS

The invention may take physical form in certain parts and arrangement of parts, embodiments of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof and wherein:

FIG. 1 is a perspective front view of a vehicle equipped with a plow assembly.

FIG. 2 is a side perspective close-up view of the vehicle and plow assembly shown in FIG. 1.

FIG. 3 is a top perspective close-up view of the plow assembly shown in FIG. 1.

FIG. 4 is a perspective side close-up view of the plow assembly shown in FIG. 1.

FIG. 5 is a side perspective schematic view of the lift mechanism shown in FIG. 1 with the chain represented as a pair of rods.

FIG. 6 is a top perspective view of a support frame.

FIG. 7 is a bottom perspective view of the first frame component.

FIG. 8 is a top perspective view of the first frame component.

FIG. 9 is a view taken along the line 9-9 of FIG. 8.

FIG. 10 is a view taken along the line 10-10 of FIG. 8.

FIG. 11 is a top perspective view of the second frame component.

FIG. 12 is a view taken along the line 12-12 of FIGURE

FIG. 13 is an end view of the second frame component of FIG. 11.

FIG. 14 is a perspective view of a clevis.

FIG. 15 is a top view of the clevis of FIG. 16.

FIG. 16 is a side view of the clevis of FIG. 16.

FIG. 17 is a perspective end view of a support frame according to another embodiment.

FIG. 18 is a side perspective view of the support frame shown in FIG. 17.

FIG. 19 is an end view of the support frame shown in FIG. 17.

FIG. 20 is a view similar to that shown in FIG. 17 but it shows the first frame component rotated relative to the second frame component.

FIG. 21 shows a support frame according to yet another embodiment.

IV. DETAILED DESCRIPTION

Referring now to the drawings wherein the showings are for purposes of illustrating embodiments of the invention only and not for purposes of limiting the same, and wherein like reference numerals are understood to refer to like components, FIG. 1 shows a vehicle 10 equipped with a plow assembly 30 according to one embodiment of this invention. While the vehicle shown is commonly known as a pick-up truck, it should be understood that the plow assembly 30 of this invention will work well with any vehicle chosen with the sound judgment of a person of skill in the art. The plow assembly 30 may include a plow blade assembly 32 and a support assembly 34 that supports the plow blade assembly 32 to the vehicle 10. The plow blade assembly 32 has a plow blade 36 with a plow surface 38 that is suitable to be used to contact and plow snow, ice or the like as is well known to those of skill in the art. However, it should be understood that the plow assembly of this invention can be used with plow blades that are suitable to be used to contact and plow any plowable substance, such soil, chosen with the sound judgment of a person of skill in the art. While the plow blade 36 shown is of a specific type and shape, it should be understood that any plow blade chosen with the sound judgment of a person of skill in the art will work well with this invention.

With reference now to FIGS. 1, 2 and 5, the support assembly 34 may include a blade support structure 40, a blade height adjustment mechanism 42, and a blade side-to-side adjustment mechanism 44. The blade support structure 40 may have a distal (away from the vehicle) side to which the plow blade assembly 32 attaches. One or more tabs 46 may extend from the distal side and receive pins 48 that hold the plow blade assembly 32 to the support assembly 34. For the embodiment shown, the pins 48 also define a pivot axis A5 about which the plow blade assembly 32 can pivot or “trip” as is well known to those of skill in the art.

With reference now to FIGS. 1-5, the blade height adjustment mechanism 42 may include a lift frame 50 having a proximal (near the vehicle) end with one or more attachment brackets 52 which attach to the vehicle in a known manner. A lift arm 54 may have a proximal end pivotally attached, about generally horizontal and perpendicular to the length of the plow assembly 30 pivot axis Al, to the distal end of the lift frame 50. The lift arm 54 may extend distally from the distal end of the lift frame 50, as shown. A middle portion of a chain 56 may attach to the distal end of the lift arm 54 (such as via openings 58) and the opposite ends of the chain 56 may extend downwardly and attach to the blade support structure 40, as shown. Alternatively, two separate chains could be used. A power device or ram 60. such as hydraulic cylinder, may be connected between the lift frame 50 and the lift arm 54. as shown. In other embodiments, the power device may comprise a pneumatic cylinder or an electric motor. When the power device 60 is extended, the lift arm 54 pivots in direction D1 and exerts a lift force (tension) onto the chain 56 which cause the blade support structure 40 (and the plow blade assembly 32) to be lifted. When the power device 60 is contracted, the lift arm 54 pivots in the opposite direction which permits the blade support structure 40 (and the plow blade assembly 32) to be lowered. As the operation of a power device with a plow blade is well known to those of skill in the art, further details will not be provided here.

With reference now to FIGS. 2, 5 and 6, the blade side-to-side adjustment mechanism 44 may include a support frame 64 having a proximal end that pivots with respect to the vehicle 10. For the embodiment shown, the support frame 64 includes one or more attachment brackets 66 which pivotally attach, about a generally horizontal and perpendicular to the length of the plow assembly 30 pivot axis A2, to the lift frame 50, as shown. Alternatively, the proximal end of the support frame 64 could be pivotally attached to the vehicle. The distal end of the support frame 64 may have one or more attachment brackets 70 with pivotally attach, about a generally vertical axis A3, to the blade support structure 40. This permits the blade support structure 40 (and thus the plow blade assembly 32) to be pivoted about axis A3 from side to side. The blade support structure 40 may have one or more (two shown) contact surface 68 that contact the support frame 64 to limit the degree of pivoting about axis A3.

With reference now to FIGS. 2 and 5-10, the support frame 64 may be an A-frame (a frame shaped like the letter A), as shown. Unlike known support frames, however, support frame 64 is made of two primary frame components that are moveable relative to each other. Specifically, the support frame 64 shown has a first frame component 72 positioned relatively distally and a second frame component 74 positioned relatively proximally. The first frame component 72 includes the attachment brackets 70, 70 (two shown) which may have bushings 76 with openings 78 that receive a pivot pin 80 that is received in at least one opening in the blade support structure 40 and that defines the generally vertical pivot axis A3. The attachment brackets 70, 70 may “sandwich” the top and bottom surfaces of the blade support structure 40. The first frame component 72 may include a pair of tubes 82, 82 that form a V-shape with the distal ends attached to the attachment brackets 70, 70, as shown. A plate 84 may be attached to the proximal end of the first frame component 72. The plate 84 may have a pair of tabs 86, 86 extending from opposite sides of the first frame component 72, as shown. To provide further support and stability, atop and bottom plate 88, 90 may attached to the first frame component 72.

With reference now to FIGS. 2, 5-6 and 10-13, the second frame component 74 includes the attachment brackets 66, 66 which may extend proximally from an angle member 94 and which may have openings 92, 92 that receive pivot pins defining the pivot axis A2. A pair of tubes 96, 96 may form a V-shape and have proximal ends attached to the angle member 94. The distal ends of the tubes 96, 96 may be attached to a plate 98. Onto each side of the plate 98 at least one contact surface 101 may be provided. For the embodiment shown, each side of the plate 98 has a bracket 100 fixed thereto with an opening 102. Surfaces of the bracket 100 defining the opening 102 define two contact surfaces 101, 101 on the top and bottom of the opening 102, as indicated in FIG. 12. The plate 98 and brackets 100, 100 may be sized such that the plate 84 is positioned juxtaposed to the plate 98 and the tabs 86, 86 are received within the openings 102, 102. The height of each opening 102 may be greater than the height of each tab 86 so that relative motion is possible. In one embodiment, shown in FIGS. 11-12, the brackets 100 have an even thickness around the openings 102. In another embodiment, seen best in FIG. 18, one side 101A of the bracket 101 has a curved outer surface to provide additional strength.

With continuing reference to FIGS. 2, 5-6 and 10-13, the plate 98 may have a hole 104 and the plate 84 may have a hole 106. The holes 104, 106 may be positioned concentrically and receive a pivot pin 108 (most visible in FIG. 18) that defines a generally horizontal and parallel to the length of the plow assembly 30 pivot axis A4. In this way, the first frame component 72 is relatively pivotal with respect to the second frame component 74 about pivot axis A4. The top and bottom surfaces of the tabs 86 contact the contact surfaces to limit the relative pivotal motion in both rotational directions. The design shown is capable of providing about 12 degrees of relative pivoting of the first frame component 72 with respect to the second frame component 74. Other relative degrees of relative pivoting are easily attainable, as known by those of skill in the art. In an alternate embodiment, one or more contact surfaces 101 are provided on the first frame component 72 and one or more tabs are provided on the second frame component 74.

With reference now to FIGS. 2, 4-6, and 14-16 at least one power device or ram 110 (two shown), such as a hydraulic cylinder, may be connected between the second frame component 74 and the blade support structure 40. In other embodiments, the power device may comprise a pneumatic cylinder, an electric motor, or a biasing member such as a spring. For the embodiment shown, the proximal ends of the power devices 110, 110 are attached to a pair of attachment brackets 112, 112 on opposite sides of the second frame component 74 and the distal ends of the power devices 110, 110 are attached to a pair of attachment brackets 114 on the blade support structure 40. A clevis 116 may be used for each of these four attachments thus providing each end of each cylinder 110 with the capability of pivoting relatively both about a generally horizontal and perpendicular to the length of the plow assembly 30 pivot axis and about a generally vertical pivot axis.

With reference now to all the FIGURES, one advantage of this invention is realized when mounting and dismounting. It is well known for the ground surface upon which the plow assembly 30 is stored to be uneven. As a result, the elevation of the wheels on the vehicle (to which the plow assembly 30 is to be mounted) may be different that the elevation of the plow assembly 30. The relative motion permitted between the first frame component 72 and the second frame component 74, which occurs automatically, minimizes this problem.

Another advantage of this invention is realized when the plow blade assembly 32 is raised/lifted. The relative motion permitted between the first frame component 72 and the second frame component 74 allow the plow blade assembly 32 to remain substantially flat or level (at the same elevation) when it is raised/lifted (off the ground) and pivoted from side to side. Prior to this invention, lifting and side-to-side pivoting of known plow blade assemblies causes one end of the plow blade assembly to dip or drop in elevation. This creates a greater likelihood of inadvertently striking an object (including the ground) with the dipping edge of the plow blade. Suppose, for example, that the plow blade assembly 32 is in the position shown in FIG. 1, raised and angled generally straightforward. Suppose further that the operator then activates the controls to cause the plow blade assembly 32 to pivot to one side. Before this invention, such action by the operator would cause one end of the plow blade assembly 32 to dip. With this invention, however, such dipping does not occur. Instead, when the forces exerted on the blade support structure 40 by the chain 56 become uneven (this occurs when the side-to-side motion occurs) the first frame component 72 automatically pivots with respect to the second frame component 74 and the dipping is eliminated (or greatly minimized). Because of the use of the clevises 116, this relative motion of the first frame component 72 with respect to the second frame component 74 does no damage to the cylinders 110 as they easily accommodate to the corresponding differing elevations at the distal ends of the cylinders 110.

Yet another advantage of this invention is realized when the plow is used on an uneven surface. If the ground surface is angled to one side or undulates during plowing, the relative motion permitted between the first frame component 72 and the second frame component 74 allows the plow blade assembly 32 to automatically follow the ground surface contour.

FIGS. 17-20 show another embodiment. For this embodiment, the support frame 64 includes first and second frame components 72, 74 each having plates 84, 98, respectively, that are pivotal about pivot pin 108, as with previously described embodiments. However, this embodiment also includes an additional component(s) to maintain the plates 84, 98 in the proper relative position. Specifically, at least one bracket 130, two shown, “sandwich” the plates 84, 98 to maintain the proper relative position. The brackets 130, 130 may be positioned substantially equidistant from the longitudinal axis of the frame 64, as shown. In one embodiment, shown. the brackets 130 are fixed to the plate 98 but are movable with respect to the plate 84. This can be seen by comparing FIG. 17 to FIG. 20. In another embodiment, the brackets 130 are fixed to the plate 84 but are movable with respect to the plate 98. Each plate 84, 98 may have a tab 132, 134 respectively, extending from their upper surface, as shown. These tabs 132, 134 would contact the brackets 130, 130 if the side-to-side relative position of the plates 84, 98 was too great. In this way, the brackets 130, 130 and tabs 132, 134 together work as a “stop” to prevent undesirable relative motion.

FIG. 21 shows another embodiment where once again the support frame 64 includes first and second frame components 72, 74 each having plates 84, 98, respectively, that are pivotal about pivot pin 108. This embodiment uses a bracket 136 with an opening 138 that receives the tabs 132, 134 (similar to those shown in FIGS. 17-20) to prevent undesirable relative motion between the plates 84, 98 in a manner similar to the brackets 130, 130 discussed above.

Numerous embodiments have been described, hereinabove. It will be apparent to those skilled in the art that the above methods and apparatuses may incorporate changes and modifications without departing from the general scope of this invention. It is intended to include all such modifications and alterations in so far as they come within the scope of the appended claims or the equivalents thereof.

Having thus described the invention, it is now claimed:

Claims

1. A plow assembly comprising:

a plow blade assembly comprising: a plow blade having a plow surface that is suitable to contact and plow an associated plowable substance; and,

a support assembly that supports the plow blade assembly to an associated vehicle, the support assembly comprising:

(1) a blade support structure that is attached to the plow blade assembly and that supports the plow blade assembly to the support assembly;

(2) a blade height adjustment mechanism that is operable to raise and lower the blade support structure and the plow blade assembly with respect to an associated ground surface; and,

(3) a blade side-to-side adjustment mechanism comprising: (a) a first frame component comprising: a first end attached to the blade support structure and defining a substantially vertical first pivot axis about which the blade support structure and the plow blade assembly are pivotal together with respect to the first frame component; and a second end; (b) a second frame component comprising: a first end defining a second substantially horizontal pivot axis about which the second frame component is pivotal with respect to the vehicle when the blade height adjustment mechanism operates to raise and lower the blade support structure and the plow blade assembly; and a second end; (c) at least a first power device that is operable to cause the blade support structure and the plow blade assembly to pivot together about the first pivot axis; and, (d) wherein the second end of the first frame component is pivotally attached to the second end of the second frame component about a substantially horizontal third pivot axis so that the first frame component, the blade support structure and the plow blade assembly are automatically pivotal together about the third pivot axis to maintain the plow blade in a level orientation when: (i) the blade height adjustment mechanism is operated to raise the blade support structure and the plow blade assembly with respect to the associated ground surface; and. (ii) the first power device is operated to cause the blade support structure and the plow blade assembly to pivot together about the first pivot axis.

2. The plow assembly of claim 1 wherein:

the second end of the first frame comprises one of a first tab and a first contact surface;

the second end of the second frame comprises the other of the first tab and the first contact surface; and,

the first tab contacts the first contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis.

3. The plow assembly of claim 2 wherein:

the second end of the first frame comprises a first plate having a first hole and first and second ends;

the second end of the second frame comprises a second plate having a second hole and first and second ends;

the first plate is juxtaposed to the second plate with the first and second holes being substantially concentric and receiving a pivot pin that defines the third pivot axis;

a first bracket having a first opening is positioned on one of the first end of the first plate and the first end of the second plate, a first surface of the first bracket defining the first opening defines the first contact surface and a second surface of the first bracket defining the first opening defines a second contact surface;

the first tab is positioned on the other of the first end of the first plate and the first end of the second plate;

the first tab is received in the first opening;

the first tab contacts the first contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a first rotational direction; and,

the first tab contacts the second contact surface to limit the pivotal motion of the first frame component the blade support structure and the plow blade assembly about the third pivot axis in a second rotational direction that is opposite the first rotational direction.

4. The plow assembly of claim 3 wherein:

a second bracket having a second opening is positioned on one of the second end of the first plate and the second end of the second plate, a first surface of the second bracket defining the first opening defines a third contact surface and a second surface of the second bracket defining the first opening defines a fourth contact surface;

a second tab is positioned on the other of the second end of the first plate and the second end of the second plate;

the second tab is received in the second opening;

the second tab contacts the third contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in the first rotational direction; and,

the second tab contacts the fourth contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in the second rotational direction.

5. The plow assembly of claim 4 wherein the second pivot axis is substantially perpendicular to the third pivot axis.

6. The plow assembly of claim 5 wherein the first and second frame components together form an A-frame.

7. A plow assembly comprising:

a plow blade assembly comprising: a plow blade having a plow surface that is suitable to contact and plow an associated plowable substance; and,

a support assembly that supports the plow blade assembly to an associated vehicle, the support assembly comprising: (1) a blade support structure that is attached to the plow blade assembly and that supports the plow blade assembly to the support assembly; (2) a blade height adjustment mechanism that is operable to raise and lower the blade support structure and the plow blade assembly with respect to an associated ground surface; and, (3) a blade side-to-side adjustment mechanism comprising: (a) a first frame component comprising: a first end attached to the blade support structure and defining a first pivot axis about which the blade support structure and the plow blade assembly are pivotal together with respect to the first frame component; and a second end; (b) a second frame component comprising: a first end defining a second pivot axis about which the second frame component is pivotal with respect to the vehicle when the blade height adjustment mechanism operates to raise and lower the blade support structure and the plow blade assembly; and a second end; (c) at least a first power device that is operable to cause the blade support structure and the plow blade assembly to pivot together about the first pivot axis; and, (d) wherein the second end of the first frame component is pivotally attached to the second end of the second frame component about a third pivot axis so that the first frame component, the blade support structure and the plow blade assembly are pivotal together about the third pivot axis.

8. The plow assembly of claim 7 wherein:

the first pivot axis is substantially vertical with respect to the associated ground surface;

the second pivot axis is substantially horizontal with respect to the associated ground surface; and,

the third pivot axis is substantially horizontal with respect to the associated ground surface.

9. The plow assembly of claim 8 wherein the second pivot axis is substantially perpendicular to the third pivot axis.

10. The plow assembly of claim 7 wherein the first and second frame components together form an A-frame.

11. The plow assembly of claim 7 wherein:

the second end of the first frame comprises one of a first tab and a first contact surface;

the second end of the second frame comprises the other of the first tab and the first contact surface; and,

the first tab contacts the first contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis.

12. The plow assembly of claim 11 wherein:

the second end of the first frame comprises one of: first and second brackets defining the first contact surface and a second contact surface; and, the first tab and a second tab;

the second end of the second frame comprises the other of: the first and second brackets defining the first and second contact surfaces; and, the first and second tabs;

the first tab contacts the first contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a first rotational direction; and,

the second tab contacts the second contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a second rotational direction that is opposite the first rotational direction.

13. The plow assembly of claim 11 wherein:

the second end of the first frame comprises a first plate having first and second ends;

the first tab is positioned on the first end of the first plate;

the second end of the second frame comprises a second plate having first and second ends;

a first bracket having a first opening is positioned on the first end of the second plate;

a first surface of the first bracket defining the first opening defines the first contact surface and a second surface of the first bracket defining the first opening defines a second contact surface;

the first plate is juxtaposed to the second plate;

the first tab is received in the first opening;

the first tab contacts the first contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a first rotational direction; and,

the first tab contacts the second contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a second rotational direction that is opposite the first rotational direction.

14. The plow assembly of claim 11 wherein:

the second end of the first frame comprises a first plate having first and second ends;

the first tab is positioned on the first end of the first plate;

a second tab is positioned on the second end of the first plate;

the second end of the second frame comprises a second plate having first and second ends;

a first bracket having a first opening is positioned on the first end of the second plate;

a first surface of the first bracket defining the first opening defines the first contact surface;

a second bracket having a second opening is positioned on the second end of the second plate;

a second surface of the second bracket defining the second opening defines a second contact surface;

the first plate is juxtaposed to the second plate;

the first tab is received in the first opening;

the second tab is received in the second opening;

the first tab contacts the first contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a first rotational direction; and.

the second tab contacts the second contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a second rotational direction that is opposite the first rotational direction.

15. A method of maintaining a plow blade in a level orientation comprising the steps of:

(A) providing a plow assembly comprising: (I) a plow blade assembly comprising: a plow blade having a plow surface that is suitable to contact and plow an associated plowable substance; and, (II) a support assembly that supports the plow blade assembly to an associated vehicle, the support assembly comprising: (1) a blade support structure that is attached to the plow blade assembly and that supports the plow blade assembly to the support assembly; (2) a blade height adjustment mechanism; (3) a blade side-to-side adjustment mechanism comprising: (a) a first frame component comprising: a first end attached to the blade support structure and defining a first pivot axis; and a second end; (b) a second frame component comprising: a first end defining a second pivot axis; and a second end; (c) at least a first power device; and, (d) wherein the second end of the first frame component is pivotally attached to the second end of the second frame component about a third pivot axis;

(B) operating the blade height adjustment mechanism to pivot the second frame component about the second pivot axis and to raise the blade support structure and the plow blade assembly with respect to an associated ground surface;

(C) operating the first power device to cause the blade support structure and the plow blade assembly to pivot together about the first pivot axis with respect to the first frame component; and,

(D) maintaining the plow blade in a level orientation by automatically pivoting the first frame component, the blade support structure and the plow blade assembly together about the third pivot axis with respect to the second frame component.

16. The method of claim 15 wherein step (A) comprises the steps of:

providing the first pivot axis to be substantially vertical with respect to the associated ground surface;

providing the second pivot axis to be substantially horizontal with respect to the associated ground surface; and,

providing the third pivot axis to be substantially horizontal with respect to the associated ground surface and substantially perpendicular with respect to the second pivot axis.

17. The method of claim 15 wherein:

step (A) comprises the steps of: providing the second end of the first frame to comprise one of a first tab and a first contact surface; and, providing the second end of the second frame to comprise the other of the first tab and the first contact surface; and,

step (D) comprises the step of: limiting the pivoting of the first frame component, the blade support structure and the plow blade assembly together about the third pivot axis with respect to the second frame component by contacting the first tab with the first contact surface.

18. The method of claim 17 wherein:

step (A) comprises the steps of: (1) providing the second end of the first frame with one of: first and second brackets defining the first contact surface and a second contact surface; and, the first tab and a second tab; and, (2) providing the second end of the second frame with the other of: the first and second brackets defining the first and second contact surfaces; and, the first and second tabs; and,

step (D) comprises at least one of: (1) contacting the first tab to the first contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a first rotational direction; and, (2) contacting the second tab to the second contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a second rotational direction that is opposite the first rotational direction.

19. The method of claim 17 wherein:

step (A) comprises the steps of: (1) providing the second end of the first frame with a first plate having first and second ends; (2) providing the first tab to be positioned on the first end of the first plate; (3) providing the second end of the second frame with a second plate having first and second ends; (4) providing a first bracket having a first opening that defines the first contact surface and also defines a second contact surface on the first end of the second plate; (5) juxtaposing the first plate to the second p)ate; and, (6) positioning the first tab in the first opening; and,

step (D) comprises at least one of: (1) contacting the first tab to the first contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a first rotational direction; and, (2) contacting the first tab to the second contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a second rotational direction that is opposite the first rotational direction.

20. The method of claim 17 wherein:

step (A) comprises the steps of: (1) providing the second end of the first frame with a first plate having first and second ends; (2) providing the first tab on the first end of the first plate; (3) providing a second tab on the second end of the first plate; (3) providing the second end of the second frame with a second plate having first and second ends; (4) providing a first bracket having a first opening that defines the first contact surface on the first end of the second plate; (5) providing a second bracket having a second opening that defines a second contact surface on the second end of the second plate; (6) juxtaposing the first plate to the second plate; (7) positioning the first tab in the first opening; and, (8) positioning the second tab in the second opening; and,

step (D) comprises at least one of: (1) contacting the first tab to the first contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a first rotational direction; and, (2) contacting the second tab to the second contact surface to limit the pivotal motion of the first frame component, the blade support structure and the plow blade assembly about the third pivot axis in a second rotational direction that is opposite the first rotational direction.