The present invention relates generally to snow plows, and more particularly to snow plow assemblies having a floating A-frame.
Snow plow assemblies are used on commercial, residential, or all-purpose vehicles for the effective removal of snow from the ground. A typical snow plow assembly includes a mounting frame coupled to a moldboard assembly for plowing the snow, a push frame pivotably connected to the mounting frame for allowing lateral pivoting movement of the mounting frame and moldboard assembly, and a lift frame operatively coupled to the push frame for vertically raising or lowering the push frame and the mounting frame. During the use of such snow plow assemblies, the vehicle and/or snow plow assembly may travel over irregular or uneven ground surfaces, which may cause uneven removal of snow from the ground. In addition, the snow plow assembly may experience a significant amount of pushing and pulling force during normal use, which can cause a significant amount of stress and wear on the snow plow assembly.
The present invention provides a snow plow assembly having a push frame, a lift frame, and a coupling configured to floatably attach the push frame to a lift frame. The coupling may attach the left and right sides of the push frame to the corresponding left and right sides of the lift frame, and each coupling may be vertically floatable independently of one another to allow the push frame to float vertically relative to the lift frame, while also allowing the push frame to rotate about a longitudinal axis relative to the lift frame. Such vertical and/or rotational movement of the push frame relative to the lift frame enables the snow plow assembly to improve snow removal by accommodating for irregular or uneven ground surfaces when the snow plow assembly is in use.
At least one of the couplings may include a retaining member for operatively coupling the push frame to the lift frame, and one or more bearing blocks that facilitate distribution of load exerted on the push frame when in use. For example, the bearing block may be configured to have bearing surfaces that enhance the distribution of load between the push frame and the retaining member to reduce the concentration of stresses and wear on the push frame. The bearing block may be a sacrificial wear component that preferentially allows wear of the bearing block, while minimizing wear on the more expensive push frame component, and provides for the wear block to be easily replaceable when significant wear has occurred. The bearing block also may be slidably movable against the push frame for common movement with the retaining member to allow the coupling to float vertically with respect to the push frame.
According to an aspect of the invention, a snow plow assembly for a vehicle includes: a push frame to which a moldboard is mountable for enabling removal of snow; a lift frame configured for mounting to the vehicle; a lift device mounted to the lift frame, the lift device configured to vertically raise or lower the push frame and the moldboard relative to a horizontal plane; and a first coupling and a second coupling, the first coupling attaching a left side of the push frame to a corresponding left side of the lift frame, and the second coupling attaching a right side of the push frame to a corresponding right side of the lift frame; wherein the respective first and second couplings are configured to allow each of the left and right sides of the push frame to float vertically relative to the respective left and right sides of the lift frame, and are configured to allow the left and right sides of the push frame to float vertically independently of one another, thereby allowing the push frame to rotate relative to the lift frame about a longitudinal axis extending in a forward direction, which enables the snow plow assembly to accommodate for irregular or uneven ground surfaces when the snow plow assembly is in use.
According to another aspect of the invention, a snow plow assembly for a vehicle includes: a push frame to which a moldboard is mountable for enabling removal of snow; a lift frame configured for mounting to the vehicle; a lift device mounted to the lift frame, the lift device configured to vertically raise or lower the push frame and the moldboard relative to a horizontal plane; and a coupling configured to couple the push frame to the lift frame, the coupling including a bearing block and a retaining member; wherein the retaining member is configured to operatively couple the push frame to the lift frame while permitting the push frame to float vertically relative to the lift frame, and wherein the bearing block is interposed between the retaining member and the push frame, the bearing block being configured to distribute at least some load exerted on the push frame to the retaining member, thereby reducing wear on the push frame when the snow plow assembly is in use.
According to another aspect of the invention, a snow plow assembly includes: a mounting bar having one or more mounting interfaces for coupling to a moldboard assembly; an A-frame having a forward vertex portion and left and right rearward portions laterally spaced apart in the transverse horizontal direction, the forward vertex portion having an interface for pivotably connecting a portion of the mounting bar for enabling lateral pivoting movement of the mounting bar relative to the A-frame; a lift frame having an upper portion that extends upright above the A-frame and the mounting bar, the upper portion having a forwardly extending lift arm connected to a lift device, the lift arm being operably connected to a portion of the A-frame, such that activation of the lift device vertically raises or lowers the A-frame and the mounting bar relative to a horizontal plane; and a first coupling and a second coupling, the first coupling attaching the left rearward portion of the A-frame to a corresponding left portion of the lift frame, and the second coupling attaching a right rearward portion of the A-frame to a corresponding right portion of the lift frame; wherein each of the first coupling and the second coupling include a bearing block and a retaining member, the respective bearing blocks and retaining members being configured to move vertically relative to the corresponding left and right rearward portions of the push frame to allow each of the left and right rearward portions of the push frame to float vertically relative to the corresponding left and right portions of the lift frame, and are configured to allow the left and right rearward portions of the push frame to float vertically independently of one another, thereby allowing the push frame to rotate relative to the lift frame about a longitudinal axis extending in a forward direction to accommodate for irregular or uneven ground surfaces when the snow plow assembly is in use; and wherein for each of the first coupling and the second coupling, the bearing block is interposed between the retaining member and the corresponding left or right rearward portion of the push frame, the respective bearing blocks being configured to distribute at least some load exerted on the push frame to the respective retaining members, thereby reducing wear on the push frame when the snow plow assembly is in use.
The following description and the annexed drawings set forth certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features according to aspects of the invention will become apparent from the following detailed description when considered in conjunction with the drawings.
The annexed drawings, which are not necessarily to scale, show various aspects of the invention.
The principles of the present invention have particular application to snow plow assemblies for a vehicle, including commercial, residential, or all-purpose vehicles, and will be described below chiefly in this context. It is also understood, however, that the principles of the present invention may be applicable to other plow assemblies or vehicle-mounted accessories for other applications where it is desirable to provide one or more couplings that allow a push frame to be floatably coupled to a lift frame for accommodating irregular or uneven ground surfaces; and/or where it is desirable to provide one or more bearing blocks in the coupling to improve the load distribution on the push frame to reduce wear.
In the discussion above and to follow, the terms “upper”, “lower”, “top”, “bottom,” “inner,” “outer,” “left,” “right,” “above,” “below,” “horizontal,” “vertical,” etc. refer to the snow plow assembly as viewed in a horizontal position, as shown in
Referring to
In the illustrated embodiment, the snow plow assembly 10 includes a mounting bar 22 having one or more mounting interfaces 24, such as suitable brackets or the like, for operatively mounting the moldboard 14 to the push frame 12. As shown, the mounting bar 22 is pivotably connected to the push frame 12 via a suitable connection 26, such as via one or more brackets and bolts, for enabling lateral pivoting movement (e.g., left/right pivoting movement) of the mounting bar 22 relative to the push frame 12 about a vertical pivot axis 28. One or more pivot devices 30 may be connected to the left and/or right sides of the mounting bar 22, and connected to the left and/or right sides of the push frame 12, to enable the pivoting movement of the mounting bar 22 about the pivot axis 28. In the illustrated embodiment, the pivot devices 30 are fluid-operated piston-cylinder devices that may extend and retract to provide such pivoting movement to the mounting bar 22.
The moldboard 14 (shown diagrammatically in
In the illustrated embodiment, the push frame 12 is configured as an A-frame having rear crossbar 34 and a pair of side bars 36 arranged in a triangular or “A” configuration. The side bars 36 converge in the forward direction to form a vertex portion of the push frame, which may include the interface 26 for pivotably mounting the mounting bar 22. The rear crossbar 34 extends in a transverse direction and is operatively connected to the side bars 36 via any suitable means, such as welding or fastening. The push frame 12 also includes a pair of rearwardly projecting left and right ears 38 (also referred to as rearward projections) that are connected to the lateral sides of the rear cross bar 34. It is understood that although the push frame 12 is shown as being a multiple component construction, one or more of the components of the push frame 12 shown in the illustrated embodiment may be integral and unitary with each other.
The lift frame 16 is generally vertically oriented and includes an upper portion 40 that extends upright above the push frame 12, and a lower portion 42 that is coupled to the push frame 12. The lower portion 42 also is operatively coupled to the vehicle 18. In the illustrated embodiment, the lower portion 42 of the lift frame 16 includes mounting hooks 44 for removably mounting the lift frame 16 to a mount frame 46 (shown diagrammatically in
The lift frame 16 includes a pair of vertical support members 50 that are transversely spaced apart frame one another. One or more transverse crossmembers 52, 54 may connect the vertical cross members 50 at the upper portion 40 of the lift frame 16. As shown, a lift device 56 is mounted to the lift frame 16 and is also operatively coupled to the push frame 12 such that activation of the lift device 56 vertically raises or lowers the push frame 12 and the moldboard 14 relative to a horizontal plane 58. In the illustrated embodiment, a forwardly extending lift arm 60 is operably coupled to one of the crossmembers 54, and a tether 62, such as a chain or other suitable linkage, operably connects the lift arm 16 to the push frame 12. The lift device 56 is coupled to the cross member 52 on one end of the lift device, and is connected to the lift arm 60 at the opposite end of the lift device 56. In the illustrated embodiment, the lift device 56 is a fluid operated piston-cylinder device in which extension or retraction of the device causes the lift arm 60 to pivot upwards or downwards relative to the crossmember 54 and the vertical support members 50, thereby causing the forward portion of the push frame 12 to raise or lower via the chain 62.
As shown, the lift frame 16 also may include a housing 64 that spans the space between the vertical support members 50. The housing 64 may contain electronic and/or fluid (e.g., hydraulic) devices and may act as a shield to the snow. As shown, one or more electrical conduits 66 and/or one or more fluid conduits 68 may extend from the housing 64 to provide a source of power to one or more of the pivot devices 30, lift device 56, and/or lights 70 (shown in
The lower portion of the lift frame 42 may include another crossmember 74 extending between the laterally spaced apart supports 50. One or more spring-loaded pins 76 may be operatively connected to the crossmember 74 and the supports 50 to facilitate transverse side-to-side movement of the lift frame 16 when the snow plow assembly is in use. As shown, the lift frame 16 may include inner lift frame members 78 and outer lift frame portions 80 that together form a clevis through which the spring-loaded pins 76 extend. The inner lift frame members 78 may be configured to engage the respective springs of the spring-loaded pins 76 to facilitate the lateral side-to-side movement. The inner lift frame members 78 and the outer lift frame portions 80 may each have the hooks 44 for removably mounting the lift frame 16 to the mounting frame 46, as discussed above. In addition, the inner lift frame members 78 and the outer lift frame portions 80 may cooperate with each other to couple the lift frame 16 to the push frame 12 via the couplings 20, as discussed in further detail below. It is understood that although the lift frame 16 is shown as being a multiple component construction, one or more of the components of the lift frame 16 shown in the illustrated embodiment may be integral and unitary with each other as may be desired.
Referring particularly to
In the illustrated embodiment, the couplings 20 each include a retaining member 84 for operatively coupling the push frame 12 to the lift frame 16. As shown, the rearwardly extending portion 38 of the push frame 12 includes a vertically elongated slot 86 defined by inner surfaces 88 of the push frame 12. The vertical slot 86 is configured to receive the retaining member 84 and allows the retaining member 84 to move vertically up and down within the vertical slot 86 to permit the respective left and right sides of the push frame 12 to float vertically, and independently, relative to the corresponding left and right sides of the lift frame 16. In the illustrated embodiment, the upper and lower portions of the inner surfaces 88 of the vertical slot 86 may act as vertical stops that restrict the vertical floating movement of the retaining member 84.
As shown, the couplings 20 also may include at least one bearing block 90 at least partially interposed between the retaining member 84 and the push frame 12 in the forward and/or rearward longitudinal directions. In the illustrated embodiment, the bearing block 90 has a through-hole 92 defined by inner surfaces 94 configured to receive the retaining member 84 in the transverse direction. In this manner, the retaining member 84 may extend through the through-hole 92 in the bearing block 90 and extends into the vertically elongated slot 86 of the push frame 12. Generally, the retaining member 84 may have a relatively tight fit with the inner surfaces 94 defining the through-hole 92 of the bearing block 90, and may have a relatively loose fit with the inner surfaces 88 defining the vertical slot 86 of the push frame 12. This may allow the retaining member 84 to preferentially engage and exert force against the inner surfaces 94 of the bearing block 90 when pushing or pulling loads are exerted on the snow plow assembly 10, while restricting or limiting the engagement of the retaining member 94 against the inner surfaces 88 of the push frame 12, which may reduce wear on the inner surfaces 88 of the vertical slot 86.
The bearing block(s) 90 also may be configured to enhance distribution of loads between the push frame 12 and the retaining member 84 by distributing the pushing and pulling loads exerted on the push frame 12 over a greater area for reducing wear on the push frame 12. For example, in the illustrated embodiment, the push frame 12 includes longitudinally spaced apart stops 96 between which the bearing block 90 is disposed for engagement with the stops 96 when the pushing and pulling loads are exerted on the push frame 12. In this manner, the forces exerted on the push frame 12 are transferred to the bearing block(s) 90 through the stops, and are then transferred through the bearing block(s) 90 to the retaining member 84 and then to lift frame 16 which is operably supported by the vehicle 18.
To reduce the concentration of forces on portions of the push frame 12, the bearing surfaces 98 of the stops 96 which contact the bearing surfaces 100 of the bearing block(s) 90 may have a contact area that is greater than the area of contact between the bearing block(s) 90 and the retaining member 94. The bearing block 90 also may have a tighter fit between the stops 96 (e.g., less longitudinal spacing or slack) than the retaining member 84 has within the vertical slot 86 of the push frame, such that as the load is exerted on the push frame 12, the limited slack between the push frame stops 96 and the bearing block(s) 90 preferentially allows the load to be transmitted through the bearing block(s) 90, rather than allowing the retaining member 84 to engage the inner surfaces 88 of the vertical slot 86. Because the bearing block(s) 90 may be configured to take a higher concentration of the load in those locations where the bearing block 90 engages the retaining member 84 (e.g., at the inner surfaces 94 of the through-hole 92), the bearing block 90 may have an increased amount of wear compared to the engagement portions of the push frame 12 (e.g., the stops 96). The bearing block 90, however, may be a relatively inexpensive and easy to replace component compared to the push frame 12, and thus the bearing block 90 may be considered a sacrificial and replaceable wear block. In some embodiments, the stops 96 of the push frame also may be removably mountable to allow for replacement of the stops 96, however, it is also understood that the stops 96 may be fixedly attached to the rearward projections of the push frame 38, such as via welding or other suitable attachment.
The bearing block(s) 90 also may be configured to enable the vertical floating movement of the push frame 12 relative to the lift frame 16. For example, in the illustrated embodiment, each of the longitudinally spaced apart stops 96 extend in the vertical direction to form a vertical guide slot within which the bearing block 90 is slidably disposed. In this manner, the bearing blocks 90 may be configured to engage the stops 96 while sliding vertically within the vertical guide slot as the retaining member 84 moves vertically within the vertically elongated slot 86 of the push frame 12. In the illustrated embodiment, the forward and rearward bearing surfaces 100 of the bearing block 90 are vertically oriented such that the bearing surfaces 100 of the bearing block 90 and the bearing surfaces 98 of the vertically elongated stops 96 are all parallel to each other in the vertical direction. Such a configuration of the bearing block 90 also increases the effective contact area with the stops 96 to reduce force concentrations as discussed above. In the illustrated embodiment, the bearing block 90 is a relatively easy to manufacture component having a generally parallelepiped or rounded-square shape, in which its thickness in the transverse direction is less than a width of at least one of its sides.
As shown, each of the couplings 20a and 20b attaching the left and right sides of the push frame 12 to the lift frame 16 may have more than one bearing block 90 disposed between a set of stops 96 of the push frame, which may further increase the contact area between the bearing blocks 90 and the push frame 12 to further reduce the concentration of forces and wear on the push frame 12. In the illustrated embodiment, each coupling 20a and 20b has two bearing blocks 90 and 91 slidably disposed between vertical stops 96 and 97 on opposite inner and outer sides of the rearward projection 38 of the push frame 12. In such a configuration, the vertically elongated slot 86 of the push frame 12 may be configured as a through-slot that extends in the transverse direction through the rearward projection 38 of the push frame 12, such that the retaining member 84 may extend through the through-hole 92 in the outer bearing block 90, through the vertically elongated through-slot 86 interposed between the bearing blocks 90 and 91, and then through the through hole 93 in the inner bearing block 91. In this manner, each of the outer and inner bearing blocks 90, 91 may be configured to transmit and distribute load between different portions of the push frame (e.g., the inner and outer stops 96, 97) and different portions of the retaining member 94. In addition, each of the outer and inner bearing blocks 90, 91 may be configured to vertically slide within the vertically elongated inner and outer guide slots formed between the respective stops 96, 97 to enable the floating movement of the respective couplings 20a and 20b, as discussed above.
In the illustrated embodiment, the retaining member 84 is configured to protrude outwardly of the outer bearing block 90 and is configured to protrude inwardly of inner bearing block 91 to allow for connection to respective inner and/or outer portions of the lift frame 16. In the illustrated embodiment, the lift frame 16 forms a clevis with the inner lift frame member 78 (inner portion) and the outer lift frame portion 80, and each of the inner and outer portions of the lift frame have a through-hole 102, 103 through which the retaining member 84 extends for operatively coupling the push frame 12 to the lift frame 16. In the illustrated embodiment, the retaining member 84 is configured as a cylindrical pin having a head 104 on one end and a catch 106, such as a cotter pin, on the opposite end. The head 104 may be sized greater than the size of the through hole 102 in the lift frame outer portion to restrict too much inward lateral movement of the retaining member 84, and the catch 106, which may cooperate with a washer 108, may be configured to engage the inner portion 78 of the lift frame to restrict too much outward lateral movement of the retaining member 84. The retaining member 84 is preferably configured with a sufficient size and made of a suitable material to withstand the loads exerted on the pin without significant plastic deformation when the snow plow assembly is in use.
It is understood that although a preferred configuration of the exemplary snow plow assembly 10 including the floating coupling(s) 20 has been described and shown, it would be apparent to those having ordinary skill in the art that other push frame 12 and/or lift frame 16 designs could also be used with the present invention. The invention is not limited to any particular snow plow assembly design, but rather is appropriate for a wide variety of commercially-available snow plow assemblies. Furthermore, although the principles and aspects of the present invention have particular application to snow plow assemblies, it is understood that such principles and aspects may be applicable to other plow assemblies in general, or to other vehicle mounted or machine accessories upon which forces are exerted and which may be desirable to provide one or more floatable couplings that allow independent movement relative to each other and/or cooperate to provide rotational movement, and/or where it is desirable to provide one or more bearing blocks in the coupling to improve the load distribution, such as for vehicle-mounted rotating brushes, or the like.
It is furthermore understood that although a preferred exemplary embodiment of the coupling 20 has been shown and described, other suitable alternatives are possible. For example, although the retaining member 84 and bearing block(s) 90 are shown as being vertically movable relative to the push frame 12 and fixed in position relative to the lift frame 16, these features could instead be reversed to allow the retaining member 84 and/or bearing block(s) 90 to be vertically movable relative to the lift frame 16 while being fixed in position relative to the push frame 12. In such a situation, the lift frame 12 may have the vertically elongated slot 86 and/or the one or more vertical guide slots formed by the stops 96, 97 as described above.
It is furthermore understood that although the retaining member 84 is shown as extending all the way through the vertical slot 86 (configured as a through-slot) in the push frame 12, the vertical slot 86 could instead be configured as a vertical groove within which an end of the retaining member 84 could move without projecting therethrough. Furthermore, in some embodiments, the coupling 20 may include the retaining member 84 slidably engaging the inner surfaces 88 of the vertical groove 86 to provide the floating and rotation features discussed above without the bearing block(s) 90, 91. The bearing block 90 is beneficial, however, in distributing the load as discussed above, and it is noted that the ability of the retaining member 84 to extend through the vertical through-slot 86 facilitates the use of multiple bearing blocks 90, 91 to further enhance load distribution.
It is also understood that the push frame 12 could be devoid of the vertical slot 86, in which case the coupling 20 could be configured with the retaining member 84 disposed in the bearing block 90 and the bearing block 90 configured to be slidable within the vertical guide slot formed by the stops 96 to provide the vertical floating features discussed above. Alternatively, it is also understood that the bearing block(s) 90, 91 could be provided without being slidable for enhancing the wear performance as discussed above without the floatable features.
As used herein, an “operable connection,” or a connection by which entities are “operably connected,” is one in which the entities are connected in such a way that the entities may perform as intended. An operable connection may be a direct connection or an indirect connection in which an intermediate entity or entities cooperate or otherwise are part of the connection or are in between the operably connected entities.
Although the invention has been shown and described with respect to a certain embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described elements (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.
Number | Name | Date | Kind |
---|---|---|---|
1920475 | Meyer | Aug 1933 | A |
1964617 | Bird | Jun 1934 | A |
4281847 | Robe | Aug 1981 | A |
4342163 | Hoekstra | Aug 1982 | A |
4596081 | DeBilly | Jun 1986 | A |
5148617 | Feller | Sep 1992 | A |
5638618 | Niemela | Jun 1997 | A |
5950336 | Liebl | Sep 1999 | A |
6154986 | Hadler | Dec 2000 | A |
6170178 | Christy | Jan 2001 | B1 |
6178669 | Quenzi | Jan 2001 | B1 |
6393737 | Quenzi | May 2002 | B2 |
6928757 | Bloxdorf et al. | Aug 2005 | B2 |
7089692 | Strait | Aug 2006 | B2 |
7491027 | McFarland | Feb 2009 | B1 |
7562718 | Moorman | Jul 2009 | B1 |
7588092 | Liebl | Sep 2009 | B2 |
7805862 | Osgood | Oct 2010 | B2 |
7805866 | Osgood | Oct 2010 | B1 |
8850724 | Bloxdorf | Oct 2014 | B2 |
10119233 | Holman | Nov 2018 | B2 |
20070271828 | Mishra | Nov 2007 | A1 |
20080053673 | Dilworth | Mar 2008 | A1 |
Number | Date | Country | |
---|---|---|---|
20190257047 A1 | Aug 2019 | US |