BACKGROUND

[0001] The present invention relates to a ground clearance assembly for a snow blower to enable the snow blower to operate in a scraping mode and a non-scraping mode with respect to a ground surface over which the snow blower operates.

SUMMARY

[0002] In one embodiment, the invention provides a snow blower for clearing snow from a surface, the snow blower comprising: a prime mover; an auger housing having a leading edge and an opening over the leading edge to collect snow from the surface to be cleared into the auger housing; an auger system at least partially within the auger housing and operable under the influence of the prime mover to blow the snow that is collected into the auger housing in a desired direction; and a ground clearance assembly including a pivot arm having a proximal end that is pivotally mounted to the auger housing and a distal end, and a roller that is rotationally mounted to the distal end of the pivot arm; wherein the pivot arm is pivotable about a pivot axis between a first position in which the roller is pivoted out of engagement with the surface to be cleared such that the leading edge of the auger housing is positioned at least a first distance or a second distance from the surface while collecting the snow into the auger housing and a second position in which the roller is pivoted into engagement with the surface to be cleared to raise the leading edge above the surface to be cleared to not scrape against the surface to be cleared while collecting the snow into the auger housing.

[0003] In some embodiments, the first distance is zero to effect scraping of the leading edge against the surface. In some embodiments, the pivot axis is perpendicular to a direction of travel of the snow blower by the ground engaging element operating under the influence of the prime mover. In some embodiments, the pivot axis is parallel to the leading edge of the auger housing. In some embodiments, the pivot axis is a first height above the ground surface, the leading edge of the auger housing is a second height above the ground surface, and the first height is larger than the second height. In some embodiments, the snow blower further comprises a skid shoe mounted to the auger housing and sliding along the surface to be cleared to maintain a desired scraping action between the leading edge and the surface to be cleared when the pivot arm is in the first position. In some embodiments, the pivot arm lifts the skid shoe off the surface to be cleared when the pivot arm is in the second position.

[0004] In another embodiment, the invention provides a snow blower for clearing snow from a surface. The snow blower includes a prime mover, an auger housing, an auger system, a skid shoe, and a ground clearance assembly. The auger housing has a leading edge and an opening over the leading edge to collect snow from the surface into the auger housing. The auger system is at least partially within the auger housing and is operable under the influence of the prime mover to blow the snow that is collected into the auger housing in a desired direction. The skid shoe is mounted to the auger housing and has a lower surface that is engageable with the surface to be cleared in a first state of the auger housing. The ground clearance assembly is mounted to the auger housing and includes a roller. The roller is engageable with the surface to be cleared in a second state of the auger housing.

[0005] In some embodiments, the snow blower further includes a plate coupled to the auger housing. The skid shoe and the ground clearance assembly are mounted to the plate. The plate includes a portion that is cantilevered from the auger housing. In some embodiments, the ground clearance assembly includes a pivot arm that is mounted to the plate at a proximal end of the pivot arm, and the roller is mounted to the pivot arm at a distal end of the pivot arm. In some embodiments, the skid shoe includes a slot that receives a fastener to mount the skid shoe to the auger housing. In the first state of the auger housing, the skid shoe is adjustable with respect to the auger housing along the slot to adjust the position of the leading edge of the auger housing relative to the surface to be cleared. In some embodiments, the roller is engageable with the surface to be cleared in the second state of the auger housing to adjust the position of the leading edge of the auger housing relative to the surface to be cleared independently from the skid shoe. In some embodiments, the skid shoe is one of two skid shoes such that each skid shoe is mounted to a corresponding side of the auger housing, and the roller is one of two rollers such that the snow blower includes a corresponding roller on each side of the auger housing.

[0006] In another embodiment, the invention provides a snow blower including a prime mover, at least one ground engaging element, an auger housing, an auger system, a ground clearance assembly, and a locking mechanism. The at least one ground engaging element is operable under the influence of the prime mover for moving the snow blower over a surface to be cleared. The auger housing has a leading edge and an opening over the leading edge to collect snow from the surface to be cleared into the auger housing. The auger system is at least partially within the auger housing and is operable under the influence of the prime mover to blow the snow that is collected into the auger housing in a desired direction. The ground clearance assembly includes a pivot arm and a locking mechanism. The pivot arm is pivotally mounted to the auger housing. The pivot arm is pivotable between a stowed condition and a deployed condition. The locking mechanism is engaged with the pivot arm. The locking mechanism has an actuator and a spring that biases the actuator to selectively lock the pivot arm in the stowed condition or the deployed condition. The actuator is movable against the bias of the spring to selectively unlock the pivot arm from the stowed condition or the deployed condition.

[0007] In some embodiments, the ground clearance assembly includes a roller that is spaced from the surface to be cleared in the stowed condition and engages the surface to be cleared in the deployed condition. The roller engages the surface to be cleared at a location between the leading edge of the auger housing and the at least one ground engaging element. In some embodiments, the snow blower further includes a plate coupled to the auger housing. The plate defines a locking aperture in a portion of the plate that is cantilevered from the auger housing. In some embodiments, the actuator includes a head that is graspable and a sleeve extending from the head. The sleeve is biased by the spring. In some embodiments, the ground clearance assembly includes a pivot arm that defines a slot having circular ends. One of the circular ends is sized to receive the sleeve of the actuator when the pivot arm is in the stowed condition, and another one of the circular ends is sized to receive the sleeve of the actuator when the pivot arm is in the deployed condition. In some embodiments, the ground clearance is adjustable when the pivot arm is in the deployed condition such that the auger housing is raisable to a plurality of different positions when the ground clearance assembly is in the deployed condition.

[0008] Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Fig. l is a front top right perspective view of a snow blower including a ground clearance assembly according to the present invention.

[0010] Fig. 2 is an exploded view of the ground clearance assembly on the left side of the snow blower.

[0011] Fig. 3 is a view of a portion of the left side of the snow blower with the ground clearance assembly in a first position.

[0012] Fig. 4 is the same view as Fig. 3 with the ground clearance assembly in a second position.

[0013] Fig. 5 is a view of a portion of the left side of the snow blower with a ground clearance assembly according to another embodiment of the invention, the ground clearance assembly in a first deployed condition.

[0014] Fig. 6 is the same view as Fig. 5 with the ground clearance assembly in a second deployed condition.

DETAILED DESCRIPTION

[0015] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.

[0016] Fig. 1 illustrates a snow blower 10 having a frame 15, a prime mover 20 mounted to the frame 15, a pair of ground engaging elements 25 supporting the frame 15, an auger assembly 30, a chute 35, a deflector cap 40, a handle assembly 45, a pair of skid shoes 50, and a ground clearance assembly 55. Directions such as forward, rearward, left, and right will be used from the perspective of a user of the snow blower 10 during ordinary operation. Forward motion or direction of travel is indicated with arrow 60. [0017] The snow blower 10 is used to clear snow that has accumulated on a surface 65 to be cleared. As will be discussed below, the surface 65 may be a smooth, hard surface such as asphalt or concrete (e.g., a driveway, parking lot, or sidewalk) which may be scraped during the snow removal to clear down to the surface 65. The surface 65 may also be a non-smooth surface such as a rough surface, a surface having loose particles, a hard surface with edges on which the snow blower may catch (e.g., cracked concrete, concrete with sunken or uneven sections, or hardpacked snow and ice that is uneven, a frozen body of water, a nature trail), or a surface that can be worn or damaged by such scraping action (e.g., grass, gravel, or a roofing material). When clearing snow from one of these non-smooth surfaces, it is desirable to not scrape the surface 65 but instead skim closely over the surface to clear most of the snow and leave only a thin layer of snow behind. As should be apparent from the above description, the terms “ground” and “surface to be cleared” include manmade structural surfaces and natural surfaces over which the snow blower 10 travels and from which the snow blower 10 removes snow. The present invention permits the snow blower 10 to be easily switched between a mode in which the snow blower 10 scrapes the surface 65 and a mode in which the snow blower 10 does not scrape the surface 65 as the snow is being removed.

[0018] The frame 15 is of rigid construction and is conventional in the snow blower arts. The illustrated prime mover 20 is a conventional internal combustion engine powered by gasoline but in other embodiments is an electric motor powered by batteries. The illustrated ground engaging elements 25 are conventional drive wheels that are rotated under the influence of the prime mover 20 through a conventional transmission or drive system to move the snow blower 10 in the forward direction 60 over the surface 65. In other embodiments the ground engaging elements 25 are track assemblies including a track, a drive wheel, and a tensioner or idler. In other embodiments, the ground engaging elements 25 are a pair of right wheels rotating together under the influence of the prime mover 20 and a pair of left wheels rotating together under the influence of the prime mover 20 to achieve skid steering.

[0019] The illustrated auger assembly 30 is of a configuration known in the art as a two- stage configuration that operates under the influence of the prime mover 20. The auger assembly 30 includes an auger housing 30a and a main auger 30b toward the front of the machine inside a large front opening of the auger housing 30a. The main auger 30b rotates at a relatively slow rate about a horizontal axis perpendicular to the forward direction 60. The auger assembly 30 also includes a blower rearward of the main auger 30b, which rotates relatively fast about a horizontal axis parallel to the forward direction 60. The auger assembly 30 also includes a scraper bar 30c across the bottom of the auger housing 30a and rearward of the main auger 30b. The leading edge (i.e., front or forwardmost edge) of the scraper bar 30c extends perpendicular to the forward direction 60 and is selectively placed in contact with the surface 65 to generate the scraping action against the surface 65 mentioned above. The leading edge of the scraper bar 30c may be referred to as the leading edge of the snow blower 10 and the leading edge of the auger housing 30a because it is the forwardmost edge that is perpendicular to the forward direction 60.

[0020] As the snow blower 10 moves in the forward direction 60, snow that has accumulated on the surface 65 enters the auger assembly 30 and is moved toward the center by the main auger 30b and rearward toward the blower. The scraper bar 30c is angled upwardly from its leading edge so that snow also rides up the scraper bar 30c toward the blower. The blower launches the snow up through the chute 35 and deflector cap 40. The chute 35 rotates about a vertical chute axis and the deflector cap 40 pivots about a horizontal deflector axis. The positions of the chute 35 and deflector cap 40 determine the direction and angle at which the snow is launched from the snow blower 10.

[0021] The handle assembly 45 is attached to a rear end of the frame 15 and extends upwardly and rearwardly. An operator of the snow blower 10 grasps a pair of grips 45a at distal ends of the handle assembly 45 as the operator walks behind the snow blower 10. The handle assembly 45 also includes a control panel 45b where controls for speed, direction, chute angle, deflector cap angle, lights, auger engagement, and other snow blower operation are mounted. An operator zone is defined as the area occupied by the operator while grasping the grips 45a and standing or walking behind the snow blower 10 during ordinary operation of the snow blower 10 and everything within reach of the operator while in such position. The controls on the control panel 45b, for example, are within the operator zone.

[0022] Fig. 2 illustrates the skid shoe 50 and ground clearance assembly 55 on the left side of the snow blower 10, it being understood that the skid shoe 50 and ground clearance assembly 55 on the right side is a mirror image with identical or mirror image parts. The auger housing 30a includes first and second square holes 71, 72, and a circular hole 73 formed near a bottom edge of each sidewall of the auger housing 30a. First and second carriage bolts 81, 82, each having a square shoulder, extend through the respective first and second square holes 71, 72. Heads of the first and second carriage bolts 81, 82 abut an inner surface of the auger housing 30a sidewall and the square shoulders are received in the square holes 71, 72 to prevent rotation of the first and second carriage bolts 81, 82 with respect to the auger housing 30a sidewall. A third bolt 83 extends through the circular hole 73 with the head of the third bolt 83 engaging the inner surface of the sidewall. Threaded shanks of the first and second carriage bolts 81, 82 and the third bolt 83 extend sideways from the auger housing 30a to define horizontal axes that are perpendicular to the forward direction 60 and parallel to the leading edge of the scraper bar 30c.

[0023] The snow blower 10 also includes a rectangular stiffening plate 85 made of rigid material such as steel. The stiffening plate 85 is relatively thick compared to the thickness of the auger housing 30a sidewall. When mounted to the sidewall, the stiffening plate 85 provides a mounting location for the skid shoe 50 and ground clearance assembly 55. The stiffening plate 85 provides greater structural stability than could be provided by the relatively thin sidewall by itself. The stiffening plate 85 includes first and second square holes 85a, 85b, a pivot mounting hole 85c, and a locking mechanism hole 85d.

[0024] The stiffening plate 85 is mounted to the auger housing 30a sidewall with the square shoulders of the first and second carriage bolts 81, 82 received in the first and second square holes 85a, 85b and the third bolt 83 extending through the pivot mounting hole 85c. The stiffening plate 85 extends rearwardly in cantilever fashion from the auger housing 30a sidewall. The locking mechanism hole 85d is in the cantilevered portion of the stiffening plate 85 rearward of the auger housing 30a sidewall. The distance between the center of the pivot mounting hole 85c and the center of the locking mechanism hole 85d is also referred as the pivot radius as will be explained below.

[0025] The skid shoe 50 has a lower surface 50a designed to glide over the surface 65. The lower surface 50a may be a low friction, wearable material such as plastic or may be more durable such as steel. The skid shoe 50 includes two vertical slots 50b, 50c that receive the carriage bolts 81, 82 such that skid shoe 50 is adjusted vertically with respect to the sidewall of the auger housing 30a within the range of motion permitted by the carriage bolts 81, 82 traveling within the vertical slots 50b, 50c. The skid shoe 50 is adjusted to position the leading edge of the scraper bar 30c into engagement with the surface 65 and then securely fixed to the auger housing 30a with nuts and washers that sandwich the skid shoe 50, stiffening plate 85, and auger housing 30a sidewall together. With both skid shoes 50 properly adjusted and secured, the leading edge of the scraper bar 30c provides a scraping action against the surface 65 to be cleared when the auger housing 30a rests on the lower surface 50a of the skid shoes 50. When properly adjusted, the skid shoes 50 bear most of the weight of the auger housing 30a and the leading edge of the scraper bar 30c bears only enough weight to achieve the desired scraping action.

[0026] The ground clearance assembly 55 includes a pivot arm 110, locking mechanism 115, and a roller 120. The pivot arm 110 includes a pivot hole 110a in a proximal end, an arcuate slot 110b in a middle portion, and a roller mounting hole 110c in a distal end. The spacing between the center of the pivot hole 110a and an arc centered in the arcuate slot 110b is equal to the pivot radius (i.e., equal to the distance between the pivot mounting hole 85c and the locking mechanism hole 85d discussed above). The pivot hole 110a receives an end of the third bolt 83 which defines a horizontal pivot axis 83a for the pivot arm 110. The horizontal pivot axis 83a is parallel to the leading edge of the scraper bar 30c and perpendicular to the forward direction 60 of the snow blower 10.

[0027] The horizontal pivot axis 83a is a first height above the surface 65 to be cleared, and the leading edge of the scraper bar 30c is a second height above the surface 65 to be cleared. As will be discussed below, the second height may be essentially zero in one mode of operation in which the leading edge of the scraper bar 30c scrapes against the top surface 65, but in such modes the leading edge of the scraper bar 30c is technically above the surface 65. In another mode the leading edge of the scraper bar 30c is spaced above the surface 65 so that the leading edge of the scraper bar 30c skims snow a small distance above the surface 65. The first height is larger than the second height. As such, the leading edge of the scraper bar 30c is positioned between the horizontal pivot axis 83a and the surface 65 to be cleared. A bushing secures the proximal end to the third bolt 83 in a manner that permits the pivot arm 110 to pivot about the horizontal pivot axis 83a with respect to the stiffening plate 85 and sidewall of the auger housing 30a. [0028] The arcuate slot 110b defines an arclength of a circle centered on the horizontal pivot axis 83a and having a radius equal to the pivot radius. The arcuate slot 110b has a width 1 lOd and terminates at each end with a circular end having a diameter 1 lOe that is wider than a width 1 lOd of the arcuate slot 110b. With the proximal end pivotably mounted to the third bolt 83, the locking mechanism hole 85d remains centered in the arcuate slot 110b as the pivot arm 110 pivots about the horizontal pivot axis 83a.

[0029] As best seen in Fig. 2, the roller mounting hole 110c is centered in the height of the trailing end, or distal end, of the pivot arm 110. Alternative roller mounting holes 110c’, 110c” are formed above and below the roller mounting hole 110c to permit the roller 120 to be mounted higher or lower on the pivot arm 110 if desired by the user.

[0030] The locking mechanism 115 includes a hex bolt 130, an actuator 135, a spring 140, and a cap nut 145. The hex bolt 130 is conventional and has a head and a shank. A portion of the shank adjacent the head is smooth and a portion spaced away from the head is a threaded end of the shank. The actuator 135 includes a head 135a that can be easily grasped by the operator (e.g, between the index and middle fingers of one hand) and a sleeve 135b extending from the head 135a. The sleeve 135b is cylindrical with an inner diameter sized to receive the shaft of the hex bolt 130. The sleeve 135b has an outer diameter that is wider than the slot width 1 lOd of the arcuate slot 110b but narrower than the circular end diameter 1 lOe. The shaft of the hex bolt 130 extends through the sleeve 135b, through the arcuate slot 110b, through the locking mechanism hole 85d of the stiffening plate 85, through the spring 140, and is threaded into the cap nut 145 on the backside of the stiffening plate 85.

[0031] The spring 140 coils around the end of the shaft of the hex bolt 130 and is compressed between the cap nut 145 and the stiffening plate 85. The spring 140 biases the cap nut 145 away from the stiffening plate 85 which slides the hex bolt 130 axially in the same direction. The head of the hex bolt 130 abuts the head 135a of the actuator 135 to push the actuator 135 toward the pivot arm 110 and stiffening plate 85. With the end of the sleeve 135b biased by the spring 140 against the pivot arm 110 over the arcuate slot 110b, the pivot arm 110 can be pivoted about the horizontal pivot axis 83a. As the pivot arm 110 pivots, the end of the sleeve 135b slides along the pivot arm 110 until the sleeve 135b registers with one of the circular ends of the arcuate slot 110b at which time the biasing force of the spring 140 snaps the sleeve 135b into the circular end of the arcuate slot 110b. With the sleeve 135b received one of the circular ends, the pivot arm 110 is locked against pivotal movement with respect to the stiffening plate 85 and auger housing 30a. As will be discussed below, the roller 120 is locked in a stowed condition when the sleeve 135b is in one circular end of the arcuate slot 110b and is locked in a deployed condition when the sleeve 135b is in the other circular end of the arcuate slot 110b.

[0032] The pivot arm 110 is unlocked from the stowed or deployed condition by the operator pulling the sleeve 135b out of the circular end of the arcuate slot 110b (e.g., by grasping and pulling on the head 135a of the actuator 135). The operator slides the actuator 135 axially which also slides the hex bolt 130 axially because the head of the hex bolt 130 abuts the head 135a of the actuator 135. As the hex bolt 130 slides axially with respect to the pivot arm 110 and the stiffening plate 85, the spring 140 is compressed between the cap nut 145 and the stiffening plate 85 to generate the biasing force discussed above which will cause the sleeve 135b to automatically snap into one of the circular ends of the arcuate slot 110b when the sleeve 135b registers with the circular end.

[0033] The roller 120 is mounted to the pivot arm 110 with a conventional hex bolt 150 that extends through the roller mounting hole 110c or one of the alternative roller mounting holes 110c’, 110c” if it is wished to mount the roller 120 higher or lower on the pivot arm 110. The hex bolt 150 has a head and a shank that is smooth between the head and a threaded end of the shank. This hex bolt 150 may be the same part as the hex bolt 130 used for the locking mechanism 115. The hex bolt 150 extends through the center of the roller 120 and acts as an axle for the roller 120. The hex bolt 150 defines a roller axis 150a that is perpendicular to the forward direction 60 And parallel to the leading edge of the scraper bar 30c. A nut is threaded onto the threaded end of the hex bolt 150 to secure it to the roller 120 and pivot arm 110 and low friction washers 155 or bearings are positioned immediately adjacent the opposite sides of the roller 120 (i.e., between the roller 120 and the hex head of the hex bolt 150 and between the roller 120 and the pivot arm) to promote smooth rolling of the roller 120 on the hex bolt 150.

[0034] With reference to Fig. 3, the ground clearance assembly 55 is in a stowed condition when the pivot arm 110 is pivoted up and the sleeve 135b is received in the lower circular end of the arcuate slot 110b. In the stowed condition, both skid shoes 50 are in contact with the surface 65 and the leading edge of the scraper bar 30c may provide a scraping action against the surface 65. Additionally, in the stowed condition, the roller 120 is pivoted out of engagement with the surface 65. In some instances, the skid shoe 50 may be adjusted along the slot 50b relative to the auger housing 30a to raise the auger housing 30a from the surface 65. In such instances, the leading edge of the scraper bar 30c may not directly engage the surface 65 but may still provide a clearing action for material on the surface 65. For example, the scraper bar 30c may skim snow just above the surface 65 when the skid shoe 50 has been adjusted to raise the auger housing 30a from the surface 65.

[0035] With reference to Fig. 4, the ground clearance assembly 55 is in a deployed condition when the pivot arm 110 is pivoted down and the sleeve 135b is received in the upper circular end of the arcuate slot 110b. In the deployed condition, the roller 120 is pivoted into engagement with the surface 65 to be cleared to raise both skid shoes 50 and the leading edge of the scraper bar 30c off the surface 65, so the scraper bar 30c does not provide the scraping action against the surface 65 but instead skims snow just above the surface 65. The roller 120 engages the surface 65 at a location between the scraper bar 30c and the ground engaging elements 25 of Fig. 1. If the user wishes the skimming height of the scraper bar 30c to be lower, the hex bolt 150 for the roller 120 is positioned in the higher alternative roller mounting hole 110c’ and if the user wishes the skimming height to be higher, the hex bolt 150 is positioned in the lower alternative roller mounting hole 110c”. In the deployed condition, a majority of the weight of the auger housing is carried by the rollers 120.

[0036] Figs. 5 and 6 illustrate another embodiment of a ground clearance assembly 255 for the snow blower 10. The ground clearance assembly 255 is substantially similar to the ground clearance assembly 55 of Fig. 2 except for the differences described herein. As illustrated in Figs. 5 and 6, the ground clearance assembly 255 is selectively engageable with a surface 265 to be cleared. The ground clearance assembly 255 is mounted to the auger housing 30a, as described above with respect to Fig. 2, and includes a pivot arm 310, a locking mechanism 315, and a roller 320. The pivot arm 310 has an arcuate slot 3 lOd with a first end 360 and a second end 365. The first end 360 includes a first circular portion 360a and a second circular portion 360b that is positioned along the arcuate slot 3 lOd between the first circular portion 360a and the second end 365 of the arcuate slot 3 lOd. The second circular portion 360b partially overlaps the first circular portion 360a. The first circular portion 360a, the second circular portion 360b, and the second end 365 are each shaped to receive the locking mechanism 315.

[0037] As illustrated in Fig. 5, the first circular portion 360a of the first end 360 is configured to receive the locking mechanism 315 when the pivot arm 310 is in a first deployed condition in which the ground clearance assembly 255 raises the auger housing 30a a first distance DI from the surface 265 to be cleared.

[0038] As illustrated in Fig. 6, the second circular portion 360b of the first end 360 is configured to receive the locking mechanism 315 when the pivot arm 310 is in a second deployed condition in which the ground clearance assembly 255 raises the auger housing 30a a second distance D2 from the surface 265 to be cleared.

[0039] Referring again to both Figs. 5 and 6, the first distance DI is larger than the second distance D2. As such, the overlapping first circular portion 360a and second circular portion 360b enable an operator to vary the distance between the auger housing 30a and a surface 265 to be cleared when the pivot arm 310 is in the deployed condition.

[0040] Although the invention has been described with reference to certain embodiments, variations and modifications exist within the spirit and scope of the invention. Various features of the invention are set forth in the following claims.