Patent Application
20130291412
The present invention is directed to snow removal devices, and more particularly, to a snow thrower having two distinct stages of transferring and expelling loosened snow.
Snow removal machines typically include housings with a forward opening through which material enters the machine. At least one rotatable member (auger) is positioned and rotatably secured within the housing for engaging and eliminating the snow from within the housing. Snow blower technology is generally focused on designs whereby flighted augers move snow axially toward an impeller that is driven integrally (single stage) or independently driven (two-stage). Impellers are usually devices such as discs and blades that are shaped and configured such that when rotated they receive materials (snow) and then centrifugally discharge the materials through openings in the housings and then into chutes that control and direct the materials.
The known single stage and two-stage snow throwers have limitations in performance which often result from the augers typically moving material axially and impellers centrifugally, wherein the transition volume between the augers and impellers requires a tertiary force such as forward propulsion of the housing toward the materials to push the material into the impeller(s). Two-stage impellers separate the drive means of the augers and impellers so that each can operate at slower or higher speeds that improve their effectiveness, but in so doing, a transition volume is created. A need therefore exists for a snow thrower that reduces or eliminates the necessity of forward propulsion by the operator that also increases the operational efficiency of the snow thrower.
According to one aspect of the present invention, a two-stage snow thrower is provided. The two-stage snow thrower includes a power supply, a housing extending from the power supply, and a chute extending from the housing from which snow is thrown from the housing. A longitudinal drive shaft is positioned at least partially within the housing. The longitudinal drive shaft is rotatable by the power supply and extending from the power supply to a gear assembly. A lateral drive shaft is operatively connected to opposing side walls of the housing. The lateral drive shaft is also operatively connected to the gear assembly, wherein the longitudinal drive shaft is rotatably connected to the lateral drive shaft within the gear assembly. A first stage assembly includes at least two augers operatively connected to the lateral drive shaft, wherein at least one of the at least two augers is positioned adjacent to both opposing sides of the gear assembly. A second stage assembly for expelling the snow from the housing, the second stage assembly including an impeller operatively connected to the longitudinal drive shaft. At least one paddle is operatively connected to each of the augers positioned adjacent to opposing sides of the gear assembly.
According to another aspect of the present invention, a two-stage snow thrower is provided. The two-stage snow thrower includes a power supply, a housing extending from the power supply, and a chute extending from the housing for allowing snow to be expelled from the housing through the chute, wherein the housing includes an exit aperture from which the chute extends. A longitudinal drive shaft is positioned within the housing, the longitudinal drive shaft is selectively rotatable by the power supply and extending between the power supply and a gear assembly. A lateral drive shaft is rotatably connected to opposing side walls of the housing. The lateral drive shaft is operatively connected to the gear assembly, wherein the longitudinal drive shaft is rotationally connected to the lateral drive shaft. A first stage assembly includes two augers operatively connected to the lateral drive shaft, wherein each of the augers is positioned adjacent to opposing sides of the gear assembly. Each of the augers is formed of a base and at least one flight extending radially outward from the base, wherein the at least one flight is helically shaped relative to the lateral drive shaft. A second stage assembly includes an impeller positioned within the housing and operatively connected to the longitudinal drive shaft. At least one paddle is operatively connected to a peripheral edge of each flight of the augers.
According to a further aspect of the present invention, a two-stage snow thrower is provided. The two-stage snow thrower includes a power supply and a housing extending from the power supply. The housing includes a recess and the recess has an opening thereto. A chute extends from the housing for allowing snow to be expelled from the housing through the chute. A longitudinal drive shaft having one distal end operatively connected to the power supply and a second distal end operatively connected to a gear assembly. The longitudinal drive shaft is selectively rotatable by the power supply, wherein the longitudinal drive shaft includes a first worm gear adjacent to the second distal end. A lateral drive shaft has a second worm gear and is rotatably connected to opposing side walls of the housing. The lateral drive shaft is operatively connected to the gear assembly transversely with respect to the longitudinal drive shaft, wherein the first worm gear of the longitudinal drive shaft is operatively connected to the second worm gear of the lateral drive shaft for transferring rotation of the longitudinal drive shaft to the lateral drive shaft. A first stage assembly includes at least two augers operatively connected to the lateral drive shaft between the gear assembly and each of the opposing side walls of the housing. Each of the augers is formed of a base and a plurality of flights extending radially outward from the base and oriented helically relative to the lateral drive shaft. A second stage assembly includes an impeller positioned within the recess and operatively connected to the longitudinal drive shaft. A paddle is operatively connected to a peripheral edge of each flight of each auger positioned immediately adjacent to the gear assembly.
Advantages of the present invention will become more apparent to those skilled in the art from the following description of the embodiments of the invention which have been shown and described by way of illustration. As will be realized, the invention is capable of other and different embodiments, and its details are capable of modification in various respects.
These and other features of the present invention, and their advantages, are illustrated specifically in embodiments of the invention now to be described, by way of example, with reference to the accompanying diagrammatic drawings, in which:
It should be noted that all the drawings are diagrammatic and not drawn to scale. Relative dimensions and proportions of parts of these figures have been shown exaggerated or reduced in size for the sake of clarity and convenience in the drawings. The same reference numbers are generally used to refer to corresponding or similar features in the different embodiments. Accordingly, the drawing(s) and description are to be regarded as illustrative in nature and not as restrictive.
Referring to
The housing 18 is a generally semi-cylindrical, or C-shaped casing including a recess 20 extending rearwardly from the central C-shaped portion, wherein the housing 18 is longitudinally oriented in a transverse direction relative to the forward direction of movement of the snow thrower 10, as shown in
In the embodiment illustrated in
As shown in
The first stage assembly 32 of the two-stage snow thrower 10 includes at least two augers 34 attached to the lateral drive shaft 30, wherein at least one auger 34 is positioned on the lateral drive shaft 30 adjacent to each opposing side of the gear assembly 28, as shown in
Each auger 34 includes at least one flight 36 that extends radially outward from a base 38 as well as extending at least somewhat concentrically with the outer surface of the base 38. In the illustrated embodiment, the flights 36 include a base portion that extends radially from the base 38 in a generally linear manner, and an arc-shaped blade portion that expands from the end of the base portion in a generally semi-circular manner about the base 38. The blade portion of the flight 36 is also curved, or angled in a helical manner about the base 38. The blade portion of each flight 36 extends about the base 38 about one hundred eighty degrees (180) such that two flights 36 extending about the entire periphery of the base 38. In another embodiment, each auger 34 has a single flight 36 that extends about the entire periphery of the base 38 in a helical manner. In yet another embodiment, each auger 34 includes more than two flights 36 extending from the base 38 such that all of the flights 36 extend about at least the entire periphery of the base 38. The augers 34 can be formed of segmented or continuous flights 36, or the augers 34 may include brushes incorporated with the flights 36. It should be understood by one of ordinary skill in the art that the augers 34 are configured in a corkscrew or spiral shape or orientation relative to the lateral drive shaft 30 to which they are attached. For example, the augers 34 of the first stage assembly 32 are configure to rotate and push or transport the snow in the direction from the side walls of the housing 18 toward the centrally-located gear assembly 28.
In an exemplary embodiment, each auger 34 of the first stage assembly 32 that is attached to the lateral drive shaft 30 and positioned immediately adjacent to the gear assembly 28 includes at least one paddle 40 extending from the outer radial edge of a flight 36, as shown in
The paddle 40 extending from the flight 36 of an auger 34 is angled such that the paddle 40 is directed upstream, or toward the direction of rotation of the flight 36 to which it is attached. This orientation allows the paddle 40 to push the loosened snow rearward within the housing 18 as the snow thrower 10 is pushed or driven forwardly. The paddle 40 is configured to extend from at least a portion of the outer radial or peripheral edge of a flight 36. Because the flights 36 are helically- or spirally-shaped, the paddles 40 are arcuate and have a similar helical shape about the lateral drive shaft 30. In the illustrated embodiment, the paddle 40 extends from about a 15° portion or arcuate length of the peripheral edge of the flight 36, wherein the flight 36 extends helically about 180° around the lateral drive shaft 30. It should be understood by one of ordinary skill in the art that the paddle 40 can also extend from the entire peripheral edge of the flight 36 or any smaller portion of the outer peripheral edge.
In an embodiment, each paddle 40 is formed separately from the auger 34 and then attached to the auger 34 by welding. In another embodiment, each flight 36 is formed separately, and the paddle(s) 40 extending from the flight 36 is integrally formed with the flight 36. It should be understood by one of ordinary skill in the art that the paddle(s) 40 can be attached to the flights 36 in any manner sufficient to provide a joint which can withstand the temperature variations and stresses to which the augers 32 are subjected to during operation of the snow thrower 10. Whereas rotation of lateral drive shaft 30 results in rotation of the augers 34 attached thereto such that the snow is moved axially along the lateral drive shaft 30 toward the gear assembly 28, the paddles 40 are configured to assist the loosened snow in being moved rearward toward the second stage assembly 42 which is transversely relative to the lateral drive shaft 30.
In an embodiment, the second stage assembly 42 includes a rotatable impeller 44 operatively connected to the longitudinal drive shaft 26 and positioned within the recess 20, as shown in
As shown in
The gear assembly 28 is configured to transfer the rotational power from the power supply 12 via the longitudinal drive shaft 26 to the lateral drive shaft 30, as shown in
In an embodiment, the snow thrower 10 also includes a baffle 54 positioned within and attached to the housing 18 such that it surrounds the opening to the recess 20, as shown in
The longitudinal drive shaft 26 is powered by the power supply 12 such that the longitudinal drive shaft rotates between about 50 to about 1500 RPM. The rotational power of the longitudinal drive shaft 26 is transferred to the lateral drive shaft 30 by way of the gear assembly 28. In the illustrated exemplary embodiment, the gear assembly 28 is configured to transfer rotational power from the longitudinal drive shaft 26 to the lateral drive shaft 30, whereby the lateral drive shaft 30 can rotate at the same rotational velocity as the longitudinal drive shaft 26, a slower rotational velocity relative to the longitudinal drive shaft 26, or a faster rotational velocity relative to the longitudinal drive shaft 26. As the augers 34 of the first stage assembly 32 rotate about a lateral rotational axis, these augers 34 break up the accumulated snow and ice and push this loosened snow axially toward the gear assembly 28 positioned near the center of the housing 18. In combination with the forward movement of the snow thrower 10, the paddles 40 attached to the augers 34 of the first stage assembly 32 push the loosened snow rearwardly toward the impeller 44 of the second stage assembly 42. As the loosened snow is pushed into the second stage assembly 42, the impeller 44 rotates at a sufficient rotational velocity to push or throw the snow in a radially outward manner through the chute 16 and away from the snow thrower 10. The baffle 54 reduces or eliminates re-circulation of the snow within the second stage assembly 42, thereby increasing the efficiency of the snow thrower 10.
Rotation of the augers 34 of the first stage assembly 32 causes accumulated snow and ice to break up and become more easily moveable within the housing 18. The axial rotation of the augers 34 in combination with the rotation of the paddles 40 which assist in pushing loosened snow rearward within the housing 18 pulls the snow and ice into the housing 18, thereby reducing the amount of forward or longitudinal thrust that must be applied to the snow thrower 10 by the operator. The rotation of the augers 34 and paddles 40 of the first stage assembly 32 also generates a forward thrust that reduces the possibility of loss of drive traction of the wheels and “ride up” in which the wheels stay on the ground while the housing raises up by itself.
While preferred embodiments of the present invention have been described, it should be understood that the present invention is not so limited and modifications may be made without departing from the present invention. The scope of the present invention is defined by the appended claims, and all devices, processes, and methods that come within the meaning of the claims, either literally or by equivalence, are intended to be embraced therein.
