FIELD OF THE INVENTION
This invention relates generally to stand on mowers, and specifically to a compact stand on mower deck belt system.
BACKGROUND OF THE INVENTION
Stand on mowers are used for commercial and residential mowing. Like zero turning radius mowers, they have a pair of independently driven rear traction drive wheels controlled by a pair of steering levers. Compact stand on mowers may have mower decks under 40 inches in width to fit through gates, tight openings, around trees or obstacles. These mower decks have two rotary blades. Compact stand on mowers also may have a short length to minimize storage space on trailers, sheds or garages, and may be relatively light in weight. Compact stand on mowers may have an engine mounted rigidly to the vehicle frame in front of the operator station and over the mower deck. The angle of the belt that transmits power from the engine to the mower deck may be referred to as the fleet angle which may increase when the mower deck is raised or lowered, because the engine is close to the mower deck.
There is a need for an improved compact stand on mower deck belt system that extends belt life by having a low fleet angle. There is a need for an improved compact stand on mower deck belt system that lowers belt stress, provides cooler running belts, and reduces belt friction and dislodgement from pulleys.
SUMMARY OF THE INVENTION
A compact stand on mower deck belt system includes an engine driveshaft extending downwardly over a rear portion of a mower deck with an engine driveshaft pulley attached thereto. A first deck belt engages the engine driveshaft pulley and a first blade spindle pulley. A second deck belt engages the first blade spindle pulley and a second blade spindle pulley. At least one of an idler pulley and a tensioner pulley is mounted to a front portion of the mower deck and engages the first deck belt between the engine driveshaft pulley and the first blade spindle pulley. This provides a reduced fleet angle for a two deck belt system on a stand on mower.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a stand on mower with a deck belt system according to a first embodiment of the invention.
FIG. 2 is a perspective view of a stand on mower deck belt system according to a first embodiment of the invention.
FIG. 3 is a top view of a sand on mower deck belt system according to a first embodiment of the invention.
FIG. 4 is side view, partially in cross section, of a stand on mower deck belt system at the lowest cutting height, according to a first embodiment of the invention.
FIG. 5 is a side view, partially in cross section, of a stand on mower deck belt system at the highest cutting height, according to a first embodiment of the invention.
FIG. 6 is a side view, partially in cross section, of a stand on mower deck belt system at an intermediate cutting height between the lowest and highest cutting heights, according to a first embodiment of the invention
DESCRIPTION OF THE PREFERRED EMBODIMENT
In one embodiment shown in FIGS. 1-6, compact stand on mower deck belt system 100 may be on compact stand on mower 101 having floating mower deck 102, operator station 104, and internal combustion engine 106 or other power source. The engine or other power source may be stationary or mounted rigidly to the compact stand on frame 108 in front of the operator station, and above mower deck 102. Front caster wheels 112 may support the forward end of frame 108. Mower deck 102 may have two blade spindles 105, 107 mounted thereto, with a rotary cutting blade attached to the lower end of each spindle. Mower deck 102 may have a width of 40 inches or less for fitting through gates, tight openings, around trees or obstacles. Lift system 109 may be used to raise or lower mower deck 102 between cutting heights of about 1.5 inches and about 5 inches.
In one embodiment shown in FIGS. 1-6, compact stand on mower deck belt system 100 may have first and second deck belts 114, 116. First deck belt 114 may transmit rotational power from pulley 140 on engine driveshaft 139 to pulley 120a on left blade spindle 105. Second deck belt 116 may transmit rotational power between pulley 120a on left blade spindle 105 and pulley 126 on right blade spindle 107. Each deck belt preferably may be a V-belt for engaging a V-groove in each pulley or sheave.
In one embodiment shown in FIGS. 1-6, compact stand on mower deck belt system 100 may include first deck belt 114 between driveshaft pulley 140 and first idler pulley 124 on mower deck 102. Engine driveshaft 139 and driveshaft pulleys 140, 141 may be located over the rear portion of the mower deck. First idler pulley 124 may be rotatably mounted on bracket 132 attached to the top surface of the mower deck adjacent the front center of the mower deck.
In one embodiment shown in FIGS. 1-6, compact stand on mower deck belt system 100 may include first deck belt 114 extending between first idler pulley 124 and second idler pulley 122. The first and second idler pulleys may be rotatably mounted to the front portion of mower deck 102, so that both idler pulleys are over the mower deck. Second idler pulley 122 may be rotatably mounted on bracket 132 attached to the top surface of the mower deck.
In one embodiment shown in FIGS. 1-6, compact stand on mower deck belt system 100 may include first deck belt 114 extending between second idler pulley 122 and upper pulley or sheave 120a on left blade spindle 105. The left blade spindle may be mounted to the mower deck rearward of the second idler pulley. Upper pulley or sheave 120a may be spaced above lower pulley or sheave 120b on left blade spindle 105. The left blade spindle may extend through the mower deck where a rotary mower blade may be attached thereto.
In one embodiment shown in FIGS. 1-6, compact stand on mower deck belt system 100 may include first deck belt 114 extending between upper pulley or sheave 120a on left blade spindle 105, and tensioner pulley 118. The tensioner pulley may be rotatably mounted on tensioner arm 136. Tensioner arm 136 may be pivotably mounted to the top front surface of the mower deck, forwardly of the left blade spindle and between the left and right idler pulleys. Tensioner spring 134 may tension first deck belt 114 by biasing tensioner arm 136 toward the front of the mower deck and tensioner pulley 118 against the back side of the first deck belt. Tensioner pulley 118 may have a flat width such as 2 inches so the back side of first deck belt 114 may ride up or down on the tensioner pulley.
In one embodiment shown in FIGS. 1-6, compact stand on mower deck belt system 100 provides a two belt system with a reduced fleet angle of the belt between the engine driveshaft and mower deck. For example, first deck belt 114 has a maximum fleet angle of less than about 7 degrees. The maximum fleet angle may be measured between drive pulley 140 and a pulley mounted to the mower deck. In this compact stand on mower deck belt system, the maximum fleet angle is between drive pulley 140 and tensioner pulley 118 or first idler pulley 124. The maximum fleet angle may be when the mower deck is raised to its lowest height of cut, such as 1.5 inches, or raised to its highest height of cut, such as 5.0 inches. The minimum fleet angle may be 0 degrees at an intermediate height of cut, such as 3.25 inches, where the drive pulley is at the same height as the tensioner pulley and first idler pulley.
In one embodiment shown in FIG. 4, compact stand on mower deck belt system 100 may have a maximum fleet angle Θ1 of 5.48 degrees at the mower deck's highest height of cut setting of 5.0 inches. The fleet angle at the highest height of cut setting of 5.0 inches is based on first idler pulley 124 that is raised to 1.75 inches (44.45 mm) above drive pulley 140, and a belt length between the first idler pulley and drive pulley of 18.2 inches (463 mm). This results in a fleet angle of 5.48 degrees.
In one embodiment shown in FIG. 5, compact stand on mower deck belt system 100 may have a maximum fleet angle Θ2 of 6.86 degrees at the mower deck's lowest height of cut setting of 1.5 inches. The fleet angle at the lowest height of cut setting of 1.5 inches is based on tensioner pulley 118 that is lowered to 1.75 inches (44.45 mm) below drive pulley 140, and a belt length between the tensioner pulley and drive pulley of 14.5 inches (369 mm). This results in a fleet angle of 6.86 degrees. The fleet angle may be reduced to 4.95 degrees at the lowest height of cut if tensioner pulley 118 has a width of at least 2 inches as shown in FIG. 5.
In one embodiment shown in FIG. 6, compact stand on mower deck belt system 100 may have a fleet angle of 0 degrees at an intermediate cutting height between the mower deck's highest and lowest height of cut settings. At the intermediate cutting height, tensioner pulley 118 and first idler pulley 124 are at the same height as drive pulley 140.
In one embodiment shown in FIGS. 1-6, compact stand on mower deck belt system 100 may include second deck belt 116 which may transmit rotational power from left blade spindle 105 to right blade spindle 107. Second deck belt 116 may extend between lower pulley or sheave 120b on left blade spindle 105, and pulley or sheave 126 on right blade spindle 107. The right blade spindle may extend through the mower deck where a rotary mower blade may be attached thereto. Second deck belt 116 also may engage idler pulley 128 rotatably mounted on the mower deck between and forward of the left and right blade spindles. The compact stand on mower deck belt system may include a first mounting hole and a second mounting hole for idler pulley 128, for repositioning the idler pulley to increase tension of the second deck belt after extended use.
In one embodiment shown in FIGS. 1-6, compact stand on mower deck belt system also may include a third belt 115 to transmit rotational power from a second pulley or sheave 141 on engine driveshaft 139 to integrated hydrostatic transaxle 144 for left and right rear traction drive wheels 110.
Having described the preferred embodiments, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.