Patent Description:
Grass mowing machines used to mow golf courses, parks, and athletic fields where a high quality of cut is desired, may include three or more reel cutting units. Triplex greensmowers have two forward reel cutting units followed by a center or rear reel cutting unit positioned under the vehicle frame and in front of the operator station. Each reel cutting unit on a triplex greensmower may be mounted to a lift arm that may be used to raise and lower the cutting unit between a mowing position and a transport position. Reel cutting units have front and rear rollers, spiral cutting blades rotating in close proximity to a bedknife, and may have a removable grass catcher mounted in front of the cutting unit.

<CIT> shows a front rotary cutting deck having folded service positions. A cutting deck is suspended beneath a carrier frame by a height of cut adjustment system comprising a plurality of pivot links and suspension chains extending between the carrier frame and the cutting deck. A hydraulic cylinder coupled to one of the pivot links can simultaneously lift the chains or permit the chains to lower to change the height of the cutting deck relative to the carrier frame. This same cylinder can also fold the carrier frame and the cutting deck relative to the traction unit about a fold pivot axis when a fold latch is selectively released by the operator.

There is a need for a triplex greensmower that provides better quality of cut and reduces the tendency of reel cutting units to leave marks or step cuts on the turf. There is a need for a triplex greensmower that reduces the impact of each reel cutting unit when it is lowered to the mowing position with the front and rear rollers parallel to the ground to distribute the load evenly. There is a need for a triplex greensmower that eliminates the pendulum effect in which reel cutting units tend to swing from the lift arms. There also is a need for a triplex greensmower that provides improved access to the center or rear reel cutting unit for service, and for emptying and replacing the grass catcher.

A triplex greensmower open foot platform includes a left platform section and a right platform section, each section removably attached to a triplex greensmower with a coupling extending rearwardly from the section and that is slidable into a frame member of the triplex greensmower. The left platform section and the right platform section define the perimeter of an opening in front of an operator seat on the triplex greensmower that has a larger length and width than a center reel cutting unit or a grass catcher attached thereto. The left platform section and the right platform section each include a foot rest and a narrower neck portion extending from the foot rest. The triplex greensmower open foot platform provides improved access to the center or rear reel cutting unit for service, and for emptying and replacing the grass catcher.

In a first embodiment shown in <FIG>, triplex greensmower <NUM> includes left and right front reel cutting units <NUM>, <NUM> positioned side-by-side forwardly of left and right drive wheels <NUM>, <NUM>, and center or rear reel cutting unit <NUM> positioned behind the drive wheels and in front of steerable rear wheel <NUM>. Grass catchers <NUM>, <NUM> and <NUM> may be removably attached to the front of each of the reel cutting units. An electric or hydraulic motor may drive each cutting reel and may be mounted to one side of the reel cutting unit. The triplex greensmower may have operator seat <NUM> between the drive wheels and rear wheel, console <NUM> adjacent the operator seat, and roll over protection system or ROPS <NUM> attached to the frame behind and alongside the operator seat. Step <NUM> may be mounted to the frame of the triplex greensmower to the left side and below the operator seat, and steering wheel <NUM> may be mounted on steering column <NUM> to the right and in front of the operator seat.

In one embodiment, as shown in <FIG>, triplex greensmower <NUM> may include open foot platform <NUM> having a left platform section <NUM> and right platform section <NUM>. The left and right platform sections may be metal castings, molded plastic, composite or other materials that define the perimeter of an opening <NUM> in front of operator seat <NUM>. From the operator seat, an operator may have an unobstructed sight line through opening <NUM> in triplex greensmower open foot platform <NUM> for visibility of grass catcher <NUM> and center cutting unit <NUM>. An operator also may lift the grass catcher through the opening in the triplex greensmower open foot platform for emptying and replacement. Additionally, an operator may use the opening in the triplex greensmower open foot platform to service the center cutting unit, and may remove or replace the center cutting unit through the opening. The opening in the triplex greensmower open foot platform may have width and length dimensions larger than the width and length of the center reel cutting unit or grass catcher. For example, the opening may have side-to-side and front-to-back dimensions of <NUM> inches and <NUM> inches respectively, which may be larger than dimensions of the reel cutting unit or grass catcher.

In an alternative embodiment, the triplex greensmower open foot platform may have a single platform section instead of left and right platform sections. The single platform section may extend partially or completely around the opening for the center cutting unit.

In one embodiment, as shown in <FIG>, triplex greensmower open foot platform <NUM> may include left and right platform sections <NUM>, <NUM>, at least one of the platform sections being removable from the triplex greensmower without requiring tools. For example, at least one of the platform sections may include a coupling <NUM> that extends rearwardly from the platform section and may be used by the operator to manually engage and disengage the platform section from the triplex greensmower frame. Each coupling <NUM> may include a base portion <NUM> and a post <NUM> extending from the base. Each post <NUM> may slide into one end of main frame support tube <NUM>, and each base portion <NUM> may slide into channel <NUM> extending over the end of the main frame support tube. The base portion and channel each may have rectangular cross sections to prevent twisting or pivoting of each coupling relative to the frame.

In one embodiment, triplex greensmower open foot platform <NUM> may be locked or secured to the triplex greensmower frame. For example, one or more locking members <NUM>, <NUM> such as a bolt, pin or fastener, may be inserted through holes aligned in coupling <NUM>, and in main frame support tube <NUM> and/or channel <NUM>.

In one embodiment, the triplex greensmower open foot platform may include a latch <NUM> to lock or secure together the left and right platform sections <NUM>, <NUM> when both sections are engaged to the triplex greensmower frame. For example, latch <NUM> may be provided on the forward end of right platform section <NUM> and may capture an abutment <NUM> on the forward end of left platform section <NUM>. Alternatively, a slot and tab or other mechanism may be used for securing or locking together the left and right platform sections. Securing or locking together the left and right platform sections also helps prevent disengagement of each coupling <NUM> from main frame support tube <NUM> and channel <NUM>.

In one embodiment, the triplex greensmower open foot platform may include left and right footrests <NUM>, <NUM>, and neck portions <NUM>, <NUM>, <NUM> extending from or between the left and right footrests. The neck portions may be narrower than the footrests. Additionally, one or more openings <NUM>, <NUM> may be provided through the neck portions to provide the operator with unobstructed sight lines and visibility to the front reel cutting units. For example, the neck portions may include parallel bars <NUM>, <NUM> that are spaced apart.

In a second embodiment shown in <FIG>, triplex greensmower open foot platform <NUM> may include left and right platform sections <NUM>, <NUM>, and opening <NUM>. In the second embodiment, the left and right platform sections may not be secured or locked together. The second embodiment also may not include a neck portion or latch extending between the left and right platform sections. Each of the left and right platform sections may include a coupling <NUM> that includes a base portion <NUM> and a post <NUM>. Each post <NUM> may slide into one end of main frame support tube <NUM>, and each base portion <NUM> may slide into channel <NUM> extending over the end of the main frame support tube. The base and channel may have rectangular cross sections to prevent twisting or pivoting of the coupling relative to the frame. One or more locking members <NUM>, such as a bolt, pin or fastener may lock either coupling to the frame.

In one embodiment, as shown in <FIG>, triplex greensmower <NUM> may include lift system <NUM> for each reel cutting unit. Each lift system <NUM> may allow each reel cutting unit to follow ground contours when mowing, and may be used to raise and lower a reel cutting unit between the mowing and transport position. Each lift system <NUM> may include roll axis <NUM> where upper lift arm <NUM> may be pivotably mounted to lower lift arm <NUM>. Roll axis <NUM> may be behind the reel cutting unit, at a height or elevation between the top of the cutting unit and the center of gravity (CG) of the cutting unit, and preferably within about <NUM> of the CG. Each lift system <NUM> may include yaw axis <NUM> which may be where yoke mount <NUM> is connected to the forward end of upper lift arm <NUM>, in front of the CG of the cutting unit. Each lift system <NUM> also may include lift axis <NUM> where lower lift arm <NUM> may be pivotably mounted to the vehicle frame behind the cutting unit, lifter support axis <NUM> where lifter support <NUM> may be pivotably mounted to lower lift arm <NUM>, and cutting unit mounting axis <NUM> where yoke mount <NUM> may be pivotably connected to the reel cutting unit side panels <NUM>, <NUM>. Each axis may be positioned at a different location relative to the CG of the cutting unit. The triplex greensmower lift system also may include a pair of flexible linkages <NUM>, <NUM> between lifter support <NUM> and the cutting unit to hold the cutting unit still when it is raised from the ground. Additionally, the lift system may include tension spring <NUM> connected between the forward end of upper lift arm <NUM> and triplex greensmower frame member <NUM> behind and above the reel cutting unit.

In one embodiment, triplex greensmower lift system <NUM> may include upper lift arm <NUM> that is pivotably mounted with bearings <NUM>, <NUM> to lower lift arm <NUM> behind the reel cutting unit. The mounting location of the upper lift arm provides a roll axis <NUM> that is between the top of the cutting unit and the center of gravity (CG) of the cutting unit, and preferably within about <NUM> from the CG of the cutting unit. From roll axis <NUM>, upper lift arm <NUM> may extend forwardly and upwardly where it may be attached to yoke mount <NUM>. Positioning the roll axis in close proximity to the cutting unit's CG minimizes gravity-induced positional displacement of the cutting unit when mowing on hillsides, reduces the possibility of unlapping (leaving uncut strips between cutting units), and reduces the pendulum effect, which is the tendency of a cutting unit to swing when raised in the transport position. Tension spring <NUM>, connected between the forward end of upper lift arm <NUM> and triplex greensmower frame member <NUM>, may provide stability to the roll of the cutting unit and also may reduce the tendency of the cutting unit to leave marks on the turf by transfer of weight of the cutting unit to the vehicle frame.

In one embodiment, triplex greensmower lift system <NUM> may include yoke mount <NUM> which provides yaw axis <NUM> to give the reel cutting unit a full range of steering as the vehicle turns on an axis perpendicular to the ground plane. The location of the yaw axis is forward of the CG of the reel cutting unit and preferably at least about <NUM> forward of the CG of the cutting unit. Yoke mount <NUM> may be pivotably connected to a sleeve on the forward end of upper lift arm <NUM>. A vertical bolt or rod <NUM> may be inserted through the yoke mount and sleeve, enabling the yoke mount to pivot on vertical yaw axis <NUM>. The front of yoke mount <NUM> may include a pair of channels or groove where upper rod <NUM> and lower rod <NUM> may be secured and clamped with clamping member <NUM>. The yoke mount does not provide a pitch axis at this location. Instead, the yoke mount may include yoke arms <NUM>, <NUM> attached to the ends of the upper and lower rods, and extending downwardly where they may be pivotably mounted to side panels <NUM>, <NUM> of the reel cutting unit at cutting unit mounting axis <NUM>. Cutting unit mounting axis <NUM> provides a pitch axis for the reel cutting unit that is below and forward of the reel cutting unit's CG. Additionally, clamping member <NUM> may be loosened and releases to allow shifting the reel cutting unit left or right relative to the yoke mount. A stop may be provided on at least one of the rods to define a desired position.

In one embodiment, triplex greensmower lift system <NUM> may include lift axis <NUM> between lower lift arm <NUM> and the triplex greensmower frame, lifter support axis <NUM> between lifter support <NUM> and lower lift arm <NUM>, and cutting unit mounting axis <NUM> between yoke arms <NUM>, <NUM> and the cutting unit side panels <NUM>, <NUM>. Each of the lift axis <NUM>, lifter support axis <NUM> and cutting unit mounting axis <NUM> may provide a pitch axis that allows the reel cutting unit to follow ground contours by pitching on an axis that is horizontal and perpendicular to the direction of travel, and also may allow the reel cutting unit to stay approximately level when it is raised and lowered between the mowing position and transport position. Tension spring <NUM> also may bias the reel cutting unit upwardly relative to lift axis <NUM> and reduce ground pressure of the cutting unit on the turf during mowing. Preferably, the tension spring on the left front reel cutting unit may be connected at a location offset to the left side of the upper lift arm, and the tension spring on the right front reel cutting unit may be connected at a location offset to the right side of the upper lift arm. As a result, each of the tension springs may reduce ground pressure and prevent marks or step cuts by biasing the left side of the left front reel cutting unit upwardly during left turns, and biasing the right side of the right front reel cutting unit upwardly during right turns.

In one embodiment, triplex greensmower lift system <NUM> may include lifter support <NUM> and a pair of flexible linkages <NUM>, <NUM> that hold the reel cutting unit approximately level and prevent swinging of the cutting unit while it is raised to the transport position. To raise the cutting unit to the transport position shown in <FIG>, lift cylinder <NUM>, which may be a hydraulic cylinder or electric actuator, may be retracted. Lift cylinder <NUM> may be connected to lifter support <NUM>, and retraction of the lift cylinder pivots the lifter support upwardly on lifter support axis <NUM>. A pair of flexible linkages <NUM>, <NUM>, such as a pair of chains, may connect each leg of the U-shaped lifter support <NUM> to the reel cutting unit behind the cutting unit's center of gravity (CG). Yoke arms <NUM>, <NUM> may be pivotably connected to the reel cutting unit in front of its center of gravity. When the lift cylinder retracts, lifter support <NUM> may pull up the pair of flexible linkages <NUM>, <NUM> to raise the rear of the cutting unit while the yoke arms the front of the cutting unit. The lifter support and pair of flexible linkages also may hold the cutting unit approximately level, and prevent swinging of the cutting unit. After the lifter support reaches a stop, the lift cylinder may retract further to pivot up lower lift arm <NUM> and upper lift arm <NUM> on lift axis <NUM> to raise the cutting unit to the transport position. Tension spring <NUM>, connected between the upper lift arm and frame member <NUM>, may assist the lift cylinder when raising the cutting unit to the transport position.

In one embodiment, triplex greensmower lift system <NUM> may hold the reel cutting unit approximately level and prevent swinging of the cutting unit while it is transported, and when it is lowered to the mowing position. To lower the reel cutting unit, lift cylinder <NUM> may be extended to pivot lower lift arm <NUM> and upper lift arm <NUM> downwardly together on lift axis <NUM>. Lifter support <NUM> and flexible linkages <NUM>, <NUM> may hold the cutting unit approximately level so that the rear of the cutting unit and rear roller <NUM> reach the turf along with the front of the cutting unit and front roller <NUM>. Tension spring <NUM> may dampen or reduce the impact of the cutting unit on the turf. As the cutting unit reaches the turf, lift cylinder <NUM> may extend further to pivot lifter support <NUM> downwardly on lifter support axis <NUM>, removing any tension in the pair of flexible linkages so the cutting unit can roll, yaw and pitch during mowing.

Claim 1:
A triplex greensmower comprising
a center reel unit (<NUM>),
a grass catcher (<NUM>),
an operator seat (<NUM>),
an open foot platform (<NUM>), comprising:
a pair of removable platform sections (<NUM>, <NUM>) configured to engage a frame member (<NUM>) of the triplex greensmower so that the sections (<NUM>, <NUM>) cannot twist or pivot with respect to the frame member (<NUM>); each of the sections (<NUM>, <NUM>) including a foot rest (<NUM>, <NUM>);
characterized by an opening (<NUM>) in front of the operator seat, between the pair of removable platform sections (<NUM>, <NUM>), configured so that the center reel unit (<NUM>) can be serviced or the grass catcher (<NUM>) can be lifted through the opening (<NUM>, <NUM>) having larger dimensions than the center reel unit (<NUM>); and a lock (<NUM>, <NUM>) securing at least one of the pair of removable platform sections (<NUM>, <NUM>) to the frame member (<NUM>).