Abstract:
The invention provides a power take-off from a lawn mower, through a flexible drive shaft cable, to utilize lawn maintenance accessories. The power take-off allows the accessories (e.g. edgers and trimmers) to draw power from the lawn mower&#39;s engine. Flexible drive shafts provide rotary power transmission along curved, non-linear axes. The user can engage or disengage the accessory through use of an electrical or mechanical clutch. The clutch connects the lawn mower engine drive shaft to the flexible drive shaft so that they can either be locked together and spun at the same speed, or decoupled and spun at different speeds. Engaging the clutch transfers power from the lawn mower engine to the flexible drive shaft. Disengaging the clutch stops the power transfer, but allows the lawn mower engine to continue turning. The invention provides power take-off for several pieces of lawn care equipment including weed trimmers, hedge trimmers, edgers, chainsaws, and blowers. These accessories are attached to the flexible drive shaft cable through a variety of connectors including a four-point star connector.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention is directed to lawn care and lawn maintenance equipment generally, and more specifically to lawn mowers with the capability to power accessory lawn maintenance tools. 
       BACKGROUND OF THE INVENTION 
       [0002]    Lawn care and maintenance equipment of various types, such as lawn mowers, edgers, trimmers, blowers, etc., are used to perform a variety of tasks. Generally, many of these devices include self-contained power sources such as an engine or a motor powered by various fuels, electricity, or batteries. These power sources add an additional cost to each piece of equipment and require the use of additional materials, labor and expenses for construction, use and maintenance. For example, many of these engines require oil, other chemical lubricants, and routine maintenance. Use of such materials also creates disposal and waste problems. 
         [0003]    One type of such lawn care and maintenance equipment is self-powered lawn mowers including riding mowers and walking mowers. Such mowers are generally equipped with a self-contained power source, typically rotary engines or motors with a cutting blade attached to a shaft of the engine. The engine shaft of these mowers rotates to drive the blade for cutting or mulching grass and other lawn coverings. 
         [0004]    Lawns are typically manicured by first trimming grass around trees or fences with a weed trimmer and then riding or pushing a lawn mower to cut the remainder of the grass. Conventional lawn mowers have limited maneuverability such that use of a separate trimming apparatus to cut all of the grass or weeds close to obstacles cannot be avoided. 
         [0005]    Therefore, it is desirable to have lawn care accessories (e.g. edgers, trimmers, etc.) to be attached and powered by lawn mowers to save time and costs in lawn maintenance and power consumption. Furthermore, it is desirable to have the ability to attach lawn equipment to a lawn mower to compensate for the mower&#39;s lack of maneuverability. 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    The invention provides a power take-off from a lawn mower, through a flexible drive shaft cable, to utilize lawn maintenance accessories. The power take-off allows the accessories (e.g. edgers and trimmers) to draw power from the lawn mower&#39;s engine. Flexible drive shafts provide rotary power transmission along curved, non-linear axes. The user can engage or disengage the accessory through use of an electrical or mechanical clutch. The clutch connects the lawn mower engine drive shaft to the flexible drive shaft so that they can either be locked together and spun at the same speed, or decoupled and spun at different speeds. Engaging the clutch transfers power from the lawn mower engine to the flexible drive shaft. Disengaging the clutch stops the power transfer, but allows the lawn mower engine to continue turning. The invention provides power take-off for several pieces of lawn care equipment including weed trimmers, hedge trimmers, edgers, chainsaws, and blowers. These accessories are attached to the flexible drive shaft cable through a variety of connectors including a four-point star connector. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
         [0007]      FIG. 1  is drawing of a lawn mower connected to a lawn maintenance tool through its power take-off and flexible drive shaft. 
           [0008]      FIG. 2  is a detailed drawing of the interior of the lawn mower. 
           [0009]      FIGS. 3   a  and  3   b  are detailed drawings of the lawn mower, the flexible drive shaft, and the connector between the flexible drive shaft and the lawn maintenance tool. 
           [0010]      FIG. 4  is a detailed drawing of an Edger, a lawn maintenance tool. 
           [0011]      FIGS. 5   a  and  5   b  are detailed drawings of a Blower, a lawn maintenance tool. 
           [0012]      FIGS. 6   a  and  6   b  are detailed drawings of a Hedge Trimmer, a lawn maintenance tool. 
           [0013]      FIG. 7  is a detailed drawing of a Chainsaw, a lawn maintenance tool. 
           [0014]      FIGS. 8   a  and  8   b  are detailed drawings of a Weed Trimmer, a lawn maintenance tool. 
           [0015]      FIG. 9  is a detailed drawing of an Electric Clutch. 
           [0016]      FIG. 10  is a drawing of a lawn mower with two power take-offs connected to two lawn maintenance tools, each connected to a power take-off and flexible drive shaft. 
           [0017]      FIG. 11  is a detailed drawing of the interior of the lawn mower containing two power take-offs. 
           [0018]      FIG. 12  is a detailed drawing of the interior of the lawn mower using a gear system to drive the power-take-off and the flexible drive shaft. 
           [0019]      FIG. 13  is a detailed drawing of the interior of the lawn mower using a gear system to drive a power-take-off and flexible drive shaft that is accessible from the side of the lawn mower. 
           [0020]      FIG. 14  is a drawing of a riding lawn mower connected to a lawn maintenance tool through its power take-off and flexible drive shaft. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0021]    Referring now to the figures,  FIG. 1  is a drawing of a lawn mower  5  connected to an Edger  25 , an accessory lawn maintenance tool, through its power take-off (PTO)  10  and flexible drive shaft  15 , The lawn mower shown is a typical rotary lawn mower having a main frame with four wheels that allow it to be pushed or driven across a lawn. The engine  30  of the lawn mower  5  drives power to the Edger  25  through the power take-off  10 , flexible drive shaft  15 , and finally to the power cable  20  of the Edger. 
         [0022]      FIG. 2  is a detailed drawing of the interior of the lawn mower  5 . First, the engine  30  drives the engine drive shaft  70 , which in turn drives the lawn mower blade  80 . Note, the engine can be a 4-stroke gas powered engine with horsepower ranging from 4 hp to 7 hp. However, the present invention can also support a 2-stroke gas powered engine as well as an electric motor with drive shaft powering the mower blade. The engine or electric motor provides a speed of 1 mph to 3.5 mph for the mower. In conventional lawn mower internal combustible engines, the drive shaft  70  has a bottom end extending downward beneath the frame to the blade and a top end is connected to the starter mechanism. Furthermore, the lawn mower must be regularly maintained so that oil sufficiently lubricates its engine. 
         [0023]    The drive pulley system  40  transfers power from the engine drive shaft  70  to the flexible drive shaft  35 . An endless belt  45  (that is connected  73  to the engine drive shaft  70 ), transfers power from the engine drive shaft  70  to the double pulley system  40 . The present invention supports many types of belts including premium, heavy duty Kevlar, and regular types of belts. Specifically, the endless belt  45  transfers power from the engine drive shaft  70  to the coupling pulleys ( 50 ,  52 ) of the double pulley system  40 . The coupling pulleys ( 50 ,  52 ) are held in place by a support shaft  57 . Next, the coupling pulleys ( 50 ,  52 ) drive another endless belt  55  to transfer power to the drive pulley  60 . Finally, the drive pulley  60  transfers power to a drive shaft  65  and finally to the power take-off  10  and the flexible drive shaft  35 . The present invention supports both V-Belt and Flat Belt pulleys. 
         [0024]    In addition,  FIG. 2  shows that the flexible drive shaft  35  is contained within the flexible drive shaft cable  15 . The present invention supports flexible drive shafts made of carbon steel, stainless steel, tempered steel, music wire, rocket wire, bronze alloys, copper alloys, or other similar materials. The flexible cabling can be made from plastic, vinyl, or other similar materials. These materials not only describe the flexible drive shaft  35  and its cable  15  from the PTO  10  but also the flexible drive shafts and cablings for the lawn care accessories. Note, wheels of the lawn mower are also depicted in  FIG. 2  ( 85   a ,  85   b ). 
         [0025]      FIGS. 3   a  and  3   b  are detailed drawings of the lawn mower  5  and the connector  100  between the flexible drive shaft  35  and the Edger  25  lawn maintenance tool. In  FIG. 3   a , the flexible drive shaft cable  15  is a flexible four-point star cable  90  that attaches to a connector  100 . Similarly, the Edger power cable  20  is also a four-point star cable  95  and attaches to the connector  100 . In  FIG. 3   b , the front view of the connector  100  reveals a four point star interface  105  for both the flexible drive shaft cable  35  and Edger power cable  20  to attach. However, the present invention can support any type of connector between the flexible drive shaft cable  35  and any lawn care accessory power cable  20  and any type flexible drive shaft cable  35 . 
         [0026]      FIG. 4  is a detailed drawing of an Edger  25 , a lawn maintenance tool. The Edger  25  along with every lawn care accessory attached to the PTO, has simple cost effective interior mechanics. The PTO eliminates the need for the lawn care accessory to have its own engine or power source. In  FIG. 4 , the Edger power cable  20  contains the Edger flexible drive shaft  112 . This attaches to the Edger power connector  117 . A bearing  110  is attached to the Edger power connector from the inside of the Edger  25 . The bearing can be any roller bearing such as a ball bearing. The Edger flexible drive shaft  112  turns the Edger drive shaft  115 , which turns a first gear  120 . This first gear  120  transfers power to a second gear  125  perpendicular to the first gear  120 . This second gear then powers a drive shaft  140 . The first and second gears ( 120 , 125 ), as well as any gear of the lawn mower or lawn care accessories, can be of any type including bevel, angular, bevel, and crown gears. Finally, the drive shaft  140  turns the Edger&#39;s blade  145 . 
         [0027]      FIGS. 5   a  and  5   b  are detailed drawings of a Blower  151 , a lawn maintenance tool. In  FIG. 5   a , the Blower power cable  150  contains the Blower flexible drive shaft  152 . The Blower power cable  150  attaches to the power connector  154 . The Blower flexible drive shaft  152  turns the drive shaft  157 . Next, the drive shaft  157  turns the first gear  155 , which in turn transfers power to the second gear  170  that is perpendicular to it. The second gear  170  turns the drive shaft  165  that drives the Blower Mechanism  160 .  FIG. 5   b  is a detailed front view drawing of the Blower  151 . It illustrates details of the Blower Mechanism  160 . 
         [0028]      FIGS. 6   a  and  6   b  are detailed drawings of a Hedge Trimmer  176 , a lawn maintenance tool. In  FIG. 6   a , the power cable  175  contains the flexible drive shaft  177 . The power cable  175  attaches to the power connector  179 . The flexible drive shaft  177  turns the first gear  180 , which in turn transfers power to the second gear  190  (perpendicular to the first gear  180 ). The second gear  190  powers the Hedge Trimmer Drive Mechanism  195 . Finally, the Drive Mechanism powers the Hedge Trimmer blade  200 . In addition, there are two bearings ( 185   a ,  185   b ) on either side of the Drive Mechanism  195 .  FIG. 6   b  shows the Side View of the Hedge Trimmer  176 . 
         [0029]      FIG. 7  is a detailed drawing of a Chainsaw  206 , a lawn maintenance tool. In  FIG. 7 , the Chainsaw power cable  205  contains a flexible drive shaft  207 . The power cable attaches to the power connector  209 . There is a bearing  210  inside the Chainsaw  206 , attached to the connector. The flexible drive shaft  207  turns the drive shaft  212  of the Chainsaw  206 . The drive shaft  212  turns the pinion  215 . The pinion  215  transfers power to the power gear  220 . Finally, the power gear, through the drive shaft  222 , runs the Chainsaw blade  225 . 
         [0030]      FIGS. 8   a  and  8   b  are detailed drawings of a Weed Trimmer  231 , a lawn maintenance tool.  FIG. 8   a  shows a Weed Trimmer  231  with power cable  230  and blades ( 235   a ,  235   b ).  FIG. 8   b  is a detailed side view drawing of the Weed Trimmer  231 . The power cable  230  contains a flexible drive shaft  232 . First, the power cable  230  attaches to the power connector  234 . Next, the power cable&#39;s flexible drive shaft  232  turns the flexible drive shaft  240  within the Weed Trimmer  231 . Finally, the flexible drive shaft  240  powers the Blade Mechanism  245  to rotate the blades ( 235   a ,  235   b ). 
         [0031]      FIG. 9  is a detailed drawing of the electric clutch. The clutch that controls the power take-off  10  is engaged by a toggle switch  260  near the lawn mower handle. A cable  255  runs from the toggle switch  260  to the electric clutch  250  attached to the coupling pulleys ( 50 ,  52 ). Toggling the switch  260  in one direction engages the clutch and allows the flexible drive shaft cable  15  to run lawn maintenance accessories. Toggling the switch  260  in the opposite direction disengages the clutch and shuts down the power take-off  10 . 
         [0032]      FIG. 10  is drawing of a lawn mower  5  with two power take-offs ( 10 ,  265 ) connected to two lawn maintenance tools ( 25 ,  231 ) each connected to a power take-off ( 10 ,  265 ) and flexible drive shaft ( 15 ,  270 ). A need may occur in maintaining large grounds, such as parks or golf courses, where it would be necessary to utilize two accessory lawn tools from one lawn mower. For example, one person may use an Edger while another person uses a trimmer. The ability to implement two lawn care tools simultaneously reduces time and cost, and increases efficiency in the work of groundskeepers caring for large lawns (i.e. parks and golf courses). Similar to  FIG. 1 ,  FIG. 10  shows an Edger  25  attached to a PTO  10  through the flexible drive shaft cable  15  and the Edger power cable  20 . However, in addition, there is a second PTO  265  located on the lawn mower  5 . This second PTO  265  is connected to a Weed Trimmer  231  through a second flexible drive shaft cable  270  and the Weed Trimmer power cable  230 . 
         [0033]      FIG. 11  is a detailed drawing of the interior of the lawn mower containing two power take-offs ( 10 ,  265 ). The double pulley systems ( 40 ,  275 ) for both power take-offs ( 10 ,  265 ) mirror each other. The first double pulley system  40  is similar to the one pictured in  FIG. 2 . The second pulley system  275  has an endless belt  285  that transfers power from the engine drive shaft  70  to the coupling pulleys ( 290 ,  295 ) of the second pulley system  275 . The endless belt  285  is attached to the engine drive shaft  70  by a connector  280 . The coupling pulleys ( 290 ,  295 ) are held in place by a support shaft  292 . Another endless belt  300  transfers power from the coupling pulleys ( 290 ,  295 ) to the drive pulley  305 . Next, the drive pulley  305  turns a drive shaft  310 . Finally, the drive shaft  310  powers the second power take-off  265  and its flexible drive shaft  315 . 
         [0034]    The double pulley system  40  can be replaced by a gear system. As is well known in the art, pulleys operate in the same direction as each other when connected through a belt. However, gears operate in the opposite direction of each other. Replacing the double pulley system  40  with a gear system provides the present invention the ability to have the flexible drive shaft  35  and engine drive shaft  70  rotate in opposite directions. Furthermore, a gear system can allow the flexible drive shaft  35  to rotate faster or slower than the engine drive shaft  70 . 
         [0035]      FIG. 12  is a detailed drawing of the interior of the lawn mower using a gear system to drive the power-take-off  10  and the flexible drive shaft  35 . In this embodiment of the present invention, the double pulley system pictured in  FIGS. 2 and 11  is replaced by a gear system  320 . The gear system  320  provides more features to the PTO  10  and flexible drive shaft  35 , but at a higher cost than the double pulley system  40 . In this embodiment, the engine drive shaft  70  turns the first gear  350 . This first gear then powers one of three gears ( 330 ,  335 ,  340 ) as selected by the lawn mower operator. The lawn mower operator can select any one of the three gears by moving the gear selector  355  vertically up and down. The gear selector is similar to a mechanical clutch. As the operator shifts the gear selector up and down, she can choose different gears to run the flexible drive shaft  35  at different speeds. For example in this embodiment, an operator can shift the gear selector to its highest position and choose the top gear  330 . The top gear  330  being the largest gear results in rotating the flexible drive shaft  35  at the slowest speed. The top gear  330  gear selector will drive the top gear  325  of the flexible drive shaft ( 65 ,  35 ). Alternatively, an operator shifting the gear selector  355  down to the middle position can choose the middle gear  335 . This gear is smaller than the top gear  330  resulting in rotating the flexible drive shaft  35  at a higher speed. The middle gear  335  of the gear selector engages the middle gear of the flexible drive shaft ( 65 ,  35 ). Finally, the operator may shift the gear selector to its lowest position and choose the bottom and smallest gear  340 . This gear will drive the flexible drive shaft  35  fastest. The bottom  340  gear of gear selector engages the bottom gear of the flexible drive shaft ( 65 ,  35 ). Once the operator selects one of the shifting gears ( 330 ,  335 , and  340 ) then it transfer power to one of the flexible drive shaft gears ( 325 ,  327 , and  329 ). Subsequently, one of these gears ( 325 ,  327 , and  329 ) powers the flexible drive shaft  35  for the PTO  10 . 
         [0036]      FIG. 13  is a detailed drawing of the interior of the lawn mower using a gear system  375  to drive a power-take-off and flexible drive shaft that is accessible from the side of the lawn mower. In this embodiment of the invention, the gear system  375  provides access to the PTO  370  and flexible drive shaft  35  from the side of the lawn mower. First, the engine drive shaft  70  turns the first gear  350 . Next, the first gear  350  powers the second gear  365  aligned perpendicular to the first gear  350 . Finally, the second gear  365  powers the drive shaft  360  which in turn powers the flexible drive shaft  35  from the side accessible PTO  370 . 
         [0037]      FIG. 14  is a drawing of a riding lawn mower connected to a lawn maintenance tool through its power take-off and flexible drive shaft. This embodiment of the present invention is similar to the embodiment depicted in  FIG. 1 . However, in this embodiment the power take-off  10  and flexible drive shaft cable  15  are attached to a riding lawn mower  400 . In all other aspects this embodiments is similar to the embodiments pictured and described in  FIGS. 1-13 . 
         [0038]    All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. 
         [0039]    The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. 
         [0040]    Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.