Abstract:
A vibratory device ( 10 ) for dispersing a topdressing and correcting the grain in greens. A deck ( 30 ) is supported by a frame ( 18 ) with a linkage ( 36 ) for raising and lowering the deck ( 30 ) with rest to the green. A shaker tray ( 76 ) is vibrated within the deck ( 30 ) by a vibrator ( 108 ) attached to the deck ( 30 ). A brush frame ( 94 ) is carried within the shaker tray ( 76 ) for vibrating against the tips of the grass blades in the green to shake the topdressing into the thatch and to straighten the grass blades. The linkage ( 36 ) to raise and lower the deck permits height adjustment of the brush frame ( 94 ) with respect to the grass blades so that the brush bristles ( 106 ) just tickle the tips minimizing injury to the grass.

Description:
This application claims priority from provisional patent application Ser. No. 60/119,449, filed Feb. 10, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a device for dispersing a topdressing in greens and correcting the grain, while minimizing injury to the grass blades. 
     2. Brief Description of the Prior Art 
     In order to promote vigorous growth necessary to maintain a healthy putting green, groundskeepers periodically aerate the turf. Aeration is accomplished by pulling small dirt plugs out of the green with a spike or core aerator. The plugs are cleared away and sand, a sand/peat mixture or some other topdressing is then applied to the putting surface and brushed, swept, or otherwise worked into the holes. 
     Today, the maintenance program at many golf courses includes topdressing greens at other times during the season. Topdressing may be applied during reconstruction and renovation of older greens and during grow-in of new greens. Frequent topdressings are also applied to established greens to firm the putting surface, improving consistency among the greens. Timely applications of topdressing also help to prevent an undesirable accumulation of thatch in the root zone. A light/frequent topdressing can be used to build a more desirable, sandy growing medium above a native soil profile in existing greens. 
     A topdressing can be worked into the green by hand with a broom, rake or other similar tool. Incorporating topdressing manually is difficult and labor-intensive. Various prior art devices have been proposed to mechanize the process. Most of these devices, however, tend to brush the sand forward with little or no lateral motion, which can leave ridges and a pile of sand on the collar of the green. 
     Because the previously known devices move topdressing primarily in the direction of machine travel, it is often necessary to make multiple passes in order to sufficiently incorporate the top dressing. Making multiple passes causes soil compaction, negating the benefits provided by aeration. In addition, dragging brushes linearly over the turf can align the grass in one direction. This set or grain, can cause golf balls to roll differently in one direction as compared to another and increases the tendency of the turf to mat down. Matted turf is disease-prone and is difficult to mow evenly. 
     There are devices for dispersing topdressings with rotating or reciprocating brushes, but like the devices which move linearly, they tend to bruise the grass blades as the brushes scrub the sand across the green. In addition, the devices with rotating brushes tend to leave a swirly grain in the grass. 
     Topdressings are preferably applied dry to a relatively dry green as the sand tends to stick to the grass when the topdressing is moist or the grass is wet or dew-covered. Humid or rainy weather also complicates the process. While groundskeepers prefer to apply a dry topdressing to a relatively dry green, this practice interferes with the use of the facility and may not be possible on some busy courses. 
     Prior art devices for dispersing topdressings are not very effective when the topdressing or grass is slightly wet. Whether the brush is dragged linearly, reciprocated or rotated, the sand tends to stick on the blades as opposed to falling into the thatch. In addition to injuring the grass blades as the sand is worked across the surface, the sand stuck on the grass blades dulls reels and bedknives when the green is mowed. The sand also interferes with the golfers&#39; enjoyment of the course until the sand is worked into the green. 
     Although there are many problems with topdressing greens, the practice is increasing as the long-term effects of topdressing are positive. What is needed is new equipment that addresses the problems discussed above. 
     BRIEF SUMMARY OF THE INVENTION 
     In view of the above, it is an object of the present invention to provide a device for dispersing a topdressing in a manner that causes the sand to settle into the thatch with less bruising of the grass blades. It is another object to provide a device that corrects the grain of the green as it disperses the topdressing. It is also an object to provide a device that is more effective than existing equipment at dispersing a topdressing when the grass is slightly damp, the topdressing moist, the weather humid, etc. 
     In accordance with the invention, a vibratory device for attachment to a tow vehicle for dispersing a topdressing and correcting the grain in greens, in major part includes: a frame, a deck and a shaker tray with a brush. More particularly, the frame has a top side and a bottom side and is mounted on legs such that the bottom side is elevated above the green. Each leg is mounted on a rotary member for rolling the frame across the green. 
     The deck has a top side and a bottom side with side rails. The top side of the deck is attached to the bottom side of the frame. The shaker tray has a top side and a bottom side and is adapted to be reciprocated between the side rails of the deck. A vibrator is mounted on the deck and attached to the top side of the shaker tray. The brush has a plurality of bristles and is mounted on the bottom side of the shaker tray. The bristles-disperse the topdressing in the green when vibrated against the grass blades. 
     The invention summarized above comprises the constructions hereinafter described, the scope of the invention being indicated by the subjoined claims. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     In the accompanying drawings, in which several of various possible embodiments of the invention are illustrated, corresponding reference characters refer to corresponding parts throughout the several views of the drawings in which: 
     FIG. 1 is a perspective view of a vibratory device for dispersing a topdressing and correcting the grain in golf greens in accordance with the present invention; 
     FIG. 1A is a perspective view of the vibratory device shown in FIG. 1 adapted to be towed by a another type of tow vehicle; 
     FIG. 2 is a plan view of the vibratory device; 
     FIG. 3 is a right side elevation of the vibratory device; 
     FIG. 4 is a sectional view taken along line  4 — 4  in FIG. 3; 
     FIG. 5 is a sectional view taken along line  5 — 5  in FIG. 4; 
     FIG. 6 is a sectional view taken along line  6 — 6  in FIG. 4; 
     FIG. 7 is a plan view of the vibratory device with portions of a deck broken away to show details of a shaker tray and a vibrator to vibrate the tray; 
     FIG. 8 is a sectional view taken along line  8 — 8  in FIG. 7; 
     FIG. 9 is a sectional view taken along line  9 — 9  in FIG. 5; 
     FIG. 10 is a side elevation taken along line  10 — 10  in FIG. 9; 
     FIG. 11 is a detail, in cross-section, on an enlarged scale and taken along line  11 — 11  in FIG. 7 to show details of the vibrator for the tray; 
     FIG. 12 is a perspective bottom view of a brush frame that is carried by the shaker tray and vibrated against the tips of the grass blades; 
     FIG. 13 is a detail, in cross-section, on an enlarged scale and taken along line  13 — 13  in FIG. 5 to show a handle for raising and lowering the deck with a pointer; and, 
     FIG. 14 is a detail, in cross-section, on an enlarged scale and taken along line  14 — 14  in FIG.  7 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings more particularly by reference character, reference numeral  10  refers to a vibratory device in accordance with the present invention. In FIG. 1, device  10  is viewed from the rear, as it would be seen by an operator seated on a triplex mower or the like, to which it is adapted to be attached. In the form illustrated in the drawings, device  10  is adapted to be towed by a triplex mower of a type having a lift bar and a pull frame. For this purpose a hook  12  mounted on a plate  14  and a pair of tow brackets  1   6  are provided for attachment of device  10  to the mower after the reel cutting units have been removed. It will be understood, however, that device  10  may be easily adapted for attachment to other tow vehicles as shown in FIG.  1 A. For example, tow brackets  16  and hook  12  may be removed and plate  14  replaced with another plate  14  having a lift pin  15  and an L-shaped bracket  17 , depending on the mower (e.g., Jacobsen versus Toro and so forth). Hence, it will be apparent that the exact nature of the attachment depends upon the construction details of the tow vehicle, which, in addition to triplex mowers, may include other vehicles such as a utility tractor. 
     Frame 
     Device  10  has a frame  18  with a top side  20  and a bottom side  22 . Frame  18  is mounted on legs  24  such that the bottom side  22  is elevated above the green. Each of legs  24  is mounted on a rotary member  26 , such as a roller, for rolling the frame across the green. In the form illustrated in the drawings, frame  18  is a flat, triangular plate with depending side walls forming a skirt  28  around bottom side  22  and with three legs  24  mounted near the vertices. The lower part of legs  24  is preferably U-shaped in cross-section with a roller pinned between the arms thereof. While frame  18  is preferably triangular in shape, it may be rectangular or of any suitable configuration, what is important is that device  10  have three-point suspension so that it floats over any uneven contours of the green. 
     Deck 
     A deck  30  is mounted under frame  18 , preferably such that it can be raised and lowered with respect to the green. Deck  30  has a top side  32  and a bottom side  34  and is attached to the bottom side  22  of frame  18  with a linkage  36  to raise and lower the deck with respect to the green. A motor mounting plate  38  (FIG. 3) is attached to one end of deck  30  adjacent a cutout  40  (best seen in FIGS. 2 and 4) for use as described below. Deck  30  is generally rectangular with a pair of depending side rails  42  and one end wall  43 . Side rails  42  and end wall  43  may be provided as an integral skirt and deck  30  is preferably symmetrical about its longitudinal axis such that it may be reversed right to left in frame  18  so that motor mounting plate  38  is positioned on the left instead of the right when required for adaption to the construction details of the tow vehicle. Attached to side rails  42 , at opposite ends thereof, are roller guides  44  (FIG. 8) for use as described below. Each roller guide  44  is formed by a pair of spaced apart blocks  46  attached on the inside of side rails  42  and joined together on the bottom with a retainer plate  48 . A nylon glide  50  lines the cavity formed by blocks  46  and retainer plate  48 . 
     Linkage for Raising and Lowering the Deck 
     As shown in FIGS. 4-6, linkage  36  for raising and lowering the deck includes a shaft  52  which is journaled in frame  18  with a first end extending through skirt  28  at the front of device  10  for attachment to a handle  54  and a second end at the rear for attachment of a threaded clamp-on collar  55 . Opposite ends of shaft  52  are threaded with threads  56  of opposite hand for engagement of traveling nuts  58 ,  60  and for engagement of handle  54  and clamp-on collar  55 . The threads of traveling nuts  58 ,  60  are of the same hand as the threads on shaft  52  such that when shaft  52  is rotated with handle  54 , traveling nuts  58 ,  60  move towards and away from each other while clamp-on collar  55  restrains shaft  52  from longitudinal movement. For this to occur, traveling nuts  58 ,  60  must be restrained from rotating with shaft  52 . The center of an L-shaped link  62  is loosely pivoted to nut  58  at the rear of device  10 , with one end attached to a rod  64  and the opposite end pivoted to a mounting block  66 . Rod  64  is rotated by L-shaped link  62  and is journaled in rear leg  24 . A straight link  68  is loosely pivoted to nut  60  at the front of device  10 , with the opposite end of the link attached to a rod  70  so that rod  70  rotates with link  68 . Opposite ends of rod  70  are pivoted between a pair of blocks  72  attached to skirt  28 . A pair of mounting arms  74  are attached to opposite ends of rod  70  at the front of device  10 . The other end of each mounting arm  74  is pivoted to two additional mounting blocks  66 . Mounting blocks  66  at the front and rear of frame  18  are attached to top side  32  of deck  30 . Replaceable nylon bearings  75  are preferably provided in each of mounting blocks  66  and  72  (see FIG.  4 ). L-shaped link  62  and straight link  68  keep nuts  58 ,  60  from rotating on shaft  52 . By twisting handle  54 , shaft  52  and traveling nuts  58 ,  60  cause deck  30  to be raised and lowered on mounting blocks  66  with respect to the green. A coil spring  77  may be provided to keep backlash out of linkage  36 , with spring  77  connected to links  79 ,  81 . Links  79 ,  81  are welded or the like to rods  64 ,  70 , respectively. 
     As best seen in FIG. 13, handle  54  may be coupled to a dial plate  83  also attached to shaft  52 . Dial plate  83  may include a plurality of dimples  85  facing the outside of skirt  28  for cooperative receipt of a spring biased ball plunger  87 . Plunger  87  keeps handle  54  and shaft  52  from accidentally rotating and changing the level of deck  30  with respect to the green. With continuing reference to FIG. 13, as best seen therein, a pointer  89  is attached to traveling nut  60 . Pointer  89  extends through a slot  91  provided in top side  20  of frame  18  and references a gage plate  93 . Markings on gage plate  93  may be provided such that the distance between adjacent markings correlates with one full rotation of handle  54 , or otherwise, for use in positioning deck  30  at some predetermined level. 
     Shaker Tray 
     As shown in FIGS. 7-10, a shaker tray  76  with a top side  78  and a bottom side  80  is adapted to be reciprocated between side rails  42  of deck  30 . For this purpose, it is preferred that shaker tray  76  be mounted on carriers such as rollers  82  between the side rails  42  of deck  30 . Rollers  82  are received in roller guides  44  and ride on nylon glides  50 . Shaker tray  76 , like deck  30  is generally rectangular and has side rails  84 . Side rails  84  have inwardly directly toes  86 , forming a slot  88  between bottom side  80  and side rails  84  for use as described below. As shown in the drawings, the base of shaker tray  76  is U-shaped in cross section and side rails  84  are L-shaped and attached to the sidewalls of the shaker tray base. An end wall  95  interconnects side rails  84  and a transverse reinforcing strap  90  may be attached to top side  78  near one end of the tray. A bolt  92 , for use as described below, is passed from bottom side  80  to top side  78  through a hole provided in strap  90  and the base of shaker tray  76 . 
     Brush Frame 
     A brush frame  94  (seen in FIGS. 1,  3  and  12 ) is received in slot  88 , one end of which is closed by wall  95 , while the other end of which is blocked with clips  96  attached to blocks  98  (FIG. 10) provided on top side  78  of shaker tray  76 . Brush frame  94  (FIG. 12) has a headboard  100  with a top side  102  and a bottom side  104 . A plurality of bristles  106  are arranged in rows on bottom side  104  of headboard  100 . The rows are preferably batwing in shape and extend substantially across headboard  100 . As shown in FIG. 12, the number of bristles at the ends of the rows is the same as in the middle. With a V-shape, as compared to a batwing configuration, there are fewer bristles at the ends of the “V” so that the brush wears on the ends and does not disperse the topdressing as well. The batwing configuration overcomes this problem and is more efficient than a straight brush at moving the sand into the aeration holes. It is preferred that different brush frames  94  be provided with bristles  106  of different diameter. For example, a brush frame  94  with bristles having a diameter of 0.0015 inch may be provided for use in grain correction, whereas a brush frame with bristles having a diameter of 0.0030 or 0.0045 inch provide more aggressive action and may be used for knocking wet sand off the grass blades. It should be understood that these examples are set forth by way of illustration, not limitation. 
     Vibrator for the Shaker Tray 
     A vibrator  108  is attached to deck  30  and top side  78  of shaker tray  76  to vibrate the shaker tray in the deck. As best seen in FIGS. 7 and 11, vibrator  108  may include a wobble plate  110  mounted at an angle on a shaft  112  and rotated by a rotary motor (not shown) attached to motor mounting plate  38 . As defined herein, the rotary motor includes any source of mechanical rotating power including a hydraulic motor, a hydrostatic motor, a gasoline engine, an electric motor, a power take-off connection or the like. Rotary motor has a horizontal output shaft that is connected to stub shaft  112  journaled within a bearing  114  in a base  116  attached to motor mounting plate  38 . Bearing  114  is preferably a double row bearing, as shown in FIG. 11. A free end of stub shaft  112  is cut at an angle between about 2 and 10 degrees, preferably between about 3 and 7 degrees and is tapped for receipt of a bolt  118 . 
     With continuing reference to FIG. 11, bolt  118  attaches wobble plate  110  to stub shaft  112 . Wobble plate  110  includes a wobble ring  120  into which is press fit a bearing  122 . Bearing  122  is retained within wobble ring  120  by an attachment plate  124  which is joined to wobble ring  120  with bolt  118 . Bearing  122 , like bearing  114 , is preferably a double row bearing, as shown in FIG. 11. A flat  126  is formed on wobble plate  110  and tapped for receipt of a bolt  128  for attachment of a linkage  130  for connecting wobble plate  110  to shaker tray  76 . Linkage  130  passes through cutout  40  in deck  30 . When bolt  128  in wobble ring  120  is 1½ inches from the center of stub shaft  112 , wobble plate  110  will vibrate about ¼ inch in a plane parallel to the long axis of shaker tray  76 . As stub shaft  112  rotates in bearing  114 , wobble plate  110  also rocks from side to side, which motion results in a misalignment of linkage  130  connecting bolt  92  in shaker tray  76  with bolt  128  in wobble ring  120 . This misalignment can be compensated for when linkage  130  is outfitted with spherical rod ends  132 . A pair of cushioning blocks  133  may be provided on shaker tray  76 , flanking linkage  130  to keep the linkage from swinging from left to right. Each cushioning block  133  may be made from a stick of hard rubber or other suitable elastomeric material extending out of a block. One or more springs  134 , each of which housed in a hollow boss  135  on the inside of end wall  43  of deck  30  (see FIGS.  7  and  14 ), take the pressure off spherical rod ends  132 , by pushing against end wall  95  of shaker tray  76  as an assist on the return stroke. Other suitable linkages  130 , as will occur those skilled in the art, may be used to compensate for the aforementioned misalignment. 
     Use 
     Before vibratory device  10  is used, a topdressing is applied to a green with a sand distributor or spreader. A large amount of topdressing may be applied after aeration to fill the holes left by the aeration process. Throughout the season, smaller amounts of topdressing, sometimes just a dusting, may be applied as frequently as once a week to control the thatch and to make the greens faster. In all instances, vibratory device  10  disperses the topdressing into the thatch with much less damage to the blades of grass than was possible before. 
     With prior art devices for dispersing the topdressing, the sand is bulldozed across the green and ground into the grass with brushes that either drag or scrub. As the topdressing is dispersed, the sand bruises the blades of grass, which are made more susceptible to disease or burning. When a down pressure is applied, the prior art devices may even dig sand out of the thatch. 
     Hydraulic motors driven off a triplex mower typically operate at 2,000 rpm. When the rotary motor used with device  10  is such a motor, shaker tray  76  makes 2,000 vibrations per minute. By using handle  54  for raising and lowering deck  30  with respect to the green, it is possible to operate device  10  such that bristles  106  just tickle the tips of the grass blades and the vibrations cause the sand to fall into the thatch. An additional benefit is that as device  10  disperses the topdressing, it also corrects the grain as bristles  106  leave the grass blades in an upright position. 
     By using the height adjustment, device  10  may be operated in such a manner that the topdressing is not dragged or scrubbed through the green. The grass blades are less bruised and the sand is not disturbed in the thatch. Since the sand is shaken off the grass blades, the topdressing does not dull a mower when the green is mowed or interfere with the golfers&#39;enjoyment of the course. Device  10  can be used to disperse topdressing even when the topdressing is somewhat moist or the grass slightly wet. This is particularly important when topdressings are being frequently applied as it is desirable to do the work during the night or in the early morning to avoid interrupting play. 
     In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained. As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.