Abstract:
A system for modifying the surface temperature and/or relative humidity of golf greens or other grass playing fields by applying temperature controlled air and/or a water mist through pop-up nozzles. The nozzles are controlled by a central control panel which activates the nozzles based on input from temperature sensitive probes in the greens.

Description:
FIELD OF THE INVENTION 
     This invention relates to agronomy, in general, and golf course greens keeping, specifically. One of the most important elements of golf course management is the health of the putting greens. In attempting to maintain the most luxurious growth of grass, close attention is paid to watering and feeding of the greens. However, very little has been done in the area of temperature control, other than watering, even though it is well known that each species of greens grass has an optimum temperature range for best results. This invention provides a system by which the surface temperature of the grass may be changed from the ambient temperature without introducing other deleterious agents. 
     BACKGROUND OF THE INVENTION 
     Temperature control, or cooling, of the golf greens has conventionally been a by-product of watering. However, in the hotter climates or in the hotter parts of the summer, temperature control would require too much water for healthy growth of the grass. Too much water, particularly in high humidity conditions, may create a continuous wet environment more favorable to fungi, mildew, or other deleterious agents. Whereas watering during the heat of the day affects the subsoil which damages the root system of the grass. Therefore, watering, alone, can not be used to control temperature for a sustained period of time. 
     Large fans, located adjacent the greens, have been employed to control humidity and temperature by moving the air across the green. Any cooling effects are directly related to evaporation and in a high relative humidity environment there is little evaporation. In the situation where there is a low humidity heat, there is no water vapor to evaporate. This amounts to a hot dry wind which dries out the subsoil quicker than normal. In addition to the substantial breeze created by the fans, the noise produced is a distraction to the players. 
     The art of greens keeping lacks a system which can be used continuously in all high heat and high or low humidity conditions to control the temperature of the air directly above the green without deleterious side effects. 
     DESCRIPTION OF THE PRIOR ART 
     There are numerous devices for affecting the temperature of golf course greens. U.S. Pat. Nos. 5,596,836; 5,617,670; and 5,636,473 to Benson disclose an underground system for delivering treated air to the subsoil of a green. The operation of these devices depend on the specific preparation of the subsoil for their operation. This includes installation of a gravel bed under the green as part of the site preparation. The treated air is delivered underground and percolates upwardly through the gravel bed and the sod to achieve its desired result. U.S. Pat. No. 5,590,980 to Daniel discloses an underground system of conduits connected to a vacuum pump and reservoir to control the moisture content of the green through drainage. Yoshizaki, U.S. Pat. No. 5,306,317 uses an underground conduit system and a boiler for heating the soil for optimum growth. Rearden et al, U.S. Pat. No. 5,368,092, discloses a subsurface array of tubes for circulating a temperature controlling fluid and a temperature sensor for control of the device. 
     All of these devices attempt to influence the surface temperature of the green from subterranean application of the temperature altering agents. The intervening layers of earth and/or gravel would clearly act as a heat sink and detract from effectiveness of these agents on the upper surface of the grass. 
     SUMMARY OF THE INVENTION 
     A system for modifying the surface temperature and/or relative humidity of golf greens or other grass playing fields by applying temperature controlled air and/or a water mist through pop-up nozzles. The nozzles are controlled by a central control panel which activates the nozzles based on input from temperature sensitive probes in the greens. 
     Accordingly, it is an objective of the instant invention to teach the application of temperature controlling agents directly to the upper surface of the grass. 
     It is a further objective of the instant invention to teach the use of a temperature controlled air flow upon the surface of the grass which may be applied continuously without injury to the grass. 
     It is yet another objective of the instant invention to teach a system of providing temperature controlled air flow through an array of distribution lines which include the temperature and humidity modification of ambient air and delivery to the upper surface of the green. The system may be controlled by temperature sensitive probes inserted in the sod. 
     It is a still further objective of the invention to provide a particular nozzle construction for applying the temperature controlled air flow wherein the nozzle is displaced from an at-rest position within the sod to an activated position above the grass. The displacement of the nozzle may be accomplished by air flow. 
     Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     FIG. 1 is a schematic of the system of this invention; 
     FIG. 2 is a cross section of a nozzle of this invention in the activated position showing louvers for directing air flow; and 
     FIG. 3 is a cross section of a nozzle of this invention in the at-rest position showing the air activation mechanism. 
    
    
     DESCRIPTION OF THE INVENTION 
     The overall view of the system  10 , shown in FIG. 1, includes the features of a golf course. In this instance, a lake is a part of the golf course either as a source of irrigation water or an obstacle for the golfers or both. The deeper water in the lake has a naturally occurring, nearly constant, temperature which is below the ambient air temperature during the growing season. In the embodiment illustrated, the lake is the medium within which the radiator  3  is immersed. Of course, the radiator could be submerged in any fluid medium with a preselected temperature, such as a container of ice water or, in colder climates, a container of warm water. The fluid medium includes gases also, e.g. the radiator could be placed in a cavern or ice house. The temperature of the entrained air within the radiator coil is the result of the heat exchange through the radiator tubing. As shown, the radiator  3  is a rectilinear array of tubing but it can take any form, such as circular, to create a large surface area of tubing for increased heat exchange. 
     Atmospheric air is drawn into the inlet  1  of line  2  and passes through radiator  3  by the operation of the air pump  8 . Once the air has been temperature modified by the radiator, the remainder of the lines in the system are either buried or insulated or both. 
     The pump  8  may be reciprocal or rotary with an inlet line  4  carrying the temperature modified air through the system for distribution to the greens by line  11 . Inlet line  4  has an inlet valve  5  for controlling the inlet air flow. Another air inlet  6  is located on the air pump  8  for entraining air to operate the nozzles  20  through manifold  17 . Line  6  also has an on-off valve  7  for control of ambient air flow. A compressor (not shown) is operatively connected with the nozzles  20  to provide motive force for moving the nozzles from an at-rest position to an activated position. A supply line  29  for pressurized air connects the compressor and the nozzles. The compressor may or may not use preconditioned air. 
     The system may also be connected to the irrigation system  16  of the golf course. The irrigation system has a manifold  15  which connects with the nozzles  20 . The manifold is controlled by the control panel  9  and line  12 . 
     The system is operated through a control panel  9  which includes conventional air pressure gauges; air temperature gauges, both ambient and system; soil temperature gauges, both ambient and system; on/off control switches, both air alone and air and water; sensors, both temperature and humidity; a timer and a computer or CPU (none shown). 
     In a program mode, the sensor probes  14  which are placed in the soil of the greens give a reading of the temperature and humidity conditions existing on each green. In the program mode, air, only ; humidity, only; or both may be selected. If either or both of these conditions exceed a programmed preset limit, for any green, the CPU activates the system to produce temperature modified air flow, with or without humidity modification. The treatment may be a timed period or it may continue until the conditions fall within the preset limits. 
     As shown, in FIG. 1, there may be several probes  14  placed in each green. The CPU may activate the system based on the average of these readings or on the highest or on the lowest. The CPU may be programed to read only the temperature or humidity or the heat index based on both. 
     In a timed mode, the system may activate any combination of greens at a particular time for a particular period for temperature or humidity control or both. 
     As shown in FIG. 1, there is a golfer delay switch  18  located near the golf cart path  19 . This allows the treatment of the greens to be temporarily interrupted during play. The switch  18  includes a timer which may be fixed or adjustable. For example, in the fixed mode, the air and/or water treatment of the green would cease for a short period, such as 5 minutes, the switch is activated, then resume. When the cooler air, alone, is being delivered to the greens, the switch  18  may be deactivated. 
     The nozzle  20  shown in FIG. 2 in the activated position is extended upwardly out of the housing  21  and has open louvers  23  directing the temperature modified air parallel to the ground just above the grass. The louvers are pivotally mounted in the nozzle in such a way that the flow of conditioned air will open the passageway. The nozzle  20  has a bell shaped upper portion  26  carrying the louvers. The bell shaped portion continues into a tubular portion  24  which telescopes into a tubular housing extension in the at-rest position. The tubular portion  24  reciprocates through an annular collar  27  which acts as a guide for the movement. The collar  27  also forms the reaction surface for the return spring  28 . The other end of the return spring  28  is captured by the collar  38  at the lower end of the tubular portion  24 . The compressed return spring  28  expands to return the nozzle to the at-rest position when the system is inactive. The flange  25  surrounding the mouth of the housing is located at ground level and acts as a stop for the downward movement of the nozzle  20 . The lower tubular extremity of the housing  21  has a connection  22  for the conditioned air distribution line  11 . 
     In FIG. 3, the nozzle, in the at-rest position, is broken away to show the other working elements. The return spring  28  is extended and upper portion  26  of the nozzle is in contact with flange  25 . Since no air is circulating, the louvers  23  are closed. The nozzles  20  are activated by high pressure air supplied by line  29  into cylinder  30 . The high pressure air moves the piston  31  and piston rod  32  to raise the upper portion of the nozzle. The piston rod  32  has an attachment  32 ′ connected to a control arm  33  attached to the misting nozzle  34 . 
     The misting nozzle  34  is connected to water line  35 . Inside housing  21  there is an excess  36  of water line  35  to accommodate the movement of the misting nozzle. The pressure in this water line may be adjusted to give a fine spray for humidity control without flooding the green. 
     As shown in FIG. 1, some of the nozzles  13  around a green may not be connected to the irrigation system  16 . 
     In the program mode, the sensors  14  signal the control panel  9  that a green or greens is/are out of parameters of temperature or humidity or both, the control panel signals the air pump  8  and compressor to activate some or all of the nozzles  20  around the affected greens. Temperature adjusted air begins to flow and compressed air is delivered to raise each nozzle. If a humidity parameter is selected, the control panel signals the water system to supply water to each activated nozzle. This activated condition will continue either until the sensors show each green is within parameters or for a preselected period of time. 
     It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement of parts herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification and drawings.