Abstract:
An automated tee device uses air pressure through a tee to determine whether a ball is rested on the tee or whether a next ball should be supplied. When a ball is in a rest position on the tee, the airflow through a passage within the tee is inhibited. Consequently, by determining the current condition of airflow through the tee, it can be determined whether a ball is rested on the tee or whether a next ball should be supplied. In accordance with a second aspect of the invention, the tee can be adjusted to any height within a preselected vertical range. Upper and lower limit switches reverse the adjustment of a tee height in response to determining that the upper or the lower limit of the range has been reached. The automated tee device may be used in sports such as golf, baseball and softball.

Description:
TECHNICAL FIELD  
         [0001]    The invention relates generally to tee devices for practicing a sport, such as golf, and more particularly to technologies for verifying that a ball is placed on a tee device and for allowing the height of the ball to be easily adjusted.  
         BACKGROUND ART  
         [0002]    Tee devices are used in various sports to practice hitting skills. For example, tee devices commonly are used in baseball, softball and golf. Typically, the participant must manually set the ball on the device, but the benefits of a practice sessions are increased if an automated ball supply mechanism is used to replace a ball after each swing.  
           [0003]    Often, a detection system is included within an automated ball supply mechanism to confirm that a ball has been placed on a tee device. In a golf practice device for a driving practice range, a reflecting type of photocell may be used. The photocell emits light to a golf ball placed on a tee and receives reflected light. When the reflected light is detected, a ball-confirmation signal is transmitted to a control device, which causes a ball supply arm to reset so as to draw away from the tee. This stops the next ball from being supplied. If the reflected light is not received within a preselected period of time, the photocell system emits a ball-unconfirmed signal to the control device, which then causes the ball supply arm to draw near the tee and supply the next ball. For tee devices that reside below a floor level, the supply operation may also include moving the tee device upwardly and downwardly relative to the floor level.  
           [0004]    An alternative golf ball confirmation approach is to connect the tee to a weight sensor or a load sensor. When a golf is placed on the tee, the sensor detects the increase in weight. The sensor then transmits a ball-confirmation signal, similar to the photocell approach. Automated supply operations may be identical to the ones described with reference to the use of the photocell.  
           [0005]    While the prior art approaches operate reasonably well for their intended purposes, there are concerns. For example, in a driving range environment, the automated devices are exposed to rain. Moreover, dust accumulates and light may be inadvertently blocked. Another concern is that direct sunlight will reflect off the ball and may lead to false readings by the photocell system. For the weight sensor approach of ball confirmation, malfunctions may occur when the tee is inadvertently touched. Particularly, when a ball is supplied at a level below a floor, there are experiences of malfunctions as a result of age deterioration as the tee is regularly raised and lowered. Resistance from the accumulation of dirt and the like is also a cause of malfunctions. Finally, the weight sensors may be susceptible to false readings as a result of the differences in weights of practice balls and some official balls.  
           [0006]    An object of the invention is to provide a key device for sports practice, where the tee device has an automated system with a low susceptibility to malfunctions and false readings. Another object is to provide a tee device that enables mechanized manipulation of ball height.  
         SUMMARY OF THE INVENTION  
         [0007]    An automated tee device utilizes air pressure to determine when a next ball should be supplied to a ball-seating end of a tee. The tee includes an air passageway to an outlet at the ball-seating end. The air passageway is connected to a supply of pressurized air which has a pressure that is less than the gravitational force of a ball at rest on the ball-seating end of the tee. In one application, the ball-seating end is configured to support a golf ball. A detector monitors airflow through the air passageway and outputs a signal that is indicative of the current condition of airflow. This signal is transmitted to a controller which triggers automated operations on the basis of the current state of the signal.  
           [0008]    The controller may be a central processing unit (CPU) that operates a ball supply mechanism for automatically feeding balls to the ball-seating end of the tee. In some applications, the ball is supplied at a sub-floor level, so that the controller cooperates with the detector to determine when the tee should be lowered to receive the next ball.  
           [0009]    The detector may include a movable member having a rest position and a displaced position. The movable member should be located along the airflow path from the airflow supply to the ball-seating end of the tee. The movable member is forced by airflow from its rest position to its displaced position when there is no ball at rest on the ball-seating end. The detector also includes a sensor which monitors the position of the movable member and outputs a signal on the basis of the current position.  
           [0010]    The movable member may be a butterfly board that is oriented to inhibit airflow when the butterfly board is in its rest position. However, when a ball is removed from the ball-seating end of the tee, airflow forces the butterfly board to the displaced position. An optical sensor may be used to determine the position of the butterfly board.  
           [0011]    As another aspect of the invention, the automated tee device may include a height adjustment system. In accordance with this aspect, the height adjustment system includes a motor connected to the tee to adjust a vertical position of the ball-seating end to any position within a preselected vertical range. An activation switch turns the motor on and off. An upper limit switch is mechanically associated with the tee and electrically associated with the motor to automatically reverse the direction of the motor in response to the ball-seating end reaching an upper vertical limit of the range. Similarly, a lower limit switch is mechanically associated with the tee and electrically associated with the motor to again reverse the direction of the tee adjustment in response to the ball-seating end reaching a lower vertical limit within the range.  
           [0012]    An advantage of the invention is that the air pressure detection provides a reliable indication of the presence or absence of a ball on the tee. The ball may be a golf ball, but can also be a baseball, a softball, or the like. Another advantage of the invention is that the automated tee device is easily maintained, since the sensing capability is housed within the airflow path and is therefore not directly exposed to the environment. Another advantage is that the height of a ball can be readily adjusted to fit the preferences of the users.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a perspective view of a tee device for golf practice in accordance with one embodiment of the invention.  
         [0014]    [0014]FIG. 2 is a perspective view of an airflow detection system for the golf tee device of FIG. 1.  
         [0015]    [0015]FIG. 3 is a schematic diagram of electrical components of the tee device of FIG. 1. 
     
    
     DETAILED DESCRIPTION  
       [0016]    With reference to FIG. 1, a tee device for golf practice is built into a golf practice bay of a driving range. A golf ball  15  is supplied onto a tee  10  when the tee is below a floor  16  having an opening  17 . When the golf ball is loaded onto the tee, the tee rises through the opening in the floor, until the ball reaches a driving position.  
         [0017]    The tee is made of a flexible material, such as a urethane rubber having a highly elastic restoring nature. The tee has a cylindrical shape with a vertical passageway  13  that is exposed on the upper end  11  (i.e., ball-seating end) of the tee. The lower end of the tee is closed with a cap  12 . The tee device also includes an airflow supply portion  20  which is connected to the cap  12  to supply a flow of air through the vertical passageway  13  within the tee  10 .  
         [0018]    A golf ball supply path  30  is used to guide the golf ball  15  to the top of the tee  10 . While not fully shown in FIG. 1, the end  31  of the supply path includes a stop gate which is used to control a position of the golf ball relative to the upper end  11  of the tee. The stop gate may be a mechanical device, or may be an electrical device controlled by a central processing unit (CPU)  50 . The CPU also controls a system  60  for raising and lowering the tee.  
         [0019]    Referring now to FIGS. 1 and 2, an airflow detector  40  is used to monitor airflow within an internal passage  25  of a tube  22  that is part of the airflow supply portion  20 . When there is no golf ball  15  on the upper end  11  of the tee  10 , the airflow detector  40  will detect a flow of air through the tube  22 . On the other hand, when the golf ball  15  is resting on the upper end of the tee, airflow will be inhibited and the appropriate detection signal will be transmitted to the CPU  50 . A mini-blower  21  generates a small pressure airflow to the tube  22 . The airflow passes through a detection box  23  having the detector  40  and proceeds to the vertical passageway  13  through the tee, as indicated by arrow Y 1 . The detection box is a hollow rectangular member that may be formed with the tube as a single piece. A separate mini-blower may be provided for each tee device of a driving range or the driving range may have a single mini-blower that provides a flow that is distributed to the various tee devices of the range. Optionally, an air filter may be provided within the airflow passage portion  20 .  
         [0020]    The airflow detector  40  includes a butterfly board  41  that is mounted to swing in response to the flow of air through the detection box  23 . The butterfly board is shown in a rest position (P 2 ) that indicates a lack of airflow, but FIG. 2 also includes a phantom drawing of the butterfly board in an airflow-presence position (P 1 ). The butterfly board  41  is mounted within the detection box  23  using rods  42 , which define the swing axis of the butterfly board. The board remains in a rest position as a result of its weight, unless air pressure overcomes the weight of the board.  
         [0021]    A small board-shaped protrusion  43  extends from the center of the butterfly board  41 . The protrusion is shown in a light-blocking position relative to an optical sensor unit  45 . In this position, the optical sensor unit will generate an airflow-stoppage detection signal. The optical sensor unit comprises a concave-shaped support platform  46  having a cavity aligned with the swingable board-shaped protrusion  43 . A photocell  47  is positioned at the support platform such that the optical emission portion and the optical receiving portion face each other. Consequently, when the protrusion is positioned as shown in FIG. 2, light passage is blocked.  
         [0022]    The butterfly board  41  is mounted using the rods  42  such that the butterfly board is able to rotate relative to the opposite walls of the airflow detection box. The dimensions of the butterfly board are smaller than the cross sectional dimensions of the interior of the detection box. The concave support platform  46  is removably attached to the bottom floor of the detection box, so that maintenance is easy to implement. While the embodiment is shown as having a transparent type photocell  47 , a reflective type photocell may be positioned directly on a sidewall of the detection box, so that the support platform is not critical to the invention. Moreover, other types of sensors may be adapted in place of the optical sensor. For example, an electrical field sensor, a magnetic sensor, or an ultrasound wave sensor may be used without diverting from the invention. As another possible approach, the detection box  23  may be omitted and a circular butterfly board may be supported to swing inside the tube  22 , with the optical sensing capability also being provided within the tube.  
         [0023]    The golf ball supply path  30  of FIG. 1 may be formed as a means to place golf balls  15  on the tee  10 . The supply path includes a sloping runway from a ball hopper (not shown) which holds numerous golf balls for use in practice. The ball stop gate limits the supply to a single ball at a time. The end  31  of the supply path defines a positioning frame to stably load a golf ball when the tee is in its ball transfer position. When the golf ball  15  is placed at the upper end  11  of the tee, the airflow detector  40  recognizes that the airflow through the detection box  23  has ceased, and an appropriate airflow stoppage detection signal is generated by the photocell  47 . The signal is transmitted to the CPU  50 , which closes the gate that would otherwise supply the next golf ball. It is not until the golf ball has been removed from the upper end  11  of the tee that the next golf ball will be allowed to progress.  
         [0024]    The tee raising and lowering system  60  includes a reversible motor  61  mounted on a sidewall of a bracket  59 . A vertical rack  63  meshes with a pinion gear  62  fixed to an output axis of the reversible motor. When the pinion gear  62  is rotated, the rack is moved upwardly or downwardly, depending upon the direction of rotation of the pinion gear. A vertical slider  64  is fixed to the rack and moves upwardly and downwardly along a stationary guide  65  attached to the bracket  59 . The tee  10  is attached to the slider  64  for movement with the slider. In operation, when a golf ball  15  is placed on the upper end  11  of the tee, the airflow detector  40  detects that the flow of air within the internal passage  25  of the airflow supply portion  20  has stopped. In response, the airflow-stoppage detection signal is generated by the photocell  47  and is transmitted to the CPU  50 . The CPU triggers operation of the reversible motor in order to raise the position of the tee  10 .  
         [0025]    Referring to FIGS. 1 and 3, the CPU causes the motor  61  to run in a forward direction by controlling a relay  68  via a transistor  69 . The golf ball then rises through the opening  17  within the floor  16 , allowing a golfer to drive the ball from the tee  10 . When the golf ball is removed from the tee, airflow again occurs within the detection box  23 , causing the detector  40  to generate an airflow detection signal that is received by the CPU. The CPU triggers backward operation of the motor by activating a second relay  66  via a second transistor  67 . As a result, the tee is lowered to the position shown in FIG. 1.  
         [0026]    In addition to the sub-floor embodiment of FIG. 1, the invention may be used to supply golf balls onto tees above a floor level. For example, a ball supply arm may swing to and from the position of the tee, so that the supply arm has a lowered position for feeding golf balls and a raised position to allow a golf ball to be driven.  
         [0027]    In general, there is a significant height difference from the tee height for the driver and the tee height for the pitching wedge, but adjustment of the tee height can be carried out using the same method that was described for supplying balls beneath the floor. In FIG. 1, a tee height adjustment member may be used. The tee height adjustment member  70  of FIGS. 1 and 3 includes a push switch  71 , the CPU  50 , the tee raising and lowering system  60 , an upper limit switch  72  and a lower limit switch  73 . When the main switch  71  is pressed with a golf club, a foot, or the like, the CPU  50  causes the reversible motor  61  to advance forwardly, thereby setting the tee  10  at a higher desired height. However, continuous pressing of the main switch  71  causes a protrusion  74  fixed to the vertical slider  64  to press the upper limit switch  72 . The activation of the upper limit switch causes the reversible motor  61  to reverse in direction, so that the tee will descend to a desired lower position if the pressure on the main switch  71  is released. Without releasing the main switch, the motor will continue until the protrusion  74  depresses the lower limit switch  73 , causing the reversible motor to again run forwardly.  
         [0028]    The attachment positions of the upper limit switch  72  and the lower limit switch  73  can be adjusted to meet the preferences of users. Moreover, the shape of the vertical slider  64  can be changed to accommodate the airflow detector  40  and the mini-blower  21 . Thus, the tee device may be formed in a single unit. The-position of the airflow detection box  23  in the tube  22  should then be moved to the end part closest to the mini-blower, so that only the tee  10  and the link to the tube  22  are disposed outside of the frame. This protects the airflow detector and the mini-blower, as well as other structural parts of the tee device.  
         [0029]    As is clear from the description, the tee device for golf practice is comprised of a cylindrical tee  10  in an upright position, with a vertical passageway  13  extending to an open upper end  11 . An airflow supply mechanism  21  provides airflow through the passageway inside the tee. A golf ball setting mechanism  30  for placing a golf ball on the tee is controlled by a detection arrangement  40  for (1) detecting when a golf ball has been placed on the upper end of the tee and (2) detecting when the golf ball is no longer present on the tee. The detection steps are implemented by monitoring airflow through the tee using the detector  40 . Placing a golf ball on the upper end of the tee substantially stops the airflow through the tee, causing the butterfly board  41  to move to the rest position P 2 . As a result, the CPU  50  will receive an airflow-stoppage detection signal. This signal causes the CPU to activate the motor  61  to move the tee until the golf ball  15  is above the level of the floor  16 . When the golf ball is struck by a golf club, airflow through the tee will return, causing the detector  40  to transmit an airflow detection signal that results in lowering of the tee by the motor.  
         [0030]    In the described embodiment of the invention, the detector  40  includes a moving member that is responsive to airflow. When the moving member is in a rest position, the airflow-stoppage detection signal is transmitted. On the other hand, when air pressure causes the moving member to be displaced, the airflow detection signal is generated. The position of the moving member can easily be detected by using an optical sensor, but other sensors may also be used.  
         [0031]    The moving member that has been described includes a butterfly board  41  that is supported to swing relative to an axis defined by support rods  42 . The butterfly board includes a perpendicular protrusion  43  that blocks the passage of light when the butterfly board is in the rest position. This construction is convenient, has a high reliability, and is easily maintained. Testing is made easy by allowing the support rods to extend to the exterior of the detection box  23 , allowing a person to manually rotate the butterfly board. Moreover, the optical sensor unit  45  is easily removed and replaced.  
         [0032]    The golf ball setting arrangement of the invention is controlled by the airflow-stoppage detection signal. Golf ball setting operations are suspended until a set golf ball is no longer on the upper end  11  of the tee  10 . Thus, until the golf ball is removed from the tee, any placement operations of another golf ball are stopped.  
         [0033]    As another aspect of the invention, the motor  61  may be used to adjust the position of the ball. The pressing of the main switch  71  will cause the ball to rise relative to the floor  16  until the switch is released or the contact of a protrusion  74  with an upper limit switch  72  reverses the motor. Similarly, when the motor is reversed, the golf ball will continue to descend until the main switch  71  is released or the protrusion  74  contacts the lower limit switch  73  that reverses motor direction.  
         [0034]    While the invention has been described and illustrated with reference to use with a golf ball tee device, the invention may be used in other applications. For example, monitoring airflow through a tee device may be used in baseball and softball tee devices for practicing hitting.