BACKGROUND ART In these days, golf occupies a position as one of public leisure sports to the populace.

To play golf, a large amount of training for ball hitting and field adaptation should be specially preceded. However, many persons cannot afford to exercise gold in the golf field due to various conditions of the field such as location and postulates for usage.

Thus, many golf exercising centers are recently built so that more persons may practice the golf. In the golf exercising center, balls are supplied on an artificial lawn mat from an automatic supplying machine, and an exerciser hits the ball toward a net.

A flying distance of a golf ball is proportional to a speed of a golf club head at a moment of impact, that is, a moment when a golf club head hits a ball. Thus, when training golf in the exercising center, most golfers try to increase a swing velocity of the golf club head in order to exert more momentum to the golf ball at the instant of impact.

A current tendency of the golf is changing from technical-oriented golf to power-oriented golf. In other words, a hit preference of golfers changes from accuracy first and distance second to distance first and accuracy second.

Generally, the golfer measures and monitors swing velocity of a golf club head to increase swing velocity of a golf club. In this reason, the following devices have conventionally been used: an analog device for measuring swing velocity of a golf club head by mounting a mechanical device using gears and a device for measuring swing velocity comprising an electronic circuit using a receiver and a transmitter of infrared rays.

However, among them, the analog device for measuring swing velocity of a golf club head has some defects that there is a difference in weight between a golf club for measuring swing velocity and one for practical use since the mechanical device for measuring swing velocity is mounted to the golf club, and there can not be obtained accurate data for the swing velocity of a golf club head since the swing velocity data is provided in analog.

Further, in case of the optical device for measuring swing velocity using an electronic circuit using a receiver and a transmitter of infrared rays, the infrared rays output from the transmitter should be input into the receiver after being reflected by a face of the golf club head. However, if the face of the golf club head is open or closed

due to the change of swing plane, the infrared ray is not reflected accurately toward the receiver, so the receiver cannot detect movement of the golf club head and calculate.

In such a case, the measurement for swing velocity of the golf club head is impossible.

On the other hand, sellers of golf supplies generally put an advertisement in online or offline media such as a newspaper, a magazine or Internet in order to advertise various golf supplies like a golf club, a golf bag, a golf ball, golf shoes, golf gloves, a mat for putting exercise, a swing trainer and so on. However, such an advertisement has some drawbacks that it is impossible to focus the advertisement on a specific target, frequency of exposure of the advertisement is not exactly measured, and the exposure time is very short.

In order to overcome these problems, advertisement contents is printed on a partition near the hitting position in the golf exercising center, or a hanging placard is suspended on the net to draw attention of golf trainers.

However, when a golf trainer enters the hitting position, the eyes of the golf trainer are usually focused on a golf club head and a ball at first, and when hitting the ball, the eyes are naturally moving toward a flying spot of the ball. Thus, the ad contents printed on the partition cannot draw attention of the golf trainer. In addition, since being printed on the partition, the ad contents cannot be changed.

The hanging placard is somewhat possible to draw a little attention of the golf player while the ball flies toward the net where the placard is suspended. However, the hanging placard still has no differential factor to concentrate the eyes of the golf trainer, and external environments such as wind and rain may easily contaminate the placard.

DISCLOSURE OF INVENTION The present invention is designed to solve the problems of the prior art, and therefore an object of the invention is to provide an apparatus for measuring a swing velocity of a golf club head, which is capable of accurately measuring not only the swing velocity of the golf club head but also a flying distance of a ball according to the velocity, and does not malfunction though a swing plane of the golf club head is changed to some extent.

Another object of the invention is to provide an advertising apparatus for golf training using the above-mentioned apparatus for measuring a swing velocity of a golf club head so that a golf trainer unconsciously watches an advertisement by focusing the eyes of the golf trainer on the advertisement when the golf trainer takes a right posture for hitting a golf ball with watching the ball or checks a swing velocity of the golf club and/or a flying distance of the ball after hitting the ball.

In order to accomplish the above object, the present invention provides an apparatus for measuring a swing velocity of a golf club head, which includes a pair of magnetic sensor modules for sensing a magnetic field of a magnetized material, attached to the golf club head or a shaft near the golf club head, at different positions when a golf club is swung, and then respectively outputting digital pulse signals at different points of time ; a micro controller for calculating a swing velocity of the golf club head and a flying distance of a golf ball by using the time difference of the digital pulse signals output from the pair of magnetic sensor modules and a distance between the pair of magnetic sensor modules; and a display for displaying the swing velocity of the golf club head and/or the flying distance of the ball calculated by the micro controller.

Preferably, the magnetic sensor module includes a magnetic sensor for sensing a magnetic field of the magnetized material when the magnetized material advances into a magnetic field sensing radius, and then generating an analog electric signal; an amplifier for amplifying the analog electric signal output from the magnetic sensor; an ADC (Analog-to-Digital Converter) for converting the analogue electric signal output from the amplifier into a digital electric signal; and a microprocessor for converting the digital electric signal into a digital pulse signal and then outputting the digital pulse signal to the micro controller when the digital electric signal output from the ADC is as strong as the magnetized material is recognized as a magnetic body.

At this time, the display may display an average, a dispersion rate, a deviation or a standard deviation for the swing velocity of the golf club head and/or the flying distance of the golf ball according to the control signal of the micro controller.

Preferably, the display includes first and second display units, and the micro controller outputs the swing velocity of the golf club head to the first display unit and the flying distance of the golf ball to the second display unit.

According to another aspect of the invention, there is provided an advertising apparatus for golf training, which includes a frame installed closely to a general golf training mat; a measuring apparatus for measuring a swing velocity of a golf club head, the measuring apparatus including a display for displaying the swing velocity of the golf club head and a flying distance of a golf ball when the golf club is swung, the measuring apparatus being installed on an upper surface of the frame; and an advertisement board detachably installed on the upper surface of the frame at a position near the measuring apparatus and having an advertisement display on which an advertisement having

various characters and figures is printed.

Here, the measuring apparatus is substantially identical to the above-mentioned one.

Preferably, the frame includes an installation unit having a fitting groove of a thickness identical to the advertisement board so that the advertisement board is fit into the fitting groove; and a grasp unit having a finger insert groove integrally extended from the fitting groove so that the advertisement board is easily detached from the installation unit by a grasping action of the finger.

This advertising apparatus may further include a support member protruded on a bottom of the frame as much as a thickness of the golf training mat in order to make the frame contacted with a longitudinal side of the golf training mat so that the measuring means and the advertisement board are substantially supported on the upper surface of the golf training mat.

Preferably, the advertisement board includes a receiving portion formed therein so that the advertisement display is selectively put in or pulled out; and a transparent plate for covering the receiving portion so that the advertisement printed on the advertisement display is exhibited outward.

According to another aspect of the invention, there is also provided an advertising apparatus for golf training, which includes a body; a measuring apparatus for measuring a swing velocity of a golf club head, the measuring apparatus including a display for displaying the swing velocity of the golf club head and a flying distance of a golf ball when the golf club is swung, the measuring apparatus being provided on an upper surface of the body; an advertisement unit provided on the body and having a

sliding groove so that an advertisement board is selectively put in or pull out; a sliding groove cover combined to the body so that the sliding groove is selectively open or close; and a body fixing unit provided on a rear side of the body for fixing the body to a bottom near a longitudinal side of a golf training mat.

Here, the measuring apparatus is substantially identical to the above-mentioned one.

Preferably, the body fixing unit includes a first body fixer combined to the rear side of the body and a second body fixer combined to the ground, and the first and second body fixers are hinged pivotably.

BRIEF DESCRIPTION OF THE DRAWINGS These and other features, aspects, and advantages of preferred embodiments of the present invention will be more fully described in the following detailed description, taken accompanying drawings. In the drawings: FIG. 1 is a schematic block diagram showing an apparatus for measuring a swing velocity of a golf club head according to the present invention; FIG. 2 is a detailed block diagram showing the apparatus for measuring a swing velocity of a golf club head according to the present invention; FIG. 3 shows a golf club head swung by a golf trainer while the apparatus for measuring a swing velocity of a golf club head according to the present invention is being used; FIG. 4 is a conceptual view for illustrating that a magnetic sensor module shown in FIG. 1 outputs a digital pulse signal to be used for measuring a swing velocity of a

golf club head; FIG. 5 is a perspective view showing an advertising apparatus for golf training having the apparatus for measuring a swing velocity of a golf club head according to one embodiment of the present invention; FIG. 6 is an exploded perspective view showing the advertising apparatus for golf training of FIG. 5; FIG. 7 is a sectional view showing an advertisement board of FIG. 6; FIG. 8 is a perspective view showing an advertising apparatus for golf training having the apparatus for measuring a swing velocity of a golf club head according to another embodiment of the present invention; FIG. 9 is a perspective rear view showing the advertising apparatus for golf training of FIG. 8; FIG. 10 is a sectional view showing the advertising apparatus for golf training of FIG. 8, which is already installed; and FIG. 11 is a perspective view showing the advertising apparatus for golf training of FIG. 8, which is already installed.

BEST MODES FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, terms and words used in the specification and the claims should be interpreted not in a limited normal or dictionary meaning, but to include meanings and concepts conforming with technical aspects of the present invention, based on the face that inventors may appropriately

define a concept of a term to describe his/her own invention in a best way. Therefore, the configurations described in the specification and drawn in the figures are just most preferred embodiments of the present invention, not to show all of the technical aspects of the present invention. So, it should be understood that there might be various equalities and modifications to be replaced with them.

FIG. 1 is a schematic block diagram showing an apparatus 50 for measuring a swing velocity of a golf club head according to an embodiment of the present invention.

Referring to FIG. 1, the measuring apparatus 50 includes first and second magnetic sensor modules 10 and 20 installed at different positions for sensing a magnetic field of a magnetized material 5, attached to the golf club head or a shaft of the golf club near the golf club head, at different points of time when a golf club is swung, generating electric signals, converting the electric signals into digital signals, and then outputting digital signals ; a micro controller 30 for calculating a swing velocity of the golf club head and a flying distance of a golf ball by using the difference of output times of the digital pulse signals output from the first and second magnetic sensor modules 10 and 20 and a distance between the first and second magnetic sensor modules 10 and 20 ; and a display 40 for displaying the swing velocity of the golf club head and/or the flying distance of the ball calculated by the micro controller 30.

The magnetized material 5 preferably has a rubber as a matrix in which magnetic particles are dispersed. The magnetized material 5 may be configured as a detachable ring-shaped band which may be attached around a shaft near the club head, or a detachable adhering pad having an adhering surface so as to be attached to the head body except a face of the club head. In addition, the magnetized material 5 preferably

has so little weight as not to affect on the golf club head.

FIG. 2 is a detailed block diagram showing the apparatus 50 for measuring a swing velocity of a golf club head according to an embodiment of the present invention.

Referring to FIG. 2, the first magnetic sensor module 10 includes a first magnetic sensor 10a for sensing a magnetic field of the magnetized material 5 when the magnetized material 5 advances into a magnetic field sensing radius while the golf club is swung, and then generating an analog electric signal; a first amplifier 10b, e. g. OP AMP (OPerational AMPlifier), for amplifying the analog electric signal output from the first magnetic sensor 10a ; a first ADC (Analog-to-Digital Converter) 10c for converting the analogue electric signal output from the first amplifier 10b into a digital electric signal; and a first microprocessor 10d for determining whether when the digital electric signal output from the ADC is as strong as the magnetized material can be recognized as a magnetic body, and then, if so, outputting the digital electric signal as a digital pulse signal.

The second magnetic module 20 is configured identical to the first magnetic module 10. The first and second magnetic modules 10 and 20 are spaced apart as much as a predetermined distance (D). The first and second magnetic modules 10 and 20 also sense, at different positions, a magnetic field of the magnetized material 5 attached to the golf club while the club is swung, and then output digital pulse signals to the micro controller 30. Thus, two digital pulse signals output from the first and second magnetic modules 10 and 20 have a predetermined time difference.

The first and second magnetic sensors 10a and 20a may adopt magnetic sensor chips such as HMC1001/1002 or HMC1021/1022 manufactured by HONEYWELL co.

ltd, but not limited to those cases.

The micro controller 30 calculates the swing velocity of the golf club head on the basis of the time difference (T) of the digital pulse signals output from the first and second microprocessors 10d and 20d of the first and second magnetic sensor modules 10 and 20 and the distance (D) between the first and second magnetic sensor modules 10 and 20, and then calculates a flying distance of the golf ball by using the calculated swing velocity. And then, the micro controller 30 outputs the swing velocity of the golf club head to a first display unit 41 of the display 40, and the flying distance of the golf ball to a second display unit 42 of the display 40, in digits. Here, the first and second display units 41 and 42 may adopt an LED 7 segment or an LCD.

Now, an operation of the measuring apparatus 50 according to the present invention is described in more detail with reference to FIGs. 3 and 4.

FIG. 3 shows a golf club swung by a golfer while the measuring apparatus of the present invention is installed.

Referring to FIG. 3 together with FIG. 2, the first and second magnetic sensor modules 10 and 20 are installed on the ground or under a bottom 13, which is a mat, to be spaced apart from each other as much as a predetermined distance (D). The first and second magnetic sensor modules 10 and 20 are also set to sense a magnetic field generated from the magnetized material 5 attached to the golf club when the golf head passes through points A and B respectively while the golf club is swung, and then output corresponding digital pulse signals to the micro controller 30.

Accordingly, if the golf club head is positioned at the point A while the club is swung, the first magnetic sensor 10a of the first magnetic sensor module 10 senses the

magnetic field of the magnetized material 5 attached to the golf club head or the shaft near the head, and then applies an analogue electric signal to the first amplifier 10b.

The first amplifier 10b of the first magnetic sensor module 10 then amplifies the analogue electric signal output from the first magnetic sensor 10a and applies the amplified signal to the first ADC 10c. The first ADC 10c receiving the amplified analogue electric signal then converts the signal into a digital electric signal and applies the digital electric signal to the first microprocessor 10d. The first microprocessor 10d receiving the digital electric signal then determines whether the magnitude of the digital electric signal is as strong as the magnetized material 5 can be recognized as a magnetic body by comparing the magnitude with a set value stored in a memory (not shown) of the first microprocessor 10d, and then converts the digital electric signal into a digital pulse signal and then applies the digital pulse signal to the micro controller 30 if the magnetized material 5 is recognizable as a magnetic body.

Similarly, if the golf club head reaches the point B after passing through the point A while the golf club is swung, the second magnetic sensor 20a of the second magnetic sensor module 20 operates identical to the first magnetic sensor 10a.

In other words, the second magnetic sensor 20a of the second magnetic sensor module 20 senses the magnetic field of the magnetized material 5 attached to the golf club head or the shaft near the head, and then applies an analogue electric signal to the second amplifier 20b. The second amplifier 20b of the second magnetic sensor module 20 then amplifies the analogue electric signal output from the second magnetic sensor 20a and applies the amplified signal to the second ADC 20c. The second ADC 20c receiving the amplified analogue electric signal then converts the signal into a digital

electric signal and applies the digital electric signal to the second microprocessor 20d.

The second microprocessor 20d receiving the digital electric signal then determines whether the magnitude of the digital electric signal is as strong as the magnetized material 5 can be recognized as a magnetic body by comparing the magnitude with a set value stored in a memory (not shown) of the second microprocessor 20d, and then converts the digital electric signal into a digital pulse signal and then applies the digital pulse signal to the micro controller 30 if the magnetized material 5 is recognizable as a magnetic body.

FIG. 4 is a conceptual view showing the process that the magnetic sensor module shown in FIG. 3 outputs a digital pulse signal to be used for measuring a swing velocity of a golf club head.

Referring to FIG. 4, the first and second magnetic sensor modules 10 and 20 respectively have a predetermined magnetic field sensing radius. In case the magnetized material 5 moves from left to right in the drawing, the first magnetic sensor module 10 at first senses a magnetic field of the magnetized material 5 when the magnetized material 5 advances into its magnetic field sensing radius. Accordingly, the first magnetic sensor module 10 outputs a digital pulse signal to the micro controller 30.

Similarly, if the magnetized material 5 advances into the magnetic field sensing area of the second magnetic sensing module 20 by moving as much as the distance (D) between the first and second magnetic sensor module 10 and 20, the second magnetic sensor module 20 senses the magnetic field generated from the magnetized material 5 and then outputs a digital pulse signal to the micro controller 30.

After receiving the digital pulse signals respectively output from the first and second magnetic sensor modules 10 and 20, the micro controller 30 calculates a time difference (T) between the time (tl) when the pulse from the first magnetic sensor module 10 is input and the time (t2) when the pulse from the second magnetic sensor module 20 is input.

If the micro controller 30 calculates the time difference (T), a velocity of the gold club head (V) is calculated according to the following equation by using the distance (D) between the first and second magnetic sensor modules 10 and 20, which is stored in a memory (not shown) of the micro controller 30.

Equation 1 V = D/T = D/(t2-tl) The velocity (V) of the golf club head calculated by Equation 1 is output to the first display unit 41 by means of the micro controller 30.

In addition, the micro controller 30 calculates a flying distance of the golf ball according to the following equation on the basis of the swing velocity of the golf club head calculated by Equation 1.

Equation 2 Flying Distance of Golf Ball = Swing Velocity of Golf Club Head (m/sec) x (5. 0-5. 5) (yard).

Here, a constant multiplied by the swing velocity of the golf club head is a number known by statistics depending on the swing velocity of the golf club head, which may be a fixed value, or a variable value depending on the swing velocity of the golf club head for more exact calculation of the flying distance of the golf ball. If the number is a variable value, the micro controller 30 refers to a memory in which constants used for calculating a flying distance of a golf ball according to the swing velocity of the golf club head are already stored.

When a user swings the club head many times, the micro controller 30 accumulatively stores velocities of the golf club head and flying distances of the golf balls measured or calculated whenever the user swings the golf club in the memory.

The micro controller 30 may also calculate an average, a dispersion rate, a deviation or a standard deviation for the swing velocity of the golf club head and the flying distance of balls, and display them on the first or second display unit 41 or 42, when requested by the user.

In this reason, though not shown in the figures, it is apparent to those skilled in the art that the measuring apparatus 50 of the present invention may further include a control panel used for requesting data such as an average, a dispersion rate, a deviation or a standard deviation for the swing velocity of the golf club head or the flying distance of balls to the micro controller 30, and a program for processing the data may be loaded in the micro controller 30.

The measuring apparatus 50 of the present invention is capable of accurately measuring the swing velocity of the golf club head and the flying distance of the golf ball by using two magnetic sensor modules, and show low possibility of malfunction

through the swing plane of the golf club is changed to some extent since the magnetic sensor modules sense a magnetic field of the magnetized material.

In the present invention, the measuring apparatus 50 described above may be applied to an advertising apparatus for gold training.

FIG. 5 is a perspective view showing an advertising apparatus 100 for golf training according to an embodiment of the present invention, and FIG. 6 is an exploded perspective view of the advertising apparatus 100.

Referring to FIGs. 5 and 6, the advertising apparatus 100 equips the above-mentioned measuring apparatus 50 on one side thereof and displays a swing velocity of a golf club head and a flying distance of a golf ball on the display 40.

Preferably, the velocity of the golf club head is displayed on the first display unit 41 and the flying distance of the golf ball is displayed on the second display unit 42.

In addition, the advertising apparatus 100 makes a golf trainer unconsciously watch an advertisement by focusing the eyes of the golf trainer on the advertisement in an advertisement board 80 located adjacent to the first and second display units 41 and 42 when the golf trainer takes a right posture for hitting a golf ball with watching the ball or checks a swing velocity of the golf club and/or a flying distance of the ball after hitting the ball.

More specifically, the advertising apparatus 100 includes a frame 70 installed closely to a general golf training mat 60, the measuring apparatus 50 fixed on the frame 70 for measuring and displaying a swing velocity of a golf club head and a flying distance of a golf ball respectively, the advertisement board 80 detachably installed on an upper surface of the frame 70 so that an advertisement having various characters and

figures is printed is exposed outward, and a support member 90 installed on a bottom of the frame 70 in order to make the frame contacted with the golf training mat 60.

The golf training mat 60 is generally used for a user to train a swing technique of a golf club in a golf exercising center under the same condition as the game field for the purpose of preparing for actual play. The golf training mat 60 includes a base plate 61 made of rubber and having predetermined length and width, and an artificial glass adhered on the upper surface of the base plate 61.

The frame 70 is configured so that it may be contacted with a longitudinal side of the golf training mat 60 by the support member 90, and substantially laid upon the upper surface of the golf training mat 60. The measuring apparatus 50 for measuring a swing velocity of a golf club head and a flying distance of a golf ball and displaying their data is installed on the upper surface of the frame 70, and the advertisement board 80 for exposing a predetermined advertisement is positioned near the measuring apparatus 50.

In order to selectively attach or detach the advertisement board to/from the upper surface of the frame 70, the frame 70 includes an installation unit 71 for fixing the advertisement board 80 near the measuring apparatus 50, and a grasp unit 73 for easy attachment and detachment of the advertisement board 80 so that the advertisement may be changed as required.

The installation unit 71 has a fitting groove 72 of a thickness identical to the advertisement board 80. The fitting groove 72 is formed on the upper surface of the frame 70 so that the advertisement board 80 is fit into the fitting groove 72 and substantially fixed on the upper surface of the frame 70.

The grasp unit 73 has a finger insert groove 74 integrally extended from the fitting groove 72 so that the advertisement board 80 is easily detached from the fitting groove 72 by a grasping action of the finger.

FIG. 7 is a sectional view of the advertisement board of FIG. 6.

Referring to FIG. 7 together with FIG. 6, the advertisement board 80 includes an advertisement display 81 on which an advertisement including various characters and figures is printed, and a transparent plate 82 for protecting the advertisement display 81 and allowing the advertisement printed on the advertisement display 81 to be exposed outward.

The advertisement display 81 is made of a film on which images or texts for advertising various golf supplies such as a golf club, a golf bag, a golf ball, golf shoes, golf gloves, a mat for putting exercise, and a swing trainer. In addition, the advertisement display 81 may contain a name of golf-related or other company, an enterprise logo, a phone number and so on.

The transparent plate 82 has length and width suitable for fitting with the fitting groove 72 of the installation unit 71. A receiving portion 83 is formed in the transparent plate 82 so that the advertisement display 81 may be selectively put in or pulled out. The transparent display 81 is preferably made of transparent acryl so that the advertisement printed on the advertisement board 81 may be exposed through the upper surface when the advertisement display 81 is received in the receiving portion 83.

Alternatively, an advertisement board for multi-image display, which is capable of successively displaying various advertisement images printed on one film by using a refractive feature of a general line lens, may be used, not limited to the above

configuration in which the advertisement display 81 is put into and pulled out of the receiving portion 83 in the transparent plate 82. In addition, an LCD-type advertisement board for displaying a predetermined advertisement image by operation of general LCDs may also be used.

As shown in FIGs. 5 and 6, the support member 90 makes the frame 70 to closely attached to the longitudinal side of the golf training mat 60 so that the measuring apparatus 50 and the advertisement board 80 are supported on the upper surface of the golf training mat 80.

The support member 90 also includes a prop 91 protruded on the bottom of a longitudinal side of the frame 70 as much as a thickness of the base plate 61. Thus, when a trainer postures a fixed position on the golf training mat 60 in order to train for golf club swing, the frame 70 is closed attached to the front portion of the longitudinal side of the mat 60, which is substantially faced with the trainer.

Now, an operation of the advertisement apparatus of this embodiment is described in detail.

As shown in FIGs. 5 and 6, the golf training mat 60 is at first installed on a predetermined position of the ground.

Subsequently, the prop 91 of the support member 90 is closed attached to the longitudinal side edge of the golf training mat 60. Since the prop 91 is formed on the bottom of the longitudinal side of the frame 70 to have a height identical to the thickness of the golf training mat 60, the frame 70 is substantially supported on the upper surface of the longitudinal side of the golf training mat 60 firmly.

Then, the advertisement display 81 on which a predetermined advertisement is

printed is put into the receiving portion 83 of the transparent plate 82, and then the transparent plate 82 is fit into the fitting groove 72 formed on the installation unit 71 of the frame 70. Thus, the advertisement printed on the advertisement display 81 is exhibited outward through the transparent plate 82.

On the other hand, to exchange the advertisement display 81 for exhibiting another advertisement, a user inserts one of the index finger or the middle finger into the finger insert groove 74 of the grasp unit 73, and then lifts the transparent plate 82 upward with grasping the transparent plate 82 by the thumb. Then, the transparent plate 82 may be easily separated from the fitting groove 72. After that, the advertisement display 81 received in the receiving portion 83 of the transparent plate 82 is pulled out, and a new advertisement display 81 is input into the receiving groove 83.

If the advertisement display is exchanged, the transparent plate 82 is again inserted into the fitting groove 72.

When a golf trainer postures to hit a golf ball laid upon the golf training mat 60 with the advertising apparatus 100 being mounted to the golf training mat 60, the golf trainer may unconsciously watch the advertisement exhibited through the transparent plate 82 with fixing the posture. In other words, since the frame 70 to which the advertisement board 80 is installed is arranged to be faced with the golf trainer, the eyes of the golf trainer may be focused on the advertisement exhibited on the advertisement board 80.

After that, if the golf trainer swings the golf club head, the measuring apparatus 50 calculates a swing velocity of the golf club head and a flying distance of the golf ball according to Equations 1 and 2, and then the swing velocity is displayed on the first

display unit 41 and the flying distance of the golf ball is displayed on the second display unit 42.

On the other hand, the golf trainer stares at the flying ball hit by the swing behavior of the golf club, and then the eyes of the golf trainer are naturally moved toward the first and second display units 41 and 42 in order to check a flying distance of the golf ball.

Thus, the eyes of the golf trainer are naturally turned toward the advertisement board 80 arranged near the first and second display units 41 and 42 while the golf trainer checks data displayed on the first and second display units 41 and 42, so the advertisement exhibited on the advertisement board 80 is exposed to the golf trainer again.

This exposure of the advertisement is repeated while the golf trainer conducts golf training, so the advertisement effect is improved.

FIGs. 8 and 9 are perspective views respectively showing top and bottom of an advertising apparatus according to another embodiment of the present invention.

Referring to FIGs. 8 and 9, the advertising apparatus 110 for golf training includes a body 111, the above-described measuring apparatus 50 provided at one side of the body 111, an advertisement unit 114 provided on the body 111 and having a sliding groove 113 in which an advertisement board 112 is selectively put in or pull out, and a sliding groove cover 115 combined to one side of the body Ill so as to selectively open or close the sliding groove 112.

The sliding groove cover 115 may be combined to the body 111 by means of a screw 116, but not limited to that case. The measuring apparatus 50 includes the first

display unit 41 for displaying a swing velocity of a golf club head and the second display unit 42 for displaying a flying distance of a golf ball, similarly to the case of the advertising apparatus 100 according to the former embodiment.

The advertising apparatus 110 includes a body fixing unit 117 provided on a rear side thereof for fixing the body 111 to a bottom near a longitudinal side of the golf training mat 60. The body fixing unit 117 includes first and second body fixers 118 and 119 hinged pivotably, and the first body fixer 118 is combined to the rear side of the body 111 and the second body fixer 119 is combined to the ground near the golf training mat 60.

FIG. 10 is a sectional view showing the advertising apparatus 110 installed on the ground 120 near the longitudinal side of the golf training mat 60.

Referring to FIG. 10, the first body fixer 118 is fixed to the rear surface 121 of the body 111 by a screw, and the second body fixer 119 is fixed to the ground 120 by a screw. The body 111 is pivotable on a joint of the body fixing unit 117. Thus, when required, repair or maintenance of the golf training mat 60 may be easily conducted by pivoting the body 111 to the arrowed direction.

The advertising apparatus 110 of this embodiment is installed near the longitudinal side of the golf training mat 60 as shown in FIG. 11. In this state, the advertisement of the advertisement board 112 inserted into the advertisement unit 114 is naturally exposed to the golf trainer when the golf trainer takes a right posture for hitting a golf ball or checks a swing velocity of the golf club and/or a flying distance of the ball after hitting the ball through the first and second display units 41 and 42. Such advertisement exposure is continued while the golf training is executed, so the

advertising effect is improved.

The advertising apparatus 100 or 110 of the present invention preferably adopts the measuring apparatus 50 aforementioned, but as other measuring apparatus, for example'an apparatus for measuring a swing velocity of a golf club head using a resonance circuit'disclosed in Korean Patent Laid-open Publication No. 2000-63374 may also be adopted.

INDUSTRIAL APPLICABILITY According to the apparatus for measuring a swing velocity of a golf club head disclosed above, it is possible to accurately measure the swing velocity of a golf club head and a flying distance of a golf ball by using magnetic sensors. The magnetized material attached to the golf club is very light, so it hardly affects on the weight of the golf club. Thus, though the magnetized material is attached to the golf club, the swing velocity of the golf club head and the flying distance of the golf ball may be measured under'the substantially equivalent condition. In addition, since the magnetic sensors sense a magnetic field of the magnetized material, the swing velocity of the golf club head and the flying distance of the golf ball can be measured even though a swing plane of the golf club is changed to some extent.

The advertising apparatus for golf training according to the present invention, which includes an advertisement board near the measuring apparatus, makes a golf trainer unconsciously watch an advertisement by focusing the eyes of the golf trainer on the advertisement when the golf trainer takes a right posture for hitting a golf ball with watching the ball or checks a swing velocity of the golf club and/or a flying distance of

the ball after hitting the ball. Thus, attention to the advertisement is increased, so the advertising effect is maximized. In addition, since the advertisement may be easily exchanged, it is possible to display various advertisements in turn.

The present invention has been described in detail. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.