Field of the invention

The present invention relates to a golf tee and tee holder system which permits a golf ball to be supported at a variable height, and a method of using the tee holder system.

Background of Invention

Conventional golf tees used at driving ranges are rubber devices which, in use, are threaded through holes in a golf mat and rest on the surface which supports the golf mat. A given golf tee supports a golf ball at a fixed height. A golfer who wishes to change the height of the golf ball must remove the existing golf tee, and replace it with another tee of a different height (i.e. of a different length in the height direction). This action is cumbersome since it requires the golfer to lift the golf mat both to remove the existing tee and to introduce the new one. Furthermore, even if the golfer has multiple golf tees of differing lengths, he is only able to locate the golf ball at a selected one of a set of discrete heights: each corresponding to the height of a corresponding one of the tees. This situation is different from that on a real golf course, where the golfer can select a tee (e.g. a long tee or a short tee) and finely adjust the height of the tee by pushing it into the ground by a selected amount, and this factor introduces an unwanted disparity between a golf range and a real golf course.

Various proposals have been made for adjustable golf tees, but these tees are mainly intended for use on real golf courses rather than driving ranges. Furthermore, most proposed adjustable tees have great internal complexity, for example having two portions connected by a screw-thread so that their relative position can be adjusted. The complexity of this design makes it doubtful whether the tees could be produced at realistic cost. Summary of the invention

In general terms, the present invention proposes that a golf tee holder is provided comprising an extension element and a base element. The extension element is releasably connectable to a tee, and has a continuously variable height in relation to the base element.

In one form the extension element may be connectable to the tee using an arm which supports the tee spaced horizontally from the base element. This has the advantage that the base element and extension element may be above the level of the top surface of the golf mat without limiting the lowest height at which the tee can be supported over the mat. Preferably, the arm is an element separable from the extension element.

Preferably, the extension element is connected to the base element by a friction fitting which maintains the extension element by friction at a desired position in relation to the base element, unless the extension element is caused by a user to slide in relation to the base element. A friction fitting can be formed at low cost.

Preferably, the tee holder is used with multiple golf tees of differing heights, each of which is connectable to the extension section of the tee holder. Thus, an incremental adjustment of the height at which a golf ball can be supported is provided by replacement of the tee which is supported by the golf ball, and fine adjustment of the height at which the golf ball can be supported is provided by variation of the height of the extension element in relation to the base element. Brief Description of The Figures

Preferred features of the invention will now be described, for the sake of illustration only, with reference to the following figures in which: Fig. 1 is a perspective view of the base element of a tee holder which is a first embodiment of the invention; Fig. 2 is composed of Fig. 2(a) which is a perspective view of an extension element of the tee holder for use with the base element of Fig. 1 , and Fig. 2(b) which shows a section of the extension element of Fig. 2(a) in greater detail; Fig. 3 is a perspective view of a tee holder arm element for use with the extension element of Fig. 2; Fig. 4 is a cross-sectional view of a tee for use with the tee holder composed of the elements of Figs. 1 to 3; Fig. 5 is a side view of the tee of Fig. 4 connected to a tee holder base portion of Fig. 1 by the extension element of Fig. 2 and the arm element of Fig. 3; Fig. 6 shows an alternative form of the extension element shown in Fig 2; and Fig. 7 is a side view of the tee of Fig. 4 connected to the tee holder of Fig. 1 by the extension element of Fig. 6. Fig. 8 is composed of Fig. 8(a) which is a perspective view of an extension element of the tee holder for use with the base element of Fig. 1 , and Fig. 8(b) which is a cross-sectional view of the extension element of Fig. 8(a); Fig. 9 is a cross-sectional view of a tee for use with the tee holder composed of the elements of Figs. 1 and 8; Fig. 10 is a cross-sectional view of the tee of Fig. 9 connected to a tee holder of Fig. 1 by the extension element of Fig. 8; and Fig. 11 is a perspective view of a spacer for use with the tee holder of Fig. 1 and the extension element of Fig. 6 or 8;

Detailed Description of the embodiments

Referring firstly to Fig. 1 , the base element 1 of a tee holder which is a first embodiment of the invention comprises a circular hollow cylindrical portion 12 having an inner diameter b and an outer diameter c. A lip portion 14 extends radially inwardly from the upper end of the cylindrical portion 12, and encircles a circular opening 13 of diameter a. The opposite end of the cylindrical portion 12 of the base element is connected to a circular plate 11 having a diameter greater than c. The centre of the circular plate 11 is on the axis of the cylindrical portion 12, and the circular plate 11 includes a circular opening at its centre.

The extension element 2 of the tee holder shown in Fig. 2(a). It comprises a solid cylindrical shaft 21 having a circular cross section of diameter d. Two discs 22, 23, each having a central circular aperture of a diameter slightly greater than d, are removably connected to the shaft 21 , for example by screw-threaded engagement means provided on the shaft 21 and the inwardly-facing surfaces of the discs 22, 23 which surround the respective aperatures. The outer diameters of the discs 22, 23 are respectively e and f, both of which are greater than a. f is in fact in the range b > f > a, and f is smaller than the diameter of the circular opening in the circular plate 11. The shaft 21 is further provided with a soft rubber pad 24 at its lower end. The pad 24 has an outer diameter g, which is slightly greater than b. Fig. 2(b) shows in cross-section the lower part of the shaft 21 and the profile of the pad 24. It includes a circular rim 25 adhered to the lower end of the shaft 21. The third element of the tee holder is the arm element 3 shown in Fig. 3. It includes a main arm member 34 having at one end an upper loop 31 of inner diameter h and outer diameter i, and a lower loop 32 of inner diameter j. Diameter j > c and j > e, and diameter h > d but h < e. At the other end of the arm member 34 is a third loop 33 having an inwardly facing screw threaded surface.

Turning now to Fig. 4, a tee 4 for use with the tee holder is shown. Typically, this tee is formed of rubber. The tee 4 has an upper portion 42 of conventional shape for supporting a golf ball, and a hollow cylindrical body portion 43 defining a cylindrical cavity. A screw threaded area 41 is provided on the outer surface of the body portion 43 at its lower end. A lip extends radially inwardly for a short distance from the inner surface of the body portion 43 at its lower end, so that there is a hole on the axis of the body portion 43 which is of slightly smaller diameter than the cylindrical cavity within the body portion 43.

An inner tee element 47 is located within the cylindrical cavity. It comprises a head portion 45 which slides freely on the inner surface of the body portion 43 within the cylindrical cavity, and a tail portion 46 which is threaded though the hole at the lower end of the cylindrical cavity defined by the lip. The head portion 45 is of greater diameter than the hole defined by the lip, so that inner tee element 47 cannot exit from the cylindrical cavity through that hole. Furthermore, the upper portion 42 of the tee includes another lip 48 defining a circular opening of diameter less that the head portion 45, so the head portion 45 is trapped within the cylindrical cavity in the tee 4. Apart from that however, the tail portion 46 can hang to any distance out of the lower end of the tee 4.

We now turn to an explanation of how the tee holder is assembled from its elements 1 , 2, 3, and attached to the tee 4 to form the configuration shown in Fig. 5. To begin with, the cylindrical portion 12 of the base element 1 is threaded through a circular opening in a golf mat 7 from the underside, the opening having a diameter larger than c but smaller than the diameter of the circular plate 11 , so that the circular plate cannot pass through the hole.

The circular opening in the circular plate 11 of the base element 1 has a diameter greater than f and g, so that, when the disc 22 is not connected to the shaft 21 , but the disc 23 is connected to the shaft 21 , the shaft can be inserted upwardly through the circular opening in the plate 11 into the cylindrical cavity within the cylindrical portion 12 of the base element 1. There the pad 24 deforms to have an outer diameter b, and develops a friction between itself and the inner wall of the cylindrical portion 12 of the base element 1 which is sufficient to maintain the longitudinal position of the shaft 21 within the cylindrical cavity in the cylindrical portion 12 of the base element 1. In this respect, the shaft 21 resembles the plunger of a hypodermic syringe, which is maintained by friction at a fixed location within the syringe unless it is longitudinally moved by a doctor. The top of the shaft 21 extends out of the cylindrical portion 12 of the base element 1 through the opening 13. The disc 22 is then connected to the shaft 21 , so as to prevent the top of the shaft from passing back though the opening 13 into the cylindrical cavity in the cylindrical portion 12 of the base element 1.

The arm element 3 is then attached to the combination of the base element 1 and the extension element 2 by threading the top of the shaft 21 through the loop 32, and then threading the cylindrical portion 12 through the loop 32. At the same time, the top of the shaft 12 threads through the loop 31 , until the loop 31 comes to rest on the upper surface of the disc 22. The arm element 3 is now supported on the extension element 2, but it can rotate about the base element 1 , with the loop 32 sliding on the outer surface of the cylindrical portion 12 of the base element 1. The lower end of the body 43 of the tee 4 is then inserted into the hole defined by the loop 33 and the tee is rotated so that the threaded surface 41 becomes attached to the inner threaded surface of the loop 33. The configuration of the tee 1 and the tee holder composed of the elements 1 , 2, 3 is shown in Fig. 5.

Note that the position of the extension element 2 can be continuously varied within the cavity defined by the cylindrical portion 12 of the base element 1 , and therefore the height of the tee 4 can be continuously adjusted. As all positions the tail 46 rests on the upper surface of the golf mat 7 and gives stability to the tee 4. A golf ball can now be placed on the head 42 of the tee 4. When it is hit by a golf ball, the arm element 3 may rotate about the common axis of the base element 1 and the extension element 2. Alternatively, optionally elements may be provided (not shown) limiting, or even preventing, the rotation of the arm element 3 about this axis.

The length of the arm 34 should preferably be greater than the width of a big head driver, approximately 12 to 18 cm. The height extension of the arm 34 is typically 4 to 6 cm.

Note that the tee can be supported at a range of heights which corresponds to the range of longitudinal positions of the pad 24 within the cylindrical cavity of the cylindrical portion 12 of the base element 1. This range is preferably at least 2cm, so that a short tee of 2cm can be raised to the lower position of a 4cm tee and a 4cm tee can be raised to the lower position of a 6cm tee. This range of motion is independent of the thickness of the golf mat 7, and thus the present construction can be used with golf mats of arbitrary thickness. The height of the base element 1 above the golf mat is typically at least 3cm so that the loop 32 will not slide off the cylindrical portion 12 when the extension element 2 is raised by the maximum amount. If the golf mat 7 has a thickness of 3cm, the base portion 1 may be at least 6cm tall. The height of the top of the shaft 21 is typically about 2cm greater than the height of the top of the base portion. If a greater range of adjustment of the height is desired than the range of longitudinal positions of the pad 24 within the cylindrical cavity of the cylindrical portion 12 of the base element 1 , then this can be achieved by replacing the tee 4 with another tee of identical construction but in which the body portion 43 is of a different length. More generally, a plurality of tees can be provided so that incremental changes in the height of the ball can be achieved by selection of the tee, and continuous variation of the height between the increments can be provided by varying the position of the extension element 2 within the cylindrical portion 12 of the base element 1. Note that in principle, it would be possible for the golf ball to be placed directly on the loop 33, and driven from there. In other words, the loop 33 would play the role of a tee, connected to the shaft 12 via the arm member 34 and loops 31 , 32.

As described above, in a first form of the present invention, the golf tee is connected to the extension element via an arm element, as shown in Fig. 3. However, we now turn to a second form of the present invention, in which the golf tee is directly connected to the extension element. Referring to Fig. 6, a second embodiment 20 of the extension element in accordance with the second form of the present invention is shown in cross-section. The extension element 20 has a cylindrical body 29 of outer diameter q, which is slightly less than b, and a height typically of about 1cm. The body 29 is partially hollow defining a cylindrical cavity 26 of diameter p. A screw-threaded area 27 is provided on the inner surface of the body 29 near the bottom of the cavity 26. The extension element 20 has a rubber pad 51 of identical construction to the pad 24, and adhered to the lower end of the body 29.

In use, the extension element 20 is inserted into the base element 1 of Fig. 1 when the base element 1 is located with its cylindrical portion 12 threading through an opening in a golf mat 70 of greater thickness than the golf mat 7 of Fig. 5, and the base plate 11 located below the mat. The threaded portion 41 of the tee 4 can then be inserted through the opening 13 in the cylindrical portion 12, into the cylindrical cavity defined by the cylindrical portion 12, and down to the top of the extension element 20. The tee 4 is then rotated to attach the threaded portion 41 to the threaded surface 27. The configuration is then as shown in Fig. 7. Once again, the position of the extension element 20 within the cylindrical cavity defined by the cylindrical portion 12 is continuously variable, and therefore the height of the head portion 42 of the tee is continuously variable simply by pulling or pushing it, and causing the pad 51 to slide on the inner surface of the cylindrical portion 12.

A third embodiment is shown in Fig.10. Again, this is a second form of the invention. Specifically, the extension element 80 and tee 9 shown in Fig. 9 are connected by clipping the extension element 80 onto the tee 9. Referring to Figs. 8a and 8b, the extension element 80 has a cylindrical body of outer diameter s which is slightly greater than b, the inner diameter of the base element 1. The body 89 of the extension element 80 includes an upper cylindrical cavity 81 of diameter x surrounded by a lip portion 83 extending radially inwards, and a lower cylindrical cavity 82 of diameter t. Thus the extension element has a generally "horse-shoe" shape, with a L-shaped cross-section.

Turning now to Fig. 9, the tee 9 for use with the extension element 80 is shown. The tee 9 has an upper portion 42 of conventional concave shape for supporting a golf ball and a hollow cylindrical body portion 43 defining a cylindrical cavity of diameter r. As with the tee shown in Fig. 4, it is typically made of rubber. The tee 9 is inserted through the opening 13 in the cylindrical portion 12 into the cylindrical cavity and down to the top of the extension element 80. The lower end of the tee 9 has a neck of narrowed diameter n which defined by a groove 91 provided on the vertical sidewalls of the tee 9 and encircling the longitudinal axis of the tee 9. The extension element 80 is attached to the tee 9 by clipping the lip portion 83 at the side of the upper cylindrical cavity 81 onto the groove 91 , where diameter n>x. The bottom portion 93 of the tee 9 is received in the lower cylindrical cavity 82 of the extension element, where the diameter t of the lower cylindrical cavity 82 is larger than the diameter p of the tee 9. The tee 9 which has a length k extends out of the cylindrical portion 12 of the base element 1 through the opening 13. Subsequently, the extension element 80 is inserted upwardly through the circular opening in the plate 11 into the cylindrical cavity within the cylindrical portion 12 of the base element 1. In the embodiment shown in Fig. 8a, the body 89 of the extension element has an open slot defined in it so that the extension element 80 can be compressed and inserted into the cylindrical portion 12. The assembled configuration is as shown in Fig. 10. As with the previously described embodiments, the longitudinal position of the extension element 80 within the cylindrical cavity and hence the height of the head portion 42 of the tee can be varied by applying a vertical pushing or pulling force to the tee 9. This vertical force correspondingly causes the extension element 80 which is securely engaged onto the tee 9 to slide along the walls of the cylindrical cavity. The extension element 80 is made of a resilient material which deforms to have an outer diameter of b when inserted into the cylindrical cavity and develops sufficient frictional force between itself and the walls of the cylindrical cavity so that it is maintained in a desired longitudinal position within the cylindrical cavity when a user is not adjusting its position. Typically, the extension element 80 has a higher Young's modulus than the rubber tee. For example, it may be made of PVC. The extension element 80 has a diameter s which is larger than the diameter a of the opening at the top of the base element so that the extension element 80 cannot pass through the top of the base element 1.

When a golf ball placed on the head 42 of the tee 4, 9 is hit, the upward force of the golf swing tends to urge the tee upwards along the cylindrical cavity of the cylindrical portion 12 and in some instances to its maximum height above the top of the base element 1. The golfer then has to re-adjust the tee to the desired height frequently. This may even be necessary after each swing which is highly inconvenient. In accordance with a preferred embodiment of the present invention, spacers 100 (shown in Fig. 11) in the form of a ring with an outer diameter j<b and inner diameter i > p are provided to restrict the upward sliding of the tee 4, 9 along the cylindrical cavity of the base element. In use, one or more spacers 100 are located in the cylindrical cavity where they are received in the space between the top of the extension element 20, 80 and the top of the base element. The body 43 of the tee 4, 9 is threaded through the central aperture of the spacer 100 before the extension element 20,80 is secured to the tee. Depending on the height of the spacers h and the number of spacers used, the maximum longitudinal position of the extension element 20, 80 and hence the maximum height that the tee 4, 9 is allowed to protrude above the top of the base element 1 can be fixed accordingly. In this way, the golfer able to choose his desired tee height and be spared the inconvenience of having to re-adjust the tee height so often.

The second form of the present invention is suitable when the golf mat 70 is of sufficient thickness that the continuous range within which the extension element 20, 80 is required to move can mostly be contained within the thickness of the golf mat 70. For example, the height of the base portion may be 3cm, approximately the thickness of the golf mat, and the extension element 20, 80 may be movable by 2cm. Thus a long tee of 4cm can be adjusted to have a height above the golf mat 70 of between 2cm and 4cm, while a super-long tee of 6cm can be adjusted to have a height above the golf mat 70 of between 4 and 6cm.

Once again, a set of two or more tees can be provided having different lengths of the body portion 43, so that an incremental change in the height of the golf ball can be achieved by replacing the present tee with one of different length. Continuous variation of the height of the golf ball between these discrete increments is achieved by sliding of the extension element 20, 80 within the base element 1.

Although the invention has been described above with reference to only three embodiments, many variations are possible within the scope of the invention as will be clear to a skilled reader. For example, all the elements may be formed of plastic, or alternatively of rubber.