US3578542A - Simulated grass mat for driving golf balls - Google Patents

Abstract

A SIMULATED GRASS MAT HAVING SUBSTANTIALLY PERPENDICULARLY EXTENDING BLADES OR STEMS WHEREIN THE BLADES ARE ANCHORED IN A CIVITY SO THAT THEY BEND AND DEFLECT THE HEAD OF A GOLF CLUB RATHER THAN BEING SHEARED OFF;

THE MATERIAL OF THE MAT BEING SELECTED TO SIMULATE NORMAL TURF.

Description

y 11, 1 5. mm I 3,578,542

SIMULATED GRASS MAT FOR DRIVING GOLF BALLS Filed Oct. 21. 1968 Y PmoR ART.

im m v M W, I I

I 9' E whi mLA-whilm.1......

INVENTOR. BY STEVEN M\G\TZ Fig. 5

United States Patent 3,578,542 SIMULATED GRASS MAT FOR DRIVING GOLF BALLS Steven Migitz, 17 Whistler Hill Lane, Huntington, N.Y. 11743 Filed Oct. 21, 1968, Ser. No. 769,183 Int. Cl. A41g 1/00 US. Cl. 16121 9 Claims ABSTRACT OF THE DISCLOSURE FIELD OF THE INVENTION The present invention concerns simulated grass mats; more particularly, it concerns simulated grass mats which are suitable for use as surfaces from which golf balls may be driven.

DESCRIPTION OF THE PRIOR ART There are a number of imitation grass mat products in use. In general, the products are of an ornamental nature only and do not require or provide structural rigidity and durability. Where these qualities are provided, it is contemplated that the material will be subjected to primarily ordinary walking pressures and therefore the prime characteristic of the product is the resilience of the various fibers or fabrics employed. Many of the existing mats contain fibers, either individually or in groups, that are attached to a base material and are projected upwardly therefrom.

Up to the present time the shearing efliect of golf clubs has made it impossible to provide a driving mat that actually simulates the turf encountered during normal playing at a golf course. The woven mats customarily encountered at driving ranges do not have a significantly durable pile and do not have the same feel, or effect, as one encounters when hitting a ball on normal turf.

SUMMARY OF THE INVENTION The present invention is specifically concerned with imitation grass mats which can be subjected to the extreme shearing forces of the type created by a swinging golf club. It will be appreciated that the velocity attained by the head of a golf club at the time of impact with a golf ball is very high. It will also be appreciated that particularly with the irons, one experiences extreme shearing action between the leading edge of the club and the ground or surface upon which the ball rests.

It is the object of the present invention to provide an improved driving mat having a grass simulating pile surface.

It is another object of the invention to provide an improved golf driving mat having resilient pile that Will return to a flexible position following horizontal depres son.

It is also an object of the invention to provide an im- Patented May 11, 1971 proved golf driving mat wherein the base or substrate of the pile is made of a resilient material simulating the impedance of earth.

A still further object of the invention is to provide an improved golf driving mat having a flexible pile wherein the fibers project from cavities in a base material.

In accordance with the invention there is provided a golf driving mat having a base material with a plurality of cavities therein, and a plurality of simulated grass blades extending from the base of said cavities and projecting above the surface of said base material.

Further objects and the numerous features of the invention will become evident from the following description which is taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an illustration of a mat in accordance with the present invention;

FIG. 2 is a diagram showing a typical artificial grass mat of the prior art and the action of a golf club thereon;

FIG. 3 is an illustration of a second typical artificial grass mat of the prior art, and the effect of a golf club thereon;

FIG. 4 is a cross-sectional view showing the construction of a mat of the nature contemplated in applicants invention;

FIGS. 5A, 5B, and 5C are enlarged side cross-sectional views of the condition of a golf mat incorporating applicants invention at succeeding instants of time under the impact of a swinging golf club;

FIG. 6 is a diagrammatic view of a second embodiment of the invention; and

FIG. 7 is an enlarged view of a grass subassembly of the type that may be incorporated in the embodiment of FIG. 6.

DESCRIPTION OF THE APPROVED EMBODIMENT It is contemplated that a golf driving mat of the type suitable for convenient use would be in a rectangular form as shown in FIG. 1. Such mats may be used individually or in sets to provide a larger surface. The mat comprises abase 10 and a pile surface 11 which is suitably colored and textured to simulate grass. The simulated grass blades making up surface 11 are chosen from suitable plastic or rubber-like materials to exhibit the necessary resilience. In this regard, a variety of materials may be selected and the particular cross-section of each blade will depend upon the specific characteristics the material exhibits. The two prime requirements concerning the material are its resilience and resistance to shearing forces.

Before proceeding with a detailed explanation of the features of the present invention, it is believed constructive to consider the types of mats presently available in the prior art. The mat shown in FIG. 2 has a plurality ofblades 12 projecting vertically from abase 13. The blades are joined substantially directly to the surface in the base atpoints 14. In a mat of this type, when agolf club head 15 engages the mat as a result of a normal swing, there is a severe tangential shearing force atpoint 14. This force is directed against the shortest dimension of theblade 12 and with a scissor-like effectiveness shears ofi the blades. Such a blade is shown, for example, at 16.

In an attempt to overcome the difficulties of the type shown in FIG. 2 there have been provided woven mats such as shown in FIG. 3. Mats of this type have a woven surface 20 which may be an integral part of thebase 21. In some instances, simulated blades may be woven into the base and left projecting above the. mat surface. Such mats are extremely firm and are made of materials which will resist the continual pounding of golf clubs. The difficulty with this type of mat is that it in no way simulates the actual characteristics of turf. Thus, for example, when a golf club strikes the surface it has a tendency to bounce off as illustrated by dashedline 15. This is not a simulation of normal turf and does not provide the practising golfer with a normal feel.

One embodiment of the present invention is shown in FIG. 4. In this embodiment, a plurality of simulatedgrass blades 25 project vertically from the bottom ofcavities 26 in amat 27. The density and height of theblades 25 is determined by the thickness of each individual blade and the desire to create the illusion of grass. The cavities may vary in depth and configuration, it having been found that a depth of /8 to /4 of an inch is sufficient. Thebase 27 is made of a rubber-like material.

The unique features of the present invention will be appreciated by reference to FIGS. A through 5C. These figures represent the effect of a swinginggolf club 15 upon the simulated grass blades and mat. As shown in FIG. 5A, agolf club 15 has substantially reached the bottom of the swing. It is engagingblade 30 along a line substantially parallel to the upper surface ofbase material 33.Blade 30 has begun to bend as a result of the contact withgolf club head 15; but is has not yet reached theside 34 of its cavity.

In FIG. 5B, theclub head 15 has advanced a short distance and is now pressingblade 30 into theupper corner 35 of the cavity. Theblade 30 is considerably depressed to the left and has begun to depress succeedingblades 31 and 32. At this time, it should be appreciated that the movement of the club head is no longer in a direction perpendicular to the cross-sectional dimension ofblade 30. Rather, the bending ofblade 30 tends to slideclub head 15 along the side of the blade. This greatly reduces any tendency to cut the blade. It will also be appreciated that the resilience ofbase 33 is effective to permit deformation of thecorner 35 of the cavity from whichblade 30 extends. This further tends to deflect the club head and prevent any shearing effect uponblade 30.

In FIG. 5C, theclub head 15 has passed the point of origin ofblade 30 and is now sliding along the side thereof.Blade 30 is resting againstbase 27 and suitably deflects the club head without any shearing forces. The succeeding blades, 31 and 32, are depressed to a large extent as a result of the contact withblade 30 and will accordingly also avoid shearing elfects as a result of the rapidly moving golf club head. Those succeeding blades which are not directly contacted byblade 30 will successively experience the same deforming effect as has been described forblade 30. Thus, as a result of the unique anchoring of these blades, there is no shearing force and no damage to the mat. Still further, the resilience ofbase 33 has made it possible to simulate the impedance normally encountered when a club contacts the earth below normal turf.

The principles of the present invention are also applicable to other arrangements of projecting simulated grass blades. For example, FIG. 6 illustrates a mat wherein the grass blades project in groups from cavities of the nature described. In this instance, one suitable mat structure includes the use of asubstrate material 40 and aperforated base layer 41. Plugs ofsimulated grass 42 may be suitably disposed within each perforation and project above the surface oflayer 41 to provide the simulated grass effect. In this embodiment, the twolayers 40, 41 may be adhered in any convenient manner and, as

4 shown in FIG. 6, the grass plugs 42 may be secured in the perforations oflayer 41 by theirbase flange 43 which exceeds the diameter of the perforations. Of course, any suitable securing technique familiar to those skilled in the art may also be employed. A golf driving mat of this type has the advantage of an increased number of blades and hence denser appearance. The density of the simulated grass is of an advantage in that it makes more likely the interaction of blades illustrated, for example in FIGS. 5B and 5C. Hence the tendency to slide the club head and prevent shearing is enhanced.

FIG. 7 is an illustrative view of onegrass plug 42 of the type that might be used in connection with the embodiment of FIG. 6. This plug is provided with abase portion 43 having a diameter which exceeds that of the base of the blades. A plurality ofblades 34 project from the base portion and may be arranged in either a circle, square, or other suitable arrangement. In fact, the invention is not intended to be limited in any way and it is appropriate to provide such plugs in rows and columns.

When the invention is to be used in a prescribed position, it is also acceptable to use grooves in the mat runing transverse to the direction of golf club swing; wherein the side walls of the grooves function in the manner described for the side walls of the cavities. This construction provides the desirable features of the invention and, in some instances, will make manufacture more convenient and economical.

Still another embodiment of the invention relates to the inclusion of a resilient material within the cavities between the simulated blades and the walls of the cavities. Preferably, this material is more resilient than the base material. Still further, this material in suitable instances may be similar to the material of the simulated blades themselves. The use of such a filler material will add to the restorative powers of the simulated grass blades and prevent the accumulation of dirt in the cavities. In addition, it may improve the manufacturing aspects of mats according to the invention.

Several embodiments of the invention have been described and it will be apparent to those schooled in the art that modifications may be made without departing from the teachings herein. It is contemplated that the following claims cover all modifications coming within the spirit and scope of the invention.

What is claimed is:

1. A simulated grass mat comprising a base material having a plurality of cavities therein, and at least one simulated flexible grass blade secured to the bottom of each cavity and projecting above the surface of said base material, the cross-sectional area of each of said simulated grass blades being less than the cross-sectional area of said cavities by an amount to permit lateral movement of the blade in the plane of the surface of said base material.

2. A simulated grass mat according to claim 1, wherein said base material is resilient.

3. A simulated grass mat according to claim 1, wherein said cavities are substantially filled with a material more resilient than said base material.

4. A simulated grass mat according to claim 3, wherein the material filling said cavities is the same as the material used to fabricate said simulated grass blades.

5. A simulated grass mat according to claim -1, wherein said simulated grass blades are assembled in groups projecting from a base, with each group positioned in a separate cavity.

6. A simulated grass mat according to claim 5, wherein said base is formed of two adhered layers, the bottom layer being solid and the upper layer having perforations therein, said groups of grass blades being secured within said perforations.

7. A simulated grass mat according to claim 6, wherein said cavities are substantially filled with a material more resilient than said base material.

8. A simulated grass mat according to claim 1, wherein said mat is fixedly positioned and the grass blades are subjected to shearing forces in a known direction, said cavities being formed as grooves running transverse said known direction, the width of said grooves being greater 5 than the cross-sectional area of said simulated grass blades.

9. A simulated grass mat according to claim 1, wherein said grass blades and said base material are formed of one material as an integral unit.

6 References Cited UNITED STATES PATENTS 3,459,107 8/1969 Anderson et al. 273176UX 3,275,487 9/1966 Lemelson 161-67X 3,235,438 2/1966 Wisotzky 16167X PHILIP DIER, Primary Examiner US. Cl. X.R.

Images