|Publication number||US2515847 A|
|Publication date||Jul 18, 1950|
|Filing date||Apr 13, 1945|
|Priority date||Apr 13, 1945|
|Publication number||US 2515847 A, US 2515847A, US-A-2515847, US2515847 A, US2515847A|
|Inventors||Carl W Winkler|
|Original Assignee||Carl W Winkler|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (8), Referenced by (64), Classifications (13)|
|External Links: USPTO, USPTO Assignment, Espacenet|
July 18, 1950 c. w. WINKLER sURFAcING MATERIAL Filed April 13, 1945 INVENTOR. BY 64,21.V M( W/MQ fe.
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Patented July 18, 1950 UNITED .S TAT ES 'rENT OFFICE SURFACING MATERIAL Carl W. `Winkler, Clay Township, St. Joseph County, Ind.
This `invention relates to surfacing material.
It is sometimes desirable "to provide a synthetic surface which will closely simulate the properties of a natural surface. For example, it may be desirable to provide a playing s-urface which possesses such properties 'that it permits 'a game to be played thereon under the same conditions presented by a natural playing surface. That is, the playing surface is to have the same feel; the same surface texture; and the 'same resilience and other properties which a natural "surface, such as turf, possesses. ASuch playing surfaces may be used either in interior installations, or out-of-doors. In the latter case they must be waterproof and weather resistant; and their advantage may lie in reduction of upkeep costs.
One application of the invention is for use as a putting green for a golf course. Putting greens require constant care, as watering, rolling, fertiliz'ing, seeding, weeding and cutting. The cost of such care is very high. Consequently, a surfacing material which possesses properties permitting golf to be played thereon in substantially the same manner as golf played on a natural putting green, can be Aused to materially reduce maintenance and operating costs olf golf courses.
The primary object of the invention is'to provide a surfacing material possessing the properties and advantages mentioned above.
A further Objectis to provide a surfacing material for exterior use which will not deteriorate when subjected to changing weather conditions, which provides drainage for water, and which can be taken up during winterjweather.
A further object is to provide a surfacing material of laminated character which will con- 'form to any desired contour `characteristic of a playing vsurface without wrinkling or curling or otherwise exhibiting properties not desired in a playing surface. Y
Other objects will be apparent from the description, drawing and appended claims.
In the drawing:
Fig. l is a perspective view illustrating thesurfacing material applied to a golf putting green.
Fig. 2 is a sectional View illustrating the matenial installed, as in a vgolf course.
Fig. 3 is a fragmentary perspective View of the surfacing material.
Fig. 4 is a section-al View of a modified embodiment of the material.
Fig. 5 is a sectional View illustrating the manner in which sectionsof the material containing a golf ycup are employed.
The invention is illustra-ted in the drawings as faces.
2 applied to or used in a golf course to form the putting greens thereof. Numeral Ill of the `drawing designates the surface of the ground at the approaches to a putting green i I which is formed of "our new surfacing material. At the space which the putting green occupies, the ground :is dug to provide a shallow recess I2 to uniform depth at its margins and of desired contour or topography. The bottom of the recess is smoothed or leveled to form a rm foundation as by rolling. The bottom and 'side walls of the recess are treated, as by an oil or other material which prevents the growth of weeds at said sur- It is important, however, that adequate drainage be provided, and therefore the earth must not be packed too solidly or treated with any materia-1 LofV such character as to provide 'a continuous layer or surface `at the surfaces 'o'f said recess which will prevent seepage of water therethrough. To facilitate drainage, especially at low ground, in clay soil, or `in any location where drainage is poor, it may `be desirable 'to provide a special base surface layer at recess I'2, as a layer of gravel or mineral aggregate (not shown). In -some cases, it may be necessary to use drainage tile (not shown) in the manner well understood by those versed in the art o-f drainage. The surfacing material of which the golf green -is formed ris of laminated construction. Its thickness is uniform and its size and shape corresponds to the recess I2 whereby "it fits snugly therein, without cracks or c'revices between its edges and the marginal surfaces of recess I2. Likewise its upper or playing surface must not be bulged or wrinkled, and the margin of its upper surf-ace must merge or be flush with the surface I0 of the playing area at all points therearound. y The bottom lamination or layer I3 of the surfacing material is preferably strong and durable. Also, it is preferably sufficiently flexible o-r pliable to permit it to assume the contour of and to hug the bottom of recess I2 if the same is rolling or otherwise contoured in the manner and to the limited extent that golf greens are commonly contoured for the purpose of introducing the element of skill in putting thereon. Layer I3 will preferably be approximately one inch in thickness, and that thickness will be uniform throughout. Layer I3 may be made of such materials as hard rubber; wool, cotton or cellulose matting impregnated with waterproofing material to form. a fairly solid body; plastic sheeting; alpha cellulose; waterproofed plywood; or the like. Selection of the material used in any instance flexible material at its opposite faces.
will be determined by the conditions of use at the locale of installation. It is preferable, however, that layer I3 shall not possess any substantial degree of resilience or compressibility.
A layer I4 is superimposed upon layer I3, and is preferably approximately one-half inch in thickness. This layer should possess the properties of resilience and compressibility, and should yield upon impact to act as a buier without imparting any substantial rebound action to an object striking the same. must resist permanent deformation or depression incident to strain, pressure or impress. Spongy material, such as sponge rubber or plastic sponge serves well for these properties,` although any material characterized by myriad voids therethrough and by the properties of flexibility, limited resilience and shape or form retention or return may be used if suitably waterproofed.
Layer I5 is superimposed upon layer I4 and is preferably approximately one inch thick. Its
vproperties are preferably similar to those of layer I4, though somewhat lesser in degree. In other words, limited resilience, compressibility and yieldingness are desirable. In order to provide these properties sponge rubber or sponge plastic having smaller voids and greater mass per cubic At the same time it" inch than is characteristic of the material forming layer I4 may be employed. Also, to further reduce or limit the properties of compressibility and yieldingness of sponge material, it may be provided with continuous skins of rubber or other may either be formed integrally with the sponge material by processes well known in the art of vmaking sponge rubber, or may be separate layers ladhered to the faces of the sponge material. Ad-
herence of preformed facings may be preferable in cases where the surface skin or layer is required to be of a thickness which imparts substantial firmness and at least a measure of stiffness to layer I5. Alternatively, felted materials `having requisite physical properties and waterproof character may be employed.
The top layer I6 of the surfacing material may lbe a rug material or matting which provides a feel, texture and resistance to rolling of a golf ball thereon, which closely resembles close-cut grass. The material will preferably comprise a iiexible rm woven or felted backing I1, and a nap I8 formed of flexible fibers projecting-from 136" to 1% above the backing. The backing and the fibers will be suitably waterproofed, as by impregnation of the backing and coating of the fibers (without adherence of the fibers in bunches) by flexible plastic material or by rubber. Alternatively, the fibers themselves may be inherently water resistant or Waterproof. The nap I8 will preferably be colored to simulate the appearance of grass.
The various layers or laminations I3, I4, I5 and I6 above described may be secured together to -form a unitary material; or layers I3 and I4 may be secured together to form a base unit and layers f I5 and I6 may be secured together to form a surface unit. Suitable waterproof adhesives, of which different types, such as rubber cement, are
available, may be employed to firmly adhere or secure the layers in face engagement. This sef curing of the layers insures against displacement,
curling and other undesirable action or movement of the material and the individual. layers thereof. Where the material is adhered to form two separate units or sections, such as a base unit Such skins 1 4 and a surface unit, the base unit may be fabricated in small sections of such size that they may be easily handled. This facilitates removal, storage and replacement as is desirable in latitudes where the ground freezes during the winter. The surface unit is preferably unitary in such case, but is made of materials which can be rolled, thereby facilitating handling and storage.
The two unit make-up'of the material requires the provision of means to secure the layers together. One form of such means is illustrated in Fig. 4 and consists of brads or other fasteners I9 having small heads 20 which are driven or otherwise forced into the back I'I of layer I6 to an extent sufficient to insure against contact therewith by a golf ball which has been pitched or lofted onto the green. The shank of the brads or fasteners I9 will be of a length sufficient to -pass through layer I5 and penetrate and anchor into layer I4, and will preferably terminate above bottom layer I3. Consequently, the fasteners can move bodily with the surfacing material as layers I4 and I 5 are compressed or caused to yield upon impact. In this way, although the fasteners are rigid, they do not adversely affect or destroy the uniformity of the action or give of the surfacing material nor provide hard spots therein. The shanks of the brads may be barbed for secure anchorage with the layer I4 if desired, but such barbs should accommodate separation of the two units without excessive tearing of or injury to the layer I4.
Suitable provisions for drainage must be made to avoid water retention or waterlogging of the surfacing material during and following rainy weather. For this purpose, layer I5 may be provided with a multiplicity of substantially equispaced passages 2| therethrough. These passages should be of the smallest diameter which i will permit water to drain therethrough, in order that the uniformity of the surfacing material and of its properties will be maintained. `A multiplicity of substantially equi-spaced aligned passages 22 may be formed in the lower layers I3 and I 4. These passages will preferably extend at an angle and may be somewhat larger in diameter than passages 2i. Also, if desirable, wicks 23 of any suitable material may be mounted in passages 22 to facilitate or improve drainage.
It is common practice in the maintaining of golf courses to change the location of the cup 24 in the green from time to time. This practice Serves to avoid excessive wear or play at any particular part of the green and also to slightly change the conditions of play and to increase the skill requiredv of theplayer. The same practice can ybe used with greens formed of this surfacing material. An illustrative construction which accommodates this practice is illustrated in Fig. 5 and includes the provision in the surfacing material of a plurality of openings of the same size and shape. Each of said openings receives a laminated section 25 formed of the same materials of which the surfacing material is formed with a snug fit in a manner to provide a continuous overall upper playingsurface. The laminations of each section 25 are adhered together so that said sections are removable as a unit. One section 25 may have the cup 24 imbedded centrally therein and permanently connected thereto.
As an alternative tothe above construction, the openings and the sections 25 may be formed of the same size and shape as the cup 24, so that the cup 24 andy sections 25 are interchangeable. Except for their smaller size, sections 25 of this alternative embodiment will lbe of the same construction and will fit in and be removable from the openings in the surfacing material in the saine manner above described. y
Theuse of the surfacing material out--of-doors, `mounted.directly in and upon the ground as abovedescribed for the purpose of providing a synthetic 4golf green, faithfully reproducing the properties and characteristics of a natural golf green, is only one. .application of the invention. Other applications which may be suggested are indoor vgolf practice greens, and indoor and outdcbiplay-ing areasU for rlawn tennis, badminton and other games. Also, the material may be used in other relations, such as for floor coverings in cases or locations which require durability, strength, resilience or sound deadening or eliminating properties. In each such application, the properties desired will determine the materials selected for the different layers or laminations, in the same manner mentioned above with reference to selection of such layers for use as a golf green.
The surfacing material Will Wear Well because of its yielding properties. It can be colored to give any desired appearance, design or decorative effect. The securing of the layers will hold the material against wrinkling, curling or other undesired displacement. Also, except for cleaning in such installation as require it, the material does not require attention or upkeep as is required fior natural playing surfaces, and hence will be economical for many applications Where the cost of upkeep is high.
l. Surfacing material comprising a firm flexible mat having a short uniform nap, a thick mat-supporting lamination of rm sponge rubber characterized by limited compressibility and resilience, a comparatively thin intermediate resilient cushioning lamination of sponge rubber oi lesser density and greater compressibility i than said mat-supporting lamination, a rm strong base lamination having limited flexibility and negligible compressibility, and means for securing said mat and laminations in superimposed continuous face contacting engagement, said laminations each having a plurality of drainage passages therein communicating with passages in adjacent laminations, the passages in the upper lamination having a cross-sectional size sufficient to permit drainage but insufficient to materially alter the reaction of the lamination to impact.
2. Surfacing material comprising a rm flexible mat having a short uniform nap, a thick matsupporting lamination of firm sponge rubber characterized by limited compressibility and resilience, a comparatively thin intermediate resilient cushioning lamination of sponge rubber of lesser density and greater compressibility than said mat-supporting lamination, a firm strong base lamination having limited flexibility and negligible compressibility, and means for securing said mat and laminations in superimposed continuous face contacting engagement, said laminations each having a plurality of drainage passages therein communicating with passages in adjacent laminations, the passages in the upper lamination having a cross-sectional size suiiicient to permit drainage but insufficient to materially alter the reaction of the lamination to impact, and wicks extending through the passages in said intermediate and base laminations.
3. Surfacing material comprising a firm flex- 6 ible` mat having a short uniform nap, a thick matsupporting-y lamination of firmA sponge rubber characteribed by limited compressibility .and resilience, a comparativelyr thin intermediate resilient cushioning lamination of sponge rubber of lesser density and greater compressibility than saidmat-supporting lamination, a firm strong base lamination having limited flexibility and negligible compressibility, and means for securiing said mat and laminations' in superimposed continuous face contacting engagement, said laminations each having a plurality of drainage passages therein communicating with passages .infiadacent laminations,l the passages in the upper lamination having a cross-sectionalsize sufiicient to permit drainage but insumcient to materially alter the reaction of the lamination to impact, said upper mat-supporting lamination having a firm flexible resilient upper rubber web in bonded relation thereto and engaging said mat.
4. Surfacing material comprising a firm exible mat having a short uniform nap, a thick matsupporting lamination of firm sponge rubber characterized by limited compressibility and resilience, a com-paratively thin intermediate resilient cushioning lamination of sponge rubber of lesser density and greater compressibility than said matsupporting lamination, a firm strong base lamination having limited flexibility and negligible compressibility, and means for securing said mat and laminations in superimposed continuous face contacting engagement, said laminations each having a plurality of drainage passages therein communicating with passages in adjacent laminations, the passages in the upper lamination having a cross-sectional size sufficient to permit drainage but insufficient to materially alter the reaction of the lamination to impact, said base lamination being formed of non-cellular rubber.
5. Surfacing material comprising a firm ilexible mat having a short uniform nap, a thick matsupporting lamination of firm sponge rubber characterized by limited compressiblity and resilience, a comparatively thin intermediate resilient cushioning lamination of sponge rubber of lesser density and greater compressibility than said matsupporting lamination, a rm strong base lamination having limited flexibility and negligible compressibility, and means for securing said mat and laminations in superimposed continuous face contacting engagement, said laminations each having a plurality of drainage passages therein communicating with passages in adjacent laminations, the passages in the upper lamination having a cross-sectional size sufficient to permit drainage but insuflcient to materially alter the reaction yof the lamination to impact, said base and intermediate laminations being bonded together to form a preformed unit, and said mat and first named lamination being bonded to form a second preformed unit, said units being secured in superimposed relation by said securing means.
6. Surfacing material comprising a firm flexible mat having a short uniform nap, a thick matsupporting lamination of rm sponge rubber characterized by limited compressibility and resilience, a comparatively thin intermediate resilient cushioning lamination of sponge rubber of lesser density and greater compressibility than said matsupporting lamination, a firm strong base lamination having limited flexibility and negligible compressibility, and means for securing said mat and laminations in superimposed continuous face contacting engagement, said laminations each having a .plurality of drainage passages therein communicating with passages in adjacent laminations, the passages in the upper lamination having a cross-sectional size sufficient to permit drain- .agebut insuicient to materially alter the reaction A,to impact, said securing means constituting bracis extending through said mat and upper lamination and terminating'within the body of said intermediate lamination. CARL W. WINKLER.
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|U.S. Classification||428/17, 404/35, 428/91, 428/95, 404/2, 273/DIG.130, 404/32, 473/171, 428/96|
|Cooperative Classification||E01C13/08, Y10S273/13|