US3891214A

US3891214A - Heat shrinking dartboard cage and one piece core

Info

Publication number: US3891214A
Application number: US424336A
Authority: US
Inventors: Francis E Scullin
Original assignee: Crown Recreation Inc
Current assignee: Harvard Sports Inc
Priority date: 1973-12-10
Filing date: 1973-12-10
Publication date: 1975-06-24
Anticipated expiration: 1992-06-24
Also published as: GB1468449A; CA1003454A; IT1021149B; AU7305474A; FR2254006A1; FR2254006B3; BR7410223A

Abstract

The dartboard of the present invention consists of a target core having a front target face, a peripheral side wall, and a rear face mounted within a one-piece plastic cage having a plurality of integrally formed and operatively interconnected area divider members located in a common plane and superimposed on at least a portion of the front face of the core to define therebetween a plurality of target areas on the front face of the core. A peripheral rim is integrally connected to at least one of the divider members and extends about the periphery of the core, perpendicularly to the plane of the area dividers. Flange or lip means is integrally connected to the rim and extends perpendicularly thereto over at least a portion of the rear face of the core in spaced relation to the plane of the area dividers so that the core is held in and operatively secured to the cage between the area dividers and the flange or lip means of the rim.

Description

United States Patent 11 1 Scullin 1 1 HEAT SHRINKING DARTBOARD CAGE AND ONE PIECE CORE I75] lnventor: Francis E. Scullin. Hzivertown. Pa.

[73] Assignee: Crown Recreation. lne., Hollis. NY.

[22] Filed: Dec. 10, 1973 21 Appl. No.: 424,336

[52] US. Cl 273/102 B; 156/86; 29/447 [51] Int. Cl. F4lj 3/00 [58] Field of Search 273/95 R, 102 R 102 B,

273/1052, 67 A; 264/D1G. 71; 156/86, 40/156; 29/447 [56] References Cited UNITED STATES PATENTS 2,076.357 4/1937 Tempest 273/102 B 2.813.258 12/1957 Stern 273/102 B 3.309.091 3/1967 Haeckcr 273/102 B 3 4117.523 10/1968 Winston 40/156 3.501.149 3/1970 Meyer 273/102 R 3.638.942 2/1972 Bassctt 273/67 A 1 1 June 24, 1975 Primary Examiner-Richard C. Pinkham Assixmnt E,\'aminerMarvin Siskind Attorney. Agent or F llfll-R1Chfll'd M. Rabkin l 57 1 ABSTRACT The dartbuard of the present invention consists of a target core having a front target face. a peripheral side wall, and a rear face mounted within a one-piece plastic cage having a plurality of integrally formed and operatively interconnected area divider membersJocated in a common plane and superimposed on atleast a portion of the front face of the core to define therebetween a plurality of target areas on the front face of the core. A peripheral rim is integrally connected to at least one of the divider members and extends about the periphery of the core, perpendicularly to the plane of the area dividers. Flange or lip means is integrally connected to the rim and extends perpendicularly thereto over at least a portion of the rear face of the core in spaced relation to the plane of the area dividers so that the core is held in and operatively secured to the cage between the area dividers and the flange or lip means of the rim.

14 Claims, 7 Drawing Figures 1 HEAT SHRINKING DARTBOARI) (AGE AND ONE PIECE CORE The present invention relates to dartboard constructions and more particularly to a dartboard construction for securing a cage or area divider to a core member.

Numerous types of dartboard construction have previously been proposed for securing a cage or area divider to a core member in order to section the target surface of the core into a plurality of scoring areas. Some early constructions. for example. used metal spokes and rings to form the dividers of the core surface, with the spokes secured to a metal rim surrounding at least a portion of the periphery of the core and being secured thereto by nails. staples or the like. More recently, molded plastic area dividers or cage members have been used in dartboard constructions. Such molded plastic dividers or cages typically consist of a plurality of radially extending spokes having one or more concentric ring members integrally formed therewith. In one form of such cage members. as shown in US. Pat. No. 3.300.2lo to Haecker. the ends of each spoke are bent to form projecting pins which are frictionally inserted into the core. In another form, also by Haecker and shown in LS. Pat. No. 3.309.09l. a cage is produced wherein an annular rim member is secured to the ends of the radially extending spokes and surrounds the periphery of the core member.

In the latter construction. the cage is secured to the core member by the provision of an adhesive layer between the core and either the rim members and/or the radial spokes. Alternatively. it has been proposed to secure cages of the type shown in Haecker to the core by inserting staples. tacks. or the like through the rim of the cage into the core material. With the use of an adhesive material. the adhesive represents an additional expense in the construction of the dartboard and also may well tend to smear onto the surface of the target area producing an unpleasant appearance. Still further. since the adhesive layer must be in direct intimate contact with both the core material and the surfaces of the cage. it is necessary that the cage be formed with extremely high tolerances so as to closely match the core surfaces. The requirements for such high tolerances in the production of molded plastic cages represents a still further expense in the manufacturing process.

On the other hand. where staples or tacks are used in lieu of an adhesive to secure the cage to the core. the tacks and staples often work loose from the core material thereby destroying the connection between the core and the cage. For this reason. the type of core material which can be used is severely restricted. since the core must have the ability to retain the staple or tack. Thus. core materials which are formed from laminated fibers or the like lying in planes horizontal to the target surface are not suitable for use in such previously proposed constructions since they do not provide an adequate binding surface for engagement with the staple as the staple or tack will often simply enter between two laminations and not form a secure connection. As a result. certain relatively inexpensive materials which would otherwise be suitable for dartboard cores, for example. cores formed of Celotex boards. have previously been unavailable for use in manufacturing dartboards. Moreover. in addition to requiring more expensive core materials. the stapling and tacking operation required by previously proposed dartboard constructions represent further expenses in the manufacturing process.

Accordingly. it is an object of the present invention to provide a relatively inexpensive dartboard construction which is durable in use.

Yet another object of the present invention is to provide a dartboard construction which will permit the use of horizontally laminated core material such as Celotex.

Another object of the present invention is to provide a dartboard construction in which a molded plastic cage is secured to a core member without the use of adhesives. staples, or tacks.

A still further object of the present invention is to provide an economical dartboard construction which can be readily assembled in the manufacturing process.

In accordance with an aspect of the present invention. a dartboard construction is provided in which a core member is secured to and retained in a one-piece molded plastic cage. The cage preferably has a plurality of area divider members consisting of radially extending spokes and at least one concentric circular rib which all lie in the same plane and overlie at least a portion of the front face of the core member in order to subdivide the surface area of the core into a plurality of individual target areas. The spokes and circular rib of the cage are operatively connected to a rim member that extends generally perpendicularly from the plane of the spokes. and has a peripheral configuration which is complementary to the peripheral configuration of the core. The rim of the cage is provided with a flange or lip member that extends inwardly from the rim in order to overlie a peripheral portion of the back surface of the core member. The cage is molded of a thermoformable material having the characteristic that the material shrinks slightly as it cools or agcs immediately after the molding process. By using this type of thermoformable material the cage can be formed so that the peripheral configuration of its rim is slightly greater than the peripheral configuration of the core member to which it is to be secured. Thus. immediately after the molding process for the cage. the core can be readily inserted into the cage between the radially extending spokes and the lip 0r flange means of the rim. Thereafter. as the cage cools or ages, the plastic material of which it is formed shrinks slightly so that the rim closely mates with the peripheral surface of the core and the lip members or flanges thereof extend over the back surface of the core to prevent removal of the core from the cage.

The above, and other objects, features and advantages of the present invention will be apparent from the following detailed description of illustrative embodiments thereof which are to be read in connection with the accompanying drawings. wherein:

FIG. I is a perspective view of a dartboard constructed in accordance with one embodiment of the present invention;

FIG. 2 is a rear perspective view of the dartboard illustratcd in FIG. I;

FIG. 3 is an exploded perspective view of the dartboard of FIG. I showing the insertion of the core member of the dartboard into the cage;

FIG. 4 is a partial sectional view taken along line 4-4 of FIG. 2;

FIG. 5 is a perspective view similar to FIG. I of another embodiment of the present invention;

FIG. 6 is a rear view of the dartboard shown in FIG. 5', and

FIG. 7 is a sectional view taken along line 7-7 of FIG. 6.

Referring now to the drawing in detail, and initially to FIG. I thereof, it will be seen that a dartboard III, constructed in accordance with one embodiment of the present invention, includes a core member 12 captured within a molded plastic cage member l4. Core I2, in this embodiment, is formed as a generally circular disk, having a height of predetermined dimension in order to define a side wall or edge [6 (see FIG. 3) between the front or targe face 18 and its rear face 20. Although core 12 can be formed of any convenient material, it has been found preferable to use relatively inexpensive relatively stiff board material such as, for example Celotex board which consists ofa central laminated fibrous material core 22 having paper or cardboard layers 24, 26 secured to opposite sides thereof to define the front target surface 18 and rear surface of core 12.

Cage I4 is formed of a molded thermoplastic mate rial, as for example by injection molding, and forms an area divider consisting of a plurality of radially extend ing spokes or ribs 28 integrally formed with a plurality of concentric circular rings or ribs 30. The spokes and circular ribs structurally mark off different target areas on the front surface 18 of core I2, which surface may be printed with any suitable marking or scoring indicia, as illustrated in FIG. I.

Spokes 28 are integrally formed with a rim member 32 which has a peripheral configuration in plan corre sponding to the peripheral configuration of the core 12 and a width which is substantially equal to the height of the side 16 of the core. As seen in FIGS. I and 2, the outermost peripheral ring or rib 30 may be integrally formed with the upper edge 34 of rim 32 in order to define a flange which overlies the circumferential peripheral portion of the top surface 18 of the core. However, it is contemplated that this outer rib 30 may be eliminated and the spokes 28 extend directly to the top edge 34 of rim 32. In either case, the spokes 38 and the circular ribs 30 are formed so that their lower surfaces lie in a common plane which is adapted to be engaged against the upper surface 18 of core 12. In addition, rim 32 is provided with an apertured hanger 35, as seen in FIG. I, to permit the dartboard to be hung on the wall by a tack, nail or the like.

Rim 32 also has inner lip or flange means 36 integrally formed therewith adjacent the back edge 38 of the rim, in order to overlie a peripheral portion of the back surface 20 of core 12. Thus, as seen in FIG. 2, rim 32 is provided with two lips or flanges 36, each of which define a portion ofa sector ofa circle and overlie a peripheral edge portion 40 at the back surface 20 of core 12. In this manner, the core [2 is trapped between the flange or lips 36 of the cage and the lower surfaces of the spokes 28 and circular ribs 30.

In order to facilitate the insertion of core 12 in the cage I4 the cage is initially molded, as for example in an injection molding machine, whle in a hot state, to a size which is slightly larger than the size of core 12. That is, the cage is formed so that the diameter of the rim 32 is slightly greater than the diameter of the core. In this manner, as soon as the molding operation is complete, the flat core 12 (as seen in FIG. 3) can be pushed downwardly through the open back ofthe cage (in the direction of arrow P in FIG. 3) between the lips or flanges 36 so that it is positioned between the spokes 28 and the flangesv Thereafter, the thermoplastic mate rial will shrink as it cools and ages with the result that the rim 32 of the cage will be drawn inwardly, as indi cated by the arrows A in FIG. 3, until it tightly engages the peripheral side 16 of the core I2.

Thus, seen in FIG. 4, rim 32 will move from the dotted line position thereof, at which it is located when initially formed, to the solid line position after aging so that it is tightly in engagement with the side I6 of the core 12.

In the cooled or final position of cage I4, shown in solid lines in FIG. 4, core 12 is trapped between flanges 36 and the lower surfaces of the spokes 28 and ribs 30. Accordingly, no adhesive material is required, as is the case with the Haecker structure; nor need any staples. tacks or the like be used. Moreover, this construction of the cage and dartboard permits a core material to be used which is less expensive than the spirally wound paper, cork or wooden boards previously proposed and, in particular, a core material having horizontal laminations, such as Celotex, can be used for the core.

FIGS. 5-7 of the drawing illustrate another embodiment of the invention wherein the core member 12 has a substantially greater surface area than the target area defined by spokes 28 and concentric ribs 30. In this embodiment of the invention cage 50, which encloses core I2, is also formed of an integrally molded thermoplastic material with the radially extending spokes 28 and concentric ribs 30 integrally formed therewith. However. the outermost rib 30 is integrally formed with a rim 52 that has a configuration in plan which conforms to the periphery ofthe generally rectangular core member 12 utilized in this embodiment. Thus, by this c0n struction a target area 54 is defined on the front surface 18 of core 12 along with an open or exposed area 56 adjacent to the target area. The open area 56 may have a plurality of recesses 58 formed therein for accommodation and storage of the darts used in the game.

In the embodiment of the invention illustrated in FIG. 5, the outermost rib 30 is integrally formed with an inwardly extending peripheral flange member 60 on rim 52 and is connected to flange 60 at three points 62. In this regard, it is noted that the minor dimension of rectangular core 12 of this embodiment is substantially equal to the diameter of the outer rib 30, while the major dimension of core I2 is substantially greater than the diameter of the target area.

As in the previously disclosed embodiment, rim 52 of cage 50 is provided with a plurality of flange or lip members 64 at its lower edge portion which are located to overlie the rear surface 20 of core 12 in order to capture the core between spokes 28, flange 62 and the lip or flange 64. The latter overlie a substantial peripheral portion of the back surface 20 in order to firmly retain the core within the cage.

As in the embodiment of the invention described with respect to FIG. 1, the embodiment of FIG. 5 is also formed of a thermoplastic material such as polyethylene or the like, having the characteristic that it will shrink upon aging or cooling. Thus, cage 50 is first thermoformed and, while still hot. the complementary rectangular core 12 is inserted therein between flange or lip members 64. Thus, for example, as shown in FIG. 7,

rim 52 initially takes the dotted line position shown therein when initially formed and. when cooled attains the solid line position wherein it is substantially in complete engagement with the side 16 of core 12 to tightly clamp and/or retain the core 12 therein.

It is noted that in order to keep the spokes 28 and ribs flat against the target surface 18 of core 12 in the embodiment of FIG. 5, the outer rib 30 may be provided with one or more pins 68 extending perpendicularly therefrom and inserted into the core material. Since the plastic material is relatively flexible. and since the upper end of ring 30 adjacent pin 62 is not se cured to rim 52 (which provides dimensional stability to the cage) it may be necessary to positively secure this portion of the ring to the core. The pin 68 thus serves simply to hold the rib 30 flat on surfce 18. while rim 52 serves to hold the core in a fixed position with respect to the cage itself. Of course, rim 52 may be provided with an apertured hanger 35, in order to mount the entire dartboard assembly on a wall or the like.

it is noted also that the spokes 28 and ribs 30 may be formed in a generally triangular configuration in section, as seen in FIGS. 4 and 7, so that a pointed edge thereof faces the direction in which the darts are thrown. Thus, in the event a dart inadvertently engages one of the spokes, its point is directed towards the core member by the inclined surfaces of the ribs and thus into one of the target areas.

Accordingly. it is seen that a dartboard construction is provided which is adapted to use a relatively light weight and inexpensive core material which permits the elimination of adhesives, staples, tacks or the like to secure the cage and area divider portion thereof to the core.

Thus, materials which normally would not be used in dartboard constructions, i.e.. materials which would have a tendency to de-laminate when secured to the rim of the cage by staples, tacks or the like, can be utilized with the cage construction of the present invention. Accordingly, a more durable dartboard construction is provided which is not only simpler to manufacture than previously proposed constructions but is also less expensive.

Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of this invention.

What is claimed is:

l. A dartboard comprising a target core having a front target face, a peripheral side wall, and a rear face, and a one-piece cage operatively secured to said core, said cage including a plurality of integrally formed operatively interconnected ribs located in a common plane and superimposed on at least a portion of said front face of the core to define therebetween a plurality of target areas on said front target face, a peripheral rim integrally connected to at least one of said ribs and extending about the periphery of said core perpendicularly to said plane, and flange means integrally connected to said rim and extending perpendicularly thereto and extending over at least a portion of said rear face of the core whereby said core is held in and operatively secured to said cage between said bars and said flange means; said core comprising a relatively stiff one-piece member; said cage and core being generally complementary in plan, and said cage being formed of a thermoplastic material having the characteristic of shrinking upon cooling whereby said one-piece relatively stiff core is adapted to be readily inserted in said cage between said ribs and said flange means as one flat piece when said cage is formed and is tightly held in the cage upon shrinkage thereof.

2. The dartboard as defined in claim 1 wherein said ribs include a plurality of radially extending ribs.

3. The dartboard as defined in claim 2 wherein said core and said cage rim are circular in plan, with each of said radially extending ribs being operatively connected to said rim.

4. The dartboard as defined in claim 3 including at leat one circular rib being formed integrally with said cage and concentric with said rim.

5. The dartboard as defined in claim 3 wherein said flange means comprise two spaced sector shaped flange elements extending perpendicularly to said rim and inwardly thereof over peripheral portions of said rear face.

6. The dartboard as defined in claim 1 wherein said core s formed of a fibrous laminated material having the laminations thereof extending generally parallel to the front and rear faces of the core.

7. The dartboard as defined in claim 6 wherein said core is formed of Celotex board.

8. The dartboard as defined in claim 2 wherein said cage includes at least one circular rib operatively secured to and integrally formed with said radially extending rib to define with said radially extending bars a circular-sectional target area.

9. The dartboard as defined in claim 8 wherein the front face of said core has a larger surface area than said target area, said radial ribs and circular rib overlying a portion of said front surface and said circular rib being integrally formed with and operatively secured at predetermined locations along its periphery to said rim; said rim having a configuration in plan which is complementary to the peripheral configuration of said core. whereby said core is secured in said cage with a portion of said front face of the core exposed outside of said target area.

10. The dartboard as defined in claim 9 wherein said core is generally rectangular in plan having a major dimension greater than the diameter of said circular rib and a minor dimension substantially equal to the diameter of said circular rib and target area; said rim having a rectangular configuration complementary to that of said core.

11. The dartboard as defined in claim 10 wherein said circular rib is secured at three points to said rim, said points being respectively located along two of the long sides and one of the short sides of the rim thereby to provide said exposed surface portion at one end of said front face of said core outside of said target area.

12. The dartboard as defined in claim 11 wherein said circular rib includes an integral mounting pin extending perpendicularly therefrom into said core, said pin being located on said circular rib at a position diametrically opposed to the point of connection of said circular rib to said one short side of said rim.

13. The dartboard as defined in claim 11 wherein said exposed surface portion of said core has a plurality of recesses formed therein, said recesses having a configuration selected to accommodate a dart therein.

14. The dartboard as defined in claim I wherein said rim has an integral apertured hanger tab extending outwardly therefrom.

Claims

1. A dartboard comprising a target core having a front target face, a peripheral side wall, and a rear face; and a one-piece cage operatively secured to said core, said cage including a plurality of integrally formed operatively interconnected ribs located in a common plane and superimposed on at least a portion of said front face of the core to define therebetween a plurality of target areas on said front target face, a peripheral rim integrally connected to at least one of said ribs and extending about the periphery of said core perpendicularly to said plane, and flange means integrally connected to said rim and extending perpendicularly thereto and extending over at least a portion of said rear face of the core whereby said core is held in and operatively secured to said cage between said bars and said flange means; said core comprising a relatively stiff one-piece member; said cage and core being generally complementary in plan, and said cage being formed of a thermoplastic material having the characteristic of shrinking upon cooling whereby said one-piece relatively stiff core is adapted to be readily inserted in said cage between said ribs and said flange means as one flat piece when said cage is formed and is tightly held in the cage upon shrinkage thereof.

6. The dartboard as defined in claim 1 wherein said core is formed of a fibrous lAminated material having the laminations thereof extending generally parallel to the front and rear faces of the core.

9. The dartboard as defined in claim 8 wherein the front face of said core has a larger surface area than said target area, said radial ribs and circular rib overlying a portion of said front surface and said circular rib being integrally formed with and operatively secured at predetermined locations along its periphery to said rim; said rim having a configuration in plan which is complementary to the peripheral configuration of said core, whereby said core is secured in said cage with a portion of said front face of the core exposed outside of said target area.

14. The dartboard as defined in claim 1 wherein said rim has an integral apertured hanger tab extending outwardly therefrom.