Form for constructing a thrower's circle

Abstract

A form for constructing a thrower's circle includes a pair of half sections. Each half section has an upper surface and a base surface and two full length members and two half length members. The full length members and the half length members are connected together substantially at right angles to form a rectangle with four corners. A corner brace is located in each of the four corners. An inside cross member and an outside cross member extend between the half length members and are generally parallel to the full length members. A pair of semi-circles, each having substantially the same diameter that is larger than the length of the half length members and less than the length of the full length members. Means are provided for securing the half sections together so that the semi-circles form a full circle. Tubes extend from the circle toward the base to drain water from with in the circle.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a form for constructing player's circle as used in field sports and, more specifically, for a form for constructing a circle for the throwing of hammers and shot put and a form for throwing discus.

2. Prior Art

In the field of sports, the throwing of either hammer or shot put or throwing discus, the player throws from a circular area in a specific location. In the past, such circular areas for throwing have been constructed in parts. Only too frequently, the result was an inaccurate product. Of even greater significance, such construction was labor intensive and thus time consuming and worst of all, expensive.

In accordance with this invention, a form for use in constructing such thrower's circles is prefabricated under manufacturing conditions thereby assuring accuracy and economy. The form can be readily transported and installed to produce an accurate circle for throwing that is permanent and economical

OBJECTS

The objects of this invention as follows:

1. To provide a form for constructing a player's circle that is prefabricated under manufacturing conditions to provide accuracy and uniformity to produce a highly accurate player's circle.

2. To provide a form for constructing a players circle which is economical to construct while assuring high quality.

3. To provide a form for constructing a players circle which is permanent and durable.

4. To provide a form for constructing a player's circle which form can be readily transported to a construction site.

These and other objects will be apparent to those skilled in the art by reading the detailed description of the invention set forth hereinafter.

SUMMARY OF THE INVENTION

A form for constructing a thrower's circle includes a pair of half sections. Each half section has an upper surface and a base surface. A pair of semi-circles each with the same diameter are mounted on the upper surface of the half section. Each circle has the same diameter. A means are also provided for securing the half sections together with the two semi-circles forming a full circle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of the form for constructing a players circle for throwing hammer and shot put with the form fully assembled.

FIG. 2 is a side elevation of the form shown in FIG. 1.

FIG. 3 is a perspective view of the form for throwing hammer and shot put fully assembled.

FIG. 4 is an exploded perspective view of the form shown in FIG. 3 showing the three manufactured components of the form prior to being assembled.

FIG. 5 is a plan view of the form for a player's circle for throwing discus with the form fully assembled on site.

FIG. 6 is a side elevation of the form shown in FIG. 5.

FIG. 7 is a perspective view of the form for throwing discus fully assembled.

FIG. 8 is an exploded perspective view of the form shown in FIG. 7 showing the two manufactured components of the form prior to being assembled on site.

BRIEF DESCRIPTION OF THE NUMERALS

• • 17 Upper Surface
  • 19 Base Surface
  • 21 side members
  • 23 outer members
  • 25 circle (shot put)
  • 27 toe board
  • 29 marks
  • 31 bolts
  • 33 nuts
  • 35 half sections
  • 37 half side members
  • 39 full side members
  • 41 corner
  • 43 brace
  • 45 semi-circles
  • 47 diameter
  • 49 inside full members
  • 50 outside full members
  • 51 circumference
  • 53 two cross members (Shot Put)
  • 55 inside cross members (Shot Put)
  • 57 outside cross members (Shot Put)
  • 59 tubes
  • 61 circle (Discus)
  • 63 outside cross member (Discus)
  • 65 inside cross member (Discus)
  • 67 Notches

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The form for constructing a circle for throwing a hammer and shot put are shown in FIG. 1 through FIG. 4. The form for constructing a circle for throwing discus is shown in FIG. 5 through FIG. 8. Both forms are very similar and are constructed in the same manner. The differences between the two forms are dictated by the requirements for a circle for throwing hammer and shot put and a circle for throwing discus. The form for constructing a circle for showing hammer and shot put will be described first but the numerals use as to describe that form will also used for the form for constructing a circle for throwing discus. The form for constructing a circle for throwing discus will be described after the form for throwing hammer and shot put but only to reflect the differences. Parts which are different will be assigned a different numeral.

The installation of the form is both fast and simple. Once the form is completely assembled, as discussed hereinafter, an excavation of the area is performed and is filled with crushed stone. The form is placed on the crushed stone in a level position. Cement is placed around and in the form up to the base of the circle. Once the cement has dried, dirt is placed over the cement only outside of the circle up to the top edge of the circle. The cement floor in the circle is shaped with a slight rise in the center of the circle to cause water to flow toward the edges of the circle. Once constructed, the circle is recessed within the surrounding ground.

Form for Hammer and Shot Put

Referring now to FIG. 1, the form is shown that is used to construct a circle for throwing hammer and shot put (hereinafter “Shot Put Form”). The Shot Put Form, when assembled, has a upper surface 17 and a lower surface 19 and is essentially a square having two side members 21 and two outer members 23. The circle 25, for use by the player, is mounted generally in the center of the square. The two outer members 23 and the side members 21 are essentially the same length.

The circle 25 includes a toe board 27 which is located toward one outer member 23 generally equally-spaced between two side members 21. The toe board 27 is constructed with a length suitable for more inexperienced players, most especially high school students and also has marks 29 on it to indicate the length of the toe board 27 for more advanced players, namely college students. The toe board 27 is preferably secured to the circle 25 by bolts 31 and nuts 33.

Referring now to FIG. 4, it can be seen that the Shot Put Form is preferably produced in a pair of half sections 35. Each of the two half sections 35 are the same except for the toe board 27.

Each half section 35 has two half side members 37 and two full side members 39, both of the two side members 37 are also outer members 23 of the assembled Shot Put Form. Each half side member 37 is substantially one-half the length of a full side members 39. The half side members 37 are secured to the full side members 39 substantially at right angles. At each corner 41 of each half section 35, a brace 43 is installed to strengthen the corners 41.

A pair of semi-circles 45 are placed on the pair of half sections 35. Each semi-circle 45 has a diameter 47 and the diameter 47 of each semi-circle 45 is placed along a full side member 39 generally equally distant between the half side members 37. The full side members 39 where the diameter 49 of the semi circles 45 is located are inside full members 49 and the inside full members 49 of the pair of half sections 35 are placed together. The opposite full side members 39 are the outside full members 50. When the two half sections 35 are together with the inside full members 49 abutting one another, the two semi circles 45 form the circle 25. The two half sections 35 form a square. The circle 25 has a circumference 51 and is generally located in the center of the Shot Put Form.

Each half section 35 has two cross members 53 which are parallel with the full side members 39, and extend from the half members 35. The two cross members 53, namely an inside cross member 55 and an outside cross member 57 are generally evenly spaced between the inside full members 49 and the outer members 23. The circle 25 for the Shot Put Form is supported at two points by each of the inside cross members 55 and at one point by each of the outside cross members 57 where the circumference of the circle 25 just extends over the outside cross member 57.

As shown in FIG. 3 and FIG. 4, a plurality of tubes 59, that are vertically oriented, are located about and secured to the inside of the circumference 51 of the circle 25. These tubes 59 provide drainage from within the circle 25. The tubes 59 direct water down to the crushed stone. As previously discussed, the cement in the circle 25 is raised slightly higher in the center to cause water to drain to the circumference 51 the circle 25 where the tubes 59 are located. In the upper surface 17, notches 67 may be cut into the inside full members 49 and the two cross members 53. The notches 67, which are used to hold Rebar, if desired, is inserted into the notches 67. Rebar, however, is not actually required. The notches 67 are aligned with one another generally parallel to the half side members 37.

Form for Discus

The form that is used to construct the circle 61 for throwing a discus (hereinafter “Discus Form”) is basically constructed in the same manner as the Shot Put Form.

The Discus Form is shown in FIG. 5 through FIG. 8 and does not include a toe board 27. The circle 61 of the Discus Form is larger that the circle 25 of the Shot Put Form. Due to the size of the circle of the Discus Form 61, an outside cross member 53 is placed closer to the outer member 23. Each inside cross member 65 is located substantially midway between the inside full member 49 and the outside cross member 53. Discus Forms are assembled and installed in the same manner as are Shot Put Forms. Notches 67 for Rebar may be added in the same manner as with the shot-Put Form. The notches 67 are aligned with the side members and are placed in the inside full members 49, the outside cross members 63 and the inside cross members 65.

It is to be understood that the drawings and the description are in all cases to be interpreted as merely illustrative of the principles of the invention rather that as limiting the same in any one way since it is contemplated that various changes may be made in various elements to achieve like results without departing from the spirit of the invention or scope of the appended claims.

Claims

1. A form for constructing a thrower's circle comprising: a pair of half sections, each half section having an upper surface, a base surface, two full side members having a length, and two half side members, the full side members connected to the half side members substantially at right angles to form a rectangle with four corners, each one of the pair of half sections generally having the same dimensions, one full side member of each of the pair of half sections comprising an inside full side member and the other full side member of each pair of half sections comprising an outside full side member;a pair of semi-circles, each semi-circle having an open diameter, the open diameter being less than the length of the full side member, each of the semi-circles mounted on one of the pair of half-sections wherein the open diameter extends along the inside full side member of the half section; andmeans for securing the pair of half sections together along the inside full side members wherein the pair of semi-circles form a full circle;wherein the full circle has an inside circumference having a plurality of tubes affixed thereto, each of the plurality of tubes extending in a direction from the upper surface of the half sections toward the base surface of the half sections.

2. The form for constructing a thrower's circle according to claim 1, further comprising a toe bar mounted on one of the semi-circles, the toe bar having a length adapted for use by amateur throwers and having marks positioned to indicate a length adapted for use by more advanced throwers.

3. The form for constructing a thrower's circle according to claim 1, further comprising braces positioned in each of the four corners.

4. The form for constructing a thrower's circle according to claim 1, further comprising at least one cross member extending between the two half side members of each half section.

5. The form for constructing a thrower's circle according to claim 4, wherein the inside full side members and the at least one cross member comprise notches adapted to receive the pair of semi-circles.

6. The form for constructing a thrower's circle according to claim 4, wherein the at least one cross member is positioned generally parallel to the full side members.

7. A form for constructing a thrower's circle comprising: a pair of half sections, each half section having an upper surface, a base surface, two full length members having a length, and two half length members having a length, the full length members connected to the half length members substantially at right angles to form a rectangle with four corners, each of the pair of half sections generally having the same dimensions, one full length member of each of the pair of half sections comprising an inside full length member and the other full length member comprising an outside full length member;an inside cross member and an outside cross member extending between the two half length members of each half section, the cross members positioned generally parallel to the full length members;a pair of semi-circles having substantially a same diameter, the diameter less than the length of the full length members and larger than the length of a half-length members, the semi-circles located along each of the inside full length members of each half section and generally centrally located between the two half length members, wherein each semi-circle is secured to one of the half sections; andmeans for securing the pair of half sections together along the inside full length members wherein the two semi-circles form a full circle, the full circle having an inside circumference with a plurality of tubes affixed vertically to the half sections, each tube extending in a direction from the upper surface of the half sections toward the base surface of the half sections.

8. The form for constructing a thrower's circle according to claim 7, wherein the inside cross members and the outside cross members are generally equally spaced between the inside full length members and the outside full length members.

9. The form for constructing a thrower's circle according to claim 7, wherein the outside cross members are located close to the outside full length members and the inside cross members are located generally midway between the outside cross members and the inside full length members.

10. The form for constructing a thrower's circle according to claim 7, wherein each semi-circle contacts the inside cross member at least two locations along the circumference of the semi-circle and also contacts the outside cross member at least one location on the circumference of the semi-circle.

11. The form for constructing a thrower's circles according to claim 7, further comprising a toe bar mounted on one of the semi-circles of the pair of semi-circles, the toe bar generally equally spaced between the half length members.

12. The form for constructing a thrower's circles according to claim 7, further comprising a toe bar mounted on one of the semi-circles of the pair of semi-circles, the toe bar having a length adapted for use by amateur throwers and having marks positioned to indicate a length adapted for use by more advanced throwers.

13. The form for constructing a thrower's circle according to claim 7, wherein the inside full length members and the inside cross members comprise notches generally aligned with the half length members.

14. The form for constructing a thrower's circle according to claim 7, further comprising braces positioned in each of the four corners.

15. A form for constructing a thrower's circle comprising: a plurality of sections, each section having an upper surface and a base surface and four right angles;a plurality of arcuate portions, each arcuate portion having a same diameter, a respective one of the arcuate portions mounted on the upper surface-of each of the plurality of sections;wherein when the plurality of sections is assembled together, the plurality of arcuate portions together forms a full circle; andat least one of a) a plurality of tubes affixed to the arcuate portions, the plurality of tubes extending from the upper surface of the sections toward the base surface of the sections, and b) a toe bar mounted on at least one of the arcuate portions.

16. The form for constructing a thrower's circle according to claim 15, wherein each of the plurality of sections comprises a plurality of side members and at least one cross member extending between the plurality of side members.

17. The form for constructing a thrower's circle according to claim 15, wherein each of the plurality of sections comprises a plurality of side members and at least one cross member extending between the plurality of side members, and wherein each arcuate portion contacts the cross member at least one location.

18. The form for constructing a thrower's circle according to claim 15, wherein each of the plurality of sections comprises a plurality of side members and at least one cross member extending between the plurality of side members, and the at least one cross member comprises a notch adapted to receive the arcuate portion.

19. The form for constructing a thrower's circle according to claim 15, comprising the plurality of tubes affixed to the arcuate portions, the plurality of tubes extending from the upper surface of the sections toward the base surface of the sections.

20. The form for constructing a thrower's circle according to claim 15, comprising the toe bar mounted on at least one of the arcuate portions.

21. The form for constructing a thrower's circle according to claim 15, comprising the toe bar mounted on at least one of the arcuate portions, the toe bar having a length adapted for use by amateur throwers and having marks positioned to indicate a length adapted for use by more advanced throwers.

22. The form for constructing a thrower's circle according to claim 15, wherein the full circle is disposed at a height greater than a height of the upper surface of the plurality of sections.

23. The form for constructing a thrower's circle according to claim 15, further comprising means for securing the plurality of sections together.

24. A form for constructing a thrower's circle comprising: a plurality of sections, each section having a plurality of side members and at least one cross member extending between the plurality of side members, and the plurality of sections defining an upper surface and a base surface;a plurality of arcuate portions, each arcuate portion having a same diameter, a respective one of the arcuate portions mounted on the upper surface of each of the plurality of sections;wherein when the plurality of sections is assembled together, the plurality of sections together forms a polygon and the plurality of arcuate portions forms a full circle disposed inside the polygon, and wherein a first portion of the base surface of the plurality of sections is disposed outside the full circle and a second portion of the base surface of the plurality of sections is disposed inside the full circle; andat least one of a) a plurality of tubes affixed to the arcuate portions, the plurality of tubes extending from the upper surface of the sections toward the base surface of the sections, and b) a toe bar mounted on at least one of the arcuate portions.

25. The form for constructing a thrower's circle according to claim 24, wherein each plurality of sections comprises four right angles.

26. The form for constructing a thrower's circle according to claim 24, wherein each of the plurality of arcuate portions contacts the at least one cross member at least one location.

27. The form for constructing a thrower's circle according to claim 24, wherein the at least one cross member comprises a notch adapted to receive at one of the plurality of arcuate portions.

28. The form for constructing a thrower's circle according to claim 24, comprising the plurality of tubes affixed to the arcuate portions, the plurality of tubes extending from the upper surface of the sections toward the base surface of the sections.

29. The form for constructing a thrower's circle according to claim 24, comprising the toe bar mounted on at least one of the arcuate portions.

30. The form for constructing a thrower's circle according to claim 24, comprising the toe bar mounted on at least one of the arcuate portions, the toe bar having a length adapted for use by amateur throwers and having marks positioned to indicate a length adapted for use by more advanced throwers.

31. The form for constructing a thrower's circle according to claim 24, wherein the full circle is disposed at a height greater than a height of the upper surface of the plurality of sections.

32. The form for constructing a thrower's circle according to claim 24, further comprising means for securing the plurality of sections together.

33. A form for constructing a thrower's circle comprising: a pair of half sections, each half section having an upper surface, a base surface, two full side members having a length, and two half side members, the full side members connected to the half side members substantially at right angles to form a rectangle with four corners, each one of the pair of half sections generally having the same dimensions, one full side member of each of the pair of half sections comprising an inside full side member and the other full side member of each pair of half sections comprising an outside full side member;a pair of semi-circles, each semi-circle having an open diameter, the open diameter being less than the length of the full side member, each of the semi-circles mounted on one of the pair of half-sections wherein the open diameter extends along the inside full side member of the half section;a toe bar mounted on one of the semi-circles, the toe bar having a length adapted for use by amateur throwers and having marks positioned to indicate a length adapted for use by more advanced throwers; andmeans for securing the pair of half sections together along the inside full side members wherein the pair of semi-circles form a full circle.

34. The form for constructing a thrower's circle according to claim 33, further comprising braces positioned in each of the four corners.

35. The form for constructing a thrower's circle according to claim 33, further comprising at least one cross member extending between the two half side members of each half section.

36. The form for constructing a thrower's circle according to claim 35, wherein the at least one cross member is positioned generally parallel to the full side members.

37. The form for constructing a thrower's circle according to claim 35, wherein the inside full side members and the at least one cross member comprise notches adapted to receive the pair of semi-circles.

38. A form for constructing a thrower's circle comprising: a plurality of sections, each section having an upper surface and a base surface;a plurality of arcuate portions, each arcuate portion having a same diameter, a respective one of the arcuate portions mounted on the upper surface of each of the plurality of sections;wherein, when the plurality of sections is assembled together, the plurality of arcuate portions together forms a full circle;wherein each of the plurality of sections comprises a plurality of side members and at least one cross member extending between the plurality of side members,wherein each arcuate portion contacts the at least one cross member at least one location; andat least one of a) a plurality of tubes affixed to the arcuate portions, the plurality of tubes extending from the upper surface of the sections toward the base surface of the sections, and b) a toe bar mounted on at least one of the arcuate portions.

39. The form for constructing a thrower's circle according to claim 38, wherein the at least one cross member comprises a notch adapted to receive the arcuate portion.

40. The form for constructing a thrower's circle according to claim 38, comprising the plurality of tubes affixed to the arcuate portions, the plurality of tubes extending from the upper surface of the sections toward the base surface of the sections.

41. The form for constructing a thrower's circle according to claim 38, comprising the toe bar mounted on at least one of the arcuate portions.

42. The form for constructing a thrower's circle according to claim 38, comprising the toe bar mounted on at least one of the arcuate portions, the toe bar having a length adapted for use by amateur throwers and having marks positioned to indicate a length adapted for use by more advanced throwers.

43. The form for constructing a thrower's circle according to claim 38, wherein the full circle is disposed at a height greater than a height of the upper surface of the plurality of sections.

44. The form for constructing a thrower's circle according to claim 38, further comprising means for securing the plurality of sections together.

45. A form for constructing a thrower's circle comprising: a plurality of sections, each section having an upper surface and a base surface;a plurality of arcuate portions, each arcuate portion having a same diameter, a respective one of the arcuate portions mounted on the upper surface of each of the plurality of sections;wherein, when the plurality of sections is assembled together, the plurality of arcuate portions together forms a full circle;wherein each of the plurality of sections comprises a plurality of side members and at least one cross member extending between the plurality of side members, and the at least one cross member comprises a notch adapted to receive the arcuate portionat least one of a) a plurality of tubes affixed to the arcuate portions, the plurality of tubes extending from the upper surface of the sections toward the base surface of the sections, and b) a toe bar mounted on at least one of the arcuate portions.

46. The form for constructing a thrower's circle according to claim 45, comprising the plurality of tubes affixed to the arcuate portions, the plurality of tubes extending from the upper surface of the sections toward the base surface of the sections.

47. The form for constructing a thrower's circle according to claim 45, comprising the toe bar mounted on at least one of the arcuate portions.

48. The form for constructing a thrower's circle according to claim 45, comprising the toe bar mounted on at least one of the arcuate portions, the toe bar having a length adapted for use by amateur throwers and having marks positioned to indicate a length adapted for use by more advanced throwers.

49. The form for constructing a thrower's circle according to claim 45, wherein the full circle is disposed at a height greater than a height of the upper surface of the plurality of sections.

50. The form for constructing a thrower's circle according to claim 45, further comprising means for securing the plurality of sections together.

51. A form for constructing a thrower's circle comprising: a plurality of sections, each section having an upper surface and a base surface;a plurality of arcuate portions, each arcuate portion having a same diameter, a respective one of the arcuate portions mounted on the upper surface of each of the plurality of sections; anda plurality of tubes affixed to the arcuate portions, the plurality of tubes extending from the upper surface of the sections toward the base surface of the sections wherein when the plurality of sections is assembled together, the plurality of arcuate portions together forms a full circle.

52. The form for constructing a thrower's circle according to claim 51, wherein each of the plurality of sections comprises a plurality of side members and at least one cross member extending between the plurality of side members.

53. The form for constructing a thrower's circle according to claim 51, further comprising a toe bar mounted on at least one of the arcuate portions.

54. The form for constructing a thrower's circle according to claim 51, further comprising a toe bar mounted on at least one of the arcuate portions, the toe bar having a length adapted for use by amateur throwers and having marks positioned to indicate a length adapted for use by more advanced throwers.

55. The form for constructing a thrower's circle according to claim 51, wherein the full circle is disposed at a height greater than a height of the upper surface of the plurality of sections.

56. The form for constructing a thrower's circle according to claim 51, further comprising means for securing the plurality of sections together.

57. A form for constructing a thrower's circle comprising: a plurality of sections, each section having an upper surface and a base surface;a plurality of arcuate portions, each arcuate portion having a same diameter, a respective one of the arcuate portions mounted on the upper surface of each of the plurality of sections; anda toe bar mounted on at least one of the plurality of arcuate portions; wherein, when the plurality of sections is assembled together, the plurality of arcuate portions together forms a full circle.

58. The form for constructing a thrower's circle according to claim 57, wherein each of the plurality of sections comprises a plurality of side members and at least one cross member extending between the plurality of side members.

59. The form for constructing a thrower's circle according to claim 57, wherein the toe bar comprises a length adapted for use by amateur throwers and comprises marks positioned to indicate a length adapted for use by more advanced throwers.

60. The form for constructing a thrower's circle according to claim 57, wherein the full circle is disposed at a height greater than a height of the upper surface of the plurality of sections.

61. The form for constructing a thrower's circle according to claim 57, further comprising means for securing the plurality of sections together.

62. A form for constructing a thrower's circle comprising: a plurality of structural sections that when assembled produce the form for constructing the thrower's circle;a plurality of arcuate portions, each of the plurality of arcuate portions mounted to one of the plurality of structural sections, and each of the plurality of arcuate portions having a radius;means for securing the plurality of structural sections together to provide the form for constructing the thrower's circle having a full circle formed from the plurality of arcuate portions; andat least one of a) a plurality of tubes adjacent to the arcuate portions, the plurality of tubes extending in a direction from an upper surface of the sections toward a base surface of the sections, and b) a toe bar mounted on the form.

63. The form for constructing a thrower's circle according to claim 62, wherein each of the plurality of structural sections comprises a plurality of side members and at least one cross member extending between the plurality of side members.

64. The form for constructing a thrower's circle as recited in claim 63, wherein each arcuate portion extends across the at least one cross member at least one location.

65. The form for constructing a thrower's circle according to claim 63, wherein each of the at least one cross member comprises a notch adapted to receive one of the plurality of arcuate portions.

66. The form for constructing a thrower's circle as recited in claim 62, comprising the plurality of tubes adjacent to the arcuate portions.

67. The form for constructing a thrower's circle as recited in claim 66, wherein each of the plurality of tubes is positioned to drain water from the thrower's circle.

68. The form for constructing a thrower's circle as recited in claim 62, comprising the toe bar mounted on the form.

69. The form for constructing a thrower's circle as recited in claim 68, wherein the toe bar is mounted to at least one of the arcuate portions of the form.

70. The form for constructing a thrower's circle as recited in claim 62, wherein the full circle comprises an upper edge disposed at a height greater then a height of an upper surface of the plurality of structural sections.

71. The form for constructing a thrower's circle as recited in claim 62, wherein the plurality of structural sections comprises two structural sections.

72. The form for constructing a thrower's circle as recited in claim 71, wherein each of the two structural sections comprises four right angled corners.

73. The form for constructing a thrower's circle according to claim 72, further comprising braces positioned in each of the four right angled corners.

74. The form for constructing a thrower's circle as recited in claim 62, wherein the plurality of arcuate portions comprises two arcuate portions.

75. The form for constructing a thrower's circle as recited in claim 74, wherein the two arcuate portions comprise semi-circles.

76. The form for constructing a thrower's circle as recited in claim 62, further comprising a plurality of nuts and bolts for securing the plurality of structure sections together.