Pole device for skiing contest

Abstract: A pole device for a skiing contest comprises a cylindrical member (1) to be embedded in a snow ground, a pole base member (5) to be fitted into the cylindrical member and a pole portion (3) fitted into the pole base member. The pole base member is formed with grooves extending in an axial direction thereof on an outer peripheral surface thereof and the cylindrical member is formed with projections at an inner peripheral surface thereof. Each of the projections has an outer shape to be fitted in the groove. The groove is composed of a first guide groove (13) having an end portion through which the projection enters the groove, a second guide groove (17) formed to be continuous to the first guide groove through a circumferintially shifted groove portion and a circumferential fitting groove (19) formed at a portion near upper end of the pole base member to be continuous to the second guide groove. A pair of grooves are formed on the outer peripheral surface of the pole base member in an axial symmetrical arrangement and a pair of projections (1a,1b) are formed on the inner peripheral surface of the cylindrical member in an axial symmetrical arrangement. A triangular guide piece (15) is formed to an edge portion of each of the circumferentially shifted groove portions so as to project inward thereof.

Description: The present invention relates to a pole device used for example as a flag gate for a skiing contest such as an uphill turn and the like. Well known is a pole device for the skiing contest having a cylindrical portion to be embedded in snow on the ground and a base portion of a pole member to be fitted into the cylindrical portion to thereby stand up the pole member on the snow surface. In use of the pole device of the known type, there is a case that the pole member is broken or snapped during the skiing contests, and for this reason, it is desired to easily draw out the pole member from the cylindrical portion embedded in the snow for easily and quickly exchanging the broken pole member with new one. On the contrary, it is also desired that the pole member is not easily drawn out without manual operation because the easy draw-out of the pole member during the skiing contest is dangerous for players and the exchanging working is also troublesome. As described above, it is desired for the pole device to have functions which are mutually conflicted from each other, and in order to satisfy these conflicting functions, in the prior art, there is provided a pole device having a cylindrical portion formed with a female threaded portion on the inner peripheral surface thereof and having a pole base portion formed with a male threaded portion on the outer peripheral surface to be engaged with the female threaded portion. However, in this pole device, there is a problem that the pole base portion can be rotated by repeated colliding of contestants or players with the pole device so that the pole portion can be unintentionally knocked out of the cylindrical portion embedded in the snow. US-A-2859840 discloses a support for a sign post in which two projections on a post are fitted into a base having an axially extending groove leading into a circumferentially extending groove for each respective projection. This structure also suffers from the above mentioned problem. An object of the present invention is to provide a pole device in which a pole cannot be unintentionally knocked out of a cylindrical portion embedded in snowy ground during the skiing contest, but which can be easily drawn out manually when necessary. According to the present invention, there is provided a pole device for a skiing contest, comprising a cylindrical member to be embedded in snowy ground, the cylindrical member having inner hollow portion; and a pole base member to be fitted into the inner hollow portion of the cylindrical member; characterised by a pole portion fitted into the pole base member and, in use, standing upwards on the snowy ground when the pole base member is fitted to the cylindrical member embedded in the snowy ground; wherein the pole base member is formed on its outer surface with a generally axially extending groove means, and the cylindrical member is formed with a projection projecting from an inner peripheral surface of an open end of the inner hollow portion, the projection being shaped to be fitted into a first end of the groove means; the groove means being composed of a first guide groove extending axially from the first end portion, a second guide groove formed to be continuous to the first guide groove, with a guide piece projecting into the groove means between the first and second guide grooves and the groove means being provided with a radially offset portion adjacent to the guide piece so that as the projection passes from the first to second guide grooves the pole base member undergoes some rotational movement relatively to the cylindrical member; and a circumferential groove formed remote from the first end of the pole base member so as to be continuous with the second guide groove, the circumferential groove being provided with opposed axially projecting projections which extend from opposing side walls of the circumferential groove and are spaced apart by an axial distance greater than the axial length of the projection, and the second guide groove extending into the circumferential groove through the adjacent axially projecting projection. Preferably a pair of the groove means are formed on the outer peripheral surface of the pole base member in an axially symmetrical arrangement, and a pair of the projections are formed at corresponding positions on the inner peripheral surface of the cylindrical member in an axially symmetrical arrangement. Preferably the or each guide piece is triangular, and presents an inclined surface towards the first end of the groove means to tend, in use, to cause relative rotation of the pole base member with respect to the cylindrical member. Preferably the pole base member has a frustoconical end portion to be first fitted into the cylindrical member and a cylindrical portion continuous with the frustoconical end portion, in which the groove and offset portion are formed. Preferably the cylindrical member is formed on its outer peripheral surface with a helical projection. In this case, the helical projection may have cutout portions at which projection pieces are formed. In the accompanying drawings: Fig. 1 is a front view, partially in section, of one embodiment of a pole device for skiing contest according to the present invention; Fig. 2 is a front view of a pole base member of the pole device of Fig. l; Fig. 3 is a sectional view taken along the line III-III of Fig. 2; Fig. 4 is a sectional view taken along the line IV-IV of Fig. 2; Fig. 5 is a front view of a top portion of a cylindrical member of the pole device of Fig. 1; and Fig. 6 is a top plan view of the cylindrical member as viewed from an arrowed direction VI in Fig. 5. A pole device adapted for skiing contests according to the present invention comprises, as shown in Fig. 1, a cylindrical member 1 which is to be embedded in snow ground and a pole base member 5 into which a pole 3 is fitted. Referring to Fig. 1, the cylindrical member 1 is formed with a spiral projection 1a on its outer peripheral surface, and this spiral projection 1a acts as a screw when the cylindrical member 1 is forcibly embedded in the snow and also attains a draw-out preventing function after the cylindrical member 1 has been once embedded in the snow. In order to facilitate these functions, in the illustration, the spiral projection 1a has cutout portions and a plurality of projected pieces 1b each having a shape different from the spiral form of the projection 1a are formed on the cutout portions of the spiral projection 1a, but the formation of such projected pieces 1b is optional. The cylindrical member 1 has an inner hollow portion in which the pole base member 5 is fitted. In this condition, the pole 3 is fitted into an inner hollow portion of the pole base member 5 through a known spring means so that the pole 3 stands upward from the pole base member 5 through the spring means. Of course, the pole 3 may be preliminarily fitted into the pole base member 5 before the fitting into the cylindrical member 1. According to the location of the spring means, the pole 3 is flexibly bent bilaterally when a contentant collides with the pole 3 during the skiing contest. According to the structure of the pole device of the present invention, the pole base member 5 can be easily fitted into and drawn out from the inner hollow portion of the cylindrical member 1 when an operator intends to fit the pole base member 5 into the cylindrical member 1 or to draw out the same therefrom, but the pole base member 5 cannot easily be drawn out from the cylindrical member 1 when the pole base member 5 is unintentionally drawn out from the cylindrical member 1. Namely, as shown in Figs. 2 to 4, the pole base member 5 has lower and upper ends 5a and 5b and is composed of substantially a cylindrical portion 5c and a frustconical front end portion 5d. Of course, the pole base member 5 may be formed to have cylindrical shape entirely in the axial direction without forming the frustconical end portion. A groove 11 is formed to an outer peripheral surface of the pole base member 5. The groove 11 is opened at the lower end 5a of the front end portion 5d and is composed of first and second guide grooves 13 and 17. The first guide groove 13 extends upward in an axial direction of the pole base member 5 from the lower end 5a of the pole base member 5 and the first guide groove 13 is formed with a circumferentially shifted groove portion 13a formed to the cylindrical portion 5c of the pole base member 5. The second guide groove 17 is formed to be continuous to the shifted groove portion 13a and extends upwards in the axial direction of the pole base member 5. A guide piece 15 having substantially a triangular shape is formed to the pole base member 5 so as to project at an edge portion of the circumferentially shifted groove portion 13a between the first and second guide grooves 13 and 17. That is, the guide piece 15 projects inward of the circumferentially shifted groove portion 13a. As shown in Fig. 2, the triangular guide piece 15 has a upward tapered lower portion. The second guide groove 17 is continuous to a fitting groove 19, which extends in the circumferential direction of the pole base member 5. The fitting groove 19 is formed along the entire outer peripheral surface of the pole base member 5 at a portion near the upper end 5b thereof. The fitting groove 19 has upper and lower edges 19a and 19b to which projections 21 and 23 are formed so as to project inwardly of the fitting groove 19. In a preferred embodiment, though not shown, another groove substantially the same structure of the groove 11 is formed to the pole base member 5 on the side opposing to the groove 11 in approximately axially symmetrical manner. Next, referring to Figs. 5 and 6, a pair of projections 25, 25 are formed to the inner peripheral surface of the cylindrical member 1, at upper end portion thereof, in an axially symmetrical arrangement so as to be engaged with the grooves 11 of the pole base member 5 when fitted. The projection 25 has a width w which is slightly smaller than each of widths W of the first and second guide grooves 13 and 17. The projection 25 enters the groove 11 from the opened lower end of the first guide groove 13, when fitted, and the pole base member 5 is further deeply fitted into the inner hollow portion of the cylindrical member 1 by depressing the same downward, the projections 25 advance upward through the first guide groove 13, the second guide groove 17 and then the circumferential fitting groove 19 on the upper end side 5b of the pole base member 5. The pole device according to the present invention of the structure described above is set in use in the following manner. The cylindrical member 1 is first embedded in the snow. At this time, a certain jig, not shown, is fitted inside the cylindrical member 1 and the head of the jig is then struck by means of, for example, a hammer, or a handle means is fixed to the jig and the handle means is rotated to screw in the cylindrical member 1 into the snow. In the next step, the pole base member 5 fitted with the pole 3 is fitted into the cylindrical member 1 embedded in the snow. In this fitting operation, the opened end of the first guide groove 13 is mated with the projection 25 and the pole base member 5 is then depressed downward. It will be desired to mark a positioning marker to the end surfaces of the pole base member 5 and the cylindrical member 1 for easy visual fitting thereof. When the pole base member 5 with the pole 3 engaged is depressed, the projection 25 enters the groove 11 and advances in the first guide groove 13 upward along its axial direction. The projection 25 will then collide with the the tapered lower surface of the triangular projection 15 projecting inward of the first guide groove 13. Upon this collision, the guide piece 15 is forced by the projection 25 and rotated in the circumferential direction according to the tapered surface thereof, and the projection 25 goes over the guide piece 15 and further advances in the second guide groove 17 from the first guide groove 13. The projection 25 then advances between projections 21 and 23 formed to the circumferential fitting groove 19, and rotates the pole base member 5 in the circumferential direction. The projection 25, after the disengagement from the projections 21 and 23, is moved into the fitting groove 19 and finally firmly fitted therein. In this embodiment, as shown in Fig. 5, the projection 25 is formed so as to have an axial length l which is smaller than each of the axial lengths l₁ and l₂ formed on both axial sides of the guide piece 15 on the circumferentially shifted groove portion 13a of the first guide groove 13, and the length l of the projection 25 is also slightly smaller than a distance l₃ between the projections 21 and 23 of the fitting groove 19. According to the structures and characters of the pole device described above, the pole base member 5 with the pole 3 being fitted can be easily fitted manually into the cylindrical member 1 by abutting the opened end of the first guide groove 13 against the projection 25 and then depressing the pole base member 5. After the fitting of the pole base member 5 into the cylindrical member 1, when it is required to draw out the pole base member 5 manually by hands, the pole base member 5 is first lifted upward by the length corresponding to the height h of the projection 21 and then circumferentially rotated to move the projecting means 25 to a position between the projections 21 and 23. Thereafter, the projection 25 is positioned just above the second guide groove 17 and the pole base member 5 is further lifted upward, whereby the projection 25 enters the second guide groove 17 and then advances therein. Upon abutting against the guide piece 15, the pole base member 5 is rotated in one circumferential direction, and when the projection 25 goes over the guide piece 15, the pole base member 5 is then rotated in the opposing, i.e. reverse, circumferential direction. Accordingly, the projection 25 moves into the first guide groove 13. In this state, the projection is disengaged from the groove 11 by lifting upward the pole base member 5, and the pole base member is thus drawn out manually from the cylindrical member 1. Namely, in order to draw out the pole base member 5 from the cylindrical member 1, many manual operations such as lifting the pole base member 5 and rotating the same in one and opposite circumferential directions are required. Accordingly, it is substantially impossible that these operations are accidentally carried out even by repeated collision of the skiing contestants or players with the pole 3 during the skiing contest, so that the pole base member 5 cannot be draw out unintentionally from the cylindrical member 1 by the pole device according to the described embodiment of the present invention. As described hereinbefore, according to the pole device for the skiing contest of the present invention, the pole base member cannot substantially be drawn out unintentionally from the cylindrical member embedded in the snow, but it can be easily drawn out intentionally therefrom, thus such conflicting functions being easily attained, which are substantially impossible in the prior art pole device.

Claims: A pole device for a skiing contest, comprising a cylindrical member (1) to be embedded in snowy ground, the cylindrical member having inner hollow portion; and a pole base member (5) to be fitted into the inner hollow portion of the cylindrical member; characterised by a pole portion (3) fitted into the pole base member and, in use, standing upward on the snowy ground when the pole base member is fitted to the cylindrical member embedded in the snowy ground, wherein the pole base member (5) is formed on its outer surface with a generally axially extending groove means (11), and the cylindrical member (1) is formed with a projection (25) projecting from an inner peripheral surface of an open end of the inner hollow portion, the projection being shaped to be fitted into a first end of the groove means (11); the groove means (11) being composed of a first guide groove (13) extending axially from the first end portion, a second guide groove (17) formed to be continuous to the first guide groove, with a guide piece (15) projecting into the groove means (11) between the first (13) and second (17) guide grooves and the groove means (11) being provided with a radially offset portion (13a) adjacent to the guide piece (15) so that as the projection (25) passes from the first to second guide grooves the pole base member undergoes some rotational movement relatively to the cylindrical member; and a circumferential groove (19) formed remote from the first end of the pole base member so as to be continuous with the second guide groove, the circumferential groove being provided with opposed axially projecting projections (21,23) which extend from opposing side walls of the circumferential groove and are spaced apart by an axial distance greater than the axial length of the projection (25), and the second guide groove (17) extending into the circumferential groove (19) through the adjacent axially projecting projection (23). A pole device according to claim 1, wherein a pair of the groove means (11) are formed on the outer peripheral surface of the pole base member (5) in an axially symmetrical arrangement, and a pair of the projections (25) are formed at corresponding positions on the inner peripheral surface of the cylindrical member (1) in an axially symmetrical arrangement. A pole device according to claim 1 or claim 2, wherein the or each guide piece (15) is triangular, and present an inclined surface towards the first end of the groove means (11) to tend, in use, to cause relative rotation of the pole base member (5) with respect to the cylindrical member (1). A pole device according to any one of the preceding claims, wherein the pole base member (5) has a frustoconical end portion (5d) to be first fitted into the cylindrical member (1) and a cylindrical portion (5c) continuous with the frustoconical end portion, in which the groove (11) and offset portion (13a) are formed. A pole device according to any one of the preceding claims, wherein the cylindrical member (1) is formed on its outer peripheral surface with a helical projection (1a). A pole device according to claim 5, wherein the helical projection (1a) has cutout portions at which projection pieces (1b) are formed.

Inventors: KATO KOJI, SHIMURA KIYOSHI, KATO, KOJI, SHIMURA, KIYOSHI, Kato, Koji, c/o K &amp; K Kogyo Kabushiki Kaisha, Shimura, Kiyoshi, c/o K &amp; K Kogyo Kabushiki Kaisha
Applicants: K & K KOGYO KABUSHIKI KAISHA
Application year: 1993
Main classification: A63C19
IPC codes: A63C19, A63C11