JP2012139295A - Method for adjusting tension of net rope in athletic net, and assisting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for adjusting the tension of a net rope such that the tension becomes a preset proper prescribed tension in an athletic net used for volleyball or the like, and to provide an assisting device for the adjustment.SOLUTION: A condition is set with a position of the central part upper edge of the net set to be a prescribed height (H) as a first position (PO), and with a position to which the upper edge descends and stops when imparting a downward prescribed load (F) to the upper edge from a state that the net rope actually holds a prescribed tension (N) as a second position (P). In the tension adjustment of the net rope, the prescribed load (F) is imparted to the upper edge in a state where the rope holds the prescribed height (H) by a standard tension (T), it is decided whether descent positions (PL), (PH) of the upper edge having descended thereby is above or below the second position (P), and the tension is added/reduced to/from the net rope such that the descent positions (PL), (PH) of the upper edge approach the second position (P).

Description

The present invention provides a method of adjusting the tension of a net rope so as to be appropriate and a support device for the adjustment of a net for a game used in volleyball and other net games.

In net competitions such as volleyball and tennis, a net rope that suspends the competition net is bridged between the poles, and the height from the ground to the upper edge of the center of the net is the predetermined height stipulated in the competition rules. As you can see, the net rope is tensioned.

JP 2000-153010 A JP-A-8-191910

For example, in the case of volleyball, for example, in the case of volleyball, the net height is 2m43cm for boys and girls for ordinary people and university students, 2m40cm for boys 2m20cm for high school students, 2m30cm for girls 2m15cm for junior high school students, and 2m for boys and girls for elementary school students As stated above, there are no official agreements regarding the net tension at present.

For this reason, when the net is stretched, the net rope is tensioned by applying a reference tension, and the upper edge of the net central portion is adjusted to be the height of the coat standard.

However, net ropes (including steel stranded wires and polymer stranded wires) pull the net to a predetermined height by tensioning, but the top edge of the net is in a straight horizontal state. Therefore, there is a risk that an excessive tension is applied to cause an accidental breakage of the net rope or the support column is bent.

By the way, the competition net is held at the predetermined height by giving the net rope a predetermined tension or more, but if the net rope tension is increased from that state, the height of the net does not change, Net rope repulsion changes. Therefore, in the net competition, since the opposite competitors compete under the same net conditions, there is no unfairness among the competitors due to differences in the net conditions for each game. Since the rebound of the ball changes the rebound of the ball, and the skill of the player skillfully affects the handling of such a rebound, it is desirable to keep the net rope tension constant throughout the game.

The present invention provides a net rope tension adjusting method and support device for a competition net that solves the above-mentioned problems. According to the present invention, the net rope tension raises the height of the net to a predetermined height. It is necessary and sufficient for this purpose, but there is no risk of cutting the net rope, and the predetermined tension is set to have a predetermined repulsive force that makes the ball bounce uniform, and the net is stretched during the competition. Each time it is installed, the net rope tension can be adjusted to a predetermined tension with a simple operation.

Therefore, the net rope tension adjusting method of the present invention is configured as a means to hang a net rope that suspends a competition net between struts, and the height from the ground to the upper edge of the net central portion. Apply a standard tension (T) to the net rope so that it becomes the predetermined height (H) specified in the competition rules, and then tension the net rope so that the net rope tension becomes the predetermined tension (N). The position of the upper edge of the net center at the predetermined height (H) is defined as a first position (P0), and the net rope actually holds the predetermined tension (N). After setting the condition that the position of the upper edge that descends and stops when a predetermined downward load (F) is applied to the upper edge is the second position (P), the net rope sets the above-mentioned standard tension (T). Loaded processing that applies the specified load (F) to the upper edge of the net center while holding A determination step for determining whether the lowering position (PL) (PH) of the upper edge of the net center in the load applying step is higher or lower than the second position (P); and On the basis of this, there is a tension adjustment step of applying tension to the net rope or reducing the tension so that the descending position (PL) (PH) of the upper edge is close to the second position (P).

Further, the net rope tension adjustment support device of the present invention is configured as a means comprising a lower member that can stand upright from the ground, an upper member that extends upward from the lower member, and a competition net. Locking means provided on the upper member so that it can be locked to the upper edge of the upper member, and the upper member is moved so that the locking means descends from a predetermined height (H) determined by a competition rule. Elevating means for freely raising and lowering, load adding means for allowing a load to be applied to the upper member so that the upper member descends with a predetermined load (F), and provided between the lower member and the upper member The gauge means locks the locking means to the upper edge of the central portion of the net, and the upper edge is in the no-load state in which no downward load is applied to the upper edge. The first display hand indicating whether or not it is located at the first position (P0) that is the height (H) The net rope has a predetermined tension (N) in a load state in which the predetermined load (F) is applied to the upper member by the load applying means while the step and the locking means are locked to the upper edge of the center of the net. The second display means showing the second position (P) where the upper edge of the net lowers and stops when holding the net, and the upper edge of the net central actually lowers in the load state. A third display means for indicating a difference between the stopped lowered position (PL) (PH) and the second position (P) is provided.

In a preferred embodiment of the apparatus according to the present invention, the upper member is slidably inserted into the lower member and includes a window portion that allows the surface of the lower member to be seen through, and an indicator means facing the window portion. Yes. The lower member is provided with the first display means at a portion that enters the window portion in the unloaded state, and is provided with second display means that enters the window portion in the loaded state, and the third means by the indicator means. Display means are configured.

The upper member is provided with level display means slidable in the vertical direction along the side of the window, and the indicator means is provided on the level display means.

Preferably, an indicating unit indicating an allowable range of the vertical position of the first display unit or the second display unit that has entered the window portion is provided, and the indicating unit is provided above and below the indicator unit.

The upper member is preferably provided with a level slidable in the vertical direction, and the load applying means is preferably constituted by a weight detachably attached to the upper member.

According to the present invention, it is possible to adjust the tension of the net rope so as to be the predetermined tension N that has been set by simple work each time the net is stretched during a competition, and thereby the net is stretched. It is possible to prevent an accidental break of the net rope at the time, and it is possible to have a fair competition in which the ball bounce does not change every competition.

It is a perspective view explaining the net used for the volleyball game as an example of a net game exemplarily. The method of this invention is demonstrated, (A) is a front view which shows the method of setting conditions with a sample net, (B) is a net rope when the method of this invention is implemented in the net stretched by the standard tension | tensile_strength. FIG. 6C is a front view when it is determined that the tension of the net rope is lower than the set tension, and FIG. It is a front view at the time of determining. It is a perspective view which shows one Embodiment of this invention apparatus in an exploded state. It is a perspective view which shows one Embodiment of this invention apparatus in an assembly state. (A) is the sectional view on the AA line of FIG. 4, (B) The sectional view on the BB line of FIG. 4, (C) is a front view which shows a level display means. It is a perspective view which shows the use condition of this invention apparatus, and shows with the net | network made into the no-load state. It is a perspective view which shows the use condition of this invention apparatus, and shows with the net | network made into the load state. The state which implemented this invention method by this invention apparatus is shown, (A) is a front view which shows the state of a gauge means when a net is made into a no-load state, (B) is when a net is made into a load state FIG. 6C is a front view showing the state of the gauge means when it is determined that the net rope tension is lower than the set tension, and FIG. 8C is determined that the net rope tension is higher than the set tension when the net is loaded. It is a front view which shows the state of the gauge means in the case of being done. It is sectional drawing which shows another embodiment of this invention apparatus.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 exemplarily shows a net used in a volleyball game as an example of a net game. In the net 1, a net rope 3 is inserted into a bag-like band 2 fixed to an upper edge portion, and an auxiliary rope 5 is inserted to a bag-like band 4 fixed to a lower edge portion. When the net 1 is stretched, the net rope 3 is bridged between the struts 6 and 6 and is given a tension T as a guideline. The net 1 is pulled up until the height to the upper edge (hereinafter referred to as the central upper edge S) reaches a predetermined height H defined by the competition rules.

When the net rope 3 is tensioned, the winch 7 as shown in the figure may or may not be used, but the net rope 3 is in a state where the central upper edge S of the net 1 is pulled up to a predetermined height H. The target tension T is maintained. The auxiliary rope 5 is connected to the support 6 below the net 1.

The net rope 3 is adjusted so that the tension becomes the set tension N by the method of the present invention and the device of the present invention in a state where the net 1 is pulled up with the reference tension T. In the case of a net for volleyball, it is necessary and sufficient to raise the height of the net 1 to a predetermined height H defined in the court standard, but there is no risk of cutting the net rope 3, and the ball rebounds uniformly. It is preferable to set to a set tension N (Newton) capable of providing a predetermined repulsive force.

Therefore, although the method and the device of the present invention will be described below with respect to a volleyball net, the present invention can of course be applied to a net in a net game other than volleyball, and the set tension N is set according to the net conditions. It should be understood that the present invention can be applied to various net competition nets by appropriately changing the apparatus according to the following configuration.

(Method of the present invention)
FIG. 2 shows that the principle of the method of the invention can be implemented. FIG. 2A shows a sample net 1a for setting conditions prior to implementing the present invention. The sample net 1a holds the tension of the net rope 3 at a predetermined tension N preset by a tension measuring instrument, and holds the central upper edge S at the predetermined height H. The height of the central upper edge S The position in the direction is defined as a first position P0. Therefore, when a predetermined downward load F is applied to the central upper edge S from this state, the central upper edge S descends from the first position P0 and stops due to the bending of the net rope 3, so that the stop position is Measured as two positions P and acquired as a set condition (condition setting step). The predetermined load F is obtained, for example, by hanging a weight having a predetermined weight on the hook metal fitting in a state where the hook metal fitting is suspended by being engaged with the central upper edge S. For example, if a weight of 10 kg is used, the predetermined load F is 10 kg. As a result, the second position P is measured to acquire data, which is used as a condition for carrying out the subsequent method of the present invention. The second position P can be measured by a measure or the like as a specific numerical value as a height distance from the ground to the second position P or a height distance from the first position P0 to the second position P. it can.

FIG. 2B shows an example in which the method of the present invention is applied to a case where the net rope 3 is tensioned by the reference tension T but is lower than the predetermined tension N with respect to the net 1 actually stretched. Is shown.

The net 1 is positioned at the first position P0 where the center upper edge S is set to the predetermined height H even if the tension T is a reference. From this state, the above-described predetermined load F is applied to the center upper edge S. (The load adding step), the central upper edge S is lowered and stopped by the distance M1, so that the lowering stop position is measured as the lowering position PL and compared with the second position P obtained in the condition setting step. It is determined whether the position PL is higher or lower than the second position P (determination step).

In the example of FIG. 2B, the lowering position PL is positioned lower than the second position P as indicated by the distance −L, and it is determined that the reference tension T is lower than the predetermined tension N. From this state, a new tension N + is applied to the net rope 3 so as to raise the central upper edge S to a position close to the second position P (tension adjusting step). As a result, the net rope 3 maintains the predetermined tension N, and thus the method of the present invention is terminated.

FIG. 2 (C) shows an example in which the method of the present invention is applied to the case where the net rope 3 is tensioned by the reference tension T but is higher than the predetermined tension N with respect to the net 1 actually stretched. Is shown.

The net 1 is positioned at the first position P0 where the center upper edge S is set to the predetermined height H even if the tension T is a reference. From this state, the above-described predetermined load F is applied to the center upper edge S. (The load adding step), the central upper edge S is lowered and stopped by the distance M2, so that the lowering stop position is measured as the lowering position PH and compared with the second position P obtained in the condition setting step. It is determined whether the position PH is higher or lower than the second position P (determination step).

In the example of FIG. 2C, the lowering position PH is positioned higher than the second position P as indicated by the distance + L, and it is determined that the reference tension T is higher than the predetermined tension N. From the state, the tension of the net rope 3 is reduced as indicated by N− so as to lower the central upper edge S to a position close to the second position P (tension adjusting step). As a result, the net rope 3 maintains the predetermined tension N, and thus the method of the present invention is terminated.

In either case of FIG. 2 (B) and FIG. 2 (C), the first position P0, the second position P, the lowered positions PL and PH can be measured by a measure or the like. This can be done by using the same weight as in the condition setting step.

(Invention device)
3 to 8 show an embodiment of the device of the present invention. The apparatus includes a lower support 10 as a lower member that can stand upright in the vertical direction from the ground, an upper support 11 as an upper member that extends upward from the lower support 10, and a central upper edge S of the competition net 1. The locking means 12 formed of a hook or the like provided on the upper support 11 and the locking means 12 can be locked to the center upper edge S having a predetermined height H. Lifting means for raising and lowering the upper strut 11 and lowering it from the raised position, and a load for allowing a load to be applied to the upper strut 11 so that the upper strut 11 descends with a predetermined load F The additional means 13 and the gauge means 14 provided between the lower strut 10 and the upper strut 11 are configured.

The lower support column 10 is only required to be able to stand on the ground, but a pedestal 15 is provided at the lower end so that the lower support column 10 can stably stand on its own. The lower support column 10 and the upper support column 11 are formed of a pipe material having an oval cross section, and the upper support column 11 is slidably extrapolated from above the lower support column 10 as shown in FIG. The elevating means is constituted by the above.

As shown in FIG. 5, with the upper column 11 slidably fitted on the lower column 10, the upper and lower columns 11, 10 are oblong in cross section and cannot be rotated with each other. Overlapping flat plate portions 11a and 10a having a predetermined width W are provided, and the flat plate portion 11a of the upper support column 11 is formed with a window portion 16 that allows the flat plate portion 10a of the lower support column 10 to be visually recognized from the outside. In the case of the illustrated example, the window portion 16 is formed by a window hole opening, but a transparent plate may be provided. In addition, it is preferable to form the rib or groove | channel for improving sliding on the sliding surface of the up-and-down support | pillars 11 and 10 in a longitudinal direction.

As shown in FIG. 3, the gauge means 14 includes a fixed-side gauge means 14 a provided on the lower support column 10 and a moving-side gauge means 14 b provided facing the window 16 of the upper support column 11. ing.

The fixed-side gauge means 14a constitutes the first display means 17 for displaying the first position P0 and the second display means 18 for displaying the second position P, and these display means 17, 18 is provided on the flat plate portion 10 a of the lower support column 10. As described above, there are a plurality of types of volleyball, such as ordinary people, university students, high school students, junior high school students, and the like, with different predetermined heights H of the net depending on the athlete. Accordingly, the display means 17 and 18 may be provided so as to correspond to at least one type of athlete, but in the case of the illustrated embodiment, the display means 17a corresponding to the predetermined height H of the first type athlete is provided. The display means 17b and 17c corresponding to the predetermined height H of 18a and the 2nd type player are arranged up and down, and it is comprised so that it can respond to multiple types with one apparatus. The display means may be additionally arranged so as to correspond to the predetermined height H of three or more types of athletes.

The display means 17, 18 is configured so that the upper support 11, which is extrapolated to the lower support 10, slides upward, and the locking means 12 is locked to the central upper edge S of the net. Is in a no-load state at a position of a predetermined height H, the first display means 17 enters the window portion 16, and from this state, a predetermined load F is applied, and a load state in which the central upper edge S is lowered. The second display means 18 is sometimes arranged so as to enter the window portion 16. In other words, in order to enable such an arrangement relationship, the distance from the lower end grounding surface of the lower support column 10 to the display means 17, 18 and the locking surface of the locking means 12 of the upper support column 11 to the window portion 16. The distance is determined. At this time, it is desirable that the height position of the window portion 16 at the time of use is set to be within the range of the line of sight of an operator having a normal height while making the arrangement relationship possible. In the present specification, “locking” between the locking means 12 and the central upper edge S is limited to a configuration in which the hook-shaped locking means 12 is hooked on the central upper edge S as shown in the figure. It is meant to include a configuration in which the substantially horizontal locking means 12 is brought into contact with the central upper edge S. In short, the height H of the central upper edge S of the net 1 can be detected. The center upper edge S can be urged downward when a predetermined load F is applied.

The moving-side gauge means 14b is constituted by the third display means 19 facing the window portion 16 of the upper column 11, and in the case of the illustrated embodiment, it is slidable in the vertical direction along the side portion of the window portion 16. The level display means 20 is configured by providing an indicator means 21 composed of an arrow mark or the like.

As shown in FIGS. 5 (A) and 5 (B), the level display means 20 is constituted by a flexible member that holds the upper column 11 having an oval cross section with both ends facing both side edges of the window portion 16. In addition, it is slidable by being elastically contacted with the outer surface of the upper support 11, but it is self-fixable at a free position. As shown in FIG. Instruction means 22a and 22b indicating the permissible range R indicated by “−00N”, “+ 00N” or the like are provided. The level display means 20 is provided above the slidable level display means 20 by providing the display 21a and 21b on the upper support 11 as shown by the arrow marks in FIG. It is preferable to indicate an appropriate position. The vertical dimension of the level display means 20 functions as an indication 1H and 1L indicating an acceptable tolerance Q related to a predetermined height H of the net 1 as will be described later. The indication indicating the tolerance Q is the indication means. You may substitute by 22a, 22b or display 21a, 21b.

The load adding means 13 is composed of an upper support 11 having its own weight and at least one or a plurality of (two in the illustrated embodiment) weights 23, and the weight 23 is attached to and detached from the upper support 11. Support means 24 made of a flange-shaped disk that can be freely provided is provided in the vicinity of the lower end of the upper support 11. In the case of the illustrated example, the weight 23 is provided with a concave groove 23a that can be fitted on the outer peripheral surface of the upper column 11 having an oval cross section, and a concave portion 23b that allows the support means 24 to be fitted on the lower surface. In addition, a convex portion 23c that can be fitted into the concave portion 23b is formed on the upper surface. Therefore, the weight 23 is detachably mounted by fitting the upper support 11 into the groove 23a. At this time, the weight 23 is slidable up and down. However, the groove 23a holds the outer surface of the upper support 11 so that the weight 23 cannot be rotated, and when the weight 23 is lowered, the support means 24 is inserted into the recess 23b. Is attached so that it cannot be removed. When the plurality of weights 23 are stacked, the convex portion 23c of the lower weight 23 is fitted and integrated into the concave portion 23b of the upper weight 23, and the upper weight 23 is also mounted so as not to fall off. In addition, in order to facilitate attachment / detachment work of the weight 23, finger hook portions 23d are provided on both sides of the weight 23.

In the case of the illustrated embodiment, a level 26 is provided on the upper column 11 via a bracket 25 that is slidable in the vertical direction, located below the window 16. As shown in FIG. 5B, the bracket 25 is composed of a flexible member that holds the upper support 11 having an oval cross section, and slides by being elastically contacted with the outer surface of the upper support 11. Although it is free, it is self-fixable in a free position, and a level 26 made of a bubble level is provided on the flange 25a of the bracket 25. Therefore, when the device is erected on the ground (floor surface), it is possible to confirm whether or not the upper and lower columns 11 and 10 are along the vertical line by observing the level 26. In addition, by sliding the bracket 25 up and down, the level 26 can be moved to an easy-to-see position for the operator.

A procedure for carrying out the method of the present invention by the device of the present invention will be described with reference to FIGS. First, as shown in FIG. 6, the pedestal 15 is grounded, the vertical posture of the upper and lower columns 11, 10 is confirmed by the level 26, and then the upper column 11 is extended upward, whereby the above-described reference tension T Thus, the locking means 12 is locked to the central upper edge S of the net 1 having a predetermined height H, and the upper support 11 is held by the operator at that position. Therefore, in this state, the central upper edge S of the net 1 is in an unloaded state.

As shown in FIG. 8A, when the locking means 12 is locked to the central upper edge S, the first display means 17 enters the window 16 and appears. When the center upper edge S of the net 1 is accurately positioned at a predetermined height H and the level display means 20 is set to an appropriate position for the displays 21a and 21b, the first display means 17 is an indicator means as shown in the figure. Since it agrees with 21, the next work is advanced as it is.

When the first display means 17 does not match the index means 21, the net 1 is not set to the predetermined height H. However, when the tolerance Q is acceptable, it is determined that the operation can be continued, and the level display means 20 The indicator means 21 is made to coincide with the first display means 17 by sliding and the next operation is advanced.

If the first display means 17 is at a position outside the range of the tolerance Q, the height of the central upper edge S of the net 1 is not recognized, so that the tension of the net rope 3 is increased or decreased. Thus, after adjusting to the predetermined height H, the above operation is performed again.

Therefore, when the weight 19 is mounted and the upper support 11 is released from the operator's holding as shown in FIG. 7 with the index means 21 aligned with the first display 17, the weight of the upper support 11 and the weight Since the predetermined load F by the total weight of 19 is given, the central upper edge S of the net 1 bends downward via the locking means 12 to be in a loaded state, and the upper support 11 is lowered accordingly, As shown in FIGS. 8B and 8C, the second display means 18 enters the window 16 and appears. When the tension of the net rope 3 is the predetermined tension N, the second display means 18 matches the indicator means 21, but when the tension of the net rope 3 is lower than the predetermined tension N, FIG. As shown in FIG. 8C, the second display means 18 appears above the index means 21. Conversely, when the tension of the net rope 3 is higher than the predetermined tension N, the second display means 18 is shown in FIG. Appears below the indicator means 21.

When it is determined that the tension of the net rope 3 is insufficient as shown in FIG. 8B, the central upper edge S is raised by increasing the tension of the net rope 3 in this state. When the indicator means 21 comes close to the second display means 18 as the upper support 11 is raised, it is determined that the net rope 3 has maintained the predetermined tension N, and the operation is finished.

Conversely, when it is determined that the tension of the net rope 3 is excessive as shown in FIG. 8C, the central upper edge S is lowered by decreasing the tension of the net rope 3 in this state, and the upper support 11 When the indicator means 21 comes close to the second display means 18 along with the lowering of the position, it is determined that the net rope 3 has maintained the predetermined tension N, and the operation is finished.

When the permissible range is recognized for the predetermined tension N of the net rope 3, it is not necessary to adjust the tension of the net rope 3 until the indicator means 21 matches the second display means 18, and the second display means 18 indicates the indication means 22a, If it is within the allowable range R indicated by 22b, it can be determined that there is no problem in the competition.

(Another embodiment)
In the above embodiment, the load adding means 13 is configured by the weight 23. However, the load adding means 13 can be configured by the spring 27 as shown in FIG.

In the case of another embodiment shown in FIG. 9, a spring 27 is interposed between the lower strut 10 constituting the lower member and the upper strut 11 constituting the upper member, and the spring 27 faces downward with respect to the upper strut 11. The predetermined load F can be applied.

The lower strut 10 is provided with a driving means 28 such as a winch, and is provided with an engaging / disengaging means 29 that raises the upper strut 11 against the spring 27 and that can be stopped at a predetermined lifting position.

Therefore, according to this embodiment, the upper support 11 is lifted by the driving means 28, and the upper support 11 is moved by the engagement / disengagement means 29 at the position where the locking means 12 such as a hook is locked to the central upper edge S of the net. If stopped, it can be confirmed whether or not the net 1 in an unloaded state has a predetermined height H through the gauge means 14a and 14b similar to the above-described embodiment.

Therefore, when the engagement / disengagement means 29 is released, the upper support 11 is urged by the spring 27 and is brought into a load state in which a predetermined load F is applied to the central upper edge S of the net. Then, the excess or deficiency of the tension of the net rope 3 may be determined via the gauge means 14a and 14b, and the tension of the net rope 3 may be increased or decreased so as to be the predetermined tension N.

(Configuration of the present invention)
Of course, the present invention is not limited to the above-described embodiment, and the upper support 11 may be lifted and the predetermined load F may be applied by using, for example, an electric motor or other power. Further, the determination of the net height H by the gauge means 14a, 14b, the determination of the excess or deficiency of the tension of the net rope 3 when the predetermined load F is applied, and whether the tension is adjusted to the predetermined tension N after increasing or decreasing the tension. The determination or the like may be configured so that it can be automatically determined by providing a magnetic or electrical sensor or the like on the gauges 14a and 14b in addition to the visual observation by the operator as in the above embodiment.

DESCRIPTION OF SYMBOLS 1 Net 3 Net rope 10 Lower support | pillar 11 Upper support | pillar 12 Locking means 13 Load adding means 14a Fixed-side gauge means 14b Moving-side gauge means 16 Window 17 First display means 18 Second display means 19 Third display means 20 Level display means 21 Index means 22a, 22b Instruction means 23 Weight 24 Support means 26 Level

Claims (7)

The net rope that suspends the competition net is bridged between the poles, and the height from the ground to the upper edge of the center of the net is the predetermined height (H) defined by the competition rules. Is a method of adjusting the tension so that the net rope tension becomes a predetermined tension (N)
The position of the upper edge of the center of the net at the predetermined height (H) is defined as the first position (P0), and the net rope actually holds the predetermined tension (N), and the predetermined value downwards toward the upper edge. After setting the condition that the position of the upper edge that descends and stops when the load (F) is applied is the second position (P),
A load applying step of applying the predetermined load (F) to the upper edge of the center of the net in a state where the net rope holds the reference tension (T);
A determination step of determining whether the lowering position (PL) (PH) of the upper edge of the net central portion in the load applying step is higher or lower than the second position (P);
Based on the determination, a tension adjustment step of applying tension to the net rope or reducing the tension so that the lowered position (PL) (PH) of the upper edge is close to the second position (P);
A net rope tension adjusting method for a competition net, comprising: A lower member (10) that can stand upright from the ground, an upper member (11) that extends upward from the lower member, and an upper edge (S) of the competition net so that it can be locked. Locking means (12) provided on the upper member, and elevating and lowering the upper member (11) so that the locking means is lowered from a predetermined height (H) determined by a competition rule. Provided between the lower member and the upper member, and a load adding means (13) capable of applying a load to the upper member so that the upper member (11) is lowered with a predetermined load (F). Gauge means (14a) (14b),
The gauge means locks the locking means (12) to the upper edge (S) of the center of the net, and the upper edge is in the no-load state in which no downward load is applied to the upper edge. First display means (17) indicating whether or not it is located at the first position (P0) defined as (H);
The locking means (12) is locked to the upper edge (S) of the center of the net, and in the load state where the predetermined load (F) is applied to the upper member (11) by the load adding means (13). A second display means (18) for indicating a second position (P) where the upper edge (S) of the center of the net descends and stops when the net rope holds a predetermined tension (N), and the load And a third display means (19) showing the difference between the lowered position (PL) (PH) and the second position (P) where the upper edge (S) of the net center actually descends and stops in the state. A net rope tension adjustment support device for a competition net. The upper member (11) is slidably extrapolated to the lower member (10), and includes a window portion (16) that allows the surface of the lower member to be seen through, and index means (21) facing the window portion. Provided,
The lower member (10) is provided with the first display means (17) at a portion entering the window portion (16) in the unloaded state, and the second display means entering the window portion (16) in the loaded state. (18)
3. The net rope tension adjustment support device for a game net according to claim 2, wherein said index means (21) constitutes said third display means (19). Level display means (20) slidable in the vertical direction along the side of the window (16) of the upper member (11) is provided, and the indicator means (21) is provided on the level display means. The net rope tension adjustment support device for a competition net according to claim 3. Indicating means (22a) and (22b) indicating the allowable range (R) of the upper and lower positions of the first display means (17) or the second display means (18) entering the window (16) are provided on the indicator means (21). The net rope tension adjustment support device for a game net according to claim 3 or 4, wherein the net rope tension adjustment support device is provided vertically. 6. A net rope tension adjustment support in a competition net according to claim 2, wherein the upper member (11) is provided with a level (26) slidable in the vertical direction. apparatus. The said load addition means (13) is comprised by the weight (23) which can be attached or detached with respect to an upper member (11), The net | game for competitions of Claim 2, 3, 4, 5 or 6 characterized by the above-mentioned. Net rope tension adjustment support device.

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