JP2007289763A - Air pump for soft tennis ball - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air pump by which smooth inserting of an inserting rod into a rubber valve of a soft tennis ball is performed and durability of sealing effect of the rubber valve is obtained. <P>SOLUTION: The air pump for a soft tennis ball is equipped with an inserting rod 8 which has a hole part 8a for air discharging on the tip end part to be inserted into a rubber valve of the soft tennis ball, a pump member 6 assembled on the rear end part of the inserting rod 8, a cap member 9 into which the inserting rod 8 is removably inserted and which is removed when air is injected, and a lubricant applied body 10 to be in contact with the outer periphery surface of the inserting rod 8. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a soft tennis ball and an air pump, and more particularly to a structure of a rubber valve for injecting air provided in the soft tennis ball for injecting air and an air pump suitably used for the rubber valve for injecting air. .

  As a rubber valve for air injection provided in a soft tennis ball for injecting air into the soft tennis ball, there is one with a check valve (Patent Document 1).

This check valve-equipped rubber valve is formed of an elongated hollow rod-like member, and a valve body into which an insertion rod for air injection in which a hole for projecting air is formed on the side surface of the tip is inserted, and the tip of the valve body A check valve portion covering the portion, and the check valve allows air protruding from the hole portion of the insertion rod passing through the valve body to be injected into the soft tennis ball. It plays the role of preventing the air in the ball from leaking outside through the valve body. Further, the valve body is formed with a very thin slit with a constant width along the axial direction in a columnar rubber member extending in and out.
JP 2001-170215 A

  An object of the present invention is to provide an air pump capable of smoothly inserting an insertion rod into a slit of a rubber valve and maintaining the sealing effect of the slit of the rubber valve.

  The configuration of an air pump for a soft tennis ball that realizes the object of the present invention is to inject air into a soft tennis ball in which a rubber valve for air injection having a slit formed through in the axial direction is fixed to the inner surface of the ball ball shell. A pneumatic tennis pump for a soft tennis ball, wherein an insertion rod having an air discharge hole formed at a tip portion inserted into the rubber valve, a pump member attached to a rear end portion of the insertion rod, and the insertion rod A cap member that is removably inserted and removed when the air is injected, and a lubricant application body that is provided in the cap member and that is coated with a lubricant and contacts the outer peripheral surface of the insertion rod. It is characterized by.

  According to the present invention, since the insertion rod for injecting air can be smoothly inserted into the rubber valve, the rubber valve is not damaged and the adhesiveness of the slit is not impaired. Therefore, the adhesiveness of the slit can be further improved.

  FIG. 1 is a cross-sectional view of an essential part showing an embodiment of a soft tennis ball pneumatic pump according to the present invention, and FIGS. 2 and 3 are soft tennis balls that can be filled with the soft tennis ball pneumatic pump shown in FIG. The principal part see-through | perspective view and sectional drawing are shown.

  First, in FIG. 2 and FIG. 3, the soft tennis ball 1 has a rubber valve 3 bonded and fixed with an adhesive so that the outer end faces a small hole 2 a formed in a part of the ball shell 2. 2 and 3, the rubber valve 3 is drawn large for easy understanding, and is actually small as shown in the dimensions described later.

  The rubber valve 3 has a projection 3a that engages with the small hole 2a of the ball spherical shell 2 at the center of the outer end portion, and a thin flange portion 3b is formed so as to continue to the base of the projection 3a. It consists of a solid rubber member in which a columnar valve body 3c is formed on the inner end side from the flange portion 3b, and is integrally molded to form a single structure. An adhesive is applied to the outer surface side of the thin flange portion 3b.

  Further, the valve body 3c is formed in a tapered shape in which the outer diameter gradually decreases from the outer end side toward the inner end side.

  Since the outer shape of the protrusion 3a is formed in a tapered shape in which the outer diameter gradually decreases toward the outer side, even if the inner diameter dimension of the small hole 2a formed in the ball spherical shell 2 varies, the taper portion is sufficient. It can be absorbed, and the inner edge of the small hole 2a can be adhered to the outer peripheral surface of the projection 3a without any gap, so that the inner edge of the small hole 2a does not turn up. In particular, if the inner edge of the small hole 2a is formed on a tapered surface that matches the outer diameter of the protrusion 3a, the inner edge of the small hole 2a can be prevented from turning up.

  The rubber valve 3 is formed with an introduction hole 3d which is a bottomed opening for introducing the insertion rod of the air pump in the center of the projection 3a, and is slit by a cutter (not shown) in accordance with the introduction hole 3d. 3e is formed to penetrate to the inner end surface 3f of the valve body 3c. The slit 3e is formed inside the bulb 3, and is not formed up to the outer periphery.

  The rubber valve 3 in the present embodiment has a total weight of 0.8 g as an upper limit value, and the compounding chemical resulting from vulcanization as a material is 2 parts by weight or less of an adhesive, 1 to 5 parts by weight of a softener, and a pigment. 2 parts by weight or less, powder filling is not used. The polymer is NR, IR, BR alone or a blend.

  Further, the rubber hardness of the valve 3 is set to 30 ± 5 ° and is set to 35 ° or less. The rubber hardness was measured using a durometer type A manufactured by Shimadzu Corporation.

  The thin flange portion 3b has a thickness of 0.3 to 0.8 mm, which greatly contributes to weight reduction.

  Further, the outer diameter of the valve body 3c is 5 to 10 mm for the large diameter portion, 3 to 8 mm for the small diameter portion, and the length of the rubber valve 3 is 5 to 11 mm.

  The slit 3e is formed with a width of 1.0 mm to 3.0 mm.

  Unlike a basketball with a hard ball shell, the ball ball shell is very soft, so a very large impact force is applied to the rubber valve in actual use, and the tennis racket may directly hit the rubber valve. Since it is required to endure such an impact so that there is no air leak, a rubber valve used for a hard ball ball shell such as basketball or volleyball cannot be applied as it is.

  To meet these requirements simply, for example, if the rubber valve is enlarged and the elasticity applied to the slit is increased to increase the adhesion to the slit, the air tightness can be maintained even if the air pressure in the soft tennis ball suddenly increases. It's possible. Also, if the rubber valve is too hard, high adhesion to the slit cannot be obtained, and confidentiality may be impaired.

  Furthermore, when the weight of the rubber valve increases, the overall balance of the soft tennis ball may be lost, and an unexpected hitting trajectory may occur.

  This rubber valve 3 is a solution to such a problem specific to soft tennis balls. The outer shape of the valve body 3c is tapered so that the outer shape gradually decreases from the outer end toward the inner end surface. As a result, the thickness on the inner end side becomes thinner, and the rigidity on the inner end side of the valve body 3c is lowered accordingly, and the adhesion of the slit 3e at the inner end portion is improved.

  Further, since the outer end side of the rubber valve 3 is thick, the rigidity is higher than that of the inner end side, and the rate of extreme deformation is small even when a large impact force is applied at the time of impact, and the valve body 3c is greatly deformed. On the other hand, the slit 3e is pushed with strong elasticity to close the slit 3e.

  Of course, the slit 3e is elastic and has adhesiveness over the entire length of the rubber valve 3 in the axial direction. However, especially when a soft tennis ball is hit, the rigidity on the outer end side having a large diameter is increased. By making it larger than the side, deformation is suppressed as much as possible to reduce air leakage, and at the same time, the inner end side, whose rigidity is smaller than that of the outer end side, is made flexible and easily deformable, so that it can function as a check valve. It helps to reduce leaks.

  Further, in the present embodiment, since the outer shape of the valve body 3c is a tapered shape, it contributes to the weight reduction of the rubber valve in combination with the thin flange portion 3b.

  Next, when the air in the soft tennis ball 1 is reduced, the insertion rod of the air pump is inserted into the introduction hole 3d of the rubber valve 3 to widen the slit 3e. Insert until protruding from the inner end 3f.

  At this time, the ball ball shell 2 of the soft tennis ball 1 is soft and the friction between the rubber valve 3 and the insertion rod of the air pump is large. Therefore, the rubber valve 3 is picked up so that the ball ball shell 2 is applied, and The insertion rod must be strongly inserted into the slit 3e of the rubber valve 3. For this reason, it is conceivable that the slit 3e is easily damaged, and sufficient adhesion cannot be obtained. Further, if the rubber valve 3 is strongly picked, the ball ball shell 2 applied to the rubber bulb 3 may be damaged.

  Next, a soft tennis ball pneumatic pump according to the present invention will be described below with reference to FIG.

  In the pneumatic pump 5 of the present embodiment, a rod-shaped insertion rod 8 is attached to the distal end portion of a hollow pump member 6 formed in a spherical shape by a rubber member. A pair of air discharge holes 8a are formed to face each other.

  Further, a threaded portion 7 is formed at the root portion where the insertion rod 8 is attached to the pump member 6, and a cap member 9 covering the insertion rod 8 is screwed to the threaded portion 7. The pump member 6 has a hole (not shown) for taking in air at the rear end portion. When injecting air, the pump member 6 is pushed and deformed by pressing the hole with the belly of the thumb, for example. The air in 6 can be injected into the soft tennis ball 1.

  In the present embodiment, a lubricant application body 10 such as a sponge coated with a lubricant such as silicon oil is provided on the inner surface of the cap member 9, and when the cap member 9 is attached to the insertion rod 8, the lubricant The lubricant of the application body 10 is always applied to the insertion rod 8.

  For this reason, when the cap member 9 is removed from the air pump 5 and the insertion rod 8 is inserted into the rubber valve 3, it is inserted into the slit 3e of the rubber valve 3 so as to slide due to the lubricating action of the lubricant applied to the outer surface of the insertion rod 8. Thus, the hole 8 a penetrates the inner end surface 3 f of the rubber valve 3 and enters the ball spherical shell 2.

  As described above, when the air is pumped into the soft tennis ball 1 of the first embodiment using the air pump 5 of the second embodiment, the insertion rod 8e can be smoothly inserted into the slit 3e of the rubber valve 3. As a result, the insertion rod 8 can be completely inserted into the rubber valve 3 while the soft tennis ball 1 is lightly held in the hand.

  For this reason, air can be introduced without performing a method of strongly picking the rubber bulb 3 that easily damages the ball spherical shell 2, and the slit 3e of the rubber bulb 3 is not damaged, so that the adhesion of the slit 3e is maintained. The

  Further, after the insertion rod 8 is pulled out, a part of the lubricant applied to the insertion rod is applied to the inner peripheral surface of the slit 3e, so that the adhesion of the slit 3e becomes higher.

  In the present embodiment, the insertion rod 8 is plated on the outer peripheral surface, the diameter is 0.8 to 1.2 mm, the length is 13 mm to 20 mm, and when inserted into the rubber valve 3 as described above, It is sufficient that the hole 8a has a length that reliably penetrates the inner end surface 3f of the valve 3.

The principal part sectional view showing one embodiment of the air pump for soft tennis balls by the present invention. The principal part perspective view of the soft tennis ball which can put air with the air pump for soft tennis balls shown in FIG. Sectional drawing of the rubber valve of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Soft tennis ball 2 Ball spherical shell 3 Rubber valve 3a Protrusion part 3b Flange part 3c Valve body 3d Introduction hole 3e Slit 3f Inner end surface 5 Inlet pump 6 Pump member 7 Screw part 8 Insertion rod 8a Hole part 9 Cap member 10 Lubricant application body

Claims (1)

A soft tennis ball inflating pump for injecting air into a soft tennis ball in which a rubber valve for air injection having a slit formed in an axial direction is fixed to the inner surface of the ball spherical shell,
An insertion rod in which a hole for air discharge is formed at a tip portion inserted into the rubber valve, a pump member attached to a rear end portion of the insertion rod, and the insertion rod are detachably inserted, and the air injection A soft tennis ball pneumatic pump comprising: a cap member that is removed at the time of the operation; and a lubricant application body that is provided in the cap member, is coated with a lubricant, and contacts the outer peripheral surface of the insertion rod. .