JP2006130145A - Device for polishing pachinko ball - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact polishing device, while keeping a high polishing ability. <P>SOLUTION: A lifting means 1 lifts the game balls upward, which are collected from each pachinko game machine in an island with the pachinko game machines arranged therein. Then, the pachinko ball is polished by a polishing member, while being guided by a helical groove and lowered by a lowering polishing means 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a ball polishing machine installed in a pachinko gaming machine installation island.

  <About polishing equipment>

  In pachinko halls where pachinko machines are installed, multiple pachinko machines are installed so that they face each other. A ball polishing and lifting device having both a function and a lifting function has been disposed between the lower supply tank and the upper supply tank.

  Conventionally, there are two types of game ball polishing and lifting devices that lift and polish game balls such as pachinko balls from the lower part to the upper part of Pachinko Island.

  The first is a pellet type (polishing fluid). This is a game ball and abrasives taken from a lower intake into a pipe-shaped transfer cylinder, stirred and lifted and polished inside the tube by a rotating spiral, and discharged from the upper part of the device, And a polishing material are separated by a saw blade and circulated.

  The second is a cloth type (nonwoven fabric polishing method). This is equipped with a driving roller at the bottom of a standing frame and a driven roller at the top, and an endless ring-shaped lifting belt is hung between both rollers, and the roller is rotated to rotate around the feeding belt. Then, a belt-like polishing cloth is temporarily provided on the opposite surface of the lifting belt, and a game ball is sandwiched between the lifting belt and the polishing cloth and is ground by rotating the gaming ball.

  However, each polishing and lifting apparatus has the following problems.

  In the pellet type, since the abrasive and polishing debris cannot be reliably separated from the pachinko balls, they are mixed into the ball circulation path to impede the function of the pachinko machine, and sometimes wear parts. In addition, it was necessary to perform a cleaning operation periodically in order to remove dirt from the abrasive. Further, since the abrasive also wears, it has been necessary to periodically replace the entire surface. In addition to this, there are inconveniences such as noise during polishing, a large installation space on the island, and a heavy weight of the polishing machine body.

  Further, in the cloth type, in order to prevent the polishing performance from being deteriorated due to dirt on the polishing cloth, there is a trouble of setting the cloth every day. Furthermore, when installed on the island, a large space and weight were involved as in the pellet type.

  Therefore, both systems require a considerable amount of labor to attach and detach the polishing / lifting device to the amusement island during installation, loading and maintenance.

  <About cloth type polishing equipment>

  As described above, there is a cloth-type polishing apparatus as a pachinko ball polishing apparatus (for example, Patent Document 1). This means that a belt conveyor (lifting belt) that lifts pachinko balls from the lower part to the upper part and an abrasive cloth are opposed to each other, and the belt conveyor lifts the pachinko balls while rubbing the pachinko balls against the cloth. The pachinko ball was polished. This polishing device also serves as a lifting device that lifts pachinko balls from the lower part to the upper part of the pachinko island. For this reason, the previous belt conveyor and the abrasive extend from the lower part to the upper part of the pachinko island.

However, in the conventional polishing apparatus, since it is necessary to arrange the belt conveyor and the abrasive that serve as the ball polishing means and the lifting means from the lower part to the upper part of the pachinko island, a relatively thick square material containing them is the pachinko island. It has become a factor that hinders the space saving of Pachinko Island, such as a space that can not install a pachinko stand. In addition, since the polishing apparatus is installed from the bottom to the top of Pachinko Island, it takes time to install and remove the polishing apparatus, and the polishing apparatus itself can be easily removed during maintenance. Since it was not possible, it was necessary to perform maintenance while it was installed on Pachinko Island, and the work was difficult. Moreover, since the apparatus is large, transportation was not easy.
Japanese Patent Laid-Open No. 2001-9142

  The object of the present invention is to improve the disadvantages of the conventional example, and in particular to provide a compact polishing apparatus while maintaining a high polishing ability.

  In order to solve the above-mentioned problems, the present invention is to lift the balls collected from each pachinko machine on the island where the pachinko machine is installed, and then polish the pachinko balls with a polishing member while being guided by a spiral groove and lowered. A pachinko ball polishing apparatus is provided. The polishing apparatus includes a main body base installed on a floor surface, an outer cylinder suspended from the main body base, and a central shaft that is coaxially and rotatably disposed in the outer cylinder. Further, there are provided a rotation driving means for rotating the central shaft body and a spiral groove formed on the outer peripheral surface of the central shaft body for guiding the pachinko ball in a partially exposed state. Further, a polishing member that is detachably disposed on the inner peripheral surface of the outer cylindrical body so as to face the spiral groove and that contacts and polishes the pachinko ball exposed from the spiral groove, and an introduction for introducing the pachinko ball into the spiral groove Means. Among these, the polishing member is composed of a base substrate having or taking a curvature corresponding to the curvature of the cylindrical surface to be mounted, and a polishing material provided on the polishing surface side.

  The means for lifting the balls collected from the pachinko machine is as a means for holding the balls between the endless belt and the polishing cloth and performing the lifting and polishing while rolling the balls upward by the rotation of the endless belt. Also good.

  Or the means which lifts the ball | bowl collect | recovered from the pachinko machine upward is good also as a structure which scoops up a ball | bowl from a lower intake with a belt with an endless profile.

  In the above polishing apparatus, a ball guide passage having a foreign matter removing function may be disposed between the means for lifting the ball upward and the central shaft body provided with the spiral groove.

  Further, the central shaft body may have a structure that can be easily detached from the rotational driving means.

  In addition, the outer cylinder is provided with a slit hole along the central axis of the outer cylinder, and after inserting a sheet-like polishing member into the slit hole, an uninserted portion of the polishing member is fixed to the outer cylinder. It is good also as a structure which provided the latching | locking part for the outer surface of the said outer cylinder.

  Or it is good also as a structure which provided the convex part by which the polishing member is latched in the inner surface of the outer cylinder.

  In addition, the base substrate of the polishing member may be made of synthetic resin and may be a planar or cylindrical integral molded product.

  Further, the polishing material constituting the polishing member may be formed of a nonwoven fabric.

  The polishing material may be configured by implanting fibers so as to form a storage space for storing the wiped pachinko ball deposits.

  Moreover, you may comprise an introduction means in the following form. That is, (a) the starting point of each spiral groove is arranged near the rotation axis of the central shaft body or in the vicinity of the rotation axis, and (b) each spiral groove is continuous from the rotation shaft or the vicinity of the rotation axis to the circumference of the central shaft body. (C) the direction vector of each spiral groove is in the form of changing from the rotation axis or the vicinity of the rotation axis in the radial direction and continuously changing the direction to the direction of contact with the circumference of the central shaft body. is there.

  Further, as a structure capable of obtaining the same effect as the present invention, a structure in which the central shaft body is fixed and the outer cylinder body is relatively rotated can be considered. Moreover, the structure which provides a spiral groove in the inner surface of an outer cylinder, and arrange | positions an abrasive on the surface of a center axis | shaft body can be considered. That is,

  This is a pachinko ball lifting and polishing device that lifts the balls collected from each pachinko machine on the island where the pachinko machine is installed, and then polishes the pachinko balls with a polishing member while being guided by a spiral groove and lowered. A main body base installed on the floor, an outer cylindrical body suspended from the main body base, a central shaft body coaxially disposed in the outer cylindrical body, and the outer cylindrical body and the central shaft body A rotational drive means for rotationally driving any one of the above, a spiral groove that guides the pachinko ball formed on the opposing cylindrical surface of either the outer cylindrical body or the central shaft body in a partially exposed state, A polishing member that contacts and polishes a pachinko ball exposed from a spiral groove that is detachably mounted on the other opposed cylindrical surface, and an introduction means that introduces the pachinko ball into the spiral groove disposed on the main body base. And the polishing member is adapted to the curvature of the cylindrical surface to be mounted. It pumped polishing apparatus pachinko ball, wherein the base substrate, that is composed of a polishing material formed on the polished surface having a curvature was.

  According to the present invention, since the polishing path is provided in a spiral shape, the polishing apparatus can be made compact while maintaining the polishing ability.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 4.

  <Device structure>

  In FIG. 1, the polishing apparatus of the present invention includes an ascending polishing means 1 for polishing while raising a pachinko ball from the lower part to the upper part, and a descent for polishing while descending the pachinko ball conveyed by the ascending polishing means. And polishing means 2. Further, a relay passage (ball guide passage) 5 for guiding the pachinko balls coming out from the outlet 3 at the upper part of the upward polishing means to the inlet 4 of the downward polishing means at the upper part of the downward polishing means is provided.

  In this embodiment, the ascending polishing means 1 is a downsized conventional cloth polishing type polishing apparatus. The cloth polishing type polishing apparatus includes a belt conveyor that rotates in the vertical direction of the apparatus, and the belt conveyor lifts the pachinko balls from the lower part to the upper part. A pachinko ball is rubbed between the facing cloth abrasives, whereby the pachinko ball is lifted and simultaneously polished. The size of the belt is reduced by shortening the feeding route by the belt conveyor. Reference numeral 6 denotes an intake port through which the upward polishing means takes in the pachinko balls from the outside.

  On the other hand, the downward polishing means 2 is provided with a spiral path (described later with reference to FIG. 2) in the vertical direction, and simultaneously performs polishing while lowering the pachinko balls along the spiral path.

  The polishing structure is as shown in FIG. First, a columnar rotating body (center shaft body) 7 is provided upright in the center. Then, the spiral groove 8 from the upper part to the lower part is provided as the spiral passage along the circumference of the cylindrical rotating body. The depth of the spiral groove is such that the pachinko ball is a circumferential surface of the rotating body 7. Set to protrude more outward. And the sheet-like abrasive | polishing material (abrasive member) 9a, 9b is arrange | positioned so that the outer periphery of this columnar rotary body may be enclosed. The abrasive surrounding the rotating body 7 does not contact the rotating body 7 and does not hinder the rotation of the rotating body, but contacts the pachinko balls protruding from the spiral groove and polishes the pachinko balls. Therefore, the abrasive surrounding the rotating body 7 is arranged with a slight gap between the rotating body. The polishing members 9a and 9b are positioned along an outer cylindrical body 11 (an outer shell indicated by reference numeral 2 in FIG. 1) surrounding the rotating body. Reference numeral 16 denotes an exit of the pachinko ball polished by the descending polishing means 2.

  Next, the structure in which the pachinko balls entering the down-polishing means 2 are guided from the relay passage 5 in FIG. 1 to the entrance of the spiral groove 8 becomes a problem. First, a plurality of spiral grooves 8 are provided, and the number of entrances to the spiral grooves is increased in proportion to the number of spiral grooves, thereby improving the probability that pachinko balls will enter the spiral grooves. This is realized by providing spiral grooves having the same shape with a phase shifted in the circumferential direction of the rotating body 7.

  In addition, the shape (introduction means) of the upper surface of the rotating body has been devised so that the pachinko balls that have entered the down-polishing means 2 from the relay passage 5 can be easily guided to the respective spiral grooves 8, as shown in FIG. The starting point of each spiral groove 8 is made to coincide with the rotating shaft 12 located at the center of the rotating body 7. Each spiral groove 8 is smoothly connected from the rotating shaft 12 at the center of the rotating body to the circumference of the rotating body, and the direction vector of each spiral groove 8 exits from the rotating shaft 12 at the center of the rotating body in the radial direction. The direction is smoothly changed to the direction in contact with the circumference of the rotating body. For this reason, the upper surface of the rotating body looks like a propeller at first glance, but a part of each spiral groove 8 exists between each fin that looks like this propeller. The tip of each fin is sharpened so as to be thin, and is devised so as not to play balls as much as possible.

  In this embodiment, the driving of the rotating body 7 and the driving of the belt conveyor in the ascending polishing means 1 are performed by using the same motor (rotation driving means 13) as a driving source and transmitting the rotation of this motor to a gear having a predetermined structure. Thus, the driving force is transmitted to the belt conveyor of the upward polishing means and the rotating body of the downward polishing means.

  <Installation structure>

  A plurality of ball-shaped casters 15 are fixed to the main body base 14 and arranged so that the balls protrude from the floor surface. At the time of movement, this ball rotates and functions as a caster. However, when the ball fits in a recess provided in advance in the floor portion of the pachinko island, the main body base 14 is positioned and fixed in the pachinko island. Therefore, the polishing apparatus is positioned and fixed with one touch. When removing the polishing apparatus from the pachinko island, the ball may be released from the recess provided on the pachinko island floor. As a result, the ball functions as a caster and can be easily detached from Pachinko Island.

  <Material of rotating body>

  As a material of the rotating body 7, for example, nylon can be adopted. It is a lightweight, wear-resistant material with excellent impact resistance.

  <About the structure and material of abrasives>

  The abrasive is composed of a base substrate 9a that is a base of the abrasive material and an abrasive material 9b that covers one surface of the base substrate. The base substrate 9a of the abrasive is made of synthetic resin, and is preferably a flat or cylindrical integrally molded product. In the case of a cylindrical shape, it matches the curvature of the outer cylinder 11. Further, the polishing material 9b constituting the polishing member is preferably made of a non-woven fabric, and is formed by implanting fibers so as to form a storage space for storing wiped pachinko ball deposits.

  That is, the abrasive material is made of a wear-resistant resin in the form of a fiber, and the fiber has a non-woven structure. With this structure, it is devised so that the polished dirt is accumulated inside and the time until replacement can be lengthened. Here, the polishing material alone has flexibility, and the flexibility makes it difficult to perform replacement work. Therefore, the polishing material is attached to a base substrate of polypropylene resin for the purpose of providing synthesis.

  <Positioning of abrasive>

  Two types of structures are considered when the abrasive is installed on the outer cylinder.

  First, as shown in FIG. 3, the outer cylinder 11 is provided with a slit hole 17 along the central axis of the outer cylinder, and after inserting a sheet-like abrasive member into the slit hole, the abrasive member This is a configuration in which a locking portion for fixing the non-inserted portion to the outer cylinder 11 is provided on the outer surface of the outer cylinder. The locking portion is configured by a locking convex guide 18 provided on the outer cylinder 11 along the slit hole 17 and an engaging pin protruding from a contact surface of the locking convex guide 18 with the polishing member. The engaging pin 19 is inserted into the hole provided at the L-shaped end of the polishing member, whereby the polishing member is fixed and positioned. That is, the state changes from (A) to (B) to (C) in FIG.

  Secondly, as shown in FIG. 4, a convex portion 21 to which the polishing member is locked is provided on the inner surface of the outer cylindrical body 11. When a polishing member composed of the base substrate 9a and the polishing material 9b is fitted into the outer cylinder 11 as shown in (A), the position of the cut of the polishing member and the convex portion 21 inside the outer cylinder coincide with each other. Adjust as follows. Thus, when the polishing member is fitted (B), the polishing material is locked against the outer cylinder 11, and the polishing material stops against the rotation of the central shaft body, thereby the pachinko ball polishing efficiency. Will improve. Here, if the polishing material 9b is provided longer than the base substrate 9a, the portion of the convex portion 21 can be covered with the polishing material 9b, so that the polishing gap can be filled.

  <Foreign matter removal function in relay passage>

  The relay passage 5 is provided with a foreign matter removing function. Screws, coffee and other various foreign substances flow into the relay passage 5. Some of these include player mischief. Therefore, a snowboard-like member that drops only foreign matter is laid in the relay passage. Foreign matter that has fallen from the relay passage through the slats falls through the foreign matter box to the floor of Pachinko Island and is collected during cleaning.

  <Removal of rotating body>

  The rotating body 7 has a structure that can be easily detached from the rotation driving means. The power of the motor, which is a driving means, rotates a rotating shaft located at the center of the rotating body via a predetermined gear. For example, a guide along the rotation axis is projected in the diameter direction of the rotation shaft, while a groove that fits the rotation shaft and the guide is formed from the bottom of the rotating body to the central axis. Then, the rotating body is placed over the rotating shaft with the position of the guide aligned, and the rotating shaft is inserted into the rotating body, whereby the rotating body is installed and positioned and fixed to the rotating shaft. On the contrary, if the rotating body is pulled upward with respect to the rotating shaft, the rotating body is detached from the rotating shaft. In this way, the rotating body can be installed and removed with one touch.

  <About equipment dimensions>

  Preferably, the vertical dimension of the polishing apparatus is set so as to be within the height of the waist plate of Pachinko Island. This facilitates the installation of the polishing apparatus in the pachinko island and the removal of the polishing apparatus from the pachinko island.

  <Operation of the device and the flow of pachinko balls>

  The pachinko balls used on the pachinko machine in the pachinko island are guided to the ball entrance 6 at the bottom of the ascending polishing means 1. Inside the ascending polishing means, the belt conveyor is rotated by a motor, and the pachinko balls that have entered the ascending polishing means from the ball entrance are transported to the upper part of the ascending polishing means by the belt conveyor. The primary polishing is performed by rubbing. The polished and lifted pachinko balls are discharged from the ball outlet 3 of the upward polishing means and enter the relay passage 5.

  The relay passage 5 is a rail having a U-shaped cross section, and is provided by spanning the arc-shaped rail from the outlet 3 of the ascending polishing means 1 to the entrance 4 of the descending polishing means 2. This arc-shaped rail is somewhat inclined like a mortar like a course of a bicycle race, and the inner circumference is lower than the outer circumference.

  Thereby, the pachinko balls spouted from the ascending polishing means quickly reach the entrance of the descending polishing means without killing the momentum.

  Inside the descending polishing means, the above-described rotating body 7 is rotationally driven by a motor. The rotation direction rotates in a direction in which the portion of the upper surface of the rotating body of the spiral groove 8 receives wind. When a pachinko ball that has passed through the relay passage 5 enters there, it falls on the propeller-like portion on the upper surface of the rotating body and contacts the portion of the spiral groove 8 on the upper surface of the rotating body. The pachinko balls that have come into contact with the spiral groove are pushed in the rotating direction of the rotating body as the rotating body 7 rotates, and receive a centrifugal force to roll the spiral groove 8 on the circumferential side of the rotating body 7. Each pachinko ball is guided to a portion of the spiral groove 8 formed in the circumferential portion of the rotating body. When the pachinko balls enter the circumferential portion of the rotating body 7, the pachinko balls are rubbed and polished between the polishing material 9b surrounding the rotating body and the spiral groove 8. At the same time, the pachinko balls fall along the spiral groove 8 to the lower part of the rotating body 7 (at this time, since the rotating body is rotating, the entire spiral groove is also rotating). The speed at which the pachinko ball falls through the spiral groove 8 to the lower part of the rotating body is affected by the frictional force applied to the pachinko ball, gravity, and the rotational speed of the rotating body. Therefore, by adjusting these, the polishing ability and the time required for polishing the pachinko balls are adjusted. The pachinko balls that have fallen to the lower part of the rotating body and have been polished are discharged from the outlet 16 of the descending polishing means.

  <Effects / features of this embodiment>

  This embodiment is a structure in which the polishing function and the lifting function are separated and independent, and the small and lightweight polishing apparatus can be stored in the waist plate portion of the pachinko game machine installation island, and maintenance of the polishing apparatus Even if detachment is required, detachment from Pachinko machine island can be done with one touch. In addition, since the lifting lift up to the upper part of the pachinko island can be specialized only for the lifting function, the lifting pipe can be set thin, and a structure that does not require a large space between pachinko machines can be realized.

  In addition, the polishing apparatus of this embodiment has a leap in polishing efficiency as a two-stage polishing structure of a first polishing unit (cloth polishing) and a second polishing unit (spiral polishing) connected to a single motor (driving means). Has been improved. And in order to greatly improve the polishing capability, a rotating body with a plurality of spiral grooves is arranged in the second polishing part to increase the polishing distance (polishing time), and at the same time realizes small size, light weight and low noise. .

  Furthermore, in order to make it easier to replace the worn abrasive material than before, to prevent the inflow of the abrasive material, and to eliminate the need for daily setting work of the polishing cloth, a completely new abrasive cartridge type is adopted. That is, it was devised to facilitate the removal and replacement of the polishing cartridge (the sheet of the polishing member) and to facilitate repair and replacement.

  In the present embodiment described above, ascending polishing means is provided as the pachinko ball lifting means. However, polishing in the lifting stage is not necessarily required, and instead of the ascending polishing means, the lifting function is omitted. Means may be employed.

  According to the present invention, since the polishing path is provided in a spiral shape, the polishing apparatus can be made compact while maintaining the polishing ability. For example, if the height of the polishing device is limited to the height of the waist plate of Pachinko Island, the pipe for lifting the pachinko ball to the upper part of Pachinko Island does not need to have a built-in polishing means. The cross-sectional area of the pipe can be reduced, and the space where the pachinko machine can not be installed is reduced, contributing to effective use of the space. In addition, the height of the polishing device is limited to the height of the waist plate of Pachinko Island, and the polishing device can be easily detached from Pachinko Island, making installation and removal work easier, thus making maintenance work easier. It becomes. In addition, since the polishing apparatus is configured in a compact manner, its transportation, loading and unloading can be facilitated.

1 is an overall perspective view of a polishing apparatus according to an embodiment of the present invention. It is a perspective view of the rotary body mounted in the grinding | polishing apparatus of FIG. It is explanatory drawing of the 1st structure which latches an abrasive member to an outer cylinder. It is explanatory drawing of the 2nd structure which latches an abrasive member to an outer cylinder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Up grinding | polishing means 2 Down grinding | polishing means 3 The ball | bowl exit of an up grinding | polishing means 4 The ball | bowl entrance 5 of a downward grinding | polishing means The relay path 6 The ball inlet 7 of an up grinding | polishing means Rotating body 8 Spiral groove 9a Base substrate 9b of abrasive | polishing material DESCRIPTION OF SYMBOLS 11 Outer cylinder 12 Rotating shaft 13 Drive means 14 Main body base 15 Caster 16 Ball exit 17 of descending polishing means Slit hole 18 Locking convex guide 19 Engaging pin 21 Convex part inside outer cylinder

Claims (11)

A pachinko ball polishing device that lifts the balls collected from each pachinko machine on the pachinko machine installation island, and then polishes the pachinko balls with a polishing member while guiding and lowering the pachinko balls with a spiral groove,
A main body base installed on the floor, an outer cylindrical body suspended from the main body base, a central shaft body coaxially and rotatably disposed in the outer cylindrical body, and the central shaft body being driven to rotate A rotation driving means for rotating, a spiral groove formed on the outer peripheral surface of the central shaft body for guiding the pachinko ball in a partially exposed state, and being attached to and detached from the inner peripheral surface of the outer cylindrical body facing the spiral groove A polishing member that is freely disposed and contacts and polishes the pachinko balls exposed from the spiral grooves, and an introducing means for introducing the pachinko balls into the spiral grooves,
A polishing apparatus for a pachinko ball, wherein the polishing member is composed of a base substrate that has or can take a curvature corresponding to the curvature of a cylindrical surface to be mounted, and a polishing material provided on the polishing surface side.   The means for lifting the balls collected from the pachinko machine is a means for sandwiching the balls between the endless belt and the polishing cloth and performing the lifting and polishing while rolling the balls upward by the rotation of the endless belt. The polishing apparatus according to claim 1, wherein:   2. The polishing apparatus according to claim 1, wherein the means for lifting the balls collected from the pachinko machine has a structure for scooping up the balls from the lower intake with a belt with an endless profile. The polishing apparatus according to claim 1, wherein
2. The polishing apparatus according to claim 1, wherein a ball guide passage having a foreign matter removing function is disposed between the means for lifting the ball upward and the central shaft body having the spiral groove.   The pachinko ball lifting and polishing apparatus according to claim 1, wherein the central shaft body has a structure that can be easily detached from the rotation driving means.   The outer cylinder is provided with a slit hole along the central axis of the outer cylinder, and after inserting the sheet-like polishing member into the slit hole, the uninserted portion of the polishing member is fixed to the outer cylinder. The polishing apparatus according to claim 1, wherein a locking portion is provided on an outer surface of the outer cylindrical body.   The polishing apparatus according to claim 1, wherein a convex portion on which the polishing member is locked is provided on an inner surface of the outer cylindrical body.   2. The polishing apparatus according to claim 1, wherein the base substrate of the polishing member is made of a synthetic resin and is a planar or cylindrical integral product.   The polishing apparatus according to claim 1, wherein the polishing material constituting the polishing member is made of a nonwoven fabric.   The polishing apparatus according to claim 1, wherein the polishing material is configured by implanting fibers so as to form a storage space for storing a wiped pachinko ball deposit. The polishing apparatus according to claim 1, wherein the introduction unit is configured as follows.
(a) The starting point of each of the spiral grooves is disposed in the vicinity of the rotation axis of the central shaft body or the rotation axis,
(b) Each spiral groove is continuously connected from the rotating shaft or the vicinity of the rotating shaft to the circumference of the central shaft body,
(c) A mode in which the direction vector of each spiral groove is changed in the direction continuously from the rotation axis or the vicinity of the rotation axis in the radial direction to the direction in contact with the circumference of the central shaft body.

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