Cue stick bumper, cue stick, method for installing a cue stick bumper, and method for removing a cue stick bumper

Abstract

To provide a cue stick bumper which can adjust the weight and center of gravity of the cue stick body more easily than before and can reduce the load on a press-fit portion, and also to provide a cue stick having the same, a method of attaching a cue stick bumper, and a method of removing a cue stick bumper.SOLUTION: A cue stick bumper 4 includes in an attachment hole 14 of a cue stick body 5: a weight screw 9 that can be screwed into the attachment hole; a press-fit portion 22 having the body of the weight screw 9 slidably provided in an insertion hole; and a bumper portion 23 which is separate from the press-fit portion 22 and fixed to the screw head of the weight screw 9.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a cue stick bumper, a cue stick, a method for attaching a cue stick bumper, and a method for removing a cue stick bumper. [Background technology]

[0002] A cue stick used in billiards can have its weight and center of gravity adjusted by attaching / detaching a weight of an optimum weight to the end of the cue stick body according to the player's preference or purpose.

[0003] For example, Patent Document 1 discloses that the end of the bat and the end of the shaft are joined with a joining member to form a cue stick body, and a screw-shaped weight for adjusting the weight balance is provided in a hollow hole of the bat. Patent Document 2 discloses that the weight balance is adjusted by removing a bumper attached to the end of the bat, inserting a tool into the hole, and appropriately tightening the weight to a desired position. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-287560 A [Patent Document 2] JP 2005-168934 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in Patent Document 1 and Patent Document 2, although the weight and center of gravity of the cue stick body can be adjusted using a screw-shaped weight, the hollow hole of the bat must be blocked with a bumper separate from the weight after the weight is placed in the hollow hole of the bat, so the attachment work to the cue stick body is cumbersome. Also, the bumper is pressed into the hollow hole and firmly fixed to the cue stick body. Therefore, for example, when replacing the weight with another one, the work of removing the single bumper pressed into the hollow hole from the hollow hole separately from the weight is also cumbersome. Therefore, there was a problem that the replacement work of the cue stick bumper was cumbersome and it was difficult to easily adjust the weight and center of gravity of the cue stick body.

[0006] In addition, although the bumper is firmly attached to the hollow hole, the press-fit portion of the bumper, which is the part that is pressed into the hollow hole, may be damaged if too much load is applied during installation or removal, and therefore it is desirable to be able to reduce the load on the press-fit portion.

[0007] The present invention has been made in consideration of the above points, and has as its object to provide a cue stick bumper, a cue stick equipped with the same, a method for attaching the cue stick bumper, and a method for removing the cue stick bumper, which enable adjustment of the weight and center of gravity of the cue stick body to be easier than before and also reduce the burden on the press-in portion. [Means for solving the problem]

[0008] The cue stick bumper of the present invention is a cue stick bumper that can be freely attached and detached to an attachment hole formed at the base end of a rod-shaped cue stick body that is used to strike a ball with its tip, and comprises a weight screw having a screw body that can be screwed into the attachment hole, a trunk portion connected to the screw body, and a screw head connected to the trunk portion, a cylindrical body in which the trunk portion is slidably arranged in an insertion hole, a press-in portion that is pressed into the attachment hole, and a bumper portion that is separate from the press-in portion and fixed to the screw head. Effect of the Invention

[0009] In the present invention, by providing the weight screw with a press-in portion and a bumper portion, the press-in portion and the bumper portion can be attached to or detached from the attachment hole together with the weight screw, which makes it easier to replace the bumper for the cue stick, and accordingly makes it easier to adjust the weight and center of gravity of the cue stick body than in the past. Also, when an external force of a certain level or more is applied from the body of the weight screw to the press-in portion, the body can slide within the insertion hole of the press-in portion, which makes it possible to prevent excessive external force from being applied to the press-in portion from the weight screw, and reduces the burden on the press-in portion. [Brief description of the drawings]

[0010] [Figure 1] 1 is an exploded view showing the configuration of a cue stick equipped with a cue stick bumper according to an embodiment of the present invention; [Diagram 2] 1 is a perspective view showing the configuration of a cue stick bumper as viewed from the screw body side. FIG. [Diagram 3] 2 is a perspective view showing the configuration of the cue stick bumper as viewed from the bumper portion side. FIG. [Figure 4] FIG. 2 is a vertical cross-sectional view showing a vertical cross-sectional configuration of a bumper for a cue stick. [Diagram 5] 1 is a perspective view showing a state in which a cue stick bumper is attached to a base end of a cue stick body using a tool. FIG. [Figure 6] 1 is a perspective view showing a state in which a cue stick bumper is attached to a bat. FIG. [Figure 7] 1 is a longitudinal sectional view showing a longitudinal sectional configuration of a cue stick bumper when attached to a base end of a cue stick body. FIG. [Figure 8] 1 is a longitudinal sectional view showing a cue stick bumper being removed from a base end of a cue stick body; FIG. [Figure 9] 1A to 1C are schematic diagrams showing variations of bumpers for cue sticks. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of a cue stick equipped with a cue stick bumper according to the present invention will be described. In the drawings used in this embodiment, the same components are denoted by the same reference numerals, and the description thereof will be partially omitted.

[0012] (1) Cue stick configuration Fig. 1 is an exploded view showing the configuration of a cue stick 1 according to this embodiment. As shown in Fig. 1, the cue stick 1 is composed of a rod-shaped cue stick body 5 with a tip 1a that strikes a ball, and a cue stick bumper 4 that is detachably attached to a base end 3b, which is the other end of the cue stick body 5. The cue stick body 5 is composed of a shaft 2 having a tip 1a that strikes a ball, and a bat 3 that is connected to the base end 1b of the shaft 2, and the cue stick bumper 4 is detachably attached to the base end 3b of the bat 3 (also referred to as the base end 3b of the cue stick body 5).

[0013] The cue stick 1 can be formed by coaxially connecting the shaft 2, butt 3, and cue stick bumper 4 together to form a single rod-shaped cue stick 1. In this embodiment, the side of the cue stick 1 where the shaft 2 is located is described as the tip side, and the side where the butt 3 is located is described as the base side.

[0014] The shaft 2 has a shaft body 15 made of a rod-shaped member, and a tap 7 is attached to the tip end of the shaft body 15 via a ferrule 8. The shaft 2 has a taper that continuously increases in diameter from the tip end 1a to the base end 1b. A pipe screw 16 is formed at the base end of the shaft body 15.

[0015] The shaft body 15 is manufactured by cutting a relatively hard wood such as maple. The material of the ferrule 8 is a relatively hard resin, such as PVC (Polyvinyl Chloride) resin or ABS (Acrylonitrile Butadiene Styrene) resin. The tip 7 is made of leather or synthetic resin, and is constructed of a single layer or laminated materials. The synthetic resin material of the tip 7 is, for example, phenolic resin or carbon fiber.

[0016] The pipe screw 16 is configured by forming a female screw groove 8a inside a hollow portion (not shown) that opens at the end of a shaft body 15.

[0017] The bat 3 has a bat body 10 which is a rod-shaped member having a thicker shaft than the shaft 2, a joint screw 17 attached to a tip end 3a of the bat body 10, and an attachment hole 14 formed in a base end 3b of the bat body 10. The bat body 10 is made by cutting or gluing together wood such as maple, ebony, and rosewood. The joint screw 17 is a screw member having a male screw groove 8b which screws into the female screw groove 8a of the shaft 2. The joint screw 17 is inserted into the pipe screw 16 of the shaft 2 and screws into the female screw groove 8a to connect the bat 3 to the shaft 2.

[0018] Butt body 10 has a taper that continuously expands in diameter from tip end 3a to base end 3b, and the taper is formed to be continuous with the taper of shaft 2. Therefore, cue stick body 5 formed by connecting shaft 2 and butt 3 becomes a single rod-shaped member that continuously expands in diameter from tip end 1a to base end 3b.

[0019] In this embodiment, a cue stick body 5 in which the shaft 2 and the butt 3 are detachably connected has been described; however, the present invention is not limited to this. For example, the shaft 2 and the butt 3 may be integrally formed from a single rod-shaped member, and a single cue stick body in which the shaft 2 and the butt 3 are not detachably connected may be applied.

[0020] Attachment hole 14 is drilled along the axial direction of bat body 10, and has opening 11 on the end surface of base end 3b of bat 3. The range in which attachment hole 14 is formed is shown as range r in Figure 1. It is preferable that the axial length of range r is longer than the length of threaded body 20 (described later) of cue stick bumper 4 that is attached to bat 3. The inner circumferential surface of attachment hole 14 has threaded region 12 where female thread groove 12a is formed, and non-threaded region 13 consisting of smooth non-threaded surface 13a where female thread groove 12a is not formed.

[0021] In this case, mounting hole 14 has non-threaded region 13 from opening 11 to a predetermined position within bat 3, and threaded region 12 from non-threaded region 13 to a predetermined position toward the center of bat 3. Cue stick bumper 4 is inserted and attached into mounting hole 14, spanning threaded region 12 and non-threaded region 13.

[0022] (2) Configuration of cue stick bumper Next, the configuration of the cue stick bumper 4 will be described. The cue stick bumper 4 has a weight screw 9 that can be screwed into the mounting hole 14, a press-fit portion 22 made of a cylindrical body provided on the weight screw 9, and a bumper portion 23 also provided on the weight screw 9. As shown in Fig. 1, the cue stick bumper 4 is inserted into the mounting hole 14 from the opening 11, and is inserted toward the mounting hole 14 (moves in the X direction in the figure) while the male screw groove 21 provided on the weight screw 9 is screwed into the female screw groove 12a of the threaded region 12 in the mounting hole 14. In Fig. 1, the X direction indicated by the arrow indicates the insertion direction in which the cue stick bumper 4 is inserted into the cue stick body 5. The -X direction indicated by the arrow indicates the direction in which the cue stick bumper 4 is pulled out of the cue stick body 5.

[0023] When attached to the cue stick body 5, the cue stick bumper 4 is attached to the base end 3b of the cue stick body 5 in a state in which the threaded body 20 and the press-fit portion 22 on the weight screw 9 are located inside the attachment hole 14, and the bumper portion 23 on the weight screw 9 is located outside the attachment hole 14. When the cue stick bumper 4 having the weight screw 9 of a predetermined weight is attached to the attachment hole 14, the weight of the cue stick bumper 4 is added to the cue stick 1, making it possible to adjust the weight of the entire cue stick 1 and to adjust the center of gravity (balance) of the cue stick 1.

[0024] Fig. 2 is a perspective view showing the configuration of the cue stick bumper 4 shown in Fig. 1 when viewed from the side of the threaded body 20. Fig. 3 is a perspective view showing the configuration of the cue stick bumper 4 when viewed from the side of the bumper portion 23. Fig. 4 is a vertical cross-sectional view showing the vertical cross-sectional configuration of the cue stick bumper 4. In Figs. 2 and 4, A indicates the rotation axis of the threaded body 20, and hereinafter the direction of the rotation axis of the threaded body 20 will be referred to as the "axial direction A".

[0025] The weight screw 9 is made of various metal members such as aluminum members or steel members that are heavier than aluminum members, and the weight of the cue stick bumper 4 can be adjusted to a predetermined value by changing the type of metal member and the length of the threaded body 20, which will be described later. As shown in Figures 2, 3, and 4, the weight screw 9 includes a threaded body 20, a body portion 40 connected to the threaded body 20, and a screw head portion 42 connected to the body portion 40. The threaded body 20 is formed in a cylindrical shape, and a male screw groove 21 that can be screwed into the mounting hole 14 is formed on the outer circumferential surface.

[0026] The body 40 is connected to the base end of the threaded body 20, and is provided between the threaded body 20 and the screw head 42. The body 40 does not have a male screw groove 21, and a press-fit portion 22 that is press-fitted into the mounting hole 14 is provided so as to be able to slide. The body 40 according to this embodiment has a plurality of portions with different diameters. The body 40 has a cylindrical connecting portion 45 that is connected to the threaded body 20, and a cylindrical expanded diameter portion 48 that has a larger diameter than the connecting portion 45, and the connecting portion 45 and the expanded diameter portion 48 are connected by a tapered portion 47.

[0027] The connecting portion 45 of the body 40 has one end connected to the threaded body 20 and the other end connected to an expanded diameter portion 48 via a tapered portion 47. The connecting portion 45 also has an annular protruding portion 24 that protrudes radially outward along the circumferential direction at a predetermined position on the outer circumferential surface. The protruding portion 24 is molded integrally with the connecting portion 45 and is formed from a metal member.

[0028] The protruding portion 24 according to this embodiment protrudes radially outward from the expanded diameter portion 48 connected to the connected portion 45. As shown in Fig. 4, when the outer diameter of the protruding portion 24 is R3 and the outer diameter of the expanded diameter portion 48 is R2, it is desirable that the outer diameter R3 of the protruding portion 24 is larger than the outer diameter R2 of the expanded diameter portion 48 (R3>R2).

[0029] The expanded diameter portion 48 has an outer circumferential surface that is smooth and free of irregularities, and is provided so that the outer circumferential surface can slide freely on the inner circumferential surface of the press-fit portion 22 of the cylindrical body. The expanded diameter portion 48 is integrally molded with the connecting portion 45 via a tapered portion 47 that gradually expands in diameter from the connecting portion 45, and is formed from a metal member.

[0030] The screw head 42 is integrally molded with the body 40 and is made of a metal member. The screw head 42 according to this embodiment has a screw head body 42a, an enlarged diameter end portion 26 provided at one end of the screw head body 42a, and an annular abutment portion 25 provided at the other end of the screw head body 42a. An engagement hole 36 that can be engaged with a mounting tool such as a hexagonal wrench is formed in the axial direction from the enlarged diameter end portion 26, the screw head body 42a, and the abutment portion 25.

[0031] In this case, the screw head body 42a is formed in a cylindrical shape, and an engagement hole 36 is drilled through the thickness from one end to the other end along the axial direction A. The abutment portion 25 is annular with the engagement hole 36 drilled in the center, and is integrally formed at one end of the screw head body 42a. The abutment portion 25 is selected to have an outer diameter larger than that of the screw head body 42a, and the outer peripheral surface is formed so as to protrude radially outward from the outer peripheral surface of the screw head body 42a. The abutment portion 25 is also selected to have an outer diameter larger than that of the expanded diameter portion 48 of the trunk 40, and the press-fit portion 22 provided on the trunk 40 abuts against the end face 25a on the side connected to the trunk 40, thereby positioning the press-fit portion 22.

[0032] The expanded diameter end 26 of the screw head 42 is annular with an engagement hole 36 drilled in the center, and is integrally formed with the other end of the screw head body 42a. The expanded diameter end 26 is selected to have an outer diameter larger than that of the screw head body 42a, and is formed so that its outer peripheral surface protrudes radially outward beyond the outer peripheral surface of the screw head body 42a. As a result, in the screw head 42, the screw head body 42a, which has a smaller diameter than the abutment portion 25 and the expanded diameter end 26, is disposed between the abutment portion 25 and the expanded diameter end 26, and a recess 25b is formed on the outer peripheral surface.

[0033] The press-fit portion 22 provided on the body 40 is made of an elastic material such as rubber, and is formed so as to be press-fitted into the inside of the mounting hole 14 from the opening 11 of the mounting hole 14 of the cue stick body 5. In this case, the press-fit portion 22 is a cylindrical body, and an insertion hole 22e is drilled through the thickness along the axial direction A. The press-fit portion 22 has one end 22b located on the side of the threaded body 20, and the other end 22c opposed to the end 22b and located on the side of the screw head 42, and has a tapered surface 22d with the corners cut along the outer periphery of the one end 22b.

[0034] In addition, the press-fit portion 22 has an outer diameter R4 that is equal to the inner diameter R5 (Figure 7) of the mounting hole 14 or is selected to be slightly larger than the inner diameter R5 of the mounting hole 14 (R4 ≧ R5), and is configured so that it can be press-fitted into the inside of the mounting hole 14 against the elastic force of the press-fit portion 22.

[0035] In addition, the press-fit portion 22 is configured so that the inner diameter R1 of the insertion hole 22e is equal to or slightly smaller than the outer diameter R2 of the body portion 40 (R2≧R1), and the body portion 40 is press-fitted into the insertion hole 22e against the elastic force of the press-fit portion 22. As a result, the press-fit portion 22 is configured to be able to slide along the circumferential direction on the outer circumferential surface of the body portion 40 when an external force of a certain level or more is applied in the circumferential direction about the axial direction A as the rotation axis. The press-fit portion 22 is also configured so that it is able to slide along the axial direction A on the outer circumferential surface of the body portion 40 when an external force of a certain level or more is applied along the axial direction A in the insertion direction X or the pull-out direction -X.

[0036] When the press-fit portion 22 moves toward the screw head 42 side (-X direction) along the expanded diameter portion 48 of the body 40, the other end 22c located on the screw head 42 side abuts against the end face 25a of the abutment portion 25 of the screw head 42 to be positioned. In addition, the press-fit portion 22 according to this embodiment is configured such that the inner diameter R1 of the insertion hole 22e is selected to be smaller than the outer diameter R3 of the protruding portion 24 of the body 40 (R3>R1), and when the press-fit portion 22 moves toward the screw body 20 side (X direction) along the expanded diameter portion 48 of the body 40, one end 22b located on the screw body 20 side can abut against the protruding portion 24 protruding radially outward.

[0037] Bumper portion 23 has bumper main body portion 23a formed in an annular shape from an elastic member such as rubber, and bumper main body portion 23a is fixed to screw head portion 42 so as to cover screw head portion 42. Bumper portion 23 according to this embodiment is provided such that screw head portion 42, which has irregularities on its outer circumferential surface, is embedded inside bumper main body portion 23a, and bumper main body portion 23a engages with the irregularities of screw head portion 42, thereby being firmly fixed.

[0038] Bumper main body portion 23a according to this embodiment is formed with a larger diameter than press-fit portion 22, and one end face 23b of bumper main body portion 23a is formed flush with end face 25a of abutment portion 25 of screw head 42. Furthermore, bumper portion 23 is arranged such that bumper main body portion 23a surrounds the periphery of abutment portion 25 of screw head 42, and when cue stick bumper 4 is attached to base end portion 3b of cue stick body 5, bumper main body portion 23a is arranged in close contact with the surface of base end portion 3b without any gaps, thereby maintaining high airtightness between cue stick body 5.

[0039] In addition, a bumper hole 23d is drilled in the other end face 23c of the bumper main body 23a, which is arranged opposite the one end face 23b, and as shown in Figures 3 and 4, an engagement hole 36 of the weight screw 9 is exposed to the outside from the bumper hole 23d.

[0040] (3) How to attach the cue stick bumper Next, we will explain how to attach the cue stick bumper 4 to the base end 3b of the cue stick body 5. In this case, as shown in Figure 5, the threaded body 20 of the weight screw 9 in the cue stick bumper 4 is inserted into the attachment hole 14 of the butt 3.

[0041] Next, a tool 100 such as a hexagonal bolt that can engage with the engagement hole 36 of the cue stick bumper 4 is prepared, and the tool 100 is inserted from the bumper hole 23d into the engagement hole 36 to engage the tool 100 with the engagement hole 36. Next, the tool 100 is rotated in the mounting direction for screwing the threaded body 20 into the mounting hole 14, thereby screwing the threaded body 20 of the cue stick bumper 4 into the mounting hole 14. At this time, as the threaded body 20 is inserted into the mounting hole 14, the press-fit portion 22 of the cue stick bumper 4 is gradually pressed into the interior of the mounting hole 14 from the opening 11.

[0042] When the press-fit portion 22 is press-fitted into the mounting hole 14, it is pressed against the inner circumferential surface of the mounting hole 14, and the other end 22c located on the side of the screw head 42 abuts against the end face 25a of the abutment portion 25 of the screw head 42 and is positioned. Furthermore, when an external force of a certain level or more is applied from the body portion 40 of the weight screw 9 and the inner circumferential surface of the mounting hole 14 when the screw body 20 is inserted into the mounting hole 14, the press-fit portion 22 can slide the body portion 40 of the weight screw 9 in the circumferential direction within the insertion hole 22e in response to the external forces applied.

[0043] As a result, the press-fit portion 22 can rotate the threaded body 20 in the mounting direction to be screwed into the mounting hole 14 while sliding the body portion 40 circumferentially inside the insertion hole 22e. As the threaded body 20 is inserted into the mounting hole 14, the press-fit portion 22 is pressed by the abutment portion 25 approaching the mounting hole 14, and is press-fitted into the mounting hole 14. At this time, the press-fit portion 22 is gradually press-fitted into the mounting hole 14 without rotating circumferentially inside the mounting hole 14, or is gradually press-fitted into the mounting hole 14 while rotating following the rotation of the threaded body 20.

[0044] In contrast to this embodiment, in the case of a cue stick bumper (hereinafter also referred to as a comparative cue stick bumper) in which the press-in portion 22 and the bumper portion 23 are integrally formed and the press-in portion 22 and the bumper portion 23 are fixed to the weight screw 9, when the weight screw 9 is rotated within the mounting hole 14, the press-in portion 22 will also attempt to rotate in the same manner as the weight screw 9. Therefore, to start rotating the stationary weight screw 9, in addition to the force to rotate the threaded body 20 of the weight screw 9, a force to slide the outer peripheral surface of the press-fit portion 22 along the inner peripheral surface of the mounting hole 14 is also required. Since the press-fit portion 22 is pressed into the mounting hole 14 with a large force in order to seal the mounting hole 14 with the press-fit portion 22, a large rotational force must be applied to the cue stick bumper. In this case, a large force is required to rotate both the weight screw 9 and the press-fit portion 22 at the same time, which causes a problem of a large burden during the installation work. Furthermore, in this type of comparative example cue stick bumper, if excessive force is applied when turning the weight screw 9, a large load will also be applied to the press-in portion 22, which may damage the press-in portion 22 sliding against the inner surface of the mounting hole 14.

[0045] In contrast, in the cue stick bumper 4 according to this embodiment, the body 40 of the weight screw 9 is configured to be slidable in the insertion hole 22e of the press-in portion 22, so that the threaded body 20 of the weight screw 9 can be rotated without necessarily applying a force to slide the press-in portion 22 along the inner circumferential surface of the mounting hole 14. For example, this embodiment can be configured such that the force with which the body 40 is pressed into the insertion hole 22e is weakened, while the press-in portion 22 is pressed into the mounting hole 14 with a strong force. In this case, the stationary weight screw 9 can be started to rotate with a force smaller than the force that rotates both the weight screw 9 and the press-in portion 22 simultaneously, and the burden during the mounting work can be reduced accordingly.

[0046] Furthermore, in the cue stick bumper 4, even if excessive force is applied to the weight screw 9 when the weight screw 9 is rotated, the body 40 slides and rotates within the insertion hole 22e of the press-fit portion 22, so that the force applied to the press-fit portion 22 can be dispersed, and the burden on the press-fit portion 22 can be reduced accordingly, and damage to the press-fit portion 22 can be prevented. In particular, as the screw body 20 is screwed in, the screw head 42 gradually approaches the mounting hole 14, so that a force that pushes the thick press-fit portion 22 into the mounting hole 14 along the axial direction A can be applied from the screw head 42 to the press-fit portion 22. Therefore, the press-fit portion 22 can be pressed into the mounting hole 14 with reduced burden on the press-fit portion 22 without applying unnatural distortion to the press-fit portion 22 due to the rotational force from the body 40.

[0047] In this manner, as shown in Figure 6, the cue stick bumper 4 has the screw body 20 and the press-fit portion 22 inserted into the mounting hole 14 until the bumper portion 23, which has a diameter larger than that of the mounting hole 14, abuts against the base end 3b of the cue stick body 5. This allows the cue stick bumper 4 to be attached to the base end 3b of the cue stick body 5.

[0048] Fig. 7 is a vertical cross-sectional view showing the vertical cross-sectional configuration when the cue stick bumper 4 is attached to the base end 3b of the cue stick body 5. As shown in Fig. 7, the cue stick bumper 4 is inserted into the attachment hole 14 in the insertion direction X, and the threaded body 20 of the weight screw 9 is screwed into the threaded region 12 in the attachment hole 14, and the cue stick bumper 4 is attached to the base end 3b of the cue stick body 5. At this time, the body 40 and enlarged diameter portion 48 of the weight screw 9 and the press-fit portion 22 of the cue stick bumper 4 are positioned in the non-threaded region 13 of the attachment hole 14.

[0049] The cue stick bumper 4 has the press-fit portion 22 which fits tightly against the inner circumferential surface of the mounting hole 14, and the abutment portion 25 of the weight screw 9 and the bumper portion 23 which are arranged to close the opening 11 of the mounting hole 14, thereby sealing the mounting hole 14 with the press-fit portion 22, the abutment portion 25 and the bumper portion 23. In this way, the cue stick bumper 4 can be fixed to the cue stick body 5 without moving freely relative to the cue stick body 5 by screwing the screw body 20 into the mounting hole 14 of the cue stick body 5 and by press-fitting the press-fit portion 22 into the mounting hole 14.

[0050] (4) How to remove the cue stick bumper Next, a method for removing the cue stick bumper 4 from the base end 3b of the cue stick body 5 will be described. In this case, in the cue stick bumper 4 (FIGS. 6 and 7) attached to the cue stick body 5, a tool 100 is inserted from the bumper hole 23d into the engagement hole 36, and the tool 100 is engaged with the engagement hole 36. Next, the tool 100 engaged with the engagement hole 36 of the cue stick bumper 4 is rotated in the opposite direction (removal direction) from the attachment, thereby moving the threaded body 20 within the attachment hole 14 in the pull-out direction -X.

[0051] In the cue stick bumper 4, as the threaded body 20 is removed from the inside of the mounting hole 14 to the outside, the press-fit portion 22 is also gradually pulled out from the opening 11 of the mounting hole 14. Here, Fig. 8 is a vertical cross-sectional view showing the state in which the cue stick bumper 4 is in the process of being removed from the base end portion 3b of the cue stick body 5. As shown in Fig. 8, as the threaded body 20 is removed from the inside of the mounting hole 14, the press-fit portion 22 of the cue stick bumper 4 is gradually pulled out from the inside of the mounting hole 14.

[0052] When the tool 100 engaged with the cue stick bumper 4 is rotated in the direction of removing it from the mounting hole 14, since the press-in portion 22 is pressed into the inside of the mounting hole 14, the body portion 40 also slides circumferentially inside the insertion hole 22a of the press-in portion 22, while the screw body 20 screwed into the mounting hole 14 is rotated in the direction of removing it from the mounting hole 14.

[0053] Furthermore, when the threaded body 20 is moved in the direction -X to be pulled out from the mounting hole 14, the press-fit portion 22 is pulled against the inner peripheral surface of the mounting hole 14 because it is press-fitted into the interior of the mounting hole 14. As a result, the threaded body 20 is pulled out from the mounting hole 14 while the body portion 40 slides in the axial direction A inside the insertion hole 22e of the press-fit portion 22. As a result, the bumper portion 23 also gradually moves away from the base end portion 3b of the cue stick body 5, and the end portion 22c of the press-fit portion 22, which was in contact with the contact portion 25 of the weight screw 9, gradually moves away from the bumper portion 23.

[0054] Furthermore, as the screw body 20 is pulled out from inside the mounting hole 14, the trunk portion 40 slides through the insertion hole 22e of the press-in portion 22 while being pulled out from the mounting hole d14, and the end portion 22c of the press-in portion 22 moves away from the abutment portion 25 by a distance L along the axial direction A, the end portion 22b of the press-in portion 22 on the screw body 20 side abuts against the protrusion portion 24 of the weight screw 9, and the press-in portion 22 is positioned at the position of the protrusion portion 24.

[0055] When the threaded body 20 is rotated in a direction to remove it from the mounting hole 14, the overhanging portion 24 moves in the pulling direction -X, and the press-fit portion 22 is pushed by the overhanging portion 24 and pulled out of the mounting hole 14. At this time, the press-fit portion 22 is pushed by the overhanging portion 24 and pulled out of the mounting hole 14 without rotating in the circumferential direction inside the mounting hole 14, or is pushed by the overhanging portion 24 and pulled out of the mounting hole 14 while rotating following the rotation of the threaded body 20.

[0056] In contrast to this embodiment, in a comparative example of a cue stick bumper in which the press-in portion 22 and the bumper portion 23 are formed integrally and the press-in portion 22 and the bumper portion 23 are fixed to the weight screw 9, even when removing the cue stick from the cue stick body 5, when the weight screw 9 is rotated within the mounting hole 14, the press-in portion 22 will also attempt to rotate in the same manner as the weight screw 9. Therefore, even when removing the weight screw 9, in order to start rotating the stationary weight screw 9, in addition to the force to rotate the threaded body 20 of the weight screw 9, a force to slide the outer surface of the press-in portion 22 along the inner surface of the mounting hole 14 is also required, which creates the problem of a large burden during the removal work. Furthermore, in the case of this comparative example cue stick bumper, if excessive force is applied when turning the weight screw 9 during removal, a correspondingly large force will also be applied to the press-fit portion 22, which may damage the press-fit portion 22 sliding against the inner surface of the mounting hole 14.

[0057] In contrast, in the cue stick bumper 4 according to this embodiment, the body 40 of the weight screw 9 is configured to be slidable in the insertion hole 22e of the press-in portion 22, so that even during removal, the threaded body 20 of the weight screw 9 can be rotated without applying a force that slides the press-in portion 22 along the inner circumferential surface of the attachment hole 14. Therefore, even during removal, the stationary weight screw 9 can be started to rotate with a force smaller than the force required to simultaneously rotate both the weight screw 9 and the press-in portion 22, thereby reducing the burden during the removal work.

[0058] Furthermore, when removing the cue stick bumper 4, even if excessive force is applied to the weight screw 9 when rotating the weight screw 9, the body 40 slides and rotates within the insertion hole 22e of the press-in portion 22, so that the force applied to the press-in portion 22 can be distributed, thereby reducing the burden on the press-in portion 22 and preventing damage to the press-in portion 22.

[0059] In this way, the threaded body 20 and the press-fit portion 22 of the cue stick bumper 4 can be pulled out from within the mounting hole 14, and the cue stick bumper 4 can be removed from the base end 3b of the cue stick body 5.

[0060] (5) How to adjust the weight and center of gravity of the cue stick Next, a method for adjusting the weight and center of gravity of the cue stick 1 using the cue stick bumper 4 will be described. Fig. 9 shows five cue stick bumpers 4a, 4b, 4c, 4d, and 4e in which the weights are changed by changing the lengths of the threaded bodies 20a, 20b, 20c, 20d, and 20e in the axial direction A. In the example shown in Fig. 9, the cue stick bumpers 4a, 4b, 4c, 4d, and 4e are all different only in the lengths of the threaded bodies 20a, 20b, 20c, 20d, and 20e, and the material and outer diameter of the threaded bodies 20a, 20b, 20c, 20d, and 20e are the same, and the material and shape of the press-fit portion 22 and the bumper portion 23 are also the same, and the longer the length of the threaded bodies 20a, 20b, 20c, 20d, and 20e, the heavier they are.

[0061] For example, among the cue stick bumpers 4a, 4b, 4c, 4d, and 4e, the cue stick bumper 4a has the shortest length of threaded body 20a and is the lightest among these five cue stick bumpers 4a, 4b, 4c, 4d, and 4e. On the other hand, among the cue stick bumpers 4a, 4b, 4c, 4d, and 4e, the cue stick bumper 4e has the longest length of threaded body 20e and is the heaviest among these five cue stick bumpers 4a, 4b, 4c, 4d, and 4e.

[0062] The weight and center of gravity of the cue stick 1 can be adjusted by selecting, for example, cue stick bumper 4a from among cue stick bumpers 4a, 4b, 4c, 4d, and 4e and attaching it to the base end 3b of the cue stick body 5 according to the player's preference and purpose.

[0063] In this embodiment, the weight of the cue stick bumper 4a, 4b, 4c, 4d, 4e is changed by simply changing the length of the threaded bodies 20a, 20b, 20c, 20d, 20e in the axial direction A, but the present invention is not limited to this. For example, the weight of the cue stick bumper 4a, 4b, 4c, 4d, 4e may be changed by changing the length and material of the threaded bodies 20a, 20b, 20c, 20d, 20e, or the weight of the cue stick bumper 4 may be changed by changing the material of the weight screw 9 while keeping the length of the threaded body 20 in the axial direction A the same.

[0064] (6) Actions and Effects In the above-described configuration, the cue stick bumper 4 comprises a weight screw 9 that can be screwed into the mounting hole 14 of the cue stick body 5, a press-in portion 22 in which the body portion 40 of the weight screw 9 is slidably arranged in the insertion hole 22e, and a bumper portion 23 that is separate from the press-in portion 22 and is fixed to the screw head portion 42 of the weight screw 9.

[0065] As a result, by providing the press-in portion 22 and the bumper portion 23 on the weight screw 9, the cue stick bumper 4 can be attached to or removed from the mounting hole 14 together with the weight screw 9, making it easier to replace the cue stick bumper 4 and, accordingly, making it easier to adjust the weight and center of gravity of the cue stick body 5 than before.

[0066] Furthermore, when an external force of a certain level or more is applied from the body 40 of the weight screw 9 to the press-in portion 22, the body 40 of the cue stick bumper 4 can slide within the insertion hole 22e of the press-in portion 22, thereby preventing excessive external force from being applied from the weight screw 9 to the press-in portion 22 and reducing the burden on the press-in portion 22.

[0067] When attaching the cue stick bumper 4 to the mounting hole 14, the end 22c of the press-in portion 22 abuts against the bumper portion 23 and the screw head 42 to be positioned. Then, when the screw body 20 is rotated in the attachment direction to screw it into the mounting hole 14, the body portion 40 slides circumferentially inside the insertion hole 22e while the screw body 20 is inserted into the mounting hole 14. Furthermore, as the screw head 42 approaches the mounting hole 14, the press-in portion 22 is pushed by the abutment portion 25 and is press-fitted into the mounting hole 14.

[0068] As a result, when attaching the cue stick bumper 4 to the mounting hole 14, the press-in portion 22 and the bumper portion 23 can be attached to the mounting hole 14 together with the weight screw 9, facilitating the work of replacing the cue stick bumper 4. Furthermore, when attaching the cue stick bumper 4 to the mounting hole 14, the body portion 40 can slide within the insertion hole 22e of the press-in portion 22, which can prevent excessive external force from being applied to the press-in portion 22 from the weight screw 9 and can reduce the burden on the press-in portion 22.

[0069] When the cue stick bumper 4 attached to the mounting hole 14 is to be removed from the mounting hole 14, the threaded body 20 screwed into the mounting hole 14 is rotated in the direction of removal from the mounting hole 14, and while the body portion 40 slides inside the insertion hole 22e in the axial direction A and circumferential direction of the body portion 40, the threaded body 20 is pulled out of the mounting hole 14. As the threaded body 20 is pulled out of the mounting hole 14, the bumper portion 23 moves away from the mounting hole 14, and the press-fit portion 22 moves away from the bumper portion 23 and is pulled out of the mounting hole 14.

[0070] As a result, when removing the cue stick bumper 4 from the mounting hole 14, the press-in portion 22 and the bumper portion 23 can be removed together with the weight screw 9 from the mounting hole 14, facilitating the work of replacing the cue stick bumper 4. Furthermore, when removing the cue stick bumper 4 from the mounting hole 14, the body portion 40 can slide within the insertion hole 22e of the press-in portion 22, which can prevent excessive external force from being applied to the press-in portion 22 from the weight screw 9 and can reduce the burden on the press-in portion 22.

[0071] (7) Other embodiments In the above-described embodiment, the case has been described in which the body portion 40 is arranged inside the insertion hole 22e of the press-fit portion 22 so as to be slidable in the axial direction A and circumferential direction of the body portion 40. However, the present invention is not limited to this. For example, the body portion 40 may be arranged inside the insertion hole 22e of the press-fit portion 22 so as to be slidable in either the axial direction A or the circumferential direction of the body portion 40.

[0072] In the above embodiment, when the cue stick bumper 4 is attached to the attachment hole 14, the end 22c of the press-fit portion 22 abuts against the abutment portion 25 provided on the screw head 42 to determine its position, but the present invention is not limited to this. For example, the screw head 42 may be sunk into the bumper portion 23, and an abutment portion against which the end 22c of the press-fit portion 22 abuts may be provided on the bumper portion 23. In this case, when the cue stick bumper 4 is attached to the attachment hole 14, the end 22c of the press-fit portion 22 abuts against the abutment portion of the bumper portion 23 to determine its position, and the press-fit portion 22 is pressed into the attachment hole 14 by the abutment portion. [Explanation of symbols]

[0073] 1 Cue Stick 3b Proximal end 4, 4a, 4b, 4c, 4d, 4e Cue stick bumpers 5. Cue stick body 9 Weight Screw 14 Mounting hole 20, 20a, 20b, 20c, 20d, 20e Threaded body 22 Press-fit section 22e Insertion hole 23 Bumper section 24 Overhang 40 Torso 42 Screw head

Claims

1. A cue stick bumper is detachably attached to an attachment hole formed in a base end of a rod-shaped cue stick body that is used to strike a ball with its tip, a weight screw having a screw body that can be screwed into the mounting hole, a body portion connected to the screw body, and a screw head portion connected to the body portion; a press-fit portion which is a cylindrical body having the body portion slidably provided in an insertion hole and is press-fitted into the mounting hole; A bumper portion which is separate from the press-fit portion and fixed to the head portion of the screw; A bumper for a cue stick.

2. The press-fit portion is provided so that the body portion can slide in the axial and circumferential directions of the body portion inside the insertion hole.

2. A bumper for a cue stick according to claim 1.

3. When the cue stick bumper attached to the mounting hole is removed from the mounting hole, When the screw body screwed into the mounting hole is rotated in a removal direction, the body slides in the axial and circumferential directions of the body inside the insertion hole while the screw body is pulled out of the mounting hole, and the bumper portion moves away from the mounting hole, and the press-fit portion separates from the bumper portion and is pulled out of the mounting hole.

3. A bumper for a cue stick according to claim 1 or 2.

4. The weight screw has a protruding portion is provided against which an end of the press-fit portion comes into contact when the press-fit portion is separated from the bumper portion; 4. A bumper for a cue stick according to claim 3.

5. The body portion is A columnar connecting portion connected to the threaded body, and a columnar enlarged diameter portion having a diameter larger than that of the connecting portion and in which the press-fit portion is slidably provided, The protruding portion is The connecting portion has a ring shape extending radially outward along a circumferential direction at a predetermined position of the connecting portion.

5. A bumper for a cue stick according to claim 4.

6. A cue stick having a rod-shaped cue stick body with a tip portion for striking a ball, and a cue stick bumper that is detachably attached to an attachment hole formed in a base end portion of the cue stick body, A cue stick bumper, which is a cue stick bumper according to any one of claims 1 to 5.

7. A method for attaching a cue stick bumper to a proximal end of a cue stick body, comprising: The cue stick bumper is a weight screw having a screw body that can be screwed into the mounting hole at the base end, a body portion connected to the screw body, and a screw head portion connected to the body portion; a press-fit portion which is a cylindrical body having the body portion slidably provided in an insertion hole and is press-fitted into the mounting hole; A bumper portion which is separate from the press-fit portion and fixed to the head portion of the screw; having When the cue stick bumper is attached to the mounting hole, an end of the press-in portion abuts against an abutment portion provided on at least one of the bumper portion and the screw head portion to position the bumper portion and the screw body is rotated in an attachment direction to screw the screw body into the mounting hole, and the body slides circumferentially inside the insertion hole while the screw body is inserted into the mounting hole, and the press-in portion is pressed by the abutment portion and pressed into the mounting hole. How to install a bumper for a cue stick.

8. A method for removing a cue stick bumper attached to a base end of a cue stick body, comprising the steps of: The cue stick bumper is a weight screw having a screw body that can be screwed into an attachment hole at the base end of the cue stick body, a body portion connected to the screw body, and a screw head portion connected to the body portion; a press-fit portion which is a cylindrical body having the body portion slidably provided in an insertion hole and is press-fitted into the mounting hole; A bumper portion which is separate from the press-fit portion and fixed to the head portion of the screw; having When the cue stick bumper attached to the mounting hole is removed from the mounting hole, the screw body screwed into the mounting hole is rotated in a direction to be removed from the mounting hole, so that the body slides in the axial and circumferential directions of the body inside the insertion hole while the screw body is pulled out of the mounting hole, and the bumper portion moves away from the mounting hole, and the press-fit portion separates from the bumper portion and is pulled out of the mounting hole. How to remove the bumper for a cue stick.

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