JP6033481B1 - Earth top - Google Patents

Abstract

An earth top having one or more of the advantages of being easy to manufacture, easy to operate, and capable of sustaining rotation. An earth top 1 includes a disk portion 5, a rotating disk 2 composed of an upper core shaft portion 7 and a lower core shaft portion 8 extending on an extension line of a central axis P of the disk portion 5, and a horizontal protective frame 3. And a vertical protective frame 4 fixed at a crossing position with the horizontal protective outer frame 3. An upper rotation support shaft 20 and a lower rotation support shaft 21 are provided at two top positions 180 degrees apart from each other on the vertical protective frame 4. Conical pointed heads 44 and 45 are formed at the front end portions of the upper core shaft portion 20 and the lower core shaft portion facing each other, and shaft holes are formed in the opposite end surfaces of the upper rotation support shaft 20 and the lower rotation support shaft 21. 33 and 35 are provided. Bearing members 34 and 42 made of resin having a small coefficient of friction with the pointed heads 44 and 45 are inserted into the shaft holes 33 and 35. [Selection] Figure 2

Description

  The present invention relates to a globe and a method for producing the globe.

  For a long time, the Earth Top has been known as a top toy that applies the principle of the gyro effect (for example, Patent Document 1). The Earth Top can rotate with a rotating disk called a spinning top and a rotating support shaft that supports the core axis of the rotating disk, so if the rotating disk rotates at a high speed, it rotates with the top body tilted. Or a tightrope on a wire. Such a globe has a pair of core shafts provided on the front side and the back side perpendicular to the disk surface of the rotary disk, and a pair of rotation support shafts that rotatably support the tips of the core shafts. . On the outside of the rotating disk, a ring-shaped protective frame (called a horizontal protective frame) parallel to the rotating disk and a ring-shaped protective frame (called a vertical protective frame) perpendicular to the horizontal protective frame are provided. The rotation support shaft has a structure that can move from both ends of the core shaft toward the tip of the core shaft and away from the tip of the core shaft, and the rotational load on the rotating disk is minimized. Thus, the distance of the rotation support shaft can be adjusted.

JP-A-7-220911

  Up to the earth described in Patent Document 1, rotational force is given to the rotating disk by a motor. However, the Earth Top can rotate the rotating disk with a string or the like. In such a rotating disk of the top of the earth, the pointed heads at both ends of the core shaft are supported by the rotation support shaft. In order to maintain high-speed rotation of the rotating disk for a long time, the friction loss between the core shaft and the rotation support shaft must be reduced. However, both the conventional core shaft and the rotation support shaft are made of an iron-based alloy or stainless steel, and have a problem that rotation is easily damped due to friction loss because of a large friction coefficient. In addition, there is a problem that the position of the contact portion between the tip of the core shaft and the rotation support shaft moves in the radial direction during the rotation, the friction loss increases, and the rotation cannot be sustained for a long time.

  The horizontal protective frame and the vertical protective frame are thin-walled ring members having an outer diameter of several tens of mm (some larger and some smaller), for example. Such a ring member is generally formed by cutting a bar, but it takes a lot of processing time, and there is a problem that the amount of cutting is large and the material is wasted. . There is also a method of forming a ring shape by rounding a ribbon-like thin plate by plastic working and fitting and joining both ends, but a special manufacturing tool (such as a mold) is required, or it is formed into a perfect circle However, there is a problem that skill is required.

  In addition, the conventional top that rotates the rotating disk with a string has a single hole for winding the string on one side of the disk part of the core shaft. There is a problem that it is difficult to do.

  The present invention has been made in view of such a problem, and an object of the present invention is to realize a global top that solves one or more of the problems described above.

  In order to solve one or more of the above problems, the earth top of the present invention includes a disk part, a first core shaft part extending in the opposite direction from the disk part on the extension line of the central axis of the disk part, and a second core part. A rotating disk having a core shaft portion, a ring-shaped first protective frame disposed so as to surround the outer periphery of the disk portion with a certain distance, and orthogonal to the first protective frame. And a ring-shaped second protective frame fixed to the first protective frame at a position intersecting with the first protective frame, and a rotary disk at each top position 180 degrees away from the second protective frame. A first rotation support shaft and a second rotation support shaft that are movable toward and away from each other; A conical pointed head is formed at each tip portion of the first core shaft portion and the second core shaft portion facing each rotation support shaft, and the first rotation support shaft and the second rotation support shaft are formed. A bottomed shaft hole is provided on each end surface facing each core shaft portion of the resin, and the shaft hole is made of a resin having a small friction coefficient between the first core shaft portion and the second core shaft portion. A bearing member is inserted. The rotating disk is provided with an axial clearance between the pointed head and the bearing member.

  In addition to the above invention, the first protective frame and the second protective frame are formed by cutting a metal pipe at a right angle with respect to the extending direction of the pipe and are seamless. Both the first protective frame and the second protective frame are preferably provided with through-holes at two positions 180 degrees apart, and the positions of both through-holes are aligned and joined so as to be orthogonal to each other.

  Further, in addition to the above-described invention, the surface on which the pointed portion of the first core shaft portion of the bearing member on the first rotation support shaft side hits and the second core shaft of the bearing member on the second rotation support shaft side It is preferable that an indentation that follows the shape of the apex of each of the cusps is formed on the surface of the cusp.

  In addition to the above invention, the bearing member includes a shaft hole that forms a radial position of the rotating disk, and a receiving surface that regulates the position of the rotating disk in the central axis direction at the bottom of the shaft hole. It is preferable.

  In addition to the above invention, the rotating disk includes a disk portion and a core shaft that passes through the central axis of the disk portion, and one end of the core shaft serves as a first core shaft portion, and the other end of the core shaft. Is preferably the second core shaft portion.

  The method of manufacturing the top of the earth according to the present invention includes the steps of cutting two kinds of metal pipes having different diameters at right angles to the extending direction of each pipe to form two kinds of rings having different diameters without seams. , Processing the inner periphery of each ring into a substantially perfect circle, and using each ring as a first protective frame and a second protective frame, the first protective frame and the second protective frame are separated by 180 degrees, respectively. There are a step of providing through holes at two locations and a step of aligning the positions of the through holes of both protective frames and joining them so as to be orthogonal to each other.

It is the perspective view which looked at the earth top which concerns on embodiment of this invention from the front side (the side of a rotating disk). It is the front view which looked at the earth top which concerns on embodiment of this invention from the side of the rotary disk. It is sectional drawing which expands and shows the fitting state of the upper rotation support shaft and upper shaft center part of FIG. 2A. It is sectional drawing which expands and shows the fitting state of the lower rotation support shaft of FIG. 2A, and a lower core shaft part. It is a figure which shows the horizontal protection frame and vertical protection frame which concern on embodiment of this invention, (A) is a longitudinal cross-sectional view cut | disconnected by the cutting line which passes along the central axis of FIG. These are the side views seen from the right side of FIG. It is a figure which shows the support structure of the upper core shaft part by the upper rotation support shaft which concerns on the modification of embodiment of this invention. It is a figure which shows the modification of the disc part 5 and the core shaft 6 of this invention, (A) is a 1st modification, (B) is a figure which shows a 2nd modification.

(Configuration of Earth Top 1)
Hereinafter, the earth top 1 according to the embodiment of the present invention will be described with reference to the drawings. 1 can be used even if the posture of FIG. 1 is reversed, but for the convenience of explanation, the upper side of FIG. 1 is upward, the lower side is lower, the right side is right, and the left side is illustrated. It will be described as the left side.

  FIG. 1 is a perspective view of the earth top 1 according to the embodiment of the present invention as viewed from the front side of the drawing. As shown in FIG. 1, the earth top 1 has a rotating disk 2 that can rotate around a central axis P, a ring shape that has a fixed distance from the outer periphery of the rotating disk 2 and is parallel to the disk part 5 of the rotating disk 2. The first protective frame 3 and a ring-shaped second protective frame 4 that is orthogonal to the first protective frame 3 and is arranged inside the first protective frame 3 are provided. In order to distinguish between the first protective frame 3 and the second protective frame 4, the first protective frame 3 is described as a horizontal protective frame 3, and the second protective frame 4 is described as a vertical protective frame 4. The horizontal protective frame 3 and the vertical protective frame 4 are fixed and integrated at positions where the right side and the left side cross each other. The horizontal protective frame 3 and the vertical protective frame 4 are made of metal pipes having different diameters as raw materials (large diameter for the horizontal protective frame 3 and small diameter for the vertical protective frame 4) perpendicular to the extending direction of the pipe. It is formed by cutting, i.e., cutting. In addition, after the ring is cut, a perfect circle is processed so that the inner circumference thereof is almost a perfect circle.

The rotating disk 2 includes a disk part 5 and a core shaft 6 that extends in the vertical direction from the disk surface of the disk part 5. Of the core shaft 6, the upper portion from the disk portion 5 is an upper core shaft portion 7 that is a first core shaft portion, and the lower side is a lower core shaft portion 8 that is a second core shaft portion. The central axes of the upper core shaft portion 7 and the lower core shaft portion 8 coincide with the rotation central axis P of the disk portion 5. In the example shown in FIG. 1, the rotating disk 2 is formed by integrally forming a disk portion 5 and a core shaft 6 by cutting a metal bar such as an iron alloy or stainless steel. Then, after being formed in the shape of the rotating disk 2, it is cured to about HRC (Rockwell hardness) 55 by a curing process. By forming the rotary disk 2 integrally with the disk part 5 and the core shaft 6, the inertia of the upper side and the lower side including the disk part 5 can be made the same, and the attitude of the earth top 1 is changed. Sometimes, the rotating disk 2 prevents inertia imbalance. The upper core shaft portion 7 and the lower core shaft portion 8 each distal end side, a rotation shaft portions 9 and 10 (see FIG. 2 A). In addition, you may make it manufacture the rotary disk 2 by mold shaping | molding, such as lead, zinc, and those alloys.

  The upper core shaft part 7 extends perpendicularly to the disk surface of the disk part 5 from the base part 11 connected to the disk part 5. The upper core shaft portion 7 has a hole 12 that passes through the shaft. This hole 12 is a hole for passing a string (not shown) that gives a rotational force to the rotating disk 2 and is wound around the hole 12 and is hereinafter referred to as a string winding hole 12. The lower core shaft portion 8 has the same shape as the upper core shaft portion 7, but has the same shape, and has a string winding hole 13 at a symmetrical position with respect to the string winding hole 12. The rotary disk 2 is supported by an upper rotation support shaft 20 that is a first rotation support shaft and a lower rotation support shaft 21 that is a second rotation support shaft via a core shaft 6.

As shown in FIG. 1, the upper rotation support shaft 20 has a shaft portion 23 that extends from the head portion 22 toward the upper core shaft portion 7. A screw portion 24 is formed on the shaft portion 23. The screw portion 24 is screwed into a screw hole provided in the vertical protective frame 4 and protrudes from the screw hole. A bottomed shaft hole 33 (see FIGS. 2A and 2B ) is formed below the shaft portion 23, and the rotation shaft portion 9 of the upper core shaft portion 7 is inserted into the shaft hole 33. Yes. The upper rotation support shaft 20 advances downward (in the direction approaching the rotating disk 2) by rotating right and advances upward (in the direction away from the rotating disk 2) by rotating left. Further, the lower rotation support shaft 21 has a shaft portion 26 that extends from the head portion 25 toward the lower core shaft portion 8. A screw portion 27 is formed on the shaft portion 26. The screw portion 27 is screwed into a screw hole provided in the vertical protective frame 4 and protrudes from the screw hole. A bottomed shaft hole 35 (see FIGS. 2A and 2C ) is formed on the upper side of the shaft portion 26, and the rotary shaft portion 10 of the lower core shaft portion 8 is inserted into the shaft hole 35. The lower rotation support shaft 21 is rotated rightward as viewed from the lower side and proceeds upward (in a direction approaching the rotating disk 2), and proceeds downward (in a direction away from the rotating disk 2) when rotated left. The center axis of the upper rotating support shaft 20, the core shaft 6 of the rotating disk 2, and the lower rotating support shaft 21 are arranged on the center axis P of the rotating disk 2 in the assembled state as shown in FIG. The relationship between the core shaft 6 of the rotating disk 2, the upper rotating support shaft 20, and the lower rotating support shaft 21 will be described in detail with reference to FIG.

Figure 2 A is a front viewing the Earth frame 1 from the side of the rotating disc 2, and FIG. 2B is an enlarged sectional view showing the fitting state of the lower rotary support shaft 21 and the lower core shaft portion 8, Figure 2C These are sectional drawing which expands and shows the fitting state of the upper rotation support shaft 20 and the lower core shaft part 7. FIG. Incidentally, in FIG. 2 A, the horizontal protective frame 3 is represented by a two-dot chain line because they are located at the same height as the disc portion 5. As shown in FIG. 2 A, vertical protective frame 4 with horizontal protective frame 3 is fixed by bonding means such as brazing at location A, B cross each other. The horizontal protective frame 3 is provided with a pair of through holes 30 on a straight line orthogonal to the central axis P. The vertical protective frame 4 is provided with a pair of through holes 31 on a straight line passing through the center P1 of the vertical protective frame 4 and orthogonal to the central axis P. The horizontal protective frame 3 and the vertical protective frame 4 are joined in such a manner that the positions of the through holes 30 of the horizontal protective frame 3 and the through holes 31 of the vertical protective frame 4 are aligned and orthogonal to each other. Details of this will be described later with reference to FIG.

As shown in FIG. 2 A, the central portion of the upper core shaft portion 7, cord wound hole 12 is drilled. The string winding hole 12 has a side surface formed on the rotating shaft portion 9 on the side of the base portion 11 from the arc-shaped taper portion 37 to a substantially central portion of the columnar portion between the arc-shaped taper portion 38. Is provided. In addition, a cylindrical string winding hole 13 is opened at the same position as the upper core shaft 9 on the lower core shaft portion 8 side. That is, the string winding hole 13 has a columnar shape between a tapered portion 39 having a circular arc-shaped side surface formed on the distal end side of the rotary shaft portion 10 and a tapered portion 40 having a circular arc-shaped side surface formed on the base 11 side. It is provided almost at the center of the part. The string winding holes 12 and 13 are provided symmetrically at a target position with the center of gravity of the disk portion 5 as the center. The string wrapping holes 12 and 13 may not be provided at the target position, or may not be symmetric such that one is enlarged and the other is reduced.

The string winding holes 12 and 13 have a diameter (for example, 2.2 mm) through which the wound string can easily pass, and the entrance portion is chamfered. By having the chamfer in this way, it is easy to pass the string through the string winding holes 12, 13, to facilitate winding, and after applying a rotational force to the rotating disk 2, the string is wound around the holes 12, 13. It is easy to remove from. In FIG. 2 A, cord wound hole 12, 13 has been drilled in the same direction with respect to the upper rotary shaft portion 20 and the lower rotation shaft 21 may not be the same direction, e.g., horizontal You may dawn at a position shifted by 90 degrees in the direction. Also, the diameter of the holes may be different, or a conical hole may be used.

The upper rotation support shaft 20 is formed with a bottomed shaft hole 33 from an end surface 32 on the upper core shaft portion 7 side. A cylindrical bearing member 34 is inserted into the bottom of the shaft hole 33. A clearance of 0.02 mm to 0.05 mm is provided in the radial direction of the shaft hole 33 and the rotary shaft portion 9. An upper end portion of the upper rotation support shaft 20 has a head portion 22 having a diameter larger than that of the shaft portion 23, and a single character groove (minus groove) 36 is provided. The groove 36 is, in addition to the driver slot to rotate the upper rotation shaft 20, when the reverse orientation of the earth frame 1 with respect to FIG. 2 A, is fitted such as to groove the yarn or wire, thread or wire It is possible to rotate the Earth Top 1 on the top.

  Similarly to the upper rotation support shaft 20, the lower rotation support shaft 21 has a bottomed shaft hole 35 from the end surface 41 on the lower core shaft portion 8 side. A cylindrical bearing member 42 is inserted into the bottom of the shaft hole 35. A clearance of 0.02 mm to 0.05 mm is provided in the radial direction of the shaft hole 35 and the rotary shaft portion 10. A lower end portion of the lower rotation support shaft 21 has a head portion 25 having a diameter larger than that of the shaft portion 26, and a conical recess 43 is formed on the top surface of the head portion 25. The recess 43 allows the earth top 1 (recess 43) to be placed on a pointed member (for example, a pen tip) and rotated.

  The bearing members 34 and 42 can have the same shape, and the material is preferably a fluororesin having a low friction coefficient. Examples of the fluororesin include polytetrafluoroethylene (PTFE). The static friction coefficient (including the copper friction coefficient) of the combination of PEFE and iron-based metal is reduced to about 1/10 that of the combination of iron-based metal and iron-based metal. PEFE has a characteristic that mechanical strength is high among various resins. In addition to PTFE, the material of the bearing members 34 and 42 may be polyacetal resin (POM) having a low friction coefficient and high mechanical strength, and examples of the POM include a copolymer and a homopolymer.

The bearing members 34 and 42 have a simple cylindrical shape when used alone or immediately after assembly. A top 1 shown in FIG. 2A represents a posture when the central axis P is oriented in the vertical direction. At this time, the pointed head portion 44 of the lower core shaft portion 8 contacts the bearing member 42, and the pointed head portion 45 of the upper core shaft portion 7 is separated from the bearing member 34. When the earth frame 1 is turned upside down from the orientation of FIG. 2 A is a peak portion 44 of the lower core shaft portion 8, away from the bearing member 42, the peak portion 45 of the upper core shaft portion 7, the bearing member 34 Contact. Thus, the rotary disk 2 has a clearance along the central axis P between the bearing member 34 and the bearing member 42. This clearance can be appropriately adjusted mainly by rotating the upper support rolling shaft 20. The clearance may be adjusted by rotating the lower rotation support shaft 21 or rotating both the upper rotation support shaft 20 and the lower rotation tooth shaft 21. In the example shown in FIG. 2 A, but the apex angle of the apex head 44, 45 is set to 90 degrees, may be in the range of 60 to 120 degrees. The bearing members 34 and 42 are softer than the core shaft 6. Therefore, it is possible to reduce the friction loss of the rotating disk 2 by utilizing this difference in hardness. This Figure 2 B, with reference to FIG. 2C will be described.

As described above, the bearing members 34 and 42 are softer than the core shaft 6. Thus, continued rotation of the rotary disk 2, the receiving surface 34A of each cusp portion of the bearing member 34, 42, 42A (FIG. 2 C, see FIG. 2B) attached has indentations cusp 45 and 44 in. Therefore, it is possible to actively use this indentation to reduce the lateral vibration of the rotating disk 2 after long-time rotation and the friction loss. As shown in FIG. 2 B, when the rotary disk 2 in a posture of Fig. 2 A, the peak portion 44 bites into the bearing member 42 on the lower side. Since this time, between the upper side of the bearing member 34 and the pointed head 45 there is a clearance, the bearing member 34 remains in the initial state (see FIG. 2 A). Here, when the earth top 1 is turned upside down, that is, when the rotating disk 2 is rotated with the upper rotation support shaft 20 facing downward, the pointed head 45 bites into the bearing member 34. In this way, an indentation 46 of the apex 44 is formed on the surface 42A of the bearing member 42, and an indentation 47 of the apex 45 is formed on the receiving surface 34A of the bearing member 34 (see FIG. 2C ). In this way, the clearance in the direction of the central axis P of the rotating disk 2 is increased from the initial value, so that the clearance is appropriately adjusted by the upper rotating support shaft 20 or the lower rotating support shaft 21.

  When the rotating disk 2 is rotated, an indentation 46 is formed on the receiving surface 42 </ b> A of the bearing member 42 by the weight of the rotating disk 2, for example, the pointed head 44 of the lower core shaft portion 8. Get in. Then, since the lower side of the rotating disk 2 is supported by the pointed head 44 and the indentation 46, the friction loss is reduced and the lateral vibration (direction intersecting the central axis P) can be suppressed. It becomes. When the earth top 1 is turned upside down, the tip 45 of the upper shaft portion 7 enters the indentation 47 of the bearing member 34 in the same manner as described above. If such indentations 46 and 47 are formed in advance in the rotation adjustment stage, it is possible to reduce the rotational load when the rotating disk 2 rotates.

The indentations 46 and 47 are formed by adjusting the clearance in the central axis P direction of the rotating disk 2 to 0 to minus and forcibly rotating the rotating disk 2 so that the indentations 46 and 47 have a predetermined size. It can be formed by repeating until. Thereafter, the upper rotation support shaft 20 or the lower rotation support shaft 21 is adjusted so as to obtain a predetermined clearance. At this time, it is preferable to adjust so that the disk portion 5 of the rotating disk 2 is at the same height as the horizontal protective frame 3. The state rotated 90 degrees from the earth frame 1 from the orientation of FIG. 2 A, for example, if a state where the center axis P is oriented horizontal, each of the rotating shaft 9, 10 and the shaft holes 33 and 35 Line contact is made in the axial direction. Further, as the method of forming the indentations 46, 47 on the side in contact with the rotary shaft portion 10 and 9 respectively of the bearing member 42, 34 receiving surfaces 42A, to 34A, the same shape as the cusp 44 and 45 prior to incorporation It can also be formed by a method of pressing using a jig. In addition, if the suitable indentations 46 and 47 are formed in advance, since the friction is small, the indentations 46 and 47 rarely spread continuously.

2C and 2B , the shaft hole 33 of the upper rotation support shaft 20 and the shaft hole 35 of the lower rotation support shaft 21 are both opened with a drilling tool such as a drill or a drill. A substantially conical tip recess 33A and a tip recess 35A in which the tip shape of the drilling tool is copied are formed at the tip of the hole, and this conical shape is left as it is. The bearing members 34 and 42 are formed by cutting from a rod material such as a fluororesin. At that time, when the bearing members 34 and 42 are separated from the bar material, convex portions 34B and 42B called “cut-off” are left at the center of the shaft. When the bearing members 34 and 42 are respectively inserted into the shaft holes 33 and 35, the convex portion 34B is accommodated in the tip concave portion 33A, and the convex portion 42B is accommodated in the tip concave portion 35A. In this way, variation in the axial position of the bearing members 34, 42 due to the presence of the convex portions 34B, 42B is prevented, and when the convex portions 34B, 42B remain largely, the positioning of the bearing members 34, 42 is determined. It can be performed.

  As described above, the horizontal protective frame 3 and the vertical protective frame 4 are fixed so as to be orthogonal to each other. It is not easy to fix the two ring-shaped members so as to be orthogonal to each other. The fixing method will be described with reference to FIG.

  3 is a view showing the horizontal protective frame 3 and the vertical protective frame 4, and FIG. 3A is a longitudinal sectional view taken along a cutting line along the vertical protective frame 4 passing through the central axis P of FIG. These are the side views seen from the right side of FIG. FIG. 3B shows a state in which the horizontal protective frame 3 and the vertical protective frame 4 are set on the joining jig 50. First, as shown in FIG. 3A, a guide shaft 51 is inserted through a pair of through holes 30 provided in the horizontal protective frame 3 and a pair of through holes 31 provided in the vertical protective frame 4. . The clearance between the guide shaft 51 and the through holes 30 and 31 is preferably as small as possible within the range in which the horizontal protective frame 3 and the vertical protective frame 4 can rotate. Through the guide shaft 51, the through hole 30 and the through hole 31 are arranged on a straight line. In this state, it is set on the joining jig 50.

  As shown in FIG. 3B, the horizontal protective frame 3 and the vertical protective frame 4 are joined in the groove 52 provided in the joining jig 50 with the guide shaft 51 inserted. The horizontal protective frame 3 is placed on the upper surface 53 of the joining jig 50. Since the groove 52 is formed at a right angle to the upper surface 53, the vertical protective frame 4 is orthogonal to the horizontal protective frame 3. In this state, the horizontal protective frame 3 and the vertical protective frame 4 are integrated by joining at positions A and B where the horizontal protective frame 3 and the vertical protective frame 4 intersect with each other by a joining means such as brazing. The Thereafter, the guide shaft 51 is pulled out. The joining jig may be arranged with right-angle blocks or the like on both sides of the vertical protective frame 4 in the figure.

(Assembling method of Earth Top 1)
Then, the assembly method of the earth top 1 is demonstrated, referring FIGS. 1-3. First, as a preparation step, as shown in FIG. 2 A, insert the bearing member 34 within the shaft hole 33 of the upper rotation shaft 20, by inserting the bearing member 42 to the shaft hole 35 of the lower rotary support shaft 21 deep. Moreover, the horizontal protective frame 3 and the vertical protective frame 4 are integrated by the joining method mentioned above. Then, the upper rotation support shaft 20 and the lower rotation support shaft 21 are screwed into the screw holes of the vertical protective frame 4. At this time, the distance between the upper rotation support shaft 20 and the lower rotation support shaft 21 is a distance in which the rotary disk 2 can be incorporated. Subsequently, the rotary disk 2 is inserted inside through the gap between the horizontal protective frame 3 and the vertical protective frame 4. Next, the rotation shaft portion 9 or the rotation shaft portion 10 is inserted into either the shaft hole 33 of the upper rotation support shaft 20 or the shaft hole 35 of the lower rotation support shaft 21. Then, the upper rotary support shaft 20 and the lower rotary support shaft 21 are rotated so that both of the rotary shaft portions 9 and 10 can be inserted into the shaft holes 33 and 35, respectively, so that the rotary disk 2 has a clearance along the central axis P. Is adjusted to a predetermined size.

At this time, the disk portion 5 of the rotating disk 2 is adjusted so as to have the same height as the horizontal protective frame 4. At this time, the position of the rotary disk 2 is adjusted in advance of the lower rotation support shaft 21 side, and then the clearance is adjusted on the upper rotation support shaft 20 side. This assembly order is for facilitating fine adjustment by forming a groove 36 at the tip of the upper rotation support shaft 20 and making this groove 36 a driver groove. However, the adjustment may be performed in the reverse order. The indentations 47 and 46 of the bearing members 34 and 42 are performed by the above-described forming method. However, the indentations 46 and 47 are also formed during use by the user, so if the user adjusts the clearance by rotating the upper rotation support shaft 20 (adjusting with screws) from time to time, It may not be formed in advance.

  In addition, when the rotating disk 2 is adjusted so that it can rotate stably, it is desirable to prevent the upper rotating support shaft 20 and the lower rotating support shaft 21 from easily rotating. For example, as shown in FIG. 1, the vicinity of the screwed portion of the upper rotation support shaft 20 of the vertical protective frame 4 is crushed and temporarily fixed (indicated by C in FIG. 1), and the vicinity of the screwed portion of the lower rotation support shaft 21 is Squeeze and temporarily fix (shown as D in FIG. 1). The temporary fixing means that the upper rotation support shaft 20 and the lower rotation support shaft 21 do not rotate in a normal use state and can be rotated at the time of adjustment.

  In the earth top 1 configured as described above, if the rotating disk 2 rotates at high speed, the direction of the rotation axis (rotation center axis P) is kept constant, and when an external force is applied, the direction of the force Thus, the so-called gyro effect in which the central axis P is inclined in the vertical direction is applied. Therefore, a tightrope can be stretched on a thin thread or wire, or can be rotated on a pointed member such as a pen tip.

The earth top 1 described above includes a disc portion 5, an upper core shaft portion 7, which is a first core shaft portion extending in the opposite direction from the disc portion 5 on the extension line of the central axis P of the disc portion 5, and the second core portion 7. This is a rotating disk 2 having a lower core shaft portion 8 as a core shaft portion, and a ring-shaped first protective frame arranged so as to surround the outer periphery of the disk portion 5 with a certain distance from the outer periphery. A horizontal protective frame 3 and a vertical protective frame 4 that is a ring-shaped second protective frame that is orthogonal to the horizontal protective frame 3 and is fixed to the horizontal protective frame 3 at crossing positions A and B with the horizontal protective frame 3; The upper rotation support shaft 20 and the second rotation support shaft, which are the first rotation support shafts that can move toward and away from the rotary disk 2 at respective top positions 180 degrees apart on the vertical protective frame 4. And a certain lower rotation support shaft 21. Conical pointed heads 45 and 44 are formed on the opposing tip portions of the upper core shaft portion 7 that is the first core shaft portion and the lower core shaft portion 8 that is the second core shaft portion. Bottom end shaft holes 33 and 35 are provided on the end surfaces 32 and 41 of the rotation support shaft 20 and the lower rotation support shaft 21 facing the core shaft portions 7 and 8, respectively. The shaft holes 33 and 35 are provided with resin bearing members 34 and 42 so that the coefficient of friction between the pointed head 45 of the upper core shaft part 7 and the pointed head 44 of the lower core shaft part 8 is reduced. Has been inserted. The rotary disk 2 is provided with an axial clearance between the pointed heads 44 and 45 and the bearing members 34 and 42.

  Since the earth top 1 configured in this manner receives a load in the direction of the central axis P (the weight of the rotating disk 2 is a main component) by the bearing member 34 or the bearing member 42 made of a fluororesin having a small friction coefficient, The friction loss is small, and the rotation of the rotating disk 2 can be maintained.

  The horizontal protective frame 3 as the first protective frame and the vertical protective frame 4 as the second protective frame are formed by cutting a metal pipe at right angles to the extending direction of the pipe. Both the frame 3 and the vertical protective frame 4 are provided with through holes 30 and 31 at two positions separated by 180 degrees, and the positions of the through holes 30 and the through holes 31 are aligned and joined so as to be orthogonal to each other. .

  It is not easy to manufacture a large-diameter horizontal protective frame 3 and a small-diameter vertical protective frame 4 which are two ring-shaped members, and to be orthogonally joined at an accurate position. In the present embodiment, the horizontal protective frame 3 and the vertical protective frame 4 are formed by cutting (slicing) a pipe that is a raw material, so that a thin ring shape can be accurately formed in a short time with respect to the outer diameter, Further, there are few cutting residues (chips and the like), and material waste can be saved. It should be noted that the horizontal protective frame 3 and the vertical protective frame 4 having high roundness and dimensional accuracy can be manufactured by rounding the pipe and then finishing at least the inner circumference (round processing). In the example shown in FIG. 3, the guide shaft 51 is passed through the through holes 30 and 31, and the horizontal protective frame 3 and the vertical protective frame 4 are joined orthogonally using a joining jig. The joining position and the joining angle with the vertical protective frame 4 can be managed with high accuracy.

In addition, the surface 34A of the bearing member 34 on the upper rotation support shaft 20 side which is the first rotation support shaft and the pointed portion 45 of the upper core shaft portion 7 which is the first core shaft portion abuts, and the second rotation support. An indentation imitating the shape of the top of each of the cusps is formed on the surface 42A of the bearing member 42 on the side of the lower rotation support shaft 21 that is the shaft, which contacts the cusp 44 of the lower core shaft 8 that is the second core shaft. 47 and 46 are formed.

When the center of gravity of the rotating disk 2 is on the bearing member 42 side, the tip 44 is supported by the indentation 46 of the bearing member 42, and when the center of gravity of the rotating disk 2 is on the bearing member 34 side, the indentation 47 of the bearing member 34 leaflet when supporting the head 45, while reducing the friction loss between the head 45 and 44 leaflet bearing member 34 and 42, (deflection in the radial direction perpendicular to the central axis P) lateral oscillation of the rotating disk 2 And the stable rotation of the rotating disk 2 can be maintained.

(Modification of bearing member)
FIG. 4 is a diagram illustrating a support structure of the upper core shaft portion 7 by the upper rotation support shaft 20 according to the modification of the embodiment described above. Since the support structure of the lower core shaft portion 8 by the lower rotation support shaft 21 is the same, the upper rotation support shaft 20 side will be described as an example. Note that components having the same configuration as the components shown in FIG. 2C are denoted by the same reference numerals as those in FIG. 2C . The upper rotation support shaft 20 is formed with a bottomed shaft hole 54 from the end portion 32 on the upper core shaft portion 7 side. A cylindrical bearing member 55 is inserted into the shaft hole 54. The bearing member 55 has a bottomed shaft hole 56 bored from the upper core shaft portion 7 side. The rotary shaft portion 9 of the upper core shaft portion 7 is inserted into the shaft hole 56. The radial clearance between the shaft hole 56 and the rotating shaft portion 9 is 0.02 mm to 0.05 mm. The bottom of the shaft hole 56 is a receiving surface 57 of the pointed head 45. The clearance in the direction along the central axis P of the rotating disk 2 is appropriately adjusted by the upper rotating support shaft 20 or the lower rotating support shaft 21 (see FIGS. 2A and 2B ).

The bearing member 55 is formed of a fluororesin or the like having a small friction coefficient with the upper core shaft portion 7. Examples of the fluororesin include polytetrafluoroethylene (PTFE). In addition to PTFE, polyacetal resin (POM) having a low coefficient of friction and high mechanical strength may be used. Examples of POM include copolymers and homopolymers. The bearing member 55 is formed into a bottomed cylindrical shape by cutting a fluororesin rod.

According to the configuration of the modified example, the rotary disk 2 is supported by the bearing member 55 on the upper core shaft portion 7 side having a small friction coefficient and the bearing member (not shown) of the lower core shaft portion 8. Accordingly, since both the central axis P direction and the radial direction are supported by the bearing member having a small friction coefficient, the core shaft 6 is oriented in the vertical direction, or is oriented in the horizontal direction or is inclined. However, friction loss can be reduced while suppressing rattling. Incidentally, the receiving surface 57, although not shown, the embodiment (FIG. 2 B, see Fig. 2C) is an indentation by cusp 45 described is formed.

(Modified example of the disk part 5 and the core shaft 6)
In the embodiment described above, the rotating disk 2 is formed by integrally forming the disk portion 5 and the core shaft 6 by cutting a metal bar. However, the disk portion 5 and the core shaft 6 can be separated. This will be described with reference to FIG.

FIGS. 5A and 5B are diagrams showing a modification of the disk portion 5 and the core shaft 6. FIG. 5A is a diagram showing a first modification, and FIG. 5B is a diagram showing a second modification. First, a first modification will be described with reference to FIG. The rotating disk 2 includes a disk part 5 and a core shaft 6. As shown in FIG. 5A, the disk portion 5 has a through hole 60 centered on the central axis P. A base portion 61 is provided at the center in the axial direction of the core shaft 6, and the base portion 61 is press-fitted and fixed in the through hole 60 of the disk portion 5. The base 61 is larger than the diameters of the upper core shaft portion 7 and the lower core shaft portion 8. By increasing the diameter of the base portion 61, the contact area with the inner wall of the through hole 60 is increased to increase the fixing force, and the base portion 61 is not inclined with respect to the disk portion 5. Incidentally, the base 61 may be substantially the same shape as the base portion 11 shown in FIG. 2 A. Further, one or both of the disk portion 5 and the core shaft 6 can be formed by cutting, or can be formed by molding.

  An example of a method for assembling the disk portion 5 and the core shaft 6 according to the first modification will be described. As shown in FIG. 5A, the disk portion 5 is placed on the die 64, the core shaft 6 is inserted into the through hole 60, and is pushed to a predetermined height position by the pushing jig 65. Although illustration is omitted, the die 64 is provided with a guide wall surrounding the outer periphery of the disk portion 2. Further, if a spacer (not shown) is interposed between the die 64 and the pushing jig 65, the accuracy of the pushing height of the core shaft 6 is increased.

  In the second modification, as shown in FIG. 5B, a thick portion 66 is provided in the disc portion 5. The thick portions 66 are provided on both the front and back sides of the disc portion 5. In addition, a through hole 60 centered on the central axis P is formed in the disk portion 5 (thick wall portion 66). The core shaft 6 is provided with a base 68 that is thicker than the diameters of the upper core shaft portion 7 and the lower core shaft portion 8 in the central portion in the axial direction, and the base portion 68 is press-fitted into the through-hole 60 to form the disk portion 5 and the core shaft. 6 is integrated. The method for assembling the disk portion 5 and the core shaft 6 according to the second modification is similar to the first modification, in which the disk portion 5 is placed on the die 64 and the core shaft 6 is inserted into the through hole 60, and the indentation treatment is performed. The tool 65 is pushed to a predetermined height position. Since the length of the base portion 68 is the same as the thickness of the thick portion 66, the base portion 68 may be pushed to a position where the end surface of the pushing jig 65 contacts the thick portion 66. Note that the thick portion 66 can have substantially the same shape as the base portion shown in FIG.

In the first and second modified examples described above, the rotating disk 2 includes the disk part 5 and the core shaft 6 that penetrates the central axis P of the disk part 5 as separate bodies. Against the above-described embodiment is the rotary disk 2 by (see FIG. 2 A), are formed integrally with the disc portion 5 and the Shinjiku 6 by cutting a metal rod, a first modification Then, since the disk part 5 is a disk with a constant thickness, it can be easily formed from a metal plate material, for example, by pressing. In a second variant, has the thick portion 66 in the center of the disc portion 5, it is possible to shorten much machining time for machining of the rotary disk 2 as shown in FIG. 2 A . Further, by making the disk part 5 and the core shaft 6 separate, the disk part 5 can be made of a material that is easy to process or a material that does not require heat treatment (for example, a copper-based alloy such as brass).

  Moreover, in the manufacturing method of the earth top 1 of the embodiment including the above-described modification, two kinds of metal pipes having different diameters are cut at right angles to the extending direction of the pipes, and the seamless diameter is obtained. Forming a ring of two different types, a step of processing the inner circumference of each ring into a substantially perfect circle, a large diameter ring of each ring as a horizontal protection frame 3 and a small diameter vertical protection frame 4, A step of providing through holes 30 and 31 at two positions 180 degrees apart in the horizontal protective frame 3 as the first protective frame and the vertical protective frame 4 as the second protective frame; And aligning the positions of the through-holes 30 and 31 and joining them so as to be orthogonal to each other.

  Since the horizontal protective frame 3 and the vertical protective frame 4 are formed by cutting (slicing) a pipe as a raw material, a thin ring shape can be accurately formed in a short time with respect to the outer diameter. Further, there are few cutting residues (chips and the like), and material waste can be saved. It should be noted that the horizontal protective frame 3 and the vertical protective frame 4 having high roundness and high dimensional accuracy can be easily manufactured if at least the inner periphery is finished (round processing) after the pipe is cut.

  It should be noted that the present invention is not limited to the above-described embodiment including the modifications, and includes modifications and improvements as long as the object of the present invention can be achieved. For example, in the above-described embodiment, the rotary shaft portions 9 and 10 are provided on the rotary disk 2 side, and the shaft holes 33 and 35 are provided on the upper rotary support shaft 20 side and the lower rotary support shaft 21 side, respectively. Holes corresponding to the shaft holes 33 and 35 are provided in the upper core shaft portion 7 and the lower core shaft portion 8 on the rotary disk 2 side, and the rotation shaft portions 9 and 10 are provided on the upper rotation support shaft 20 and the lower rotation support shaft 21 side. Corresponding holes may be provided.

  In the above-described embodiment, the earth top 1 has the two string winding holes 12 and 13, but only one of the two may be used. In the embodiment described above, the horizontal protective frame 3 has a larger diameter than the vertical protective frame 4, but the size may be reversed. Further, it is preferable that the string used has a hardened tip using an adhesive such as cemedine. The length of the tip to be hardened is preferably in the range of 0.5X to 3X, and more preferably in the range of X to 2X, where X is the diameter of the core shaft 6 where the through holes 30 and 31 are provided. When applying an adhesive such as cemedine, it is preferable to loosen the end of the string so that the adhesive sufficiently enters the inside of the string, and then solidify into a columnar shape. Moreover, it is good for a string to make it a shape which becomes thin as it goes to a front-end | tip so that it may enter into the through-holes 30 and 31 easily. When forming this gradually narrowing portion, the length is preferably in the range of 0.7X to 1.5X. For example, if the diameter of the core shaft 6 in the portion where the through holes 30 and 31 are provided is 5 mm, the length of the tip portion that is hardened using an adhesive such as cemedine is 10 mm, and the length of the portion that becomes gradually thinner Is considered to be 3.5 to 7.5 mm.

  In the embodiment described above, the large-diameter horizontal protective frame 3 and the small-diameter vertical protective frame 4 are joined by brazing or the like, but the through hole 31 of the inner vertical protective frame 4 is a screw hole, The horizontal protective frame 3 may be fixed to the vertical protective frame 4 with a countersunk screw or the like. Alternatively, both the through hole 31 of the vertical protective frame 4 and the through hole 30 of the horizontal protective frame 3 may be screw holes, and may be fixed with a screw screw having no screw head. In this case, it is preferable not to loosen the screw with a screw adhesive or the like.

1 ... Earth top 2 ... Rotating disk 3 ... Horizontal protective frame (first protective frame)
4 ... Vertical protective frame (second protective frame)
5 ... Disk part 6 ... Core shaft 7 ... Upper core shaft part (1st core shaft part)
8 ... Lower core shaft portion (second core shaft portion)
20 ... Upper rotation support shaft (first rotation support shaft)
21 ... Lower rotation support shaft (second rotation support shaft)
30, 31 ... Through hole 33 ... Shaft hole 34 ... Bearing member 35 ... Shaft hole 42 ... Bearing member 44, 45 ... Pointed head 46, 47 ... Indentation 55 ... Bearing member 56 ... Shaft hole 57 ... Receiving surface

Claims (5)

A rotating disk having a disk part, and a first core shaft part and a second core shaft part extending in opposite directions from the disk part on an extension line of the central axis of the disk part;
A ring-shaped first protective frame disposed so as to surround the outer periphery of the disk portion with a certain distance;
A ring-shaped second protective frame that is orthogonal to the first protective frame and is fixed to the first protective frame at an intersection with the first protective frame;
A first rotation support shaft and a second rotation support shaft that are movable in a direction approaching or moving away from the rotating disk at respective top positions 180 degrees apart of the second protective frame;
Have
A conical pointed head is formed at each tip portion of the first core shaft portion and the second core shaft portion facing each rotation support shaft,
A bottomed shaft hole is provided on each end face of each of the first rotation support shaft and the second rotation support shaft facing the core shaft portions,
In the shaft hole, a resin bearing member having a small friction coefficient with the first core shaft portion and the second core shaft portion is inserted,
The rotating disk is provided with an axial clearance between the pointed head and the bearing member.
Earth top characterized by that. In the earth top according to claim 1,
The first protective frame and the second protective frame are each seamless.
The first protective frame and said second protective frame are both has a through hole at two positions 180 degrees apart, both the through hole of the same position,
Earth top characterized by that. In the earth top according to claim 1 or claim 2,
The bearing member is softer than the first core shaft portion and the second core shaft portion,
The surface of the first core shaft portion of the bearing member on the first rotation support shaft side that the pointed portion hits, and the second core shaft portion of the bearing member on the second rotation support shaft side. wherein the surface on which cusp hits of, and as indentations conforming to the top shape of the peak portion each formed,
Earth top characterized by that. In the earth top of any one of Claims 1-3,
The bearing member has a shaft hole that regulates the radial position of the rotating disk, and a receiving surface that regulates the position of the rotating disk in the central axis direction at the bottom of the shaft hole.
Earth top characterized by that. In the top of the earth according to any one of claims 1 to 4,
The rotating disk includes a disk portion and a core shaft that passes through a central axis of the disk portion, and one end of the core shaft is the first core shaft portion, and the other end of the core shaft is the second shaft. The core shaft part of
Earth top characterized by that.

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