JPH05307383A - Drum - Google Patents

Abstract

PURPOSE:To provide the drum having high durability, which can raise head tension, and also, can execute easily positioning of a tightening bolt to a head tightening nut, and generates no damage with regard to their screw parts. CONSTITUTION:To both ends of a cylindrical barrel main body 11, suspension rings 12, 13 are attached fixedly. These rings 12, 13 are connected by a support 31. Openings 14, 15 of these rings 12, 13 are covered with drum heads 16, 17. By screwing a bolt 22 into a lug nut 23, outside peripheral edges 16A, 17A of the drum heads 16, 17 are inserted and pressed between tightening frames 19, 20 and collars 12A, 13A of the rings 12, 13. The bolt 22 is inserted through an insert-through hole 21 of the tightening frames 19, 20, and on the other hand, the lug nut 23 is fitted loosely into the insert-through hole of the rings 12, 13. At the time of screwing the bolt 22 into the lug nut 23, an automatic aligning function works, and they are screwed exactly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drum, and more specifically, by adding a self-aligning function to a bolt and a nut for tensioning a drum head, the position of the bolt and the nut can be easily aligned and the screw portion thereof It is intended to prevent damage.

[0002]

2. Description of the Related Art Conventional drums include those disclosed in U.S. Pat. No. 4,869,146.
In this drum, a hoop for attachment is fixed to one end of a drum body, a drum head is stretched on the hoop, and an outer peripheral edge of the drum is held by a head holding hoop. The head holding hoop is fixed to the mounting hoop with a plurality of bolts. A drum head is directly stretched on the other end (bottom side) of the drum body, and the outer peripheral edge of the drum head is pressed by a hoop for bottom. The hoop for mounting and the hoop for bottom are connected by a plurality of screw-in type rods and a pair of bolts. In this case, the positions of the rod and the bolt in the circumferential direction of the drum body are set to be offset from the position of the fixing bolt of the head pressing hoop.

[0003]

However, in such a conventional drum, since the mounting hoop is connected to the bottom hoop by the rod, the screw fixed to the mounting hoop is fixed. It is difficult to accurately position and screw the bolt against the bush, especially when tightening the bolt and adjusting the tension of the drum head, it is necessary to repeatedly retighten the bolt, so it is misaligned in these positions. If such a problem occurs, there is a problem that the screw part such as a bolt is damaged.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a highly durable drum in which the tightening bolts can be easily positioned with respect to the head tightening nut and the threaded portions thereof are not damaged. I am trying.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a cylindrical drum body, a pair of rings fixed to both ends of the drum body to define openings, and at least one of the openings are covered. A drum head, a tightening frame for pinching the peripheral portion of the drum head between the drum head, a bolt and a nut for fixing the tightening frame to the ring by screwing, and a connecting member for connecting the pair of rings. When,
In the drum provided with, the bolt and the nut are drums having an automatic centering function when they are screwed together.

[0006]

According to the present invention, the bolts and nuts for fixing the fastening frame to the ring exert the self-centering function when they are screwed together. That is, in order to stretch the drum head, the opening of the ring is covered with the drum head, and the peripheral edge of the drum head is clamped between the ring and the ring by the tightening frame.
At this time, the tightening frame is fixed to the ring while pressing the drum head by screwing the bolt into the nut.
When the bolt is screwed into the nut, the bolt and the nut are positioned coaxially by the self-aligning function and they are screwed together. As a result, the screw portions will not be damaged.

[0007]

EXAMPLES A drum according to the present invention will be described below based on examples. 1 and 2 are views for explaining an embodiment of the present invention.

As shown in these figures, suspension rings 12 and 13 as flanged rings are fitted to each end of a body 11 made of a cylindrical body having open ends. These suspension rings 12, 13 respectively define circular openings 14, 15 which are covered by drum heads 16, 17, respectively. Collars 12A and 13A, which project outward in the radial direction, are provided on the base ends of the suspension rings 12 and 13 (on the side where they are fixed to the body 11). That is, these collars 12A and 13A are the body 1
1 protrudes radially outward from the outer peripheral surface of the body 1 by a predetermined length, and these extend in the axial direction of the body 11 of the body 11.
Are arranged so as to face each other at intervals of the length. Then, a plurality of through holes 18 are arranged in the collars 12A and 13A at equal intervals along the circumferential direction.
Each of these through holes 18 is formed so as to extend in the axial direction of the body 11, and its cross section is circular and has a predetermined diameter. In addition, the body 1 of these through holes 18
A step 18A is formed in the opening on the first side.

The inner peripheral surfaces of the opening ends of the suspension rings 12 and 13 are formed in a tapered shape, and the drum heads 16 and 17 are provided with tightening frames (hoops) 19 and 20 so as to cover the openings 14 and 15. It is stretched. That is, the outer peripheral edges 16A of the drum heads 16 and 17,
17A is formed of an annular body, and this annular outer peripheral edge 1
6A and 17A are also provided with annular fastening frames 19 and 20 from the outer side in the axial direction with respect to the body 11 to the brim 12A,
By pressing and urging each toward 13A,
The drum heads 16 and 17 are stretched in a tensioned state. Therefore, the inner peripheral surfaces of the fastening frames 19 and 20 are in contact with the outer peripheral edges 16A and 17A. Even in these tightening frames 19 and 20, a plurality of insertion holes 21 extending in the same direction as the axis of the through hole 18 are provided corresponding to the through hole 18 and at equal intervals in the circumferential direction. Formed and arranged.

Then, the bolts 22 and lug nuts 23 for tensioning the drum heads 16 and 17 for urging the fastening frames 19 and 20 toward the flanges 12A and 13A of the suspension rings 12 and 13, respectively, are respectively inserted into the through holes. 21 and the through hole 18 are inserted and held.
That is, a lug nut 23 having a flange 23A at one end is provided in each through hole 18, and the flange 23A is provided with a step 18
It is inserted in contact with A. The lug nut 23 is attached to the brim 12 by the C-ring 24 for retaining.
It is retained in the through hole 18 by being locked to the surface of A and 13A opposite to the step 18A. Further, since the outer diameter of the lug nut 23 is formed smaller than the diameter of the through hole 18 by a predetermined value, the lug nut 23 is held by the flanges 12A and 13A while being loosely fitted in the through hole 18. Since the lug nut 23 is configured as described above, the lug nut 23 can be tilted while being inserted and retained in the through hole 18. More specifically, the lug nut 23 has a predetermined gap with the inner peripheral surface of the through hole 18 so that the axis of the lug nut 23 can be inclined within a predetermined angle range with respect to the axis of the through hole 18. It is fitted loosely. Further, in order to make the lug nut 23 inclinable in this way, the contact surface of the flange 23A with the step 18A may be formed as a curved surface.

On the other hand, the bolt 22 screwed into the lug nut 23 has its shaft portion inserted through the insertion holes 21 of the fastening frames 19 and 20 and attached to the fastening frames 19 and 20. Therefore, these bolts 22 are formed so that they can be screwed into the lug nut 23, and when the bolt 22 is screwed into the lug nut 23, the drum head 1
The outer peripheral edges 16A and 17A of 6 and 17 can be pressed and urged toward the flanges 12A and 13A of the suspension rings 12 and 13. In addition, in FIG.
A sound ray 25 is stretched in contact with the surface of the drum head 17. Reference numerals 26 and 27 are snare strainers for tensioning the sound ray 25. These snare strainers 2
6 and 27 are fixed to the collar 13A of the suspension ring 13. In addition, the suspension ring 12,
The columns 13 are connected by a plurality of columns 31. That is, a plurality of columns 31 (for example, aluminum rods) are arranged between the collars 12A and 13A, and both ends of these columns 31 are fixed to the collars 12A and 13A by screws 32, respectively. A plurality of columns 31 are arranged at equal intervals in the circumferential direction of the suspension rings 12, 13. In addition, the connecting positions of the columns 31 of the collars 12A and 13A are set at positions deviated from the forming positions of the through holes 18. The pillars 31 may have any shape such as a pipe shape, a shaft shape, and a spoke shape, as long as they have a predetermined rigidity when connecting the suspension rings 12 and 13. The number of columns 31 is also arbitrary.
Furthermore, as the material of the support column 31, carbon fiber, titanium or the like is preferable. This is because weight reduction can be achieved.

In the snare drum having the above structure,
The drum heads 16 and 1 are inserted into the openings 14 and 15 of the suspension rings 12 and 13 connected by a plurality of columns 31.
In order to tension each of the seven, the bolts 22 are screwed into the lug nuts 23, and the outer peripheral edges 16A and 17A of the drum heads 16 and 17 are connected to the brim 12A via the tightening frames 19 and 20.
Energize toward 13A. In this case, the bolts 22 are inserted into the insertion holes 21 of the tightening frames 19 and 20, and the tip ends of the shafts thereof are the flanges 12 of the suspension rings 12 and 13.
The screw holes of the lug nuts 23 attached to A and 13A are engaged. Then, when the bolt 22 is screwed in, the lug nut 23 is loosely fitted in the through hole 18 as described above, so that the bolt 22 and the lug nut 23 are exactly coaxial with each other at the beginning of screwing due to the self-aligning action. Even if it is not, the lug nuts 23 are inclined according to the progress of screwing, and these are arranged coaxially and screwed accurately. As a result, the bolt 22 and the lug nut 23 do not exert an unreasonable force on their threaded portions, and there is no possibility of damaging them. Further, since it has the self-aligning function, the tightening force does not increase only in the specific bolts 22 and the lug nuts 23 in the circumferential direction in this drum, and the tightening force acts on average as a whole. Become. Therefore, a part of the open end portions of the suspension rings 12 and 13 having a small wall thickness is not deformed or damaged. As a result, the drum heads 16, 1
It is possible to further increase the tension of 7.

Further, in the drum according to the above-mentioned embodiment, since the plurality of bolts 22 are all arranged in the axial direction and the heads thereof are exposed on the openings 14 and 15 side, the bolts 22 are provided. There is no member that interferes when screwing in, and the tuning work of the tightening force of these bolts 22 can be easily performed. In addition, since the mounting hardware and the like are not fixed to the body 11 of the body, a good vibration state can be obtained. Furthermore, the suspension ring 12,
Since the 13 parts are firmly connected by the support column 31,
The tightening force by the bolt 22 can be increased, and the drum head 16,
The tension of 17 can be further increased. At this time, the number of columns 31 is reduced regardless of the number of bolts 22, the columns 31 are spoke-shaped, and the columns 31 are made of aluminum or the like, so that the drum head 1
The weight of the drum as a whole can be reduced with the tensions of 6 and 17 increased. Further, the suspension rings 12 and 13 and the body 11 can be made of various materials in combination. The former is a lightweight and highly rigid one such as carbon fiber, aluminum or titanium, the latter is a carbon fiber, Those having excellent acoustic characteristics such as maple, birch and spruce are preferable. In addition,
These body 11 and suspension ring 12,
It is also possible to integrally form 13 with carbon fiber or the like. Further, in the above embodiment, the body 11
Although the case where the drum heads 16 and 17 are stretched at both ends of the above is described, the present invention can of course be applied to a one-head drum in which the drum head is stretched at either one of the openings. Further, the present invention is suitable for marching drums that are required to be lightweight and have improved head tension.

[0014]

According to the present invention, the tension of the drum head can be increased, and when the bolts are screwed into the nuts, they can be easily aligned with each other. Can be prevented.

[Brief description of drawings]

FIG. 1 is a front view showing a drum according to an embodiment of the present invention with a part thereof cut away.

FIG. 2 is a sectional view showing a member for tensioning a drum head according to an embodiment of the present invention.

[Explanation of symbols]

11: body, 12, 13: suspension ring, 1
4, 15: Opening, 16, 17: Drum head, 22: Bolt, 23: Lug nut, 31: Strut

Claims (1)

[Claims] 1. A cylindrical drum body, a pair of rings fixed to both ends of the drum body to define openings, a drum head covering at least one of the openings, and a drum head of the drum head. A drum provided with a tightening frame for pinching the peripheral portion between the ring, a bolt and a nut for fixing the tightening frame to the ring by screwing, and a connecting member for connecting the pair of rings. The above-mentioned bolt and nut have a self-centering function when they are screwed together.