JPH09230856A - Music box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prohibit the movement of the other end of a mainspring and to obtain a music box having good tone by forming a contact part for prohibiting the movement of the other end of the mainspring held engaged with an engaging part toward the outer direction of a barrel drum. SOLUTION: The outside end 2b which is the other end of the mainspring 2 projects outward of a mainspring housing section and constricted parts 49 are formed. The constricted parts 49 are hooked and stopped to the engaging parts 50 which are formed at a case 8 and a frame 1 and are arranged on the frame 1. A barrier wall 55 as the contact part to be pressed to the front end of the outside end 2b of the mainspring 2 is extended and formed at a pedestal 57 in a direction orthogonal with the side plate mounted with a diaphragm. Then, even if the friction force between the mainspring 2 and the mainspring housing part changes, the movement of the outside end 2b in the outward direction of the barrel drum is surely limited by the barrier wall 55 and the release of the energized mainspring 2 is smoothly effected. In addition, the striking sounds with the engaging parts by the movement of the outside end 2b are decreased and noise is lowered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a music box using a mainspring as a drive source for a drum.

[0002]

2. Description of the Related Art A mainspring used as a drive source of a music box drum is housed in a state called a barrel, which is composed of a frame and a case of a music box and wound around a winding shaft. This spring has one end inserted into the winding shaft protruding into the barrel and locked from the outside of the barrel, and the other end hooked on the engaging portion formed on the outer peripheral wall of the barrel. The end is designed not to get inside the barrel. At the other end of the mainspring hooked on the engaging portion, a necked portion called necking hooking on the engaging portion is formed. The constricted portion is formed with a play in the mainspring extending direction with the engaging portion in consideration of workability at the time of winding the mainspring and engaging the other end. Then, the mainspring in the barrel is wound around the winding shaft in a spiral shape and charged, and from that state is gradually released by the action of the speed control means to rotationally drive the drum to make a tune play.

[0003]

However, when the mainspring is released, the frictional force (first frictional force) between the outermost peripheral surface of the mainspring and the inner peripheral surface of the barrel, and the second outermost peripheral surface and the second innermost coil located inside thereof. If the relationship with the frictional force (second frictional force) with the outer peripheral surface is broken, the mainspring may not be released smoothly, and the other end hooked on the engaging portion may move in the direction of popping out of the barrel. In such a state, a tapping sound may be generated between the other end of the mainspring and the engaging portion, which may be one factor of noise during playing.

The relationship between the first frictional force and the second frictional force is always
If it is configured such that “first friction force> second friction force”,
Although the mainspring can be released smoothly and such a problem does not occur, it is difficult to maintain the frictional force in the above-mentioned relationship, which requires a lot of trial and error and is poor in reliability. This consumes a lot of time in product development and causes a rise in product cost. The present invention
The purpose of the present invention is to reliably prevent the movement of the other end of the mainspring to provide a music box with good sound quality.

[0005]

In order to achieve the above object, the present invention provides one end of a mainspring which is a rotary drive source of a drum which is surrounded by a barrel and plays a tune by playing a diaphragm.
It is locked to the winding shaft arranged in the barrel, the other end of the mainspring is engaged with the engaging portion provided on the frame, and the frame is
An abutting portion that prevents the other end of the mainspring in the engaged state from moving toward the outside of the barrel is formed in the engaging portion.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In a music box according to the present invention,
A drum that plays a song by playing a vibrating plate with a comb-like vibrating valve, a mainspring that serves as a rotational drive source for the drum, a barrel that surrounds the mainspring, and a speed control means that controls the rotational speed of the drum are supported on the frame. Then, one end of the mainspring is locked to the winding shaft arranged in the barrel and the other end is engaged with the engaging portion provided on the frame. In this way, the contact portion that blocks the movement of the other end of the mainspring engaged with the engagement portion in the outward direction of the barrel is formed on the frame that supports the components of the music box. Therefore, even if the frictional force applied to the mainspring changes and the other end of the mainspring tries to move toward the outside of the barrel, the movement is hindered by the contact portion formed on the frame.

[0007] When the engaging portion is provided with a restricting member for restricting the movement of the end of the mainspring inward of the barrel against the winding force applied to the winding shaft, the movement of the other end of the mainspring inward of the barrel is restricted. As a result, the movement of the other end of the mainspring is reduced.

The type of music box may be one in which a drum rotation axis is vertically arranged on a frame and a pedestal for mounting a vibration plate is erected on the frame. The pedestal of the music box includes the pedestal and the frame. The contact portion may be formed by protruding in an L-shape so as to be connected to. By providing the abutting portion in this way, the pedestal is increased by the mass of the abutting portion and the strength of the pedestal with respect to the frame is increased, so that the vibration from the vibration valve is efficiently transmitted to the frame.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. In the music box shown in FIGS. 1 and 2, a mainspring 2 and a winding shaft (hereinafter referred to as a “winding shaft”) 3 are arranged substantially at the center of a frame 1, and drums 4 and a plurality of combs are provided at four corners around the frame 1. A vibrating plate 5 having a tooth-shaped vibrating valve 5a, a speed increasing wheel train 6 serving as speed adjusting means, and a braking means 7 are arranged. The mainspring 2, the winding shaft 3, the speed increasing train wheel 6 and the like are
It is substantially covered by a case 8 attached to the frame 1.

The operation of the entire music box will be briefly described. The mainspring 2 wound around the winding shaft 3 rotates the winding shaft 3 by releasing the stored force, and rotates the first gear 12 which is a part of the speed increasing train 6 and is integral with the winding shaft 3. The drum 4 is rotationally driven via the pinion 10 integrated with the drum 4. The rotation of the drum 4 causes the vibrating valve 5a to play a tune. Further, the rotation of the first gear 12 is increased in speed through the speed increasing train wheel 6 and transmitted to the braking means 7, and the friction of the braking means 7 adjusts the rotation of the drum 4 so that the rotation of the drum 4 does not excessively increase. ing.

The frame 1 is made of a metal such as a zinc alloy and has a substantially square planar shape. The frame 1 is provided with mounting holes 37 and 38, and the music box is mounted to the resonance member by inserting screws or the like (not shown) into the mounting holes 37 and 38 and tightening the screws into a resonance member (not shown). The resonance member is made of, for example, wood, metal, glass, or the like.
The hole indicated by reference numeral 39 is a mounting portion for mounting a stopper or the like (not shown).

The frame 1 has a pin 4 for caulking which is inserted into mounting holes 40, 41, 42 and 43 provided in the case 8.
0a, 41a, 42a, 43a are formed so as to project upward, and after inserting each pin into each mounting hole, the head of the pin is crushed to fix the case 8 to the frame 1. Here, the case 8 is made by caulking each pin.
The frame 1 is integrated with the frame 1, but screw holes may be used instead of the pins by providing screw holes.

The case 8 is made of synthetic resin, and has a mainspring housing portion 61 forming a barrel for accommodating the mainspring 2, a gear housing portion 62 surrounding the speed increasing gear train 6, and a drum 4 rotatably between the frame 1. A fixed wall portion 60 and the like for integrally supporting the drum bearing portion 9 and the rotating body 70 of the braking means 7 that are brought into sliding contact with each other to brake the speed increasing train wheel 6 are integrally formed. In addition,
The molding parts such as the mainspring housing portion 61, the gear housing portion 62, the drum bearing portion 9, and the fixed wall portion 60 may be molded separately or partially separately to be integrated on the frame 1.

The drum 4 is arranged at one corner of the frame 1 so as to stand vertically with respect to the frame 1. The drum 4 is rotated around a vertical center of rotation by the frame 1 and a drum bearing portion 9 protruding from the case 8 in parallel therewith. It is rotatably supported by. As shown in FIG. 3, the drum 4 has a cylindrical portion 4a in which a pin 4d for flipping the vibration valve 5a is planted on the peripheral surface, and an upper end plate 4b that closes one end of the cylindrical portion 4a to form a bearing portion. The lower end plate 4c integrally includes a pinion 10 that meshes with a first gear 12 provided on the winding shaft 3 and an output gear 11 that takes out a driving force to a movable member (not shown).

In the drum 4, the upper end plate 4b and the lower end plate 4c are directly press fitted to each other to integrate the entire drum. That is, from the upper end plate 4b and the lower end plate 4c, sleeves 4f and 4g for press-fitting inward are respectively provided.
Are integrally molded, and both end plates 4b and 4c are projected.
Both end plates 4b, 4c and the tubular portion 4a are joined and integrated by sandwiching the tubular portion 4a and press-fitting the sleeves 4f and 4g. As a result, it is possible to prevent the lower end plate 4c from idling at the time of playing, and the drum rigidity is increased and the sound is improved.

In this drum 4, a shaft portion 4e integrally formed with a lower end plate 4c is supported by a drum shaft support hole 18 formed in the frame 1, and an upper end plate 4b is downward from a drum bearing portion 9 integral with a case 8. It is rotatably supported by being fitted with the shaft portion 19 protruding inward. The drum shaft support hole 18 has a tapered hole 18A at the opening on the lower end plate 4c side of the drum 4, and a tapered shoulder portion 18 formed on the shaft portion 4e of the lower end plate 4c.
It is provided to receive and support B. A recess 20 for accommodating the pinion 10 portion is formed in the frame 1 around the drum shaft support hole 18, and the recess 20 is one step lower than the frame upper surface 1a to suppress the height in the vicinity of the drum.

Between the drum bearing portion 9 and the upper end plate 4b,
A spring member 22 that urges the drum 4 in the axial direction is interposed, presses the drum 4 against the tapered hole 18A of the frame 1, and imparts a constant braking force to the drum 4. The spring member 22 has the cylindrical shaft portion 19 formed on the inner side of the drum bearing portion 9 and the upper end plate 4 of the drum 4.
The drum 4 is rotatably supported by being inserted into the hole 21 of b. Here, a disc spring is used as the spring member 22, but the spring member 22 is not limited to this. The frame 1'in the vicinity of the output gear 11 is formed to be slightly larger than the outer diameter of the gear 11 to prevent the output gear 11 from being damaged when the music box falls.

The winding shaft 3 of the mainspring 2 penetrates through the frame 1 at substantially the center of the frame 1 and the mainspring housing portion 61.
It is arranged inside and is rotatably supported by the case 8 and the frame 1. More specifically, as shown in FIG. 4B, the upper end 3a of the winding shaft 3 is attached to a boss portion 46 provided eccentrically from the central portion of the mainspring housing portion 61 so as to be substantially at the center of the frame 1. Perforated bearing part 4
7, the lower end 3b penetrates the bearing portion 23 formed in the frame 1 and projects to the outside of the frame 1. As shown in FIGS. 3 and 5, a threaded portion 3c is provided on the lower end 3b of the winding shaft 3 protruding outside the frame 1, and a winding key (not shown) or a base (not shown) that is a substitute thereof is usually attached. To be In the center of the winding shaft 3, as shown in FIG.
As shown in (B), the inner end 2a, which is one end of the mainspring 2,
A spring stopper pin 29 for locking the spring is provided so as to project in the radial direction. A hole 2c is formed in the inner end 2a of the mainspring 2.
The spring 2 is wound into the spiral spring housing 61 by hooking the spiral spring fixing pin 29 in the hole 2c and rotating the winding shaft 3 in the winding direction.

Like the pinion 10 of the drum 4, the No. 1 gear 12 connected to the winding shaft 3 is housed in a recess which is lower than any other portion of the frame 1 and has a bearing hole 2 in the frame 1.
It is rotatably supported by a convex portion 48 formed around 3. The mainspring 2 is arranged above this.

The winding shaft 3 and the first gear 12 are the ratchet 2
It is connected via 4 so that rotation is transmitted only in one direction. For example, as shown in FIG. 4A, the ratchet 24 has a substantially S-shaped planar shape, and the annular portion 2 at the center portion.
4a is fitted so as to engage with the winding shaft 3 only in the rotational direction. Here, the inner peripheral surface of the annular portion 24a has 90
The recesses 25 are formed at every 90 ° so as to engage with the protrusions 26 formed at every 90 ° on the outer peripheral surface of the winding shaft 3 only in the rotational direction, and the winding shaft 3 and the ratchet 24 are provided so as to rotate integrally. There is. The arcuate elastic arms 24b of the ratchet 24 are formed symmetrically at opposite positions, and the tip end thereof has the first gear 1
A claw portion 27 that engages with the claw portion 28 formed on the inner peripheral surface of the second boss portion in only one direction is provided. The claw portion 28 has a tooth surface in the normal direction that engages with the claw portion 27 in the counterclockwise rotation direction of the ratchet 24, and in the clockwise rotation direction of the ratchet 24, the elastic arm 24b is deformed inward to deform the claw portion. An inclined surface is provided to prevent 27 from passing over the pawl portion 28 and transmitting rotation.

The outer end 2b which is the other end of the mainspring 2 is shown in FIG.
As shown in FIG. 5, a constricted portion 49 that protrudes outside the mainspring housing portion 61 and is called necking is formed as shown in FIGS. The constricted portion 49 is hooked and fixed to an engaging portion 50 formed on the case 8 and the frame 1 and arranged on the frame 1.

The engaging portion 50 is composed of a lateral rib 51 integrally formed on the upper surface 1a of the frame 1 and a protruding portion 52 formed on the rear surface 8a of the case 8, both of which are attached to the winding shaft 3. The outer end 2b of the mainspring 2 against the winding force.
It constitutes a restricting means for restricting the movement in the inward direction of the barrel. As shown in FIG. 7, the lateral ribs 51 and the protrusions 52 are formed to have a width smaller than the width W of the constricted portion 49.
Can be smoothly engaged with. Further, in the vicinity of the lateral rib 51, the protrusion 52 and the back surface 8 a of the case 8 are provided.
Vertical ribs 53 and 54 are provided for mounting.

In the vicinity of the engaging portion 50, a pedestal 57 for mounting the vibration plate 5 is provided so as to vertically project from the upper surface 1a of the frame 1. The diaphragm 5 has a base 57 as shown in FIGS.
Is fastened to the side wall 57a of the frame with a fastening member such as a screw 58, and is arranged vertically to the frame 1 and laterally like the drum 4. Therefore, the occupied plane area of the diaphragm 5 with respect to the frame 1 is set to be approximately the plate thickness. The vibrating plate 5 is fixed to the pedestal 57, and is arranged such that the tip of the vibrating plate 5 is engaged with the pin 4d of the drum 4 and substantially overlaps with the rotation center axis of the drum 4. The vibrating valve 5a is repelled at a certain portion. The vibrating plate 5 is fixed to the pedestal 57 with its treble side closer to the frame 1, and accordingly, the drum 4 also has its treble side near the frame 1 and its bass side drum. It is arranged so as to be on the bearing portion 9 side.

The pedestal 57 has a cantilevered support structure integrally formed with the frame 1 by casting or the like, and the horizontal ribs 51 and the vertical ribs 53, 54 described above are integrally formed with the lower portion 57b thereof. The pedestal 57 has a side plate 5 to which the diaphragm 5 is attached.
A barrier 55 as an abutting portion that abuts the tip 2b1 of the outer end 2b of the mainspring 2 is formed to extend in a direction orthogonal to 7a. As shown in FIG. 7, the barrier 55 is integrally formed by projecting from the lower portion 57 b of the pedestal 57 toward the upper portion 57 c in an L-shape connected to the frame 1.
The rigidity of the pedestal 57 is increased by increasing the thickness of the lower side of the pedestal 57. The barrier 55 is arranged outside the engaging portion 50.

A space 59 is formed between the inner surface 55a of the barrier 55 and the outer surface 51a of the lateral rib 51, and the width W1 thereof is set to be smaller than the width from the tip 2b1 of the outer end 2b to the constricted portion 49. Has been done. Therefore, when the outer end 2b of the mainspring 2 is arranged in the space 59, it is sandwiched by the lateral ribs 51 and the barrier 55, and prevents the outer end 2b shown by the arrow B from moving in the outward direction of the barrel. In addition, this width W
1 may be set larger than the width from the tip 2b1 to the constricted portion 49. In any case, the barrier 55 is the tip 2
It is arranged on the arrow B direction side of b1.

An opening 56 is formed between the barrier 55 and the case 8 as shown in FIGS. As shown in FIG. 2, the opening 56 has a mainspring housing portion 61.
It is in communication with the mainspring housing part 6 of the mainspring 2.
It is an insertion slot for 1.

The mainspring housing portion 6 of the mainspring 2
The winding into the inside 1 is performed by using the winding shaft 3 after the assembling of the music box is completed. That is, the inner end 2a of the mainspring 2 is inserted through the opening 56 and locked to the pin 29 of the winding shaft 3, and a mechanically strong winder or the like is used to prevent the inner end 2a from coming off with a mechanically strong torque. Tighten the mainspring 2. As the winding of the mainspring 2 progresses, the outer end 2b becomes the opening 5
6, the outer end 2b is pushed toward the locking portion 50, the protrusion 52 and the lateral rib 51 are engaged with the constricted portion 49, and the outer end 2b is moved as shown in FIG. Insert in the space 59. Then, the tip 2b1 is held in the space 59 in contact with the barrier 55 or in a separated state according to the setting state of the width W1.

Therefore, even if the frictional force between the mainspring 2 and the mainspring housing portion 61 is changed as in the conventional case, the barrier 55 is arranged in the outward direction of the barrel as indicated by the arrow B, and therefore the outer end 2b is formed by the barrier 55. The movement in the outside direction (direction of arrow B) of the barrel is surely restricted. Therefore, the spring 2 thus stored can be released smoothly, and the hitting sound with the engaging portion 50 due to the movement of the outer end 2b can be reduced, resulting in a music box with less noise. Further, since there is no need for many trial and error unlike the method of adjusting the frictional force, the time for product development can be reduced and the product cost can be reduced.

In addition, since the engaging portion 50 restricts the movement of the barrel 2 in the inward direction as indicated by the arrow A, the outer end 2b hardly moves, so that the mainspring 2 can be released more smoothly and reliably. The hitting sound with the engaging portion 50 can be further reduced.

Further, since the barrier 55 is projectingly provided in an L-shape on the pedestal 57 so as to be connected to the frame 1 at the lower end 57b side, the mass of the lower part of the pedestal 57 is increased and the rigidity is increased, so that the pedestal 57 is formed. A large amount of vibration from the low-pitched sound side of the diaphragm 5 located on the upper side 57c side is transmitted to the frame 1, and the volume decrease on the low-pitched sound side can be alleviated. Further, the vibrating plate 5 attached to the pedestal 57 is supported on the high-rigidity side where vibration is weak on the lower end 57b side having high rigidity, so that the high-pitched sound range can be sufficiently transmitted to the frame 1 and the sound volume can be secured.

When the winding shaft 3 is arranged in the center of the frame 1,
The balance of the music box as a whole is improved, and the entire music box is rotated around the winding shaft 3 protruding from the frame 1 or the degree of freedom of attachment to the resonance member is increased.

Further, the drum 4 and the pedestal 57 are attached to the frame 1
Since the vibration valve 5 is installed upright on the side surface 57a of the pedestal 57, the drum 4 and the vibration plate 5 on the frame 1 are mounted.
Of the drum 4 is smaller than that of a general music box in which the rotary shaft of the drum 4 and the vibration valve are provided in parallel with the frame 1, and the music box is small and has good sound quality.

Next, the structure of the speed increasing wheel train 6 and the braking means 7 which constitute the speed adjusting means will be described. The speed increasing train wheel 6 is shown in FIGS.
As shown in FIG. 2, two worms that are orthogonal to each other are adopted, and these worms are arranged as close as possible around the mainspring 2 and a high speed increasing ratio is obtained. Especially, in the 4th worm 17, which is the final stage, the rotation speed is high.

The speed increasing train wheel 6 meshes with the first gear 12 2
No. 3 gear 15, No. 3 worm 15 meshing with No. 2 worm wheel 14 coaxial with this gear 13, No. 3 worm 1
The No. 4 worm 17 meshes with the No. 3 worm wheel 16 arranged coaxially with the No. 5 worm. The rotating body 70 of the braking means 7 is attached to the 14th worm 17. The speed increasing train wheel 6 having such a structure is covered by the gear housing portion 62 to prevent intrusion of dust or foreign matter from the outside.

The No. 3 worm 15 is arranged above the first gear 12 on the case 8 side, and as shown in FIG. 9, when the rotation is transmitted from the No. 2 worm wheel 14, the No. 3 worm 15 is provided. 15 is provided so as to be pressed against the bearing portion 31 formed in the case 8 by the biasing force acting in the thrust direction and the radial direction indicated by arrows C and D. The bearing portion 31 is an inverted U-shaped groove opened downward, and restricts the shaft end 15a of the No. 3 worm 15 from moving upward and sideward.

As shown in FIGS. 9 and 10, a flange 30 is provided at the lower end of the No. 2 worm wheel 14, and the No. 3 worm 15 when rotation is not transmitted is supported by the flange 30. ing.

As shown in FIG. 9, the other end 15b of the No. 3 worm 15 has a bearing portion 32 formed on the inner wall 8A of the case 8 in an inverted U shape with respect to the frame 1 and protruding from the frame 1 side. It is rotatably supported by being sandwiched by a convex portion 33 that fits with. A tongue piece 44 as a position holding member for slightly urging the No. 3 worm 15 toward the bearing portion 31 located in the direction of the biasing force indicated by the arrow C is provided outside the bearing portion 32 supporting the other end 15b. It is molded to 8. This tongue piece 44 is made of resin like the case 8 and is shown in FIG.
As shown in FIG. 2, it is arranged in a space 45 formed by the inner wall 8A and the side wall 8B of the case 8 and protrudes from the case 8 toward the frame 1, and the shaft end 1 of the third worm 15
It is abutting lightly on 5c.

Therefore, even if there is a play between the bearings 31 and 32 and the No. 3 worm 15 that allows for manufacturing and assembly errors, the worm 15 is urged in the direction of arrow C by the tongue piece 44. Therefore, the movement of the worm 15 in the axial direction can be prevented. Further, although the tongue piece 44 is integrally molded with the case 8 here, the tongue piece 44 may be formed as a separate member and attached later, or the tongue piece 44 may be replaced by a leaf spring or the like. good. In any case, it is essential that the position holding member has elasticity.

As described above, since the movement of the third worm 15 in the axial direction can be prevented, the rapid torque transmission to the drum 4, for example, caused by the movement of the mainspring 2 is eliminated, and the rotation of the drum 4 is stable and favorable. A ringing state is possible.
Particularly, since the speed increasing ratio is increased by using the two worms 15 and 17 in the speed increasing wheel train 6, the energy storage force of the mainspring 2 decreases with time and the braking means 7 arranged on the speed increasing side. When the input of the inertial force from is larger, the input rotation causes play in the meshing of gears and makes the rotation of the drum 4 unstable. Therefore, the movement of the third worm 15 in the axial direction is restricted. Doing is extremely important.

Such an important problem is solved by the bearing parts 31, 32.
The problem that can be solved while providing a certain amount of play between the third worm shaft 15 and the third worm shaft 15 enables a smooth assembly of the speed increasing train wheel 6 and further provides a wide range of accuracy with respect to the frame 1 and the case 8. The cost reduction effect can be obtained.

As shown in FIGS. 8 and 9, a No. 3 worm wheel 16 is formed at the intersection of the No. 3 worm 15 and No. 4 worm 17, and a No. 4 worm 1 is formed on the No. 3 worm wheel 16.
7 are arranged and meshed. 4th worm 17
As shown in FIG. 2, one of the shaft ends is inserted into the bearing portion 34 formed in the fixed wall portion 60 of the case 8, and the other end is the No. 3 worm wheel 16 and the reverse portion formed in the case 8. It is supported by the U-shaped bearing portion 35.

Therefore, a member such as a protrusion for supporting the other end of the No. 4 worm 17 from below is not required, and the protrusion from the frame 1 is reduced and the height is low because it is supported at a position close to the frame 1. it can.

The No. 2 gear 13, the No. 2 worm wheel 14, and the flange 30 are integrally molded of plastic or metal as required, and as shown in FIG. 8, project from the case 8 toward the frame 1 side. It is rotatably supported by a shaft 63 that is integral with the shaft 8. Shaft 6
3 is provided so as to project from the ceiling surface of the gear housing portion 62 toward the frame 1 side, and the front end 63a is inserted into the support hole 36 drilled in the frame 1 so that the frame 1 and the case 8 are provided.
And No. 2 gear 13 and No. 2 worm wheel 14 are supported near the frame 1.

The braking means 7 is composed of a rotary body 70 made of an elastic body such as rubber or a rubber-like product, and a fixed wall portion 60 with which the rotary body 70 contacts. The rotating body 70 is formed so as to be displaced in the axial direction by receiving a centrifugal force, and is press-fitted to the shaft end of the fourth worm 17 which is rotated at a high speed. The fixed wall portion 60 is formed with a wall surface (not shown) that slides when the rotating body 70 is displaced, and frictionally brakes by sliding contact with the rotating body 70 that is displaced in the axial direction by a centrifugal force. ing. This frictional braking keeps the rotation of the speed increasing gear train 6 and the drum 4 connected thereto constant.

An opening space 73 for rotatably accommodating the rotating body 70 is formed near the fixed wall portion 60. By inserting a stopper or the like (not shown) from this space 73,
It is also possible to stop the rotating body 70.

[0046]

According to the first aspect of the present invention, the contact portion for preventing the movement of the other end of the mainspring engaged with the engaging portion in the outward direction of the barrel is formed on the frame of the music box. Thus, the movement of the other end of the mainspring can be reliably prevented without adjusting the frictional force relationship between the mainspring and the barrel, and noise due to tapping sound at the other end can be reduced to provide a music box with good sound quality. In addition, since there is no trial and error to derive an appropriate frictional force relationship, the production time can be shortened and the music box cost can be reduced.

According to the second aspect of the present invention, the engaging portion is provided with a restricting member that restricts the movement of the other end of the mainspring inward of the barrel, against the winding force applied to the winding shaft. The movement of the other end of the mainspring toward the inside of the barrel is restricted, the movement of the other end is reduced, and the noise due to the tapping sound at the other end is reduced, resulting in a music box with better sound quality.

According to the third and fourth aspects of the invention, since the pedestal erected on the frame is projected in an L-shape so as to be connected to the frame to form the contact portion, the pedestal is As the mass of the abutting portion increases, the strength of the pedestal with respect to the frame increases. Therefore, the vibration from the diaphragm fixed to the pedestal is efficiently transmitted to the frame, and the music box is excellent in sound quality and volume.

[Brief description of drawings]

FIG. 1 is a perspective view of a music box showing an embodiment of the present invention.

FIG. 2 is a partially cutaway plan view of the music box shown in FIG.

FIG. 3 is an enlarged cross-sectional view showing a drum of the music box shown in FIG. 1 and its supporting structure.

FIG. 4A is a plan view showing an example of a ratchet that connects a winding shaft and a first gear, and FIG. 4B is a longitudinal sectional view thereof.

5 is a front view of the music box shown in FIG. 1. FIG.

FIG. 6 is an enlarged perspective view showing a configuration of a contact portion and an engagement portion, which are essential portions of the present invention.

FIG. 7 is an enlarged cross-sectional view showing an engaged state between the other end of the mainspring and the engaging portion.

FIG. 8 is a side view showing the structure of a speed increasing train wheel.

FIG. 9 is an explanatory diagram showing a relationship between a support structure of a No. 3 worm that constitutes a speed increasing train wheel and a gear that meshes with the support structure.

FIG. 10 is an explanatory diagram showing a relationship between a No. 3 worm, a No. 2 worm wheel, and a flange.

FIG. 11 is an enlarged perspective view showing a support structure for a No. 3 worm.

FIG. 12 is a partial cross-sectional view of a case showing a configuration of position holding means.

[Explanation of symbols]

 1 frame 2 mainspring 2a one end of the mainspring 2b other end of the mainspring 3 winding shaft 4 drum 5 diaphragm 5a vibrating valve 6,7 speed control means 8 case 50 engaging part 51, 52 regulating member 55 abutting part 57 pedestal 61 barrel box A Inside barrel case B Outside barrel box

Claims (4)

[Claims] 1. A vibrating plate having a comb-tooth-shaped vibrating valve, a drum for playing a sound by flipping the vibrating plate, a mainspring as a rotational drive source of the drum, and a barrel for surrounding the mainspring. In a music box supporting on a frame a speed adjusting means for adjusting the rotation speed of a drum, one end of the mainspring is locked to a winding shaft arranged in the barrel, and the other end of the mainspring is placed on the frame. In addition to engaging with the provided engaging portion, the frame is provided with an abutting portion that prevents movement of the other end of the mainspring engaged with the engaging portion in the outward direction of the barrel. Music box to do. 2. The engaging portion has a regulating member for regulating the movement of the other end of the mainspring inward of the barrel, against the winding force applied to the winding shaft. Music box. 3. The music box according to claim 1, wherein the frame has a rotating shaft of the drum arranged vertically and a pedestal to which the diaphragm is attached. 4. The music box according to claim 1, 2 or 3, wherein the abutting portion is formed so as to project from the pedestal in an L-shape and is connected to the pedestal and the frame.