JPS58141460A - Torque transmitting mechanism for tape recorder - Google Patents

Abstract

PURPOSE:To simplify the mechanism without damaging essential functions and make the mass production possible, by using a centrifugal clutch mechanism as a distributing mechanism, which transmits the rotation torque to either of two reel bases, to change automatically the transmission torque for reproduction and rapid traverse. CONSTITUTION:The centrifugal clutch mechanism is provided in a flyweel 3; and when a motor 1 is rotated in a high speed at the rapid traversing time or the rewinding time, a centrifugal clutch is operated automatically to connect the fly-wheel 3 and a slip wheel 4 directly, thereby winding up a tape in a high speed stably. Said centrifugal clutch has a tooth part 14a on the outside circumference and is stored in the fly-wheel 3 movably in the direction of the diameter, and a movable piece 14 cannot be moved in the outward direction at the reproducting (low-speed rotation) time because the elastic force of a spring 15 is stronger than the centrifugal force generated in the movable piece 14; and at the rapid traversing (high-speed rottion) time, the movable piece 14 is projected in the outward direction because the centrifugal force of the movable piece 14 is stronger than the elastic force of the spring 15, and the tooth part 14a and a tooth part 4b of the slip wheel 4 bite each other, and the rottion torque of the fly-wheel 3 is transmitted to the slip wheel 4 without slip; and thus, the torque of a motor 1 is transmitted surely to reel bases.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultra-small cassette tape recorder, and technically it can be applied to tape recorders including center capstan type open reel types.

The micro cassette tape recorder has realized a blurred size by making the mechanism ultra-miniaturized and highly precise.The present invention also aims to simplify the mechanism, mass production, and reduce costs without sacrificing the original function. This is what we aim to provide.

The torque transmission mechanism of conventional micro cassette tape recorders supplies rotational torque of 140 1J- from the motor.
In order to supply the reel stand and take-up type reel stand, the pressing force from the button was separately transmitted to the reel stand on either side of the kine. However, in the conventional embodiment shown in Figure 1, if all the idlers 7 are distributed to the reel stand side to be connected, the idlers 7 will rotate in the direction of escape, so the idlers 7 must be supported. It is necessary to firmly lock the idler arm 5 against the reaction force, and in a micro cassette tape recorder with a small internal volume and high density, there is room for an electromagnetic plunger to lock the idler arm 5. Not.

It was difficult to control electrically. Therefore, it was impossible to operate the mechanism by electrically programming it like in a cassette-type tape recorder.

In addition, in the conventional example, the reel stands 8a and 8b are provided with fuel l.
A friction mechanism using f is installed to suppress the occurrence of wow and fluff caused by uneven tape running after the reel stand. Load fluctuations caused by meshing, eccentricity of the rotating body, etc. directly affect the rotation of the capstan, causing wow and flutter. The present invention was devised to solve the above-mentioned drawbacks, and will be explained below with reference to the drawings.

FIG. 2 is a plan view of the torque transmission mechanism according to the present invention, and shows the current wheel train combination in a play state.

Currently, capstan 2 and pinch roller 12
The opening sound, as the magnetic tape 13 was being held and being fed,
Binion 4a on slip wheel 4 attached coaxially with capstan 2, and idler 7a made of gears
and 7b are engaged with each other.

In order for the idlers 7a and 7b to always mesh with the binion 4a, the idlers 7a and 1b are pivoted on idler shafts 6a and 6b, which are coaxially mounted on the capstan 2 and fixed at the ends of the rotatable idler arm 5. It is what you are wearing. In this figure, Capsta/
Since the idler arm 5 and the pinion 4a are rotated to the right position, the idler arm 5 is also rotated to the right position, and as a result, the idler arm 5 is rotated to the right side.
a meshes with the teeth on the take-up reel stand 8a, and rotational torque is transmitted.

It is idling because no load is connected. The father supply side reel stand 8b is separated from the idler 1Fb, but due to the tension of the tape 13 pulled by the capstan 2 and the pinch roller 12, the rake of the back tension brake mechanism (not shown) is released. Even though it is rotating, it is rotating to the right M.

Note that the rotational torque distributed by the idler arm 5 and the idlers 1a and 7b can be distributed by changing the rotating direction of the mechanism 1 and the binion 4a with a switch, so in a micro cassette tape recorder with a small internal volume, Because it can be controlled electrically without using electromagnetic plungers, etc.

It is highly desirable in terms of space, cost, and reliability.

FIG. 3 shows the A-A@ section of FIG. 2.

The shaft of the motor 1 disposed on the board forms a capster/2 and functions as a DD momo. A flywheel 3 is fitted onto the capstan 2 and rotates together with the capstan 2, and a felt 9, which is a crimp bat, is attached to the axial end surface of the flywheel 3. A lid-shaped slip wheel 4 is pivotally attached to the capstan 2 so as to be movable in the axial direction so as to press the felt 9, and is pressed downward by the elastic force of the compression spring 11. That is, due to this pressing force, friction is generated between the axial end face of the slip wheel 4 and the felt 9 fixed to the flywheel 3 soil, and rotational torque is transmitted from the flywheel 3 to the slip wheel 4 by this friction. It is.

It has become conventional. Compared to a method in which a sliding mechanism using a felt hook is installed in the reel stand, this method has a sliding mechanism immediately after the motor 1, so there is no overload, reaction force, or shooting that occurs from the subsequent transmission path. etc. can be cut here, thereby ensuring the advantages of the DD momo one-way system.

In other words, the benefits of DD momo are load driving 11!7
By integrating the In (capstan) and the motor shaft, it is possible to control the rotation speed without interruption and accurately, and in this mechanism, even if the load of the reel stand is overloaded, the sliding mechanism remains unchanged. Because the overload sound is not transmitted to the motor,
The rotation of the capstan is maintained accurately at all times.

The torque transmission mechanism from the slip wheel 4 to the reel stand 8 is as explained in FIG. Side reel stand 8a
The idler 7a is pivotally connected to the idler shaft 6a of the idler arm 5, and the idler arm 5 is pivotally connected to the capstan so that its axial movement is restricted. .

Furthermore, during fast forwarding and rewinding, approximately twice as many rotations as during playback are required. For this reason, a centrifugal cuff launch mechanism is provided in the flywheel 3 as shown in Fig. 4, and the motor 1. When the tape is rotated at full speed, the centrifugal clutch is automatically activated to directly connect the flywheel 3 and the four slip wheels, thereby stably winding the tape at high speed.

The structure of this centrifugal cuff lunch includes a bellows 14a on the outer periphery.
A movable piece 1 that is housed in a radially movable 0145 inside the flywheel 3 and rotates together with the flywheel 3.
4, and a spring 1 that pulls the movable piece 14 toward the center of the meeting.
5, and a tooth portion 4 formed on the inner peripheral end surface of the slip wheel 4.
During playback (low-speed rotation), the resiliency of the spring 15 is stronger than the centrifugal force generated in the movable piece 14, so the movable piece 14 cannot move outward, resulting in fast forwarding (high-speed rotation). ) At times, the centrifugal force of the movable piece 14 overcomes the resiliency of the spring 15, and the teeth 1 protrude outward.
4a and the toothed portion 4b of the slip wheel 4 mesh with each other, and the rotational torque of the flywheel 3 is transmitted to the slip wheel 4 without slipping, thereby reliably transmitting it to the torque reel stand of the motor 1.

Another embodiment of the sliding mechanism in the torque transmission mechanism is shown in FIG. 5 and will be described.

Felt 9, which is a crimp bat in Figure 3
The slip wheel 4 was pressed in the axial direction by the compression spring 11, but in Fig. 5, nine felts are arranged in the radial direction perpendicular to the axis, and a spring exerting force in the same direction is used. A felt F9, which is a pressure bonding bat, is brought into contact with the smooth inner surface of the slip wheel 4, which is shaped to cover the flywheel 3 by pressing.

A part of the CC cross section in this figure is shown in FIGS. 6 and 7.

In the method shown in FIG. 6, a crimp butt mounting member 10 having a felt 9 stuck to a recess in the flywheel 3 is arranged so as to move in the radial direction of the flywheel 3.

It is elastically repelled in the radial direction by the compression spring 11,
By bringing the outer periphery of the felt 9 into contact with the smooth surface of the inner periphery of the slip wheel 4, the entire rotational torque from the flywheel 3 is transmitted to the slip wheel 4 by the friction, and it slips when overloaded. It is.

The method shown in FIG.
It is arranged along the circumference near the outer periphery of the flywheel 3, and is arranged in opposite directions so that the same transmission torque can be obtained for both forward and reverse rotations. The effect is the same as that shown in FIG.

It goes without saying that in the configuration shown in FIG. 5, in addition to the sliding mechanism shown in FIG. 6 or 7, only the centrifugal clutch mechanism shown in FIG. 4 can be mounted in the flywheel 3. There is no such thing.

Although not clearly shown in the drawings, joints are provided between the center of the rotating part of the idler arm 5 and the center of the idler arm 6, so that they can be bent freely. By tensioning the spring, the idlers 7a and 7b can engage the vinyl off 4a with a constant contact pressure. Furthermore, in this explanation, all gears in the transmission system from the slip wheel 4 to the reel stand 8 are used for convenience, but it is clear that a friction transmission system using a rubber friction wheel can also be used.

As explained above, according to the rotary torque transmission mechanism of the present invention, the mechanism does not require any power source other than the motor to distribute the rotary torque to one of the two reel stands. , and the mechanism can be simplified, and by using a centrifugal clutch mechanism, the transmission torque during regeneration and fast forwarding can be automatically changed by changing the rotational speed of the motor, which also drives the clutch mechanism. No other power source is required for the operation, and especially in micro-force cent tape recorders, the internal space can be used meaningfully and costs can be reduced, which is a remarkable effect.

[Brief explanation of the drawing]

Fig. 1 is a diagram of a conventional embodiment in which the distribution is mechanically operated by an external force, Fig. 2 is a plan view of an embodiment according to the present invention in which the distribution is automatically operated by a mechanism, and Figs. 3 and 5. 5 is a partial cross-sectional view of an embodiment of the present invention, and FIG. 4 is a cross-sectional view of a centrifugal clutch mechanism according to the present invention. 6 and 7 each show a partial sectional view of a sliding mechanism according to the invention. 1...Motor, 2...Capstan, 3
... Flywheel, 4... Slip wheel, 4a binion, 4b... Slip wheel teeth, 5... Idler arm, 6a, 6b... Idler shaft, 7a... Winding side idler , 7b... supply side idler, 8a...
Take-up side reel stand, 8b/supply 11101J-
Le stand, 9... Crimping bat (felt), 10
. . . Crimp butt mounting member, 11 . . Crimp spring, 12 . . Pinch roller 113 . ·spring. Patent Applicant No. t Figure 42 Ward --- 473 Figure 4 Figure 1

Claims (6)

[Claims] (1) In a center cab stan type tape recorder, there is a flywheel that rotates integrally with the capstan, a t'(t') disposed coaxially with the capstan, and a sliding mechanism and a clutch a structure connected to the flywheel. A slip wheel to be driven, an idler arm rotatably disposed coaxially with the capstan, and an idler arm rotatably disposed at a predetermined angle apart from the tip of the idler arm, which is driven by the slip wheel. a take-up side idler and a supply side idler, a take-up side reel stand driven by the take-up side idler, a supply side reel stand driven by the supply side idler,
When each of the above-mentioned idlers contacts and drives each reel stand, each idler is arranged so that the center point of each idler is outside the line connecting the center of the capstan and the center of each reel stand. The torque of a tape recorder is characterized in that the target reel stand is turned on during driving by changing the direction of rotation of the capstan, and the transmission torque is changed by changing the number of rotations of the capstan. transmission mechanism. (2) In the scope of the first claim, a joint portion is provided between the center of rotation of the idler arm and the center of rotation of each idler, so that the arm can be bent freely. A torque transmission mechanism for a tape recorder. (3) A torque transmission mechanism for a tape recorder according to claim 1, characterized in that the capstan and the shaft of the motor are integrally constructed. (4) In the scope of the first claim, the slip wheel is disposed so as to be movable in the axial direction, and a crimp butt is provided between the axial end surfaces of the front flywheel and the slip slip wheel; A pressure layer spring that is resilient in the axial direction is arranged between a part of the capstan and the slip wheel, and the elastic force of the layer spring presses the crimping butt, so that the pressure layer spring is pressed between the flywheel and the slip wheel. A torque transmission mechanism for a tape recorder, characterized in that the sliding mechanism is configured to transmit rotational torque by generating friction chips. (5) In the scope of the first claim, it is provided that either the flywheel or the slipwheel is disposed so as to cover the outer periphery of the other, and the pressure layer butt is attached by crimping and affixing the discs. The member is disposed in a space inside the flywheel so as to be movable in the radial direction, and the attached pressure layer spring causes the crimping ball to be elastically repelled in the radial direction, and is pressed against either the outer periphery or the inner periphery of the crimping butt slip wheel. The sliding mechanism is characterized in that the sliding mechanism is configured to transmit one rotation torque by generating frictional force between the flywheel and the slip wheel. Torque transmission structure for tape recorder 1. (6) Within the scope of the claims set forth in paragraph 1. A torque transmission mechanism for a tape recorder, wherein the clutch mechanism is a centrifugal force clutch mechanism that performs multiple operations due to centrifugal force. (Within the scope of the claims set forth in Items 1 and ♀. A movable member having teeth on the outer periphery, movable in the radial direction, and rotating integrally with the flywheel 3. a slip wheel disposed together with a spring that pulls the movable piece toward the center, and a slip wheel disposed to cover the outer periphery of the flywheel;