JPH0474346A - Power transmission mechanism - Google Patents

Abstract

PURPOSE:To decrease the number of parts and to improve the assembly workability by constituting the mechanism so that a rotary plate fixed coaxially to a worm gear is engaged and detached directly to and from the outside periphery of a fly-wheel of a capstan by turining of a holder, and power transmission is switched. CONSTITUTION:A holder 39 for supporting a shaft 41 to which a rotary plate 42 and a worm gear 43 are fixed is supported so as to be turnable by a synchro nizing shaft 37 of a cassette loading mechanism, and a transmission gear 40 is provided on t;he synchronizing shaft 37 and the holder 39. By clockwise turning of the holder 39, a transmission gear 43 and a gear 44 are engaged, and form the gear 44, rotary driving force is transmitted to the synchronizing shaft 37 through the worm gear 42, the transmission gear 40, and a transmission gear 38. In such a way, the power transmission mechanism in which the transmis sion efficiency is satisfacetory, the number of part is small, and the assembly workability is satisfactory is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording/reproducing apparatus and to switching of power transmission to a cassette loading mechanism during tape loading.

[Prior Art] Figures 6 to 8 are diagrams showing a conventional magnetic recording/reproducing device disclosed in, for example, Japanese Patent Laid-Open No. 63-94456, and Figures 6 and 7 mainly show the rear surface of the chassis. FIG. 8 is a side view showing the cassette loading mechanism.

In Figure 1, (1) is the chassis, (3) is the chassis (
(1) is a capstan rotatably supported; (4) is a flywheel fixed to the capstan (3); (10) is a flywheel fixed to the capstan (3);
0) is a main cam rotatably supported on the back side of the steering wheel (1), (101) is a cam groove formed on the back side of the main cam (100), and (102) is engaged with the cam l (101). The pin (103) is a slide plate on which the pin (102) is installed and rotatably supported under the shaft (]), (104) is installed on the chassis (1) and is the center of rotation of the main cam. pin, (105) is chassis (1)
The pins (106) and (107) implanted in the slide plate (103) are formed on the slide plate (103), and the pins (104) and (10
5) is inserted into the guide groove, (108) is the slide plate (1
The pressing part (109) is formed on the chassis (1).
); (110) is a torsion spring engaged with lever (109); (111) is an idler rotatably supported by lever (109);
112) is a cassette loading mechanism attached to the chassis (1); (113) is a shaft rotatably supported by the cassette loading mechanism; (114) is a shaft rotatably supported by the cassette loading mechanism;
) is a worm gear fixed to the shaft (113), (
115) is a pulley fixed to the shaft (113), (
116) is an idler and a belt suspended from the booby.

Next, the operation will be explained.

FIG. 6 shows a state in which the tape pull-out member is loaded and the magnetic tape is attached to the magnetic head. When unloading is started from this state, the loading motor rotates and the power is transferred to the transmission gear (20). The main cam (100) is driven to rotate clockwise. Then, due to the engagement between the pin (102) and the cam groove (101), the slide plate (103) slides to the left, applying pressure to the torsion spring (110), and the lever (109) moves backward as shown in FIG. The belt (116) is rotated clockwise and attached to the outer periphery of the flywheel (4). If a rotational force is applied to the capstan (3) in this state, this rotational force will be
The driving force is transmitted from the belt (116) via the pulley (115) to the worm gear (114), which transmits the driving force to the cassette loading mechanism.

[Problems to be Solved by the Invention] Conventional magnetic recording and reproducing devices are configured as described above, and because idlers and belts are used to transmit power to the cassette loading mechanism, there is no loss in power transmission. There were problems such as a large size, an increase in the number of parts, and poor workability since the cassette loading mechanism unit and shearn could not be disassembled without first removing the belt.

This invention has been made to solve the above-mentioned problems, and aims to provide a power transmission mechanism that has good transmission efficiency, a small number of parts, and is easy to assemble.

Means for Solving the Problems j In order to solve the above object, the power transmission mechanism according to the present invention is such that a holder supporting a shaft to which a rotating plate and a worm gear are fixed can be rotated around a synchronized shaft of a cassette loading mechanism. It is equipped with a synchronous shaft and a transmission gear on the holder.

[Function] In the power transmission mechanism according to the present invention, as the holder rotates, a rotary plate coaxially fixed to the worm gear directly engages and disengages the outer periphery of the flywheel of the capstan, thereby switching power transmission.

[Embodiment 1] An embodiment of the present invention will be described below with reference to FIGS. 1 to 5. Fig. 1 is a plan view of the main part showing the unloading state, Fig. 2 is a plan view of the main part in the magnetic tape playback state, and Figs. 3 and 4 are cross sections of Fig. 1 showing the switching operation of power transmission. FIG. 5 is a vertical cross-sectional view taken from section II-I, and FIG. 5 is a vertical cross-sectional view taken from cross section ■-■ in FIG. do.

In the figure, (1) is the chassis, (2) is the chassis (1
), (3) is a capstan supported by the chassis (1), (4) is a flywheel fixed to the capstan (3), and (5) is attached to the chassis (1). Cylinder base, (6) is cylinder base (5
), (7L(8) is a guide groove formed in the chassis (1), (9) and (10) are tape drawers each inserted into the guide groove (7L(8)) Element,
(11) is a regulation pin provided on the chassis (1), (1
2) is an arm that has a regulation pin (11) implanted therein and is rotatably supported on the chassis (1), and (13a) is an arm that is rotatably supported on the chassis (1).
1) is attached to a metal printed circuit wiring board (hereinafter abbreviated as metal board), (13b) is a capstan coil glued to the metal board (13a), (14L (15) is fixed to the chassis (1) Tabutshu, (16L (17)
are the clampers attached to the chassis (1), (1
8) is a locking part formed on the clamper (15), (19)
is a holder (
20) is the transmission gear supported by the holder (19), (
21) is a first rotary plate rotatably mounted on the outer periphery of the bushing (14) and held between the clamper (14) and the chassis (1), and (22) is a first rotary plate rotatable on the outer periphery of the bushing (15). The clamper (15) and the chassis (
1), the second rotating plate (23) is the second rotating plate (22), the tape drawing member (9) and the arm (12).
), the connecting member (24) is the second rotary plate (
22) and the tape pull-out member (10), (25) is a pin implanted in a part of the second rotating plate (22), and (26) is a connecting member connecting the first rotating plate (21). ), (27) is a gear part formed on the outer periphery of the second rotating plate (22), and (28) is the first rotating plate (21).
The intermittent part (29) formed on the outer periphery of the gear part (26)
The leading tooth provided at the tip of (30) is the gear part (27)
The contact part (31) provided at the tip of the lever (32) is pivotably supported on the chassis (1).
), (33) is a slide plate slidably provided on the chassis (1), (34) is a sliding contact part formed on the slide plate (33), (35) is a slide Board (
33), and (36) is the chassis (1).
The cassette housing (37) attached to the cassette housing (36) is a synchronous shaft whose both ends are rotatably supported, (38) is a transmission gear fixed to the synchronous shaft (37), and (39) is a synchronous shaft. (40) is a transmission gear rotatably supported on the holder (39); (41) is a shaft rotatably supported on the holder (39); (42) is a transmission gear rotatably supported on the holder (39); ) is the shaft (41
), the worm gear (43) is fixed to the shaft (4
2) is a rotary plate fixed to, (44) is a flywheel (
The gear (45) is formed on the outer periphery of the chassis (1).
) is attached to the capstan holder (3) and supports the capstan (3). The capstan holder (46) is a pressing part formed on the holder (39), and
9) is a tension spring engaged with the negative part of the cassette housing (36), (48) is a contact portion formed on the lever (31), and (49) is formed on the outer periphery of the rotating plate (43). It's a gear.

Next, the operation will be explained.

FIG. 1 is a diagram showing a state in a first position where the tape drawing members (9), (10) and the regulating pin (11) can be drawn out from the tape cassette, that is, a state before loading. Second
The figure shows the second position in which the magnetic tape is pulled out of the tape cassette and attached to the magnetic head (6), that is, the state in which loading is completed.

When loading is started in Fig. 1, the loading motor rotates, and this rotational driving force is transmitted through the deceleration mechanism.
It is transmitted to the first rotary plate (21) via the transmission gear (20), and the first rotary plate (21) rotates counterclockwise. The second rotary plate (21) is engaged with the first rotary plate (21).
22) receives rotational driving force from the first rotary plate (21) and rotates clockwise. Then, the connecting member (23), (
24) rotate together with the second rotary plate (22) and move the tape pull-out members (9) and (10), respectively, to the position shown in FIG. In the middle of this, the pin (25) is attached to the sliding contact part (32).
) and rotate the lever (31) counterclockwise. Then, due to the sliding contact between the abutting part (48) and the sliding contact part (34), the slide plate (33) slides upward, and the abutting part (35) pushes the abutting part against the tension spring as shown in FIG. (47)
It rotates counterclockwise against the urging force of. In this state,
Even if rotational force is applied to the capstan, no power is transmitted to the cassette loading mechanism because the gear (44) and the transmission gear (43) are not engaged.

At this time, the reaction force of the pressing of the tape pull-out member (9L (10)) goes around slightly to the right of the center of rotation of the second rotary plate (22), so that the engaging part (18) and the pin (25) come into contact with each other. Even if pressure is generated on the second rotary plate (22) and the engagement with the first rotary plate (21) is released, even if an external force such as vibration is applied to the second rotary plate (22), the second rotary plate (22) ) maintains the pressure on the tape pull-out members (9) and (10) without rotating counterclockwise.

In this state, a mode detection mechanism (not shown) detects
Enters the mode for playing or recording magnetic tape.

Next, when taking out the tape cassette (4) from the apparatus, when the eject button is pressed, the loading motor rotates and the first rotary plate (21) rotates clockwise. Then, the leading tooth (29) pushes down the abutting part (30),
The gear part (26) and the gear part (27) are engaged, and the second rotating plate (22) receives power from the first rotating plate (21) and rotates counterclockwise, and the connecting member (23) ), (24) move downward, the pressure of the tape pull-out members (9), (10) against the cylinder base (5) is released, and the tape pull-out members (9L (10) ) to the position shown in FIG.

During this process, the pin (25) separates from the sliding contact portion (32), so the lever (31) is rotated clockwise by the biasing force of the tension spring (47). Also, at the same time, the holder (39)
rotates clockwise as shown in Figure 3, so the transmission gear (4
3) and the gear (44) are engaged. If rotational force is applied to the capstan in this state, the gear (44) will move from the rotating plate (43).
), the worm gear (42), the transmission gear (40), and the transmission gear (38), the rotational driving force is transmitted to the synchronous shaft (37), and the cassette loading mechanism operates.

In addition, although the above embodiment shows an example in which gears are formed on the outer periphery of the rotating plate (43) and the flywheel (4), power transmission may be performed by attaching a high-friction member such as a comb. . .

[Effects of the Invention] As described above, according to the present invention, a holder supporting a shaft to which a rotating plate and a worm gear are fixed is rotatably supported on a synchronizing shaft of a cassette loading mechanism, and a transmission gear is connected to the synchronizing shaft and the holder. Since this is provided, it is possible to obtain a power transmission mechanism that has high transmission efficiency, has a small number of parts, and is easy to assemble.

[Brief explanation of the drawing]

1 and 2 are plan views showing one embodiment of the present invention, FIGS. 3 and 4 are longitudinal cross-sectional views of main parts as seen from section II in FIG. 1, and FIG. A vertical cross-sectional view of the main part as seen from the cross section (■-■) in the figure, FIGS. 6 and 7 are a plan view showing a conventional example, and FIG. 8 is a side view thereof. In the figure, (1) is the chassis, (3) is the capstan, (4) is the flywheel, (9L (10) is the tape pull-out member, (37) is the synchronization shaft, (38) is the transmission gear, (3) is the
9) is a holder, (40) is a transmission gear, (4]) is a shaft (42) is a worm gear, (43) is a rotating plate, (1)
12) is the cassette loading mechanism. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] The power transmission mechanism has a cassette loading mechanism that attaches the tape cassette to the chassis, and uses a capstan to switch between transporting the magnetic tape and driving the loading of the tape cassette.The cassette loading mechanism uses a holder that supports a shaft to which a rotating plate and a worm gear are fixed. rotatably supported on a synchronization shaft that transmits power of the mechanism, a transmission gear is provided on the synchronization shaft, and a transmission gear that engages with the transmission gear and the worm gear is provided on the holder;
A magnetic recording and reproducing device characterized in that the flywheel of the capstan and the rotary plate are engaged and disengaged by rotation of the holder, and the rotational driving force of the flywheel is transmitted to the synchronizing shaft of the cassette loading mechanism. Power transmission mechanism.