JP2538279B2 - Mode switching device - Google Patents

Description

The present invention relates to a mode switching device in a magnetic recording / reproducing device.

(Prior Art) As a conventional mode switching device of this type, there is a device for transmitting power to three systems next using a positive cam (9) as shown in FIG.

In the first transmission system, a geneva gear (92) is meshed with a gear portion (91) formed on the outer periphery of the cam (9) to form an intermediate gear (93).
Through a pair of arc-shaped loading rings (21) (22)
Is driven to rotate, and the tape is guided from the cassette (not shown) by the tape leading guides (23) and (24) on the loading rings (21) and (22) and wound around the head cylinder (11).

The second transmission system is a drive lever (95) for driving the pinch roller lever (6) in the cam groove (94) outside the cam (9).
Of the pin (96) is slidably fitted, and the rotation of the cam (9) causes the pinch roller lever (6) to rotate via the drive lever (95), and the pinch roller (61) to the capstan (14). Press.

In the third transmission system, the pin (99) of the mode switching slider (98) is slidably fitted in the cam groove (97) inside the cam,
When the cam rotates, the slider (98) moves linearly,
By the movement of the slider, the reel breaker release lever (8) in the cassette, the back tension lever (90), etc. are driven.

The release lever (8) has a release pin (82) projecting upward at its free end, and as shown in FIG.
The release pin (82) penetrates into the receiving hole (104) of the brake body (103) provided between the two reels (101) and (102), and the release lever (8) is rotated clockwise. Release the brake of the reel by retracting the brake body (103) against the spring (105) and separating the brake claw (106) protruding from the brake body from the tooth surface (107) formed on the outer peripheral surface of the reel. To do.

(Problems to be solved) In the above mode switching device, the stroke of the drive lever (95) and the stroke of the slider (98) are changed to the cam groove (94).
The cam groove (94) (97) must be doubled inside and outside by securing the curvature change of (97), and the diameter of the cam (9) becomes large, which hinders downsizing of the mechanism. there were.
Further, the friction resistance between the cam grooves (94) (97) and the pins (96) (99) causes power transmission loss, and it is necessary to increase the capacity of the motor.

(Means for Solving Problems) According to the present invention, a protrusion is provided on a rotating body rotated by a motor, and the tape loading device and the mode switching lever are driven by the rotation of the protrusion, thereby reducing the size of the mechanism. The purpose of the present invention is to clarify a mode switching device that can realize a reduction in power transmission loss while achieving realization.

In the mode switching device of the present invention, a shaft-shaped protrusion (31) is provided at an eccentric position of a rotating body (3) linked to a motor (12), and the loading lever (4) is engageable with the protrusion (31). ) And a mode switching lever (5), a tape loading device (2) is connected to the loading lever (4), and a pinch roller lever (5) is provided between the mode switching lever (5) and the capstan (14). ) Is provided, and the pinch roller lever (6) is pressed against the capstan (14) by the movement of the mode switching lever.

(Operation and Effect) The rotation of the rotating body (3) also rotates the protrusion (31), which causes the loading lever (4) and the mode switching lever (5) to rotate.

By the rotation of the loading lever (4), the tape loading device (2) is driven to perform the tape loading, and by the rotation of the mode switching lever (5),
The pinch roller lever (6) is pressed by the capstan (14).

The rotator (3) only needs to be provided with the protrusion (31) at an eccentric position, and the diameter of the rotator (3) is smaller than that of the conventional positive cam having a plurality of cam grooves. Yes, the mechanism can be made compact. Further, compared with the friction resistance between the conventional positive cam and the pin, the friction between the protruding shaft and the levers (4) and (5) is small, and the power transmission loss can be reduced.

(Embodiment) In the embodiment, when the standby mode when the tape cassette (100) shown in FIG. 5 is inserted into the play mode when recording / reproducing shown in FIG. 6, the depth dimension of the mechanism is shortened. It is a mode switching device in the VTR.

The VTR is a reel chassis (7) that can approach and separate from the head cylinder (11) on a main chassis (1) provided with a head cylinder (11) and a mode switching device (2).
Have been deployed.

As shown in FIG. 1, a tape loading device (2) is provided on the main chassis (1) so as to surround the head cylinder (11), and the tape loading device (2) extends along the head cylinder (11). It is composed of a pair of loading rings (21) (22) rotatably arranged and tape leading guides (23) (24) connected to the respective loading rings (21) (22).

The loading rings (21) (22) have different running heights, and each has a tooth surface (20) formed on the outer circumference.

A rotating body (3) is arranged on the left rear side of the head cylinder (11), and a worm gear (12) rotated by a loading motor (12) with respect to a tooth surface (30) of a helical tooth formed on the outer periphery of the rotating body (3). 13) is in mesh.

The rotating body (3) is the main chassis (1) as shown in FIG.
It is suspended and supported by a support base (16) fixed to the shaft, and a shaft-like protrusion (31) is provided so as to project downward at an eccentric position of the rotating body (3).

A loading lever (4) and a mode switching lever (5) which are rotated by the rotation of the rotating body (3) are rotatably provided between the rotating body (3) and the main chassis (1).

As will be described later, as the rotating body (3) rotates counterclockwise, both levers (4) and (5) are driven, and from the standby mode of FIG. 1 to the stop mode of FIG. 2 and the play of FIG. The mode shifts to the rewind / rewind reproduction mode shown in FIG.

As shown in FIG. 2, a capstan (14) is provided on the right side of the head cylinder (11), and a pinch roller lever (6) is pressed against the capstan (14) behind the capstan (14). A pressing lever (65) is provided, and the pressing lever (65) and the mode switching lever (5) are connected to each other by the connecting plate (5
It is pivotally connected in 7).

As shown in FIG. 1, the loading lever (4) is pivotally supported by the support shaft (40) at its substantially central portion, and the sector gear (41) is provided at one free end and the cam groove (43) is provided at the other free end. ing.

The sector gear (41) is connected to the loading rings (21) (22) via a gear train (15). Although only one gear train (15) is shown in the drawing, there are actually two series, and the final gears of each gear train rotate in mutually opposite directions, one final gear on the upper loading ring (21) and the other. Is engaged with the lower loading ring (22), and the counterclockwise rotation of the sector gear (41) causes both loading rings (21) and (22) to rotate in opposite directions to each other, and the tape leading guide ( The tape is wound around the head cylinder (11) by running the tapes (23) and (24) in the loading direction.

The protrusion (31) of the rotating body (3) is slidably fitted in the cam groove (43) of the loading lever (4), and the inner side of the cam groove (43) has an arc-shaped relief (44). ).

When the rotating body (3) rotates counterclockwise and shifts from the standby mode shown in FIG. 1 to the stop mode shown in FIG. 2, the protrusion (31) of the rotating body (3) moves toward the loading lever (4). While sliding in the cam groove (43), the lever is pressed to rotate counterclockwise, and when the stop mode is reached, the protrusion (31) enters the escape portion (44).

In the state of the stop mode, the radial center of the escape portion (44) coincides with the rotation center of the rotating body (3), and thus the rotating body (3)
Even if is further rotated counterclockwise, the loading lever (4) remains stationary in the stop mode, and the tape leading guides (23) and (24) remain stopped at the loading completion position.

As shown in FIG. 1, the central portion of the mode switching lever (5) is pivotally supported by the support shaft (50) standing upright at the rear of the rotating body (3).
The lever is biased in the counterclockwise direction by the spring (53) and rests against the stopper (54).

On the head cylinder (11) side of the mode switching lever (5), two first and second notches (51) (52) are opened,
In the standby state of FIG. 1, the protrusion (31) of the previous rotating body (3) is located in the first cutout portion (51) on the free end side.

When the rotating body (3) rotates counterclockwise, the protrusion (31)
Escapes from the first cutout portion (51) and hits the mode switching lever (5) immediately before the stop mode in FIG. 2 to rotate the lever slightly clockwise against the spring (53).

Further, when the rotating body (3) rotates counterclockwise, the protrusion (31) of the rotating body (3) fits into the second cutout portion (52) of the mode switching lever (5) and slides the lever. Is rotated clockwise to shift to the play mode shown in FIG.

During the transition to the play mode, the reel brake release lever (8) in the cassette described below is operated by the movement of the loading lever (4) to release the reel brake.

As shown in FIG. 1, the connecting plate (57) connecting the mode switching lever (5) and the pressing lever (65) has elongated holes (56) (56).
The guide shaft (17) protruding from the main chassis (1) is fitted in the elongated hole (56), and the connecting plate (57) is opened.
Can slide left and right.

The central portion of the pressing lever (65) is pivotally supported by the support shaft (68), and the notch (69) formed at the free end on the connecting plate side is fitted with the shaft (58) protruding from the connecting plate (57). A cam surface (601) for pressing the pinch roller lever (6) in the stop mode position to the capstan (14) side is formed at the free end on the capstan (14) side.

The pinch roller lever (6) is pivotally supported by a support shaft (60) provided so as to project from the main chassis (1) and has a pinch roller (61) at its tip. Further, a protruding shaft (602) which is fitted in a cam hole (75) of a reel chassis (7) described later with a margin in a substantially central portion of the pinch roller lever (6) is projected upward.

A crimping lever (62) is pivotally supported on the support shaft (60) below the pinch roller lever (6), and the lever (62) and the pinch roller lever (6) are connected by a spring (64). .

The pressure lever (65) has a cam surface (60
A roller (63) capable of contacting 1) is pivotally supported.

Also, the pressing lever (65) and a take-up reel stand (72) described later.
A reel base brake lever (33) is provided between the lever base and the lever base. The lever is biased counterclockwise by a spring (36) about a fulcrum (37), and a hit shaft (projected on the lever (33) ( 35) rests against the pressing surface (38) of the pressing lever (61). When shifting from the stop mode to the play mode, the pressing lever (65) rotates a little clockwise to release the pressing force on the reel base brake lever (33), and the reel base brake (33) becomes the brake shoe (34). To the take-up reel stand (72).

A long hole (55) is formed at the free end of the mode switching lever (5) on the side of the connecting plate (57), and the long hole (55) is long in the left and right and has a downward expansion portion (56) in the center. are doing.

A brake drive lever (86) is pivotally supported on the main chassis (1) above the free end of the mode switching lever (5).

As shown in Fig. 8, the brake drive lever (86) has a horizontal rod (87).
Longitudinal rod (88) projecting toward the rotating body (3) at approximately the center of
The horizontal rod (87) is pivotally supported by the support shaft (89) on the main chassis (1), and the shaft (85) protruding downward at the left end is formed by the mode switching lever ( It is slidably fitted in the long hole (55) of 5).

At the intersection of the horizontal rod (87) and the vertical rod (88) of the brake drive lever (86), an inclined surface (80 continuous with the right side surface of the vertical rod is provided.
1) has been formed.

As shown in FIG. 5, a supply reel stand (71) and a take-up reel stand (72) are provided on the reel chassis (7), and a reel brake release lever (8) in the cassette is provided behind the supply reel stand (71). Is arranged so that it can swing.

The release lever (8) has a long arm (81) extending from the center of rotation (80) to the right and a short arm (83) extending to the left of the take-up reel bases (71) (72). (8
A brake release pin (82) is projected upward at the tip of 1).

A shaft body (84) is provided so as to project downward at the tip of the short arm (83), and the shaft body (84) penetrates the window hole (73) opened in the reel chassis (7), and the standby state shown in FIG. In the mode, the shaft body (84) is in contact with the slope (801) of the brake drive lever (86).

When the cassette is loaded into the reel chassis (7), the 9th
As shown in the figure, the brake body (10
The pin of the release lever (8) fits into the receiving hole (104) of 3).

When the lever rotates clockwise, the brake body (103) withdraws from the reel against the spring (105), and the brake pawl (106) forms a tooth surface ( 107) and release the brake on the reel.

As shown in FIG. 5, a slot (74) is formed in front of the supply reel base (71) in the reel chassis (7), and a drive shaft (42) projecting from the loading lever (4) is provided in the slot. It is slidably fitted.

The groove hole (74) is composed of a horizontally long straight groove hole (74a) and a clearance groove hole (74b) that extends obliquely upward from the left end of the groove and is curved in conformity with the rotation locus of the drive shaft (42).

When the loading lever (4) rotates counterclockwise from the standby mode in FIG. 5, the drive shaft (42) of the lever heads the reel chassis (7) while sliding along the straight groove (74a) from right to left. When it pushes against the cylinder (11) side and reaches the stop mode shown in Fig. 6, the drive shaft (42)
Is located at the left end of the linear slot (74a), and the drive shaft (42) is rotated even if the loading lever (4) rotates further clockwise.
Does not press the reel chassis (7) by entering the escape slot (74b), and the reel chassis (7) remains stopped.

A cam hole (75) into which the protruding shaft (602) of the pinch roller lever (6) fits is formed in the right front portion of the reel chassis (7).

When the reel chassis (7) slides toward the head cylinder, the protruding shaft (75) is pushed by the edge of the cam hole, and the pinch roller rotates clockwise.

However, as shown in FIG. 5, in the standby mode in which the slide chassis (7) is separated from the head cylinder (11), the cassette (100) is placed on the slide chassis (7).
To load.

As shown by the solid line in FIG. 9, the brake release lever (8)
Release pin (82) enters the cassette and the receiving hole (1) of the brake body (103) is applied to the reel.
04) fit.

The loading motor (12) rotates, the rotating body (3) rotates counterclockwise, and the protrusion (31) of the rotating body (3) rotates the loading lever (4) counterclockwise as described above. , Tape loading is started.

The counterclockwise rotation of the loading lever (4) also advances the reel chassis (7) engaged with the drive shaft (42) of the lever toward the head cylinder (11) side.

By the forward movement of the reel chassis (7), the protruding shaft (602) of the pinch roller lever (6) engaged with the cam hole (75) of the chassis is pressed toward the capstan (14) side, and the pinch roller lever (6). Rotates clockwise and approaches the capstan (14), but at this point the pinch roller (61)
Does not contact the capstan (14).

During this time, the protrusion (31) of the rotating body (3) escapes from the first cutout portion (51) of the mode switching lever (5) and rotates without contact with the lever, so that the mode switching lever (5) is It does not rotate and remains stationary.

When the stop mode shown in FIG. 2 is reached, the protrusion (31) enters the escape portion (44) of the loading lever (4) and hits the mode switching lever (5) to slightly push the lever (5) clockwise. .

When the stem (31) enters the escape part (44), the stem (31)
The loading lever remains stationary even if is rotated further counterclockwise. That is, the tape leading guide (23) (2
In 4), keep the state of being stopped at the tape loading completion position.

Further, when the rotating body (3) rotates counterclockwise to reach the play mode of FIG. 3, the brake drive lever (86) is guided by the elongated hole (55) of the mode switching lever (5) and is rotated clockwise. Turn a little. As a result, the shaft body (84) of the brake release lever (8) in the cassette is pressed against the vertical rod (87) of the brake drive lever (86), and the brake release lever (8) rotates slightly clockwise, Brake release pin (8
At 2), the brake body (103) is separated from the reel against the spring (103), and the brake is released.

Further, the connection plate (57) is slid to the left by the clockwise rotation of the mode switching lever (5), whereby the pressing lever (65) is rotated clockwise, and by the cam surface (67) of the lever. Rotate the crimping lever (62) clockwise and insert the pinch roller lever (6) through the spring (64).
To the capstan (14) side, and press the capstan (14)
Pinch the tape between the pinch roller (61) and the pinch roller (61).

Recording, reproduction and fast-forward reproduction are performed in the play mode.

FIG. 4 shows a rewinding / rewinding reproduction mode in which the rotating body (3) is slightly further rotated counterclockwise from the pull state.

The pressing lever (65) rotates further clockwise than in the pull mode, and the take-up reel stand (72) brake lever (33)
The pressure on the reel side (72) of the take-up reel is weakly applied by the spring force. This causes the tape to be rewound under tension.

Press the standby button (not shown) to
2) is reversed, and the operation reverse to the above returns to the standby mode shown in FIG.

In the embodiment, the mode detecting switch (94) shown in FIG. 10 is attached to the rotating body (3).

The switch (94) is fixed on the main chassis (1) and covers the upper surface of the rotating body (3) on the lower surface of the disk (95). The concentric circular arc-shaped contact patterns (96a) (9)
6b) (96c) is provided, a brush (97) having three contact pieces (97a) (97b) (97c) is fixed on the upper surface of the rotating body (3), and the brush (97) is rotated by the rotation of the rotating body (3). By selectively contacting each contact piece of 97) with each contact pattern of the disc, the rotation angle of the rotating body (3) is detected, and the mode is detected by this, and the loading motor (12) is energized and energized. Control necessary actions such as interruption.

The present invention is not limited to the configuration of the above embodiment, and various modifications can be made within the scope of the claims.

[Brief description of drawings]

1 is a plan view of the mode switching device in the standby mode, FIG. 2 is a plan view of the stop mode of the same as above, FIG. 3 is a plan view of the play mode of the same as above, and FIG. 4 is a plan view of the rewinding / rewinding reproduction mode. 5 and 5 are plan views showing the relationship between the reel chassis in the standby mode and the main chassis, FIG. 6 is a plan view showing the relationship between the reel chassis in the stop mode and the main chassis, and FIG. 7 is a side view of the rotary member mounting portion. Figure, 8th
FIG. 9 is a perspective view of a brake drive lever, FIG. 9 is an explanatory view of a reel brake in a cassette, FIG. 10 is a perspective view of a mode detection switch, and FIG. 11 is a plan view of a conventional mode switching device. (1) ... Main chassis (11) ... Head cylinder (2) ... Tape loading device (3) ... Rotating body (4) ... Loading lever (5) ... Mode switching lever (6) ... Pinch roller lever (8) ... Brake lever

Claims (1)

(57) [Claims] 1. A shaft-shaped protrusion (31) is provided at an eccentric position of a rotating body (3) driven by a motor (12), and the protrusion (3) is provided.
The loading lever (4) and the mode switching lever (5) are provided so that they can be engaged with the loading lever (4).
A tape loading device (2) is connected to the pinch roller lever (5) between the mode switching lever (5) and the capstan (14), and the pinch roller lever (5) is moved by the movement of the mode switching lever (5). A mode switching device characterized in that 6) is pressed against the capstan (14).