JPH0627005Y2 - Tape recording / reproducing mechanism of magnetic recording / reproducing apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a tape loading mechanism of a magnetic recording / reproducing apparatus.

[Conventional technology]

4 to 6 show a tape loading mechanism of a conventional magnetic recording / reproducing apparatus used in, for example, a Mitsubishi Electric VTR, HV-69D, where (1) is chassis and (2) is magnetic. Rotating drums with heads, (3) and (4) are tape pull-out members, and guide grooves (5) and (5) formed on the chassis (1), respectively.
It is slidably attached to (6). (7) and (8) are loading links, each consisting of two arms,
One end is engaged with the tape pull-out members (3), (4), respectively, and the other end is connected to the gears (9), (10) with the spring (11),
It is attached via (12). Gears (9), (10)
Are rotatably supported by shafts (13) and (14) on the chassis (1) and mesh with each other. (15) is a cam gear having a cam groove (16), which is rotatably supported by a shaft (17) on the substrate and meshes with a small gear (18) which rotates coaxially with the gear (9). (19) is a disc cam driven by a motor (not shown), (20) is a swing arm, and the middle part is swingably supported by a shaft (21) on the chassis (1), One end of the disk cam (1
9) is engaged with the groove (19a) and the other end is engaged with the cam groove (16) of the cam gear (15) by the pin (23).
(24) and (25) are stoppers.

Next, the operation will be described. Fig. 4 is a back view showing the tape pull-out members (3), (4) in the first position where the magnetic tape in the cassette can be pulled out, that is, the state before loading, and Fig. 5 shows the magnetic tape outside the cassette. FIG. 6 is a back view showing a second position where the magnetic head can be pulled out and attached to the magnetic head, that is, a state in which loading is completed. When loading starts in FIG. 4, the swing arm (20) follows the rotational movement of the disc cam (19) in the counterclockwise direction (the direction of the arrow (26)) with the shaft (21) as a fulcrum. Arrow (2
Performs rocking motion in the direction of 7). This swinging motion is caused by the engagement of the first groove portion (16a) of the cam groove (16) of the cam gear (15) and the pin (23) with the arrow (2) of the cam gear (15).
Converted to rotational movement in the direction of 8), and gears (9), (10)
And the tape pull-out members (3), (4) through the loading links (7), (8) along the guide grooves (5), (6), and the arrow (29).
Slide in the direction of to the second position. Even if the tape pull-out members (3) and (4) come into contact with the stoppers (24) and (25), the gears (9) and (10) continue to rotate, so that the springs (11) and (12) are displaced. Then, the tape pull-out members (3) and (4) are pressed and fixed to the stoppers (24) and (25) by a pressing load corresponding to the displacement load. In the loading completed state shown in FIG. 5, the pin (2) of the swing arm (20) is
3) The engaging portion moves from the first groove portion (16a) of the cam groove (16) of the cam gear (15) to the second groove portion (16b) formed in a substantially arc shape centering on the shaft (21). By doing so, the rotational torque by the springs (11) and (12) is prevented from being applied to the swing arm (20) and the disc cam (19).

The engagement relationship between the cam gear (15) and the swing arm (20) is shown in detail in FIGS. 6 (a) and 6 (b).
FIG. 6 (a) shows the state of FIG. 4 in which the tape pull-out members (3), (4) are in the first position, and the pin (23) is the first groove portion (16a) of the cam groove (16). Is engaged with. Fig. 6
(b) shows the state of FIG. 5 in which the tape pull-out members (3), (4) are in the second position, and the pin (23) is in the cam groove (1
It engages with the 2nd groove part (16b) of 6).

Although the above description has explained the operation during loading, the operation during unloading is the reverse of the above description. That is, the disc cam (19) rotates clockwise in FIG. 5, and the cam gear (15), gears (9), (10) are transmitted in rotation in response to the swing of the swing arm (20). And the tape pull-out members (3) and (4) are moved from the second position to the first position.
It moves to the position and returns to the state shown in FIG.

[Problems to be solved by the invention]

In the tape loading mechanism of the conventional magnetic recording / reproducing apparatus, the pressing springs (11), (1) are provided between the gears (9), (10) and the loading links (7), (8) at the second position.
Since the locking position accuracy is secured by pressing and fixing the tape pull-out members (3) and (4) to the stoppers (24) and (25) with the interposition of (2), the stop position error on the drive source side is secured. However, since the pressing spring mechanism is not provided in the first position, the stop position accuracy of the tape pull-out members (3) and (4) is the tape pull-out on the driven side from the disc cam (19) which is the drive source. Due to the influence of the accumulated error of all components interposed in the driving force transmission path to the member, it is not possible to sufficiently secure the error. Therefore, when the cassette is installed or removed, the guide posts, which are erected on the tape pull-out members (3) and (4), may come into contact with the magnetic tape inside the cassette and damage the magnetic tape. .

The present invention has been made to solve the above-mentioned problems, and it is possible to accurately perform stop positioning not only at the second position but also at the first position of the tape pull-out member with a simple mechanism. An object of the present invention is to obtain a tape loading mechanism for a magnetic recording / reproducing apparatus, which is less likely to damage the magnetic tape when it is taken out or taken out.

[Means for solving problems]

In the tape loading mechanism of the magnetic recording / reproducing apparatus according to the present invention, the cam groove of the cam gear is centered on the swing fulcrum of the swing arm at both the first position and the second position of the tape pullout member. It is formed so as to have a substantially arc shape.

[Action]

In this invention, the relationship between the swing motion of the swing arm and the rotary motion of the cam gear is such that the cam gear is stopped even if the swing arm rotates at both ends of the motion, so that the drive source is driven by the cam gear. An error in the stop position of a component near the side does not affect the driven side.

[Example of device]

An embodiment of the present invention will be described below with reference to FIGS. Fig. 1 is a back view showing the state before loading,
FIG. 2 is a back view showing the completion of loading, and FIG. 3 is a view showing the relationship between the cam gear and the swing arm.
The drawing corresponding to the figure and (b) are the figures corresponding to FIG. 2, and the same parts as those of the above-mentioned conventional device are designated by the same reference numerals and the description thereof will be omitted. Reference numeral (16A) denotes a cam groove provided in the cam gear (15), and a first groove portion (16a) formed in a substantially arc shape centering on the pin (21) when in the first position, and the first groove portion. A second groove portion (16b) formed in a substantially arc shape centering on the pin (21) when connected to the outer side of the (16a) and in the second position, and a third groove connected to the inner side of the first groove portion (16a). It is composed of a groove (16c).

Next, the operation will be described. Tape pull-out member (3),
In Fig. 1 and Fig. 3 (a) where (4) is in the first position, the pin (2
Since 3) is engaged with the first groove portion (16a) of the cam groove (16A), the cam gear (15) is not related to the stop accuracy even if the stop angle accuracy of the swing arm (20) is poor. Instead, it stops at a certain angle.

Next, when loading starts in FIG. 1, the disc cam (19) rotates counterclockwise (in the direction of arrow (26)), and in response to this, the swing arm (20) moves in the direction of arrow (2).
It swings in the direction of 7) and the pin (23) is in the cam groove (16A).
The engagement position is moved from the first groove portion (16a) to the third groove portion (16c). Since the third groove portion (16c) is not formed in an arc shape centering on the pin (21), the cam gear (15) is moved to the arrow (2) by the swing of the swing arm (20).
8), the tape pull-out members (3), (4) pass through the gears (9), (10) and follow the guide grooves (5), (6) in the direction of the arrow (29). Slide it to the 2 position. Further, the cam gear (15) rotates, and the pin (23) moves to the cam groove (16
In A), from the third groove portion (16c) to the first groove portion (1
6a), but at this point the first groove (16a)
Is not in an arcuate position around the pin (21), the cam gear (15) continues to rotate. The tape pull-out members (3) and (4) are connected to the stoppers (24) and (25).
Since the disc cam (19) continues to rotate even if it abuts against the spring, the springs (11) and (12) are displaced and the tape pull-out members (3) and (4) are displaced by the pressing load corresponding to this displacement load. ) Is pressed and fixed to the stoppers (24) and (25). When the loading is completed as shown in FIG. 2, the pin (23) moves into the cam groove (16).
In A), from the first groove portion (16a) to the second groove portion (16
By moving the engagement point to b), the spring (11),
The rotational torque due to (12) is prevented from being applied to the swing arm (20) and the disc cam (19).

The engagement relationship between the cam gear (15) and the swing arm (20) is shown in detail in FIGS. 3 (a) and 3 (b).
FIG. 3 (a) shows the state of FIG. 1 in which the tape pull-out members (3), (4) are in the first position, and the pin (23) is the first groove portion (16a) of the cam groove (16A). Is engaged with. Third
Figure (b) shows the state of Figure 2 in which the tape pull-out members (3), (4) are in the second position, and the pin (23) is in the cam groove (1
6A) is engaged with the second groove portion (16b).

Although the above description has described the operation during loading, the operation during unloading is the reverse of the above description. That is, the disc cam (19) rotates clockwise in FIG. 2, and the cam gear (15), gears (9), (10) rotate in response to the swing of the swing arm (20). The tape pull-out members (3) and (4) are transmitted, and are moved from the second position to the first position to return to the state shown in FIG. At this time, since the pin (23) engages with the first groove portion (16a) of the cam groove (16A), the cam gear (15) does not affect the stopping accuracy of the swing arm (20) and the cam gear (15) has a constant angular position. You can stop at.

In the above embodiment, the cam groove (16A) composed of the first groove portion (16a), the second groove portion (16b), and the third groove portion (16c) is shown, but the first position and the second position
Two or one groove portion may be used as long as it has a groove shape formed in a substantially arcuate shape with the rocking fulcrum of the rocking arm (20) at the position.

Further, although the M loading method of the VHS method VTR has been described in the above embodiment, it goes without saying that the present invention can also be applied to a tape loading mechanism in a DAT (digital audio tape recorder) or other magnetic recording / reproducing apparatus.

[Effect of device]

As described above, this invention can accurately perform stop positioning not only at the second position but also at the first position of the tape pull-out member with a simple mechanism, and may damage the magnetic tape when the cassette is attached or removed. There is an effect that there is little.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, which is a rear view showing a state before loading, FIG. 2 is a rear view showing a completed state of loading, and FIG. 3 shows a relationship between a cam gear and a swing arm. In the figure, (a) is a figure corresponding to FIG. 1 and (b) is a second figure.
FIG. 4 is a back view showing the state of the conventional mechanism before loading, FIG. 5 is a back view showing the completed state of loading, and FIG. 6 shows the relationship between the cam gear and the swing arm. In the figure, (a) is a diagram corresponding to FIG. 4 and (b) is a diagram corresponding to FIG. In the figure, (2) is a rotary drum, (3) and (4) are tape drawing members, (5) and (6) are guide grooves, (15) is a cam gear,
(16A) shows a cam groove, (19) shows a disc cam, (20) shows a swing arm, and (21) shows a swing fulcrum. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] 1. A magnetic recording / reproducing apparatus of a system in which a magnetic tape is loaded on a rotary drum provided with a magnetic head over a predetermined angle, and the magnetic tape is sprinkled on the magnetic head to record or reproduce a signal. A first swinging arm that swings when driven by a motor; a cam gear that has a cam groove that engages with the swinging arm; and a rotation of the cam gear that pulls out the magnetic tape from the cassette. A tape pull-out member reciprocating between a position and a second position where the magnetic tape can be pulled out of the cassette so as to be abutted on the magnetic head, and the cam groove has the first position and the second position. A tape loading mechanism for a magnetic recording / reproducing apparatus, wherein the tape loading mechanism is formed in a substantially arcuate shape around a swing fulcrum of the swing arm.