JP3520057B2 - Magnetic recording / reproducing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called tape loading device for extracting a tape from a cassette in a magnetic recording / reproducing device such as a video tape recorder (hereinafter, referred to as a VTR). 2. Description of the Related Art Conventionally, as a tape pull-out device employed in a VTR, for example, Japanese Patent Laid-Open Publication No. Sho 60
No. -106058 (G11B 15/665). According to the technique disclosed in the publication, as shown in FIG. 5, a cam gear 2 driven by a gear 1a of a drive motor 1 rotates in a clockwise direction (hereinafter referred to as CW) to engage with a cam groove 2a. The follower pin 3a of the lever 3 that has been
To follow. Accordingly, the pin 3 of the lever 3
Since the slide 4 engaged with b slides in the direction of arrow A,
A pair of left and right tape pull-out arms 5, 6 are biased springs 7,
The tape T is rotated counterclockwise (hereinafter referred to as CCW) and CW while pulling out the tape T from the cassette C by the urging force of No. 8. Reference numerals 9 and 10 are stoppers. As described above, when the rotation of the cam gear 2 is converted into the movement of the slide 4, the ratio of the length from the rotation fulcrum of the lever 3 to the pins 3a and 3b at both ends via the lever 3 is used. , The moving distance of the slide is enlarged. When the relay lever 3 is not used, the radius of the cam gear 2 is set large to secure the required movable distance. In the above-mentioned conventional arrangement, the relay lever is required, so that the arrangement relationship between the cam gear and the slide is separated from each other, and a required space is required. In the latter case, the cam gear must be enlarged in order to increase the movable distance of the slide, or a complicated cam groove must be designed, so that the dead space increases and the design becomes complicated. This is a bottleneck in space-saving designs for such ultra-compact mechanisms. Therefore, in the present invention, a cam gear driven by a driving force of a driving source, first and second slides which reciprocate following the rotation of the cam gear, and a tape from a cassette. A tape pull-out block for storing a tape in a drawer or a cassette; and a tension lever contacting the tape pulled out of the cassette or being stored in an opening of the cassette. After pulling out the tape from the cassette, the tension lever is rotated by the second slide so that the tape comes into contact with the pulled out tape. When loading the tape, the cam gear is rotated by the driving force of the driving motor, and the tape drawer block moves first in the guide groove while pulling the tape from the cassette by the first slide. Thereafter, the cam gear engages the second slide to move the slide forward. A pair of tension levers rotate with the forward movement of the second slide, and come into contact with the pulled-out tape, so that the tape tension can be detected. During unloading,
The rotation of the cam gear causes the tape pull-out block to move back in the guide groove. During the return of the tape drawer block,
The cam gear engages with the second slide and moves backward. With the return of the slide, the pair of tension levers rotate, and are housed in the cassette opening prior to the tape drawer block. Subsequently, the tape drawer block is also housed in the cassette opening, and the tape Loading is completed. DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific embodiment will be described below with reference to the drawings. 1 is a plan view of the tape loading completed state, FIG. 2 is a plan view of the tape unloading state, FIG. 3 is a partial plan view and a sectional view of the cam gear and the slide, and FIG. 4 is a partial plan view of the cam gear and the slide in different states. is there. 1 and 2, reference numeral 11 denotes a cam gear rotatably supported on the rear surface of the main chassis 12.
An operating pin 11a is fixedly implanted on the front side of the cam gear 11, and a cam groove 11b is formed on the rear side. Reference numeral 13 denotes a slide which is disposed on the rear surface of the chassis 12 and slides left and right in the drawing. The slide 13 is provided with a vertical groove 13a and pins 13b and 13c with which the operating pin 11a is engaged. It is looking through the holes 12d and 12e to the upper surface of the chassis 12, and comes into contact with and separates from a tension lever described later. Reference numeral 14 denotes a lock lever rotatably supported by the slide 13 and urged counterclockwise (hereinafter referred to as CCW) by a torsion spring 15,
The lock lever 14 is integrally formed with engaging projections 14a that engage with concave portions (engaged concave portions) 12a and 12b provided in the through hole 12c of the chassis 12, and one end of the lock lever is vertically It is looking out to the groove 13a. 16,1
7 is rotatably supported by shafts 12f and 12g on the upper surface of the chassis 12, and is urged by coil springs 18 and 19 in the CCW and clockwise directions (hereinafter referred to as CW), respectively. Reference numeral 20 denotes a slide which has a follower pin 20a engaged with the cam groove 11b and a linear rack 20b and is slidable on the rear surface of the chassis 12. 21 is a two-stage gear having a gear 21a meshing with the linear rack 20b and a toothless gear 21b;
2 is a toothless gear that meshes with and separates from the second gear 21;
A gear lever that rotates integrally with the step gear 21, 24 is a gear lever that rotates integrally with the toothless gear 22, 25 is a link connected to the gear lever 23, and 26 is a link connected to the gear lever 24. 27 and 28 are link 2 respectively
5 and 26, which are tape pull-out blocks that slide in guide grooves 29a and 29b provided in the sub-chassis 29. The tape pull-out blocks 27 and 28 have vertical posts 30, 31 and inclined posts 32, 33, respectively. Is provided. 34a and 34b are catchers, 35 is a cylinder, 36 and 37 are supply side and take-up side reel stands, 38a and 38b are cassette guides (positioning pins), 39 is a capstan, 40a, 40b, 40c, and 40c.
40d is a fixed roller guide, C is a cassette T
Is a tape. In addition, 12h, 12i, and 12j are guide pins and bosses provided on the rear surface side of the chassis 12. Next, the operation of the mechanism having the above configuration will be described. Now, in the state of FIG. 2 where the cassette C is mounted,
For example, when a reproduction operation is performed, a loading motor (not shown) rotates, and the rotational driving force of the motor drives the cam gear 11 to rotate to the CCW via a reduction gear (not shown). The rotation of the cam gear 11 causes the follower pin 20a to follow the cam groove 11b and slide the slide 20 diagonally rightward in the drawing, thereby rotating the second-stage gear 21 and the toothless gear 22 to CW and CCW, respectively. As the gears 21 and 22 rotate, the gear levers 23 and 24 and the links 25 and 26
The tape pull-out blocks 27 and 28 pull out the tape T from the cassette C through the guide grooves 29a and 29b.
Is slid upward in the drawing. As shown in FIG.
When the cam gear 11 rotates the CCW by the angle θ0, the operating pin 11a moves to the position of 11a '. Further cam gear 1
Due to the rotation of 1, the operating pin 11a engages with the vertical groove 13a of the slide 13 and abuts on the lock lever 14, and the lock lever 14 is turned to CW against the bias of the torsion spring 15 to lock the lock. The engagement between the engagement projection 14a of the lever 14 and the engagement recess 12a of the chassis 12 is released, and the slide 13 can be moved rightward in the drawing.
The slide 13 is slid into the vertical groove 13a,
4A, the operating pin 11a is separated from the vertical groove 13a at the position shown in FIG. 4B. The moving distance L of the slide during this time
Is 2R sin θn. Where R is the cam gear 1
The distance θn from the center P0 of the cam gear 11 to the center of the operation pin 11a is a straight line Y perpendicular to the moving direction of the slide 13 from the center P0 of the cam gear 11, and the point (11a ') at which the operation pin 11a engages with the vertical groove 13a. And a straight line connecting the center P0 of the cam gear 11 with the straight line. Therefore, for θn = 0 to 90 °, the moving distance L is 0 to 2R, and conventionally, the maximum moving distance by the cam groove of the cam gear is the radius of the cam gear, but in the present invention, the maximum diameter of the cam gear 11 is Is obtained. Operation pin 11a from vertical groove 13a
Is released, the lock lever 14 rotates to the CCW by the urging force of the spring 15, and the engagement protrusion 14a is re-engaged with the engaged concave portion 12b of the chassis 12, so that the slide 13 is locked at that position. Due to the sliding of the slide 13 to the right, the tension levers 16 and 17 stopped at the positions shown in FIG.
Are rotated to CCW and CW, respectively, as the pins 13b and 13c of the slide 13 move rightward, come into contact with the tape T that has already been drawn out, expand the tape T, and finally , The tension of the running tape T is detected by rotating to the position shown in FIG. While the operating pin 11a moves the slide 13, the slide 20 slides, and the tape T is pulled out by the tape pull-out blocks 27 and 28.
4a and 34b, the tape T is wound around the cylinder 35 at a predetermined angle, and the tape loading is completed.
State. Finally, a pinch roller (not shown)
Presses against the capstan 39 across the tape T. FIG.
As shown in FIG. 7, in the unloading state, in the unloading state, the tension levers 16 and 17 are superposed on the tape pull-out blocks 27 and 28 in the opening (not shown) of the cassette C. At the start,
The movement of the slide 13 is shifted from the start of the movement of the slide 20 by a time difference θ0 (FIG.
(Refer to (a)), and the tape drawer block 27,
28 pulls out the tape T in advance, and pulls out the tape T to the outside of the turning radius of the tension levers 16 and 17.
After the movement of the slides 7 and 28, the slide 13 is moved and the tension levers 16 and 17 are rotated to save the space of the mechanism. The operating pin 11a
Each of the operation modes of the tape is performed in a state in which the slide 13 has been removed from the vertical groove 13a and the slide 13 is locked. At the time of unloading the tape, the tension levers 16 and 17 are first stored in the opening of the cassette C while the tape T is wound on either the supply reel base 36 or the take-up reel base 37, and then the tape is pulled out. Block 27, 2
8 are stored therein, and perform an operation completely opposite to the above-described operation at the time of tape loading. According to the present invention, the two slides are sequentially driven by one cam gear to control the tape pull-out and the tape tension lever, thereby eliminating the need for a relay lever, simplifying the structure of the mechanism, and Effective for saving space.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a tape loading completed state. FIG. 2 is a plan view showing a tape unloading state. FIG. 3 is a partial plan view and a sectional view of a cam gear and a slide. FIG. 4 is a partial plan view showing different states of a cam gear and a slide. FIG. 5 is a plan view of a conventional tape unloading state. [Description of Signs] 11 Cam gear 11a Operating pin 12a Engaged concave portion 13 (First) slide 13a Vertical groove 14 Lock lever (biasing means) 14a Engagement projection 16 Tension lever 17 Tension lever 20 (Second) Slide 27 Tape drawer block 28 Tape drawer block

Claims (1)

(57) Claims: 1. A cam gear (11) driven by a driving force of a driving source, and first and second slides (20) that reciprocate following the rotation of the cam gear. (13), a tape pull-out block (27) (28) for pulling out a tape from the cassette or storing the tape in the cassette;
A tension lever (1) which comes into contact with the tape pulled out of the cassette or is stored in the opening of the cassette.
6) and (17), wherein the first slide (20)
After the tape pull-out blocks (27) and (28) pull out the tape from the cassette, the tension lever is rotated by the second slide (13) and comes into contact with the pulled-out tape. The second slide (13) has a vertical groove (13a) orthogonal to the moving direction, the cam gear (11) has an operating pin (11a) engaging with the vertical groove, A biasing means (14) for biasing a pin toward the center of the cam gear along the vertical groove, wherein after the first slide moves by a predetermined amount due to the rotation of the cam gear, the operating pin moves to the vertical position; A magnetic recording / reproducing device which is engaged with a groove.