JPS6251Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tape loading device for a video tape recorder.

Generally, in a video tape recorder (VTR), as schematically shown in FIG.
This tape 2 is scanned by the head (not shown) of the drum 3 in a direction crossing the running direction of the tape 2, thereby recording a video signal on the tape 2 or reproducing a video signal from the tape 2. Are known. The above tape 2 is the hub 4 of cassette 1.
It is wrapped around a and 4b. 5a and 5b are tape guides, and these guides 5a and 5b are respectively implanted in arms 6a and 6b, and these arms 6a and 6b are rotatable on a substrate (not shown) using 7a and 7b as fulcrums, respectively. installed on. The tape guides 5a and 5b are tapered so as to guide the tape 2 along the circumferential surface of the drum 3 (not shown in the slanted state in the figure), which is mounted at an angle with respect to the substrate. It has a taper angle suitable for Chain lines 6'a and 6'b indicate the positions of the arms 6a and 6b before the tape 2 is pulled out, and when the arms 6a and 6b are rotated to the positions shown by solid lines, the tape 2 is pulled out from the cassette 1. The tape 2 that has been pulled out is transferred to the drum 3.
The erasing head 8 has a full width along the circumference of the
and a tape running path that surrounds the head 9 for recording and reproducing audio signals and recording and reproducing control signals. 10 is a capstan, the tape 2 is pressed against it by a pinch roller 11, and the tape 2 is run at a constant speed by the capstan 10. The tape 2 running at a constant speed is wound up by the hub 4b. 12 is a tension pin implanted in a tension arm (not shown). 1
3 and 14 indicate tape guides in the cassette 1.

When tape 2 is pulled out as shown above,
The tape guides 5a, 5b are pressed against the V-grooves of the guide receivers 15a, 15b fixed to the substrate, and the tape guides 5a, 5b are held in a stable state.

The present invention allows the tape guide to be smoothly pressed into contact with the guide receiver, and to maintain a predetermined position on the movable member such as the arm even when the tape guide is moved away from the guide receiver to draw out the tape (or store the tape). This is to prevent damage to the tape, which will be described later, during the movement.

An embodiment in which the present invention is applied to a so-called VHS system VTR will be described in detail below with reference to FIGS. 2 to 5.

Figure 2 shows the head drum 3 and tape guide 5.
a, the arm (movable member) 6a, the fulcrum 7a, and the guide receiver 15a are schematically shown, and the head drum 3 has head tips 16a, 16b as is well known.
It is composed of a rotating upper drum 17 to which a tape guide step 18 is attached, and a fixed lower drum 19 having a tape guide stepped portion 18 formed thereon. The tape guide 5a includes an inclined tape guide pole 20 instead of the tapered one shown in FIG. part 22 and second contact part 23
and a third contact portion consisting of a pin 24 that is pressed against the guide receiver 15a and regulates the axial position of the roller 21 in the tape guide 5a, and the pin 24, the contact portions 22, 23, and Paul 2
0 is fixed to the base 25, and the roller 21 is fixed to the base 25.
It is rotatably mounted on the Further, a cylindrical protrusion 26 is formed on the base body 25, and a protrusion piece 27 is integrally formed with the protrusion. This protrusion 2
A pin 28 implanted in the arm 6a is loosely fitted into the arm 6a as shown in detail in FIGS.
0 (details shown in FIG. 5) and is loosely fitted into the narrow diameter portion 29 to restrict removal. 32 is a spring, and the above-mentioned protruding piece 2
7 and the arm 6a.

The guide receiver 15a has a receiving portion 33 made of a groove into which the pin 24 is inserted and abutted, and receiving portions 34 and 35 made of a V-groove into which the abutting portions 22 and 23 are pressed against each other. .

In the above-mentioned loading device, when the tape is pulled out from the cassette as described above, the arm (movable member) 6a is rotated clockwise in FIG. 2 by a well-known power source such as a motor (not shown). Due to this rotation, the edge of the elongated hole 30 of the tape guide 5a is pressed by the pin 28, so that the contact parts 34, 35 and the pin 24 are pressed against the receiving parts 33, 34, 35 of the guide receiver 15a, respectively. , the tape guide 5a is in a fixed state when the tape is pulled out. In this state, the receiving portions 33, 3
Since the pressing point pressed by the pin 28 of the elongated hole 30 is located within the triangle having vertices 4 and 35, the tape guide 5a is stably pressed against the guide receiver 15a by this pressing.

The receiving parts 34 and 35 are shaped like V-grooves, and regulate the position of the tape guide 5a in a direction substantially perpendicular to the axial direction of the roller 21 in the tape guide 5a and the pressing direction by the arm 6a, respectively. . The receiving portions 34 and 35 are constituted by two surfaces for forming the V-groove, that is, two surfaces that intersect with each other and are brought into contact with the contact portions 22 and 23.

In the above-described apparatus, during the tape drawing period when the tape guide 5a is not in pressure contact with the guide receiver 15a, the tape guide 5a is biased by the spring 32, and the upper part of the protruding part 26 is pressed against the large diameter part of the pin 28.
0 end. In this placed state, the tape guide 5a, that is, the roller 21 is moved by the arm 6a.
, and the state is lower than the above-mentioned state in which the tape has been drawn out.

By the way, in a so-called VHS system VTR, the tape 2 along the drum 3 in FIG.
3. A tape path is formed at the same height from the tension pin 12 to the head drum 3 to the tape guide 5a. If this height is used as the reference height, the tape path gradually increases from the tape guide 5a to the vicinity of the point where the tape 2 touches the head drum 3. After that, the height gradually increases along the head drum 3, returns to the above reference height at the center of the drum 3, and further gradually increases to the vicinity away from the head drum 3.
As the tape 2 leaves the head drum 3 and reaches the tape guide 5b, it gradually becomes lower, returns to the reference height at the tape guide 5b, and then wraps around the head 9, capstan 10, and guide 14 at this height. A tape path is formed.

In the above-described VTR shown in FIG. 1, the height of the tape 2 regulated by the guide receiver 15a of the tape guide 5a is higher than the height of the tape 2 near the head drum 3. Also, while the tape guide 5a is moving from the position shown by the chain line to the position shown by the solid line, or in the opposite direction,
The tape guide 5a regulates the tape 2 to approximately a reference height. Therefore, the tape guide 5a
When the tape 2 is pulled out and returned by the tape guide 5a, the tape 2, which is regulated to a reference height by the tape guide 5a, passes near the area where the tape 2 touches the head drum 3. At this time, the head tips 16a and 16b may rub against the lower edge of the tape 2 and damage the tape.

In the present invention, the tape guide 5a is connected to the guide receiver 1.
5a, the position of the roller 21 is lowered by the spring 32, so that the lower edge of the tape 2 whose height is regulated by the roller 21 is at the head tip 1 described above.
6a, 16b, and therefore there is no risk that the lower edge of the tape 2 will be rubbed by the head tips 16a, 16b.

As mentioned above, by providing the spring 32,
It is possible to prevent the tape guides 5a and 5b from wobbling while they are moving, and it is possible to eliminate the unstable state of the tape when the tape is pulled out or pulled in, especially in a portable VTR.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing a conventional example, Figs. 2 to 5 show an embodiment of the present invention, Fig. 2 is a perspective view, Fig. 3 is a side view, and Fig. 4 is a front view. Figure, 5th
The figure is a plan view. 1: Cassette, 2: Tape, 3: Head drum, 6a, 6b: Arm, 5a, 5b: Tape guide, 15a, 15b: Guide receiver.

Claims (1)

[Scope of utility model registration request] A tape guide that is moved to pull out the tape in a device that pulls out a tape stored in a cassette and wraps it around the circumferential surface of a head drum;
The tape guide is provided with a guide receiver for receiving the tape guide in a state in which the drawn-out tape is wrapped around the circumferential surface of the head drum, and a movable member to which the tape guide is attached, and the tape guide is connected to the movable member. The tape guide is attached with some play, and the tape guide has a first part that comes into contact with the guide receiver.
A contact portion, a second contact portion, and a third contact portion are formed, and the point at which the tape guide is pressed by the movable member is the first contact portion, the second contact portion, and the third contact portion. The tape guide is disposed within a triangle having the third contact portion as its apex, and has a spring that biases the tape guide in a predetermined direction with respect to the movable member, and the tape guide is separated from the guide receiver. A tape loading device for a video tape recorder, wherein the tape guide is pressed to a predetermined position on the movable member by the spring when the tape is loaded.