JPH0237190Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is a tape cassette suitable for use, for example, in a video tape recorder. This invention relates to a tape cassette which is constructed such that it is always elastically pressed by a reel presser pin.

[Conventional technology]

A conventional example of this type of tape cassette for a video tape recorder is, for example, Japanese Utility Model Publication No. 54-53000.

As shown in FIG. 3, in this conventional example, a reel 4 is rotatably housed in a cassette housing 3 consisting of upper and lower halves 1 and 2, and a reel holding pin 6 is inserted into a through hole 5 provided in the upper half 1 in the upper and lower parts. The reel presser pin 6 is movably inserted between the upper half 1 and a flange 7 that is integrally provided at the lower end of the reel presser pin 6. A tape cassette 10 is formed by pressing a steel ball 9 provided on the upper surface of the center portion of a reel 4 from above.

As is well known, a pair of left and right reels 4 are disposed within the cassette housing 3, and a magnetic tape 11 is wound around both reels 4 and stored therein. A pair of left and right reel holding pins 6 and compression coil springs 8 are also provided corresponding to the upper portions of both reels 4. Furthermore, each reel 4 has upper and lower reel flanges 13 and 14 at both upper and lower ends of the reel hub 12.
The lower end 12 of the reel hub 12
a is the reel stand insertion hole 15 provided in the lower half 2
inserted inside. In addition, a reel shaft engagement hole 1 opened at the lower end side of the central part of the reel hub 12.
6, and a plurality of reel drive pawl engagement grooves 17 are provided on the inner periphery of the reel shaft engagement hole 16.

When this tape cassette 10 is not in use,
The lower reel flange 14 of the reel 4 is elastically pressed onto the upper surface 2a of the lower half 2 by the spring force of the compression coil spring 8 that presses the reel holding pin 6 downward, and the reel 4 is held in the cassette housing 3. I try to suppress the wobbling of the top and bottom.

In use, this tape cassette 10 is inserted into a cassette holder 19 of a video tape recorder (not shown) and mounted at the cassette mounting position, as shown in FIG. mounted on top. That is, reel stand 2
0 is inserted into the reel shaft engagement hole 16 and the plurality of reel drive claws 22 on the outer periphery of the reel shaft 21 are engaged with the reel drive claw engagement grooves 17. The lower end 12a is placed on the upper surface 20a of the reel stand 20, the lower reel flange 14 of the reel 4 is lifted upward from the upper surface 2a of the lower half 2, and the reel 4 can freely rotate within the cassette housing 3. It becomes like this.

In this case, in a horizontal use machine in which the tape cassette 10 is mounted horizontally from above to the cassette mounting position, the reel 4 is reeled only by the spring force of the compression coil spring 8 that presses the reel holding pin 6 downward. It can be pressed relatively stably on the table 20.

On the other hand, in a vertical use machine in which the tape cassette 10 is mounted vertically from the side to the cassette mounting position, as shown in FIG. The reel 4 is pressed by the pressing member 25 of 24, and the reel 4 is stably pressed onto the reel stand 20 by the two spring forces of the spring 26 and the compression coil spring 8 that press the pressing member 25. has been done.

[Problem that the invention attempts to solve]

However, in this conventional example, since the reel presser pin 6 is guided only by the inner circumferential surface of the through hole 5, the reel presser is The pin 6 was likely to become loose within the through hole 5. Particularly, in a machine used vertically as shown in FIG. This caused the reel presser pin 6 to be unable to accurately press the upper surface of the central portion of the reel 4 from the axial direction of the reel 4, which had a significant adverse effect on the rotation of the reel 4. In the conventional example, the wall thickness A of the through-hole peripheral portion 1a of the upper half 1 was made as thick as possible to minimize the above-mentioned wobbling of the reel presser pin 6, but on the other hand, the compression coil The effective stroke B of the spring 8 becomes small, and due to variations in the overall heights C and D of the tape cassette 10 and reel stand 20, the pressing force of the reel 4 onto the reel stand 20 tends to vary significantly, making it difficult to maintain a stable pressing force. There was a problem that was difficult to obtain.

The present invention makes it possible to prevent rattling of the reel holding pin as much as possible, and also to make the effective stroke of the compression coil spring as large as possible.

[Means for solving problems]

The present invention provides the above-mentioned tape cassette.
A guide tube is integrally provided around the through hole on the lower surface of the upper half, and a guided tube, which is integrally provided on the outer periphery of a flange that is integrally provided at the lower end of the reel presser pin, is inserted into the guide tube. This tape cassette is characterized in that it is configured to be guided so as to be vertically movable.

[Effect]

The present invention allows the reel presser pin to move between the through hole and the guide tube by vertically guiding the guided tube provided on the outer periphery of the lower end of the reel presser pin with the guide tube provided on the lower surface of the upper half. In addition to being supported at two points above and below, the guide tube guides the guided tube whose diameter is sufficiently larger than the reel holding pin.
The reel presser pin can be guided extremely stably, and wobbling of the reel presser pin can be prevented as much as possible. Since rattling of the reel holding pin can be prevented regardless of the wall thickness around the through hole in the upper half, the wall thickness around the through hole in the upper half can be made as thin as possible to increase the effectiveness of the compression coil spring. The stroke can be made as large as possible.

An embodiment in which the present invention is applied to a tape cassette for a video tape recorder will be described below with reference to FIGS. 1 and 2. Note that the same reference numerals are given to the same structural parts as in the conventional example shown in FIG. 3, and the explanation thereof will be omitted.

First, in FIG. 1, a flange 30 is integrally provided at the lower end of a reel presser pin 29 molded from synthetic resin, and a cylindrical guided tube 31 is provided on the outer periphery of the flange 30. It is provided integrally in an axial state. The reel holding pin 29 is inserted from below into a through hole 5 provided in the upper half 1 and is configured to be vertically movable. At this time, a cylindrical guide cylinder 32 is integrally provided on the lower surface of the upper half 1 molded from synthetic resin and in the penetrating peripheral part 1a so as to be coaxial with the through hole 5. 31 is inserted into the guide tube 32 and guided so as to be vertically movable. The compression coil spring 8 is provided on the outer periphery of the reel presser pin 29 between the flange 30 and the upper half 1, and presses the reel presser pin 29 downward to release the flange 30.
is pressed onto the steel ball 9 on the upper surface of the center portion of the reel 4 from above. Both upper and lower ends of the compression coil spring 8 are positioned by positioning ribs 33 and 34 that are integrally provided on the through-hole peripheral portion 1a and the flange 30. Further, a locking pawl 35 is integrally provided on the outer periphery of the upper end of the reel presser pin 29, and a hollow portion 36 with an open upper end and a slit 37 are formed in the center of the reel presser pin 29. This reel holding pin 29 is inserted from below into the through hole 5 against the elastic force of its upper end, and is attached with one touch to lock the locking claw 35 on the peripheral portion 1a of the through hole.

According to the present invention, the guided tube 31 is connected to the guide tube 3.
By allowing the guide to move vertically at 2,
The reel holding pin 29 can be supported at two points above and below, the through hole 5 and the guide cylinder 32, and the guide cylinder 32 stabilizes the guided cylinder whose diameter is sufficiently larger than that of the reel holding pin 29. can be guided extremely stably, and wobbling of the reel holding pin 29 can be prevented as much as possible.

Therefore, as shown in FIG. 1, even in a vertical machine in which the tape cassette 10 is mounted vertically at the cassette mounting position, the reel crimping mechanism 2 is
4 and the steel ball 9 on the upper surface of the central portion of the reel 4, the reel presser pin 29 does not twist at all, and the reel presser pin 29 presses the upper surface of the central portion of the reel 4 on the reel 4. It is possible to always press accurately from the axial direction. As a result, the press-bonding posture of the reel 4 onto the reel stand 20 becomes extremely stable, and the rotation of the reel 4 rotationally driven by the reel stand 20 becomes extremely stable.

Moreover, it is possible to prevent the reel presser pin 29 from wobbling regardless of the wall thickness E of the through-hole peripheral portion 1a of the upper half 1, so that the through-hole peripheral portion 1a of the upper half 1 can be prevented from wobbling.
By making the wall thickness of a as thin as possible, the effective stroke F of the compression coil spring 8 can be made as large as possible. As a result, the spring constant of the compression coil spring 8 can be made as small as possible, and the tape cassette 1
Even if there is some variation in the overall heights C and D of the reel stand 20, the variation in the pressing force of the reel 4 onto the reel stand 20 can be minimized, and the reel 4 can always be placed on the reel stand 20. Appropriate crimping force can always ensure stable crimping.

Note that FIG. 2 shows a modified example, and
A locking pawl 39 is integrally provided on the outer periphery of the upper end of the guided tube 31, and the locking pawl 39 is configured to lock onto a circular rib 40 that is integrally provided on the inner periphery of the lower end of the guide tube 32. It is. In this case,
A plurality of slits 41 are provided in either the guide cylinder 32 or the guided cylinder 31 so that the locking pawl 39 can be inserted from below above the circular rib 40 with one touch by utilizing the resulting elastic force. do.

Although the embodiments of the present invention have been described above, the present invention is not limited to the embodiments, and various effective changes can be made based on the technical idea of the present invention.

Further, the present invention is not limited to tape cassettes for video tape recorders, but can be applied to various tape cassettes used in various magnetic recording and reproducing devices.

[Effect of idea]

This invention can prevent the rattling of the reel holding pin as much as possible, and can also make the effective stroke of the compression coil spring as large as possible, so the reel can always be stably crimped onto the reel stand, and the reel can be rotated extremely stably at all times.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a main part showing an embodiment of a tape cassette for a video tape recorder to which the present invention is applied, and FIG. 2 is a cross-sectional view of a main part showing a modification of the same. FIG. 3 is a sectional view of the main parts of a conventional tape cassette for a video tape recorder. In the symbols used in the drawings, 1...upper half, 1a...through hole periphery, 2...lower half, 3...cassette housing, 4...reel, 5...
Through hole, 8... compression coil spring, 29... reel presser pin, 30... flange, 31... guided tube, 32... guide tube.

Claims (1)

[Scope of utility model registration request] A reel is rotatably stored in a cassette housing consisting of an upper and lower half, and a reel holding pin is inserted into a through hole provided in the upper half so as to be movable up and down.
The reel presser pin presses the upper surface of the central portion of the reel from above using the spring force of a compression coil spring provided on the outer periphery of the reel presser pin between the flange integrally provided at the lower end of the reel presser pin and the upper half. In the tape cassette, a guide cylinder is integrally provided around the through hole on the lower surface of the upper half,
A tape cassette characterized in that a guided cylinder integrally provided on the outer periphery of the flange of the reel presser pin is inserted into the guide cylinder and guided so as to be vertically movable.