JP2002364691A - Coil spring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compression coil spring capable of being manufactured at a low cost and stably placed on a support member. SOLUTION: This compression coil spring is used when the end part thereof cannot be wound inside. The end part of the compression coil spring is not ground and has, at the end face thereof, a final end turn part of a half turn or more of coil in the direction orthogonal to the center line of the spring. The coil spring may be suitably used for a, so-called, one reel type magnetic tape cartridge. The coil spring (compression coil spring) should desirable be formed so as to have the final end turn part of a half turn to three fourth turn of coil in the direction orthogonal to the center line of the spring provided at the end part of the spring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil spring, and more particularly to a coil spring that can be suitably used for a magnetic tape cartridge or the like. The term "magnetic tape cartridge" used herein means a tape reel around which a magnetic recording tape (hereinafter, simply referred to as "magnetic tape") is rotatable, in a case housing formed by combining an upper half and a lower half. Typified by a magnetic tape cartridge housed in the cartridge.

[0002]

2. Description of the Related Art There are various types of magnetic tape cartridges in which a tape reel wound with a magnetic tape is housed in a case housing formed by combining an upper half and a lower half, and data is recorded on the magnetic tape. Are known. In particular, as a large-capacity recording medium for data backup in an external storage device such as a computer, a single tape reel wound with a magnetic tape is rotatably housed in a case housing composed of an upper half and a lower half. Are known.

As shown in an exploded perspective view in FIG. 3, a one-reel type magnetic tape cartridge of this type is composed of an upper half 30 and a lower half 32 combined with four case fixing screws 34 arranged at four corners. A single tape reel 38 around which the magnetic tape 36 is wound is rotatably housed in the case housing.

The tape reel 38 is formed by connecting an upper flange 40 and a lower flange 42 formed in a disk shape via a winding shaft 44, and is integrally provided at the center of the lower flange 42. The magnetic tape 36
Are wound, and various types of analog or digital data are recorded on the magnetic tape 36.

[0005] The tape reel 38 is provided with a rotation lock mechanism to prevent rattling when the magnetic tape cartridge is carried. The rotation lock mechanism includes a gear 40 engraved on the outer periphery of the upper flange 40.
a, and lock members 58, 58 urged by a spring toward the gear 40a. The lock members 58, 58 act as described below when the magnetic tape cartridge is removed from the recording / reproducing apparatus. It is configured.

That is, the winding shaft 44 of the tape reel 38
A bearing 47 is fitted therein, and a rotation support member 46 is further fitted to the bearing 47.
A compression coil spring 48 for urging the reel is mounted on the rotation supporting member 46. Then, the compression coil spring 48 is supported by the inner surface of the upper half 30 and the tape reel 38 is pressed downward, whereby the tape reel 38 is pressed.
Is normally urged downward toward the lower half 32,
The rotation of the above-mentioned tape reel is locked.

As will be described later, when the magnetic tape cartridge is loaded in the recording / reproducing apparatus, the lower half 32
A drive shaft (not shown) of the recording / reproducing apparatus acts to push up the tape reel 38 upward through a circular opening 50 opening at the center of the bottom surface of the recording medium. Since the urging is released, the above-described rotation lock of the tape reel is released, and the tape reel 38 can be rotated stably, thereby enabling good recording and reproduction.

The lower half 32 includes a magnetic tape 36.
A tape drawer 54 (lower half thereof) for pulling out the magnetic tape 36 from the case housing when the magnetic tape 36 is loaded into a recording / reproducing apparatus for recording or reproducing data on the tape.
When the magnetic tape cartridge is removed from the recording / reproducing apparatus, the door 5 for closing the tape outlet 54.
2 are installed. At the end of the magnetic tape 36, a leader tape 56 for pulling out the magnetic tape 36 from the magnetic tape cartridge when mounted on the recording / reproducing apparatus is mounted.

[0009]

Here, a coil spring 48 for urging the tape reel 38 downward toward the lower half 32 at all times is a rotation supporting member when assembling the magnetic tape cartridge. Since it is assembled by placing it on 46 and covering the upper half 30,
It must be able to be stably mounted on the rotation support member 46.

For this reason, conventionally, as shown in FIG.
2 is provided, and the end face of the closely wound portion 72 is ground.
Both ends were final end turns 74 orthogonal to the center line of the spring. However, the compression coil spring 70 configured as described above requires both ends to be ground, which has been one of the causes that the manufacturing cost cannot be reduced.

The above-mentioned tightly wound portion usually refers to a winding portion provided at the end of the coil spring and having an interval substantially equal to 0, and the final end winding portion is generally referred to as an end portion of the coil spring. , A winding portion constituting an end face.

Conventionally, the above problem can be dealt with by this method if the terminal end of the coil spring can be wound inside the coil. However,
Such a system (structure) cannot be adopted as a compression coil spring for use in a magnetic tape cartridge as described above because a rotation support member is fitted in the coil.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and has as its object to provide a terminal that can be manufactured at low cost and can be stably mounted on a target member. It is an object of the present invention to provide a coil spring for use when the part cannot be wound inside.

[0014]

In order to achieve the above-mentioned object, a coil spring according to the present invention is a compression coil spring for use when the terminal end cannot be wound inside, and the compression coil spring is used. No grinding is performed on the end of the coil, and the end face has at least one half turn of the coil at right angles to the center line of the spring.

In the magnetic tape cartridge using the coil spring according to the present invention, a magnetic tape is rotatably housed in a case housing composed of a combination of an upper half and a lower half, and data is stored on the magnetic tape. A magnetic tape cartridge for recording, comprising a tape reel for winding and holding the magnetic tape, a rotatable support for the tape reel, and a drive shaft for driving the tape reel at a center position of the tape reel. The lower half in which a circular opening to be inserted is formed, a compression coil spring for urging the magnetic tape toward the lower half, and supporting the compression coil spring, in combination with the lower half, A case housing, and the upper half for storing a tape reel holding the magnetic tape in the case housing; It has the compression coil spring,
The compression coil spring is characterized in that the end portion is not ground and the end face has a final end turn portion that is orthogonal to the center line of the spring at least half of the coil. .

Here, the above-mentioned coil spring (compression coil spring) is configured such that the final end turn portion orthogonal to the center line of the spring provided at the end of the spring is formed by a half turn to a three-quarter turn of the coil.
It is preferable to have a configuration having winding.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A coil spring according to the present invention will be described below with reference to the accompanying drawings, taking a magnetic tape cartridge as a preferred application form as an example.

FIG. 1 shows a compression coil spring for urging a reel in a magnetic tape cartridge using a coil spring according to an embodiment of the present invention, which constantly urges a tape reel downward toward a lower half. FIG. 2 is a front view, and FIG. 2 is a developed view for explaining the structure of the compression coil spring, that is, the state of setting the bending angle in the axial direction of the winding wire.

As shown in FIGS. 1 and 2, a compression coil spring for biasing a reel used in a magnetic tape cartridge according to the present invention is provided at both ends 1 of a compression coil spring 10.
2 has a shape in which the final end winding portion 14 provided on the coil 2 is wound so that only one half to three quarters of the coil is flat so as to be orthogonal to the center line of the spring. A coil rising portion 16 is provided following the final end winding portion 14, and the coil portion 18 follows.

Here, when the number of turns of the final end winding portion 14 at both ends 12 is equal to or less than one half of the coil, the compression coil spring 10 becomes unstable when placed upright, and becomes If more than three turns, the rising part 1 of the coil
In the case of No. 6, since it is necessary to start up to a height exceeding the wire diameter with the remaining one-quarter turn, designing becomes difficult when the wire diameter is large. Therefore, the rising portion 16
It is preferable that the number of windings is equal to or more than 1/2 turn and not more than 3/4 turn of the coil.

As described above, the rising portion 16 of the coil is formed as a final end winding portion 14 during a period from one-half turn to three-quarters turn of the coil until the first turn. This is a portion for rising up to the height of the wire diameter of the coil, and there is no limitation on the number of turns. In the present embodiment, the rising portion 16 has one turn, and the final end winding portion 14 and the rising portion 16 and a compression coil spring 1
The both ends 12 of 0 are 1 turn and 3/4. The coil portion 18 is a main portion acting as a spring of the compression coil spring 10, and the wire diameter, the outer diameter, the pitch, and the like of the coil are determined by ordinary calculation of the spring.

According to the above embodiment, there is an effect that a compression coil spring for use when the terminal end cannot be wound inside can be manufactured at low cost. Needless to say, this compression coil spring has a characteristic that it can be stably mounted on a shaft-like target member.

The above embodiment is merely an example of the present invention, and the present invention is not limited to the embodiment. Appropriate changes or improvements may be made without departing from the spirit of the present invention. Needless to say, this may be done.

[0024]

As described above, the compression coil spring for biasing the reel according to the present invention, which can be suitably used for a magnetic tape cartridge or the like, is manufactured by grinding both ends when manufacturing the coil spring. There is an effect that it can be manufactured at low cost because there is no such material. Also, when assembling the magnetic tape cartridge, it can be stably mounted on the rotating support member, so it can be handled just like a conventional compression coil spring with both end faces ground. This has a great effect on the cost reduction of the magnetic tape cartridge.

[Brief description of the drawings]

FIG. 1 is a front view showing a compression coil spring used in a magnetic tape cartridge according to an embodiment of the present invention.

FIG. 2 is a development view of the compression coil spring shown in FIG.

FIG. 3 is an exploded perspective view showing a one-reel type magnetic tape cartridge according to the related art.

FIG. 4 is a front view showing a compression coil spring according to the related art.

DESCRIPTION OF SYMBOLS 10, 48 Compression coil spring 12 Both end portions 14 Final end winding portion 16 Rising portion 18 Coil portion 30 Upper half 32 Lower half 38 Tape reel 46 Rotation support member

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Shozo Omori 2-12-1 Ogimachi, Odawara-shi, Kanagawa F-Term in Fuji Photo Film Co., Ltd. 3J059 AD05 BA01 BD01 CA01 CC10 GA25

Claims (1)

[Claims] 1. A compression coil spring to be used when its end cannot be wound inside, wherein the compression coil spring is not ground at its end, and
A coil spring, comprising, on an end face, a final end turn portion orthogonal to a center line of the spring, the half turn or more of a coil.