JP2536810Y2 - Tape cassette - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a tape cassette in which a tape runs between a pair of reels, and more particularly, to a guide pin for changing a running direction of the tape.

[Summary of Invention] In the present invention, in a tape cassette provided with a guide pin for changing the running direction of the tape and press-fitting the guide pin into a case, the press-fit portion of the guide pin is formed in a tapered shape having a small diameter at the tip. By doing so, the removal force of the guide pin is improved, and the flatness of the case is likely to be maintained.

2. Description of the Related Art A tape cassette having a high track density has been proposed as an external recording device of a computer (US Pat. No. 4,198,01).
No. 3).

In this tape cassette, a supply reel and a take-up reel are rotatably supported in a case, and a tape running path for running the tape wound therearound is provided between the supply reel and the take-up reel. I have. The tape running path is configured by winding a tape at a predetermined angle and arranging guide pins for changing the running direction of the tape at predetermined positions. Sixth
As shown in the figure, the guide pin 9 is attached to a tape winding portion 9a.
And a press-fit portion 9c located below the upper and lower flange portions 9b and a lower end flange portion 9b. The tape winding portion 9a, the flange portion 9b, and the press-fit portion 9c each have a fixed diameter. Formed. The guide pin 9 is fixed to the case by press-fitting the press-fitting portion 9c of the guide pin 9 into the aluminum case lower case portion 3 of the case.

[Problem to be Solved by the Invention] However, since the guide pin 9 is an integral member, the guide pin 9 is generally processed by cutting, and the tape winding portion 9a and the flange portion 9b are formed.
And a press-fit portion 9c. Therefore, the dimensions of each part may not be accurately formed due to conditions such as wear of the cam of the lathe, biting of the cutting tool, cutting oil, and the like. For example, as shown in FIG. In some cases, it is formed in a reverse tapered shape (a <b) in which the diameter gradually increases toward. When the press-fitting portion 9c having the reverse tapered shape is pressed into the lower case portion 3, the lower case portion 3
The hole 33 formed at the front end of the maximum diameter of the press-fitting portion 9c is widened over the entire range. Therefore, the force with which the lower case portion 3 presses the press-fit portion 9c after the press-fitting decreases as the distance from the tip to the flange portion 9b side decreases, so that the force (removal force) required to remove the guide pin 9 from the lower case portion 3 is reduced. There is a drawback that the guide pin 9 is weak and may come off due to external force such as vibration.

Further, the impact of the lower case portion 3 at the time of press-fitting when the guide pin 9 is press-fitted is maximum at the beginning of press-fitting, but the impact on the lower case portion 3 becomes extremely large since the tip of the press-fitting portion 9 has the maximum diameter. And the lower case part 3 is deformed by this impact,
There is a disadvantage that the flatness of the lower case part 3 may not be maintained. If the flatness of the lower case portion 3 is not maintained, inconveniences such as unstable tape running will occur.

In addition, the above-mentioned disadvantage may cause a small possibility even when the press-fitting portion 9c is formed in a straight shape instead of an inverted taper shape.

Accordingly, an object of the present invention is to provide a tape cassette which has a high possibility that the removal of the guide pins is improved and the flatness of the case is maintained.

Means for Solving the Problems In order to achieve the above object, a tape cassette of the present invention is provided with a supply reel and a take-up reel rotatable on a metal lower case portion, and the supply reel and the take-up reel are provided. A tape running path on which the tape wound around the supply reel and the take-up reel runs is provided between the reel and the reel, and a guide pin for changing the running direction of the tape is arranged at a predetermined position on the tape running path. Then, in a tape cassette in which the guide pins are pressed into the lower case and supported, such that the press-fit portion of the guide pin becomes smaller in diameter toward the press-fitting tip.
When the entire press-fitting portion is formed in a tapered shape, and the degree of the taper is A, the diameter of the upper position is B, the diameter of the lower position is B, and the height between the upper position and the lower position is l, (A− B) It is set so that the value of / l becomes a value of 1/250 to 1/38.

[Operation] When the press-fit portion of the guide pin is press-fitted into the lower case portion, the impact at the beginning of press-fitting into the lower case portion is minimized because the tip of the press-fit portion has a minimum diameter. Also, in this press-fitting process, since the hole formed in the lower case portion is gradually expanded each time the press-fitting stroke becomes deeper, the force of the lower case portion pressing the press-fit portion after press-fitting is applied to the entire pressing surface of the press-fit portion. Over the predetermined pressure.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First
5 to 5 show one embodiment of the present invention.

3 and 4, the case 1 comprises an upper case part 2 made of plastic and a lower case part 3 made of aluminum alloy, and the lower surface of the side wall part 4 provided on the periphery of the upper case part 2 is lower. It is butted against the periphery of the case part 3. A supply reel 5 and a take-up reel 6 are rotatably provided in the case 1. The supply reel 5 and the take-up reel 6
A tape running path 8 for running the tape 7 is formed between the two. The tape 7 is wound around the take-up reel 6 after one end is wound around the supply reel 5 and the other end is run on the tape running path 8. This tape running path 8 has two flanged guide pins near the front of the case 1.
Straight guide pins 11, 12, 13 are provided between the supply reel 5 and the guide pin 9, between the guide pin 9 and the guide pin 10, and between the guide pin 10 and the take-up reel 6, respectively.
Are provided upright on the lower case portion 2. That is, the tape 7 guided from the supply reel 5 is wound around the guide pin 9 by a predetermined angle, is changed in direction, and runs near the front surface of the case 1 in parallel with the front surface. Then, it is wound around the guide pin 10 by a predetermined angle, is changed direction again, and is guided to the take-up reel 6.

As shown in detail in FIG. 1 (a), the flanged guide pins 9, 10 are provided with tape winding portions 9a, 10a, flange portions 9b, 10b at upper and lower ends of the tape winding portions 9a, 10a and flanges at lower ends. And press-fit portions 9c and 10c located below the portions 9b and 10b, and are integrally formed by cutting from a non-magnetic stainless material. The tape 7 is wound around the tape winding portions 9a and 10a at a predetermined angle, and the upper and lower flange portions 9b and 10b regulate the displacement of the tape 7 in the width direction. The press-fit sections 9c and 10c are shown in FIG.
As shown in FIG. 1 (a), it is formed in a tapered shape (positive tapered shape) which gradually becomes smaller in diameter toward the press-fitting tip, as shown in FIG. 1 (a).
When the diameter at the upper position is A, the diameter at the lower position is B, and the height between the upper and lower positions is 1, the value of (AB) / l is
It is set to be in the range of 1/250 to 1/38. Here, if the taper amount is larger than this value, the likelihood that the flatness of the lower case portion 3 will be maintained is reduced due to stress at the time of press-fitting. May have an inversely tapered shape.

As shown in detail in FIG. 2 (a), the straight guide pins 11, 12, 13 are formed integrally with a tape contact portion 11a, 12a, 13a and a press-fit portion 11b, 12b, 13b located below the tape contact portion. It is formed integrally by cutting from a non-magnetic stainless steel material. The press-fit portions 11b, 12b, 13b are also formed in a tapered shape in the same range as described above. Also, of the straight guide pins 11, 12 and 13, 11 and 13 which come into contact with the magnetic surface of the tape 7 will be described.
Has a surface roughness Rmax in the range of 0.1 to 0.4 μm. The surface roughness of the conventional guide pin was formed to Rmax 0.5 to 0.8 μm, and the amount of powder falling was poor in durability and reliability.However, if the surface roughness was set as in this embodiment, As a result, the amount of powder falling is small and the durability and reliability are improved. Comparing the conventional and the present embodiment with the number of hard errors with respect to the number of times of tape running, experimental data as shown in FIG. 5 was obtained. Also, set the surface roughness to Rmax0.1
In order to stably work in the range of 0.4 to 0.4, it is preferable to perform SF treatment (super finish treatment) after centerless polishing. When the surface roughness is set to Rmax 0.1 μm or less,
The sticking phenomenon of the tape 7 occurs, which is not preferable.

The guide pins 9 to 13 configured as described above are inserted into holes 32 formed in the lower case portion 3 as shown in FIG.
Further, as shown in FIG. 2 (a), it is press-fitted into the lower case portion 3 where no hole is formed, and FIG. 1 (b) and FIG. 2 (b).
It is fixed as shown. The press-fitting method may be either a method in which a hole is formed in the lower case portion 3 or a method in which no hole is formed in advance, and is appropriately determined based on the diameter of the press-fit portion, the shearing force of the lower case portion 3, and the like.

In this press-fitting process, a hole formed in the lower case portion 3
Since the press-fitting portions 9a to 13a are formed in a positive taper shape, the press-fitting 32 is gradually expanded on all the press-contact surfaces every time the press-fitting stroke becomes deeper, and the press-fitting is completed. Therefore, the force with which the lower case part 3 presses the press-fitting parts 9a to 13a after press-fitting becomes equal to or higher than a predetermined pressure over the entire press-contact surfaces of the press-fitting parts 9a to 13a, and the guide pins 9 to 13
It is fixed in a state where the force required to pull out (extraction force) is strong. In addition, at the beginning of the press-fitting when the largest impact is applied to the lower case portion 3, since the tips of the press-fitting portions 9a to 13a have the minimum diameter, they are pressed down to the minimum. Therefore, there is little possibility that the lower case portion 3 is deformed by the impact at the beginning of the press-fitting, and the flatness of the lower case portion 3 is likely to be maintained.

The tape running path 8 is provided with a tape exposed portion 20 for exposing a part of the running tape 7 to the outside of the case 1. The tape exposed portion 20 is a portion where the tape 7 is pressed against the head when the drive device is mounted.
Is opened and closed by a cover 23. This cover 23 has a notch 21
Has a shape that covers the space formed by
It is rotatably supported by 30 and is urged to the closed position by the spring force of the coil spring 31. Tape running drive mechanism
14 has a drive roller 15 at the front center in the case 1 and a pair of driven rollers 16 and 17 at the left and right corners at the rear. The drive roller 15 has a shaft 18 erected on the lower case 3.
The drive roller 15 and the shaft 18 are provided with grease for preventing wear. The upper portion of the drive roller 15 is formed in a large diameter portion 15a, and a part of the large diameter portion 15a is exposed to the outside of the case 1 through a hole 19 in the upper case portion 2. The pair of driven rollers 16 and 17 are also rotatably supported on shafts 18 and 18 erected on the lower case portion 3, respectively, so that a gap between the inner surface of each driven roller 16 and 17 and the outer surface of each shaft 18 and 18 is provided. Is provided with grease for tape resistance and the like.

An endless drive belt 25 is hung on the drive roller 15 and the pair of driven rollers 16,17. The drive belt 25 has flexibility, and a portion located between the drive roller 15 and each of the driven rollers 16 and 17 is pressed against the outermost periphery of the tape 7 wound around the supply reel 4 and the take-up reel 6. . In the figure, reference numeral 27 denotes a mirror for detecting a tape end.

 Hereinafter, the operation of the tape cassette will be described.

When the tape cassette is mounted on the drive device, the cover 23 rotates against the spring force of the coil spring 31 during the loading process. When the cover 23 is rotated to the release position, the head of the drive unit comes into pressure contact with the tape 7 located at the tape exposed portion 20, and the drive roller comes into contact with the rollers of the drive unit.
15 is pressed. When the drive roller 15 rotates by the rotation of the roller of the drive device, the driven rollers 16 and 17 also rotate, and the drive belt 25 travels in the direction of the arrow in FIG. When the drive belt 25 runs, the tape 7
A frictional force is received at a position where the pressure contact member 25 comes into contact with the recording head 25, and the recording / reproduction is performed by the head while traveling in the direction of the arrow in FIG.

[Effects of the Invention] As described above, according to the present invention, a guide pin for changing the running direction of the tape is provided, and in the tape cassette in which the guide pin is pressed into the lower case portion and supported, the press-fit portion of the guide pin is provided. Since the whole is formed in a tapered shape having a small diameter at the tip, there is an effect that the withdrawal force of the guide pin is improved and the possibility of maintaining the flatness of the lower case portion is also increased.

When the degree of taper is A at the upper position, B at the lower position, and 1 at the height between the upper and lower positions, the value of (A−B) / l is 1/250. Since it is set to be 1/38, the stress at the time of press-fitting is weakened, the flatness of the lower case part is likely to be maintained, and there is no possibility that it will have an inverse tapered shape due to variation in cutting. effective.

[Brief description of the drawings]

1 (a) to 5 show an embodiment of the present invention. FIG. 1 (a) is a sectional view showing a state before press-fitting a flanged guide pin, and FIG. 1 (b) is a sectional view showing a flanged guide pin. FIG. 2 (a) is a cross-sectional view showing a state before press-fitting a straight guide pin, FIG. 2 (b) is a cross-sectional view showing a state after press-fitting a straight guide pin, and FIG. FIG. 4 is an exploded perspective view of the tape cassette, FIG. 4 is a plan view of the tape cassette excluding the upper case portion, and FIG. 5 is a characteristic line diagram showing the number of hard errors with respect to the number of times of tape running. FIG. 6 shows a conventional example, FIG. 6 is a sectional view showing a state after press-fitting of a guide pin, and FIG. 7 is a partial front view of the guide pin. 1 ... case, 5 ... supply reel, 6 ... take-up reel,
7 Tape, 8 Tape running path, 9 to 13 Guide pins, 9c, 10c, 11b to 13b Press-fit portion.

Claims (1)

(57) [Scope of request for utility model registration] 1. A supply reel and a take-up reel are rotatably provided on a metal lower case portion, and a tape wound around the supply reel and the take-up reel is provided between the supply reel and the take-up reel. In a tape cassette in which a tape running path is provided, guide pins for changing the running direction of the tape are arranged at predetermined positions, and the guide pins are pressed into the lower case and supported. The entire press-fitting portion is formed in a tapered shape so that the press-fitting portion of the guide pin becomes smaller in diameter toward the press-fitting tip, and the degree of the taper is as follows: the diameter of the upper position is A, the diameter of the lower position is B,
When the height between the upper position and the lower position is l, (A−
B) A tape cassette wherein the value of / l is set to a value of 1/250 to 1/38.