JPS62219385A - Tape cartridge - Google Patents

Abstract

PURPOSE:To improve the performance of assembly by forming a flat surface as part of the internal surface of an upper case which is close to the pocket of a prism. CONSTITUTION:The flat surface 35 is formed as part of the internal surface 9a of the upper case 1a which is close to the pocket of the prism 22. Consequently, when the upper case, a window plate 14, and the prism 22 are molded in one body, a slide core is slidable on the flat surface 35 and they can be molded in one body. This integral molding uses a dichroic molding method wherein the upper case 1a is molded primarily and the prism 22 and window plate 14 are molded secondarily. The joined parts of the prism 22 and upper case 1a are fused mutually in the secondary molding, so they do not become flat and can not be used as a prism. For the purpose, the prism 22 is provided with a projection part 22c, which is used to join the prism 22 and upper case 1a with each other, thereby improving the reliability of the prism 22.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tape cartridge incorporating a prism used for optically detecting the beginning and end of a magnetic tape.

[Conventional technology]

Conventionally, tape cartridges incorporating this type of prism have been known, such as those shown in FIGS. 6 to 9 (for example, Japanese Utility Model Application No. 60-89678). There, a digital recording and reproducing type audio tape cartridge is shown, the main body case 1 of which is formed by abutting upper and lower plastic cases 1a and 1b and integrally connecting them with screws or the like. Hubs 4 , 4 are rotatably disposed on the left and right drive shaft insertion holes 3 , 3 opened in the bottom wall 2 inside the main body case 1 .
A magnetic tape 5 is connected to the magnetic tape 4 through a translucent adhesive tape and wound thereon.

On the front side of the main body case 1, tape outlet ports 6, 6 are formed on the left and right sides, and a pocket 7 for tape loading is formed between the tape outlet ports 6, 6, respectively. A guide member 8 is arranged.

The tape 5 is led out from one hub 4 through a tape outlet 6 in front of the hub 4 to a pocket 7 on the front of the case, and passes through the other tape outlet 6 to the other hub 4 located behind it.
It is wound up.

The tape loading pocket 7 is formed by recessing the tape into the case between the left and right tape outlet ports 6 and 6 of the lower case 1b. The front end is closed, but the front and lower surfaces are open. On the inner surface 9a of the upper wall 9 of the upper case 1a and the inner surface 2a of the bottom wall 2 of the lower case 1b, there are shielding walls 33a and 33b that partition the rear of the pocket 7 and the tape storage section, and on the left and right sides of the pocket 7, respectively. Shielding walls 34a and 34b are formed to partition the tape outlet 6, and these shielding walls 33a and 33b and the shielding walls 34a and 34b are butted against each other by butting the upper and lower cases 1a and 1b, respectively, and from the pocket 7. This prevents dust from entering the tape storage section and the tape outlet 6.

And, ・Front cover 1 for tape protection on the front of main case 1
0 closes the front opening of the pocket 7 and the front opening of the tape outlet 6 (when not in use).

It is pivotably mounted around a rotation shaft 11 in the upward open position (when in use).

Further, a shack 12 is provided on the outer surface side of the bottom wall 2 of the lower case 1b.
is attached so as to be slidable in the front-rear direction between a front pocket-closed position where the opening lower surface of the pocket 7 is closed and a rear pocket-opened position where the opening lower surface is opened.

A window hole 13 is opened in the upper wall 9 of the upper case 1a and extends approximately between the left and right sides of the rear half of the upper wall 9, and the window hole 13 is opened in the upper wall 9 of the upper wall 9, and extends approximately between the left and right sides of the rear half of the upper wall 9.
A transparent plastic window plate 14 is superimposed and fixed by ultrasonic welding or the like to close the window hole 13. The amount of tape wrapped around each hub 4 can be visually confirmed through this window plate 14.

A hub lock plate 15 is built into the main body case 1 to prevent the left and right hubs 4 from rotating when not in use. The hub lock plate 15 includes a left and right horizontally elongated horizontal plate part 15a, sliding leg parts 15b, 15b connected downwardly from the left and right ends of the horizontal plate part 15a, and integrated rearward from left and right rear ends of the horizontal plate part 15a. Protruding lock claws 16, 16. and a passive protrusion 17 protruding from the outer surface of the front end of the slide leg 15b. The hub lock plate 15 is mounted on the lower side of the left and right connecting arms 18 integrally projecting forward from the front end of the transparent window plate 14 so as to be movable back and forth. Then, in the lower case lb, the hub lock plate 1
5, a horizontal plate part 15a straddles the upper part of the tape 5 wound around the hubs 4 in the left and right direction, and the left and right slide legs 1
5b and 15b are assembled in the front position of the hubs 4 and 4 in the lower case 1b so that they are supported on the inner surface 2a of the bottom wall 2 of the lower case 1b. Thus, havelock plate 15
is movable in the front-rear direction between a locking position where the locking pawl 16 abuts and engages with the irregularities on the outer peripheral surface of the hub formed on the upper ends of the left and right hubs 4, and an unlocking position where the locking claw 16 is removed from the hubs 4. Therefore, the horizontal plate portion 33a and the shielding wall 3
3a, the hook is always pressed and biased toward the lock position by the spring member 21. That is, when not in use, the hub lock plate 15 engages the lock pawl 16 with the hub 4 to restrict rotation of the hub 4.

When loaded into the player, the front cover 10 is opened using the operating member on the player side.
swings upward, and the hub lock plate 15 is pulled forward to the unlocked position through abutting engagement with the passive protrusion 17 of the front lid 10 by this swinging upward.

The front end portions of the connecting arms 18, 18 project forward from the left and right front ends of the transparent window plate 14.

It extends to a rear position of the tape guide member 8 within the tape outlet 6 on the inner surface 9a of the upper wall 9 of the upper case 1a. An L-shaped prism 22 is integrally formed at the front end of the connecting arm 18.

The prism 22 is connected to the articulating arm 18 as shown in FIG.
It has a horizontal part 22a that is integrally molded directly on the front end of the horizontal part 22a in the left-right and inner-outside directions, and a vertical part 22b that is integrally molded in a form bent downward at right angles from the inner end of the horizontal part 22a in the left-right direction, The outer end surface in the left and right direction of the horizontal portion 22a is set as the incident-side transmission surface 23, the 45-degree inclined surface on the inner end side is set as the first reflective surface 24, and the 45-degree inclined surface on the inner end side of the vertical portion 22b is set as the second reflective surface. The reflection surface 25 has a vertical surface on the outer end side as an emission side transmission surface 26.
are set respectively. On the other hand, detection holes 29 and 30 are opened in the side walls 27 and 28 of the upper and lower cases 1a and 1b, respectively, and are arranged vertically so as to face the incident-side transmission surface 23 and the output-side transmission surface 26, respectively. The tape 5 passes between the emission side transmission surface 26 and the detection hole 30. The detection holes 29 and 30 are positioned so as to correspond to the light emitting element 31 and light receiving element 32 on the player side when the tape cartridge is loaded into the player.

Thus, when this tape cartridge is loaded into a player, the light emitted from the five light emitting elements 31 passes through the detection hole 29 on the tape cartridge side and reaches the incident side transmission surface 2 of the prism 22.
3. This incident light is transmitted to the first reflecting surface 24 and the second reflecting surface 24.
The direction of the light beam can be changed by 90 degrees with the reflective surface 25,
The light beam exits parallel to the incident light beam from the output-side transmission surface 26, passes through the tape 5, exits from the detection hole 30 to the outside of the case, and reaches the light-receiving element 32 on the player side, where the light intensity causes the magnetic tape 5 to or the transparent leader tape connected to this end, that is, the start or end of the magnetic tape 5 is detected.

Since the prism 22 has a very small shape compared to the entire tape cartridge, the upper case 1
It is very troublesome to assemble a into a predetermined position.

Regarding this point, in this conventional example, the prism 22 is integrally molded with the transparent window plate 14, so the prism 22 is assembled in a predetermined position at the same time as the window plate 14 is assembled, and the rim 22 is assembled. Easy to assemble with no hassle.

This conventional example also discloses that the transparent window plate 14 on which the prism 22 is integrally molded is integrally molded with the upper case 1a. According to this.

The assembling of the prism 22 and the window plate 14 to the main body case 1 can be completely omitted and the assembly process can be greatly simplified. Also, prism 22. If the window plate 14 and the main part of the upper case 1a are integrally molded, the prism 22 can be attached to the window plate 1.
In other words, if the prism 22 is integrally molded with only the window plate 14, the shape of the window plate 14 becomes complicated, and the window plate 14 is welded to the main body case 1. The assembling process becomes more troublesome, and the increased size of the window plate 14 makes it difficult to balance the welding with the upper case 1a, making it difficult to achieve welding accuracy, making it impossible to ensure the positional accuracy of the prism 22, resulting in variations in light detection accuracy. This is extremely advantageous because it can also solve the problem of easy occurrence of the problem.

[Problem that the invention seeks to solve]

However, in the conventional device described above, when the prism 22 is actually integrally molded into the upper case 1a, the following problems occur. That is, the prism 22 has the first reflective surface 24
Although it is shaped like this.

This first reflective surface 24 and the inner surface 9a of the upper wall 9 of the upper case 1a
This is because an underakasoto part is formed between the two.

For example, a slide core must be attached to the mold for molding. However, the inner surface 9 of the upper case 1a
At the location closer to the pocket 7 than the prism 22 in a,
A shielding wall 34a that partitions the pocket 7 and the tape outlet 6
is provided. Therefore, even if an attempt is made to use a slide core in the undercoat part, the shielding wall 34a
becomes an obstacle and makes its use impossible. This point is not necessarily clearly and specifically described in the specification, and such integral molding cannot actually be carried out based on this description.

This invention was made in view of this point.

It is an object of the present invention to provide a tape cartridge in which a prism can be easily and integrally formed at a predetermined position within a tape outlet of a main body case.

[Means for solving problems]

In order to achieve the above objectives, this invention.

Main case 1 formed by butting together upper and lower cases 1a and 1b
A tape outlet 6 and a tape loading pocket 7 are arranged side by side on the front side of the upper case 1 inside the tape outlet 6.
The present invention is based on a tape cartridge in which a prism 22 for detecting information is integrally molded on the inner surface 9a of the upper case 1a, and a portion of the prism 22 on the inner surface 9a of the upper case 1a near the center point 7 is formed into a flat surface 35. shall be.

Here, when integrally molding the prism 22 at a predetermined position on the inner surface 9a of the upper case 1a, it is necessary to integrally mold only the prism 22 to the upper case 1a using a two-color molding method, and to mold the prism 22 together with the window plate 14 on the upper case. Although it is optional to integrally mold the prism 22. Window board 14. The latter method, in which the king of the upper case 1a is integrally molded, is more advantageous than the former in that the number of assembly parts and assembly steps can be significantly reduced, and the positional accuracy of the prism 22 can be ensured. . In addition to detecting the beginning and end of the magnetic tape 5, the prism 22 is also used to detect information such as the type of magnetic tape 5, for example.

[Effect]

If the portion of the prism 22 near the pocket on the inner surface 9a of the upper case 1a is formed into a flat surface 35 as in the above configuration, the inner surface 9a of the upper case 1a and the first reflective surface 22 of the prism 22 are It is also possible to use a slide core even if there is an undercut between the two.

This allows for integral molding.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 5.

Overall configuration of tape cartridge and prism 22
Since the shape and mounting position of the prism are almost the same as those of the conventional one described above, the same reference numerals are given and the explanation thereof will be omitted. I will only explain the points.

In the main case 1, the shielding wall 34 that partitions the side of the pocket 7 and the tape outlet 6 is provided so as to protrude only from the lower case Ib side, and is not formed at all on the inner surface 9a of the upper wall 9 of the upper case 1a. , the corresponding portion of the upper case 1a is formed into a flat surface 35.

The upper end of the shielding wall 34 is brought into contact with the flat surface 35 to prevent dust from entering the tape outlet 6 from the pocket 7, thereby eliminating dust from adhering to the tape 5 and the prism 22.

In this way, the prism 2 on the inner surface 9a of the upper case 1a
2 is formed on the flat surface 35, so that the upper case 1a, the window plate 14, and the prism 22
When integrally molding the champion, the slide core can be made slidable on the flat surface 35, making it possible to integrally mold the slide core. This integral molding is performed by primary molding the upper case 1a.

A two-color molding method is used in which the prism 22 and the window plate 14 are secondary molded. During this two-color molding, the joint portion between the prism 22 and the upper case 1a is welded to each other as shown in FIG. 1, so it does not become a flat surface and cannot be used as a prism. Therefore.

The reliability of the prism 22 is improved by providing a protrusion 22c on the prism 22 and joining the prism 22 and the upper case 1a with the protrusion 22C.

FIGS. 3 to 5 show a core bank type mold structure for the prism portion of the upper case 1a.

In the primary molding of the upper case 1a, the left and right slide cores 36 and 3 are used to form the undercarriage portions of the left and right prisms.
7 is pushed by the advancement of the central slide core 38 in the direction of arrow C, which intervenes in the middle.

The slide cores 36 and 37 and the core block 39 abut against each other on seven sides, preventing resin from flowing into the prism section. In the secondary forming of the prism 22 and the window plate 14, the core block 39 is moved back by a predetermined amount and stopped at position B, and the seal of the prism portion A is opened by this moving back, thereby making it possible to perform the secondary forming. Next, when the mold is opened, the central slide core 38 retreats in the direction of arrow C' in FIG. 3, the left and right slide cores 36 and 37 return to the center, and the undercut forming the prism portion A is removed. It becomes possible to eject. Incidentally,
The end surface 22d of the protrusion 22C of the prism 22 shown in FIG. 1 corresponds to the seven abutting surfaces of the mold shown in FIG. 4. Note that in FIGS. 4 and 5, numerals 40 and 41 indicate an upper mold and a lower mold for molding the upper case 1a, which is the primary molding.

〔Effect of the invention〕

As explained above, according to the present invention, the upper case 1a
By simply forming the pocket-proximity portion of the prism 22 on the inner surface of the prism 22 into a flat surface 35, the prism 2
2 in the tape outlet 6, the prism 2
The prism 22 can be integrally molded into the upper case 1a, which reduces the number of parts and man-hours required for assembly compared to a structure in which the prism 22 is configured separately from the upper case 1a. You can improve.

[Brief explanation of drawings]

1 to 5 show an embodiment of the present invention,
FIG. 1 is a sectional view of the main parts of the tape cartridge, and FIG. 2 is a plan view showing the inner surface of the upper case. Fig. 3 is a plan view showing the mold configuration of the prism part of the tape cartridge, Fig. 4 is a sectional view taken along the line ■-■ in Fig. 3,
FIG. 5 is a sectional view taken along the line V-V in FIG. 3. 6 to 9 show conventional tape cartridges, FIG. 6 is an external perspective view of the tape cartridge viewed from above, FIG. 7 is an external perspective view of the tape cartridge viewed from the bottom, and FIG. 8 is an external perspective view of the tape cartridge viewed from the bottom. 9 is an internal plan view of the upper case shown in an assembled state, and FIG. 9 is a sectional view taken along the line IX-IX in FIG. 8. 1... Main body case. 1a... Upper case. ■b...Lower case. 4...Hub. 5...Tape. 6...Tape outlet. 7. Pocket for tape loading. 14...Window board. 22... ・Prism. 34... Shielding wall. 35...Flat surface. Inventor Shudo Yamamoto
Corner 1) Takashi Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] (1) A tape outlet 6 and a pocket 7 for tape loading are provided side by side on the front side of the main case 1, which is formed by butting together the upper and lower cases 1a and 1b, and the inner surface 9a of the upper case 1a inside the tape outlet 6 is used for information detection. A tape cartridge characterized in that a prism 22 is integrally molded, and a portion of the inner surface 9a closer to the pocket 7 than the prism 22 is formed as a flat surface 35.