JPS6325575Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement of a magnetic tape cartridge, and its purpose is to prevent bending deformation of the front central portion of the main body case made of plastic.

Conventionally, ultra-small magnetic tape cartridges, so-called microcassettes, have lacked strength in some areas due to their miniaturization. In other words, although the main case, which is made up of upper and lower plastic cases joined together in a lid-like manner, has many insertion windows for magnetic heads and the like on the front, there are no connections between the upper and lower cases from the inner surfaces of the upper and lower cases at the middle part in the left and right direction. There are few wall members that stick together. Therefore, the center part in the left-right direction of the main body case, especially the front part, is likely to bend and deform in the vertical direction. This bending deformation causes the magnetic tape running on the inside front of the main body case to shift upward or downward, causing head azimuth to be distorted, making it difficult to produce high-pitched sounds, or causing the level to suddenly drop and become unclear during playback. This resulted in disadvantages such as:

This idea focuses on this fact, and by providing a reinforcing rib in the front central part of the main body case,
An object of the present invention is to provide a magnetic tape cartridge that can prevent bending deformation of the front central portion of the main body.

The details will be explained below based on the drawings. The drawing shows an example of an ultra-small magnetic tape cartridge, a so-called microcassette.

In FIG. 1 and FIG. 2, 1 is a main body case. This is plastic upper and lower case 1
a, 1b are fitted together and connected at their four corners with tapping screws 2, and drive shaft insertion holes 3, 3 are formed vertically through the center on the left and right sides. Inside the main body case 1, a pair of left and right hubs 5, 5 on which magnetic tape 4 is wound are rotatably installed above each drive shaft insertion hole, and guide rollers 6, 6 are rotatably installed at the front left and right corners. It is located in

On the front surface of the main body case 1, a pinch roller insertion window 7 is opened at the center in the left and right direction, and a magnetic head insertion window 8 is opened at a position symmetrical to the insertion window 7.
8 and erase head insertion windows 9, 9, respectively.
A capstan shaft insertion hole 10 is provided vertically through the rear portion of the pinch roller insertion window 7, and positioning pin insertion holes 11 are provided vertically through the rear portions of each erasing head insertion window 9. . Then, the pinch roller insertion window 7 and each magnetic head insertion window 8, 8
A total of four tape guide pins 12, 12 and 13, 13 are provided between each magnetic head insertion window 8, 8 and each erase head insertion window 9, 9.
It is erected from the lower case 1b. Further, a pad 14 is supported by a leaf spring 15 at the rear portion of each magnetic head insertion window 8, 8.

In this case, the magnetic tape 4 fed out from one hub 5 is guided by both tape guide rollers 6, 6, and even if the main body case 1 is used inverted, it is always pinched by the erasing head insertion part 9 and the magnetic head insertion window 8. It passes through the roller insertion window 7 in order and is wound up on the other hub 5. At that time, when the erase head, magnetic head, and pinch roller on the tape recorder side are inserted into the insertion windows 9, 8, and 7 on the main body case 1 side on the tape running path inside the front surface of the case 1, the magnetic tape 4 Tape guide pin 1 mentioned above
At steps 2 and 13, movement to the rear within the case is restricted and travel guidance is provided.

Now, in the magnetic tape cartridge having such a structure, this invention is characterized in that reinforcing ribs 16, 16 and 17, 17 are provided at the front inside the main body case 1.

As one specific example, detailed views are shown in FIGS. 4 to 7. On the lower case 1b side,
As shown in FIGS. 4 and 5, a pair of parallel reinforcing ribs 16, 16 extend straight rearward from the left and right sides of the capstan shaft insertion hole 10 located behind the pinch roller insertion window 7, respectively. are provided protruding to a height approximately equal to the depth of the lower case 1b, and on the other hand, on the upper case 1a side, as shown in FIGS. 6 and 7, are provided at symmetrical positions behind the capstan shaft insertion hole 10. A pair of parallel reinforcing ribs 1 long in the front and back direction
7 and 17 are provided to protrude higher than the depth of the upper case 1a. These reinforcing ribs 16, 16 and 17,
17 is a pair of reinforcing ribs 17 on the lower case 1b side between the tips of the pair of reinforcing ribs 17 on the upper case 1a side as shown in FIGS. 4 and 8 when the upper and lower cases 1a and 1b are put together. The reinforcing ribs 16, 16 fit together, and in FIG. 8, the right side surface 17a of the left side reinforcing rib 17 on the upper case 1a side and the left side surface 17b of the right side reinforcing rib 17, and the left side surface of the left side reinforcing rib 16 on the lower case 1b side. 16a and the right side surface 16b of the right reinforcing rib 16 are provided in a positional relationship that closely opposes each other. In other words, these reinforcing ribs 16, 16 and 17, 17 are set in a positional relationship such that a pair of reinforcing ribs 17, 17 on the upper case 1a side sandwich a pair of reinforcing ribs 16, 16 on the lower case 1b side. There is.

In this way, reinforcing ribs 17 and 1 are provided at the front center of each of the upper case 1a and the lower case 1b of the main body case 1.
When 7 and 16, 16 are respectively protruded,
Even if a vertical bending force is applied to the front part of the center part in the left-right direction of the main body case 1, the reinforcing ribs 17, 17 and 16, 16 can sufficiently resist the bending force, and the bending deformation of that part can be prevented.

In the examples shown in FIGS. 4 to 7, in order to further enhance the reinforcing function, the rear ends of the pair of reinforcing ribs 16, 16 on the lower case 1b side are connected by a connecting rib 18.
The rear ends of the pair of reinforcing ribs 17, 17 on the upper case 1a side are each integrally connected by a connecting rib 19.

The connecting rib 18 on the lower case 1b side is connected to the lower case 1
b From the butt pin 20 protruding from the center rear part of the capstan shaft insertion hole 10 on the inner surface to the left and right tape guide pins 12 of the capstan shaft insertion hole 10,
12 adjacent parts, each of the left and right hubs 5, 5
It is provided in a planar mountain shape to protrude along the outer periphery of the maximum winding diameter of the magnetic tape 4 when the magnetic tape 4 is fully wound. Connecting rib 19 on the upper case 1a side
is the capstan shaft insertion hole 1 on the inner surface of the upper case 1a.
A butt pin 21 is provided at the center of the central rear portion of the case 0 in a butting manner to butt with the butt pin 20, and is provided so as to protrude vertically symmetrically with the connecting rib 18 on the lower case 1b side. ing. Each of the connecting ribs 18 and 19 is kept at a height approximately equal to the respective depths of the lower case 1b and the upper case 1a.

9 to 12 show another specific example, in which a pair of reinforcing ribs 16, 16 on the lower case 1b side are provided to protrude higher than the depth of the lower case 1b, and this rib 16 , 16 are held between a pair of reinforcing ribs 17, 17 on the upper case 1a side. The front ends of the pair of reinforcing ribs 16, 16 on the lower case 1b side are connected to hole edge ribs 22 that protrude along the edge of the capstan shaft insertion hole 10.
The rear ends are connected together by connecting ribs 18 which are mountain-shaped in plan view, as in the above embodiment.

FIGS. 13 to 16 show yet another specific example, in which a pair of reinforcing ribs 16, 16 on the lower case 1b side are protruded to approximately the same height as the depth of the lower case 1b, The front ends of the ribs 16, 16 are integrally connected by a supplementary rib 23 extending in the left-right direction from a hole edge rib 22 protruding along the edge of the capstan shaft insertion hole 10, and the rear ends are connected together. A reinforcing rib 1 is integrally connected by a connecting rib 18 as in the above embodiment, and the ribs 16, 16 protrude higher than the depth of the upper case 1a on the upper case 1a side.
The tips of numbers 7 and 17 are held in place.

Note that this invention is also effective when applied to a normal Philips type magnetic tape cartridge. In this case, a magnetic head insertion window is opened in the center of the front side of the main body case in the left and right direction, and the magnetic head can be inserted. Spare insertion windows are formed on the left and right sides of the window, and pinch roller insertion windows and erasing head insertion windows are formed symmetrically on the left and right outside of the preliminary insertion windows, so that the rear part of the magnetic head insertion window The reinforcing ribs 16, 16 and 17, 17 are provided so as to be located at.

In summary, this invention consists of a pair of left and right reinforcing ribs 17, 17 and 16, 1 that are long in the front and back direction at the rear part of the insertion window for a pinch roller, etc., which opens at the center in the left and right direction of the front surface of the main body case 1 made of plastic.
6 are provided protruding from the upper and lower cases 1a and 1b, respectively, and the upper case 1a or the lower case 1b
Since a pair of reinforcing ribs protruding from one side of the main body case 1 sandwich a pair of reinforcing ribs protruding from the other side, vertical bending deformation of the central front part of the main body case 1 can be prevented. Therefore, the upward or downward deviation of the magnetic tape 4 caused by the bending of that portion is eliminated, and there is an advantage that the magnetic tape 4 can always run normally on the inside of the front surface.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway overall plan view of the magnetic tape cartridge according to this invention, Fig. 2 is a front view of the front center portion thereof, and Fig. 3 is a plane showing the inner shape of the upper case constituting the main case. Figure 4 is an enlarged plan view of the main parts of the lower case, Figure 5 is its front view, and Figure 6 is an enlarged plan view of the main parts of the lower case.
7 is an enlarged plan view of the main part of the upper case, FIG. 7 is a front view thereof, and FIG. 8 is a diagram showing the combination of reinforcing ribs of the upper and lower cases, taken along the line A--A in FIG. 4. FIG. 9 is an enlarged plan view of the main parts showing another modification of the lower case, FIG. 10 is a front view thereof, and FIG.
Figure 1 is an enlarged plan view of the main parts of another modified example of the upper case used in combination with the lower case.
Figure 2 is its front view. FIG. 13 is an enlarged plan view of the main part showing still another modification of the lower case, the first
FIG. 4 is a front view thereof, FIG. 15 is an enlarged plan view of a main part showing still another modification of the upper case used in combination with the lower case, and FIG. 16 is a front view thereof. 1...Main case, 1a...Upper case, 1b...
...Lower case, 4...Magnetic tape, 5...Hub, 7
... Pinch roller insertion hole, 8 ... Magnetic head insertion window, 9 ... Erasing head insertion window, 10 ... Capstan shaft insertion hole, 16 ... Reinforcement rib on the lower case side,
17...Reinforcement rib on the upper case side.

Claims (1)

[Scope of utility model registration request] The inside of the main case 1, which is formed by joining upper and lower plastic cases 1a and 1b in a lid-like manner, has hubs 5, 5 around which magnetic tape 4 is wound on the left and right sides, and a pinch roller on the tape recorder side is mounted on the front of the main case 1. , the insertion windows into which the magnetic head and erasing head are inserted are opened in parallel in the left and right direction, and the magnetic tape 4 is fed out from one hub 5, passes through the inside front of the main body case 1, and is wound onto the other hub 5. In case of magnetic tape cartridge, main body case 1
A pair of left and right reinforcing ribs 17, 17 and 16, 16, which are long in the front and back direction, are provided at the rear part of the insertion window located at the center in the left and right direction of the front surface of the upper and lower cases 1a,
1b, and protruding from either the upper case 1a or the lower case 1b.
A magnetic tape cartridge characterized in that a pair of reinforcing ribs is arranged in such a manner as to sandwich a pair of reinforcing ribs protruding from the other.