JPH04188483A - Tape cartridge - Google Patents

Abstract

PURPOSE:To enhance a positional accuracy and to stabilize a tape traveling operation by a method wherein tape guide pins are erected and installed collectively high from a lower-half case and the diameter size of side tape guide pins is set to be larger than the thickness size of ribs at the lower-half case. CONSTITUTION:Central tape guide pins 15, 15 are erected and installed to be collectively high from a lower-half case 1b at the front right and the front left of a recording and replay head insertion window 7; side tape guide pins 16, 16 are erected and installed to be collectively high from the lower-half case 1b at the front right and the front left of an erasure head insertion window 8 and a pin roller insertion window 9. The individual side tape guide pins 16 and partition walls 5 are erected and installed collectively high from the lower- half case 1b and are connected serially by using ribs 25 which are lower than the pins 16. In this case, the diameter size of the individual side tape guide pins 16 is nearly the same as the diameter size of the central tape guide pins 15 and is set to be larger than the thickness size of the ribs 25. Thereby, it is possible to mold a tape cartridge with high accuracy without causing a retreat.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a Phillips-type tape cartridge, in which the tape guide portion on the front surface of the main body case is improved.

(Prior Art) As shown in the attached drawing, this type of Phillips-type tape cartridge consists of a plastic upper and lower half case 1a.
-A partition wall 5 is provided along the tape running path P on the front surface of the main case 1, which is formed by joining the main case 1b together in a lid-to-bottom manner. The basic configuration is such that a recording/reproducing head insertion window 7 is formed in the center, and an erasing head insertion window 8 and a pinch roller insertion window 9 are formed at left-right symmetrical positions.

Central tape guide pins 15 are integrally erected high from the lower half case 1b on the front left and right sides of the recording/reproducing head insertion window 7, and on the front left and right sides of the erasing head insertion window 8 and the pinch roller insertion window 9, respectively. Ribs 25, 25 extend forward from the partition wall 5, and guide the tape 2 at a total of six locations, including the central tape guide pin 15 and the front ends of the ribs 25.

In this case, it is also known, for example, from Japanese Utility Model Application No. 62-151.75, that the ribs 25 and the central tape guide pin 15 are gathered together on the lower half case Ib side and erected high.

[Problem to be solved by the invention]

The problem lies in how precisely the front end surface of the rib 25 for guiding the tape 2 should be formed. The surface precision of the relevant location is an important part in preventing the tape 2 from being scratched and ensuring running with low friction. -Generally, half-case molding molds are made by electric discharge machining, but the tape guide parts, which require particularly high surface precision, are made by mirror electric discharge machining.

This mirror electric discharge machining is advantageous because the surface roughness of the tape guide surface can be suppressed to 1.0 to 2.0 μmRmax, and manual post-processing can be omitted.

However, the central tape guide pin 15 and the side ribs 2
When drilling concave portions such as holes and grooves corresponding to No. 5 in a mold by mirror electric discharge machining, there is a minimum dimension that can be machined.

Therefore, since the central tape guide pin 15 has a diameter of 1.6 mm, the hole for it can be finished by mirror electric discharge machining, but the thickness (left and right width dimension) of the conventional rib 25 is 1.6 mm.
．． Since there are only 0 fins, the groove for this, especially the concave arc-shaped wall surface corresponding to the important front end arc surface of the rib 25, cannot be finished by mirror electric discharge machining, and the corresponding part has to be manually processed after finishing to make it mirror-finish. was required separately.

Therefore, the inventor of the present invention increased the wall thickness of the corresponding rib 25 to the same extent as the diameter of the central tape guide pin 15.
We considered forming grooves corresponding to the ribs 25 in the mold by mirror electric discharge machining. However, unlike the central tape guide pin 15, the rib 25 has a large front-to-back dimension, so increasing the wall thickness causes sink marks on the outer surface of the case, resulting in poor appearance and poor accuracy due to the sink marks.

These problems can be solved by forming the tape guide member as a guide pro vine separate from the upper and lower half cases, as seen in JP-A-1-199378, for example, but in this case, it takes time and effort to assemble. I can't escape the disadvantage.

From this point of view, an object of the present invention is to improve the tape guides to be arranged on the front left and right sides of the erasing head insertion window and the pinch roller insertion core, and to form the tape guide members at six locations on the front of the case by mirror electric discharge machining. To obtain a tape cartridge which can be molded with high precision using a molding die without causing sink marks at the corresponding part.

Another object of the present invention is to provide a tape cartridge which ensures stable tape running in each tape guide portion and which does not cause the phenomenon of tape getting caught.

[Means to solve the problem]

The present invention provides a tape cartridge having the above-mentioned basic configuration, in which central tape guide pins 15 are integrally erected high from the lower half case ib on the left and right sides of the front side of the recording/reproducing head insertion window 7, and an erasing head is inserted. Side tape guide pins 16, 16 are integrally and erected high from the lower half case 1b on the front left and right sides of the large window 8 and the pinch roller insertion window 9, respectively, and each side tape guide pin 16 and the partition wall. 5 are integrally erected from the lower half case 1b and are connected in series by a rib 25 lower than the pin 16, and the diameter of each side tape guide pin 16 is the same as the diameter of the central tape guide pin 15. The requirement is that the thickness is substantially the same as that of the rib 25, and is set larger than the thickness of the rib 25.

The thickness of the rib 25 is set to be less than the sink mark limit dimension.

In other words, if the thickness of the rib 25 increases beyond a predetermined value, sink marks will occur, so this sink limit dimension means the allowable limit value when sink marks occur on the case surface, and the protrusion height of the rib 25 is There is some width depending on the size etc.

[Effect]

If the side tape guide pin 16 is set upright away from the front end of the rib 25, a gap will be created between the two 25 and 16, and if the tape is suddenly stopped during fast forwarding, the loosened tape 2 will fill the gap. The tape gets stuck and gets stuck, making it impossible for the tape to run. In the present invention, the front end of the rib 25 is integrally connected to the root portion of the side tape guide pin 16 in order to prevent such a tape jamming phenomenon.

Set the side tape guide pin 16 higher than the rib 25.
The purpose of erecting the pin 16 low is to prevent sink marks during molding due to differences in wall thickness, including the pin 16, and to ensure the vertical accuracy of the pin 16.

〔Effect of the invention〕

Each side tape guide pin 16 in the erasing head insertion window 8 and the pinch roller insertion window 9 is connected to the recording/reproducing head insertion window 7.
Since the diameter is set to be approximately the same as that of the central tape guide pin 15 in the mold, the surface of the molding hole 16a of the side tape guide pin 16 in the mold can be finished by mirror electric discharge machining together with the central tape guide pin 15. Manual post-processing to create a mirror finish, which was essential during mold production, can be omitted. Manual surface finishing tends to cause variations in the finished state depending on the skill level of the worker, but this variation can be eliminated and the shape, position, and posture accuracy of each tape guide pin 15 and 16 after molding can be made uniform. be able to. Moreover, since all of these tape guide pins 15 and 16 are arranged together on the lower half case 1b side, compared to a form in which the upper and lower half cases 1a and 1b are molded symmetrically in two different ways. Therefore, in this respect as well, positional accuracy is improved, and overall stability of tape running can be expected.

Since the thickness of the rib 25 is set to be smaller than the diameter of the side tape guide pin 16, it is possible to prevent hairs from forming where the rib 25 exists.

Moreover, since the rib 25 is integrally connected to the base of the side tape guide pin 16 that protrudes higher than this,
Side tape guide pin 1 for sudden stops during tape fast forwarding, etc.
It is also possible to reliably prevent the loose tape 2 from being caught on the inner back side of the tape 6.

[Embodiment] FIGS. 1 to 5 show an embodiment of a tape cartridge according to the present invention.

In Fig. 4, the main body case 1 is an upper and lower half case 1a and 1b, each of which is separately molded by plus-sealing.
A pair of hubs 3 and 2 are wrapped around each other with tape 2 on the left and right inside of the main body case 1 (see Fig. 3).
3 is arranged rotatably, guide rollers 4 are arranged near the left and right ends of the front inside the main body case 1, and the tape 2 runs in a straight line on the front of the case via both rollers 4 and 4. It constitutes P. A partition wall 5 that partitions the inside of the main case 1 into front and rear parts along this tape running path P (see Fig. 1)
is provided.

On the front of the main body case 1, there is a recording/playback slot insertion window 7 in the center.
is formed, and an erase gutter insertion window 8 and a pinch roller insertion window 9 are formed at symmetrical positions of these, and even if the main body case 1 is used upside down, these insertion windows 7 are always closed.・At 8 and 9, the recording/reproducing head 10 on the deck side goes to erase. ・The gutter 11 and the pinch roller 12 enter from the front side, and the tape 2 is fed at a constant speed by the pinch roller 12 and the capstan shaft 13 that circumscribes it. It will be done.

As shown in FIG. 1, central tape guide pins 15 with circular cross sections are located on the front left and right sides of the central recording/reproducing head insertion window 7.
5 is integrally and highly erected from the lower half case 1b. The central tape guide pins 15 are conventional.

However, as shown in FIGS. 2 and 3, side tape guide pins 16, 16 with a circular cross section are attached to the front left and right sides of the erasing head insertion window 8 and the pinch roller insertion window 9 from the lower half case 1b. Stand tall as one. Each side tape guide pin 16 and the partition wall 5 are connected in series by the rib 25 which is integrally erected from the lower half case 1b and is lower than the pin 16. This rib 25 is substantially the same as that of the conventional example, but is fundamentally different from the conventional example in that a lateral tape guide pin 16 is erected in a continuous manner at the front end of the rib 25.

In FIG. 4, reference numeral 17 is a drive shaft on the deck side that rotationally drives the hub 3, 18 is a positioning pin on the deck side, and 19 is a recording/reproducing head insertion window 7 for pressing the tape 2 against the recording/reproducing head 10 on the deck side. It is a head pad placed deep inside.

A front end wall 2 that partitions the partition wall 5 and each insertion window 7, 8, and 9.
0, and the peripheral side walls are the upper and lower half cases 1a and 1b.
The tape guide pins 15 and 16 provided along the tape running path P are gathered on the lower half case 1b side and integrally protrude high from the case 1b. By consolidating the tape guide pins 15 and 16 on the lower half case 1b side, the processing standards of the molds for forming these tape guide pins 15 and 16 are unified, and variations in the accuracy of their shapes, positions, and postures are avoided.

In this way, the front end of the shorter rib 25 is connected to the base of each side tape guide pin 16, and the diameter of the side tape guide pin 16 is set to the diameter of the center tape guide pin 15. Set the same. Furthermore, the rib 2
The thickness (horizontal width) of 5 is the side tape guide pin 16.
It is smaller than the diameter of the upper and lower half cases, and is set to below the conventional sinkage limit dimension, and the protrusion height is set to be smaller than the upper and lower half case 1.
The height was set lower than the height of the joint surfaces of a and 1b.

Specifically, the diameter of each side tape guide pin 16 was set to 1.6 fi, which is the same as that of the center tape guide pin 15, and the thickness of the rib 25 was set to 1.01.

In this case, the tape 2 is guided by six tape guide pins 15 and 16 along the tape running path P on the front surface of the case. Since the side tape guide pins 16 and the ribs 25 are connected, even if the tape 2 loosens behind the side tape guide pins 16 when the tape 2 is suddenly stopped during fast forwarding, it will not get caught. .

As mentioned above, the side tape guide pin 1 is attached to the front end of the rib 25.
6, when forming the molding hole 16a for forming the pin 16 in the molding die as shown in FIG.
When the processing electrode 26 was inserted into the forming hole 16a, a sufficient clearance was secured around it, and the surface of the inner surface of the hole could be finished without any problem. By the way, normal electrical discharge machining can only achieve a surface roughness of around 15 to 20 μmRmax, and jig polishing can only achieve a surface roughness of about 6 μmRmax, but mirror electrical discharge machining can achieve a surface roughness of 1 to 2 μrnRmax. Ta.

FIG. 3 shows the state in which the upper and lower half cases 1a and 1b are joined, and the ribs 25 of each side tape guide pin 16 located on the inner side of the case, and the wall ribs 27 that protrude downward from the upper case 1a. This fills the space between the pin 16 and the partition wall 5.

[Brief explanation of the drawing]

Figure 1 is a plan view of the inside of the lower half case showing the tape running route, Figure 2 is a sectional view taken along line A-A in Figure 1, and Figure 3 is a cross-sectional view of the lower half case.
FIG. 4 is a plan view illustrating the internal state of the tape cartridge during use, and FIG. 5 is an explanatory diagram showing the finishing state of the molding die. 1... Main body case, 1a... Upper half case, 1b... Lower half case, 2... Tape, 5... Partition wall, 7... Recording/reproducing head insertion window, 8... Erasing head insertion window, 9... Pinch roller insertion core, 15... Center tape guide pin, 16... Side tape guide pin, 25 ...Rib, P...Tape running route.

Claims (1)

[Claims] 1. Plastic upper and lower half cases (1a and 1b)
A partition wall (5) that partitions the inside of the main case (1) into front and back is provided along the tape running path (P) on the front of the main case (1), which is formed by joining the main case (1) in a lid-to-bottom manner. On the front side of (1), there is a recording/reproducing head insertion window (7) in the center, and an erasing head insertion window (8) is located symmetrically to this.
) and a pinch roller insertion window (9), the recording/reproducing head insertion window (
7) Central tape guide pins (15, 15) on the front left and right sides
are integrally erected high from the lower half case (1b), and lateral tape guide pins (16, 16 ) is integrally erected high from the lower half case (1b), and each side tape guide pin (16) and the partition wall (5) are integrally erected from the lower half case (1b). They are connected in series by ribs (25) lower than the pins (16), the diameter of each side tape guide pin (16) being approximately the same as the diameter of the central tape guide pin (15), and the ribs ( 25) A tape cartridge characterized in that the thickness dimension is set larger than the thickness dimension of item 25).