JPS6331265Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention relates to a tape cassette that is composed of a tape storage case for storing tape and an opening/closing lid.

BACKGROUND OF THE INVENTION In general, tape cassettes for VTRs have a structure in which a lid is provided on the front surface of a tape storage housing to open and close the lid by rotating the tape cassette. There is also a tape cassette in which the lid is opened and closed by moving the protruding portion of the lid along a cam groove or a guide groove on the vertical wall of the casing. In this tape cassette, it is necessary to fit the protrusion into the groove during assembly.
The grooves are formed with approximately the same width up to their upper ends,
The part of the protrusion that is the entrance into the groove is narrow;
There was a problem in that it was difficult to fit the protrusion into the groove during assembly, resulting in poor assembly efficiency.

Means for Solving the Problems The purpose of the present invention is to provide a tape cassette that solves the above problems. In a tape cassette comprising a tape protection lid that covers the tape forming the tape path on the front side of the body, the tape cassette is provided on an upright portion of the casing and guides the protruding portion of the lid when the lid is moved. The groove has a shape in which the upper end opening, which is the entrance into which the protrusion enters when the tape cassette is assembled, is wider than the other part.

Embodiment FIGS. 1A, B, and C and FIG. 2 each show an embodiment of the tape cassette according to the present invention. In each figure, a tape cassette 1 has a cassette housing 2 and a front surface 2.
It is roughly composed of the opening/closing lid 3 on the A side.

As shown in Fig. 3, the cassette housing 2 includes an upper half 4 and a lower half 5 (both made of ABS resin).
Inside, a supply reel 6 and a take-up reel 7 are urged toward the lower half 5 by a substantially V-shaped reel holding plate spring 8 fixed to the upper half 4. It is stored away. Reference numeral 9 denotes a reel brake mechanism, which is provided inside the housing 2 near the back surface 2B. On the front side of the lower half 5, the central part is a notch opening 5a for inserting a loading pole, and the left and right ends are front projecting parts 5b and 5c that are relatively swung forward, and the cassette height is adjusted along the outer edges of these parts. It has a vertical wall that is 1/2 the height of the building. Particularly, the part of this vertical wall facing the left and right sides of the notch opening 5a is different from the other parts.
It is set as 0,11. This full height vertical wall 10, 11
, substantially S-shaped cam grooves 10a, 11a for opening and closing the lid are formed on the surface facing the notch opening 5a, and semi-cylindrical tape guides 10b, 11b are formed on the opposite surface.

The magnetic tape 12 is pulled out from the supply reel 6, passes through the overhang 5b, is guided by the tape guide 11b, comes out of the overhang 5b, and enters the notch opening 5.
The tape path 1 crosses the front side of the tape a, enters another overhang 5a, is guided by a tape guide 10b, passes through the overhang 5a, and reaches the take-up reel 7.
Form 2A. Tape guides 10b, 11b
The magnetic tape 12 guides the tape at the entrance/exit of the cassette case 2 even when the magnetic tape 12 is pulled out of the tape cassette. Here, tape guide 10
b, 11b are not formed by combining the hanging of the upper and lower halves and the tape guides formed on the vertical walls, but are formed on the full-height vertical walls 10, 11, so there are no steps in the middle in the height direction. To properly guide the magnetic tape 12 without fear of damaging it.

The opening/closing lid 3 has a structure in which an outer lid body 20 and an inner lid body 21 are combined, and is assembled on the front surface 2A side of the cassette housing 2, and is closed as shown in FIG. The lid is opened as shown in Figure 4. In the closed state, the outer cover 20 and the inner cover 21 work together to cover the magnetic tape 12 on its outside and inside.

The outer lid body 20 generally includes a front wall 20a that extends to a part of the upper surface of the cassette housing 2, left and right side walls 20b, 20c, and hanging arms 20d, 20e for supporting the inner lid body. Hanging arm portion 20d, 2
0e hangs down from the front wall 20a so as to closely oppose the surface of the full-height vertical walls 10, 11 on the side of the notch opening 5a. This outer lid body 20 is shown in FIGS.
As shown in the enlarged view, the side walls 20b, 2
The shafts 20b-1 and 20c-1 approximately at the center of the tape cassette 1 are held in bearings formed by the vertical wall of the lower half 5 and the hanging wall of the upper half 4, respectively, and It is rotatably supported at a substantially central position.

The inner lid body 21 roughly includes an elongated upper plate 21a,
Inner wall 21 protrudes diagonally downward and forward from this point.
It consists of b. The inner wall 21b has a hanging arm portion 20d,
The width dimension is slightly smaller than the dimension between 20e and 20e, and there is a protrusion 21c (the other is not shown), which is a supporting shaft protruding laterally at approximately the center of the side end surface, and an arm portion 21d (the other is not shown) on the lower side. (not shown). This inner lid body 21 has protrusions 21c and hanging arm portions 20d and 20e.
The shaft portion 21e (the other not shown), which is a cam follower on the distal end side of the arm portion 21d, is movably fitted into the cam groove 10a. That is, the inner lid 21 is connected to the cassette housing 2 by fitting the shaft portion 21e into the corresponding cam grooves 10a, 11a, and the outer lid 21 is connected to the left and right ends of the inner wall 21b. It is rotatably supported on the wall side, and its rotational attitude relative to the outer lid body 20 is controlled by cam grooves 10a and 11a.

In the closed state, as shown in FIG. 2, the outer cover 20 rotates counterclockwise, and the inner cover 21
The shaft portion 21e is guided and regulated by the lower position _P1 of the cam groove 10a and rotates clockwise, and the lower edge of the inner wall 21b is in contact with the lower edge of the front wall 21a of the outer lid body 21. . As a result, the notch opening 5
The magnetic tape 12 that crosses the front of a is covered on its surface and upper edge by the front wall 21a of the outer cover 21,
The back surface and lower edge side are covered by the inner wall 21b of the inner lid body 21 and are completely protected. Further, the elongated upper plate 21a of the inner lid body 21 is located at the same height as the top plate 4a of the upper half 4, and covers the upper opening of the cassette housing 2 near the front side. The opening/closing lid 3 is equipped with a torsion coil spring 22 as shown in FIG.
The lid is biased toward the lid closing direction, and is locked in the lid closing position by a locking mechanism that will be described later. The torsion coil spring 22 is fitted onto the shaft 20c-1, and has one arm secured to a protrusion 23 on the side surface of the upper half 4, and the other arm secured to a protrusion 20c-2 on the side wall 20c. There is.

When the tape cassette 1 is inserted into the device and the pop-up mechanism reaches the operating position, the locking mechanism of the opening/closing lid 3 is released as shown in FIG. 6 (this will be described later), and the device is opened. When the side pins 24 come into contact with each other, the outer lid body 20 is rotated approximately 90 degrees clockwise against the spring 22 to be opened. The inner lid body 21 has left and right shaft portions 21e guided by corresponding cam grooves 10a and 11a,
It rotates counterclockwise relative to the outer lid 20, and the lower edge of the inner wall 21b moves clockwise around the shafts 20b-1 and 20c-1 while avoiding the magnetic tape 12. That is, the cam grooves 10a and 11a are shaped so that the lower edge of the inner wall 21b moves in a detour so that the lower edge of the inner wall 21b does not catch the tape and damage the tape during the lid opening operation.
Here, the cam grooves 10a, 11a are not formed by connecting partial cam grooves formed in the vertical walls of the upper and lower halves, but are formed in one vertical wall 10, 11 over the entire length. Because of this, the structure is such that no connection step part appears in the middle, and the cam accuracy is also improved. Therefore, when the lid is opened and closed, the shaft portion 21e moves smoothly within the corresponding cam grooves 10a and 11a without being caught in the middle, and the inner lid body 21 rotates stably. Most importantly, even after the lid 3 is opened and closed many times, the shaft portion 21e does not shake within the cam groove 10a, and the opening/closing lid 3 and its associated mechanism have high reliability.

Note that when the lid is open, the inner lid body 21 has the protrusion 21
c and the shaft portion 21e that fits into the upper position _P2 of the cam groove 10a, and is in the state shown in FIG. 4. The elongated upper plate 21a is not in contact with the upper surface of the top plate 4a of the upper half 4, but is in a state slightly floating above this, and the structure of the opening/closing lid 3 is positively provided with a margin. That is, even if there are dimensional variations in each part, the inner lid body 21 is prevented from being tightly pressed from both sides by the upper half top plate and the cam groove.

Further, when the force in the opening direction by the pin 24 is released, the opening/closing lid 3 is rotated counterclockwise by the spring 22 and automatically enters the closed lid state shown in FIGS. 2 and 5. In addition, in the closed state, as shown in FIG. 1B, the outer wall body 20 has notches 20a-1 and 20a-2 on the left and right sides of the lower edge of the front wall 20a at the tips of the front overhangs 5b and 5c of the lower half 5. Projection portion 5b-1,
5c-1, and the upper plate 21a of the inner lid body 21 is fitted between the left and right side walls 20b and 20c of the outer lid body 20, so that displacement in the left-right direction in the figure is restricted.

The opening/closing lid 3 is locked in the closed position by a locking mechanism 30 provided on the right side wall of the cassette housing 2. This lock mechanism 30 is generally composed of a lock lever 31. As shown in FIGS. 1A and 5 and 5 to 7, the lock lever 31 is integrally formed with a slender arm 34 in addition to a lock engaging arm 32 and a lock releasing arm 33. A flat space 35 between the outer side wall 4b and the inner side wall 4c of the upper half 4 and a flat space 36 between the outer side wall 5d and the inner side wall 5e of the lower half 5.
(continuous with the flat space 35);
The upper part is pivotally supported by a pin 37 embedded in the upper half 4. As shown in FIG. 5, the opening/closing lid 3 has a hook portion of an engaging arm portion 32 for locking an approximately home base-shaped engaging protrusion 20c-3 protruding inside the side wall 20c of the outer lid body 20. 32a to lock the lid in the closed position.

The elongated arm portion 34 is configured to be elastically flexible and functions as a leaf spring. In FIG. 5, this elongated arm portion 34 is formed so as to protrude upward from the middle of the locking engagement arm portion 32, curve counterclockwise, and extend to the left. It becomes as shown by the chain double-dashed line in the figure. The elongated arm portion 34 is engaged with the protrusion 25 on the upper half side wall with its tip side bent in a direction away from the locking engagement arm portion 32, and the lock lever 31 is moved by the elastic force of the elongated arm portion 34. The hook portion 32 is in a clockwise rotationally biased state.
a is actively engaged with the engagement protrusion 20c-3. The elongated arm 34 is used to restrict the rotational position of the lock lever 31 when assembling the cassette, as will be described later.

Further, a protrusion 33a that protrudes laterally is provided at the lowest part of the lock release arm 33.
a is a space 38 below the outer side wall 5d of the lower half 5;
It is located inside the cassette without protruding from the side of the cassette case. Note that this protrusion 33a is effectively utilized when assembling the cassette, as will be described later.

The locking mechanism 30 described above is released by a lock release lever on the device side when the cassette is installed. That is, by horizontally inserting the tape cassette 1 to the final position, the lock release lever 40, which has relatively entered through the lock release lever entry port 39 (see FIG. 1B), engages the lock release arm of the lock lever 31. Press the bottom of 33 relatively. As a result, the lock lever 31 rotates counterclockwise against the elastic bending force of the elongated arm 34, as shown in FIG. Ru. In addition, the lock mechanism 3
0 is a lock release lever 41 inserted from below.
The lock is also released in the same way as in the above case.

Next, the optical tape end detection means will be explained with reference to FIGS. 1A and 1C.

The cassette housing 2 is provided with a cylindrical lamp accommodating portion 50 for accommodating a tape end detection lamp at the upper center in the left-right direction and at a position facing the notch opening 5a. Moreover, each side wall 20b, 2 of the outer lid body 20
0c is provided with a rectangular opening 20c-5 (the other one is not shown). As shown in FIG. 6, this opening 20c-5 aligns with the opening 51 in the side wall of the cassette housing 2 when the lid 3 is in an open state, so that the opening 51 is in an open state. The side walls 20b and 20c also function as shutters for the opening 51, and close the opening 51 when the lid 3 is closed, as shown in FIG.

The tape cassette 1 is mounted with the lid 3 open at a position where the left and right openings 51 (the other is not shown) face the light receiving elements 52 and 53 of the device elements.
Thereby, the light from the tape end detection lamp 54 housed in the lamp housing section 50 forms an optical path _L1 toward the light receiving element 53 through the opening 51 and the opening 20c-5 on one side, and the same on the other side. An optical path L ₂ passing through the opening toward the light receiving element 52 is formed.
Both ends of the magnetic tape serve as transparent leader and trailer tapes. Thereby, the end of the tape is optically detected by the lamp 54 and the light receiving elements 52 and 53. Further, the optical paths L ₁ and L ₂ are formed in the tape cassette 1 at a position near the opening/closing lid 3, passing between the upper and lower reel flanges of the supply reel and the take-up reel, respectively.

Next, a window for visually checking the winding state of the tape from the outside (hereinafter referred to as a transparent window for checking the tape winding state) will be described with reference to FIGS. 8A and 8B.

The transparent window 60 for checking the tape winding state has a substantially rectangular shape, and is located on the rear surface 2B of the upper surface of the cassette housing 2.
It is placed in a nearby position. The transparent window 60 has a structure in which a transparent plate 61 shown in FIGS. 8A and 8B is fitted into the elongated opening 4d of the upper half 4 from the inside and fixed by adhesive. The transparent plate 61 has a stepped portion 61a with a slightly lowered peripheral edge, and has notches 61b and 61c on the upper and lower sides of the upper center in the left-right direction in FIG. 8A. It is fitted into the brake stopper rib 4e hanging down from the top plate 4a of the upper half 4, and is positioned and installed. Here, the positioning notches are 61b and 61c.
The transparent plate 61 is provided on both sides as shown in
is not limited in its orientation in the left-right direction, that is, it can be installed in either direction upwards in the left-right direction, and has good assembly workability.

In addition, since the transparent window 60 is disposed on the upper surface of the cassette housing 2 at a position closer to the back surface 2B, this position is located closer to the optical paths L ₁ , L ₂ and the openings 51 , 20 c -
It will be located further away than 5. Therefore, even if light from the outside enters the cassette housing 2 through the transparent window 60 when the cassette is installed, the entered light will not reach the opening 51 through the outside of the tape loop inside the cassette. This prevents malfunctions such as erroneously detecting the end of the tape due to external light. Therefore, this arrangement of the transparent window 60 is particularly effective when applied to small tape cassettes. Furthermore, even when looking into the inside of the cassette through the transparent window 60, the leaf spring 8 for holding the reel is not visible, which is preferable from a design point of view.

Next, the mounting structure of the reel holding plate spring 8 to the upper half 4 will be explained with particular reference to FIGS. 1A and 2.

A standard type tape cassette has a large cassette housing, and the leaf springs are fixed by heat welding with a plurality of holes fitted into a plurality of corresponding projections provided on the upper half. However, if this mounting structure is applied to a small tape cassette as it is, the area where the leaf spring is fixed will become smaller.
The diameter of the projection on the upper half is small, and the strength of the fixing portion is extremely weak, resulting in a lack of reliability.

Therefore, in the above tape cassette 1,
The plate spring 8 has a fixed portion with a hole 8a in the center and a cutout recess 8b at one end, and the upper half 4 has a cylindrical projection 4f protruding from the top plate 4a and a lamp. A rib protrusion 4g is provided at a corner of the outer circumferential wall of the storage portion 50 and the top plate 4a. leaf spring 8
The hole 8a is fitted into the cylindrical projection 4f, the notched recess 8b is fitted into the rib projection 4g, and the two are fixed by heat welding.

Here, since there is only one hole 8a, even if the area of the contact portion with the upper half of the leaf spring 8 is narrow, the diameter is equal to or larger than the diameter of the hole in the leaf spring of the standard tape cassette. . Correspondingly, the diameter of the cylindrical projection 4f is the same as that of the standard tape cassette. Therefore, the leaf spring 8 is sufficiently firmly fixed by the cylindrical projection 4f and further reinforced by the rib projection 4g. In addition, the rib protrusion 4g and the notch recess 8b are connected to the leaf spring 8.
The function is to determine the orientation when installed.

Next, the reel brake mechanism 9 will be explained with reference to FIGS. 1A, 2, and 3.

The brake structure includes a brake main body member 70 having a substantially cubic shape, and a member 7 whose tips are separated from each other to the left and right.
It consists of flexible brake pieces 71 and 72 in the form of an integral thin plate, which are implanted at the bottom of the brake pad. The member 70 is
Ribs 5f protrude from the lower half 5 on the left and right sides,
5g, the upper side is regulated in position by the brake stopper rib 4e on the upper half 4 side,
It can move on the bottom plate of the lower half 5 in the directions of arrows A ₁ and A ₂ . In a normal state, the member 70 is biased in the direction of arrow _A1 by the compression coil spring 73 and moves in the same direction, and the brake pieces 71 and 72 are attached to the lower flanges of the supply reel 6 and the take-up reel 7, respectively. It meshes with the teeth 74 and 75 on the periphery to brake both reels. At this time, the member 70 is moved just before its movement is restricted by the integral stopper projections 5h and 5i protruding from the lower half 5 in order to prevent the member 70 from moving more than a predetermined amount in the direction of arrow _A1 . It is located at

When the tape cassette 1 is installed in the device, the brake release rod 76 having a conical tip on the device side enters the cassette through the bottom opening 5j of the lower half 5.
Push the inclined surface 70a of the through hole of the member 70 to remove the member 7.
0 in _{the two} directions of arrow A against the spring 73 (move it backward). As the member 70 retreats, the pair of brake pieces 71, 72 move to the stopper protrusions 5h, 5i.
The tip side narrows and retreats while being guided by the reels 6, 7, and separates from the corresponding teeth 74, 75.
The brake is released. In addition, the stopper protrusion 5h,
5i serves not only as a stopper for the member 70 but also to restrict the spread of the brake pieces 71 and 72.

Next, a working method for assembling the tape cassette 1 having the above structure by combining the upper and lower halves and a structure for facilitating this assembly work will be described.

The tape cassette 1 is assembled with the opening/closing lid 3 temporarily assembled to the upper half 4 in the maximum open state as shown in FIG. 9, and with the lock lever 31 assembled to the upper half 4 as shown in FIG. In this state, as will be described later, the upper half 4 and the lower half 5 are assembled vertically.

First, the supply reel 6 and take-up reel 7 are placed in the lower half 5, and the magnetic tape 12 is pulled out to form a tape path 12A that is guided by the tape guide parts 10b and 11b and crosses in front of the opening 5a. . The work of forming this tape path 12A is extremely simple compared to the case where the tape path is formed when the upper and lower halves 4 and 5 are combined.

The upper half 4 to which the opening/closing lid 3 and the lock lever 31 are assembled is moved down so as to cover the lower half 5 and assembled to the lower half 5.

During this assembly, the shaft portion 21e of the opening/closing lid 3 enters into the upper end opening 10a-1 of the cam groove 10a from above, and enters into the cam groove 10a by the closing operation after assembly.

Here, when the opening/closing lid 3 is opened/closed, the shaft portion 21e is guided by the cam groove 10a and moves to a position _P1.
and a position slightly in front of the upper end opening 10a-1.
_P2 , and the area between position _P2 and the opening end is a section that is not used as a cam groove. Therefore, the position
The opening 10a-1 between _P2 and the open end is made wide so that the shaft portion 21e can be more easily inserted during assembly, and a mold that can be easily manufactured can be used.

That is, the opening 10a-1 has a vertical portion 10a-2 and a horizontal portion 10a, as shown in FIGS. 3 and 9.
-3, and the upper end extends both upwardly in the width direction of the cam groove 10a, especially in the horizontal part 10a-3.
It is wide and spreads out on three sides. Here, the vertical part 10
A-2 serves to widen the groove width of the cam groove 10a in the left direction in FIG. 3, and the horizontal portion 10a-3 serves to widen it in the right direction in the same figure. Therefore, when the upper and lower halves are assembled, the shaft portion 21e can easily fit into the opening 10a-1 through the wide opening as shown by the arrow in FIG. 9, and can also easily fit into the substantial cam groove. can enter. Therefore, the opening/closing lid 3 is inserted into the left and right cam grooves 10a, 1.
The work of fitting with 1a is easy. Also,
Instead of the horizontal portion 10a-3, as shown by the two-dot chain line in FIG. 9, an oblique straight portion 10a-4 may be used.
Similarly, a wide open end can be formed, and the same effects as in the above case can be achieved in terms of assembly work.

Next, the action of the lock lever 31 when assembling the upper and lower halves will be explained. The lock lever 31 is pivotally supported on the upper half 4 by a pin 37, and its elongated arm portion 34 is attached to the side projections 23 and 2 of the upper half 4.
It is installed with the protrusion 23 inserted between the
The free rotation range is restricted to a narrow angular range by the and protrusions 25. Further, when the upper half 4 is supported horizontally, the lock lever 31 is biased to rotate counterclockwise by its own weight, but the elongated arm 34 is locked to the protrusion 25, as shown in FIG. The rotating position is regulated as shown in the figure. The rotation restriction position of the lock lever 31 is determined by the protrusion 33a at the lower end of the lock release arm 33 when the upper half 4 is opposed to the position directly above the lower half 5.
is located at a position opposite to the side end surface 5d-1 of the outer side wall 5d of the lower half 5.

As a result, when the upper half 4 is brought close to the lower half 5, the protrusion 33a comes into contact with and guided by the side end surface 5d-1, as shown in FIG. Here, the side end surface 5d-1 is a curved surface 5d-2 with a lower portion protruding leftward. Therefore, when the upper half 4 is further moved down, the lock lever 31 is rotated clockwise with the protrusion 33a guided by the protruding curved surface 5d-2, as shown by the two-dot chain line in FIG. The portion 34 is engaged with the protrusion 23 and is elastically deformed to be charged with elastic force.

When the upper half 4 is moved down to the final position where it comes into contact with the upper surface of the lower half 5 and is combined with the lower half 5, the protrusion 33a is attached to the neck portion 5d-3 of the side end surface 5d-1.
As shown in FIG. Quickly returns to position due to spring force. The protrusion 33 passes over the nape 5d-3 and enters the space 38, and the lower surface 5 of the outer side wall 5d.
Opposite d-4. Therefore, even if some force acts to separate the upper and lower halves after they are seemingly assembled, the protrusion 33 and the lower surface 5d-4 will engage and prevent the upper and lower halves from separating. , and the temporary assembled state is kept stable. After this, the upper and lower halves 4 and 5 are screwed together to complete the tape cassette 1.

In addition, in the above configuration, when assembling the upper and lower halves, it is necessary to move the lock lever 31 to the side with your fingers so that it does not collide with the lower half 5 and interfere with the assembly, and to return it to its original position with your fingers after assembling. Since this is not necessary, the tape cassette 1 can be assembled with high efficiency.

The tape cassette 1 can also be assembled in the same manner by fixing the upper half 4 and raising the lower half 5.

Next, the structure of the mold for molding the cam groove 10a portion of the lower half 5 will be explained.

Since the cam groove 10a has a curved shape, the cam groove 1
The mold for forming 0a cannot be pulled out in the vertical direction of the vertical wall 10, but the mold is pulled out in the direction perpendicular to the wall surface of the wall 10. Further, due to the structure near the cam groove 10a, the mold has a structure that combines a mold for molding the cam groove 10a and a mold for molding the vertical wall facing the notch opening 5a.

FIG. 13 shows a portion of the lower half 5 around the cam groove 10a together with a mold for molding this portion. In the figure, A is a mold for molding the cam groove 10a and the tape cassette full-height vertical wall 10, and B is a mold for molding the vertical wall 80 mainly facing the notch opening 5a. After molding, mold A is first pulled out in the direction of the arrow, and then mold B is pulled out in a direction perpendicular to the plane of the paper.

Here, the problem is where to determine the separation plane between the molds A and B, but in this embodiment, the cam groove 10a has its upper end connected to the wide opening 1.
Considering that the shape is 0a-1, the third
In the figure, it is defined on a vertical plane including a line L passing through the starting end of the horizontal portion 10a-3. FIG. 14 shows the mold B taken out.

According to the above mold structure, the following effects are achieved.

The portion of the mold B where the horizontal portion 10a-3 is formed may be formed with a certain degree of precision.

When the separation plane is set at a position very close to the vertical wall 80 as shown by line M in FIG. 13 (the mold B' becomes as shown by the two-dot chain line in FIG. 14).
Compared to this, mold B has a shape with sufficient thickness even at its tip, and can be accurately molded. In addition, even if molding is performed many times, accidents such as breakage of the tip part are unlikely to occur, and mold B
has a highly durable structure.

The reason why the mold can have the above structure is that the cam groove 10a is defined so that the upper end portion thereof becomes an unused portion.

Effects As mentioned above, the tape cassette according to the present invention has the following various features.

Since the horizontal straight part and the vertical straight part form the upper end opening of the guide groove, the upper end opening has a shape that widens at a right angle, so that the opening width can be effectively increased.

Therefore, when assembling the cassette, it becomes easy for the protrusion to fit into the guide groove through the upper end opening, thereby simplifying the tape cassette assembly operation and improving the efficiency of the assembly operation.

Since the upper end opening is formed by a straight part, the mold should also have a structure that does not have sharp edges, that is, it must be durable enough to prevent damage to the edges even after repeated molding operations. It is possible to use a material with a structure rich in properties, and it is also convenient for molding.

There is no problem even if the precision of the upper end opening of the groove is lower than other parts, so the part that molds the upper end opening of the mold that forms the groove can be molded roughly, making the mold manufacturing that much easier. becomes.

[Brief explanation of drawings]

FIGS. 1A, B, and C are a partially cutaway plan view, front view, and right side view of an embodiment of the tape cassette according to the present invention, and FIG. A vertical side view, FIG. 3 is a diagram showing the upper and lower halves of the tape cassette housing separated, FIG. 4 is a sectional view showing the structure around the opening/closing lid when the opening/closing lid is open, and FIGS. 5 and 6 are The figures are enlarged side views showing the closed and open states of the opening/closing lid (outer lid body) together with the locking mechanism, etc., and FIG. 7 is a side view showing the lock lever assembled into the cassette housing. Figure 5 is a cross-sectional view taken along the line in Figure 5, Figures 8A and B are a plan view and a front view of the transparent plate for the transparent window, respectively, Figure 9 is the state of the opening/closing lid when the tape cassette is assembled, and the opening/closing lid. Figures 10, 11, and 12 are diagrams showing how to engage the lock lever and the lower half in stages when assembling the tape cassette, respectively. FIG. 13 is an enlarged view showing the peripheral part of the middle cam groove of the lower half together with the molding die, and FIG. 14 is a view showing one of the molds taken out. 1...Tape cassette, 2...Cassette housing,
2A...Front, 2B...Back, 3...Opening/closing lid, 4
... Upper half, 5 ... Lower half, 6 ... Supply reel, 7 ... Take-up reel, 10, 11 ... Tape cassette full height vertical wall, 10a, 11a ... Cam groove for opening and closing the lid, 10a-1 ... ...Top opening, 10a-2
...Vertical part, 10a-3...Horizontal part, 12...Magnetic tape, 20...Outer cover, 20a...Front wall, 20b, 20c...Side wall, 21...Inner cover, 21b...Inside Wall, 21e... Shaft, 30...
...Lock mechanism.

Claims (1)

[Scope of Claim for Utility Model Registration] Comprised of a casing for storing a tape inside, and a tape protection lid that covers the tape forming the front tape path of the casing when the lid is closed. A tape cassette comprising a guide groove provided in the upright part of the casing for guiding the protruding part of the lid during movement, wherein the upper end of the side wall of the casing near the front of the casing is a vertical straight part of the guide groove, A tape cassette having a structure in which the upper end of the other side wall is a horizontal straight part, and the vertical straight part and the horizontal straight part form the upper end opening of the guide groove.