JPH0514380Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a novel tape cassette. In detail, the subject relates to an improvement in the brake mechanism that locks the rotation of the tape reel in a tape cassette that stores tape such as magnetic tape. The aim is to provide a tape cassette with a wide range of functions.

BACKGROUND TECHNOLOGY AND PROBLEMS A tape cassette that stores tape such as magnetic tape wound around a tape reel is generally equipped with a brake mechanism for locking the rotation of the tape reel. This is because when the tape cassette is not in use, the tape reel rotates in the tape unwinding direction to loosen the tape, which may cause the tape to become tangled within the cassette case or cause the tape to unwind. This is necessary to prevent items from falling out of the cassette case. There are various forms of this type of brake mechanism, but generally it is equipped with a pawl that is removably engaged with the engaging part of the tape reel, and is rotatably supported by the cassette case. It is composed of a brake body, a spring member that rotationally urges the brake body toward the tape reel, and a release member that releases the brake applied by the brake body. When the tape cassette is not in use, the claw pieces are kept engaged with the engaging portion of the tape reel by the spring member, and when the tape reel is in use, the claw pieces are kept engaged with the engaging portion of the tape reel. is kept separated from the engaging portion of the tape reel by the release member.

FIG. 1 shows an example of a reel brake mechanism in a conventional tape cassette. In the figure, a indicates a lower half constituting a cassette case of a tape cassette, and b indicates a rear wall formed upright from the rear edge of the lower half a. For example, c is a lower flange of the tape reel on the tape supply side, and the outer peripheral edge of the flange c is formed with notches d, d, . Denoted at e is a brake body, whose cylindrical base f is rotatably fitted onto a pin g erected on the lower half a. h is a claw piece that stands upright from the outer peripheral surface of the base f toward the front, and a claw part i that is bent toward the flange c side of the tape reel is formed at the tip of the claw piece h. ing. j is an operating arm that protrudes laterally from the base f and is bent forward from the tip into an L-shape, and the base f of the operating arm j is
A protrusion is formed approximately at the center of the upper end surface of the side piece k.

m is a torsion spring, an intermediate ring-shaped part n is fitted onto a pin o provided upright on the lower half a, and the tip of one working arm p extending linearly from the lower end of the ring-shaped part n is operated as described above. It abuts against the side surface of a protrusion formed on the proximal side piece k of the arm j, and its tip rests on the upper end surface of the proximal side piece k of the operating arm j.

q is a brake release piece movably supported on the lower half a by appropriate means, and when the tape cassette is not in use, its pressing surface is the tip of the operating arm j of the brake body e. When the tape cassette is put into use, it is placed in the position shown in FIG. It is designed to be moved in the direction indicated by the arrow inside.

Although not shown, another brake body similar to the brake body e is provided on the right side in FIG. It is engaged with the tape reel on the receiving side. Further, the tip of the other acting part r extending from the upper end of the annular part n of the torsion spring m in a direction substantially opposite to the extending direction of the acting part p is engaged with the operating arm of the other brake body (not shown). .

Thus, in the brake body e, the protrusion formed on the operating arm j is biased with a rotational force in the counterclockwise direction by the spring force of one operating arm p of the spring m. Therefore, when the tape cassette is not in use, that is, when the tape cassette is not mounted on the tape deck, it is in the state shown by the solid line in FIG. are the notches d, d, ... of the flange c of the tape reel.
..., thereby locking the rotation of the tape reel. Also,
When the tape is attached to the tape deck, the release piece q is moved in the direction shown by the arrow in the figure by the brake release pin (not shown), and the brake body e is moved.
is rotated clockwise against the spring force of spring m, and is positioned at the position shown by the two-dot chain line in FIG. As a result, the claw portion i at the tip of the claw h of the brake body e is disengaged from the notches d, d, .

Although the reel brake mechanism in the conventional tape cassette shown in FIG. 1 is as described above, such a brake mechanism has serious operational problems. This is because when the brake body e is rotated in the direction of releasing the brake, there is a risk that the tip of one working arm p of the spring m may come out of the predetermined engagement position of the brake body e. It is.
That is, while the brake body e is moved from the position shown by the solid line to the position shown by the two-dot chain line in FIG. may be parallel to each other as shown by the one-dot chain line in FIG. In some cases, the tip of the acting arm p may slide down toward the side surface of the side piece k. Then, when the brake body e is further rotated clockwise with the tip of one working arm p of the spring m sliding down toward the side surface of the side piece k, the working arm p The tip of the brake body abuts against the inner surface of the rear wall b of the cassette case, and the middle part of the working arm p is pressed by the ridgeline of the L-shaped corner of the brake body e. (The state shown by the two-dot chain line in FIG. 1). In such a state, it is almost impossible for the tip of the working arm p to be engaged with the above-mentioned predetermined position of the brake body e again, and also to move the brake body e toward the brake release direction. As the rotation range of the tape reel is narrowed, the brake on the tape reel cannot be released sufficiently, and furthermore, the brake body e may bend the working arm p. Moreover, the brake body e
If the brake release piece q is not rotated to the predetermined brake release completion position, the brake release piece q will also not be moved to the predetermined movement completion position.As a result, if the tape cassette cannot be pushed into the tape deck to the predetermined set position, It can also cause malfunctions.

Purpose of the invention The present invention was devised in view of the above-mentioned problems, and the working part of the spring member that biases the brake body to rotate toward the tape reel side always engages with a predetermined engagement part of the brake body. A new reel brake mechanism equipped with a reel brake mechanism that allows the brake body to always operate stably, and also allows such stable operation to be performed with a simple structure. The purpose of the present invention is to provide a tape cassette with a wide range of functions.

Summary of the invention In order to achieve the above-mentioned purpose, the tape cassette of the invention engages a tape supply reel and a tape take-up reel on which tape is wound, and notches formed in the lower flanges of each of the tape reels. a pair of brake bodies for locking the rotation of the tape reel; a spring for urging the brake body to rotate toward the tape reel; and a release member for releasing the brake by the brake body; The pair of brake bodies are provided approximately symmetrically, and each includes a claw piece that removably engages with the tape reel, and a rotation fulcrum that is rotatably fitted onto a pin that is integrally erected on the lower half of the tape cassette. The operating arm is formed to protrude from a cylindrical base and is bent into a substantially L-shape, and one end of the release member commonly comes into contact with the operating arm. A relatively long 2.0mm diameter portion is fitted onto a narrow diameter portion formed through a stepped portion on the upper part of the vertical pin, is placed on the upper surface of the stepped portion, and extends linearly from both ends of the annular portion. The distal ends of the two operating arms are engaged with the engaging portions provided on the upper portions of the L-shaped operating arm base side arm pieces of the pair of brake bodies, and are positioned on the upper end surfaces of the operating arms. The vertical engagement surface of the engagement portion is a continuous surface with the wall surface of the L-shaped operating arm, and the operating arm is in a braking state such that the corner of the L-shaped bend is a straight portion extending to both ends of the spring. The corner portion is located at the front side of the cassette, and when the brake is released, the corner portion is rotated toward the rear side of the cassette across the straight line portion of the spring, and extends linearly from at least the lower end of the ring portion of the spring. The L-shaped bent corner of the operating arm of the brake body, which is provided with the engaging portion with which the tip of the arm is engaged, has a corner that is perpendicular to the wall surface of the L-shaped operating arm that is continuous with the vertical engagement surface. The present invention is characterized in that a slope is formed on the protrusion that protrudes in the direction to push the spring upward toward the upper end surface of the operating arm on the side of the engaging portion.

By doing so, it is possible to provide a novel tape cassette equipped with a brake mechanism that can perform stable operation with a simple structure without increasing manufacturing costs.

Embodiments Hereinafter, details of the tape cassette of the present invention will be explained according to embodiments shown in the accompanying drawings. The drawings show an example of an embodiment in which the tape cassette of the present invention is applied to a video tape cassette.

Reference numeral 1 designates a tape cassette for a video tape recorder, in which two tape reels 6 and 7 each having a magnetic tape 5 wound thereon from both ends are rotatably arranged in a cassette case 4 consisting of an upper half 2 and a lower half 3. The front part of the cassette case 4, which is the tape drawer part, is covered with a cover 8 which can be opened and closed. Cassette case 4
One of the tape reels 6 and 7 rotatably disposed inside the tape serves as a tape supply reel (hereinafter referred to as "S reel"), and the other 7 serves as a take-up reel (hereinafter referred to as "T reel"). The magnetic tape 5 pulled out from the S reel 6 is guided out of the cassette case 4 through an opening 9 formed near one edge of the front surface of the cassette case 4, and then
An opening 10 formed near the other edge of the front surface of the
is introduced into the cassette case 4, and the T reel 7
is wound up. Further, the magnetic tape 5 is placed along the outer peripheral surfaces of guide pins 11 and 12 provided near the other openings of the respective openings 9 and 10. 1
Reference numeral 3 denotes a recess for tape drawer operation, and a tape loading member (not shown) is positioned in the recess 13 when the tape cassette 1 is set in a predetermined setting position of a video tape recorder or the like. The magnetic tape 5 is pulled out from each tape reel 6 and 7 by the portion of the magnetic tape 5 passing through the front surface of the cassette case 4 being pulled by the tape loading member.

14 is a lower flange of the S reel 6, and the outer peripheral edge of the flange 14 has a notch 1 approximately shaped like a gear tooth.
5, 15, . . . are formed. Further, 16 is a lower flange of the T reel 7, and the flange 16
There is a notch 17,1 approximately in the shape of a gear tooth on the outer peripheral edge of the
7,... are formed.

Reference numeral 18 denotes an outer circumferential wall formed along the rear edge and both side edges of the lower half 3, and the outer circumferential wall 18 constitutes the side surface of the cassette case 4.

19 is a reel brake mechanism. The reel brake mechanism 19 is provided approximately at the center of the cassette case 4 near the rear edge. 20, 20,...
is a protrusion formed in a substantially isosceles triangular shape in the center near the rear edge of the lower half 3, and the reel brake mechanism 19 is connected to the protrusion 2.
0, 20, . . . and the rear side of the outer peripheral wall 18.

22 and 22' are brake bodies. One of the brake bodies 22, 22' is provided at a position closer to the S reel 6 side of the space 21, and the other 22' is provided at a position closer to the T reel 7 side of the space 21, and the other brake body 22' is provided at a position closer to the T reel 7 side of the space 21, The brake body 22 closer to the S reel 6 is the brake body on the S reel side that locks the rotation of the S reel 6, and the brake body 22 closer to the T reel 7 side is the brake body on the S reel side that locks the rotation of the S reel 6.
2' is a brake body on the T-reel side that locks the rotation of the T-reel 7.

23 and 23' are the bases of each brake body, and the bases 23 and 23' are formed into a substantially cylindrical shape,
It is rotatably supported by pins 24, 24' that are erected from the lower half 3 on both sides of the space 21 toward the rear.

25 and 25' are claw pieces of each brake body 22, 22', and the claw pieces 25, 25' are attached to the base parts 23, 2
It protrudes forward from the outer peripheral surface of 3'.
Each tip thereof projects out of the space 21 through openings 26, 26' provided in the protrusions 20, 20, . . . , respectively. 27, 27' are each claw piece 25,
The claws 27, 27' are formed by bending the tips of the tape reels 6, 7 toward the outside, respectively. They are adapted to be removably engaged with the notches 15, 15, . . . and 17, 17, .

28 and 28' are operating arms of each brake body 22, 22'. The operating arms 28, 28' are connected to the bases 23, 2
They protrude inwardly from the upper part of the outer circumferential surface of 3', and are further bent forward into a substantially L-shape. Further, substantially cylindrical operating portions 29, 29' extending in the vertical direction are formed at the distal ends of the distal arm pieces 28a, 28a' of each operating arm 28, 28'. Further, protrusions 30, 30' are formed approximately at the center of the upper end surfaces of the base side arm pieces 28b, 28b' of each of the operating arms 28, 28'. and,
The upper ends of the protrusions 30, 30' are formed with engaging pieces 31, 31' bent rearward at approximately right angles. Incidentally, the other projection 30' of the projections 30, 30' is formed to be taller than one projection 30.

32 is the operating arm 28 of the S reel side brake body 22
This is a corner bent into an L-shape, that is, a protrusion formed to protrude rearward from the tip of the rear side of the proximal arm piece 28b of the operating arm 28. The upper end surface 33 of the protrusion 32 is a slope that gradually approaches the lower half 3 from the base to the tip, and the proximal edge of the upper end surface 33 is connected to the base side arm piece 28.
It is located on the same plane as the upper end surface of b. The slope 33 of this protrusion 32 is such that the tip of one working arm of the spring, which will be described later, is always connected to the proximal arm piece 28 of the operating arm 28.
(a) so that it can be positioned on or above the upper end surface.

34 is a torsion spring, and an annular portion 35 formed in a coil shape in the middle thereof is externally connected to a narrow diameter portion 36b formed through a stepped portion 36a above a pin 36 erected in the rear central part of the space 21. Supported in a fitted manner. Incidentally, after the annular portion 35 of the spring 34 is fitted onto the outside, the upper end of the narrow diameter portion 36b may be caulked to prevent the spring 34 from coming off. and the ring-shaped portion 3 of the spring 34
The distal end of one operating arm 37 extending from the lower end of 5 to the side where the S reel side brake body 22 is located is attached to the rear side of a protrusion 30 that is erected on the base side arm piece 28b of the operating arm 28 of the brake body 22. It is in elastic contact, and its tip is engaged with the upper end surface of the proximal arm piece 28b, or is positioned so as to face from above the upper end surface. Further, the tip of the other operating arm 38 extending from the upper end of the annular portion 35 of the spring 34 to the side where the T-reel side brake body 22' is located is connected to the base side arm piece 28' of the operating arm 28' of the brake body 22'. The protrusion 30' b is in elastic contact with the rear surface of the protrusion 30', and its tip is positioned so as to face the upper end surface of the proximal arm piece 28'b from above.

Therefore, the brake body 22 on the S reel side is biased with rotational force in the counterclockwise direction by the spring force of one operating arm 37 of the spring 34, and
The brake body 22' on the reel side is connected to the other working arm 38.
The rotational force in the clockwise direction is applied by the spring force of . Therefore, when the tape cassette 1 is not in use, the claw piece 25 of the brake body 22
The claw portion 27 at the tip of the lower flange 1 of the S reel 6
4, and thereby the S reel 6 is locked from rotation. Similarly, the claw portion 27' at the tip of the claw piece 25' of the brake body 22' is attached to the lower flange 16 of the T reel 7.
are engaged with the notches 17, 17, . . . , thereby locking the T-reel 7 from rotation.

Reference numerals 39 and 39' denote protrusions formed on both sides of the center of the space 21, and the protrusions 39 and 39' extend forward from a downwardly located portion of the inner surface of the rear outer circumferential wall 18 of the cassette case 4. the protrusion 20 at the front end;
It is formed to be integrally connected to 20,
Notches 40, 40' that are open upward are formed in the center of each of the protrusions 39, 39'. The operating arms 28 and 28' of the brake bodies 22 and 22' are provided with protrusions 39 and 3, respectively.
9'. 41 is an insertion hole formed at a position corresponding to the front part of the space 21 of the lower half 3. This insertion hole 41 allows the tip of a brake release pin 42 provided on the video tape recorder side to pass through the insertion hole 41 and release the cassette when the tape cassette 1 is set at a predetermined setting position in a video tape recorder or the like. It is intended to be inserted into the case 4.

A brake release body 43 rotates the brake bodies 22 and 22' in the brake release direction.
44 is a substrate of the brake release body 43, and the space 2
1, and a cylindrical support shaft part 4 whose axis extends horizontally at the rear end.
5 is integrally formed, and protrusions 46, 46 are integrally formed in the center portions of both end surfaces of the support shaft portion 45, respectively. A pressing piece 47 is formed upwardly at a right angle from a position close to the support shaft 45 of the board 44, and the tip of the pressing piece 47 has a cross-sectional shape that projects rearward. A pressing portion 48 having a substantially semi-cylindrical shape is formed in the pressing portion 48 .
Reference numeral 49 denotes a reinforcing rib formed on the upper surface of the center portion of the substrate 44.

Therefore, the brake release body 43
A protrusion 3 having protrusions 46 and 46 at both ends, respectively.
It is rotatably supported in notches 40 and 40' formed in holes 9 and 39'. The rear surface of the pressing portion 48 is in contact with the front surface of each operating portion 29, 29' of the brake bodies 22 and 22', and the front portion of the base plate 44 is positioned so as to close the insertion hole 41.

Incidentally, 50 is the protrusion 20 on the lower surface of the upper half 2,
20, lower half 3 at the position corresponding to the front part of...
A protrusion formed to protrude toward 51,5
1' is a line extending from the protrusion 2 on the lower surface of the upper half 2 where the notches 40, 40' of the protrusion 39, 39' are formed.
This is a protrusion that is formed to protrude toward the lower half 3 at a position corresponding to the portion that connects with 0 and 20. Notches 40, 4 formed in the protrusions 39, 39' on the lower half 3 side of the protrusions 51, 51'
Protruding pieces 52, 52' protruding toward the notches 40, 40' are formed in the portion corresponding to 0',
Projections 4 on both ends of the support shaft portion 45 of the brake release body 43
6, 46 are cut out 4 by these projecting pieces 52, 52'.
It is prevented from coming off from 0.40'.

When the tape cassette 1 is set at the set position of the video tape recorder, the release pin 42 is inserted into the cassette case 4 through the insertion hole 41 formed in the lower half 3, and the release pin 42 is inserted into the cassette case 4 through the insertion hole 41 formed in the lower half 3.
Since the upper end pushes up the lower surface of the substrate 44 of the brake release body 43, the brake release body 43
It is rotated about the portion supported by the notches 40, 40' as the rotation center. Brake release body 4
3 is rotated, the pressing portion 48 formed at the tip of the pressing piece 47 of the brake release body 43 is displaced toward the rear of the space 21 (the state shown by the two-dot chain line in FIG. 4),
The pressing portion 48 presses the operating portions 29 and 29' of each brake body 22 and 22' toward the rear of the space 21. Then, the brake body 22 on the S reel side is rotated clockwise as its operating portion 29 is pressed, and the brake body 22' on the T reel side is rotated in the clockwise direction by its operating portion 29' being pressed. As a result, it is rotated counterclockwise and displaced as shown by the two-dot chain line in FIG. When each brake body 22 and 22' is displaced in this way, the claw portions 27 and 27' of each claw piece 25 and 25' of each brake body 22 and 22' are moved to the lower side of each tape reel 6 and 7. Notches 15, 15, ... and 17, 1 formed on the outer peripheral edge of the flanges 14, 16
7, . . . , thereby allowing each tape reel 6 and 7 to rotate freely. Further, while each of the brake bodies 22 and 22' is rotated as described above, the tips of the respective operating arms 37 and 38 of the spring 34 are
2 and 22' remain engaged with the predetermined engagement positions of the operating arms 28 and 28'. That is, first, since the other working arm 38 of the spring 34 extends from the upper end of the annular portion 35 as described above, its tip always moves upward in accordance with the characteristics of the upper working arm of this type of torsion spring. Since it has the property of displacing, the tip end is connected to the operating arm 28'.
Although the protrusion 30' formed on the proximal arm piece 28b' may move so as to come into contact with the lower surface of the engagement piece 31', the protrusion 30' may move downward from the position where it is engaged with the rear surface of the protrusion 30'. There is almost no movement. Therefore, the distal end of the other operating arm 38 of the spring 34 always remains engaged with the rear surface of the protrusion 30' while the brake body 22' is rotated as described above. Further, one operating arm 37 of the spring is always maintained in a predetermined engagement position and engaged state by the slope 33 of the protrusion 32 formed at the L-shaped bent corner of the operating arm 28. Continue to do so.

Next, the process by which one operating arm 37 of the spring 34 continues to be engaged with a predetermined engagement position of the operating arm 28 will be explained in detail with reference to FIGS. 6 and 7. As described above, one working arm 37 of the spring 34 extends from the lower end of the annular portion 35, so its tip always tends to displace downward in accordance with the characteristics of the lower working arm of this type of torsion spring. It has properties. However, the brake body 22
When is in the position shown by the solid line in FIG. Even if the portion attempts to displace downward, the distal end abuts against the upper end surface of the proximal arm piece 28b, so that it will not be displaced further downward. Therefore, the distal end of the working arm 37 remains engaged with the rear surface of the protrusion 30. Next, brake body 2
2 is rotated clockwise as described above, at a certain point, the tip of the working arm 37 becomes parallel to the rear surface of the base arm piece 28b (the sixth
state shown in Figure A and Figure 7A). In this state, the tip of the operating arm 37 is off the upper end surface of the proximal arm piece 28b, but the middle part of the operating arm 37 touches the slope 33 of the protrusion 32 formed at the corner of the operating arm 28. Therefore, even if the tip of the working arm 37 were to move downward in this state, the slope 33 would act to push up the middle part, so the working arm 37 would not move downward. It will not be displaced to Therefore, even in this state, the tip of the working arm 37 remains engaged with the rear surface of the protrusion 30. Then, as the brake body 22 is further rotated clockwise, the operating arm 3
The middle portion of the handle 7 gradually comes off the upper end edge of the slope 33 and comes to rest on the upper end surface of the corner of the operating arm 28. (The state shown in FIGS. 6B and 7B). Then, as the brake body 22 is further rotated clockwise, the middle part of the operating arm 37 is completely placed on the upper end surface of the corner of the operating arm 28, or the upper end surface is faced from above. As a result, the tip of the operating arm 37 remains in the projection 3 without moving downward.
remains engaged with the rear surface of 0.

Then, when the use of tape cassette 1 is finished,
When the tape cassette 1 is taken out from the set position of the video tape recorder, the brake bodies 22 and 22' are moved in the direction in which the brakes are applied to the tape reels 6 and 7 by the spring force of the acting arms 37 and 38 of the spring 34, respectively. and is returned to the position shown by the solid line in FIG. At the same time, the brake release body 43 is caused by the weight of the base plate 44.
Alternatively, the operation parts 29, 29' of the brake bodies 22 and 22' press the pressing part of the brake release body 43, thereby returning to the state shown by the solid line in FIG. Of course, even while the brake bodies 22 and 22' are returned to the position where they apply the brakes to the tape reels 6 and 7, the tips of the operating arms 37 and 38 of the spring 34 are still connected to the operating arm 2.
8 and 28' can be maintained at their respective predetermined engagement positions.

Modified Example FIG. 8 shows S of the reel brake mechanism 19 described above.
A modification example 22A of the reel-side brake body 22 is shown. The brake body 22A shown in FIG. 8 differs from the brake body 22 described above only in the slope at the upper end of the protrusion formed at the corner of the operating arm 28, so the corner of the brake body 22 described above The same parts will be given the same reference numerals as those given to the brake body 22, and the explanation will be omitted.

In FIG. 8, 53 is a protrusion formed at the tip of the rear side of the base arm piece 28b of the operating arm 28, and the upper end surface 54 of the protrusion 53 is the base arm piece 28b.
The slope gradually approaches the lower half from the edge on the tip side to the edge on the base 23 side. Even if the slope formed at the corner of the operating arm 28 is formed in this way, the tip of one operating arm 37 of the spring 34 always remains engaged with the predetermined engagement position of the projection 30. . That is, the brake body 2
2 is rotated in the direction of releasing the brake,
One working arm 37 of the spring 34 and the base side arm piece 28b
When the side surfaces of the working arm 37 are parallel to each other (the state shown in FIG. 6A), the middle part of the operating arm 37 faces the slope 54 from above, and therefore Even if the tip of the working arm 37 were to displace downward at this point, the middle part of the working arm 37 is engaged with the upper edge of the slope 54, thereby preventing the tip from moving downward. be done.
When the brake body 22 is further rotated clockwise from such a state, the intermediate portion of the operating arm 37 faces the upper surface of the corner of the operating arm 28 from above, or is exposed to the upper surface of the corner. (It will be in the state shown by the two-dot chain line in FIG. 3.)

In the above embodiment, the slope is provided only on one brake body, but it goes without saying that it may be formed on the other brake body just in case.

Effects of the Invention As is clear from the above description, the tape cassette of the present invention has a tape supply reel and a tape take-up reel on which tape is wound, and notches formed in the lower flanges of each of the tape reels. It is equipped with a pair of brake bodies that engage to lock the rotation of the tape reel, a spring that biases the brake body to rotate toward the tape reel, and a release member that releases the brake by the brake body. The above-mentioned pair of brake bodies are provided approximately symmetrically, and each has a claw piece that removably engages with the tape reel, and a pivot piece that is rotatably fitted onto a pin that is integrally erected on the lower half of the tape cassette. It consists of an operating arm that is formed to protrude from a cylindrical base serving as a fulcrum and is bent into a substantially L-shape, with one end of the release member commonly abutting, and the ring-shaped portion in the middle of the spring is connected to the cassette case. A relatively small diameter part is fitted onto a narrow diameter part formed through a step on the upper part of the pin erected in the rear center, and is placed on the upper surface of the step, and extends linearly from both ends of the annular part. The distal end portions of the two long operating arms are engaged with engaging portions provided on the respective upper portions of the L-shaped operating arm base side arm pieces of the pair of brake bodies, and are positioned on the upper end surface of the operating arms. The vertical engagement surface of the engagement portion is a continuous surface with the wall surface of the L-shaped operating arm, and when the operating arm is in a braking state, the corner of the L-shaped bend extends to both ends of the spring. It is located on the front side of the cassette in the straight part, and when the brake is released, the corner part is rotated to the rear side of the cassette across the straight part of the spring,
The L-shaped corner of the operating arm of the brake body is provided with an engaging portion that extends linearly from the lower end of the ring-shaped portion of the spring and is engaged with the distal end of the operating arm. A slope is formed on a protrusion vertically protruding from the wall surface of the L-shaped operating arm that is continuous with the vertical engagement surface to push the spring upward toward the upper end surface of the operating arm on the side of the engagement section. Features.

Therefore, according to the present invention, even when the working arm of the spring that biases the brake body to rotate toward the tape reel side tries to displace downward, the tip of the working arm of the spring always remains in the predetermined engagement of the brake body. The state of being engaged with the joint can be maintained continuously. Therefore, when the brake body is rotated, the tip of the spring is pushed by the side of the brake body, thereby reducing the rotation range of the brake body. can be prevented. In addition, the present invention can obtain the above-mentioned stable operation by simply forming a slope on the corner of the operating arm of the brake body, so the shape does not become large or complicated, and the cost is also high. I have no fear.

Therefore, according to the tape cassette of the present invention, it is possible to provide a novel tape cassette equipped with a reel brake mechanism that allows stable operation with a simple structure.

Although the above-mentioned embodiment shows an example in which the present invention is applied to a tape cassette for a VTR, the present invention is applicable to a tape cassette used for other purposes, such as a tape cassette for audio, or a tape cassette for storing various data on a magnetic tape. The present invention can also be applied to tape cassettes for magnetic recording, as well as tape cassettes in which a tape member other than magnetic tape is wound around a tape reel and housed in a cassette case.

[Brief explanation of the drawing]

Fig. 1 is a plan view of essential parts showing an example of a reel brake mechanism in a conventional tape cassette, Figs. A partially cutaway plan view of the upper half, FIG. 3 is an enlarged plan view of essential parts of the brake mechanism, FIG. 4 is a sectional view taken along line A-A in FIG. 3, and FIG. 5 is a brake Partially exploded perspective view showing the mechanism enlarged, No. 6
Figures 6 and 7 show the operating process of the brake mechanism. Figures 6A and B are plan views of the main parts, Figures 7A and B are side views of the main parts, and Figure 8 is the slope formed on the brake body. It is a perspective view showing a modification of . Explanation of symbols, 1... Tape cassette, 3...
(1) Lower half, 5... Tape, 6... Tape supply reel, 7... Tape take-up reel, 14...
Lower flange (of 6), 15... Notch (formed in 14), 16... Lower flange (of 7), 1
7... Notch (formed in 16), 22, 22'
... Brake body, 23, 23' ... Cylindrical base,
24, 24'...pin (installed at 3), 25,
25'... (brake body) claw piece, 28, 28'...
... (Brake body) operating arm, 28b, 28b'...
Base side arm piece (of the brake body operating arm), 30,3
0'... (brake body operating arm) engaging portion, 32,
32'... (28, 28') protrusion or corner, 33
... Slanted surface, 34 ... Spring, 35 ... (34) ring-shaped part, 36 ... (1 rear centrally installed) pin, 36a ... (36) step, 36b ... (3
(6) upper part) narrow diameter part, 37, 38... (34) working arm, 43... release member, 54... slope.

Claims (1)

[Claims for Utility Model Registration] A tape supply reel and a tape take-up reel on which the tape is wound, and a pair of reels that engage with notches formed in the lower flanges of each of the tape reels to lock the rotation of the tape reel. a brake body, a spring for rotationally biasing the brake body toward the tape reel, and a release member for releasing the brake by the brake body, and the pair of brake bodies are arranged substantially symmetrically. The tape cassette has a claw piece that removably engages with the tape reel, and a cylindrical base that serves as a pivot that is rotatably fitted onto a pin that is integrally erected on the lower half of the tape cassette. and an operating arm which is bent into a substantially L-shape and commonly abuts one end of the release member. The distal ends of two relatively long working arms that are fitted onto the narrow diameter part formed through the annular part and placed on the upper surface of the stepped part, and that extend linearly from both ends of the annular part, It is engaged with an engaging part provided on the upper part of each of the L-shaped operating arm base side arm pieces of the brake body and is located on the upper end surface of the operating arm, and the engaging part is vertically engaged. The surface is continuous with the wall surface of the L-shaped operating arm, and when the operating arm is in a braking state, the corner of the L-shaped bend is located in front of the cassette of the straight part extending to both ends of the spring, and the operating arm is in a braking state. In the released state, the corner portion is rotated toward the rear of the cassette across the linear portion of the spring, and at least the tip of the operating arm extending linearly from the lower end of the ring portion of the spring is engaged. At the L-shaped bent corner of the operating arm of the brake body where the joint is provided, a spring is attached to a protrusion vertically protruding from the wall surface of the L-shaped operating arm that is continuous with the vertical engagement surface. A tape cassette characterized in that a slope is formed that pushes up toward the upper end surface of the operating arm on the side of the upper engagement portion.