JPH04241284A - Tape cartridge - Google Patents

Abstract

PURPOSE:To improve reliability on the operation of a reel lock mechanism by eliminating such malfunction as an operation cam is decanted in a guide boss or the boss is bitten by the cam which is guided by the guide boss, in the reel lock mechanism whose lock is released by the operation cam by which a pair of lock levers are slid up and down. CONSTITUTION:Against a lock releasing pin 24 whose head 26 is formed in a semispherical shape, in the bottom face of the operation cam 9 which is abutted on the pin, a recessed part 27, which corrects deviation and is abutted on the pin head 26 at 3 places or more under a normal abutting condition, is provided, and a component force toward correcting a posture is applied to the deviation correcting recessed part 27 at the time of abutting.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape cartridge equipped with a reel lock mechanism that prevents the tape reel from rotating freely when the tape reel is not in use.

0002

[Prior Art] In a reel lock mechanism, a pair of lock levers corresponding to each tape reel are arranged adjacently,
An operating lever that swings in response to the movement of the lock release pin.
VH is a form in which a pair of lock levers are released at the same time.
Used in S-type tape cartridges. In place of the above-mentioned operating lever, an improved reel lock mechanism is also disclosed in which an operating cam that moves up and down along with the lock release pin is used to simultaneously release a pair of lock levers, as disclosed in, for example, Japanese Patent Laid-Open No. 1-166386. It is publicly known.

In the improved reel lock mechanism, as shown in the attached FIG. 2, an operating cam 9 is guided and supported by a guide boss 8 so as to be able to move only vertically, and a cam piece 1 is provided at one location on the circumference of the operating cam 9.
5 is provided protrudingly. A passive rib 21 of the lock lever 11 is always located above the cam piece 15, and when the operating cam 9 moves upward, the cam piece 15 pushes out the passive rib 21 and the entire lock lever 11 swings in the unlocking direction. move. In the unused state shown in FIG.
At 0, it is pushed down to the position where it touches the inner bottom of the case,
When the lock release pin 24 enters into the guide boss 8, it is pushed up against the spring 10.

0004

[Problems to be Solved by the Invention] In the conventional reel lock mechanism described above, the pin head 26 is formed into a hemispherical shape in order to smoothly insert the lock release pin 24 into the guide boss 8. . Further, the bottom surface of the operating cam 9 that comes into contact with the pin head 26 was a flat end surface, and the two were in point contact. Therefore, if the center of the lock release pin 24 and the center of the operating cam 9 deviate even slightly, a tilting moment acts on the operating cam 9, causing the entire cam to be tilted by the clearance with the guide boss 8.

[0005] When the operation cam 9 moves up and down in a tilted state,
Sliding resistance against the guide boss 8 increases, and a large operating force is required to release the lock. Depending on the direction of inclination, the unlocking operations of the left and right lock levers 11 may differ. In rare cases, a part of the guide boss 8 may be bent and deformed, and in this case, even if the lock release pin 24 is retracted outside the case, the operating cam 9 remains stuck near the upper end of the guide boss 8. This results in a situation where the lock lever 11 cannot be returned to the locked position.

An object of the present invention is to enable the operating cam itself to absorb the misalignment of the operating cam with respect to the lock release pin, or to correct the tilting of the operating cam due to the misaligned center, thereby ensuring smooth vertical movement of the operating cam. This improves the reliability of the reel lock mechanism.

[0007]

[Means for Solving the Problems] The tape cartridge of the present invention has a guide boss 8 that opens at the bottom of the main case 1 at the center of the triangular adjacent portion between the left and right tape reels 3.
A lock lever 11 is provided between the guide boss 8 and each tape reel 3, and is supported so as to be swingable in the horizontal direction and engages and disengages from the engagement teeth 23 on the periphery of the reel flange.
11, the lock levers 11, 11 are urged to move to the locked position by springs 12, and the operating cam 9, which is pushed up by the lock release pin 24, is guided by the guide boss 8 so as to be vertically movable. supported and operated cam 9
is urged downward by a spring 10, a cam surface 18 for unlocking the lock lever 11 is provided at one location on the circumferential surface of the operation cam 9, and the hemispherical shape of the lock release pin 24 It is required that the bottom surface of the operating cam 9 that contacts the pin head 26 be formed with misalignment correction recesses 27 that contact the pin head 26 at three or more places in the normal contact state. The misalignment correction recess 27 is located at the pin head 26.
It can be made of a partial spherical surface formed with a spherical radius r that is equal to or smaller than the spherical radius R of . Furthermore, the misalignment correction recess 27 can be formed in a conical shape. Furthermore, the misalignment correction recess 27 can be formed to have an opening shape of a regular polygon including a circle, and the misalignment correction recess 27 can be set to have a cross-sectional shape in which the opening periphery 28 comes into contact with the pin head 26 first. can.

[0008]

[Operation] A misalignment correcting recess 27 that contacts the pin head 26 of the lock release pin 24 is provided on the bottom surface of the operating cam 9, and this recess 27 contacts the pin head 26 at at least three places. If there is a misalignment between the pin center and the cam center, the pin head 2 will be removed from the opening periphery 28 of the misalignment correction recess 27.
A component force in a direction to eliminate the center deviation is applied to the portion where the cam 6 is hit in advance, and this lateral component force moves the operating cam 9 laterally within the clearance range to absorb the center deviation. When the operating cam 9 is tilted, the opening periphery 28 of the misalignment correction recess 27 comes into contact with the pin head 26 at a position close to the top and at a position away from the top. At this time, the downward force exerted by the spring 10 becomes larger as the position is closer to the top. In other words, a large downward force in the direction of correcting the tilted posture is applied to the abutment position on the upper side of the inclination. It is in contact with 26.

[0009]

[Effects of the Invention] According to the tape cartridge of the present invention,
By providing the misalignment correction recess 27 on the bottom surface of the operating cam 9, the operating cam 9 itself can move laterally to absorb center misalignment and exhibit an alignment function, and when the operating cam 9 is tilted, the misalignment The posture of the operating cam 9 is corrected by the downward force acting on the opening periphery 28 of the correction recess 27 so as to return it to its proper state. Therefore, the operating force of the operating cam 9 is increased or the operation cam 9 is prevented from getting caught in the guide boss 8, and the operating cam 9 can always be smoothly moved up and down, thereby improving the reliability of the reel lock mechanism. In particular, when the misalignment correction recess 27 is formed with a partially spherical surface, there is an advantage that misalignment absorption and tilting posture correction effects can be obtained in all directions in the circumferential direction without any directivity.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 to 7 show an embodiment of a tape cartridge according to the present invention. In FIG. 6, reference numeral 1 denotes a main body case formed by joining upper and lower plastic cases 1a and 1b with their lids together. Tape reels 3 on which the tape 2 is wound are arranged on the left and right sides inside the main body case 1. The tape 2 pulled out from one tape reel 3 is wound onto the other tape reel 3 via tape guides 4 provided on the left and right sides of the front surface of the case. A tape loading pocket 5 is recessed between the left and right tape guides 4. A front cover 6 for protecting the tape is disposed to cover the front and upper surfaces of the pocket 5, and is supported with respect to the main body case 1 so as to be swingable up and down to open and close.

A reel lock mechanism is provided in a triangular area surrounded by the inner back wall of the pocket 5 and the left and right tape reels 3, 3 to prevent rotation of both reels 3, 3 when not in use. In FIG. 2, the reel lock mechanism includes a guide boss 8 provided near the center of the area, an operating cam 9 and a spring 10 fitted into the boss 8, and a space between the guide boss 8 and each tape reel 3. Lock lever 11 placed in
- Constructed using 11 and spring 12 as element members.

The guide boss 8 has a basic shape of a cylindrical wall with a circular cross section that opens at the bottom of the lower case 1b, and the cylindrical wall is divided at two places on the left and right by vertical grooves 13, 13, and the rear wall is cut out. Each partial cylinder wall consists of lower case 1.
It is erected from b. As will be described later, the vertical groove 13 also serves as a light projection window for tape end detection. As shown in FIG. 1, bosses 8a are provided on the inner surface of the upper case 1a so as to protrude corresponding to each partial cylinder wall.

The operation cam 9 is formed into a cylindrical shape that opens upward, and has a wedge-shaped cam piece 15 at the front center of its circumferential surface.
, horizontal pawls 16 are formed protruding from both sides of the lower end of the circumferential surface, and a spring receiving boss 17 is protruded from the bottom of the cylinder. A cam surface 18 for unlocking the lock lever 11 is formed on the cam piece 15 as a flat end surface with an upward slope starting from its lower part. This operating cam 9 is fitted into the guide boss 8 from above, and by engaging its horizontal claws 16 with the vertical grooves 13, the entire guide boss 8 is unrotatable.
It can move up and down along. In the installed state, the operation cam 9
A compression coil type spring 10 is interposed between the upper case 1a and the upper case 1a, and this spring 10 pushes down and biases the operating cam 9.

In FIG. 7, the lock lever 11 has an L-shaped lock claw 20 projecting from the circumferential surface of a proximal end boss 19, and a passive rib 21 protruding along the flat end wall of the proximal end boss 19. It will be done. By pivotally supporting the base end boss 19 with a pin 22 provided upright on the lower case 1b, the entire lock lever 11 can be horizontally swung against the engagement teeth 23 provided on the periphery of the lower reel flange of the tape reel 3. The lock pawl 20 engages and disengages. In order to bias this lock lever 11 into lock,
It has a torsion coil spring 12. As shown in FIG. 3, the spring 12 has a spring arm 12a projecting from a coil portion externally fitted onto the left and right pins 22, and hooks the spring arm 12a onto each lock pawl 20.

As shown in FIG. 1, when the lock lever 11 is in the locked position, the lower end of the driven rib 21 is positioned near the upper end of the cam surface 18 of the operating cam 9 with a very small gap. From this state, when the operating cam 9 is pushed up with the lock release pin 24, the passive rib 21 comes into contact with the cam surface 18 and receives the operating force from the cam surface 18 toward the front of the case, so that the entire lock lever 11 is moved by the spring 12. It swings in the unlocking direction against the This oscillation is caused by the operation cam 9
The process is completed when the cam surface 18 rises by the vertical length of the cam surface 18, that is, at the beginning of the rise, and this state is maintained thereafter. Therefore, the passive rib 21 extends to the upper end of the base end boss 19, so that it can be received by the cam piece 15 even when the operating cam 9 is at the uppermost position (see FIG. 3).

A light source 25 (see FIG. 1) for optically detecting the tape end is incorporated in the lock release pin 24, and the detection light is emitted to the left and right sides through the vertical groove 13 of the guide boss 8. irradiate. At this time, since it is necessary to position the light source 25 almost at the center of the main body case 1, it is necessary to push the operating cam 9 up close to the upper case 1a. The pin head 26 of the lock release pin 24 is formed into a hemispherical shape to facilitate insertion into the guide boss 8.

When the operating cam 9 is pushed up with the lock release pin 24, the operating cam 9 is tilted to prevent serious malfunctions such as getting caught in the guide boss 8.
A misalignment correction recess 27 is provided on the bottom surface of the holder. As shown in FIG. 4, the misalignment correction recess 27 is formed of a partially spherical surface, and is set to have a spherical radius r slightly smaller than the spherical radius R of the pin head 26. Naturally, the shape of the opening periphery 28 of the misalignment correction recess 27 at this time is circular, but in order to optimize the depth of the misalignment correction recess 27, two locations of the opposing opening periphery 28 and the center of the spherical radius are connected. The sandwiching angle θ is set to 53 to 56 degrees.

When the above-mentioned misalignment correction recess 27 is in a normal state in which its center coincides with the center of the lock release pin 24, the entire opening periphery 28 comes into contact with the pin head 26. In other words, it touches in countless places. However, if there is a deviation between the two centers, Figure 4
As shown in FIG. 2, one part of the periphery of the opening periphery 28 comes into contact with the pin head 26 before the other. In this state, a lateral component force f acts on the abutment location. Therefore, the entire operating cam 9 can absorb the shift by sliding sideways toward the side that eliminates the center shift. However, this absorption range does not exceed the clearance range between the operating cam 9 and the guide boss 8. In FIG. 4, reference numeral F is a force that is applied to the abutting portion by the pushing force of the lock release pin 24.

Depending on the magnitude of the center deviation and the inclination of the tape cartridge loading position, the operating cam 9 may be temporarily tilted relative to the pin head 26 as shown in FIG. At this time, the pin head 2 is attached to the abutment area of the opening periphery 28.
A position near the top of 6 and a position away from the top occur. Comparing the downward component forces g1 and g2 due to the depressing force G of the spring 10 at both positions, the downward component force g1 at the position near the top is definitely larger. Therefore, the operation cam 9 has
The component force g1 in the direction of returning the tilted posture to its original state acts strongly, and the tilted posture can be corrected.

FIGS. 8 to 11 show another embodiment of the misalignment correction recess 27. FIG. In FIG. 8, the misalignment correction recess 27 is formed into a conical shape. In FIG. 9, the misalignment correction recess 27 is formed in the shape of a square pyramid. In FIG. 10, the misalignment correction recess 27 has a shallow rectangular parallelepiped shape, and its opening shape is square. In Figure 11,
The misalignment correction recess 27 is formed as a groove that intersects in a criss-cross pattern, and the four abutting portions 29 of the intersecting portion abut against the pin head 26.

[Brief explanation of the drawing]

FIG. 1 is a sectional view taken along line A-A in FIG. 2 showing a reel lock mechanism.

FIG. 2 is a plan view of essential parts showing a locked state of the reel lock mechanism.

FIG. 3 is a plan view of essential parts showing the reel lock mechanism in an unlocked state.

FIG. 4 is an explanatory diagram showing the misalignment correcting action of the operating cam.

FIG. 5 is an explanatory diagram showing the tilt correction action of the operating cam.

FIG. 6 is a conceptual explanatory diagram showing an outline of a tape cartridge.

FIG. 7 is a perspective view of the reel lock mechanism.

FIG. 8 is a perspective view showing another embodiment of the misalignment correction recess.

FIG. 9 is a perspective view showing another embodiment of the misalignment correction recess.

FIG. 10 is a longitudinal sectional view showing another embodiment of the misalignment correction recess.

FIG. 11 is a bottom view showing another embodiment of the misalignment correction recess.

[Explanation of symbols]

8 Guide boss 9 Operation cam 10 Spring 11 Lock lever 12 Spring 18 Cam surface 23 Engaging teeth 24 Lock release pin 26 Pin head 27 Misalignment correction recess 28 Opening periphery

Claims (4)

[Claims] 1. A guide boss 8 that opens at the bottom of the main body case 1 is provided at the center of the triangular adjacent area between the left and right tape reels 3 , and the guide boss 8 and each tape reel 3 are connected to each other.
A lock lever 11.1 is supported so as to be swingable in the horizontal direction between the lock lever 11 and the lock lever 11.
1 are provided respectively, the lock levers 11, 11 are urged to move to a locked position by a spring 12, and an operating cam 9 which is pushed up by a lock release pin 24 is guided and supported by the guide boss 8 so as to be movable up and down. The operating cam 9 is urged downward by a spring 10, and a cam surface 18 for unlocking the lock lever 11 is provided at one location on the circumferential surface of the operating cam 9. A tape cartridge in which a misalignment correcting recess 27 is formed on the bottom surface of the operating cam 9, which contacts the hemispherical pin head 26, and which contacts the pin head 26 at three or more places in a normal contact state. 2. The tape cartridge according to claim 1, wherein the misalignment correction recess 27 is formed of a partial spherical surface having a spherical radius r equal to or smaller than the spherical radius R of the pin head 26. 3. The tape cartridge according to claim 1, wherein the misalignment correction recess 27 is formed in the shape of a weight. 4. The misalignment correction recess 27 is formed in the opening shape of a regular polygon including a circle, and the misalignment correction recess 27 is set to have a cross-sectional shape such that the opening periphery 28 contacts the pin head 26 first. A tape cartridge according to claim 1, wherein the tape cartridge has: