JPH0722732Y2 - Magnetic head support structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICABILITY The present invention is a magnetic head recording / reproducing apparatus capable of recording / reproducing in both forward and reverse directions, which is preferably implemented in a magnetic tape recording / reproducing apparatus. Regarding the structure.

2. Description of the Related Art In a magnetic tape recording / reproducing apparatus, it is necessary to arrange a magnetic head so that a gear head of the magnetic head is perpendicular to a running direction of the magnetic tape. That is, as shown in FIG. 4 (1), the minimum recording length Δ1 of the magnetized pattern in the state where the gear 4 of the magnetic head 3 intersects perpendicularly to the running direction 2 of the magnetic tape 1.
Corresponds to the distance between the gears 4.

On the other hand, as shown in FIG. 4B, when the gear 4 of the magnetic head 3 is inclined by an angle θ from the direction perpendicular to the running direction 2, the magnetization formed on the magnetic tape 1 is increased. The minimum recording length Δ2 of the pattern becomes longer than the length Δ1.

Therefore, when the gear cap 4 of the magnetic head 3 is inclined in this way, the apparent gear cap width becomes wider than the actual gear cap width, and the frequency characteristics in the high frequency range are deteriorated, and the reproduction output is increased. There is a problem that the level will decrease.

For this reason, in a typical prior art, the magnetic head 3 is attached to a base so that the gear 4 of the magnetic head 3 is perpendicular to the normal reproducing direction of the magnetic tape 1, for example, the arrow 2 direction.

However, in this prior art, when the magnetic tape 1 is run in the direction opposite to the arrow 2, due to variations in the components of the tape running system such as the pinch roller and the capstan, for example, the reference numeral θ. As described above, the azimuth angle indicated by is generated, which deteriorates the frequency characteristics in the high frequency range and lowers the reproduction output level as described above.

In another prior art for solving this problem, the first tape switching system is switched to either the forward or reverse running direction.
A cam member that interlocks with the lever member is provided, and by this angular displacement of the cam member, a screw for adjusting the inclination angle of the base to which the magnetic head is attached selectively contacts the cam member, In this way, even in either forward or reverse running direction,
A gear head of the magnetic head is configured to support the magnetic head so as to be perpendicular to the traveling direction of the magnetic tape.

In such a structure, a locking hole is formed in the first lever member, and a projection provided at one end of the second lever member is locked in the locking hole. A long hole is formed at the other end of the lever member. A projection vertically provided on a drive gear to which a driving force from a motor or the like is transmitted is engaged with the elongated hole, so that the rotational movement of the drive gear is switched between the traveling directions of the magnetic tape and the cam member is angled. It is possible to convert and transmit the linear reciprocating motion of the second lever member for displacement.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the above-described conventional technology, in order to realize smooth operation and absorb errors and variations of each component, the gear has a dead point at the protrusion engaged with the elongated hole. It is configured to stop in a state of slightly passing through. Correspondingly, the locking hole of the first lever member that locks the protrusion provided upright on the second lever member is formed to be slightly larger than the protrusion so as to have so-called play.

Therefore, when the magnetic tape reproducing apparatus configured as described above is used in an environment with a lot of vibration such as an automobile, the play causes rattling of the first lever member. As a result, the azimuth angle of the magnetic head supported by the cam member is deviated, and the above-mentioned problems occur.

To solve this problem, in the cam member, for example, a locking pin is provided on the base side so as to project / retract, and the locking pin is spring-loaded by a spring member in a direction projecting from the cam member toward the base side. Keep urging. Correspondingly, the base has a position where the locking pin is located when the magnetic tape is running in the forward direction and a position where the locking pin is located when the magnetic tape is running in the opposite direction. A tapered locking recess is provided in each of and. With this structure, when the angular displacement of the cam member by the first lever member is completed, the locking pin is fitted into the locking recess, which causes the rattling of the cam member as described above. Methods to prevent it are possible.

However, in such a structure, the cam member tends to float from the base due to the spring biasing of the locking pin, and this lift may cause new rattling. Moreover, the structure becomes complicated.

The purpose of the present invention is to make it possible to switch the magnetic head so that the azimuth angle of the magnetic head is in an optimum state according to the traveling direction of the magnetic tape with a simple structure, and to ensure the magnetic head in that switched state. The purpose of the present invention is to provide a support structure for a magnetic head that can be supported by a magnetic head.

Means for Solving the Problems The present invention provides a structure for running a magnetic tape in both forward and backward directions and supporting a magnetic head for performing at least reproduction of the magnetic tape, wherein the magnetic head is attached and A supporting member whose part is swingably supported by the base, a cam member supporting the other end of the supporting member so that the other end of the supporting member can be moved toward and away from the base, and a support member on the opposite side of the base. A lever member that is arranged and displaced in accordance with the running direction of the magnetic tape, and an eccentric erection on the base side of the cam member that is inserted up through an insertion hole formed in the base to lock the lever member. A protrusion that is locked to the inner peripheral surface of the hole; and a spring member that elastically biases the lever member in the displacement direction of the lever member, and when the lever member is not performing the displacement operation, Due to the elastic force of the spring member, the protrusion is The magnetic head support structure is characterized in that it is sandwiched by the inner peripheral surface of the locking hole of the lever member and the inner peripheral surface of the insertion hole of the base, and the displacement of the cam member is prevented. .

According to the present invention, one end of the support member to which the magnetic head is attached is swingably supported by the base, and the other end of the support head can be moved toward and away from the base by the cam member. Supported, and thus the azimuth angle to the magnetic tape can be varied. A protrusion is eccentrically provided upright on the base side of the cam member, and the protrusion is inserted into an insertion hole formed in the base and locked to the inner peripheral surface of the locking hole of the lever member. The lever member is displaced corresponding to the running direction of the magnetic tape, and the lever member is elastically biased in the displacement direction by the spring member.

Therefore, when the lever member is not performing the displacement operation, the lever member is elastically biased in the displacement direction by the spring member, whereby the protrusion of the cam member is caused to move. The cam member is sandwiched between the inner peripheral surface of the locking hole of the member and the inner peripheral surface of the insertion hole of the base, and the cam member is locked at the predetermined angular displacement position without rattling. Therefore, the change in the azimuth angle of the magnetic head, which changes due to the angular displacement of the cam member, can be suppressed, and the magnetic head can be switched so as to have the optimum azimuth angle corresponding to each traveling direction of the magnetic tape. Can be held.

Embodiment FIG. 1 is a plan view of a magnetic tape reproducing apparatus 21 according to an embodiment of the present invention in the vicinity of a magnetic head 22, and FIG. 2 is a sectional view taken along section line II-II of FIG. . The magnetic head 22 is provided with screws 24 near the central portion 23a of the support member 23 having a long plate shape.
It is screwed by. One end 23b of the support member 23,
A screw 26 inserted through the spacer 25 is screwed to the base 27, so that the support member 23 is swingably supported with the screw 26 as a fulcrum.

At one end 23b of the support member 23, a support protrusion 28 is formed on the surface on the base 27 side, and one end of the support member 28 is formed in an L-shape closer to the central portion 23a than the support protrusion 28. The other end of the leaf spring 29, which is sandwiched and supported by the spacer 25 and the screw 26, is in contact with the other end 23c of the support member 23. Spring biased.

The other end portion 23c of the support member 23 is formed by bending in a crank shape, and adjusting screws 31, 32 for adjusting the azimuth angle of the magnetic head 22 are screwed to the other end portion 23c. Either one of these adjusting screws 31 or 32 comes into contact with the projection 35 formed on the cam member 34 via the interposition member 33. The interposition member 33 is composed of a leaf spring formed in a substantially L shape, one end of which is swingably attached to the other end 23c of the support member 23, and the other end thereof is adjusted by the adjusting screw 31 as described above. Alternatively, it is interposed between 32 and the projection 35 of the cam member 34.

The cam member 34 is formed by the rotating shaft 36 that is erected on the base 27.
It is supported so as to be angularly displaceable around the axis of the rotary shaft 36. On the surface of the cam member 34 on the base 27 side, a locking projection 37 is erected eccentrically from the rotary shaft 36. This locking protrusion 37
Insertion hole 39 formed by communicating the base 27 and chassis 38
Through, and is locked to the inner peripheral surface of the locking hole 42 formed in the slide lever 41.

The slide lever 41 is formed in a substantially trapezoidal shape, and a locking hole 45 into which a locking protrusion 44 erected at one end of a switching lever 43 for switching channels is loosely inserted is formed in the center thereof. A long hole 46 is formed at the other end of the switching lever 43, and a locking protrusion 48 erected on a gear 47 is fitted into the long hole 46. The gear 47 is rotationally driven bidirectionally by a drive gear 49 attached to the output shaft of the motor or the like.

A contact piece 50 is formed on the gear 47, and a magnetic tape
When the traveling direction switching operation of 51 is not performed, the lock lever 52 extends in the direction of the arrow 53, and the abutment piece 50 is fitted into the lock lever 52, which prevents the rotation of the gear 47. It When the running direction of the magnetic tape 51 is reversed, the lock lever 52 retracts in the direction opposite to the direction of the arrow 53, whereby the gear 47 is rotationally driven by the drive gear 49.

The switching lever 43 is swingably supported by a support shaft 54, and thus the rotation of the gear 47 causes the gear 47 to rotate.
The locking projection 48 of is displaced in the long hole 46 of the switching lever 43,
As a result, the locking protrusion 44 of the switching lever 43 can displace the slide lever 41 in parallel with the running directions 55 and 56 of the magnetic tape 51.

A pair of capstans 61 and pinch rollers 62 are provided on the downstream side of the magnetic head 22 in the traveling direction 55, and a pair of capstans 63 and pinch rollers are provided on the downstream side of the traveling direction 56.
64 and are provided. The pinch rollers 62 and 64 are rotatably supported by holders 65 and 66, respectively.
5,66 are spring-biased in the directions of the capstan 61,63 around the support shafts 69,70 by springs 67,68.

In the holders 65 and 66, the slope 41 of the slide lever 41
Abutting surfaces 65a and 66a are formed on the surfaces facing a and 41b, respectively, and when the slide lever 41 is displaced in the traveling direction 55 side, the abutting surface 65a is slidably contacted with the slope 41a, Therefore, the holder 65 is displaced against the elastic force of the spring 67, and the pinch roller 62 separates from the capstan 61. At this time, the holder 66 is displaced by the elastic force of the spring 68, and the pinch roller 64 is pressed against the capstan 63 via the magnetic tape 51.

On the other hand, when the slide lever 41 is displaced in the traveling direction 56 side, the inclined surface 41b slides on the contact surface 66a of the holder 66, whereby the holder 66 is displaced against the elastic force of the spring 68. Then, the pinch roller 64 separates from the capstan 63. At this time, the holder 65 is displaced by the elastic force of the spring 67, and the pinch roller 62 comes into pressure contact with the capstan 61 via the magnetic tape 51.

One end of the spring 71 is fixed near the center of the slide lever 41, and the other end of the spring 71 is fixed to a fixed position such as the base 27. This spring 71 biases the slide lever 41 in a direction in which the slide lever 41 is maintained in a state where the slide lever 41 is not driven to be displaced.

FIG. 3 shows a magnetic tape reproducing apparatus configured as described above.
FIG. 6 is a plan view showing a simplified vicinity of a slide lever 41 for explaining a switching operation of a traveling direction of a magnetic tape 51 of 21. When the magnetic tape 51 is run in the running direction 55 side, that is, in the forward direction, the slide lever 41 moves through the gear 47, the switching lever 43, etc., as shown in FIG. Therefore, as described above, the pinch roller 62 on the downstream side in the traveling direction of the magnetic tape 51 is pressed against the capstan 61 via the magnetic tape 51, and the pinch roller 64 on the upstream side in the traveling direction is Separated from Capstan 63. As a result, the cam member 34 is angularly displaced in the direction of the arrow 72, and the adjusting screw 31 abuts on the protrusion 35 via the interposition member 33, as shown in FIG. In this way, the magnetic head 22 can be supported so that the azimuth angle is optimum for traveling the magnetic tape 51 in the forward direction.

When the magnetic tape 51 is run in the running direction 56 side, that is, in the opposite direction, the slide lever 41 is displaced in the running direction 55 side as shown in FIG. 3B, whereby the pinch roller 64 is moved. The capstan 63 is pressed against the magnetic tape 51 and the pinch roller 62 is separated from the capstan 61. At this time, the cam member 34 is angularly displaced in the direction opposite to the direction of the arrow 72, and the protrusion 35 is brought into contact with the adjusting screw 32 (see FIG. 2) via the interposition member 33. Thus the magnetic tape 51
The magnetic head 22 can be supported so that the azimuth angle is optimal for traveling in the opposite direction.

In the above description, the case where the adjustment screw 32 having a larger azimuth angle is switched to the adjustment screw 31 having a smaller azimuth angle has been described, but the intervening member 33 can smoothly perform the reverse operation.

As described above, in the steady state after the switching operation of the traveling direction of the magnetic tape 51 is performed, when the magnetic tape 51 is traveling in the forward direction shown in FIG. 3 (1),
The spring 71 elastically urges the slide lever 41 toward the traveling direction 56, whereby the surface 42a of the locking hole 42 of the slide lever 41 on the magnetic head 22 side and the base and chassis 38 are formed. The engaging projection 37 of the cam member 34 is clamped by the surface 39a of the insertion hole 39 opposite to the magnetic head 22, and thereby the cam member 34 is held without rattling and vibrating. As a result, the problem that the azimuth angle of the magnetic head 22 changes can be prevented.

Similarly, as shown in FIG. 3 (2), when the magnetic tape 51 is traveling in the reverse direction, the slide lever 41 is displaced toward the traveling direction 55 side, and the spring 71 is moved to the slide lever.
41 is elastically biased toward the running direction 55 side. Thus, the surface 42b of the locking hole 42 of the slide lever 41 opposite to the magnetic head 22 and the surface 39b of the insertion hole 39 on the magnetic head 22 side allow the locking projection 37 of the cam member 34 to move. Is pinched, and the azimuth angle of the magnetic head 22 is prevented from being displaced.

As described above, in the magnetic tape reproducing apparatus 21 according to the present invention, the locking projection 44 of the switching lever 43 has a simple structure using the spring 71.
And rattling due to play with the locking hole 45 of the slide lever 41 can be prevented, the angular displacement of the cam member 34 can be prevented, and the magnetic head 22 can be optimized for each traveling direction of the magnetic tape 51. It can be held at an azimuth angle. Further, the vibration resistance is improved, and it can be suitably implemented for vehicle use.

As described above, according to the present invention, the lever member, which is displaced according to the traveling direction of the magnetic tape, is elastically biased in the displacement direction by the spring member. In the cam member that changes the inclination angle of the support member to which the head is attached, the projection of the cam member is clamped by the inner peripheral surface of the locking hole of the lever member and the inner peripheral surface of the insertion hole of the base. Thus, it is locked without rattling at a predetermined angular displacement position. Therefore, the change in the azimuth angle of the magnetic head, which changes due to the angular displacement of the cam member, is suppressed, and the magnetic head is switched and held so as to have the optimum azimuth angle corresponding to each traveling direction of the magnetic tape. can do.

[Brief description of drawings]

FIG. 1 is a plan view of a magnetic tape reproducing apparatus 21 according to an embodiment of the present invention in the vicinity of a magnetic head 22, and FIG. 2 is a section line II of FIG.
-II is a sectional view, FIG. 3 is a plan view showing in simplified form the vicinity of the slide lever 41 for explaining the switching operation of the running direction of the magnetic tape 51, and FIG. 4 explains the problems of the prior art. 3 is a diagram showing the relationship between the magnetic tape 1 and the magnetic head 3 for the purpose of FIG. 21 …… Magnetic tape player, 22 …… Magnetic head, 23 ……
Supporting member, 27 ... Base, 29 ... Leaf spring, 31, 32 ... Adjusting screw, 33 ... Interposing member, 34 ... Cam member, 35 ... Projection,
37,44,48 …… Locking protrusion, 38 …… Cash, 39 …… Insertion hole, 41 …… Slide lever, 42,45 …… Locking hole, 43 ……
Switching lever, 47 ... Gear, 49 ... Drive gear, 51 ... Magnetic tape, 61, 63 ... Capstan, 62, 64 ... Pinch roller, 67, 68, 71 ... Spring

Claims (1)

[Scope of utility model registration request] 1. A structure for supporting a magnetic head for running a magnetic tape bidirectionally and for reproducing at least the magnetic tape, wherein the magnetic head is attached and one end thereof is rocked on a base. A support member that is movably supported; a cam member that supports the other end of the support member so that the other end of the support member can move toward and away from the base; A lever member that is displaced in accordance with the traveling direction, and an eccentric erection on the base side of the cam member. The lever member is inserted through an insertion hole formed in the base to the inner peripheral surface of the locking hole of the lever member. A protrusion that is locked, and a spring member that elastically biases the lever member in the displacement direction of the lever member, and when the lever member is not performing the displacement operation, the spring member elastically According to the purpose, the protrusion is a locking hole of the lever member. It is the inner peripheral surface and with One Manzanillo the inner peripheral surface clamping of the base of the insertion hole, the support structure of a magnetic head, characterized in that the displacement of the cam member is prevented.