JP3511739B2 - Head element height adjusting apparatus and magnetic tape recording and / or reproducing apparatus including the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video tape recorder (VTR), a digital audio tape recorder (R-DAT), or the like, in which an audio signal or a video signal is magnetically recorded on a recording track of a magnetic recording medium such as a magnetic tape. The present invention relates to a head element height adjusting device used for adjusting the position of a head element for recording or reproducing as a signal, and a magnetic tape recording and / or reproducing apparatus including the head element height adjusting device.

[0002]

2. Description of the Related Art Conventionally, a magnetic recording and / or reproducing apparatus such as a VTR or R-DAT which uses a magnetic recording medium such as a magnetic recording tape reads an information signal recorded on the magnetic recording tape or magnetically records the information signal. It has a head element for recording on the tape. The head element reads and reproduces an information signal from the signal recording surface of the magnetic recording medium and writes and records the information signal on the signal recording surface of the magnetic recording tape by the magnetic flux generated by the coil and the magnetic gap.

The head element includes a magnetic core formed by combining a pair of magnetic core halves forming a closed circuit, a magnetic gap that is a minute gap formed in the magnetic core, and a substantially continuous magnetic gap. It is composed of a rectangular winding guide hole. In the head element, winding guide grooves are provided on both side edges of the pair of magnetic core halves. In the head element, the coil is wound around the winding guide hole and the winding guide groove of the magnetic core half body.

Further, the magnetic core constituting the head element is
It is made of a magnetic material such as ferrite and serves as a passage for transmitting a magnetic flux from the coil to the magnetic recording medium at the time of recording and from the magnetic recording medium to the coil at the time of reproducing. The magnetic gap is
It serves to narrow the range of the spread of the magnetic field for recording an information signal on the magnetic recording medium, and serves as an inlet for the magnetic flux from the magnetic recording medium during reproduction.

The head element is attached to, for example, a drum type magnetic head device to record / reproduce information signals on / from a magnetic recording medium. A conventional drum-type magnetic head device is generally composed of an upper drum, a lower drum, and an intermediate drum rotatably provided between the upper drum and the lower drum via a rotary shaft. In the middle drum, a plurality of head elements are joined and fixed to the outer peripheral portion of the middle drum with their magnetic gaps facing each other.

In the drum type magnetic head device, the plurality of head elements rotate and move so that each magnetic gap records an information signal on the magnetic recording medium. At this time, the magnetic gap forms a recording track pattern on the magnetic recording medium.

The head element is accurately positioned by adjusting the position of the magnetic gap with respect to a magnetic recording medium such as a magnetic tape. Further, in order to record / reproduce information signals with high recording density on a magnetic tape, a drum-type magnetic head device in which a set of head elements is mounted side by side has a magnetic gap of a set of head elements relative to each other. Position adjustment is performed and each is positioned.

In the drum type magnetic head device, it is necessary to uniformly form a recording track pattern for recording an information signal on the magnetic recording medium. That is, in the drum type magnetic head device, the magnetic gap formed in the head element must be positioned with high accuracy. Therefore, in the drum type magnetic head device, a head element height adjusting device is used to adjust the position of the head element with respect to the middle drum to which the head element is attached (hereinafter referred to as the head element height). .

A conventional head element height adjusting device 40 will be described with reference to FIGS. The height adjusting device 40 of the head element is roughly composed of a first base 41 and a second base 42 which are attached to a head drum 51 in which a groove portion 51A opening to the outer peripheral portion is formed, and these first bases. A first support piece 43 and a second support piece 44, which are cantilevered on one ends of the base 41 and the second base 42, and free ends of the first support piece 43 and the second support piece 44. It is composed of a first head element 49 and a second head element 50 which are respectively joined and fixed to the section.

The head drum 51 to which the height adjusting device 40 of the head element is attached is formed in a bottomed cylindrical shape, and a groove portion 51A opening to the outer peripheral portion is provided as a recess. The head drum 51 has mounting holes 57A and 57B formed along the inner peripheral portion thereof.

The first base 41 and the second base 42 are formed of, for example, stainless steel or phosphor bronze in an arc-shaped plate material that can be elastically deformed, and fixing holes 56A and 56B are provided at one end thereof.
Are drilled respectively. The first support piece 43 and the second support piece 44 are formed in an arc-shaped plate material that can be elastically deformed by, for example, stainless steel or phosphor bronze, and one end of the first support piece 43 and the second support piece 44 are formed in a groove portion 51A formed in the head drum 51. Facing each other at corresponding positions, fixing holes 55A and 55B are formed at the other ends.

The support pieces 43, 44 are fixed in a fixing hole 55.
Fixing screws 45 and 46 are respectively screwed into A and 55B, and fixing holes 56 of the first base 41 and the second base 42 are fixed.
It is fixed to A and 56B respectively. That is, the first
The support piece 43 and the second support piece 44 of the first base 41
And cantilevered at one end of the second base 42.

Further, the first support piece 43 and the second support piece 44 are provided with a first adjustment screw mounting hole 54A near the free ends thereof.
And a second adjusting screw mounting hole 54B are provided respectively. The first adjusting screw 47 is provided in the first adjusting screw attaching hole 54A and the second adjusting screw attaching hole 54B.
The second adjusting screw 48 is provided at a position corresponding to the groove portion 51A provided in the head drum 51. These first adjusting screw 47 and second adjusting screw 4
8, each tip has a first base 41 and a second base 4
The two main surfaces are in contact with each other.

The first support element 43 and the second support element 44 have the first head element 49 and the second head element 50 at the free ends of their respective magnetic gaps G3 and G4 on the outer periphery. Are joined and fixed to each other.

In the head element height adjusting device 40 constructed as described above, the first head element 49 and the second head element
Of each magnetic gap G formed in the head element 48 of the
Regarding the operation of moving and adjusting the heights of 3 and G4,
This will be described with reference to FIG. Head element height adjusting device 4
With 0, as the first adjusting screw 47 and the second adjusting screw 48 are tightened, the tips of the adjusting screws 47 and 48 gradually protrude from the support pieces 43 and 44, respectively.

In the first base 41 and the second base 42, the tip ends of the adjusting screws 47 and 48 are the main surface portions because the first adjusting screw 47 and the second adjusting screw 48 respectively project. And is elastically deformed. Then, the support pieces 43 and 44 to which the head elements 49 and 50 are joined and fixed are
The movement is adjusted in the A direction shown in FIG.

That is, in the support pieces 43 and 44, the facing distance between the support pieces 43 and 44 and the bases 41 and 42 is adjusted. By screwing in the adjusting screw, the base 4
The free ends of the support pieces 43, 44 are pushed up in the A direction by the adjusting screws 47, 48 with the intersection of the abutting surface with the first and the second screws 42 and the axis of the fixing screws 45, 46 as a fulcrum.

Therefore, the support pieces 43 and 44 move the first head element 49 and the second head element 50, which are arranged and fixed to the pushed up free end, in the A direction. Therefore, the support pieces 43 and 44 move the heights of the magnetic gaps G3 and G4 formed in the head elements 49 and 50 in the A direction.

As described above, the conventional head element height adjusting device 40 adjusts the height of the magnetic gaps G3 and G4 for each of the first head element 49 and the second head element 50. A screw 47 and a second adjusting screw 48 are provided respectively, and the height is adjusted for each head element. That is, the positions of the head elements 49 and 50 in the height direction are positioned with respect to the main surfaces of the bases 41 and 42 of the head elements 49 and 50, respectively.

A head element height adjusting device 40
The first base 41 and the second base 42 are fixed to the head drum 51 having the groove 51A. Therefore, the head drum 51 is stressed by the adjusting screws 47 and 48 that adjust the positions of the head elements 49 and 50 in the height direction.

However, in the height adjusting device 40 of the head element, the first base 41 and the second base 42 formed on the elastically deformable arc-shaped plate member have their respective free ends. This is a so-called beam structure provided at a position corresponding to the groove portion 51 </ b> A recessed in the head drum 51.

Therefore, in the head element height adjusting device 40, the first base 41 and the second base 42 support the first head element 49 and the second head element 50, respectively. There is an advantage that the load due to the stress is not directly applied to the head drum 51. That is, the head element height adjusting device 40 has a function of interrupting the stress generated by supporting the head elements 49 and 50 without transmitting the stress to the head drum 51.

As described above, in the drum type magnetic head device, the respective magnetic gaps G3 and G4 are positioned with high precision in order to form a uniform recording track pattern. That is, the drum-type magnetic head device has a relative magnetic gap between the first head element and the second head element in order to reliably perform high recording density azimuth recording on the magnetic recording medium. It is necessary that no change occurs in the correct position.

[0024]

By the way, the height adjusting device 40 of the head element is subject to the first vibration due to external vibrations and shocks and environmental changes such as temperature changes.
The adjustment screw 45 and the second adjustment screw 46 may be slightly displaced such as loosened. The first head element 49 and the second head element 50, which are joined and fixed to the first support piece 43 and the second support piece 44, respectively, include adjustment screws 45 and 46.
A minute displacement occurs in the magnetic gap G3,
The height of G4 changes. Therefore, the head element 4
Nos. 9 and 50 cannot accurately follow the magnetic gaps G3 and G4 to the magnetic recording medium, and a uniform recording track pattern cannot be formed on the magnetic recording medium.

That is, the head element height adjusting device 40
Is the first head element 49 and the second head element 50.
, The first base 41 and the second base 42 are used as position references, respectively. For this purpose, the first head element 49
One of the first head element 49 and the second head element 50 is displaced by the displacement occurring in the first head element 49 or the second head element 50.
However, there is a problem in that the relative position of the head element 50 changes.

Therefore, according to the present invention, it is possible to reduce the occurrence of changes in the relative positions of the first head element and the second head element, and to improve the stability of the recording / reproducing operation against environmental changes. It is proposed for the purpose of providing a height adjusting device for a head element.

[0027]

In order to achieve the above-mentioned object, a height adjusting device for a head element according to the present invention is provided with an opening at an outer peripheral portion of a head drum formed in a cylindrical shape having a bottom and is recessed. Formed of elastically deformable plate material, both ends of which are fixed to the head drum so as to be hung over the groove, and each free end is recessed in the head drum. A first support piece and a second support piece whose fixed ends are cantilevered on the same base so as to face each other at positions corresponding to the groove portions,
The first support piece and the second support piece are attached near the free ends thereof, respectively, and the facing distance between the first support piece and the second support piece and the same base can be adjusted. A first adjusting screw and a second adjusting screw, and a first head element and a second head element which are respectively joined and fixed to free ends of the first supporting piece and the second supporting piece. The height of the first head element and the second head element facing the same base is adjusted by adjusting the first adjusting screw and the second adjusting screw. Characterize.

The base is formed in a semi-circular plate shape and is provided along the inner peripheral portion of the head drum having the recess.
Further, the base is folded back so that both ends thereof overlap with the base, and the first support piece and the second support piece are integrally formed. Alternatively, the first
The support piece and the second support piece each have a joining hole formed at each fixed end portion, and a joining portion integrally formed at both end portions of the same base is formed in the joining hole. By being inserted and crushing the tips of these joints, they are joined and fixed to both ends of the same base.

[0029]

According to the present invention, the head element height adjusting apparatus and the magnetic tape recording and / or the head height adjusting apparatus according to the present invention are constructed as described above.
Alternatively, the reproducing device adjusts the height of the first head element and the second head element facing the same base by adjusting the first adjusting screw and the second adjusting screw,
The change occurring in the relative position between the first head element joined and fixed to the support piece and the second head element joined and fixed to the second support piece is reduced.

[0030]

EXAMPLE A concrete example of the present invention will be described below with reference to FIG.
It will be described with reference to FIGS. The head element height adjusting device 1 according to the present invention has the same basic configuration as the conventional head element height adjusting device 40. The base 14 is attached to the head drum 15 shown in FIG. A first supporting piece 10 and a second supporting piece 11 that are cantilevered at both ends of the first and second supporting pieces 14, and a first supporting piece 10 and a second supporting piece 11 that are respectively supported by the first supporting piece 10 and the second supporting piece 11. It is composed of a head element 6 and a second head element 7.
Further, in the figure, a conventional head element height adjusting device 4
The same parts as 0 are designated by the same reference numerals.

As shown in FIGS. 1 to 3, the head element height adjusting device 1 includes a base 14 formed in a semi-circular plate shape.
A first support piece 10 and a second support piece 11, fixing screws 12 and 13 for fixing the first support piece 10 and the second support piece 11 and the base 14, respectively, and the support piece 10. ,
A first head element 6 and a second head element 7, which are respectively joined and fixed to the free ends of 11, and a first adjusting screw for adjusting the height of the first head element 6 and the second head element 7. 8 and a second adjusting screw 9.

First, the head drum 15 to which the height adjusting device 1 of the head element is attached is formed in a bottomed cylindrical shape, and a groove portion 15A opening to the outer peripheral portion is provided as a recess. The head drum 15 has mounting holes 24A and 24B formed along the inner peripheral portion thereof.

The base 14 is made of, for example, stainless steel or phosphor bronze, and is formed into a plate shape that is elastically deformable.
The base 14 is provided with fixing holes 22A and 22B at both ends, respectively, and is fixed to the first via the fixing screws 12 and 13.
The fixed end portions of the support piece 10 and the second support piece 11 are fixed. Further, the base 14 is attached to a groove portion 15A recessed in the head drum 15 and is attached to a mounting hole 24A formed in the head drum 15.
It is attached to 24B via fixing screws 12 and 13.

First support piece 10 and second support piece 11
Is made of stainless steel or phosphor bronze, for example, and is formed into a plate shape that is elastically deformable. These support pieces 10, 1
1 has fixing holes 21A and 21B formed at its fixed end, and an adjustment screw mounting hole 23A at its free end.
23B are provided respectively.

The free ends of these supporting pieces 10 and 11 face each other at positions corresponding to the groove portions 15A formed in the head drum 15, and fixing holes 21A are formed in the fixing ends. Fixing screws 12 and 13 are respectively screwed into 21B and fixed to the base 14 in a cantilevered manner. In addition, these support pieces 10, 11
The first adjusting screw 8 and the second adjusting screw 9 are respectively screwed into the adjusting screw mounting holes 23A and 23B at positions corresponding to the groove portion 15A provided in the head drum 15.

The first head element 6 and the second head element 7 are constructed by a pair of magnetic core halves constituting a closed circuit being butted against each other and joined together. Magnetic gaps G1 and G, which are minute gaps, are formed on the abutting surfaces of the magnetic core halves constituting the head elements 6 and 7.
2 is formed. Also, these head elements 6, 7
Is provided with a winding guide hole (not shown) communicating with the magnetic gaps G1 and G2, and the coils are wound around them. The head elements 6 and 7 are
Are fixed to the free ends of the supporting piece 10 and the second supporting piece 11 with the magnetic gaps G1 and G2 facing the outer peripheral portions.

The head element height adjusting device 1 is fixed to the head drum 15 with the magnetic gaps G1 and G2 formed in the head elements 6 and 7 protruding from the outer peripheral portions of the support pieces 10 and 11. There is. Then, the head element height adjusting device 1 tightens the first adjusting screw 8 and the second adjusting screw 9, respectively, so that the head elements 6 and 7 are tightened.
The positions of the magnetic gaps G1 and G2 formed at are adjusted.

The operation of the head element height adjusting apparatus 1 configured as described above for moving and adjusting the position of the magnetic gap will be described. Height adjusting device 1 for this head element
By tightening the first adjusting screw 8, the tip of the adjusting screw 8 gradually protrudes from the support piece 10,
The base 14 is elastically deformed by abutting on the main surface of the base 14. Therefore, the free end of the first support piece 10 is moved by the adjusting screw 8 in the direction A shown in FIG. 3 with the intersection of the abutment surface with the base 14 and the axis of the fixing screw 12 as a fulcrum. . Then, this head element height adjusting device 1
Moves the first head element 6 bonded and fixed to the free end of the support piece 10 as the free end of the support piece 10 moves in the A direction. Therefore, this head element 6
The height of the magnetic gap G1 formed at is adjusted in the A direction.

In the height adjusting device 1 for the head element, when the second adjusting screw 9 is tightened, the tip end of the adjusting screw 9 gradually projects from the support piece 11, and the base 1
The base 14 is elastically deformed by abutting on the main surface of No. 4.
Therefore, the free end of the second support piece 11 has the adjustment screw 9
3 is moved in the direction A shown in FIG. 3 with the intersection of the abutment surface with the base 14 and the axis of the fixing screw 13 as a fulcrum. The head element height adjusting device 1 includes a support piece 11
The second head element 7 joined and fixed to the free end of the support piece 11 is moved as the free end of the second head moves in the direction A. Therefore, the height of the magnetic gap G2 formed in the head element 7 is adjusted in the A direction.

The head element height adjusting device 1 is
Magnetic gaps G1 and G2 formed in the head elements 6 and 7
After the adjustment of the movement of the height of each is completed, the first adjusting screw 8 and the second adjusting screw 9 are fixed by a resin material such as epoxy resin to prevent them from loosening.

As described above, the head element height adjusting device 1 includes the first head element 6 and the second head element 7.
However, since the same base 14 is used as a positioning reference for each other, the first head element 6 or the second head element 7
Even if the position changes in either one of
In the first head element 6 and the second head element 7,
It is possible to reduce the occurrence of a change in the relative position.

Further, in the height adjusting device 1 of the head element, the base 14 is elastically deformed by the adjusting operation of the first adjusting screw 8 and the second adjusting screw 9, so that the base 14 is adjusted.
Reduces the stress that supports the first support piece 10 and the second support piece 11 and reduces the sensitivity of the adjusting operation. Therefore, the heights of the first magnetic head 6 and the second magnetic head 7 are slightly reduced. Adjustment can be easily performed.

Further, the head element height adjusting device 1 is
By changing the thickness dimensions of the support pieces 10 and 11 and the base 14, it is possible to appropriately adjust the respective elastic coefficients and easily adjust the displacement amount of the head element by the adjusting screw. Therefore, the relative amount of change between the first head element 6 and the second head element 7 can be made extremely small. That is, the head element height adjusting device 1
It is possible to improve the stability of the recording / reproducing operation.

In the height adjusting device 1 of the head element described above, both end portions of each of the first supporting piece 10 and the second supporting piece 11 are fixed to the base 14 to which the first supporting piece 10 and the second supporting piece 11 are fixed. Although it was fixed via the fixing screws 12 and 13, it is not limited to such a base 14 and can be developed to bases 16 and 17 described below. The same parts as those of the head element height adjusting device 1 are designated by the same reference numerals.

As shown in FIGS. 3 and 4, in the head element height adjusting device 2, both ends of a base 16 formed on an arc-shaped plate material of stainless steel or phosphor bronze are attached to the base 16. The first support piece 16A and the second support piece 16B are integrally formed by being folded back so as to overlap each other.

Further, as shown in FIGS. 5 and 6, the height adjusting device 3 for the head element has the joint portions 3 at both ends of the base 17.
2A and 32B are integrally formed to project. Further, the first support piece 10 and the second support piece 11 have fixing holes 21A and 21B formed at their fixed ends, respectively.
The fixing portions 21A and 21B are connected to the joint portions 32A and 32, respectively.
B is inserted respectively. Then, the first support piece 10 and the second support piece 11 are provided with the substrate 17 via the annular portions 33A, 33B formed by crushing the tips of the joint portions 32A, 32B protruding from the fixing holes 21A, 21B. It is fixed by joining.

As described above, in the height adjusting device for the head element of the embodiment, the groove portion 15A recessed in the head drum 15 is used.
In the case where the first head element 6 and the second head element 7 are displaced from each other by using the same base as a position reference due to the base being crossed over Also, it is possible to reduce the occurrence of displacement in the relative position between the first head element 8 and the second head element 9.

The height adjusting device for a head element according to the present invention is not limited to being used in a drum type magnetic head device, but may be adopted in other types of magnetic head devices.

[0049]

As described above, the head element height adjusting apparatus according to the present invention and the magnetic tape recording and / or the head height adjusting apparatus according to the present invention.
Alternatively, according to the reproducing apparatus, the heights of the first head element and the second head element facing the same base are adjusted by adjusting the first adjusting screw and the second adjusting screw. It is possible to reduce the occurrence of changes in the relative positions of the first head element and the second head element, and it is possible to reliably and stably record and reproduce the information signal.

[0050]

[Brief description of drawings]

FIG. 1 is a perspective view showing a height adjusting device of a head element according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a height adjusting device of the head element.

FIG. 3 is a partially cutaway front view showing a state in which the height adjusting device for the head element is attached to a head drum.

FIG. 4 is a vertical cross-sectional view showing another example of the head element height adjusting apparatus according to the present invention.

5 is a vertical cross-sectional view of a main part of the height adjusting device of the head element shown in FIG.

FIG. 6 is a perspective view showing still another example of the head element height adjusting apparatus according to the present invention.

FIG. 7 is a longitudinal sectional view of an essential part showing the height adjusting device of the head element shown in FIG.

FIG. 8 is a perspective view showing a conventional height adjusting device for a head element.

FIG. 9 is a partially cutaway front view showing a state in which a conventional height adjusting device for a head element is attached to a head drum.

FIG. 10 is a perspective view showing a state in which a conventional head element height adjusting device is attached to a head drum.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Head element height adjusting device, 6 1st head element, 7 2nd head element, 8 1st adjusting screw, 9 2nd adjusting screw, 10 1st supporting piece, 11 2nd supporting piece , 12, 13 Fixing screw, 14 Base, 15 Head drum, 15
A groove part, 23A adjustment screw mounting hole, 23B
Adjustment screw mounting hole, G1, G2 Magnetic gap

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G11B 5/52-5/53

Claims (10)

(57) [Claims] 1. An elastically deformable plate-shaped base whose both ends are fixed to the head drum so as to extend over an outer peripheral portion of a head drum formed in a bottomed cylindrical shape and to be bridged over a recessed groove portion. platform and are formed by elastically deformable plate material, each of the free end so as to opposed to each other at a position corresponding to the groove is recessed in the head drum, respectively piece fixed end is in the same base a first support piece and second support piece which is to have the support, respectively attached to the free end portion vicinity of the first support piece and the second support piece, the first support piece and the second of these a first adjusting screw and a second adjusting screw for the opposing distance between the support piece and the same base and adjustable, each free end of the said first support piece and the second support piece The first head element and the second head, which are joined and fixed,
And a head element, adjusting the first adjustment screw and the second adjusting screw
Thereby, the first head element and the second head
That the same base facing the height of the element is adjusted
A height adjusting device for a head element. Wherein said base is formed in a semicircular plate shape, height adjustment device of the head element according to claim 1, characterized in that provided along the inner periphery of the head drum. Wherein said base has two end portions are folded respectively so as to overlap with the base, said first support piece and the upper
Serial height adjustment device of the head element according to claim 1 or claim 2 and the second support piece is characterized by being formed integrally, respectively. Wherein said first support piece and the second support piece is drilled joined holes each to each of the fixed end portion, respectively integral to the two ends of the same base in these bonding holes The joint portions formed so as to project from the base are inserted, and the tip portions of the joint portions are crushed, so that the joint portions are jointed and fixed to both end portions of the same base, respectively. 2. The height adjusting device for a head element according to 2. 5. The base according to claim 1, wherein the base is made of an elastic plate material and is elastically deformed as the first adjusting screw and the second adjusting screw are adjusted.
The height adjusting device for a head element according to any one of 1. 6. An elastically deformable plate-shaped base whose both ends are fixed to the head drum so as to extend over an outer peripheral portion of a head drum formed in a bottomed cylindrical shape and to be bridged over a recessed groove portion. platform and are formed by elastically deformable plate material, each of the free end so as to opposed to each other at a position corresponding to the groove is recessed in the head drum, respectively piece fixed end is in the same base a first support piece and second support piece which is to have the support, respectively attached to the free end portion vicinity of the first support piece and the second support piece, the first support piece and the second of these a first adjusting screw and a second adjusting screw for the opposing distance between the support piece and the same base and adjustable, each free end of the said first support piece and the second support piece The first head element and the second head, which are joined and fixed,
A head element height adjusting device including a head element and a head element
In magnetic tape recording and / or reproducing apparatus, adjusting the first adjustment screw and the second adjusting screw
Thereby, the first head element and the second head
That the same base facing the height of the element is adjusted
And a magnetic tape recording and / or reproducing apparatus. 7. The base is formed in a semicircular plate, a magnetic tape recording and / or reproducing apparatus according to claim 6, characterized in that provided along the inner periphery of the head drum. 8. The base may, both end portions are folded respectively so as to overlap with the base, said first support piece and the upper
8. The magnetic tape recording and / or reproducing apparatus according to claim 6 or 7, wherein the second supporting piece is formed integrally with each other. 9. The first support piece and the second support piece is drilled joined holes each to each of the fixed end portion, respectively integral to the two ends of the same base in these bonding holes 7. The joint portions formed so as to protrude from the base are inserted, and the tip portions of these joint portions are crushed, so that the joint portions are jointed and fixed to both end portions of the same base, respectively. 7. The magnetic tape recording and / or reproducing apparatus according to 7. 10. The base is formed by an elastic plate material, the first adjusting screw and claims 6 to 9 with the second adjusting screw Chodo characterized in that it is elastically deformed The magnetic tape recording and / or reproducing apparatus according to any one of 1.