JPS6241375Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is ideal for application to magnetic recording and reproducing devices that record video signals, digital signals, etc. on magnetic tape at high density, such as VTRs and DMS (Digital Mass Storage) for computer peripherals. In particular, the present invention relates to a horizontal scanning rotary head drum capable of recording a large number of recording tracks parallel to the tape running direction on a magnetic tape or the like in the width direction of the tape.

A conventional example of this type of rotary head drum for horizontal scanning is shown in FIGS. 5 and 6 of Japanese Unexamined Patent Publication No. 52-32306.

In this conventional example, the rotating drum is rotated horizontally in a fixed position, while the magnetic head is intermittently moved in the vertical direction, which is the width direction of the magnetic tape, inside a large vertically long window hole provided in the rotating drum. This is what I did.

However, in a structure in which the magnetic head is moved vertically within a large vertically long window, problems such as air flow occur in the large window.
The contact of the rotating head with the magnetic tape becomes very poor, making it impossible to perform highly accurate recording and reproduction.

Furthermore, the intermittent drive mechanism in this conventional example for intermittently moving the magnetic head vertically within the rotating drum is intermittently rotated by a Geneva gear driven by a drive shaft and its driven gear. The magnetic head is assembled from a number of parts and has a helical cam that moves the magnetic head intermittently in the vertical direction along a vertical guide axis.

Therefore, the intermittent drive mechanism has a large number of parts and a large number of assembly steps, and is complex in structure and expensive. Moreover, the intermittent drive mechanism, which has a complex structure and is very heavy, must be built into the rotating drum and rotated together with the rotating drum, which makes the rotating drum very heavy and the rotational speed of the rotating drum, that is, the rotating head. Control becomes extremely difficult, leading to deterioration of recording and reproduction characteristics. Furthermore, in a structure in which the magnetic head is intermittently moved vertically by a helical cam along a vertical guide axis, the magnetic head tends to rattle and vibrate, making it extremely difficult to control the tracking of the magnetic tape by the magnetic head. This is difficult and also leads to deterioration of recording and reproduction characteristics.

The present invention was devised to correct the above-mentioned defects, and includes: a vertical sleeve attached to the substrate so as to be movable up and down; a vertical rotation drive shaft rotatably attached to the substrate; a vertical rotating drum that is rotatably supported by the sleeve and configured to be movable relative to the axis of the rotational drive shaft while receiving rotational force from the rotational drive shaft; a rotating head that is fixedly fixed and protrudes from a small window hole on the outer circumferential surface of the rotating drum; a recording and reproducing tape that is loaded horizontally on the outer circumferential surface of the rotating drum; and a nut installed in the sleeve; By sequentially driving the feed screw rotatably attached to the board and screwed into the nut, and the rotary drive shaft, the length of the horizontal tape is integrated with the rotary drum and the rotary head. The first to rotate in the direction
By intermittent rotational driving of the feed screw by the motor and the nut, the rotating drum is integrally moved with the rotating head through the sleeve through the intermittent screw feeding action of the feed screw and the nut. This rotary head drum for horizontal scanning is equipped with a second motor that moves the tape intermittently at a constant pitch in the vertical width direction of the tape.

According to the present invention constructed in this way, the rotary drum to which the rotary head is fixed is supported by a vertically movable sleeve, and the feed screw and nut are intermittently rotated by the second motor. The rotary drum is moved intermittently in the tape width direction together with the rotary head through the sleeve by the intermittent screw feeding action of the rotary drum, while the rotary drum is continuously rotated by the second motor. The rotary drive shaft rotates the rotary head in addition to the intermittent movement of the rotary head, and is completely different from an intermittent drive mechanism that moves the rotary head intermittently in the tape width direction. The intermittent drive mechanism is completely separated from the rotation drive mechanism of the rotation drum and provided outside the rotation drum so that the rotation drum can be rotated continuously regardless of the rotation of the rotation drum.

An embodiment in which the present invention is applied to a horizontal scanning rotary head drum for a VTR, DMS, etc. will be described below with reference to the drawings.

1 and 2 show the first embodiment, in which 1 is an upper horizontal substrate, 2 is a lower horizontal substrate, and 3 is a vertical substrate, which are connected together in a substantially U-shape. has been done. Next, reference numeral 4 denotes a cylindrical bearing, which is held by a holder 5 and fixed vertically to the vertical substrate 3. Note that 6 is a retaining screw for preventing rotation of the bearing 4. A cylindrical sleeve 7 is inserted coaxially into the bearing 4 and supported so as to be movable in the vertical direction. Note that grooves 8 and 9 are provided on the outer circumferential surface of the sleeve 7 and on the inner circumferential surface of the bearing 4, and these grooves 8 and 9 are parallel to the axial direction.
A plurality of steel balls 10 are inserted in a vertical line between the sleeves 9 and 9, and these steel balls 10 stop the rotation of the sleeve 7, so that the sleeve 7 can slide smoothly only in the vertical direction. ing.

Next, 12 is a cylindrical rotating drum, and a rotating head 13 consisting of, for example, a pair of magnetic heads is attached to this rotating drum 12. Note that both rotating heads 13 are connected to the horizontal wall 1 in the rotating drum 12.
It is screwed and fixed to 2a with a set screw 14,
These head tips 13a are provided on the cylindrical wall 12b of the rotating drum 12.
It is inserted through a small window hole 15 into which only part a can be inserted, and is slightly protruded from the outer circumferential surface 12c. Further, a cylindrical drum center shaft 16 is vertically fixed to the center of the rotating drum 12, and the drum center shaft 16 is inserted into the sleeve 7 from below. The drum center shaft 16 is rotatably supported by the sleeve 7 via a pair of upper and lower ball bearings 17, and the rotary drum 12 is rotatable about its axis along with the sleeve 7 in the vertical direction ( It is configured to be movable in the axial direction).

Next, reference numeral 19 denotes a rotary drive shaft constituted by a spline shaft, which is disposed coaxially and perpendicularly below the rotary drum 12. Note that this rotary drive shaft 19 has a pair of upper and lower ball bearings 21 mounted on a bearing block 20 fixed to the lower horizontal substrate 3.
It is rotatably supported via. A motor 22, which is a first motor, is attached to the lower part of the bearing block 20, and the motor shaft of the motor 22 is configured at the lower end side of the rotary drive shaft 19. It is configured to be directly coupled and driven. On the other hand, the upper end side of the rotary drive shaft 19 is inserted from below into a spline bearing 23 fixed to the lower end of the drum center shaft 16, and the rotary drive shaft 19 is in a state in which rotational force is constantly transmitted to the rotary drum 12. Rotating drum 12
are engaged so that they are relatively movable in the axial direction (vertical direction). A relay board 24 is fixed to the outer periphery of the lower surface of the spline bearing 23, and a relay board 27 is fixed to the upper surface of the disk 26 fixed to the longitudinally intermediate portion of the rotary drive shaft 19. Also, on the outer periphery of the rotational drive shaft 19, a disc 26 and a bearing block 20 are connected.
A rotary transformer 31 consisting of a rotating ring 29 and a fixed ring 30 is provided between the two.
Both rotary heads 13 are electrically connected to a relay board 24 via lead wires 25, respectively.
Further, both the relay boards 24 and 27 are electrically connected by a lead wire 28 having a sufficient length, and electrically connected to the rotating ring 29 of the rotary transformer 31.
The fixing ring 30 is electrically connected to a predetermined circuit. Further, a pulse generator 34 consisting of a magnet 32 and a coil 33 is provided between the disc 26 and the bearing block 20.

Next, 36 is a feed screw, which is disposed vertically on the upper part of the sleeve 7 with the same axis.
The feed screw 36 is rotatably supported by a heat receiving block 37 fixed to the upper horizontal substrate 1 via a pair of upper and lower ball bearings 38. The feed screw 36 is inserted into the sleeve 7 from above and screwed into a nut 39 fixed to the upper end of the sleeve 7. Note that the inner peripheral thread of the nut 39 is constituted by a ball screw 40. The feed screw 36 is inserted through a nut 39 and into the drum center shaft 16, and the lower end of the feed screw 36 is supported within the drum center shaft 16 via a ball bearing 42. On the other hand, a second motor 43 is attached to the lower part of the upper horizontal board 1, and a timing pulley 45 is fixed to the upper end of the motor shaft 44.
and a timing pulley 46 fixed to the upper end of the feed screw 36 are interlocked by a timing belt 47. The motor 43 is constituted by a pulse motor, and is configured to be driven to rotate intermittently at fixed time intervals using a pulse signal. The motor 43 is also provided with a tachogenerator 52 which is a combination of a slit disk 50 and a photocoupler 51, for example.

A magnetic tape 54, which is a tape for recording and reproducing, is horizontally loaded (wound) on the outer circumferential surface 12c of the rotating drum 12, and is stabilized by a tape guide (not shown) as shown in FIG. It is configured to run horizontally at a predetermined height shown in .

According to the horizontal scanning rotary head drum configured as described above, first, the rotary drive shaft 19 is rotationally driven by the motor 22, and the rotary drum 12 is rotated in a predetermined direction via the spline bearing 23 and the drum center shaft 16. Driven in continuous rotation at high speed.

Meanwhile, at the same time, the motor shaft 44 is intermittently rotated by the motor 43 at regular time intervals.
timing pulley 45, timing belt 47,
The feed screw 36 is rotated intermittently at regular time intervals in a non-slip state via the timing pulley 46. As a result, the feed screw 36 and nut 39
The rotating drum 12 is moved intermittently at a constant pitch within a vertical movement range H that is slightly smaller than the width of the magnetic tape 54 shown in FIG. Moved vertically.

As a result of the above, both rotating heads 13 are connected to the magnetic tape 54.
While being rotated in a horizontal plane parallel to the direction of travel,
It is intermittently moved at a constant pitch in the vertical direction, which is the width direction of the magnetic tape 54.

However, the intermittent vertical movement of the two rotating heads 13 of the lever while horizontally rotating the magnetic tape 5
This is done while the magnetic tape 54 is running at a low speed in the horizontal direction, or while the horizontal running of the magnetic tape 54 is intermittently stopped, and while the two rotary heads 13 are intermittently moving vertically within the vertical movement range H. , magnetic tape 5
4, a large number of recording tracks completely horizontal to the tape running direction are recorded in the width direction of the tape.

The rotation and vertical movement of the rotary drum 12 during the above operation are controlled by two independent motors 22 and 4.
3, it is possible to move the rotating drum 12 freely in the width direction of the tape independently of its rotation, and it is easy to play back stills, slow motions, etc. on a VTR or the like. I can do it. In addition, the rotary transformer 31 and the pulse generator 34 are connected to the rotary drive shaft 1 that does not move vertically at all.
9 side, it is possible to send and receive recording or reproduction signals and control the rotational speed of the motor 22 without being affected by the vertical movement of the rotary drum 12.

Next, FIG. 3 shows a second embodiment, in which the rotary drive shaft 19 is constructed as a hollow shaft, and the center hole 56 is provided with both the relay boards 24,
The lead wire 28 connecting between the two ends of the lead wire 27 is inserted through the lead wire 28. With this configuration, twisting of the lead wire 28 during rotation of the rotary drum 12 as in the first embodiment can be prevented, and the risk of wire breakage can be eliminated.

Although the embodiments of the present invention have been described above, further modifications can be made based on the technical idea of the present invention.

For example, it is possible to directly drive the feed screw 36 with the motor 43.

Further, the rotational drive shaft 19 may be a serration shaft or a shaft provided with a key or a keyway.

It is also possible to vertically move the sleeve 7 by fitting the key into the keyway.

As described above, in the present invention, a rotary head is fixed to a rotary drum, and the rotary drum is moved intermittently in the tape width direction together with the rotary head. The window hole for protrusion can be made extremely small. Therefore, problems such as air flow caused by the large size of the window holes do not occur, and the rotary head comes into very good contact with the tape, allowing highly accurate recording and reproduction.

In addition, the intermittent drive mechanism is completely separated from the rotation drive mechanism of the rotary drum so that the rotating drum can be rotated continuously, completely independent of the intermittent drive mechanism that intermittently moves the rotary head in the tape width direction. Since it is provided outside the drum, the weight of the rotating drum can be made very light regardless of the intermittent drive mechanism. Therefore, it is very easy to control the rotational speed of the rotating drum, that is, the rotating head, and highly accurate recording and reproduction can be performed.

In addition, since the rotary head is moved intermittently in the tape width direction by the screw feeding action together with the rotary head, there is no rattling or vibration in the rotary head, and the tracking of the tape by the rotary head can be controlled. This allows for easy and accurate recording and playback without track deviation.

Furthermore, the intermittent drive mechanism that intermittently moves the rotary head in the tape width direction by the intermittent screw feeding action caused by the intermittent rotation of the feed screw is similar to the Geneva gear, helical cam, and guide shaft shown in the conventional example. Compared to intermittent drive mechanisms that are assembled from a large number of parts, the number of parts and assembly man-hours are very simple, and the cost is low.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and
FIG. 1 is a perspective view of the first embodiment, FIG. 2 is a vertical cross-sectional view of the same, and FIG. 3 is a cross-sectional view of the main part of the second embodiment. In addition, in the symbols used in the drawings, 1... Upper horizontal board, 2... Lower horizontal board, 3... Vertical board, 4... Bearing, 7... Sleeve, 12... Rotating drum, 13... Rotating head. , 16...Drum center shaft, 19...Rotation drive shaft, 22...Motor (first motor), 23...Spline bearing, 36...
...Feed screw, 39...Nut, 43...Motor (second sweater), 47...Timing belt, 5
4...Magnetic tape (recording/playback tape).

Claims (1)

[Scope of utility model registration request] A vertical sleeve is attached to the substrate so as to be movable up and down, a vertical rotational drive shaft is rotatably attached to the substrate, and the sleeve is rotatably supported, and rotational force is transmitted from the rotational drive shaft. a vertical rotating drum configured to be relatively movable in the axial direction of its rotational drive shaft; and a rotating head fixed to the rotating drum and protruding from a small window hole on the outer peripheral surface of the rotating drum. , a recording/playback tape loaded horizontally on the outer periphery of the rotating drum, a nut attached to the sleeve, and a feed screw rotatably attached to the substrate and screwed into the nut. , a first motor that rotates the rotary drum together with the rotary head in the longitudinal direction of the horizontal tape by continuously rotationally driving the rotary drive shaft; and a first motor that rotates the feed screw intermittently. By doing so, the rotating drum is integrally moved with the rotating head through the sleeve by the intermittent screw feeding action of the feed screw and the nut intermittently at a constant pitch in the vertical width direction of the horizontal tape. and a second motor for moving the horizontal scanning head drum.