JPH01307010A - Rotary drum device - Google Patents

Abstract

PURPOSE:To improve the workability of an assembling, to eliminate the interference from a bobbin and to pull out a signal by using a flexible substrate for the signal pulling-out line of a head and the line to execute the power source supply of a coil bobbin, making the shape ring-shaped and executing the coaxial arrangement with the coil bobbin. CONSTITUTION:The title rotary drum device is the one to move a head in the width direction of a tape and to make a head locus at the time of recording and a head locus at the time of reproducing coincident even under an arbitrary tape sending speed. A ring-shaped flexible substrate (flexible) 52 to supply the power source to a coil bobbin 43 to drive a head 5 fitted to the tip of a plate spring 41 and the ring-shaped flexible 53 to pull out the signal from the head 5 to the external part are fitted at the concentric position to the coil bobbin 43 in a yoke 47 of a head driving part, and therefore, the contact, scrubbing, etc., with flexibles 52 and 53 and the coil bobbin, etc., do not occur at the time of driving the coil bobbin 43 in upper and lower directions.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is applicable to, for example, a video tape recorder (hereinafter referred to as VT).
(abbreviated as "R") was developed specifically to improve the playback quality of VTRs.The video head mounted on a rotating drum was made movable in the width direction of the magnetic tape to faithfully trace the magnetic recording traces. The present invention relates to a rotating drum device configured to rotate.

[Conventional technology]

FIG. 3 is a cross-sectional view showing the main parts of the rotating drum device disclosed in, for example, Japanese Patent Application No. 62-3713, FIG. 4 is a plan view thereof, FIG. 5 is a detailed plan view of the head drive section, and FIG. 6 is the third
7 is a front view of FIG. 5. FIG.

Now, in Figures 3 and 4, (4a) is the head (
5) is fixed at the tip and is a drive unit for moving the head (5) in the width direction of the tape. Reference numeral 50 indicates a recess provided in a part of the upper drum (3) to accommodate the drive part (4a), and is formed to have a large circumference in order to adjust the position of the drive part (4a). The head is positioned using the position adjustment hole (51), and the yoke (47) is fixed with the screw (48).
) to fix it. Note that (14) is a non-rotating contact for supplying control current to the drive unit (4a), and (15) is a rotating contact provided on a part of the pedestal (9) so as to be in sliding contact with the contact (14). The electrode (16) is a connection part that electrically connects the electrode (15) to the drive part (4a) via the connection part (12) and the wiring board (ll). The head (5) is connected to the connection part (1
0), a wiring board (11), and a connecting portion (12) to be electrically connected to the upper transformer (7).

Figures 5, 6, 7 and 8 show the drive section (4a)
are shown in detail, (41) is a non-magnetic plate spring with a head (5) attached to the tip, (43) is a coil bobbin attached to the plate spring (41), and (44) is a coil bobbin (
43) is a cylindrical coil for driving, and (42) is a leaf spring that supports the coil bobbin (43) and deforms together with the leaf spring (41) to enable linear movement of the coil bobbin (43). 45) is a cylindrical permanent magnet, (46) is a cylindrical permanent magnet arranged with the same magnetic poles as those of the cylindrical permanent magnet (45) facing each other, and (46a) is a pair of cylindrical permanent magnets (45), (46). ) is a ferromagnetic center ball, (47) is a yoke. This yoke (4
7) is a plate spring (41), (42), a cylindrical coil (44)
), a coil bobbin (43), a pair of cylindrical permanent magnets (4
5), (46) and a center ball (46a), and is divided into parts (47a), (47b), and (47c) for easy storage and assembly; This is a screw hole for attaching and fixing the yoke (47) to the upper drum. (49) is the yoke (
47). A head (5) projects through this window (49) and is arranged on the upper drum in sliding contact with the tape (13). Note that the cylindrical coil (
44) and the coil bobbin (43) are connected to a pair of cylindrical permanent magnets (45), (46) and a center ball (46).
a) and the annular gap formed between the yoke and the yoke so as to be movable up and down. Further, the leaf spring (41) is held between parts (47a) and (47b) of the yoke (47), and the leaf spring (42) is held between parts (47b) and (47c). .

Referring to FIG. 6, the magnet (45) generates a magnetic flux (D
) are generated radially from the center ball (46a) toward the yoke. Similarly, the magnet (46) is connected to the part (47b
) and (47c) create a closed magnetic path in the opposite direction to generate magnetic flux (E), and both magnetic fluxes (D) and (E) cross the annular gap in the same direction. Thus, the cylindrical coil (4
4) is crossed by the total magnetic flux of magnets (45) and (46). From the contact (14) to the electrode (15) to the coil (44)
, through the connecting parts (12) and (18), the coil (44), coil bobbin (43), and head (5) move vertically in a parallel straight line as one. The head (5) is thus displaced in the tape width direction.

[Problems to be Solved by the Invention] Conventional rotating drum devices were configured as described above, and because the signal line from the head was drawn out by a lead wire, interference with the bobbin was likely to occur internally, and the head This has a large effect on drive loss, and also has poor assembly workability, leading to problems such as an increase in the defective rate.

This invention was made to solve the above-mentioned problems, and aims to improve the workability of assembly and to be able to extract signals without interfering with the drive of the head drive section.

[Means to solve the problem]

The rotating drum device according to the present invention uses a flexible substrate (hereinafter referred to as a flexible board) with good assembly workability for the lead signal line for the head and the power supply line for the head drive coil bobbin, and The shape of the flexible cable is circular or semicircular.

[Effect]

In this invention, a flexible cable with good workability is used for the signal lead-out line of the head and the line for supplying power to the coil bobbin for driving the head, and by making the flexible cable into an annular shape and extending approximately coaxially with the coil bobbin, the coil bobbin This has the effect of preventing interference with the above-mentioned lead wire.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, (52) and (53) are annular flexible plates attached to the yoke (47) of the head drive section (4a), the shape of which is shown in FIG. The annular flexible cable (52) is for supplying power to the coil bobbin (43), and the annular flexible cable (53) is for extracting signals from the head to the outside and has a conductor (60). The shape is as shown in Figure 2. Flexible (52), (
53) is annular and is mounted coaxially with the coil bobbin (43), so that when the coil bobbin is driven up and down, there will be no contact or rubbing between the flexible cable and the coil bobbin.

The manner in which the annular flexible cable is attached will be explained in detail. Figure 2(b)
and (c), (A) and (B) are leaf springs (41
), (42) are attached so as to sandwich them, (A) is the movable side, and (B) is the fixed side. In other words(
A) is connected to the coil bobbin (43), (B) is connected and held to the yoke (47) (see Figure 1), and the annular flexible part (A') is attached to the movable side (A). and the part (B') of the annular flexible cable is connected to the fixed side (B').
).

In addition, in the above example, the shape of the flexible cable was annular, but
It may also have a semicircular arc shape.

Further, in the above embodiment, the case where the device is used as a yoke for driving a video head of a VTR has been described, but the same effect can be obtained even if the device is used to extract power from a speaker or the like that moves up and down.

[Effect of the invention 1 As described above, according to the present invention, the power source for driving the coil bobbin (43) and the signal for the video head are drawn out using the annular flexible cable, which improves workability during assembly. This has the effect of providing a highly reliable head drive unit without interfering with the drive unit.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional side view showing a head driving device according to an embodiment of the present invention, Fig. 2 is an external view of the annular flexible plate and leaf spring used in the present invention, and Fig. 3 is the main part of a conventional rotating drum device. 4 is a plan view thereof, FIG. 5 is a detailed plan view of the head drive section, FIG. 6 is a sectional view of FIG. 5,
FIG. 7 is a front view of FIG. 5, and FIG. 8 is a detailed view of the leaf spring. In the figure, (41) and (42) are leaf springs, (43) a coil bobbin, (45) and (46) are cylindrical permanent magnets, (
47) is a yoke, (49) is a window, and (52) and (53) are annular flexible plates. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Patent Attorney Masuo Oiwa Figure 1 Figure 2 Figure 5 Figure 6 Figure 8

Claims (1)

[Claims] (1) A rotating drum device that moves the head in the width direction of the tape so that the head trajectory during recording and the head trajectory during playback match even at any tape feed speed. a magnetic yoke arranged with a gap therearound to form a magnetic path for the lines of magnetic force from the permanent magnet; and a yoke arranged within the gap to cross the lines of magnetic force and supported movably in a direction orthogonal to the lines of magnetic force. The coil has a structure in which the head moves in accordance with the movement of the coil by energizing the coil, and the coil has one or more discontinuous grooves that are substantially concentric. Two or more non-magnetic materials or materials with properties similar to those of non-magnetic material, which are provided so that part or almost the entire outer periphery is held by a fixed member, and a coil or coil bobbin is held on the innermost periphery. In a structure supported by a circular or nearly circular spring formed by A rotating drum device characterized in that the flexible substrate and the coil bobbin are arranged substantially coaxially, thereby eliminating interference with the flexible substrate when the coil bobbin is driven up and down.