JPH0633540Y2 - Tape recorder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The tape recorder of the present invention will be described according to the following items.

A. Industrial fields of use B. Overview of the device C. Prior art [Fig. 6] D. Problems to be solved by the device [Fig. 6] E. Means for solving the problem F. Example [Figs. 1 to 5] a. Recording / reproducing unit [Figs. 1 to 4] a-1. Mechanical chassis a-2. Bearing a-3. Capstan shaft etc. b. Printed circuit board [Fig. 1] To FIG. 4] c. Motor [FIGS. 1 to 4] c-1. Structure c-2. Mounting to printed circuit board d. Earth spring [FIGS. 1 to 4] e. Modification [Fifth] Fig.] G. Effect of device (A. Industrial application field) The present invention relates to a novel tape recorder. Specifically, the present invention relates to a tape recorder having a mechanical chassis made of synthetic resin and a capstan shaft rotatably supported on the mechanical chassis via a bearing made of a conductive material.
The electrostatic grounding of the capstan shaft can be performed by using the members required for the tape recorder. Moreover, the soldering part is eliminated in the system path for grounding and the soldering work is unnecessary. The present invention aims to provide a new tape recorder that can be used.

(B. Outline of the Invention) The tape recorder of the present invention is fixed to a mechanical chassis made of synthetic resin, a capstan shaft rotatably supported by the mechanical chassis through a bearing made of a conductive material, and the mechanical chassis or a printed circuit board. And a motor having a casing or mounting plate made of a conductive material connected to the ground pattern of the printed circuit board, the casing or mounting plate of the motor and the bearing being provided with a spring made of a conductive material. The capstan shaft and the ground pattern of the printed circuit board are electrically connected by making contact with each other, thereby making it possible to eliminate the need for soldering work for the means for grounding the static electricity of the capstan shaft. The workability is excellent and the reliability is high.

(C. Prior art) [Fig. 6] Generally, a tape recorder is provided with a capstan shaft that allows a magnetic tape to be sandwiched between a pinch roller and rotated to drive the magnetic tape. In addition, such a capstan shaft is usually provided with some grounding means in order to prevent the electrostatic charge carried by the capstan shaft from destroying the recording signal of the magnetic tape. Is performed by forming a bearing portion that supports the capstan shaft from a conductive material and electrically connecting the bearing portion to some grounding portion, for example, a mechanical chassis made of metal.

By the way, recently, in a relatively small tape recorder, a mechanical chassis made of synthetic resin may be used in order to reduce the weight, and the mechanical chassis is made of synthetic resin. Since the mechanical chassis cannot be used for the grounding part for grounding the capstan shaft, it is necessary to use a grounding body other than the mechanical chassis as the grounding part.

Therefore, in a conventional tape recorder whose mechanical chassis is made of synthetic resin, for example, as shown in FIG. 6, a capstan shaft c is rotatably mounted on a metal bearing b supported by a mechanical chassis a. In addition to supporting, the bearing b and the ground pattern formed on the printed circuit board d are connected by a lead wire e.

(D. Problems to be solved by the device) [Fig. 6] However, such a grounding means needs to solder the lead wire e to the grounding pattern of the bearing b and the printed circuit board d. Not only is it time-consuming, but also requires a certain amount of skill, and the soldering part of the lead wire e may come off when the tape recorder is inspected or repaired. There is a problem of being low.

Further, soldering in such a place is considerably difficult to perform by an automatic machine, and in the end, it has to be done manually, which is one of the causes for increasing the cost of the tape recorder. It was

(E. Means for Solving Problems) By the way, the tape recorder requires a motor for driving the capstan shaft and other driven members, and such a motor is usually a metal casing. Alternatively, it is often attached directly or indirectly to a mechanical chassis or a printed circuit board by a metal mounting plate.

In view of the above, the tape recorder of the present invention solves the above problems by electrically connecting a part of a casing or a mounting plate made of a conductive material of a motor to a ground pattern of a printed circuit board. A part of the spring made of a conductive material is brought into contact with the bearing of the capstan shaft and the other part is brought into contact with the casing of the motor or the motor mounting plate.

Therefore, according to the tape recorder of the present invention, the capstan shaft and the ground pattern of the printed circuit board are electrically connected to each other through the capstan bearing, the spring and the casing or mounting plate of the motor, and the capstan shaft is charged with static electricity. Is grounded to the ground pattern of the printed circuit board through the bearing, spring and motor casing or mounting plate, and the capstan bearing is connected to the motor casing or mounting plate by contacting a part of the spring. It is not necessary to carry out the soldering work because it is done only by itself, and the contact state of the spring with the bearing of the motor and the casing or the mounting plate can be stably maintained by the elastic force of the spring.

(F. Embodiment) [FIGS. 1 to 5] The details of the tape recorder of the present invention will be described below with reference to the illustrated embodiment.

(A. Recording / reproducing unit) [FIGS. 1 to 4] 1 is a tape recorder, and 2 is a recording / reproducing unit for recording and / or reproducing on a magnetic tape.

(A-1. Mechanical chassis) 3 is a mechanical chassis which is a base of the recording / reproducing unit 2, and is formed entirely of synthetic resin in a plate shape, and its front end (the downward direction in FIG. 2 is the front side). , The upward direction is the rear side, the leftward direction in the figure is the left side, and the rightward direction is the right side in the following description. .) A boss portion 4 that protrudes vertically is formed at the right end of the boss.

(A-2. Bearing) 5 is a bearing for supporting a capstan shaft, which will be described later. The bearing 5 is formed of a conductive material into a substantially cylindrical shape, and the upper and lower ends thereof project from the boss portion 4 and the boss portion. 4 and is fixed to the mechanical chassis 3 by insert molding, for example.

The portion 6 of the bearing 5 projecting upward from the boss portion 4 has a larger diameter than the other portions, and
The upper end 6a is frustoconical and the lower end 6b is the middle part.
The diameter is smaller than that of 6c. Therefore, a step surface 6d is formed between the lower end portion 6b and the intermediate portion 6c and extends downward in an annular shape.

(A-3. Capstan shaft, etc.) 7 is a capstan shaft, and a flywheel 8 is fixed to the lower end portion thereof, and a belt pulley 9 is fixed to the flywheel 8.

The lower half of the capstan shaft 7 is rotatably inserted into the bearing 5 and is prevented from coming off.

10 and 10 are cassette positioning pins standing upright from the mechanical chassis 3, 11 and 11 are reel stands rotatably supported by the mechanical chassis 3, and 12 is movably supported by the mechanical chassis 3 in the front-rear direction (not shown). A magnetic head fixed to a head base, 13 is a pinch roller arm, 14 is a rotatably supported by the pinch roller arm 13, and a pinch roller that opposes a portion of the capstan shaft 7 protruding upward from the bearing 5 from the front. Is.

(B. Printed circuit board) [Figs. 1 to 4] 15 is a printed circuit board, on the upper surface of which conductors 16, 16, ...
(Only one conductor 16 is shown.) Is adhered, a predetermined wiring pattern is formed, electronic parts (not shown) are mounted, and a part of the printed circuit board 15 is attached to the mechanical chassis 3.
Is arranged so as to overlap with the right end of the above from above. still,
The illustrated conductor 16 is a ground conductor.

17a, 17b and 17c are mounting holes formed in a portion of the printed circuit board 15 near the front end, and these mounting holes 17a, 17b and 17c are provided.
c is for attaching a motor to be described later to the printed circuit board 15 and has a long and narrow rectangular shape, and is provided so as to be arranged at substantially equal intervals in the circumferential direction. The ground conductor 16 is open in the ground conductor 16 and extends to the inner surface thereof.

Reference numeral 18 denotes an insertion hole formed in the printed circuit board 15 at a position relatively close to the bearing 5 for inserting a spring hook piece described later.

(C. Motor) [FIGS. 1 to 4] 19 is a motor for driving the capstan shaft 7.

(C-1. Structure) The motor 19 is composed of a casing 20 in which a rotor and a stator (not shown) are incorporated, a mounting plate 21 fixed to the upper surface of the casing 20, and a rotary shaft 22 fixed to the rotor.
A belt pulley 23 having a small diameter is fixed to a portion of the rotary shaft 22 of the rotary shaft 22 protruding from the casing 20.

The mounting plate 21 is made of a conductive material and is formed of a metal into a substantially disc shape, and the mounting pieces 24a, 24b, and 24c are located above the outer peripheral edge of the mounting plate 21 at positions substantially equidistant from each other in the circumferential direction. The mounting pieces 24a, 24b, and 24c are formed so as to have a substantially rectangular shape that is long in the vertical direction.

Reference numeral 25 is a spring hook piece projecting upward from the outer peripheral edge of the mounting plate 21, and the outer shape is a rectangle long in the vertical direction, and the upper approximately half 26 thereof has a central portion in the width direction. Notch 2 which is almost L-shaped and is opposite to each other
By forming 7 and 27, when viewed from the plate thickness direction, the left and right ends have a T-shape with downwardly projecting portions.

The spring hook 25 is positioned such that its upper portion 26 faces the bearing 5 in the plate thickness direction when the motor 19 is attached to the printed circuit board 15.

(C-2. Mounting on printed circuit board) Then, the motor 19 is mounted on the printed circuit board 15 by the motor.
19 from below the printed circuit board 15 to the mounting plate 21
24a, 24b and 24c in the mounting holes 17a, 17b and 17c,
Insert the spring hook pieces 25 into the insertion holes 18, and
By twisting the portions of 4b and 24c protruding upward from the mounting holes 17a, 17b, and 17c by approximately 90 °, that is, by twisting so as to face in a direction substantially orthogonal to the plate thickness direction of the lower end portion. To be done.

Then, when the motor 19 is attached to the printed circuit board 15 in this manner, the mounting pieces 24a, 24b and 24c are attached to the printed circuit board 1.
The inner surface of the mounting holes 17a, 17b, and 17c formed in FIG. 5 comes into contact with the inner surface of the mounting hole 17a, and the ground conductor 16 is partially formed on the inner surface of the mounting hole 17a. The attached mounting piece 24a comes into contact with the ground conductor 16, whereby the mounting plate 21 is electrically connected to the ground conductor 16.

Further, in this state, most of the spring hook piece 25 of the mounting plate 21 except the lower end portion thereof protrudes upward from the insertion hole 18 of the printed circuit board 15 and is relatively in contact with the bearing 5 provided in the mechanical chassis 3. They will face each other after a short distance.

28 is a belt pulley 23 of the motor 19 and the capstan shaft 7
It is a transmission belt stretched between the belt pulley 9 fixed to the.

(D. Earth Spring) [FIGS. 1 to 4] 29 is an earth spring made of a conductive material. The earth spring
29 is a so-called torsion spring, and its coil portion 29a
Is externally fitted to the lower end 6b of the portion 6 of the bearing 5 protruding upward from the boss 4, and then the two arms 29b, 29b are brought closer to each other against the resilience and the tip of the motor 19
Engage with the upper ends of the notches 27, 27 of the spring hook pieces 25 provided on the mounting plate 21.

Therefore, the coil portion 29a of the earth spring 29 has two arms 29b and 29b.
Since b is reduced in diameter by being brought close to each other, a part thereof comes into contact with the lower end portion 6b or the stepped portion 6d of the bearing 5, and at the contacted portion, the stepped surface 6d prevents upward pull-out, and The tips of the two arms 29b, 29b elastically contact the inner edges 27a, 27a of the cutout portions 27, 27 of the spring hooking piece 25, which are farther from each other, and move upward by the upper edges 27b, 27b of the cutout portions 27, 27. It is prevented that the engagement with the spring hook piece 25 is disengaged.

As a result, the capstan shaft 7 is electrically connected to the ground conductor 16 of the printed circuit board 15 through the bearing 5, the ground spring 29, and the mounting plate 21 of the motor 19, so that the static electricity of the capstan shaft 7 is charged. Is a bearing 5-ground spring 29-mounting plate 21 and ground conductor 16 of printed circuit board 15
Will fall into.

(E. Modification) [FIG. 5] FIG. 5 shows a modification of the grounding means of the capstan shaft 7.

First, in the above-described embodiment, the arm 29 of the earth spring 29 is
The tips of b and 29b are elastically contacted with the inner edges 27a and 27a of the two notches 27 and 27 of the spring hook 25 formed on the mounting plate 21 of the motor 19, respectively. 5th spring hook piece
As shown in the figure, the spring hook 30 is simply T-shaped, and the arms 29b, 29b of the earth spring 29 are made to intersect each other in the middle, and the vertical parts 30a of the spring hook 30 are contacted so as to be sandwiched from both sides. May be.

In addition, the mounting pieces 24a, 24b, 24 provided on the mounting plate 21 of the motor 19
When c can be formed directly on the upper wall of the casing 20, the casing 20 may be directly attached to the printed circuit board 15 without the attachment plate 21, and the casing 20 may be any earth member. If grounded,
Just keep the earth spring 29 in contact with the casing 20,
That is, the capstan shaft 7 can be grounded without connecting the motor to the ground conductor of the printed circuit board.

The motor 19 does not necessarily have to be attached to the printed circuit board 15, and may be attached to the mechanical chassis 3. Further, the motor is not limited to the one for driving the capstan shaft. A motor for driving a reel base or other driven member may be used as long as it is arranged at a position relatively close to the capstan shaft 7.

Further, in the above embodiment, the arms 29b, 2 of the earth spring 29 are
A spring hook for contacting 9b is provided separately from the mounting pieces 24, 24, ..., However, this mounting piece may also serve as the spring hook.

In addition, although the torsion spring is used as the earth spring in the above-described embodiment, the present invention is not limited to this, and for example, a normal leaf spring may be used to elastically contact both ends of the capstan bearing and the motor separately.

When a torsion spring is used, some protrusion may be formed on the mechanical chassis, and the coil portion of the torsion spring may be supported by this protrusion so that the two arms contact the bearing and the motor separately.

(G. Effect of Invention) As is clear from the above description, the tape recorder of the present invention is a capstan shaft rotatably supported by a mechanical chassis made of synthetic resin through a capstan bearing made of a conductive material. And a casing fixed to the mechanical chassis or the printed circuit board and having a casing made of a conductive material or a motor mounting plate connected to a ground pattern of the printed circuit board, the tape recorder comprising a spring made of a conductive material. The part is brought into contact with the bearing of the capstan shaft and the other part is brought into contact with the casing of the motor or the motor mounting plate.

Therefore, according to the present invention, the capstan shaft is electrically connected to the ground pattern of the printed circuit board through the capstan bearing, the spring, and the motor casing or mounting plate, so that the static electricity on the capstan shaft is bearing,
It will fall on the ground pattern of the printed circuit board through the spring and the casing or mounting plate of the motor.

The electric connection between the capstan bearing of the spring and the casing or the mounting plate with the motor is completed by elastically contacting a part of the spring with the casing or the mounting plate of the motor and the capstan bearing. Since no soldering work is required for the capstan shaft, the work for providing the grounding means of the capstan shaft is extremely simple, and the contact state of the spring with the bearing and the casing of the motor or the mounting plate is the same. Since it is stably held by the elastic force of the capstan shaft, the reliability of the capstan shaft in the grounded state can be made extremely high.

Further, the spring that electrically connects the capstan bearing and the motor can be easily removed as necessary when inspecting or repairing the tape recorder, which facilitates the above-described inspection work and the like. It is also possible to incorporate the spring by an automatic machine by devising the contact structure of the spring with respect to the bearing and the motor.

In the above embodiment, the motor is mounted on the printed circuit board, and the mounting piece provided in a rising shape from the motor mounting plate is inserted into the mounting hole formed in the ground pattern area of the printed circuit board. In addition, the portion projecting from the mounting hole is twisted to engage with the opening edge of the mounting hole. By doing so, electrical connection between the motor and the ground pattern of the printed circuit board can be achieved. Since the motor can be attached to the printed circuit board by using the mounting means, the workability can be further improved.

Further, in the first embodiment, a spring hooking piece whose tip portion projects from the printed board when the motor is attached to the printed board is formed on the motor mounting plate, and the tip end portion of the spring hooking piece is placed on the capstan bearing side. Facing each other and having a substantially T-shape, and the left and right ends thereof are bent downward, the coil portion of the torsion spring is fitted onto the capstan bearing, and the tips of the two arms are attached to the spring hook piece. Since it is elastically locked to the tip end portion, the contact of the coil portion of the torsion spring or the bearing or the spring hook piece of the tip end portion does not easily come off.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 5 show an embodiment of a tape recorder according to the present invention. FIG. 1 is a perspective view of essential parts, FIG. 2 is a plan view, and FIG. An enlarged sectional view taken along the line III-III in FIG.
FIG. 4 is an exploded perspective view of the main part, FIG. 5 is a perspective view of the main part showing a modified example of the contact structure of the earth spring with respect to the motor, and FIG. 6 is an example of the conventional grounding means of the capstan. It is a side view. Explanation of code 1 …… tape recorder, 3 …… mechanical chassis, 5 …… bearing, 7 …… capstan shaft, 15 …… printed circuit board, 16 …… ground pattern, 19 …… motor, 20 …… casing, 21 ...... Motor mounting plate, 29 …… Spring, 29a …… (Spring) part, 29b …… (Spring) other part

Claims (2)

[Scope of utility model registration request] 1. A capstan shaft rotatably supported by a mechanical chassis made of synthetic resin via a capstan bearing made of a conductive material, and a casing fixed to the mechanical chassis or the printed circuit board and made of a conductive material. A tape recorder having a motor connected to a ground pattern of a printed circuit board, wherein a part of a spring made of a conductive material is brought into contact with a bearing of a capstan shaft and another part is brought into contact with a casing of the motor. A tape recorder characterized by 2. A capstan shaft rotatably supported on a mechanical chassis made of synthetic resin via a capstan bearing made of a conductive material, and a motor mounting made of a conductive material while being fixed to the mechanical chassis or the printed circuit board. A tape recorder having a motor connected to a ground pattern of a printed circuit board, wherein a part of a spring made of a conductive material is brought into contact with a bearing of a capstan shaft and the other part is attached to a motor of the motor. Tape recorder characterized by being in contact with a plate