JPS6037681Y2 - Linear tracking arm elevation mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an elevation mechanism for a linear tracking arm, and particularly to an arm elevation mechanism that uses a linear motor as an arm drive source or is suitable for a linear tracking arm assembly.

Linear tracking type tonearms move horizontally in a straight line, so their range of movement is large.
Therefore, there is a drawback that the elevation mechanism is complicated in order to raise and lower the tone arm at any point within the movement range.

Recently, a linear tracking arm that uses a linear motor instead of a rotary motor as an arm drive source has been developed.

This is because linear motors have advantages such as no vibrations, no need to use alternating current signals to drive them, and S/N deterioration can be prevented.

In a tone arm assembly using a linear motor, a movable base is provided that supports the tone arm and can slide freely along a predetermined guide rod, and a field pole made of a magnet is integrally attached to this movable base. A coil, which is disposed opposite the magnet with a predetermined gap therebetween, is wound around a magnetic material provided parallel to a predetermined guide bar to constitute an armature portion.

By passing current through the armature coil, the field pole facing the armature is moved along the armature, that is, along the guide rod, thereby causing the tone arm to track in the horizontal direction.

In addition to the disadvantage of the complexity of the elevation mechanism as described above, such tone arm assemblies have a structure in which the movable base that supports the arm only engages with the guide rod via rollers, so it is difficult to raise and lower the arm. When excessive force is applied, the movable base moves left and right, resulting in a so-called side-slip phenomenon.

Therefore, the purpose of the present invention is to provide an elevation mechanism for a linear tracking arm with a simple structure.
In particular, it is an object of the present invention to provide an elevation mechanism that can handle the unique side-slip phenomenon that occurs when a linear motor-driven tone arm moves up and down.

The present invention will be explained below with reference to the drawings.

FIG. 1 is a side view, partially in section, showing an embodiment of the present invention.

The tone arm 1 is supported by a pivot mechanism 2 so as to be rotatable in horizontal and vertical directions, and a weight 3 is attached to the rear end of the arm.

The arm pivot mechanism 2 is supported on a movable base 4, and the movable base 4 is configured to be slidable along a pair of horizontally mounted guide rods 5a, 5b.

That is, the roller 6 rotatably attached to the movable base 4
and 7 are engaged with guide rods 5a and 5b, respectively.

A magnet 8 constituting the field pole of the beam near motor is attached to the lower end of the movable base 4, and a pair of poles (N,
A pair of coils 9 and 10, which serve as armatures and are arranged opposite to each other with a predetermined gap between them, are fixed in parallel to the guide bars 5a and 5b.

These coils 9 and 10 are wound around a magnetic yoke,
The magnetic flux generated from the N pole of the magnet 8 connects the coil 9 and the S
The magnetic flux returning to the pole interlinks with the coil 10.

Therefore, by supplying a current of a predetermined direction and a predetermined value to the coils 9 and 10, a force is generated between the magnet 8 and the coil portion facing it, and the movable magnet is driven in a predetermined direction, resulting in tone. The arm 1 performs a linear tracking operation.

In the present invention, the movable table 4 is provided with an elevating member 11 that is slidably attached in the arm elevating direction (up and down direction), and the upper end of this elevating member 11 has a contact portion that abuts the tone arm 1. 11a is provided, and by making the abutting portion 11a a flat structure, the arm can be easily raised and lowered, and the raising and lowering member does not come off from the movable base 4.

A friction member such as rubber having a braking function with a large friction coefficient is attached to the lower end 11b of the elevating member 11, and a spring 12 is installed in the hollow formed between the main body of the elevating member 11 and the movable table 4 as shown in the figure. is provided.

On the other hand, a contact member 13 is attached to the outer circumferential surface of the guide rod 5a, which extends parallel to its longitudinal center axis and comes into contact with the lower end 11b of the elevating member 11. (See Figure 2).

As shown in FIG. 2, the guide rod is rotatably supported by a support plate 14 about its longitudinal center axis.
The rotation is performed by the plunger 15.

That is, the other end of a rotating arm 16 whose tip is connected to the plunger 15 and rotates clockwise is fixed to the guide rod 5a.

A spring 17 is provided in the middle of the rotating arm 16 to bias the arm 16 counterclockwise.

As shown in the figure, protruding pins 1a and 1b are provided along the central axis of the arm at the portion where the tone arm 1 contacts the lifting member 11. A V-shaped R11c is provided on the surface that comes into contact with 1b, and the structure is such that it prevents the arm 1 from swinging in the horizontal direction when it rises, and always maintains the so-called center alignment of the arm 1. .

In the structure shown in FIGS. 1 and 2, the plunger 1
5 is activated, the rotating arm 16 rotates clockwise (in FIG. 2) against the spring 17, causing the guide rod 5a to also rotate clockwise, as shown in FIG. As shown, the contact member 13 is in a state separated from the elevating member 11 of the movable base 4.

To this end, the tone arm 1 is lowered and the device is therefore in a play or stop state.

Next, when the plunger 15 is deactivated, the guide rod 5a
is biased counterclockwise (in FIG. 2) by the spring 17, and the contact member 13 moves the elevating member 11 upward, causing the tone arm 1 to rise. Return operation is possible.

At this time, since a friction member such as rubber is attached to the lower end 11b of the elevating member 11, the phenomenon of sideways sliding of the movable table when the arm is raised is suppressed.

When the plunger 15 is activated again, the guide rod 5a is again rotated clockwise (in FIG. 2), so that the elevating member 11 is lowered by the restoring force of the spring 12, causing the arm 1 to descend.

Also at this time, the rubber at the lower end 11b of the elevating member prevents the movable platform from sliding sideways.

Incidentally, instead of providing the friction member on the elevating member 11, a similar effect can be expected by attaching a friction member to at least the portion of the contact member 13 that contacts the elevating member.

As described above, according to the present invention, an abutment member is provided on the guide member for the linear movement of the linear tracking arm, and the guide member is configured to be rotatable, and the tone arm is moved by the rotation of the abutment member. Since it is a structure that allows the tone arm to be raised and lowered, its structure is simple, and it also has the advantage that it can easily suppress side slipping of the arm support when the tone arm is raised and lowered in the case of linear motor drive.

It is clear that the structure of the above-mentioned embodiment shows only one example of the present invention and does not limit the present invention in any way.For example, the drive source for linear tracking is not limited to a linear motor structure; Of course, a motor may also be used.

[Brief explanation of drawings]

FIG. 1 is a side view, partially in section, showing an embodiment of the present invention, and FIG. 2 is a perspective view showing an example of a rotation drive mechanism for a guide rod. Explanation of symbols of main parts, 1... Tone arm,
4...Movable base, 5...Guide rod, 11
...Elevating member, 13...Abutment member, 1
5...Plunger.

Claims (3)

[Scope of utility model registration request] (1) An elevation mechanism for a linear tracking arm that raises and lowers a tone arm supported on a movable base while being guided by a guide member having a longitudinal central axis extending linearly, the guide member being rotatable. an elevating member attached to the movable base and having one end that can come into contact with the tone arm and swingable in the elevating direction of the arm; an abutting member extending parallel to the longitudinal central axis of the guide member over the range of movement of the arm and abutting the other end of the elevating member; and a driving means for rotating the guide member about the longitudinal central axis. An elevation mechanism for a linear tracking arm, comprising: (2) The elevation mechanism according to claim 1, wherein the other end of the elevating member is made of a friction member. (3) The elevation mechanism according to claim 1, wherein at least a portion of the abutting member that contacts the elevating member is made of a friction member.