JPS5842540B2 - record player - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an O1-IJ turn type record player, and more particularly to an auto-return user gear that can reliably complete the auto-return operation.

First, an outline of an auto-return mechanism configured to detect the moving speed of the tone arm and start an auto-return operation will be explained with reference to FIG.

FIG. 1 is a flat cylindrical view showing a turntable drive shaft and an auto-return gear.

Reference numeral 1 denotes an auto-return gear, which rotates around a shaft 2.

A portion of the outer periphery of the large gear 1 is provided with a toothless portion 1a.

Furthermore, a heart-shaped cam 1b is formed on the lower surface of the large gear 1, and when the large gear 1 rotates, this heart-shaped cam 1b
Auto-return sliding member 9 that can be slid linearly at
In response to the displacement of the tone arm (not shown), the tone arm (not shown) returns toward the armrest (see FIG. 2).

Two trigger levers 3 and 3' are arranged on the top surface of the large gear 1, and when the tone arm starts scanning the silent groove of the record, the trigger levers are moved in relation to the rotation of the tone arm. 3' is rotated counterclockwise about the shaft 4, and this rotation causes the trigger lever 3 placed thereon to rotate.
The trigger lever 3 is also rotated counterclockwise as a result of the friction.

A small gear 6 is fitted onto the turntable drive shaft 5, and this shaft 5 has a starting pawl 7 that engages with the trigger lever 3.

For the first time, during record derivation, the toothless portion 1a of the large gear 1 faces the small gear 6, and the two gears do not engage with each other, and the starting pawl 7 and the trigger lever 3 are folded. The bent portion 3a also does not engage with the capillary.

When the tone arm begins to scan the end of the sound groove of the record, the movement of the tone arm is transmitted to the trigger lever 3', and the trigger levers 3 and 3' are gradually rotated counterclockwise. .

And when the tone arm starts scanning the silent groove,
Trigger levers 3 and 3' rotate significantly counterclockwise.

Then, the bent portion 3a of the trigger lever 3 engages with the starting pawl 7, causing the large gear to rotate slightly.Then, the top gear 1 and the small gear 6 mesh with each other, and the large gear 1 starts rotating.

As is well known, when the large gear 1 rotates, the follower pin 9a comes into contact with the heart-shaped cam 1b provided on the lower surface of the large gear 1.
The O1-IJ turn sliding member 9 having an O1-IJ turn is slidably displaced, and in response to the displacement of the sliding member 9, an auto-return operation of the tone arm is performed.

While the large gear 1 rotates once, the trigger levers 3 and 3'
It is returned to the initial position shown in the figure.

Then, when the toothless portion 1a of the large gear 1 and the small gear 6 come to face each other again, the meshing relationship between both gears is released and the auto-return operation is completed.

The operation of rice immediately before the auto-return operation ends will be described with reference to FIG. 3.

In the conventional auto-return manual gear, tooth 10 is the final tooth, and there was no incomplete tooth 11, which is the gist of the present invention.

Now, assuming that the mesh between the teeth 10 and the small gear 6 is released,
At this point, as shown in FIG. 2, since the follower pin 9a is near the tip of the heart-shaped cam 1b, the spring 9b
The follower pin 9a falls into the tip of the heart-shaped cam 1b due to the elastic force of the cam 1b.

That is, when the mesh with the small gear 6 is released, the large gear 1 does not immediately stop rotating, but rotates slightly (distance a) due to the elastic force of the spring 9b and reaches approximately the center of the toothless portion 1a of the large gear 1. Rotation is stopped when the small gear 6 is positioned.

However, immediately after the meshing between the large gear 1 and the small gear 6 is released, the trigger lever 3 rotates counterclockwise due to the shock generated when the large gear 1 rotates by a distance a, and the trigger lever 3 rotates counterclockwise. There was a concern that the bent portion 3a of the trigger lever 3 would engage with the large gear 1 and the rotation of the large gear 1 would start again.

Therefore, in the present invention, an incomplete tooth 11 that is short in the radial direction is added in succession to the conventional tooth 10.

According to such a configuration, after the meshing between the large gear 1 and the small gear 6 is released, the distance that the large gear 1 rotates by the spring 9b is only b (b(a)), so the above-mentioned shock is significantly reduced. It is something that will be done.

In addition, if the incomplete tooth 11 is made into a complete tooth (see the broken line in Fig. 3), the distance between the complete tooth and the small gear 6 will be extremely close, and there is a risk that a slight shock will cause them to come into contact and cause noise. be.

According to the present invention described above, since the first tooth connected to the disengaged side of the missing tooth portion of the large gear is an incomplete tooth that is short in the radial direction, the large gear rotates once and automatically This prevents the inconvenience of the large gear starting the next rotation after the return operation is completed.

[Brief explanation of the drawing]

Figure 1 is a plan view showing the turntable drive shaft and the auto-return gear, Figure 2 is a back view showing the relationship between the auto-return gear and the auto-return sliding member, and Figure 3 is the auto-return according to the present invention. It is an enlarged view showing a servant gear. 1 is an auto-return service gear, 5 is a turntable drive shaft, 6 is a small gear, 1a is a missing tooth, and 11 is an incomplete tooth.

Claims (1)

[Claims] 1. A record player that performs an auto-return operation of a tone arm using an auto-return manual gear that starts rotating when it meshes with a small gear that rotates in conjunction with the rotation of a turntable drive shaft, the auto-return manual gear has a toothless part to release the meshing between the small gear and the large gear when playing a record, and the first tooth connected to the meshing release side of this toothless part is an incomplete tooth with a short height in the radial direction. Features a record player.