JPS5941680Y2 - Pickup Cartridge - Google Patents

Description

[Detailed description of the invention] The present invention is a cartridge of the type that picks up signals by an electret, in particular, a needle tip is attached to the free end of a cantilever that protrudes outside from a hole in a shield plate, and a pick-up point is attached adjacent to the needle tip. This invention relates to an improvement in a pickup cartridge equipped with an electret.

Since the pickup cartridge of the above-mentioned type is configured to directly utilize the vibration of the needle tip, the rigidity of the cantilever is not an issue, and the use of a material such as plastic that not only can reduce the cross section of the cantilever but also has a relatively small mass can be used. This has the advantage that the effective mass of the stylus tip can be made extremely small, and distortion caused by mechanical vibration can be significantly eliminated, resulting in high-fidelity reproduced sound.

However, the edge of the cantilever protruding from the hole in the shield plate is 3600 mm when viewed from the top, bottom, left and right, that is, from the front.
Approximately 1.51! In order to create a structure that can move freely in an amount of about 200 yen, there is a drawback that dust, etc. can enter the interior through the holes in the shield plate and be absorbed by the pickup electret, degrading its performance.To prevent this, It was difficult to completely seal against the intrusion of dust and the like.

The purpose of this invention is to make the holes in the shield plate into a special shape, that is,
Therefore, according to the present invention, as shown in the drawings, the cantilever 3 protrudes outward from the hole 2 of the shield plate 1. In a pickup cartridge in which a pickup electret 7 is attached adjacent to a needle tip 6 attached to a free end 5 on the opposite side of the fulcrum portion 4, the pickup electret 7 is attached to a needle tip 6 attached to a free end 5 on the opposite side of the fulcrum portion 4. The bottom outer periphery 9 of the dustproof horn-shaped seal piece 8 made of a flexible elastic material is fixed to the periphery of the hole 2 of the shield plate 1 with a suitable adhesive, and the horn-shaped seal piece 8 is placed inside the shield plate 1. The cantilever 3 is inserted into the cavity 10 of the horn-shaped seal piece 8, thereby sealing the shield plate 1 to prevent dust from entering through the hole 2 of the shield plate 1.

According to the present invention, as described above, the hole 2 of the shield plate 1 is closed with the flexible horn-shaped seal piece 8 made of an elastic material, and the cantilever 3 is inserted into the cavity of the seal piece. It is possible to reliably seal between the hole and the cantilever without affecting minute movements of the cantilever in a freely movable state.

[Brief explanation of the drawing]

FIG. 1 is a route diagram of a pickup cartridge according to the present invention, and FIG. 2 is an enlarged longitudinal sectional view of a horn-shaped seal piece. 1...shield plate, bar, 4...fulcrum, 2...hole, 3...cantilever 5...
... Free end, 6 ... Needle tip, 7 ... Electret for pickup, --shaped seal piece. 8...Ho

Claims (1)

[Scope of utility model registration request] In a pickup cartridge, in which a needle tip is attached to the free end of a cantilever that protrudes outside from a hole in the shield plate, and a pickup electret is provided adjacent to the needle tip, the hole is connected to a horn-shaped "horn" made of a flexible material. A pickup cartridge, characterized in that it is closed with a seal piece, and the cantilever is inserted into the cavity of the seal piece.