JP2018125650A - Cartridge capable of fixing coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a technique for making a cartridge itself correspondable to balance transmission.SOLUTION: A first coil fixing cartridge 10 includes a substantially columnar magnet 18 integrated with a cantilever 20 in the same axial direction, and arranged to be vibratable together with the cantilever 20, and a first pick-up coil 16 arranged fixedly in te vicinity of the magnet 18. The first pick-up coil 16 consists of N turns of a conductor 14, and a common line 26 is derived from a tap 24 in the center of the winding.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a coil fixed type cartridge.

As shown in FIG. 6, in the conventional coil fixed type cartridge 60, a cylindrical magnet 18 integrally attached to the base of the cantilever 20 can vibrate in the vicinity of the pickup coil 62, for example, around the ideal center point A. Is arranged.
A diamond needle 22 is fixed to the tip of the cantilever 20.

The magnet 18 has an N pole on one end face and an S pole on the other end face, and the pickup coil 62 is driven by the swing of the magnet 18 following the swing of the cantilever 20 from the solid line position to the dotted line position. A magnetic flux change occurs on the side, and this is taken out from both ends as output signals (see Patent Documents 1 and 2).
JP 52-53404 A Actual Kosho 59-38799

By the way, in the field of audio, it is recognized that a so-called balanced transmission system in which signals are exchanged using three cables, hot, cold, and ground, is effective in reducing noise.
However, since the conventional coil-fixed cartridge 60 does not support a balanced configuration, as shown in FIG. 7, a transformer 32 is installed between the differential amplifier 28 and the primary coil 32a and the secondary coil A configuration is adopted in which an intermediate point of the side coil 32b is taken out and grounded.
For this reason, the apparatus configuration has to be complicated.

  The present invention has been devised to solve such a conventional problem, and an object thereof is to realize a technique that enables the cartridge itself to support a balanced transmission system.

In order to achieve the above object, a coil-fixed cartridge according to the present invention includes a substantially cylindrical magnet that is integrated with a cantilever with the same axial direction and is arranged to vibrate with the cantilever, and the vicinity of the magnet. The pickup coil is provided with a pickup coil fixedly arranged, and the pickup coil is formed by winding a conductive wire N times, and a common line is derived from the winding center portion.
The common line is derived from, for example, a tap provided at the center of the winding of the pickup coil.
Alternatively, a pair of conductive wires can be overlapped and wound, the terminal portion of one conductive wire and the starting end portion of the other conductive wire can be connected, and the common line can be derived from this connecting portion.

  In the case of the coil fixed type cartridge according to the present invention, since the common line is led out from the winding center portion of the pickup coil, by connecting this to the ground, it becomes possible to cope with the balance type transmission method with the cartridge alone, While having a simple configuration, the noise reduction effect can be sufficiently exhibited.

  FIG. 1 shows the internal structure of a first fixed coil type cartridge 10 according to the present invention. An air core first pickup coil 16 in which a conductive wire 14 is wound N times, a cylindrical magnet 18, A cantilever 20 integrated with a magnet 18 is provided.

The magnet 18 and the cantilever 20 are arranged and fixed in the coaxial direction.
A diamond needle 22 is fixed to the tip of the cantilever 20.
The magnet 18 is held in a freely vibrating manner by an elastic material (not shown) such as a steel wire.
A tap 24 is provided at an intermediate portion (1 / 2N turns) of the winding of the first pickup coil 16, and a common line 26 is connected thereto.

As shown in FIG. 2, by grounding the common line 26, the first coil fixed type cartridge 10 itself can be made to be a balance transmission compatible type.
Therefore, it is possible to effectively reduce noise without providing a balance-compatible transformer between the differential amplifier 28 as in the prior art.
Further, by directly connecting the pickup coil 16 to the differential amplifier 28 in this way, the configuration can be simplified.
Reference numeral 30 in the figure indicates a tone arm.

However, as shown in FIG. 3, the first coil fixed type cartridge 10 and the balanced transmission compatible transformer 32 may be used in combination.
Thus, by interposing the transformer 32 having a structure in which the intermediate point between the primary side coil 32a and the secondary side coil 32b is grounded between the first coil fixed type cartridge 10 and the differential amplifier 28, the cartridge itself And in the transformer 32, there is an advantage that noise can be removed twice.

FIG. 4 shows an example of use of the second fixed coil cartridge 50 according to the present invention.
The second coil fixed type cartridge 50 is characterized in that it includes a second pickup coil 52, and the other configuration is not different from the first coil fixed type cartridge 10.

FIG. 5 is a conceptual diagram showing the configuration of the second pickup coil 52. As shown in the figure, the first conductor 54 and the second conductor 56 are overlapped (bundled) and wound with an air core, and the terminal 54a of the first conductor 54 and the second conductor 56 are connected to each other. The start end portion 56a is connected.
A common line 60 for ground connection is derived from the connection point 58.

Therefore, the cartridge itself can be balanced, and noise can be effectively reduced without providing a balanced transformer 32 between the differential amplifier 28 as in the prior art.
Although not shown, the second coil fixed type cartridge 50 and the balance-compatible transformer 32 can be used in combination as described above.

  For convenience of illustration, an example in which one pickup coil is provided in the cartridge has been described above. However, by arranging two pickup coils at a predetermined angle (for example, 90 degrees) around the axis of the magnet 18. Of course, a cartridge corresponding to a stereo is also possible.

It is a conceptual diagram which shows the structure of the 1st coil fixed type cartridge which concerns on this invention. It is a circuit diagram which shows the usage example of a 1st coil fixed type cartridge. It is a circuit diagram which shows the other usage example of a 1st coil fixed type cartridge. It is a circuit diagram which shows the usage example of a 2nd coil fixed cartridge. It is a conceptual diagram which shows the structure of a 2nd pickup coil. It is a conceptual diagram which shows the structure of the conventional coil fixed type cartridge. It is a circuit diagram which shows the usage example of the conventional coil fixed cartridge.

10 First coil fixed type cartridge
14 conductor
16 First pickup coil
18 Magnet
20 Cantilever
22 Diamond needle
24 taps
26 Common line
28 Differential Amplifier
30 tone arm
32 Balance transmission compatible transformer
50 Second coil fixed type cartridge
52 Second pickup coil
54 First conductor
54a End of first conductor
56 Second conductor
56a Start of second conductor
58 Connection point between the end of the first conductor and the start of the second conductor
60 Common lines

Claims (3)

A substantially cylindrical magnet that is integrated with the cantilever in the same axial direction and is arranged to vibrate with the cantilever;
It has a pickup coil fixedly placed in the vicinity of this magnet,
This pick-up coil consists of a conductive wire wound N times, and a common wire is derived from the winding center part.   The coil fixed type cartridge according to claim 1, wherein a tap is provided in the center of the winding of the pickup coil, and the common line is led out therefrom.   The pair of conductive wires are overlapped and wound, the terminal portion of one conductive wire is connected to the starting end portion of the other conductive wire, and the common line is derived from the connecting portion. Coil fixed type cartridge.

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