JPS6131679B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a vibration system in which a magnetic vibrator is provided at the other end of a cantilever having a needle tip at its tip, and the magnetic vibrator is supported so as to be movable in angle;
It has a magnetic space in which a magnetic resonator constituting the vibration system is arranged, and a power generation system that is magnetically coupled to the vibration system, and when the magnetic resonator moves angularly in the magnetic space, the power generation system is generated. This relates to a movable magnet type pick-up cartridge configured to extract the starting force from a power generating coil installed in the system. An object of the present invention is to provide an excellent movable magnet type pickup cartridge capable of extracting reproduction output.

In general, most movable magnet type pick-up cartridges are of the needle exchange type, and as shown in Fig. 1, the cartridge body 4 is equipped with a replacement needle 2 equipped with a vibration system 1, and a power generation system 3 to which the replacement needle 2 is attached.
It is composed of Here, the replacement needle 2 is provided with a magnetic vibrator 7 at the other end of a cantilever 6 having a needle tip 5 at its tip.
is held in a cylindrical holder 8 made of a non-magnetic material so as to be movable angularly by a damper 9 made of a viscoelastic material disposed within the holder 8. The vibration system 1 is integrally constructed with a knob 10. On the other hand, the cartridge body 4 has U-shaped cores 11 and 12 made of magnetic material, each of which is wound with generating coils 13A, 13B, 14A, and 14B, and the tips of these cores 11 and 12 are arranged in opposite directions. Yoke part 1
5A, 15B and 16A, 16B are arranged facing each other in the direction of the maximum sensitivity axis of the 45°-45° method,
A power generation system 3 with a magnetic space formed therein is constructed in a shield case 17 made of a non-magnetic material, and the replacement needle 1 has a holder 8 constituting it on the front side of the cartridge body 4. The magnetic vibrator 7 is inserted through the provided mounting hole 18 and held within the holder 8, and is attached to the yoke portion 15.
The tip 5 of the cantilever 6 constituting the vibration system 1 is attached so as to be placed in the magnetic space formed in the corresponding spaces of A, 15B and 16A, 16B.
When the record surface 19 is traced by the cantilever 6, the magnetic oscillator 7 provided at the other end of the cantilever 6 vibrates and changes the magnetic flux flowing through the cores 11 and 12 that constitute the power generation system 3.
The generating coil 13A, 1 wrapped around the outer circumference of 1, 12
The configuration was such that an electromotive force was generated at 3B, 14A, and 14B. However, in the movable magnet type pickup cartridge configured as described above, the magnetic vibrator 7 constituting the vibration system 1 is connected to the yoke portions 15A, 15B and 16 constituting the power generation system 3.
The vibration fulcrum 20 of the vibration system 1 is disposed in a magnetic space formed by A and 16B, and the magnetic space exists within the cartridge body 4.
(In this case, the intersection point between the center line of the damper 9 and the center axis of the magnetic vibrator 7) is necessarily located inside the cartridge body 4, and the length of the cantilever 6 constituting the vibration system 1 is If an attempt is made to reduce the mass of the vibration system 1 itself by shortening the length, the distance between the record surface 19 and the vibration fulcrum 20 will become shorter, and the cartridge body 4 will come into contact with the record surface 19, which will affect the playback characteristics, i.e. There were naturally limits to improving the reproduction frequency characteristics in high frequency bands. That is, in the case of the above-mentioned movable magnet type pick-up cartridge, since the vibration fulcrum 20 of the vibration system 1 is located inside the cartridge body 4, if the length of the cantilever 6 is to be shortened, its vertical tracking angle will be reduced. Since the distance between the record surface 19 and the vibration fulcrum 20 must be maintained by increasing the depth, even if the reproduction frequency characteristics in a high frequency band can be improved, the reproduction output will contain a lot of distortion. In order to maintain the vertical tracking angle of the cantilever 6 at an ideal angle and obtain a reproduced output with little distortion, the length of the cantilever 6 must naturally be increased, and the reproduction frequency characteristics in a high frequency band The disadvantage was that it worsened the situation.

The present invention solves these conventional drawbacks by attaching a magnetic oscillator to the other end of a cantilever having a needle tip at its tip, supporting this magnetic oscillator so that it can be angularly movable, and controlling the magnetic vibration. A replacement needle has a vibration system with a vibration fulcrum placed near the sensor, and this replacement needle is removably attached, and a plurality of yokes are arranged inside to face each other in the direction of the maximum sensitivity axis of the 45°-45° method. The cartridge body forms a magnetic space to which the vibration system is coupled, and houses a power generation system in which a power generation coil is wound around a core magnetically coupled to these yokes. The effective magnetic space for the vibration system of the housed power generation system is arranged outside the cartridge main body, and when the replacement needle is attached to the cartridge main body, the magnetic vibrator constituting it is The vibration system is arranged in an effective magnetic space drawn out of the cartridge body so as to be magnetically coupled to the power generation system housed within the cartridge body, and the vibration system It includes a plurality of auxiliary yokes that are arranged facing each other in the direction of the maximum sensitivity axis of the 45°-45° method so as to surround the outer periphery of the magnetic vibrator, and the exchange needle that makes up this vibration system is connected to the power generation system. When mounted on a cartridge body housing a cartridge, each of a plurality of yokes constituting the power generation system is circumscribed to each of a plurality of auxiliary yokes provided in the vibration system outside or within the cartridge body, and the power generation system is The present invention is characterized by a configuration in which an effective magnetic space is formed in a space facing the auxiliary yoke at a position outside the cartridge main body.

With the above configuration, the present invention can draw out a substantial magnetic space to the outside of the cartridge body, so the length of the cantilever itself can be shortened, and by providing an auxiliary yoke in the vibration system, high reproducibility can be achieved. This allows the output to be taken out.

The present invention will be described below with reference to drawings of embodiments.

FIGS. 2 and 4 show an embodiment of the movable magnet type pick-up cartridge of the present invention, and in the figures,
21 is a replacement needle equipped with a vibration system 22, and 23 is a cartridge body equipped with a power generation system 24 to which the vibration system 22 provided in the replacement needle 21 is magnetically coupled.
The vibration system 22 provided in the replacement needle 21 includes a magnetic vibrator 27 attached to the tip of a cantilever 26 having a needle tip 25 at the tip.
7 is the tip recess 2 of the holder 28 made of non-magnetic material.
8a and through hole 26b of this holder 28.
A support 30 is fixed in advance to the suspension wire 29 provided on the rear surface of the magnetic vibrator 27.
, and pull this support body 30 from the rear of the holder 28 to connect the suspension wire 29.
The magnetic vibrator 27 is supported within the recess 28a so as to be movable angularly by appropriately compressing the damper 31 inserted in advance and tightening the mounting screw 32 provided on the holder 30. A knob 33 is integrally formed on this vibration system 22. The tip of the holder 28 constituting the vibration system 22 is covered by a ring-shaped shield ring 34 made of a conductor or magnetic material and integrally provided with the knob 33. The magnetic vibrator 27 and the yoke portion of the power generation system 24, which are disposed in the tip recess 28a, are magnetically isolated from the outside. The cartridge main body 23 has a U-shaped core 35, 3 made of a magnetic material.
6 have power generation coils 37A, 37B and 38, respectively.
A, 38B are wound around the yoke portions 39A, 39B, 40A, 40 where the cores 35, 36 face each other.
A power generation system 24 in which B is arranged facing each other in the direction of the maximum sensitivity axis of the 45°-45° method is housed and fixed in a shield case 41 made of a magnetic material, and these yoke parts 39A, 39B and 40
A magnetic space 2 in which a magnetic vibrator 27 constituting the vibration system 22 is arranged at a location corresponding to A and 40B.
It is equipped with 4. Here, the cartridge main body 23 is provided with a square mounting window 44 on its front surface, into which a protrusion 43 provided on the rear surface of the replacement needle 21 is inserted.
yoke parts 39A, 39B and 40A,
40B is provided protrudingly. On the other hand, the replacement needle 21
On the rear surface, the yoke portions 39A, 39B and 40A protruding from the front surface of the cartridge main body 23 are provided.
A hole (not shown) into which the needle 40B is inserted is formed so as to surround the vibration system 22 provided in the replacement needle 21.

In such a configuration, when the replacement needle 21 is attached to the cartridge main body 23, the yoke portion 3 of the power generation system 24, which is provided on the cartridge main body 23 side and protrudes from the front surface of the cartridge main body 23, as shown in FIG.
A magnetic vibrator 27 constituting the vibration system 22 is provided on the exchange needle 21 side within the magnetic space 42 formed by 9A, 39B and 40A, 40B.
is placed. Therefore, when the stylus 25 at the tip of the cantilever 26 constituting the vibration system 22 traces the sound groove on the record surface 45, the magnetic oscillator 27 provided at the other end of the cantilever 26 vibrates, generating the electricity. By changing the magnetic flux flowing through the yoke and core that make up the system 24, the core 35,
Generating coils 37A, 37B, 38 wound around 36
An electromotive force is generated at A and 38B. Moreover, while maintaining the vertical tracking angle of the cantilever 26 constituting the vibration system 22 at an ideal angle, the vibration fulcrum 46 of the vibration system 22 (in this case, the center of gravity of the magnetic vibrator 27) 46 and the record surface 4
Even if the distance between the cartridge main body 23 and the record surface 45 is shortened, a sufficient distance can be maintained between the cartridge main body 23 and the record surface 45. In other words, the effective magnetic space 42
Since the cantilever 26 can be brought close to the needle tip 25 and the magnetic resonator 27 can be placed in the magnetic space 42 so as to be able to move angularly, the length of the cantilever 26 itself is shortened. It is possible to obtain a reproduction output with less distortion by improving reproduction frequency characteristics.

Further, as shown in the figure, a part of the holder 28 is replaced with a magnetic material, so that the magnetic vibrator 27 constituting the vibration system 22 and the power generation system 24
yoke parts 39A, 39B and 40A,
40B is magnetically coupled to the outside of the cartridge main body 23, the degree of magnetic coupling can be made stronger, and the reproduced output output can be increased. In this case, the vibration system 22 is provided with a cylindrical spacer sleeve 47 made of a non-magnetic material at the tip of the holder 28 constituting the vibration system 22, and the outer circumference of the spacer sleeve 47 is set at a angle of 45 degrees.
Auxiliary yoke parts 48, 49 in the form of strips made of magnetic material are attached to each of the slits 47a to 47d, which are provided facing each other in the direction of the maximum sensitivity axis of the 45° method.
50 and 51 are fixed to form a circular arc shield ring 34.
and respective yoke portions 39 constituting the power generation system 24 which are integrally formed with the knob 33 and protrude from the front surface when attached to the cartridge main body 23.
A, 39B and 40A, 40B may be made to circumscribe each of the auxiliary yoke parts 48, 49, 50, 51. With this configuration, the vertical tracking angle of the cantilever 26 constituting the vibration system 22 can be maintained at an ideal angle, and the distance between the lowest surface of the cartridge body 23 and the record surface 45 can be maintained at an appropriate level. Since the cantilever 26 itself can be shortened, it is possible to improve reproduction frequency characteristics in a high frequency band and to output reproduction output with less distortion.
In addition, the auxiliary yokes 48 to 48 provided in the vibration system 22
51 serves as an effective magnetic transmission section, and the magnetic loss gap made of non-magnetic material, which leads to a decrease in reproduction output, is reduced, so the magnetic resonator 27 can be made smaller. Since the auxiliary yokes 48 to 51 fill the reduced portion with magnetic coupling surfaces, it is possible to construct a vibration system with extremely light mass as a result, and it is possible to increase the output of the reproduced output signal. . Furthermore, the separation characteristics in stereo reproduction are determined by the auxiliary yoke 4 provided with the vibration system 22.
The replacement needle 21 is uniquely determined by 8 to 51.
The separation characteristics are not deteriorated when replacing them, and variations thereof can be minimized.

5 to 7 show other embodiments of the movable magnet type pick-up cartridge of the present invention, in which 1
21 is a replacement needle equipped with a vibration system 122, and 123 is a cartridge body equipped with a power generation system 124 to which the vibration system 122 provided in the replacement needle 121 is magnetically coupled. The replacement needle 121 is connected to the vibration system 122.
is integrated into the knob 133 together with a circular arc-shaped shield ring 134 made of a conductor or magnetic material. The vibration system 122 has a needle tip 125 at the tip.
A disc-shaped magnetic resonator 127 is attached to the tip of a cantilever 126 having Suspension wire 1 provided on the rear surface of the magnetic vibrator 127 in the through hole 128b.
29 is inserted in advance, and this support 130 is pulled from behind the holder 128, and the disc-shaped damper 131, which has been inserted in advance through the suspension wire 129, is moderately compressed. By tightening a mounting screw 132 provided on the holder 130, the magnetic vibrator 127 is supported in the recess 128a so as to be able to swing. The holder 128 constituting the vibration system 122 has a cylindrical spacer sleeve 120 made of a non-magnetic material, and a cylindrical spacer sleeve 120 that is made of a non-magnetic material.
A rectangular auxiliary yoke 11 made of a magnetic material is fixed in slits 120a to 120d, which are provided facing each other in the direction of the maximum sensitivity axis of the 45°-45° method.
9, 118, 117, and 116 constitute a cylindrical body, and by inserting and fixing this cylindrical body into a stepped portion provided around the outer periphery of the holder 128, the magnetic vibrator 127 is attached to the tip of the cylindrical body. and damper 1
31 is formed with a recess 128a for attachment. The vibration system 122 is integrated with the knob 133, and the auxiliary yokes 116 to 11 that make up the knob 133 are integrated with each other.
9 and the magnetic vibrator 127 are connected to the knob 13.
A circular arc-shaped shield ring 13 integrally formed with 3.
4 and is shielded from external magnetic fields. The cartridge main body 123 has U-shaped cores 135, 136 made of magnetic material, and power generating coils 137A, 137B and 138, respectively.
A, 138B are wound, and those cores 135, 13
6 opposing yoke parts 139A, 139B, 1
A power generation system 124 in which 40A and 140B are arranged facing each other in the direction of the maximum sensitivity axis of the 45°-45° method.
are housed and fixed in a shield case 141 made of magnetic material, and these yoke portions 13
A magnetic space 14 where the vibration system 122 is coupled to corresponding locations of 9A, 139B and 140A, 140B.
It is equipped with 2. Here, the cartridge main body 123 has a square mounting window 14 on its front surface through which a projection 143 provided on the rear surface of the replacement needle 121 is inserted.
4, and this mounting window 144 has yoke parts 139A and 139 that constitute the magnetic circuit 124.
B, 140A, and 140B.

In such a configuration, when the replacement needle 121 is attached to the mounting window 144 of the cartridge main body 123, the replacement needle 121 is inserted through the mounting window 144 of the cartridge main body 123 as shown in FIG.
A power generation system 124 is provided inside the cartridge main body 123, into which a vibration system 122 protruding from the rear surface is inserted.
It is arranged in a magnetic space 142 that constitutes a magnetic field. Each of the auxiliary yokes 116 to 119 fixed to the outer periphery of the holder 128 constituting the vibration system 122 serves as the yoke portion 13 constituting the magnetic circuit 124.
9A, 139B, 140A, and 140B, and the vibration system 122 is in contact with the cartridge body 1 in the cartridge body 123.
It is magnetically coupled to a power generation system 124 housed within 23. Here, the magnetic coupling between the power generation system 124 provided in the cartridge main body 123 and the auxiliary yokes 116 to 119 provided in the vibration system 122 is simply a coupling of magnetic circuits when viewed from the perspective of the entire movable magnet type pickup cartridge. First, substantial magnetic coupling between the magnetic circuit and the vibration system constituting the movable magnet type pickup cartridge is performed outside the cartridge body 123. In other words, the magnetic resonator 127 that constitutes the vibration system 122
is an auxiliary yoke 1 coupled to the magnetic circuit 124 and disposed outside the cartridge body 123;
16 to 119. Therefore,
Cantilever 126 that constitutes the vibration system 122
When the stylus 125 at the tip of the cantilever traces the sound groove on the record surface 145, the cantilever 125
The magnetic vibrator 127 provided at the other end vibrates to generate power generation system 1 including the auxiliary yokes 116 to 117.
By changing the magnetic flux flowing through the core 135,1
Generation coils 137A, 137B wrapped around 36,
An electromotive force is generated at 138A and 138B. When the vibration system 122 having the auxiliary yokes 116 to 119 is attached to the replacement needle 121 in this way, the vibration system 1
While maintaining the vertical tracking angle of the cantilever 126 constituting the oscillator 22 at an ideal angle, the vibration between the vibration fulcrum 146 of the vibration system 122 (in this case, the center of gravity of the magnetic oscillator 127) 146 and the record surface 145 is Even if the distance is shortened, a sufficient distance can be maintained between the cartridge body 123 and the record surface 145. In other words, since the effective magnetic space can be brought closer to the needle tip 125 side, the length of the cantilever 126 itself becomes extremely short, and as shown in FIG. 8, the reproduction frequency characteristics in the high frequency band are improved. This allows you to output playback output with less distortion. In Figure 8,
Curve A shows the frequency characteristics of the conventional movable magnet type pickup cartridge, and curve B shows the frequency characteristics of the movable magnet type pickup cartridge in this example.As is clear from these comparisons, the conventional example shows the frequency characteristics of the moving magnet type pickup cartridge. Although undulations are seen near the upper limit of 20KHz, in this example, flat characteristics can be obtained up to a high frequency band around 50KHz.
In addition, the auxiliary yoke 11 provided in the vibration system 122
6 to 119 serve as effective magnetic transmission parts, and the magnetic loss gap made of non-magnetic material that leads to a reduction in reproduction output is reduced, so the magnetic resonator 127 can be made smaller, and
Since the auxiliary yokes 116 to 119 can fill the small portion of the magnetic resonator 127 with a magnetic coupling surface, it is possible to construct a vibration system with an extremely light mass as a result, and the reproduced output signal It is possible to achieve high output. In addition, since the vibration system 122 provided thereon in the replacement needle 121 is coupled to the power generation system 124 within the cartridge body 123, the yoke portions 139A, 139B, 140A, 140B forming the power generation system 124 are connected to the vibration system 122 provided therein.
It is unlikely to cause damage to the Furthermore, the separation characteristics of stereo reproduction are determined by the auxiliary yokes 116 to 119 near the magnetic resonator 127.
These auxiliary yokes 116 and 117, and 118 and 11
Optimum separation characteristics can be obtained simply by arranging 9s facing each other in the direction of the maximum sensitivity axis of the 45°-45° system. In other words, in the conventional type, the separation characteristics are determined only after the needle vibrating part side and the power generating part side are combined.
Many variations occur in the serration characteristics depending on the combination of the needle vibrating part side and the power generation part side, but in this example, the needle vibrating part side has an auxiliary yoke that determines its performance. By manufacturing the vibrating part with high precision, the separation characteristics do not deteriorate when changing the needle, and variations thereof can be minimized.

Note that the auxiliary yokes 116 to 119 are the shield case 141 of the power generation section of the cartridge main body 123.
It is possible that the S/N deteriorates due to externally induced hum because the coils 137A, 137B, 138A, 138 protrude further to the outside, but the direct cause of the deterioration of the S/N is that the coils 137A, 137B, 138A, 138
This is due to the guidance of jumping into B, and by providing the auxiliary yokes 116 to 119, the deterioration of the S/N is negligible. As a countermeasure against these S/N deteriorations, the auxiliary yoke 116~
This can be improved by providing a shield ring 134 on the outer periphery of 119.

By bringing the effective magnetic circuit closer to the needle tip 125 in this way, it is possible to make it extremely lightweight.
The effective mass seen from the stylus tip can be set to a significantly smaller value, and while maintaining the same distance between the record surface and the bottom surface of the cartridge body, it is possible to achieve ultra-high performance frequency characteristics and high output. Furthermore, it is possible to provide an ideal movable magnet type pick-up cartridge that does not change the separation characteristics when changing needles.

As described above, according to the present invention, a magnetic circuit is provided in which yokes are arranged facing each other in the direction of the maximum sensitivity axis of the 45°-45° type, and a generating coil is wound around a core that is magnetically coupled to these yokes. It comprises a stored cartridge body and a vibration system that supports a magnetic vibrator installed at the other end of a cantilever having a needle tip at its tip so as to be able to move angularly within the magnetic space of a magnetic circuit provided in the cartridge body. The vibration system includes an auxiliary yoke coupled to the yoke so as to surround the outer periphery of the magnetic vibrator, and an effective magnetic yoke that pulls out the magnetic vibrator constituting the vibration system to the outside of the cartridge body. Because they are arranged in space, the vertical tracking angle of the cantilevers that make up the vibration system remains at an ideal angle even if the vibration fulcrum near the magnetic vibrator that makes up the vibration system is close to the record surface. This makes it possible to maintain a sufficient distance from the bottom surface of the cartridge body to the record surface, and therefore the length of the cantilever itself can be shortened, greatly improving the playback frequency characteristics up to high frequency bands. It has excellent advantages such as being able to improve playback performance and producing high reproduction output with little distortion.

Moreover, since the present invention provides an auxiliary yoke for configuring the magnetic circuit on the exchange needle side, the vibrator system part can be designed more compactly, and a high-performance vibrator with a small effective mass can be realized. The yoke side having the yoke can be enlarged, and as a result, a highly efficient power generation unit can be constructed.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a conventional movable magnet type pick-up cartridge, Fig. 2 is a cross-sectional view showing an embodiment of the movable magnet type pick-up cartridge of the present invention, and Fig. 3 is an enlarged cutaway perspective view of the main parts thereof. , FIG. 4 is an assembled perspective view of the main parts thereof, FIG. 5 is a sectional view showing another embodiment of the movable magnet type pickup cartridge of the present invention, FIG. 6 is an enlarged cutaway perspective view of the main parts, and FIG. FIG. 7 is an assembled perspective view of the main parts thereof, and FIG. 8 is a comparative characteristic curve diagram of the frequency characteristics of the movable magnet type pickup cartridge of the present invention and a conventional movable magnet type pickup cartridge. 21,121...Replacement needle, 22,122...Vibration system, 23,123...Cartridge body, 24,1
24...Power generation system, 25,125...Needle tip, 26,12
6... Cantilever, 27, 127... Magnetic resonator, 128... Holder, 31, 131... Damper, 34, 134... Shield ring, 35, 3
6,135,136...Core, 37A, 37B, 3
8A, 38B, 137A, 137B, 138A,
138B...Generating coil, 39A, 39B, 40
A, 40B, 139A, 139B, 140A, 1
40B...Yoke, 41,141...Shield case, 41,142...Magnetic space, 46,146...Vibration fulcrum, 47,120...Spacer sleeve, 48
~51,116~119...Auxiliary ring.

Claims (1)

[Claims] 1. A vibration device in which a magnetic vibrator is attached to the other end of a cantilever having a needle tip at the tip, the magnetic vibrator is supported so as to be able to move angularly, and a vibration fulcrum is arranged near the magnetic vibrator. A magnetic space in which the replacement needle is removably attached, a plurality of yokes are arranged facing each other in the direction of the maximum sensitivity axis of the 45°-45° method, and the above-mentioned vibration system is coupled. and a cartridge body housing a power generation system in which a power generation coil is wound around a core magnetically coupled to these yokes, and the cartridge body houses the vibration system of the power generation system housed inside the cartridge body. The effective magnetic space for the replacement needle is arranged outside the cartridge body, and when the replacement needle is attached to the cartridge body, the magnetic vibrator constituting it is pulled out to the outside of the cartridge body. The vibration system is arranged in an effective magnetic space so as to be magnetically coupled to the power generation system housed in the cartridge main body, and the vibration system has an outer periphery of a magnetic oscillator that constitutes the vibration system. It includes a plurality of auxiliary yokes that surround each other in the direction of the maximum sensitivity axis of the 45°-45° method, and when the replacement needle that makes up this vibration system is attached to the cartridge body that houses the power generation system. Each of the plurality of yokes constituting the power generation system is circumscribed outside the cartridge body to each of the plurality of auxiliary yokes provided in the vibration system, and an effective magnetic space constituting the power generation system is formed outside the cartridge body. A movable magnet type pick-up cartridge, characterized in that the movable magnet type pick-up cartridge is formed in a space facing the auxiliary yoke in a horizontal position. 2. A replacement needle having a vibration system in which a magnetic oscillator is attached to the other end of a cantilever having a needle tip at the tip, the magnetic oscillator is supported so as to be movable in angle, and a vibration fulcrum is arranged near the magnetic oscillator. This replacement needle is detachably attached, and a plurality of yokes are disposed inside facing each other in the direction of the maximum sensitivity axis of the 45°-45° method to form a magnetic space to which the above-mentioned vibration system is coupled. a cartridge body housing a power generation system having a power generation coil wound around a core magnetically coupled to a yoke; the cartridge body has an effective magnetic field for the vibration system of the power generation system housed therein A space is arranged outside the cartridge body, and when the replacement needle is attached to the cartridge body, an effective magnetic space is formed in which a magnetic vibrator constituting the exchange needle is pulled out outside the cartridge body. The vibration system is arranged at an angle of 45 degrees so as to surround the outer periphery of the magnetic vibrator that constitutes the vibration system. It includes a plurality of auxiliary yokes arranged in the direction of the maximum sensitivity axis of the -45° method, and when the replacement needle that makes up this vibration system is attached to the cartridge body that houses the power generation system, the plurality of auxiliary yokes provided in the vibration system Each of the plurality of yokes constituting the power generation system is circumscribed within the cartridge main body by each of the auxiliary yokes, and the effective magnetic space constituting the power generation system is located opposite the auxiliary yokes at a position outside the cartridge main body. A movable magnet type pick-up cartridge characterized by being formed in a space. 3 The plurality of auxiliary yokes are each independently formed into a strip shape, and the maximum angle of 45°-45° around the outer periphery of the cylindrical body for supporting the magnetic vibrator constituting the vibration system so as to allow angular movement. 2. The movable magnet type pickup cartridge according to claim 1, wherein the movable magnet type pickup cartridge is inserted into and fixed in slits provided oppositely in the direction of the sensitivity axis. 4. The movable magnet type pickup cartridge according to claim 1, wherein a shield ring is formed on each exchange needle so as to surround the effective magnetic space of the power generation system for the vibration system provided in each exchange needle. 5 The plurality of auxiliary yokes are each independently formed into a strip shape, and the maximum angle of 45°-45° around the outer periphery of the cylindrical body for supporting the magnetic oscillator constituting the vibration system so as to allow angular movement. 3. The movable magnet type pickup cartridge according to claim 2, wherein the movable magnet type pickup cartridge is inserted and fixed into slits provided oppositely in the direction of the sensitivity axis. 6. The movable magnet type pickup cartridge according to claim 2, wherein the replacement needle is provided with a shield ring so as to surround the effective magnetic space of the power generation system for the vibration system provided therein.