JPS5824556Y2 - Pickup Cartridge - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a pickup cartridge with an improved magnetic circuit.

Conventional pickup cars) The magnetic circuit of IJ Tsuji, especially those that have a magnetic circuit installed parallel to the insertion hole of the pipe holder of the replacement needle, is divided into two coiled pole pieces and attached to one pole piece. After fitting the coil, the other pole piece is fitted to the coil and integrated.

However, it has been difficult to fix each pair of pole pieces fitted to the coil with the casing, that is, it has been difficult to fit the pole pieces into the holes into which the pipe holder is inserted.

This idea was made in view of the diagonal point.

The purpose of this is to fix the first pole piece to the base, which is divided into two parts, and to insert the coil fitted into the first pole piece, which is the second pole piece, and the pole piece formed on the base. By fitting into the groove, the first
To provide a pickup cartridge that can be fixed at an accurate position to a base that is a second pole piece.

Another object of the present invention is to place a shield plate on a base, form a pipe holder insertion part together with the base, and form a protrusion on the shield plate so that it can be inserted into the pipe holder. To provide a pickup cartridge which is brought into elastic contact and is grounded by being brought into contact with a case using a shield plate.

Next, an embodiment of this invention will be explained with reference to drawings.

A is a replacement needle, and there is a knob 1 made of resin that is attached to a shield case 11 of a cartridge body B, which will be described later, a pipe holder 2 that is fixed to the knob 1, and a magnet (not shown) inside the pipe holder. and y (elastically supported and fixed cantilever 3).

It consists of a regenerating needle 4 attached to the tip of the cantilever 3, and the above structure is well known.

The knob IK has a guide hole 1a into which a projection 5a2 protruding from the shield case 11 is inserted.

The cartridge body B includes a base 5 made of resin, and a shield plate 6 on which a horizontal piece 5bK of the base 5 is placed.

The first pole piece 7 on which the magnetic detection end of the vertical piece 5aK of the base 5 is molded, the coil 8 fitted into each of the pole pieces 7, and the long groove 5b1 of the base 5 between the coil 8°8' and the first pole piece 7. A pickup device comprising a second pole piece 9 that is inserted into the second pole piece 9.

A pedestal 10 provided with a terminal pin 12 for protecting the pickup device and leading the lead wire from the coil 8 to the outside. It also includes a shield case 11 made of a magnetically conductive material such as permalloy, into which the pickup device and the pedestal 10 are fitted.

Next, to explain the details of the structure of the pickup device, the base 5 is formed in an oval shape, and a protruding piece 5a1 is formed on the upper part of the vertical piece 5a, and a guide protrusion 5a is formed on the front surface of the base 5.
2 is formed, and a square hole 5a3 into which the pipe holder 2 is inserted is bored below.

On the other hand, the horizontal piece 5bvC communicates with the square hole 5a.
b, and two pole piece guide grooves 5b2 are formed in communication with the groove 5b1.

Further, a recess 5b3 is formed on the rear side surface of the horizontal piece 5b, in which a claw 6c of a shield plate 6, which will be described later, is engaged.
An engaging convex portion 5c1 that is engaged with b is formed.

Furthermore, the above-mentioned pole piece guide groove 5 is provided on the lower surface of the horizontal portion 5b.
An adhesive injection groove 5b4 communicating with b2 is bored.

The first pole piece T is made of a magnetically conductive material, and its magnetic detection end 7a is connected to the vertical piece 5 on the base 5vC.
It is aK molded and a part of the square hole 5a2vC is exposed.

Note that a part of the magnetic detection end 7a is cut out 7a, and the resin constituting the base 5 gets into this part during molding, so that the pole heath 7 does not come out.

Moreover, the length of the first pole piece 7 is formed to be approximately the same length as the horizontal piece 5b.

The shield plate 6 is made of a highly conductive non-magnetic metal such as copper, and has peaks 6a formed in its longitudinal direction.

A square hole is formed by this mountain portion 6a and a groove 5b1 formed in the horizontal portion 5b of the base 5, and the pipe holder 2 is inserted into the square hole.

Note that a protrusion 6a that protrudes toward the square hole side is formed on the mountain portion 6a.

This is to elastically press against the pipe holder 2 when the pipe holder 2 is inserted, to firmly hold the pipe holder 2 and to improve the contact.

Further, the front end of the mountain portion 6a is extended and folded back to form a bent piece 6b, and the bent piece 6tl: has a small hole 6b□ into which the first pole piece 7 is inserted.

Further, downwardly bent claws 6c are formed on both rear sides of the shield plate 6, and these are engaged with the recesses 5b3 of the base 5.

The coil 8 is wound on a bobbin 8aK, and the bobbin 8a is formed in a size such that the first pole piece 7 and the second pole piece 9 described later are inserted therein.

The second pole piece 9 is made of a magnetically conductive material and has a U-shape.

One end 9a of each second pole piece 9 is inserted into the bobbin 8a, and the other end 9b is inserted into the pole piece guide groove 5b2 of the base 50.

Next, the structure of the pedestal 10 will be explained. It is composed of a receiving part 10a, a lid part 10b, and a thin connecting part 10c.

At the front end of the receiving part 10a, there is a projecting piece 5 of the vertical piece 5a of the base 5.
A horizontal portion 10a2.a is formed with a cutout portion 10a1 that is engaged with the coil 8, and is located above the coil 8. The horizontal part 10
A hanging portion 10a3 that hangs down on both rear sides of a2 and faces the rear end of the coil 8, and a separation piece 10a4 that hangs down from the hanging portion 10a3 to the rear center thereof are formed.

Further, four terminal pins 12 are implanted in the lid portion 10bK, and a single lead wire from the coil 8 is connected to the terminal pins 12.

Further, this lid portion 10b has an engagement recess 10 formed on the extension piece 5c of the base 5 and engaged with the engagement protrusion 5c1.
b□ is formed.

Note that when the lid portion 10b is bent from the connecting portion 10c, the rear of the terminal pin 12 is located behind the hanging portion 10a3, that is, on both sides of the separation piece 10b40.

The shield case 11 is made of a magnetically permeable material and is used to prevent magnetism from external objects.The shield case 11 is open at the rear, and the assembled components such as the pickup device and the pedestal 10 can be inserted through this opening 11a. vcfx is there.

The front plate 1lbK has a hole 11b1 into which a guide protrusion 5a2 formed on the protrusion 5a of the base 5 is inserted.
A square hole 11b2 that matches the square hole 5a3 of the base 50 is bored.

Next, a method for assembling each component of the above structure will be explained.

First, a small hole 6b1 made in the bent piece 6b of the shield plate 6 is formed in each of the first pole pieces 7 molded and fixed to the base 5.
At the same time, the claws 6C are engaged with the recesses 5b3VC of the base 5, and the shield plate 6 is placed on the horizontal piece 5b of the base 5.

Next, the bobbins 8a are inserted into each of the first pole pieces 7.

Next, a jig formed to the same size as the pipe holder 2 and whose surface has been treated to prevent the adhesion of adhesive etc. is inserted into the groove 5b1 and the peak 6a of the shield plate 6 through the square hole 5a3. Insert it into the square hole formed by.

In this state, while inserting the other 9b of the second pole piece 9 into the guide groove 5b2 of the base 50, the bobbin 8a
Insert inside.

At this time, the second hole piece 9 is inserted in a crosswise manner.

Next, when adhesive is injected from the adhesive injection groove 5b4 of the base 5, the adhesive flows into the guide groove 5b2.

Therefore, each other 9b of the second pole piece 9 has a guide groove 5b2.
Since it is adhesively fixed inside, the tip does not protrude beyond the guide groove 5b2.

As a result, even if the pipe holder 2 is inserted after the jig is removed, the second pole piece 9 will not be caught, and the magnetic detection end 7 of the first pole piece 7 will not be caught.
The distance between a and the magnetic detection end at the tip of the second pole piece 9 facing it can be determined accurately.

Next, after fitting the protruding piece 5a1 of the base 5 into the notch 10a1 of the pedestal 10 and positioning the horizontal part 10a2 on the coil 8,
The lead wire from the coil 8 is soldered to the terminal pin 12.

After that, in a state where the base 5 and the pedestal 10 are combined, they are fitted through the opening 11a of the shield case 11, and the protruding piece 5a
The guide protrusion 5a formed at 1' is inserted into the hole 11 of the front plate 11b.
Insert into b1.

This positions the base 5 with respect to the shield case 11, and connects the base 50 square hole 5a3 and the shield case 1.
The square hole 11b2 of No. 1 matches.

Further, since the claws 6c of the shield plate 6 come into contact with the shield case 11, the shield plate 6 is grounded by grounding the shield case 11.

Demonstrates shielding effect.

Then, fill the resin from the opening 11a (be careful not to enter the square hole), and then place the resin on the lid 1 of the pedestal 11.
1b at the connecting part 11c, and the engaging convex part 5 of the base 5
c 1 is engaged with the engagement recess 10b1 of the lid portion 10b to form a lid.

The pickup cartridge is now complete.

As described above, this idea fixes one end of the first pole piece to the base, and connects the second pole piece with the coil fitted to the first pole piece and the pole piece insertion groove formed on the base. By fitting between them, both pole pieces are fixed at accurate positions relative to the base, and therefore, the positions relative to the pipe holder insertion holes are accurate, allowing for good playback. is formed by a base and a shield plate, and this shield plate has protrusions that make elastic contact with the pipe holder, so the pipe holder can be firmly held and the contact is good, and the shield plate is Since it comes in contact with the case and is grounded, it not only provides a shielding effect, but also has the advantage of being extremely easy to assemble since there is a pole piece insertion groove for inserting the second pole piece.

[Brief explanation of drawings]

The figures show one embodiment of the pickup cartridge according to this invention, in which Figure 1 is an exploded perspective view, Figure 2 is a side view showing the relationship between the replacement needle and the shield case, and Figure 3 is an assembled version of Figure 1. The latter sectional view, FIG. 4 is a bottom view of the base, and FIG. 5 is a central longitudinal sectional view of the same. A... Replacement needle, 2... Pipe holder, 5... Base, 5b2... Pole piece insertion groove, 6... Shield Board, 7...
1st pole piece, 8... Coil 9...
...Second pole piece.

Claims (1)

[Claims for Utility Model Registration] In a pink-up cartridge having a magnetic circuit parallel to the insertion direction of a replacement needle into a pie-to-holder. Fixing one end of the first pole piece of the base having a pipe holder insertion hole, and forming a pole piece insertion groove parallel to the pipe holder insertion hole of the magnetic base. In addition, a shield plate having a groove formed on the base and a peak forming a pipe holder insertion part is placed on the base,
In addition, a protrusion is formed on this crest that protrudes inward and comes into elastic contact with the pipe holder to be inserted, and the shield plate is further provided with a claw that contacts the shield case for grounding. A pickup cartridge characterized in that the magnetic circuit is constructed by inserting a coil into the first pole piece and inserting a second pole piece into the coil and the pole piece insertion groove.