JPH0535590Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention relates to a plug with a built-in noise filter that prevents noise superimposed on a power line from entering equipment, etc., and particularly aims to reduce the size and reliability of the plug body. This invention relates to a plug with a built-in noise filter that is designed to improve noise.

[Conventional technology]

Generally, in electrical equipment, etc., malfunction due to noise generated in power input/output lines is a problem, so a noise filter for removing noise is provided inside the equipment to prevent malfunction of equipment due to noise. However, while the power cord runs from the power outlet to the device, noise is generated superimposed on the commercial power supply, and the power cord often acts as an antenna and is affected by radiation. In order to prevent noise from entering such devices, various types of plugs with a built-in noise filter element are known, in which an Inozu filter element is incorporated inside the plug.

As a conventional plug with a built-in noise filter, for example, there is one shown in Utility Model Publication No. 63-20065. Fig. 6 shows a perspective view of this plug with a built-in noise filter, and Fig. 7 shows an exploded perspective view of the plug. .

In FIG. 6, the plug body 1 is molded from plastic such as vinyl chloride resin.
The plug body 1 has recesses 2 on the top and bottom, protrusions 3 on the left and right sides, and a cord protection part 4 on the rear end, and a pair of plug terminals 5 protrudes from the front end of the plug body 1. At the same time, an earth pin receiver 8 is provided which is integrated with the earth plate 7 exposed from the recess 2. Plug body 1 via cord protection part 4
As will be described later, the cord 10 introduced into the plug body 1 has two cord cores and one grounding core, and the two cord cores and the pair of plug terminals 5 are connected to the plug body 1.
The grounding wire core is connected to the grounding plate 7 through a noise filter element (described later) disposed therein.

Next, the internal structure of the plug body 1 will be explained based on FIG. The insulating base 13 formed by molding plastic or the like has a connecting end 6.
A pair of plug terminals 5 having the same diameter and a grounding plate 7 having a connecting terminal 9 on the back thereof are fixed, and insertion holes 14 into which the engaging legs 34 of the split cover 16a are inserted are formed on both sides of the insulating base 13. It is formed. Between the connection end 6 of the plug terminal 5 and the cord core 12 of the cord 10, a chiyoke coil consisting of two insulated wire cores 19 wound around an annular core 18 is connected as a noise filter element 17.
One of the lead ends 20 of the plug terminal 9 is connected to the cord core 12 of the cord 10 via the connection terminal 21, and the other lead end 20 is connected to the connection end 6 of the plug terminal 5. Further, the ground wire core 11 of the cord 10 is connected to the connection terminal 9 of the ground plate 7. The noise filter element 17 is fitted into the element arrangement portions 30 of a pair of split covers 16a and 16b constituting the cover 16, and is housed inside by fitting them together with their palms together. At this time, the connection terminals 21 are simultaneously inserted into the terminal insertion grooves 37 of the split cover 16a,
It is held between the two by fitting.

In the above configuration, when the plug terminal 5 connected to the device via the cord 10 is plugged into a power outlet, the device is grounded via the grounding wire core 11 and the grounding plate 7, and the plug terminal 5 and the cord are connected to each other. The noise filter element 17 connected in series with the wire core 12 can prevent line noise from entering the equipment side via the power outlet and the cord 10.

[The problem that the idea attempts to solve]

However, the conventional noise filter built-in plug has the following problems.

(1) The chiyoke coil at the rear of the insulating base has the same arrangement structure as when the chiyoke coil is built into a so-called domestic general plug that has a flat blade-shaped plug terminal, that is, the axis of the annular core and the axis of the cord are the same. Because they are arranged orthogonally, if this arrangement is applied to relatively thick plugs such as those for Europe, the larger the chiyoke coil is, the longer the plug body will be.
The plug becomes larger.

(2) The connection terminal that connects the lead end of the chiyoke coil and the cord core is inserted into the groove of one split cover and held between the other split covers, so the connection is made by the molding pressure when molding the plug body. The terminal will fall out of the groove.

(3) Since the pair of split covers are engaged by a concave-convex engagement, the engagement may be disengaged due to the molding pressure during molding of the plug body.

(4) Since the Chi-Yoke coil housed in the cover is fixed by contacting the Chi-Yoke coil with the peripheral wall of the element placement area, if a gap is created between the peripheral wall and the Chi-Yoke coil, the Chi-Yoke coil may move within the element placement area. This movement may cause damage to the annular core and the lead ends of the windings wound around it.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an insertion plug with a built-in noise filter that can reduce the size of the plug, particularly in the length direction, and solve the problem of concentration of tension associated with this.

Another object of the present invention is to provide an insertion plug with a built-in noise filter that is unaffected by the molding pressure during molding of the plug body and has high reliability.

Still another object of the present invention is to provide a plug with a built-in noise filter that can prevent damage to the annular core and lead ends by eliminating movement of the choke coil.

[Means for Solving the Problem] In order to achieve the above-mentioned object, the present invention provides the noise filter configured by winding a pair of windings connecting the cord and the pair of plug terminals around an annular core. A chiyoke coil as an element, an insulating cover for accommodating the chiyoke coil, and a plug body integrally molded from the bases of the pair of plug terminals to the cord, and the insulating cover includes a cover body forming a substantially cylindrical body; and a cover lid body, which is engaged with the rear end of the insulating base via engaging legs protruding from the outer bottom of the cover body, and the cover body has an inner hole of the annular core at its inner bottom. a fixing protrusion that is inserted into the cover lid is integrally provided with a connection terminal that connects the cord and the lead end of the winding; To provide an insertion plug with a built-in noise filter, which is housed in the insulating cover so as to be in the same direction as the axis of the cord.

The insulating cover also provides a noise filter built-in plug that is locked by a locking window provided on the cover lid and a locking protrusion on the cover body.

[Effect]

In the above configuration, the chiyoke coil is arranged behind the insulating base so that the axis of the annular core and the axis of the cord are in the same direction, so the length taken by the chiyoke coil in the plug length direction is equal to the thickness of the chiyoke coil, and the insulation The length from the rear part of the base to the end of the cord, ie, the length of the plug body, can be shortened, and as a result, the plug can be made smaller. Moreover, the movement of the chiyoke coil housed within the insulating cover is regulated within the cover, in which a fixing protrusion protruding from the cover body is fitted into the inner hole of the annular core. The fitting of the insulating cover is
Since this is achieved by the locking between the locking protrusions formed on the cover body and the cover lid and the locking window, the fitting force is considerably greater than that of a concave-convex engagement. Furthermore, since the connection terminal is provided integrally with the cover lid, it will not come off from the cover lid. Due to this increased mechanical strength,
It is no longer affected by molding pressure, etc.

〔Example〕

Hereinafter, the noise filter built-in plug of the present invention will be explained in detail.

FIG. 1 is a partially cutaway plan view showing an embodiment of the present invention, in which a pair of plug terminals 102 are mounted on an insulating base 110, and a ground pin holder (not shown) is provided on the distal end surface of the insulating base 110. A ground plate 103 integrated with the insulating base 110 is fixed.
A chiyoke coil as a noise filter element 130 is housed inside the insulating cover 120 engaged with the rear end in such a manner that the axis of the annular core and the axis of the cord 105, which will be described later, are in the same direction. One lead end (described later) of a noise filter element 130 led out from the insulating cover 120 is connected to the connecting end 104 of the plug terminal 102, and the other lead end of the noise filter element 130 is connected to the insulating cover 120 integrally. Connection terminal 1 provided in
34. A cord core of a cord 105 to be described later is connected to this connection terminal 134, and an electrical connection is made between the cord core and the plug terminal 102, and a grounding core of the cord 105 to be described later is connected to the ground plate 103. . A plug body 100 integrally formed of plastic such as vinyl chloride resin is provided from the base of the plug terminal 102 to the cord 105.
has a supporter 101 at its rear end that relieves the tension and bending applied to the cord 105.

FIG. 2 is an exploded perspective view showing the internal structure of the plug body 100. The insulating base 110, which is formed by integrally molding plastic or the like, is comprised of a substantially rectangular parallelepiped base body 109 and a substantially rectangular base body 109 located on both sides of the tip thereof. It has a semicircular fixing part 108, a pair of plug terminals 102 are fixed to the fixing part 108 so that the connecting end 104 is exposed, and a ground pin holder ( (not shown) and is formed into a substantially U-shape.
3 is fixed by protruding pieces 112 protruding from both sides of the base body 109 and an earth pin receiving fitting inserted into the insulating base 110. A substantially semicircular insertion hole 113 is formed in the center of both sides of the base body 109 from the rear end to the tip, and the engagement leg of the cover body 120B, which constitutes a part of the insulating cover 120, is inserted into the insertion hole 113. 121 is inserted. The insulating cover 120 is a cover body 120B
and a cover lid body 120A, and an annular core 13 is installed therein as a noise filter element 130.
1 houses a chiyoke coil having a pair of windings 132 wound thereon. One lead end 133 of the winding 132 of this noise filter element 130 is led out from a lead-out hole 135 formed in the circular upper part 137 of the cover lid 120A, and is integrally provided on the cover lid 120A. The other lead end 133 of the winding 132 is connected to a connecting terminal 134 protruding from the circular bottom 1 of the cover body 120B.
It is led out from a lead-out hole 126 formed in 27 and connected to the connection end 104 of the plug terminal 102 fixed to the insulating base 110. Cover body 120B
There are two engaging legs 121 on the outside of the circular bottom 127 of the
The engagement leg 121 is formed in a tapered shape so that the distance between the engagement legs 121 becomes smaller toward the tip. That is, the insertion hole 113 of the insulating base 110
When the engagement leg 121 is inserted, the tip of the engagement leg 121 expands, so elastic force is generated in the engagement leg 121.
The insulating base 110 is pressed by this elastic force, and as a result, the insulating base 110 and the cover body 1
20B is engaged. A fixing protrusion 122 is provided protruding inside the circular bottom portion 127, and the inner hole 130A of the noise filter element 130 is inserted into the fixing protrusion 122, thereby fixing the noise filter element 130. In the circular upper part 137 of the cover lid body 120A,
The end of the cord 105 is formed with a cord holding part 136, in which two cord cores 106 and one grounding wire core 107 are twisted together, and a jacket is applied to the outer periphery of the cord holding part 136. The cord core 106 exposed from the end of the cord 105 is pulled out from the gap formed at the opposite position of the cord holding part 136 to form a connection terminal to which the lead end 133 of the noise filter element 130 is connected. 134 and also the code 105
The grounding wire core 107 exposed from the terminal of the cord holding part 136 is pulled out from another gap of the cord holding part 136, and is further removed from the cover lid body 120A and the cover body 120.
It is connected to the connection terminal 111 of the ground plate 103 via fixing grooves 125 formed in the peripheral wall portions 129 and 123 of B, respectively. The cover lid body 120A and the cover body 120B are connected by a locking window 128 formed in the peripheral wall portion 129 of the cover lid body 120A and a locking protrusion 124 formed in the peripheral wall portion 123 of the cover body 120B. Can be fitted.

3a, b, c, and d show the cover lid body 120A, which consists of a circular upper part 137 and a peripheral wall part 129 surrounding the circular upper part 137. The circular upper part 137 has a cord wire outlet 136a and a ground wire outlet. Business drawer outlet 13
6b, the lead end 133 of the noise filter element 130, and the cord core 1.
A connecting terminal 134 for making the connection 06 is integrally provided, and a lead-out hole 135 for leading out the lead end 133 is further formed in the inner part of the connecting terminal 134. A locking window 128 that engages with the locking protrusion 124 of the cover body 120A is formed at a position facing the peripheral wall portion 129, and a locking window 128 that engages with the locking protrusion 124 of the cover body 120A is formed in the peripheral wall portion 129. A fixing groove 125 for accommodating the wire core 107 is formed.

FIGS. 4a, b, c, and d show the cover body 120B, which consists of a circular bottom part 127 and a peripheral wall part 123 surrounding the circular bottom part 127. On the outside of the circular bottom part 127, the distance between the two becomes smaller toward the tip. The two engaging legs 121 are tapered so that the base 1
21a, and is provided inside the circular bottom portion 127 with a fixing protrusion 122 that is inserted into the inner hole 130A of the annular core 131. Peripheral wall portion 123
A fixing groove 125 and a locking protrusion 124 are formed so as to align with a fixing groove 125 and a locking window 128 formed in the peripheral wall portion 129 of the cover lid body 120A, respectively.

Such a cover lid body 120A and a cover body 1
20B accommodates the noise filter element 130 as an insulating cover 120 by integrating the noise filter element 130 as shown in FIGS. 5a and 5b. That is, in the noise filter element 130 placed on the circular bottom part 127 of the cover body 120B, the fixing protrusion 122 protruding from the circular bottom part 127 is inserted into the inner hole 130A of the annular core 131, so that the movement of the noise filter element 130 is prevented. It is regulated and the cover body 120B
The locking protrusion 124 and the locking window 128 of the cover lid body 120A are locked, and the cover lid body 120A and the cover body 120B are fitted. Insulating cover 12 in which noise filter element 130 is housed in this way
0 to the rear portion of the insulating base 110, the noise filter element 130
is arranged so that the axis of the inner hole 130A and the axis of the cord 105 are in the same direction. The mechanical strength of the plug body 100 needs to be increased by the amount that the length of the entire plug is shortened by arranging the York coil so that the axis of the annular core 131 is parallel to the direction of the coat 105. Although the mechanical strength is increased by fixing the connection terminal 134 to the cover body 120A with a mold,
0B or the mechanical strength of the cover lid body 120A itself may be increased. Preferably, the cover lid body 120A has the connecting terminal 134 fixed thereto.
The thickness of the cover body 120B is approximately twice that of the cover body 120B. By doing so, it is possible to improve the mechanical strength against concentration of insertion/extraction force, etc., while keeping the shape small.

In the above configuration, the noise filter element 13
0 is fitted into the fixed protrusion 122 of the cover main body 120B, one lead end 133 of the pair of windings 132 is led out from the lead-out hole 126 to below the circular bottom part 127, and further, the annular core 13
The circular bottom part 127 of the cover main body 120B
The noise filter element 130 is placed inside the cover body 120B so as to be in contact with the cover body 120B. Then, the fixing grooves 125 of the cover lid body 120A and the fixing grooves 125 of the cover body 120B are fitted together with their palms together so that they are integrated. That is, the other lead end 133 of the pair of windings 132 is led out from the lead-out hole 135 formed in the circular upper part of the cover lid 120A, and the cover main body is inserted into the locking window 128 formed in the peripheral wall 129 of the cover lid 120A. The locking protrusion 124 formed on the peripheral wall 123 of 120B is engaged. Next, the cover body 120 is inserted into the insertion hole 113 of the insulating base 110.
Insert the engaging legs 121 of B and attach the insulating base 110.
An insulating case 120 housing a noise filter element 130 is connected to the rear of the cover body 1.
Lead end 13 led out from lead-out hole 126 of 20B
3 to the connecting end 104 of the plug terminal 102. Thereafter, the cord 105 which has been peeled off by a predetermined dimension and the cord core 106 and the grounding wire 107 are exposed from the terminal is brought into contact with the cord holding part 136, and the wire cores 106, 107 are held in the cord holding part 136.
The cord core 106 is pulled out from the cord wire outlet 136a and the ground wire outlet 136b, respectively, and the cord core 106 is connected to the connection terminal 13 together with the lead end 133 led out from the outlet hole 135 of the cover lid body 120A.
4, and the ground wire core 107 is connected to the insulation cover 1.
The insulating base 11 is fixed to the fixing groove 125 of 20.
Connection terminal 111 of ground plate 103 fixed at 0
Connect to. Thereafter, a plug body 100 having a supporter 101 is provided by integrally molding plastic resin from the base of the plug terminal 102 to the end of the cord 105.

According to the noise filter built-in plug of this embodiment, the following effects can be achieved.

(1) The noise filter element 130 connected to the plug terminal 102 and the cord core 106 is arranged so that the axis of the annular core 131 and the axis of the cord 105 are in the same direction. The length of up to
The plug body 100 can be downsized.

(2) The connection terminal 134 for connecting the lead end 133 of the noise filter element 130 to the cord core 106 is fixed to the cover lid 120A by integral molding, so that the fixing strength is increased and the plug body 1
When molding the cover lid 100, the connection terminal 134
This will prevent the cable from coming off 20A or from being damaged.

(3) Cover lid body 120A and cover body 120B
are integrated by locking the locking protrusion 124 into the locking window 128, so that the cover lid body 120A and the cover body 120B will not come off when the plug body 100 is molded.

(4) The noise filter element 130 housed in the insulating cover 120 is inserted into the inner hole 1 of the annular core 131.
30A is the fixing protrusion 122 of the cover body 120B.
Since the noise filter element 130 is inserted and fitted, the noise filter element 130 does not move within the insulating cover 120.

[Effect of idea]

As explained above, the plug with a built-in noise filter of the present invention can provide the following effects.

(1) Because the chiyoke coil is placed behind the insulating base so that the axis of the annular core and the axis of the power cord are in the same direction, the length of the chiyoke coil was previously at least as long as the outer diameter of the annular core. On the other hand, the length of the plug body can be shortened by only needing the thickness of the annular core, and therefore the plug can be made smaller.
Additionally, as a secondary effect, the amount of materials (plastic resin, etc.) used can be reduced, leading to cost reductions.

(2) There is no movement of the chiyoke coil within the insulating cover, which prevents damage to the annular core, winding lead ends, etc., and improves the reliability of the plug. As a result, productivity can be improved.

(3) Since the mechanical strength of the insulating cover and the connection terminals provided thereon has been increased, it will no longer be damaged by the molding pressure during molding.
For this reason, we have improved the reliability of the plug,
Productivity can be improved.

(4) Since the inner bottom of the cover body is provided with a fixing protrusion that fits into the inner hole of the annular core, damage to the annular core and the connecting portion of the winding can be prevented. Therefore, productivity and reliability of the plug can be improved.

(5) Since the cover lid body and the cover body are locked by the locking window of the cover lid body and the locking protrusion of the cover body, the cover body and the cover lid body will not be separated.

(6) Since the engaging legs are provided that protrude from the outer bottom of the cover body, strong engagement is possible using elastic force.

(7) As the length of the plug body becomes shorter, the load per unit length such as insertion/extraction force increases, causing damage to the choke coil, the connection between the cord and the winding, and the connection between the plug terminal and the winding. However, this can be prevented by combining the above configurations.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway plan view showing an embodiment of the present invention, Fig. 2 is an exploded perspective view showing the internal structure before molding, and Figs. 3 a, b, c, and d show the cover body. Explanatory drawings, Fig. 4 a, b, c, and d are explanatory drawings showing the cover body, Fig. 5 is a sectional view showing a state in which a noise filter element is accommodated in the insulating cover, and Fig. 6 is a conventional plug-in with a built-in noise filter. FIG. 7 is an explanatory view showing the plug, and FIG. 7 is an exploded perspective view showing the internal structure of FIG. Explanation of symbols, 1... Plug body, 2... Recessed part,
3... Protrusion, 4... Cord protection part, 5... Plug terminal, 6... Connection end, 7... Earth plate, 8... Earth pin holder, 9... Connection terminal, 10... Cord, 11... ...Earth wire core, 12...Cord wire core, 13...Insulation base, 14...Insertion hole, 16
...Cover, 16a, 16b...Divided cover, 1
7... Noise filter element, 18... Annular core,
19...Insulated wire core, 20...Lead end, 21...
Connection terminal, 30...Element placement part, 34...Engaging leg, 37...Terminal insertion groove, 100...Plug body, 101...Supporter, 102...Plug terminal, 103...Earth plate, 104...Connection edge, 1
05...cord, 106...cord wire core, 107
...Earth wire core, 108...Fixing part, 109...
... Base body, 110 ... Insulation base, 111 ...
... Connection terminal, 112 ... Projection piece, 113 ... Insertion hole, 120 ... Insulation cover, 120A ... Cover lid body, 120B ... Cover body, 121 ... Engagement leg, 121a ... Base, 122 ... Fixation protrusion, 1
23... Peripheral wall portion, 124... Locking protrusion, 125...
...Fixing groove, 126... Lead-out hole, 127... Circular bottom, 128... Locking window, 129... Peripheral wall, 13
0...Noise filter element, 130A...Inner hole,
131... Annular core, 132... Winding wire, 133...
...Lead end, 134... Connection terminal, 135... Outlet hole, 136... Cord holding part, 136a... Cord wire outlet, 136b... Ground wire outlet, 137... Circular top.

Claims (1)

[Claims for Utility Model Registration] (1) An insulating base having a pair of plug terminals fixed to its tip portion to be connected to a cord via a noise filter element, and a pair of plug terminals to connect the cord and the pair of plug terminals. A chiyoke coil as the noise filter element configured by winding a winding around an annular core, an insulating cover that accommodates the chiyoke coil, and a plug body integrally molded from the base of the pair of plug terminals to the cord. , the insulating cover is composed of a cover main body and a cover lid body forming a substantially cylindrical body, and is engaged with the rear end of the insulating base via engagement legs protruding from the outer bottom of the cover main body, The cover body is provided with a fixing protrusion that is inserted into the inner hole of the annular core at its inner bottom, and the cover lid body is integrally provided with a connection terminal that connects the cord and the lead end of the winding. A plug with a built-in noise filter, wherein the chiyoke coil is housed within the insulating cover so that the central axis of the annular core is in the same direction as the axis of the cord. (2) The noise filter built-in plug according to claim 1, wherein the insulating cover is locked by a locking window provided on the cover lid and a locking protrusion on the cover body.