JPH11162309A - Reed switch and reed relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reed switch and a reed relay, which are shield by a non-magnetic electric conductor and which are excellent from the standpoints of miniaturization, an inexpensive price, convenience or the like. SOLUTION: A lead switch is formed by coating a hermetic container 13 with a shield 14. A flange 23, in which a reed piece 12 and a terminal 14a of the shield 14 are insert molded, is provided, by using the reed switch. A reed relay is formed by winding an exciting coil around the outer circumference of the shield 14, having the flange 23 as the both ends. Besides, as another example, the assembling process of the reed relay may be simplified by integrating the shield, the reed switch and the flange by the flange insert-molded with the terminal of the shield and the reed piece.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reed switch and a reed relay shielded by a non-magnetic conductor,
Particularly, the shield and the reed switch are integrally formed.

[0002]

2. Description of the Related Art Reed relays shielded by nonmagnetic conductors are intended for so-called coaxial relays.
6-122243, JP-A-58-10342, etc .; and a so-called electrostatic shielded relay for the purpose of reducing capacitance, contact noise, etc. between lead contacts (JP-A-5-1982).
7-76730, JP-A-59-86128).
Although there is no description in the conventional example as a reed relay having both of these purposes, there is a case where it is assumed that both purposes can be substantially achieved by the configuration of the shield or the like. Below,
A conventional example will be described from the viewpoint of a shielded reed relay.

FIG. 6 shows a conventional example of a reed relay shielded by a nonmagnetic conductor. FIG. 6A) shown in a sectional view corresponds to a prototype of a shielded reed relay, and FIG. 6C shows a sectional view of a conventional example in which this is improved (JP-A-57-76730).

In FIG. 6A), a shield 2 is provided in a hollow portion of a bobbin 4 around which an exciting coil 5 is wound, and a reed switch 1 is disposed at the center of the shield 2. As the shield 2, a copper tube 2a shown in 1) of FIG. 6B) or a copper foil 2b shown in 2) is used. The lead terminals 3 are connected to the shields 2 by welding or soldering.

The reed relay shown in FIG. 6C) has been devised because the connection of the terminal 3 is complicated. The shield is composed of the coil 7, and the end 8 of the coil 7 is used as a terminal, thereby avoiding the work of welding and soldering. FIG.
C) 1) is an example in which the coil 7 is wound around the bobbin 4, and 2) is an example in which the bobbin 4 is omitted using a self-fusing polyurethane copper wire. The excitation coil 5 is wound on a shielding coil 7.

Further, there is disclosed an example of a shield (not shown) in which connection of the terminal 3 is not required and the terminal portion and the cylindrical portion are integrally formed of copper foil. This example inserts this shield into the hollow part of the bobbin around which the exciting coil is wound, then inserts the reed switch into the cylindrical shield, connects each terminal to the electrode on the mounting plate, and assembles the reed relay It is. However, during this assembly process,
Because the shield is easily deformed and requires careful attention to the work, and there is a problem such as contact between the terminal of the shield and the lead piece, the shield is formed by a coil similar to 1) of FIG. 6C). (Japanese Patent Laid-Open No. 7-78541).

[0007]

The method of using a coil as a shield has a rational configuration in which the coil of the shield and the exciting coil are integrally laminated. However, different functions are required for each coil. It is difficult to design the optimally. Further, in the case of a coaxial reed relay, for example, the shield coil is wound over a considerable length of the one reed terminal, so that the bobbin of the coil also becomes large and the whole reed relay becomes large.
There is also a problem that the price of the shield itself is higher than that of a thin plate or foil shield.

In the case of a foil-shaped shield, as described in the related art, it is difficult to assemble a reed relay using a conventional method, such as insertion of a reed switch. Furthermore, in conventional shields made of thin plates or foils, the fixing that determines the positional relationship between the reed switch, the shield, and the bobbin of the exciting coil is not integrally performed, so that many man-hours are required for position adjustment, assembly, and fixing. There's a problem.

As described above, the conventional shielded reed relay cannot simultaneously satisfy design redundancy, simplicity of assembly, small size, low cost, and the like.

[0010]

SUMMARY OF THE INVENTION One aspect of the present invention is a reed switch in which a shield is attached around a sealed container made of glass or the like in which a contact portion of a reed piece is sealed. Correspondingly, the shield is integrated with a normal reed switch.

When the shield is attached to the sealed container, copper, aluminum, or the like is vapor-deposited, sputtered, or the like, or a conductive paste or solution is applied, sprayed, dipped, etc., and then dried. A method of forming a non-magnetic conductor film on the substrate or a method of fixing a non-magnetic conductor such as a copper foil wound around a sealed container with an adhesive or the like is used. Further, the surface of these non-magnetic conductors may be coated with an insulating resin, so that the reed switch of the present invention is easier to handle and helps to stabilize the shield characteristics.

The terminal of the shield is conveniently fixed integrally with the lead piece via an insulator. Since the protruding portion of the lead piece has high mechanical strength, the terminal of the shield is firmly fixed. In such a form, the convenience of connection with the electric circuit is also improved.

One of the reed relays of the present invention uses a reed switch in which the shield is attached to a sealed container. The length and position of the exciting coil provided on the outer periphery of the shield are defined by resin-molded flanges provided at both ends thereof. When this flange is formed, a portion of the reed piece projecting from the sealed container is insert-molded to integrate the flange with the reed switch.
Since the positional relationship between the flange and the reed switch is determined by loading the reed switch into the molding die, high positional accuracy can be easily secured. Since the flange and the reed switch are fixed and the shield is fixed to the reed switch by such a simple method, the reed relay can be easily assembled.

Also, if the terminal portion of the shield is also insert-molded on the flange, the terminal of the shield is firmly fixed. Also in this case, the terminals of the shield and the lead pieces protruding from the sealed container may be arranged in consideration of the convenience of connection with the circuit.

Another reed relay of the present invention can be applied to a reed switch in which the shield is not attached to the sealed container, and the shield and the reed switch are integrally fixed by a flange.

A shield made of a non-magnetic conductor is provided on the outer periphery of the sealed container enclosing the contact portion of the lead piece, and a resin-molded flange is provided on both ends of the exciting coil wound around the outer periphery of the shield. The flange is formed by insert molding a part near the end of the shield and a part of the lead piece protruding from the sealed container.

In the insert molding, the shield and the reed switch are arranged in accordance with the molding die, so that the positional relationship between the shield, the reed switch and the flange is determined uniquely and is fixed integrally. The position of the exciting coil is also determined by the flange. As described above, these positional accuracy can be easily secured and fixed at once, so that the assembling process of the reed relay is simplified.

When the above-described shield is applied to a so-called coaxial reed relay, it is desirable to provide the shield around the outer periphery of the reed switch, including the portion of the reed piece protruding from the sealed container.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a view for explaining the basics of a reed switch according to the present invention. FIG. 1A) is a sectional view of an embodiment in which a shield is attached to a sealed container, and FIG. Shows a plan view of an example in which the terminals of the shield are taken out.

In FIG. 1A) 1), a shield 14 is attached around a sealed container 13 enclosing the contact portion of the lead piece 12. The shield 14 only needs to be a non-magnetic conductor, and various methods such as the following can be applied as a method of attachment. A film may be formed by applying a film forming method using a vacuum technique or a medium in which a resin, a metal powder, or the like is mixed, and drying the film, or may be formed by a known spray, dipping, or the like. In addition, an adhesive is applied to the surface of the sealed container 13, and a metal foil or the like is wound thereon, a metal foil or the like to which the adhesive is applied is wound around the sealed container 13, or a metal foil or the like is sealed in the sealed container. There is also a method of fixing with an adhesive after winding around the cable 13.

Regarding an example of the terminal 14a of the shield 14,
This will be described with reference to FIG. 1B). In 1), the tip of a copper wire or the like is crushed as shown by a dotted line, and the flattened terminal 14a is first fixed to the sealed container 13 with an adhesive, and then the shield 14 is attached. In the case where the shield 14 is formed of a film, a conductive paste or the like is applied around the bonding portion of the terminal 14a to smooth the steps, thereby increasing the reliability of the electrical connection between the shield 14 and the terminal 14a. When a metal foil or the like is used for the shield 14, if a conductive paste or the like is applied to the upper surface of the bonding portion of the terminal 14a, the connection between the shield 14 and the terminal 14a is highly reliable.

FIG. 1B) 2) shows an example in which a metal foil or the like is used for the shield 14, in which the terminal 14a is cut out continuously with the shield 14 by a metal foil or the like. In 3), a terminal 1 made of a metal foil or the like having an expanded surface indicated by a dotted line
4a is an example. In this case, an adhesive is applied to the entire surface of the sealed container 13 on which the shield 14 is attached, and the terminal 14a and the shield 14 are sequentially laminated. Terminal 1
By utilizing the widened surface of the terminal 4a, the terminal 14
a, the terminal 14a can be fixed even if the periphery of the shield 14 is fixed with an adhesive after the shield 14 is sequentially laminated.

FIG. 1A) 2) shows an example of a reed switch in which the shield 14 and one of the reed pieces 12 are connected depending on the use of the reed switch. Shield 1 in this case
For 4, it is convenient to use a film formed by vacuum evaporation or application of a medium mixed with resin, metal powder, or the like. Shield 14
In order to increase the reliability of the connection between the lead piece 12 and the
It is also effective to apply a conductive paste or the like to the base of the hermetically sealed container 13.

Referring to FIG. 2, an example of a specific method for attaching the shield 14 to the sealed container 13 using the technique of vacuum deposition will be described. 1A to 4) of FIG. 2A) are schematic sectional views showing the outline of the process. 1) shows a state before attachment, and 2) shows a state in which a portion on the left side of the sealed container 13 and the lead piece 12 in the figure is covered with a peelable layer 31 such as a resist layer. An example of a method of coating the peelable layer 31 is shown in FIG. 2B), and the end of the sealed container 13 is immersed in the mother liquid 32 of the peelable layer, pulled up, and dried.

FIG. 2A) 3) shows a state in which the shield 14 is applied by vacuum evaporation following 2). One example of this vacuum deposition method is shown in FIG. 2C). The portions of the left and right lead pieces 12 protruding from the sealed container 13 are sandwiched between two sets of slide plates 33a and 33b. Slide plate 33a
And 33b are slid in the directions of arrows A and B in opposite directions, and the sealed container 13 is rotated in the direction of arrow R following the lead piece 12. Heating and evaporating a base material 35 such as copper or aluminum from an evaporation boat 34, and rotating the sealed container 1
3 is deposited on the surface. The base material 35 may be heated by a known method such as electron beam or resistance heating, and it goes without saying that this deposition is performed in a vacuum vessel (not shown).

FIG. 2A) 4) shows a state in which the peelable layer 31 is removed after the vapor deposition of 3), and the shield 14 is attached only to a predetermined portion of the sealed container 13. Peelable layer 31
The removal may be performed by a known technique such as immersion in a stripping solution.

FIG. 2D) shows another method of applying a shield by vacuum deposition to only a predetermined portion of the sealed container 13 without using the peelable layer 31 described above. Shielding plates 36a, 36
An example is shown in which b is used to form a shield film only at the center without being attached to both ends of the sealed container 13 where the vapor of the base material 35 rotates. If only one shield plate is used, it goes without saying that a shield 14 equivalent to 4) in FIG. 2A) is attached.

In order to apply a medium in which resin, metal powder and the like are mixed, or to immerse the medium without using the vacuum technology, and to apply the shield film to the sealed container 13, the following method is used. Applicable (illustration omitted). It is needless to say that a well-known surface treatment method such as cleaning and surface activation treatment of the surface of the sealed container 13 can be applied as needed before application.

The method of applying to the sealed container 13 is a method of applying a medium (for example, silver paste) to a predetermined portion of the sealed container 13 using a brush and a blade while rotating the sealed container 13, A technique such as a method in which a medium is dropped on the top, the sealed container 13 is pressed and rotated from above, and the medium is applied around the outer diameter of the sealed container 13 is used. These methods can also be applied to the application of an adhesive for attaching another copper foil or the like to the sealed container 13.

The immersion method is basically the same as that shown in FIG.
Similarly to D), the sealed container 13 is immersed in the medium up to the portion where the film is to be formed. The coating applied to one of the lead pieces 12 can be removed with a solvent or the like.

FIG. 3 is a partial sectional view of an example of a reed switch in which the reed piece 12 and the terminal 14a of the shield are integrally fixed by an insulator. FIG. 3A) shows an example in which a resin 15 is mounted on an end of a sealed container 13 and a lead piece 12 and a terminal 14a of a shield 14 are integrally fixed.
Further, in this example, the entire surface of the shield 14 is covered with the resin 15. The resin 15 on the shield 14 has the effects of insulating the surface of the reed switch of the present invention, protecting the shield 14, and the like.

FIG. 3B) shows an example in which the lead piece 12 and the terminal 14a are integrally fixed by an inner ring 16 and an outer ring 17 formed by resin molding or the like. Inner ring 1
6 is provided with a hole through which the lead piece 12 penetrates, and a groove for fitting the terminal 14a is provided outside the ring.
The outer ring 17 fits the inner ring 16. A connection line 18 is insert molded into the outer ring 17 and is exposed to allow contact with the terminal 14a inside the ring. The assembly may be performed as shown in the drawing, but the lead piece 12, the inner ring 16, and the outer ring 17 may be bonded to each other. Lead piece 1
2. It is also possible to connect the connection line 18 to an electric circuit using a connector.

FIG. 3C) is an example adapted by a coaxial reed switch. It is convenient for the shield 14 to use a thick metal foil (thin plate) or the like. An adhesive is applied to the periphery of the sealed container 13, and a metal foil or the like is wound thereon to form a shield 14. The shield 14 and the lead piece 12 are fixed by the resin 19. For example, a cover is placed on the left end of the shield 14, resin flows into the hole 27, and is cured to obtain the resin 19. In the figure, the center conductor 21, the insulator 20, the outer conductor 2
2 shows an example in which the coaxial line constituted by 2 is connected to a reed switch.

FIG. 4 is a sectional view showing an example in which a reed relay is constructed by using a reed switch in which a shield 14 is attached to a sealed container 13. 4A), the lead piece 12 and the terminal 14a are insert-molded on the resin-molded flange 23 on the left side of the figure, and the lead piece 12 on the right side of the figure. An exciting coil 24 is wound around the shield 14 between the two flanges 23. Since the positions of the lead piece 12 and the terminal 14a are determined according to the molding die and the flange 23 is integrally formed, it is easy to secure the positional accuracy of each of them and fixed at a time. Thereafter, if the exciting coil 24 is wound in accordance with the flange 23, the reed relay is completed, and the assembly is simplified.

In the example of FIG. 4B), a reed switch in which the shield 14 is connected to one reed 12 is used. In this example, when forming the flange 23, the periphery of the reed switch between the left and right flanges 23 is also resin-molded, and the terminal mounting portion 25 is further insert-molded. Therefore, the exciting coil 24 is wound around the reed switch via the resin. Also, the exciting coil 24
Can be fixed to the terminal mounting portion 25.

In FIG. 4C), the sealed container 1 of the lead piece 12 is shown.
3 also extends over a long area to shield 14
An example of a reed relay surrounded by is shown. In this case, it is convenient to use a thick metal foil or the like as the shield 14, or to wind a plurality of metal foil layers. An adhesive is applied around the sealed container 13, and a metal foil or the like is wound and fixed. In this example, a material such as silicone rubber is injected into the cylinder of the shield 14 protruding from the sealed container 13 and cured,
The example in which the buffer 26 was provided was shown. The buffer 26 is not particularly required only in this example, and is provided as necessary in view of conditions such as the mechanical strength of the lead piece sealing portion and the pressure of resin molding.

Next, a flange 23 of a resin molded body is formed by insert-molding the projecting portion of the lead piece 12, the end of the shield 14, and the terminal 14a. An exciting coil 24 having both ends of the flange 23 is wound on the shield 14.

The reed piece 12 and the terminal 14a are integrally fixed by the shield 14, and the position of the exciting coil 24 with respect to the reed switch is uniquely determined, so that the assembly of the reed relay is rationalized as described above.

FIG. 5 shows that the shield 14 is not previously attached to the sealed container 13 and the vicinity of the end of the shield 14 is
An example of a reed relay integrated by a flange 23 formed by insert molding is shown. In this example, the shield 14
A thick metal foil, a thin metal plate, or the like was used.

FIG. 5A) shows a cross-sectional view of an example adapted by a coaxial reed relay. A reed switch and a shield 14 composed of a reed piece 12 and a sealed container 13 are
It is loaded according to a molding die (not shown). Shield 1
The four cylinder walls have holes 27 for resin inflow (there is also a hole (not shown) for resin outflow), and a resin stopper (not shown) that penetrates the lead piece 12 is inserted into the end of the shield 14 cylinder. Place in position.

In the resin molding of the flange 23, the resin is
, And also flows into the cylinder of the shield 14, and the part of the lead piece 12 is also integrally formed. Resin-molded flange 23
An exciting coil 24 is wound around the outer periphery of the shield 14 between the two. It goes without saying that the insulating property may be improved by using a known technique such as providing an insulating film between the shield 14 and the exciting coil 24.

FIG. 5B) is a partial view showing an example in which a reed relay is assembled using a lead frame in which a shield and a plurality of terminals are connected. FIG. 5B) is a perspective view partially showing the lead frame 30. In the lead frame 30, the terminal 14a connected to the shield 14 and the terminal mounting portions 28 and 29 are continuous. The stamped flat plate is bent into a cylindrical shape in the shield 14 and bent at the terminal 14a and the terminal mounting portions 28 and 29 with a step as shown in the drawing.

The lead frame 30 processed into this shape
Then, a reed switch including the sealed container 13 and the reed piece 12 is loaded at a predetermined position of the molding die. Using this molding die, the flange 23 is resin-molded, and predetermined portions of the lead piece 12, the shield 14, the terminal 14a, and the terminal mounting portions 28 and 29 are also resin-molded integrally. After molding, the portion of the lead frame 30 indicated by the two-dot broken line aa is cut.

FIG. 5B) 2) is a partial sectional view of the reed relay of this embodiment, and 3) is a side view. The flange 23 is L-shaped, and its base 23a has terminals 14 on it.
a, the step portions of the terminal mounting portions 28 and 29 are insert-molded, and the respective terminal portions are exposed on the upper and lower surfaces of the base 23a.

An exciting coil 24 is provided between two flanges 23.
Wrap. The connection portion 28a of the terminal attachment portion 28 is bent and connected to the lead piece 12 by soldering or the like. Although the connection part 29a of the terminal mounting part 29 is also shown in a state of being bent vertically, a coil tip (not shown) of the excitation coil 24 can be connected. The reed relay is mounted on an electric circuit such as a printed board, and each terminal is connected to the circuit at a lower portion of the base 23a.

In the reed relay shown in FIG. 5, the portion near the end of the shield 14 and the portion of the reed piece 12 protruding from the sealed container 13 are integrally fixed to the flange 23. And the reed relay is very easily assembled.

[0047]

According to the first aspect of the present invention, there is provided a reed switch in which a shield is integrated. The handling of the reed switch as a single unit is simple, and the cost of the shield can be reduced.

[0048] In addition to the above effects, the second aspect facilitates connection with an electric circuit. A third aspect of the present invention is a reed relay in which a reed piece is insert-molded on a flange. The reed switch is easily adjusted in position and fixed collectively, so that assembly is simplified.

According to the fourth aspect, in addition to the above effects, the connection with the electric circuit is simplified and stabilized. The reed relay in which the reed piece and the shield end are insert-molded in the flange is easy to adjust the position of the reed switch and the shield and is integrally fixed, so that the assembly is simplified.

Claim 6 provides a coaxial reed relay,
More compatible.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining the basics of a reed switch of the present invention.

FIG. 2 illustrates a method for forming a shield by vacuum evaporation.

FIG. 3 is a cross-sectional view of an end of a reed switch, showing an embodiment of fixing a lead piece and a shield terminal.

FIG. 4 is a sectional view showing an embodiment of a reed relay using a reed switch in which a shield is attached to a sealed container.

FIG. 5 is a diagram showing another embodiment of a reed relay.

FIG. 6 is a diagram for explaining a conventional example.

[Explanation of symbols]

Reference Signs List 1 reed switch 2 shield 2a copper tube 2b copper foil 3 terminal 4 bobbin 5 exciting coil 6 end of exciting coil 7 coil 8 end 11 reed switch 12 lead piece 13 sealed container 14 shield 14a terminal 15 resin 16 inner ring 17 outer ring DESCRIPTION OF SYMBOLS 18 Connection wire 19 Resin 20 Insulator 21 Center conductor 22 External conductor 23 Flange 24 Excitation coil 24a Winding tip 25 Terminal mounting part 26 Buffer 27 Hole 28 Terminal mounting part 28a connection part 29 Terminal mounting part 29a connection part 30 Lead frame 31 Peelable layer 32 Mother liquid of peelable layer 33 Slide plate 34 Evaporation boat 35 Base material 36 Shield plate

Claims (6)

[Claims] 1. A lead comprising: a pair of lead pieces; a sealed container enclosing a contact portion of the lead piece; and a nonmagnetic conductor shield attached around the sealed container. switch. 2. A portion of the lead piece protruding from the sealed container and a terminal of the shield are integrally fixed via an insulator near an end of the sealed container. Item 7. A reed switch according to Item 1. 3. A pair of lead pieces, a sealed container enclosing a contact portion of the lead pieces, a nonmagnetic conductor shield attached around the sealed container, and provided on the outer periphery of the shield. A reed relay, comprising: an excitation coil; and resin-molded flanges at both ends of the excitation coil, wherein portions of the reed pieces protruding from the sealed container are insert-molded in the flange. . 4. The terminal portion of the shield is insert-molded on the flange.
Reed relay as described. 5. A pair of lead pieces, a sealed container enclosing a contact portion of the lead pieces, a nonmagnetic conductor shield provided on the outer periphery of the sealed container, and a shield provided on the outer periphery of the shield. An exciting coil, and resin-molded flanges at both ends of the exciting coil. A portion near the end of the shield and a portion of the lead piece protruding from the sealed container are insert-molded into the flange. Reed relay characterized by the following. 6. The reed relay according to claim 3, wherein the shield is provided on an outer periphery including a portion of the lead piece protruding from the sealed container.