JP2007287526A - Contact device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contact device capable of bringing a movable contact into contact with fixed contacts with desired contact pressure. <P>SOLUTION: The contact device A has a contact block 1 comprising a sealed container 10, a pair of fixed contacts 11a, 11a arranged in the sealed container 10, a movable contact 12 arranged in the sealed container 10 to contact and separate from both fixed contacts 11a, 11a, a contact pressure applying means 2 energizing the movable contact 12 to the fixed contact 11a, 11a side to bring the movable contact 12 into contact with the fixed contacts with predetermined contact pressure, and a regulating means 3 regulating the movement of the movable contact 12 to the fixed contact 11a, 11a side to hold the movable contact 12 in a spaced state from the fixed contacts 11a, 11a; and a driving block 4 releasing the movement regulation of the movable contact 12 by the regulating means 3 to bring the movable contact 12 into contact with the fixed contacts 11a, 11a. The contact pressure applying means 2 comprises a first coil spring 20 and a second coil spring 21 energizing the movable contact 12 to the fixed contact 11a, 11a side. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a contact device used for a power load relay, an electromagnetic switch, or the like.

  2. Description of the Related Art Conventionally, a so-called sealed contact device in which a fixed contact and a movable contact (or movable contact) contacting and separating from the fixed contact are accommodated in a sealed container has been provided (for example, Patent Document 1).

Hereinafter, such a contact device will be described with reference to FIG. A contact device 100 shown in FIG. 4 is provided with a sealing container 111 made of an insulating material whose one surface is open and a fixed contact 112a disposed in the sealing container 111, and is hermetically joined to the other surface portion of the sealing container 111. A pair of fixed terminals 112, 112, a movable contact 113 arranged in the sealing container 111 so as to be in contact with and away from the fixed contacts 112a, 112a, and an opening 111a of the sealing container 111 having a hole 114a. A yoke plate 114 that is airtightly joined, a fixed iron core 115 that is fixed to the yoke plate 114 while being positioned in the hole 114a, and a restriction that restricts movement of the movable contactor 113 to the fixed contact 112a side at one end. A shaft 116 that has a portion 116 a and is movably inserted through an insertion hole 115 a provided in the fixed iron core 115, and is disposed so as to face the fixed iron core 115 and the other end of the shaft 116 is fixed. Then, the movable contact 113 is movable in the direction in which the movable contact 113 is moved toward and away from the fixed contact 112a, and the movable iron 117 is movably accommodated and hermetically joined to one surface side of the yoke plate 114. A plunger cap 118 made of a magnetic material and a coil that is a contact pressure spring that urges the movable contact 113 toward the fixed contact 112a to bring the movable contact 113 into contact with the fixed contact 112a with a predetermined contact pressure (contact pressure). A contact block 110 including a spring 119, a return spring 120 interposed between the fixed iron core 115 and the movable iron core 117 and biasing the movable iron core 117 in a direction away from the yoke plate 114, and current flows. The drive block 200 includes a coil 210 that attracts the movable iron core 117 of the contact block 110 to the fixed iron core 115 by being excited.
Japanese Patent Laying-Open No. 2003-197082 (FIG. 1)

  In the contact device 100 described above, when the movable contact 113 is in contact with the fixed contact 112a and the contact is turned on, the movable contact 113 is unexpectedly caused by external factors such as vibration and impact. The movable contact 113 is fixed to the fixed contact 112a by biasing the movable contact 113 to the fixed contact 112a side by using the coil spring 119 so that the contact is not turned off from the fixed contact 112a. The contact reliability is improved with a predetermined contact pressure, thereby improving the contact reliability.

  However, since the coil spring 119 is interposed between the movable contact 113 and the yoke plate 114, the length of the coil spring 119 (in other words, the effective number of turns) is limited. Therefore, the coil spring 119 having a spring constant greater than or equal to a predetermined value cannot be used. Accordingly, in the contact device 100 shown in FIG. 4, the contact pressure when the movable contactor 113 contacts the fixed contact 112a is a desired value. There were many cases that could not be set.

  In particular, when the current capacity of the contact device 100 is increased, the contact pressure cannot often be set to a desired value. This is because when the current capacity of the contact device 100 is increased, it is necessary to increase the contact area between the movable contact 113 and the fixed contact 112a in order to reduce the contact resistance. Here, in order to increase the contact area between the movable contactor 113 and the fixed contact 112a, it is necessary to elastically deform the contact portion, and this can be achieved by increasing the contact pressure.

  In order to obtain a desired contact pressure in order to increase the contact area in this way, it is necessary to use the coil spring 119 having a larger spring constant, but the coil spring 119 that can be used as described above. There is a limit to the length of. For this reason, there is a limit to the contact pressure that can be obtained, and the larger the current capacity of the contact device 100, the greater the heat generated by the contact resistance, resulting in a decrease in energization performance (in other words, energization time limitation). Was.

  As described above, in the conventional contact device, since the movable contact 113 is brought into contact with the fixed contact 112a by using one coil spring 119, a desired contact pressure cannot be obtained, thereby reducing the energization performance. There was a problem of inviting.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a contact device capable of bringing a movable contact into contact with a fixed contact with a desired contact pressure.

  In order to solve the above-mentioned problems, in the invention of the contact device according to claim 1, the sealing container made of an insulating material, the fixed contact disposed in the sealing container, and the sealed contact so as to be in contact with and away from the fixed contact. A movable contact disposed in the stop container, a contact pressure applying means for urging the movable contact toward the fixed contact, and bringing the movable contact into contact with the fixed contact with a predetermined contact pressure, and a fixed contact of the movable contact And a contact block including a restricting means for restricting movement to the side and holding the movable contact member in a state of being separated from the fixed contact, and releasing the movement restriction of the movable contact by the restricting means to fix the movable contact to the fixed contact. The contact pressure applying means comprises a plurality of coil springs that urge the movable contact toward the fixed contact.

  In the present invention, the magnitude of the contact pressure when the movable contact contacts the fixed contact can be set by the respective spring constants of the plurality of coil springs. Even when the length of the coil spring (the maximum value of the spring constant of the coil spring) is limited, the movable contact can be brought into contact with the fixed contact with a desired contact pressure.

  Below, one Embodiment of the contact apparatus of this invention is described with reference to FIGS. 1-3.

  The contact device A of the present embodiment is a so-called sealed contact device (also referred to as a silent contact device), which is a sealing container 10 made of an insulating material and a pair of fixed contacts 11a arranged in the sealing container 10. , 11a, the movable contact 12 disposed in the sealed container 10 so as to be in contact with and away from both the fixed contacts 11a, 11a, and the movable contact 12 are urged toward the fixed contacts 11a, 11a to move the movable contact Contact pressure applying means 2 for bringing the contact 12 into contact with the fixed contacts 11a and 11a with a predetermined contact pressure, and the movement of the movable contact 12 toward the fixed contacts 11a and 11a is restricted, and the movable contact 12 is fixed to the fixed contact 11a, A contact block 1 having a regulating means 3 that is held away from 11a, and a drive block 4 that releases the movement restriction of the movable contact 12 by the regulating means 3 and brings the movable contact 12 into contact with the fixed contacts 11a and 11a. And contact And a housing (not shown) for accommodating the block 1 and the driving block 4. In addition to these, the contact device A includes a capsule yoke (not shown) for extinguishing an arc generated between the fixed contacts 11a, 11a of the contact block 1 and the movable contact 12 in a short time. Is provided.

  As shown in FIG. 1, the contact block 1 has a sealing container 10 made of an insulating material having an opening 10 a on one surface (the lower surface in FIG. 1), and a fixed contact 11 a disposed in the sealing container 10. A pair of fixed terminals 11 and 11 hermetically joined to the other surface (upper surface in FIG. 1) of the sealing container 10 and a movable member disposed in the sealing container 10 so as to be in contact with and away from the fixed contacts 11a and 11a. The contact plate 12, the yoke plate 13 having a hole portion 13a in the central portion and disposed opposite to the opening 10a of the sealing vessel 10, and the yoke plate 13 and the sealing vessel 10 are connected to seal the yoke plate 13. The sealing member 14 for airtightly joining to the stop container 10, the contact pressure provision means 2, and the control means 3 are provided.

  In the contact block 1, as shown in FIG. 2, the restricting means 3 includes a shaft 30 having a restricting portion 30a for restricting the movement of the movable contact 12 toward the fixed contact 11a at one end (the upper end in FIG. 1), The shaft 30 has an insertion hole 31 a and a flange 31 b at one end (upper end in FIG. 1), and the fixed iron core 31 attached to the yoke plate 13 and the fixed iron core 31 are fixed to the yoke plate 13. The stopper cap 32 and the other end (lower end in FIG. 1) of the fixed iron core 31 are arranged opposite to each other and the other end (lower end in FIG. 1) of the shaft 30 is fixed, and the movable contact 12 is connected to the fixed contact 11a. A movable iron core (plunger) 33 movably disposed in the contacting / separating direction; a plunger cap 34 that houses the movable iron core 33 movably and is hermetically joined to the yoke plate 13; A return spring 35 interposed between the fixed iron core 31 and the movable iron core 33 for holding the movable iron core 33 in a state of being separated from the fixed iron core 31, a bottom 34b of the plunger cap 34, and the movable iron A first elastic member 36 interposed between the core 34, a second elastic member 37 provided on a surface of the movable iron core 33 facing the fixed iron core 31 (upper surface in FIG. 1), and the fixed iron core 31. A third elastic member 38 interposed between the flange portion 31b and the yoke plate 13 and a fourth elastic member 39 interposed between the flange portion 31b of the fixed iron core 31 and the stopper cap 32. It is configured.

  The contact pressure applying means 2 includes a first coil spring 20 and a second coil spring 21 that are interposed between the movable contact 12 and the stopper cap 32.

  Below, each member which comprises the contact block 1 is demonstrated in detail with reference to FIGS. 1-3.

  As shown in FIGS. 1 and 3, the sealing container 10 is formed in a box shape having an opening 10 a on one surface (lower surface in FIG. 1) from a material having heat resistance and insulation properties such as ceramic. Contact insertion holes 10 b and 10 b for inserting the fixed contacts 11 a and 11 a of the fixed terminals 11 and 11 into the sealing container 10 are provided on the surface (upper surface in FIG. 1).

  The fixed terminal 11 is formed using a conductive material such as a copper-based material, for example, and is a screw hole 11b for screwing a terminal portion (not shown) for connecting to an external electric circuit such as a printed board. Is provided, and a fixed contact 11a is provided at the bottom of the cylindrical portion 11c. Here, as the fixed contact 11a, a conductive metal material having high welding resistance, environmental resistance, and heat resistance is used.

  The movable contact 12 is formed in a flat plate shape from, for example, a conductive material such as a copper-based material. A shaft insertion hole 12a through which the shaft 30 is inserted is formed at a substantially central portion, and the movable contact 12 is a fixed contact. It penetrates in the direction which contacts / separates 11a. Further, as shown in FIG. 1, a circular spring holding hole 12 b into which one end of the second coil spring 21 is fitted is formed on the surface of the movable contact 12 that faces the yoke plate 13 (the lower surface in FIG. 1). It is recessed. In order to improve the contact continuity with the fixed contacts 11a and 11a, the movable contact 12 is provided with a movable contact that contacts and separates from the fixed contacts 11a and 11a on the surface facing the pair of fixed terminals 11 and 11, respectively. You may do it. As the movable contact, as in the case of the fixed contact 11a, a conductive metal material having high welding resistance, environmental resistance, and heat resistance is used.

  The yoke plate 13 is formed in a flat plate shape having a size that can at least close the opening 10a of the sealing container 10 with a magnetic metal material such as iron, and includes a fixed iron core 31, a movable iron core 33, and a later-described yoke portion. 5 forms a magnetic circuit. In the substantially central portion of the yoke plate 13, a hole portion 13a for a fixed iron core having an inner diameter approximately equal to the outer diameter of a main body portion 31c of the fixed iron core 31 to be described later is formed. A fitting protrusion 13b for attaching the yoke portion 5 is integrally provided on the edge.

  The sealing member 14 is, for example, a synthetic resin molded product, and is formed in a rectangular tube shape with both surfaces (upper and lower surfaces in FIG. 1) opened. The sealing member 14 has one surface side (upper surface side in FIG. 1) hermetically joined to the edge of the opening 10a of the sealing container 10 and the other surface side (lower surface side in FIG. 1) on the yoke plate 13. In this case, the yoke plate 13 is hermetically joined to the sealing container 10 so as to close the opening 10 a of the sealing container 10.

  The shaft 30 is formed using, for example, a nonmagnetic material or the like, and has a substantially round bar-shaped shaft portion 30b. One end portion of the shaft portion 30b is integrally provided with a regulating portion 30a formed in a disk shape having an outer diameter larger than the outer diameter of the shaft portion 30b. The restricting portion 30a abuts on the surface of the movable contact 12 facing the fixed contacts 11a and 11a (the upper surface in FIG. 1A), and restricts the movement of the movable contact 12 toward the fixed contact 11a. belongs to. On the other hand, a thread groove (not shown) is formed at the other end of the shaft portion 30b. The shaft portion 30b is formed sufficiently longer than the axial length of the fixed iron core 31, and the other end portion of the shaft portion 30b is fixed even when the movable contact 12 is in contact with the fixed contacts 11a and 11a. The iron core 31 is not inserted into the insertion hole 31a.

  The fixed iron core 31 is formed using, for example, a magnetic material such as iron, and is provided on the above-described columnar main body portion 31c and one end edge of the main body portion 31c, and has an outer diameter larger than the outer diameter of the main body portion 31c. An annular flange portion 31b having a diameter is integrally provided. The fixed iron core 31 is provided with an insertion hole 31a extending in the axial direction. The insertion hole 31a has an inner diameter on the other end side larger than an inner diameter on the one end side. The other end portion side having a large inner diameter in the insertion hole 31 a is used as a storage chamber for the return spring 35.

  The stopper cap 32 is formed of, for example, a magnetic material or a non-magnetic material, and has a cylinder having an inner diameter equal to or larger than the outer diameter of the flange 31b of the fixed iron core 31 and a height larger than the thickness of the flange 31b. A portion 32b, a disc portion 32c that closes one end opening of the cylindrical portion 32b, and a flange portion 32d provided at the edge of the other end opening of the cylindrical portion 32b are integrally provided, and at a substantially central portion of the disc portion 32c. Is provided with a communication hole 32 a that communicates with the insertion hole 31 a of the fixed iron core 31. Further, in the disk portion 32c, the surface facing the movable contact 12 has an outer diameter similar to the inner diameter of the first coil spring 20, and the other end portion of the first coil spring 20 (the lower end portion in FIG. 1). ) And an annular rib 32e that is fitted into the body. Further, on the surface of the disk portion 32c that faces the fourth elastic member 39, a protrusion 32f that comes into contact with the fourth elastic member 39 is integrally provided.

  The movable iron core (plunger) 33 is formed in a substantially cylindrical shape using a magnetic material such as iron. The movable iron core 33 is provided with a hole 33a into which the other end of the shaft 30 is inserted in the axial direction. A screw corresponding to the thread groove of the shaft 30 is formed on the inner peripheral surface of the hole 33a. A groove (not shown) is formed.

  The plunger cap 34 is formed using, for example, a magnetic material or a non-magnetic material, and has a cylindrical portion 34a having an inner diameter substantially the same as the outer diameter of the movable iron core 33, and one end opening of the cylindrical portion 34a (the lower end opening in FIG. 1). ) And an annular flange portion 34c protruding outward from the edge of the other end opening (the upper end opening in FIG. 1) of the cylindrical portion 34a. The dimension is set to such a size that a space for moving the movable iron core 33 can be secured. Further, the inner peripheral surface of the cylindrical portion 34a is used as a sliding surface on which the movable iron core 33 slides.

  The return spring 35 is for urging the movable iron core 33 in a direction away from the fixed iron core 31 against the urging force of the contact pressure applying means 2, and between the fixed iron core 31 and the movable iron core 33. Intervened in between. As such a return spring 35, for example, a coil spring or the like is used. The length of the return spring 35 is such that one end (the lower end in FIG. 1) can protrude from the fixed iron core 31 when housed in the other end of the insertion hole 31a of the fixed iron core 31. Is set to

  The first elastic member 36 reduces impact (vibration) and impact sound when the movable iron core 33 collides with the plunger cap 34 when the movable iron core 33 is moved to the bottom 34b side of the plunger cap 34 by the return spring 35. For example, an elastic material such as rubber is used to form a disk having an outer diameter similar to the inner diameter of the plunger cap 34. The second elastic member 37 is for reducing impact and impact sound when the movable iron core 33 is moved to the fixed iron core 31 side by the drive block 4 and the movable iron core 33 collides with the fixed iron core 31. For example, it is formed in a disk shape having an outer diameter larger than the inner diameter on the other end side of the insertion hole 31a of the fixed iron core 31 using an elastic material such as rubber. A shaft insertion hole 37 a through which the shaft portion 30 b of the shaft 30 is inserted is formed at a substantially central portion of the second elastic member 37.

  The third elastic member 38 is used as a cushioning material for reducing an impact transmitted to the yoke plate 13 through the fixed iron core 31 when the movable iron core 33 collides with the fixed iron core 31. For example, an elastic material such as rubber is used to form an annular shape having an inner diameter comparable to the outer diameter of the main body 31c of the fixed iron core 31. The fourth elastic member 39 is used as a buffer material for reducing an impact transmitted to the stopper cap 32 through the fixed iron core 31 when the movable iron core 33 collides with the fixed iron core 31. For example, an elastic material such as rubber is used to form a disk having the same outer diameter as the flange 31b of the fixed iron core 31. Further, a shaft insertion hole 39 a through which the shaft portion 30 b of the shaft 30 is inserted is formed at the center of the fourth elastic member 39. By providing such third and fourth elastic members 38 and 39, when the movable iron core 33 collides with the fixed iron core 31, it is transmitted to the yoke plate 13 and the stopper cap 32 via the fixed iron core 31. The impact is reduced, thereby reducing the impact sound and preventing problems such as the stopper cap 32 being detached from the yoke plate 13 due to the aforementioned impact.

  The first coil spring 20 and the second coil spring 21 apply a contact pressure that urges the movable contact 12 toward the fixed contacts 11a and 11a and causes the movable contact 12 to contact the fixed contacts 11a and 11a with a predetermined contact pressure. The means 2 is configured, and the inner diameter of the second coil spring 21 is set larger than the outer diameter of the first coil spring 20. The coil springs 20 and 21 are interposed between the movable contact 12 and the disk portion 32c of the stopper cap 32 in a state where the center axes of the coil springs 20 and 21 coincide with the center axis of the shaft 30, respectively. Thus, the urging force by the coil springs 20 and 21 is applied to the movable contact 12 evenly.

  As described above, the contact pressure applying means 2 includes the first coil spring 20 and the second coil spring 21. Therefore, the contact pressure when the movable contact 12 contacts the fixed contacts 11a and 11a is as follows. The value is determined by the value of the spring constant of each of the coil springs 20 and 21. That is, according to the contact pressure applying means 2, the contact pressure can be set to a desired value by the spring constants of the two coil springs 20 and 21. Therefore, the degree of freedom in setting the contact pressure is improved as compared to the case where the contact pressure of the movable contactor 113 is set using one coil spring 119 as in the contact device 100 shown in FIG. In particular, even when the length of the coil spring is limited due to the space of the coil spring, the contact pressure applying means 2 is configured using the two coil springs 20 and 21 as in the present embodiment. Thus, a desired contact pressure can be obtained and contact reliability can be ensured.

  The contact block 1 is constituted by the members described above, and each member is attached as follows.

  A pair of fixed terminals 11 are provided on the sealing container 10 with an airtight sealing material such as wax on the other surface portion of the sealing container 10 in a state where the cylindrical portion 11c is inserted into the sealing container 10 from each contact insertion hole 10b. Airtight joined.

  On the other hand, on the yoke plate 13, the flange portion 30 b is made to face the surface (upper surface in FIG. 1) facing the movable contact 12 in the yoke plate 13, and the other end is moved from the hole 13 a to the movable contact 12 on the yoke plate 13. The fixed iron core 31 is attached in a state of projecting toward the surface (the lower surface in FIG. 1) that does not face the surface. At this time, the third elastic member 38 is interposed between the flange portion 31 b of the fixed iron core 31 and the yoke plate 13. In the yoke plate 13 to which the fixed iron core 31 is thus attached, the stopper cap 32 communicates the communication hole 32a with the insertion hole 31a of the fixed iron core 31 and covers one end of the fixed iron core 31. Thus, the yoke plate 13 is hermetically joined, and thereby the fixed iron core 31 is fixed to the yoke plate 13. At this time, the fourth elastic member 39 is interposed between the flange portion 31 b of the fixed iron core 31 and the stopper cap 32.

  Thereafter, the shaft portion 30b of the shaft 30 is arranged in the order of the shaft insertion hole 12a of the movable contact 12, the communication hole 32a of the stopper cap 32, the shaft insertion hole 39a of the fourth elastic member 39, and the insertion hole 31a of the fixed iron core 31. Insert. At the same time, one end portion of the first coil spring 20 is inserted into the holding hole 12b of the movable contact 12, and the rib 32e of the stopper cap 32 is fitted into the other end portion, whereby the first coil spring 20 is moved to the movable contact. 12 and the stopper cap 32, one end of the second coil spring 21 is fitted into the holding hole 12b of the movable contact 12, and the other end is brought into contact with the disk portion 32c of the stopper cap 32. Thus, the second coil spring 21 is interposed between the movable contact 12 and the stopper cap 32. As a result, the coil springs 20 and 21 are interposed between the movable contact 12 and the disk portion 32c of the stopper cap 32 in a state where the central axes coincide with each other, and the first coil spring 20 is attached to the stopper cap 32. Since the second coil spring 21 is fixed to the movable contact 12, the coil springs 20 and 21 are prevented from falling off.

  A return spring 35 is accommodated in the storage chamber in the insertion hole 31 a of the fixed iron core 31, and the other end portion of the shaft portion 30 b of the shaft 30 inserted through the insertion hole 31 a of the fixed iron core 31 is the movable iron core 33. Is inserted and fixed in the hole 33a. At this time, the second elastic member 37 is provided on the surface of the movable iron core 33 that faces the fixed iron core 30. A plunger cap 34 is attached to the yoke plate 13 by airtightly joining the flange portion 34c to the yoke plate 13 by laser welding or the like in a state where the fixed iron core 31 and the movable iron core 33 are housed inside. A first elastic member 36 is interposed between the bottom 34 b of the plunger cap 34 and the movable iron core 34.

  As described above, the movable contact 12, the first and second coil springs 20 and 21, the shaft 30, the fixed iron core 31, the stopper cap 32, the movable iron core 33, the plunger cap 34, the return spring 35, and the first The yoke plate 13 to which the fourth elastic members 36 to 39 are attached is attached to the sealed container 10 using the sealing member 14. In this attachment, one end side of the sealing member 14 is hermetically joined to the edge of the opening 10 a of the sealing container 10 by using a hermetic sealing material such as wax, and the other end side is connected to the sealing container 10 at the yoke plate 13. Is performed by airtight bonding using a hermetic sealing material such as wax, and at this time, an arc generated between the fixed contacts 11a and 11a and the movable contact 12 is generated in the sealing container 10 for a short time. Gas is sealed to turn off. In addition, as such a gas, a mixed gas mainly composed of hydrogen gas having the highest thermal conductivity in a temperature range where an arc is generated is used.

  The sealing block 1 configured as described above is stored in a state where the movable iron core 33 is in contact with the first elastic member 36 provided on the bottom 34b of the plunger cap 34 in the initial state. Further, although the movable contact 12 tries to move toward the fixed contacts 11a and 11a by the urging force of the contact pressure applying means 2, the movement toward the fixed contacts 11a and 11a is restricted by the restricting portion 30a of the shaft 30. For this reason, it is in a state of being separated from the fixed contacts 11a, 11a, that is, in a contact-off state. Therefore, the contact device A of this embodiment is a normally open type (normally off) sealed contact device.

  Next, the drive block 4 will be described. As shown in FIG. 1, the drive block 4 includes the yoke portion 5 and the electromagnetic drive portion 6 described above, and excites the movable iron core 33 by flowing current through the coil 60 of the electromagnetic drive portion 6 to excite it. The fixed iron core 31 is sucked, and thereby the restriction of the movable contact 12 by the restriction means 3 is released.

  The yoke part 5 constitutes a magnetic circuit together with the yoke plate 13, the fixed iron core 31, and the movable iron core 33, and includes a yoke 50 and a bush 51 as shown in FIG. The yoke 50 is formed in a substantially U shape from a magnetic metal material such as iron. More specifically, the yoke 50 is integrally provided with side plates 50a, 50a arranged in parallel with each other and a connecting plate 50b for connecting the base end portions of the side plates 50a, 50a. At the front ends of the side plates 50a, 50a, fitting recesses 50c, 50c are formed, which are engaged with the fitting projections 13b of the yoke plate 13, respectively. Further, an insertion hole 50d through which the bush 51 is inserted is formed at a substantially central portion of the connecting plate 50b. The bush 51 is for increasing the magnetic efficiency between the yoke 50 and the movable iron core 33. Like the yoke 50, the bush 51 is formed in a cylindrical shape using a magnetic metal material such as iron, and the outer diameter of the plunger cap 34. And a cylindrical portion 51a having an outer diameter comparable to the inner diameter of the insertion hole 50d, and a flange portion 51b projecting outward from one end of the cylindrical portion 51a.

  As shown in FIG. 1, the electromagnetic drive unit 6 includes a coil 60 and a coil bobbin 61 around which the coil 60 is wound, and the size of the electromagnetic drive unit 6 is the both side plates 50 a of the yoke portion 5. , 50a and the connecting plate 50b are set to a size that fits in the space. The coil bobbin 61 is formed using an insulating material, and has a substantially cylindrical winding drum portion 61a around which the coil 60 is wound, and substantially disc-shaped hooks formed at both axial ends of the winding drum portion 61a. It is provided integrally with the parts 61b and 61b. Here, as shown in FIG. 3, a binding portion 61c for binding the end portion of the coil 60 is integrally provided on one of the flange portions 61b (the flange portion on the lower end side in FIG. 1). Yes. The coil bobbin 61 is provided with a hole 61d having a circular cross section through which the plunger cap 34 is inserted in the axial direction. The hole 61d has an inner diameter that is equal to the outer diameter of the cylindrical portion 51a of the bush 51. The size is set to be approximately the same, so that the bush 51 can be inserted between the plunger cap 34 and the plunger cap 34.

  The drive block 4 composed of the yoke part 5 and the electromagnetic drive part 6 described above is attached to the sealing block 1 as follows. That is, the electromagnetic drive unit 6 is attached to the sealing block 1 with the plunger cap 34 inserted into the hole 61 d of the coil bobbin 61. The yoke 50 of the yoke portion 5 has the fitting recesses 50c, 50c of the side plates 50a, 50a and the fitting protrusions 13b of the yoke plate 13 with the plunger cap 34 inserted through the insertion hole 50d of the connecting plate 50b. , 13b are respectively attached to the contact block 1 by engaging the concave and convex portions, and the bush 51 inserts the cylindrical portion 51a into the gap between the plunger cap 34 and the inner peripheral surface of the hole 61d of the coil bobbin 61, and the flange portion. It is attached to the contact block 1 in a state where 51b is in contact with the connecting plate 50b.

  As a result, as shown in FIG. 3, the drive block 4 is attached to the sealing block 1, and these are housed in a housing (not shown), whereby the contact device A of the present embodiment is completed. In FIG. 3, the coil 60 is not shown.

  Next, operation | movement of the contact apparatus A of this embodiment is demonstrated. The contact device A of this embodiment is a normally open type as described above, and in the initial state, the movable contact 12 that is biased toward the fixed contacts 11a and 11a by the contact pressure applying means 2 is moved. The movable contact 12 is in a state of being separated from the fixed contacts 11 a and 11 a by being restricted by the restriction portion 30 a of the shaft 30.

  When the coil 60 of the drive block 4 is energized by exciting the movable iron core 33, the movable iron core 33 is attracted to the fixed iron core 31, and the movable iron core 33 is moved together with the shaft 30 against the biasing force of the return spring 35. 13 moves in the direction approaching 13 (the upward direction in FIG. 1). Along with this, the movement restriction of the movable contact 12 to the fixed contacts 11a, 11a side by the restriction portion 30a of the shaft 30 is released, and eventually the movable contact 12 is moved by the urging force of the contact pressure applying means 2. The contacts are moved to the positions where they come into contact with the fixed contacts 11a and 11a, respectively, and the contacts are turned on. In this state, the movable contact 12 comes into contact with the fixed contacts 11 a and 11 a by the contact pressure applied by the contact pressure applying means 2.

  On the other hand, when the excitation of the coil 60 of the drive block 4 is cut off, the movable iron core 33 is not attracted to the fixed iron core 31 side and is separated from the yoke portion 13 by the urging force of the return spring 35 (FIG. 1). Move downward). Along with this, the restricting portion 30a of the shaft 30 moves the movable contact 12 in a direction against the urging force of the contact pressure applying means 2, pulls the movable contact 12 away from the fixed contacts 11a, 11a, and returns to the initial state. To do.

  Here, when the movable contact 12 is separated from the fixed contacts 11a and 11a, an arc is generated as described above. This arc is cooled by the gas sealed in the sealing container 10. It will be promptly shut off. That is, in the contact device A of the present embodiment, an arc countermeasure is taken by cooling with the gas sealed in the sealing container 10.

  According to the contact device A of the present embodiment described above, the contact pressure applying means 2 for bringing the movable contact 12 into contact with the fixed contacts 11a and 11a with a predetermined contact pressure includes the two coil springs 20 and 21. The magnitude of the contact pressure when the movable contact 12 comes into contact with the fixed contact 11a can be set by the respective spring constants of the two coil springs 20 and 21, whereby, for example, the arrangement of the contact pressure applying means 2 is arranged. Even when the length of the coil springs 20 and 21 (the maximum value of the spring constant of the coil spring) is limited due to space limitations, the movable contact 12 can be brought into contact with the fixed contact 11a with a desired contact pressure. There is an effect.

  As described above, in the contact device A of the present embodiment, the movable contact 12 can be brought into contact with the fixed contact 11a with a desired contact pressure. Therefore, the current capacity is increased and the movable contact 12 and the fixed contact 11a are contacted. A desired contact area can be obtained, and it is possible to prevent the energization performance from deteriorating, and it is possible to design a contact device having a large current capacity (that is, a large-capacity contact device).

  In the contact device A of the present embodiment, the contact pressure applying means 2 is configured by using the two coil springs 20 and 21, but of course, it may be configured by three coil springs. Many coil springs may be used.

It is a schematic sectional drawing of the principal part of the contact apparatus of one Embodiment of this invention. It is a disassembled perspective view of the principal part of a contact device same as the above. It is a perspective view of the principal part of a contact device same as the above. It is a schematic sectional drawing of the principal part of the conventional contact apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Contact block 10 Sealing container 11a Fixed contact 12 Movable contact 2 Contact pressure provision means 20 1st coil spring 21 2nd coil spring 3 Control means 4 Drive block A Contact device

Claims (1)

  A sealing container made of an insulating material, a fixed contact disposed in the sealing container, a movable contact disposed in the sealing container so as to be in contact with and away from the fixed contact, and the movable contact on the fixed contact side And a contact pressure applying means for bringing the movable contact into contact with the fixed contact with a predetermined contact pressure, and the movement of the movable contact to the fixed contact side is restricted, and the movable contact is separated from the fixed contact. And a drive block for releasing the movement restriction of the movable contact by the restriction means and bringing the movable contact into contact with the fixed contact. A contact device comprising a plurality of coil springs biased toward the fixed contact side.

Images