JP4910900B2 - Contact device - Google Patents

Description

  The present invention relates to a contact device such as an electromagnetic contactor or an electromagnetic relay. In particular, the present invention relates to a contact device that can improve contact reliability without greatly changing the basic structure in an auxiliary contact device having a low minimum operating current.

The electromagnetic contactor controls the opening and closing of the electric circuit by switching the contact and separation between the fixed iron core and the movable iron core using the attractive force of the electromagnetic coil. First, the structure of a general electromagnetic contactor will be described.
FIG. 6 is a perspective view of a general electromagnetic contactor.
FIG. 7 is a perspective view showing the internal structure of the electromagnetic contactor of FIG.
As shown in FIG. 6, the magnetic contactor 1 has a lower frame 10 and an upper frame 20 that are divided into upper and lower cases, and inside these, as shown in FIG. 7, a fixed iron core 30 and a movable iron core. 40, an electromagnetic coil 50, a contact device 60 having a main contact device 70 and an auxiliary contact device 80, and the like.

  This will be described with reference to FIG. The fixed iron core 30 is an E-shaped iron core in which a plurality of plates are stacked and fixed with rivets, and is housed in the lower frame 10 in a floating state. A central leg of the iron core 30 is inserted into the electromagnetic coil 50. A through-hole penetrating in the thickness direction is formed in the fixed iron core 30, and a support plate 31 is inserted into the through-hole. Both ends of the support plate 31 protrude from the through hole, and an elastic body 32 made of an elastic member such as rubber is attached to the same end. The support plate 31 is fixed to the lower frame 10 by the elastic body 32, and the fixed iron core 30 is supported in a floating state with respect to the lower frame 10.

  The movable iron core 40 is a substantially E-shaped member disposed facing the fixed iron core 30 and is accommodated in the upper frame 20 so as to be in contact with and away from the fixed iron core 30. A return spring 41 is interposed between the movable iron core 40 and the electromagnetic coil 50.

  The contact device 60 includes a main contact device 70 and an auxiliary contact device 80. In this example, the main contact device 70 is arranged at three poles in the center of the main body, and the auxiliary contact device 80 is arranged at one pole on both sides of the main contact device 70. The main contact device 70 is used for a circuit having a relatively large amount of current used, and the auxiliary contact device 80 is used for a circuit of a signal system (several V, several mA) having a relatively small amount of current used. Each contact device 70, 80 has a movable contact 71, 81 and a fixed contact 72, 82, and is an electrical contact that switches between connection and disconnection of a circuit by abutting and separating from each other.

The main movable contact 71 and the auxiliary movable contact 81 are held by the movable contact support 42. The movable contact support 42 is supported by a connecting plate (not shown) on the back surface (upper surface) of the movable iron core 40 and is slidable in the upper frame 20. A window is formed in the movable contact support 42, and a main movable contact 71 and an auxiliary movable contact 81 are inserted into the window portion, and contact springs (not shown) are respectively contact springs (not shown). (Not shown).
On the other hand, the main fixed contact 72 and the auxiliary fixed contact 82 are fixed to a portion of the upper frame 20 facing the main movable contact 71 and the auxiliary movable contact 81. These contact devices 60 are covered with a contact cover 62 (see FIG. 6).

  When the electromagnetic coil 50 is excited, the fixed iron core 30 and the movable iron core 40 are attracted to each other, and the movable iron core 40 moves and is attracted to the fixed iron core 30. As a result, the movable contact support 42 supported by the movable iron core 40 moves with respect to the upper frame 20, so that the main and auxiliary movable contacts 71, 81 come into contact with the main and auxiliary fixed contacts 72, 82. When the excitation of the electromagnetic coil 50 is released, the movable iron core 40 is urged by the return spring 41 and moves away from the fixed iron core 30. As a result, the main and auxiliary movable contacts 71 and 81 are separated from the main and auxiliary fixed contacts 72 and 82.

Next, the structure of the auxiliary contact device 80 (auxiliary movable contact 81 and auxiliary fixed contact 82) of the electromagnetic contactor 1 will be described.
8A and 8B are perspective views showing the structure of the double contact type contact device, in which FIG. 8A shows a non-contact state, and FIG. 8B shows a contact state.
The auxiliary contact device 80 is mainly used for the operation circuit, and the applied electricity is a low voltage and small current (several V, several mA), so that the contact reliability of the contact is particularly required to be high. Is done.

The auxiliary contact device 80 includes one movable contact 81 and two fixed contacts 82 as shown in FIG. The movable contact 81 has a bridge shape, and includes a mounting portion 81a with which a central spring receiver abuts, and a contact base 81b supported in a plate spring manner from both ends of the mounting portion 81a. Each contact base 81b is divided into two by a cut groove 81c, and a movable contact 81d is provided on the back surface of the front end of each divided piece. This type is called a double contact type, and the probability of contact failure is lowered by increasing the number of contact points.
On the other hand, a fixed contact 82a is fixed to a portion of the fixed contact 82 facing the movable contact 81d of each contact base 81b of the movable contact 81. The fixed contact 82a is a flat or knurled flat plate that has an acute angle and is unlikely to cause poor contact.

  At the time of contact conduction, each movable contact 81 d of the movable contact 81 comes into contact with the fixed contact 82 a of the fixed contact 82 as shown in FIG.

  By the way, in general, an electromagnetic contactor has a structure in which there is no gap as much as possible so that foreign matter is less likely to enter the contact device. However, very fine dust such as wear powder and dust in the air generated when the electromagnetic contactor is opened and closed enters the contact device. Such dust adheres or accumulates on the contact surface of the contact of the contact device. With respect to such dust, the contact device acts as follows to obtain contact reliability. When the movable contact 81 comes into contact with the fixed contact 82, the contact base 81b of the movable contact 81 is elastically deformed in the longitudinal direction of the contact, and the movable contact 81d remains in contact with the fixed contact 82a. Slide slightly in the direction. By this movement, fine dust on the contact surface is scraped off, and the contact surface is always kept clean.

  In order to further improve the contact reliability, a proposal has been proposed in which the movable contact and the spring receiver are brought into contact with each other by a line or a point to improve the contact due to the deflection of the movable contact (see Patent Document 1). ).

In addition, the contact surface is oxidized to form a thin oxide film, which may cause poor contact. For this, a movable contact provided with a plurality of contact portions of the same height arranged across the center line has been proposed (see Patent Document 2). The contact portion can be formed in a shape such as a rib shape, a conical shape, or a spherical shape. Since such a contact portion is in sliding contact with the fixed contact, dust adhering to the contact portion and the formed oxide film are scraped off and cleaned.
Furthermore, there has also been proposed a method in which a plurality of protrusions with sharp tips are projected on the fixed contact and a plurality of protrusions with sharp tips are also projected on the movable contact (see Patent Document 3). In this example, the contact pressure is improved and the contact reliability is obtained by making the protrusion of the fixed contact and the protrusion of the movable contact substantially orthogonal.

JP-A-2-297817 Japanese Utility Model 58-131547 JP 58-12219 A

  As described above, the contact device can solve the problem of fine dust and oxide coating by deformation of the movable contact or sliding contact between the contacts as described above. However, the electromagnetic contactor has a structure with no gap as much as possible so that the foreign material does not easily enter the contact device. However, since it is not completely sealed, in rare cases, the fibrous foreign material enters the contact device. Sometimes.

FIG. 9 is a perspective view showing a state in which a fibrous foreign matter adheres to the fixed contact.
As shown in FIG. 9, when the fibrous foreign matter F adheres across the surface of the fixed contact 82 a, it cannot be scraped out by the above-described movement on the contact surface of the movable contact.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a contact device having improved contact reliability even with respect to fibrous foreign matter.

  A first contactor device according to the present invention includes a fixed contactor having a fixed contact, and a movable contactor having a plurality of movable contacts arranged to face and separate from the fixed contact. A partition formed of linear protrusions and planar contact portions on both sides of the partition are formed on the contact surface of the fixed contact, and each contact of the movable contact is the fixed contact It contacts each of the planar contact portions on both sides of the partition.

  According to the present invention, since the partition made of linear protrusions is provided on the contact surface of the fixed contact, it is possible to extremely reduce the possibility that the fibrous foreign matter adheres so as to straddle both contact portions. Contact reliability between the child and the stationary contact can be improved. In addition, the planar shape of the planar contact portion is meant to include a slightly uneven surface such as a knurled surface or an inclined surface.

  A second contact device of the present invention is a contact device comprising a fixed contact having a fixed contact, and a movable contact having a movable contact disposed so as to face and separate from the fixed contact. A partition made of linear protrusions and planar contact portions on both sides of the partition are formed on the contact surface of the fixed contact, and a groove for accommodating the partition on the contact surface of the movable contact Is formed.

  In the case of the single contact type, it is common that only the movable contact corresponds to the single contact type, and the fixed contact is the same as the double contact type. Since the contact of a single contact type movable contact is generally formed in a conical shape, when a fixed contact having a fixed contact with a protruding partition is used, the movable contact hits the linear protrusion and is fixed. The contact and the movable contact do not make regular contact, which may impair the original performance. Therefore, if a groove for accommodating the partition is formed at the contact of the movable contact, the partition fits into the groove when the movable contact and the stationary contact come into contact with each other. As a result, the portions on both sides of the groove of the movable contact easily come into contact with the contact portions on both sides of the partition of the fixed contact, so that contact reliability can be improved and original performance can be maintained while avoiding interference between the contacts.

  A contact reliability improving method for a first contactor device according to the present invention includes: a fixed contact having a fixed contact; and a movable contact having a plurality of movable contacts arranged to contact and separate from the fixed contact. A contact device of the contact device comprising: a partition composed of linear protrusions on the contact surface of the fixed contact; and planar contact portions on both sides of the partition; Each contact of the movable contact is brought into contact with the planar contact portion of the fixed contact, thereby reducing the possibility that a fibrous foreign matter simultaneously adheres to the planar contact portions on both sides of the partition and causes contact failure. It is characterized by that.

  According to the second contact device improvement method of the present invention, there is provided a fixed contact having a fixed contact, and a movable contact having a movable contact disposed so as to face and separate from the fixed contact. A contactor device comprising: a partition made of linear protrusions on the contact surface of the fixed contact; and planar contact portions on both sides of the partition; Forming a groove for accommodating the partition on a contact surface of the contact; and contacting portions on both sides of the groove on the contact surface of the movable contact with the planar contact portions on both sides of the partition of the fixed contact, respectively. Thus, it is possible to reduce the possibility that the fibrous foreign matter simultaneously adheres to the planar contact portions on both sides of the partition and causes contact failure.

  As is clear from the above description, according to the present invention, when a fibrous foreign matter enters the contact device, it is difficult to attach the foreign matter to the contact of the stationary contact. Thus, a contact device with improved contact reliability can be provided.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a perspective view showing a structure of a contact device (double contact type auxiliary contact device) according to the first embodiment of the present invention. FIG. 1 (A) is a non-contact state, and FIG. ) Indicates the contact state.
The auxiliary contact device 180 has the same configuration as the auxiliary contact device 80 shown in FIG. 8, and includes one movable contact 181 and two fixed contacts 182. The movable contact 181 has a bridge shape, and includes a central mounting portion 181a with which a spring receiver abuts, and a contact base 181b supported in a plate spring form from both ends of the mounting portion 181a. The contact base 181b is divided into two by a cut groove 181c, and a movable contact 181d is provided on the back surface of the tip of each divided piece.

  A fixed contact 182a is fixed to a portion of the fixed contact 182 where the movable contact 181d of the two contact bases 181b of the movable contact 181 faces each other. The fixed contact 182a is a flat plate on a flat surface or a knurled surface, and a partition 182b made of a linear protrusion extending in the length direction is formed at the center in the width direction. By this partition 182b, two contact portions 182a-1 and 182a-2 are formed on the fixed contact 182a. Each of the contact portions 182a-1 and 182a-2 is opposed to each of the movable contacts 181d of the movable contact 181. Since the partition 182b faces the cut groove 81c of the contact base 181b of the movable contact 181, it does not interfere with the movement of each divided piece of the contact base 181a and does not affect the contact performance.

  At the time of contact conduction, as shown in FIG. 1B, each of the movable contacts 181d of the movable contact 181 comes into contact with each fixed contact 182a-1 or 182a-2 of the fixed contact 182.

Consider a case where a fibrous foreign material adheres to such a contact device.
FIG. 2A is a perspective view showing a state in which fibrous foreign matter is attached to the stationary contact, and FIG. 2B is an enlarged view of a part of FIG.
As shown in FIG. 2B, when the fibrous foreign matter F adheres across the partition 182b to the contact portions 182a-1 and 182a-2, the foreign matter is contacted by the partition 182b with the contact portions 182a-1, It is difficult to stagnate at 182a-2. That is, the fibrous foreign matter F is inclined by the partition 182b, and one end is in contact with the one contact portion 182a-2, but the other end is in a state of floating from the other contact portion 182a-1, and is not in contact with the same portion. Moreover, even if it adheres to both contact part 182a-1 and 182a-2 on both sides of the partition 182b, possibility that it will adhere to the part which contacts the two contact 181d of the movable contact 181 simultaneously is low. In addition, when the fibrous foreign material F adheres only to one contact part 182a-1, the other contact part 182a-2 can be used without a problem.

  Therefore, even if a fibrous foreign matter enters the fixed contact 182, the contact 182 and the movable contact 181d are reliably in contact with each other.

FIG. 3 is a perspective view showing an internal structure of an electromagnetic contactor including the contact device of FIG.
This electromagnetic contactor has substantially the same structure as the electromagnetic contactor described with reference to FIG. 6, and uses the auxiliary contactor device 180 shown in FIG. 1 as the auxiliary contactor device of the contactor device 160.

FIG. 4 is a diagram showing a structure of a contact device (double contact type) according to the second embodiment of the present invention.
The contact device of this example has substantially the same structure as the contact device 180 of FIG. 1, but the length of the partition 282b provided on the fixed contact 282a of the fixed contact 282 is short. This is because it has a shape that takes into account the contact manufacturing process, and when press molding, it is easier to make a flat surface at both ends. Even if the linear protrusion (partition 282b) is slightly shortened in this way, the effect is not changed.

FIG. 5A is a perspective view showing a structure of a contact device (single contact type) according to a third embodiment of the present invention, and FIG. 5B shows a movable contact shown in FIG. It is the perspective view seen from the bottom.
The contact device 380 of this example also includes a movable contact 381 and a fixed contact 182 as in the contact device 180 of FIG. The fixed contact has the same configuration as that of the fixed contact 182 of FIG. 1, but the movable contact 381 is not divided into two parts, and the movable contact 381d is provided on the back of the tip of each contact base 381d. ing. This type is called a single contact type. Such a single contact type is used for an application having a larger current capacity than a double contact type. In such a case, it is general that only the movable contact corresponds to the single contact type, and that the fixed contact is the same as the double contact type. The contact 381d of the single contact type movable contact 381 is formed in a conical shape to break the oxide film.

  As described above, when the contact of the movable contact is conical, if the partition 182b is formed on the fixed contact 182a of the fixed contact 182 as in the above-described example, there is sufficient space between the fixed contact and the movable contact. The contact area cannot be obtained. Therefore, as shown in FIG. 5B, a groove 381e extending in the length direction is formed at the center in the width direction of each contact point 381d of the movable contact 381. When the movable contact 381 and the fixed contact 182 come into contact with each other, the partitions 182b of the respective contacts 182a of the fixed contact 182 are accommodated in the grooves 381e. As a result, the contacts 381d on both sides of the groove 381e of the movable contact 381 easily come into contact with the contact portions 182a-1 and 182a-2 on both sides of the partition 182b of the fixed contact 182a.

  As described above, even in the case of the single contact type, the partition 182b can be provided on the fixed contact 182a to make it difficult to attach fibrous foreign matters without affecting the contact performance.

It is a perspective view which shows the structure of the contactor apparatus (double contact type) which concerns on the 1st Embodiment of this invention, FIG. 1 (A) shows a non-contact state and FIG. 1 (B) shows a contact state. FIG. 2A is a perspective view showing a state in which fibrous foreign matter is attached to the stationary contact, and FIG. 2B is an enlarged view of a part of FIG. It is a perspective view which shows the internal structure of the electromagnetic contactor provided with the contactor apparatus of FIG. It is a figure which shows the structure of the contactor apparatus (double contact type) which concerns on the 2nd Embodiment of this invention. FIG. 5A is a perspective view showing a structure of a contact device (single contact type) according to a third embodiment of the present invention, and FIG. 5B shows a movable contact shown in FIG. It is the perspective view seen from the bottom. It is a perspective view of a general electromagnetic contactor. It is a perspective view which shows the internal structure of the electromagnetic contactor of FIG. It is a perspective view which shows the structure of a double contact type contactor apparatus, FIG. 8 (A) shows a non-contact state and FIG. 8 (B) shows a contact state. It is a perspective view which shows the state which the fibrous foreign material adhered to the fixed contact.

Explanation of symbols

160 Contact device 180 Auxiliary contact device 181 Movable contact 181a Mounting portion 181b Contact base 181c Cut groove 181d Movable contact 182 Fixed contact 182a Fixed contact 182a-1, 182a-2 Contact portion 182b Partition 282 Auxiliary contact device 282a Fixed Contact 282b Partition 380 Auxiliary contact device 381 Movable contact 381a Mounting portion 381b Contact base 381d Movable contact 381e Groove

Claims (1)

A contactor device comprising: a fixed contact having a fixed contact; and a movable contact having a plurality of movable contacts disposed to face and separate from the fixed contact,
On the contact surface of the fixed contact, a partition made of linear protrusions, and planar contact portions on both sides of the partition are formed,
Each contact of the said movable contact contacts the planar contact part of the both sides of the partition of the said fixed contact, respectively, The contact device characterized by the above-mentioned.

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