JP5914872B2 - Contact device - Google Patents

Description

  The present invention relates to a contact device in which a movable contact moves toward a fixed contact and is electrically connected by contact.

  The contact device is used for an electromagnetic relay or the like, and Patent Document 1 describes a contact device applied to an electromagnetic relay. The contact device includes a fixed terminal having a pair of fixed contacts, a movable contact having a pair of movable contacts contacting and separating from the fixed terminal, and a drive unit for moving the movable contact toward the fixed terminal. And a contact pressure spring for biasing the movable contact toward the fixed contact, and a case for housing these components.

  The drive unit includes a shaft body through which the movable contact is inserted, and a first yoke plate that is provided at one end of the shaft body and restricts the movement of the movable contact toward the fixed terminal. On the other hand, a second yoke plate is fixed to the movable contact on the side opposite to the movable contact.

  In this contact device, the first yoke plate is also displaced in the same direction by moving the shaft body in the direction of the fixed terminal by driving of the driving unit. Therefore, the movable contact is moved to the fixed terminal by the biasing force of the contact pressure spring. The movable contact and the fixed contact are brought into contact with each other and become conductive. By this conduction, a magnetic field is generated around the movable contact, and a magnetic attractive force is generated between the first yoke plate and the second yoke plate. Since this magnetic attraction force cancels the repulsive force generated by the contact of the contacts, it is possible to reduce a decrease in contact pressure between the contacts, and the movable contact and the fixed contact can be satisfactorily brought into contact with each other.

JP 2011-23332 A

  The contact device described above has a structure in which two movable contacts that come into contact with the fixed contacts are provided in pairs, and each movable contact comes into contact with the fixed contacts by the biasing force of the contact pressure spring. However, in such a structure in which two movable contacts are paired, the contact of the movable contact with the fixed contact becomes unstable due to the vibration of the movable contact due to the electromagnetic force caused by the current or the action of external vibration. .

  For this reason, it can be considered that there are three contact areas between the movable contact and the fixed contact. However, in the case where the movable contact and the fixed contact are brought into contact with each other in the three contact areas, it is difficult to make the contact in the three contact areas when the acting force on the movable contact is unevenly distributed, and stable conduction is achieved. There is a problem that cannot be done.

  Therefore, the present invention has a structure in which the movable contact and the fixed contact can be more reliably brought into contact with each other in the three contact areas when the movable contact and the fixed contact are brought into contact with each other in the three contact areas. An object is to provide a contact device.

  According to a first aspect of the present invention, there are provided a plurality of fixed terminals having a fixed contact, a movable contact that contacts the fixed contact in a detachable manner, and a movable terminal that is movable relative to the fixed terminal; A contact pressure spring that presses the movable terminal to bring the fixed contact and the movable contact into contact with each other, wherein the movable terminal is viewed from a relative movement direction of the movable terminal with respect to the fixed terminal. Is formed with three contact areas between the movable contact and the fixed contact, and is connected so that the distance between any two of the three contact areas is the shortest. The spring load center of the contact pressure spring is located on the line segment connecting the midpoint of the minute and the point where the distance from the midpoint in the other one contact area is the shortest. The gist.

According to a second aspect of the present invention, there are provided a plurality of fixed terminals having fixed contacts, a movable contact that comes into contact with and away from the fixed contact, and a movable terminal that is movable relative to the fixed terminal; A contact pressure spring that presses the movable terminal to bring the fixed contact and the movable contact into contact with each other, wherein the movable terminal is viewed from a relative movement direction of the movable terminal with respect to the fixed terminal. Are formed with three contact areas between the movable contact and the fixed contact, and the midpoint of the line segment connecting the two vertices in the triangle formed by the inner tangent lines of the three contact areas and the other A contact portion having a contact surface with which the contact pressure spring contacts is formed on the movable terminal so that a spring load center of the contact pressure spring is located on a line segment connecting to one apex of the contact pressure spring. The contact surface of the contact portion is in the direction of the line segment And summarized in that the cross-sectional shape in al visual state is a circular arc centered on the line.

A third aspect of the present invention, wherein the movable terminal, before Symbol the contact pressure spring has contact portion is formed to have a contact with abutment surface, abutment surface of the abutment, the segment The gist is that the cross-sectional shape as viewed from the direction is an arc shape centered on the line segment.
According to a fourth aspect of the present invention, the movable terminal is formed with a groove portion that accommodates one end of the contact pressure spring, and the movable terminal is viewed from the relative movement direction of the movable terminal with respect to the fixed terminal. The gist is that at least a part of the line segment is included in the groove.
The fifth feature of the present invention is summarized in that the contact portion is formed in the groove portion.

  In the present invention, the distance from the midpoint of the line segment connected so that the distance between any two abutment areas of the three abutment areas is the shortest, and the midpoint of the other one abutment area is The spring load center of the contact pressure spring is located on the line segment connecting the shortest point.

  Alternatively, the spring load center of the contact pressure spring is located on the line segment connecting the midpoint of the line connecting the two vertices in the triangle formed by the inner tangent lines of the three contact areas and the other vertex. I am doing so.

  If the position of the spring load center of the contact pressure spring is set to the above-described position, the spring load center of the contact pressure spring is located within the triangle formed by connecting the three contact areas, and is movable. The contact and the fixed contact can be more reliably brought into contact with each other in the three contact areas.

It is sectional drawing which shows the contact apparatus concerning 1st Embodiment of this invention. It is a top view which shows the movable terminal concerning 1st Embodiment of this invention. It is an AA longitudinal cross-section of FIG. It is a side view which shows the movable terminal concerning 1st Embodiment of this invention. It is a BB vertical cross section of FIG. It is a figure explaining the contact state of the contact part and contact pressure spring concerning 1st Embodiment of this invention. It is a figure explaining the contact state of the movable contact and fixed contact concerning 1st Embodiment of this invention, Comprising: It is a top view which shows the contact state of the movable contact and fixed contact in a normal state of a movable terminal. . It is a figure explaining the contact state of the movable contact and fixed contact concerning 1st Embodiment of this invention, Comprising: It is a top view which shows the contact state of the movable contact and fixed contact in the state which the movable terminal shifted. is there. It is sectional drawing which shows the contact apparatus concerning 2nd Embodiment of this invention. It is sectional drawing which shows the contact apparatus concerning 3rd Embodiment of this invention. It is a top view which shows the movable terminal concerning 3rd Embodiment of this invention. It is a top view which shows the modification of the movable terminal concerning 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that similar components are included in the following embodiments. Therefore, in the following, common reference numerals are given to those similar components, and redundant description is omitted.

(First embodiment)
The contact device 1 according to the present embodiment is applied to an electromagnetic relay. The contact device 1 includes a drive unit 2 located at the lower part in FIG. 1 and a contact part 3 located at the upper part. The drive part 2 and the contact part 3 are accommodated in a case 5.

  The case 5 includes a drive unit storage case unit 7 that opens on the contact unit 3 side, and a contact unit storage case unit 9 that closes the open side of the drive unit storage case unit 7. The case 5 may be circular in a plan view as viewed from the up and down direction in FIG. 1, or may be square or polygonal.

  The drive unit storage case unit 7 includes a lower wall 7a and a side wall 7b that rises from the periphery of the lower wall 7a toward the contact portion 3 side, and has a cup shape that opens on the contact portion 3 side. Moreover, the contact part storage case part 9 is provided with the upper wall 9a and the side wall 9b extended toward the drive part 2 side from the periphery of the upper wall 9a, and is exhibiting the cup shape which the drive part 2 side opens. .

  The drive unit 2 includes a coil 13 wound around a coil bobbin 11, and a fixed iron core 15, which is a fixing member, is disposed on the opening side of the drive unit case 7 in a through hole 11 a formed at the center of the coil bobbin 11. A movable iron core 17 that is a movable member is disposed on the lower wall 7a side opposite to the opening.

  Further, a yoke 19 is disposed between the coil 13 and the drive unit storage case unit 7. The yoke 19 includes a bottom wall 19a that faces the lower wall 7a, and a cylindrical portion 19b that is formed so as to surround the periphery of the rising coil 13 from the periphery of the bottom wall 19a and faces the side wall 7b.

  And the yoke upper board 21 is arrange | positioned so that the site | part corresponding to the coil 13 of the opening by the side of the contact part 3 of the yoke 19 may be covered.

  The fixed iron core 15 has a protrusion 15a fitted in the through hole 21a of the yoke upper plate 21 and the through hole 11a of the coil bobbin 11, and the flange portion 15b is mounted on the seat surface 21b formed on the upper portion of the yoke upper plate 21. By being placed, it is fixed to the yoke upper plate 21 and the coil bobbin 11. On the other hand, the movable iron core 17 located on the lower wall 7 a side of the fixed iron core 15 can move toward and away from the fixed iron core 15 in the through hole 11 a of the coil bobbin 11.

  A through hole 15 c and a through hole 17 a are formed in the fixed iron core 15 and the movable iron core 17, and a return spring 23 is disposed between the fixed iron core 15 and the movable iron core 17. The return spring 23 presses the movable iron core 17 in a direction away from the fixed iron core 15 (downward in FIG. 1) via the spring receiving portion 52.

  The upper end of the return spring 23 is in contact with a pressing plate 49 fixed to the upper surface of the yoke upper plate 21. A spring receiving portion 51 is disposed further above the pressing plate 49, and a contact pressure spring 33 is disposed between the spring receiving portion 51 and a movable contact 29 described later.

  The movable iron core 17 is provided with a shaft 25 extending along the moving direction of the movable iron core 17, and a movable terminal 28 is attached to the tip of the shaft 25. The movable terminal 28 is formed by a flat movable contact portion 29 and three movable contacts 31a, 31b, 31c (see FIG. 2) provided so as to protrude from the upper surface of the movable contact portion 29. The three movable contacts 31a, 31b, 31c are formed on the upper surface of the movable contact portion 29 with a distance from each other.

  In the present embodiment, a screw 55 is formed at one end of the shaft 25, and a flange portion 25a is formed at the other end. The holding plate 49, the spring receiving portions 51 and 52, and the movable contact 29 are formed with a through hole 49a into which the shaft 25 is inserted, a through hole 51a, 52a, and a through hole 29a, respectively.

  The movable terminal 28 is attached to the tip of the shaft 25 as follows.

  First, as shown in FIG. 1, the movable iron core 17, the spring receiving part 52, the return spring 23, the pressing plate 49, the spring receiving part 51, the contact pressure spring 33, and the movable terminal 28 are arranged in this order from the bottom. At this time, the return spring 23 is inserted into the through hole 15 c of the fixed iron core 15 in which the protrusion 15 a is fitted into the through hole 21 a of the yoke upper plate 21 and the through hole 11 a of the coil bobbin 11.

  Then, the screw 55 side of the shaft 25 is inserted through the through holes 29 a, 51 a, 49 a, the contact pressure spring 33, and the return spring 23 from above the movable terminal 28, and connected to the movable iron core 17 by the screw 55.

  Thus, the movable terminal 28 is attached to the tip of the shaft 25. In the present embodiment, an annular groove 29b is formed on the lower surface side of the movable contact 29, and one end of the contact pressure spring 33 is accommodated in the groove 29b.

  Moreover, the fixed contact 35 is arrange | positioned in the position facing three movable contacts 31a, 31b, 31c so that it may protrude below.

  The fixed contact 35 is fixed on a fixed terminal 37, and the fixed terminal 37 is attached to a fixed contact holding portion 41 made of an insulating resin. Note that the end of the fixed terminal 37 is an external connection terminal that is pulled out of the case 5 and connected to an external load or the like.

  In the present embodiment, the fixed terminal 37 is provided with two (plural) fixed contacts 35. Then, one fixed contact 35 (the left fixed contact 35 in FIG. 1) contacts (contacts) the movable contact 31a, and the other fixed contact 35 (the right fixed contact 35 in FIG. 1) moves to the movable contact 31b. And it contacts (contacts) the movable contact 31c. By this contact, the fixed contact 35 and the movable contacts 31a, 31b, 31c become conductive.

  At this time, when the contact pressure spring 33 presses the movable contact 29, each of the movable contacts 31a, 31b, 31c comes into contact with the fixed contact 35 with a predetermined contact pressure. The contact pressure spring 33 is set so that the spring load is lower than that of the return spring 23 described above. For this reason, in a state where the coil 13 is not energized and no driving force is applied to the movable iron core 17, the elastic force of the return spring 23 overcomes the elastic force of the contact pressure spring 33, and the movable iron core 17 is moved to the movable contact 29. At the same time, it moves in a direction away from the fixed iron core 15 to the state shown in FIG.

  Next, the operation of the contact device 1 will be described.

  First, in the state of FIG. 1 in which the coil 13 is not energized, the elastic force of the return spring 23 overcomes the elastic force of the contact pressure spring 33, the movable iron core 17 moves away from the fixed iron core 15, and the movable contact 31a. 31b and 31c are separated from the fixed contact 35 as shown in FIG. 1, and the contact device 1 is turned off.

  When the coil 13 is energized from this off state, the movable iron core 17 moves closer to the fixed iron core 15 by being attracted to the fixed iron core 15 against the elastic force of the return spring 23 by electromagnetic force. As a result, the movable contact 31 comes into contact with the fixed contact 35 and the contacts are electrically connected to each other, and the contact device 1 is turned on.

  Thus, in the present embodiment, the vertical direction in FIG. 1 is the relative movement direction of the movable terminal 28 with respect to the fixed terminal 37.

  Here, in the present embodiment, the movable terminal by the contact pressure spring 33 is positioned so that the spring load center x of the contact pressure spring 33 is located within the triangle T1 formed by connecting the three movable contacts 31a, 31b, 31c. 28 pressing parts are set.

  Specifically, as shown in FIG. 2, the movable contact 29 of the movable terminal 28 is formed to be a substantially trapezoidal flat plate, and the three movable contacts 31a, 31b, 31c are movable contacts. 29 are provided so as to be at three point positions separated from each other. In the present embodiment, the central portion in the width direction (vertical direction in FIG. 2) on one end side in the longitudinal direction of the movable contact 29 (left side in FIG. 2: the short side of the movable contact 29) protrudes upward in a substantially trapezoidal shape. By doing so, the substantially trapezoidal movable contact 31a is provided. Then, the both ends in the width direction on the other end in the longitudinal direction of the movable contact 29 (the right side in FIG. 2: the long side of the movable contact 29) are projected upward in a substantially pentagonal shape, thereby moving the substantially pentagonal shape. Contacts 31b and 31c are provided.

  Further, a through hole 29a into which the above-described shaft 25 is inserted is formed at the center in the longitudinal direction of the movable contact 29, that is, between the movable contact 31a on one side and the movable contacts 31b and 31c on the other side. Yes. An annular groove 29b is formed on the lower surface of the movable contact 29 so as to be substantially concentric with the through hole 29a.

  Further, at both ends in the longitudinal direction of the movable contact 29 in the annular groove 29b, protrusions (contact portions) 29c that protrude downward are provided, and the contact pressure springs 33 accommodated in the groove 29b. One end of this is in contact with only this projection (contact part) 29c. In other words, the contact pressure spring 33 is prevented from coming into contact with the inner surface of the groove 29b other than the portion where the projection (contact portion) 29c is formed.

  Therefore, the spring load center x of the contact pressure spring 33 is located at the middle portion between the two protrusions (contact portions) 29c, that is, at the approximate center of the groove 29b.

  The fixed contact 35 is provided in a substantially cylindrical shape, and the fixed contact 35 on one end in the longitudinal direction of the movable contact 29 abuts on the movable contact 31 a and the other end in the longitudinal direction of the movable contact 29 is provided. The fixed contact 35 on the side contacts the movable contacts 31b and 31c.

  At this time, when viewed from the up-down direction (direction of relative movement of the movable terminal 28 to the fixed terminal 37), the movable terminal 28 has contact regions R1, R2, Three R3 are formed. The contact regions R1, R2, and R3 are regions in which the movable contacts 31a, 31b, and 31c and the fixed contact 35 overlap when viewed from the vertical direction when the movable terminal 28 is in a normal state (see FIG. 7). (Hatched area).

  A triangle T1 is formed by connecting the centers of gravity G1, G2, and G3 of the contact regions R1, R2, and R3.

  Then, as shown in FIG. 7, the spring load center x of the contact pressure spring 33 is set so as to be located within a triangle T1 formed by connecting the three movable contacts 31a, 31b, 31c.

  Furthermore, in this embodiment, the spring load center x of the contact pressure spring 33 is positioned on the line segment L2 in FIG.

  This line segment L2 is a line segment drawn as follows.

  First, the distance between the contact regions R2 and R3 of any two of the three contact regions R1, R2, and R3 (the contact regions R2 and R3 that contact one fixed contact 35 in this embodiment) is A line segment connected so as to be the shortest is defined as a line segment L1. The midpoint of the line segment L1 is set as the midpoint M1. A point having the shortest distance from the middle point M1 in the other one contact region R1 is defined as a point P1. A line segment L2 is drawn by connecting the midpoint M1 and the point P1.

  The spring load center x of the contact pressure spring 33 is positioned on the line segment L2 thus drawn.

  In the present embodiment, since the movable terminal 28 is formed so as to be line-symmetric with respect to the line segment L2, the triangle T1 is an isosceles triangle, and the line segment L2 passes through the center of gravity of the triangle T1. It becomes.

  Here, the position of the spring load center x of the contact pressure spring 33 is set as follows.

  First, the groove portion 29b is formed so as to include at least a part of a straight line including the line segment L2 when viewed from the relative movement direction of the movable terminal 28 with respect to the fixed terminal 37. In the present embodiment, the annular groove 29b is formed so that a straight line including the line segment L2 passes through the center. At this time, the groove 29b is divided into two by the line segment L2.

  Then, in a state viewed from the relative movement direction of the movable terminal 28 with respect to the fixed terminal 37, a protrusion (contact portion) 29 c with which one end of the contact pressure spring 33 comes into contact with the region 29 b including the line segment L 2 and in the groove portion 29 b. Form.

  Then, the shape of the contact surface 29d with which one end of the contact pressure spring 33 of the protrusion (contact portion) 29c contacts is centered on a straight line including the line segment L2 in the cross-sectional shape when viewed from the direction of the line segment L2. To be arcuate.

  In the present embodiment, a part of a cylinder having the line segment L2 as an axis is a protrusion (contact portion) 29c.

  In this way, when one end of the contact pressure spring 33 comes into contact with the contact surface 29d of the projection (contact portion) 29c, the pressing directions of the spring loads of the two contact pressure springs 33 both pass the line segment L2. Thus, the spring load center x of the contact pressure spring 33 is positioned on the line segment L2.

  As described above, in the present embodiment, the midpoint of the line segment L1 connected so that the distance between any two contact regions R2, R3 among the three contact regions R1, R2, R3 is the shortest. The spring load center x of the contact pressure spring 33 is positioned on a line segment L2 connecting M1 and the point P1 that has the shortest distance from the middle point M1 in the other one contact region R1. .

  Thus, if the position of the spring load center x of the contact pressure spring 33 is set on the line segment L2, the spring load center x of the contact pressure spring 33 is formed by connecting the three movable contacts 31a, 31b, 31c. It will be located in the triangle T1.

  By the way, if the spring load center x of the contact pressure spring 33 is located outside the triangle T1, when the movable contacts 31a, 31b, 31c are brought into contact with the fixed contact 35, the movable terminal 28 of the contact pressure spring 33 is moved. Any one of the movable contacts is rotated in a direction away from the fixed contact 35 by the pressing. Therefore, it becomes difficult for all of the three movable contacts 31a, 31b, and 31c to come into contact with the fixed contact 35, and there is a problem that stable conduction cannot be achieved. Further, there is also a problem that the vibration of the movable terminal 28 is increased when the contact device 1 is turned on due to the rotation of the movable terminal 28, and the noise is increased.

  However, in this embodiment, the spring load center x of the contact pressure spring 33 is positioned within the triangle T1. Therefore, all the three movable contacts 31a, 31b, 31c can be pressed toward the fixed contact 35 by the contact pressure spring 33, and all the three movable contacts 31a, 31b, 31c are fixed to the fixed contact 35. It becomes possible to make it contact reliably by. That is, the movable contacts 31a, 31b, 31c and the fixed contact 35 can be more reliably brought into contact with each other in the three contact areas R1, R2, R3. Furthermore, since the rotation of the movable terminal 28 is suppressed, the noise of the contact device 1 can be suppressed.

  Furthermore, in this embodiment, the position of the spring load center x of the contact pressure spring 33 is set on the line segment L2. Therefore, as shown in FIG. 8, even when the movable terminal 28 is displaced (rotated) and contacts (contacts) the fixed contact 35, the spring load center x of the contact pressure spring 33 is 3 It can be located within the square T1.

  That is, according to the present embodiment, the allowable positional deviation range of the movable terminal 28 can be widened. Specifically, if all three movable contacts 31a, 31b, 31c are in contact with the fixed contact 35, the spring load center x of the contact pressure spring 33 may be positioned within the triangle T1. it can. Therefore, all the three movable contacts 31a, 31b, 31c can be brought into contact with the fixed contact 35 more reliably.

  In the present embodiment, the movable terminal 28 is formed with a groove 29b in which one end of the contact pressure spring 33 is accommodated.

  Then, at least a part of the line segment L2 is included in the groove 29b when viewed from the relative movement direction of the movable terminal 28 with respect to the fixed terminal 35.

  And the protrusion part (contact part) 29c which has the contact surface 29d with which the contact pressure spring 33 contact | abuts is formed in the groove part 29b.

  The contact surface 29d of the protrusion (contact portion) 29c is formed such that the cross-sectional shape in the state viewed from the direction of the line segment L2 is an arc shape centered on the line segment L2.

  In this way, by forming the protrusion (contact portion) 29c, the pressing direction of the spring load of the contact pressure spring 33 is linear even if the contact pressure spring 33 contacts any portion of the contact surface 29d. It will pass through the minute L2. Therefore, the displacement of the spring load center x of the contact pressure spring 33 due to contact with the contact surface 29d in a state where the contact pressure spring 33 is displaced can be suppressed as much as possible. The movable contacts 31a, 31b, and 31c can be brought into contact with the fixed contact 35.

(Second Embodiment)
The contact device 1A according to the present embodiment has substantially the same configuration as that of the first embodiment, and is applied to an electromagnetic relay.

  That is, the contact device 1 </ b> A includes a drive unit 2 located at the lower part and a contact part 3 located at the upper part in FIG. 9, and the drive part 2 and the contact part 3 are accommodated in the case 5.

  The drive unit 2 includes a coil 13 wound around a coil bobbin 11, and a fixed iron core 15 as a fixing member is placed on the lower wall 7 a side of the drive unit case 7 in a through hole 11 a formed at the center of the coil bobbin 11. The movable iron core 17 that is a movable member is disposed on the opening side opposite to the lower wall 7a. Thus, in this embodiment, the arrangement positions of the fixed iron core 15 and the movable iron core 17 are opposite to those in the first embodiment.

  And the yoke 19 is arrange | positioned between the coil 13 and the drive part storage case part 7. FIG. The yoke 19 includes a bottom wall 19a that faces the lower wall 7a, and a cylindrical portion 19b that is formed so as to surround the periphery of the rising coil 13 from the periphery of the bottom wall 9a and that faces the side wall 7b.

  And the yoke upper board 21 is arrange | positioned so that the site | part corresponding to the coil 13 of the opening by the side of the contact part 3 of the yoke 19 may be covered. The yoke upper plate 21 has an outer peripheral edge fixed to the end of the cylindrical portion 19 b of the yoke 19, and a cylindrical portion 21 a protruding downward from the inner peripheral edge is provided between the movable iron core 17 and the coil bobbin 11. Has been inserted. For this reason, as for the coil bobbin 11, a part by the side of the contact part 3 which inserted the cylinder part 21a of the yoke upper board 21 has the internal diameter of the through-hole 11a larger than the other site | part of the lower part.

  The fixed iron core 15 is fixed to the yoke 19 by fitting the projection 15a into a fitting hole 19c formed at the center of the bottom wall 19a of the yoke 19. On the other hand, the movable iron core 17 located on the contact portion 3 side of the fixed iron core 15 can move toward and away from the fixed iron core 15 in the through hole 11 a of the coil bobbin 11.

  On the opposite sides of the fixed iron core 15 and the movable iron core 17, a recess 15b and a recess 17a are formed, and a return spring 23 is disposed between the recesses 15b and 17a. The return spring 23 presses the movable iron core 17 in a direction away from the fixed iron core 15.

  On the opposite side of the movable iron core 17 to the fixed iron core 15, a shaft 25 is provided so as to extend along the moving direction of the movable iron core 17. The shaft 25 may be formed integrally with the movable iron core 17 or may be formed as a separate body and fixed to the movable iron core 17.

  A movable terminal 28 is attached to the tip of the shaft 25 via a boss portion 27.

  The movable terminal 28 includes a plate-shaped movable contact portion 29 attached to the boss portion 27 and three movable contacts 31a, 31b, 31c (see FIG. 5) provided so as to protrude from the lower surface of the movable contact portion 29 on the driving portion 2 side. 2). That is, in the present embodiment, the movable terminal 28 not provided with the through hole 29a is disposed on the boss portion 27 in a state where the side where the groove portion 29b is formed is the upper surface, contrary to the first embodiment. It is attached.

  Moreover, the fixed contact 35 is arrange | positioned in the position which opposes the drive part 2 side of the three movable contacts 31a, 31b, and 31c so that it may protrude on an upper surface. The fixed contact 35 is fixed on a fixed terminal 37, and the fixed terminal 37 is attached to a fixed contact holding portion 41 made of an insulating resin. The end of the fixed terminal 37 is an external connection terminal that is pulled out of the case 5 and connected to an external load or the like.

  In the present embodiment, the fixed terminal 37 is provided with two (plural) fixed contacts 35. Then, one fixed contact 35 (the left fixed contact 35 in FIG. 9) contacts (contacts) the movable contact 31a, and the other fixed contact 35 (the right fixed contact 35 in FIG. 9) contacts the movable contact 31b. And it contacts (contacts) the movable contact 31c. By this contact, the fixed contact 35 and the movable contacts 31a, 31b, 31c become conductive.

  At this time, when the contact pressure spring 33 presses the movable contact 29, each of the movable contacts 31a, 31b, 31c comes into contact with the fixed contact 35 with a predetermined contact pressure. The contact pressure spring 33 is set so that the spring load is lower than that of the return spring 23 described above. For this reason, in a state where the coil 13 is not energized and no driving force is applied to the movable iron core 17, the elastic force of the return spring 23 overcomes the elastic force of the contact pressure spring 33, and the movable iron core 17 is moved to the movable contact 29. At the same time, it moves in a direction away from the fixed iron core 15 to a state shown in FIG.

  Next, the operation of the contact device 1A will be described.

  First, in the state of FIG. 9 in which the coil 13 is not energized, the elastic force of the return spring 23 overcomes the elastic force of the contact pressure spring 33, the movable iron core 17 moves away from the fixed iron core 15, and the movable contact 31a. , 31b, 31c are separated from the fixed contact 35 as shown in FIG. 9, and the contact device 1A is turned off.

  When the coil 13 is energized from this off state, the movable iron core 17 moves closer to the fixed iron core 15 by being attracted to the fixed iron core 15 against the elastic force of the return spring 23 by electromagnetic force. As a result, the movable contact 31 comes into contact with the fixed contact 35 and the contacts are electrically connected to each other, and the contact device 1A is turned on.

  Thus, in the present embodiment, the vertical direction in FIG. 9 is the relative movement direction of the movable terminal 28 with respect to the fixed terminal 37.

  Here, in the present embodiment, the movable terminal by the contact pressure spring 33 is positioned so that the spring load center x of the contact pressure spring 33 is located within the triangle T1 formed by connecting the three movable contacts 31a, 31b, 31c. 28 pressing parts are set.

  Specifically, the movable contact 29 of the movable terminal 28 is formed to be a substantially trapezoidal flat plate as in the first embodiment, and the three movable contacts 31a, 31b, 31c are movable. It is provided on the contactor 29 so as to be at three point positions separated from each other (see FIG. 2).

  Also in this embodiment, the central portion in the width direction (vertical direction in FIG. 2) on one end side of the movable contact 29 in the longitudinal direction (left side in FIG. 2: short side of the movable contact 29) protrudes upward in a substantially trapezoidal shape. By doing so, the substantially trapezoidal movable contact 31a is provided. Then, the both ends in the width direction on the other end in the longitudinal direction of the movable contact 29 (the right side in FIG. 2: the long side of the movable contact 29) are projected upward in a substantially pentagonal shape, thereby moving the substantially pentagonal shape. Contacts 31b and 31c are provided.

  Further, an annular groove 29 b is formed on the lower surface of the movable contact 29. In the present embodiment, the movable contact 29 is not provided with a through hole.

  Further, at both ends in the longitudinal direction of the movable contact 29 in the annular groove 29b, protrusions (contact portions) 29c that protrude downward are provided, and the contact pressure springs 33 accommodated in the groove 29b. One end of this is in contact with only this projection (contact part) 29c. In other words, the contact pressure spring 33 is prevented from coming into contact with the inner surface of the groove 29b other than the portion where the projection (contact portion) 29c is formed.

  Therefore, the spring load center x of the contact pressure spring 33 is located at the middle portion between the two protrusions (contact portions) 29c, that is, at the approximate center of the groove 29b.

  The fixed contact 35 is provided so as to have a substantially cylindrical shape.

  At this time, when viewed from the up-down direction (direction of relative movement of the movable terminal 28 to the fixed terminal 37), the movable terminal 28 has contact regions R1, R2, Three R3 are formed.

  A triangle T1 is formed by connecting the centers of gravity G1, G2, and G3 of the contact regions R1, R2, and R3.

  Also in the present embodiment, the spring load center x of the contact pressure spring 33 is set so as to be positioned within a triangle T1 formed by connecting the three movable contacts 31a, 31b, 31c (see FIG. 7). ).

  Specifically, the midpoint M1 of the line segment L1 connected so that the distance between any two of the three contact regions R1, R2, and R3 is the shortest, and another one The spring load center x of the contact pressure spring 33 is positioned on a line segment L2 connecting the point P1 having the shortest distance from the middle point M1 in the two contact regions R1.

  Also in the present embodiment, the contact surface 29d of the protrusion (contact portion) 29c is formed so that the cross-sectional shape when viewed from the direction of the line segment L2 is an arc shape centered on the line segment L2. doing.

  Also according to this embodiment described above, the same operations and effects as those of the first embodiment can be achieved.

(Third embodiment)
The contact device 1B according to the present embodiment has substantially the same configuration as that of the second embodiment.

  That is, the contact device 1 </ b> B also includes a drive unit 2 positioned at the bottom in FIG. 10 and a contact unit 3 positioned at the top, and the drive unit 2 and the contact unit 3 are accommodated in the case 5. .

  The drive unit 2 includes a coil 13 wound around a coil bobbin 11, and a fixed iron core 15 as a fixing member is placed on the lower wall 7 a side of the drive unit case 7 in a through hole 11 a formed at the center of the coil bobbin 11. The movable iron core 17 that is a movable member is disposed on the opening side opposite to the lower wall 7a. Thus, also in this embodiment, the arrangement positions of the fixed iron core 15 and the movable iron core 17 are opposite to those in the first embodiment.

  Also in this embodiment, the vertical direction in FIG. 10 is the relative movement direction of the movable terminal 28 with respect to the fixed terminal 37.

  Here, the contact device 1B according to the present embodiment is mainly different from the second embodiment in that three contact points 1a, 31b, 31c provided on the movable terminal 28 are opposed to each other. One fixed contact point 35 is formed.

  The movable terminal 28 is formed with three contact areas of the movable contacts 31 a, 31 b, 31 c and the fixed contact 35 as viewed from the relative movement direction of the movable terminal 28 with respect to the fixed terminal 37. In the present embodiment, since the three fixed contacts 35 are formed at positions facing the movable contacts 31a, 31b, and 31c, the movable contacts 31a, 31b, and 31c have circular contact areas R1, R2, R3.

  In this embodiment, the inner tangents of the contact areas R1, R2, and R3 (tangent lines formed on the other contact area side among the common tangent lines formed in the two contact areas) are L3, L4, and L5. The spring load center x of the contact pressure spring 33 is positioned in the formed triangle T2.

  Furthermore, in this embodiment, the spring load center x of the contact pressure spring 33 is positioned on the line segment L7 in the triangle T2.

  Specifically, a triangle formed by the inner tangents L3, L4, and L5 of the three contact regions R1, R2, and R3 is defined as a triangle T2. A line segment connecting two vertices (lower vertices in FIG. 11) P2 and P3 in the triangle T2 is defined as a line segment L6. A line segment connecting the midpoint M2 of the line segment L6 and another vertex P4 is defined as a line segment L7, and the spring load center x of the contact pressure spring 33 is positioned on the line segment L7.

  Also in this embodiment, the contour shape of the movable terminal 28 is the same as the contour shape of the movable terminal 28 of the first and second embodiments, and is symmetrical with respect to the straight line including the line segment L7. Therefore, the triangle T2 is an isosceles triangle.

  As described above, in this embodiment, the midpoint of the line segment L6 connecting the two vertices P2 and P3 in the triangle T2 formed by the inner tangent lines L3, L4, and L5 of the three contact regions R1, R2, and R3. The spring load center x of the contact pressure spring 33 is positioned on a line segment L7 connecting M2 and the other vertex P4.

  Thus, if the position of the spring load center x of the contact pressure spring 33 is set on the line segment L2, the spring load center x of the contact pressure spring 33 connects the centers of the three movable contacts 31a, 31b, 31c. It will be located in the triangle T1 formed by.

  Therefore, all the three movable contacts 31a, 31b, 31c can be pressed toward the fixed contact 35 by the contact pressure spring 33, and all the three movable contacts 31a, 31b, 31c are fixed to the fixed contact 35. It becomes possible to make it contact reliably by. That is, the movable contacts 31a, 31b, 31c and the fixed contact 35 can be more reliably brought into contact with each other in the three contact areas R1, R2, R3. Furthermore, since the rotation of the movable terminal 28 is suppressed, the noise of the contact device 1 can be suppressed.

  In the present embodiment, the groove portion is not provided in the movable terminal 28 and one end of the contact pressure spring 33 is brought into contact with the upper surface of the movable terminal 28. However, as in the first and second embodiments. A groove portion may be provided so that one end of the contact pressure spring 33 is accommodated in the groove portion. At this time, a protrusion (contact portion) is provided in the groove portion, and the contact surface is formed so that the cross-sectional shape in a state viewed from the direction of the line segment L7 is an arc shape centered on the line segment L7. Is preferred.

  Next, a modification of the movable terminal will be described.

  In the third embodiment, as shown in FIG. 11, the triangle T1 formed by connecting the centers of the three movable contacts 31a, 31b, and 31c is an isosceles triangle, but FIG. As shown, the three movable contacts 31a, 31b, and 31c may be arranged so that the triangle T1 formed by connecting the centers of the three movable contacts 31a, 31b, and 31c becomes a right triangle.

  Even in this case, the midpoint M2 of the line segment L6 connecting the two vertices P2 and P3 in the triangle T2 formed by the inner tangents L3, L4, and L5 of the three contact regions R1, R2, and R3 and other points If the spring load center x of the contact pressure spring 33 is positioned on the line segment L7 connecting one vertex P4, a triangle formed by connecting the centers of the three movable contacts 31a, 31b, 31c. The spring load center x of the contact pressure spring 33 can be arranged in T1.

  That is, even if the arrangement of the three movable contacts 31a, 31b, 31c is the arrangement shown in FIG. 11, the same operations and effects as those of the third embodiment can be achieved.

  In the first and second embodiments, the positions of the three movable contacts 31a, 31b, and 31c may be arranged so that the triangle T1 is a right triangle.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various modifications can be made.

  For example, in each of the above-described embodiments, the projection is formed so that the shape of the protrusion becomes a part of a cylinder.

  Further, the three movable contacts can be arranged so that not only isosceles triangles and right triangles but also other triangles are formed.

  Further, movable terminals, fixed terminals, and other detailed specifications (shape, size, layout, etc.) can be changed as appropriate.

1, 1A, 1B Contact device 28 Movable terminals 31a, 31b, 31c Movable contact 33 Contact pressure spring 35 Fixed contact 37 Fixed terminal x Spring load center

Claims (5)

A plurality of fixed terminals having fixed contacts, a movable contact that contacts the fixed contacts in a detachable manner, a movable terminal that can move relative to the fixed terminals, and the fixed contacts by pressing the movable terminals And a contact pressure spring for contacting the movable contact,
When viewed from the relative movement direction of the movable terminal with respect to the fixed terminal, the movable terminal is formed with three contact areas between the movable contact and the fixed contact,
The midpoint of the line segment connected so that the distance between any two of the three contact areas is the shortest, and the distance from the midpoint in the other one of the contact areas is the shortest The contact load device is characterized in that the spring load center of the contact pressure spring is located on a line segment connecting the point. A plurality of fixed terminals having fixed contacts, a movable contact that contacts the fixed contacts in a detachable manner, a movable terminal that can move relative to the fixed terminals, and the fixed contacts by pressing the movable terminals And a contact pressure spring for contacting the movable contact,
When viewed from the relative movement direction of the movable terminal with respect to the fixed terminal, the movable terminal is formed with three contact areas between the movable contact and the fixed contact,
The spring load center of the contact pressure spring is located on the line segment connecting the midpoint of the line segment connecting the two vertices in the triangle formed by the inner tangent lines of the three contact areas and the other vertex. the way,
The movable terminal is formed with a contact portion having a contact surface with which the contact spring contacts.
The contact surface of the contact portion is a contact device characterized in that a cross-sectional shape in a state viewed from the line segment direction is an arc shape centered on the line segment . Wherein the movable terminal has abutment portion is formed with a contact surface before Symbol contact pressure spring abuts,
The abutment surface of the abutment portion, the contact device of claim 1, the cross-sectional shape in a state viewed from the line direction, characterized in that an arc shape centered the line segment. The movable terminal is formed with a groove portion that accommodates one end of the contact pressure spring,
The at least one part of the said line segment is contained in the said groove part in the state seen from the relative movement direction with respect to the said fixed terminal of the said movable terminal, The any one of Claims 1-3 characterized by the above-mentioned. Contact device. The contact device according to claim 4, wherein the contact portion is formed in the groove portion.

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