JPH08250002A - Shock absorber of electromagnetic contactor - Google Patents

Abstract

PURPOSE: To reduce a sound on a board when closing an electromagnetic contactor. CONSTITUTION: A slide 22 is housed in a housing 21, bottom plate supports 18 having shock absorber springs 23 are installed from both sides to the side wall of the main body frame 1 of an electromagnetic contactor, and a bottom plate 14 is held by engaging the engaging piece 14a of the bottom plate 14 installing a fixed iron core 3, to the groove of the slide 22, so as to hold the fixed iron core 3 to the main body frame 1 through a shock absorber spring 23. Consequently, a shock generated to the fixed iron core 3 when a movable iron core 4 is attracted is absorbed by the shock absorber spring 23, so as to relax the shock to the installation panel P of the board, and the sound generated on the board can be suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic contactor, and more particularly to a shock absorber for reducing the noise of a panel during the closing operation of a large electromagnetic contactor.

[0002]

2. Description of the Related Art FIGS. 10 and 11 show a conventional example of a large-sized (for example, a rated current carrying capacity of 135 A or more) three-pole electromagnetic contactor. FIG. 10 is a longitudinal sectional view and FIG. It is sectional drawing which follows the XI line. In the figure, an electromagnet including a fixed iron core 3 having an electromagnetic coil 2 mounted thereon and a movable iron core 4 facing the fixed iron core 3 is installed on a main body frame 1 having an opening on a mounting surface (lower surface in the drawing) side. Movable iron core 4
A contact support 5 is connected to the contact support 5 via a connecting pin 6, and a metal fitting 8 holding the movable contact 7 is inserted into the contact support 5 so as to be slidable in the vertical direction in the drawing. Receiving piece 5
It is held by a contact spring 9 composed of a compression coil spring inserted between a and the bottom of the metal fitting 7. Each movable contact 7 is provided with a pair of fixed contacts 10 in front and back (left and right in FIG. 10), and the fixed contacts 10 are fixed to the body frame 1 integrally with the terminal plate 11 by screws. The movable iron core 4 is a receiving member 12 (see FIG. 1) fixed to the body frame 1.
The return spring 13 is inserted between the fixed core 3 and the fixed spring 3.

The fixed iron core 3 is attached to a bottom plate 14 that closes an opening on the attachment surface side of the main body frame 1, and the bottom plate 14 is fastened to the main body frame 1 by screws (not shown). The bottom plate 14 is made of a steel plate, and a pair of left and right hooks 14 a (FIG. 11) are cut and raised in an inverted L shape so as to be located on both sides of the fixed iron core 3. The fixed iron core 3 is placed at the center of the bottom plate 14 via a tray-shaped mounting seat 15 made of a resin molded product, and is fixed by a holding spring 16. The presser spring 16 is a frame-shaped leaf spring having the shape shown in FIG.
(Upper and lower sides of 2) are pressed against the front and rear flange portions 3a of the fixed iron core 3 via the spring receiving pieces 17, and the left and right concave bent portions 16b are hooked on the lower side of the hook 14a (FIG. 11). The fixed iron core 3 is pressed and fixed.

The illustrated electromagnetic contactor is attached to an attachment plate P of a board (not shown) by screws. When the electromagnetic coil 2 is excited during the closing operation, the movable iron core 4 is attracted to the fixed iron core 3 against the return spring 13, and the movable contactor 7 held by the contactor support 5 integrated with the movable iron core 4 becomes It advances in the downward direction of the figure and contacts the fixed contact 10 and bridges between the paired fixed contacts 10 to close the electric path of each pole. that time,
The contact spring 9 is compressed to generate an appropriate contact pressure.
Then, when the electromagnetic coil 2 is demagnetized, the movable iron core 4 is pushed back by the force of the return spring 13, the movable contactor 7 returns to the position shown, and the electric path is opened.

[0005]

In the closing operation of the electromagnetic contactor, the attracted movable iron core 4 collides with the fixed iron core 3 and stops, but the speed at the time of collision reaches several meters per second. In that case, since the mass of the fixed iron core 3 is at most about 1.5 times that of the movable iron core 4, its impact absorption is small, and the impact force on the fixed iron core 3 is transmitted from the main body frame 1 to the board with almost no attenuation. Therefore, conventionally, the board vibrates to generate a loud noise, which is a source of noise in a place where a house and a factory coexist, and it is an urgent need to take countermeasures in the recent situation where consideration for the environment is required. Conventionally, as a countermeasure against this, there is an example in which a cushioning member such as rubber is inserted between the body frame mounting surface of the electromagnetic contactor and the mounting plate of the board. Since the deflection changes, there are problems that a stable effect cannot be obtained and that firm mounting cannot be performed. Therefore, an object of the present invention is to provide a shock absorber for an electromagnetic contactor, which reduces shock generated when a movable iron core is attracted to reduce the noise generated by the electromagnetic contactor mounting board.

[0006]

According to the present invention, an electromagnet for driving a movable contactor by attracting a movable iron core in a direction perpendicular to the mounting surface is provided in a main body frame having an opening on the mounting surface side. The fixed iron core is an electromagnetic contactor attached to the bottom plate that closes the attachment surface side opening of the main body frame, and the bottom plate to which the fixed iron core is attached is held by the main body frame so as to be movable in the suction direction of the movable iron core. The above object is achieved by inserting a cushioning member that absorbs an impact at the time of attracting the movable iron core between the bottom plate and the bottom plate.

In the above structure, while the engaging pieces parallel to the mounting surface of the main body frame are formed on both sides of the bottom plate,
A slide plate having a groove formed corresponding to the engaging piece is slidably accommodated in the housing, and a buffer spring is inserted between the slide plate and the housing. Assembling is improved by removably mounting the bottom plates on the side walls facing each other in the vicinity from the outside, and holding the bottom plates by holding the engaging pieces in the grooves of the slide pieces of the bottom plate supports. Further, if a vibration absorbing member, a mass increasing member or a cushioning member is attached to the back surface of the bottom plate, the cushioning action is further enhanced.

[0008]

In the prior art, since there is no buffering means between the fixed iron core and the main body frame, the impact generated on the fixed iron core is directly transmitted to the main body frame, which is further transmitted to the mounting board to generate a loud noise. Therefore, in the present invention, the bottom plate to which the fixed iron core is attached is held by the main body frame so as to be movable in the suction direction of the movable iron core, and a cushioning member such as a spring is inserted between the main body frame and the bottom plate. According to this structure, the shock generated in the fixed iron core is absorbed by the cushioning member and is less likely to be transmitted to the main body frame, and the main body frame and the bottom plate are integrally floated from the main body frame. The mass of the fixed iron core portion including is increased, and the shock absorbing property of itself is also improved.

In this case, a bottom plate support in which a slide piece and a buffer spring are housed in a housing is detachably attached to the main body frame from the outside, and an engaging piece of the bottom plate is held by a groove of the slide piece to attach a fixed iron core. With this configuration, the bottom plate can be held simply by attaching the bottom plate support to the body frame after inserting the bottom plate integrated with the fixed iron core from the mounting surface opening of the body frame, so the assembly work is easy and the bottom plate Since the bottom plate can be removed by removing the support, it is easy to replace the electromagnetic coil due to changes in specifications. On the other hand, if a vibration absorbing member such as a lead plate or vibration absorbing rubber or a mass increasing member such as an iron plate is attached to the back surface of the bottom plate, the shock absorbing property of the bottom plate itself is improved and the cushioning action is further enhanced. If a cushioning member such as cushion rubber is attached to the back surface of the bottom plate and the cushioning member is brought into contact with the mounting plate of the board, a double cushioning member is provided in addition to the cushioning member between the bottom plate and the body frame. In this case, the cushioning action is further enhanced.

[0010]

Embodiments of the present invention will be described below with reference to FIGS. Note that the same reference numerals are used for the portions corresponding to the conventional example. FIG. 1 is a cross-sectional view of an electromagnetic contactor corresponding to FIG. 11 of a conventional example, and FIG. 2 is a perspective view of the mounted state of the electromagnetic contactor of FIG. 1, in which fixed iron core 3 is attached to a bottom plate 14, The bottom plate 14 is held by a bottom plate support 18 attached to the body frame 1. Figure 3-
FIG. 6 shows detailed configurations of the bottom plate 14 and the bottom plate support 18. Here, FIG. 3 is an exploded perspective view of the bottom plate 14 to which the fixed iron core 3 is attached and the bottom plate support 18, FIG. 4 is an exploded perspective view of the bottom plate support 18 seen from a direction different from FIG. 3, and FIG. A front view and FIG. 6 are sectional views taken along the line VI-VI.

In FIG. 3, the bottom plate 14 is made of a square steel plate, and the engaging pieces 14b are formed by cutting and bending in an inverted L shape on both left and right sides. In addition, a pair of left and right mounting pieces 14c are formed by cutting and bending in an inverted L shape on the sides of the front and rear (upper and lower in FIG. 2) flanges 3a in accordance with the mounting position of the fixed iron core 3. A pair of left and right positioning pieces 14d are formed by cutting and bending upright so as to contact the connecting plate 3b. Although the fixed iron core 3 has a U-shape,
The L-shape is formed by abutting two L-shaped cores, and these L-shaped cores are connected to each other by riveting via a connecting plate 3b. And the fixed iron core 3
Is placed on the bottom plate 14 as shown, and the left and right mounting pieces 14c
The flange portion 3a is pressed and fixed by the holding plate 20 that is tightened by the screw 19 across the. here,
The left and right positioning of the fixed core 3 with respect to the bottom plate 14 is performed by a positioning piece 14d, and the front and rear positioning is performed by a holding plate 20.

Next, referring to FIGS. 4 to 6, the bottom plate support 18
Is composed of a housing 21 and a slide piece 22 made of a molding resin formed in the illustrated shape, and a buffer spring 23 made of a compression coil spring. Housing 21
Has a reverse convex space 21a having an open front surface, a ridge 21b and a claw 21c at the tip thereof are formed on the left and right side surfaces, and a square hole 21d and a slit-like recess 21e are formed on the upper surface. On the other hand, the slide piece 22 has a groove 22a.
A U-shaped stopper protrusion 22b having a triangular cross section is formed on the upper surface. Further, although not visible in FIG. 4, a columnar low spring receiving projection 22c (see FIG. 6) into which the buffer spring 23 is fitted is formed on the lower surface. Slide piece 22
The buffer spring 23 having one end fitted in the spring receiving projection 22c is inserted into the space 21a of the housing 21 while bending the buffer spring 23 in the direction of the arrow in FIG. 4, and the retaining projection 22b has the square hole 21d. It is elastically fitted into and is assembled in the state shown in FIGS.

In the combined state of FIGS. 5 and 6, the front surface of the slide piece 22 is flush with the front surface of the housing 21, and the left and right side surfaces are slidable with respect to the left and right wall surfaces of the space 21a with a slight clearance. ing. Further, between the lower surface of the slide piece 22 pressed against the upper wall surface of the space 21a by the buffer spring 23 and the stepped surface of the space 21a,
There is an appropriate gap s of about 5 to mm. On the other hand, on the left and right side walls of the mounting flange portion 1a at the bottom of the main body frame 1 of the electromagnetic contactor, as shown in FIGS.
A notched window along the contour of No. 1 is provided so that the mounting surface side is open, and although not shown, the housing 21 is provided on the inner wall surface thereof.
An engaging step portion is formed with which the claw 21c is engaged. The bottom plate support 18 is inserted into the cutout window along the direction of the arrow shown in FIG. 3, and the claws 21c are engaged with the locking step portions and are prevented from coming off.

Under the above structure, the fixed iron core 3 is put in the state of FIG.
When the bottom plate 14 attached with the bottom plate 14 is inserted into the main body frame 1 through the opening on the mounting surface side, the bottom plate supports 18 are attached from the left and right sides, and at that time, the bottom plate 1 is inserted into the groove 22a of the slide piece 22.
The engaging piece 14b of No. 4 is gripped. As a result, the bottom plate 14 is held by the bottom plate support 18 from both sides as shown in FIG. The upper edge of the cutout window of the main body frame 1 is chamfered, and the chamfered portion 1a faces the recess 21e of the housing 21 as shown in FIG. FIG.
In the electromagnetic contactor, when the movable iron core 4 collides with the fixed iron core 3 during the closing operation, the fixed iron core 3 causes the buffer spring 23
While flexing, move only the stroke of the gap s in Fig. 5,
During that time, the shock is absorbed. Next buffer spring 23
The restoring force returns to the illustrated state.

According to this structure, since the impact from the bottom plate 14 is not directly transmitted to the main body frame 1, the impact applied from the main body frame 1 to the board is small and no loud noise is generated on the board. . In addition, the bottom plate 14 can be taken out by inserting the tip of a tool such as a screwdriver into the recess 21e through the gap 25 (FIG. 3) formed by the above chamfering, and then prying the bottom plate support 18 to remove the bottom plate 14. It is easy to deal with the case where it is desired to replace the electromagnetic coil 2.

FIG. 7 shows an embodiment in which a vibration absorbing member 24 made of vibration absorbing rubber or a lead plate is attached to the back surface (mounting surface side) of the bottom plate 14 in the above-described embodiment by screwing. With such a configuration, the vibration based on the impact energy applied to the fixed iron core 3 is absorbed by both the bottom plate 14 and the vibration absorbing member 24 and converted into thermal energy, and the impact transmitted to the main body frame 1 is further reduced. To be done. Even if a mass increasing member made of an iron plate or the like is attached instead of the vibration absorbing member 24 and the mass of the fixed iron core portion is increased, the same effect can be obtained.

8 is replaced with the vibration absorbing member 24 of FIG.
A cushioning member 26 made of cushion rubber is provided on the back surface of the bottom plate 14.
2 shows an example in which is attached with an adhesive. The cushioning member 26 is in contact with the mounting plate P of the board in a slightly compressed state in the released state of the electromagnetic contactor. With such a configuration, the cushioning member 26 is doubly provided in addition to the cushioning spring 23, and the cushioning spring 23 and the cushioning member 26 cooperate to absorb the shock when the electromagnetic contactor operates. Therefore, the cushioning action becomes stronger than that of the cushioning spring 23 alone.

Finally, FIG. 9 is a perspective view showing an embodiment of a fixed core portion in which the bottom plate 14 and the fixed core 3 are integrally formed. That is, the bottom plate 14 and the fixed iron core 3 are integrally formed into the illustrated shape by cold forging or sintering. With such a configuration, the process can be simplified in terms of both component processing and assembly, and the cost can be significantly reduced. This integrated component is particularly effective for direct current operated electromagnetic contactors.

[0019]

According to the present invention, the shock generated in the fixed core at the time of attracting the movable iron core is absorbed by the cushioning member inserted between the bottom plate and the main body frame, and the bottom plate is integrated with the main body frame. Since the mass of the fixed core portion is increased by the amount corresponding to the bottom plate, the vibration absorption of the plate itself is increased, and the shock transmitted to the mounting plate of the board is moderated to suppress the generation of sound in the board. In that case, a bottom plate support accommodating a slide piece together with a buffer spring is detachably attached to the main body frame from the outside, and an engaging piece of the bottom plate is held by a groove of the slide piece to hold the bottom plate to which a fixed iron core is attached. This simplifies insertion and removal of the fixed iron core, and facilitates work such as assembling and changing the electromagnetic coil due to specification changes. Further, by attaching the vibration absorbing member, the mass increasing member, and the cushioning member to the back surface of the bottom plate, the cushioning action is further enhanced.

[Brief description of drawings]

FIG. 1 is a sectional view of an electromagnetic contactor showing an embodiment of the present invention.

FIG. 2 is a perspective view of the electromagnetic contactor of FIG. 1 in an attached state showing the appearance thereof.

FIG. 3 is a perspective view of a bottom plate portion in FIG.

FIG. 4 is an exploded perspective view of the bottom plate support in FIG.

5 is a front view of the bottom plate support of FIG. 4 in an assembled state.

6 is a vertical cross-sectional view taken along the line VI-VI of FIG.

FIG. 7 is a cross-sectional view of essential parts of an electromagnetic contactor showing an embodiment in which a vibration absorbing member is attached to the back surface of the bottom plate in FIG.

8 is a cross-sectional view of essential parts of an electromagnetic contactor showing an embodiment in which a buffer member is attached to the back surface of the bottom plate in FIG.

FIG. 9 is a perspective view showing an embodiment in which a fixed iron core and a bottom plate are integrally configured.

FIG. 10 is a vertical cross-sectional view of a mounted state of an electromagnetic contactor showing a conventional example.

11 is a cross-sectional view taken along the line XI-XI of FIG.

12 is an exploded perspective view showing a fixed iron core and a pressing spring in FIG. 11.

[Explanation of symbols]

 1 Main Frame 2 Electromagnetic Coil 3 Fixed Iron Core 4 Movable Iron Core 5 Contact Support 7 Movable Contact 10 Fixed Contact 14 Bottom Plate 18 Bottom Plate Support 21 Housing 22 Sliding Piece 23 Shock Absorbing Member 24 Vibration Absorbing Member 26 Cushioning Member

Claims (3)

[Claims] 1. An electromagnet for attracting a movable iron core to drive a movable contactor in a direction perpendicular to the attaching surface is provided in a main body frame having an opening on the attaching surface side, and a fixed iron core of the electromagnet is attached to the body frame. In the electromagnetic contactor attached to the bottom plate that closes the surface side opening, the bottom plate to which the fixed iron core is attached is held in the main body frame so as to be movable in the suction direction of the movable iron core, and the movable iron core is provided between the main body frame and the bottom plate. A shock absorbing device for an electromagnetic contactor, wherein a shock absorbing member for absorbing a shock during suction is inserted. 2. Engaging pieces parallel to the mounting surface of the body frame are formed on both sides of the bottom plate, and slide pieces having grooves formed corresponding to the engaging pieces are slidably accommodated in the housing. Further, bottom plate supports constituted by inserting buffer springs between the slide pieces and the housing are detachably attached to the mutually opposing side walls in the vicinity of the mounting surface of the main body frame from the outside. 2. A shock absorber for an electromagnetic contactor according to claim 1, wherein the engaging piece is held by a groove to hold the bottom plate. 3. A vibration absorbing member, a mass increasing member, or a cushioning member is attached to the back surface of the bottom plate.
Alternatively, the shock absorber of the electromagnetic contactor according to claim 2.