Patent Application
20230420206
This application claims the benefit of Chinese Patent Application No. CN202210752236.5 filed on Jun. 28, 2022, in the State Intellectual Property Office of China, the whole disclosure of which is incorporated herein by reference.
The present invention relates to an electromagnetic relay, in particular to an electromagnetic relay for multiphase circuits.
An electromagnetic relay for multiphase circuits typically includes a housing, an insulator, multiple electric arc isolation plates, multiple movable terminals, and multiple static terminals. The insulator is installed in the housing and includes an inner cavity formed therein. The plurality of electric arc isolation plates are installed in the insulator to divide the inner cavity of the insulator into a plurality of chambers. The movable terminal and the static terminal are installed in each chamber. However, in these devices, the arc separation plate occupies space in the chamber, resulting in a reduction in the opening distance between the movable contact of the movable terminal and the static contact of the static terminal, which is prone to arcing erosion. In addition, the manufacture of electric arc isolation plates requires the use of separate molds, which can lead to increased costs and complex assembly of electric arc isolation plates.
In addition, each movable terminal of the relay includes a fixed terminal and a U-shaped movable elastic piece. The fixed terminal is fixed to the insulator and cannot be moved. The movable elastic piece comprises a fixed end fixed to the fixed terminal and a cantilever portion extending from the fixed end. The cantilever portion of the movable elastic piece faces the body portion of the fixed terminal. When a short circuit current passes through the cantilever portion of the movable elastic piece and the body portion of the fixed terminal, the current directions on the fixed terminal and the movable elastic piece are opposite, which generates electrical force between the fixed terminal and the movable elastic piece. When a short circuit current passes through a closed movable contact, a strong current contraction produces a large Holm force that drives the movable contact to separate from the static contact. The direction of the electric force generated by the aforementioned opposite currents and the elastic force of the armature connection spring piece is the same but opposite to the Holm force to resist the Holm force together. This prevents the closed movable contact from springing back and breaking from the static contact. However, in prior art devices, the spacing between the movable elastic piece of the U-shaped structure and the fixed terminal is relatively large, and the effective length of the movable elastic piece of the U-shaped structure is relatively small, which can lead to relatively small electrical force generated and insufficient resistance to the Holm force. This creates a risk of rebound and disconnection of the movable contact.
According to an embodiment of the present disclosure, an electromagnetic relay includes a housing, an insulator, a plurality of static terminals, and a plurality of movable terminals. The housing has a top wall and a bottom opening that are opposite in a height direction, a front sidewall and a rear sidewall that are opposite in a front and rear direction, and a left sidewall and a right sidewall that are opposite in a left-right direction. The insulator is arranged in the housing and formed is with a plurality of chambers which are opened towards the front sidewall of the housing and are arranged in a row along the left-right direction. The insulator includes a partition plate located between two adjacent chambers. The plurality of static terminals are fixedly arranged in respective ones of the plurality of chambers of the insulator. The plurality of movable terminals are arranged in respective ones of the plurality of chambers and are adapted for electrical contact with the plurality of static terminals.
The invention will now be described by way of example with reference to the accompanying Figures, of which:
Exemplary embodiments of the present disclosure will be described hereinafter in detail with reference to the attached drawings, wherein the like reference numerals refer to the like elements. The present disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiment set forth herein; rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the concept of the disclosure to those skilled in the art.
In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.
According to an embodiment of the present invention, an electromagnetic relay includes a housing having a top wall and a bottom opening that are opposite in a height direction, a front sidewall and a rear sidewall that are opposite in a front and rear direction, and a left sidewall and a right sidewall that are opposite in a left-right direction. The relay further includes an insulator housed in the housing and formed with a plurality of chambers which are opened towards the front sidewall of the housing and are arranged in a row along the left-right direction. A plurality of static terminals are fixedly installed in the plurality of chambers of the insulator, and a plurality of movable terminals are respectively installed in the plurality of chambers for electrical contact with the plurality of static terminals. The insulator has a partition plate located between two adjacent chambers, and a rib is formed on the inner wall surface of the front sidewall of the housing. The front side of the partition plate is positioned against the inner wall surface of the front sidewall of the housing, and a side of the rib is positioned against the left or right side of the partition plate to electrically isolate the adjacent two chambers from each other.
As shown in
The insulator 20 has a partition plate 23 located between two adjacent chambers 201. A rib 111 is formed on the inner wall surface of the front sidewall 11 of the housing 10. The front side of the partition plate 23 is arranged against the inner wall surface of the front sidewall 11 of the housing 10, and the side surface of the rib 111 is arranged against the left or right side surface of the partition plate 23 to electrically isolate the two adjacent chambers 201 from each other. In the illustrated embodiment, the side surface of the rib 111 abuts against the left side surface of the partition plate 23.
As shown in
In the illustrated embodiment, the insulator 20 has a bottom plate 21, a top plate 22, a left side plate, a right side plate, and a rear side plate 24 that surround the inner cavity. The partition plate 23 divides the inner cavity of the insulator 20 into the plurality of chambers 201. The rear side of the fixed terminal 31 is against the rear side plate 24 of the insulator 20, so that the fixed terminal 31 is fixed between the rib 111 and the rear side plate 24 in the front-rear direction. The lower portion of the rear side plate 24 of the insulator 20 is opened, and the outer side of the rear side plate 24 is arranged against the inner wall surface of the rear sidewall 12 of the housing 10 to electrically isolate the adjacent two chambers 201 from each other.
The static terminal 4 includes a terminal body 42 and a static contact 43. The terminal body 42 is fixed to the insulator 20. The static contact 43 is fixed to one end of the terminal body 42 and faces the movable contact 33. The movable elastic piece 32 is adapted to be moved between the closed position and the opened position. As shown in
The insulator 20 has a fixed portion 231 located in the chamber 201. The fixed portion 231 is positioned opposite to the free end of the cantilever portion 320 of the movable elastic piece 32. The terminal body 42 of the static terminal 4 is fixed to the fixed portion 231 of the insulator 20.
Still referring to
The cantilever portion 320 of the movable elastic piece 32 has at least one bending or bent portion 323 to increase the elasticity of the cantilever portion 320 of the movable elastic piece 32 and reduce the spacing between the cantilever portion 320 of the movable elastic piece 32 and the main body 310 of the fixed terminal 31. In addition, the bending portion 323 can also increase the total length of the cantilever portion 320 of the movable elastic piece 32, thereby increasing the effective length of the movable elastic piece 32. As the spacing between the cantilever portion 320 of the movable elastic piece 32 and the main body 310 of the fixed terminal 31 decreases, and the effective length of the movable elastic piece 32 increases. This arrangement increases the electrical force generated by the opposite currents between the movable elastic piece 32 and the fixed terminal 31, thereby more reliably ensuring that the movable contact 33 does not rebound and open when in the closed position. In the illustrated embodiment, the bent portion 323 is in an arc shape protruding toward the main body 310 of the fixed terminal 31. The movable terminal 3 includes a plurality of movable elastic pieces 32′ and 32″ stacked together.
The movable elastic piece 32 includes a first movable elastic piece 32′ and a second movable elastic piece 32″ stacked together. The fixed ends 321′ and 321″ of the first and second movable elastic pieces 32′ and 32″ are fixed to the fixed terminal 31. The free ends of the first and second movable elastic pieces 32′ and 32′ are fixed together by the movable contact 33.
The first movable elastic piece 32′ is closer to the main body 310 of the fixed terminal 31 than the second movable elastic piece 32′. The bending portions 321′ and 321″ of the first and second movable elastic pieces 32′ and 32″ are in an arc shape protruding toward the main body 310 of the fixed terminal 31. The radius of the bending portion 321′ of the first movable elastic piece 32′ is larger than that of the bending portion 321″ of the second movable elastic piece 32″. The bending portion 321″ of the second movable elastic piece 32″ is accommodated in the bending portion 321′ of the first movable elastic piece 32′.
The fixed end 321 of the movable elastic piece 32 can be riveted or welded to the upper end of the fixed terminal 31. The movable contact 33 can be riveted or welded to the free end of the movable elastic piece 32 and protrude towards the static contact 43 of the static terminal 4. The static contact 43 of the static terminal 4 can be riveted or welded to one end of the terminal body 42 of the static terminal 4.
In the exemplary embodiment, the lower ends 313 and 423 of the main body 310 of the fixed terminal 31 and the terminal body 42 of the static terminal 4 pass through the bottom plate 21 of the insulator 20 and are exposed through the bottom opening of the housing 10 to be electrically connected to an external circuit (not shown).
As shown in
As shown, when the coil 50 is energized, the armature 54 is moved to the termination position under the action of electromagnetic force to simultaneously drive multiple movable elastic pieces 32 to the closed position through the push member 60. When the coil 50 deenergized, the electromagnetic force disappears, and the armature 54 is rotated to the initial position under the elastic restoring force of the connection spring piece 55 to simultaneously drive multiple movable elastic pieces 32 to the opened position through the push member 60.
The push member 60 includes a push rod 61 that is movably mounted on the insulator 20. The push member further includes a plurality of push portions 63 which are connected to the push rod 61 and are respectively formed with slots that allow the movable elastic pieces 32 to pass through. A connecting portion 62 of the push member 60 is located at one end of the push rod 61 and is rotationally connected to the armature 54.
As shown in
In addition, those areas in which it is believed that those of ordinary skill in the art are familiar, have not been described herein in order not to unnecessarily obscure the invention described. Accordingly, it has to be understood that the invention is not to be limited by the specific illustrative embodiments, but only by the scope of the appended claims.
It should be appreciated for those skilled in this art that the above embodiments are intended to be illustrated, and not restrictive. For example, many modifications may be made to the above embodiments by those skilled in this art, and various features described in different embodiments may be freely combined with each other without conflicting in configuration or principle.
Although several exemplary embodiments have been shown and described, it would be appreciated by those skilled in the art that various changes or modifications may be made in these embodiments without departing from the principles and spirit of the disclosure, the scope of which is defined in the claims and their equivalents.
As used herein, an element recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural of the elements or steps, unless such exclusion is explicitly stated. Furthermore, references to “one embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments “comprising” or “having” an element or a plurality of elements having a particular property may include additional such elements not having that property.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202210752236.5 | Jun 2022 | CN | national |
