Contactor shell structure

Abstract

The utility model provides a contactor shell structure, a sealed inner cavity used for installing a contactor core body is arranged inside a shell, a fusible plug is arranged on the shell, and a contact switch controlled by the fusible plug is arranged on the inner wall of the shell. The contactor housing can timely exhaust and disconnect the driver circuit when the internal temperature of the contactor exceeds the design requirement, thereby guaranteeing the safety of the circuit.

Description

Technical Field

[0001] The utility model relates to the technical field of contactor manufacturing, and particularly relates to a contactor housing structure. Background Art

[0002] In an automatic control circuit, a contactor is equivalent to an automatic switch, which functions as safety protection and circuit switching in the circuit. A contactor usually consists of an external housing and an internal core. The core includes a driver and a contact switch composed of a moving contact and a static contact. The driver drives the moving contact to conduct or disconnect from the static contact according to a control signal to achieve the function of an automatic switch.

[0003] When a contactor is used in a high-voltage circuit, an arc will be generated at the moment of circuit on-off. The arc will generate open fire and high temperature, causing the metal inside the contactor to be ablated and oxidized. Therefore, a high-voltage contactor will completely seal the housing to isolate external oxygen. In addition, the metal plate for connecting the moving contact and the static contact will heat up under the working conditions of high voltage and large current. All the above heat generations will cause the air inside the contactor to expand. When the heat generation exceeds the design requirements, it may cause the melting and adhesion of the contact solder joints, resulting in the failure of the contactor and the inability to disconnect the circuit, or it may also cause the explosion of the contactor due to gas expansion. Summary of the Utility Model

[0004] Aiming at the defects of the background art, the utility model provides a contactor housing structure, which is provided with a contact switch controlled by a fusible plug, and can exhaust gas in time and disconnect the driver circuit when the temperature inside the contactor exceeds the design requirements.

[0005] The interior of the contactor housing has a sealed cavity for installing the contactor core. The housing is equipped with a fusible plug, and a contact switch controlled by the fusible plug is provided on the inner wall of the housing.

[0006] Preferably, the contact switch includes a first contact, a second contact, a third contact, a fourth contact and a conduction contact plate. The first contact and the second contact are used for electrically connecting with the electromagnetic coil in the contactor core. The second contact is electrically connected with the third contact. The third contact and the fourth contact are connected through the conduction contact plate.

[0007] The contactor housing structure further includes at least two external control lines. One external control line is electrically connected with the first contact, and the other external control line is electrically connected with the fourth contact.

[0008] The fusible plug includes a housing and a fusible core body. The conduction contact plate is fixedly connected to the bottom of the fusible core body.

[0009] Preferably, the conduction contact plate is connected to the fusible core body through an elastic bracket made of an insulating material.

[0010] The elastic support is provided with a spring piece, the bottom end of the spring piece is fixedly connected to the top of the elastic support, and the top end of the spring piece elastically abuts against the inner wall of the sealed inner cavity.

[0011] Preferably, one end of the elastic support connected to the fusible core is provided with a fork-shaped connector, the bottom of the fusible core is provided with a slot for installing the fork-shaped connector, and a limiting baffle is arranged in the middle of the fork-shaped connector.

[0012] Preferably, the material of the elastic support is ceramic.

[0013] Preferably, the housing includes a bottom cup and a top cover, the top cover is installed at the top cup mouth of the bottom cup, and the connection between the bottom cup and the top cover is sealed by a potting process.

[0014] Preferably, the bottom cup includes an inner cup liner and an outer cup cover, and a bottom cup potting gap communicating with the potting port provided on the top cover is left between the side walls of the cup liner and the cup cover.

[0015] Preferably, the top cover includes an inner cover and an outer sleeve ring, the height of the outer sleeve ring is higher than that of the inner cover, the inner cover covers the opening at the top of the cup liner, the outer sleeve ring is arranged around the inner cover, and the bottom of the outer sleeve ring is buckled on the top end of the cup cover;

[0016] The gap between the inner cover and the outer sleeve ring communicates with the bottom cup potting gap.

[0017] Preferably, the inner cover is suspended with a terminal fixing seat and a fusible plug fixing seat, and the terminal fixing seat and the fusible plug fixing seat are connected to the outer sleeve ring through a connecting plate.

[0018] Preferably, the housing is further provided with a nozzle.

[0019] The beneficial effects of the present utility model include:

[0020] 1. The contactor housing structure can exhaust gas in time and disconnect the driver circuit when the temperature inside the contactor exceeds the design requirements through the fusible plug and the contact switch controlled by the fusible plug, ensuring the safety of the circuit.

[0021] 2. The contact switch has a simple structure and is convenient for installation;

[0022] 3. The contactor housing structure has extremely strong airtightness and electromagnetic shielding ability. Description of the Drawings

[0023] The following will describe the present utility model in detail in conjunction with the embodiments and the drawings, where:

[0024] Figure 1 is a perspective view of the contactor housing of the present utility model.

[0025] Figure 2 is a perspective view of the contactor housing before potting of the present utility model.

[0026] Figure 3 It is an exploded view of the structure of the contactor housing of the present utility model.

[0027] Figure 4 It is a cross-sectional view of the contactor housing of the present utility model in the horizontal direction.

[0028] Figure 5 It is a cross-sectional view of the contactor housing of the present utility model in the longitudinal direction.

[0029] Figure 6 It is a structural diagram of the bottom surface of the top cover of the present utility model.

[0030] Figure 7 It is a longitudinal cross-sectional view of the fusible plug of the present utility model.

[0031] Figure 8 It is a schematic structural diagram of the elastic support and the conduction contact plate of the present utility model.

[0032] Reference numerals:

[0033] 1 - Sealed inner cavity, 2 - Fusible plug, 21 - Sleeve housing, 22 - Fusible core, 23 - Slot, 3 - Contact switch, 31 - First contact, 32 - Second contact, 33 - Third contact, 34 - Fourth contact, 4 - Conduction contact plate, 5 - External control line, 6 - Elastic support, 61 - Spring piece, 62 - Fork-shaped connector, 63 - Limit baffle, 7 - Bottom cup, 71 - Cup liner, 72 - Cup cover, 73 - Glue filling gap of the bottom cup, 8 - Top cover, 81 - Inner cover, 82 - Outer sleeve ring, 83 - Glue filling port, 91 - Terminal fixing seat, 92 - Fusible plug fixing seat, 93 - Terminal, 94 - Connecting plate, 95 - Air nozzle. Detailed implementation manners

[0034] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present utility model clearer and more understandable, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0035] Therefore, a feature pointed out in this specification will be used to illustrate one feature of one embodiment of the present utility model, rather than implying that each embodiment of the present utility model must have the feature described. In addition, it should be noted that this specification describes many features. Although some features may be combined together to show a possible system design, these features can also be used in other combinations not explicitly described. Therefore, unless otherwise stated, the described combination is not intended to be limiting.

[0036] The principle of the present utility model will be described in detail below with reference to the accompanying drawings and embodiments.

[0037] The present utility model proposes a contactor housing structure as shown in Figure 1-8 . The housing has a sealed inner cavity 1 for installing the contactor core. The housing is equipped with a fusible plug 2, and the inner wall of the housing is provided with a contact switch 3 controlled by the fusible plug 2, which can exhaust gas in time and disconnect the circuit when the internal temperature of the contactor exceeds the design requirements, ensuring the safety of the circuit.

[0038] The fusible plug 2 is cylindrical in shape, with a high-temperature-resistant outer shell 21 and a fusible core 22 made of fusible metal inside. The fusible metal can be a single metal or an alloy, and can include one or more of metals such as lead, tin, and indium. The contact switch 3 is used for the switch control of the driver in the core. That is, when the fusible core 22 melts, the contact switch 3 automatically closes, and after the driver loses power, the moving contact and the static contact are separated, closing the contactor circuit.

[0039] This embodiment can be used for contactors with electromagnetic coils as drivers. The contact switch 3 includes a first contact 31, a second contact 32, a third contact 33, a fourth contact 34, and a conduction contact plate 4. Among them, the first contact 31 and the second contact 32 are used for electrically connecting with the electromagnetic coil in the contactor core. The second contact 32 is electrically connected to the third contact 33. The third contact 33 and the fourth contact 34 are connected through the conduction contact plate 4, and the conduction contact plate 4 is fixedly connected to the bottom of the fusible core 22. The contactor housing structure also includes at least two external control lines 5, which are used to transmit control signals to the electromagnetic coil. One external control line 5 is electrically connected to the first contact 31, and the other external control line 5 is electrically connected to the fourth contact 34. Under normal circumstances, the conduction contact plate 4 keeps the third contact 33 and the fourth contact 34 in a conducting state. At this time, the electromagnetic coil works normally according to the control signal of the external control line 5. When the internal temperature of the contactor exceeds the design requirements, the fusible core 22 reaches the melting temperature and liquefies and deforms, so as to flow out of the outer shell 21, discharging the high-temperature gas expanded inside the housing to the outside of the housing. At the same time, the melted fusible core 22 can no longer support the conduction contact plate 4, so that the conduction contact plate 4 disengages from the third contact 33 and the fourth contact 34, forcibly disconnecting the power supply of the electromagnetic coil. After the magnetism of the electromagnetic coil disappears, the moving contact and the static contact are separated, finally closing the external circuit.

[0040] In this embodiment, the conduction contact plate 4 is connected to the fusible core 22 through an elastic support 6 made of a ceramic plate. The ceramic plate has good insulation, which can avoid attracting electric arcs to burn the fusible core 22. In addition, the ceramic plate has poor thermal conductivity. The melting point of the fusible core 22 is modulated according to the temperature of the air inside the housing. The ceramic plate is in direct contact with the fusible core 22, and the poor thermal conductivity can avoid the fusible core 22 being affected by temperature interference and melting in advance.

[0041] The housing includes a bottom cup 7 and a top cover 8, and the top cover 8 is installed at the top cup opening of the bottom cup 7. The elastic support 6 is provided with a spring piece 61. The bottom end of the spring piece 61 is fixedly connected to the top of the elastic support 6, and the top end of the spring piece 61 elastically abuts against the bottom surface of the top cover 8. After the fusible core 22 melts, the spring piece 61 will force the conduction plate 4 to separate from the third contact 33 and the fourth contact 34, which can prevent the third contact 33 and the fourth contact 34 from being welded together and causing forced welding with the conduction plate 4.

[0042] In this embodiment, one end of the elastic support 6 connected to the fusible core 22 is provided with a fork-shaped connector 62. The bottom of the fusible core 22 is provided with a slot 23 for installing the fork-shaped connector 62, and a limiting baffle 63 is provided in the middle of the fork-shaped connector 62. During installation, after pressing the spring piece 61 upward against the bottom of the top cover 8, insert the end of the elastic support 6 with the fork-shaped connector 62 into the slot 23, and then rotate the elastic support 6 until the conduction plate 4 is in full contact with the third contact 33 and the fourth contact 34.

[0043] In this embodiment, the bottom cup 7 includes an inner iron cup liner 71 and an outer cup cover 72. There is a bottom cup potting gap 73 between the side walls of the cup liner 71 and the cup cover 72, which is communicated with the potting port 83 provided on the top cover 8. The top cover 8 includes an inner cover 81 and an outer sleeve ring 82. The height of the outer sleeve ring 82 is higher than that of the inner cover 81. The inner cover 81 covers the opening at the top of the cup liner 71, and the outer sleeve ring 82 is provided on the periphery of the inner cover 81. The bottom of the outer sleeve ring 82 is buckled on the top end of the cup cover 72; the gap between the inner cover 81 and the outer sleeve ring 82 is communicated with the bottom cup potting gap 73. The top of the top cover 8 is the potting port 83. Inject the epoxy resin glue into the outer sleeve ring 82, and the glue will enter the bottom cup potting gap 73 and fill the space inside the outer sleeve ring 82, completely sealing the connection between the bottom cup 7 and the top cover 8 through the glue, and bonding the entire housing into a whole, improving the sealing performance and structural strength of the contactor housing structure.

[0044] In this embodiment, the inner cover 81 is suspended with a terminal fixing seat 91 and a fusible plug fixing seat 92. The terminal fixing seat 91 and the fusible plug fixing seat 92 are connected to the outer sleeve ring 82 through a connecting plate 94. There are two terminal fixing seats 91 for installing terminals 93. The terminals 93 are used to connect external circuits, and the bottom ends of the terminals 93 are electrically connected to the static contacts. The terminal fixing seat 91 facilitates the installation and fixation of the terminals 93, and the fusible plug fixing seat 92 facilitates the installation and fixation of the fusible plug 2. At the same time, they also act as reinforcing ribs in the potted glue, preventing the glue area from being too large and easily cracking when being impacted. In addition, the glue will also seal the gaps between the parts where the terminals 93 and the fusible plug 2 pass through the inner cover 81 and the inner cover 81.

[0045] In this embodiment, the housing is further provided with a nozzle 95, which is used to extract the gas in the sealed inner cavity 1 during the production of the contactor, or inject an anti-oxidation gas, such as nitrogen, into the sealed inner cavity 1. The nozzle 95 is also installed on the inner cover 81, and the gap between the part of the nozzle 95 passing through the inner cover 81 and the inner cover 81 is also sealed with a colloid to ensure the airtightness of the contactor housing.

[0046] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A contactor housing structure, the interior of the housing having a sealed cavity for mounting a contactor core body, characterized in that, The housing is equipped with a fusible plug, and the inner wall of the housing is provided with a contact switch controlled by the fusible plug.

2. The contactor housing structure according to claim 1, characterized in that, The contact switch includes a first contact, a second contact, a third contact, a fourth contact, and a conduction contact plate. The first contact and the second contact are used for electrically connecting with the electromagnetic coil in the contactor core. The second contact is electrically connected to the third contact, and the third contact and the fourth contact are connected through the conduction contact plate. The contactor housing structure further includes at least two external control lines. One external control line is electrically connected to the first contact, and the other external control line is electrically connected to the fourth contact. The fusible plug includes a housing and a fusible core body. The conduction contact plate is fixedly connected to the bottom of the fusible core body.

3. The contactor housing structure according to claim 2, wherein, The conduction contact plate is connected to the fusible core body through an elastic bracket made of an insulating material. The elastic bracket is provided with a spring piece. The bottom end of the spring piece is fixedly connected to the top of the elastic bracket, and the top end of the spring piece elastically abuts against the inner wall of the sealed inner cavity.

4. The contactor housing structure according to claim 3, characterized in that, One end of the elastic bracket connected to the fusible core body is provided with a fork-shaped connector. The bottom of the fusible core body is provided with a slot for installing the fork-shaped connector, and a limiting baffle is arranged in the middle of the fork-shaped connector.

5. The contactor housing structure according to claim 3, wherein The material of the elastic bracket is ceramic.

6. The contactor housing structure according to claim 2, characterized in that, The housing includes a bottom cup and a top cover. The top cover is installed at the top cup mouth of the bottom cup, and the connection between the bottom cup and the top cover is sealed by a potting process.

7. The contactor housing structure according to claim 6, wherein, The bottom cup includes an iron cup liner inside and a cup cover outside. A bottom cup potting gap communicating with the potting port provided on the top cover is left between the side walls of the cup liner and the cup cover.

8. The contactor housing structure according to claim 7, wherein, The top cover includes an inner cover and an outer sleeve ring. The height of the outer sleeve ring is higher than that of the inner cover. The inner cover covers the opening at the top of the cup liner, the outer sleeve ring is arranged around the inner cover, and the bottom of the outer sleeve ring is buckled on the top end of the cup cover. The gap between the inner cover and the outer sleeve ring communicates with the bottom cup potting gap.

9. The contactor housing structure according to claim 8, wherein, The inner cover is suspended with a terminal fixing seat and a fusible plug fixing seat. The terminal fixing seat and the fusible plug fixing seat are connected to the outer sleeve ring through a connecting plate.

10. The contactor housing structure according to claim 1, wherein, The housing is also provided with a nozzle.

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