Explosion-proof electric appliance box assembly of R290 heat pump

Abstract

The utility model discloses an explosion-proof electric appliance box assembly of an R290 heat pump. The explosion-proof electric appliance box assembly comprises an electric appliance box, a junction box and a sealed connecting pipe, the electric appliance box comprises a box base, a box cover and sealing cotton, the box base is a box body with an opening in the upper end and a concave cavity in the middle, and the concave cavity is provided with a printed circuit board; the edge of the upper end of the box base is provided with a horizontally-arranged turned-over edge, and the turned-over edge is provided with a screw installation hole. The sealing cotton is adhered to the bottom of the box cover, the box cover is fixedly connected with the box seat through screws, and the sealing cotton is tightly pressed on the turned-over edge of the box seat; the inner and outer ends of the sealed connecting pipe are respectively connected with the electric appliance box and the junction box. The R290 heat pump explosion-proof electric appliance box assembly is simple and reasonable in structural design, air tightness in the box is guaranteed, refrigerants can be effectively prevented from entering the electric appliance box, and the risk of combustion explosion caused by the fact that a circuit board makes contact with the leaked refrigerants due to ignition or combustion under abnormal conditions is prevented; explosion-proof rectification is carried out on a structure sealing mode, a wiring mode and a wiring connection mode.

Description

Technical Field

[0001] This utility model relates to the field of heat pump accessories technology, and in particular to an explosion-proof electrical box assembly for an R290 heat pump. Background Technology

[0002] R-290 refrigerant, also known as R290, is propane (chemical formula C3H8). R290 is a hydrocarbon refrigerant that does not damage the ozone layer and has a very low greenhouse effect, making it one of the most environmentally friendly refrigerants available today. An R290 heat pump is a heat pump that uses R290 as its refrigerant.

[0003] Current heat pump refrigerants are trending towards those with low Global Warming Potential (GWP). R290, in particular, boasts excellent GWP and low-temperature performance, but it is also flammable and explosive. Traditional heat pump units have historically used refrigerants with relatively good safety performance, and heat pump manufacturers have limited experience with flammable and explosive refrigerants. Therefore, R290 heat pumps are not suitable for conventional heat pump electrical boxes.

[0004] This application discloses an explosion-proof electrical box assembly for an R290 heat pump, which is specifically optimized in terms of structure to improve the explosion-proof performance of the heat pump unit and adapt to the safe operation of the R290 heat pump. Utility Model Content

[0005] The purpose of this utility model is to provide an explosion-proof electrical box assembly for an R290 heat pump. Its structural design is simple and reasonable, ensuring the airtightness of the box and effectively preventing refrigerant from entering the electrical box. This prevents the circuit board from coming into contact with leaked refrigerant due to arcing or combustion under abnormal conditions, which could lead to combustion and explosion. Addressing the issue that the wiring layout and sealing of common heat pump electrical boxes do not meet the explosion-proof requirements for the flammable and explosive refrigerant R290, explosion-proof modifications have been made to the structural sealing method, wiring method, and wire connection method.

[0006] To solve the above-mentioned technical problems, the technical solution of this utility model is as follows:

[0007] An explosion-proof electrical box assembly for an R290 heat pump includes an electrical box, a junction box, and a sealed connecting pipe;

[0008] The electrical box includes a box base, a box cover, and sealing cotton. The box base is a box body with an opening at the top and a recessed cavity in the middle. The recessed cavity is equipped with a printed circuit board.

[0009] The upper edge of the box base has a horizontally set flange (sheet metal bend), and the flange has screw mounting holes; the sealing cotton is adhered to the bottom of the box cover, and the box cover is fixedly connected to the box base by screws or other fasteners, which press the sealing cotton tightly onto the flange of the box base. The compression of the sealing cotton creates a sealing band, thereby achieving gas sealing at the top of the electrical box. Preferably, the sealing cotton is IXPE cotton.

[0010] The sealed connecting pipe is connected to an electrical box and a junction box at its inner and outer ends, respectively.

[0011] The junction box is where the terminal block of the heat pump unit (unit) is installed. It mainly facilitates the user to connect the power cord to the unit. Because high voltage has a high risk of arcing, the junction box is also sealed. The junction box is connected to the electrical box by a sealed connecting pipe, so that the power cord of the junction box can be connected to the electrical box to supply power to the printed circuit board. The low voltage control output line on the printed circuit board can be connected to the junction box terminal through the pipe, which is convenient for the user to install externally.

[0012] Because refrigerant may leak in the compressor cavity, in order to prevent refrigerant from leaking into the electrical box, an L-shaped fence is set behind the cross membrane of the electrical box, and explosion-proof mud is filled in the fence for sealing, sealing the gap between the wire harness and the cross membrane (6), and preventing refrigerant gas from flowing into the electrical box from the compressor cavity.

[0013] The beneficial effects of this utility model are:

[0014] Its structural design is simple and reasonable, ensuring the airtightness of the box and effectively preventing refrigerant from entering the electrical box, thus avoiding the risk of refrigerant combustion in the electrical box;

[0015] In response to the fact that the wiring layout and sealing of common heat pump electrical boxes do not meet the explosion-proof measures required for R290 flammable and explosive refrigerants, explosion-proof modifications were made to the main strong and weak current installation points, namely the electrical boxes, in terms of structural sealing methods, wiring methods, and wiring connection methods. Attached Figure Description

[0016] Figure 1 This is a structural schematic diagram of an explosion-proof electrical box assembly for an R290 heat pump according to the present invention;

[0017] Figure 2 This is a bottom view of an explosion-proof electrical box assembly for an R290 heat pump according to this utility model.

[0018] Figure 3 This is a side view of an explosion-proof electrical box assembly for an R290 heat pump according to this utility model. Detailed Implementation

[0019] The following further describes specific embodiments of the present invention in conjunction with the accompanying drawings. It should be noted that the descriptions of these embodiments are intended to aid understanding of the present invention and do not constitute limitations on the present invention. Furthermore, the technical features involved in the various embodiments of the present invention described below may be combined with one another as long as they do not conflict with one another.

[0020] like Figure 1-Figure 3 As shown, an explosion-proof electrical box assembly for an R290 heat pump includes an electrical box 1, a junction box 2, and a sealed connecting pipe 3.

[0021] The electrical box 1 includes a box base 11, a box cover 12, and a sealing cotton 13. The box base 11 is a box body with an opening at the top and a recess 14 in the middle. The recess 14 is provided with a printed circuit board.

[0022] The upper edge of the box base 11 is provided with a horizontally arranged flange 111 (sheet metal bending), and the flange 111 has screw mounting holes; the sealing cotton 13 is adhered to the bottom of the box cover 12, and the box cover 12 is fixedly connected to the box base 11 by screws or other fasteners, which press the sealing cotton 13 tightly onto the flange 111 of the box base 11. The compression of the sealing cotton 13 creates a sealing strip, thereby achieving gas sealing at the top of the electrical box 1. Preferably, the sealing cotton 13 is IXPE cotton.

[0023] The sealed connecting pipe 3 is connected to the electrical box 1 and the junction box 2 at its inner and outer ends, respectively.

[0024] Junction box 2 is the location where the terminal block of the heat pump unit (unit) is installed. It is mainly to facilitate the user to install and connect the power cord of the unit. Due to the high risk of arcing from high voltage, junction box 2 is also sealed. A sealed connecting pipe 3 connects junction box 2 to electrical box 1, allowing the power cord of junction box 2 to be connected to the printed circuit board inside electrical box 1 to supply power. The low voltage control output line on the printed circuit board can be connected to the terminal of junction box 2 through the sealed connecting pipe 3, which facilitates external installation.

[0025] The electrical box 1 is located above the fan chamber 41 and compressor chamber 42 of the unit 4 (for easy connection with strong and weak power lines), and the junction box 2 is located on the outside of the frame of the unit 4.

[0026] Because refrigerant may leak inside the compressor cavity 42, a cross-shaped rubber diaphragm hole 15 is provided on one side of the electrical box 1. The cross-shaped rubber diaphragm hole 15 is a through hole with a cross-shaped opening groove. The wires enter the compressor cavity 42 through the cross-shaped rubber diaphragm hole 15 of the electrical box 1. To prevent refrigerant from leaking into the electrical box 1, an L-shaped enclosure 16 is installed after the cross-shaped rubber diaphragm hole 15 of the electrical box 1. Explosion-proof mud 17 is filled into the enclosure 16 for sealing, blocking the gap between the wire harness and the cross-shaped rubber diaphragm hole 15, and preventing refrigerant gas from flowing into the electrical box 1 from inside the compressor cavity 42.

[0027] The high-voltage wiring harness is connected to the fan cavity 41 via the PG connector 18 of the electrical box 1. Since the fan cavity 41 is connected to the external environment, the refrigerant concentration is relatively lower than that of the compressor cavity 42, and the corresponding explosion-proof requirements are lower than those of the compressor cavity. After the high-voltage wiring harness is connected to the electrical box 1 via the PG connector 18, tightening the PG connector 18 can achieve the condition of locking and sealing the wiring harness.

[0028] The embodiments of this utility model have been described in detail above with reference to the accompanying drawings, but this utility model is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions, and alterations to these embodiments without departing from the principles and spirit of this utility model will still fall within the protection scope of this utility model.

Claims

1. An explosion-proof electrical box assembly for an R290 heat pump, characterized in that: Includes electrical boxes, junction boxes, and sealed connecting pipes; The electrical box includes a box base, a box cover, and sealing cotton. The box base is a box body with an opening at the top and a recessed cavity in the middle. The recessed cavity is equipped with a printed circuit board. The upper edge of the box base has a horizontally arranged flange with screw mounting holes; the sealing cotton is adhered to the bottom of the box cover, and the box cover is fixedly connected to the box base by screws, pressing the sealing cotton tightly against the flange of the box base. The sealed connecting pipe is connected to an electrical box and a junction box at its inner and outer ends, respectively.

2. The explosion-proof electrical box assembly of the R290 heat pump according to claim 1, characterized in that: It also includes heat pump units, which include a fan chamber, a compressor chamber, and a frame; The electrical box is located above the fan chamber and compressor chamber of the heat pump unit; the junction box is located on the outside of the frame of the heat pump unit.

3. The explosion-proof electrical box assembly of the R290 heat pump according to claim 2, characterized in that: The electrical box has a cross-shaped rubber membrane hole on one side, which is a through hole with a cross-shaped opening groove. The wires are connected to the printed circuit board through the cross-shaped rubber membrane hole. An L-shaped fence is set behind the cross-shaped rubber membrane hole of the electrical box. The fence is filled with explosion-proof mud for sealing, blocking the gap between the wire harness and the cross-shaped membrane.

4. The explosion-proof electrical box assembly of the R290 heat pump according to any one of claims 1-3, characterized in that: The sealing cotton is IXPE cotton.

5. The explosion-proof electrical box assembly of the R290 heat pump according to claim 3, characterized in that: The electrical box is also equipped with a PG connector on one side. The cable enters the fan cavity through the PG connector of the electrical box and connects with the electrical components.

Images