High-voltage direct-current inverter wire harness assembly of transportation refrigeration equipment

Abstract

The invention provides a transportation refrigeration equipment high-voltage direct current inverter wire harness assembly, which comprises a wire harness and a connector, the connector comprises a butt joint electric connection part and a connection fastening part, the butt joint electric connection part and the connection fastening part are clamped through a buckle, and the butt joint electric connection part and the connection fastening part are connected through the buckle. The edge of a wire inlet at the bottom of the connection fastening part extends outwards at equal intervals in a transition mode to form a circle of multiple independent arc-shaped surrounding elastic pieces, the wire harness penetrates into the connection fastening part from the middle of the surrounding elastic pieces and is connected with the butt joint electric connection part through wiring terminals, and the outer circles of the surrounding elastic pieces are fastened through binding band hoops. According to the assembly, through structure optimization, the connection reliability, the sealing performance and the mechanical durability of the wire assembly under the severe working conditions of vibration, temperature, humidity, oil contamination and the like are comprehensively improved.

Description

Technical Field

[0001] This invention relates to the field of automotive wiring harness technology, and more particularly to a high-voltage DC inverter wiring harness assembly for transportation refrigeration equipment. Background Technology

[0002] In cold chain transportation, the high-voltage DC inverter, as the core of power conversion for refrigeration equipment, directly determines the operational efficiency of the entire system. However, this connecting cable assembly operates in extreme environments characterized by continuous vibration, drastic temperature changes, and high levels of oil and moisture, and is under high-voltage conditions for extended periods. This amplifies systemic defects in existing technologies, such as insufficient mechanical connection reliability. Traditional connection and fixing methods are prone to loosening and poor contact under long-term vehicle vibration, potentially leading to high-voltage discharge and serious safety hazards. Furthermore, inadequate environmental tolerance and sealing capabilities, with imperfect sealing at connection interfaces and cable inlets, allow moisture and dust to intrude, easily causing electrochemical corrosion and insulation degradation, leading to high-voltage breakdown or short circuits. Additionally, the lack of effective external mechanical protection structures makes the outer sheath of the wiring harness susceptible to damage from friction and impact, resulting in connection failures and insulation hazards, affecting the reliability of the refrigeration system and the lifespan of components. These intertwined defects collectively constitute a bottleneck restricting the reliability, safety, and lifespan of transportation refrigeration equipment. Summary of the Invention

[0003] In view of the above, the present invention provides a high-voltage DC inverter wiring harness assembly for transportation refrigeration equipment. Through structural optimization, the connection reliability, sealing performance and mechanical durability of the wiring harness assembly are comprehensively improved under harsh working conditions such as vibration, temperature, humidity and oil contamination.

[0004] The present invention specifically adopts the following technical solution: a high-voltage DC inverter wiring harness assembly for transport refrigeration equipment, comprising a wiring harness and a connector. The connector includes a docking connection part and a connection fastening part, which are connected by a snap-fit. A plurality of independent arc-shaped circumferential spring pieces extend outward from the bottom inlet edge of the connection fastening part at equal intervals. The wiring harness passes through the middle of the circumferential spring pieces into the connection fastening part and is connected to the docking connection part through a terminal block. The outer ring of the circumferential spring pieces is fastened by a cable tie.

[0005] As a further improved technical solution, a protrusion is provided at the bottom of the outer wall of each of the circumferential spring pieces, and the cable tie is secured above the protrusion.

[0006] As a further improved technical solution, one end of the connecting fastener connected to the docking electrical connection part is an open cavity, and the end of the docking electrical connection part with a buckle is inserted into the cavity.

[0007] As a further improved technical solution, at least one sealing ring is provided on the inner wall of the cavity.

[0008] As a further improved technical solution, a bayonet is provided on the inner cavity sidewall of the connecting fastener, and the bayonet engages with the buckle on the sidewall of the docking electrical connection part.

[0009] As a further improved technical solution, a sealing gasket is provided inside the bottom inlet of the connection fastener, and the wire harness passes through the sealing gasket to form a seal at the connection.

[0010] As a further improved technical solution, the wire harness includes a conductor and a sequentially wrapped main insulation layer, inner sheath, and outer sheath. A corrugated tube is provided outside the wire harness. The conductor is formed by binding together multiple tin-plated soft copper wires after annealing. The main insulation layer is formed by extrusion of cross-linked polyolefin or silicone rubber material. The inner sheath is formed by extrusion of low-smoke halogen-free flame-retardant TPU material. The outer sheath is made of low-smoke halogen-free flame-retardant oil-resistant and wear-resistant TPU or polyether-type TPE material.

[0011] As a further improved technical solution, the corrugated pipe is slidably sleeved outside the outer sheath, and a limiting structure is provided at both ends of its axial sliding stroke. The limiting structure fixes both ends of the corrugated pipe to the wire harness to prevent the corrugated pipe from coming out.

[0012] As a further improved technical solution, the limiting structure is a rubber sleeve and a cable tie. The rubber sleeve is fitted onto the end of the corrugated pipe and has a through strip-shaped tightening opening along the axial direction. The cable tie is wrapped around the outer wall of the rubber sleeve.

[0013] As a further improved technical solution, the terminal is a circular terminal, the terminal is crimped and fixed to the conductor, and a heat shrink tubing is sleeved at the crimping point between the terminal and the conductor.

[0014] The high-voltage DC inverter wiring harness assembly for transportation refrigeration equipment of this invention employs a snap-fit ​​connector and a ring-shaped elastic cable tie with anti-slip protrusions for fixation, forming a dual anti-vibration locking system. This eliminates connection loosening and poor contact caused by vibration at the source, ensuring the long-term stability and safety of high-voltage electrical connections. A multi-layered sealing system is constructed, consisting of a connector interface sealing ring, a cable inlet sealing gasket, and adhesive heat shrink tubing at the crimping point. This achieves comprehensive airtight and watertight protection for the internal space of the connector, effectively resisting the intrusion of dust, moisture, and oil, and preventing insulation failure caused by contamination and corrosion. Furthermore, a sliding corrugated tube combined with a rubber sleeve tightening limit structure is introduced. On the one hand, this provides the high-voltage wiring harness with comprehensive and uninterrupted rigid protection against mechanical impact, scratches, and high-temperature oil contamination, overcoming the defect of easy damage to the wiring harness in the unprotected state. On the other hand, its unique limit design completely solves the persistent problem of traditional corrugated tubes easily coming loose and shifting, ensuring continuous and reliable protection, forming a complete "dynamic-static" combined protection system. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall wiring harness assembly of the high-voltage DC inverter for the transport refrigeration equipment in this application.

[0016] Figure 2 This is a schematic diagram of the connector in this application.

[0017] Figure 3 This is an exploded view of the connector in this application.

[0018] Figure 4 This is a schematic diagram of the rubber sleeve structure of this application. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0020] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connection," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0021] The high-voltage DC inverter wiring harness assembly for the transport refrigeration equipment in this embodiment is suitable for a high voltage range of 400V~1500VD and mainly consists of three parts: connector 100, wiring harness 200, and corrugated pipe 300.

[0022] The connector 100 includes a mating electrical connection part 110 and a connecting fastening part 120, both injection molded from flame-retardant PA66. One end of the connecting fastening part 120 is an open cavity 121, with an annular groove on the inner wall for mounting a sealing ring 122, and a bayonet 123 on the side wall. One end of the mating electrical connection part 110 has a latch 111 that engages with the bayonet 123. During assembly, the mating electrical connection part 110 is inserted into the cavity 121 until the latch 111 engages with the bayonet 123, producing a "click" sound. Simultaneously, the sealing ring 122 is compressed, achieving connection and sealing.

[0023] At the bottom edge of the cable inlet of the fastening part 120, an independent arc-shaped retaining spring extends outward at equal intervals, preferably four equally spaced arc-shaped retaining springs 124. The outer ring of the retaining spring is fastened by a cable tie, achieving initial fixation of the wire harness. Furthermore, a protrusion 1241 is provided at the bottom of the outer wall of each retaining spring, and the cable tie 400 is secured above the protrusion 1241 to prevent the cable tie from slipping out in a vibration environment, improving the reliability of the fixation. A rubber sealing gasket 126 is installed on the inside of the cable inlet, and the wire harness forms a secondary seal after passing through the sealing gasket, achieving double protection.

[0024] The wire harness 200 passes through the sealing gasket 126 from the center of the circumferential spring 124 and enters the interior of the connection fastening part 120. The ends of the conductors 201 at both ends of the wire harness 200 are crimped with circular terminals 210, one of which connects to a conductive sheet inside the mating electrical connection part 110. Adhesive-coated heat shrink tubing 211 is fitted over the crimped joint and heated to shrink and seal it. Then, nylon cable ties 400 are tightly fastened to the outer ring of the circumferential spring 124, ensuring that the cable ties 400 are positioned above all the protrusions 125. After the cable ties 400 are tightened, the circumferential spring 124 deforms inward, firmly gripping the outer sheath of the wire harness 200.

[0025] The wire harness 200 includes conductor 201 and sequentially wrapped main insulation layer, inner sheath, and outer sheath. Conductor 201 is made of T2 copper wire, which is formed by annealing multiple fine-diameter pure copper wires (to eliminate internal stress) and then bundling them together at an optimized pitch using a wire bundling machine. This structure forms a highly flexible conductor core, whose performance meets the requirements of Class 5 (soft conductor) or Class 6 (extra-soft conductor) in GB / T 3956 standard. It is resistant to bending fatigue, and T2 copper ensures excellent conductivity and mechanical stability within an operating temperature range of -40℃ to 105℃. The main insulation layer is formed on the outside of the conductor by extrusion of cross-linked polyethylene (XLPE) or silicone rubber. The inner sheath is formed by extrusion of low-smoke halogen-free flame-retardant TPU. The outer sheath is formed by extrusion of low-smoke halogen-free flame-retardant oil-resistant TPU or polyether-type TPE.

[0026] The bellows 300 is made of polyamide 66 and is slidably sleeved outside the wire harness 200. It is secured at each end with a limiting structure. (Example:) Figure 4 The limiting structure includes a silicone rubber sleeve 310 with a strip-shaped tightening opening 311. A cable tie is wrapped around the outside of the rubber sleeve 310 and tightened. As the cable tie tightens, a strong radial contraction force is generated on the outer wall of the rubber sleeve. This contraction force forces the rubber sleeve to undergo elastic deformation, and the width of the strip-shaped tightening opening on it becomes significantly narrower. The narrowing of the strip-shaped tightening opening leads to a reduction in the inner diameter of the rubber sleeve, thereby uniformly and tightly holding the internal corrugated tube and wire harness from all sides.

[0027] Assembly process: For wire harness preparation, T2 copper wire harnesses are assembled into conductors, and the main insulation layer, inner sheath, and outer sheath are extruded sequentially. A corrugated tube 300 is pre-fitted onto the outside of the outer sheath. Based on the required terminal length, wire strippers are used to precisely strip the outer sheath, inner sheath, and main insulation layer from the ends of the wire harness. The exposed length of the T2 copper conductor should meet the crimping process requirements. A circular terminal 210 is fitted onto the exposed conductor, and crimped using a professional crimping tool. The crimped terminal should not exhibit excessive deformation. A section of adhesive heat shrink tubing 211 is fitted onto the crimped area, and a heat gun is used to evenly heat the tubing from the middle outwards until it completely shrinks, melting the internal hot melt adhesive and extruding it evenly to form a smooth, sealed insulating protective layer. Pass one end of the wire harness through the bottom inlet of the connecting fastener 120 in the correct direction. The wire harness passes through the circumferential spring 124 and the inner sealing gasket 126 in sequence. Introduce the wire harness conductor end with the crimped terminal into the interior of the connecting fastener 120 and connect and fix it with the corresponding conductive piece on the back of the docking electrical connection part 110. Install a sealing ring on the inner wall of the cavity of the connecting fastener 120. Insert the end of the docking electrical connection part 110 with the buckle 111 into the open cavity of the connecting fastener in the correct direction and push it in evenly until a clear "click" sound is heard, indicating that the buckle has been fully engaged with the locking slot in the cavity.

[0028] Insert the cable tie 400 through the outer side of the loop spring 124 and place it above all the protrusions 1241. Tighten the cable tie until the loop spring 124 produces obvious but not excessive deformation, evenly tightening the outer sheath of the wire harness.

[0029] Slide the pre-inserted corrugated tube 300 to cover the wire harness section that needs protection, and adjust it to the predetermined position. Put a rubber sleeve 310 on each end of the corrugated tube 300, ensuring that the strip tightening opening 311 on the rubber sleeve 310 faces the operable direction. Wrap the cable tie around the outer wall of the rubber sleeve 310 and tighten it forcefully. As the cable tie tightens, the rubber sleeve will undergo elastic deformation, and the strip tightening opening 311 on it will gradually close, reducing the inner diameter, thereby uniformly and without damage securing the corrugated tube 300 and wire harness 200 inside.

[0030] Furthermore, the above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. The understanding of this specification should be based on those skilled in the art. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still make modifications or equivalent substitutions to the present invention. All technical solutions and improvements that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A high-voltage DC inverter wiring harness assembly for transport refrigeration equipment, comprising a wiring harness and a connector, characterized in that: The connector includes a docking electrical connection part and a connecting fastening part, which are connected by a snap-fit. At the bottom edge of the wire inlet of the connecting fastening part, a plurality of independent arc-shaped circumferential spring pieces extend outward at equal intervals. The wire harness passes through the middle of the circumferential spring pieces into the connecting fastening part and is connected to the docking electrical connection part through a terminal block. The outer ring of the circumferential spring pieces is fastened by a cable tie.

2. The high-voltage DC inverter wiring harness assembly for transport refrigeration equipment according to claim 1, characterized in that: Each of the circumferential spring pieces has a protrusion at the bottom of its outer wall, and the cable tie is positioned above the protrusion.

3. The high-voltage DC inverter wiring harness assembly for transport refrigeration equipment according to claim 2, characterized in that: The end of the connecting fastener that is connected to the docking electrical connection part is an open cavity, and the end of the docking electrical connection part with a buckle is inserted into the cavity.

4. The high-voltage DC inverter wiring harness assembly for transport refrigeration equipment according to claim 3, characterized in that: At least one sealing ring is provided on the inner wall of the cavity.

5. The high-voltage DC inverter wiring harness assembly for transport refrigeration equipment according to claim 3, characterized in that: A latch is provided on the inner cavity sidewall of the connecting fastener, and the latch engages with the buckle on the sidewall of the docking electrical connection part.

6. The high-voltage DC inverter wiring harness assembly for transport refrigeration equipment according to claim 1, characterized in that: A sealing gasket is provided inside the bottom inlet of the connection fastener, and the wire harness passes through the sealing gasket to form a seal at the connection.

7. The high-voltage DC inverter wiring harness assembly for transport refrigeration equipment according to claim 1, characterized in that: The wire harness includes a conductor and a sequentially wrapped main insulation layer, inner sheath, and outer sheath. A corrugated tube is provided on the outside of the wire harness. The conductor is formed by binding together multiple tin-plated soft copper wires after annealing. The main insulation layer is formed by extrusion of cross-linked polyolefin or silicone rubber material. The inner sheath is formed by extrusion of low-smoke halogen-free flame-retardant TPU material. The outer sheath is made of low-smoke halogen-free flame-retardant oil-resistant and wear-resistant TPU or polyether-type TPE material.

8. The high-voltage DC inverter wiring harness assembly for transport refrigeration equipment according to claim 1 or 7, characterized in that: The corrugated tube is slidably fitted outside the outer sheath, and a limiting structure is provided at both ends of its axial sliding stroke. The limiting structure fixes both ends of the corrugated tube to the wire harness to prevent the corrugated tube from coming out.

9. The high-voltage DC inverter wiring harness assembly for transport refrigeration equipment according to claim 8, characterized in that: The limiting structure consists of a rubber sleeve and a cable tie. The rubber sleeve is fitted onto the end of the corrugated pipe and has a through strip-shaped tightening opening along the axial direction. The cable tie is wrapped around the outer wall of the rubber sleeve.

10. The high-voltage DC inverter wiring harness assembly for transport refrigeration equipment according to claim 1, characterized in that: The terminal is a circular terminal, and the terminal is crimped and fixed to the conductor. A heat shrink tubing is sleeved at the crimping point between the terminal and the conductor.

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