Sealing assembly, cable for driving motor and sealing method thereof

Abstract

The invention relates to a sealing assembly, a cable for a driving motor and a sealing method thereof. The electrical cable (114) includes a plurality of conductors (102) with respective insulators and all covered by a sheath (108). The seal assembly (100) includes a seal member (112), a first portion (106) having an inlet, and a second portion (104) having a plurality of outlets. The sealing member (112) is slidably inserted over the cable (114) through the first portion (106) such that the first portion (106) covers the sheath (108) and the plurality of conductors (102) of the cable (114) pass through the plurality of outlets of the second portion (104). The sealing member (112) is made of a heat-shrinkable tube which, upon application of heat, shrinks the first portion (106) and the second portion (104) and seals any gaps therein, characterized in that at least one airflow path (110) is formed between the first portion (106) and the jacket (108) of the cable (114).

Description

Technical Field

[0001] The present disclosure relates to a sealing assembly for a cable of a drive motor, a cable for a drive motor, and a method for sealing the cable. Background Art

[0002] In drive motors for two-wheelers and other types of vehicles, water ingress into the drive motor is a serious problem. It can cause incipient failures and can lead to rusting inside the motor, followed by motor seizure. In existing designs, water does not enter from the motor area (seals, shafts, covers, etc.), but the cable harness connecting the motor to the motor control unit is not IP67 certified. Given the benefits of the breathing feature, the harness is intentionally kept this way to ensure the durability of the motor. However, the current breathing capability also results in water ingress into the motor during heavy rain / high pressure water washdowns.

[0003] The solution currently used in the market is to inject glue into the opening of the harness to a certain depth (up to 5cm) to seal the connection end 204 of the cable 114. But this solution has potential durability issues, and the effect depends entirely on the quality of the glue used. The concept is also to completely seal the motor, thereby removing the breathing function of the harness. The glue must also be able to cope with road vibrations, high temperature operation (>100 degrees Celsius), and its effectiveness throughout the life of the motor is currently unknown. Jelly-filled cable harnesses are also available, but are rarely used because they are expensive.

[0004] According to the prior art DE2927558 discloses a waterproof clamp and cable terminal - with back-stripped conductors and sheaths, which are enclosed as a clamp and vulcanized to the device (appts). The clamp and waterproof connector are used for the leads of electrical equipment (especially for motor vehicle instruments). The connector includes a thermoplastic grommet, which is vulcanized onto the end of the electrical lead and has a sleeve-like section as an extension of each individual insulated conductor in the cable. The cable is fed into the end of the sleeve grommet so that the outer sheath of the cable is clamped and protected. Each insulated individual stranded conductor is stripped from the back so that the insulation part is fed forward into the extension of the sleeve grommet unit. The exposed stranded conductors extending from the grommet extension are further protected by ferrules, which are slid over the end and glued or vulcanized to the main grommet unit. The outer surface of the sleeve grommet is molded into an annular formation to permit a vulcanization seal into the housing of the device at the entry point. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Embodiments of the present disclosure are described with reference to the following drawings:

[0006] Figure 1A sealing assembly for a cable of a drive motor according to an embodiment of the present invention is illustrated;

[0007] Figure 2 A perspective view illustrating an assembled seal for a cable of a drive motor according to an embodiment of the present invention, and

[0008] Figure 3 A flow chart of a method for sealing an exposed end of an electrical cable of a drive motor according to the present invention is illustrated. DETAILED DESCRIPTION

[0009] Figure 1 The sealing assembly of the cable for driving a motor according to an embodiment of the present invention is illustrated. The cable 114 includes a plurality of conductors 102 with corresponding insulation and all covered by a sheath 108 (also referred to as an outer sheath). The plurality of conductors 102 are partially exposed from the insulation and the sheath 108 for connection to a battery and a control unit of a vehicle. The sealing assembly 100 includes a sealing member 112 (also referred to as a branch pin), a first portion 106 having an inlet, and a second portion 104 having a plurality of outlets. The sealing member 112 is slidably inserted on the cable 114 through the first portion 106, so that the first portion 106 covers the sheath 108 of the cable 114, and the plurality of conductors 102 of the cable 114 pass through the plurality of outlets of the second portion 104. The sealing member 112 is made of a heat shrink tube which shrinks the first portion 106 and the second portion 104 when heat is applied and seals the gap (any gap therein) between the sealing member 112 and the cable 114, characterized in that at least one airflow path 110 is formed between the first portion 106 of the sealing member 112 and the sheath 108 of the cable 114.

[0010] exist Figure 1 In FIG. 1 , two views are shown. The first view 116 shows the opening / connection end 204 of the cable 114 (in Figure 2 108. The second view 118 shows a cross-sectional view of the sealing member 112 fixed at the opening / connection end 204 of the cable 114. The cable 114 is a multi-core cable having at least two or more conductors 102. The conductor 102 is insulated and partially stripped at the opening / connection end 204 where the connection will be made. Therefore, the conductor 102, the insulator and the sheath 108 are collectively referred to as the cable 114. There is an air gap between the sheath 108 and the conductor 102, which exists throughout the length of the cable 114.

[0011] According to an embodiment of the present invention, the at least one airflow path 110 is along the first portion 106 and communicates with the air gap in the cable 114. According to another embodiment, before applying heat, an adhesive material is filled between the sealing member 112 and the cable 114. According to yet another embodiment, the at least one airflow path 110 is formed in a straight line or a curve. The at least one airflow path 110 starts from the input end of the first portion 106, extends in or inside the first portion 106 until the starting point of the second portion 104, and then connects with the air gap of the cable 114.

[0012] According to an embodiment of the present invention, the at least one airflow path 110 is formed by inserting an element (not shown) between the first portion 106 of the sealing member 112 and the jacket 108 of the cable 114 before applying heat and removing the element after applying heat. The element acts as a placeholder that is positioned before applying heat and then pulled out as required after the heat shrink process is completed.

[0013] According to an embodiment of the present invention, a cable 114 of a drive motor is provided, or a drive motor with a cable 114 is provided. The cable 114 includes a plurality of conductors 102 with corresponding insulation and all covered by a sheath 108. The plurality of conductors 102 are partially exposed from the insulation and the sheath 108 for connection. The cable 114 includes a sealing member 112 (also referred to as a branch pin), which has a first portion 106 with an inlet and a second portion 104 with a plurality of outlets. The sealing member 112 is slidably inserted on the cable 114 through the first portion 106, so that the first portion 106 covers the sheath 108 of the cable 114, and the partially exposed plurality of conductors 102 pass through the plurality of outlets of the second portion 104. The sealing member 112 is made of a heat shrink tube that shrinks the first part 106 and the second part 104 when heat is applied and seals any gap therebetween, or is inserted onto the heat shrink tube, and is characterized in that at least one airflow path 110 is formed between the first part 106 of the sealing member 112 and the sheath 108 of the cable 114.

[0014] According to an embodiment of the present invention, the at least one airflow path 110 is formed in any one of a straight line or a curve. The at least one airflow path 110 is in flow communication with the air gap in the cable 114. According to another embodiment, before applying heat, an adhesive material is filled between the sealing member 112 and the cable 114. According to yet another embodiment of the present invention, the at least one airflow path 110 is formed by inserting an element between the first portion 106 of the sealing member 112 and the sheath 108 of the cable 114 before applying heat and removing the element after applying heat.

[0015] According to an embodiment of the present invention, each of the airflow paths 110 is formed with a diameter of 1 mm. In another embodiment, the at least one airflow path 110 includes two airflow paths 110 formed on opposite sides of the diameter of the cable line 114. The opening size of the at least one airflow path 110 and the number of the airflow paths 110 are designed as required and are not limited to the examples provided.

[0016] According to an embodiment of the present invention, the drive motor is any one selected from the group consisting of a hub motor or a side-mounted motor (having a neodymium magnet), or as a motor mounted on a wheel of an electric vehicle or a hybrid vehicle.

[0017] Figure 2 A perspective view of an assembled seal for a cable for a drive motor according to an embodiment of the present invention is illustrated. The multi-core conductors 102 are shown as being four in number, however, this should not be understood in a limiting manner. A multi-core cable may be two or more conductors 102. Figure 2 In the embodiment of the present invention, the at least one airflow path 110 is clearly shown. The connection end 204 of the cable 114 is away from the opening 202 of the at least one airflow path 110 .

[0018] According to an embodiment of the present invention, an application of a sealing assembly 100 is provided. Consider that a sealing member 112 is filled with a jelly-based adhesive. The sealing member 112 includes an inlet and multiple outlets. When the sealing member 112 (which is a heat shrink tube) is heated, the sealing member 112 shrinks and is firmly attached to the surface of the cable 114. The sealing member 112 ensures that there is no open gap (water can enter the cable 114 through these open gaps). The adhesive jelly inside the sealing member 112 ensures that each outlet (or branch port) is well sealed when shrinking. These sealing members 112 work very well with high temperature operations and do not pose a threat to water entry.

[0019] According to the present invention, a process for sealing using a sealing member 112 is provided. The first step includes assembling a jelly-filled sealing member 112 (heat-shrinkable tube) before assembling the cable 114. The next step includes sealing the sealing member 112 to the cable 114 using a heat shrinking process. The heat shrinking process is controlled so that after heating, there is an essential gap provided at the entrance portion. This maintains the breathing ability of the cable 114 of the drive motor. The cable 114 or the drive motor is subjected to a leak test at the end of the motor assembly line to ensure that the sealing member 112 is completely sealed. Figure 3 The specific steps are defined in .

[0020] Figure 3The flowchart of the method for sealing the exposed end of the cable of the drive motor according to the present invention is illustrated. The method comprises a plurality of steps, wherein step 302 comprises: inserting the sealing member 112 across the connection end 204 of the cable 114. The sealing member 112 comprises a first part 106 of the sheath 108 covering the cable 114 and a second part 104 with a plurality of outlets, through which a plurality of conductors 102 of the cable 114 pass. Step 304 comprises: applying heat to the sealing member 112 to shrink it and seal any gap between the sealing member 112 and the cable 114. The method is characterized in that step 306 comprises: before applying heat, inserting an element between the first part 106 of the sealing member 112 and the sheath 108 of the cable 114. Step 308 comprises: after the heat shrinking process is completed, removing the element. Step 306 is completed before step 306, and step 308 is performed after step 304.

[0021] According to an embodiment of the present invention, the sealing member 112 prevents water from entering without losing the breathing ability of the drive motor. The sealing assembly 100 according to the present invention ensures that no moisture is trapped inside the drive motor during manufacturing, pressure does not build up inside the drive motor as the temperature rises during operation, and it is very simple to test the motor for leaks on the assembly line. The breathing ability of the drive motor is also maintained.

[0022] It should be understood that the embodiments explained in the above description are only illustrative and do not limit the scope of the present invention. Many such embodiments and other modifications and variations to the embodiments explained in the description can be envisioned. The scope of the present invention is limited only by the scope of the claims.

Claims

1. A sealing assembly (100) for a cable (114) for driving a motor, the cable (114) comprising a plurality of conductors (102) with corresponding insulation and all covered by a sheath (108), the plurality of conductors (102) being partially exposed from the insulation and the sheath for connection, the sealing assembly (100) comprising: A sealing member (112) comprising a first portion (106) having an inlet and a second portion (104) having a plurality of outlets, wherein the sealing member (112) is slidably inserted on the cable (108) through the first portion (106), so that the first portion (106) covers the jacket (108) of the cable (108), and the plurality of conductors (102) pass through the plurality of outlets of the second portion (104). The sealing member (112) is made of a heat shrink tube which shrinks the first portion (106) and the second portion (104) and seals any gap therebetween when heat is applied, and is characterized in that at least one airflow path (110) is formed between the first portion (106) of the sealing member (112) and the jacket (108) of the cable (114).

2. The sealing assembly (100) according to claim 1, wherein: The at least one airflow path (110) is along the first portion (106) of the sealing member (112) and communicates with an air gap within the electrical cable (114).

3. The sealing assembly (100) according to claim 1, wherein: Prior to applying heat, an adhesive material is filled between the sealing member (112) and the cable wire (114).

4. The sealing assembly (100) according to claim 1, wherein: The at least one air flow path is formed in a straight line or a curved line.

5. The sealing assembly (100) according to claim 1, wherein: The at least one airflow path (110) is formed by inserting an element between the first portion (106) and the jacket (108) of the cable (114) before applying heat and removing the element after applying heat.

6. A cable (114) for driving a motor, the cable (114) comprising a plurality of conductors (102) with corresponding insulation and all covered by a sheath (108), the plurality of conductors (102) being partially exposed from the insulation and the sheath (108) for connection, the cable (114) comprising: A sealing member (112) having a first portion (106) with an inlet and a second portion (104) with a plurality of outlets, wherein the sealing member (112) is slidably inserted on the cable (114) through the first portion (106), so that the first portion (106) covers the jacket (108) of the cable (114), and the partially exposed plurality of conductors (102) pass through the plurality of outlets of the second portion (104), The sealing member (112) is made of a heat shrink tube which shrinks the first portion (106) and the second portion (104) and seals any gap therebetween when heat is applied, and is characterized in that at least one airflow path (110) is formed between the first portion (106) of the sealing member (112) and the jacket (108) of the cable (114).

7. The electrical cable (114) according to claim 6, wherein: The at least one airflow path (110) is formed in a straight line or a curved line, and wherein the at least one airflow path (110) is in flow communication with an air gap within the cable (114).

8. The electrical cable (114) according to claim 6, wherein: Prior to applying heat, an adhesive material is filled between the sealing member (112) and the cable wire (114).

9. The electrical cable (114) according to claim 6, wherein: The at least one airflow path (110) is formed by inserting an element between the first portion (106) of the sealing member (112) and the cable (114) before applying heat and removing the element after applying heat.

10. A method for sealing an exposed end of an electrical cable (114) for a drive motor, the method comprising the steps of: A sealing member (112) is inserted across the connection end (204) of the cable (114), the sealing member (112) comprising a first portion (106) covering a sheath (108) of the cable (114) and a second portion (104) having a plurality of outlets through which a plurality of conductors (102) of the cable (114) pass, Heat is applied to the sealing member (112) to cause it to shrink and seal any gaps therein, characterized in that inserting an element between the first portion (106) of the sealing member (112) and the jacket (108) of the cable (114) prior to applying the heat, and The component is removed after the heat shrink process is completed.

Images