Sealing device for vehicle inverter

Abstract

A terminal sealing device for a vehicle inverter includes an electrical terminal of the inverter, the electrical terminal being sealed into the inverter and having a distal portion of the terminal protruding to the outside of the inverter, wherein the terminal is sealed into the inverter by means of an elastic peripheral seal, the peripheral seal surrounding a portion of the terminal, and the seal being wedged between the terminal and at least a portion of the inverter.

Description

Technical Field

[0001] The present invention relates to an inverter used in an electric vehicle, and more particularly to a member and an arrangement for sealing electrical connectors or terminals of the inverter, such as pins and bus bars, to prevent fluid and / or particles from entering the inverter. Background Art

[0002] An inverter is a device that converts direct current into alternating current used in an electric vehicle motor. The inverter can change the speed of the motor rotation by adjusting the frequency of the alternating current. The inverter can also increase or decrease the power or torque of the motor by adjusting the amplitude of the signal. Generally, the inverter has electrical terminals in the form of bus bars or pins that protrude from the inverter to be properly connected to components outside the inverter.

[0003] It is crucial that no fluid (such as oil, fuel, or water) flows into the inverter. Therefore, the terminals need to form a fluid-tight connection (i.e., a sealed connection). The current prior art for preventing any contamination or additional liquid from flowing into the inverter through the connector (to avoid damaging the inverter and avoid possible loss of control of the vehicle) is to use dispense materials / sealing materials to seal the pins or bus bars. The dispense materials are expensive because base silicone resins cannot be used, but more expensive fluorosilicone resins are required. In addition, the process of using such dispense materials in manufacturing is a long process because curing time is required. It is also difficult to control the quality of the filling of the sealant / dispense material and the adhesion of the plastic / bus bar so that it is good enough during the service life of the vehicle. In addition, at the end of the assembly line, a leak test is also required to evaluate the leak level, and if the part fails, the part cannot be reused.

[0004] There is a customer requirement for no external leakage path to avoid damaging the inverter (short circuit due to particles / reduced performance due to oil). As mentioned above, base silicone resins cannot be used without damaging the e-machine, but fluorosilicone resins can be used without damaging the e-machine. Therefore, the current design uses a standard process to seal as "dispense material" to prevent leakage between the plastic and the bus bar from entering the inverter.

[0005] As mentioned above, from the perspective of cost and function, the two types of dispense materials are base silicone resin and fluorosilicone resin SIFEL2614 (expensive, $1 / g). Since the dispense materials do not adhere to plastics, bus bars, and other dispense materials (high scrap rate / waste rate), there is a leakage problem. Multiple inverters were damaged during testing. Summary of the Invention

[0006] In one aspect, a terminal sealing device for a vehicle inverter is provided. The terminal sealing device of the vehicle inverter includes an electrical terminal of the inverter, which is sealed into the inverter and has a distal portion protruding to the outside of the inverter. Wherein, the terminal is sealed into the inverter by means of an elastic peripheral seal, the peripheral seal surrounds a portion of the terminal, and the seal is wedged between the terminal and at least a portion of the inverter.

[0007] The at least a portion of the inverter may include a cut-out portion or a slot, the terminal protrudes outwardly through the cut-out portion or the slot, and the seal is wedged between the terminal and the periphery of the cut-out portion.

[0008] The portion of the inverter may be an inverter housing.

[0009] The portion of the inverter may be a ferrite core housing or a housing component.

[0010] The terminal may be a bus bar or a pin having a substantially rectangular cross-section.

[0011] The peripheral seal may be elongate.

[0012] The seal may include a peripheral wall and the thickness of the wall may vary or the wall has a portion with a conical / tapered cross-section.

[0013] The seal may be wedged between the terminal and a first component of the inverter and also wedged between the terminal and a second component of the inverter.

[0014] The seal may be wedged between a first component and a second component of the inverter.

[0015] The seal may be wedged between an upper ferrite core housing and a lower ferrite core housing.

[0016] The portion of the upper ferrite core housing into which the seal is wedged may be the (bottom) surface of the central portion of the upper ferrite housing.

[0017] The seal may be wedged between an upper ferrite core housing and a portion of the inverter housing wall.

[0018] At least one or both of the first inverter component and the second inverter component may include a slot portion, the terminal protrudes through the slot portion, and the seal is wedged between the terminal and the periphery of the cut-out portion.

[0019] Each of the slots may include a recess or a shoulder to receive or locate the seal in the portion of the inverter.

[0020] The recess or shoulder may generally correspond to the shape of the periphery of the seal.

[0021] The device may include a spring member adapted to wedge, hold or place the seal under compression.

[0022] The spring member may include a spring clip.

[0023] The device may include a member that connects the first inverter component to the second inverter component; this connecting member is also used to compress the seal. Description of the Drawings

[0024] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0025] - Figure 1a and Figure 1b A diagram of an electric vehicle inverter is shown, which shows a prior art sealing device;

[0026] - Figures 2a to 2e An example of an inverter sealing device according to an example of the present invention is shown;

[0027] - Figure 3a and Figure 3b A schematic diagram of a busbar seal according to an example is shown. Detailed Description

[0028] Figure 1a A schematic cross-sectional view of a known electric vehicle inverter is shown, which shows the salient components. The figure shows a prior art sealing device. The housing (e.g., plastic), generally designated 2, may include an upper (plastic) housing 12 and a (lower) plastic housing 13, and is located on the bottom / base 7 of the inverter (outer) housing designated by reference numeral 1.

[0029] The plastic housing accommodates the ferrite core 3, so there is ferrite both inside the upper plastic housing and the lower plastic housing. The terminal pins or busbars are denoted by reference numeral 4. These terminal pins or busbars protrude (i.e., extend) from the inner part of the inverter (i.e., inside the inverter housing), pass through the housing 2, and protrude at the bottom to the outside of the inverter. The outer ends / terminal ends of the pins / busbars are denoted by reference numeral 5. There is a seal / sealing interface 6 between the lower plastic housing and the base 7 (i.e., the bottom) of the inverter housing. The busbar can be considered to include two parts (a first (upper) part 8 and a second (lower) part 9), and the second (lower) part 9 protrudes outward from the inverter and needs to be sealed. The upper housing 12 and the lower housing 13 can be provided or considered as a single overmolded housing.

[0030] Figure 1b The ferrite core 3 is shown in more detail, and the reference numerals denote the same components as Figure 1a before. A first sealing / distributing material 10, which can be silicone resin for example (e.g., for the central part of the busbar), is used to embed part of the busbar into the housing 2. A second fluorosilicone resin distributing material 11 is used to seal the lower (outer) part (4 / 9) of the busbar to the lower part of the overmolded housing / seal within the lower part of the overmolded housing. As mentioned above, using fluorosilicone resin has the problem of high cost. The arrows A in both figures show possible leakage paths.

[0031] Figure 2a A schematic diagram (cross-sectional view of a cut-away part of the inverter housing) showing an example of the present invention is presented. Similarly, the reference numerals denote the same components as in the previous figures.

[0032] Figure 2b Shows Figure 2a a further cross-sectional view of the device, and Figure 2c shows a cross-sectional view of the device along the Figure 2b direction of arrow B. Figure 2c Shows a plurality of busbars / terminal pins 4.

[0033] Figure 2d Shows the exterior of the device. This shows the upper part 12 (made of plastic) of the ferrite housing 2 and the lower part 13 of the ferrite housing 2 which can also be made of plastic. The upper part 12 is connected to the lower part 13 by, for example, a tapping and bolt / screw device 21, and the tapping and bolt / screw device 21 also provides a member for fixing the device of the overmolded housing (including the upper and lower parts (12, 13 with the core 3)) to the lower wall 7 of the inverter housing. As can be seen from Figure 2a this, the lower wall 30 of the inverter housing has a cut-away part to expose the lower wall of the lower ferrite housing part. Thus, the distal ends of the busbars / terminals protrude directly outward from the assembly here.

[0034] It should be noted that alternatively, the bus bar can protrude outward from the inverter housing. Thus, in the example, it can be considered that the lower part 13 of the overmolding can be integral with a part 7 of the lower wall of the inverter housing (i.e., formed by a part 7 of the lower wall of the inverter housing). In other words, they can be not separate lower components, and the exterior 5 / 9 of the pin / bus bar protrudes directly outward from the inverter wall.

[0035] The lower wall of the (lower) ferrite housing and / or a part of the (bottom) wall of the inverter housing (where the seal is located) preferably has one or more cut-out portions or slots through which the terminal ends 5 of the corresponding bus bar / pin can protrude directly to the exterior.

[0036] Preferably, these cut-out portions / slots include grooved recesses or other members to provide shoulders that assist in the positioning of the seal.

[0037] The lower part of the ferrite housing (i.e., the lower housing) overmolds the bus bar, as Figure 2d shown. The central part of the upper part / upper housing has the reference numeral 14 in Figure 2b and Figure 2c .

[0038] Thus, in an example such as Figures 2a to 2d , the first dispensing material and the second dispensing material can be dispensed. Figures 2a to 2e The seal 15, which will be explained in more detail below, is shown in. The seal surrounds the bus bar at the exposed end (i.e., the position where it protrudes outward from the inverter (e.g., the inverter housing / ferrite housing (ends 5 / 9)).

[0039] The seal in this example is also wedged between the upper ferrite housing and the lower ferrite housing. Specifically, here, for example, it is wedged between the bottom surface of the central part of the upper ferrite housing and the upper surface of the lower ferrite housing 13.

[0040] Generally, a seal surrounding the bus bar / pin (commonly referred to as a terminal) at the position where the bus bar / pin protrudes outward is wedged between the terminal and one or more components of the inverter (assembly). Thus, slots can be provided in the inverter housing; the terminal protrudes outward through the slots, and the seal is wedged between the terminal and the periphery of the slots.

[0041] Alternatively and additionally, the seal can be wedged between the terminal (pin / bus bar) and two or more inverter components and / or wedged between two or more inverter components themselves. For example, wedged between the terminal and the corresponding surfaces of the upper ferrite housing and the lower ferrite housing, and / or the seal can be wedged between the corresponding upper and lower parts themselves, as Figure 2c shown.

[0042] In another example, the seal is wedged between the terminal and the corresponding surface of the upper ferrite housing and the corresponding surface of the inverter housing (e.g., lower) wall, and / or the seal can be wedged between the corresponding upper ferrite housing portion and the corresponding surface of the inverter (e.g., lower) wall. Similarly, slots can be provided in the lower ferrite housing / inverter housing here, where the terminal projects out from the outside through the slot and the seal is wedged between the terminal and the periphery of the slot, and optionally also against the surface of another inverter component. Similarly, the slot can have a recessed area or other structure to provide a neck or shoulder area to assist in positioning the seal.

[0043] In addition, an additional seal / sealing surface or cover 16 can be provided additionally.

[0044] Figure 2e is shown Figures 2a to 2d an enlarged (exploded) view of the device of. A compression spring 17 is provided to assist in the assembly of the magnetic core 3. The seal 16 will be compressed by 3 screws during assembly into the housing.

[0045] Figure 3a and Figure 3b A schematic view of the busbar seal is shown. The seal is a peripheral seal and is thus formed to generally conform around the terminal (busbar or pin). Since the busbar in the example can have a flat rectangular cross-section, the seal is correspondingly / appropriately formed such that it or its interior is also generally rectangular; that is, the inner periphery of the seal is also generally rectangular or elongate.

[0046] The seal can be formed such that the wall 18 (e.g., outer surface) of the seal is tapered, such that along a portion of the seal wall, the thickness of the seal increases in one direction (e.g., towards the bottom). Thus, Figure 3b the cross-section of the seal shown in is tapered (or at least partially tapered) (i.e., conical or partially conical) in form, i.e., a cone is formed. This allows for good assembly of the seal.

[0047] The inner surface 19 of the seal / sealing wall can have an inner shoulder or shelf 20, which is peripheral and is regarded as a protrusion in Figure 3b This helps with sealing.

[0048] The seal in the example can be positioned to be clamped between either the upper surface of the bottom of the inverter (lower) housing 13 or the upper bottom surface of the lower ferrite housing (in the cut-out area) and the end (face) of the central portion of the upper ferrite housing 14; and around the busbar.

[0049] Since the upper ferrite housing 12 can be connected to the lower housing 13 and / or the lower surface of the inverter housing, for example, by tapping and bolt / screw members 21, this will provide a certain degree of compression to ensure that the seal deforms and thereby provide a good seal (interface). The inner bottom surface of the lower inverter housing wall (i.e., the inner surface of the housing wall) or the bottom wall of the lower overmolding can include a recess / shelf (peripheral) portion to allow the seal to be assembled; the recess portion can correspond to the shape of the seal.

[0050] Thus, in the example, a busbar seal with a preferably suitable busbar shape design is provided. The seal is designed to seal the rectangular busbar all around and seal the plastic all around. The seal meets all specifications (temperature, stack-up, and pressure). The busbar can be designed using a special shape / deburring process to avoid any damage to the seal during assembly. The advantage is that the customer's requirements are met because there is no leakage. The price of the seal (about 0.45 euros per set) is currently cheaper than the allocated material (about 3 euros per set). The component / device has a simple assembly process, a shorter assembly cycle time, and better quality control.

[0051] The term "wedged between (component X and component Y)" can be considered as the term "positioned", alternatively, it can also be considered that the elastomeric seal deforms / is compressed between X and Y.

Claims

1. A terminal sealing device for a vehicle inverter, the terminal sealing device for the vehicle inverter including an electrical terminal of the inverter, the electrical terminal being sealed into the inverter and having a distal portion of the terminal protruding to the outside of the inverter, wherein, The terminal is sealed into the inverter by means of a spring member and an elastic peripheral seal, wherein the elastic peripheral seal includes a distal end, a proximal end, and a tapered outer wall connecting the distal end and the proximal end, wherein the thickness of the elastic peripheral seal increases from the distal end to the proximal end, the elastic peripheral seal surrounds a portion of the terminal, and the elastic peripheral seal is wedged between the terminal and at least a portion of the spring member or the inverter, wherein the spring member is adapted to wedge, hold the elastic peripheral seal or place the elastic peripheral seal under compression.

2. The terminal sealing device of the vehicle inverter according to claim 1, wherein, At least a portion of the inverter includes a cutout portion or a slot, the terminal projects outwardly through the cutout portion or the slot, and the elastic peripheral seal is wedged between the terminal and the periphery of the cutout portion.

3. The terminal sealing device of the vehicle inverter according to claim 1 or 2, wherein, At least a portion of the inverter includes an inverter housing.

4. The terminal sealing device of the vehicle inverter according to claim 1 or 2, wherein, At least a portion of the inverter includes a ferrite core housing or a portion of the ferrite core housing.

5. The terminal sealing device of the vehicle inverter according to claim 1 or 2, wherein, The terminal is a bus bar or a pin having a substantially rectangular cross-section.

6. The terminal sealing device of the vehicle inverter according to claim 1 or 2, wherein, The elastic peripheral seal is elongate.

7. The terminal sealing device of the vehicle inverter according to claim 1 or 2, wherein, The elastic peripheral seal is wedged between the terminal and a first component of the inverter and is also wedged between the terminal and a second component of the inverter, wherein the first component of the inverter includes an upper ferrite core housing, the second component of the inverter includes a lower ferrite core housing, wherein the upper ferrite core housing and the lower ferrite core housing are located on a lower wall of the inverter housing of the inverter, and the terminal extends through the upper ferrite core housing and the lower ferrite core housing to project to the outside of the inverter.

8. The terminal sealing device of the vehicle inverter according to claim 1 or 2, wherein, The elastic peripheral seal is wedged between a first component and a second component of the inverter, wherein the first component of the inverter includes an upper ferrite core housing, the second component of the inverter includes a lower ferrite core housing, wherein the upper ferrite core housing and the lower ferrite core housing are located on a lower wall of the inverter housing of the inverter, and the terminal extends through the upper ferrite core housing and the lower ferrite core housing to project to the outside of the inverter.

9. The terminal sealing device of the vehicle inverter according to claim 8, wherein, The portion of the upper ferrite core housing wedged with the elastic peripheral seal is the bottom surface of the central portion of the upper ferrite core housing.

10. The terminal sealing device of the vehicle inverter according to claim 8, wherein, The elastic peripheral seal is wedged between the upper ferrite core housing and the lower wall of the inverter housing.

11. The terminal sealing device of a vehicle inverter according to claim 7, wherein at least one or both of the first component and the second component of the inverter include a groove portion, the terminal projects through the groove portion, and the elastic peripheral seal is wedged between the terminal and the periphery of the groove portion.

12. The terminal sealing device of the vehicle inverter according to claim 11, wherein, Each of the groove portions in the groove portion includes a recess or a shoulder to receive or position the elastic peripheral seal in at least a portion of the inverter.

13. The terminal sealing device of the vehicle inverter according to claim 12, wherein, The recess or the shoulder substantially corresponds to the shape of the periphery of the elastic peripheral seal.

14. The terminal sealing device of the vehicle inverter according to claim 1 or 2, wherein, The spring member includes a spring clip.

15. The terminal sealing device of a vehicle inverter according to claim 8, wherein the terminal sealing device of the vehicle inverter includes a connecting member that connects the first component of the inverter to the second component of the inverter; the connecting member is also used to compress the elastic peripheral seal.

Images