JP2004304984A - Waterproofing structure of cable through mouth - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a more excellent waterproofing structure of a cable through mouth. <P>SOLUTION: The waterproofing structure of a cable through mouth 201 is provided in a case 200 which houses electronic devices 300, 400 and 500. The case 200 is made by assembling a plurality of case members 210, 220, 230 and 240. The cable through mouth mounts a grommet 600 penetrating a cable 700 between the plurality of the case members. The waterproofing structure of the cable through mouth 201 includes a lip part 621 for sealing a gap to the cable, a clamping part 622 for preventing the cable from being moved due to the intrusion of the cable into a coating layer 720, and a groove part 623 for separating the lip part and the clamping part provided on the inner peripheral surface 620 of the grommet. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a waterproof structure of a cable passage provided in a case for housing an electronic device.
[0002]
[Prior art]
In a case for housing an electronic device such as a motor, a through hole of an external connection means of the electronic device is waterproofed by attaching a grommet. The waterproof structure of the motor case is also disclosed in Patent Documents 1 and 3 and the like.
[0003]
[Patent Document 1] JP-A-9-93854 [Patent Document 2] JP-A-11-146599 [Patent Document 3] JP-A-2003-9449 [Problems to be Solved by the Invention]
That is, when a cable is inserted into the case as an external connection means, a cable passage is provided in the case, and a grommet that penetrates the cable is attached to the cable passage. Generally, a case is formed by assembling a plurality of case members, and the grommet is mounted between the plurality of case members. It is important that the waterproof structure of such a cable passage be assured of waterproofness, that it is easy to assemble, and that the cable has a strong pull-out resistance. A waterproof structure more suitable for these conditions is required.
[0004]
The present invention has been made in view of such circumstances, and an object thereof is to provide a more excellent waterproof structure of a cable passage.
[0005]
[Means for Solving the Problems]
According to a first aspect of the present invention, in the waterproof structure of a cable passage provided in a case for housing an electronic device, the case is formed by assembling a plurality of case members, and the cable passage is provided with the plurality of case members. A grommet that penetrates the cable is attached between the case members, and a lip portion that seals a gap between the cable and the inner peripheral surface of the grommet, and the cable moves by biting into a coating layer of the cable. And a groove for separating the lip portion from the fastening portion. According to such a configuration, an excellent waterproof structure for the cable passage is obtained.
[0006]
That is, according to the waterproof structure of the cable passage of the present invention, the gap between the grommet and the cable is ensured by the lip provided on the inner peripheral surface of the grommet being pressed against the cable. In addition, the pull-out resistance of the cable is ensured by the fastening portion biting into the coating layer of the cable. Furthermore, according to the present invention, according to the grommet according to the present invention, when the fastening portion cuts into the coating layer of the cable, the escape of the coating layer generated at the fastening portion may adversely affect the press-contact state between the cable and the lip portion. The inner peripheral surface has a groove for separating the lip portion and the tightening portion, so that the escape of the coating portion can be absorbed by the groove. That is, the grommet in the present invention is configured to rationally secure the pull-out resistance of the cable together with the waterproofness. The use of such a grommet also has the advantage that the electronic device and the case can be easily assembled.
[0007]
The invention described in the second aspect of the present invention is the waterproof structure of the cable passage in the first aspect, wherein a second lip portion that seals a gap with the case member is provided on an outer peripheral surface of the grommet. .
[0008]
That is, according to the waterproof structure of the cable passage of the present invention, the gap between the grommet and the case member is ensured by the second lip provided on the outer peripheral surface of the grommet being pressed against the case member.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, specific examples of the present invention will be described in detail with reference to the drawings.
[0010]
The motor 100 shown in FIGS. 1 and 2 is a brushless DC motor for traveling mounted on a vehicle and used. The motor 100 includes a motor case 200 in which a rotor 300 as an electronic device, a stator 400, and control means 500 of the motor 100 are housed. The motor case 200 includes a first case member 210 into which the stator 400 is fitted, a second case member 220 that partitions the inside of the first case member 210, and a third case member 230 that closes the opening of the first case member 210. , And a fourth case member 240 that covers the third case member 230. Each case member 210, 220, 230, 240 is a member made of an aluminum alloy having a predetermined shape. The rotor 300 is provided with a small gap between the rotor 300 and the stator 400, and the shaft portion 310 is bridged between the first case member 210 and the second case member 220 via the bearing 320. The control means 500 is supported by the second case member 220 and the third case member 230, and is connected to the coil 410 of the stator 400 by wiring. The fourth case member 240 is a heat sink provided with the radiation fins 241, and heat transmitted from the control unit 500 to the third case member 230 is radiated from the fourth case member 240 to the outside. Further, as shown in FIG. 3, key portions of the third case member 230 and the fourth case member 240 are screwed to ends of the first case member 210 with male screw parts 250. At an end of the third case member 230, a sealing means 231 (gasket) for sealing a gap with the end of the first case member 210 is provided.
[0011]
Further, a through hole 201 of a cable 700 for connecting the inside and the outside of the motor case 200 is provided at a key point of the motor case 200 of this example. The cable passage 201 is configured by mounting a grommet 600 penetrating the cable 700 between the first case member 210 and the third case member 230. The end of the first case member 210 is provided with a concave portion 211 into which the grommet 600 is fitted. That is, the waterproof structure of the cable passage 201 of the present embodiment is provided with the grommet 600.
[0012]
As shown in FIGS. 4 to 7, the grommet 600 of the present example is a rubber member having appropriate hardness, and includes a pair of flanges 610 that sandwich the ends of the first case member 210 and the third case member 230. Have. The cable 700 according to the present embodiment is an interface for transmitting an external command to the control unit 500, and includes a multi-core electric wire 710 provided with a rubber covering layer 720.
[0013]
The inner peripheral surface 620 of the grommet 600 that penetrates the cable 700 has a plurality of annular lips 621 that seal the gap with the cable 700, and prevents the cable 700 from moving by cutting into the coating layer 720 of the cable 700. An annular fastening portion 622 and an annular groove portion 623 separating the lip portion 621 and the fastening portion 622 are provided. The inner diameter of the lip portion 621 and the tightening portion 622 is set to be somewhat smaller than the outer diameter of the cable 700. The outer diameter of the groove 623 is set to be somewhat larger than the outer diameter of the cable 700. According to the groove portion 623, an annular hollow space is formed between the inner peripheral surface 620 of the grommet 600 and the cable 700.
[0014]
Further, on the outer peripheral surface 630 of the grommet which comes into contact with the ends of the first case member 210 and the third case member 230, a plurality of annular second lip portions 631 for sealing a gap between the case members 210 and 230 are provided. Provided.
[0015]
The grommet 600 is provided with a cut 640 extending from the side surface to the inner peripheral surface 620, and the cable 700 is pushed into the inner peripheral surface 620 while opening the cut 640. Alternatively, the cable 700 can be penetrated while increasing the diameter of the inner peripheral surface 620 using a predetermined jig. In this case, the cut 640 may not be provided.
[0016]
According to such a configuration, the grommet 600 of the cable passage 201 is pressed together with the first case member 210 and the third case member 230 while being screwed, and the gap between the grommet 600 and the cable 700 is formed by a plurality of lip portions. 621 is secured by pressing against the cable 700. The lip portion 621 is in a state of being crushed by the cable 700. Further, the pull-out resistance of the cable 700 is ensured by the fastening portion 622 biting into the covering layer 720 of the cable 700. Here, the clearance of the coating layer 720 caused by the fastening portion 622 biting into the coating layer 720 of the cable 700 is absorbed by the groove portion 623, which adversely affects the press-contact state between the cable 700 and the lip portion 621. Don't worry.
[0017]
Further, the gap between the grommet 600 and the first case member 210 and the third case member 230 is ensured by the second lip portion 631 being pressed against the case members 210 and 230. The second lip portion 631 is in a state of being crushed by the case members 210 and 230. Generally, at the joint between the case members 210 and 230 (the portion A in FIG. 5), it is difficult to eliminate the gap. According to this example, as shown in FIG. 8, the second lip portion 631 Is appropriately deformed and enters a small gap between each of the case members 210 and 230, so that there is no fear that the clearance is incompletely eliminated. 8A shows a state of the second lip portion 631 before screwing the first case member 210 and the third case member 230, and FIG. 8B shows a state of the second lip portion after screwing them. 631 is shown.
[0018]
As shown in FIG. 9, the grommet 600 can be provided with a plurality of inner peripheral surfaces 620 through which the cables 700 are inserted. Each inner peripheral surface 620 is provided with a lip portion 621, a fastening portion 622, and a groove portion 623, respectively. The grommet 600 illustrated in the figure penetrates three cables 700. One of the three cables 700 is an interface for transmitting a command from the outside to the control unit 500, and the other two are a pair of power supply wires for supplying power to the control unit 500.
[0019]
As described above, the waterproof structure of the cable passage of this example is an extremely excellent structure configured in consideration of the waterproofness, the assembling property, and the pull-out resistance of the cable. It can be used favorably as a means to secure. Of course, such a waterproof structure can be applied to not only the motor case but also various other cases.
[0020]
【The invention's effect】
The present invention relates to a waterproof structure of a cable passage provided in a case for housing an electronic device, wherein the case is formed by assembling a plurality of case members, and the cable passage is provided between the plurality of case members. A grommet that penetrates the grommet is provided, and an inner peripheral surface of the grommet has a lip portion that seals a gap with the cable, and a tightening portion that bites into a coating layer of the cable and prevents the cable from moving. And a groove for separating the lip portion and the tightening portion from each other. According to such a configuration, an excellent waterproof structure of the cable passage can be obtained.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a motor according to a specific example of the present invention.
FIG. 2 is an exploded sectional view showing a motor according to a specific example of the present invention.
FIG. 3 is a cross-sectional view showing screwing of a case member according to a specific example of the present invention.
FIG. 4 is a side sectional view showing a cable passage according to a specific example of the present invention.
FIG. 5 is a front cross-sectional view showing a cable passage according to a specific example of the present invention.
FIG. 6 is a front view showing a grommet according to a specific example of the present invention.
FIG. 7 is a side sectional view showing a grommet according to a specific example of the present invention.
FIG. 8 is a front cross-sectional view showing a main part of a cable passage according to a specific example of the present invention, in which (a) is a second lip portion before screwing a first case member and a third case member. (B) shows the state of the second lip after screwing them.
FIG. 9 is a front view showing a grommet according to a specific example of the present invention.
[Explanation of symbols]
REFERENCE SIGNS LIST 100 motor 200 motor case 201 cable passage 210 first case member 211 concave portion 220 second case member 230 third case member 231 sealing means 240 fourth case member 241 radiating fin 250 male screw component 300 rotor 310 shaft portion 320 bearing 400 stator 400 Coil 500 Control means 600 Grommet 610 Flange 620 Inner peripheral surface 621 Rip 622 Tightening part 623 Groove 630 Outer peripheral surface 631 Second lip 640 Cut 700 Cable 710 Multi-core electric wire 720 Coating layer

Claims (2)

In the waterproof structure of the cable passage provided in the case for storing the electronic device,
The case is formed by assembling a plurality of case members,
The cable passage is provided with a grommet that penetrates a cable between the plurality of case members,
On the inner peripheral surface of the grommet, a lip portion that seals a gap with the cable, a tightening portion that cuts into the coating layer of the cable to prevent the cable from moving, the lip portion and the tightening portion. A waterproof structure for a cable passage, characterized by having a groove for separating the cable. The waterproof structure for a cable passage according to claim 1, wherein a second lip portion is provided on an outer peripheral surface of the grommet to seal a gap with the case member.

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