JP2005012965A - Waterproof construction and motor for cable drawing portion - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a waterproof construction and a motor for a cable drawing portion, capable of reducing the number of parts, facilitating assembly, and providing cost reduction. <P>SOLUTION: A packing 5 in which a recessed portion 3 which orthogonally crosses with a longitudinal direction of a cable insertion hall 4, and in which a part of the insertion hall 4 opens at a wall surface, is formed at a wall surface of a housing 1. A sleeve-shaped packing 5 which is made by deformable material of which the outer periphery (outer diameter D) is larger than a recessed portion side opening 4c (opening diameter d) of the insertion hall 4, and of which the length L in a central shaft direction is formed so as to be larger than the opening dimension l in the insertion hall longitudinal direction of the recessed portion 3, is fitted in the recessed portion 3 while being elastically deformed. The cable 2 of the motor is inserted through one opening of the insertion hall 4. After the cable is inserted through an inside of the packing 5, it is drawn out of the other opening of the insertion hall 4. Under this constitution, the cable 2 can be tightened while the packing 5 is fixed at the housing 1 without using a bracket, a screw or the like. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a waterproof structure for a lead-out portion that pulls out a cable for supplying electric power, a signal, and the like inside a housing to the outside of the housing and an electric motor including the waterproof structure.
[0002]
[Prior art]
The electric motor may be required to have water resistance depending on the environment in which it is used. For example, in a motor mounted on an automobile or the like, a sealed housing (casing) made of an aluminum alloy or the like is used to prevent intrusion of muddy water or the like that is splashed up.
[0003]
In addition, an electric motor usually has a cable (also referred to as a harness or a lead wire) inserted through a cable insertion hole provided through the housing, and supplies electric power to the inside via this cable. Since control is performed, in an electric motor that is required to have water resistance, the opening outside the housing of the insertion hole (the cable lead-out portion) needs to have a waterproof structure.
[0004]
FIG. 4 is an axial cross-sectional view showing the structure of a conventional electric motor, and FIG. 5 is a schematic cross-sectional view illustrating a waterproof structure of a cable lead-out portion in this electric motor.
As shown in these drawings, the conventional waterproof structure in the lead-out portion of the cable 2 forms a step portion 14a by expanding the outer opening of the insertion hole 14 provided in the housing 1, and this step portion 14a. A substantially cylindrical packing (waterproof plug) 15 having an inner diameter slightly smaller than the outer diameter of the cable 2 is disposed therein, the cable 2 is inserted through the inner periphery of the packing 15, and then the packing 15 is fixed. Therefore, a method of fixing the bracket (presser plate) 16 to the housing 1 with a screw 17 or the like is employed.
[0005]
Further, as another known example, a mounting seat in which an annular packing is fitted in the outer opening of the insertion hole is disposed, and the cable is waterproofed by tightening the outer diameter of the cable with a packing presser and a screw (Patent Document 1). A method of fitting a packing having a portion made of a material elastic material into the inside of a cup-shaped mounting seat and tightening the outer diameter of the cable with a presser plate and a screw (Patent Document 2), or in order to waterproof the connection portion of the cable, A method of disposing an insulating adhesive and an insulating sealing body around the connecting portion (Patent Document 3) has been devised.
[0006]
[Patent Document 1] Japanese Utility Model Laid-Open No. 63-167361 [Patent Document 2] Japanese Utility Model Laid-Open No. 2-33572 [Patent Document 3] Japanese Utility Model Laid-Open No. 3-74166
[Problems to be solved by the invention]
However, in the conventional waterproof structure of the cable lead portion as described above, there is a problem that the number of parts increases because a bracket, a screw, and the like are required to fix the packing and tighten the cable. .
[0008]
In addition, the screwing of the bracket is not only complicated and causes an increase in work man-hours, but also requires a screw hole or the like for attaching the screw to be formed on the housing side in advance, which also increases the cost of the motor. It was.
[0009]
The present invention has been made in order to address the above-described problems, and has an object to provide a waterproof structure for a cable lead-out portion and an electric motor that can reduce the number of parts, can be easily assembled, and can be reduced in cost. It is said.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the waterproof structure of the cable lead-out portion according to claim 1 is formed with an insertion hole penetrating the housing in the housing, at a position corresponding to a longitudinal intermediate portion of the insertion hole. The housing wall surface is formed with a recess that is perpendicular to the longitudinal direction of the insertion hole and opens a part of the insertion hole in the wall surface, and is made of a deformable material, the outer peripheral portion of which is the recess side of the insertion hole A cylindrical packing that is larger than the opening and whose length in the central axis direction is larger than the opening dimension in the longitudinal direction of the insertion hole of the recess is stuffed into the recess while being deformed, and the cable is It is characterized by being inserted from the opening of the insertion hole, inserted through the inside of the cylindrical packing, and then pulled out from the opening of the other insertion hole.
[0011]
That is, according to the present invention, in the waterproof structure of the cable lead-out portion, the waterproof packing is not disposed at the outer opening of the cable insertion hole, but the packing is disposed at a substantially central portion of the housing thickness which is the middle portion in the longitudinal direction of the insertion hole. By trying to achieve the intended purpose.
[0012]
According to the first aspect of the present invention, the concave portion that opens a part of the insertion hole perpendicular to the longitudinal direction of the insertion hole is formed in the housing wall surface at a position corresponding to the longitudinal intermediate portion of the cable insertion hole. By forming the cable and pulling out the cable through the packing disposed in the recess, the packing is prevented from coming off (prevented from falling off).
[0013]
The packing is made of a deformable material, and has an outer diameter larger than the opening diameter of the insertion hole in the recess forming surface and a length in the central axis direction larger than an opening dimension in the longitudinal direction of the insertion hole of the recess. Since it is formed in a shape, when it is packed in this recess, both ends of the packing are brought into close contact with the recess forming surface due to elastic deformation, and the inner peripheral surface of the packing is inserted into the cable. Close contact with the outer peripheral surface to prevent water and the like from entering the housing.
[0014]
Here, the electric motor of the present invention is provided with a waterproof structure of the cable lead-out portion. (Claim 2)
[0015]
That is, the electric motor having the waterproof structure can tighten the cable while fixing the packing to the housing without using a bracket, a screw, or the like that has been conventionally required. Therefore, the electric motor of the present invention can reduce the number of parts and the number of work steps required for waterproofing the cable lead portion.
[0016]
Further, the waterproof structure of the cable lead-out portion makes it possible to achieve a reduction in the cost of the entire motor.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an axial sectional view showing the structure of an electric motor according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a portion P in FIG. FIG. 3 is an explanatory view showing the fitting between the recess 3 formed in the housing 1 and the packing 5 in this electric motor.
[0018]
The electric motor in the present embodiment is also an electric motor used for applications requiring water resistance, and has a watertight housing 1 made of an aluminum alloy or the like. In addition, since the internal mechanism of the electric motor in this example is the same as a well-known electric motor, detailed description is abbreviate | omitted.
[0019]
The feature of the electric motor in the present embodiment is the structure of the lead-out portion that pulls out the cable 2 to the outside. As with the conventional motor, this motor is also connected to an external power source or a control panel (not shown) through an insertion hole 4 provided in the housing 1 for supplying power and signals to the inside of the housing 1. It is connected. However, in the electric motor according to the present embodiment, the packing 5 responsible for waterproofing the lead-out portion of the cable 2 is not disposed in the outer opening 4a of the insertion hole 4 as in the conventional example. It is arranged in a recess 3 formed in a housing wall surface (in this example, an end surface 1x of a circumferential step portion 1a formed inside the housing 1) at a position corresponding to the middle portion in the longitudinal direction.
[0020]
As shown in FIG. 3, the recess 3 is formed so as to open a part of the insertion hole 4 toward the inside of the housing 1 perpendicular to the longitudinal direction of the insertion hole 4. Therefore, the concave side openings 4c and 4c of the insertion hole 4 are exposed at the longitudinal formation surfaces (wall surfaces 3x and 3x) of the concave portion 3, respectively.
[0021]
The packing 5 is formed in a substantially cylindrical shape using a deformable material (for example, a resin having elasticity such as rubber), and the outer peripheral portion (outer diameter D) is an opening on the concave portion side of the insertion hole 4. The axial length L is larger than 4c (opening diameter d) and larger than the opening dimension l in the longitudinal direction of the insertion hole 4 (D> d, L> l). That is, the length L of the packing 5 is designed so that an appropriate “crushing allowance” can be made in the axial direction with respect to the opening dimension l of the recess 3.
[0022]
Accordingly, when the packing 5 is fitted in the recess 3, the packing 5 is inserted while being compressed and deformed in the axial direction, and both end faces 5a, 5a of the packing 5 are formed in the longitudinal direction of the recess 3 (wall surface). 3x, 3x) are in close contact with each other, and the recess side openings 4c, 4c of the insertion holes are sealed. In addition, due to this axial compression, the inner diameter of the packing 5 is reduced, and the outer diameter of the cable 2 inserted through the packing 5 is tightened.
[0023]
In addition, by pulling out the cable 2 through the packing 5, the packing 5 can be prevented from coming off from the concave portion 3 (preventing from coming off) at the same time.
[0024]
With the above configuration, the electric motor in the present embodiment can realize the waterproof structure of the cable 2 lead-out portion without using a bracket, a screw, or the like used in the conventional waterproof structure.
[0025]
In addition, this invention is not limited to the example in this embodiment, A various deformation | transformation is possible according to the position which provides the penetration hole of a cable. For example, the recess on the wall surface of the housing into which the packing is fitted is not necessarily provided inside the housing, and may be provided on the wall surface outside the housing. The cross-sectional shape of the recess is not limited to the example in this embodiment. The shape of the recess may be a so-called dovetail shape in which the size of the recess opening is smaller than the size of the bottom, and conversely, the size of the recess opening may be larger than the size of the bottom.
[0026]
Further, the material of the packing is not particularly limited, and may be appropriately selected according to the environment in which the electric motor is used.
[0027]
Still further, the present invention is not limited to the above-described embodiment, and is applicable to all devices that include a housing and a cable and need to waterproof the lead-out portion of the cable that passes through the housing. Of course.
[0028]
【The invention's effect】
As described in detail above, according to the waterproof structure of the cable lead portion of the present invention, the outer diameter of the cable can be tightened while fixing the packing to the housing without using a bracket or a screw. Therefore, the electric motor of the present invention has a small number of parts necessary for waterproofing the cable lead portion, is easy to assemble, and can reduce costs.
[Brief description of the drawings]
FIG. 1 is an axial sectional view showing a structure of an electric motor according to an embodiment of the present invention.
FIG. 2 is an enlarged view of a portion P in FIG.
FIG. 3 is an explanatory view showing a fit between a recess 3 and a packing 5 in the electric motor according to the embodiment of the present invention.
FIG. 4 is an axial sectional view showing a structure of a conventional electric motor.
FIG. 5 is a schematic cross-sectional view illustrating a waterproof structure of a cable lead portion in a conventional electric motor.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Housing 1a Circumferential step part 1x End surface 2 Cable 3 Recess 3x Recess formation surface (wall surface)
4 Insertion hole 4a Outer opening 4b Inner opening 4c Recessed side opening 5 Packing 5a End face 14 Insertion hole 14a Step 15 Packing 16 Bracket (Presser plate)
17 Screw

Claims (2)

An insertion hole that penetrates the housing is formed in the housing, and a part of the insertion hole is formed on the housing wall surface at a position corresponding to the longitudinal intermediate portion of the insertion hole so as to be orthogonal to the longitudinal direction of the insertion hole. While forming a recess to be opened in the wall surface,
A cylindrical packing made of a deformable material, the outer periphery of which is larger than the recess-side opening of the insertion hole, and whose length in the central axis direction is larger than the opening dimension of the insertion hole in the longitudinal direction of the insertion hole Stuffed into this recess while deforming,
A waterproof structure for a cable lead-out portion, wherein a cable is inserted from one insertion hole opening, inserted through the inside of the cylindrical packing, and then drawn out from the other insertion hole opening. An electric motor comprising the waterproof structure of the cable lead-out portion according to claim 1.

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