JP4689362B2 - Seal structure of cable insertion part - Google Patents

Description

  The present invention relates to a seal structure of a cable insertion portion in a vehicle in which a cable such as a power cable is inserted from the lower surface side of a vehicle body floor.

In an electric vehicle or a so-called hybrid vehicle, many electrical devices with heat generation such as a battery, an inverter for driving a motor, and a converter for voltage conversion are mounted. In many of this type of vehicle, the above-described electrical equipment is disposed in an electrical box, and the heat of the electrical equipment radiated in the electrical box is discharged to the outside by a fan.
In addition, when the electrical box is arranged at the rear part of the rear seat, etc., an electrical cable for connecting these to the lower surface side of the vehicle body floor is connected to connect the electrical equipment in the electrical box to the motor in the engine room. May be laid.

In this case, the end of the electrical cable on the vehicle body rear side passes through the vehicle body floor and the electrical box and is connected to the electrical component. However, as shown in FIG. 9, the cable insertion holes 103 of the vehicle body floor 101 and the electrical box 102 are connected. , 104 are sealed between the electrical cable 107 by separate grommets 105, 106, respectively. That is, the vehicle body side cable insertion hole 103 is sealed between the electrical cable 107 by the first grommet 105 so that muddy water and dust from the vehicle body lower surface side do not enter, and the box side cable insertion hole 104 is sucked by the fan. The second grommet 106 is sealed between the electrical cable 107 so that the pressure does not escape from the passage 108 in the electrical box 102 (see, for example, Patent Document 1).
JP 2003-156150 A

  However, this conventional cable insertion portion seal structure is configured such that the gap between the vehicle body side cable insertion hole 103 and the electrical cable 107 and the space between the box side cable insertion hole 104 and the electrical cable 107 are sealed by separate grommets 105 and 106, respectively. Therefore, the increase in the number of parts causes an increase in manufacturing cost, and the assembly of the grommets 105 and 106 into the cable insertion holes 103 and 104 and the insertion work of the electrical cable 107 into the grommets 105 and 106 are complicated. There is a problem of becoming.

  Therefore, the present invention can easily and reliably seal each peripheral portion of the vehicle body side cable insertion hole and the box side cable insertion hole with respect to the electrical cable without increasing the number of parts. An object of the present invention is to provide a cable insertion portion seal structure that can reduce the cost and cost.

As means for solving the above-mentioned problems, the invention described in claim 1 is an electrical equipment box (for example, an electric equipment box (for example, a motor inverter 8, a compressor inverter 10, and a battery 50 in an embodiment described later)). The electrical box 50 in the embodiment described later is disposed with a gap above the vehicle body floor (for example, the vehicle body floor 19 in the embodiment described later), and the vehicle body side cable insertion hole (for example, described later) in the vehicle body floor and the electrical box. The vehicle body side cable insertion hole 22) and the box side cable insertion hole (for example, the box side cable insertion hole 23 in the embodiment described later) are respectively formed, and the electrical cable laid on the lower surface side of the vehicle body floor (For example, a motor power cable 17 and a compressor in an embodiment described later) The end portion of the power cable 18) is in a vehicle that is inserted into the vehicle body side cable insertion hole and the box side cable insertion hole and is wired and connected in the electrical box, and a grommet is provided between the electrical cable and each cable insertion hole. (For example, in a sealing structure of a cable insertion portion sealed by a grommet 26 in an embodiment described later) A cylindrical cable holding portion (for example, described later) that holds an electrical cable in a penetrating state in a grommet attached to a vehicle floor. An annular first seal portion formed integrally with one end side of the tubular cable holding portion and in close contact with the peripheral edge portion of the vehicle body side cable insertion hole on the surface on the vehicle body floor side. (For example, the first seal portion 33 in the embodiment described later) and the first sheet so as to surround the cable holding portion. Raised annularly from the radially inner side position of the part, through the vehicle side cable insertion hole, the tip, Ru with the elastic is closely to the peripheral portion of the box side cable insertion hole of the vehicle body floor side surface of the electrical box A second seal portion (for example, a second seal portion 34 in an embodiment described later) is provided.

  Thereby, the grommet is attached to the vehicle body floor in a state where the electric cable is held by the cable holding portion and the first seal portion is in close contact with the peripheral edge portion of the vehicle body side cable insertion hole. At this time, the annular second seal portion penetrating the vehicle body side cable insertion hole is in close contact with the peripheral portion of the box side cable insertion hole from the vehicle body floor side. Since the second seal portion is elastically brought into close contact with the vehicle body floor side, it is not necessary to install a grommet in the box side cable insertion hole, and the positional error of the electrical box with respect to the vehicle body floor is also absorbed by the elasticity of the second seal portion. It becomes possible to do. Accordingly, the electrical cable is maintained in a sealed state by a single grommet with respect to the peripheral portions of the vehicle body side cable insertion hole and the box side cable insertion hole.

  The invention according to claim 2 is the invention according to claim 1, wherein a plurality of through holes (for example, through holes 30a to 30a in embodiments described later) are inserted into the cable holding portion, respectively. 30c, 31a to 31c), and holding lips (for example, holding lips 35a to 35c and 36a to 36c in the embodiments described later) are formed adjacent to the inner peripheral surface of each through hole. The formation positions of the holding lips between the through holes to be offset are offset in the axial direction.

  In this case, a plurality of electrical cables are supported by the through holes of the cable holding part via the holding lips, but the positions of the holding lips formed between adjacent through holes are offset in the axial direction. Swelling of the through-hole peripheral wall in the radial direction outside that occurs when the electrical cable is inserted inside does not occur at the adjacent position, and as a result, suppresses the radial outward bulge of the cable holding portion in the state of holding the electrical cable It becomes possible.

  According to this invention, the grommet holding the electrical cable in the cable holding portion is attached to the vehicle body floor so that the vehicle body side cable insertion hole is sealed by the first seal portion, and the vehicle body side cable insertion hole is penetrated in that state. Since the annular second seal portion is in close contact with the peripheral portion of the box side cable insertion hole from the vehicle body floor side, the electrical cable is connected to each peripheral portion of the vehicle body side cable insertion hole and the box side cable insertion hole by a single grommet. On the other hand, it can be easily and reliably maintained in a sealed state. Therefore, according to the present invention, it is possible to facilitate the assembly and reduce the cost.

  According to the invention of claim 2, since the holding lip formed in each through hole of the cable holding portion is set to be offset in the axial direction between adjacent through holes, the electric cable is held. Swelling of the cable holding portion in the radial direction in the state can be suppressed, and the diameter of the cable holding portion can be reduced, and further, the diameter of the vehicle body side cable insertion hole and the box side cable insertion hole can be reduced.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the directions such as front, rear, left and right in the following description are the same as those in the vehicle unless otherwise specified. In the figure, an arrow FR indicates the front of the vehicle, and an arrow LH points to the left of the vehicle.

  1 and 2, reference numeral 1 denotes a so-called parallel type hybrid vehicle. An engine room 2, a motor generator 4 (motor), and an automatic transmission 5 are provided in series in the engine room 2 at the front of the body of the hybrid vehicle, and a power unit 6 is configured by these. The motor generator 4 is constituted by a three-phase DC brushless motor. The power of the motor generator 4 and the engine 3 is transmitted to the front wheels 7 as driving wheels via an automatic transmission 5.

  Also, in this hybrid vehicle, when driving force is transmitted from the front wheels 7 to the motor generator 4 during deceleration or the like, the motor generator 4 functions as a generator and recovers energy as so-called regenerative braking force. The collected electrical energy is charged into the battery 50 via the motor inverter 8 (electric equipment).

  The power unit 6 is provided with an air conditioner (air conditioner) compressor 9. The compressor 9 is driven by a motor (not shown). This motor is a three-phase motor, and is supplied with electric power from the compressor inverter 10 (electric equipment) during driving.

  A vehicle compartment 13 in which a front seat 11 and a rear seat 12 are disposed is provided behind the engine room 2, and a box-type electrical box is provided in a space between the trunk room 14 on the rear side of the vehicle compartment and the seat back of the rear seat 12. 16 is arranged. The electrical box 16 is formed in a substantially rectangular parallelepiped shape, and a battery 50 is accommodated therein, and an electrical unit 15 in which the motor inverter 8, the compressor inverter 10, and other electrical equipment are collectively arranged is accommodated. The motor inverter 8 and the compressor inverter 10 obtain a direct current from the battery 50, convert the direct current into a three-phase alternating current, and supply the current to the motor generator 4 and the air conditioner compressor 9 to supply them. To drive. The electrical box 16 is attached to a body frame (not shown) at the back of the rear seat 12, and a gap is provided between the electrical box 16 and the body floor 19.

  As shown in FIG. 2, the motor generator 4 and the motor inverter 8 are connected by three-phase motor power cables (electrical cables) 17U, 17V, and 17W. Similarly, the air conditioner compressor 9 and the compressor inverter 10 are They are connected by three-phase compressor power cables (electrical cables) 18U, 18V, 18W. Hereinafter, when it is not necessary to distinguish between the phases, the motor power cable is denoted by reference numeral 17, and the compressor power cable is denoted by reference numeral 18.

  As shown in FIG. 1, each of the power cables 17 and 18 is laid from the engine room 2 through the lower surface of the vehicle body floor 19, passes through the vehicle body floor 19 and the electrical box 16 at the rear surface side position of the rear seat 12, and 16 are connected to a motor inverter 8 and a compressor inverter 10 respectively. An intermediate region of the power cables 17 and 18 arranged on the lower surface side of the vehicle body floor 19 is integrated and covered with a metal protection tube 21. As shown in FIG. 4, a vehicle body side cable insertion hole 22 and a box side cable insertion hole 23 into which ends of the power cables 17 and 18 are inserted are formed in the vehicle body floor 19 and the electrical box 16, respectively. The box side cable insertion hole 23 is formed to have a smaller diameter than the vehicle body side cable insertion hole 22 and is positioned immediately above the vehicle body side cable insertion hole 22 in a state in which the electrical box 16 is attached to the vehicle body. In addition, a shaft portion 25 of a flange-shaped mounting bracket 24 is fitted and fixed to the end portion of the protective tube 21 surrounding the power cables 17 and 18, and the power cables 17 and 18 are connected to the shaft portion 25 of the bracket 24. The end is protruding. A grommet 26 made of an elastic member such as a rubber material is held on the upper surface side of the mounting bracket 24.

  As shown in FIGS. 4 to 8, the grommet 26 has a base portion 28 arranged in a fitted state in a recessed portion 27 of the mounting bracket 24 formed in a substantially elliptical disk shape. A cable holding portion 29 that holds the power cables 17 and 18 in a penetrating state is provided at the position. The cable holding portion 29 is formed so as to be raised at a set height with respect to the upper surface of the base portion 28, and a plurality of through holes 30 a to 30 c and 31 a to 31 c for inserting the power cables 17 and 18 are mutually connected. It is formed so as to be dense. The cable holding portion 29 will be described in detail later.

  As shown in FIG. 4, the bracket 24 is coupled to the lower surface side of the vehicle body floor 19 by bolts and nuts 32 with the grommet 26 sandwiched between the bracket 24 and the upper surface of the base portion 28 of the grommet 26. A first seal portion 33 composed of two annular protrusions is formed on the side outer peripheral edge, and the peripheral portion of the vehicle body side cable insertion hole 22 is sealed by the first seal portion 33. Further, a bellows-like second seal portion 34 is integrally formed so as to surround the cable holding portion 29 at a position radially inward of the upper surface of the base portion 28 relative to the first seal portion 33. The second seal portion 34 protrudes upward through the vehicle body side cable insertion hole 22 in a state where the grommet 26 is attached to the vehicle body floor 19, and as shown in FIG. 3 and FIG. ) Of the box-side cable insertion hole 22 of FIG. The second seal portion 34 is formed in a bellows shape, and elastically follows the lower surface of the electrical box 16 so as to flexibly follow. Therefore, an error in the height direction between the vehicle body floor 19 and the electrical box 16, or the box side cable insertion hole 23. Even if there is a shift in position, these can be reliably absorbed.

  Here, since a high voltage is applied to the motor power cable 17, the diameter of the motor power cable 17 is large, and the motor power cable 17 has a larger diameter than the compressor power cable 18 having a relatively low applied voltage. The cable holding portion 29 of the grommet 26 is formed with three through holes 30a to 30c and 31a to 31c for the motor and the compressor as shown in FIG. An inner diameter corresponding to the outer diameter is formed. The large-diameter through holes 30a, 30b, and 30c for the motor are densely arranged around the axis of the cable holding portion 29 so as to form the tops of equilateral triangles, and the small-diameter through-holes 31a, 30a for the compressor are arranged. 31b and 31c are arrange | positioned so that these may make a triangular top part in each outer clearance gap between the through-holes 30b and 30c, 30a and 30c, and 30a and 30b among the cable holding parts 29. . Accordingly, the two types of through holes 30 a to 30 c and 31 a to 31 c having different diameters are densely arranged near the axis of the cable holding portion 29 in this way. Since the three large-diameter through holes 35a to 35c are densely arranged on the axial center side, all of them are adjacent to each other.

  Further, on the inner peripheral surfaces of the through holes 30a to 30c and 31a to 31c, as shown in FIGS. 4, 7, and 8, annular power cables 17 and 18 are fitted and held in a sealed state. The holding lips 35a to 35c and 36a to 36c are respectively formed. The holding lips 35a to 35c formed in the large-diameter through holes 30a to 30c are offset from each other in the axial direction, and similarly the holding lips 36a to 36c formed in the small-diameter through holes 31a to 31c are also provided. They are offset from each other in the axial direction. In the case of this embodiment, as shown in FIG. 8 (E), the holding lips 35a, 36a in the through holes 30a, 31a are arranged at an intermediate height (approximately the intermediate position in the axial direction of the cable holding portion 29). On the other hand, the holding lips 35b and 36b in the through holes 30b and 31b are arranged at the upper position as shown in FIG. 8F, and the holding lips 35c and 36c in the through holes 30c and 31c are arranged in FIG. As shown in FIG. Therefore, in the case of the cable holding portion 29, the holding lips (35a to 35c) in the adjacent through holes (35a to 35c, 36a to 36c) are all offset in the axial direction.

As described above, in this seal structure, the power cables 17 and 18 are connected to the vehicle body side cable insertion hole 22 only by attaching the single grommet 26 holding the power cables 17 and 18 to the vehicle body floor 19 via the bracket 24. The box-side cable insertion hole 23 can be easily and surely sealed. That is, when the grommet 26 holding the power cables 17 and 18 is attached to the vehicle body floor 19 together with the bracket 24, the peripheral portion of the vehicle body side cable insertion hole 22 is sealed by the first seal portion 33 of the grommet 26, and the base portion The second seal portion 34 rising in an annular shape from the upper portion 28 is in close contact with the peripheral portion of the box-side cable insertion hole 23 on the lower surface of the electrical box 16, thereby sealing the peripheral portion of the box-side cable insertion hole 23.
Note that the second seal portion 34 of the grommet 26 only abuts against the electrical box 16 from the lower surface side with elasticity, but the seal at this portion does not release the intake pressure by the cooling fan in the electrical box 16. Since positive pressure does not act from the inside of the electrical box 16, the sealed state can be reliably maintained by the second seal portion 34 during operation of the cooling fan.

  Therefore, when this seal structure is adopted, both the insertion holes 22 and 23 can be sealed with a single grommet 26, so that the cost can be reduced and the assembly can be facilitated by reducing the number of parts.

  In the case of this embodiment, the second seal portion 34 that is in close contact with the electrical equipment box 16 from the lower surface side has a bellows structure that can allow relatively large elastic deformation in the axial direction and the radial direction. Even if there is a slight misalignment between the floor 19 and the electrical box 16, the bellows structure can flexibly absorb the misalignment, and the peripheral edge of the box side cable insertion hole 23 can be reliably maintained in a sealed state.

  The cable holding portion 29 of the grommet 26 that holds the power cables 17 and 18 in a penetrating state has holding lips (35a to 35c, 36a to 36c) in adjacent through holes (30a to 30c, 31a to 31c). Since the power cables 17 and 18 are fitted in the through holes 35a to 35c and 36a to 36c, the radially outward bulge of the peripheral wall of the through hole is formed at the adjacent position. No longer occurs. For this reason, the bulge in the radial direction by the holding lips 35a to 35c and 36a to 36c is absorbed by the elasticity inside the cable holding portion 29, and a part of the axial direction of the cable holding portion 29 is greatly bulged and deformed outward in the radial direction. There is no problem. Therefore, it is possible to reduce the diameter of the cable holding portion 29 and to reduce the diameter of the box side cable insertion hole 23 and the vehicle body side cable insertion hole 22.

  In addition, this invention is not limited to the said embodiment, A various design change is possible in the range which does not deviate from the summary. For example, in the above-described embodiment, the case where the electrical cable passing through the vehicle body floor and the electrical box is a power cable for a motor and a compressor is described. However, the electrical cable is not limited to a power cable for a motor and a compressor. It may be a power cable of another device, a signal cable for control, or the like.

BRIEF DESCRIPTION OF THE DRAWINGS The structure explanatory drawing which showed one Embodiment of this invention and looked at the vehicle from the side surface side. The structure explanatory view which shows the same embodiment and looked at the vehicle from the upper surface side. The perspective view which shows the same embodiment and looked at the cable insertion part corresponded to the A section of FIG. 1 from the inner side of the electrical equipment box. Sectional drawing corresponding to the BB cross section of FIG. 3 which shows the same embodiment. The perspective view of the cable insertion part which shows the same embodiment and which partially fractured the electrical equipment box of FIG. The top view of the state which showed the same embodiment and attached the grommet to the bracket. Sectional drawing corresponding to CC cross section of FIG. 6 which shows the same embodiment. The figure which shows the same embodiment and combined with sectional drawing (D)-(F) corresponding to the DD cross section of FIG. 6, EE cross section, and FF cross section, respectively. Sectional drawing of the cable insertion part which shows the prior art.

Explanation of symbols

8 ... Motor inverter (electric equipment)
10 ... Electric invar for compressor (electric equipment)
16 ... Electrical box 17 ... Motor power cable (electrical cable)
18 ... Compressor power cable (electrical cable)
DESCRIPTION OF SYMBOLS 19 ... Vehicle body floor 22 ... Vehicle body side cable insertion hole 23 ... Box side cable insertion hole 26 ... Grommet 29 ... Cable holding part 30a-30c, 31a-31c ... Through-hole 33 ... 1st seal part 34 ... 2nd seal part 35a- 35c, 36a to 36c ... holding lip 50 ... battery (electric equipment)

Claims (2)

An electrical box that accommodates electrical equipment is disposed above the body floor with a gap, and a body-side cable insertion hole and a box-side cable insertion hole are formed in the body floor and the electrical box, respectively, and on the lower surface side of the body floor. The end of the laid electrical cable is in the vehicle that is inserted into the vehicle body side cable insertion hole and the box side cable insertion hole and wired and connected in the electrical box,
In the seal structure of the cable insertion part where the gap between the electrical cable and each cable insertion hole is sealed by a grommet,
To the grommet attached to the car body floor,
A cylindrical cable holder for holding the electrical cable in a penetrating state;
An annular first seal portion that is integrally formed on one end side of the cylindrical cable holding portion and is in close contact with a peripheral edge portion of the vehicle body side cable insertion hole on the surface of the vehicle body floor side ;
It raised annularly from the radially inner side position of the first sealing portion so as to surround the cable holding portion, through the vehicle side cable insertion hole, the tip box body floor side surface of the electrical box a second seal portion Ru in close contact with the elastic peripheral portion of the side cable insertion hole,
A seal structure for a cable insertion portion, characterized by comprising   The cable holding portion is provided with a plurality of through holes into which a plurality of electric cables are respectively inserted, and a holding lip for holding the electric cables is formed on the inner peripheral surface of each through hole, and the adjacent through holes are formed with the above-mentioned 2. The cable insertion portion sealing structure according to claim 1, wherein the formation position of the holding lip is offset in the axial direction.

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