JP7716041B2 - Case fixing structure - Google Patents

Description

The present invention relates to a structure for fixing a case housing an electronic device to a structure, and more specifically to a case fixing structure that functions to protect the electronic device from vibrations of the structure.

A conventional case fixing structure is described in Patent Document 1. The fixing structure described in Patent Document 1 includes a connecting member fixed to a vehicle side member and a case protrusion facing the upper surface of the connecting member. The case houses an inverter. Furthermore, an inner cylindrical portion, a cylindrical buffer member, and an outer cylindrical portion are coaxially arranged on the upper surface of the connecting member, from the center.

The fixing structure secures the protruding portion of the case to the connecting member by fitting a hole formed in the protruding portion of the case onto the outer periphery of the outer cylindrical portion, then passing a bolt through a washer into the inside of the inner cylindrical portion and into the connecting member, and then screwing a nut onto the tip of the bolt protruding from the underside of the connecting member. This fixing structure uses a buffer member interposed between the connecting member and the protruding portion to absorb vibrations generated on the side member side, protecting the inverter housed in the case from vibration.

Patent No. 5527406

However, the fixing structure of the conventional case described above is a triple structure with a soft, cylindrical cushioning member sandwiched between a hard outer and inner cylindrical portion. This results in a complex structure, cumbersome assembly work, and high manufacturing costs. Therefore, solving these problems was an issue.

The present invention was developed in response to the above-mentioned conventional problems, and aims to provide a case fixing structure that simplifies the structure and assembly work and reduces manufacturing costs.

The case fixing structure according to the present invention is a structure for fixing a case housing an electronic device to a structure. In this case fixing structure, the structure and the case have connecting portions facing each other at a predetermined distance. One of the connecting portions of the structure or the case includes a mounting hole penetrating the thickness direction thereof, a tubular buffer member attached to the mounting hole, and a tubular collar attached to the inner hole of the buffer member. The case fixing structure includes a bolt inserted through the inner hole of the collar and threadedly fastened to a nut provided on the other connecting portion, and the buffer member is interposed between the one connecting portion and the collar . The structure and the case are mounted on a vehicle, and the pin and receiving hole combination is located in a portion other than the surface facing the vehicle interior wall .

In the case fixing structure of this invention, the cylindrical buffer member is made of a soft material such as rubber, and the cylindrical collar is made of a hard material such as metal. Therefore, at the connection point between either the structure or the case, the buffer member can be pre-attached to the mounting hole and the collar inserted into the inner hole; no external cylindrical member for inserting the buffer member is required. This simplifies the structure and assembly process of the case fixing structure, and reduces manufacturing costs.

1 is a cross-sectional view showing a first embodiment of a case fixing structure according to the present invention; FIG. 2 is a plan view illustrating the arrangement of the case in the vehicle.

First Embodiment
Fig. 1 is a diagram showing a first embodiment of a case fixing structure according to the present invention. The illustrated case fixing structure is a structure for fixing a case housing an electronic device to a structure. This embodiment illustrates a case in which a case C housing an inverter (electronic device) IN is fixed to the top of a motor (structural body) M adjacent to an engine E in an engine compartment of a vehicle, as shown in Fig. 2. The case C has a flat cover K that closes the open upper portion, and a gasket G is interposed between the case C and the cover K.

The fixing structure of the case C is such that the motor M and case C have connecting portions 1, 2 that face each other at a predetermined distance, and one of the connecting portions has a mounting hole 3 that is open in the thickness direction, a cylindrical buffer member 4 that is attached to the mounting hole 3 and penetrates it, and a cylindrical collar 5 that is attached to the inner hole 4H of the buffer member 4. The fixing structure has a bolt 6 inserted through the inner hole 5H of the collar 5 and threaded into a nut portion 7 provided on the other connecting portion, and the buffer member 4 is interposed between one connecting portion and the collar 5.

In this embodiment, the fixing structure has connecting portions 1 and 2 of the motor M and case C formed in a plate shape and facing each other vertically, with connecting portion 2 of case C on the upper side and connecting portion 1 of motor M on the lower side. Connecting portion 2 of case C is an extension portion integrated with cover K. Connecting portion 1 of motor M is an extension portion integrated with the housing of motor M, etc.

The fixing structure includes the mounting hole 3, buffer member 4, and collar 5 at the connecting portion 2 of the case C, which is one of the connecting portions. The fixing structure also includes a nut portion 7 at the other connecting portion 1, into which the tip of the bolt 6 threads. Note that the fixing structure can also be configured in the opposite way to the illustrated example, with the mounting hole 3, buffer member 4, and collar 5 provided at the connecting portion 1 of the motor M, and the nut portion 7 at the connecting portion 2 of the case C into which the bolt 6 threads.

The buffer member 4 is a relatively soft material made of rubber or similar material, and has a small-diameter section 4A, located axially toward the upper end of its central section, with a width equivalent to the thickness of the connecting section 2, and an upper large-diameter section 4B and a lower large-diameter section 4C on either side of it.

The collar 5 is a relatively hard member made of metal, plastic, or the like. It has an outer diameter equivalent to the inner diameter of the inner hole 4H of the buffer member 4, a length equivalent to the overall length of the buffer member 4, and an outward flange portion 5F at its upper end that abuts against the upper end surface of the buffer member 4. The inner diameter of the inner hole 5H of the collar 5 is clearly larger than the diameter of the bolt 6.

The fixing structure can also be configured to include at least one of a washer 8 attached to the head of the bolt 6 and abutting the end face of the buffer member 4, and a flange 5F formed on the end of the collar 5 and abutting the end face of the buffer member 4. In this embodiment, both the washer 8 and flange 5F are provided, and the flange 5F, which is the lower side of the washer 8, abuts the end face of the buffer member 4.

Furthermore, in the above-mentioned fixing structure, one of the connecting parts, connecting part 2 of case C, is provided with a pin 10 that passes through a receiving hole 9 formed in the other connecting part 1. There is an appropriate clearance between the pin 10 and the receiving hole 9, allowing for axial separation but substantially restricting radial movement. Note that the above-mentioned fixing structure may be configured so that the receiving hole 9 is provided in one connecting part 2 and the pin 10 is provided in the other connecting part 1, as opposed to the illustrated example. However, when both connecting parts 1, 2 are arranged one above the other as in the illustrated example, it is more desirable to provide the receiving hole 9 in the other connecting part 1, which is the lower part.

Furthermore, the above-mentioned fixing structure is configured such that the protruding dimension L2 of the tip portion of the pin 10 protruding from the receiving hole 9 is greater than the axial length dimension L1 of the large diameter portion, i.e., the upper large diameter portion 4B, located between the head of the bolt 6 and one of the connecting portions 2 (L1 < L2).

Furthermore, the above-mentioned fixing structure has pin 10 and receiving hole 9 combinations (A) arranged in multiple locations on the case C. In this case, since the fixing structure of this embodiment is intended for the motor M and case C to be mounted on a vehicle, it is more desirable to arrange the pin 10 and receiving hole 9 combinations in a location other than the surface facing the vehicle's inner wall W.

In Figure 2, the left side is the front of the vehicle, and the front, rear, and one side of the motor M are surrounded by the body wall W. Therefore, in this embodiment, as shown in Figure 2, the combination (A) of the pin 10 and receiving hole 9 is located in two places on the engine E side, which is the part other than the surface facing the body wall W. Note that the fixing structure, the combination (B) of the mounting hole 3, buffer member 4, collar 5, bolt 6, and nut portion 7, can also be located in multiple places (four places in the figure) as shown in Figure 2.

The fixing structure of the case with the above configuration has a cylindrical buffer member 4 made of a soft material such as rubber, and a cylindrical collar 5 made of a hard material such as metal. When fixing the case C to the motor M, the buffer member 4 is first attached to the mounting hole 3 in the connecting portion 2 of the case C. At this time, the buffer member 4 is elastically deformed and inserted into the mounting hole 3, so that the small diameter portion 4A engages with the mounting hole 3 and the upper large diameter portion 4B and lower large diameter portion 4C protrude upward and downward, and the entire member is attached to the mounting hole 3 in a penetrating state. Therefore, there is no need to worry about the buffer member 4 accidentally coming off the mounting hole 3.

Then, the above-mentioned fixing structure can be achieved by simply inserting the collar 5 into the inner hole 4H of the buffer member 4. This eliminates the need for an outer tube and simplifies assembly, compared to, for example, a conventional triple structure in which a cylindrical soft buffer member is sandwiched between a hard outer tube and an inner tube.

Next, the case C is positioned by inserting the pin 10 into the receiving hole 9 of the connecting portion 1 of the motor M. At this time, the fixing structure is positioned so that the buffer member 4 and collar 5 are coaxially aligned with the nut portion 7, with the lower ends of the buffer member 4 and collar 5 abutting the upper surface of the connecting portion 1 and the tip of the pin 10 protruding below the receiving hole 9. The fixing structure then completes by inserting the bolt 6 into the inner hole 5H of the collar 5 via the washer 8 and screwing the bolt 6 into the nut portion 7, completing the fixing of the case C.

In this way, the above-mentioned fixing structure has a buffer member 4 interposed between the connecting portion 1 and the collar 5 in the case C, which absorbs vibrations from the engine E and motor M, protecting the inverter IN housed in the case C from vibration. As is clear from the assembly method described above, the above-mentioned fixing structure simplifies the structure and assembly work, while also reducing manufacturing costs.

Furthermore, the above-mentioned fixing structure has one connecting portion (connecting portion 2 of case C) equipped with a pin 10 that passes through a receiving hole 9 formed in the other connecting portion (connecting portion 1 of motor M), making it easier to position case C and contributing to further simplification of assembly work. Furthermore, when the above-mentioned fixing structure is mounted on a vehicle and subjected to an external force such as a collision, the engagement between receiving hole 9 and pin 10 prevents case C from shifting, thereby providing high-voltage protection for the electronic device (inverter IN).

Furthermore, in the above-mentioned fixing structure, the buffer member 4 has a small diameter portion 4A, an upper large diameter portion 4B, and a lower large diameter portion 4C, and is equipped with a washer 8 attached to the head of the bolt 6 and a flange portion 5F formed on the end of the collar 5, with the flange portion 5F abutting against the upper end surface of the buffer member 4. As a result, the above-mentioned fixing structure can easily and reliably fix the buffer member 4 to the mounting hole 3 in the case C, and the washer 8 and flange portion 5F restrain the buffer member 4, thereby maintaining excellent vibration absorption function.

Furthermore, in the above-described fixing structure, the protruding dimension L2 of the tip portion of the pin 10 protruding from the receiving hole 9 is greater than the axial length dimension L1 of the upper large diameter portion 4B located between the head of the bolt 6 and the connecting portion 1. As a result, the above-described fixing structure reliably maintains the engagement between the receiving hole 9 and the pin 10, even if the upper large diameter portion 4B is compressed due to vibration in the axial direction of the buffer member 4 (the vertical direction in this embodiment), thereby increasing the axial holding force of the buffer member 4.

Furthermore, the above-mentioned fixing structure has the connecting portion 1 of the case C and the connecting portion 2 of the motor M arranged opposite each other vertically, with the receiving hole 9 provided in the lower connecting portion 1 of the motor M. This prevents water from directly contacting the receiving hole 9 during rain or when washing the car, and prevents clogging of the hole due to corrosion caused by moisture, etc.

Furthermore, the above-mentioned fixing structure allows the pin 10 and receiving hole 9 combination (B) to be positioned at multiple locations on the case C, making it possible to position the case C easily and with high precision. Moreover, when the case C is mounted on a vehicle and subjected to an external force such as a collision, it can more reliably prevent displacement of the case C, improving the high-voltage protection function of the electronic device (inverter IN).

Furthermore, the above-mentioned fixing structure is one in which the structural body (motor M) and case C are mounted on a vehicle, and the combination (A) of pin 10 and receiving hole 9 is positioned in a portion other than the surface facing the vehicle's inner body wall W. As a result, the above-mentioned fixing structure minimizes damage to the pin 10 and receiving hole 9 due to deformation of the inner body wall W in the event of an external force such as a collision, and effectively maintains the high-voltage protection function of the electronic device (inverter IN).

The case fixing structure according to the present invention is not limited to the configuration of the above embodiment, and can be modified as appropriate without departing from the spirit of the present invention. It is applicable not only to vehicle installations, but also to fixing structures between various structures and cases housing electronic devices.

C Case IN Inverter (electronic device)
M Motor (structure)
W: Car body wall 1: Motor connection part (other connection part)
2 Case connection part (one connection part)
3 Mounting hole 4 Buffer member 4A Small diameter portion 4B Upper large diameter portion 4C Lower large diameter portion 4H Inner hole 5 Collar 5F Flange portion 5H Inner hole 6 Bolt 7 Nut portion 8 Washer 9 Receiving hole 10 Pin

Claims (5)

A structure for fixing a case containing an electronic device to a structural body,
the structure and the case have connecting portions that face each other at a predetermined interval,
a connecting portion of either the structure or the case includes a mounting hole that is open in its thickness direction, a cylindrical buffer member that is attached to the mounting hole in a penetrating state, and a cylindrical collar that is attached to an inner hole of the buffer member;
a bolt inserted into an inner hole of the collar is screwed into a nut provided on the other connecting portion, and the buffer member is interposed between the one connecting portion and the collar ,
the one connecting portion has a pin that passes through a receiving hole formed in the other connecting portion,
The structure and the case are mounted on a vehicle,
A case fixing structure characterized in that the combination of the pin and the receiving hole is arranged in a portion other than the surface facing the inner wall of the vehicle . the buffer member has, in an axial direction, a small-diameter portion at an intermediate portion thereof, the small-diameter portion having a width corresponding to the thickness of the one connecting portion, and large-diameter portions on both sides of the small-diameter portion;
2. The case fixing structure according to claim 1, further comprising at least one of a washer attached to the head of the bolt and abutting the end face of the buffer member, and a flange portion formed at the end of the collar and abutting the end face of the buffer member. 3. The case fixing structure according to claim 2, characterized in that the protruding dimension of the tip portion of the pin protruding from the receiving hole is greater than the axial length dimension of the large diameter portion interposed between the head of the bolt and one of the connecting portions. The one connecting portion and the other connecting portion are arranged to face each other vertically,
4. The case fixing structure according to claim 1 , wherein the lower connecting portion has the receiving hole. 5. The case fixing structure according to claim 1 , wherein the combination of the pin and the receiving hole is arranged at a plurality of locations on the case.