JPH06286648A - Car body structure for automobile equipped with frame - Google Patents

Abstract

PURPOSE:To reduce the vibration transmission to the inside of a cabin formation part and suppress the vibration of a rigid body in the cabin formation part by devising each of the rigidity or the mass distribution of a car body part and a frame member. CONSTITUTION:Each rigidity or mass of the front side part 12F and the rear side part 12R of a frame member 12 having the suspension installation parts 22 and 28 is set larger than that of the intermediate part 12M positioned between both the parts. While, a car body part 11 is constituted of the front part 11F, rear part 11R, and a cabin formation part 13 positioned between both the parts, and the cabin formation part is formed independently from the front part and rear part, and the lower side is supported only by the intermediate part, and the mount members 50A and 50B on the front side and rear side of the cabin formation part are arranged over the position of the center of gravity of the cabin formation part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle body structure for an automobile with a frame, in which a vehicle body body including a cabin forming portion is supported by a frame member and a suspension mounting portion is provided on the frame member.

[0002]

2. Description of the Related Art Conventionally, as a vehicle body structure of an automobile, a so-called frame-attached type generally provided with a vehicle body portion including a cabin forming portion and a frame member for supporting the vehicle body portion from its lower side is generally good. Are known. Such a frame-equipped vehicle body, for example, as disclosed in Japanese Utility Model Publication No. 3-3100, combines side members formed by closed cross-section members extending in the vehicle front-rear direction and cross members extending in the vehicle width direction. A frame member that forms the skeleton of the lower part of the vehicle body is formed, and the vehicle body body is fixed to this frame member.

When a vehicle body structure with a frame composed of a frame member and a vehicle body is adopted in this way, for example, the partial structure of the frame member, the area of the closed cross section of the closed cross section member constituting the frame member, By changing the partial structure of the car body and the cross-sectional area of the members that make up the car body, the vibration transmission characteristics of each part of the car body can be changed relatively easily, and the entire car body is integrally formed. The vibration transmission state in the vehicle body can be controlled relatively easily as compared with the so-called monocoque type in which the stress outer skin structure is adopted. However, in a conventional vehicle body with a frame, in order to suppress the uncomfortable vibration transmitted to the occupant in the cabin forming portion included in the vehicle body portion, such a change in the vibration transmission characteristic of each portion of the vehicle body is positively suppressed. I couldn't find anything that caused it.

Therefore, the applicant of the present application has filed Japanese Patent Application No. 4-179.
In No. 557, the rigidity and weight of the front portion and the rear portion of the frame member to which the suspension attachment portions are respectively provided are set to be larger than those of the intermediate portion located between the front portion and the rear portion. The frame structure and the cabin forming portion are set to have rigidity or weight larger than those of the vehicle body main body portion before and after the frame structure portion, and the cabin forming portion is arranged at a position corresponding to the intermediate portion of the frame member. The body structure of a car with a frame was proposed.

By adopting such a configuration, when vibration is input to the vehicle body through the suspension mechanism, the front portion and the rear portion of the frame member are portions that are less likely to generate vibration, and the intermediate portion is It becomes a portion that easily causes vibration, and the energy of the input vibration is appropriately dispersed over the entire frame member, and the vibration transmitted from the frame member to the vehicle body portion is effectively suppressed. Further, when vibration is transmitted from the frame member to the vehicle body portion, the cabin forming portion of the vehicle body portion is less likely to vibrate, and the front and rear portions of the cabin forming portion are likely to vibrate. Therefore, the transmission of vibration to the cabin forming portion is effectively reduced. Therefore, as compared with the case where the rigidity or weight of the frame member is made uniform over the entire body, or the rigidity or weight of the vehicle body portion is made uniform over the entire body, Unpleasant vibration and noise transmitted to an occupant in the cabin forming portion of the vehicle body portion due to vibration or the like are effectively suppressed.

[0006]

By the way, when the rigidity or the weight distribution of the frame member and the body part of the vehicle body is set as described above, the method of distribution is made more extreme, and the body forming part of the cabin forming part is By making the distribution to the front and rear parts as small as possible, and making the distribution to the front and rear parts of the frame member as large as possible,
It can be considered to further effectively suppress the transmission of vibration into the cabin forming portion.

However, if the rigidity or weight distribution to the front and rear portions of the cabin forming portion is made too small as described above, the front and rear support of the cabin forming portion becomes insufficient, and the cabin forming portion itself becomes There is a problem in that it is easily affected by pitching, rolling, bouncing, and the like, and rigid body vibration easily occurs in the entire cabin forming portion.

Therefore, according to the present invention, by further devising the rigidity / mass distribution of the vehicle body and the frame member, it is possible to further reduce the vibration transmission into the cabin forming portion, and in this case, the cabin forming portion. It is an object of the present invention to provide a vehicle body structure of an automobile with a frame capable of suppressing the rigid body vibration.

[0009]

For this reason, the first invention of the present application is provided with a frame including a vehicle body portion including a cabin forming portion, and a frame member for supporting the vehicle body portion from a lower side thereof. In a vehicle body structure of an automobile, suspension mounting portions are provided on each of a front side portion and a rear side portion of the frame member, and the front side portion and the rear side portion are different from the front side portion in terms of at least one of rigidity and mass. While being set larger than the intermediate portion located between the rear side portion, the vehicle body portion is composed of a front portion, a rear portion, and a cabin forming portion located between these portions, The cabin portion is formed separately from the front portion and the rear portion, and the lower side thereof is supported only by the intermediate portion of the frame member. Is obtained is characterized in that there.

A second invention of the present application is the vehicle body structure for an automobile with a frame according to the first invention, wherein mount members are respectively arranged between the cabin forming portion and the front and rear portions. The mount members are arranged above the center of gravity of the cabin forming portion.

Further, a third invention of the present application is, in the vehicle body structure for an automobile with a frame according to the first or second invention, arranged between the cabin forming portion and the front and rear portions, respectively. Each of the mounting members is characterized in that its damping characteristic is set higher than the damping characteristic of the mounting member arranged between the cabin forming portion and the frame member.

Further, a fourth invention of the present application is, in the vehicle body structure of the automobile with a frame according to the first or second invention, arranged between the cabin forming portion and the front and rear portions, respectively. The vertical and horizontal spring constants of each of the mounted mount members are the same as the spring constants of the mount member in the front-rear direction and in all directions of the mount member arranged between the cabin forming portion and the frame member. It is characterized by being set higher than the spring constant.

[0013]

According to the first aspect of the present invention, since the cabin forming portion is formed separately from the front portion and the rear portion, the front portion and the rear portion of the vehicle body portion are respectively formed of the frame member. It can be effectively utilized as a member for increasing at least one of rigidity and mass with respect to the front side portion and the rear side portion. That is, a frame structure in which the front side portion and the rear side portion of the frame member are set larger in at least one of rigidity and mass thereof than an intermediate portion positioned between the front side portion and the rear side portion, and , The cabin forming portion is set to have a larger rigidity and / or mass than the front and rear vehicle body portions, and the cabin forming portion is arranged at a position corresponding to the intermediate portion of the frame member. As a result, the vehicle body structure can be made extremely limited, and it becomes possible to further reduce the vibration and noise input to the cabin forming portion.

Further, according to the second invention of the present application, basically, the same effect as that of the first invention can be obtained. Moreover, since the mount member provided between the cabin forming portion and the front and rear portions is arranged above the center of gravity of the cabin forming portion,
It is possible to restrain the portion where the locus of movement increases when pitching or rolling acts on the cabin forming portion, and it is possible to effectively suppress rigid body vibration of the cabin forming portion.

Further, according to the third invention of the present application, basically, the same effect as that of the first or second invention can be obtained. Moreover, the damping characteristic of each mount member disposed between the cabin forming portion and the front portion and the rear portion is determined by the mount member disposed between the cabin forming portion and the frame member. Since it is set to be higher than the damping characteristic of, the vibration peak at the resonance point can be gently lowered and at the same time, the cutoff property against the vibration of the frequency above the resonance point input from the frame member side can be effectively enhanced. The comfort inside the cabin forming part can be further improved.

Further, according to the fourth invention of the present application,
Basically, the same effect as that of the first or second invention can be obtained. Moreover, the spring constants in the up-down direction and the left-right direction of the mount members disposed between the cabin forming portion and the front portion and the rear portion are determined by the spring constants in the front-rear direction of the mount member and the cabin. Since the spring constant is set higher than the spring constant in all directions of the mount member arranged between the frame and the frame member, vertical and horizontal restraint when pitching, rolling or bouncing acts on the cabin forming part. It is possible to improve the property and suppress the generation of the rigid body vibration, and it is possible to effectively absorb the high frequency vibration input from the frame member side, thereby further improving the comfort inside the cabin forming portion.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a side view schematically showing an example of a vehicle body structure of a vehicle with a frame according to this embodiment,
2 is an explanatory plan view showing the frame structure of the automobile with the frame. As shown in these drawings, in the vehicle according to the present embodiment, a vehicle body 10 includes a vehicle body portion 11 and a frame member 1 that supports the vehicle body portion 11 from below.
2 and. A cabin forming portion 13 is provided in the vehicle body portion 11, and in the present embodiment,
In the vehicle body portion 11, the cabin forming portion 13 has front and rear vehicle body front portions 11F and 11R.
It is formed as an independent cabin that is separate and independent from

As can be seen from FIG. 2, the frame member 12 includes a pair of left and right side members 14L and 14R extending in the front-rear direction of the vehicle body 10 and both side members 14L and 1L.
Cross member 1 that connects the front parts of 4R to each other
6 and 17 and cross members 18 and 19 that connect the central portions of both side members 14L and 14R to each other. The side members 14L and 14R and the cross members 16 to 19 are each made of, for example, a steel material having a closed cross-section structure. The frame member 12 includes
In the front side portion 12F corresponding to the front portion of the vehicle body 10,
Left front suspension mechanism 2 for suspending and supporting the front left wheel 20
Left front suspension mounting portion 22 to which 1 is mounted
And a right front suspension mounting portion 2 to which a right front suspension mechanism 24 that suspends and supports the right front wheel 23 is mounted.
And 5 are provided. Further, a rear left portion 12R corresponding to the rear portion of the vehicle body 10 has a left rear suspension mounting portion 28 to which a left rear suspension mechanism 27 for suspending and supporting the left rear wheel 26 is attached, and a right rear wheel 29 for suspending and supporting the right rear wheel 29. A right rear suspension mounting portion 31 to which the rear suspension mechanism 30 is mounted is provided.

The front side portion 12F of the frame member 12 provided with the left front suspension mounting portion 22 and the right front suspension mounting portion 25 is connected to the side members 14L and 14R from the lower surface side,
A front reinforcement member 32 is fixed which increases the rigidity and mass of the entire front portion. Further, in the rear side portion 12R of the frame member 12 where the left rear suspension mounting portion 28 and the right rear suspension mounting portion 31 are provided,
Both side members 14L, 14R are connected from the upper surface side, and a frame-shaped rear reinforcing member 33 that increases the rigidity and mass of the entire rear portion is fixed. By thus fixing the front reinforcing member 32 and the rear reinforcing member 33, the frame member 12 includes the front portion 12F provided with the left front suspension mounting portion 22 and the right front suspension mounting portion 25, and the left rear portion. Each of the rear portion 12R provided with the suspension mounting portion 28 and the right rear suspension mounting portion 31 has a rigidity and a mass of at least one of the rear portion 12R and the rear portion 12R.
The rigidity or mass is made larger than that of the intermediate portion 12M located between the two. Further, in particular, in the present embodiment, the front portion 11F of the vehicle body portion 11 is integrally fixed to the front portion 12F of the frame member 12, while the rear portion 11R includes the rear portion 12 of the frame member 12.
The front portion 11F and the rear portion 11R of the vehicle body portion 11 are integrally fixed to the R, and are effectively utilized as members that increase the rigidity or mass of the front portion 12F and the rear portion 12R of the frame member 12, respectively. Has been done.

The cabin forming section 13 (independent cabin section)
The lower side of the frame member 12 is supported only by the intermediate portion 12M of the frame member 12. Specifically, a plurality of side members 14L and 14R constituting the frame member 12 are arranged at portions corresponding to the intermediate portion 12M. It is supported on the frame member 12 via the mount members 50C, 50D, 50E. The cabin forming unit 13
As will be described later in detail, the front and rear portions of the upper portion of the vehicle are supported on the vehicle body front portion 11F and rear portion 11R sides via mount members 50A and 50B, respectively.
A left side sill portion 36 and a right side sill portion 37, which have a closed cross-section structure and are respectively supported by the intermediate portion 12M of the frame member 12, are disposed at the left and right lower end portions of the cabin forming portion 13. In this way, the cabin forming portion 13 is provided in front of and behind the front portion 11F and rear portion 11F.
By adopting an independent type that is separate and independent from R, the vehicle body portion 11 has an intermediate portion 12 in the frame member 12.
The cabin forming portion 13 corresponding to M has the front portion 11 with respect to at least one of its rigidity and mass.
The structure that is set to be larger than that of the F and the rear portion 11R is a limit structure.

In a vehicle equipped with a vehicle body 10 to which an example of the vehicle body structure for a vehicle with a frame according to the present invention configured as described above is applied, the left and right front wheels according to the state of the road surface while the vehicle is running. 20,23 and left and right rear wheels 2
The vibrations (vibrations from the road surface) generated in the reference numerals 6, 29 are transmitted through the left and right front suspension mechanisms 21, 24 and the left and right rear suspension mechanisms 27, 30 to the left and right front suspension mounting portions 22, 25 and the left and right rear suspension mounting portions 2.
8 and 31 are transmitted to the left and right side members 14L and 14R of the frame member 12.

The left and right side members 14L,
When the vibration from the road surface is transmitted to 14R, the front portion 12F provided with the left and right front suspension mounting portions 22 and 25 which are the vibration input portions of the frame member 12.
And the rear portion 12R provided with the left and right rear suspension mounting portions 28, 31 are provided with the front reinforcing member 32 and the rear reinforcing member 33, respectively, so that the vehicle body front portion 11F and the rear portion 11R are further integrated. As a result, the rigidity and the mass are at least one of which is maximized as compared with the intermediate portion 12M located between the front portion 12F and the rear portion 12R. Since the front side portion 12F and the rear side portion 12R of the frame member 12 are less likely to vibrate, the middle portion 12 of the frame member 12
M is more likely to generate vibration. Therefore, the vibration transmitted from the front side portion 12F and the rear side portion 12R in which the left and right front suspension mounting portions 22 and 25 and the left and right rear suspension mounting portions 28 and 31 which are the vibration input portions are respectively provided in the frame member 12, The energy will be more effectively diffused throughout the frame member 12. As a result, the vibration transmitted from the frame member 12 to the cabin forming portion 13 of the vehicle body 11 is extremely effectively reduced.

Further, in the vehicle body portion 11, the cabin forming portion 13 corresponding to the intermediate portion 12M of the frame member 12 is an independent cabin separated from the front portion 11F and the rear portion 11R. However, the structure in which at least one of the rigidity and the mass thereof is set to be larger than that of the front portion 11F and the rear portion 11R is a limit, and the structure is limited from the frame member 12 to the cabin forming portion of the vehicle body portion 11. The vibration transmitted to 13 will be reduced further. Therefore, the unpleasant vibration transmitted to the occupant in the cabin forming portion 13 of the vehicle body portion 11 is further effectively suppressed, the riding comfort felt by the occupant is improved, and the cabin forming portion 13 is made quiet. become.

The vibration suppressing effect in the vehicle body 10 to which the example of the vehicle body structure for a frame-mounted automobile according to the present invention is applied is confirmed from the result of the vibration model experiment conducted by the inventor of the present invention. . The vibration model experiment will be described below. This vibration model experiment is as shown in FIG. 4, which corresponds to the conventional vehicle body structure of a frame-equipped vehicle, as shown in FIG. 3, and the vehicle body structure of a frame-equipped vehicle according to the present invention. The vibration model MJ was prepared. The vibration model MP has a flat plate shape as a whole, and has a rectangular parallelepiped shape as a whole by a lower block 41 corresponding to a frame member formed as a member having a mass and a rigidity evenly distributed over the whole. However, the upper block 42 corresponding to the body portion of the vehicle body, which is formed to have the mass and rigidity evenly distributed over the whole, is supported through the elastic members 43 corresponding to the plurality of mount members. Configured as.

The lower block 41 and the upper block 42 are made of iron, respectively. Regarding the size and weight, the lower block 41 has a length LFP of 81 cm, a width WFP of 5 cm, a thickness TFP of 0.75 cm, and a weight. Is 2.4 kg, and the upper block 42 has a length LBP of 81 c.
m, width WBP was 5 cm, thickness TBP was 1.75 cm, and weight was 5.6 kg. Further, ten elastic members 43 were arranged between the lower block 41 and the upper block 42, and the total spring constant was set to 830 N / mm.

On the other hand, in the vibration model MJ, the lower block 45 corresponding to the frame member 12 and the upper block 46 corresponding to the vehicle body 11 are elastic members corresponding to the plurality of mount members 50A to 50E. It was constructed as supported via 47. The lower block 45 is made of iron, and both end portions 45A and 45B are made thicker and the end portion 45A is made as shown in FIG.
The central portion 45C sandwiched by the end portion 45B and the end portion 45B is formed as a thin portion, and the dimensions and weight are the length L
FJ 81cm, width WFJ 5cm, both ends 45A, 45
Each thickness TFEJ of B is 1.25 cm, central part 4
The thickness TFCJ of 5C is 0.35 cm and
Each of the both end portions 45A and 45B has a rigidity or weight greater than that of the central portion 45C.

The upper block 46 is made of iron,
As shown in FIG. 4, it is formed in a rectangular parallelepiped shape as a whole, and its size and weight are such that the length LBJ is 45.
0 cm, width WBJ is 5 cm, thickness TBCJ is 3.15 cm
Was taken. Further, the elastic member 47 is provided on the lower block 45.
Between the upper block 46 and the upper block 46, the total spring constant was 830 N / mm.

With the vibration models MP and MJ constructed as described above, the vibration model MP is adjusted so that the vibration model MP corresponds to the vibration input point from the suspension mounting portion.
(Excitation point) The PIP is set at a position that is 12 cm inward in the lengthwise direction from the left end portion of the lower block 41 and becomes the center portion in the widthwise direction.
With the vibration measurement point (response point) POP set at the central part of 2, the vibration input point PIP is set to a frequency of 10
A certain level of vibration from Hz to 1 KHz was applied, and the vibration level transmitted to the vibration measurement point POP at that time was measured. Similarly, for the vibration model MJ, for example, the left and right front suspension mounting portions 22 and 2 are also used.
In order to correspond to the vibration input point from 5, the vibration input point (excitation point) PIJ is set at a position which is 12 cm inward in the length direction from the left end portion of the lower block 45 and becomes the center portion in the width direction. In addition, under the condition that the vibration measurement point (response point) POJ is set at the central portion of the upper block 46, vibration of a constant level with a frequency of 10 Hz to 1 KHz is applied to the vibration input point PII. The vibration level transmitted to the vibration measurement point POJ at was measured.

The measurement result of the vibration level of the vibration model MP and the measurement result of the vibration level of the vibration model MI thus performed are shown in the characteristic diagram of FIG. 5 (horizontal axis:
The vibration vibration frequency FV and the vertical axis: vibration level GV) are represented by the curves CP and CI, respectively. A curve CP representing the measurement result of the vibration level of the vibration model MP and a curve CJ representing the measurement result of the vibration level of the vibration model MJ have the vibration vibration frequency FV of the vibration applied to the vibration input points PIP and PIJ, respectively. When the frequency is approximately 20 Hz or less, approximately 25 to 30 Hz, and approximately 50 to 100, the vibration measuring point POJ is determined from the vibration level GV detected at the vibration measuring point POP.
The vibration level GV detected at is larger,
In other frequency regions, between 30 and 50 Hz, and particularly in the region of approximately 120 Hz or higher, the vibration measuring point PO is compared with the vibration level GV detected at the vibration measuring point POP.
It is shown that the vibration level GV detected at J is significantly reduced.

From this, the vibration frequency is approximately 30 to 50.
With respect to the vibration of Hz or approximately 120 Hz or more, compared with the vibration transmission from the lower block 41 to the central portion of the upper block 42 in the vibration model MP, the lower block 45 to the upper block in the vibration model MJ. 46
It is understood that the vibration transmission to the central portion of the vehicle is significantly suppressed, and such a vibration transmission characteristic of the vibration model MI is the same as that of the vehicle body structure of the frame-equipped vehicle according to the present invention to which the vibration model MJ corresponds. It represents the vibration transmission characteristics that it has. Also, in general, in the body of an automobile,
Vibration from a road surface having a vibration frequency of approximately 120 Hz to 1 KHz is uncomfortable vibration for an occupant in a cabin forming portion provided on the vehicle body. Therefore, according to the vehicle body structure of the vehicle with the frame according to the present invention, the unpleasant vibration transmitted to the occupant in the cabin forming portion 13 of the vehicle body portion 11 is effectively suppressed, and the riding comfort felt by the occupant is improved and The interior of the cabin forming portion 13 can be quieted.

It should be noted that the cabin forming portion of the vehicle body portion is set to have a rigidity or mass larger than those of the vehicle portion portions (front portion and rear portion) before and after the cabin forming portion, but the vibrations performed when the independent type is not used. The experimental results of the model experiment are shown in FIG. Further, FIG. 6 shows an outline of the vibration model MI used in this experiment. The model configuration, main dimensions, weight and the like shown in FIG. 6 are as follows. That is, in the vibration model MI, the lower block 45 ′ corresponding to the frame member supports the upper block 46 ′ corresponding to the vehicle body via the elastic members 47 ′ corresponding to the plurality of mount members. The lower block 45 is made of iron, and both ends 4
5'A and 45'B are made thicker and end 45'A
The central portion 45'C sandwiched between the end portion 45'B and the end portion 45'B is formed as a thin portion. Regarding the size and weight, the length LFI is 81 cm, the width WFI is 5 cm, and both end portions 45A, 4 are formed.
5B each thickness TFEI is 1.25 cm, central part 4
The thickness TFCI of 5C is 0.35cm and
Each of the both end portions 45A and 45B has a rigidity or weight greater than that of the central portion 45C. The upper block 46 'is made of iron, and both end portions 46'A, 46' are
B is a thin-walled portion, and the end portion 46'A and the end portion 46 '
A central portion 46'C sandwiched by B and B is formed as a thick portion, and its size and weight are such that the length LBI is 8
1 cm, width WBI is 5 cm, thickness TBEI of both end portions 46'A, 46'B is 1.25 cm, thickness TBCI of central portion 46'C is 2.15 cm, and mass of central portion 46'C is Is greater than the mass of each of the ends 46'A and 46'B, so that the central portion 46C has greater rigidity or weight than the ends 46'A and 46'B, respectively. Was taken. Further, the elastic member 4
Seven 7's were arranged between the lower block 45 'and the upper block 46, and the total spring constant was set to 830 N / mm.

This vibration model experiment has already been disclosed in Japanese Patent Application No. 4-179557 filed by the applicant of the present application, in which both the vehicle body and the frame member are evenly distributed over the entire body. As the vibration model MP corresponding to the conventional vehicle body structure having rigidity and mass, the same one as in the present application was used, and the measuring method was also similar to that in the present application. By comparing the graph of FIG. 5 with the graph of FIG.
It is understood that the vibration model according to the present invention, which is an independent cabin type that is separated and independent from the (front portion and rear portion), has a greater vibration reduction effect (particularly in the range of approximately 250 Hz to approximately 500 Hz).

As described above, according to the vehicle body structure according to the present embodiment, the cabin forming portion 13 of the vehicle body portion 11 is formed.
Is formed separately from the front portion 11F and the rear portion 11R, the front portion 11 of the vehicle body portion 11 is
The F and the rear portion 11R can be effectively utilized as members for increasing at least one of rigidity and mass of the frame member 12 with respect to the front portion 12F and the rear portion 12R, respectively. That is, the front portion 12F and the rear portion 12R of the frame member 12 are set to have a larger rigidity and / or mass than the intermediate portion 12M located between the front portion 12F and the rear portion 12R. The frame structure and the cabin forming portion 13 are set to have a rigidity and / or a mass larger than those of the vehicle body main body portion before and after the frame forming portion 13.
The vehicle body structure in which the frame is arranged at a position corresponding to the intermediate portion 12M of the frame member 12 can be made to be an extremely limited structure, and vibration and noise input to the cabin forming portion 13 can be further reduced. Can be done.

By the way, when the cabin forming portion 13 of the vehicle body portion 11 is an independent cabin portion separated from the front and rear portions thereof (the front portion 11F and the rear portion 11R), the vibration input from the frame member 12 side is considered. Can have an extremely advantageous structure, but the front and rear support of the cabin forming part 13 becomes insufficient, and the cabin forming part 13 itself is easily affected by pitching, rolling, bouncing, etc. Rigid body vibration is likely to occur as a whole. Therefore, in the present embodiment, the rigid structure vibration of the independent cabin portion 13 as a whole is modified by variously devising the supporting structure of the cabin forming portion 13 (independent cabin portion), particularly the mounting position of the mount member or the spring constant. Is trying to suppress.

Next, the support structure of the independent cabin portion 13 will be described. As shown in FIG. 1, the independent cabin portion 13 includes mount members 50C, 50D, 50.
The intermediate portion 1 of the frame member 12 is on the lower side through E.
The rear side (mounting portion B) is supported by the vehicle body rear portion 11R via the mounting member 50B while being supported by 2M. Further, the mount member 50A provided on the mount portion A on the front side of the independent cabin portion 13 includes the left and right side members 14L,
Mount attachment portions 51, 51 extending upward from 14R
It is attached between the mount mounting part 5
The front side portion 12F of the frame member 12 is integrally fixed to the vehicle body front portion 11F, so that the components 1, 51 are integrated with the vehicle body front portion 11F. Incidentally, as the front shape of the mount mounting portion, for example, those shown in FIGS. 11 and 12 can be considered. The mount mounting portion 52 shown in FIG. 11 is reinforced by making it a gate type, and the mount mounting portion 53 shown in FIG. 12 is crossed in an X shape.

In this embodiment, the mount members 50A and 50B for supporting the front side and the rear side of the independent cabin portion 13 are, for example, the front mount member 50A, as shown in FIG. It is arranged above the center of gravity position G of 13. in this way,
By disposing the mount members 50A and 50B that respectively support the front side and the rear side of the independent cabin portion 13 above the center of gravity position G of the independent cabin portion 13, when the pitching or rolling acts on the independent cabin portion 13, It is possible to restrain the portion where the movement locus becomes large and to effectively suppress the rigid body vibration of the cabin forming portion.

Further, in this embodiment, the mount members 50A and 50B respectively disposed on the front side and the rear side of the independent cabin portion 13 have spring constants in the vertical direction and the horizontal direction, respectively. The spring constant of 50B in the front-rear direction and the mount members 50C, 5 arranged between the independent cabin portion 13 and the frame member 12
It is set higher than the 0D and 50E spring constants in all directions. That is, it is usually desirable to increase the spring constant in order to enhance the restraint property, and particularly to decrease the spring constant in order to enhance the high frequency vibration absorption property. However, the spring constant of the mount members 50A and 50B is By setting as described above, the restraint property when the pitching, rolling or bouncing acts on the independent cabin part 13 is suppressed and the rigid body vibration is suppressed, and the high frequency vibration input from the frame member 12 side is effective. Therefore, the comfort inside the independent cabin portion 13 can be further improved.

The specific structure of the front and rear mount members 50A and 50B of the independent cabin portion 13 will be described by taking the front mount member 50A as an example. FIG.
As shown in FIG. 5, the mount member 50A includes an outer cylinder 57 fixed to a panel member 54 (hereinafter, referred to as a frame side panel) integrally provided with the mount attachment portion 51 provided on the vehicle body front side, An elastic body 58 made of, for example, rubber is provided between the outer cylinder 57 and the inner cylinder 56 provided coaxially.
The panel member 55 (which is integrally provided on the front side portion of the independent cabin portion 13 by using the bolt member 59b and the nut 59n which are inserted through the inner peripheral portion of the inner cylinder 56). Hereinafter, the inner cylinder 56 is integrally fastened and fixed to a cabin side panel). With this configuration, the spring constants of the mount member 50A in the up-down direction and the left-right direction can be reliably made higher than the spring constants of the mount member 50A in the front-rear direction.

When an elastic body such as rubber is used, for example, as shown in FIG. 14, the elastic body 62 is loaded in a cylindrical case 61 with a bottom fixed to the frame side panel 54, and the cabin side panel is mounted. Rod member 63 fixed to 55
May be inserted into the elastic body 62. Also in this case, the spring constants of the mount member 60A in the up-down direction and the left-right direction can be reliably made higher than the spring constants of the mount member 60A in the front-rear direction.

Various specific configurations are conceivable as the mount member for supporting the front side and the rear side of the independent cabin portion 13. Another embodiment in which the structure of the mount member is different will be described below. In the following description, the same components as those in the first embodiment are designated by the same reference numerals, and further description will be omitted. FIG. 15 shows a mount member 70A according to the second embodiment. The mount member 70A includes a steel member 72 integrally fixed to the frame side panel 54 and an electromagnetic device 71 integrally fixed to the cabin side panel 55. The electromagnetic device 71 is, for example, It is designed to be energized when a vibration with a large amplitude is input, such as when traveling on a rough road or when turning a vehicle. Then, when energized, the cylindrical movable portion 73 is projected from the electromagnetic device 71 side, and the steel member 7
2 is inserted into the receiving portion 74 provided in the second. As a result, the mount member 7 is vertically and horizontally oriented.
The restraint property as 0A (hence the spring constant) is enhanced.
On the other hand, when there is no large-amplitude vibration input, the electromagnetic device 7
1 is maintained in the non-energized state, and the movable portion 73 is the electromagnetic device 71.
The electromagnetic device 71 and the steel member 7 as they are housed inside
No restraint force acts between the two and it is kept free. That is, for pitching, rolling, or bouncing that is normally input when traveling on a rough road or turning the vehicle, the electromagnetic force of the electromagnetic device 71 is energized to increase the restraint by the mount member 70A. In this case, the restraint by the mount member 70A can be made free and the high frequency vibration can be effectively absorbed.

16 and 17 show a mount member 80A according to the third embodiment and a bar-shaped electromagnet 8 as its component.
1 is shown. The mount member 80A is a ring-shaped electromagnet 8 integrally fixed to the frame side panel 54.
2 and a rod-shaped electromagnet 81 (see FIG. 17) integrally fixed to the cabin side panel 55. Both electromagnets 81 and 82 have the same polarity, and by controlling the energization state of the bar-shaped electromagnet 81 in the same manner as in the second embodiment, the restraint by the mount member 80A is performed only when a large amplitude vibration is input. You can improve your sex. In this case, both electromagnets may be made of permanent magnets. That is, as the amplitude becomes larger and the distance between the facing portions of both electromagnets becomes shorter, a larger electromagnetic force acts, so that the restraint property can be enhanced according to the amplitude.

FIG. 18 shows a mount member 90A according to the fourth embodiment. This mount member 90A is an electromagnet 9 attached to the flange portion of the independent cabin portion 93.
5 and the electromagnet 9 attached to the vehicle body front portion 91F
6 and 6. The polarities of both electromagnets 95 and 96 are set to be the same as each other, and similarly to the second and third embodiments, current is energized only when a large amplitude vibration is input, and the mount for vertical vibration is mounted. The spring constant (and therefore the restraint) of the member 90A can be increased.
The electromagnets 95 and 96 may be permanent magnets. Further, in FIG. 18, the electromagnets 95, 96 are arranged only in the vertical direction.
However, a mounting member having a similar structure is provided in the left-right direction.

FIG. 19 shows a mount member 100A according to the fifth embodiment. This mount member 100A is
Between the support plate 101 fixed to the frame side panel 54 and the support plate 102 fixed to the cabin side panel 55,
For example, an elastic body 107 made of rubber is fixed, and the elastic body 10 is fixed.
7, two liquid chambers 104 communicating with each other through an orifice 105 are formed, the magnetic fluid is filled in the liquid chambers 104, 104, and a coil 106 is arranged around the orifice 105. Is. In the mount member 100A, normally, the magnetic fluid moves relatively freely between the liquid chambers 104 via the orifices 105, so that the spring constant is not only in the front-rear direction but also in the up-down or left-right direction. It is relatively low.
When a large amplitude vibration is input, the coil 10
6 is energized, so that the orifice 105 is mainly used.
The magnetic fluid passing through is magnetically restrained and becomes difficult to move. As a result, the spring constant in the up-down direction or the left-right direction is higher than in the front-rear direction, and the restraining force is increased.

20 and 21 show mount members 110A and 110B according to the sixth embodiment and their mounting states. In this embodiment, the mount members 110A, 1
As the 10B, a so-called shock absorber is used, and the shock absorber 110A attached to the front mount portion A of the independent cabin portion 13 is mounted on the mount attachment portion 51 by inclining 45 degrees in the vertical direction and 45 degrees inward in the horizontal direction. It is installed. On the other hand, the shock absorber 110B attached to the rear mount portion B is also attached to the vehicle body rear portion 11R in a similarly tilted state. On the other hand, mount members 50C, 50D, which are arranged between the independent cabin portion 13 and the intermediate portion 12M of the frame member 12,
Each of 50E is composed of a normal rubber mount member.

As described above, since the shock absorbers 110A and 110B are used as the mount members provided on the front mount portion A and the rear mount portion B of the independent cabin portion 13, the mount members of the mount portions A and B are , The damping characteristic is that of the independent cabin part 1
3 is higher than the damping characteristics of the mount members 50C, 50D, 50E arranged between the frame member 12 and the frame member 12. In addition, each of the shock absorbers 110 described above
By mounting the A and 110B in a state in which they are inclined in the vertical direction and the horizontal direction as described above, it becomes possible to perform the adjustment according to the direction of the damping characteristic, which is difficult with a normal rubber mount member. As described above, according to this embodiment, the damping characteristics of the mount members (shock absorbers 110A and 110B) attached to the front and rear mount portions A and B of the independent cabin portion 13 are set to the independent Mount members 50C, 50 arranged between the cabin portion 13 and the frame member 12
By setting it higher than the damping characteristics of D and 50E, the vibration peak at the resonance point can be lowered gently, and at the same time, the cutoff property against the vibration of the frequency above the resonance point input from the frame member 12 side is effective. Therefore, the comfort inside the independent cabin portion 13 can be further improved.

[Brief description of drawings]

FIG. 1 is a side view showing a vehicle body structure of an automobile with a frame according to a first embodiment of the present invention.

FIG. 2 is an explanatory plan view showing a vehicle body structure of the automobile.

FIG. 3 is a perspective view schematically showing a vibration model used in a vibration model experiment related to the vehicle body structure of the automobile.

FIG. 4 is a perspective view schematically showing a vibration model used in a vibration model experiment related to the vehicle body structure of the automobile.

FIG. 5 is a characteristic diagram showing a result of a vibration model experiment related to the vehicle body structure of the automobile.

FIG. 6 is a perspective view schematically showing a vibration model used in a vibration model experiment related to a conventional vehicle body structure.

FIG. 7 is a characteristic diagram showing a result of a vibration model experiment related to a conventional vehicle body structure.

FIG. 8 is a perspective view showing a mount structure of a cabin forming portion of the automobile according to the first embodiment.

FIG. 9 is a side view showing the mount structure of the cabin forming portion of the automobile according to the first embodiment.

FIG. 10 is an explanatory diagram schematically showing the relationship between the mount position and the center of gravity of the cabin forming portion.

FIG. 11 is a front explanatory view showing an example of a mount attaching portion on the frame side.

FIG. 12 is a front view showing another example of the mount attaching portion on the frame side.

FIG. 13 is a cross-sectional explanatory view showing a specific structure of the mount member according to the first embodiment.

FIG. 14 is an explanatory sectional view showing a modification of the mount member according to the first embodiment.

FIG. 15 is a sectional explanatory view showing a specific structure of a mount member according to a second embodiment of the present invention.

FIG. 16 is an explanatory sectional view showing the specific structure of the mount member according to the third embodiment of the present invention.

FIG. 17 is an explanatory diagram showing a rod-shaped electromagnet of the mount member according to the third embodiment.

FIG. 18 is a side view showing the mount structure according to the fourth embodiment of the present invention.

FIG. 19 is a sectional explanatory view showing a specific structure of the mount member according to the fifth embodiment of the present invention.

FIG. 20 is a perspective view showing a mount structure of a cabin forming portion of an automobile according to a sixth embodiment of the present invention.

FIG. 21 is a side view showing the mount structure of the cabin forming portion of the automobile according to the sixth embodiment.

[Explanation of symbols]

11 ... Body part 11F ... Body front part 11R ... Car body rear part 12 ... Frame member 12F ... Frame member front part 12R ... Frame member rear part 13 ... Cabin formation part (independent cabin part) 50A, 50B, 60A, 70A, 80A, 90A, 100A, 1
10A, 110B ... mounting member 50C, 50D, 50E ... mounting member

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takanobu Kamura, No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Seiichi Nakabayashi, No. 3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Masato Hirokawa, 3-1, Shinchi Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) Inventor, Katsuhiro Nakamura 3-1-1 Shinchu, Fuchu-cho, Hiroshima Prefecture Mazda Co., Ltd.

Claims (4)

[Claims] 1. A vehicle body structure for an automobile with a frame, comprising a vehicle body main body portion including a cabin forming portion, and a frame member supporting the vehicle body main body portion from below, wherein a front side portion and a rear side portion of the frame member are provided. A suspension mounting portion is provided on each of the portions, and the front side portion and the rear side portion are set to have a larger rigidity and / or mass than an intermediate portion located between the front side portion and the rear side portion. On the other hand, the vehicle body part is composed of a front part, a rear part, and a cabin forming part located between these parts, and the cabin forming part is separated from the front part and the rear part. And the lower side thereof is supported only by the intermediate portion of the frame member. Body structure. 2. The vehicle body structure for a vehicle with a frame according to claim 1, wherein mount members are respectively disposed between the cabin forming portion and the front portion and the rear portion, and these mount members are the above-mentioned members. A vehicle body structure for an automobile with a frame, which is arranged above a center of gravity of a cabin forming portion. 3. The vehicle body structure for an automobile with a frame according to claim 1 or 2, wherein each mount member disposed between the cabin forming portion and the front portion and the rear portion is a damping member thereof. A vehicle body structure for an automobile with a frame, wherein a characteristic is set to be higher than a damping characteristic of a mount member arranged between the cabin forming portion and the frame member. 4. The vehicle body structure for a vehicle with a frame according to claim 1 or 2, wherein each mount member disposed between the cabin forming portion and the front portion and the rear portion has its upper and lower portions. The spring constants in the horizontal and horizontal directions are set to be higher than the spring constants in the front-rear direction of the mount member and the spring constants in all directions of the mount member arranged between the cabin forming portion and the frame member. The body structure of an automobile with a frame characterized by being