JP4212756B2 - A coconut frame structure for a cab-over type freight vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical frame structure of a cab over type freight vehicle that secures a passenger's living space by suppressing deformation of the cab against frontal collision and rear-end collision of the vehicle.
[0002]
[Prior art]
In a cab-over type freight vehicle with a cab (cab) mounted on the front of the palm frame and the driver's seat positioned in front of the internal combustion engine, the front end of the palm frame during a frontal collision with the barrier By effectively striking against the barrier and deforming it, the collision energy is absorbed, the living space of the cab is secured, and the safety of the occupant is maintained.
[0003]
In a small cab-over type freight vehicle, various accessories are installed in the narrow space of the palm frame, so the width of the palm frame is curved so that the width of the palm frame widens from the front to the rear. The internal combustion engine is supported by the motor. In the above-described small cap-over type freight vehicle, in order to secure the living space of the cap at the time of a frontal collision with the barrier, the front half of the side frame of the palm frame has a closed cross-sectional structure. Deformation is suppressed and safety is ensured. However, if the front half of the side frame of the palm frame has a closed cross-sectional structure, there is a high risk that the driver of the rear-end collision vehicle will be injured when the carry-over type freight vehicle collides with the front freight vehicle.
[0004]
As shown in FIGS. 6 to 8, the carry-over type freight vehicle has a pair of lateral members coupled to a pair of left and right side frames 7 to form a palm frame 20, and slightly rearward from the front ends of the pair of left and right side frames 7. The internal combustion engine 10 is supported by the portion, and the front, rear, left and right corners of the cap 31 are supported on the side frame 7 so that the driver's seating position is on the upper side of the internal combustion engine 10. The front wheel 26 is supported by the palm frame 20 so as to be positioned approximately at the center of the cap 31 in the front-rear direction.
[0005]
As shown in FIG. 8, in the conventional coconut frame 20, a reinforcing member 29 having a closed cross section is coupled to the front end of the side frame 7 having a U-shaped cross section. The transverse members are joined. The front end floor portion of the cap 31 is supported by the tilt shaft on the cap mount 22 of the support plate 21 extending upward from the front end portion of the side frame 7.
[0006]
When the vehicle collides front with a flat barrier 30 as shown in FIG. 6, the front bumper hits the barrier 30, the collision energy is supported by the pair of left and right side frames 7, and deformation of the cap 31 is minimized. However, as shown in FIG. 7, when the vehicle collides with the preceding vehicle, if there is a difference in height between the coconut frame 20 of the preceding vehicle and the coconut frame 20 of the trailing vehicle, the cap 31 moves to the loading platform 32 of the preceding vehicle. There is a risk of crashing directly and crashing the car, causing danger to the driver's life. That is, as shown in FIG. 9, the load applied to the rear-end collision vehicle acts on the cap 31 and the cap mount 22 that supports the front end of the cap 31, and the cap mount 22 separates from the front end of the side frame 7 and moves rearward. The front wall of 31 is greatly retracted.
[0007]
Therefore, if the side frame 7 is reinforced as a closed cross-section structure considering only the frontal collision, the side of the collision load acting on the cap 31 at the time of rear-end collision and the cap mount 22 supporting the cap 31 on the side frame 7 can be reduced. In order for the strength of the frame 7 to be too strong and the side frame 7 to bend up and down effectively, the coupling strength between the cab mount 22 and the side frame 7 must be made quite strong, and an actual structure should be established. Is quite difficult.
[0008]
When the side frame 7 has an open cross-sectional structure and the coupling strength between the cab mount 22 and the side frame 7 is strengthened, the side frame 7 can be bent in the vertical direction during the rear-end collision of the vehicle. If the side frame 7 is curved so that the width of the rear portion (internal combustion engine mounting portion) of the palm frame 20 becomes wide at the time of a collision, the bending portion tends to bend in the left-right direction. It becomes difficult to secure a living space. Therefore, it is conceivable to straighten the side frame 7 in the front-rear direction in order to eliminate the lateral curvature of the side frame 7, but the degree of freedom in the layout of the vehicle is reduced, and the advantages of the small-sized carry-over type freight vehicle are impaired.
[0009]
In the palm frame structure of a carryover type freight vehicle disclosed in Japanese Patent Application Laid- Open No. 8-188174, a plurality of holes and leads are formed on a pair of left and right side frames, with a closed cross section and on both side walls with a space in the front-rear direction. The shock absorbing member provided with a notch is supported, the front bumper is supported at the front end of the shock absorbing member, and the impact received from the front bumper at the time of frontal collision of the vehicle is received from the hole, lead, notch, etc. of the shock absorbing member. Absorbed by crushing, it suppresses deformation of the coconut frame and cap and secures the occupant's living space. However, the above-described structure of the cylindrical frame of the carry-over type freight vehicle increases the cost in that an impact absorbing member is provided in addition to the coconut frame, and the relationship with the front-wheel suspension mechanism particularly in the case of a small cab-over type freight vehicle. Therefore, it is difficult to secure a space for arranging the shock absorbing member.
[0010]
[Problems to be solved by the invention]
In view of the above-mentioned problems, the object of the present invention is to effectively transmit an input to the front end of the palm frame or the front of the cap to the palm frame in both cases of a frontal collision and a rear-end collision of the vehicle. It is an object of the present invention to provide a coconut frame structure for a cap-over type freight vehicle that absorbs collision energy and secures a living space for the cab.
[0011]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the structure of the present invention is such that a first horizontal member is coupled to the front end portions of a pair of left and right side frames having a U-shaped cross section, and the cap mount is disposed on the upper surface of the front end portion of the side frame. A front end floor portion of the cap is supported by a tilt shaft, and a second lateral member is coupled to a front portion of the internal combustion engine supported between a pair of left and right side frames. The first lateral member and the second lateral member A closing plate having the side frame as a closed cross section is coupled to the upper and lower edges of each side frame in a portion between the first and second transverse members against the collision load. An opening that allows deformation of the side frame and the closing plate is provided in the portion .
[0012]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, in the event of a rear-end collision of a vehicle, by providing a portion weaker than the support portion of the front end floor portion of the cap with respect to the side frame near the front end of the side frame, the side frame is deformed integrally with the cap, Reduce the amount of retreat and secure a living space. For this reason, the upper and lower edges of the side frame that forms a pair of left and right cross-sections that constitute the palm frame are combined with a closing plate that makes the side frame a closed sectional structure, and an opening is provided near the front end of the closing plate, At the time of frontal collision of the vehicle, the left and right side frames are bent at the opening to absorb the collision energy. The internal combustion engine is supported in a part slightly rearward from the front ends of the pair of left and right side frames, the front part is narrower than the internal combustion engine of the pair of left and right side frames, and a front wheel suspension mechanism is disposed in this part. To do.
[0013]
In other words, the second lateral member is disposed in front of the radiator of the internal combustion engine of the pair of left and right side frames, and a portion between the first lateral member and the second lateral member at the front end of the side frame. A closing plate having a side frame with a closed cross-sectional structure is coupled, and an opening is provided in the closing plate. The cab supports the front end floor portion with a tilt mount on a cab mount disposed on the front end of the side frame, that is, the upper surface of the connecting portion with the first lateral member, and the rear end floor portion of the cab spans the left and right side frames. On the inverted U-shaped ridge, it is locked so as not to be displaced from front to back and from side to side. Therefore, at the time of frontal collision of the vehicle or rear-end collision with the preceding vehicle, the side frame bends in the vertical direction from the opening portion of the closing plate to absorb the collision energy. At this time, the front wall of the cap is also deformed and retracted, but the strength of the opening of the closing plate is weaker than the cap mount that supports the front end floor of the cap, so that only the cap is deformed and retracted. No, the space for the cab is secured.
[0014]
【Example】
FIG. 1 is a plan view showing a front half portion of a palm frame of a carryover type freight vehicle according to the present invention. The palm frame 20 is configured by connecting a pair of left and right side frames 7 having a U-shaped cross section by a plurality of horizontal members. In the illustrated embodiment, the first transverse member 2 is firmly coupled to the front end of the side frame 7. The second lateral member 5 is coupled to a portion separated from the lateral member 2 rearward by a predetermined distance, and the front end of the leaf spring 25 that suspends the front wheel 26 (FIG. 4) near both ends of the lateral member 5 is spring-supported. The member 4 is supported on the side frame 7, and the rear end of the leaf spring 25 is supported on the side frame 7 by the spring support member 8. The distance between the pair of left and right side frames 7 is widened behind the horizontal member 5, and the radiator 6 is supported by the support member 6 a and the internal combustion engine 10 is supported by the engine mount 9 at the widened portion of the side frame 7. A clutch 12 and a transmission 13 are integrally coupled to the rear portion of the internal combustion engine 10, and the rotation of the output shaft of the transmission 13 is transmitted to a final reduction gear of the rear wheel 27 (see FIG. 7) via a known propulsion shaft. It is done.
[0015]
As shown in FIG. 2, according to the present invention, a closing plate 17 is coupled to the upper and lower edges 7 a of the side frame 7 on the front side of the engine mount 9 that supports the internal combustion engine 10 of the side frame 7. The frame 7 has a closed cross-sectional structure. A reinforcing member 29 having a square cross section is coupled to the front end of each side frame 7, and the end of the lateral member 2 is abutted between the reinforcing members 29. A cab mount 22 having a lateral shaft hole is supported by a support plate 21 protruding upward at the front end portion of the side frame 7, and the front end floor portion of the cab 31 is supported by the tilt mount on the cab mount 22. The rear end floor portion of the cap 31 is locked on an inverted U-shaped ridge spanned over the left and right side frames 7 so as not to be displaced from front to back and from side to side. An opening 23 is provided in the closing plate 17 so that the side frame 7 is crushed between the lateral member 5 and the lateral member 2 at the time of a frontal collision. The vertical dimension of the opening 23 is substantially equal to the interval between the upper and lower edge portions 7a of the side frame 7, and the longitudinal dimension of the opening 23 is longer than the vertical dimension. The opening 23 also serves as a work hole for mounting the steering mechanism unit.
[0016]
As described above, the closing plate 17 is joined to the edge portion 7a of the side frame 7 from the internal combustion engine mounting portion to the front end of the side frame 7 to form a closed cross section, and the portion between the horizontal member 2 and the horizontal member 5 is closed. By providing the opening 23 in the plate 17, when the frontal collision of the vehicle occurs, particularly when the vehicle collides with the loading platform 32 and the palm frame 20 of the front vehicle, the front wall of the cap 31 is formed as shown in FIGS. In addition to being crushed, the left and right side frames 7 are crushed at the opening 23 and curved upward or downward to absorb the collision load. Since the collision load is absorbed not only by the front wall of the cap 31 but also by deformation of the side frame 7, the amount of deformation of the cap 31 is suppressed and a living space is secured.
[0017]
At the time of the rear-end collision of the vehicle, not only the front surface of the cap 31 is deformed, but also the portion of the opening 23 of the closing plate 17 of the side frame 7 is bent upward or downward. At this time, the collision load crushes the opening 23 of the closing plate 17, and as a result, the collision load concentrates on the side frame 7 having a locally reduced section modulus. It can be bent up and down. As shown in FIG. 5, the initial drag when the opening 23 of the closing plate 17 of the side frame 7 is crushed is not excessive and the deceleration is relatively small. When the opening 23 of the closing plate 17 is crushed, the front and rear portions of the opening 23 of the closing plate 17 are adhered to each other and become strong against a load in the front and rear direction. As indicated at 42, a moderate drag is sustained over a longer deformation stroke than in the case of the conventional vehicle indicated by line 41. That is, the collision energy is efficiently absorbed and the living space of the cap 31 is secured.
[0018]
【The invention's effect】
As described above, according to the present invention , the first horizontal member is coupled to the front end portions of the pair of left and right side frames having a U-shaped cross section, and the front end floor portion of the cap is mounted on the cap mount disposed on the upper surface of the front end portion of the side frame. Is supported by a tilt shaft, and a second lateral member is coupled to a front portion of the internal combustion engine supported between the pair of left and right side frames, and a portion between the first lateral member and the second lateral member is coupled. The upper and lower edges of each side frame are connected with a closing plate having a closed cross section as the side frame, and the side plate is connected to the closing plate at a portion between the first lateral member and the second lateral member with respect to a collision load. Since the frame and the opening that allows deformation of the closing plate are provided, the side frame deformation characteristics equivalent to axial collapse are shown while preventing the deformation of the curved part (widened part) of the side frame at the time of frontal collision of the vehicle. Prevents bending of the support part of the cap while causing the side frame to bend in the vertical direction, and the impact energy is efficiently absorbed by the deformation of the palm frame. Is, survival space cab is ensured.
[Brief description of the drawings]
FIG. 1 is a plan view of a palm frame of a carryover type freight vehicle according to the present invention.
FIG. 2 is a perspective view showing a main part of the same palm frame structure.
FIG. 3 is a side view showing a deformed state of a palm frame structure at the time of a vehicle collision.
FIG. 4 is a side view showing a deformed state of the cap at the time of rear-end collision of the vehicle.
FIG. 5 is a diagram showing a relationship between displacement and load of each palm frame between a vehicle according to the present invention and a conventional vehicle.
FIG. 6 is a side view showing a state immediately before a frontal collision of the vehicle.
FIG. 7 is a side view showing a state immediately before the rear-end collision of the vehicle.
FIG. 8 is a perspective view showing a cap support portion of a side frame of a conventional vehicle.
FIG. 9 is a side view showing a deformed state of a cap at the time of rear-end collision of a conventional vehicle.
[Explanation of symbols]
2: First transverse member 5: Second transverse member 7: Side frame 7a: Edge 10: Internal combustion engine 17: Closing plate 20: Palm frame 22: Cap mount 23: Opening 25: Leaf spring 26: Front wheel 27: Rear wheel 30: Barrier 31: Cab

Claims (1)

A first horizontal member is coupled to the front end portions of a pair of left and right side frames having a U-shaped cross section, and the front end floor portion of the cap is supported by a tilt shaft on a cap mount disposed on the upper surface of the front end portion of the side frame. A second transverse member is coupled to the front portion of the internal combustion engine supported between the pair of side frames, and the upper and lower edges of each side frame at the portion between the first transverse member and the second transverse member. A closing plate having the side frame as a closed cross section is coupled, and the side frame and the closing plate are deformed at a portion between the first transverse member and the second transverse member against a collision load on the closing plate. A cylindrical frame structure of a cab-over type freight vehicle characterized by providing an opening to allow.

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