JP3797520B2 - Ladder fire truck - Google Patents

Description

[0001]
The present invention comprises a ladder-type frame supported above a front axle and a rear axle via a suspension, and a cab mounted on the frame . It relates to the ladder fire engine which aimed at improvement .
[0002]
[Prior art]
In a conventional low-floor type double cab vehicle used for a fire engine such as a ladder car, a water pump car, a rescue work vehicle, etc., as shown in FIG. 15, the cab 21 has an integrally formed substantially horizontal straight frame 32. It was mounted on the front end. Therefore, the height of the floor surface of the cab 21 is determined by the ground height up to the upper surface of the frame 32, and the height above the floor surface of the cab 21 almost determines the lift.
[0003]
The ground clearance up to the upper surface of the frame 32 is determined by the vertical action dimensions of the overlap leaf spring FS used for the front axle suspension shown in FIGS. 16 and 17, the parent-child spring RS used for the rear axle suspension, and the front and rear tires WF. , WR is determined by the ground clearance of the front and rear axles FA and RA.
[0004]
Although such a great restriction by the suspension has been devised to reduce the floor height of the cab 21 as much as possible, as a result, even if the floor surface related to lifting and lowering is lowered, various floor surface protrusions are generated. Therefore, the entire floor surface is not flat, and the mobility and comfort in the room are impaired.
[0005]
The above-described ground clearance and flatness have been particularly problematic for fire trucks that require agile indoor operation and agile lifting during a fire emergency.
[0006]
Therefore, there is a method of lowering the height position of the engine in order to lower the ground height of the cab 21, but a great effect cannot be obtained due to the restriction due to the suspension configuration described above.
[0007]
Further, as shown in FIG. 15, the proximity of the vehicle to the object is determined by the front overhang FOH, which is the horizontal distance between the ground point of the front wheel WF and the lower surface of the front end of the vehicle, and the ground height h at the front overhang FOH. , Determined by. That is, the obstacle S can be climbed up to h, and the approach to the slope is determined by the height h and the approach angle α formed by the front overhang FOH. In FIG. 15, in the case of the long cab 21D, the front overhang FOH becomes large, the approach angle becomes β, and the approachability to the slope becomes unclear.
[0008]
As described above, on the one hand, lowering the ground clearance of the cab to improve the liftability has a difficult relationship of compromising the approachability of the vehicle on the other hand.
[0009]
Japanese Utility Model Laid-Open No. 5-62272 discloses a technique for arranging the engine position behind the front axle, but this method alone is less effective due to the restriction of the minimum ground clearance due to the suspension described above. There is no direct effect on improving the corners.
[0010]
[Problems to be solved by the invention]
The present invention has been proposed in view of the above-mentioned drawbacks of the prior art, and an object of the present invention is to provide a low-floor double cab ladder fire truck having good liftability, good habitability, and good approachability.
[0011]
[Means for Solving the Problems]
According to the present invention, in the ladder fire engine equipped with the double cab (1) using the ladder frame (2), the ladder frame (2) extends from the front axle (11) slightly to the rear end. The hollow rectangular material (15Ba) is joined to the tip of the ladder frame (2), and the front frame (2B) is attached to the front portion of the hollow rectangular material (15Ba) with a support plate (15Bb). Combined, lower the upper surface of the front frame (2B) from the lower surface of the ladder frame (2) so that both have a vertical difference, the double cab (1) is mounted on the front frame (2B), and the front axle (11) is the front hydraulic suspension (FS), the rear axle (12) is suspended by the rear hydraulic suspension (RS), and the front and rear hydraulic suspensions (FS and RS) are (G) is connected to front and rear hydraulic cylinders (FSh, FSr; RSh, RSr) via front axle control valve (Vf) and rear axle control valve (Vr), respectively. A front axle vehicle height adjustment switch (SWf) is connected to the control valve (Vf), a rear axle vehicle height adjustment switch (SWr) is connected to the rear axle control valve (Vr), and the front axle vehicle height adjustment switch (SWf) and By operating the rear axle height adjustment switch (SWr) and simultaneously operating the front and rear hydraulic cylinders (FSh, FSr; RSh, RSr), either one of the front and rear hydraulic cylinders It has a function of selectively operating the approach angle / departure angle adjustment by the operation of.
[0012]
According to the ladder fire engine of the present invention configured as described above, a front frame having a low ground clearance is coupled to the front end portion of the frame by a coupling member, and the cab is mounted on the front frame. It can be lowered to improve the liftability, and the floor surface can be flattened with an allowance for the floor surface height to improve indoor comfort and operability. If the cab is a double cab, the floor height of the front and rear seats can be made the same, and the front and rear seats can be easily moved.
[0013]
In addition, since the suspension is a fluid suspension, the vehicle height can be freely changed. For example, the vehicle height can be lowered during raising and lowering to improve the raising and lowering performance, and the vehicle height can be raised and the running performance can be improved at irregular sites.
As described above, it is possible to improve the elevating performance and the traveling performance at the irregular site at the same time.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
1 to 4, a low-floor type double cab vehicle T includes a ladder frame supported by front and rear axles 11, 12 and a front fluid suspension FS and a rear fluid suspension RS mounted above the front and rear axles 11, 12. 2 and a cab 1 mounted on the front portion of the ladder-type frame 2 are schematically configured. Here, FIG. 2 shows a ladder fire engine in which a ladder is mounted on the low floor type double vehicle T of FIG.
[0016]
The front axle 11 is a driven shaft in this case, and supports the front and rear portions of the frame 2 from below by the fluid suspension FS and the rear axle 12 by the fluid suspension RS on the driving shaft.
[0017]
The ladder-type frame 2 is formed substantially flat from the rear end portion to the front portion slightly from the front axle 11. Then, referring also to the side view of FIG. 3 and the top view of FIG. 4, the front frame 2 a is coupled by the coupling member 15 slightly in front of the front axle 11.
[0018]
The front frame 2 a is formed so that the cab 1 is mounted at a ground height Hf lower than the ground height Hm of the frame 2. The coupling member 15 includes a terminal plate 15a and a support plate 15b. The front plate 2a of the frame 2 is welded and joined, for example, with the terminal plate 15a, and the front frame 2a is welded and joined to the terminal plate 15a via the support plate 15b. ing. Thus, the front frame 2a offset in the ground height direction by the coupling member 15 with respect to the frame 2 is formed flat to the front end of the vehicle. Note that the method of connecting the frame 2 and the front frame 2a by the connecting member 15a is not based on welding, and may be, for example, bolt connection or fitting connection.
[0019]
As described above, by connecting the separate front frame 2a to the frame 2, it is possible to solve the difficulty of significantly reducing the ground height of the front end portion only by press molding the frame 2.
[0020]
1 and 2 show an example of a double cab, the cab 1 is mounted on a front frame 2a having a low ground height with a flat floor surface (8). In the fluid suspension shown in FIG. 7 showing a hydraulic circuit, hydraulic cylinders FSh, FSr, RSh, and RSr are attached to the left and right of the front and rear axes, and pipes are connected.
In the description of the hydraulic circuit, the reference numerals of the hydraulic cylinder details are limited to the front right hydraulic cylinder FSr and the others are omitted. Further, in the subscripts of each device, r indicates right and h indicates left.
[0021]
In the piping, a high-pressure pipe p0 is connected to a hydraulic pump G that is driven by a power source (not shown). The high-pressure pipe p0 is branched into two at the first branch C1, and one becomes a front pipe p1 for the front axle and goes to the second branch C2 near the front axle via the front axle control valve Vf. The front pipe p1 is branched at the second branch C2, and one is a first high-pressure pipe p1r connected to the high-pressure chamber Cu of the front right hydraulic cylinder FSr, and the other is a second high-pressure pipe p2h. Connected to the high pressure chamber of the hydraulic cylinder FSh.
[0022]
The other of the high-pressure pipe p0 branched at the first branch C1 becomes a rear pipe p2 for the rear axle and goes to the third branch C3 in the vicinity of the rear axle via the rear axle control valve Vr. The rear pipe p2 is branched at the third branch C3, one of which is a third high pressure pipe p3r connected to the high pressure chamber of the rear right hydraulic cylinder RSr, and the other is a fourth high pressure pipe p4h. Connected to the high pressure chamber of the cylinder RSh.
The hydraulic oil that has entered the hydraulic cylinders FSh, FSr, RSh, and RSr presses the piston Pi from the high-pressure chamber Cu to increase the vehicle height.
[0023]
Further, the hydraulic oil chambers Cs through the pistons Pi of the hydraulic cylinders FSh, FSr, RSh, and RSr are designed to retain the amount of oil that determines the vehicle height.
Each pressure oil chamber Cs is connected to the front right pressure oil chamber Cs on the front axle with the first return pipe q1r, and the front left pressure oil chamber is connected to the second return pipe q2h to return to the oil tank Gt. ing.
The first return pipe q1r and the second return pipe q2h are gathered at the first gathering point D1, become the gathering pipe q0, and enter the oil tank Gt via the front axle control valve Vf via the third gathering point D3. Connection is back. The same applies to the rear axle, and the return oil from the pressure oil chamber is gathered at the second gathering point D2, and is connected to the oil tank Gt via the rear axle control valve Vr via the third gathering point D3. .
[0024]
Also, the front axle wheel height adjustment switch SWf is connected to the front axle control valve Vf, and the rear axle wheel height switch SWr is connected to the rear axle control valve Vr by electric wires, and the vehicle height is transferred to each hydraulic cylinder FSh, FSr, RSh, RSr. It is controlled by oil supply.
[0025]
FIG. 8 shows the front axle 11 attached to the frame 2 and the front axle 11 of the front hydraulic cylinder FS, and FIG. 9 shows the state of the rear axle 12 attached to the frame 2 and the rear axle 12 of the rear hydraulic cylinder RS.
The fluid suspension is not necessarily limited to a hydraulic cylinder. For example, a diaphragm type air suspension as shown in FIG. 10 may be used in a vehicle type in which air pressure is easier to use than hydraulic pressure. FIG. 10 is for the rear axle, RSf indicates a rear front spring, and RSr indicates a rear rear spring.
[0026]
Here, the symbol Df indicates a front door, and Dr indicates a rear door. Moreover, the code | symbol E has shown the engine.
[0027]
The operation of the embodiment of FIGS. 1 to 4 and FIGS. 7 to 9 will be described.
The vehicle T having a low cab floor shown in FIGS. 1 to 4 has a low ground clearance due to the cab 1 being mounted on the front frame 2a having a ground clearance lower than that of the frame 2, so that the lift is easy. Become. In addition, the floor surface can be flattened with a margin in the height direction due to the low floor, the cab length can be increased, the operability is improved, and the living space is increased.
[0028]
The operation of the fluid suspension shown in FIGS. 7 to 9 will be described with reference to the flowchart of FIG.
In step S1, it is determined which axle height is to be changed. When changing the height of the front part of the vehicle, go to step S2. When changing the height of the rear part of the vehicle, the process goes to step S4. If the front and rear heights are to be changed simultaneously, go to step S3.
In step S2, the front left and right hydraulic cylinders FSh and FSr are operated via the front axle control valve Vf by the front vehicle height adjustment switch SWf in FIG. Next, the process goes to step S5.
In step S4, the rear left and right hydraulic cylinders RSh and RSr are operated via the rear axle control valve Vr by the rear vehicle height adjustment switch SWr in FIG. Next, the process goes to step S5.
In step S3, the front and rear left and right hydraulic cylinders FSh, FSr, RSh, and RSr are operated by the front and rear vehicle height adjustment switches SWf and SWr in FIG. Next, the process goes to step S5.
In step S5, it is determined whether to raise or lower the ground clearance of the front part of the vehicle, the rear part of the vehicle, or the entire vehicle. If it is to be raised, go to Step S7, and if it is to be lowered, go to Step S6.
In step S6, the hydraulic cylinder is shortened.
In step S7, the front or rear front hydraulic cylinder is extended. The vehicle posture of the vehicle T by the proper use of the above steps is shown in FIGS. In FIG. 11, steps S1, S3, and S6 have passed, and the vehicle height is lowered by shortening the front and rear hydraulic cylinders FSh, FSr, RSh, and RSr of all the cylinders. Therefore, the liftability is the best. However, the height of the obstacle that can be climbed is the lowest at H1, and the approach angle α1 is small, which is not suitable for traveling on rough terrain.
[0029]
In FIG. 12, steps S1, S3, and S7 have elapsed, and the front and rear hydraulic cylinders FSh, FSr, RSh, and RSr of all the cylinders are extended to increase the vehicle height. Therefore, the elevating / lowering performance is deteriorated. However, the height of the obstacle that can be ridden increases with H2, and the approach angle α2 also increases, which is suitable for traveling on rough terrain.
[0030]
FIG. 13 shows steps S1, S3, S6, and S7 that have elapsed simultaneously. The front part of the vehicle is raised and the rear part of the vehicle is lowered. The obstacle height that can be climbed is increased and the approach angle α3 is maximized. become. On the other hand, the liftability is the worst, and the departure angle γ indicating the poor ground contact and proximity of the rear end of the vehicle is minimized.
[0031]
FIG. 5 and FIG. 6 show another embodiment in which the cab is raised or lowered by the frame improvement, that is, the front end of the frame 2 is lowered.
FIG. 5 is formed so that the vertical offset of the coupling member 15A is eliminated and the coupling portion of the front frame 2A is inclined to lower the ground height.
In this way, the coupling member 15A is simplified and the weight is reduced, and the cab 1 can be mounted on a low floor.
[0032]
In FIG. 6, the hollow rectangular material 15Ba is coupled to the frame 2 so that the ground height of the front frame 2B is further lowered, and the front frame 2B is coupled to the hollow rectangular material 15Ba by the support plate 15Bb.
In this way, even when the frame 2 and the front frame 2B are not directly connected to each other, the cab 1 can be mounted on the floor with the hollow rectangular material 15Ba.
[0033]
【The invention's effect】
The effects of the present invention are listed below.
(1) Since a front frame having a ground clearance lowered by a coupling member is coupled to the front end portion of the frame, and the cab is mounted on the front frame having a low ground clearance, the floor ground clearance is lowered and the liftability is improved.
(2) Since the length of the front end of the frame can be freely increased, the inside of the cab can be widened, and the comfort of the passengers can be improved.
(3) Since the ground height of the cab can be lowered, the height of the ladder frame can be afforded, and a high-performance device can be mounted.
(4) Since the ground height of the cab can be lowered, the position of the center of gravity of the vehicle is lowered, and traveling stability and on-site work stability are increased.
(5) Since the front frame having a low ground clearance is coupled to the frame by a coupling member, a mass production frame can be used, which is technically difficult and can be easily manufactured without newly installing an expensive press die.
(6) In addition to the above-mentioned effects of lowering the floor, the vehicle front or rear can be freely moved up and down with the fluid suspension. If you want to drive on rough terrain, extend the hydraulic cylinder to raise the vehicle height. If you want to raise the front or rear of the vehicle, you can raise the front and lower the rear to increase the approach angle. . Further, with such a structure, the cab length can be increased, and the comfortability and workability in the cab are further improved.
[Brief description of the drawings]
FIG. 1 is an explanatory side view of a vehicle showing an embodiment of the present invention.
FIG. 2 is a side view of a ladder fire engine in which a ladder is mounted on the vehicle of FIG.
3 is a side view of the left side of the frame showing the frame shape of FIG. 1. FIG.
4 is a top view of FIG. 3;
FIG. 5 is a side view of the left side of the frame showing another frame shape.
FIG. 6 is a side view of the left side of the frame showing another frame shape.
FIG. 7 is a hydraulic suspension circuit diagram.
FIG. 8 is a side view showing a hydraulic cylinder for a front axle.
FIG. 9 is a side view showing a hydraulic cylinder for a rear axle.
FIG. 10 is a side view showing an air suspension.
FIG. 11 is a side view of the vehicle when the vehicle height is lowered by a hydraulic suspension.
FIG. 12 is a side view of the vehicle when the vehicle height is raised by a hydraulic suspension.
FIG. 13 is a side view of a vehicle when a front vehicle height is raised by a hydraulic suspension and a vehicle height is lowered after that.
FIG. 14 is a flowchart showing a method of changing the vehicle posture by a hydraulic suspension.
FIG. 15 is a vehicle side view for explaining the configuration of a conventional vehicle, obstacle overcoming ability, and approachability.
FIG. 16 is a side view of a front suspension with a laminated leaf spring mounted in FIG. 15;
17 is a side view of the rear suspension by the parent-child spring mounted in FIG.
[Explanation of symbols]
FOH, front overhang FS, front fluid suspension RS, rear fluid suspension T, vehicle 1 ... cab 2, frame 2a, front frame 2b, front end 3, front passenger seat 4 ... Rear passenger seat 8 ... Floor surface 11 ... Front axle 12 ... Rear axle 15 ... Coupling member

Claims (1)

  In the ladder fire engine equipped with the double cab (1) using the ladder type frame (2), the ladder type frame (2) is formed substantially flat from the front axle (11) from the front part to the rear end part, And a hollow rectangular material (15Ba) is combined with the front-end | tip part of a ladder type | mold frame (2), a front frame (2B) is combined with a support plate (15Bb) at the front part of this hollow rectangular material (15Ba), and a ladder type | mold frame The upper surface of the front frame (2B) is made lower than the lower surface of (2) so that both have a vertical difference, the double cab (1) is mounted on the front frame (2B), and the front axle (11) is the front hydraulic pressure In the suspension (FS), the rear axle (12) is suspended by a rear hydraulic suspension (RS), respectively, and the front and rear hydraulic suspensions (FS and RS) are respectively removed from the pump (G). Each of the front and rear hydraulic cylinders (FSh, FSr; RSh, RSr) is provided via a front axle control valve (Vf) and a rear axle control valve (Vr). ) Is connected to the front axle wheel height adjustment switch (SWf), and the rear axle control valve (Vr) is connected to the rear axle wheel height adjustment switch (SWr), and the front axle wheel height adjustment switch (SWf) and the rear axle wheel height are respectively connected. Adjusting the ground height by operating the adjustment switch (SWr) and simultaneously operating the front and rear hydraulic cylinders (FSh, FSr; RSh, RSr), and the approach by operating either the front or rear hydraulic cylinder A ladder fire engine characterized by having a function of selectively operating adjustment of an angle / departure angle.

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