JP2937736B2 - Emergency steering mechanism for multi-axle vehicles with abnormal input limiting mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The steered shafts each have a power cylinder, and the power cylinder disposed on the rear shaft is connected to a booster, and the steered shaft operates synchronously with a steering linkage. The present invention relates to a steering device for a multi-axle vehicle in which an input link to the booster is provided with an abnormal input limiting mechanism and a plurality of axes can be steered.

[0002]

2. Description of the Related Art FIG. 1 shows an embodiment of the present invention. First, known parts will be described. The figure shows 6 axes 12
The three wheels 1, 2 and 3 on the left side in the figure and the two axes 5 and 6 on the right side in the figure are steered in opposite phases, and the fourth shaft 4 from the left in the figure is not steered. It has become.

[0003] The steering wheel 35 is connected to a semi-integral steering (hereinafter abbreviated as SIPS) 36 for controlling a hydraulic system and a link system.

In the case of a hydraulic system, oil stored in a reservoir tank 7 is supplied to control valves 11 and 1 through oil pumps 9 and 10 driven by an engine 8.
The oil is sent to the SIPS 36 and the spool valve portion of the booster 13 via 2 respectively, and when the spool valve portion is in a neutral state, that is, when the vehicle is in a straight running state, the oil does not proceed further but makes a U-turn at the spool valve portion. , Is returned to the reservoir tank 7. 3 to 5
Shows the position of the spool valve portion V, FIG. 3 shows a neutral state,
FIG. 4 shows a right steering state, and FIG. 5 shows a left steering state.

When the steering wheel 35 is rotated to the right or left, the spool valve portion V is brought into the state shown in FIG. 4 or 5 and the oil is supplied to the power cylinders 21, 22, 23, 2
5 and 26, the oil which has filled the power cylinder at the same time is supplied to the reservoir tank 7 via the spool valve.
It is to be returned to. The above operation is the same even when the stroke of the booster 13 or the like is performed, and the booster 13 also functions as a booster by sending oil to the main body by itself.

[0006] Regarding the link system, the pitman arm 14 is turned into a swinging motion via the SIPS 36 by rotating the steering wheel 35, and is connected to the idler arm 16 that rotates around the fulcrum 19 via the pitman link 15. To steer the front shaft 1. The swinging motion of the idler arm 16 is
The front shaft 2 is steered by changing the swinging motion of the idler arm 18 around the fulcrum 0.

At the same time, the idler arm 18 is
The operating point of the spool valve portion V is set to an input link 44 (not shown) with an input link 44 and an abnormal input restriction mechanism 40 interposed.
Connect at 3 'to convert swinging motion to spool valve stroke.

By moving the spool valve of the booster 13, the booster body receives the supply of oil and functions as a booster as described above, and the end of the piston rod 13a is supported by a frame (not shown). The expansion and contraction action of 13 changes the idler arm 27 into a swinging motion and steers the rear shaft 3.

Incidentally, the abnormal input limiting mechanism 40 is used when a wheel on the rear axle gets stuck in, for example, a rut or a groove and is locked so that it cannot be steered during multiple steering in a multi-axle vehicle in which a load is not concentrated on one axle. In order to protect the linkage by limiting the input, an example in which the input links 43 and 44 connected to the booster are interposed is known as a known technique from Japanese Utility Model Laid-Open No. 5-41617.

Further, the rear shafts 5, 6 link the swinging motion of the idler arm 27 and the idler arms 28, 29, 3
.. Are steered in the opposite phases to the front shafts 1, 2 and the rear shaft 3, respectively.

The above-mentioned link system operation SIPS 36
And the booster body 13 and the power cylinders 2, 21, 2
By operating the steering wheels 2, 23, 25 and 26 as a booster and rotating the steering wheel 35 with a small input load, it is possible to obtain an output sufficient to steer each axis.

[0012]

However, the abnormal input limiting mechanism turns the front shaft when the rear shaft has an abnormality,
Although it is possible to escape from the rut, if the front axle is abnormal and the wheels are locked, the rear axle will also be unable to steer, making the vehicle difficult to advance or retreat.

Therefore, according to the present invention, for example, when the rear wheel is stuck in a rut and steering of the rear wheel becomes impossible, only the front wheel is steered,
By adding a mechanism to the mechanism that can escape the rut, it is possible to urgently steer the rear wheel and escape the rut etc. even if the front wheel gets stuck in the rut, for example. is there.

[0014]

According to the present invention, the steered shafts (1, 2, 3, 5, 6) are respectively provided with power cylinders (21 to 21).
26), and the power cylinders (23, 25, 26) arranged on the rear shafts (3, 5, 6) are connected to a booster (13), and the turning shafts (1, 2, 3,
5 and 6) are operated synchronously by a steering linkage, and a steering device for a multi-axle vehicle in which a plurality of axes can be steered by interposing an abnormal input limiting mechanism (40) on an input link to the booster (13); Abnormal input restriction mechanism (40)
The end of the input link (43) interposed therebetween is pivotally connected to a part of an idler arm (50) having the fulcrum (50a) as a fulcrum.
One end (51a) of the idler link (51) is connected to the spool valve portion (V) of the booster (13), and the idler arm (5) is further connected to the idler arm (5).
0), the piston rod (52) of the emergency actuator (52) having one end (52b) pivotally attached to the frame.
The end of a) is pivotally mounted, and the left and right pressure chambers (52b, 52e) of the emergency actuator (52) are connected to the air reservoir (52) by piping (L1, L2) via electromagnetic valves (60, 62), respectively. 70).

[0015]

According to the present invention, each of the steered shafts has a power cylinder as described above, and the power cylinder disposed on the rear shaft is connected to a booster, and the steered shafts are synchronized by a steering linkage. In a multi-axle vehicle steering system in which a plurality of axes can be steered with an input limiting mechanism interposed in an input link to the booster, when all wheels of a front axle are locked, an emergency By operating the actuator, the rear wheel can be steered.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The description of the same components as those of the related art in FIG. 1 is omitted.

First, in the conventional example, the tip of an input link 43 '(not shown) provided with the abnormal input limiting mechanism 40
3, the end of the input link 43 provided with the abnormal input restriction mechanism 40 is partially connected to the idler arm 50 having the fulcrum 50a as shown in FIG. One end 51 a of an idler link 51 is pivotally connected to the tip of the idler arm 50, and the other end 51 b of the idler link 51 is connected to a spool valve portion V of the booster 13.

Further, one end 5 is provided in the middle of the idler arm 50.
The end of the piston rod 52a of the emergency actuator 52, which is pivotally connected to a frame (not shown), is pivotally connected to the end 2b. The left and right pressure chambers 5 of the emergency actuator 52
2d and 52e communicate with the air reservoir 70 by piping L1 and L2 via electromagnetic valves 60 and 62, respectively. Hereinafter, the operation of the present application will be described.

Therefore, in an emergency, for example, when only the front axle is stuck in a deep rut and the wheels are locked, the solenoid valve 60 or 62 is operated by a switch (not shown) and either of the pressure chambers 52d or 52e is operated. Crab is filled with compressed air, and the booster 13 is operated via the piston rod 52a, the idler arm 50, and the idler link 51, and the link of the rear shaft and the idler arms 27, 28,
The rear shafts 4, 5, 6 are steered via 29, 31.

[0020]

Since the present invention is constructed as described above, for example, the load difference generated when the rear wheel is steered when the rear wheel is stuck in the rut is determined by the abnormal input limiting mechanism 4.
0 is absorbed by acting in a direction to reduce one of the built-in springs 45 and 46, protects the link group after the booster 13 from an excessive load, and only the front wheel is stuck in a deep rut, and the wheel is locked. In the case of an emergency such as in the case of, the emergency actuator is operated, and the wheels of the rear shafts 4, 5, and 6 can be temporarily steered, so that the mobility is greatly improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment according to the present invention.

FIG. 2 is a detailed view of a main part of an embodiment according to the present invention.

FIG. 3 is an explanatory view when a spool valve portion is at a neutral position.

FIG. 4 is an explanatory view when the spool valve unit is in a right-turning state;

FIG. 5 is an explanatory diagram when the spool valve unit is in a left-turning state;

[Explanation of symbols]

1, 2, ... front shaft 3, 4, 5, 6 ... rear shaft 7 ... reservoir tank 8 ... engine 9, 10 ... oil pump 11, 12 ... control valve 13 ...・ Booster 14 ・ ・ ・ Pitman arm 15 ・ ・ ・ Pitman link 16,18 ・ ・ ・ Idler arm 17 ・ ・ ・ Middle link 19,20,32 ・ ・ ・ Support point 21,22,23,25,26 ・ ・ ・ Power Cylinders 27, 28, 29, 31 Rear link and idler arm 35 Steering wheel 36 SIPS 40 Abnormal input limiter 43, 44 Input link 50 Idler Arm 51 ・ ・ ・ Idler link 52 ・ ・ ・ Emergency actuator 60,62 ・ ・ ・ Electromagnetic valve 70 ・ ・ ・ Air reservoir

Claims (1)

(57) [Claims] The steering shafts (1, 2, 3, 5, 6) each have a power cylinder (21 to 26) and a rear shaft (3, 2).
The power cylinders (23, 2
5, 26) are connected to a booster (13), and the steered shafts (1, 2, 3, 5, 6) are operated synchronously by a steering linkage to provide an input link to the booster (13). In a steering device for a multi-axle vehicle in which a plurality of axes can be steered with an abnormal input restriction mechanism (40) interposed therebetween, the end of the input link (43) interposed with the abnormal input restriction mechanism (40) is (50a). Idler arm as a fulcrum (50)
One end (51a) of an idler link (51) is pivotally connected to a tip of the idler arm (50), and the other end (51b) of the idler link (51) is connected to a booster (13). And an end of a piston rod (52a) of an emergency actuator (52) having one end (52b) pivotally connected to the frame in the middle of the idler arm (50). And the left and right pressure chambers (52) of the emergency actuator (52).
b, 52e) are emergency steering mechanisms for a multi-axle vehicle, characterized in that they are in communication with the air reservoir (70) by piping (L1, L2) via electromagnetic valves (60, 62), respectively.