JPH0347330A - Skid steer loader - Google Patents

Abstract

PURPOSE:To improve the follow-up property of the rise or the like of an engine, and prevent the engine failure, and prevent dangerous accidents from happening at the time of the failure of the engine by providing a control line, with an electricity controller, a motor cylinder, an alternator, a push button switch, and the like. CONSTITUTION:A control line is provided with the detecting means of an operation stroke, and the low idling position and high idling position of an accelerator lever 12 are previously set, and an electricity controller 15 for controlling the position of the accelerator lever via a motor cylinder 14 according to the input of stroke detecting signal is set. Then, according to an operation stroke quantity, the rotation of an engine 11 is quickly set. Besides, a joy stick 6A is provided with a push button switch 28, and the delay of the rise of the engine 11 is eliminated. Besides, an alternator 17 is set, and when the rotational frequency of the engine 11 comes to a specified value or lower, then operation signal is lowered, and the engine failure is prevented from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a cargo handling vehicle capable of super interlining turning (turning on the spot);
In other words, it relates to skid steer loaders.

2. Description of the Related Art As a conventional skid steer loader, the one described in Japanese Patent Application No. 63-214287 has been proposed, for example.

This skid steer loader basically consists of a vehicle body, two traveling devices installed on the vehicle body, and two driving devices that operate each traveling device.
one travel hydraulic drive device, two cargo handling devices provided on the vehicle body, two cargo handling hydraulic drive devices that operate each cargo handling device,
It consists of an engine, which is the power source for the travel hydraulic drive system and the cargo handling hydraulic drive system, and the engine, the two travel hydraulic drive systems, and the two cargo handling hydraulic drives are operated by operating two multi-directional lever switch devices provided on the vehicle body. An electrical control device is provided to control the device.

Problems to be Solved by the Invention However, in conventional skid steer loaders, the operating force of the multi-directional lever switch device is light, and even when operated,
The engine speed is due to the delay of the engine's accelerator lever mechanism and the speed at idling (approximately 11,000 RP).
) and rotation speed during work (1800-2500 RPM)
Due to the difference in speed, the engine does not follow up immediately, and if the work is stopped, the rotational speed drops to the idling speed, so there is a problem that the predetermined rotational speed cannot be obtained when necessary.

In addition, with multi-directional lever clutch devices, a small amount of force or movement produces a large command signal, so during driving or cargo handling operations (
There is a problem in which a sudden load is applied and a carrot stop (hereinafter referred to as engine stall) occurs.Furthermore, after the engine stalls, the travel control position of the travel hydraulic drive device remains the same as before the engine stalled, so it is difficult to start the engine immediately. The problem is that it starts moving as soon as it starts, which is extremely dangerous.

The present invention solves the above-mentioned problems related to carrots, and improves the ability of the engine to follow uphill slopes, prevents engine stalls, and prevents the risk of engine stalls occurring in hidden spots. The purpose is to provide a steer loader.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a vehicle body and a device provided on the vehicle body. : Two traveling devices, two traveling hydraulic drive devices that operate each traveling device, and two cargo handling devices provided on the vehicle body.
Two cargo handling hydraulic drive devices that operate each cargo handling device, an engine that is a power source for the traveling hydraulic drive device and the cargo handling hydraulic drive device, and a multi-directional lever switch device for controlling the two traveling devices and cargo handling device provided on the vehicle body. A skid steer loader comprising: a detection means for detecting an operation stroke by inputting operation signals of the two multi-directional lever switch devices; and a drive device for an actuation lever that controls the rotational speed of the engine. , a low idling position and a high idling position of the accelerator lever are set in advance, and the drive device is moved to this stroke position, low idling position or high idling position in response to input of a stroke start signal from the detecting means. A control means for controlling the position of the accelerator lever is provided.

Furthermore, in addition to the structure of the first invention, the skid steer loader of the second invention is provided with a switch on the vehicle body, and when the control means inputs an operation signal of the switch, the control means increases the rotational speed of the engine. The system is designed to control the position of the accelerator lever.

Further, the skid steer loader of the third invention includes a rotation speed detection device that detects the rotation speed of the engine, and when the rotation speed detected by the rotation speed detection device is below a predetermined value, the multi-directional lever switch device is operated. The device is characterized in that a limiting means for reducing the signal is provided.

Further, the skid steer loader of the fourth invention includes a rotation speed detection device that detects the rotation speed of the engine, two detection means that detects the travel control position of each traveling hydraulic drive device, and a rotation speed detection device that detects the rotation speed of the engine. and a control means for controlling each travel hydraulic drive device so that each travel control position becomes a forward/reverse neutral position using the travel control position signal of each detection means as a feedback signal when the detected rotation speed is zero. It is characterized by:

Operation According to the above structure, when the multi-directional V-par switch device is operated, the accelerator lever position is controlled to this operation stroke position, and when the operation is no longer performed, it is set to the high idling position, for example, and then to the low idling position. and the accelerator lever position is controlled. By having a high idling position, it is possible to quickly respond to the operating stroke amount.

Further, according to the configuration of the second invention, the engine speed is increased by operating the switch, and the multi-directional lever switch device is operated after the engine speed is increased, thereby eliminating the delay in start-up.

Furthermore, with the configuration of the third invention, when the engine speed falls below a predetermined value, the operation signal of the multi-directional lever switch device is reduced, reducing the burden of traveling and cargo handling operations, thereby preventing engine stalling. be done.

Further, according to the configuration of the fourth invention, when the engine speed is zero, the travel control position of each travel hydraulic drive device becomes a neutral position for forward and reverse travel, thereby preventing the risk of the engine starting and causing the vehicle to go into a traveling state.

Example An embodiment of the present invention will be described below based on the drawings.

FIG. 1 is a side view of a skid steer loader showing an embodiment of the present invention, and FIGS. 2 and 3 are diagrams of essential parts of a control system and a block diagram of an electric control device of the same skid steer loader.

The skid steer loader 1 is a cargo handling vehicle that is capable of super interlining turning using left and right wheels 2 that are driven independently.As shown in FIG. 4, seat bar 5 for protection in the event of a collision
by attaching a wheel 2 and operating two multi-directional lever switch devices (hereinafter referred to as joysticks) 6.
is driven and moves by itself, and the packet cylinder 7 and boom cylinder 8 of the cargo handling hydraulic drive system drive the packet 9 and the boom 10! 11111 and is configured to carry out cargo handling.

The configuration of the control system will be explained based on FIG.

The engine 11 has its rotational speed and output torque controlled according to the amount of operation of the accelerator lever 12, and
The par 12 is connected to an electric cylinder 14 via an electromagnetic clutch 13.
The electric cylinder 14 is controlled by an electric control device 15. The lever position of the accelerator lever 12 is detected by a potentiometer 16 and input to the electric control device 15, and the rotation of the engine 11 is detected by an alternator 17 and input to the electric control device 15. The electromagnetic clutch 13 is always energized, and when an emergency button (not shown) is pressed, it becomes de-energized, the accelerator lever 12 returns to the zero rotation speed position by the spring 18, and the engine 11 stops.

In addition, the rotational force of the carrot 11 is transmitted to the left and right HST (hydrostatic) pumps 19L and 19R and the main pump 20, and the left and right H5T pumps 19L
.

19R converts the hydraulic oil into high-pressure fluid and sends it to the left and right hydraulic drive motors 21L and 21R, and the hydraulic drive motors 21L and 21R take out the hydraulic fluid and drive the left and right wheels 2L and 2R independently with the psychodynamic torque. ing.

HST pumps 19L and 19R are steering lever 22L.

The direction and discharge amount of the hydraulic oil are determined by the position of the steering lever 22R from the neutral position.
The running direction and speed of the skid steer loader I are controlled by operating L and 22R. Steering lever 22L
, 22R are electric cylinders 23L, respectively.

Driven by 23R and steering lever 22L.

The position of 22R is the position of these electric cylinders 22L, 22R1-
The positions of the steering levers 22L and 22R are fed back to the electric control device 15 by potentiometers 24L and 24R, respectively.

Finally, the rotations of the hydraulic drive motors 21L and 21R, that is, the rotations of the wheels 2L and 2H, are detected by rotary encoders 25L and 25R, respectively, and fed back to the electric control device 15.

The pressure oil of the t1 main pump 20 is controlled/<
A/ is led to 26, 27, and the controller A/
/<Lupu26.27 spool is 1! By being moved from the neutral position by the air control device 15, pressure oil is sent to the rod side or tail side of the packet cylinder 7 and boom cylinder 80, and the packet 9 and boom 10 are raised or lowered.

Further, the joysticks 6A and 6B are, for example, a fourth joystick.
As shown in Figures fat and ), the operating direction (forward, reverse, upward, downward) is determined by the direction in which the lever is operated.
The operating speed is determined by the stroke amount from the neutral position, and the joystick 6A.

The respective X coordinates and X coordinates of 6B are input to the electric control device 15. Further, a push button switch 28 is provided at the head of the joystick 6A, and the operating number of the push button switch 28 is also input to the electric control device 15.

The electric control device 15 will be explained based on the block diagram of FIG.

Joystick 6A, 6B operation signals X, IX,, Y
, 1y are absolute value converters 31A, 31B, 31, respectively.
C and 31D, it is converted into an absolute value, that is, converted into a stroke amount from the neutral position, and input to the high value priority circuit 32, where the maximum stroke amount l is detected.

As shown in FIG. 5, the electric control device 15 is programmed in advance to set the accelerator lever position z of the engine 11 to a low idling position 2, which corresponds to the conventional idling position. and a high idling position z, and a maximum stroke amount l and these idling positions fil zl.

2, a target fiL of the accelerator lever position is formed.

The maximum stroke amount l is positive, that is, joystick 6
The comparator 33 detects that A and 6B are operated, and then the comparator 33 operates to turn on the relay RY2.

Also, since the comparator 33 is not operating, the timer 34
is activated, and when the timer 34 counts up, the relay RY3i is turned on. Sunarichi, timer 3
4 is turned on when a predetermined period of time has elapsed since the joysticks 6A and 6B are not operated, and VRY3 is turned on. The target value is when VRY2 is on.
High idling position 2 and maximum stroke m1tl - value added by adder 35 (l 10), high idling position Hz when relay RY2 is off and relay RY3 is off,
When relay RY2 is off and relay RY3 is on, the low idling position @z1 is set. In other words, when operating joysticks 6A and 6B, (1+z,)
, joystick 6A.

68t - Joysticks 6A, 6B remain 21 for a while after they are no longer operated, and the timer 34 operates.
It is set to 21 when it is no longer operated.

The target value is input to the rate of change limiter 57. The rate of change limiter 57 is configured to change the target value even if the difference between the target value, which is the bluff manual input of the adder 36, and the current target fi (output value of the rate of change limiter 57) K, which is the negative input of the adder 36, is large. Even if the value suddenly changes, the input of the integrator 37 is suppressed by the upper limiter 38 and the lower limiter 39, thereby preventing the sudden change to the current target value. Now, if the limit value of the upper limiter 38 is α and the limit value of the lower limiter 39 is β, then β < 0 × α, 1 β 1 (set as 1 α 1,
Currently, the rate of change is set so that when increasing the target [K, that is, when increasing the rotation speed of the engine 11, it is rapid, and when decreasing it, it is gradually. The relay RYI is turned on by the operation signal of the push button switch 28, that is, the input of the integrator 37 is set to J (>0) by turning on the manual operation relay RYI, and the current date of the accelerator V bar position is increased by 41 mK. Joystick 6A.

The rotation speed of the engine 11 is increased independently of the operation of 6B.

Currently target ff1K is potentiometer 1 of engine 11
The deviation is taken by the adder 40 from the nine actual accelerator V bar position detected at 6, and this deviation is input to the PID controller 41, and the output of the PID controller 41 is input to the drive unit 42, and the current target value is added to the accelerator 40. The electric cylinder 14 is driven so that the tvv bar positions match, and the current target value K
The rotation speed of the engine 11 is controlled to a rotation speed corresponding to .

Further, the rotation of the engine 11 is detected by the alternator 17, and the rotation (pulse) signal is converted into a rotation speed by a counter 43 and inputted to a comparator 44. has been detected. When engine stall is detected by comparison device, relay RY4
turns on. In addition, two function generators 45 and 46 which receive the output rotation speed of the counter 43 as input are provided, and as shown in FIGS. 6 and 7, joysticks 6A and 6B are provided.
Operation signals X, eX! Multiplier 4 that multiplies wy, −y,
Constants 7A to 47D are generated. Multipliers 47-47
The constants a and la of D are determined when the rotational speed is a predetermined rotational speed δ2. l,
If it is less than 1, then the operation signal x, ・x2・y
, ·y, that is, the traveling/cargo handling command, is reduced by multiplication, and the load on the engine 11 is determined to be reduced.

Joystick 6A, 6B operation signal X, *XS%
In other words, multipliers 47A and 47B that receive travel commands as inputs.
The outputs (multiply values) of HST pumps 19L and 1 are respectively
9R button V yometer 24L, detected by 24R, fc actual steering lever position signal, rotary encoder 25L.

Rotation of wheels 2L and 2H output from 25R (Pal 7,
) 48L converts the signal into the rotational speed as input.
.

Control of steering levers 22L and 22R using the output rotation speed signal of 48R as a feedback signal 49
L.

49R (D is input as the target value, and the controllers 49L, 49
The output of R is input to the drive units 50L and 50R, and the drive unit 50L.

At 50R, the electric cylinder 23L is set so that the positions of the steering levers 22L and 22R become the multiplier values of the multipliers 47A and 47B.

23R is driven, the wheels 2L and 2R rotate, and the skid steer loader 1 travels. Also, when relay RY4 turns on at the tth moment of engine stall, steering lever 22L
, 22R and the HST pumps 19L, 19R's potentiometers 24L, 24R and detected by the nine steering V-par positions are input from adders 51L, 51R. is input to the electric cylinder 23L of the steering lever 22L, 22R,
23R is driven, steering levers 22L, 22R
is controlled so that it is in the neutral position.

In addition, the operation signals y of the joysticks 6A and 6B.

y, - that is, a multiplier 47C14 that receives the cargo handling command as input.
7111) The output (multiplication [) is input to the controllers 53.54 of the pool 10 and the packet 9, respectively, and
The output of drive unit 55.4 is input to drive unit 55.56.
At step 56, the spools of control pulp 26, 27 are slid from the neutral position so that the multipliers 47C and 47D have the multiplied values, and the boom 10 and packet 9 are raised or lowered.

In this way, the rotation speed of the engine 11 can be rapidly increased by increasing the limit value α of the upper limiter 38 by operating the joysticks 6A and 6B.
Furthermore, while the joysticks 6A and 6B are being operated continuously (while the timer 34 is not operating), the rotation speed of the engine 11 is held at a high idling position while gradually decreasing, so that the joysticks 6A and 6B are not operated. The rotation speed of the engine 11 can be adjusted immediately.

Also, by operating the push button switch 28, the engine 1
1 rotation speed can be increased, and running and cargo handling operations can be started from that rotation speed by operating the joystick 6, so problems such as startup delays can be completely solved.

Further, when the engine 110 rotational speed becomes equal to or lower than the predetermined rotational speed δ, δ3, the joysticks 6A, 6B operation signals X, I This makes it possible to prevent engine stalling.

Further, in the event that the engine stalls, the steering levers 22L and 22R are returned to the neutral position, thereby preventing the risk of the engine 11 immediately starting running after the engine stalls.

Effects of the Invention As described above, according to the present invention, the accelerator lever has a high fitting position, and by controlling the accelerator/L/V par to this high idling position, the engine's operating stroke amount can be adjusted. The rotation speed can be quickly adjusted.

Further, according to the second invention, the engine speed can be increased by operating the switch independently of the multi-directional lever switch device, and after the engine speed has been increased, the engine speed can be increased by operating the switch. It can run and handle cargo, and it can solve problems such as engine start-up delays.

Furthermore, according to the third invention, when the rotation speed of the carrot is below a predetermined value, the multi-directional V reduces the operation signal of the single switch device, thereby reducing the burden on the carrot during traveling and cargo handling work. This can prevent engine stalls.

According to the fourth invention, when the engine speed is zero, the travel control position of each travel hydraulic drive device is set to the neutral position for forward and reverse travel, thereby preventing the risk of the vehicle immediately entering the travel state by restarting the engine. It can be prevented.

[Brief explanation of drawings]

The drawings show an embodiment of the skid steer loader according to the present invention, in which Fig. 1 is an external side view, Fig. 2 is a main part configuration diagram of the control system, Fig. 3 is a block diagram of the electric control device, and Fig. 3 is a block diagram of the electric control device. Figure 4 (a
l and Tbl are joystick operation explanatory diagrams, 5th
The figure is an explanatory diagram of the position of the accelerator lever, and FIGS. 6 and 7 are characteristic diagrams of the function generator, respectively. l...Skid steer loader, 2...Wheels (traveling device), 6...Multi-directional V-par switch device (joystick), 7...Packet cylinder (cargo handling hydraulic drive device), 8...Boom Cylinder (cargo handling hydraulic drive device),
9... Packet (cargo handling device), 1o... Boom (cargo handling bag, 11... Engine, 12... Accelerator lever-14... Electric cylinder, 15... Electricity, control device, 16 ... Potentiometer, 17... Alternator (rotating aljBli location), 19... H5T pump (
traveling hydraulic drive device), 21...hydraulic drive motor,
··Push-button switch.

Claims (1)

[Claims] 1. A vehicle body, two traveling devices provided on the vehicle body, two traveling hydraulic drive devices that operate each traveling device, two cargo handling devices provided on the vehicle body, and operating each cargo handling device. A skid equipped with two cargo-handling hydraulic drive systems for transporting the cargo, an engine as a power source for the traveling hydraulic drive system and the cargo-handling hydraulic drive system, and a multi-directional lever switch device for controlling the two travel systems and the cargo-handling system provided on the vehicle body. The steer loader includes a detection means for detecting an operation stroke by inputting operation signals of the two multi-directional lever switch devices, an accelerator lever driving device for controlling the rotational speed of the engine, and a detection means for detecting an operation stroke by inputting operation signals of the two multi-directional lever switch devices, an accelerator lever driving device for controlling the rotation speed of the engine, and a detecting means for detecting an operation stroke by inputting operation signals of the two multi-directional lever switch devices; An idling position and a high idling position are set in advance, and the accelerator lever position is controlled to this stroke position, a low idling position, or a high idling position via the drive device in response to input of a stroke detection signal from the detection means. A skid steer loader equipped with control means. 2. Claim 1, wherein a switch is provided on the vehicle body, and the control means controls the position of the accelerator lever in the direction of increasing the engine speed when an operation signal of the switch is input.
The skid steer loader described. 3. Two traveling devices installed on the vehicle body, two traveling hydraulic drive devices that operate each traveling device, and two traveling devices installed on the vehicle body.
two cargo handling devices, two cargo handling hydraulic drive devices that operate each cargo handling device, an engine as a power source for the travel hydraulic drive device and the cargo handling hydraulic drive device, and two cargo handling devices provided on the vehicle body for controlling the cargo handling device and The skid steer loader is equipped with a multi-directional lever switch device, and includes a rotation speed detection device that detects the rotation speed of the engine, and when the rotation speed detected by the rotation speed detection device is below a predetermined value, the multi-directional lever switch device detects the rotation speed of the engine. A skid steer loader equipped with a limiting means for reducing the operation signal of a directional lever switch device. 4. A vehicle body, two traveling devices provided on the vehicle body, two traveling hydraulic drive devices that operate each traveling device, two cargo handling devices provided on the vehicle body, and two cargo handling hydraulic drives that operate each cargo handling device. A skid steer loader comprising a device, an engine as a power source for the traveling hydraulic drive device and the cargo handling hydraulic drive device, and a multi-directional lever switch device for controlling two traveling devices and the cargo handling device provided on the vehicle body, a rotation speed detection device that detects the rotation speed of the engine; and two detection means that detect the travel control position of each of the travel hydraulic drive devices;
When the rotation speed detected by the rotation speed detection device is zero, each travel hydraulic drive device is controlled using the travel control position signal of each detection means as a feedback signal so that each travel control position is a neutral position for forward and reverse travel. A skid steer loader is provided with a control means for controlling the skid steer loader.