JP2004359414A - Engine output controller for cargo loading/unloading vehicle and cargo loading/unloading vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine output controller for a cargo loading/unloading vehicle capable of increasing the number of revolutions of an engine and achieving the maximum shaft torque when loading and unloading a cargo even in the cargo loading/unloading vehicle limiting the maximum speed and to provide the cargo loading/unloading vehicle. <P>SOLUTION: This engine output controller for the cargo loading/unloading vehicle capable of suppressing the maximum speed of the cargo loading/unloading vehicle by regulating a degree of opening of an electronic control throttle 23 includes a vehicle speed detection means 30b for detecting speed of the cargo loading/unloading vehicle and a cargo loading/unloading determining means 30c for determining the cargo loading/unloading work by detecting that vehicle speed is zero from an output of the vehicle speed detection means 30b. When the cargo loading/unloading determining means 30c detects the cargo loading/unloading work, regulation of degree of opening of the electronic control throttle 23 is released to achieve the maximum shaft torque of the engine. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an engine output control device of a cargo handling vehicle (forklift) capable of controlling an engine speed at which a shaft torque is maximized during a cargo handling operation in a cargo handling vehicle (forklift) in which the maximum speed is suppressed. The present invention relates to a cargo handling vehicle provided with a simple engine output control device.
[0002]
[Prior art]
2. Description of the Related Art In an industrial vehicle such as a conventional cargo handling vehicle, a loading wheel is driven by an engine, and a loading cylinder is operated using discharge pressure oil of a hydraulic pump driven by the engine to perform a loading operation. The cargo handling vehicle is provided with an accelerator pedal, and the traveling speed changes according to the depression angle of the accelerator pedal (accelerator angle). In addition, the cargo handling vehicle is provided with a maximum vehicle speed control device that regulates the maximum speed of the engine and controls the maximum speed for the purpose of preventing an accident when traveling on the factory premises. For example, the maximum vehicle speed control device controls the engine speed by fixing the throttle opening even if the accelerator pedal is depressed so that the vehicle speed corresponding to the target speed does not exceed the maximum vehicle speed. And control the vehicle speed.
[0003]
Some cargo handling vehicles are provided with an optical sensor to detect the brightness of the cargo handling work place and to control the traveling speed to be reduced when the cargo handling work place is dark. For example, as shown in FIG. 2A, the optical sensors 5 are attached to the upper surface of the head guard 2 of the cargo handling vehicle 1, the top and both sides of the mast 3, and both sides of the cab panel 4, respectively. The control device detects the ambient brightness from the amount of light received by the optical sensor 5 and limits the vehicle speed. As shown in FIG. 2 (b), the control device of the cargo handling vehicle 1 determines the surrounding brightness and, when the brightness exceeds a predetermined threshold TH, does not limit the vehicle speed but reaches the limit speed M. However, when the surrounding brightness is equal to or less than a predetermined threshold value TH, the maximum vehicle speed is limited in proportion to the brightness. For example, if the surrounding brightness is S, the maximum vehicle speed is N (for example, see Patent Document 1).
[0004]
[Patent Document 1] Japanese Patent Application Laid-Open No. 2001-278599 (Full text of the specification, all drawings)
[0005]
[Problems to be solved by the invention]
However, in a conventional cargo-handling vehicle, the driving wheels are driven by the engine, and the cargo-handling cylinder is operated by using the discharge pressure oil of a hydraulic pump driven by the engine. In some cases, the maximum number of revolutions of the engine is limited, and the required torque cannot be obtained during the cargo handling work, which may hinder the cargo handling work.
[0006]
The present invention has been made in view of the above-described problems, and even in a cargo-handling vehicle configured to limit the maximum speed, at the time of cargo-handling work, the rotational speed of the engine is increased to maximize the shaft torque. It is an object of the present invention to provide an engine output control device for a cargo handling vehicle and a cargo handling vehicle.
[0007]
[Means for Solving the Problems]
SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to an engine output control apparatus for a cargo handling vehicle that controls the maximum speed of the cargo handling vehicle by restricting the throttle opening of an electronically controlled throttle to suppress the maximum speed. ,
Vehicle speed detecting means for detecting the speed of the cargo handling vehicle;
Loading / unloading determining means for detecting that the vehicle speed is zero from the output of the vehicle speed detecting means and determining that the loading operation is performed,
An engine output control device for a cargo-handling vehicle, wherein when the cargo-handling determination means detects a cargo-handling operation, the restriction on the throttle opening of the electronically-controlled throttle is released to maximize the shaft torque of the engine.
[0008]
According to the first aspect of the present invention, there is provided an engine output control device for a cargo handling vehicle that restricts the maximum speed of the cargo handling vehicle to the maximum speed by regulating the throttle opening of the electronically controlled throttle. When the vehicle speed detecting unit detects that the vehicle speed is zero, the cargo handling determining unit determines that the cargo handling vehicle performs the cargo handling operation, and at this time, the electronic control unit controls the amount of air to the engine. The control is performed so that the throttle opening of the control throttle can be adjusted to the maximum, so that there is no shortage of power at the time of cargo handling and there is no hindrance to cargo handling work. This vehicle speed detecting means uses a signal from a vehicle speed sensor that detects the rotation of a drive shaft that drives the drive wheels, detects that the vehicle speed is definitely zero, and determines that it is a cargo handling operation. .
[0009]
According to a second aspect of the present invention, there is provided an engine output control device for a cargo handling vehicle that controls the maximum speed of the cargo handling vehicle by restricting the throttle opening of the electronically-controlled throttle to suppress the maximum speed.
Maximum speed control means for controlling so as to suppress the maximum vehicle speed of the cargo handling vehicle,
Vehicle speed detecting means for detecting the speed of the cargo handling vehicle;
Cargo handling determining means for detecting that the vehicle speed is zero from the output of the vehicle speed detecting means and determining that the work is cargo handling work;
Switching control means for releasing the restriction on the maximum vehicle speed by the maximum speed control means and releasing the restriction on the throttle opening of the electronically-controlled throttle when the loading determination means detects the loading operation. 1 is an engine output control device of a loading vehicle.
[0010]
According to a second aspect of the present invention, there is provided an engine output control device for a cargo handling vehicle that suppresses the maximum speed by electronically controlling a throttle opening of a throttle to control the maximum speed of the cargo handling vehicle. A determination unit, and a switching control unit,
The maximum speed control means has a control function of controlling the maximum vehicle speed of the cargo handling vehicle, the vehicle speed detection means detects the vehicle speed of the cargo handling vehicle, and the cargo handling determination means detects the vehicle speed from the output of the vehicle speed detection means when the vehicle speed is zero. Based on this, it is determined that it is a cargo handling operation, the switching control means releases the regulation of the maximum vehicle speed by the maximum speed control means, and controls so that the throttle opening of the electronic control throttle can be maximized. In addition, the power shortage due to the decrease in the output of the shaft torque due to the shortage of the engine speed at the time of cargo handling can be resolved so that the cargo handling work is not hindered.
[0011]
According to a third aspect of the invention, there is provided a cargo handling vehicle including the engine output control device for a cargo handling vehicle according to the first or second aspect.
[0012]
According to the third aspect of the present invention, even if the vehicle is a cargo handling vehicle that limits the maximum vehicle speed, an engine output control device that can control the maximum rotation speed of the engine by switching between running and loading is provided. Even if it is, it is a cargo handling vehicle that can automatically determine the cargo handling work, and at the time of cargo handling work, can increase the engine speed and maximize the shaft torque. The required output can be obtained according to the operation of the accelerator petal, and there is an effect that there is no uncomfortable feeling and the cargo handling work can be performed.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of an engine output control device for a cargo handling vehicle and a cargo handling vehicle according to the present invention will be described with reference to FIG. FIG. 1 is a schematic system diagram showing an engine output control device for a cargo handling vehicle according to the present invention.
[0014]
As shown in FIG. 1, the cargo handling vehicle drives the drive wheels 11 and drives the hydraulic pump 12 to operate the cargo handling lever 13 by the engine 10 using gasoline or LPG (liquefied petroleum gas) as fuel. Accordingly, the discharge pressure oil is guided to the cargo handling cylinder, and the fork 15 of the mast 14 is moved up and down to perform the cargo handling work.
[0015]
The engine 10 includes a fuel supply system using gasoline or LPG (liquefied petroleum gas) as a fuel, an intake system for sending air required for combustion, and an exhaust system for sending combustion gas to the atmosphere. An electronic control system for controlling fuel injection is provided. In the fuel supply system (gasoline), a fuel supply pipe from a fuel tank 17 is connected to an injector 18 mounted on one end of an intake pipe 16. In the fuel supply system (LPG), a vaporizer 20 is supplied from a gas cylinder 19. The fuel supply pipe which has been passed through is connected to a fuel injector 22 mounted on the venturi 21. At the other end of the intake pipe 16, a venturi 21 and an electronically controlled throttle (hereinafter, referred to as an electronically controlled throttle) 23 are provided. An oxygen sensor 24 is provided in a pipe of the exhaust system, and a catalyst 25 for purifying the combustion gas and a manifold filter 26 are mounted. In the intake system, an air filter 27 is provided at one end of an intake pipe, an end of the intake pipe is connected to the venturi 21, and an air flow meter 28 is provided in the middle of the intake pipe. The engine 10 is provided with an intake valve 10a, a spark plug 10b, and the like, and a temperature sensor 29 for measuring the temperature of the cooling water.
[0016]
The electronic control system includes a control device (ECM: Electronic Control Module) 30, and the control device 30 includes a fuel injection control unit. The fuel injection control means controls the driving of the injectors 18 and 22 based on an intake air amount detected by the air flow meter 28 and an engine rotation signal detected by a crank angle sensor (not shown), and a throttle opening sensor 33. The valve opening of the electronically-controlled throttle 23 is controlled based on the throttle opening signal detected by the accelerator pedal, the accelerator opening signal detected by the accelerator opening sensor 31a of the accelerator pedal 31, and the like. The vehicle speed sensor 32 is provided at a position for detecting the rotation of the drive shaft for driving the drive wheels 11, and a rotation signal due to the rotation of the drive shaft is input to the control device 30 to detect the vehicle speed. ing.
[0017]
Further, the control device 30 is provided with the above-described fuel injection control means and each control means such as a maximum speed control means 30a, a vehicle speed detection means 30b, a cargo handling determination means 30c, and a switching control means 30d. . The maximum speed control means 30a is a control function for controlling the maximum speed so as not to exceed a predetermined speed, for example, when traveling on a premises or when the lightness of the cargo handling work place is low, and even if the driver operates the accelerator pedal 31. Control is performed so as not to exceed a predetermined vehicle speed.
[0018]
In the vehicle speed detection means 30b, a rotation signal from the vehicle speed sensor 32 is input to the control device 30, and the rotation signal is counted to calculate the vehicle speed. When detecting that the vehicle speed, which is the output based on the vehicle speed detecting means 30b, is zero, the cargo handling determining means 30c automatically determines that the cargo handling work is being performed and outputs a cargo handling detection signal. The cargo detection signal is output when the cargo handling vehicle is stopped. The cargo handling detection signal is input to the switching control means 30d, and based on the switching signal from the switching control means 30d, the control function of the maximum speed control means 30a is released, the rotation speed of the engine 10 is increased, and the engine 10 Is controlled to maximize the shaft torque of
[0019]
That is, the control for restricting the throttle opening of the electronically controlled throttle 23 by the maximum speed control means 30a is released, and the driver operates the accelerator pedal 31 to control the throttle opening to the maximum. Thus, control can be performed such that the amount of air to the engine 10 is maximized to increase the engine speed and the shaft torque of the engine 10 is maximized. Further, when the cargo handling work is completed by operating the cargo handling lever 14, switching control is performed based on the switching control means 30d so as to restore the function of the maximum speed control means 30a.
[0020]
In the present embodiment, when the vehicle speed of the cargo handling vehicle is zero, the logic is configured so that the cargo handling determination means 30c determines that the cargo handling work is being performed, and the control function of the maximum speed control means 30a is released to release the accelerator pedal. The throttle opening of the electronically controlled throttle 23 is controlled to be maximum so that the shaft torque of the engine 10 is maximized in accordance with the operation of the engine 31, so that the shaft torque of the engine is controlled to maximum, so that there is no hindrance to the cargo handling work Can be controlled as follows. Alternatively, when the vehicle speed of the cargo handling vehicle is zero and the cargo handling lever 13 is operated, it is determined that the cargo handling work is being performed, and the control function of the maximum speed control means 30a may be released.
[0021]
Further, the maximum speed control means in the present embodiment includes a control means for regulating the maximum speed in accordance with the lightness of the cargo handling work place or traveling, and this regulation is released under a certain condition that the cargo handling work is started. As a result, the shaft torque of the engine can be controlled to the maximum.
[0022]
【The invention's effect】
As described above, according to the present invention, even when the maximum speed is regulated, during the loading and unloading operation, the throttle opening of the electronically controlled throttle is maximized so that the shaft torque of the engine is maximized. It is controlled so that it can be controlled, and there is an advantage that the output shortage of the engine during the cargo handling operation can be eliminated.
[0023]
Further, according to the present invention, there is an advantage that the cargo handling work is automatically determined and the cargo handling work is facilitated without manually releasing the regulation of the maximum speed.
[Brief description of the drawings]
FIG. 1 is a schematic system diagram showing an embodiment of an engine output control device for a cargo handling vehicle according to the present invention.
FIG. 2 (a) is a schematic side view of a conventional cargo handling vehicle, and FIG. 2 (b) is a diagram for explaining a limitation of a maximum speed according to a loading / unloading work place and brightness during traveling.
[Explanation of symbols]
Reference Signs List 10 engine 11 drive wheel 12 hydraulic pump 13 cargo handling lever 14 mast 15 lift 16 intake pipe 17 gas tank 18 injector 19 gas cylinder 20 vaporizer 21 venturi 22 fuel injector 23 electronic control throttle 24 oxygen sensor 25 catalyst 26 manifold filter 27 air filter 28 air flow Meter 29 Temperature sensor 30 Control device 30a Maximum speed control means 30b Vehicle speed detection means 30c Cargo handling determination means 30d Switching control means 31 Accelerator pedal 31a Accelerator opening sensor 32 Vehicle speed sensor 33 Throttle opening sensor

Claims (3)

Electronic control of the maximum speed of the cargo handling vehicle In an engine output control device for a cargo handling vehicle that regulates the throttle opening of the throttle to suppress the maximum speed,
Vehicle speed detecting means for detecting the speed of the cargo handling vehicle;
Loading / unloading determining means for detecting that the vehicle speed is zero from the output of the vehicle speed detecting means and determining that it is a cargo handling operation,
An engine output control device for a cargo vehicle, wherein when the cargo handling determination means detects a cargo handling operation, the restriction on the throttle opening of the electronically controlled throttle is released to maximize the shaft torque of the engine. Electronic control of the maximum speed of the cargo handling vehicle In an engine output control device for a cargo handling vehicle that regulates the throttle opening of the throttle to suppress the maximum speed,
Maximum speed control means for controlling so as to suppress the maximum vehicle speed of the cargo handling vehicle,
Vehicle speed detecting means for detecting the speed of the cargo handling vehicle;
Cargo handling determining means for detecting that the output of the vehicle speed detecting means is zero and determining that the cargo handling work is performed;
Switching control means for releasing the restriction on the maximum vehicle speed by the maximum speed control means and releasing the restriction on the throttle opening of the electronically-controlled throttle when the loading determination means detects the loading operation. Output control device for cargo handling vehicles. A cargo handling vehicle comprising the engine output control device for a cargo handling vehicle according to claim 1 or 2.

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