JP4124971B2 - Industrial vehicle taillight braking light control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device for a taillight braking light of an engine-type industrial vehicle that employs a hydraulic drive system.
[0002]
[Prior art]
Conventionally, as a power transmission device of a general engine type forklift (an example of an industrial vehicle), a clutch type or a torque converter type has been mainstream, but there is also an engine type forklift that employs a hydraulic drive system. Engine-type forklifts that employ this hydraulic drive system have 1 pump, 1 motor type, 1 pump, 2 motor type, and 2 pump, 2 motor type. In these types, the motor (hydraulic motor) is connected to the front wheel of the wheel, and the pump By controlling the amount of hydraulic oil discharged from the (hydraulic pump) to the hydraulic motor, the speed of the hydraulic motor is controlled to control the speed of the vehicle. The amount of hydraulic oil discharged to the hydraulic motor is determined by controlling (setting) the swash plate angle of the hydraulic pump. Features of this hydraulic drive system include high efficiency and no need for a front differential.
[0003]
The brake (operation structure) of this hydraulic drive system has a structure in which the hydraulic brake is applied and braked by setting the swash plate angle of the hydraulic pump to 0 degrees.
Furthermore, engine-type forklifts that employ a hydraulic drive system enable automotive control that uses an electric controller hydraulic pump to freely control the vehicle speed by the amount of accelerator depression, for work efficiency and energy-saving travel.
[0004]
The taillight braking light of the vehicle is turned on by depressing a switch attached to the brake pedal bracket with the brake pedal.
[0005]
[Problems to be solved by the invention]
However, in the engine-type industrial vehicle employing the above-described conventional hydraulic drive system, when the operator of the vehicle removes his / her foot from the accelerator pedal and the accelerator depression amount becomes zero, the taillight braking light of the vehicle does not light up, Since the swash plate angle of the hydraulic pump is controlled to 0 degree and the hydraulic brake is applied and the vehicle decelerates suddenly, the vehicle operator does not step on the brake pedal, and the vehicle suddenly decelerates without turning on the vehicle taillight brake light. There was a case. For this reason, the operator of the following vehicle is greatly different from the deceleration feeling of the vehicle adopting the clutch type or the torque converter type, and there is a possibility that danger such as rear-end collision may occur. Further, in order to avoid this danger, there has been a problem that the working efficiency of the operator of the following vehicle is lowered.
[0006]
Therefore, the present invention provides an industrial vehicle taillight braking light control device that can reliably turn on a taillight braking light during deceleration in an industrial vehicle that employs a hydraulic drive system and informs subsequent vehicles of deceleration. It is intended.
[0007]
[Means for Solving the Problems]
In order to achieve the above-described object, the invention according to claim 1 of the present invention is such that the left and right wheels are connected to the drive shafts on the left and right hydraulic motors respectively attached to the vehicle body, and the vehicle body is driven by the engine. Industrial vehicles in which a pair of hydraulic pumps are provided, the hydraulic motors are connected to the left and right hydraulic pumps, respectively , and the rotational speed of each hydraulic motor is controlled by controlling the angle of the swash plate of each hydraulic pump A control device for taillight braking lights in
Each hydraulic motor is provided with a speed sensor that detects the number of rotations of the hydraulic motor, and the amount of operation of the accelerator pedal of the vehicle or the lever corresponding to this accelerator pedal, or the engine rotation that changes by operating the accelerator pedal or lever An accelerator pedal operation amount detecting means for detecting the number and an average value of the rotational speeds of the respective hydraulic motors detected by the respective speed sensors are calculated to obtain a motor rotational speed corresponding to the actual traveling speed of the vehicle. A control means is provided for differentiating the motor rotational speed to obtain the actual vehicle deceleration,
The control means estimates the motor rotation speed and the vehicle deceleration corresponding to the traveling speed of the vehicle according to the operation amount of the accelerator pedal or lever or the engine rotation speed detected by the accelerator pedal operation amount detection means, When the obtained actual vehicle deceleration is equal to or greater than the estimated deceleration, and when the rotational speed of the hydraulic motor detected by each speed sensor is within the estimated motor rotational speed, the taillight braking of the vehicle is performed. The lamp is turned on .
[0008]
According to the above configuration, when the accelerator pedal or the lever is operated , the motor rotation number corresponding to the vehicle traveling speed and the vehicle deceleration are estimated according to the operation amount, and the obtained actual vehicle deceleration is calculated. When the estimated deceleration is exceeded or more and the rotational speed of the hydraulic motor detected by each speed sensor is within the estimated motor rotational speed, the taillight braking lamp of the vehicle is turned on. Therefore, when the operator of the vehicle releases the accelerator pedal or lever (when the accelerator operation amount is operated to zero), the angle of the swash plate of the hydraulic pump is controlled to 0 degrees, and the hydraulic brake is activated and suddenly decelerates. Regardless of whether the brake pedal is operated or not, the taillight braking light of the vehicle is turned on, the deceleration of the following vehicle is notified to the operator , and the vehicle has a speed difference between the left and right wheels due to a pivot turn etc. When this is considered, the taillight braking light of the vehicle is not lit, as distinguished from deceleration by a hydraulic brake.
[0011]
The invention according to claim 2 is the invention according to claim 1 , further comprising operation detecting means for detecting an operation of a brake pedal or a lever corresponding to the brake pedal, wherein the control means When the operation of the brake pedal or lever is detected by the detecting means, the taillight braking light of the vehicle is turned on.
[0012]
According to the above configuration, when the brake pedal or the lever is operated, the taillight braking lamp of the vehicle is turned on, and the deceleration of the following vehicle is notified to the operator.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 3, a forklift (an example of an industrial vehicle) 1 is provided with a pair of left and right front wheels (drive wheels) 3A, 3B at the front of a vehicle body 2 and a pair of left and right rear wheels 4A at the rear. 4B, and a driver's seat 5 is provided above the front portion of the vehicle body 2. A mast 6 that can be expanded and contracted in the vertical direction is attached to the front end portion of the vehicle body 2 via a connecting shaft 7 in the vehicle width direction so as to be rotatable in the front-rear direction, and a tilt cylinder 8 that rotates in the front-rear direction. It is provided between the vehicle body 2 and the mast 6.
[0014]
The mast 6 includes a pair of left and right outer frames 9 on the forklift 1 side, and a pair of left and right inner frames 10 which are guided by the outer frame 9 and can be moved up and down, and between the outer frame 9 and the inner frame 10. A lift cylinder 11 is provided. Further, a lift bracket 12 that is guided to the inner frame 10 side and that can freely move up and down is provided, and a pair of left and right forks 13 is provided on the lift bracket 12 via a pair of upper and lower finger bars.
[0015]
The driver's seat 5 is provided with a seat 15 and a handle 16 positioned in front of the seat 15, and above the head via a front pipe 17 and a rear pipe 18 standing from the main body 2 side. A guard 19 is provided. Further, a counterweight 20 is provided on the main body 2 behind the seat 15.
[0016]
The rim 3a of the pair of left and right front wheels 3A and 3B is directly attached to the rotating flanges (drive shafts) 22A and 22B of the hydraulic motors 21A and 21B via the coupling tools 23A and 23B, respectively. Linked to the 21B side. The mounts of the hydraulic motors 21A and 21B are fixed to the vehicle body 2 side, that is, the front frame.
[0017]
Further, a taillight braking lamp 24 is provided at a position below the counterweight 20 at the rear (rear surface) of the main body 2.
Further, an engine 25 is provided on the vehicle body 2 side, and a main pump that supplies hydraulic oil to a pair (a plurality) of hydraulic pumps (HST tandem pumps) 26A and 26B and a cargo handling device such as the lift cylinder 11 or the like. 14 is directly attached. At that time, the mounting method is rubber mounting with the engine 25 and the frame. Then, the corresponding hydraulic pumps 26A, 21B are arranged so that one hydraulic pump 26A, 26B corresponds to one hydraulic motor 21A, 21B, that is, a two-pump two-motor type hydraulic drive system (HST system). 26B and hydraulic motors 21A and 21B are connected via pipes (hydraulic hoses and the like) 27A and 27B.
[0018]
The pair of left and right rear wheels 4A and 4B are provided so as to be turnable around the longitudinal axes 29A and 29B with respect to the vehicle body 2, respectively. In addition, 30 is an electric change lever, 31 is a controller (an example of control means), 32 is an electric accelerator pedal, and 33 is attached to the center of rotation of the accelerator pedal 32 to detect the amount of depression of the accelerator pedal 32. Rotation sensor (an example of an accelerator pedal operation amount detection means; hereinafter referred to as an accelerator sensor), 34 is a brake pedal, 35 is operated by depressing the brake pedal 34, and a switch (operation detection means of the operation detection means) is operated. An example). Although a rotation sensor is used as the accelerator sensor 33, a stroke sensor or the like may be employed instead of the rotation sensor.
[0019]
The hydraulic pumps 26A and 26B are configured as an electric control type in which the angle of the swash plate is controlled by a command signal from the controller 31. By setting the amount of hydraulic oil discharged to the hydraulic motors 21A and 21B by the angle of the swash plate, the speed of the hydraulic motors 21A and 21B is controlled by rotating the swash plate, and the speed of the vehicle is increased. Be controlled. When the swash plate is neutral (the angle is 0 °), the amount of hydraulic oil discharged is 0, and the vehicle stops (that is, the brake is effective). Further, the direction of the hydraulic oil discharged from the hydraulic pumps 26A and 26B to the hydraulic motors 21A and 21B is reversed in accordance with the forward-reverse position of the electric change lever 30. Each of the hydraulic motors 21A and 21B is provided with rotation sensors (an example of travel speed detecting means) 36A and 36B for detecting the rotation speed (the rotation speed of the front wheels 3A and 3B). Hereinafter, the rotation sensors 36A and 36B are referred to as speed sensors.
[0020]
As shown in FIG. 3, the controller 31 includes a forward-neutral-reverse position signal of the change lever 30, a voltage signal (v) corresponding to the depression angle of the accelerator pedal 32 detected by the accelerator sensor 33, and a switch 35. The brake pedal 34 depressing signal (ON / OFF signal) detected by, and the rotation speed (rpm) signals of the front wheels 3A and 3B (hydraulic motors 21A and 21B) detected by the speed sensors 36A and 36B, respectively, are input. A swash plate angle command signal corresponding to a travel command is output from the controller 31 to the hydraulic pumps 26A and 26B, and an on-off signal (lighting-off signal) is output to the taillight braking lamp 24. The angle of the swash plate is set by the depression angle of the accelerator pedal 32, and the direction of hydraulic oil discharged from the hydraulic pumps 26A, 26B to the hydraulic motors 21A, 21B is set by a position signal of the change lever 30.
[0021]
The on / off control of the taillight braking lamp 24 in the controller 31 will be described with reference to the block diagram of FIG.
In FIG. 4, reference numeral 41 denotes an average value of the rotational speeds (rpm) nA and nB of the front wheels 3A and 3B detected by the speed sensors 36A and 36B, respectively, and the motor rotational speed corresponding to the actual vehicle traveling speed ( (rpm) is an average value calculator 42, and 42 is a differentiator for differentiating the motor rotational speed (rpm) obtained by the average value calculator 41 to obtain the vehicle acceleration / deceleration (m / s ² ). The speed sensors 36A and 36B, the average value calculator 41, and the differentiator 42 constitute a deceleration detection means.
[0022]
Reference numeral 43 denotes a voltage corresponding to the depression angle of the accelerator pedal 32 and the forward-neutral-reverse position of the change lever 30, and the above-mentioned voltage during forward and reverse as shown in FIG. ) Is a first function part 44 for converting the voltage corresponding to the depression angle of the accelerator pedal 32 to a vehicle set deceleration (m / s ² ) as shown in FIG. . In the first function section 43, a curve of the motor speed (rpm) estimated by the depression angle (voltage) of the accelerator pedal 32 is set, and in the second function section 44, the depression of the accelerator pedal 32 is set. A curve of the deceleration (m / s ² ) estimated (set) by the angle (voltage) is set.
[0023]
The set motor rotational speed (rpm) x, which is the output of the first function unit 43, is determined by the rotational speeds (rpm) nA and nB of the front wheels 3A and 3B detected by the speed sensors 36A and 36B, respectively. It is compared, and it is determined whether the motor rotational speeds (rpm) nA and nB are both within the set motor rotational speed (rpm) x during forward traveling and reverse traveling. The set deceleration (m / s ² ) α, which is the output of the second function unit 44, is compared with the vehicle acceleration / deceleration (m / s ² ) d obtained by the differentiator 42 in the second determination unit 46, It is determined whether the vehicle deceleration (m / s ² ) d is equal to or greater than the set deceleration (m / s ² ) α.
[0024]
Reference numeral 47 denotes a logical product circuit (AND circuit) that obtains a logical product of the judgment signal of the first judgment unit 45 and the judgment signal of the second judgment unit 46, and is detected by the AND output signal of the logical product circuit 47 and the switch 35. A logical sum circuit (OR circuit) 48 for obtaining a logical sum and a depression signal of the brake pedal 34 to be output and outputting it to the tail lamp braking lamp 24 is provided.
[0025]
By the on / off control block of the taillight braking lamp 24, an on signal is output to the taillight braking lamp 24 in the following two ways, and the taillight braking lamp 24 is turned on.
1. The actual deceleration of the vehicle is greater than the amount of depression of the accelerator pedal 32 (including the case where deceleration occurs when the amount of depression of the accelerator pedal is zero) and the amount of depression of the accelerator pedal 32 When the actual motor rotation speed (rpm) of the left and right front wheels 3A, 3B follows normally,
That is, as shown in FIG. 6, in the second function unit 44, a (set) deceleration (m / s ² ) α estimated by the depression angle (voltage) of the accelerator pedal 32 is obtained, and this set deceleration (m / S ² ) α and the actual vehicle deceleration (m / s ² ) d are compared by the second determination unit 46, and the actual deceleration (m / s ² ) d is set to the set deceleration (m / s ^2). ) When α is equal to or greater than (in the range indicated by hatching in FIG. 6), and (AND), as shown in FIG. 5, the first function unit 43 estimates the depression angle (voltage) of the accelerator pedal 32. (Setting) The motor rotational speed (rpm) x is obtained, the set motor rotational speed (rpm) x and the actual motor rotational speed (rpm) nA, nB are compared by the first determination unit 45, and these actual motor rotational speeds are compared. If the number (rpm) nA and nB are both within the set motor speed (rpm) x {When the actual motor speed (rpm) nA, nB follows the amount of depression of the accelerator pedal 32 within the range indicated by the hatched lines in FIG. 5}, an ON signal is output to the taillight braking lamp 24. .
[0026]
By ignoring a range other than the range indicated by the hatched lines in FIG. 6, it is possible to cope with the operation of the accelerator pedal 32, the climbing traveling, and the traveling from a good road to a bad road. In addition, when a range other than the range shown by hatching in FIG. 5 is ignored, the vehicle 1 turns due to a pivot turn or the like, and a difference is generated in the rotational speeds of the left and right wheels 3A and 3B. The taillight braking light 24 is not turned on.
2. When the depression of the brake pedal 34 is detected by the switch 35, an ON signal is output to the tail lamp braking lamp 24.
[0027]
In this way, when the brake pedal 34 is depressed, the actual motor rotation speed (rpm) when the vehicle is decelerated by the hydraulic brake of the hydraulic drive system and with respect to the depression amount of the accelerator pedal 32. When nA and nB follow, the taillight braking lamp 24 is turned on, and the subsequent vehicle is notified of deceleration. Therefore, the operator of the following vehicle can detect the danger such as a rear-end collision with the same feeling as the deceleration feeling of the vehicle adopting the clutch type or the torque converter type, can avoid the danger, and the safety of the following vehicle Can be improved. In addition, it is possible to improve the working efficiency of the operator of the following vehicle.
[0028]
In this embodiment, the angle signal of the accelerator pedal 32 is obtained, but instead of the angle signal of the accelerator pedal 32, the number of revolutions of the engine 25 that changes when the accelerator pedal 32 is depressed is obtained, and the accelerator pedal operation is determined. The amount may be obtained.
[0029]
In this embodiment, the accelerator pedal 32 is used for the accelerator operation. However, a lever corresponding to the accelerator pedal may be used, and the brake pedal 34 is used, but it corresponds to the brake pedal. You may make it use the lever to do.
[0030]
【The invention's effect】
As described above, according to the present invention, in an industrial vehicle adopting a hydraulic drive system, the taillight braking lamp can be reliably turned on at the time of deceleration, and the subsequent vehicle can be notified of the deceleration. Therefore, the safety of the following vehicle can be improved, and the working efficiency of the operator of the following vehicle can be improved.
[Brief description of the drawings]
FIG. 1 is a side view of a hydraulically driven forklift according to an embodiment of the present invention.
FIG. 2 is a partially cutaway plan view of a wheel portion of the hydraulically driven forklift.
FIG. 3 is a system configuration diagram of the hydraulically driven forklift.
FIG. 4 is a control block diagram of a controller of the hydraulic drive forklift.
FIG. 5 is a function diagram of a controller of the hydraulic drive forklift.
FIG. 6 is a function diagram of a controller of the hydraulic drive forklift.
[Explanation of symbols]
1 Forklift 2 Car body 3A, 3B Front wheel
21A, 21B Hydraulic motor
24 Taillight brake light
25 engine
26A, 26B Hydraulic pump
30 Change lever
31 Controller (control means)
32 Accelerator pedal
33 Rotation sensor (detection means)
34 Brake pedal
35 switch (detection means)
36A, 36B Rotation sensor (detection means)

Claims (2)

The left and right wheels are connected to the drive shafts of the left and right hydraulic motors attached to the vehicle body, respectively, and a pair of hydraulic pumps driven by the engine are provided on the vehicle body side, and the hydraulic motors are connected to the left and right hydraulic pumps, respectively. The rotational speed of each hydraulic motor is a control device for a taillight braking light in an industrial vehicle controlled by controlling the angle of the swash plate of each hydraulic pump,
Each hydraulic motor is provided with a speed sensor that detects the rotational speed of the hydraulic motor,
An accelerator pedal operation amount detection means for detecting an operation amount of an accelerator pedal of a vehicle or a lever corresponding to the accelerator pedal, or an engine speed that changes by operating the accelerator pedal or the lever;
An average value of the rotational speeds of the respective hydraulic motors detected by the speed sensors is calculated, a motor rotational speed corresponding to the actual traveling speed of the vehicle is obtained, and the actual rotational speed of the vehicle is reduced by differentiating the motor rotational speed. Control means for determining speed
Provided,
The control means estimates the motor rotation speed and the vehicle deceleration corresponding to the traveling speed of the vehicle according to the operation amount of the accelerator pedal or lever or the engine rotation speed detected by the accelerator pedal operation amount detection means, When the obtained actual vehicle deceleration is equal to or greater than the estimated deceleration, and when the rotational speed of the hydraulic motor detected by each speed sensor is within the estimated motor rotational speed, the taillight braking of the vehicle is performed. A taillight braking light control device for an industrial vehicle, characterized by lighting a lamp. Comprising an operation detecting means for detecting an operation of a brake pedal or a lever corresponding to the brake pedal;
The tail light braking of an industrial vehicle according to claim 1, wherein the control means turns on a tail light braking light of the vehicle when the operation detecting means detects an operation of a brake pedal or a lever. Light control device.

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