JP3686571B2 - Tractor constant speed travel device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the running stability of a tractor which is not towing a trailer, while the friction resistance of a road surface is small, as when it rains. SOLUTION: A coupler switch 22 for detecting the towed condition of a trailer is connected in series with the signal line of an automatic cruise main switch (hereinafter referred to as main switch) for selecting travel at constant speed. A determination is made as to whether or not requirements for the travel at constant speed are met, according to switches and sensors 26 to 36 for detecting various running conditions of the tractor 10; if the requirements are met and a signal from the main switch 24 is on, that is, both the main switch 24 and the coupler switch 22 are turned on, the travel at constant speed is carried out. In this way, the signal from the main switch 24 is turned off when the trailer is not towed, so that when road surface resistance is small, the travel at constant speed is prevented to prevent idling of drive wheels with light axle load.

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a constant speed traveling device for a tractor that pulls a trailer, and more particularly to a technique for improving traveling safety when a trailer is not pulled.
[0002]
[Prior art]
Conventionally, in order to reduce the labor of the driver when traveling on a highway or the like, the engine or the like has been controlled so as to maintain a set constant speed regardless of increase or decrease in driving resistance. A high speed travel device is known. Such a constant speed traveling device may be mounted on a tractor that pulls a trailer.
[0003]
[Problems to be solved by the invention]
However, in the prior art, the constant speed traveling device is operated regardless of whether the trailer is towed or not pulled.
[0004]
That is, in the tractor, generally, when pulling a trailer loaded with a load, the torque in the drive wheels is set for the purpose of ensuring necessary and sufficient acceleration performance. For this reason, when the trailer is not towed, the axle load of the drive wheel of the tractor becomes lighter, and when the road surface friction resistance is low, such as in rainy weather, the torque acting on the drive wheel is too large and the drive wheel is idling. There was a risk. When the driving wheel slips, the straightness of the vehicle decreases, and the driver has to perform delicate steering wheel operations.
[0005]
Therefore, in view of the conventional problems as described above, the present invention is such that when the tractor is not towing the trailer, the road surface friction resistance is low, such as in rainy weather, by preventing the shift to the constant speed traveling. An object of the present invention is to provide a tractor constant-speed traveling device with improved traveling safety.
[0006]
[Means for Solving the Problems]
Therefore, according to the first aspect of the present invention, the constant speed traveling condition determining means for determining whether or not the constant speed traveling condition is satisfied, the traction state detecting means for detecting the traction state of the trailer, and the constant speed traveling condition Only when it is determined that the constant speed running condition is established by the judging means and the trailer towing state is detected by the towing state detecting means, the constant speed running is performed so as to maintain the set constant vehicle speed. A constant speed traveling device for the tractor including the traveling means.
[0007]
According to such a configuration, in order for the tractor to shift to the constant speed traveling, the constant speed traveling condition must be satisfied, and the trailer pulling state must be detected. For this reason, when the tractor is not towing the trailer, it does not shift to constant speed driving even if the constant speed driving condition is satisfied, and even if the road resistance is low, such as in rainy weather The wheel is prevented from idling.
[0008]
The invention according to claim 2 is characterized in that the traction state detecting means is a coupler switch attached to a coupler for connecting a trailer.
According to such a configuration, the trailer pulling state is detected using existing components. That is, in the tractor that pulls the trailer, braking control is performed in which braking is performed before the trailer from the viewpoint of preventing a jackknife phenomenon during braking. For this reason, in order to detect whether the trailer is being pulled or not, a coupler switch is usually attached to the coupler. Therefore, if the signal from the coupler switch is used, it is detected whether or not the trailer is being pulled without adding a new switch or other components.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 shows a first embodiment of a tractor constant speed traveling apparatus (hereinafter referred to as “constant speed traveling apparatus”) according to the present invention.
[0010]
The engine control unit 20 mounted on the tractor 10 is provided with a function as a constant speed traveling means for increasing or decreasing the amount of fuel supplied to the engine in accordance with the traveling resistance, for example, so as to travel at a set constant speed. . Here, since the technique for constructing the constant speed traveling means is a known technique, description of the specific contents thereof is omitted. The engine control unit 20 realizes a constant speed traveling condition determination means by software.
[0011]
A coupler 14 for pulling a trailer (not shown) is attached to the upper surface of the platform 12 located at the rear of the tractor 10. As shown in FIG. 2, the coupler 14 supports the trailer by a coupler base (saddle) 14a that forms the upper surface thereof, and is coupled to the king pin of the trailer by a jaw mechanism (not shown) mounted at the center lower part of the coupler base 14a. And has a function of transmitting traction force, braking force, and the like to the trailer. Coupler switch 22 is attached to coupler 14 as traction state detecting means for detecting whether or not the trailer is being pulled. The coupler switch 22 is already installed in a general trailer, for example, in order to input a signal necessary for braking control for braking first from a trailer to be pulled so that a jackknife phenomenon does not occur during braking. Of course.
[0012]
The engine control unit 20 includes an auto cruise main switch (hereinafter referred to as “main switch”) 24, a set switch 26, a brake pedal switch 28, a clutch pedal switch 30, a shift position sensor 32, an auxiliary brake operation relay 34, and a vehicle speed sensor 36. Are input respectively. Here, the switches and the like will be briefly described. The main switch 24 is a switch for selecting whether or not to perform constant speed running, and is ON when performing constant speed running, and when not performing constant speed running. This switch is turned off. The set switch 26 is a switch for setting a constant vehicle speed for constant speed running, and is a switch that is turned on only when it is pressed. The brake pedal switch 28 is a switch that detects the operating state of the service brake through the operation state of the pedal, and is a switch that is turned on only when the service brake is operated by depressing the pedal. The clutch pedal switch 30 is a switch that detects the clutch engagement / disengagement state via the pedal operation state, and is a switch that is turned on only when the pedal is depressed and the clutch is disengaged. The shift position sensor 32 is a switch that detects a shift state of the transmission at the present time, and is a switch that detects at least whether the transmission is in the neutral or traveling stage. The auxiliary brake operation relay 34 detects whether an auxiliary brake such as an exhaust brake or a retarder is operating, and is a relay that is turned on while the exhaust brake is operating. The vehicle speed sensor 36 is a sensor that detects the current vehicle speed.
[0013]
Here, the coupler switch 22 is connected in series to the signal line of the main switch 24 as shown in the figure. Therefore, even if the main switch 24 is ON, the coupler switch 22 is OFF if the trailer is not pulled, and the signal from the main switch 24 input to the engine control unit 20 is OFF. That is, unless both the main switch 24 and the coupler switch 22 are turned on, the engine control unit 20 determines that the main switch 24 is turned off.
[0014]
Further, an auto cruise lamp 38 is attached to the dashboard (not shown) of the tractor 10 to notify the driver that the vehicle is ready for constant speed running. The auto cruise lamp 38 is turned on or off by the engine control unit 20.
[0015]
FIG. 3 is a flowchart showing the control contents of the constant speed traveling apparatus in the first embodiment.
In step 1 (abbreviated as “S1” in the figure, the same applies hereinafter), it is determined whether or not the main switch 24 is ON, that is, whether or not constant speed running is selected. If the main switch 24 is ON, the process proceeds to Step 2 (Yes), and if the main switch 24 is OFF, the process proceeds to Step 8 (No). Here, since the signal from the main switch 24 is not turned on unless the coupler switch 22 is turned on as described above, it is indirectly determined whether the trailer is pulled through the signal of the main switch 24. Is determined.
[0016]
In step 2, it is determined by the self-diagnosis function provided in the engine control unit 20 whether or not the system of the constant speed traveling device is normal. If the system is normal, the process proceeds to step 3 (Yes), and if the system is abnormal, the process proceeds to step 8 (No).
[0017]
In step 3, the auto-cruise lamp 38 is turned on to notify the driver that the vehicle is ready for constant speed travel.
In step 4, it is determined whether or not the set switch 26 is turned on. If the set switch 26 is ON, the process proceeds to step 5 (Yes), and if the set switch 26 is OFF, the process returns to step 1 (No).
[0018]
In step 5, whether or not the constant speed running condition is satisfied based on signals from the main switch 24, the brake pedal switch 28, the clutch pedal switch 30, the shift position sensor 32, the auxiliary brake operation relay 34, and the vehicle speed sensor 36. Is determined. That is, when the main switch 24 is ON, the service brake is not operated, the clutch is engaged, the shift position is the travel stage, the auxiliary brake is not operated, and all the conditions within the predetermined range of the vehicle speed are satisfied, the constant speed travel condition is It is determined that it has been established. If the constant speed traveling condition is satisfied, the process proceeds to Step 6 (Yes), and if the constant speed traveling condition is not satisfied, the process proceeds to Step 7 (No). Here, as a requirement for satisfying the constant speed running condition, the signal from the main switch 24 is monitored because the main switch 24 is OFF, that is, the driver reflects the intention to stop the constant speed running. It is. In addition, the process of step 5 corresponds to a constant speed traveling condition determination means.
[0019]
In step 6, the vehicle speed when the set switch 26 is pressed is set as a constant speed for constant speed travel, and constant speed travel is performed based on the vehicle speed. Then, the process returns to step 5.
[0020]
In step 7, the constant speed running is canceled. That is, when the set switch 26 is pressed, if the constant speed running condition is not satisfied, the transition to the constant speed running is not performed. On the other hand, during constant speed traveling, for example, when braking is performed by operating a service brake, the constant speed traveling is canceled. Then, the process returns to step 1.
[0021]
In step 8, processing when the main switch 24 is OFF or the system is abnormal is performed. That is, when the driver does not want to drive at a constant speed (including when the trailer is not towed), when the system is abnormal, the auto is used to inform the driver that the vehicle is not ready for constant speed driving. The cruise lamp 38 is turned off. Then, the process proceeds to step 7 where the constant speed traveling is canceled.
[0022]
According to the processing of Step 1 to Step 8, in order to complete the preparation for constant speed running, the main switch 24 must be ON and the system should be normal. In this case, since the coupler switch 22 is turned off when the tractor 10 is not towing the trailer, the engine control unit 20 determines that the main switch 24 is turned off even if the main switch 24 is turned on. Therefore, when the trailer is not towed, it is not possible to prepare for constant speed running, and in the state where the road surface friction resistance is low, such as in rainy weather, the idling of the driving wheel due to the light axle load is prevented. can do. And the driving | running | working safety | security when not pulling the trailer can be improved.
[0023]
Further, during the constant speed traveling, the constant speed traveling condition is established based on signals from the main switch 24, the brake pedal switch 28, the clutch pedal switch 30, the shift position sensor 32, the auxiliary brake operation relay 34, and the vehicle speed sensor 36. When it is determined that the vehicle has stopped, the constant speed traveling is canceled. This is the same as the control in a general constant speed traveling device.
[0024]
FIG. 4 shows a second embodiment of the constant speed traveling device according to the present invention.
In the second embodiment, the coupler switch 22 is not connected in series to the signal line of the main switch 24, and the signal is directly input to the engine control unit 20. Since other configurations are the same as those in the first embodiment, the description thereof will be omitted.
[0025]
FIG. 5 shows a third embodiment of the constant speed traveling device according to the present invention.
In the third embodiment, the signal of the coupler switch 22 is input to a control unit 40 of another system, for example, a control unit that performs braking control of the tractor 10 and the trailer. Various control signals are exchanged between the engine control unit 20 and the control unit 40 of another system via CAN (Controller Area Network) communication. At this time, at least a signal indicating whether or not the trailer is being pulled is transmitted to the engine control unit 20 from the control unit 40 of the other system. Regarding the braking control, the reason why the towing state of the trailer must be detected is as described. Since other configurations are the same as those in the first embodiment, as in the second embodiment, the description thereof will be omitted.
[0026]
FIG. 6 is a flowchart showing the control contents of the constant speed traveling device in the second and third embodiments. Note that the description of the steps in which the same processing as in the first embodiment is performed will be simplified.
[0027]
In step 11, it is determined whether or not the main switch 24 is ON. If the main switch 24 is ON, the process proceeds to step 12 (Yes), and if the main switch 24 is OFF, step 19 is performed. Go to (No). Here, in the second and third embodiments, as apparent from FIGS. 4 and 5, the signal of the main switch 24 input to the engine control unit 20 does not include the signal of the coupler switch 22. .
[0028]
In step 12, it is determined whether or not the system of the constant speed traveling apparatus is normal. If the system is normal, the process proceeds to step 13 (Yes), and if the system is abnormal, the process proceeds to step 19 (No). .
[0029]
In step 13, it is determined whether or not the trailer is being pulled. That is, in the second embodiment shown in FIG. 4, it is determined whether or not the coupler switch 22 is ON. If the coupler switch 22 is ON, the process proceeds to step 14 (Yes), and the coupler switch 22 is OFF. If so, the process proceeds to step 19 (No). On the other hand, in the third embodiment shown in FIG. 5, it is determined whether the trailer is towed based on a signal transmitted from the control unit 40 of another system via CAN communication, and the trailer is towed. If so, the process proceeds to step 14 (Yes), and if the trailer is not pulled, the process proceeds to step 19 (No).
[0030]
In step 14, the auto cruise lamp 38 is turned on.
In step 15, it is determined whether or not the set switch 26 is ON. If the set switch 26 is ON, the process proceeds to step 16 (Yes), and if the set switch 26 is OFF, step 11 is performed. Return to (No).
[0031]
In step 16, constant speed running conditions are established based on the signals from the main switch 24, coupler switch 22, brake pedal switch 28, clutch pedal switch 30, shift position sensor 32, auxiliary brake operation relay 34, and vehicle speed sensor 36. It is determined whether or not. If the constant speed traveling condition is satisfied, the process proceeds to step 17 (Yes), and if the constant speed traveling condition is not satisfied, the process proceeds to step 18 (No). In addition, the process of step 16 corresponds to a constant speed traveling condition determination means.
[0032]
In step 17, the vehicle speed when the set switch 26 is pressed is set as a constant speed for constant speed travel, and constant speed travel is performed based on the vehicle speed. Then, the process returns to step 16.
[0033]
In step 18, the constant speed running is canceled.
In step 19, processing is performed when the main switch 24 is OFF, the system is abnormal, or the trailer is not pulled. That is, the auto cruise lamp 38 is turned off to notify the driver that the vehicle is not ready for constant speed travel. Then, the process proceeds to step 18 where the constant speed traveling is canceled.
[0034]
According to the processing of step 11 to step 19, the configuration for detecting the trailer pulling state is different from that of the first embodiment, but the operation and effect thereof are the same as those of the first embodiment.
[0035]
In the first to third embodiments described above, is the constant speed running condition established based on the signals from the main switch 24, the coupler switch 22, the brake pedal switch 28, the clutch pedal switch 30, and the like? However, the present invention is not limited to such a configuration. That is, since the constant speed traveling condition varies depending on the equipment of the tractor 10, the optimum condition according to the equipment should be determined.
[0036]
【The invention's effect】
As described above, according to the first aspect of the present invention, even when the road surface resistance is low, such as in rainy weather, the drive wheels are prevented from idling and the driving safety can be improved. it can.
[0037]
According to the second aspect of the present invention, since the trailer pulling state is detected by the existing parts, an increase in cost can be suppressed.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a first embodiment of a constant speed traveling device. FIG. 2 shows a coupler attached to a tractor, (A) is a perspective view, and (B) is a view in the direction A in FIG. FIG. 3 is a flowchart showing the contents of control in the first embodiment. FIG. 4 is a configuration diagram showing a second embodiment of the constant speed traveling device. FIG. 5 is a configuration diagram showing a third embodiment of the constant speed traveling device. FIG. 6 is a flowchart showing control contents in the second and third embodiments.
10 Tractor 14 Coupler 20 Engine control unit 22 Coupler switch

Claims (2)

Constant speed traveling condition determining means for determining whether or not the constant speed traveling condition is satisfied;
Traction state detection means for detecting the traction state of the trailer;
Only when it is determined that the constant speed traveling condition is established by the constant speed traveling condition determining means and the trailer traction state is detected by the traction state detecting means, the constant speed is maintained so as to maintain the set constant vehicle speed. A constant speed traveling means for traveling;
A tractor constant-speed traveling device characterized by comprising: The tractor constant-speed traveling device according to claim 1, wherein the traction state detecting means is a coupler switch attached to a coupler for connecting a trailer.

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