JP4416063B2 - Method and apparatus for clutch cut-off of transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a clutch cut-off method and apparatus for a transmission in a wheeled industrial vehicle such as a wheel loader, in particular, a clutch that can be cut off by depressing a brake pedal.
[0002]
[Prior art]
In a wheeled industrial vehicle, if you want to drive the vehicle little by little while stepping on the brake and want to keep the engine speed high to use the work implement, install a pressure switch in the brake pressure circuit, 2. Description of the Related Art A clutch cut-off device is widely used in which a transmission clutch is cut (cut off) without operating a forward / reverse shift lever.
[0003]
FIG. 6 shows an example. When the operator depresses the brake pedal 1a of the brake 1, air pressure is supplied from the air tank 1b to the air circuit, and the air pressure is converted into hydraulic pressure by the power cluster 2, and the brake tank 2a. In the brake device in which the braking force by the liquid is obtained, a pressure switch 3 is provided in the air circuit, and each solenoid for operating ON / OFF of each forward or reverse clutch 4 through the pressure switch 3 is provided. 5 and 6 are supplied with current.
[0004]
When a certain air pressure is generated in the air circuit by the brake operation, this is detected by the pressure switch 3, the current to the solenoids 5 and 6 is turned off, and the solenoids 5 and 6 are made neutral. The power transmission is cut off with 4 being neutral.
[0005]
However, in the above-described cut-off device, since the value of the air pressure for cutting off the solenoids 4 and 5 is constant, the brake depression angle at the time of cut-off is constant, and the brake operating force obtained at the time of cut-off is also This may occur only with a constant force, which may cause a problem that the vehicle may move backward for a moment during braking in a climbing operation or may not be able to smoothly decelerate when approaching a dump truck with a load.
[0006]
For example, Japanese Utility Model Publication No. 6-30540 discloses a conventional technique for solving the above problems. In this prior art, as shown in FIG. 7, the pressure switch is replaced with a pressure sensor 7, and a dial type variable setting device 8 that can be easily operated by an operator at the driver's seat is added. When the power from the setting device 8 is compared and both values become equal, the transistor 10 and the relay 11 are operated by the action of the comparator 9, the power of the solenoids 5 and 6 is cut off, and the transmission becomes neutral. It has become.
[0007]
Another conventional technique is disclosed in Japanese Patent No. 2944686. This prior art is as shown in FIG. 8, and the operation amount of the brake pedal 1a of the brake 1 is detected at the voltage level by the brake pedal position detecting unit 12, and the detection by the brake pedal position detecting unit 12 is performed. The voltage level and the set voltage level set by the settable voltage adjusting unit 13 are compared, and it is determined by the determining unit 14 whether or not this value has become a predetermined value. The solenoid 17 of the solenoid valve 16 is operated to cut off. Reference numeral 18 denotes a disc brake.
[0008]
[Problems to be solved by the invention]
In both of the prior arts shown in FIGS. 7 and 8, the cutoff point is set in advance by the variable setting device 8 or the voltage adjusting unit 13, and therefore the cutoff point determined by this is set. May not always be an appropriate value.
[0009]
In other words, when working on a vehicle with a cut-off point set prior to work such as cargo handling work, it will be cut off before the brake is fully applied, or it will not be cut off even if the brake is fully applied. There is.
[0010]
For this reason, in the prior art, the variable setting device 8 and the voltage adjusting unit 13 have to be appropriately adjusted by trial and error after actually performing the work.
[0011]
The present invention has been considered in view of the above, and in an actual work such as loading or scraping, a clutch of a transmission that allows the operator to set a cut-off in a state that is sensuously deemed most appropriate. An object of the present invention is to provide a cut-off method and an apparatus therefor.
[0012]
[Means for solving the problems and effects]
In order to achieve the above object, a clutch cut-off method in a transmission according to the present invention operates a brake by actuating a brake pedal, and when the brake operating force at this time exceeds a predetermined value, In a transmission in which the clutch is cut off, when the brake is operated, the cutoff operation is performed by an input signal from the cutoff setting device, and the brake operating state at the time of the cutoff is stored as a cutoff setting value. During the subsequent driving work, the brake pedal input value of the brake pedal is compared with the cut-off setting value, and the cut-off is performed when the brake operation state input value exceeds the cut-off setting value. .
[0013]
According to this method, for example, when the vehicle is loaded on a wheeled industrial vehicle such as a wheel loader or is running while being scraped up, the vehicle travels by turning on the cut-off setting device while operating the brake. The direction clutch is cut off, the operator can feel the brake operation and the running speed at this time, and can stop the vehicle with the cut-off setting device at the optimal time. At this time, the vehicle is cut off, and when the brake is applied, the operator can set the cut-off in a state that the operator feels is most appropriate, and this cut-off is set only once. Therefore, it is possible to prevent re-setting by trial and error after setting the cut-off.
[0014]
In addition, the device for carrying out the above method is configured such that the brake is operated by operating the brake pedal, and the traveling clutch is cut off when the brake operating force at this time exceeds a predetermined value. In the transmission, the brake operating force detecting means for detecting the brake operating force, the input means for the cut-off signal, and the driving clutch are cut off by the input of the cut-off signal. It has a setting unit for setting the power as the cutoff brake setting operating force, and compares the cutoff brake setting operating force set by this setting means with the brake operating force detected by the brake operating force detection means, Clutch for running when brake operating force exceeds cut-off brake set operating force It has a configuration comprising a controller which is adapted to cut-off.
[0015]
According to this device, implementation and brake operation force detecting means, a brake actuating force setting means, made of a controller, the clutch cut-off method in the above-mentioned transmission of at with a simple configuration is an object of Tokoro period can do.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIGS. In the description of this embodiment, the same members as those of the prior art shown in FIGS.
[0017]
The brake pressure that rises when the brake pedal 1a of the brake 1 is depressed is detected as a voltage level by the pressure sensor 7 (hereinafter the same), and this brake pressure value P _B is input to the controller 20. The controller 20 is supplied with a cut-off signal S from a cut-off setting device 21.
[0018]
The controller 20 is configured as shown in FIG. 1, and the brake pressure value P _B from the pressure sensor 7 is input via the input processing circuit 22a and the input interface circuit 23. The cut-off signal S input from the cut-off setting device 21 is input via the input processing circuit 22b and the input interface circuit 23, and the brake pressure value when the cut-off signal S is input is determined by the setting unit 24. It is set as the cut-off set pressure value P _S. The solenoid of this cut-off set pressure value P _S set at the same time as the clutch output interface circuit solenoid drive circuit 26a of the clutch for forward or reverse running state through the 25, the forward or backward feed of the cut-off signal to 26b of 27a and 27b are cut off.
[0019]
On the other hand the cut-off setter 21 the cut-off set pressure value P _S which is set when the cut-off signal S is input from is stored in the storage unit (RAM) 27. And this stored cutoff set pressure value P _S is compared continuously by the comparison unit 28 with the braking pressure value P _B input when working, the brake pressure value P _B is the cutoff changed by operation of the brake pedal 1a A cut-off signal is output to the output interface circuit 25 when the set pressure value P _{S is} equal to or higher than P _S (P _B ≧ P _S ), and the forward or reverse clutch in the running state is cut off. In FIG. 1, 29 is a CPU for performing the above-described operation processing, and 30 is a ROM for setting a program.
[0020]
FIG. 2 shows another embodiment, which attempts to cut off according to the depression angle of the brake pedal instead of the brake pressure. In other words, stepping angle of the brake pedal 1a is detected by the pedal angle sensor 31, the pedal angle value theta _B is adapted to be input to the controller 20. The controller 20 receives a cut-off signal S ′ from a cut-off setter 21 ′.
[0021]
Similar to the embodiment described above the controller 20, are input via the pedal angle value theta _B input processing circuit 22a from the pedal angle sensor 31, an input interface circuit 23. The cut-off signal S ′ input from the cut-off setting device 21 ′ is input through the input processing circuit 22 b and the input interface circuit 23, and the pedal angle value θ _B when the cut-off signal is input is set as the setting unit. so that the cut-off set angle value theta _S as set by the time the clutch solenoid 26a for forward or reverse, the cutoff signal 26b are outputted at 24. At the same time, the cut-off setting angle value θ _S set when the offset signal S ′ is input from the cut-off setting device 21 ′ is stored in the storage unit (RAM) 27, and this value is stored in the brake pedal 1a. is a pedal angle values changed by the depression and theta _B constantly compared in comparator unit 28, the forward or reverse when the pedal angle value theta _B is turned cutoff set angle value theta _S or (θ _B ≧ θ _S) Cut-off symbols are output to the solenoids 26a and 26b of the clutch.
[0022]
In both of the above-described embodiments, when the vehicle is running, the cut-off setting devices 21 and 21 'are turned on while the brakes are being operated, so that the vehicle travels forward or backward, that is, the traveling direction in which the vehicle is traveling at that time The clutch is cut off and the vehicle is stopped by the brake operation.
[0023]
In this way, the operator can feel the operating condition of the brake and the traveling speed at this time, and can stop the vehicle by the cut-off setting devices 21 and 21 ′ at the optimum time. When the set value is reached, the vehicle is cut off. Therefore, this cut-off setting is in an optimum state, and only one cut-off setting is required, and subsequent trial and error are not required.
[0024]
Method so as to determine the cut-off by comparison with the braking pressure value P _B and the cut-off set pressure value P _S is as shown in the flow diagram of Figure 3, the brake pressure value P _B and the cut in step 1 The off-set pressure value P _S is compared. If P _B ≧ P _S , the transmission T / M is set to neutral [N] by cut-off in step 2.
[0025]
Further, the method of determining the cutoff by comparing the pedal angle value θ _B and the cutoff set angle value θ _S is as shown in the flowchart of FIG. 4. In step 1, the pedal angle θ _B and the cutoff angle are determined. The set angle value θ _S is compared, and if θ _B ≧ θ _S , the transmission T / M is made neutral [N] by cutoff in step 2.
[0026]
And the setting of the depression amount of the brake pedal for the actual cut-off in both the above embodiments is as shown in FIG.
[0027]
Vehicles that work with buckets while traveling, such as wheel loaders, are equipped with brake pedals on both the left and right sides. During normal driving, the brake pedal on the right side is operated alternately with the access pedal on the right side. Like to do. Then, while driving, the left brake pedal is operated while operating the accelerator pedal at the time of lifting or loading work such as earth and sand with the bucket. The brake pedal 1a in the description of the above-described embodiment is a left brake pedal when the vehicle in this embodiment is a wheel loader.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration of an embodiment of the present invention.
FIG. 2 is a configuration explanatory view showing another embodiment of the present invention.
FIG. 3 is a flowchart showing the control contents of the embodiment of the present invention.
FIG. 4 is a flowchart showing the control contents of another embodiment of the present invention.
FIG. 5 is a flowchart showing a method for setting a depression amount of a brake pedal.
FIG. 6 is a configuration explanatory view showing a general cut-off device.
FIG. 7 is a configuration explanatory view showing a conventional cut-off device.
FIG. 8 is a configuration explanatory view showing a conventional cut-off device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Brake, 1a ... Brake pedal, 1b ... Air tank, 2 ... Power cluster, 2a ... Brake tank, 3 ... Pressure switch, 4 ... Clutch, 5, 6 ... Solenoid, 7 ... Pressure switch, 8 ... Variable setting device, DESCRIPTION OF SYMBOLS 9 ... Comparator, 10 ... Transistor, 11 ... Relay, 12 ... Brake pedal position detection part, 13 ... Voltage adjustment part, 14 ... Discrimination part, 15 ... Hydraulic clutch, 16 ... Solenoid valve, 17 ... Solenoid, 18 ... Disc brake , 20, controller 21, 21 ′, cut-off setting device, 21 a, input processing circuit, 23, 25, interface circuit, 24, setting unit, 26 a, 26 b, solenoid drive circuit, 27, storage unit, 27 a, 27 b,. Solenoid, 28 ... comparison unit, 29 ... CPU, 30 ... ROM

Claims (2)

In the transmission in which the brake is operated by operating the brake pedal, and the clutch for traveling is cut off when the brake operating force at this time exceeds a predetermined value,
When the brake is activated, the cutoff operation is performed by an input signal from the cutoff setting device, and the brake operating state at the time of the cutoff is stored as a cutoff setting value.
During subsequent driving work, the brake pedal input value in the brake operation state was compared with the cut-off setting value, and the cut-off was performed when the brake operation state input value exceeded the cut-off setting value. A clutch cut-off method for a transmission. In the transmission in which the brake is operated by operating the brake pedal, and the clutch for traveling is cut off when the brake operating force at this time exceeds a predetermined value,
Brake operating force detecting means for detecting the brake operating force;
A means for inputting a cutoff signal;
The driving clutch is cut off by the cut-off signal input, and the brake operating force at the time of the cut-off signal input is set as the cut-off brake setting operating force. The cut-off brake set operating force is compared with the brake operating force detected by the brake-operating-force detecting means, and the driving clutch is cut off when the brake operating force exceeds the cut-off brake set operating force. A transmission clutch cut-off device comprising: a controller configured as described above.

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