JPS6127348A - Automatic speed change control device in industrial car - Google Patents

Abstract

PURPOSE:To economize in storage capacity by providing a storage area for storing data on speed change points and a storage area for storing data on linear functions for calculating a speed change point in a storage device. CONSTITUTION:RAM 17 is provided with a storage area for storing data on acceleration opening amounts theta0-theta3 and running velocities V01d-V33u and with a storage area for storing data A1-A12 on inclination for a linear function connecting the speed change points to each other as a parameter of each speed change point. Thus, it is not necessary to set the speed change condition data for the running velocities and the acceleration opening amount on each running velocity and acceleration opening amount as conventionally, so that the amount of data is very small to economize in storage capacity of a storage device.

Description

[Detailed Description of the Invention] Object of the Invention (Industrial Application Field) The present invention relates to a clutch control device for an industrial vehicle such as a forklift with an automatic transmission, and more specifically to a clutch control device for controlling the engagement of an automatic transmission clutch. It is related to.

(Prior art) In a forklift with an automatic transmission, a shift map for when the clutch for shifting generally changes from 1st speed (low speed) to 2nd speed (medium speed) and from 2nd speed (midway) to 3rd speed (high speed) (upshift). is a step-like shift boundary line L1. which determines the shift range where the shift clutch is shown by the solid line in FIG. ．． Steering control is performed according to L2.

On the other hand, when the shift clutch changes from 3rd gear to 2nd gear or from 2nd gear to 1st gear (downshift), the shift map is similar to the step-like map in which the shift clutch determines the shift range shown by the two-dot chain line in Figure 4. Switching is controlled according to shift boundary lines L3 to L4. .

Conventionally, for forklifts with automatic transmissions, the above-mentioned speed change map is created by presetting data on the speed change state for each traveling speed and accelerator opening amount of the forklift, one by one for each traveling speed and accelerator opening amount. was stored in the storage device.

(Problem to be Solved by the Invention) However, in the conventional speed change map, data on the speed change state for each traveling speed and accelerator opening amount that constitute the shifting map are provided one by one for each traveling speed and accelerator opening amount. As a result, when it is desired to change the gear shift point, the amount of data is large, and the changing operation requires a great deal of effort.

Furthermore, due to the large amount of data, it was technically possible to create only the above-mentioned step-by-step shift map. Therefore, since the shift state changes stepwise, in FIG. 4, the shift boundary line P1 is shown near the shift boundary line, especially the shift boundary line P1 where the shift state does not change with changes in the accelerator opening amount. P2 does not allow optimal gear shifting.

Structure of the Invention (Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention includes a plurality of speed change clutches, and a speed change clutch switching drive means for selectively connecting each of the speed change clutches. , a vehicle speed detector that detects the running speed of the vehicle, an accelerator opening detector that detects the amount of operation of the accelerator pedal, and accelerator opening m data and running speed data for each shift state by the shift clutch. At least 2 pieces of data for each shift point.
and a storage area for storing data for a linear function that uses the data of the shift points for each shift state as a parameter and determines each shift region connecting the shift points. Detection signals from the accelerator opening detector and the vehicle speed detector are input to calculate the accelerator opening m and the traveling speed, and the traveling speed and the data for the linear function are used to calculate the accelerator opening m and the traveling speed on the shift boundary line. A calculation means for calculating an accelerator opening amount, and a comparison between the accelerator opening ■ on the shift boundary line calculated by the calculation means and the accelerator opening m based on the accelerator opening detector to determine a shift region. The gist of the present invention is to provide an automatic transmission control device for an industrial vehicle, comprising a comparison and determination means, and a drive control means for operating the clutch switching drive means and connecting the corresponding transmission clutch based on the determination result of the comparison and determination means. It is something to do.

(Function) In other words, there is a storage area in which the data of the shift point consisting of accelerator opening m data and travel speed data is recorded in the storage device for each shift state by the shift clutch, and a storage area for recording the shift point data for each shift state. A storage area is provided for storing data for a linear function that uses data as parameters to calculate each shift point that determines each shift region connecting the shift points.

Then, the calculation means inputs the detection signals from the accelerator opening degree detector and the vehicle speed detector, calculates the accelerator opening amount and traveling speed at that time, and uses the traveling speed and the data for the linear function to find a position on the shift boundary line. Calculate the accelerator opening amount.

Next, the comparing and determining means compares the accelerator opening amount on the shift boundary line calculated by the calculation means with the accelerator opening amount based on the accelerator opening detector, and determines the shifting region.

Based on the result of this determination, the drive control means operates the clutch switching drive means to connect the corresponding gear shifting clutch.

As a result, there is no need to set data on the gear change state for each traveling speed and accelerator opening amount one by one as in the past, so the amount of data can be reduced to a very small amount. It becomes possible to save the storage capacity of the storage device. Moreover,
Since there is only a small amount of data, it is very easy to change the gear shift point.

In addition, each shift point for the traveling speed and accelerator opening is calculated individually and the shift state at that time is compared, so it is possible to always obtain a shift state suitable for R and improve operability. becomes.

(Embodiment) Next, a preferred embodiment in which the present invention is embodied in a forklift will be described below with reference to the drawings.

FIG. 1 shows a hydraulic and electrical block circuit diagram of a forklift. A clutch oil pump 1 is driven by an engine (not shown), and pressure fluid from the pump 1 is supplied to a regulator valve 2. This pressure fluid is then regulated to a constant pressure by a regulator valve 2 and supplied to a forward/reverse clutch switching valve 4 via a pressure control valve 3.

The forward/reverse clap switching valve 4 is turned on or off based on the operation of a clutch switching lever 5 provided at the driver's seat of the forklift vehicle, and supplies pressurized fluid to the forward/reverse clutch 6 to connect the forklift to drive the forklift forward or backward.

The pressure control valve 3 adjusts the pressure of the pressure fluid supplied to the forward/reverse clutch 6 and controls the connection state of the clutch 6, and opens and closes an electromagnetic valve provided in the pressure control valve 3. By driving, the pressure of the pressure fluid supplied to the forward/reverse clutch 6 is adjusted. This electromagnetic solenoid valve is driven and controlled by the Nm solenoid 7 of the same valve.

Therefore, N! By controlling the excitation of the i solenoid 7. The connection state of the forward/reverse clutch 6 is controlled.

When the solenoid 8a is de-energized, the three-speed switching solenoid valve 8, which serves as a clutch switching drive means, supplies the pressure fluid from the regulator valve 2 to the next-stage two-speed switching solenoid valve 9, which also serves as a clutch switching drive means. On the other hand, when energized, the pressure fluid is sent to the 3rd speed clutch (hereinafter referred to as 3rd speed clutch) 10c, and the forklift's 3rd speed (
Make a connection for high speed).

The two-speed switching solenoid valve 9 changes the speed of the forklift to 1
This is a valve for switching between high speed (low speed) and second speed (medium speed), and when the solenoid 9a is de-energized, the pressure fluid is transferred to the first speed clutch (hereinafter referred to as the first speed clutch) 1.
0a, the connection for the 1st speed of the forklift is connected, and conversely, when energized, the pressure fluid is connected to the clutch for the 2nd speed (hereinafter referred to as 2).
10b (referred to as a speed clutch) to establish a connection for second gear of the forklift.

Next, an electric circuit for driving and controlling the solenoids 7.8a and 9a to control the pressure of the pressure fluid supplied to the clutches 6.10a, 10b and 10C will be described.

An accelerator opening sensor 11, which serves as an accelerator opening detector, is composed of a potentiometer and detects the depression of the accelerator pedal 12. In this embodiment, the accelerator pedal 12 is not mechanically connected to the engine throttle that operates the engine throttle valve, and the accelerator pedal 12 is a pedal that is mechanically connected to the opening sensor 11.

A vehicle speed sensor 13 serving as a vehicle speed detector detects the rotational speed of the drive shaft of the forklift and outputs a detection signal thereof.

A central processing unit (hereinafter referred to as CPU) 14 serving as a performance means, a comparison/discrimination means, and a drive control means operates according to a control program stored in a read-only memory (hereinafter referred to as ROM) 15, and operates through an interface 16. Detection signals from the accelerator opening sensor 11 and vehicle speed sensor 13 are input.

Then, the CPU 14 determines whether or not the accelerator pedal 12 is depressed based on the detection signal from the accelerator opening sensor 11 and calculates the accelerator opening amount θ at that time. Calculate Vx. Then, the CPU 14 controls the opening degree of the engine throttle based on the calculated accelerator opening amount θ, and controls the engine rotation speed. Note that the throttle opening degree relative to the amount of depression of the accelerator pedal 12 is set in advance, and the data is stored in the ROM 15.

Further, the CPU 14 outputs a predetermined drive signal to a solenoid drive circuit (not shown) via the interface 16, and controls the M! of the electromagnetic solenoid valve via the drive circuit. 1 solenoid 7 is excitation controlled.

A readable and rewritable memory (hereinafter referred to as RAM) 17 as a storage device has a storage area for temporarily storing various calculation results of the CPU i4, as well as four accelerator opening degrees Mθ0. θ1°θ2. It has a storage area for storing data of θ3. Further, the RAM 17 stores travel speeds VO1d and VO2u for each downshift and upshift at the accelerator opening degree ff1eO.
, VO2d, VO3u data storage area, accelerator opening amount C) 1, travel speed for downshifting and upshifting V11d, V
Storage area for storing data of 12u, V12d, V13U, travel speed V21 for downshifting and upshifting at Axle U11 degrees mlθ2
d, storage area for storing data of V22u, V22d, and V23u, and accelerator opening degree ff1e
The running speed for each downshift and upshift in 3 is 11 mV31d, V32! u, V32
d, has a storage area for storing data of V33u.

Then, the data of this accelerator opening Fffffiθ0 to θ3 and the traveling speed VO1d, Vlld, V21d
, V31d data and a specific shift point PO1d, Plld, for downshifting from 2nd gear to 1st gear.
Data of P21d and P31d, data of accelerator opening le O~θ3 and traveling speed VO2d, V1
2d, V22d, V32d (7) Specific shift point P for downshifting from 3rd gear to 2nd gear with data
The data are O2d, P12d 4 P22d, P32d.

In addition, data on accelerator opening amount 00 to θ3 and traveling speed VO
Specific shift points PO2u, P12u, P22u, P32u for upshifting from 1st gear to 2nd gear with data of 2u, V12u, V22u, V32u
data of accelerator opening amount θO to θ3 and traveling speed V03u, V13u, V23u, V
33u data and a specific shift point PO3u for upshifting from 2nd gear to 3rd gear.

Let's assume that the data is P13u, P23u, and P33u.

Note that the data on each accelerator opening amount and each traveling speed are predetermined, and are determined, for example, according to the vehicle type or purpose of the forklift.

Roughly, the RAM 17 stores slope data A1 to A12 for linear functions F1 to [12] that connect the shift points using each shift point for each downshift and upshift as parameters. It has an area.

Each of the linear functions F1 to F12 is a function for connecting each shift point for each shift shown in FIG. The function “2 is “2−θx −A 2(
Vx - Vlld ) - C) 1, and the coefficient (inclination) A2 is the shift point piid, p21d
As a parameter, A2-(θ2-θ 1) / (V21d -Vllc
l).

Similarly, the linear function F12 connecting the shift point P 23u and the shift point P 33u and the coefficient (slope) A12 are F12 - θx = A12 ('Vx - V23u ) - θ
2A12= (e 3 - e 2) / (V33u -
V23u).

Then, the CPU 14 calculates respective coefficient (inclination) data A1 to AI2 based on the accelerator opening amount data and the traveling speed data that constitute the data of the shift point, and stores them in a predetermined storage area provided in the RAM 17. It looks like this.

Further, the CPU 14 calculates the accelerator opening at that time calculated based on the detection signal from the accelerator opening sensor 11, ft! where θ is partitioned by the accelerator opening group 00 to θ3 stored in the RΔM17. Box 1. Determine which range of Il and III it is in. Based on the determination result, the CPU i4 determines the range I of the opening amount to which the accelerator opening amount θ belongs,
Predetermined slope data of the linear functions F1 to F12 for each downshift and upshift in Lm is read from the RAM 17 from among the data A1 to A12, and the read slope data is combined with the slope data of the vehicle speed sensor 13. Based on the current traveling speed Vx calculated based on the detection signal, the accelerator opening amount θX at the shift point of the traveling speed Vx is calculated.

Then, the CPU 14 calculates the calculated accelerator opening degree mex.
The magnitude of the accelerator opening mθ at that time is compared to determine which shift range the accelerator opening mθ is at that time, and based on the determination result, a control signal is output to the solenoid drive circuit 18 to The speed changeover electromagnetic valve 8.9 is driven and controlled to achieve a predetermined speed change state.

Next, the operation of the forklift constructed as described above will be explained.

Now, while the 74-crit is running forward, the CPU
14 calculates the accelerator m1 degree θ" and the traveling speed ■× based on the detection signals from the accelerator opening sensor 11 and the vehicle speed sensor 13. Then, the CPU 14 first calculates which opening amount the accelerator opening 1e is. Each opening amount data θ0 stored in the RAM 17 whether it is in the ranges I, n, nu
Determine by comparing He with θ3.

Now, when it is determined that θ is in the range ■ of 1 and 02, the CPU 14 next moves from 2nd speed to 1st speed in this range ■.
The data of the shift points P11d and P21d, which are the parameters of the linear function F2 for downshifting to a lower speed, that is, the accelerator opening amount data θ1 and θ2 and the traveling speed data V11d and V21d are read out.

Next, the CPU 14 reads out the traveling speed data Vlld.
, V21d and the calculated running speed VX at that time are compared, that is, the running speed Vx is VX<Vlid 1.
It is determined whether V11d≦Vx≦V21d or Vx>V21d.

If VX < Vlld, the CPU 14 determines that the current state is in the 1st speed region, and if the current state is in the 1st speed region, it maintains the state as it is, and in other cases, it activates the solenoid to change to the 1st speed state. The third speed and second speed solenoid valves 8 and 9 are driven through the drive circuit 18 to connect the first speed clutch 10a.

On the other hand, if Vx>V21d, the CPU 14 is within the range ■
Shift points P12d and P2 are parameters of the linear function F8 for downshifting from 3rd gear to 2nd gear in
2d data, that is, accelerator opening amount data e1.
θ2 and traveling speed data V12d.

The arithmetic processing unit which reads V22d and will be described later is executed.

On the other hand, if Vlld ≦Vx ≦V21d, the CPU
14 reads out coefficient (slope) data A2 of the linear function F2 for downshifting from second gear to first gear in range ■. Then, the CPU 14 uses this coefficient data A2, the accelerator opening amount θ at that time, the traveling speed UVx, and rj, and the shift point P11d (7) Ijiflt! Substituting Cheetaro 1' and traveling speed data V11d into linear function F2,
The accelerator opening degree 54ex at the shift point px at the current traveling speed VX is calculated.

Next, the CPU 14 compares the accelerator opening degree ff1 e'x with the accelerator opening amount θ based on the accelerator pedal 12. If CPU 4 determines that ex≦e, the CPU 14 determines that the current state is in the 1st speed region, and if the current state is in the 13V region, maintains the state as it is, otherwise changes to the 1st speed state. The third speed and second speed solenoid valves 8.9 are driven via the solenoid drive circuit 18 to connect the first speed clutch 10a and change gears.

On the other hand, if ex>θ, C and P U 14 are maintained in the 1st or 2nd speed state when the current state is in the 1st or 2nd speed region, and when the current state is in the 3rd speed region. In this state, the third speed and second speed electromagnetic valves 8 and 9 are driven via the solenoid drive circuit 18 to connect the second speed clutch 1ob to change the speed.

Next, the case where Vx≧V 21d will be described.

First, the CPU 14 generates data on shift points P12d and P22d, which are parameters of the linear function F8 for downshifting from 3rd gear to 2nd gear in range 2, that is, accelerator opening amount data θ 1. θ2 and traveling speed data V
12d, read V22d. And CPU14
As above, the running speed Vx is Vx <V12d,
V12d≦Vx≦V22d, or Vx>V22d
Determine which category it belongs to.

Then, in the case of v12d≦Vx≦V22d, the CPU 14 reads coefficient (slope) data 88 of the linear function F8 for downshifting from 3rd gear to 2nd gear in the range ■, in the same manner as described above. Then, the CPU 14 substitutes this coefficient data 88, the accelerator opening amount e at that time, the traveling speed, the opening amount data θ1 at the shift point P12d, and the traveling speed data V12d into the linear function F8, and The accelerator opening amount θX at the shift point Px at the speed lit V y is calculated.

Then, the CPU 14 compares the accelerator opening amount θX with the accelerator opening amount θ based on the accelerator pedal 12. If θX>θ, the CPU 14 maintains the current state when the current state is in the 2nd speed region or 3rd speed region, and changes to the 2nd speed state when the current state is in the 1st speed region. Shift.

On the other hand, when θ×≦θ, the CPU 14 maintains the 2nd speed state when the current state is in the 2nd speed region, and maintains the 2nd speed state as it is when the current state is in the 1st speed region or 3rd speed region. shifts to 2nd gear.

On the other hand, when VX<V12d, the CPU 14 selects a shift point P12u which becomes a parameter of a linear function F5 for upshifting from 1st to 2nd speed in range ■.

P 22u data, Zunawara, accelerator opening amount data e 1. θ2 and traveling speed data V12u, V22
Read u.

Based on these data, the magnitudes of θX and e are compared to determine the shift state. In the case of θ×〉θ, when the current state is in the 1st or 3rd speed region, the gear is shifted to the 2nd speed, and when the current state is in the 2nd speed region, the state remains unchanged. maintained. On the other hand, in the case of θ×≦θ, when the current state is in the 1st or 2nd speed region, the 1st or 2nd speed state is maintained as it is, and when the current state is in the 3rd speed region The gear is shifted to 2nd gear.

In addition, in the case of Vx>V22d, the CPU 14 generates a linear function F for upshifting from 2nd to 3rd speed in the range ■.
Shift point P13u is the parameter No. 11.

p 23tl data, Zunawachi, accelerator opening amount data e 1.02 and traveling speed 7''-YV13u, V
Read 23t+.

Then, based on these data, the magnitudes of θX and θ are compared to determine the shift state. In the case of θX≦θ, when the current state is in the 2nd or 3rd speed region, the 2nd or 3rd speed state is maintained as it is, and when the current state is in the 1st speed region, the 2nd or 3rd speed state is maintained. The gear is shifted to a high speed state. On the other hand, in the case of θX>θ, when the current state is in the 1st or 2nd speed region, the gear is shifted to the 3rd speed state, and when the current state is in the 3rd speed region, it remains in the 3rd speed state. will be maintained.

As described above, in this embodiment, a specific shift point is set in advance for each downshift and upshift, and the accelerator opening amount data and travel speed data that form the shift point, and each of these data are determined as parameters. A linear function [-1 to coefficient (slope) for 12] A1-A12 that determines each shift region connecting the shift points.
The shift point for each driving condition is determined based on the data of
Since the gear change state was determined based on the determined value,
Unlike in the past, there is no need to set the data on the shifting state that is important for each traveling speed and the amount of the axle opening one by one for each traveling speed and the amount of the axle opening. Capacity can be saved. Moreover, since there is little data, if you want to change the shift point, you can do it very easily.

Further, since each shift point for the traveling speed and the accelerator opening amount is calculated individually and the shift state at that time is compared, the most suitable shift state can always be obtained.

In this embodiment, the case where the accelerator opening degree ff>e is in the range (2) has been described, but the same procedure can be performed in other ranges (2).

Further, in this embodiment, the case of shifting from 1st speed to 3''a will be described, but the number of shiftings may be further increased or decreased.

Furthermore, although the present embodiment has been described by setting four shift points for each shift, this number may be increased or decreased as appropriate.

Effects of the Invention As detailed above, according to the present invention, there is no need to set data on the speed change state for each traveling speed and accelerator opening amount one by one, as in the conventional case. However, the amount of data can be made very small, and the storage capacity of the storage device U can be saved. Moreover, since there is little data, if you want to change the shift point, you can do it very easily.

Furthermore, since each shift point for the traveling speed and accelerator opening is calculated individually and the shift state at that time is compared, the optimum shift state can always be obtained and operability can be improved.

[Brief explanation of the drawing]

Figure 1 is a hydraulic and electrical block circuit diagram of a forklift embodying this invention, Figure 2 is a diagram showing the contents of a readable and rewritable memory (RAM), and Figure 3 is a diagram showing the accelerator opening amount and traveling speed. FIG. 4 is a diagram showing a conventional speed change range based on the accelerator opening amount and traveling speed. In the figure, 8 is a 3-speed switching solenoid valve, 9 is a 2-speed switching solenoid valve, 10a is a 1st-speed clutch, 10b is a 2nd-speed clutch, 1
0c is the 3rd speed clutch, 11 is the accelerator opening sensor, 13
゛ is a vehicle speed sensor, 14 is a central processing unit (CPtJ), 1
7 is readable and rewritable memory ('RAM)
It is. Patent applicant: Toyota Industries Corporation Fuji
General Co., Ltd. Representative Hironobu Patent Attorney Figure 2 Figure 8 '02u ■12L+ v22u V32uVO2
d V+2d V22dV32dVO3u V
13u V23u V33u running? TI-Ichiga

Claims (1)

[Scope of Claims] A plurality of shift clutches, a shift clutch switching drive means for switching and connecting the respective shift clutches, a vehicle speed detector for detecting the running speed of the vehicle, and a vehicle speed detector for detecting the operating speed of the accelerator pedal. an accelerator opening detector for detecting; a storage area for storing at least two pieces of shift point data each consisting of accelerator opening amount data and travel speed data for each shift state by the shift clutch; a storage device having a storage area for storing data for a linear function for calculating each shift point that determines each shift region connecting the shift points, using the data of each shift point as a parameter; and the accelerator opening degree detector. and a calculation means that calculates an accelerator opening amount and a traveling speed by inputting a detection signal from a vehicle speed detector, and calculates an accelerator opening amount on a shift boundary line using the traveling speed and data for the linear function; a comparison determination means for determining a shift region by comparing the magnitude of the accelerator opening amount on the shift boundary line calculated by the calculation means and the accelerator opening amount based on the accelerator opening detector; and a determination result of the comparison determination means. 1. An automatic transmission control device for an industrial vehicle, comprising: drive control means for operating said clutch switching drive means and connecting a corresponding transmission clutch based on said clutch switching drive means.