JP2000213636A - Industrial vehicles - Google Patents

Abstract

(57) [Problem] An object of the present invention is to provide an industrial vehicle that can easily cope with various situations and can improve workability. A traveling speed detector detects the speed of a vehicle.
A shift-hold / select switch 32 for selecting a first-speed fixed mode using only the first-speed gear, a second-speed fixed mode using only the second-speed gear, and an automatic mode; and when the automatic mode is selected, Fast
Auto transmission mode to select "economy mode" for automatic gear shifting using third gear and "power mode" for automatic gear shifting using first, second, and third gear.
Based on the select switch 33, the detected vehicle speed and the mode selected by the select switches 32 and 33,
The vehicle includes a control device 31 that controls a transmission shift. With this configuration, it is possible to easily select a mode corresponding to various situations, and it is possible to improve workability by automatic gear shifting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an industrial vehicle provided with a transmission.

[0002]

2. Description of the Related Art Transmission systems for industrial vehicles can be roughly divided into two types: a torque control transmission system and a hydrostatic pump (hereinafter referred to as HST).
There is a method of shifting the speed of a transmission connected to a hydraulic drive motor (hereinafter abbreviated as an HST motor) driven by a pump. Hereinafter, the transmission system of the HST motor will be described.

Conventionally, an HST pump directly connected to an engine and an HST motor driven by the pump are provided.
In an industrial vehicle provided with a transmission connected to the HST motor and driving an axle, the engine speed is controlled by operating an accelerator pedal to control the rotation of the HST motor, or the discharge from the HST pump to the HST motor. The rotation of the HST motor is controlled by controlling the angle of the swash plate of the HST pump for setting the amount of hydraulic oil to be set, and the speed of the vehicle is adjusted by shifting the transmission.

[0004] The configuration of the main part of the above-mentioned conventional industrial vehicle will be described in detail with reference to FIG.

In FIG. 5, reference numeral 1 denotes an engine whose rotation speed is controlled by operating an accelerator pedal 2. The engine 1 supplies an HST pump 3, a boom, a bucket and the like to supply oil to a main circuit of a cargo handling device. The pump 4 and the charging pump 5 are directly connected.

The HST pump 3 is a pump whose stroke (not shown) changes due to the swash plate 6 and the amount of hydraulic oil discharged to the HST motor 7 changes as described above. By controlling the angle setting of the swash plate 6, the rotation speed of the HST motor 7 is controlled. The charging pump 5 supplies hydraulic oil to the HST control valve 10 of the swash plate 6.

The HST control valve 10 generates a pressure difference between the two supports of the servo cylinder 9 by the operating oil from the charging pump 5 in accordance with the selection operation of the direction change lever between forward, neutral and reverse. Also HST
Solenoid valve for inching control valve 10
11 is driven by an inching detection pressure sensor 13 for detecting the operation of the brake pedal 12, the servo cylinder 9
Is adjusted, and the angle of the swash plate 6 is reduced irrespective of the rotation speed of the engine 1, and the vehicle is slowed down or stopped.

The operation of the above configuration will be described.

First, when the engine 1 rotates, the hydraulic oil discharged from the charging pump 5 is supplied to the HST control valve 10, and when the direction change lever is operated to the forward or reverse position, the pressure difference is reduced to the servo cylinder 9. (This pressure difference becomes the control pressure of the servo cylinder 9). Next, when the accelerator pedal 2 is depressed, the rotation speed of the engine 1 increases, the discharge amount of the working oil of the charging pump 5 increases, and the control pressure increases. When the control pressure reaches a force for operating the swash plate 6, the swash plate 6 of the HST pump 3 rotates, and the hydraulic oil is discharged from the HST pump 3 to the HST motor 7, and the vehicle moves forward or backward. The hydraulic oil discharged from the main pump 4 at this time is supplied to the main circuit of the cargo handling device.

When the brake pedal 12 is operated,
The inching solenoid valve 11 is driven via the inching detection pressure sensor 13, the control pressure to the servo cylinder 9 is adjusted, and the angle of the swash plate 6 decreases irrespective of the number of revolutions of the engine 1, so that the vehicle is slow or stopped. I do. Further, when a load is applied to the vehicle, the force of the swash plate 6 of the HST pump 3 to return to neutral increases, the angle of the swash plate 6 decreases, and the speed of the vehicle automatically decreases.

As shown in FIG. 5, one shaft of a transmission 15 is connected to the shaft of the HST motor 7, and an axle 16 is connected to the other shaft of the transmission 21, and a parking brake is connected to the axle 16. 17 and service brake (disk brake) 18 are installed. The parking brake 17 is driven by a parking brake knob 19, and the service brake 18 is driven via a master cylinder 20 by operating the brake pedal 12. Also,
The speed stage of the transmission 15 is selected by operating a transmission change lever, and the transmission 15 is shifted. In FIG. 5, reference numeral 21 denotes a traveling speed detector (an example of speed detecting means) for detecting the speed of the vehicle by detecting the rotation speed of the axle 16 (vehicle speed frequency).

[0012]

However, in such an industrial vehicle, a gear change operation is frequently performed by a transmission change lever in order to repeatedly perform a cargo handling operation and a traveling operation. Since the shift operation must be performed in response to various situations such as a slope, there is a problem that workability is poor and a burden on the operator is large.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an industrial vehicle which can easily cope with various situations and can improve workability.

[0014]

According to one aspect of the present invention, there is provided an industrial vehicle provided with a transmission, wherein the speed detecting device detects a speed of the vehicle. Means, a first-speed fixed mode using only the first-speed gear of the transmission, a second-speed fixed mode using only the second-speed gear of the transmission, and an economy mode for automatically shifting using the high-speed gear of the transmission. Selecting means for selecting a power mode in which automatic transmission is performed by using all gears of the transmission; and, based on a speed of the vehicle detected by the speed detecting means and a mode selected by the selecting means, It is characterized by comprising a control means for controlling a shift of the transmission.

According to the above configuration, the "first speed fixed mode" using the first speed gear which is effective when working in a narrow place, on a slope, or when strong engine braking is required, such as inboard work, or the maximum speed There is no limit, there is no shift point and there is no brake point overlap and no shift shock occurs, so the 2nd gear fixed mode uses the optimal 2nd gear when carrying unstable or luggage or precision luggage. '' Or `` Power mode '' that uses all gears to automatically shift when using heavy loads or low-speed driving when driving in automatic mode, or shifting when driving in automatic mode `` Economy '' that uses high-speed gears and automatically shifts, with less shock, excellent acceleration, and thus expected to improve work efficiency and fuel efficiency Over de "is selected, the shift of the transmission is performed based on the speed of the selected mode and the vehicle. The above modes can be selected according to various road conditions such as a difference in work status between a load and no load or a slope, that is, it can easily cope with various situations. Since it is not necessary to perform the operation, the workability can be improved, and the burden on the worker can be reduced.

The invention according to claim 2 of the present invention provides:
2. The invention according to claim 1, wherein in the economy mode, a second-speed gear and a third-speed gear of the transmission are used, and when the economy mode is selected, the second gear and the third-speed gear are used. A shift point at which a gear is switched is set to a lower speed than the shift point in the power mode.

According to the above configuration, the acceleration is further improved, and the fuel efficiency is improved.

Further, the invention according to claim 3 of the present invention provides
3. The vehicle according to claim 1, wherein the control means is configured to control the vehicle when the first speed fixed mode or the second speed fixed mode is selected by the selection means during operation from the economy mode or the power mode. Is reduced to a speed range in which the first-speed gear or the second-speed gear is used, and thereafter, the mode shifts to the selected first-speed fixed mode or second-speed fixed mode.

According to the above configuration, the speed is reduced to a safe speed, and the gear is switched to the selected fixed mode gear. Therefore, the shock due to the shift is eliminated, and the collapse of the load is prevented.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. The same components as those of the conventional example shown in FIG. 5 are denoted by the same reference numerals, and description thereof is omitted.

FIG. 1 is a main part control configuration diagram of an industrial vehicle showing an embodiment of the present invention.

In FIG. 1, reference numeral 31 denotes a control device (an example of a control means) which controls a speed mode signal selected by operating a shift hold / select switch (an example of a selection means) 32 provided in a driver's seat, and a driver's seat. The automatic transmission mode select switch (an example of a selection means) 33 provided in the automatic transmission speed mode signal selected by the operation of the 33 and the vehicle speed signal of the traveling speed detector 21 is input, the transmission
Solenoid valve 3 for 15 1st and 3rd speed clutch
Controls solenoid valves 4 and 35 and inching solenoid valve 11.

The shift hold / select switch 32
Selects "1st gear fixed mode", "2nd gear fixed mode", and "automatic mode". When "automatic mode" is selected by the auto mission mode select switch 33, "economy mode" and "automatic mode" are selected. "Power mode" is selected.

The above-mentioned solenoid valves for each speed stage clutch
Hydraulic oil supplied from the charging pump 5 is supplied to the first and third gears 1ST and 3RD and supplied to the first and third gears 3ST and 3RD. When none of the third speed clutch clutch valves 34, 35 is selected, the hydraulic oil is supplied to the second gear 2ND, and the second gear is selected.

FIG. 4 shows the relationship between vehicle speed and driving force in each gear. In the "power mode", the first-gear-second-gear shifting is performed at 8 km / h, the second-gear-third-gear shifting is performed at 17 km / h, and the shift point uses engine torque effectively. Is set to Further, in the "economy mode", the second gear and the third gear are shifted at a speed of 13 km / h, and the shift point is set earlier than in the power mode.

FIGS. 2 and 3 are block diagrams of the control device 31.
Shown in

As shown in FIG. 3, in order to detect a shift point, the traveling speed detector 21 turns on when the vehicle speed is greater than 13 km, and turns off when the vehicle speed is less than 11 km.
A comparator 41 that excites the relay # E23 when on, a comparator 42 that turns on when the vehicle speed of the traveling speed detector 21 exceeds 8 km, turns off when the vehicle speed is less than 6 km, and a comparator 42 that excites the relay # P12 when on. A comparator 43 is provided which turns on when the vehicle speed of the traveling speed detector 21 is higher than 17 km, turns off when the vehicle speed is lower than 15 km, and excites the relay # P23 when the vehicle speed is on.

As shown in FIG. 2, operation switches 32,
In response to the operation signals of the 33 switches, the relay # 1S in the “first speed fixed mode” and the relay # 2 in the “second speed fixed mode”
S, a relay #AE of the "economy mode" and a relay #AP of the "power mode" are provided.

Further, when the "first speed fixed mode" is selected, when the vehicle speed of the traveling speed detector 21 is greater than 8 km (when relay # 1S is on and relay # P12 is on), or "second speed fixed mode" is selected. When "Mode" is selected,
When the vehicle speed of the traveling speed detector 21 is greater than 13 km (when the relay # 2S is on and the relay # E23 is on)
A relay #LCK to be excited is provided.
When the LCK operates (turns on), an operation signal is output to the inching solenoid valve 11. Therefore, when shifting to the first speed or second speed fixed mode, if the speed range of the gears in these modes is exceeded, the inching solenoid valve 11 is driven, the control pressure to the servo cylinder 9 is adjusted, and the engine 1 Irrespective of the rotation speed of the motor, the angle of the swash plate 6 is reduced, the rotation speed n of the HST motor 7 is reduced, and the vehicle is decelerated.

Further, when the "first speed fixed mode" is selected, when the vehicle speed of the traveling speed detector 21 is smaller than 8 km (when relay # 1S is on and relay # P12 is off), or "second speed fixed mode" is selected. When "Mode" is selected,
When the vehicle speed of the traveling speed detector 21 is lower than 13 km (when the relay # 2S is on and the relay # E23 is off)
A relay #CHG that is excited in the power supply is provided, and a relay #AE in the "economy mode" and a relay #AE in the "power mode" are provided.
The AP is reset when the relay #CHG operates (turns on). 44 and 45 are RS flip-flops.

Therefore, relay #AE and relay #AP are
In the state where the relay #AE and the relay #AP are set, the "first speed fixed mode" or the "second speed fixed mode"
Even if is selected, it will not be reset until it is reduced to the speed range of these fixed mode gears,
The condition is maintained to prevent a sudden shift shock.

As shown in FIG. 3, for the solenoid valve 34 for the first-speed speed gear clutch, the "first speed fixed mode" is selected (relay # 1S ON) and not the "economy mode" (relay #AE). Off) and "power mode"
(Relay #AP off) or when "power mode" is selected (relay #AP on) and the vehicle speed of the traveling speed detector 21 is less than 8 km (relay # P1)
2 OFF), a signal is output, and the first-speed clutch valve 34 for the speed gear is excited.

The economy mode is selected (relay #AE on) and the vehicle speed of the traveling speed detector 21 is set to 13k for the solenoid valve 35 for the third speed speed clutch.
m (relay # E23 on), the "power mode" is selected (relay #AP on), and the vehicle speed of the traveling speed detector 21 is greater than 17 km (relay # E23).
(P23 ON), a signal is output, and the solenoid valve 35 for the third speed clutch is excited.

The operation of the above configuration will be described.

First, when the engine 1 rotates, the hydraulic oil discharged from the charging pump 5 is supplied to the HST control valve 10 and the transmission control valve 37.
When the direction change lever is operated to the forward or reverse position, a pressure difference is applied to both ports of the servo cylinder 9 (this pressure difference becomes a control pressure of the servo cylinder 9). Driving in "1st-speed fixed mode" In this state (the vehicle is stopped), when "1st-speed fixed mode" is selected by the shift hold / select switch 32,
The relay # 1S is excited, the first-speed speed-stage clutch solenoid valve 34 is excited by the control device 31, hydraulic fluid is supplied to the first-speed gear 1ST, and the first-speed gear of the transmission 15 is connected.

Next, when the accelerator pedal 2 is depressed, the rotation speed of the engine 1 increases, the discharge amount of the working oil of the charging pump 5 increases, and the control pressure increases. When the control pressure reaches a force for operating the swash plate 6, the swash plate 6 of the HST pump 3 rotates,
Hydraulic oil is discharged from the pump 3 to the HST motor 7,
The T motor 7 is driven, the axle 16 is driven via the first gear of the transmission 15, and the vehicle moves forward or backward. Also,
At this time, the hydraulic oil discharged from the main pump 4 is supplied to the main circuit.

When the brake pedal 12 is operated,
The service brake 18 is driven via the master cylinder 20, the inching solenoid valve 11 is driven via the inching detection pressure sensor 13, the control pressure to the servo cylinder 9 is adjusted, and the However, the angle of the swash plate 6 decreases, the rotation speed of the HST motor 7 decreases, and the vehicle moves at a low speed or stops. Also,
When a load is applied to the vehicle, the force of returning the neutral to the swash plate 6 of the HST pump 3 increases, the angle of the swash plate 6 decreases, and the speed of the vehicle automatically decreases.

Thus, in the "first speed fixed mode",
Only high gear is used. Although this mode can only run at low speed, it has a large driving force, so it is effective when working in narrow places such as onboard work, working on slopes, or when strong engine braking is required. Operation in "2nd fixed mode" When "2nd fixed mode" is selected by the shift hold select switch 32, the relay # 2S is excited, and when the relay # 2S is turned on, the first and third speed stages are set. Since both of the clutch solenoid valves 34 and 35 are not excited, the hydraulic oil is supplied to the second gear 2 of the transmission 15 as shown in FIG.
ND, and the second gear is connected. Other operations are the same as those in the “first speed fixed mode”.

As described above, in the "second speed fixed mode",
Only high gear is used. It is effective for use when there is a maximum speed limit, and since there is no shift point and the brake point does not overlap and shift shock occurs,
Ideal for carrying unstable or luggage or precision luggage. Operation in "power mode" If "automatic mode" is selected by the shift hold select switch 32 and "power mode" is selected by the auto mission mode select switch 33 at this time, the relay #AP is excited. Initially, relay #P that detects the shift point in power mode
Since both # 12 and # P23 are off, the control device 31 excites the first speed solenoid clutch valve 34 for the speed gear clutch, supplies hydraulic oil to the first speed gear 1ST, and connects the first speed gear of the transmission 15 to the first speed gear 1ST. You.

When the accelerator pedal 2 is depressed and the speed of the vehicle increases, and the relay # P12 operates beyond the shift point of the power mode, the solenoid valves 34 and 35 for the first-speed and third-speed clutches for speed gears are activated. Both are non-excited, and the second speed gear is connected. Then, when the speed of the vehicle further increases and the relay # P23 operates beyond the shift point in the power mode, the solenoid valve 35 for the third speed clutch is excited by the control device 31, and the hydraulic oil is transferred to the third gear 3RD. The third gear of the transmission 15 is connected.

When the relay is decelerated and the relay # P23 is turned off, the solenoid valves 34 and 35 for the first-speed and third-speed clutches are not excited, and the second-speed gear is connected. When the relay # P12 is further turned off and the relay # P12 is turned off, the first-speed speed-stage clutch solenoid valve 34 is excited by the control device 31, and the operating oil is supplied to the first-speed gear 1S.
, And the first gear of the transmission 15 is connected.

As described above, in the "power mode", the first gear, the second gear, and the third gear are automatically shifted. This "power mode"
This is effective when the load is large and traveling at low speed is required.

When the "power mode" is selected (relay #AP is ON) and the "first speed fixed mode" or the "second speed fixed mode" is selected by the shift / hold select switch 32, If the speed range of 1st or 2nd fixed mode gear is exceeded, relay #
When LCK is excited, the inching solenoid valve 11 is driven, the control pressure to the servo cylinder 9 is adjusted, and the angle of the swash plate 6 decreases regardless of the engine speed, and the speed n of the HST motor 7 decreases. Is reduced and the vehicle is decelerated. When the speed is reduced to the speed range of the selected fixed mode gear, the relay #CHG is excited,
The relay #AP is reset, and shifts to the selected fixed mode. Therefore, the shift shock is prevented, and the collapse of the load can be prevented. Operation in "Economy Mode" If the "automatic mode" is selected by the shift hold select switch 32 and the "economy mode" is selected by the auto transmission mode select switch 33, the relay #AE is excited.
At first, the relay # E23 for detecting the shift point in the economy mode is off, so that the solenoid valves 34 and 35 for the first-speed and third-speed clutches are non-excited, so that they operate as shown in FIG. The oil is supplied to the second gear 2ND of the transmission 15, and the second gear is connected.

Then, when the accelerator pedal 2 is depressed to increase the speed of the vehicle and the relay # E23 operates beyond the shift point in the economy mode, the control device 31 excites the solenoid valve 35 for the third speed clutch. The operating oil is supplied to the third speed gear 3RD, and the transmission 15-3
The speed gear is connected. Also slowed down, relay #E again
When the switch 23 is turned off, the first and third speed stage clutch solenoid valves 34 and 35 are both de-energized, and the second speed gear is connected.

As described above, in the "economy mode",
The automatic shifting of the second gear and the third gear is performed. As shown in FIG. 4, the shift of the second gear and the third gear is performed at 13 km (speed), and the shift point is set earlier than the power mode.
Has less shift shock and is excellent in acceleration, so that improvement in working efficiency and improvement in fuel efficiency can be expected.

When the "economy mode" is selected (relay #AE is on), the shift hold select switch 32 is used to set the "first speed fixed mode" or "2 speed fixed mode".
When "speed fixed mode" is selected, these 1st speed or 2nd speed
If the speed exceeds the speed range of the gear in the fixed speed mode, the inching solenoid valve 11 is driven, the control pressure to the servo cylinder 9 is adjusted, and the angle of the swash plate 6 decreases regardless of the engine speed. HST motor 7
Is decreased, and the vehicle is decelerated. When the speed is reduced to the speed range of the fixed mode gear, the relay #
The AE is reset and shifts to the selected fixed mode. Therefore, the shift shock is prevented, and the collapse of the load can be prevented.

As described above, the shift hold select switch 32 and the auto mission mode select switch 33 allow each mode to be selected in accordance with the difference in work conditions due to load and no load, and various road conditions such as a slope. That is, it can easily respond to various situations,
Further, in these modes, since there is no need for the operator to change gears, workability can be improved and the burden on the operator can be reduced.

Even when the control device 31 has failed for some reason, the solenoid valves 34 and 35 for the speed gear clutch are both de-energized and the vehicle can be moved by connecting the second gear. .

In the above embodiment, the rotation speed n of the HST motor 7 is reduced by driving the inching solenoid valve 11 when the vehicle is decelerated, but the service brake 18 is operated or the engine 1 The rotation speed n of the HST motor 7 can be reduced and decelerated by other methods such as controlling the rotation speed to decrease.

Means for selecting each mode (shift hold select switch 32 and auto transmission mode
Although the select switch 33) is a switch type,
A lever type can also be used. With lever type,
When switching modes frequently, the operation efficiency is improved.

In the above embodiment, the transmission system of the HST motor has been described. However, the present invention can be applied to a torque transmission system, and similar effects can be expected.

[0052]

As described above, according to the present invention, it is possible to provide an industrial vehicle capable of easily coping with various situations and improving workability.

[Brief description of the drawings]

FIG. 1 is a main part control configuration diagram of an industrial vehicle showing an embodiment of the present invention.

FIG. 2 is a block diagram of a control device for the industrial vehicle.

FIG. 3 is a block diagram of a control device for the industrial vehicle.

FIG. 4 is a characteristic diagram of vehicle speed and driving force of each transmission gear of the industrial vehicle.

FIG. 5 is a main part configuration diagram of a conventional industrial vehicle.

[Explanation of symbols]

Reference Signs List 1 engine 2 accelerator pedal 3 HST pump (hydrostatic pump) 4 main pump 5 charging pump 6 swash plate 7 HST motor (hydraulic drive motor) 9 servo cylinder 10 HST control valve 11 solenoid valve for inching 12 brake pedal 13 inching detection pressure Sensor 15 Transmission 16 Axle 17 Parking brake 18 Service brake 21 Travel speed detector (speed detection means) 31 Control device (control means) 32 Shift hold select switch (selection means) 33 Auto mission mode select switch (selection means) 34, 35 Solenoid valve for speed gear clutch 37 Transmission control valve

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) F16H 59:42 59:44 59:54 (72) Inventor Kazuya Ito 1-15 Kyomachibori, Nishi-ku, Osaka-shi, Osaka No. 10 Toyo Transport Machinery Co., Ltd. (72) Tomoyuki Kikuta Inventor 1-15-10, Kyomachibori, Nishi-ku, Osaka-shi, Osaka F-term inside Toyo Transporter Co., Ltd. GC44 GC46 GC64 HA15 KA01 LA01

Claims (3)

[Claims] 1. An industrial vehicle provided with a transmission, a speed detecting means for detecting a speed of the vehicle, a first speed fixed mode using only a first speed gear of the transmission, and a second speed gear of the transmission. Selection means for selecting a second-speed fixed mode using only the transmission, an economy mode in which automatic transmission is performed using high-speed gears of the transmission, and a power mode in which automatic transmission is performed using all gears of the transmission; An industrial vehicle, comprising: control means for controlling a shift of the transmission based on a speed of the vehicle detected by the speed detecting means and a mode selected by the selecting means. 2. In the economy mode, a second gear and a third gear of the transmission are used. When the economy mode is selected, the control means sets a shift point at which the second gear and the third gear are switched. ,
The industrial vehicle according to claim 1, wherein the speed is lower than the shift point in the power mode. 3. The control unit, when operating from the economy mode or the power mode, performs one operation by the selection unit.
When the fixed speed mode or the fixed second speed mode is selected,
3. The vehicle according to claim 1, wherein the speed of the vehicle is reduced to a speed range in which a first gear or a second gear is used, and thereafter, the vehicle shifts to a selected first gear fixed mode or second gear fixed mode. The industrial vehicle as described.