JP2883007B2 - Transmission of construction vehicle - Google Patents

Abstract

PURPOSE:To perform a gear shift according to a selected gear shift pattern by selecting the gear shift pattern by a gear shift pattern selecting means and previously selecting the gear shift pattern according to the dimensions of a working area at a site by performing gear shift operation by a gear shift operation means. CONSTITUTION:A gear shift control device 7 is electrically connected to a gear shift lever 12 being a gear shift operating means and a display device 13 to display a selected gear shift pattern and a gear shift position and sets a desired gear shift position by means of a signal from the gear shift lever 12. The gear shift control device 7 is provided with a memory device 14 to store a plurality of gear shift patterns therein and electrically connected to a gear shift pattern selection switch 11. Arbitrary one of a plurality of gear shift patterns in the memory device 14 is selected by the gear shift pattern selection switch 11 and gear shift operation is executed in a gear shift pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission device for a construction vehicle such as a wheel loader, and more particularly to a construction device having a plurality of shift patterns and capable of selecting a shift pattern suitable for a site use situation. The present invention relates to a transmission for a vehicle.

[0002]

2. Description of the Related Art A construction vehicle such as a wheel loader (hereinafter simply referred to as a wheel loader) is used for transporting earth and sand. In recent years, a wheel loader of this type has been used similarly to a general passenger car. , In view of ease of driving operation,
Automatic transmissions are being adopted in place of manual transmissions. Since the automatic transmission does not require a shift operation, there is an advantage that an operator who frequently operates and works for a long time can reduce fatigue and can operate even if the operator is not skilled in the shift operation.

[0003] In the case of such a wheel loader or the like, the work area at the site where the wheel loader is used is significantly different. For example, from a site where the transport distance is several hundred meters, the transport distance is only about 10 mails. There are cases where the same vehicle is present at various sites, and the same vehicle is carried to various sites with completely different transport distances and used there. In addition, there is a case where it is used at a steep site where the climbing angle is 20 ° or more.

[0004] In the case of the conventional manual transmission, a human performs a gear shift operation.
Simply the number of shift positions to be used (for example, in a manual four-speed transmission, two stages from a first speed stage to a second speed stage are used, and four stages from a first speed stage to a fourth speed stage are used. However, the configuration itself of the transmission did not pose any particular problem because only the case was changed.

However, in the case of a conventional wheel loader or the like provided with the above automatic transmission, only one shift pattern is prepared for one vehicle, as in the case of a general passenger car. That is, in the first position, the first
The speed stage is fixedly formed, and in the second position, the first
From the gear stage to the second gear stage, the first position in the third position
From the first gear to the third gear, the first position is in the fourth position.
In the case of an automatic transmission configured to automatically shift according to the traveling state or the load state from the speed stage to the fourth speed stage, the use state is different,
In the transmission, for example, a first gear is fixedly formed in a first position, a second gear is fixedly formed in a second position, and a third gear is fixed in a third position. In the fourth position, the shift pattern cannot be easily changed so that the speed is automatically changed from the second speed to the fourth speed according to the traveling state or the load state.

[0006]

As a result, at a site having a work area of a general size and terrain, the advantages of the automatic transmission described above are exhibited, and despite the fact that the transmission is very easy to use, At a special site where the work area is significantly different, the shift pattern does not match the work area, so that the advantages of the automatic transmission may not be fully exhibited.

In such a case, it is also possible to increase the number of positions of the transmission so as to provide a number of shift positions suitable for work areas of various sizes, and to select and use these appropriately. However, when the position increases, the operation of the speed change operation means becomes complicated in proportion to the increase, and the transmission becomes difficult to handle by the operator.

It is also conceivable to prepare a shift control device having a different shift pattern for each work area and replace it each time. In this case, it is necessary to replace each time with a device suitable for the work area at each site. Therefore, it is very burdensome for a maker to prepare a shift control device of any kind of shift pattern, and it is also difficult for a user to prepare a shift control device of a new shift pattern every time the site is changed. This imposes an economic burden. Further, the operation of replacing the transmission control device is a large-scale operation that requires time and effort by a skilled service person.

[0009] In general, in a vehicle such as a passenger car or a construction vehicle, there is a transmission that can switch between two modes, a power mode and an economy mode, in accordance with a load state such as a climbing angle and a loaded load. However, in this case, it is possible to cope to some extent only by changing the reduction ratio univocally for input or output to a single shift pattern, but it is not possible to cope fundamentally. As this kind of prior art, there is JP-A-2-138563.

The present invention has been made in view of such a situation, and a transmission pattern of a construction vehicle in which a transmission pattern can be selected in advance in accordance with the size of a work area at a site and the like and a transmission can be performed according to the selected transmission pattern. The purpose is to provide.

[0011]

According to the present invention, there is provided a transmission for a construction vehicle according to the present invention. The transmission for a construction vehicle is constructed such that a desired shift position can be selected by the shift operation means. Storage means for storing a plurality of shift patterns having a series of shift positions selectable by the shift operation means, shift pattern selection means for selecting a desired shift pattern from the plurality of shift patterns, and selection by the shift operation means A shift control means for controlling a shift operation in accordance with a specific shift pattern selected and stored in the storage means, wherein a plurality of shift patterns stored in the storage means by the shift pattern selection means are provided. If you select a gear shifting pattern that is suitable for the on-site usage situation, Characterized in that it is configured to be changed by.

Further, in the transmission for a construction vehicle,
If one of the gear shift patterns includes a manual gear shift pattern, it is normally used as an automatic transmission, and can be used as a manual gear shift as needed.

[0013] In the transmission for a construction vehicle,
If a shift pattern rewriting means capable of arbitrarily rewriting the shift pattern is provided, and at least one of the shift patterns stored in the storage means is configured to be rewritable,
It is possible to obtain a shift pattern that better matches the situation at the site.

Further, in the transmission for a construction vehicle, the storage means may include an EEPROM (Electrically Erased).
By providing "able Programmable Read Only Memory", the speed change pattern can be freely rewritten in the EEPROM.

[0015]

According to the transmission of a construction vehicle according to the first aspect of the present invention, the shift pattern is selected by the shift pattern selecting means in accordance with the use condition such as the size of the work area at the site. Then, if a shift operation (setting of a shift position) is performed by the shift operation means, the shift control means performs the shift control in accordance with the selected shift pattern and the shift position selected among the selected shift patterns. In this case, if one of the shift patterns is provided with a manual shift pattern, it is possible to operate in the same manner as the manual transmission.

Accordingly, the operator of the construction vehicle (in some cases, a service person) simply selects a shift pattern from various shift patterns including a manual shift pattern in accordance with the work area of the site, and matches the site. A changed gearshift state can be obtained.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A transmission for a construction vehicle according to an embodiment of the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of a transmission for a construction vehicle and its periphery according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an engine constituted by an internal combustion engine, 2 denotes a torque converter constituted by a fluid coupling, 3 denotes a hydraulic pressure for selectively intermittently connecting a plurality of gears to form a gear train for power transmission. Transmission equipped with clutch 3A, 4
A is a differential device for transmitting power from the transmission 3 to the axle shaft 4B side, 4B is an axle shaft,
Reference numeral 5 denotes a brake disposed on the axle shaft 4B, and reference numeral 6 denotes wheels.

The output from the engine 1 is transmitted to a transmission 3 via a torque converter 2, and the transmission 3 shifts the output to a desired speed ratio to drive the differential device 4A and axle shaft 4B. And transmitted to the wheels 6 via the brakes 5 when necessary.
It is constituted so that braking may be applied.

As shown in FIG. 1, a solenoid valve 3B disposed on the transmission 3, which forms part of the transmission, is a shift control means which also forms part of the transmission. It is electrically connected to the control device 7, and controls ON / OFF of the solenoid valve 3B to supply or cut off the hydraulic oil from the hydraulic unit 3C to the hydraulic clutch 3A.

The transmission control device 7 is electrically connected to an engine rotation sensor 8 provided near the output shaft 1A of the engine 1 and a vehicle speed sensor 9 provided near the axle shaft 4B. , The engine speed and the vehicle speed are detected.

Further, the shift control device 7 is electrically connected to a shift lever 12 as a shift operation means and a display device 13 for displaying a selected shift pattern and shift position. Is set, and the set shift position or the shift pattern selected by the shift pattern selection switch 11 described below is displayed on the display device 13.

The speed change control device 7 has a storage device 14 in which a plurality of speed change patterns are stored, and is electrically connected to a speed change pattern selection switch 11. It is configured such that any one of a plurality of shift patterns in 14 can be selected and a shift operation can be performed with the selected shift pattern.

In this embodiment, as shown in FIGS. 4A to 4D, the storage device 14 stores four types of shift patterns (decision tables for determining the speed steps). ing.

That is, in the case of the speed change pattern shown in FIG. 4A, the "first speed position" is fixed at "speed position I", and the "first speed position" and "second speed position" at "speed position II". "Speed stage" is automatically shifted according to the engine speed and the vehicle speed.
The "third speed stage" is automatically shifted according to the engine speed and the vehicle speed.
The "fourth speed stage" is automatically shifted according to the engine speed and the vehicle speed. This shift pattern is a standard shift pattern and can be used in a narrow work area or a wide work area.

In the case of the shift pattern shown in FIG. 4B, the "first shift speed" is fixed at the "shift position I", and the "second shift speed" is fixed at the "shift position II". The "third speed stage" is fixed at "shift position III", and the "second speed stage" to "fourth speed stage" are automatically shifted at "shift position IV" according to the engine speed and the vehicle speed. Has become. And this shift pattern is
This is a shift pattern that mainly includes a manual operation and enables an automatic shift operation. Further, in the case of the shift pattern shown in FIG. 4C, the “first shift stage” is fixed at “shift position I”, the “second shift stage” is fixed at “shift position II”, and the “shift position” is set. In “III”, the “first speed stage” to “second speed stage” are automatically shifted according to the engine speed and the vehicle speed, and in “gear position IV”, “first speed stage” to “fourth speed stage” The speed is automatically changed according to the rotation speed and the vehicle speed. This shift pattern is a shift pattern suitable for a relatively narrow work area or a site where a climbing angle is large.

In the case of the shift pattern shown in FIG. 4D, the "first shift speed" is fixed at "shift position I", and the "second shift speed" is fixed at "shift position II". The "third speed stage" is fixed at "shift position III", and the "fourth speed stage" is fixed at "shift position IV". That is, the shift pattern is for a manual shift operation.

The storage device 14 stores the data shown in FIGS.
A decision table (logic table for determining control) for determining a speed stage corresponding to the shift pattern shown in (D) (shown as a decision table corresponding to FIGS. 4A, 4B, and 4C) 6, 7 and 8. These decision tables only describe the forward side and omit the description on the reverse side, and the expression method of the decision table conforms to JIS X0125. “Y” indicates that the condition is satisfied, “X” indicates execution, and a blank portion indicates irrelevance.

The storage device 14 stores a shift map shown in FIG. 5 so that an optimal speed stage can be obtained from the engine speed and the vehicle speed.

The transmission thus constructed is mounted on a construction vehicle and operates as follows.

That is, prior to the work, the operator first operates the above-mentioned shift pattern selection switch 11 by
A desired shift pattern is selected from the shift patterns of (A) to (D) according to the situation at the site and the like.

For example, if the shift pattern shown in FIG. 4A is selected, a decision table (see FIG. 6) for shifting according to the shift pattern shown in FIG.

Then, in this state, as shown in FIG.
The shift lever 12 is turned in either direction of the arrow X to select forward or reverse, and the shift lever 12 is turned in the direction of the arrow R to select a desired shift position.
For example, when the shift lever 12 is rotated rightward in FIG. 1 of arrow X to select “forward” and is rotated in the direction of arrow R to the position of “position III”, data relating to this shift position (“ Advance and Position II
I ”) is stored in the memory M2 of the storage device 14 as“ M2 = FI
II ".

Then, the vehicle is automatically shifted between the first speed stage to the third speed stage depending on the engine speed and the vehicle speed by the following control in the forward travel. That is,
With the operator operating the shift lever 12 as described above, the vehicle speed is 6 km / h and the engine speed is 150
If it is 0 rpm (see the point “A” in FIG. 5),
The shift control device 7 determines that the “second speed position” is optimal from the shift map of FIG. 5, and stores the data in the memory M3 of the storage device 14. That is, “M3 = F2” is stored in the memory M3 of the storage device 14.

In this case, the transmission control device 7 performs the operation based on the decision table shown in FIG. 6, that is, the sequence shown in the arrow A of FIG. 6 and having the two conditions of M2 = FIII and M3 = F2. (A column having a “Y” symbol at the corresponding position), and obtaining an output value in that case (a value of M1 having an “X” symbol of the column; M1 = F2),
The gear stage is determined as “second speed stage”, and this determination is temporarily stored as “M1 = F2” in the memory M1 of the storage device 14, and based on the contents of this memory M1, the solenoid valve 3B By transmitting a control signal, the hydraulic clutch 3C is operated so that a gear train of “second forward speed stage” is formed.

As a result, the vehicle is shifted to the second forward speed and travels.

Further, while running under the above conditions, the engine speed becomes 2000 rpm and the vehicle speed becomes 12
When the speed is increased to km / h (see the point “A” in FIG. 5), the shift control device 7 determines that the “third speed stage” is optimal from the shift map in FIG. It is stored in the memory M3 of the device 14. That is, “M3 = F3” is stored in the memory M3 of the storage device 14.

In this case, the transmission control device 7 uses the same method as described above based on the decision table shown in FIG.
The gear position is determined as “third speed position” (see the column of arrow B in FIG. 6), and this determination is stored in the memory M1 of the storage device 14 as “M1 =
F3 "and the memory M1
The control signal is sent to the solenoid valve 3B on the basis of the contents of the above, so that the "forward second speed stage" to the "forward third speed stage"
The hydraulic clutch 3C is operated so as to form the gear train of FIG. As a result, the vehicle is automatically shifted (shifted up) from the second forward speed to the third forward speed and travels.

On the other hand, the vehicle speed is reduced to 9 km / h in a state where the engine speed is 1500 rpm by slightly releasing the accelerator pedal to reduce the accelerator opening (“C” in FIG. 5). Point) and
The shift control device 7 determines that the “second speed position” is optimal from the shift map of FIG. 5, and stores the data in the memory M3 of the storage device 14. That is, “M3 = F2” is stored in the memory M3 of the storage device 14.

In this case, the transmission control device 7 uses the same method as described above based on the decision table shown in FIG.
The gear position is determined as “second speed position” (see the column of arrow A in FIG. 6), and this determination is stored in the memory M1 of the storage device 14 as “M1 =
F2 "and the memory M1
The control signal is sent to the solenoid valve 3B on the basis of the content of (3) to change from "the third forward speed stage" to "the second forward speed stage".
The hydraulic clutch 3C is operated so as to form the gear train of FIG. As a result, the vehicle is automatically shifted (shifted down) from the third forward speed to the second forward speed and travels.

Further, when the engine speed is 1800 rpm
When the vehicle speed becomes 4 km / h (see point “d” in FIG. 5), the shift control device 7 determines from the shift map in FIG. 5 that “first speed stage” is optimal. Judge and store “M3 = F1” in the memory M3 of the storage device 14. In this case, the shift control device 7 determines the shift speed as “first speed” based on the decision table shown in FIG. 6 in the same manner as described above (see the column of arrow C in FIG. 6), and determines this. Is temporarily stored in the memory M1 of the storage device 14 as “M1 = F1”, and based on the contents of the memory M1, a control signal is sent to the solenoid valve 3B to change the “forward second speed stage” to “forward”. The hydraulic clutch 3C is operated so that the gear train of the "first speed stage" is formed. As a result, the vehicle is automatically shifted to the first forward speed (downshift).
Being driven.

When the engine speed has increased to 2200 rpm and the vehicle speed has increased to 20 km / h (see the point "o" in FIG. 5), the shift control device 7 performs the shift operation in FIG. From the map, it is determined that “fourth speed stage” is optimal, and “M3 = F4” is stored in the memory M3 of the storage device 14. However, in this case, the transmission control device 7 searches for a column that satisfies the conditions of “M2 = FIII” and “M3 = F4” shown in the arrow D of FIG. 6 based on the decision table shown in FIG. In this case, the output value “M1 = F
By obtaining "3", the shift stage is determined to be "third speed stage", so that the shift to the fourth speed stage is not performed and the third speed stage is maintained. As described above, by setting the decision table as shown by the rows of arrows A, B, C, and D in FIG. 6, the shift range at the shift position III is set to the first to third speed stages. Can be.

It should be noted that a simplified block diagram showing the signal flow of the above-described series of control processes and the flow of the processing signals is as follows.
As shown in FIG. FIG. 3 shows a specific configuration of the transmission control device 7.

Similarly, in the case of reverse travel, automatic gear shifting is performed so that the optimal speed stage is automatically selected according to the engine speed and the vehicle speed. Also, the shift lever 1
2 at another automatic shift position (for example, "position IV" or "position I
I)), the optimum speed stage is automatically selected within the range of FIG. 4A according to the engine speed and the vehicle speed, and only one speed stage is formed. When a gear position (for example, position I in this gear shift pattern) is set, a gear train of the set gear position (first gear position) is fixedly formed in the transmission, and the gear position is determined by the gear position. The speed is changed so as to travel.

When the operator selects the shift pattern shown in FIG. 4B by the shift pattern selection switch 11, the shift is performed from the storage device 14 according to the shift pattern shown in FIG. The decision table is read.

In this case, the shift is performed using the shift map shown in FIG. 5 and the decision table shown in FIG. 7 instead of FIG. 6 in the same manner as in the above embodiment. That is, in this case, when the shift position of the shift lever is “position I” to “position III”, one shift speed is fixedly formed, and at “position IV”, “second speed” to “second speed”. Automatic gear shifting is performed between "fourth gear".

When the operator selects the shift pattern shown in FIG. 4C by the shift pattern selection switch 11, the memory shown in FIG. 8 for shifting from the storage device 14 in accordance with the shift pattern shown in FIG. The table is read.

In the same manner as described above, in this case, when the shift position of the shift lever is "position I", the first gear is fixedly formed, and when the shift position is "position II", the second gear is fixed. Formed in "Position III"
, An automatic shift is performed between the first speed stage and the second speed stage, and an automatic shift is performed between the first speed stage and the fourth speed stage at “position IV”.

When the operator selects the shift pattern shown in FIG. 4D by the shift pattern selection switch 11, the shift is performed from the storage device 14 according to the shift pattern shown in FIG. The decision table is read.

In this case, the decision table shown in FIG. 9 is used. That is, in this case, the shift position of the shift lever is changed from "position I" to "position I".
In "V", one shift stage is fixedly formed between "first speed stage" to "fourth speed stage". That is, in this case, the shift lever 12 is configured such that the “first speed stage” is “position I”, the “second speed stage” is “position II”,
In "Position III", "3rd speed stage" is replaced by "Position I
The "fourth speed stage" is fixedly formed by "V", and the transmission functions in the same manner as the manual transmission.

By the way, instead of the above-described embodiment, at least one of the shift patterns can be rewritten by using rewriting means (for example, a keyboard) 15 (see FIG. 1) to change the contents of the shift speed corresponding to each position. The contents may be configured so that the operator or service person can freely set the contents according to the use state (site conditions or operator qualities). For example, when any one of the shift patterns shown in FIGS.
Automatic speed change between "speed stage" and "second speed stage",
"Position II" can be automatically shifted between "1st speed stage" to "3rd speed stage", and "Position III" can be automatically shifted between "1st speed stage" to "4th speed stage" The shift position may be rewritten so that the "position IV" can be set to be automatically shiftable between "2nd speed stage" to "4th speed stage". In this case, the shift position which complicates selection is changed. Without increasing the number of transmissions, it is possible to form a transmission that is optimal for the situation at the site or the qualities of the operator. A shift pattern that allows the contents of such shift speeds to be freely rewritten is E
It is preferable that the memory be stored in an EPROM (rewritable read-only memory) such as an EPROM.

In the above embodiment, four shift patterns are provided. However, it goes without saying that the number of shift patterns may be further increased or decreased.

[0054]

According to the transmission for a construction vehicle according to the present invention, a shift pattern can be easily selected in advance in accordance with the size of the work area at the site, and the shift can be performed according to the selected shift pattern. In operation, it is possible to obtain an optimal transmission for the site.

Therefore, it is possible for a manufacturer to provide a construction vehicle equipped with a very versatile transmission having a large degree of freedom in the transmission pattern, and thus to mass-produce the same transmission including a manual transmission. The cost does not increase so much as the function is improved.

For the user, the workability of the construction vehicle is greatly increased, and the setting of the optimal shift pattern can be greatly simplified by the shift pattern setting means.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a transmission of a construction vehicle and a periphery thereof according to an embodiment of the present invention.

FIG. 2 is a simplified block diagram showing a signal flow of a series of control processes and a flow of processing signals in the transmission shown in FIG. 1;

FIG. 3 is a block diagram showing a detailed configuration of a shift control device shown in FIG.

FIGS. 4A to 4D are diagrams showing the contents of each shift position of four shift patterns stored in the storage device of FIG. 1;

FIG. 5 is a diagram showing a shift map stored in the storage device shown in FIG. 1;

FIG. 6 is a diagram showing contents of a decision table of a shift pattern of FIG. 4A stored in the storage device shown in FIG. 1 and used when determining a speed stage.

7 is a diagram showing the contents of a decision table of the shift pattern of FIG. 4B stored in the storage device shown in FIG. 1 and used when determining a speed stage.

8 is a diagram showing contents of a decision table of a shift pattern of FIG. 4C which is stored in the storage device shown in FIG. 1 and used when determining a speed stage.

9 is a diagram showing the contents of a decision table of the shift pattern of FIG. 4D stored in the storage device shown in FIG. 1 and used when determining a speed stage.

[Explanation of symbols]

7 shift control device (shift control means) 11 shift pattern selection switch (shift pattern selection means) 12 shift gear (shift operation means) 14 storage device (storage device)

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Claims (4)

(57) [Claims] 1. A transmission apparatus for a construction vehicle, wherein a desired shift position can be selected by a shift operation means, wherein a plurality of shift patterns having a series of shift positions selectable by the shift operation means during traveling are stored. A shift means for selecting a desired shift pattern from among a plurality of shift patterns; and a shift operation executed in accordance with the selected specific shift pattern stored in the storage means by selection by the shift operating means. And a shift control means for controlling a shift pattern selected from among the plurality of shift patterns stored in the storage means by the shift pattern selecting means. The construction vehicle is characterized in that it can be shifted by Speed devices. 2. The transmission for a construction vehicle according to claim 1, wherein one of the shift patterns includes a manual shift pattern. 3. The apparatus according to claim 1, further comprising a shift pattern rewriting means capable of arbitrarily rewriting the shift pattern, wherein at least one of the shift patterns stored in the storage means is configured to be rewritable. 3. The transmission of a construction vehicle according to claim 1. 4. The transmission device for a construction vehicle according to claim 3, wherein said storage means includes an EEPROM, and said shift pattern is freely rewritable in said EEPROM.