JPS616026A - Load control device in farm tractor - Google Patents

Abstract

PURPOSE:To aim at enhancing the efficiency of working, by detecting the rotational speed of an engine which varies in accordance with variations in load upon working, so that the speed of a vehicle is controlled in accordance with the rotational speed of the engine which is set to be in a high output power range. CONSTITUTION:When a load is exerted to a PTO and an axle to cause the rotational speed of an engine 10 to be lowered below a set value, a main speed change gear unit is automatically shifted by one stage to reduce the load. When the rotational speed of the engine 10 exceeds the set value after the load being decreased, the main speed change gear unit 10 is automatically reset to the original stage. This automatic speed control range is between a speed stage designated by a speed shift lever 4 and the first shift stage of the main speed change gear unit. If the engine speed is not returned into the set engine speed range even though it is in this automatic speed control range. A warning lamp is turned on for warning indication to suggest the operator to control the speed shift lever 4 or an accelerator lever 6.

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a traveling transmission device for agricultural tractors, which enables gear shifting without troubles such as engine stalling or overheating due to gear shifting mistakes. It is.

(B) Prior Art Conventionally, there have been devices that control the position of a working machine attached to the rear of an agricultural tractor in accordance with the rotational speed of the engine using draft control or slip rate control.

For example, JP-A-52-98105 and JP-A-55-8
This is similar to Publication No. 3619. However, in the conventional case, the transmission was an H8T type transmission, which was expensive. Additionally, the H8T type transmission had poor power transmission efficiency.

(c) Problems to be Solved by the Invention The purpose of the present invention is to improve the efficiency of heavy-load work by automatically controlling the load, and also to improve the efficiency of heavy-load work by automatically controlling the load. As soon as I am released, I work /
This makes it possible to prevent problems such as strikes and overheating from occurring.

In addition, as described above, in order to prevent accidents resulting in injury or death due to abnormal gear shifting even if electrical gear shifting means are provided, signals from electrical sensors are not used for gears other than gears used at a certain working speed. is configured so that no information is entered, giving priority to manual operation.

Furthermore, if there is a sub-transmission in addition to the speed range of the main transmission at the rear of the main transmission using the load control device of the present invention, the high-speed stage of this sub-transmission, etc. Since it is not used by anyone other than Zeng, it prevents operational errors.
In order to ensure the safety of the operator, automatic gear shifting is not possible at certain gears that are resistant to shifting.

Furthermore, in the transmission device with the negative 4TFI control device of the present invention, the gear position of the manual transmission means may be different from the gear position actually controlled by automatic control, so the system is configured so that both of these are displayed. It is something.

(→Means for Solving the Problems) The objects of the present invention are thus concluded.9 Next, the present invention will be explained in detail.

In tractors for personnel equipped with hydraulic clutch type transmissions that are equipped with manual transmission means and automatic transmission means such as electric methods,
A speed gear is set in advance by a manual gear shifter, and a gear shift to the designated gear gear is predetermined by an automatic gearchanger by determining signals from sensors such as engine speed and accelerator operation position. It is configured to change gears within a range of engine rotational speeds.

Again, hands! Only when the speed stage of the l1lI speed change means is at a specific speed stage, automatic speed change is possible based on an electric sensor signal.

Also, load control a! An auxiliary transmission is provided downstream of a main transmission with a transmission mechanism, and when the auxiliary transmission is located at the current speed stage, automatic gear shifting based on electrical sensor signals is disabled.

Further, a display device for displaying the speed stage position of the manual transmission means;
A display device that displays the actual gear position is also installed. .

(E) Embodiments and Functions The objects and structure of the present invention are as described above.21) Next, the embodiments and functions of the present invention will be explained based on the attached drawings.

FIG. 1 is a plan view of the agricultural tractor of the present invention. FIG. 2 is an enlarged plan view of the dash board surface of the agricultural tractor. Third
The figure is a drawing showing another embodiment of a manual gear position and an actual gear position display device. FIG. 4 is a block diagram of the load control device of the present invention. FIG. 5 is a diagram showing the configuration of a hydraulic clutch type main transmission equipped with a load control device. FIG. 6rl: Enlarged side sectional view of the hydraulic clutch type main KfA device. FIG. 7 is a table showing the operating state of the hydraulic clutch device shown in FIG. 6.

This @Akira detects the engine speed that changes due to load fluctuations during work, and controls the vehicle speed according to the engine speed set to maintain the engine's maximum output range, thereby controlling heavy loads. This aims to improve the efficiency of tractor work.

In other words, when the engine speed exceeds the set range due to an overload during work, the vehicle speed is shifted one step at a time in the direction of deceleration, and when the engine speed returns to above the set value, the vehicle speed is returned to the original speed step. By repeating these operations, the engine speed during work is maintained within the range described.

In FIG. 1, (c) is a seat, and (c) is a steering wheel. A display section (1) is provided on the dashboard (to) below the steering wheel (to), and a main f-speed shift device 1119 is provided at the center thereof.

The main gear shift is indicated by the manual gear shift means (19a).
) and a display device (19b) by automatic transmission means may be provided separately as shown in FIG. 2, but as shown in FIG.
Although there is actually one set of display devices as the main transmission shift display a, it may be a device that displays the gear shift position by the manual gear shift means by lighting continuously, and the gear shift position by the automatic gear shift means by blinking. It is. (2) is the engine tachometer. In addition, the speed change by the manual speed change means is actually performed by the speed change lever (4), and the position of this speed change lever (4) is known by six switches of the main F speed and the bar position filter/output switch UE, and the control is performed. Provide feedback to section (3).

In addition, signals are sent to the control section from the trough as shown in FIG. Sub-shift lever detection switch (151) of sub-shift lever (5), accelerator lever ~ (61 accelerator lever position aim output switch t131. Hydraulic lift lever detection switch of hydraulic lift lever (7) α-rotation brake pedal (8), etc. brake pedal position detection switch, engine speed sensor (9), solenoid valves that control each hydraulic clutch of the hydraulic clutch type main transmission (b), and automatic control "on" switch of the operating section (2). , "off" switch @, reset switch (c), etc.

When in the automatic control state, the automatic control indicator lamp (a) on the display section (1) lights up. (171us is a warning lamp.

The hydraulic clutch type main transmission will be explained with reference to FIGS. 5, 6, and 7.

First, in the side cross-sectional view of Fig. 6, the fourth forward speed is the hydraulic clutch device (B)
→ Single tooth C axis - → Shaft - → Gear group - Microwheel + 511 → Shaft (
(to) is driven.

The third forward speed is driven by the "contact" of the hydraulic clutch device (5) and (Y'') in the order of shaft → gear (sha) → gear - → shaft - gear ω → gear ei11- + gear (to) .

The second forward speed is set by the r-contact between the hydraulic clutch device (B) and the hydraulic clutch device (B).
→ Driven by gears (to).

The first forward speed is operated by a hydraulic clutch system (fitCA) and (3).
By "connection", the axis → Yoiguruma ■ → Gear - → Axis! 40 = axis (2)
- Driven from gear (to) → gear (to) → @ (to).

In neutral, hydraulic clutches (A), (B), and (C) are all rWrJ.
and ib are obtained.

The first movement in reverse is obtained when the hydraulic clutch device (6) and the body (body) are in "contact". @(2) → 1131 → Tooth Army-
It is driven in the following order: → gear lock → m (to) → gear lock → gear wire → pen (to).

The second movement in reverse is the "contact" of the hydraulic clutch device (6) and (a).
It is obtained by Shaft surface→Gear 143→Gear■→Gear−→
The shaft (2) → the shaft is driven from the wheel to the gear (511 → to the shaft).

Next, the hydraulic circuit shown in FIG. 5 will be explained.

The valley hydraulic clutches (A) (g) (b) (3) and (7) are provided with respective pressure sensors (to) (to) (to) (to) (to) (to) (to) (to), and the pressure oil reaches here. When each hydraulic clutch device is "engaged", a signal is outputted by the pressure sensor and displayed on the display device (19a) which displays the actual speed stage of the main transmission shift position display device. In the example shown in FIG. 3, it is displayed by blinking.

In addition, in the manual transmission means, when the gear shift lever (4) is operated to change the gear, the manual hydraulic control valve am@ is shifted to seven stages at once, changing from two reverse speeds to four forward speeds.

Then, when the automatic transmission means is turned on and negative FI control is performed, the electromagnetic control valve (to) switches the hydraulic clutch device (5) (B) and the reshaping clutch device) (7
) is switched.

The combination of switching (X) (Y) and switching (A) Φ) allows for 1st, 2nd, 3rd, and 4th speeds.

Next, let me explain the operation di.

Turn on the key switch of the agricultural tractor, turn on the power, and press the automatic control "on" switch (2) to start the engine Uω.
), the automatic control indicator lamp lights up, and the valley lever/pedal position detector confirms whether the tractor is in working condition. At this time, the corresponding display device IFI of the display section lights up to display the main shift lever shift position.

When the control starts, the load is applied to the PTO, axle, etc., and when the engine speed falls below the set value, the main shift is automatically shifted to 1.
The speed is reduced and the load is reduced.

When the load decreases and the engine speed exceeds the set upper limit, the main gear is automatically returned to the original speed. The next important thing to consider is the automatic control #shift range, which is between the gear specified by the gear lever (4) and the main shift. If the engine speed does not return to the set speed range even within this range, the warning lamp 071118+ lights up as a warning range, prompting the operator to operate the gear shift lever (4) or accelerator lever (6).

When a change occurs in the control operating conditions during control, the control is temporarily interrupted, control #1 is stopped and the engine is stopped, or control is continued, depending on the change number.

It is dangerous to leave the machine in a reserved state when it is not working, and it would be a waste of time to use it, so sensors in each part are used to determine when the machine is working and when it is not working.

Double-F, ;, :'w white The setting for both is the reception of the robe.

Then, automatic speeding is performed only when the conditions during work are satisfied. If the working status of each item changes to non-working, the system will act as shown in the response to the change in conditions, and when the condition returns to normal, it will become working again. .

Also, when the main & luck lever is at a specific gear stage, for example in the upper position (R
2) (R1) (G)) In the case of (1), the structure is such that the signal from the electrical sensor is not input so that the load control of the present invention is not performed.

In the case shown in FIG. 8, a sub-transmission device is disposed on the front side of the main transmission device equipped with the load control machine of the present invention, which further changes the speed after being changed by the main transmission device into a plurality of gears. When this sub-transmission is located at a specific gear stage, automatic gear shifting based on the electrical sensor signal of the main transmission is disabled. That is, in the embodiment shown in FIG. 8, when the f gear of the sub-transmission device enters the third gear, the automatic gear shift is stopped at 9 and the mode is changed to return to manual gear shift.

For example, when working in the field, load control can help! The system is designed to prevent the vehicle from suddenly shifting to a high gear that could cause an accident that could result in injury or death, such as when the vehicle finishes work and then shifts to high speed while remaining in the gill gear and driving on the road. The sub-drive device also has creep speed (C), ``2nd speed'', ``1st speed'', and ``N'', and in these cases, control is normal.

''; Below, Via Next, the control system for controlling the tractor load of the present invention can be classified as follows.

The mutual relationship between each control state is structured as shown in the mutual relationship table of each control state shown in FIG.

Moreover, FIG. 10 is a graph showing the set rotation speed of the engine. FIGS. 11 and 12 are diagrams of control states.

The setting range is set by setting upper and lower limits before and after the maximum position of the engine output curve. When the engine speed goes out of the set range during control, this time is set for a certain period of time (
If T1) or above does not exist, the controller will not judge that the engine speed has gone out of the set range. This (T1) is 2
It should be around seconds. Furthermore, if the control is interrupted during the control and automatic gear shifting is performed, the next control will not be started until more than (T2) time has elapsed after the automatic gear shifting has been performed. This (T2)
is approximately 3 seconds.

(f) Effects of the Invention Since the present invention is constructed as described above, it has the following effects.

First of all, you need to get used to the engine speed that changes in response to load fluctuations during work, and control the heavy load by controlling the vehicle speed according to the installed engine speed to achieve a high output range. It is possible to improve the efficiency of millet production.

Second, the operator does not have to worry about closely monitoring the rotation of the engine or the status of the work equipment, making the operation easier.

Third, automatic gear shifting is stopped in ranges where automatic wj control would be dangerous, such as in cylinder gear or reverse gear, so there is no risk of personal injury or the like.

[Brief explanation of drawings]

Figure g1 is a plan view of the agricultural tractor of the present invention. FIG. 2 is an enlarged view of the front surface of the agricultural tractor. Third
The figure is a drawing showing another embodiment of a manual Mh gear stage and an actual gear stage display device. FIG. 4 is a block diagram of the load control device of the present invention. FIG. 5 is a diagram showing the configuration of a hydraulic clutch type main transmission equipped with a load control device. FIG. 6 is an enlarged side sectional view of the hydraulic clutch type main transmission. FIG. 7 is a table showing the operating state of the hydraulic clutch device shown in FIG. 6. Figure 8 is a drawing showing the auxiliary transmission installed at the rear of the main gearbox. FIG. 9 is a drawing showing the correlation between each control state. FIG. 10 is a drawing showing the relationship between the engine output diagram and the set rotation speed. FIGS. 11 and 12 are diagrams showing actual control conditions. (b)...Hydraulic clutch type speed control (1)...Display part (4)...Shift lever (6)...Accelerator lever (9)...Engine speed sensor alarm ...Engine u9...gear stage display device Fig. 10 ↑ ';゛1x11 Fig. 12 I)- -> Figure private drawing amendment procedure amendment (voluntary) March 16, 1985 Date of 1982 Patent Application No. 124270 3 Relationship with the case of the person making the amendment Applicant Name Atsuo Yamaoka, representative of Yanmar Diesel Co., Ltd. 4, agent 5 Date of amendment order 6 Inventions increased by the amendment Number 7, subject of amendment 8 Details of the amendment (1) The table between the second line of the 14th page of the specification and the 14th line of page 14 will be amended as follows.

Claims (4)

[Claims] (1) In an agricultural tractor equipped with a hydraulic clutch type transmission that is equipped with both a manual transmission means and an automatic transmission means, a speed gear is determined in advance by the manual transmission means, and the gear shift to the specified gear is controlled based on the engine speed and the accelerator pedal. A load control mechanism for an agricultural tractor configured to shift gears within a predetermined engine speed range using automatic gear shifting means by determining signals from sensors such as operating positions. (2) The load control mechanism for an agricultural tractor as set forth in claim 1 is characterized in that automatic gear shifting is enabled by an electric sensor signal only when the gear gear of the manual gear shifting means is at a specific gear gear. load control mechanism for agricultural tractors. (3) In the load control mechanism according to claim 1, an auxiliary transmission device is provided at a subsequent stage to perform gear changes in multiple stages, and when the auxiliary transmission device is located at a specific speed stage, an electric sensor signal is sent. A load control mechanism for an agricultural tractor, characterized in that automatic gear shifting is impossible. (4) In the load control mechanism according to claim 1, a display device that displays the speed gear position of the manual transmission means;
A load control mechanism for an agricultural tractor, characterized in that a display device for displaying the actual gear shift stage position is also provided.