JPH03213752A - Engine speed detection structure - Google Patents

Abstract

PURPOSE:To maintain the relative position relation of an inspecting action piece and a sensor fixedly, by fitting the sensor to a tension arm supporting a belt tension pulley, and providing at one side end of the belt tension pulley a rotating speed inspecting operation portion confronting this sensor. CONSTITUTION:When an engine 4 is driven, a belt tension pulley 27 at a belt transmission mechanism 7 is driven rotatingly together with a transmission belt, and the rotation of an inspecting operation piece 29 provided at the tension pulley 27 is detected by means of a sensor 26. In addition, the tension pulley 27 and a tension arm 28 are integrally provided at all times, so the relative position relation of the inspecting operation piece 29 and the sensor 26 is always maintained fixedly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine rotation speed detection structure used in agricultural machinery such as a rice transplanter, and more specifically, the present invention relates to an engine rotation speed detection structure used in agricultural machinery such as a rice transplanter. The present invention relates to an engine rotation speed detection structure configured to transmit the engine rotation speed to an input shaft of a mission case via a non-contact sensor.

[Conventional technology]

In the above structure, conventionally, the rotational speed detection sensor is disposed near the output shaft of the engine, and the detection actuation piece that acts on this sensor is formed on the engine output shaft.

[Problem to be solved by the invention]

The rotation speed detection sensor is for inputting the measured value of the engine rotation speed into an electric control device for controlling the speed change of the traveling aircraft, for example, but as described above, it directly detects the rotation of the engine output shaft. When configured to do so, the output shaft vibrates slightly in the shaft radial direction as the engine is driven, whereas the detection sensor is installed in a fixed position at a non-rotating location, that is, on the aircraft frame side, so the distance between the two is fixed. There was a problem that the detection accuracy was lowered because the detection accuracy was not constant.

The present invention aims to eliminate the above-mentioned disadvantages through rational structural improvements.

[Means to solve the problem]

A characteristic configuration of the present invention is that in the engine rotation speed detection structure described at the beginning, the sensor is attached to a tension arm that supports the belt tension pulley in the belt transmission mechanism, and the sensor is attached to one end of the belt tension pulley. The main feature is that a detection actuator for detecting the rotational speed is provided.

[For production]

When the engine is driven, the belt tension pulley in the belt transmission mechanism is rotated together with the transmission belt.
The sensor detects rotation in a detection actuation piece provided on the tension pulley. Moreover, since the tension pulley and the tension arm are always provided integrally, the relative positional relationship between the detection actuation piece and the sensor is always maintained constant.

〔Effect of the invention〕

As a result, a constant relative positional relationship is always maintained between the detection actuating piece as the non-detection rotating portion and the sensor as the non-rotating fixed detection portion, improving detection accuracy. Moreover,
By effectively utilizing the structure of the tension pulley provided to apply tension to the transmission belt, this can be achieved with simple improvements without complicating the structure.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 5 shows a riding type rice transplanter according to the present invention. This rice transplanter has a link mechanism (
2), the seedling planting device (3) is connected to the seedling planting device (3) so as to be movable up and down.

As shown in FIG. 1, the traveling aircraft (1) is equipped with an engine (4) at the front of the aircraft,
The mission case (5) is installed at the rear of the engine (4).
) is configured to transmit the power from the engine output shaft (6) protruding sideways to the input shaft (8) of the mission case (5) via the belt transmission mechanism 7). It is configured to supply driving power to the wheels (9) and (10). A gear engagement type main transmission (not shown) is housed inside the mission case (5), and the main transmission lever (11) is configured to change the speed of the main transmission. A continuously variable transmission (12) is interposed in the transmission system between the transmission case (5) and the transmission case (5). To explain in detail, the engine side boot 1 bar 1 in the belt transmission mechanism (7)
3) and the transmission case side pulley (14) are each constructed as a split pulley type, and the distance between the respective pulleys is reversely changed by riding-up cam mechanisms (15) and (16), so that the speed can be changed steplessly. It has been done. The ride-up cam mechanisms (15) and (16) are configured to be driven via a rod (19) by an electric cylinder (18) provided on the side of the rear driver seat (17) installation area. .

Then, the gear shift lever (2) installed on the control panel (20)
1) Potentiometer (PMI) for setting the swing operation amount
The controller (22) drives the electric cylinder (18) based on the signal detected by the bell crank (23) from the connecting portion between the electric cylinder (18) and the rod (19). and rod (24)
Potentiometer (PM2) for feedback via
This potentiometer (
transmitting a detection signal of PM2) to the control device (22),
Potentiometer (PM) for setting the electric cylinder (18)
It is configured to stop the drive when the drive reaches the set amount according to I).

As shown in Fig. 4, in the high-speed side operating range of the operating lever (21), there is a contact type check for changing and adjusting the maximum speed setting position according to differences in working conditions such as soil conditions in the field. A member (25) is provided.

The rotational speed of the engine (4) is detected by a non-contact sensor (26), and the continuously variable speed control operation as described above is performed only when the engine rotational speed is in a predetermined high-speed driving state. In a stopped state or a low-speed driving state, the electric cylinder (18) is stopped from driving to prevent burnout due to overload.

The sensor is attached to a tension arm that supports a belt tension pulley in the belt transmission mechanism, and a detection actuator for detecting the rotational speed of the sensor is provided at one end of the belt tension pulley. Specifically, as shown in FIG. 2, the boss portion (28a) of the tension arm (28) is pivotally supported on a support shaft (30) protruding from the side of the transmission case (5), and the tension pulley (27) The tension arm (
28) is fixed. And the tension arm (2
An electromagnetic sensor (26) for detecting the number of revolutions as the ferromagnetic material approaches and separates is fixedly attached to the part facing the tension pulley (27) of 8), and the cylindrical part of the tension pulley (27) (27a) extends toward the arm side, and as shown in FIG.
29), (29) is formed in a protruding manner.

With this configuration, the detection actuation parts (29), (29) and the sensor (26) are connected regardless of the driving state of the engine (4).
) is always constant, so both (26
), (29) can be set to a small value, and the detection accuracy can be increased.

In addition, since the tension pulley (27) itself is cut out and processed, the surface adjacent to the sensor (26) has an arc shape, further increasing precision, and the structure can be simplified by sharing parts. It turns out.

[Another example]

Instead of having the above-mentioned protruding piece shape, the detection actuating part (29) may be formed by drilling holes as shown in FIG. 6.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of drawings]

The drawings show an embodiment of the engine rotation speed detection structure according to the present invention, FIG. 1 is a side view showing a speed change control system, FIG. 2 is a cutaway plan view of the main part, and FIG. 3 is a perspective view of the main part. FIG. 4 is a perspective view of the operating lever, FIG. 5 is an overall side view of the rice transplanter, and FIG. 6 is a perspective view of main parts of another embodiment. (4)...Engine, (5)...Mission case, (6)...Output shaft, (7)...
...Belt transmission mechanism, (8) ...Input shaft,
(26)...Sensor, (27)...Tension pulley, (28)...Tension arm, (29)...Detection actuation section.

Claims (1)

[Scope of Claims] The engine is configured to transmit power from the output shaft (6) of the engine (4) to the input shaft (8) of the mission case (5) via the belt transmission mechanism (7), and (4) An engine rotation speed detection structure configured to detect the rotation speed using a non-contact sensor (26), the tension arm supporting the belt tension pulley (27) in the belt transmission mechanism (7). The sensor (26) is attached to the belt tension pulley (27), and a detection operating part (29) for detecting the rotation speed of the sensor (26) is provided at one end of the belt tension pulley (27). structure.