JPS5830403Y2 - Traction or pressing force detection device for mobile agricultural machinery - Google Patents

Description

[Detailed description of the invention] The invention detects the traction or pressing force acting on the ground work device, which is connected to the machine via the top link and lower link so that it can be raised and lowered, and based on the detected load. The present invention relates to a tractive force or pressing force detection device for a mobile agricultural machine, which is used when automatically controlling the elevation of the above-mentioned ground work equipment.

The technology disclosed in Japanese Utility Model Application Publication No. 50-68802 has already been used to detect the traction or pressing force acting on the ground work device and automatically control the elevation of the ground work device based on the detected load. Are known.

This conventional structure converts the traction or pressing force acting on the lower link into a swinging motion of the lifting link operated by the deflection of the mounting shaft of the lower link, and the spool of the valve of the cylinder for lifting the lift arm. is operated only while the lifting link continues to swing, that is, the valve operation time is increased or decreased by on/off control depending on whether or not the lower link mounting shaft is deflected. Since the structure is controlled by indirect load detection, it is difficult to accurately grasp the magnitude of the traction or suppression load itself, making it difficult to perform highly accurate control.

The present invention was developed in view of the above-mentioned circumstances, and its purpose is to sufficiently expand the amount of swinging displacement of the load detection arm that swings in response to traction or pressing force, thereby improving load detection accuracy. The purpose of this invention is to enable the entire device to be configured compactly.

The traction or pressing force detection device for the mobile agricultural machine of the present invention is as follows:
In a mobile agricultural machine in which a ground work device is connected to the machine frame of the machine via a top link and a lower link so that it can be raised and lowered,
One end of the arm disposed along the side of the machine frame is swingably attached to the machine frame via a fixed support shaft, and the lower link is attached to the arm near the fixed support shaft at this one end. The mounting on the machine side is configured so that the base end is pivotally attached via a swinging fulcrum shaft to magnify the tensile force or compressive force acting on the lower link and convert it into a swinging amount, and the swinging of the arm is A link mechanism that further expands the amount of displacement by a lever ratio is connected to the other end of the arm, and the rocking motion of the link mechanism and the final link of the link mechanism is converted into rotational motion, and the momentum is converted by a gear ratio. In addition to connecting the expanding gear mechanism, a mechanism is provided to extract the amount of rotation of the final gear of the gear mechanism as a load value to detect the tensile force or compressive force acting on the lower link. The mechanism is characterized in that at least the last link of the gear mechanism is configured to be positioned so as to overlap within the rotation range of the first stage gear when viewed in a direction perpendicular or perpendicular to the rotation plane of the first stage gear of the gear mechanism. .

In other words, the amount of rocking displacement of the load detection arm that swings in response to traction or pressing force is sufficiently expanded by the lever ratio of the link mechanism and the gear ratio of the gear mechanism, and the load is detected. Since it aims to improve accuracy, it is possible to directly detect the traction or suppression load itself as the rotation amount of the final gear, and the detected value can be accurately amplified by the amplification effect of the link mechanism and gear mechanism. It has now been possible to detect it.

Furthermore, since at least the last link of the link mechanism is placed in an overlapping position within the rotation range of the first stage gear of the gear mechanism, the amount of protrusion of the constituent members in the direction of the rotating surface of the first stage gear can be extremely small, and the link Even though the mechanism and gear mechanism are provided, the entire device can be constructed compactly.

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

Figure 1 shows a riding-type tiller, including a tractor (hereinafter referred to as this machine).

) 5, there is a plow 6, which is a ground work device that tills the soil as the aircraft advances, with one top link 7 and two plows arranged opposite each other in a letter G shape when viewed from above. A pair of left and right lift arms 10 are connected to be movable up and down via a lower link 8.8 and are driven to swing vertically around the horizontal axis at the rear of the machine 5 by a hydraulic cylinder 9.
10 and the lower links 8 and 8 pairs, respectively, are connected to the lift rond 1.
1.11, and thus the hydraulic cylinder 9
The plow 6 is driven up and down by the telescopic operation of the plow 6.

FIG. 2 shows plowing depth control of the plow 6, which is constructed as follows.

That is, the setting from the plowing depth dial 12 for setting the lower limit of the plow 6 and the detector 13 for detecting the lift arm angle.
The detection signal from the plow 6 is input to the first differential amplifier 14, and the difference signal from the first differential amplifier 14 is used to determine whether the plow 6 should be raised or lowered. At the same time, the difference signal from both comparators 15A and 15B is input to the ascending drive circuit 16A and descending drive circuit 16B of the electromagnetic valve 16 that controls the drive of the hydraulic cylinder 9. It is configured as much as possible.

In addition, the 8 pairs of rocking fulcrum shafts 17, 17 of the lower link 8°
The detected traction load value of the detection device 18, which magnifies and detects the traction force acting on the traction force, and the reference traction load value set by the draft dial 19 are input to the second differential amplifier 20. The difference signal from 20 is input to the first differential amplifier 14, and the plow 6 is controlled so that the detected value from the detector 13 and the detected tractive load value from the detecting device 18 are fed back. It is configured to automatically perform elevation control based on the detected traction load value while maintaining a proportional relationship.

In the figure, 21A and 21B are dead zone setting devices for ascending and descending.

The load detection device 18 is constructed as shown in FIGS. 3 to 7.

That is, the tensile force acting on the pair of lower links 8, 8 is applied to the fixed support shafts 22, 22, which are provided with the same name on the side of the transmission case 5A, which is the machine frame of the machine 5, and run along the left and right lateral directions. In order to expand the vertical swing, the lower link 8, 8 pairs of swing fulcrum shafts 17 are installed at the base end.
, 17 are fixedly fixed, and a pair of load detection arms 1, 17 extending forward along the side of the transmission case 5A are pivotally mounted to be vertically swingable. The spring holder fixed to the tip of is part 23
．． 23 and box-shaped spring receivers 25, 25 formed at both left and right ends of the fixing member 24 attached to the lower part of the transmission case 5A, a pair of load detection arms 1, 25 are inserted downwardly. Elastic biasing spring 26.26
At the same time, the load detection arms 1 and 1 pair are connected in the middle via a stay 27, and the distal end of one arm 1 of the pair of arms 1 is attached to the fixing member 24 side. The potentiometer 4 provided on the plate 28 is connected to the link mechanism 2 which further expands the amount of rocking displacement at the tips of the arms 1, 1 by the lever ratio, and the rocking of the final link 2B of this link mechanism 2. In addition to converting it into rotational motion,
The motor is moved through a gear mechanism 3 whose interlocking amount is expanded depending on the gear ratio, and the potentiometer 4 is configured to take out the amount of rotation of the final gear 3B of the gear mechanism 3 as a load value. ing.

The link mechanism 2 and gear mechanism 3 are constructed as follows.

That is, the mounting is performed on the plate 28, and the potentiometer 4 is mounted on the plate 28.
Of the two support shafts 29 and 30 provided at appropriate intervals on a vertical line passing through the axis of the rotation shaft 4A, two links of different lengths are attached to the rotation support shaft 29 located near the potentiometer 4. 2A and 2B are fixed with a phase angle of about 90 degrees, and the free ends of the two short first-stage links are pivoted to the end of the link 31 which is pivoted to the spring receiving member 23 of one of the load detection arms 1. connecting, thereby transmitting the swinging displacement amount of the tips of the load detection arms 1, 1 to the link 31, swinging the two links 2A, 2B having different lengths,
The swinging amount of the arm 1 is increased by the link mechanism 2 depending on the lever ratio between the two first-stage links and the final link 2B.

Further, on the other fixed support shaft 30, a fan-shaped first stage gear 3A that meshes with and interlocks with the final gear 3B attached to the rotary shaft 4A of the potentiometer 40 is rotatably pivoted. For installation, a pin 32 and a long hole 33 are provided between the base end and the free end of the final link 2B of the link mechanism 2 to convert the swinging motion of the final link 2B into the rotational motion of the first gear 3A. So, final link 2
The amount of rocking displacement of the roadside B is expanded by the lever ratio between the distance from the pin 32 to the support shaft 30 and the radius of the first gear 3A, and the rotational momentum of the first gear 3A is increased by the rotational momentum of the first gear 3A and the final gear. It is configured to be expanded by the gear ratio with 3B.

Further, the final link 2B of the link mechanism 2 is located in an overlapping position within the rotation range of the first stage gear 3A of the gear mechanism 3 when viewed in a direction perpendicular or perpendicular to the rotation plane of the first stage gear 3A. .

In the above embodiment, the swinging motion of the final link 2B is converted into the rotational motion of the first stage gear 3A via the pin 32 and the elongated hole 33, but as shown in FIG. The first gear portion 34 and the first stage gear 3A formed on the free end of the
The attachment may be converted into rotational motion via the second gear portion 35 provided at the base end.

[Brief explanation of drawings]

The drawings show an embodiment of the traction or pressing force detection device for a mobile agricultural machine according to the present invention, in which Fig. 1 is an overall side view of a riding type cultivator, Fig. 2 is a block diagram showing tillage control, and Fig. 3 is an essential part. Fig. 4 is an enlarged partially cutaway side view of the main part, Fig. 5 is an enlarged vertical sectional rear view of the main part, Fig. 6 is an enlarged partially cutaway rear view of the main part, FIG. 7 is an enlarged side view of the main part, and FIG. 8 is an enlarged side view of the main part showing another embodiment. 1...Load detection arm, 2...Link mechanism, 2B...Final link, 3...Gear mechanism, 3A...First stage gear , 3B...
Final gear, 4... Mechanism, 5... Machine,
5A...Machine frame, 6...Ground work equipment,
7...Top link, 8...Lower link, 17...Rotating fulcrum shaft, 22...Fixed shaft.

Claims (1)

[Scope of utility model registration request] In a mobile work machine in which a ground work device 6 is connected to a machine frame 5A of the machine 5 so as to be able to rise and fall via a top link 7 and a lower link 8, an arm 1 is arranged along the side of the machine frame 5A. One end side is swingably attached to the machine frame 5A via the fixed support shaft 22, and the lower link 8 is attached to the arm 1 portion near the fixed support shaft 22 at the base end. The lower link 8 is pivotally connected via the swing fulcrum shaft 17.
A link mechanism 2 and the other end of the arm 1 are configured to magnify the tensile force or compressive force acting on the arm 1 and convert it into a swinging amount, and further expand the swinging displacement amount of the arm 1 by a lever ratio. The link mechanism 2 is connected to a gear mechanism 3 that converts the swing of the final link 2B of the link mechanism 2 into rotational motion and expands the momentum by a gear ratio. A mechanism 4 for extracting the amount of rotation of the gear 3B as a load value is provided to detect the tensile force or compressive force acting on the lower link 8, and furthermore, at least the final link 2B of the link mechanism 2 is connected to the gear mechanism 3. Detection of traction or pressing force in a mobile agricultural machine, characterized in that the first stage gear 3A is configured to overlap within the rotation range of the first stage gear 3A when viewed in a direction perpendicular or perpendicular to the rotation plane of the first stage gear 3A. Device.