JPH066005B2 - Agricultural depth control device for agricultural tractors - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a tillage depth control device for an agricultural tractor, and more particularly to a device configured to mechanically control both a rotary tiller and a plow.

[Conventional technology]

As a device constructed as described above, there has been heretofore been used as a conventional device.
There is one disclosed in Japanese Patent Publication No. 157807, and in this conventional example, when a rotary tiller is installed, it is automatically controlled based on the working depth, and when a plow is installed, it is automatically controlled based on the traction load. In each case,
Hydraulically configured to mechanically operate the valve in the housing.

[Problems to be Solved by the Invention]

In this conventional example, when a rotary cultivator is installed, and in each case when a plow is installed, a single operation system mechanically configured to operate a valve in the hydraulic housing is also used. It has various aspects.

Considering the respective work forms, there are the following inconveniences when performing the work of each of the rotary work and the plow work by a control system having a common mechanical linkage.

In other words, in plow work, the plowing depth is controlled based on the towing load having a substantially proportional characteristic that occurs during towing, whereas in rotary work, changes in the plowing depth of the rotary tiller are controlled with non-proportional characteristics. This is because the control of the plowing depth is performed based on the swing amount of the rear cover, which causes an error in the control in the control system having the mechanical linkage.

In order to eliminate this inconvenience, in the above-mentioned conventional example, control is not performed based on the swing amount of the rear cover, but proportional to the vertical operation amount of the rod linked to the rear end of the rear cover. It is configured to determine the working depth by characteristics.

However, since this rod has a large amount of vertical movement, it requires a control system that operates greatly in order to absorb this movement, and since the distance from the upper end of this rod to the valve is relatively large, a long wire is required. There is room for improvement due to the inconvenience required.

The object of the first invention is to suppress the increase in size of the control system,
The point is to configure a mechanical control system that accurately controls the plowing depth based on the swing amount of the rear cover and the plowing depth of the plow based on the traction load.

In addition to the object of the first invention, an object of the second invention is to make this control system easy to handle.

[Means for Solving the Problems]

A feature of the first invention is that a rotary tiller is provided with a mechanism that mechanically links a top link bracket that can swing back and forth and an operating lever of a lift arm lifting draft control valve, and that is vertically linked by a lift arm. Is provided with linking means for transmitting the swinging operation of the swing-type rear cover to the operating lever of the draft control valve, and the linking means is swingably operated in conjunction with the swinging operation of the rear cover. An arm is provided, and the smaller the ratio of the vertical movement amount of the rear end of the cover to the swing amount of the rear cover is, the smaller the ratio of the movement of the rear lever to the member for transmitting the operating force to the operating lever becomes. The operation of the arm with respect to the member for transmitting the operating force to the operating lever is made so as to proportionally reduce the operating amount of the operating lever with respect to the swing amount. Position, direction approaching the pivot axis of the arm with the swinging of the arm or,
A change rate changing mechanism for displacing in the direction of separating is provided. Further, the feature of the second invention is that the top link placket which can be rocked back and forth and the operating lever of the lift arm lifting draft control valve are mechanical. And a linking means for transmitting a swinging operation of the swinging type rear cover of the rotary tiller, which is vertically movable by a lift arm, to a working lever of the draft control valve. The means is provided with an arm that is rockably operated in conjunction with the rocking operation of the rear cover, and the rocking of the rear cover is provided at a location where the arm and a member that transmits an operating force to the operating lever are linked to each other. As the ratio of the amount of vertical movement of the rear end of the cover to the amount of movement decreases, the operating amount of the operating lever decreases proportionally to the swinging amount of the rear cover. As described above, the action position of the arm with respect to the member for transmitting the operation force to the actuating lever is displaced in a direction toward or away from the swing axis of the arm with the swing of the arm. A change rate changing mechanism is provided, and this mechanism is linked to the traction load adjusting lever of the draft control valve. The respective actions and effects are as follows.

[Operation of First Invention] That is, when the above-described linkage is performed, the plow work and the rotary work can be performed by the mechanical linkage type control system by using only one of the mechanisms as an alternative. Since the change rate changing mechanism is provided, the swing-type arm interposed between the rear cover and the operation lever and the arm are interposed between the rear cover and the operation lever during the rotary work regardless of the mechanical linkage. The contact position with the contact member is displaced in a direction toward or away from the swing axis of the arm as the arm swings, and as a result, the cover end with respect to the swing amount of the rear cover is moved. As the ratio of the amount of vertical movement of the rotary cover decreases, it is converted into a characteristic that reduces the amount of operation of the operating lever with respect to the amount of movement of the rear cover. In the draft Control valve can be operated, and with this configuration,
Unlike the conventional example, it is not necessary to absorb a large working stroke, and the wire etc. can be shorter than the conventional example.

[Effect of the first invention] Therefore, a control system for accurately controlling the plowing depth of the plow based on the swing amount of the rear cover and the plowing depth of the plow based on the traction load while suppressing an increase in the size of the control system is a mechanical system. It was constructed in a small size by using a dynamic link.

[Operation of Second Invention] That is, when the above-described linkage is performed, the plow work and the rotary work can be performed by the mechanical linkage type control system by using only one of the mechanisms alternatively, and the linkage mechanism can be used. Since the change rate changing mechanism is provided therein, a swing-type arm interposed between the rear cover and the operation lever at the time of rotary work, regardless of the mechanical linkage, The contact position with the member contacting the arm is displaced toward or away from the swing axis of the arm as the arm swings, and as a result, the swing amount of the rear cover is changed. As the ratio of the vertical movement amount of the cover end becomes smaller, the characteristic is converted into a characteristic that reduces the operation amount of the operating lever with respect to the swing amount of the rear cover, which is proportional to the change in the working depth of the rotary tiller. In operation amount The draft control valve can be operated, and the change characteristic of the operation amount of the operating lever with respect to the swing amount of the rear cover can be adjusted appropriately according to the control target level of the rear cover by operating the traction load adjusting lever, that is, the target working depth. Can be corrected.

[Effects of Second Invention] Therefore, in addition to the first invention, a control device having high operability can be configured.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 5, a steering wheel (2) and a boarding section (A) consisting of a seat (3) are provided on the vehicle body running on the front steering wheel (not shown) and the rear propulsion wheel (1), Hydraulic cylinders at the rear of the car body (4)
A pair of left and right lift arms (5) that move up and down with the lift arms (5) are connected through a lift rod (6), and a pair of left and right lower links pivotally supported at the rear end of the vehicle body.
(7) A plow (8) is attached to the rear end of the agricultural tractor.

In the tractor, when performing plow (8) plow work in the field, when the pulling load of the plow (8) becomes a certain level or more, the plow (8) is raised to reduce the pulling load, and
It is equipped with a mechanical linkage that lowers the raised plow (8) when the towing load decreases. To explain, as shown in FIG. 3, FIG. 3, and FIG. 4, the plow (8) is pivotally supported about the left and right axial center (P) with respect to the lower link (7).
The plow (8) is provided with a support arm (8a) facing upward. A top link bracket (10) is provided at the rear end of the tractor body via a torsion bar (9) so as to elastically swing back and forth only by an extremely large force, and the bracket (10) and the arm (8a) are connected to each other. Are connected via a top link (11).

The lift arm (5) is moved up and down by operating the operating lever (12) of the draft control valve (V) with respect to the hydraulic cylinder (4), and the operating lever (12) and the bracket (10) are (10) a cantilevered plate member (13), a pin (14) protruding from this member, a plate (15) having a long hole (15a) through which this pin (14) is inserted, and They are connected via a rod (16). When the pulling load of the plow (8) exceeds the set value while working with the plow (8), that is,
When the plow (8) approaches a hard field scene, around the axis (P), the plow (8) swings in the direction in which the lower end is pulled rearward, and by this swing, the arm (8a), Top link
The bracket (10) is swung via (11), and the operating lever of the valve (V) is moved through the plate member (13), the pin (14), etc.
Coordination is made to operate (12) in the upward direction of the lift arm (5).

In addition, the setting of the tow load of the plow (8) is performed by
This is done by operating the operation lever (17) provided on (A). That is, a link mechanism (not shown) is installed inside the case of the valve (V), and the swinging operation force of the actuating lever (12) causes the spool (not shown) in the valve to pass through the link mechanism. ),
In addition, this link mechanism changes the linkage by operating the traction load adjusting lever (18) provided outside the valve case, and the operating force of the operating lever (12) causes the spool in the valve to start operating. That is, the operation start end can be changed.

The lever (18) and the operating lever (17) are connected to the rod (1
The traction load is adjusted by changing the operation start end of the operating lever (12) with respect to the spool by operating the operating lever (17).

As shown in FIG. 6, in the tractor, the plow (8)
In place of this, when the rotary tiller (20) is provided at the rear of the vehicle body to perform plowing work, the draft control valve (V) is used to automatically keep the tilling depth of the rotary tiller (20) constant. It is also equipped with a mechanical linkage mechanism. In other words, the rotary tiller (20) can be driven up and down by a hydraulic cylinder (4) at the rear of the vehicle body via a pair of left and right lower links (7) and a top link (11) in substantially the same manner as the plow (8) described above. The rear cover (20a) of this rotary cultivator is pivotally supported on the main body of the device so as to be swingable around the left and right axis (Q), and further attached downward by a constant force by a spring (21). It is energized.

In addition, the top link bracket is used during rotary tillage work.
The front end of the top ring (11) is fixed to a support boss (22) provided at the rear end of the vehicle body so that the (10) does not swing.
3) Connected to the rear end.

As shown in FIGS. 1 and 2, the plate (15) having the elongated hole (15a) through which the pin (14) is inserted is further provided with another contact pin (24). Further, on the vehicle body side, another arm (26) is provided at the end of the arm (25) swingable around the axis (R) so as to be swingable around another axis (S). Arm (26)
Is provided at a position at which the contact pin (24) can be pressed from the rear, that is, at a position at which the contact pin (24) can be pressed from the direction in which the operating lever (12) is operated in the upward direction of the lift arm. .

A stay (27) bolted to each of the bracket (10) and the support plate (23) is provided behind the two arms (25) and (26), and the latter arm (26) is rocked. A member protruding from the lower end of the pivot boss (26a) of the arm (26) to move
A spring (28) is provided in a biased state between the lower end of (26b) and the stay (27), and further, a pin (29) is provided on the member (26b), and this pin (29) is inserted. A connecting member (30) having a long hole (30a) is attached, and at the rear end of the connecting member (30),
A push-pull wire (31) is connected to which the upward swing of the rear cover (20a) is converted into a tensile force and transmitted.

Then, during the rotary tillage work, when the rotary tiller (20) descends, the rear cover (20a) relatively swings upward,
With the pulling operation of the wire (31), the elongated hole (30a) is displaced rearward, and the arm (28) is displaced by the displacement amount of the elongated hole (30a).
The spring (28) is operated by its urging force to press the pin (24) to operate the operating lever (12) in the lift arm rising direction.

Also, the arm (25) is arranged to swing the former arm (25).
The member (25a) protruding from the rod and the adjusting lever (18) are
The change rate changing mechanism (B) is configured by being connected via (32), the operating lever (17) can be operated to set the working depth of the rotary tilling work, and the rear cover (20a) can be rocked. By adjusting the relative relationship between the amount of movement and the operating lever (12), it is possible to correct the error in the amount of vertical displacement. In other words, the operation lever (17) can be set to a deep ground work depth by operating in the direction indicated by (D) in the figure, and can be set shallow by operating in the direction indicated by (U) in the figure. Is configured. The change rate changing mechanism (B) configured as described above, as shown in FIG. 2, has a wire (31) for transmitting an operating force from the rear cover (20a) of the rotary tiller (20) in this configuration. Has a relatively small operating stalk, and when the rear cover (20a) swings, the contact pin (24) as a member that is operated by contacting the upper end of the arm (26) moves in the radial direction of the arm (26). As the arm ratio changes during operation, the arm ratio changes during operation, resulting in a non-proportional operation, and the operation of the wire (31) is associated with the working depth of the rotary tiller (20) in a non-proportional relationship. It cancels out and it changes to the operation which becomes a proportional relationship.

Incidentally, the long hole (15a) formed in the plate (15) is such that the operation of the plate (15) during the rotary cultivating work is performed by the plate member (13).
In addition, the long hole (30a) formed in the connecting member (30) causes the rear cover (20a) to be greatly swung by the ridge when the tractor ridge is crossed and the wire (31) In order not to damage the linkage mechanism when the stroke in the pulling direction becomes large, etc., the lengths are set to appropriate values.

Further, by operating the swing end of the operation lever (17) in the direction indicated by (D) in the figure, the rotary tiller (20) or the plow
It is configured so that (8) can be greatly forcibly raised.

[Another embodiment]

In this embodiment, the arm, the rod and the like are used to form the mechanical linkage, but other than these, the link, the cam, the gear and the like may be used together.

[Brief description of drawings]

The drawings show an embodiment of an agricultural tractor tillage depth control device according to the present invention. FIG. 1 is a perspective view of the linkage when the rotary tiller is automatically controlled, and FIG. 2 is a partially enlarged view of the linkage of the automatic tillage depth control. Fig. 3 is a perspective view of the linkage when the plow is draft-controlled, and Fig. 4 is a partially enlarged view of the linkage of the draft control.
FIG. 5 is a side view of the rear part of the tractor with the plow attached, and FIG.
The figure is a side view of a tractor to which a rotary tiller is attached. (5) …… lift arm, (10) …… top link bracket, (12) …… actuating lever, (18) …… traction load adjusting lever, (20) …… rotary tiller, (20a) …… rear part Cover, (26) …… arm, (B) …… change rate change mechanism, (S) ……
Swing shaft core, (V) …… Draft control valve.

Claims (2)

[Claims] [Claim 1] A top link bracket (1
0) and the operating lever (12) of the draft control valve (V) for lifting the lift arm are mechanically linked to each other, and the rotary tiller (20) of the rotary tiller (20) connected by the lift arm (5) so as to be liftable and lowerable. The rocking operation of the rocking type rear cover (20a) is carried out by operating the draft control valve (V).
2) is provided with a linking means, and the linking means is provided with an arm (26) which is rockably operated in conjunction with the rocking operation of the rear cover (20a). ) And the member for transmitting the operating force to the actuating lever (12), the rear cover (20a)
As the ratio of the amount of vertical movement of the rear end of the cover to the amount of swing of the rear cover (20a) decreases, the operating amount of the operating lever (12) relative to the amount of swing of the rear cover (20a) is proportionally reduced.
The action position of the arm (26) with respect to the member for transmitting the operating force to the actuating lever (12) approaches the swing axis (S) of the arm (26) as the arm (26) swings. A tilling depth control device for an agricultural tractor, which is provided with a change rate changing mechanism (B) for displacing it in a moving direction or in a separating direction. 2. A top link placket (1) which can be rocked back and forth.
0) and the operating lever (12) of the draft control valve (V) for lifting the lift arm are mechanically linked to each other, and the rotary tiller (20) of the rotary tiller (20) connected by the lift arm (5) so as to be liftable and lowerable. The rocking operation of the rocking type rear cover (20a) is performed by the operation lever (12) of the draft control valve (V).
And an arm (26) that is rockably operated in conjunction with the rocking operation of the rear cover (20a), and the arm (26) is connected to the arm (26). The rear cover (20a) is provided at a position where the operation lever (12) is linked to a member that transmits an operation force.
As the ratio of the amount of vertical movement of the rear end of the cover with respect to the swing amount of the rear cover (20a) decreases, the operation amount of the operating lever (12) relative to the swing amount of the rear cover (20a) decreases proportionally.
The action position of the arm (26) with respect to the member for transmitting the operating force to the actuating lever (12) approaches the swing axis (S) of the arm (26) as the arm (26) swings. A change rate changing mechanism (B) that displaces in the direction of moving or separating is provided, and this mechanism (B) is further linked to the traction load adjusting lever (18) of the draft control valve (V). Plowing depth control device.