JPS61132101A - Before and behind posture control apparatus of earth workingmachine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a longitudinal attitude control device for a ground work machine such as a rotary or plow connected to a tractor.
The top link can be shortened or extended to control the forward and backward inclination of the ground working machine when hoisting the working part of the ground working machine while it is still rotating, or to improve the flying performance and launching performance during plowing work. In the longitudinal attitude control device configured to check and perform the extension and contraction operation of the top link so that the rotation of the universal joint shaft for power transmission between the tractor and the ground work equipment is performed safely during each operation,
This paper proposes a control device that is devised so that the top link can be expanded and contracted in a precise manner.

Conventional technology In order to ensure sufficient lifting height or to improve plowing performance, the length of the top link is controlled to extend or contract by manual or automatic operation, and the posture of the ground work equipment in the longitudinal direction relative to the tractor is controlled. A control device for lifting and lowering a working machine is known as Japanese Unexamined Patent Publication No. 14710/1983.

The working part of the ground work machine is driven by a universal joint shaft that connects the PTO shaft of the tractor and the input shaft of the ground work machine, but the bending angle of the joint part of the universal joint shaft with respect to the PTO shaft or the input shaft. will vary depending on the ^Δ top height and the above-mentioned longitudinal orientation, and if this becomes too large, troubles such as damage to the joint pin will rapidly increase.
When lifting or lowering the ground work machine or extending or retracting the top link, it must be ensured that the bending angle of the joint is within a safe range and does not become excessive. However, since conventionally known control devices do not have such confirmation means, there is a risk that the bending angle will become excessive. Further, when the length of the top link is manually controlled to expand or contract, it is difficult to finely adjust the length of the top link using normal means because the inertia of the ground-based work machine is too large.

Problems to be Solved by the Invention This invention solves the problem that the bending angle of the universal joint shaft becomes excessive depending on the lifting height of the ground work machine and its longitudinal inclination angle, and this is not checked. The attitude control device is intended to accurately control the longitudinal attitude of a ground work machine by finely adjusting the length of the top link.

Technical means for solving the problems In order to solve the above problems, the present invention takes the following technical means.

That is, the ground working machine (2), which is connected to the tractor (1) so as to be able to rise and fall through the left and right lower links (+51f5) and the extendable central upper trap (6), is connected to the tractor (m).
It is arranged to be driven by a universal joint shaft (151) connected to the PTO shaft a3 of For each angle of inclination of the machine in the longitudinal direction with respect to the tractor, calculate the standard top link length (Ls) at which the bending angle of the universal joint axis α9 is the most preferable value, and also calculate the safety top link whose bending angle is within a safe range. The target top link length is calculated by calculating the length Lmin) and (Lmax), and adding the correction instruction value (ΔL) instructed by operating the top link length correction switch (81) to the standard top link length Ls). The top link length L) is set to match the target top link length La) if this top link length L) is within the safety top link length Lmin), (Lmax). In addition, when the target top link length La) exceeds the safe top link lengths hni n) and (Lmax), a correction means f201 is provided that corrects the target top link length to match the nearest safe top link length. In the posture control device, an expansion/contraction instruction value (Δ1) corresponding to the number of on/off operations repeated almost without pause is inputted into the above-mentioned correction means (■), whereby the standard top link length Ls) is adjusted to the expansion/contraction instruction value (^). L)? : This added telescopic instruction value (MUL) is a top link telescopic step switch (S) that functions to become O by holding the OFF position. This is a longitudinal attitude control device.

Embodiment and operation Next, one embodiment of the present invention will be explained based on the drawings. Fourth
As shown in the figure, a ground work machine (
As an example of 2), the rotary tiller is connected to a pair of left and right lift arms (3), (to 31), and left and right lift rods (31).
4), (4) are connected by a three-point link mechanism (7) consisting of left and right lower links (5), (5) that swing up and down, and a top link (6) at the upper center. Point linkage mechanism (force is its lift arm + 31
, (3) are lifted and lowered by a hydraulic lifting mechanism that lifts and rotates them using a lift cylinder (8) using hydraulic pressure. The top link (6) is formed to be extendable and retractable by a top link cylinder (9) and a piston (9a), and is operated by a telescopic drive unit a [such as an electromagnetic switching valve] to control the top link of the pressure oil of the oil pump. By controlling the supply and discharge to the cylinder (9), the ground work machine (2) rotates in the front and back direction using the connecting pin αIIQII at the rear of the lower link r5) (5) as a fulcrum, and the ground work machine In order to drive the working part such as the tiller (2), the PTO shaft Q3 of the tractor (1) and the input shaft (14) of the ground work machine (2) are connected by a universal joint shaft (19). There is.

Bending angle of universal joint shaft a9 with respect to PTO shaft (13tlc)
c4 and the bending angle (b) of the universal joint shaft acJ with respect to the input shaft α, as shown in FIGS. Although it varies depending on the height and front-back posture, the conditions under which the universal joint shaft (151) can rotate most smoothly with the least amount of unreasonable force on the joint part are α = β.
These are shown as the most desirable standard curves (At) and (Ah), respectively.

Then, as a condition for sufficiently safe rotation, α+β〈4
0゛, and α−β〈5゛, the former is shown as the safety curve @ (Str) (out +), and the latter is shown as the safety curve (SL2) and (add), respectively. Te(・ro)

Here, FIG. 6 (a) shows the top link (6) at a lower position of the top link mounting frame (161) of the tractor (1) as shown in FIG.
Figure 6 (b) shows the relationship between the lift arm angle () and the top link length υ in the case of a special 3P link that is attached via the top link bracket a'n. Although omitted, the above special 3P
Install the top link (6) at a position above and in front of the IJ link installation position (for example, directly attach the top link mounting frame +1 without going through the top link bracket C1η in Fig. 4).
This figure shows the relationship between the lift arm angle (θ) and the length of the top link in the case of a standard 3P link (mounted at a high position of 61).

Then, a tilt angle sensor (Sθ) consisting of a rotary potentiometer or the like is used to detect, for example, the lift arm angle as the tilt angle of the ground work equipment (2) in the longitudinal direction with respect to the tractor (1). A top link sensor (for example, a linear moving potentiometer) is provided to detect the length of the top link (6).
Based on the lift arm angle (01K) inputted from the tilt angle sensor (Sθ), the calculation means a9 of the control unit a8, which is shown in the control block diagram in FIG. , the standard top link length L relative to each lift arm angle (of
s), safety length Lmin), and (Lmax) are calculated. That is, the calculation means (1!J includes the standard curves (At) in Figures 6 (a) and (b))
, (Ah), safety curve (3t1) + (Stz)t
(Se).

(Sb2) are stored respectively, and either the special 3P link or the standard 3P 17 link is designated in advance by the 3P IJ link mode changeover switch (an). The corresponding standard top link length Ls) etc. are also output from the calculation means 9 and input to the next stage correction means (21).

The correction means (201 includes the top link length L) from the top link sensor C3L) and the top link length correction switch (Sr) provided near the driver's seat as illustrated in FIG. The target top link length (1LI) to be controlled of the top link (6) is calculated by inputting the correction instruction value (aL) and the expansion/contraction instruction value (ΔL) by the top link expansion/contraction step switch (Sz), respectively. be. That is, the top link length correction switch (
St) is the top link control changeover switch (Sz)'
? : It functions only when switching to automatic, and depending on the operating position, the (±) correction instruction value (AL) with respect to the standard top link length Ls at that time is adjusted to the correction means (protection). input.

Top link telescopic step switch (Sz) +'! ,,
It functions regardless of the switching position of the top link control changeover switch (Sz), and if it is turned from the neutral position shown in Fig. 7, that is, the OFF position, to the ON position in the direction of the arrow X (
-1- Conversely, if one person is placed in the on position in the direction of the arrow It is configured so that the expansion/contraction instruction value (ΔL) of -H, which is three times the number of operations (-H), is input to the correction means 1201. , when the top link control changeover switch (S3) is set to manual, the target top link length La) is determined by the expansion/contraction instruction value (Δ) by the top link expansion/contraction step switch (S2).
If you simply add L) to the current top link length L), operate the top link telescopic step switch (S2), and then hold it in the neutral position, the current telescopic command value (ΔL) By adding (@), the target top link length La) returns to its original value.

That is, by turning on and off the top link telescopic step switch (S), the pulse length can be set in advance.
If the correcting means t2B is configured to generate a pulse of It will be output as Δ, and for this, the top link telescopic step switch (
32) 'a' If the above-mentioned fixed time period is exceeded and the OFF position is held, the expansion/contraction instruction value (A1) becomes O, and in this case, the target top link length (Lla) is Ls+Δ
An example of a control block diagram related to this is illustrated in FIG. p'r
Detect whether o-axis a3 is used or not with 4 PTO axis sensor 3), and if PTO axis α is not used, target top link length 1.1) = L + ΔL
shall be. The PTO@Q3 is used with the top link length correction switch (S-ri) and the top link expansion/contraction step switch (correction instruction value (ΔL) by S-uri, expansion/contraction instruction value (A') f!1:, standard Top link length LS
) is added to the target top link length La), and the top link telescopic step switch (S2
) by holding the neutral position, the expansion/contraction instruction value (Δ
L) will be cancelled.

Then, the target top link length La) and the safety top link length Lmin) obtained in this way.

(Lmax) and top link length L) are input to the comparison command means (2υ, and target top link length La)
is the safe top link length (Lenin) to (Lmax
) (it is checked whether it fits or not,
If it deviates from this, the target top link length direction) is corrected to the nearest safety top link length, and then the top link length L) is corrected to the safety top link length Lmi
n) ~ (Lmax), when the PTO automatic cut-off switch is turned off, turn off the PTO axis (command to stop the country?: PTO driving force and top link length L). In order to match the target top link length - 6), a command is given from the comparison command section (21) to the telescopic drive section (10).Instructions for raising and lowering the ground work equipment (2) are given to the raising and lowering position setting device. (11), for example, as a target lift arm angle corresponding to the commanded height,
The lift arm angle (the comparison command unit Qυ is also commanded by the lifting drive unit to match this, but in this case, the standard top link length Ls corresponding to the target lift arm angle), the safety top Link length Lmin),
(Lmax) is not indicated immediately, but an intermediate target lift arm angle is selected that is the current lift arm angle (θ) plus or subtracted by one graduation angle, e.g. 1°, toward the target lift arm angle. The intermediate standard top link length and intermediate safety top link length corresponding to the intermediate target lift arm angle are calculated, and the above-mentioned correction and control are performed based on these. In addition, when the lift arm angle (θ) approaches the target lift arm angle to a certain value, a pulse-like command from the comparison command section is sent to the telescopic drive section OI. is applied to, for example, an electromagnetic switching valve, and the expansion and contraction movement of the top link (6) is slowed down.
Rapid fluctuations in the bending angle (ω, (b) of the universal joint shaft (151) are avoided.

The control block diagram in Figure 1 also shows the basic configurations of automatic tilling resistance control and automatic tilling depth control, but other functions such as left-right attitude control of the ground work machine (2) can also be used at the same time. In addition, auxiliary circuits such as AD and DA converters are omitted in the figure.

In addition to the above-mentioned lift arm (3), a weight attached to the ground work machine (2) or a lower link (5 ) Various methods can be used, such as a method of detecting the longitudinal inclination of the vehicle.

Effects of the Invention The longitudinal attitude control device for a ground-based work machine according to the present invention is configured as described above, and the control device for controlling the longitudinal posture of a ground-based work machine (2) in the longitudinal direction, that is, for each vertical position, The top link (Lmax) is always within (Lmax) from the safety top link length (Lmin) that allows the universal joint shaft (151 to rotate safely).
6) is to be maintained, and the length of the universal joint shaft (1
This will eliminate problems such as damage to the joints caused by excessive bending angle f(2), (/l) of around 50, and the top link telescopic step switch (32
) is turned on and off almost without pause, an expansion/contraction instruction value (A t) corresponding to this on/off operation is added to the standard top link length Ls), and the top link (6
) can now be controlled, so the target top link length (La) can be minutely and accurately specified by the number of on/off operations, which eliminates the variation in on-retention time that occurs with ordinary switches. Therefore, there is no inaccuracy such as variation in the indicated length, and the posture of the ground work machine (2) in the longitudinal direction can be accurately determined.

In addition, if the top link extension switch (S2) is held in the OFF position, the extension@indication value (ΔL) added to the hook will be removed and the original target top link length r, a> will be returned to The restoring operation after controlling the attitude of the working machine (2) has become extremely easy.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a control circuit block diagram, Fig. 2 is a control flowchart, Fig. 3 is a detailed view of the main part of Fig. 1, and Fig. 4 is a side view in a working state. @5
The figures are explanatory diagrams showing the inclination of the universal joint shaft, Figures 6 (a) and (
b) is a characteristic diagram showing the desirable length of the top link, No. 7
The figure is a perspective view of the main parts of the tractor. Code explanation (1)...Tractor (2)...Ground work equipment (5)...Lower link (6)...Top link αJ...PTO@ (19...Universal joint shaft■・・Correction means (Sθ) ・・Inclination angle sensor (La) ・・Target top link length Ls) ・・Advance top link length 81
in), (Lmax) - Safety Top Link Length Patent Applicant: Iseki Agricultural Machinery Co., Ltd. Patent Attorney: Takayoshi Hayashi □'□ Procedural Amendment Lu Showa 64.21 = J288 Patent Application 1987-253776 No. 2゜Name of the invention: Fore-and-aft attitude control device for ground-based work equipment 3.Relationship with the person making the amendment: Address of the person who issued the patent, Iseki Agricultural Machinery Co., Ltd. 4, Agent 7, Contents of the amendment (1) Specification 8th jll line 1-4 “Enough...
As...'' the upper limit of safety at which the free hand sas can rotate sufficiently safely - 1s (st!>, C8h,) and t
fi Lower 1111 safety song 11 (St,), (Sh,)
v, 11116Figure I1,1dKJ! :to correct.

Claims (1)

[Claims] A ground work machine is connected to the tractor via the left and right lower links and the extendable top link at the top of the center, so that it can be raised and lowered, and is driven by a universal joint shaft connected to the PTO shaft of the tractor. The longitudinal posture of the work equipment is controlled by the expansion and contraction operation of the top link, and the bending angle of the universal joint shaft is set to the most preferable value for each inclination angle of the ground work equipment in the longitudinal direction with respect to the tractor. Calculate the standard top link length, calculate the safe top link length where the bending angle is within a safe range, and adjust the correction instruction value specified by operating the top link length correction switch to the standard top link length. Add the target top link length to find the target top link length, and set the target top link length so that the above top link length matches the target top link length if this top link length is within the safe top link length. When the length of the safety top link exceeds the length of the safety top link, the number of on/off operations that are repeated with almost no pause in the attitude control device that has a correction means that makes the correction match the length of the safety top link that is closest to the safety top link. The expansion/contraction instruction value corresponding to the length of the top link is inputted to the correction means, thereby adding the expansion/contraction instruction value to the standard top link length. A longitudinal attitude control device for a ground work machine, which is provided with a top link expansion/contraction step switch that functions so as to be set to zero by the following steps.