JPS5850810Y2 - Mobile ground work equipment - Google Patents

Description

[Detailed description of the invention] The present invention relates to a mobile ground-based work machine in which the operation of a lifting device that drives and lowers a ground-based work equipment connected to the machine body can be switched using a human operating tool provided in the control section. be.

In the above-mentioned mobile ground-based work equipment, the rotary work device is kept aloft while traveling on the road, but since the operating tool for the lifting device is located in the control section, there is a risk of accidentally operating it and lowering the work device. was there.

This invention focuses on the fact that the PTO shaft for power transmission to the work equipment must be stopped when traveling on the road, and effectively utilizes this PTO shaft stop operation to prevent the accidental lowering of the work equipment when traveling on the road. It is.

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

FIG. 1 shows a mobile ground working machine in which a rotary tilling device 1 as a ground working device is attached to the rear of a tractor main machine 2 so that it can be raised and lowered. In addition to driving the tilling device 1, a hydraulic pump (not shown) is operated, and a hydraulic control valve (described later) which is appropriately switched and activated by an electric control signal is operated, and the tilling device 1 is operated as a single-acting lifting device. The hydraulic cylinder 5 is telescopically operated to cause a lift arm 6 connected to the cylinder 5 to swing up and down, thereby driving the tilling device 1 suspended and supported by the lift arm 6 up and down.

The hydraulic cylinder 5 is configured to be automatically controlled based on changes in the load of the engine 3 and changes in the relative height of the tilling device 1 with respect to the tractor 2, the details of which will be explained in the block diagram of FIG. 2. .

A signal E from a detector 7 that detects the actual rotational speed of the engine 3 and a signal A from a rotational speed setter 8 that sets the maximum engine rotational speed according to the accelerator set are applied to a first subtractor 9. The arrangement is such that the engine load is detected as the amount of decrease in engine rotational speed (A-E).

Further, the signal from the first subtractor 9 and the signal H from the plowing depth setting device 10 for adjusting the relative level of the tilling device 1 with respect to the tractor to change the target plowing depth are applied to the adder 11. , the output signal from the adder 11 and the signal from the level detector 12 for detecting the relative level of the tilling device 1 with respect to the tractor 2 are applied to a second subtractor 13, and the respective detection and setting devices 7, 8 . Due to the balanced relationship between the signals from 10 and 12, a signal for determining whether to raise or lower the tilling device 1 is taken out from the second subtractor 13 in view of the change in engine load and the set plowing depth value. .

In other words, the signal voltage A-E from the first subtractor 9 increases as the engine speed decreases, and the plowing depth set value 10 and the signal voltage H from the level detector 12 and the soil increase as the plowing depth increases. If the tilling device 1 is located shallower than the set plowing depth position while the engine rotation speed is decreasing, the rotation speed decrease amount (engine load)
A-E>0 and deviation amount H-L< from the set plowing depth of tilling device 1
If O is equal, the output voltage from the second subtractor 13 becomes zero, and it is determined that the tilling device 1 does not need to be raised or lowered.If the engine speed reduction amount A-E increases from this state, the second subtractor 13 The first discriminator 14 determines that the tilling device 1 needs to be raised because the output voltage becomes positive, and conversely, when the engine speed reduction amount A-E decreases, the second subtractor 13 determines that the tiller 1 needs to be raised. The output voltage becomes negative, and the second discriminator 15 determines that the tilling device 1 needs to be lowered.

The tiller 1 is then adjusted so that the balance relationship is established based on the change in engine speed reduction as the tiller 1 is raised and lowered and the change in the signal from the level detector 12.
Elevation control is performed.

In other words, if the output voltage from the second subtractor 13 is positive,
The lifting valve 16 of the hydraulic cylinder 5 is opened to drive the lift arm 6 to swing upward, and conversely, when the output voltage is negative, the hydraulic cylinder 5 is opened so that the lift arm 6 and the tilling device 1 are lowered by their own weight. It is configured to open the descending valve 17.

Further, in the output circuit of the tillage depth setting device 10, a switch 19 is provided which can be switched and connected to the setting device 18 to which a sufficiently large positive constant signal is set.
By manually inputting the fixed signal from the setting device 18 to the adder 11 in place of the signal H from the setting device 10, the output from the second subtractor 13 is made positive, and the tilling device 1 can be operated even during automatic control. It is configured so that it can be operated upward, and if the switch 19 is returned to its original state, it can return to the above-mentioned control again.

This switch 19 is configured to be operated by a snap lever 21 (manual operation tool) provided on the support of the control handle 20.

Further, the control section of the tractor 2 is provided with a lever 23 for changing the speed of the PTO shaft 22 for transmitting power to the tilling device 1, and a lever 23 is provided to detect that the lever 23 is in a neutral position. A switch 24 is equipped to

This switch 24 is connected in series with the switch 19 and in parallel with the setting device 18, and when the lever 23 is in the neutral position, a fixed signal from the setting device 18 is sent to the adder 11 regardless of the switching of the switch 19. configured to communicate.

According to the above configuration, the tilling device 1 can be raised and floated, and the PTO
When driving on the road with the shaft 22 stopped, the snap lever 21
Even if the tiller 1 is operated unexpectedly, the tilling device 1 will not be controlled to descend.

Furthermore, based on the neutral detection of the lever 23, the snap lever 2
1 may be fixed, or the main switch of the control circuit may be turned off.

As described in detail in the embodiments above, the present invention makes effective use of the fact that the PTO shaft is always stopped when driving on the road.
It is possible to disable the operation of the lifting device that drives and lowers the working device without requiring any special operation, and thereby it is possible to reliably prevent the working device from lowering even if the lifting device operating tool is accidentally operated while driving on the road. It became.

[Brief explanation of the drawing]

The drawings show an embodiment of the mobile ground work machine according to the present invention, with FIG. 1 being an overall side view and FIG. 2 being a control block diagram. 1...Ground work equipment, 2...Airframe, 5
...lifting device, 21 ...human operation tool,
22...PTO shaft, 23...PTO shaft variable shaft circumferential speed lever 4...Switch.

Claims (1)

[Scope of Claim for Utility Model Registration] ■ A mobile ground-based working machine configured to switch the operation of a lifting device 5 for driving and lowering a ground-based working device 1 interlockingly connected to a machine body 2 using a human operating tool 21 provided in a control section, Aircraft 2
A mechanism is provided for detecting that the rotation of the PTO shaft 22 for driving the working device installed in the work device is stopped, and when the PTO shaft is stopped, it is impossible to switch the operation of the lifting device 5 by the operating tool 21. mobile ground-based work equipment. ■ The mechanism that detects two rotation stops within the two PTO axes is
Switch 24 for detecting the vertical position of lever 23 for shaft circumferential speed
A mobile ground-based working machine according to claim 2 of the utility model registration claim.