JPH0120184Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a power extraction device for transmitting power to a working machine in a tractor.

Traditionally, tractors have a power take-off shaft (PTO) to transmit power to the work equipment attached to it.
In addition, some power take-off shafts are equipped with a safety device that automatically cuts off power transmission when the working machine is raised.

However, with conventional safety devices such as those mentioned above, if the work equipment is lowered due to incorrect operation, even during breaks or inspections, power is transmitted to the work equipment, which is dangerous and impractical for safety measures. It was a problem.

The purpose of the present invention is to eliminate the above-mentioned inconveniences in terms of safety measures of the conventional devices.The present invention is equipped with a clutch that connects and disconnects the power to the power take-off shaft of the tractor, and the clutch is attached to the tractor. An automatic power cut-off mechanism is provided that is linked to the lifting and lowering of the work equipment and turns the clutch ``on'' in the working position and ``off'' in the non-working position. By providing a release mechanism in parallel with the automatic power cutoff mechanism to set the clutch in the ``off'' position, a safety stop mechanism is constructed in which the clutch is in the ``off'' position regardless of the vertical position of the work equipment.
To provide a power take-off device for a tractor, which is capable of cutting off the power of the working equipment whenever the tractor stops running, and reliably preventing dangers caused by inadvertent activation of the working equipment during breaks or inspections. That is.

The structure of the present invention will be described with reference to an embodiment shown in the drawings. In FIG. 1, 1 is a tractor;
Reference numeral 2 denotes the driver's seat, and 3 is a driving operation panel. The driving operation panel 3 is provided with a driving handle 4 and a speed change lever 5 of a traveling system transmission mechanism. Further, 6 is a tow hit, 7 is a hydraulic lift arm, and 8 is a power take-off shaft (PTO), and a working machine (not shown) attached to the rear of the tractor 1 is a hydraulic lift arm 7.
The shaft is raised and lowered by a shaft 8, and power is transmitted from a power take-off shaft 8.

As shown in FIGS. 2 and 3, the power take-off shaft 8 is provided with an electromagnetic clutch 9 that connects and disconnects power. The electromagnetic clutch 9 is turned off when energized, and turned on when not energized, and is connected to a power source with the following circuit configuration. That is, 10 is an automatic stop switch, 11 is a safety switch, and 12 is a release switch. A safety switch 11 is a manual opening/closing switch and is provided on the operation panel 3, and a release switch 12 is provided corresponding to the gear shift lever 5 of the drive system transmission mechanism. Its neutral position N
It is located in the closed position. The automatic stop switch 10 and safety switch 11 are connected in series between the electromagnetic clutch 9 and the power supply, and the release switch 12 is connected in parallel with the automatic stop switch 10, and is connected in series with the electromagnetic clutch 9 and the power source. The electromagnetic clutch 9 is connected to the lifting and lowering of the work equipment and is turned on in the working position and turned off in the non-working position. A release mechanism is configured, and the release mechanism and safety switch 1
1 constitutes a safety stop mechanism that is turned off regardless of the vertical position of the working machine. The safety switch 11 is always closed and opened when necessary.

In the device configured as described above, if the work equipment is lowered to the working state and the gear shift lever 5 is placed in a position other than the neutral position N (1, 2, 3, R) to enter the running state, the machine will stop automatically. Both the switch 10 and the release switch 12 are opened, and the electromagnetic clutch 9 is not energized and the clutch is turned on. Therefore,
The power take-off shaft 8 rotates and power is transmitted to the working machine. However, when the gear lever 5 is placed in the neutral position N to stop the aircraft from moving during a temporary stop, etc., the release switch 12 connected in parallel with the automatic stop switch 10 closes and the electromagnetic clutch 9 is energized. Therefore, the clutch is "disengaged" and the power take-off shaft 8 does not rotate, and the operation of the working machine is automatically stopped. The power to the working machine is cut off by the release switch 12, regardless of the vertical position of the working machine, when the gear shift lever 5 is placed in the neutral position N, thereby ensuring work safety. Note that if the work equipment is raised and placed in the non-working position while the machine is running, the automatic stop switch 10 will close and the electromagnetic clutch 9 will be energized, which will turn it off and the power of the work equipment will be reduced. automatically blocked.

By the way, when the machine body is stopped to inspect or adjust the work equipment, the shift lever 5 is in the neutral position N and the release switch 12 is closed.
Even if the work equipment is lowered, it does not operate.
However, if it is necessary to make inspections, adjustments, etc. with the work equipment in operation, open the safety switch 11 and cut off the power to the electromagnetic clutch 9.
The power take-off shaft 8 can be rotated to put the work machine into a working state. It should be noted that when the inspection and adjustment of the operating state is completed, if the safety switch 11 is immediately returned to the closed position, the power of the working machine can be cut off and danger can be prevented from occurring.

In short, the present invention includes a clutch that connects and disconnects the power to the power output shaft of the tractor, and engages the clutch in the working position in conjunction with the lifting and lowering of the working equipment attached to the tractor, and in the non-working position. "cut"
In addition to providing an automatic power cut-off mechanism, a release mechanism is provided in parallel with the power automatic cut-off mechanism to disable the clutch in its neutral position in conjunction with the tractor's travel gear change mechanism. Since it is configured with a safety stop mechanism that turns off regardless of the lifting position, the power of the working equipment can be automatically interrupted in conjunction with the lifting and lowering of the working equipment, and even when the tractor stops running. Since the release mechanism linked to the traveling gear shift mechanism is installed in parallel with the automatic power cut-off mechanism, the power to the work equipment is always cut off regardless of the lifting or lowering position of the work equipment, preventing accidental damage during breaks or inspections. This has very useful practical effects, such as being able to reliably prevent dangers caused by the operation of the working machine and ensuring work safety.

[Brief explanation of the drawing]

The drawings show an embodiment of the power extraction device for a tractor according to the present invention, in which Fig. 1 is an overall side view of the tractor, Fig. 2 is an explanatory diagram showing the configuration of the main parts, and Fig. 3 is an illustration of the main parts. FIG. In the figure, 1 is the tractor, 3 is the driving control panel, 5 is the gear shift lever of the driving system transmission mechanism, 7 is the hydraulic lift arm, 8 is the power take-off shaft, 9 is the electromagnetic clutch, 10 is the automatic stop switch, and 11 is the safety switch. , 12 is the release switch, , is the power supply, N is the gear shift lever 5
is the neutral position.

Claims (1)

[Claims for Utility Model Registration] (1) The power output shaft of the tractor is equipped with a clutch that connects and disconnects the power, and the clutch is turned on and off at the working position in conjunction with the lifting and lowering of a working machine attached to the tractor. An automatic power cut-off mechanism is provided that disables the clutch in a non-working position, and a release mechanism that is linked to the tractor's travel gear shift mechanism and disables the clutch in its neutral position is provided in parallel with the automatic power cut-off mechanism. A power extraction device for a tractor, characterized in that a safety stop mechanism is configured to disengage the clutch regardless of the ascending/descending position of the working machine. (2) The above safety stop mechanism operates by turning the clutch on and
2. The power extraction device for a tractor according to claim 1, further comprising a manual operation mechanism for turning the power off.