JPH0549489B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a power disconnection device for a PTO, and is used for a tractor equipped with a working machine that can be raised and lowered.

(Prior art) In a tractor that is equipped with a working machine such as a rotary tiller that can be raised and lowered at the rear of the tractor and that transmits power from the TPO shaft of the tractor to the working machine, it is possible to till the field and turn the headland. At that time, the tractor was turned after raising the work equipment. When the work equipment was raised during this headland turn, it would be extremely dangerous if the rotary tiller was rotating, so the power to the PTO shaft was cut off by operating the clutch lever. That is, it is necessary to operate the clutch lever at the same time as operating the work implement lifting control lever, which is very troublesome to operate.

In order to simplify the operation, for example, the PTO shaft clutch was automatically disengaged when the working machine rose by a predetermined amount.
It is disclosed in Publication No. 108429.

This conventional PTO auto-stop device (PTO disconnection device) connects the lift arm of the hydraulic device for lifting and lowering the work equipment with the PTO clutch using a link mechanism, etc., and when the lift arm rises a predetermined amount,
When the PTO clutch was disengaged and lowered to a predetermined position, the clutch was engaged.

(Problems to be Solved by the Invention) In the conventional PTO auto-stop device, the PTO clutch is "disengaged" when the work machine is in the ascending position and "engaged" when the work machine is in the descending position, but a problem occurs when the work machine descends. Ta.

In other words, when lowering from a raised position, the rotary work equipment must start rotating before it touches the ground, but because the clutch engages during the descent, the rotary work equipment touches the ground before the rotation has increased sufficiently, resulting in an excessive load on the work equipment. There was a problem with the effect of

In addition, there was a problem in that the PTO clutch could be turned on independently, and it was not possible to select between driving the work equipment before the descending operation and driving the work equipment during the descent.

Therefore, in the present invention, the PTO clutch is automatically disengaged when the work machine is in the up position, and the PTO clutch can be independently "engaged" when the work machine is in the raised position. It is an object of the present invention to make it possible to select a working machine so that it can be put into a driving state and also put a working machine into a driving state even in the middle of descending.

(Means for Solving the Problems) The present invention includes a hydraulic device 11 for vertically moving a working machine 2 bonded to a tractor 1, a control lever 27 for controlling the hydraulic device 11 to raise, lower, and stop the hydraulic device 11;
Transmits the engine power of the tractor 1 to the work machine 2
It is equipped with a PTO transmission system 23, a clutch 24 for connecting and disconnecting the PTO transmission system 23, and a clutch operation lever 25 for connecting and disconnecting the clutch 24, and is spaced apart from each other in the front and back on the side of the driver's seat 13. The control lever 27 and the clutch operating lever 25 are operable in the front and rear directions, and the following technical measures have been taken to achieve the stated purpose.

That is, in the present invention, the clutch operating lever 25 is disconnected when the control lever 27 is placed in the raised position, and the control lever 27 and the clutch are operated so that the clutch operating lever 25 can be operated independently when the control lever 27 is in the raised position. An interlocking means 35 for interlockingly connecting the lever 25 is provided, and the interlocking means 3
5 is a stopper 40 provided on the control lever 27 and a clutch operating lever 2 via the stopper 40.
5, and a push-up lever 41 that pushes up the push rod 36 to release it from the stopper 40 when the control lever 27 is in the raised position. An engaging/disengaging means 48 is provided which engages and disengages from the interlocking means 35 so as to bring the clutch operation lever 25 into contact when the clutch operating lever 25 is operated in the downward direction. An engagement lever 5 that swings up and down and can be freely engaged and detached from the push rod 36 in the means 35
It is characterized by having a value of 0.

(Function) According to the present invention, work is performed by lowering the working machine 2 to touch the ground, and driving the working machine 2 while driving the tractor 1 forward. When the tractor 1 approaches a ridge and changes direction, the lever 27 is rotated so that it is in the work implement raising position. This operation activates the hydraulic system 11, and the working machine 2 rises.

When the control lever 27 is operated in the upward direction, the clutch operating lever 25 is interlocked via the interlocking means 35, and the PTO clutch 24 is disengaged. That is, when the control lever 27 is operated in the upward direction, the stopper 40 pushes the push rod 36, and the clutch operation lever 25 is interlocked in the direction of disengaging the PTO clutch 24. As a result, power is not transmitted to the work implement 2 in the work implement raised position.

The tractor 1 is turned with the working machine 2 raised and its power cut off. When you finish turning and move on to the next task, first press the clutch operating lever 2.
5 to turn on the PTO clutch 24,
After transmitting the power from the tractor 1 to the work machine 2,
Next, the control lever 27 is operated to lower the working machine 2.

The operation of turning on the PTO clutch 24 by operating the clutch operating lever 25 is performed using the control lever 27.
When operating the push rod 36 in the upward direction,
Since the rod 36 is released from the stopper 40 by pushing and lifting it with the lifting lever 41, there is no problem in operating the clutch operating lever 25.
can be operated independently.

Therefore, the rotational speed of the working machine 2 is sufficiently increased when it touches the ground, so that it can touch the ground smoothly.
When the grounding is completed, the tractor 1 is moved forward to continue the work.

In addition, when it is desired to drive the work implement 2 while operating the control lever 27 from the raised position to the lowered position, the engaging/disengaging means 48 provided on the control lever 27 is engaged with the interlocking means 35, and the control is performed in this state. When the lever 27 is operated in the downward direction, the interlocking means 3
5, the clutch operating lever 27 is connected to the clutch 2 via
Switch 4 to "on".

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

In FIG. 4, 1 is a tractor, and a working machine 2, exemplified by a rotary tiller, is attached to the rear of the tractor 1.

The tractor 1 has a vehicle body 6 which includes an engine 3, a clutch housing 4, and a transmission case 5 that are rigidly connected.
The vehicle body 6 is supported by front wheels and rear wheels 7.

The engine 3 is covered with a bonnet 8, the left and right rear wheels 7 are covered with fenders 9, and a cabin 10 is placed on the fenders 9.

A hydraulic device 11 for lifting and lowering the work machine is mounted on the rear upper surface of the transmission case 5, and the upper part of the hydraulic device 11 is covered with a floor sheet 12, and the left and right edges of the floor sheet 12 are fixed to the fender 9. There is. The driver's seat 13 is on this floor seat 12.
is arranged, and an operation handle 1 is placed in front of the driver's seat 13.
4 are provided, and these are covered with a cabin 10.

The hydraulic device 11 is provided with a rearwardly projecting lift arm 15 that is rotatable in the vertical direction, and the lift arm 15 is rotated in the vertical direction by a cylinder within the hydraulic device 11 . A lift rod 16 is pivotally supported at the rear end of the lift arm 15, and the lower end of the lift rod 16 is pivotally connected to a lower link 17 that is pivotally supported on both left and right sides of the transmission case 5 so as to be rotatable in the vertical direction. There is.

Top link 1 on the rear end surface of the transmission case 5
A three-point link mechanism 19 is constituted by this top link 18 and the pair of left and right lower links 17. The working machine 2 is detachably connected to this three-point linkage mechanism 19.

A PTO shaft 20 protrudes from the rear end surface of the transmission case 5, and the PTO shaft 20 and the input shaft 21 of the working machine 2 are interlocked and connected by a universal joint shaft 22.

The PTO shaft 20 is driven by the engine 3,
A clutch 24 for connecting and disconnecting the PTO transmission system 23 in the transmission case 5 is interposed.
This clutch 24 is turned on and off via a link rod 26 etc. by swinging a clutch operating lever 25 located on the right side of the driver's seat 13 in the longitudinal direction.
“Off” operation is performed.

The lift arm 15 of the hydraulic device 11 is raised and lowered by lifting the control valve 29 via the link rod 28 by swinging the control lever 27 located in front of the clutch operation lever 25 in the front and back direction.
This is done by switching to lowering and stopping.

1 and 2, details of the clutch operating lever 25 and control lever 27 are shown.

That is, the clutch operating lever 25 is
It is pivotally supported via a support shaft 31 to a plate 30 fixed to the inner surface of the main body so as to be rotatable in the front and rear directions. At the forward rotational position A of this clutch operating lever 25,
The PTO clutch 24 is in the "on" state, and the power from the engine 3 is transferred from the PTO shaft 20 to the universal joint shaft 22.
The power is transmitted to the working machine 2 via the input shaft 21, and the rotary tilling section 2A of the working machine 2 is rotationally driven.
At the rear rotation position B of the clutch operating lever 25,
PTO clutch 24 is "disconnected" and engine 3
The power is not transmitted to the working machine 2.

The control lever 27 is pivotally supported by a bracket 33 of a base plate 32 fixed on the floor seat 12 via a support shaft 34 so as to be freely rotatable in the front and rear directions. This control lever 27 is operated from C to C in FIG.
The range E is the position control range position, and the position E is the raised position.

That is, by operating the control lever 27 in the position control range position, the control valve 29 is switched via the rod 28, and the lift arm 15 is switched.
is raised and lowered to a predetermined position and held. By holding the lift arm 15 in a predetermined position, the work machine 2
is maintained at a predetermined working position height.

The control lever 27 and the clutch operating lever 25
are interlocked and connected by an interlocking means 35.

That is, the interlocking means 35 is connected to the clutch operating lever 25.
It is comprised of a push rod 36 etc. which is pivotally supported in a forwardly projecting manner so as to be freely rotatable in the vertical direction. The middle part of this push rod 36 is connected to the base plate 32.
It is inserted and held in a long hole 38 of a support plate 37 provided upright on the upper surface. The elongated hole 38 is a vertically elongated hole, and the push rod 36 is vertically swingable within the elongated hole 38.

The tip of the push rod 36 has a screw 36A, and a stopper 39 is provided on the screw so as to be freely threadable. That is, when the lever 27 is in the range C to D, the stopper 4
0 and the contact 39 of the push rod 36 do not contact each other, but are configured to contact within the range D to E.

A push-up lever 41 is pivotally supported on the support plate 37 by a support shaft 42 so as to be vertically swingable. A push-up pin 43 is located at the upper end of the push-up lever 41.
is fixed, and when the push-up lever 41 swings, the push-up pin 43 comes into contact with the push rod 36,
Push the push rod 36 up within the elongated hole 38. Since the center of gravity of this push-up lever 41 is above the pivot portion, the push-up pin 43 tends to rotate downward, so a stopper pin 44 is fixed to the support plate 37 to prevent the downward rotation. .

The control lever 27 includes the push-up lever 4.
1, a link 46 is pivoted on a pin 45 and is pivoted on a pin 47. This link 46 is connected to the push-up lever 41 when the control lever 27 is in the range C to D.
does not come into contact with the rod 36, but it is configured to come into contact in the range D to E.

The link 46 is fixed to the control lever 27, and the push-up lever 41 is not pushed up in the range C to D, but is pushed up in the range D to E.
It may also be in the form of a push rod that pushes up.

Reference numeral 48 denotes a locking/unlocking means, which is provided on the control lever 27.

As shown in FIG. 3, the engaging/disengaging means 48 consists of an engaging lever 50 which is pivoted to be movable up and down by a pin 49 in the middle of the rod of the control lever 27, and a push button 51 for moving the engaging lever 50 up and down. The engagement lever 50 is formed with a cam portion 52 that engages and disengages from the abutment 39 of the push rod 36, and the push button 51 is built into the grip 53 of the control lever 27 and biased in the release direction by a coil spring 54. Engage the interlocking rod 55 with the lever 5
It is pivotally connected to 0.

In addition, in FIG. 1, 56 is a lever guide plate, and in FIG. 3, 57 is a guide portion for the rod 55.

According to the above configuration, when the clutch operating lever 25 is in the A position, the clutch 24 is turned on and the work implement 2 is driven, and the control lever 27 is in the range C to D, and the work implement 2 is in the lowered position for cultivating. do the work.

To raise the working machine 2 when turning on a headland or the like, move the control lever 27 to position E. At this time,
Stopper 40 hits push rod 36 39
and pushes the push rod 36 backward. This pushing movement causes the clutch operating lever 25 to move to A.
Move from position to position B, and press PTO clutch 2.
4 becomes "off".

When moving the control lever 27 from D to E,
The link 46 pushes the push-up lever 41, and the push-up pin 43 moves the push rod 36 upward. When the control lever 27 is in the E position, the push rod 36 is located above the stopper 40 and is no longer in contact with it.

Therefore, when the working machine 2 is in the raised position, the clutch 23 is "disengaged" and power transmission to the working machine 2 is cut off.

Next, when lowering the work machine 2 to move on to the next tilling operation, first move the clutch operating lever 25 from position B to position A, turn the clutch 24 on, and turn the work machine 2 on. Transmit power. At this time, the push rod 36 is pushed upward by the push-up pin 43 and is located above the stopper 40. Therefore, even if the push rod 36 moves forward due to the forward movement of the clutch operation lever 25, the push rod 36 will not stop at the stopper. Do not touch 40.

Thereafter, the control lever 27 is moved from the E position to the D position, and the work implement 2 is lowered. Thus, the rotary tiller 2A of the working machine 2 descends in a rotating state and bites into the ground, resulting in a smooth descent.

When the control lever 27 moves forward, the push-up lever 41 is rotated downward by the push rod 36 and its own weight via the link 46, and is held in contact with the stopper pin 44. As a result, the push rod 36 also descends and returns to its original state.

With the above-described operation, when the control lever 27 is operated to the raised position, the clutch operating lever 25 is automatically switched from "on" to "off", and the clutch operating lever 25 can be operated independently when the control lever 27 is in the raised position. shall be.

Further, when the clutch operating lever 25 is changed from "off" to "on", the engaging/disengaging means 48 provided on the control lever 27 can be brought into the engaged position and operated in conjunction.

That is, when the clutch operating lever 25 is in position B in FIG. When you resist and press down, the rod 55
The cam portion 52 of the engagement lever 50 engages with the contact 39 with the pin 49 as a fulcrum, and this state is held (maintained) and the control lever 27
When the lever is further operated toward the C position, the push rod 36 is retracted by the engagement of the cam portion 52, and the clutch operating lever 25 is switched from the B position to the A position. The tiller 2A is driven slightly before it touches the ground.

When the clutch 24 is turned on and the pressing force of the push button 51 is released, the engagement lever 5
When the control lever 27 is further operated in the C direction, the work implement 2 is lowered and held at a predetermined position.

In FIGS. 1 and 5, reference numeral 58 represents a main clutch operation pedal, which is provided around a support shaft 59 so as to be freely depressed against a spring 60.

The operation pedal 58 is operatively connected to a relay link 61 via a Bowden wire 62, and operates a clutch lever 63 by a link 64.

In this case, the outer mounting bracket 6 of the wire 62
5. Attach the support fitting 66 of the relay link 61 and the latch fitting 68 of the return spring 67 of the clutch lever 63.
A bracket 69 having an integral structure can be attached to and detached from the vehicle body with bolts 70.

(Effect of the invention) According to the present invention, automatically
Since the PTO clutch is disconnected and a single PTO clutch can be connected prior to the lowering operation, safety can be ensured and the work equipment can be grounded smoothly.

That is, the interlocking means for disengaging the clutch operating lever when the control lever is placed in the raised position is a stopper provided on the control lever, a push rod that is pushed through the stopper to disengage the clutch operating lever, and the lifting of the control lever. Since the push-up lever is configured to push up the push rod so as to disengage it from the stopper when the push rod is in the correct position, not only is the operation reliable, but it can also be easily operated from the side while sitting in the driver's seat.

In addition, the control lever is provided with a locking and disengaging means, and the locking and disengaging means can be freely connected and disconnected from the interlocking means, so that the clutch operation lever can be operated independently when the work equipment is in the raised position, and when the clutch is in the disengaged state. It is possible to select whether the switching to the clutch engaged state is performed in conjunction with the hardening operation of the control lever.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is an elevational side view of the main part, FIG. 2 is a perspective view, FIG. 3 is a detailed cross-sectional view of the control lever grip, and FIG. 4 is a side view of the whole. , FIG. 5 is a side view of the main clutch operating section. 1...Tractor, 2...Work equipment, 11...Hydraulic system, 20...PTO shaft, 23...PTO transmission system,
24... PTO clutch, 25... Control lever, 27... Control lever, 33... Push rod, 35... Interlocking means, 37... Clutch operation lever.

Claims (1)

[Scope of Claims] 1. A hydraulic device 11 that moves the working machine 2 mounted on the tractor 1 up and down, a control lever 27 that controls the hydraulic device 11 to raise, lower, and stop, and the tractor 1.
The present invention includes a PTO transmission system 23 for transmitting engine power to the working machine 2, a clutch 24 for connecting and disconnecting the PTO transmission system 23, and a clutch operating lever 25 for connecting and disconnecting the clutch 24.
In the case where the control lever 27 and the clutch operating lever 25 are spaced apart from each other in the front and rear directions on the side of the driver's seat 13 and can be operated in the longitudinal direction, the clutch operating lever 25 is disconnected when the control lever 27 is placed in the raised position. At the same time, when the control lever 27 is in the raised position, the clutch operating lever 25
An interlocking means 35 is provided which interlocks and connects the control lever 27 and the clutch operation lever 25 so that the control lever 27 and the clutch operating lever 25 can be operated independently.
When the push rod 36 and the control lever 27 are in the raised position, the push rod 36 is pushed through the stopper 40 to disconnect the clutch operating lever 25.
Push-up lever 41 that pushes up so as to separate from 0
The control lever 27 is provided with an engagement means 48 that engages and disengages from the interlocking means 35 to bring the clutch operation lever 25 into contact when the control lever 27 is operated in the downward direction. Means 48
A PTO power disconnection device characterized in that it has an engagement lever 50 that is provided on the control lever 27 and swings up and down and can be freely engaged with and detached from the push rod 36 of the interlocking means 35.