JP2000342014A - Small-size sulky-type working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject working machine capable of securing the safety of an operator by constituting the working machine so that the transmission of the power from an engine to a PTO shaft may be cut synchronously to a specific operation, and further the operation means of a PTO clutch may be slowly returned. SOLUTION: This small-size sulky-type working machine having various kinds of operation parts connected to the rear part of a self-propelled traveling part B through a lifting and lowering structure 1, and an input shaft 24 installed in the various kinds of the operation parts and connected to an engine E mounted on the traveling part B through the PTO shaft 22, is constituted so that the transmission of the power from the engine E to the PTO shaft 22 may be cut synchronously with the braking operation of the traveling part B, and the PTO clutch-operating means may be slowly returned when cutting the.transmission of the power to the PTO shaft 22 synchronous to the braking operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small riding work machine.

[0002]

2. Description of the Related Art Conventionally, as one form of a small riding work machine,
Some working units are connected via a lifting mechanism to the rear of the self-propelled traveling unit, and some engines mounted on the traveling unit are connected to input shafts provided for the various working units via a PTO shaft. .

[0003]

However, in the small-sized riding work machine described above, for example, when a rotary-type tilling section as various working sections is connected to the rear of the running section to perform a tilling operation, a field is added to the running section. If the tilling portion is lowered while the tilling portion is operated while the tilling portion is running, the tilling portion may receive a reaction force of the plow, and the machine body may suddenly start, that is, so-called dashing.

[0004] At this time, even if the operator operates the brake operating means, the tilling operation of the tilling portion does not stop.
Separately, it is necessary to perform an operation for stopping the tilling operation of the tilling unit, but it is difficult to perform these two operations in an emergency, and there is a problem that safety cannot be ensured.

[0005] In view of this, the power transmission of the PTO clutch interposed between the engine and the PTO shaft is configured to be cut off in conjunction with the brake operation of the traveling unit, and the tilling operation of the tilling unit is stopped simultaneously with the brake operation. It is conceivable to prevent the risk of dashing by doing so.
Since the operating part of the TO clutch, for example, the PTO clutch lever suddenly returns to the disengaged position by the bias of the clutch spring, it may hit the operator's body and cause injury, or this shock may cause an erroneous operation.

Also, if the transmission of the traveling section is in the forward or reverse state when the brake is operated, it is dangerous because the aircraft suddenly starts running when the brake operation is inadvertently stopped. There is a problem that it causes surprise operation.

Accordingly, a neutral position return mechanism for returning the forward / reverse switching lever and the transmission to the neutral position in conjunction with the brake operation of the traveling unit is provided below the step. It is conceivable to automatically return the forward switching lever and the transmission to the neutral position,
Since the neutral position return mechanism is disposed below the step of the vehicle body, there is a possibility that malfunction or malfunction may occur due to adhesion of mud or the like.

[0008]

Therefore, according to the present invention, various working units are connected via a lifting mechanism to the rear of a self-propelled traveling unit, and the engine mounted on the traveling unit is provided in the various working units. In a small passenger work machine in which the input shaft is interlocked and connected via the PTO shaft, the power transmission from the engine to the PTO shaft is cut off in conjunction with the braking operation of the traveling unit,
Further, the present invention provides a small riding work machine characterized in that the PTO clutch operating means is configured to return slowly when power transmission to the PTO shaft is cut off in conjunction with the brake braking operation.

The present invention has the following features.

A brake operating means is interlockedly connected to a brake device provided in the traveling section, while a PT
A PTO clutch operating means is interlockedly connected to a PTO clutch for connecting and disconnecting power transmission to the O-axis, and the PTO clutch operating means and the brake operating means are interlockedly connected via a clutch forcible disconnection mechanism to force the clutch. The disconnection mechanism interlocks the brake braking operation of the brake operating means with the PTO clutch disconnecting operation of the PTO clutch operating means to cut off the power transmission to the PTO shaft during the brake braking operation. Between the clutch and the brake braking operation, P
An interlocking operation canceling mechanism for canceling the interlocking operation between the TO clutch operating means and the PTO clutch is interposed, and the power transmission to the PTO shaft is cut off by the brake braking operation.
Release the interlocking operation between the O-clutch operating means and the PTO clutch, and slowly return the PTO clutch operating means.

The traveling unit includes a transmission unit that switches the driving direction between forward and backward by operating a forward / reverse switching lever. The transmission unit and the forward / reverse switching lever are neutralized in conjunction with a brake braking operation of the traveling unit. A neutral position return mechanism has been provided to restore the state.

In the neutral position return mechanism, an operation plate having a substantially triangular operation hole formed at the base end of a forward / reverse switching lever is continuously provided, and the operation plate is interlocked with an operation receiving portion of the transmission portion. By inserting a roller that operates substantially linearly in conjunction with the braking operation of the brake pedal into the operation hole and tilting the operation plate so that the roller is positioned at one corner of the operation hole during the braking operation, Returning the forward switching lever and transmission to the neutral state.

[0013] The neutral position return mechanism is disposed in a handle column erected on the upper surface of the floor of the traveling section.

[0014]

Embodiments of the present invention will be described below.

That is, in the small riding work machine according to the present invention, various working parts are connected to the rear of the self-propelled running part via an elevating mechanism, and the engine mounted on the running part has:
The input shafts provided in the various working sections are interlocked and connected via a PTO clutch, and the PTO clutch and a brake pedal as a brake operating means are interlocked and connected via a clutch forcible disconnection mechanism. At this time, in conjunction with the braking operation of the brake pedal, PT
The power transmission of the O-clutch is automatically cut off to stop the operation of the work machine to prevent dashing.

Further, an interlocking operation release mechanism for connecting / disconnecting the transmission of the operation of the PTO clutch lever is provided between the PTO clutch lever as a PTO clutch operating means disposed in the driving section and the PTO clutch, and the interlocking operation is performed. The operation release mechanism and the brake pedal are interlockingly connected, and the operation transmission of the interlocking operation release mechanism is cut off in conjunction with the braking operation of the brake pedal, so that the power transmission of the PTO clutch is transmitted regardless of the operation position of the PTO clutch lever. The clutch can be disengaged, and the PTO clutch lever is released from the bias of the clutch spring. On the other hand, the PTO clutch lever is spring-biased in the direction of the disengagement position so that the PTO clutch lever is slowly returned to the power transmission disconnection position. ing.

An operation transmission mechanism between a forward / reverse switching lever for controlling the traveling direction of the vehicle body and an operation receiving portion of a transmission unit having a forward / reverse switching function is provided inside a handle column free of adhesion of mud or the like. In addition, a neutral position return mechanism is interposed, and the forward / reverse switching lever is returned to the neutral position in conjunction with the braking operation of the brake pedal, so that the traveling drive is cut off. I try to prevent malfunction.

That is, an operating plate having a substantially inverted triangular operating hole is continuously provided at the base end of the forward / reverse switching lever, and the forward / backward switching lever can be tilted via a support shaft above the operating plate. On the other hand, a return link is provided that operates downward in conjunction with the braking operation of the brake pedal, and a roller is rotatably supported at the upper end of the return link, and the roller is inserted into the operation hole. The roller is rolled on the slope of the operation hole by the downward operation of the roller in conjunction with the braking operation of the brake pedal, and the forward / reverse switching lever connected to the operation plate is returned to the neutral position by this reaction force. I have.

One end of a forward wire and one end of a reverse wire are connected to the front and rear ends of the operation plate, respectively, and the other end of each wire is connected to an operation receiving portion of the transmission, so that the forward / reverse switching lever is in a neutral position. The return operation is transmitted to the transmission.

[0020]

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

A shown in FIG. 1 is a small riding work machine according to the present invention.
And a rotary tillage section C as one form of various working sections is connected to the lifting mechanism 1 via a hitch 2 which can be easily connected and released.

As shown in FIG. 1, the traveling section B bends a thick steel pipe to surround the outer periphery of the fuselage in plan view, and connects a low front portion and a high rear portion in side view. A sub-frame 4 is formed by connecting a sub-frame 4 formed by bending a thin steel pipe to form a front horizontal portion and a rear rising portion, below a main frame 3 formed in an annular shape by being connected at an intermediate portion inclined to a rear height. A body frame 5 having a substantially rectangular frame shape in a plan view is formed, a transmission portion 6 is disposed at a substantially central portion of the body frame 5, and a front wheel drive shaft case 7 serving also as a king pin is provided on each of left and right sides of the transmission portion 6. A front wheel 9 is mounted on each front wheel drive shaft case 7 via a front axle 8, and a rear axle case 10 is disposed on the left and right rear portions of the body frame 5. Mount rear wheel 12 via axle 11,
Interlocking shafts 13 are interposed between the left and right sides of the transmission 6 and the left and right rear axle cases 10, respectively.

In the drawing, 14 is a roll bar, 15 is a side cover, 16 is a front wheel fender, and 17 is a rear wheel fender.

A driving unit is provided at the front of the upper surface of the body frame 5.
18 and a motor unit 19 is disposed between the transmission unit 6 and the left and right rear axle cases 10. The transmission unit 6 is connected to an engine E provided in the motor unit 19 via a traveling drive belt 20. Linked and linked.

At the rear end of the sub-frame 4, a pair of left and right working unit connectors 21 is provided to protrude rearward.
The PTO shaft 22 is laid horizontally between 21 and the fuselage frame 5 and the hitch 2
And a lifting mechanism 1 for raising and lowering the hitch 2 about a PTO shaft 22 is provided between the lifting mechanism 1 and the hitch 2.
And the tillage part C connected to the hitch 2 is moved up and down.

The PTO shaft 22 is connected to the engine E by the PT.
The input shaft 24 of the tilling unit C is interlockingly connected to the PTO shaft 22 via an O-clutch 23 via a transmission case (not shown), and the engine E → PTO clutch 23 → PTO shaft 22
→ Power is transmitted in the order of the input shaft 24 of the tilling section C.

The PTO clutch 23 is, as shown in FIG.
The driving pulley 26 is fitted to the output shaft 25 of the engine E,
A passive pulley 27 is fitted to the left end of the TO shaft 22, and each pulley 2
While a PTO clutch belt 28 is wound with a predetermined slack between 6, 27 and 27, an intermediate portion of a clutch operating arm 30 having one end pivotally supporting a floating pulley 29 is provided via a pivot 31 protruding from the body. The clutch spring 32 is pivotally attached to the other end of the clutch operating arm 30 and the rear end of a clutch spring 32 composed of a tension coil spring extending in the front-rear direction is locked at the other end of the clutch operating arm 30. 29 is pressed against a PTO clutch belt 28 to apply tension to the PTO clutch belt 28, whereby power is transmitted between the driving pulley 26 and the passive pulley 27, the clutch spring 32 is relaxed, and the floating pulley 29 is released. Is separated from the PTO clutch belt 28, the tension of the PTO clutch belt 28 is lost and the power transmission is cut off.

As shown in FIG. 1, the driving section 18 extends the floor 34 along the refraction of the upper surface of the main frame 3 from the front of the body frame 5 to the front of the seat 33 below the front end thereof. A handle column 35 is erected on the handle column 35, and a handle 36 is mounted on the upper end of the handle column 35 so as to be operably rotatable, and a brake pedal 37 as a brake operating means is provided on the right side of the handle column 35 on the floor 34. Arrange,
A brake lever 38 is provided for the operator who gets off the brake pedal 37 to manually perform a brake operation from the front.

A forward / reverse switching lever 39 is mounted on the left side wall of the handle column 35, and an accelerator lever 40 is mounted on the right side wall.
Is installed.

A shift lever 41 is disposed on the left side of the seat 33, and a working unit lifting / lowering operating lever (not shown) and a PTO clutch operating lever as PTO clutch operating means are provided on the right side of the seat 33. 42 and working depth adjustment lever 43
A control valve (not shown) connected to the lifting mechanism 1 is provided near the working unit lifting operation lever.

Next, the mounting structure of the brake pedal 37 will be described.

That is, as shown in FIG. 1, between the left and right support brackets 44 projecting from the front lower surface of the main frame 3,
A brake shaft 45, which is interlocked with a brake mechanism (not shown) of the traveling unit B, is supported by a shaft, and the brake pedal 37 is mounted on the brake shaft 45 via a pedal arm 46 bent in a substantially rectangular shape. Wire mounting arm on the same brake shaft 45
47, the front end of the forcible cutting wire 48 is connected to the distal end of the wire mounting arm 47, and the rear end of the forcible cutting wire 48 is connected to a clutch forcible cutting mechanism 49 and an interlocking operation release mechanism 50, which will be described later.
And is linked to

As shown in FIGS. 2 to 4, the PTO clutch operation lever 42 has a plate-like mounting base 51 extending in the front-rear direction on the left side of the transmission section 6, and the mounting base 51 is provided.
A PTO clutch operation shaft 52 extending in the left-right direction is supported between the shaft and the transmission unit 6, and an arm boss 53 is provided inside the outer protruding end of the clutch operation shaft 52, and a lever boss 54 is provided individually rotatable outside. And the lever boss 54 has a PT
The base end portions of the O-clutch operating lever 42 and the clutch operating body 55 are fixed to each other so that the PTO clutch operating lever 42 can be tilted between an upper power transmission disconnecting position P1 and a forward power transmission connecting position P2. , Arm boss 53 with clutch operation arm
The base end of the clutch operation arm 56 is fixed, and the front end of a clutch operation relay rod 57 bent in a substantially elliptical shape is pivotally connected to the distal end of the clutch operation arm 56, and the rear end of the clutch operation relay rod 57 is pivoted. Is connected to one end of a bell crank 59 composed of lever bodies 59a and 59b projecting out of phase at both ends of an intermediate shaft 58 pivotally supported on the upper surface of the subframe 4, and the other end of the bell crank 59 is connected to the other end of the bell crank 59. The front end of the clutch spring 32 is locked.

A return spring 60 composed of a torsion coil spring thicker than the locking urging spring 65 is interposed between the clutch operating body 55 and the clutch operating arm 56 so that the clutch operating body 55 On the other hand, the PTO clutch operation lever 42 connected to the clutch operation arm 56 is moved to the power transmission disconnection position.
It is urged to rotate in the P1 direction.

The interlocking operation releasing mechanism 50 is a round bar-shaped locking member 61 projecting leftward from the left side surface of the clutch operating member 55.
And a hook 63 rotatably pivoted via a pivot 62 projecting from the clutch operation arm 56.
A locking concave portion 64 is formed on the lower surface of the distal end portion of the 63, and the hook 63 is urged downward by a locking urging spring 65 composed of a thin torsion coil spring, so that the PTO clutch operation lever 42 is in the power transmission cutting position P1. When the locking member 61 is in the position, the locking body 61 is recessed into the locking recess 64, the clutch operation arm 56 and the PTO clutch operation lever 42 are interlocked and connected, and the PTO clutch operation lever 42
Following the operation to the power transmission connection position P2, the clutch operation arm 56 rotates and pulls the front end of the clutch spring 32 forward to apply tension to the clutch spring 32,
Power can be transmitted to the PTO clutch 23.

The clutch operation arm 56 that has reached the power transmission connection position P2 in this manner is connected to the clutch operation relay rod 57.
Is bent in a substantially elliptical shape, and interference with the PTO clutch operation shaft 52 is avoided, so that the clutch spring 32 can be slightly rotated slightly more than the most extended position, and stable at that position. And the power transmission connection state of the PTO clutch 23 can be maintained.

The clutch forcible disconnection mechanism 49 includes the hook 63
A substantially round rod-shaped contact body 66 is protruded from the right side of the tip of the mounting base 51, and is viewed from the side through a pivot 67 protruded at a position obliquely above the PTO clutch operation shaft 52 on the right side of the mounting base 51. The upper end of a plate-shaped cutting operating body 68 bent into a substantially L-shape is pivotably connected to the upper end, and the distal end of the cutting operating body 68 is positioned below the contact body 66 at the power transmission connection position P2. At the same time, the forcible cutting wire
When the rear end of the forcible cutting wire 48 is pulled by the braking operation of the brake pedal 37 by connecting the rear end of the
The upper surface of the distal end of 68 pushes up the contact body 66, and the locking body 61 escapes from the locking recess 64 of the hook 63, whereby the interlocking connection between the clutch operating body 55 and the clutch operating arm 56 is released, and the clutch operating arm is released. 56 is rapidly rotated in the direction of the power transmission disconnection position P1 by the bias of the clutch spring 32, and loses the biasing force of the clutch spring 32, thereby disconnecting the power transmission of the PTO clutch 23. On the other hand, the PTO clutch operation lever 42 is slowly returned to the power transmission connection position P2 by the bias of the return spring 60, and the locking body 61 is inserted into the locking concave portion 64 of the hook 63 that has been returned earlier, so that the PTO clutch The operation lever 42 and the clutch operation arm 56 can be returned to the interlocking connection state.

As long as the braking operation of the brake pedal 37 is not performed, the releasing operation of the interlocking operation releasing mechanism 50 is not performed, and the interlocking connection between the clutch operating body 55 and the clutch operating arm 56 is not released. By operating the PTO clutch operation lever 42, the power transmission of the PTO clutch 23 can be connected or disconnected. In the figure, reference numeral 69 denotes a stopper for regulating the power transmission cutting position P1 of the clutch operation arm 56, and reference numeral 70 denotes a length adjustment unit provided at a middle portion of the clutch operation relay rod 57 and including a fixing nut, a bolt, and a long hole. .

Next, the tilling part C will be described. As shown in FIG. 1, the tilling part C is provided with a tilling shaft 72 extending in the left-right direction in a transversely penetrating manner below the tilling transmission case 71, as shown in FIG.
A large number of tilling claws (not shown) are planted on the tilling shaft 72 to form a rotary cultivating portion C. An upper half of the outer circumference of the cultivating claw is covered with a rotary cover 73. The front edge of the rear cover 74 is pivotably supported on the rear edge of the rear cover 74 so that the rear end of the rear cover 74 can swing up and down along the top surface of the cultivated soil. The control signal is transmitted to a control valve (not shown) connected to the elevating mechanism 1 via a rod 75 and a feedback wire 76, and the height of the tilling portion C is feedback-controlled to maintain a constant plowing depth. I have. In the figure, reference numeral 77 denotes the rotation locus of the tip of the tilling nail.

In the tilling part C, the tilling work is performed by rotation of the tilling nails. Therefore, when the tilling part C is lowered and the tilling nails are grounded while the tilling nails are rotated, the resistance of the tilling nails is reduced. The small riding work machine A may be dashed by the reaction force, and there is a problem that the braking force is reduced when a brake braking operation is performed on the traveling unit B during the tilling operation.

With the above-described structure, when the operator operates the brake pedal 37 to perform the braking operation, the clutch forcible disconnection mechanism 49 is provided.
Is activated, the power transmission of the PTO clutch 23 is rapidly disconnected, and the rotation of the tilling claw of the tilling portion C is stopped, so that the risk of dashing can be prevented, and at the same time, the interlocking operation release mechanism 50 Is activated and the clutch operation arm 56 and PT
The connection with the O clutch operation lever 42 is released, and the PTO clutch operation lever 42 is slowly returned to the power transmission disconnection position P1 by the bias of the return spring 60.

As described above, the seemingly contradictory operations of rapid disconnection of the power transmission of the PTO clutch 23 and slow return of the PTO clutch operation lever 42 can be realized by simply performing the braking operation. Etc. can be avoided.

FIGS. 6 to 8 show a neutral position return mechanism 101 for returning the forward / reverse switching lever 39 to the neutral position in conjunction with the braking operation of the brake pedal 37. The neutral position return mechanism 101 comprises: A bearing 103 is protruded from the middle front surface of the handle shaft case 102 which is inserted substantially vertically through the handle column 35, and a lever support shaft 104 extending in the left and right direction is rotatable via the bearing 103. Pivoted, same lever spindle
A central portion of the upper side of an operation plate 105 having an inverted triangular shape in side view is fixed to one end of the operation plate 104, and an operation hole 106 having an inverted triangular shape in side view is formed in the operation plate 105.

The front ends of the forward wire 107 and the reverse wire 108 are connected to the two corners of the upper portion of the operation plate 105, respectively, and the rear ends of the wires 107, 108 are connected to the transmission portion 109 having a forward / reverse switching function. And is interlockingly connected to the operation receiving portion 110 of the vehicle.

The proximal end of the forward / reverse switching lever 39 is substantially L
Bends into a V-shape, and the boss 111 at the tip is fixed,
The boss 111 is inserted between a bifurcated lever support 112 protruding from the center of the upper side of the operation plate 105, and a pivot bolt 113 is inserted through the lever support 112 and the boss 111 in common.
A forward / reverse switching lever 39 is connected so as to be tiltable left and right, and a detent rod 114 having a substantially L-shape in front view is continuously provided on the upper surface of the proximal end of the forward / reverse switching lever 39. Spring hooks protruding from the middle of 114 and the bearing 103
With a tension spring 116 interposed between
The distal end of the lever 114 is pressed against the edge of a detent plate 117 protruding from the outer peripheral surface of the handle shaft case 102 so that the operating position of the forward / reverse switching lever 39 is maintained.

On the other hand, the base end of a return arm 118 having a substantially L-shape in side view is fixed to the brake shaft 45, and the lower end of a return link 119 is pivotally attached to the distal end of the return arm 118. An elongated hole 120 extending substantially vertically is formed in the middle of the return link 119, and a guide pin 122 projecting from the elongated hole 120 on the outer periphery of the handle shaft case 102 via an outer receiving member 121. And by operating the brake pedal 37, the posture of the return link 119 when the return link 119 operates in the vertical direction is held substantially vertically.

A roller 124 is rotatably connected to the upper end of the return link 119 via a roller pin 123. The roller 124 is inserted into the operation hole 106 of the operation plate 105, and the brake is applied. When the return link 119 operates downward by the braking operation of the pedal 37, the forward / reverse switching lever 39
Is in a position other than the neutral position, since the operation plate 105 is deviated to the front or rear and is inclined, the roller 124 rolls on any inclined edge of the inverted triangular operation hole 106. That is, since the roller 124 is supported by the return link 119 which operates substantially vertically, the operation plate 105 returns to the neutral position by the reaction force of the rolling, and moves forward and backward connected to the operation plate 105. When the switching lever 39 returns to the neutral position, the forward / backward moving wires 107 and 108 return to the neutral position, and the transmission 109 is in the neutral state, and the traveling drive is stopped.

Also, at the corner below the working hole 106,
A position regulating concave portion 125 having a width substantially equal to the diameter of the roller 124 and extending downward is formed, and the roller 124 is inserted into the position restricting concave portion 125, thereby improving the positional accuracy of the neutral position return. ing.

The operating plate 105 and the operation receiving portion 110 of the speed change portion 109 can be connected to each other by a push-pull actuable wire or rod. In this case, the operating plate 105
It is only necessary to link only one corner to the operation receiver 110.

As described above, the forward / reverse switching lever 39 and the transmission 109 can be brought into the neutral state in conjunction with the braking operation of the brake pedal 37. Therefore, even if the braking operation is stopped, The safety can be improved without the aircraft moving suddenly.

From the above state, the forward / reverse switching lever
By operating 39 again, you can run normally.

Further, since the neutral position return mechanism 101 is disposed in the handle column 35, mud or the like does not adhere thereto, so that operation failure and malfunction can be prevented.

[0053]

According to the present invention, the following effects can be obtained.

According to the first aspect of the present invention, various working units are connected to the rear of the self-propelled traveling unit via an elevating mechanism, and an input shaft provided in the various working units is mounted on an engine mounted on the traveling unit. In a small-sized riding work machine interlocked via a PTO shaft, the power transmission from the engine to the PTO shaft is cut off in conjunction with the braking operation of the traveling unit, so that the operator can brake the vehicle in an emergency. When the braking operation is performed, the operation of various working units is stopped instantaneously, and the safety of the operator can be secured.
When the transmission of power to the PTO shaft is cut off in conjunction with the brake braking operation, the PTO clutch operating means is configured to return slowly, so that the PTO clutch operating means hits the operator and causes injury or incorrect operation due to this shock. Can be prevented, and the safety can be further improved.

According to the second aspect of the present invention, the PTO clutch is used to connect and disconnect the power transmission from the output shaft of the engine to the PTO shaft while the brake operation means is interlockedly connected to the brake device provided in the traveling section. The clutch operating means is interlockingly connected, and the PTO clutch operating means and the brake operating means are interlockingly connected via a clutch forcible disconnection mechanism. PT
In conjunction with the O-clutch disconnection operation, the power transmission to the PTO shaft is disconnected during the brake braking operation.
An interlocking operation canceling mechanism for canceling the interlocking operation between the PTO clutch operating unit and the PTO clutch in interlocking with the brake braking operation is interposed between the TO clutch operating unit and the PTO clutch. At the same time as the power transmission to the PTO shaft is cut off, the interlocking operation between the PTO clutch operating means and the PTO clutch is released, and the PTO clutch operating means is returned slowly. A clutch disengagement operation can be performed, and further, a sudden return of the PTO clutch operation means can be prevented, and safety can be ensured and manufacturing costs can be reduced.

According to the third aspect of the present invention, the traveling unit includes a transmission unit that switches between forward and backward driving directions by operating a forward / reverse switching lever, and the transmission unit operates in conjunction with a brake braking operation of the traveling unit. And the above-mentioned forward / reverse switching lever is provided with a neutral position return mechanism for returning to the neutral state, so that when the braking operation is performed, the transmission unit and the forward / backward switching lever automatically become neutral, and the forward / backward switching lever is Even without operation, the danger of the aircraft starting to move as soon as the braking operation is stopped can be prevented, and safety can be improved.

According to the fourth aspect of the present invention, the neutral position return mechanism is provided with an operation plate having a substantially triangular operation hole formed at the base end of the forward / reverse switching lever, and the operation plate is connected to the transmission unit. And a roller that operates substantially linearly in conjunction with the braking operation of the brake pedal is inserted into the operating hole so that the roller is positioned at one corner of the operating hole during the braking operation. By tilting the operation plate, the forward / reverse switching lever and the transmission unit are returned to the neutral state,
Even with a simple structure, even if the transmission section and the forward / reverse switching lever are in either forward or backward movement, they can be returned to the neutral state in conjunction with the braking operation.

According to the fifth aspect of the present invention, the neutral position return mechanism is disposed in the handle column erected on the upper surface of the floor of the traveling section, thereby preventing operation failure or malfunction due to adhesion of mud or the like. be able to.

[Brief description of the drawings]

FIG. 1 is a side view of a small riding work machine according to the present invention.

FIG. 2 is a side view of a PTO clutch operation lever (power transmission disconnected state).

FIG. 3 is an explanatory plan view of the PTO clutch operation lever.

FIG. 4 is a side view operation explanatory diagram of a clutch forced disconnection mechanism (power transmission connection state).

FIG. 5 is an explanatory side view of the clutch forcible disconnection mechanism (initial state of power transmission disconnection).

FIG. 6 is a side view of a neutral position return mechanism.

FIG. 7 is an enlarged side view of the neutral position return mechanism.

FIG. 8 is a front view of the neutral position return mechanism.

[Explanation of symbols]

A Small riding work machine B Running part C Tilling part (various working parts) E Engine 1 Elevating mechanism 22 PTO shaft 23 PTO clutch 24 Input shaft 25 Output shaft 34 Floor 35 Handle column 37 Brake pedal (brake operating means) 39 Forward / reverse switching Lever 42 PTO clutch operation lever (PTO clutch operation means) 49 Clutch forced disconnection mechanism 50 Interlocking operation release mechanism 101 Neutral position return mechanism 105 Operation plate 106 Operation hole 109 Transmission unit 110 Operation receiving unit 124 Roller

Claims (5)

[Claims] A working unit is connected via a lifting mechanism (1) to the rear of a self-propelled traveling unit (B).
The input shaft (2
4) is a small riding work machine linked with PTO shaft (22)
In (A), the engine is linked with the braking operation of the traveling section (B).
(E) to cut off the power transmission from the PTO shaft (22)
A small riding work machine characterized in that the PTO clutch operating means is returned slowly when power transmission to the PTO shaft (22) is interrupted in conjunction with the brake braking operation. 2. A brake device provided in the traveling portion (B) is connected to a brake operating means in an interlocking manner, while a power transmission from an output shaft (25) of the engine (E) to a PTO shaft (22) is connected / disconnected. The PTO clutch operating means is interlocked with the PTO clutch (23) to be operated, and the PTO clutch operating means and the brake operating means are interlockingly connected via a clutch forced disconnection mechanism (49), thereby forcibly disengaging the clutch (49). The brake operation of the brake operation means and the PT of the PTO clutch operation means
The power transmission to the PTO shaft (22) is cut off during the brake braking operation in conjunction with the O clutch disengagement operation, and the PTO clutch operating means and the PTO clutch (2
Between 3) and PTO in conjunction with the brake operation
An interlocking operation canceling mechanism (50) for canceling the interlocking operation between the clutch operating means and the PTO clutch (23) is interposed, so that the power transmission to the PTO shaft (22) is cut off by the brake braking operation and the PTO clutch operation is performed simultaneously. 2. A small riding work machine according to claim 1, wherein the interlocking operation between the means and the PTO clutch (23) is released and the PTO clutch operating means is returned slowly. The traveling section (B) includes a transmission section (109) for switching between forward and backward driving directions by operating a forward / backward switching lever (39), and interlocked with a brake braking operation of the traveling section (B). And a neutral position returning mechanism (101) for returning the transmission portion (109) and the forward / reverse switching lever (39) to a neutral state. The neutral position return mechanism (101) is provided with an operating plate (105) having a substantially triangular operating hole (106) formed at the base end of a forward / reverse switching lever (39). The plate (105) is interlockingly connected to the operation receiving portion of the speed change portion (109), and the roller (124) that operates substantially linearly in the operation hole (106) in conjunction with the braking operation of the brake pedal (37). When the braking operation is performed, the roller (124) tilts the operation plate (105) so as to be positioned at one corner of the operation hole (106), whereby the forward / reverse switching lever (39) and the transmission unit (109) are rotated. 4. The small-sized riding work machine according to claim 3, wherein the vehicle is returned to a neutral state. 5. A traveling unit for moving the neutral position return mechanism (101)
5. The small-sized riding work machine according to claim 3, wherein the small-sized riding work machine is disposed in a handle column (35) erected on the upper surface of the floor (34) of (B).