Walking type work machine

Abstract

To provide a walking type work machine that facilitates steering in turning and steering in straight advancement after turning, and simplifies operations.SOLUTION: A walking type work machine includes: a first operation mechanism B1 that is operated from a first state to a second state in turning, operated from the second state to the first state in straight advancement, and transmits received operations to a device A to be operated; a second operation mechanism B2 that receives an increasing operation and a decreasing operation of an engine speed, and transmits the operations to an engine 11; an interlocking mechanism C that interlocks the first operation mechanism B1 and the second operation mechanism B2, changes the second operation mechanism B2 to a state in which the decreasing operation is made in response to the fact that the first operation mechanism B1 is operated to the second state, and changes the second operation mechanism B2 to a state in which the increasing operation is made in response to the fact that the first operation mechanism B1 is operated to the first state; and an adjusting mechanism D that delays the change of the second operation mechanism B2 to the state in which the increasing operation is made when changing the second operation mechanism B2 to the state in which the increasing operation is made.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a walk-behind working machine. [Background technology]

[0002] Patent Document 1 discloses a walk-behind cultivator. An operator holds a steering handle to operate the walk-behind cultivator and walks with the moving walk-behind cultivator. A work clutch lever for turning the work clutch on and off is provided on the right side of the steering handle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-4843 A Summary of the Invention [Problem to be solved by the invention]

[0004] When a walk-behind cultivator is used to perform agricultural work in a field, it alternates between moving in a straight line and turning. For example, an operator performs tilling work while moving the walk-behind cultivator in a straight line parallel to the long side of the field. When the operator reaches the edge of the field, he turns the walk-behind cultivator to work on the next furrow. At that time, the operator operates the work clutch lever to disengage the work clutch and stop the cultivator. After completing the turn, the operator operates the work clutch lever to turn on the work clutch and drive the cultivator in order to perform tilling work while moving in a straight line.

[0005] When cultivating while moving in a straight line, the engine RPM is high to increase output. This means that the travel speed is also high. On the other hand, when turning, it is easier to steer at a slow travel speed. The engine RPM can be controlled with the throttle lever. However, it is cumbersome to operate both the work clutch lever and the throttle lever when turning. The same is true when moving straight after finishing a turn. In this respect, there is room for improvement in conventional walk-behind cultivators.

[0006] An object of the present invention is to provide a walk-behind working machine which is easy to steer when turning and when moving straight after turning, and which has simplified operation. [Means for solving the problem]

[0007] As a means for solving the above-mentioned problems, the walk-behind working machine of the present invention comprises: The vehicle includes an engine, an operated device, a first operating mechanism that is operated from a first state to a second state when turning and mechanically transmits the accepted operation to the operated device, and that is operated from the second state to the first state when going straight and mechanically transmits the accepted operation to the operated device, a second operating mechanism that accepts operations to increase and decrease the engine speed and mechanically transmits the accepted operation to the engine, a linkage mechanism that mechanically links the first operating mechanism and the second operating mechanism, and an adjustment mechanism that acts on the second operating mechanism, wherein the linkage mechanism changes the second operating mechanism to the lowered state in response to the first operating mechanism being operated to the second state, and changes the second operating mechanism to the raised state in response to the first operating mechanism being operated to the first state, and the adjustment mechanism delays the change of the second operating mechanism to the raised state when the linkage mechanism changes the second operating mechanism to the raised state.

[0008] According to the above feature, when the first operating mechanism is operated to the second state, the operation is transmitted to the operated device and the second operating mechanism is changed to a lowered state, so that the engine speed decreases. Therefore, there is no need to operate the engine speed when turning, and the engine speed decreases, making it easier to turn. In other words, steering when turning is easier and the operation is simplified. When the first operating mechanism is operated to the first state, the operation is transmitted to the operated device, and the second operating mechanism is changed to the raised state, so that the engine speed increases. Since the change of the second operating mechanism to the raised state is delayed, the engine speed increases gradually. Therefore, there is no need to perform an operation to restore the engine speed when going straight after turning, and the engine speed automatically increases gradually, so that the driving speed does not increase immediately but gradually. In other words, steering when going straight after turning is made easier and the operation is simplified.

[0009] Furthermore, according to the above features, the first operating mechanism and the second operating mechanism are mechanically linked, eliminating the need for expensive electronic components, which is preferable because it suppresses an increase in the manufacturing cost of the walk-behind work machine while reliably achieving a reduction in engine speed during turning.

[0010] In the present invention, The adjustment mechanism is preferably a damper linked to the second operating mechanism.

[0011] According to the above features, the change of the second operating mechanism to the raised state can be delayed simply by linking a damper to the second operating mechanism, so that the engine speed automatically and gradually increases when going straight after a turn, gradually increasing the driving speed, while still being inexpensive.

[0012] In the present invention, The damper is preferably a rotary damper.

[0013] According to the above features, the change of the second operating mechanism to the raised state can be delayed simply by linking the rotary damper to the second operating mechanism, so that the engine speed automatically increases gradually when going straight after a turn, gradually increasing the driving speed, while requiring a compact adjustment structure and being inexpensive.

[0014] In the present invention, It is preferable that the first operating mechanism comprises a first manual operating tool that is manually operated and a first transmission mechanism that transmits the operation accepted by the first manual operating tool to the operated device, and the second operating mechanism comprises a second manual operating tool that is manually operated and a second transmission mechanism that transmits the operation accepted by the second manual operating tool to the engine, and the interlocking mechanism mechanically interlocks the first manual operating tool and the second transmission mechanism.

[0015] According to the above-mentioned features, the first manual operating device and the second transmission mechanism are mechanically linked, so that a decrease in engine speed when turning is reliably achieved, and an increase in engine speed when traveling straight is reliably achieved.

[0016] In the present invention, the second transmission mechanism is an operating wire having an inner wire and an outer wire, The interlocking mechanism preferably includes an outer receiving member that slidably holds an end of the outer wire, and an operating tool interlocking mechanism that interlocks and connects the outer receiving member to the first manual operating tool.

[0017] According to the above configuration, in the second operation mechanism, the outer receiving member is slid to operate the outer wire to the bending side or the extending side and the inner wire is extended or retracted to increase or decrease the engine speed, so that the increase or decrease in the engine speed in response to the operation of the first operation mechanism to the second state or the first state is performed without changing the operation position of the second manual operation device. In other words, when traveling straight after turning, the engine speed is increased to the same speed as the speed before the operation to decrease the engine speed during turning, and when traveling straight after turning, the vehicle can perform work traveling at the same traveling speed as the traveling speed before turning.

[0018] In the present invention, It is preferable that the second transmission mechanism is an operating wire having an inner wire and an outer wire, the interlocking mechanism includes an outer support member that slidably holds the end of the outer wire, and an operating tool interlocking mechanism that interlocks and connects the outer support member to the first manual operating tool, and the adjustment mechanism is a damper that acts on the outer support member.

[0019] According to the above configuration, in the second operation mechanism, the outer receiving member is slid, the outer wire is operated to the bending side or the extending side, and the inner wire is paid out or retracted, thereby increasing or decreasing the engine speed. As a result, the engine speed is increased or decreased in response to the first operation mechanism being operated to the second state or the first state without changing the operating position of the second manual operation device. In other words, when traveling straight after turning, the engine speed is increased to the same speed as the speed before the engine speed was decreased during the turn, and after the turn, the vehicle can perform work traveling at the same traveling speed as before the turn without any special operation to increase the engine speed. Furthermore, by simply applying a damper to the outer support member, the change of the second operating mechanism to the raised state can be delayed, so that the engine speed can be automatically and gradually increased when driving straight after a turn, and the driving speed can be made to be the same as the driving speed before the turn, all at an inexpensive cost.

[0020] In the present invention, It is preferable that the vehicle is equipped with a work clutch as the operated device that turns on and off the power transmission to a PTO shaft or a working device, and a main clutch that turns on and off the power transmission from the engine to the work clutch, and that the work clutch is configured to turn on the power transmission in response to the first operating mechanism accepting an operation to the first state, and to turn off the power transmission in response to the first operating mechanism accepting an operation to the second state.

[0021] According to the above features, the operation of the walk-behind working machine is simplified because the engine speed can be decreased or increased, and the work clutch can be turned on and off by operating the manual operation tool. In addition, turning can be easily performed by decreasing the engine speed and stopping the working device (or the PTO shaft). Work can be performed efficiently by increasing the engine speed and driving the working device (or the PTO shaft).

[0022] In the present invention, It is preferable that the vehicle is provided with left and right traveling devices and a differential mechanism as the operated device capable of regulating the differential between the left and right traveling devices, and that the differential mechanism is configured to enter a state in which the differential is restricted in response to the first operating mechanism accepting an operation to the first state, and to enter a state in which the differential is not restricted in response to the first operating mechanism accepting an operation to the second state.

[0023] According to the above features, the operation of the walk-behind working machine can be simplified since the engine speed can be decreased or increased, and the differential restriction of the differential mechanism can be restricted or released by operating the manual operating tool. In addition, the engine speed can be decreased and the differential restriction can be released to facilitate turning. The engine speed can be increased and the differential restriction can be restricted to facilitate straight-line work travel, allowing work to be performed efficiently.

[0024] In the present invention, It is preferable that the vehicle is provided with left and right traveling devices and a side clutch as the operated device that turns on and off the power transmission to the left and right traveling devices, and that the side clutch is configured to turn on the power transmission in response to the first operating mechanism accepting an operation to the first state, and to turn off the power transmission in response to the first operating mechanism accepting an operation to the second state.

[0025] According to the above features, the operation of the walk-behind work machine is simplified because the engine speed can be controlled to decrease or increase, and the side clutch can be turned on and off, by operating the manual operating tool. In addition, by lowering the engine speed and disengaging the side clutch, it becomes easier to turn, and by increasing the engine speed and engaging the side clutch, it becomes easier to travel straight for work, allowing work to be done more efficiently.

[0026] In the present invention, It is preferable that the vehicle is provided with one first operating mechanism, a working clutch as the operated device that turns on and off the power transmission to a PTO shaft or a working device, a main clutch that turns on and off the power transmission from the engine to the working clutch, left and right traveling devices, and a differential mechanism as the operated device that can regulate the differential between the left and right traveling devices, wherein the working clutch is configured to turn on the power transmission in response to the first operating mechanism accepting an operation to the first state, and to turn off the power transmission in response to the first operating mechanism accepting an operation to the second state, and the differential mechanism is configured to enter a state in which the differential is restricted in response to the first operating mechanism accepting an operation to the first state, and to enter a state in which the differential is not restricted in response to the first operating mechanism accepting an operation to the second state.

[0027] According to the above features, the operation of the walk-behind working machine can be greatly simplified, since the engine speed reduction, lift control, work clutch on / off operation, differential restriction of the differential mechanism, and release of the differential restriction can all be achieved by operating a single manual operating tool. In addition, turning can be easily performed by reducing the engine speed, stopping the working equipment (or PTO shaft), and releasing the differential restriction. Straight-line work travel can be easily performed by increasing the engine speed, driving the working equipment (or PTO shaft), and differential restriction, and work can be performed efficiently. [Brief description of the drawings]

[0028] [Figure 1] FIG. 2 is a left side view showing the entire walk-behind cultivator. [Diagram 2] FIG. 2 is a plan view showing the entire walk-behind cultivator. [Diagram 3] FIG. 2 is a diagram showing a power transmission system and an operating system. [Figure 4] 13 is a diagram showing the interlocking mechanism and the rotary damper when the swivel lever is in the OFF position. FIG. [Diagram 5] FIG. 13 is a diagram showing the interlocking mechanism and the rotary damper when the swivel lever is in the ON position. [Figure 6]13A and 13B are diagrams illustrating the action of the rotary damper when the turning lever is operated to the OFF position. [Figure 7] FIG. 11 is a diagram showing a power transmission system and an operating system according to a second embodiment. [Figure 8] FIG. 13 is a diagram showing a power transmission system and an operating system according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] [First embodiment] Hereinafter, an embodiment of a walk-behind cultivator, which is an example of a walk-behind working machine according to the present invention, will be described with reference to the drawings. Note that the present invention is not limited to the following embodiment, and various modifications are possible without departing from the gist of the present invention.

[0030] In addition, unless otherwise specified, the front-rear and left-right directions in the explanation of this embodiment are described as follows: In other words, the forward traveling direction when the walk-behind cultivator is traveling for work (see arrow FR in Figs. 1 and 2) is "forward", the backward traveling direction (see arrow BK in Figs. 1 and 2) is "rear", the direction corresponding to the right side based on the forward posture in the front-rear direction (see arrow RH in Fig. 2) is "right", and similarly the direction corresponding to the left side (see arrow LH in Fig. 2) is "left".

[0031] [Overall structure] As shown in FIGS. 1 and 2, the traveling body of the walk-behind cultivator has an engine 11, which serves as a drive source, mounted on an engine frame 10 that constitutes a part of the body frame 1.

[0032] A transmission case 2, which constitutes the vehicle frame 1 together with the engine frame 10, is connected integrally to the rear side of the engine frame 10. The engine 11 and the transmission case 2 are connected together via a belt transmission mechanism 12 so as to be capable of transmitting power.

[0033] The transmission case 2 is formed in a bifurcated shape, including a front case 2A extending downward and a rear case 2B extending diagonally downward and rearward.

[0034] Left and right traveling devices 13 are supported via axles 20 at the lower part of the front case 2A. In this embodiment, the running device 13 is a wheel. The running device 13 may be a device of another form, such as a crawler running device.

[0035] A working device 14 is supported on the rear case 2B via a drive shaft 21. In this embodiment, the working device 14 is a rotary tilling device. The working device 14 may be another type of device, such as a ridge maker or a seed sowing machine.

[0036] Power from the engine 11 is transmitted to a gear transmission mechanism (not shown) inside the transmission case 2 via a belt transmission mechanism 12. The belt transmission mechanism 12 is configured so that the power transmission can be turned on and off by a clutch operating arm 12a. The belt transmission mechanism 12 and the clutch operating arm 12a form a main clutch 31 (FIG. 3) that connects and disconnects the power transmission to the traveling drive system and the working drive system.

[0037] A working clutch 32, a running clutch 33, and a differential mechanism 34 are provided inside the transmission case 2 (see FIG. 3). Power from the main clutch 31 is branched and transmitted to the working clutch 32 and the running clutch 33.

[0038] The work clutch 32 turns on and off the power transmission to the working device 14. The travel clutch 33 turns on and off the power transmission to the travel device 13 via a differential mechanism 34. The differential mechanism 34 can regulate the differential between the left and right travel devices 13. The work clutch 32 and the differential mechanism 34 are one example of an operated device A described later.

[0039] A main speed change lever 15 extends diagonally upward and rearward from the top of the transmission case 2. By operating this main speed change lever 15, the gear shift operation and forward / reverse operation of the traveling device 13, as well as the forward / reverse operation of the working device 14 can be performed.

[0040] A control handle 16 extends from the rear of the transmission case 2 toward the rear of the aircraft. A turning lever 17, a stop switch 18, and a throttle lever 19 are disposed on the right side of the steering handle 16. A clutch lever 3 is disposed on the rear end side of the steering handle 16.

[0041] The turning lever 17 is for operating the work clutch 32 and the differential mechanism 34, which are the operated device A, and is a part of a first operating mechanism B1, which will be described later, and is an example of a first manual operating tool J1.

[0042] When the turning lever 17 is in the disengaged position (first state), the working clutch 32 is in a state in which it transmits power (clutch engaged), and the differential mechanism 34 is in a state in which it restricts the differential of the traveling device 13 (diff-lock engaged).

[0043] When the swing lever 17 is in the engaged position (second state), the working clutch 32 is in a state in which it does not transmit power (clutch disengaged), and the differential mechanism 34 is in a state in which it does not restrict the differential motion of the traveling device 13 (diff-lock disengaged).

[0044] A stop switch 18 is wired to the control system of the engine 11 for use in stopping the engine 11 .

[0045] The throttle lever 19 is used to control the rotation speed of the engine 11, is a part of a second operation mechanism B2 described later, and is an example of a second manual operation tool J2. In this embodiment, the throttle lever 19 is configured to be held in the operating position even if the operator releases his / her hand. The throttle lever 19 may be configured to automatically return to the initial position when the operator releases his / her hand.

[0046] There is provided a main clutch 31 that switches on and off the power transmission from the engine 11 to a working clutch 32 and a traveling clutch 33. The clutch lever 3 is connected to the main clutch 31 for switching on and off the main clutch 31.

[0047] In the walk-behind cultivator configured as above, the operator operates the walk-behind cultivator by holding the steering handle 16, and walks together with the moving walk-behind cultivator. Turning is performed by the operator turning the steering handle 16 to the left or right to change the direction in which the walk-behind cultivator travels.

[0048] [Power transmission system and operating system] FIG. 3 shows a power transmission system and an operating system of the walk-behind type cultivator of this embodiment.

[0049] The power transmission system will now be described. Power is transmitted from the engine 11 to the working device 14 via a main clutch 31 and a working clutch 32. Power is transmitted from the engine 11 to the traveling device 13 via the main clutch 31, a traveling clutch 33, and a differential mechanism 34.

[0050] The operation system will be described. As shown in Fig. 3, the walk-behind cultivator of this embodiment includes a first operation mechanism B1 linked to the operated device A, a second operation mechanism B2 linked to the engine 11, an interlocking mechanism C that mechanically interlocks the first operation mechanism B1 and the second operation mechanism B2, and an adjustment mechanism D that acts on the second operation mechanism B2.

[0051] The first operating mechanism B1 is configured to be operated from a first state to a second state during turning and to transmit the accepted operation to the operated device A, and to be operated from the second state to the first state during straight driving and to transmit the accepted operation to the operated device A. As shown in Fig. 3, the first operating mechanism B1 includes a first manual operation device J1 that is manually operated, and a first transmission mechanism K1 that transmits the operation accepted by the first manual operation device J1 to the operated device A.

[0052] The second operating mechanism B2 is configured to receive an operation to increase and decrease the rotation speed of the engine 11 and to mechanically transmit the received operation to the engine 11. As shown in FIG. 3, the second operating mechanism B2 includes a second manual operation device J2 that is manually operated, and a second transmission mechanism K2 that transmits the operation received by the second manual operation device J2 to the engine 11.

[0053] The interlocking mechanism C is configured to change the second operating mechanism B2 to a lowered state in response to the first operating mechanism B1 being operated to the second state, and to change the second operating mechanism B2 to an elevated state in response to the first operating mechanism B1 being operated to the first state. As shown in Fig. 3, the interlocking mechanism C mechanically interlocks the first manual operating device J1 and the second transmission mechanism K2.

[0054] A specific description will be given with reference to Fig. 3. In this embodiment, the first manual operation tool J1 of the first operation mechanism B1 is a turning lever 17. The turning lever 17 is operated by the operator from the off position (first state) to the in position (second state) when the walk-behind cultivator turns, and is operated by the operator from the in position (second state) to the off position (first state) when the walk-behind cultivator moves straight ahead.

[0055] A first operation wire 17a, a second operation wire 17b, and a third operation wire 17c are provided to transmit the operation received by the turning lever 17.

[0056] The first operation wire 17a and the second operation wire 17b are the first transmission mechanism K1 of the first operation mechanism B1. In this embodiment, the "operation wire" is an operation transmission mechanism in which an inner wire advances and retreats inside a fixed outer wire to transmit an operation.

[0057] The first operating wire 17a mechanically transmits the operation received by the swing lever 17 to the work clutch 32. The work clutch 32 is one of the operated devices A. When the swing lever 17 is operated from the OFF position to the ON position, the work clutch 32 changes from a state in which power is transmitted to a state in which power is not transmitted (change in operating state). This causes the working device 14 to stop operating. When the swing lever 17 is operated from the ON position to the OFF position, the work clutch 32 changes from a state in which power is not transmitted to a state in which power is transmitted (change in operating state). This causes the working device 14 to operate.

[0058] The second operating wire 17b mechanically transmits the operation received by the swivel lever 17 to the differential mechanism 34. The differential mechanism 34 is one of the operated devices A. When the swivel lever 17 is operated from the OFF position to the ON position, the differential mechanism 34 changes from a state in which the differential between the left and right traveling devices 13 is restricted to a state in which the differential is not restricted (change in operating state). This allows the left and right traveling devices 13 to move more easily, making it easier for the operator to turn the walk-behind cultivator. When the swivel lever 17 is operated from the ON position to the OFF position, the differential mechanism 34 changes from a state in which the differential between the left and right traveling devices 13 is not restricted to a state in which the differential is restricted (change in operating state). This restricts the differential between the left and right traveling devices 13, making it easier for the operator to move the walk-behind cultivator in a straight line.

[0059] The third operation wire 17c transmits to the second operation mechanism B2 that the first operation mechanism B1 has been operated to the second state, and transmits to the second operation mechanism B2 that the first operation mechanism B1 has been operated to the first state. That is, the third operation wire 17c constitutes a part of the interlocking mechanism C. The third operation wire 17c will be described in detail later.

[0060] In this embodiment, the second manual operation tool J2 of the second operation mechanism B2 is a throttle lever 19. The throttle lever 19 receives an operation for increasing and decreasing the rotation speed of the engine 11.

[0061] A fourth operation wire 19a is provided to transmit the operation received by the throttle lever 19 to the engine 11. The fourth operation wire 19a is the second transmission mechanism K2 of the second operation mechanism B2. The fourth operation wire 19a extends from the throttle lever 19 through the interlocking mechanism C to the engine 11.

[0062] [Interlocking mechanism] The interlocking mechanism C will be described with reference to Figures 4 and 5. The interlocking mechanism C is configured to mechanically interlock the first operating mechanism B1 and the second operating mechanism B2. In the following description of the interlocking mechanism C, the positional relationship and movement direction of members may be indicated by the directions of arrows X1 and X2 shown in the figures.

[0063] 4 and 5, in this embodiment, in addition to the third operation wire 17c, the interlocking mechanism C is provided with the outer receiving member 6, the third operation wire 17c as an operation device interlocking mechanism that interlocks the outer receiving member 6 with the first manual operation device J1 (the turning lever 17), and a return spring 7 that returns the outer receiving member 6. The interlocking mechanism C is configured to move the outer receiving member 6 in response to the first operation mechanism B1 being operated to the second state, thereby changing the second operation mechanism B2 to a state in which it has been lowered, and to move the outer receiving member 6 in response to the first operation mechanism B1 being operated to the first state, thereby changing the second operation mechanism B2 to a state in which it has been raised.

[0064] A more detailed description will be given. As shown in Figs. 4 and 5, a casing 40 is provided to house the main parts of the interlocking mechanism C therein. The outer support member 6 is slidably held on a guide rail portion 41 provided on the casing 40. The return spring 7 is provided between the outer support member 6 and an end portion 40a on the X2 side of the casing 40. The outer support member 6 is slidably biased by the return spring 7 to a position where it is positioned by abutting against an end portion 40b on the X1 side of the casing 40.

[0065] An end of the outer wire of the third operation wire 17c is fixed to an end 40a on the X2 side of the casing 40. An inner wire 42 of the third operation wire 17c is connected to the outer support member 6 inside the casing 40. The inner wire 42 is connected to the outer support member 6 by passing the inner wire 42 through a connecting hole in the outer support member 6 and providing a stopper portion 43 with a larger diameter than the connecting hole at the end of the inner wire 42 protruding from the connecting hole.

[0066] The outer wire of the fourth operation wire 19a is divided into a lever-side outer wire 44 connected to the throttle lever 19 and an engine-side outer wire 45 connected to the engine 11. An end of the engine-side outer wire 45 is fixed to an end 40a on the X2 side of the casing 40. The lever-side outer wire 44 is inserted into the casing 40 through a through-hole 40c provided at the end on the X1 side of the casing 40, and an end 44a of the lever-side outer wire 44 is held by the outer support member 6. More specifically, the end 44a of the lever-side outer wire 44 is held by the outer support member 6 in a state in which it can be slid by the outer support member 6.

[0067] FIG. 4 shows the interlocking mechanism C when the turning lever 17 is in the off position (first state). As shown in FIG. 4, when the turning lever 17 is in the off position (first state), the inner wire 42 of the third operation wire 17c is in a loose state, and the outer support member 6 is in a position in contact with the end 40b on the X1 side of the casing 40 due to the sliding force of the return spring 7. Since the outer support member 6 is positioned at the end 40b on the X1 side of the casing 40, the end 44a of the lever side outer wire 44 is located on the X1 side of the casing 40, and the lever side outer wire 44 is in a state in which it is greatly bent. Since the lever side outer wire 44 is greatly bent, the inner wire 46 of the fourth operation wire 19a is in a state in which it is pulled, and the engine 11 is in a state in which it is pulled and operated to rise by the pulling of the inner wire 46. That is, the accelerator operation part 11a of the engine 11 is in a first operation position H set by the throttle lever 19.

[0068] FIG. 5 shows the interlocking mechanism C when the turning lever 17 is in the ON position (second state). As shown in FIG. 5, when the turning lever 17 is operated from the OFF position (first state) to the ON position (second state), the inner wire 42 of the third operation wire 17c is pulled, and the outer support member 6 is slid toward the X2 side against the return spring 7 by the pulling of the inner wire 42. By the sliding of the outer support member 6 toward the X2 side, the end portion 44a of the lever side outer wire 44 of the fourth operation wire 19a is transferred toward the X2 side. By the transfer of the end portion 44a of the lever side outer wire 44 toward the X2 side, the bending of the lever side outer wire 44 becomes smaller. By the bending of the lever side outer wire 44 becoming smaller, the inner wire 46 is loosened and the engine 11 is lowered. That is, the accelerator operating unit 11a of the engine 11 is operated to a second operating position L which is slower than the first operating position H set by the throttle lever 19. The accelerator operating unit 11a is operated to the second operating position L by a biasing force applied to the accelerator operating unit 11a. As the bending of the lever side outer wire 44 becomes smaller, the inner wire 46 is loosened and the engine 11 is lowered. Therefore, even if the engine 11 is lowered, the operating position of the throttle lever 19 does not change, and the throttle lever 19 remains in the operating position which sets the accelerator operating unit 11a to the first operating position H.

[0069] When the turning lever 17 is operated from the ON position (second state) to the OFF position (first state), as shown in Fig. 4, the inner wire 42 of the third operation wire 17c is loosened and the outer receiving member 6 is operated to the X1 side by the return spring 7, the end portion 44a of the lever side outer wire 44 is moved to the X1 side and the bending of the lever side outer wire 44 increases, and the inner wire 46 of the fourth operation wire 19a is pulled and the engine 11 is operated to rise. In other words, the accelerator operation portion 11a of the engine 11 is operated to the first operation position H set by the throttle lever 19.

[0070] [Adjustment mechanism] The adjustment mechanism D is configured to delay the change of the second operation mechanism B2 to the raised state when the interlocking mechanism C changes the second operation mechanism B2 to the raised state. In this embodiment, the adjustment mechanism D is configured by a rotary damper interlocked with the second operation mechanism B2. In the following description, the rotary damper will be referred to as the rotary damper D.

[0071] Specifically, as shown in Fig. 4, the rotary damper D is held in a casing 40. An interlocking unit 47 that interlocks the rotary damper D with the second operating mechanism B2 is disposed inside the casing 40. The interlocking unit 47 is provided on a rotation shaft 48 of the rotary damper D, and is provided on the rotary damper D in a state in which it can swing around the rotation shaft 48 as a swing fulcrum. The interlocking unit 47 interlocks with the outer support member 6, thereby interlocking the rotary damper D with the second operating mechanism B2.

[0072] As shown in Figure 4, when the pivot lever 17 is in the off position (first state) and the outer support member 6 is positioned by abutting against the X1 side end 40b of the casing 40, the tip 47a of the interlocking portion 47 abuts against the end 6a of the outer support member 6.

[0073] When the turning lever 17 is operated from the OFF position (first state) to the ON position (second state) and the outer support member 6 slides toward the X2 side, the interlocking portion 47 swings in the first swing direction Z following the outer support member 6 due to the rotational force of the rotary damper D. As the outer support member 6 slides, the tip portion 47a of the interlocking portion 47 comes out of contact with the end portion 6a of the outer support member 6. As shown in Fig. 5, when the turning lever 17 reaches the ON position (second state), the tip portion 47a of the interlocking portion 47 comes into contact with the side portion 6b on the X1 side of the outer support member 6.

[0074] 6, when the turning lever 17 is operated from the ON position (second state) to the OFF position (first state) and the outer support member 6 slides toward the X1 side, the interlocking portion 47 is pushed by the outer support member 6 and swings in a second swing direction Y opposite to the first swing direction Z. When the turning lever 17 reaches the OFF position (first state), the interlocking portion 47 is in the state shown in FIG.

[0075] When the interlocking portion 47 swings in the second swing direction Y to rotate the rotating shaft 48, the rotary damper D generates a stronger braking torque than when the interlocking portion 47 swings in the first swing direction Z to rotate the rotating shaft 48. Due to the action of the rotary damper D on the outer support member 6, the outer support member 6 moves more slowly when moved to the X1 side by the return spring 7 than when moved to the X2 side by the pull of the inner wire 42. In other words, the rotary damper D delays the change of the second operating mechanism B2 to the raised state when the interlocking mechanism C changes the second operating mechanism B2 to the raised state.

[0076] When the walking-type cultivator has finished turning and the turning lever 17 is operated from the ON position (second state) to the OFF position (first state) to drive the walking-type cultivator straight, the engine 11 speed is automatically increased by the action of the interlocking mechanism C. This change in engine speed is performed by the action of the rotary damper D so that the engine speed is gradually increased, and the running speed does not increase immediately but gradually. The engine 11 speed is automatically increased to the speed set by the second operating mechanism B2 (throttle lever 19). As the rotary damper D, it is preferable to adopt a one-way rotary damper that rotates lightly when the interlocking part 47 swings in the first swing direction Z and generates a braking torque when the interlocking part 47 swings in the second swing direction Y. In this embodiment, a rotary damper is adopted, but it is possible to adopt a telescopic slide damper that is interlocked with the interlocking part 47 via a link mechanism.

[0077] [Another embodiment] The walk-behind cultivator of the embodiment described above is configured such that, by operating one first operating mechanism B1 (swivel lever 17), the operating states of two operated devices A (work clutch 32 and differential mechanism 34) change, and the second operating mechanism B2 (throttle lever 19) is changed to a lowered or raised state, and the rotation speed of the engine 11 decreases or increases, but this is not limited thereto. The walk-behind cultivator may be configured to have one first operating mechanism B1 corresponding to one operated device A. Specifically, the walk-behind cultivator may be equipped with an operating tool for operating the work clutch 32 and an operating tool for operating the differential mechanism 34. When the walk-behind cultivator is equipped with multiple first operating mechanisms B1, the interlocking mechanism C may be configured to change the second operating mechanism B2 to a lowered state in response to at least one first operating mechanism B1 receiving an operation to the second state. Furthermore, the interlocking mechanism C may be configured to change the second operating mechanism B2 to a lowered operating state in response to all of the first operating mechanisms B1 receiving an operation to the second state.

[0078] Second Embodiment A second embodiment of the present invention will be described with reference to FIG.

[0079] The walking type cultivator of this embodiment includes a PTO shaft 14a. Power from the engine 11 is transmitted to the PTO shaft 14a via a main clutch 31 and a working clutch 32. That is, the working clutch 32 turns on and off the power transmission to the PTO shaft 14a. The working device 14 is connected to the PTO shaft 14a.

[0080] Third Embodiment A third embodiment of the present invention will be described with reference to FIG.

[0081] The walk-behind cultivator of this embodiment is provided with a side clutch 35 instead of the differential mechanism 34. The side clutch 35 turns on and off the power transmission to the left and right traveling devices 13. More specifically, the side clutch 35 is configured to be able to independently turn on and off the power transmission from the engine 11 to each of the left and right traveling devices 13. The side clutch 35 is an example of an operated device A.

[0082] Left and right side clutch levers 36 are disposed on the left and right ends of the operation handle 16. The side clutch lever 36 is for operating a side clutch 35, which is an operated device A, and is an example of a first manual operation device J1.

[0083] A state in which the side clutch lever 36 is not operated is defined as an engaged position (first state). When the right (or left) side clutch lever 36 is in the engaged position, the side clutch 35 is in a state in which it transmits power to the right (or left) traveling device 13 (clutch engaged).

[0084] The state in which the side clutch lever 36 is operated is defined as a disengaged position (second state). When the right (or left) side clutch lever 36 is in the disengaged position, the side clutch 35 is in a state in which it does not transmit power to the right (or left) traveling device 13 (clutch disengaged).

[0085] The operation system will now be described. In this embodiment, the first manual operation tool J1 is a side clutch lever 36. Either the left or right side clutch lever 36 is operated by the operator from the on position (first state) to the off position (second state) when the walk-behind cultivator turns.

[0086] A fifth operation wire 36a and a sixth operation wire 36b that transmit the operation received by the side clutch lever 36 are provided.

[0087] The fifth operation wire 36a mechanically transmits the operation received by the side clutch lever 36 to the side clutch 35. The side clutch 35 is one of the operated devices A. When the right (or left) side clutch lever 36 is operated from the ON position to the OFF position, the side clutch 35 changes from a state in which it transmits power to the right (or left) traveling device 13 to a state in which it does not transmit power (change in operating state). Then, the right (or left) traveling device 13 is not driven and is in a state in which it can perform a driven operation. The fifth operation wire 36a is the first transmission mechanism K1. The side clutch lever 36 and the fifth operation wire 36a constitute the first operation mechanism B1. The side clutch 35 is configured to cut off the power transmission in response to the first operation mechanism B1 receiving the operation to the second state, and to turn on the power transmission in response to the first operation mechanism B1 receiving the operation to the first state.

[0088] The sixth operation wire 36b transmits to the second operation mechanism B2 that the side clutch lever 36 has been operated to the off position (second state) and that the side clutch lever 36 has been operated to the on position (first state).

[0089] The inner wire of the sixth operation wire 36b, like the inner wire 42 of the third operation wire 17c, extends inside the casing 40 of the interlocking mechanism C and is connected to the outer support member 6. Therefore, the outer support member 6 moves in the X1 direction or the X2 direction in response to operation of the side clutch lever 36, and moves the end portion 44a of the lever side outer wire 44 of the fourth operation wire 19a in the same manner as in the above-described embodiment.

[0090] Therefore, the interlocking mechanism C of the walk-behind cultivator of this embodiment, similar to the above-described embodiment, mechanically interlocks the first operating mechanism B1 (side clutch lever 36 and fifth operating wire 36a) and the second operating mechanism B2 (throttle lever 19 and fourth operating wire 19a), and is configured to change the second operating mechanism B2 to a lowered state in response to the first operating mechanism B1 being operated to the second state, and to change the second operating mechanism B2 to an raised state in response to the first operating mechanism B1 being operated to the first state.

[0091] Other Embodiments (1) In the above embodiment, the interlocking mechanism C mechanically interlocks the first manual operation device J1 and the second transmission mechanism K2. The objects interlocked by the interlocking mechanism C may be the first transmission mechanism K1 and the second manual operation device J2, the first manual operation device J1 and the second manual operation device J2, or the first transmission mechanism K1 and the second transmission mechanism K2.

[0092] (2) In the above embodiment, the adjustment mechanism D is configured by a rotary damper, but is not limited thereto. For example, an extendable slide damper can be adopted instead of the rotary damper. That is, the adjustment mechanism D may be configured by a slide damper that is linked to the second operation mechanism B2 via a link mechanism. In addition, various resistance applying devices such as a friction brake that switches to a non-acting state that does not act on the second operation mechanism B2 when the interlocking mechanism C changes the second operation mechanism B2 to a lowered state, and switches to an acting state that acts on the second operation mechanism B2 when the interlocking mechanism C changes the second operation mechanism B2 to a raised state, can be adopted as the adjustment mechanism instead of the damper. [Industrial Applicability]

[0093] The present invention is applicable to walk-behind working machines equipped with an engine, such as walk-behind cultivators, walk-behind rice transplanters, and walk-behind vegetable transplanters. [Explanation of symbols]

[0094] 6: Outer support member 11: Engine 13: Running gear 14: Working equipment 14a:PTO axis 17c: Third operating wire (operating tool interlocking mechanism) 19a: Fourth operating wire (operating wire) 31: Main clutch 32: Working clutch 34: Differential mechanism 35: Side clutch 44: Lever side outer wire (outer wire) 46: Inner wire A: Operated device B1: 1st operating mechanism B2:Second operating mechanism C: Interlocking mechanism D: Rotary damper (adjustment mechanism) J1: 1st human operating tool J2: 2nd human operating tool K1: First transmission mechanism K2: Second transmission mechanism

Claims

1. The engine, An operated device; a first operation mechanism that is operated from a first state to a second state during turning and mechanically transmits the received operation to the operated device, and that is operated from the second state to the first state during straight traveling and mechanically transmits the received operation to the operated device; a second operation mechanism that receives an operation to increase and decrease the rotation speed of the engine and mechanically transmits the received operation to the engine; an interlocking mechanism that mechanically interlocks the first operation mechanism and the second operation mechanism; an adjustment mechanism acting on the second operating mechanism; the interlocking mechanism changes the second operation mechanism to the lowered state in response to the first operation mechanism being operated to the second state, and changes the second operation mechanism to the raised state in response to the first operation mechanism being operated to the first state, The adjustment mechanism delays the change of the second operating mechanism to the raised state when the interlocking mechanism changes the second operating mechanism to the raised state.

2. 2. The walk-behind work machine according to claim 1, wherein the adjustment mechanism is a damper linked to the second operation mechanism.

3. 3. The walk-behind work machine according to claim 2, wherein the damper is a rotary damper.

4. The first operation mechanism includes a first manual operation tool that is manually operated, and a first transmission mechanism that transmits an operation received by the first manual operation tool to the operated device, The second operation mechanism includes a second manual operation tool that is manually operated, and a second transmission mechanism that transmits the operation received by the second manual operation tool to the engine, 2. The walk-behind work machine according to claim 1, wherein the interlocking mechanism mechanically interlocks the first manual operation tool and the second transmission mechanism.

5. the second transmission mechanism is an operating wire having an inner wire and an outer wire, The walk-behind working machine according to claim 4, wherein the interlocking mechanism comprises an outer support member that slidably holds an end of the outer wire, and an operating tool interlocking mechanism that interlocks the outer support member with the first manual operating tool.

6. the second transmission mechanism is an operating wire having an inner wire and an outer wire, The interlocking mechanism includes an outer receiving member that slidably holds an end of the outer wire, and an operating tool interlocking mechanism that interlocks the outer receiving member with the first operating tool, 5. The walk-behind work machine according to claim 4, wherein the adjustment mechanism is a damper that acts on the outer support member.

7. A working clutch as the operated device that turns on and off the power transmission to the PTO shaft or the working device; a main clutch that switches on and off the power transmission from the engine to the working clutch, 2. The walk-behind work machine according to claim 1, wherein the work clutch is configured to turn on power transmission in response to the first operating mechanism accepting an operation to the first state, and to turn off power transmission in response to the first operating mechanism accepting an operation to the second state.

8. The left and right running gear, A differential mechanism as the operated device is provided, the differential mechanism being capable of regulating the differential between the left and right traveling devices; 2. The walk-behind working machine according to claim 1, wherein the differential mechanism is configured to enter a state in which differential motion is restricted in response to the first operating mechanism accepting an operation to the first state, and to enter a state in which differential motion is not restricted in response to the first operating mechanism accepting an operation to the second state.

9. The left and right running gear, A side clutch as the operated device is provided for turning on and off the power transmission to the left and right traveling devices, 2. The walk-behind work machine according to claim 1, wherein the side clutch is configured to turn on power transmission in response to the first operating mechanism accepting an operation to the first state, and to turn off power transmission in response to the first operating mechanism accepting an operation to the second state.

10. One of the first operating mechanisms; A working clutch as the operated device that turns on and off the power transmission to the PTO shaft or the working device; a main clutch that turns on and off the power transmission from the engine to the working clutch; The left and right running gear, A differential mechanism as the operated device is provided, the differential mechanism being capable of regulating the differential between the left and right traveling devices; The working clutch is configured to turn on power transmission in response to the first operation mechanism accepting an operation to the first state, and to turn off power transmission in response to the first operation mechanism accepting an operation to the second state, 7. The walk-behind working machine according to any one of claims 1 to 6, wherein the differential mechanism is configured to enter a state in which differential motion is restricted in response to the first operating mechanism accepting an operation to the first state, and to enter a state in which differential motion is not restricted in response to the first operating mechanism accepting an operation to the second state.

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