JP2014118084A - Work vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work vehicle capable of improving workability.SOLUTION: The work vehicle comprises: a mid PTO shaft 22; a rotation sensor 37 for detecting whether the front work machine is connected to the mid PTO shaft 22 or not; and a controller 40 for maintaining operation of an engine 5 and transmission state of a mid PTO clutch 24 when determined that the front work machine is connected to the mid PTO shaft 22 on the basis of the detection result of the rotation sensor 37 in a state where the engine 5 is operated and the mid PTO clutch 24 of the mid PTO shaft 22 is in the transmission state and the retreat signal of an airframe 2 is received.

Description

  The present invention relates to a work vehicle in which a work machine can be mounted on a machine body.

  Conventionally, the technique of the work vehicle which can mount | wear a work machine with an airframe is well-known (for example, patent document 1).

  In a conventional work vehicle, when the engine is operated, the mid PTO clutch is in the transmission state, and the override switch is OFF, the engine is stopped when operated by the machine operation tool so that the machine moves backward. At the same time, the mid PTO clutch was disengaged. This is for ensuring safety by preventing the machine body from moving backward while the mid work machine (for example, a mower work machine) is driven when the override switch is OFF.

However, when a mid work machine is not connected to the mid PTO shaft, a front work machine (for example, a snowplow) is connected, and the front work machine is driven, the aircraft moves backward. There is no need to consider the safety described above.
In such a case, the user forgets to operate the override switch to ON, and operates the fuselage operating tool to the reverse side, whereby the engine is stopped and the mid PTO clutch is disengaged. Then, in order to resume the work (with the front work machine driven, the machine moves backward), the engine 5 is started, the override switch is turned on, and the mid PTO clutch is set to the transmission state. It was time consuming and the workability deteriorated.

JP 2010-172197 A

  The present invention provides a work vehicle capable of improving workability.

The work vehicle according to claim 1 is:
A PTO shaft that can alternatively connect a front work machine and a mid work machine;
Detecting means for detecting whether or not the front work machine is connected to the PTO shaft;
The front work machine is connected to the PTO shaft based on the detection result of the detection means when the engine is operated and the reverse signal of the airframe is received while the clutch of the PTO shaft is in the transmission state. A control device for continuing the operation of the engine and the transmission state of the clutch,
It comprises.

In the work vehicle according to claim 2,
The front work machine can be connected to the PTO shaft via a shaft,
The detection means is a rotation sensor for detecting rotation of the shaft connected to the PTO shaft,
When the control device receives information from the rotation sensor that the number of rotations of the shaft is a value within a predetermined range for a predetermined period, the front working machine is connected to the PTO shaft. In other cases, it is determined that the front work machine is not connected to the PTO shaft.

In the work vehicle according to claim 3,
It has an override operation tool,
When the engine is operated and the clutch is in the transmission state, the control device receives the reverse signal of the airframe, and the front work is applied to the PTO shaft based on the detection result of the detection means. When it is determined that the machine is not connected, when the override operation tool is ON, the engine operation and the transmission state of the clutch are continued, and when the override operation tool is OFF, the clutch Is turned off.

  As effects of the present invention, the following effects can be obtained.

  In claim 1, when the mid work machine is not connected to the PTO shaft and the front work machine is connected, the user forgets to operate the override switch to ON, When the engine is operated, the engine can be prevented from stopping and the transmission state of the PTO clutch can be maintained. Thereby, workability | operativity can be improved.

  In the second aspect, the control device can accurately determine whether or not the front work machine is connected to the PTO shaft.

  In claim 3, when the override operating tool is operated to be turned on, the machine body can be moved backward while the mid work machine is driven.

It is a left view of the agricultural tractor with which the mid work machine was equipped. It is a left view of the agricultural tractor with which the front work machine was equipped. It is a block diagram which shows the structure of the control mechanism of a tractor. It is a figure which shows three positions of the mid PTO switch which also serves as an override switch, (a) is a position where the amount of protrusion is the minimum, (b) is a position where the amount of protrusion is between the minimum and maximum, (c) is a position The position where the protrusion amount is maximum is shown. It is a flowchart which shows a control flow.

  Next, an agricultural tractor 1 that is an embodiment of a work vehicle according to the present invention will be described with reference to the accompanying drawings.

  As shown in FIG. 1, the tractor 1 is a work vehicle capable of transmitting power to a work machine connected to the machine body via a PTO shaft. A front wheel 3 and a rear wheel 4 are respectively arranged before and after the body 2 of the tractor 1. An engine 5 that is a power source of the tractor 1 is mounted on the front of the airframe 2, and the engine 5 is covered with a bonnet 6. The engine 5 is provided with engine start / stop means 7 for starting / stopping the engine 5 (see FIG. 3). Specifically, the engine starting / stopping means 7 is constituted by, for example, a solenoid that is an actuator for opening and closing a fuel supply valve provided in a fuel supply path to the engine 5. The engine start / stop means 7 is electrically connected to the control device 40.

  As shown in FIG. 1, a control unit 8 is provided at the rear of the airframe 2. The steering unit 8 is provided with a steering handle 9, and a seating seat 10 on which a user (operator) is seated is provided behind the steering handle 9. In the vicinity of the steering handle 9, a power switch 11, a mid PTO switch 12, a rear PTO switch 13, a boss PTO switch 26, an override switch 14 and the like are provided (see FIG. 3). In addition, a body operating tool 15 (see FIG. 1) is provided below the steering handle 9.

  A clutch housing is disposed behind the engine 5, and a transmission case 17 is disposed behind the clutch housing. The power of the engine 5 is transmitted to the rear wheel 4 through the main clutch housed in the clutch housing and the transmission housed in the transmission case 17, and at the same time, the four-wheel drive / front-wheel acceleration drive switching is performed. It is configured to be transmitted to the front wheel 3 through a mechanism.

  A rear PTO shaft 21 is provided on the rear surface of the mission case 17 so as to protrude rearward. A mid PTO shaft 22 that protrudes forward is disposed at the bottom of the mission case 17. The rear PTO shaft 21 is for transmitting power from the engine 5 to a work machine (not shown) connected to the rear of the machine body 2, such as a crushing work machine or a rotary work machine. The mid PTO shaft 22 is attached to a front work machine attached to the front portion of the machine body 2 such as a mid work machine attached to the lower center of the machine body 2 such as a mower machine 23 for mowing the lawn or a snowplow 29. (See FIG. 2) for transmitting power from the engine 5. The power of the engine 5 is transmitted to the rear PTO shaft 21 and the mid PTO shaft 22 via a main shaft or the like housed in the clutch housing.

  As shown in FIG. 1 or 2, a mid work machine (for example, a mower work machine 23) can be mounted between the front wheel 3 and the rear wheel 4, and a front work machine is provided at the front of the machine body 2. (For example, a snow remover 29) can be mounted.

As shown in FIG. 1, a gear box 27 is disposed on the upper portion of the mower working machine 23. The mower working machine 23 is connected to the mid PTO shaft 22 via the transmission shaft 28, and the mower working machine 23 is connected to the mid PTO shaft 22 by coupling the transmission shaft 28 to the gear box 27.
As shown in FIG. 2, a gear box 30 is disposed at the rear part of the snowplow 29. The snowplow 29 is connected to the mid PTO shaft 22 via a shaft (hexagon shaft) 36, and the shaft 36 is connected to the gear box 30, whereby the snowplow 29 is connected to the mid PTO shaft 22.
The front work machine (snow remover 29) and the mid work machine (more work machine 23) can be alternatively connected to the mid PTO shaft 22 (gear box 27).

  As shown in FIG. 2, a rotation sensor 37 is provided at the lower part of the machine body 2. The rotation sensor 37 is a sensor for detecting whether or not the front work machine (snowblower 29) is connected to the mid PTO shaft 22. The rotation sensor 37 is disposed so as to be present in the vicinity of the shaft 36 when the snowplow 29 is connected to the mid PTO shaft 22 via the shaft 36. The rotation sensor 37 detects the rotation of the shaft 36 by detecting a rotation pulse of the shaft 36.

  A mid PTO clutch 24 is disposed in the middle of the power transmission path from the main drive shaft to the mid PTO shaft 22, that is, between the engine 5 and the mid PTO shaft 22 (see FIG. 3). The mid PTO clutch 24 is constituted by, for example, an electromagnetic clutch, and the transmission or interruption of power to the mid PTO shaft 22 is switched by the PTO solenoid 25. That is, by energizing the PTO solenoid 25, the mid PTO clutch 24 is in the transmission state ("contact"), and by deenergizing the PTO solenoid 25, the mid PTO clutch 24 is in the disengagement state ("disconnection"). It becomes. The PTO solenoid 25 is electrically connected to the control device 40.

  Similarly, a rear PTO clutch (not shown) is disposed in the middle of the power transmission path from the main drive shaft to the rear PTO shaft 21, that is, between the engine 5 and the rear PTO shaft 21.

  The “PTO clutch” is not limited to the electromagnetic clutch as in the present embodiment, and may be, for example, a multi-plate clutch or a hydraulic clutch. In addition, the “actuator” is not limited to the solenoid as in the present embodiment, and may be another electric actuator or the like.

  The power switch 11 is a power switch for the tractor, and is composed of, for example, a key switch. The power switch 11 is electrically connected to the control device 40.

  The mid PTO switch 12 is an operating tool for artificially selecting the state of the mid PTO clutch 24 as either a transmission state or a cutoff state. The mid PTO switch 12 is electrically connected to the control device 40. The ON state of the mid PTO switch 12 corresponds to the transmission state (“contact”) of the mid PTO clutch 24, and the OFF state corresponds to the disengagement state (“disconnection”) of the mid PTO clutch 24.

As shown in FIG. 4, the mid PTO switch 12 and the override switch 14 of the present embodiment can be turned ON / OFF with a single operation tool 12a. The override switch 14 is turned on by the user when it is desired to drive the mid PTO shaft 22 even when the airframe 2 is moving backward.
Specifically, as shown in FIG. 4, the operation tool 12a of the mid PTO switch 12 and the override switch 14 of the present embodiment can switch the protruding amount in three stages (x <y < z). That is, it is possible to switch to three positions. When the projection amount is set to the minimum (x) position (see FIG. 4A), the mid PTO switch 12 is turned off and the override switch 14 is turned off. When the projection amount is at the maximum (z) position (see FIG. 4C), the mid PTO switch 12 is turned on and the override switch 14 is turned on. When the projection amount is set to a position between the minimum and maximum (y) (see FIG. 4B), the mid PTO switch 12 is turned on and the override switch 14 is turned off. However, the “override switch” according to the present invention may be configured separately from the mid PTO switch 12 and separately provided, and may be configured to operate separately.

  As shown in FIG. 3, the override lamp 18 is a lamp that is lit while the override switch 14 is ON. The override lamp 18 is electrically connected to the control device 40.

  The rear PTO switch 13 is an operation tool for artificially selecting the state of the rear PTO clutch as either a transmission state or a cutoff state. The rear PTO switch 13 is electrically connected to the control device 40. The ON state of the rear PTO switch 13 corresponds to the transmission state (“contact”) of the rear PTO clutch, and the OFF state corresponds to the disconnection state (“disconnection”) of the rear PTO clutch.

  The boss PTO switch 26 is an operation tool for artificially selecting the state of the mid PTO clutch 24 and the rear PTO clutch to either the transmission state or the cutoff state. The boss PTO switch 26 is electrically connected to the control device 40. The ON state of the boss PTO switch 26 corresponds to the transmission state (“contact”) of the mid PTO clutch 24 and the rear PTO clutch, and the OFF state is the disconnection state (“disconnection”) of the mid PTO clutch 24 and the rear PTO clutch. It corresponds.

  A machine control tool 15 shown in FIG. 1 is an operation tool that is manually operated by a user when the machine 2 is driven. The body operation tool 15 of this embodiment is configured by a pedal. In the tractor 1, the airframe 2 can be moved forward and backward by the airframe operation tool 15, and the airframe 2 is moved forward by operating the airframe operation tool 15 to the forward side, and then operated by moving backward. 2 reverses and the airframe 2 stops by being operated to a neutral position. However, the “machine operating tool” is not limited to a configuration such as a pedal, and may be configured by a lever or the like, for example. A potentiometer 38 that detects the rotation angle of the machine operation tool 15 is connected to the machine operation tool 15 (see FIG. 3).

  As shown in FIG. 3, the control device 40 described above is mounted on the tractor 1. The control device 40 controls the engine start / stop means 7 and controls the PTO solenoid 25 as an actuator. The control device 40 is electrically connected to the engine start / stop means 7, the PTO solenoid 25, the override lamp 18, the power switch 11, the mid PTO switch 12, the override switch 14, the rear PTO switch 13, the rotation sensor 37, and the potentiometer 38. Connected.

Based on the detection result of the rotation sensor 37, the control device 40 determines whether or not the front work machine (snowblower 29) is connected to the mid PTO shaft 22. Specifically, when the control device 40 receives information from the rotation sensor 37 that the rotation speed of the shaft 36 is a value within a predetermined range for a predetermined period, the control device 40 receives the front work machine from the mid PTO shaft 22. In other cases, it is determined that the front work machine is not connected to the mid PTO shaft 22. The predetermined range and the predetermined period are appropriately determined in consideration of the minimum rotation speed and the maximum rotation speed of the mid PTO shaft 22.
As described above, in the tractor 1, the control device 40 tightens the requirement for determining whether or not the front work machine is connected to the mid PTO shaft 22, so that the control device 40 can control the mid PTO shaft 22. It is possible to accurately determine whether or not the front work machine is connected.

  Based on the detection result of the potentiometer 38, the control device 40 determines whether the body operating tool 15 is operated in the forward side, the reverse side, or the neutral position. It should be noted that a known back switch is provided in the body operating tool 15, and the control device 40 determines whether or not the body operating tool 15 is operated backward based on the detection result of the back switch. It may be configured.

  Below, the control flow 100 performed by the control apparatus 40 is demonstrated with reference to FIG. As shown in FIG. 5, the control flow 100 includes steps S <b> 101 to S <b> 108.

  When the power switch 11 is turned on and the engine 5 is started, the control device 40 starts the control flow 100 (START).

  The control device 40 determines whether or not the body operating tool 15 is operated backward (step S101).

  When it is determined that the body operating tool 15 has been operated backward (when a signal for moving the body 2 backward (reverse signal for the body 2) is received) (step S101, Yes), It is determined whether or not the PTO switch 12 is ON (step S102).

  When the mid PTO switch 12 is OFF (step S102, No), the control device 40 controls the engine start / stop means 7 so as to keep the engine 5 in the operating state, and the mid PTO clutch 24 is in the disconnected state. In this manner, the PTO solenoid 25 is controlled (step S105). That is, when the backward operation of the body operating tool 15 is detected (when the backward signal of the body 2 is received), in principle, the mid PTO clutch 24 is “disengaged” without stopping the engine 5. As a result, the mid PTO shaft 22 is prevented from being driven during reverse travel.

  When the mid PTO switch 12 is ON (step S102, Yes), the control device 40 determines whether or not the front work machine (snowblower 29) is connected to the mid PTO shaft 22 (step S103). Specifically, the control device 40 determines whether information indicating that the rotation speed of the shaft 36 is a value within a predetermined range has been received from the rotation sensor 37 for a predetermined period.

When it is determined that the front work machine is connected to the mid PTO shaft 22 (step S103, Yes), the control device 40 controls the engine start / stop means 7 so as to keep the engine 5 in an operating state. The PTO solenoid 25 is controlled so that the mid PTO clutch 24 is in the transmission state (step S106). In this case, the control device 40 holds the engine 5 in the operating state and holds the mid PTO clutch 24 in the transmission state regardless of whether the override switch 14 is ON or OFF. That is, it is determined that the user wants to drive the mid PTO shaft 22 when the aircraft 2 is moving backward, and the operating state of the engine 5 is maintained so that the mid PTO shaft 22 is exceptionally driven even when the vehicle is moving backward. However, the mid PTO clutch 24 is set to “contact”.
Thereby, in the tractor 1, when the mower work machine 23 is not connected to the mid PTO shaft 22 and the snow removal machine 29 is connected, the user forgets to operate the override switch 14 to ON, When the body operating tool 15 is operated to the reverse side, the engine 5 can be prevented from stopping and the transmission state of the mid PTO clutch 24 can be maintained. Thereby, workability | operativity can be improved.

  When it is determined that the front work machine is not connected to the mid PTO shaft 22 (No at Step S103), the control device 40 determines whether or not the override switch 14 is ON (Step S104).

  When the override switch 14 is ON (step S104, Yes), the control device 40 controls the engine start / stop means 7 so as to keep the engine 5 in an operating state, and the mid PTO clutch 24 is in a transmission state. In this manner, the PTO solenoid 25 is controlled (step S107). That is, it is determined that the user wants to drive the mid PTO shaft 22 when the aircraft 2 is moving backward, and the operating state of the engine 5 is maintained so that the mid PTO shaft 22 is exceptionally driven even when the vehicle is moving backward. At the same time, the mid PTO clutch 24 is set to “contact” and the override lamp 18 is turned on.

  When the override switch 14 is OFF (No at Step S104), the control device 40 controls the engine start / stop means 7 so as to stop the engine 5, and the PTO so that the mid PTO clutch 24 is in a disconnected state. The solenoid 25 is controlled (step S108). In this case, the control device 40 controls the engine start / stop means 7 so as to keep the engine 5 in an operating state, and also controls the PTO solenoid 25 so that the mid PTO clutch 24 is in a disconnected state. Good.

  Note that the control device 40 is configured so that the body 2 is moved by the body operating tool 15 when the engine 5 is operated and the boss PTO switch 26 is ON (the mid PTO clutch 24 and the rear PTO clutch are in a transmission state). When it is determined that the front work machine is connected to the mid PTO shaft 22 based on the detection result of the rotation sensor 37 when operated so as to move backward, the engine 5 is operated, and the mid PTO clutch 24 and the The transmission state of the rear PTO clutch may be continued.

  In addition, the control device 40 is configured so that the body 2 is moved by the body operating tool 15 when the engine 5 is operated and the boss PTO switch 26 is ON (the mid PTO clutch 24 and the rear PTO clutch are in a transmission state). When it is determined that the front work machine is not connected to the mid PTO shaft 22 based on the detection result of the rotation sensor 37 when the operation is performed in reverse, when the override switch 14 is ON, the engine 5 And the transmission state of the mid PTO clutch 24 and the rear PTO clutch may be continued, and when the override switch 14 is OFF, the mid PTO clutch 24 and the rear PTO clutch may be put into a disconnected state.

  In this embodiment, the “work vehicle” is the agricultural tractor 1, but the present invention is not limited to this, and the work machine is mounted on the machine body such as a tractor for construction work. It is good also as a possible work vehicle.

As described above, the tractor 1 is
A mid PTO shaft 22 that can alternatively connect a front work machine and a mid work machine;
A rotation sensor 37 for detecting whether or not the front work machine is connected to the mid PTO shaft 22;
When the engine 5 is in operation and the mid-PTO clutch 24 of the mid-PTO shaft 22 is in a transmission state, when the reverse signal of the airframe 2 is received (the airframe 2 has been operated by the airframe operation tool 15 to move backward) In the case), when it is determined that the front work machine is connected to the mid PTO shaft 22 based on the detection result of the rotation sensor 37, the control device continues the operation of the engine 5 and the transmission state of the mid PTO clutch 24. 40,
It comprises.

  According to this, when the mid work machine is not connected to the mid PTO shaft 22 and the front work machine is connected, the user forgets to operate the override switch 14 to turn on the body operating tool. When the engine 15 is operated backward, the engine 5 can be prevented from stopping, and the transmission state of the mid PTO clutch 24 can be maintained. Thereby, workability | operativity can be improved.

In the tractor 1,
The front work machine can be connected to the mid PTO shaft 22 via a shaft 36;
The rotation sensor 37 detects the rotation of the shaft 36 connected to the mid PTO shaft 22,
When the control device 40 receives information from the rotation sensor 37 that the rotation speed of the shaft 36 is a value within a predetermined range for a predetermined period, the front work machine is connected to the mid PTO shaft 22. In other cases, it is determined that the front work machine is not connected to the mid PTO shaft 22.

  According to this, the control device 40 can accurately determine whether or not the front working machine is connected to the mid PTO shaft 22.

In the tractor 1,
An override switch 14;
When the engine 5 is operated and the mid PTO clutch 24 is in the transmission state, the control device 40 receives a reverse signal of the airframe 2 (operated so that the airframe 2 moves backward by the airframe operation tool 15). When the override switch 14 is ON when it is determined that the front work machine is not connected to the mid PTO shaft 22 based on the detection result of the rotation sensor 37, the operation of the engine 5 and the mid PTO When the transmission state of the clutch 24 is continued and the override switch 14 is OFF, the mid PTO clutch 24 is brought into a disconnected state.

  According to this, when the override switch 14 is operated to ON, the machine body 2 can be moved backward while the mid work machine is driven.

DESCRIPTION OF SYMBOLS 1 Tractor 2 Body 5 Engine 12 Mid PTO switch 14 Override switch 15 Machine body operation tool 22 Mid PTO shaft 23 More work machine 24 Mid PTO clutch 29 Snow removal machine 36 Shaft 37 Rotation sensor 40 Control device

Claims (3)

A PTO shaft that can alternatively connect a front work machine and a mid work machine;
Detecting means for detecting whether or not the front work machine is connected to the PTO shaft;
The front work machine is connected to the PTO shaft based on the detection result of the detection means when the engine is operated and the reverse signal of the airframe is received while the clutch of the PTO shaft is in the transmission state. A control device for continuing the operation of the engine and the transmission state of the clutch,
Characterized by comprising:
Work vehicle. The front work machine can be connected to the PTO shaft via a shaft,
The detection means is a rotation sensor for detecting rotation of the shaft connected to the PTO shaft,
When the control device receives information from the rotation sensor that the number of rotations of the shaft is a value within a predetermined range for a predetermined period, the front working machine is connected to the PTO shaft. In other cases, it is determined that the front work machine is not connected to the PTO shaft.
The work vehicle according to claim 1. It has an override operation tool,
When the engine is operated and the clutch is in the transmission state, the control device receives the reverse signal of the airframe, and the front work is applied to the PTO shaft based on the detection result of the detection means. When it is determined that the machine is not connected, when the override operation tool is ON, the engine operation and the transmission state of the clutch are continued, and when the override operation tool is OFF, the clutch Characterized in that it is shut off,
The work vehicle according to claim 1 or claim 2.

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