JPH0534422Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention aims to facilitate operation by controlling the speed of a hydrostatic continuously variable transmission using a speed change operation actuator according to the amount of operation of a human operating tool. This article relates to a speed change operation structure for a certain working machine.

[Conventional technology]

As a speed change operation structure for this type of work machine, there is a structure previously filed by the present applicant (Utility Application No. 157594/1983), which consists of the rotation of a pedal as a human operating tool. A rotation sensor is provided at the support shaft portion to detect the amount of operation set for this pedal, and based on the amount detected by this sensor, the operating member of the hydrostatic continuously variable transmission is controlled to change speed by a transmission motor capable of forward and reverse rotation.

[Problem that the invention attempts to solve]

In a mechanism that relies on such electronic equipment, once a failure occurs, it becomes impossible to perform gear shifting operations at all, so a countermeasure for this problem has been desired.

The purpose of the present invention is to provide a hydrostatic continuously variable transmission that can perform gear shifting operations even in situations where gear shifting operations cannot be performed electrically due to such failures. .

[Means for solving problems]

The characteristic configuration of the present invention is based on the fact that the operating member of the hydrostatic endless transmission and the actuator for shifting operation are connected by a first mechanical linkage mechanism that can be released from the linkage, and that the operating setting amount is detected by an artificial operating tool. A control device is provided to drive and control the actuator, the artificial operating tool and the operating member are configured to be connectable and disconnectable by a second mechanical linkage mechanism, and the second mechanical linkage mechanism The first mechanical linkage mechanism is configured so that the first mechanical linkage mechanism can be released from the linkage in a state where the artificial operating tool and the operating member are connected, and the effects thereof are as follows.

[Effect]

In other words, if there is no failure in the control device, etc.,
The actuator is actuated by an amount corresponding to the amount set to the human operating tool, and the speed change of the hydrostatic continuously variable transmission is controlled by this speed change operation actuator. At this time, a configuration is adopted in which the second mechanical linkage mechanism is removed to prevent disturbance to the operating member caused by an artificial operating tool. In addition, if a failure occurs in the control device or actuator, a second mechanical linkage mechanism is installed between the human operation and the operation member instead of removing the first mechanical linkage mechanism, The operating member can be operated manually and mechanically by operating the operating tool.

[Effect of idea]

Therefore, although an operation mode is normally adopted in which the operating burden on the driver is reduced by power shifting the hydrostatic continuously variable transmission device using an actuator, in the event of a failure of the control device or the like, the manual operating tool and the aforementioned operating member are used. Shifting operations can be performed by simply mechanically linking the two.

〔Example〕

The gear shift operation system will be explained with reference to an agricultural tractor as an example of a working machine. As shown in Figure 3,
The engine 1 is installed in the front of the aircraft, and the hydrostatic continuously variable transmission 3 (hereinafter referred to as
The agricultural tractor is constructed by disposing a transmission case 5 (referred to as HST) and disposing a speed change pedal as a human operating tool 4 for the HST 3 at the right front of the driver's seat 2.

Next, the gear shift operation system will be explained. As shown in FIGS. 1 and 2, an operating arm as an operating member 7 is rotatably attached to one end of an operating shaft 6 that drives and controls the swash plate of the HST 3, and a first mechanical linkage mechanism 8 to be described later. A drive arm 1 of an electric motor as an actuator 9 for speed change operation via
It is linked to 0. This first mechanical linkage mechanism 8
In this case, a relay balance arm 11 is disposed at the linkage intermediate portion, one end of this balance arm 11 and the operating arm 7 are connected by a first link 12, and the other end of the balance arm 11 and the drive arm 10 are connected to each other by a first link 12. are connected by a second link 13. On the other hand, a potentiometer-type first rotation sensor 14 is attached to the swing shaft of the speed change pedal 4 to detect the swing angle as the operation setting amount of the speed change pedal 4, and this sensor 14 detects the swing angle by a computer. is output to the built-in control device 15. The signal processed by this control device 15 is output to the electric motor 9,
The HST 3 is set to a speed change state corresponding to the operation setting amount of the speed change pedal 4. By swinging the speed change pedal 4 back and forth, the HST 3 can change the speed forward and back. Further, a second rotation sensor 16 of a potentiometer type is attached to the swing axis of the balance arm 11 to detect the swing amount of the balance arm 11,
It is configured to detect the actual swing amount of the operating arm 7 of the HST 3 and output a feedback signal to the control device 15.

On the other hand, one end of an auxiliary link 17 is pivotally supported at a connecting fulcrum between the first link 12 and the balance arm 11.
When the electric motor 9 is used to change the speed of the HST 3, the auxiliary link 17 is overlapped with the first link 12 and fixed at its other end with a pin 18, so that it is integrated with the first link 12. .
If a failure occurs in the control device 15 or the like in this state, the pin 18 can be removed and the other end of the auxiliary link 17 can be connected to the swing arm 19 on the side of the gear change pedal 4. The connecting pin in this case also serves as the pin 18. In the above, the auxiliary link 17 and the first link 12 are referred to as the second mechanical interlocking mechanism 20.

[Another Embodiment] As shown in FIG. 4, the first link 12 and the operating arm 7 may be disconnected from each other, and the auxiliary link 17 may be directly attached to the operating arm 7. The second mechanical linkage mechanism 20 in this case is only the auxiliary link 17.

The first and second mechanical linkage mechanisms 8 and 20 may be a combination of wires, gears, and the like.

As the actuator 9, a motor other than an electric motor, a cylinder, etc. may be used.

The artificial operating tool may be an operating lever, button, etc. that is operated by hand rather than the foot.

The embodiments described above may be used in other working machines such as combines.

Note that although reference numerals are written in the claims section of the utility model registration for convenience of comparison with the drawings, the present invention is not limited to the structure of the attached drawings by such entry.

[Brief explanation of the drawing]

The drawings show an embodiment of the speed change operation structure for a work machine according to the present invention, and FIG. 1 is a side view showing a first mechanical linkage mechanism and a second mechanical linkage mechanism, and FIG. 2 corresponds to FIG. 1. A plan view, FIG. 3 is a side view of the agricultural tractor, and FIG. 4 is a side view showing another embodiment of the first mechanical linkage mechanism and the second mechanical linkage mechanism. 3... Hydrostatic continuously variable transmission, 4... Human operating tool, 7... Operating member, 8... First mechanical linkage mechanism, 9... Actuator for speed change operation, 15...
Control device, 20... second mechanical linkage mechanism.

Claims (1)

[Scope of utility model registration request] The operation member 7 of the hydrostatic continuously variable transmission 3 and the actuator 9 for speed change operation are connected to each other by a first
A control device 15 is provided which is connected by a mechanical linkage mechanism 8 and drives and controls the actuator 9 based on detection of an operation setting amount by the artificial operating tool 4, and the artificial operating tool 4 and the operating member 7 are connected and controlled. It includes a releasable second mechanical linkage mechanism 20, and
A work machine configured such that the first mechanical linkage mechanism 8 can be released from the first mechanical linkage mechanism 8 in a state where the artificial operating tool 4 and the operating member 7 are connected by the second mechanical linkage mechanism 20. Shift operation structure.