JPH0716932Y2 - Stepless speed change operation structure of traveling vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a continuously variable transmission operating structure for a traveling vehicle in which a working device is vertically movable, and more specifically, a split structure configured to adjust a belt winding radius. The present invention relates to an operation structure of a continuously variable transmission mechanism including a pulley for a traveling vehicle.

[Prior Art] Conventionally, as a belt type continuously variable transmission mechanism, the split pulley is urged by a spring in a direction in which the belt winding radius increases, and the tension of the split pulley is changed by operating a tension pulley for shifting. There is a structure for adjusting the winding radius of the belt with respect to the gear. Also, as a gear shifting operation structure, the gear shifting operation tool and the tension pulley are interlocked via a mechanical linkage mechanism such as a rod. There are some (not listed).

[Problems to be solved by the invention]

However, in order to configure the continuously variable transmission mechanism for traveling speed change and mechanically configure the operation system, the biasing force of the spring provided in the split pulley must be increased from the viewpoint of preventing slippage in the split pulley. However, the operation load of the continuously variable transmission mechanism becomes large due to the force due to the biasing force of the spring, which makes it difficult to handle.

Therefore, it is conceivable to set the link ratio of the operation system to a large value to reduce the operation load on the operator, but even with this configuration, there is a limit to the reduction of the operation load, and the operation stroke is It becomes large and unwieldy, and there is room for improvement.

Furthermore, as an example of a riding type rice transplanter equipped with a seedling planting device as a traveling vehicle in which working devices are vertically movable, or an agricultural tractor equipped with a cultivator, an example of this type of vehicle is a ridge in a field. When it reaches, the work device is normally raised to rotate the machine body and simultaneously perform deceleration operation.

However, performing the raising operation of the working device and the turning and decelerating of the machine body at substantially the same time is troublesome and there is room for improvement.

An object of the present invention is to rationalize a speed change operation structure that can reduce an operation load as much as possible without increasing an operation stroke of an operation tool that operates a split pulley, and that can easily reduce a traveling speed when a working device is raised. The point is to configure.

[Means for solving problems]

A feature of the present invention is that a working device is movably connected to a traveling machine body via a link mechanism that is operated to move up and down by an actuator, and a direction in which a belt winding radius increases on an output shaft of an engine mounted on the traveling machine body. A split pulley that is biased by a spring is provided on the drive transmission, and a pulley for fixing the belt winding radius is provided on the input shaft of the traveling transmission case. A belt that is wound around these and a tension pulley for shifting are provided, respectively, and a continuously variable transmission mechanism is provided. And a flexible portion that allows the tension pulley to operate in a direction in which the belt winding radius of the split pulley is reduced with respect to an operation system that mechanically links the gear shifting operation tool and the gear shifting tension pulley. And a balance spring for reducing the operation load caused by the biasing force of the spring to the operation system on the side of the operation tool from the interchange part, and further, the raising operation of the link mechanism. In addition, an operated portion for operating the tension pulley in the direction of reducing the belt winding radius of the split pulley in response to the operating force of the link mechanism is formed in the operation system on the tension pulley side from the interchange portion. The action and effect are as follows.

[Action]

According to the above feature, the urging force of the spring provided on the split pulley acts in the direction of increasing the belt winding radius, and the balance spring acts in the direction of decreasing the belt winding radius by the tension arm. The operating load acting on the operating tool can be reduced by balancing the urging forces. Further, when the working device is raised, the tension pulley is operated in the direction of reducing the belt winding radius by the power transmitted from the link mechanism to the operated portion, so that the traveling speed is reduced and this operation is allowed in the interchangeable portion. It is not transmitted to the system of the operation tool for shifting.

In other words, in the present invention, the gear shift operation force is reduced by the balance spring when the gear is manually changed, and the powerful power from the link mechanism is generated without any special operation when the work device is raised. The continuously variable transmission mechanism is automatically operated in the decelerating direction by utilizing it, and at the time of this deceleration, there is no influence such as changing the gear shift position of the gear shifting operation tool, and there is no influence of the biasing force of the balance spring. .

[Effect of device]

Therefore, the operation load is reduced without increasing the operation stroke of the gear shifting operation tool of the continuously variable transmission mechanism having the spring-biased split pulley, and the gear shifting operation is artificially performed when the working device is raised. Even if it is not performed, the traveling speed is automatically decelerated, so that the gear change operation structure that does not bother the operator can be reasonably constructed.

〔Example〕

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

As shown in FIG. 4, power from the engine (1) is transmitted to a traveling transmission case (2) through a belt type continuously variable transmission mechanism (A), and output from the transmission case (2). A transmission system is formed to drive the front and rear wheels (3) and (4) to form a traveling machine body (B), and a boarding operation section (C) is formed at the center of the traveling machine body (B). In addition, an example of a traveling vehicle in which a seedling planting device (D) as a working device is connected to a rear end of the traveling machine body (B) via a link mechanism (6) that is vertically moved by a hydraulic cylinder (5) Configure the rice transplanter as a passenger.

As shown in FIG. 4, the boarding operation unit (C) includes a steering handle (7) for operating the front wheels (3),
A main transmission lever (8) linked to the transmission case (2),
Also, a seat (9) is provided, and a shift lever (10) is provided as an example of an operating tool for operating the continuously variable transmission mechanism (A) on a side portion of the seat (9).

As shown in FIGS. 1 and 2, the continuously variable transmission mechanism (A)
Is a split pulley (11) provided on the output shaft (1a) of the engine (1), a pulley (12) having a fixed belt winding radius provided on the input shaft (2a) of the transmission case (2), It consists of a rotating belt (13) and a tension pulley (14) for speed change. The split pulley (11) is provided with a spring (15) for urging in the direction of increasing the belt winding radius. (14) is supported by the swing end of a swing-type tension arm (16).

As shown in FIG. 1, the gearshift lever (10) has its base end connected and fixed to a swing bracket (18) which is swingably supported by a horizontal axis (P) with respect to a body frame (17). At the same time, it is extended to the side of the seat (9) through the guide member (19) so that the swing operation can be performed around the axis (P).
Moreover, the operation position can be fixed by the guide member (19).

Further, the operated subject which is located at one end of the swing bracket (18) and below the swing bracket (18) and which is swingably supported by the horizontal axis (Q) with respect to the machine body frame (17). A connecting rod (21) is provided so as to extend over the elongated hole (20h) as the interchangeable portion of the contact bracket (20) as a member, and the contact bracket (20) and the tension arm (16) are the operation rod. By being connected via (22), operating the speed change lever (10) in the direction (H) shown in FIG. 1 will increase the traveling speed of the aircraft, and operating it in the direction (L) will increase the traveling speed of the aircraft. Is being reduced.

In addition, a balance spring (2) is provided between the swing bracket (18) and the machine body frame (17) in a direction to reduce the operation load caused by the urging force of the spring (15) provided on the split pulley (11).
3) is activated.

As shown in FIGS. 1 and 3, a push button (24) is provided at the tip of the speed change lever (10), and an engagement pin (25) and a push button (24) provided on the speed change lever (10) are provided. ) And the engaging groove (19) formed in the engaging member (25) and the guide member (19) by the push operation of the push button (24).
a)… Disengaged with the push button (24)
Is set to a free state, and the engaging pin (25) and the engaging groove (19a) are urged by the urging force of the spring (26) provided on the speed change lever (10).
... is engaged.

Then, when the seedling planting device (D) is lifted while the traveling speed is set by the speed change lever (10),
As shown by the phantom line in FIG. 1, the tip of the link mechanism (6) abuts the abutment bracket (20) to automatically decelerate the continuously variable transmission (A), and at the same time, the long hole ( 20h)
Does not affect the gear shift position of the gear shift lever (10) without transmitting this deceleration operation to the system of the gear shift lever (10), and is not affected by the balance spring (23).

In the speed change operation structure, in order to make the operation load caused by the urging force of the spring (15) provided on the split pulley (11) as uniform as possible, the tension arm (16) can be operated in the direction of stretching the belt (13). The higher the tension, the larger the ratio of the tension arm (16) to the operation rod (22), and the more the tension arm (16) is operated in the direction to stretch the belt (13), the balance spring (23). )
In order to set a large arm ratio of the swing bracket (18) with respect to, the respective operation phases are determined and arranged.

That is, the magnitude of the moment of the balance spring (23) acting on the swing bracket (18) provided at the base end of the speed change lever (10) is as shown in FIG.
The action point of the balance spring (23) with respect to, that is, the arm lengths (G _L ) ... (G _H ) with respect to the dead point (DP) are larger in the deceleration direction, and therefore are larger in the deceleration direction in the embodiment.

Further, the operation load (F _A ) of the continuously variable transmission mechanism (A) that acts on the shift lever (10) due to the spring (15) and the shift load (10) due to the balance spring (23). The return load (F ₂₃ ) can be represented in a graph as shown in FIG. 5, and as shown in the same figure, the operation load (F _A ) and the return load (F A) of the continuously variable transmission (A) are further shown. ₂₃ ) and the combined operation load (F ₁₀ ) of the speed change lever (10) becomes a low average value in the operation range as shown in the graph. The value is low throughout the operating range of 10).

[Another embodiment]

The present invention may be implemented by being applied to, for example, a carrier vehicle as a traveling vehicle other than the above-described embodiment.

[Brief description of drawings]

The drawings show an embodiment of a continuously variable transmission operation structure for a traveling vehicle according to the present invention. FIG. 1 is a side view showing the operation structure, FIG. 2 is a partially cutaway plan view of the continuously variable transmission mechanism, and FIG. FIG. 4 is a vertical cross-sectional view showing the gear shift lever locking structure, FIG. 4 is an overall side view of the riding rice transplanter, and FIG. 5 is a graph showing the operating load of the gear shift lever. (1) …… Engine, (1a) …… Engine output shaft,
(2) …… Traveling transmission case, (2a) …… Running transmission case input shaft, (6) …… Link mechanism, (10) …… Operating tool, (11) …… Split pulley, (12) …… Pulley, (13)…
… Belt, (14)… Tension pulley, (15)… Spring for urging split pulley, (20)… Operated part, (20H)…
... accommodation section, (23) ... balance spring, (A) ... continuously variable transmission mechanism, (B) ... traveling machine body, (D) ... working device.

Claims (1)

[Scope of utility model registration request] 1. A working device (D) is movably connected to a traveling machine body (B) via a link mechanism (6) which is operated to move up and down by an actuator, and an engine ( The split pulley (1) biased by the spring (15) in the direction in which the belt winding radius increases on the output shaft (1a) of (1).
1) is provided, a pulley (12) having a fixed belt winding radius is provided on the input shaft (2a) of the transmission case (2) for traveling, and a belt (13) wound around these and a tension pulley (14) for speed change are provided.
The continuously variable transmission mechanism (A) is provided with each of them, and the tension pulley (14) is provided to the operation system that mechanically links the speed change operation tool (10) and the speed change tension pulley (14). ) Forms a flexible part (20H) that allows the split pulley (11) to move in a direction that reduces the belt winding radius, and with respect to the operating system on the side of the operating tool (10) from the flexible part (20H). A balance spring (23) for reducing an operating load caused by the urging force of the spring (15), and further receiving the operating force of the link mechanism (6) when the link mechanism (6) is raised. Operated part (2) that operates the tension pulley (14) in the direction to reduce the belt winding radius of the split pulley (11).
0) is formed in the operation system on the side closer to the tension pulley (14) than the interchange portion (20H) is a continuously variable transmission operation structure for a traveling vehicle.