JPS5832984Y2 - Wheel rotation control device for agricultural machinery - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a wheel rotation control device for an agricultural machine such as a tiller.

This rotation control device is equipped with a hydraulic pump with a plunger and a hydraulic motor, and by changing the oil flow rate and oil flow direction of the oil supplied from the hydraulic pump to the hydraulic motor, it is possible to continuously control the rotational speed of the wheel. It is capable of changing and selecting the direction of rotation, and is used in place of or in conjunction with a gear transmission mechanism in agricultural machinery.

When an agricultural machine equipped with such a rotation control device is suddenly stopped or started, excessive hydraulic pressure is temporarily applied to the components of the rotation control device, resulting in a disadvantage that the durability of the components is impaired.

Therefore, the present invention aims to provide a rotation control device which ensures the durability of its component parts by attaching a mechanism to prevent sudden stops and sudden starts. The details will be explained based on the following.

Figure 1 is a side view of the power tiller, with □ tension case M
Wheels 1' on both sides are mounted on an axle 1 extending to both sides of the lower part of the transmission case M.An engine E is connected to the front part of the transmission case M via a clutch case 2, and a main shaft 3 driven by the engine E drives the transmission case M. PT in medial anteroposterior direction
A rotary tiller R is installed in the hitch part 5 at the rear of the mission case M so as to drive the O-axis 4, and the PTO shaft 4 is
The handle 6 is configured to extend toward the rear of the machine so as to drive the rotary tiller R.

2 and 3 are a side sectional view and a plan sectional view of the hydraulic transmission device A, respectively, in which the lower surface T of the case a is connected to the mission case M.
A pump body 9 is connected to the front part of the case a, and a motor body 10 is connected to the side part of the case a.The input shaft 11 inserted into the pump body 9 has a large number of plungers. 12, and a movable swash plate 14 that adjusts the oil flow rate and controls the oil flow direction for the hydraulic pump is connected to a vertical drive pin 15 and a support pin 15.
A hydraulic motor 1 is supported on
A fixed swash plate 18 is installed opposite the hydraulic motor 17, and the hydraulic pump 13 and the hydraulic motor 1T are connected to each other via the oil passage 19, 19' of the pump body 9 and the oil passage 20° 20' of the motor body 100. and the charge pump P connects the oil path 1.
It is constructed so that pressure oil can be applied to the 9 and 19' sides.

Further, a drive shaft 21 at the front of the mission case M driven by the main shaft 3 and the input shaft 11 are connected to an Oldham joint 22, and a gear 23 of the output shaft 16 is connected to the drive shaft 21 at the front of the mission case M. to drive the axle 1.

The movable swash plate 14 is used to adjust the oil flow rate and control the oil flow direction.
As shown in FIG. 4, the swash plate operation mechanism B for rotating the drive pin 15. An arm 24 whose one end is fixed to the upper end of the drive pin 15. A cam plate 28 is pivotally supported above the case a by a support shaft 25, has an arc-shaped cam hole 26, and has a roller 21 attached to the other end of the arm 24 fitted into the cam hole 26, and a rear side of the case a. The gear group G
It also includes a channel-shaped shifter 30 that engages in a lever 29' groove protruding from one end of a drive arm 29 of a shifter 39 that operates the transmission gear, and a rod 31 that connects the shifter 30 and the cam plate 28.

An operating rod 32 for changing the speed of the tiller is provided near the handle 6, and the operating rod and the swash plate operating mechanism B are connected at both ends to the operating rod 32 and the shifter 30. It is interlocked with the speed change rod 33.

The surface shift rod 33 is supported by being fitted into a rod holder 34 fixed to an appropriate portion of the handle frame 6'.

The portion of the transmission rod 33 supported by the rod holder 34 and the structure of the rod holder 34 are shown in FIG.

That is, the speed change rod 33 has an annular flange 33a formed on its outer surface in which an appropriate number of restricting holes 33b are bored.
The inner diameter of the cylinder W34a into which the speed change rod 33 in the flat rod holder 34 is to be fitted is approximately the same size as the outer diameter of the flange 33a, and the bottom wall 34b of the cylindrical portion 34a and the speed change rod 33 are inserted into the cylinder W34a. The lid body 34c to be fitted to the portion 34a is attached to the cylindrical portion 34 with an O-ring interposed therebetween.
A sealed space 35 is formed between the transmission rod 33 and the shift rod 33, and the sealed space 35 has an oil filling hole 31 and an oil 38 that are formed in the cylindrical portion 34a and can be sealed by a stopper 36.
Enclose it.

In other words, the oil damper with the speed change rod 33 as a piston and the rod holder 34 as a cylinder acts as the speed change rod 33.
It is formed in the middle of.

The length of the cylindrical portion 34a is determined by the relative axial direction of the speed change rod 33 with respect to the rod holder 34 when the operating rod 32 is inserted into the maximum position of the forward high-speed groove and when it is inserted into the maximum position of the reverse groove. Determined by the difference in position.

That is, for example, when the operating rod 32 is at the maximum position of the forward high speed groove at 1, the flange 33a is at the position A as shown in the figure, and when the operating rod 32 is at the neutral position and at the maximum position of the backward groove, the flange 33a is at the maximum position of 1. When inserted, the collar portion 33a is located at the opening and opening positions.

When using an agricultural machine such as a tiller that is equipped with the rotation control device of the present invention configured as described above (hereinafter referred to as the device of the present invention), when attempting to stop the agricultural machine that is moving forward at high speed. In this case, the operator performs an operation to disengage the operating rod 32 from the forward high-speed groove and return the operating rod 32 to the neutral position.

At this time, the speed change rod 3 connected to the operating rod 32
3 moves in the direction of the arrow, but since the sealed spaces 35', 35// located on both sides of the flange 33a are communicated by the throttle hole 33b, the oil 38 moves only gradually through the throttle hole 33b. This is not done and the oil damper effect is produced.

Therefore, even if the operator attempts to quickly return the operating rod 32 to the neutral position, the operation will be hindered by the oil damper effect, and the rotation of the movable swash plate 14 in response to the movement of the flange 33a toward the bottom will be prevented. The decrease in the oil flow rate supplied from the hydraulic pump 13 to the hydraulic motor 1γ, which can only be carried out gradually, is carried out gradually.

As a result, unlike conventional products, excessive hydraulic pressure is not applied to the component parts of the present device, so there is no risk of the durability of the component parts being impaired.

This effect is the same when starting suddenly, i.e., when moving the collar 33a from the mouth to the mouth, or when suddenly stopping the agricultural machine in the backward state, i.e., when moving the collar 33a from the mouth to the mouth. Needless to say, it will be demonstrated.

Moreover, as a result of preventing sudden starts, the operational safety of agricultural machinery equipped with the device of the present invention is improved.

Incidentally, since agricultural machinery is naturally equipped with a brake device, there will be no inconvenience in actual use even if the proposed device does not cause a sudden stop.

Furthermore, since the rod holder 34 that forms the cylinder of the oil damper also functions as a support member for the speed change rod 33, the agricultural machine on which the present device is mounted does not need to be particularly large or have a special structure.

In the above embodiment, the hydraulic pump 13 is provided with a movable swash plate 14, and the hydraulic motor 17 is provided with a fixed swash plate 18, but in contrast to this, a fixed swash plate is provided on the hydraulic pump.
For hydraulic power transmission devices in which a movable swash plate is installed opposite to the hydraulic motor, or a movable swash plate is installed opposite to both the hydraulic pump and the hydraulic motor, the swash plate operating mechanism and speed change described above are attached to the drive pins of each movable swash plate. Of course, the present invention can be carried out by connecting the transmission irons and supporting the transmission irons on the rod holder as described above.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Figure 1 is a side view of a power cultivator equipped with the device of the present invention, and Figures 2 and 3 are a side sectional view and a plan view, respectively, of a hydraulic power transmission device according to the present invention. 4 is a perspective view of the swash plate operating mechanism, and FIG. 5 is a side sectional view of the rod holder. 13... Hydraulic pump, 14... Movable swash plate, 17... Hydraulic motor, 32... Operating rod, 33... Speed change rod , 34...
Rod holder, A...Hydraulic transmission device, B...
... Swash plate operation mechanism.

Claims (1)

[Scope of utility model registration request] A hydraulic pump and a hydraulic motor are provided as a set of plungers, and the hydraulic pump and hydraulic motor are used to adjust the oil flow rate and control the oil flow direction in a wheel rotation control device for an agricultural machine that transmits engine driving force to the wheels. /or A swash plate operation mechanism for rotating a movable swash plate installed opposite to a hydraulic motor, and a speed change rond that connects an operating rod mounted on the steering wheel, the speed change rond being a piston, and the speed change rond being a piston. 1. A wheel rotation control device comprising an oil damper whose cylinder is a rod holder fitted around a speed change rod to support a speed change rod.