JPS5915855Y2 - Swing device of walking rice transplanter - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a swing device for a walk-behind rice transplanter, and more specifically, to a swing device that has an appropriate cushion when traveling both in the field and on the road.

A walk-behind rice transplanter has wheels on the left and right sides, and a float is attached to the rice transplanter body so that it receives buoyancy from the rice field and bears part of the weight of the rice transplanter body as it moves around the field. The planting machine placed at the lower end is always kept at a constant height relative to the rice field surface during work, and even if the wheels of the rice transplanter move vertically due to unevenness of the tiller, the seedlings are planted at a constant depth. It is designed to be.

Therefore, it is necessary that the left and right wheels of the walking rice transplanter move up and down relative to the rice transplanter body, and that the left and right wheels also move up and down independently.

Therefore, walk-behind rice transplanters are equipped with a device that forces the left and right wheels to partially conform to the unevenness of the tiller, but this device usually consists of a single hydraulic cylinder. It has a swing device to ensure that both wheels are firmly in contact with the ground even when the left and right wheels are placed on plowing platforms of different shapes (heights).

This swing device is designed to ensure that the left and right wheels of the rice transplanter are securely in contact with the tiller and do not lose driving force by expanding and contracting a single cylinder unit.

Its structure is such that a hydraulic cylinder unit is arranged in the length direction of the rice transplanter, and the center part of a balance lever arranged in the width direction of the rice transplanter is pivotally supported at the tip of the piston rod. One end of the connecting rod is connected to the top, and the other end is connected to a swing arm that also serves as a chain transmission case and swings the wheels up and down, and the left and right wheels are on plowing platforms of different heights and depths. However, the balance lever rotates within an appropriate range around the pivot point at the end of the piston rod, allowing the left and right wheels to be grounded.

However, walk-behind rice transplanters not only travel within the field, but also need to travel on public roads and farm roads when traveling from one work site to the next, or from a storage location to the field. The left and right wheels are placed under the same conditions as if they were located at the deepest point of the tiller.

That is, in order to maximize the ground clearance of the rice transplanter, the rice transplanter is operated with the wheels lowered to the lowest limit.

By the way, when driving on the road, the wheels support the entire weight of the rice transplanter's body, so if there is no elasticity mechanism between the wheels and the body, the machine will directly pick up unevenness on the road surface, which will cause poor drivability. becomes.

Therefore, the balance lever is pivoted to be freely movable by a predetermined amount in the axial direction of the piston rod, and is biased in the downward direction of the wheel by a compression spring wound around the piston rod.

By doing this, the aircraft is not only supported and road drivability is improved, but also the balance lever is given the habit of returning to an equilibrium state, so that the aircraft can maintain a horizontal attitude.

However, unless the compression spring is very strong, it is difficult to maintain the horizontal posture of the machine when traveling on the road, and the same is true if the compression spring does not evenly press the center of the balance lever.

However, if the compression spring is made strong, the swing response of the wheel when driving in the field becomes inertia, so generally,
This is achieved by using a somewhat weak compression spring, and instead providing a stopper mechanism that restricts the rotation of the balance lever within a predetermined range.

Therefore, the present invention aims to simplify the structure and obtain the above-mentioned functions without providing a separate stopper mechanism, and by eliminating as much machining on the piston rod side as possible in order to achieve the pivot connection between the piston rod and the lever take-up. It is something to do.

For this purpose, the present invention forms the balance lever with a U-shaped side cross section so that the pressing force of the compression spring is evenly received on the back surface of the lever, and the piston rod is inserted through this back surface. This feature is characterized in that the insertion hole has a stopper function, and elongated holes along the axial direction of the piston rod are provided on the upper and lower surfaces of the balance lever so that it can be connected to the piston rod with a pin.

Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings.

First, in Fig. 1, reference numeral 1 indicates the main body of the walking-type rice transplanter, and the swing arm 4, which also serves as a transmission case with a built-in chain etc., can swing vertically, with the transmission shaft 3 to which the output of the engine 2 is transmitted as the pivot point. A wheel 5 is attached to its free end via a drive shaft 6, and is arranged symmetrically on both the left and right sides.

Therefore, for example, the wheel 5 is configured to swing up and down due to the circular motion of the swing arm 4 about the transmission shaft 3 in response to unevenness of the tiller.

Furthermore, a float 7 is attached to the lower part of the rice transplanter main body 1 by a movable member such as a link, so that the float 7 can bear part of the weight of the rice transplanter main body 1 by the buoyant force it receives within the rice field surface. and this float 7
One end of a plowing depth sensor rod 8 is attached to the plowing depth sensor rod 8, which detects the depth of the plowing platform and operates a hydraulic system switching valve of a swing device, which will be described later.

A seedling stand 9 is attached to the rear end of the rice transplanter main body 1, and the seedlings m are planted while being cut out by a planting machine placed at the lower end thereof.

A swing device 10 is configured at the center position in the width direction of the rice transplanter main body 1, and a hydraulic cylinder unit 11 that serves as a drive source for the swing is arranged, and an oil path switch of a hydraulic system that expands and contracts this hydraulic cylinder unit 11. Pressure oil can be supplied to the cylinder unit 11 via the valve 12.

The upper end of the sensor rod 8 is connected to this oil passage switching valve 12 via a bell crank 12a, a connecting rod 12b, and the float 7 moves up and down with respect to the rice transplanter main body 1 (more precisely, the float floats on a circular surface). Therefore, when the wheel moves up and down and the wheel 5 goes down, the oil path is switched by ``relatively floating the float 7'', and when the plow is deep, the hydraulic cylinder unit 11 piston rod 1
1a is extended according to the depth, and the wheels 5 are lowered.

Piston rod 11 of this hydraulic cylinder unit 11
a has a flange 11 b, and this flange 11 b
The compression spring 13 whose one end is received by the piston rod 1
The compression spring 13 is strong enough not to be completely bent even when the piston rod 11a is fully extended, and the tip of the piston rod 11a has a A pin 11C is implanted, and the center portion of the balance lever 14, which extends in a direction perpendicular to the piston rod 11a, is pivoted by the pin 11C. 14a, so that the balance lever 14 can move along the axial direction of the piston rod 11a.

This balance lever 14 is formed by bending a plate material by press working or the like, and has a U-shaped side cross section with a pair of horizontal plates 14b and vertical plates 14C, which are open on the side opposite to the cylinder. There are cutout windows 1 at both ends of the vertical plate 14C forming a
4d, and the end of a connecting rod, which will be described later, is inserted into the balance lever 14 through this cutout window 14d.

The vertical plate 14C forming the back surface of the balance lever 14 is flat, and the tip of the piston rod 11aQ is inserted between the horizontal plates through an insertion hole 14e provided in the flat surface. The end of the compression spring 13 wound around the piston rod 11a is connected to the vertical plate portion 14 around the insertion hole 14e.
C is used as a spring seat and is tightly pressed against this.

Here, the insertion hole 14e is made slightly larger in diameter than the tip end of the piston rod 11a to allow the balance lever 14 to rotate through a predetermined angle.

Further, at both ends of the balance lever 14, there are connecting rods 15 for forcibly rotating the swing arm 4 about the transmission shaft 3.
One end of the connecting rod 15 is connected by a connecting pin 15a, and the other end of the connecting rod 15 is connected to a drive arm 16 protruding from the swing arm 4 by a connecting pin 15b.

Next, the operation of the swing device according to the present invention will be explained.

First, the left and right wheels 5 are placed on a plowing board with the same level of unevenness, or
When traveling on a flat tiller, the piston rod 11 of the hydraulic cylinder unit 11 changes depending on the depth of the tiller.
a expands and contracts, and the wheels 5 are brought into contact with the tiller.

In addition, when the left and right wheels 5 move on plowing platforms at different depths, it is necessary to lower only the deeper wheel by a greater amount, and in this case, the piston rod 11a is extended. The shallower wheel touches the ground first, but since the deeper wheel has not reached the tiller, the piston rod will extend until it touches the tiller.

In this case, since the shallower wheel 5 has touched the ground first, the extension of the piston rod 11a does not lower it any further, but only the deeper wheel is lowered, and the lever 14
The piston rod 11a is not perpendicular to the piston rod 11a around the pin 11C, and the insertion hole 14
Rotate until it is regulated by C.

Even at this time, the compression spring 13 is in contact with and presses against the spring seat on one side of the balance lever 14, and has the effect of restoring the balance lever 14 to the posture perpendicular to the piston rod 11a.

Therefore, if the left and right wheels move to the same height, the balance lever 14 immediately returns to the state perpendicular to the piston rod 11a as shown in FIG.

Furthermore, the piston rod 11a and the balance lever 14 are
Since the pin 11C is fitted into the elongated hole 14a and is pivotally supported, unevenness of the tiller that does not hinder the planting of seedlings can be appropriately absorbed by the play between the pin 11C and the elongated hole 14a. .

When this walk-behind rice transplanter travels in the field, the floats 7 bear and support a percentage of the total weight, so the weight applied to the wheels 5 is small, and the pin 11C is at the A position and the compression spring 13 is Since the pressing force is reduced, the lever 14 can be easily rotated, allowing the wheel 5 to conform to the unevenness of the tiller.

When the rice transplanter is run on a public road or farm road in preparation for rice planting work or as a finishing touch, the floats 7 from the rice transplanter main body 1 are suspended in the air, and there is no buoyancy from the rice field, so the load applied to the wheels 5 is As a result, the overall ground clearance is lowered, and the float may hit obstacles on the road, so it is necessary to lower the wheels 5 to increase the ground clearance.

Therefore, when the piston rod 11a is fully extended,
The extension of the piston rod 11a pushes the balance lever 14 through the compression spring 13, the pin 11C moves to the B position, and the swing arm 4 is rotated by the connecting rod 15, approaching the upright state.

Then, the compression spring 13 itself becomes the most compressed state and becomes hard, the compression spring 13 becomes difficult to bend, the swing of the balance lever 14 is considerably suppressed, and the restoring force is strengthened, so that the wheel 5 does not move up and down on some unevenness. It disappears.

As explained above, according to the present invention, the balance lever is formed to have a U-shaped side cross section, and the compression spring is received on the back surface of the lever, so that the pressing force of the compression spring is applied evenly and the balance lever is moved to the equilibrium position. Since the piston rod is inserted and supported through the insertion hole formed on the back surface of the balance lever, the rotation of the balance lever can be regulated at a predetermined angle without requiring a separate stopper mechanism. Can be done.

Furthermore, the structure for connecting the piston rod and the take-up lever can be achieved by simply machining a long hole in the take-up lever and providing a pin on the piston rod side, making the structure extremely simple.

[Brief explanation of the drawing]

FIG. 1 is a side view of the walking rice transplanter according to this invention, FIG. 2 is a plan view of the swing device, and FIG. 3 is a side view of the same. DESCRIPTION OF SYMBOLS 10... Swing device, 11... Hydraulic cylinder unit, 11 a... Piston rod, 11 b... Flange, 11 C...
...Pin, 13...Compression spring, 14...
・Take-up lever, 14a... Long hole, 14b...
...Horizontal board, 14C...Vertical board, 14d...
...Notch window, 14 e...Insertion hole.

Claims (1)

[Scope of utility model registration request] The left and right wheels of a rice transplanter main body having a float that can move up and down are supported via swing arms so as to be able to swing up and down independently of each other, and the swing arms
The balance lever is attached to the main body of the rice transplanter and the center part is supported by the piston rod of a hydraulic cylinder unit that automatically expands and contracts in response to the vertical movement of the float.The lever is linked to both the left and right ends of the lever, and is wrapped around the piston rod. In a walk-behind rice transplanter in which the lever is biased in the downward direction of the wheels by a compression spring, the lever has a U-shaped side cross section with a back surface serving as a seat for the spring receiver. A piston rod insertion hole is formed on the back surface of the piston rod, and the tip of the piston rod is inserted and supported in the insertion hole, and an elongated hole is provided on the upper and lower surfaces of the piston rod along the axial direction of the piston rod, and the piston rod is inserted through the elongated hole. A swing device for a walk-behind rice transplanter, characterized in that the tip of the piston rod and the take-up lever are connected by a pin, so that the take-up lever is pivoted to be freely movable by a predetermined amount in the axial direction of the piston rod.