JP3534593B2 - Chain tension adjustment device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field of a chain tension adjusting device provided in a binder raising device or the like.

[0002]

2. Description of the Related Art Generally, this type of chain tension adjusting device is
The chain suspended between the drive wheel and the idler wheel is tensioned based on the forward / backward movement of the idler wheel, but in the conventional one, the idler holder supported so as to move forward and backward is compressed by a compression spring in the forward direction. Since it is configured to be urged, when a large load is applied to the chain, the idler wheel retreats significantly against the urging force of the compression spring, which causes the chain to loosen.

[0003]

Therefore, it has been proposed to provide a stopper for restricting the retracting range of the idle wheel holder. However, the idle wheel holder moves forward in accordance with the extension deformation of the chain, and therefore the idle wheel holder. In order to control the backward movement of the chain, it was necessary to frequently adjust the stopper position according to the extension of the chain.

[0004]

The present invention has been made in view of the above circumstances in order to solve these problems, and it is suspended between a drive wheel and an idler wheel. A chain tension adjusting device for tensioning a chain based on forward / backward movement of an idler wheel, wherein the chain tensioning adjuster guides an idler wheel holder supporting the idler wheel back and forth, and the idler wheel retracts. Of the guide cylinder, a guide cylinder holder that supports the guide cylinder so as to move forward and backward, and a stopper, a stopper that restricts the backward movement of the guide cylinder, and the guide cylinder is biased in a predetermined rotation direction. A torsion spring is provided, and an inclined guide surface for guiding the guide cylinder rotating in a predetermined direction to move in the forward direction is formed at the stopper contact portion of the guide cylinder. In other words, since the idle wheel holder that supports the idle wheel is pressed in the forward direction by the guide tube that is biased in the rotating direction, if the inclined guide surface of the guide tube is set to an appropriate angle, the guide tube has a reverse rotation prevention function. (Equivalent to the reverse rotation prevention principle of the worm gear) can be provided. Therefore, it is possible to regulate the retreat of the idle wheel holder due to a large load without frequently adjusting the stopper position according to the extension of the chain, and as a result, the chain tension adjustment can be substantially automated. Further, the position of the stopper is configured to be adjustable in the advancing / retreating direction of the guide cylinder. In other words, the initial contact position between the inclined guide surface and the stopper can be easily adjusted, and if the inclined guide surface has a short guide stroke, the stopper position is adjusted according to the chain extension (the adjustment frequency is Less than before)
can do.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Next, one of the embodiments of the present invention will be described with reference to the drawings. In the drawings, 1 is a binder for cutting and bundling stalks, and the binder 1 is a pair of left and right traveling wheels 2 at an intermediate position in the longitudinal direction of the machine body.
In front of the traveling wheel 2, a cutting unit 3 for cutting and binding the stems is provided, while behind the traveling wheel 2, an operating handle 4, an engine 5, and a transmission case 6 are provided. There is.

The cutting unit 3 divides the stems by a divider 7, a raising device 8 for raising the stems, a cutting blade device 9 for cutting the roots of the stems, and a binding device for binding the cuttings ( (Not shown) and the like. Further, the raising device 8 provided with the chain tension adjusting device 10 of the present invention has the drive wheel 12 and the idler wheel 13 installed at the upper and lower positions of the raiser case 11, and is provided between the drive wheel 12 and the idler wheel 13. , A raising chain 15 in which a plurality of raising claws 14 are rotatably pivotally attached.
On the ascending side of the raising chain 15, the raising claws 14 are erected to raise stalks, while on the descending side, the raising claws 14 are laid down and raised to be housed in the case 11. All of these basic configurations are conventional.

Reference numeral 16 is an idler wheel holder that rotatably holds the idler wheel 13, and the idler wheel holder 16 has a substantially U-shape in side view so as to support the idler wheel support shaft 17 at its lower end portion. The guide tube 18 is formed on the upper end of the guide tube 18 to be described later.
An advancing / retreating guide shaft 16a that is fitted in the inner peripheral portion of the
A detent shaft 16b, which is fitted into a detent hole 19a of a guide cylinder holder 19 to be described later and is capable of advancing and retracting to detent the idler wheel holder 16, is integrally provided.

The guide cylinder 18 does not allow the idle wheel holder 16 to move back and forth, and the lower end surface of the guide cylinder 18 restricts the backward movement of the idle wheel holder 16, but the guide cylinder 18 itself raises the case. A guide hole 19b of the guide tube holder 19 fixed to 11 is fitted and supported in a guide hole 19b so as to be movable back and forth and rotatable, and its retreat is restricted based on contact with a stopper 20 described later.

Reference numeral 21 denotes a torsion coil spring provided on the outer peripheral portion of the guide cylinder 18. One end of the torsion coil spring 21 is locked to the guide cylinder holder 19, while the other end is fixed to the guide cylinder 18. Guide cylinder 1 because it is locked
8 is biased in a predetermined rotation direction.

A guide cylinder 18 that contacts the stopper 20.
A spiral inclined guide surface 18a that guides the guide cylinder 18 that rotates in the urging direction of the torsion coil spring 21 in the forward direction is formed at the upper end of the. That is, the guide cylinder 18 biased by the torsion coil spring 21 presses the idler wheel holder 16 in the forward direction by the guide of the inclined guide surface 18a, so that the pull-up chain 15 can be maintained in an appropriate tension state. Moreover, the inclination angle (advance angle) of the inclined guide surface 18a is set to be relatively small, and the guide cylinder 18 has the reverse rotation prevention function (equivalent to the reverse rotation prevention principle of the worm gear). It is possible to regulate the retreat of 16 without performing frequent stopper position adjustment according to the extension of the raising chain 15. Reference numeral 18b is a rotation restricting protrusion that contacts the stopper 20 at the upper end position of the inclined guide surface 18a and restricts further rotation of the guide cylinder 18.

On the other hand, the stopper 20 is attached to the guide cylinder holder 19 in the vertical direction, but the stopper 20 of this embodiment is screwed into a nut 22 fixed to the guide cylinder holder 19. Therefore, the stopper position can be adjusted forward and backward based on the turning operation of the stopper 20. As a result, the inclined guide surface 18a
It is possible to easily adjust the initial contact position between the stopper 20 and the stopper 20. In addition, in the case where the guide stroke of the inclined guide surface 18a is short, the stopper position adjustment according to the extension of the raising chain 15 (the adjustment frequency is conventionally Less than
The pulling chain 15 can be maintained in an appropriate tension state based on the above.

In the structure constructed as described above, the raising chain 1 suspended between the drive wheel 12 and the idle wheel 13.
5, the tension of the idler wheel 13 is adjusted based on the forward / backward movement of the idler wheel 13.
In addition, the guide cylinder 1 that restricts the backward movement of the idle wheel holder 16 is applied.
8, a guide tube holder 19 that supports the guide tube 18 so as to move forward and backward and turn, a stopper 20 that restricts the guide tube 18 from retracting, and a twist that urges the guide tube 18 in a predetermined rotation direction. A coil spring 21 is provided, and an inclined guide surface 18 for guiding the guide cylinder 18 rotating in a predetermined direction to move forward in a stopper contact portion of the guide cylinder 18.
Since a is formed, the guide cylinder 18 biased by the torsion coil spring 21 presses the idler wheel holder 16 in the forward direction by the guide of the inclined guide surface 18a, and maintains the pulling chain 15 in an appropriate tension state. Become. Since the inclination angle (advance angle) of the inclined guide surface 18a is set to be relatively small, the guide cylinder 18 has a reverse rotation prevention function (equivalent to the reverse rotation prevention principle of the worm gear), and is free from a large load. The backward movement of the wheel holder 16 will be restricted. Therefore, it is not necessary to frequently adjust the stopper position according to the extension of the raising chain 15, and as a result, the tension adjustment of the raising chain 15 can be substantially automated.

Moreover, the stopper 20 is the guide cylinder 1.
Since the position can be adjusted in the advancing / retreating direction of 8, the initial contact position between the inclined guide surface 18a and the stopper 20 can be easily adjusted. Moreover, in the case where the guide stroke of the inclined guide surface 18a is short, the pulling-up chain 15 is properly tensioned based on the stopper position adjustment according to the extension of the pulling-up chain 15 (the adjustment frequency is less than in the conventional case). There is an advantage that can be maintained.

Needless to say, the present invention is not limited to the above-mentioned embodiment, and the chain tension adjusting device of the present invention can be implemented by other than the raising device.

[Brief description of drawings]

FIG. 1 is a side view of a binder.

FIG. 2 is a front view of a raising device.

FIG. 3 is a side view of the same.

FIG. 4 is a schematic front view of a chain tension adjusting device.

FIG. 5 is a schematic side view (including movement of a guide cylinder) of the above.

[Explanation of symbols]

1 binder 8 Raising device 10 Chain tension adjustment device 12 drive wheels 13 idler wheel 15 Raising chain 16 Idling wheel holder 18 Guide tube 18a inclined guide surface 19 Guide tube holder 20 stopper 21 torsion coil spring

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography Sho 48-82382 (JP, U) Steady Sho 62-21819 (JP, U) Steady Sho 57-7920 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) A01D 57/22

Claims (2)

(57) [Claims] 1. A chain tension adjusting device for tension-adjusting a chain suspended between a drive wheel and an idler wheel based on forward and backward movements of the idler wheel, wherein the idler wheel is attached to the chain tension adjuster. A guide tube that guides the supporting idle wheel holder to move back and forth, and that restricts the backward movement of the idle wheel holder, and a guide tube holder that supports the guide tube so that it can move forward and backward and turn are connected to the backward movement of the guide tube. A stopper for restricting the contact and a torsion spring for urging the guide cylinder in a predetermined rotation direction are provided, and further, a guide cylinder rotating in a predetermined direction is guided to move forward in a stopper contact portion of the guide cylinder. A chain tension adjusting device having an inclined guide surface. 2. A chain tension adjusting device, wherein the stopper according to claim 1 is configured to be positionally adjustable in a forward and backward direction of a guide cylinder.