JP2000023542A - Stretcher for elongation of endless belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a tension of an endless belt be held at about constant even the endless belt is elongated by a change with passage of the time, etc., and make deformation, breaking, etc., of the endless belt be inhibited even generating an unusual load in the endless belt, in the endless belt in which a tight roller of the endless belt is enforced by a spring. SOLUTION: This tensioner has a controller 16 engaging a cam pipe 14 pressing a tight roller 4 to a tensioning direction from outside of a supporting shaft 11 of the tight roller 4 and a controller 16 attaching on a cam face 15 provided on the cam pipe 14 and controlling a regression of the cam pipe 14 and extruding the cam pipe 14 by revolution of the cam pipe 14. On the other hand, a controlling mechanism 18 revolving and enforcing the cam pipe 14 with a twist spring 17 and transferring the tight roller 4 to the tensioning direction by a revolution of the cam pipe 14 when the endless belt 5 is constructed, then the controller 16 regresses to an unusual load against the spring 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tensioning device for elongating an endless belt provided in a combine or the like.

[0002]

2. Description of the Related Art In general, many endless belts are used for mobile agricultural machines such as combine harvesters. For example, as a pre-processing unit of a combine, there is known a pre-processing unit in which a divider device a composed of an endless band is attached in front of a raising device as shown in FIG. In such a divider device a, the support shaft c of the tight roller b is urged in the tensioning direction by the compression spring d to hold the endless belt in a tensioned state.

However, when the endless belt urged in the tension direction is elongated due to a change with time, the tight roller b moves downward, and the set size S of the compression spring d becomes large. The urging force of d decreases and sufficient tension does not act on the endless belt. At the same time, the compression allowance H of the compression spring d also increases,
When an abnormal load occurs in the endless belt, the tight roller b
Move too much and move too close to the sprocket supporting the other end of the endless band, causing the endless band to loosen.

As a result, the endless belt is disengaged from the sprocket or the tight roller b, or the raised claw cannot be raised or lowered normally, so that the raised case or the raised claw often wears and is deformed into an endless band. In some cases, breakage occurred.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned situation, and an object of the present invention is to make an endless band such as a pull-up chain grow due to a change over time. In some cases, the tensioning device for elongation of the endless band can maintain the tension of the endless band substantially constant, and can prevent deformation, breakage, etc. of the endless band even if an abnormal load occurs in the endless band. It is intended to provide.

[0006]

Means for Solving the Problems In order to solve the above problems, a first technical means taken by the present invention is to provide an endless belt in which an endless tight roller is biased by a spring. The second technical means is to attach an endless band tight roller with a spring as a second technical means. In the energized endless zone, between the spring and the tight roller,
An adjusting mechanism for making the tension of the endless belt substantially constant with respect to the elongation of the endless band is provided. As a third technical means, the tight roller is tensioned to the support shaft of the tight roller of the endless band. A cam pipe that presses in the direction is removably fitted to the outer surface, and a restricting body that pushes the cam pipe in the forward direction by rotating the cam pipe by contacting a cam surface provided on the cam pipe and restricting retraction of the cam pipe is provided. When the cam pipe is turned by a torsion spring and the endless belt is extended, the cam pipe is turned to move the tight roller in the tensioning direction, and the regulating body is elastically supported by a spring. The restricting member is configured to retreat against the spring against an abnormal load in the endless band.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in FIGS. 1 and 2, reference numeral 1 denotes a pre-processing unit of a combine, and 2 denotes a divider mounted in front of a raising device of the pre-processing unit 1.
In FIG. 1, a raising chain 5 as an endless belt is wound around a driving sprocket 3 and a tight roller 4, and a plurality of raising claws 6 are mounted on the raising chain 5 so as to be able to rise and fall.

A raising claw 6 which protrudes forward and rises with the rotation of the raising chain 5 causes the raised culm to rise. Reference numeral 7 denotes a raising case, and reference numeral 8 denotes a driving shaft of the driving sprocket 3.

As shown in FIGS. 3 and 4, the tight roller 4 includes a bracket 9 for supporting the tight roller 4, a plate 10 fixed to the upper end thereof, and a support shaft 11 in the vertical direction.
Are integrally formed and are slidable in the direction of arrow a. Further, a guide body 12 of the support shaft 11, a guide plate 13 of the raise claw 6, and the like are fixed to the raise case 7.

Numeral 14 denotes a vertically movable cam pipe fitted to the support shaft 11 and having a spiral cam surface 15 formed at an upper end thereof and having a predetermined inclination angle abutted on a regulating body 16. As a result, the tight roller 4 is raised and pressed in the tension direction of the chain 5.

That is, the restricting body 16 restricts the cam pipe 14 from retreating upward due to contact with the cam surface 15,
Further, when the cam pipe 14 rotates, the cam surface 15 having the inclination angle slides along the regulating body 16, and accordingly, the cam pipe 14 is pushed downward in the forward direction to press the tight roller 4 in the tensioning direction.

A torsion spring 17 is wound around the cam pipe 14.
When the tension is weakened by extending the pull-up chain 5 by urging the cam pipe 14 in the direction of arrow B in FIG. 3, an adjusting mechanism 18 that rotates the cam pipe 14 to move the tight roller 4 in the tensioning direction. Is configured. 19 is a locking pin for the torsion spring 17.

The regulating body 16 is integrally and vertically suspended from the lower surface of the support plate 20. Pins 21 and 22 are erected on the upper surface of the support plate 20.
The springs 23 are inserted and supported by 22. The upper ends of the pins 21 and 22 are vertically slidably supported by a plate 24 fixed to the case 7 so that the restricting body 16 is elastically supported by the springs 23 and 23. When an abnormal load is applied to 5, the regulating body 16 is retracted against the bias of the springs 23,23. 25 is a split pin for retaining the pins 21 and 22, and 26 is a flat washer. It should be noted that the flat washer 26 and the plate 20 may be set so as to have some play.

Pipes 27, 27 are inserted through the springs 23, 23 as stoppers for regulating the amount of compression. The pipe 27 is formed to have a dimension shorter than the set dimension L of the spring 23 by a certain shrinkage allowance K.

Since the present invention is configured as described above, when the pulling chain 5 as an endless band is extended due to a change with time, the tight roller 4 is brought into a play state and raised, and the tension of the chain 5 is reduced. At this time, the cam pipe 14 constituting the adjusting mechanism 18 is
5, the tight roller 4 is pushed out by the regulating body 16, and as shown in FIG. 5, the tight roller 4 is moved in the direction of arrow C to raise and hold the chain 5 in a tensioned state. Then, since the revolving cam pipe 14 is restricted from retreating by the restricting body 16, the work can be smoothly performed while keeping the tension of the raised chain 5 constant.

Even if an abnormal load is applied to the pulling chain 5, as shown in FIG. 6, the restricting body 16 restricting the retraction of the cam pipe 14 resists the urging of the springs 23, 23. Since the chain 5 is retracted, the chain 5 is not deformed or damaged. Moreover, since the spring 23 has a constant shrinkage allowance K due to the pipe 27,
The spring 23 is not greatly compressed and raised, and the chain 5 is not loosened.

[0017]

In summary, the present invention relates to an endless belt in which an endless band tight roller is urged by a spring, and the spring contracts against an abnormal load acting on the endless band between the spring and the tight roller. An adjustment mechanism is provided to keep the allowance constant, and an adjustment mechanism is provided between the spring and the tight roller to make the tension of the endless band substantially constant with respect to the extension of the endless band. A cam pipe that presses the tight roller in the tensioning direction is externally fitted to the support shaft of the roller so as to be able to move forward and backward, contacts the cam surface provided on the cam pipe to restrict the retraction of the cam pipe, and rotates the cam pipe by rotating the cam pipe. On the other hand, the cam pipe is turned by a torsion spring while the regulating body is pushed out in the forward direction, and when the endless belt is extended, the cam pipe turns to turn the tight roller. In addition to forming an adjusting mechanism for moving the restricting member in the tension direction, the restricting member is elastically supported by a spring, and the restricting member is configured to retreat against the spring against an abnormal load of the endless band. The spring that urges the endless band has a fixed shrinkage allowance even when the endless band expands over time, so even if an abnormal load is applied to the endless band, the spring is greatly compressed and the endless band is loosened. There is nothing. Then, even if the endless band is extended, the work can be performed smoothly while maintaining the tension of the endless band substantially constant.

Further, in the structure in which the cam pipe is externally fitted to the support shaft of the tight roller to constitute the adjusting mechanism, when the endless belt is extended, the cam pipe rotated by the bias of the torsion spring is pushed out by the regulating body. Since the tight roller is moved in the tension direction, it can easily cope with the extension of the endless band, but even if an abnormal load occurs in the endless band, the regulating body retreats against the spring, so the endless band Can be prevented from being deformed and damaged.

[Brief description of the drawings]

FIG. 1 is a left side view of a divider including an endless band attached to a pre-processing unit of a combine.

FIG. 2 is a longitudinal sectional view of the same.

FIG. 3 is an enlarged side view of a main part of the same.

FIG. 4 is a front view of the same.

FIG. 5 is a side view showing a state in which the tight roller has moved with the extension of the endless belt.

FIG. 6 is a side view showing a state where an abnormal load is applied to the endless band and the spring is compressed.

FIG. 7 is a side view showing a conventional example.

[Description of Signs] 4 Tight roller 5 Endless belt (pulling chain) 11 Support shaft 14 Cam pipe 15 Cam surface 16 Regulator 17 Torsion spring 18 Adjusting mechanism 23 Spring

Claims (3)

[Claims] An adjusting mechanism for maintaining a contraction allowance of a spring between the spring and the tight roller in an endless belt in which the tight roller of the endless belt is urged by a spring against an abnormal load acting on the endless belt. A tensioning device for elongation of an endless band, characterized by comprising: 2. An endless belt in which a tight roller of an endless belt is urged by a spring, and an adjusting mechanism is provided between the spring and the tight roller to make tension of the endless band substantially constant with respect to extension of the endless band. A tensioning device for elongation of an endless belt. 3. A cam pipe for pressing the tight roller in a tensioning direction is fitted on a support shaft of the endless tight roller so as to advance and retreat, and abuts on a cam surface provided on the cam pipe to regulate the retraction of the cam pipe. And, while the regulating member which pushes the cam pipe in the forward direction by the rotation of the cam pipe is provided, the cam pipe is rotated and urged by the torsion spring, and when the endless band is extended, the cam pipe is rotated to tighten the tight roller in the tension direction. Wherein the regulating body is elastically supported by a spring, and the regulating body is configured to retreat against the spring against an abnormal load of the endless band. Tension device against stretching.