JPS6239632Y2 - - Google Patents

Description

[Detailed description of the invention] Conventionally, as a device for adjusting the elongation of a chain used for lifting grain culms or transporting grain culms in a combine harvester, etc., a long hole in the vertical direction is provided in the chain case. In many cases, the chain was tensioned by supporting the bearings of the side wheels and moving them to the tension side using bolts, etc., but in recent years automatic tension devices, which are easy to operate, have become preferred. It has become like that. FIG. 4 shows an example of this. In the figure, 21 is a chain that is wound around a sprocket 23 that is pivotally supported on a rotating shaft provided at the upper part of the chain case 22, and a wheel that is pivoted on the lower part. A rotary ring 25 is provided at the tip of the attached tension arm 24, and the chain 21 is tensioned from the inside by the rotary ring 25. In this case, in order to provide a rotating ring inside the chain case, it is necessary to form the chain case wide. Furthermore, since there is a risk that a finger or the like may be inserted into the elongated hole 26 through which the spindle of the rotating ring passes, a member such as a rubber plate 27 with a slit cut into the back side of the case 22 is used as shown in FIG. , there were some inconveniences such as having to make a special provision.

The present invention attempts to overcome these conventional drawbacks. Hereinafter, the present invention will be specifically explained based on the embodiments shown in FIGS. 1 to 3.

Reference numeral 1 denotes a grain culm lifting case of a combine harvester, etc., which is installed on the front side of a reaping device so as to be inclined so that its upper end is located at the rear. Reference numeral 2 denotes a transmission case screwed onto a threaded rod 4 protruding from the outside of the upper end of the lifting case 1, with a rotating shaft protruding inside the lifting case 1, on which the sprocket 5 is pivotally supported. ing. A wheel 5' is rotatably mounted on the lower end of the lifting case 1, and a chain 5' having a plurality of lugs 7' pivotally supported on the wheel 5' and the sprocket 5 is attached to the wheel 5' and the sprocket 5. 7 is wound. Reference numeral 6 denotes an annular pedestal which is rotatably fitted into the mounting part 3 between the transmission case 2 and the lifting case 1, and has an arc-shaped elongated hole 6' in the part through which the screw rod 4 passes. A member for tensioning the chain 7 is provided to protrude into the case. That is, in the drawer case 1, an arc-shaped elongated hole 8 with the rotation axis as the center is formed from a line connecting the upper and lower rotation axes to a position substantially perpendicular thereto. 8, a rod 9 installed in the pedestal 6 is passed through, and a support portion 10 is provided at the end of the support rod 9 with a semicircular arc shape at the part that contacts the chain and a notch at the other end. It is fixed with screws.

The reason why one end of the support part 10 is cut out is to make it as close to the sprocket as possible. Further, the elongated hole 6' of the pedestal is formed so that the support rod 9 of the support portion can move over the entire length of the elongated hole 8 of the raising case. 12 is the bearing part 1
0 is a spring for tensioning the chain 7 wound around the sprocket 5 and the wheel 5' from the inside, one end of which is supported at the center of the outside of the lifting case 1, and the other end supported by an annular pedestal. It is hooked to the outer end of 6.

The present invention is constructed as described above, and includes a sprocket 5 supported rotatably on a rotating shaft provided at the upper end of the lifting case 1, a roller 5' provided at the lower end, and
Since the chain 7 is wound close to the sprocket 5 and between the support part 10 that tensions the chain 7, when hanging the chain 7, the support part 10 must first be placed under the tension of the spring. When pushed down against resistance, the support rod 9 descends through the arc-shaped elongated hole 8,
When it reaches the lower end, sprocket 5, bearing 1
0 and the wheel 5' is the shortest, so it should be multiplied at this time.

When the chain is wound, the spring 12
Due to the tension, the support section constantly applies tension to the chain 7 from inside, allowing the chain 7 to rotate smoothly. That is, when power is transmitted from the power source of the aircraft to the transmission case 2 by an appropriate transmission mechanism,
The sprocket 5, which is supported by the rotating shaft, rotates, and the chain 7 rotates accordingly.
The lug 7' moves from the bottom to the top and serves to raise the grain rod.

As the chain 7 is used, its rotating parts wear out and its overall length gradually increases, but the chain does not loosen because the support part constantly tensions the chain due to the action of the spring 12.

As mentioned above, the present invention uses a member that supports the inside of the chain 7 against the elongation of the chain 7, which is stretched between wheels that are supported on a rotating shaft provided in a chain case for pulling grain culms. In an automatic tensioning device that applies tension to the chain case, a support rod 9 is inserted through a long hole 8 drilled in the chain case into a pedestal 6 provided on the back surface of the chain case so as to be rotatable on one rotation axis. A support part 10 is fixed to the support rod 9, the part of which contacts the chain 7 has a semicircular arc shape, and the other end is notched, and the support part 10 is brought close to the wheel body to constantly apply tension to the chain 7. Since the long hole 8 is covered by the pedestal 6, the support part 10 can be provided sufficiently close to the sprocket 5, which is a wheel, and there is no need to particularly increase the width of the chain case.

Further, since the back side of the long hole 8 through which the support rod 9 that supports the support part 10 passes through and rotates is always covered on the back side by the pedestal 6 that supports the support part 10, the long hole 8 is No special member or the like is required for blocking, and safety can be maintained reliably.

[Brief explanation of the drawing]

The drawings show one embodiment of the automatic tensioning device of the present invention, in which Fig. 1 is an overall internal front view, Fig. 2 is a sectional view from the upper side of the same, Fig. 3 is a rear view of main parts, Fig. 4, Fig. 5 1 is a front view and a rear view showing a conventional example. 1... Lifting case, 2... Transmission case, 3...
...Mounting part, 4...Screw rod, 5...Sprocket,
6...Pedestal, 6'...Long hole, 7...Chain, 8
... Long hole, 9 ... Support rod, 10 ... Support part.

Claims (1)

[Scope of utility model registration request] An automatic tensioner that automatically applies tension with a member that supports the inside of the chain 7 against elongation of the chain 7, which is stretched between wheels that are supported on a rotating shaft provided in a chain case for pulling grain culms. In the device,
A support rod 9 is provided on the pedestal 6 provided on the back surface of the chain case so as to be rotatable on one rotation axis, passing through a long hole 8 drilled in the chain case. A support part 10 whose contact part is shaped like a semi-circular arc and the other end is notched is fixed, and the support part 10 is brought close to the wheel body to constantly apply tension to the chain 7, and the long hole 8 is covered by the pedestal 6. Automatic tension device.