JPH039617Y2 - - Google Patents

Description

[Detailed explanation of the invention] The conventional grain conveying device using a chain provides a large tension to the chain that prevents the chain from coming off the drive sprocket even when a large torque is applied, and when an overload is applied, It was constructed in such a way that the shear pin inserted into the transmission part broke, or the interposed torque limiter was activated, cutting off power transmission.

However, the method of inserting a shear pin is troublesome to replace when it breaks, and the torque limiter is extremely expensive.

Therefore, it was proposed in 1987-74235 that the tops of the teeth of the sprocket be formed in an arc shape so that when a load equal to the torque set by the drive sprocket's shear pin, torque limiter, etc. is applied to the conveyor chain, the conveyor chain will come off the sprocket. proposed as a number.

The above proposal has almost achieved its purpose when the load increases gradually, but if a large impact load is applied, the conveying chain will not come off the sprocket, and of course an overload will be applied to the drive shaft. This also affected the conveyor chain, which had the disadvantage of causing the conveyor chain to stretch in a short period of time.

With this invention, not only when the load gradually increases and becomes overloaded, but also when an overload occurs due to impact, the conveying chain can be accurately disengaged from the sprocket, preventing damage to various parts and stretching of the conveying chain. The grain culm conveying device is intended to provide a safety device for the grain culm conveying device, and the grain culm conveying device is provided with a chain tension body with a spring for tensioning the conveying chain in the vicinity of a drive sprocket for rotating the conveying chain. ,
The present invention is characterized in that the arcuate portions of the tops of the teeth of the driving sprocket are cut off so that the conveying chain can be removed at a limit torque, and the connecting portions between the rising surfaces of the teeth and the cut surfaces are formed at corners.

The embodiment shown in the drawings will be explained below.1
is a threshing device mounted on one side of a machine base having a traveling device 2, and a frame 4 of a reaping device 5 is attached to the front of the threshing device via a mounting frame pivotally supported on a horizontal shaft 3. The device 5 is the branching body 6...
Cutting blade 7, grain culm pulling body 8..., raking wheel 9..., stock raking chains 10, 10, and stem raking chain 1
1, 11, etc., and the terminal end of the horizontal transfer chain 12 extending from the rear of the stocking chain 10 on the right side to the rear of the stocking stocking chain 10 on the left side, and the threshing device 1.
There is a stock carrier 13 between the feed chain 1a and the feed chain 1a.
is stretched, and above it is provided a panicle side transport body 14 consisting of a lateral transport section and a rear transport section. It is made up of.

Further, the drive sprocket 17 of the lateral transfer chain 12 is attached to a drive shaft 19 rising from a transmission case 18, and an arm 2 pulled by a spring 21 is attached to a cylinder 20 loosely fitted to the drive shaft 19.
2 and a support arm 24 of a tension roller 23 pressed against the lateral transfer chain 12 are fixed.

The drive sprocket 25 of the stock scraping chain 10 on the left side in the direction of travel is attached to a drive shaft 27 rising from the transmission case, and a cylinder loosely fitted to the drive shaft 27 is fitted with a spring 28 similar to the cylinder. A support arm 3 that pivotally supports a tension roller 30 that is in pressure contact with the tensioned arm 29 and the stock scraping chain 10.
1 is fixed.

Furthermore, the floating sprocket 32 that meshes with the stock head scraping chain 10 on the right side is supported by a shaft 33 erected on the machine frame, and an arm 34 protruding from a cylinder loosely fitted to the shaft 33 is attached to the tip. It supports a tension roller 35 and is tensioned by a spring 36.
A roller 3 wrapped around the rear part of the stock chain 10
7 is fixed to the same rotating shaft 39 as the roller 38 around which the right front part of the horizontal transfer chain 12 is wound, so that the stem scraping belt 11 on that side, the stock scraping chain 10 and the scraping chain in front of it are The folding wheel 9 is driven by a lateral transfer chain 12.

Furthermore, the conveyance chain 1 of the stock source conveyor 13
3a is tensioned between a drive sprocket 40 and a driven sprocket 41 as shown in FIG. The part that is freely pivoted and goes forward is a spring 46.
Since the tension rollers 44 and 45, which are pivotally supported at both ends, are urged to rotate in the counterclockwise direction, the tension rollers 44 and 45 are pressed against the stock conveyance chain 13a.

When the stock transfer chain 13a is extended or the load is small, the tension arm 43 is pulled by the spring 46 and rotates counterclockwise, and the tension rollers 44 and 45 move the stock transfer chain 13a.
a is pushed to the position shown by the dotted line and tensed, and when the load becomes large, it is pushed back against the spring 46 to the position shown by the solid line.

Even if the tension arm 43 swings in this way, the stock conveyor chain 1 relative to the drive sprocket 40
The winding angle of 3a hardly changes, and the amount of rotation of the tension arm 43 is smaller than that using one tension roller, so that the amount of expansion and contraction of the spring 46, that is, the variation in tension can be reduced. .

The teeth A of each of the drive sprockets 17, 25, 40 mentioned above are lower than the normal height shown by the dotted line with respect to the diameter of the chain roller B, as shown by the solid line in FIG. 6, and the height of the corner C is lowered. is usually the position where the chain roller B comes off the corner at the limit torque set by the shear pin or torque limiter.

In the drawing, 47 is a detachment prevention plate, 48 is a transmission case, 49 is a drive sprocket for the ear side conveyor 14, and 50 is an adjuster for spring tension.

Next, to explain the action, branch 6...
The grain culms separated are raised by the grain culm lifting body 8, then raked by the raking claws of the stem raking chain 11 and the stock raking chain 10, and then by the cutting blade. The root part is harvested, and the reaped grain culm is transported laterally by the horizontal transfer chain 12 and the front part of the ear-side conveyor 14, the stalk part is inherited by the stalk-side conveyor 13, and the stem part is transferred to the ear-side conveyor 14. 14 and supplied to the threshing device 1.

During such reaping and threshing work, the load on each operating section varies depending on conditions such as the degree of grain culm, whether it is hard or soft, whether the conveying section is clogged, etc. In particular, if the conveyance section becomes clogged, overload will occur.

At that time, if an overload is applied to the right-hand stock pull-in chain 10 and the lateral transfer chain 12, the drive sprocket 17 will come off the lateral transfer chain 12, and if an overload is applied to the left-hand stock pull-in chain 10, the drive sprocket will disengage. 25 comes off, and when an overload is applied to the stock transfer chain 13a, its drive sprocket 40 comes off.

When the overload gradually increases and reaches the limit torque, the drive sprockets 17 and 2
If the top corner of the tooth profile 5 and 40 is made into an arc shape as shown by the dotted line in Figure 6, the chain tension will be within the appropriate limit line and the chain jumping operating torque will reach the limit as shown by line A in Figure 7. Torque is reached and the chain separates from the drive sprocket.

However, if the drive sprocket with the tooth profile described above catches a hard object such as a rod into the raking wheel 9 and a shocking overload occurs, the chain jumping torque will increase as shown by the line B. does not come off the drive sprocket.

On the other hand, if the tooth profile of the drive sprocket is shaped with a notch at the top, as shown by the solid line, the chain will come off due to the chain jump actuation torque shown in line C, and the chain will come off due to the chain jump actuation torque shown in line C, which will prevent shock overload. However, as shown by line d, the chain will come off with almost the same torque.

As described above, the present invention provides a grain culm conveying device in which a chain tensioning body with a bullet for tensioning the conveying chain is provided near the driving sprocket for rotating the conveying chain, in which the arc-shaped tops of the teeth of the driving sprocket The section is cut off so that the conveying chain can be removed at the limit torque, and the connection between the rising surface of the tooth and the cut surface is formed at the corner, so of course when the load on the conveying chain increases gradually and becomes overloaded. about,
When an impact overload is applied, the chain roller of the conveying chain reaches its limit torque, and instead of riding on the arc of the top of the drive sprocket's teeth, it comes off at the corner, causing the tip of the tooth to In the conventional type where the chain roller was formed in an arc shape, even if the chain roller was set to come off from the drive sprocket at the limit torque, there were variations in the way the chain roller came off depending on the manner in which the torque increased.However, according to the present invention, when the torque increases gradually, Even if the torque increases rapidly due to culm clogging, etc., the conveying chain can be prevented from coming off the teeth of the drive sprocket with a substantially constant torque, thereby preventing damage to the transmission mechanism and the conveying chain and premature elongation of the conveying chain.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a side view of the front part of the combine harvester, FIG. Figure 3 is a sectional view of the drive section of the lateral transfer chain, Figure 4 is a plan view of the stock transfer chain, Figure 5 is a sectional view of the same drive section, and Figure 6 shows the tooth profile of the drive sprocket. The plan view and FIG. 7 are chain jumping operation torque diagrams. 5...Reaping device, 9...Pulling wheel, 10...Stock base raking chain, 12...Horizontal transfer chain, 13a...
Stock conveyance chain, 17, 25, 40... Drive sprocket.

Claims (1)

[Scope of utility model registration request] In a grain culm conveying device that is provided with a chain tensioning body equipped with a bullet that tensions the conveying chain near a drive sprocket that rotates the conveying chain, the conveying chain is rotated by applying a limit torque to the arc-shaped portion of the top of the teeth of the driving sprocket. A safety device for a grain culm conveying device, characterized in that the tooth is removed so that the teeth are removed, and the connection between the rising surface of the tooth and the cut surface is formed at a corner.