JP2001299064A - Grain-discharging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grain-discharging apparatus where an auger is lightened while maintaining the grain-conveying performance of the auger in such a way as to be equal to or higher than that of a conventional auger. SOLUTION: This grain-discharging apparatus possesses a retractable tube body composed of a combination consisting of one or more fixed conveyance tubes and a movable conveyance tube, plural retractable screw units 17 placed within the retractable tube and for conveying grains and plural inextensible fixed screw units, and at least parts of the retractable screw units 17 are made of a synthetic resin and the inextensible fixed screw units are made of a metal. Since the screw units 17 of a grain-discharging auger 5 are synthetically resinified, the auger 5 is lightened, the moment of the auger 5 itself is decreased to enable smooth turning and vertical movement by small driving force, and costs can be cut in comparison with the screw units made of the metal such as a ferrous metal, and unevenness in quality is eliminated to enable smooth extension and contraction and/or smooth discharge.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grain discharging device such as a combine or a grain carrier.

[0002]

2. Description of the Related Art A conventional grain discharge device for a combine, as disclosed in the prior invention (Japanese Patent Laid-Open No. 9-54) of the present applicant, shown in FIG. A bottom spiral 10 for conveying kernels in a horizontal direction, a kernel 4 connected to the bottom spiral 10 for conveying kernels in a vertical direction, and rotatable around a vertical axis; 4, a grain discharging auger 5 comprising a fixed transporting cylinder 6 and a movable transporting cylinder 7 which transports the grain in the horizontal direction, is vertically movable up and down, and is zoomable in the longitudinal direction. I have.

In order to arrange the auger discharge port 9 at a position where the auger discharges at the time of the threshing operation, the raising cylinder 4 is turned, the fixed transport cylinder 6 and the movable transport cylinder 7 are moved up and down, and the movable transport cylinder is moved. 7
When zooming or zooming is shortened, and when a threshing operation is not performed, such as during a harvesting operation or running on a road, the movable transport cylinder 7 is zoomed down and is seated and stored in the auger receiver 35 on the combine.

[0004]

In the conventional combine combiner, during the dumping operation by the dumping auger 5, the fixed transfer tube 6 and the movable transfer tube 7 are moved up and down, and the movable transfer tube 7 is expanded or shortened. Grains are discharged from the auger discharge port 9, and at this time, the grains are sequentially conveyed toward the auger discharge port 9 by rotation of a spiral 14 provided in the fixed transfer tube 6 and the movable transfer tube 7.

However, the metal helix 14 is heavy, increases the weight of the entire auger, places a large load on the drive source for turning and extending and retracting the auger, and also causes the cylinder to only support the heavy metal helix. It needed to be a sturdy structure.

[0006] By making at least the spiral of the auger made of a synthetic resin, the weight of the auger can be reduced. However, conventionally, the spiral made of the synthetic resin cannot provide sufficient strength for transporting kernels.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a grain discharging device in which the auger is reduced in weight while maintaining the auger's grain conveying performance equal to or higher than the conventional one.

[0008]

The object of the present invention is solved by the following constitution. (1) In a grain discharging device provided with an auger having a telescopic spiral for discharging grains therein, an extensible tubular body comprising a combination of at least one fixed transporting tube and a movable transporting tube, Equipped with a plurality of extensible single spirals for grain transport and a plurality of fixed non-extendable fixed spirals disposed inside the body, at least a part of the extensible single spirals is made of synthetic resin, and the non-extendable fixed single spiral is made of metal And grain discharging device. (2) In a grain discharging device provided with an auger having a telescopic spiral for discharging grains therein, an extensible tubular body composed of a combination of at least one fixed transporting tube and a movable transporting tube; Equipped with a plurality of extensible single spirals for grain transport and a plurality of non-extendable fixed spirals arranged inside the body, both the extensible single spirals and the non-extendable fixed single spirals, at least a part of which is made of synthetic resin Grain discharging device.

[0009]

Conventionally, the spiral simplex 17 of the dumping auger 5 (FIG. 5)
Was made of iron-based metal, but when the augmenting auger's moment increased, not only did it require a large driving force, but there was also a drawback that the quality of the finished product due to its processing and welding varied, and it was also expensive. Had become something.

In the present invention, the spiraling auger 5 is made lighter by converting the spiral single piece 17 into a synthetic resin. In addition, since the moment of the auger auger 5 itself is reduced, smooth turning and up / down movement can be performed with a small driving force. In addition, by converting the spiral single piece 17 into a synthetic resin, the cost can be reduced as compared with a metal made of iron or the like, and there is no variation in quality, and smooth expansion and contraction and discharge can be performed.

In particular, when the kernel sent from the fixed transport cylinder 6 is clogged in the movable transport cylinder 7, the spiral single bodies at the start end and the end of the plurality of spiral simplexes 17 in the movable transport cylinder 7. 17
Since a large load is applied to the spiral, the spiral single body 17 on the start end side and the terminal end side is made of, for example, a synthetic resin containing glass fiber, and the other spiral single body 17 in the middle part is made of an ordinary synthetic resin. This is advantageous in cost and has high durability.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a left side view of the combine of the present invention, FIG. 2 is a front view of the combine, and FIG. 3 is a right side view of the combine. FIG. 4 is a view for explaining the structure of an auger part for dumping a combine.

The outline of the function of the combine will be described with reference to FIGS. The combine is provided with a cockpit 40 on a chassis 2 having a crawler 1, and an operator operates and operates the cockpit 40 to cut a culm to be planted in a field, a cutting device 34, and the cut culm. Threshing device 37 for threshing this after transporting the
A grain tank 3 for accommodating threshed grains, a grain discharging auger 5 for transporting grains discharged backward by a bottom spiral 10 (FIG. 4) provided at the bottom of the grain tank 3 to the outside of the combine, and the like. Is done.

[0014] The dumping auger 5 is connected to the rear end of the bottom spiral 10 and transported upward, and is connected to the lifting cylinder 4. The fixed transporting cylinder 6, which transports the grains in the horizontal direction, It is composed of a movable transfer cylinder 7 and the like. An auger outlet 9 is provided at the tip of the movable transfer cylinder 7.

The combine shown in FIG. 1 has a pair of left and right crawlers 1 formed of a flexible material such as rubber as an endless band at a lower portion of a chassis 2, and includes not only dry fields,
In the wetland, a crawler 1 is provided with a traveling device that can travel freely only by slightly sinking, a reaper 34 is mounted on the front of the chassis 2, and an engine (not shown) and a Glen tank 3, Threshing device 37, cockpit 4
0 is provided.

The grains stored in the grain tank 3 of the combine are discharged from the bottom spiral 10, but the bottom spiral 10
As shown in FIG. 4, a shaft is provided at the bottom of the Glen tank 3, the starting end is connected to a transmission shaft 11 outside the machine via a clutch device 12, and the end is extended to the lower part of the fryer 4. And is connected to the lower end of the fried spiral 13 that is housed inside.

The dumping auger 5 (FIG. 4) is composed of a fixed transporting cylinder 6 connected to the upper part of the above-mentioned fryer cylinder 4 so as to be vertically movable and a movable transporting cylinder 7 connected thereto. However, the configuration will be specifically described below.

First, as shown in FIG. 4, the fixed transfer cylinder 6 has a base connected to the upper part of the frying cylinder 4 and a distal end extended outwardly. Is internally provided with a transport spiral 14 connected to the above-mentioned frying spiral 13 to transport the grains inherited from the frying cylinder 4.

As shown in FIG. 4, the movable transfer cylinder 7 is provided with an auger discharge port 9 opened at the front end thereof, and the base side is inserted and fitted from the front end side of the fixed transfer cylinder 6 so that it can slide freely. I'm relocated. Also, as shown in FIG. 4, the telescopic spiral 15 has a front end bearing above the auger discharge port 9 and a rear end extending toward the fixed conveying cylinder 6 in the movable conveying cylinder 7 so that the shaft of the conveying spiral 14 can be extended. A transmission shaft 16 slidably inserted into the shaft is provided on a shaft, and a large number of spiral single bodies 17 (FIG. 5) are slidably fitted to the transmission shaft 16 so that the mutual interval can be adjusted. are doing.

Further, as shown in FIG.
3 is a telescopic control motor 24 mounted at the upper position of the fryer 4
And the base end of the helical shaft 25 is connected via a speed reducer to forcibly drive. Then, the moving device 26 is connected to the helical groove of the helical shaft 25 via a transmission pin engaged with the helical groove.
It is provided so as to be forcibly moved in the axial direction, and is integrally connected to the base side of the fixed transfer tube 6.

As shown in FIG. 4, the telescopic drive unit 23 has limit sensors S1 and S2 on the most contracted side and the most extended side of the dumping auger 5, respectively. When reaching the limit sensor S2, the telescopic control motor 24 is automatically stopped.

Although the position of the tip of the movable transfer cylinder 7 can be changed in various ways, the position of the tip of the dumping auger 5 is often stored in the auger receiver 35 at an intermediate position of the length of the zoom auger. .

The telescopic control motor 24 is provided with a cockpit 40
Is driven in the forward or reverse direction to rotate the helical shaft 25 based on the ON operation of a switch (telescopic switch) provided on an operation panel (not shown) of the helical shaft 2.
When the rotation of 5 is normal, the movable transfer cylinder 7 is extended via the moving device 26 engaged, and when the rotation is reversed, the movable transfer cylinder 7 is forcibly moved in the reduction direction.

In this manner, the movable transfer tube 7 is extended and contracted along the fixed transfer tube 6 in a state of being fitted to the fixed transfer tube 6, and the position of the auger discharge port 9 at the front end is adjusted. It is configured such that the falling position of the grain can be selected by adjusting the distance from or approaching to the frying cylinder 4 at the base.

In FIG. 4, the lifting hydraulic cylinder 2
7 raises and lowers the dumping auger 5, and the turning motor 28 turns the lifting cylinder 4 via a drive gear 30 provided on the outer peripheral portion of the lifting cylinder 4 that meshes with a rotation gear 29 provided on the rotating shaft. Do.

As shown in FIG. 4, the support roller 31 is provided below the base of the movable transfer cylinder 7 so as to be supported by a shaft, and supports the peripheral surface of the fixed transfer cylinder 6 while rolling. Further, a guide wheel 32 is provided above the base position of the movable transfer tube 7, and a guide rail (not shown) for guiding the guide wheel 32 is provided in the longitudinal direction of the fixed transfer tube 6.

When the combine constructed as described above is advanced while being operated, the planted grain culm is cut off by the reaper 34 (FIG. 1) as a combine operation, and then transported to the starting end of the threshing device 37. And threshing while being conveyed by the feed chain 38. Threshing device 37
The grains selected by threshing are temporarily stored in the Glen tank 3, and when the grains in the Glen tank 3 are full, the grain discharging auger 5 is detached from the auger receiver 35 (FIG. 4), and The grains are discharged from the grain auger 5 to a bed such as a truck.

At this time, if the position of the auger discharge port 9 is short, the moving and transporting cylinder 7 is extended to discharge the grains farther away. In addition, the movable transport cylinder 7 is expanded and contracted so that the grains are uniformly discharged to the truck bed.
When the grain in the Glen tank 3 is discharged in this way, the discharged auger 5 is stored in the auger receiver 35 again.

The telescopic spiral 15 of the movable transfer cylinder 7 shown in FIG. 4 comprises a plurality of spiral single bodies 17 made of synthetic resin. FIG.
Shows a perspective view of the spiral single body 17. FIG. 6 shows a single spiral 1
7 shows a perspective view from another angle of FIG. FIG. 7 shows a side view of the telescopic spiral 15 in the state most distant from each other while the plurality of spiral single bodies 17 are connected, and FIG. 8 shows the plurality of spiral single bodies 17 approaching each other while being connected. The side view which comprises the expansion-contraction spiral 15 of a state is shown.

As shown in FIGS. 5 and 6, the spiral single body 17 has a cylindrical bearing boss 18 whose outer peripheral portion is slidably fitted to the transmission shaft 16 (FIG. 7), and is supported and fixed to the outer peripheral surface thereof. And
The spiral helical body 20 is formed around the outer periphery of the bearing boss 18 substantially, and a spacer 19 for connecting the spiral body 20 to the bearing boss 18. Spacer 19 is the bearing boss 1
A spiral body 20 is connected and fixed to both ends of the outer peripheral surface of the coil 8 at substantially both ends thereof. The spacer 19 constitutes a connecting portion for connecting and fixing the spiral body 20 to the bearing boss 18, and is configured to be able to move away from or approach to each other while connecting the plurality of spiral single bodies 17.

For this reason, the spacer 19 is formed in a spiral shape so as to make substantially one round around the outer periphery of the bearing boss 18 as in the case of the spiral body 20. As shown in FIG. When in the closed state, the thick portions 19a (FIG. 5) of the spacers 19 adjacent to each other can be engaged with each other. Also, the bearing boss 18
As shown in FIG. 5, the length A is about half of the length B of the spacer 19, and the inner diameter of the spacer 19 is
Is slightly larger than the outer diameter of
7, when the spiral body 20 comes closest to the adjacent spiral body 20, as shown in FIG. At this time, the grains between the outer periphery of the bearing boss 18 and the inner periphery of the spacer 19 can escape to the outside through the hole 19b provided in the spacer 19.

Further, since the lower surface of the thick portion 19a for engagement of the adjacent spacer 19 is formed in a round shape, the strength is increased. Further, since the spacer 19 is provided between the bearing boss 18 and the helical body 20 in a spiral shape so as to substantially make a full circle around the outer periphery of the bearing boss 18 like the helical body 20.
The use of a resin for the spiral single piece 17 can also compensate for the reduced strength as compared with a metal spiral.

The spiral single body 17 having the above-described configuration is fitted in the transmission shaft 16 having a rectangular axis in the rotation direction, and is fitted in the axial direction so as to be freely slidable. It constitutes a series of telescopic spirals 15.

In the auger auger 5 composed of the fixed transport cylinder 6 and the movable transport cylinder 7, at least the spiral single piece 17 in the movable movable transport cylinder 7 is made of a synthetic resin. Therefore, the portion of the fixed transfer cylinder 6 may be made of metal.

In this case, by making the spiral single body 17 in the movable transfer cylinder 7 that extends and contracts the dumping auger 5 made of synthetic resin, the tip of the dumping auger 5 that has a large influence on the moment of inertia of the entire dumping auger 5 is made. The weight of the portion is reduced, and the effect of reducing the weight of the waste auger 5 is great.

However, not only the expanding and contracting spiral part but also the fixed spiral part can be made of synthetic resin. In this case, especially when the auger 5 is increased in size, an effect of reducing the weight is obtained, and the burden on not only the auger 5 but also other components of the combine can be reduced.

The spiral spiral body 20 of the spiral single body 17 may be made of either synthetic resin or metal, as shown in FIG.
As shown in the side view of the spiral simplex 17, the spiral of the spiral body 20 of the spiral simplex 17 can start from the central axis X in side view, make a round around the central axis and end at the central axis X. Spiral simplex 1 shown in FIGS. 5 to 8
7, the start end and the end of the spiral-shaped portion of the spiral body 20 of the spiral simplex 17 are longer than the center axis X of the spiral simplex 17 by a length L when the spiral simplex 17 is viewed from the side as shown in FIG. The portion longer by the length L does not fall out of the mold. Therefore, it is necessary to provide another movable mold at a portion longer by the length L, and the mold is complicated and expensive.

However, in the embodiment shown in FIG. 9, since the spiral of the spiral body 20 of the spiral single body 17 ends up to the central axis X in side view as described above, the die does not undercut. As a result, the spiral simplex 1 shown in FIG.
The mold 7 is simple and inexpensive.

In the present invention, by making the spiral simple substance 17 a synthetic resin, the weight reduction auger 5 can be reduced in weight. Also, since the moment of the auger auger 5 itself is reduced, smooth turning,
Up and down movement is possible with a small driving force. In addition, by converting the spiral single piece 17 into a synthetic resin, the cost can be reduced as compared with a metal made of iron or the like, and there is no variation in quality, and smooth expansion and contraction and discharge can be performed.

In particular, when the grain is easily clogged at the start end of the movable transport cylinder 7 that takes over the grain from the fixed transport cylinder 6 and the end portion (the grain discharge port) that discharges the grain to the outside, the kernel is clogged. Since a large load is applied to the spiral unit 17, the spiral units 17 on the starting end side and the terminal end side in the plurality of spiral units 17
Is made of, for example, a synthetic resin containing glass fiber, and the other spiral unit 17 at the intermediate portion is made of an ordinary synthetic resin, which is advantageous in cost and has high durability.

At the grain transfer section from the fixed transfer tube 6 to the movable transfer tube 7, a metal for holding the fixed spiral 14 and the transmission shaft 16 in the fixed transfer tube 6 is provided.
Certain grain-free zones occur. For this reason, the grain may temporarily stagnate in this portion, and smooth conveyance may not be possible.

Therefore, as shown in FIG. 10, the spiral diameter (D) of the spiral single body 17 of the grain transfer section of the movable transport cylinder 7 is shown.
Is larger than the helical diameter (d) of the helical unit 17 in the other part (D> d). In this way, the amount of grain transported in the grain transfer section is made larger than in the other sections, thereby preventing the grain from temporarily stagnating in this section.

The moving and conveying cylinder 7 of the dumping auger 5 shown in FIG.
In the plurality of spiral single bodies 17 provided in the above, only the spiral single body 17 at the front end and the rear end is made of metal, and other spiral single bodies 1
7 may be made of a synthetic resin.

Also in this case, the flesh auger 5 can be reduced in weight and the moment of the flesh auger 5 itself is reduced, so that smooth turning and up-and-down motion can be performed with a small driving force. Also,
By converting the spiral single body 17 into a synthetic resin, the cost can be significantly reduced as compared with the metal spiral single body 17. In addition, there is no variation in the quality of the spiral single piece 17, and smooth expansion and contraction and discharge become possible. However, the spiral single piece 17 at the end of the movable transfer cylinder 7 which receives a large load when the grain is clogged, and the grain transfer transfer section from the fixed transfer cylinder 6 to the movable transfer cylinder 7 are made of metal because the wear is large. Is desirable.

The hexagonal hole 42 'formed in the central shaft portion of the bearing boss 18 of the metal spiral unit 17 is manufactured in the following procedure. First, as shown in FIG. 12, a cylindrical pilot hole 42 "having substantially the same diameter as a hexagon hole 42 'to be formed later is previously formed in the center shaft portion of the bearing boss 18 in advance, and the same hole as the pilot hole 42" is formed. A broach 41 having a diameter is inserted to form a hexagonal hole 42 '.

Accordingly, even after the hexagonal hole 42 'is formed, the cylindrical pilot hole remains, so that the transmission shaft 16 is connected to the hexagonal hole 4'.
Even after insertion into the 2 ', dust easily entered the interior of the pilot hole where the bearing boss 18 remained, which had an adverse effect on slidability.

In the present invention, since the plurality of synthetic resin spirals 17 provided in the movable transfer cylinder 7 are integrally formed of synthetic resin, they are formed when the hexagonal holes 42 (FIG. 6) of the bearing boss 18 are integrally formed. I'm sorry. Therefore, unlike the case of the metal spiral unit 17, a pilot hole such as when the hexagonal hole 42 (FIG. 6) of the bearing boss 18 is formed cannot be formed. For this reason, in the spiral unit 17 made of synthetic resin, the transmission shaft 16 can be inserted into the hexagonal hole 42 without a gap, and the driving surface of the spiral unit 17 becomes large.
In addition, since the force is evenly applied to the hexagonal hole 42, the durability of the bearing boss 18 is improved, and the spiral single body 17 is reliably driven.
Grain can be discharged smoothly.

On the other hand, even if the spiral single body 17 is made of synthetic resin, the bearing boss 1 having the sectional shape shown in FIG.
8, the area of contact with the transmission shaft 16 is reduced, and the sliding resistance when the movable transfer cylinder 7 moves (when the telescopic spiral 15 expands and contracts) decreases, In some cases, smooth operation can be achieved. However, at this time, even after the transmission shaft 16 is inserted into the hexagonal hole, dust easily enters the inside of the pilot hole remaining in the bearing boss 18, and thus it is necessary to keep the transmission shaft 16 always clean.

As shown in FIG. 14, the spacer 19 of the synthetic resin spiral unit 17 of the present invention extends from the connection portion (point A) of the bearing boss 18 to the end connection portion (point B) of the spiral body 20. Increase the inner diameter sequentially. That is, the length h of the point A from the center axis X is the length H (H> H) at the point B.
h). Therefore, when the spiral single body 17 is molded, the spiral single body 17 can be easily removed from the mold.

The spiral 14 in the fixed transport cylinder 6 may be made of a metal such as iron, but the movable transport cylinder 7 itself is made of synthetic resin in the same manner as the single spiral 17 so that the movable transport cylinder 7 Weight is reduced, compared to the case of iron-based
Even when the movable transport cylinder 7 is extended, the center of gravity of the auger 5 is close to the fulcrum, so that the up and down, rotation, and the like of the auger 5 are smooth. At this time, since the fixed transfer cylinder 6 is made of an iron-based material, the rigidity of the waste discharging auger 5 itself can be sufficiently secured, and there is also an effect of reducing the weight of the whole waste discharging auger 5.

[Brief description of the drawings]

FIG. 1 is a left side view of a combine according to an embodiment of the present invention.

FIG. 2 is a front view of the combine shown in FIG. 1;

FIG. 3 is a right side view of the combine shown in FIG. 1;

FIG. 4 is a view for explaining the structure of an auger part for dumping of the combine shown in FIG. 1;

FIG. 5 is a perspective view of a spiral single unit of the waste auger of the combine shown in FIG. 1;

FIG. 6 is a perspective view of the spiral unit of the waste auger of the combine shown in FIG. 1 as viewed from another angle.

FIG. 7 is a side view showing a plurality of spiral single bodies of the waste auger of the combine shown in FIG.

FIG. 8 is a side view of a telescopic spiral in a state where a plurality of spiral single bodies of the waste auger of the combine in FIG. 1 are closest to each other.

FIG. 9 is a side view of the spiral single body of the waste auger of the combine shown in FIG. 1;

10 shows an example (D) in which the spiral diameter (D) of the single spiral of the grain transfer unit of the moving and transporting cylinder of the grain discharging auger of the combine shown in FIG. 1 is larger than the spiral diameter (d) of the single spiral of the other part.
FIG. 6 is a side sectional view showing> d).

11 is a side sectional view in which only the spiral single body at the leading end and the rear end in the moving and transporting cylinder of the grain discharging auger of the combine in FIG. 1 is made of metal, and the other spiral single body is made of synthetic resin.

FIG. 12 is a view for explaining a procedure for producing a hexagonal hole formed in a central shaft portion of a bearing boss of a metal spiral unit of the waste auger of the combine in FIG. 1; .

13 is a side view of the spiral single body showing a shape for inserting the transmission shaft of the bearing boss of the synthetic resin spiral single body of the waste auger of the combine shown in FIG. 1;

14 is a partial cross-sectional view of a spacer portion of a spiral unit made of synthetic resin of a waste auger of the combine shown in FIG. 1;

FIG. 15 is a side view of the spiral single body of FIGS. 5 to 8;

FIG. 16 is a side view of a conventional combine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crawler 2 Undercarriage 3 Glen tank 4 Lifting cylinder 5 Draining auger 6 Fixed transporting cylinder 7 Moving transporting cylinder 9 Auger outlet 10 Bottom spiral 11 Transmission shaft 12 Clutch device 13 Lifting spiral 14 Transport spiral 15 Telescopic spiral 16 Transmission shaft 17 Spiral unit 18 Bearing boss 19 Spacer 19a Spacer thick portion 19b Hole 20 Spiral body 34 Cutting device 35 Auger receiver 37 Threshing device 40 Pilot 41 Broach 42, 42 'Hexagon hole 42 "pilot hole

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Hiroya Uchida 1-Family Yachikura, Tobe-cho, Iyo-gun, Ehime Pref. MA07 MC02 MC13

Claims (3)

[Claims] 1. A grain discharging device provided with an auger having a telescopic spiral for discharging grains therein, comprising: a telescopic cylinder body comprising a combination of at least one fixed transport cylinder and a movable transport cylinder; A plurality of extensible single spirals for grain transport and a plurality of non-extensible fixed spirals arranged in the cylinder are provided. The plurality of extensible single spirals are made of synthetic resin, and the non-extendable fixed spirals are metal. And a grain discharging device. 2. The grain discharging device according to claim 1, wherein the spiral unit at the start end and the terminal unit of the plurality of expandable and contractible spiral units is made of fiber-reinforced synthetic resin. 3. A grain discharging device provided with an auger having a telescopic spiral for discharging grains inside, comprising: a telescopic cylinder body comprising a combination of at least one fixed transport cylinder and a movable transport cylinder; It is provided with a plurality of extensible single spirals for grain transport and a plurality of non-extensible fixed spirals arranged in the cylinder, wherein both the extensible single spirals and the non-extendable fixed single spirals are made of synthetic resin. And grain discharging device.