JPH11266689A - Dust discharge fan of thresher - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an efficient type dust discharge fan generating low noise. SOLUTION: In this dust discharge fan, a duct having nearly reverse S-shaped cross section and rotatably horizontally and internally installing an impeller 35 in the lower curved part B is formed and the space between the inside diameter of a cover 41 for covering the impeller 35 in close contact along a part of the outer periphery of the impeller 35 making the curved part B on the lower side of the duct and the outside diameter of the impeller 35 is made to be proportional to the outside diameter D of the impeller 35 and the proportional coefficient is set to 0.08±0.02.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust discharging fan for a threshing machine for discharging dust generated inside a threshing machine outside the machine.

[0002]

2. Description of the Related Art Conventionally, a so-called cross flow fan provided with an impeller in a duct is applied to a dust exhaust fan in a threshing machine provided in a combine or a harvester, and the like. BACKGROUND ART A threshing machine configured to perform uniform air-blowing to perform good sorting is generally known.
The exhaust fan has a substantially inverted S-shaped cross section, and has a structure in which an impeller is rotatably and horizontally mounted inside one of the bent portions of a duct extending in the width direction of the fuselage. It was common that the adjacent opening was used as an outlet for air (dust such as straw) and the other opening was used as a suction port for air (dust such as straw).

At this time, the bent portion of the duct in which the impeller is arranged is configured as a cover for covering the outer diameter of the impeller along the impeller, and an extension portion extending from the cover to the discharge port side. It is known that a stabilizer that stabilizes a relatively strong air vortex generated near the inner periphery of the impeller during operation of the cross flow fan is generally configured by the cover.

[0004] Generally, the narrower the gap between the impeller and the cover, the more aerodynamic performance (air intake and exhaust efficiency as a fan).
It is known that it is advantageous to noise but disadvantageous to noise. When the gap is δ and the outer diameter of the impeller is D, noise and aerodynamic characteristics are compatible (a compromise between the two). ) Δ is set based on the value of δ / D. However, the noise is relatively loud to workers and the like. Therefore, there has been a demand for a cross-flow fan type exhaust fan with lower noise and higher efficiency.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a dust exhaust fan in a threshing machine according to the present invention is provided in a threshing machine 1 with a duct having a substantially inverted S-shaped cross section in a vertical direction with both ends opened. 36, an impeller 35 is rotatably and horizontally mounted inside a curved portion B below the duct 36, an opening below the impeller 35 is used as a discharge port 38, and an upper opening is sucked. A cross-flow type threshing machine dust exhaust fan having an opening 37, wherein a curved portion B on the lower side of the duct 36 constitutes a cover 41 that is closely covered along a part of the outer periphery of the impeller 35, An extension portion 42 extending from the cover 41 to the discharge port 38 and the cover 41 constitute a stabilizer 43 for stabilizing the air vortex of the cross flow fan. The inner diameter of the cover 41 and the impeller 35 The gap δ with the outer diameter of the impeller 5 allowed in proportion to the outer diameter D of, and the proportional coefficient is characterized in that a 0.08 ± 0.02.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a left side view of an automatic feed threshing machine 1 to which the present invention is applied. The threshing machine 1 includes a threshing room 2 for threshing a harvested culm, and a sorting room 5 for sorting the threshed grains. A grain tank 3 for accommodating the grain after the threshing and sorting, and the like. The threshing chamber 2 includes a feed chain 6 for transporting the harvested culm along the handling chamber 4, and a transported grain. Handling cylinder 7 for threshing culms and handling net 8 for leaking material
Are provided.

The handling cylinder 7 and the handling net 8 in the threshing room 2
A processing chamber 23 having a processing drum 21 and a processing net 22 therein is connected to the front end of the processing chamber 23.
And, it is located below the processing chamber 23 by being divided by the handling net 8 and the processing net 22. In addition, a straw conveying body 26 that conveys the threshed culm to the straw cutter 24 installed at the rear is also provided in connection with the end of the feed chain 6.

On the other hand, the sorting room 5 is provided with a Karino fan 11 for generating a sorting wind and a dust discharging fan 12 having a structure to be described later for forcibly discharging dust such as straw waste. A swing sorting body 9 for swinging and sorting the grains leaked by the handling net 8 and the treatment net 22 is mounted in the sorting wind path F formed by the dust exhaust fan 12 so as to swing in the front-rear direction. ing. Further, a first accommodation portion 13 for accommodating the first object selected by the swing sorting body 9 and a second accommodation portion 14 for accommodating the second object are also provided.

Further, in the sorting room 5, the first horizontal spiral 16 for transporting the first object laterally to the end of the first accommodating section 13, and the first object laterally transported to the end is lifted to the grain tank 3. A frying cylinder 17 to be conveyed, a second horizontal helix 18 for horizontally conveying the second product to the end of the second storage unit 14, and a reduction cylinder for returning the second product horizontally conveyed to the end to the swing sorting body 9. 19 etc. are also provided,
In addition, a blower fan 27 that blows a sub-sorting wind from below toward the swing sorting body 9 is provided between the first housing portion 13 and the second housing portion 14.

At this time, the rocking sorter 9 comprises a transfer plate 31 and a chaff sheave 31a between the left and right side plates 9a from the front.
And a sorting net 32a below the chaff sheave 31a.
And a slanted first flow plate 32 for letting the first thing flow down into the first storage portion 13 is provided below the lower end, and a straw rack 33a is protruded from the rear end of the first flow plate 32. And
Below this, a second flow plate 33 for allowing a second object to flow down into the second storage portion 14 is provided obliquely, and these are integrally framed.

The swing sorting body 9 is removably supported at its front and rear sides by a swing link 28 and a support link 29, and can be released from outside the threshing machine 1 from outside. The insertion and removal work can be easily performed. The configuration described above is the same as that of the conventional automatic feed threshing machine, and the threshing machine 1 according to the present embodiment.
Also performs the same threshing, sorting, and grain transport operations as in the past.

Dust (dust) such as straw waste generated inside the threshing machine 1 during the threshing operation continues from the sorting wind path F by the sorting wind formed by the Karamin fan 11 and the dust discharging fan 12. Dust fan 1 is guided along the exhaust air path f
2 and is discharged to the outside of the apparatus from a dust outlet 38 described later. Next, the structure of the dust exhaust fan 12 will be described in detail.

As shown in FIG. 1, the dust exhaust fan 12 is disposed adjacent to and below the rear end side of the second flow plate 33, and substantially in the machine width direction as shown in FIGS. Fan case 3 which is a tubular duct that is installed horizontally across the entire width
6 and a counterclockwise direction (R
Direction), and a large number of curved blades 3
Drum-shaped multi-blade impeller 3 provided with predetermined intervals 5a
5 is provided as a so-called cross-flow fan.

As shown in FIG. 3, a rotating shaft 35b protruding from the axis of the impeller 35 is
The pulley 3 is rotatably supported on the left and right side plates 36a and 36b, and is attached to an end of the rotary shaft 35a.
4, the impeller 35 is rotated integrally with the rotating shaft 35b.

On the other hand, the fan case 36 is opened at the upper end thereof through the dust exhaust passage f, and the dust (air) conveyed by the sorting air from the Karino fan 11 and the blower fan 27.
Curved into a substantially inverted S-shape having an inlet portion 37 serving as a suction port for sucking air, and a dust outlet port 38 serving as a discharge port for discharging dust (air) which opens downward and downward toward the lower end side. It has a box-like shape having a side cross-sectional shape that is squeezed, and is detachably attached to the threshing machine 1 (the swinging sorter 9).

That is, the above-mentioned dust passage f is curved in a substantially inverted S-shape, and the separation wind W from the separation passage F is supplied to the entrance portion of the dust passage f (the inlet portion 37 of the fan case 36). Is drawn along the curved guide portion 39 forming a smooth curve toward the impeller 35 side, is sucked, and shown in FIG. 4 "Theoretical flow of the cross flow fan through which the fluid Y flows through the rotating impeller X. The separation wind W is discharged from the dust outlet 38 in a manner approximating the flow of the "diagram", and the dust is carried on the separation wind W (dust wind) in the dust passage f and the dust is discharged to the dust outlet 38. Is discharged from

The impeller 35 is housed in a curved portion on the lower side of the fan case 36, and the fan case 3
6 is configured as a cover 41 that covers the impeller 35 (part of the outer periphery of the impeller 35) close to the inside of the curve in the lower curved portion B along the outer periphery of the impeller 35. The outer diameter of the car 35 and the inner peripheral surface (inner diameter) of the cover 41
When the gap is δ and the outer diameter of the impeller 35 is D, the gap is proportional to the outer diameter D of the impeller 35 as represented by δ = kD (k is a proportional constant). It is set to be.

Then, k is set to 0.08 ± 0.02. In other words, since D is the outer diameter of the impeller 35, that is, a positive real number, δ is δ / D = 0.08 ± 0.02. 0.0
The value is set so as to satisfy 2. For this reason, the discharge of the dust is easily performed by δ having a relatively large value as compared with the related art. At this time, 0.02 is an error with respect to a predetermined value (0.08) of δ / D.

In addition, the cover 41 and the extending portion 42 of the fan case 36 extending from the cover 41 to the side of the dust outlet 38 and the cover 41 generally generate relatively near the inner periphery of the impeller during the operation of the cross flow fan. Strong air vortex S (see Fig. 4)
Is configured, and the dust exhaust fan 12 of the present embodiment having the stabilizer 43 is configured.
By setting δ in the (cross-flow fan), the vortex is made closer to the stabilizer 43 side, thereby improving the aerodynamic performance (air intake / exhaust efficiency as a fan) and reducing noise.

More specifically, the exhaust fan 12 (impeller 35)
5 (a) and 5 (b) when the rotation speed of the motor is 1500 rpm.
As shown in the figure, the flow rate (air volume) within a certain range (m ³ / min)
The noise {measured noise level Lpa [dB (A)]} and the efficiency η (%) with respect to the fan power (kw) are all improved (reduced noise and increased efficiency) within the measured flow rate. At this time, the solid line N is the measurement result in the present embodiment, and the dotted line O is the measurement result of the conventional exhaust fan, and the noise is significantly reduced.
Sound (secondary and tertiary) noise is reduced. Note that the above measurement is performed at a flow rate in the range of about 20 to 55 m ³ / min, but this flow rate range is almost the range when used as a dust exhaust fan.

As shown in FIGS. 1 and 2, the front peripheral wall 44 of the fan case 36 extends above the impeller 35, and the upper side of the impeller 35 extends along the outer periphery of the impeller 35. Covering relatively close. For this reason, as shown in FIG. 2, the backflow of the exhaust air having an inverted S-shape substantially along the fan case 36, which tends to return to the inlet portion 37 at the suction portion to the impeller 35, is blocked by the peripheral wall 44. Then, it is sent to the exhaust port 38 side.

In other words, the entrance 37 of the exhaust wind is formed by the peripheral wall 44.
The backflow to the side is prevented, and the reduction of the dust exhaust efficiency is prevented. In other words, the front peripheral wall 44 of the fan case 36 is provided with the exhaust wind (when applied to a general cross flow fan) provided on the fan case 36 side. It functions as a shielding part for preventing the backflow of the intake air (inlet air to the impeller side).

On the other hand, as shown in FIG.
A plate-shaped cover member curved along the outer diameter of the impeller 35 that covers the gap t between the left side plate 36a and the end of the impeller 35 is provided on the support side plate (left side plate 36a side) of the impeller 35 in FIG. A rotation shaft 46b is provided so as to protrude above the impeller 35 and is exposed between the left side plate 36a of the fan case 36 and the impeller 35 by the cover member 46.
Is covered on the upper side.

This prevents a trouble that the straw or the like is wrapped around the rotating shaft 35b during operation of the threshing machine 1 (during operation of the dust exhaust fan 12) and the like, and more stable operation of the dust exhaust fan 12 (impeller). 35 rotates stably)
In addition, since the end portion of the impeller 35 is sealed, air leakage from the end portion is reduced, and the aerodynamic performance of the dust discharge fan 12 is also improved.

In the same manner as in the prior art, a wind separator is provided below the sorting net 32a in the swinging sorting body 9 to stabilize the sorting wind by the Karino fan 11 and the like (to increase the wind speed on the windward side of the sorting net 32a as compared with the others). A plate 47 is provided. In the present embodiment, the wind-cutting plate 47 is pivotally supported at its end (front end), and during operation of the threshing machine 1 (during operation of the Karamino fan 11). It is driven so that it can be rocked at a constant cycle (the drive system is not shown).
As a result, the wind speed on the windward side of the sorting net 32a is higher than the other wind speeds, and the dead space near the windless state on the leeward side is reduced, so that the sorting space is further expanded and the sorting efficiency is improved.

[0026]

According to the structure of the present invention configured as described above, the gap δ between the outer diameter of the impeller and the inner diameter of the cover is δ / D
= 0.08 ± 0.02 (where D = the outer diameter of the impeller is a positive real number) because it is set in proportion to the outer diameter of the impeller. Dust and the like are easily discharged, and the noise is reduced, so that there is an effect that a dust discharging fan with relatively high efficiency and low noise can be configured.

[Brief description of the drawings]

FIG. 1 is a left side view of an automatic feeding threshing machine.

FIG. 2 is a side sectional view of a main part of a dust exhaust fan portion.

FIG. 3 is a rear cross-sectional view of a main part of a dust discharge fan portion.

FIG. 4 is a theoretical stream diagram of a cross flow fan.

FIGS. 5A and 5B are graphs showing measurement results of noise and efficiency.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Threshing machine 36 Fan case (duct) 37 Inlet part (suction port) 38 Dust port (discharge port) 41 Cover 42 Extension part 43 Stabilizer δ Gap B Curved part D Outer diameter of impeller

Claims (1)

[Claims] 1. A threshing machine (1) in which a duct (36) having both ends opened and having a substantially inverted S-shaped cross section in the vertical direction is formed, and a curved portion (B) below the duct (36) is formed. The impeller (35) is rotatably mounted horizontally on the inside, and the impeller (3)
5) A dust exhaust fan for a cross-flow threshing machine having a lower opening serving as a discharge port (38) and an upper opening serving as a suction port (37), the lower side of the duct (36). The curved portion (B) forms a cover (41) that covers closely along a part of the outer periphery of the impeller (35), and the cover (4)
1) A stabilizer (43) for stabilizing the vortex of the air of the cross flow fan, comprising an extension (42) extending to the discharge port (38) side and a cover (41). Threshing machine in which the gap (δ) between the inner diameter of (41) and the outer diameter of the impeller (35) is made proportional to the outer diameter (D) of the impeller (35), and the proportional coefficient is 0.08 ± 0.02. Exhaust fan.