JPH04298410A - Screw feeder - Google Patents

Abstract

PURPOSE:To equalize discharge of grain material in the lateral direction at a discharge port for a screw feeder having a pair of transfer screws disposed in parallel. CONSTITUTION:One transfer screw 3a is formed tapered to have a smaller diameter as it goes from one end to the other end, while the other transfer screw 3b is formed tapered to have a larger diameter as it goes from one end to the other end, and by setting one end part of the transfer screw 3a having a large diameter, a cutting quantity of grain material becomes large, thereby the grain material can be discharged uniformly at a discharge port 6 if the grain material moves to the other transfer screw 3b side by rotation of the transfer screw 3a during transfer.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw feeder, and more particularly to a screw feeder in which a pair of conveying screws are arranged in parallel.

0002

2. Description of the Related Art As shown in FIG. 2, a screw feeder is known in which a pair of conveying screws 13a and 13b are arranged in parallel in a discharge section 12 at the lower end of a hopper 11. These conveyance screws 13a, 13b
protrudes laterally from the discharge part 12, and as shown in FIG. 3, the protruding portion is surrounded by a discharge cylinder part 15 which joins casings 14a and 14b having an arcuate cross section. A discharge port 16 is opened at the bottom of the distal end of the discharge cylinder portion 15 and extends across both conveying screws 13a and 13b. One end of each conveyance screw 13a, 13b is rotatably supported by a bearing 17 provided on the side surface of the discharge section 12, and a driven sprocket 18 driven by a drive means (not shown) is fixed thereto. Further, the other end of each conveying screw 13a, 13b is rotatably supported by a bearing portion 19 provided on the side surface of the discharge cylinder portion 15.

0003

However, in the screw feeder having the above-mentioned configuration, as shown in FIG. In the lower part, the granular material 20 of the object to be transported moves from the upper transport screw 13a in the rotational direction toward the lower transport screw 13b as shown by arrow B as the transport screws 13a and 13b rotate. There was a problem in that the amount of powder and granular material 20 discharged from the discharge port 16 was larger on the conveying screw 13b side, and the powder and granular material 20 was discharged unevenly, and was not uniformly discharged from the entire width of the discharge port 16.

In view of the above-mentioned conventional problems, the present invention provides a screw feeder in which powder and granules are uniformly discharged in the width direction of the screw feeder in which conveying screws are arranged in parallel. The purpose is to provide.

[0005]

[Means for Solving the Problems] The present invention provides a screw feeder in which a pair of conveyance screws are arranged in parallel, in which the outer diameter of one conveyance screw becomes gradually smaller from one end to the other end, and the outer diameter of one conveyance screw becomes gradually smaller from one end to the other end. The outer diameter of the conveyance screw is tapered so that the diameter gradually increases from one end to the other end.

[0006]

[Operation] According to the structure of the present invention, since the conveying screws tapered in opposite directions are arranged in parallel,
At the bottom of these transport screws, the transport screw located on the upper side in the direction of rotation has a larger diameter on the upper side in the transport direction and smaller diameter on the lower side, and the transport screw located on the lower side in the direction of rotation has a smaller diameter on the upper side in the transport direction and a larger diameter on the lower side. By arranging the conveyance screws so that the conveyance screws have a larger diameter, the diameter of the conveyance screw located on the upper side in the rotation direction is larger, so more granules can be cut out than the conveyance screw located on the lower side in the rotation direction. As a result, even if the granular material moves from the upper transport screw in the rotational direction to the lower transport screw during transport, the granular material can be uniformly discharged in the width direction at the discharge port. can.

[0007]

Embodiment An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, a pair of conveying screws 3a and 3b are arranged in parallel in a discharge section 2 at the lower end of a hopper 1. These conveying screws 3a and 3b protrude laterally from the discharge section 2, and the protruding portion is surrounded by a discharge cylinder section 5 in which casings 4a and 4b having an arcuate cross section are joined together. A discharge port 6 is provided at the bottom of the distal end of the discharge tube portion 5 over both conveying screws 3a and 3b.
is opened.

One conveying screw 3a has screw blades 31a on the outer periphery of a tapered drum 30a whose diameter gradually decreases from one end on the discharge section 2 side to the other end on the discharge cylinder section 5 side.
The other conveyance screw 3b has a tapered drum 30 whose diameter gradually increases from one end to the other end.
A screw blade 31b is attached to the outer periphery of the screw blade 31b. These conveyance screws 3a and 3b have a conveyance screw 3a on the upper side in the rotational direction at the bottom thereof.
is arranged, and a conveyance screw 3b is disposed on the lower side in the rotational direction, and in the discharge section 2, the conveyance screw 3a on the upper side in the rotational direction has a large diameter, and the conveyance screw 3b on the lower side in the rotational direction has a small diameter. ing.

One end of each conveyance screw 3a, 3b is rotatably supported by a bearing 7 provided on the side surface of the discharge section 2, and a driven sprocket 8 driven by a drive means (not shown) is fixed thereto. ing. Further, the other end of each conveying screw 3a, 3b is rotatably supported by a bearing 9 provided on the side surface of the discharge tube 5.

According to the above configuration, when the driven sprockets 4a and 4b are rotationally driven by the driving means (not shown),
The conveying screws 3a and 3b rotate, and the powder and granules in the hopper 1 are discharged from the conveying screws 3a at the lower end of the discharge section 2.
, 3b, and is transported toward the discharge port 6 at the tip of the discharge cylinder section 2 and discharged.

[0011] At this time, since the conveying screw 3a located on the upper side in the rotational direction in the discharge section 2 on the upper side in the conveying direction has a larger diameter, more granules can be cut out than the conveying screw 3b on the lower side. can. Therefore, even if the granular material moves from the upper conveying screw 3a in the rotational direction toward the lower screw 3b during conveyance by these conveying screws 3a and 3b, it is uniform in the width direction at the discharge port 6. The granules can be discharged.

0012

[Effect of the invention] According to the screw feeder of the present invention,
As mentioned above, since the conveyance screws tapered in opposite directions are arranged in parallel, the conveyance screw located on the upper side in the rotational direction at the bottom of these conveyance screws has a larger diameter on the upper side in the conveyance direction and has a lower diameter on the upper side in the conveyance direction. By arranging the conveyance screw located on the lower side in the rotational direction so that the upper side in the conveyance direction has a small diameter and the lower side has a larger diameter, Because the conveying screw has a large diameter, it can cut out more granules than the conveying screw on the lower side.
Therefore, even if the granular material moves from the upper transport screw in the rotational direction toward the lower screw during transport, the granular material can be uniformly discharged in the width direction at the discharge port.

[Brief explanation of drawings]

FIG. 1 is a plan view of an embodiment of a screw feeder of the present invention.

FIG. 2 is a plan view of a conventional screw feeder.

FIG. 3 is a cross-sectional side view taken along line A-A in FIG. 2;

[Explanation of symbols]

3a　Transportation screw 3b Conveyance screw

Claims (1)

[Claims] Claim 1: In a screw feeder in which a pair of conveyance screws are arranged in parallel, the outer diameter of one conveyance screw becomes gradually smaller from one end toward the other end,
A screw feeder characterized in that the outer diameter of the other conveying screw is tapered so that the diameter gradually increases from one end to the other end.