JPH043999Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a hopper for feeding powder and granular materials for transportation, measurement, etc., and more specifically relates to a hopper that can prevent the bridging phenomenon of powder and granular materials.

[Prior Art] For example, when supplying powdered resin as a raw material to an extrusion molding machine, a hopper is placed at the top of the cylinder of the extrusion molding machine so that the powdered resin naturally falls from the opening at the bottom of the hopper to the inlet of the cylinder. It is configured. However, if the powdered resin contains water, has a large aspect ratio, or if the plasticizer or the like tends to bleed, a bridging phenomenon may occur in the hopper. When such a bridging phenomenon occurs, the supply of powdered resin becomes unstable and the quality of the molded product deteriorates, or in extreme cases, the powdered resin is not supplied and molding becomes impossible.

Various attempts have been made to prevent this bridging. For example, Japanese Utility Model Publication No. 56-31991 discloses a device which prevents bridging by providing a vibrator outside the hopper and imparting impact vibrations to the hopper wall surface. A method of applying vibration to the hopper wall surface using a vibrator is also well known.

In addition, Japanese Patent Publication No. 61-40162 discloses a conventional technology that is equipped with a rotating blade-like stirring device inside the hopper, and furthermore, this publication discloses that the hopper is oscillated by the movement of the screw flight of an extrusion molding machine, etc. Discloses an apparatus for stirring powdered resin.

[Problems to be Solved by the Invention] The above-mentioned device for preventing bridging by vibration may have an adverse effect on the operation of a molding machine, etc., and the reliability of the bridging prevention performance is also poor. Furthermore, if rotating blades or the like are provided, bridging often occurs at locations where there are no blades, such as at the bottom of the hopper.

The present invention provides a hopper that reliably prevents bridging by having a new configuration different from the above-described devices.

[Means for Solving the Problems] The hopper of the present invention has a container shape and has a raw material supply opening that opens at the lower end and an inclined surface that slopes so that the cross-sectional area gradually decreases toward the opening. A hopper body, a plurality of stirring plates provided along the inclined surface, extending from above toward the opening, and arranged in parallel rows at intervals from each other in the horizontal direction; It is characterized by comprising a drive device that reciprocates in parallel.

The hopper body has an opening and an inclined surface. The inclined surface is usually formed by the inner wall surface of the hopper body, and only one inner wall surface may be an inclined surface and the remaining inner wall surfaces may be all vertical surfaces, or each of a pair of opposing inner wall surfaces may be an inclined surface. .

The most distinctive feature of the present invention is the provision of a stirring plate that reciprocates along an inclined surface. The bridging phenomenon is more likely to occur at the lower part of the hopper body where the flow cross-sectional area of the powder or granular material charged into the hopper body is the narrowest, that is, the part along the slope. Therefore, in the present invention, a stirring plate is provided along the slope, and this stirring plate is moved back and forth to prevent bridging.

The stirring plate is provided so as to extend from above the slope toward the opening at the bottom. In order to reliably prevent bridging, it is preferable that it extends to the opening, more preferably to the extent that it protrudes into the opening.

To prevent bridging, it is desirable to simultaneously stir the entire slope. However, if the number of stirring plates is small, the distance of reciprocating movement becomes long, and the waiting time between one stirring and the next stirring becomes long, and bridging may occur during that time. Therefore, although the number of stirring plates is not particularly limited, it is desirable that a plurality of stirring plates be arranged in a row at intervals in the horizontal direction, and that all of the stirring plates are driven at the same time. In this way, by reciprocating the distance corresponding to the length of the interval, it is possible to simultaneously stir the entire slope, and the waiting time between stirring and stirring becomes longer. Bridging can be reliably prevented and the load on the drive device can be reduced. Further, it is preferable that the thickness of the stirring plate is thinner, since the resistance received during driving is smaller. The shape, pitch, number, distance of reciprocating movement, etc. of this stirring plate may be varied depending on the type of powder, specific gravity, etc., and should be determined by trial and error.

The drive device is for reciprocating the stirring plate along the inclined surface, and various conventionally known devices such as a cylinder device can be used. This reciprocating movement may be continuous or may be performed intermittently.
Further, in the case where stirring plates are provided on each of a pair of opposing inclined surfaces, it is preferable to drive the opposing stirring plates alternately. In this way, twisting force acts on the powder and granules, further preventing bridging.

[Operations and Effects of the Invention] In the hopper of the present invention, the stirring plate is reciprocated in the horizontal direction along the inclined surface of the hopper body, so the powder and granules accumulated on the inclined surface are agitated by the stirring plate. , bridging is prevented. Further, since the stirring plate is plate-shaped, it does not become an obstacle to the natural falling of the powder and granules, and the resistance received from the powder and granules during driving is small, so the burden on the driving device is small.

Furthermore, by arranging stirring plates horizontally at intervals and driving them all at the same time, it is possible to stir the entire slope at the same time by reciprocating by the distance. The waiting time until stirring is shortened, and bridging can be prevented extremely efficiently.

Therefore, according to the hopper of the present invention, bridging can be reliably prevented without the adverse effects of vibration and without the agitation plate interfering with the natural falling of the powder or granules.

[Example] This will be explained in detail below using examples.

1 and 2 show a hopper according to an embodiment of the present invention. A feed screw is provided at the bottom of the hopper to gradually feed out the powdered resin supplied by natural fall from the hopper. Note that as the powdered resin, vinyl chloride resin with an average particle size of 120 μm is used.

This hopper is composed of a hopper body 1, a plurality of stirring plates 2, a drive device 3, and a feed screw 4 that is rotationally driven by a motor 5.

The hopper main body 1 is shaped like a container and has a raw material supply opening 10 that opens at the lower end, and a pair of inclined surfaces 11 and 12 that face each other and are inclined so that the volume gradually decreases toward the opening 10.

The stirring plate 2 has a substantially rectangular shape, and its upper end is swingably supported at a distance from horizontally extending shafts 21 and 22, and its lower end is rotated by its own weight to the inclined surface 1.
1 and 12. The shafts 21 and 22 are guided by a guide tube 13 provided in the hopper body 1 and move in the horizontal direction. Incidentally, nine stirring plates 2 are provided on one inclined surface, each having a width of 25 mm, a thickness of 3 mm, and a pitch of 50 mm.

The drive device 3 consists of a pair of cylinder devices, each piston rod being connected to a shaft 21, 22. Driven by the drive device 3, the shafts 21 and 22 reciprocate in the same direction, and all of the stirring plates 2 simultaneously reciprocate in the horizontal direction along the inclined surfaces 11 and 12.

Using the hopper configured as described above, powdered resin was supplied to the outside by the feed screw 4 while the drive device 3 was continuously driven, and the resin could be stably supplied without bridging. By the way, the reciprocating distance of stirring plate 2 is 50
mm, and the reciprocating cycle is 12 times/min.

Although the shafts 21 and 22 are continuously driven in the same direction, they may be driven alternately or intermittently.

[Brief explanation of drawings]

FIG. 1 is a front view showing a schematic configuration of a hopper according to an embodiment of the present invention in cross section, and FIG. 2 is a side view showing the cross section of FIG. 1...Hopper body, 2...Stirring plate, 3
...Drive device, 4...Feed screw, 10
...Opening, 11, 12...Slope, 13...Guide cylinder, 21, 22...Shaft.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A hopper body shaped like a container and having a raw material supply opening opening at the lower end and an inclined surface whose cross-sectional area gradually decreases toward the opening; a plurality of stirring plates provided along the inclined surface, extending from above toward the opening, and arranged in parallel rows at intervals from each other in the horizontal direction; A hopper characterized by a drive device that reciprocates in parallel, and more. (2) The hopper according to claim 1, wherein the drive device is configured to reciprocate a plurality of stirring plates simultaneously.