JPH083382Y2 - Conveyor type powder feeder - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a device for supplying a fixed amount of powder by using a belt conveyor, and in particular, a powder having poor fluidity containing different specific gravity substances, different diameter particles, etc. The present invention relates to a powder supply device capable of supplying even a body without impairing the uniformity of mixing and suppressing a supply error.

[Conventional technology]

For quantitative supply of powder, a hopper is often used in which the outlet is finely squeezed and a closing mechanism such as a shutter is provided at that portion.However, if the hopper is powder with poor fluidity, the orifice effect and angle of repose at the outlet are used. The outflow impediment condition is likely to occur. Also,
In such a case, a method of supplementing fluidity by combining a stirring device, a vibrating device, a screw feeder, or the like is adopted, but a mixture containing fibers is particularly apt to flow out, When a powder containing a specific gravity material, particles with different diameters, etc. moves due to stirring or the like, substances having different specific gravities and particle diameters segregate and the uniformity of mixing is impaired.

On the other hand, the method of transporting the powder by a belt conveyor, dropping the powder from the conveyor into the weighing pan of the weighing machine, and stopping the conveyor when the supplied weight reaches a predetermined value is due to poor fluidity. There is no effect, and since the powder to be conveyed on the conveyor is kept in a substantially stationary state, even powders having different specific gravities and different diameters can be smoothly supplied while maintaining the uniformity of mixing.

However, if the amount of powder on the conveyor per unit movement amount of the conveyor is too large, the weighing accuracy will not be improved no matter how low the conveyor speed is, and if the amount of powder on the conveyor per unit length of the conveyor varies. After the stop command, the powder falls due to inertial rotation of the conveyor, impact at the time of stop, inertia, etc., so it is difficult to improve the weighing accuracy. Even if the stop command signal from the weighing machine is slightly accelerated in anticipation of the extra drop amount, the powder supply itself to the conveyor does not go well,
The powder conveyance width in the direction perpendicular to the traveling direction is too wide, or the width (cross-sectional area) varies in each part in the traveling direction, so that the drop amount after the stop command is not constant and the weighing accuracy deteriorates. Therefore, as shown in JP-A-62-96218, etc., the supply powder is transferred from the conveyor to another conveyor, and the amount thereof is gradually reduced by controlling the speed of each conveyor to convey the final amount It is considered to reduce the variation in the amount.

[Problems to be solved by the device]

In powder feeders that use multiple belt conveyors in combination, it is necessary to stabilize the width and height of the powder fed onto the most upstream (youngest) conveyor in order to improve the feeding accuracy between the conveyors. However, in the conventional technology, the weight of the powder in the hopper is added to the powder supplied to the conveyor from the hopper, and the supplied powder is compressed. However, the powder was agitated at this stage, the uniformity of mixing was impaired, and the powder was unevenly distributed on a part of the conveying surface, and stable supply could not be expected. For example, Japanese Utility Model Publication No. 54-37427 discloses a flow-rate stabilizing net for preventing the bridging phenomenon. However, this produces an effect close to stirring, which impairs the uniformity of mixing. Further, if the rotation speed of the net is reduced, it is difficult for the powder to spread on the entire transport surface on average.

This invention intends to solve such a problem and to enable stable quantitative supply of powder by a conveyor.

[Means for solving the problem]

One of the powder supply devices of this invention is (1) of the claim.
As described in, the at least two belt conveyors are arranged so that the powder to be conveyed is supplied from the uppermost young conveyor to the next older conveyor, and the speed of the younger conveyor is increased. A device provided with a mechanism for controlling the driving speed of each conveyor so as to be smaller than the speed of the number side conveyor, and the other one is at least two belt conveyors as described in (4) of the claim. , The youngest conveyor and the next oldest conveyor cross each other so that the powder is fed from the upper one located on the upper part to the old conveyor. The devices provided with a mechanism for controlling the driving timing or the driving speed of each conveyor so that the width of the conveyed powder on the old conveyor is smaller than the width of the conveyed powder on the conveyor are targeted for improvement. The youngest of A hopper is provided at the powder feeding point for the belt conveyor of the above, and the hopper blocks the entire outlet with a comb-shaped or mesh-shaped baffle plate having slits of a size that prevents the passage of powder due to a bridge phenomenon when stationary. The baffle plate is opened or moved at the exit blocking point to allow the powder to flow out onto the youngest belt conveyor (claim 1 or 4).

The hopper to be used is the one described in claim 2 or 5, that is, the outlet opening dimension in the direction of the youngest conveyor is larger than the inlet opening dimension, and the outlet area is larger than 1/2 of the inlet area. The outlet may be provided with a means for supporting the internal powder capable of opening the outlet.

In addition, a weight measuring mechanism is included in the old conveyor of the apparatus according to claim (1) or (2), and a weighing signal by the mechanism is incorporated in the drive control of the conveyor (claim 3), or In the device of (4) or (5), the old conveyor has a weight measuring mechanism, and the control by the above control mechanism is
The powder is supplied from the young conveyor while the old conveyor is stationary, the young conveyor is stopped when the supply weight reaches a predetermined value, and then the old conveyor is driven. It can be said that keeping (claim 6) is preferable for the reason described later.

[Action]

The equipment that sequentially transfers the powder from the youngest conveyor to the oldest conveyor is the unit length of the powder on the conveyor by making the speed of the oldest conveyor higher than the speed of the youngest conveyor. The contact weight can be freely controlled. That is, the larger the speed difference between old turn conveyor being driven at an early number conveyor and faster than this, the change value of the powder thickness is such conveyor arrangement of FIG. 2 (H-H _1), but also, the change value of the powder width (W-W ₁₎ per unit length flour weight amount of increases on old turn conveyor is reduced in such a conveyor arrangement of Figure 1.
Since the weight of powder per unit length is the convey amount per unit length of the conveyor, if it is reduced, the weighing accuracy is naturally increased when the speed of the conveyor is considered to be constant.
Therefore, the apparatus according to claim (1), (2), (4) or (5) determines the necessary weighing amount by determining the final transport amount per unit length in consideration of the conveyor speed and stopping accuracy. Alternatively, the supply accuracy can be obtained, but as described above, if the powder supply to the youngest conveyor is not stable, the effect of the above-described accuracy improvement cannot be fully utilized due to this.

In the hopper adopted in the present invention, the powder flows out from the whole area of the outlet on average, and when the baffle plate at the outlet portion is stationary by closing the outlet, or the supporting means instead of the baffle plate closes the outlet. Since the outflow of powder stops while the powder is flowing out, it is possible to prevent the weight of the powder inside the hopper from being added to the supplied powder in addition to increasing the control accuracy of the supply amount. The width and height of the powder supplied to the youngest conveyor can be stabilized by these actions, and the accuracy of the supply between the conveyors is improved and the final weighing accuracy is improved. Get even better.

It should be noted that if the convey amount per unit length by the conveyor is reduced, the time required to supply a fixed amount will be longer, but when the supply weight approaches the specified value from the weighing machine, the proximity signal is taken out until the signal is output. If the conveyor is driven at a relatively high speed and the conveyor speed is reduced by the proximity signal, the feeding time can be shortened without deteriorating the weighing accuracy.

In addition, if the configuration of (3) or (6) of the above-mentioned preferred claim is adopted, the amount of powder falling on the old conveyor can be freely set based on the weighing signal from the weight measuring mechanism. Since it can be controlled, the weighing accuracy is further improved.
Above all, the structure of claim (6) in which the old conveyor is stationary and receives the powder has a great effect of improving the weighing accuracy because stable weighing is performed.

〔Example〕

A specific example of the supply device of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the apparatus of claim (4), in which 1 is a first belt conveyor, 2 is a second belt conveyor, and 3 is a belt conveyor.
Is a weighing machine having a weighing pan 4, A is a supply powder, and 5 is a hopper for supplying the powder A onto the first belt conveyor 1.

In the apparatus shown in FIG. 1, the first belt conveyor 1 has a second
The hopper 5 is arranged above the belt conveyor 2 in a direction orthogonal to the second belt conveyor 2, and the hopper 5 is arranged at a powder supply point for the first belt conveyor 1. The powder A supplied from the hopper 5 is It is conveyed to one belt conveyor 1, supplied from the end of the conveyor 1 onto the second belt conveyor 2, and further conveyed to this conveyor 2 and dropped into the weighing pan 4 of the weighing machine 3.

This device is controlled by a control mechanism (not shown). For example, the conveyor 2 is driven at a speed higher than that of the conveyor 1 while maintaining a predetermined speed ratio, and a conveyor from a proximity signal to a predetermined weighing value from the weighing machine 3 and a stop signal. When there is a deceleration and stop of 2, the conveyor 1 is also decelerated and stopped in synchronization. The conveyor 1 is moved for a predetermined time (length) while the conveyor 2 is stationary,
Control may be performed so that the conveyor 2 moves the length of W after the stop, but in any case, since powder is supplied from the conveyor 1 to the conveyor 2 while performing such control,
The powder width W ₁ on the conveyor 2 is always smaller than the powder width W on the conveyor 1. Moreover, when the weight measuring mechanism is added to the conveyor 2, the amount of powder received by the conveyor 2 in a stationary state is controlled with high accuracy.

Further, the hopper 5 has a structure capable of stably supplying the powder containing fibers and the like onto the conveyor 1. Since the powder width W and the powder thickness H on the conveyor 1 are thereby constant, the conveyor 2 The cross-sectional area of the powder supplied to the upper part is substantially constant in each part of the conveyor 2 in the traveling direction, and variation in the amount of powder falling from the conveyor 2 is suppressed.

The hopper 5 is a baffle plate 6 having a slit having a size that prevents a powder from passing through when the bridge is stationary.
The outlet is blocked by and the baffle plate is horizontally reciprocated by the driving means 7 when required to allow the powder to flow out. Even if the powder has poor fluidity, the mixing is maintained and the powder flows out smoothly. Can be done.

The baffle plate 6 may have a comb-teeth shape as shown in FIG. 3 (the cross-sectional shape of the teeth may be non-circular) or a mesh shape not shown. Alternatively, the powder may be discharged by opening / closing the plate, rotating the plate horizontally, or the like.

Furthermore, the hopper as shown in FIG. 4 can bring about the same effect as that of FIG. In this hopper, the outlet area S is made larger than 1/2 of the inlet area S ₁ , and further, the outlet front dimension L in the traveling direction of the conveyor is made larger than the inlet front dimension L ₁ so that the powder can be opened and closed at the outlet. The body supporting means (rotary shutter in the figure) 8 is provided. This hopper prevents the weight of the powder in the upper layer from being concentrated on the powder in the lower layer, and the supporting means is elongated so that the working resistance due to the powder does not become extremely large, and a fine opening control is possible. It is possible to improve the stability and accuracy of the supply. This fourth
Combining the illustrated hopper with the conveyor of FIG. 1 results in the apparatus of claim (5).

Next, the apparatus shown in FIG. 2 will be described. The feeder shown in FIG. 2 advances two conveyors 1 and 2 directed in the same direction in the same direction or in opposite directions (the same direction in the figure), and sets the speed of the conveyor 2 located below to the speed of the conveyor 1. Faster than. Further, when the proximity signal to the predetermined weighing value is output from the weighing device 3, each of the conveyors 1 and 2 decelerates together while maintaining an optimum speed ratio, and stops when a stop signal is output. The control is, of course, based on a command from a control mechanism (not shown). In this way, the powder A does not change in width, but the thickness H is reduced to H ₁ and the weighing accuracy is improved. Also in this case, if a weight measuring mechanism is added to the conveyor 2, the dispersion of the powder weight per unit length on the conveyor 2 is corrected by the correction of the speed ratio of the conveyors 1 and 2 based on the weighing signal from the conveyor. Is desirable because it can correct

The apparatus of FIG. 2 is shown by omitting the hopper that supplies the powder onto the first conveyor 1. First on the first conveyor 1
The apparatus having the hopper 5 having the baffle plate as shown in FIGS. 3 and 4 is the apparatus of claim (1), and the apparatus having the hopper shown in FIG. 4 is the apparatus of claim (2).

[Effect of device]

As described above, in the powder supply device of the present invention, two or more conveyors are arranged in different stages so that the older conveyor has a smaller amount of powder to be conveyed per unit length. Since the powder is stably and accurately supplied from the special hopper onto the youngest conveyor, it is possible to eliminate the problem of poor supply accuracy inherent in the conveyor-type powder supply device. On the other hand, the advantage of powder feeding by the conveyor can be fully utilized, so that even powder containing fibers etc. can be quantified in a state where there is no hindrance and there are few weighing errors while maintaining the uniformity of mixing. The effect is that supply becomes possible. When the device of this invention is used for quantitative supply of raw materials for composite materials, etc.,
This is more effective because variations in the tissue distribution due to non-uniformity of mixing and variations in product density due to errors in the supply amount are prevented.

[Brief description of drawings]

1 and 2 are perspective views showing an outline of an embodiment of the device of the present invention, FIG. 3 is a partial perspective view showing a modified example of the hopper, and FIG. 4 is a further hopper. It is a perspective view. 1, 2 ... Belt conveyor, 3 ... Weighing device, 4 ... Weighing plate, 5 ... Hopper, 6 ... Baffle plate, 7 ... Driving means, 8
…… Powder supporting means, A …… Powder.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location G01G 11/12 13/08 A (56) Reference JP-A-51-98870 (JP, A) JP-A-62 -230527 (JP, A) JP 62-96218 (JP, A) JP 49-53204 (JP, A) JP 54-3766 (JP, A) Actual development JP 51-113784 (JP, U) ) Actually open 53-44883 (JP, U) Actually open 57-48426 (JP, U) JP-B 31-7209 (JP, B1) Actual 59-12929 (JP, Y2)

Claims (6)

[Scope of utility model registration request] 1. At least two belt conveyors are arranged in a state in which powder to be conveyed is supplied from a conveyor on the young side located at the top onto a conveyor on the next-order old side, and the speed of the young side conveyor is increased. In a conveyor type powder feeding device provided with a mechanism for controlling the driving speed of each conveyor so as to be smaller than the speed of the number side conveyor, a hopper is provided at the powder feeding point for the youngest belt conveyor, The hopper blocks the entire exit with a comb-shaped or mesh-shaped baffle that has slits of a size that prevents the passage of powder due to the bridge phenomenon when stationary, and either opens this baffle or moves it at the exit blocking point. A conveyor-type powder supply device characterized in that the powder is made to flow onto the youngest belt conveyor. 2. At least two belt conveyors are arranged in a state in which the powder to be conveyed is supplied from the upper conveyor on the younger side to the next older conveyor, and the speed of the younger conveyor is increased. In a conveyor type powder feeding device provided with a mechanism for controlling the driving speed of each conveyor so as to be smaller than the speed of the number side conveyor, a hopper is provided at the powder feeding point for the youngest belt conveyor, The hopper supports the inner powder that can open the outlet to the outlet by making the outlet opening size in the moving direction of the youngest conveyor larger than the inlet opening size and the outlet area larger than 1/2 of the inlet area. A conveyor-type powder supply device characterized in that means is provided. 3. The old conveyor comprises a weight measuring mechanism,
The conveyor type powder feeder according to claim 1 or 2, wherein the weighing signal by this mechanism is incorporated in the drive control of the conveyor. 4. Conveying powder is supplied onto at least two belt conveyors from a younger conveyor located at the upper part of the upper conveyor where a younger conveyor and a next older conveyor intersect each other. And a mechanism for controlling the drive timing or drive speed of each conveyor so that the width of the powder conveyed by the old conveyor is smaller than the width of the powder conveyed by the young conveyor. In a powder type powder feeder, a hopper is provided at a powder feeding point for the youngest belt conveyor, and the hopper has a comb-like shape or a slit having a size that prevents the passage of powder by a bridge phenomenon when stationary. Conveyor powder characterized in that a mesh-shaped baffle blocks the entire outlet and the baffle is opened or moved at the outlet blocking point to let the powder flow out onto the youngest belt conveyor. Supply Location. 5. Conveyance powder is supplied from at least two belt conveyors to the old conveyor by the young conveyor located at the upper position where the young conveyor and the next old conveyor intersect each other. And a mechanism for controlling the drive timing or drive speed of each conveyor so that the width of the powder conveyed by the old conveyor is smaller than the width of the powder conveyed by the young conveyor. In the powder feeding device, a hopper is provided at the powder feeding point for the youngest belt conveyor, and the hopper has a larger outlet opening size in the traveling direction of the youngest conveyor than the inlet opening size and an outlet area. Is larger than 1/2 of the inlet area, and a support means for the internal powder capable of opening the outlet is provided at the outlet part. 6. The old conveyor comprises a weight measuring mechanism,
The control by the above control mechanism supplies the powder from the young conveyor while the old conveyor is stationary, stops the young conveyor when the supply weight reaches a predetermined value, and then drives the old conveyor. (4) or (5) according to the claims
The conveyor-type powder supply device described.