JP2014091326A - Aggregate weighing device and freshly mixed concrete manufacturing apparatus with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aggregate weighing device that can weigh the aggregate efficiently and satisfactorily by solving problems in weighting accuracy, weighing time or the like.SOLUTION: An aggregate weighing device of the present invention includes: a gravel storage bin 4 for storing gravel to generate freshly mixed concrete; a weighing gate 9 for opening and closing a lower end discharge port 26 of the gravel storage bin 4; an actuator 28 for driving the opening and closing action of the weighing gate 9; a control panel 32 for controlling the actuator 28; and a weighing hopper 12 for weighing the gravel discharged from the gravel storage bin 4 by opening the weighing gate 9 with the actuator 28. The control panel 32 controls the actuator 28 to transfer the weighing gate 9 from a fully opened state to a first half-opening state, which has an opening area narrower than the opening area in this state, when a weighing value of the gravel by the weighing gate 9 gets closer to a predetermined target weighing value after fully opening the weighing gate 9.

Description

  The present invention relates to an aggregate measuring apparatus for measuring aggregate discharged from an aggregate storage bin in a raw concrete manufacturing apparatus such as a batcher plant.

  Conventionally, in ready-mixed concrete manufacturing apparatuses such as batcher plants, ready-mixed concrete is manufactured by kneading materials such as gravel as coarse aggregate, sand as fine aggregate, cement, water, and admixture ( For example, see Patent Document 1).

  When manufacturing ready-mixed concrete, the mixing ratio of each material should be set appropriately in order to improve workability when placing ready-mixed concrete and to have the desired strength after hardening of ready-mixed concrete. It is necessary to knead. For that purpose, it is important to accurately measure each material in the process of producing ready-mixed concrete.

  Of the above materials, for example, gravel will be described. In the batcher plant, gravel is stored in a gravel storage bin 40 as shown in FIG. A discharge port (not shown) is formed at the lower end of the gravel storage bin 40, and a measuring gate 41 for opening and closing the discharge port is provided at the lower part of the gravel storage bin 40. Below the gravel storage bin 40, a weighing hopper 42 for weighing the gravel is disposed.

  The weighing hopper 42 is provided with a load cell 43 as a weighing scale. In the weighing hopper 42, gravel discharged from the gravel storage bin 40 is weighed so as to have a preset target weighing value (hereinafter referred to as “target weighing value”).

  A discharge port (not shown) is formed at the lower end of the weighing hopper 42, and an opening / closing gate 44 for opening and closing the discharge port is provided below the weighing hopper 42. A mixer 45 for kneading gravel and other materials is disposed below the weighing hopper 42.

  The measuring gate 41 is supported by being suspended from the gravel storage bin 40, and is opened and closed by an actuator (cylinder) having a piston rod (not shown), for example. The measurement gate 41 is opened and closed by a command from a control panel 46 including a sequencer, for example.

  Specifically, the conventional weighing gate 41 performs the following opening / closing operation. That is, the weighing gate 41 is shifted from the fully closed state to the fully opened state when the weighing hopper 42 starts weighing. In this fully open state, a large amount of gravel is discharged from the gravel storage bin 40 to the weighing hopper 42 and is measured by the load cell 43.

  In this case, in order to perform measurement accurately, the measurement gate 41 is kept open until the measurement value by the load cell 43 reaches the target measurement value, and at the same time the measurement value reaches the target measurement value, the measurement gate 41 is turned on. A transition to the closed state is required. However, when the weighing gate 41 is fully opened and a large amount of aggregate is discharged to the weighing hopper 42, the weighing gate 41 is fully closed at such a timing that the measured value matches the target measured value. Is very difficult, and there is a problem that the measurement error is large even when the measurement gate 41 is fully closed.

  Therefore, in the conventional weighing method, coarse weighing is performed once, and then fine weighing is performed. That is, when the measured value approaches the target measured value, the weighing gate 41 is temporarily closed from the fully open state to temporarily stop discharging gravel. Thereafter, as a fine measurement, the measurement gate 41 is controlled to perform a so-called jogging operation in which a fully open state and a fully closed state are alternately repeated a plurality of times.

  In this jogging operation, gravel discharge is reduced as compared with the fully opened state at the start of measurement, so that the measurement error can be further reduced. Further, there is an advantage that the impact applied to the weighing hopper 42 can be reduced during the jogging operation.

  However, in this jogging operation, the gravel discharge amount when the opening and closing operation of the measuring gate 41 is performed only once is almost constant, and therefore it is impossible to measure with less accuracy than this fixed amount. Therefore, there is a problem in terms of weighing accuracy. Further, in the jogging operation, since the operation of closing and opening the measurement gate 41 is repeated, there is a problem that it takes time for the measurement.

  Further, in the jogging operation, since the measurement gate 41 is repeatedly opened and closed, there is a disadvantage that the measurement gate 41 is severely worn by an impact caused by gravel and the like, and the deterioration rate of the measurement gate 41 is increased. Further, in the jogging operation, when the measuring gate 41 is fully closed, the flow of gravel temporarily stops. Therefore, the gravel is in a consolidated state at the inner bottom portion of the gravel storage bottle 40, and in the next fully opened state. There is also a problem that gravel is difficult to discharge.

JP-A-8-183021

  The present invention has been conceived under the circumstances described above, and is an aggregate measuring apparatus that can efficiently and satisfactorily measure aggregates by solving problems in measuring accuracy, measuring time, and the like. The issue is to provide Moreover, let it be the subject to provide the ready-mixed concrete manufacturing apparatus provided with the aggregate measuring apparatus.

  The aggregate metering device provided by the first aspect of the present invention is a storage means for storing aggregate as a material for producing ready-mixed concrete, an opening / closing means for opening and closing a lower end discharge port of the storage means, A driving means for driving the opening / closing operation of the opening / closing means, a control means for controlling the driving means, and a storage means are provided below the storage means, and the opening / closing means is opened by the driving means and discharged from the storage means. Measuring means for measuring the aggregate, wherein the control means sets the opening and closing means to a fully open state, and then sets the aggregate measurement value by the measuring means in advance. When the target measured value is approached, the precursor driving means is controlled to shift the opening / closing means from the fully open state to a first half-open state having an opening area smaller than the opening area in this state. It is characterized in.

  In the aggregate measuring apparatus according to the present invention, the aggregate measuring device includes first detection means for detecting a stop position of the opening / closing means in the first half-open state, and the control means is based on an output of the first detection means. By controlling the driving means, the opening / closing operation of the opening / closing means may be stopped to shift to the first half-open state.

  In the aggregate metering device of the present invention, the opening / closing means comprises an opening / closing gate provided at the lower end of the storage means so as to be freely opened / closed, and the driving means comprises a hollow main body formed in an elongated shape, Preferably, the first detection means is a detection switch that is attached to a predetermined position of the main body and detects the movement position of the piston rod.

  In the aggregate metering device of the present invention, it is preferable that the detection switch can be adjusted in its mounting position on the main body.

  In the aggregate metering device of the present invention, the control means assumes that the amount of the aggregate discharged from the storage means is desired after the open / close means is shifted from the fully open state to the first half open state. When the amount deviates, the driving means may be controlled to shift the opening / closing means from the first half-open state to a second half-open state having an opening area different from the opening area in this state.

  The aggregate metering device of the present invention further comprises second detection means for detecting a stop position of the opening / closing means in the second half-open state, and the control means is based on the output of the second detection means. By controlling the driving means, the opening / closing operation of the opening / closing means may be stopped to shift to the second half-open state.

  In the aggregate metering device of the present invention, the opening area in the second half-open state may be set to be slightly wider than the opening area in the first half-open state.

  In the aggregate metering device of the present invention, the opening in the first half-open state and the second half-open state is rectangular in plan view, and the ratio of the vertical length and the horizontal length of the opening is , 1: 0.15 to 1: 0.3 is preferable.

  The ready-mixed concrete manufacturing apparatus provided by the second aspect of the present invention includes the aggregate metering apparatus provided by the first aspect of the present invention.

  According to the present invention, after the opening / closing means (for example, the measurement gate) is fully opened, when the aggregate measurement value by the measurement means approaches the target measurement value, the measurement gate is changed from the fully open state to the narrow opening area. 1 to the half-open state. Therefore, since the aggregate discharged in a large amount in the fully opened state can be discharged little by little in the first half-opened state, the opening / closing means can be opened and closed as in the conventional jogging operation. Compared to the case of repeating, weighing can be performed with high accuracy. Moreover, since the fully open state and the fully closed state are not repeated, the measurement time can be shortened. Therefore, it is possible to provide an aggregate measuring device capable of efficiently and satisfactorily measuring aggregates.

It is a figure which shows the schematic structural example of the batcher plant as a ready-mixed concrete manufacturing apparatus with which the aggregate measuring apparatus which concerns on 1st Embodiment of this invention is applied. It is a block diagram of a measurement gate and an actuator, and is a figure which shows the fully closed state of a measurement gate. It is a figure which shows the fully open state of a measurement gate, (a) is a block diagram of a measurement gate and an actuator, (b) is a figure which shows the magnitude | size of the discharge port of a gravel storage bin. It is a figure which shows the half open state of a measurement gate, (a) is a block diagram of a measurement gate and an actuator, (b) is a figure which shows the magnitude | size of the discharge port of a gravel storage bin. It is a block diagram of the measurement gate and actuator which concern on 2nd Embodiment of this invention, and is a figure which shows the fully closed state of a measurement gate. It is a figure which shows the fully open state of a measurement gate, (a) is a block diagram of a measurement gate and an actuator, (b) is a figure which shows the magnitude | size of the discharge port of a gravel storage bin. It is a figure which shows the 1st half-open state of a measurement gate, (a) is a block diagram of a measurement gate and an actuator, (b) is a figure which shows the magnitude | size of the discharge port of a gravel storage bin. It is a figure which shows the 2nd half open state of a measurement gate, (a) is a block diagram of a measurement gate and an actuator, (b) is a figure which shows the magnitude | size of the discharge port of a gravel storage bin. It is a figure which shows the 3rd half open state of a measurement gate, (a) is a block diagram of a measurement gate and an actuator, (b) is a figure which shows the magnitude | size of the discharge port of a gravel storage bin. It is a schematic block diagram which shows the conventional aggregate measuring device.

  Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.

<First Embodiment>
FIG. 1 is a diagram illustrating a schematic configuration example of a batcher plant as a ready-mixed concrete manufacturing apparatus to which an aggregate measuring device according to a first embodiment of the present invention is applied.

  This batcher plant 1 is an apparatus for producing ready-mixed concrete, and is manufactured by kneading gravel (coarse aggregate), sand (fine aggregate), cement, water, admixture, etc., which are constituent materials of ready-mixed concrete. To do. The batcher plant 1 has storage bins and storage tanks according to the plurality of materials. Specifically, as shown in FIG. 1, the batcher plant 1 includes a cement storage bin 2 for storing cement, a sand storage bin 3 for storing sand, a gravel storage bin 4 for storing gravel, and a water storage for storing water. It has a tank 5 and an admixture storage tank 6 for storing the admixture.

  At the lower ends of the cement storage bin 2, the sand storage bin 3, and the gravel storage bin 4, measuring gates 7, 8, and 9 are provided for discharging the respective materials downward. Details of the measurement gate will be described later.

  Under each storage bin 2, 3 and 4, weighing hoppers 10, 11 and 12 are provided for weighing the material discharged from them. Each weighing hopper 10, 11, 12 is provided with load cells 13, 14, 15 as weighing scales for weighing materials in the weighing hoppers 10, 11, 12 respectively.

  The cement, sand, and gravel stored in the storage bins 2, 3, and 4 are discharged to the weighing hoppers 10, 11, and 12 when the weighing gates 7, 8, and 9 are opened. In each weighing hopper 10, 11, 12, the discharged cement, sand and gravel are weighed by the load cells 13, 14, 15, respectively. If the measured value by each load cell 13,14,15 becomes a target measured value, the measurement gates 7, 8, and 9 will be in a closed state, respectively.

  Opening gates 16, 17, 18 for discharging the respective materials downward are provided at the lower ends of the weighing hoppers 10, 11, 12, respectively, below each of the weighing hoppers 10, 11, 12. A raw material chute 19 for collecting the discharged raw materials is provided.

  On the other hand, a water metering hopper 21 is connected to the water storage tank 5 via a flow rate adjustment valve 20, and the water stored in the water storage tank 5 is adjusted in the outflow by the flow rate adjustment valve 20, and the water metering is performed. A predetermined amount of water is temporarily stored in the hopper 21. An admixture metering hopper 23 is connected to the admixture storage tank 6 via a flow meter 22 and a pump (not shown). The admixture stored in the admixture storage tank 6 is stored in the flowmeter 22 or the like. The pump is allowed to flow out, and a predetermined amount of the admixture is temporarily stored in the admixture metering hopper 23.

  A mixer 24 is provided on the downstream side of the raw material chute 19, the water metering hopper 21, and the admixture metering hopper 23 to knead the materials discharged from them. That is, when cement, gravel and sand are fed into the mixer 24 from the raw material chute 19, a predetermined amount of water discharged from the water metering hopper 21 and a predetermined amount of admixture discharged from the admixture metering hopper 23. Is mixed.

  The aggregate measuring device according to the present embodiment is applied respectively to the measurement of gravel as a coarse aggregate and the measurement of sand as a fine aggregate. Hereinafter, for the convenience of explanation, an aggregate measuring device for measuring gravel will be described, but the aggregate measuring device for measuring sand is also configured in the same manner.

  As shown in FIG. 2, a substantially rectangular discharge port 26 is formed at the lower end of the gravel storage bin 4 in plan view, and the discharge port 26 is an opening extending in the depth direction in FIG. 2. .

  As shown in FIG. 2, the measuring gate 9 is supported in a freely suspended manner with a predetermined position below the gravel storage bin 4 as a fulcrum so as to open and close the discharge port 26 of the gravel storage bin 4. That is, the measuring gate 9 is rotated by an actuator (cylinder) 28 supported by a support member 27 extending in the lateral direction of the gravel storage bin 4 to open and close the discharge port 26.

  The actuator 28 is formed in a long shape, and a base end of the actuator 28 is rotatably supported by a support member 27. The actuator 28 slides in the actuator body 29 and can move forward and backward with respect to the actuator body 29. And a piston rod 30 provided on the front side. The tip of the piston rod 30 is rotatably supported by the lower part of the measuring gate 9. A proximity switch 31 is attached to a predetermined position on the peripheral side surface of the actuator body 29.

  As shown in FIG. 2, when the piston rod 30 is in the most advanced state from the actuator body 29, the measuring gate 9 is in a state where the discharge port 26 of the gravel storage bin 4 is most closed (hereinafter referred to as “fully closed state”). maintain. 3A, when the piston rod 30 is in the most retracted state in the actuator main body 29, the discharge port 26 is in the most open state (hereinafter referred to as “full open state”). ). Further, as shown in FIG. 4A, the measuring gate 9 is in a state where the discharge port 26 is opened halfway (hereinafter referred to as “half-open state”) when the piston rod 30 is advanced halfway through the actuator body 29. ).

  The proximity switch 31 detects the moving position of the piston rod 30 in the actuator body 29. That is, a magnet (not shown) for detection is fitted in the vicinity of the base end of the piston rod 30, and the base end of the piston rod 30 that slides within the actuator body 29 determines the mounting position of the proximity switch 31. When passing, the proximity switch 31 outputs a detection signal to the control panel 32 described later. The control panel 32 stops the piston rod 30 based on this detection signal. The member to be detected of the proximity switch 31 is not limited to the magnet.

  When the piston rod 30 stops in the actuator body 29, the opening / closing operation of the measuring gate 9 also stops. The measurement gate 9 is stopped at a position where the measurement gate 9 is in a half-open state. That is, the proximity switch 31 is used for detecting the moving position of the piston rod 30 and for the control unit 32 to detect the stop position of the measuring gate 9, that is, the half-open state of the measuring gate 9.

  Accordingly, the stop position of the measuring gate 9 is defined by the installation position of the proximity switch 31 on the peripheral side surface of the actuator body 29, that is, the opening area of the measuring gate 9 in the half-open state is defined.

  The opening area in the half-open state of the measuring gate 9 is when the ratio of the length in the depth direction (vertical direction) to the width direction (lateral direction) is in the range of 1: 0.15 to 1: 0.3. As will be described later, it is clear from experiments by the applicant that it is optimal for discharging a small amount of gravel. Hereinafter, the ratio of the length in the depth direction to the length in the width direction is referred to as “vertical / horizontal ratio”.

In the present embodiment, when the measuring gate 9 is in a fully open state, the opening is an area S ₀ with an aspect ratio of 1: 0.6, as shown in FIG. 3B, and the measuring gate 9 is in a half-open state. At this time, as shown in FIG. 4B, the area S ₁ has an aspect ratio of 1: 0.2.

  Note that the aspect ratio when the measuring gate 9 is in the half-open state is not limited to the above-described numerical values. For example, the aspect ratio is 1: 0 which is approximately the center value of the optimum range of 1: 0.15 to 1: 0.3. A value such as .225 may be used.

  The proximity switch 31 is, for example, screwed to the peripheral side surface of the actuator body 29 via a predetermined mounting member, and its mounting position can be adjusted along the longitudinal direction of the actuator body 29. Therefore, since the proximity switch 31 is used to detect the half-open state of the measuring gate 9 as described above, the opening area in the half-open state can be changed by adjusting the mounting position.

  In the present embodiment, the proximity switch 31 is used to detect the half-open state of the measuring gate 9, but the present invention is not limited to this. For example, an external switch provided on the measuring gate 9 side may be used.

  A control panel 32 is connected to the load cell 15, the actuator 28, and the proximity switch 31 (see FIG. 1). The control panel 32 includes, for example, a sequencer, and comprehensively controls each component device of the batcher plant 1. In this embodiment, the control panel 32 is based on a measured value from the load cell 15, a detection signal from the proximity switch 31, and the like. Thus, an operation signal for opening and closing the measuring gate 9 is output to the actuator 28.

  In this embodiment, a small amount of gravel falls from when the operation signal for closing the weighing gates 7, 8, 9 is output until the weighing gates 7, 8, 9 are actually closed. The target measurement value described above is a value that takes into account the weight of gravel or the like for the fall.

  The aggregate metering device according to the present embodiment includes a gravel storage bin 4, a metering gate 9, an actuator 28, a metering hopper 12 including a load cell 15, a proximity switch 31, and a control panel 32 for controlling them. In this case, the gravel storage bin 4 functions as “storage means” described in the claims, the weighing gate 9 functions as “opening / closing means” described in the claims, and the weighing hopper 12 includes the claims. The actuator 28 functions as the “driving means” described in the claims, the control unit 32 functions as the “control means” described in the claims, and The proximity switch 31 functions as “first detection means” described in the claims.

  Next, the operation of the aggregate measuring device according to the first embodiment will be described.

  When the gravel measurement is started in the production process of ready-mixed concrete, the control panel 32 controls the actuator 28 so that the measuring gate 9 changes from the fully closed state (see FIG. 2) to the fully open state (see FIG. 3A). Make it work. In other words, the actuator 28 is operated so that the piston rod 30 protrudes from the actuator body 29 to the retracted state in the actuator body 29.

  The proximity switch 31 detects the magnet in the vicinity of the base end during the retraction movement of the piston rod 30, but the control panel 32 is in the process of changing from the fully closed state at the start of measurement to the fully open state. The detection signal from the proximity switch 31 is ignored.

When the measuring gate 9 is fully opened, the opening becomes an area S ₀ that is widened to the maximum with an aspect ratio of 1: 0.6 (see FIG. 3B). Therefore, a large amount of gravel is discharged from the gravel storage bin 4 (see arrow A in FIG. 3A), and weighing is performed in the weighing hopper 12.

  When it is determined by the output signal from the load cell 15 that the measurement value in the weighing hopper 12 has approached the target measurement value, the control panel 32 shifts the measurement gate 9 from the fully open state to the half open state (see FIG. 4A). That is, when the measurement value approaches the target measurement value, the control panel 32 moves the piston rod 30 from the retracted state into the actuator body 29 in the protruding direction. If the proximity switch 31 detects the magnet (not shown) of the piston rod 30 during this movement, the control panel 32 stops the piston rod 30. As a result, the measuring gate 9 is stopped in the half-open state shown in FIG.

Therefore, as shown in FIG. 4B, the opening in the half-open state is narrowed to an area S ₁ where the ratio is 1: 0.2. Therefore, a large amount of gravel is discharged from the gravel storage bin 4 in the fully-open state. From the state that has been done, a small amount of gravel is discharged in the half-open state (see arrow B in FIG. 4A).

  Next, when the control panel 32 determines that the measurement value in the weighing hopper 12 has reached the target measurement value based on the output signal from the load cell 15, the control panel 32 shifts the measurement gate 9 to the initial fully closed state (see FIG. 2). That is, the control panel 32 moves the piston rod 30 so as to protrude from the actuator body 29. By the operation of the actuator 28, the measuring gate 9 is fully closed, the gravel is not discharged from the gravel storage bin 4, and the measurement is finished.

Thus, according to this embodiment, the metering gate 9 is fully opened and gravel large amount was drained, when approaching the metering target value, and a metering gate 9 in the half-open state with a very small opening area S _1, Gravel is discharged little by little. That is, gravel emissions are reduced step by step during weighing. When the measurement target value is reached, the measurement gate 9 is fully closed, and the gravel discharge is stopped.

  In the conventional weighing method, when the weighing target value is approached, the weighing gate 41 is temporarily closed and the jogging operation is repeated to repeatedly open and close the weighing gate 41. Gravel discharge when the weighing gate 41 is opened and closed only once is performed. Since the amount was almost constant, it could not be measured with less accuracy than this fixed amount.

  However, according to the present embodiment, the measuring gate 9 is temporarily opened halfway during the measurement, the opening area of the discharge port 26 is narrowed, the gravel is discharged little by little, and the state of being discharged little by little is fully closed. The gravel can be accurately measured.

  Further, in this embodiment, the jogging operation that repeatedly opens and closes the weighing gate 9 is not performed, and the weighing gate 9 is half-opened during weighing. Therefore, the weighing gate 9 is not closed during weighing, and gravel is always discharged. Is done. That is, since the flow of gravel is not stopped, the measurement time can be shortened. Moreover, when discharging gravel, it is possible to suppress as much as possible that gravel collides with the measuring gate 9 to generate noise and that gravel is scattered.

  In addition, since the number of opening / closing operations of the weighing gate 9 can be greatly reduced as compared with the conventional jogging operation, the number of times the impact is generated in the measuring gate 9 when gravel is discharged can be greatly reduced. Therefore, it is possible to prevent the weighing gate 9 from being severely worn, and it is possible to improve the durability of the weighing gate 9 and the actuator 28 that drives its opening and closing.

  Furthermore, since the proximity switch 31 is screwed, its mounting position can be easily adjusted, so that the aspect ratio of the opening through which gravel is discharged can be freely adjusted within the optimum range. Therefore, for example, even if the type of gravel to be weighed or the particle size of the aggregate is changed, the installation position of the proximity switch 31 corresponding to the gravel can be changed to a position where the optimum opening area is obtained. Thereby, for example, there is no need to use a measuring gate having a different shape depending on the type of gravel and the like, and only one proximity switch 31 is required, so that the cost of parts can be reduced.

Second Embodiment
FIG. 5 is a configuration diagram of the measuring gate 9 and the actuator 28 according to the second embodiment, and is a diagram showing a fully closed state of the measuring gate 9. In the second embodiment, a plurality of proximity switches are provided, and the control panel 32 adjusts the opening area of the weighing gate 9 in the half-open state based on the outputs of the plurality of proximity switches. And different. The second embodiment is characterized in that the area of the opening through which gravel is discharged is finely adjusted by providing a plurality of proximity switches. About another structure, it is substantially the same as the structure of 1st Embodiment.

  In the aggregate metering device of the second embodiment, as shown in FIG. 5, first to third proximity switches 33, 34, and 35 are attached to the peripheral side surface of the actuator body 29.

The first proximity switch 33 is disposed at a substantially central position on the peripheral side surface of the actuator body 29. The first proximity switch 33 is used to detect the half-open state of the measuring gate 9 as in the proximity switch 31 of the first embodiment. The opening in the half-open state has an area S ₁ (see FIG. 7B) in which the aspect ratio is 1: 0.2 (hereinafter, in the second embodiment, the half-open state is referred to as “first "Half-open state").

The second proximity switch 34 is disposed in the center of the actuator body 29 and slightly closer to the proximal end of the actuator body 29 than the installation position of the first proximity switch 33. The second proximity switch 34 is used to detect a half-open state that is slightly wider than the opening in the first half-open state (hereinafter, this half-open state is referred to as a “second half-open state”). The opening in the second half-open state has an area S ₂ (see FIG. 8B) having an aspect ratio of 1: 0.3.

The third proximity switch 35 is disposed in the center of the actuator body 29 and slightly closer to the tip of the actuator body 29 than the installation position of the first proximity switch 33. The third proximity switch 35 is used to detect a half-open state that is slightly narrower than the opening in the first half-open state (hereinafter, this half-open state is referred to as a “third half-open state”). The opening in the third half-open state has an area S ₃ (see FIG. 9B) having an aspect ratio of 1: 0.015.

  The control unit 32 controls the operation of the piston rod 30 based on the detection signals of the first to third proximity switches 33 to 35 so that the measuring gate 9 is in the first to third half-open states.

  Next, the operation of the aggregate measuring device according to the second embodiment will be described.

  When the gravel measurement is started in the production process of ready-mixed concrete, the control panel 32 controls the actuator 28 so that the measuring gate 9 changes from the fully closed state (see FIG. 5) to the fully open state (see FIG. 6A). Make it work. In the fully open state, a large amount of gravel is discharged from the gravel storage bin 4 (see arrow C in FIG. 6A), and the weighing hopper 12 performs weighing.

  When the control panel 32 determines that the measurement value has approached the target measurement value based on the output signal from the load cell 15, the control panel 32 shifts the measurement gate 9 from the fully open state to the first half-open state (see FIG. 7A). The aspect ratio of the opening in the first half-open state is, for example, 1: 0.2. Thereby, the quantity of gravel discharged | emitted from the gravel storage bin 4 becomes small compared with a fully open state (refer arrow D of Fig.7 (a)).

  At this time, gravel may clog the opening due to the properties of gravel or the particle size of gravel, or the amount of discharged gravel may be extremely reduced. In such a case, the control unit 32 determines that the gravel discharge amount deviates from a desired assumed amount based on the output signal from the load cell 15, and sets the weighing gate 9 from the first half-open state to a second slightly larger than that. To a half-open state (see FIG. 8A). The aspect ratio of the opening in the second half-open state is, for example, 1: 0.3. It should be noted that the determination of whether or not the gravel discharge amount deviates from the desired assumed amount may be performed not only based on the output signal from the load cell 15 but also taking into account the measurement time, for example.

  As described above, since the opening area of the discharge port 26 is slightly widened as compared with the first half-open state, gravel clogged in the discharge port 26 is discharged from the gravel storage bin 4 (see FIG. 8A). As shown in the arrow E), smooth gravel can be discharged.

  When the control unit 32 determines that the gravel has been smoothly discharged by the output signal from the load cell 15, the third half-open state in which the weighing gate 9 is slightly narrower than the second half-open state (see FIG. 9A). To migrate. The aspect ratio of the opening in the third half-open state is, for example, 1: 0.15. At this time, since the gravel clogged in the second half-open state is removed, the gravel is discharged well (see arrow F in FIG. 9A). In this case, the second half-open state may be shifted to the first half-open state again.

  When the control panel 32 detects from the output signal from the load cell 15 that the measured value in the weighing hopper 12 has reached the target measured value, it shifts the weighing gate 9 to the initial fully closed state (see FIG. 5). Thereby, discharge of gravel from the gravel storage bin 4 is prevented, and the weighing is finished.

  Thus, according to the aggregate measuring apparatus according to the second embodiment, when gravel discharge is hindered due to the properties of gravel, the measuring gate 9 is moved from the first half-open state to the second wider than that. Transition to the half-open state. That is, by adjusting the opening of the measuring gate 9 from the first half-open state, the opening and closing state of the measuring gate 9 is automatically adjusted even when gravel discharge is hindered due to the properties of the gravel. Gravel can be discharged efficiently and smoothly.

  Various patterns can be applied as the adjustment operation pattern in the half-open state of the measuring gate 9. In the above-described embodiment, the half-open state of the measuring gate 9 is adjusted in the order of the first half-open state → the second half-open state → the third half-open state → the fully-closed state. When it is determined that the gravel discharge is good when the state is changed, for example, the third half-open state may be omitted, and the order of the first half-open state → the second half-open state → the fully closed state may be used.

  Further, when it is determined that the opening in the first half-open state is too wide and the gravel discharge amount is large as in the full-open state when the first half-open state is shifted from the full-open state, the second half-open state is changed. You may abbreviate | omit and may make it transfer to the 3rd half-open state with the least discharge | emission amount.

  Alternatively, the state may be shifted from the fully opened state to the second half-opened state with the largest amount of discharge, and then the half-opened state may be adjusted appropriately according to the amount of gravel discharged. Then, the half-open state may be appropriately adjusted according to the amount of gravel discharged. Note that the adjustment operation pattern of the weighing gate 9 in the half-open state is not limited to the above-described pattern.

  In addition, as a method of making the measuring gate 9 into the half-open state, the base end sides of the two actuators are connected to each other, the two actuators are configured in a straight line, the two actuators are extended in the fully-open state, A method of extending only one of the actuators is conceivable.

  However, in this method, since the stroke of the extending actuator is constant, the opening area of the measuring gate 9 in the half-open state is also constant. For this reason, the half-open state cannot be finely adjusted as in the second embodiment, and two actuators are required to make the half-open state. In the embodiment, such inconvenience can be solved.

  The scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, the form, size, quantity, structure, and the like of the gravel weighing bin, the weighing gate, the actuator, the weighing hopper, the proximity switch, and the control unit in the above embodiment are not limited to the above embodiment, and can be appropriately changed in design. . In the above embodiment, the numerical value in the aspect ratio of the opening in the half-open state is not limited to the numerical value shown in the above-described embodiment.

  In the above embodiment, an actuator (cylinder) is used as a mechanism for opening and closing the weighing gate 9. However, the mechanism is not limited to this as long as the mechanism can open and close the weighing gate 9. Further, in the above embodiment, the load cell 15 determines whether the measured value in the weighing hopper 12 is close to the target measured value or that gravel discharge is hindered due to the property of gravel or the particle size of gravel. However, the present invention is not limited to this. For example, it may be determined by detecting the outflow of gravel using a surveillance camera or infrared light.

  Moreover, in the said embodiment, it was set as the structure which measures cement, gravel, and sand with a separate measurement hopper, but it is not limited to this structure, and cement, gravel, and sand are measured with one measurement hopper. Alternatively, gravel and sand may be measured with a single weighing hopper.

DESCRIPTION OF SYMBOLS 1 Batcher plant 2 Cement storage bin 3 Gravel storage bin 4 Sand storage bin 7, 8, 9 Weighing gates 10, 11, 12 Weighing hoppers 13, 14, 15 Load cells 16, 17, 18 Open / close gate 24 Mixer 26 Discharge port 28 Actuator 29 Actuator body 30 Piston rod 31 Proximity switch 32 Control panel 33 First proximity switch 34 Second proximity switch 35 Third proximity switch

Claims (9)

A storage means for storing aggregate as a material for producing ready-mixed concrete;
Opening and closing means for opening and closing a lower end discharge port of the storage means;
Driving means for driving the opening and closing operation of the opening and closing means;
Control means for controlling the drive means;
A measuring means provided below the storing means, and measuring means for measuring the aggregate discharged from the storing means when the opening / closing means is opened by the driving means,
The control means includes
After the opening and closing means is fully opened, when the aggregate measurement value by the measurement means approaches a predetermined target measurement value,
The aggregate metering device is characterized in that the precursor driving means is controlled to shift the opening / closing means from the fully open state to a first half-open state having an opening area smaller than the opening area in this state. Comprising first detection means for detecting a stop position of the opening / closing means in the first half-open state;
The control means includes
The aggregate measuring apparatus according to claim 1, wherein the driving means is controlled based on the output of the first detection means to stop the opening / closing operation of the opening / closing means and shift to the first half-open state. . The opening / closing means comprises an opening / closing gate provided at the lower end of the storage means so as to be freely opened and closed,
The driving means is composed of an actuator having a hollow main body formed in an elongated shape and a piston rod that can move forward and backward in the main body,
The aggregate measuring apparatus according to claim 2, wherein the first detection means is a detection switch that is attached to a predetermined position of the main body and detects a movement position of the piston rod. The detection switch is
The aggregate measuring apparatus according to claim 3, wherein an attachment position in the main body is adjustable. The control means includes
After shifting the opening / closing means from the fully open state to the first half-open state, when the aggregate discharge amount from the storage means deviates from a desired assumed amount,
The bone according to any one of claims 1 to 4, wherein the driving means is controlled to shift the opening / closing means from the first half-open state to a second half-open state having an opening area different from the opening area in this state. Material weighing device. A second detection means for detecting a stop position of the opening / closing means in the second half-open state;
The control means includes
The aggregate measuring device according to claim 5, wherein the driving means is controlled based on the output of the second detection means to stop the opening / closing operation of the opening / closing means and shift to the second half-open state. . The opening area in the second half-open state is
The aggregate metering device according to claim 5 or 6, wherein the aggregate metering device is set to be slightly wider than an opening area in the first half-open state. The openings in the first half-open state and the second half-open state are rectangular in plan view,
The aggregate according to any one of claims 5 to 7, wherein a ratio of a longitudinal length and a lateral length of the opening is set within a range of 1: 0.15 to 1: 0.3. Weighing device.   A ready-mixed concrete manufacturing apparatus comprising the aggregate measuring apparatus according to claim 1.

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