JP2905728B2 - Device for determining the remaining amount of ready-mixed concrete - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ready-mixed concrete remaining amount determining apparatus for determining the remaining amount of ready-mixed concrete in a hopper of a concrete pump truck.

[0002]

2. Description of the Related Art Generally, a concrete pump truck (hereinafter simply referred to as a pump truck) is used for casting concrete. The pump truck has a hopper, and ready-mixed concrete (hereinafter simply referred to as ready-mixed concrete) is supplied to the hopper from a concrete mixer truck. The ready-mixed concrete supplied into the hopper is pressure-fed by a pump action, and is discharged toward a setting position via a discharge hose.

In the pump car, when the remaining amount of ready-mixed concrete in the hopper becomes small, the pump sucks air together with the ready-mixed concrete and pumps them. The air pumped together with the ready-mixed concrete is rapidly expanded near the pumping outlet, causing the discharge hose to undulate with great force. For this reason, not only the ready-mixed concrete is discharged omnidirectionally, but also a dangerous situation is created such that an operator arranged near the discharge hose is hit with the hose.

[0004] In order to solve such a problem, but is with the workers in Ho Tsu path to monitor the remaining amount of ready-mixed concrete, there is the worker in Herasuru direction for labor saving. Therefore, conventionally, a remaining amount determining device is provided in a pump car, and the pump is controlled based on the determination result of the remaining amount determining device. That is, the pump is stopped when the remaining amount level of the ready-mixed concrete in the hopper is determined to be less than the predetermined level, and stopped when the remaining amount level is determined to be equal to or higher than the predetermined level. The control to operate the pump in the state was performed. As the remaining amount determination device as described above, there is, for example, one having a two-point level sensor or a three-point level sensor.

In an apparatus provided with a two-point level sensor, a low level bar is disposed at a predetermined level position in a hopper. Then, when there is conduction between the low level bar and GND (ground) connected to the hopper through the ready-mixed concrete, it is determined that the remaining level of the ready-mixed concrete in the hopper is equal to or higher than a predetermined level. Also, Low
When the conduction between the level bar and GND is cut off, the remaining level is determined to be lower than the predetermined level. According to the present apparatus, since only the detection / non-detection of the Low level bar is used as the determination criterion, the level of the liquid level of the ready-mixed concrete can be promptly reflected in the determination of the remaining amount level.

[0006] In addition, an apparatus equipped with a three-point type level sensor includes a High level bar arranged at a position higher than a predetermined level in addition to the Low level bar.
Then, both the low level bar and the high level bar are GN.
It is determined that the remaining amount level is equal to or higher than the predetermined level by the presence of conduction with D. Also, both level bars and GND
If both of the continuities are interrupted, it is determined that the remaining amount level is lower than the predetermined level. According to this device, the average liquid level in the hopper can be detected by detecting the liquid level of the ready-mixed concrete at two places and two levels of the low level rod and the high level rod,
The determination of the remaining amount level is more accurate than the two-point method.

[0007]

However, the remaining amount judging device provided with the two-point level sensor judges the remaining amount of the ready-mixed concrete based on the liquid level only at the position where the Low level bar is arranged. Therefore, if the device is applied to a ready-mixed concrete having a low fluidity, it is not possible to efficiently pump the ready-mixed concrete. That is, when the ready-mixed concrete with low fluidity is sucked by the pump for pumping, the level of the sucked portion is large.
And the liquid level is difficult to level. For this reason, in the same apparatus that determines the remaining amount level based only on the local liquid level detection result, the erroneous determination that the ready-mixed concrete is equal to or less than the predetermined level despite the presence of the ready-mixed concrete in the hopper is higher than the predetermined level. However, an unnecessary pump stop operation may be performed.

[0008] Further, the remaining amount determination device provided with the three-point type level sensor does not judge that the remaining amount level is equal to or higher than the predetermined level unless both the Low level bar and the High level bar detect the level. Therefore, even in the case of ready-mixed concrete having a good fluidity that the liquid level tends to be horizontal, if the pump is stopped, the ready-mixed concrete is not supplied to the High level position which is higher than the Low level. Otherwise, the pump will not operate. Therefore, it takes time until the level of the remaining level with respect to the predetermined level is reflected on the operation of the pump in the stopped state, and it takes a while for the raw con-
When the discharge was stopped, it took a long time before the discharge was restarted.

As described above, in order to efficiently feed the ready-mixed concrete, it is necessary to select a judging means for determining the remaining amount of the ready-mixed concrete in the hopper according to the flow characteristics of the ready-mixed concrete.

The present invention has been made in view of the problems existing in the prior art described above, and an object of the present invention is to provide a device for determining the remaining amount of ready-mixed concrete in which a determination means can be selected.

[0011]

In order to achieve the above object, according to the first aspect of the present invention, it is determined whether or not the remaining level of the ready-mixed concrete contained in the container is less than a first level. Device for determining the remaining amount of ready-mixed concrete, wherein the device is disposed at a first level position in the container,
First detecting means for detecting whether or not the liquid level of the ready-mixed concrete corresponding to the disposition position is lower than a first level; and a second level being higher than the first level in the container. Based on only the first detection means and a second detection means for detecting whether or not the liquid level of the ready-mixed concrete corresponding to the arrangement position is lower than a second level; When both the first determination means and the first and second detection means for determining that the remaining level of the ready-mixed concrete in the inside is less than the first level or more than the first level, and both the first and second detection means detect less than the level, When it is determined that the remaining level of the ready-mixed concrete in the container is lower than the first level, and when both the first and second detecting means detect the level higher than the first level, the remaining level of the ready-mixed concrete in the container is determined. Quantity level is the first level A second determination means determines that at least a residual amount judging device raw concrete and a switching means for switching alternatively the first and second determination means.

According to the second aspect of the present invention, the first judging means includes a delay means, and the delay means delays the judgment by the first judging means that the level is equal to or higher than the first level by a predetermined time. is there.

According to the third aspect of the present invention, the first or the second
At least one of the detection means has a filter circuit. (Operation) According to the first aspect of the present invention, in determining whether the remaining level of the ready-mixed concrete stored in the container is lower than the first level, first, the operator switches the switching means. Is used to select the judgment means.

Here, when the first judging means is selected, the judging means judges the remaining level of the ready-mixed concrete in the container based on only the first detecting means. That is, if the liquid level of the ready-mixed concrete corresponding to the position of the first detection means is lower than the first level, it is determined that the remaining level is lower than the first level, and the liquid level is lower than the first level. If the level is equal to or higher than the level, the remaining level is determined to be equal to or higher than the first level.

[0015] When the second judging means is selected, the judging means detects that the first detecting means has detected less than the first level and the second detecting means has detected less than the second level. If so, it is determined that the remaining level of the ready-mixed concrete in the container is lower than the first level. If the first detecting means detects the first level or more and the second detecting means detects the second level or more, the remaining level of the ready-mixed concrete in the container is equal to the first level. It is determined that the level is equal to or higher than the level.

According to the second aspect of the present invention, the first detecting means detects that the liquid level is higher than the first level, and the first determining means determines that the liquid level is higher than the first level. Is delayed by a predetermined time by the delay means. Therefore, for example, if the pump is operated based on the determination result (first level or more) of the present apparatus, the operation of the pump is performed when the actual remaining level is equal to the first level, and This is performed when the amount of the product of the supply rate and the delay time increases.

[0017] In the invention of claim 3, wherein the first or RIKEN out signal by the second detection means is input to the first or second determination means via the filter circuit. Therefore, the signal input to the determination means is stabilized.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. FIG. 1 is a schematic diagram showing a concrete pump truck (hereinafter, simply referred to as a pump truck) 1,
The pump truck 1 is moved and installed at a concrete casting site to perform a casting operation. The pump truck 1 includes a hopper 2 as a container for accommodating ready-mixed concrete (hereinafter abbreviated as ready-mixed concrete) C, a pipe 4 connecting the hopper 2 and a discharge hose 3, and There is provided a pump 5 as a pressure feeding means for pressure feeding the raw concrete C in the hopper 2 toward the discharge hose 3. The pump truck 1 receives a supply of ready-mixed concrete C from a concrete mixer truck (not shown) through its hopper 2.

The pump car 1 has a remaining amount determination device 6 and a pump controller 7. The remaining amount determination device 6 determines whether the remaining amount level of the ready-mixed concrete C in the hopper 2 is lower than a predetermined level, and the pump controller 7 operates and stops the pump 5 based on the determination result.

FIG. 2 is a block diagram showing an electric configuration of the remaining amount judging device 6 and the pump controller 7. In FIG. 2, reference numeral 11 denotes first and second logical operation circuits each having three inputs and one output. 2 shows a control circuit as a determination means. The low level detection circuit 12, the high level detection circuit 13, and the switching circuit 14, which input the input values A, B, and C to the control circuit 11, respectively, include a low level rod 15, a high level rod 16, and a switching switch 1 respectively.
7 is connected. In the present embodiment, the low level detection circuit 12 and the low level bar 15 serve as the first detection means, the high level detection circuit 13 and the high level bar 16 serve as the second detection means, and the switching circuit 14 and the changeover switch 17 use the same. The switching means are respectively constituted. Also,
The pump controller 7 is connected to an output of the control circuit 11.

The low level bar 15 and the high level bar 16 are arranged in the hopper 2 respectively. L
detection height of the ow level bar 15 (L as the first level)
ow level) is a level at which the pump 5 may also draw in air when the remaining level of the ready-mixed concrete C in the hopper 2 becomes lower than that, and the detection height of the high level bar 16 (second level) High level as the level) is L
The position is slightly higher than the ow level. The GND (ground) 18 is connected to the hopper 2, and in the present apparatus 6, each of the GND 18 and the Low level bar 15 or the High level bar 16 is connected to each other by using conduction / interruption via a ready-made concrete C. The liquid level of the coexisting con C at the arrangement position is detected.

The low level detection circuit 12 is provided with a low level
The input value A is set to “1” by the conduction between the level bar 15 and the GND 18. Also, Low level stick 15 and GND 18
The input value A is set to "0" by interrupting the conduction with. The low level detection circuit 12 includes a filter circuit 12α, and sets the input value A to “1” only when a signal of a predetermined signal level or higher is detected.

The high level detection circuit 13 is provided with
Input value B due to conduction between the gh level bar 16 and GND 18
Is “1”. In addition, High level stick 16 and GND
The input value B is set to “0” by interrupting the conduction with the input signal B.
And The high level detection circuit 13 includes a filter circuit 13α, and sets the input value B to “1” only when a signal of a predetermined signal level or higher is detected.

The changeover switch 17 is used for the remaining amount determination device 6.
To function as a device with a two-point level sensor (two-point level sensor mode) or to function as a device with a three-point level sensor (three-point level sensor mode). belongs to. The switching circuit 14 sets the input value C to “1” by switching the changeover switch 17 to the two-point level sensor mode. The input value C is set to “0” by switching to the three-point level sensor mode.

A timer circuit 11α as a delay means is built in the control circuit 11, and the input value C from the switching circuit 14 is "1", that is, the remaining amount determination device 6 is in a two-point level sensor mode. Only activated if. The low-level detection circuit 1
The time from when the input value A from 2 is set to “1” to when the output value is set to “1” (described later) is a predetermined time t.
(0.5 to 2.0 sec).

The pump controller 7 includes a control circuit 1
The pump 5 is controlled on the basis of the output value from the control unit 1. That is, when the output value is “0”, the pump 5 is stopped,
When it is "1", the pump 5 is operated.

Next, the operation of the present embodiment will be described. It is assumed that the hopper 2 is empty. The operator operates the changeover switch 17 according to the flow characteristics of the ready-mixed concrete C supplied to the hopper 2 and
Mode setting. That is, the operator selects the two-point level sensor mode when the raw concrete C with high fluidity is supplied to the hopper 2, and conversely, the three-point level sensor mode when the raw concrete C with low fluidity is supplied to the hopper 2. Select the type level sensor mode. Hereinafter, the operation of each mode will be described individually. In addition, the ready-mixed concrete C having high fluidity is defined as (Low level stick 15
(Liquid level at the position of コ ン) ≒ (remaining level of ready-mixed concrete C)
It is a ready-mixed concrete that has good flow characteristics.

(Two-point level sensor mode: input value C =
[1]) As shown in the time chart of FIG. 3A, when the supply of the ready-mixed concrete C from the mixer truck to the hopper 2 is started, the ready-mixed concrete level in the hopper 2 is increased. When the liquid level of the ready-mixed concrete C at the position where the low-level bar 15 reaches the low level due to this rise, the low-level bar 15 and the GND 18 conduct, and the input value A changes from “0” to “1”. You. At the same time when the input value A becomes “1”, the timer circuit 11α is activated, and the predetermined time t
Elapses, the output value is changed from "0" to "1". Therefore, the pump 5 in the stopped state is operated, and the ready-mixed concrete C in the hopper 2 is connected via the pipe 4 and the discharge hose 3 to
It is discharged toward the casting position.

Here, when the supply of the ready-mixed concrete C to the hopper 2 is stopped and the liquid level of the ready-mixed concrete C at the position where the low-level bar 15 is disposed is lower than the low level, the conduction between the low-level bar 15 and the GND 18 is established. Is shut off. Then, the input value A is changed from “1” to “0”, and at the same time, the output value is changed from “1” to “0”. Therefore, the pump 5 in the operating state is stopped, and the pumping of the ready-mixed concrete C is stopped. In this mode, the output value is not affected by the input value B.

As described above, in the ready-mixed concrete C having a high fluidity, by selecting this mode in which only the detection / non-detection of the Low level bar 15 is used as a criterion, the level of the ready-mixed concrete level with respect to the Low level can be quickly determined. This can be reflected in the level determination, and efficient pumping of raw concrete C can be performed.

(Three-point level sensor mode: input value C =
As shown in the time chart of FIG. 3B, when the ready-mixed concrete C is supplied from the mixer truck to the hopper 2, the remaining amount level of the ready-mixed concrete C in the hopper 2 is increased.
When the liquid level of the ready-mixed concrete C at the position where the Low level bar 15 is arranged reaches the Low level due to this rise, the level becomes Low.
The w-level bar 15 and the GND 18 are conducted, and the input value A is changed from “0” to “1”. However, since the liquid level at the arrangement position of the High level bar 16 has not reached the High level, the input value B remains at "0" and the output value remains at "0".

Further, the supply of the ready-mixed concrete C is continued, and Hi
When the liquid level of the ready-mixed concrete C at the arrangement position of the high level bar 16 reaches the High level, the High level bar 1
6 and the GND 18 are conducted, and the input value B is changed from “0” to “1”. Therefore, the output value is changed from "0" to "1", and the pump 5 in the stopped state is operated. Accordingly, the ready-mixed concrete C in the hopper 2 is discharged toward the setting position via the pipe 4 and the discharge hose 3.

Here, as described in the prior art, the fresh concrete C has a low fluidity, so that the pump 5 sucks the fresh concrete C to make it difficult for the liquid level to become horizontal. Therefore,
Although depending on the balance between the amount of pumping by the pump 5 and the amount of supply to the hopper 2, the High level bar 16 repeats detection and non-detection, and the input value B becomes unstable. However, the input value A
If “ 1” is continued , the state of the output value is “1” regardless of the input value B.

Then, the supply of the ready-mixed concrete C to the hopper 2 is stopped, and the liquid level of the ready-mixed concrete C at the position where the High level bar 16 is arranged is lower than the High level, and Lo is set.
When the liquid level of the ready-mixed concrete C at the arrangement position of the w-level bar 15 becomes lower than the Low level, both the level bars 15, 16
And GND 18 are interrupted. Therefore,
The input value A and the input value B are respectively changed from “1” to “0”, and at the same time, the output value is changed from “1” to “0”. As a result, the pump 5 in the operating state is stopped, and the pumping of the ready-mixed concrete C is stopped.

As described above, in the ready-mixed concrete C having a low fluidity, by selecting this mode in which the liquid level of the ready-mixed concrete C is detected at two low-level bars 15 and high-level bars 16 and at two levels. , The average liquid level in the hopper 2 can be detected, and the determination of the remaining amount level is more accurate than the two-point type. Therefore, unnecessary stoppage of the pump 5 is not performed, and efficient pumping of the raw concrete C can be performed.

According to the embodiment having the above-described structure, the following effects can be obtained. (1 ) The two- point level sensor mode and the three-point level sensor mode can be selectively switched. If both modes are suitably selected according to the flow characteristics of the ready-mixed concrete C, an efficient Pumping becomes possible. (2) For example, in the three-point level sensor mode,
When the High level bar 16 is broken during the pressure feeding, if the mode is switched to the two-point level sensor mode, the pressure feeding can be immediately performed. Similarly, when the Low level bar 15 is damaged, remove the Low level bar 15 and set the High level bar to High.
When the mode is replaced with the level bar 16 and the mode is switched to the two-point level sensor mode, the pressure can be immediately fed. As described above, even if one of the level bars 15, 16 is damaged, it is possible to perform emergency pumping in the two-point level sensor mode by using the other level bars 16, 15 as an alternative. (3) In the two-point level sensor mode, the timer circuit 11α delays the determination that the remaining level of the raw concrete C is equal to or higher than the first level. That is, if the pump 5 is operated immediately after detecting the low level or more, the advantage of the remaining level of the ready-mixed concrete C with respect to the low level ((remaining level) − (low level)) is small, and therefore the operation of the pump 5 is performed. , The remaining level immediately becomes Low
There is a possibility that the pump 5 is stopped by interrupting the level. Therefore, although this mode is advantageous in that the level of the ready-mixed concrete level can be immediately reflected in the remaining amount determination, the excessively sensitive reaction of the pump 5 hinders a stable driving operation. Therefore, as described above, by determining that the level is equal to or higher than the first level, that is, by delaying the operation of the pump 5, an advantage of the remaining level of the raw concrete C with respect to the Low level is secured, and the pump 5 The reaction can be suppressed and a stable casting operation can be performed. (4) The low level detection circuit 12 and the high level detection circuit 13 include filter circuits 12α and 13α, respectively. Accordingly, the detection signals from the unstable level bars 15 and 1 are cut, and the input values A and B are stabilized.

The present invention can be practiced in the following modes without departing from the spirit of the present invention. (1) Instead of a sensor utilizing the conductivity of the ready-mixed concrete C, a stroke sensor utilizing the fact that the stroke amount of the detection body changes according to the liquid level of the ready-mixed concrete C may be used. (2) In the above embodiment, the pump 5 is controlled based on the determination result (output value) by the remaining amount determination device 6, but the pump 5 is changed and the operator is displayed or sounds based on the determination result. Configured to give a low level warning.

The technical ideas that can be grasped from the above embodiment will be described. (1) Pumping means 5 for pumping the ready-mixed concrete C in the container 2, the remaining amount determining device 6 according to any one of claims 1 to 3, and between the pumping means 5 and the remaining amount determining device 6. A controller 7 interposed in the container. When the remaining amount determining means 6 determines that the remaining level of the ready-mixed concrete C in the container 2 is lower than the first level, the controller 7 controls the pressure feeding means 5. A fresh concrete pumping control device that stops the pumping and activates the pumping means 5 when it is determined that the level is equal to or higher than the first level.

In this way, efficient pumping can be performed according to the flow characteristics of the ready-mixed concrete C. (2) A concrete pump truck 1 provided with the ready-mixed concrete remaining amount determination device 6 according to any one of claims 1 to 3 or the ready-mixed concrete pressure control device (6, 7) according to the above (1).

In this way, efficient pumping can be performed according to the flow characteristics of the ready-mixed concrete C.

[0041]

According to the first aspect of the present invention, the judging means can be selected. If this judging means is suitably selected in accordance with the flow characteristics of the ready-mixed concrete, for example, efficient pumping of the ready-mixed concrete can be performed. Becomes possible.

According to the second aspect of the present invention, for example, repetition of excessive operation and stop of the pump can be suppressed.
According to the third aspect of the present invention, the determination result is stabilized.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a pump car.

FIG. 2 is a block diagram showing a remaining amount determination device and a pump controller.

3A is a time chart illustrating an operation in a two-point level sensor mode, and FIG. 3B is a time chart illustrating an operation in a three-point level sensor mode.

[Explanation of symbols]

2 ... hopper as a container, 6 ... remaining amount determination device, 11 ... control circuit constituting first determination means and second determination means,
12: a low level detection circuit constituting the first detection means; 13 ... a high level detection circuit constituting the second detection means; 14: a switching circuit constituting the switching means; 15: constituting the first detection means Low level bar, 16: High level bar constituting second detection means, 17: changeover switch constituting changeover means, C: ready-mixed concrete.

Claims (3)

(57) [Claims] An apparatus for determining a remaining amount of ready-mixed concrete for determining whether a remaining level of ready-mixed concrete stored in a container is less than a first level, wherein 1 and the liquid level of the ready-mixed concrete corresponding to the position is the first level.
First detecting means for detecting whether or not the level is lower than the level of the fresh concrete, and a liquid of ready-mixed concrete arranged at a second level position higher than the first level in the container and corresponding to the arrangement position A second detecting means for detecting whether or not the surface level is less than a second level; and a residual level of the ready-mixed concrete in the container being less than the first level or based on only the first detecting means. When both the first determination means for determining that the level is equal to or higher than the first level and the first and second detection means detect a level lower than the level, the remaining level of the ready-mixed concrete in the container is set to the first level If the first and second detecting means detect that the remaining level of the ready-mixed concrete in the container is equal to or higher than the first level. Determination means; and the first and A device for determining the remaining amount of ready-mixed concrete, comprising: switching means for selectively switching the second determining means. 2. The method according to claim 1, wherein the first determining unit includes a delay unit,
2. The apparatus for determining a remaining amount of ready-mixed concrete according to claim 1, wherein the delay means delays the determination by the first determination means that the level is equal to or higher than the first level for a predetermined time. 3. The apparatus according to claim 1, wherein at least one of said first and second detecting means includes a filter circuit.
A device for determining a remaining amount of ready-mixed concrete according to item 1.