JP2015038440A - Filling sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filling sensor capable of reliably detecting not only a state of being completely filled with a fluid but also a state of a level of the fluid having approached.SOLUTION: A filling sensor 1 for detecting a filling state of grout 51 comprises a first LED 5 and a second LED 7, and a first phototransistor 6 and a second phototransistor 8 for respectively detecting a light beam emitted from the first LED 5 and the second LED 7 and reflected by the grout 51. The filling sensor further comprises a transparent plate 9 with which the first phototransistor 6 and the first LED 5 are covered. The filling state of the grout 51 is determined by using a detection signal of the first phototransistor 6 covered with the transparent plate 9 and a detection signal of the second phototransistor 8 not covered with the transparent plate 9.

Description

  The present invention relates to a filling sensor that detects that a fluid such as grout or concrete is filled in an object to be filled.

  Conventionally, in a prestressed construction method, it is known that a tubular sheath as a filling object is embedded in a precast member to form a through hole, a PC cable is inserted, and a grout as a fluid is filled and integrated. ing. If there is an unfilled space inadequately filled with the grout, the PC cable may come into contact with air and rust or the like may occur. Therefore, a detection sensor is mounted on the sheath to detect whether the grout is filled.

  For example, the filling sensor disclosed in Patent Document 1 uses a pair of electrodes to detect that moisture-containing concrete or grout contacts the electrodes. Further, an optical liquid level sensor as in Patent Document 2 is also known.

JP 2007-9681 A JP-A-9-178534

  However, in the filling sensor of Patent Document 1, it is detected that the fluid containing water contacts the pair of electrodes and the voltage between the electrodes becomes a value close to 0 V to detect the contact of the fluid. However, it is inconvenient because it cannot detect whether the fluid has approached.

  Then, although use of an optical liquid level sensor like patent document 2 can be considered, since this liquid level sensor passes light in the liquid, it detects the fluid which does not have optical transparency like grout. There is a problem that can not be.

  Therefore, a sensor that uses the light emitting element and the light receiving element to detect that the light from the light emitting element is reflected by the fluid with the light receiving element is conceivable. With this sensor, when the fluid is not approaching, the light from the light emitting element is not received by the light receiving element, but when the fluid is approaching, the light from the light emitting element is received by the light receiving element, It can detect approaching. However, when the sensor and the fluid are completely in contact with each other, there is no space for light reflection, and the light receiving element does not receive the light from the light emitting element, so that it cannot be distinguished from the state where the fluid is not close to the sensor.

  The present invention has been made in view of the above points, and the object of the present invention is to ensure not only the state where the fluid is completely filled in the filling sensor but also the state where the fluid level of the fluid is approaching. The goal is to make it detectable.

  In order to achieve the above object, in the present invention, at least two light receiving elements are used, and a fluid filling state is detected using a plurality of detection signals.

Specifically, in the first invention, on the premise of a filling sensor for detecting a filling state of a fluid,
The filling sensor is
A sensor substrate;
At least one light emitting element provided on the sensor substrate;
At least two light receiving elements that are provided on the sensor substrate and detect that the light from the light emitting elements is reflected by the fluid; and
Of the at least two light receiving elements, covers at least one light receiving element and the light emitting element, and maintains a distance for delivering light reflected by the fluid to the light receiving element when the fluid contacts the transparent plate. With a transparent plate,
The fluid filling state can be determined using a detection signal of the light receiving element covered by the transparent plate and a detection signal of the light receiving element not covered by the transparent plate.

  According to said structure, when the fluid is not approaching, the light emitted from any light emitting element is not received by any light receiving element. When the fluid approaches, the light emitted from the light emitting elements is reflected and received by the respective light receiving elements, and it is detected that the fluid has approached. Furthermore, when the fluid comes into contact with the light receiving element that is filled with the fluid and is not covered with the transparent plate, the light receiving element has no space to reflect the light that has been received from the light emitting element so far, and receives no light. The light emitting element covered with the transparent plate can receive light emitted from the light emitting element covered with the transparent plate, even if the fluid contacts the transparent plate. For this reason, it is possible to reliably detect the filled state until the fluid comes into contact with the filling sensor.

The second invention also presupposes a filling sensor that detects the filling state of the fluid,
The filling sensor is
A sensor substrate;
At least one light emitting element provided on the sensor substrate;
At least two light receiving elements that are provided on the sensor substrate and detect that the light from the light emitting elements is reflected by the fluid; and
Of the at least two light receiving elements, covers at least one light receiving element and the light emitting element, and maintains a distance for delivering light reflected by the fluid to the light receiving element when the fluid contacts the transparent plate. A transparent plate,
A light-shielding plate that blocks passage of light between at least one of the light-receiving elements and all of the light-emitting elements when the fluid comes into contact with the transparent plate;
The filling state of the fluid can be determined using a detection signal of the light receiving element on the light emitting element side and a detection signal of the light receiving element separated by the light shielding plate.

  According to said structure, when the fluid is not approaching, the light emitted from any light emitting element is not received by any light receiving element. When the fluid approaches, the light emitted from the light emitting elements is reflected and received by the respective light receiving elements, and it is detected that the fluid has approached. When the fluid is further filled and the fluid comes into contact with the transparent plate, the light receiving element that is shielded from light by the light shielding plate does not receive the light previously received from the light emitting element, while the light emitting element that is not shielded by the light shielding plate Can receive the light emitted by the light emitting element covered with the transparent plate even when the fluid contacts the transparent plate. For this reason, it is possible to detect both the state in which the fluid is filled until it contacts the filling sensor and the state in which the fluid is approaching.

  As described above, according to the present invention, the detection signal of the light receiving element covered by the transparent plate and the detection signal of the light receiving element not covered by the transparent plate are used, or the detection signal of the light receiving element on the light emitting element side. And the detection signal of the light receiving element separated by the light shielding plate, it is possible to reliably detect not only the state where the fluid is completely filled in the filling sensor but also the state where the fluid level of the fluid is approaching.

It is sectional drawing which expands and shows the outline | summary of a filling sensor and its periphery, (a) shows the state which grout approached, (b) shows the state which grout contacted. It is sectional drawing which shows a mode that grout is filled into the sheath with which the filling sensor was attached. It is a top view which expands and shows a filling sensor. It is a graph which shows the relationship between the change of the distance from the grout surface, and the voltage detected by the 1st phototransistor or the 2nd phototransistor. It is a figure equivalent to FIG. 1 which concerns on the modification 1 of Embodiment 1, (a) shows the state which the grout approached, (b) shows the state which the grout contacted. FIGS. 1A and 1B are diagrams corresponding to FIG. 1 according to the second modified example of the first embodiment, in which FIG. 1A shows a state where the grout is approaching, FIG. The state which contacted the 2nd photo reflector side is shown. FIG. 5 is a diagram corresponding to FIG. 4 according to a second modification of the first embodiment. It is a figure equivalent to FIG. 1 which concerns on Embodiment 2, (a) shows the state which the grout approached, (b) shows the state which the grout contacted. FIG. 9 is a diagram corresponding to FIG. 7 according to a second modification of the first embodiment. It is a figure equivalent to FIG. 1 which concerns on the modification 1 of Embodiment 2, (a) shows the state which the grout approached, (b) shows the state which the grout contacted. It is a figure equivalent to FIG. 1 which concerns on the modification 2 of Embodiment 2, (a) shows the state which the grout approached, (b) shows the state which the grout contacted.

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

(Embodiment 1)
FIG. 2 shows a cross section of the sheath 50 to which the filling sensor 1 according to the first embodiment of the present invention is attached. As shown in FIG. 3 in an enlarged manner, the filling sensor 1 includes a sensor substrate 2 made of a rectangular plate-like printed circuit board or the like. Are bonded and electrically connected. The first photoreflector 3 is provided with a first LED 5 as one light emitting element and a first phototransistor 6 as one light receiving element. The first phototransistor 6 serves to detect that the light from the first LED 5 is reflected by the grout 51 as a fluid. Similarly, the second photo reflector 4 is provided with a second LED 7 as one light emitting element and a second phototransistor 8 as one light receiving element. The second phototransistor 8 plays a role of detecting that the light from the second LED 7 is reflected by the grout 51 as a fluid.

  The first photoreflector 3 is covered with a transparent plate 9 made of, for example, a polyvinyl chloride plate, which is transparent on the surface side of the first LED 5 and the first phototransistor 6. On the other hand, the second photo reflector 4 is not covered with the transparent plate 9. That is, as shown in FIG. 1, when viewed from below, the second photo reflector 4 is exposed on the surface side, and the first photo reflector 3 is hidden behind the transparent plate 9. Note that the first phototransistor 6 and the second phototransistor 8 are broadly hatched for easy viewing.

  The filling sensor 1 includes a cable 10 including an output line extending from the first phototransistor 6 and the second phototransistor 8, and the cable 10 is connected to a power source, an adjustment resistor, and a voltmeter (not shown). ing. For example, the voltmeter can display a change in voltage and can record the change.

  Next, the operation of the filling sensor 1 according to this embodiment will be described.

  As shown in FIG. 2, when the grout 51 is almost not filled in the sheath 50 or when it is not filled at all, the light emitted from the first LED 5 and the second LED 7 is not reflected within a predetermined distance. , Neither the first phototransistor 6 nor the second phototransistor 8 receives light. For this reason, in FIG. 4, a voltage becomes near zero.

  As shown in FIG. 1A, when the filling rate of the grout 51 is increased and the grout 51 approaches the filling sensor 1, the light emitted from the first LED 5 is reflected on the surface of the grout 51 and is reflected by the first phototransistor 6. Light received from the second LED 7 is reflected by the surface of the grout 51 and received by the second phototransistor 8. Thereby, it is detected that the grout 51 is approaching. As shown in FIG. 4, as the grout 51 approaches, the amount of light picked up by the first phototransistor 6 and the second phototransistor 8 increases and the voltage gradually increases. In particular, since the second phototransistor 8 side not covered with the transparent plate 9 is close to the grout 51, the maximum voltage is obtained when the distance x to the grout 51 is about 1 mm. If the distance x to the grout 51 is smaller than 1 mm, the distance from the second LED 7 becomes too close to receive the light from the second LED 7, and the voltage from the second phototransistor 8 decreases. On the other hand, the voltage increases on the first phototransistor 6 side.

  Further, as shown in FIG. 1B, when the grout 51 is sufficiently filled and the grout 51 comes into contact with the second phototransistor 8 not covered with the transparent plate 9, the grout 51 reflects the light from the second LED 7. The space disappears, and the second phototransistor 8 does not receive any light received from the second LED 7 until then. On the other hand, the first LED 5 covered with the transparent plate 9 can pass light by the thickness of the transparent plate 9 even when the grout 51 contacts the transparent plate 9. The light emitted by can be received. As shown in FIG. 4, when the distance x to the grout 51 becomes 0, the voltage on the first phototransistor 6 side becomes maximum, and the second phototransistor 8 side becomes 0. In this way, by comparing the voltages of both, it is possible to detect the state in which the grout 51 is filled until it contacts the filling sensor 1.

  Thus, the filling state of the grout 51 is determined by using the detection signal of the first phototransistor 6 covered with the transparent plate 9 and the detection signal of the second phototransistor 8 not covered with the transparent plate 9. be able to.

  Therefore, according to the filling sensor 1 according to the present embodiment, not only the state in which the grout 51 is completely filled in the filling sensor 1 but also the state in which the liquid level of the grout 51 approaches can be reliably detected.

  Although not shown, even if the first photoreflector 3 and the second photoreflector 4 are separated from each other, each has a light emitting element, so that the filling state of the grout 51 can be reliably detected.

-Modification 1 of Embodiment 1-
FIG. 5 shows a filling sensor 1 ′ according to a first modification of the first embodiment of the present invention, which differs from the first embodiment in that the number of light emitting elements is different. In the following modified examples and Embodiment 2, the same parts as those in FIGS. 1 to 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the present modification, the second photo reflector 4 ′ does not have the second LED 7, but has only the second phototransistor 8. The second phototransistor 8 is provided at a position where the light from the first LED 5 can be received. Also in this modification, an output voltage similar to that in FIG. 4 can be obtained.

  In this case, the first LED 5 and the second phototransistor 8 need to be at a short distance, but there is an advantage that the second LED 7 can be omitted.

-Modification 2 of Embodiment 1
FIG. 6 shows a filling sensor 1 ″ according to a second modification of the first embodiment of the present invention, which is different from the first embodiment in that the transparent plate 9 protrudes.

  In this modification, the first photo reflector 3 and the second photo reflector 4 are bonded to the sensor substrate 2 at the same height. For this reason, the transparent plate 9 covering the first photo reflector 3 is configured to protrude.

  In this case, as shown in FIG. 7, an output voltage different from that in FIG. 4 is obtained. That is, when the grout 51 is hardly filled in the sheath 50 or not filled at all, the light emitted from the first LED 5 and the second LED 7 is transmitted to both the first phototransistor 6 and the second phototransistor 8. Since no light is received, the voltage is near zero.

  As shown in FIG. 6A, when the filling rate of the grout 51 is increased and the grout 51 approaches the filling sensor 1, the light emitted from the first LED 5 is reflected on the surface of the grout 51 and is reflected by the first phototransistor 6. Light received from the second LED 7 is reflected by the surface of the grout 51 and received by the second phototransistor 8. Thereby, it is detected that the grout 51 is approaching. As shown in FIG. 7, the voltage gradually increases as the grout 51 approaches.

  As shown in FIG. 6B, when the distance x with the grout 51 is about 1 mm, the grout 51 comes into contact with the transparent plate 9 to obtain the maximum voltage. When the distance x to the grout 51 is smaller than 1 mm, the light from the second LED 7 cannot be received gradually, and the voltage from the second phototransistor 8 becomes smaller. On the other hand, the first phototransistor 6 side is kept at the maximum voltage because the grout 51 is not further approached by the transparent plate 9.

  Further, as shown in FIG. 6C, when the grout 51 is sufficiently filled and the grout 51 comes into contact with the second phototransistor 8 not covered with the transparent plate 9 (x = 0), the light from the second LED 7 is emitted. , And the second phototransistor 8 does not receive any light previously received from the second LED 7. On the other hand, since the first LED 5 covered with the transparent plate 9 can pass light through the transparent plate 9 as usual, the light emitted from the first LED 5 similarly covered with the transparent plate 9 can be received. As shown in FIG. 7, when the distance x to the grout 51 becomes 0, the voltage on the first phototransistor 6 side becomes the maximum, and the second phototransistor 8 side becomes 0. In this way, by comparing the voltages of both, it is possible to detect the state in which the grout 51 is filled until it contacts the filling sensor 1.

  Also in this modification, the filling state of the grout 51 is determined by using the detection signal of the first phototransistor 6 covered by the transparent plate 9 and the detection signal of the second phototransistor 8 not covered by the transparent plate 9. can do.

(Embodiment 2)
FIG. 8 shows a filling sensor 101 according to the second embodiment of the present invention, which differs from the first embodiment in that the transparent plate 109 has a shape and a light shielding plate 111.

  That is, in the present embodiment, the first photo reflector 3 and the second photo reflector 4 are bonded to the sensor substrate 2 at the same height as in the second modification of the first embodiment. The transparent plate 109 of the present modification covers both the surfaces of the first photo reflector 3 and the second photo reflector 4. However, the first photoreflector 3 and the second photoreflector 4 are disposed at a predetermined distance so that the second phototransistor 8 does not receive the reflected light of the light of the first LED 5.

  On the transparent plate 109, a light shielding plate 111 is provided between the second LED 7 and the second phototransistor 8. The light shielding plate 111 may be formed of two colors of resin containing black ink when the transparent plate 109 is molded, or a separately molded light shielding plate 111 may be attached. The light shielding plate 111 serves to block the passage of light between the second phototransistor 8 and the second LED 7 when the grout 51 contacts the transparent plate 109.

  Although not shown, the first photoreflector 3 and the second photoreflector 4 are adjacent to each other, and a light shielding plate 111 is provided at the boundary between them so that the light from the first LED 5 does not reach the second phototransistor 8. Good.

  In this embodiment, as shown in FIG. 9, an output voltage similar to FIG. 7 is obtained. That is, when the grout 51 is hardly filled in the sheath 50 or not filled at all, the light emitted from the first LED 5 and the second LED 7 is transmitted to both the first phototransistor 6 and the second phototransistor 8. Since no light is received, the voltage is near zero.

  As shown in FIG. 8A, when the filling rate of the grout 51 increases and the grout 51 approaches the filling sensor 1, the light emitted from the first LED 5 is reflected on the surface of the grout 51 and is reflected by the first phototransistor 6. While being received, the light emitted from the second LED 7 is reflected by the surface of the grout 51 and received by the second phototransistor 8 without being influenced by the light shielding plate 111. Thereby, it is detected that the grout 51 is approaching. As shown in FIG. 9, the voltage gradually increases as the grout 51 approaches.

  As shown in FIG. 8B, when the distance x to the grout 51 is about 1 mm, the maximum voltage is obtained. In the present embodiment, since both the first phototransistor 6 and the second phototransistor 8 are covered with the transparent plate 109, the distance x to the grout 51 does not become smaller than 1 mm. When the grout 51 comes into contact with the transparent plate 109, even if the light from the second LED 7 is reflected by the grout 51, the light blocking plate 111 does not go to the second phototransistor 8 side. For this reason, the electric power of the second phototransistor 8 is kept at 0V, and the first phototransistor 6 is kept at the maximum voltage. Thereby, it can be determined that the filling is completed. This makes it possible to detect a state in which the grout 51 is filled until it comes into contact with the transparent plate 109 of the filling sensor 101.

  Also in this embodiment, since the detection signal of the first phototransistor 6 on the first LED 5 side and the detection signal of the second phototransistor 8 separated by the light shielding plate 111 are used, only in a state where the grout 51 is completely filled. In addition, the state in which the liquid level of the grout 51 approaches can be reliably detected.

-Modification 1 of Embodiment 2
FIG. 10 shows a filling sensor 101 ′ according to the first modification of the second embodiment of the present invention, which differs from the second embodiment in that the number of light emitting elements is different.

  In the present modification, the second photo reflector 4 ′ does not have the second LED 7, but has only the second phototransistor 8. The second phototransistor 8 is provided at a position where the light from the first LED 5 can be received. Also in this modification, an output voltage similar to that in FIG. 9 can be obtained.

  In this case, the first LED 5 and the second phototransistor 8 may be at a short distance, and the second LED 7 can be omitted, which has the advantage of reducing the size of the filling sensor 101 '.

-Modification 2 of Embodiment 2
FIG. 11 shows a filling sensor 101 ″ according to a second modification of the second embodiment of the present invention, which is different from the first embodiment in that it includes a light shielding plate 111 ″.

  In this modification, the first photoreflector 3 and the second photoreflector 4 are bonded to the sensor substrate 2 at the same height, the first photoreflector 3 is covered by the transparent plate 9, and the light shielding plate 111 '' is provided. The second photo reflector 4 side is covered. A plurality of through holes 111a '' are formed in the light shielding plate 111 ''.

  In this case, when the grout 51 is hardly filled in the sheath 50 or not filled at all, the light emitted from the first LED 5 and the second LED 7 is emitted from the first phototransistor 6 and the second phototransistor 8. Since neither is received, the voltage is near zero.

  As shown in FIG. 11A, when the filling rate of the grout 51 is increased and the grout 51 approaches the filling sensor 1, the light emitted from the first LED 5 is reflected on the surface of the grout 51 and is reflected by the first phototransistor 6. While being received, the light emitted from the second LED 7 is reflected by the surface of the grout 51 through the through-hole 111a ″, and is again received by the second phototransistor 8 through the through-hole 111a ″. Thereby, it is detected that the grout 51 is approaching. As shown in FIG. 9, the voltage of the first phototransistor 6 gradually increases as the grout 51 approaches.

  As shown in FIG. 11B, when the grout 51 is sufficiently filled and the grout 51 comes into contact with the light shielding plate 111 ″, the light from the second LED 7 is not reflected through the through hole 111a ″, and the second The phototransistor 8 does not receive any light that has been received from the second LED 7 through the through hole 111a ″ until then. On the other hand, since the first LED 5 covered with the transparent plate 9 can pass light through the transparent plate 9 as usual, the light emitted from the first LED 5 similarly covered with the transparent plate 9 can be received. For this reason, the voltage is maximum on the first phototransistor 6 side, and 0 on the second phototransistor 8 side. Thus, it is possible to detect a state in which the grout 51 is filled until it contacts the filling sensor 1.

  Also in this modification, the filling state of the grout 51 is obtained by using the detection signal of the first phototransistor 6 covered with the transparent plate 9 and the detection signal of the second phototransistor 8 covered with the light shielding plate 111 ″. Can be determined.

(Other embodiments)
The present invention may be configured as follows for each of the above embodiments.

  That is, in each of the above embodiments, the fluid is grout 51. However, the fluid is not limited to this, and may be fresh concrete having low translucency as long as it has fluidity. Further, the filling detection target is not limited to the grout filling the sheath 50, and may be a fluid such as concrete filled in the mold due to construction, civil engineering or the like. In particular, in a cylindrical frame method for embedding a hollow cylindrical frame in a bridge slab for weight reduction, a hollow slab method for embedding a lightweight embedding material such as a polystyrene foam in a building floor member, etc. If the filling sensor of the present invention is attached to the lower part of the cylindrical formwork or lightweight embedding material, the inner surface of the formwork, etc., the reinforcing bars arranged in this formwork, the aforementioned cylindrical formwork, the narrow gap of the embedding material, It is possible to confirm whether the fluid is filled in places that are difficult to see, such as the cylindrical form and the back surface of the embedding material.

  In each of the above embodiments, the transparent plate 9 is a polyvinyl chloride plate, but may be an acrylic plate, a glass plate, or the like, and may have a cavity inside.

  In each of the above embodiments, the number of the first LED 5 and the second LED 7 and the number of the first phototransistor 6 and the second phototransistor 8 is minimized, but a plurality of them may be provided.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or a use.

  As described above, the present invention is useful for a filling sensor that detects that a fluid having low translucency such as grout is filled in an object to be filled.

1, 1 ′, 1 ″ Filling sensor 2 Sensor substrate 3 First photo reflector 4, 4 ′ Second photo reflector 5 First LED (light emitting element)
6 First phototransistor (light receiving element)
7 Second LED (light emitting device)
8 Second phototransistor (light receiving element)
9 Transparent plate 10 Cable 50 Sheath 51 Grout (fluid)
101, 101 ′, 101 ″ Filling sensor 109 Transparent plate 111, 111 ″ Shading plate 111a ″ Through hole

Claims (2)

In the filling sensor for detecting the filling state of the fluid,
A sensor substrate;
At least one light emitting element provided on the sensor substrate;
At least two light receiving elements that are provided on the sensor substrate and detect that the light from the light emitting elements is reflected by the fluid; and
Of the at least two light receiving elements, covers at least one light receiving element and the light emitting element, and maintains a distance for delivering light reflected by the fluid to the light receiving element when the fluid contacts the transparent plate. With a transparent plate,
The fluid filling state can be determined using a detection signal of the light receiving element covered by the transparent plate and a detection signal of the light receiving element not covered by the transparent plate. Filling sensor to do. In the filling sensor for detecting the filling state of the fluid,
A sensor substrate;
At least one light emitting element provided on the sensor substrate;
At least two light receiving elements that are provided on the sensor substrate and detect that the light from the light emitting elements is reflected by the fluid; and
Of the at least two light receiving elements, covers at least one light receiving element and the light emitting element, and maintains a distance for delivering light reflected by the fluid to the light receiving element when the fluid contacts the transparent plate. A transparent plate,
A light-shielding plate that blocks passage of light between at least one of the light-receiving elements and all of the light-emitting elements when the fluid comes into contact with the transparent plate;
The filling is characterized in that the filling state of the fluid can be determined using a detection signal of the light receiving element on the light emitting element side and a detection signal of the light receiving element separated by the light shielding plate. Sensor.

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