JPH0387611A - Excavation level measuring instrument - Google Patents

Abstract

PURPOSE:To simply execute the continuous measurement without scarcely causing an error by displacing a differential pressure movable body in accordance with a difference of the water head of a liquid tank. CONSTITUTION:In a reference side unit 3 side, opening and closing of manual valves 19, 21 are selected, and for instance, a first pressure receiving chamber 17 of a differential pressure detector 15 is allowed to communicate with a liquid tank 8 of the measurement side through a hose 4, and on the other hand, a second pressure receiving chamber 18 is allowed to communicate with a liquid tank 14 of the reference side unit 3. Also, lazy tongs 33 are allowed to contract. In such a state, when a shield excavator 1 is brought to excavation, the hose 4 is drawn and the lazy tongs expand, and by following it, only a flexible part 4a of the hose 4 expands, and it is not drawn out of a hose reel 28. Accordingly, a pressure fluctuation which follows an expansion of the hose 4 is minute, its fluctuation does not come to bend a diaphragm 16, and the diaphragm 16 is bent exactly in response to a difference of water heads of both the tanks 8, 14 even while the hose 4 is expanding, and a level of an excavator 1 against the reference position is displayed exactly on a level display board 40.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an excavation level measuring device for measuring the excavation level of a shield excavator, a tunnel excavator, etc.

[Prior art 1] Hondaseto developed this type of measuring device Wε in Japanese Patent Application Laid-open No. 6 O-I.
We have already provided what is described in Q57Q6 publication. In this device, the measurement side liquid tank mounted separately on the excavator and the reference side liquid tank installed at the reference position are directly connected with a hose so that their liquid levels are always at the same level. The pressure at the bottom of the tank is detected separately as an electrical quantity, and the difference between the two is electrically calculated to determine the excavation level. Problem B1 to be Solved by the Invention However, in general, the distance between both liquid tanks is long, and therefore the hose that connects them becomes long. It takes a long time for the liquid to flow so that the liquid levels in both liquid tanks are the same and for the bottom pressure of each liquid tank to stabilize to a measurable state, making it impossible to continuously measure the excavation level. The measurement took a long time. In addition, the liquid level was likely to fluctuate due to swinging of the hose during excavation, often resulting in measurement errors. The present invention aims to solve these problems. [Intelligence B to be Solved by the Invention] The excavation level measuring device of the present invention is partitioned into two pressure receiving chambers by a differential pressure movable body such as a diaphragm, and converts the displacement of the differential pressure movable body into an electric quantity. A differential pressure detector having a conversion part, a measurement side liquid tank, and a reference side liquid tank, one pressure receiving chamber of the differential pressure detector is used as the measurement side liquid tank, and the other pressure receiving chamber is used as the reference side liquid tank. They are each connected. It is preferable that the measurement side liquid tank and one pressure receiving chamber of the differential pressure detector be connected via a hose, and that the middle part of the hose is bent in a meandering manner and supported by an expansion and contraction device.

[Operation] When a difference occurs in the head pressures of both the liquid tanks on the measurement side and the reference side, the differential pressure movable body of the differential pressure detector is displaced according to the pressure difference, and the amount of displacement is converted into an electrical quantity. It is taken out. That is, the difference in the head pressures of the two liquid tanks is immediately converted into a corresponding amount of electricity and detected.Since the liquids in the two liquid tanks are insulated from each other in the differential pressure detector, no liquid flow occurs. If the middle part of the hose that connects the liquid tank on the measuring side and one pressure receiving chamber of the differential pressure detector is bent in a meandering state and supported on an expansion and contraction device, the hose will be Only the meandering bent portion can be extended following the excavation without having to draw out the hose from the reel again, and therefore pressure fluctuations due to swinging of the hose can be minimized.

【Example】

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings. FIG. 1 is a system configuration diagram of an excavation level measuring device according to the present invention, which includes a measuring unit 2 mounted on, for example, a shield excavator 1, and a reference unit 3 fixed at a predetermined reference position. And these both units 2.3
a hose support unit 5 that supports the hose 4 connecting the
It is comprised of a level display unit 6 that processes electrical signals from the reference side unit 3 and displays the excavation level. As the hose 4, it is preferable to use a tube for pneumatic drive equipment piping made of nylon or polyurethane and having little deformation and low internal resistance. The measuring unit 2 has a liquid tank 8 attached to a frame or case 7, and a hose connection pipe 9 connected to the bottom of the liquid tank 8. This hose connection pipe 9 has a hose joint 10 and a manual valve 11 for drain processing.
is provided. The inside of the liquid tank 8 is exposed to the atmosphere through an atmosphere opening pipe 12 . The reference side unit 3 has a liquid tank 14 and a differential pressure detector 15 attached to a frame or case 13, and has the following piping. The inside of the differential pressure detector 15 is liquid-tightly divided into two pressure receiving chambers 17 and 18, a first and a second pressure receiving chamber, by a diaphragm 16 which is a differential pressure movable body. Pressure receiving chamber 1
7.18 are each connected to the bottom of the liquid tank 14 via a connecting pipe 20 with a manual valve 19 and to a hose connecting pipe 23 via a connecting pipe 22 with a manual valve 21. . In this way the first and second
The pressure receiving chambers 17 and 18 are both connected to the liquid tank 14 and the hose connection pipe 23, but in use, one of the two manual valves 19 is opened, the other is closed, and the two manual valves 21 are similarly connected. By opening one and closing the other, one pressure receiving chamber is communicated with the liquid tank 14 and the other pressure receiving chamber is communicated with the hose connection pipe 23. A hose joint 24 is provided at one end of the hose connection pipe 23, and a water inlet 25 is provided at the other end. In addition, a manual water injection valve 26 is provided in the middle of the hose connection pipe 23, and when used for the first time, the manual valve 26 is opened and the water injection port 25 is inserted into the reference side liquid tank 14 and the measurement side liquid tank 8. Add a measured amount of water (or other liquid). The inside of the liquid tank 14 is opened to the atmosphere through an air release pipe 27. As shown in FIGS. 2 and 3, the hose support unit 5 connects a hose reel 28 that winds up the hose 4 and a telescoping device 29 that supports the hose 4 pulled out from the hose reel 28 in a bridge-like sliding manner. It is mounted on a stand 30. The hose reel 28 is rotatably mounted between a pair of bearings 31 provided on a sliding table 30. Note that the hose reel 28 may be supported in a cantilevered manner. The expansion and contraction device 29 has a large number of links 3 as shown in FIG.
2 are sequentially crossed and the crossing portions and both ends are connected via bins, and the tongs 33 are mounted horizontally on a horizontal pedestal 34. The base end of the rage tongue 33 is a horizontal pedestal 34
The bin at the intersection of the links, excluding the base end, is slidably fitted into a guide groove 35 provided in the horizontal frame 34, and the tongs 33 can be moved back and forth while always maintaining a horizontal state. Expand and contract. The hose 4 pulled out from the hose reel 28 is bent in a direction perpendicular to the direction of expansion and contraction of the rage tongue 33 and meandered horizontally repeatedly to be lightly supported at each link intersection of the rage tongue 33. In the length portion 4a from the base end to the tip of the tongue 33, as shown in FIGS. 4 and 5, when the tongs 33 are extended and the distance between the centers of the links 33 is widened, the tongs 33 extend while reducing the meandering undulations,
Further, when the rage tongue 33 contracts, it contracts while increasing the meandering undulation. The portion 4b of the hose 4 beyond the expansion/contraction device 29 is connected at its tip to the hose joint 10 of the two measurement side units via the following truck 36 of the shield excavation a1. On the other hand, the proximal end 4c of the hose 4 pulled out to the rear of the hose reel 28 is supported halfway by the hanger 37, and the proximal end is connected to the hose joint 24 of the reference side unit 3. Now, assuming that the first pressure receiving chamber 17 is communicated with the hose connection pipe 23 and the second pressure receiving chamber 18 is communicated with the liquid tank 14, the first pressure receiving chamber 17 of the differential pressure detector 15 of the reference side unit 3 is connected. The pressure receiving chamber I7 is connected to the measuring unit 7 via the hose 4.
However, the second pressure receiving chamber 18 is blocked by a diaphragm 16. The liquid tank 14 of the reference side unit 3 is connected to this second pressure receiving chamber 18 as described above.
However, since it is isolated from the first pressure receiving chamber 17 by the manual pulp 19, the water in the liquid tank 8 side of the measurement side unit 2 and the water in the liquid tank 14 of the reference side unit 3 are in communication with each other. are separated from each other by a diaphragm 16, which deflects in response to the difference in head pressure in the two liquid tanks 8.14. The differential pressure detector 15 includes a diaphragm 16 using a piezoelectric element or the like.
It has an electrical quantity converter 38 that converts the amount of deflection into an electrical quantity. Therefore, the differential pressure detector 15 detects the head pressure of the liquid tank 8 of the measurement side unit 2 and the liquid tank 14 of the reference side unit 3.
A current signal corresponding to the difference between the water head pressure and the water head pressure (hereinafter, this difference will be referred to as a water head pressure difference) is output. This current signal is transmitted through cable 39 to a remote level display panel 40. The level display panel 40 is equipped with a distributor 41, a second delay calculator 42, a level display 43, a zero reset circuit 44, and a zero reset level display 45. A current signal corresponding to the pressure difference is converted into a DC voltage by a distributor 41, and then calculated by a -order lag calculator 42. and,
The level from the reference position of the shield excavator 1 is displayed on the level display 143. Further, when zero reset is applied by the zero reset circuit 44, the level at that time (zero reset level) is displayed on the zero reset level display 45. The data can be recorded by connecting an appropriate data logger to the data recording DC output terminal 46. The excavation level measuring device according to the present invention has the above-described configuration, and its operation and usage will be explained next. Select opening/closing of the manual valve 19.21 on the reference side unit 3 side, for example, the first pressure receiving chamber 17 of the differential pressure detector 15.
is communicated with the measurement side liquid tank 8 via the hose 4, while the second pressure receiving chamber 18 is communicated with the liquid tank 14 of the reference side unit 3. In addition, the rage tongs 33 are contracted. When the shield excavation Ial is excavated in this state, the hose 4 is pulled and the rage tongs 33 are extended as shown in FIGS. 4 and 5. In this case, only 4B extends while being supported by the rage tongue 33 and is not pulled out from the hose reel 28.
The extendable part 4a of the hose 4 is supported by the rage tongs 33 and extends without vertical vibration while maintaining the horizontal state while gradually reducing the meandering undulations. Therefore, the pressure fluctuations accompanying the extension of the hose 4 are minute, and the fluctuations do not go so far as to cause the diaphragm 16 to bend. It deflects in accurate response to the head pressure difference between the tanks 8 and 14, and the level of the shield excavator 1 relative to the reference position is accurately displayed on the level display panel 40 with little error. The water in the liquid tank 8 on the measuring side and the water in the liquid tank 14 on the reference side are insulated by the diaphragm 16 of the differential pressure detector 15.
When a difference occurs between the head pressure of the liquid tank 14 and the head pressure of the liquid tank 14,
Since it deflects in immediate response to the difference, level fluctuations of the shield excavator I are displayed moment by moment on the level display board 40 with good responsiveness and with little error, even during excavation. When the shield excavator 1 excavates one span, the telescopic portion 48 of the hose 4 extends by a predetermined length. Therefore, the reference side unit 3 that pulls out the hose 4 from the hose reel 28 by the extended length is fixed at a fixed position as described above), and the entire hose support unit 5 is required as shown in FIG. While advancing the distance, the rage tongs 33 are contracted, for example, by hand, and the pulled-out portion of the hose 4 is newly supported by the contracted rage tongs 33, and the shield excavator l is caused to dig in the same manner. In the above embodiment, the diaphragm 16 is used as the differential pressure detector 15 for detecting the head pressure difference between the liquid tanks 8 and 14.
Although a differential pressure movable body is used, a piston or the like may be used as a differential pressure movable body.

【Effect of the invention】

As described above, the excavation level measuring device of the present invention insulates the liquid in the liquid tank on the reference side and the liquid in the liquid tank on the measurement side in the differential pressure detector, and measures The excavation level is measured by displacing a differential pressure movable body such as a diaphragm and converting the amount of displacement into an amount of electricity. Therefore, as in the past, the liquid flows between both liquid tanks and waits for their liquid levels to become stable, then the liquid level height or liquid pressure of both liquid tanks is detected separately, and the difference between them is detected electrically. It has been difficult to perform continuous measurements when determining the actual value, but according to the present invention, this can be done easily and accurately with few errors, and the electrical configuration is also simplified. If the middle part of the hose that connects the pressure receiving chamber of the differential pressure detector and the measuring liquid tank is bent in a meandering manner and supported on an expansion and contraction device, the Only the meandering bent portion can be extended to follow the excavation without newly pulling out the hose from the reel, and therefore pressure fluctuations due to swinging of the hose can be minimized.

[Brief explanation of drawings]

Fig. 1 is a system configuration diagram of an excavation level measuring device as an example of the present invention, Fig. 2 is a plan view of a hose support unit therein, Fig. 3 is a side view of the same, and Figs. 4 to 6 are expansion and contraction thereof. It is an operation explanatory diagram. l...Shield excavator, 2...Measurement side unit, 3...Reference side unit, 4...
...Hose, 5...Hose support unit, 8.
...Measurement side liquid tank, 14...Reference side liquid tank, 15...Differential pressure detector, 16...
・Diaphragm, 17.18... Pressure receiving chamber.

Claims (1)

[Scope of Claims] 1. A differential pressure detector that is partitioned into two pressure receiving chambers by a differential pressure movable body such as a diaphragm and has an electrical quantity converter that converts the amount of displacement of the differential pressure movable body into an electrical quantity; a measurement side liquid tank;
1. An excavation level measuring device comprising: a reference side liquid tank; one pressure receiving chamber of a differential pressure detector is connected to the measuring side liquid tank; and the other pressure receiving chamber is connected to the reference side liquid tank. 2. The measurement side liquid tank and one pressure receiving chamber of the differential pressure detector are connected via a hose, and the middle part of the hose is bent in a meandering manner and supported on an expansion and contraction device. The excavation level measuring device according to claim 1.