JP5707580B2 - Container position measuring device - Google Patents

Description

  The present invention relates to a container position measuring apparatus for measuring the position of a shipping container that is transported by ship, vehicle, etc. and loaded on a container yard or the like, mainly in a state of being stacked on the ground surface. .

In general, handling of shipping containers is performed by a dedicated crane. Handling of the transport container by the crane is performed by the lifting device moving means on which the lifting device is installed traversing the main body frame, and the lifting device is lifted and lowered by the lifting device lifting means. At this time, a technique for measuring the position of the transport container loaded under the crane is disclosed for the purpose of avoiding a collision between the transport container loaded under the crane and the transport container handled by the lifting device. (For example, Patent Document 1).
Hereinafter, the conventional technique for measuring the container position will be described with reference to the drawings.
FIG. 5 is an overall view of a yard crane provided with a container collision prevention device. In FIG. 5, a crane 105 that handles the container 101 is provided with a traversing body 111 that raises and lowers the hanging tool 110. A two-dimensional laser sensor 113 having a fan-shaped detection range in the transverse direction is attached to a location where the lower edge of the container 101 suspended by the hanging tool 110 can be seen on the traversing body 111. The horizontal movement direction is scanned by 113 to measure the position data of the lower edge portion of the container 101 and the corner portion of the ceiling surface of the stack target container 102.
On the other hand, the present applicant is working on the development of a method and apparatus for measuring a container position using a microwave sensor (Patent Document 2).

JP 2005-104665 A Japanese Patent Application No. 2008-270150

However, the conventional technique uses a two-dimensional laser sensor as a distance measuring sensor, but has the following problems. That is, in the two-dimensional laser sensor, the measurement medium is light, and the light is transmitted through the space at the time of measurement. At this time, the light is easily affected by atmospheric conditions (rain and fog). In some cases, measurement was impossible. The handling of shipping containers is usually done outdoors, especially when the weather conditions are bad, and it is easy to make visual mishandling, so it often relies on distance measuring sensors, which makes it impossible to measure under such conditions. The possibility of inducing a collision accident will increase.
Further, since the two-dimensional laser sensor is light, when the color of the target is black or dark, the light is absorbed and does not reflect, making measurement difficult. There are no special colors for shipping containers, so there are black and dark shipping containers. In this case, the target shipping container may not be detected, and as a result, collisions can be prevented. There was no problem. Especially when the color of the target is black, it cannot be detected at all.
Furthermore, in the prior art, it is necessary to scan the medium. Therefore, a movable part is provided in the two-dimensional laser sensor. However, it is necessary to continue swinging for scanning during sensing, and this movable part is provided. It was a complicated and expensive device. Furthermore, there was a mechanical life due to wear and adhesion of the movable part. Moreover, since the position of the ceiling edge of the target container is estimated by synthesizing the sensed data, enormous and complicated data processing is required. This makes it an expensive device.
On the other hand, when a 24 GHz FM-CW radar was installed at a certain height from the ground and the distance to the roof surface of the container was measured, it was found that stable measurement could not be performed.
That is, the wavelength of the 24 GHz radar is about 12 millimeters and its half wavelength is as short as 6 millimeters. Therefore, the received wave is affected by coherent fading due to slight unevenness of the radio wave reflection surface, and level fluctuation occurs.
Further, when the phase difference between the transmitted wave and the reflected wave is 180 degrees, the levels of the reflected wave may become zero due to cancellation.
Actually, it was assumed that the reflection level of the radio wave was not a point but a surface, so it was rare that the reflection level would be zero. When the reflection from the light source was measured, the sensitivity level varied from time to time, and sometimes the sensitivity was often lost. If the reflection level is zero or extremely low, the distance cannot be measured.
In order to prevent this, it is only necessary to rotate the radar antenna by a slight angle and scan the reflecting surface to change the position of the reflecting surface. However, if there is a moving part, it may cause a failure or mechanical wear. There is a concern that the lifetime will be shortened.

An object of the present invention is to provide a position measuring device that is not easily affected by the weather or the color of a transport container, and that can stably measure the position data of the transport container, focusing on the above-described conventional problems.
In particular, an object of the present invention is to provide a container position measuring apparatus using a microwave sensor, in which the influence of coherent fading and the reflection level do not become zero or extremely low.

The container position measuring apparatus according to the first aspect of the present invention is a container position measuring apparatus that measures the height of stacked containers using a microwave sensor that emits a microwave and receives a reflected wave of the microwave. And a trigger unit that receives a brake signal of a crane that moves on the plurality of containers, and a measurement time that determines a reception time of the measurement signal from the microwave sensor based on the brake signal at the trigger unit. A container height for calculating the container height based on the comparison of the signal level in the signal level comparison means, a signal level comparison means for comparing the signal level of the measurement signal received at the reception time; And a display means for displaying the container height determined by the container height determination means, and the measurement time The enclosed determining means, wherein the triggering means receive time a predetermined time after the brake signal is input, the reception time a predetermined time until shaking of the crane after the time of stop of the crane falls It is characterized by including as.
According to a second aspect of the present invention, in the container position measuring apparatus according to the first aspect, the plurality of microwave sensors are arranged corresponding to the plurality of rows of containers placed under the crane, The processing in the signal level comparison means, the container height determination means, and the display means is performed based on the measurement signals from the corresponding microwave sensors.
According to a third aspect of the present invention, in the container position measuring apparatus according to the second aspect, the container movement detecting means for calculating the movement position of the container by an operation signal of a lifting tool moving means for moving the container on the crane. In the movement between the columns of the containers placed under the same row in the state where the crane is stopped, the container movement position is calculated by the container movement detection means, and the container movement position is calculated by the calculated container movement position. The container height display in the display means is changed.
According to a fourth aspect of the present invention, in the container position measuring apparatus according to any one of the first to third aspects, the vehicle further includes a reset unit that receives a brake release signal of the crane or a movement signal of the crane, When the reset means receives the brake release signal or the movement signal, the trigger means receives a brake signal after reception of the signal by the reset means, the measurement time range determining means, the signal level comparing means, and the The container height is calculated by the container height determining means, and the new container height is displayed by the display means.
According to a fifth aspect of the present invention, in the container position measuring apparatus according to any one of the first to fourth aspects, the level comparison means is configured to obtain the measurement signal having a signal level smaller than a preset threshold value. It is characterized by not being compared.
According to a sixth aspect of the present invention, in the container position measuring apparatus according to any one of the first to fifth aspects, the level comparing means includes the measurement signal already received and the measurement signal newly received. And when the signal level of the new measurement signal is high, it is rewritten with the new measurement signal.

  Since the container position measuring device according to the present invention receives a measurement signal using the brake signal of the crane as a trigger signal, it can obtain a plurality of measurement signals in a state where the crane has not yet stopped, so a high signal level. The detection signal can be reliably obtained.

The front view in the installation spot of the crane which applied the container position measuring apparatus in one Example of this invention Top view of the crane on site Structure diagram of microwave sensor in the same embodiment Block diagram in the same embodiment Overall view of a yard crane equipped with a conventional container collision prevention device

The container position measuring apparatus according to the first embodiment of the present invention includes a trigger unit that receives a brake signal of a crane moving on a plurality of containers, and a measurement from a microwave sensor based on the brake signal from the trigger unit. Based on the comparison of the signal level in the measurement time range determination means for determining the reception time for receiving the signal, the signal level comparison means for comparing the signal level of the measurement signal received at the reception time, and the signal level comparison means A container height determining means for calculating the height and a display means for displaying the container height determined by the container height determining means. The measurement time range determining means has a predetermined value after the brake signal is input by the trigger means. but the time and reception time, including the reception time a predetermined time until shaking of the crane after the time of stopping the crane fit That. According to this embodiment, in order to receive a measurement signal using a crane brake signal as a trigger signal, a plurality of measurement signals can be obtained in a state where the crane has not yet stopped, and a high signal level detection signal can be obtained. Can be definitely obtained. Moreover, a measurement signal can be obtained by utilizing the swing of the crane after stopping.
The second embodiment of the present invention is a container position measuring apparatus according to the first embodiment, wherein a plurality of microwave sensors are arranged corresponding to a plurality of rows of containers placed under a crane. The signal level comparing means, the container height determining means, and the display means are performed based on the measurement signals from the corresponding microwave sensors. According to this Embodiment, the height of the container of each row | line can be measured simultaneously.
According to a third embodiment of the present invention, in the container position measuring apparatus according to the second embodiment, the container movement detecting means for calculating the movement position of the container based on the operation signal of the hanging means moving means for moving the container on the crane. In the state where the crane is stopped and the crane is stopped, the container movement position is calculated by the container movement detection means, and the container height in the display means is calculated by the calculated container movement position. The display is changed. According to the present embodiment, the height change due to the container movement between the rows when the crane is stopped can be performed with a certain height change by performing the operation signal of the lifting tool moving means.
A fourth embodiment of the present invention is a container position measuring device according to any one of the first to third embodiments, comprising reset means for receiving a crane brake release signal or a crane movement signal, When the means receives the brake release signal or the movement signal, the trigger signal receives the brake signal after receiving the signal by the reset means, and the container height is measured by the measurement time range determining means, the signal level comparing means, and the container height determining means. The height is calculated and the new container height is displayed by the display means. According to this embodiment, every time the crane moves and stops, a plurality of measurement signals in a state where the crane is not stopped are obtained in order to receive a measurement signal using the brake signal of the crane as a trigger signal. Therefore, a detection signal with a high signal level can be obtained with certainty.
The fifth embodiment of the present invention is the container position measuring apparatus according to any one of the first to fourth embodiments, wherein the signal level comparison means has a signal level smaller than a preset threshold value. Measurement signals are not subject to comparison. According to the present embodiment, it is possible to remove measurement noise and obtain an accurate signal.
The sixth embodiment of the present invention is a container position measuring apparatus according to any one of the first to fifth embodiments, in which the level comparison means and the measurement signal already received and the newly received measurement The signals are compared, and when the signal level of the new measurement signal is high, it is rewritten with the new measurement signal. According to the present embodiment, a measurement value with a high signal level can be obtained with certainty.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a front view of a crane installation site to which a container position measuring apparatus according to an embodiment of the present invention is applied, FIG. 2 is a top view of the crane installation site, and FIG. FIG. 4 is a block diagram in the same embodiment.

First, the structure of a container crane to which the present invention is applied will be described. As shown in FIG. 1, a container crane 1 (hereinafter referred to as a crane 1) is a tire mount type crane. The main body mount 11 has a gate shape, and includes a leg portion 12 and a garter portion 13 stretched on the upper portion.
A plurality of traveling wheels 15 that are rotationally driven by traveling motors 14 are mounted below the both leg portions 12.
The garter unit 13 supports a hanging tool traversing means 17 movably along the longitudinal direction of the garter section 13 (hereinafter referred to as the traversing direction). The hanging tool traversing means 17 is supported by a traversing motor (not shown). It has a structure that traverses the part 13.
The hanging tool 19 capable of holding the transport container 18 is suspended from the hanging tool traversing means 17 by the wire rope 22 and can be moved up and down by the hanging tool lifting / lowering means 28. Here, the lifting / lowering means 28 includes a winding motor and a rotating drum (not shown) provided in the lifting / lowering means 17.
An encoder (not shown) is provided on the rotating shaft of the rotating drum (not shown) so that the position of the hanger 19 in the height direction can be detected.
A driver's cab 26 is provided below the suspension traversing means 17 so that a driver operating the crane 1 can see the forward direction and directly below.
Below the garter unit 13, shipping containers 18 stacked in six rows with an upper limit of four levels are arranged in a row in the transverse direction. Here, each column is referred to as column a to column f. In addition, the shipping containers 18 are stacked in two, four, two, three, one, three stages in order from the a row to the f row. A chassis 30 that is a vehicle for transportation is arranged beside row f.
The hanging tool moving means 17 is constituted by the hanging tool traversing means 17 and the lifting tool lifting / lowering means 28.

In the longitudinal direction of the garter unit 13, a plurality of microwave sensors 31, 32, 33, 34, 35, 36, and 37 correspond to a plurality of rows (a row to f row) containers placed under the crane 1. Are arranged in a straight line.
The microwave sensors 31, 32, 33, 34, 35, 36, and 37 are fixed with a predetermined angle with respect to the traveling direction of the crane 1.
This is because when the short container is operated, the upper surface of the container is removed from directly below the microwave sensor, so that the microwave is reliably applied to the upper surface of the container with a predetermined angle and fixed. .
As shown in FIG. 2, the crane 1 moves in the row direction. In FIG. 2, the crane 1 is stopped at the position of row D, and the brake is applied in the stopped state. For example, when the transport container 18 in the B row is moved, the traveling motor 14 is driven after the brake is released to move in the B row direction. The traveling motor 14 can be controlled in speed by normal rotational speed control. When the crane 1 approaches the target B line, the traveling motor 14 decelerates and stops at the center of the B line. And stop.

Next, a specific configuration of the microwave sensors 31, 32, 33, 34, 35, 36, and 37 will be described. Note that these microwave sensors have the same structure.
In FIG. 3, an FM-CW radar module 45 is accommodated in the waterproof case 40. The antenna 43 constituting the FM-CW radar module 45 is a one-antenna type patch array antenna and is integrally coupled with the FM-CW radar module 45 and the control module 46.
Usually, the angle in which the gain is 50% with respect to the center of the emitted microwave sensor 31 is expressed as an angle, which is the directivity angle of the antenna of the microwave sensor. The angle was 4 degrees (± 2 degrees with respect to the center).
In addition, the main specifications are that the transmission frequency is 24.08-24.25 (GHz), the occupied frequency bandwidth is 76 (MHz), the transmission output power is 9 (mW), the modulation method is FM modulation CW, and the measurement time is 100 (times / second). Further, the distance measurement accuracy is suppressed to an error of ± 30 mm, and the difference can be determined for a plurality of height standard dimensions.
A terminal case 49 provided with a waterproof terminal 48 for exchanging signals and supplying power is fixed to the waterproof case 40 and fixed to a predetermined target via a stay 50 fixed so as to hold the terminal case 49. Is done.

Here, the principle of measuring the distance to the object by the FM-CW sensor used as the microwave sensor of this embodiment will be described.
The analog signal of the microwave sensor 31 output from the antenna 43 is reflected by an object to become a reception signal, and the phase difference between the transmission wave and the reception wave is detected (phase detection).
The signal output from the antenna 43 is a low-frequency signal, and a signal generally called a beat signal is obtained as follows.
Beat signal (f) = ((4 · Δf) / (ST · c)) · r (m)
Δf is the frequency sweep width, ST is the frequency sweep time, c is the speed of light, and r is the distance to the reflector.
From these relationships, it is possible to measure the distance from the object by frequency-resolving the beat signal by fast Fourier transform processing.

As described above, the FM-CW sensor is known as a sensor capable of measuring the distance. On the other hand, the FM-CW sensor using a 24 GHz microwave used in this example has the following characteristics.
1) Not affected by the medium of the propagation path.
2) Not affected by high temperature, high pressure, vacuum, dense fog, strong wind environment.
3) The distance to the target can be measured through a non-metallic window regardless of whether it is transparent or opaque.
4) The shape of the antenna can be reduced.
5) The output beam width can be easily reduced.
6) Smaller than conventional (X-band) radar.
7) An individual license is not required because technically compatible products are used.
Thus, the feature of the FM-CW sensor is suitable for measuring the position of an object outdoors.

Next, the function of the container position measuring apparatus in the present embodiment will be described with reference to FIG.
The crane 1 moving on a plurality of containers has a brake signal generating means 61 generated by a brake operation, and a brake release / driving signal generating means 62 generated by releasing the brake operation or driving instructions to the traveling motor 14. .
The lifting tool moving means 70 includes a traversing movement signal generating means 71 generated by the movement of the hanging tool traversing means 17 and a lifting / lowering movement signal generating means 72 generated by the movement of the lifting / lowering means 28.
The container position calculation unit 80 includes a trigger unit 81 that receives a brake signal from the brake signal generation unit 61, a measurement time range determination unit 82 that determines a reception time based on the brake signal from the trigger unit 81, and a measurement time. Measurement signal receiving means 83 for receiving a measurement signal from the microwave sensor 31 within the reception time determined by the range determining means 82 is provided.
The container position calculation unit 80 includes a signal level comparison unit 84 that compares the signal levels of the measurement signals received at the reception time. The signal level comparison means 84 compares the signal levels of the plurality of measurement signals received at the reception time, but compares the already received measurement signal with the newly received measurement signal, and determines the signal level of the new measurement signal. If it is higher, the measurement signal in the measurement signal storage means 85 is rewritten with a new measurement signal. Therefore, in the signal level comparison unit 84, the signal level between the measurement signal stored in the measurement signal storage unit 85 and having the highest signal level so far and the measurement signal newly received by the measurement signal reception unit 83. Compare However, the signal level comparison means 84 excludes measurement signals having a signal level lower than a preset threshold value from being compared.

When reception of the measurement signal within the reception time determined by the measurement time range determination unit 82 is completed, the container height determination unit 86 determines the container height from the signal level of the measurement signal stored in the measurement signal storage unit 85. The That is, the container height determining unit 86 calculates the container height based on the comparison of the signal level in the signal level comparing unit 84. The display means 90 displays the container height determined by the container height determination means 86.
In the measurement time range determination means 82, the predetermined time after the brake signal from the trigger means 81 is input is set as the reception time. Thus, in order to receive a measurement signal using the brake signal of the crane 1 as a trigger signal, a plurality of measurement signals can be obtained in a state where the crane 1 has not yet stopped, and a detection signal with a high signal level can be reliably obtained. Can get to.
In addition, the measurement time range determination unit 82 may include a predetermined time before the time when the brake signal is input by the trigger unit 81 as the reception time. By obtaining a measurement signal in the time zone before the trigger signal, a signal during operation can be obtained more reliably.
In addition, the measurement time range determining means 82 may include a predetermined time after the crane 1 is stopped as the reception time. By including a predetermined time after the stop of the crane 1 as the reception time, a measurement signal can be obtained using the swing of the crane 1 after the stop.
Further, the container position calculating means 80 has a container movement detecting means 87 for calculating the moving position of the container based on the operation signal of the hanging tool moving means 70.
The container movement detection means 87 receives signals from the transverse movement signal generation means 71 and the elevation movement signal generation means 72, and the movement position of the container can be calculated based on these signals.
The container movement detection means 87 calculates the movement between the columns of the containers placed in the same row when the crane 1 is stopped.
The container movement position calculated by the container movement detection means 87 changes the container position determined by the container height determination means, and changes the container height display on the display means 90. As described above, the height change by the container movement between the rows when the crane 1 is stopped can be surely performed by changing the height by the operation signal of the lifting tool moving means 70.

Further, the container position calculation means 80 has a reset means 88 that receives a brake release signal of the crane 1 or a movement signal of the crane 1. When the reset unit 88 receives the brake release signal or the movement signal, the trigger unit 81 receives the brake signal after reception of the signal by the reset unit 88, and the measurement time range determination unit 82, the signal level comparison unit 84, and the container The height determining means 86 calculates the container height, and the display means 90 displays the new container height. Thus, every time the crane 1 moves and stops, in order to receive a measurement signal using the brake signal of the crane 1 as a trigger signal, a plurality of measurement signals in a state where the crane 1 is not yet stopped are obtained. Therefore, a detection signal with a high signal level can be obtained with certainty.
Although the microwave sensor 31 has been described in the above embodiment, the microwave sensors 32, 33, 34, 35, and 36 are associated with a plurality of rows of containers placed under the crane 1. The heights of the containers in each row are measured simultaneously by separate container position calculation means 80.

As described above, according to the present invention, the measurement time range determination unit 82 uses the brake signal of the crane 1 as a trigger signal as a measurement signal by setting the predetermined time after the brake signal from the trigger unit 81 is input as the reception time. Therefore, it is possible to obtain a plurality of measurement signals in a state where the crane 1 has not stopped yet, and to reliably obtain a detection signal having a high signal level.
Further, according to the present invention, the measurement time range determining means 82 can obtain a signal during operation more reliably by including a predetermined time before the time when the trigger signal 81 is input as a brake signal as the reception time.
Further, according to the present invention, the measurement time range determination means 82 can obtain a measurement signal by using the swing of the crane 1 after the stop by including a predetermined time after the stop of the crane 1 as the reception time. .
In the present invention, a plurality of microwave sensors 31, 32, 33, 34, 35, and 36 are arranged corresponding to a plurality of rows of containers 18 placed under the crane 1, and signal level comparison means 84, containers The processing in the height determining unit 86 and the display unit 90 is performed based on the measurement signals from the corresponding microwave sensors 31, 32, 33, 34, 35, 36, thereby The height can be measured simultaneously.
Further, in the present invention, when the crane 1 is stopped, when the containers 18 placed under the same row move between the columns, the container movement detection unit 87 calculates the container movement position and displays the calculated container movement position. By changing the container height display in the means 90, a reliable height change can be performed.
Further, according to the present invention, when the reset means 88 receives the brake release signal or the movement signal, the trigger means 81 receives the brake signal again, and the measurement time range determining means 83, the signal level comparing means 84, and the container height determining means. In order to receive the measurement signal using the brake signal of the crane 1 as a trigger signal every time the crane 1 moves and stops by calculating the container height by 86 and displaying the new container height by the display means 90. In addition, it is possible to obtain a plurality of measurement signals in a state where the crane 1 has not yet stopped, and to reliably obtain a detection signal with a high signal level.
Further, according to the present invention, the signal level comparison means 84 can remove measurement noise and obtain an accurate signal by excluding a measurement signal having a signal level smaller than a preset threshold value.
Further, in the present invention, the level comparison means 84 compares the measurement signal already received with the newly received measurement signal, and rewrites with a new measurement signal when the signal level of the new measurement signal is high, A measurement value of a high signal level can be obtained with certainty.
In the present embodiment, a plurality of microwave sensors 31, 32, 33, 34, 35, 36, and 37 are placed in the longitudinal direction of the garter section 13. Since the crane 1 is arranged in a straight line corresponding to the containers in the row f), it can continuously measure the stack height of the containers in each row while moving in the row direction. Therefore, it is possible to easily grasp the row, column, and number of stacked containers in a predetermined area.
Normally, in the container yard, the positions of all containers are managed by computer in rows, columns, and stages, and container movement instructions are issued based on this position data. However, in rare cases, the crane driver may make a mistake in moving the container, and the computer-managed container position data may deviate from the actual situation. That is, a missing container is generated.
However, even in such a case, according to the present embodiment, the actual position data of the container can be obtained by grasping the row, column, and stack number of the container in an arbitrary area. The missing container can be easily found by checking the position data of the container.

  The present invention can be applied to a gantry crane and a straddle carrier used for loading and unloading a container for transportation onto a container ship, and can also be applied to a crane used for transfer to a railway vehicle.

DESCRIPTION OF SYMBOLS 1 Container crane 11 Main body mount 17 Hanging tool transverse means 18 Transport container 19 Hanging tool 31, 32, 33, 34, 35, 36 Microwave sensor 80 Container position calculation means 81 Trigger means 82 Measurement time range determination means 83 Measurement signal reception Means 84 Signal level comparison means 85 Measurement signal storage means 86 Container height determination means 87 Container movement detection means 88 Reset means

Claims (6)

A container position measuring device that measures the height of stacked containers using a microwave sensor that emits a microwave and receives a reflected wave of the microwave,
Trigger means for receiving a brake signal of a crane moving on a plurality of said containers;
Based on the brake signal at the trigger means, measurement time range determination means for determining the reception time of the measurement signal from the microwave sensor;
Signal level comparison means for comparing the signal level of the measurement signal received at the reception time;
Container height determining means for calculating the container height based on the comparison of the signal levels in the signal level comparing means;
Display means for displaying the container height determined by the container height determining means;
In the measurement time range determining means, a predetermined time after the brake signal is input by the trigger means is set as a reception time, and a predetermined time until the crane swing after the crane stops is settled. Container position measuring apparatus, comprising: as a reception time. A plurality of the microwave sensors are arranged corresponding to the plurality of rows of containers placed under the crane,
2. The container according to claim 1, wherein the processing in the signal level comparison unit, the container height determination unit, and the display unit is performed based on measurement signals from the corresponding microwave sensors. Position measuring device. A container movement detecting means for calculating a movement position of the container by an operation signal of a lifting tool moving means for moving the container on the crane;
In the inter-column movement of the containers placed under the same row in a state where the crane is stopped, the container movement detection means calculates the container movement position,
The container position measuring device according to claim 2, wherein the container height display in the display means is changed according to the calculated container movement position.   A reset means for receiving a brake release signal of the crane or a movement signal of the crane; and when the reset means receives the brake release signal or the movement signal, the trigger means after receiving the signal by the reset means The container height is calculated by the measurement time range determining means, the signal level comparing means, and the container height determining means, and the new container height is displayed by the display means. The container position measuring device according to any one of claims 1 to 3, wherein   5. The container position measuring apparatus according to claim 1, wherein the level comparison unit excludes the measurement signal having a signal level smaller than a preset threshold value.   The level comparison means compares the measurement signal already received with the newly received measurement signal, and rewrites with the new measurement signal when the signal level of the new measurement signal is high. The container position measuring device according to any one of claims 1 to 5.