JP2000221072A - Screw type sounding level meter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent detachment of a member and to continuously measure. SOLUTION: This screw type sounding level meter has a motor 3 vertically provided in a ceiling part of a tower tank, a screw 6 provided to a rotating shaft of the motor 3, extending downward; a weight body 8 screwing on the screw 6, a rotation preventing means 14 for preventing rotation of the weight body 8 together with the screw 6, a rotation angle measuring means 16 for measuring a rotation angle of the screw 6; a driving torque detection means 18 for detecting an increasing change in a driving torque of the motor 3 caused by contact of the weight body 8 descending according to the rotation of the screw 6 with an upper end face of stored reserve, and a level calculating machine 19 for calculating a level of the weight body 8 according to the rotation angle of the screw 6 when receiving a detection signal from the driving torque detection means 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sounding level meter for measuring a level of an upper end face of a stored product in a tower tank in order to measure a stored amount of the stored product.

[0002]

2. Description of the Related Art In general, in order to measure the amount of stored powdery storage material in a tower tank, the level of the upper end surface of a predetermined position of the storage material is measured by a sounding level meter. .

Conventionally, a tape-type sounding level meter 51 as shown in FIG. 4 has been used.

In the sounding level meter 51, a tape drum 53 around which a metal tape 52 is wound is rotated by a motor 54, and the tape 52 is fed downward. A weight body 55 is attached to the leading end of the tape 52, and the weight body 55 descends in the tower tank with the feeding of the tape 52.

When the weight body 55 reaches the upper end surface of the storage, the apparent weight is reduced, the tension of the tape 52 is reduced, and the tape 52 is slackened. Proximity switch 5
6, the motor 54 is stopped, and the tape 52
The scale formed on the surface is read.

[0006]

However, in the above sounding level meter 51, a metal tape 52 is required.
Has been repeated many times, so that the tape 52 is broken, and the weight 55 may fall into the storage in the tower tank.

When the weight body 55 falls into the storage, it is difficult to find it, and even if it is found, it is very difficult to take it out.

Further, in the tape type sounding level meter 51, after one measurement is completed, the next measurement cannot be performed unless the tape 52 is completely wound up, so that continuous measurement can be performed. Did not.

Therefore, the present invention has been devised to solve the above-mentioned problem, and an object of the present invention is to measure the level continuously without a member such as a weight body dropping into a storage. It is to provide a sounding level meter that can be performed.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is a sounding level meter for measuring the level of the upper end surface of a stored product in a tower tank. A motor provided in the ceiling portion of the tower tank in the vertical direction, a screw screw provided extending downward on the rotation axis of the motor, a weight body screwed to the screw screw, and the weight body is Anti-rotation means for preventing rotation together with the screw, rotation angle measuring means for measuring the rotation angle of the screw, and the weight body is moved down by the rotation of the screw to be stored on the upper end surface of the stored object. A drive torque detecting means for detecting a change in the drive torque of the motor that increases upon contact, and receiving a detection signal from the drive torque detection means, the rotation angle of the screw and the position of the weight at that position It is obtained by a level calculator for calculating the bell.

According to the above construction, since the weight body is screwed to the screw screw, it is securely supported, and the screw screw has high strength and can be broken like a conventional metal tape. Because there is no weight, the weight will not fall off. In addition, since the level of the weight is calculated from the angle of rotation of the screw, after one measurement is completed, the weight can be raised slightly to prepare for the next measurement. Level measurement.

The rotation preventing means is provided in parallel with the screw and the upper end thereof is fixed to a fixed system such as a motor support, and the rod is formed in the weight and penetrates the rod. Those formed with through holes are preferred.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a side view showing an embodiment of a screw type sounding level meter according to the present invention, FIG. 2 is a side view showing an attached state of the screw type sounding level meter, and FIG. 3 is a screw type sounding level meter. 5 is a flowchart showing an operation state of the first embodiment.

First, the configuration of the screw type sounding level meter according to the present invention will be described.

As shown in FIG. 1 and FIG. 2, in a tower tank such as a silo 2, a powdery storage material 23 such as cement is carried in from a belt conveyor 22 provided at an upper portion thereof, and is stored in a lower payout port (see FIG. 1). (Not shown) to discharge the stock 23.

The screw type sounding level meter 1 is provided to measure the storage amount of the storage material 23 in the silo 2.

This screw type sounding level meter 1
Is provided with a motor 3 provided in a vertical direction on a ceiling portion of a tower tank such as a silo 2. The motor 3 is fixed to a support 5 spanned over an opening 4 formed in a ceiling portion, and is provided so that a rotating shaft (not shown) faces downward.

A screw 6 extending downward is provided on the rotating shaft.
Is provided. The screw screw 6 extends to the vicinity of the wall surface 9 at the bottom of the silo 2, and a bottom plate 7 is provided at a lower end thereof. The bottom plate 7 is fixed to a wall surface 9 and supports the lower end of the screw 6. The screw of the screw 6 is formed relatively gently.

A screw-shaped weight body 8 is attached to the screw 6.
Is provided. The weight body 8 has a screw hole 11 for screwing with the screw 6 and a through hole 12 for a rod 15 to be described later to penetrate.

The shape of the weight body 8 is not limited to a disk shape but may be a polygonal shape. Further, it may have a conical shape extending upward. According to this, it is possible to prevent the stored goods 23 from being piled up on the weight body 8.

On the side of the screw 6, a rod 15 is provided as rotation preventing means 14 for preventing the weight body 8 from rotating with the rotation of the screw 6.
The rod 15 is arranged in parallel with the screw 6, the upper end of which is fixed to the support 5, and the lower end of which is fixed to the bottom plate 7.

The rotation preventing means 14 is composed of the rod 15 and the through hole 12 of the weight body 8.
Is prevented from rotating, so that the weight body 8 moves up and down in accordance with the rotation of the screw 6.

The motor 3 has a rotary encoder 17 as a rotation angle measuring means 16 for measuring the rotation angle of its rotating shaft.
Is provided.

A drive torque detecting means 18 for detecting a change in the drive torque of the motor 3 is provided on the support base 5, and a detection signal from the drive torque detection means 18 is received by the rotary encoder 17. A controller 21 having a level calculator 19 for calculating the level of the weight body 8 at that position from the rotation angle of the screw 6 is provided.

The drive torque detecting means 18 detects a change in current flowing through the motor 3 to detect a change in drive torque.

Next, an operation state of the screw type sounding level meter 1 having the above configuration will be described with reference to a flowchart shown in FIG.

First, the rotation of the screw 3 is started to be counted by the rotary encoder 17 simultaneously with the start of the forward rotation of the motor 3 (the direction in which the weight body 8 descends).

At this time, the weight body 8 attempts to rotate together with the rotation of the screw 6, but since the rotation is prevented by the rotation preventing means 14, the weight body 8 is
It is pushed down by the screw of and descends.

When the weight 8 descends to a position in contact with the storage 23 in the silo 2, the driving torque of the motor 3 increases because the weight 8 attempts to enter the storage 23.

The increase in the driving torque is detected by the driving torque detecting means 18 and the driving of the motor 3 is stopped. At this time, the count is read by the rotary encoder 17 and the rotation angle of the screw 6 is detected. This signal is sent to a level calculator 19, and the distance from the ceiling of the weight body 8, that is, the upper end face of the storage article 23 is calculated from the inclination angle and the rotation angle of the screw of the screw 6, and the level of the upper end face is calculated. Is calculated.

By the way, since the storage 23 in the silo 2 is powdery and is stacked at a predetermined angle of repose depending on the type, the position of the screw type sounding level meter 1 and its level are measured. Thus, the total storage amount can be calculated. Subsequently, when measuring the level, the motor 3 is started to rotate in the reverse direction (in the direction in which the weight body 8 rises), and the weight body 8 is slightly raised. This control is performed by managing the rotation angle or rotation time of the screw 6.

When the weight body 8 has risen a predetermined distance, the driving of the motor 3 is stopped. Then, at the same time as the normal rotation drive of the motor 3 is started again, the counting of the rotation angle of the screw 6 by the rotary encoder 17 is started.

Hereinafter, the same operation as described above is repeated.
It continues until the level measurement ends.

As described above, by calculating the level from the rotation angle of the screw 6, the next measurement can be prepared in a short time only by slightly raising the weight body 8, and the level can be continuously measured. It can be carried out.

Further, according to the above configuration, the weight body 8 is
Since the screw is screwed to the screw 6, it is securely supported. Also, since the screw 6 has high strength and does not break like a conventional metal tape, the weight body does not fall off. Absent.

Further, since the bottom plate 7 is provided at the lower end of the screw 6, even if the upper end surface of the stock 23 is lower than the lower end of the screw 6, the weight body 8 is silo. It does not fall into 2.

Further, since the bottom plate 7 is fixed to the bottom wall surface 9, the screw 6 and the rod 15 are fixed up and down. Measurement at various levels,
The fixing strength is improved.

In the above embodiment, by detecting a change in the current flowing through the motor 3 and a change in the driving torque, the weight body 8 comes into contact with the upper end surface of the storage 23 in the silo 2. Is detected, but the present invention is not limited to this. When the weight body 8 comes into contact with the storage product 23, a stress that pushes up the screw 6 is generated. By detecting this stress, it is detected that the weight body 8 comes into contact with the upper end surface of the storage product 23 in the silo 2. May be used.

Further, in the above embodiment, the example of measuring the level of the powdery storage material 23 has been described. However, if the weight body 8 is made lightweight and generates buoyancy, the liquid is stored in the tower tank. It can also be applied when stored.

[0041]

In summary, according to the present invention, there is provided an excellent effect that a member such as a weight body can be prevented from dropping into a storage and a level can be continuously measured. .

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of a screw type sounding level meter according to the present invention.

FIG. 2 is a side view showing an attached state of a screw type sounding level meter.

FIG. 3 is a flowchart showing an operation state of a screw type sounding level meter.

FIG. 4 is a sectional view showing a conventional sounding level meter.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 screw type sounding level meter 3 motor 5 support base 6 screw screw 8 weight body 12 through hole 14 rotation prevention means 15 rod body 16 rotation angle measurement means 18 drive torque detection means 19 level calculator 23 stock

Claims (2)

[Claims] 1. A sounding level meter for measuring a level of an upper end surface of a storage material in a tower tank for measuring a storage amount of the storage material in a tower tank, wherein the motor is provided on a ceiling portion of the tower tank in a vertical direction. A screw screw extending downwardly on the rotating shaft of the motor, a weight body screwed to the screw screw, a rotation preventing means for preventing the weight body from rotating together with the screw screw, A rotation angle measuring means for measuring the rotation angle of the screw, and detecting a change in the motor driving torque which increases when the weight body descends due to the rotation of the screw and comes into contact with the upper end surface of the stored object; Driving torque detecting means, and a level calculator which receives the detection signal of the driving torque detecting means and calculates the level of the weight body at that position from the rotation angle of the screw screw. Screw type sounding level meter. 2. A rod body in which the rotation preventing means is provided in parallel with the screw screw and whose upper end is fixed to a fixed system such as a motor support, and a rod body formed in the weight body and penetrated by the rod body. The screw-type sounding level meter according to claim 1, comprising a through hole.