Elevator control method and control device based on material position

Abstract

The application discloses a kind of based on material position's elevator control method and control device, control method includes: the material height in the metering tank is obtained;Determine the lifting frequency f of the elevator when material height is located in the middle material position of metering tank;According to material height is located between high material position and middle material position of metering tank, determine the actual frequency of elevator;According to material height is located between low material position and middle material position of metering tank, determine the actual frequency of elevator.The application can make the feeding frequency of elevator realize endless adjustment, and at the same time solve the problem of frequent start-stop of elevator and insufficient feeding or metering tank plugging.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tobacco processing, in particular to a hoist control method and device based on material position. BACKGROUND

[0002] In the production process of tobacco, in order to ensure the stability of the material flow on the electronic belt scale, a metering tank is generally set in front of the electronic belt scale in advance, thereby playing a role of storing the material and regulating the flow of the material entering the electronic belt scale. In order to reduce the fluctuation of the flow, the stability of the material flow in the metering tank is crucial. The control mode of the metering tank in the prior art is to install two pairs of material detection photoelectric tubes on the outer wall of the metering tank, and to control the start-stop and speed of the hoist through the material level in the metering tank. Specifically, a pair of photoelectric tubes is arranged at the low material level and the high material level, respectively. When the material is below the low material level, the hoist runs at a high frequency; when the material is above the high material level, the hoist stops running and the hoist stops feeding; when the material is between the low material level and the high material level, the hoist runs at a constant frequency at a low frequency.

[0003] However, the existing control mode is too single, which only controls the running speed of the upstream hoist by setting a fixed frequency. However, the running frequency of the hoist is switched back and forth between high and low frequencies, which is easy to cause blockage or insufficient flow of the metering tank, even causing material breakage, and the hoist frequently starts and stops, resulting in a high failure rate of the hoist. SUMMARY

[0004] The present application aims to solve the problem that the running frequency of the hoist in the prior art is switched back and forth between high and low frequencies, which is easy to cause blockage or insufficient flow of the metering tank, even causing material breakage, and the hoist frequently starts and stops, resulting in a high failure rate of the hoist. The present application provides a hoist control method and device based on material position, which can realize stepless adjustment of the feeding frequency of the hoist, and solve the problems of frequent start-stop of the hoist and insufficient feeding or blockage of the metering tank.

[0005] To solve the above technical problems, the embodiments of the present application provide a hoist control method based on material position. The downstream equipment of the hoist is sequentially provided with a metering tank and an electronic belt scale. The metering tank is vertically arranged. The top end of the hoist is connected with the upper slot of the metering tank. The bottom of the metering tank is connected with the electronic belt scale. The metering tank includes three levels of high material level, middle material level and low material level. The control method comprises:

[0006] obtaining the material height in the metering tank;

[0007] determining the hoist lifting frequency f corresponding to the material height at the middle material level of the metering tank;

[0008] According to the material height between the high material level and the middle material level of the metering tank, the actual frequency F of the elevator is determined as: F=f*(1-h / h1);

[0009] According to the material height between the low material level and the middle material level of the metering tank, the actual frequency F of the elevator is determined as: F=f+(f max -f)*h / h2;

[0010] Wherein, f represents the lifting frequency of the elevator corresponding to the material height at the middle material level, f max represents the maximum lifting frequency of the elevator, h1 represents the height difference between the high material level and the middle material level, h2 represents the height difference between the middle material level and the low material level, and h represents the absolute value of the height difference between the material height in the metering tank and the middle material level.

[0011] According to another specific embodiment of the present application, it further comprises:

[0012] According to the material height above the high material level, the lifting frequency of the elevator is determined as 0;

[0013] According to the material height below the low material level, the lifting frequency of the elevator is determined as f max .

[0014] According to another specific embodiment of the present application, when the material height is at the middle material level of the metering tank, the feeding flow of the elevator is equal to the output flow set by the electronic belt scale.

[0015] According to another specific embodiment of the present application, the lifting frequency f of the elevator corresponding to the material height at the middle material level of the metering tank is determined, comprising:

[0016] Determine the weight of the material per unit length of the elevator;

[0017] Obtain the running speed of the elevator through the weight of the material per unit length of the elevator and the instantaneous feeding flow of the elevator;

[0018] Obtain the rotating speed of the elevator according to the running speed of the elevator;

[0019] Obtain the lifting frequency f according to the rotating speed of the elevator:

[0020] f=m*i*p / 60*ρ*a*l*R*π

[0021] Wherein, ρ represents the material density, a represents the material thickness of the elevator, l represents the material width of the elevator, m is the feeding flow of the elevator per unit time, i represents the transmission ratio of the motor reducer of the elevator, and p represents the pole pair number of the rotating magnetic field of the motor of the elevator.

[0022] According to another specific embodiment of the present application, a light barrier or a bar code is arranged on the inner side wall of the metering tank to obtain the material height in the metering tank.

[0023] The embodiment of the present application also provides a material position-based elevator control device, wherein a metering tank and an electronic belt scale are sequentially arranged in a downstream device of an elevator, the metering tank is vertically arranged, the top end of the elevator is connected with the upper opening of the metering tank, the bottom of the metering tank is connected with the electronic belt scale, the metering tank comprises three material levels, i.e., a high material level, a middle material level and a low material level, and the control device comprises:

[0024] a height obtaining unit, configured to obtain the material height in the metering tank;

[0025] a middle material level lifting frequency determining unit, configured to determine the lifting frequency f of the elevator when the material height is located at the middle material level of the metering tank;

[0026] a first actual frequency determining unit, configured to determine the actual frequency F of the elevator as F=f*(1-h / h1) when the material height is located between the high material level and the middle material level of the metering tank;

[0027] a second actual frequency determining unit, configured to determine the actual frequency F of the elevator as F=f+(f max -f)*h / h2 when the material height is located between the low material level and the middle material level of the metering tank.

[0028] wherein f represents the lifting frequency of the elevator when the material height is located at the middle material level, f max represents the maximum lifting frequency of the elevator, h1 represents the height difference between the high material level and the middle material level, h2 represents the height difference between the middle material level and the low material level, and h represents the absolute value of the height difference between the material height in the metering tank and the middle material level.

[0029] According to another specific embodiment of the present application, the control device further comprises:

[0030] a high material level lifting frequency determining unit, configured to determine the lifting frequency of the elevator as 0 when the material height is located above the high material level;

[0031] a low material level lifting frequency determining unit, configured to determine the lifting frequency of the elevator as f max when the material height is located below the low material level.

[0032] According to another specific embodiment of the present application, in the middle material level lifting frequency determining unit, the feeding flow of the elevator is equal to the output flow set by the electronic belt scale when the material height is located at the middle material level of the metering tank.

[0033] According to another specific embodiment of the present application, the middle material level lifting frequency determining unit comprises:

[0034] a weight determining sub-unit configured to determine the weight of the material per unit length of the elevator;

[0035] a running speed determining sub-unit configured to obtain the running speed of the elevator by the weight of the material per unit length of the elevator and the instantaneous feeding flow of the elevator;

[0036] a rotating speed determining sub-unit configured to obtain the rotating speed of the elevator according to the running speed of the elevator;

[0037] a lifting frequency determining sub-unit configured to obtain the lifting frequency f of the elevator according to the rotating speed of the elevator;

[0038] f = m * i * p / 60 * p * a * l * R * p

[0039] wherein p represents the density of the material, a represents the thickness of the material of the elevator, l represents the width of the material of the elevator, m represents the feeding flow of the elevator per unit time, i represents the transmission ratio of the motor reducer of the elevator, and p represents the pole pair number of the rotating magnetic field of the motor of the elevator.

[0040] According to another specific embodiment of the present application, the material height detecting unit is a reflection grating or a bar code arranged on the inner wall of the metering tank, and is configured to obtain the material height in the metering tank.

[0041] According to the elevator control method and device based on the material position provided by the present application, the actual material height of the material is obtained, the lifting frequency of the elevator when the material is located at the middle position is determined, the actual lifting frequency of the elevator is determined according to the actual material height of the material and the material height position of the middle position, the feeding frequency of the elevator can be infinitely adjusted, the feeding flow of the material can be continuously adjusted according to the actual position of the material, the material in the metering tank is always located at the middle space, the stability of the feeding flow is ensured, the flow fluctuation and the material breakage are avoided, and the problem of frequent start and stop of the elevator is solved. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 a flow chart of the elevator control method based on the material position provided by an embodiment of the present application is shown;

[0043] Figure 2 a block diagram of the elevator control device based on the material position provided by an embodiment of the present application is shown. DETAILED DESCRIPTION

[0044] The following detailed description together with the accompanying drawings will provide a fuller understanding of the application. Although the application is described with reference to the preferred embodiment, those skilled in the art will readily appreciate that the detailed description and drawings are by way of illustration only. Merely by way of example, the description of the application is not intended to limit the scope of the application to particular embodiments described herein. The description of the application together with the drawings will provide those of ordinary skill in the art with a complete understanding of the application. The application is intended to cover all alternatives, modifications and equivalents thereof. The application includes various steps, which have been described in serial order. However, it will be understood that the ordering of steps is not limiting. Certain steps can be performed in different orders and / or concurrently with other steps. Furthermore, it will be understood that some steps can be optional based on the circumstances. The use of certain terms in various places in the specification is for the purpose of that use in that place, and is not intended to limit or to imply a possible ranking or importance of claimed subject matter.

[0045] It should be noted that in this specification, similar reference numbers and letters in the following drawings represent similar items, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0046] The terms "first", "second", and the like, are used only to distinguish descriptions, and cannot be understood as indicating or implying relative importance.

[0047] In order to make the purpose, technical scheme and advantages of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the drawings.

[0048] As shown in Figure 1 The embodiments of the present application provide a material position-based elevator control method. Downstream equipment of the elevator is sequentially provided with a metering tank and an electronic belt scale. The metering tank is vertically arranged. A top end of the elevator is connected with an upper tank opening of the metering tank. A bottom of the metering tank is connected with the electronic belt scale. The metering tank includes three material levels, i.e., a high material level, a middle material level and a low material level. The control method includes the following steps:

[0049] S101, obtaining a material height in the metering tank;

[0050] S102, determining a lifting frequency f of the elevator corresponding to the material height located at the middle material level of the metering tank;

[0051] S103, determining an actual frequency F of the elevator according to the material height located between the high material level and the middle material level of the metering tank, as F=f*(1-h / h1);

[0052] S104, determining the actual frequency F of the elevator according to the material height located between the low material level and the middle material level of the metering tank, as F=f+(f max -f)*h / h2;

[0053] Wherein, f represents the lifting frequency of the elevator when the material height is located at the middle material level, f max represents the maximum lifting frequency of the elevator, h1 represents the height difference between the high material level and the middle material level, h2 represents the height difference between the middle material level and the low material level, and h represents the absolute value of the height difference between the material height in the metering tank and the middle material level.

[0054] By adopting the technical scheme, the actual material height of the material is acquired, the lifting frequency of the elevator when the material is located at the middle material level is determined, the actual lifting frequency of the elevator is determined according to the actual material height of the material and the material height position of the middle material level, the stepless adjustment of the feeding frequency of the elevator can be realized, the feeding flow of the material can be continuously adjusted according to the actual position of the material, the material in the metering tank can always be located at the middle space, the stability of the feeding flow is ensured, the flow fluctuation and the material breakage are avoided, and the problem of frequent start and stop of the elevator is solved.

[0055] Specifically, when the material height is between the high material level and the middle material level or between the low material level and the middle material level, the material height changes, the lifting frequency of the elevator is adjusted according to the actual height of the material, the stepless adjustment of the elevator is realized, the material height is always maintained between the low material level and the high material level, and the stability of the feeding flow is ensured.

[0056] Further, the inner side wall of the metering tank is provided with a reflection type grating or a bar code to acquire the material height in the metering tank.

[0057] Specifically, in the actual feeding process, due to the non-absolute uniformity of the material thickness on the elevator or the flow fluctuation of the front and rear process sections, the actual feeding flow is unstable, and the material height detection device is arranged to detect the position of the material in the metering tank. Optionally, the material height detection device is a reflection type grating or a bar code. Taking the bar code as an example, the bar code is installed on one side of the inner side wall of the metering tank, and a visual recognition device is installed on the other side. When the material falls into the metering tank, part of the bar code is shielded, the length of the bar code is recognized by the visual recognition device, and the actual material height of the material in the metering tank is determined.

[0058] Further, the control method further comprises:

[0059] According to the material height located above the high material level, the lifting frequency of the elevator is determined as 0;

[0060] According to the material height located below the low material level, the lifting frequency of the elevator is determined as f max .

[0061] Specifically, if the front end material of the elevator has a problem, at this time, the material height may be above the high material level, so the elevator needs to be stopped, at this time, the lifting frequency of the elevator is 0, so that the staff can find the problem; or the material height is below the low material level, so that the lifting frequency of the elevator is the rated maximum lifting frequency, so as to meet the material supply demand. Usually, the maximum lifting frequency of the elevator is 50Hz.

[0062] Further, when the material height is at the middle material level of the metering tank, the material supply flow of the elevator is equal to the output flow set by the electronic belt scale.

[0063] With this technical solution, the material supply of the elevator when the material height is at the middle material level is defined. Specifically, the lifting frequency of the elevator is set to meet the condition that the material supply flow is equal to the output flow set by the subsequent process, so that the material position of the elevator is always in the middle space, and the stability of the material supply flow is ensured.

[0064] Further, the lifting frequency f of the elevator corresponding to the material height at the middle material level of the metering tank is determined, including:

[0065] determining the weight of the material per unit length of the elevator;

[0066] obtaining the running speed of the elevator through the weight of the material per unit length of the elevator and the instantaneous material supply flow of the elevator;

[0067] obtaining the rotating speed of the elevator according to the running speed of the elevator;

[0068] obtaining the lifting frequency f according to the rotating speed of the elevator:

[0069] f=m*i*p / 60*ρ*a*l*R*π,

[0070] wherein ρ represents the material density, a represents the material thickness of the elevator, l represents the material width of the elevator, m is the material supply flow of the elevator per unit time, i represents the transmission ratio of the motor reducer of the elevator, and p represents the pole pair number of the rotating magnetic field of the motor of the elevator.

[0071] Specifically, the material thickness of the elevator is a, the material density of the elevator is ρ, and the material width of the elevator is l, so the weight of the material per unit length of the elevator m0 is:

[0072] m0=ρal,

[0073] The material supply flow of the elevator is set to be equal to the output flow set by the electronic scale, and the material supply flow of the elevator per unit time m is:

[0074] m=m0*v=ρalv,

[0075] The running speed v of the elevator is:

[0076] v = m / ρal.

[0077] The elevator comprises a motor, a motor reducer and a conveying belt, wherein the motor is connected with the motor reducer, the motor reducer is connected with the conveying belt through a transmission device, the running speed of the conveying belt is controlled by controlling the running frequency of the motor, and the feeding flow of the elevator is controlled.

[0078] If the transmission shaft diameter of the motor reducer is R and the transmission ratio is i, the rotation speed D0 of the motor reducer is:

[0079] D0 = v / (R*π),

[0080] The rotation speed D of the motor is obtained according to the rotation speed of the motor reducer:

[0081] D = D0*i = vi / (R*π)

[0082] The lifting frequency f of the elevator is obtained according to the relationship between the rotation speed and the frequency of the motor: D = 60f / p.

[0083] f = Dp / 60 = m*i*p / 60*ρ*a*l*R*π.

[0084]

EXAMPLE

[0085] The material thickness a of the elevator is 5 cm, the material density ρ of the elevator is 0.25 g / cm 3 , the material width l of the elevator is 1 m, and the material flow m0 of the unit length of the elevator is: m0 = pal = 5*0.25*1000 = 1250 g = 1.25 Kg. The electronic scale sets the flow to 3600 Kg / h, which is converted to seconds, so the set flow is m = 1 kg / s. The theoretical feeding speed v of the elevator is m / m0 = 0.8 s. According to the parameters of the motor and the reducer, the lifting frequency of the elevator when the material level is calculated is 20 Hz.

[0086] When the material height is between the medium material level and the low material level, if the absolute value of the height difference between the material position and the medium material level is 10 cm, and the height difference between the medium material level and the low material level is 20 cm, according to the formula F2 = f + (f max -f)h / h2 = 20 + (50-20)*10 / 20 = 35 Hz, the actual frequency of the elevator is 35 Hz.

[0087] When the material height is between the middle material level and the high material level, if the absolute value of the height difference between the material position and the middle material level is 10 cm, the height difference between the high material level and the middle material level is 20 cm, according to the formula F1=f*(1-h / h1)=20*(1-10 / 20)=10Hz, the actual frequency of the elevator is 10 Hz.

[0088] As shown in Figure 2 The embodiment of the application further provides an elevator control device based on a material position, downstream equipment of the elevator is sequentially provided with a metering tank and an electronic belt scale, the metering tank is vertically arranged, a top end of the elevator is connected with an upper tank opening of the metering tank, and a bottom of the metering tank is connected with the electronic belt scale, the metering tank comprises three material levels of a high material level, a middle material level and a low material level, and the control device comprises:

[0089] a height acquisition unit 201, configured to acquire a material height in the metering tank;

[0090] a middle material level lifting frequency determination unit 202, configured to determine a lifting frequency f of the elevator corresponding to the material height being located at the middle material level of the metering tank;

[0091] a first actual frequency determination unit 203, configured to determine an actual frequency F of the elevator as F=f*(1-h / h1) according to the material height being located between the middle material level and the high material level of the metering tank;

[0092] a second actual frequency determination unit 204, configured to determine the actual frequency F of the elevator as F=f+(f max -f)*h / h2 according to the material height being located between the low material level and the middle material level of the metering tank.

[0093] Wherein, f represents the lifting frequency of the elevator corresponding to the material height being located at the middle material level, f max represents the maximum lifting frequency of the elevator, h1 represents the height difference between the high material level and the middle material level, h2 represents the height difference between the middle material level and the low material level, and h represents the absolute value of the height difference between the material height in the metering tank and the middle material level.

[0094] Further, the control device further comprises:

[0095] a high material level lifting frequency determination unit, configured to determine the lifting frequency of the elevator as 0 according to the material height being located above the high material level;

[0096] a low material level lifting frequency determination unit, configured to determine the lifting frequency of the elevator as f max .

[0097] Further, in the middle material level lifting frequency determining unit, when the material height is at the middle material level of the metering tank, the feeding flow of the elevator is equal to the output flow set by the electronic belt scale.

[0098] Further, the middle material level lifting frequency determining unit comprises:

[0099] a weight determining sub-unit for determining the weight of the material per unit length of the elevator;

[0100] a running speed determining sub-unit for obtaining the running speed of the elevator by the weight of the material per unit length of the elevator and the instantaneous feeding flow of the elevator;

[0101] a rotating speed determining sub-unit for obtaining the rotating speed of the elevator according to the running speed of the elevator;

[0102] a lifting frequency determining sub-unit for obtaining the lifting frequency f according to the rotating speed of the elevator;

[0103] f = m * i * p / 60 * p * a * l * R * p,

[0104] wherein p represents the material density, a represents the material thickness of the elevator, l represents the material width of the elevator, m is the feeding flow of the elevator per unit time, i represents the transmission ratio of the motor reducer of the elevator, and p represents the pole pair number of the rotating magnetic field of the motor of the elevator.

[0105] Further, the material height detecting unit is a reflection grating or a bar code arranged on the inner wall of the metering tank, and is used for obtaining the material height in the metering tank.

[0106] Although the present application has been illustrated and described with reference to certain preferred embodiments thereof, it should be understood that the above description is intended to be illustrative only and not restrictive of the application. Many other changes in form and detail can be made to the application, without departing from the spirit and scope of the application.

Claims

1. A method of controlling an elevator based on the position of a material, characterized by, The downstream equipment of the elevator is sequentially provided with a metering tank and an electronic belt scale, the metering tank is vertically arranged, the top end of the elevator is connected with the upper opening of the metering tank, the bottom of the metering tank is connected with the electronic belt scale, the metering tank comprises three material levels of a high material level, a middle material level and a low material level, and the control method comprises the following steps: acquiring the material height in the metering tank; determining the lifting frequency f of the elevator corresponding to the middle material level of the metering tank when the material height is located at the middle material level; determining the actual frequency F of the elevator according to the material height located between the high material level and the middle material level of the metering tank, F = f * (1 - h / h1); According to the material height being located between the low material level and the middle material level of the metering tank, the actual frequency F of the elevator is determined as: F = f + (f max -f) * h / h2; wherein f represents the lifting frequency of the elevator corresponding to the material height located at the middle material level, f max represents the maximum lifting frequency of the elevator, h1 represents the height difference between the high material level and the middle material level, h2 represents the height difference between the middle material level and the low material level, and h represents the absolute value of the height difference between the material height in the metering tank and the middle material level.

2. The control method according to claim 1, characterized by, further comprising: determining the lifting frequency of the elevator as 0 according to the material height located above the high material level; According to the material height is located below the low material level, the lifting frequency of the elevator is determined as f max .

3. The control method according to claim 1, characterized by, when the material height is located at the middle material level of the metering tank, the feeding flow of the elevator is equal to the output flow set by the electronic belt scale.

4. The control method according to claim 3, characterized by, The determination of the lifting frequency f of the elevator corresponding to the middle material level of the metering tank comprises the following steps: determining the material weight per unit length of the elevator; obtaining the running speed of the elevator through the material weight per unit length of the elevator and the instantaneous feeding flow of the elevator; obtaining the rotating speed of the elevator according to the running speed of the elevator; obtaining the lifting frequency f of the elevator according to the rotating speed of the elevator: f = m * i * p / 60 * rho * a * l * R * pi wherein, rho represents the material density, a represents the material thickness of the elevator, l represents the material width of the elevator, m is the feeding flow of the elevator per unit time, i represents the transmission ratio of the motor reducer of the elevator, and p represents the pole pair number of the rotating magnetic field of the motor of the elevator.

5. The control method according to claim 1, characterized by, A light barrier or a bar code is arranged on the inner side wall of the metering tank to acquire the material height in the metering tank.

6. A material position based elevator control apparatus, characterized by, The downstream equipment of the elevator is sequentially provided with a metering tank and an electronic belt scale, the metering tank is vertically arranged, the top end of the elevator is connected with the upper opening of the metering tank, the bottom of the metering tank is connected with the electronic belt scale, the metering tank comprises three material levels of a high material level, a middle material level and a low material level, and the control device comprises: a height acquisition unit configured to acquire the material height in the metering tank; a middle material level lifting frequency determination unit configured to determine the lifting frequency f of the elevator corresponding to the middle material level of the metering tank when the material height is located at the middle material level; a first actual frequency determination unit configured to determine the actual frequency F of the elevator according to the material height located between the high material level and the middle material level of the metering tank, F = f * (1 - h / h1); a second actual frequency determining unit, configured to determine an actual frequency F of the elevator as F=f+(f max -f)*h / h2; wherein f represents the lifting frequency of the elevator corresponding to the material height located at the middle material level, f max represents the maximum lifting frequency of the elevator, h1 represents the height difference between the high material level and the middle material level, h2 represents the height difference between the middle material level and the low material level, and h represents the absolute value of the height difference between the material height in the metering tank and the middle material level.

7. The control device of claim 6, wherein further comprising: a high material level lifting frequency determination unit configured to determine the lifting frequency of the elevator as 0 according to the material height located above the high material level; a low material level lifting frequency determination unit configured to determine a lifting frequency f of the elevator when the material level is below the low material level max .

8. The control device of claim 6, wherein in the middle material level lifting frequency determination unit, when the material height is located at the middle material level of the metering tank, the feeding flow of the elevator is equal to the output flow set by the electronic belt scale.

9. The control device of claim 8, wherein The middle material level lifting frequency determination unit comprises: A weight determining subunit is configured to determine the weight of the elevator material per unit length; A running speed determining subunit is configured to obtain the running speed of the elevator by the weight of the elevator material per unit length and the instantaneous feeding flow of the elevator; A rotating speed determining subunit is configured to obtain the rotating speed of the elevator according to the running speed of the elevator; A lifting frequency determining subunit is configured to obtain the lifting frequency f according to the rotating speed of the elevator: f=m*i*p / 60*ρ*a*l*R*π wherein ρ represents the material density, a represents the material thickness of the elevator, l represents the material width of the elevator, m is the feeding flow of the elevator per unit time, i represents the transmission ratio of the motor reducer of the elevator, and p represents the pole pair number of the rotating magnetic field of the motor of the elevator.

10. The control device of claim 6, wherein Further comprising a material height detecting unit, which is a reflection type grating or a bar code arranged on the inner wall of the metering tank and is configured to obtain the material height in the metering tank.

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