CN114304721A - Asymmetric control method for cigarette weight - Google Patents
Asymmetric control method for cigarette weight Download PDFInfo
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- CN114304721A CN114304721A CN202210081903.1A CN202210081903A CN114304721A CN 114304721 A CN114304721 A CN 114304721A CN 202210081903 A CN202210081903 A CN 202210081903A CN 114304721 A CN114304721 A CN 114304721A
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Abstract
The invention provides an asymmetric control method of cigarette weight, which comprises the following steps: respectively setting a first linear relational expression and a second linear relational expression of the motion control of the wire pressing wheel corresponding to the positive deviation and the negative deviation of the cigarette weight. When the cigarette weight is in positive deviation, the wire pressing wheel is controlled to move downwards according to a first relational expression, wherein the first linear relational expression is as follows: Δ V1＝k1x1，ΔV1For amplitude of downward movement, x1Is the positive deviation of weight, k1Is the conversion coefficient of the downward motion amplitude. When the weight of the cigarette is negatively biased, controlling the wire pressing wheel to move upwards according to a second relation, wherein the second linear relation is as follows: Δ V2＝k2x2，ΔV2To an upward movement amplitude, x2As negative deviation of weight, k2Is the conversion coefficient of the upward motion amplitude. The invention can improve the accuracy of cigarette weight control, improve the quality and the resistance stability of cigarettes and reduce the consumption of tobacco shreds.
Description
Technical Field
The invention relates to the technical field of cigarette weight control, in particular to an asymmetric control method of cigarette weight.
Background
The cigarette weight is one of the most important physical indexes of the cigarette, and how to accurately control the weight on line is always the research focus of the tobacco industry at home and abroad. The existing weight control system is shown in figure 1, in a weight control loop, a density scanner detects the cigarette weight, feeds back an actual weight signal to a control system, compares the actual weight signal with a given weight, and controls an actuating mechanism to adjust a leveler to move up and down, so that the cigarette weight is controlled. In the position control loop, the displacement of the actuating mechanism is fed back to the control system through the displacement sensor and is compared with a position signal set by the leveler, the cigarette weight is further corrected, and the control period is basically within 40 ms. The existing cigarette making machine adopts a cut tobacco suction forming mode, and the cut tobacco is absorbed on a cut tobacco suction belt through negative pressure and finally cut after forming cigarette strips. As shown in fig. 2, the closer the cut tobacco is to the surface of the cut tobacco suction belt, the stronger the adsorption force is, the greater the natural density is, and the whole density distribution is in a condition of being dense at the top and sparse at the bottom. When the cigarettes are heavier, the tobacco pressing wheel moves downwards to reduce the tobacco shreds, but because the density of the lower part is relatively lower and the upward resistance brought to the downward movement of the tobacco pressing wheel by the flattening disc and the tobacco shreds is considered, the required downward stroke of the tobacco pressing wheel is larger when the positive deviation with the same absolute value is overcome; when the cigarette is lighter, the tobacco pressing wheel moves upwards to increase the tobacco shreds, but the upper density is relatively higher, and resistance does not need to be considered, so that the required upward stroke of the tobacco pressing wheel is smaller when the same deviation is overcome. When the wire pressing wheel moves upwards and downwards at equal intervals, the actual corresponding cigarette weight changes are unequal, which can generate a phenomenon of 'control unbalance', so that the number of heavy cigarettes in cigarette production is always larger than that of light cigarettes.
Disclosure of Invention
The invention provides an asymmetric control method for cigarette weight, which solves the problem that the existing cigarette weight control system controls a tobacco pressing wheel to move upwards or downwards according to the cigarette weight, so that the control imbalance phenomenon exists, the number proportion of heavy cigarettes in production is large, the accuracy of cigarette weight control can be improved, the quality and the resistance suction stability of cigarettes are improved, and the tobacco shred consumption is reduced.
In order to realize the following purposes, the invention provides the following technical scheme:
an asymmetric control method for cigarette weight comprises the following steps:
respectively setting a first linear relational expression and a second linear relational expression of motion control of the wire pressing wheel corresponding to the positive deviation and the negative deviation of the cigarette weight;
when the cigarette weight is in positive deviation, the wire pressing wheel is controlled to move downwards according to a first relational expression, wherein the first linear relational expression is as follows: Δ V1＝k1x1，ΔV1For amplitude of downward movement, x1Is the positive deviation of weight, k1A conversion coefficient being a magnitude of the downward motion;
when the weight of the cigarette is negatively biased, controlling the wire pressing wheel to move upwards according to a second relation, wherein the second linear relation is as follows: Δ V2＝k2x2，ΔV2To an upward movement amplitude, x2As negative deviation of weight, k2Is the conversion coefficient of the upward motion amplitude.
Preferably, the method further comprises the following steps:
randomly acquiring a plurality of groups of cigarettes continuously produced in a set number, and calculating to obtain the number ratio of the heavy cigarettes to the light cigarettes in each group;
judging whether the heavy cigarettes are continuously increased or not according to the quantity ratio of each group, and if so, increasing the conversion coefficient k of the downward motion amplitude1；
Judging whether the lighter cigarette is continuously increased or not according to the quantity ratio of each group, and if so, increasing the conversion coefficient k of the upward motion amplitude2。
Preferably, the method further comprises the following steps:
and acquiring the average weight of the cigarettes, calculating to obtain a difference value between the average weight and a set reference value, and if the difference value is in a control dead zone of a weight control system, keeping the existing position of the wire pressing wheel.
Preferably, the method further comprises the following steps:
and if the average weight is larger than the set reference value and the difference value is larger than the control dead zone, entering a positive deviation control mode, controlling the wire pressing wheel to move downwards, and controlling the movement amplitude according to the first linear relation.
Preferably, the method further comprises the following steps:
and if the average weight is smaller than the set reference value and the difference value is larger than the control dead zone, entering a negative deviation control mode, controlling the wire pressing wheel to move upwards, and controlling the movement amplitude according to the second linear relation.
Preferably, the conversion coefficient k is set1And k2The initial value of the cigarette is automatically corrected according to the proportion of the heavy cigarette and the light cigarette.
Preferably, the conversion coefficient k of the downward motion amplitude1Conversion factor k greater than the amplitude of upward motion2。
Preferably, judging whether the heavy cigarette or the light cigarette is continuously increased according to the quantity ratio comprises:
if the quantity ratio of each group is continuously increased, determining that the proportion of the heavy cigarettes in the set quantity is increased;
and if the quantity ratio of each group is continuously reduced, judging that the proportion of the lighter cigarettes in the set quantity is increased.
The invention provides an asymmetric control method of cigarette weight, which controls the downward or upward movement amplitude of a wire pressing wheel by respectively setting a first linear relation and a second linear relation corresponding to positive deviation and negative deviation of the cigarette weight. The problem of current cigarette weight control system according to cigarette weight control wire pressing wheel upward movement or downward movement have control unbalance is solved, cause the partial cigarette quantity proportion to account for than big in production is solved, the accuracy of cigarette weight control can be improved, the quality and the resistance to suction stability of cigarette are improved, the pipe tobacco consumption is reduced.
Drawings
In order to more clearly describe the specific embodiments of the present invention, the drawings to be used in the embodiments will be briefly described below.
Figure 1 is a schematic diagram of a conventional cigarette weight control system.
Fig. 2 is a schematic diagram of the conventional tobacco shred forming operation.
FIG. 3 is a schematic diagram of an asymmetric control method for cigarette weight according to the present invention.
FIG. 4 is a logic flow chart of asymmetric cigarette weight control provided by the present invention.
Detailed Description
In order to make the technical field of the invention better understand the scheme of the embodiment of the invention, the embodiment of the invention is further described in detail with reference to the drawings and the implementation mode.
The method aims at solving the problem that the quantity of heavy cigarettes is always larger than that of light cigarettes due to the phenomenon of unbalance control in the current cigarette production process. The invention provides an asymmetric control method for cigarette weight, which solves the problem that the existing cigarette weight control system controls a tobacco pressing wheel to move upwards or downwards according to the cigarette weight, so that the control imbalance phenomenon exists, the number proportion of heavy cigarettes in production is large, the accuracy of cigarette weight control can be improved, the quality and the resistance suction stability of cigarettes are improved, and the tobacco shred consumption is reduced.
As shown in fig. 3 and 4, an asymmetric control method for cigarette weight includes:
s1: respectively setting a first linear relational expression and a second linear relational expression of the motion control of the wire pressing wheel corresponding to the positive deviation and the negative deviation of the cigarette weight.
S2: when the cigarette weight is in positive deviation, the wire pressing wheel is controlled to move downwards according to a first relational expression, wherein the first linear relational expression is as follows: Δ V1＝k1x1，ΔV1For amplitude of downward movement, x1Is the positive deviation of weight, k1A conversion coefficient being a magnitude of the downward motion;
s3: when the weight of the cigarette is negatively biased, controlling the wire pressing wheel to move upwards according to a second relation, wherein the second linear relation is as follows: Δ V2＝k2x2，ΔV2To an upward movement amplitude, x2As negative deviation of weight, k2Is the conversion coefficient of the upward motion amplitude.
Specifically, two different linear conversion relations, namely positive conversion relation and negative conversion relation are set respectively aiming at positive deviation and negative deviation of cigarette weightThe deviation adopts a first linear relation as follows: Δ V1＝k1x1And controlling the tobacco pressing wheel to move downwards to reduce the tobacco shreds. The second linear relationship is adopted when negative deviation is negative: Δ V2＝k2x2Controlling the tobacco pressing wheel to move upwards to increase the tobacco shreds. The downward or upward movement of the wire pressing wheel is controlled through different linear relational expressions, the control unbalance phenomenon of a cigarette weight control system can be solved, the control precision is substantially improved, the suction resistance stability is improved, and the tobacco shred consumption is reduced.
The method further comprises the following steps:
s4: randomly acquiring a plurality of groups of cigarettes continuously produced in a set number, and calculating to obtain the number ratio of the heavy cigarettes to the light cigarettes in each group;
s5: judging whether the heavy cigarettes are continuously increased or not according to the quantity ratio of each group, and if so, increasing the conversion coefficient k of the downward motion amplitude1；
S6: judging whether the lighter cigarette is continuously increased or not according to the quantity ratio of each group, and if so, increasing the conversion coefficient k of the upward motion amplitude2。
In practical application, the k is finely adjusted according to the ratio of the number of heavy cigarettes to the number of light cigarettes of the previous certain number of cigarettes analyzed in real time1And k2When the heavy smoke continues to increase, the k continues to be increased1On the contrary, increase k2. At the same time, every time a certain number of cigarettes pass, k pairs1And k2Fine tuning is performed once.
The method further comprises the following steps: and acquiring the average weight of the cigarettes, calculating to obtain a difference value between the average weight and a set reference value, and if the difference value is in a control dead zone of a weight control system, keeping the existing position of the wire pressing wheel.
The method further comprises the following steps: and if the average weight is larger than the set reference value and the difference value is larger than the control dead zone, entering a positive deviation control mode, controlling the wire pressing wheel to move downwards, and controlling the movement amplitude according to the first linear relation.
The method further comprises the following steps: and if the average weight is smaller than the set reference value and the difference value is larger than the control dead zone, entering a negative deviation control mode, controlling the wire pressing wheel to move upwards, and controlling the movement amplitude according to the second linear relation.
Further, a conversion coefficient k is set1And k2The initial value of the cigarette is automatically corrected according to the proportion of the heavy cigarette and the light cigarette.
In practical application, when the cigarettes reach the set number threshold value, k is matched1And k2The value of (c) is fine-tuned once.
Further, the conversion coefficient k of the downward motion amplitude1Conversion factor k greater than the amplitude of upward motion2。
Further, according to quantity ratio judges whether heavy cigarette or light cigarette props up continuously, include:
if the quantity ratio of each group is continuously increased, determining that the proportion of the heavy cigarettes in the set quantity is increased;
and if the quantity ratio of each group is continuously reduced, judging that the proportion of the lighter cigarettes in the set quantity is increased.
In one embodiment, based on the ZJ118 cigarette making machine, the asymmetric control method of the cigarette weight control system is used for improving the control performance, solving the problem of unbalanced proportion of heavy cigarettes and light cigarettes and reducing the tobacco shred consumption. The product weight set point was 650 mg and the dead zone was controlled to 3 mg.
The method comprises the following specific steps:
1. setting an initial value, k1＝0.1，k2＝0.08。
2. The quantity ratio of the heavy cigarettes to the light cigarettes is calculated every hundred thousand cigarettes, and the proportion of the heavy cigarettes to the light cigarettes is 49.5%: 46.8%, the k can be increased further than if asymmetric control is not used1To 0.11.
3. Calculating the average weight of 32 cigarettes, comparing with a set value of 650 mg, and entering one of the following steps 4-6 according to the comparison result.
4. When the actual average weight is 652 mg, the difference from the set value of 650 mg is 2 mg, and the wire pressing wheel does not need to act within 3 mg of the control dead zone;
5. when the average weight is 664 mg, the difference from the set value of 650 mg is 14 mg, and the difference is more than 3 mg of the control dead zone, namely positive deviation, the wire pressing wheel moves downwards, and the movement amplitude is changed from delta V1＝k1x1Determination of Δ V in the examples10.11 × 14 is 1.54V, i.e., the amplitude of the downward movement of the presser wheel is 1.54 volts.
6. When the average weight is 636 mg, the difference from the set value of 650 mg is-14 mg, and the absolute value of the difference is more than 3 mg of the control dead zone, namely negative difference, the wire pressing wheel moves upwards, and the movement amplitude is changed from delta V2＝k2x2Determination of Δ V in the examples20.08 × 14 is 1.12V, i.e., the amplitude of the upward movement of the die wheel is 1.12 volts.
7. And completing one period, and entering the next cycle, namely entering the step 3 again.
To demonstrate the technical effect, the following comparative tests were carried out.
Comparing the models: two ZJ118 models;
the product specification is as follows: the target weight is 650 mg, and the dead zone is controlled to be 3 mg;
the comparison method comprises the following steps: both machines used the same cut tobacco batch, produced uniform specifications, and tracked the ratio of heavy to light tobacco for each of 10 production runs, as shown in table 1.
TABLE 1
The result shows that after the asymmetric control is used, the proportion difference between the heavy cigarette and the light cigarette is obviously reduced, the cigarette quality is better, and the tobacco shred consumption is lower.
Therefore, the invention provides an asymmetric control method of cigarette weight, which controls the downward or upward movement amplitude of the wire pressing wheel by respectively setting a first linear relation and a second linear relation corresponding to the positive deviation and the negative deviation of the cigarette weight. The problem of current cigarette weight control system according to cigarette weight control wire pressing wheel upward movement or downward movement have control unbalance is solved, cause the partial cigarette quantity proportion to account for than big in production is solved, the accuracy of cigarette weight control can be improved, the quality and the resistance to suction stability of cigarette are improved, the pipe tobacco consumption is reduced.
The construction, features and functions of the present invention have been described in detail with reference to the embodiments shown in the drawings, but the present invention is not limited to the embodiments shown in the drawings, and all equivalent embodiments modified or modified by the spirit and scope of the present invention should be protected without departing from the spirit of the present invention.
Claims (8)
1. An asymmetric control method for cigarette weight is characterized by comprising the following steps:
respectively setting a first linear relational expression and a second linear relational expression of motion control of the wire pressing wheel corresponding to the positive deviation and the negative deviation of the cigarette weight;
when the cigarette weight is in positive deviation, the wire pressing wheel is controlled to move downwards according to a first relational expression, wherein the first linear relational expression is as follows: Δ V1＝k1x1，ΔV1For amplitude of downward movement, x1Is the positive deviation of weight, k1A conversion coefficient being a magnitude of the downward motion;
when the weight of the cigarette is negatively biased, controlling the wire pressing wheel to move upwards according to a second relation, wherein the second linear relation is as follows: Δ V2＝k2x2，ΔV2To an upward movement amplitude, x2As negative deviation of weight, k2Is the conversion coefficient of the upward motion amplitude.
2. The asymmetric control method for cigarette weight according to claim 1, further comprising:
randomly acquiring a plurality of groups of cigarettes continuously produced in a set number, and calculating to obtain the number ratio of the heavy cigarettes to the light cigarettes in each group;
judging whether the heavy cigarettes are continuously increased or not according to the quantity ratio of each group, and if so, increasing the conversion coefficient k of the downward motion amplitude1；
Judging whether the lighter cigarette is continuously increased or not according to the quantity ratio of each group, and if so, increasing the conversion coefficient k of the upward motion amplitude2。
3. The asymmetric control method for cigarette weight according to claim 2, further comprising:
and acquiring the average weight of the cigarettes, calculating to obtain a difference value between the average weight and a set reference value, and if the difference value is in a control dead zone of a weight control system, keeping the existing position of the wire pressing wheel.
4. The asymmetric control method for cigarette weight according to claim 3, further comprising:
and if the average weight is larger than the set reference value and the difference value is larger than the control dead zone, entering a positive deviation control mode, controlling the wire pressing wheel to move downwards, and controlling the movement amplitude according to the first linear relation.
5. The asymmetric control method for cigarette weight according to claim 4, further comprising:
and if the average weight is smaller than the set reference value and the difference value is larger than the control dead zone, entering a negative deviation control mode, controlling the wire pressing wheel to move upwards, and controlling the movement amplitude according to the second linear relation.
6. Asymmetric control method for cigarette weight according to claim 5, characterized in that the conversion coefficient k is set1And k2The initial value of the cigarette is automatically corrected according to the proportion of the heavy cigarette and the light cigarette.
7. According to claim 6The asymmetric control method of the cigarette weight is characterized in that the conversion coefficient k of the downward motion amplitude1Conversion factor k greater than the amplitude of upward motion2。
8. The asymmetric control method for cigarette weight according to claim 7, wherein judging whether the heavy cigarette or the light cigarette is continuously increased according to the number ratio comprises:
if the quantity ratio of each group is continuously increased, determining that the proportion of the heavy cigarettes in the set quantity is increased;
and if the quantity ratio of each group is continuously reduced, judging that the proportion of the lighter cigarettes in the set quantity is increased.
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Cited By (1)
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| CN116210953A (en) * | 2023-04-17 | 2023-06-06 | 浙江中烟工业有限责任公司 | Asymmetric sectional control method and device for cigarette weight |
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