Chain sheet screening and rejecting method and equipment

Abstract

The invention relates to a chain sheet screening and rejecting method and equipment, the equipment comprises a servo motor, a servo belt line, a chain sheet sensing photoelectric sensor, a visual sensor, a first rejecting station and a second rejecting station, the chain sheet is conveyed through the servo belt line, and meanwhile, the numerical value of an encoder, related to the position, of the belt line at any moment is read through a PLC; and performing classification according to shot pictures through distance judgment and a visual sensor. And once defective products are found, the defective products are removed at the corresponding removing stations, and different types of defective products cannot flow back again, so that the screening efficiency is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of chain sheet processing, and in particular to a chain sheet screening and rejection method and equipment. Background Art

[0002] Chain pieces are parts of products such as chains. During the processing of chain pieces, unqualified products need to be eliminated, and visual systems are usually used for judgment. At present, the common visual sensor screening algorithm is a two-class classification method, that is, it is divided into OK products (good products) and defective products. After the defective products are detected and identified, they are eliminated by the rejection station. However, in actual production, there may be a need for multiple classifications of chain pieces, that is, they may be divided into multiple situations such as Class 0, Class 1, Class 2, etc., and they need to be eliminated according to different categories. In other words, in addition to OK products, there may be multiple defects in chain pieces, such as reverse chain pieces, scratched chain pieces, mixed chain pieces, etc., among which the reverse chain pieces need to be returned to the silo for secondary screening, while scratched chain pieces and mixed chain pieces need to be eliminated. The existing technology cannot meet the above needs. Summary of the invention

[0003] In order to solve the problems of the prior art, the present invention provides a chain sheet screening and rejection method and equipment which can output the results of chain sheet detection in multiple categories, thereby releasing OK products and rejecting different types of defective phenomena at corresponding workstations.

[0004] The specific technical solution is as follows: A chain piece screening and rejection method comprises the following steps:

[0005] S100: The chain piece is transmitted through the servo belt line, and the encoder value related to the belt line and position at any time is read through the PLC, which is recorded as Cn;

[0006] S200: When the chain passes through the photoelectric sensor, at the first moment when the sensor is ON, read the servo motor encoder value, and set the first reading as C0; it can be known that the number of encoder pulses corresponding to the chain from the photoelectric sensor to the visual sensor is D0, the number of pulses from the visual sensor to the first rejection station is D1, and the number of pulses from the first rejection station to the nth rejection station is Dn. By analogy, the distance from the visual sensor to the first rejection station is D1, and the distance from the visual sensor to the nth rejection station is D1+Dn;

[0007] S300: setting a loop variable T, that is, when the Tth chain piece is detected, the variable becomes 0 again, and at this time, the earliest first chain piece has passed the visual sensor;

[0008] S400: When the photoelectric sensor senses the arrival of the chain for the first time, the PLC reads the current driver feedback pulse value, recorded as C0, and adds the distance D0 from the photoelectric sensor to the visual sensor, and records this data as E0=C0+D0 for storage; if the second chain arrives, C1+D0 is assigned to E1 until ET is assigned. At this time, the PLC continuously compares the current pulse Cn with E0, E1...ET. When Cn>any one of {E0, E1...ET}, a photo signal is triggered;

[0009] S500: The visual sensor classifies the images taken, releases good products, and transports different types of defective products to different rejection stations for rejection.

[0010] In some embodiments, in step S400, if it is found that the photographed image is not in the center, the size of D0 can be adjusted so that the photographed image is in the center of the field of view.

[0011] In some embodiments, in step S500, if there are two reject stations, namely the first reject station and the second reject station, if the chain piece is to be transported to the first reject station, the current pulse value C0+D1 is assigned to a variable F0, and if the chain piece is to be transported to the second reject station, C0+D1+D2 is assigned to the variable G0. The PLC continuously compares the current pulse Cn with {F0-Fn} and {G0-Gn}. When Cn is greater than the above values, an action pulse is generated.

[0012] In some embodiments, the PLC is a PLC that can read the AB phase pulses of the encoder, and a variable Cn is set to store the current pulse value.

[0013] In some embodiments, the variable T is 5, that is, when the fifth chain piece is detected, the variable becomes 0 again, and at this time, the earliest first chain piece has passed the visual sensor.

[0014] In some embodiments, the belt speed of the servo belt line, the photoelectric trigger delay value of the photoelectric sensor, and the distances D0, D1, and D2 are adjustable.

[0015] In some embodiments, in step S500, let the OK product be M0, the reverse side be M1, and the poor appearance or defect be M2. If the chain piece inspection result is M0, it is released; if the result is M1, the cylinder pushes the chain piece out when it passes the first rejection station; if the result is M2, the chain piece is pushed out when it runs to the second rejection station, and the chain piece does not move when it passes the first rejection station.

[0016] A device using a chain sheet screening and rejection method, wherein the photoelectric sensor, the visual sensor and the rejection station are sequentially arranged at intervals along the transmission direction of a servo belt line.

[0017] In some embodiments, a chain input area is provided at one end of the servo belt line, and a good product release area is provided at the other end.

[0018] In some embodiments, the servo belt lines are arranged along a straight line.

[0019] The technical effect of the present invention is that compared with the prior art, which can only classify the chain pieces into two types, some defective products will flow back to the silo, and ineffective screening will be performed continuously, which greatly reduces the screening efficiency and increases the possibility of misselection. However, by adopting the technical solution of the present invention, once defective products are found, they will be rejected at the corresponding rejection station, and different types of defective products will not flow back again, which greatly improves the screening efficiency; it can realize the release of OK products, and different types of defective phenomena can be rejected at the corresponding stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a device layout diagram corresponding to the chain sheet screening and rejection method according to an embodiment of the present invention.

[0022] Figure 2 It is a schematic diagram of a chain sheet screening and rejection device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] In the description of the present invention, it should be noted that the terms "center," "up," "down," "left," "right," "vertical," "horizontal," "inside," "outside," etc., indicating positions or positional relationships, are based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operate in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first," "second," and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0025] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0027] like Figure 1 As shown, a chain piece screening and rejection method of the present embodiment includes the following steps: S100: transmitting the chain piece through the servo belt line, and reading the encoder value related to the belt line and the position at any time through the PLC, which is recorded as Cn; S200: when the chain piece passes through the photoelectric sensor, at the first moment when the sensor is ON, read the servo motor encoder value, and set the first reading as C0; it can be known that the number of encoder pulses corresponding to the chain piece from the photoelectric sensor to the visual sensor is D0, the number of pulses from the visual sensor to the first rejection station is D1, and the number of pulses from the first rejection station to the nth rejection station is Dn, and so on, the distance from the visual sensor to the first rejection station is D1, and the distance from the visual sensor to the nth rejection station is D1+Dn; S300: setting a loop variable T, that is, detecting the nth rejection station. When the T-piece chain arrives, this variable becomes 0 again, and at this time the earliest first piece of chain has passed the visual sensor; S400: when the photoelectric sensor senses the arrival of the chain for the first time, the PLC reads the current driver feedback pulse value, recorded as C0, and adds the distance D0 from the photoelectric sensor to the visual sensor, and records this data as E0=C0+D0 for storage; if the second piece of chain arrives, C1+D0 is assigned to E1 until ET is assigned. At this time, the PLC continuously compares the current pulse Cn with E0, E1...ET. When Cn>any one of {E0, E1...ET}, a photo signal is triggered; S500: The visual sensor classifies the products according to the photos, releases the good products, and transports different types of defective products to different rejection stations for rejection.

[0028] The above technical solution can solve the multi-classification problem of chain pieces in visual inspection, that is, in addition to OK products (good products), there may be multiple defects in the chain pieces, such as reverse chain pieces, scratched chain pieces, mixed chain pieces, etc., among which the reverse chain pieces need to be returned to the silo for secondary screening, while the scratched chain pieces and mixed chain pieces need to be removed. This method can be used to release OK products, and different types of defects can be removed at the corresponding workstations.

[0029] In this embodiment, in step S400, if it is found that the photographed image is not in the center, the size of D0 can be adjusted so that the photographed image is in the center of the field of view, thereby facilitating image recognition and judgment. In step S500, if there are two rejection stations, namely the first rejection station and the second rejection station, if the chain is to be transported to the first rejection station, the current pulse value C0+D1 is assigned to a variable F0, and if the chain is to be transported to the second rejection station, C0+D1+D2 is assigned to the variable G0. The PLC continuously compares the current pulse Cn and the sizes of {F0-Fn} and {G0-Gn}. When Cn is greater than the above values, an action pulse is generated. The PLC is a PLC that can read the encoder AB phase pulse, and a variable Cn is set to store the current pulse value.

[0030] In this embodiment, the variable T is 5, that is, when the fifth chain piece is detected, the variable becomes 0 again, and at this time, the earliest first chain piece has passed the visual sensor. The belt speed of the servo belt line, the photoelectric trigger delay value of the photoelectric sensor, and the distances D0, D1, and D2 are adjustable. By adjusting the parameters, a balance is achieved between conveying, identifying, and rejecting.

[0031] In this embodiment, in step S500, let the OK product be M0, the reverse side be M1, and the poor appearance or defect be M2. If the inspection result of the chain piece is M0, it is released; if the result is M1, the cylinder pushes the piece out when the chain piece passes the first rejection station; if the result is M2, the chain piece is pushed out when it runs to the second rejection station, and the chain piece does not move when it passes the first rejection station.

[0032] like Figure 2 As shown, this embodiment is further described below in conjunction with the chain sheet screening and rejection device of this embodiment.

[0033] This equipment takes the release of OK products and the addition of two defective product rejection stations as an example. This equipment includes a servo motor 1, a servo belt line 2, a chain sensing photoelectric sensor 3, a visual sensor 4, a first rejection station 5, and a second rejection station 6. The servo belt line is used to transmit the chain conveyed from the vibration plate. At the same time, the encoder value related to the belt line and the position at any time may be read through the PLC, which is recorded as Cn. When the chain passes through the photoelectric sensor, the photoelectric sensor generates a square wave, which is ON when the chain passes and OFF when the chain disappears. At the first moment when the photoelectric sensor is ON, read the servo motor encoder value, and set the first reading as C0. It can be known that the number of encoder pulses corresponding to the chain from the photoelectric sensor to the visual sensor is D0, the number of pulses from the visual sensor to the first rejection station 5 is D1, and the number of pulses from the first rejection station 5 to the second rejection station 6 is D2. Then the distance from the visual sensor to the first rejection station is D1, and the distance from the visual sensor to the second rejection station 6 is D1+D2. Since the distance from the photoelectric sensor to the visual sensor is a fixed value, a loop variable can be set according to the actual situation. Of course, the closer the photoelectric sensor is to the visual sensor, the better. Set the variable to 5, that is, when the fifth chain is detected, this variable becomes 0 again, and at this time the earliest first chain has passed the visual sensor. When the photoelectric sensor senses the arrival of the chain for the first time, the PLC reads the current driver feedback pulse value, recorded as C0, and adds the distance D0 from the photoelectric sensor to the visual sensor, and records this data as E0=C0+D0 for storage. If the second chain arrives, C1+D0 is assigned to E1. . . . At this time, the PLC continuously compares the current pulse Cn with E0, E1...E4. When Cn> any one of {E0, E1...E4}, a photo signal is triggered. If it is found that the photo is not in the center, the size of D0 can be adjusted so that the photo image is in the center of the field of view. The visual sensor will classify according to the photo. Suppose that the OK product is M0, the reverse side is M1, and the appearance is poor or defective is M2. If the detection result of the chain piece is M0, it will be released; if the result is M1, the cylinder will push the chain piece out when it passes the rejection station 1; if the result is M2, the chain piece will be pushed out when it runs to the rejection position 2, and the chain piece will not move when it passes the rejection station 1. When the visual sensor gives a signal, it may be any one of M0, M1, and M2. If the signal is M0, it will not move, and the chain piece can be moved along the belt line; if the signal is M1, the current pulse value C0+D1 is assigned to a variable F0, and if the signal is M2, C0+D1+D2 is assigned to a variable G0. This principle is similar to the above steps. The PLC keeps comparing the current pulse Cn with {F0-F5} and {G0-G5}. When Cn is greater than the above values, an action pulse is generated. Through the above technical solution, chain pieces with different detection results can be cleverly classified and triggered at different workstations.

[0034] In this embodiment, the photoelectric sensor 3, the visual sensor 4 and the rejection station are arranged in sequence along the transmission direction of the servo belt line, so that the chain pieces are transported in a straight line. A chain piece input area is provided at one end of the servo belt line 2, and a good product release area 7 is provided at the other end. The chain pieces can be supplied through a vibration plate, and the servo belt line 2 is arranged along a straight line.

[0035] A chain piece screening and rejection method and device of the present embodiment adopts a PLC that can read the AB phase pulse of the encoder, and sets a variable Cn for storing the current pulse; sets the belt speed, photoelectric trigger delay value, distance D0, D1, D2 and other parameters on the human-machine interface, and is adjustable; observes while taking pictures, and adjusts the D0 value so that the image is in the center of the field of view; adjusts the D1 and D2 values ​​so that the rejection station rejects the chain piece just when it passes by, neither ahead nor behind; adjusts the belt speed, the faster the belt speed, the more chain pieces pass per unit time, and the higher the efficiency, but too fast a speed will cause blurred pictures, and the maximum speed is also affected by the response speed of the cylinder of the rejection station. By adjusting the parameters, the device reaches a balanced state.

[0036] The above is a description of a chain sheet screening and rejection method and device of the present invention, but the present invention is not limited to the above specific implementations, and various modifications or changes can be made as long as they do not depart from the scope of the claims. The present invention includes various modifications and changes within the scope of the claims.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A chain piece screening and rejection method, characterized in that: The following steps are involved: S100: The chain piece is transmitted through the servo belt line, and the encoder value related to the belt line and position at any time is read through the PLC, which is recorded as Cn; S200: When the chain passes through the photoelectric sensor, at the first moment when the sensor is ON, read the servo motor encoder value, and set the first reading as C0; it can be known that the number of encoder pulses corresponding to the chain from the photoelectric sensor to the visual sensor is D0, the number of pulses from the visual sensor to the first rejection station is D1, and the number of pulses from the first rejection station to the nth rejection station is Dn. By analogy, the distance from the visual sensor to the first rejection station is D1, and the distance from the visual sensor to the nth rejection station is D1+Dn; S300: setting a loop variable T, that is, when the Tth chain piece is detected, the variable becomes 0 again, and at this time, the earliest first chain piece has passed the visual sensor; S400: When the photoelectric sensor senses the arrival of the chain for the first time, the PLC reads the current driver feedback pulse value, recorded as C0, and adds the distance D0 from the photoelectric sensor to the visual sensor, and records this data as E0=C0+D0 for storage; if the second chain arrives, C1+D0 is assigned to E1 until ET is assigned. At this time, the PLC continuously compares the current pulse Cn with E0, E1...ET. When Cn>any one of {E0, E1...ET}, a photo signal is triggered; S500: The visual sensor classifies the images taken, releases good products, and transports different types of defective products to different rejection stations for rejection.

2. The chain sheet screening and rejection method according to claim 1, characterized in that: In step S400, if it is found that the photographed image is not in the center, the size of D0 can be adjusted so that the photographed image is in the center of the field of view.

3. The chain sheet screening and rejection method according to claim 2, characterized in that: In step S500, if there are two reject stations, namely the first reject station and the second reject station, if the chain piece is to be transported to the first reject station, the current pulse value C0+D1 is assigned to a variable F0, and if the chain piece is to be transported to the second reject station, C0+D1+D2 is assigned to a variable G0. The PLC continuously compares the current pulse Cn with {F0-Fn} and {G0-Gn}. When Cn is greater than the above values, an action pulse is generated.

4. The chain sheet screening and rejection method according to claim 3, characterized in that: The PLC is a PLC that can read the AB phase pulses of the encoder, and a variable Cn is set to store the current pulse value.

5. The chain piece screening and rejection method according to claim 4, characterized in that: The variable T is 5, that is, when the fifth chain piece is detected, the variable becomes 0 again, and at this time, the earliest first chain piece has passed the visual sensor.

6. The chain piece screening and rejection method according to claim 5, characterized in that: The belt speed of the servo belt line, the photoelectric trigger delay value of the photoelectric sensor, and the distance D0, D1, and D2 parameters are adjustable.

7. The chain sheet screening and rejection method according to claim 6, characterized in that: In step S500, let the OK product be M0, the reverse side be M1, and the poor appearance or defect be M2. If the chain piece inspection result is M0, it is released; if the result is M1, the cylinder pushes the chain piece out when it passes the first rejection station; if the result is M2, the chain piece is pushed out when it runs to the second rejection station, and it does not move when it passes the first rejection station.

8. A device using the chain piece screening and rejection method according to any one of claims 1 to 7, characterized in that: The photoelectric sensor, the visual sensor and the rejection station are arranged in sequence and at intervals along the transmission direction of the servo belt line.

9. The chain sheet screening and rejection device according to claim 8, characterized in that: A vibration plate is provided at one end of the servo belt line, and a good product release area is provided at the other end.

10. The chain piece screening and rejection method according to claim 9, characterized in that: The servo belt lines are arranged along a straight line.

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