JPS6353451A - Method and apparatus for detecting buckled can - Google Patents

Abstract

PURPOSE:To achieve an automatic and fast inspection of the presence of buckling, by making a judgment based on a difference in output signal corresponding to the shape of the circumferential surface of a can between adjacent sensors separately among proximity sensor groups provided along the axis of the can. CONSTITUTION:The shape of circumferential surface of a can 1 turning is measured with sensors S1-S3, S4-S6, S7-S9 and the like among proximity sensor groups 21-23. A buckling is detected with a control section 30 depending on a difference between an output of a sensor S2 set at such a position that buckling is the hardest to occur and outputs of the sensors S1 and S2 adjacent thereto exceeds a threshold. The same operation is performed for the sensor groups 22 and 23 thereby enabling automatic and fast inspection of the presence of a buckled can.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is directed to the treatment of buckled cans that occur during the manufacturing process of canned goods.
This invention relates to a method for automatically detecting buckled cans and its mounting.

[Prior Art] In the manufacturing process of canned goods, there is a process of performing neck-in processing and flange processing on one part of the can, and a process of wrapping the other lid after filling the empty cans with contents. etc., a large load may be applied in the axial direction of the can.

That is, in the process of winding and tightening the lid around the can body, the edge of Zi is rolled and tightened with a tightening roll while the lid is pressed and fixed to the can y by a zipper or the like. In addition, in the neck-in processing process, a load is applied in the axial direction by a drawing machine while squeezing the can [21 part] inward, and furthermore, in the flange processing process, a load is applied in the axial direction by a flange machine. The mouth of the can is opened outward.

For this reason, in the manufacturing process of canned goods, buckling often occurs in the can body.
Not only did it have poor aesthetics, significantly reducing the product price, but it also led to poor sealing, which was a major cause of defective canned goods. Furthermore, due to the phenomenon in which a portion of the can body protrudes due to buckling, there is a drawback that the can can become clogged during transportation during the can manufacturing process.

Therefore, it is necessary to detect buckling and sort it by length, but the biggest drawback of buckling is the loss of aesthetics. Conventionally, buckling has been detected by human visual inspection because there is no suitable method for detecting buckling.

[Problems to be Solved] As mentioned above, conventional buckling detection was performed by human visual inspection. For this reason, there are problems in that there are variations in the criteria for determining whether or not buckling occurs, and human detection errors due to worker fatigue or carelessness cannot be avoided, making highly accurate detection impossible. Ta. In addition, visual inspection by a worker makes it difficult to speed up the inspection, and there are also major problems in automating the inspection and, by extension, the can manufacturing process.

As shown in FIG. 5, by rotating the can 1 and measuring the change in the shape of the can in the circumferential direction, that is, the change in the distance between the proximity sensor 51 and the circumferential surface of the can 1, using the proximity sensor 51 etc. A method of inspecting the presence or absence of buckling may also be considered, but
In the case of this method, there is a risk that uneven rotation of the can or a change in the distance between the roundness sensor 51 and the circumferential surface of the can 1 may be mistaken for buckling, and the accuracy of detection may be reduced. There is a problem with this.

The present invention has been made in view of the above problems, and
By detecting buckling based on the output difference between axially adjacent proximity sensors, it is possible to speed up and automate inspections, and to enable accurate and high-precision buckling detection. The purpose of this research is to provide a method and device for detecting oxidation.

[Means for Solving the Problems] In order to achieve the above object, the method for detecting buckling of the present invention includes installing a plurality of proximity sensors at positions close to the cans that have been transferred to the inspection position by the transfer means. These proximity sensors are installed in parallel on the same line in the axial direction of the can -1-, and output signals corresponding to the circumferential shape of the can, and the can buckles based on the difference in signals between adjacent proximity sensors. Whether or not I
It should be separated.

Furthermore, the buckling detection device of the present invention includes means for transporting the can along the transport path, and a proximity sensor that outputs a signal corresponding to the circumferential shape of the can in proximity to the can on the transport path -1-. The can buckles based on the signal difference between the proximity sensor 4↑, which is a plurality of sensors arranged in parallel on the same line in the axial direction of the can, and the adjacent proximity sensor in this proximity sensor group. It consists of an ``I'' section that separates RL and RL.

Note that the single 5111 can also be used to detect cans with irregularities on the outer peripheral surface due to causes other than buckling, and can also be used for containers other than cans. Therefore, in the present invention, these can be detected. This is collectively referred to as buckling.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

First, an embodiment of the apparatus of the present invention will be described based on the drawings.

Fig. 1 is a schematic plan view of an embodiment in which the detection device is installed during the seaming process in step 4, Fig. 2 is a schematic configuration diagram of the same detection device, and Fig. 3
The figure shows the circuit configuration of the control section, and FIG. 4 shows the waveform diagram of the control section.

In the drawings, reference numeral 1 indicates a can as an object to be inspected for the presence or absence of buckling. 10 is Taref), and can 1 is placed on the outer periphery.
A plurality of carts 10a are provided at equal intervals for transporting the objects. This turret 10 rotates intermittently at a predetermined speed and transports the can 1 to the inspection position A. Each blur,)
A rotary table 11 is disposed at the bottom of 10a, and this rotary table 11 rotates when the can 1 is transferred to the inspection position i1A, and normally rotates each can 1 once. Reference numeral 12 denotes a front-stage auxiliary turret, which feeds the can l sent from the front process into the pocket 10a of the turret 10. Reference numeral 13 denotes a rear-stage auxiliary turret, which receives the can 1 from the turret 10, and transfers the can l sent from the front process into the pocket 10a of the turret 10. 14 is a timing sensor, when the can 1 is transferred to the inspection position A,
It outputs a signal when it is sent out from inspection position A. In addition, 15 is a pulse generator, and 13 is a rear stage auxiliary turret.
A pulse signal corresponding to the sending parameter is output based on the rotation speed of the motor.

SL, -, S9 are proximity sensors that output signals corresponding to the circumferential shape of the can 1, and in this embodiment, there are three proximity sensors S+, 32, S3 and sa, S5.

Three sets of proximity sensors 21, 22, and 23 are formed by setting S6, S7, Ss, and S9 as one set. These three proximity sensor groups 21, 22, 23 are
They are arranged in a plurality of rows near the can 1 at the inspection position A. The three proximity sensors in each proximity sensor group 21.degree. 22.23 are arranged in parallel on the same line in the axial direction (height direction) of the can at appropriate intervals. In this case, the axial arrangement t of each proximity sensor is such that the proximity sensors in the other two proximity sensor groups are positioned slightly shifted in the can circumferential direction between the proximity sensors in the - group of proximity sensor groups. It is supposed to be done.

That is, the proximity sensor Sl in the proximity sensor group 21
- Between S2 and 32-9l, there is a proximity sensor group 22.2
Proximity sensors S4.37 and 35.38 in proximity sensor group 21.3 are located between proximity sensors Sa-35 and 35-5b in proximity sensor group 22, and proximity sensor 32 in proximity sensor group 21.23 is located between proximity sensors Sa-35 and 35-5b in proximity sensor group 22.

S7 and S3. Furthermore, between the proximity sensors 5l-3s and Ss-39 in the proximity sensor group 23, the proximity sensors 32 and S5 in the proximity sensor group 21.22
, Sa and Sr are arranged so as to rub each other. As a result, the proximity sensor St is placed in the axial direction of the can 1.
, ~, Sq are placed ff densely.

In this embodiment, there are three proximity sensor groups, and each proximity sensor group has three proximity sensors, but it goes without saying that these can be increased or decreased as appropriate depending on the height and diameter of the can. It is also possible to change the number of proximity sensors in the - group or each group of proximity sensors.

As the proximity sensors S1, -, 39, various sensors such as a sensor that oscillates a high frequency, an optical sensor, or an eddy current sensor can be used.

Reference numeral 30 denotes a control unit that determines whether or not buckling has occurred based on signals sent from each proximity sensor Sl, -, 39. Here, in order to make the explanation easier to understand, the proximity switches S1 . A circuit system for processing signals sent from 32+33 will be explained. (The same applies to the circuit systems of the other two sets of proximity switches 122 and 23.) The circuit of the control section 30 includes the proximity switches S1 and 32, and S2.
and a subtracter 31a that calculates the difference between the signals output from S3 and S3.
, 31b, and M calculation'a 31 a.

Comparators 33a and 33b compare the value obtained at step 31b with the value preset in the setting device 32, and a signal from the timing sensor 14 that informs that the can 1 is at the inspection position 21A. , 33b, the gate circuit 34. a, 34b, and a discriminator 35 that discriminates whether buckling has occurred based on signals sent through the gate circuits 34a, 34b.

41 is a display device which displays whether the inspected can 1 is long or buckled based on a signal from the control unit 30, and also indicates whether buckling has occurred using signals from the timing sensor 14 or the like. Displays the pocket number etc. of the completed thali/ ). Reference numeral 42 designates a solenoid valve provided in the discharge air pipe 43, which is activated when the buckled Cfi is discharged from the conveyance line, and causes Nia to be ejected from the discharge air pipe 43 toward the discharge position B. The activation signal to this solenoid valve 42 is
It is stored in the shift register 44 described above to determine in advance how many times the buckling detected at the inspection position A is sent to the discharge position mB, and the pulse signal from the pulse generator 15 is is output when the shift register 44 counts that number.

Next, an example of the tree U IJ1 method will be described.

The cans 1 sent sequentially from neck-in processing, 7-lunge processing, seaming process, etc. are sent to the front auxiliary turret 1.
2, they are fed one by one into the pocket loa of the turret 10 and placed on the rotating table 11. As a result, :El is transferred to the inspection position A and rotated once by the rotary table 1 at the inspection position δA. The timing sensor 14 detects this movement and outputs test start and end signals to the gate circuits 34a and 34b.

Due to the rotation of the can 1, each proximity sensor St + S2.

S3 outputs a signal corresponding to the shape of the circumferential surface of the can 1 in the sleeve direction. The subtracter 31a is the proximity sensor S1
The subtracter 31b calculates the difference between the signals from the proximity sensors S2 and S3. Subtractor 31a
, 31b are calculated by the respective comparators 33a, 31b.
33b, it is compared with a preset value from the setting device 32.

Now, there is buckling in the upper part of the can 1, and the output value of the subtractor 31a changes beyond the allowable range of the set value.

Comparator 33a outputs a buckling detection signal. When this buckling detection signal is output by a signal from the timing sensor 14 while the gate circuit 34a is open, that is, while the can is being inspected, the discriminator 35 inputs this signal.

The discriminator 35 is one of the comparators 33a.

When a buckling detection signal is input from 33b, . Display. At the same time, the buckling detection signal is stored in the shift register 44.

When the inspection is completed in this way, the can 1 that has been inspected is
are sequentially transferred by the turret 10, and transferred to the rear auxiliary turret 1.
3, the cans are sent to the conveyance line for the next process, and if the inspection result is that buckling is detected, the number of cans sent to the discharge position B is counted by the shift register 44 (for example, by timing detection). When the buckling reaches the discharge position 21B of the conveyor line, an activation signal is sent to the renoid valve 42, and the discharge air suspension 4 is activated.
3. Blow out air to eliminate buckling from the line.

Note that it is also possible to perform this buckling detection at the same time as the differential seaming process. In this way, a separate buckling detection signal is not required, and the buckling detection device δ A lid tightening device can also be used, which can simplify the device and shorten the waiting time of the detection process. Also,
By summing up the seat/FE jF+ occurrence pocket numbers displayed on the display device 41, the condition of the lid tightening device provided in each pocket 10a of the tar left 10 can also be monitored.

Further, the unoccurred IJJ is not limited to the above-mentioned embodiment, and includes, for example, the following modifications.

■ A method for detecting buckling of a real can that has been filled with contents and the lid has been tightened, and its use as a device.

■ A method and device for detecting buckling by incorporating a proximity sensor into the pocket of the turret. With this method, buckling can be detected while the can is being transported by the turret. , the detection time can be shortened.

(2) A method and apparatus for detecting buckling by rotating a can using a rotating means other than a rotary table, such as a belt or a roll.

・■ A method and arrangement for detecting buckling using a circuit other than the above as a constituent circuit of the discriminator.

(2) A method and apparatus for detecting buckling by placing proximity switches in the part where buckling is most likely to occur and the part where buckling is least likely to occur on the same line in the can axis direction.

■ A method and device in which the input and output of each part is connected to a microcomputer via an interface, and the process is processed by a microcomputer program to detect a buckled can.

■ A method and device for detecting a buckled can by sounding an alarm or flashing an indicator light as a predetermined process when a buckled can is detected.

■ Use a device other than the air exclusion type as the removal device for buckled cans,
Also, a method and apparatus for detecting buckled cans by installing an ejector near the detection position as necessary.

■ A method and device that detects only buckling in one axial direction around the entire circumference of the can without rotating the can at the inspection position.

[Phase] A method for detecting buckled cans by rotating the can at less than 360 degrees at the inspection position, and its installation method
Usually, buckling occurs in a range of 90 degrees or more in the circumferential direction of the outer periphery of the can, so a certain effect can be obtained even if the methods described in (1) and (2) above are used.

■ A method and method for detecting buckled cans based on the difference in the outputs of three or more adjacent proximity sensors when three or more proximity sensors are installed in parallel in the axial direction (in a straight line). Device.

■ A method and equipment for detecting buckled cans in plastic cans other than metal cans, paper cans, etc.

(2) A method and apparatus for detecting buckled cans by appropriately combining the above-described embodiments and modifications.

[Effects of the Invention] As described above, according to the present invention, buckling can be detected accurately and with high precision by determining the detection of a buckling can based on the output difference between proximity sensors adjacent in the axial direction. Can be done.

[Brief explanation of the drawing]

Fig. 1 is a schematic top view of an embodiment in which the detection device is installed during the tightening process, Fig. 2 is a schematic configuration diagram of the detection device, and Fig. 3 is the circuit of the control section. FIG. 4 is a block diagram of the configuration, FIG. 4 is a waveform diagram of the control section, and FIG. 5 is a diagram for explaining an example of buckling detection other than the failure II.

Claims (3)

[Claims] (1) A plurality of proximity sensors are installed in parallel on the same line in the axial direction of the can at a position close to the can that has been transferred to the inspection position by the transfer means, and these proximity sensors are used to detect the shape of the circumferential surface of the can. A method for detecting a buckled can, comprising outputting a signal and determining whether or not the can is buckled based on a difference in signals between adjacent proximity sensors. (2) A plurality of means for transferring the can along the transfer path and a proximity sensor that outputs a signal corresponding to the circumferential shape of the can are installed on the same line in the axial direction of the can at a position close to the can on the transfer path. The present invention is characterized by comprising a group of proximity sensors arranged in parallel, and a determination section that determines whether or not the can is buckled based on the difference in signals of adjacent proximity sensors in the group of proximity sensors. Buckled can detection device. (3) A method for detecting a buckled can according to claim 2, characterized in that a plurality of proximity sensor groups are arranged in a plurality of rows with different height positions of the proximity sensors in each proximity sensor group. and its equipment.