JP2024071170A - Parts feeder - Google Patents

Abstract

To realize a parts feeder that eliminates work congestion by appropriately controlling the gap between workpieces near the tip of a linear feeder.
SOLUTION
A gap control means 31 for controlling the gap Δ between the workpieces W, W is provided in a predetermined area of the conveying path 21 along which the workpieces W are vibrated and conveyed. The gap control means 31 includes a gap detection unit 31a for detecting the gap Δ between the front workpiece W (i-1) and the rear workpiece (i) in the predetermined area through image processing, a judgment unit 31b for judging whether the gap Δ detected by the gap detection unit 31a is equal to or less than a set value, and an exclusion processing unit 31c for excluding the rear workpiece W (i) from the conveying path 21 when the judgment unit 31b judges that the gap Δ is equal to or less than the set value.
[Selected Figure] Figure 1

Description

The present invention relates to a parts feeder that enables workpieces on a conveying path to be supplied to a destination at the appropriate time.

In general, parts feeders that transport fine workpieces such as surface-mount electronic components are configured so that a bowl feeder with a spiral transport path lifts the workpiece along a track, and then a linear feeder with a straight transport path aligns the workpiece while feeding it to the destination, such as a component inspection device or component mounting device.

Of these, Patent Document 1 shows an index table as a supply destination device. Figure 9 shows a different parts feeder PF that uses such an index table as a supply destination. This parts feeder PF forms a vibration conveying system with a bowl feeder 1 and a linear feeder 2, and an index table 100 with storage sections 101 provided at a predetermined pitch on its outer periphery is connected to the tip 21a of the conveying path 21 of the linear feeder 2. The work W that reaches the tip 21a of the linear feeder 2 is taken in by the storage section 101 of the index table 100, and then the index table 100 rotates in a stepwise manner so that the next storage section 101 takes in the work W that is newly supplied from the tip 21a of the linear feeder 2.

Patent Publication 2022-59301

The timing at which this type of parts feeder PF supplies workpieces to the destination depends on the processing speed of the index table 100, which is the equipment at the destination. If the workpieces W are supplied to the end of the conveying path 21 at a faster pace than the destination, congestion of the workpieces W occurs at the end 21a of the conveying path 21, making it difficult to transfer the workpieces W smoothly. For this reason, it is necessary to eliminate the congestion of the workpieces at the end of the conveying path 21.

In the example shown in Figure 9, a vibration-free transfer section 110 is provided between the tip 21a of the linear feeder 21 and the index table 100, and a separation pin 120 is provided at this transfer section 110 so as to protrude upward from the conveying surface. When a preceding workpiece W enters the storage section 101 as shown in Figure 10(a), the separation pin 120 is protruded from the transfer section 110 to prevent a subsequent workpiece W from entering the same storage section 101 at the same time.

However, in recent years, as the workpieces have become finer, it has become easier for multiple workpieces W to enter the storage section 101 at the same time. For example, as shown in FIG. 10(b), a situation may occur in which a workpiece W following a front workpiece W enters the storage section 101 at the same time. For this reason, if the separation pin 120 rises while a rear workpiece W following a front workpiece W are simultaneously entering the storage section 101, the workpieces W cannot be separated, and the separation pin 120 will mesh with the workpiece W, causing problems such as workpiece clogging. Furthermore, introducing a mechanical element that operates like the separation pin 120 can cause malfunctions of the mechanical element, such as pin clogging due to wear or debris.

The above-mentioned Patent Document 1 does not employ such mechanical elements, but instead uses optical light blocking to detect congestion of workpieces. Specifically, as shown in Figures 7 to 9 of the document, multiple optical sensors are provided at the end of the transport path, and the positions and ranges of the sensors are devised so that not all of the sensors react simultaneously to a single workpiece, but only when the workpieces are overlapping and connected, and measures are taken to detect overlapping workpieces and remove the overlapping workpieces. For this reason, holes must be drilled in the transport path for emitting and receiving light, and the positions and ranges of the holes change if the sizes of the workpieces differ, so the structure in the document has the drawback that it cannot easily accommodate different types of workpieces.

The present invention was made with an eye on these issues, and aims to realize a new parts feeder that eliminates work congestion by appropriately controlling the gap between workpieces near the tip of the linear feeder.

To achieve this objective, the present invention takes the following measures:

In other words, the parts feeder according to the present invention is provided with a gap control means for controlling the gap between workpieces in a predetermined area of a conveying path along which the workpieces are conveyed by vibration, and the gap control means is characterized by comprising a gap detection unit that detects the gap between a front workpiece and a rear workpiece in the predetermined area through image processing, a judgment unit that judges whether the gap detected by the gap detection unit is equal to or smaller than a set value, and an exclusion processing unit that excludes the rear workpiece from the conveying path when the judgment unit judges that the gap is equal to or smaller than the set value. Here, the predetermined area can basically be set anywhere as long as it is a position where a workpiece on the conveying path can be detected.

In this way, since no mechanical elements such as separation pins are introduced, problems such as workpiece clogging do not occur, and wear and debris caused by mechanical elements can also be avoided. Also, since gaps are detected through image processing rather than optically detecting overlaps, there is no need to modify the transport path itself even if there are differences in workpiece size, and the problem can be easily and appropriately handled through software by changing settings, etc.

As a specific embodiment, the gap detected by the gap detection unit is the time from when the rear end of the front workpiece passes a predetermined position to when the front end of the rear workpiece arrives at the predetermined position, and the judgment unit judges whether the detected time is equal to or shorter than the predetermined time.

With this configuration, if the specified time is set to at least the time required for the work to be processed at the supply destination, it is possible to accurately prevent the rear work from reaching the supply destination before the processing of the front work is completed, resulting in duplication.

In another specific embodiment, the gap detected by the gap detection unit is the distance between the rear end of the front workpiece and the front end of the rear workpiece, and the judgment unit judges whether the detected distance is equal to or smaller than a predetermined distance.

Even if the gap is the same time interval, if the speed of the rear work is slower than that of the front work, the distance between the works will increase after detection, and if it is faster, the gap between the works will decrease. For this reason, by defining the required gap between works as a distance and ensuring that at least the distance traveled by the rear work while the work is being processed at the supply destination is equal to or greater than a specified distance, it is possible to accurately prevent the rear work from reaching the supply destination before the processing of the front work is completed, resulting in duplication.

When the rear workpiece is removed, it is desirable for the gap control means to perform similar gap control on the gap between the front workpiece and the new workpiece that is rear of the front workpiece.

When a workpiece is removed, the workpiece behind it no longer has a reference point in front of it. In this case, since there is no reference point, the subsequent workpiece is not allowed to pass unconditionally, but the gap for the subsequent workpiece is determined based on the workpiece in front of the removed workpiece, ensuring the effectiveness of gap control.

According to the present invention as described above, it is possible to provide a new parts feeder that eliminates work congestion by appropriately controlling the gap between workpieces near the tip of the linear feeder.

1 is a schematic front view showing a part feeder according to a first embodiment of the present invention; FIG. 2 is a schematic plan view of the parts feeder of FIG. 1 . 5A to 5C are diagrams showing a procedure for detecting a workpiece end portion from an image captured by a line camera in the embodiment; 13 is a diagram showing a time series of the relationship between the workpieces when the gap between the workpieces is defined in terms of time in the embodiment. FIG. FIG. 4 is a diagram showing a gap control flow in the embodiment. FIG. 4 is a schematic diagram showing the manner in which the workpiece is removed in the embodiment. FIG. 11 is a time-series diagram showing the relationship between the workpieces when the gap between the workpieces is defined as a distance in the second embodiment of the present invention. FIG. 4 is a diagram showing a gap control flow in the embodiment. FIG. 1 is a schematic diagram showing a conventional parts feeder. FIG.

The following describes an embodiment of the present invention with reference to the drawings.

First Embodiment
As shown in Figures 1 and 2, a parts feeder PF according to a first embodiment of the present invention includes a bowl feeder 1 and a linear feeder 2 for vibratingly transporting workpieces W in cooperation with each other, and a control device 3 for controlling these.

The bowl feeder 1 includes a bowl body 11 capable of accommodating the workpiece W, and a first driving means 12 disposed below the bowl body 11 and configured to vibrate the bowl body 11 with torsional vibration.

The bowl body 11 is a member that is roughly partially inverted cone-shaped with an open top, and a spirally ascending conveying path 13 is formed in the shape of a groove on its inner peripheral wall. When the bowl body 11 is vibrated in a torsional direction by the first driving means 12, the workpiece W is conveyed upward along the conveying path 13 toward the connection part 14 with the linear feeder 2. Therefore, the vibration of the first driving means 12 affects the amount of workpieces supplied from the bowl feeder 1 to the linear feeder 2, and the greater the amplitude and frequency of the first driving means 12, the faster the conveying speed of the workpieces W conveyed along the conveying path 13 increases, and the more pieces are supplied to the linear feeder 2 per unit time.

The linear feeder 2 has a linear transport path 21 connected to the end of the transport path 13, and a second drive means 22 that vibrates the transport path 21. The second drive means 22 vibrates the transport path 21 to transport multiple workpieces W on the transport path 21 from right to left in FIG. 1. A posture determination unit and an alignment unit (not shown) are provided midway along the transport path 21, and by passing through these, the workpieces W are aligned so that, for example, the longitudinal direction of the workpieces W is parallel to the transport direction of the workpieces W and the workpieces W do not overlap.

At the tip (terminal end) 21a of the conveying path 21 of the linear feeder 2, an index table 100 is disposed as a mechanical element that serves as the entrance to the equipment to which the workpiece W is to be supplied. The index table 100 is disk-shaped, and bottomed storage sections 101 that open radially outward and upward are provided at equal intervals on the outer periphery. For convenience, the storage sections 101 are shown linearly in FIG. 2, but in reality they are formed along the outer periphery of the disk.

This storage section 101 is moved to a position that coincides with the tip 21a of the conveying path 21 of the linear feeder 2 each time the index table 100 rotates in a stepwise manner, and the workpiece W that reaches the tip 21a of the linear feeder 2 is taken in by suction using a suction section (not shown) provided in the recess 101, and is transported in the direction of rotation.

The control device 3 is composed of a normal microcomputer unit equipped with a CPU, interface, memory, etc. (not shown), and the main program that actually controls the bowl feeder and parts feeder is stored in the memory. The CPU sequentially reads and executes the programs, and cooperates with peripheral hardware resources to control the amplitude and frequency of the bowl feeder 1 and linear feeder 2, as well as control their posture, etc.

In this case, the timing of supplying the work W to the destination index table 100 depends on the processing speed of the destination equipment (such as the rotation pitch of the index table 100), and if the work is supplied to the tip 21a of the conveying path 21 at a faster pitch than the destination, a congestion of work W occurs on the conveying path 21, making it difficult to smoothly transfer the work W. Also, if the work W is supplied at a slower pitch than the destination, the index table 100 will suffer from a shortage of work.

Therefore, the first drive means 12 and the second drive means 22 are set with a frequency and amplitude that are theoretically calculated to move the multiple workpieces W, W at an appropriate speed on the conveying path 21 of the linear feeder 2. However, if each workpiece W can be approximated as a rectangular parallelepiped, for example, and the surface that contacts the conveying path 21 is not the original surface, or if there is an original surface that contacts the workpieces W, W but there is an individual difference between them, then the actual speed of the workpieces W will vary, and the spacing between the workpieces W, W cannot be controlled to be equal.

As a result, as described in the Background Art and Issues section, the work intervals become narrower than the work processing timing of the index table 100, which is the supply destination, and a situation may occur in which multiple workpieces W enter the storage section 101 of the index table 100. When the index table 100 stores a workpiece W in the storage section 101, it is controlled to rotate a predetermined angle and position a new empty storage section 101 in a position that coincides with the tip 21a of the conveying path 21 of the linear feeder 2. In order to prevent the workpieces W from overlapping in the storage section 101, it is ideal to leave a gap large enough that the rear workpiece W does not reach the tip 21a of the linear feeder 2 until the next empty storage section 101 is connected to the tip 21a of the conveying path 21 of the linear feeder 2.

However, leaving such a gap would actually result in a shortage of work on the index table 100 side. Therefore, here, after the work W is stored in the storage section 101, the index table 100 begins to rotate, and after rotating to a position where the storage section 101 is no longer visible from the linear feeder 2 as shown in Figure 2 (2-2), even if the work W is present at the tip 21a of the linear feeder 2, it will simply slide against the outer circumferential surface 102 of the index table 100. For this reason, if this state is permissible, it is acceptable for the work W to reach the tip 21a of the linear feeder 2 at this point.

Therefore, the gap between the workpieces W, W when they are circulated toward the tip in this embodiment is determined on the condition that the next workpiece W does not reach the tip 21a until the previous workpiece W is stored in the storage section 101 and the index table 100 rotates so that the storage section 101 is no longer visible from the tip 21a of the linear feeder 2 (it is no longer continuous with the tip 21a of the linear feeder 2), and the necessary gap between the workpieces W, W is specified.

To this end, in this embodiment, a gap control means 31 is provided as part of the control device 3. This gap control means 31 is provided with a gap detection unit 31a that controls the gap between the workpieces W, W in a predetermined area (near the exit of the conveying path 21 of the linear feeder 2) just before the tip 21a of the conveying path 21 of the linear feeder 2 that vibrates and conveys the workpieces W, and is configured to detect the gap Δ between the workpieces W, W using this gap detection unit 31a, determine whether the gap Δ is equal to or smaller than a predetermined gap set in advance using a judgment unit 31b, and output an exclusion signal from an exclusion processing unit 31c when the gap Δ is equal to or smaller than the set value, thereby controlling the thinning out of the workpieces W.

The preset specified gap is an interval that ensures that the succeeding work W does not reach the tip 21a of the conveying path 21 of the linear feeder 2 until the work W is processed at the supply destination, and in this embodiment, until the work W is processed is defined as until the index table 100 takes the work W into the storage section 101 and rotates to a position where the storage section 101 is no longer continuous with the tip 21a of the linear feeder 2. Of course, this specification can be changed to suit the purpose and use.

The gap detection unit 31a captures a signal from a line camera 41, an imaging element arranged in a specified area of the transport path 21, and processes the image to detect the gap Δ from the rear end of the front workpiece W[i-1] to the front end of the rear workpiece W[i].

Specifically, the line camera 41 is provided above an imaging position (scan line) P1 set on the conveying path 21 of the linear feeder 2. The line camera 41 has multiple highly sensitive imaging elements (not shown) arranged in a row perpendicular to the conveying direction of the workpiece W (extension direction of the conveying path 21 of the linear feeder 2), and captures an image of the workpiece W being conveyed on the conveying path 21. The imaging range (imaging area) of the line camera 41 is set to a range that captures an image of a portion of the workpiece W in the conveying direction of the workpiece W, and a range that captures an image of the entire workpiece W in a direction perpendicular to the conveying direction of the workpiece W.

The image data acquired by the line camera 41 is obtained by spot-capturing images using multiple imaging elements arranged in a mesh pattern, and therefore has fewer pixels and a smaller amount of data than an area camera whose imaging range covers the entire workpiece W. The line camera 41 operates to continuously capture images of the workpiece W at regular intervals, and transfers the acquired images to the control device 3.

When the line camera 41 scans at a predetermined interval (FIG. 3(a)), the image data is sent to the control device 3 immediately. The control device 3 immediately performs binarization processing on the captured images, and then sequentially combines the images to generate a workpiece composite image (FIG. 3(b)). The composite image displays the part where the workpiece W appears and the part where something other than the workpiece W (specifically, the conveying path 21 of the linear feeder 2) appears. The workpiece W and the conveying path 21 are preset to have different color attributes such as hue, brightness, and saturation. For example, if the workpiece W has electrodes on both ends of the ceramic body, the entire workpiece W will be displayed in a color close to white, whereas if the conveying path 21 is composed of a low-brightness black or the like, the image of the workpiece W can be distinguished by the color attributes.

The gap control means 31 performs gap control using the captured image of the workpiece W.

The gap detection unit 31a detects rising edges at the front end and falling edges at the rear end by processing the captured image of the workpiece W, and generates an on/off signal (Figure 3(c)).

Figure 4 shows waveforms of the on/off signals of multiple workpieces W arranged in chronological order, with the first workpiece being numbered 0, the on time of the i-th workpiece being t-on[i], and the off time from the rear end of the i-th workpiece to the front end of the i+1th workpiece being t-off[i], with i=0 to i=3 displayed.

The judgment unit 31b judges whether there is a predetermined gap between the front workpiece W and the rear workpiece W. Here, the gap Δ to be secured between at least the workpieces W, W is defined as the time from when the rear end of the front workpiece W passes the scan line P1 until the front end of the rear workpiece W arrives at the scan line P1, and is preset as a set value T-th (e.g., 10 ms).

Then, it is determined whether the detected gap (time gap) is smaller than the set value T-th. Figure 5 shows the decision flow. For example, when workpiece (No. 1) passes the scan line following workpiece (No. 0) (step S1), it is determined whether t-off[0] is smaller than the set value T-th (step S2). The initial value of β is 0. If it is no, there is no need to thin out the works, so in step S3, workpiece (No. 1) is allowed to pass, in step S4 β is maintained, i is incremented in step S5, and the process returns to step S1. Once workpiece (No. 1) has passed, the next workpiece (No. 2) can consider the gap between it and the workpiece (No. 1) that has passed.

On the other hand, if the answer is yes in step S2, the exclusion processing unit 31c performs exclusion processing on the work (No. 1) (step S6).

The workpiece removal unit 5 in Figures 1 and 2 is positioned at a removal position P2 that is set downstream in the transport direction from the imaging position (scan line) P1, and has an air injection nozzle 50 that injects compressed air toward the workpiece W. The workpiece removal unit 5 injects compressed air from the air injection nozzle 50 when the workpiece W determined to be removed is transported to the removal position P2, and removes the workpiece W from the transport path 21. As a result, the workpiece W (No. 1) on the transport path 21 is removed from the transport path as shown in Figure 6.

After the work W (No. 1) is removed, the work (No. 2) arrives. Even here, there may not be enough space (time) between the leading work (No. 0) and the work (No. 2), and in that case, it is necessary to continue removing the work (No. 2). Therefore, in step S7, β is updated to the value obtained by adding t-off[0] + t-on[1] in FIG. 4, i is incremented (step S5), and the process returns to step S1. Then, after the work (No. 2) passes the scan line next (step S1), it is determined in step S2 whether t-off[1] + t-off[0] + t-on[1] is smaller than the set value T-th. This is the gap from the work (No. 0) to the work (No. 2). If it is no, the work (No. 2) is allowed to pass. If the work (No. 2) passes, the gap between the work (No. 2) that has passed and the next work (No. 3) is the problem, so β is reset to 0 (step S4), i is incremented (step S5), and the process returns to step S1. On the other hand, if step S2 determines that the number is small, then the work (number 2) is subjected to an exclusion process (step S6).

After work (No. 2) is removed, work (No. 3) arrives. Here too, there may not be enough space (time) between the first work (No. 0) and work (No. 3), so β is further updated (step S7), i is incremented (step S5), and the process returns to step S1. There is a limit to how many times the loop going from step S2 to S6 is followed, and eventually step S2 will determine "no," and the accumulated β will be reset to 0.

As described above, the parts feeder PF of this embodiment is provided with a gap control means 31 that controls the gap Δ between the workpieces W, W in a predetermined area of the conveying path 21 of the linear feeder 2 that vibrates and conveys the workpieces W. The gap control means 31 is equipped with a gap detection unit 31a that detects the gap Δ between the front workpiece W (i-1) and the rear workpiece (i) in the predetermined area through image processing, a judgment unit 31b that judges whether the gap Δ detected by the gap detection unit 31a is equal to or less than a set value, and an exclusion processing unit 31c that excludes the rear workpiece W (i) from the conveying path 21 when the judgment unit 31b judges that the gap Δ is equal to or less than the set value.

In this way, there is no need to introduce mechanical elements such as separation pins to eliminate congestion of workpieces W near the end of the transport path 21, so there is no trouble such as workpiece clogging, and it is also possible to avoid wear and debris caused by mechanical elements. Also, since gaps are detected through image processing rather than optically detecting overlapping workpieces W, there is no need to modify the transport path 21 itself even if there are differences in the sizes of the workpieces W, and differences in the sizes of the workpieces W can be easily and appropriately handled using software by changing settings, etc.

In particular, in this embodiment, the gap Δ detected by the gap detection unit 31a is the time from when the rear end of the front workpiece W(i-1) passes a predetermined position to when the front end of the rear workpiece W(i) arrives at the predetermined position, and the judgment unit 31b judges whether the detected time is equal to or shorter than the predetermined time.

With this configuration, if the set value is set to at least the time required for the work W to be processed at the destination index table 100, it is possible to accurately prevent the later work (i) from reaching the destination before the processing of the earlier work (i-1) is completed, resulting in duplication.

In addition, when the rear workpiece W(i) is removed, the gap control means 31 also performs similar gap control on the gap Δ between the front workpiece W(i-1) and the new rear workpiece W(i+1) relative to the front workpiece W(i-1).

When a workpiece W(i) is removed, the workpiece W(i+1) behind it no longer has a workpiece W(i) in front of it to serve as a reference. In this case, since there is no reference, the workpiece W(i+1) is not allowed to pass unconditionally, but the gap is judged based on the workpiece W(i-1) in front of the removed workpiece W(i), ensuring the effectiveness of gap control.

Second Embodiment
In this embodiment, the gap between the workpieces is defined by distance, and the gap detection unit 31a detects the inter-workpiece distance between the rear end of the front workpiece W[n-1] and the front end of the rear workpiece W[n].

Figure 7 shows the on/off signals of multiple workpieces W arranged in chronological order, with the first workpiece being numbered 0, the on time of the nth workpiece being t-on[n], and the off time from the rear end of the nth workpiece to the front end of the n+1th workpiece being t-off[n], with n=0 to n=3 being displayed.

The judgment unit 31b judges whether there is a predetermined gap between the front workpiece W[n-1] and the rear workpiece W[n]. Here, the gap Δ to be secured between at least the workpieces W, W is defined as the distance between the front workpiece W and the rear workpiece W.

First, the speed of each workpiece W is calculated from the detected waveform. If the size of the workpiece W is Lwork, the speeds of the workpiece (No. 0) and the workpiece (No. 1) are as follows:
Vwork[0] = Lwork÷t on[0]
Vwork[1] = Lwork÷t on[1]
It is.

Next, the gap time between each workpiece W is converted into the distance between each workpiece.
D[0]...Distance between workpiece (no. 0) and workpiece (no. 1).
D[1]…Distance between workpiece (no. 1) and workpiece (no. 2).
t-off[0]...The time from when the workpiece (number 0) passes until the head of the workpiece (number 1) enters.
t-off[1]…The time from when the workpiece (number 1) passes until the head of the workpiece (number 2) enters.
Vwork[1]...speed of work (No. 1) Vwork[2]...speed of work (No. 2) By multiplying the gap time between workpieces by the speed of the subsequent workpiece, the distance between the workpieces can be approximately calculated as shown below.
D[0] = t-off[0] × Vwork[1]
D[1]＝t-off[1]×Vwork[2]

Then, it is determined whether the detected gap is smaller than the set value D-th, which is a predetermined gap. Figure 8 shows the determination flow. For example, when workpiece (No. 1) passes through scan line P1 following workpiece (No. 0) (step S101), it is determined whether D[0] is smaller than the set value D-th (step S2). The initial value of α is 0. If no, there is no need to thin out the workpieces W, so in step S103, the workpiece (No. 1) is passed, and in step S104, α is set to 0 again, and in step S105, n is incremented and the process returns to step S101. Once workpiece (No. 1) has passed, the next workpiece (No. 2) can consider the gap between it and the workpiece (No. 1) that has passed.

On the other hand, if the answer is yes in step S102, the exclusion processing unit 31c performs exclusion processing on the work (No. 1) (step S106).

As mentioned above, the workpiece removal unit 5 in Figures 1 and 2 is positioned at a removal position P2 set downstream in the transport direction from the imaging position (scan line) P1, and has an air injection nozzle 50 that injects compressed air toward the workpiece W. When a workpiece for which an exclusion command has been issued is transported to the removal position P2, the workpiece removal unit 5 injects compressed air from the air injection nozzle 50, and removes the workpiece 3 from the transport path 10. As a result, the workpiece (No. 1) on the transport path is removed from the transport path as shown in Figure 6.

After the work (No. 1) is removed, the work (No. 2) arrives. Even here, there may not be enough space (distance) between the leading work (No. 0) and the work (No. 2), and in that case, it is necessary to continue removing the work (No. 2). Therefore, α is updated to the value obtained by adding D[0]+Lwork in FIG. 4 (step S107), n is incremented (step S105), and the process returns to step S101. Then, after the work (No. 2) passes through the scan line P1 (step S101), it is determined in step S102 whether D[n]+D[0]+Lwork is smaller than the set value D-th. This is the distance from the work (No. 0) to the work (No. 2). If no, the work (No. 2) is allowed to pass in step S103. Once the workpiece (No. 2) has passed, the next workpiece (No. 3) only needs to consider the gap between it and the workpiece (No. 2) that has passed, so α is reset to 0 (step S104), n is incremented (step S105), and the process returns to step S1. On the other hand, if the answer is yes in step S102, the workpiece (No. 2) is subjected to an exclusion process (step S106).

After work (No. 2) is removed, work (No. 3) arrives. Here too, there may not be a sufficient distance between the leading work (No. 0) and work (No. 2), so α is further updated (step S107), n is incremented (step S105), and the process returns to step S101, repeating the same procedure as above. There is a limited number of loops going from step S102 to S106, and eventually step S102 will be judged as no, and the accumulated α will be reset to 0.

In the above embodiment, the gap detected by the gap detection unit 31a was defined as the time when the rear workpiece W[i] arrives after the front workpiece W[i-1] has passed, but in this case, even if the gap is the same time interval, if the speed of the rear workpiece W[i] is slower than the front workpiece W[i-1], the distance between the works will increase after detection, and if it is faster, the gap between the works will decrease. For this reason, if there is a large variation in the speed of the workpieces, it may not be possible to properly process the gap using only the gap time.

In contrast, in this embodiment, the gap detected by the gap detection unit 31a is defined as the inter-work distance between the rear end of the front work W[n-1] and the front end of the rear work W[n], and the judgment unit 31b judges whether the detected distance is equal to or less than a set value. By making sure that the distance traveled by the rear work W[n] while the front work W[n-1] is being processed at the supply destination is at least a predetermined distance, it is possible to reliably prevent the rear work [n] from reaching the supply destination before processing of the front work [n-1] is completed, resulting in duplication.

Two embodiments of the present invention have been described above, but the specific configuration of each part is not limited to the above-mentioned embodiments.

For example, the gap detection unit may be provided on the conveying path of a linear feeder, or on the conveying path of a bowl feeder.

In addition, while the above embodiment has been described as a parts feeder, when viewed as a method for controlling the gap between workpieces in a specified area of a conveying path along which the workpieces are vibrated and conveyed, if the gap control method for a parts feeder includes a gap detection step for detecting the gap between a front workpiece and a rear workpiece in the specified area through image processing, a determination step for determining whether the gap detected in the gap detection step is equal to or less than a set value, and a workpiece removal processing step for removing the rear workpiece from the conveying path when it is determined in the determination step that the gap is equal to or less than the set value, the same effects as those of the above embodiment can be achieved regardless of the assembly structure of the functional elements of the parts feeder.

In addition, in the above embodiment, the rear workpiece is removed when the judgment unit judges that the value is equal to or greater than the set value, but a workpiece posture reversal unit may be operated to reverse the posture of the rear workpiece on the transport path when the judgment unit judges that the value is equal to or greater than the set value. In this case, the specified area may be located at least on the transport path, and may be provided upstream of the workpiece reversal unit.

When you want to flip a workpiece that is upside down on the transport path, if the gap between the workpieces is small, the adjacent workpiece will be caught in the gap when flipping the workpiece. In contrast, if you configure it as described above, the workpiece can be flipped only when there is a sufficient gap between the workpieces.

Other configurations may also be modified in various ways without departing from the spirit of the present invention.

PF: Parts feeder W: Work
T-th: Set value (time)
D-th: Setting value (distance)
21: conveying path 31: gap control means 31a: gap detection section 31b: determination section 31c: exclusion processing section

Claims (4)

A gap control means for controlling the gap between the workpieces is provided in a predetermined area of the conveying path along which the workpieces are vibrated and conveyed,
The gap control means
A gap detection unit that detects a gap between a front workpiece and a rear workpiece in the predetermined area through image processing;
a determination unit that determines whether the gap detected by the gap detection unit is equal to or smaller than a set value;
an exclusion processing unit that excludes the rear work from the conveying path when the determination unit determines that the value is equal to or less than a set value;
A parts feeder comprising: The gap detected by the gap detection unit is a time from when the rear end of the front workpiece passes a predetermined position to when the front end of the rear workpiece arrives at the predetermined position,
2. The parts feeder according to claim 1, wherein the determining unit determines whether the detected time is equal to or shorter than a predetermined time. The gap detected by the gap detection unit is a work-to-work distance between a rear end of a front work and a front end of a rear work,
The determination unit determines whether the detected distance is equal to or less than a predetermined distance. The parts feeder according to claim 2 or 3, wherein the gap control means, when the rear workpiece is removed, performs similar gap control on the gap between the front workpiece and a new workpiece that is rear of the front workpiece.

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