JP7176746B2 - Welding point monitoring device - Google Patents

Description

The present invention relates to a welding point monitoring device that counts the number of welding points in spot welding work or other welding work and notifies a worker that the number of welding points that have been completed has reached the required number.

Spot welding is a technique in which at least two sheets to be welded are placed on top of each other, sandwiched between a pair of electrodes, and energized between the electrodes while applying pressure to the sheets to weld the sheets together. be. In performing spot welding work, excess or deficiency of welding points leads to fatal defects. Conventionally, there is no dedicated machine for simply performing such management.

For this reason, currently, the welding operator confirms the drawing, checks the designated processing points in advance, performs the required number of welds at the required points, and checks for excess or deficiency in the number of welding points in the inspection process. Checking prevents the outflow of products with excessive or insufficient welding points. Human error may occur in both checks, and the problem has not been eradicated.

In a spot welder, the welding point is sandwiched between electrodes, and from that state pressure is applied to apply a welding current. For this reason, the electrode receives the heat of the welded portion, and the state of the electrode such as wear, deformation, or adhesion of plating material deteriorates with each hit point. In order to warn of such deterioration, recent spot welders are equipped with a function of issuing an alarm each time the number of welding points reaches a certain number. This function cannot be used to check the excess or deficiency of welding points in the work of welding a plurality of parts with different numbers of welding points in one product to be welded.

In spot welders that do not have a function to count welding points and that do not have means for outputting welding completion signals to the outside, welding points are counted in conjunction with the operation of the welding start switch by the operator. A counting method has also been proposed. However, in welding work, the operation of opening the switch before energization occurs frequently in correcting the position of the welding point, checking the pressure, polishing the electrode, and the like. Therefore, there is a problem that the starting switch and the actual number of welding do not match, and the welding points cannot be counted accurately.

On the other hand, some measuring instruments for monitoring welding current have a counting function. This type of measuring instrument is primarily intended for accurate current measurement for a specified welding current. Therefore, it is necessary to arrange a measuring instrument such as a toroidal coil near the machining point electrode. Depending on the shape of the product to be welded, it may not be possible to place the measuring instrument at an appropriate location, making measurement difficult. Also, since the main purpose is to measure the welding current accurately, it is necessary to change the toroidal coil depending on the welding conditions. difficult to use for Furthermore, since the measuring instrument is provided with only one signal input terminal from the measuring instrument, it is necessary to use the measuring instrument to count welding points in welding work that requires multiple processing heads. Replacing work is required, which is inconvenient and work efficiency is poor.

For example, Japanese Unexamined Patent Application Publications Nos. 2003-100000, 2003-100000, and 2003-300000 disclose welding devices having a function of counting welding points. The welding devices described in these documents have a configuration in which a dedicated welding point counting mechanism is incorporated in advance in the welding device.

Japanese Utility Model Laid-Open No. 63-29682 JP-A-63-49377 JP-A-63-49378

As described above, conventionally, as a mechanism for counting welding points in spot welding, a dedicated welding point counting mechanism incorporated in the spot welding apparatus and a function provided in the spot welding apparatus are used to count the welding points. A counting mechanism and the like are known. However, the current situation is that there is no effective means for counting welding points for old spot welders, simple manual welders, and stud welders that do not have an output function such as a welding completion signal to the outside. is. In addition, no proposal has been made in the past for a highly portable welding spot monitoring device (shot counter) that can be installed at a required location and can easily monitor the number of welding spots as needed.

In particular, in recent years, for purposes such as functional expansion and cost reduction, parts to be welded have become more complicated, and spot welding work has also diversified. For example, there is a work of welding a plurality of parts to the same product at different welding points, a work of welding the same product using different types of spot welders (a plurality of processing heads), and the like. In addition, there are sites where products change frequently, and the number of welding points and welding machines must be changed frequently. An excess or deficiency of welding points causes a fatal defect in product quality, but no general-purpose device capable of easily counting welding points in such spot welding work has been proposed in the past.

Furthermore, in a welding point counting mechanism incorporated in a conventional spot welder, when a plurality of workers work in close proximity, a worker who hears an alarm sound emitted by the counting mechanism In some cases, an error may occur in which the worker misidentifies the alarm sound for the work as the alarm sound for his own work, and advances the work to the next process. In addition, every time a work completion alarm is issued, the operator must move to the installation location of the welding device and perform a predetermined operation to reset the alarm to stop the alarm sound, which is inconvenient. is.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a highly portable and versatile welding point monitoring device capable of easily counting the number of welding points. In other words, when the type and number of spot welders used are different, when welding multiple parts with different numbers of welding points, old-type welders that do not have an output function such as a welding completion signal to the outside or simple models When using a spot welder or stud welder, it can be easily brought to the required place, alarm generation, reset operation, etc. can be performed at the operator's hand, and the number of welding points can be easily counted. To provide a welding point monitoring device excellent in portability and versatility.

In order to solve the above-mentioned problems, the welding point monitoring device of the present invention includes a portable main box in which a control unit for monitoring welding points is incorporated, and a sensor for detecting that spot welding has been performed for each welding point. and a remote box that is wired or wirelessly connected to the control unit. The control unit includes a counter that counts the number of welding points (number of welding processes) detected by the sensor, a setting section that presets the required number of welding points, and when the count value of the counter reaches the required number of welding points set in the setting section. and a reporting unit for outputting a report. The remote box has a remote reset switch operated to give a reset command to the control unit to stop reporting by the reporting section.

Here, it is desirable that the notification unit can output the notification in a visually and audibly recognizable form.

Also, the main box is preferably equipped with a magnet for magnetically attaching the main box to another member so that the device can be easily installed in a suitable location. In this case, the operation panel is rotated about an axis perpendicular to the outer surface of the main box so that the vertical direction of the operation panel can be adjusted according to the installation posture of the main box. It is desirable to be able to connect in a viable manner and to be able to lock in a predetermined rotational angular position about the axis.

In addition, the remote box also has a remote reporting unit that outputs reports in conjunction with the reporting unit of the control unit, and when the remote reset switch is operated, the reporting of the remote reporting unit stops. is desirable.

Furthermore, it is desirable that the remote box also has a magnet for magnetically attaching the remote box to another member.

By using the welding point monitoring device of the present invention, it is possible to sense the required number of weldings on a product and notify the worker of the end of processing by warning sound and lighting or blinking of light. At the work site, the welding work can be performed with a double check system based on the recognition of the worker and the monitoring by this device.

In particular, when the number of production lots is large, there is a high possibility that human errors such as forgetting to weld or overlooking inspection will occur. By using this device, the welding work can be monitored in real time, so regardless of the size of the production lot, it is possible to prevent the number of welding points from being excessive or insufficient, and to prevent the outflow of defective products to the next process.

In addition, since the remote box is used, it is convenient because it is possible to perform remote control such as canceling the report. In addition, the main box and remote box have magnets so that they can be installed without the use of tools, making it easy to find a place to install this device even at sites where products change frequently, reducing stress associated with work. , it is possible to suppress a decrease in work efficiency.

Next, the welding point monitoring device of the present invention has a main box and a control unit incorporated in the main box, the control unit
an input operation unit;
a plurality of ports capable of inputting sensing signals of sensors attached to the spot welder to sense that spot welding has been performed;
a monitoring mode setting unit for setting the welding point monitoring mode to either single port mode or multiport mode;
a port selection/switching unit that selects one of the ports as a monitoring port in the single-port mode, and sequentially switches the port to be used as the monitoring port in the multi-port mode according to a predetermined port order;
In single port mode, multiple required welding points (or required number of welding points corresponding to the number of ports) are set according to a predetermined setting order for monitoring ports based on input from the input operation unit. and in the multi-port mode, a number setting unit capable of setting the required number of welding points for each of the ports based on the input from the input operation unit;
A counter that counts welding points based on the detection signal of the sensor input to the monitoring port, and when the number of welding points counted by the counter reaches the required number of welding points set for the monitoring port, a welding completion notification is sent. a reporting unit to output;
a reset switch operated to stop the output of the notification by the notification unit and reset the count value of the counter to zero,
In the single port mode of the port selection/switching section, each time a reset operation is performed, the required number of welding points set for the monitoring port is switched according to the setting order. The monitoring port is switched according to the port order.

With this configuration, at the welding work site, versatility to monitor welding work that requires multiple specified numbers of points for one product, welding work that uses multiple types of processing heads for one product, and other welding work It is possible to provide a welding spot monitoring device with high Therefore, it is possible to reduce the occurrence of human error due to over- or under-welding even for individual parts in a product that uses a plurality of welded parts.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram showing a welding point monitoring device according to an embodiment of the present invention, a front view and a side view of its main box, an external view of its remote box, and an external view of its sensor; It is a functional block diagram which shows the control system of a welding spot monitoring apparatus. 4 is a signal waveform diagram showing signal processing of an input signal processing section; FIG. 4 is a flow chart showing the monitoring operation of the welding point monitoring device; It is explanatory drawing which shows the welding process example of the welding work which welds several members to one product. FIG. 5 is an explanatory diagram showing an example of welding stud bolt processing in which a plurality of processing heads for one product are used for welding; FIG. 4 is an explanatory view showing sensor mounting positions when a known stationary spot welder is monitored using a welding point monitoring device; FIG. 4 is an explanatory diagram showing an example of sensor mounting positions when a known stud bolt welder is monitored using a welding point monitoring device;

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1(a) is an explanatory diagram showing a welding spot monitoring device (shot counter) according to an embodiment of the present invention, FIG. 1(b) is a front view showing its main box, and FIG. 1(c). is its side view.

Welding point monitoring device SC is mainly composed of three parts: main box MB, remote box RB and sensor 24 (24a to 24d). The remote box RB can be arranged at a position distant from the main box MB, and communicates with the main box MB by wire or wirelessly. The sensor 24 is attached, for example, to a predetermined portion of a known welding device (see FIGS. 7 and 8). From the sensor 24, a sensing signal used for counting welding points by a welding device (not shown) is input to the main box MB. A plurality of sensors 24 can be connected to the main box MB, and in this example, up to four sensors 24a to 24d (see FIG. 2) can be connected as described later. The number of connected devices is not limited to four. Also, the sensor 24 is connected to the main box MB by wire or wirelessly.

As shown in FIGS. 1B and 1C, the main box MB includes a rectangular parallelepiped frame 10 as a whole and a rectangular operation panel 11 attached to the front surface of the frame 10 . The operation panel 11 includes a count value display section 1 consisting of a 7-segment display, a lot value display section 2 consisting of a 7-segment display for displaying a lot value (LOT value), an input signal processing selection button 3, and a reset switch. 4, port indicator light 9, power switch SW, lot set button 6 for setting lot value, shot set button 7 used for setting the required number of welding points, port set button 8 for selecting port 24 for sensor input, An IN/OUT lamp 8S for displaying a monitoring mode, a volume control knob 12 for a notification sound, and the like are arranged. When the port set button 8 is long pressed, it functions as a toggle button and can switch between the monitoring mode IN/OUT. Inside the frame 10 is incorporated a control unit IB which is mainly composed of a computer.

Fixings 5 made of magnets are attached to the four corners of the outer bottom surface of the frame 10 . The magnetic force of the magnet-type fixture 5 allows the main box MB to be easily attached to a place with good workability without interfering with work around the processing machine (welding device). For example, the main box MB can be installed at a side position 78 such as a frame made of a magnetic material in a stationary welder shown in FIG.

In addition, the vertical orientation of the operation panel 11 can be adjusted according to the installation posture of the main box MB. Therefore, the operation panel 11 is wired on the front surface of the frame 10 of the main box MB so that it can be rotated about an axis perpendicular to the front surface. Further, the operation panel 11 can be fixed at a predetermined rotational angular position about the axis by a panel fixture 11a. In this example, the panel fixtures 11a such as screws attached to the four corners of the front frame of the main box MB are used to fix angular positions every 90°, for example, clockwise 90°, 180°, left A panel with a square outline is adopted as the operation panel 11 so that it can be fixed at a position of 90°.

The count value display unit 1 arranged on the operation panel 11 inputs to four ports 25a to 25d (see FIG. 2) indicated by port lamps 9a to 9d consisting of four LEDs constituting the port indicator lamp 9. It is possible to display the count value of welding points based on each sensor signal and the required number of welding points (set values a to d) set for each port 25a to 25d. The port lamps 9a to 9d corresponding to the set ports 25a to 25d are lit, and the port lamps 9a corresponding to the ports 25a to 25d connected to the sensors 24a to 24d used for monitoring the number of welding points. 9d blinks or the color tone of the lighting color changes, making it visible and identifiable.

The lot value display unit 2 can display a lot value (Ls), which is the number of products to be manufactured, and a count value (L) of the number of lots. The input signal processing selection button 3 can set the dead time of the input signal (see FIG. 3). A reset switch 4 is a reset switch for stopping reporting.

As shown in FIG. 1(a), the remote box RB has an elongated rectangular parallelepiped case, a remote reset switch 16 is arranged on the front of the case, and a plurality of switches, for example two magnets, are provided on the back of the case. are arranged. As in the case of the main box MB, the magnetic force of the magnet-type fixture 15 allows the remote box RB to be easily attached to a place with good workability without interfering with work around the processing machine. For example, the remote box RB can be installed at a position 77 in front of the frame of the stationary welder shown in FIG. 7 with one touch without using a fixing tool. Also, the remote reset switch 16 is a reset switch for stopping reporting, and functions in the same manner as the reset switch 4 on the side of the main box MB. The remote box RB is connected to the control unit IB incorporated in the main box MB by, for example, a distribution cable c-2. The connection between the remote box RB and the control unit IB of the main box MB may be wired or wireless.

As shown in FIG. 1(a), the sensor 24 includes a magnetic sensing section 17 and an indicator lamp 18 indicating that the sensor 24 is selected and in operation. The sensor 24 is connected to the control unit IB of the main box MB by a distribution cable c-1. The magnetic sensing part 17 is arranged at a place where it can capture the rotating magnetic field of the machining current to be monitored. Indicator light 18 indicates that sensor 24 is selected and being monitored. For example, the indicator light 18 of the selected sensor 24 lights up, and the indicator light 18 of the sensor 24 being monitored blinks or can be visually recognized and identified by color tone.

Next, FIG. 2 is a functional block diagram of the control system of the welding spot monitor SC. In this example, four sensors 24a-24d are connected to the control unit IB of the main box MB. The sensors 24a to 24d are attached to locations where the rotating magnetic field generated by the current of each processing machine (not shown) of the spot welding apparatus can be detected. It is desirable that the mounting position is a place that does not interfere with work and is not subject to external forces such as vibrations as much as possible. For example, as shown in FIG. 7, in a spot welding device 70, sensors 24a to 24d may be fixed at positions 74 on the lower surface of the busbar.

Each sensor 24a-24d senses a magnetic field generated by the flow of electric current required for spot welding. Sensing signals from the sensors 24a to 24d are input to the input signal processing section 25 of the control unit IB via four input/output ports 25a to 25d arranged in the control unit IB of the main box MB. The input signal processing unit 25 performs signal processing on the sensed signal to generate a pulse signal representing the welding point. The counter 26a counts up the count value T of the number of welding points based on the pulse signal. The count value T is displayed on the count value display section 1 arranged on the display section 22 of the operation panel 11 . The counter 26b counts the number of product lots. The count value L is displayed on the lot value display section 2 arranged on the display section 22 of the operation panel 11 .

The count value setting unit 27 includes a shot set button 7 for welding point setting, a port set button 8 for port selection, and a count value increase switch. , and a count value decrement switch, it is possible to set the set value of the required number of welding points in advance. In this example, four types of set values a to d can be set corresponding to the four ports 25a to 25d.

In the comparison unit 28, one of the setting values a to d of the required number of welding points set in the count value setting unit 27 is selected as the setting value S, and the selected setting value S is compared with the count value T. be done. When the count value T reaches the set value S, the notification unit 29 outputs a welding completion notification to the effect that welding of the required number of welding points has been completed. It is desirable to notify the operator of the completion of welding in a form that can be visually and audibly recognized. In this example, for example, it is notified by a buzzer sound and light emission. The remote box RB connected to the control unit IB also has a similar built-in remote notification unit 29R for outputting a welding completion notification, and the welding completion notification can be visually and audibly recognized from the remote box RB as well. emitted in the form

The reset switch 4 arranged on the operation panel 11 is enabled when the notification of completion of welding is output. When the reset switch 4 is pressed while the welding completion notification is being output, the output of the welding completion notification by the notification unit 29 and the remote notification unit 29R is stopped, and a reset operation is performed to return the count value T of the counter 26a to zero. . Similarly, by pressing the remote reset switch 16 arranged on the remote box RB, the output of the notification of completion of welding is stopped, and the count value T of the counter 26a is reset to zero. In this manner, the notification unit 29 and the remote notification unit 29R issue a welding completion notification in the form of a buzzer or the like when the number of welding points T reaches the set value S, thereby informing the operator of the completion of the welding work. After the worker recognizes the completion of welding, the worker himself presses the reset switch 4 or the remote reset switch 16, thereby stopping the output of the welding completion notification such as buzzer sound and warning light emission, and the count value of the counter 26a becomes zero. reset.

Similarly, the count value setting unit 27 includes a lot set button 6 for setting the number of lots arranged on the operation panel unit 23 (input operation unit) of the operation panel 11, a count value increase switch and a count value decrease switch. can be used to set the set value Ls of the required product lot number in advance. The comparison unit 28 compares the set value Ls of the number of lots set in the count value setting unit 27 with the count value L. FIG. When the count value L reaches the set value Ls, the reporting unit 29 outputs a work completion report to the effect that the welding work for the required lot number of products has been completed. It is desirable to notify the worker of the completion of the work in a visually and audibly recognizable form. In this example, for example, it is notified by a buzzer sound and light emission. The remote notification section 29R of the remote box RB connected to the control unit IB also issues a work completion notification in a visually and audibly recognizable form. When the reset switch 4 is pressed, the notification output of work completion by the notification unit 29 and the remote notification unit 29R is stopped, and a reset operation is performed in which the count value L of the counter 26b returns to zero. Similarly, by pressing the remote reset switch 16 arranged on the remote box RB, the output of the work completion report is stopped and the count value L of the counter 26b is reset to zero.

Note that the monitor mode setting unit 28A sets the operation mode IN/OUT. Selection of the operation mode IN/OUT is performed by pressing and holding the port set button 8 on the operation panel 11 to toggle the selection of the operation mode IN/OUT by the monitoring mode setting section 28A. Also, AC or DC power from the outside can be used as the power source of the control unit IB of this example, but a battery can be mounted as the power source to improve portability.

FIG. 3 is a signal waveform diagram for explaining the signal processing operation of the input signal processing section 25 described above. There are various types of known welding devices to be monitored by the welding point monitoring device SC. For example, waveforms of sensing signals of the sensors 24a to 24d obtained from an AC welder, a capacitor welder, and a welder performing two-time current welding of known spot welding devices are shown in FIGS. (d). In these figures, the vertical axis represents the sensing level and the horizontal axis represents the passage of time. Also, FIG. 3(a) shows the input signal setting time in the input signal processing section 25. As shown in FIG. As for the input signal setting time, the non-detection time width of the input signal can be set in advance using the input signal processing selection button 3 arranged on the operation panel 11 shown in FIG. A pulse group of the input signal included in this non-sensing time width is determined to be one pulse. That is, in the input signal processing unit 25, as shown in FIG. Signal processing is performed so as to sense as one pulse (a pulse representing one welding point).

For example, in the AC welding machine shown in FIG. 3(b), since the direction of current alternates with the commercial frequency, the input signal may be sensed multiple times. In the capacitor welding machine shown in Fig. 3(c), the electric charge stored in the capacitor is welded through the welding transformer. In order to prevent the phenomenon of so-called biased magnetism, there is also a device that causes a reset current 33 to flow in the direction opposite to the welding current after the end of welding. There are also welding machines and the like that energize multiple times for the purpose of stabilizing the welding strength. In order to cope with the above-described machining, the welding point monitoring device SC of this example has a function of arbitrarily setting the set time of the input signal shown in FIG. It is possible.

FIG. 4 is a flow chart showing an example of a welding point monitoring operation by the welding point monitoring apparatus SC of this embodiment. First, in step 41, the welding point monitoring device SC selects the operation mode IN/OUT. The operation mode IN is selected when performing monitoring such as when welding parts having different numbers of welding points for one processing head. The operation mode OUT is selected when a plurality of sensors 24a to 24d are connected to monitor welding operations by a plurality of processing heads or a plurality of types of processing heads. For example, when the operation mode IN is selected, the port 25a is selected as a monitoring port and only sensing signals from the sensor 24a are input. It is possible to monitor the welding operation of welding a plurality of members to the same product with different numbers of welding points using a single processing machine. On the other hand, when the operation mode OUT is selected, the monitoring ports are sequentially switched according to a predetermined port order, for example, the order of the ports 25a-25d, and the sensors connected to the respective ports 25a-25d are switched. Sensed signals 24a-24d are captured. It is possible to monitor the number of welding points by a plurality of processing machines equipped with sensors 24a-24d.

When the port set button 8 on the operation panel 11 is pressed for a long time to select the operation mode IN/OUT, the selection of the operation mode IN/OUT is toggled by the monitoring mode setting section 28A (see FIG. 2). When the operation mode IN is selected, IN of the IN/OUT lamp 8S is lit, and when the operation mode OUT is selected, OUT is lit.

The next step 42 is a process of setting the required number of welding points for each component. In this example, since four ports 25a to 25d are provided, set values a to d for the required number of welding points are assigned to the ports 25a to 25d by operation input.

The next step 43 is a step of setting the number of lots, that is, setting the required number of products. The required number of products is set by an operation input, and the value is set as the set value Ls.

In step 44, set values (required number of welding points) a to d are set as values S in accordance with the preset port order. First, the set value a assigned to the first port 25a is substituted for S. Thereby, the sensor 24a connected to the port 25a is selected, and the number of welding steps of the processing machine to which the sensor 24a is attached is monitored.

At step 47a, the counter 26a counts up the count value T based on the sensor signal of the sensor 24a input through the port 25a.

In step 45, the comparator 28 receives sensor input until the count value T of the counter 26a based on the sensing signal of the sensor 24a matches the set value S (=a), and when both values match, welding is completed. output a notification of That is, by emitting a warning sound and changing the lighting state of the port lamp 9a at the same time as performing the reset input, the operator is notified that the set number of welding has been completed.

When the operator recognizes the completion of processing of the port 25a (completion of processing by the processing machine to which the sensor 24a is attached) and performs a reset input in step 53, a reset operation is performed and a notification of welding completion is output. stops, and the count value T of the counter 26a is also returned to zero.

At step 46b, the comparison unit 28 determines whether or not the set value (required number of welding points) b of the count value is set for the port 25b next to the port 25a.

Here, when the operation mode IN is selected, the sensor input in step 47 after the report reset is from the same sensor 24a via the port 25a. The set value b assigned to the next port 25b is substituted for the set value S of the count value. On the other hand, when the operation mode OUT is selected, the sensor signal from the sensor 24b connected here is taken in via the next port 25b. The set value b assigned to the port 25b is substituted for the set value S of the count value. That is, the welding operation using the processing machine to which the sensor 24b is attached is monitored. In this operation mode OUT, when there is a sensor input through the ports 25a, 25c, and 25d that are not selected as monitoring ports, it is determined to be an erroneous production, and an error warning is issued to the operator to prompt the operator to stop the work. .

In both operation modes IN and OUT, if the required number of welding points is not set for the next port 25b (b=0), welding of one product is completed, and in step 50, Count up the number of lots L.

In this way, when the set value set to the port 25b in step 46b is 1 or more, the value of b is substituted for the value of S, and the sensor input is waited again in step 47b. Perform the same processing as Next, at step 46c, the comparison unit 28 further determines whether or not the next port setting, that is, the port 25c is set with a set value. If the set number is 1 or more, the process proceeds along the flow of NO in the flow chart, and the same processing as in the case of the ports 25a and 25b described above is performed.

In step 46c, if there is no setting in the port 25c (c=0), the comparison unit 28 indicates that the welding of the product is completed, outputs a welding completion notification, and informs the operator of the product by an alarm sound and a light source. Notify completion. In this case, it is desirable to use a sound source with a pattern different from that of the other ports for the alarm sound so that the operator can distinguish the sound only by hearing. In addition, the difference in sound sources in this case can be distinguished by a method of changing the ON-OFF pattern of sounds, a method of different frequencies, or a method of combining both.

When the operator recognizes the completion of the product and inputs the reset, the output of the notification of completion of welding is stopped, and the processing shown in step 50, that is, the count value L of the number of lots is counted up.

Next, in step 48, if the lot number count value L has not reached the lot number set value Ls set in step 43, the comparison unit 28 restarts the port for welding work on the next product. 25a, and when the count value L coincides with the set value Ls, an operation completion notification is output to notify completion of the lot number. For example, an audible alarm and, at the same time, a light source inform the worker that the set number of lots of finished products has been reached.

When the worker recognizes the completion of the product lot and inputs the reset, the notification of the completion of the work is stopped, and the reset operation is performed to return the lot number to zero (step 49). Waiting for sensor input via

Next, an example of monitoring the welding work for a plurality of parts to be welded to the same product using the welding point monitoring device SC will be described with reference to the specific fabrication drawing shown in FIG.

The parts SP1, SP2, SP3, and SP4 in FIG. 5 are joined to the product base part SPB by spot welding, respectively. Part SP1 means that it is spot-welded at three spots with a welding pitch of 80 mm, part SP2 means that it is spot-welded at two spots with a welding pitch of 40 mm, and part SP3 is spot-welded with a welding pitch of 20 mm. It means that both side portions are spot-welded with 2 welding points, a total of 4 welding points, and the part SP4 is spot-welded with 3 welding points at the same symmetrical positions as the part SP1.

The specific example shown in FIG. 5 is a case where machining is performed with the same machining head, and one sensor 24a monitors the work of welding four parts. Select the operating mode IN as the monitoring mode.

3 welding points, which is the number of welding points for the part SP1, is set to the port 25a as the set value a (number of required welding points) of the counter 26a, and 2 welding points for the part SP2 is set to the port 25b as the set value b, The port 25c is set with 4 dots of the component SP3 as the set value c, and the port 25d is set with 3 dots of the component SP4 as the set value d. In the case of operation mode IN, the number of setting values a to d is not restricted by the number of ports, and different numbers of setting values may be set.

If the welding conditions are an AC welder, 35 cycles, one cycle is 0.02 seconds in the 50 Hz region, resulting in a total welding pulse of 0.7 seconds. In this case, it is desirable to set the pulse time to about one second in consideration of the sensing error. That is, the input signal setting time (see FIG. 3) in the input signal processing section 25 is set to about 1 second.

Welding work for part SP1 is started, and when welding of 3 welding points, which is the required number of welding points, is completed, a warning sound is emitted from the main box MB and the remote box RB as a notification of the completion of welding, and at the same time, the welding completion of the part SP1 is indicated by the LED. inform the worker.

When the worker recognizes the end of the welding operation of the part SP1 and presses the reset switch 4 of the main box MB or the remote reset switch 16 of the remote box RB, the warning sound, which is the welding completion notification, is stopped and the next part is started. Move to monitoring of processing in SP2.

Up to part SP4, the process proceeds in the same manner as described above. When three welding points, which is the required number of welding points for part SP4, are completed, the worker issues an alarm sound, which is a welding completion notification, to inform the completion of the welding work for part SP4. , the completion of the work for the part SP4 is recognized. The notification in this case is a product completion notification indicating that the welding operation of a plurality of members for the same product has been completed. When the operator operates the reset switch 4 or the remote reset switch 16, the generated reset signal is input to count up the count value L of the number of lots, waiting for the next product to be welded, that is, through the port 25a again. The welding operation of the part SP1 to be monitored is awaited.

For the count value L of the number of lots, similarly to the counter value T of the welding points, a set value Ls can be designated, so that the number of manufactured products can be managed by inputting the set number of products.

During the above monitoring, if there is an input from the sensor 25a without canceling the welding completion notification, it means that excessive machining has been performed, and it is judged that there is a high possibility that the product will be defective. In this case, an error warning sound and an error display are performed to call the operator's attention.

Next, based on the specific manufacturing drawing shown in FIG. An example of monitoring when welding is described.

The welding diagram of the stud bolts is: Part ST1 has four M2.5 stud bolts with a length of 12 mm, part ST2 has eight stud bolts with a length of M3 of 15 mm, and part ST3 has a length of M4. It shows that one 10 mm stud bolt is machined at each location.

In this case, since the stud bolt holders of the processing heads differ depending on the size of each stud bolt, three processing heads 81a to 81c are used as shown in FIG. Sensors 24a to 24c are connected to ports 25a, 25b, and 25c of the main box MB of the welding point monitoring device SC, respectively. Each sensor 24a to 24c is attached to a portion of the power wiring for passing a machining current to each machining head indicated by reference numerals 82a to 82c in FIG. 8 to monitor the machining of each machining head.

As shown in FIG. 8, when a plurality of stud bolt processing heads can be attached to the stud bolt welding machine 80, sensors 24a to 24c are connected to positions 82a to 82c of the stud bolt processing heads 81a to 81c. This makes it easier to monitor. If only one processing head can be connected to one processing machine, the sensors 24a to 83c are placed at positions 83a to 83c of the power wiring of the processing head on the connection side to the stud bolt welding machine 80, as shown in FIG. 24c is desirable. This also has the effect of preventing incorrect wiring when replacing the machining head.

In the specific setting shown in FIG. 6, since machining is performed with a plurality of heads, three sensors are used to monitor the work of welding three types of parts. Port switching selects the operation mode OUT, which means switching of the external sensor.

Since the component ST1 has four locations where M2.5 stud bolts are welded, the set value a of the port 25a is set to 4. In addition, the set value b of the port 25b is set to 8 because the part ST2 has eight M3 stud bolt welding points. Since the part ST3 has one M4 stud bolt welding point, the set value c of the port 25c is set to 1.

After making the above settings, the part ST1, that is, the port 25a, is set as the monitoring port, and processing proceeds. The indicator lamps 18 of the sensors 24b and 24c, for which points are set, are kept lit. Also, the indicator lamp 18 of the sensor that has finished processing and is no longer a monitoring port is turned off. In this way, by changing the lighting mode of the indicator lamp 18 according to the operating state, it is possible to reduce the selection error of the head for processing.

When the processing head to which the sensor 24a, which is the object to be monitored with the blinking indicator light 18, senses the set number of four times, the operation of the port 25a is completed by the beep sound and the light source, which is the notification of the completion of welding. inform the worker. A reset input by the operator turns off the indicator light 18 of the sensor 24a of the port 25a, the next part ST2, that is, the port 25b is selected as the monitoring port, and the indicator light 18 of the sensor 24b connected here blinks. move. As a result, the operator is shown the machining head for the next machining and is prompted to carry out the machining operation.

When there is an input from a port other than the port being monitored, the operator is notified of the occurrence of a work error by means of an error warning sound, an error display, or the like. For example, when a signal is input from port 25a while monitoring port 25b, port 25b, that is, M3 is not processed, port 25a, that is, M2.5 is processed, and processing different from the drawing instruction is performed. This means that it is highly probable that a product defect has occurred.

When the processing of the port 25b ends, that is, when the counting of eight times ends, the operator is notified of the end of the operation of the port 25b by a beep sound and a light source. An operator who recognizes the end of port 25b receives a reset by pressing the reset button, the indicator light 18 of sensor 24b of port 25b is turned off, and component ST3, that is, the monitoring port is switched to port 25c and connected thereto. The indicator lamp 18 of the sensor 24c that is in the state of blinking changes to show the operator the machining head corresponding to the next port 25c, prompting the operator to carry out the machining operation.

When the processing of the port 25c, namely the stud bolt of M4, is completed, a warning sound, which is a notification that the processing of the stud bolt of the port 25c, namely M4, is completed, is sounded, and at the same time, the welding completion of the part ST3, namely the stud bolt of M4, is indicated by the light source. Notify workers.

When the operator recognizes the end of the port 25c and inputs the reset signal, an alarm sounds as a notification of product completion, and at the same time, the light source notifies the operator of the product completion.

The reset input by the operator causes the lot number display to be counted up, and the port 25a is switched to the monitoring port again to wait for the input of the sensor signal therethrough.

Note that the welding point monitoring device SC is specialized in counting the number of welding points in one product, so if a product defect such as a wrong welding point occurs during product production, or if a failure occurs for the purpose of checking the welding strength, It has a function to correct the count value of the welding spot monitoring device SC that counts other than non-defective products such as test processing by special operation of the operation panel.

The special operation in this case can be a method of entering a reverse mode by pressing a plurality of operation keys on the operation panel, or an operation method of operating while pressing a plurality of keys. It is desirable to prevent the count value from being unintentionally and erroneously reset, and to prevent the count value from being easily changed.

For example, if the welded part SP2 is welded at a deviation from the specified position, it means that the product has become defective during production. This product must be discarded during welding operations. In this case, by forcibly resetting the count of products by the special operation described above, it is possible to smoothly monitor products from the top port 25a again.

In this case, the work using the port 25b is interrupted in the middle, so the interrupt processing from step 51 in the flow chart shown in FIG. 4 is performed by a special operation on the panel. By interrupt processing, the count value is reset to zero, and the state of waiting for the first processing of the product shown in step 44 is entered.

In addition, when a defect is noticed after the lot value L is counted up, the count value T of welding spots and the count value L of the number of lots can be changed by a special operation such as simultaneous operation of a plurality of keys on the operation panel 11. It is desirable to have a function that enables subtraction or addition of count values L and T by operation.

1 count value display unit 2 lot value display unit 3 input signal processing selection button 4 reset switch 5 magnet type fixture 6 lot set button 7 shot set button 8 port set button 9 port indicator 10 frame 11 operation panel 11a panel fixture 12 Tone adjustment knob 16 Remote reset switch 17 Magnetic sensing unit 18 Indicator light 22 Display unit 23 Operation panel unit 24, 24a to 24d Sensor 25 Input signal processing unit 25a to 25d Ports 26a, 26b Counter 27 Count value setting unit 28 Comparison unit 28A Monitoring mode setting unit 29 Reporting unit 29R Remote reporting unit 31 Sensor input rise 32 Signal processing pulse rise 33 Reset current 70 Spot welding device 71 Position (on welding electrode)
72 position (below the welding electrode)
73 position (on sensor mount)
74 position (sensor mounting subordinate)
75 position (known toroidal coil installation location)
77 Position (remote box installation location)
78 position (main box installation location)
80 Stud bolt welding machine 81a Stud bolt holder for M2.5 81b Stud bolt holder for M3 81c Stud bolt holder for M4 82a to 82c Positions 83a to 83c Position SC Welding spot monitor MB Main box IB Control unit RB Remote box c-1 Wiring cable c-2 Wiring cable SW Power switch SP1 Spot welding part 1
SP2 spot welding part 2
SP3 spot welding part 3
SP4 spot welding part 4
SPB Spot product base part ST1 M2.5 stud bolt ST2 M3 stud bolt ST3 M4 stud bolt STB Stud product base part

Claims (17)

A portable main box with a built-in control unit for monitoring welding points,
a sensor that senses that spot welding has been performed for each welding point;
a remote box wired or wirelessly connected to the control unit;
and
The control unit is
a counter that counts the number of welding points sensed by the sensor;
a setting unit for presetting the required number of welding points;
a notification unit that outputs a notification of completion of welding when the count value of the counter reaches the required number of welding points set by the setting unit;
and
The remote box is
a remote reset switch operated to give a reset command to the control unit to stop the reporting by the reporting unit ;
a remote notification unit that outputs a welding completion notification in conjunction with the notification unit of the control unit;
and
A welding point monitoring device, wherein when the remote reset switch is operated, the reporting of the remote reporting unit is stopped . 2. The system according to claim 1, further comprising a reset switch arranged in said main box, which is operated to stop the output of said report by said reporting unit and reset the count value of said counter to zero. Welding point monitoring device. 3. The welding point monitoring device according to claim 1 , wherein the remote box has a magnet for magnetically attaching the remote box to another member. 4. The welding point monitoring device according to claim 1, 2 or 3, wherein the notification unit outputs the notification in a visually and audibly recognizable form. 5. The welding spot monitoring device according to claim 1, wherein said main box has a magnet for attaching said main box to another member by magnetic force. an operation panel connected by wiring so as to be rotatable around an axis perpendicular to the outer surface of the main box;
6. The welding point monitoring device according to claim 1, further comprising a panel fixture for fixing the operation panel at a predetermined rotational angular position about the axis. . main box and
a control unit incorporated in the main box;
and
The control unit is
an input operation unit;
a plurality of ports capable of inputting sensing signals of sensors attached to the spot welder to sense that spot welding has been performed;
a monitoring mode setting unit for setting the operation mode of welding spot monitoring to either single port mode or multiport mode;
a port selection/switching unit that selects one of the ports as a monitoring port in the single-port mode, and sequentially switches the ports used as the monitoring ports in the multi-port mode according to a predetermined port order; ,
In the single port mode, it is possible to set a plurality of required welding points for the monitoring port according to a predetermined setting order based on the input from the input operation unit, and in the multiport mode, the input operation a welding point setting unit that can set the required number of welding points for each of the ports based on an input from the unit;
a counter that counts the welding points of the spot welder based on the sensing signal of the sensor input to the monitoring port;
a notification unit that outputs a notification of completion of welding when the count value of the welding points by the counter reaches the required number of welding points set for the monitoring port;
a reset switch operated to stop the output of the notification by the notification unit and perform a reset operation to return the count value of the counter to zero;
and
In the single-port mode, the port selection/switching unit switches the required number of welding points set for the monitoring port according to the setting order each time the reset operation is performed, and in the multi-port mode, A welding point monitoring device, wherein the monitoring port is switched according to the order of the ports each time the reset operation is performed. The control unit is
a lot number setting unit capable of setting the lot number of the product to be welded based on the input from the input operation unit;
a lot number counter that counts up a lot number count value after the report is output and the reset operation is performed for each of the set required welding points;
and
The notification unit outputs a product completion notification when the lot number count value reaches a lot number setting value set by the lot number setting unit,
8. The welding point monitoring device according to claim 7, wherein when the reset switch is operated, a reset operation is performed to stop the output of the report and return the lot number count value of the lot number counter to zero. The control unit includes an input signal processing unit that sets a period from the rise of the sensing signal to the elapse of a set time as one pulse, and masks fluctuations in the sensing signal during the set time,
The counter is configured to perform a count-up operation for each pulse,
8. The welding point monitoring device according to claim 7, wherein the set time can be set and changed by input from the input operation section. 8. The welding point monitoring device according to claim 7, wherein the notification unit outputs the notification in a visually and audibly recognizable form. 8. The welding point monitoring device according to claim 7, wherein the main box has a magnet for attaching the main box to another member by magnetic force. an operation panel rotatably connected to the outer surface of the main box about an axis orthogonal to the outer surface;
and a panel fixture that fixes the operation panel at a predetermined rotational angle position about the axis,
8. The welding point monitoring device according to claim 7, wherein the operation panel is equipped with the input operation section and the reset switch. It has a remote box that is wired or wirelessly connected to the control unit,
The remote box includes a remote reset switch operated to stop the output of the notification by the notification unit and reset the count value of the counter to zero,
8. The welding point monitoring device according to claim 7, wherein said reset operation is performed when either said reset switch or said remote reset switch is operated. The remote box includes a remote notification unit that outputs a welding completion notification when the count value of the welding points counted by the counter reaches the required number of welding points set for the monitoring port,
14. The welding point monitoring device according to claim 13, wherein the notification of the remote notification unit is stopped when either the reset switch or the remote reset switch is operated. 14. The welding point monitoring device according to claim 13, wherein the remote box has a magnet for magnetically attaching the remote box to another member. at least one sensor mounted on the spot welder for sensing that a spot weld has occurred;
The sensor is
a magnetic sensing unit that senses a rotating magnetic field of a processing current of a processing machine to which the sensor is attached;
8. The welding point monitoring device according to claim 7, further comprising a status indicator lamp which lights in a predetermined manner when said port to which said sensor is connected is set or selected as said monitoring port. The control unit has a display,
The display unit
port indicator lights for indicating the status of each of the ports;
a mode display lamp for displaying the set operation mode of the welding point monitoring;
a count value display unit for displaying the count value of the counter,
The input operation unit
a mode setting operation member that is operated to set and input an operation mode for monitoring the welding point;
an operation member for inputting the number of welding points operated to input and set the required number of welding points;
The weld spot monitoring device according to claim 7, comprising:

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