JP2015066848A - Welding device and welding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a welding device having a stable welding performance.SOLUTION: A welding device include: a handler 1 having a heating part, which transports a sheet to a predetermined position and welds the sheet with the heating part; a temperature sensor which detects the temperature of the heating part; and a control part 30 which adjusts the temperature of the heating part such that the detection temperature of the temperature sensor becomes a preset temperature, allows the handler 1 to repeat the transportation and welding of the sheet for a welding processing in response to an instruction for starting the processing, and halts the handler 1 before the start and after the completion of welding processing. The control part 30 sets a preset temperature at a first preset value before starting the welding processing and during a period from the start of the welding processing until a first preset time period elapses. After the first preset time period elapses, the preset temperature is changed to a second preset value which is lower than the first preset value.

Description

  The present invention relates to a welding apparatus and a welding method for welding sheets.

  While miniaturization, high quality, and safety of electronic parts are required, a resin sheet or the like is used as a member that reliably insulates between terminals through which current flows. This misalignment or poor welding of the resin sheet causes a serious accident such as a short circuit. For this reason, it is required to reliably align and weld the resin sheet.

  Patent Documents 1 and 2 disclose that two or more resin sheets are stacked and welded. For the welding of the resin sheets, for example, a welding apparatus in which a mechanism for conveying the resin sheets and a mechanism for welding the resin sheets are separately provided are used.

  In the welding apparatus, the transport mechanism transports the resin sheet to the welding position, and after the resin sheet leaves the transport mechanism, the welding mechanism welds the resin sheet.

  However, in the above welding apparatus, when the resin sheet moves away from the transport mechanism, the resin sheet may be misaligned, so it is difficult to align the resin sheet with high accuracy. Further, the switching operation between the transport mechanism and the welding mechanism decreases productivity and increases manufacturing cost.

  In view of this, a welding apparatus including a handler in which a transport mechanism and a welding mechanism are integrated has been proposed. In this welding apparatus, the handler moves the first resin sheet on the first stage to the second stage, and aligns the first resin sheet with the second resin sheet on the second stage. Thereafter, the first resin sheet is overlapped and welded to the second resin sheet. In this case, since there is no need to switch between the transport mechanism and the welding mechanism, the above-described problems of the positional deviation of the resin sheet and the decrease in productivity do not occur.

  Normally, in the welding apparatus, temperature control is performed so that the heater temperature becomes a predetermined set temperature in order to stabilize the welding performance of the heater.

  As another example of temperature control, Patent Document 3 describes a heater temperature control method in which heat treatment is performed intermittently. In this temperature control method, the temperature rise characteristic immediately after the heat treatment and the temperature drop characteristic of the heater due to natural heat dissipation are obtained in advance. Based on the temperature drop characteristics, predict the heater drop temperature from the end of the previous seal process to the start of the current seal process, and start the current seal process from the predicted drop temperature based on the temperature rise characteristics The heater is heated by obtaining the heating time until the seal proper temperature is reached immediately before.

  The temperature control described in Patent Document 3 can be applied to a welding apparatus including the handler.

JP-A-9-213377 Japanese Patent Laid-Open No. 7-302616 JP 2003-341626 A

  However, in the welding apparatus equipped with the above-described handler, the heater cools down due to the cooling effect caused by the airflow generated during transportation, or after the transportation stops, the cooling action due to the airflow during transportation stops, so the heater temperature rises excessively. To do. For this reason, the following problems arise only by performing temperature control so that the temperature of the heater becomes a predetermined set temperature.

  FIG. 6 shows the temperature control from the standby state where the product is not being processed (when the handler is stopped) to the time when the product process (welding process) for processing a plurality of products is performed and the product returns to the standby state again. It is a figure for demonstrating.

  In FIG. 6, during the product processing, the handler reciprocates between the first and second stages and repeats the welding of the resin sheet. The heater temperature T3 indicates a change in the temperature of the heater detected by the temperature sensor. The upper temperature limit and the lower temperature limit correspond to the upper and lower limits of the allowable welding temperature range, respectively. The heater set temperature T4 is an intermediate value (standard center) between the upper limit and the lower limit.

  In the standby state (when the handler is stopped), temperature control (feedback control) is performed so that the heater temperature becomes the heater set temperature T4. As a result, the heater temperature T3 is maintained at the heater set temperature T4.

  However, during product processing, the heater is cooled by the airflow generated by the handler transport operation, so the heater temperature T3 temporarily falls to a temperature lower than the lower limit of the allowable welding temperature range. After a while, the heater temperature T3 rises by feedback control. If the handler's reciprocating operation is regularly performed at a substantially constant cycle, the cooling action by the airflow and the heater temperature control are balanced, and the heater temperature is maintained at the heater set temperature T4. After that, when the product processing is finished and the handler is stopped, the cooling effect by the air current is lost, so the heater temperature rises temporarily.

  The temperature change of the heater causes a problem that the heater temperature is lowered to a temperature lower than the lower limit of the allowable range of the welding conditions immediately after the start of the product processing, resulting in a problem of insufficient welding.

  When the temperature control described in Patent Document 3 is applied to a welding apparatus equipped with the above-described handler, the heating condition of the heater and the state of natural heat dissipation change depending on the handling operation of the handler. Then, stable welding performance cannot be obtained.

  Note that by reducing the size of the heater and reducing the heat capacity, it is possible to speed up the responsiveness of temperature control and stabilize the heater temperature. However, in this case, in order to cover a wide welding area such as a resin sheet, a large number of temperature measuring mechanisms such as a heater and a thermocouple and a device for controlling the temperature are required, resulting in an expensive mechanism.

  The objective of this invention is providing the welding apparatus and the welding method which can solve the said problem and can provide the stable welding performance.

In order to achieve the above object, according to one aspect of the present invention,
A handler that includes a heating unit, conveys the sheet to a predetermined position, and welds the sheet by the heating unit;
A temperature sensor for detecting the temperature of the heating unit;
The temperature of the heating unit is adjusted so that the temperature detected by the temperature sensor becomes a set temperature, and in accordance with a processing start instruction, a welding process is performed in which the sheet is repeatedly conveyed and welded by the handler, and the welding is performed. A control unit that stops the handler before and after the start of processing,
The control unit holds a first set value and a second set value lower than the first set value, and before the start of the welding process and a first predetermined time from the start of the welding process. Until the time elapses, the set temperature is set to the first set value, and the set temperature is changed from the first set value to the second set value after elapse of the first predetermined time. A welding apparatus is provided.

According to another aspect of the present invention,
A welding method including a heating unit, transporting a sheet to a predetermined position and welding the sheet to be welded by the heating unit;
The temperature sensor detects the temperature of the heating part,
With the handler stopped, the temperature of the heating unit is adjusted so that the temperature detected by the temperature sensor becomes the first set temperature,
When receiving a processing start instruction in a state where the temperature of the heating unit is maintained at the first set temperature by the adjustment, a welding process for repeatedly performing sheet conveyance and welding by the handler is performed,
Until the predetermined time has elapsed from the start of the welding process, the temperature of the heating unit is adjusted so that the temperature detected by the temperature sensor becomes the first set temperature,
After the elapse of the predetermined time, a welding method is provided in which the temperature of the heating unit is adjusted so that the temperature detected by the temperature sensor becomes a second set temperature lower than the first set temperature.

  According to the present invention, stable welding performance can be provided, and the quality of the welded state can be stabilized.

It is a block diagram which shows the structure of the welding apparatus which is one Embodiment of this invention. It is an external view when the handler of the welding apparatus shown in FIG. 1 is seen from the front. It is a block diagram which shows an example of the structure which concerns on the temperature control of the heater of the welding apparatus shown in FIG. It is a figure for demonstrating the temperature control performed with the welding apparatus shown in FIG. It is a flowchart which shows the setting temperature change procedure performed with the welding apparatus shown in FIG. It is a figure for demonstrating the temperature control performed with the welding apparatus provided with the handler which integrated the conveyance mechanism and the welding mechanism.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a welding apparatus according to an embodiment of the present invention.

  Referring to FIG. 1, the welding apparatus conveys the stage 7 to which the resin sheet 21 is supplied, the stage 8 to which the resin sheet 22 is supplied, and the resin sheet 21 on the stage 7 to the stage 8. A handler 1 that accurately positions and welds the resin sheet 22, temperature sensors 3 a to 3 d (not shown), an input unit 40, stages 7 and 8, and a control unit 30 that controls the handler 1 are included.

  The input unit 40 includes input means such as buttons and a keyboard, and supplies a signal corresponding to the input operation by the operator to the control unit 30. The control unit 30 receives an input operation by the operator via the input unit 40. For example, the operator can use the input unit 40 to instruct the start of the welding process, and various information including information necessary for the welding process (processing man-hour, welding time, heater set temperature, etc.). Information can be entered.

  Each of the stages 7 and 8 has a suction mechanism on the upper surface. Resin sheets 21 and 22 are supplied to the stages 7 and 8 from the external sheet supply device. The resin sheet 21 is adsorbed by the adsorption mechanism of the stage 7, and the resin sheet 22 is adsorbed by the adsorption mechanism of the stage 8.

  The handler 1 includes a conveyance unit 1a that can move in the XYZ directions, an adsorption unit 11 that adsorbs a sheet, and four heaters 2a to 2d provided on four side surfaces of the conveyance unit 1a. The adsorption unit 11 includes an adsorption mechanism for adsorbing the sheet to the bottom surface.

  FIG. 2 shows an external view of the handler 1 when viewed from the front (the heater 2c side).

  As shown in FIG. 2, the suction unit 11 is attached to the transport unit 1 a via the movable unit 20. The heaters 2a, 2b, and 2c are attached to the transport unit 1a via movable parts 21a, 21b, and 21c, respectively. Although not shown in FIG. 2, the heater 2d is also attached to the transport unit 1a via the movable unit 21d.

  The movable parts 20, 21a, 21b, 21c, 21d are made of, for example, spring-like movable means. The movable direction of the movable portion 20 is a direction (Z direction) perpendicular to the bottom surface of the suction portion 11. The movable direction of the movable portions 21a to 21d is also the Z direction. The height in the Z direction (height from the resin sheet) of the suction portion 11 can be adjusted by the movable portion 20, and the height in the Z direction of each of the heaters 2a to 2d (resin sheet) by the movable portions 21a to 21d. Height) can be adjusted.

  The height of the suction part 11 and the heaters 2a to 2d is the lowest in the suction part 11. The heights of the heaters 2a, 2b, 2c, and 2d are substantially the same. When the resin sheet is welded, the transport unit 1a is lowered to a height at which all of the adsorption unit 11 and the heaters 2a to 2d are in contact with the resin sheet. At this time, since the movable parts 20, 21a, 21b, 21c, and 21d are contracted, all of the adsorption part 11 and the heaters 2a to 2d can come into contact with the resin sheet. In this state, the resin sheets are welded by the heaters 2a to 2d.

  Here, operation | movement of the stages 7 and 8 and the handler 1 at the time of welding a resin sheet is demonstrated easily.

  First, the transport unit 1 a moves onto the stage 7. Then, the transport unit 1 a is lowered to a height at which the suction unit 11 contacts the sheet 21. At this time, the heaters 2a, 2b, 2c, and 2d do not contact the resin sheet 21.

  After the transport unit 1a is lowered, the suction unit 11 sucks the resin sheet 21. After the adsorbing unit 11 adsorbs the resin sheet 21, the adsorption of the resin sheet 21 by the stage 7 is released. Thereby, delivery of the resin sheet 21 to the handler 1 becomes possible.

  After releasing the adsorption of the resin sheet 21 by the stage 7, the transport unit 1 a moves up and moves onto the stage 8 to align the resin sheet 22 on the stage 8 and the resin sheet 21 adsorbed to the adsorption unit 11. Do. The resin sheet 21 is overlaid on the resin sheet 22 on the stage 8 and the adsorbing portion 11 and the heaters 2a, 2b, 2c, and 2d are all overlaid (hereinafter also referred to as a welded body). ) Is lowered to a height at which it comes into contact with (). At this time, the adsorbing part 11 comes into contact with the adherend (resin sheets 21 and 22) due to the contraction of the movable part 20, and the heaters 21a, 21b, 21c and 21d due to the contraction of the movable parts 21a, 21b, 21c and 21d, respectively. . In this state, the resin sheets 21 and 22 are welded by the heaters 2a to 2d. Although the heater temperature at the time of welding is determined by the material of the resin sheet, it is desirable to set the temperature so that the welding can be performed in a short time such as several ms to several hundred ms from the viewpoint of productivity.

  After the elapse of the welding time based on the welding conditions obtained in advance from the contact between the heaters 2a, 2b, 2c, and 2d and the adherend, the adsorption of the resin sheet 22 by the adsorption unit 11 is released. And the conveyance part 1a raises to the height which all the adsorption | suction part 11 and heater 2a, 2b, 2c, 2d leave | separate from the welding body of the resin sheet 21 and the resin sheet 22. FIG.

  The adsorption of the resin sheet 22 by the stage 8 is released. Thereby, delivery of the welded body of the resin sheets 21 and 22 to the external sheet discharging apparatus can be performed.

  Returning again to the description with reference to FIG.

  The control unit 30 controls the movement of the transport unit 1a, adsorption and desorption of the adsorption unit 11, temperature control of the heaters 2a to 2d, measurement and control of the welding time of the heaters 2a to 2d, adsorption and desorption of the stages 7 and 8. I do. For temperature control of the heaters 2a to 2d, a method of performing heater on / off control (control of energization time), a method of controlling the amount of electric power (or current) supplied to the heater, and the like can be applied. The former method includes, for example, temperature control using a thermostat or a thyristor.

  FIG. 3 shows an example of a configuration relating to the temperature control of the heater.

  As shown in FIG. 3, the temperature sensors 3a to 3d detect the temperatures of the heaters 2a to 2d, respectively, and output values indicating the detected temperatures. Outputs of the temperature sensors 3 a to 3 d are supplied to the control unit 30.

  The control unit 30 includes a temperature controller 31, a storage unit 32, and a timer 33. The storage unit 32 holds temperature set values S1 to S3 (S1> S2> S3). The temperature set values S1 to S3 are within a welding allowable temperature range that satisfies the welding conditions of the resin sheets 21 and 22.

  The temperature set value S2 may be, for example, a value (center of specification) between the upper limit value and the lower limit value of the welding allowable temperature range. Further, it is desirable that the temperature set value S1 is a value having a certain margin from the upper limit value of the allowable welding temperature range. Similarly, the temperature set value S3 is desirably set to a value having a certain margin from the lower limit value of the allowable welding temperature range.

  In the welding of the resin sheet, there is a certain allowable range determined by the welding temperature and the welding time. The allowable range of the welding temperature is not less than the resin sheet melting temperature, and the upper limit is generally about 30 ° C. to 50 ° C. depending on the welding time. On the other hand, the welding time ranges from several tens of ms to several seconds. In general, in order to realize a high-speed welding process, it is desirable to have a short welding time at the highest possible welding temperature.

  The control unit 30 controls the temperature of the heaters 2a to 2d so that the detected temperatures of the temperature sensors 3a to 3d become the set temperatures, respectively, and conveys the sheet by the handler 1 in response to a processing start instruction from the input unit 40. Then, a welding process for repeatedly performing the welding is executed, and the handler 1 is stopped before and after the welding process is started.

  In the temperature control, the temperature controller 31 sets the set temperature to the temperature set value S1 before the start of the welding process, and after the predetermined time has elapsed after the start of the weld process, the temperature controller 31 sets the set temperature from the temperature set value S1. Change to temperature set value S2. In addition, the temperature controller 31 changes the set temperature from the temperature set value S2 to the temperature set value S3 at a time before a predetermined time before the end of the welding process. Furthermore, the temperature controller 31 changes the set temperature from the temperature set value S3 to the temperature set value S1 after a predetermined time has elapsed after the end of the welding process.

  The temperature controller 31 changes the change timing from the temperature set value S1 to the temperature set value S2 after the start of the welding process, the elapsed time from the start of the process, the number of times of welding, or the change in the output of the temperature sensor (change in the differential value). Judge from either. Further, the temperature controller 31 determines the change timing from the temperature set value S2 to the temperature set value S3 before the end of the welding process from the number of welding times (processing man-hours). In addition, the temperature controller 31 changes the change timing from the temperature set value S3 to the temperature set value S1 after the end of the welding process, either the elapsed time from the end of the process or the change in the output of the temperature sensor (change in the differential value). Judge from.

  The control unit 30 monitors the operation of the temperature sensors 3a to 3d, the stages 7 and 8, and the handler 1 (operations of the transport unit 1a and the heaters 2a to 2d), and if any abnormality occurs, an alarm is generated. Is configured to occur. When an alarm is generated during the welding process, the temperature controller 31 forcibly sets the set temperature to the temperature set value S1 in response to the occurrence of the alarm (stop instruction). Also, when receiving a signal (stop instruction) to stop the handler 1 from the input unit 40 or an external device during the welding process, the temperature controller 31 forcibly sets the set temperature to the temperature set value S1. To do.

  Below, the said temperature control is demonstrated concretely.

  FIG. 4 is a diagram for explaining the temperature control from the standby state until the product process (welding process) for continuously processing a plurality of products is performed and the process again returns to the standby state. Here, temperature control of the heater 2a will be described as an example.

  In FIG. 4, time 42 indicates a period during which product processing is being executed. Time 41 indicates a period of a standby state before the start of product processing, and time 43 indicates a period until the standby state after the end of product processing. During the period of time 41 and time 43, the handler 1 is stopped. During the period of time 42, the conveyance and welding of the resin sheet by the handler 1 are repeated.

  The heater temperature T1 indicates a change in the temperature of the heater 2a. The change in the temperature of the heater 2a corresponds to the change in the output of the temperature sensor 3a. The heater set temperature T2 indicated by the thick rectangular wave line indicates the change timing between the temperature set values S1 to S3. The upper temperature limit and the lower temperature limit correspond to the upper and lower limits of the allowable welding temperature range, respectively.

  The process start time 44 is a time for giving a change timing from the temperature set value S1 to the temperature set value S2 after the product process is started. The pre-processing time 45 is a time for giving a change timing from the temperature setting value S2 to the temperature setting value S3 during the product processing. The post-processing time 46 is a time for giving a change timing from the temperature setting value S3 to the temperature setting value S1 after the product processing is completed.

  In general, the time 44 after the process is started is a time when the heater temperature T1 is minimum after the process is started. Further, the pre-processing time 45 is generally set to the maximum time that satisfies the welding condition by preheating even when the heater output is stopped during the processing. Further, the post-processing time 46 is generally set to a time for the heater temperature T1 to rise and turn down after the handler 1 stops.

  Referring to FIG. 4, in the period of time 41, the temperature controller 31 sets the set temperature T2 of the heater 2a to the temperature set value S1. Then, the temperature controller 31 adjusts the temperature of the heater 2a so that the temperature detected by the temperature sensor 3a becomes the temperature set value S1. By this adjustment, a standby state is maintained in which the temperature T1 of the heater 2a is maintained at a temperature corresponding to the temperature set value S1.

  In the standby state, when receiving a processing start instruction, the control unit 30 starts product processing. The period during product processing is time 42. The temperature controller 31 starts the timer 33 at the processing start timing, and measures the elapsed time from the start of the processing.

  The temperature controller 31 maintains the set temperature T2 of the heater 2a at the temperature set value S1 until the elapsed time measured by the timer 33 reaches the time 44 after the start of processing. In this maintenance period, during the product processing, the heater 2a is cooled for the conveyance and welding of the resin sheet by the handler 1. Due to this cooling action, the temperature T1 of the heater 2a decreases.

  Before the temperature T1 of the heater 2a reaches the lower temperature limit, the elapsed time measured by the timer 33 reaches the time 44 after the start of processing. When the elapsed time reaches time 44 after the start of processing, the temperature controller 31 changes the set temperature T2 of the heater 2a from the temperature set value S1 to the temperature set value S2, and the detected temperature of the temperature sensor 2a changes to the temperature set value S2. Thus, the temperature of the heater 2a is adjusted. By this control, the temperature T1 of the heater 2a rises and is maintained at a temperature corresponding to the temperature set value S2.

  The temperature controller 31 changes the set temperature T2 of the heater 2a from the temperature set value S2 to the temperature set value S3 before the end of the product process and at the time 45 before the process ends, and the detected temperature of the temperature sensor 2a The temperature of the heater 2a is adjusted so as to become the temperature set value S3. By this adjustment, the temperature T1 of the heater 2a decreases.

  The temperature controller 31 is preliminarily given a processing man-hour (number of welding times) in product processing. The temperature controller 31 predicts the time until the product processing is completed based on the processing man-hour (number of welding times), and ends the processing based on the elapsed time from the processing start measured by the timer 33 and the predicted end time. The timing at which the previous time 45 is reached can be determined.

  During the period 45 before the end of processing, the temperature T1 of the heater 2a further decreases in order to maintain the set temperature T2 of the heater 2a at the temperature set value S3, but before the temperature T1 of the heater 2a reaches the lower temperature limit, Product processing ends.

  When the product process ends, the temperature controller 31 resets the timer 33 and restarts, and measures the elapsed time after the process ends.

  The temperature controller 31 maintains the set temperature T2 of the heater 2a at the temperature set value S3 until the elapsed time measured by the timer 33 reaches the time 46 after the end of the process. Since the handler 1 is stopped during this maintenance period, the above-described cooling action due to the conveyance and welding of the resin sheet does not occur. Therefore, the temperature T1 of the heater 2a increases.

  Before the temperature T1 of the heater 2a reaches the upper temperature limit, the elapsed time measured by the timer 33 reaches the time 46 after the end of processing. When the elapsed time reaches time 46 after the end of processing, the temperature controller 31 changes the set temperature T2 of the heater 2a from the temperature set value S3 to the temperature set value S1, and the detected temperature of the temperature sensor 2a changes to the temperature set value S1. Thus, the temperature of the heater 2a is adjusted. As a result of this adjustment, the temperature T1 of the heater 2a decreases, and a standby state maintained at a temperature corresponding to the temperature set value S1 is established.

  Similar to the temperature control of the heater 2a, the temperature controller 31 performs temperature control of the heaters 2b to 2d.

  In the temperature control described above, the temperature controller 31 can determine the change timing of the temperature set values S1 to S3 without using the timer 33.

  For example, the temperature controller 31 detects a change from a decrease in temperature detected by the temperature sensor to an increase after the start of product processing, determines the detection time of the change as the time 44 after the start of processing, and sets the set temperature T2 may be set to the temperature set value S1.

  In addition, the number of man-hours (number of times of welding) for sheet conveyance and welding by the handler 1 is held in the storage unit 32, and the temperature controller 31 calculates an unprocessed man-hour from the man-hours held in the storage unit 32 and the execution man-hours. Then, it may be determined that the time when the unprocessed man-hour has reached a preset value is the time when the pre-processing time 45 is reached, and the set temperature T2 may be changed from the temperature set value S1 to the temperature set value S2.

  In addition, the temperature controller 31 detects a change from an increase to a decrease in the temperature detected by the temperature sensor after the product processing is completed, determines that the change detection time is an elapsed time 46 after the processing is completed, and sets the set temperature T2 may be changed from the temperature set value S3 to the temperature set value S1.

  Next, the procedure for changing the set temperature will be specifically described.

  FIG. 5 is a flowchart showing a set temperature changing procedure. Hereinafter, the set temperature changing procedure will be described with reference to FIGS. 4 and 5.

  First, the temperature controller 31 sets the set temperature T2 to the temperature set value S1, and adjusts the temperature of the heater so that the temperature detected by the temperature sensor becomes the temperature set value S1 (step 60). By this adjustment, the heater temperature is maintained at the temperature set value S1 (standby state).

  Next, the control unit 30 determines whether or not a processing start instruction has been received (step 61). If the process start instruction has not been received, the process proceeds to step 60. When the processing start instruction is received, the control unit 30 starts product processing (welding processing).

  After starting the product process, the temperature controller 31 determines whether or not the time 44 after the process has started (or whether or not the temperature detected by the temperature sensor has been switched from a decrease to an increase) (step 62).

  If the determination result in step 62 is “Yes”, the temperature controller 31 sets the set temperature T2 to the temperature set value S2 (change from the temperature set value S1 to the temperature set value S2), and the detected temperature of the temperature sensor. The heater temperature is adjusted so that becomes the temperature set value S2 (step 63).

  Next, the temperature controller 31 determines whether or not the pre-processing time 45 has been reached (or whether or not the unprocessed man-hour has reached a predetermined value) (step 64).

  When the determination result in step 64 is “Yes”, the temperature controller 31 sets the set temperature T2 to the temperature set value S3 (change from the temperature set value S2 to the temperature set value S3), and the detected temperature of the temperature sensor. The heater temperature is adjusted so that becomes the temperature set value S3 (step 65). If the determination result in step 64 is “Yes”, the process proceeds to step 63.

  When the product process ends, the temperature controller 31 determines whether or not the time 46 after the process has elapsed (or whether or not the temperature detected by the temperature sensor has changed from rising to falling) (step 66).

  If the determination result in step 66 is “Yes”, the process proceeds to step 60. If the determination result in step 66 is “No” and an instruction to start the next product process is received (step 67), the process proceeds to step 61.

  If the process is terminated due to some abnormality during product processing, the process immediately proceeds to step 60. However, in this case, the control unit 30 prohibits the start of product processing until a preset time has elapsed. After the preset time has elapsed, the control unit 30 resumes product processing. Here, some abnormality includes generation of an alarm (stop instruction) and a stop instruction from the input unit 40 or an external device.

  The above-described set temperature changing procedure is performed for each of the heaters 2a to 2d.

  According to the welding apparatus of this embodiment mentioned above, there exist the following effects.

  The temperature control shown in FIG. 6 has a problem that the welding temperature becomes insufficient because the heater temperature falls to a temperature lower than the lower limit of the allowable welding temperature range immediately after the start of product processing. On the other hand, according to the welding apparatus of the present embodiment, it is possible to minimize a change in the heater temperature due to the cooling action due to the transport of the handler by appropriately switching the set temperature according to the operation state. Stable welding performance can be provided. Thereby, the resin sheet can be welded under optimum welding conditions, and the quality of the welded state can be stabilized.

  Further, in the temperature control shown in FIG. 6, since the heater temperature rises to a temperature higher than the upper limit of the allowable welding temperature range after the handler is stopped, the product process is started immediately after the product process is completed, or the product process is temporarily stopped. If the product processing is resumed immediately after stopping, there is a problem that the resin sheet is welded at a temperature higher than the upper limit of the allowable welding temperature range, resulting in excessive welding. On the other hand, according to the welding apparatus of the present embodiment, since the change in the heater temperature after the handler is stopped can be minimized, the product processing is started immediately after the product processing is completed, or the product processing is performed. Even when the product processing is resumed immediately after the suspension of the resin, the resin sheet can be welded under optimum conditions, and the quality of the welded state can be stabilized.

  Further, since it is not necessary to add a special mechanism, the cost can be reduced.

  In addition, in the welding apparatus of this embodiment, although the heating part of the handler 1 consists of four heaters 2a-2d, it is not limited to this. The number of heaters in the heating unit is one or more.

  Moreover, although the control part 30 performs a welding process (product process) according to the start instruction from the input part 40, a start instruction may be supplied from an external device.

  Further, when the resin sheets 21 and 22 are supplied to the stages 7 and 8, respectively, a signal indicating that fact (a trigger corresponding to the start instruction) is supplied to the control unit 30, and the control unit 30 supplies the stages 7 and 8 to each other. When the signals from both are received, the welding process (product process) may be executed.

  Moreover, although the four temperature sensors 3a-3d are used with respect to the four heaters 2a-2d, it is not limited to this. One or more temperature sensors may be provided for one or more heaters. For example, one temperature sensor may be provided for any of the four heaters 2a to 2d.

  Moreover, the movable parts 20, 21a, 21b, 21c, and 21d are not limited to spring-like movable means. For example, any movable means may be used as long as it can move in the vertical direction, such as an air cylinder.

  INDUSTRIAL APPLICABILITY The present invention can be applied to all apparatuses that transport and weld a weldable member (sheet-like one) to a predetermined position. However, when the members that can be welded are welded, it is desirable that the members have substantially the same melting point.

DESCRIPTION OF SYMBOLS 1 Handler 1a Conveyance part 2a-2d Heater 3a-3d Temperature sensor 7, 8 Stage 11 Adsorption part 30 Control part 40 Input part

Claims (10)

A handler that includes a heating unit, conveys the sheet to a predetermined position, and welds the sheet by the heating unit;
A temperature sensor for detecting the temperature of the heating unit;
The temperature of the heating unit is adjusted so that the temperature detected by the temperature sensor becomes a set temperature, and in accordance with a processing start instruction, a welding process is performed in which the sheet is repeatedly conveyed and welded by the handler, and the welding is performed. A control unit that stops the handler before and after the start of processing,
The control unit holds a first set value and a second set value lower than the first set value, and before the start of the welding process and a first predetermined time from the start of the welding process. Until the time elapses, the set temperature is set to the first set value, and the set temperature is changed from the first set value to the second set value after elapse of the first predetermined time. , Welding equipment.   The first or second set value is set within an allowable welding temperature range in which the sheet can be welded by the heating unit, and the second set value is an upper limit and a lower limit of the allowable welding temperature range. The welding apparatus according to claim 1, wherein the welding apparatus has an intermediate value.   The control unit detects a change from a decrease in temperature detected by the temperature sensor to an increase after the start of the welding process, and determines the detection time of the change as a time when the first predetermined time has elapsed. Item 3. The welding apparatus according to Item 1 or 2.   The control unit further holds a third set value lower than the second set value, and sets the set temperature at the second set time at a time before a second predetermined time after the end of the welding process. The welding apparatus according to claim 1, wherein the welding apparatus changes from a value to the third set value.   The welding apparatus according to claim 4, wherein the third set value is set within a welding allowable temperature range in which the sheet can be welded by the heating unit.   6. The welding apparatus according to claim 4, wherein the control unit determines that a time when an unprocessed man-hour in the welding process reaches a preset value is a time before the second predetermined time.   The welding apparatus according to claim 4, wherein the control unit maintains the third set value until a third predetermined time elapses after the welding process is finished.   The control unit detects a change from an increase in temperature detected by the temperature sensor to a decrease after the end of the welding process, and determines the detection time of the change as a time when the third predetermined time has elapsed. Item 8. The welding apparatus according to Item 7.   The said control part sets the said setting temperature to a said 3rd setting value, when stopping the said handler according to a stop instruction | indication during the said welding process, The any one of Claims 4 thru | or 8 Welding equipment. A welding method including a heating unit, transporting a sheet to a predetermined position and welding the sheet to be welded by the heating unit;
The temperature sensor detects the temperature of the heating part,
With the handler stopped, the temperature of the heating unit is adjusted so that the temperature detected by the temperature sensor becomes the first set temperature,
When receiving a processing start instruction in a state where the temperature of the heating unit is maintained at the first set temperature by the adjustment, a welding process for repeatedly performing sheet conveyance and welding by the handler is performed,
Until the predetermined time has elapsed from the start of the welding process, the temperature of the heating unit is adjusted so that the temperature detected by the temperature sensor becomes the first set temperature,
The welding method of adjusting the temperature of the heating unit so that the temperature detected by the temperature sensor becomes a second set temperature lower than the first set temperature after the predetermined time has elapsed.

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