Conveying systems and conveying modules

Abstract

The conveying system (1) comprises: at least two conveying modules (100) having a coil group (102) and an inverter unit (103) for applying an AC voltage to the coil group (102); and at least one trolley (200) carrying a magnet (202) receiving an electromagnetic force from the coil group (102). Each inverter unit (103) comprises: an inverter circuit (104) to which a DC voltage outputted from a DC power supply (400) is applied and which converts the DC voltage into an AC voltage; and a diode (107) configured to be connected between the DC power supply (400) and the inverter circuit (104) and to allow a positive current to flow from the first side toward the second side when the potential of the first side connected to the DC power supply (400) is higher than the potential of the second side opposite to the first side.

Description

Technical Field

[0001] The present invention relates to a conveying system including at least one carriage equipped with a magnet receiving an electromagnetic force from a coil group, and a conveying module and an inverter unit constituting the conveying system. Background Art

[0002] Generally, in a production line for assembling industrial products in which factory automation is achieved, a conveying system is used to convey components and the like between a plurality of workstations within or between production lines.

[0003] In a conveyor system, the conveyor line is divided into multiple control areas, with control devices installed in each control area, allowing the carriage to travel between the control areas. This type of conveyor system has excellent production efficiency and has been widely used in production lines in recent years.

[0004] Patent Document 1 below discloses a conveyor system in which linear motor fixtures are arranged at predetermined intervals in a track shape along a guide rail for a traveling trolley. The trolley is equipped with a movable side of the linear motor, allowing the trolley to circulate along the track. In this conveyor system, one inverter circuit is connected to one fixture, and a single direct current (DC) power supply is connected to multiple inverter circuits.

[0005] Patent Document 1: U.S. Patent No. 10367404 Summary of the Invention

[0006] In conventional conveyor systems, such as those described in Patent Document 1, workstation positions are fixed. Consequently, these systems often employ an operation profile in which the carriage is accelerated intermittently in one control zone, decelerated intermittently in another, and moved at a constant speed in yet another control zone.

[0007] In the aforementioned operating profile, where the timing of vehicle acceleration and deceleration differ, the regenerative energy generated in the deceleration control zone is immediately consumed as driving energy in the constant-speed vehicle control zone. Consequently, it is difficult to utilize the regenerative energy generated in the deceleration control zone as driving energy for acceleration in the acceleration control zone. Consequently, the system's power efficiency decreases, and a large system power capacity must be selected to match the maximum power required during vehicle acceleration.

[0008] The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to obtain a transmission system capable of improving the power efficiency of the system and suppressing an increase in the size of the system.

[0009] In order to solve the above-mentioned problems and achieve the purpose, the conveying system involved in the present invention has: at least two conveying modules, which have a coil group and an inverter unit that applies an AC voltage to the coil group; and at least one trolley, which carries a magnet that receives electromagnetic force from the coil group. Each inverter unit has an inverter circuit and a first diode. The inverter circuit is applied with a DC voltage output by a DC power supply and converts the DC voltage into an AC voltage. The first diode is configured to be connected between the DC power supply and the inverter circuit, and when the potential of the first side connected to the DC power supply is higher than the potential of the second side opposite to the first side, a positive current flows from the first side to the second side.

[0010] Effects of the Invention

[0011] According to the transmission system according to the present invention, there is an effect of being able to improve the power efficiency of the system and suppress the increase in size of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram showing a configuration example of a conveyance system common to the embodiments of the present invention.

[0013] Figure 2 It is a figure for explaining the subject of this invention.

[0014] Figure 3 This is a diagram showing a configuration example of a transport module according to the first embodiment.

[0015] Figure 4 This is a diagram for explaining the operation of the conveying system according to the first embodiment.

[0016] Figure 5 This is a diagram for explaining the operation before improvement in Implementation 2.

[0017] Figure 6 This is a diagram showing a configuration example of a transport module according to the second embodiment.

[0018] Figure 7 This is a diagram for explaining the second control method in the second embodiment.

[0019] Figure 8 This is a diagram showing a configuration example of a transport module according to the third embodiment. DETAILED DESCRIPTION

[0020] Hereinafter, the conveying system, conveying module and inverter unit involved in the embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, the embodiment described below is for illustration, and the scope of the present invention is not limited to the following embodiment. In addition, in the following description, multiple structural elements of the same type are represented by numbers with subscripts, but in the case of focusing on the description of each function of each structural element, the subscript marks are appropriately omitted. In addition, below, no distinction is made between physical connection and electrical connection, and the description is simply referred to as "connection". That is, the word "connection" includes both the case where structural elements are directly connected to each other and the case where structural elements are indirectly connected to each other via other structural elements.

[0021] Implementation method 1.

[0022] A conveyance system according to an embodiment of the present invention is a conveyance system including at least two conveyance modules and at least one cart to which a thrust is applied from each conveyance module. Figure 1 1 is a schematic diagram showing a configuration example of a common conveying system 1 in the embodiment of the present invention. Figure 1 As shown, there are a plurality of transport modules 100a to 100k, a plurality of carts 200a to

[0023] 200e, multiple workstations 300a, 300b, a DC power supply 400 and a controller 600.

[0024] DC power supply 400 is a power supply device or power supply circuit that outputs a predetermined DC voltage. DC power supply 400 may be of any configuration and voltage conversion method, as long as it can output the predetermined DC voltage. It is sufficient that there is one or more DC power supply 400 within conveyor system 1. In other words, there may be multiple DC power supplies 400.

[0025] The DC power supply 400 and the transport modules 100a to 100k are connected via a DC power supply line 500. The controller 600 and the plurality of transport modules 100 are configured to be able to communicate via a communication cable 700. Figure 1 In the embodiment, multiple transport modules 100 are connected in a daisy chain via a communication cable 700, but the present invention is not limited to this connection method. For example, the transport modules 100 can also be connected in a bus via a communication cable 700. Figure 1 In the embodiment, the controller 600 and the plurality of transport modules 100 are connected via a wired communication cable 700, but they may be connected wirelessly. In other words, the controller 600 and the plurality of transport modules 100 may be configured to be able to communicate via any communication means.

[0026] In addition, Figure 1In the embodiment, the plurality of conveying modules 100 are arranged in a straight line, but they can also be arranged in a curved line. That is, as long as the plurality of conveying modules 100 are connected to each other, a conveying path can be formed. Therefore, the shape of the conveying path formed by the plurality of conveying modules 100 can be a straight line or a closed loop. In addition, Figure 1 In the embodiment, the transport modules 100 are arranged without any gaps, but the present invention is not limited thereto. The transport modules 100 may be arranged with gaps therebetween.

[0027] The DC power supply 400 supplies driving power to the plurality of conveying modules 100. The controller 600 sends a command to the conveying module 100 and controls the flow of the conveying module 100. Figure 1 The current of the coil group (not shown) is controlled to apply thrust to the carriage 200 and control the movement of the carriage 200.

[0028] exist Figure 1 The travel direction 800 of the trolley 200 can be set for each trolley 200. Each trolley 200 stops at the conveyor module 100b and the conveyor module 100j of the workstation 300a and 300b, respectively. At the workstations 300a and 300b, transfer and processing of conveyable materials are performed. In other conveyor modules 100, the trolley 200 travels at a constant speed. The number of trolleys 200 that can be controlled at a single conveyor module 100 can be one or more.

[0029] Figure 2 It is a figure for explaining the subject of the present invention. Specifically, Figure 2 (a) shows the passage of the vehicle 200 through the transport module 100j over time. Figure 2 (b) shows the passage of the vehicle 200 in the transport module 100e over time. Figure 2 (c) shows the time course of the power consumption of the transport module 100j. Figure 2 (d) shows the time course of the power consumption of the transport module 100e. Figure 2 (e) shows the time elapse of the power supplied to the delivery modules 100j and 100e. Figure 1 As shown, it is considered that the DC voltage outputted from the DC power supply 400 is applied to the conveying modules 100 e and 100 j via the DC power supply line 500 .

[0030] right Figure 2 The action of Figure 2In the diagram, at the position of conveyor module 100j, the period from time t1 to time t2 is the period during which the passing vehicle 200 decelerates, defined as "vehicle deceleration period 1001." Similarly, at the position of conveyor module 100j, the period from time t5 to time t6 is the period during which the passing vehicle 200 accelerates, defined as "vehicle acceleration period 1002." Furthermore, at the position of conveyor module 100e, the period from time t1 to time t3 and from time t4 to time t5 is the period during which the passing vehicle 200 passes at a constant speed, defined as "vehicle constant speed passage period 1003" and "vehicle constant speed passage period 1004," respectively.

[0031] In the transport module 100j, the regenerative power 1101 generated during the vehicle deceleration period 1001 is stored in the transport module 100j. Figure 1 As described above, the DC power supply 400 is universalized, so the regenerative power 1101 is consumed as the driving power 1103 in the conveying module 100e during the period 1003 when the trolley passes at a constant speed, and is consumed as the driving power 1104 in the conveying module 100e during the period 1004 when the trolley passes at a constant speed. By this action, in the conveying module 100e, the regenerative power 1101 is consumed during the periods 1003 and 1004 when the trolley passes at a constant speed, so that the power supplied from the DC power supply 400 to the conveying module 100e via the DC power supply line 500 is as follows. Figure 2 (e) is zero. In the transport module 100j, during the vehicle constant speed passage periods 1003 and 1004, the vehicle 200 decelerates during the vehicle deceleration period 1001 from time t1 to time t2 and stops during the period from time t2 to time t5. Therefore, the power supplied to the transport module 100j is as follows: Figure 2 On the other hand, even if the regenerative power 1101 generated during the vehicle deceleration period 1001 can be used as the driving power 1103 and 1104, it is not guaranteed to be used as the driving power 1102 of the transport module 100j. Figure 1If the capacity of the capacitor (not shown) is not sufficiently large, the voltage of the DC power supply line 500 may rise due to the regenerative power 1101, resulting in a dangerous situation. In such a situation, it is of course necessary to further install a regenerative resistor to consume the regenerative power 1101, and it may not be possible to guarantee that it will be used as driving power 1103 and 1104. Therefore, during the trolley acceleration period 1002, it is necessary to set the system design based on the power supply from the DC power supply 400. Therefore, during the trolley acceleration period 1002, it is necessary to supply the conveying module 100j with the maximum peak power 1005. Therefore, it is necessary to increase the power supply capacity of the DC power supply 400 or increase the capacity of the capacitor mounted on the conveying module 100. As a result, the cost increase of the conveying system 1 becomes an issue.

[0032] In order to solve this problem, the conveying system 1 according to the first embodiment has Figure 3 The conveying module 100 is of the structure shown. Figure 3 : is a diagram showing a configuration example of the transport module 100 according to the first embodiment. Figure 3 2 conveying modules 100a, 100b and 1 trolley 200 are shown. The conveying module 100a has a coil group 102a and an inverter unit 103a, and the conveying module 100b has a coil group 102b and an inverter unit 103b. Figure 3 Two conveying modules 100a and 100b are shown in FIG. Figure 1 When the transport system is configured as the transport system 1 shown in FIG. 1 , each of the transport modules 100 a to 100 k includes a coil group 102 and an inverter unit 103 . Figure 1 The transport system 1 shown in the figure is an example of a transport system having 11 transport modules 100. The trolley 200 has a trolley frame 201 and a magnet 202 mounted on the trolley frame 201. The magnet 202 moves the trolley 200 by receiving electromagnetic force from the coil groups 102a and 102b. Figure 3 Although omitted, the conveying modules 100a and 100b have guide rails and position detection elements, and the trolley 200 has a position detection head. The guide rail is a track for the trolley 200 to travel, and is provided along the travel direction 800. The position detection head is a sensor for detecting the travel position of the trolley 200. Examples of position detection heads are optical or magnetic sensors, but other sensors may also be used. The position detection element is an element equipped with a position identifier read by the position detection head. Examples of position identifiers can be magnets, barcodes, or two-dimensional barcodes, but position identifiers other than these may also be used.

[0033] The inverter unit 103 is a power converter that converts the DC voltage output by the DC power supply 400 into an AC voltage based on instructions from the controller 600 and applies the converted AC voltage to the corresponding coil assembly 102. To achieve this function, the inverter unit 103a includes an inverter circuit 104a, a capacitor 105a, a drive control circuit 106a, a diode 107a, a processor 108a, and a communication interface (I / F) 109a. The inverter unit 103b is also configured similarly to the inverter unit 103a. Specifically, the inverter unit 103b includes an inverter circuit 104b, a capacitor 105b, a drive control circuit 106b, a diode 107b, a processor 108b, and a communication interface (I / F) 109b.

[0034] The diode 107 is configured such that its positive electrode is connected to the DC power supply 400 and its negative electrode is connected to the inverter circuit 104. Specifically, the diode 107 is connected between the DC power supply 400 and the inverter circuit 104, and when the potential of the first side connected to the DC power supply 400 is higher than the potential of the second side not connected to the DC power supply 400, that is, the second side opposite to the first side, a forward current flows from the first side to the second side. In this specification, the diode 107 may sometimes be referred to as the "first diode."

[0035] The inverter circuit 104 has upper and lower bridge arm switching elements connected in series. The conduction, i.e., the switching on and off, of these switching elements is controlled by the drive control circuit 106. A DC voltage output by the DC power supply 400 is applied to the inverter circuit 104. The inverter circuit 104 converts the DC voltage into an AC voltage and applies the converted AC voltage to each coil of the coil group 102. Figure 3 Only one branch consisting of the switching elements of the upper and lower bridge arms is shown in FIG, and the other two branches are omitted. Figure 3 The example in FIG. 1 shows a case where the coil group 102 is a three-phase coil, but the present invention is not limited thereto. The coil group 102 may also be a single-phase coil structure or a structure with four or more phases. In this case, a main circuit having a structure suitable for the coil group 102 is used as the inverter circuit 104.

[0036] The capacitor 105 is connected in parallel to both ends of the inverter circuit 104. The capacitor 105 is an electrolytic capacitor as shown in the figure, but may be a capacitor other than an electrolytic capacitor. The capacitor 105 smoothes and holds the DC voltage output from the DC power supply 400.

[0037] The processor 108 controls the drive control circuit 106 and performs necessary communication and information exchange with the controller 600 via the communication I / F 109. The processor 108 may also be called a microprocessor, microcomputer, microcomputer, CPU (Central Processing Unit), or DSP (Digital Signal Processor).

[0038] Figure 4 1 is a diagram for explaining the operation of the conveying system 1 according to the first embodiment. Figure 4 The action waveforms and their arrangement order shown in Figure 2 The same content as shown. In addition, Figure 4 The motion curve of the passing speed of the trolley 200 in the conveying modules 100b and 100j is Figure 2 The content shown is the same.

[0039] exist Figure 4 In, with Figure 2 The difference is the action waveform shown in (e). Specifically, Figure 4 The maximum peak power 1006 shown is Figure 2 The maximum peak power 1005 shown is suppressed to be lower in comparison.

[0040] In the transport module 100j, the regenerative power 1101 generated during the vehicle deceleration period 1001 flows into the transport module 100e without passing through the DC power supply line 500 due to the effect of the diode 107. Due to this effect, the regenerative power 1101 generated during the vehicle deceleration period 1001 is temporarily stored in the capacitor 105 within the transport module 100j. As a result, the transport module 100j can use the regenerative power 1101 stored in the capacitor 105 during the vehicle acceleration period 1002. Figure 2 Unlike the case of the transport module 100e, the transport module 100e cannot use the regenerative power 1101, so the driving power 1103 and 1104 for the vehicle 200 to travel at a constant speed are as follows: Figure 4 As shown in the lower part of the figure, the power is supplied from the DC power supply 400 or the capacitor 105 of the transport module 100e. On the other hand, the regenerative power 1101 stored in the capacitor 105 of the transport module 100j can be used during the vehicle acceleration period 1002 in the transport module 100j. As a result, in the transport module 100e, although the power supply from the DC power supply 400 is required, the maximum peak power 1006 can be used as the transport system 1. Figure 2The maximum peak power 1005 shown is lower than that shown in FIG. That is, the conveying system 1 according to Embodiment 1 does not need to increase the power capacity of the DC power supply 400 or the capacity of the capacitor 105 mounted in the conveying module 100 to match the maximum peak power, thereby suppressing an increase in the cost of the conveying system 1. Furthermore, the individual capacitors 105 do not necessarily need to be provided in the conveying modules 100j and 100e. Instead, the conveying module 100j can be configured to utilize the regenerative power 1001 during the vehicle acceleration period 1002 by utilizing the effect of the diodes 107 within the conveying modules 100j and 100e.

[0041] As described above, the conveying system and conveying module according to Embodiment 1 include at least two conveying modules that apply an AC voltage to a coil assembly. Each conveying module includes an inverter unit that applies the AC voltage to the coil assembly and imparts driving force to a cart equipped with a magnet that receives electromagnetic force from the coil assembly. Each inverter unit includes an inverter circuit having a first diode configured to allow a forward current to flow from the first side to the second side when the potential of the first side, connected to the DC power supply, is higher than the potential of the second side, opposite the first side. The provision of the first diode prevents the regenerative power generated by one conveying module from being used by other conveying modules sharing the DC power supply line. This allows the regenerative power generated by one conveying module to be used as driving power for the conveying module. Consequently, the maximum peak power, or the maximum driving power required by the DC power supply, can be reduced. This improves the system's power efficiency and prevents system size from increasing.

[0042] Furthermore, the transport system and transport module according to Embodiment 1 can reduce the maximum peak power required by the DC power supply, thereby reducing the power capacity of the DC power supply. This can reduce system costs. Furthermore, as previously described, the first diode is connected in the forward direction relative to the DC power supply. Therefore, if the DC power supply is connected to the transport module with the incorrect polarity, current flowing in the inverter circuit is blocked. This prevents damage to the transport module due to incorrect polarity connection of the DC power supply.

[0043] Implementation method 2.

[0044] Next, a description will be given of a transport system, a transport module, and an inverter unit according to Embodiment 2. The structures of the transport system 1 and the transport module 100 according to Embodiment 2 are the same as those of Embodiment 1, and their description will be omitted.

[0045] Figure 5 This is a diagram for explaining the operation before improvement in Implementation 2. Figure 2 and Figure 4This is the action curve when the conveyor module 100 responsible for accelerating the trolley 200 and the conveyor module 100 responsible for decelerating the trolley are the same. Figure 5 FIG shows an operation curve of the case where the conveying module 100 responsible for accelerating the trolley 200 and the conveying module 100 responsible for decelerating the trolley are different. Specifically, Figure 5 (a) shows the passage of the vehicle 200 in the transport module 100j over time. Figure 5 (b) shows the passage of the vehicle 200 in the transport module 100i over time. Figure 5 (c) shows the passage of the vehicle 200 in the transport module 100e over time. Figure 5 (d) shows the time course of the power consumption of the transport module 100j. Figure 5 (e) shows the time course of the power consumption of the transport module 100i. Figure 5 (f) shows the time course of the power consumption of the transport module 100e. Figure 5 (g) shows the time elapse of the power supplied to the transport modules 100i and 100e. Figure 5 In, about Figure 2 The same or equivalent contents are denoted by the same reference numerals.

[0046] exist Figure 5 In the example, conveyor module 100j is responsible for decelerating the cart 200, while conveyor module 100i is responsible for accelerating the cart 200. Furthermore, in conveyor module 100e, the cart 200 moves at a constant speed. That is, the cart 200 decelerates in conveyor module 100j, passes through conveyor module 100e at a constant speed, and accelerates in conveyor module 100i.

[0047] In the transport module 100j, the regenerative power 1101 generated during the deceleration period 1001 of the trolley is not reversely transferred to the DC power supply line 500 due to the action of the diode 107 in the transport module 100j, but is temporarily stored in the capacitor 105 in the transport module 100j and consumed by natural discharge or forced discharge. Therefore, the regenerative power 1101 generated by the transport module 100j cannot be used as the driving power 1102 of the transport module 100i or the driving power 1103 and 1104 of the transport module 100e. Figure 5 In the operation curve of , there is room for improvement in the power efficiency and power capacity of the transportation system 1.

[0048] Therefore, in the second embodiment, improvements are made in these aspects. Specifically, the conveying system 1 involved in the second embodiment has Figure 6 The conveying module 100 is of the structure shown. Figure 6 1 is a diagram showing a configuration example of a transport module 100 according to Embodiment 2. Figure 6 In, with Figure 3 Likewise, two transport modules 100a, 100b are shown, but in the Figure 1 When the transport system is configured as the transport system 1 shown in FIG. 1 , each of the transport modules 100 a to 100 k includes a coil group 102 and an inverter unit 103 . Figure 1 The conveying system 1 shown in the figure exemplifies a conveying system having 11 conveying modules 100. Figure 6 In, with Figure 3 The same or equivalent components of the transport module 100 according to the first embodiment are denoted by the same reference numerals, and overlapping contents are omitted as appropriate.

[0049] In the conveying module 100a, Figure 6 The structure shown is Figure 3 In comparison, the transmission module 100b is additionally provided with a switching element 110a, an opening and closing control circuit 111a, and a voltage detection circuit 112a. The transmission module 100b is similarly configured, and is additionally provided with a switching element 110b, an opening and closing control circuit 111b, and a voltage detection circuit 112b.

[0050] Switching element 110 is connected in parallel with both ends of diode 107. Alternatively, diode 107 and switching element 110 connected in parallel can be combined to form a MOSFET (Metal Oxide Semiconductor Field Effect Transistor). That is, diode 107 can utilize the body diode of a MOSFET. Switching control circuit 111 controls the conduction of switching element 110 based on instructions from processor 108. Voltage detection circuit 112 detects the voltage across capacitor 105 and outputs the detected value to processor 108. In this specification, switching element 110 may sometimes be referred to as the "first switching element."

[0051] Next, the use of Figure 6 Several control methods in the second embodiment of the conveying module 100 shown in FIG. Figure 5 shown.

[0052] First, the first control method is described. Figure 5 (a) to Figure 5 (c) shows the method of the motion curve of the vehicle 200.

[0053] In the transport module 100j, the regenerative power 1101 generated during the vehicle deceleration period 1001 is temporarily stored in the capacitor 105 in the transport module 100j. Based on the information of the vehicle 200 operation curve, the controller 600 sends a closing command for turning on the switch element 110 in the transport module 100j in accordance with the timing of the start of the vehicle acceleration period 1002 in the transport module 100i having the vehicle acceleration period 1002. For example, Figure 5 As shown, in the case where the transport module 100j is solely responsible for decelerating the vehicle 200 and the regenerative power 1101 stored in the capacitor 105 within the transport module 100j is not consumed during the vehicle 200's operation, the processor 108 within the transport module 100j controls the switching element 110 within the transport module 100j to conduct based on a closing command transmitted from the controller 600. The closing command transmitted from the controller 600 to the processor 108 within the transport module 100j is timed to coincide with the start of the vehicle acceleration period 1002. In this case, the transmission time between the controller 600 and the processor 108 within the transport module 100j naturally takes into account the processing time of the processor 108. Through this control, the regenerative power 1101 stored in the capacitor 105 within the transport module 100j can be utilized as the driving power 1102 for the transport module 100i. This reduces the maximum peak power 1006 required by the DC power supply 400, improves the system's power efficiency, and prevents system size from increasing.

[0054] Next, the second control method will be described. Figure 7 This is a diagram for explaining the second control method in Embodiment 2. The second control method is a method using the detection value of the voltage detection circuit 112 .

[0055] exist Figure 7 The waveforms of (a) to (g) are related to Figure 5 In addition, the action curves of the passing speed in the conveying modules 100e, 100i, and 100j are the same as Figure 5 On the other hand, in Figure 7 In Figure 1, between (e) and (f), the waveform of the capacitor voltage of the transmission module 100i is shown as (h). The capacitor voltage is the voltage of the capacitor 105. The electrical wiring connecting the DC power supply 400 and the inverter circuit 104 is generally called a "DC bus," and the capacitor 105 is often connected to the DC bus. Therefore, the capacitor voltage is sometimes referred to as the "bus voltage."

[0056] During the trolley acceleration period 1002, the trolley 200 is accelerated by the conveying module 100i, so the capacitor voltage of the capacitor 105 in the conveying module 100i drops sharply. This voltage drop is detected based on the detection value of the voltage detection circuit 112 in the conveying module 100i. When the capacitor voltage of the capacitor 105 in the conveying module 100i is lower than the voltage threshold 1007, the processor 108 in the conveying module 100i notifies the controller 600 of information indicating this situation, i.e., an excess notification. The voltage threshold 1007 is a pre-set lower limit value, i.e., a predetermined lower limit value. If the controller 600 receives the excess notification, it sends a closing instruction to the conveying module 100j responsible for the deceleration of the trolley 200 to close the switch element 110 in the conveying module 100j. Figure 7 In the case of the example, a closing command is sent to the transport module 100j. In the transport module 100j to which the closing command is sent, the regenerative power 1101 stored in the capacitor 105 in the transport module 100j is discharged by the potential difference and can be used as the driving power 1102 of the transport module 100i via the DC power supply line 500. Figure 5 The maximum peak power 1006 shown is lower than the maximum peak power 1006 required by the DC power supply 400 .

[0057] Furthermore, in the second control method described above, processor 108 transmits an exceeding notification when the capacitor voltage falls below voltage threshold 1007, but the present invention is not limited to this process. Processor 108 may also notify controller 600 of capacitor voltage information at regular intervals. In this case, controller 600 detects whether the capacitor voltage has fallen below voltage threshold 1007.

[0058] Furthermore, in the second control method, processor 108 transmits an overvoltage notification when the capacitor voltage falls below voltage threshold 1007. However, this notification may also be transmitted when the capacitor voltage exceeds a predetermined upper limit. As described above, overvoltage on capacitor 105, which may be caused by overregeneration or the like, can be prevented. This reduces the electrical stress on capacitor 105 and suppresses degradation of capacitor 105, thereby extending the life of capacitor 105.

[0059] As described above, according to the transmission system and transmission module of Embodiment 2, the inverter unit includes a first switching element connected in parallel with both ends of the first diode, and an on / off control circuit that controls the opening and closing of the first switching element. Furthermore, the inverter unit includes a voltage detection circuit that detects the bus voltage. The on / off control circuit controls the opening and closing of the first switching element when the bus voltage detected by the voltage detection circuit exceeds a predetermined upper limit or falls below a predetermined lower limit. This control allows regenerative power stored in capacitors within a transmission module to be utilized as driving power for other transmission modules, thereby reducing the maximum peak power required by the DC power supply. This improves the system's power efficiency and prevents system size from increasing. Furthermore, the power capacity of the DC power supply can be reduced, thereby reducing system costs.

[0060] Furthermore, the transmission system according to Embodiment 2 includes a controller that controls the operation of each inverter unit. This controller receives notifications from the inverter unit indicating that the detected bus voltage value has exceeded a predetermined upper limit or fallen below a predetermined lower limit, and controls the operation of the switching control circuit in the inverter unit. This control also enables the regenerative power stored in the capacitors within one transmission module to be utilized as driving power for other transmission modules, thereby reducing the maximum peak power required by the DC power supply. This improves the system's power efficiency and prevents system size from increasing.

[0061] Alternatively, instead of the above control, each inverter unit may notify the controller of the detected bus voltage value, and the controller may control the operation of the switching control circuit in at least one inverter unit based on the notified bus voltage detected value. This also achieves the above-mentioned effects.

[0062] Alternatively, instead of the above control, the controller may control the operation of the switching control circuit in at least one inverter unit based on the vehicle operation curve.

[0063] Implementation method 3.

[0064] Next, the conveyor system, conveyor module, and inverter unit according to Embodiment 3 are described. Embodiment 3 discloses a structure for suppressing surge current that may be generated when a DC voltage is applied to the conveyor module 100. The structures of the conveyor system 1 and conveyor module 100 according to Embodiment 3 are the same as those in Embodiment 1 or 2, and their description will be omitted.

[0065] Figure 8 3 is a diagram showing a configuration example of a transport module 100 according to Embodiment 3. Figure 8 In, with Figure 3 and Figure 6 Similarly, two transport modules 100a and 100b are shown, but Figure 1 When the transport system is configured as the transport system 1 shown in FIG. 1 , each of the transport modules 100 a to 100 k includes a coil group 102 and an inverter unit 103 . Figure 1 The conveying system 1 shown in the figure exemplifies a conveying system having 11 conveying modules 100. Figure 8 In, with Figure 6 The same or equivalent components of the transport module 100 according to the second embodiment are denoted by the same reference numerals, and overlapping contents are omitted as appropriate.

[0066] In the conveying module 100a, Figure 8 The structure shown is Figure 6 The transmission module 100b is similarly configured, but additionally includes an inrush current suppressing resistor 113a, a diode 114a, a switching element 115a, and an on / off control circuit 116a.

[0067] The inrush current suppression resistor 113 is connected in series with the switching element 110 to suppress the inrush current to the inverter circuit 104. Figure 8 In FIG, inrush current suppression resistor 113 is placed after switching element 110, but it can also be placed before switching element 110. That is, inrush current suppression resistor 113 can be connected in series with switching element 110 between DC power supply 400 and inverter circuit 104. Diode 114 and switching element 115 are connected in parallel with each other relative to inrush current suppression resistor 113. Diode 114 is connected in opposite directions relative to diode 107. That is, diode 114 is configured so that when the potential of the third side connected to DC power supply 400 is lower than the potential of the fourth side not connected to DC power supply 400, i.e., the fourth side opposite to the third side, a forward current flows from the fourth side to the third side. Furthermore, the parallel-connected diode 114 and switching element 115 can be combined to form a MOSFET. That is, diode 114 can utilize the body diode of the MOSFET. The switching control circuit 116 controls the conduction of switching element 115 according to instructions from processor 108. In this specification, the diode 114 may be referred to as a “second diode” and the switching element 115 may be referred to as a “second switching element”.

[0068] Next, the operation of the conveying system 1 according to Embodiment 3 will be described. First, when power begins to be supplied to the conveying module 100, the DC power supply 400 is controlled to be turned on. At this timing, the switching element 115 is set to an open state. When the switching element 115 is open, the inrush current flowing from the DC power supply 400 to the inverter unit 103 flows through the inrush current suppression resistor 113. This prevents a sudden inrush of current into the capacitor 105. This prevents capacitor 105 from malfunctioning due to inrush current. After a certain amount of time has passed since the inrush current began flowing, or when the capacitor voltage of the capacitor 105 exceeds a certain threshold, the processor 108 controls the switching element 115 to be closed. This allows the current supplied from the DC power supply 400 to the inverter unit 103 to flow through the switching element 115. The on-resistance of the switching element 115 is smaller than the resistance of the inrush current suppression resistor 113, thereby reducing power consumption in the inverter unit 103.

[0069] As described above, according to the transport system and transport module of Embodiment 3, the inverter unit includes an inrush current suppressing resistor that suppresses inrush current into the inverter circuit, a second switching element connected in parallel with the inrush current suppressing resistor, and a second diode connected in parallel with both the inrush current suppressing resistor and the second switching element. This configuration suppresses inrush current into the transport module at the time the DC power supply is turned on. This configuration, in addition to the advantages of Embodiments 1 and 2, can prevent capacitor failure caused by inrush current.

[0070] Furthermore, the configuration shown in the above embodiment is merely an example, and can be combined with other known technologies, the embodiments can be combined with each other, and part of the configuration can be omitted or changed without departing from the spirit of the invention.

[0071] Description of the label

[0072] 1 conveying system, 100, 100a to 100k conveying modules, 102, 102a, 102b coil groups, 103, 103a, 103b inverter units, 104, 104a, 104b inverter circuits, 105, 105a, 105b capacitors, 106, 106a, 106b drive control circuits, 107, 107a, 107b, 114, 114a, 114b diodes, 108, 108a, 108b processors, 109, 109a, 109b communication I / Fs, 110, 110a, 110b, 115, 115a, 115b switching elements, 111, 111a, 111b, 116, 116a, 116b opening and closing control circuit, 112, 112a, 112b voltage detection circuit, 113, 113a, 113b surge current suppression resistor, 200, 200a~200e trolleys, 201 trolley frame, 202 magnet, 300a, 300b workstations, 400 DC power supply, 500 DC power line, 600 controller, 700 communication cable, 800 direction of travel, 1001 during trolley deceleration, 1002 during trolley acceleration, 1003, 1004 during trolley constant speed passing, 1005, 1006 maximum peak power, 1007 voltage threshold, 1101 regenerative power, 1102, 1103, 1104 driving power.

Claims

1. A conveying system comprising: a plurality of conveying modules each having a coil group and an inverter unit for applying an AC voltage to the coil group; and at least one trolley equipped with a magnet receiving an electromagnetic force from the coil group. The conveying system is characterized in that Each of the inverter units has: an inverter circuit to which a DC voltage outputted from a common DC power source is applied and to which the DC voltage is converted into the AC voltage; a capacitor connected in parallel with the DC power supply side when viewed from the inverter circuit; a first diode connected between the DC power supply and the inverter circuit, and configured to allow a forward current to flow from a first side connected to the DC power supply toward a second side when a potential of the first side connected to the DC power supply is higher than a potential of a second side opposite to the first side; and a first switching element connected in parallel with both ends of the first diode; When one of the plurality of transport modules is set as the first transport module, The capacitor included in the first conveying module stores regenerative power generated when the vehicle decelerates and passes through the first conveying module. The first switching element included in the first transport module performs a closing operation when the regenerative power stored in the capacitor is used as driving power for a transport module different from the first transport module.

2. The conveying system according to claim 1, characterized in that Each of the inverter units includes: an opening and closing control circuit that controls the opening and closing of the first switching element; and a voltage detection circuit that detects the voltage of the electrical wiring connecting the first diode and the inverter circuit, that is, the bus voltage. Each of the switching control circuits controls the first switching element to be closed when the detection value of the bus voltage detected by the voltage detection circuit exceeds a predetermined upper limit value or falls below a predetermined lower limit value.

3. The conveying system according to claim 1, characterized in that The transmission system includes a controller for controlling the operation of each of the inverter units. The controller is configured to be able to communicate with each of the inverter units. Each of the inverter units includes: an opening and closing control circuit for controlling the opening and closing of the first switching element; and a voltage detection circuit for detecting a bus voltage, which is a voltage of an electrical wiring connecting the first diode and the inverter circuit, and notifying the controller of an excess notification indicating that a detection value of the bus voltage detected by the voltage detection circuit exceeds a predetermined upper limit value or falls below a predetermined lower limit value. When the controller is notified of the exceeding notification, it controls the operation of the switching control circuit in the inverter unit to close the first switching element.

4. The conveying system according to claim 1, characterized in that The transmission system includes a controller for controlling the operation of each of the inverter units. The controller is configured to be able to communicate with each of the inverter units. Each of the inverter units includes: an opening and closing control circuit that controls the opening and closing of the first switching element; and a voltage detection circuit that detects the voltage of the electrical wiring connecting the first diode and the inverter circuit, that is, the bus voltage, and notifies the controller of the detected value of the bus voltage. The controller controls the operation of the switching control circuit in at least one of the inverter units based on the detected value of the bus voltage to close the first switching element.

5. A conveying system comprising: at least two conveying modules each having a coil group and an inverter unit for applying an AC voltage to the coil group; and at least one trolley equipped with a magnet receiving an electromagnetic force from the coil group. The conveying system is characterized in that Each of the inverter units has: an inverter circuit to which a DC voltage outputted from a common DC power source is applied and to which the DC voltage is converted into the AC voltage; a first diode connected between the DC power supply and the inverter circuit, configured to allow a forward current to flow from the first side toward the second side when a potential of a first side connected to the DC power supply is higher than a potential of a second side opposite to the first side; a first switching element connected in parallel to both ends of the first diode; and an opening and closing control circuit for controlling the opening and closing of the first switching element, The transmission system includes a controller for controlling the operation of each of the inverter units. The controller is configured to be able to communicate with each of the inverter units. The controller controls the operation of the switching control circuit in at least one of the inverter units based on the operation curve of the vehicle. The movement curve of the carriage is the passage of the speed of the carriage through the conveying module over time.

6. The conveying system according to any one of claims 1 to 5, characterized in that The inverter unit has: an inrush current suppression resistor connected in series with the first switching element between the DC power supply and the inverter circuit to suppress an inrush current to the inverter circuit; a second switching element connected in parallel with the inrush current suppression resistor; and The second diode is configured to be connected in parallel with both the surge current suppression resistor and the second switching element, and when the potential of the third side connected to the DC power supply is lower than the potential of the fourth side opposite to the third side, a forward current flows from the fourth side toward the third side.

7. A conveying module comprising a coil group and an inverter unit for applying an AC voltage to the coil group to impart a driving force to a carriage equipped with a magnet receiving an electromagnetic force from the coil group. The conveying module is characterized in that The inverter unit and the inverter units of other transport modules are connected to a common DC power supply. The inverter unit has: an inverter circuit to which the DC voltage outputted by the DC power supply is applied and to which the DC voltage is converted into the AC voltage; a capacitor connected in parallel with the DC power supply side when viewed from the inverter circuit; a first diode connected between the DC power supply and the inverter unit, and configured to allow a forward current to flow from the first side toward the second side when a potential of a first side connected to the DC power supply is higher than a potential of a second side opposite to the first side; a first switching element connected in parallel to both ends of the first diode; and an opening and closing control circuit for controlling the opening and closing of the first switching element, The capacitor stores regenerative power generated when the vehicle decelerates and passes through. The opening and closing control circuit closes the first switching element when the regenerative electric power stored in the capacitor is used as driving power for another transmission module.

8. The conveying module according to claim 7, characterized in that The inverter unit has: an inrush current suppression resistor connected in series with the first switching element between the DC power supply and the inverter circuit to suppress an inrush current to the inverter circuit; a second switching element connected in parallel with the inrush current suppression resistor; and The second diode is configured to be connected in parallel with both the surge current suppression resistor and the second switching element, and when the potential of the third side connected to the DC power supply is lower than the potential of the fourth side opposite to the third side, a forward current flows from the fourth side toward the third side.

Images