Charging pile
By introducing conductive and test connections into the charging station, and using a short-circuit detection device to detect the electrical connection status between the pins and the current-carrying terminals, the problem of inefficient detection of the pin connections between printed circuit boards and electronic devices in existing technologies is solved, achieving fast and accurate detection results.
Patent Information
- Application Number
- CN202422969413.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2034-11-29
AI Technical Summary
In existing charging piles, it is impossible to efficiently and quickly detect whether the pins of printed circuit boards and electronic devices are electrically connected, resulting in inconvenient operation, high cost, and difficulty in popularizing them on production lines.
Introducing conductive and test connections into the charging pile, a short-circuit detection device detects the electrical connection status between the pin and the current-carrying terminal, and the electrical connection status of the conductive and test connections is used to determine the connection status between the pin and the circuit board, simplifying the detection process.
It enables rapid and accurate detection of the electrical connection status between pins and the circuit board, reduces detection costs, improves detection efficiency, and has been widely adopted on production lines.
Smart Images
Figure CN223729049U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of charging, in particular to a charging pile. BACKGROUND
[0002] In the charging pile, a printed circuit board (PCB) is connected with electronic devices, for example, the PCB of a power distribution unit is connected with a switch, one side of the PCB in the thickness direction can be provided with a through-flow terminal (for example, a copper substrate), and the through-flow terminal is insulated from the PCB. The pin of the switch penetrates through the PCB and the through-flow terminal, and is welded with the through-flow terminal and the PCB through solder (for example, tin). The through-flow terminal carries a large through-flow circuit of the switch, and the PCB carries a small through-flow circuit or a signal circuit of the switch.
[0003] When welding, the through-flow terminal is welded with the pin first, the solder melts between the pin and the through-flow terminal, and flows to between the pin and the PCB, and after the solder solidifies, the pin can be electrically connected with the through-flow terminal and the PCB respectively. Since it is not possible to observe whether the pin is connected with the PCB, it is necessary to detect whether the pin is electrically connected with the PCB. The existing detection method is inconvenient to operate, high in cost, and difficult to popularize on the production line. CONTENT OF THE UTILITY MODEL
[0004] The present application provides a charging pile to efficiently and quickly detect whether the pin between the circuit board and the electronic device is electrically connected.
[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:
[0006] The first aspect of the present application provides a charging pile, which comprises a circuit board, a through-flow terminal and an electronic device. The through-flow terminal is fixedly connected with the circuit board. The electronic device comprises one or more pins, and the pin penetrates through the circuit board and the through-flow terminal. Along the circumference of the pin, a conductive connection part is arranged between the through-flow terminal and the pin, and the conductive connection part is electrically connected with the pin and the through-flow terminal respectively. The surface of the circuit board is provided with a pin connection part and a test connection part, and the pin connection part is electrically connected with the test connection part. When the conductive connection part and the pin connection part are electrically connected, the test connection part is electrically connected with the through-flow terminal. When the conductive connection part and the pin connection part are not electrically connected, the test connection part and the through-flow terminal are not electrically connected.
[0007] In the charging pile given by the present application, the conductive connection part is electrically connected with the pin and the through-flow terminal respectively, the current transmitted by the pin can be transmitted to the through-flow terminal through the conductive connection part, and then transmitted to other devices through the through-flow terminal. Compared with the mode that the current transmitted by the pin is transmitted through the circuit board, the present application can reduce the heat generated when the current is transmitted through the circuit board, reduce the possibility of local overheating of the circuit board, and ensure the safety of the circuit board.
[0008] When the pin connecting portion and the conductive connecting portion are electrically connected, a part of the current transmitted by the pin can be transmitted to the pin connecting portion through the conductive connecting portion and transmitted to the test connecting portion through the pin connecting portion, in which case the test connecting portion is electrically connected with the through terminal. When the pin connecting portion and the conductive connecting portion are not electrically connected, the current of the conductive connecting portion cannot be transmitted to the pin connecting portion, in which case the pin connecting portion and the conductive connecting portion are open, i.e., the test connecting portion and the through terminal are open.
[0009] To detect whether the pin connecting portion and the conductive connecting portion are electrically connected, it can be achieved by detecting whether the test connecting portion and the through terminal are short-circuited. If the test connecting portion and the through terminal are short-circuited, the conductive connecting portion is electrically connected with the pin connecting portion, and if the test connecting portion and the through terminal are open, the conductive connecting portion and the pin connecting portion are not electrically connected.
[0010] For example, one detection portion (such as a detection probe) of an existing short-circuit detection device (such as a multimeter, an oscilloscope, etc.) is electrically connected with the test connecting portion, and the other detection portion is electrically connected with the through terminal. In this way, the test connecting portion and the through terminal are electrically connected by the short-circuit detection device. If the short-circuit detection device detects a short circuit, i.e., the test connecting portion, the pin connecting portion, the conductive connecting portion, the through terminal are sequentially electrically connected, and are connected into a loop by the short-circuit detection device, in which case the conductive connecting portion is electrically connected with the pin connecting portion, i.e., the pin is electrically connected with the circuit board. If the short-circuit detection device detects an open circuit, i.e., the test connecting portion, the pin connecting portion, the conductive connecting portion, the through terminal and the short-circuit detection device are not connected into a loop, since the test connecting portion and the pin connecting portion are electrically connected, the conductive connecting portion and the through terminal are electrically connected, and the test connecting portion and the through terminal are electrically connected through the short-circuit detection device, thus the short-circuit detection device detects an open circuit, which indicates that the conductive connecting portion and the pin connecting portion are not electrically connected, i.e., the pin and the circuit board are not electrically connected.
[0011] The test connecting portion is arranged on the surface of the circuit board, and the through terminal is arranged outside the circuit board, which can facilitate the short-circuit detection device to be connected with the test connecting portion and the through terminal respectively, and the operation is simple and convenient. In addition, through the short-circuit detection mode, whether the pin connecting portion and the conductive connecting portion are electrically connected, i.e., whether the circuit board and the pin are electrically connected, can be quickly detected, and the detection precision and efficiency are high, which can be popularized on the production line and has a low cost.
[0012] In addition, the electrical connection effect of the conductive connecting portion and the through terminal can be quickly judged by the short circuit detection. Since the pin connecting portion is located on the surface of the circuit board, the conductive connecting portion is electrically connected with the pin connecting portion, and it can be understood that the size of the conductive connecting portion in the thickness direction of the circuit board is greater than the size of the through terminal in the thickness direction of the circuit board, that is, the contact area of the conductive connecting portion and the through terminal is increased, which indicates that the electrical connection effect of the pin and the through terminal is good. If the conductive connecting portion and the pin connecting portion are not electrically connected, the contact area of the conductive connecting portion and the through terminal is small, and the electrical connection effect of the pin and the through terminal is poor.
[0013] In an optional embodiment, the inside of the circuit board comprises a first metal layer, and the first metal layer is electrically connected with the test connecting portion and the pin connecting portion respectively.
[0014] By the first metal layer, the test connecting portion and the pin connecting portion can be electrically connected. Since the first metal layer is located in the inside of the circuit board, that is, the first metal layer can be arranged by using the internal space of the circuit board, the space utilization of the circuit board is improved. Moreover, compared with the connection of the test connecting portion and the pin connecting portion on the outside of the circuit board, the first metal layer is arranged in the inside of the circuit board, which saves space and reduces the influence of the external environment on the first metal layer, that is, reduces the influence of the external environment on the electrical connection between the test connecting portion and the pin connecting portion, and ensures the connection reliability between the test connecting portion and the pin connecting portion.
[0015] In an optional embodiment, the circuit board comprises a first through hole, and the first through hole penetrates the circuit board along the thickness direction of the circuit board. The first through hole is located between the test connecting portion and the pin connecting portion, the inner wall of the first through hole is provided with a second metal layer, the second metal layer is electrically connected with the test connecting portion, and the second metal layer is also electrically connected with the first metal layer.
[0016] By the second metal layer, the test connecting portion and the first metal layer can be electrically connected. By using the first through hole and the second metal layer arranged in the first through hole, on the one hand, the length of the first metal layer can be reduced, and the cost and weight of the circuit board can be reduced. On the other hand, the test connecting portion can be located on one side of the through hole around the through terminal, so that the test connecting portion corresponding to the through terminal can be quickly identified by the operator, and the short circuit detection between the test connecting portion and the through terminal can be performed, and the detection efficiency is improved.
[0017] In an optional embodiment, the surface of the circuit board is provided with a third metal layer, the third metal layer is arranged around the first through hole, and the third metal layer is electrically connected with the test connecting portion and the second metal layer respectively.
[0018] The third metal layer can facilitate the electrical connection between the test connecting portion and the second metal layer. That is, the test connecting portion does not need to extend into the first through hole, and can be electrically connected with the second metal layer by connecting the third metal layer on the surface of the circuit board. In addition, since the test connecting portion and the third metal layer are both arranged on the surface of the circuit board, the electrical connection between the test connecting portion and the third metal layer is facilitated, for example, the test connecting portion is adhered to the surface of the circuit board and is welded with the third metal layer, which is convenient and easy to operate.
[0019] In some examples, the third metal layer and the second metal layer are integrally formed, which is convenient to process and can save assembly procedures.
[0020] In an optional embodiment, the circuit board includes a second through hole for the pin to pass through, the second through hole penetrates the circuit board in the thickness direction of the circuit board, an inner wall of the second through hole is provided with a fourth metal layer, and the fourth metal layer is electrically connected with the first metal layer. The pin connecting portion is arranged around the second through hole, and the pin connecting portion is electrically connected with the fourth metal layer.
[0021] The fourth metal layer can electrically connect the pin connecting portion and the first metal layer. The second through hole and the fourth metal layer arranged in the second through hole can reduce the length of the first metal layer, and reduce the cost and weight of the circuit board. In addition, the fourth metal layer electrically connects the first metal layer and the pin connecting portion, so that the first metal layer can be electrically connected with the fourth metal layer at different positions in the thickness direction of the circuit board, which is more flexible.
[0022] The pin connecting portion is arranged around the second through hole, so that the conductive connecting portion can be electrically connected with the pin connecting portion at any position in the circumferential direction of the second through hole, which can facilitate the electrical connection between the conductive connecting portion and the pin connecting portion, and reduce or avoid the possibility that the electrical connection between the conductive connecting portion and the pin connecting portion is affected by the uneven distribution of the conductive connecting portion on the outer periphery of the pin.
[0023] In some examples, the fourth metal layer and the pin connecting portion are integrally formed, which is convenient to process and can save assembly procedures.
[0024] In an optional embodiment, the internal part of the circuit board includes a fifth metal layer, the fifth metal layer is electrically connected with the fourth metal layer, and the fifth metal layer has a smaller current carrying capacity than the current carrying terminal.
[0025] The fifth metal layer has a smaller current carrying capacity than the current carrying terminal, which means that the maximum current value that the fifth metal layer can withstand and safely transmit is smaller than the maximum current value that the current carrying terminal can withstand and safely transmit.
[0026] For example, in some examples, the fifth metal layer has a smaller cross-sectional area than the throughflow terminal under the same condition, and the fifth metal layer has a smaller throughflow capacity than the throughflow terminal.
[0027] In some other examples, the fifth metal layer has a smaller conductivity than the throughflow terminal under the same condition, and the fifth metal layer has a smaller throughflow capacity than the throughflow terminal.
[0028] Since the fifth metal layer has a smaller throughflow capacity than the throughflow terminal, a larger current transmitted by the pin of the electronic device can be transmitted to the throughflow terminal through the conductive connection, and then transmitted to the corresponding device through the throughflow terminal. A smaller current or signal transmitted by the pin can be transmitted to the pin connection through the conductive connection, and then transmitted to the fifth metal layer through the fourth metal layer, and finally transmitted to the corresponding device through the fifth metal layer. Compared with the way that the current transmitted by the pin of the electronic device is transmitted through the internal metal layer of the circuit board, such as the fifth metal layer, the arrangement of the fifth metal layer and the throughflow terminal can reduce the heat generated when the internal metal layer of the circuit board transmits the current, reduce the possibility of local overheating of the circuit board, and ensure the safety of the circuit board.
[0029] In some examples, the throughflow terminal can be a copper substrate. Copper has good conductivity and low resistivity, so current can be effectively transmitted through the copper substrate, reducing energy loss. In addition, copper has better heat conduction effect, and the heat of the circuit board can also be quickly conducted out through the copper substrate, thereby improving the heat dissipation efficiency of the circuit board and preventing heat from accumulating on the circuit board.
[0030] In an optional embodiment, the throughflow terminal includes a third through hole for the pin to pass through, the third through hole penetrating the throughflow terminal along the thickness direction of the circuit board, and the third through hole has a larger aperture than the second through hole.
[0031] It can be understood that the third through hole has a larger aperture and the second through hole has a smaller aperture. The larger aperture of the third through hole can accommodate more solder, not only ensuring that the solder is distributed more evenly in the third through hole, i.e., the conductive connection is distributed more evenly in the third through hole, ensuring the electrical connection reliability of the pin and the throughflow terminal, but also enabling the solder to flow smoothly and evenly to the second through hole, ensuring the electrical connection reliability of the conductive connection and the pin connection.
[0032] In an optional embodiment, the throughflow terminal is fixedly connected with the circuit board through an insulating structure, and the insulating structure is located between the throughflow terminal and the circuit board. The insulating structure is arranged opposite to a part of the pin connection in the thickness direction of the circuit board.
[0033] The insulation structure can insulate the through-flow terminal from the surface of the circuit board, reduce or avoid the possibility of short circuit between the through-flow terminal and the circuit board due to direct contact between the through-flow terminal and the circuit board, and improve safety performance.
[0034] The insulation structure is arranged opposite to a part of the pin connecting portion in the thickness direction of the circuit board, and can be understood as that the part of the pin connecting portion is located between the insulation structure and the circuit board, which can prevent the conductive connecting portion from directly contacting the surface of the circuit board, reduce or avoid the possibility of short circuit between the conductive connecting portion and the circuit board due to direct contact between the conductive connecting portion and the circuit board, and further improve safety performance.
[0035] In some examples, the insulation structure includes an insulation adhesive layer, and the thickness of the insulation adhesive layer is 50 μm to 200 μm.
[0036] During connection, the insulation adhesive (such as polypropylene adhesive) is applied on the surface of the circuit board for connecting the through-flow terminal, or on the surface of the through-flow terminal for connecting the circuit board, and then the two are tightly pressed together, and the insulation adhesive forms an insulation adhesive layer after curing.
[0037] The thickness of the insulation adhesive layer is 50 μm to 200 μm, which can ensure the insulation between the through-flow terminal and the circuit board while reducing overflow of the insulation adhesive.
[0038] In an optional embodiment, the test connecting portion is arranged on the surface of the circuit board facing the through-flow terminal.
[0039] In this way, the short circuit detection device can be connected to the test connecting portion and the through-flow terminal to facilitate short circuit detection between the test connecting portion and the through-flow terminal, that is, short circuit detection between the pin connecting portion and the conductive connecting portion.
[0040] In an optional embodiment, the pin includes a plurality of pins, the number of test connecting portions is the same as and corresponds to the number of pins, and the plurality of test connecting portions are located on the same side of the circuit board.
[0041] It can be understood that whether each pin is electrically connected to the circuit board can be detected by short circuit detection between the test connecting portion and the through-flow terminal. During short circuit detection, a short circuit detection device can simultaneously perform short circuit detection between a plurality of test connecting portions and a plurality of through-flow terminals, in other words, a short circuit detection device can simultaneously detect whether a plurality of pins are electrically connected to the circuit board, which has high detection efficiency and can be detected on the production line, thereby helping the operator to quickly identify the pins that are not electrically connected to the circuit board.
[0042] In an alternative embodiment, the electronic device comprises a switch unit. The charging pile further comprises a power conversion unit and a charging interface. The charging interface is configured to connect the charging gun. The power conversion unit is configured to output direct current. The switch unit is electrically connected to the power conversion unit and the charging interface, and is configured to disconnect or conduct the electrical connection between the power conversion unit and the charging interface.
[0043] The power conversion unit is configured to convert the form of current, such as converting alternating current into direct current, or converting direct current into direct current with another voltage value. When the switch unit conducts the electrical connection between the power conversion unit and the charging interface, the converted direct current of the power conversion unit can be transmitted to the charging interface, and the charging interface transmits the converted direct current to the charging gun. The charging gun is configured to connect with the device to be charged, such as a vehicle, and then charge the device to be charged. When the switch unit disconnects the electrical connection between the power conversion unit and the charging interface, the converted direct current of the power conversion unit cannot be transmitted to the charging interface.
[0044] In some examples, the charging interface comprises a plurality of charging interfaces, each of which is configured to connect a charging gun. The switch unit also comprises a plurality of switch units, each of which is electrically connected to a charging interface and a power conversion unit, and is configured to disconnect or conduct the electrical connection between the charging interface and the power conversion unit. Through the plurality of switch units, the direct current output by the power conversion unit can be distributed and transmitted to the corresponding charging interface.
[0045] In this example, the power conversion unit can comprise a plurality of power conversion units, each of which is electrically connected to a plurality of charging interfaces. Each charging interface is electrically connected to a plurality of power conversion units, and the plurality of power conversion units electrically connected to each charging interface are the same. Any power conversion unit is electrically connected to a charging interface through a switch unit, and the switch unit is configured to disconnect or conduct the electrical connection between the power conversion unit and the charging interface. BRIEF DESCRIPTION OF DRAWINGS
[0046] Figure 1 A structural schematic diagram of a charging pile provided by an embodiment of the present application;
[0047] Figure 2 A connection schematic diagram of a power conversion unit and a charging interface in a charging pile provided by an embodiment of the present application;
[0048] Figure 3 A partial structural schematic diagram of a charging pile provided by an embodiment of the present application, in which the pin connection part is electrically connected to the conductive connection part;
[0049] Figure 4 Another partial structural schematic diagram of a charging pile provided by an embodiment of the present application, in which the pin connection part is not electrically connected to the conductive connection part;
[0050] Figure 5A short circuit detection connection schematic diagram of a partial structure of a charging pile provided by an embodiment of the present application is provided.
[0051] Figure 6 Another partial structure schematic diagram of a charging pile provided by an embodiment of the present application is provided, and the test connection part is located between the first through hole and the pin connection part.
[0052] Figure 7 Another partial structure schematic diagram of a charging pile provided by an embodiment of the present application is provided, and the fifth metal layer is shown.
[0053] Figure 8 Another partial structure schematic diagram of a charging pile provided by an embodiment of the present application is provided, and two test connection parts are shown.
[0054] Reference signs:
[0055] 100 - charging pile; 10 - power distribution unit; 20 - charging gun; 30 - power conversion unit; 40 - charging interface;
[0056] 1 - circuit board; 11 - test connection part; 12 - pin connection part; 131 - first metal layer; 132 - second metal layer; 133 - third metal layer; 134 - fourth metal layer; 135 - fifth metal layer; 14 - first through hole; 15 - second through hole;
[0057] 2 - through terminal; 21 - third through hole; 3 - insulating structure;
[0058] 4 - electronic device; 41 - switch unit; 411 - pin; 5 - conductive connection part;
[0059] 200 - short circuit detection device. DETAILED DESCRIPTION
[0060] The technical solutions in the embodiments of the present application will be described below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments.
[0061] In the present application, unless otherwise explicitly specified and limited, the orientation or position relationship indicated by the terms "up", "down", "front", "back", "left", "right" and the like can include but not limited to the orientation defined by the relative placement of the components in the drawings, wherein these directional terms can be a relative concept, which are used for relative description and clarification, and can be changed accordingly according to the change of the placement of the components in the drawings, and cannot be understood as a limitation on the present application.
[0062] In the present application, the terms "first", "second", etc. are only used for descriptive purposes and are not to be construed as indicating or implying relative importance or an indicated number of technical features. Therefore, the features defined with "first", "second", etc. can explicitly or implicitly include one or more of the features.
[0063] In the present application, the meaning of "multiple" is two or more, unless otherwise explicitly specified and limited.
[0064] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. In addition, when describing pipelines or channels, "connecting" and "connection" used in the present application have the meaning of conducting. The specific meaning should be understood in combination with the context.
[0065] In addition, in the present application, the words "exemplary" or "for example" are used to mean serving as an example, instance, or illustration. Any embodiment or design solution described as "exemplary" or "for example" in the present application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of "exemplary" or "for example" is intended to present relevant concepts in a specific manner.
[0066] In the drawings of the embodiments of the present application, the entity structures of components, assemblies, etc. are represented by guide lines; the hollow structures of openings, holes, spaces, cavities, etc. are represented by guide lines with arrows.
[0067] The charging pile provided by the embodiments of the present application. The charging pile is used for connecting with a device to be charged, such as a vehicle, to charge the device to be charged. Wherein, the charging pile can be an integrated charging pile, or a split charging pile.
[0068] Figure 1 An exemplary structure schematic diagram of a charging pile 100 is shown. Referring to Figure 1 , the charging pile 100 includes a power distribution unit 10, a plurality of power conversion units 30, a plurality of charging interfaces 40 and a plurality of charging guns 20. Each charging interface 40 is used to connect one charging gun 20.
[0069] The power conversion units 30 are used to convert the current and output direct current. The direct current converted by each power conversion unit 30 is transmitted to the input end of the power distribution unit 10. The power distribution unit 10 distributes the current and outputs the current to the plurality of charging interfaces 40 through the output end, and the charging interfaces are used to connect the charging gun 20 to supply power to the charging gun 20. The charging gun 20 is used to connect with the device to be charged, such as a vehicle, and then charge the device to be charged.
[0070] In Figure 1 In the example charging pile 100, the power distribution unit 10 includes a control module 50 and a plurality of switch units 41. The control module 50 is electrically connected with the plurality of switch units 41. In this way, the closing and opening of the plurality of switch units 41 is controlled by the control module 50 to distribute the direct current input by the plurality of power conversion units 30 and enable the distributed current to be transmitted to the corresponding charging interface.
[0071] In other examples, the power conversion unit 30 can include one, and the direct current converted by the power conversion unit 30 is transmitted to the power distribution unit 10, and the power distribution unit 10 distributes the current to the plurality of charging interfaces 40. The number of power conversion units 30 is not specially limited in the embodiments of the present application, and can be selectively designed by those skilled in the art according to actual needs.
[0072] In this example, the power conversion unit 30 can be used to convert alternating current into direct current. In other examples, the power conversion unit 30 can also be used to convert direct current into direct current with different voltages. The specific form of the power conversion unit 30 is not specially limited in the present application.
[0073] The working principles, structures and connection modes of the power distribution unit 10, the power conversion unit 30, the charging interface 40 and the charging gun 20 are well known to those skilled in the art, and will not be described here.
[0074] Figure 2 An example is shown in a connection diagram of the power conversion unit 30 and the charging interface 40 in the above charging pile 100. Referring to Figure 2 The plurality of power conversion units 30 are connected to the input end of the power distribution unit 10. Each power conversion unit 30 is electrically connected with the plurality of charging interfaces 40, each charging interface 40 is electrically connected with the plurality of power conversion units 30, and the plurality of power conversion units 30 electrically connected with each charging interface 40 are the same. Any power conversion unit 30 is electrically connected with the charging interface 40 through the switch unit 41, and the switch unit 41 is used to disconnect or conduct the electrical connection between the power conversion unit 30 and the charging interface 40.
[0075] For example, the plurality of power conversion units 30 includes a first power conversion unit, a second power conversion unit, and a third power conversion unit. The plurality of charging interfaces includes a first charging interface, a second charging interface, and a third charging interface. The plurality of switch units includes a first switch unit a, a first switch unit b, a first switch unit c, a second switch unit a, a second switch unit b, a second switch unit c, a third switch unit a, a third switch unit b, and a third switch unit c.
[0076] The first power conversion unit is electrically connected with the first charging interface through the first switch unit a. The first power conversion unit is electrically connected with the second charging interface through the second switch unit a. The first power conversion unit is electrically connected with the third charging interface through the third switch unit a.
[0077] The first switch unit a is closed, and the electrical connection between the first power conversion unit and the first charging interface is conducted. The first switch unit a is opened, and no electrical connection is established between the first power conversion unit and the first charging interface.
[0078] The second switch unit a is closed, and the electrical connection between the first power conversion unit and the second charging interface is conducted. The second switch unit a is opened, and no electrical connection is established between the first power conversion unit and the second charging interface.
[0079] The third switch unit a is closed, and the electrical connection between the first power conversion unit and the third charging interface is conducted. The third switch unit a is opened, and no electrical connection is established between the first power conversion unit and the third charging interface.
[0080] Similarly, the second power conversion unit is electrically connected with the first charging interface through the first switch unit b. The second power conversion unit is electrically connected with the second charging interface through the second switch unit b. The second power conversion unit is electrically connected with the third charging interface through the third switch unit b.
[0081] The third power conversion unit is electrically connected with the first charging interface through the first switch unit c. The third power conversion unit is electrically connected with the second charging interface through the second switch unit c. The third power conversion unit is electrically connected with the third charging interface through the third switch unit c.
[0082] The connection mode of the second power conversion unit with the three charging interfaces 40 and the connection mode of the third power conversion unit with the three charging interfaces 40 are the same as the connection mode of the first power conversion unit with the three charging interfaces 40, which will not be described here.
[0083] When one or more of the first switch units a, b and c are turned on, the first charging interface can supply power to the charging gun connected to the first charging interface; when all the first switch units a, b and c are turned off, the first charging interface cannot supply power to the charging gun connected to the first charging interface.
[0084] When one or more of the second switch units a, b and c are turned on, the second charging interface can supply power to the charging gun connected to the second charging interface; when all the second switch units a, b and c are turned off, the second charging interface cannot supply power to the charging gun connected to the second charging interface.
[0085] When one or more of the third switch units a, b and c are turned on, the third charging interface can supply power to the charging gun connected to the third charging interface; when all the third switch units a, b and c are turned off, the third charging interface cannot supply power to the charging gun connected to the third charging interface.
[0086] The above is an example in which the power conversion unit 30 includes three units. In other embodiments of the present application, the power conversion unit 30 can also include other numbers of units, such as four units, eight units, etc. Those skilled in the art can selectively design according to actual needs.
[0087] Figure 3 An exemplary partial structure schematic diagram of a charging pile is shown. Referring to Figure 3 The power distribution unit 10 of the charging pile includes a circuit board 1 and a through-flow terminal 2. The through-flow terminal 2 is fixedly connected to the circuit board 1 through an insulation structure 3, and the insulation structure 3 is located between the through-flow terminal 2 and the circuit board 1.
[0088] The insulation structure 3 can insulate the surface of the through-flow terminal 2 facing the circuit board 1 from the circuit board 1, thereby reducing or avoiding the possibility of short circuit between the through-flow terminal 2 and the circuit board 1 due to direct contact between the circuit board 1 and the through-flow terminal 2, and the safety performance of the circuit board 1 and the through-flow terminal 2 is higher.
[0089] In some examples, the insulation structure 3 includes an insulation adhesive layer 31. When connected, the insulation adhesive (such as polypropylene adhesive) is applied on the surface of the circuit board 1 for connecting the through-flow terminal 2, or on the surface of the through-flow terminal 2 for connecting the circuit board 1, and then the two are tightly pressed together, and the insulation adhesive forms the insulation adhesive layer 31 after curing.
[0090] The thickness of the insulating adhesive layer 31 is 50-200 μm, which can ensure the insulation of the throughflow terminal 2 and the circuit board 1 and reduce glue overflow. The thickness of the insulating adhesive layer 31 can be any value between 50-200 μm, such as 50 μm, 80 μm, 120 μm, 170 μm or 200 μm, and the application does not make specific limitations on the material and thickness of the insulating adhesive layer 31.
[0091] Referring to Figure 3 , the power distribution unit 10 further comprises an electronic device 4, which comprises one or more pins 411, which can be pins of any electronic device, such as the pins 411 of the switch unit 41 shown in Figure 1 and Figure 2 . The pins 411 pass through the circuit board 1 and the throughflow terminal 2. And along the circumference of the pins 411, the conductive connection part 5 is arranged between the throughflow terminal 2 and the pins 411, and the conductive connection part 5 is electrically connected with the throughflow terminal 2 and the pins 411 respectively. In this way, the current transmitted by the pins 411 can be transmitted to the throughflow terminal 2 through the conductive connection part 5, and then transmitted to other devices through the throughflow terminal 2. Compared with the mode of transmitting current through the circuit board 1, the mode of transmitting current through the throughflow terminal 2 can reduce the heat generated when the circuit board 1 transmits current, reduce the possibility of local overheating of the circuit board 1, and ensure the safety of the circuit board 1.
[0092] In some examples, the conductive connection part is a metal layer, such as a metal layer formed after the solidification of metal solder (such as tin). The application does not make special limitations on the specific material of the conductive connection part.
[0093] The surface of the circuit board 1 is provided with a test connection part 11 and a pin connection part 12, and the inside of the circuit board 1 is provided with a first metal layer 131, which is electrically connected with the pin connection part 12 and the test connection part 11 respectively.
[0094] Since the first metal layer 131 is located inside the circuit board 1, i.e., the first metal layer 131 can be arranged in the internal space of the circuit board 1, the space utilization rate of the circuit board 1 is improved. Moreover, compared with the connection of the test connection part 11 and the pin connection part 12 on the outside of the circuit board 1, the first metal layer 131 is arranged inside the circuit board 1, which saves space and reduces the influence of the external environment on the first metal layer 131, i.e., reduces the influence of the external environment on the electrical connection between the test connection part 11 and the pin connection part 12, and ensures the connection reliability between the test connection part 11 and the pin connection part 12.
[0095] In other examples, the first metal layer 131 can also be arranged on the surface of the circuit board 1, and those skilled in the art can selectively design the position of the first metal layer 131 according to actual needs.
[0096] Referring to Figure 3 Since the pin connecting portion 12 and the test connecting portion 11 are electrically connected, when the pin connecting portion 12 is electrically connected with the conductive connecting portion 5, part of the current transmitted by the pin 411 can be transmitted to the pin connecting portion 12 through the conductive connecting portion 5 and transmitted to the test connecting portion 11 through the pin connecting portion 12, in which case the test connecting portion 11 is electrically connected with the through terminal 2.
[0097] In this example, the insulating structure 3 can be arranged opposite to part of the pin connecting portion 12 in the thickness direction of the circuit board 1, that is, part of the pin connecting portion 12 is located between the insulating structure 3 and the circuit board 1, so that the conductive connecting portion 5 can be prevented from directly contacting the surface of the circuit board 1, and the possibility of short circuit between the conductive connecting portion 5 and the circuit board 1 due to direct contact between the conductive connecting portion 5 and the circuit board 1 is reduced or avoided, further improving the safety performance of the circuit board 1.
[0098] Figure 4 An example shows a schematic diagram of a partial structure of a charging pile, in which the pin connecting portion 12 is not electrically connected with the conductive connecting portion 5. Referring to Figure 4 , the pin connecting portion 12 is not electrically connected with the conductive connecting portion 5. Therefore, the current of the conductive connecting portion 5 cannot be transmitted to the pin connecting portion 12. And since the insulating structure 3 is arranged between the through terminal 2 and the circuit board 1, that is, the surface of the through terminal 2 and the circuit board 1 is insulated, in this case, the pin connecting portion 12 is open with the conductive connecting portion 5, that is, the test connecting portion 11 is open with the through terminal 2.
[0099] In order to detect whether the pin connecting portion 12 and the conductive connecting portion 5 are electrically connected, referring to Figure 3 and Figure 4 Since the pin 411 is electrically connected with the conductive connecting portion 5, and the conductive connecting portion 5 is electrically connected with the through terminal 2, the test connecting portion 11 is electrically connected with the pin connecting portion 12 through the first metal layer 131. Therefore, whether the pin connecting portion 12 and the conductive connecting portion 5 are electrically connected can be detected by detecting whether the test connecting portion 11 and the through terminal 2 are short-circuited. If the test connecting portion 11 and the through terminal 2 are detected to be short-circuited, the conductive connecting portion 5 and the pin connecting portion 12 are electrically connected. If the test connecting portion 11 and the through terminal 2 are detected to be open, the conductive connecting portion 5 and the pin connecting portion 12 are not electrically connected.
[0100] In some examples, the test connecting portion 11 can be a copper connecting portion, or a connecting portion of other materials, and the material of the test connecting portion 11 is not specially limited in the embodiments of the application.
[0101] Referring to Figure 4The through terminal 2 includes a third through hole 21 through which the pin 411 passes, the third through hole 21 penetrating the through terminal 2 along the thickness direction of the circuit board 1, and the aperture of the third through hole 21 is larger than the aperture of the second through hole 15.
[0102] It can be understood that the aperture of the third through hole 21 is larger, and the aperture of the second through hole 15 is smaller. The larger aperture of the third through hole 21 can accommodate more solder, not only can make the solder melt more evenly in the third through hole 21, that is, the conductive connection part 5 is more evenly distributed in the third through hole 21, to ensure the electrical connection reliability of the pin 411 and the through terminal 2, but also can make the solder flow smoothly and evenly to the second through hole 15, to ensure the electrical connection reliability of the conductive connection part 5 and the pin connection part 12.
[0103] Figure 5 An exemplary short circuit detection connection diagram of the local structure of the charging pile is given. Referring to Figure 5 , one detection part (such as a detection probe) of the short circuit detection device 200 (such as a multimeter, an oscilloscope, or other detection equipment) is electrically connected with the test connection part 11, and the other detection part is electrically connected with the through terminal 2. In this way, the test connection part 11 and the through terminal 2 are electrically connected by the short circuit detection device 200. If the short circuit detection device 200 detects a short circuit, that is, the test connection part 11, the pin connection part 12, the conductive connection part 5, and the through terminal 2 are sequentially electrically connected, and are connected into a loop by the short circuit detection device 200, in this case, the conductive connection part 5 and the pin connection part 12 are electrically connected, that is, the pin 411 and the circuit board 1 are electrically connected. If the short circuit detection device 200 detects an open circuit, that is, the test connection part 11, the pin connection part 12, the conductive connection part 5, the through terminal 2, and the short circuit detection device 200 are not connected into a loop, since the test connection part 11 and the pin connection part 12 are electrically connected, the conductive connection part 5 and the through terminal 2 are electrically connected, and the test connection part 11 and the through terminal 2 are electrically connected through the short circuit detection device 200, thus, the short circuit detection device 200 detects an open circuit, indicating that the conductive connection part 5 and the pin connection part 12 are not electrically connected, that is, the pin 411 and the circuit board 1 are not electrically connected. Through this detection method, whether the pin connection part 12 and the conductive connection part 5 are electrically connected, that is, whether the circuit board 1 and the pin 411 are electrically connected, can be quickly detected, the detection accuracy and efficiency are high, and the method can be popularized on the production line and has a relatively low cost.
[0104] In this example, the test connection part 11 is arranged on the surface of the circuit board 1, and the through terminal 2 is arranged on the outside of the circuit board 1, which can facilitate the short circuit detection device 200 to be connected with the test connection part 11 and the through terminal 2 respectively, and the operation is simple and convenient.
[0105] In addition, taking the metal layer formed after the soldering of the conductive connecting part 5 as an example. During soldering, the solder is usually inserted into the gap between the pin 411 and the throughflow terminal 2, and soldering is performed between the pin 411 and the throughflow terminal 2 on the side of the throughflow terminal 2. By Figure 5 The short-circuit detection mode can quickly determine the electrical connection effect of the conductive connecting part 5 and the throughflow terminal 2. Since the pin connecting part 12 is located on the surface of the circuit board 1, the conductive connecting part 5 is electrically connected with the pin connecting part 12. It can be understood that the size of the conductive connecting part 5 in the thickness direction of the circuit board 1 is greater than the size of the throughflow terminal 2 in the thickness direction of the circuit board 1, which increases the contact area of the conductive connecting part 5 and the throughflow terminal 2. Therefore, the electrical connection between the pin 411 and the throughflow terminal 2 is good. If the conductive connecting part 5 is not electrically connected with the pin connecting part 12, the contact area of the conductive connecting part 5 and the throughflow terminal 2 is small, and the electrical connection between the pin 411 and the throughflow terminal 2 is poor.
[0106] In this example, the structure, working principle and connection mode of the short-circuit detection device 200 are known to those skilled in the art, and will not be described here.
[0107] In some examples, the throughflow terminal 2 can be a copper substrate. The heat dissipation efficiency of the circuit board 1 can be improved by using a copper substrate, and the heat accumulation on the circuit board 1 can be reduced or avoided, thereby preventing the circuit board 1 from overheating. In addition, copper has good electrical conductivity and low resistivity, so that the current can be effectively transmitted through the copper substrate, thereby reducing energy loss.
[0108] In other embodiments, the throughflow terminal 2 can also be an aluminum substrate, an iron substrate, etc. The material of the throughflow terminal 2 is not limited in the present application.
[0109] In some examples, the conductive connecting part 5 is a tin conductive connecting part, which is formed by soldering the throughflow terminal 2 and the pin 411. Tin has good electrical conductivity, so that when the surface of the tin conductive connecting part facing the circuit board 1 exceeds the surface of the throughflow terminal 2 facing the circuit board 1, the electrical connection between the pin 411 and the throughflow terminal 2, and the electrical connection between the pin 411 and the circuit board 1 can be stable and reliable, thereby ensuring effective transmission of current. In addition, tin has good weldability, and can form a stable oxide protective layer at high temperature, thereby preventing oxidation and corrosion. Therefore, the conductive connecting part 5 is stable and reliable, and the current conduction is smooth.
[0110] Referring to Figure 5The test connecting portion 11 is arranged on the surface of the circuit board 1 facing the throughflow terminal 2, so that the short circuit detection device 200 can be connected to the test connecting portion 11 and the throughflow terminal 2 to facilitate the short circuit detection between the test connecting portion 11 and the throughflow terminal 2, i.e., the short circuit detection between the pin connecting portion 12 and the conductive connecting portion 5.
[0111] In some examples, referring to Figure 5 The circuit board 1 comprises a first through hole 14 penetrating the circuit board 1 along the thickness direction of the circuit board 1. The first through hole 14 is located between the test connecting portion 11 and the pin connecting portion 12, and the inner wall of the first through hole 14 is provided with a second metal layer 132 electrically connected to the test connecting portion 11 and the first metal layer 131.
[0112] The second metal layer 132 can electrically connect the test connecting portion 11 and the first metal layer 131. By using the first through hole 14 and the second metal layer 132 arranged in the first through hole 14, on the one hand, the length of the first metal layer 131 can be reduced, and the cost and weight of the circuit board 1 can be reduced. On the other hand, the test connecting portion 11 can be located on the side of the through hole around the throughflow terminal 2, so that the operator can quickly identify the test connecting portion 11 corresponding to the throughflow terminal 2 and perform the short circuit detection between the test connecting portion 11 and the throughflow terminal 2, thereby improving the detection efficiency.
[0113] In addition, the surface of the circuit board 1 is provided with a third metal layer 133 surrounding the first through hole 14, and the third metal layer 133 is electrically connected to the test connecting portion 11 and the second metal layer 132, respectively.
[0114] The third metal layer 133 can facilitate the electrical connection between the test connecting portion 11 and the second metal layer 132. That is, the test connecting portion 11 does not need to extend into the first through hole 14, and only needs to be connected to the third metal layer 133 on the surface of the circuit board 1 to realize the electrical connection between the test connecting portion 11 and the second metal layer 132. In addition, since the test connecting portion 11 and the third metal layer 133 are arranged on the surface of the circuit board 1, the electrical connection between the test connecting portion 11 and the third metal layer 133 is also facilitated, for example, the test connecting portion 11 is arranged on the surface of the circuit board 1 and is welded with the third metal layer 133, which is convenient and easy to operate.
[0115] In some examples, the third metal layer 133 and the second metal layer 132 are integrally formed, which is convenient to process and can save processing and assembly procedures.
[0116] Figure 6 An exemplary partial structure schematic diagram of a charging pile is shown. Referring to Figure 6The test connection part 11 is located between the first through hole 14 and the pin connection part 12. The pin connection part 12 is electrically connected in sequence through the third metal layer 133, the second metal layer 132, the first metal layer 131, and the pin connection part 12.
[0117] With reference to Figure 6 The circuit board 1 includes a second through hole 15 for the pin to pass through, the second through hole 15 penetrates the circuit board 1 along the thickness direction of the circuit board 1. The inner wall of the second through hole 15 is provided with a fourth metal layer 134, and the fourth metal layer 134 is electrically connected with the first metal layer 131. The pin connection part 12 is arranged around the second through hole 15, and the pin connection part 12 is electrically connected with the fourth metal layer 134. The pin connection part 12 is electrically connected in sequence through the third metal layer 133, the second metal layer 132, the first metal layer 131, the fourth metal layer 134, and the pin connection part 12.
[0118] Through the fourth metal layer 134, the pin connection part 12 and the first metal layer 131 can be electrically connected. By using the second through hole 15 and the fourth metal layer 134 arranged in the second through hole 15, the length of the first metal layer 131 can be reduced, and the cost and weight of the circuit board 1 can be reduced. In addition, the fourth metal layer 134 electrically connects the first metal layer 131 and the pin connection part 12, so that the first metal layer 131 can be electrically connected with the fourth metal layer 134 at different positions in the thickness direction of the circuit board 1, and the flexibility is higher.
[0119] The pin connection part 12 is arranged around the second through hole 15, so that the conductive connection part 5 can be electrically connected with the pin connection part 12 at any position in the circumferential direction of the second through hole 15, which can facilitate the electrical connection between the conductive connection part 5 and the pin connection part 12, and reduce or avoid the possibility that the electrical connection between the conductive connection part 5 and the pin connection part 12 is affected by the uneven distribution of the conductive connection part 12 on the outer periphery of the pin 411.
[0120] In some examples, the fourth metal layer 134 and the pin connection part 12 are integrally formed, which is convenient to process and can save processing and assembly processes.
[0121] Figure 7 An exemplary partial structure schematic diagram of a charging pile is shown. With reference to Figure 7 The inside of the circuit board 1 includes a fifth metal layer 135, and the fifth metal layer 135 is electrically connected with the fourth metal layer 134.
[0122] In some examples, the fifth metal layer 135 has a smaller current carrying capacity than the current carrying terminal 2. It can be understood that the maximum current value that the fifth metal layer 135 can withstand and safely transmit is smaller than the maximum current value that the current carrying terminal 2 can withstand and safely transmit.
[0123] For example, in some examples, the cross-sectional area of the fifth metal layer is smaller than the cross-sectional area of the throughflow terminal under the same condition, and the throughflow capacity of the fifth metal layer is smaller than the throughflow capacity of the throughflow terminal.
[0124] For example, in some examples, the electrical conductivity of the fifth metal layer is smaller than the electrical conductivity of the throughflow terminal under the same condition, and the throughflow capacity of the fifth metal layer is smaller than the throughflow capacity of the throughflow terminal.
[0125] Since the throughflow capacity of the fifth metal layer 135 is smaller than the throughflow capacity of the throughflow terminal 2, a larger current transmitted by the pin 411 of the electronic device 4 can be transmitted to the throughflow terminal 2 through the conductive connection 5, and then transmitted to the corresponding device through the throughflow terminal 2. A smaller current or signal flow transmitted by the pin 411 can be transmitted to the pin connection 12 through the conductive connection 5, then transmitted to the fifth metal layer 135 through the fourth metal layer 134, and finally transmitted to the corresponding device through the fifth metal layer 135. Compared with the mode that the current transmitted by the pin 411 of the electronic device 4 is transmitted through the metal layer inside the circuit board 1, such as the fifth metal layer 135, the arrangement of the throughflow terminal 2 can reduce the heat generated when the metal layer inside the circuit board 1 transmits the current, reduce the possibility of local overheating of the circuit board 1, and ensure the safety of the circuit board 1.
[0126] Figure 8 An exemplary partial structure schematic diagram of a charging pile is shown. Referring to Figure 8 The pin 411 of the electronic device 4 includes two, and the pin connection also includes two. The number of test connections 11 is the same as and one-to-one corresponds to the number of pins 411, that is, two pin connections 12, two test connections 11, and two throughflow terminals. Each pin 411 is provided with a test connection 11, a pin connection 12, and a throughflow terminal.
[0127] When detecting whether each pin 411 is electrically connected with the circuit board 1, the detection can be performed through the short circuit test between the test connection 11 corresponding to the pin 411 and the throughflow terminal 2.
[0128] Among them, the two test connections 11 are located on the same side of the circuit board 1, so that when the short circuit detection is performed, the connection of the two pins 411 with the circuit board 1 can be detected at the same time through one short circuit detection device, which is high in detection efficiency and can be detected in the whole production line, thereby helping the user to quickly identify the pin 411 which is not connected with the conductive connection 5 and the pin connection 12, thereby facilitating the user to focus on in the subsequent throughflow aging test stage.
[0129] In other examples, the circuit board 1 can also include other numbers of test connections 11, and the number of test connections 11 is not limited in the embodiments of the present application, and can be selected according to actual needs by those skilled in the art.
[0130] In the above examples, the materials of the first metal layer, the second metal layer, the third metal layer, the fourth metal layer and the fifth metal layer can be various, for example, the first metal layer, the second metal layer, the third metal layer, the fourth metal layer and the fifth metal layer are all made of copper, and the present application does not make special limitations thereon, and those skilled in the art can adaptively select according to actual needs.
[0131] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
Claims
1. A charging pile, characterized in that, The circuit board comprises: a through terminal fixedly connected with the circuit board; an electronic device comprising one or more pins penetrating through the circuit board and the through terminal; a conductive connecting part provided between the through terminal and the pin in the circumferential direction of the pin, and electrically connected with the pin and the through terminal respectively; a surface of the circuit board is provided with a pin connecting part and a test connecting part, and the pin connecting part and the test connecting part are electrically connected; when the conductive connecting part is electrically connected with the pin connecting part, the test connecting part is electrically connected with the through terminal; when the conductive connecting part is not electrically connected with the pin connecting part, the test connecting part is not electrically connected with the through terminal. The inside of the circuit board comprises a first metal layer electrically connected with the test connecting part and the pin connecting part respectively.
2. The charging post of claim 1, wherein, The circuit board comprises a first through hole penetrating through the circuit board in the thickness direction of the circuit board; the first through hole is located between the test connecting part and the pin connecting part, and an inner wall of the first through hole is provided with a second metal layer electrically connected with the test connecting part and the first metal layer.
3. The charging post of claim 2, wherein, A surface of the circuit board is provided with a third metal layer surrounding the first through hole, and the third metal layer is electrically connected with the test connecting part and the second metal layer respectively.
4. The charging post of claim 3, wherein, The circuit board comprises a second through hole for the pin to penetrate through, and the second through hole penetrates through the circuit board in the thickness direction of the circuit board; an inner wall of the second through hole is provided with a fourth metal layer electrically connected with the first metal layer; 5. The charging post according to any one of claims 2-4, characterized in that, The pin connecting part surrounds the second through hole, and the pin connecting part is electrically connected with the fourth metal layer. The inside of the circuit board comprises a fifth metal layer electrically connected with the fourth metal layer, and the fifth metal layer has a through flow capacity smaller than that of the through terminal.
6. The charging post of claim 5, wherein, The through terminal comprises a third through hole for the pin to penetrate through, and the third through hole penetrates through the through terminal in the thickness direction of the circuit board, and the third through hole has a larger aperture than the second through hole.
7. The charging post of claim 5, wherein, The through terminal is fixedly connected with the circuit board through an insulating structure between the through terminal and the circuit board; 8. The charging post of any one of claims 1-4, wherein, The insulating structure is oppositely arranged with a part of the pin connecting part in the thickness direction of the circuit board. The test connecting part is arranged on the surface of the circuit board facing the through terminal.
9. The charging post of any one of claims 1-4, wherein, The pin comprises a plurality of pins, and the number of the test connecting parts is the same as and one-to-one corresponding to the number of the pins, and the plurality of test connecting parts are located on the same side of the circuit board.
10. The charging post of any one of claims 1-4, wherein, The electronic device comprises a switch unit; 11. The charging post of any one of claims 1-4, wherein, The charging pile further comprises a power conversion unit and a charging interface; The charging interface is used for connecting a charging gun; The power conversion unit is used for outputting direct current; The switch unit is electrically connected with the power conversion unit and the charging interface, and is used for disconnecting or conducting the electrical connection between the power conversion unit and the charging interface.