controller

Abstract

To improve a resistance noise performance of a controller.SOLUTION: A controller 1 includes: a metal housing 2; and a power supply input part 3 to which an AC current is input from an external power supply. The controller 1 generates a driving current output to the external part by converting the AC current supplied from the power supply input part 3 to a DC current. The power supply input part 3 comprises: a power supply input terminal base 4 arranged into the housing 2; and a noise filter into which the AC current is input via the power supply input terminal base 4. The housing 2 comprises: a main frame 20 in which the power supply input part 3 is installed; and a frame ground terminal base 10 to which protective earth wires PE1 to PE5 of the power supply input part 3 and earth wires GL1 and GL2 of an AC power supply are connected. The frame ground terminal base 10 and the main frame 20 are made from the same metal, and both of base material surfaces where a plating coated film is not formed are welded in a contact state.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a controller having a metal housing. [Background technology]

[0002] Patent Document 1 describes a controller for controlling a robot that houses various units such as a control circuit board, a drive circuit board, a communication interface board, a drive voltage generation board, and a power supply circuit board inside a metal housing.

[0003] The controller of Patent Document 1 has an external power connector and a circuit protector on the front panel of the housing that switches between supplying and cutting off 200V AC current input from the external power connector, and inside the housing are power supply system units such as a drive voltage generation board and a power circuit board that are equipped with a noise filter that removes noise from the AC current and a DC / AC conversion circuit that converts the noise-removed AC current into DC current. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5803213 Summary of the Invention [Problem to be solved by the invention]

[0005] To suppress noise carried on the AC current supplied from an external power source, controllers employ a structure that uses a metal housing as a frame ground to allow noise to escape. For example, a frame ground terminal block is provided on the housing by fastening a metal terminal block component with screws to a metal plate fixed to the housing frame. Each unit in the power supply system is connected to the frame ground via a frame ground wire routed between the unit and the frame ground terminal block.

[0006] However, when providing a frame ground terminal block on a housing, noise resistance may be insufficient depending on the configuration of the frame ground terminal block. For example, if the contact resistance between the terminal block components and the metal panel on the housing side is high, noise and surges cannot be completely dissipated.

[0007] In view of the above problems, an object of the present invention is to improve the noise resistance performance of a controller. [Means for solving the problem]

[0008] In order to solve the above problem, the controller of the present invention has a metal housing, a power supply input unit that receives AC current from an external power supply, a DC / AC conversion circuit that converts the AC current supplied from the power supply input unit into DC current, and a drive current generation unit that generates a drive current to be output to the outside based on the DC current supplied from the DC / AC conversion circuit, wherein the power supply input unit includes a power supply input terminal block disposed within the housing and at least one noise filter to which AC current is input via the power supply input terminal block, and the housing includes a main frame on which the power supply input unit is installed and a frame ground terminal block to which a protective earth wire of the power supply input unit is connected, and the frame ground terminal block and the main frame are made of the same metal and are welded together with their base surfaces, on which no plating film is formed, in contact.

[0009] According to the present invention, among the metal members that make up the housing of the controller, a member having a large capacity is A frame ground terminal block made of the same metal as the mainframe is welded to a mainframe. The welding is performed with the base surfaces, which are not plated, in contact with each other. By directly fastening the frame ground terminal block to the mainframe in this manner, ground resistance can be reduced compared to when other components are interposed between the mainframe and the frame ground terminal block. Furthermore, by abutting the base surfaces, which are not plated, against each other, contact resistance between the mainframe and the frame ground terminal block can be reduced. Reducing ground resistance facilitates noise escape from the frame ground terminal block, thereby improving noise resistance. Furthermore, fastening by welding ensures reliable contact, eliminating variations in contact resistance due to variations in screw tightening torque when fastening with screws. Therefore, variations in noise resistance performance can be suppressed. This allows the noise filter to be simplified while still achieving the required noise resistance, thereby reducing noise filter costs. Furthermore, reducing the number of screw fastening holes allows for the frame ground terminal block to be smaller, reducing component costs, and eliminating the risk of mis-disassembly.

[0010] In the present invention, the mainframe preferably has a power input unit installation surface on which the power input unit is installed, and the frame ground terminal block is preferably disposed on the power input unit installation surface. In this way, the power input unit and the frame ground terminal block are disposed on the same surface. This improves the workability when routing and connecting the frame ground wire of the power input unit to the frame ground terminal block.

[0011] In the present invention, the main frame preferably includes a bottom plate of the housing and a frame-shaped housing frame connected to the outer edge of the bottom plate, the power input unit installation surface being provided on the bottom plate, and the frame ground terminal block being located on the outer edge of the bottom plate. This allows easy access to the frame ground terminal block by removing an outer panel fixed to the housing frame, thereby improving the workability when connecting a protective earth wire to the frame ground terminal block.

[0012] In the present invention, the frame ground terminal block preferably includes a fixed plate that abuts against the bottom plate and an inclined plate that extends along the outer edge of the bottom plate, the protective earth wire being fixed to the inclined plate, and the inclined plate inclines away from the bottom plate as it approaches the power input port from the outer edge. This configuration allows the fixing surface (i.e., the inclined plate) for fixing the protective earth wire to be visible when the frame ground terminal block placed on the bottom plate is viewed from diagonally above. This improves the ease of connecting the protective earth wire.

[0013] In the present invention, the power input terminal block is preferably disposed at the end of the power input section on the frame ground terminal block side. This allows the power input terminal block and the frame ground terminal block to be closer to each other. This makes it easier to connect the protective earth wire of the power input terminal block to the frame ground terminal block. Furthermore, since the power input terminal block and the frame ground terminal block can be disposed together at the end of the power input section, wiring work can be performed efficiently.

[0014] In the present invention, it is preferable that the power supply cable drawn into the housing includes a power supply line that supplies AC current from an AC power source and a ground line that is connected to the ground terminal of the AC power source, the power supply line being connected to the power input terminal block, and the ground line being connected to the frame ground terminal block. In this way, by connecting the ground line of the AC power source directly to the frame ground terminal block, the frame ground can be effectively grounded. Therefore, by concentrating the protective ground wires of the power input section at the frame ground terminal block, the power input section can be effectively grounded via the frame ground terminal block.

[0015] In the present invention, the power input unit preferably includes a molded case circuit breaker disposed in the current supply path connecting the power input terminal block and the noise filter, and the protective earth wire of the power input terminal block and the protective earth wire of the noise filter are connected to the frame ground terminal block. In this manner, many of the protective earth wires of the power input unit are concentrated at the frame ground terminal block. Therefore, by connecting the AC power supply's earth wire to the frame ground terminal block, many of the electronic elements constituting the power input unit are earthed via the frame ground terminal block, improving noise resistance. Furthermore, the noise filter can be simplified, resulting in cost reduction.

[0016] In this case, the power input section preferably includes a surge protector disposed in the current supply path connecting the power input terminal block and the noise filter, and the protective earth wire of the surge protector is preferably connected directly to the frame ground terminal block or to the frame ground terminal block via the power input terminal block. In this way, when a surge protector is added, the surge protector is also grounded via the frame ground terminal block, just like other electronic elements. This improves noise resistance.

[0017] In the present invention, it is preferable that the power input section includes a distribution connector that distributes the AC current that has passed through the noise filter, and that the protective earth wire of the power input terminal block, the protective earth wire of the noise filter, and the protective earth wire of the distribution connector are connected to the frame ground terminal block. In this way, noise in the AC current supplied from the distribution connector can be reduced, further improving noise resistance.

[0018] In the present invention, the power supply input unit comprises a first power supply input unit that supplies an AC current for generating a drive current, and a second power supply input unit that supplies an AC current for generating a control current of a voltage different from the drive current, the first power supply input unit comprises a first wiring circuit breaker and at least one of the noise filters, the second power supply input unit comprises a second wiring circuit breaker, at least one of the noise filters, and a distribution connector, and the frame ground terminal block is connected to a protective earth wire of the power supply input terminal block, a protective earth wire of each noise filter provided in the first power supply input unit, a protective earth wire of each noise filter provided in the second power supply input unit, and a protective earth wire of the distribution connector, and it is preferable that the protective earth wire of the first surge protector and the protective earth wire of the second surge protector are connected directly to the frame ground terminal block or connected to the frame ground terminal block via the power supply input terminal block. In this way, the electronic elements constituting the first power supply input section and the electronic elements constituting the second power supply input section are each grounded via the frame ground terminal block, thereby reducing noise in the control current and drive current. [Effects of the Invention]

[0019] According to the present invention, a frame ground terminal block made of the same metal as the main frame is welded to the main frame, which is the largest metal member constituting the controller housing. At this time, welding is performed with the base surfaces not coated with plating abutting against each other. By fixing the frame ground terminal block directly to the main frame in this way, it is possible to reduce the ground resistance compared to when other members are interposed between the main frame and the frame ground terminal block. Furthermore, by abutting the base surfaces not coated with plating against each other, it is possible to reduce the contact resistance between the main frame and the frame ground terminal block. By reducing the ground resistance, noise can be more easily released from the frame ground terminal block, improving noise resistance. Furthermore, fixing by welding ensures a secure connection. This allows for accurate contact, eliminating the variation in contact resistance caused by variations in screw tightening torque when fixing with screws. This reduces variations in noise resistance performance. This allows the noise filter to be simplified while still achieving the required noise resistance performance, thereby reducing noise filter costs. Furthermore, the reduction in screw fixing holes allows for the miniaturization of the frame ground terminal block and reduction in component costs, while also eliminating the risk of incorrect disassembly of the frame ground terminal block. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a perspective view of the appearance of a controller to which the present invention is applied; [Figure 2] FIG. 2 is a partial perspective view of the controller with the interface panel and side panels removed. [Figure 3] 2 is a cross-sectional view of the controller (a cross-sectional view taken along line AA in FIG. 1) and a partially enlarged view thereof. [Figure 4] FIG. 2 is a block diagram schematically illustrating a power supply input unit. [Figure 5] FIG. 2 is an enlarged perspective view of the main frame and the power input unit as viewed from the front side. [Figure 6]FIG. 2 is a perspective view of a portion of the main frame to which a frame ground terminal block is fixed. [Figure 7] 1A and 1B are perspective views of a frame ground terminal block as viewed obliquely from above and below. [Figure 8] 10A and 10B are noise waveform diagrams of a noise terminal voltage test in the controller of the present embodiment and a conventional controller. [Figure 9] FIG. 10 is a perspective view showing a connection mode of a protective earth wire when a frame terminal block of a modified example is used. DETAILED DESCRIPTION OF THE INVENTION

[0021] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A controller according to an embodiment of the present invention will be described below with reference to the drawings. A controller 1 according to this embodiment is a device that supplies power to a robot (manipulator) equipped with an actuator such as a motor.

[0022] Fig. 1 is an external perspective view of a controller 1 to which the present invention is applied. Fig. 2 is a partial perspective view of the controller 1 with an interface panel 21A and a side plate 24 removed. Fig. 3 is a cross-sectional view of the controller 1 (a cross-sectional view taken along line AA in Fig. 1) and a partially enlarged view thereof.

[0023] In this specification, the three directions X, Y, and Z are mutually orthogonal. For convenience, in this specification, the Z direction is defined as the up-down direction of the controller 1. The Z1 direction is downward, and the Z2 direction is upward. The X direction is the front-to-rear direction of the controller 1. The X1 direction is forward, and the X2 direction is backward. The Y direction is the width direction of the controller 1. The Y1 direction and the Y2 direction are one side and the other side of the Y direction. Note that, in actual use of the controller 1, the Z direction does not have to coincide with the up-down direction (vertical direction).

[0024] (Overall composition) As shown in FIGS. 1 to 3, the controller 1 includes a metal housing 2. The housing 2 is a rectangular parallelepiped and includes a front surface 2a facing the X1 direction, a back surface 2b facing the X2 direction, a side surface 2c facing the Y1 direction, a side surface 2d facing the Y2 direction, a bottom surface 2e facing the Z1 direction, and a top surface 2f facing the Z2 direction. In this embodiment, the components that make up the housing 2 include three interface panels 21A, 21B, and 21C arranged on the front surface 2a, a back plate 22 arranged on the back surface 2b, a side plate 23 arranged on the side surface 2c on the Y1 side, a side plate 24 arranged on the side surface 2d on the Y2 side, a top plate 25 arranged on the top surface 2f, and a main frame 20.

[0025] The main frame 20 is made up of a bottom plate 26 disposed on the bottom surface 2e and a rectangular block connected to the outer edge of the bottom plate 26. The interface panels 21A, 21B, and 21C, the back panel 22, the side panels 23 and 24, and the top panel 25 are external panels of the housing 2, and are detachably fixed to the housing frame 27.

[0026] As shown in FIG. 2, the housing frame 27 includes a rectangular front frame 27A, side frames 27B, and a top frame 27C. Interface panels 21A, 21B, and 21B are fixed to the front frame 27A. A top plate 25 is fixed to the top frame 27C. A side plate 24 on the Y2 side is fixed to the side frame 27B. The front frame 27A and the side frames 27B rise in the Z2 direction from the outer edge of the bottom plate 26 and are connected to the outer edge of the top frame 27C. The housing frame 27 also includes a back frame to which the back plate 22 is fixed, and a side frame to which the side plate 23 on the Y1 side is fixed (neither is shown).

[0027] The controller 1 includes a power supply input unit 3 to which AC current is input from an external power supply. As shown in FIGS. 2 and 3, the power supply input unit 3 is disposed inside an interface panel 21A disposed at the Y2-side end of the front surface of the housing 2 in the internal space of the housing 2. As shown in FIGS. 1 and 3, two power supply cables 40 of the external AC power supply are drawn into the housing 2 from sleeves 28 attached to the interface panel 21A.

[0028] The controller 1 includes a DC / AC conversion circuit (not shown) that converts a portion of the AC current supplied from the power supply input unit 3 into a DC current of a predetermined voltage, and a drive current generation unit (not shown) that generates a drive current to be output to the outside based on the DC current supplied from the DC / AC conversion circuit. The circuit boards and electronic elements that make up the DC / AC conversion circuit and the drive current generation unit are disposed inside the housing 2. The drive current generation unit is connected to an external output connector 29 (see FIG. 1) provided on the interface panel 21C. When a connector on the manipulator side is connected to the external output connector 29, a drive current is supplied to the manipulator.

[0029] The controller 1 also includes a communication board (not shown), a control circuit board (not shown), and a cooling fan 6, which are arranged inside the housing 2. A plurality of external connection connectors 30, which are arranged at the end of the communication board, are placed in holes provided in the interface panel 21B. A plurality of fans 6 are arranged inside the back panel 22. As shown in FIG. 2, one of the plurality of fans 6 is arranged behind the power input unit 3 (on the X2 side).

[0030] (Power input section) Fig. 4 is a block diagram showing a schematic diagram of the power input unit 3. Fig. 5 is a perspective view of the main frame 20 and the power input unit 3 as seen from the front side (X1 side). As shown in Fig. 4, the power input unit 3 includes a power input terminal block 4, and a first power input unit 5A and a second power input unit 5B to which AC current is supplied via the power input terminal block 4.

[0031] As shown in Fig. 4, one of the two power feed cables 40 drawn into the housing 2 includes three power feed lines 40A for supplying three-phase AC current for the drive power supply and one earth wire GL1 connected to the ground terminal of the external AC power supply. The second power feed cable 40 includes two power feed lines 40B for supplying two-phase AC current for the control power supply and one earth wire GL2 connected to the ground terminal of the external AC power supply. The three power feed lines 40A and two power feed lines 40B are connected to the power supply input terminal block 4. As will be described later, the earth wires GL1 and GL2 are connected to the frame ground terminal block 10 (see Fig. 5) rather than to the power supply input terminal block 4.

[0032] The 200V AC current input to the power supply input unit 3 is supplied to the first power supply input unit 5A and the second power supply input unit 5B via the power supply input terminal block 4. Three-phase AC current, which serves as the drive power supply, is input to the first power supply input unit 5A via the power supply line 40A and the power supply input terminal block 4. Three-phase AC current, which serves as the control power supply, is input to the second power supply input unit 5B via the power supply line 40B and the power supply input terminal block 4. A two-phase AC current is input.

[0033] 4, the first power supply input section 5A includes a first circuit breaker 51, a first surge protector 52, a first noise filter 53, and a second noise filter 54. The first noise filter 53 and the second noise filter 54 include filter circuits for removing noise superimposed on the AC current supplied to the first power supply input section 5A. The first circuit breaker 51 is a no-fuse breaker. The first circuit breaker 51 and the first surge protector 52 are disposed in a current supply path connecting the power supply input terminal block 4 and the first noise filter 53.

[0034] The second power supply input unit 5B includes a second circuit breaker 55, a second surge protector 56, a third noise filter 57, and a distribution connector 58. The third noise filter 57 includes a filter circuit for removing noise superimposed on the AC current supplied to the second power supply input unit 5B. The second circuit breaker 55 is a circuit protector. The second circuit breaker 55 and the second surge protector 56 are disposed in the current supply path connecting the power supply input terminal block 4 and the third noise filter 57.

[0035] The distribution connector 58 distributes the AC current output from the second noise filter 54 to multiple supply destinations. The AC current distributed from the distribution connector 58 is converted into a control current with a voltage different from that of the drive current. For example, the AC current distributed from the distribution connector 58 generates a 24V DC current supplied to the fan 6 and a 5V DC current supplied to the control circuit board.

[0036] The power input unit 3 is a unit that is elongated in the X direction as a whole. As shown in FIGS. 2 and 4, the power input terminal block 4 is disposed at the front end (X1 end) of the power input unit 3. The first and second circuit breakers 51 and 55 are disposed side by side above the power input terminal block 4 (Z2 side) at the front end (X1 end) of the power input unit 3. As shown in FIG. 3, the first surge protector 52 is disposed behind the first circuit breaker 51 (X2 side). As shown in FIG. 2, the second surge protector 56 is disposed behind the second circuit breaker 55 (X2 side). The front ends of the first and second circuit breakers 51 and 55 protrude forward (in the X1 direction) beyond the power input terminal block 4 and are disposed in the opening 31 of the interface panel 21A (see FIG. 1). The power input terminal block 4 is disposed inside the interface panel 21A.

[0037] 3, the first noise filter 53 and the second noise filter 54 are arranged in the front-to-rear direction (X direction) behind the Y1-side portion (X2 side) of the power input terminal block 4. The first noise filter 53 is arranged behind (X2 side) the power input terminal block 4, and the second noise filter 54 is arranged behind (X2 side) the first noise filter 53.

[0038] As shown in Fig. 2, the third noise filter 57 and the distribution connector 58 are arranged in the front-to-rear direction (X direction) behind the Y2-side portion (X2 side) of the power input terminal block 4. The third noise filter 57 is arranged behind (X2 side) the power input terminal block 4, and the distribution connector 58 is arranged behind (X2 side) the third noise filter 57. As shown by the dashed line in Fig. 3, the third noise filter 57 is arranged in a position aligned with the first noise filter 53 in the Y direction. The distribution connector 58 is arranged in a position aligned with the rear end of the second noise filter 54 in the Y direction.

[0039] The power input unit 3 is unitized by fixing the power input terminal block 4, the electronic elements constituting the first power input unit 5A, and the electronic elements constituting the second power input unit 5B to a metal base plate 60 with screws. The main frame 20 has a power input unit installation surface 32 on which the power input unit 3 is installed. The power input unit 3 is mounted by attaching the base plate 60 to the power input unit installation surface 32. The power input unit is fixed to the main frame 20 by screwing it to the surface 32. Therefore, as shown in FIGS.

[0040] The base plate 60 includes a first plate portion 61 parallel to the bottom plate 26 and a second plate portion 62 bent in the Z2 direction from the X1-side end of the first plate portion 61. As shown in FIGS. 2 and 3 , the power input terminal block 4, the first circuit breaker 51, the first surge protector 52, the second circuit breaker 55, and the second surge protector 56 are fixed to the second plate portion 62. The power input terminal block 4, the first circuit breaker 51, and the second circuit breaker 55 are disposed on the X1 side of the second plate portion 62, and the first surge protector 52 and the second surge protector 56 are disposed on the X2 side of the second plate portion 62. The first noise filter 53, the second noise filter 54, the third noise filter 57, and the distribution connector 58 are fixed to the first plate portion 61.

[0041] (Frame ground terminal block) In this embodiment, the protective earth wire PE1 of the power input terminal block 4, the protective earth wire PE2 of the first noise filter 53, the protective earth wire PE3 of the second noise filter 54, the protective earth wire PE4 of the third noise filter 57, the protective earth wire PE5 of the distribution connector 58, the protective earth wire PE6 of the first surge protector 52, and the protective earth wire PE7 of the second surge protector 56 are drawn out from the power input section 3 in the X1 direction.

[0042] The housing 2 is equipped with a frame ground terminal block 10 to which five of the seven protective earth wires (protective earth wires PE1 to PE5) of the power input unit 3 and the earth wires GL1 and GL2 of the power supply cable 40 are connected. As shown in Figures 2, 3, and 5, the frame ground terminal block 10 is disposed on the outer edge of the X1 side of the bottom plate 26. Therefore, when the interface panel 21A is removed from the main frame 20, the frame ground terminal block 10 is disposed in a position that is easily accessible from the opening in the front frame 27A.

[0043] The frame ground terminal block 10 is disposed on the front side (X1 side) of the power input unit 3, and is disposed adjacent to the power input unit 3 in the front-to-rear direction (X direction) on the power input unit installation surface 32. Therefore, the power input terminal block 4 and the frame ground terminal block 10, which are disposed at the end of the X1 side of the power input unit 3, are disposed adjacent to each other in the front-to-rear direction (X direction).

[0044] The frame ground terminal block 10 is made of the same metal material as the mainframe 20. In this embodiment, the frame ground terminal block 10 and the mainframe 20 are made of SPCC (cold-rolled steel plate). The frame ground terminal block 10 is fixed to the mainframe 20 by welding. The frame ground terminal block 10 and the mainframe 20 are welded together before plating, and then plated after welding. Therefore, the frame ground terminal block 10 and the mainframe 20 are welded together with their unplated base surfaces in contact with each other.

[0045] FIG. 6 is a perspective view of a portion of the mainframe 20 to which the frame ground terminal block 10 is fixed. FIG. 7 is a perspective view of the frame ground terminal block 10 as viewed obliquely from above and below. As shown in FIGS. 3, 6, and 7, the frame ground terminal block 10 includes a fixed plate 11 that abuts against the bottom plate 26, an inclined plate 13 with multiple screw holes 12, and a connecting plate 14 that connects the fixed plate 11 and the inclined plate 13. The fixed plate 11 extends in the Y direction. The fixed plate 11 abuts against the bottom plate 26 without being plated and is welded to the bottom plate 26. The connecting plate 14 includes a side plate 15 that bends at a substantially right angle from the X1-side end of the fixed plate 11 and rises in the Z2 direction, and an upper plate 16 that bends at a substantially right angle from the X1-side end of the side plate 15 and extends in the X1 direction. The inclined plate 13 extends from the X1-side end of the upper plate 16 toward the outer edge of the bottom plate 26.

[0046] The inclined plate 13 extends in the Y direction along the outer edge of the bottom plate 26 on the X1 side. The inclined plate 13 constitutes an earth wire fixing surface provided with a plurality of screw holes 12 to fix the protective earth wires PE1 to PE5 and the earth wires GL1 and GL2. The inclined plate 13 is inclined at an angle of 45 degrees or close to 45 degrees with respect to the bottom plate 26. More specifically, the inclined plate 13 is inclined in a direction away from the bottom plate 26 (toward the Z2 side) as it extends from the outer edge of the bottom plate 26 toward the inside of the bottom plate 26 (toward the X2 side). In other words, when viewed from diagonally above with the interface panel 21A removed, the inclined plate 13 is angled so that the screw holes 12 are visible from the front, and is inclined in a direction that makes it easy to screw the protective earth wires PE1 to PE5 and the earth wires GL1 and GL2.

[0047] Seven screw holes 12 are provided in the frame ground terminal block 10. Five of the seven protective earth wires (protective earth wires PE1 to PE5) and the earth wires GL1 and GL2 of the power supply cable 40 are fixed one by one to the seven screw holes 12 arranged in a row on the inclined plate 13 using screws (not shown) made of conductive metal. In addition, the protective earth wire PE6 of the first surge protector 52 and the protective earth wire PE7 of the second surge protector 56 are connected to the power input terminal block 4, and are connected to the frame ground terminal block 10 via the power input terminal block 4 and the protective earth wire PE1.

[0048] As described above, the power input terminal block 4 is disposed adjacent to the frame ground terminal block 10, so the route for routing the protective earth wire PE1 of the power input terminal block 4 is short. In addition, the first surge protector 52 and the second surge protector 56 are fixed to the second plate portion 62 of the base plate 60 on the Z2 side of the power input terminal block 4, so the route for routing the frame ground wires FG6, FG7 of the first surge protector 52 and the second surge protector 56 is short.

[0049] 3, the first noise filter 53, the second noise filter 54, the third noise filter 57, and the distribution connector 58 are arranged on the opposite side (X2 side) of the frame ground terminal block 10 with respect to the power input terminal block 4. Therefore, the frame ground wires PE2 to PE5 can be drawn forward from the rear of the power input terminal block 4, passing along the side (Y2 side) of the power input terminal block 4, so the route for drawing the protective earth wires PE6 and PE7 is simple and relatively short.

[0050] (Conductor noise voltage test) Fig. 8 shows noise waveforms in a noise terminal voltage test for the controller of this embodiment and a conventional controller. Fig. 8(a) shows the noise waveform in a noise terminal voltage test for the conventional controller, and Fig. 8(b) shows the noise waveform in a noise terminal voltage test for the controller of this embodiment. Unlike this embodiment, the conventional controller has a structure in which a plated frame ground terminal block is screwed to a plated housing part.

[0051] The noise terminal voltage test is performed in a shielded room by placing a line impedance stabilization network between the controller 1 and the AC power supply, and measuring the noise output to the measurement terminals of the line impedance stabilization network with a spectrum analyzer. In the noise waveform diagrams of Figures 8(a) and 8(b), the horizontal axis represents frequency and the vertical axis represents noise level. The limit values ​​(QP) and limit values ​​(AV) shown in Figures 8(a) and 8(b) are values ​​that comply with the common EMC standard (EN61000-6-4 Class A).

[0052] From the noise waveform diagram of FIG. 8(a), it can be seen that the conventional controller has a margin of only 0.2 dB relative to the limit value at frequencies F1 and F2, and therefore is unable to completely reduce noise. In contrast, the controller 1 of this embodiment, as can be seen from the noise waveform diagram of FIG. 8(b), The margin for the limit values ​​at numbers F1 and F2 is 5 dB or more, which is an allowable level. Therefore, by adopting the configuration of the frame ground terminal block 10 of this embodiment, noise resistance performance is improved compared to the conventional example.

[0053] (Main effect of this form) As described above, the controller 1 of this embodiment includes a metal housing 2, a power supply input unit 3 to which AC current is input from an external power supply, a DC / AC conversion circuit that converts the AC current supplied from the power supply input unit 3 to DC current, and a drive current generation unit that generates a drive current to be output to the outside based on the DC current supplied from the DC / AC conversion circuit. The power supply input unit 3 includes a power supply input terminal block 4 disposed within the housing 2 and noise filters (first noise filter 53, second noise filter 54, third noise filter 57) to which AC current is input via the power supply input terminal block 4. The housing 2 includes a main frame 20 on which the power supply input unit 3 is installed and a frame ground terminal block 10 to which the protective earth wires PE1 to PE5 of the power supply input unit 3 are connected. The frame ground terminal block 10 and the main frame 20 are made of the same metal and are welded together with their base surfaces, which are not coated with a plating film, in contact with each other.

[0054] In this embodiment, the frame ground terminal block 10 is directly fixed to the mainframe 20, which is a high-capacity metal component constituting the housing 2 of the controller 1. This reduces ground resistance compared to when other components are interposed between the mainframe 20 and the frame ground terminal block 10. Furthermore, because the base surfaces (not including the plated coating) are abutted and welded together, contact resistance between the mainframe 20 and the frame ground terminal block 10 is low. This reduces noise emissions and enhances noise resistance. Furthermore, since the frame ground terminal block 10 is fixed by welding, reliable contact is achieved, eliminating contact resistance variations due to screw tightening torque variations and suppressing variations in noise resistance. This allows for a simplified noise filter while still achieving the required noise resistance, thereby reducing noise filter costs. Furthermore, eliminating screw fastening holes from the frame ground terminal block 10 allows for a smaller frame ground terminal block 10, reducing component costs, and eliminating the risk of mis-disassembly.

[0055] In this embodiment, the frame ground terminal block 10 is disposed on the power input unit installation surface 32 of the main frame 20. By disposing the power input unit 3 and the frame ground terminal block 10 on the same surface in this way, the frame ground terminal block 10 can be disposed near the power input unit 3, which improves the workability when routing and connecting the protective earth wires PE1 to PE5 of the power supply unit to the frame ground terminal block 10.

[0056] In this embodiment, the main frame 20 includes the bottom plate 26 of the housing 2 and a frame-shaped housing frame 27 connected to the outer edge of the bottom plate 26, and therefore has the largest capacity among the metal members constituting the housing 2. In addition, a power input unit installation surface 32 is provided on the bottom plate 26, and the frame ground terminal block 10 is disposed on the outer edge of the bottom plate 26. In this configuration, the frame ground terminal block 10 can be easily accessed by removing an outer panel (e.g., interface panel 21A) fixed to the housing frame 27. This improves the workability when connecting the protective earth wires PE1 to PE5 to the frame ground terminal block 10.

[0057] In this embodiment, the frame ground terminal block 10 includes a fixed plate 11 that abuts against the bottom plate 26, and an inclined plate 13 that extends along the outer edge of the bottom plate 26. The inclined plate 13 forms a frame ground wire fixing surface. The inclined plate 13 inclines in a direction away from the bottom plate 26 as it approaches the power input unit 3 from the outer edge. Therefore, when the frame ground terminal block 10 placed on the bottom plate 26 is viewed from diagonally above, the screw holes 12 in the inclined plate 13 are visible from the front, which improves the workability when connecting the protective earth wires PE1 to PE5.

[0058] In this embodiment, the power input terminal block 4 is arranged at the tip of the power input unit 3 on the frame ground terminal block 10 side (i.e., the X1 side), so the power input terminal block 4 and the frame ground terminal block 10 are close to each other. This makes it easy to connect the frame ground wire FG1 of the power input terminal block 4 to the frame ground terminal block 10. Furthermore, because the power input terminal block 4 and the frame ground terminal block 10 are arranged together on the tip side (X1 side) of the power input unit 3, wiring work can be done efficiently.

[0059] In this embodiment, the power feed cable 40 drawn into the housing 2 includes power feed lines 40A and 40B that supply AC current from an AC power supply and ground wires GL1 and GL2 that are connected to the ground terminals of the AC power supply, with the power feed lines 40A and 40B connected to the power supply input terminal block 4 and the ground wires GL1 and GL2 connected to the frame ground terminal block 10. In this way, by directly connecting the ground wires GL1 and GL2 of the AC power supply to the frame ground terminal block 10, the frame ground can be effectively earthed. Therefore, by concentrating the protective earth wires PE1 to PE5 of the power input unit 3 at the frame ground terminal block 10, the power input unit 3 can be effectively earthed via the frame ground terminal block 10.

[0060] In this embodiment, the power input unit 3 includes circuit breakers (first circuit breaker 51, second circuit breaker 55) and surge protectors (first surge protector 52, second surge protector 56) that are arranged in a current supply path connecting the power input terminal block 4 and noise filters (first noise filter 53, third noise filter 57). A protective earth wire PE1 of the power input terminal block 4 and protective earth wires PE2, PE3, and PE4 of the noise filters (first noise filter 53, second noise filter 54, third noise filter 57) are connected to the frame ground terminal block 10. Meanwhile, a protective earth wire PE6 of the first surge protector 52 and a protective earth wire PE7 of the second surge protector 56 are connected to the power input terminal block 4 and are connected to the frame ground terminal block 10 via the power input terminal block 4 and the protective earth wire PE1.

[0061] In this way, in this embodiment, many of the protective earth wires of the power input unit 3 are concentrated at the frame ground terminal block 10. Therefore, by connecting the earth wires GL1 and GL2 of the AC power supply to the frame ground terminal block 10, many of the electronic elements that make up the power input unit 3 are earthed via the frame ground terminal block 10, resulting in high noise resistance. Therefore, the required noise resistance performance can be obtained even if the noise filter is simplified, and the cost of the noise filter can be reduced.

[0062] In this embodiment, the power supply input unit 3 is equipped with a distribution connector 58 that distributes the AC current that has passed through the third noise filter 57. The frame ground terminal block 10 is connected to the protective earth wire PE1 of the power supply input terminal block 4, the protective earth wire PE4 of the third noise filter 57, and the protective earth wire PE5 of the distribution connector 58. This reduces the noise in the AC current supplied from the distribution connector 58, further improving noise resistance.

[0063] In this embodiment, the power supply input unit 3 includes a first power supply input unit 5A that supplies an AC current for generating a drive current, and a second power supply input unit 5B that supplies an AC current for generating a control current with a voltage different from that of the drive current. The first power supply input unit 5A includes a first wiring circuit breaker 51, a first surge protector 52, a first noise filter 53, and a second noise filter 54. The second power supply input unit 5B includes a second wiring circuit breaker 55, a second surge protector 56, a third noise filter 57, and a distribution connector 58. The frame ground terminal block 10 is connected to a protective earth wire PE1 of the power supply input terminal block 4 and to protective earth wires P1 of the first noise filter 53 and the second noise filter 54 provided in the first power supply input unit 5A. E2 and PE3 are connected, as well as protective earth wire PE4 of third noise filter 57 provided in second power supply input section 5B and protective earth wire PE5 of distribution connector 58. Furthermore, protective earth wire PE6 of first surge protector 52 and protective earth wire PE7 of second surge protector 56 are connected to power supply input terminal block 4 as described above, and are connected to frame ground terminal block 10 via power supply input terminal block 4 and protective earth wire PE1. Therefore, the electronic elements constituting first power supply input section 5A and the electronic elements constituting second power supply input section 5B are each grounded via frame ground terminal block 10, thereby reducing noise in the control current and drive current.

[0064] The configuration of the electronic elements constituting the first power input section 5A and the second power input section 5B is not limited to the above-described configuration and can be modified as appropriate. For example, in the above-described configuration, the first power input section 5A is equipped with two noise filters and the second power input section 5B is equipped with one noise filter, but the number of noise filters is not limited to the above-described configuration. Also, the first surge protector 52 and the second surge protector 56 may be omitted.

[0065] (Variation) FIG. 9 is a perspective view showing the connection of protective earth wires PE1-PE7 when a modified frame terminal block 10A is used. The frame terminal block 10A shown in FIG. 9 has nine screw holes 12. Therefore, in addition to the protective earth wires PE1-PE5, the protective earth wire PE6 of the first surge protector 52 and the protective earth wire PE7 of the second surge protector 56 are directly connected to the frame terminal block 10A. Therefore, all of the protective earth wires of the electronic elements that make up the power input unit 3 are directly connected to the frame terminal block 10A, further improving noise resistance. Furthermore, as in the above embodiment, the earth wires GL1 and GL2 are directly connected to the frame terminal block 10A, so each electronic element that makes up the power input unit 3 can be effectively earthed. [Explanation of symbols]

[0066] 1...controller, 2...chassis, 2a...front, 2b...rear, 2c, 2d...side, 2e...bottom, 2f...top, 3...power input section, 4...power input terminal block, 5A...first power input section, 5B...second power input section, 6...fan, 10, 10A...frame ground terminal block, 11...fixing plate, 12...screw hole, 13...inclined plate, 14...connection plate, 15...side plate, 16...top plate, 20...main frame, 21A, 21B, 21C...interface panel, 22...rear panel, 23, 24...side plate, 25...top plate, 26...bottom plate, 27...chassis frame, 27A...front frame, 27B...side frame, 27C...top frame 1... Socket, 28... Sleeve, 29... External output connector, 30... External connection connector, 31... Opening, 32... Power input unit installation surface, 40... Power supply cable, 40A, 40B... Power supply line, 51... First wiring circuit breaker, 52... First surge protector, 53... First noise filter, 54... Second noise filter, 55... Second wiring circuit breaker, 56... Second surge protector, 57... Third noise filter, 58... Distribution connector, 60... Base plate, 61... First plate portion, 62... Second plate portion, GL1, GL2... Earth wire, PE1, PE2, PE3, PE4, PE5, PE6, PE7... Protective earth wire

Claims

1. A metal housing and a power supply input section to which AC current is input from an external power supply; a DC / AC conversion circuit that converts AC current supplied from the power supply input unit into DC current, and a drive current generation unit that generates a drive current to be output to an external device based on the DC current supplied from the DC / AC conversion circuit, the power supply input unit includes a power supply input terminal block disposed within the housing and at least one noise filter to which AC current is input via the power supply input terminal block; the housing includes a main frame on which the power input unit is installed and a frame ground terminal block to which a protective earth wire of the power input unit is connected, A controller characterized in that the frame ground terminal block and the main frame are made of the same metal and are welded together with their base surfaces, which are not coated with plating, in contact with each other.

2. the main frame includes a power input unit installation surface on which the power input unit is installed, 2. The controller according to claim 1, wherein the frame ground terminal block is disposed on a surface on which the power input unit is installed.

3. the main frame includes a bottom plate of the housing and a frame-shaped housing frame connected to an outer edge of the bottom plate, the power input unit installation surface is provided on the bottom plate, The controller according to claim 2 , wherein the frame ground terminal block is disposed on an outer edge of the bottom plate.

4. the frame ground terminal block includes a fixed plate that contacts the bottom plate and an inclined plate that extends along the outer edge of the bottom plate, and the protective earth wire is fixed to the inclined plate; The controller according to claim 3 , wherein the inclined plate is inclined in a direction away from the bottom plate as it approaches the power input portion from the outer edge.

5. 5. The controller according to claim 1, wherein the power input terminal block is disposed at a tip of the power input section on the side of the frame ground terminal block.

6. the power supply cable drawn into the housing includes a power supply line for supplying AC current from an AC power supply and a ground line connected to a ground terminal of the AC power supply; the power supply line is connected to the power input terminal block; 6. The controller according to claim 1, wherein the earth wire is connected to the frame ground terminal block.

7. the power supply input unit includes a molded-case circuit breaker disposed in a current supply path connecting the power supply input terminal block and the noise filter, 7. The controller according to claim 1, wherein a protective earth wire of the power supply input terminal block and a protective earth wire of the noise filter are connected to the frame ground terminal block.

8. the power supply input unit includes a surge protector disposed in a current supply path connecting the power supply input terminal block and the noise filter, 8. The controller according to claim 7, wherein the protective earth wire of the surge protector is connected directly to the frame ground terminal block or connected to the frame ground terminal block via the power input terminal block.

9. the power supply input unit includes a distribution connector that distributes the AC current that has passed through the noise filter; A controller as claimed in any one of claims 1 to 8, characterized in that the frame ground terminal block is connected to a protective earth wire of the power supply input terminal block, a protective earth wire of the noise filter, and a protective earth wire of the distribution connector.

10. the power supply input unit includes a first power supply input unit that supplies an AC current for generating a drive current, and a second power supply input unit that supplies an AC current for generating a control current having a voltage different from that of the drive current; the first power supply input unit includes a first molded case circuit breaker, a first surge protector, and at least one of the noise filters; the second power input section includes a second molded case circuit breaker, a second surge protector, at least one of the noise filter and a distribution connector; a protective earth wire of the power supply input terminal block, a protective earth wire of each noise filter provided in the first power supply input section, a protective earth wire of each noise filter provided in the second power supply input section, and a protective earth wire of the distribution connector are connected to the frame ground terminal block; A controller as described in any one of claims 1 to 6, characterized in that the protective earth wire of the first surge protector and the protective earth wire of the second surge protector are connected directly to the frame ground terminal block or connected to the frame ground terminal block via the power input terminal block.

Images