Press-fit terminal, terminal structure, and semiconductor module

Abstract

Provided is a press-fit terminal that is easily press-fitted into a through hole and reliably prevents escape from the through hole. A press-fit terminal (40) that is to be connected to a substrate (35) that has a through hole (35c) has a press-fitting part (44) that is press-fitted into the through hole and thereby held inside the through hole and an engagement part (45) that engages an outer surface (35b) of the substrate outside the through hole and restricts movement of the press-fit terminal in the direction (F2) of escape from the through hole.

Description

[Technical Field]

[0001] The present invention relates to a press-fit terminal, a terminal structure, and a semiconductor module. [Background technology]

[0002] A known method for electrically connecting electronic components such as semiconductor devices to a circuit board is to press-fit a press-fit terminal on the electronic component into a through-hole in the circuit board. The press-fit terminal has a press-fit portion whose width and thickness are larger than the diameter of the through-hole, and is inserted into the through-hole in a deformed state that narrows the press-fit portion. This causes the outer surface of the press-fit portion to press against the inner surface of the through-hole, holding the press-fit terminal in place.

[0003] In press-fit terminals, if the terminal width or thickness is increased to increase the retention force due to press-fitting in order to prevent the terminal from coming out of the through-hole, this increases the press-fit load (resistance during press-fitting), making the press-fit terminal more likely to break or bend during insertion. If the terminal width or thickness of the press-fit portion is reduced to avoid this problem and the retention force due to press-fitting is set low, the press-fit terminal may come out of the through-hole more easily, or the contact of the press-fit portion with the inner surface of the through-hole may become unstable, resulting in poor electrical continuity. Therefore, it has been difficult to determine the optimal dimensions of a press-fit terminal that achieves both stable retention force and ease of press-fitting.

[0004] As one solution to this problem, Patent Document 1 describes a press-fit terminal in which sawtooth grooves are provided on the outer edge of the press-fit portion to increase the holding force when press-fitted into a through-hole.

[0005] Patent document 2 describes a configuration in which multiple leads protruding from an electronic component are inserted into lead connection holes in a motherboard to make an electrical connection, in which a hook-shaped protrusion is provided on a spacer that holds the electronic component, the hook-shaped protrusion is inserted into a hole in the motherboard (a hole different from the lead connection hole), and a claw portion provided at the tip of the hook-shaped protrusion is engaged with the back side of the motherboard. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-222690 [Patent Document 2] Japanese Patent Application Publication No. 9-8182 [Patent Document 3] U.S. Patent No. 1,111,4780 [Patent Document 4] U.S. Patent No. 9,041,196 Summary of the Invention [Problem to be solved by the invention]

[0007] The press-fit terminal of Patent Document 1 obtains its holding force by press-fitting only through contact between the outer edge of the press-fit portion and the inner surface of the through-hole, and even if sawtooth grooves are provided on the outer edge of the press-fit portion, there is a limit to how much the holding force can be improved, making it difficult to reliably prevent the terminal from coming loose.

[0008] The hook-shaped protrusions in Patent Document 2 prevent the electronic component or spacer from coming loose by engaging the claws, but do not stabilize the electronic component or spacer in any other direction. Furthermore, since the hook-shaped protrusions for preventing the electronic component or spacer from coming loose are provided separately from the leads for electrical connection, problems arise such as an increase in the number of parts, a complicated structure, and higher manufacturing costs.

[0009] The present invention has been made in view of the above points, and one of its objects is to provide a press-fit terminal that can be easily press-fitted into a through-hole and can be reliably prevented from coming out of the through-hole. [Means for solving the problem]

[0010] A press-fit terminal according to one embodiment of the present invention is a press-fit terminal that is connected to a substrate having a through-hole, and has a press-fit portion that is held inside the through-hole by press-fitting, and a fitting portion that fits onto the outer surface of the substrate outside the through-hole and restricts movement of the press-fit terminal in the direction of removal from the through-hole. [Effects of the Invention]

[0011] According to the present invention, a press-fit terminal can be obtained that can be easily press-fitted into a through-hole and can be reliably prevented from coming out of the through-hole. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a plan view of a semiconductor device according to an embodiment of the present invention; [Figure 2] FIG. 2 is a cross-sectional view taken along line AA in FIG. [Figure 3] 1 is a schematic diagram illustrating an example of a circuit configuration of a semiconductor device according to an embodiment of the present invention; [Figure 4] 1 is a diagram showing a state in which a press-fit terminal according to a first embodiment is connected to a substrate. [Figure 5] FIG. 5 is a cross-sectional view taken along line BB in FIG. [Figure 6] 1A and 1B are front and side views of a press-fit terminal according to a first embodiment. [Figure 7] 1 is a diagram showing a state in which a press-fit terminal according to a first embodiment is being inserted into a through-hole in a substrate. [Figure 8] FIG. 10 is a front view of a press-fit terminal according to a second embodiment. [Figure 9] 10A and 10B are front and side views of a press-fit terminal according to a third embodiment. [Figure 10] 10 is a diagram showing a state in which a press-fit terminal according to a third embodiment is connected to a substrate. FIG. [Figure 11]FIG. 10 is a front view of a press-fit terminal according to a fourth embodiment. [Figure 12] 10A and 10B are front and side views of a press-fit terminal according to a fifth embodiment. [Figure 13] 10A and 10B are front and side views of a press-fit terminal according to a sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] A semiconductor device to which the press-fit terminal and terminal structure of the present invention can be applied will be described below. Fig. 1 is a plan view of the semiconductor device according to this embodiment. Fig. 2 is a cross-sectional view taken along line AA in Fig. 1. Fig. 3 is a schematic diagram showing an example of the circuit configuration of the semiconductor device according to this embodiment. Note that the semiconductor device shown below is merely an example, and is not limited to this and can be modified as appropriate.

[0014] In the following figures, the longitudinal direction of the semiconductor device is defined as the X direction, the lateral direction of the semiconductor device as the Y direction, and the height direction (thickness direction of the substrate) as the Z direction. The longitudinal direction of the semiconductor device indicates the direction in which multiple semiconductor modules (unit modules) are arranged. The X, Y, and Z axes shown in the figures are perpendicular to each other. In some cases, the X direction may be referred to as the left-right direction, the Y direction as the front-back direction, and the Z direction as the up-down direction. These directions (front-back, left-right, and up-down directions) are terms used for convenience of explanation, and their correspondence with the X, Y, and Z directions may change depending on the mounting orientation of the semiconductor device. In addition, in this specification, a plan view refers to the top or bottom of the semiconductor device as viewed from the Z direction.

[0015] A semiconductor device 1 according to this embodiment is applied to a power conversion device such as a power control unit, and is a power semiconductor module that constitutes an inverter circuit. As shown in Figures 1 and 2, the semiconductor device 1 is configured to include a plurality of unit modules 2 (three in this embodiment), a cooler 3 that cools these unit modules 2, a case member 4 that houses the plurality of unit modules 2, and a sealing resin 5 that is poured into the case member 4. Note that in Figure 1, the sealing resin 5 is not shown in order to show the internal structure of the semiconductor device 1.

[0016] The unit module 2 includes an insulating substrate 6 and a semiconductor element 7 disposed on the insulating substrate 6. In this embodiment, three unit modules 2 are arranged side by side in the X direction. The three unit modules 2 constitute, for example, U phase, V phase, and W phase from the positive side in the X direction, and together form a three-phase inverter circuit. The unit modules 2 may also be called power cells or semiconductor units.

[0017] The cooler 3 includes a base plate 8 formed in a rectangular shape when viewed from above. The base plate 8 has a rectangular shape when viewed from above and is formed of a plate-like body of a predetermined thickness. The longitudinal direction of the base plate 8 extends in the left-right direction (X direction) of the semiconductor device 1, and the lateral direction of the base plate 8 extends in the front-rear direction (Y direction) of the semiconductor device 1. The base plate 8 has one surface (bottom surface) and the other surface (top surface). One surface forms the heat dissipation surface of the unit module 2. The other surface forms the bonding surface of the unit module 2.

[0018] The base plate 8 is made of a material with high heat dissipation properties (for example, an alloy of aluminum or copper). A plated layer of a predetermined thickness is formed on the surface of the base plate 8. The plated layer is preferably made of metal plating such as nickel. An insulating substrate 6 is placed on the upper surface of the base plate 8 via a bonding material S such as solder. A plurality of fins may be provided on the lower surface of the base plate 8 to improve heat dissipation.

[0019] The insulating substrate 6 is formed of, for example, a DCB (Direct Copper Bonding) substrate, an AMB (Active Metal Brazing) substrate, or a metal-based substrate. Specifically, the insulating substrate 6 has an insulating plate 20, a heat sink 21 disposed on the lower surface of the insulating plate 20, and a plurality of circuit boards 22 disposed on the upper surface of the insulating plate 20. The insulating substrate 6 is formed, for example, in a rectangular shape when viewed from above.

[0020] The insulating plate 20 is formed of an insulating material such as a ceramic material such as alumina (Al2O3), aluminum nitride (AlN), or silicon nitride (Si3N4), a resin material such as epoxy, or an epoxy resin material using a ceramic material as a filler. The insulating plate 20 may also be called an insulating layer or an insulating film.

[0021] The heat sink 21 has a predetermined thickness in the Z direction and is formed so as to cover the lower surface of the insulating plate 20. The heat sink 21 is formed from a metal plate having good thermal conductivity, such as copper or aluminum.

[0022] A plurality of circuit boards 22 are formed on the upper surface of the insulating plate 20. These circuit boards 22 are metal layers such as copper foil, and are formed in the shape of islands on the insulating plate while being electrically insulated from one another. The circuit boards 22 may also be called substrates or circuit layers.

[0023] A semiconductor element 7 is disposed on the upper surface of the insulating substrate 6 (circuit board 22) via a bonding material S such as solder. For convenience, two semiconductor elements 7 are shown per insulating substrate 6 in FIG. 1, but more semiconductor elements 7 may be disposed on the insulating substrate 6. The semiconductor element 7 is formed into a square or rectangular shape in plan view using a semiconductor substrate such as silicon (Si), silicon carbide (SiC), gallium nitride (GaN), or diamond.

[0024] The semiconductor element 7 may be a switching element such as an IGBT (Insulated Gate Bipolar Transistor) or a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor), or a diode such as an FWD (Free Wheeling Diode). The switching element and the diode may be connected in anti-parallel. Alternatively, the semiconductor element 7 may be an RC (Reverse Conducting)-IGBT element in which an IGBT and an FWD are integrated, a power MOSFET element, or an RB (Reverse Blocking)-IGBT element having sufficient withstand voltage against reverse bias.

[0025] The shape, number, and location of the semiconductor elements 7 can be changed as appropriate. The semiconductor elements 7 in this embodiment are vertical switching elements in which functional elements such as transistors are formed on a semiconductor substrate, but are not limited to this and may be horizontal switching elements.

[0026] The upper surface electrodes of the semiconductor element 7 are conductively connected to a predetermined circuit board 22 via a metal wiring board 10. The metal wiring board 10 is formed by bending a metal material such as copper, copper alloy, aluminum alloy, or iron alloy by press working or the like. For example, one end of the semiconductor element 7 and the metal wiring board 10 are joined by a bonding material S such as solder. The other end of the predetermined circuit board 22 and the metal wiring board 10 are joined by a bonding material S such as solder. These metal wiring boards 10 may be called lead frames.

[0027] A case member 4 is disposed on the outer periphery of the upper surface of the base plate 8. The case member 4 is joined to the base plate 8, for example, via an adhesive. The case member 4 has a shape that follows the outline of the base plate 8. More specifically, the case member 4 is formed in the shape of a rectangular frame having an opening 4a in the center. The rectangular opening 4a accommodates the above-mentioned three unit modules 2. In other words, the three unit modules 2 are accommodated in a space defined by the frame-shaped case member 4.

[0028] Main terminals for external connection (P terminal 16, N terminal 17, M terminal 18) and control terminals for control (press-fit terminals 40) are provided on the case member 4. Of a pair of wall portions 24, 25 facing each other in the short side direction (Y direction) of the case member 4, recesses 26, 27 that are rectangular in plan view are formed in the wall portion 24 located on the negative side in the Y direction.

[0029] The fastening portion 16a of the P terminal 16 is arranged in the recess 26. One P terminal 16 is arranged for each unit module 2. The P terminal 16 is formed by integrally molding the fastening portion 16a and the plate-shaped portion 16b. The fastening portion 16a is provided on one end (base end) side of the plate-shaped portion 16b. The other end (tip end) of the plate-shaped portion 16b is joined to the circuit board 22 of the insulating substrate 6 via a joining material S such as solder.

[0030] Similarly, the fastening portion 17a of the N terminal 17 is arranged in the recess 27. One N terminal 17 is arranged for each unit module 2. The N terminal 17 is formed by integrally molding the fastening portion 17a and the plate-like portion 17b. The fastening portion 17a is provided on one end (base end) side of the plate-like portion 17b. The other end (tip end) of the plate-like portion 17b is joined to the circuit board 22 of the insulating substrate 6 via a joining material S such as solder.

[0031] Of the pair of wall portions 24, 25 opposing each other in the short-side direction (Y direction) of the case member 4, the wall portion 25 on the positive side in the Y direction is formed with a recess 28 that is rectangular in plan view. A fastening portion 18a of the M terminal 18 is arranged in the recess 28. One M terminal 18 is arranged for each unit module 2. The M terminal 18 is formed by integrally molding the fastening portion 18a and the plate-like portion 18b. The fastening portion 18a is provided on one end (base end) side of the plate-like portion 18b. The other end (tip end) of the plate-like portion 18b is joined to the circuit board 22 of the insulating substrate 6 via a joining material S such as solder.

[0032] As shown in Fig. 2, a fastening screw 31 is threadedly engaged with a nut 30 held by the fastening portion 17a, thereby fastening the outer conductor 32 to the fastening portion 17a. Although Fig. 2 shows the structure of the fastening portion 17a, the fastening portions 16a and 18a are also connected to the outer conductor by a similar structure.

[0033] The P terminal 16, the N terminal 17, and the M terminal 18 constitute a metal wiring plate through which the main current flows. The P terminal 16, the N terminal 17, and the M terminal 18 constitute main terminals that can be connected to an external conductor, and one end of the P terminal 16, the N terminal 17, and the M terminal 18 is joined to a predetermined circuit plate 22 of the insulating substrate 6 via a joining material S.

[0034] These terminals are formed from metal materials such as copper, copper alloy, aluminum alloy, iron alloy, etc. The shape, arrangement, number, etc. of these terminals are not limited to those described above and can be changed as appropriate.

[0035] The case member 4 is also provided with a plurality of press-fit terminals 40 that protrude in the Z direction from the upper surface 25a of the wall portion 25. In this embodiment, four press-fit terminals 40 are provided for each unit module 2, and a total of 12 press-fit terminals 40 are arranged side by side at predetermined intervals in the X and Y directions (see FIG. 1).

[0036] Each press-fit terminal 40 is connected to an internal wiring 19. The internal wiring 19 is integrally molded (insert molded) so as to be embedded in the case member 4. Each internal wiring 19 extends to the outer periphery of the opening 4a, and a wiring member T (bonding wire) is connected to the internal wiring 19. Each internal wiring 19 is connected to an upper surface electrode of the semiconductor element 7 via the wiring member T.

[0037] 2, the press-fit terminals 40 are connected to a substrate 35 provided outside the semiconductor device 1. The substrate 35 includes a control circuit 36. The connection structure between the press-fit terminals 40 and the substrate 35 will be described in detail later.

[0038] Furthermore, a plurality of through holes 29 are formed along the outer periphery of the case member 4. The through holes 29 are holes for inserting screws (not shown) for fixing the semiconductor device 1. The through holes 29 penetrate all the way to the base plate 8 of the cooler 3.

[0039] The resin for the case member 4 may be selected from PPS, as well as insulating resins such as polybutylene terephthalate (PBT), polybutyl acrylate (PBA), polyamide (PA), acrylonitrile butadiene styrene (ABS), liquid crystal polymer (LCP), polyether ether ketone (PEEK), polybutylene succinate (PBS), urethane, and silicone. The selected resin may also be a mixture of two or more resins. The resin may contain a filler (e.g., glass filler) to improve strength and / or functionality.

[0040] The internal space defined by the frame-shaped case member 4 is filled with sealing resin 5. The insulating substrate 6 and the semiconductor element 7 mounted thereon are sealed within the space by the sealing resin 5. The case member 4 defines a space that accommodates a plurality of unit modules 2 (insulating substrate 6, semiconductor element 7) and the sealing resin 5.

[0041] The sealing resin 5 is made of a thermosetting resin. The sealing resin 5 preferably contains at least one of epoxy, silicone, urethane, polyimide, polyamide, and polyamideimide. For example, an epoxy resin mixed with a filler is suitable for the sealing resin 5 in terms of insulation, heat resistance, and heat dissipation.

[0042] Fig. 3 shows an example of a circuit configuration illustrating an application example of the semiconductor device 1. In Fig. 3, the same components as those shown in Fig. 1 and Fig. 2 are denoted by the same reference numerals, and their description will be omitted. The semiconductor device 1 shown in Fig. 3 is applied as an inverter that converts DC power supplied from a power source PS into AC power to drive an electric motor EM.

[0043] 3 includes switches SW1 to SW6 as a plurality of semiconductor elements 7. The switches SW1 to SW6 are, for example, IGBTs (Insulated Gate Bipolar Transistors). The collector terminals of the switches SW1, SW3, and SW5 are connected to the positive terminal of the power supply PS via one terminal of a capacitor C, and the emitter terminals of the switches SW2, SW4, and SW6 are connected to the negative terminal of the power supply PS via the other terminal of the capacitor C. The connection point between the emitter terminal of the switch SW1 and the collector terminal of the switch SW2 is connected to the U-phase input terminal of the electric motor EM, the connection point between the emitter terminal of the switch SW3 and the collector terminal of the switch SW4 is connected to the V-phase input terminal of the electric motor EM, and the connection point between the emitter terminal of the switch SW5 and the collector terminal of the switch SW6 is connected to the W-phase input terminal of the electric motor EM. The gate terminal of switch SW1, the gate terminal of switch SW2, the gate terminal of switch SW3, the gate terminal of switch SW4, the gate terminal of switch SW5, and the gate terminal of switch SW6 are each connected to a control unit Cnt provided outside the semiconductor device 1. The control unit Cnt is included in a control circuit 36 ​​(FIG. 2) on the substrate 35.

[0044] Each of the switches SW1 to SW6 may have a diode connected in anti-parallel (where anti-parallel connection means that the anode of the diode is connected to the emitter of the switch and the cathode of the diode is connected to the collector of the switch).The switches SW1 to SW6 may also be configured with MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) or the like.

[0045] The capacitor C smoothes the voltage output from the power supply PS to the unit module 2.

[0046] The control unit Cnt turns on or off each of the switches SW1 to SW6. By turning on or off each of the switches SW1 to SW6, the DC voltage output from the power supply PS is converted into three AC voltages that are 120 degrees out of phase with each other, and when these AC voltages are applied to the U-phase input terminal, V-phase input terminal, and W-phase input terminal of the electric motor EM, the electric motor EM is driven.

[0047] The substrate 35 has a bottom surface 35a facing the semiconductor device 1 and a top surface 35b facing the opposite side to the bottom surface 35a, and has a plurality of through holes 35c penetrating from the bottom surface 35a to the top surface 35b. The semiconductor device 1 is conductively connected to the substrate 35 via the press-fit terminals 40 by inserting the press-fit terminals 40 into the through holes 35c.

[0048] The through-hole 35c is a generally circular hole in a plan view. A contact portion is formed on the inner surface (inner peripheral surface) of the through-hole 35c using a plating layer or the like. In the following description, the radial dimension of the through-hole 35c is referred to as the hole diameter Q (see FIG. 4).

[0049] The press-fit terminal 40 is made of a conductive metal material. Copper is a suitable base material for the press-fit terminal 40 because of its workability during manufacturing and its conductivity, and phosphor bronze is particularly suitable because of its excellent spring properties and high strength. The press-fit terminal 40 is manufactured by pressing such a metal material. Furthermore, to prevent corrosion of the press-fit terminal 40, the surface of the press-fit terminal 40 may be plated with nickel, tin, or the like.

[0050] The detailed configuration of the press-fit terminal 40 of the first embodiment will be described with reference to Figs. 4 to 7. Figs. 4 and 5 show the press-fit terminal 40 connected to the substrate 35. Fig. 6 shows the press-fit terminal 40 in its initial state before being connected to the substrate 35. Fig. 7 shows the press-fit terminal 40 being inserted into the through-hole 35c of the substrate 35. Arrow F1 in the drawings indicates the direction (insertion direction) in which the press-fit terminal 40 is inserted into the through-hole 35c when connecting the press-fit terminal 40 to the substrate 35. Arrow F2 indicates the direction (removal direction) in which the press-fit terminal 40 is removed from the through-hole 35c when the press-fit terminal 40 is connected to the substrate 35.

[0051] The press-fit terminal 40 has a base portion 41 connected to the wall portion 25 of the case member 4, a guide portion provided at the tip, and a connection portion 43 provided between the base portion 41 and the guide portion .

[0052] 4, the base 41 has a rod-like shape and protrudes a predetermined length in the Z direction from the upper surface 25a of the wall 25. The base 41 has a prismatic or cylindrical shape.

[0053] The guide portion 42 has a shape that gradually becomes thinner from the base end connected to the connection portion 43 toward the tip end. The width of the guide portion 42 is smaller than the diameter Q of the through-hole 35c. The guide portion 42 makes it easier to insert the connection portion 43 into the through-hole 35c when connecting the press-fit terminal 40 to the board 35. When the connection portion 43 is connected to the board 35, the guide portion 42 passes through the through-hole 35c and protrudes outside (upward) from the board 35 (see FIG. 4).

[0054] The connection portion 43 is press-fit into the through-hole 35c of the substrate 35 and is fitted onto the top surface 35b, which is the outer surface of the substrate 35, outside the substrate 35. In both the front view and side view shown in FIG. 6, the connection portion 43 has dimensions larger than the base portion 41. In the following description, the width of the connection portion 43 in the front view of the press-fit terminal 40 is referred to as the terminal width. Furthermore, the width of the connection portion 43 in the side view of the press-fit terminal 40 is referred to as the terminal thickness. Both the terminal width and the terminal thickness represent the size of the connection portion 43 in the radial direction of the through-hole 35c (the direction perpendicular to the Z direction).

[0055] The connecting portion 43 has a flat surface 43a on the front side, a curved surface 43b on the back side of the flat surface 43a, and a recessed portion 43c in the center of the flat surface 43a. The recessed portion 43c is recessed relative to the flat surface 43a. As shown in Fig. 5, when the connecting portion 43 is viewed in a cross section perpendicular to the Z direction, the curved surface 43b has a semicircular convex shape, and the recessed portion 43c has a semicircular concave shape.

[0056] The connecting portion 43 has a press-fit portion 44 and a fitting portion 45. The press-fit portion 44 is located on the base end side of the connecting portion 43 that connects to the base portion 41, and the fitting portion 45 is located on the tip end side of the connecting portion 43 that connects to the guide portion 42. Therefore, when inserting the press-fit terminal 40 into the through-hole 35c, the fitting portion 45 passes through the through-hole 35c first, and then the press-fit portion 44 enters the through-hole 35c.

[0057] 6, the press-fit portion 44 gradually increases in width and thickness from the base end connected to the base 41 toward the tip of the press-fit terminal 40, and reaches a maximum near the center of the length of the connection portion 43 in the Z direction. The maximum terminal width of the press-fit portion 44 is defined as maximum terminal width W1, and the maximum terminal thickness of the press-fit portion 44 is defined as maximum terminal thickness d1. The press-fit portion 44 gradually decreases in width and thickness from the points of maximum terminal width W1 and maximum terminal thickness d1 toward the tip of the press-fit terminal 40. In other words, the press-fit portion 44 has a shape similar to part of an ellipse with its major axis oriented in the Z direction when viewed from the front.

[0058] 6, the terminal width and thickness of the fitting portion 45 gradually increase from the tip end connected to the guide portion 42 toward the base end of the press-fit terminal 40, and are greatest at the fitting surface 45a that forms the boundary with the press-fit portion 44. The maximum terminal width of this fitting portion 45 is designated as maximum terminal width W2, and the maximum terminal thickness of the fitting portion 45 is designated as maximum terminal thickness d2. When viewed from the front, the fitting portion 45 has a shape similar to part of an ellipse with its major axis oriented in the Z direction.

[0059] The relationship between the maximum terminal width W2 of the fitting portion 45 and the maximum terminal width W1 of the press-fit portion 44 is W2>W1. Furthermore, the relationship between the maximum terminal thickness d2 of the fitting portion 45 and the maximum terminal thickness d1 of the press-fit portion 44 is d2>d1. In other words, the size (terminal width and terminal thickness) of the fitting portion 45 in the radial direction of the through-hole 35c is larger than the size (terminal width and terminal thickness) of the press-fit portion 44, and the fitting portion 45 has a stepped fitting surface 45a between it and the press-fit portion 44.

[0060] In the initial state (FIG. 6) before press-fit terminal 40 is inserted into through-hole 35c, both the maximum terminal width W1 of press-fit portion 44 and the maximum terminal width W2 of mating portion 45 are larger than the hole diameter Q of through-hole 35c (FIG. 4). As shown in FIG. 7, during the process of inserting press-fit terminal 40 into through-hole 35c in insertion direction F1, when the outer surface (curved surface 43b) of connecting portion 43 comes into contact with the inner surface of through-hole 35c, connecting portion 43 is pressed inward and elastically deforms to reduce the terminal width. The thinning (removal) of connecting portion 43 by recess 43c allows connecting portion 43 to smoothly elastically deform.

[0061] 7 shows a stage during insertion in which fitting portion 45 is passing through through hole 35c. At this stage, the outer surface of fitting portion 45 abuts against the inner surface of through hole 35c, causing deformation as it is pushed inward, and the terminal width of fitting portion 45 temporarily becomes equal to or smaller than diameter Q of through hole 35c.

[0062] 7, the mating portion 45 passes through the through-hole 35c and comes out of the board 35, and the press-fit portion 44 enters the inside of the through-hole 35c, as shown in Fig. 4. After passing through the through-hole 35c, the mating portion 45 is no longer pressed in by the inner surface of the through-hole 35c, and it recovers from its elastic deformation, widening the terminal width.

[0063] In the state shown in FIG. 4, the outer surface of the press-fit portion 44 contacts the inner surface of the through-hole 35c, causing deformation that pushes it inward, resulting in a smaller terminal width than in the initial state shown in FIG. 6. The outer surface of the deformed press-fit portion 44 is pressed against the inner surface of the through-hole 35c, generating a holding force. This causes the press-fit portion 44 to be press-fitted into the through-hole 35c. The portion of the press-fit portion 44 that has the maximum terminal width W1 in the initial state contacts the inner surface of the through-hole 35c, and the press-fit portion 44 is stably held relative to the board 35. Furthermore, the outer surface of the press-fit portion 44 contacts the contact portion on the inner surface of the through-hole 35c, establishing a conductive connection between the press-fit terminal 40 and the contact portion of the through-hole 35c.

[0064] In the state in which the press-fit terminal 40 and the board 35 are fully connected as shown in FIG. 4, the mating surface 45a of the mating portion 45 located on the outside of the board 35 faces the top surface 35b of the board 35. The mating surface 45a abuts against the top surface 35b, thereby restricting movement of the press-fit terminal 40 in the removal direction F2 relative to the board 35. In other words, after passing through the through hole 35c, the mating portion 45 is mated with the top surface 35b, which is the outer surface of the board 35, on the outside of the board 35. In a plan view taken along the Z direction, area C shown in FIG. 5 is the mating location between the mating surface 45a of the mating portion 45 and the top surface 35b of the board 35.

[0065] As described above, the connection portion 43 of the press-fit terminal 40 is connected to the board 35 by using both the press-fit portion 44, which is press-fit and held inside the through-hole 35c, and the fitting portion 45, which fits onto the outer surface (top surface 35b) of the board 35 outside the through-hole 35c and restricts movement of the press-fit terminal 40 in the direction of removal from the through-hole 35c. Pressing the press-fit portion 44 into the through-hole 35c increases the degree of adhesion to the through-hole 35c, thereby achieving reliable electrical contact between the contact portion on the board 35 and the press-fit terminal 40. Furthermore, fitting the fitting portion 45 reliably restricts positional change of the press-fit terminal 40 in the Z direction relative to the board 35, and in particular, movement of the press-fit terminal 40 in the removal direction F2 (removal of the press-fit terminal 40 from the through-hole 35c).

[0066] Unlike the press-fit terminal 40 of this embodiment, press-fit terminals that are connected simply by press-fitting into a through-hole have the following problems. If the terminal width or thickness is increased in order to increase the retention force of the press-fit, the resistance when press-fitting into the through-hole becomes excessive, making the press-fit terminal more likely to break or bend. Conversely, if the terminal width or thickness is reduced, the press-fit terminal may be more likely to come out after being press-fitted into the through-hole, or the contact between the contact portion of the through-hole and the press-fit terminal may become poor. As a result, it has been very difficult to adjust the terminal width and thickness of the press-fit terminal to obtain the optimal retention force.

[0067] In contrast, in the press-fit terminal 40 of this embodiment, the connection portion 43 includes a press-fit portion 44 and a fitting portion 45. The press-fit portion 44 is responsible for press-fitting into the through-hole 35c and electrically connecting with the board 35, while the fitting portion 45 is responsible for preventing the press-fit terminal 40 from coming out of the through-hole 35c. By assigning different roles to the press-fit portion 44 and the fitting portion 45, it is possible to set and adjust the shapes of the press-fit terminal 40 while focusing on each role, which can easily improve the connectivity between the press-fit terminal 40 and the board 35. For example, because the fitting portion 45 prevents the press-fit terminal 40 from coming out, there is no need to excessively increase the terminal width or thickness of the press-fit portion 44 in order to prevent the press-fit terminal 40 from coming out, and the press-fit load when inserting the press-fit portion 44 into the through-hole 35c can be reduced.

[0068] When connecting the press-fit terminal 40 to the board 35, the mating portion 45, which has a larger terminal width and thickness than the press-fit portion 44, passes through the through-hole 35c, but because the mating portion 45 accounts for a small proportion of the entire connecting portion 43, the increase in the press-fit load due to the mating portion 45 is limited. Therefore, the press-fit terminal 40, which includes the mating portion 45, can be easily inserted into the through-hole 35c.

[0069] 4, the wall 25 of the case member 4 is further provided with a support portion 46 near the press-fit terminal 40. The support portion 46 is a rod-shaped or columnar protrusion that protrudes in the Z direction from the upper surface 25a of the wall 25. When the press-fit terminal 40 is connected to the board 35, the tip of the support portion 46 faces the lower surface 35a of the board 35. The lower surface 35a of the board 35 is a second outer surface located on the opposite side of one outer surface (upper surface 35b) that faces the mating surface 45a of the mating portion 45.

[0070] The tip of the support portion 46 abuts against the lower surface 35a of the board 35, thereby limiting movement of the press-fit terminal 40 in the insertion direction F1 relative to the board 35. In other words, the provision of the support portion 46 determines the maximum insertion amount of the press-fit terminal 40 into the through-hole 35c. The amount of protrusion of the support portion 46 from the upper surface 25a of the wall portion 25 is set so that the mating surface 45a of the mating portion 45 faces the upper surface 35b of the board 35 with a predetermined clearance. As described above, the mating of the mating portion 45 with the board 35 limits movement of the press-fit terminal 40 in the removal direction F2 relative to the board 35. Therefore, according to the structure shown in FIG. 4, a stable insertion position of the press-fit terminal 40 can be easily set in both the insertion direction F1 and the removal direction F2.

[0071] Next, modified examples of the press-fit terminal will be described with reference to FIGS.

[0072] Fig. 8 shows a press-fit terminal 50 of the second embodiment. Fig. 8 shows the press-fit terminal 50 in an initial state before being connected to the board 35, with the board 35 and through-hole 35c shown imaginarily by a two-dot chain line. The base portion 51 and guide portion 52 of the press-fit terminal 50 have the same configuration and function as the base portion 41 and guide portion 42 of the press-fit terminal 40 of the first embodiment, and detailed description thereof will be omitted.

[0073] The connection portion 53 of the press-fit terminal 50 has a press-fit portion 54, a fitting portion 55, and a second fitting portion 56. The fitting portion 55 is located on the tip side of the connection portion 53 that connects to the guide portion 52. The second fitting portion 56 is located on the base end side of the connection portion 53 that connects to the base portion 51. The press-fit portion 54 is located in the area between the fitting portion 55 and the second fitting portion 56.

[0074] The connecting portion 53 has a recess 53a. Similar to the recess 43c in the press-fit terminal 40 of the first embodiment, the recess 53a is provided as a lightening hole to make the connecting portion 53 easier to deform.

[0075] The press-fit portion 54 and the fitting portion 55 have configurations corresponding to the press-fit portion 44 and the fitting portion 45 of the first embodiment of the press-fit terminal 40. The press-fit portion 54 has a maximum terminal width W11 that is larger than the hole diameter Q of the through-hole 35c in an initial state, and is press-fitted into the through-hole 35c in a deformed state in which the terminal width is equal to or smaller than the hole diameter Q.

[0076] In an initial state, the fitting portion 55 has a maximum terminal width W12 that is larger than the maximum terminal width W11 of the press-fit portion 54. Then, when the fitting portion 55 passes through the through-hole 35c and protrudes outside the board 35, the fitting surface 55a (the stepped shape of the boundary with the press-fit portion 54) is fitted to face the upper surface 35b of the board 35. This restricts movement of the press-fit terminal 50 in the removal direction F2 relative to the board 35.

[0077] The second fitting portion 56 has a terminal width (and terminal thickness) that gradually increases from the base end connected to the base portion 51 toward the tip of the press-fit terminal 50, and the terminal width (and terminal thickness) is greatest at the second fitting surface 56a, which is a stepped portion at the boundary with the press-fit portion 54. The maximum terminal width of this second fitting portion 56 is defined as a maximum terminal width W13. The maximum terminal width W13 is greater than the hole diameter Q of the through-hole 35c.

[0078] With the press-fit portion 54 press-fitted into the through-hole 35c, the second fitting portion 56 is located outside the board 35, and the second fitting surface 56a faces the bottom surface 35a of the board 35. The second fitting surface 56a abuts against the bottom surface 35a, thereby restricting movement of the press-fit terminal 50 in the insertion direction F1 relative to the board 35. In other words, the fit between the second fitting portion 56 and the board 35 determines the maximum insertion amount of the press-fit terminal 50 into the through-hole 35c.

[0079] Therefore, with the press-fit terminal 50 having the press-fit portion 54, the fitting portion 55, and the second fitting portion 56, it is possible to easily set a stable insertion position of the press-fit terminal 50 in both the insertion direction F1 and the removal direction F2. Note that, because the movement of the press-fit terminal 50 in the insertion direction F1 is limited by the second fitting portion 56, a structure not including the support portion 46 shown in FIG. 4 can be employed.

[0080] 9 and 10 show a third embodiment of the press-fit terminal 60. Fig. 9 shows the press-fit terminal 60 in an initial state before being connected to the substrate 35. Fig. 10 shows the press-fit terminal 60 connected to the substrate 35. The base 61 and guide portion 62 of the press-fit terminal 60 have the same configuration and function as the base 41 and guide portion 42 of the press-fit terminal 40 of the first embodiment, and detailed description thereof will be omitted.

[0081] The connection portion 63 of the press-fit terminal 60 has a press-fit portion 64 and a fitting portion 65. The press-fit portion 64 is located on the base end side of the connection portion 63 that connects to the base portion 61. The fitting portion 65 is located on the tip end side of the connection portion 63 that connects to the guide portion 62.

[0082] The press-fit portion 64 and the fitting portion 65 are separated by a groove 66. When viewed from the front, the connection portion 63 has a shape similar to an ellipse with its major axis oriented in the Z direction, and the groove 66 is formed by cutting out a part of the ellipse. The fitting portion 65 has a fitting surface 65a that forms the inner surface of the groove 66.

[0083] The connecting portion 63 has a recess 63a. Similar to the recess 43c in the press-fit terminal 40 of the first embodiment, the recess 63a is provided as a lightening hole to facilitate deformation of the connecting portion 63. The groove 66 is formed from the outer surface of the connecting portion 63 to a predetermined depth (a depth that does not reach the recess 63a).

[0084] In an initial state, press-fit portion 64 has a maximum terminal width W21 that is larger than diameter Q of through-hole 35c (see FIG. 9). When press-fit terminal 60 is connected to substrate 35, press-fit portion 64 is press-fit into through-hole 35c in a deformed state where the terminal width is equal to or smaller than diameter Q (see FIG. 10).

[0085] The support portion 67 shown in Fig. 10 has the same function as the support portion 46 shown in Fig. 4. The support portion 67 is provided to protrude from the upper surface 25a of the wall portion 25, and the tip of the support portion 67 abuts against the lower surface 35a of the board 35, thereby restricting the movement of the press-fit terminal 60 in the insertion direction F1 relative to the board 35.

[0086] In an initial state, the fitting portion 65 has a maximum terminal width W22 that is larger than the hole diameter Q of the through-hole 35c (see FIG. 9). When the press-fit terminal 60 is connected to the board 35, the fitting portion 65 fits into the board 35 with the fitting surface 65a facing the upper surface 35b of the board 35 (see FIG. 10). This limits movement of the press-fit terminal 60 in the removal direction F2 relative to the board 35.

[0087] In other words, the press-fit portion 64 and the fitting portion 65 in the press-fit terminal 60 have the same functions as the press-fit portion 44 and the fitting portion 45 in the press-fit terminal 40 of the first embodiment. In the press-fit terminal 40, a step is provided between the press-fit portion 44 and the fitting portion 45 in the initial state, so that a fitting surface 45a is pre-existing on the outer surface of the connecting portion 43. In contrast, in the press-fit terminal 60, a groove 66 is provided between the press-fit portion 64 and the fitting portion 65 in the initial state, so that the fitting surface 65a appears on the outer surface of the connecting portion 63 by utilizing the difference in the amount of deformation between the press-fit portion 64 and the fitting portion 65 when the press-fit portion 64 is press-fitted into the through-hole 35c.

[0088] The press-fit terminal 60 differs from the press-fit terminal 40 of the first embodiment in that the maximum terminal width W21 of the press-fit portion 64 in the initial state is larger than the maximum terminal width W22 of the fitting portion 65. When the press-fit portion 64 is press-fitted into the through-hole 35c, the terminal width of the press-fit portion 64 becomes smaller than the terminal width of the fitting portion 65.

[0089] Fig. 11 shows a press-fit terminal 70 of the fourth embodiment. Fig. 11 shows the press-fit terminal 70 in an initial state before being connected to the board 35, with the board 35 and through-hole 35c shown imaginarily by two-dot chain lines. The base portion 71 and guide portion 72 of the press-fit terminal 70 have the same configuration and function as the base portion 41 and guide portion 42 of the press-fit terminal 40 of the first embodiment, and detailed description thereof will be omitted.

[0090] The connection portion 73 of the press-fit terminal 70 has a press-fit portion 74, a fitting portion 75, and a second fitting portion 76. The fitting portion 75 is located on the tip side of the connection portion 73 that connects to the guide portion 72. The second fitting portion 76 is located on the base end side of the connection portion 73 that connects to the base portion 71. The press-fit portion 74 is located in the area between the fitting portion 75 and the second fitting portion 76.

[0091] The press-fit portion 74 and the mating portion 75 are separated by a groove 77. The press-fit portion 74 and the second mating portion 76 are separated by a groove 78. The connecting portion 73 has a recess 73a. Similar to the recess 43c in the press-fit terminal 40 of the first embodiment, the recess 73a is provided as a lightening portion to make it easier to deform the connecting portion 73. The grooves 77 and 78 are formed to a predetermined depth (a depth that does not reach the recess 73a) from the outer surface of the connecting portion 73.

[0092] The press-fit portion 74 and the fitting portion 75 have configurations corresponding to the press-fit portion 64 and the fitting portion 65 of the third embodiment of the press-fit terminal 60. The press-fit portion 74 has a maximum terminal width W31 that is larger than the hole diameter Q of the through-hole 35c in an initial state, and is press-fitted into the through-hole 35c in a deformed state where the terminal width is equal to or smaller than the hole diameter Q.

[0093] In an initial state, the fitting portion 75 has a maximum terminal width W32 that is larger than the hole diameter Q of the through-hole 35c of the press-fit portion 74. Then, when the fitting portion 75 passes through the through-hole 35c and protrudes outside the board 35, the fitting surface 75a (the inner surface of the groove 77) is fitted to face the upper surface 35b of the board 35. This limits movement of the press-fit terminal 70 in the removal direction F2 relative to the board 35.

[0094] The second fitting portion 76 has a terminal width (and terminal thickness) that gradually increases from the base end connected to the base portion 71 toward the tip of the press-fit terminal 70, and the terminal width (and terminal thickness) is greatest at the second fitting surface 76a that forms the inner surface of the groove 78. The maximum terminal width of this second fitting portion 76 is defined as a maximum terminal width W33. The maximum terminal width W33 is greater than the hole diameter Q of the through-hole 35c.

[0095] With the press-fit portion 74 press-fitted into the through-hole 35c, the second fitting portion 76 is positioned outside the board 35, and the second fitting surface 76a faces the bottom surface 35a of the board 35. The second fitting surface 76a abuts against the bottom surface 35a, thereby restricting movement of the press-fit terminal 70 in the insertion direction F1 relative to the board 35. In other words, the maximum insertion amount of the press-fit terminal 70 into the through-hole 35c is determined by the fit between the second fitting portion 76 and the board 35.

[0096] Therefore, with the press-fit terminal 70 having the press-fit portion 74, the fitting portion 75, and the second fitting portion 76, it is possible to easily set a stable insertion position of the press-fit terminal 70 in both the insertion direction F1 and the removal direction F2. Note that, because the movement of the press-fit terminal 70 in the insertion direction F1 is limited by the second fitting portion 76, a structure that does not include the support portion 46 shown in Fig. 4 or the support portion 67 shown in Fig. 10 can be employed.

[0097] In this way, the press-fit portion 74, the fitting portion 75, and the second fitting portion 76 in the press-fit terminal 70 have the same functions as the press-fit portion 54, the fitting portion 55, and the second fitting portion 56 in the second form of press-fit terminal 50 (FIG. 8). In the press-fit terminal 50, in the initial state, a step shape is provided between the press-fit portion 54 and the fitting portion 55, and between the press-fit portion 54 and the second fitting portion 56, so that a fitting surface 55a and a second fitting surface 56a are already present on the outer surface of the connecting portion 53. In contrast, in the press-fit terminal 70, in the initial state, a groove 77 is provided between the press-fit portion 74 and the mating portion 75, and a groove 78 is provided between the press-fit portion 74 and the second mating portion 76.This makes use of the difference in the amount of deformation of the press-fit portion 74, the mating portion 75, and the second mating portion 76 when the press-fit portion 74 is pressed into the through-hole 35c, so that the mating surface 75a and the second mating surface 76a appear on the outer surface of the connection portion 73.

[0098] In the second form of press-fit terminal 50 (Figure 8), in the initial state, the mating portion 55 and the second mating portion 56 each have a step between them and the press-fit portion 54, and in the fourth form of press-fit terminal 70 (Figure 11), in the initial state, the mating portion 75 and the second mating portion 76 each have grooves 77 and 78 between them and the press-fit portion 74, but it is also possible to configure one of the mating portion and the second mating portion using a step shape and the other of the mating portion and the second mating portion using a groove.

[0099] Fig. 12 shows a press-fit terminal 80 of the fifth embodiment. Fig. 12 shows the press-fit terminal 80 in an initial state before being connected to the substrate 35. The base portion 81 and guide portion 82 of the press-fit terminal 80 have the same configuration and function as the base portion 41 and guide portion 42 of the press-fit terminal 40 of the first embodiment, and detailed description thereof will be omitted.

[0100] The connection portion 83 of the press-fit terminal 80 has a press-fit portion 84 and a fitting portion 85. The press-fit portion 84 is located on the base end side of the connection portion 83 that connects to the base portion 81. The fitting portion 85 is located on the tip end side of the connection portion 83 that connects to the guide portion 82.

[0101] The shape of the connection portion 83 in a front view is generally the same as the shape of the connection portion 43 in the press-fit terminal 40 of the first embodiment (see FIG. 6), and a step exists between the press-fit portion 84 and the fitting portion 85. The maximum terminal width W41 of the press-fit portion 84 is larger than the hole diameter Q of the through-hole 35c. The fitting portion 85 has a fitting surface 85a as a step shape at the boundary with the press-fit portion 84, and the maximum terminal width W42 at the fitting surface 85a is larger than the maximum terminal width W41 of the press-fit portion 84.

[0102] The difference between the press-fit terminal 40 of the first embodiment and the press-fit terminal 40 is that the connection portion 83 of the press-fit terminal 80 has a flat plate shape with a constant terminal thickness in a side view. That is, the connection portion 83 has parallel flat surfaces 83a and 83b on both sides in the thickness direction of the terminal. Furthermore, in the center of the connection portion 83, instead of a bottomed recess, a through-hole 83c is formed that penetrates from the flat surface 83a to the flat surface 83b. Similar to the recess 43c in the press-fit terminal 40 of the first embodiment, the through-hole 83c is formed as a lightening hole to make the connection portion 83 easier to deform.

[0103] The press-fit portion 84 and the fitting portion 85 of the press-fit terminal 80 have the same functions as the press-fit portion 44 and the fitting portion 45 of the first embodiment of the press-fit terminal 40. When the press-fit terminal 80 is connected to the board 35, the press-fit portion 84 is press-fit into the through-hole 35c in a deformed state in which the terminal width is equal to or less than the hole diameter Q.

[0104] When the press-fit terminal 80 is inserted into the through-hole 35c, the fitting portion 85 elastically deforms to reduce the terminal width and passes through the through-hole 35c, and after passing through the through-hole 35c, it recovers from the elastic deformation and fits with the fitting surface 85a facing the upper surface 35b of the board 35. This limits movement of the press-fit terminal 80 in the removal direction F2 relative to the board 35.

[0105] Fig. 13 shows a press-fit terminal 90 of the sixth embodiment. Fig. 13 shows the press-fit terminal 90 in an initial state before being connected to the substrate 35. The base 91 of the press-fit terminal 90 has the same configuration and role as the base 41 of the press-fit terminal 40 of the first embodiment, and detailed description thereof will be omitted.

[0106] The connection portion 93 of the press-fit terminal 90 differs from the press-fit terminals of the above types in that, when viewed from the front, it has a bifurcated structure with separated tips (an Ω-shape when viewed from the front). When viewed from the side, the connection portion 93 has a flat plate shape with a constant terminal thickness. The connection portion 93 has a pair of arms 93a and 93b that are approximately symmetrically shaped and spaced apart in the terminal width direction. The pair of arms 93a and 93b are connected at the base 91.

[0107] In the connection portion 93, the base end portions of the pair of arm portions 93a and 93b form a press-fit portion 94, and the tip end portions form a fitting portion 95. The maximum terminal width W51 of the press-fit portion 94 is larger than the diameter Q of the through-hole 35c. The fitting portion 95 has a stepped fitting surface 95a at the boundary between the pair of arm portions 93a and 93b and the press-fit portion 94. The maximum terminal width W52 of the fitting portion 95 at the fitting surface 95a is larger than the maximum terminal width W51 of the press-fit portion 94. The width of the tip portion of the fitting portion 95 is smaller than the diameter Q of the through-hole 35c, so that the fitting portion 95 can be inserted into the through-hole 35c from its tip side.

[0108] The press-fit portion 94 and the fitting portion 95 of the press-fit terminal 90 have the same functions as the press-fit portion 44 and the fitting portion 45 of the press-fit terminal 40 of the first embodiment. When the press-fit terminal 90 is inserted into the through-hole 35c, the connecting portion 93 elastically deforms to reduce the distance between the pair of arm portions 93a and 93b. Then, with the press-fit terminal 90 connected to the board 35, the press-fit portion 94 is press-fit into the through-hole 35c in a deformed state in which the terminal width is equal to or less than the hole diameter Q.

[0109] When the press-fit terminal 90 is inserted into the through-hole 35c, the fitting portion 95 elastically deforms to reduce the terminal width to less than the maximum terminal width W52 and passes through the through-hole 35c, and after passing through the through-hole 35c, the fitting portion 95 recovers from the elastic deformation and fits with the fitting surface 95a facing the upper surface 35b of the board 35. This limits movement of the press-fit terminal 90 in the removal direction F2 relative to the board 35.

[0110] The press-fit terminal 90 has a structure in which the tip ends of the pair of arm portions 93a and 93b are not connected, and therefore the press-fit terminal 90 is easily deformed in the terminal width direction, and the press-fit load can be reduced.

[0111] Although not shown in Figures 12 and 13, for the press-fit terminal 80 of the fifth form and the press-fit terminal 90 of the sixth form, it is preferable to provide a support portion 46 (Figure 4) or a support portion 67 (Figure 10) on the wall portion 25 to determine an appropriate insertion amount in the insertion direction F1.

[0112] Although the above embodiment has been described as an example of application to a press-fit terminal protruding from the wall portion 25 of the case member 4, it is also possible to apply the present invention to a terminal structure in another portion of the semiconductor device 1.

[0113] Furthermore, the press-fit terminal and terminal structure of the present invention can be applied to electronic devices other than power semiconductor modules.

[0114] In the above embodiment, the entire connection portion of the press-fit terminal is configured to be elastically deformable, but this is not limiting. For example, an elastically deformable configuration may be selected for the fitting portion that needs to restore its shape after passing through the through-hole and fit, and a plastically deformable configuration may be selected for the press-fit portion that remains pressed into the through-hole.

[0115] Although the embodiments and modifications have been described, other embodiments may be obtained by combining the above embodiments and modifications in whole or in part.

[0116] Furthermore, the present invention is not limited to the above-described embodiments and modifications, and may be variously changed, substituted, or modified within the scope of the spirit of the technical idea. Furthermore, if the technical idea can be realized in a different way due to technological advances or other derived technologies, it may be implemented using that method. Therefore, the claims cover all embodiments that may fall within the scope of the technical idea.

[0117] The features of the above embodiment are summarized below. The press-fit terminal according to the above embodiment is a press-fit terminal that is connected to a substrate having a through-hole, and has a press-fit portion that is held inside the through-hole by press-fitting, and an engagement portion that engages with the outer surface of the substrate outside the through-hole and restricts movement of the press-fit terminal in the direction of coming out of the through-hole.

[0118] In addition, in the press-fit terminal according to the above embodiment, the size of the mating portion in the radial direction of the through hole is larger than the size of the press-in portion, and the mating portion has a stepped mating surface between it and the press-in portion, and the mating surface faces the outer surface of the substrate.

[0119] Furthermore, the press-fit terminal according to the above embodiment has a groove between the mating portion and the press-in portion, the mating portion has a mating surface on the inner surface of the groove, and the mating surface faces the outer surface of the board.

[0120] In addition, the press-fit terminal according to the above embodiment has a second fitting portion that fits onto a second outer surface of the substrate opposite the outer surface outside the through hole, limiting the movement of the press-fit terminal in the direction of insertion into the through hole.

[0121] In addition, in the press-fit terminal according to the above embodiment, the size of the second fitting portion in the radial direction of the through hole is larger than the size of the press-fit portion, and the second fitting portion has a stepped second fitting surface between itself and the press-fit portion, and the second fitting surface faces the second outer surface of the substrate.

[0122] Furthermore, the press-fit terminal according to the above embodiment has a groove between the second mating portion and the press-in portion, the mating portion has a second mating surface on the inner surface of the groove, and the second mating surface faces the second outer surface of the substrate.

[0123] In addition, the terminal structure according to the above embodiment has a support portion that is provided on an electronic component having the press-fit terminal and abuts against a second outer surface opposite the outer surface of the substrate, thereby limiting the movement of the press-fit terminal in the direction of insertion into the through hole.

[0124] The semiconductor module according to the above embodiment includes a plurality of semiconductor elements and the terminal structure. [Industrial Applicability]

[0125] As described above, the present invention has the effect of providing a press-fit terminal that can be easily press-fitted into a through-hole and can be reliably prevented from coming loose from the through-hole, and is particularly useful for industrial or electrical semiconductor devices, etc.

[0126] This application is based on Japanese Patent Application No. 2022-180715, filed November 11, 2022, the contents of which are incorporated herein in their entirety. [Explanation of symbols]

[0127] 1: Semiconductor device (semiconductor module) 2: Unit module 3:Cooler 4: Case material 5: Sealing resin 6: Insulating substrate 7: Semiconductor elements 8: Base plate 10: Metal wiring board 16 :P terminal 17 :N terminal 18 :M terminal 19: Internal wiring 20: Insulating plate 21: Heat sink 22: Circuit board 35: Substrate 35a: Bottom surface (second outer surface) 35b:Top surface (outer surface) 35c:Through hole 40: Press-fit terminal 41: Base 42: Guide section 43: Connection part 44: Press-fit part 45: Fitting part 45a: Mating surface 46: Support part 50: Press-fit terminal 51: Base 52: Guide section 53: Connection part 54: Press-fit part 55: Fitting part 55a: Mating surface 56: Second fitting part 56a: Second mating surface 60: Press-fit terminal 61: Base 62: Guide section 63: Connection part 64: Press-fit part 65: Fitting part 65a: Mating surface 66: Groove 67: Support part 70: Press-fit terminal 71: Base 72: Guide section 73: Connection 74: Press-fit part 75: Fitting part 75a: Mating surface 76: Second fitting part 76a: 2nd mating surface 77: Groove 78: Groove 80: Press-fit terminal 81: Base 82: Guide section 83: Connection 84: Press-fit part 85: Fitting part 85a: Mating surface 90: Press-fit terminal 91: Base 93: Connection 93a: Arm 93b: Arm 94: Press-fit part 95: Fitting part 95a: Mating surface F1: Insertion direction F2: Exit direction Q: Pore diameter

Claims

1. A press-fit terminal for connection to a substrate having a through hole, a press-fit portion that is press-fitted and held inside the through hole; a fitting portion that fits onto an outer surface of the board outside the through hole and restricts movement of the press-fit terminal in a direction to be removed from the through hole; and A groove is provided between the fitting portion and the press-fit portion, and the fitting portion has a fitting surface on the inner surface of the groove, and the fitting surface faces the outer surface of the substrate. Press-fit terminals.

2. 2. The press-fit terminal according to claim 1, wherein the size of the mating portion in the radial direction of the through hole is larger than the size of the press-fit portion, the mating portion has a stepped mating surface between it and the press-fit portion, and the mating surface faces the outer surface of the board.

3. 3. The press-fit terminal according to claim 1, further comprising a second engaging portion that engages with a second outer surface of the substrate opposite the outer surface outside the through hole, thereby limiting movement of the press-fit terminal in the direction of insertion into the through hole.

4. 4. The press-fit terminal of claim 3, wherein the size of the second mating portion in the radial direction of the through hole is larger than the size of the press-fit portion, the second mating portion has a stepped second mating surface between it and the press-fit portion, and the second mating surface faces the second outer surface of the board.

5. 4. The press-fit terminal according to claim 3, further comprising a second groove between the second mating portion and the press-fit portion, the second mating portion having a second mating surface on the inner surface of the second groove, the second mating surface facing the second outer surface of the board.

6. A terminal structure having the press-fit terminal according to claim 1 or 2, A terminal structure having a support portion provided on an electronic component having the press-fit terminal, which abuts against a second outer surface opposite the outer surface of the substrate and limits movement of the press-fit terminal in the direction of insertion into the through hole.

7. A semiconductor module comprising a plurality of semiconductor elements and the terminal structure according to claim 6.

Images