Ultrasonic joining jig, ultrasonic joining device and manufacturing method for contact device

Abstract

To provide a technique that performs ultrasonic joining while protecting an opening / closing surface of a contact, in joining a contact in a contact device to a pedestal by ultrasonic joining.SOLUTION: An ultrasonic joining jig, which is used for joining a contact in a contact device to a pedestal by ultrasonic joining, comprises a groove extending in a first direction, which has a bottom surface that is parallel to an opening / closing surface positioned at the opposite side of a joining surface that is joined to the pedestal in the contact and a first inclined surface and a second inclined surface which are inclined with respect to the bottom surface and whose cross section in a surface perpendicular to the first direction is formed in a trapezoidal shape. In a joining step, the bottom surface separates from the contact, and in the joining step, the first inclined surface and the second inclined surface respectively contact the contact.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an ultrasonic bonding jig, an ultrasonic bonding device, and a method for manufacturing a contact device. [Background technology]

[0002] Patent Document 1 discloses a method for manufacturing a contactor in which pressure is applied to the contact point toward the base metal and ultrasonic vibration is applied. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 175030 Summary of the Invention [Problem to be solved by the invention]

[0004] In contact devices with contacts, such as electromagnetic switches, relays, and circuit breakers, the contacts are joined to a base. If there is, for example, a protrusion on the surface where the contact comes into contact with another contact, an arc may be generated that concentrates on the protrusion when the contact separates. If an arc is generated that concentrates on the protrusion, the contact will wear out quickly. Therefore, when joining the contact to the base, it is desirable to ensure that the surface where the contact comes into contact with the other contact is flat.

[0005] The present disclosure provides a technique for ultrasonically bonding a contact in a contact device to a base while protecting the opening and closing surfaces of the contact. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, there is provided an ultrasonic bonding jig used when ultrasonically bonding a contact and a base in a contact device, the ultrasonic bonding jig comprising a groove extending in a first direction, the groove having a bottom surface parallel to an opening / closing surface located opposite a bonding surface of the contact that bonds with the base, and first and second inclined surfaces inclined relative to the bottom surface, the groove having a trapezoidal cross section in a plane perpendicular to the first direction, the bottom surface being spaced apart from the contact during the bonding process, and the first and second inclined surfaces each contacting the contact during the bonding process. [Effects of the Invention]

[0007] According to the ultrasonic joining jig of the present disclosure, when the contacts of a contact device are ultrasonically joined to a base, the opening and closing surfaces of the contacts can be protected. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a side view illustrating the ultrasonic joining jig according to this embodiment. [Figure 2] FIG. 2 is a bottom view illustrating the ultrasonic joining jig according to this embodiment. [Figure 3] FIG. 3 is a side view illustrating a contactor in which a contact point is joined to a base by the ultrasonic joining jig according to this embodiment. [Figure 4] FIG. 4 is a side view illustrating a contact point joined to a base by the ultrasonic joining jig according to this embodiment. [Figure 5] FIG. 5 is a flow diagram illustrating a joining method using the ultrasonic joining jig according to this embodiment. [Figure 6] FIG. 6 is a diagram illustrating a joining method for joining a contact point to a base using the ultrasonic joining jig according to this embodiment. [Figure 7] FIG. 7 is a diagram illustrating a joining method for joining a contact point to a base using the ultrasonic joining jig according to this embodiment. [Figure 8] FIG. 8 is a diagram illustrating a joining method for joining a contact point to a base using the ultrasonic joining jig according to this embodiment. [Figure 9] FIG. 9 is a diagram illustrating a joining method for joining a contact point to a base using the ultrasonic joining jig according to this embodiment. [Figure 10] FIG. 10 is a schematic diagram of an ultrasonic bonding device equipped with the ultrasonic bonding jig according to this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Note that, in the description of the specification and drawings relating to each embodiment, components having substantially the same or corresponding functional configurations may be designated by the same reference numerals, and redundant description may be omitted. Furthermore, to facilitate understanding, the scale of each part in the drawings may differ from the actual scale.

[0010] In the directions of parallel, right-angle, orthogonal, horizontal, vertical, up-down, left-right, front-back, etc., deviations are permitted to the extent that they do not impair the effects of the embodiments. The shape of the corners is not limited to right angles and may be rounded. Parallel, right-angle, orthogonal, horizontal, and vertical may include approximately parallel, approximately right-angle, approximately orthogonal, approximately horizontal, and approximately vertical, respectively.

[0011] For example, "substantially parallel" means that even if two lines or two surfaces are not completely parallel to each other, they can be treated as parallel as long as it is within the range of manufacturing tolerance. As with "substantially parallel," "substantially right angle," "substantially perpendicular," "substantially horizontal," and "substantially vertical" are also intended to fall under the respective terms as long as the relative position of the two lines or surfaces is within the range of manufacturing tolerance.

[0012] An ultrasonic bonding jig according to this embodiment will be described. The ultrasonic bonding jig according to this embodiment is an ultrasonic bonding jig used when ultrasonically bonding a contact and a base in a contact device. The ultrasonic bonding jig according to this embodiment has a groove with a trapezoidal cross section, which has a bottom surface parallel to the opening and closing surface located opposite the bonding surface of the contact that bonds to the base, and first and second inclined surfaces inclined relative to the bottom surface. The bottom surface of the groove in the ultrasonic bonding jig according to this embodiment is separated from the contact during the bonding process. Furthermore, each of the first and second inclined surfaces of the groove in the ultrasonic bonding jig according to this embodiment comes into contact with the contact during the bonding process.

[0013] The ultrasonic bonding jig according to this embodiment will be described in detail with reference to the drawings. Fig. 1 is a side view illustrating an ultrasonic bonding jig 100, which is an example of the ultrasonic bonding jig according to this embodiment. Fig. 2 is a bottom view illustrating the ultrasonic bonding jig 100, which is an example of the ultrasonic bonding jig according to this embodiment.

[0014] For ease of explanation, the drawings have a virtual three-dimensional coordinate system (XYZ Cartesian coordinate system) consisting of mutually orthogonal X, Y, and Z axes (XYZ axes). For coordinate axes perpendicular to the paper surface of the drawings, a cross in a circle indicates that the coordinate axis is pointing into the paper surface.

[0015] However, this coordinate system is defined for the purpose of explanation and does not limit the posture of the ultrasonic joining jig and the like according to this embodiment.

[0016] [Ultrasonic joining jig 100] The ultrasonic bonding jig 100 is used when ultrasonically bonding a contact to a base in a contact device having contacts, such as an electromagnetic switch, relay, or circuit breaker. The ultrasonic bonding jig 100 comes into contact with the contact. With the ultrasonic bonding jig 100 in contact with the contact, the ultrasonic bonding device applies pressure to the ultrasonic bonding jig 100 in the -Z direction along the Z axis, thereby pressing the contact against the base. The ultrasonic bonding device also applies ultrasonic vibration in the X axis direction while pressing the ultrasonic bonding jig 100 against the contact. For example, the ultrasonic bonding device generates ultrasonic waves of 10 to 100 kHz while pressing the ultrasonic bonding jig 100 against the contact.

[0017] The ultrasonic joining jig 100 is made of, for example, hardened carbon steel.

[0018] The ultrasonic bonding jig 100 has, on the side facing the contact point, lower surfaces 100A, 100C, and 100E which extend along the X-axis and Y-axis directions and are parallel to the XY plane. The ultrasonic bonding jig 100 also has inclined surfaces 100B and 100D which are inclined relative to the bottom surface 100C.

[0019] The ultrasonic bonding jig 100 is provided with a groove 100g that is formed by an inclined surface 100B, a bottom surface 100C, and an inclined surface 100D along the X-axis direction and the Z-axis direction, and has a trapezoidal cross section parallel to the ZX plane.

[0020] In other words, trapezoidal grooves 100g are machined along the Y-axis direction on the side facing the contact points of the ultrasonic joining jig 100. The cross-sectional shape of the grooves 100g is an isosceles trapezoid.

[0021] In the process of joining the contacts and the base using the ultrasonic joining jig 100, the inclined surfaces 100B and 100D of the ultrasonic joining jig 100 come into contact with the contacts. Then, in the process of joining the contacts and the base using the ultrasonic joining jig 100, the ultrasonic joining jig 100 grips two peripheral sides of the opening and closing surfaces of the contacts.

[0022] The upper surface 100F is connected to, for example, a drive unit in an ultrasonic bonding device.

[0023] Here, a contactor in which a contact used in a contact device is joined to a base will be described. Fig. 3 is a side view illustrating a contactor 1 in which a contact 10 is joined to a base 20 by an ultrasonic joining jig 100, which is an example of the ultrasonic joining jig according to this embodiment.

[0024] The contactor 1 comes into contact with or separates from other contactors. More specifically, the contact points 10 of the contactor 1 come into contact with or separate from the contact points of other contactors.

[0025] The contact 1 includes a contact point 10 and a base 20. The contact point 10 is joined to the base 20 by ultrasonic bonding using an ultrasonic bonding jig 100.

[0026] The contact 10 comes into contact with or separates from the contacts of other contacts. The contact 10 is formed of a metal whose main component is, for example, silver or copper. Depending on the application, the contact 10 may contain various metal elements, oxides, carbides, etc. added to silver or copper.

[0027] The contacts 10 are, for example, silver contacts, silver zinc oxide contacts, silver cadmium oxide contacts, silver tin oxide contacts, silver bismuth oxide contacts, silver indium oxide contacts, or silver indium tin oxide contacts.

[0028] A description will be given of the shape of the contact 10 before it is joined to the base 20. Fig. 4 is a side view illustrating the contact 11 joined to the base 20 by an ultrasonic joining jig 100, which is an example of the ultrasonic joining jig according to this embodiment.

[0029] Before joining, the contact 11 has a rectangular shape in a plane parallel to the ZX plane. The contact 11 has dimensions of, for example, 7.3 mm×7.7 mm×1.5 mm.

[0030] The surface of contact 11 on the +Z side is opening / closing surface 11A. Opening / closing surface 11A is the surface that comes into contact with the contact of another contact. The surface opposite opening / closing surface 11A is the joining surface 11B that joins with base 20.

[0031] The base 20 supports the contact 10. The base 20 is made of, for example, a metal containing copper as a main component. The base 20 is made of, for example, oxygen-free copper (C1020). The base 20 may be plated with a thickness of several micrometers, for example, tin plating.

[0032] In the contactor 1 in which the contact 10 is joined to the base 20, the contact 10 has inclined surfaces 10S1 and 10S2 whose shapes respectively imitate the inclined surfaces 100B and 100D of the ultrasonic joining jig 100 that come into contact with the contact 10 during the joining process. Furthermore, in the contactor 1 in which the contact 10 is joined to the base 20, the open / close surface 10A does not come into contact with the bottom surface 100C of the ultrasonic joining jig 100. In other words, the open / close surface 10A is protected during the joining process. Therefore, the open / close surface 10A maintains the state of the open / close surface 11A of the contact 11 before processing and remains flat.

[0033] Returning to Fig. 1, the shape of the groove 100g in the ultrasonic joining jig 100 will be described. As shown in Fig. 1, the lengths along the X-axis direction of the lower surface 100A, the inclined surface 100B, the bottom surface 100C, the inclined surface 100D, and the lower surface 100E are designated as a, b, c, b, and a, respectively. Also, the length along the Z-axis direction from the lower surface 100A or the lower surface 100E to the bottom surface 100C is designated as e. The angle formed between the inclined surface 100B and the bottom surface 100C is designated as g.

[0034] The shape of groove 100g is such that length c of bottom surface 100C along the X-axis direction, i.e., the upper base of the trapezoidal shape, is equal to or less than the length along the X-axis direction at the contact point, for example, d in Figure 4. Also, length c+2b between lower surface 100A and lower surface 100E, i.e., the lower base of the trapezoidal shape, is equal to or greater than the length along the X-axis direction at the contact point, for example, d in Figure 4. Expressed as an equation, b, c, and d satisfy Equation 1.

[0035] c ≦ d ≦ c + 2b (Formula 1)

[0036] If b, c, and d fall outside the ranges shown in Equation 1, contact point 11 cannot contact groove 100g. In other words, c, which is the length of the upper base of the trapezoidal shape of groove 100g, is shorter than d, which is the width of contact point 11. Also, c+2b, which is the length of the lower base of the trapezoidal shape of groove 100g, is longer than d, which is the width of contact point 11.

[0037] Furthermore, it is desirable that the length e of the groove 100g in the Z-axis direction is equal to or less than half the height at the contact point, for example, f in Fig. 4. Expressed as an equation, e and f satisfy Equation 2.

[0038] e ≦ 0.5 f (Formula 2)

[0039] The angle g formed between the inclined surface 100B and the bottom surface 100C may be within a range of 135±30 degrees. Also, the angle g formed between the inclined surface 100B and the bottom surface 100C may be within a range that satisfies Expression 3.

[0040] 91 degrees < g < 130 degrees (Formula 3)

[0041] In other words, the angle g formed by the bottom surface 100C and each of the inclined surfaces 100B and 100D is greater than 91 degrees and less than 130 degrees.

[0042] Each of the inclined surfaces 100B and 100D may be knurled to prevent the members from slipping during the joining process.

[0043] If the angle g deviates from the range shown in Equation 3, slippage occurs due to the ultrasonic vibration during the joining process. If slippage occurs due to the ultrasonic vibration during the joining process, it becomes difficult for the ultrasonic joining jig 100 to grip the contacts. If the ultrasonic joining jig 100 cannot grip the contacts, the contacts and the base may not be ultrasonically joined, or a joining failure may occur.

[0044] If deformation of the ends of the components after ultrasonic bonding is acceptable, the smaller the angle g is within the range shown in Equation 3, the more effectively slippage can be suppressed.

[0045] Furthermore, for example, the ultrasonic joining jig according to this embodiment may be provided with a dimension adjustment mechanism that allows the length c shown in FIG. 1 to be adjusted by tightening a screw or the like so as to accommodate various lengths of members to be joined.

[0046] Next, a bonding method using the ultrasonic bonding jig according to this embodiment will be described. The bonding method using the ultrasonic bonding jig according to this embodiment is a method carried out in a manufacturing method of a contact device. In other words, the bonding method using the ultrasonic bonding jig according to this embodiment is carried out as part of a manufacturing method of a contact device. The steps included in the bonding method using the ultrasonic bonding jig according to this embodiment will be described. FIG. 5 is a flow diagram illustrating a bonding method using an ultrasonic bonding jig 100, which is an example of the ultrasonic bonding jig according to this embodiment. The following description will explain a method of manufacturing a contactor 1 by bonding a contact 10 to a base 20. Each of FIGS. 6 to 9 is a diagram illustrating a bonding method for bonding a contact 10 to a base 20 using the ultrasonic bonding jig 100, which is an example of the ultrasonic bonding jig according to this embodiment.

[0047] (Step S10) First, the base 20 is placed on the anvil 101. Figure 6 is a diagram showing the state in which the base 20 is placed on the anvil 101.

[0048] The base 20 is placed on the placement surface 101A of the anvil 101. Note that the placement surface 101A may be knurled, for example, to hold the base 20 in place during the joining process.

[0049] (Step S20) Next, the contact 11 to be joined is placed on the upper surface 20A of the base 20. In other words, the contact 11 is arranged on the upper surface 20A, which is one surface of the base 20. Fig. 7 is a diagram showing the state in which the contact 11 is placed on the base 20. That is, in step S10, the contact 11 in the contact device is placed on the base 20 to be joined.

[0050] The contact 11 is placed on the upper surface 20A of the base 20 placed on the anvil 101. The contact 11 is placed at a predetermined position on the upper surface 20A.

[0051] The contact 11 is in the delivered state before joining. That is, in Fig. 7, the contact 11 has a rectangular cross section in side view. More specifically, in Fig. 7, the cross section cut along a plane parallel to the ZX plane is rectangular.

[0052] (Step S30) Next, the ultrasonic joining jig 100 is pressed against the contact 11 and vibrated. In other words, the ultrasonic joining jig 100 and the contact 11 are brought into contact with each other, and a predetermined load is applied. Fig. 8 is a diagram showing a state in which the ultrasonic joining jig 100 is being vibrated while being pressed against the contact 11.

[0053] The ultrasonic bonding jig 100 vibrates in the direction indicated by arrow B while being pressed in the direction indicated by arrow A. As the ultrasonic bonding jig 100 vibrates while being pressed in the direction indicated by arrow A, the contact point 11 is bonded to the base 20. Furthermore, as the inclined surfaces 100B and 100D of the ultrasonic bonding jig 100 come into contact with the contact point 11, the contacted portions of the contact point 11 are deformed. The deformed contact point 11 is shown as contact point 10.

[0054] The parameters for joining include load, amplitude, and vibration time. These parameters are adjusted as needed to suit the materials and dimensions of the objects to be joined. For example, the load is 1,000 to 3,000 newtons, the vibration amplitude is 50 to 70 micrometers, and the joining time is 0.5 to 3 seconds.

[0055] On the other hand, the bottom surface 100C of the ultrasonic joining tool 100 does not contact the contact 11. In other words, the bottom surface 100C of the ultrasonic joining tool 100 is separated from the contact 11. That is, the bottom surface 100C of the ultrasonic joining tool 100 is separated from the opening / closing surface 10A of the contact 11.

[0056] In other words, in step S30, while the bottom surface 100C is being moved away from the contact point 11, the inclined surfaces 100B and 100D are each brought into contact with and pressed against the contact point 11. Also in step S30, while the inclined surfaces 100B and 100D are each brought into contact with and pressed against the contact point 11, the ultrasonic bonding jig 100 is vibrated to ultrasonically bond the contact point 11 to the base 20.

[0057] Therefore, according to the joining method using the ultrasonic joining jig of this embodiment, the open-close surface 10A is protected during the joining process, and the open-close surface 10A can be maintained in the state before joining. In other words, according to the joining method using the ultrasonic joining jig of this embodiment, the open-close surface 10A does not deform and the joining is completed while it remains flat.

[0058] 9 is a diagram showing a state in which the ultrasonic joining jig 100 has been separated from the contact point 11 after the joining process is completed. The contact point 11 is pressed against the inclined surfaces 100B and 100D of the ultrasonic joining jig 100 while in contact with them, and thereby becomes the contact point 10 on which the inclined surfaces 10S1 and 10S2 are formed.

[0059] The ultrasonic joining jig according to the present embodiment can protect the opening and closing surfaces of the contacts when ultrasonically joining the contacts of a contact device to a base. The ultrasonic joining jig according to the present embodiment can flatten the opening and closing surfaces of the contacts by protecting them during the joining process. Flattening the opening and closing surfaces of the contacts allows the contacts to be joined to the base without impairing the breaking performance of arcs that occur during opening and closing operations in a contact device such as an electromagnetic switch.

[0060] Next, an ultrasonic bonding apparatus including the ultrasonic bonding jig according to this embodiment will be described. Fig. 10 is a schematic diagram of an ultrasonic bonding apparatus 200 including an ultrasonic bonding jig 100, which is an example of the ultrasonic bonding jig according to this embodiment.

[0061] The ultrasonic bonding device 200 is a device that ultrasonically bonds members. The ultrasonic bonding device 200 includes an ultrasonic bonding jig 100 and a driving unit 110. The driving unit 110 vibrates the ultrasonic bonding jig 100 while pressing the objects to be bonded against an anvil 101. For example, as shown in FIG. 8 , the driving unit 110 vibrates the ultrasonic bonding jig 100 in the direction indicated by arrow B while pressing it in the direction of arrow A. The driving unit 110 vibrates the ultrasonic bonding jig 100 in the direction indicated by arrow B while pressing it in the direction of arrow A, thereby vibrating the ultrasonic bonding jig 100 while pressing it against the contact 11. By vibrating the ultrasonic bonding jig 100 while pressing it against the contact 11, the ultrasonic bonding device 200 can ultrasonically bond the contact 11 and the base 20.

[0062] For example, contact devices such as electromagnetic switches use contactors that switch between circuit interruption and conduction. The contactors consist of a contact and a base to which the contact is joined. Generally, the contact and the base are made of different materials. When joining the contact to the base, for example, methods using secondary materials such as brazing, resistance spot welding, mechanical crimping, etc. are used.

[0063] In recent years, from the viewpoint of cost, direct bonding, typically ultrasonic bonding, is often used to bond the contacts and the base.

[0064] On the other hand, when ultrasonic bonding is performed, multiple grooves are sometimes provided on the contact side surface (opening / closing surface) of the base to prevent slippage between the contact and the base when ultrasonic vibrations are applied. For example, to prevent slippage between the base and the anvil when ultrasonic vibrations are applied, a knurled pattern is applied to the end of the anvil on the base side. Also, to prevent slippage between the horn and the contact when ultrasonic vibrations are applied, a knurled pattern is applied to the end of the horn on the contact side.

[0065] When pressure is applied to the base and the contact point, a number of minute protrusions are formed on the anvil-side end face of the base at the portion that comes into contact with the horn.

[0066] Normally, an arc occurs between two opposing contacts. However, when a base metal with multiple tiny protrusions is used in a contact device such as an electromagnetic switch, arcs may also occur between the grooves formed in the base metal that are formed in areas other than the area where the contacts and base metal face each other when the contact device performs an opening operation.

[0067] Furthermore, the arcs described above tend to be concentrated between the tips of minute protrusions formed on one contact and the tips of minute protrusions formed on the other contact, and because the arcs are concentrated at the tips of the minute protrusions, the contacts and base are exposed to the arc for a long period of time, which can accelerate the wear of the contacts and base.

[0068] According to the ultrasonic joining jig of this embodiment, ultrasonic joining not only makes the joining surface strong, but also keeps the open / close surfaces smooth after joining so as not to reduce the arc interruption performance. By keeping the open / close surfaces smooth, the ultrasonic joining jig of this embodiment can extend the life of the contacts.

[0069] The Y-axis direction is an example of a first direction, one of the inclined surface 100B and the inclined surface 100D is an example of a first inclined surface, and the other of the inclined surface 100B and the inclined surface 100D is an example of a second inclined surface.

[0070] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive, and the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0071] 1 contact 10, 11 contacts 10A, 11A opening and closing surface 10S1, 10S2 Slope 20 pedestal 20A top 100 Ultrasonic joining jig 100A, 100E bottom side 100B, 100D sloped surface 100C bottom 100F top surface 100g groove 101 Anvil 101A Mounting surface 110 Drive unit 200 Ultrasonic bonding equipment

Claims

1. An ultrasonic bonding jig used to ultrasonically bond a contact and a base in a contact device, a groove extending in a first direction, the groove having a bottom surface parallel to an opening / closing surface of the contact point opposite a joining surface that joins with the base, and a first inclined surface and a second inclined surface that are inclined relative to the bottom surface, the groove having a trapezoidal cross section in a plane perpendicular to the first direction; the bottom surface is spaced from the contact point during the bonding process; The first inclined surface and the second inclined surface each come into contact with the contact point during a joining process. Ultrasonic joining jig.

2. the length of the upper base of the trapezoidal shape is shorter than the width of the contact point; The length of the lower base of the trapezoidal shape is longer than the width of the contact point. The ultrasonic joining jig according to claim 1 .

3. The angle formed by each of the bottom surface and the first inclined surface and the second inclined surface is greater than 91 degrees and less than 130 degrees. The ultrasonic joining jig according to claim 2 .

4. The ultrasonic joining jig according to any one of claims 1 to 3; a driving unit that vibrates the ultrasonic bonding jig while pressing it against the contact points; Equipped with Ultrasonic bonding equipment.

5. placing the contacts of the contact device on a seat to be joined; a step of ultrasonically bonding the contact to the pedestal by pressing an ultrasonic bonding jig, which has a groove with a trapezoidal cross section, the groove having a bottom surface parallel to the opening / closing surface of the contact located opposite the joining surface of the contact that joins with the pedestal and a first inclined surface and a second inclined surface inclined relative to the bottom surface, against the contact while separating the bottom surface from the contact, with the first inclined surface and the second inclined surface respectively, and vibrating the ultrasonic bonding jig; Including, A method for manufacturing a contact device.

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