JP2007275979A - Welding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection welding method which can suppress fluctuation of compressing amount, when the projection is compressed. <P>SOLUTION: In the projection welding, a projection 30c on a first member 30 having the protrusion type projection 30c is brought into contact with a second member 35b facing the first member 30 each other. Then the first member 30 and the second member 35b are joined by applying vertical pressure on the contacting face to compress the projection 30c while conducting electricity to the contacting face. In the process, a stopper 30d is arranged to limit access of the second member 35b to the first member after the projection 30c is compressed to a designated amount. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projection welding method.

  Projection welding is known as the following welding method.

  One projection object is provided with a projection called a projection, and this projection is brought into contact with the other object. Then, by applying a large current and applying pressure to the contact surface, the projection is crushed and the joining member is joined. This is the principle of projection welding.

  On the other hand, the pressure sensor of patent document 1 is known as a product manufactured by projection welding. This pressure sensor is provided with a metal diaphragm made of carbon steel such as S15C, SUS or the like inside an aluminum housing, and detects the pressure applied to the metal diaphragm.

  Patent Document 1 discloses the following procedure as a specific method for manufacturing a pressure sensor. First, projection welding is performed on a joint surface between a projection provided in the housing and a ring plate made of carbon steel such as S15C or SUS. Next, a metal diaphragm is stacked on the ring plate, and a ring weld made of carbon steel such as S15C, SUS, or the like is further stacked on the metal diaphragm. Then, laser welding is performed from the ring weld side to weld the ring weld, the metal diaphragm, and the ring plate. Thereby, the metal diaphragm is fixed to the housing via the ring plate.

In laser welding, if the welding objects are not located at the welding focus, the welding objects may not be sufficiently welded. For this reason, it is desirable that the projection is crushed by a predetermined amount during projection welding so that the ring weld is located at a predetermined position.
Japanese Patent Laid-Open No. 2005-221515

  In order not to cause variations in the amount of collapse of the projection, it is necessary to accurately control the current that flows during projection welding. However, in projection welding, since it is necessary to flow a huge amount of current in a short time, it is difficult to accurately control the amount of current.

  In view of the above points, an object of the present invention is to provide a projection welding method that suppresses variation in the amount of crushing when crushing a projection.

  In order to achieve the above object, the invention according to claim 1 is directed to the projection (30c) of the first member (30) having the projection (30c) and the first member (30) facing the first member (30). The two members (35b) are brought into contact with each other, an electric current is passed through the contact surface, and a pressure perpendicular to the contact surface is applied, whereby the projection (30c) is crushed, and the first member (30) and the In the projection welding method for joining the second member (35b), a stopper for suppressing the approach of the second member (35b) to the first member (30) after the projection (30c) has been crushed by a predetermined amount ( 30d) is used.

  In this way, when the projection is crushed by a predetermined amount, the projection is crushed by a predetermined amount by preventing the second member and the first member from approaching each other by the stopper.

  The invention according to claim 2 includes the projection (30c) of the first member (30) including the projection (30c) and the second member (35b) facing the first member (30). The projection (30c) is crushed by causing a current to flow through the contact surface and applying a pressure perpendicular to the contact surface, and the first member (30) and the second member (35b) In the projection welding method for joining together, at least one of the surface of the first member (30) facing the second member (35b) and the surface of the second member (35b) facing the first member (30) In addition, the projection is lower than the projection (30c), and the first member (30) of the second member (35b) after the projection (30c) is crushed by a predetermined amount. Suppressing approach stopper (30d), characterized in that the employed against.

  Thus, by providing a stopper that is a projection lower than the projection on the surface of the first member on the second member side or the surface of the second member on the first member side, the amount of collapse of the projection is less than a predetermined amount. While it is, it does not inhibit crushing. Then, after the projection collapse amount reaches a predetermined amount, the stopper comes into contact with the first member or the second member to suppress the projection collapse.

  The invention according to claim 3 includes the projection (30c) of the first member (30) supported by the first jig (71), the projection (30c), and the first member (30c). 30) and the second member (35b) supported by the second jig (73) is brought into contact with each other, current is passed through the contact surface, and a pressure perpendicular to the contact surface is applied. In the projection welding method in which the projection (30c) is crushed and the first member (30) and the second member (35b) are joined, the projection (30c) and the second member (35b) are in contact with each other. At the time, between the first jig (71) and the second jig (73), between the first jig (71) and the second member (35b), the first member (30 ) And the second jig (73 There is a predetermined gap (74) is more than at least one location between said gap (74), when the projection (30c) has collapsed a predetermined amount, characterized in that it disappears.

  Thus, a gap is provided between the first jig and the second jig, between the first jig and the second member, or between the first member and the second jig. This gap narrows as the projection collapses. Further, this gap disappears when the projection is collapsed by a predetermined amount. When the gap disappears, the first jig and the second jig, or the first jig and the second member, or the first member and the second jig are in contact. After that it will not collapse. That is, the amount of projection collapse can be set to a predetermined amount.

  The invention according to claim 4 is characterized in that the projection (30c) and the stopper (30d) are each formed on a circumference, and each circumference has a common center.

  By forming the projection and the stopper concentrically, the distance between the projection and the stopper becomes constant, so that the first member can stably support the second member.

  The invention according to claim 5 is characterized in that the stopper (30d) is continuously formed on the circumference.

  An annular stopper can be formed by continuously generating the stopper on the circumference. And since it is cyclic | annular, a stopper can contact the perimeter of a 2nd member, and it becomes possible to support a 2nd member stably.

  The invention according to claim 6 is characterized in that the stopper (30d) is intermittently formed on the circumference and supports the second member (35b) at at least three points.

  By forming the stopper intermittently on the circumference, the volume of the stopper can be reduced, and the weight can be reduced compared to the case where the stopper is formed in an annular shape.

  The invention according to claim 7 is characterized in that the stopper (30d) and the projection (30c) are formed on different members.

  By forming the stopper and the projection on separate members, it is possible to form a stopper and a projection having the features of each member. For example, if the stopper is formed of a material that is not easily crushed by pressing, and the projection is formed of a material that is easily crushed by pressing, projection welding can be performed with a low pressing force.

  The invention according to claim 8 is characterized in that the stopper (30d) and the projection (30c) are formed on the same member.

  The invention according to claim 9 is characterized in that the energization is stopped before the stopper (30d) contacts the first member (30) or the second member (35b).

  In this way, by stopping energization before the stopper comes into contact with the first member or the second member, it is possible to prevent the stopper from being crushed similarly to the projection.

  The invention according to claim 10 is characterized in that the gap (74) is equal to a collapse amount of the projection (30c).

  Thereby, the amount of collapse of the projection can be adjusted by adjusting the width of the gap.

  The invention according to claim 11 is characterized in that the first member (30) and the second member (35b) are made of different metals.

  Thereby, for example, the first member can be made of a metal resistant to oxidation, and the second member can be made of a lightweight metal.

  The invention according to claim 12 is characterized in that the first member (30) is made of SUS and the second member (35b) is made of aluminum.

  Accordingly, the first member is made of SUS that is resistant to corrosion, and lightweight aluminum can be used for the second member.

  The invention according to claim 13 is characterized in that the first member (30) is made of aluminum, and the second member (35b) is made of SUS.

  Thereby, the first member is made of lightweight aluminum, and the second member can use SUS that is resistant to corrosion.

  The invention according to claim 14 is characterized in that the stopper (30d) has a larger area than the projection (30c) and contacts a member facing the member on which the stopper (30d) is formed.

  Since the contact area is wide, the stopper can support a member that makes stable contact.

  The invention according to claim 15 is characterized in that the stopper (30d) has a smaller area than the projection (30c) and contacts a member facing the member on which the stopper (30d) is formed.

  Thereby, the welding area of a projection can be enlarged and it is possible to perform firm welding.

  The invention according to claim 16 is the welding method when the welding method generates the pressure sensor (S1), wherein the first member is a housing (30), and the second member is a ring plate. (35b), a metal diaphragm (34) is joined to the outer periphery of the ring plate (35b), a ring weld (35a) is joined to the outer periphery of the metal diaphragm (34), and the ring weld (35a) ) Is joined to the case (10), and a portion surrounded by the metal diaphragm (34), the ring weld (35) and the case (10) is defined as a pressure detection chamber (40), and the pressure detection chamber (40) It is a welding method at the time of producing | generating the pressure sensor (S1) by which the said sensing part (20) is arrange | positioned in the inside, It is characterized by the above-mentioned.

  As described above, the ring plate is provided, and after the ring plate is joined to one surface of the housing, the metal diaphragm and the ring weld are arranged on the ring plate so as to join them. Then, by using the stopper to make the projection collapse constant, the joint surface between the ring plate and the housing can be flattened, and the ring plate and the housing can be firmly joined.

  When a metal diaphragm and a ring weld are placed on such a ring plate and joined together, these parts are easily welded because they are made of the same metal material.

  Therefore, even if the metal diaphragm and the housing are made of different metal materials, they can be reliably joined and the sealing performance between them can be ensured.

  The invention according to claim 17 is characterized in that the thickness of the ring plate (35b) is set to 0.3 mm or more.

  The invention according to claim 18 is characterized in that the thickness of the ring plate (35b) is set to 1.0 to 1.5 mm.

  Hereinafter, the best mode for carrying out the present invention will be described using Examples 1 to 3.

[Example 1]
The pressure sensor produced | generated using the projection welding of this invention is demonstrated using FIGS. 1-5. FIG. 1 shows a cross-sectional view of the pressure sensor S1 in the first embodiment, and FIG. 2 shows an enlarged view of the frame A region in FIG. 1 and will be described based on these drawings. In addition, this pressure sensor S1 is applied to what detects the refrigerant | coolant pressure in the refrigerant | coolant piping of the motor vehicle air conditioner mounted, for example.

  As shown in FIG. 1, a connector case 10 as a first case is made by molding a resin such as PPS (polyphenylene sulfide) or PBT (polybutylene terephthalate). It is columnar. A concave portion 11 is formed at one end (the lower end in FIG. 1) of the connector case 10 as the resin case.

  A sensor element 20 as a pressure detecting sensing part is disposed on the bottom surface of the recess 11.

  The sensor element 20 has a diaphragm as a pressure receiving surface on the surface thereof, and converts the pressure received by the diaphragm into an electrical signal by a gauge resistance formed on the surface of the diaphragm, and outputs the electrical signal as a sensor signal. It is a semiconductor diaphragm type.

  The sensor element 20 is integrated with a pedestal 21 made of glass or the like by anodic bonding or the like, and the sensor element 20 is mounted on the connector case 10 by bonding the pedestal 21 to the bottom surface of the recess 11. .

  In addition, a plurality of metal rod-shaped terminals 12 for electrically connecting the sensor element 20 and an external circuit or the like pass through the connector case 10.

  In the first embodiment, the terminal 12 is made of a material in which brass (brass) is plated (for example, Ni plating), and is held in the connector case 10 by being integrally formed with the connector case 10 by insert molding. ing.

  The end of each terminal 12 on one end side (the lower end side in FIG. 1) is disposed so as to protrude from the bottom surface of the recess 11 around the mounting area of the sensor element 20. On the other hand, the end of each terminal 12 on the other end side (the upper end side in FIG. 1) is exposed in the opening 15 on the other end side of the connector case 10.

  One end of each terminal 12 protruding into the recess 11 and the sensor element 20 are connected and electrically connected by a bonding wire 13 such as gold or aluminum.

  Further, a sealing agent 14 made of silicon resin or the like is provided in the recess 11, and the seal agent 14 seals a gap between the base portion of the terminal 12 protruding into the recess 11 and the connector case 10. Yes.

  On the other hand, in FIG. 1, the other end portion (the upper end portion in FIG. 1) side of the connector case 10 is an opening portion 15. The opening portion 15 is connected to the other end side of the terminal 12, for example, a wire harness. This is a connector portion for electrically connecting to the external circuit (such as an ECU of the vehicle) via an external wiring member (not shown).

  That is, the other end side of each terminal 12 exposed in the opening 15 can be electrically connected to the outside by this connector portion. Thus, signal transmission between the sensor element 20 and the outside is performed via the bonding wire 13 and the terminal 12.

  As shown in FIG. 1, a housing 30 as a second case is assembled to one end of the connector case 10. Specifically, the housing 30 is provided with a housing recess 30a, and the housing 30 is assembled to the connector case 10 by inserting one end of the connector case 10 into the housing recess 30a. ing.

  Thus, a casing 100 is formed in which the connector case 10 as the first case and the housing 30 as the second case are assembled together, and the sensor element 20 is provided in the casing 100. It has become.

  The housing 30 is made of a light metal material of the same type as the object to be measured, such as aluminum (Al) or duralumin, and has a pressure introduction hole 31 into which the measurement pressure from the object to be measured is introduced. As described above, the measurement object is, for example, a refrigerant pipe of an automobile air conditioner, and the measurement pressure is a refrigerant pressure in the refrigerant pipe.

  Further, as shown in FIG. 2, a thin metal diaphragm 34 has a ring weld between the front end surface 10a of the connector case 10 and one surface 30b of the housing recess 30a of the housing 30 facing the front end surface 10a of the connector case 10. (Pressing member) 35a and metal diaphragm 34 are disposed in a state of being sandwiched between ring plates 35b thicker than metal diaphragm 34. These are joined together by welding.

  The metal diaphragm 34 is made of a metal such as SUS630, and the ring weld 35a is made of a metal such as SUS316L. The ring plate 35b is preferably made of, for example, SUS material such as SUS316L or carbon steel, but may be made of SUS and Al material or iron and Al material clad material. Further, the thickness of the ring plate 35b may be 0.3 mm or more, but is preferably about 1.0 to 1.5 mm.

  FIG. 3 is a cross-sectional view taken along plane BB in FIG. As shown in FIG. 3, a ring-shaped projection (projection) 30c and a stopper 30d are formed in an annular shape at a portion of one surface 30b of the housing 30 where the ring plate 35b contacts, and the ring plate 35b The projection 30c is welded to the housing 30 by resistance to the entire circumference and supported by the stopper 30d, so that it is hermetically joined to one end of the pressure introduction hole 31.

  As shown in FIG. 1, the end portion on the housing recess 30 a side of the housing 30 is caulked to one end portion of the connector case 10 to form a caulking portion 36, thereby forming the housing 30 and the connector case 10. Are fixed and integrated.

  In the connector case 10 and the housing 30 thus combined, the pressure detection chamber 40 is configured between the concave portion 11 of the connector case 10 and the diaphragm 34 of the housing 30.

  The pressure detection chamber 40 is filled with oil (fluorine oil or the like) that is a pressure transmission medium and is a sealing liquid. That is, the recess 11 is filled with oil so as to cover the electrical connection portions such as the sensor element 20 and the wire 13, and is covered and sealed by the diaphragm 34.

  By constructing such a pressure detection chamber 40, the pressure introduced from the pressure introduction hole 31 is applied to the sensor element 20, the bonding wire 13, and the terminal 12 in the pressure detection chamber 40 via the metal diaphragm 34 and oil. Will be applied.

  In the pressure sensor according to the first embodiment, an annular groove (O-ring groove) 42 is formed on the distal end surface 10 a of the connector case 10 so as to surround the outer periphery of the pressure detection chamber 40. Is provided with an O-ring 43 for hermetically sealing the pressure detection chamber 40.

  The O-ring 43 is made of an elastic material such as silicon rubber, and is pressed between the connector case 10 and the housing 30. Thus, the pressure detection chamber 40 is sealed and closed by the metal diaphragm 34 and the O-ring 43.

  Next, a manufacturing method of the pressure sensor S1 will be described.

  First, the connector case 10 in which the terminal 12 is insert-molded is prepared. The sensor element 20 is bonded and fixed to the concave portion 11 of the connector case 10 via the base 21 using an adhesive made of silicon resin or the like.

  Then, the sealing agent 14 is injected into the recess 11, and the sealing agent 14 is spread to the bottom surface of the recess 11. Here, the injection amount is adjusted so that the sealing agent 14 does not adhere to the surface of the sensor element 20.

  Subsequently, the injected sealing agent 14 is cured. And wire bonding is performed, the one end part of each terminal 12 and the sensor element 20 are connected with the bonding wire 13, and are electrically connected.

  Then, the connector case 10 is arranged with the sensor element 20 side up, and a certain amount of oil made of fluorine oil or the like is injected into the recess 11 from above the connector case 10 by a dispenser or the like.

  4A to 4E and FIGS. 5A to 5C, the ring plate 35b and the ring weld 35a are welded and fixed to the housing 30, and the housing 30 and the connector case 10 after the welding are fixed. The flow of combining the two will be described.

  As shown in FIG. 4A, the ring plate 35 b is pressed from the accommodation recess direction to the projection direction, and the ring plate 35 b is inserted into the accommodation recess 30 a in the housing 30. At this time, since the overall height of the protrusion 30c is higher than the overall height of the stopper 30d, the ring plate 35b contacts the protrusion 30c. At this time, a current is passed between the ring plate 35b and the protrusion 30c. In addition, the time t0 of Fig.5 (a) is a current supply start time. Since the current used for welding is a large current of about 10 kA to 300 kA, the time to reach the target current value is t2 as shown in FIG. 5A, and a slight delay time occurs. On the other hand, since the current flows through the protrusion 30c between t0 and t2, the temperature of the protrusion 30c rises as shown from time t0 to t2 in FIG. 5B. The temperature T1 in FIG. 5B is the lowest temperature at which the protrusion 30c is crushed when the ring plate 35b is pressed. For this reason, after the time t1 when the temperature of the protrusion 30c becomes equal to or higher than T1, the protrusion 30c starts to be crushed as shown in FIG.

  Even after t2, when energization is performed on the protrusion 30c, the temperature of the protrusion 30c is saturated to a constant value as shown at time t3 in FIG. 5B. Further, as shown in FIG. 5A, the energization is stopped at t4 after t3. Thereby, as shown after the time t4 of FIG.5 (b), the temperature fall of the projection part 30c begins. However, even after the energization is stopped (after t4), the protrusion 30c can be crushed while the temperature of the protrusion 30c is equal to or higher than T1.

  As shown in FIG. 4B, t5 in FIGS. 5B and 5C is the time when the ring plate 35b comes into contact with the stopper 30d. At this time, as shown in FIG. 5B, at t5, the temperature of the protrusion 30c is T2 (T2> T1), and the protrusion 30c is in a state where it can be crushed. However, since the ring plate 35b is in contact with the stopper 30d as shown in FIG. 4 (b), the protrusion 30c is not crushed after t5 in FIG. 5 (c). At time t5, since the energization is already stopped, the temperature of the stopper 30d is low and the stopper 30d is not crushed. By using the stopper 30d in this way, the ring plate 35b is resistance-welded to the housing 30 while crushing the protrusion 30c by a predetermined amount.

  Thereafter, the ring weld 35a is disposed on the ring plate 35b as shown in FIG. Next, as shown in FIG. 4D, the ring weld 35a-metal diaphragm 34-ring plate 35b are joined by laser welding or the like from the upper surface side of the ring weld 35a. At this time, since the metal diaphragm 34, the ring weld 35a, and the ring plate 35b are all made of the same metal or a metal that can be bonded, they can be easily bonded.

  Subsequently, as shown in FIG. 4E, the housing 30 is lowered from the top together with the metal diaphragm 34, the ring weld 35a, and the like so as to be fitted to the connector case 10 while keeping the level. And the thing of this state is put into a vacuum chamber, and vacuuming is performed, and the excess air in the pressure detection chamber 40 is removed.

  Thereafter, the pressure detection chamber 40 sealed by the metal diaphragm 34 and the O-ring 43 shown in FIG. 2 is formed by pressing until the front end surface of the connector case 10 and the one surface 30b of the housing 30 are in sufficient contact.

  Finally, the caulking portion 36 is formed by caulking the end portion of the housing 30 to one end side of the connector case 10. Thus, by integrating the housing 30 and the connector case 10, the connector case 10 and the housing 30 are assembled and fixed by the caulking portion 36. In this way, the pressure sensor S1 shown in FIG. 1 is completed.

  A basic pressure detection operation of the pressure sensor S1 will be described.

  For example, the pressure sensor S1 attaches the housing 30 to an appropriate position of a refrigerant piping system of an air conditioner in a vehicle. Then, the pressure in the pipe is introduced into the pressure sensor S <b> 1 from the pressure introduction hole 31 of the housing 30.

  Then, the introduced pressure is applied from the metal diaphragm 34 to the surface of the sensor element 20, that is, the pressure receiving surface, through the oil in the pressure detection chamber 40. And the electrical signal according to the applied pressure is output from the sensor element 20 as a sensor signal.

  This sensor signal is transmitted from the sensor element 20 to the external circuit via the wire 13 and the terminal 12, and the refrigerant pressure in the refrigerant pipe is detected. In this way, pressure detection in the pressure sensor S1 is performed.

  As described above, in the pressure sensor S1 of the first embodiment, when the ring plate 35b and the protrusion 30c provided on the housing 30 are resistance-welded, the collapse amount of the protrusion 30c becomes a predetermined amount. Sometimes, the ring plate 35 b comes into contact with the stopper 30 d provided on the housing 30. Thereby, it can suppress that the projection part 30c is crushed more than predetermined amount, and can make the amount of crushing of the projection part 30c predetermined amount. As a result, the ring plate 35b can be disposed at a predetermined position with respect to the housing 30, so that the metal diaphragm 34 and the ring weld 35a stacked on the ring plate 35b can also be disposed at the predetermined position.

  Hereinafter, an effect obtained when the amount of collapse of the protrusion 30c becomes a predetermined amount will be described. As a first effect, since the ring weld 35a exists at a predetermined position, as shown in FIG. 4D, when performing laser welding from the upper surface side of the ring weld 35a, the laser focus is accurately set. be able to.

  As a second effect, since the ring plate 35b is supported by the stopper 30d in addition to the protrusion 30c, the ring plate 35b can be firmly fixed to the housing 30.

[Example 2]
Example 2 will be described with reference to FIG. The second embodiment differs from the first embodiment in that a stopper 35d is provided on the jig. In addition, about the structure equivalent to above-mentioned Example 1, the code | symbol similar to Example 1 is attached | subjected and description in this Example 2 is abbreviate | omitted.

  6A to 6D show a flow of projection welding the ring plate 35b to the housing 30. FIG. As shown in FIG. 6A, with the housing 30 fixed to the housing fixing jig 71, the ring plate 35b is inserted into the housing 30, and the ring plate 35b is brought into contact with the protrusion 30c.

  And as shown in FIG.6 (b), the positioning jig 72 is passed through the ring plate 35b, and the shift | offset | difference to the extending direction of the ring plate 35b is suppressed.

  Next, as shown in FIG. 6C, the pressing jig 73 is inserted into the gap between the housing 30 and the positioning jig 72 to press the ring plate 35b toward the housing and to energize the ring plate 35d. At this time, since the ring plate 35d is in contact with the protrusion 30c, it can be energized. The protrusion 30 c generates heat by energization after this FIG. 6C and is crushed by the pressing of the pressing jig 73. As shown in FIG. 6C, the fixing jig 71 and the pressing jig 73 are opposed to each other with the clearance 74 interposed therebetween. And like the frame C, a part of the fixing jig 71 and the pressing jig 73 sandwiching the clearance 74 becomes the stopper 30d.

  After energization and pressurization after FIG. 6C, the clearance 74 between the fixing jig 71 and the pressing jig 73 disappears as shown in FIG. 6D, and both jigs come into contact with each other. For this reason, after FIG.6 (d), even if it supplies with electricity and pressurization, the projection part 30c is not crushed.

  As described above, the clearance 74 is provided between the jigs, and the protrusion 30c can be crushed by a predetermined amount using the clearance 74.

Example 3
Example 3 will be described with reference to FIG. The third embodiment is different from the second embodiment in that the caulking portion 36 of the housing 30 has a stopper function. In addition, about the structure equivalent to each above-mentioned Example, the code | symbol similar to each Example is attached | subjected and description in this Example 3 is abbreviate | omitted.

  7A and 7B show a flow of projection welding the ring plate 35b to the housing 30. FIG. As shown in FIG. 7A, the housing 30 is fixed to a fixing jig 71, and the ring plate 35b is in contact with the protruding portion 30c, and the positioning jig 72 shifts the ring plate 35b in the extending direction. It is in a suppressed state. Further, FIG. 7A is a diagram when the pressing jig 73 presses the ring plate 35b in the direction of the protruding portion 30c and starts energization as in the second embodiment. At this time, a slight clearance 74 exists between the pressing jig 73 and the caulking portion 36 of the housing 30. And like the frame D, a part of the crimping portion 36 and the pressing jig 73 sandwiching the clearance 74 becomes the stopper 30d.

  When further pressing and energization are performed from the state of FIG. 7A, the protrusion 30 c is crushed and the ring plate 35 b approaches the housing 30. Thereafter, as shown in FIG. 7B, the caulking portion 36 of the housing comes into contact with the pressing jig. For this reason, after FIG.7 (b), even if it supplies with electricity and pressurization, the projection part 30c is not crushed.

  As described above, in addition to the method of providing the clearance between the jigs as in the second embodiment, the protrusion 30c can be positioned even if the clearance 74 between the protruding part such as the caulking part 36 of the housing 30 and the jig is used. Only a fixed amount can be crushed.

  The caulking portion 36 can fix the housing 30 and the connector case 10 by fixing the connector case 10 and the like to the housing 30 in the subsequent process of FIG. .

[Other Examples]
The stopper 30d of Example 1 described above was ring-shaped (annular) located on the inner circumference of the protrusion 30c. However, the stopper 30d may be a ring positioned outside the circumference of the protrusion 30c, or only a part of the ring may be a stopper as shown in FIG. Moreover, since the stopper 30d supports the ring plate 35b, it is preferable that the stopper 30d is on a concentric circle having the same center as the ring-shaped protrusion 30c. However, even if the stopper is located at a place other than the same concentric circle as the protrusion 30c, the effect of preventing the protrusion 30c from being crushed by a predetermined amount or more and the effect of supporting the ring plate 35b can be achieved. it can.

  Further, either the area of the protrusion 30c on the ring plate side or the area of the stopper 30d on the ring plate side may be larger. When the area on the protrusion side is larger than the area on the stopper side, the ring plate 35b is welded in a wide range. On the other hand, when the area on the stopper side is larger than the area on the protrusion side, the ring plate 35b is supported in a wide area. As a result, the ring plate 35b is stably supported, and the ring plate 35b can be prevented from approaching to a predetermined distance or less.

  In Example 2 and Example 3 described above, energization to the protrusion 35c is performed until the stopper 35d functions, that is, until the clearance 74 disappears. However, as in the first embodiment, before the stopper 35d functions, that is, before the clearance 74 disappears, the energization to the protrusion 35c is terminated, and until the stopper 35d functions until the stopper 35d functions. If the projecting portion 35c is crushed by the residual heat, projection welding can be performed without wasteful energization.

It is sectional drawing of pressure sensor S1 shown in Example 1. FIG. FIG. 2 is an enlarged view in a frame A of FIG. 1 shown in the first embodiment. It is sectional drawing in the BB surface of FIG. 1 shown in Example 1. FIG. 4 is an enlarged cross-sectional view of each step shown in Example 1, FIG. 4A is a state in which the ring plate 35b is in contact with the protrusion 30c, FIG. 4B is a state in which the ring plate 35b is in contact with the stopper 30d, 4C shows a state in which the metal diaphragm 34 and the ring weld 35a are overlapped on the ring plate 35b, and FIG. 4D shows a state in which the ring plate 35b, the metal diaphragm 34, and the ring weld 35a are placed in the state shown in FIG. 4C. FIG. 4E shows a state after laser welding, and shows a state before the housing 30 on which the metal diaphragm 34 generated in FIG. 4D is fixed and the connector case 10 are overlapped. FIG. 5A is a diagram illustrating a time-series change in current value, temperature, and collapse amount in each process shown in Example 1, and FIG. 5A is a time-series change in a current value energized to the protrusion 30c and the ring plate 35b. 5 (b) shows a time-series change in the temperature of the protrusion 30c, and FIG. 5 (c) shows a time-series change in the collapse amount of the protrusion 30c. FIG. 6A is an enlarged cross-sectional view of each process shown in the second embodiment, and FIG. 6A is a diagram illustrating a state in which the housing 30 is fixed to the fixing jig 71 and the ring plate 35b is in contact with the protruding portion 30c. Is a state in which the positioning jig 72 is set on the ring plate 35b, FIG. 6C is a state in which the pressing jig 73 is in contact with the ring plate 35b, and FIG. This is a state in which the clearance 74 is lost due to contact. FIG. 7A is an enlarged cross-sectional view of each process shown in Example 3. FIG. 7A shows a state in which the pressing jig 73 is in contact with the ring plate 35b, and FIG. 7B shows the caulking portion 36 in the pressing jig 73. This is a state in which the clearance 74 is lost due to contact. It is a figure shown in another Example, and represents the state in which the stopper 30d is produced | generated intermittently from the same viewpoint as FIG.

Explanation of symbols

S1 Pressure sensor 10 Connector case 11 Recess 12 Terminal 13 Bonding wire 14 Sealing agent 15 Opening 20 Sensor element 21 Base 30 Housing 30a Housing recess 30b One surface 30c Protrusion 30d Stopper 31 Pressure introduction hole 34 Metal diaphragm 35a Ring weld 35b Ring plate 36 Caulking part 40 Pressure detection chamber 42 Annular groove (O-ring groove)
43 O-ring 71 Fixing jig 72 Positioning jig 73 Pressing jig 74 Clearance 100 Casing

Claims (18)

The projection (30c) of the first member (30) including the projection-like projection (30c) is brought into contact with the second member (35b) facing the first member (30), and current is passed through the contact surface. In addition, in the projection welding method of crushing the projection (30c) by applying a pressure perpendicular to the contact surface, and joining the first member (30) and the second member (35b),
A projection welding method, wherein a stopper (30d) is used to suppress the approach of the second member (35b) to the first member (30) after the projection (30c) is crushed by a predetermined amount. The projection (30c) of the first member (30) including the projection-like projection (30c) is brought into contact with the second member (35b) facing the first member (30), and current is passed through the contact surface. In addition, in the projection welding method of crushing the projection (30c) by applying a pressure perpendicular to the contact surface, and joining the first member (30) and the second member (35b),
From the projection (30c) to at least one of the surface of the first member (30) facing the second member (35b) and the surface of the second member (35b) facing the first member (30). And a stopper (30d) that suppresses the approach of the second member (35b) to the first member (30) after the projection (30c) is crushed by a predetermined amount. Projection welding method. The projection (30c) is provided, and the projection (30c) of the first member (30) supported by the first jig (71) is opposed to the first member (30) and the second jig is supported. The projection (30c) is crushed by bringing the second member (35b) supported by the tool (73) into contact, causing a current to flow through the contact surface, and applying a pressure perpendicular to the contact surface, In the projection welding method for joining the first member (30) and the second member (35b),
When the projection (30c) and the second member (35b) contact each other, the first jig (71) and the first jig (71) are interposed between the first jig (71) and the second jig (73). There is a predetermined gap (74) in at least one place between the second member (35b) and the first member (30) and the second jig (73).
The projection welding method according to claim 1, wherein the gap (74) disappears when the projection (30c) is crushed by a predetermined amount. The projection (30c) and the stopper (30d) are each formed on a circumference,
The projection welding method according to claim 1, wherein each circumference has a common center. The projection welding method according to claim 4, wherein the stopper (30d) is continuously formed on the circumference. The projection welding method according to claim 4, wherein the stopper (30d) is intermittently formed on the circumference and supports the second member (35b) at at least three points. 7. The projection according to claim 1, wherein the stopper (30d) and the projection (30c) are formed on different members. Welding method. The projection according to claim 1, wherein the stopper (30 d) and the projection (30 c) are formed on the same member. Welding method. The energization is stopped before the stopper (30d) contacts the first member (30) or the second member (35b). The projection welding method described in 1. The projection welding method according to claim 3, wherein the gap (74) is equal to a collapse amount of the projection (30c). The projection welding method according to any one of claims 1 to 10, wherein the first member (30) and the second member (35b) are made of different metals. The projection welding method according to any one of claims 1 to 11, wherein the first member (30) is made of SUS, and the second member (35b) is made of aluminum. The projection welding method according to any one of claims 1 to 11, wherein the first member (30) is made of aluminum, and the second member (35b) is made of SUS. The said stopper (30d) is a larger area than the said projection (30c), and contact | connects the member which opposes the member in which this stopper (30d) is formed, or Claim 2 or Claim. The projection welding method according to any one of claims 4 to 9 or claims 11 to 13. The said stopper (30d) is an area narrower than the said projection (30c), and contacts the member which opposes the member in which this stopper (30d) is formed, or Claim 2 or Claim, The projection welding method according to any one of claims 4 to 9 or claims 11 to 13. The welding method is a welding method when generating the pressure sensor (S1),
The first member is a housing (30);
The second member is a ring plate (35b),
A metal diaphragm (34) is joined to the outer periphery of the ring plate (35b),
A ring weld (35a) is joined to the outer periphery of the metal diaphragm (34),
The ring weld (35a) is joined to the case (10),
A portion surrounded by the metal diaphragm (34), the ring weld (35) and the case (10) is defined as a pressure detection chamber (40), and the sensing unit (20) is disposed in the pressure detection chamber (40). The projection welding method according to any one of claims 1 to 15, wherein the projection welding method is a welding method for generating a pressure sensor (S1). The projection welding method according to claim 16, wherein a thickness of the ring plate (35b) is set to 0.3 mm or more. The projection welding method according to claim 16, wherein a thickness of the ring plate (35b) is set to 1.0 to 1.5 mm.

Images