JP6445942B2 - Method for supplying cylindrical member, and method for manufacturing spark plug and gas sensor - Google Patents

Description

  The present invention relates to a supply method suitable for supplying a cylindrical member such as a talc ring formed by consolidating talc powder into a cylindrical shape (ring shape), and a spark using the talc ring as a sealing material. The present invention relates to a plug and a method for manufacturing a gas sensor.

  FIG. 9C is a schematic cross-sectional view of an example of a conventionally known spark plug 1. The spark plug 1 has a different-diameter cylindrical metal fitting body 2 having mounting (screw-in) screws on its outer peripheral surface, and a center electrode 3 that is held in a form inserted into the metal fitting body 2 and protrudes at the tip. And the like, and a grounding electrode 7 welded to the tip of the metal fitting body 2 and the like. The spark plug 1 is attached to the engine by a screwing method through a screw of the metal fitting body 2, but has a high degree of sealing performance between the inner peripheral surface of the metal fitting body 2 and the outer peripheral surface of the insulator 5 due to its configuration. Required. Since a high heat resistance is required for the sealing material for carrying this seal, talc 8 has been conventionally used (see FIG. 1 of Patent Document 1). Also, gas sensors (oxygen sensors or the like) used for detecting the concentration of a specific gas attached to the exhaust system of the engine require similar sealing properties, and talc is used in the same manner (see Patent Document 2). In assembling such a spark plug, as shown in FIG. 9-A, the talc 8 has a circular ring shape (or cylinder) after loading and arranging the insulator 5 including the center electrode 3 in the metal fitting body 2. As a talc ring (or talc pipe) 8 formed into a solid shape, it is supplied between the inner peripheral surface of the metal fitting body 2 and the outer peripheral surface of the insulator 5, and then a washer 9 is supplied. Sent to the process. In the next step, as shown in FIG. 9-B, the rear end portion 2b of the metal fitting body 2 is bent inward by the mold 10 and is pushed forward, and the talc ring 8 is crushed and compressed. Thus, the sealing property is maintained. Thereafter, the ground electrode 7 is bent and assembled as a spark plug of FIG. 9-C.

  FIG. 10C is a schematic cross-sectional view of an example of a conventionally known gas sensor (oxygen sensor or the like) 11. Also in the manufacturing and assembly of this, as shown in FIG. 10-A, the inner peripheral surface of the different-diameter cylindrical metal fitting body 12 having mounting screws on the outer peripheral surface, and the sensor element 13 arranged on the inner side thereof. The talc ring (or talc pipe) 8 and the packing 9 are supplied and arranged between the holder 15 and the outer peripheral surface of the holder 15, and sent to the next step. Also in this next step, as shown in FIG. 10-B, the caulking process similar to that described above is performed on the rear end portion 12b of the metal fitting main body 12, and the sealing performance is maintained by compressing the talc ring 8. doing. Thereafter, a cover 18 surrounding the rear end of the element 13 and the terminal fitting at the tip of the lead wire 16 is placed behind the fitting main body 12 and manufactured and assembled as a gas sensor 11 through welding or the like.

  Conventionally, in the process of manufacturing and assembling such a spark plug or gas sensor, in order to supply the talc ring to the work in progress, for example, the chuck device is moved toward one side, the talc ring is received, chucked (gripped), A method is adopted in which this is moved (transferred) toward the other side, positioned above the work in process, and dropped and supplied. On the other hand, unlike a metal part, such a talc ring is fragile in nature, and is inherently easily chipped because it is a hollow hollow body. For this reason, such a talc ring includes the end of the ring (cylindrical body) 8 as shown in FIG. 11 until the parts are supplied by various external forces received in the manufacturing process and the unloading process. A part (wall part) K may be lacking in a U-shape or V-shape, or may be broken due to cracking. In addition, when a component is chucked and supplied by a normal method, it may be lost due to a compressive force or the like at the time of chucking (clamping) based on its brittleness.

  On the other hand, such a talc ring, as described above, is provided in the work-in-process and then compressed by a caulking process or the like, so that its sealing performance can be obtained. The ring is strictly quality controlled so as to have a predetermined density and volume. If a talc ring that is missing due to chipping or cracking is supplied and caulking processed as it is, it will cause a deterioration in sealing performance, and the caulking part in the caulking process (after the metal fitting body) This also causes problems such as excessive deformation of the plastic deformation portion at the end.

  In order to eradicate the occurrence of such problems, even if it is a talc ring that has been inspected before supply, supply to the work in progress, chipping, etc. may occur in the handling process until placement, Conventionally, talc rings are inspected not only for the in-process product but also before the caulking process after the supply, whether the talc ring is defective or not (pass / fail). I was forced to do that.

JP 2009-16129 A JP 2005-241468 A

  In this way, when using a talc ring as a sealing material for a spark plug or gas sensor, it is necessary to conduct a re-inspection not only before the supply but also before the caulking process after the supply to the work in progress. This has been a factor in reducing the production efficiency of the product. Moreover, such a talc ring cannot be chucked by strongly pinching it based on its brittleness as described above. Due to this, there may be an error in that there is no empty supply (holding error) in which the talc ring is not actually chucked (held), or there is no component supply itself. From this point of view, conventionally, after the supply process to the work-in-process, and before the caulking process, the pass / fail inspection of the talc ring is indispensable, including the inspection of supply / non-supply. There has been a problem that a great deal of cost is required in terms of inspection equipment and the like.

  The present invention has been made in view of such problems, and in the supply of a cylindrical member such as a talc ring, it is possible to prevent the supply of defective products and empty supply, and to omit the inspection process after the supply. It is an object of the present invention to provide a supply method and to improve the manufacturing and assembly efficiency of the spark plug and the gas sensor by applying the method to the manufacturing and assembly of the spark plug and the gas sensor.

According to the first aspect of the present invention, the cylindrical member is held by adsorbing the outer peripheral surface of the cylindrical member to the chuck surface by evacuating the suction opening that opens on the chuck surface of the vacuum chuck device. In the method of supplying the cylindrical member by releasing the adsorption at the supply position,
The chuck surface of the vacuum chuck device used in the supply method surrounds the entire outer peripheral surface of the cylindrical member, and the entire outer periphery of the cylindrical member has a small gap fit or is not tightened. The suction openings are provided so as to be in close contact with the entire surface, and arranged so as to be distributed over the entire area of the chuck surface facing the outer peripheral surface of the cylindrical member to be adsorbed. It is characterized by that.

In the present invention according to claim 2, when the cylindrical member is adsorbed to the chuck surface by evacuation,
When the degree of vacuum obtained by the evacuation is higher than a predetermined degree of vacuum, it is determined as an acceptable product, and when the predetermined degree of vacuum is not obtained, it is determined as an unacceptable product. The cylindrical member supply method according to claim 1, further comprising a determination method.
In the present invention according to claim 3, when the cylindrical member is adsorbed to the chuck surface by evacuation,
When the degree of vacuum obtained by evacuation is higher than a predetermined degree of vacuum, it is determined as an acceptable product, and when a predetermined reduced pressure is obtained, but when the predetermined degree of vacuum is not obtained, it is determined as an unacceptable product. The cylindrical member supply according to claim 1, further comprising a cylindrical member pass / fail determination method and a holding error determination method for determining when the predetermined pressure reduction cannot be obtained as a holding error. Is the method.
According to a fourth aspect of the present invention, the chuck surface is divided into two chuck claws provided in an opposing arrangement so as to surround the outer peripheral surface of the cylindrical member so as to be sandwiched from both radial sides. It is formed, It is the supply method of the cylindrical member of any one of Claims 1-3 characterized by the above-mentioned.

The present invention described in claim 5 is the method for supplying a cylindrical member according to any one of claims 1 to 4, wherein the cylindrical member is a talc ring.
According to a sixth aspect of the present invention, there is provided a spark plug manufacturing method including the cylindrical member supplying method according to the fifth aspect in a spark plug manufacturing and assembling process.
A seventh aspect of the present invention is a gas sensor manufacturing method comprising the method of supplying a cylindrical member according to the fifth aspect in a manufacturing and assembling process of the gas sensor.

  In the first aspect of the present invention, the chuck surface of the vacuum chuck device used in the supply method surrounds the entire outer peripheral surface of the cylindrical member, and a small gap fit is formed on the entire cylindrical member. The cylindrical member is formed so as to be in close contact with the entire outer peripheral surface without being tightened, and the outer peripheral surface of the cylindrical member is adsorbed and held on the chuck surface by evacuation. Even if it is fragile like a talc ring (pipe), it does not generate a compressive force as in a conventional chuck (hold). Thereby, the occurrence of defects such as chipping of the cylindrical member due to the chuck can be prevented. In addition, since the suction openings for vacuuming provided on the chuck surface are provided in an arrangement that is dispersed throughout the entire area as described above, the cylindrical member is like the talc ring 8 shown in FIG. In addition, in the case where there is a chipping K, the determination of the defect can be facilitated, or the supply of the defective product can be prevented. This is because, in the present invention, if there is such a chip or the like, or if there is a defect in a hole penetrating through the cylindrical wall, the suction opening is not limited to any part of the cylindrical member. This is because the vacuum evacuation (reduced pressure) is hindered and a predetermined degree of vacuum cannot be obtained in the chuck because it is arranged in a distributed manner throughout the entire area. In other words, by providing a gauge (vacuum gauge) in the middle of the piping (vacuum passage) between the vacuum generator and the suction opening, it is easy to pass or fail (accepted or rejected) when chucking. This is because it can be determined.

  If the chuck device used in the present invention is a regular cylindrical member with no chipping, or a cylindrical member with only a minute chipping (hereinafter, also referred to as “accepted product” or “non-defective product”), suction and holding by vacuuming Thus, a predetermined degree of vacuum (pressure reduction) is obtained. On the other hand, in the vacuuming of a cylindrical member having an unacceptable chip (hereinafter also referred to as a rejected product or a defective product), the predetermined vacuum is generated due to the air drawing (inflow) from the chipping or the like. The degree is not obtained. That is, by setting the predetermined degree of vacuum to a predetermined value and setting a pass / fail criterion, it is possible to easily determine a rejected product. The predetermined degree of vacuum may be set based on the degree of vacuum (final degree of vacuum) obtained by pre-evacuation using many types of samples of acceptable and unacceptable products. As described above, according to the present invention, it is possible to easily determine pass / fail in the chucking and holding process at the time of chucking for supplying the cylindrical member. Prevention can be easily achieved. As a result, since it is possible to omit the pass / fail inspection process at the supplier (next process) that has been conventionally performed, the inspection cost can be reduced and the inspection efficiency can be improved.

  As an example in which the suction openings are provided in an arrangement that is distributed over the entire area, a plurality of grooves (long grooves extending long) so as to divide the entire area into a plurality of parts regularly or irregularly. A large number of concave portions at regular or irregular intervals, for example, in parallel arrangement, horizontally, vertically, or diagonally, or in a lattice or mesh pattern. For example, the holes may be provided so as to exist. In addition, what is necessary is just to select and use the thing of appropriate performance and capability from vacuum generators (equipment), such as a vacuum ejector and a vacuum pump, for evacuation. When a vacuum ejector is used, the degree of vacuum (vacuum pressure) can be adjusted by adjusting the flow rate of compressed air supplied for generating a vacuum, for example, with a flow rate adjusting valve (throttle valve) so that a desired suction force can be obtained. ) Can be adjusted. When a vacuum pump is used, the degree of vacuum (vacuum pressure) can be adjusted with a vacuum pressure control valve.

  As is apparent from the above, in the present invention, the degree of vacuum obtained by vacuuming when the cylindrical member is attracted to the chuck surface by vacuuming, as in the invention of claim 2. However, it is preferable to include a pass / fail determination method for the cylindrical member, in which a case where the degree of vacuum is higher than a predetermined degree of vacuum is determined as an acceptable product, and a case where the predetermined degree of vacuum is not obtained is determined as an unacceptable product. Here, the predetermined degree of vacuum may be appropriately set according to the inspection level (severity), the management level, and the like.

  When the cylindrical member is attracted to the chuck surface by evacuation as in the third aspect of the invention, the degree of vacuum obtained by evacuation is higher than a predetermined degree of vacuum. It is determined as an acceptable product, and a predetermined reduced pressure is obtained, but when the predetermined degree of vacuum is not obtained, it is determined as an unacceptable product, and when the predetermined reduced pressure is not obtained, it is determined as a holding error. It is good also as including the determination method of the pass / fail of a cylindrical member, and a holding mistake. In this way, by dividing into three stages of acceptable products, rejected products, and holding mistakes, in addition to defects in the cylindrical member itself, there are causes of defects such as defective loading (delivery) of the cylindrical member to the chuck device. Since it can be discovered, rational process control can be performed, so that manufacturing efficiency can be further improved. That is, when the predetermined pressure reduction cannot be obtained and it is determined that the holding is failed, a holding error signal other than the rejected product that can obtain the predetermined pressure reduction is issued, and an operator's confirmation work, etc. If the process is performed, more rational process management can be performed. Here, the “holding error” is a determination result based on the detection (signal) of the degree of vacuum (about reduced pressure, gauge pressure), so the original “holding error (supply error) is not present in the chuck device. In addition to ")", cylindrical members having large chips or the like among the rejected products are also included in the object.

  The chuck surface of the chuck device used in the present invention only needs to surround and hold the entire outer peripheral surface of the cylindrical member in the circumferential direction, and therefore the chuck surface constituting the chuck device is the outer periphery of the cylindrical member. It may have a shape or structure having an integral cylindrical inner surface corresponding to the surface. However, in such a case, in order to surround the cylindrical member, it is necessary to insert it into the cylindrical inner surface forming the chuck surface along the axis of the cylinder, and at the time of supply to the supply destination, Even if the vacuum is released, it may not be able to fall naturally due to gravity. In such a case, another means such as extrusion is required. For this reason, it is preferable that the chuck surface be divided so as to surround the cylindrical member by sandwiching the outer peripheral surface of the cylindrical member from a plurality of radial directions. More preferably, as in the present invention according to claim 4, the two chucks provided in an opposing arrangement so that the chuck surface surrounds the outer peripheral surface of the cylindrical member so as to be sandwiched from both sides in the radial direction. It is good to be divided into nails. In such a chuck device, since the two chuck claws provided in the opposing arrangement can be driven by a linear drive mechanism, the structure of the chuck device can be simplified.

  The cylindrical member, which is the supply target (object to be chucked) in the present invention, is not limited in its material and the like, but is suitable for supplying a talc ring made of a brittle or brittle material such as being easily chipped. Therefore, by including the above supply method in the manufacture and assembly of the spark plug or gas sensor using this as a sealing material, the sealing efficiency is improved and the manufacturing efficiency is increased by omitting the inspection process. It is done. In addition, the cylindrical member which is a supply object in the present invention is not limited to a cylindrical body, and is not limited to a cylindrical cross-sectional shape including those having an inner surface having polygonal holes. It shall include a member (ring) that has a wide cylindrical shape.

The figure which looked at the chuck | zipper apparatus (except vacuum drawing piping) used in the embodiment which actualized the supply method of the cylindrical member of this invention from the top, and the enlarged view of the principal part (chuck claw part). FIG. 2 is a cross-sectional view taken along a line S1-S1 in FIG. 1 (a view of the chuck surface viewed from the front) and an enlarged view of the chuck surface viewed from the front. The perspective view explaining a chuck nail (chuck surface). FIG. 3 is a cross-sectional view taken along line S3-S3 of FIG. 2, illustrating a slit or the like that forms a suction opening that opens on the chuck surface, and an enlarged view of a main part thereof. 1 is a piping diagram showing an example of a vacuuming pipe including a chuck device and a vacuum ejector. 4A is a view before opening the opposing chuck claw and surrounding the talc ring in FIG. 4, and FIG. 5B is a view when the opposing chuck claw is closed to surround the talc ring. The partially broken top view of B of FIG. The piping diagram which shows one example of the evacuation piping containing a vacuum pump. It is a figure explaining the manufacturing assembly process of a spark plug, Comprising: A is sectional drawing for description which supplied the talc ring in the metal fitting main body with which the insulator containing a center electrode was loaded, B is crimping the rear end of a metal fitting main body. Sectional drawing for explanation which compressed the talc ring, C is a sectional view for explanation of the finished spark plug after bending the ground side electrode. FIG. 7 is a diagram for explaining a manufacturing and assembling process of a gas sensor, wherein A is a sectional view for explanation in which a talc ring is supplied into a metal fitting body in which a holder including a sensor element is loaded, and B is a caulking process of a rear end of the metal fitting body Sectional drawing for explanation which compressed the talc ring, C is a sectional view for explanation of a gas sensor finished product formed by covering a rear cover including lead wires and connecting a terminal fitting to the rear end of the element. The perspective view for description of a talc ring with a chip.

  The embodiment which actualized the supply method of the cylindrical member of the present invention is described in detail, referring to FIGS. In the figure, reference numeral 101 denotes a vacuum chuck device (excluding a vacuum drawing pipe) used in the supply method of this example, and is arranged between a cylindrical member (in this example, a metal fitting body and an insulator in a spark plug, between them) Two chuck claws (a pair of left and right) 110 are provided so as to sandwich the outer peripheral surface of a talc ring (bearing seal) from opposite sides. Each chuck claw 110 is attached to each slider 60 that slides left and right (up and down in FIG. 1) along the linear motion track 55 provided on the base 50 (up and down in FIG. 1). On the other hand, it is fixed via a holding body (holder) 70. The details of the left and right chuck claws 110 (chuck surface suction openings and the like) will be described later, but the outer peripheral surface (the whole) of the talc ring 8 that forms a cylinder is surrounded half by half with the axis of the ring interposed therebetween. In addition, a chuck surface 115 having a semi-cylindrical surface extending so as to open in a semicircle at the upper and lower ends is provided on one flat surface 113 of the rectangular parallelepiped block portion 112 (see FIGS. 1 and 3). ). The chuck claw 110 abuts the flat surfaces (closing surfaces) 113 connected at each edge of the semi-cylindrical surface (half-chucking surface 115), so that the outer peripheral surface ( It is set to surround the whole). Then, it is attached to the holding body 70 by bolting or the like via a flat plate-like mounting substrate portion 117 integrally formed so as to extend upward along the back surface of the chuck surface 115 (see FIG. 4 and the like). ).

  The left and right chuck claws 110, the holding body 70, and the slider 60 have the same shape and structure, and the slider 60 follows the linear motion track 55, and the virtual center line Lk drawn in the middle across both chuck claws 110. (Refer to Fig. 1 and Fig. 4) Setting to move forward at the same speed in the direction of closing each other from the state (open state) holding an appropriate amount of space, and to reverse at the same speed in the direction of opening. Has been. Although the slider 60 is moved back and forth (not shown), in this example, the slider 60 is driven by an air cylinder provided in the base (inside) 50. In this example, when both chuck claws 110 are open in the plan view of the virtual cylindrical space formed by the chuck surfaces 115 (when the talc ring 8 is viewed from the end surface side), the talc ring 8 is the center of the ring. Is positioned so as to be positioned, and the chuck claw 110 is closed so that it is sandwiched from both sides.

  The chuck surface 115 does not have to be tightened on the outer peripheral surface in a state where the talc ring 8 is surrounded. Therefore, the inner diameter Dn of the cylinder formed by both chuck surfaces 115 may be the same as the outer diameter D8 of the talc ring 8. However, in this example, a very small amount (for example, 0.1 mm according to the dimensional variation of the talc ring 8) is made larger than the outer diameter D8. Accordingly, when the pair of chuck claws 110 are closed and the closing surfaces (planes) 113 of the chuck claws 110 forming the close contact with each other to surround the talc ring 8, the outer peripheral surface of the talc ring 8 is Each chuck surface (semi-cylindrical surface) 115 is set so as to be surrounded by a gap fit close to close contact. On the other hand, the height H1 of the semi-cylindrical surface (chuck surface 115) forming the recess forming the chuck surface 115 is equal to or higher than the total height of the talc ring 8 in this example. Thus, when the chuck claw 110 is closed and the talc ring 8 is surrounded, the chuck surface 115 is set so as to surround the entire outer surface (entire surface) of the talc ring 8.

  Such a vacuum chuck device (hereinafter referred to as a chuck device) 101 is integrated with the base 50 and has a predetermined position (a position to receive and chuck the talc ring 8) as a supply source of the talc ring 8. It is assumed that it is attached to a moving means (moving mechanism) (not shown) capable of reciprocating between a predetermined position (a transfer position of a spark plug assembly work product for receiving the talc ring 8) as a supply destination.

  Now, as described above, the chuck surfaces 115 of the left and right chuck claws 110 in this example are concave on one plane 113 of the rectangular parallelepiped block portion 112, and are semi-cylindrical surfaces extending open at a semicircle at the upper and lower ends. However, in this example, a suction opening (evacuation opening) 119 is formed in the chuck surface 115 as follows. That is, as shown in FIGS. 2 to 4 and the like, in this example, the chuck surface 115 forming the semi-cylindrical surface has a chuck surface (semi-cylindrical surface) having a predetermined width (vertical width) at both upper and lower end portions. ) 115, and a plurality of slits 121 (4 in this example) are formed at regular intervals (leaving a semi-cylindrical surface) with a constant groove width in the vertical direction. The slits 121 formed by cutting are provided so as to extend in the circumferential direction to the left and right closing surfaces (planes) 113 at the left and right edges of the semi-cylindrical surface (see FIGS. 1 to 3 and the like). That is, the slit 121 cuts outward (plane 113) from the left and right edges forming the inner diameter Dn when the chuck surface 115 of the semi-cylindrical surface is viewed from the front (see FIGS. 2 and 3). Each of them is formed so as to penetrate toward the back side of the rectangular parallelepiped block portion 112 (see FIGS. 1 and 4).

  Thus, in this example, the suction opening 119 is formed as an end of the slit 121 in the chuck surface 115 (semi-cylindrical surface) over the entire area facing the outer peripheral surface of the talc ring 8 at a predetermined interval in the vertical direction on the chuck surface 115. It is provided to exist in a distributed manner. And as above-mentioned, such a chuck | zipper claw 110 is attached to the holding body 70 by bolting etc. via the flat-shaped attachment board | substrate part 117 extended upwards along the back surface, and a rectangular parallelepiped block site | part The back surface of 112 is brought into close contact with the front surface (planar portion) 73 of the holding body 70 (see FIG. 4 and the like). However, in the front surface 73 of the holding body 70, a portion corresponding to the plurality of slits 121 opened on the back surface of the chuck claw 110 (the rectangular parallelepiped block portion 112) is provided with recesses (spaces) 75, and On the back surface of the holding body 70 corresponding to the recess 75, a screw hole 77 for a tube penetrating toward the recess 75, that is, a screw hole (evacuation port) 77 for vacuuming piping is provided (FIG. 4 etc.). As the vacuum generator, a vacuum pump can be used. In this example, however, the vacuum ejector 130 is provided with a vacuum gauge as shown in the piping diagram of FIG. 133, and the compressed air supply port of the vacuum ejector 130 is an air supply for generating vacuum via a solenoid valve (a solenoid valve for starting evacuation) 136, a throttle valve (not shown), or the like. It is connected to a port 137 and piped to a compressed air source (compressor tank) (not shown). Thereby, the air supply (for example, 0.4 MPa) to the vacuum ejector (for example, the maximum vacuum pressure −88 KPa) 130 is set to be performed at an appropriate supply flow rate. Note that a silencer 139, a filter, and the like may be provided as appropriate.

  Next, a process of supplying the talc ring 8 by evacuating and holding the talc ring 8 and releasing the suction (vacuum breakage) at the supply position using the chuck device 101 of this example will be described. In this example, the left and right sliders 60 are driven at a predetermined position (receiving position) as a supply source of the talc ring 8, and the talc ring 8 is in a state where the chuck pawl 110 is open as shown in FIG. 6A. Is received and positioned at a predetermined center position between the claws 110 by a delivery means (not shown). Then, as shown in FIG. 6B, the claw 110 is closed and the entire outer peripheral surface thereof is surrounded by the chuck surface 115. In this state, one (or both) of the evacuation start solenoid valves 136 held closed is switched on to open. As a result, compressed air is supplied to the vacuum ejector 130, and the air in the slit 121 formed in the closed chuck claws 110 is sucked (air purge) as shown by the broken line arrows in FIG. . By this suction, the outer peripheral surface of the talc ring 8 is attracted to the suction opening 119 of the chuck claw 110 and is attracted to the chuck surface (remaining semi-cylindrical surface) 115 other than the opening 119 by a vacuum action. This vacuuming is set to obtain a predetermined degree of vacuum that can hold the talc ring 8 without dropping. On the other hand, after the chuck device 101 holding the talc ring 8 is moved to a predetermined position as a supply destination by the moving means, the evacuation start electromagnetic valve 136 is closed by switching off. By doing so, the supply of compressed air to the vacuum ejector 130 is stopped and the vacuum is released.

  In this way, in the case of the chuck system of this example, since the compressive force is not generated as in the conventional clamping (clamping) chuck (holding), defects such as chipping of the talc ring 8 due to the chuck are generated. Can be prevented. Moreover, since the suction openings 119 for evacuation provided in the chuck surface 115 are provided in an arrangement that is dispersed throughout the entire area as described above, the talc ring 8 is shown in FIG. Even if such a chip is present in any part, it can be easily determined as a rejected product. This is because evacuation (reduced pressure) is hindered and a predetermined degree of vacuum cannot be obtained regardless of which portion has such a chip.

  More specifically, it is as follows. In this example, when the talc ring 8 is attracted to the chuck surface 115 by evacuation, when including a pass / fail judgment method, for example, the degree of vacuum obtained by evacuation is a predetermined degree of vacuum ( It may be determined that the time when the altitude is higher than −40 kPa) is determined as an acceptable product, and the time when the predetermined degree of vacuum cannot be obtained is determined as an unacceptable product. Then, only when it is determined as “accepted product”, it is sufficient to control the subsequent supply after the adsorption. When it is determined as “failed product”, for example, the process is stopped at that stage. Take control. The control after these judgments will be described below. The above-mentioned predetermined degree of vacuum for distinguishing between “accepted products” and “failed products” includes the talc ring 8 with no chipping, and minute chipping. The degree of vacuum that should be obtained in vacuuming as a passing product based on various acceptable samples for the talc ring 8 that are within the acceptable range or various unacceptable samples for the talc ring 8 with an unacceptable chip Can be obtained by confirming in advance. Then, necessary control may be performed based on a difference in a signal (pressure signal) generated from the vacuum gauge 133 when the predetermined degree of vacuum is obtained and when it is not obtained.

  That is, when a predetermined vacuum degree is obtained by the vacuum gauge 133 and it is determined as “acceptable product”, the chuck device 101 is supplied by the moving means from the suction and holding position based on the signal, for example. It is moved to a predetermined position (position of the work in process of assembling the spark plug). Then, the supply of compressed air to the vacuum ejector 130 is stopped at the supply destination position to release (break) the vacuum. In this example, since it is held with a gap fit, the talc ring 8 can be dropped and supplied toward the work in process, but if necessary, it is pushed out by a pusher or both chuck claws 110. It may be supplied by opening the window. Simultaneously with this release, air may be sent into the slit 121 by a vacuum break circuit. After the supply, the chuck device 101 is returned to the original position (predetermined position as the supply source of the talc ring 8), the chuck claw 110 is opened, the process returns to the reception of the next talc ring 8, and the above-described steps are repeated. Control may be performed.

  On the other hand, when the predetermined vacuum degree is not obtained by the vacuum gauge 133 and it is determined as “failed product”, on the basis of the signal, for example, the supply of compressed air to the vacuum ejector 130 is stopped and both chucks are stopped. The nail | claw 110 may be opened, it may be dropped to the disposal container chute by another means (for example, pusher or air blow-off) at that position, and the above steps may be repeated after returning to receiving another talc ring 8. That is, by including such a pass / fail determination method, it is possible to easily prevent the rejected product from being supplied to the next process (the caulking process, see FIG. 9B). In this example, “failed product” includes empty supply (holding error). As a result, not only the pass / fail inspection at the supply destination (immediately before the caulking process) but also the inspection for the presence or absence of empty supply can be omitted, so that the inspection cost can be reduced and the inspection efficiency can be improved. Thus, according to the spark plug manufacturing method including the supply method of the talc ring 8 in the spark plug manufacturing and assembling process, a spark plug with high sealing performance can be obtained efficiently.

  In addition, in addition to the distinction and determination of acceptable products and unacceptable products, when the determination of empty supply (holding error) is separately distinguished and included, for example, the following may be performed. The “accepted product” has the same predetermined degree of vacuum as described above (for example, a degree of vacuum higher than −40 kPa), but it is determined that the “unacceptable product” is a predetermined reduced pressure (low degree of vacuum). For example, -29 kPa) is obtained, but when a predetermined vacuum degree as an acceptable product is not obtained, and when even this predetermined reduced pressure (low vacuum degree) is not obtained, it is determined as empty supply (holding error). That's it. In addition, since this holding | maintenance mistake is also judged from a vacuum degree (gauge pressure), this includes what has a big chip. As described above, when including a determination method of not only acceptance / rejection but also a holding error, appropriate countermeasures such as management are performed by stopping evacuation based on a holding error signal and visual confirmation by an operator. You can do that. In addition, when it is desired to distinguish the “failed product” into, for example, two stages of a serious defect (large chipped product) and a light defect (small chipped product), a predetermined pressure reduction (low vacuum degree. For example, −29 kPa). ) Is obtained as “lightly defective”, a case where only a lower degree of vacuum (for example, −15 kPa) can be obtained is designated as “seriously bad”, and a case where even this lower degree of vacuum cannot be obtained is empty supply (retained) (Miss) may be determined. That is, the control based on the subdivided determination settings may be appropriately performed according to the inspection level or the management level.

  Thus, in addition to the acceptance / rejection determination, it is possible to perform finer manufacturing management, such as by detecting an empty supply (holding error), such as a failure in loading the talc ring 8 to the chuck device 101. it can. In addition, the control for the subsequent rejected product processing when it is determined to be a rejected product (control including the journal according to the level of the rejected product) and the control after the determination of the holding error are appropriate. And it is sufficient.

  In this example, the left and right chuck claws 110 are the same, and the slits 121 are also arranged in the same manner and cut into the left and right closing surfaces (planes) 113. For this reason, when the left and right chuck claws 110 are closed, the space formed between the slit 121 in each of the left and right chuck claws 110 and the outer peripheral surface of the talc ring 8 communicates. Thereby, in this example, pass / fail determination can be performed by evacuating with the vacuum ejector 130 provided in one chuck nail | claw 110. FIG. Further, even when the single talc ring 8 is evacuated by both vacuum ejectors 130, the evacuation may be alternately performed.

  In the above example, the suction opening 119 provided on the chuck surface 115 forms slits 121 extending in the circumferential direction (lateral direction) at a predetermined interval above and below the chuck surface (semi-cylindrical surface). By providing as an opening at the end, the chuck surface 115 is provided so as to be distributed over the entire area facing the outer peripheral surface of the talc ring 8 to be adsorbed. A plurality of slits extending in a direction or in a spiral shape can be provided in parallel or the like at a predetermined interval. In any case, a region of the chuck surface (surface for holding vacuum) 115 having a predetermined width (vertical width) is left at a portion near the upper and lower ends of the chuck surface 115 so as to open in the chuck surface 115, and vacuum is applied. Try to prevent air inflow (reverse leak) during pulling.

  The suction opening 119 provided in the chuck surface 115 is not formed as a slit 121 penetrating to the back surface, but is provided as a concave groove recessed in the chuck surface 115, and these are communicated at appropriate positions so that the entire air in the concave groove (space) is sucked. You just have to be done. Further, the suction openings are not formed by the slits 121 or the concave grooves extending long on the chuck surface 115, but are distributed in a large number of holes (for example, circular holes and square holes) that are dispersed at an appropriate density in the entire region. It is good. These suction openings are preferably provided in a regular arrangement, but may be provided in an irregular arrangement. That is, the suction openings may be provided in a distributed manner in the entire area facing the outer peripheral surface of the cylindrical member such as the talc ring to be adsorbed on the chuck surface. Since it is not an acceptable product and there is a certain amount of chipping, cracking, or hole in any part of the cylindrical member, a predetermined degree of vacuum can be obtained by drawing air (inflow) from that in vacuuming. This is because it is only necessary to be able to determine that it is not possible.

  In the above example, the chuck surface 115 of the chuck device 101 is divided into two chuck claws 110 that enclose the cylindrical member by sandwiching the cylindrical member from both sides on the outer peripheral surface thereof, but it is divided into three (the end surface of the talc ring 8). In the case of 120 degrees) or more. However, if it is divided into two as described above, since the control to move the chuck claw 110 directly is sufficient, the opening / closing structure (drive mechanism) of the chuck device 101 is simplified. On the other hand, in the present invention, it is only necessary to surround the entire outer peripheral surface of the cylindrical member. Therefore, the shape and structure of the chuck surface 115 constituting the chuck device 101 having an integral cylindrical inner surface corresponding to the outer peripheral surface of the cylindrical member. As described above, it is also possible to use the above.

  In the above example, the vacuum ejector 130 is used as the vacuum generator. However, it goes without saying that a vacuum pump can also be used. In that case, for example, as shown in FIG. 8, for example, a filter or a vacuum gauge is provided in the middle of the piping from the screw hole 77 for the vacuuming piping toward the suction opening (suction port) of the vacuum pump 230. 133, a vacuum piping device that connects the evacuation start electromagnetic valve 236, the vacuum pressure adjustment valve 238, the stop valve 239, the vacuum tank 240, and the like may be used. In this case, the inside of the tank 240 may be maintained at a high vacuum level that is equal to or higher than a predetermined vacuum level, and evacuation may be performed by opening the evacuation start electromagnetic valve 236. The vacuum pump 230 may be selected from those having an appropriate degree of vacuum and exhaust speed according to the cylindrical member 8 and the supply work amount.

  The above is the case where the talc ring is supplied to the work in progress (before the caulking process) in the manufacturing and assembling of the spark plug. However, oxygen in the gas to be measured such as exhaust gas discharged from an internal combustion engine or the like has been described. In the production and assembly of the gas sensor for detecting the concentration, as shown in FIG. 11A, even when the talc ring 8 is supplied to the work in progress, it can be applied and embodied in the same manner, and the same effect can be obtained. can get. That is, according to the gas sensor manufacturing method including such a talc ring supply method in the gas sensor manufacturing and assembling process, a gas sensor with high sealing performance can be obtained efficiently. And in this invention, it is not restricted to such a talc ring, It can apply also to supply of another cylindrical member.

1 spark plug 8 talc ring (tubular member)
DESCRIPTION OF SYMBOLS 11 Gas sensor 101 Vacuum chuck apparatus 110 Chuck claw 115 Chuck surface 119 Suction opening 121 Slit

Claims (7)

By vacuuming at the suction opening that opens on the chuck surface of the vacuum chuck device, the outer peripheral surface of the cylindrical member is attracted to the chuck surface to hold the cylindrical member, and the suction is released at the supply position. In the method of supplying the tubular member by
The chuck surface of the vacuum chuck device used in the supply method surrounds the entire outer peripheral surface of the cylindrical member, and the entire outer periphery of the cylindrical member has a small gap fit or is not tightened. The suction openings are provided so as to be in close contact with the entire surface, and arranged so as to be distributed over the entire area of the chuck surface facing the outer peripheral surface of the cylindrical member to be adsorbed. A cylindrical member supply method characterized by the above. When adsorbing the cylindrical member to the chuck surface by vacuuming,
When the degree of vacuum obtained by the evacuation is higher than a predetermined degree of vacuum, it is determined as an acceptable product, and when the predetermined degree of vacuum is not obtained, it is determined as an unacceptable product. The method for supplying a cylindrical member according to claim 1, further comprising a determination method. When adsorbing the cylindrical member to the chuck surface by vacuuming,
When the degree of vacuum obtained by evacuation is higher than a predetermined degree of vacuum, it is determined as an acceptable product, and when a predetermined reduced pressure is obtained, but when the predetermined degree of vacuum is not obtained, it is determined as an unacceptable product. The cylindrical member supply according to claim 1, further comprising a cylindrical member pass / fail determination method and a holding error determination method for determining when the predetermined pressure reduction cannot be obtained as a holding error. Method.   The chuck surface is formed by being divided into two chuck claws provided in an opposing arrangement so as to surround the outer peripheral surface of the cylindrical member so as to be sandwiched from both radial sides. Item 4. The method for supplying a cylindrical member according to any one of Items 1 to 3.   The said cylindrical member is a talc ring, The supply method of the cylindrical member of any one of Claims 1-4 characterized by the above-mentioned.   A method for manufacturing a spark plug, comprising the method for supplying a cylindrical member according to claim 5 in a process for manufacturing and assembling a spark plug.   A method for manufacturing a gas sensor comprising the method for supplying a cylindrical member according to claim 5 in a manufacturing and assembling process of the gas sensor.

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