JP2005118851A - Metallic projection on metallic member and method for forming the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metallic projection for preventing link plates from falling off from the ends of the pins of a link chain constituted by longitudinally and transversely connecting the link plates by means of the pins inserted into their pin pores and a method for forming the projection. <P>SOLUTION: Metallic powder is sprinkled over the point to be formed with the projection 12 on the metallic member 10. The metallic powder is irradiated with a laser beam 20. The metallic projection is formed by the build-up of the molten metallic powder. At this time, the irradiation with the laser beam is intermittently performed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a metal protrusion formed on a metal member and a method for forming the metal protrusion.

It has been practiced for a long time to deposit molten metal on a metal member, but with the development of laser technology, metal powder has been applied to the location where the overlay on the metal member should be formed. It has been practiced to pour and irradiate a metal powder with a laser beam to melt the metal powder to form a built-up portion. Forming a metal overlay by laser heating of such metal powder is shown, for example, in the following Patent Documents 1 and 2 as a technique for forming a valve seat of an engine from a metal different from the valve body. On the other hand, in a link chain in which a plurality of link plates are connected vertically and horizontally by pins passed through the pin holes, resistance welding is applied to the ends of the pins in order to prevent the link plates from falling off the ends of the pins. Patent Document 3 below describes fixing the protrusions by friction welding or ultrasonic welding.
JP-A-3-41272 JP-A-5-5593 Japanese Patent Laid-Open No. 2001-300685

  As described in Patent Document 1 or 2, when the valve seat is formed of a built-up metal, the valve seat has a gentle chevron-shaped cross section, so that a metal powder is poured into a portion where the valve seat is to be formed. However, it is considered that there is no difficulty in forming a built-up portion having a desired cross-sectional shape by irradiating a laser beam there. However, a metal powder is poured into a protrusion with a relatively steep ridge, such as a protrusion for preventing a link plate from falling off in a link chain, which is intended as a main application of the present invention. However, if an attempt is made to irradiate with a laser beam, the molten metal lump will flow laterally before increasing its height, which is extremely difficult.

  On the other hand, as described in Patent Document 3, it is difficult to obtain strong fixation by a method of fixing a metal piece formed in a columnar shape on a metal member by resistance welding, friction welding, or ultrasonic welding. When the required projection height differs in two or more, as in the case of a link plate dropout prevention projection in the link chain, resistance welding and friction welding are performed according to the height of each projection. Or, there is the inconvenience that separate sizing is required for the apparatus for ultrasonic welding.

  The present invention addresses the above-described circumstances, pours metal powder onto a portion on which a protrusion is to be formed on a metal member, irradiates the metal powder with a laser beam, and forms a metal protrusion by a built-up body in which the metal powder is melted It is an object to form a protrusion with a steep bulge so that the side surface can act as a stopper.

  In order to solve the above-described problems, the present invention provides a projection formed by a built-up body in which metal powder is melted by laser beam irradiation on a metal member, and laser beam is intermittently irradiated to the metal powder. The metal powder is poured into a metal protrusion characterized by being formed on the metal member and the protrusion on the metal member where the protrusion is to be formed, and the metal powder is irradiated with a laser beam to melt the metal powder. The present invention proposes a method in which the metal powder is formed by the build-up body, and the laser beam irradiation is intermittently performed on the metal powder.

  The built-up body has a layered structure in which the lump portions melted by each irradiation in the intermittent irradiation of the laser beam are layered, and has a height corresponding to the number of the lump portions stacked. It's okay. In this case, the metal powder may be continuously poured into a portion where the build-up body is formed, and the metal powder is poured into the portion where the protrusion is to be formed in an annular shape from around the laser beam. The height of the build-up body may be determined according to the number of stacked layers.

  The protrusion is provided at the end of the pin to prevent the link plate from falling off the end of the pin in a link chain in which a plurality of link plates are connected vertically and horizontally by pins passed through the pin holes. It may be a protrusion provided.

  As described above, if the metal powder is intermittently irradiated with the laser beam when forming the protrusion formed by the built-up body in which the metal powder is melted by the laser beam irradiation on the metal member, the laser By appropriately adjusting the irradiation time for each intermittent irradiation of light, the amount of heat applied to the metal powder is appropriately set by each irradiation, and the molten state is obtained by each irradiation. The size of the metal lump can be set appropriately, and at the same time, the flow of the metal lump melted by each irradiation can be cooled by appropriately adjusting the length of the irradiation suspension time between intermittent irradiations. The shape of the metal lump obtained by the above can be set appropriately, and by selecting the irradiation time and rest time of each time, a plane cross section of a desired size can be obtained from the metal powder poured on the metal member. Having a columnar overlay It is possible to form the body.

  As described above, according to intermittent irradiation of the laser beam, a lump of metal is piled up for each irradiation and each subsequent pause, so that the formed body is melted by each irradiation Can be made into a layered structure laminated in layers, and the height thereof can be set to a height corresponding to the number of laminated metal blocks.

  Even if the laser beam is intermittently irradiated, the apparatus for pouring the metal powder may be simple because the metal powder may be continuously poured into the place where the body is formed. If the pouring of the metal powder to the portion where the protrusion is to be formed is performed in an annular shape from around the laser beam, it becomes easy to form the built-up body in a columnar shape.

  In a link chain in which a plurality of link plates are connected vertically and horizontally by pins passed through the pin holes, a protrusion is provided at the end of the pin to prevent the link plate from falling off the end of the pin. However, when such protrusions are formed by attaching metal pieces by resistance welding, friction welding, or ultrasonic welding, there are various inconveniences and difficulties. In this way, columnar protrusions suitable as a means for preventing the link plate from falling off are formed in a shape having high strength and no variation in the finished product, while arbitrarily changing the height. be able to.

  FIG. 1 attached herewith is a schematic view showing a state in which columnar protrusions 12 are being formed by melting and depositing metal powder at predetermined locations on a metal member 10 such as a link plate by the method of the present invention. 14 is a device in which a metal powder injection nozzle is incorporated in a laser beam irradiation head of a laser beam irradiation device made by a known laser technology, and is an illustration that is somewhat enlarged by expanding the arrow view 2-2. As shown in FIG. 2, an annular metal powder injection port 18 is provided around the laser beam emission port 16. A laser beam 20 converged so as to exhibit a substantially uniform circular cross section is emitted from the laser beam emission port 16, and a metal powder is tapered from the annular metal powder injection port 18 around the laser beam emission port 16. Are to be injected.

  Laser irradiation from the laser beam emission port 16 is intermittently performed as shown in the graph of FIG. In this case, the laser irradiation time and the pause time in the intermittent irradiation depend on the size of the projection to be formed, the number of the built-up layers, the specifications of the built-up material, the energy density of the laser beam, etc. May be set as appropriate.

  FIG. 4 is a partial side view showing an example of a link chain in which a link plate retaining projection is formed at an end of a pin in the manner described above. As shown in the drawing, the link chain has a plurality of link plates, which are oblong annular plates such as the link plate 24, which is the foremost in the drawing and is visible in its entirety, at both ends of the pin hole 26. By passing two pairs of pins 28 and 30 through a pair, it has a structure connected vertically and horizontally. At the end portions of the pins 28 and 30, link plate retaining projections 32 and 34 as shown in the figure are provided as described above with reference to FIGS. In this case, since the cross-sectional shape of the pin 28 and the shape of the pin hole 26 related thereto are different from the cross-sectional shape of the pin 30 and the shape of the pin hole 26 related thereto, the link chain is shown in the figure. When turning around a pulley not shown, the size of the gap formed between the pin and the inner edge of the pin hole of the link plate differs at the position where each of the protrusions 32 and 34 is provided. The heights of the protrusions required to reliably prevent the protrusions 32 and 34 are different from each other. In the illustrated example, the protrusion 34 is higher than the protrusion 32.

  However, even if the necessary heights of the protrusions 32 and 34 are different in this way, according to the present invention, the protrusions formed can be formed only by changing the number of times of intermittently irradiating the laser beam as described above. The height of can be easily changed.

  FIG. 5 is a partial cross-sectional view showing another example of an endless chain belt of a belt-type continuously variable transmission in which a link plate retaining projection is formed at the end of a pin by overlaying by laser beam intermittent irradiation as described above. FIG. 6 is a plan view, and FIG. 6 is a side view of a part of the chain belt shown in FIG.

  In these figures, 110a, 110b, 110c, 110d, 110e, 110f, 110g, 110h, 110i and the like are all link plates having the same shape, and are arranged side by side as shown in FIG. 2 pin holes 112ar, 112bf, 112br, 112cf, 112cr, 112df, 112dr, 112ef, etc. provided at both ends in the vertical direction (however, in the illustrated embodiment, two pin holes in each link plate, For example, the pin holes 112cf and 112cr of the link plate 110c are connected to each other vertically and horizontally by pins 114a, 114b, 114c, 114d and the like penetrating through both ends of one continuous long hole). Each of the pins 114a, 114b, 114c, 114d and the like is composed of a pair of arc-shaped pin halves 116af, 116ar, 116bf, 116br, 116cf, 116cr, 116df, 116dr, etc., and these pin halves Engage with the corresponding pin holes 112bf, 112ar, 112cf, 112br, 112df, 112cr, 112ef, 112dr, etc. at the outer surfaces 118af, 118ar, 118bf, 118br, 118cf, 118cr, 118df, 118dr, etc., whose surface contours are generally arcuate Thus, while being held in the pin hole, the cross-sectional contours of the respective inner surfaces 120af, 120ar, 120bf, 120br, 120cf, 120cr, 120df, 120dr and the like are in rolling engagement with each other. It has become.

  The pin halves 116af, 116ar to 116hf, 116hr, etc. are provided with link plate retaining projections 122afp, 122afq, 122arp at positions where they are close to the outermost link plate, respectively, at the portions receiving the outermost link plates at both ends. 122arq, 122bfp, 122bfq, 122brp, 122brq, 122cfp, 122cfq, 122crp, 122crq, 122dfp, 122dfq, 122drp, 122drq, 122efp, 122efq, 122erp, 122erq, 122ffp, 122ffq, 122frp, 122frq, 122gq, 122gq 122hfp, 122hfq, 122hrp, 122hrq and the like are provided in the above-described manner to prevent the link plate from falling off from each pin.

  In this case, in order to reduce the noise caused by the resonance effect caused by the pins periodically sitting on the pulley, the chain belt has the adjacent pins on the pulley even if the link plates are all of the same shape. The device has been devised to vary the effective pitch of sitting on the chair. That is, in the illustrated portion of the chain belt, one of the pair of pin halves is shortened by 114a, 114d, 114e, 114f, 114g, and 114h excluding the pins 114b and 114c, and the pins 114a and 114b are viewed. The two adjacent pin halves of the two adjacent pins are the shortened pin half 116ar and the non-shortened pin half 116bf, so that the pitch between the two adjacent pins is intermediate. The pitch Pmed. Further, regarding the pins 114b and 114c, the two pin halves facing each other of the two adjacent pins are the pin halves 116br and 116cf that are not shortened, so that the two adjacent pin halves The pitch between them is the minimum pitch Pmin. Looking at the pins 114c and 114d, the two pin halves of the two adjacent pins facing each other are the pin halves 116cr and 116df that are not shortened, and the pitch between the two adjacent pins is The minimum pitch Pmin.

  Further, regarding the pins 114e and 114f, the two pin halves facing each other of the two adjacent pins are the non-shortened pin half 116er and the shorted pin half 116ff, and the two adjacent pin halves The pitch between the pins is an intermediate pitch Pmed. Looking at the pins 114f and 114g, the two pin halves of the two adjacent pins facing each other are the pin halves 116fr and 116gf that are not shortened, and the pitch between the two adjacent pins is the minimum pitch. Pmin. As for the pins 114g and 114h, the two pin halves facing each other of the two adjacent pins are the pin halves 116gr and 116hf which are shortened, and at this time, between the two adjacent pins. Is the maximum pitch Pmax.

  Thus, even if the link plates are all of the same shape, one of the pair of pin halves is shorter than the other of at least some of the pins formed by the combination of the pair of pin halves and is generally formed in a conical shape. In the combination of a pair of pin halves of different lengths, only the longer pin halves are present when they are spanned between a pair of pulley halves not shown in the figure showing the belt engaging surface. By contacting the belt engaging surface at both ends, the contact pitch of the pin half with respect to the belt engaging surface can be changed among three types such as Pmin, Pmax and Pmed. If at least any two of them are irregularly arranged, resonance at the time of operation of the chain belt is avoided, and at least a chain belt without an increase in noise level due to resonance is obtained. When two types of pitches are used, they are relatively long and short, and can be irregularly arranged, for example, long, short, long, short, long and short.

  While the present invention has been described in detail with respect to several embodiments thereof, it will be apparent to those skilled in the art that various modifications can be made to these embodiments within the scope of the present invention. .

Schematic which shows the state which is forming the columnar processus | protrusion by the molten buildup of metal powder in the predetermined location on metal members like a link plate by the method of this invention. The figure which expands the arrow view by the arrow view surface 2-2 in FIG. The graph which shows the point that a laser irradiation is performed intermittently. The partial side view which shows an example of the link chain in which the protrusion for link plate removal prevention was formed in the edge part of a pin by this invention. The fragmentary top view by the partial cross section which shows another example of the link chain in which the protrusion for link plate prevention was formed in the edge part of a pin by this invention. FIG. 6 is a side view of a part of the chain belt shown in FIG. 5.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Metal member, 12 ... Protrusion, 14 ... Laser beam irradiation head, 16 ... Laser beam emission port, 18 ... Metal powder injection port, 20 ... Laser beam, 22 ... Tapered conical cylindrical flow of metal powder, 24 ... Link plate 26 ... pin hole, 28, 30 ... pin, 32, 34 ... link plate retaining projection, 110a-110i ... link, 112ar-112ef ... pin hole, 114a-114h ... pin, 116af-116hr ... half pin, 118af to 118dr ... outer side surface of pin half, 120af to 120dr ... inner side surface of pin half, 122afp to 122hrq ... projection for retaining link plate

Claims (7)

  The metal powder is formed on the metal member by forming a protrusion formed by a built-up body in which the metal powder is melted by laser beam irradiation, and the metal powder is intermittently irradiated with the laser beam. Metal protrusion.   The built-up body has a layered structure in which the lump portions melted by each irradiation in the intermittent irradiation of the laser beam are layered, and has a height corresponding to the number of the lump portions stacked. The metal protrusion according to claim 1, wherein the metal protrusion is provided.   The protrusion is provided at the end of the pin to prevent the link plate from falling off the end of the pin in a link chain in which a plurality of link plates are connected vertically and horizontally by pins passed through the pin holes. The metal protrusion according to claim 1, wherein the protrusion is a provided protrusion.   Metal powder is poured into a portion on the metal member where a protrusion is to be formed, the metal powder is irradiated with a laser beam, and a metal protrusion is formed by a built-up body in which the metal powder is melted. A method characterized in that the laser beam irradiation is performed intermittently.   The metal powder is continuously poured into a portion where the build-up body is formed, and the lump that is melted by each irradiation in the intermittent irradiation of the laser beam is laminated in layers, and the lump of the lump is laminated. The method according to claim 4, wherein the height of the body is determined by a number.   6. The method according to claim 4 or 5, wherein the pouring of the metal powder into a portion where the protrusion is to be formed is performed in an annular shape from around the laser beam. The protrusion is formed at the end of the pin in order to prevent the link plate from falling off from the end of the pin in a link chain in which a plurality of link plates are connected vertically and horizontally by pins passed through the pin holes. The method according to claim 4, wherein the method is provided.

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