JP5253145B2 - Method of manufacturing vacuum transfer device and vacuum transfer device - Google Patents

Description

  The present invention relates to a method for manufacturing a vacuum transfer device and a vacuum transfer device.

  In general, a manufacturing apparatus for manufacturing a semiconductor device or the like includes a transfer robot that transfers a substrate and the like between processing chambers and the like that perform predetermined processing in a vacuum. The transfer robot includes a support unit that supports a substrate and the like, and an arm that is connected to the support unit and that loads and unloads the substrate and the like using a motor as a drive source.

  Conventionally, as an arm of this transfer robot, an arm whose shape is formed by casting or an arm manufactured by cutting a metal block material has been widely employed. Although this arm has the advantage of high machining accuracy, there is a problem that the weight of the arm itself cannot be avoided and the load during driving becomes excessive. For this reason, the weight of the arm has been reduced by using a lightweight material such as an aluminum material.

  However, when the weight of the arm is reduced by changing the material, the material of the arm is greatly restricted. For example, when using a transfer robot in a harsh environment where the arm becomes hot, it is necessary to select a material with a low coefficient of linear expansion in order to suppress the expansion and contraction of the arm due to heat. It has been difficult to select a material that suitably satisfies conditions such as high, light weight, and low expansion rate. Even if the arm is made thinner for weight reduction, there is a limit in the cutting process.

On the other hand, an arm that reduces the weight by using a hollow pipe member has also been proposed (see, for example, Patent Document 1). This arm is formed by arc welding or the like of a pipe member and other parts. Such an arm has an advantage that the weight can be significantly reduced as compared with an arm obtained by cutting an aluminum material or the like. In addition, since the material is not limited in weight reduction, the degree of freedom of the material is improved.
JP-A-11-254374

  However, when the above-mentioned components constituting the arm are joined by welding, the base material itself is melted at a high temperature, so that distortion of the arm due to local temperature rise at the joint becomes a problem. When the distortion of the arm is large, the accuracy such as the inter-axis distance between the joint axes and the arm length is lowered, which may adversely affect the operation of the transfer robot. For this reason, in consideration of distortion caused by welding, the cutting margin (margin) is secured in advance for each part, and the position is adjusted after welding to maintain accuracy. In addition to securing the allowance in units of several millimeters, there is a problem in that the amount of cutting in the above processing increases, which takes time. In addition, when the amount of cutting after welding is large, it is necessary to use a cutting fluid that suppresses thermal expansion in the vicinity of the machining surface. However, if a cutting fluid is used, a cleaning process for removing the cutting fluid adhering to the part, etc. There is a problem that the number of steps increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for manufacturing a vacuum transfer apparatus and a vacuum transfer apparatus that can simplify the manufacturing process while reducing the weight of the arm. There is.

In order to solve the above-described problems, the invention according to claim 1 is a method of manufacturing a vacuum transfer device including an arm, wherein the arm member is formed of a plurality of arm members made of a metal plate and the same kind of material as the metal plate. and a joint member formed, forming a deaerating hole in said arm member, said arm member and to adhere the brazing material against the joint between the joint member, the deaerating hole and communicating with the air gap on the inside A step of assembling the arm having a hollow structure, heating the assembled arm in vacuum, and setting the heating temperature to a melting temperature of the brazing material as a target temperature, and between a thick portion and a thin portion of the brazing material A step of brazing the joint by increasing the temperature rising rate while maintaining a temperature difference that does not become excessive; and a temperature difference between the members after the heating temperature reaches the target temperature and the brazing material is melted Is excessive And summarized in that a step of solidifying the brazing material is heat radiation while maintaining a temperature decrease rate that do not.

According to this method, the plurality of arm members constituting the arm are joined by brazing. Therefore, it is possible to suppress the occurrence of a large distortion by the step of joining the constituent members while reducing the weight of the arm by adopting a hollow structure. Therefore, it is possible to reduce the load and the number of steps in the processing after joining for the purpose of adjusting the member position and the like. According to this method, the arm member and the joint member are formed of the same kind of material. Accordingly, even when the entire arm is heated during brazing, the temperature difference generated in each member can be suppressed, so that local thermal expansion can be suppressed and the occurrence of distortion can be suppressed. Further, according to this method, since the entire arm can be gradually heated and dissipated by brazing the joint, occurrence of distortion due to a rapid temperature difference can be suppressed. Furthermore, in the brazing step, the entire arm can be heat-treated, so that it can also serve as a step of discharging and removing impurities adhering to each member from the deaeration holes. For this reason, the effect that a cleaning process, surface treatment, etc. required in other manufacturing processes can be omitted can be obtained.

According to a second aspect of the present invention, in the method for manufacturing a vacuum transfer device according to the first aspect , the metal plate to which the nickel plating is applied and the joint portion of the joint member are brazing materials mainly composed of nickel. The gist is to join together.

According to this method, the joint portion of the metal plate and the joint member to which the nickel plating is applied is joined by the brazing material mainly composed of nickel. That is, by using a brazing material having high wettability with respect to the metal plate and the joint member , the brazing material can be widely flowed in the joint portion, and the joint portion can be firmly fixed.

According to a third aspect of the present invention, in the method for manufacturing a vacuum transfer device according to the first aspect , the metal plate made of stainless steel and the joint portion of the joint member are joined by a brazing material mainly composed of nickel. The gist is to do.

According to this method, the metal plate and the joint member are made of stainless steel, and the joint portion is joined by the brazing material mainly composed of nickel. That is, by using a brazing material having high wettability with respect to the metal plate and the joint member , the brazing material can be widely flowed in the joint portion, and the joint portion can be firmly fixed.

Invention of claim 4, the arm body including a plurality of metal plates, possess a joint member for supporting the joint shaft, an arm having a hollow structure to have a void on the inside, at least a portion A deaeration hole communicating with the gap of the arm is formed in the metal plate, and a joint portion for joining the metal plates to each other, and a joint portion of the metal plate and the joint member are joined by a brazing material. Is the gist.

According to this configuration, the vacuum transfer device includes an arm having a hollow structure having an arm main body formed of a plurality of metal plates and a joint member that supports the joint shaft. Moreover, the junction part of each of those members is joined by the brazing material. Therefore, by using a hollow structure, the arm is reduced in weight, and the member is not locally heated as in the joining by welding, so that the accuracy such as the inter-axis distance of the arm can be improved. Therefore, it is possible to manufacture a highly accurate arm while reducing the load and the number of processes in the processing after brazing. Further, in the brazing process, since the entire arm can be heat-treated, it can also serve as a process of discharging and removing impurities adhering to each member from the deaeration holes. For this reason, the effect that a cleaning process, surface treatment, etc. required in other manufacturing processes can be omitted can be obtained.

The invention of claim 5 is the vacuum transfer apparatus of claim 4, the first wall portion constituting the arm, the junction between the second wall portion that is joined to the first wall portion The gist is that a step is formed between the first wall portion and the second wall portion to be reinforced with a brazing material.

  According to this structure, the level | step difference for reinforcing between the 1st wall part and the 2nd wall part with a brazing material is provided in the junction part of the 1st wall part and 2nd wall part of an arm. . Therefore, since the joint can be reinforced by the brazing material by providing the step, each wall can be firmly fixed.

  As described above, according to the present invention, it is possible to provide a method of manufacturing a vacuum transfer device and a vacuum transfer device that can improve the accuracy of a hollow arm.

  Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. FIG. 1 shows an example of a transfer robot 1 that embodies the vacuum transfer apparatus of the present invention. The transfer robot 1 transfers the substrate before and after processing to a predetermined position between the processing chambers and the like that process the substrate under vacuum. The transfer robot 1 includes a mount flange 2 formed in a cylindrical shape, and this is fixed to a vacuum transfer chamber. Two first arms 5 are connected to the upper surface 2 </ b> A of the mount flange 2 via a turning block 3. Between each first arm 5, each plate-like link member 7 is fixed between one end where the first joint shaft 6 is provided and the other end located on the opposite side to the one end. Yes. Each link member 7 has one end connected to each first arm 5 by a pin 7A as a joint axis, and the other end connected to each second arm 8 adjacent to the first arm 5 by a pin 7A. . Similar to the first arm 5, the second arm 8 has a hollow structure and is formed in the same shape as the first arm 5. Further, one end of the second arm 8 is pivotally supported on each second joint shaft 9 as a joint shaft rotatably supported on the mount flange 2 via the turning block 3, and the first arm 5 is rotated. Following the movement, it rotates in parallel with the first arm 5. In addition, the height position of one first arm 5 on the left side in the drawing is located above the height position of the other first arm 5 on the right side in the drawing, and the second arm 8 on the left side in the drawing. Is connected to the first arm 5 pivotally supported at a relatively high position, and is arranged at a position higher than the height position of the second arm 8 on the right side in the drawing.

  A plurality of concentric shafts are provided inside the mount flange 2, and these concentric shafts are driven by a motor in the mount flange 2 constrained in the rotational direction by the mount flange 2, each of which is a predetermined source. It can be rotated in the direction. Then, the turning block 3 that holds the first joint shaft 6 is driven to turn by one of the plurality of concentric shafts. Further, two of the plurality of concentric shafts are connected to the first joint shaft 6 of the first arm 5 on the left side in the drawing and the first joint shaft 6 of the first arm 5 on the right side in the drawing, respectively. The first joint shaft 6 of the left first arm 5 in the drawing is driven by the concentric shaft connected to the first joint shaft 6 of the left first arm 5 in the drawing. Further, the first joint shaft 6 of the first arm 5 on the right side in the drawing is driven by the concentric shaft connected to the first joint shaft 6 of the first arm 5 on the right side in the drawing. That is, the first joint shaft 6 of the first arm 5 on the left side in the drawing and the first joint shaft 6 of the first arm 5 on the right side in the drawing can be driven independently. Note that the second joint shaft 9 of each second arm 8 can also be driven independently in the same manner as each first joint shaft 6.

Moreover, the base shaft 13b connected with the middle of the longitudinal direction of the 3rd arm 13 at the other end located in the opposite side with respect to the end in which each 1st joint shaft 6 was provided among each 1st arm 5 is respectively. It is pivotally supported. At one end in the longitudinal direction of each third arm 13, a guide shaft 10 extending downward is supported so as to be slidable along the guide groove 12 </ b> A of each support portion 12 fixed to the mounting plate 11. . These third arms 13 have a hollow structure and are formed in substantially the same shape as the first arm 5. Each third arm 13 operates in accordance with the rotation operation of the corresponding first arm 5 in such a manner that one end in the longitudinal direction is guided to the guide groove 12A via the guide shaft 10.

  In addition, a base shaft 16b connected to the middle of the fourth arm 16 in the longitudinal direction is provided at the other end of each second arm 8 on the opposite side to the one end where the second joint shaft 9 is provided. It is pivotally supported. A guide shaft 15 extending downward is supported at one end in the longitudinal direction of each fourth arm 16 so as to be slidable along the guide groove 14A of each support portion 14 fixed to the mounting plate 11. . These fourth arms 16 have a hollow structure and are formed in the same shape as the third arm 13. Each fourth arm 16 operates in accordance with the rotation operation of the corresponding second arm 8 in such a manner that one end in the longitudinal direction is guided to the guide groove 14A via the guide shaft 15.

  The substantially T-shaped link members 18 are supported by pins 17 at the tips of the third arm 13 and the fourth arm 16, respectively. As a result, the fourth arm 16 follows the rotation of the third arm 13 and rotates in parallel with the third arm 13.

A pair of connecting arms 19 </ b> A are fixed to the side ends of the link members 18. The connecting arm 19A places a substrate to be transported.
Further, since the height positions of the third arm 13 and the fourth arm 16 on the left side in the figure are the height positions of the arms 5 and 8 connected to the arms 13 and 16, the third arm on the right side in the figure. The position is higher than the height positions of 13 and the fourth arm 16. Accordingly, the connecting arm 19A connected to the left arms 13 and 16 in the drawing is located above the connecting arm 19A connected to the right arms 13 and 16 in the height direction. For this reason, for example, even when two substrates are transported, the height positions of the substrates supported by each connecting arm 19 are different, so that even if each arm expands or contracts or rotates, the substrate is not collided. it can. In addition, in order for each of the arms 5, 8, 13, and 16 to smoothly perform a predetermined operation such as expansion and contraction and rotation, the accuracy of the arm length, the distance between the axes of each rotation shaft, and the like is ensured. Is the premise.

  Next, the configuration of the first arm 5 and the manufacturing method thereof will be described in detail. The second arm 8 has the same configuration as the first arm 5, and the third arm 13 and the fourth arm 16 have the same configuration as the first arm 5 except for the position of their proximal ends, and each arm 8 , 13 and 16 are manufactured by the same method as the first arm 5, and the description of their configuration and manufacturing method is omitted.

  As shown in FIG. 2, the 1st arm 5 is provided with the ellipse-shaped arm main body 20 and each bush 21-23 as a joint member. The first bush 21 pivotally supports the first joint shaft 6, and the second bush 22 penetrates the pin 7 </ b> A of the link member 7. Further, the third bush 23 supports the guide shaft 10.

  As shown in FIG. 3, the arm body 20 includes an upper plate 25 serving as an arm member and a second wall portion, a lower plate 26, and an annular member 27 fixed between the upper plate 25 and the lower plate 26. ing. The upper plate 25 is formed of a sheet metal having a thickness of several millimeters (for example, 1 to 5 mm). The upper plate 25 has an elliptical shape, and a through hole 28 through which the first bush 21 is inserted is formed at one end thereof. Further, a through hole 30 for penetrating the third bush 23 is formed through one end where the through hole 28 is formed and the other end located on the opposite side. Further, a through-hole 29 for penetrating the pin 7A is formed in a position between the through-holes 28.30 and deviated toward the through-hole 30 side.

The lower plate 26 is formed in the same shape and the same size as the upper plate 25, and through holes 31 to 33 are formed in the same position as the upper plate 25.
The annular member 27 is formed in an annular shape by temporarily fastening the side ends of the plate-like members 27E to 27H formed in a band shape having a constant height H. In the present embodiment, each of the plate-like members 27E to 27H is formed of a sheet metal having a thickness of several millimeters (for example, 1 to 5 mm), and has two plate-like plate-like members 27E and 27F and a curved 2 A long oval shape is formed by welding and joining the two plate-like members 27G and 27H.

  The elliptical shape formed by the peripheral wall portion 27 </ b> C of the annular member 27 is formed to be slightly smaller than the elliptical shape that is the outer shape of the upper plate 25 and the lower plate 26. Therefore, when the peripheral wall portion 27C (first wall portion) of the annular member 27 is joined perpendicularly to the upper plate 25 and the lower plate 26 (second wall portion), the upper plate 25 and the lower plate 26 The outer peripheral surface (surface in the thickness direction) and the outer surface of the annular member 27 are not flush with each other, and a step is provided over the entire periphery of the joint. The plate-like members 27G and 27H are formed with deaeration holes 37 and 38 for exhausting gas, impurities and the like inside the arm.

  Moreover, the above-mentioned first bush 21 has an insertion hole 21 </ b> C made of a sliding surface for supporting the first joint shaft 6 on the inner side, and has flanges 21 </ b> A and 21 </ b> B at the upper end and the lower end, respectively. At the end of the flange 21A in the central axis direction, a step portion 21As extending in the central axis direction is provided over the entire circumference of the through hole 21C. The second bush 22 has a through hole 22C through which the above-described pin 7A is inserted, and has flanges 22A and 22B at the upper and lower ends thereof. At the end portions of the flanges 22A and 22B in the central axis direction, step portions 22As and step portions 22Bs extending in the respective central axis directions are provided over the entire circumference of the through hole 22C. Furthermore, the 3rd bush 23 has the penetration hole 23C which consists of a sliding surface for supporting the guide shaft 10 inside, and has flange 23A, 23B at the upper end and lower end, respectively. At the end portions of the flanges 23A and 23B in the central axis direction, step portions 23As and step portions 23Bs are provided over the entire circumference of the through hole 23C, respectively.

  The upper plate 25, the lower plate 26, the annular member 27, and the bushes 21 to 23 each have a minute gap in a joint portion for joining each other, and brazing (brazing) in which a brazing material is poured into the gap. Joined by. In brazing, a brazing material having a melting point lower than that of the base material is attached to these joints, and the entire first arm is heated to a temperature at which the brazing material is melted in a state of being assembled into the shape of the first arm 5. Then, after the molten brazing material flows in the gaps between the members, heat is released and the brazing material is solidified.

  When the upper plate 25, the lower plate 26, the annular member 27, and the bushes 21 to 23 are joined by brazing in this way, they can be joined at a temperature lower than the melting point of those materials. Rather than melting and joining the base materials themselves, thermal expansion of each member can be suppressed. In particular, when the arm 5 is formed from the upper plate 25, the lower plate 26 and the annular member 27 using a thin sheet metal to reduce the weight of the arm as in the present embodiment, the distortion increases when the arm 5 is joined by welding. Therefore, distortion of the base material can be suppressed by joining the base material with the brazing material without melting the base material. In addition, by using a shell-like structure in which the annular member 27 is fixed between the upper plate 25 and the lower plate 26, a monocoque structure with improved strength against torsion and the like applied during the conveying operation can be obtained.

  The upper plate 25, the lower plate 26, and the annular member 27 are made of the same kind of material. As this material, a material having a relatively small linear expansion coefficient is selected so that the first arm 5 is not adversely affected by thermal expansion even when a high temperature (about 500 ° C.) substrate is supported. As such a material, for example, permalloy steel, invar steel or the like can be suitably used. These materials have a relatively small coefficient of linear expansion, have rigidity required for the arm of the transfer robot 1, and can be plated with nickel to improve wettability with a brazing material to be described later. Moreover, a stainless steel material and a general steel material can also be used suitably. These materials have a relatively small coefficient of linear expansion, excellent rigidity, and excellent wettability with the brazing material.

As the brazing material used for brazing, a brazing material whose main component is nickel can be preferably used. Since the nickel-based brazing material has a relatively low melting point, it is possible to set the heating temperature at the time of brazing relatively low, and the upper plate 25, the lower plate 26, the annular member 27, and the bushes 21 to 21 can be set. The thermal expansion of 23 can be suppressed. In addition, it has the advantages of high heat resistance and corrosion resistance, is resistant to rusting, and is excellent in wettability with the material used for the first arm 5.

  The bushes 21 to 23 are made of the same material as the materials of the upper plate 25, the lower plate 26 and the annular member 27. That is, the composition of the materials of the bushes 21 to 23 may be almost the same as the composition of the materials of the upper plate 25, the lower plate 26 and the annular member 27. For example, when the upper plate 25 or the like is made of stainless steel, the bushes 21 to 23 are preferably formed of stainless steel. When the upper plate 25 or the like is made of permalloy steel or invar steel, the bushes 21 to 23 are formed. Are preferably formed from permalloy steel or invar steel, respectively.

  FIG. 4 shows a cross section of the first arm 5 joined by brazing. The brazed first arm 5 is formed in a hollow shape having a gap 40 on the inner side, and the weight of the arm is reduced. In FIGS. 3 and 4, for convenience, the thicknesses of the upper plate 25, the lower plate 26 and the annular member 27 are changed, but in actuality, they are made of thinner metal plates.

  Also, a brazing material is interposed in the gap between the lower surface 25B of the upper plate 25 and the upper end 27A of the annular member 27, and the gap between the upper surface 26A of the lower plate 26 and the lower end 27B of the annular member 27, and these members Are joined. Furthermore, the brazing material is also interposed in the gaps between the upper plate 25 and the lower plate 26 and the flanges 21A to 23A and 21B to 23B of the bushes 21 to 23.

  Further, as described above, since the elliptical shape formed by the upper end 27A and the lower end 27B of the annular member 27 is smaller than the outer shape of the upper plate 25 and the lower plate 26, as shown in the enlarged view on the left side in the drawing, the upper plate 25 A step 35 is formed at the joint between the ring member 27 and the annular member 27. The step 35 at the joint is provided so as to surround the upper end of the annular member 27.

  The step 35 easily forms a so-called fillet 33 that reinforces the lower surface 25B of the upper plate 25 and the outer surface 27D of the annular member 27 by the brazing material 32 protruding from between the upper plate 25 and the annular member 27. It is provided for. The fillet 33 has a curved surface (meniscus) formed by the surface tension of the brazing material 32 and is formed so as to fill the step 35. By forming the fillet 33 over the entire joining portion, not only the joining surface formed by the lower surface of the upper plate 25 and the upper end 27A of the annular member 27 is joined by the brazing material 32, but also outside the joining surface. Therefore, the upper plate 25 and the annular member 27 can be firmly fixed.

  A step 36 is also formed on the upper surface 26 </ b> A of the lower plate 26 and the lower end 27 </ b> B of the annular member 27. A fillet is formed on the step 36 by a brazing material that joins the lower plate 26 and the annular member 27.

  Further, a step is provided between each of the flanges 21 A and 21 B of the first bush 21, the flanges 22 A and 22 B of the second bush 22 and the flanges 23 A and 23 B of the third bush 23, and the arm body 20. As shown in the enlarged view on the right side of the figure, for example, the brazing material 32 poured into the gap between the flange 22 </ b> A of the second bush 22 and the upper plate 25 forms a fillet 33 at the step 34. Thereby, each said member can be fixed firmly.

Next, a method for manufacturing the first arm 5 will be described. First, the sheet metal of the above-described material is cut to form the upper plate 25, the lower plate 26, and plate members 27E to 27H constituting the annular member 27 (material removal). Further, each bushing 21 to 23 has a cutting allowance after brazing in units of 1/100 mm to 1/10 mm as necessary. Such a cutting allowance is required only when the positional accuracy of the bushes 21 to 23 after brazing does not satisfy the design requirements (when secondary processing is required). Usually, the fitting gap between each bushing 21 to 23 and the corresponding through hole is guaranteed in units of 1/100 mm. For this reason, the positional accuracy of the bushes 21 to 23 described above mainly depends on the assembly accuracy. Therefore, if such assembly accuracy is ensured by an assembly jig or the like, naturally, the above-described cutting allowance is unnecessary. It becomes.

  Next, processing such as forming a through hole is performed on the sheet metal formed in a predetermined shape to form the upper plate 25, the lower plate 26, and the annular member 27 (primary processing). At this time, the through holes 28 to 33 are formed in the upper plate 25 and the lower plate 26, respectively, and the deaeration holes 37 and 38 are formed in the plate members 27G and 27H. Further, the plate-like members 27G and 27H are formed in a curved shape, and the joint portions of the plate-like members 27E to 27H constituting the annular member 27 are welded. In addition, when using permalloy steel, Invar steel, etc., you may give a plating after welding.

  Further, the upper plate 25, the lower plate 26, the annular member 27, and the bushes 21 to 23 are assembled into the shape of the first arm 5 (assembly process). In this case, the step portion 23As provided on the flange 23A of the bush 23 is inserted from the inside of the annular member 27 into the through hole 30 of the upper plate 25, and a part thereof is exposed to the outside of the arm. Then, the end portion of the flange 23 </ b> A that protrudes outward in the radial direction from the stepped portion 23 </ b> As is disposed inside the arm so as to come into contact with the upper plate 25. Similarly, the step portion 23Bs provided on the flange 23B is inserted from the inside of the annular member 27 into the through hole 33h of the lower plate, and a part thereof is exposed to the outside of the arm. Then, the end of the flange 23 </ b> B protruding outward in the radial direction from the stepped portion 23 </ b> Bs is arranged on the inner side of the arm so as to come into contact with the lower plate 26. The upper plate 25, the lower plate 26, and the bush 23 are assembled by such a method. Incidentally, the assembly process of the bushing 22 is simultaneously performed in the same manner.

  On the other hand, the bush 21 is first inserted from the lower side of the through hole 31 of the lower plate 26. Thereby, the lower flange 21 </ b> B of the bush 21 and the bottom surface of the lower plate 26 come into contact with each other. Next, the step portion 21As provided on the flange 21A of the bush 21 is inserted from the inside of the annular member 27 into the through hole 28 of the upper plate 25, and a part thereof is exposed to the outside of the arm. Then, the end portion of the flange 21 </ b> A protruding outward in the radial direction from the stepped portion 21 </ b> As is disposed inside the arm so as to come into contact with the upper plate 25. By such a method, the assembly of the bush 21 is performed simultaneously with the assembly process of the bush 22 and the bush 23.

  At this time, a paste-like brazing material is applied to the gaps between the members. The brazing material may be applied after assembly, or may be applied in parallel with the assembly. In addition, when assembling, if the upper plate 25, the lower plate 26, the annular member 27, and the bushes 21 to 23 are temporarily fixed by spot welding, the positional accuracy of each member is improved. It is also possible to omit the next process itself.

  When the first arm 5 is assembled and the brazing material is attached to the joint, it is brazed by heating in a vacuum heating furnace (brazing process). At this time, the melting temperature (about 1000 ° C.) of the nickel-based brazing material is set as a target temperature, and heating is performed gradually while maintaining a temperature increase rate so that the temperature difference between the thick part and the thin part is not excessive ( For example, 100 ° C./hour). In the case of welding, the joint is heated to a high temperature at once. However, since the entire arm can be gradually heated by brazing, the occurrence of distortion due to a rapid temperature difference can be suppressed. Further, when the brazing material is melted by heating to the target temperature, the brazing material is solidified by gradually radiating heat at a temperature decreasing rate so that the temperature difference between the members does not become excessive.

  Moreover, in this brazing process, since the entire arm can be heat-treated, it can also serve as a process for removing impurities adhering to each member. For this reason, the effect that a cleaning process, surface treatment, etc. required in other manufacturing processes can be omitted can be obtained.

  Subsequently, in order to ensure the accuracy such as the distance between the axes of the bushes 21 to 23, machining such as cutting is performed (secondary processing). As described above, this step can be omitted when the secondary processing is unnecessary, such as when the position accuracy of the bushes 21 to 23 satisfies the design accuracy. By the way, in this secondary machining, the machining allowance secured in advance is cut and machining in units of 1/100 mm to 1/10 mm is performed, so that there is almost no thermal expansion of each member in the machining, and the machining surface is cooled. There is no need to use a cleaning solution. Therefore, the process for removing the cleaning liquid can be omitted.

  On the other hand, when joining by welding, since a joining part is heated locally (in the case of stainless steel, about 1400 degreeC), shift | offset | differences, such as a center distance, arise in a millimeter unit. For this reason, time is required for the secondary processing, and it is impossible to omit the secondary processing itself. Moreover, since the cutting amount after welding increases, it is necessary to use the above-described cleaning liquid in order to suppress the thermal expansion of the member in the secondary processing. When the cleaning liquid is used, a cleaning process, a surface treatment, etc. for removing the cleaning liquid are required, and the number of processes increases. In the manufacturing process using brazing, since these processes can be omitted as described above, the number of processes can be reduced compared to the manufacturing process using welding. Moreover, when joining each member by welding, only the part heated at high temperature is welded, and it has the fault that a clearance gap tends to remain in a junction part, and a bead (welding trace) remains, but in brazing, a brazing material is in a clearance gap. It is possible to improve the strength by spreading the material, and there is an advantage that a bead is not formed.

According to the above embodiment, the following effects can be obtained.
(1) In the above embodiment, when the arms 5, 8, 13, 16 of the transfer robot 1 are manufactured, the plurality of upper plates 25, the lower plate 26, the annular member 27, and the bushes constituting the arm body 20 are provided. The hollow arms 5, 8, 13, and 16 were assembled from 21 to 23, and the brazing material was adhered to the joints that joined the members together. Also, the assembled arms were heated by vacuuming and joined by brazing. Accordingly, the weight of each arm 5, 8, 13, 16 is reduced by making it hollow, and the members are not locally heated as in the case of joining by welding, so the distance between the axes of the arms 5, 8, 13, 16 and the like. Accuracy can be improved. Therefore, it is possible to reduce the load and the number of steps of secondary processing after joining for the purpose of adjusting the distance between the axes. In addition, since there is little variation in the distance between the axes after joining, the accuracy of each arm 5, 8, 13, 16 can be improved.

  (2) In the said embodiment, the upper side board 25, the lower side board 26, the cyclic | annular member 27, and each bush 21-23 were formed from the same kind of material. Therefore, even if the entire arm incorporating the bushes 21 to 23 is heated at the time of brazing, the temperature difference between the arm main body 20 and the bushes 21 to 23 does not become excessive, thereby suppressing local thermal expansion. , Can prevent the occurrence of distortion.

  (3) In the above embodiment, each member constituting the arm main body 20 is made of a material having high wettability with a general steel material, permalloy steel, Invar steel, stainless steel, or nickel-based brazing material to which nickel plating is applied. Formed from. For this reason, a joined part can be firmly fixed without a gap.

(4) In the above embodiment, the joint portion of the annular member 27 joined to the upper plate 25 and the lower plate 26, and the joint portion of the annular member 27 joined to the lower plate 26 and the lower plate 26 are included. A step for reinforcing the connection of the members is formed by the brazing material protruding from the members. Further, the bushes 21 to 23 and the upper plate 25 and the lower plate 26 are provided with steps. For this reason, reinforcement with a brazing material can be easily performed by providing these steps. Accordingly, the brazing material not only joins the joining surfaces of the respective members but also joins the outside thereof, so that the lower surface and the upper surface of the upper plate 25 and the lower plate 26 and the outer surface 27D of the annular member 27 are flush with each other. Each member can be fixed firmly rather than joining so that it may become. Further, the bushes 21 to 23 and the upper plate 25 and the lower plate 26 can be firmly fixed, and the accuracy of the inter-axis distance can be improved.

In addition, you may change the said embodiment as follows.
In the above embodiment, a nickel-based brazing material is used, but other brazing materials such as a brazing material mainly composed of silver may be used. Alternatively, solder having a melting temperature (melting point) lower than that of the nickel-based brazing material may be used.

  In the above embodiment, each member constituting the rod-like arms 5, 8, 13, 16 is manufactured by brazing, but the other part of the arm mechanism is formed in a hollow shape, and the constituent members constituting the part are formed. You may join by brazing. For example, a grip portion (not shown) that supports the substrate may be formed in a hollow shape, and each member constituting the grip portion may be formed by brazing.

  In the above embodiment, each component constituting the arm is formed from a metal material, but may be changed according to the condition to which the transfer robot 1 is applied. For example, when used in a relatively low temperature process, it may be formed from a resin plate.

  In the above embodiment, the transfer device of the present invention is embodied in the transfer robot 1 having a link mechanism in which two arms are connected by a link member. However, the present invention is not limited to this configuration, and transfer robots of other configurations are used. It may be embodied in.

The perspective view of the conveyance robot of this embodiment. The perspective view of an arm. The exploded perspective view of an arm. The longitudinal cross-sectional view of an arm.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Transfer robot as a vacuum transfer apparatus, 5 ... 1st arm, 6 ... 1st joint axis as a joint axis, 7A ... Pin as a joint axis, 8 ... 2nd arm, 9 ... 2nd joint as a joint axis Axis, 10 ... guide shaft as joint axis, 13 ... third arm, 15 ... guide shaft as joint axis, 16 ... fourth arm, 20 ... arm body, 21-23 ... bush as joint member, 25 ... arm Upper plate as member and second wall, 26 ... Lower plate as arm member and second wall, 27 ... Annular member as arm member and first wall, 27E to 27H ... Plate-like member as arm member 32 ... brazing material, 33 ... fillet constituting the joint, 34-36 ... step.

Claims (5)

In the manufacturing method of the vacuum transfer device provided with the arm,
Forming a plurality of arm members made of a metal plate and a joint member made of the same kind of material as the metal plate, and forming deaeration holes in the arm member;
A step of assembling the arms of hollow structure having voids which adhere the brazing material against the joint communicated with the deaerating hole inside of the joint member and the arm member,
The assembled arm is heated in vacuum , and the heating temperature is set to the melting temperature of the brazing material, and the temperature rise rate is maintained so that the temperature difference between the thick part and the thin part of the brazing material is not excessive. Raising the joint while brazing the joint ,
After the heating temperature reaches the target temperature and the brazing material is melted, it has a step of solidifying the brazing material by radiating heat while maintaining a temperature-decreasing rate at which the temperature difference between the members does not become excessive. A method for manufacturing a vacuum transfer device. In the manufacturing method of the vacuum conveyance device according to claim 1 ,
The joint portion of the metal plate and the joint member nickel plating is applied, the manufacturing method of the vacuum transfer apparatus that be joined by a brazing material composed mainly of nickel. In the manufacturing method of the vacuum conveyance device according to claim 1 ,
The joint portion of the metal plate and the joint member made of a stainless steel material, a manufacturing method of the vacuum transfer apparatus that be joined by a brazing material composed mainly of nickel. Includes an arm body including a plurality of metal plates, possess a joint member for supporting the joint shaft, the arm having a hollow structure to have a void on the inside,
At least a part of the metal plate is formed with a deaeration hole communicating with the gap of the arm,
A vacuum transfer device, wherein a joining portion for joining the metal plates to each other and a joining portion of the metal plate and the joint member are joined by a brazing material. In the vacuum conveyance apparatus of Claim 4 ,
A joint portion between the first wall portion constituting the arm and the second wall portion joined to the first wall portion has a space between the first wall portion and the second wall portion. A vacuum transfer device, characterized in that a step for crosslinking with a material is formed.

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