Patent ID: 12202079

DETAILED DESCRIPTION

Some embodiments of the present invention will be described below with reference to the accompanying drawings. It is intended, however, that unless particularly identified, dimensions, materials, shapes, relative positions and the like of components described or shown in the drawings as the embodiments shall be interpreted as illustrative only and not intended to limit the scope of the present invention.For instance, an expression of relative or absolute arrangement such as “in a direction”, “along a direction”, “parallel”, “orthogonal”, “centered”, “concentric” and “coaxial” shall not be construed as indicating only the arrangement in a strict literal sense, but also includes a state where the arrangement is relatively displaced by a tolerance, or by an angle or a distance whereby it is possible to achieve the same function.Further, for instance, an expression of a shape such as a rectangular shape or a cylindrical shape shall not be construed as only the geometrically strict shape, but also includes a shape with unevenness or chamfered corners within the range in which the same effect can be achieved.On the other hand, an expression such as “comprise”, “include”, “have”, “contain” and “constitute” are not intended to be exclusive of other components.

FIG.1shows a welding process of a plate laminated body using a welding device10according to an embodiment.FIG.2is a side view of the welding device10. As shown inFIG.1, a chuck12grips a plate laminated body102, plates100, and the like to be welded from both sides with a lamination direction being in a horizontal position (an axis direction of the plate laminated body102). At least one support14extends along the lamination direction and supports, from below, the plate laminated body102and the like gripped by the chuck12. A welding torch16is disposed on the radially outer side of the plate laminated body102supported by the support14. In the embodiment shown inFIG.1, a process is shown in which the plurality of plates100that constitute the plate laminated body102supported by the support14have already been welded at outer peripheral edges of the adjacent plates100, an outer peripheral edge of the plate100(100a) in the axial end portion of the plate laminated body102and an outer peripheral edge of the plate100(100b) newly introduced into the welding device10are welded.

The plate laminated body102and the plate100(100b) are gripped with a lamination direction being in a horizontal position by the chuck12, and are supported from below by the support14. In this state, the plate100(100a) and the plate100(100b) are disposed in a positional relationship where the outer peripheral edges of the plate100(100a) and the plate100(100b) are superimposed and butted in the lamination direction. Then, the butted outer peripheral edges are welded by the welding torch16while the plate100(100a) and the plate100(100b) are rotated around the axis of the plate laminated body102(in the circumferential direction of the plates100) by the chuck12. By repeating the same welding process with respect to the plate laminated body102where the plate100(100b) is welded, it is possible to increase the number of laminated plates100that constitute the plate laminated body102.

During welding, the plate100(100b) and the plurality of plates100constituting the plate laminated body102each receive an equal support reaction force from the support14. Therefore, deflection and inclination with respect to the lamination direction due to thermal distortion in welding are corrected by the equal support reaction force applied to each plate from the support14. Thus, it is possible to suppress deflection and inclination with respect to the lamination direction of the plate laminated body102after welding.

In an embodiment, the plurality of plates100constituting the plate laminated body102have the same outer shape and size. Further, as shown inFIG.1, the chuck12is constituted by a pair of chucks12(12a,12b). The pair of chucks12(12a,12b) are mounted on stands20(20a,20b), respectively, and are configured to sandwich the plate100(100b) and the plate laminated body102supported by the support14from both sides in the lamination direction. The stands20(20a,20b) are disposed on a base22and on an upper surface of the base22, a rail24is disposed along a direction of an arrow a. The one stand20(20a) and the support14are fixed to a common frame44, and the frame44is slidable on the rail24in the direction of the arrow a. The other stand20(20b) is fixed on the base22. Further, as shown inFIG.2, the chuck12grips an inner peripheral edge110(seeFIG.6) of the plate100with clicks13.

InFIG.1, in step (1), the frame44is spaced apart from the stand20(20b), and the plate100(100b) is introduced to be mounted to the chuck12(12b). In step (2), the frame44approaches the stand20(20b), and the plate100(100b) and the plate laminated body102are gripped by the chucks12(12a,12b), respectively. In step (3), the outer peripheral edges of the plate100(100a) and the plate100(100b) are welded by the welding torch16. In step (4), the frame44separates from the stand20(20b).

Herein, a producing step of the plate structure102(102a) as an embodiment of the plate laminated body102will be described. The plate structure102(102a) is used as a heat exchanging part of a shell-and-plate type heat exchanger.FIG.6shows a producing step of the heat exchanging part illustrated in FIG. 13 of Patent Document 1. In this example, as the plate100, the plate100(100A) having a perfect circular outer shape is used. In each of the plurality of perfect circular plates100(100A), protrusions and recesses104having a waveform cross-section are formed. In the plate100(100A), two refrigerant flow holes108whose phases are different by 180 degrees with reference to the center are drilled in the vicinity of an outer peripheral edge106. The outer peripheral edge106of the plate100(100A) and inner peripheral edges110of the plate100(100A) forming the refrigerant flow holes108are formed in a narrow annular flat surface connected to the protrusions and recesses104. A plate-like body forming a flat surface of the outer peripheral edge106and plate-like bodies forming flat surfaces of the inner peripheral edges110have a height difference by a step between the protrusion and the recess of the protrusions and recesses104.

First, the two plates100(100A) are superimposed with back surfaces thereof being opposite to each other (with the protrusions or the recesses of the protrusions and recesses104being arranged back-to back), and the inner peripheral edges110of the refrigerant flow holes108arranged to face each other are circumferentially welded as indicated by an arrow u, thereby producing a pair plate112. At this time, between the outer peripheral edges106of the adjacent plates100(100A), a gap s is formed which is twice the size of the step between the protrusion and the recess of the protrusions and recesses104formed in the plates100(100A). Next, for example, using the welding device10, the plurality of pair plates112are laminated while being supported by the support14, thereby bringing outer peripheral edges of the adjacent pair plates112into contact with each other. At this stage, a laminated body constituted by the pair plates112as an embodiment of the plate laminated body102is formed. Further, the outer peripheral edges which are in contact with each other are circumferentially welded as indicated by an arrow v, thereby producing the plate structure102(102a). The plate structure is immersed in a refrigerant stored in a hollow container of the shell-and-plate type heat exchanger.

As described above, the plate structure102(102a) is produced by alternately welding the inner peripheral edges110of the refrigerant flow holes108and the outer peripheral edges106of the plurality of plates100in the lamination direction. Consequently, on one surface side of each plate, a first flow path opened to an interior space of the above-described hollow container, and a second flow path closed with respect to the interior space of the hollow container and communicating with the refrigerant flow holes108are formed. Then, a first refrigerant flowing through the first flow path and a second refrigerant flowing through the second flow path can exchange heat via the plates. The plates100constituting the plate structure102(102a) may be the non-circular plates100(100B), as shown inFIG.2.

As shown inFIG.3, a producing method for the plate structure102(102a) according to an embodiment first prepares at least two sets of pair plates112each of which is constituted by a pair of plates100joined such that the outer peripheral edges thereof are superimposed in a front view (preparation step S10). The pair plate112is produced by, for example, the procedure shown inFIG.6. Next, the two sets of pair plates112are arranged such that the outer peripheral edges106of the plates100arranged to face each other between the two sets of pair plates112are butted. These two sets of pair plates112are gripped from both sides by the chucks12(12a,12b) in the horizontal position, and are supported from below by the support14(positioning step S12). Subsequently, the two sets of pair plates112positioned by the support14are rotated in the circumferential direction (around the axis) of the pair plates112, and the outer peripheral edges106of the plates100butted to each other are welded by the welding torch16, thereby producing the plate structure102(102a) (welding step S14). By repeating the above-described process with respect to the produced plate structure102(102a), it is possible to increase the number of pair plates112that constitute the plate structure102(102a).

With the above method, during welding, since the plurality of pair plates112in the horizontal position are supported from below by the support14, each of the plurality of pair plates112receives the equal support reaction force from the support14. Thus, deflection and inclination with respect to the lamination direction due to thermal distortion in welding are corrected by the equal support reaction force applied to each pair plate112from the support14. Thus, it is possible to produce the plate structure102(102a) without any deflection and inclination with respect to the lamination direction.

In the embodiment shown inFIG.1, first, in step (1), the plate structure102(102a), which is produced by the outer peripheral edges106of the plates100arranged to face each other between the two sets of pair plates112that have already been butted and welded, is supported from below by the support14. Moreover, one end of the plate structure102(102a) is gripped by the chuck12(12a). The stand20(20a) is at a position away from the stand20(20b) in the direction of the arrow a. Meanwhile, still another set of pair plates112is introduced into the welding device10and is gripped by the chuck12(12b). Next, in step (2), the chuck12(12a) and the support14move toward the chuck12(12b), and the plate structure102(102a) and the new pair plate112are in a positional relationship allowing the outer peripheral edges of the adjacent plates100to undergo butt welding.

Next, in step (3), the outer peripheral edges of the plates100butted between the adjacent pair plates112are welded over the entire circumference by the welding torch16disposed on the radially outer side of the plate structure102(102a), thereby producing the plate structure102(102a) where the new pair plate112is added to the existing plate structure102(102a). In step (4), after the welding, the plate structure102(102a) is removed from the chuck12(12b), and the chuck12(12a) and the support14each return to the original position, that is, the stand20(20a) returns to the position away from the stand20(20b). Then, the process returns to step (1), and a further new set of pair plates112is prepared and gripped by the chuck12(12b).

In an embodiment, as shown inFIG.1, the chuck12(12a,12b) is configured to be able to rotate the gripped plate100(100b) and the plate laminated body102around the axis of a rotational shaft18, that is, about a rotation center O along the lamination direction. A device (not shown) for rotating the chuck12(12a,12b) is disposed in the stand20(20a,20b). Further, the support14is constituted by a support roller. Thus, in the welding process, the support14can rotatably support the supported plate100(100b) and the plate laminated body102. Therefore, with the welding torch16fixed at a fixed position on the outer side of the plate100(100b) and the plate laminated body102, it is possible to easily weld the outer peripheral edges of the adjacent plates100between the plate100(100b) and the plate laminated body102, while rotating the plate100(100b) and the plate laminated body102.

In an embodiment, the support14constituted by the support roller is configured to make a driven rotation in accordance with rotations of the supported plate laminated body102and the like. Thus, each of the plurality of plates100constituting the plate laminated body102does not receive an extra force from the support roller, making it possible to suppress occurrence of distortion and deformation in the outer peripheral edge106of each plate100.

In an embodiment, as shown inFIG.2, the support14is constituted by the first support14(14a) and the second support14(14b) disposed on both sides of a vertical surface Sv passing through the rotation center O of the chuck12. Thus, it is possible to stably support the plate laminated body102and the like.

In an embodiment, as shown inFIG.4, the welding device10includes a drive part26for moving the support14along the vertical direction. A control part28controls the operation of the drive part26and controls a support height of the support14based on a rotation angle of the chuck12. When the plurality of plates100constituting the plate laminated body102are the non-circular plates100(100B) as shown inFIG.2, a length r from the rotation center O of the chuck12to the outer peripheral edge106varies depending on the rotation angle of the chuck12. According to the present embodiment, since the control part28controls the support height of the support14based on the rotation angle of the chuck12, even if the plate100is the non-circular plate100(100B), it is possible to adjust the support height of the support14in accordance with the shape of the non-circular plate100(100B). Therefore, even in a case where the plate laminated body102constituted by the non-circular plates is welded, it is possible to weld the outer peripheral edges of the plates constituting the plate laminated body102while keeping the rotation center O of the plate laminated body102at the fixed position.

In an embodiment, as shown inFIG.4, an angle sensor30for detecting the rotation angle of the chuck12is provided, and the detected value by the angle sensor30is sent to the control part28. The control part28controls the support height of the support14based on the detected value sent from the angle sensor30.

In an embodiment, as shown inFIG.4, the drive part26includes a servomotor32, and ball screws34disposed along the vertical direction and supporting the support14. Power of the servomotor32is transmitted to the ball screws34via a power transmission part36. The support14moves vertically by the power transmitted from the power transmission part36. By the drive part26of the above-described configuration, it is possible to accurately adjust the vertical position of the support14with the simple configuration.

In an embodiment, as shown inFIG.4, the power transmission part36includes a gear38mounted on an output shaft of the servomotor32, and gears40where screw portions formed in center through holes screw with the ball screws34, respectively. The gear38and the gears40engage with each other, transmitting the rotation of the output shaft of the servomotor32to the ball screws34and allowing the ball screws34to move vertically.

In an embodiment, the two gears40are disposed across the gear38along the lamination direction. Thus, it is possible to vertically move the support14extending along the lamination direction without being inclined in the horizontal direction.

In an embodiment, as shown inFIG.4, the support14is constituted by the support roller, the welding device10includes a seat42for rotatably supporting the support roller, and the seat42is fixed to the frame44. The upper end portion of each ball screw34penetrates a through hole formed in the frame44and is coupled to the seat42. Thus, the support14can vertically move together with the seat42. As described above, since the ball screw34is coupled to the seat42, an extra load is not applied to the support14. Thus, it is possible to accurately hold the support14at the support position.

The welding device10also includes a pair of guide shafts46,46disposed on the outer side of the gears40in the lamination direction along the vertical direction, and a pair of guides48,48each having a through hole where a corresponding one of the guide shafts46slidably penetrates. The upper end portion of each guide shaft46is coupled to the seat42, and the upper end portion of each guide48is coupled to the frame44. With the guide shafts46and the guides48, it is possible to smoothly perform vertical movement of the support14.

In an embodiment, as shown inFIG.4, the plate laminated body102detects the load applied to the support14, and the control part28is configured to control the support height of the support14in consideration of a detected value of the load besides the rotation angle of the chuck12. Thus, during welding, with the support14, it is possible to apply a constant load to the outer peripheral edges106of the plurality of plates100constituting the plate laminated body102in the entire circumferential region. Further, it is possible to control the support height of the support14while grasping a variation in load of the plate laminated body102due to an individual difference such as the weight of each plate100. Therefore, it is possible to support the plate laminated body102without causing partial deflection and depressions in the outer peripheral edges106.

In an embodiment, as shown inFIG.4, the welding device10includes a load sensor50for detecting the load applied to the support14by the plate laminated body102, and the detected value by the load sensor50is sent to the control part28. The control part28is configured to control the support height of the support14based on the detected value sent from the load sensor50.

In an embodiment, the control part28is configured to control the operation of the drive part26and to control the support height of the support14in consideration of a value of a drive current supplied to the servomotor32besides the rotation angle of the chuck12. The value of the drive current supplied to the servomotor32represents a load applied to the support14by the plate laminated body102. Therefore, by detecting the value of the drive current supplied to the servomotor32, it is possible to easily grasp the variation in load of the plate laminated body102due to the individual difference such as the weight of each plate100.

In an embodiment, as shown inFIG.2, the plate laminated body102is constituted by, as the plates100, the plurality of non-circular plates100(100B) laminated with the same outer shape. Even if the plates100constituting the plate laminated body102are the non-circular plates100(100B), since the plate laminated body102in the horizontal position is welded while being supported from below by the support14, the plurality of non-circular plates100(100B) constituting the plate laminated body102receives a reaction force equal to the self-weight of the plate laminated body102from the support14. Thus, deflection and inclination with respect to the lamination direction (the axis direction of the rotational shaft18) caused by thermal deformation in welding are corrected by the support14. Thus, it is possible to suppress deflection and inclination with respect to the lamination direction of the plate laminated body102after welding.

In an embodiment, the plate laminated body102is formed by laminating at least two sets of pair plates112each of which is constituted by a pair of non-circular plates100(100B) joined such that the outer peripheral edges106are superimposed in the front view.

In an embodiment, as shown inFIG.2, the welding torch16,16′ is disposed above the plate laminated body102and is configured to be able to perform downward welding.

Thus, it is possible to suppress sag of a welding bead due to an influence of gravity, and to suppress poor welding.

FIG.5is an explanatory diagram showing in sequence the welding step of the plate laminated body102constituted by the non-circular plates100(100B). In the diagram, a numerical value shown below each drawing indicates a rotation angle θ of the chuck12. As shown in the diagram, in the case of the plate laminated body102constituted by the non-circular plates100(100B), since the length r from the rotation center θ to the plate outer peripheral edge106supported by the support14(14a,14b) varies depending on the rotation angle θ of the chuck12, the support height of the support14(14a,14b) is adjusted by the control part28. Thus, it is possible to weld the outer peripheral edges106of the adjacent non-circular plates100(100B) while fixing the rotation center O of the plate laminated body102.

INDUSTRIAL APPLICABILITY

According to some embodiments of the present disclosure, when producing a plate structure or the like which is applicable to, for example, a heat exchanging part of a shell-and-plate type heat exchanger by welding a plate laminated body, it is possible to suppress deflection and inclination with respect to a lamination direction due to thermal deformation during welding. Therefore, if the plate structure or the like is applied to the above-described heat exchanging part, it is possible to accurately form flow paths for refrigerants flowing through both sides of a plate as designed, making it possible to maintain heat exchange efficiency high.

REFERENCE SIGNS LIST

10Welding device12(12a,12b) Chuck13Click14(14a,14b) Support14aFirst support14bSecond support16,16′ Welding torch18Rotational shaft20(20a,20b) Stand22Base24Rail26Drive part28Control part30Angle sensor32Servomotor34Ball screw36Transmission part38,40Gear42Seat44Frame46Guide shaft48Guide50Load sensor100(100a,100b) Plate100A Non-circular plate100B Perfect circular plate102Plate laminated body102(102a) Plate structure104Protrusions and Recesses106Outer peripheral edge108Refrigerant flow hole110Inner peripheral edge112Pair plateO Rotation centerθ Rotation angle