Alignment of individual workpieces

Abstract

To provide a robust, fast, and accurate device for aligning individual workpieces with reduced technical complexity. [Solution] The workpiece aligner comprises a base and an actuation assembly for moving a workpiece support, the actuation assembly comprising a first rotary actuator, a second rotary actuator, and a third rotary actuator, each rotary actuator driving a cammed rotor that moves the support relative to the base, so that when rotated, the actuation assembly can selectively operate to move the support to cause translation of the support parallel to a plane, rotation of the support around an axis perpendicular to the plane, or a combination of the translation and the rotation.

Description

Technical Field

[0001] The present invention relates to a workpiece aligner, an alignment assembly, and a mounting portion for supporting one or more workpiece aligners.

Background Art

[0002] Industrial screen printing machines typically apply a conductive printing medium, such as solder paste or conductive ink, through a pattern of apertures (also referred to as a foil or stencil) in a printing screen using an angled blade or squeegee to a planar workpiece such as a circuit board. When the area of the pattern is relatively small compared to the area of the screen, the screen can contain two or more patterns, thereby enabling two or more areas of a substrate or two or more substrates to be printed simultaneously using the same screen. Alternatively, two or more relatively small screens may be used within the same printing machine such that each screen can be used to simultaneously print two or more areas of a substrate or two or more substrates.

[0003] The currently preferred technique is to pre-separate or "singulate" individual substrates prior to the printing process. This process has the advantage that all substrates with defects are identified and quickly excluded prior to printing so that only defect-free substrates are printed. This process is relatively efficient but introduces complexity. Specifically, it is difficult to both support and align individual relatively small substrates for simultaneous (or sequential) printing.

[0004] Various methods have been developed to overcome these problems. For example, Patent Document 1 describes a method in which each substrate is positioned individually, but this only allows for continuous printing on one substrate at a time. Patent Document 2 describes a method in which the position of each substrate is individually confirmed and each substrate is continuously repositioned using a repositioning arm. This technique allows all substrates on a panel to be printed simultaneously, but it requires additional equipment (i.e., a positioning arm), and moving the arm between workpieces is time-consuming. Patent Document 3 describes an alternative device in which all substrates can be aligned simultaneously using a reference webbing and then printed simultaneously. This solution works well, but it is not suitable if incoming unprinted substrates are positioned too far from their correct position.

[0005] A workpiece support assembly capable of supporting and individually aligning a number (one or more) relatively small workpieces (commonly referred to as “fragmented” workpieces) is described in Patent Document 4. Figure 1 schematically shows an example of such an assembly 1, where the assembly 1 comprises a 2x4 array of individual support “towers” ​​2. Each tower 2 has a support surface 3 on which a workpiece (not shown) can be supported during a printing operation. Furthermore, each tower 2 is individually actuated to move in orthogonal directions X and Y, typically in the horizontal plane, and also to rotate around an orthogonal Z axis typically extending vertically to provide so-called theta correction. As described in Patent Document 4, such movement can be advantageously provided through the use of a parallel kinematic actuation system in each tower. Other arrays of larger or smaller scales are, of course, possible. This system has been published by ASMPT under the name “MASS” and provides a very fast and accurate printing solution. Further extending the MASS methodology, Patent Document 5 describes how the use of support surfaces of different heights in each MASS tower can reduce the minimum pitch at which a workpiece can be printed in a single printing operation by staggering the alignment of the workpieces. While MASS can be considered the "optimal standard" for fragmented systems, the use of such individually operable towers is technically complex and requires a specific minimum pitch between towers so that they can move relative to each other without the risk of collision and can accommodate the physical space required for the hardware. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] UK Patent Application Publication No. 2484373 [Patent Document 2] Japanese Patent Publication No. 2009-248551 [Patent Document 3] International Publication No. 2014 / 166956 [Patent Document 4] European Patent Application Publication No. 3693168 [Patent Document 5] UK Patent Application Publication No. 2619961 [Patent Document 6] European Patent Application Publication No. 3895895 [Overview of the project] [Problems that the invention aims to solve]

[0007] The present invention aims to provide a robust, fast, and accurate alternative device for aligning fragmented workpieces, with reduced technical complexity. Furthermore, it aims to provide an alignment device capable of aligning fragmented substrates at a very small pitch of approximately 31.6 mm, considerably smaller than the pitch achievable with previously available alignment devices. A further objective of the present invention is to provide such a device in a modular form. [Means for solving the problem]

[0008] According to the present invention, this objective is achieved by a novel operating system that includes the alignment of rotary actuators that drive each cam-equipped rotor. The resulting workpiece aligner is small, robust, and can be adapted to a modular mounting configuration.

[0009] According to a first aspect of the present invention, a workpiece aligner for aligning a supported workpiece, The base and, Support section for supporting the workpiece, An operating assembly for moving the support part, Equipped with, The operating assembly comprises a first rotary actuator, a second rotary actuator, and a third rotary actuator, and each rotary actuator, when rotated, The operating assembly is designed to move the support so that it can be selectively operated to cause translation of the support parallel to the plane, rotation of the support around an axis perpendicular to the plane, or a combination of the translation and the rotation. A workpiece aligner is provided that drives each cam-equipped rotor, which moves the support portion relative to the base.

[0010] According to a second aspect of the present invention, an alignment assembly is provided for aligning a plurality of individualized substrates, each comprising a plurality of workpiece aligners according to the first aspect.

[0011] According to a third aspect of the present invention, a mounting portion for supporting one or more workpiece aligners, the mounting portion comprising a top surface having one or more docks for receiving each workpiece aligner in a releasable and repeatable manner, Each dock is equipped with electrical contacts for exchanging electrical signals with its respective workpiece aligner, and a vacuum port for aligning with the vacuum opening of its respective workpiece aligner when it is received into the dock. The mounting section is provided, which includes a pneumatic manifold for providing at least partial vacuum to each of the workpiece aligners supported by the mounting section via their respective vacuum ports.

[0012] Other specific aspects and features of the present invention are described in the appended claims.

[0013] The present invention will now be described with reference to the accompanying drawings (not to exact scale). [Brief explanation of the drawing]

[0014] [Figure 1] This is a schematic isometric view of a known workpiece support assembly. [Figure 2] This is a schematic isometric view of a workpiece aligner according to an embodiment of the present invention. [Figure 3] It is a schematic view from above of the cross section of the workpiece aligner in FIG. 2. [Figure 4] It is a schematic view from below of the head of the workpiece aligner in FIG. 2. [Figure 5] It is a schematic isometric view from above of the head in FIG. 4. [Figure 6] It is a schematic view from above of the cross section of the workpiece aligner according to the second embodiment of the present invention. [Figure 7A] It is a schematic view from the side of a part of the operating assembly according to the third embodiment of the present invention. [Figure 7B] It is a schematic view from the side of a part of the operating assembly according to the third embodiment of the present invention. [Figure 8A] It is a schematic view from the side of a part of the operating assembly according to the fourth embodiment of the present invention. [Figure 8B] It is a schematic view from the side of a part of the operating assembly according to the fourth embodiment of the present invention. [Figure 9] It is a schematic view from above of the cross section of the workpiece aligner according to the fifth embodiment of the present invention. [Figure 10] It is a schematic view from above of the cross section of the workpiece aligner head according to the sixth embodiment of the present invention. [Figure 11] It is a schematic view from above of the cross section of the workpiece aligner head according to the seventh embodiment of the present invention. [Figure 12] It is a schematic view from above of the cross section of the workpiece aligner head according to the eighth embodiment of the present invention. [Figure 13] It is a schematic view from above of the cross section of the workpiece aligner head according to the ninth embodiment of the present invention. [Figure 14] It is a schematic isometric view of the operating assembly of the workpiece aligner according to the tenth embodiment of the present invention. [Figure 15] It is a schematic view from above of the operating assembly in FIG. 14. [Figure 16] It is a schematic view showing a part of the cross section of the workpiece aligner from the side according to the tenth embodiment. [Figure 17] Figure 16 is a schematic exploded view from above of a portion of the workpiece aligner. [Figure 18] This is a schematic isometric view of a part of the alignment assembly according to the present invention. [Figure 19] Figure 18 is a schematic isometric view of the cross-section of the alignment assembly. [Figure 20] This is a schematic cross-sectional side view of the alternative alignment assembly. [Modes for carrying out the invention]

[0015] A workpiece aligner (or "tower") 10 according to a first embodiment of the present invention is schematically shown in Figure 2. The workpiece aligner 10 can form part of a workpiece support assembly 100 (see, for example, Figure 14 later). The workpiece aligner 10 is suitable for supporting a single pieced workpiece (not shown) or, furthermore, for supporting two or more pieced workpieces (for example, using a methodology similar to that described in Patent Document 5). For the sake of brevity, in the following description, we will assume that each workpiece aligner 10 is used to hold its respective single pieced workpiece.

[0016] The workpiece aligner 10 includes a base 12 that remains stationary during operation and can be placed, for example, on the tool table (not shown) of a printing machine within a mounting section 102 (see, for example, Figure 14 later). The illustrated base 12 has an approximately square cross-section formed by wall sections enclosing a hollow interior to create a hollow cylinder. A head 14 is provided projecting above the base 12 and is movable relative to the base 12 in the horizontal XY plane shown in Figure 2. Although not shown in Figure 2 for clarity, one or more bearings may be positioned between the base 12 and the head 14 to ensure smooth relative movement between the base 12 and the head 14. In Figure 2, both the base 12 and the head 14 are shown transparent and therefore dashed lines so that the internal structure of the workpiece aligner 10 can be seen more clearly. The head 14 has an upper surface that acts as a support 16 for the workpiece during use. Housed within the base 12 is an operating assembly comprising a first rotary actuator 18A, a second rotary actuator 18B, and a third rotary actuator 18C or motor, each driving a cammed rotor 22A-22C via a shaft 20. Conveniently, stepping motors can be used as each actuator 18A-18C. Each rotary actuator 18A-18C drives its respective cammed rotor 22A-22C around its respective axis of rotation, which is oriented perpendicular to the horizontal XY plane, such that the rotary actuators 18A-18C and, consequently, the shaft 20, are aligned parallel to the vertical Z-axis. In Figure 2, the cammed rotors 22A-22C are shown as having a circular cross-section mounted eccentrically with respect to the shaft 20, but the cammed rotors 22A-22C can take various forms, as is technically well known, where the rotor's driving surface is at a radial distance from the axis of rotation that changes with the azimuth angle. The cam-equipped rotors 22A-22C protrude, at least partially, into the cavity 26 (see Figure 3) formed within the head 14, as will be described in more detail later.Each cammed rotor 22A-22C also supports a radially projecting stop member 24, which is used to hold the stepping motor still during calibration procedures when the stepping motor is used as an actuator 18A-18C. More specifically, each stop member 24 is positioned below the head 14 within the body 12 and is positioned such that the range of rotational movement of each cammed rotor 22A-22C is defined by the physical contact of each stop member 24 with a stop surface (not shown) formed in or supported by the wall area of ​​the base 12.

[0017] Figure 3 schematically shows a cross-section of the workpiece aligner of Figure 2, viewed from above, along line AA of Figure 2, which penetrates the vertical thickness of the head 14 by approximately half. For clarity, the rotary actuators 18A-18C are hidden. In this figure, the eccentricity of each cammed rotor 22A-22C relative to their respective shafts 20 is more clearly visible. Also more clearly visible is the internal structure of the head 14. The head 14 has an internal cavity 26 formed by the planar top surface of the head 14 and the side walls 28 (see also Figure 5, where the structure of the side walls 28 is clearly shown). The bottom of the cavity 26 is open so that the cammed rotors 22A-22C can protrude upward into the cavity 26. The biasing means in the form of three permanent magnets 30 are positioned within the side wall 28, each adjacent to each of the cammed rotors 22A to 22C, so that each of the cammed rotors 22A to 22C, which may be formed from or have a portion of a ferromagnetic material such as steel or iron, is subjected to an attractive force to each of the permanent magnets 30. In this method, the head 14, more specifically the side wall 28, is maintained in contact with each of the cammed rotors 22A to 22C, thereby moving with the cammed rotors 22A to 22C over its range of motion, with the side wall 28 acting simultaneously as a drive for each of the cammed rotors 22A to 22C. As can be seen in Figure 3, the synchronously rotating cammed rotors 22A and 22C cause the head 14 to translate parallel to the illustrated horizontal Y-axis, while the cammed rotor 22B remains stationary. The rotating cam rotor 22B causes the head 14 to translate parallel to the illustrated horizontal X-axis, while keeping the cam rotors 22A and 22C stationary. The rotation of the head 14 around a vertical axis parallel to the illustrated Z-axis, i.e., the rotation of the head 14 around the illustrated angle θ, can be achieved, for example, by rotating the cam rotors 22A and 22B while keeping the cam rotor 22C stationary, or by rotating the cam rotors 22A and 22C relatively (for example, in opposite directions).Therefore, the selective operation of the working assembly, that is, the selective rotation of each of the cammed rotors 22A to 22C, results in a controllable translation of the head parallel to the horizontal plane, and consequently, a controllable translation of its support, rotation of the support around a vertical axis perpendicular to the horizontal plane, or a combination of the translation and rotation, with the magnitude of these movements determined by the range of rotation of the cammed rotors 22A to 22C.

[0018] Also visible in Figure 3 is a “utility passage” 32 that extends along the vertical length of the workpiece aligner 10. As previously described, the operating assembly comprises three rotary actuators 18A to 18C arranged parallel to each other within a generally square installation area. Therefore, the base 12 has a “dead space” in the lower right quarter of the base 12, as illustrated in this case, where no rotary actuators are present. This space, or utility passage 32, can be advantageously used to accommodate other components. These components may include: i) Electronic circuits and / or electrical connections used to control the rotary actuators 18A to 18C. In this case, such electrical connections can be connected to electrical contacts, such as spring-loaded contact pins (often referred to as "pogo pins") 42 located at the lower end of the base 12 (see Figure 15). These can transmit power as well as control signals from an external control unit (not shown), such as a computer or processing unit. ii) A first vacuum passage 34 and a second vacuum passage 36 extending along the vertical length of the base 12, remaining fluidly isolated from each other, as shown in the illustration. More specifically, each of the first vacuum passage 34 and the second vacuum passage 36 may open at the respective first vacuum opening 38 and second vacuum opening 40 (see Figure 15) at the lower end of the base 12 to receive at least partial vacuum, as will be described in more detail later. The first vacuum passage 34 can be used, for example, to selectively supply at least partial vacuum to the upper surface of the support 16 in order to releasably fix a workpiece (not shown) during use and to prevent relative movement between the workpiece and the support 16. The second vacuum passage 36 can be used, for example, to selectively supply at least partial vacuum onto the base 12, thereby reducing the fluid pressure between the base 12 and the head 14, which acts to lock the head 14 to the base 12 and prevent relative movement between them. This can be achieved by applying at least a partial vacuum to the interior of the base 12, or more preferably by applying a vacuum through a plurality of openings 37 formed in the wall of the base 12 and inherent in the side wall 28 of the head 14 (the openings 37 are shown as dashed lines in Figure 3 to indicate that they are not directly visible in Figure 3), and the openings 37 are in fluid communication with the second vacuum passage 36 such that when a vacuum is applied through the second vacuum passage 36 and the openings 37, the side wall 28 of the head 14 is pulled down and locked in the base 12. This locking can be applied when the alignment is complete, i.e., when the head 14 has been moved to the required horizontal position relative to the base 12. To accommodate the relative movement between the base 12 and the head 14, the first vacuum passage 34 and the second vacuum passage 36 can be formed from a flexible and preferably elastically deformable material, such as an elastomer material like rubber or synthetic rubber, formed as tubes. The tube may optionally be bellows-shaped to facilitate adaptation in the event of relative vertical movement between the base 12 and the head 14.

[0019] The structure of the head 14 itself can be seen more clearly in the isometric views from below in Figure 4 and from above in Figure 5. In Figure 5, the internal structure of the head 14, namely the side walls 28 and the magnet 30, is shown by dashed lines.

[0020] Figure 6 schematically shows a cross-section of a workpiece aligner (or tower) 50 according to a second embodiment of the present invention, viewed from above. Many of the components are the same as those described with respect to the first embodiment, and therefore, the reference numerals are retained where possible.

[0021] In this second embodiment, the cammed rotors 52A to 52C have an alternative configuration, comprising rotors with a radius that changes around a central point. Thereafter, stepped portions 54 with abruptly changing radius are formed on the circumferential surface of each cammed rotor 52A to 52C. This design of the cammed rotor has the advantage that the displacement of the head 14 relative to the base 12 can be quickly changed by moving the stepped portions 54 across the contact points with the side walls 28 of the head. Such cams can be manufactured with great precision, for example, using an electrical discharge machining method.

[0022] For clarity, the stop member is omitted from Figure 6, but it may be provided, for example, attached to the shaft 20 below the cam-equipped rotor (at a smaller Z value), and can function in the same manner as in the first embodiment.

[0023] Figures 7A and 7B schematically show a part of the operating assembly according to a third embodiment of the present invention from a side view, and Figures 7A and 7B show the cammed rotor 56 of the operating assembly at different rotational positions.

[0024] The rotary actuator is capable of rotating the shaft 20 around a vertical axis of rotation, i.e., an axis of rotation parallel to the illustrated Z-axis, in this case where only one rotary actuator 18A is shown. Bearings 60 may be provided at each end of the shaft 20 to assist the rotation and ensure that the shaft 20 remains vertical throughout its rotation. The bearings 60 can also act as stoppers that define the range of movement of the cammed rotor 56.

[0025] The cammed rotor 56 is mounted on the shaft 20 to rotate with the shaft 20, but can move perpendicularly (parallel to the Z-axis) along the shaft 20, for example, by providing the shaft 20 with external splines (not shown) positioned within internal splines or grooves (not shown) in the cammed rotor 56. The cammed rotor 56 has two combined regions, namely an upper cam region 62 and a lower thread region 64. The cam region 62 has a vertically oriented external cam surface that is helical in shape, such that its radius changes with respect to the azimuth angle around the axis of rotation and over its vertical extension. The thread region 64 has a constant radius with male threads.

[0026] A guide pin 68, fixedly mounted on the base 12 (not shown), engages with the threads of the threaded section 64 such that the rotation of the cammed rotor 56 causes the corresponding upward or downward movement of the cammed rotor 56 relative to the base 12. A cam follower 66, mounted on the head 14 (not shown), engages with the outer cam surface of the cam section 62. Thus, the upward or downward movement of the cammed rotor 56 causes the horizontal movement of the cam follower 66, and consequently the horizontal movement of the head 14.

[0027] Figures 8A and 8B schematically show a part of the actuation assembly according to a fourth embodiment of the present invention from a side view, and Figures 8A and 8B show the cammed rotor 58 of the actuation assembly at different rotational positions.

[0028] The rotary actuator is capable of rotating the shaft 20 around a vertical axis of rotation, i.e., an axis of rotation parallel to the illustrated Z-axis, in this case where only one rotary actuator 18A is shown. Bearings 60 may be provided at each end of the shaft 20 to assist the rotation and ensure that the shaft 20 remains vertical throughout its rotation. The bearings 60 can also act as stoppers that define the range of movement of the cammed rotor 58.

[0029] The cammed rotor 58 is mounted on the shaft 20 to rotate with the shaft 20, but can move perpendicularly (parallel to the Z-axis) along the shaft 20, for example, by providing the shaft 20 with external splines (not shown) positioned within internal splines or grooves (not shown) in the cammed rotor 58.

[0030] The cammed rotor 58 has a vertically oriented external cam surface, which is helical in shape, formed thereon, such that its radius varies with respect to the azimuth angle around the axis of rotation and over its vertical extension. The cam surface is threaded to receive a cam follower 66 mounted on a head 14 (not shown) and fixed in the Z direction, thus restricting the vertical movement of the cam follower 66.

[0031] The rotation of the cammed rotor 58 causes a corresponding upward or downward movement of the cammed rotor 58 relative to the base 12. This upward or downward movement of the cammed rotor 58 causes horizontal movement of the cam follower 66, and consequently, horizontal movement of the head 14.

[0032] Figure 9 is a schematic cross-sectional view from above of a workpiece aligner (tower) 70 according to a fifth embodiment of the present invention. This embodiment is similar to the embodiment shown in Figure 6, except that tension springs are used as biasing means to bring the head 14 into contact with the cammed rotors 52A-52C instead of magnets. More specifically, a plurality of horizontal springs 72, in this case three, are connected between the base 12 and the head 14, causing the head 14 and the cammed rotors 52A-52C to face each other in the horizontal (XY) plane. Alternatively, a plurality of vertical springs 74, in this case two, are connected between the base 12 and the head 14 at different vertical heights, causing the head 14 and the base 12 to face each other in the vertical (Z) direction. Each spring 72, 74 is connected at its respective end to a column 76 fixed to the head 14 or the base 12. In the case of the horizontal springs 72, the column in the base 12 can be conveniently formed on the shaft 20, as shown. The use of spring 72 may cause wear on the side wall 28 of head 14; therefore, if necessary, a reinforcing plate or the like (not shown) may be fixed to the side wall 28 adjacent to the cam-equipped rotor 52A-52C toward contact with spring 72 in order to reduce such wear.

[0033] The embodiments described above use means such as magnets or springs to bring the head into contact with the cammed rotor. Four embodiments described below and illustrated with reference to Figures 10 to 14 respectively avoid the use of such biasing means by using alternative head configurations having at least one recess sized to comfortably receive at least one cammed rotor so that one or more recesses act as cam followers. In each case, the recess has an elastically deformable side wall to ensure good contact between the recess and the respective cammed rotor. In all of these figures, the cammed rotor is shown within the recess. Utility passages are omitted for clarity, but it will be understood that such passages may be provided in a manner similar to those described above.

[0034] Figure 10 schematically shows a cross-section of a workpiece aligner head 15 according to a sixth embodiment of the present invention, viewed from above. As shown, the head 15 has two recesses 130, 132 formed therein, with two cammed rotors 134A, 134B received in recess 130 and a third cammed rotor 134C received in recess 132, and each cammed rotor 134A-134C is driven to rotate around shaft 128 by their respective shafts 128. In this sixth embodiment, the cammed rotors 134A-134C have a non-circular cross-section. Each side wall 136 adjacent to each cammed rotor 134A to 134C is elastically deformable, and the side walls 136 can be conveniently manufactured by forming voids 138, such as hollow regions, adjacent to each side wall 136 and close to their respective recesses 130 and 132, such that the side walls 136 positioned between the cammed rotors 134A to 134C are thin and flexible.

[0035] Figure 11 schematically shows a cross-section of a workpiece aligner head 17 according to a seventh embodiment of the present invention, viewed from above. This embodiment is very similar to the embodiment shown in Figure 10, except that each of the cammed rotors 140A to 140C is of a mirror-symmetric design. Such cammed rotors 140A to 140C function particularly well when housed in recesses 130 and 132.

[0036] Figure 12 schematically shows a cross-section of a workpiece aligner head 19 according to an eighth embodiment of the present invention, viewed from above. This head 19 is very similar to the head 17 in Figure 11, except that the side wall 142 is connected to the rest of the head 19 at one end, so that the associated cavity 138 is open to the associated recesses 130, 132. This form of the head 19 is particularly beneficial for facilitating manufacturing, for example, by enabling a wire cutting manufacturing process in which the cavity 138 is formed simultaneously with its associated recesses 130, 132.

[0037] Figure 13 schematically shows a cross-section of a workpiece aligner head 21 according to a ninth embodiment of the present invention, viewed from above. The head 21 is generally similar to those shown in Figures 11 and 12, except that the side wall 144 has projections extending into associated recesses 146, 148, with a cavity 150 created behind the side wall 144. This type of side wall provides greater flexibility and control over the level of elasticity exhibited by the side wall.

[0038] The workpiece aligner described above provides an alignment mechanism using parallel kinematics. However, the present invention can also provide a non-parallel movement mechanism.

[0039] A tenth embodiment of the present invention using such a non-parallel mechanism is schematically shown in Figures 14 to 17. Figure 14 shows the working assembly of the workpiece aligner 80 in an isometric view, Figure 15 shows the working assembly of Figure 14 from above, Figure 16 shows the workpiece aligner 80 in a partial cross-sectional view from the side, and Figure 17 shows a part of the workpiece aligner 80 in an exploded view from above.

[0040] In this embodiment, three separate rotary actuators 82A to 82C are again used, each rotary actuator 82A to 82C rotatably drives each cammed rotor 84A to 84C, but here, each cammed rotor 84A to 84C engages with a separate alignment member, each alignment member being movable in a specific direction.

[0041] As is most clearly shown in Figures 14 and 16, the rotary actuators 82A to 82C are positioned at different heights, with rotary actuator 82A being inverted relative to rotary actuators 82B and 82C such that its shaft 20 and cammed rotor 84A are close to the base of the workpiece aligner 80.

[0042] Both rotary actuators 82A and 82B are mounted on a body 86 (see Figure 16), which is rotatably mounted on a base 88 via a shaft 90, with a bearing 92 receiving the shaft 90. A cammed rotor 84A engages with the surface of the base 88. The cammed rotor 84B, driven by rotary actuator 82B, engages with the surface of the intermediate layer 94. Rotary actuator 82C is mounted on the intermediate layer 94 in a hanging manner. The cammed rotor 84C, driven by rotary actuator 82C, engages with the upper layer 96, which carries a support 16 adapted to support a workpiece (not shown).

[0043] Each of the upper layer 96, the intermediate layer 94, and the main body 86 is separated by linear bearings, with only a linear bearing 98 located between the upper layer 96 and the intermediate layer 94, enabling relative motion between them parallel to the illustrated Y-axis, and is visible in Figure 17. The linear bearing between the intermediate layer 94 and the main body 86 is positioned orthogonal to the linear bearing 98 so as to enable relative motion between them parallel to the illustrated X-axis.

[0044] As a result, the base 88, the intermediate layer 94, and the upper layer 96 act as individual alignment members, each driven separately by their respective rotary actuators 82A to 82C. Similar to the previous embodiment, the actuating assembly is selectively operable to move the support 16 to cause translation of the support 16 parallel to the horizontal plane (XY), rotation of the support 16 around a vertical axis perpendicular to the horizontal plane, or a combination of the translation and the rotation.

[0045] The base portion 88 may be placed on a tool table (not shown) via, for example, a mounting portion (for example, reference numeral 102, see Figure 18).

[0046] For example, other functionalities of the workpiece aligner 80, such as electrical signal and vacuum supply capabilities, are the same as those described earlier.

[0047] Figure 18 schematically shows a portion of the alignment assembly 100 according to the present invention in isometric view, and Figure 19 schematically shows a cross-section of the alignment assembly 100 in isometric view. The alignment assembly 100 comprises a plurality of workpiece aligners 10, 50, 70, 80 as previously described, but in Figure 18 only one workpiece aligner 10 is shown for clarity. Conveniently, each of the plurality of workpiece aligners 10 may be repeatedly mountable and removable on a supporting mounting section 102 such that each workpiece aligner 10 comprises a replaceable module. The mounting section 102 has a top surface in which a plurality of docks 104 are formed, and each workpiece aligner 10 can be released and repeatedly received. Mechanical engagement of each workpiece aligner 10 with the dock 104 to ensure a vertically upright orientation can be achieved in various ways, such as through a good interlocking fit between the edge of the dock 104 and the workpiece aligner 10, or by providing additional mechanical support (not shown). Each dock 104 includes electrical contacts 106 that contact each spring-loaded contact pin 42 (see Figure 19) located on the underside of each workpiece aligner 10. These are provided for exchanging electrical signals with each workpiece aligner 10. Each dock 104 also includes at least one vacuum port that aligns with the vacuum opening of each workpiece aligner 10 when received into the dock 104. In the illustrated embodiment, each dock 104 includes a first vacuum port 108 and a second vacuum port 110 that align with the first vacuum opening 38 and the second vacuum opening 40 of the associated workpiece aligner 10, respectively.

[0048] The mounting section 102 is equipped with a pneumatic manifold for providing at least partial vacuum to each of the vacuum ports 108 and 110, and each pneumatic manifold is fluidically isolated. This can be conveniently achieved by forming the mounting section 102 to be hollow, comprising a fluidically isolated first vacuum chamber 112 and a second vacuum chamber 114, the first vacuum chamber 112 being fluidly connected to each of the first vacuum ports 108, and the second vacuum chamber 114 being fluidly connected to each of the second vacuum ports 110. As shown in the figure, the mounting section 102 is structurally formed from three stacked components: a bottom tray 116, an intermediate tray 118, and an upper cover 120, the first vacuum chamber 112 being formed between the upper cover 120 and the intermediate tray 118, and the second vacuum chamber 114 being formed between the intermediate tray 118 and the bottom tray 116. A passage 122 is formed in the intermediate tray 118 to fluidly connect the second vacuum chamber 114 to the second vacuum port 110.

[0049] At least a partial vacuum can be supplied to each of the first vacuum chamber 112 and the second vacuum chamber 114, for example, through a hole (not shown) extending through the bottom tray 116 to engage with a corresponding hole formed in the tool table, and an additional passage (not shown) fluidly connects the second of the holes to the first vacuum chamber 112. The holes in the tool table may be further connected to one or more vacuum sources, for example, as described in Patent Document 6. Furthermore, the mounting unit can be mechanically fixed to the tool table in various ways, for example, by magnetic force or by a separate reference pin.

[0050] An alternative alignment assembly is schematically shown in Figure 20 in a cross-sectional side view. In this embodiment, each of a plurality of workpiece aligners 10 (similar to, for example, those shown in Figure 2) is supported in a suspension configuration from a mounting unit 160, which may be positioned, for example, on a tool table 162 of a printing machine. The mounting unit 160 comprises a mounting base 164 and a support plate 166 mechanically connected to the mounting base 164, the support plate 166 being positioned vertically above the mounting base 164. The support plate 166 comprises a plurality of through holes 168 extending through it, and each through hole 168 is sized to receive each workpiece aligner 10 such that each workpiece aligner 10 is supported by the support plate 166 in each through hole 168 at a location close to the expansion above the base 12. In this method, the base 12 hangs downward from the support plate 166, and the upper surfaces of each of its support portions 16, i.e., each of the heads 14, protrude upward from the support plate 166. In this case, as shown, the entire heads 14 protrude above the support plate 166 so that the support plate 166 cannot obstruct lateral movement. Although not shown in Figure 20, the necessary electrical and pneumatic connections for the workpiece aligner 10 can be easily routed through the interior of the mounting portion 160. This embodiment is advantageous over the embodiment described earlier in Figure 19 in that it ensures all vertical references of the workpiece aligner 10.

[0051] The embodiments described above are merely illustrative, and other possibilities and alternatives within the scope of the present invention will be apparent to those skilled in the art. For example, each of the acting assemblies of the embodiments described above may be, for example, in the first embodiment, positioned on the head, and inverted such that the cammed rotor protrudes downward into a cavity formed at the base.

[0052] In the embodiments shown in Figures 3 to 9, the sidewalls act as drivers and are in a relatively simple form, contacting each of the cammed rotors near the periphery of the head. However, the present invention is not limited thereto, and alternative layouts of drivers that contact other sides of the cammed rotors may be used. For example, the drivers may have a layout similar to the sidewall 136 shown in Figure 10. In this case, the location of biasing means such as springs (see Figure 9) or magnets (see Figure 6) would need to be adjusted to ensure proper contact.

[0053] Cam rotors can take on a wide variety of forms. For example, a "shallower" cam slope, i.e., a cam surface radius that changes relatively slowly with the angle of rotation, can provide higher resolution and therefore higher positioning accuracy. Conversely, a "steeper" cam slope, i.e., a radius that changes relatively sharply with the angle of rotation, will provide a larger range of positional movement at the cost of lower resolution / accuracy. The "steepness" of a cam rotor may be selected as required for a particular application. Alternatively, a cam rotor may be provided with a cam of a "rate-increasing" or variable slope, such that the radius of the cam surface changes non-linearly with respect to the angle of rotation. For example, the central portion of the rotation range may be provided with a relatively shallow cam slope to provide high resolution in that region, while the portion located at the edge of the rotation range may be provided with a relatively steep cam slope, so that atypical large or "distant" workpieces requiring large translations can be positioned using the same alignment assembly. In fact, the eccentrically mounted cammed rotor with a circular cross-section shown in Figure 3 can already provide such a variable slope effect. Another simple way to achieve this could be to use, for example, an elliptical, lenticular, or similar cammed rotor.

[0054] In the embodiments described above, the head is generally square when viewed from above. However, the head may take other forms to support workpieces of different shapes, such as rectangular or circular.

[0055] For all alignment assemblies according to the present invention, individual workpiece aligners can be calibrated in various ways. A preferred calibration process is carried out inside the printing press using an existing fiducial camera to determine the workpiece alignment at a reference position. Such calibration can be performed as needed, after a predetermined number of alignment / printing operations, or even after each alignment operation. [Explanation of symbols]

[0056] 1. Workpiece support assembly 2 Towers 3 Support surface 10 Workpiece Aligner 12 Base 14 heads 15 heads 16 Support part 17 heads 18A, 18B, 18C Rotary Actuator 19 heads 20 shafts 21 heads 22A, 22B, 22C Cam-equipped rotor 24 Stopping member 26 Cavity 28 Side wall 30 permanent magnets 32 Utility passage 34. First vacuum passage 36. Second vacuum passage 37 Aperture 38 First vacuum opening 40 Second vacuum opening 42. Contact pin under spring load 50 Workpiece Aligner 52A, 52B, 52C Cam-equipped rotor 54 Stepped section 56, 58 Cam-equipped rotor 60 bearings 62 Cam area 64 Threaded area 66 Cam follower 68 Guide pins 70 Workpiece Aligner 72 Horizontal spring 74 Vertical spring 76 pillars 80 Workpiece Aligner 82A, 82B, 82C Rotary Actuator 84A, 84B, 84C Cam-equipped rotor 86 Main Unit 88 Base 90 shaft 92 Bearings 94 Middle Class 96 upper layer 98 Linear bearings 100 Alignment Assembly 102 Mounting section 104 Dock 106 Electrical contacts 108 First vacuum port 110 Second vacuum port 112 First Vacuum Chamber 114 The second vacuum chamber 116 Bottom Tray 118 Intermediate Tray 120 Top cover 122 Passage 128 shaft 130 recess 132 recess 134A, 134B, 134C Cam-equipped rotor 136 Side wall 138 Blank 140A, 140B, 140C Cam-equipped rotor 142 Side wall 144 Side wall 146 recess 148 recess 150 blanks 160 Mounting section 162 Tool Table 164 Mounting base 166 Support plate 168 Through hole

Claims

1. A workpiece aligner for aligning supported workpieces, The base and, A support portion for supporting the workpiece, An operating assembly for moving the support portion, Equipped with, The aforementioned operating assembly comprises a first rotary actuator, a second rotary actuator, and a third rotary actuator, and each rotary actuator, when rotated, The operating assembly is capable of selectively moving the support to cause translation of the support parallel to the plane, rotation of the support around an axis perpendicular to the plane, or a combination of translation and rotation. A workpiece aligner that drives cam-equipped rotors to move the support portion relative to the base portion.

2. The workpiece aligner according to claim 1, wherein each rotary actuator drives its respective cammed rotor around its respective axis of rotation which is oriented perpendicular to the plane.

3. The workpiece aligner according to claim 1, wherein the support portion is positioned on the head, and each of the cammed rotors engages with the head to move the support portion through a parallel kinematic.

4. The workpiece aligner according to claim 3, wherein the head comprises a cavity defined by a side wall, and the cammed rotor engages with the side wall.

5. The workpiece aligner according to claim 3, further comprising a biasing means for biasing the head to contact the cam-equipped rotor, wherein the biasing means optionally comprises a magnet or a spring.

6. The workpiece aligner according to claim 3, wherein the head comprises a recess sized to snugly receive at least one cammed rotor, the recess acting as a cam follower.

7. The workpiece aligner according to claim 6, wherein the recess has an elastically deformable side wall.

8. The workpiece aligner according to claim 2, comprising a plurality of relatively movable alignment members, each of which is engaged by at least one cammed rotor.

9. The workpiece aligner according to claim 8, wherein the operating assembly is positioned between two alignment members, and the support is fixed to one of the plurality of alignment members.

10. The workpiece aligner according to claim 1, further comprising an air pipe extending from the base to the upper surface of the support to provide at least a partial vacuum to the upper surface in order to fix the workpiece to the upper surface of the support during use.

11. The workpiece aligner according to claim 1, further comprising a locking means for locking the support portion to the base portion following alignment, wherein the locking means optionally comprises a vacuum locking portion.

12. An alignment assembly for aligning a plurality of individualized substrates, comprising a plurality of workpiece aligners according to any one of claims 1 to 11.

13. The alignment assembly according to claim 12, wherein the plurality of workpiece aligners are provided on the mounting portion.

14. The alignment assembly according to claim 13, wherein the mounting section comprises a pneumatic manifold for providing at least a partial vacuum to each of the workpiece aligners.

15. The alignment assembly according to claim 13, wherein the mounting section comprises a plurality of docks, and each of the workpiece aligners comprises a module that can be repeatedly mounted on and removed from the dock.

16. The alignment assembly according to claim 13, wherein the mounting portion comprises a mounting base and a support plate mechanically connected to the mounting base, the support plate is positioned vertically above the mounting base, the support plate has a plurality of through holes extending through itself, and each of the through holes is sized to receive each of the workpiece aligners such that each of the workpiece aligners is supported by the support plate in a location close to the upward widening of the base, with the base hanging downward from the support plate, with each of the support portions of the workpiece aligner protruding upward from the support plate.

17. A mounting section for supporting one or more workpiece aligners, The mounting section comprises an upper surface having one or more docks for receiving each workpiece aligner in a releasable and repeatable manner, Each of the docks comprises electrical contacts for exchanging electrical signals with each of the workpiece aligners, and vacuum ports for aligning with the vacuum openings of each of the workpiece aligners when received into the dock. The mounting section comprises a pneumatic manifold for providing at least a partial vacuum to each of the workpiece aligners supported by the mounting section via their respective vacuum ports.

18. Each of the docks is provided with a second vacuum port that aligns with the second vacuum opening of each of the workpiece aligners when it is received into the dock. The mounting section includes a second pneumatic manifold for providing at least a partial vacuum to each of the workpiece aligners supported by the mounting section via each of the second vacuum ports. The mounting section according to claim 17, wherein the pneumatic manifold is fluidically isolated from the second pneumatic manifold.

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