Incremental sheet metal forming system with flexible tooling

Abstract

The present invention relates to a double-sided incremental sheet forming apparatus and method for incrementally forming a sheet such as sheet metal by utilizing a relative primary forming tool assembly and a secondary forming tool assembly and a sheet feed assembly. The primary forming tool assembly includes a rigid tool, and the secondary forming tool assembly includes a compressible and elastic backing layer having a cylindrical or flat configuration. The sheet feed assembly positions the sheet between two forming tools. The rigid tool applies a force to one surface of the sheet, while the elastic backing tool applies a counter force to the opposite surface of the workpiece as it supports the workpiece. This double-sided process localizes the forces on the sheet, so that stresses are advantageously controlled to produce accurately formed asymmetric shapes without the need for expensive molds. Using a rigid tool, both of which have linear independent motion, together with a relative elastic backing tool also avoids potential wrinkling and tearing of the workpiece produced, and enables the forming of a large number of highly retained asymmetric products.

Description

Technical Field

[0001] The present invention relates to an apparatus and method for incrementally forming sheet material, such as sheet metal.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to Provisional Application No. 62 / 844,177, filed May 7, 2019, and claims priority to Provisional Application No. 63 / 006,802, filed April 8, 2020, the entire contents of each of which are hereby incorporated by reference herein. Background Art

[0004] Over the years, many methods have been developed for forming sheet materials (usually metal) into complex shapes. Sheet metal forming technology exists in a wide range of industries and is applied to a variety of metals and plastics. Typical sheet metal parts mass production utilizes coining technology. Coining requires the use of two rigid dies that are machined horizontally with high accuracy. The sheet of material (i.e., the workpiece) is pressed between the two dies to form the material into the desired configuration established by the dies.

[0005] An alternative method of coining has been used to form sheet metal without the need for a full set of two dies. Instead, a single rigid die is positioned on one side of the sheet of material. Force is then applied to the other side of the material, either by using a backing material or by fluid pressure, thereby forming the material into the desired configuration determined by the single die. Although advances have been made over the years in sheet metal forming technology using one or two dies, the expense of engineering, manufacturing, and maintaining any die has hindered the low-volume production of metal parts. In addition to the manufacturing cost of the die(s), the time to produce the die(s) further hinders the use of low-volume and prototypes.

[0006] Another technique for forming sheet metal is called incremental sheet forming (ISF), in which only a small portion of the sheet metal is actually incrementally configured at any one time by forming. Emmens et al., “Incremental Sheet Forming Technology—A Brief Historical Review,” Journal of Materials Processing Technology (2010) and Jeswiet et al., “Asymmetric Single-Point Incremental Forming of Sheets,” CIRP Annals—Manufacturing Technology 54(2): 88-114 (December 2005).

[0007] The incremental sheet metal forming system of the present invention not only provides flexibility over existing systems by eliminating the long lead times and need for producing and using expensive dies to form complex sheet metal parts, but also localizes the forming forces on the workpiece so as to precisely and locally control the stresses that occur during sheet metal forming.

[0008] Description of Related Applications

[0009] Single point incremental forming (SPIF), a variation of ISF, is a method for single-sided forming of sheet metal (usually metal) without the need for any die. Previous SPIF examples have embodied many different implementations. One of the simplest implementations of SPIF includes a rigid clamping mechanism for restraining a sheet metal workpiece along all four outer edges of the sheet metal workpiece while a single forming tool or roller punch is located on one side of the sheet metal. Following a specified trajectory, the tool is pressed against the clamped sheet metal to form the desired shape. Emmens et al., Section 2.2 and Figure 4 above, with reference to Iseki et al., "Flexible and Incremental Sheet Metal Forming Using Spherical Rollers"; Proceedings of the 40th JJCYP Conference (1989, pp. 41-44).

[0010] Two-point incremental forming (TPIF), also known as double-sided incremental forming, is another variation of ISF in which the sheet is typically clamped at its outer edges and forces are applied from each side of the sheet. An example of a double-sided forming method uses two opposing rigid forming tools that move along either side of the workpiece to apply and counteract forces. In U.S. Pat. No. 8,302,442, a sheet fixture assembly 20 (clamp assembly) supports a workpiece 12 while forming tools 32 and 32" apply a double-sided force to the workpiece 12. The tools can be positioned directly relative to each other or offset relative to each other. In addition, each forming tool can be mounted on a 6-axis platform, allowing movement in 3 translation directions and 3 rotational axes. (See also U.S. Pat. Nos. 8,783,078; 8,773,143 and 8,322,176). Although better control is exerted on the workpiece than SPIF technology to some extent, it requires a reduction in forming speed and an additional level of complexity and accuracy to coordinate the path of each relative forming tool through the controller 26 and form the workpiece 12 into the desired configuration. However, it is still difficult to accurately control the relative tool positioning during the forming process, resulting in defects in the resulting workpiece configuration, such as wrinkles and tears.

[0011] In another example of double-sided forming, a rigid tool is located on one side of the workpiece, and instead of a second rigid tool side on the other side, a single die is located on the other side. As seen in Japanese Patent 10-314855 (Ueno et al.), the die 3 is fixed in place, and the tool 5 presses the workpiece 4 against the die 3. While the tool 5 is relatively universal in this example, the die 3 must be specifically manufactured for each different desired configuration, thus retaining the challenges associated with the manufacturing lead time and cost of using any die.

[0012] A further example of a double-sided forming method is shown in U.S. Pat. No. 7,536,892. A clamp fixture 1 is arranged to clamp the circumference of a workpiece W. A die 2 and a tool 4 are sequentially advanced toward each other to press the workpiece W into a shape corresponding to the die 2. However, the presence of the die 2 retains the disadvantageous long lead times and costs inherent in the use of any die.

[0013] Another example of a double-sided forming method is shown in U.S. Patent No. 6,151,938. A press 2 including a plurality of punching elements is located on one side of a blank 3, while an elastomer 4 is positioned on the other side and in contact with the blank 3 surface. The control unit 5 moves the punching element toward its intended position along only one axis, thereby applying force to the blank 3. The elastomer 4 generates a repulsive force that supports the blank 3. In the case of a long formed product, the blank 3 can be moved longitudinally, thereby gradually performing the forming process along the length of the blank. Since many punching parts are used to form the blank, the process is also mechanically complex. This stamping process is also limited to producing relatively simple shapes.

[0014] In another example, U.S. Pat. No. 3,342,051 describes a rotary double-sided ISF apparatus and method in which a blank 6 is completely secured between two clamping rings 3 and 4, which are free to slide on guide pins 5 in the direction of an axis perpendicular to the plane of the blank 6. In turn, the guide pins 5 are attached to a backing plate 1 that rotates with a turntable V (not shown). A deforming tool 7 or rotating ball 8 is positioned on one side of the blank 6, and an elastic material 2 is positioned on the other side and attached to the backing material 1. As the blank 6 rotates with the elastic material 2 and the turntable V, the deforming tool 7 is fed laterally along an axis, traversing from the outer edge of the blank 6 to its center in a spiral rotation. The deforming tool 7 is brought against the blank 6 along an axis perpendicular to the plane of the blank 6 so as to deform the blank 6 into a desired configuration that always has a circular cross-section. Since the deforming tool 7 and the turntable V move only in two linear axes and one rotational axis, respectively, this forming method is disadvantageously limited to producing "rotating figures" that only contain circular cross-sectional shapes. Thus, the '051 device can neither move linearly independently in three axes (ie, X, Y, and Z axes) nor form asymmetric shapes, which are achievable with the present invention.

[0015] In contrast, the present invention is preferably directed to a double-sided incremental sheet forming apparatus and method that does not utilize a purpose-built die, but rather has unique tooling and movement that is universally applicable to form a variety of shapes with a minimal amount of force.

[0016] The present invention preferably includes a primary rigid tool and a secondary tool having layers of compressible and elastic materials. A workpiece consisting of a sheet is positioned between opposing tools. The primary rigid tool applies a force to one surface of the sheet, while the secondary elastic tool applies a controlled opposing force to the opposing surface of the sheet. This double-sided process localizes the forces on the sheet in the contact area on the workpiece between the opposing tools (rather than the widely applied forces and resulting total stresses applied to the entire sheet when only a rigid tool is used on one side of the sheet). By localizing the forces on the sheet to the contact area, the stresses and the resulting formation are also localized and more accurately and precisely controlled according to the present invention when compared to single-point incremental sheet forming.

[0017] Furthermore, by utilizing a primary rigid tool positioned on one side of the workpiece in conjunction with an opposing secondary elastic tool, both having linear independent motion (rather than using two opposing rigid tools found in many previous double-sided techniques), the present invention avoids potential wrinkling and tearing of the resulting workpiece. Thus, the unique double-sided forming process and apparatus of the present invention produces many asymmetrical and more accurately formed products through a simpler and better controlled process, and ultimately using less power than single-sided or other double-sided incremental sheet forming methods. Summary of the invention

[0018] According to one aspect of the invention, a device for incrementally forming a workpiece is described (see, e.g. Figures 1A to 1C , FIG. 2A to FIG. 2C , FIG. 3A to FIG. 3C , FIG. 4A to FIG. 4B and Figure 5 ). The workpiece has first and second opposing and parallel surfaces, a working area for forming the workpiece, and defines a reference plane parallel to the surfaces. The apparatus includes a primary forming tool assembly positioned adjacent to and facing the first surface of the workpiece and capable of moving into and out of engagement with the workpiece in a direction perpendicular to the reference plane and in all directions parallel to the reference plane. The primary forming tool assembly may have a forming tip for forming the workpiece. The tip is positioned facing the first surface of the workpiece. The apparatus also includes a secondary forming tool assembly having a resilient surface portion or material layer facing the second surface of the workpiece and capable of moving into and out of engagement with the workpiece in a direction perpendicular to the reference plane.

[0019] One or both of the workpiece and the primary forming tool assembly are movable relative to each other to position the primary forming tool assembly within a work area; and a force is applied to a first surface of the workpiece in a direction perpendicular to a reference plane, while a resilient secondary forming tool assembly engages the workpiece and applies a counter force to support a second surface of the workpiece so that a localized force is applied to the workpiece during forming.

[0020] According to one aspect of the present invention, the above-mentioned device may further include a sheet feeding assembly (see, for example, Figures 1A to 1C ). The sheet feeding assembly includes a sheet feeding roller assembly having at least one roller set contacting the respective first and second surfaces of the workpiece. The roller set is capable of moving the workpiece in a direction parallel to the reference plane.

[0021] Alternatively, the sheet feed assembly comprises a sheet feed belt assembly having at least one continuous belt surrounding and contacting a set of rotatable rollers (see, e.g. FIG. 2A to FIG. 2C ). The belt is positioned in contacting relationship with the first surface or the second surface of the workpiece and is capable of moving the workpiece in a direction parallel to the reference plane.

[0022] Alternatively, the sheet feed assembly may include a sheet fixture assembly having a rigid frame and a holder capable of securely holding the workpiece therebetween (see, e.g., FIG. 3A to FIG. 3C , Figure 4A To Figure 4C and Figure 5 The sheet fixture assembly defines an opening for accessing the workpiece through a primary forming tool assembly on a first surface of the workpiece and through a secondary forming tool assembly on a second surface of the workpiece.

[0023] According to another aspect of the invention, an apparatus for forming a workpiece of sheet material is described. The workpiece has first and second opposing and parallel surfaces and defines a reference plane parallel to the first and second surfaces of the workpiece. The apparatus includes a sheet feed assembly capable of moving the workpiece in a direction parallel to the reference plane. The apparatus also includes a main forming tool assembly positioned facing the first surface of the workpiece and capable of moving in a first direction perpendicular to the reference plane and in a second direction parallel to both the reference plane and the direction of movement of the workpiece of the sheet feed assembly.

[0024] The apparatus further comprises a backing roller tool assembly which is movable in a direction perpendicular to the reference plane and has an elongated cylindrical configuration for rotation about its longitudinal axis, the longitudinal axis being positioned parallel to the second direction of movement of the main forming tool assembly. The backing roller tool is comprised of an inner core and an outer elastic layer fixed thereto, the outer elastic layer being positioned facing the second surface of the workpiece. Alternatively, the backing roller tool assembly may have an outer surface, a portion of which is compressible when a force is applied thereto and a portion of which elastically returns to its non-compressed configuration when the force is removed (see, e.g. Figures 1A to 1C , FIG. 2A to FIG. 2C and FIG. 3A to FIG. 3C ).

[0025] The main forming tool assembly and the backing roller tool assembly are capable of simultaneously contacting corresponding first and second opposing surfaces of a workpiece that are generally opposite to each other, with the main forming tool assembly applying a force on the first surface of the workpiece to form the workpiece, and the backing roller tool assembly applying an opposing force on the second surface of the workpiece when the workpiece is formed, through which the process generates a local force on the workpiece.

[0026] According to another aspect of the invention, an apparatus for forming a sheet workpiece into a predetermined configuration is described. The workpiece has first and second opposing and parallel surfaces and defines a reference plane parallel to the workpiece surfaces. The apparatus includes a backing roller tool assembly that is rotatable about its longitudinal axis and has an inner core and an outer elastic layer or outer surface portion secured thereto. The backing roller assembly faces the second surface of the workpiece along its longitudinal axis and is parallel to the reference plane (see, e.g., Figures 1A to 1C , FIG. 2A to FIG. 2C and FIG. 3A to FIG. 3C ).

[0027] The apparatus also includes a primary forming tool assembly positioned adjacent to and facing a first surface of the workpiece. The primary forming tool assembly is capable of applying a force on the first surface of the workpiece to partially form the workpiece while moving in a first direction parallel to the longitudinal axis of the backing roller assembly. The apparatus also includes a sheet fixture assembly having a rigid frame and a retainer capable of securely retaining the workpiece therein. The sheet fixture assembly is positioned parallel to the reference plane and defines an opening for accessing the workpiece through the primary forming tool assembly on the first surface of the workpiece and through the secondary forming tool assembly on the second surface of the workpiece.

[0028] The primary forming tool assembly and the backing roller tool assembly are movable in a direction perpendicular to the reference plane so as to contact respective first and second surfaces of the workpiece. As a result, a force applied by the primary forming tool assembly on the first surface of the workpiece is counteracted by a counteracting force applied by the backing roller tool assembly on the second surface of the workpiece, thereby supporting the workpiece in a localized area of ​​the primary forming tool while the workpiece is being formed.

[0029] According to another aspect of the invention, another apparatus for incrementally forming a workpiece is described (see, e.g. Figures 1A to 1C , FIG. 2A to FIG. 2C , FIG. 3A to FIG. 3C , FIG. 4A to FIG. 4B and Figure 5 ). The workpiece has first and second opposing surfaces positioned on an XY plane of an "X", "Y", "Z" three-dimensional coordinate system. The apparatus includes a primary forming tool assembly positioned adjacent to and facing the first surface of the workpiece. The apparatus also includes a secondary forming tool assembly having a rigid body and a layer of compressible and elastic material fixed thereto, and the layer of material is positioned adjacent to and facing the second surface of the workpiece.

[0030] The workpiece, the primary forming tool assembly, and the secondary forming tool assembly are capable of independent movement relative to each other in a predetermined order and pattern along at least one of the X, Y, or Z axes of the coordinate system. The primary forming tool assembly and the workpiece are also capable of movement relative to each other along the X, Y, and Z axes. The secondary forming tool assembly is capable of movement relative to the workpiece along the Z axis. As a result, the primary forming tool assembly is capable of exerting a force on a first surface of the workpiece. The secondary forming tool assembly is also capable of exerting a counterforce against a second surface of the workpiece along the Z axis, thereby locally supporting the workpiece. During the forming process, the forming force is substantially localized at the area of ​​contact between the primary forming tool and the workpiece (see, e.g., Fig.10 ).

[0031] According to another aspect of the invention, the apparatus includes a control system capable of simultaneously coordinating the respective movements of the workpiece, the primary forming tool assembly, and the secondary forming tool assembly relative to each other. The coordinated movements of these components cause the primary forming tool assembly to follow a predetermined path along a first surface of the workpiece while the secondary forming tool assembly simultaneously follows the same path along a second surface of the workpiece.

[0032] In another aspect of the invention, a method for incrementally forming a workpiece having at least one working region and having first and second opposing and parallel surfaces located in an XY plane of an "X", "Y", "Z" three-dimensional orthogonal coordinate system is described. (See, e.g. Figure 7 ) The method includes providing an apparatus having a main forming tool assembly positioned adjacent to and facing a first surface of a workpiece; and a backing forming tool assembly having a compressible and resilient surface portion positioned adjacent to and facing a second surface of the workpiece. The workpiece, the main forming tool assembly, and the backing forming tool assembly are independently movable relative to each other in a predetermined sequence and pattern.

[0033] The primary forming tool assembly is positioned relative to the workpiece to simultaneously move to predetermined X, Y, and Z coordinates so as to be adjacent to a first surface of the workpiece within a working area. The backing forming tool assembly is positioned relative to the workpiece to simultaneously move to a predetermined Z coordinate within the working area so as to contact a second surface of the workpiece and opposite the position of the primary forming tool assembly. The primary forming tool assembly is advanced toward the workpiece in a Z direction to a predetermined Z coordinate so as to contact the first surface of the workpiece at a contact point within the working area and exert a force thereon. As a result, the workpiece is formed into a predetermined configuration, and the resilient backing forming tool assembly is compressed to support the second surface of the workpiece while being formed.

[0034] The primary forming tool assembly moves relative to the workpiece in an XY plane along a set of predetermined coordinates (see, e.g. Figure 7 ), thereby following a predetermined path along which the workpiece is uniformly formed in the Z direction within the work area. The primary forming tool assembly is retracted from the workpiece in the Z direction and repositioned in the XY plane to a set of predetermined coordinates adjacent to the first surface of the workpiece. The above steps may be repeated by sequentially utilizing incremental values ​​of the Z coordinate until the workpiece is fully formed within the work area.

[0035] In another aspect of the invention, the apparatus of the above method further includes a control system having a controller assembly and a non-contact or contact sensor. Using the sensor(s), the controller assembly simultaneously measures the amount of forming of the workpiece at a specific location along its forming path. The generated measurement results are compared with the predetermined amount of forming of the workpiece at the same specified location along the forming path. The generated comparative measurement results are relayed to the controller assembly. The controller assembly then adjusts the position of at least one of the main forming tool assembly and the backing forming tool assembly relative to the pre-programmed amount of desired forming along the path so as to form the workpiece into a predetermined shape.

[0036] Another aspect of the present invention relates to a method for incrementally forming a workpiece having at least a first working area and a second working area separated from each other and having first and second opposite and parallel surfaces located on an XY plane of an "X", "Y", "Z" three-dimensional orthogonal coordinate system (see, e.g. FIG. 8A to FIG. 8B The method includes providing an apparatus having a main forming tool assembly positioned adjacent to and facing a first surface of a workpiece, and a backing forming tool assembly having a compressible and resilient surface portion and positioned adjacent to and facing a second surface of the workpiece. The workpiece, the main forming tool assembly, and the backing forming tool assembly are independently movable relative to each other in a predetermined sequence and pattern.

[0037] The primary forming tool assembly is positioned relative to the workpiece to simultaneously move to predetermined X, Y, and Z coordinates so as to be adjacent to a first surface of the workpiece in a first working area. The resilient backing forming tool assembly is positioned relative to the workpiece at a predetermined Z coordinate within the first working area so as to contact a second surface of the workpiece and opposite the position of the primary forming tool assembly. The primary forming tool assembly is advanced toward the workpiece in a Z direction to a predetermined Z coordinate so as to contact and exert a force on the first surface of the workpiece within the first working area at a contact point.

[0038] As a result, the workpiece is formed into a predetermined configuration, and the resilient surface portion of the backing forming tool assembly is compressed to support the second surface of the workpiece, causing it to be localized on the workpiece when forming. The main forming tool assembly is moved relative to the workpiece in the XY plane along a set of predetermined coordinates having substantially the same Z coordinate, thereby following a predetermined path along which the workpiece is uniformly formed in the Z direction in the first working area. The main forming tool assembly is retracted from the workpiece in the Z direction and repositioned in the XY plane at a set of predetermined coordinates in the second working area adjacent to the first surface of the workpiece.

[0039] The primary forming tool assembly is advanced in the Z direction toward the workpiece in the second working area to a Z coordinate that is the same as the Z coordinate selected for the first working area so as to contact the first surface of the workpiece at the contact point and exert a localized force thereon. As a result, the workpiece is formed into a predetermined configuration, and the resilient surface portion of the secondary forming tool assembly is compressed to support the second surface of the workpiece as the workpiece is formed. The primary forming tool assembly is moved relative to the workpiece in the XY plane along a set of predetermined coordinates that are substantially the same in the Z direction, thereby following a predetermined path along which the workpiece is uniformly formed in the Z direction in the second working area. The primary forming tool assembly is retracted from the workpiece in the Z direction. The above steps may be repeated by sequentially utilizing an incremental value of the Z coordinate until the workpiece is fully formed in each working area.

[0040] According to another aspect of the invention, a method for incrementally forming at least one working region of a workpiece is described, the workpiece initially having a generally flat configuration and first and second opposing surfaces positioned in an XY plane of an "X", "Y", "Z" three-dimensional orthogonal coordinate system (see, e.g. Figure 7 and FIG. 8). According to the method, a primary forming tool assembly is positioned adjacent to a first surface of a workpiece. The primary forming tool assembly has a tip capable of forming the workpiece when positively engaged with the workpiece, the tip having a hardness value greater than a hardness value of the workpiece.

[0041] The backing roller tool assembly is positioned adjacent to the second surface of the workpiece. The backing roller tool assembly is movable in the Z direction. The backing roller tool assembly further has a compressible and resilient outer surface portion, and at least one of the backing roller tool assembly and the outer resilient surface portion is rotatable about a longitudinal axis extending through the center of the backing roller tool assembly. The backing roller tool assembly is advanced toward the workpiece along the Z axis to contact and support the second surface of the workpiece.

[0042] The primary forming tool assembly is advanced relative to the workpiece along the Z axis for engaging the tip with the first surface of the workpiece and providing a predetermined amount of forming force thereon to form the workpiece. The position of the backing roller tool assembly is maintained to provide sufficient reaction force on the second surface of the workpiece. The sufficiency of the reaction force is determined by the compressibility and elasticity of the outer surface portion of the backing roller tool assembly.

[0043] The primary forming tool assembly is moved relative to the workpiece in the XY plane along a set of predetermined coordinates having substantially identical Z coordinates so as to follow a predetermined path along which the workpiece is uniformly formed in the Z direction. The backing roller tool assembly is continuously moved in tandem with the movement of the primary forming tool assembly to remain substantially opposed to the tip of the primary forming tool assembly with the workpiece therebetween, thereby maintaining a local force on the workpiece. The primary forming tool assembly and the backing roller tool assembly are retracted from the workpiece. The above steps may be continuously repeated in one or more additional working areas of the workpiece until the workpiece is formed to a pre-programmed and predetermined final configuration. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figures 1A to 1C A first embodiment (Embodiment 1) of the present ISF system is depicted, having a sheet feed roller assembly for advancing a workpiece, a primary forming tool assembly, and a secondary forming tool assembly. In particular:

[0045] Figure 1A depicts an exemplary axonometric view of Embodiment 1;

[0046] Figure 1B depicts an exemplary front cross-sectional view of Embodiment 1; and

[0047] Figure 1C An exemplary side cross-sectional view of Example 1 is depicted.

[0048] FIG. 2A to FIG. 2C A second embodiment (Embodiment 2) of the present ISF system is depicted, having a sheet feed belt assembly for advancing a workpiece, a primary forming tool assembly, and a secondary forming tool assembly. In particular:

[0049] Figure 2A depicts an exemplary axonometric view of Embodiment 2;

[0050] Figure 2Bdepicts an exemplary front cross-sectional view of Embodiment 2; and

[0051] Figure 2C An exemplary side cross-sectional view of Example 2 is depicted.

[0052] FIG. 3A to FIG. 3C A third embodiment (Embodiment 3) of the present ISF system is depicted, having a movable frame assembly for advancing a workpiece, a primary forming tool assembly, and a secondary forming tool assembly. In particular:

[0053] Figure 3A depicts an exemplary axonometric view of Embodiment 3;

[0054] Figure 3B depicts an exemplary front cross-sectional view of Embodiment 3; and

[0055] Figure 3C An exemplary side cross-sectional view of Example 3 is depicted.

[0056] Figure 4A and Figure 4B A fourth embodiment (Embodiment 4) of the present ISF system is depicted, the system having a fixed frame assembly for holding a workpiece, a primary forming tool assembly, and a secondary forming tool assembly. In particular:

[0057] Figure 4A depicts an exemplary axonometric view of Embodiment 4; and

[0058] Figure 4B An exemplary front cross-sectional view of Example 4 is depicted.

[0059] Figure 5 Another exemplary isometric view of Embodiment 4 incorporated into a machine center is depicted.

[0060] FIG. 6A to FIG. 6D Depicted is an exemplary front cross-sectional view of a workpiece undergoing a series of incremental forming steps in accordance with an embodiment of the present invention.

[0061] Figure 7 is an exemplary top view of a workpiece formed according to an embodiment of the present invention.

[0062] Fig. 8A and Figure 8B A method for forming multiple formed regions in a single workpiece undergoing a series of incremental forming steps according to an embodiment of the present invention is described. In particular:

[0063] Fig. 8A is an exemplary top view of a workpiece formed in multiple positions according to an embodiment of the present invention; and

[0064] Figure 8BDescribed are embodiments according to the present invention, and in particular Fig. 8A Depicted is an exemplary front cross-sectional view of a workpiece undergoing a series of incremental multiple forming steps.

[0065] 9A to 9C Depicted are cross-sectional views of various primary forming tools contemplated for use in practicing the present invention. In particular:

[0066] Fig.9A A master forming tool made from a single component is depicted;

[0067] Fig. 9B depicts a primary forming tool made of a separate shaft and tip; and

[0068] Fig. 9C Depicted is the main forming tool made of separate shaft, tip and bearing.

[0069] Fig.10 A partial cross-sectional view of the above-described embodiment of the present invention is depicted along with a diagram of a synchronous control system. DETAILED DESCRIPTION

[0070] The present invention relates to a unique double-sided incremental sheet forming apparatus and method that does not use a specially made die, but rather has universally applicable tooling to form a variety of shapes with a minimum amount of force.

[0071] By way of illustration only, the present invention is applicable to the forming of parts and components from sheet materials for all major industries, such as automotive, aerospace, industrial, architecture, engineering, construction and consumer products.

[0072] Figure 1A , Figure 1B and Figure 1C A first embodiment (Embodiment 1) of an incremental sheet forming (ISF) system of the present invention is depicted. The system includes a sheet feed roller assembly 40 for accurately advancing a workpiece 80, a primary forming tool assembly 10, and a secondary forming tool assembly (eg, backing roller tool assembly 20).

[0073] exist Figure 1A 8, a workpiece 80 is shown formed into its final shape 81. The workpiece 80 comprises a sheet of material (e.g., sheet metal) that may be made of steel, aluminum, plastic, or another formable material. The sheet of material typically begins in a flat state that is shown in Example 1 as being parallel to a reference plane. The reference plane is depicted as XY plane 82 and is defined by the initial configuration of the workpiece 80 prior to incrementally forming the workpiece. The sheet may also be pre-formed with certain preliminary features prior to performing additional operations in accordance with the present invention.

[0074] The sheet feed roller assembly 40 includes one or more synchronized roller sets 42 (42A-42H) positioned to contact the workpiece 80. The synchronized rollers 42 typically contact each opposing surface of the workpiece 80 along first and second edges (or boundary edge portions) 88 or 89. However, other engaging surface portions are contemplated.

[0075] The sheet feed roller assembly 40 preferably advances the workpiece 80 back and forth along an axis extending between Figure 1A The Y axis is shown in Figure 1. In Embodiment 1, the sheet feed roller assembly 40 includes four synchronized roller sets 42. Two roller sets (42A-42B and 42C-42D) are positioned along the first edge 88 of the workpiece 80, and two roller sets (42E-42F and 42G-42H) are positioned along the second edge 89 of the workpiece. The first set of these rollers is positioned to contact the surface of the workpiece 80, and the second set of these rollers is positioned to contact the opposite surface of the workpiece 80.

[0076] like Figure 1A As shown, opposing pairs of rollers (e.g., 42A and 42B with 42C and 42D; 42E and 42F with 42G (not shown) and 42H) are preferably positioned directly opposite each other to contact opposing surfaces of the workpiece 80. These rollers preferably contact and clamp the opposing surfaces of the workpiece 80 along edges 88 or 89 to drive the workpiece along the Y axis.

[0077] At least one of the rollers (42A-42D) on the first edge 88 and at least one of the rollers (42E-42H) on the second edge 88 are engaged with motor(s), control systems and software (not shown) to coordinate and synchronize the rotation of the rollers. As a result, the rollers move the workpiece 80 precisely to a desired position, preferably along a translation axis (Y axis). See also FIG. 6A to FIG. 6D Motor actuation instructions, where Figures 1A to 1C The same motor control system can be used in

[0078] The synchronous roller 42 preferably includes a base core made of steel, aluminum or another suitable material, and may additionally have a coating or layer of polyurethane, neoprene, rubber or another suitable material that is sufficiently flexible and resilient at its circumference to enhance the positive clamping force of the workpiece 80.

[0079] exist Figures 1A to 1CIn the embodiment, the primary forming tool assembly 10 is positioned adjacent to one surface of the workpiece 80 to engage the first (i.e., upper) surface of the workpiece and moves in a direction transverse to the movement of the workpiece, such as along the X-axis shown in Example 1. Thus, such movement of the primary forming tool assembly 10 is perpendicular to the direction in which the workpiece 80 moves (along the Y-axis) when driven by the sheet feed roller assembly 40. The primary forming tool assembly 10 also moves in a direction perpendicular to an XY reference plane 82 of the workpiece 80, which is shown as the Z-axis in Example 1, so as to be able to move into and out of contact with the first (i.e., upper) surface of the workpiece.

[0080] The secondary forming tool assembly includes a backing roller tool assembly 20, which preferably has a solid core 21 and has an outer layer 22 of flexible, compressible or elastic material (or surface portion of the backing roller tool) fixed to the circumference of the core 21 to provide a flexible, compressible, elastic and controlled counteracting force on the second or lower surface of the workpiece 80 when the primary forming tool assembly 10 engages the opposite (i.e., first or upper) surface of the workpiece.

[0081] In Example 1 (see e.g. Figure 1A , Figure 1B and Figure 1C ), the backing roller tool assembly 20 is positioned adjacent to and facing a surface of the workpiece 80 that is opposite to the surface of the main forming tool assembly 10. Thus, the workpiece 80 separates the backing roller tool assembly 20 from the main forming tool assembly 10. The backing roller tool assembly 20 is elongated cylindrical and has a longitudinal axis of rotation extending longitudinally therethrough that is positioned along the X-axis parallel to the direction of movement of the main forming tool assembly 10, and contacts the opposite (i.e., lower) surface of the workpiece 80.

[0082] The tip of the primary forming tool assembly 10 and the longitudinal axis of the backing roller tool assembly 20 are preferably positioned directly opposite each other so as to face each other along the X-axis on either side of the workpiece 80. Preferably, the length of the backing roller tool assembly 20 is about at least substantially equal to or longer than the distance the primary forming assembly tool 10 is permitted to travel along the X-axis. As a result, the backing roller tool assembly 20 remains in formable and direct contact with the second (i.e., lower) surface of the workpiece 80 as the primary forming tool assembly 10 engages the first (i.e., upper) surface of the workpiece and moves along the X-axis.

[0083] exist Figure 1A , Figure 2A and Figure 3A middle, onlyFor purposes of illustration, the backing roller tool assembly 20 is shown as being positioned away from and not in direct contact with the workpiece 80. During operation of the apparatus of the present invention, the resilient layer 22 of the backing roller tool assembly 20 is actually positioned facing toward and in direct engagement with the second (i.e., lower) surface of the workpiece 80. When the primary forming tool assembly 10 engages the first or opposing surface of the workpiece 80 and exerts a force thereon, the result is the generation of a localized force in the area where the primary forming tool assembly 10 contacts the workpiece 80.

[0084] The main forming tool assembly 10 and the resilient layer 22 of the backing roll tool assembly 20 are actually positioned to provide opposing forces to each other at their contact points along the X-axis, with the workpiece 80 positioned therebetween. More specifically, the main forming tool assembly 10 and the resilient layer 22 are in indirect contact through the forming workpiece 80 due to the force applied to the first (i.e., upper) surface of the workpiece by the main forming tool assembly 10 and the opposing force applied to the opposite or second (i.e., lower) surface of the workpiece by the flexibility of the backing tool roll assembly 20 and the controlled compression of the resilient layer 22. The amount of the opposing force is controlled by the hardness, thickness, and resulting compressibility and elasticity of the resilient layer 22 (or outer surface portion) of the backing roll tool assembly 20.

[0085] In addition to rotating about its longitudinal axis, the backing roller tool assembly 20 also moves in a direction perpendicular to the XY reference plane 82 of the workpiece 80, which is shown as the Z axis in Embodiment 1. Movement along the Z axis allows the backing roller tool assembly 20 to maintain contact with the workpiece 80 while the primary forming tool assembly 10 applies a precisely controlled opposing force on the workpiece.

[0086] More specifically, if Figure 1B and Figure 1C As shown, the backing roller tool assembly 20 including the elastic layer 22 is positioned along its longitudinal axis on the X-axis to contact the lower surface (i.e., the second surface) of the workpiece 80, thereby causing a continuous narrow zone of contact points to be formed along the X-axis. More specifically, the contact zone occurs where the circumference of the elastic layer 22 intersects the lower surface of the workpiece 80. In other words, when the elastic layer 22 and the lower surface of the workpiece 80 contact each other, a narrow contact area or contact zone is generated between them. This zone occurs at the tangent line of the circumference of the elastic layer 22 and the lower surface of the workpiece. At the same time, the main forming tool assembly 10 is positioned along the X-axis, facing the upper surface of the workpiece, and opposite to the contact zone of the elastic layer 22 and the lower surface of the workpiece 80.

[0087] When the primary forming tool assembly 10 is pressed against the first surface of the workpiece 80, it exerts a force on the workpiece at a given contact area along the X-axis. The workpiece 80 in turn exerts a force on the elastic layer 22 at a forced application area along a narrow contact zone (which is along the X-axis). As a result, the elastic layer 22 is compressed and exerts a counteracting force at a relatively localized area of ​​the narrow contact zone in contact with the workpiece 80 along the X-axis. As both the primary forming tool 10 and the elastic layer 22 exert forces on opposite sides of the workpiece 80, the force is substantially concentrated at the contact area between the primary forming tool 10 and the workpiece 80. At this contact area or "tangent zone", due to the cylindrical shape of the elastic layer 22, the force exerted by the workpiece 80 on the elastic layer 22 is advantageously kept concentrated and localized, thereby avoiding the resulting workpiece warping and tearing. As a result, the apparatus of Example 1 is capable of producing a number of complex and asymmetric configurations on the workpiece 80 at any given time during operation, as desired by the selected control system (see, e.g. Fig.10 ).

[0088] In addition, the backing roller tool assembly 20 has a cylindrical configuration for rotation on its longitudinal axis. The backing roller tool assembly 20 advantageously allows for accurate and rapid positioning of the workpiece 80 when it is positioned perpendicularly (i.e., the X-axis) to the direction of movement of the workpiece (i.e., the Y-axis). The cylindrical configuration of the backing roller tool assembly 20 also advantageously allows for a simpler and more compact design of the device itself compared to many previous ISF devices.

[0089] In Example 1, the core 21 is a solid rod. The outer elastic layer 22 of the backing roller tool assembly 20 is fixed thereto and rotates freely together around their longitudinal axis. The elastic layer 22 can be fixed by rigidly attaching or fixedly attaching to the core 21, or alternatively fixed by circumferentially surrounding the core, but can rotate freely around the core. For example, the elastic layer 22 can be made of multiple materials or layers so that it can rotate freely by a bearing assembly (e.g., a sliding bearing) positioned around the core 21 as known in the art. In another embodiment, the core 21 can be a hollow tube or cylinder that rotates freely around the bearing assembly with the elastic layer 22. In another alternative embodiment, the core 21 can be fixed (i.e., non-rotatable), while the elastic layer 22 can rotate freely around it. In an alternative embodiment, the rotation of the backing roller tool assembly 20 can be controlled by mechanical or electromechanical equipment known in the art. In further aspects, the backing roll tool assembly 20 includes the compressible and resilient layer 22, and at least one of the backing roll tool assembly and the outer resilient surface portion is rotatable about an axis extending through a center of the backing roll tool assembly.

[0090] Preferably, the longitudinal axis of the backing roller tool assembly 20 is movably positioned so that the resilient layer 22 can maintain continuous contact with the surface of the workpiece 80 along the X-axis. When the workpiece is moved along the Y-axis by the sheet feed roller assembly 40, contact with the workpiece 80 also causes the backing roller tool assembly 20 to rotate by engaging with the workpiece 80.

[0091] The rigid core 21 may preferably be constructed of steel, aluminum or another suitable material. The core 21 may be solid or hollow, depending on size and configuration.

[0092] The elastic layer 22 is preferably made of a resiliently formable material having compressive strength so that the material can be formed under the force applied by the main forming tool assembly 10 to the workpiece 80. The material selected for the elastic layer 22 is also capable of substantially returning to its original or non-compressed shape when the force applied to the workpiece 80 from the main forming tool assembly 10 is removed. For example, the elastic layer 22 can be made of an elastomer, preferably polyurethane. Alternatively, it can also be made of rubber, neoprene, nitrile or another suitable material that can accurately, predictably, and controllably deform and be resilient when in contact with the workpiece 80.

[0093] The durometer range of the elastic layer 22 is generally about Shore 10A to about 80D, preferably about 30A to about 95A. Depending on the hardness of the selected material, the thickness of the elastic layer 22 can vary between about 0.01 mm and about 25 mm, preferably about 1.0 mm to about 5.0 mm. By selecting a preferred durometer for the elastic layer 22, when the main forming tool assembly 10 applies a force on the first surface of the workpiece, a precise and controlled opposing force can be applied to the second surface of the workpiece 80.

[0094] During the forming process, the sheet feed roller assembly 40 is operable to move the workpiece 80 back and forth along the Y axis to its desired position. The main forming tool assembly 10 is simultaneously movable along the X axis to a desired position. The backing roller tool assembly 20 is simultaneously movable along the Z axis to a desired position in contact with the surface of the workpiece 80. When in contact with the workpiece 80, the backing roller tool assembly 20 is preferably free to rotate along its longitudinal axis by frictional engagement with the workpiece as the sheet feed roller assembly 40 moves the workpiece along the Y axis to its desired position.

[0095] The sheet feed roller assembly 40, the main forming tool assembly 10 and the backing roller tool assembly 20 may be controlled by different systems (e.g., mechanical, hydraulic) that may interface directly or indirectly with each other and with a computing entity to send and receive information regarding their precise positioning at their desired locations. FIG. 6A to FIG. 6D and FIG. 9 for the motor actuation description and Fig.10 control systems, where similar motors, control systems and software can be used Figures 1A to 1C In the arrangement.

[0096] When the workpiece 80, the primary forming tool assembly 10, and the backing roller tool assembly 20 are independently moved to their designated and coordinated positions, the primary forming tool assembly 10 can abut the workpiece 80 by moving along a Z axis perpendicular to the workpiece's original XY reference plane 82. At the same time, the backing roller tool assembly 20 can move along the Z axis so as to be in deformable and resilient contact with the workpiece 80 along its longitudinal axis (i.e., along the X axis).

[0097] By applying force to the workpiece 80 by the primary forming tool assembly 10, the workpiece begins to be locally formed into its desired configuration at the precise contact point where the force is applied. More specifically, as the primary forming tool assembly 10 traverses along its predetermined path relative to the workpiece 80, local forces are generated at the contact areas in the X, Y, and Z directions. As the primary forming tool assembly 10 moves relative to the workpiece 80, the workpiece is continuously formed along force vectors having predetermined magnitudes and components in the X, Y, and Z directions. The local forces plastically and permanently form the workpiece 80 into the desired shape at the areas of contact with the workpiece where the force is applied.

[0098] When the primary forming tool assembly 10 applies a force on one surface of the workpiece 80, the backing roller tool assembly 20 maintains continuous contact with the opposing surface of the workpiece. Due to the force applied by the primary forming tool assembly 10 on the workpiece 80, the resilient layer 22 deforms to generate a reaction force capable of supporting the workpiece as it is formed into its desired shape.

[0099] As the primary forming tool assembly 10 advances along the Z axis and partially forms the workpiece 80 into a desired configuration, the backing roller tool assembly 20 retreats along the Z axis to the extent required to adjust the movement of the advancing primary forming tool assembly 10. Preferably, the resilient layer 22 remains deformed while moving in precisely controlled contact with the workpiece 80 and generates a counter force that supports the workpiece as the backing roller tool assembly moves along the Z axis. Due to its resilient properties, the resilient layer 22 is selected to be able to substantially return to its original configuration once the primary forming tool assembly 10 retreats along the Z axis and the sheet feed roller assembly 40 moves the workpiece 80 to a new position along the Y axis.

[0100] Once the workpiece 80 is partially formed to its desired configuration at the selected location, another location is selected for the workpiece for forming the workpiece at the new location. The sheet feed roller assembly 40 then moves the workpiece 80 along the Y axis to its selected location in coordination with the desired predetermined and preprogrammed independent movement of the main forming tool assembly 10 along the X axis and the Z axis. In addition, the independent movement of the workpiece 80 is also coordinated with the specified independent movement of the backing roller tool assembly 20 along the Z axis by a control system (not shown). As a result, the desired forming of the workpiece 80 occurs at the selected location.

[0101] Additional coordinates are selected, and the above sequence is continued until the workpiece 80 is fully formed into the desired configuration. Fig.10 and its accompanying description of the process for carrying out the invention.

[0102] FIG. 2A to FIG. 2C A second embodiment (Embodiment 2) of the sheet forming ISF system of the present invention is depicted. This embodiment includes a sheet feed belt assembly 43 for accurately advancing a workpiece 80, a primary forming tool assembly 10, and a secondary forming tool assembly (eg, backing roller tool assembly 20).

[0103] In Example 2, the sheet feed roller assembly 40 of Example 1 is replaced with a sheet feed belt assembly 43, and functions in a similar manner to the sheet feed roller assembly. The assembly includes multiple sets of pulleys 44A-44H and a continuous and endless belt 46 around the rollers. The multiple roller sets rotate in contact with the continuous belt 46 to generate high traction along the Y axis at a predetermined speed when the pulleys 44 rotate. Therefore, the belt 46 preferably clamps and moves the workpiece 80 forward and backward accurately along an axis (shown as the Y axis in Example 2). The configuration and size of the belt 46 are determined and made of a material that is selected to expand the contact area with the surface of the workpiece 80 beyond the contact area of ​​the pulleys 44A-44H of Example 1. The additional surface area contacted by the sheet feed belt assembly 43 of Example 2 on the workpiece 80 increases the clamping force and minimizes possible slippage of the workpiece for achieving even more accurate positioning of the workpiece.

[0104] Alternative embodiments are contemplated, for example, where multiple belts are arranged to contact opposing surfaces of workpiece 80 at least along edge 88 or 89. Further, it is contemplated that only one belt 46 may contact one surface of workpiece 80, with pulleys positioned on opposing surfaces of the workpiece.

[0105] Example 2 (see e.g. Figure 2A ) shows a sheet feed belt assembly 43 having four sets of pulleys (44A and 44B, 44C and 44D, 44E and 44F, 44G (not shown), and 44H) and four belts 46. One set of rollers (44A and 44B) is disposed and positioned along a first edge 88 of a workpiece 80 and on a first (i.e., upper) surface of the workpiece. A second set of rollers (44C and 44D) is disposed and positioned at the first edge 88 of the workpiece 80, but on the opposite (i.e., second or lower) surface of the workpiece. A third set of rollers (44E and 44F) is disposed and positioned along a second edge 89 of the workpiece 80 parallel to the first edge 88 of the workpiece. A fourth set of rollers (44 (not shown) and 44H) is also disposed and positioned at a second edge 89 parallel to the first edge 88 of the workpiece 80, but on an opposite surface of the workpiece.

[0106] As shown, the continuous belt 46 is passed around its pulley sets 44A-44H and contacts the surface of the workpiece 80 along edges 88 and 89 to grip the workpiece 80 and move it to a desired position in the Y direction. The belt 46 is preferably configured and sized to provide consistent traction on the surface of the workpiece 80 for accurately achieving predictable and coordinated movement of the workpiece back and forth along the Y axis.

[0107] At least one of the pulleys 44A or 44B and one of the pulleys 44E or 44F may preferably be actuated by a synchronous motor (not shown) and a control system that coordinates and drives the rotation of the various pulleys and the surrounding belt 46 to preferably move back and forth along a translation axis (shown as the Y axis in Embodiment 2) and position the workpiece 80. Additionally or alternatively, at least one of the pulleys 44C or 44D and one of the pulleys 44G or 44H may also preferably be actuated by a synchronous motor (not shown) to coordinate and drive the rotation of the various pulleys and the surrounding belt to preferably clamp and move the workpiece 80 back and forth along a translation axis (shown as the Y axis in Embodiment 2).

[0108] The pulley 44 of the sheet feed belt assembly 43 includes a core made of steel, aluminum, or another suitable material known in the art. The belt 46 of the sheet feed belt assembly 43 is composed of polyurethane, neoprene, or another suitable material, and is preferably reinforced with strands of fiberglass, aramid, polyamide fiber (such as KEVLAR material), carbon, steel, or another suitable material known in the art. In addition, the belt 46 may be coated with a layer of material such as polyurethane, nitrile, rubber, or another suitable material known in the art to increase the coefficient of friction between the belt and the workpiece 80. The width, thickness, and durometer of the belt 46 are selected to be able to apply precise and consistent traction on the surface of the workpiece 80 for coordinated alignment of the workpiece 80 with the primary forming tool assembly 10 and the secondary forming tool assembly.

[0109] The operation of Example 2, including the main forming tool assembly 10 and the backing roller tool assembly 20, is the same as that described with respect to Example 1, except that the operation of the sheet feed roller assembly 40 of Example 1 is replaced with the operation of the sheet feed belt assembly 43 as described.

[0110] The sheet feed belt assembly 43, the primary forming tool assembly 10 and the backing roller tool assembly 20 may be controlled by different systems (e.g., mechanical, hydraulic) that may interface directly or indirectly with each other and with a computing entity to send and receive information regarding their precise positioning at their desired locations. FIG. 6A to FIG. 6D and FIG. 9 for the motor actuation description and Fig.10 control system.

[0111] FIG. 3A to FIG. 3CA third embodiment (Embodiment 3) of the present ISF system is depicted. This embodiment includes a sheet fixture assembly 50 for advancing 80 a workpiece, a primary forming tool assembly 10 and a backing roller tool assembly 20 .

[0112] In Example 3, a sheet fixture assembly 50 replaces the sheet feed roller and sheet feed belt assemblies of Examples 1 and 2. The sheet fixture assembly 50 includes a rigid frame 51 and a retainer 52. A workpiece 80 is positioned and secured between the rigid frame 51 and the retainer 52, which is capable of safely limiting movement of the workpiece relative to the rigid frame 51. The sheet fixture assembly 50 defines an opening that is configured and sized to accommodate the workpiece 80 between the rigid frame 51 and the retainer 52, while still allowing the workpiece to be secured by the sheet fixture assembly 50 along at least a portion of the periphery of the workpiece. In other words, the opening in the sheet fixture assembly 50 is defined to provide access to the surface of the workpiece 80 for use in performing a forming process by utilizing the main forming tool assembly 10 and the backing roller tool assembly 20, while still allowing the workpiece to be secured within the sheet fixture assembly.

[0113] The holder 52 may include a plurality of clamps (not shown) positioned around the perimeter of the workpiece 80. The clamps engage and / or exert sufficient force on the workpiece 80 and the rigid frame 51 to prevent the workpiece from sliding and maintain its fixed position within the sheet fixture assembly 50. The clamps are preferably provided along multiple edges or all edges of the rigid frame 51 to surround the opening and securely secure the workpiece 80 therein. The clamps or another mechanism for securely retaining the workpiece 80 within the sheet fixture assembly 50 may be selected and positioned to exert a constant, fixed, or adjustable force on the workpiece 80 by manual, hydraulic, electric, or magnetic actuation, in accordance with the prior art.

[0114] In Example 3, the sheet fixture assembly 50 can be advanced in a known manner to move the workpiece 80 back and forth along the Y axis to its desired position in the XY plane. The sheet fixture assembly 50 operates in a similar manner to the sheet feed roller assembly 40 of Example 1. The operation of the main forming tool assembly 10 and the backing roller tool assembly 20 is as described with respect to Examples 1 and 2. For example, the main forming tool assembly 10 is positioned adjacent to one surface of the workpiece 80, which is fixed in its desired position within the sheet fixture assembly 50. The backing roller tool assembly 20 is positioned on the opposite surface and maintained in contact with the workpiece 80.

[0115] By way of illustration, the sheet fixture assembly 50 can be moved by one or more motors (not shown) to advance the sheet fixture assembly and the fixed workpiece 80 back and forth along the Y-axis. Thus, the sheet fixture assembly 50 precisely moves the workpiece 80 back and forth to a desired position, preferably along a translation axis (the Y-axis).

[0116] The operation of Example 3, including the main forming tool assembly 10 and the backing roller tool assembly 20, is the same as that described with respect to Example 1, except that the operation of the sheet feed roller assembly 40 of Example 1 is replaced by the operation of the sheet fixture assembly 50 as described.

[0117] The sheet fixture assembly 50, the primary forming tool assembly 10, and the backing roller tool assembly 20 may be controlled by different systems (e.g., mechanical, hydraulic) that may interface directly or indirectly with each other and with a computing entity to send and receive information regarding their precise positioning at their desired locations to produce the predetermined shape of the workpiece 80 and the resulting desired shape. See also FIG. 6A to FIG. 6D and FIG. 9 for motor actuation and Fig.10 control system.

[0118] Figure 4A and Figure 4B A fourth embodiment (Embodiment 4) of the ISF sheet forming machine of the present invention is depicted. This embodiment is a three-layer assembly including a sheet fixture assembly 60, a secondary forming tool assembly (including a backing flattening tool assembly 30), and a lower platform 63, which are connected and supported by a plurality of columns 64. Embodiment 4 also includes a primary forming tool assembly 10 and a workpiece 80, which have been previously described with respect to Embodiments 1, 2, and 3.

[0119] The sheet fixture assembly 60 includes a rigid frame 61 and a retainer 62 for limiting the movement of the workpiece 80 and for firmly fixing the workpiece 80 at a desired position. The sheet fixture assembly 60 and its components, the rigid frame 61 and the retainer 62, are similar to the sheet fixture assembly 50 of Embodiment 3 in terms of material, design and configuration, but unlike the sheet fixture assembly 50, the sheet fixture assembly 60 is not directly actuated.

[0120] The backing leveling tool assembly 30 in Example 4 includes a leveling rigid plate 31 and a leveling layer of a flexible elastic surface material layer 32 fixed to the surface of the plate 31 adjacent to the workpiece 80. The outer layer of material 32 may also be a leveling outer surface portion of the backing leveling tool assembly 30. The plate 31 may be made of steel, aluminum, or some other suitable rigid material known in the art.

[0121] Similar to the resilient layer 22 of Examples 1, 2, and 3, the resilient layer 32 of Example 4 is made of a resilient, deformable, and compressible material having a durometer selected so that the layer is capable of deforming under the force exerted by the primary forming tool assembly 10 on the workpiece 80 as the workpiece is formed. The material selected for the resilient layer 32 is also capable of substantially returning to its original configuration when the force from the workpiece 80 (originating from the primary forming tool assembly 10) is removed and when the backing roller assembly is moved along the Z-axis away from the second surface of the workpiece as the workpiece is moved to a newly selected position.

[0122] For example, the elastic layer 32 may be made of an elastomer, preferably a polyurethane as described with respect to Example 1. Alternatively, the elastic layer 32 may also be made of rubber, neoprene or another suitable material of durometer, which can be flexible, compressible and deformable when in contact with the workpiece 80, and can be elastic and retractable when no longer in contact with the workpiece. In other words, the durometer of the elastic layer 32 will depend on the values ​​of hardness, compressibility and elasticity of the selected material, which values ​​may vary depending on the material of the workpiece 80 and the final desired shape.

[0123] In Example 4, the durometer range of the elastic layer 32 is generally about Shore 10A to about 80D, preferably about 30A to about 95A. Depending on the hardness of the selected material, the thickness of the elastic layer 32 varies between about 0.01 mm and about 25 mm, preferably about 1.0 mm to about 5.0 mm.

[0124] The elastic layer 32 preferably comprises a preformed sheet of an elastic material (as described above) that is attached to the rigid plate 31 by using an adhesive, a retainer such as a clamp, or another suitable attachment method known in the art. Alternatively, the elastic layer 32 can be fixed by friction means known in the art. Another method for constructing the backing leveling tool assembly 30 is to apply a leveling layer of an adherent liquid version of the above-mentioned elastic material to the upper surface of the plate 32 and allow the material to cure in place so as to be fixed to the plate. The elastic material can be suitably leveled by leveling, machining, grinding, or another manufacturing method.

[0125] In Example 4 (see e.g. Figure 4A and Figure 4B ), four support posts 64 extend between the sheet fixture assembly 60 and the backing flattening tool assembly 30, and continue to extend between the backing flattening tool assembly 30 and the lower platform 63. The support posts 64 can be provided as solid or hollow tubular members. The configuration and size of the posts 64 are preferably determined so that the backing flattening tool assembly 30 can slide freely along the posts in the Z direction so as to maintain continuous contact with the surface of the workpiece 80 during the forming process while the main forming tool assembly 10 applies force on the workpiece.

[0126] exist Figure 4A , the support column 64 is shown as being positioned within a defined opening of the backing leveling tool assembly 30. However, the column 64 may be modified or replaced by another suitable means known in the art that will allow the backing leveling tool assembly 30 to move vertically (i.e., along the Z axis) relative to the workpiece 80 (e.g., including a track system). This sliding movement allows the backing leveling tool assembly 30 to maintain continuous contact with the workpiece 80 while the main forming tool assembly 10 applies force on the workpiece.

[0127] Similar to the operation of the backing roller tool assembly 20 of Examples 1-3, the backing leveling tool assembly 30 can be operated along a single axis (eg, Figure 4A and Figure 4B The workpiece 80 moves about a Z-axis (as shown) and remains nominally flat relative to the sheet fixture assembly 60 and parallel to the XY plane defined by the workpiece 80.

[0128] By way of illustration, the sheet fixture assembly 60 may be moved along the Z axis by one or more motors (not shown). The sheet fixture assembly 60, the main forming tool assembly 10, and the backing flattening tool assembly 30 may be controlled by different systems (e.g., mechanical, hydraulic) that may interface directly or indirectly with each other and with a computing entity to send and receive information regarding their precise and independent positioning in their desired locations. See also FIG. 6A to FIG. 6D The motor actuation description and the description of FIG. 9 and the description of FIG. Fig.10 control system.

[0129] exist Figure 4A and Figure 4B , the forming tool 10 can be moved in the X, Y and Z directions relative to the sheet fixture assembly 60 and the workpiece 80 by different systems (e.g., mechanical or hydraulic systems) not shown. The rigid frame 61 and the holder 62 of the sheet fixture assembly 60 can be fixed to the lower platform 63 via a series of support posts 64. The backing flattening tool assembly 30 including the plate 31 and the elastic layer 32 is positioned between the sheet fixture assembly 60 and the lower platform 63.

[0130] Figure 5 An alternative mode of operation of Example 4 is shown. Figure 5 In the embodiment 4, the embodiment 4 has been incorporated into a vertical machining center 70 (hereinafter referred to as VMC). In this example, the main forming tool assembly 10 is inserted into the spindle assembly 72 of the VMC 70. The lower platform 63 is attached to the table assembly 71 of the VMC 70.

[0131] As about Figure 4A and Figure 4B As discussed, Figure 5, the rigid frame 61 and holder 62 of the sheet fixture assembly 60 may be secured to a lower platform 63 via a series of support posts 64. The backing leveling tool assembly 30, including the rigid plate 31 and the resilient layer 32, is positioned between the sheet fixture assembly 60 and the lower platform 63. The resulting three-layer assembly may be controllably moved relative to the main forming tool assembly 10 in three directions (along the X, Y, and Z axes) via the VMC 70.

[0132] By moving the table assembly 71 with the spindle assembly 72, the VMC 70 provides translational movement along three axes (X, Y, and Z axes) of the workpiece 80 relative to the main forming tool 10. For example, vertical movement of the backing flattening tool assembly 30 along the Z axis can be synchronized via the motion controller of the VMC 70, auxiliary controls, or a combination of both (not shown), as is known in the art. In addition, one or more motors can move the backing flattening tool assembly 30 further along the Z axis toward or away from the workpiece 80 in cooperation with the VMC 70. See also FIG. 6A to FIG. 6D Motor actuation description, description of FIG. 9 and description of FIG. Fig.10 Description of the control system.

[0133] Alternative embodiments using other types of machining centers known in the art (such as, for example, horizontal machining centers and machining centers operating on 5 axes) are possible and contemplated herein. Additional embodiments may also include incorporating the main forming tool assembly 10 and the backing flattening tool assembly 30 into other existing machines in accordance with the art without departing from the principles disclosed herein.

[0134] FIG. 6A to FIG. 6D , Figure 7 and Fig. 8A and Figure 8B Exemplary cross-sectional views of a workpiece 80 are shown, respectively, undergoing a series of incremental forming steps along an illustrative working path in accordance with an embodiment of the present invention.

[0135] FIG. 6A to FIG. 6D Depicted is an exemplary front cross-sectional view of a workpiece undergoing a series of incremental forming steps from a flat sheet (see, e.g., Fig. 6A ) until it is formed into the final configuration 81 (see e.g. Fig.6D ).

[0136] More specifically, FIG. 6A to FIG. 6DA primary forming tool assembly 10, a workpiece 80, and a backing forming tool assembly 90 are shown. The backing forming tool assembly 90 includes a resilient surface material layer 92 (or an outer surface portion of the backing tool assembly 90) secured to a rigid backing 91. The backing forming tool assembly 90 represents any of those secondary forming tool assemblies of any of the previous embodiments, which include a resilient backing roller tool assembly 20 having a resilient layer 22 and a core 21 (see, e.g., Figures 1A to 1C , FIG. 2A to FIG. 2C and FIG. 3A to FIG. 3C ), or a backing leveling tool assembly 30 including an elastic layer 32 and a rigid plate 31 (see, e.g. FIG. 4A to FIG. 4B and Figure 5 ).

[0137] During the forming process, the workpiece 80 is pressed between the main forming tool assembly 10 and the backing forming tool assembly 90. The main forming tool assembly 10 applies a controlled force to one surface of the workpiece 80. As a result, the workpiece 80 deforms and exerts a force on the resilient layer 92. In turn, the resilient layer 92 compresses and exerts a counter force from the opposing surface of the workpiece 80 to support the workpiece at a localized area or contact point around the main forming tool assembly 10. As a result, the workpiece 80 is plastically and permanently formed.

[0138] The elastic layer 92 remains in a compressed state while in contact with the workpiece 80. However, once the backing forming tool assembly 90 is moved from the workpiece 80 to another preprogrammed and predetermined position along the Z axis, the elastic layer 92 returns to its pre-compressed configuration.

[0139] During the forming process, the primary forming tool assembly 10 remains firm due to its hardness and rigidity. Due to its plasticity and flexibility, the workpiece 80 is easily and permanently formed by the force applied thereto by the primary forming tool assembly 10. In turn, the elastic layer 92 is also temporarily deformed due to the force applied thereto by the workpiece 80.

[0140] In operation, the elastic layer 92 may be compressed relative to the Z axis in a range of about 0.001 to about 0.2 inches or more, preferably about 0.005 to about 0.1 inches, depending on the material selected, its thickness, and the size of the workpiece 80.

[0141] exist FIG. 6A to FIG. 6D In the embodiment of the present invention, the main forming tool assembly 10 and the backing forming tool assembly 90 are preferably controlled by an electromechanical positioning system having predetermined or pre-programmed motions that cause local controlled forces on the workpiece 80. In other words, CNC programming techniques are utilized in connection with establishing controlled positioning of the various tools in order to achieve such results and the desired forming of the workpiece 80. Figure 7 , Fig. 8A , Figure 8B and Fig.10 Also described as FIG. 6A to FIG. 6DAn apparatus for controlling the forming process of a workpiece 80 is depicted.

[0142] All embodiments are preferably actuated by such electromechanical devices. A servo motor is a preferred electromechanical drive device. A stepper motor can also be used as an electromechanical drive device. Furthermore, as an alternative, a precision hydraulic system can be used for one or more of the actuation axes of the mechanical system. See also Fig.10 and its accompanying instructions.

[0143] Alternatively, the main forming tool assembly 10 or the backing forming tool assembly 90 or both assemblies may be controlled based on pressure. In this alternative method, either or both of the main forming tool assembly 10 and the backing forming tool assembly 90 are controlled in the Z direction by an electromechanical positioning system that applies a target force on the workpiece 80. This will allow the pressure control tool (or multiple tools) to change its position on the Z axis so as to maintain a predetermined pressure on its corresponding surface of the workpiece 80. In other words, other known CNC programming techniques related to specifying pressure values ​​are utilized. See U.S. Patent No. 7,536,892, the entire contents of which are incorporated herein by reference.

[0144] like Figure 7 As shown, the primary forming tool assembly 10 illustratively moves along an outer tool path 83 in a plane offset from a plane defined by the original workpiece 80. The primary forming tool assembly 10 advances along the Z axis, applying a controlled force to the workpiece 80, such as FIG. 6A to FIG. 6D As shown. When the primary forming tool assembly 10 then moves along the outer tool path 83, the primary forming tool continues to apply force to the workpiece 80 while the workpiece 80 is being formed, and the elastic layer 92 of the secondary forming tool assembly (e.g., the backing forming tool assembly 90) also deforms and applies a controlled opposing force on the workpiece from the opposite surface. As a result, the workpiece 80 is subjected to local forces in the area where the forming tool assembly 10 contacts and is plastically formed along the selected tool path.

[0145] By way of further explanation, Figure 7 A workpiece 80 is depicted having a work area with multiple tool paths, wherein the forming of the workpiece increases toward the center of the workpiece. As a result, once the first tool path 83 is run to completion, the backing forming tool assembly 90 is moved away from the lower surface of the workpiece 80 (along the Z axis) by a predetermined distance, and the main forming tool assembly 10 is moved along the second tool path 84 along the Z axis toward the workpiece 80 to provide sufficient reaction force to the workpiece to counteract the forming force on the workpiece from the main forming tool assembly 10. The backing forming tool assembly 90 moves continuously with the movement of the main forming tool assembly 10 to remain substantially opposite the tip of the main forming tool assembly with the workpiece positioned therebetween. As a result, a localized forming force is maintained on the workpiece.

[0146] The primary forming tool assembly 10 is formed by pressing the workpiece into the elastic layer 92 (see Fig. 6A and Figure 7 ) to shape the surface of the workpiece 80. When completed, the forming process begins again on the next tool path 84 (see Figure 7 ). This process is repeated for each successive tool path (see Figure 6B and Figure 7 ), until the forming process is complete and the workpiece 80 is formed in its final configuration 81 (see Figure 6C , Fig.6D and Figure 7 ).

[0147] like Fig. 8A and Figure 8B As shown, other tool path methods can be used to create configurations with more than one forming or working area 100 per sheet of material. Specifically, Fig. 8A and Figure 8B A workpiece 80 is shown with two separate working areas 100. These figures depict a method for forming multiple shapes in two separate working areas on a workpiece 80 that is undergoing a series of incremental forming steps according to an embodiment of the present invention. The method is applicable to workpieces having one or more working areas.

[0148] Fig. 8A Tool paths 101 to 108 are depicted. Tool paths 101, 103, 105 and 107 apply to a first forming region 100, and tool paths 102, 104, 106 and 108 apply to a second forming region 100.

[0149] Figure 8B An exemplary final front cross-sectional view of a workpiece that has undergone a series of incremental multiple forming steps according to an embodiment of the present invention into its newly formed final configuration 81 is depicted. More specifically, Figure 8B A primary forming tool assembly 10 and a secondary forming tool assembly (e.g., a backing forming tool assembly 90) are shown. The secondary forming tool assembly includes an elastic layer 92 (equivalent to the elastic layer 22 of Examples 1-3 and the elastic layer 32 of Example 4) and a rigid backing 91 (equivalent to the core 21 of Examples 1-3 and the rigid plate 31 of Example 4).

[0150] In this example, the primary forming tool assembly 10 follows tool paths 101-108 in numerical order, i.e., in the order of 101, 102, 103, 104, 105, 106, 107, and finally 108. In this example, tool paths 101 and 102, 103 and 104, 105 and 106, 107 and 108 are located at substantially the same position on the Z axis along the XY plane, respectively.

[0151] According to this illustrative incremental forming method, the primary forming tool assembly 10 is moved somewhere along the length of the tool path 101 to a selected Z-axis position of the tool path 101. The resilient backing forming tool assembly 90 is moved in the Z-axis direction to a Z-axis position substantially identical to the tool path 101 (or a preselected dimensional offset in a positive or negative position in the Z-axis direction) that is substantially identical to the tool path 101. The primary forming tool assembly 10 then continues to apply force along the tool path 101 as the workpiece 80 is formed and the resilient backing forming tool assembly 90 supports the workpiece. When movement along the tool path 101 is complete, the primary forming tool assembly 10 is then retracted in the Z-axis direction, away from the workpiece 80, past the original XY reference plane 82 of the workpiece 80 to the XY clearance plane 109 (see FIG. 1 ). Figure 8B ).

[0152] The clearance plane 109 is located at a sufficient distance from the reference plane 82 to allow the primary forming tool assembly 10 to not contact the surface of the workpiece 80. The primary forming tool assembly 10 then continues to advance to a newly selected XY position over the tool path 102 while still positioned along the clearance plane 109. The primary forming tool assembly 10 then moves toward the workpiece 80 to substantially the same Z-axis position on the tool path 102 as previously selected for the tool path 101.

[0153] As the workpiece 80 is formed and the resilient backing forming tool assembly 90 supports the workpiece, the main forming tool assembly 10 continues to apply force along the tool path 102. As a result, the workpiece 80 is formed along the tool path 102 by substantially the same amount as along the tool path 101. During the movement of the main tool assembly 10 along the tool paths 101 and 102, in this example, the backing forming tool assembly 90 does not change its position on the Z axis.

[0154] The primary forming tool assembly 10 is retracted again in the Z axis direction, away from the workpiece 80, past the original reference plane 82 and back to the clearance plane 109. The primary forming tool assembly 10 then enters the XY position above the tool path 103. The elastic backing forming tool assembly 90 is also moved away from the workpiece 80 to a preselected Z axis position (or a dimensional offset in the positive or negative dimension in the Z axis direction). The primary forming tool assembly 10 then moves to the selected Z axis level of the tool path 103 and advances along the tool path 103. When forming is completed along the tool path 103, the primary forming tool assembly 10 continues to advance to the newly selected XY position above the tool path 104, while still being positioned along the clearance plane 109. The primary forming tool assembly 10 then moves toward the workpiece 80 to substantially the same Z axis position on the tool path 104 as previously selected for the tool path 101.

[0155] As the workpiece 80 is formed and the resilient backing forming tool assembly 90 supports the workpiece, the main forming tool assembly 10 continues to apply force along the tool path 104. As a result, the workpiece 80 is formed along the tool path 104 by substantially the same amount as along the tool path 103. During the movement of the main tool assembly 10 along the tool paths 103 and 104, in this example, the resilient backing forming tool assembly 90 does not substantially change its position on the Z axis.

[0156] The method then repeats and continues for tool paths 105 and 106, 107 and 108 until workpiece 80 is formed to its final shape having been formed multiple times. In other words, those tool paths formed at substantially the same Z axis level are all processed in sequence to form all tool paths having substantially the same Z axis level of the final configuration.

[0157] According to the method of the present invention, multiple forms on a single sheet of material need not have the same final shape or the same final amount of forming. In the case of different configurations that require multiple forming on a single sheet of material, the incremental process described above will begin along a tool path where the least amount of forming is envisioned for the multiple forming. The process then moves to the tool path where the next amount of forming is envisioned, and then continues until all tool path configurations are completed and the final shape is achieved.

[0158] 9A to 9C Depicted are cross-sectional views of various primary forming tool assemblies in accordance with the present invention.

[0159] Fig.9A A primary forming tool assembly 10 is depicted, which comprises a solid tool made of any suitable rigid material, typically hardened steel or engineered ceramics. The tip of the primary forming tool assembly that will contact the workpiece 80 may have any shape. Depending on the application, the tip is preferably spherical. The primary forming tool assembly 10 may also have a surface treatment as known in the art of metalworking tools, such as additional hardening or coating.

[0160] Fig. 9B A primary forming tool assembly 10 is depicted, comprising a tool shaft 12 and a connected tool tip 11. The tool shaft 12 may be made of any suitable material, typically hardened steel. The tool shaft 12 may also have additional surface treatments such as hardening or coating as known in the art of metalworking tools.

[0161] The tool tip 11 is preferably spherical, although other shapes are possible and contemplated. The tool tip 11 may be made of any suitably hard and rigid material, preferably ceramic or steel alloy. The tool tip 11 may be securely fastened to the tool shaft 12 mechanically or by bonding. The tool tip 11 may alternatively be designed to be held by the tool shaft 12 and to rotate freely relative to the tool shaft 12, as described below.

[0162] Fig. 9C A primary forming tool assembly 10 is depicted, comprising a tool shaft 12, a tool tip 11, and a sliding bearing 13 positioned between the tool tip 11 and the tool shaft 12. This embodiment functions similarly to a ballpoint pen with its rolling tip.

[0163] All or part of the primary forming tool assembly 10 (e.g., the tip 11) preferably comprises an engineering grade ceramic material. In other words, 9A to 9C One or more of the components 11, 12 and 13 in each of the forming tool assembly 10 may preferably be made of an engineering ceramic having a hardness greater than the hardness of the workpiece 80. Depending on the actual material of the workpiece 80, many technical or engineering grade ceramics may be used, including oxide ceramics and non-oxide ceramics, such as but not limited to silicon nitride, aluminum nitride, zirconium oxide, silicon carbide and aluminum oxide. Silicon nitride (Si3N4) ceramics are generally preferred. The hardness of the main forming tool assembly 10 and its tool tip 11 is greater than the hardness of the workpiece 80.

[0164] Depending on the size of the workpiece to be formed and the desired final forming details, the tool tip 11 is preferably spherical and has a diameter preferably ranging from about 0.125 inches to about 2.0 inches, more preferably about 0.50 inches to about 1.50 inches for larger workpieces, and preferably about 0.125 inches to about 0.50 inches for smaller workpieces.

[0165] It has also been discovered that incorporating an engineering grade ceramic as part of the primary forming tool assembly 10 minimizes the need for constant lubrication of the workpiece that would otherwise be required with prior art devices. Advantageously, spherical balls of engineering ceramics (e.g., particularly silicon nitride) do not break when used as tool tips 11 in accordance with the methods of the present invention, despite the forces and resulting friction exerted on the workpiece 80. These engineering ceramic tips also create a polished or ground surface for the formed sheet of material (such as sheet metal).

[0166] According to known bearing materials, suitable materials for the sliding bearing 13 include, but are not limited to, ceramics, metals or plastics.

[0167] Fig.10 A partial cross-sectional view of an embodiment of the present invention in combination with a synchronous control system is depicted. Fig.10 A synchronization controller assembly 85 , a non-contact measurement sensor 86 , and a contact measurement sensor 87 are shown. Fig.10 Also shown are a primary forming tool assembly 10 and a secondary forming tool assembly (e.g., a backing forming tool assembly 90). The secondary forming tool assembly includes an elastic layer 92 (equivalent to the elastic layer 22 of Examples 1-3 and the elastic layer 32 of Example 4) and a rigid backing 91 (equivalent to the core 21 of Examples 1-3 (see, e.g., Figure 1A to Figure 1B , FIG. 2A to FIG. 2B and FIG. 3A to FIG. 3B ) and the rigid plate 31 of Example 4 (see for example FIG. 4A to FIG. 4B and Figure 5 ).

[0168] exist Fig.10 In the embodiment, one or more controllers or control modules may be provided for synchronous control operation applicable to the components described in the above embodiments. By way of illustration, the synchronous controller assembly 85 monitors and controls the sheet feed roller assembly 40 of the previous embodiment (see, for example, Figures 1A to 1C ) or sheet feed belt assembly 43 (see e.g. FIG. 2A to FIG. 2C ) or sheet material fixture assembly 50 (see e.g. FIG. 3A to FIG. 3C ) or workbench assembly 71 (see e.g. Figure 5 ) precise positioning ( Fig.10 ), primary forming tool assembly 10 and secondary forming tool assembly 90 (similar to backing roll tool assembly 20 (see e.g. Figure 1A to Figure 1B , FIG. 2A to FIG. 2B and FIG. 3A to FIG. 3B ) or backing leveling tool assembly 30 (see e.g. FIG. 4A to FIG. 4B and Figure 5 )). The synchronization controller component 85 can interact directly with the various subsystems. Alternatively, the synchronization controller component 85 can interact indirectly by obtaining the position information of each subsystem to determine and provide coordinated control.

[0169] exist Fig.10 In the embodiment of the present invention, the synchronous controller assembly 85 can be operated based on NC (numerical control) according to the prior art. The synchronous controller assembly 85 can be adapted to receive CAD data, derive numerical control data from the CAD data, so as to form the workpiece 80 according to the design specifications. The controller assembly 85 can monitor the positioning and forming process of the workpiece 80 via a contact sensor 87 that physically contacts the workpiece 80, or via a non-contact sensor 86 (i.e., a laser or optical measurement system) without physical contact. The control system including the synchronous controller assembly 85, the contact sensor 87 and the non-contact sensor 86 can monitor the position of the workpiece 80 at the beginning of the forming process of the present invention, and preferably repeat the monitoring throughout the forming process.

[0170] according to Fig.10As described above, a non-contact sensor 86 or a contact sensor 87 is provided to measure the amount of forming of the workpiece 80 at a specified location along the workpiece forming path. The resulting measurement from the sensor 86 or 87 is compared with the predetermined amount of forming at the same specified location along the forming path. The resulting comparative measurement is relayed to the controller assembly 85. The controller assembly 85 then adjusts the position of at least one of the main forming tool assembly 10 and the backing forming tool assembly 90 relative to the pre-programmed amount of desired forming along the path so as to form the workpiece into a predetermined shape. See also U.S. Patent No. 7,536,892.

[0171] Although shown in conjunction with the preferred embodiment Fig.10 , but the control system may be utilized with any of the embodiments of the invention described herein.

[0172] Detailed embodiments of the present invention are disclosed herein. However, it should be understood that the disclosed embodiments are merely exemplary embodiments of the present invention that may be embodied in various and alternative forms. The drawings are not necessarily drawn to scale. Some features may be exaggerated or minimized to show the details of particular components. Therefore, the specific structural and functional details disclosed herein should not be interpreted as limiting, but merely as a representative basis for the claims and / or as a representative basis for teaching those skilled in the art to adopt the present invention in various ways.

[0173] Additionally, in the drawings, reference is made to the X, Y, and Z axes of a three-dimensional orthogonal coordinate system with respect to the movement of various components (e.g., sheet feed roller assembly 40 or sheet feed belt assembly 43 or sheet fixture assembly 50 or sheet fixture assembly 60; primary forming tool assembly 10; and backing roller tool assembly 20 or backing flattening tool assembly 30 or backing forming tool assembly 90) all relative to one another. It should be understood that the movement of the various components is intended to be depicted with respect to the movement of each of the other components and a reference plane, if applicable (i.e., defined by the initial configuration of the workpiece prior to incremental forming).

[0174] Additionally, references to certain surfaces are as a first surface or a second surface, an upper surface or a lower surface, or a vertical surface or a horizontal surface, etc. Such directional descriptions are intended to take into account the appropriate X, Y, and Z axes, as shown in the applicable figures.

[0175] In addition, the reference plane Figure 1A , FIG. 6A to FIG. 6D and Figure 8B 82. For simplicity, the reference plane is not shown in other figures, but is intended to be the initial generally flat configuration of the workpiece 80 along the XY plane prior to incremental forming.

Claims

1. A device for incrementally forming a workpiece, the workpiece being a metal or plastic sheet, the workpiece having a first surface and a second surface opposite and parallel to each other, a working area, and defining an XY plane of a three-dimensional orthogonal coordinate system of "X", "Y", and "Z", the XY plane being parallel to the surface, the device being constructed and arranged to incrementally form the workpiece in a series of forming paths, and comprising: a. a primary forming tool assembly positioned adjacent and arranged to face said first surface of said workpiece and constructed and arranged to move into and out of engagement with said workpiece in a direction perpendicular to said XY plane and in all directions parallel to said XY plane, said primary forming tool assembly comprising a tool axis fixedly aligned along the Z direction of said "X", "Y", "Z" three-dimensional orthogonal coordinate system and having a tip facing said first surface of said workpiece; as well as b. a secondary forming tool assembly having a compressible and resilient surface portion disposed facing said second surface of said workpiece and constructed and arranged to move into and out of engagement with said workpiece in a direction perpendicular to said XY plane; wherein one or both of the workpiece and the primary forming tool assembly are constructed and arranged for movement so as to position the primary forming tool assembly within the working area and for causing the tip of the tool shaft to apply a force on the first surface of the workpiece in a direction perpendicular to the XY plane, while the secondary forming tool assembly engages with the second surface of the workpiece and applies an opposing force directly opposing the force applied by the tip of the tool shaft in a direction perpendicular to the XY plane, so that a localized force is applied to the workpiece during forming, wherein the relative movement between the tip of the tool axis of the primary forming tool and the workpiece is limited to translational movement within the three-dimensional orthogonal coordinate system of "X", "Y", and "Z", and wherein, when forming each of the series of forming paths for forming the workpiece, the tip of the tool axis is constructed and arranged to be adjustably positioned at each of a set of predetermined XY coordinates relative to the workpiece parallel to the XY plane, while the tip of the tool axis maintains contact with the first surface of the workpiece at substantially the same predetermined Z coordinate position so as to follow a predetermined forming path relative to the workpiece substantially parallel to the XY plane. 2 . The apparatus of claim 1 , wherein the tip of the tool shaft comprises an engineered ceramic material having a hardness greater than the hardness of the workpiece.

3. The apparatus of claim 1, further comprising a sheet feed assembly constructed and arranged to move the workpiece in a direction parallel to the XY plane.

4. The device according to claim 3, wherein the sheet feeding assembly includes a sheet feeding roller assembly having at least one roller group contacting the respective first and second surfaces of the workpiece, and the roller group is constructed and arranged to move the workpiece in a direction parallel to the XY plane.

5. The apparatus of claim 3 , wherein the sheet feed assembly comprises a sheet feed belt assembly having at least one continuous belt surrounding and contacting a set of rotatable pulleys, the continuous belt being positioned in contact with the first surface or the second surface of the workpiece and being constructed and arranged to move the workpiece in a direction parallel to the XY plane.

6. The apparatus of claim 1, further comprising a sheet material fixture assembly having a rigid frame and a retainer, the retainer being constructed and arranged for: a. The workpiece is firmly held therebetween; and b. defining an opening for accessing the workpiece through the primary forming tool assembly on the first surface of the workpiece and through the secondary forming tool assembly on the second surface of the workpiece.

7. The apparatus of claim 1 , wherein the secondary forming tool assembly is a backing roller tool assembly having a cylindrical configuration and constructed and arranged for rotation about a longitudinal axis extending longitudinally therethrough, the backing roller tool assembly further comprising an inner core and a compressible and resilient outer layer secured thereto facing the second surface of the workpiece, the compressible and resilient outer layer constructed and arranged for: a. When the workpiece is formed by the main forming tool assembly, the workpiece is compressed by the force exerted thereon; and b. elastically returning to its non-compressed shape when the backing roller tool assembly moves away from the second surface of the workpiece.

8. The apparatus of claim 1 , wherein the secondary forming tool assembly is a backing flattening tool assembly, the backing flattening tool assembly comprising a rigid plate and a resilient layer secured thereto, and the resilient layer is positioned adjacent the second surface of the workpiece in a face-to-face relationship, the resilient layer being constructed and arranged to: a. when the tip of the tool shaft of the main forming tool assembly engages the workpiece and applies a forming force on the workpiece, compressed by the force exerted thereon by the workpiece; and b. elastically returning to its non-compressed shape when the backing-smoothing tool assembly moves away from the second surface of the workpiece.

9. The apparatus according to claim 1 further comprises a control system constructed and arranged for simultaneously coordinating the respective movements of the workpiece, the primary forming tool assembly and the secondary forming tool assembly relative to each other, whereby their coordinated movements cause the tip of the tool axis of the primary forming tool assembly to follow the predetermined forming path along the first surface of the workpiece, while the secondary forming tool assembly is simultaneously controlled in a positional relationship relative to the second surface of the workpiece.

10. An apparatus for forming a workpiece comprising a plate, the workpiece having a first surface and a second surface opposite and parallel to each other, and defining an XY plane of an "X", "Y", and "Z" three-dimensional orthogonal coordinate system, the XY plane being parallel to the first surface and the second surface of the workpiece, the apparatus being constructed and arranged to incrementally form the workpiece in a series of forming paths, and comprising: a sheet feed assembly constructed and arranged to move the workpiece in a direction parallel to the XY plane; as well as b. a primary forming tool assembly positioned facing said first surface of said workpiece and comprising a tool axis fixedly aligned along the Z direction of said "X", "Y", "Z" three-dimensional orthogonal coordinate system and facing said first surface of said workpiece, said primary forming tool assembly being constructed and arranged to move: i. in a first direction perpendicular to the XY plane; and ii. In a second direction, the second direction is parallel to the XY plane and perpendicular to the moving direction of the sheet feed assembly to the workpiece; as well as c. a backing roller tool assembly constructed and arranged for movement in a direction perpendicular to said XY plane and having: i. A cylindrical configuration for rotation about a longitudinal axis; as well as ii. an inner core and an outer elastic layer fixed thereto, the outer elastic layer being positioned facing the second surface of the workpiece, the longitudinal axis of the backing roller tool assembly being positioned parallel to the second direction of the main forming tool assembly; wherein the tip of the tool shaft of the primary forming tool assembly and the backing roller tool assembly are constructed and arranged to respectively contact the first surface and the second surface of the workpiece substantially opposite to each other simultaneously, while the tip of the tool shaft of the primary forming tool assembly applies a force on the first surface of the workpiece in the direction perpendicular to the XY plane to form the workpiece, and the backing roller tool assembly applies an opposing force on the second surface of the workpiece that directly opposes the force applied by the tip of the tool shaft, thereby generating a local force in a contact area between the primary forming tool assembly and the workpiece during forming, wherein the relative movement between the tip of the tool axis of the primary forming tool and the workpiece is limited to translational movement within the three-dimensional orthogonal coordinate system of "X", "Y", and "Z", and wherein, in each of the series of forming paths for forming the workpiece, the tip of the tool axis is constructed and arranged to be adjustably positioned at each of a set of predetermined XY coordinates relative to the workpiece parallel to the XY plane, while the tip of the tool axis maintains contact with the first surface of the workpiece at substantially the same predetermined Z coordinate position so as to follow a predetermined forming path relative to the workpiece substantially parallel to the XY plane.

11. The apparatus of claim 10, wherein the force between the tip of the tool shaft of the primary forming tool assembly and the workpiece and the counterforce between the backing roller tool assembly and the workpiece are substantially concentrated at a local forming region of the workpiece.

12. The apparatus of claim 11, wherein the resilient layer of the backing roll tool assembly is constructed and arranged to: a. When the tip of the tool shaft of the main forming tool assembly forms the workpiece, the force exerted thereon by the workpiece is compressed; and b. elastically returning to its non-compressed configuration when the backing roller tool assembly moves away from the second surface of the workpiece.

13. An apparatus according to claim 12, wherein the sheet feed assembly includes a sheet feed roller assembly having at least one roller set contacting the respective first and second surfaces of the workpiece, the roller set being constructed and arranged to move the workpiece in a direction parallel to the XY plane.

14. The apparatus of claim 12, wherein the sheet feed assembly comprises a sheet feed belt assembly having at least one continuous belt surrounding and contacting a set of rotatable pulleys, the continuous belt being positioned in contact with the first surface or the second surface of the workpiece and being constructed and arranged to move the workpiece in a direction parallel to the XY plane.

15. The apparatus of claim 10, wherein the tip of the tool shaft is made of an engineering ceramic material having a hardness greater than the hardness of the workpiece.

16. An apparatus for forming a sheet workpiece into a predetermined configuration, the workpiece having a first surface and a second surface opposite and parallel to each other and defining an XY plane of an "X", "Y", and "Z" three-dimensional orthogonal coordinate system, the XY plane being parallel to the surface of the workpiece, the apparatus being constructed and arranged to incrementally form the workpiece in a series of forming paths, and comprising: a. a backing roller tool assembly constructed and arranged for rotation about a longitudinal axis and having a compressible and elastic outer surface portion, the longitudinal axis of the backing roller tool assembly being arranged to face the second surface of the workpiece and parallel to the XY plane; b. a primary forming tool assembly positioned adjacent to and arranged to face the first surface of the workpiece, the primary forming tool assembly comprising a tool axis fixedly aligned in the Z direction of the "X", "Y", "Z" three-dimensional orthogonal coordinate system and having a tip facing the first surface of the workpiece, and constructed and arranged to apply a force on the first surface of the workpiece in a direction perpendicular to the XY plane to form the workpiece while moving in a first direction parallel to the longitudinal axis of the backing roller tool assembly; as well as c. a sheet material fixture assembly having a rigid frame and a holder constructed and arranged for securely retaining said workpiece therein, said sheet material fixture assembly being positioned parallel to said XY plane and defining openings for accessing said workpiece through said primary forming tool assembly on said first surface of said workpiece and through said backing roller tool assembly on said second surface of said workpiece; wherein the tip of the tool shaft of the primary forming tool assembly and the backing roller tool assembly are constructed and arranged to move in a direction perpendicular to the XY plane so as to contact respective first and second surfaces of the workpiece such that the force applied by the tip of the tool shaft of the primary forming tool assembly on the first surface of the workpiece is offset by an opposing force applied by the backing roller tool assembly on the second surface of the workpiece that directly opposes the force applied by the tip of the tool shaft, thereby locally supporting the workpiece while forming is performed, wherein the relative movement between the tip of the tool axis of the primary forming tool and the workpiece is limited to translational movement within the three-dimensional orthogonal coordinate system of "X", "Y", and "Z", and wherein, in each of the series of forming paths for forming the workpiece, the tip of the tool axis is constructed and arranged to be adjustably positioned at each of a set of predetermined XY coordinates relative to the workpiece parallel to the XY plane, while the tip of the tool axis maintains contact with the first surface of the workpiece at substantially the same predetermined Z coordinate position so as to follow a predetermined forming path relative to the workpiece substantially parallel to the XY plane.

17. The apparatus of claim 16, wherein the contact between the tip of the tool shaft of the primary forming tool assembly and the workpiece and the contact between the backing roller tool assembly and the workpiece are substantially concentrated at a localized forming area of ​​the workpiece.

18. The apparatus of claim 17, wherein the compressible and resilient outer surface portion of the backing roll tool assembly is constructed and arranged to: a. When the tip of the tool shaft of the main forming tool assembly forms the workpiece, the force exerted thereon by the workpiece is compressed; and b. elastically returning to its non-compressed configuration when the backing roller tool assembly moves away from the second surface of the workpiece.

19. The apparatus of claim 18, wherein the primary forming tool assembly includes a tool shaft having a tip, the tip being positioned facing and proximate the first surface of the workpiece and opposite the longitudinal axis of the backing roller tool assembly, the primary forming tool assembly being constructed and arranged to: a. moving the tip of the tool shaft of the primary forming tool assembly into and out of contact with the first surface of the workpiece; and b. selectively applying a force on the first surface of the workpiece so as to shape the workpiece into a predetermined configuration.

20. The apparatus of claim 19, wherein the tip of the tool shaft is made of an engineered ceramic material having a hardness greater than the hardness of the workpiece.

21. An apparatus for incrementally forming a workpiece, the workpiece being from a metal or plastic sheet, the workpiece having a first surface and a second surface opposite to each other located on an XY plane of an "X", "Y", "Z" three-dimensional orthogonal coordinate system, the apparatus comprising: a. a primary forming tool assembly positioned adjacent to and arranged to face the first surface of the workpiece, the primary forming tool assembly comprising a tool axis, the tool axis being fixedly aligned along the Z direction of the "X", "Y", "Z" three-dimensional orthogonal coordinate system and having a tip facing the first surface of the workpiece; as well as b. a secondary forming tool assembly having a compressible and elastic surface material layer and positioned adjacent to and arranged to face said second surface of said workpiece; wherein the workpiece, the primary forming tool assembly and the secondary forming tool assembly are constructed and arranged to move independently relative to each other in a predetermined order and pattern, the primary forming tool assembly and the workpiece are constructed and arranged to move relative to each other along X, Y and Z axes, and the secondary forming tool assembly is constructed and arranged to move relative to the workpiece along the Z axis so that the tip of the tool shaft of the primary forming tool assembly can apply a force on the first surface of the workpiece along the Z axis, and the secondary forming tool assembly can apply an opposing force against the second surface of the workpiece along the Z axis that directly opposes the force applied by the tip of the tool shaft, thereby supporting the workpiece and generating a local force in the contact area between the workpiece and the primary forming tool assembly when the workpiece is formed, wherein the relative movement between the tip of the tool axis of the primary forming tool and the workpiece is limited to translational movement within the three-dimensional orthogonal coordinate system of "X", "Y", and "Z", and wherein, in each of a series of forming paths for forming the workpiece, the tip of the tool axis is constructed and arranged to be adjustably positioned at each of a set of predetermined XY coordinates relative to the workpiece parallel to the XY plane, while the tip of the tool axis maintains contact with the first surface of the workpiece at substantially the same predetermined Z coordinate position so as to follow a predetermined forming path relative to the workpiece substantially parallel to the XY plane.

22. The apparatus of claim 21, further comprising a sheet feed assembly constructed and arranged to move the workpiece along the Y axis in the XY plane of the workpiece.

23. The apparatus of claim 21, wherein the tip of the tool shaft comprises an engineered ceramic material having a hardness greater than the hardness of the workpiece.

24. An apparatus according to claim 22, wherein the sheet feeding assembly includes a sheet feeding roller assembly having at least one roller set, the at least one roller set contacting the corresponding first surface and second surface of the workpiece, and being constructed and arranged to move the workpiece along the Y-axis line in the XY plane.

25. An apparatus according to claim 22, wherein the sheet feed assembly includes a sheet feed belt assembly having at least one continuous belt surrounding and contacting a set of rotatable pulleys, the continuous belt being positioned in contact with the first surface or the second surface of the workpiece, and being constructed and arranged to move the workpiece along the Y-axis in the XY plane of the workpiece.

26. The apparatus of claim 21, further comprising a sheet material fixture assembly having a rigid frame and a retainer, the retainer being constructed and arranged for: a. The workpiece is firmly held therebetween; and b. defining an opening for accessing the workpiece through the primary forming tool assembly and through the secondary forming tool assembly.

27. The apparatus of claim 21, wherein the secondary forming tool assembly is a backing roller tool assembly having a cylindrical configuration and constructed and arranged for rotation about a longitudinal axis, the backing roller tool assembly having an inner core and an outer resilient and compressible layer secured thereto and arranged to face the second surface of the workpiece, the outer resilient and compressible layer being constructed and arranged for: a. when the workpiece is formed by engagement with the tip of the tool shaft of the main forming tool assembly, the workpiece is compressed by the force exerted thereon; and b. elastically returning to its non-compressed configuration when the backing roller tool assembly moves away from the second surface of the workpiece.

28. The device of claim 27, wherein the outer resilient and compressible layer is circumferentially secured to the inner core by a bearing assembly, the bearing assembly facilitating relative movement of the outer resilient and compressible layer with respect to the inner core.

29. The apparatus of claim 21, wherein the secondary forming tool assembly is a backing flattening tool assembly, the backing flattening tool assembly comprising a rigid plate and a resilient layer secured thereto, and the resilient layer is positioned in a face-to-face relationship adjacent the second surface of the workpiece, the resilient layer being constructed and arranged to: a. When the tip of the tool shaft of the main forming tool assembly engages the workpiece and applies a forming force on the workpiece, the force exerted thereon by the workpiece is compressed; and b. elastically returning to its non-compressed configuration when the backing-smoothing tool assembly moves away from the second surface of the workpiece.

30. The device according to claim 21 further includes a control system, which is constructed and arranged to simultaneously coordinate the respective movements of the workpiece, the primary forming tool assembly and the secondary forming tool assembly relative to each other, whereby their coordinated movements cause the tip of the tool axis of the primary forming tool assembly to follow the predetermined forming path along the first surface of the workpiece, while the secondary forming tool assembly is simultaneously controlled relative to the second surface of the workpiece.

31. A method for incrementally forming a workpiece, the workpiece being from a sheet of metal or plastic, the workpiece having at least one working area and having a first surface and a second surface opposite and parallel to each other located adjacent to and defining an XY plane of an "X", "Y", "Z" three-dimensional orthogonal coordinate system, the method being operated to incrementally form the workpiece in a series of forming paths, and comprising: a. Provide a device having: i. a primary forming tool assembly positioned adjacent to and arranged to face the first surface of the workpiece, the primary forming tool assembly comprising a tool axis, the tool axis being fixedly aligned along the Z direction of the "X", "Y", "Z" three-dimensional orthogonal coordinate system and having a tip facing the first surface of the workpiece; as well as ii. a backing forming tool assembly having a compressible and resilient surface portion, said surface portion being positioned adjacent and arranged to face said second surface of said workpiece; The workpiece, the primary forming tool assembly, and the backing forming tool assembly are constructed and arranged for independent movement relative to one another in a predetermined sequence and pattern; b. positioning the tip of the tool shaft of the primary forming tool assembly relative to the workpiece to be adjacent to the first surface of the workpiece within the working area; c. positioning the backing forming tool assembly relative to the workpiece within the working area so as to contact the second surface of the workpiece and relative to the position of the main forming tool assembly; d. advancing the tip of the tool shaft of the primary forming tool assembly in the Z direction toward the workpiece to a predetermined Z coordinate so as to contact and exert a force on the first surface of the workpiece at a localized contact area in the working area in a direction perpendicular to the XY plane, thereby: i forming the workpiece into a predetermined configuration; as well as ii. compressing the backing forming tool assembly to support the second surface of the workpiece during forming and applying an opposing force directly opposing the force applied by the tip of the tool shaft in a direction perpendicular to the XY plane; e. when the tool axis is fixedly aligned along the Z direction of the "X", "Y", "Z" three-dimensional orthogonal coordinate system, translationally moving the tip of the tool axis of the primary forming tool assembly at substantially the same predetermined Z coordinate position relative to the workpiece along a set of predetermined XY coordinates on the XY plane, thereby forming a predetermined forming path relative to the workpiece substantially parallel to the XY plane; f. The main forming tool assembly is retracted from the workpiece; as well as g. Repeating steps "b" to "f" in sequence using incremental values ​​of the Z coordinate and incremental sets of XY coordinates for each incremental Z coordinate value within the working area, the Z coordinate being used to position the main forming tool assembly and the backing forming tool assembly, by repeating the order of steps "b" to "f" to form additional forming paths until the workpiece is fully formed in the working area, wherein after completing a single sequence of steps "b" to "f" and repeating steps "b" to "f" at the incremental Z coordinate values, the workpiece is fully formed in the working area.

32. The method of claim 31 , further comprising: a. providing a controller assembly constructed and arranged to simultaneously coordinate the respective movements of the workpiece, the main forming tool assembly and the backing forming tool assembly relative to each other; b. providing at least one sensor to measure the forming amount of the workpiece at a specified position along the forming path of the workpiece; c. comparing the measurements from the sensor with a predetermined amount of shaping at the same specified position along the path; d. relaying the resulting comparative measurement results to the controller component; and e. adjusting the position of at least one of the primary forming tool assembly and the backing forming tool assembly relative to a preprogrammed forming amount along the path so as to form the workpiece into a predetermined shape.

33. The method of claim 32, further comprising the step of selecting the sensor so that the sensor is non-contact such that the sensor measures the amount of forming of the workpiece without physically contacting the workpiece.

34. The method of claim 32, further comprising the step of selecting the sensor so that the sensor is of a contact type such that the sensor measures the amount of forming of the workpiece by physically contacting the workpiece.

35. The method of claim 31, wherein: The step of compressing the resilient surface portion of the backing forming tool assembly results in a compression of the resilient surface in a range selected from the group consisting of: a range of about 0.001 to about 0.2 inches and a range of about 0.005 to about 0.1 inches.

36. A method for incrementally forming a workpiece, the workpiece being from a sheet of metal or plastic, the workpiece having at least a first working area and a second working area separated from each other, and having a first surface and a second surface located adjacent to each other and parallel to each other on an XY plane defined in an "X", "Y", "Z" three-dimensional orthogonal coordinate system, the method being operated to incrementally form the workpiece in a series of forming paths, and comprising: a. Provide a device having: i. a primary forming tool assembly comprising a tool axis, the tool axis being fixedly aligned along the Z direction of the "X", "Y", "Z" three-dimensional orthogonal coordinate system and having a tip positioned adjacent to and arranged to face the first surface of the workpiece; as well as ii. a backing forming tool assembly having a compressible and resilient surface portion, said surface portion being positioned adjacent and arranged to face said second surface of said workpiece; The workpiece, the primary forming tool assembly, and the backing forming tool assembly are constructed and arranged for independent movement relative to one another in a predetermined sequence and pattern; b. positioning the tip of the tool axis of the primary forming tool assembly relative to the workpiece to simultaneously move to predetermined X, Y, and Z coordinates so as to be adjacent to the first surface of the workpiece within the first working area; c. positioning the backing forming tool assembly relative to the workpiece within the first working region so as to contact the second surface of the workpiece and relative to the position of the main forming tool assembly; d. advancing the tip of the tool shaft of the primary forming tool assembly in the Z direction toward the workpiece to a predetermined Z coordinate so as to contact the first surface of the workpiece in a direction perpendicular to the XY plane within the first working area and exert a force thereon, thereby: i forming the workpiece into a predetermined configuration; as well as ii. compressing the resilient surface portion of the backing forming tool assembly to support the second surface of the workpiece and applying an opposing force directly opposing the force applied by the tip of the tool shaft in a direction perpendicular to the XY plane, thereby generating a local force on the workpiece during forming; e. moving the tip of the tool axis of the primary forming tool assembly relative to the workpiece along a set of predetermined coordinates having substantially the same Z coordinate on the XY plane while the tool axis is fixedly aligned along the Z direction of the "X", "Y", "Z" three-dimensional orthogonal coordinate system, thereby forming a predetermined forming path relative to the workpiece substantially parallel to the XY plane; f in the Z direction the main forming tool assembly is retracted from the workpiece; g. repositioning the tip of the tool shaft of the primary forming tool assembly in the XY plane at a set of predetermined coordinates within the second working region adjacent to the first surface of the workpiece; h. advancing the tip of the tool shaft of the primary forming tool assembly in the Z direction toward the workpiece within the second working region to a Z coordinate substantially the same as the Z coordinate selected for the first working region so as to contact the first surface of the workpiece at a contact point and exert a localized force thereon, thereby: i forming the workpiece into a predetermined configuration; as well as ii. compressing the resilient surface portion of the secondary forming tool assembly to support the second surface of the workpiece during forming; i. moving the tip of the tool axis of the primary forming tool assembly relative to the workpiece in the XY plane along a set of substantially identical predetermined coordinates in the Z direction, the set of predetermined coordinates having substantially identical Z coordinates when the tool axis is fixedly aligned along the Z direction of the "X", "Y", "Z" three-dimensional orthogonal coordinate system, so as to form a predetermined forming path relative to the workpiece substantially parallel to the XY plane; j. retracting the main forming tool assembly from the workpiece in the Z direction; as well as k. Repeating steps "b" to "j" by sequentially utilizing incremental values ​​of the Z coordinate and incremental sets of XY coordinates at each incremental Z coordinate value within each working area until the workpiece is fully formed within each working area, wherein upon completion of a single sequence of steps "b" to "f" and repetition of steps "b" to "f" within each working area, the workpiece is fully formed within each working area.

37. A method for incrementally forming at least one working area of ​​a workpiece, the workpiece comprising a sheet of metal or plastic and initially having a generally flat configuration and first and second surfaces located opposite each other adjacent to and defining an XY plane of an "X", "Y", "Z" three-dimensional orthogonal coordinate system, the method being operative to incrementally form the workpiece in a series of forming paths and comprising: a. positioning a primary forming tool assembly adjacent to said first surface of said workpiece, said primary forming tool assembly comprising a tool axis, said tool axis being fixedly aligned along the Z direction of said "X", "Y", "Z" three-dimensional orthogonal coordinate system and having a tip constructed and arranged to form said workpiece when positively engaged with said workpiece, said tip having a hardness value greater than a hardness value of said workpiece; b. positioning a backing roller tool assembly adjacent to the second surface of the workpiece, the backing roller tool assembly being constructed and arranged for movement in the Z direction, the backing roller tool assembly further having a compressible and resilient outer surface portion, at least one of the backing roller tool assembly and the compressible and resilient outer surface portion being rotatable about a longitudinal axis extending through a center of the backing roller tool assembly; c. advancing the backing roller tool assembly along the Z axis toward the workpiece to contact and support the second surface of the workpiece; d. advancing the main forming tool assembly relative to the workpiece along the Z axis so that the tip engages the first surface of the workpiece and provides a predetermined amount of forming force thereon in a direction perpendicular to the XY plane to form the workpiece; e. maintaining the position of the backing roller tool assembly to provide sufficient opposing force on the second surface of the workpiece to directly oppose the force applied by the tip of the tool shaft in a direction perpendicular to the XY plane, the sufficiency of the opposing force being determined by the degree of compressibility and elasticity of the outer surface portion of the backing roller tool assembly; f. moving said tip of said primary forming tool assembly relative to said workpiece on said XY plane along a set of predetermined coordinates having substantially the same Z coordinates while said tool axis is fixedly aligned along said Z direction of said "X", "Y", "Z" three-dimensional orthogonal coordinate system, thereby following a predetermined forming path relative to said workpiece substantially parallel to said XY plane; g. continuously moving the backing roller tool assembly synchronously with the movement of the main forming tool assembly to maintain the tip of the main forming tool assembly substantially opposite the workpiece therebetween, thereby maintaining a local force on the workpiece; h. The main forming tool assembly and the backing roller tool assembly are retracted from the workpiece; as well as i. continuing to repeat steps "a" to "h" in one or more additional working areas of the workpiece until the workpiece is formed into a predetermined final configuration, wherein after completing a single sequence of steps "a" to "h" in each working area and repeating steps "a" to "h", the workpiece is fully formed in each working area, and the workpiece comprises a metal or plastic sheet.

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