Wind Tower Printing Device And Method

Abstract

A printing system for printing the lower base of a wind tower or the entire wind tower. The system includes a printing device configured to print the coaxial polymeric shells with an empty volume between the shells. The printing device uses the coaxial polymeric shells as driving rails. A concrete material deposition device configured to deposit the concrete material into the empty volume between the polymeric shells, and a rebar handling device is configured to deliver rebars into the volume between the polymeric shells to reinforce the deposited concrete material.

Claims

1. A printing system for printing the lower base of a wind tower, or the entire wind tower, comprising: a printing device configured to print first and second polymeric shells and wherein the polymeric shells are coaxial with an empty volume between them; a concrete material deposition device configured to deposit the concrete material into the empty volume between the first and second polymeric shells; a rebar handling device configured to deliver rebars into the volume between the first and second polymeric shells to reinforce the deposited concrete material; a rebar connection and tying device allowing to connect the different rebar elements into a unified construction; and a driving mechanism that uses the polymeric shells as rails for carrying the printing system weight without transferring weight to the just poured non-dehydrated concrete.

2. The printing system of claim 1, wherein an upper end of the lower base of a wind tower includes at least one cross-section consisting of a monolithic ring cross-section or a structured ring cross-sections.

3. The printing system of claim 1, wherein the printing device comprises an orbiting carriage traveling on a face of the polymeric shells in a reciprocating motion of slightly more than 360 degrees for each side.

4. The printing system of claim 1, wherein the printing device comprises an orbiting carriage traveling on a face of the polymeric shells, and lifting itself from a ground level height to a top of the required wind tower base without the need of an additional lifting or driving unit.

5. The printing system of claim 1, wherein the printing device comprises an orbiting carriage traveling on the polymeric shells, the carriage carries a hose configured to deposit concrete material into the empty volume between the first and second polymeric shells.

6. The printing device of claim 5, wherein an X,Y,Z gantry is installed at the orbiting carriage back side.

7. The printing device of claim 5, wherein the X, Y,Z gantry includes a dispenser for dispensing thermoplastic or thermoset resins for printing the first and the second shells.

8. The printing system of claim 1, wherein at least the printing device moves along a printed polymeric shell circular end face, and wherein the printing device adopts its movement to the shell structure.

9. The printing system of claim 1, wherein the printing device includes wheels facilitating the printing device movement on a foundation base plate.

10. The printing system of claim 1, wherein a central plug and a rotating arm act as a compass and facilitate printing accurate shell circles on a foundation base plate.

11. The printing system of claim 1, wherein an optical target and an optical illuminator facilitate measurement of the height above a foundation base plate and the deviation from the center of its location.

12. The printing system of claim 1, wherein the rebar handling device is configured to handle standard construction rebar with at least two sleeves and at least two pressing disks on its edges.

13. The printing system of claim 12, wherein the rebar handling device is an electromagnetic device that is configured to pick up the rebar from a stationary rebar stack.

14. The printing system of claim 12, wherein the rebar handling device is configured to lift a unified construction rebar upwards using a controlled winch.

15. The printing system of claim 1, wherein an open platform stores a plurality of standard rebars.

16. The printing system of claim 1, further including a robotic arm configured to pick the unified construction defining a rebar module and insert it above a previous assembled rebar module.

17. The printing system of claim 16, wherein the robotic arm includes a press gripper, the gripper configured to insert the rebar module to the previously delivered rebar module using pressure seat by the sleeves.

18. The printing system of claim 17, wherein the gripper is configured to generate contra reaction by a pressing disk located on a previously installed rebar module.

19. The printing system of claim 1, further including a robotic arm with a gripper, the gripper configured to insert a warping ring and warp it around both newly inserted and the adjacent construction rebar modules, thus performing tying between the neighbor rebar modules.

20. The printing system of claim 1, further including a robotic arm holding a concrete material dispenser, the arm is configured to support movement in radial direction simultaneously with the device motion in circular direction to allow a thin layer of concrete casting.

21. The printing device of claim 20, wherein material dispenser is configured to deposit the thin layer of concrete casting in a repeated manner until a required casting height is achieved.

22. A method of additive manufacturing of the lower base of a wind tower, or the entire wind tower, comprising: providing a printing device configured to print the first and second polymeric shells and wherein the polymeric shells are coaxial with an empty volume between them; providing a concrete material deposition device configured to deposit the concrete material into the empty volume between the first and second polymeric shells; and utilizing a rebar handling device configured to deliver rebars into the volume between the first and second polymeric shells to reinforce the deposited concrete material; wherein the rebar handling device inserts new rebar edges into conical edges of a previous rebar of a lower layer, and a gripper presses the new rebar to the adjacent rebar of the same layer level.

23. The method of claim 22, wherein the polymeric shell printing is performed while orbiting around the wind tower base center.

24. The method of claim 22, wherein to ensure good filling of the empty volume, the concrete material deposition is performed by pouring thin layers of concrete, one on top of the other.

25. The method of claim 22, wherein the concrete material deposition height is less than rebar height on 5 to 15 mm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] To understand the apparatus and method and to see how they could be carried out in practice, examples will now be described, by way of non-limiting example only, with reference to the accompanying drawings in which identical referral numbers mean identical or similar parts:

[0037] FIG. 1 is an example of an overall view of the orbiting printing system;

[0038] FIGS. 2A and 2B are examples of a cross-section of the wind tower base;

[0039] FIGS. 3A and 3B are examples of the typical shell printing unit of the orbiting printing system;

[0040] FIG. 4 presents the shell end face position as rails for the orbiting printing systems;

[0041] FIG. 5 is an example of the wheels system of the shell printing unit of the orbiting printing system;

[0042] FIG. 6 is an example of the central plug and a pair of compasses that is in use in the foundation base plate height for the shell printing initiation;

[0043] FIG. 7 is an illustration of the radial and height optical location sensing of the orbiting printing system versus the tower center;

[0044] FIGS. 8A and 8B are examples of typical construction rebar;

[0045] FIG. 9 is an example of the winch that transports the rebar module to the orbiting printing system;

[0046] FIG. 10 is an illustration of the robotic arm that installs the rebar;

[0047] FIG. 11 illustrates the installation of the rebar on the rebar of the previous layer;

[0048] FIG. 12 is an illustration of the tying of the rebar to the adjacent rebar of the same layer; and

[0049] FIG. 13 illustrates the concrete casting step to reach the required casting level.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

[0050] The present document discloses an automated method and apparatus for manufacturing wind tower bases. The automated manufacturing method applies to wind tower bases and other 3D objects that are manufactured by preparing a casting form and casting into the form a build material. The suggested method supports on-site manufacture of wind tower bases, reducing the manufacturing cost and providing a better degree of manufacturing flexibility.

[0051] FIG. 1 is an example of an overall view of the printing system, including an orbiting carriage. An orbiting carriage (10) is circling around the current tops of the wind tower base (20). Orbiting carriage (10) travel could be analyzed in the cylindrical axes system RZ. The orbiting radius R at every height Z depends on the wind tower base design. Orbiting carriage (10) includes polymeric extrusion or dispensing devices that print the outer shell (30) and the inner shell (40) of the wind tower base (20) according to the design. At the same time, the center line (50) remains the reference point. The orbiting carriage printing device prints the first (outer) (30) and second (40) (inner) polymeric shells. The polymeric shells (30 and 40) are coaxial with an empty volume between them. Referral numeral (60) marks a foundation base plate on which the wind tower base (20) is built.

[0052] Usually, the wind tower bases are made from concrete material. A concrete material deposition device (44) deposits the concrete material (46) into the empty volume between the first (30) and second (40) polymeric shells. The printing system does not perform more than a single turn in both options. This eases up the concrete material delivering hose connection and winch connection (FIG. 9) to the stationary support systems at the foundation base plate (60) level.

[0053] The printing system does not perform more than a single turn. This eases up the concrete delivering hose connection and winch (FIG. 9) connection to the stationary support systems at the foundation base plate (60) level.

[0054] Insertion of metal rebars in the concrete improves the bending properties of the concrete. A rebar handling device (FIGS. 8 and 10) is configured to deliver rebars into the volume between the first (30) and second (40) polymeric shells to reinforce the deposited concrete material. The rebar handling device includes a rebar connection and tying device, allowing to connect of the different rebar elements into a unified construction.

[0055] For each printed layer at any height Z, the orbiting angle is 0<<360 (full circle maximum). The temporary height Z (temporary wind tower base height) is measured from the foundation base plate (60).

[0056] The wind tower base design can vary due to many aspects. The design cross-section can contain a monolithic ring or structured concrete material ring. FIG. 2A is an example of a cross-section of a monolithic ring (32) design of the wind tower base.

[0057] FIG. 2B presents an example of a cross-section of a structured concrete material (34) ring design of the wind tower base. In both cases, the inner printed shell (40) used as rails for the orbiting carriage (10) printing device.

[0058] The shell structure can be simple, for example, two concentric rings in the monolithic cross-section case, or can be complexin the structured cross-section case. Referral number (36) marks empty spaces that continue along the height of the wind tower base. The same printing system could print both designs. As explained above, the printing process prints the next layer and the orbiting carriage (10) is riding on the current layer. This means the printing system should be mounted at the back side of the orbiting carriage (trailing edge). The orbiting carriage (10) is large and heavy and driven on low friction material (the shell polymeric material). In an additional example, the printing system could be mounted on a local cartesian gantry added to the orbiting system and not directly on the orbiting carriage. The shell printing procedure is as follows:

1) the orbiting carriage (10) is advancing in a discrete arc (sector) advance mode;
2) the printing system of the orbiting carriage prints the required layer design using cartesian gantry (as in most 3D printers) till completion of the sector;
3) The orbiting carriage (10) is shifting to the next sector, where there is a handshake between the currently printed layer and the next layer all around. At this stagethe next layer becomes the current layer.

[0059] FIGS. 3A and 3B present the shell printing system. The orbiting system (10) circles in the relevant R, in the direction. At the rear of the orbiting system, a cartesian gantry is assembled. Motorized linear stage (70) serves as a guide on which the carriage (80) travels in x-direction. Linear stage (90), which is assembled on carriage (80) serves as a guide on which the carriage (100) moves in Y-axis direction. The polymeric material dispenser (110) is assembled on carriage (100), allowing shell printing as described above.

[0060] The wind tower base that should be printed is having a cone shape, as the bending moment of inertia should be larger while closer to the tower base. Due to the said cone shape of the tower, the polymeric shells (30 and 40) used as rails and have a different geometry per different layer heights (Z). FIG. 4 presents this variation in the rail locationvariation that the wheel system must adopt itself to. A driving mechanism that uses the polymeric shells as rails for carrying the printing system weight does not transfer the weight to the just poured concrete. R.sub.O indicated the outer ring. R.sub.I indicates the inner ring. Bottom/top indicates the level in Z (height) direction.

[0061] The wheel system of the orbiting system is presented in FIG. 5. The wheel system is constructed on two platesthe outer plate (150) and the inner plate (160). These plates are carried on the rails (on an end face of the polymeric shells) using two lines of motorized high friction wheels (170). The driving motors (180) are located on the outer sides of plates (150 and 160). A drive screw (190) operated by a motor (200) ensures that the line of the side wheels (185) from both sides are attached to the wind tower side surfaces. Plates (150) and (160) are kept aligned to each other using two guiding rails (210). When the printing process starts, and the shells are supposed to be printed on the base plate surface, the friction wheels (170) are higher than the surface and cannot function. Four ground-level wheels (220) driven by motors (180) from both sides, are handling the ground level motion. (Initially, the ground-level wheels move over foundation plate (60) (FIG. 1). While using the friction rollers, the shell printing level has a constant distance in Z axis to these wheels, which is the printed shell layer thickness. On the other hand, while using the ground-level wheels (220), the wheels stay at ground level, and the printing level raises in Z-axis direction for each new layer. In this case, the printing level distance of the shells from the ground level wheels (220) is not constant. The distance of the shells from the wheels continues to vary till the friction wheels will touch the shells and will lift the orbiting system (causing the ground wheels to be airborne) to the regular riding on the shell end faces scenario. Because of this, the printing system (presented in FIG. 5) could be mounted on motorized Z stages that compensate for this initial variation. The outer plate (150) supports one stage (250), and the inner plate (160) supports the other Z stage (240).

[0062] While printing on ground level, the shells (serving as rails) are not existing or are not functional yet. FIG. 6, which is an example of the central plug and a pair of compasses that are in use in the foundation base plate height for the shell printing initiation. A central plug 300 installed on the foundation plate (60) in the wind tower center assists in maintaining the circular shape. A rotating arm acts as a compass arm (310) and connects the orbiting system (10) to the plug (300), ensuring an accurate circle when the system is transported by the ground wheels (220) and their motors (180) (FIG. 5).

[0063] Concurrently with the orbiting system (10) movement on the shell rails, it is possible to measure the height from the foundation plate (ZO) and the radial deviation (R). FIG. 7 is an illustration of the radial and height optical location sensing of the orbiting system versus the tower center. An optical target (320) is assembled on the central plug (300) a fixed arm (330) is installed on the orbiting carriage (10). When the orbiting system is moved to the next sector, Z and R are measured. These values are used as the initial setting of the X, Y,Z gantry system for every sector that the dispenser prints.

[0064] Standard constructing rebars are the basic reinforcement of the wind tower base concrete. The depth of the casting cavity (generated by the polymeric shells) is limited, and thus the length of rebar construction is limited. The rebar should be firmly connected to its neighbors (bottom and side-wise). The bottom connection is via special sleeves 410. The side connection is via automatic tying. Sleeves 410 include a conical guide 414 that guides the rebar to a proper coupling with the earlier inserted rebar. The standard or typical construction rebar module (380) is presented in FIGS. 8A and 8B. The standard or typical construction rebar is a rectangular rebar construction made of four steel bars (376) and welded connection rods (372). Two pressing disks (400) are connected on one edge of two opposite side steel bars 376. Connection sleeves (410) are welded at the other side of these bars.

[0065] FIG. 9 is an example of a winch that transports the rebar module to the orbiting system. The standard rebar modules (380) could be hocked by a hook or an electromagnet (480) that is connected to a lifting rope (470). The electromagnet (480) picks the standard rebar module from the stationary rebar module containers (460) and lifts it using a winch (490) to the orbiting system (10). The standard rebar modules consume a large volume and have a large weight. Thus, it is impractical to store on the orbiting system quantity of rebar modules that is sufficient for a full circle of the system. Several stationary rebar containers (460) could be arranged around the wind tower base to facilitate correct rebar modules loading.

[0066] When the standard rebar modules (380) stay on the orbiting system, a robotic arm picks the standard rebar module (380) and places it on the standard rebar module from the previous layer. Then, a gripper presses the rebars to ensure a stiff connection. Finally, the new rebar is tied to the adjacent rebar of the same level. FIG. 10 presents the robotic arm that installs a standard rebar module. The orbiting system (10) holds a stuck of standard rebar modules (380) on an open platform. A robotic arm (510) lifts the rebar module from its stuck past the outer shell (30) and releases it on the previously assembled module (530) that is already covered by the casted concrete layer (520).

[0067] FIG. 11 illustrates the installation of the standard rebar module on the standards rebar module of the previous layer.

[0068] In order to install the standard rebar module (380), the robotic arm (510) includes a gripper (550) that attaches the previous standard rebar module (530) to the currently assembled standard rebar module (450). The attachment process generates a pressure seat of the last standard rebar module (530) in the sleeves (410) of the new standard rebar module (380). The pressing disk (400) provides a contra-reaction.

[0069] FIG. 12 is an illustration of the tying of the standard rebar module to the adjacent standard rebar module of the same layer. Two sets of rebar modules (380) are installed above two units of previous layer modules (530) that are cast in the concrete layer (600) (FIG. 13). A steel warping ring (620) is inserted downwards by the robotic arm to tie the adjacent modules.

[0070] After completion of the standard rebar reinforcement installation, the concrete is cast. The concrete can be delivered from the ground level using standard concrete delivering equipment. The robotic arm holds the dispensing nozzle. To ensure concrete filling and leveling of the cast concrete, the orbiting system can move back and forth in small steps while the robotic arm scans the orthogonal direction.

[0071] FIG. 13 illustrates the concrete casting step helping to reach the required casting level. The robotic arm holds the casting nozzle (700). The robotic arm passes the nozzle (700) above the outer shell rail (polymeric wall) (40) and dispenses the concrete in two scanning motionsalong the railsby the orbiting system (10), and across the rails (30 and 40)by the robotic arm. To level the thin layer of concrete could be casted in each circling cycle. The casting process is completed while the cast concrete level reached the correct height where only the edges of the rebar modules are exposedto allow insertion of the next rebar module level.

[0072] Several examples have been described. Nevertheless, it will be understood that various modifications may be made without departing from the disclosed method, device's spirit, scope, and method of use. Accordingly, other examples are within the scope of the following claims.