阅读说明：本技术 用于铝片材的自动拆堆的涡流坯料分离 (Eddy current stock separation for automatic unstacking of aluminum sheets ) 是由 兰德尔·迪维里 拉尔夫·康拉德 小S·乔治·勒基 安德烈·伊林里奇 弗朗哥·伦纳迪 塞思· 于 2019-05-29 设计创作，主要内容包括：本公开提供“用于铝片材的自动拆堆的涡流坯料分离”。一种将坯料从堆叠中分离的方法,包括：将磁场发生器定位在靠近所述堆叠的上部部分的周边边缘的固定位置中；激活所述磁场发生器,使得产生涡流并产生在背离所述堆叠的最顶部坯料的方向上的力矢量；以及通过所述涡流推动紧靠在所述最顶部坯料下方的一个坯料或多个坯料远离所述最顶部坯料。(The present disclosure provides "vortex blank separation for automatic unstacking of aluminum sheets. A method of separating a blank from a stack, comprising: positioning a magnetic field generator in a fixed position proximate a peripheral edge of an upper portion of the stack; activating the magnetic field generator such that eddy currents are generated and a force vector in a direction away from a topmost blank of the stack is generated; and urging a billet or billets immediately below the topmost billet away from the topmost billet by the vortex.)

1. a method of separating a blank from a blank stack, comprising:

Positioning a magnetic field generator in a fixed position proximate a peripheral edge of an upper portion of the stack;

Activating the magnetic field generator such that eddy currents are generated and a force vector in a direction away from the topmost billet is generated; and

Pushing at least one blank immediately below the topmost blank away from the topmost blank.

2. The method of claim 1, wherein the blank is an aluminum alloy material.

3. The method of claim 1, wherein the magnetic field generator is an electromagnet.

4. The method of claim 1, wherein the magnetic field generator is a rotating assembly of permanent magnets having alternating north and south poles.

5. the method of any one of the preceding claims, further comprising: injecting air to one side of the stack while the individual blanks are separated by the vortex.

6. The method of claim 1, wherein the width of the billet is between about 25mm to about 3000mm, the length of the billet is between about 25mm to about 3000mm, the thickness of each billet is between about 0.5mm to about 6.0mm, and the height of the billet stack is between about 1mm to about 2000 mm.

7. The method of claim 1, further comprising the step of moving the topmost blank to a subsequent manufacturing operation.

8. The method of claim 1, wherein the magnetic field generator displaces only one sheet at a time.

9. The method of claim 1, wherein the gravitational direction is between 90 degrees and 75 degrees as measured from a forward face of the blank.

10. An apparatus for separating blanks from a stack, comprising:

A fixed magnetic field generator; and

A clamp configured to hold and translate the billet stack past the fixed magnetic generator such that a peripheral edge of an upper portion of the stack is continuously positioned proximate the fixed magnetic field generator,

wherein eddy currents from the fixed magnetic field generator force a billet immediately below a topmost billet of the stack to separate from the topmost billet of the stack and fall under gravity.

11. The device of claim 10, wherein the magnetic field generator comprises a multi-phase winding.

12. The device of claim 10, wherein the magnetic field generator is a rotating assembly of permanent magnets having alternating north and south poles.

13. The apparatus of claim 10, further comprising an air knife configured to inject air into the stack as the blanks are separated by the vortex.

14. The apparatus of claim 10, further comprising a transfer mechanism configured to move the topmost blank to a subsequent manufacturing operation.

15. The apparatus of claim 10, wherein the billet stack is not injected with any current through physical contact.

Technical Field

The present disclosure relates to a material handling machine and method, and more particularly, to an apparatus and method for separating blanks.

Background

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

in material forming operations, such as stamping operations, the stack of blanks is typically positioned adjacent to a stamping press and automatically fed into the stamping press by a material handling machine (such as a material handling robot). The tool and die surfaces of the punch receive and form the blank into a desired shape. The robot includes an end effector that moves to a position above the stack of blanks, grabs and lifts the uppermost blank from the stack, and feeds the uppermost blank into the press.

To facilitate the grasping operation of the end effector, the stack of blanks may be unstacked or separated before the end effector grasps the uppermost blank. Typical unstacking methods are not suitable for high volume manufacturing cycle times that require automated, fast, and robust unstacking of blanks. If the robot picks up two or more blanks, the system experiences an interruption and stops the line, resulting in downtime for the manufacturing process.

Moreover, typical unstacking methods are not suitable for picking up various stock materials having different dimensions. For example, a typical unstacking method that works with steel stock may not work with aluminum stock.

The present disclosure addresses these problems associated with unstacking apparatuses with respect to material blanks and the limitations of handling only certain materials.

Disclosure of Invention

In one form, there is provided a method of separating a blank from a stack of blanks, the method comprising: positioning a magnetic field generator in a fixed position proximate a peripheral edge of an upper portion of the stack; activating the magnetic field generator such that eddy currents are generated and a force vector in a direction away from the topmost billet is generated; and urging a billet or billets immediately below the topmost billet away from the topmost billet by the vortex.

In other features, the blank is an aluminum alloy material and the magnetic field generator is an electromagnet. The magnetic field generator is a rotating assembly of permanent magnets having alternating north and south poles. The method further comprises the following steps: injecting air to one side of the stack as the individual blanks are separated by the vortex, and moving the topmost blank to a subsequent manufacturing operation. The magnetic field generator displaces only one sheet at a time. The width of the billet is between about 25mm to about 3000mm, the length of the billet is between about 25mm to about 3000mm, the thickness of each billet is between about 0.5mm to about 6.0mm, and the height of the billet stack is between about 1mm to about 2000 mm. The direction of gravity is between 90 degrees and 75 degrees as measured from the forward face of the blank.

According to other features, the magnetic field generator includes a multi-phase winding. The magnetic field generator is a rotating assembly of permanent magnets having alternating north and south poles. The apparatus may further comprise: an air knife configured to inject air into the stack as the blanks are separated by the vortex; a transfer mechanism configured to move the topmost blank to a subsequent manufacturing operation; a controller configured to transmit a signal to the clamp to cause translational movement thereof; and a position sensor in communication with the controller to transmit the position of the clamp to the controller. In one form, the transport mechanism comprises: a plurality of suction cups configured to hold the topmost blank of the stack; and a robot having an end effector for holding the stack of blanks. Preferably, the stack of blanks is not injected with any current by physical contact. In one form, the vortex produces a force vector in a direction between 90 degrees and 75 degrees as measured from the forward face of the blank.

Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

Drawings

The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:

Fig. 1 is a schematic view of an apparatus for separating blanks from a stack of blanks constructed in accordance with the teachings of the present disclosure.

FIG. 2 is a schematic view of one form of a magnetic field generator operable with the device of FIG. 1 in accordance with the teachings of the present disclosure;

FIG. 3 is a schematic view of a blank stack and a variation of a magnetic field generator operable with the apparatus of FIG. 1 in accordance with the teachings of the present disclosure;

FIG. 4 is a schematic view of a blank stack and another variation of a magnetic field generator operable with the apparatus of FIG. 1 in accordance with the teachings of the present disclosure;

fig. 5 is a flow chart of a method for separating blanks from a stack according to teachings of the present disclosure.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Detailed Description

the following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.

Referring to fig. 1, a material handling device 10 for separating blanks from a blank stack and for moving the separated blanks to a desired location in accordance with teachings of the present disclosure is shown. In one form, the material handling apparatus 10 is used as part of a stamping press (not shown) in manufacturing operations that use electrically conductive stock materials, such as aluminum and steel alloys. In general, the material handling device 10 includes a transport mechanism (such as a robot 12), a fixed magnetic field generator 16, an optional air knife 18, and a clamp 20 for holding and supporting a blank stack 22.

the robot arm 12 may include a robot arm 13 and an end effector 14 attached to the robot arm 13. The end effector 14 may include a plurality of suction cups that supply vacuum via the hose 15 so that the end effector 14 applies suction to securely grasp and move the blanks separated from the blank stack 22. Alternatively, the end effector 14 may comprise a multi-finger gripper or any conventional device capable of grasping and moving separate blanks. The separated blanks are moved by the end effector 14 and fed into a punch press (not shown) wherein the robotic arm 13 moves back and forth between the punch press and the stack of blanks 22 until all blanks in the stack have been sequentially fed into the punch press. (for simplicity of illustration, only the portion of the robot 12 is shown via the schematic inset 11).

As described in more detail below, the magnetic field generator 16 is used to remove one or more unwanted blanks adhered to the topmost blank 23 as the end effector 14 grasps the topmost blank 23 so that the topmost blank 23 can be separated from the remaining blanks in the blank stack 22 to avoid the end effector 14 inadvertently separating more than one blank. More specifically, the end effector 14 may grasp more than one blank at a time from the stack of blanks 22 using its suction force. The magnetic field generator 16 generates a repulsive force F to push any unwanted billet or billets adhered to the topmost billet 23 downward. The unwanted blanks adhered to the topmost blank 23 may be further separated with the aid of gravity G, rather than separating individual blanks as in conventional blank separation devices. Furthermore, no device/component of the material processing apparatus 10 physically contacts an individual blank.

Referring to fig. 2, in one form, the magnetic field generator 16 is a solenoid 17 that employs multi-phase windings to generate a moving (translating) magnetic field M and eddy currents 19 that generate a force vector F for separating unwanted blanks adhered to the topmost blank 23 from the topmost blank 23. In one form, the multi-phase winding may be a three-phase winding. The magnetic field generator 16 is fixed and configured such that the force generated by the eddy currents 19 pushes any unwanted billet adhered to the topmost billet 23 downwards, as shown in fig. 1, the separation of which is further assisted by gravity G. The direction of the magnetic force generated by the eddy currents 19 of the magnetic field generator 16 is determined from the charge quantity and the vector product of the charge velocity and the magnetic field according to equation 1:

F _B ═ qv x B (equation 1) where:

F _B -magnetic force vector

q is the amount of charge

V is the velocity vector of the charge

B is a magnetic field vector

Thus, the magnetic field generator 16 is configured such that the direction of the force of the eddy currents 19 for separating unwanted blanks from the topmost blank 23 is downwards, in the direction of gravity G, as shown. Depending on the application, force F may range from 5 pounds to 200 pounds, and may further vary from these exemplary values.

The material processing apparatus 10 may optionally include a controller 24 for actuating the clamp 20 to move the blank stack 22 up and down in the Z-direction. The controller 24 is configured to move the clamp 20 and position the billet stack 22 to a predetermined height relative to the fixed magnetic field generator 16 to achieve an optimal separation force between the unwanted billet disposed immediately below the topmost billet 23 and the topmost billet 23. The gripper 20 moves the blank stack 22 gradually upward from the raised position and in the Z direction so that the peripheral edge of the upper portion of the stack is continuously positioned adjacent the fixed magnetic field generator 16. A position sensor 30 may be disposed at the clamp 20 and in communication with the controller 24 to transmit a signal to the controller 24 corresponding to the position of the clamp 20.

Optionally, the air knife 18 is configured to inject air into the stack of blanks 22 as the end effector 14 draws the topmost blank 23, and separates the blank immediately below the topmost blank 23 from the topmost blank 23 by repulsive forces F generated by the local eddy currents of the magnetic field generator 16. The robot 12 is configured to move the topmost blank 23 that has been separated from the blank stack 22 to a target location for a subsequent manufacturing operation.

Referring to fig. 3, another form of magnetic field generator 16' is shown, which is disposed adjacent the blank stack 22 and includes a rotor 25 and a plurality of magnets 26 to form a rotating assembly, the plurality of magnets 26 being permanent magnets. Similarly, the magnetic field generator 16' does not contact the billet stack 22. The plurality of magnets 26 are arranged to extend in the radial direction of the rotor 25 and spaced apart in the circumferential direction of the rotor 25, with north poles (N) and south poles (S) being alternately arranged.

The rotation of the magnets 26 with alternating polarity produces a constantly changing magnetic field that induces eddy currents in the nearby conductors, i.e., in the edges of the blank 22. The magnetic force is equal to the product of the current, the magnetic field and the length of the given conductor, which in this case is the billet immediately below the topmost billet 23. The interaction between the magnetic field generated by the magnetic field generator 16 and the eddy currents in the billet 22 generates an opposing repulsive force F between the billet 22 and the rotating magnet 26 that acts to move the edge of the billet immediately below the topmost billet 23 away from the topmost billet 23. The blank immediately below the topmost blank 23 then falls due to gravity. The repelling force F is in a direction defining an angle θ, in one form of the present disclosure, between 75 ° and 90 ° with respect to the front face of the blank 22. The opposing repulsive forces F create a target "billet fanning" effect, wherein the generated magnetic forces are generated in a controlled and targeted manner for separating the billets 22.

the magnitude of the opposing repulsive force F depends on the rotational speed of the rotor 25, the magnetic field strength of the magnet 26, and the diameter of the rotor 25. Thus, the repulsive force F generated by the eddy currents and the magnetic field can be carefully tuned according to the specifications (e.g., size, thickness, material) of the blank 22.

Referring to fig. 4, another variation of a magnetic generator 16 "constructed in accordance with the teachings of the present disclosure includes a sloped surface 42 facing an edge of the blank stack 22, and an array of electromagnets 44 mounted along the sloped surface 42 and disposed proximate the edge of the blank 22. Similarly, the magnetic field generator 16 "does not contact the edge of the blank stack 22. The electromagnet array 44 is computer controlled and is operable to induce eddy currents in the edge of the blank 22 by varying the magnetic field generated by the electromagnet array 44. A computer (not shown) controls the electromagnet array 44 such that the electromagnetic field moves relative to the edge of the blank 22, thereby generating an opposing repulsive force F between the blank 22 and the electromagnet array 44. The electromagnetic field theta moves at an angle between 90 degrees and 75 degrees relative to the front face of the blank 22. The opposing repulsive forces F in the edge of the billet serve to push the billet down against the one disposed below the topmost billet. Also the unwanted blank immediately below the topmost blank 23 is pushed downwards in the direction of gravity. This feature is one of several features that distinguish the teachings of the present disclosure from those of the prior art. Furthermore, the material handling device 10 and the various forms of magnetic field generators 16/16'/16 ″ advantageously do not inject any electrical current into the blank stack 22 through physical contact, which makes the operations for separating and moving blanks during various manufacturing operations (such as stamping) simpler and more efficient.

Referring now to fig. 5, a method 50 of separating a blank from a blank stack 22 and moving the separated blank to a target site begins with positioning the magnetic field generator 16 in a fixed position proximate a peripheral edge of an upper portion of the stack at step 52. In step 54, the topmost blank is lifted by, for example, an end effector. In step 56, the magnetic field generator is activated such that eddy currents and magnetic force vectors (i.e., repulsive forces) directed in the direction of gravity away from the topmost blank 23 are generated. In one form, the direction of gravity is between 90 degrees and 75 degrees as measured from the front face of the blank and as shown in fig. 2 and 3. Thus, in step 58, the unwanted blank adhered to the topmost blank 23 is moved away from the topmost blank 23 in the direction of gravity. Simultaneously and optionally, air may be injected into the stack as the individual blanks are separated by the repulsive force created by the vortex. Finally, in step 60, the topmost blank 23 separated from the stack is moved to a subsequent manufacturing operation, which may be performed by the robot 12 shown in fig. 1.

The blank 22 may be any electrically conductive material that can induce eddy currents, such as aluminum alloys and steel alloys. In one mass automotive production format, the width of the blanks is between about 25mm and about 3000mm, the length of the blanks is between about 25mm and about 300mm, the thickness of each blank is between about 0.5mm and about 6.0mm, and the height of the stack of blanks is between about 6mm and about 2000 mm.

the apparatus and method of the present disclosure are intended to eliminate the need for compressed air, dimple patterns, or other typical methods that facilitate separating the blank in a stamping or other operation.

The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the gist of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.

According to one embodiment of the invention, the transfer mechanism comprises a plurality of suction cups configured to hold the topmost blank of the stack.

According to one embodiment of the invention, the transfer mechanism comprises a robot having an end effector for holding the stack of blanks.

According to one embodiment of the present invention, the above-described invention is further characterized by a controller configured to transmit a signal to the fixture to cause translational movement thereof.

According to one embodiment of the present invention, the above invention is further characterized by a position sensor in communication with the controller for transmitting the position of the clamp to the controller.

According to one embodiment of the invention, the vortex generates a force vector in a direction between 90 degrees and 75 degrees as measured from the forward face of the blank.