Clinching mechanism for assembling electronic components onto printed circuit boards

Abstract

To provide a clinch mechanism in which an electronic component is not damaged by a cut and clinch process.SOLUTION: A clinch mechanism for assembling electronic components on a printed circuit board 100 includes a drive shaft 102 configured to move along a vertical axis Z, a stationary anvil 104 configured to remain stationary while the drive shaft moves, a cutter 106 with a cutting tip 112, and a toggle configured to rotate around a toggle axis of rotation, including involute gear-shaped teeth configured to roll a cutter's involute trapezoidal slot and give the cutter movement against the stationary anvil, the movement of the drive shaft along the linear axis moves the cutter relative to the stationary anvil, moves the cutting tip across the stationary anvil to cut an electronic lead positioned between the cutting tip and the stationary anvil, and to rotate the toggle around the axis.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] This application claims priority to U.S. Provisional Patent Application No. 62 / 861,469, entitled “Improved Cut / Clinch Mechanism for Radial Electronic Component Insertion Machine,” filed June 14, 2019, the disclosure of which is incorporated herein by reference.

[0002] The present invention relates to a clinching mechanism for assembling electronic components to a printed circuit board, and more particularly, to a clinching mechanism for severing the leads of an electronic component after it has been inserted into a printed circuit board. [Background technology]

[0003] When assembling electronic components onto a printed circuit board (PCB), a radial lead insertion machine inserts the component leads of the electronic components into holes in the PCB and, in the same motion, into openings between the cutter and anvil parts of the clinching mechanism underneath the PCB. The cutter is the working part that moves to create the cutting action, and the anvil is the stationary part against which the cutter's movement during cutting presses the leads. The cutter continues the pressing action after the anvil has moved the bottom of the lead, causing the lead to bend up and hit the bottom of the PCB. The clinching mechanism thus cuts the leads protruding from the bottom of the PCB to the desired length and then bends or clinches them close to the bottom of the PCB to hold the component in place until the PCB is wave soldered or the component is soldered in place manually or by an automatic selective soldering machine. The desired outcome of the clinching process is short leads that are bent snugly close to the bottom of the PCB.

[0004] For example, prior art clinching mechanisms are driven by vertical linear motion generated by air cylinders or cam / servo mechanisms. This vertical motion moves a cutter, either directly or via a toggle arm, towards and over an anvil while the leads are cut and the leads are bent to create a clinch on the part. Prior art clinching mechanisms connect the vertical motion to the toggle and to the cutter with pins that slide on flat steel surfaces or with cylindrically shaped parts, which causes unnecessary wear on these parts. In some configurations, prior art clinching mechanisms move the cutter parallel to the bottom of the PCB, which causes high forces on the leads during the cutting and clinching process. Often the cutter and anvil parts are finely machined and ground from hardened steel, making replacement of these wearable parts expensive.

[0005] One drawback of using round pins that slide on a flat surface is that such an arrangement creates excessive wear, requiring frequent replacement of these parts. Cutter parts, which are machined from hardened tool steel and ground on all sides, are expensive to manufacture.

[0006] Another drawback of some prior art clinching mechanisms is the horizontal movement of the cutter on the anvil. During the cutting phase, the leads are held taut between the cutter and the anvil. As the cutter continues its horizontal movement, it exerts strong tensile forces on the leads and, therefore, on the connections between the leads and the electronic components on the PCB. Depending on the combination of lead material, thickness and type of connection to the electronic components, these forces can become unacceptably high and the electronic components can be damaged by the cut-and-clinch process.

[0007] Therefore, an improved clinching mechanism for assembling electronic components to printed circuit boards would be well received in the art. Summary of the Invention

[0008] In one embodiment, a clinching mechanism for assembling electronic components on a printed circuit board comprises a drive shaft configured to move along a vertical axis, a stationary anvil configured to remain stationary while the drive shaft moves, a cutter having a cutting tip, where movement of the drive shaft along a linear axis is configured to move the cutter relative to the stationary anvil and movement of the cutter by the drive shaft is configured to move the cutting tip across the stationary anvil to sever electronic leads positioned between the cutting tip and the stationary anvil, and a toggle configured to rotate about a toggle rotation axis, where movement of the drive shaft along the vertical axis is configured to rotate the toggle about the axis, the toggle including a contact portion configured to roll over an engagement portion of the cutter to impart movement to the cutter relative to the stationary anvil, the contact portion of the toggle including involute gear shaped teeth and the contact portion of the cutter including an involute trapezoidal slot.

[0009] Alternatively, or additionally, the teeth of the involute gear profile are configured to roll in an involute trapezoidal slot in the cutter to impart motion to the cutter relative to the stationary anvil without the slide pin extending through the toggle and cutter.

[0010] Alternatively, or additionally, the cutter and stationary anvil are each machined from a flat plate.

[0011] Alternatively, or additionally, the clinching mechanism further comprises a plurality of cutters and a corresponding plurality of stationary anvils, and movement of the drive shaft along the linear axis is configured to simultaneously move each of the plurality of cutters relative to the corresponding stationary anvil.

[0012] Alternatively, or in addition, the plurality of cutters and the corresponding plurality of stationary anvils comprise a first stack and a second stack, each of the first stack and the second stack including at least one of the plurality of cutters and at least one of the corresponding plurality of stationary anvils.

[0013] Alternatively, or additionally, the cutter is configured to move linearly along an axis that is not orthogonal to the vertical axis.

[0014] Alternatively, or additionally, the clinch mechanism further includes a link rotatably attached to and extending between each of the drive shaft and the toggle, the drive shaft including a first pin, the link configured to rotate about the first pin when the drive shaft moves along the vertical axis, and a second pin extending through each of the toggle and the link, the toggle and the link configured to rotate about the second pin.

[0015] Alternatively, or additionally, the toggle is configured to rotate about a fixed pin aligned with the toggle rotation axis, and the toggle is further configured to rotate about a second pin, the second pin configured to rotate about the fixed pin as the drive shaft moves along the vertical axis.

[0016] Alternatively, or additionally, the first pin is not configured to slide relative to the link.

[0017] In another embodiment, an assembly machine includes a board handling system configured to move a printed circuit board through the assembly machine, one or more assembly heads configured to pick and place components onto the printed circuit board, a clinching mechanism, the clinching mechanism including a drive shaft configured to move along a vertical axis, a stationary anvil configured to remain stationary while the drive shaft moves, and a cutter having a cutting tip, wherein movement of the drive shaft along a linear axis is configured to move the cutter relative to the stationary anvil, and movement of the cutter by the drive shaft moves the cutting tip. and a clinching mechanism including a cutter configured to move across the stationary anvil to cut an electronic lead positioned between the cutting tip and the stationary anvil, and a toggle configured to rotate about a toggle rotation axis, wherein movement of the drive shaft along a vertical axis is configured to rotate the toggle about the axis, and the toggle includes a contact portion configured to roll over an engaging portion of the cutter to impart movement to the cutter relative to the stationary anvil, the contact portion of the toggle including involute gear shaped teeth, and the contact portion of the cutter including an involute trapezoidal slot.

[0018] In another embodiment, a method of assembling electronic components to a printed circuit board includes receiving at least one component lead with a clinch mechanism between a cutter and a stationary anvil of the clinch mechanism; moving a drive shaft of the clinch mechanism along a vertical axis; rotating a toggle about a toggle axis of rotation with the movement of the drive shaft; causing a contact portion of the toggle to roll over a contact portion of the cutter as a result of the rotation of the toggle, the contact portion of the toggle including involute gear shaped teeth and the contact portion of the cutter including an involute trapezoidal slot; imparting motion to the cutter relative to the stationary anvil with the contact portion of the toggle; and severing the at least one component lead by moving a cutting tip of the cutter over the stationary anvil.

[0019] Alternatively, or additionally, the method further includes inserting, with a radial lead insertion machine, at least one component lead of the electronic component into at least one hole in the printed circuit board positioned above the clinching mechanism.

[0020] Alternatively, or additionally, the method further includes bending at least one severed component lead against the printed circuit board with the cutter.

[0021] Alternatively or additionally, the method further includes rolling an involute trapezoidal slot in the cutter with teeth of an involute gear profile on the toggle, and causing the teeth of the involute gear profile on the toggle to impart motion to the cutter relative to a stationary anvil without the slide pin extending through the toggle and cutter.

[0022] Alternatively, or additionally, the cutter and stationary anvil are each machined from a flat plate.

[0023] Alternatively, or additionally, the clinching mechanism includes a plurality of cutters and a corresponding plurality of stationary anvils, and movement of the drive shaft along the vertical axis simultaneously moves each of the plurality of cutters relative to a corresponding stationary anvil.

[0024] Alternatively, or additionally, the method further includes linearly moving the cutter along an axis that is not orthogonal to the vertical axis.

[0025] Additionally or alternatively, the method further includes rotating a link attached to and extending between each of the drive shaft and the toggle, via vertical movement of the drive shaft, the drive shaft including a first pin, the link configured to rotate about the first pin as the drive shaft moves along the vertical axis, and a second pin extending through each of the toggle and the link, the toggle and the link configured to rotate about the second pin; rotating the toggle, via vertical movement of the drive shaft, about a fixed pin aligned with the toggle rotation axis; and rotating the toggle, via vertical movement of the drive shaft, about the second pin such that the second pin is rotated about the fixed pin.

[0026] Alternatively, or additionally, the first pin is not configured to slide relative to the link.

[0027] Alternatively, or additionally, the method further includes bending at least one component lead against the bottom of the printed circuit board with a cutter. [Brief description of the drawings]

[0028] The above, and further advantages, of the present invention may be better understood by referring to the following description in conjunction with the accompanying drawings, in which like reference numerals indicate like elements and features. For clarity, every element may not be numbered in every drawing. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. [Figure 1] FIG. 1 is a perspective view showing an example of a clinching mechanism according to the prior art. [Diagram 2] FIG. 1 is a perspective view showing a first side of a clinching mechanism for assembling electronic components to a printed circuit board having four sets of one cutter and one anvil, according to one embodiment. [Diagram 3] 3 is a side view showing a second side of the clinching mechanism of FIG. 2 with the cutter in an open position according to an embodiment. [Figure 4] FIG. 4 is a side view showing a second side of the clinching mechanism of FIGS. 2-3, with the cutter in a closed position, according to one embodiment. [Diagram 5] FIG. 5 is a perspective view showing a second side of the clinching mechanism of FIGS. 2-4 according to an embodiment. [Figure 6A] 5A is an enlarged view of the portion enclosed by circle A in FIG. 5, showing a partial view of the anvil cutting edge and cutter edge of the clinching mechanism of FIGS. 2-4, according to one embodiment. FIG. [Figure 6B] 5A , showing an enlarged view of the portion enclosed by circle B in FIG. 5 , and a partial perspective view of the toggle tooth profile of the clinching mechanism of FIGS. 2-5A , according to one embodiment. [Figure 7] FIG. 6C is a perspective view of a first side of the clinching mechanism of FIGS. 2-6B with a set of one cutter and one anvil added and electronic leads inserted between each set of one cutter and one anvil according to one embodiment. [Figure 8] 8 is a side view of a first side of the clinching mechanism of FIGS. 2-7 after cutting the electronic leads and bending the electronic leads toward the PCB, according to one embodiment. FIG. [Figure 9] 8 illustrates a PCB assembly machine including the clinching mechanism of FIGS. 2-7 according to embodiments described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] References herein to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the teachings. References herein to a particular embodiment do not necessarily all refer to the same embodiment.

[0030] The present teachings will now be described in more detail with reference to exemplary embodiments thereof as shown in the accompanying drawings. The present teachings will be described in connection with various embodiments and examples, but there is no intent to limit the present teachings to such embodiments. On the contrary, as will be appreciated by those skilled in the art, the present teachings encompass various alternatives, modifications, and equivalents. Those of ordinary skill in the art with access to the teachings herein will recognize additional implementations, modifications, and embodiments within the scope of the disclosure described herein, as well as other fields of application.

[0031] FIG. 1 is a perspective view of an example of a prior art clinching mechanism 10. As shown, the clinching mechanism 10 includes at least one anvil 12 and at least one pivoting cutter 14. Specifically, the prior art clinching mechanism 10 is shown with four anvil / cutter pairs. The cutters 14 are driven by a drive shaft 16, which is configured to move vertically and linearly by an air cylinder (not shown). As shown, the vertical movement of the drive shaft 16 moves the cutters 14 relative to the anvil 12, which remains stationary. When the leads of an electronic component being inserted into a PCB are aligned between the cutter 14 and the anvil 12, the movement of the cutter 14 presses the leads against the anvil 12, and the moving cutter 14 cuts the leads. After cutting, the cutter 14 continues to press against the leads, which are no longer cut, as their lower portions have been cut. This causes the leads to bend up against the bottom of the PCB which, in use, will be positioned directly above the clinching mechanism 10. This clinches the leads near the bottom surface of the PCB downwards and holds the component in place for subsequent process steps until the PCB is wave soldered or the component is otherwise soldered in place either manually or by an automated soldering machine.

[0032] The prior art clinch mechanism 10 is driven by the vertical motion of the drive shaft 16. This vertical motion moves the cutter 14 towards the anvil 12. The prior art clinch mechanism 10 couples the vertical motion to a pin 18, which slides on a flat steel slot 20. This sliding action over time creates unnecessary wear. Furthermore, in the illustrated embodiment, the prior art clinch mechanism 10 moves the cutter 14 parallel to the bottom of the PCB (not shown). This translation of the cutter 14 applies significant forces to the leads during the cutting and clinching process. As illustrated, the cutter 14 and anvil 12 parts are precision machined and ground from hardened steel, making replacement of these wearable parts expensive.

[0033] In the subject matter of the present disclosure relating to the embodiments shown in Figures 2-9, sliding of pins on a plane (as shown by prior art pin 18) is eliminated in the cutter drive mechanism. This is accomplished by adding a link and toggle between the actuator and the moveable cutter. Additionally, whereas the prior art cut / clinch mechanism of Figure 1 includes a pin that slides in a slot to drive the cutter, the new design provides a toggle with teeth in an involute gear configuration. This toothed toggle engages a corresponding involute trapezoidal slot or contact surface in the cutter. This configuration causes the toothed toggle to roll on the surface of the cutter rather than sliding. The embodiments described herein are configured to substantially eliminate part replacement within the cut / clinch mechanism, except due to wear on the actual lead cutting surface.

[0034] Additionally, the novel cut / clinch mechanism design provides a cutter and anvil design that is made from flat material and is simply two-dimensional, simplifying the manufacturing process compared to state-of-the-art parts that are machined and polished on all sides. The plate shape design also allows for simple expansion of the geometry from 5mm tooling (with a stack of three sets of cutters and anvils for inserting electronic components with two or three leads at 2.5mm or 1 / 10" pitch) to 7.5mm tooling (for components with up to four leads) and 10mm tooling (for components with up to five leads) by adding one set of plates and two sets of plates, respectively. The plate design of the tooling not only allows for easy configuration for different types of electronic components, but also reduces the manufacturing cost of the parts.

[0035] By replacing the cylindrical pin sliding on a flat surface with a line contact with a cylindrical pin sliding in a cylindrical link hole, the theoretical contact area is infinitely increased. In the embodiments of the present disclosure, the occurrence of wear and play is significantly reduced. The improvements described herein are configured to reduce the need for expensive replacement parts, especially in the typical case where the equipment is operated 24 hours a day, 7 days a week. Furthermore, wear of parts in the prior art leads to play and the resulting clashing effect when parts engage, making the assembly noisy, requiring frequent adjustments, and degrading the quality of the cut / clinch performance.

[0036] Additionally, prior art cutters move horizontally relative to the drive shaft. Unlike the prior art, the cutter according to the present invention described below moves at a non-perpendicular angle relative to the drive shaft and a non-parallel angle relative to the PCB. This significantly reduces pulling forces on the leads and improves throughput for high precision parts or parts with difficult to cut leads.

[0037] 2 is a perspective view of a first side of a clinching mechanism 100 for assembling electronic components on a printed circuit board having four sets of one cutter and one anvil, according to one embodiment. The clinching mechanism 100 includes a drive shaft 102 configured to move along a vertical axis Z. Shown are four stationary anvils 104a, 104b, 104c, 104d configured to remain stationary while the drive shaft 102 moves. Similarly, shown are four cutters 106a, 106b, 106c, 106d, each configured to move with the movement of the drive shaft 102. Each of the anvils 104a, 104b, 104c, 104d is paired with one of the cutters 106a, 106b, 106c, 106d such that vertical motion by the drive shaft 102 causes movement of the cutter 106a across its respective anvil 104a, movement of the cutter 106b across its respective anvil 104b, movement of the cutter 106c across its respective anvil 104c, and movement of the cutter 106d across its respective anvil 104d. Specifically, these cutters each include a respective cutting tip 112a, 112b, 112c, 112d. Vertical movement by the drive shaft 102 causes the cutting tips 112a, 112b, 112c, 112d to move across the respective tips 114a, 114b, 114c, 114d of the respective stationary anvils 104a, 104b, 104c, 104d.

[0038] The clinching mechanism 100 includes two stacks 108, 110 of cutters and / or anvils. The first stack 108 includes cutters 106a, 106b, 106c and anvil 104d. The second stack 110 includes anvils 104a, 104b, 104c and cutter 106d. Thus, in the illustrated embodiment, the first stack 108 includes three cutters and one anvil, while the second stack 110 includes the opposite, three anvils and one cutter. Other embodiments are contemplated, such as a stack that includes all the cutters and a second stack that includes all the anvils, stacks that each include half the cutters and half the anvils, or the like. In any embodiment, the movement of the drive shaft 102 is configured to cause all of the cutters 106a, 106b, 106c, 106d to move simultaneously relative to the drive shaft 102 while the anvils 104a, 104b, 104c, 104d remain stationary relative to the drive shaft 102.

[0039] The first and second stacks 108, 110 may each be comprised of cutters 106a, 106b, 106c, 106d and anvils 104a, 104b, 104c, 104d machined from a flat plate of solid material. Thus, two-dimensional machining, rather than three-dimensional machining, may be required to machine and finish the flat plates of the stacks 108, 110. The stacks 108, 110 are shown with the individual plates stacked on top of each other. However, very small spaces may be positioned between the individual plates of the cutters 106a, 106b, 106c, 106d and anvils 104a, 104b, 104c, 104d to prevent rubbing, friction, slippage and / or wear of the plate parts.

[0040] The clinch mechanism 100 further includes a first toggle 116a and a second toggle 116b. The toggles 116a, 116b are each configured to rotate about an axis of rotation defined by or aligned with a respective fixed pin 118a, 118b configured to remain stationary relative to movement of the drive shaft 102. The clinch mechanism 100 further includes a first link 120a and a second link 120b. The links 120a, 120b are each rotatably attached to and extend between the drive shaft 102 and the respective toggle 116a, 116b.

[0041] Figure 3 is a side view of a second side of the clinching mechanism 100 of Figure 2 with cutters 106a, 106b, 106c, 106d in an open position, according to one embodiment. Figure 4 is a side view of a second side of the clinching mechanism 100 of Figures 2-3 with cutters 106a, 106b, 106c, 106d in a closed position, according to one embodiment. In the views of Figures 3 and 4, the clinching mechanism 100 has been rotated from the view shown in Figure 2 so that the underside is visible.

[0042] Upward movement of the drive shaft 102 along the vertical axis Z (i.e., movement between Figures 3 and 4) is configured to move the tops of the links 120a, 120b and the bottoms of the toggles 116a, 116b outward. This vertical movement of the drive shaft is configured to rotate the toggle 116a about the fixed pin 118a in a clockwise direction relative to the perspective shown in Figures 3 and 4. Similarly, this vertical movement of the drive shaft is configured to rotate the toggle 116b about the fixed pin 118b in a counterclockwise direction relative to the perspective shown in Figures 3 and 4.

[0043] The toggles 116a, 116b each include a contact portion 122a (shown in FIG. 2), 122b positioned at an upper end of the toggles 116a, 116b. The contact portions 122a, 122b are each configured to roll over an engagement portion 124a (shown in FIG. 2), 124b of each of the cutters 106a, 106b, 106c, 106d without causing sliding friction between the toggles 116a, 116b and the cutters 106a, 106b, 106c, 106d. This rolling pressure is configured to impart movement to the cutters 106a, 106b, 106c, 106d relative to their respective stationary anvils 104a, 104b, 104c, 104d.

[0044] The drive shaft 102 includes a first pin 130 about which the links 120a, 120b are configured to rotate as the drive shaft 102 moves along the vertical axis Z. This movement of the drive shafts 120a, 120b about the first pin 130 is accomplished without a mechanically sliding pin. Thus, the first pin 130 is not configured to slide relative to the links 120a, 120b. Additionally, as shown, a second pin 132a, 132b extends through each of the respective toggles 116a, 116b and links 120a, 120b, and the respective toggles 116a, 116b and links 120a, 120b are configured to rotate about the second pin 132a, 132b. Each of the toggles 116a, 116b is further configured to rotate about its respective second pin 132a, 132b. Each of the second pins 132a, 132b is individually configured to rotate about its respective fixed pin 118a, 118b as the drive shaft 102 moves along the vertical axis Z.

[0045] As shown, the cutters 106a, 106b, 106c, 106d are each configured to move linearly along axis A, which is a non-vertical and non-horizontal path that is not parallel to either the vertical axis Z of the drive shaft or the horizontal PCB that will be positioned above the clinching mechanism 100 in use. Instead, the cutters 106a, 106b, 106c, 106d are configured to move along this angled path defined by axis A via motion along the vertical direction V of the drive shaft 102. The path defined by axis A may be guided by additional pins 134a, 136a for the cutters of the second laminate 110 and additional pins 134b, 136b for the cutters of the first laminate 108. The upper guide pins 134a, 134b are aligned with channels cut into the bottom of each of the cutters 106a, 106b, 106c, 106d so that the cutters can move relative to the guide pins 134a, 134b. Guide plates (not shown) may be fabricated on the cutters 106a, 106b, 106c, 106d to provide additional guidance to retain the movement of the cutters 106a, 106b, 106c, 106d along the axis A. These pins 134a, 134b, 136a, 136b are shown as stationary pins that do not move with the movement of the drive shaft 10. The pins 134a, 134b, 136a, 136b may also be configured to hold the stationary anvils 104a, 104b, 104c, 104d in a stationary position relative to the drive shaft 102. Additionally, additional pins 138a, 138b may be configured to provide stationary support for the base of the anvils 104a, 104b, 104c, 104d.

[0046] FIG. 5 is a perspective view of a second side of the clinching mechanism 100 of FIGS. 2-4, according to an embodiment. The clinching mechanism 100 is shown in an open state before the drive shaft 102 is vertically moved upward. FIG. 6A is an enlarged view of the portion enclosed by circle A in FIG. 5, showing a partial view of the stationary anvils 104c, 104d and cutters 106a, 106b, 106c, 106d of the clinching mechanism 100 of FIGS. 2-4, according to an embodiment. Specifically, the enlarged view shows the tips 114c, 114d of the anvils 104c, 104d and the tips 112c, 112d of the cutters 106c, 106d. Spaces remain between the individual tips 112c, 114c and 112d, 114d to allow for electrical leads to be placed therebetween. Additionally, the cutting tips 112c, 112d are shown at a vertical level below the respective anvil tips 114c, 114d, which allows for the cutter to move at an upward angle along axis A during cutting.

[0047] FIG. 6B is an enlarged view of the portion enclosed by circle B in FIG. 5, showing a partial perspective view of the shape of the toggle 116b of the clinching mechanism 100 of FIGS. 2-6A, according to an embodiment. Specifically, the contact portion 122b of the toggle 116b includes teeth of an involute gear shape. Similarly, the contact portion 124b of the cutter 106d includes an involute trapezoidal slot configured to receive the teeth of the involute gear shape of the contact portion 122 of the toggle 116b. When the toggle 116b is rotated by the vertical motion of the drive shaft 102, the teeth of the involute gear shape of the toggle 116b roll through the involute trapezoidal slot of the cutter 106d, configured to impart the cutter with movement along axis A relative to the respective stationary anvil 104d. This movement is thus produced without a slide pin extending through the cutter 106d and / or the toggle 116b. Although not shown in this view, the toggle 116a also includes a similarly shaped contact portion 122a. Additionally, the contact portions 122a, 122b extend throughout the thickness of the respective stacks 108, 110 for simultaneously moving each of the respective cutters 106a, 106b, 106c, 106d within the stacks 108, 110. Similarly, although only one cutter 106d and its contact portion 124b are shown, the other respective cutters 106a, 106b, 106c also include respective contact portions for receiving the involute gear shaped teeth of the respective toggles 116a, 116b.

[0048] FIG. 7 is a perspective view of a first side of the clinch mechanism 100 of FIGS. 2-6B with an additional set of one cutter and one anvil added and electronic leads 199a, 199b, 199c, 199d, 199e inserted between each set of one cutter and one anvil, according to one embodiment. Here, the clinch mechanism 100 is shown with an additional set of one cutter 106e and one anvil 104e installed. The clinch mechanism 100 shown in FIG. 7 can also be the same mechanism as shown in FIGS. 2-6, but modified to add a set to each of the stacks 108, 110. Thus, the clinch mechanism 100 includes five sets of cutters and anvils installed. The clinch mechanism 100 is shown in an open, pre-cut state with each anvil / cutter set having one of the electronic leads 199a, 199b, 199c, 199d, 199e inserted therebetween. Although not shown, it should be understood that these leads 199a, 199b, 199c, 199d, 199e are part of an electronic component that is inserted via a PCB that is positioned above the clinch mechanism and oriented perpendicular to the vertical axis Z. As shown, the dimensions of the components of the clinch mechanism 100 provide staggered receiving positions for the leads 199a, 199b, 199c, 199d, 199e. Specifically, the receiving positions are staggered in both the X-axis (left / right) and the Y-axis (front / back).

[0049] FIG 8 is a side view of a first side of the clinching mechanism 100 of FIGS. 2-7 after cutting an electronic lead and bending the electronic lead toward a PCB 198, according to one embodiment. As shown, electronic lead 199a is shown cut and bent by cutter 106a after being inserted between cutter 106a and anvil 104a as shown in FIG 7. Electronic lead 199a is further bent by cutter 106a toward the bottom of the PCB. After this bending of electronic lead 199a, cutter 106a is shown beginning to retract to an open position to await the insertion of another electronic lead and the subsequent cutting and bending process.

[0050] FIG. 9 illustrates a PCB assembly machine 200 including the clinch mechanism 100 of FIGS. 2-7 according to an embodiment described herein. The PCB assembly machine 200 is shown including a frame 210 that encloses a board handling system 212 accessible through a first opening 214 and a second opening 216. The PCB assembly machine may receive a PCB through one of the openings 214, 216 and transfer the PCB to a station above the clinch mechanism 100 for placement of electronic components. The PCB assembly machine may include one or more assembly heads configured to pick and place the components from the heads onto the PCB. The assembly machine may be fitted with a feeder system (not shown) for providing electronic components to the heads. Additionally, the PCB assembly machine may include a control system including a programmable user interface 218 configured to control the board processing, the heads and the clinch mechanism 100 according to a suitable PCB assembly process.

[0051] Further described herein is a method of assembling an electronic component on a printed circuit board. The method contemplated herein includes receiving at least one component lead, such as one of the component leads 199, by a clinching mechanism, such as clinching mechanism 100, between a cutter, such as one of the cutters 106a, 106b, 106c, 106d, 106e of the clinching mechanism, and a stationary anvil, such as one of the stationary anvils 104a, 104b, 104c, 104d, 104e. The method may include moving along a vertical axis, such as vertical axis Z, by a drive shaft of the clinching mechanism, such as drive shaft 102. The method may include rotating a toggle, such as one of the toggles 116a, 116b, about a toggle rotation axis, such as an axis aligned with one of the stationary pins 118a, 118b, by moving the drive shaft. The method may further include causing a contact portion of the toggle, such as one of the contact portions 122a, 122b, to roll an engagement portion of the cutter, such as one of the engagement portions 124a, 124b, as a result of rotation of the toggle. The method may include imparting motion to the cutter relative to a stationary anvil with the contact portion of the toggle, and severing at least one component lead by moving a cutting tip, such as one of the cutting tips 112a, 112b, 112c, 112d of the cutter over the stationary anvil.

[0052] Still further, the method may include inserting at least one component lead of the electronic component into at least one hole in the printed circuit board positioned above the clinching mechanism with a radial lead insertion machine, such as PCB assembly machine 200. The method may include bending the severed at least one component lead against the bottom of the printed circuit board with a cutter.

[0053] According to the method described herein, the contact portion of the toggle includes involute gear teeth and the contact portion of the cutter includes involute trapezoidal slots. The method may include rolling the involute trapezoidal slots of the cutter with the involute gear teeth of the toggle, and causing the involute gear teeth of the toggle to impart motion to the cutter relative to a stationary anvil without a sliding pin extending through the toggle and the cutter.

[0054] In accordance with the methods described herein, the cutters and stationary anvils may each be machined from a flat plate, and the clinching mechanism includes a plurality of cutters and a corresponding plurality of stationary anvils such that movement of the drive shaft along a vertical axis simultaneously moves each of the plurality of cutters relative to the corresponding stationary anvil.

[0055] The method may further include linearly moving the cutter along an axis, such as axis A, that is not orthogonal to the vertical axis.

[0056] Still further, the method may include rotating a link, such as one of links 120a, 120b, attached to and extending between each of the drive shaft and the toggle, with vertical movement of the drive shaft. According to the method, the drive shaft may include a first pin, such as coupling pin 130, configured to rotate the link about the first pin when the drive shaft moves along a vertical axis, and a second pin, such as second pin 132a, 132b, extending through each of the toggle and the link, configured to rotate the toggle and the link about the second pin. The first pin may not be configured to slide relative to the link. The method may further include rotating the toggle about a fixed pin, such as stationary pin 118a, 118b, aligned with the toggle axis of rotation, via vertical motion of the drive shaft, and rotating the toggle about a second pin, such that the second pin is rotated about the fixed pin. The method may further include bending at least one component lead against the bottom of the printed circuit board with a cutter.

[0057] Although the present invention has been shown and described with reference to specific embodiments, it should be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as set forth in the appended claims.

Claims

1. 1. A clinching mechanism for assembling electronic components to a printed circuit board, comprising: A drive shaft configured to move along a vertical axis; a stationary anvil configured to remain stationary while the drive shaft moves; a cutter having a cutting tip, wherein movement of the drive shaft along the vertical axis is configured to move the cutter relative to the stationary anvil, and movement of the cutter by the drive shaft is configured to move the cutting tip across the stationary anvil to sever an electronic lead positioned between the cutting tip and the stationary anvil; a toggle configured to rotate about a toggle axis of rotation, wherein movement of the drive shaft along the vertical axis is configured to rotate the toggle about the toggle axis of rotation, the toggle including a contact portion configured to roll along an engagement portion of the cutter to impart movement to the cutter relative to the stationary anvil, the toggle contact portion including involute gear shaped teeth, and the cutter engagement portion including an involute trapezoidal slot; a link rotatably attached to and extending between each of said drive shaft and said toggle; a clinch mechanism including:

2. 2. The clinch mechanism of claim 1, wherein the involute gear teeth are configured to roll along an involute trapezoidal slot in the cutter without a slide pin extending through the toggle and cutter to impart motion to the cutter relative to the stationary anvil.

3. The clinch mechanism of claim 1 , wherein the cutter and the stationary anvil are each machined from a flat plate.

4. 2. The clinching mechanism of claim 1, further comprising a plurality of cutters and a corresponding plurality of stationary anvils, wherein movement of the drive shaft along the vertical axis is configured to simultaneously move each of the plurality of cutters relative to the corresponding stationary anvils.

5. 5. The clinch mechanism of claim 4, wherein the plurality of cutters and the corresponding plurality of stationary anvils comprise a first stack and a second stack, and the first stack and the second stack each include at least one of the plurality of cutters and at least one of the corresponding plurality of stationary anvils.

6. The clinching mechanism of claim 1 , wherein the cutter is configured to move linearly along an axis that is not orthogonal to the vertical axis.

7. 2. The clinch mechanism of claim 1, further comprising a first pin and a second pin, the first pin included in the drive shaft, the link configured to rotate about the first pin when the drive shaft moves along the vertical axis, and the second pin extending through each of the toggle and the link, the toggle and the link configured to rotate about the second pin.

8. 8. The clinch mechanism of claim 7, wherein the toggle is configured to rotate about a fixed pin aligned with the toggle rotation axis, the toggle is further configured to rotate about the second pin, the second pin configured to rotate about the fixed pin as the drive shaft moves along the vertical axis.

9. The clinch mechanism of claim 7 , wherein the first pin is not configured to slide relative to the link.

10. An assembly machine, a board handling system configured to move printed circuit boards within the assembly machine; one or more assembly heads configured to pick and place components onto the printed circuit board; A clinch mechanism comprising: A drive shaft configured to move along a vertical axis; a stationary anvil configured to remain stationary while the drive shaft moves; a cutter having a cutting tip, wherein movement of the drive shaft along the vertical axis is configured to move the cutter relative to the stationary anvil, and movement of the cutter by the drive shaft is configured to move the cutting tip across the stationary anvil to sever an electronic lead positioned between the cutting tip and the stationary anvil; a toggle configured to rotate about a toggle axis of rotation; and Movement of the drive shaft along the vertical axis is configured to rotate the toggle about the toggle axis of rotation, the toggle including a contact portion configured to roll along an engagement portion of the cutter to impart movement to the cutter relative to the stationary anvil, the toggle contact portion including teeth in an involute gear configuration, and the cutter engagement portion including an involute trapezoidal slot; a link rotatably attached to and extending between each of said drive shaft and said toggle; Including the assembly machine.

11. A method for assembling electronic components on a printed circuit board, comprising the steps of: receiving at least one component lead with a clinching mechanism between a cutter and a stationary anvil of the clinching mechanism; a drive shaft of the clinch mechanism moving along a vertical axis; Rotating a toggle about a toggle rotation axis by moving the drive shaft; movement of the drive shaft along the vertical axis to rotate a link rotatably attached to and extending between each of the drive shaft and the toggle; rotation of the toggle results in a contact portion of the toggle rolling along an engagement portion of the cutter, the contact portion of the toggle including teeth of an involute gear configuration and the contact portion of the cutter including an involute trapezoidal slot; a contact portion of the toggle imparting motion to the cutter relative to the stationary anvil; severing the at least one component lead by moving a cutting tip of the cutter across the stationary anvil.

12. 12. The method of claim 11, further comprising inserting, with a radial lead insertion machine, the at least one component lead of an electronic component into at least one hole in a printed circuit board positioned above the clinching mechanism.

13. The method of claim 12 further comprising bending the severed at least one component lead against the printed circuit board with the cutter.

14. rolling along the involute trapezoidal slot of the cutter with the involute gear teeth of the toggle; 12. The method of claim 11, further comprising: teeth on the involute gear configuration of the toggle imparting motion to the cutter relative to the stationary anvil without a slide pin extending through the toggle and cutter.

15. The method of claim 11 , wherein the cutter and the stationary anvil are each machined from a flat plate.

16. The method of claim 11 , wherein the clinching mechanism includes a plurality of cutters and a corresponding plurality of stationary anvils, and movement of the drive shaft along a vertical axis simultaneously moves each of the plurality of cutters relative to the corresponding stationary anvil.

17. The method of claim 11 , further comprising linearly moving the cutter along an axis that is not orthogonal to the normal axis.

18. the clinch mechanism further comprises a first pin and a second pin, the first pin being included in the drive shaft, the link being configured to rotate about the first pin as the drive shaft moves along the vertical axis, and the second pin extending through each of the toggle and the link, the toggle and the link being configured to rotate about the second pin; vertical movement of the drive shaft causes the toggle to rotate about a fixed pin aligned with the toggle axis of rotation; 12. The method of claim 11, further comprising: rotating the toggle about the second pin by vertical movement of the drive shaft such that the second pin is rotated about the fixed pin.

19. The method of claim 18 , wherein the first pin is not configured to slide relative to the link.

20. The method of claim 12 further comprising bending the at least one component lead against a bottom of the printed circuit board with the cutter.

Images