WO2004086838A1

WO2004086838A1 - System and method of securing feeder mechanisms

Info

Publication number: WO2004086838A1
Application number: PCT/IB2004/050325
Authority: WO
Inventors: Michael T. Swab
Original assignee: Assembleon N.V.
Priority date: 2003-03-28
Filing date: 2004-03-24
Publication date: 2004-10-07

Abstract

The present invention provides a system and method that secures feeders mechanisms to SMTs. This system includes pneumatic or hydraulically driven cylinder(s) that positions a clamping plate to secure feeder mechanism to the feeder plate thus preventing relative motion between the feeder mechanism and the SMT.

Description

System and method of securing feeder mechanisms

The present invention relates generally to feeder mechanisms and surface mount machines, and more particularly, to a system and method for properly securing feeder mechanisms to their associated feeder plate mechanism or surface mount machines.

Fully automated surface mount assembly machines populate printed circuit boards (PCB) with various components. These tools dramatically raise the productivity in component assembly and lower the cost of production. Each tool is typically designed to work with specific conventional feeders (feeder mechanisms). These feeder types may include bulk, tape, tube, and other like configurations. Tape mechanisms allow surface mount assembly machines to sequentially index carrier tape that contains surface mount electronic components within uniformly spaced cavities. Furthermore, these feeder mechanisms present the components consistently and repeatedly at a proscribed "dead spot" (a/k/a pick point) for pickup by a pickup head and subsequent assembly placement by the surface mount machine.

Currently, carrier tape packaging with small surface mount components therein feeds through the tape feeder to the surface mount machine that picks up the component at the designated pick point and places the surface mount component on the PCB. A principal disadvantage associated with conventional tape feeders, is that these feeder mechanisms are each mechanically secured to the surface mount machines (SMT) or a feeder plate mechanism. This requires operators to individually latch and unlatch each feeder mechanism in order to install or remove the feeder mechanism. Additionally, to prevent miss- processing, a second operator verifies the security of each feeder latch.

Another solution has been to secure feeder mechanisms by manually passing a locking bar through the feeders. However, this is both difficult and cumbersome.

It is therefore highly desirable to have a very efficient and very effective means of automatically securing feeder mechanisms to various SMTs or feeder plate assemblies thereby eliminating the potential for miss-processing that damages small components contained within the feeder mechanism, and operator verification.

The present invention provides a system and method of automatically securing feeder mechanisms to surface mount assembly tools that substantially eliminates or reduces disadvantages and problems associated with previously-developed solutions. More specifically, the present invention provides a pneumatic latching system that secures feeders mechanisms to the surface mount machines. This pneumatic latching system utilizes a hydraulic or pneumatic cylinder to actuate a clamping lever. When activated, the cylinder repositions the lever to toggle a clamping plate into a locked or secured position. This clamping plate exerts sufficient force such that the feeder mechanisms remain locked in position and immobile until the clamping plate is released.

The present invention provides a significant advantage by allowing feeders mechanisms to be automatically secured to surface mount machines with the selection of a switch. Further, an interlock can be incorporated such that the feeder mechanisms cannot feed the SMT until the clamping plate has secured the feeder mechanisms. Additionally, the need for operator verification may be removed, while still reducing the chance of operator error and manpower requirements.

Further novel features and other objects of the present invention will become apparent from the following detailed description, discussion and the appended claims, taken in conjunction with the drawings.

For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings in which like reference numerals indicate like features and wherein:

Fig. 1 shows a perspective view of a FES cart;

Fig. 2 provides a top down view of a feeder plate assembly;

Fig. 3 provides a side view of a feeder plate assembly with an installed feeder mechanism;

Fig. 4 provides a view of external connections from the feeder plate assembly to an SMT;

Fig. 5 provides a perspective view of a generic feeder mechanism; and Fig. 6 depicts the hinged lever that toggles to secure a clamping plate to the feeder mechanism.

Preferred embodiments of the present invention are illustrated in the figures, like numerals being used to refer to like and corresponding parts of the various drawings. The present invention provides a system and method for automatically latching or securing feeder mechanisms to a surface mount machine. This system utilizes hydraulic or pneumatic cylinders in such a way that all associated feeder mechanisms are easily and automatically secured. The present invention utilizes a hydraulic or pneumatic cylinder to reposition a clamping lever. When activated, the cylinder toggles the clamping plate into a locked position. This is done with sufficient force to press all feeder mechanisms to a locked and secured position. When the clamping plate is released, the feeders will be unlocked and may be easily removed.

The present invention allows an individual operator to quickly and easily latch and unlatch a series of feeder mechanisms with the mere press of a button. Thus, the operator can install and remove each feeder mechanism with ease. By automatically securing the feeder mechanisms to the SMT, an electrical or mechanical interlock can assure that the feeder mechanisms are properly mounted, aligned and secured before installing components from the feeder mechanism. Thus, the present invention prevents costly operator errors associated with miss-processing or miss-preparation of the feeder mechanism to the SMT. Additionally, manpower is reduced because the complicated and often difficult manual latching and securing procedure is removed, as well as the need for a second operator verification prior to feeding components from the feeder mechanisms to the SMT.

The present invention may be utilized within a feeder exchange system (FES) that comprises a feeder exchange cart, trolley, or other interfacing device designed to provide seamless integration of feeders to surface mount machines.

A single operator can quickly secure feeder mechanisms to an FES cart or feeder plate assembly and insert or couple these feeders onto a particular SMT.

Figure 1 provides a perspective view of a FES cart that may utilize the latching system provided by the present invention. FES cart 10 includes feeder plate assembly 12 which may contain a number of feeder mechanisms. The feeder plate within this assembly is better illustrated in figure 2.

Figure 2 depicts feeder plate having a pneumatic or hydraulically driven latching mechanism used to secure a feeder mechanism. Feeder plate 14 has a number of grooves 16 in which the individual feeder mechanisms may slide horizontally. Figure 3 provides a side view of feeder plate 14 with a feeder mechanism 18 installed. As shown, feeder mechanism 18 is secured by a feeder bar 20, which receives notch 22 at the nose of feeder mechanism 18. Additionally, a plurality of guide pins or other like mechanisms known to those skilled in the art may be used to align feeder mechanism 18 onto feeder plate 14. When the nose of feeder mechanism 18 receives feeder bar 20, cylinder 24 may toggle lever 26. Lever 26 toggles about hinge 28. When cylinder 24 is in the extended position, clamping plate 30 further secures feeder mechanism 18 to feeder plate 14 at tab 32.

Although this embodiment may utilize tape feeder mechanisms, the present invention may be applied equally to tape, bulk, tube or other such feeder mechanisms as are known to those skilled in the art. Returning to figure 1, the feeder plate may contains up to 20 8mm tape feeders. Tape dump box 34 collects tape waste from feeders mechanisms 18. This waste passes through holes 36 within feeder plate 14 as shown in figure 2.

Feeder plates permit multiple feeder mechanisms to be coupled to the feeder plate. Additionally, feeder plates provide multiple umbilical connections to support the individual feeder mechanisms. These connections include pneumatic, hydraulic, electrical, mechanical, push rod, optical or other like methods of interfacing the feeder mechanisms as is known to those skilled in the art.

Feeder plate assembly 13 shown in figure 2 is a 20-feeder plate that may include internal power/electrical connections and pneumatic or hydraulic connections. Groove 36 allows the necessary hydraulic, pneumatic or electrical connections to operate cylinders 24. Besides internal feeder connections, feeder plate assembly 13 interfaces to the SMT. Surface mount interface 38, shown on the right and the left edges of feeder plate assembly 13 and is illustrated further in figure 4. Here, feeder plate assembly 13 clearly depicts external connections that include positioning pins 40 that guide and align the connection between the SMT and feeder assembly 13, air or pneumatic connections 42, and electrical connections 44. It should be noted that the specifics associated with the feeder plate assembly 13 depend on feeder mechanisms utilized with an intended SMT. Although, the pneumatics are specifically discussed above, the present invention may contemplate the use of hydraulics, air or electric driven motors, or solenoids to operate or reposition the cylinders/clamping plate.

Clamping plate 30 secures a number of feeder mechanisms 18 within the feeder plate assembly 13 by insuring that all feeder mechanisms are properly aligned and secured to feeder plate 14 with equal force. By aligning and securing feeder mechanisms as taught in this disclosure, one avoids misaligning feeder mechanisms, which could result in lost production time and damaged product from the feeder mechanisms or surface mount tool.

Forward motion of the feeder mechanism 18 is prevented by feeder bar 20, which receives notch 22 at the nose of feeder mechanism 18. This bar 20 also helps to prevent up and down motion of feeder mechanism 18 relative to feeder plate 14. Clamping plate 30 prevents backwards-horizontal motion relative to the feeder plate assembly. A notch in tab 32 receives dowel 34 that extends from feeder plate 14 and further prevents vertical motion of feeder mechanism 18 relative to feeder plate 14. Grooves 16 within feeder plate 14 prevent side-to-side motion of feeder mechanism 18. Therefore, the present invention eliminates relative motion and securely locks feeder mechanisms in place when mounted to the SMT.

The present invention thus prevents unnecessary down time and miss- processing associated with improperly assembled equipment. Furthermore, an electrical or mechanical interlock may actually prevent operation of the integrated feeder mechanisms and SMT unless the clamping plate has been activated to secure the feeder mechanisms in place relative to the SMT.

Figure 5 illustrates a perspective view of an interchangeable feeder mechanism 60 used in conjunction with various surface mount machines. The feeder is used for feeding a conventional carrier tape 62 with indexed pockets 64 that contain small components used in conjunction with various conventional pick and place assembly machines for surface mounting of small components onto printed circuit boards. The carrier tape 62 is wound upon reel 66.

Figure 6 provides a cross-sectional view of lever 26 toggled by cylinder 24 in further detail. As shown, lever 26 hingedly mounts to fulcrum 68 by hinge 70. As cylinder 24 drives lever 26 forward, lever 26 rotates counterclockwise to allow clamping plate 30 to engage tab 32 on feeder mechanism 18. Further, if present, dowel 70 engages a notch within the tabbed portion of feeder mechanism 18 to further secure and prevent relative motion of the feeder mechanism when clamping plate 30 has been locked in place. Lever 26 rotates counterclockwise to disengage clamping plate 30 from feeder mechanism 18.

The present invention provides a significant advantage by allowing the owner of a SMT to reduce manpower requirements while still reducing miss-processing through operator error. This is accomplished by ensuring feeder mechanisms are secured to the feeder plate. In fact, mechanical or electrical interlocks may prevent miss-processing while eliminating the need for second operator verification.

In summary, the present invention provides a system and method that secures feeders mechanisms to SMTs. This system includes pneumatic or hydraulically driven cylinder(s) that positions a clamping plate to secure feeder mechanism to the feeder plate. Although the present invention is described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the invention as described by the appended claims.

Claims

CLAIMS:

1. A system that secures feeders mechanisms (18) to feeder plate assemblies (13), comprising: a feeder plate (14) operable to receive a plurality of feeder mechanisms, wherein said feeder mechanism (18) has a tabbed surface; a pneumatic cylinder (24) mounted on said feeder plate (14), wherein said cylinder (24) is operable to toggle a lever (26); and a clamping plate (30), wherein said clamping plate (30) firmly secures said tabbed surface of said feeder mechanism when toggled into a locked position by said lever (26).

2. The system of Claim 1, wherein said feeder plate assembly (13) further comprises a feeder bar (20) operable to receive a notch (22) located on said feeder mechanism (18), and wherein said feeder bar (20) prevents further horizontal motion of said feeder mechanism relative to said feeder plate assembly (13).

3. The system of Claim 1, wherein said tabbed surface of said feeder mechanism receives guide pins which prevent horizontal and vertical motion of said feeder mechanism (18) relative to said feeder plate assembly (13).

4. The system of Claim 1 , wherein said feeder plate assembly (13) couples to a surface mount machine.

5. The system of Claim 4, further comprising an interlock to prevent operation of said surface mount machine unless said clamping plate (30) has been toggled into a locked position by said lever (26).