The present invention relates to face plates used in rack-type electronic modular assemblies of the type used in telecommunications equipment, and more particularly, methods for casting face plates using removable inserts to thus create multiple variations of basic face plate designs without having to recreate full die pieces for each variation.
In certain types of communications and/or computer systems it is common to employ modular, electrical components which are adapted to be carried by a rack or other retaining structure. On the front side of the rack or retaining structure, the components are accessible by technicians for replacement, removal, and/or repair.
The modular components typically include a face plate which protects sensitive electrical features of the component, including circuits, transistors, processors, etc. The face plate may include physical features that aid in the mounting of the component to the rack or retaining structure. These features are typically provided on the upper and/or lower ends of the face plate.
The front surface of the face plate typically includes indicator lights employing LEDs or other means that signal power on/off, system functions etc., and may further include connector ports for connecting, for example, optical fiber cables to the electronic components.
Face plates may be made by die casting metal, or by stamping metal, or by other means. Die casting is desirable because of the complexity of the design and the quality of the finished product and the elimination of subsequent processing steps that are typically required to finish a metal stamping.
While die casting is a preferred method for forming face plates, the advantages can be diminished by cost and time-to-production issues necessitated by the need for slight variations in face plates. For example, a particular design of a face plate may require tens of thousands of dollars to design and build the tooling necessary to make the die castings. If that design employed a single connector port for an optical fiber connector, and it became necessary to have a two port connector face plate, a new set of tooling would have to be commissioned at relatively high cost and with inevitable time delays.
The present invention solves the aforementioned problems by providing a method of making face plates and other die cast electrical components by employing a flexible casting system in which multiple variations of a basic design can be manufactured using the same basic casting tools.
The flexible casting system includes a first major die portion or mold base, a second major die portion or main face plate insert which mates with the first major die portion to form a base tool cavity contoured to form a substantial portion of a casting, and at least one sub-insert removably positioned in the mold cavity to direct material flowing into the mold cavity to form a specific feature.
Preferably, the system employs multiple sub-inserts to provide, for example, multiple variations of a basic face plate design. The variations include face plates with no connector ports, one connector port, two connector ports, and so on. Other face plate variations include no apertures for indicator lights, switches, etc., one aperture, two apertures, and so on.
The sub-inserts can be made with relative ease, and employed in a basic set of casting tools which are relatively more difficult to manufacture. Thus, the advantages of the present invention include reduced time to manufacture, by avoiding having to duplicate basic tool components. Moreover, a cost savings can be realized by not having to duplicate relatively expensive toolings.
Many of the advantages and feature of the present invention will become more apparent in view of the following detailed description and drawings.
Each face plate has in common most physical features and dimensions including (with reference to
The upper and lower ends of each face plate 10(A) through 10(D) include mounting features that allow secure connection of the face plate and associated components to an associated mounting structure. These mounting features include (again, with reference to
It will become apparent from examining the front surface 12 of each face plate 10(A) through 10(D) that there are slight differences between them. For example, the front surface 12 of face plate 10(A) has no openings nor any features of any kind. In essence, the front surface of face plate 10(A) is smooth, planar, and free of openings, indentations, or other features.
In contrast, the face plate 10(B) includes on its front surface two apertures or holes 20 and 22 located at or near the upper end of the face plate. These openings are accompanied by some text, acronyms or other writing to indicate to a technician what the openings are for. By way of example, the openings may be adapted to receive LED's or other light emitting devices or other indicator means that are powered from the electronics on the opposite side of the face plate. These are basically indicator lights to; for example, indicate a system failure, power on/off, state of operations, etc. Depending on the system purchased by a particular customer, or on the features of the system, a system may typically employ several types of face plates, depending on the constituent electronics carried by the face plate. Thus, a system may employ both the face plate 10(A) and 10(B), side-by-side, or otherwise disposed in the same rack or mounting structure.
Referring to
The various apertures may have similar or the same indications at the same locations. Thus, apertures 20, 24, and 32, which preferably are located at the same position on the front surface of each corresponding face plate, may each received the same type of indicator light, such as system on/off, so that the technician can, at a glance at multiple side-by-side face plates, determine that all, some or none are functioning.
While this may be an advantage, it is not necessary to have the apertures in the same place for the same indication. Moreover, the location and number of apertures is intended to show examples, not limitations, as to locations, numbers and variations. For example, the front surface of each face plate could include any number of apertures at any of a variety of locations in a variety of spatial relations to each other.
FIGS. 2(A) through 2(D) are similar to the face plates of FIGS. 1(A) through 1(D). However, in the
It should be noted that the face plates described herein are specifically designed for use in SONET or other optical communications equipment, but the invention is not limited to such uses. Face plates for other equipment, and other structures confronting similar, related or analogous problems can be formed using the inventive techniques and structures described herein.
The access port 40 is an opening formed in a chevron-patterned portion of the front surface 42. When the face plate 34(A) is in use, it is substantially vertically oriented. Thus, it is preferable that the port 40 is formed in the inwardly sloping surface 40(A) of the chevron patterned front surface 42. This has the desired effect of causing the corresponding coupler to orient itself in a downwardly extending position, thus providing some protection from accidental removal, disconnection, or damage.
Accept for the chevron-patterned front surface, the face plate 34(A) is preferably in all other aspects identical to the face plates of the
Likewise, face plate 34(B) differs from face plate 34(A) in only slight ways. Indicator light apertures 44 and 46 are disposed at the same location and indicate the same things as apertures 36 and 38, respectively. Moreover, an access port 48 is located in the same location as access port 40 of the face plate 34(A). However, in the face plate of
Referring to
Referring to
As is apparent from the foregoing descriptions, it is possible to build optical systems in which multiple face plates are employed, with each having relatively slight differences from one to the next. In the manufacturing of these face plates, it has been in the past required to supply a new die set to cast each different face plate, no matter how slight the variations. Die sets are generally expensive and time consuming to manufacture.
Referring now to
As it is preferred to make the face plates by die casting, the material is preferably molten metal, such as aluminum or aluminum based alloys. Other materials could be employed, including thermoplastic and/or thermosetting plastic materials employing injection molding techniques.
As seen in
In the present invention, the mold base 82 includes a rectangular recess 84, which shall hold the cavity main insert when the ejector half 80 is placed together with the mold base 82 and secured together by normal means.
The present invention includes a main insert cavity half 86 and a main insert ejector half 88 which cooperate to define the basic shape of the face plate or final product. When placed together, the main insert cavity half 86 and ejector half 88 form a product-shaped cavity 90. The two halves 86 and 88 fit within the basic cavity 84.
In particular, ejector half 88 will fit into a recess within mold base 80, and cavity half 86 will fit into the recess 84 of mold base 82. Ejector half 92 will fit into a recess in ejector half 88, which as noted, will fit into a recess in mold base 80.
To form the chevron-shaped front surface shown in the embodiments of the series shown in
To illustrate this, reference is made to
In order to form one or more of the access ports, it will be necessary to have opposing surfaces of the two components 92 and 94 touch in an area predetermined to define the size and shape of the port. This can be done by making formations, or protruding lands, on the sub-inserts, or by providing further inserts, such as insert 98 shown in
If it is desired to have a flat front surface, the sub-inserts may include simply a number of smaller inserts such as sub-insert 100 of
For example, the sub-insert 100 of
In any event, inserts such as insert 98, or other surface formations provided on mating sub-inserts, could be used to form the ports on front surfaces with or without apertures.
By using sub-inserts, the present invention allows the manufacture of a wide variety of face plates and other objects without having to replace the relatively expensive and bulky base molds. The system described herein allows for flexibility in the manufacture of a product that may require slight variation from one to the other without having to invest relatively large amounts of capital and time in the development of new molds.
The method of making a face plate according to the present invention can be described as a method which uses successively and selectively inserts within a basic mold base. The basic or primary cavity 84 is formed in the base mold, which itself is made when the ejector half 80 is juxtaposed the cavity half 82. A first cavity portion 90 is formed in a main insert which is formed when the ejector half 88 is juxtaposed the cavity half 86. The first cavity portion 90 has a shape substantially corresponding to an overall size and shape of the face plate. A second cavity portion is formed by juxtaposing the sub-insert ejector half 92 and the sub-insert cavity half 94. The second cavity portion has a shape substantially corresponding to a particular feature of the face plate, such as the chevron-shaped front surface.
To form a face plate, the sub-insert is placed within the main insert, and the main insert is placed within the base cavity, thus completely forming a face plate cavity. The face plate cavity is then filled with material, such as molten metal material, as is normally done in die castings. Then, a molded face plate is removed from the face plate cavity once the material has sufficiently cooled, by separating the ejector half 80 from the cavity half 82. After molding, elements 92 and 88 will remain within ejector half 80, and elements 94 and 86 will remain within cavity half 82. Elements 88, 92, 94, and 86 are only removed from halves 80 and 82 to make different face plate features.
From the foregoing it is believed that those skilled in the pertinent art will recognize that while the invention has been described in association with a preferred embodiment thereof, numerous modifications, changes and substitution of equivalents may be made therein without departing from the spirit and scope of this invention which is intended to be unlimited by the foregoing descriptions of a preferred embodiment except as may appear from the following claims.