Field of Search:
339/17,18,19,14,75M,75MP,92R,92M,192R,176M,176MP,64-66 317/101
Claims:
What is claimed is
1. A circuit connecting arrangement comprising:
2. A circuit connecting arrangement in accordance with claim 1 wherein said means for aligning comprises a pin guide having a plurality of holes corresponding to the number of said first male pins, said holes having a funnel-shaped entrance passageway in order to receive misaligned first male pins.
3. A circuit connecting arrangement in accordance with claim 1 wherein said female receptacles float within said third connector means for receiving said male pins which may be slightly out of tolerance.
4. A circuit connecting arrangement in accordance with claim 1 wherein respective fourth and fifth connectors having male pins are provided,
5. A circuit connecting arrangement in accordance with claim 1 wherein said means for holding to the chassis comprises a threaded bolt.
6. A circuit connecting arrangement in accordance with claim 5 wherein extension means are connected to said bolt for coupling with a wrench.
7. A circuit connecting arrangement in accordance with claim 6 wherein said wrench comprises a torque wrench.
8. A circuit in accordance with claim 7 wherein locating means are provided on said third connector means for accurately positioning said torque wrench.
Description:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the field of connectors and in particular to the field of electrical circuit interconnections.
2. Description of the Prior Art
The known prior art techniques of providing interconnections between independent modules has utilized either flat cable or twisted pairs. Flat cable and twisted pairs have not proved entirely satisfactory since it is difficult in either arrangement to keep the lead length at a minimum. Extra lead length causes a deterioration of the transmitted signals due to intercoupled noise and cross talk. Cross talk is a serious shortcoming in, for example, a high speed computer installation in view of the small amplitude, high speed signal transfer between modules.
Twisted pairs (a signal lead and a ground lead twisted together) have also not proved satisfactory in view of the difficulty in making disconnects between modules since each twisted pair is connected to a male connector in the module by means of a wire wrap connection. It therefore can be easily recognized that to remove a module from a rack for repair or replacement purposes is a tedious and a time consuming operation.
SUMMARY OF THE INVENTION
The interconnection system disclosed utilizes two separate male connector units, each of which is respectively located in a respective module in a rack-type arrangement. One-to-one interconnections are obtained between the two modules via the connector units which have male pins projecting through both sides thereof. Various connections in the circuit modules are connected to certain ones of the projecting male pins emanating from one side of the connectors. The pins emanating out of the aforementioned male connectors are first aligned by a pin guide after which they are inserted into a female receptacle. The female receptacle includes pins that float within the receptacle for receiving the male pins which may still be out of alignment after being aligned by the pin guide. The pins emanating out of the other side of the male connectors are available as test points.
The one-to-one connection between the two modules is completed by means of a printed circuit board which provides a direct connection between certain pins of one module with certain pins of the second module.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an assembly drawing depicting the arrangement of the various elements of the invention;
FIG. 2 is a top view of the assembly as shown in FIG. 1, and in particular shows the layout of the printed circuit board;
FIG. 3 is a sectional view of FIG. 2;
FIG. 4 illustrates the relationship of the insertion/extraction tool utilized with the inter-module connector;
FIG. 6 is a sectional view of the locking mechanism utilized with the tool of FIG. 4;
FIG. 5 is a top view of the insertion/extraction tool of FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 in greater detail, the overall arrangement of the inter-modular connector system is depicted. The modules 7 and 8 are part of an electronic system such as a computer and contain some of the essential electronics to perform a particular function or operation and are conventionally positioned on a frame part of which is shown by member 70. The operational electronics is contained on the printed circuit (i.e., P.C.) card and there may be a library of such cards arranged in a vertical manner. The purpose of the invention is to interconnect certain pin locations in module 7 which are connected to certain circuits in the printed card 61 to another pin and circuit locations (not shown) at module 8 with a minimum of lead line. It is imperative that interconnecting lead lines be held to a very minimum because of the high speed circuitry utilized in modern day electronic installations. The longer the lead lines the more degraded will be the signal transmission between modules. This degradation of the signal transmission between modules effects the operation and performance of the electronic circuitry.
Projecting through the backside as well as the front side of connectors 10 and 12 are male pins such as pins 15, 17 and 19 which are shown by way of example, projecting through connector 10. The rear projections 10', 10" and 10'" are utilized for test purposes. The pins 15, 17 and 19 also have front projections 4, 5 and 6 coming through connector 10. The front projections emanating from connectors 10 and 12 are longer than the rear projections. The front projections 4, 5 and 6 of the male connector 10 are ohmically connected to a corresponding pin such as 7' of module 7 by way of a wire wrap connection. In this manner the circuits of the P. C. Card 61 are translated to another level of connector hardware. With respect to the front projections, 4, 5 and 6 there may be a mismatch of as much as 21-27 mils (thousandths of an inch) of the pins from one module to the other. This mismatch represents an accumulation of tolerances that result from variations from frame to frame. Since there are as many as 96 pins per male connectors 10 and 12 it can be easily recognized that the large tolerance mismatch would prevent a proper mating with a female type connector. In order to reduce the tolerance mismatch of the pins a pin guide 14 is utilized. The pin guide has a funnel shaped entrance passageway to receive the misaligned pins. This aspect on the invention will be discussed in greater detail when referring to FIG. 3.
Referring now to FIG. 2, there is illustrated the printed circuit board 18 which is positioned on top of the female connector block 16 (see FIG. 1). The printed circuit board 18 is provided with 96 holes in the upper section and 96 holes in the lower section and corresponds to the number of pins extending through the female connector 16 of FIG. 1. The printed circuit card 18 depicts a plurality of connections such as 22 between certain holes of the upper section to certain holes of the lower section. In other words, the connectors provide a one-to-one connection from one of the holes of the upper section to one of the holes in the lower section. It will become readily apparent how inter-connections are made from module 7 to module 8 via the printed circuit card by referring to FIG. 3.
FIG. 3 illustrates a sectional view 3--3 of the upper portion of the connector assembly illustrated in FIGS. 1 and 2. Thus, FIG. 3 shows the male connector 10 with three of the 96 male pins 15, 17 and 19. The male pins are shown having rear projections 10', 10" and 10'" each of which projects through the backside of the connector 10. Projections 4, 5 and 6 are depicted projecting through the front side of the connector. The rear projections 10', 10" and 10'" are utilized to provide test probes for circuit checking purposes. The front projections 4, 5 and 6 are utilized for mating with the female connector 16 via the pin guide 14.
The difficulty in making a positive connection between two 96 male pin connectors in separate modules 7 and 8 with a fixed 192 female pin connector is that the modules cannot be assembled within a tight tolerance range. The reason for this is that the modules are independently part of a large framework such as employed in a computer and as a consequence, there is a large tolerance build-up. Accordingly, the pin guide 14 incorporates a funnel-shaped entrance passageway to allow reception of the male pins 15, 17 and 19 despite a mismatch of as much as 21 - 27 mils from one module to the other. The female connector 16 is shown juxtaposed to the pin guide 14. The female connector 16 houses a plurality of receptacles 21, 23 and 25 which have a female portion at one end and a male extension at the other end. The receptacles 21, 23 and 25 are arranged within the female connector 16 so that they effectively float. The reason that the receptacles float is that the pin guide 14 is not always able to bring the male pin projections 4, 5 and 6 into a perfect alignment. In other words, the pin guide reduces the 21-27 mil mismatch in the male connectors 10 and 12 to within an acceptacle 6 mil tolerance of the female connector 16. Therefore, since the receptacles 21, 23 and 25 are able to float within the connector 16, a misalignment of the above-mentioned tolerance of the male pin projections 4, 5 and 6 will still permit a mating to take place with the female portion of the receptacles 21, 23 and 25.
The printed circuit card 18 is shown juxtaposed to the female connector 16. The male extensions of the receptacles 21, 23 and 25 are long enough to just project through the various holes provided in the printed circuit card 18. Each one of the male extensions of the receptacles 21, 23 and 25 enters one of the 96 holes provided in the printed circuit card 18. By processing the printed circuit card-connector assembly in a wave soldering bath a fillet of solder such as 27 can be provided so as to make a positive ohmic connection from the pin to the respective metallic connection such as connection 27 (see FIG. 3) on the printed circuit card. In other words, it can be seen that a positive interconnection can be made that extends from the male pin projections 4, 5 and 6 all the way to the printed circuit card 18. Accordingly, by means of the interconnecting lines 22 on the printed circuit card 18, a location or connection on the module 7 which is in turn connected to P. C. cards such as 61 can be made to a connection on the module 8 which is also connected to P. C. cards by the most expedient and shortest connection possible. This is a requirement to prevent signal deterioration on transfer of information between module 7 and 8.
Referring again briefly to FIG. 1, it can be seen that the inter-module connector is fixed and located by a bolt 20 which is threaded into a floating nut 30 after passing through the printed circuit card 18, the female connector 16, the pin guide 14, and the U-shaped member 70. The threaded bolt 20 is shown to have two extensions 60 and 71 for purposes that will be explained in greater detail below. The bolt 20 is threaded into the floating nut 30 to hold the entire connecting module in position. In order to prevent an unwarranted tightening of the module into the chassis where excessive torque could cause a cracking and destruction of some portion of the connector, an insertion/extraction tool 50 is utilized as can be seen in greater detail in FIG. 4. This tool is designed such that locating legs 51 and 52 can be positioned on the guides 31 and 32 of the female connector (FIG. 1). The tool 50 is arranged in a manner so that a collar 53 on the tool is adapted to receive the two extensions 60 and 71 on the bolt 20 (FIGS. 1 and 2). The collar 53 is depicted in greater detail in FIG. 6. The tool 50 allows an adjustable torque handle 54 to apply the required twisting force to the bolt 20.