US Patent References:
ConnecterBerndt - December 1936 - 2063718
Description:
FIELD OF THE INVENTION
This invention relates to a power connector and more particularly to a quick connect-disconnect high current, low voltage connector.
BACKGROUND OF THE INVENTION
Quick connect-disconnect power connectors are known in the prior art. They generally consist of a socket or receptacle into which a connector pin is inserted to complete the connection. Usually, some type of force applying mechanism such as a cantilever spring located within the receptacle provides a force against the connector pin so that it makes good frictional contact with at least part of the wall of the receptacle. This type of connector does not utilize its full potential, since contact is made over only a small portion of the available surface area. This is acceptable in most high voltage applications, since the resistance and accompanying voltage drop is small in comparison to the voltage available. However, in low voltage, high current applications such a voltage drop is relatively large and cannot be tolerated.
It is the main object of the present invention to provide a quick connect-disconnect high current, low voltage connector in which the resistance and accompanying voltage drop are minimized.
It is another object of the present invention to provide a quick connect-disconnect power connector in which the full surface area of the connecting pin and socket are utilized without introducing excessive friction and without sacrificing the quick connect-disconnect feature.
It is a further object of the present invention to provide a quick connect-disconnect power connector in which the frictional holding force on the connector pin increases as the force to remove the connector pin from the receptacle increases until the removal operation is initiated.
SUMMARY OF THE INVENTION
A quick connect-disconnect power connector is provided having an elongated housing in which a spiral braid is connected having a tubular form providing an opening therethrough at least at one end thereof. The braid is connected at one end to the housing and is connected at the other end to a variable tension connection means which is interposed between the second end of the spiral braid and the housing. A connector pin is adapted to fit tightly into the opening of the spiral braid so that the insertion force varies the tension on the variable tension means, thereby relieving the tension on the spring braid and causing the tubular form length to diminish and the diameter thereof to enlarge for easier insertion of the connector pin. The spiral braid increases in length and decreases its tubular form diameter, when the spring tension is reapplied between the spring braid and the housing, thereby frictionally grasping the connector pin preventing its removal and providing a multi-contact electrical connection between the spiral braid and the connector pin.
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of an embodiment of the invention as illustrated in the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an end view of the spiral braid connector of this invention.
FIG. 2 is a plan view of the spiral braid connector of this invention.
FIG. 3 is a top view of the spiral braid connector of this invention.
FIG. 4 is a plan view of the spiral braid connector showing the connector pin being inserted into the spiral braid.
FIG. 5 is a plan view showing the pin in position within the spiral braid connector.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION
Referring to FIG. 2, there is shown a spiral braid connector which consists of an elongated housing 10 in which the spiral braid 12 is connected. The housing 10 may be made of plastic or other suitable insulative material. The spiral braid 12 is woven into a tubular form and connected at both ends thereof into the housing 10. The connection 14 at the first or left hand end of FIG. 2 consists of a pair of jaw type clamping members 16a, 16b which clamp the respective end of the tubular form spiral braid therebetween. The clamping of the tubular form spiral braid 12, in this manner, tends to flatten the end of the tubular braid so that it takes a modified conical shape. The clamp type connector 16a, 16b also includes a terminal 18 for completing the electrical connection, for example, to a power bus. The details of the jaw type clamping means 16a, 16b can best be seen in FIG. 1, where simple bolts 19 are shown at each end of the clamp to clamp the two jaw members 16a, 16b together. The right hand or second end of the spiral braid 12 is connected to the second end of the housing 10 through a variable tension arrangement 20. This second end of the spiral braid 12 is held open, in its tubular form, by a connecting member 22 which connects this second end of the spiral braid 12 to a pressure plate 24. The end of the connecting member 22 connected to the second end of the spiral braid 12 consists of a rim over which the spiral braid 12 fits to hold the braid in its open tubular form. The pressure plate 24, to which the other end of the connecting member 22 is connected, is slidably mounted on rods 26 which extend outwardly from the base plate 28 of the housing 10. These rods 26 pass through openings in the pressure plate 24 so that the pressure plate 24 can be moved toward or away from the base plate 28 of the housing 10 by sliding on the rods 26. Each of the rods 26 has a spring 30 mounted between the base plate 28 and the pressure plate 24 so that tension or outward pressure is maintained on the pressure plate 24. This tension is transferred to the spiral braid 12 by the connecting member 22. It should be appreciated, that movement of the pressure plate 24 toward the base plate 28 of the housing increases the tension on the springs 30 but relieves the tension on the spiral braid 12. Similarly, when the pressure plate 24 is at its most extended position away from the base plate 28, the full tension is applied to the spiral braid 12. The pressure plate 24 has an opening 32 therein which is indexed with an opening 34 in the base plate 28 of the housing 10 and the opening in the spiral braid 12. A connector pin 36 is shown in FIGS. 2 and 3 adapted for insertion through the openings in the pressure plate 24 and base plate 28 of the housing into the spiral braid 12. The connector pin 36 has a terminal 38 thereon to which a connecting wire can be crimped or soldered. FIG. 4 shows the pin 36 being inserted into the spiral braid 12, while FIG. 5 shows the pin 36 in position within the braid 12 making maximum surface contact between the pin and the braid for a good low resistance low voltage drop connection therebetween.
The most important feature of the connector is the spiral braid 12 itself. This is formed of strands of flexible material which are woven in spiral form to form a tubular braid 12 of woven material. The actual material used for the strands is tin coated copper, which is sufficiently flexible, and also makes a good electrical connection between the braid 12 and the pin 36. The angle, with respect to the central axis of the tubular form spiral braid 12, at which the individual strand is woven determines the operation of the overall braid. Each strand is spirally woven about the connector pin 36 at a particular angle with respect to the central axis. For example, the largest angle would be 90° with respect to the central axis. This would be winding the strand about a given diameter, that is, with no spiral effect. The other extreme would be weaving the strand with as large a spiral effect as possible, giving the smallest angle with respect to the central axis of the tubular form spiral braid 12. Of course, the principle of operation of the finished spiral braid 12 is one of elongating the length of the spiral braid by applying tension between the ends thereof, so that the braid elongates, thereby lessening the diameter of the opening therein. When a compressive force is applied to the spiral braid, the braid diminishes in length but expands in diameter. Keeping this principle in mind, it can be seen from FIGS. 2 and 3, that the spiral braid 12 is under tension from the variable tension arrangement 20 at the second end of the housing 10. In operation, when the connector pin 36 is inserted through the openings in the pressure plate 24 and base plate 28 into the spiral braid 12, the spiral braid at the open end thereof will frictionally contact the inserted end of the pin 36, thereby causing the spiral braid to oppose the elongation tension causing the braid to compress. As the lenth of the braid diminishes, the opening diameter within the spiral increases allowing the pin to slip in. Thus, the compression of the braid 12 allows the pin 36 to be inserted. The pin's own insertion force friction within the spiral braid 12 causes the braid compression. This can best be seen in FIG. 4, where the braid is shown compressed by the force of the pin being inserted. It can be seen, that the angle at which the strands are woven with respect to the central axis of the tubular form spiral braid 12 effect the operation of the spiral braid. The preferred embodiment would be to weave the strands nearest the opening at the second end of the housing at the largest angle with respect to the central axis of the braid. Thus, the spiral braid at the open end thereof will be in a small diameter condition when under tension so that immediate frictional contact is made with the pin, thereby transferring the force applied to the pin to the spiral against the tension, so that the braid tends to start compressing in length opening the diameter so that the pin slides therein until it is fully inserted. The angle which the particular loop of the spiral makes with the central axis of the spiral braid is also important with respect to the gripping friction applied to the connector pin, when a removal force is applied thereto. It will be appreciated, that the removal force tends to increase the tension on the spiral braid 12, thereby causing the braid to elongate and reduce its diameter, thereby gripping the enclosed pin. Of course, if the bottom spiral or the spiral closest to the opening is wound or woven at a large angle with respect to the central axis, it tends to provide the gripping friction earlier than the other loops of the spiral by virtue of the fact that it is in a smaller diameter condition in the compressed state. The more removal force applied to the pin 36 the more the tension applied to the spiral braid increases, tending to tighten the loops of the spiral about the pin, thereby increasing frictional grip thereon preventing the removal.
If removal of the pin 36 is desired, the gripping force can be easily relieved, by manually moving the pressure plate 24 towards the base plate 28 against the spring tension, thereby relieving the tension on the spiral braid 12 allowing the pin to be removed.
It should be appreciated, that the pin 36, when in place within the spiral braid 12, has the loops of the braid in close contact about the entire surface of the pin when the braid is under tension, thereby making maximum use of the connecting surface so that a low resistance electrical path is provided. Accordingly, a very small voltage drop will be encountered in this connector, thereby making it useful for a low voltage, high current application.
While the invention has been particularly shown and described with reference to preferred embodiment thereof, it will be understood by those skilled in the art that the various changes in form and detail may be made therein without departing from the spirit and scope of the invention.