Patent Grant
7484989
Reference is made to U.S. Patent Application Pub. No. 2005/0112920 A1, published May 26, 2005, which is incorporated herein by reference in its entirety.
The invention is in the general field of electrical connectors.
Latches for retaining cable assemblies to their mating connectors have many designs. Of these designs, many use the same motion for unlatching as for extraction. That is, to remove an assembly from its mating connector, one would most naturally pull on the plug end. It is most desirable that this same pulling action effects the unlatching. Conversely, when mating the plug with its connector, the most common designs automatically latch using a combination of a spring and a ramp.
Regardless of feature shape or specific design, one principle applies to all: when pulling to disengage the connector, ramp-spring friction will resist movement of the latch. The friction that exists between the latch and its mate is a function of the pulling force on the connector, which causes a normal force between the latch and its mating part, and the coefficient of friction between the latch and the mating part. The pulling force on the latch to effect the unlatching is the sum of the force required to compress the spring that biases the position of the latch, and any other force imposed; for example, the weight of a hanging cable. The net mechanical advantage of the latch actuating mechanism must overcome this friction or the latch will not function.
From the foregoing it will be appreciated that there is the possibility of improvements for such latches.
According to an aspect of the invention, an a electrical connector latch has a low coefficient of friction surface, such as coating or an overmolded plastic, on its metal end. The metal end may be a hooked metal end that provides strength.
According to another aspect of the invention, an electrical connector includes: a connector body; a pair of latches having latch ends that pivot relative to the connector body about pivots of the latches; a pair of springs that bias the latch ends toward an engaged position, for engaging mating slots or protrusions of a mating connector; and a pair of ramps that cooperate with the springs to pivot the latch ends from the engaged position to a disengaged position, for disengaging from the mating slots or protrusions. The latch ends have low coefficient of friction mating surfaces for engaging the mating slots when the latch ends are in the engaged position.
According to yet another aspect of the invention, a pair of mated electrical parts include a cable assembly and a mating connector. The cable assembly includes a connector body that encloses electrical contacts; and a pair of latches having latch ends that pivot relative to the connector body about pivots of the latches. The mating connector, which is mechanically and electrically coupled with the electrical connector, includes matting connector electrical contacts that mate with the electrical contacts of the cable assembly; and engagement structures on opposite sides of the matting connector electrical contacts. The engagement structures each have one or more prongs that engage corresponding receptacles in the connector body of the cable assembly.
To the accomplishment of the foregoing and related ends, the invention comprises the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings.
In the annexed drawings, which are not necessarily to scale:
A latch end for an electrical connector latch has a low coefficient of friction latch mating surface that engages with a mating slot in a mating electrical connector. The latch pivots around a central pivot point to move the latch end inward toward the center of the connector to engage the mating slot, or outward away from the center of the connector to disengage from the slot. The low friction mating surface may be a plastic overmold or a low friction coating on a metal hook of the latch end. The metal hook provides strength to the latch end. The low friction mating surface provides for a lower coefficient of friction and perhaps a larger contact area between the mating surface and the mating slot or protrusion. This reduces the friction forces that oppose disengagement of the latch by pulling on the body of the electrical connector. The latch may be biased into engagement with the mating slot by a ramp-and-spring mechanism of the electrical connector. The mechanism has a spring that pushes out against the latch on one side of the central pivot, causing the latch end on the other side of the pivot to be pushed inward. A ramp on the connector body may push inward against the latch, counteracting the spring force, when the electrical connector is pulled to disengage it from its mating connector. The inward push by the ramp causes the latch end to move outward, a move that is opposed by friction between the latch end and the mating slot. By reducing friction between the latch end and the mating slot, easier disengagement between the electrical connector and the mating connector is facilitated.
Referring now in addition to
As the grip portion 140 is pulled back, in the direction of the cable 12, a ramp or sloped surface 160 of the grip portion 140 presses against the cam surfaces 154, deflecting the second end 152 of the latch 136 inward, against the force of a biasing spring 170. A similar ramp or sloped surface on a top half of the grip portion 140 presses against the top cam surface 154. As the second end 152 of the latch 136 is pressed inward, the latch 136 rotates about its axis 150, moving the first end 144 of the latch 136 outward. This moves the latch end 138 outward as well, releasing the latch end 138, and allowing the cable assembly 128 to be disengaged from a mating female connector.
The biasing spring 170 is between the back shell 130 and an inner surface 172 of the second end 152 of the latch 136. The biasing spring 170 fits into a recess in the inner surface of the second end 152, and serves to always press the second end 152 of the rocker 148 outward. When the grip portion 140 is released, the grip portion 140 translates back along the back shell 130, allowing the latch end 138 to engage, driven by the biasing spring 170.
The latch end 138 includes a hook made of a suitable metal, such as steel. The metal hook of the latch end 138 provides strength to the latch end 138. The latch end 138 also has low coefficient of friction mating surface 173 that engages a slot or protrusion of a mating electrical connector. The first end 144 of the latch 136 may have a plastic overmold 174 that includes the low coefficient of friction mating surface 173. The mating surface 173 may be at a substantially a right angle to a length of the latch 136 extending from the pivot 150 to the latch end 138.
The low coefficient of friction mating surface 173 provides reduced friction between the latch end 138 and the mating slot or protrusion on a female connector. In comparison with latches that involve metal latch ends, such as bare metal hooks, as a mating surface, the low friction mating surface provides for a lower coefficient of friction. In addition, the low friction mating surface may provide a larger contact area that a bare metal end between the mating surface and the mating slot. This reduces the friction forces that oppose disengagement of the latch by pulling on the body of the electrical connector. It will be appreciated that the pull on the connector 130 by the cable 141 may also cause normal forces on the mating surface 173, which produce frictional forces. By reducing friction between the latch end and the mating slot, easier disengagement between the electrical connector and the mating connector is facilitated.
As an alternative to the plastic overmold 174, the low coefficient of friction mating surface 173 may be a suitable low friction coating on metal parts of the latch end 138.
The latch release mechanism 134 provides an intuitive mechanism for disengaging the cable assembly from a female connector. The same pulling action that disengages the latch ends 138 is also used for pulling the cable assembly 128 away from the female connector. A pull loop 142 may be provided as an alternate mechanism for disengaging the latch ends 132.
As an alternate way of releasing the latch 136, an outer protrusion 175 of the latch second end 152 may protrude outside of the grip portion 140. Depressing the protrusion 175 causes the latch 136 to pivot, and the latch end 138 to thereby disengage. It will be appreciated that the latch release mechanism 134 provides a large mechanical advantage, which allows release of the latch ends 138 with a small force. The amount of mechanical advantage may be varied by varying suitable dimensions of the latch release mechanism 134, for example by varying the slope of the sloped surfaces of the back shell portions.
The back shell 130 may be made of a suitable metal, such as aluminum or steel. The grip portion 140 may be made of a suitable plastic material. The grip portion 140 may have a ridged gripping surface 176, to aid in gripping and pulling on the grip portion 140.
The prongs 242-245 may engage open slots 246 in the back shell 130. Alternatively the prongs 242-245 may engage recesses 248 in the back shell 130 that are partially closed, open only where the slots receive the prongs 242-245 and other parts of the engagement structures 222 and 224. The slots 246 and recesses 248 are collectively referred to herein as “receptacles.”
The engagement structures 222 and 224 also have respective slots 252 and 254 for receiving and engaging the latch ends 138 of the cable assembly 128. The slots 252 and 254 have a rectangular shape. Ramps 256 and 258 on the structures 222 and 224 may be used to urge the latch ends 138 outward as the back shell 130 is engaged with the electrical connector 220. As the back shell 130 is inserted further the latch ends 138 reach the slots 252 and 254. There the latch ends 138 snap inwards, engaging the slots 252 and 254 and latching the parts together.
The engagement structures 222 and 224 may each be a single piece of material. The material may be any suitable material, such as a suitable metal or plastic.
Although the invention has been shown and described with respect to a certain preferred embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described elements (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.
Priority is claimed under 35 USC 119 to U.S. Provisional Application No. 60/861,631, filed Nov. 29, 2006, which is incorporated herein by reference in its entirety.
| Number | Name | Date | Kind |
|---|---|---|---|
| 4655518 | Johnson et al. | Apr 1987 | A |
| 4655578 | Kurtz et al. | Apr 1987 | A |
| 4659155 | Walkup et al. | Apr 1987 | A |
| 4755145 | Johnson et al. | Jul 1988 | A |
| 4846727 | Glover et al. | Jul 1989 | A |
| 4869677 | Johnson et al. | Sep 1989 | A |
| 4961711 | Fujiura et al. | Oct 1990 | A |
| 4976628 | Fedder | Dec 1990 | A |
| 4984992 | Beamenderfer et al. | Jan 1991 | A |
| 5046960 | Fedder | Sep 1991 | A |
| 5055069 | Townsend et al. | Oct 1991 | A |
| 5066236 | Broeksteeg | Nov 1991 | A |
| 5104329 | Brown et al. | Apr 1992 | A |
| 5104341 | Gilissen et al. | Apr 1992 | A |
| 5151036 | Fusselman et al. | Sep 1992 | A |
| 5154629 | Carver et al. | Oct 1992 | A |
| 5174770 | Sasaki et al. | Dec 1992 | A |
| 5238414 | Yaegashi et al. | Aug 1993 | A |
| 5286212 | Broeksteeg | Feb 1994 | A |
| 5342211 | Broeksteeg | Aug 1994 | A |
| 5403206 | McNamara et al. | Apr 1995 | A |
| 5435757 | Fedder et al. | Jul 1995 | A |
| 5443403 | Weidler et al. | Aug 1995 | A |
| 5460533 | Broeksteeg et al. | Oct 1995 | A |
| 5484310 | McNamara et al. | Jan 1996 | A |
| 5496183 | Soes et al. | Mar 1996 | A |
| 5525066 | Morlion et al. | Jun 1996 | A |
| 5620340 | Andrews | Apr 1997 | A |
| 5632634 | Soes | May 1997 | A |
| 5632635 | Vanbesien et al. | May 1997 | A |
| 5660551 | Sakurai | Aug 1997 | A |
| 5664968 | Mickievicz | Sep 1997 | A |
| 5702258 | Provencher et al. | Dec 1997 | A |
| 5775947 | Suzuki et al. | Jul 1998 | A |
| 5795191 | Preputnick et al. | Aug 1998 | A |
| 5860816 | Provencher et al. | Jan 1999 | A |
| 5882214 | Hillbish et al. | Mar 1999 | A |
| 6102747 | Paagman | Aug 2000 | A |
| 6146202 | Ramey et al. | Nov 2000 | A |
| 6270382 | Droesbeke et al. | Aug 2001 | B1 |
| 6371773 | Crofoot et al. | Apr 2002 | B1 |
| 6471547 | Venaleck et al. | Oct 2002 | B1 |
| 6524135 | Feldman et al. | Feb 2003 | B1 |
| 6780069 | Scherer et al. | Aug 2004 | B2 |
| 6857899 | Reed et al. | Feb 2005 | B2 |
| 6866542 | Murayama | Mar 2005 | B2 |
| 6910911 | Mellott et al. | Jun 2005 | B2 |
| 6953356 | Hisamatsu et al. | Oct 2005 | B2 |
| 6953361 | Li et al. | Oct 2005 | B2 |
| 7001200 | Yoshie | Feb 2006 | B2 |
| 20030124881 | Avery et al. | Jul 2003 | A1 |
| 20030186594 | Feldman et al. | Oct 2003 | A1 |
| 20050112920 | Venaleck et al. | May 2005 | A1 |
| Number | Date | Country |
|---|---|---|
| 03084003 | Oct 2003 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20080124973 A1 | May 2008 | US |
| Number | Date | Country | |
|---|---|---|---|
| 60861631 | Nov 2006 | US |
