AU1786200A - Method and device for separating a connector from an electronic card - Google Patents

Description

A METHOD AND A DEVICE FOR SEPARATING A CONNECTOR FROM AN ELECTRONIC CIRCUIT BOARD The invention relates to a method of separating a connector from an electronic circuit board. It relates 5 more particularly to connectors which have terminals which are force-fitted into holes in electronic circuit boards. Electronic circuit boards generally perform a multiplicity of functions with the aid of a large number 10 of components. They are usually manufactured automatically. It is currently standard practice to employ connectors whose terminals are force-fitted into corresponding holes in the circuit boards. Compared to a soldered connection, this technique has the advantage of 15 faster fabrication. It is also less polluting than soldering. To make force-fitting possible, each terminal has a pointed end extended by a larger part which has an opening or a weakened area in its central portion so that 20 the width of the larger part can be reduced when the terminal is force-fitted into a hole in a circuit board. Before insertion, the larger part has a section slightly greater than the section of the hole. Accordingly, when the initially larger part is trapped in the hole, it 25 applies pressure against the edge of the hole. This pressure ensures contact with the conductive rims of the hole and also provides a gas seal between the two faces of the circuit board. The operation of force-fitting the connector 30 terminals is usually the last step in the fabrication of the circuit board. It must be possible to extract the connector without damaging the circuit board if it is defective or if its terminals are inserted incorrectly. After the components 35 have been inserted the circuit board has high value and it is therefore preferable not to discard it. Until now, cutters have been used to cut off the 2 inserted terminals in order to extract a defective connector or one whose terminals have been inserted incorrectly. That technique is time-consuming and difficult to put into practice. What is more, it is not 5 reliable and entails the risk of injury to the operator. The invention removes these drawbacks. The method according to the invention consists in exerting an extraction force simultaneously on all the terminals of the connector. To this end, either pressure 10 is applied to the ends of all the terminals which project from one face of the circuit board or traction is applied to the body of the connector. The risk of damaging the circuit board is minimized because the forces are distributed between the terminals 15 and are applied to the terminals at the same time. What is more, since the forces can be exerted perpendicularly to the plane of the circuit board, tools can be used whose footprint in the plane of the circuit board is practically limited to that of the connector and 20 therefore entails no risk of damaging tracks or components in the vicinity of the connector to be extracted. In a first embodiment of an extractor device using the above method, a first part of the device has a 25 surface adapted to be pressed against the ends of the terminals and means for holding the circuit board while pressure is applied to the ends of the terminals. The holding means preferably comprise an end surface of a second part which is on the opposite side of the circuit 30 board to the first part and includes a housing to receive the connector to be extracted. The housing can instead be formed in a part independent of the holding means. When the connector has a pin extending each terminal, it is advantageous to provide guide means for 35 guiding the pins on the opposite side of the circuit board to the first part. The guide means make the forces applied to the connector more homogeneous and limit the 3 risk of deformation of the terminals and the pins, which could impede extraction. The guide means preferably have a lower surface which constitutes the means for holding the circuit board. 5 The above extractor device can be used in a conventional press including an anvil in the lower part (or in the upper part) and a pressing device in the upper part (or in the lower part). In this case, the first part, which includes the surface which is pressed against 10 the ends of the terminals, is fastened to the anvil and the second part is (or the guide means are) fastened to the pressing tool. The circuit board can be fixed to a mobile table. The anvil and the pressing device are moved 15 simultaneously so that the pressing surface comes into contact with the ends of the terminals when the pressing device is holding the circuit board. In another embodiment of the extractor device according to the invention, which is a preferred 20 embodiment, when there are no pins to provide guidance on the side of the circuit board opposite the terminals, the device includes means for holding the connector body by gripping it and means for applying traction to the connector body in the extraction direction. The means 25 for applying the traction preferably include screw means converting the rotation torque of a screw into a translation force. The connector body holding means comprise hook means complementary to cells or recesses in the body, for 30 example. The invention provides a method of separating a connector from an electronic circuit board when terminals of the connector have been force-fitted into corresponding holes in the circuit board. The method is 35 characterized in that an extraction force is applied which is divided between all the force-fitted terminals. In a first embodiment, pressure is applied to the 4 ends of the terminals. In a second embodiment, traction is applied to the connector body on the side of the circuit board opposite the terminals. 5 The present invention further provides a device for implementing the first embodiment of the method and which includes a first part with a surface adapted to be pressed against the ends of the terminals of the connector to be extracted and means for holding the 10 circuit board. In one embodiment of the invention the device includes a housing or recess to receive the connector to be extracted on the side of the circuit board opposite the first part. 15 In one embodiment of the invention the housing constitutes a recess in a member whose end surface, into which the recess opens, constitutes a surface bearing against the circuit board to hold it. In one embodiment of the invention when the 20 connector to be extracted has pins extending the terminals, the housing is separated into compartments for guiding each of the pins. In one embodiment of the invention the terminals are aligned in one or more planes and the pressing surface 25 has one or more grooves for positioning the ends of the terminals. In one embodiment of the invention when each terminal of the connector is extended by a pin, the device comprises means for guiding the pins during 30 extraction on the side of the circuit board opposite the first part. In one embodiment of the invention the parts of the device on respective opposite sides of the circuit board have a footprint in the plane of the circuit board which 35 is not very different from the footprint of the connector. In one embodiment of the invention the guide means 5 include a comb whose teeth are inserted between the pins or rows of pins. In one embodiment of the invention the teeth of the comb have an outside edge inclined so that the teeth do 5 not impede access to the surface of the circuit board in the vicinity of the connector to be extracted. A device for implementing the second embodiment of the method includes means for holding the body of the connector on the side opposite the terminals to be 10 extracted from the holes in the circuit board and means for applying traction to the holding means. In one embodiment of the invention the traction means are of the screw type. In one embodiment of the invention the holding means 15 comprise projections or teeth inserted into recesses or cells in the body of the connector. Other features and advantages of the invention become apparent in the light of the following description of a few embodiments of the invention, which description 20 is given with reference to the accompanying drawings, in which: Figure 1 is a diagram showing a first embodiment of a connector extractor device according to the invention, Figures la and lb are diagrams showing connector 25 terminals, Figure 2 is a diagram analogous to that of Figure 1 and relates to another step in the operation of the device, Figure 3 is a diagram showing the whole of the 30 device from Figure 1, Figure 4 shows a circuit board support for the device shown in Figure 3, Figure 5 is a diagram showing a coaxial connector, Figure 6 is a diagram showing tools adapted to be 35 mounted on the device shown in Figure 3 for extracting coaxial connectors, Figure 7 is a diagram showing another type of 6 connector, Figure 8 is a diagram showing tools that can be used in the device shown in Figure 3 to extract the connector shown in Figure 7, 5 Figure 9 shows a further type of connector, Figure 10 shows tools adapted to be mounted on the device shown in Figure 3 for extracting the connector shown in Figure 9, Figure 11 is a diagram showing an angled connector, 10 Figure 12 shows tools adapted to be mounted on the device shown in Figure 3 for extracting connectors of the type shown in Figure 11, Figure 13 is a diagram showing a connector with no exposed pins at the top, 15 Figure 14 is a diagram showing a device for extracting a connector of the type shown in Figure 13, Figure 15 is a diagram showing a push-on tongue type connector, and Figure 16 is a diagram showing a device for 20 extracting a push-on tongue type connector. The principle of force-fitting connector terminals is first described in outline. A connector designed to be assembled to a circuit board 20 (Figure 1) without soldering has a plurality of 25 terminals which are the shape shown in Figure la or Figure lb before they are inserted into corresponding holes in the circuit board. In Figure la, the terminals 22 have a larger portion 24 whose largest dimension is slightly greater than the 30 diameter of the hole (not shown) into which it must be inserted. To enable force-fitting, an opening 26 is provided at the center of the larger portion 24. Accordingly, when the terminal is force-fitted, the walls of the larger portion apply pressure to the rims of the 35 hole. The example shown in Figure lb is analogous to that shown in Figure la, from which it differs in that the 7 larger portion 24' does not have any opening in it, but instead a solid part 28 or web which can deform on force fitting and by virtue of which the walls of the larger portion 24' apply pressure to the rims of the hole. 5 A connector 30 has a body 32 (Figure 1) from which the terminals 221, 222, etc. project. After insertion, the body 32 is on one side of the circuit board 20 and the ends of the terminals 22i are on the other side of the same circuit board. 10 It may be necessary to detach the connector 30 from the circuit board 20 for various reasons: to modify the board, to repair or change components near the connector, because of one or more blocked holes or a connector positioning error, to replace a connector because of a 15 fault, etc. The invention enables fast extraction of the terminals with minimum risk to the integrity of the circuit board 20 and its components. It consists of holding the circuit board 20 and 20 simultaneously applying to all the terminals 22i an extraction force in the direction that moves the body 32 away from the circuit board 20. In the embodiments shown in Figures 1, 2, 3, 4, 6, 8, 10 and 12 pressure is applied to the free end of the terminals 22i and in the 25 embodiments shown in Figures 14 and 16 traction is applied to the connector on the side of the circuit board opposite the terminals. In the first embodiment of the invention, support means are provided for the circuit board 20, a bottom 30 tool 34 has a top surface 36 adapted to come into contact with the ends of the terminals 22,, 222, etc. and a top tool 38 has a bottom surface 40 adapted to bear on the top face 20, of the circuit board 20 to hold it onto its support. The tool 38 also includes a housing 42 for the 35 body 32 of the connector 30 or its upper parts. The opening of the housing 42 faces downwards to receive the body 32.

8 The qualifiers "bottom" and "top" used here are intended to facilitate the description of the device according to the invention, but it goes without saying that the parts and tools 34 and 38 can be disposed with 5 any orientation. All that is required is for the tools to be disposed on respective opposite sides of the circuit board 20. Figure 1 shows a circuit board 20 and the tools 34 and 38 before the tools perform their function and Figure 10 2 shows the circuit board 20 and the tools 34 and 38 after they have performed their function, that is to say after the terminals 22k, 222, etc. have been pushed up. Depending on the type of connector, the connector body 32 is either pushed up inside the housing 42 or remains in 15 position. The tools 34 and 38 move between the positions shown in Figures 1 and 2 at the same time. The surface 40 comes into contact with the surface 20, of the circuit board 20 after the surface 36 comes into contact with the 20 ends of the terminals 22. In the embodiment of the invention shown in Figure 3, the tools 34 and 38 are fixed to a conventional press 46, for example a SCHMIDT manual lever press with a swan neck support 48. As shown in Figure 3, the press is 25 operated by a lever 50. The circuit board 20 is installed on a mobile table 52 (Figure 4) and controls (not shown) are used to move the table along two perpendicular axes in a plane. The table 52 has two parallel supports 54 and 56 for 30 an imprint 58 adapted to receive the circuit board 20 (not shown in Figure 4). In this example, the support 56 includes a groove 60 for receiving a rim of the imprint 58, the parallel rim resting on the support 54. The number of imprints provided corresponds to the number of 35 types of circuit board manufactured and likely to need to be repaired. Note that when the extractor device has performed 9 its function, the ends of the terminals remain inside the holes in the circuit board 20. However, the part of each terminal remaining in one of the holes in the circuit board 20 has a section smaller than that of the hole, 5 enabling them to be extracted easily, for example by hand. The tools 34 and 38 naturally have shapes and sizes suited to the connector to be repaired. Figures 5 and 6 show a first example of the tools. 10 Figure 5 shows a coaxial connector 59 whose body 60 is generally parallelepiped-shaped on a square base and which has five terminals 22, to 22, at the bottom, with four of the terminals near the corners of the square base and one terminal 25, at the center. The upper part of the 15 parallelepiped-shaped body 60 is extended by a coaxial cylindrical part 62. The bottom tool 34 has a plane bearing surface 36 adapted to press upwards on the ends of the terminals 22i and the tool 38 includes a housing 42 which has a 20 parallelepiped-shaped section and is adapted to receive the body 60, 62 of the connector 59. The tools 34 and 38 can be removed from the press 46. The tool 38 therefore incorporates a hole 64 for a retaining pin. 25 In this example, the body 60, 62 moves into the housing 42 during extraction. The embodiment of the invention shown in Figure 8 is intended for extracting "Mate-N-Lock" connectors, one of which is shown in Figure 7. A "Mate-N-Lock" connector 66 30 has a plurality of contact members 67, for example three such members, each of which has four terminals 22, to 224 at the bottom (although they are shown at the top in Figure 7), all of which are attached to the same metal ring 68. The upper part of the member 67 includes a pin 35 70 (shown at the bottom in Figure 7). The terminals 22, to 224 are force-fitted into corresponding holes in the circuit board 20. The pin 70 makes electrical contact 10 with a complementary female connector. In this example, the circuit board 20 is shown the other way up compared to the embodiment previously described, that is to say with the terminals 22ii at the 5 top and the remainder of the connector at the bottom. This being the case, the tool 34 with its pressing surface 36 is at the top and the tool 38 is at the bottom. The housing 42 naturally has a shape and a section adapted to receive and guide the body of the 10 connector 66. The tools shown in Figure 10 are for extracting connectors of the type shown in Figure 9, that is to say with an elongate U-shaped insulative body 72 whose base 74 forms a strip from the bottom of which the terminals 15 221, 222, etc. project and on top of which are contact pins 761, 762, etc. extending the respective terminals 221, 222, etc. The pins 761, 762, etc. are therefore disposed in the space formed between the two larger lateral walls 78 20 and 80. On the side opposite the base 74, the body of the connector has an opening to provide access to a complementary female connector (not shown). The part 34 is at the bottom, as in the embodiment shown in Figure 6, and the tool 38 is at the top. 25 The top surface 36, of the tool 34 has a shallow rectilinear groove 82 in its central part. The groove is adapted to receive and position the ends of the terminals 22k, 222, etc. Its depth is less than the length of the terminals projecting from the bottom of the circuit board 30 20. The housing 42 in the part 38 is higher than the walls 78 and 80 and is divided into compartments (not shown in detail) each of which receives one of the pins 761, 762, etc. 35 The function of the compartments 42 is to guide each pin 761, 762, etc. individually so that the combination of the pin and the terminal that it extends cannot become 11 twisted. If it were to become twisted, extracting it would be more difficult. In all the embodiments described until now, the footprint of the tools in the plane of the circuit board 5 20 hardly extends beyond the footprint of the connector to be extracted. This being so, the operation to separate the connector does not entail any risk of damaging components or tracks in the vicinity of the connectors. 10 The tools shown in Figure 12 are intended to be used to extract angled connectors of the kind shown diagrammatically in Figure 11. An angled connector 90 includes a plurality of terminals disposed in parallel planes. Figure 11 shows 15 four terminals 26, to 264 in the same plane 92. For simplicity, only the locations of the parallel planes 94, 96, etc. in each of which a set of terminals is installed is shown. The terminals project from a base 98 of the body of the connector. Each is extended by a pin 1001, 20 1002, etc. between the base 98 and a ceiling 102. The pins are different lengths and each pin is extended at one end by a horizontal pin 104,, etc. that terminates in a female connection (not shown). The junctions between the vertical pins 1001, 1002 and the horizontal pins 1041, 25 1042 lie in an inclined plane. The space between the planes 92 and 94, 94 and 96, etc. is free and accessible from the same side as the external pins 1004. These spaces provide guidance during extraction. 30 Accordingly, to guide the combinations of the pins and the terminals so that they do not become twisted during extraction, a top tool 382 has a set of blades 110, 112, etc. at the bottom forming a comb whose teeth are inserted into the spaces between the planes 92 and 94, 94 35 and 96, etc. The blades or teeth are inclined to the vertical because of the shape of the spaces.

12 The inclination of the teeth of the comb means that the tool 382 must extend beyond the connector on the same side as the pins 1004. However, the outer edge 116 of each tooth is inclined so as not to impede access to 5 components or tracks in the vicinity of the connector. The embodiment of the invention described with reference to Figures 13 and 14 differs from those described above in that traction is applied to the body of the connector instead of applying pressure to the ends 10 of the terminals of the connector. The device shown in Figure 14 is more particularly suited to a connector 120 in which each terminal 26j is extended inside its body 122 by a pin which cannot be seen in the drawing and which is not accessible from the 15 outside. If pressure were applied to the ends of the terminals of a connector of this kind, it might twist the terminals or the pins extending them, as there is no facility for guiding the pins, which are embedded in the housing 122 of the connector. 20 In the example shown in Figure 14, there are recesses 124, 126, etc. on the longer sides of the body 122 of the connector. The device 130 shown in Figure 14 comprises two flanges, of which only the front flange 132 can be seen 25 in the figure. Each of the flanges 132 terminates in lugs 134, 136, 138 whose free ends have teeth 140 adapted to penetrate into the compartments or recesses 124, 126. The two flanges 132 co-operate with a threaded rod 142 and a wing-nut 144 to clamp the connector between the 30 lugs 134, 136, 138 of the two flanges 132. The upper part of each flange 132 is fixed to one face of a spacer 146 which receives a threaded rod 148 extended by a shaft 150 through which a Tommy bar 152 passes. The assembly comprising the spacer 146 and the flanges 132 is disposed 35 in a body 154 in the form of a clamp. The rod 148 passes through the upper part of the body 154 and the Tommy bar 152 is at the end opposite the lugs 134, 136 and 138.

13 To extract the terminals of the connector from the holes in the printed circuit board 20, it is necessary to hold the board 20 and to turn the Tommy bar 152 in the direction that raises the lugs 134, 136 and 138 and 5 therefore raises the body of the connector. The device shown in Figure 16 is for extracting a push-on tongue type connector (Figure 15) by applying traction. A push-on tongue type connector has an inverted T-shape 160 with a hole 162 at the top and 10 terminals 261, 262, 263 at the bottom. The device 164 shown in Figure 16 includes a body 166 whose lower part 168 includes a housing 170 adapted to receive the tongue 160. The tongue is fixed to the housing 170 by means of a pin passing through the hole 15 162 and a corresponding hole 174 in the device 164. In this example, extraction is effected by co-operation of a threaded rod 176 and a knurled nut 178.

Claims (15)

1. A method of separating a connector (30) from an electronic circuit board (20) when terminals (221, 222) of the connector are force-fitted into corresponding holes 5 in the circuit board, characterized in that an extraction force is applied which is divided between all of the force-fitted terminals.

2. A method according to claim 1, characterized in that pressure is applied to the ends of the terminals. 10

3. A method according to claim 1, characterized in that traction is applied to the body of the connector on the side of the circuit board opposite the terminals.

4. A device for implementing a method according to claim 2, characterized in that it has a first part (34) 15 with a surface (36) adapted to be pressed against the ends of the terminals of the connector to be extracted and means for holding the circuit board.

5. A device according to claim 4, characterized in that it includes a housing (42) or recess adapted to receive 20 the connector to be extracted on the side of the circuit board opposite the first part.

6. A device according to claim 5, characterized in that the housing constitutes a recess in a part (38) which has an end surface (40) onto which the recess opens and which 25 constitutes a surface bearing against the circuit board to hold it.

7. A device according to any one of claims 4 to 6, characterized in that the connector to be extracted has pins extending the terminals and the housing is separated 30 into compartments for guiding each of the pins. 15

8. A device according to any one of claims 4 to 7, characterized in that the terminals are aligned in one or more planes and the pressing surface has one or more grooves (82) for locating the ends of the terminals. 5

9. A device according to claim 4, characterized in that each terminal of the connector is extended by a pin and the device comprises means for guiding the pins during extraction on the side of the circuit board (20) opposite the first part.

10 10. A device according to any one of claims 4 to 9, characterized in that the parts of the device on respective opposite sides of the circuit board have a footprint in the plane of the circuit board that is not very different from the footprint of the connector. 15

11. A device according to claim 9, characterized in that the guide means include a comb whose teeth (110, 112) are inserted between the pins or rows (92, 94, 96) of pins.

12. A device according to claim 11, characterized in that the teeth of the comb have an outside edge (116) 20 which is inclined so that the teeth of the comb do not impede access to the surface of the circuit board in the vicinity of the connector to be extracted.

13. A device for implementing a method according to claim 3, characterized in that it includes holding means 25 for holding the body of the connector on the side of the circuit board opposite the terminals to be extracted from the holes in the circuit board and means for applying traction to the holding means.

14. A device according to claim 13, characterized in 30 that the means for applying traction are of the screw type. 16

15. A device according to claim 13 or claim 14, characterized in that the holding means comprise projections or teeth (140) which are inserted into recesses (124, 126) or cells in the body of the 5 connector.