1. Field of the Invention
The invention relates to a heat shrinkable tube mount method and a heat shrinkable tube mounting jig for mounting a heat shrinkable tube to a terminal-equipped electric wire whose core wire is crimped to a core wire crimp section of a terminal.
2. Description of the Related Art
When; for instance, an earth terminal crimped to an electric wire, is connected to an auto body that is an area to be exposed to water, water sometimes penetrates into the electric wire from a bare portion of the core wire crimped to the earth terminal, thereby entering a device or equipment connected to the other end of the electric wire. In order to prevent occurrence of water ingress via such a route, a swaged portion of the terminal is often subjected to waterproof treatment (see; for instance, PTL 1).
Incidentally, for instance, a jig 503 attached to a jig grip 501 shown in
In the jig 503, an end of the heat shrinkable tube 521 that covers the extremities of the core wires 515 is pressed by the tube press 509, thereby preventing occurrence of milk-off (a phenomenon in which a molten adhesive works as a lubricant, to thus move the heat shrinkable tube 521) or shrink-back (a phenomenon in which a length of the heat shrinkable tube 521 contracts). As a result, the molten adhesive reaches the adhesive flow stopper 511 without fail.
[PTL 1] Japanese Patent Publication No. JP-A-2005-135858
However, in the existing jig 503, a periphery of the cylindrical heat shrinkable tube 521 is pressed by the small-plate-like tube press 509 having an L-shaped bend. Therefore, anchorage strength of the heat shrinkable tube 521 cannot be increased, and the heat shrinkable tube 521 might be thrust back by the adhesive that has been extruded during shrinkage and collided against the adhesive flow stopper 511 to thereby come off the tube press 509. If the heat shrinkable tube 521 comes off the press, the adhesive might effuse to an unwanted area to thereby deteriorate reliability of a water stop structure. Since clearance 525 is formed between the heat shrinkable tube 521 and the adhesive flow stopper 511, a problem of an increase in amount of adhesive outflow arises.
The invention has been conceived in light of the circumstance and aims at providing a heat shrinkable tube mount method, a heat shrinkable tube mounting jig, and a terminal-equipped electric wire that make it possible to reliably fix a heat shrinkable tube without involvement of an adhesive leakage and fill the heat shrinkable tube, which is located in close proximity to an electrical contact, up to its open end with an adhesive.
In order to achieve the object described above, a heat shrinkable tube mount method and a heat shrinkable tube mounting jig according to the invention is characterized by the following (1) to (7).
(1) A heat shrinkable tube mount method comprising:
a step of fitting a terminal of a terminal-equipped electric wire to a terminal fit recess of a lower frame provided on a base;
a step of sheathing a core wire crimp section of the terminal led out of the lower frame with a heat shrinkable tube containing therein an adhesive and bringing a one tube end into contact with a dam wall of the lower frame;
a step of restricting movement of the terminal in a direction orthogonal to one plane of the terminal, by covering the terminal fit recess with an upper frame that is joined to the lower frame in a turnable manner;
a step of pinching a portion of a peripheral wall of the heat shrinkable tube between a tube fixing claw projectingly provided on the upper frame and the terminal at an instant when the upper frame covers the terminal fit recess; and
a step of turning a clamp lever, which is provided on the base in a turnable manner, to a pinching position, where the clamp lever pinches the lower frame and the upper frame.
According to the heat shrinkable tube mount method having the configuration described in connection with (1), the heat shrinkable tube into which the core wire crimp section of the terminal fitted to the terminal fit recess of the lower frame is brought into contact with the one tube end of the dam wall of the lower frame. A space that is to be filled with an adhesive and that is closed by the dam wall is formed at an opening of the one tube end. The upper frame is turned in this state, whereupon the terminal is fixedly pinched between the lower frame and the upper frame. The tube fixing claw provided on the upper frame is pressed against the portion of the peripheral wall of the one tube end at an instant when the terminal is fixed. Thus, the portion of the peripheral wall is pinched between the terminal and the tube fixing claw. The one tube end is fixed in close proximity to the dam wall without clearance from which an adhesive might run out.
(2) A heat shrinkable tube mounting jig comprising:
a lower frame that is provided on a base and that has a terminal fit recess for restricting in-plane movement of a terminal of a terminal-equipped electric wire;
a dam wall that is formed on the lower frame and with which a one tube end of a heat shrinkable tube, in which a core wire crimp section of the terminal is sheathed, is brought into contact;
an upper frame that is joined to the lower frame in a turnable manner and covers the terminal fit recess, to thus restrict movement of the terminal in a direction perpendicular to the one plane of the terminal;
a tube fixing claw that is provided projectingly on the upper frame and that pinches a portion of a peripheral wall of the heat shrinkable tube along with the terminal; and
a clamp lever that is provided on the base in a turnable manner and that is turned to a pinching position, to thus pinch the lower frame and the upper frame.
In the heat shrinkable tube mounting jig having the configuration described in connection with (2), the terminal is positioned in the terminal fit recess of the lower frame. When the core wire crimp section of the terminal positioned in the terminal fit recess is sheathed in the heat shrinkable tube, the one tube end of the heat shrinkable tube is brought into contact with the dam wall. At an instant when the upper frame is turned and when the terminal is fixedly pinched between the lower frame and the upper frame, the tube fixing claw provided projectingly on the upper frame is pressed against the portion of the peripheral wall of the one tube end. The tube fixing claw pinches the portion of the peripheral wall of the one tube end between the lower frame and the upper frame. Accordingly, the one tube end can be pinched without fail. Further, the opening of the one tube end is closed by the dam wall, and a portion of the peripheral wall is fixed to the base by means of the terminal and the tube fixing claw. This eliminates clearance between the dam wall and the one tube end from which an adhesive might run out. Thus, the one tube end can be positioned in close proximity to the electrical contact of the terminal.
(3) The heat shrinkable tube mounting jig according to the above (2), wherein the tube fixing claw as a plurality of parallel press teeth that extend in a direction orthogonal to an axial direction of the heat shrinkable tube.
In the heat shrinkable tube mounting jig having the configuration described in connection with (3), the tube fixing claw that presses the one portion of the peripheral wall of the heat shrinkable tube assumes a shape of pressing teeth. Hence, the tube fixing claw can pinch the portion of the peripheral wall by dint of contact pressure that is greater than that generated by a planar fixing claw. Hence, disengagement of the heat shrinkable tube becomes more difficult.
(4) The heat shrinkable tube mounting jig according to the above (2) or (3), wherein the base has a temporary retention claw that is engaged with an edge of the terminal positioned in the terminal fit recess, thereby restricting uplift of the terminal from the terminal fitting recess.
In the heat shrinkable tube mounting jig having the configuration described in connection with (4), the terminal can be temporarily retained in the terminal fit recess before the turned upper frame covers the terminal fit recess. Work for sheathing a core crimp section that must be performed before turning of the upper frame is facilitated.
(5) The heat shrinkable tube mounting jig according to any one of above (2) to (4), wherein the base is provided with a plate for ensuring clearance to be filled that is inserted between a plurality of electric wires connected to the terminal.
In the heat shrinkable tube mounting jig having the configuration described in connection with (5), when the electric wire connected to the terminal is plural, the plate for ensuring clearance to be filled is inserted between the electric wires, thereby preventing twisting of the plurality of electric wires, and the plurality of electric wires can be laid in parallel. Thereby, clearance between the electric wires can be t filled with an adhesive, thereby preventing occurrence of a space not to be filled with an adhesive between the electric wires.
(6) The heat shrinkable tube mounting jig according to any one of the above (2) to (5), wherein the terminal fitting recess fits to the terminal in a direction in which the core wire crimp section faces down, and the tube fixing claw pinches the portion of the peripheral wall along with a terminal back face, which is an opposite side, of the core wire crimp section.
In the heat shrinkable tube mounting jig having the configuration described in connection with (6), the terminal back face of the terminal fitted to the terminal fit recess faces up, and the core wire crimp section faces down. In the heat shrinkable tube into which the core wire crimp section is sheathed, the portion of an upper peripheral wall is pinched between the terminal back face and the tube fixing claw, and the other portion of the peripheral wall except the one of the peripheral wall surrounds the core wire crimp section located at a lower position, to thus form a sagging. The adhesive converges at the core wire crimp section located at the lower position, whereby the core crimp section in the heat shrinkable tube is thoroughly filled with the adhesive.
(7) A terminal-equipped electric wire includes a terminal having a core wire crimp section; an electric wire whose core wires are crimped to the core wire crimp section; a heat shrinkable tube that covers the core wire crimp section; and an adhesive that is provided in the heat shrinkable tube and solidified so as to close an opening of a terminal-side one tube end with a closed surface orthogonal to an axis of the heat shrinkable tube.
In the terminal-equipped electric wire having the configuration described in connection with (7), the terminal-side opening of the heat shrinkable tube that covers the core wire crimp section is closed with the closed surface orthogonal to the axis of the heat shrinkable tube made of the solidified adhesive. Accordingly, the one tube end can be closed up to its open end with a sufficient volume of adhesive. Thus, the one tube end filled with the adhesive can be placed in close proximity to the electrical contact. A length of the terminal from the electrical contact to the other tube end can be shortened by an amount corresponding to the distance over which the one tube end is made close to the electrical contact.
The heat shrinkable tube mount method and the heat shrinkable tube mounting jig of the invention make it possible to reliably fix the heat shrinkable tube without involvement of an adhesive leakage, so that the heat shrinkable tube positioned in close proximity to the electrical contact can be filled up to its open end with the adhesive.
Further, the length of the terminal-equipped electric wire of the invention can be shortened by an amount corresponding to the distance from the terminal to the tube other end.
The invention has been briefly described thus far. Details of the invention will be more clarified by reading through a mode for implementing the invention (hereinafter called an “embodiment”) to be described below, by reference to the accompanying drawings.
An embodiment of the invention is hereunder described by reference to the drawings.
As shown in
In the embodiment, the terminal 23 is described by taking, as an example, an LA terminal to be connected to a battery placed in an engine room of an automobile, and the like. However, the terminal can be any terminal to be used in another application, so long as the terminal has the core wire crimp section 25 requiring waterproof treatment.
As shown in
The heat shrinkable tube mounting jig 11 is input into an unillustrated heater outfitted with a heating section, along with the outfitted terminal-equipped electric wire 21. The heater is provided with a conveyor belt for conveying the heat shrinkable tube mounting jig 11 to the heating section. Accordingly, the terminal-equipped electric wire 21 outfitted to the heat shrinkable tube mounting jig 11 is conveyed to an interior of the heater by means of the conveyor belt.
As shown in
The lower frame 15 is provided at a front end of the base 13, and a terminal fit recess 49 is formed in an upper surface of the lower frame 15. The terminal fit recess 49 is a rectangular shape that is substantially identical with an outer shape of the terminal 23 of the terminal-equipped electric wire 21, and can restrict in-plane movement of the terminal 23.
A portion of a front-end-side peripheral wall of the terminal fit recess 49 is cut to prevent from interfering with the terminal board 31 of the terminal 23 positioned so as to be capable of fitting. The terminal 23 of the embodiment has a shape such that the terminal board 31 becomes asymmetrical with respect to an axis 81 of the heat shrinkable tube 27 (see
A temporary retention claw 51 is provided on the terminal fit recess 49 on an upper surface of the base 13. As shown in
A dam wall 53 is formed on a front-end edge of the lower frame 15. A one tube end 55 (see
The front-end edge of the upper frame 17 is provided with a tube fixing claw 59 that projects in a direction parallel to the electric wire 41. The tube fixing claw 59 pinches a portion 61 (see
The clamp lever 19 that is turned to a pinching position where the clamp lever 19 pinches the lower frame 15 and the upper frame 17 is provided on a side of the base 13 in a turnable manner. A pair of parallel pinching pieces 65 (see
A plate 67 that is to be used for ensuring clearance for filling purpose and be inserted among the plurality of electric wires 41 (two in the embodiment) led out of the heat shrinkable tube 27 is removably provided on the base 13 of the embodiment. The plate 67 is provided on a front-end side of a support lever 69. A base-end side of the support lever 69 is provided with a fixing section 71, and the fixing section 71 is fixedly fastened while the base 13 is sandwiched between the fixing section 71 and the support lever 69. A plurality of positioning grooves 73 for positioning the fixing section 71 are formed in the base 13. As a matter of course, when the electric wire 41 to be connected to the terminal 23 is one, the plate 67 is removed.
When the electric wire 41 is provided in number of two as described in connection with the embodiment, the plate 67 is sandwiched between the electric wires 41 as shown in
In the heat shrinkable tube mounting jig 11 of the embodiment, the terminal board 31 of the terminal 23 is arranged so as to fit to the terminal fit recess 49 in a direction in which the core wire crimp section 25 faces down (see
As shown in
Operation of the heat shrinkable tube mounting jig 11 having the above configuration is now described.
In the heat shrinkable tube mounting jig 11, the terminal board 31 is fitted into the terminal fit recess 49 of the lower frame 15 while the terminal back face 75 is oriented up in such a way that the front-end side edge of the terminal board 31 gets into under the temporary retention claw 51. The electric wires 41 and the core wire crimp section 25, which are led out of the terminal 23 fitted to the terminal fit recess 49, are sheathed with the heat shrinkable tube 27. In the heat shrinkable tube 27, the one tube end 55 is brought into contact with the dam wall 53 of the lower frame 15 (see
In this state, the upper frame 17 is turned, whereupon the terminal 23 becomes fixedly pinched between the lower frame 15 and the upper frame 17. Concurrently, the tube fixing claw 59 projectingly provided on the upper frame 17 is pressed against the portion 61 of the peripheral wall of the one tube end 55. Since the portion 61 of one tube end 55 is pinched between the terminal board 31, which is held between the lower frame 15 and the upper frame 17, and the tube fixing claw 59. Hence, the one tube end 55 can be reliably pinched. An opening 79 (see
The heat shrinkable tube mount method of the embodiment is now described.
In order to mount the heat shrinkable tube 27 to the terminal-equipped electric wire 21 by use of the above-described heat shrinkable tube mounting jig 11, the terminal 23 of the terminal-equipped electric wire 21 is first fitted to the terminal fit recess 49 of the lower frame 15 provided on the base 13 as shown in
On this occasion, as shown in
Next, as shown in
Subsequently, the upper frame 17 joined in a turnable manner to the lower frame 15 by way of the hinge 57 covers the terminal fit recess 49, thereby restricting movement of the terminal 23 in a direction orthogonal to the mount surface 45 of the terminal set table (see
Next, as shown in
The heat shrinkable tube mounting jig 11 holding the terminal 23 is thus input into the unillustrated heater along with the terminal-equipped electric wire 21. As shown in
The terminal-equipped electric wire 21 thus outfitted with the heat shrinkable tube 27 is made up of the terminal 23 having the core wire crimp section 25 (see
As shown in
As a consequence, according to the heat shrinkable tube mount method and the heat shrinkable tube mounting jig 11 of the embodiment, the heat shrinkable tube 27 can be reliably fixed without involvement of leakage of the hot melt 29. It is possible to fill the heat shrinkable tube 27, which is positioned in close proximity to the electrical contact 35, up to its open end with the hot melt 29.
Moreover, the length of the terminal-equipped electrical contact 21 of the embodiment from the electrical contact 35 of the terminal 23 to the remaining tube end 87 can be shortened.
The heat shrinkable tube mount method, the heat shrinkable tube mounting jig, and the terminal-equipped electric wire of the invention are not limited to those described in connection with the embodiment and are susceptible to alterations, modifications, and the like. In addition, materials, geometries, dimensions, locations, and the number of constituent elements described in connection with the embodiment are not restricted and arbitrary, so long as the invention can be accomplished.
The present invention is useful for providing a heat shrinkable tube mount method, a heat shrinkable tube mounting jig, and a terminal-equipped electric wire that make it possible to reliably fix a heat shrinkable tube without involvement of an adhesive leakage and fill the heat shrinkable tube, which is located in close proximity to an electrical contact, up to its open end with an adhesive.
Number | Date | Country | Kind |
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2011-260810 | Nov 2011 | JP | national |
This application is a continuation of PCT application No. PCT/JP2012/081578, which was filed on Nov. 29, 2012 based on Japanese Patent Application (No. 2011-260810) filed on Nov. 29, 2011, the contents of which are incorporated herein by reference.
Number | Date | Country | |
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Parent | PCT/JP2012/081578 | Nov 2012 | US |
Child | 14263485 | US |