WO2019203636A1

WO2019203636A1 - Piercing connector

Info

Publication number: WO2019203636A1
Application number: PCT/NL2019/050039
Authority: WO
Inventors: Petrus Johannes Buijsman
Original assignee: Buysman Holding B.V.
Priority date: 2018-04-19
Filing date: 2019-01-23
Publication date: 2019-10-24
Also published as: NL2020796B1; EP3782230B1; EP3782230A1

Abstract

The invention relates to a piercing connector configured for making an insulation-piercing contact with an electric wire having stranded core and an insulation sheath, wherein the piercing connector comprises a head and at one side thereof a blind insert slot for inserting the electric wire from aside, a shaft with an inner channel in which a wire clamp is enclosed, and a tightening knob around the outer thread with a metal needle that extends through the shaft towards the insert slot, wherein the wire clamp comprises a clamping body with a clamping claw that is slidable through the inner channel between a retracted position and a clamping position, and a protrusion that displaceable with respect to the clamping body wherein the protrusion retracts with respect to the clamping body after a threshold force exerted by the tightening knob on the protrusion is exceeded.

Description

Piercing connector

BACKGROUND

The invention relates to a piercing connector configured for making an insulation-piercing contact with an electric wire having a stranded core and an insulation sheath around it. A known piercing connector of that type comprises a metal contact with cutting teeth in which the electric wire is pressed, whereby the teeth penetrate the sheath to come in electrical contact with the stranded core .

SUMMARY OF THE INVENTION

A disadvantage of the known piercing connector is that the fixation of the electric wire and the penetration of the insulation sheath by the teeth is performed in one operation. When the electric wire is not properly positioned with respect to the metal contact, the electrical contact may be unreliable.

It is an object of the present invention to provide a piercing connector for making an insulation piercing contact with an electric wire having a stranded core and an insulation sheath around it, wherein the electric wire can be properly positioned before it is penetrated. According to a first aspect, the invention provides a piercing connector configured for making an insulation-piercing contact with a first electric wire, wherein the first electric wire comprises a stranded core of electrically conductive material and an insulating sheath of electrically insulating material, wherein the piercing connector comprises a base having an inlay section for the first electric wire and a tightening section, and a tightening knob, wherein the inlay section comprises a head and at one side thereof a blind insert slot for inserting the first electric wire into the head from aside, and wherein the tightening section comprises a shaft with an outer thread and an inner channel in which a clamping mechanism is enclosed, and wherein the tightening knob comprises a hood with an inner thread around the outer thread of the shaft and a metal needle that extends from the hood through the shaft towards the insert slot, and wherein the clamping mechanism comprises a first wire clamp comprising a first clamping body with a first clamping claw that is slidable through the inner channel between a retracted position in which the first electric wire can be inserted in the insert slot, and a clamping position in which the first clamping claw engages the first electric wire inside the insert slot, wherein the first wire clamp comprises a first protrusion that displaceable with respect to the first clamping body between a projecting position in which it is engaged by the tightening knob to move the first wire clamp along with the tightening knob, and a retracted position in which the tightening knob passes the first protrusion and the needle penetrates the insulation sheath, wherein the first protrusion retracts with respect to the first clamping body after a first threshold force exerted by the tightening knob on the first protrusion is exceeded.

The piercing connector according to the invention comprises a head with a blind insert slot for inserting the first electric wire into the head from aside. This allows the piercing connector to be hooked behind the first electric wire to be branched off. This hooking operation can be performed in complex situations, for example when the first electric wire forms part of a bundle of electric wires that is hidden or hardly accessible, whereby the installation of the piercing connector needs to be performed partly blind. After hooking the piercing connector onto the first electric wire, the tightening knob can be rotated whereby the first clamping claw engages the first electric wire inside the insert slot to fixate it properly with respect to the needle. By exceeding the threshold force with the rotating tightening knob, the needle can penetrate the first electric wire while it remains properly positioned with respect to the needle. This makes the piercing connector according to the invention suitable for making a reliable electric connection with the first electric wire in abovementioned complex situations.

In an embodiment the first protrusion extends through and outside a first elongate slot in the shaft, whereby the first protrusion is visible from outside to verify the retracted position of the first clamping claw in preparation of the installation of the piercing connector.

In an embodiment the first wire clamp comprises a first positioner having the first protrusion, wherein the first positioner is rotatable connected to the first clamping body for displacing the first protrusion between the projecting position and the retracted position.

In an embodiment thereof the first positioner comprises a flexible lip with a distal end that is in the projecting position of the first protrusion in abutment with an abutment surface of the first clamping body, wherein the distal end disengages from the abutment surface by bending of the flexible lip when the first threshold force is exerted onto the first protrusion. The disengagement of the distal end from the abutment surface may cause a clicking sound, which can be clearly noticed by the user to verify that the needle pierces the first electric wire.

In an embodiment the first wire clamp comprises two first clamping claws projecting parallel to each other, wherein the needle extends between the two first clamping claws. The two first clamping claws may properly position the first electric wires at both sides of the needle.

In an embodiment thereof the two first clamping claws comprise V-shaped first grippers at their distal ends that center the first electric wire in front of the needle.

In an embodiment the piercing connector is configured for making an insulation-piercing contact with the first electric wire and with a second electric wire, wherein she second electric wire comprises a stranded core of electrically conductive material and an insulating sheath of electrically insulating material, wherein the piercing connector comprises an insert section for the second electric wire, wherein the insert section comprises an insert hole in the base for insertion of the electric wire, and wherein the clamping mechanism comprises a second wire clamp comprising a second clamping body with a second clamping claw that is slidable through the inner channel between a retracted position in which the second electric wire can be inserted in the insert hole, and a clamping position in which the second clamping claw engages the second electric wire behind the insert hole, wherein the second wire clamp comprises a second protrusion that displaceable with respect to the second clamping body between a projecting position in which it is engaged by the tightening knob to move the second wire clamp along with the tightening knob, and a retracted position in which the tightening knob passes the second protrusion and the needle penetrates the insulation sheath, wherein the second protrusion retracts with respect to the second clamping body after a second threshold force exercised by the knob on the second protrusion is exceeded.

The piercing connector according to this embodiment can be installed in two stages, wherein firstly the end of second electric wire is inserted in the insert hole to be connected to the piercing connector, where after the piercing connector is connected to the first electric wire as described before.

In an embodiment thereof is in the projecting positions the second protrusion located closer to the tightening knob than the first protrusion, whereby the second wire clamp is activated by the tightening knob and subsequently the first wire clamp is operated.

In an embodiment the second protrusion extends through and outside a second elongate slot in the shaft, whereby the second protrusion is visible from outside to verify the retracted position of the second clamping claw in preparation of the installation of the piercing connector .

In an embodiment the second wire clamp comprises a second positioner having the second protrusion, wherein the second positioner is rotatable connected to the second clamping body for displacing the second protrusion between the projecting position and the retracted position.

In an embodiment thereof the second positioner comprises a flexible lip with a distal end that is in the projecting position of the second protrusion in abutment with an abutment surface of the second clamping body, wherein the distal end disengages from the abutment surface by bending of the flexible lip when the second threshold force is exerted onto the second protrusion. The disengagement of the distal end from the abutment surface may cause a clicking sound, which can be clearly noticed by the user to verify that the needle pierces the second electric wire.

In an embodiment the second wire clamp comprises two second clamping claws projecting parallel to each other, wherein the needle extends between the two second clamping claws. The two second clamping claws may properly position the second electric wires at both sides of the needle .

In an embodiment thereof the two second clamping claws comprise V-shaped second grippers at their distal ends that center the second electric wire in front of the needle.

In a compact embodiment the first wire clamp and the second wire clamp are at least partially inserted into each other and are slidable with respect to each other.

In an embodiment the first protrusion and the second protrusion extend at opposite sides of the shaft.

The various aspects and features described and shown in the specification can be applied, individually, wherever possible. These individual aspects, in particular the aspects and features described in the attached dependent claims, can be made subject of divisional patent applications .

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be elucidated on the basis of an exemplary embodiment shown in the attached drawings, in which :

Figures 1A and IB are an isometric back view and an isometric front view of a piercing connector according to an embodiment of the invention;

Figures 2A and 2B are an isometric view and a top view of a partial longitudinal cut of the piercing connector as shown in figure IB to show an internal clamping mechanism thereof; and

Figures 3A and 3B are isometric views of the internal clamping mechanism, respectively shown in assembled and partially disassembled form for illustrative purposes only. DETAILED DESCRIPTION OF THE INVENTION

Figures 1A and IB show a piercing connector 1 according to the invention for making an insulation- displacement contact (IDC) or insulation-piercing contact (IPC) with a first electric wire 2 and a second electric wire 3. These electric wires 2, 3 each comprise a stranded core 4 of electrically conductive material, such as copper, and an outer sheath 5 of electrically insulating material, such as a plastic, whereby the electric wires 2, 3 are flexible and easily to configure. The first electric wire 2 may form part of a bundle of parallel electric wires, while the second wire 2 electrically branches off from the first electric wire 2.

The bundle of electric wires may form part of a cable tree of a vehicle, such as a truck, wherein the first wire 2 conducts electrical signals that need to be monitored by a retrofit monitoring device. This monitoring device may for example monitor the speed of the truck, the position of the gas valves of the engine, or the global position of the truck as provided by the on board navigation system to optimize the performance of the truck and the human driver. The cable tree of a vehicle is usually hidden behind the dashboard or by behind shields inside the engine department and is therefore hard to branch off. The piercing connector 1 according to the invention is designed to make a reliable electrical conductive branch from the first electric wire 2 in such complex configurations.

The piercing connector 1 comprises a plastic base 10 having along its center line A an inlay section 20 for the first electric wire 2, an insert section 30 for the second electric wire 3, a hand gripping section 40, and a tightening section 50 around which a tightening knob 60 of the piercing connector 1 is screwed.

The inlay section 20 comprises a partially hollow head 21 with a frusto conical outer wall 22 forming a distal end 23 of the piercing connector 1. The head 21 comprises as from one side a blind insert slot or insert mouth 24 that extends inwardly beyond the center line A and that extends obliquely upwards with respect to the center line A towards the distal end 23. The inlay section 20 comprises a needle exit hole 16 and a flind needle receiving hole 27 on the center line A that debouch into the mouth 24. The frusto conical outer wall 22 allows the piercing connector 1 to be inserted in abovementioned bundle of parallel electric wires, wherein the first electric wire 2 that forms part thereof and that is to be connected is hooked inside the insert mouth 24. By slightly retracting the piercing connector 1 the first electric wire 2 is urged to reach the bottom of the insert mouth 24 so as to intersect the center line A.

The insert section 30 comprises a straight cylindrical outer wall 31 which is a continuation of the frusto conical outer wall 22, and one insert hole 32 for the second electric wire 3. As best shown in figures 2A and 2B, the insert section 30 comprises at the opposite side of the insert hole 32 with respect to the center line A, an extension 33 that protrudes from and that merges into the outer wall 31. The extension 33 has an insert channel 34 that tapers in the direction away from the center line A to receive the distal end of the second electrical wire 3. The insert section 30 is hollow to allow the second electric wire 3 that is inserted through the insert hole 32 to hit the opposite side of the outer wall 31, wherein it intersects the center line A.

The hand gripping section 40 comprises a gripping ring 41 having a diameter that is larger than the diameter of the inlay section 20 and the insert section 30. The gripping ring 41 is provided with gripping grooves 42 around its perimeter.

The tightening section 50 comprises an elongate shaft 51 that is provided with an external thread 52 and an internal channel 53 with a rectangular cross section that are aligned with the center line A. The internal channel 53 is accessible through an elongate first slot 54 and an elongate second slot 55 that are oppositely located with respect to the center line A and that extend parallel to the center line A. As best shown in figure 2A, the internal channel 53 slidably accommodates a plastic clamping mechanism 70 that is described in more detail hereafter.

As shown in figures 2A and 2B, the tightening knob 60 comprises a plastic hood 61 with external gripping grooves 63 and a circumferential edge 64 that faces the 40. The tightening knob 60 comprises an internal thread 62 that fits around the external thread 52 of the tightening section 50, and a circumferential edge that faces the inlay section 20. The tightening knob 60 comprises a needle 66 with a sharp point 67 that is mounted to the inner side of the hood 61 and that extends along the center line A through the clamping mechanism. The needle 66 is made of electrically conductive material, such as steel.

The clamping mechanism 70 comprises a first wire clamp 71 for the first electrical wire 2 and a second wire clamp 72 for the second electrical wire 3 that are both enclosed in the inner channel 53 of the tightening section 50. The wire clamps 71, 72 are slidable inside the inner channel 53 in the respective directions B, C parallel to the center line A. As best shown in figure 3A, the second wire clamp 72 is placed above and partially into the first wire clamp 71. In figure 3B the second wire clamp 72 is shown while it is taken out and rotated upside for illustrative purposes, solely to show the details thereof at the side that faces the first wire clamp 71.

As best shown in figure 3B, the first wire clamp 71 comprises a first clamping body 73 having two plate shaped first clamping claws 74 that extend parallel and spaced apart from each other. The first clamping claws 74 each comprise an elongate slot 75 to allow free passage of the second electric wire 3 when inserted via the insert hole 32 of the first wire clamp 71 in each sliding position in direction B. At the distal ends the first clamping claws 74 comprise V-shaped first grippers 76. Depending on its sliding position in direction B, the first clamping claws 74 are fully retracted from the insert mouth 24 of the inlay section 20 or they project via slits 25 of the inlay section 20 into the insert mouth 24 to engage and confine the sheath 5 of the first electric wire 2 with its grippers 76 inside the insert mouth 24.

The first wire clamp 71 comprises a first positioner 78 that is rotatable around a first axis 77 of the clamping body 73. The first positioner 78 comprises a first protrusion 79 that protrudes from the clamping body 73 through and outside the first slot 54 of the tightening section 50, and a first flexible lip 80 and a second flexible lip 81 that both engage a first abutment surface

82 and a second abutment surface 83 of the first clamping body 73 that are located at opposite sides of the first axis 77. These opposite engagements ensure that the first protrusion 79 remains in its projecting position. When a force D above a predetermined first threshold force is applied onto the first protrusion 79 parallel to the center line A towards the first clamping claws 74, the second flexible lip 81 disengages from the second abutment surface

83 and flexes towards the first axis 77 to elastically jump over to a third abutment surface 84 of the first clamping body 73, and the first positioner 78 is rotated around the first axis 77 to retract the first protrusion 79 behind the external thread 52 and into the first clamping body 73.

As best shown in figure 3B, the second wire clamp 72 comprises a second clamping body 93 having two plate shaped second clamping claws 94 that extend parallel and spaced apart from each other. At the distal ends the second clamping claws 94 comprise V-shaped second grippers 96. Depending on its sliding position in direction C, the second clamping claws 94 are fully retracted with respect to the insert hole 32 for the second electric wire 3, or they engage the sheath 5 of the inserted second electric wire 3 inside the inlay section 20.

The second wire clamp 72 comprises a second positioner 98 that is rotatable around a second axis 97 of the second clamping body 73. The second positioner 98 comprises a second protrusion 99 that protrudes from the second clamping body 93 through and beyond the second slot 55 of the tightening section 50, and a first flexible lip 100 and a second flexible lip 101 that both engage a first abutment surface 102 and a second abutment surface 103 of the second clamping body 93 that are located at opposite sides of the axis 77. These opposite engagements ensure that the second protrusion 99 remains in its projecting position. When a force E above a predetermined second threshold force is applied onto the second protrusion 99 parallel to the center line A in the direction of the second clamping claws 94, the second flexible lip 101 disengages from the second abutment surface 103 and flexes towards the second axis 97 to elastically jump over to a third abutment surface 104 of the second clamping body 93, and the second positioner 98 is rotated around the second axis 97 to retract the second protrusion 99 behind the external thread 52 and into the second clamping body 93.

The first clamping body 73 and the second clamping body 93 both comprise a slots 85, 105 that together define a passage for the needle 66. In the initial position of the piercing connector 1 as shown in the figures, the point 67 of the needle 66 is located retracted from the passage for the second electric wire 3 as defined by the insert hole 32 thereof. Both the first protrusion 79 and the second protrusion 99 extend at the beginning of their respective first slot 54 and second slot 55, wherein the first grippers 76 are fully retracted from the insert mouth 24 of the inlay section 20 and the second grippers 96 are fully retracted with respect to the insert hole 32 of the insert section 30. In this initial position the second protrusion 99 is located closer to the tightening knob 60 than the first protrusion 79. When an electrical contact is made between the first electric wire 2 and the second electric wire 3, firstly the end of the second electric wire 3 having the core 4 protected by the sheath 5 is inserted in the piercing connector 1 via the insert hole 32 until it wherein it subsequently enters the tapering insert channel 34. Due to the tapering shape the distal ends becomes tightly confined inside the insert channel 34 without reaching the bottom of the blind insert channel 34. By this confinement the second electric wire 3 is closed off watertight. Subsequently the tightening knob 60 is rotated whereby its circumferential edge 64 pushes the second wire clamp 72 towards the second electric wire 3 until the second electric wire 3 becomes confined between the second grippers 96 and the insert section 30. By rotating the tightening knob 60 further, the second protrusion 99 is pushed with the force E above the threshold force, whereby the second protrusion 99 retracts and the point 67 of the needle 66 fully penetrates the properly aligned sheath 5 and the core 4 of the second electrical wire 3. The second electrical wire 3 is then firmly mounted to the piercing connector 1. As the needle 66 penetrates the flexible sheath 5 of the second wire 3 with its sharp point 67, the sheath 5 surrounds the needle 66 tightly whereby a watertight connection with the core 4 is obtained.

In this condition the piercing connector 1 can be inserted in the bundle of electric wires of which the first electrical wire 3 forms part. After the first electrical wire 2 is hooked into the insert mouth 24, the tightening knob 60 is rotated further whereby its circumferential edge 64 pushes the first wire clamp 71 towards the first electric wire 2 until it becomes confined between the first grippers 76 and the inlay section 20. By rotating the tightening knob 60 further, the first protrusion 79 is pushed with the force D above the first threshold force, whereby the first protrusion 79 retracts and the point 67 of the needle 66 exits via the needle exit hole 16 inside the insert mouth 24 to fully penetrate the properly aligned sheath 5 and the core 4 of the second electrical wire 3. As the needle 66 penetrates the flexible sheath 5 of the first wire 3 with its sharp point 67, the sheath 5 surrounds the needle 66 tightly whereby a watertight connection with the core 4 is obtained. Finally the sharp point 67 enters the needle receiving hole 27 for sideward stabilization of the needle 26. The first electrical wire 2 is then firmly mounted to the piercing connector 1, and an electrical connection between the cores 4 of the first electric wire 2 and the second electric wire 3 is made by the metal needle 66.

It is to be understood that the above description is included to illustrate the operation of the preferred embodiments and is not meant to limit the scope of the invention. From the above discussion, many variations will be apparent to one skilled in the art that would yet be encompassed by the scope of the present invention.

Claims

C L A I M S

1. Piercing connector configured for making an insulation-piercing contact with a first electric wire, wherein the first electric wire comprises a stranded core of electrically conductive material and an insulating sheath of electrically insulating material, wherein the piercing connector comprises a base having an inlay section for the first electric wire and a tightening section, and a tightening knob, wherein the inlay section comprises a head and at one side thereof a blind insert slot for inserting the first electric wire into the head from aside, and wherein the tightening section comprises a shaft with an outer thread and an inner channel in which a clamping mechanism is enclosed, and wherein the tightening knob comprises a hood with an inner thread around the outer thread of the shaft and a metal needle that extends from the hood through the shaft towards the insert slot, and wherein the clamping mechanism comprises a first wire clamp comprising a first clamping body with a first clamping claw that is slidable through the inner channel between a retracted position in which the first electric wire can be inserted in the insert slot, and a clamping position in which the first clamping claw engages the first electric wire inside the insert slot, wherein the first wire clamp comprises a first protrusion that displaceable with respect to the first clamping body between a projecting position in which it is engaged by the tightening knob to move the first wire clamp along with the tightening knob, and a retracted position in which the tightening knob passes the first protrusion and the needle penetrates the insulation sheath, wherein the first protrusion retracts with respect to the first clamping body after a first threshold force exerted by the tightening knob on the first protrusion is exceeded .

2. Piercing connector according to claim 1, wherein the first protrusion extends through and outside a first elongate slot in the shaft.

3. Piercing connector according to claim 1 or 2, wherein the first wire clamp comprises a first positioner having the first protrusion, wherein the first positioner is rotatable connected to the first clamping body for displacing the first protrusion between the projecting position and the retracted position.

4. Piercing connector according to claim 3, wherein the first positioner comprises a flexible lip with a distal end that is in the projecting position of the first protrusion in abutment with an abutment surface of the first clamping body, wherein the distal end disengages from the abutment surface by bending of the flexible lip when the first threshold force is exerted onto the first protrusion .

5. Piercing connector according to any one of the preceding claims, wherein the first wire clamp comprises two first clamping claws projecting parallel to each other, wherein the needle extends between the two first clamping claws.

6. Piercing connector according to claim 5, wherein the two first clamping claws comprise V-shaped first grippers at their distal ends that center the first electric wire in front of the needle.

7. Piercing connector according to any one of the preceding claims, configured for making an insulation piercing contact with the first electric wire and with a second electric wire, wherein the second electric wire comprises a stranded core of electrically conductive material and an insulating sheath of electrically insulating material, wherein the piercing connector comprises an insert section for the second electric wire, wherein the insert section comprises an insert hole in the base for insertion of the electric wire, and wherein the clamping mechanism comprises a second wire clamp comprising a second clamping body with a second clamping claw that is slidable through the inner channel between a retracted position in which the second electric wire can be inserted in the insert hole, and a clamping position in which the second clamping claw engages the second electric wire behind the insert hole, wherein the second wire clamp comprises a second protrusion that displaceable with respect to the second clamping body between a projecting position in which it is engaged by the tightening knob to move the second wire clamp along with the tightening knob, and a retracted position in which the tightening knob passes the second protrusion and the needle penetrates the insulation sheath, wherein the second protrusion retracts with respect to the second clamping body after a second threshold force exercised by the knob on the second protrusion is exceeded.

8. Piercing connector according to claim 7, wherein in the projecting positions the second protrusion is located closer to the tightening knob than the first protrusion .

9. Piercing connector according to claim 7 or 8, wherein the second protrusion extends through and outside a second elongate slot in the shaft.

10. Piercing connector according to any one of the claims 7-9, wherein the second wire clamp comprises a second positioner having the second protrusion, wherein the second positioner is rotatable connected to the second clamping body for displacing the second protrusion between the projecting position and the retracted position.

11. Piercing connector according to claim 10, wherein the second positioner comprises a flexible lip with a distal end that is in the projecting position of the second protrusion in abutment with an abutment surface of the second clamping body, wherein the distal end disengages from the abutment surface by bending of the flexible lip when the second threshold force is exerted onto the second protrusion .

12. Piercing connector according to any one of the preceding claims, wherein the second wire clamp comprises two second clamping claws projecting parallel to each other, wherein the needle extends between the two second clamping claws.

13. Piercing connector according to claim 12, wherein the two second clamping claws comprise V-shaped second grippers at their distal ends that center the second electric wire in front of the needle.

14. Piercing connector according to any one of the claims 7-13, wherein the first wire clamp and the second wire clamp are at least partially inserted into each other and are slidable with respect to each other.

15. Piercing connector according to any one of the claims 7-14, wherein the first protrusion and the second protrusion extend at opposite sides of the shaft.

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FG/HZ