EP0992088B1

EP0992088B1 - A patch cable and connector assembly, and a method for manufacturing the same

Info

Publication number: EP0992088B1
Application number: EP97933080A
Authority: EP
Inventors: Björn HOLMSTRÖM
Original assignee: Interconnect AB
Current assignee: Interconnect AB
Priority date: 1997-06-26
Filing date: 1997-06-26
Publication date: 2001-11-28
Anticipated expiration: 2017-06-26
Also published as: DE69708694D1; MXPA00000069A; ES2167006T3; JP2001508927A; WO1999000879A1; EP0992088A1; NO996431D0; CA2295078A1; PL337737A1; NO317374B1; ATE209830T1; AU3636897A; DE69708694T2; PL184853B1; NO996431L; PT992088E

Abstract

The present invention relates to a patch cable and connector assembly, and a method for manufacturing the same. The assembly (30) comprises a patch cable (32) comprising a number of conductors (34), wherein each conductor (34) is surrounded by an insulation, and a jacket (36) surrounding all the conductors (34) with their insulations, wherein the jacket (36) is stripped off a predetermined distance from at least one end of the patch cable (32). The assembly (30) also comprises a connector (38) comprising a strain relief, and a number of connection pins, wherein each conductor (34) is connected to a connection pin. The strain relief of the connector (38) is not activated. The assembly (30) also comprises a moulded device (40) which has filled up the space between the connector (38) and the conductors (34) and also surrounds the transition (42) between the patch cable (32) with jacket (36) and the patch cable (32) with the jacket (36) stripped off, in such a way that the conductors (34) are not clamped and the device (40) functions as a mechanically stable strain relief.

Description

Technical field of the invention

The present invention relates to a patch cable and connector assembly. The present invention also relates to a method for manufacturing a patch cable and connector assembly.

Description of related art

The patch cable and connector assemblies used today have an activated strain relief which presses the cable itself extremely hard. See for ex. document US-A-4.697.339. If the conductors in the cable are close to each other, this means that they can be further compressed under high pressure, flattening out the insulation and bringing the conductors too close to each other. The result will be cross talk, and the NEXT value is degraded. One of the major problems with this is that the effect may not be immediately apparent, as the plastic of the insulation is "cold flowing", i.e. it takes time for the effect to occur. Another disadvantage with this type of patch cable is that the risk of short circuiting increases when the insulations enclosing the conductors have been cracked due to compression. These disadvantages will be even more apparent and troublesome when the operating frequency is increasing,. Tomorrow's information highway is already here, operating at speeds up to 100 MHz for patch cables of "Category 5". The development will increase, not decrease, the operating frequency even more. So these problems will be highlighted even more in the future.

Summary of the invention

The object of the present invention is to solve the above mentioned problems. This object is achieved with a method of manufacturing a patch cable and connector assembly according to Claim 1, and with a patch cable and connector assembly according to Claim 5. The assembly comprises a patch cable comprising a number of conductors, wherein each conductor is surrounded by an insulation, and a jacket surrounding all the conductors with their insulations, and a connector comprising a strain relief, and a number of connection pins. The method according to the invention comprises the following steps:

to strip off the jacket a predetermined distance from at least one end of the patch cable;
to assemble the patch cable and the connector, connecting each conductor with a connection pin, without activating the strain relief;
to fix the assembled patch cable and connector in a moulding means intended for moulding; and
to mould, with the aid of the moulding means, a device which fills up the space between the connector and the conductors and also surrounds the transition between the patch cable with jacket and the patch cable with the jacket stripped off, in such a way that the conductors are not clamped and the device functions as a mechanically stable strain relief. The main advantage with the method according to the present invention is that the conductors are not clamped and that they run without restrictions up to the connection pins. Another advantage with the method according to the present invention is that the moulded device gives rise to a bending radius between the connector and the patch cable with the jacket.

The moulding means comprises a lower part and an upper part, a holding fixture and two bar halves. Advantageously, the fixation step of the method comprises the steps:

to push the connector into a hole in the holding fixture for fixating of the front part of the assembly;
to place the patch cable with jacket into a recess in each bar half; and
to assemble the lower part to the upper part with the holding fixture and the bar halves arranged therebetween, resulting in a mould.

The moulding means comprises also a filler tube connected to at least one mould in the moulding means. Preferably, the moulding step of the method comprises the steps:

to pour melted cast compound into the filler tube to be distributed to one mould for each patch cable; and
to disassemble the moulding means when the cast compound has solidified.

Advantageously, the cast compound is a plastic material.

Another object of the invention is to provide a patch cable and connector assembly. The assembly comprises a patch cable comprising a number of conductors, wherein each conductor is surrounded by an insulation, and a jacket surrounding all the conductors with their insulations, wherein the jacket is stripped off a predetermined distance from at least one end of the patch cable. The assembly also comprises a connector comprising a strain relief, and a number of connection pins, wherein each conductor is connected to a connection pin. The strain relief of the connector is not activated. The assembly also comprises a moulded device which has filled up the space between the connector and the conductors and also surrounds the transition between the patch cable with jacket and the patch cable with the jacket stripped off, in such a way that the conductors are not clamped and the device functions as a mechanically stable strain relief. The main advantage with the assembly according to the present invention is that the conductors are not clamped and that they run without restrictions up to the connection pins. This will guarantee a patch cable and connector assembly with high performance. A performance which will not degrade with time.

Advantageously, the moulded device is integral, giving rise to a bending radius between the connector and the patch cable with the jacket. This prevents that the cable can be sharply bent where it enters the conductor, where this bend can result in a deterioration of about 2 dB in cross stalk performance, degrading signal quality and slowing down the general network performance.

Preferably, the moulded device is made of a plastic material.

Brief description of the Drawings

Figure 1 is a cross.-sectional view of a patch cable and connector assembly according to the state of the art;

Figure 2 is another cross-sectional view of the assembly according to figure 1;

Figure 3 is a cross-sectional view of a patch cable and connector assembly according to the present invention;

Figure 4 is another cross-sectional view of the assembly according to figure 3;

Figure 5a, shows a side view of the lower part and upper part of the moulding means;

Figure 5 b, shows a side view of the moulding means; and

Figure 6 is a flow chart of the method according to the present invention.

Detailed description of Embodiments

In figure 1 there is disclosed a cross-sectional view of a patch cable and connector assembly according to the state of the art. The assembly 10 comprises a patch cable 12 comprising a number of conductors 14, wherein each conductor 14 is surrounded by an insulation (not disclosed), and a jacket 16 surrounding all the conductors 14 with their insulations. The assembly (10) also comprises a connector 18 comprising a strain relief 20, which is activated. This means that the strain relief 20 presses the conductors 14 extremely hard. If the conductors 14 are close to each other, this means that they can be further compressed under high pressure, flattening out the insulation and bringing the conductors 14 too close to each other (see figure 2). One result of this is cross talk. Another difficulty with this problem is that the effect may not be immediately apparent as the plastic of the insulation cold flows, i.e. it takes time for the effect to occur.

In figure 2 there is disclosed another cross-sectional view of the assembly 10 according to figure 1. In this figure there is clearly disclosed the effect of an activated strain relief. The activated strain relief presses and cuts into the patch cable. The conductors 14 are being pressed under high pressure and are being deformed, whereby the insulation 22 surrounding the conductors 14 being cracked. The risk of short circuit is significant between conductor A and conductor B due to the fact that the insulations surrounding these conductors A, B have been completely cracked. The situation will become worse when time goes on, due to the fact that plastic is a material that cold flows.

In figure 3 there is disclosed a cross-sectional view of a patch cable and connector assembly according to the present invention. The assembly 30 comprises a patch cable 32 comprising a number of conductors 34, wherein each conductor 34. is surrounded by an insulation (not disclosed), and a jacket 36 surrounding all the conductors 34 with their insulations. The assembly 30 also comprises a connector 38 comprising a not activated strain relief (not disclosed). As is disclosed in the figure 3 the jacket 36 is stripped off a predetermined distance from at least one end of the patch cable. The connector 38 also comprises a number of connection pins (not disclosed), wherein each conductor 34 is connected to a connection pin. The assembly 30 also comprises a moulded device 40 which has filled up the space between the connector 38 and the conductors 34 and also surrounds the transition 42 between the patch cable 32 with jacket 36 and the patch cable with the jacket 36 stripped off. In this way the conductors 34 are not clamped and the device 40 functions as a mechanically stable strain relief. The moulded device 40 is integral, giving rise to a bending radius between the connector 38 and the patch cable 32 with the jacket 36. Without this feature, the cable could be sharply bent where it enters the connector, resulting in a deterioration of about 2 dB in cross talk performance, degrading signal quality and slowing down the general network performance. The moulded device 40 is preferably made of a plastic material.

In figure 4 there is disclosed another cross-sectional view of the assembly according to figure 3. The strain relief included in the connector is not activated. Instead the moulded device 40 surrounds the patch cable 32 comprising the jacket 36 and the conductors 34, wherein each conductor 34 is surrounded by an insulation 44. As is clearly disclosed the conductors 34 are not compressed and they run without restriction right up to the connection pins (not disclosed; see figure 3). The moulded device 40 will give a very stable mechanical strain relief.

In figure 5a, there is disclosed a side view of the lower part and the upper part of the moulding means. The moulding means 50 is intended for moulding the device 40 (see figures 3 and 4) and comprises a lower part 52 and an upper part 54, a holding fixture 56 and two bar halves 58₁, 58₂. The lower part 52 and the upper part 54 both comprise a number of (in this case 2) recesses 60₁, 60₂, 62₁, 62₂. In figure 5b, there is disclosed a side view of the moulding means 50 disclosed in figure 5a. In figure 5b, there is also disclosed a filler tube 64 which has connection to the recesses 60₁, 60₂, 62₁, 62₂. When the moulding means 50 is used one connector is pushed into a hole (disclosed with dashed lines) in the holding fixture 56 for fixation of the front part of the assembly. Then the patch cable with jacket is placed into recesses 66₁, 66₂, 68₁, 68₂ in the two bar halves 58₁, 58₂. Then the lower part 52 is assembled with the upper part 54 with the holding fixture 56 and the bar halves 58₁, 58₂ arranged therebetween. This results in two moulds, each of which is intended for producing a device 40 (see figures 3 and 4). Then melted cast compound is poured into the filler tube 64 to be distributed to the recesses 60₁, 60₂, 62₁, 62₂, giving rise to two patch cable and connector assemblies with moulded devices.

In figure 6 there is disclosed a flow chart of the method according to the present invention. The method for manufacturing a patch cable and connector assembly according to the invention starts at block 70. Thereafter, at block 72, the method continues with the step: to strip off the jacket a predetermined distance from at least one end of the patch cable. Then, at block 74, the patch cable and connector are assembled, connecting each conductor with a connection pin, without activating the strain relief. Then, at block 76, the assembled patch cable and connector are fixed in a moulding means intended for moulding. Then, at block 78, with the aid of the moulding means, a device is moulded which fills up the space between the connector and the conductors and also surrounds the transition between the patch cable with jacket and the patch cable with jacket stripped off, in such a way that the conductors are not clamped and the device functions as a mechanically stable strain relief. Then, at block 80, the method is finished. The fixation step 76 comprises the steps:

to push the connector into a hole in the holding device for fixation of the front part of the assembly;
to place the patch cable with jacket into a recess in each bar half; and
to assemble the lower part to the upper part with the holding fixture and the bar halves arranged therebetween, resulting in a mould. The moulding step 78 comprises the steps:

to pour melted cast compound into the filler tube to be distributed to one mould for each patch cable; and
to disassemble the moulding means when the cast compound has solidified. The cast compound is preferably a plastic material.

The invention is not limited to the embodiments described in the foregoing. It will be obvious that many different modifications are possible within the scope of the following claims.

Claims

A method of manufacturing a patch cable and connector assembly (30), wherein the assembly (30) comprises a patch cable (32) comprising a number of conductors (34), wherein each conductor (34) is surrounded by an insulation, and a jacket (36) surrounding all the conductors (34) with their insulations, and a connector (38) comprising a strain relief, and a number of connection pins, wherein the method comprises the steps;

to strip off the jacket (36) a predetermined distance from at least one end of the patch cable (32); and wherein the method is characterized in that it also comprises the steps:

to assemble the patch cable (32) and the connector (38), connecting each conductor (34) with a connection pin, without activating the strain relief;

to fix the assembled patch cable (32) and connector (38) in a moulding means (50) intended for moulding; and

to mould, with the aid of the moulding means (50), a device (40) which fills up the space between the connector (38) and the conductors (34) and also surrounds the transition (42) between the patch cable (32) with jacket (36) and the patch cable (32) with the jacket (36) stripped off, in such a way that the conductors (34) are not clamped and the device (40) functions as a mechanically stable strain relief.
A method according to Claim 1, wherein the moulding means (50) comprises a lower part (52) and an upper part (54), a holding fixture (56) and two bar halves (58₁, 58₂), wherein the method is characterized in that the fixation step comprises the steps:

to push the connector (38) into a hole in the holding fixture (56) for fixating of the front part of the assembly (30);

to place the patch cable (32) with jacket (36) into a recess (66₁, 66₂, 68₁, 68₂) in each bar half (58₁, 58₂) ; and

to assemble the lower part (52) to the upper part (54) with the holding fixture (56) and the bar halves (58₁, 58₂) arranged therebetween, resulting in a mould.
A method according to Claim 2, wherein the moulding means (50) also comprises a filler tube (64) connected to at least one mould in the moulding means (50), wherein the method is characterized in that the moulding step comprises the steps:

to pour melted cast compound into the filler tube (64) to be distributed to one mould for each patch cable; and

to disassemble the moulding means (50) when the cast compound has solidified.
A method according to Claim 3, characterized in that the cast compound is a plastic material.
A patch cable and connector assembly (30) manufactured according to the method according to Claims 1-4, wherein the assembly (30) comprises a patch cable (32) comprising a number of conductors (34), wherein each conductor (34) is surrounded by an insulation, and a jacket (36) surrounding all the conductors (34) with their insulations, wherein the jacket (36) is stripped off a predetermined distance from at least one end of the patch cable (32), and a connector (38) comprising a strain relief, and a number of connection pins, wherein each conductor (34) is connected to a connection pin, characterized in that the strain relief of the connector (38) is not activated, and in that the assembly (30) also comprises a moulded device (40) which has filled up the space between the connector (38) and the conductors (34) and also surrounds the transition (40) between the patch cable (32) with jacket (36) and the patch cable (32) with the jacket (36) stripped off, in such a way that the conductors (34) are not clamped and the device (40) functions as a mechanically stable strain relief.
A patch cable and connector assembly (30) according to Claim 5, characterized in that the moulded device (40) is integral, giving rise to a bending radius between the connector (38) and the patch cable (32) with the jacket (36).
A patch cable and connector assembly according to Claim 6, characterized in that the moulded device (40) is made of a plastic material.