GB2030544A - Packing of electric or electronic components - Google Patents

Abstract

An adapter for facilitating packing of DIL encapsulated components in smaller packing tubes than those generally used is of generally trapezoidal cross-section, similar to the packing tubes, but increases progressively in cross-sectional area from one end to the other end. The larger end has the dimensions of a packing tube as generally used. The smaller end is dimensioned to closely surround a smaller packing tube. Stops (27) limit entry of a tube into the adaptor. Fitting of adapters to the ends of smaller packing tubes enables these tubes to be handled by machinery intended for the larger tubes currently in use. <IMAGE>

Description

SPECIFICATION Packing of electric or electronic components The present invention relates to the packing of DIL (dual-in-line) encapsulated electric or electronic components.

In the electronics industry it is often necessary to pack and transport large numbers of electric or electronic devices encapsulated in the so-called DIL encapsulation, the majority being integrated circuits (I.C.'s). The DIL encapsulation consists of a fairly flat rectangular body in which the I.C. or other component(s) is encapsulated, with short connecting leads or pins descending from the two longer sides of the encapsulation. There are usually eight, fourteen or sixteen leads (or spaces corresponding thereto) per l.C.

To pack and transport these DIL encapsulated components there are currently provided hollow elongate packing tubes of substantially trapezoidal section with a rectangular section projection extending into the volume of the tube from the longer of the parallel sides. The tubes are filled with a number of DIL encapsulated components placed in the tube end to end. The components straddle the projection with the lower surface of their encapsulation bodies resting on it. Once the tube is full the encapsulated components are retained in the tube for transit by pins pushed through aligned holes at each end of the tube.

These tubes are commonly manipulated by machine. Existing machines are constructed to handle a particular size of tube, yet the dimensions of the DIL encapsulated components are often such that they do not utilize all the space within the tubes currently used.

The present invention seeks to enable tubes of smaller cross-section to be used without requiring alteration of existing machinery. Smaller tubes are of advantage in that the filled tubes are often airfreighted, and reduction of bulk and weight is important in reducing transport costs. Less plastics material is required for production of smaller tubes which gives a further saving in costs, especially if an expensive anti-static plastics material is being employed.

According to the present invention there is provided an adaptor for the ends of packing tubes for dual-in-line encapsulated components, said tubes being hollow, elongate and of uniform cross-section which includes an internal projection to be straddled by the components, the adapter being generally tubular and consisting of a first portion to be sleeved over one end of a packing tube, and a second portion to project from the end thereof, at least part of said first portion having an internal cross-section of dimensions to closely surround at least part of said packing tube, and at least a region of said adapter having a cross-section whose external outline is substantially trapezoidal and of larger area than the cross-section of said packing tube, the adapter being provided internally with stops to abut the end of the packing tube and so limit the entry of the packing tube into the adapter. Such adapters can be used to permit tubes to which they are fitted to be handled by machinery constructed to handle tubes having the external outline aforementioned. This can in particular be the outline of the larger packing tubes currently in use.

Preferably at least the second portion of the adapter has an internal projection to prolong that of the packing tube.

The present invention also relates to the combination of a packing tube and an adapter or adapters according to the invention, and to a package consisting of DIL encapsulated components in a packing tube fitted with such an adapter or adapters.

The invention will now be described by way of example with reference to the accompanying drawings, wherein Figure 1 is a cross-section through a packing tube of the prior art and a DIL encapsulated integrated circuit; Figure 2 is a cross-section through a novel packing tube of smaller cross-section and a DIL encapsulated integrated circuit; Figure 3 is a perspective view of an adapter embodying the invention, and Figure 4 is a lengthwise vertical section through the adapter of Figure 3.

In Figure 1 there can be seen a section through a typical packing tube 1 as currently used, with a DIL encapsulated component 5 in position. The tube is extruded from clear plastics material. The tube is substantially trapezoidal in section, with a shorter side 15 parallel to a longer side 23 with inclined sides 21 therebetween. From the side 23 there extends inwardly a rectangular projection having two long sides 3 and a short side 13 parallel to the short side 15. The rectangular projection runs the length of the tube. For tubes currently used the dimensions P, Q, R and S are 8 mm, 13 mm, 7 mm and 15 mm. The DIL encapsulated components 5 are placed in the tube such that the undersides 8 rest on side 13 of the projection, with the leads or pins 7 of the DIL encapsulated components in the space between the sides 21, and the sides 3 of the projection.When the tube is filled, the DIL encapsulated components are retained by a pair of pins, one at each end of the tube, each pushed through a pair of holes punched through side 15 and side 13. The pins have a large flat head, and a frusto-conical portion at the tip, this portion at its greatest diameter having a diameter greater than that of the shank of the pin, and slightly greater than that of the holes in the tube, thus giving a snap action retention of the pin.

From Figure lit is clearthatthere is considerably more space provided for accommodating the DIL encapsulated components than they actually require especially with regard to the height 3 of the projection and the distance between side 13 and side 15, which space accommodates the bodies of the components.

A more suitable, smaller section tube is shown in section in Figure 2, which is to the same scale as Figure 1. In this tube 9, the height of the sides 11 of the projection, the breadth of sides 25 and 29 and the distance between side 17 and side 19 are reduced compared with the corresponding parts of the tube of Figure 1. Side 17 is also slightly wider than side 13 in Figure 1 to reduce the lateral movement of the DIL encapsulated component. The reduction of the distance between sides 17 and 19 reduces the amount of vertical movement which the component can undergo. The dimensions pl, Q1, R' and S1 are 8 mm, 10 mm, 5 mm and 11 mm respectively.

As previously mentioned the tubes currently in use are commonly manipulated by machines. So that these machines can handle smaller section tubes, such as those of Figure 2, without their requiring modification, the present invention provides adapters to fit over the ends of the smaller section tubes, giving an increased cross-section at the ends to conform with the size of section of packing tubes currently used, and enabling them to be handled by the same machinery.

An example of the adapter embodying the present invention is shown in perspective in Figure 3, and in section in Figure 4, where the end of the packing tube of Figure 2 is also shown, in phantom. The adapter is elongate and hollow, and is preferably made by injection moulding of plastics material.

As can be seen from Figure 4, a first portion of the adapter, i.e. from Ato C, sleeves over the end portion of a packing tube and a second portion, i.e.

from C to B, projects beyond the end of the tube. The adapter has walls of substantially uniform thickness and is of substantially trapezoidal internal and external cross-section for the whole of its length, the cross-sectional area increasing from the end A of the adapter to the end B. The adapter has an internal projection running the length of the adapter from A to B the projection being of substantially rectangular cross-section and providing a prolongation of the internal projection of the packing tube.

The packing tube enters the adapter at point A, and is able to sleeve into the adapter as far as point C, which represents the transition point between the first and second portions of the adaptor. Stops 27 are provided on surfaces 31 and 33 of the adapter to prevent entry of the packing tube beyond point C.

At its end B the adapter has the same external cross-section and dimensions as those of the packing tubes currently in use (i.e. the tube of Figure 1), with edge 3a of the adapter equal in length to the breadth of side 3 of the tube; edge 13a corresponding to the breadth of side 13; 15a to 15; 21a to 21 and 23a to 23. At the other end, A of the adapter, the internal dimensions are mostly the same as the external dimensions of the cross-section of the smaller section tube 9 of Figure 2, so that the end A closely surrounds the tube 9. The resilience of both the plastics adapter and the packing tube enables the adapter to grip the tube. The internal length of edge 19a of the adapter corresponds with the external breadth of side 19 of the tube; and there is a similar correspondence of edge 17a with side 17; edge 25a with side 25 and edge 29a with side 29.The length of edge 1 lea i.e. the perpendicular distance between surfaces 33 and 35 at the end A of the adapter is shorter than that of side 11 of the tube as the surface 22 is inclined relative to the surface 31 of the adapter, and to the sides 17, 19 and 29 of the tube when fitted into the adapter. The perpendicular distance between surfaces 31 and 33 does not become equal to the distance between surfaces 17 and 19 of the tube 9 until the point C. This inclination of surface 33 aids location of the tube onto the adapter by providing a "lead-in"surfaceforthe underside 17 of the projection of the tube. The inclination also provides a wedging action between underside 17 and the surface 33. Furthermore the inclination provides the correct edge length 3a at the larger section end B of the adapter, without surface 33 requiring to have a step in it.

In use, a packing tube as illustrated by Figure 2 is fitted with an adapter at each end before the tube is filled. The tube then effectively has, at its extremities, the same dimensions as the larger tubes currently in use, and the adapters provide a smooth lead-in to the interior of the tube.

The adaptors are also required during emptying of the tube, and they are retained in place while the filled tube is in transit, although it will be appreciated that it would be possible for the adapters to be removed before the filled tube is despatched, and fresh adapters fitted at the factory where the tube is to be emptied.

Claims (11)

1. An adapter for the ends of packing tubes for dual-in-line encapsulated components, said tubes being hollow, elongate and of uniform cross-section which includes an internal projection to be straddled by the components, the adapter being generally tubular and consisting of a first portion to be sleeved over one end of a packing tube, and a second portion to prnjectfrom the end thereof, at least part of said first portion having an internal cross-section of dimensions to closely surround at least part of said packing tube, and at least a region of said adapter having a cross-section whose external outline is substantially trapezoidal and of larger area than the cross-section of said packing tube, the adapter being provided internally with stops to abut the end of the packing tube and so limit the entry of the packing tube into the adapter.

2. An adapter according to claim 1 wherein at least the second portion has an internal projection to prolong that of the packing tube.

3. An adapter according to claim 1 or claim 2 wherein no part projects outside the said substan tially trapezoidal external outline.

4. An adapter according to any one of the preceding claims wherein the substantially trapezoidal external outline is provided at the free extremity of the said second portion.

5. An adapter according to any one of the preceding claims wherein the free extremity of the said first portion has an internal cross-section of dimensions to closely surround the trapezoidal cross-section of the packing tube.

6. An adapter according to claim 5 as appendent to claim 4 wherein for its whole length the adapter is of substantially trapezoidal cross-section both internally and externally with a substantially rectangular projection to be straddled by the components extending inwardly from the longer parallel side of the trapezium, the cross-sectional areas increasing progressively from the free extremity of the first portion to the free extremity of the second portion.

7. An adapter according to claim 6 wherein the stop surfaces project from the shorter parallel side of the trapezoidal cross-section and from the confronting surface of the said projection.

8. An adapter according to any one of the preceding claims injection moulded from plastics material.

9. An adapter substantially as herein described with reference to the accompanying drawings.

10. In combination, a hollow elongate packing tube of uniform cross-section which includes an internal projection to be straddled by dual-in-line encapsulated components, and an adapter according to any one of the preceding claims sleeved onto at least one end of the tube.

11. A package comprising a hollow elongate packing tube of uniform cross-section which includes an internal projection, a plurality of dual-inline encapsulated components placed end-to-end in the tube and straddling the said projection, and an adapter according to any one of the preceding claims sleeved on to at least one end of the tube.