GB2299289A - Apparatus for clinching an elongate strip to a flange - Google Patents

Abstract

Apparatus for clinching an elongate strip to a flange comprises a body 1 with a hammer element 5 which oscillates about a pivot axis 6 to drive a striker plate 38 towards a rotating anvil 32. The anvil is at one end of a shaft 3 which locates in bearings 21, 22 and positioned on the shaft is a cam 4. Hammer element 5 has a roller bearing 7 serving as a cam follower. The cam follower is biased, by means of a spring 31, to engage with cam means 4. The biassing pressure is adjustable by means of adjusting screw 29. In operation, as the shaft rotates the anvil rotates to drive the device along the work piece and the striker is driven towards and away from the anvil to provide an oscillating clinching force.

Description

APPARATUS FOR CLINCHING AN ELONGATE STRIP TO A FLANGE This invention relates to an apparatus for clinching an elongate strip to a flange. In particular, but not exclusively, the present invention relates to apparatus for the fitting and securing of an elongate strip provided with a channel to a flange which can be a single or double, simple or shaped flange, as found in a motor vehicle. The elongate strips which are to be applied by the apparatus to the flange include window glass channels, door seals, boot seals, waist seals, bonnet seals and trim finishes.

Many elongate strips are known which have a channel-shaped component comprising two opposing side walls and, extending between the two side walls, a base. Depending on the intended purpose of the elongate strip, sealing components or decorative components can be provided on the outer surface of the elongate strip. To provide extra securing qualities of the elongate strip in relation to the flange, the opposing side walls and base which define the channel can incorporate a reinforcing core in a known manner.

Also, for the purposes of enhancing the resistance to removal of the elongate strip from the flange, the opposing side walls can be provided with limbs or other projections which project into the channel, the projections preferably, but not necessarily, being inclined towards the base of the channel.

Generally the elongate strips are dimensioned so as to take account of the thickness of the flange to which the strip is to be secured, taking into account factors such as the distance between the opposing walls of the strip and the magnitude of any projections extending into the channel from those walls. Usually some reasonable degree of force is required in order to force an elongate strip onto a flange, and such force can cause damage to the elongate strip if not properly aligned with the flange.

The idea has therefore now been conceived of providing an elongate strip which initially can be put onto a flange without any significant force as a result of the opposing side walls being slightly splayed apart and then, thereafter, clinching the elongate strip onto the flange.

According to the present invention, there is provided an apparatus for clinching an elongate strip to a flange, the apparatus comprising: a rotatable anvil intended in use to be rotated at a constant speed of rotation; a hammer element having a striking face and capable of oscillation about a pivot axis such that the striking face can approach and retreat from the anvil; and cam means capable of being actuated or powered by rotation of the anvil and of causing the hammer element to oscillate about the pivot axis.

Conveniently, but not necessarily, the cam means can be fixedly mounted on the anvil so that the cam rotates with the anvil, with each nose of the cam contacting the hammer element or a cam follower mounted on the hammer element.

Alternatively, the anvil can, upon rotation, be capable of driving a gearing arrangement which in turn can actuate the cam which then acts on the hammer element or on a cam follower mounted on the hammer element.

The apparatus preferably includes biasing means which tends to cause the hammer element to pivot about the pivot axis in such a direction as to cause the striking face to retreat from the anvil, with action of the cam overriding the biasing means.

Conveniently, but not necessarily, the biasing means can be a compression spring, and preferably there is provision for adjusting the strength of action of the compression spring.

Preferably the rotatable anvil is carried by one or more than one bearing to allow smooth rotation of the anvil relative to a body component of the apparatus. The hammer element can be arranged within the same body component and mounted for pivotal movement in relation to the body component about the pivotal axis.

A region of the rotatable anvil which is, in practice, to abut the exterior of one opposing wall of the elongate strip can be smooth or may be provided with a tractive coating.

The body component, mentioned above, may have hollow regions for accommodating the hammer element and the anvil, and may be provided with a cover through which a portion of the anvil projects, to allow powered means to rotate the anvil. A lower region of the body component can be formed as a skate which can be allowed to rest on a part of the elongate strip corresponding to the exterior of the base between the opposing side walls, to assist in the smooth movement of the apparatus relative to the elongate strip.

For a better understanding of the present invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is a vertical section along a major axis through one embodiment of apparatus in accordance with the present invention; Figure 2 is a view from above of the apparatus of Figure 1, but with the cover removed so as to expose certain components within the body; Figure 3 is a view corresponding to that of Figure 2 but with the cover secured in place on the body; Figure 4 is an elevation of the apparatus of Figure 1, looking towards the left hand end of the apparatus shown in Figure 1; and Figure 5 is a horizontal section taken along the line V-V in Figure 4.

In the drawings, the reference numerals 1 to 8 indicate generally important main components of the illustrated apparatus. Thus there is shown a body component 1 which has a generally rectangular horizontal cross-section and various hollow zones (described in more detail hereafter), and is provided with a cover 2. Rotatably mounted within the body 1 is an anvil 3 on which is fixedly mounted on a cam 4.

Also mounted within the body 1 is a hammer element 5 capable of oscillating movement about a pivot 6 mounted in the body 1. The hammer element 5 carries a freely rotatable roller bearing 7 which serves as a cam follower intended to remain in contact with the cam 4.

Biasing means 8 tends to cause the hammer element 5 to be disposed such that the roller bearing 7 carried by the hammer element 5 remains in contact with the cam 4.

Still discussing the apparatus in general terms, it can be seen that the arrangement is such that rotation of the anvil 3 relative to the body 1 and cover 2 causes corresponding rotation of the cam 4.

The biasing means 8, which acts on the hammer element 5 between the roller bearing 7 carried by the hammer element 5 and the pivot 6 causes the roller bearing 7 to remain in contact with the cam 4, the arrangement being such that when a nose on the cam 4 bears increasingly on the roller bearing 7 the hammer element 5 is caused to pivot about the pivot 6 in an anticlockwise manner (as shown in Figure 1) such that the lower end region of the hammer element 5 approaches the lower end region of the anvil 3, whereby the desired clinching may be effected on an elongate strip positioned between the lower end region of the anvil 3 and the lower end region of the hammer element 5.

Considering the apparatus now in more detail, the body 1 has a first vertical axis 11 centrally provided about which, in an upper region of the body 1, is a large circular recess 12. Spaced some way from the first vertical axis 11 is a second vertical axis 13 centred on which is a smaller circular recess 14 also provided in an upper region of the body 1. Extending from the smaller circular recess 14 towards the large circular recess 12 and of the same width as the diameter of the smaller circular recess 14 is a rectilinear recess 15 which serves to join the large and smaller circular recesses 12, 14.

Also provided in the body 1, as best shown in Figure 2, are two screw-location holes 16, spaced either side of the rectilinear recess 15.

Also provided in the body 1 is a hole 17, most clearly shown in Figure 4, for locating the pivot pin 6, in a horizontal plane lying below the large and smaller circular recesses 12, 14.

Extending downwardly (in Figure 1) from the large circular recess 12 is a bore 18 for accommodating the anvil 3, the bore 18 being circular and lying on the first vertical axis 11. An upper recess 19 and a lower recess 20 are provided at upper and lower end regions of the bore 18 for accommodating, respectively, an upper bearing 21 and lower bearing 22 for the anvil 3.

Extending downwardly from the smaller circular recess 14 and lying on the second vertical axis 13 is a vertical first bore 23 capable of fully accommodating the hammer element 5 when the axis of the latter is vertical.

Also provided in the body 1 is a second bore 24 for accommodating the hammer element 5 when inclined to the vertical at its maximum inclination. The first and second bores 23 and 24 cross at the pivot point 6.

Areas between the first and second bores 23 and 24 are reamed, such as indicated by the line identified by the reference numeral 25 in Figure 2, so as to allow the hammer element 5 to pivot or rock about the pivot 6 between the vertical disposition in which its axis is aligned with that of the first bore 23 and an inclined disposition in which its axis is aligned with that of the second bore 24.

For the purpose of locating the biasing means 8, the body 1 is provided with a stepped bore 26, more information on the biasing means being provided hereafter.

Considering now the cover 2, this is provided with two screw holes 27 which allow the heads of two countersunk screws to be accommodated and for the screw portions to pass therethrough for location within the screw holes 16 in the body 1 to locate the lid 2 on the body 1. The cover 2 is also provided with a bore 28 to allow the anvil 3 to extend upwardly beyond the body 1, through the cover 2 and upwardly beyond the latter, so as to leave an exposed region to which power may be applied, for example by a pulley (not shown) to cause the anvil 3 to rotate at the desired rotational speed.

Reverting to the biasing means 8, located in the stepped bore 26 in the body 1 is a screw cap 29 having an external screwthread capable of cooperating with the internal screwthread in the larger step of the stepped bore 26, the screw cap 29 being rotatable by the action of a screwdriver in the exposed screw slot 30. In a state of compression between the screw cap 29 and a region of the hammer element 5 intermediate the pivot 6 and the roller bearing 7 is a compression spring 31 which serves to urge the upper part of the hammer element 5 towards the upper part of the anvil 3 and maintain the roller bearing 7 in contact with the cam 4.

The lowermost region of the rotatable anvil 3 projects below the body 1 and is optionally provided with a tractive coating 32 on its surface so as to ensure a good grip with an elongate element being clinched, and so as to assist in the rectilinear advance of such a strip during the continuous clinching exercise.

The cam 4 which is provided with three noses 4A, 4B and 4C (shown in Figure 2) is mounted for rotation with the anvil 3 with the aid of a cam fixing pin 33 which passes through the cam 4 and anvil 3, this pin 33 also being shown in Figure 2.

As indicated previously, the roller bearing 7 is mounted for free rotation on the hammer element 5 and is prevented from upward and downward movement along the hammer element 5 by upper and lower circlips 35 and 36, respectively.

Over most of its length the hammer element has a circular cross-section but it may be provided with a slight recess for the purpose of locating that end of the compression spring 31 which is remote from the screw cap 29.

At its lower end region the hammer element 5 is provided with a chamfered region 37 to which is secured by, for instance, tack welding a striking plate 38. It is this striking plate 38 which, during the clinching operation, abuts the external surface of one wall of an elongate strip, with the external surface of the opposing wall being trapped by the lower end region, which might be provided with the tractive surface 32, of the rotating anvil 3.

As most clearly shown in Figure 4, the lower region of the body 1 is tapered and, at its lowermost end region, is smoothly rounded so that it can move smoothly along the outer surface of the base of an elongate strip, the base being the region between the two opposing side walls of the elongate strip.

In the embodiment illustrated in Figure 1 the hammer element 5 is vertically disposed and lies on the second vertical axis 13, for the reason that the nose 4A of the cam 4 is pressing the roller bearing 7 as far as possible to the left (in Figure 1), but it can be appreciated that as the cam 4 rotates and the nose 4A recedes, the hammer element 5 can pivot about the pivot 6 clockwise (in Figure 1) so that its axis moves towards the axis of the second bore 24, with the consequent withdrawal of the striking plate 38 away from the tractive surface 32 of the anvil 3. The removal of the hammer element 5 and its striking plate 38 in readiness for the next clinching step allows the elongate strip to be advanced under the action of the anvil 3.

in the embodiment illustrated in the drawing, the cam 4 has three noses but it would be possible for it to have a different number, such as four.

Where the cam 4 is directly carried by the anvil 3, then the number of times in which the striking plate 38 moves towards the anvil 3 per complete revolution of the anvil 3 is dependent on the number of noses provided on the cam 4. If, however, there were some gearing between the rotating anvil 3 and the cam, it is possible to alter the rate of striking.

In the embodiment of apparatus illustrated in the drawings it is possible for the apparatus to deliver in continuum one hammer blow per centimetre of elongate strip although, as mentioned above, suitable gearing can permit variations.

The apparatus of the present invention can be dimensioned suitably to suit the components to be clinched; and with a speed of rotation of 600 to 700 r.p.m. for the motor which rotates the anvil the apparatus can advance relative to the elongate strip at, typically, 20 metres/minute.

Apparatus of the type illustrated in the drawings may be hand-held or rail mounted, and can be employed for simple or multi-head automatic/robotic use.

Claims (10)

1. An apparatus for clinching an elongate strip to a flange, the apparatus comprising: a rotatable anvil intended in use to be rotated at a constant speed of rotation; a hammer element having a striking face and capable of oscillation about a pivot axis such that the striking face can approach and retreat from the anvil; and cam means capable of being actuated or powered by rotation of the anvil and of causing the hammer element to oscillate about the pivot axis.

2. An apparatus according to claim 1, wherein the cam means is fixedly mounted on the anvil so that the cam rotates with the anvil, with the or each nose of the cam contacting the hammer element or a cam follower mounted on the hammer element.

3. An apparatus according to claim 1, wherein the anvil is capable, upon rotation, of driving a gearing arrangement which in turn can actuate the cam means which then acts on the hammer element or on a cam follower mounted on the hammer element.

4. An apparatus according to claim 1, 2 or 3, which also includes biasing means which tends to cause the hammer element to pivot about the pivot axis in such a direction as to cause the striking face to retreat from the anvil, with action of the cam means overriding the biasing means.

5. An apparatus according to claim 4, wherein the biasing means is a compression spring, and wherein there is provision for adjusting the strength of action of che compression spring.

6. An apparatus according to any preceding claim, which includes a body component, wherein the rotatable anvil is carried by one or more than one bearing to allow smooth rotation of the anvil relative to the body component; and wherein the hammer element is arranged within the same body component and mounted for pivotal movement in relation to the body component about the pivotal axis.

7. An apparatus according to claim 6, wherein the body component has hollow regions for accommodating the hammer element and the anvil, and is provided with a cover through which a portion of the anvil projects, to allow powered means to rotate the anvil.

8. An apparatus according to claim 6 or 7, wherein a lower region of the body component is formed as a skate which can be allowed to rest on a part of the elongate strip correspondiilg to the exterior of che base between the opposing side walls, to assist in the smooth movement of the apparatus relative to the elongate strip.

9. An apparatus according to any preceding claim, wherein a region of the rotatable anvil which is, in practice, to abut the exterior of one opposing wall of the elongate strip is smooth or is provided with a tractive coating.

10. An apparatus substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.