GB2091682A - Article-containing barrels for treatment apparatus - Google Patents

Abstract

A barrel for containing articles to be treated in a treatment apparatus, which may be of the walking beam type, is provided with indexing means. The barrel (10) has a ratchet wheel (35) securing concentrically with its axis (12) and rotatable by a drive pawl (34) associated with a bush (32) mounted on the axis (12). The bush is rotated via a link (30, 31) from a bell crank lever having an upper arm (27) affording an actuating portion and a lower arm (28). The bell crank levers pivoted centrally at (26) to a support of the barrel, to which the lower arm (28) of the bell crank lever is resiliently attached. In use, reciprocal movement of the upper arm (27) of the bell crank lever indexes the barrel forwardly, reverse rotation being prevented by a stationary pawl (36) engageable with the ratchet wheel (35). <IMAGE>

Description

SPECIFICATION Barrel for treatment apparatus This invention relates to a barrel for a treatment apparatus for workpieces.

It has been devised particularly for use in a "walking beam" type of treatment apparatus in which a plurality of treatment stations are provided disposed side-by-side along the apparatus and transporter means are provided to transport workpieces from one treatment station to the next along the apparatus. Such treatment apparatus may be used for cleaning, pickling, plating and similar treatments applied to workpieces. Usually, each treatment station will comprise a tank of a liquid into which the workpieces are immersed for treatment but there may be treatment stations where articles are sprayed with a liquid or treated with a gas, for example warm air for drying purposes. The particular details of the process being carried out are not relevant to the present invention.

Many different types of workpiece may need to be treated. In some cases, workpieces are supported on jigs or in open-topped baskets, but the present invention is directed towards a fully enclosed barrel made of a perforated material to allow access of the treatment medium to the articles.

It is essential, when workpieces are enclosed in a barrel, to ensure that the treatment medium penetrates fully through the perforated barrel and flows freely around the workpieces. Treatment apparatus has been proposed in which each barrel is provided with an external toothed gear wheel which can engage a drive gear at each of the stations, the individual drive gears being driven by respective electric motors. The barrel is rotated by the motor so that the workpieces inside are tumbled through the treatment medium which percolates into the barrel.

However, this rotation arrangement is of limited applicability, since the axis of the barrel needs to be stationary so as to engage the drive gear. The barrel can only be rotated at the treatment station when it is in the treatment medium. Where cupshaped articles are being treated, or the barrel contains a large number of very small articles, quite large quantities of the treatment medium may be lifted out of the tank at the treatment station when the articles are removed from the treatment medium. It would be desirable to be able to rotate the barrel just above the surface of the treatment medium for drainage purposes but this has not been possible with the fixed drive motor and spur gear arrangement referred to.

British Patent No. 394,201 is directed towards a treatment apparatus of a type in which drums provided on frames are moved along a treatment tank by a walking beam arrangement and are rotated at the highest points of their travel by fixed abutments provided in the tank, engaging ratchet wheels secured to the drums. However, the drums are immersed in the tank throughout the process of transporting and rotating them.

Our co-pending Patent Application No.

2,043,01 2A, for which the present application is divided, is directed towards a walking beam type transporter in which rotation of the barrel can take place at any time when the barrel is carried by the walking beam, irrespective of whether it is in or above the treatment medium.

It is an object of the present invention to provide a barrel for containing articles to be treated in a treatment apparatus and having new or improved indexing means.

The barrel may be operated by a walking beam type treatment apparatus of the type described and claimed in our co-pending Patent Application No. 2,043,01 2A.

According to this invention there is provided a barrel for containing articles to be treated in a treatment apparatus, the barrel comprising support means, a barrel body rotatably mounted on said support means and indexing means including a lever linkage capable of indexing the barrel body rotationally relative to the support means.

The indexing mechanism may comprise a ratchet wheel rigidly secured to the barrel body and indexed relative to the support means in one direction of rotation of the lever linkage, and pawl means adapted to hold the ratchet wheel against rearward movement after each forward indexing movement of the ratchet wheel.

The ratchet wheel may be rotationally indexed by a drive pawl associated with a bush member mounted coaxially with the barrel.

A lever member may be pivotally mounted on the support means for rocking movement, a portion of the lever member spaced from its pivot being linked to the bush member by link means and the lever member also having an actuating portion spaced from its pivot, movement of the actuating portion being transmitted via the link means to rotate the bush member.

The lever member may be resiliently biased so as to resist rotation in the direction causing indexing movement of the ratchet wheel.

The lever member may be resiliently biased so as to resist rotation in the direction causing indexing movement of the ratchet wheel.

The lever member may be a bell crank lever.

The invention will now be described in more detail by way of example only, with reference to the accompanying drawings, in which: FIGURE 1 is a side elevation, partly broken away of a barrel shown to a small scale; FIGURE 2 is a detail side elevational view of a reciprocable barrel drive means suitable for indexing the barrel shown in Figure 1; FIGURE 3 is an axial sectional view of the barrel of Figure 1 in use in a walking beam type treatment apparatus; FIGURE 4 is a side elevational view of an operating means for the reciprocable barrel drive means of Figure 2; FIGURE 5 is a sectional view of the line 5-5 of Figure 4; FIGURE 6 is a perspective view of the treatment apparatus.

In the following description of the construction and functioning of the barrel embodying the invention, brief reference will be made to a walking beam type treatment apparatus, as described and illustrated in our co-pending Patent Application No. 2,043,01 2A from which the present application is divided, by way of example only.

Referring firstiy to Figure 1 of the drawings, a barrel is generally indicated at 10 and is of constant hexagonal cross-section, having one wall provided with a closure through which articles for treatment are inserted and from which they are withdrawn at the end of the treatment cycle. The barrel is mounted for rotation about an axis 12, the ends of which are journalled in a frame 13, shown partly broken away for clairty.

The frame comprises a pair of limbs 14 which receive the opposed ends of the axis. Each limb has, at its lower end, a rigid transverse foot 1 5.

The upper ends of the limbs are provided with means for resting on a flange of a main transporter beam of the walking beam type apparatus shown in the drawing, the support arrangements being seen more clearly in Figure 3 of the drawings and also being illustrated somewhat diagrammatically in Figure 2.

A flange 1 6 of the main transporter beam generally indicated at 17 7 supports a pair of pegs 18, each of which is welded to a respective angle bracket 1 9 which in turn is welded to the top of each limb 14. Two pegs are provided at opposed ends of the angle bracket at each end of the barrel and a pair of stops 20 are welded to the flange 1 6 of the main beam at each treatment station The barrel is therefore supported by four pegs 18, located by four stops 20, two at each of the barrel.

The walking beam type treatment apparatus with which the barrel may be used is of generally conventional design as shown in Figure 6 and comprises a row of treatment stations 9 disposed side-by-side, together with a main transporter beam 17 for up and down movement and also for longitudinal movement relative to the stations.

Each treatment station 9 is provided with suitable guides and also with a support bracket 21 which can support a load to be treated. The main transporter walking beam 1 7 picks up a load at a first loading station, raises it, moves longitudinally of the apparatus until the load is directly above the first treatment station, lowers the load until it reaches and is supported and by the support brackets 21 at the treatment station and then continues moving downwardly to release the load temporarily. The beam then moves longitudinally in the reverse direction so as to return toward the loading station.

It will be appreciated that repeated movement of the beam will tend to work the load along the apparatus to the discharge end, generally indicated at 7. A series of loads can therefore be treated simultaneously, each load occupying an adjacent treatment station.

The present invention is directed towards barrels for use with a treatment apparatus such as that shown in Figure 6 and is compatible with use of the treatment apparatus with workpieces supported on jigs or in baskets for example, as well as those supported in barrels according to the invention.

Rotation of the barrels is provided for by means of a reciprocating barrel dirve mechanism generally indicated at 22 in Figure 2 of the drawings, and extending along one side wall of the main transporter beam 1 7. The reciprocating barrell drive operates an indexing mechanism generally indicated at 23 on the side of the barrel so that the barrel can be indexed rotationally about the axis 12.

The indexing mechanism is operated by a lever linkage generally indicated at 24 which is mounted on a bracket 25 fixed to the limb 14 of the barrel frame. The lever linkage 24 comprises a bell crank lever pivotally mounted about an axis 26 on the bracket and comprising a first arm 27 and a second, perpendicular arm 28. The arm 28 is biased upwardly by means of a strong spring 29 which is housed within the hollow limb 14. The outer end of the second arm 28, remote from the pivotal axis 26, is attached by a link 30,31 to a bush 32 which also carries a lug 33.The lug has a pivoted pawl 34 which engages a ratchet 35 fixed with respect to the barrel 1 0. Also mounted on the barrel 10 is a support pawl 36 which acts in generally known manner to support the ratchet 35 against reverse movement when the pawl 34 is not in driving engagement with a tooth of the ratchet 35.

The way in which the ratchet device operates is that the upper end of the first arm, forming an actu'ating portion, is rocked from side to side relative to its pivotal axis 26, thereby causing the second arm 28 of the bell crank lever to operate the links 30 and 31 and hence to rotate the ratchet 35 via the pawl 34. When the ratchet has rotated by a certain fraction of its circumference, determined by the placing of the ratchet teeth, the support pawl slips over one of the teeth and prevents the ratchet from return movement when the swinging movement of the first arm 27 is reversed.

The first arm 27 the first arm is rocked by the reciprocable barrel drive 22 shown in Figure 2. For clarity in Figure 2, the first arm 27 is not shown but a roller 37 provided at the upper end of the first arm 27 is indicated.

The roller 37 is disposed between a pair of flanges 38, 39 when the reciprocable barrel drive is operating. The flange 38 and 39 are mounted on a plate 40 which is fixed on a rod 41 extending along the entire length of the apparatus.

The rod 41 is mounted on the main transporter beam 17 for reciprocation relative to the beam.

The beam is provided with a low friction cushion 42 disposed at the rear of the rod, together with pairs of freely rotatable low friction support bushes 43 which guide the rod 41 for smooth longitudinal movement relative to the main beam 1 7.

The rod 41 is reciprocated and moves the flanges 38 and 39 back and forth from right to left as shown in Figure 2 of the drawings. The roller 37 is therefore positively pushed back and forth from right to left, swinging the arm 27 of the bell crank lever between the limit positions shown in chain dotted lines in Figure 2.

The operating means for the reciprocating barrel drive rod 41 are described in more detail in our co-pending Patent Application No.

2,043,012A and detailed reference is therefore not necessary in the present application.

A pendulum link 47 shown in Figures 4 and 5 of the drawings is swung by a heavy duty piston and cylinder assembly, a component of the swinging movement being arranged to reciprocate the rod 41.

As long as the main transporter beam transports the barrel, the arm 27 can be rocked by movement of the rod 41 and hence the indexing mechanism can operate as desired. It is immaterial whether the barrel is submerged in a liquid at a treatment station 9 or whether it is raised whilst the barrel is being transported from raised slightly above the liquid. Indexing can even operate whilst the barrel is being transported from one station to another if this is desired. In particular, it will be noted that the barrel can be indexed while it is being dunked by raising and lowering the main transporter beam.

Claims (8)

1. A barrel for containing articles to be treated in a treatment apparatus, the barrel comprising support means, a barrel body rotatably mounted on said support means and indexing means including a lever linkage capable of indexing the barrel body rotationally relative to the support means.

2. A barrel according to Claim 1 wherein the indexing mechanism comprises a ratchet wheel rigidly secured to the barrel body and indexed to the support means in one direction of rotation of the lever linkage, and pawl means adapted to hold the ratchet wheel against rearward movement after each forward indexing movement of the ratchet wheel.

3. A barrel according to Claim 2 wherein the ratchet wheel is rotationally indexed by a drive pawl associated with a bush member mounted coaxially with the barrel.

4. A barrel according to Claim 3 wherein a lever member is pivotally mounted on the support means for rocking movement, a portion of the lever member spaced from its pivot being linked to the bush member by link means and the lever member also having an actuating portion spaced from its pivot, movement of the actuating portion being transmitted via the link means to rotate the bush member.

5. A barrel according to Claim 4 wherein the lever member is resiliently biased so as to resist rotation in the direction causing indexing movement of the ratchet wheel.

6. A barrel according to Claim 4 or Claim 5 wherein the leverl member is a bell crank lever.

7. A barrel for containing articles to be treated in a treatment apparatus, the barrel being substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

8. Any novel feature or novel combination of features disclosed herein and/or shown in the accompanying drawings.