GB2024362A

GB2024362A - Apparatus for cleaning cores from castings

Info

Publication number: GB2024362A
Application number: GB7827907A
Authority: GB
Original assignee: WORSWICK A
Current assignee: WORSWICK A
Priority date: 1978-06-26
Filing date: 1978-06-26
Publication date: 1980-01-09
Also published as: GB2024362B

Abstract

Castings to be cleaned are loaded into a structure 1, rotatable in housing 2. The castings are gripped between grippers 12 and 13. As the structure 1 is e.g. index rotated, each casting passes a high pressure water jot emitted by a nozzle 21 which washes the casting 11. Each casting is gripped and washed in its own chamber 9. A flushing station may follow the cleaning jet. <IMAGE>

Description

SPECIFICATION Apparatus for cleaning cores from castings This invention relates to apparatus for cleaning sand or ceramic cores from ferrous or non-ferrous castings.

According to the invention, there is provided apparatus Tor cleaning cores from castings, comprising a rotatable structure divided into a plurality of separate chambers, a gripping device in each chamber for holding a casting, a drive for rotating the structure, and a high pressure water jet arranged outside the periphery of the structure.

The drive may conveniently rotate the structure in a stepwise manner so that at the end of each step, one of the chambers is positioned opposite the water jet.

The gripping devices are preferably operated by compressed air, and may grip castings automatically when the castings are pushed into the devices.

The water jet can be arranged to be swivelable so that the jet can be directed to different parts of the casting.

The rotatable structure is preferably formed like a revolving door, i.e. rotatable about a vertical axis, and divided into sector-shaped chambers by vertical partitions which intersect on the axis of rotation.

The apparatus may include a filtration unit arranged below the rotatable structure. Grids may be positioned between the clamps and the filtration unit to permit loosened core material and water to enter the unit, but to prevent larger objects from entering.

The invention will now be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a section through a first embodiment of a casting cleaning apparatus according to the present invention; Figure 2 is a plan view of the apparatus of Figure 1; Figure 3 is a schematic section through a second embodiment; and Figure 4 is a plan view of the apparatus of Figure 3.

The apparatus shown in Figure 1 comprises a rotatable structure 1 rotatable within a housing 2 positioned on top of a filtration unit 3. The structure 1 is rotatable about a vertical axis 4 by a motor 5. In the example shown, this motor is an eiectric motor which drives a friction disc 6 which is in contact with the inner surface 7 of the structure 1.

As can be seen in Figure 2, the rotatable structure 1 is constructed like a revolving door. It has four radial partitions 8, which form the boundaries of four chambers 9. A clamp loins arranged in each chamber 9. These clamps 10 are operated by compressed air and serve to clamp the castings which are being cleaned. On the lefthand side in FigUre 1, a clamp is shown open at the loading position. On the right-hand side of Figure 1, a clamp is shown gripping a casting 11.

To cause a clamp 10 to close, an operator introduces a casting to be clamped between the jaws 12 and 1 3. The casting is pushed back against the vertical strut 14, and this causes the strut 14 to pivot about axis 1 5. The linkage shown then causes disc 1 6 to be lowered, whereupon it actuates a switch 17 which initiates flow of compressed air to a cylinder 1 8 which drives strut 1 9 downwards to cause the upper jaw 12 to approach the lower jaw 13.Once clamping has been effected in this way, the clamp 10 returns to the vertical position shown under the influence of a spring 20, and the off centre force exerted by cylinder 1 8. When the clamp unit reaches the position at which the casting is to be released, a stationary cam 26 operates a switch 27 which admits air to the lower part of the cylinder 18 causing the strut 1 9 to rise and release the casting. The strut 19 is pivoted at its upper and lower ends to allow the clamp to swing backwards as described.

The particular embodiment of the apparatus shown in the drawings is relatively simple, in that it only has four chambers. Any number of chambers could of course be provided, depending on the number of operations which are to be carried out on the castings.

Considering the plan view shown in Figure 2, castings are loaded at the left-hand side of the Figure, and the rotatable structure 1 rotates in an anti-clockwise direction. After 1800 of rotation, a loaded casting is brought to a position in front of a high pressure water jet 21 directed at the casting itself. This jet is pivotably mounted and is controlled by a piston/cylinder unit 22, so that it can move relative to the casting. This jet 21 will direct water at a pressure of, for example, 3 to 8,000 p.s.i. at the casting.The water may carry a fine abrasive material. This high pressure water jet loosens and removes the casting core, which may be sand or ceramic material, and which is then washed down into the filtration unit 3. After washing, the structure 1 is turned through a further 900, to being the casting into an ejection position.

It would be possible to have the jet 21 arranged 900 beyond the loading position, and to have a casting washing station opposite the loading position, where the jet is shown in the drawings.

In this case, the jet would be used to break down and loosen the core, and the washing station would then wash away any loose sand remaining.

Grids 23 are arranged underneath the clamps 10. The washing water and loose sand pass through these grids into the filtration unit, but any parts of the casting which are inadvertently brokerl off do not pass through the grids and are directed to the side of the structure 1.

A seal 24 is provided between the rotatable structure 1 and the housing 2.

Instead of having a stepping drive via the motor 5, the structure 1 could be rotated continuously for certain applications, with the speed of rotation being geared to the length of tine necessary for carrying out operations at various points on the periphery of the structure.

When an indexing or stepping drive is used, the dwell time at each stationary point is dependant on the time required for carrying out the various operations.

An electrical control panel 25 is provided for controlling the operation of the apparatus.

Figures 3 and 4 show an embodiment which is adapted to facilitate the loading and unloading of heavy castings into the apparatus. In Figure 4, it will be seen that a segment of a top cover 40 has been cut away so that heavy castings 41 can be lowered into the apparatus from above by a crane.

The castings are lowered onto a cradle 42. Once they have been washed, the castings can be removed by a similar route. A water jet 43 is shown on the left-hand side of Figures 3 and 4.

In addition, a trough 44 is provided extending around a part of the apparatus where washing is to take place. Any debris dislodged from the castings will be collected in this trough 44, and a scraper blade 45 connected to the rotatable structure travels in this trough 44 and directs debris along the trough to a conveyor contained in a tangential section 46 which removes the debris.

Water can be removed as before and cleaned for re-use.

Claims

1. Apparatus for cleaning cores from castings, comprising a rotatable structure divided into a plurality of separate chambers, a gripping device in each chamber for holding a casting, a drive for rotating the structure, and a nozzle arranged outside the periphery of the structure for directing a high pressure water jet against a casting held in a gripping device.

2. Apparatus as claimed in claim 1, wherein the drive is adapted to rotate the structure in a stepwise manner, so that at the end of each step one of the chambers is positioned opposite the nozzle.

3. Apparatus as claimed in claim 1 or claim 2, wherein the gripping devices are operated by compressed air.

4. Apparatus as claimed in any preceding claim, wherein the gripping devices grip castings automatically when the castings are pushed into the devices.

5. Apparatus as claimed in any preceding claim, wherein the nozzle can be arranged to be swivellable so that it can direct a water jet to different parts of the casting.

6. Apparatus as claimed in any preceding claim, wherein the rotatable structure is divided into sector-shaped chambers by vertical partitions which intersect on a vertical axis, and is arranged to be rotatable about a vertical axis.

7. Apparatus as claimed in any preceding claim, including a filtration unit arranged below the rotatable structure.

8. Apparatus as claimed in claim 7, wherein grids are positioned between the clamps and the filtration unit to permit loosened core material and water to enter the unit, but to prevent larger objects from entering.

9. Apparatus for cleaning cores from castings, substantially as herein described with reference to Figures 1 and 2 or Figures 3 and 4 of the accompanying drawings.

New claims or amendments to claims filed on 9th October 1979.

Superseded claims 1 New or amended claims:

1. Apparatus for cleaning cores from castings, comprising a housing, a rotatable structure within the housing divided by partitions into a plurality of separate chambers, the partitions being adapted to seal against the inside of the housing to effect a seal between adjacent chambers, a gripping device in each chamber for holding a casting, a drive for rotating the structure, and a nozzle arranged outside the periphery of the structure for directing a high pressure water jet against a casting held in a gripping device.