GB2058286A - Vibratory shaker - Google Patents

Abstract

A vibratory shaker for separating scallops from their shells comprises a platform 1 held above a base 4 by supports 5,5'. The platform 1 has a mesh screen floor 3, and each of the supports 5,5' includes a rotatable shaft 8,8', and a pair of legs 10,10' attached to the platform. Each pair of legs 10,10' is associated with a respective one of the shafts 8,8'. Each leg 10,10' is attached to a respective end of the corresponding shaft 8,8' by engagement with a cylindrical boss eccentrically positioned on said shaft end so that rotation of the shafts causes oscillatory reciprocation of the legs, and vibration of the platform 1. Each shaft 8,8' is provided with a counter-weight dynamically balancing that shaft to compensate for the eccentric positioning of the respective bosses. Means 12, 13 and 14 are provided for rotating the two shafts 8,8' in unison. <IMAGE>

Description

SPECIFICATION Vibratory shaker This invention relates to a vibratory shaker for separating the sheels from scallops during scallop processing.

A scallop processing line usually has five stages, namely a washer which removes dirt from the scallop shells, an opener for automatically opening the scallop shells, a separator for separating the scallop meat and attached viscera from the shells, a brine floatation separator for removing shell fragments and sand from the scallop meat and viscera, and an eviscerator for removing the viscera from the scallop meat. The present invention relates to a particular form of separator for separating scallop meat and attached viscera from scallop shells, namely a vibratory shaker. Known vibratory shakers have a mesh screen which is vibrated to agitate the open scallops and separate the scallop meat and viscera from the shells. The mesh of the screen is sized to permit the meat and viscera to fall therethrough, but to prevent the fall of the shells.

Scallop lines of this type are usually installed on shore. This means that the scallops have to be brought to the shore for processing. As the greater part (by both weight and volume) of scallops is taken up by their shells, it would obviously be desirable to process the scallops on board the boats where they are caught, as this would entail fewer journeys to and from the catchment areas.

Unfortunately, up to now, it has not been possible to install a scallop processing line on the type of boat normally used for catching scallops. This is because such boats are usually quite small, and the intense vibration, which is necessary to separate the scallop meat and viscera from the shells, would be transmitted through the base of the vibratory shaker (which of necessity must be fixed firmly to the deck of the boat), and would tend to loosen the rivets or welds holding the deck plates together so weakening the deck strength.

Thus, the mesh screen of one known type of vibratory shaker is held in a platform supported on vertical springs and located on horizontal posts. A rotating eccentric weight is fixed to the platform to provide the vibration. The springs cushion the shock in the vertical plane but do not prevent horizontal shock being transferred to the base.

Alternatively, the platform is supported on flexible leaves and driven via a push rod by an eccentric revolving shaft. Here again, there is no prevention of the shocks caused by the rotation of the out-ofbalance weight of the eccentric shaft being transferred to the base of the machine.

The present invention provides a vibratory shaker for separating scallops from their shells, the vibratory shaker comprising a platform held above a base by support means, the platform having a floor constituted by a mesh screen, and the support means being constituted by a pair of rotatable shafts mounted on the base and by two pairs of legs attached to the platform, each pair of legs being associated with a respective one of the shafts, wherein each leg is attached to a respective end of the corresponding shaft by engagement with a cylindrical boss eccentrically positioned on said shaft end, whereby rotation of the shafts causes oscillatory reciprocation of the legs and vibration of the platform, each shaft being provided with a counter-weight dynamically balancing that shaft to compensate for the eccentric positioning of the respective bosses, and therein means are provided for rotating the two shafts in unison.

By ensuring that the two shafts are driven in unison, and by dynamically balancing the shafts by means of the counter weights, the shock transmitted to the base by the vibrating platform is kept to a minimum in both horizontal and vertical planes. Consequently, this vibratory shaker can be used on board small boats without any danger of loosening of the rivets which hold the plates of the boat together.

Preferably, each leg is attached to the platform with the inter-position of a shock absorber. The shock absorbers prevent any forces arising from uneven loading of the platform being transmitted through the legs to the base.

Advantageously, the shafts are driven, via toothed timing belts, by means of a motor mounted on the base.

Conveniently, the mesh size of the screen is so chosen that scallops can fall therethrough, but their shells cannot.

Means may also be provided for collecting the scallops which fall through the mesh screen.

Advantageously, the two shafts are positioned at opposite ends of the base, and the collecting means is positioned therebetween.

A vibratory shaker constructed in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side elevation of the vibratory shaker; Figure 2 is a plan view of the vibratory shaker with part of the platform removed; Figure 3 is a cross-section, on an enlarged scale, taken on the line A-A of Figure 1; and Figure 4 is a cross-section, on an enlarged scale, taken on the line B-B of Figure 1.

Referring to the drawings, Figures 1 and 2 show a vibratory shaker having a platform 1 provided with side walls 2 and a wire mesh floor 3. The mesh size of the floor 3 is such that scallops can fall through, but their shells cannot.

The platform 1 is mounted above a base 4 by supports 5 and 5' positioned at the ends of the base. A funnel-shaped tray 6 is fastened to the under side of the platform to guide the de-shelled scallops into a container 7 positioned on the base between the two supports 5 and 5'.

The supports 5 and 5' are each constituted by a shaft 8, 8' which is rotatably mounted in a pair of bearing blocks 9, 9' attached to the base 4, and a pair of upstanding legs 10, 10' which are connected to the side walls of the platform 1 via respective shock absorbers 11. The right-hand (as viewed in Figures 1 and 2) shaft 8 is driven, via a pair of V-belts 12, by means of a motor 13 mounted on the base 4. The left-hand shaft 8' is driven by the right-hand shaft 8 via a toothed timing belt 14. The belts 12 and 14 co-operate with pulleys 1 2a and 1 4a on the right-hand shaft 8, with a pulley 1 2b on the shaft of the motor 13, and with a pulley 1 4b on the left-hand shaft 8'.

Thus, the two shafts 8 and 8' are rotatably driven in unison.

Figure 4 shows the connection between one of the legs 10' and the shaft 8'. Here, the end of the shaft 8' is provided with a bolted-on, eccentrically-positioned cylindrical boss 1 5 which engages a bushing 16 fastened to the lower end of the leg 10' by means of a ball bearing 17. The bearing 17 is held in place within the bushing 1 6 by means of an end plate 18 bolted onto the bushing. The other leg 10' of the shaft 8' is connected thereto in an identical manner.

Similarly, the two legs 10 are connected to bosses provided at the two ends of the shaft 8. In order to balance the shafts 8 and 8' dynamically, each is provided with a bolted-on counterweight 19 to counter balance the weight of the eccentrically positioned bosses.

In use, opened-up scallops are fed to the vibratory shaker from a known type of shell opener. The opened-up shells are placed on the wire mesh floor 3 of the platform 1, and the motor 13 is turned on. This rotates the two shafts 8 and 8' in unison, which in turn cause the cylindrical bosses (such as 1 5) to orbit around the axes of the shafts. This orbital movement of the bosses 15 causes the legs 10 and 10' to execute an oscillatory and reciprocatory movement, which in turn vibrates the platform 1. The vibration of the platform 5 causes the scallops to separate from their shells, and to fall through the apertures in the mesh screen floor 3. The scallops are then directed into the container 7 by the funnel-shaped tray 6.

Because the two shafts 8 and 8' are driven in unison, and because each of the shafts is dynamically balanced, shock transmitted to the base 4 from the vibrating platform 1 is kept to a minimum in both horizontal and vertical planes.

The shock absorbers 11 prevent additional shocks being transmitted from the platform 1 to the base 4 when the platform is unevenly loaded. Thus, this form of vibratory shaker is suitable for use on board the fairly small boats which are traditionally used for catching scallops.

Claims (6)

1. A vibratory shaker for separating scallops from their shells, the vibratory shaker comprising a platform held above a base by support means, the platform having a mesh screen floor, and the support means including a pair of rotatable shafts mounted on the base and two pairs of legs attached to the platform, each pair of legs being associated with a respective one of the shafts, wherein each leg is attached to a respective end of the corresponding shaft by engagement with a cylindrical boss eccentrically positioned on said shaft end, whereby rotation of the shafts causes oscillatory reciprocation of the legs and vibration of the platform, each shaft being provided with a counter-weight dynamically balancing that shaft to compensate for the eccentric positioning of the respective bosses, and wherein means are provided for rotating the two shafts in unison.

2. A vibratory shaker as claimed in claim 1, wherein each leg is attached to the platform with the inter-position of a shock absorber.

3. A vibratory shaker as claimed in claim 1 or 2, wherein the shafts are driven, via a pair of V-belts, by means of a motor mounted on the base.

4. A vibratory shaker as claimed in any one of claims 1 to 3, wherein the mesh size of the screen is so chosen that scallops can fall therethrough, but their shells cannot.

5. A vibratory shaker as claimed in any one of claims 1 to 4, wherein collecting means are provided for collecting the scallops which fall through the mesh screen.

6. A vibratory shaker as claimed in Claim 5, wherein the two shafts are positioned at opposite ends of the base, and the collecting means is positioned between the two shafts.

.7. A vibratory shaker substantially as hereinbefore described with reference to, and as illustrated by, the accompanying drawings.