GB2052009A - Vibratory apparatus - Google Patents

Abstract

A vibratory conveyor comprises a trough 11 supported by pivoted legs 14 from a base 17, with isolation springs 18 mounted between the base and the trough. An exciter member 22 vibrated by an eccentric mass vibrator 28, is suspended from the trough by pivoted arms 23, force transmitting springs 24 being provided. The legs 14, arms 23 and springs 18, 24 are so oriented that vibrations of the trough 11 have a substantially greater horizontal than vertical movement whereby the vertical acceleration of material carried by the conveyor is less than the acceleration of gravity and therefore the material conveyed does not physically leave the surface of the conveyor. The result is a smooth flow of material from one end of the trough to the other. <IMAGE>

Description

SPECIFICATION Vibratory apparatus Vibratory conveyors have been known and used for many years. In the usual type of vibratory conveyor, the material-carrying trough is vibrated at an angle to the horizontal normally of the order of 45 degrees. The material conveyed is, in effect, bounced along the trough from one end to the other to effect the conveying action. Thus, for most of the travel the material is airborne, striking the material-carrying surface only long enough to be relaunched into the air in the direction of the discharge end of the conveyor. The vibratory action has been used not only for conveying articles from one end of the- trough to the other, other functions can be achieved, such as for example, the removal of sand from castings because of the jarring or impact nature of the vibratory conveying action.Thus, the trough may be provided with a foraminous lower surface through which sand may pass as it is jarred loose from the castings. An example of such an apparatus is to be found in the U.S. Musschoot patent No. 3,335,861.

Because of the bouncing nature of the conveying actions, it has heretofore been difficult, if not impossible, for a worker standing alongside the trough to actually pelYorm any work on the articles being conveyed. Thus, in a foundry operation, it is customary for a worker to knock the sprue from a casting with a hammer, but in order to do so the casting must be at rest or at least be maintained in a position where such a blow can be delivered with a reasonable degree of accuracy. Heretofore, this could not be accomplished while the casting was passing along a vibratory conveyor.

The present invention provides a vibratory conveyor where the conveying action is relatively smooth and thus the articles being conveyed appear to flow from one end of the conveyor to the other rather than to bounce therealong. The smooth flow is accomplished by arranging the supports carrying the conveying trough in a manner to predetermine the vibratory direction of the trough so as to permit the trough to move primariiy horizontally with only a small but necessary vertical component to facilitate conveying action. Thus, the motion of the trough is at an angle of close to 10 degrees to the horizontal, some 80 degrees from the vertical. The arrangement is such that the vibratory forces applied to the trough in a vertical direction accelerate the material in the trough upwardly at a lesser degree than the acceleration due to gravity.

Thus, the articles never leave the trough but are always supported thereby, although because there is a vertical component in the vibration, the articles are substantially unweighted during the vibratory cycle and thus will appear to flow from one end of the conveyor to the other. As the motion of the articles being conveyed is smooth and without bounce, it is easy for a workman standing beside the trough to deliver a blow to the sprue of a casting and free the casting therefrom.

In one embodiment of the invention, there is thus provided a vibratory conveyor comprising an elongated material-carrying member, a base, a plurality of legs supporting the said member, each leg having one end pivotally secured to the material-carrying member and the other end pivotally secured to the base, each leg extending from base to trough at an angle of from 700 to 800 to the horizontal, a plurality of isolation springs, each isolation spring having one end connected to the material-carrying member and the other end connected to the base, each isolation spring extending upwardly from base to material-carrying member at an angle of from 100 to 200 to the horizontal, an exciter member, a plurality of arms suspending the exciter from the material-carrying member, each of said arms having one end pivotally secured to the materialcarrying member and the other end pivotally secured to the exciter member, a plurality of force transmitting springs, each of said force transmitting springs having one end secured to the material-carrying member and the other end secured to the exciter member, each force transmitting spring extending upwardly from the exciter member to the material-carrying member at an angle of from 100 to 200 with the horizontal, and means for vibrating the exciter member.

A further feature of the invention is the unique mounting and support for the material-carrying trough and exciter relative to the base, the particular arrangement being one in which the base for the most part is supporting only the weight of the apparatus, i.e., the weight of the trough and exciter, and the dynamic forces generated by the vibrations, of the trough and exciter are isolated from the base so that substantially no dynamic forces are transmitted to the base. This is a particularly important feature in very long conveyors where hertofore substantial dynamic forces were transmitted to the base and thus required a much heavier construction.

In another embodiment of the invention, there is provided a vibratory conveyor comprising an elongated material-carrying member, a base, a plurality of parallel legs supporting the member each leg having one end pivotally secured to the material-carrying member and the other end pivotally secured to the base, a plurality of isolation coil springs, each isolation spring having one end connected to the material-carrying member and the other end connected to the base, each isolation spring extending upwardly from base to material-carrying member and having a spring effect exerted 900 to the longitudinal extent of the legs, an exciter member, a plurality of parallel arms suspending the exciter from the material-carrying member, each of said arms having one end pivotally secured to the materialcarrying member and the other end pivotally secured to the exciter member, said arms being parallel to the legs, a plurality of force transmitting springs, each of said force transmitting coil springs having one end secured to the material-carrying member and the other end secured to the exciter member, the axis of each force transmitting spring extending upwardly from the exciter member to the material-carrying member at an angle of 900 to the longitudinal extent of the arms and parallel to the axis of the isolation springs, and means for vibrating the exciter member.

in order that the invention may be more fully understood, one embodiment thereof will now be described with reference to the accompanying drawing in which: Figure 1 is a side elevational view of a conveyor embodying the features of the invention; and Figure 2 is an enlarged sectional view of a portion of the apparatus shown in Figure 1.

Referring now to the drawings, there is shown a vibratory conveyor 10 having a material-carrying member in the form of a trough 11. The trough is elongated from an entrance chute 1 2 at the lefthand end thereof (as seen in Fig. 1), which chute receives material from a conveyor 13 stationarily mounted adjacent the chute.

The trough 11 is carried by a plurality of parallel legs 14, each pivotally secured at its upper end to brackets 1 5 mounted on the underside of the trough 11 and at their lower end to a bracket 1 6 mounted upon a base 1 7 fixed to the building or other structure carrying the apparatus. The legs in the particular embodiment shown are arranged at an angle of from 70 to 80 degrees to the horizontal, with an angle of aprroximately 72-1/2 degrees being preferred where the smooth flow of the material being conveyed is of primary concern.

A plurality of isolation springs 18 extend between and are secured to brackets 19 fixed to the base 17 and brackets 20 fixed to the underside of the trough 11. The isolation springs 18 are shown as coil springs whose axes extend at right angles to the legs 14.

Suspended beneath the trough 11 is an exciter member 22 carried by a plurality of parallel arms 23 each pivoted at one end to the trough and at the other end to the exciter member. A plurality of force transmitting springs 24 extend upwardly from the exciter to the trough, with each of said springs bearing at its lower end against U-shaped channels 25, extending transversely beneath the trough and secured thereto and a second plurality of channel members 26 extending transversely between the sides 27 of the exciter member and being secured thereto. The force transmitting springs 24 have axes which are parallel to the axes of the isolation springs 1 8 and the arms 23 are parallel to the legs 14.

The exciter member 22 is elongated in a direction parallel to the elongation of the trough 11 with the exciter including parallel side members 27 between which the transverse channels extend. The weight of the exciter is approximately 50 per cent of the weight of the trough and as during vibration it moves in a direction opposite to the direction of the trough, it serves not only as an exciter but also as a conterbalance member to diminsh the amount of vibrational force imparted to the structure in which the conveyor is housed.

An electric motor 28 is carried on the exciter member 22 with the electric motor having a shaft extending horizontally and transverse to the direction of elongation of the trough. The shafts of the motor are connected to eccentric weights and the arrangement is preferably that shown in Musschoot U.S. patent No. 3,358.815, so that the vibratory force imparted by the motor to the exciter may be varied from substantially zero to maximum. Thus, the amplitude of the movement of the exciter and hence the trough may be varied to produce the desired flow characteristics of the material being conveyed by the trough.

Because of the direction of vibration of the trough 11 in the particular embodiment shown is substantially parallel to the axes of the isolation springs 18, the motion is primarily horizontal and thus very little vertical vibrational force must be carried by the base 1 7. Because the vertical vibrational force is minimized, the vibratory conveyor of the present invention may be mounted on a relatively light foundation and thus may be actually mounted and used on upper floors of a building rather than being confined to the lowermost floor where it can be supported on relatively missive foundations.

Furthermore, becasue of the arrangement of the legs 14 and arms 23 relative to the isolation springs 1 8, substantially none of the dynamic force of the vibrating masses is transmitted to the base 17. The absence of such dymanic force on the base permits it to be designed simply to carry the weight of the apparatus without necessarily possessing the strength to absorb and accommodate dynamic vibrational forces normally imparted to such bases in the normal form of construction of vibratory conveyors.

Claims (8)

1. A vibratory conveyor comprising an elongated material-carrying member, a base, a plurality of legs supporting the said member, each leg having one end pivotally secured to the materiai-carrying member and the other end pivotally secured to the base, each leg extending from base to trough at an angle of from 700 to 800 to the horizontal, a plurality of isolation springs, each isolation spring having one end connected to the material-carrying member and the other end connected to the base, each isolation spring extending upwardly from base to material-carrying member at an angle of from 100 to 200 to the horizontal, an exciter member, a plurality of arms suspending the exciter from the material-carrying member, each of said arms having one end pivotally secured to the materialcarrying member and the other end pivotally secured to the exciter member, a plurality of force transmitting springs, each of said force transmitting springs having one end secured to the material-carrying member and the other end secured to the exciter member, each force transmitting spring extending upwardly from the exciter member to the material-carrying member at an angle of from 100 to 20 with the horizontal, and means for vibrating the exciter member.

2. A conveyor according to claim 1 wherein the exciter member is elongated in the direction of the elongation of the material-carrying member and has a mass equal to approximately one-half of the mass of the material-carrying member.

3. A conveyor according to claim 1 or 2, wherein the means for vibrating the exciter member comprises an electric motor carried by the exciter member, a horizontal shaft extending transversely of the direction of elongation of the trough and rotated by the mOtor, an eccentric weight at each end of the shaft, and means for varying the eccentricity of the weight to impart variable vibratory forces to the exciter member.

4. A conveyor according to claim 1 or 2, wherein the said means for vibrating the exciter member is arrayed to produce vertical acceleration on material carried by the material-carrying member less than the acceleration of gravity.

5. A conveyor according to claim 1, 2, 3 or 4, wherein each leg extends from base to materialcarrying member at an angle of approximately 1 7+0 to the horizontal; each isolation spring extends upwardly from base to material-carrying member at an angle of approximately 17- to the horizontal, and each force transmitting spring extends upwardly from the exciter member to the material-carrying member at an angle of approximately 1 7+0 to the horizontal.

6. A vibratory conveyor comprising an enlongated material-carrying member, a base, a plurality of parallel legs supporting the member each leg having one end pivotally secured to the material-carrying member and the other end pivotally secured to the base, a plurality of isolation coil springs, each isolation spring having one end connected to the material-carrying member and the other end connected to the base, each isolation spring extending upwardly from base to material-carrying member and having a spring effect exerted 900 to the longitudinal extent of the legs, and exciter member, a plurality of parallel arms suspending the exciter from the material-carrying member, each of said arms having one end pivotally secured to the materialcarrying member and the other end pivotally secured to the exciter member, said arms being parallel to the legs, a plurality of force transmitting springs, each of said force transmitting coil springs having one end secured to the material-carrying member and the other end secured to the exciter member, the axis of each force transmitting spring extending upwardly from the exciter member to the material-carrying member at an angle of 900 to the longitudinal extent of the arms and parallel to the axis of the isolation springs, and means for vibrating the exciter member.

7. A vibratory conveyor according to claim 6, wherein the isolation springs are coil springs and the exciter member is elongated in the direction of the elongation of the material-carrying member and has a mass equal to approximately one-half of the mass of the material-carrying member.

8. A vibratory conveyor substantially as herein described with reference to Figures 1 and 2 of the accompanying drawings.