GB1583788A

GB1583788A - Vibrators

Info

Publication number: GB1583788A
Application number: GB23091/79A
Authority: GB
Original assignee: FMC Corp
Current assignee: FMC Corp
Priority date: 1976-09-01
Filing date: 1977-08-23
Publication date: 1981-02-04
Also published as: FR2374095A1; FR2374096A1; GB1583787A; AU2689777A; ZA774056B; AU512571B2; MX144791A; BR7705732A; DE2738794B2; ES462057A1; NL7709070A; FR2374094A1; DE2738794A1; JPS5332582A; CA1077303A; DE2738794C3; JPS5628803B2

Description

PATENT SPECIFICATION

( 21) Application No 23091/79 ( 62) Divided out of No 1583787 ( 31) Convention Application No 719634 ( 22) Filed 23 Aug 1977 ( 32) Filed 1 Sep 1976 in ( 33) United States of America (US) ( 44) Complete Specification Published 4 Feb 1981 ( 51) INT CL 3 B 06 B 1/16 K ( 52) Index at Acceptance F 25 SL ( 72) Inventor: William Risinger Brown ( 54) IMPROVEMENTS IN OR RELATING TO VIBRATORS ( 71) We, F Mc CORPORATION, a Corporation organised and existing under the laws of the State of Delaware, United States of America, of 200 E Randolph Drive, Chicago, State of Illinois, United States of America, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the follow-

ing statement:-

The present invention relates to vibrators, and more particularly, to vibrators utilizing eccentric weights to produce the desired vibrations.

Vibrators are used to induce vibrations in various types of industrial equipment for diverse purposes such as feeding material, screening material, or dislodging material In some applications, such as in a two mass vibrating system used to feed material at a predetermined rate, the magnitude of the stroke of the vibrator is important.

According to the present invention, there is provided a vibrator comprising two eccentrically weighted elements rotatable about a common axis, means operable to drive one of said elements, a clutch connected between said elements to connect said elements in any desired phase relation so that both elements will rotate when said one element is driven and said clutch is engaged, and a brake operable to retard the rotation of said other element when said clutch is disengaged and said brake is applied to change in infinite variation the phase relation between said elements.

Further according to the present invention, there is provided a vibrator comprising a first shaft, a first eccentric weight mounted on said first shaft, said first weight and first shaft defining a first eccentrically weighted element, a hollow shaft mounted coaxially on the first shaft, a second eccentric weight mounted on said hollow shaft, said second eccentric weight and hollow shaft defining a second eccentrically weighted element, a clutch connected between said first and second eccentrically weighted elements to selectively connect said elements in any desired phase relation for rotation in unison, means operable to rotate one of said eccentrically weighted elements, and a brake 50 operable to retard the other of said eccentrically weighted elements relative to the said one element whereby to alter in infinite variation the relative angular position of said elements.

Still further according to the present inven 55 tion, there is provided a vibrator comprising two concentric shafts each having an eccentric weight secured thereon, a drive motor connected to one of said shafts for driving said one shaft, an electrically operated clutch having a 60 rotor and an armature secured on respective ones of said shafts for selective connection and disengagement of said shafts in any desired phase relation, a brake comprising a brake armature secured to said other of said shafts to 65 retard said other shaft while said one shaft is driven by said motor to thereby change in infinite variation the angular relationship between said eccentric weights from a predetermined angular relationship, and a spring con 70 nected between said shafts to store energy when said shafts are shifted from said predetermined angular relationship, and to release energy when said clutch is released to disengage said shafts and to move said eccentric 75 weights toward said predetermined angular relationship.

Still further according to the present invention, there is provided a vibrator comprising two eccentrically weighted rotatable ele 80 ments, means operable to drive one of said elements, a clutch interposed between said elements and engageable to connect said elements in any desired phase relation so that both elements will rotate in unison when said 85 one element is driven and said clutch is engaged, and a brake operable to retard the rotation of said other element when said clutch is disengaged and said brake is applied to change in infinite variation the phase rela 90 tion between said elements.

An embodiment of the invention will now be described by way of example only, with reference to the accompanying diagrammatic drawings, in which: 95 Figure 1 is a view in perspective of an electro-mechanical vibrating feeder incorporating a vibrator in accordance with the present in( 11) 1583788 1 583 788 vention; Figure 2 is a side elevation, in section, of a vibrator in accordance with the present invention; S Figure 3 is a section taken on line 3-3 of Figure 2; and Figure 4 is an exploded view, in perspective, of the eccentric weights of the vibrator of Figure 2.

There is shown in Figure 1 a vibrator 10 constructed in accordance with the present invention The vibrator 10 is shown, for illustrative purposes, as the driving force of a vibratory feeder 12 which is designed to receive material at an input end 12 a and discharge material at a discharge end 12 b The vibrator of the present invention can be used to drive other machines, such as vibratory screens or, in fact, any equipment which it is desired to vibrate.

It will be understood by those skilled in the art that the feeder 12 includes a trough 14 which is suspended by springs 16 from an overhead support The feeder has a drive housing 15 which is rigidly connected to trough 14, and the housing 15 has spaced walls 15 a, 15 b The vibrator 10 is mounted by means of springs 18 between the walls 15 a, 15 b to form with the trough a two mass, spring coupled, electromechanical vibratory feeder.

As shown in Figures 2, 3 and 4, the vibrator comprises a housing 100 having bearings 102 and 104 mounted in openings in sidewalls 106, 108 Bearing 104 receives a shaft 110 for rotation on an axis B on which both bearings 102, 104 lie A hollow shaft 112 is mounted on shaft 110, and is received in bearing 102 for rotation in axis B. A first eccentric weight 114, which is secured to shaft 110, has a centre of gravity spaced from the axis B, which is the longitudinal axis of rotation of shaft 110 The weight 114, and the shaft 110 on which it is eccentrically mounted, constitute a first eccentric element 116 A second weight 118 consists of two side members 118 a, 118 b, which straddle the weight 114, and an arcuate perimeter member 118 c outboard of weight 114 to connect the side members 118 a 118 b One side member 118 a of weight 118 is keyed on hollow shaft 112 for rotation therewith, and the other side member 118 b is rotatably mounted on shaft The weight 118 has a centre of gravity spaced from axis B, and is therefore eccentric with respect to hollow shaft 112 The weight 118 and the hollow shaft 112 constitute a second eccentric element 120.

An electric clutch 122 (which may be similar to Model SFC-650 of the Warner Electric Brake & Clutch Company, Beloit, Wisconsin) is connected between shaft 110 and hollow shaft 112 The clutch has an electromagnetic stationary unit 122 a connected to housing 100.

A rotor 122 b is received on hollow shaft 112 for rotation therewith, and an armature 122 c is received on shaft 110 for rotation therewith.

When switch 124 is closed to connect the terminals of unit 122 a across the source of energy 126, the armature engages the rotor for rotation in unison of shaft 110 and hollow shaft 112 70 An electric brake 128 (which may be similar to Model PB-500 of the Warner Electric Brake & Clutch Company, Beloit, Wisconsin) has a stationary magnetic unit 128 a which is connected to housing 100 An armature 128 b is moun 75 ted on hollow shaft 112 for rotation therewith.

When switch 130 is closed (and switch 124 simultaneously opened) the magnetic member 128 a is connected across energy source 126 to engage the armature 128 b with stationary unit 80 128 a and retard the rotation of hollow shaft 112 At the same time, the clutch is deenergised to release the hollow shaft 112 from the shaft 110.

A flat coil spring 132 has one end connected 85 to shaft 110 (of first eccentric element 116) and the opposite end to weight 118 (of second eccentric element 120) Thus, the spring exerts a bias between the first eccentric element 116 and the second eccentric element 120 tending 90 to urge these members toward positions where the eccentric elements are in opposed relationship for minimum eccentricity.

An electric motor 134 is mounted on housing 100 A pulley 136 mounted on the motor 95 drive shaft (not shown) is connected by belt 138 to a pulley 140 on shaft 110.

During normal operation of the vibrator, motor 134 is driving shaft 110, and switch 124 is closed (switch 130 open) to energise clutch 100 122 Thus, clutch 122 is engaged to connect shaft 110 and hollow shaft 112 for rotation in unison At this time the eccentric weights are in relative position for minimum eccentricity, with abutment surface 114 a of weight 114 en 105 gaged with stop bar 141 In this relative position, the stroke of the driven unit 142 (which may, for example, be a conveyor or a vibrating screen), is minimum If it is desired to increase the stroke, the switch 124 is momentarily 110 opened (disconnecting hollow shaft 112 from shaft 110), and the switch 130 momentarily closed, to energise the brake The energisation of the brake retards the rotation of hollow shaft 112 while shaft 110 continues to rotate 115 at its normal speed As sleeve 112 is retarded, the relative position of the weights changes, increasing the eccentricity of the combined weights 114 and 118 At the same time, the spring 132 winds up, storing potential energy 120 The switch 124 is intermittently opened and closed while simultaneously the switch 130 is intermittently closed and opened until the relative position of the weights produces the desired stroke, at which time the switch 24 is 125 held closed and the switch 130 is held open.

Thus, the shaft 110 and hollow shaft 112 are again connected together for rotation in unison.

When, eventually, a smaller stroke is again desired, the switch 144 is intermittently opened 130 1 583 788 and closed to momentarily deenergise the clutch (without energising the brake) to permit the spring 132 to return the weights to the desired angular relationship, at which time switch 144 is again closed Since switch 124 is already closed (and switch 130 open), the clutch 122 again connects shaft 110 to hollow shaft 112.

The mounting of the eccentric weights in accordance with the manner described enables infinite adjustment of the eccentric weights to be accomplished while the vibrator is in an operative mode.

Claims

WHAT WE CLAIM IS:-

1 A vibrator comprising two eccentrically weighted elements rotatable about a common axis, means operable to drive one of said elements, a clutch connected between said elements to connect said elements in any desired phase relation so that both elements will rotate when said one element is driven and said clutch is engaged, and a brake operable to retard the rotation of said other element when said clutch is disengaged and said brake is applied to change in infinite variation the phase relation between said elements.

2 A vibrator comprising a first shaft, a first eccentric weight mounted on said first shaft, said first weight and first shaft defining a first eccentrically weighted element, a hollow shaft mounted coaxially on the first shaft, a second eccentric weight mounted on said hollow shaft, said second eccentric weight and hollow shaft defining a second eccentrically weighted element, a clutch connected between said first and second eccentrically weighted elements to selectively connect said elements in any desired phase relation for rotation in unison, means operable to rotate one of said eccentrically weighted elements, and a brake operable to retard the other of said eccentrically weighted elements relative to the said one element whereby to alter in infinite variation the relative angular position of said elements.

3 A vibrator according to claim 2, further comprising a spring connected between said first and second elements to bias said elements toward a predetermined angular relationship.

4 A vibrator comprising two concentric shafts each having an eccentric weight secured thereon, a drive motor connected to one of said shafts for driving said one shaft, an electrically operated clutch having a rotor and an armature secured on respective ones of said shafts for selective connection and disengagement of said 55 shafts in any desired phase relation, a brake comprising a brake armature secured to said other of said shafts to retard said other shaft while said one shaft is driven by said motor to thereby change in infinite variation the angular 60 relationship between said eccentric weights from a predetermined angular relationship, and a spring connected between said shafts to store energy when said shafts are shifted from said predetermined angular relationship, and to re 65 lease energy when said clutch is released to disengage said shafts and to move said eccentric weights toward said predetermined angular relationship.

A vibrator according to claim 4, wherein 70 said one shaft is received inside said other shaft, said clutch armature is connected to said one shaft, said clutch rotor in connected to said other shaft and an electromagnetic stator is mounted adjacent said rotor to draw, when 75 energised, said clutch armature into engagement with said rotor to connect said shafts for rotation in unison.

6 A vibrator according to claim 4 or claim 5, wherein said brake further comprises a sta 80 tionary electromagnetic unit operable to draw, when energised, said brake armature into engagement therewith to retard said other shaft.

7 A vibrator according to any one of claims 4 to 6, wherein in said predetermined angular 85 relationship, the eccentric weights are in mutually opposed positions.

8 A vibrator comprising two eccentrically weighted rotatable elements, means operable to drive one of said elements, a clutch interposed 90 between said elements and engageable to connect said elements in any desired phase relation so that both elements will rotate in unison when said one element is driven and said clutch is engaged, and a brake operable to retard the 95 rotation of said other element when said clutch is disengaged and said brake is applied to change in infinite variation the phase relation between said elements.

9 A vibrator substantially as hereinbefore 100 described with reference to the accompanying drawings.

MATHISEN, MACARA & CO, Chartered Patent Agents, Lyon House, Lyon Road, Harrow, Middlesex, H Al 2 ET.

Agents for the Applicants.

Printed for Her Majesty's Stationery Office by MULTIPLEX medway ltd, Maidstone, Kent, ME 14 1 JS 1981 Published at the Patent Office, 25 Southampton Buildings, London WC 2 l AY, from which copies may be obtained.