US2648461A

US2648461A - Automatic means for the movement of comminuted materials

Info

Publication number: US2648461A
Application number: US18898A
Authority: US
Inventors: James R Stephenson
Original assignee: Individual
Current assignee: Individual
Priority date: 1948-04-05
Filing date: 1948-04-05
Publication date: 1953-08-11
Anticipated expiration: 1970-08-11

Description

1, 1953 J. R. STEPHENSON ,648 4-6 AUTOMATIC MEANS FOR THE MOVEMENT 0F 'COMMINUTED MATERIALS Filed April 5, 1948 2 Sheets-Sheet J.

Aug. 11, 1953 J. R. STEPHENSON AUTOMATIC MEANS FOR THE MOVEMENT OF COMMINUTED MATERIALS Filed April 5, 1948 2 Sheets-Sheet 2 FIG3 D2 vemfor: mes R. Gfep/l/QSO/JZ.

Patented Aug. 11, 1953 AUTOMATIC MEANS FOR THE MOVEMENT OF COMMINUTED MATERIALS James R. Stephenson, Winnipeg, Manitoba,

Canad Application April 5, 1948, Serial No. 18,898

4 Claims.

My invention relates to new and useful improvements in feeding mechanisms for furnace stokers, the principal object of the invention being to provide a device of the character herewithin described whereby an adequate supply of fuel is available at all times at the stoker feeding auger.

A further object of the invention is to provide a device of the character herewithin described which due to its construction will operate :over a substantial area of the fuel bin, thus reducing the necessity for supervision of the stoker and the manual handling of the fuel.

Another object of my invention is to provide a device of the character herewithin described which operates when there is a deficiency of fuel at the feeding auger and which ceases to operatejwhen this deficiency has been remedied.

A still further object of my invention is to provide a device of the character herewithin described whereby the possibility of the actuating switch becoming inoperative due to interference of the fuel is eliminated.

Another object of my invention is to provide a device of the character herewithin described which is designed for use in a bin or hopper having a horizontal floor, thereby resulting in the utilization of the entire fuel storage space.

A further object of my invention is to provide a device of the character herewithin described which incorporates a fire-proof switch in order to actuate a remote source of power, thus eliminating the danger of explosion taking place within the fuel bin.

Another object of my invention is to provide a device of the character herewithin described which is of sturdy construction and which is readily adaptable for use in the movement of other comminuted material such as crushed rock, grain, or the like.

With the foregoing objects in view, and such other objects and advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, my invention consists essentially in the arrangement and construction of parts all as hereinafter more particularly described, reference being had to the accompanying drawings, in which:

Figure 1 is a perspective reperesentation of my device installed for use in a fuel bin.

Figure 2 is an enlarged fragmentary view along the lines 22 of Figure l.

Figure 3 is an enlarged fragmentary perspective view of my switch assembly and discharge cavity.

In the drawings like characters of reference indicate corresponding parts in the different figures.

Since the inception of the self-feeding stoker system for furnaces considerable difficulty has been experienced in providing a device which is readily adaptable to comparatively large installations where it is not possible, for economic or structural reasons, to use the conventional sloping floor hopper. Conversion of relatively large capacity furnaces situated in confined locations has been delayed because of the difficulty in providing adequate space for the installation of special hoppers, and considerable difficulty has also been experienced in attempting to provide a device controlled by the main furnace stoker mechanism which will maintain a constant and adequate supply of fuel at the point of discharge without undue pulverization of the coal.

Many diverse systems have been designed in the past in an endeavour to overcome these disadvantages but the majority have failed due to the lack of an efficient switch mechanism specifically intended to be operated by the movement of comminuted material. Consequently I have invented the device hereinafter to be described in order to overcome the foregoing objection, and which incorporates a novel switch particularly suited for use with any comminuted material.

Proceeding now to describe my invention in detail it will be seen upon reference to the accompanying drawings to consist of the vertical drive shaft I mounted for rotation within the barrel 2 which in turn is supported by the pedestal bearing 3 attached to the superstructure 4 by the bolts 5 or similar means. In order to prevent the possibility of any gas or dust becoming ignited by electrical arcing the motive unit 6 is situated exteriorly of the fuel bin and power is transmitted by the belts l connectingthe pulleys 8 and 9 which of course are splined or keyed to their respective shafts. The lowermost end of the vertical shaft l enters the gear box l0 and actuates the sweeping auger il through the medium of conventional worm and pinion gearings. The gear box is rigidly attached to the aforementioned barrel 2 by means of flange l2 and becomes part of the sweeping assembly collectively designated I3 pivoting therewith as will hereinafter be explained.

It will be seen that the sweeping assembly is horizontally disposed, parallel with and adjacent to the floor of the bin and comprises the aforementioned sweeping auger li supported by the bearing I4 attached to the gear box It and by the bearing I5 which is carried by the end plate I6 of the elongated fender IT. The fender which in this embodiment is constructed from angle iron comprises the raking portion [8 which is substantially in contact with the floor of the bin, and the horizontally elongated substantially vertically disposed plate l9 which as well as acting as a stiffening web for the assembly also prevents undesirable displacement of fuel by the sweeping auger II as will hereinafter be described.

The diagonal stiffening rod is rigidly connected to the outboard end 2| of the fender and extends upwardly and inwardly to connect via the sleeve 2| with the aforementioned vertical barrel 2 substantially towards the uppermost end thereof. This bracing rod provides rigidity to the structure and maintains the sweeping assembly substantially in contact with the floor of the bin whilst allowing the complete assembly to move in a horizontal plane pivoting in the aforementioned pedestal bearings 3. Attached sub- 'stantially towards the outboard end of the aforementioned fender I8 is the rope or cable 22 extending over the conveniently located pulleys 23 to the adjustable weight 24 which serves the purpose of maintaining the sweeping assembly [3 in contact with the margin of the fuel mass at all times. It will be realized that the weight and pulley system may be replaced or assisted by hydraulic, pneumatic, or other mechanical means, but the arrangement illustrated is considered adequate for this embodiment.

The angulated finger 25 is rigidly attached on the outboard end of the sweeping auger II and rotates therewith in order to provide clearance for the end plate IS with the fuel mass, as it will be realized that the weight 24 may be insufficient to overcome the inertia of the sweeping assembly if the end plate is registering against a relatively large piece of fuel. The auger ll may be provided with either a left or righthanded flight, but it is desired that the lefthanded flight shown in this embodiment be utilized as it has been found advantageous to have the overside of the auger rotating towards the aforementioned elongated fender I! as this assists in the movement of the fuel towards the discharge cavity 26 with the minimum of pulverization. It will .be appreciated however that whether a left or right-handed flight is utilized the rotation of the auger should be such that the material is urged towards the discharge cavity and in the appended claims for the purpose of explication the auger flight has been defined as moving towards the point of discharge.

The rotation of the auger H is controlled by the switch operating movement collectively designated 2! which is rigidly attached to the gear box by the bracket 28 in a position superjacent to the discharge cavity 26 and in advance of the longitudinal axis of the auger. The movement comprises the horizontally disposed rod 29 mounted for rotation within the offstanding angulated bracket 30 and having a plurality of spaced and parallel flexible wire fingers 3| depending therefrom. The wire fingers are shown in this embodiment rigidly inserted within a head piece 3 l which is adjustably mounted upon the rod 39 by the clips 32, thus forming what I designate as a material interceptable component 32. Rigidly attached to the inboard end of the aforementioned rod 29 and extending transversely therefrom is the switch actuating actuating bar 33.

bar 33 which connects via the linkage 34 to the switch 35. The switch makes and breaks the circuit controlling the operation of the aforementioned motive unit 6 and is shown in the on" position in Figures 1 and 2 of the accompanying drawings. From the foregoing it will be appreciated that the material intercepting component 32 will normally maintain the switch in this position assisted by the weight 36 attached to the outboard end of the aforementioned switch A relatively small extension spring ma be substituted for the weight spanning the outboard end of the actuatin bar and the lower portion of the gear box I0. It is desirable that this switch should be of fireproof construction in order to eliminate the possibility of explosion taking place within the bin or hopper.

Having described my invention in detail, its method of operation will now be presented.

When the fuel is loaded into the bin or' hopper the sweep arm assembly [3 should be moved in the direction of the arrow3l sufficient to ensure that all the fuel is deposited in advance of the unit. If the quantity of fuel supplied is too great to permit the angle of repose of the fuel to reach the floor, the fuel will feed by gravity to the discharge cavity 26 until the fuel adjacent the cavity is evacuated, thereupon the device will operate as hereinafter described, although without transverse movement of the sweeping assembly. The assembly is kept in contact with the margin of the mass of fuel by the weight 24, and gradually sweeps across the floor as the fuel is consumed. When a deficiency of fuel occurs in the discharge reservoir 26 the resilient wire'fingers'3l will take up a vertical position assisted by the offset weight 36 thus operating the switch which completes the circuit through the medium 'of electrical conduit 38 thereby starting the rotor 6. This causes rota tion of the auger I l in a clockwise direction when viewed from the outboard'end l of the'asse-m'bly as hereinbefore described, thereby causing fuel to move towards the discharge reservoir 26. The fuel is maintained within the auger channel by means of the relatively high vertical fender l1 and when the reservoir becomes full, the fuel commences to build up between the inboard end of the auger H and the aforementioned resilient wire fingers 3|. This excess fuel causes the'displacement of the Wire fingers away from the auger as clearly shown in Figure 3 of the accom panying drawings, and-it is desired that the resiliency of the fingers should be such that the inertia of the weight 36 will not be overcome until several of the fingers are distorted. It will be appreciated that if the displacement of a single finger only was relied upon to overcome this inertia, then premature actuation of the switch unit might result due to the interference of a relatively large piece of fuel. When sufficient fuel has been delivered to the discharge reservoir to cause the displacement of several of the wire fingers, the inertia of the weight 36 is overcome, thus allowing partial rotation of the rod 29 in the direction of the arrow 39 thereby actuating the switch 35 via the aforementioned linkage 34v and breaking the circuit of the motive unit 6. The main stoker feed auger 40, which is situatedsu b stantially towards the bottom of the discharge reservoir 26, conveys the fuel therefrom to the furnace (not illustrated), the quantity being regulated thermostatically in the conventionalmajn ner. When the level of fuel in the discharge'reservoir commences to fall, the material intercept ing component returns to its normally vertical position assisted by the weight 36, thus closing the circuit and starting the motive unit 6. The weight 24 ensures continuous contact of the sweeping assembly with the margin of the fuel mass, thereby assuring the complete evacuation of the fuel from the bin without the need for supervision or manual handling of the fuel.

Since various modifications can be made in my invention as hereinabove described, and many apparently widely different embodiments of same made within the spirit and scope of the accompanying claims without departing from such spirit and scope, it is intended that all matter contained in the accompanyin specification shall be interpreted as illustrative only and not in a limiting sense.

What I claim as my invention is:

1. In the evacuation of comminuted materials from bins or hoppers, means for urging the comminuted mass to the point of discharge comprising a sweeping assembly including a horizontally disposed sweep-arm assembly movable in a horizontal plane substantially parallel to and in proximity to the bin or hopper floor, said sweeping assembly being pivoted for said movement substantially above the point of discharge, a source of power for efiecting such movement, said assembly embodying an elongated conveyor, an elongated fender in proximate parallel and trailing relation thereto, said fender including a horizontally elongated, substantially vertically disposed plate, means for urging said sweep arm assembly against the margin of said mass, a switch for initiating actuation of said conveyor, and a switch actuator adjacent said point of discharge consisting of a rotatable rod, a material interceptable component secured to said rod and projecting downwardly therefrom with the distal end of said component slightly spaced from and in advance of said elongated conveyor, and a switch throwing element extending between said rod and said switch and actuable by said rod upon movement of said component by comminuted material.

2. In the evacuation of comminuted materials from bins or hoppers, means for urging the comminuted mass to the point of discharge comprising a sweeping assembly including a horizontally disposed sweep-arm assembly movable substantially parallel to and in proximity to the bin or hopper floor, said sweeping assembly being pivoted for-said movement substantially above the point of discharge, a source of power for efiecting such movement, said assembly embodying an elongated conveyor, an elongated fender in proximate parallel and trailing relation thereto, said fender including a horizontally elongated, substantially vertically disposed plate, means for urging said sweep arm assembly against the margin of said mass, a switch for initiating actuation of said conveyor, and a switch actuator adjacent said point of discharge, consisting of a rotatable rod, a material interceptable component in the form of a set of flexible fingers secured to and projecting downwardly from said rod with the distal ends of said fingers parallel with. and slightly spaced from and in advance of said elont5 gated conveyor, and a switch throwing element extending between said rod and said switch and actuable by said rod upon movement of said fingers by comminuted material.

3. In the evacuation of comminuted materials from bins or hoppers, means for urging the comminuted mass to the point of discharge comprising a sweeping assembly including a horizontally disposed sweep-arm assembly movable substantially parallel to and in proximity to the bin or hopper floor, said sweeping assembly being pivoted for said movement substantially above the point of discharge, a source of power for eflecting such movement, said assembly embodying an elongated conveyor, an elongated fender in proximate parallel and trailing relation thereto, said fender including a horizontally elongated, substantially vertically disposed plate, means for urging said sweep arm assembly against the margin of said mass, a switch for initiating actuation of said conveyor, and a switch actuator adjacent said point of discharge movable out of switch operating position by the movement of said comminuted material, and a radially extending rotatable finger on the end of said elongated conveyor opposite to the point of discharge.

4. In the evacuation of comminuted materials from bins or hoppers, means for urging the comminuted mass to the point of discharge comprising a sweeping assembly including a horizontally disposed sweep-arm assembly movable substantially parallel to and in proximity to the bin or hopper floor, said sweeping assembly being pivoted for said movement substantially above the point of discharge, a source of power for effecting such movement, said assembly embodying an elongated conveyor, an elongated fender in proximate parallel and trailing relation thereto, said fender including a horizontally elongated, substantially vertically disposed plate, means for urging said sweep arm assembly against the margin of said mass, a switch for initiating actuation of said conveyor, and a switch actuator adjacent said point of discharge, consisting of a rotatable rod, a material interceptable component in the form of a set of flexible fingers secured to and projecting downwardly therefrom with the distal ends of said fingers parallel with and slightly spaced from and in advance of said elongated conveyor, and a switch throwing element extending between said rod and said switch and actuable by said rod upon movement of said component by comminuted material, and a radially extending rotatable finger on the end of said elongated conveyor opposite to the point of discharge.

JAMES R. STEPHENSON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,479,990 Keys Jan. 8, 1924 1,482,524 Robinson Feb. 5, 1924 1,570,085 Saxe Jan. 19, 1926 2,232,545 Lum Feb. 18, 1941 2,445,056 Cordis July 13, 1948