US1548834A - Ash-discharge amd clinjkeb-gbindeb structure - Google Patents

Ash-discharge amd clinjkeb-gbindeb structure Download PDF

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US1548834A
US1548834A US1548834DA US1548834A US 1548834 A US1548834 A US 1548834A US 1548834D A US1548834D A US 1548834DA US 1548834 A US1548834 A US 1548834A
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aprons
ram
refuse
discharge
apron
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B02CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02CCRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C17/00Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/16Mills in which a fixed container houses stirring means tumbling the charge
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B02CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
    • B02CCRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
    • B02C17/00Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls
    • B02C17/16Mills in which a fixed container houses stirring means tumbling the charge
    • B02C17/168Mills in which a fixed container houses stirring means tumbling the charge with a basket media milling device arranged in or on the container, involving therein a circulatory flow of the material to be milled

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  • nonnnr a roansMAN, or Moons
  • PENNSYLVANIA AssIsNon r'o wnsrrnenousn ELECTRIC AND MANUFACTURING COMPANY, a CORPQTION or rnNNsYLvANra.
  • ASH-DISC 1 RGE AND CLINKER-GJRINDER STRUCTU.
  • '. is'a side view, partially in section and partially in elevation, of a mechanical stoker of the underfeed type provided-with discharge mechanism constructed in accordance with my invention.
  • Figure 2 is a fragmentary view, in eleva tion, of a portion of the discharge mechanism, being taken on the plane I][H in Figure 1; and I Figure 3 is a detail view, partially in section and partially in elevation, of a modification of the apparatus shown in Figure 1.
  • aprons 16 and 17 depending from the lower edge of the active combustion grate
  • a similar apron 18 depending from the lower edge of the wall 14.
  • the combustion space for the stoker 10 The aprons 17 and 18 are deeply notched 'at their lower edges, as shown at 19 in Figures 1 and '2, and a ram 20 is mounted for transverse movement beneath the aprons 17 and 18.
  • the ram 20 comprises a main body portion, preferably formedhollow for the circulation of a suitable .cooling medium therethrough and having an upstanding fuel-agitating member 21 and two rows of crushing teeth 22, 22 at the sides thereof. These teeth are in alinement with the respective notches of the aprons 17 and 18, all for a purpose to be hereinafter pointed out.
  • the ram 20 is mounted on two sets" of vertically disposed levers '2323, these levers being pivotally mounted at 24--24.
  • the arrangement is such that as the levers 23-23 are oscillated, the ram 20 maintains a horizontal position and moves from a position partially beneath the apron 17 where one set of the teeth 21 is well within the ad jacent notches to a similar position .partially beneath the apron 18 where the remaining set of teeth 22 is well within the adjacent notches of the apron 18. It will be noted that in this transverse motion, the ram 20 moves in a substantially horizontal plane, but rises slightly at the center of its travel.
  • the levers 2323 at each end of the ram are joined at the lower ends by a link 25 and are further connected by a link 26 to a suitable adjustable-stroke drive, shown as a disc 27 driven, as from the stoker engine, and having an adjustable crank pin 28.
  • a suitable adjustable-stroke drive shown as a disc 27 driven, as from the stoker engine, and having an adjustable crank pin 28.
  • Thewater for the cooling of the ram may be supplied through suitable flexible pipes and the water may thereafter be passed through pipes 31 and 32 to the aprons 16, 17 and 18, thus making for economy in cooling water.
  • the above described clinker grinder may be modified as shown in Figure 3 so as to discharge beneathbut a single apron.
  • aprons 17 and 18' are provided, as before, with the exception that the apron 18' need have no notches in its lower edge.
  • a ram 20, carrying teeth 22, is mounted as before, for oscillation, except that a portion thereof at all times is beneath the apron 18'.
  • refuse is never discharged between the apron 18 and the ram 20, all discharge being effected at the lower edge of the apron 17.
  • a discharge mechanism the combination with an open-bottomed receptacle, two opposite sides thereof being notched at their lower edges, of a member substantially closing the bottom of said receptacle and provided with two setsof upstanding teeth in alinement with said notches respectively, parallel levers supporting said member for approximately horizontal movement, and means for moving said member to such an extent that said teeth sets alternately enter the associated notches, simultaneously exposing a discharge opening at the opposite side of said member.
  • a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending aprons defining a refuse receptacle, of a ram member disposed beneath said aprons and blocking in one position the free discharge of refuse therefrom, means supporting said ram memberfor approximately horizontal motion transverse to said aprons, and means for moving said ram member to such extent that discharge passages are alternately opened and closed at the opposite sides of "the bottom of the receptacle.
  • a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending aprons d'efining a refuse receptacle, said aprons being provided with fluid cooling means, of a ram member disposed beneath said aprons and blocking in one posit-ion the free discharge of refuse therefrom, means supporting said ram member for approximately horizontal motion transverse to said aprons, and means for moving said ram member to such extent that discharge passages are alternately opened and closed at the opposite sides of the bottom of the receptacle.
  • a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending aprons defining a refuse receptacle,.of a ram member disposed beneath said aprons and blocking in one position the free discharge of refuse therefrom, fluid'cooling means for said ram member, means supporting said ram member for approximately horizontal motion transverse to said aprons, and means for moving said ram member to such extent that dis-. charge passages are alternately opened and closed at the opposite. sides of the bottom of the receptacle.
  • a-refuse discharge mechanism for mechanical "stokers, the combination with two, fixed, spaced depending aprons defining a refuse receptacle, said aprons being provided with water cooling means, of a ram member "isposed beneath said aprons and blocking 1. one position the free discharge of refuse therefrom, fluid cooling means for said ram member, meanssupporting said ram member for approximately horizontal motion transverse to said aprons, and means for moving said ram member to such extent that discharge passages are alternately opened and closed at the opposite sides of the bottom of said receptacle.
  • a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending aprons defining a refuse receptacle, each of said'aprons being provided with notches in the lower edge thereof, of a ram member disposed beneath said aprons and substantially block- 76 ing the free exit of refuse therefrom, upstanding teeth members on said ram'memher in alinement withrespective notches of said aprons, a system of levers supporting said ram member and permitting motion 84D thereof transverse to said aprons and approximately in a horizontal plane, and means for oscillating said levers to such an extent as to alternately expose a discharge. opening at the lower edge of each apron, 85 simultaneously causing the teeth at the op posite edge of the ram member to enter the adjacent notches.
  • a refuse discharge mechanism for mechanical stokers, the combination with on two, fixed, dependingspaced aprons defining a refuse receptacle, each of said aprons being provided with notches in the lower edge thereof, of a ram member disposed beneath said member and substantially blocking the free exit of refuse therefrom, said ram member being provided with two sets of upstanding teeth in substantial alinement respectively with the adjacent notches in said aprons, two sets of horizontally perforated levers disposed beneath said ram member and oscillatable 'in planes normal to said aprons, said levers supporting said ram members and permitting motion thereof transverse to said aprons, said ram remaining at all times approximately horizontal but rising and falling to a sli ht ex-, tent in different parts of. its travel, and
  • a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending water-cooled aprons defining a refuse receptacle, of a Water-cooled ram member disposed beneath sai'd'aprons and substantially blocking in one position the free exit of refuse-therefrom, a system of levers supporting said ram "member andpermitting motion thereof transverse to said aprons and approximately in a horizontal plane, and means for oscillating said levers to such an extent as to alternately open and close a discharge passage at the lower edge of each apron.
  • a refuse discharge mechanism for mechanical stokers the combination with two, fixed, depending spaced water-cooled aprons defining a refuse receptacle, of a water-cooled ram member disposed beneath said receptacle and substantially blocking in one position the free exit of refuse therefrom, two sets of horizontally pivoted levers disposed beneath said ram member and oscillatable in planes transverse to said aprons, said levers supporting said ram member and permitting motion thereof transverse to said aprons, said ram remaining at all times approximately horizontal but risingand falling to a slight extent in different parts of its travel, and means for moving said ram member and 'levers to such an extent as to alternately open and close discharge passages at the lower edges of said aprons.
  • a refuse discharge mechanism for mechanical stokers, the combination with a depending apron defining one side of a refuse receptacle, said apron being provided with notches in the lower edge thereof, of an approximately horizontally moving ram member disposed below the lower edge of said apron and having upstanding teeth in substantial alinement with the respective notches, and means for oscillating said ram member to such an extent as to periodically expose a refuse discharge opening between said ram member and the lower edge of said apron, and in the intervening periods to cause said teeth to move into and out of said notches.

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  • Engineering & Computer Science (AREA)
  • Food Science & Technology (AREA)
  • Incineration Of Waste (AREA)

Description

Aug. 11, 1925. 1,548,834,
R A. FORESMAN ASH DISCHARGE AND CLINKERYGRINDER STRUCTURE Filed March 5, 1921 fivberiA Wreaman I I N V E N T O R A'TTORNEY new Aug. n, 1925.
nonnnr a. roansMAN, or Moons; PENNSYLVANIA, AssIsNon r'o wnsrrnenousn ELECTRIC AND MANUFACTURING COMPANY, a CORPQTION or rnNNsYLvANra.
ASH-DISC =1 RGE AND CLINKER-GJRINDER STRUCTU.
Application filed March 3, 1921. Serial No. 449,591.
r the mechanically stoked type, and it has for its object to provide apparatus of the character designated which shall be simple and inexpensive and rugged in construction and effective in operation, particularly in that it permits ready control of the rate of refuse discharge as determined by different characters of fuel. I
in the accompanying drawings, Fig. 1
'. is'a side view, partially in section and partially in elevation, of a mechanical stoker of the underfeed type provided-with discharge mechanism constructed in accordance with my invention.
Figure 2 is a fragmentary view, in eleva tion, of a portion of the discharge mechanism, being taken on the plane I][H in Figure 1; and I Figure 3 is a detail view, partially in section and partially in elevation, of a modification of the apparatus shown in Figure 1.
In the operation of boiler furnaces, particularly those of the mechanical stoker type wherein large quantities of fuel are consumed, it is necessary to provide means for the disposal of'relatively large amounts of refuse at a uniform rate, which rate must be readily modified to care for varying amounts of refuse, as when shifting from a high ash coal to a low ash coal, or vice versa.
This problem is complicated by the fact that certain coals tend to, form large, troublesome clinkers because of the fusion of the ash and it is necessary to provide apparatus which shall be capable of breaking up these clinkers for the ready disposal thereof.
Furthermore, in order to increase the combustion rate of the furnaces, it is desir able to continue combustion, not only down to, but over the ash-disposal mechanism and the apparatus disclosed by me is so constructed, in the arrangement and configuration of parts, that active combustion may take place thereover without damage thereto or malfunction thereof. v
Referring to the accompanying drawing for a more detailed understanding of my invention, I show a stoker of conventional. underfeed type at 10 in Figure 1, this Stoker comprising a fuel-holding hopper 11, a fuel I supply and ram 12 and combustion tuyeres 13, all of which may be of any desired type,
as'will be understood by those versed in the art.
is bounded by a front wall 14 and at the rear by a wall 14: disposed at the foot of which is a refuse-discharge hopper 15 formed by aprons 16 and 17 depending from the lower edge of the active combustion grate and a similar apron 18 depending from the lower edge of the wall 14.. These aprons are preferably formed hollow for water cooling, but this feature is not an essential part of my invention.
The combustion space for the stoker 10 The aprons 17 and 18 are deeply notched 'at their lower edges, as shown at 19 in Figures 1 and '2, and a ram 20 is mounted for transverse movement beneath the aprons 17 and 18. The ram 20 comprises a main body portion, preferably formedhollow for the circulation of a suitable .cooling medium therethrough and having an upstanding fuel-agitating member 21 and two rows of crushing teeth 22, 22 at the sides thereof. These teeth are in alinement with the respective notches of the aprons 17 and 18, all for a purpose to be hereinafter pointed out.
The ram 20 is mounted on two sets" of vertically disposed levers '2323, these levers being pivotally mounted at 24--24. The arrangement is such that as the levers 23-23 are oscillated, the ram 20 maintains a horizontal position and moves from a position partially beneath the apron 17 where one set of the teeth 21 is well within the ad jacent notches to a similar position .partially beneath the apron 18 where the remaining set of teeth 22 is well within the adjacent notches of the apron 18. It will be noted that in this transverse motion, the ram 20 moves in a substantially horizontal plane, but rises slightly at the center of its travel. The levers 2323 at each end of the ram are joined at the lower ends by a link 25 and are further connected by a link 26 to a suitable adjustable-stroke drive, shown as a disc 27 driven, as from the stoker engine, and having an adjustable crank pin 28.
Thewater for the cooling of the ram may be supplied through suitable flexible pipes and the water may thereafter be passed through pipes 31 and 32 to the aprons 16, 17 and 18, thus making for economy in cooling water.
Having thus described the arrangement of a mechanism constructed in accordance with my invention, the operation thereof is as follows: The stoker having been started into operation, the fuel passes down over the active grate surface 13 and-is largely consumed and the refuse, carrying a small portion of combustible, falls into and partially fills the hopper formed by the aprons 16, 17 and 18. The small oscillation of the ram 20 causes the refuse in the lower portion of this hopper to be discharged, first beneath the apron 17 and then beneath the apron 18. The refuse body is moved and broken up by the upstanding member 21 and clinkers are caught between the aprons 17, 18 and the cooperating teeth 22, thus being crushed for discharge through the relatively small discharge openmgs 19 in the lowermargins of the aprons 17 and 18.
The movement of the teeth 22 into the adjacent notches of the water cooled aprons insures that these teeth shall be clear at the end of each stroke. a
The entire mass of refuse is maintained in a broken-up condition, not only by the transverse motion of the ram 20 but also by the slight rise and fall thereof imparted thereto by the specific link mechanism. disclosed.
The passage of air between the ram 20 and the lower edges of the aprons 17 and 18 permits the burning of the small portion of combustible remaining in the refuse discharge from the active grate surface 13.
If desired, the above described clinker grinder may be modified as shown in Figure 3 so as to discharge beneathbut a single apron. Thus aprons 17 and 18' are provided, as before, with the exception that the apron 18' need have no notches in its lower edge. A ram 20, carrying teeth 22, is mounted as before, for oscillation, except that a portion thereof at all times is beneath the apron 18'. Thus refuse is never discharged between the apron 18 and the ram 20, all discharge being effected at the lower edge of the apron 17.
While I have shown my invention in but two forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon ,as are imposed by the prior art or as are specifically set forth in the appended claims.
amasse What I claim is: 1. In a discharge mechanism, the combination with an open-bottomed receptacle,
'two opposite walls thereof being notched at member so that said teeth sets alternately I enter the respectively associated notches, substantially simultaneously exposing a discharge opening at the opposite side of said member.
2. In a discharge mechanism, the combination with an open-bottomed receptacle, two opposite sides thereof being notched at their lower edges, of a member substantially closing the bottom of said receptacle and provided with two setsof upstanding teeth in alinement with said notches respectively, parallel levers supporting said member for approximately horizontal movement, and means for moving said member to such an extent that said teeth sets alternately enter the associated notches, simultaneously exposing a discharge opening at the opposite side of said member.
. 3. In a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending aprons defining a refuse receptacle, of a ram member disposed beneath said aprons and blocking in one position the free discharge of refuse therefrom, means supporting said ram memberfor approximately horizontal motion transverse to said aprons, and means for moving said ram member to such extent that discharge passages are alternately opened and closed at the opposite sides of "the bottom of the receptacle.
4. In a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending aprons d'efining a refuse receptacle, said aprons being provided with fluid cooling means, of a ram member disposed beneath said aprons and blocking in one posit-ion the free discharge of refuse therefrom, means supporting said ram member for approximately horizontal motion transverse to said aprons, and means for moving said ram member to such extent that discharge passages are alternately opened and closed at the opposite sides of the bottom of the receptacle.
5. In a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending aprons defining a refuse receptacle,.of a ram member disposed beneath said aprons and blocking in one position the free discharge of refuse therefrom, fluid'cooling means for said ram member, means supporting said ram member for approximately horizontal motion transverse to said aprons, and means for moving said ram member to such extent that dis-. charge passages are alternately opened and closed at the opposite. sides of the bottom of the receptacle.
6. In a-refuse discharge mechanism for mechanical "stokers, the combination with two, fixed, spaced depending aprons defining a refuse receptacle, said aprons being provided with water cooling means, of a ram member "isposed beneath said aprons and blocking 1. one position the free discharge of refuse therefrom, fluid cooling means for said ram member, meanssupporting said ram member for approximately horizontal motion transverse to said aprons, and means for moving said ram member to such extent that discharge passages are alternately opened and closed at the opposite sides of the bottom of said receptacle.
7. In a refuse discharge mechanism' for mechanical stokers, the combination with two, fixed, spaced depending aprons defin ing a refuse receptacle, said aprons being transversely notched at their lower edges,
of a ram member disposed beneath said aprons and provided with sets of upstande mg teeth in alinement with the respective notches, means supporting said ram membe: and permitting approximately horizontal movement transverse to said aprons, and
means for so moving said ram member that teeth alternately enter the notches of each apron, simultaneously exposing a discharge opening at the lower edge of the apron.
8. In arefuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending aprons defining a refuse receptacle, of a ram member disposed beneath said aprons and substantially blocking in one position the free'exit "of refuse therefrom, a-system of levers supporting said ram member and permitting mbtion thereof transverse to said aprons and approximately in a horizontal plane, and meansfor oscillating said levers to such an extent as to alternately open and close a discharge passage at the lower edge ofeach aprom' v QQIn a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, depending spaced aprons defin-- mg a refuse receptacle, of a ram member disposedbeneath said receptacle and substantially blocking in one position the free exit of refuse theref'ronfi-two sets of horizontally pivoted levers disposed beneath said ram member and oscillatable in planes transverse to said aprons, said levers supporting said ram member and permitting motion thereof transverse to said aprons, said ram'remaining at all times approximately horizontal but rising and fallin to a slight extent in difi'erentparts of its travel, and means for :moving said ram" member and levers to such an extent as to alternately. open and close discharge passages at the lower edges of said aprons.
10. In a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending aprons defining a refuse receptacle, each of said'aprons being provided with notches in the lower edge thereof, of a ram member disposed beneath said aprons and substantially block- 76 ing the free exit of refuse therefrom, upstanding teeth members on said ram'memher in alinement withrespective notches of said aprons, a system of levers supporting said ram member and permitting motion 84D thereof transverse to said aprons and approximately in a horizontal plane, and means for oscillating said levers to such an extent as to alternately expose a discharge. opening at the lower edge of each apron, 85 simultaneously causing the teeth at the op posite edge of the ram member to enter the adjacent notches. e 1
11. In a refuse discharge mechanism for mechanical stokers, the combination with on two, fixed, dependingspaced aprons defining a refuse receptacle, each of said aprons being provided with notches in the lower edge thereof, of a ram member disposed beneath said member and substantially blocking the free exit of refuse therefrom, said ram member being provided with two sets of upstanding teeth in substantial alinement respectively with the adjacent notches in said aprons, two sets of horizontally perforated levers disposed beneath said ram member and oscillatable 'in planes normal to said aprons, said levers supporting said ram members and permitting motion thereof transverse to said aprons, said ram remaining at all times approximately horizontal but rising and falling to a sli ht ex-, tent in different parts of. its travel, and
-means'-for moving said ram' members and levers to such an extent as to alternately ex- .1110
pose discharge openings at-the lower edges of said aprons, simultaneously causing the teeth at the other side of said ram member to enter the adjacent notches.
12. In a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, spaced depending water-cooled aprons defining a refuse receptacle, of a Water-cooled ram member disposed beneath sai'd'aprons and substantially blocking in one position the free exit of refuse-therefrom, a system of levers supporting said ram "member andpermitting motion thereof transverse to said aprons and approximately in a horizontal plane, and means for oscillating said levers to such an extent as to alternately open and close a discharge passage at the lower edge of each apron.
13;. In a refuse discharge mechanism for mechanical stokers, the combination with two, fixed, depending spaced water-cooled aprons defining a refuse receptacle, of a water-cooled ram member disposed beneath said receptacle and substantially blocking in one position the free exit of refuse therefrom, two sets of horizontally pivoted levers disposed beneath said ram member and oscillatable in planes transverse to said aprons, said levers supporting said ram member and permitting motion thereof transverse to said aprons, said ram remaining at all times approximately horizontal but risingand falling to a slight extent in different parts of its travel, and means for moving said ram member and 'levers to such an extent as to alternately open and close discharge passages at the lower edges of said aprons.
14. In a refuse discharge mechanism for mechanical stokers, the combination with a depending apron defining one side of a refuse receptacle, said apron being provided with notches in the lower edge thereof, of an approximately horizontally moving ram member disposed below the lower edge of said apron and having upstanding teeth in substantial alinement with the respective notches, and means for oscillating said ram member to such an extent as to periodically expose a refuse discharge opening between said ram member and the lower edge of said apron, and in the intervening periods to cause said teeth to move into and out of said notches. I
In testimony whereof, I have hereunto subscribed my name this 25 day of February, 1921.
ROBERT A. FORESMAN.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2636484A (en) * 1949-04-08 1953-04-28 Babcock & Wilcox Co Steam generator

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2636484A (en) * 1949-04-08 1953-04-28 Babcock & Wilcox Co Steam generator

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