GB2127536A

GB2127536A - Grates for coal or wood

Info

Publication number: GB2127536A
Application number: GB08326012A
Authority: GB
Inventors: Malcolm Edwin Wood
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-09-29
Filing date: 1983-09-28
Publication date: 1984-04-11
Also published as: GB8326012D0

Abstract

A stove or boiler has a grate suitable for different fuels e.g. coal and wood, the grate having a plurality of firebars which in the preferred embodiment are cantilevered from two opposed and interleaving grate halves (1A, Fig. 1), 1B. The grate halves are relatively movable to vary and set the spacing between them, by a control mechanism coupled to an operating handle externally of the stove or boiler. The same control mechanism can be used as a riddling device. <IMAGE>

Description

SPECIFICATION Apparatus for burning solid fuels This invention relates to apparatus which is capable of burning solid fuels of differing characteristics, and is particularly directed to a stove or boiler having a grate suitable for coal or coal-based fuels and for wood.

According to this invention apparatus for burning solid fuels includes a grate comprising a plurality of firebars which are movable relative to each other to vary the spacing between them. The relative position of the firebars is controlled by means of a mechanism coupled to a handle projecting preferably from the front of the apparatus for manual operation. This mechanism may also be used as a riddling device whereby the firebars can be shaken back and forth to allow ash and unused fuel to drop through the grate.

In a preferred embodiment the grate comprises two relatively movable interleaving halves, each half being in the form of a comb, with a row of tapered, cantilevered firebars extending from an outer side member towards the other half. Each tapered firebar belonging to one half of the grate extends into a correspondingly tapered recess formed by a pair of adjacent firebars of the other half extending in the opposite direction. For burning wood or peat economically, it is necessary to build up an ash bed on the grate. This is accomplished by bringing the two grate halves towards each other, to a closed position in which the spacing between the opposing sets of firebars is relatively small.Conversely, efficient burning of coal-based fuels requires a more open grate, so in this case the grate halves are moved apart to increase the spacing between the tapered firebars allowing an increased supply of air from beneath.

Variation of the air supply to the fuel bed by adjusting the position of the firebars enables the same mechanism to be used also as a riddling device. In addition it is possible to change from one fuel to another without dousing the fire, and without removing or adding components.

A preferred embodiment of the invention is illustrated by way of example in the accompanying drawings.

Figure 1 is a side elevation of the lower portion of a stove with the nearest side wall removed to show the grate 1 A, 1 B and its associated control mechanism. This should be viewed in conjunction with Figures 2a which is a plan view of the grate showing the two grate halves 1 A and 1 B including tapered firebars, and Figure 3a which is a front elevation of the apparatus of Fig. 1. In Fig. 3a, the front portion of the stove and parts of the grate have been removed for clarity.

Referring to these three figures, the grate 1 A, 1 B is supported on a transverse front slide 2 and a transverse back slide 3 with the cantilevered firebars extending transversely and inwardly in an interleaving arrangement. A handle 4, attached to a control arm 5, projects at the front of the stove and is coupled to a riddling mechanism for causing the two grate halves 1 A and 1 B to execute transverse movements in opposing directions when the handle 4 is moved from side to side. The control arm 5 is pivotable about a pivot rod 6 defining a vertical axis and slides between a pair of rails 7 and 8 mounted on an underside wall 9 of the stove. The arm 5 is coupled to a crank 10 mounted in a pivotable T-piece 11 at the rear of the stove.It will be seen that side to side movement of the handle 4 results in short clockwise and anti-clockwise oscillations of the T piece 11 about a horizontal axis. This movement is transferred to a pair of lever assemblies 1 2A and 1 2B (one only shown in Fig. 1) by means of connecting rods 1 4A and 1 4B mounted on pins 1 6A and 1 6B on the T-piece 11 and attached to brackets 1 8A and 1 8B on the lever arms. Each lever arm pivots in a front bearing 20 and rear bearing 21. The attachment of the connecting rods to opposite arms of the T-piece 11 means that the two lever assemblies pivot either towards or away from each other when the handle 4 is reciprocated.These opposing movements are reproduced by the grate halves 1 A and 1 B since each lever assembly has an upstanding lever arm 22A or 22B fitted loosely in a hole 24A and 24B in the corresponding grate half.

Operation of the mechanism is such that firstly vigorous side to side movement of the handle 4 results in reciprocating movement of the grate halves in opposite directions, so as to shake any material on the grate down between the firebars into the space beneath. Secondly when the fire is alight, the space between the firebars is adjusted according to the fuel being used by setting the handle 4 to a predetermined position corresponding to the required spacing.

The individual parts of the mechanism referred to above are illustrated in Figs 1 to 14 which are annotated according to the parts shown.

1. Apparatus for burning solid fuels includes a grate comprising a plurality of firebars and a control means for moving the firebars relative to one another to vary the spacing between them.

2. Apparatus according to claim 1 wherein the control means comprises a mechanism coupled to a handle accessible externally of the apparatus for manual operation.

3. Apparatus according to claim 1 or claim 2 wherein the grate comprises two relatively movable interleaving halves, each half in the form of a comb, with a row of tapered, cantilevered firebars extending from an outer side member toward the other half.

4. Apparatus according to claim 3 wherein each tapered firebar belonging to one half of the grate extends into a corresponding tapered recess formed by a pair of adjacent firebars of the other hand extending in the opposite direction.

5. Apparatus according to claim 3 or claim 4 wherein relative movement of the two grate halves occurs in the same plane, in sense to withdraw or insert the tapered firebars belonging to one half of the grate respectively from or into

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Apparatus for burning solid fuels This invention relates to apparatus which is capable of burning solid fuels of differing characteristics, and is particularly directed to a stove or boiler having a grate suitable for coal or coal-based fuels and for wood. According to this invention apparatus for burning solid fuels includes a grate comprising a plurality of firebars which are movable relative to each other to vary the spacing between them. The relative position of the firebars is controlled by means of a mechanism coupled to a handle projecting preferably from the front of the apparatus for manual operation. This mechanism may also be used as a riddling device whereby the firebars can be shaken back and forth to allow ash and unused fuel to drop through the grate. In a preferred embodiment the grate comprises two relatively movable interleaving halves, each half being in the form of a comb, with a row of tapered, cantilevered firebars extending from an outer side member towards the other half. Each tapered firebar belonging to one half of the grate extends into a correspondingly tapered recess formed by a pair of adjacent firebars of the other half extending in the opposite direction. For burning wood or peat economically, it is necessary to build up an ash bed on the grate. This is accomplished by bringing the two grate halves towards each other, to a closed position in which the spacing between the opposing sets of firebars is relatively small.Conversely, efficient burning of coal-based fuels requires a more open grate, so in this case the grate halves are moved apart to increase the spacing between the tapered firebars allowing an increased supply of air from beneath. Variation of the air supply to the fuel bed by adjusting the position of the firebars enables the same mechanism to be used also as a riddling device. In addition it is possible to change from one fuel to another without dousing the fire, and without removing or adding components. A preferred embodiment of the invention is illustrated by way of example in the accompanying drawings. Figure 1 is a side elevation of the lower portion of a stove with the nearest side wall removed to show the grate 1 A, 1 B and its associated control mechanism. This should be viewed in conjunction with Figures 2a which is a plan view of the grate showing the two grate halves 1 A and 1 B including tapered firebars, and Figure 3a which is a front elevation of the apparatus of Fig. 1. In Fig. 3a, the front portion of the stove and parts of the grate have been removed for clarity. Referring to these three figures, the grate 1 A, 1 B is supported on a transverse front slide 2 and a transverse back slide 3 with the cantilevered firebars extending transversely and inwardly in an interleaving arrangement. A handle 4, attached to a control arm 5, projects at the front of the stove and is coupled to a riddling mechanism for causing the two grate halves 1 A and 1 B to execute transverse movements in opposing directions when the handle 4 is moved from side to side. The control arm 5 is pivotable about a pivot rod 6 defining a vertical axis and slides between a pair of rails 7 and 8 mounted on an underside wall 9 of the stove. The arm 5 is coupled to a crank 10 mounted in a pivotable T-piece 11 at the rear of the stove.It will be seen that side to side movement of the handle 4 results in short clockwise and anti-clockwise oscillations of the T piece 11 about a horizontal axis. This movement is transferred to a pair of lever assemblies 1 2A and 1 2B (one only shown in Fig. 1) by means of connecting rods 1 4A and 1 4B mounted on pins 1 6A and 1 6B on the T-piece 11 and attached to brackets 1 8A and 1 8B on the lever arms. Each lever arm pivots in a front bearing 20 and rear bearing 21. The attachment of the connecting rods to opposite arms of the T-piece 11 means that the two lever assemblies pivot either towards or away from each other when the handle 4 is reciprocated.These opposing movements are reproduced by the grate halves 1 A and 1 B since each lever assembly has an upstanding lever arm 22A or 22B fitted loosely in a hole 24A and 24B in the corresponding grate half. Operation of the mechanism is such that firstly vigorous side to side movement of the handle 4 results in reciprocating movement of the grate halves in opposite directions, so as to shake any material on the grate down between the firebars into the space beneath. Secondly when the fire is alight, the space between the firebars is adjusted according to the fuel being used by setting the handle 4 to a predetermined position corresponding to the required spacing. The individual parts of the mechanism referred to above are illustrated in Figs 1 to 14 which are annotated according to the parts shown. CLAIMS

5. Apparatus according to claim 3 or claim 4 wherein relative movement of the two grate halves occurs in the same plane, in sense to withdraw or insert the tapered firebars belonging to one half of the grate respectively from or into corresponding recess between the firebars of the other half of the grate.

6. Apparatus according to claim 5 wherein both halves of the grate are movable by a mechanism coupled to a common handle and comprising a crank which is pivotable upon operation of the handle to displace two crank arms linked one to each of the grate halves, in opposite directions.

7. Apparatus for burning solid fuels and including a grate constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.