JPH1019212A - Stoker driving mechanism of refuse incinerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a drive shaft using common path even when a refuse incinerator is increased in size and the zone area is increased by arranging the drive shaft in a split manner in the width direction of the incinerator in a drive mechanism in which a frame is moved in the direction orthogonal to the incinerator width direction by rotative motion of the drive shaft. SOLUTION: A stoker mechanism 1 is split into two parts in the incinerator width direction, and each split stoker mechanism 1 is provided with a chive mechanism 7 to reciprocate a frame 6 on a hearth support body 5. A grate separation body 20 is extended over the whole length of the hearth support body 5 between the split heart support bodies, and a fire bed formed on the stoker mechanism 1 is split into two parts. The grate 2 and a fixed grate 3 are also split into two parts. The flame 6 can be easily split in the incinerator width direction by splitting a drive shaft into two parts. The drive shaft can be manufactured using common parts without increasing the output of the drive source even when the zone area is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stoker drive mechanism for a refuse incinerator, and more particularly, to a frame, a plurality of grate, and a frame mounted and supported in a state where the plurality of grate are individually positioned. A refuse incinerator that is provided in a furnace width direction and includes a drive shaft connected to the frame via a link mechanism, and the frame is moved in a direction orthogonal to the furnace width direction by a rotational movement of the drive shaft. And a stoker drive mechanism.

[0002]

2. Description of the Related Art Conventionally, in a stoker drive mechanism of a garbage incinerator having a movable grate, as shown in FIG. 8, a movable grate formed on the stoker mechanism 1 has a plurality of fixed positions. For the fixed grate 3 and the fixed grate 3,
A plurality of grate 2 are arranged side by side in a direction perpendicular to the furnace width direction and slide relative to the fixed grate 3. The fixed grate 3 is fixedly supported on a grate support 5, and the grate 2 is placed and supported on a frame 6 while being separately positioned. The frame 6 is provided with a frame guide 1 of a frame support mechanism 15 attached to the grate support 5 to move the movable grate 4 relative to the fixed grate 3.
It is provided so as to be movable along a direction perpendicular to the furnace width direction along 5a. In order to move and drive the frame 6, one drive shaft 9 connected to the frame 6 via a link mechanism and disposed in the furnace width direction with respect to the frame 6 is supported by the grate support. A bearing portion 9a is provided on a bearing B attached to the body 5 so as to be rotatably supported around the axis of the drive shaft 9, and the movable frame 6 is moved by the reciprocating rotation of the drive shaft 9. It is configured to reciprocate in the moving direction of the lattice 4. The reciprocating rotation of the drive shaft 9 is performed by a hydraulic cylinder mechanism 8 pivotally mounted on the grate support 5.
It is performed by The drive shaft 9 is connected to the stoker mechanism 1.
The bearing B is attached to the grate support 5 of the stoker mechanism 1 as described above in relation to the arrangement of the wind box 10 so that the bearing B is provided in a narrow portion outside the wind box 10. Be placed. This is because a preheated combustion gas of 200 to 250 ° C. is introduced into the wind box 10, and the garbage burning in the wind box 10 is discharged from the grate for burning the trash on the stoker mechanism 1. Since the ash falls, the bearing portion 9a is not affected by the heat of the combustion gas, and the falling ash is deposited on the bearing portion 9a or the ash bearing portion 9a.
It is also to prevent the intrusion into.

[0003]

In the stoker drive mechanism of the above-mentioned conventional refuse incinerator, only one drive shaft 9 is provided for the frame 6.
For example, if the area of the grate formed by the movable grate 3 mounted and supported on the frame 6 to be driven (hereinafter, referred to as a zone area) is increased by increasing the furnace width, the driving load increases. Therefore, the torque applied to the drive shaft 9 increases, and it is necessary to increase the shaft diameter. For example, if the zone area is tripled, the shaft torque applied to the drive shaft 9 becomes about 1.6 times, and the required shaft diameter corresponding thereto becomes about twice. Therefore, in the conventional stalker drive mechanism, even if a safety factor is given to the design of the drive shaft 9 to provide a margin, if the furnace width is increased, the zone area becomes larger, and as a result, the drive Exceeding the range of the allowance with respect to the shaft diameter of the shaft 9, the shaft diameter of the drive shaft 9 has to be increased, and there is a problem that it is difficult to share parts. Therefore, the stoker drive mechanism of the refuse incinerator according to the present invention solves the above-described problems, and enables a stoker drive mechanism capable of manufacturing a drive shaft using common parts even when the refuse incinerator is enlarged and the zone area is increased. The purpose is to provide a mechanism.

[0004]

[Means for Solving the Problems]

[First characteristic configuration] A first characteristic configuration of the stoker driving mechanism of the refuse incinerator according to the present invention for the above-mentioned object is, as described in claim 1, a drive shaft connected to the frame via a link mechanism. The point is that it is divided and arranged in the furnace width direction. [Effects of First Feature Configuration] According to the first feature configuration, it is possible to share the load of the frame driving applied when driving the frame to each of the drive shafts, and to prevent the difference in the applied shaft torque from occurring. If the drive shaft is divided, there is no change in the power required to drive each coaxial, despite the expansion of the zone area, and it is possible to suppress an increase in the torque applied to each drive shaft. It becomes possible to keep it within a margin derived from the rate. For example, if the width of the furnace is doubled and the drive shaft is divided into two, the drive power of the power source for driving each drive shaft can be used even if the original drive shaft before being doubled is used as it is. Remains the same, so that the torque applied to each drive shaft reduces the furnace width by 2
It is the same as the torque before doubling. Furthermore, by dividing the drive shaft in the furnace width direction, it is easy to divide the frame in the furnace width direction.If the frame is divided, it is caused by uneven conveyance in the furnace width direction accompanying the furnace width expansion. It is possible to reduce uneven distribution of dust (that is, positional variation of dust quality or quantitative positional variation of dust and positional variation of the thickness of the dust layer resulting therefrom). As a result, it is possible to manufacture the drive shaft using common components without increasing the output of the drive source even if the zone area is increased.

[Second characteristic configuration] According to a second characteristic configuration of the stoker drive mechanism of the refuse incinerator according to the present invention, the combustion gas is guided from below the grate in the first characteristic configuration. Is formed in such a manner that a divided wind box is formed by dividing a wind box to be divided in the furnace width direction, and the bearing portion of the divided drive shaft is positioned outside each of the divided wind boxes. [Effects of the second characteristic configuration] According to the second characteristic configuration, since the bearings of the respective drive shafts are located outside each of the divided wind boxes, in the case of the undivided wind box, if the drive shafts temporarily Assuming that the bearing portion of the portion is disposed in the wind box, the bearing portion disposed in the wind box is exposed to the preheated combustion gas and receives ash falling from the gap of the grate. Therefore, it is possible that the number of times of maintenance of the bearings disposed in the wind box may increase.However, by avoiding this, it is possible to perform maintenance work on all the bearings outside the wind box. ,and,
Since the bearing is not exposed to the heated combustion gas, the life of the bearing is not reduced. as a result,
In addition to the operation and effect of the first characteristic configuration, maintenance of the drive shaft is facilitated.

[Third characteristic configuration] A third characteristic configuration of the stoker drive mechanism of the refuse incinerator of the present invention for the above purpose is as follows.
As described in claim 3, a plurality of drive shafts connected to the frame via a link mechanism are arranged in parallel in a direction orthogonal to the furnace width direction, and each of the plurality of drive shafts is provided separately from the frame. That is, they are connected via a link mechanism. [Third characteristic configuration and operation and effect] According to the third characteristic configuration, the required shaft diameter does not largely change as in the operation and effect of the first characteristic configuration, and similar to the second characteristic configuration, The bearing portion of the drive shaft can be located outside the wind box, and it is possible to avoid heat being applied to the bearing portion and ash falling. Furthermore, by arranging individual drive sources for each drive shaft, it is possible to reduce the required output of each drive source and prevent the required output of each drive source from increasing as the frame's drive load increases. It is possible to do. Further, if each drive shaft is power-coupled (for example, link-coupled), a drive source may be provided for each power-coupling unit, so that the frame can be driven by a small number of drive sources. As a result, even if the zone area is increased, the drive shaft can be manufactured using common parts, and at the same time, the maintenance of the drive shaft portion becomes easy.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of an embodiment of the stoker drive mechanism for a refuse incinerator according to the present invention will be described below with reference to the drawings, using an example applied to a refuse incinerator having a nominal furnace width of 12 m. . FIG. 1 shows a cross section in the furnace width direction of a garbage incinerator for explaining a position embodiment of a stalker drive mechanism of the present invention, and FIG. 2 is a perspective view showing an example of a specific configuration of the stalker drive mechanism. Was.

A stoker mechanism 1 is provided in the refuse incinerator. A movable grate formed on the stoker mechanism 1 includes a plurality of grate 2 arranged in a direction orthogonal to the furnace width direction. It is formed with a plurality of fixed grate 3. The fixed grate 3 is fixedly supported on a grate support 5 of the stoker mechanism 1, and the grate 2 is reciprocally movable along an upper surface of the fixed grate 3. It is supported in a state where it is positioned on a frame 6 that is movably supported by a grate support 5 via a frame support mechanism 15. Specifically, both the grate 2 and the fixed grate 3 are composed of a plurality of grate pieces 4 arranged in the furnace width direction, and each grate piece 4 is attached to each of the grate pieces 4 as shown in FIG. A fitting recess formed at a lower portion of the provided vertical rib is attached to a support rod R provided on the upper surface of the grate support 5 and the upper surface of the frame 6 from above from outside.

The stoker mechanism 1 is formed into two parts each having a width of 6 m in the furnace width direction, and the divided stoker mechanisms 1 are driven by the fire bed support 5 to reciprocately drive the frame 6. A mechanism 7 is provided. As shown in FIGS. 2 and 3, between the divided grate supports 5, along the garbage transport direction by the stoker mechanism 1, over the entire length of the grate support 5. The grid separator 20 is extended, and the grate formed on the stoker mechanism 1 is divided into two regions each having a width of 6 m. Along with this, the grate 2 and the fixed grate 3 are also provided in two parts, and the grate pieces 4 forming the fixed grate 3 in contact with the grate separator 20 are separated from the grate separator 20. The grate piece 4 that is fixed on the grate support 5 and forms the grate 2 disposed closest to the grate separator 20 slides on the grate separator 20. It is movably fixed on the frame 6. The grate 2 and the fixed grate 3 are each elastically pressed toward the grate separator 20 from the furnace wall side. Since the grate is divided into regions as described above, the uneven distribution of dust in each region can be maintained at a level comparable to the conventional case.

In accordance with the stoker mechanism 1, the wind box 10 is also divided into two, and the divided wind boxes 10A are opened in the respective stoker mechanisms 1. That is, the lower end of the grate support 5 is located outside the split wind box 10A. An air duct 11 for combustion gas is branched and connected to the divided wind box 10A, and a damper mechanism 12 is provided for each of the ducts.
In this way, the air supply amount can be controlled for each area of the fire bed.

As shown in FIGS. 2 and 3, the fire grate separator 20 includes vertical wall portions 20a on both side walls of the furnace.
The upper end of the vertical wall 20a, that is, the grate separator 20
The upper surface position of the grate 2 is the upper edge of the grate 2, that is, the most advanced end of the grate 2, in other words, the highest position of the upper surface of the grate 2 at the position where the grate 2 is highest. Higher. Further, the upper surface of the fire grate separator 20 has a ridge line so as to slide dust toward the grate 1 on both sides, and is inclined so as to descend toward both the vertical wall portions 20a. 20b having a smooth outer surface
The dust falling along the roof portion 20b falls on the grate 2 or the fixed grate 3. Further, a downstream end wall portion 20c is provided at a downstream end portion of the grate separation body 20 in the dust transfer direction, and an upstream end wall portion 20d is provided at an upstream end portion of the grate separation member from the roof portion 20b. Then, the internal space is
b, both vertical wall portions 20a, 20a, both side end wall portions 20
c, 20d. The shape of the upper surface of the grate separator 20, that is, the shape of the roof portion 20 b is for preventing garbage being conveyed from stagnating on the grate separator 20, and The upper end of the part 20a is higher than the upper end of the grate 2
This is for preventing a gap from being formed between the grate 2 and the grate separation body 20 to bite dust or combustion residue.

As shown in FIG. 4, the grate separator 20 is attached to the grate support 5 by a thin plate-made separator support member 22 so as to be displaceable in the furnace width direction. The separator support member 22 forms the lower surface of the grate separator 20, and the inner space is a closed space, near the end of the downstream end wall 20 c and the end of the upstream end wall 20 d. Are provided at respective positions, and a cooling gas passage 21 is formed inside the grate separator 20 and the separator support member 22. In order to supply the cooling gas flowing through the cooling gas passage 21 from one end thereof and discharge it from the other end toward the wind box 10 as a part of the combustion gas, the upstream end wall is provided. Opening 22a on the side of part 20d
Guides a part of the combustion gas supplied to the wind box 10 and sends out the combustion gas to the wind box 10 through the opening 22b on the downstream end wall 20c side. Is the cooling gas for the grate separator 20 (see FIG. 3). As a result, unnecessary cooling gas for cooling the grate separator 20 is not required, and there is no need to change the operating conditions of the furnace from the conventional one. As described above, since the grate separation body 20 is provided so as to separate the grate divided into regions, different conveyance control can be performed for each of the divided regions. Further, since the separating body 20 is fixed in position with respect to the grate, the separation body 20 serves as a conveyance resistor for the conveyed dust, and the contaminated dust on the grate can be stirred.

As shown in FIG. 6, the frame 6 is supported via a support roller 15b so as to be movable along a frame guide 15a of a frame support mechanism 15 attached to the grate support 5. As shown in FIG. 5, the hydraulic cylinder mechanism 8 is driven to reciprocate by a drive mechanism 7 that transmits the push-pull operation force of the hydraulic cylinder mechanism 8 through a link mechanism. The drive mechanism 7 is provided in each of the divided stoker mechanisms 1, and includes a hydraulic cylinder mechanism 8 pivotally attached to the grate support 5, and a split drive shaft 9 </ b> A that relays and transmits the output of the hydraulic cylinder mechanism 8. And a connecting rod 7c pivotally attached to the frame 6. The split drive shaft 9A
Is a structure in which the drive shaft 9 arranged in the furnace width direction is divided in the length direction along with the division of the stoker mechanism 1.
The split drive shaft 9A has a passive arm 7a and a drive arm 7b fixed to the split drive shaft 9A, and the passive arm 7a has an operating end of a cylinder rod 8a of the hydraulic cylinder mechanism 8. A link is formed by the cylinder rod 8a and the passive arm 7a, and one end of the drive arm 7b and the connecting rod 7c is pivotally connected. An end side is pivotally attached to the frame 6, and a link is formed by the drive arm 7b and the connecting rod 7c.
The frame 6 is driven to reciprocate by swinging a and b. The reciprocating driving force of the cylinder rod 8a of the hydraulic cylinder mechanism 8 is transmitted to the frame 6 through the reciprocating rotation of the split drive shaft 9A.

The split drive shaft 9A is connected to the grate support 5
The bearing portions 9a are fitted into bearings B respectively attached to the lower ends of both sides of the divided wind box 10A, and are rotatably supported by being sealed in a state of being penetrated through the divided wind box 10A. Are formed inside the divided grate support 5, and the bearings B are respectively arranged outside the divided wind box 10A. Therefore, while the drive shaft 9 is divided, the maintenance of the bearing B and the bearing portion 9a fitted therein can be performed outside the split wind box 10A.

As a result of the above construction, the nominal furnace width 12
m to form a grate in one region and reciprocate the frame 6 with one drive shaft 9 to convey the dust, the required output of the hydraulic cylinder mechanism 8 is 6739 Nm. The shaft diameter of the drive shaft 9 is 468 mm. Considering the safety factor for this required shaft diameter, about 56
A diameter of 0 mm is required, but the grate
And the drive shaft 9 is also divided to form a divided drive shaft 9A corresponding to a nominal furnace width of 6 m. As a result, the output of the hydraulic cylinder mechanism 8 that swings and drives the drive shaft 9 is 276.
0 Nm is sufficient, and the diameter of the divided drive shaft 9A is sufficient to be 335 mm even in consideration of the safety factor. Further, as a result of dividing the wind box 10 into a divided wind box 10A, the air volume can be controlled respectively as two regions in which the grate is divided into two in the furnace width direction. Even in the case where the deviation occurs, it is possible to suppress the deviation in both the drying and the combustion in the furnace width direction, and it is possible to keep the burn-out position of the dust at substantially the same position in the furnace width direction. Furthermore, since the grate separator 20 for dividing the area on the grate is provided, the agitation of the dust is improved by the resistance of the grate separator 20 to the transfer of the dust, and the drying state and the combustion state can be maintained well. It is now possible.

Next, another embodiment of the present invention will be described. <1> In the above embodiment, an example is shown in which the stoker drive mechanism of the present invention is applied to a garbage incinerator having a nominal furnace width of 12 m, but the numerical value of the nominal furnace width has no specific meaning, and Is arbitrary. Further, although the example in which the stoker mechanism 1 is divided into two is shown, the number of divisions may be three, and thereby uneven distribution of dust on the grate is suppressed. For example, if the above example is divided into three parts, a member having a nominal furnace width of 4 m can be used as a drive shaft member. In addition, nominal furnace width 2
When m is used as a reference, the drive shaft 9 may be divided into six parts. Accordingly, the stoker mechanism 1 can be divided into six parts. In this case, it is even better to provide five grate separators 20 side by side, and the divided wind box 10A also has six stoker mechanisms 1
It is even better to provide each of them. <2> In the above-described embodiment, an example in which the drive shaft 9 is divided into two in the furnace width direction is shown. However, as shown in FIG. Without dividing, the drive shafts arranged in a plurality of furnace width directions may be juxtaposed in a direction orthogonal to the furnace width direction. For example, as shown in FIG. 5, the first direction is orthogonal to the furnace width direction.
A drive shaft 9B and a second drive shaft 9C are provided, and the first drive shaft 9B is provided similarly to the split drive shaft 9A,
The drive shaft 9C is also configured in the same manner as the split drive shaft 9A, and the passive arm 7a of the second drive shaft 9C is link-connected to the passive arm 7a of the first drive shaft 9B using a connecting member 7d. The drive arm 7b of the two drive shaft 9C may be linked to the frame 6 by the connecting rod 7c similarly to the first drive shaft 9B. By doing so, the first and second drive shafts 9
The torque applied to the drive shafts B and 9C is halved as in the case of the split drive shaft 9A. Under the conditions in the above embodiment, the shaft diameters of both the drive shafts 9B and 9C are both 335 mm. It becomes possible to use a member of 6 m.
In the above embodiment, the nominal furnace width is described as 6 m. However, when the nominal furnace width is 2 m, the number of the drive shafts arranged in parallel may be increased to six. . In this case, the diameter of each drive shaft is 165 mm. <3> In the above <2>, the passive arm 7a of the second drive shaft 9C is connected to the passive arm 7a of the first drive shaft 9B by the connecting member 7.
Although the example in which the link is connected by using d is shown, the drive mechanism 7 is formed individually without connecting the first drive shaft 9B and the second drive shaft 9C, and the frame 6 is reciprocated. In this case, it is possible to reduce the capacity of each drive device, taking the hydraulic cylinder mechanism 8 as an example.
In this case, the number of drive shafts may of course be three or more, and when driving with three or more drive shafts, some of them are linked in the same manner as described in <2> above. They may be combined. <4> In the above-described embodiment, the example in which the stoker mechanism 1 is divided and the divided wind boxes 10A are arranged on the respective fire bed supports 5 has been described, but without dividing the stoker mechanism 1, Therefore, only the wind box 10 may be divided without dividing the grate support 5. In this case, the grate 2 and the fixed grate 3 may be divided together, and the grate separator 20 may be arranged between each of the divided grate 2 and the fixed grate 3. Alternatively, the grate on the stoker mechanism 1 may be divided into regions, and the air supply amount may be controlled for each region of the grate. <5> In the above embodiment, an example in which the frame 6 is divided in accordance with the division of the grate support 5 has been described. However, the stoker mechanism 1 is not divided, and therefore, the grate support 5 is divided. Instead, only the frame 6 may be divided. In this way, the dust conveyance can be controlled for each of the divided frames 6. For example, the grate 2 and the fixed The grate 3 is divided in the furnace width direction, and a grate separator 20 is disposed between the divided grate 2 and 3.
If the grate is divided into regions and the dust transport is controlled for each of the divided grate regions, and at the same time, if the divided wind box 10A is arranged in correspondence with the divided regions, the air supply amount can be controlled for each of the regions. It is also possible to do. <6> In the above embodiment, an example was shown in which a hydraulic cylinder mechanism was used as the drive unit 7 of the stalker drive mechanism of the present invention, and a link mechanism was used as the power transmission mechanism. It is also possible to use a driving device. For example, an air cylinder mechanism, a direct-acting electric mechanism may be used, and the frame 7 may be reciprocally driven through a known means using a rotary electric mechanism. It is possible.
Further, the power transmission mechanism is not limited to the link mechanism, and it is also possible to use a crank mechanism, a cam mechanism, or the like. Furthermore, it is also possible to provide a drive mechanism combining a rotary drive mechanism that reciprocates and a pinion rack. <7> In the above-described embodiment, an example has been shown in which the grate 2 and the fixed grate 3 constituting the movable grate on the stoker mechanism 1 are formed using the grate pieces 4 arranged side by side. However, the movable grate may be formed by a plurality of integral grate 2 and fixed grate 3 arranged in parallel in a direction orthogonal to the furnace width direction. Each area may be divided and formed by each integral grate 2 and fixed grate 3 provided side by side. <8> In the above embodiment, the grate separator 20 is attached to the grate support 5 by the separator support member 22,
In addition, the example in which the bottom of the grate separator 20 is formed using the separator support member 22 has been described, but the member forming the bottom may be a separate member. 20 may be formed integrally with the bottom. <9> In the above embodiment, on the upper surface of the grate separation body 20, the roof portion 20b having the ridge line and the planar outer surface inclined downward toward the both vertical wall portions 20a is formed. Although an example is shown, the outer surface may be a curved surface,
An upper surface shape having no ridge and bulging upward may be used.

In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part of a garbage incinerator showing a front view of an application example of the present invention.

FIG. 2 is a perspective view of a main part of a stoker mechanism showing an example of a drive mechanism according to the present invention.

FIG. 3 is a longitudinal sectional view of a main part side view of the example shown in FIG. 2;

FIG. 4 is a longitudinal sectional view of a main part front view of the example shown in FIG. 2;

FIG. 5 is a side view of an essential part of a stoker mechanism showing an example of a drive mechanism according to the present invention.

FIG. 6 is a front sectional view of a main part showing an example of a frame support mechanism.

FIG. 7 is a perspective view of a main part of a stoker mechanism showing another example of the drive mechanism according to the present invention.

FIG. 8 is an explanatory perspective view of a conventional stoker mechanism.

[Explanation of symbols]

 2 Grate 6 Frame 9 Drive shaft 9a Bearing 10 Wind box 10A Split wind box

Claims (3)

[Claims] 1. A plurality of grate (2), a frame (6) on which the plurality of grate (2) are placed and supported in a separately positioned state, and arranged in a furnace width direction, and And a drive shaft (9) connected to the frame (6) via a link mechanism. The rotational motion of the drive shaft (9) moves the frame (6) in a direction orthogonal to the furnace width direction. A stoker drive mechanism for a refuse incinerator, wherein the drive shaft (9) is divided and disposed in a furnace width direction. 2. A divided wind box (10A) obtained by dividing a wind box (10) for guiding combustion gas from below the grate (2) in a furnace width direction and forming the divided drive shaft (9). The stoker drive mechanism for a refuse incinerator according to claim 1, wherein the bearing portion (9a) is located outside each of the divided wind boxes (10A). 3. A plurality of grate (2), a frame (6) on which the plurality of grate (2) are placed and supported in a separately positioned state, and arranged in a furnace width direction, and And a drive shaft (9) connected to the frame (6) via a link mechanism. The rotational motion of the drive shaft (9) moves the frame (6) in a direction orthogonal to the furnace width direction. A stalker drive mechanism for a refuse incinerator, wherein a plurality of the drive shafts (9) are arranged in parallel, and each of the plurality of drive shafts (9) is connected to the frame (6) via a separate link mechanism. Stoker drive mechanism of a garbage incinerator.