US1955035A - Grate - Google Patents

Description

A ril 17, 1934. J. s. THOMPSON GRATE Filed Oct.

Patented Apr. 17, 1934 UNITED STATES PATENT OFFICE.

signor, by mesne assig nments, to Waugh Equipment Company, New York, N. Y., a corporation of Maine Application October 4,

12 Claims.

This invention relates to grate bars of the type used in locomotives and boiler furnaces and for other heavy duty purposes. The grate bar of the invention affords especial advantages when employed in locomotives and an embodiment of the invention suitable for such use will be described in detail though it is to be understood that the utility of the new grate bar is not limited to that particular service.

Grate bars now in common use in locomotives have not varied substantially in construction for many years. These' bars are one piece castings of great weight and have a generally rectangular shape with a fiat top surface with a multiplicity of relatively large openings for the passage of air to the fuel being burned thereon. The bars are mounted in a grate frame and the shaker arms of the bars are connected to a common shaker rod so that they can all be rocked in unison. By

' reason of the relatively large amounts of metal which lie between adjacent air openings, the bars are likely to become highly heated in service and frequently become burned or otherwise injured so that they must be replaced. The cost of such replacement is substantial and although only a small part of a bar may be injured, the entire bar weighting as much as 200 lbs. must be scrapped. This operation requires that the fire be dumped, the ash pan removed, the bar be disconnected from the shaker rod, the bar taken out of the grate frame and passed through the fire door, and a new bar placed in position and connected up, after which the ash pan must be replaced. Such operations require several hours time, during which the locomotive is out of service so that the cost of replacement is relatively high by reason of the considerable amount of metal lost, the labor charges involved and the loss of service time of the locomotive.

The present invention is directed to the provision of a grate bar in which the fuel is supported on units which are readily removable and replaceable. These units are of relatively small size weighing as little as 9 or 10 lbs. and the units are supported on a carrier which is provided with trunnions and is mounted in the grate frame in the usual way and connected to the shakerarm. These units are the only part of the bar which comes in contact with the fuel and should one or more units become burned or otherwise injured so as to require replacement, the injured parts may be removed and replaced with only the loss of metal in them. This replacement is a simple operation which does not require changes in the shaker connections or re- 1930, Serial No. 486,349

moval of the ash pan. The units when mounted in place on the carrier are locked against accidental displacement but have a limited freedom of angular movement relative to the carrier which affords certain advantages presently to be described in detail.

In the preferred embodiment of the invention, the carrier is formed of two supporting members which define a lengthwise opening or slot between them. These members are connected at their ends by arms which carry trunnions and the slot has an enlarged entrance'at one or both ends adjacent the trunnion arms. The units are adapted to rest across the supporting members and each unit has a neck which extends through the slot and terminates in an enlarged head of a greater overall width than the width of the slot; Each unit can be placed in position by inserting its head through the slot entrance, after which the unit is slid lengthwise of the carrier with the head underlying the supporting members of the latter. With this arrangement, the units are locked against accidental removal but any unit can be quickly taken off the carrier should occasion arise.

For a better understanding of the invention, 7

reference may be had to the accompanying drawing, in which Fig. 1 is a transverse sectional view through the carrier showing'one of the units in side elevation;

Figs. 2 and 3 are sectional views through the unit on the lines 22 and 3-3, respectively, of Fig. 1;

Fig. 4 is a partial View of the carrier in side elevation illustrating the manner of mounting one of the units thereon; Fig. 5 is a side elevation of a portion of the bar showing a pair of fuel-supporting units mounted in position; and

Fig. .6 is a partial plan view of the bar.

Referring to the drawing, the new grate bar is illustrated as comprising a carrier which includes a pair of supporting members 10 spaced apart to define a lengthwise opening or slot 11. At the ends of the members, the slot is enlarged as indicated at 12 to provide an entrance. The ends of the members are connected by an arm 13' which extends upwardly and is provided with a trunnion 14. Preferably there is an enlarged entrance to the slot at each end of the carrier, and the inner face of the arm within the entrance is undercut, the arm being of less'thickness at this point than at the top adjacent the trunnion. l

Mounted on the carrier are fuel-supporting units, each of which includes a plate 15, the lower walls 16 of which are inclined and converge downwardly, merging into a neck 17 which is provided with an enlarged head 18. These units rest across the supportingmembers, the upper surfaces of which are downwardly and convergently inclined as indicated at 19. The neck 1'7 of each unit passes freely through the slot, while the head underlies the supporting members on either side of the slot.

The unit may be provided with various top constructions but I prefer to employ that disclosed in the co-pending applicationof Buckley, Serial No. 338,352, filed February 8, 1929. According to the Buckley principle, the plate of each unit is provided on each face with a row of spaced lugs 20. These lugs extend downwardly from the top of the plate and are of decreasing size downwardly so that with the plate they define vertical air passages 21 which are of decreasing size upwardly. Extending upwardly from the top of the plate are fuel-supporting projections 22. These projections are preferably arranged in groups of four with a pair of projections of each group overlying a lug and another pair overlying a plate adjacent the lug. The projections of each group are separated by intersecting air channels 23 and 24, the channels 23 communieating with the passages 21 so that air flowing upwardly through the passages can flow horizontally beneath the fuel.

In mounting the units on the carrier, a unit is placed adjacent the arm 13 and moved downwardly at a slight inclination. as illustrated at Fig. 4 so that its head 18 passes through the entrance 12. This movement of the unit is facilitated by making the lugs 20:: at the middle of the unit of less thickness than the remaining lugs. The thinner lugs permit the use of an entrance opening which is narrower in a direction lengthwise of the carrier and require less tilting of the unit in order to mount it on the carrier, as illustrated in Fig. 4. When the head has passed below the lower edges of the supporting members 10, the unit is swung to upright positionand then slid lengthwise of the carrier to a position such as that indicated at 25, Fig. 5. The units are placed successively on the carrier until the latter is provided with its full complement and the end unit in the series when in contact with the inner face of the arm 13 lies in the position with the head fully underlying the edges of the members 10. The end unit is thus positively locked in position. By placing the entrance or point of unlocking .outside or beyond that portion 01' zone of the carrier on which the units are supported, accidental 'dislodgement'of the units from the carrier is prevented.

Ordinarily the units space themselves along the carrier with the end unit in contact with the portions 26 of the trunnion arm 13. When in this position-the head 18' of the end unit lies beneath the supporting members at a considerable distance from the lower end of the entrance andthe end unit cannot fall from the carrier when the latter is tilted. Removal of the unit requires that it be tilted and for this purpose, the units must be crowded together on the carrier until sufficient space is provided to permit the end unit to tilt; The normal distribution of the units on the carrier, however, is such as to prevent the end unit from tilting to the degree necessary to permit it to be thrown free accidentally. The units are spaced apart along the bar.

by spacing lugs 27 which are formed as extensions from certain of the lugs 20.

By making the neck of each unit a loose fit in the slot in the carrier and so proportioning the length of the neck that the head 18 at the end thereof lies free of the under surface of the supporting members 10, each unit may move through a substantial are relative to the carrier about an axis lengthwise of the latter. In locomotive service in which the bars are subjected to frequent shocks and jars incident to road travel, the units move relative to the carrier to an extent such that the bar has a substantial self-cleaning action.

Also, this limited freedom of movement of the units and carrier facilitates the shaking operation. In the ordinary grate, any movement of the shaker handle produces a similar movement of all the grate bars. Consequently, the fireman must apply full force to the handle at the start of the shaking operation in order to effect any shaking. Shaking of such a grate is so difficult that power shaking devices are frequently required. With the new bar, the fireman swings the shaker handle connected by a shaker rod to the several shaker arms 28 of the carrier members, and the carriers begin to tilt but in the initial part of such movement, the fuel-supporting units are not locked to the carrier and thus remain stationary under the weight of the fuel carried thereon. When the rocking of the carriers continues to a further extent, the carriers become locked to the units and further movement of the carriers results in movements of the units thereon. However, by reason of the initial move ment of the carriers independent of the units, the fireman may apply substantial force to the shaker handle which results in giving the carriers considerable momentum and this results in the application of a sudden shock to each of the units which serves to break up the fuel bed and thus permit further shaking without difficulty.

In the construction illustrated, the shaker rod 28 is formed as a downward extension from the carrier and is connected to both supporting members thereof. Also, if desired to strengthen the carrier, the supporting members may be connected at suitable intervals by cross pieces similar to the upper part of the shaker arm and of such shape as not to interfere with the movement of the units lengthwise of the carrier.

What I claim is:

l. A grate bar which comprises a carrier formed with a lengthwise slot open at the top and bottom of the carrier and having a continuously open entrance of greater width than said slot, and a plurality of fuel-supporting units mounted on the carrier and each having an extension projecting through the slot and portions underlying the carrier at opposite sides of the slot, said extension normally lying entirely out of contact with the walls of the slot and being of an overall width less than the width of said entrance, and said units and carrier having a limited freedom of relative angular movement on an axis parallel to the longitudinal axis of the carrier, said entrance lying outside the zone of support provided by the carrier to the units.

2. A grate bar which comprises a carrier having a lengthwise slot and an enlarged continuously open entrance communicating with said slot, and a plurality of fuel-supporting units mounted on the carrier, each unit having a neck passing through said slot and normally out of contact with the side walls thereof and a head at the end of the neck underlying the carrier at either side of the slot and normally out of contact with the carrier, said head having a less overall width than the entrance and said units and carrier having a limited freedom of relative angular movement on an axis parallel to the longitudinal axis of the carrier, said entrance lying beyond that portion of the carrier which provides support to the units.

3. A grate bar which comprises a carrier having a lengthwise opening and an enlarged continuously open entrance thereto, a plurality of fuelsupporting units mounted on the carrier, each unit having a neck entering said opening and normally out of contact with the walls thereof, and locking means on each unit preventing removal of the unit from the carrier except at said entrance, said locking means being normally out of contact with said carrier permitting said unit and carrier a limited freedom of angular movement on an axis lengthwise of said carrier, said entrance lying outside the zone of support afforded by the carrier to the units.

4. A grate bar which comprises a carrier having a slot therein, a plurality of fuel-supporting units mounted on the carrier above the slot, each unit having a neck entering the slot and normally out of contact with the walls thereof, said units and carrier having a limited freedom of relative angular movement on an axis lengthwise of the carrier, and cooperating parts on the units and carrier preventing free displacement of the units from the carrier, said parts on the unit being normally out of contact with the carrier and engageable therewith to limit said angular movement and said slot being formed with an enlarged portion at at least one end thereof to provide a continuously open entrance sufliciently large to permit passage of said parts of said units, said entrance lying outside the zone of support afforded by the carrier to the units.

5. A grate bar which comprises a carrier having a lengthwise slot and provided with trunnions at its ends, and a plurality of fuel-supporting units mounted on the carrier and extending across the slot, each unit having a neck entering the slot and normally out of contact with the walls thereof, said neck terminating in a head of greater width than the slot, said slot, neck and head being so proportioned that the unit and carrier have a limited freedom of relative angular movement in either direction on the axis lengthwise of the carrier, said neck and head binding against parts of said carrier to limit said movement and said slot having an enlarged entrance through which said head may freely pass, said entrance lying outside the zone of support provided by the carrier to the units.

6. A grate bar which comprises a carrier including a pair of spaced supporting members and trunnion arms joining the ends of said members, said members defining a slot having an enlarged entrance, and a plurality of fuel-supporting units mounted to rest across said members, each unit having a neck freely receivable in said slot and normally out of contact with the walls thereof and a head at the end of said neck of greater width than the width of said slot, said head being movable through said entrance and normally underlying but out of contact with said members when said unit is in place thereon, said entrance being formed in part in one of said arms.

'7. A grate bar which comprises a carrier which includes a pair of spaced supporting members, arms joining the ends of said members, and trunnions projecting from said arms, said members defining a slot having an enlarged opening at least one end adjacent one of said arms, said arm being cut away to provide part of said entrance, a plurality of fuel-supporting units mounted across said members, each unit having a neck entering said slot and terminating in a head of greater overall width than the slot at its top, said head being of less width than said entrance.

8. A grate bar which comprises a carrier having a lengthwise opening, and a plurality of fuelsupporting units on said carrier across said opening, each unit having a part extending through said opening and underlying said carrier to lock said unit and carrier together, said opening being provided with an entrance continuously open and permitting free removal of the units from the carrier, said entrance lying outside the zone of support provided by the carrier to the units.

9. A grate bar which comprises a carrier having a lengthwise opening, and a plurality of fuelsupporting units on said carrier across said opening, each unit having a part entering said opening and underlying a part of said carrier, said part lying normally out of contact with the carrier but engageable therewith on relative angular movement of the unit and carrier to lock said unit and carrier together, said opening having an entrance continuously open and permitting free removal of the units from the carrier, said entrance lying at one end of and beyond the zone of support provided by the carrier to the units.

10. A grate bar which comprises a carrier having a lengthwise opening, and a plurality of fuelsupporting units on said carrier across said opening, each unit having a part extending through said opening and underlying said carrier to lock said unit and carrier together, said opening having a continuously open entrance through which the end unit of the group may be removed, this entrance lying beyond that portion of the carrier upon which said end unit is normally supported.

11. A grate bar which comprises a carrier hav ing a lengthwise slot and upwardly extending arms at its ends, and a plurality of fuel-supporting units on'said carrier across said slot, each unit having a part entering said slot and underlying said carrier to lock said unit and carrier together, said slot having an entrance at one end permitting free passage of said parts of each unit said entrance lying adjacent one of said arms and i being formed in part in said arm.

12. In a grate bar, the combination of a carrier comprising a pair of supporting members with a slot between them extending lengthwise of the bar, and upstanding arms at the ends of the members, said arms carrying trunnions and said slot being enlarged at at least one end to provide an entrance formed also in part in said arm, and a group of fuel-supporting units resting on said members and having extensions received i in said slot, said extensions having portions with an overall width greater than the width of the slot and less than the width of said entrance, said arm having a portion on its inner face normally engaging the end unit in said group and main- 1;

taining said unit in a position in which its extensions lie spaced from said entrance.

JAMES S. THOMPSON.

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