US2275102A - Telltale hole opener for staybolts - Google Patents

Description

March 3, 1942. E. s. Fn'z slMMoNs 2,275,102

TELLTLE HOLE OPENER FOR STAYBLTS A 2 Sheets-Sheet l Filed Aug. 24, 1940 NN NNI mm. NN @NWN March 3, 1942. E s, FlTZ slMMQNs 2,275,102

TELLTALE HOLE OPENR FOR 'STAYBOLTS Filed Aug. 24, 1940 2 Sheets--Sldeecl 2 INVENTOR ami? /mlg MM Patented Mar. 3, 1942 TELLTALE HOLE OPENER FOR STAYBOLTS Edward S. Fitz Simmons, Library, Pa., assignor to Flannery Bolt Company, Bridgeville, Pa., a

corporation of Delaware ApplicationAugust 24, 1940, Serial No. 354,052

1 Claim.

This invention relates to a device for cleaning out the holes of tell-tale staybolts prior to testing during the inspection of boilers in which the bolts are installed. i

Staybolts with tell-tale holes therethrough are well-known and have been widely used for many years in the construction of locomotive boilers. When boilers constructed with such staybolts are to be inspected, it is necessary to make sure ythat the tell-tale holes are open and free from obstruction throughout their entire length. The clogging of the tell-tale holesin the staybolts by the accumulation of material therein is almost impossible to prevent under some operating conditions, despite the insertion of porous plugs in the open ends of the holes which is customary. The accumulated material, furthermore, may be of such character that it is very difficult to remove. Sometimes the accumulations have a Ilinty hardness such that tools heretofore available will not suflice to loosen them.

I have invented a device for clearing the telltale holes of staybolts, which is capable of removing even the hardest deposit since it utilizes both impact or percussion and cutting edges for reducing the accumulations to the form in which they may be readily removed. In a preferred embodiment, the invention comprises a pneumatic gun having a piston reciprocable therein adapted to serve as a hammer. A drill, of such size as to be insertable in the tell-tale hole of a staybolt, has a head rotatably receivedin the end of the gun in such position as to be subject to the impact of the reciprocating piston. The drill is yieldably held in position in the gun and is provided with means whereby it may be manually rotated relative to the gun. The drill has a passage extending longitudinally throughout the length thereof and the piston also has a central bore whereby the motive fluid, usually compressed air, is delivered to the end of the drill to blow out particles of material accumulated in the tell-tale hole, as it is granulated by the combined effect of the hammer blows applied to the drill and the engagement of its cutting edges with such accumulations.

The accompanying drawings illustrating a preferred embodiment of the invention, will be referred to during the following detailed description and explanation. In the drawings:

Fig. 1 is a longitudinal, central, sectional view illustrating the invention, with parts in elevation;

Fig. 2 is a view similar to Fig. 1 showing parts in alternative positions;

Fig. 3 is a view partly insecton along the plane of line III--III of Fig. 1 and partly in elevation;

Fig. 4 is an end view of the drill; and

Fig. 5 is a central, longitudinal section through a tell-tale hole staybolt installed in a boiler, illustrating the use of the invention in removing the material which accumulates therein during normal operation. y

Referring now in detail to the drawings, the device of my invention comprises a gun I0 and a drill I I. As to most of its features, the gun I0 is of known construction and will, therefore, be described rather generally for the most part, and

the detailed description confined to the novel features. The gun I0 includes a handle I2 and a barrel I3. The barrel I3 is threaded into a bore |4 in one end of the handle and is provided with a valve case I5 and a plug IB closing the rear end of the valve case. A dowel pin |6a maintains the valve case I5 and the plug I6 in the proper angular relation relative to the barrel I3.

The barrel I3 has a longitudinal bore I 'I therethrough in which a piston I8 is reciprocable. The bore II is slightly enlarged at each end as indicated at I9 and 20. A restricted passage 2| provides communication between the bore I4 and the enlargement I9. A passage 22 extends from the bore I4 longitudinally of the handle I2 and communicates with a supply of motive fluid such as compressed air, by a connection 23. A throttle valve 24 actuated by a push button 25 controls the supply `of air to the passage 22.

The valve case I5 has a bore 26` in which a sleeve valve 2'I is reciprocable. As shown in the drawings, the valve 2'I has a longitudinal bore 28 through which the piston I8 reciprocates. The bore 28 has a substantially central enlargement 28a and to the rear thereof an enlargement 29,.

is provided at the rear end ofbore 32. The valve case I5 has a passage 30 formed therein which communicates with a recess 30a in the forward face of the plug I 6. A passage 3| extends forwardly from the bore I4 into the valve case I5 and plug I8.

As shown in Fig. 1, the rear end of the Valve 2l reciprocates in a bore 32 in the plug I6. An annular groove or enlargement 33 is formed in the bore 32 and is in communication, through passages 34, with the bore I4.

l The valve 21 is turned down slightly adjacent the rear face of the central shoulder thereof forming a groove 34a. The groove 34a connects the recess30a to a passage 3Ia intersecting passage 3I, when the valve is in its rea-r position as shown in Fig. 1. A

tween opposite ends of the bore I1. The piston I8 executes a rapid forward traverse movement which is unchecked, so that it is able to deliver a heavy blow. The forward stroke of the piston is accompanied by a movement of the sleeve valveV 21 whereby air under reduced pressure is supplied through the passage 33. This causes the piston to execute a relatively slow return stroke which is checked by the entrapment of air in the rear end of the bore I1 whereby the piston is brought gradually to rest as the entrapped air is discharged through the restricted passage 2 I. A more detailed description of the operation of the gun follows.

Assuming the moving parts to occupy the relative positions illustrated in Fig. 1, i. e., the piston I8 near the forward end of the bore I1 and the valve 21 in its rearmost position, air under pressure is admitted to the passage 22 and bore I4 when the valve 24 is opened by actuating the push button 25. From the bore I4, air flows through the passage 3|, the passage 3Ia, around the groove 34a, through the recess 39a, passages 3B and 35 to the forward end of the bore I1. The piston I8 is forced rearwardly as the pressure builds up in the forward end of the bore' I1.

After traversing a portion of its rearward stroke, the piston I8 uncovers a radial port 35h in the barrel I3. A longitudinal passage 35a in the barrel intersects the port 35h and communicates with a passage 36o in the valve case I5. A restricted port 33C connects the passage 3611 to the passage 3|. When the port 35h is uncovered, air under pressure is admitted through the passages just described to the bore 23 and bears on the forward face of the simple flange of the valve to hold it in rear position.

As the piston I8 continues to travel rearwardly, the air displaced ahead of it flows to the atmosphere through the exhaust passage 35. This passage, however, is shortly covered by the piston and the pressureof the air trapped in the rear Vend of 'the bore I1 thereupon becomes effective upon the rear annular surface of the valve adjacent the enlargement 29 tending to move it forward as soon as the trailing end of the piston uncovers the passage 35, relieving the pressure behind the piston and ahead of the central shoulder of the valve. As soon as the valve 21 starts forward, air under pressure bears on the rear face of the central shoulder thereof, being supplied through the passages 3| and 3 Ia.

When the valve has moved to the forward position shown in Fig. 2, it closes the exhaust passage 35. The final portion of the rearward stroke of the piston is cushioned by the air trapped in the bore I1, as already described. As a matter of fact, the air in the rear end of the bore I1 is at working pressure because of the connection between the bore and the chamber I4 which is established through the passages 2 I.

With the valve in the forward position, the supply of air under working pressure to the forward end of the bore I1 is cut olf by the blocking of the passage 3Ia. The forward end of the bore I1, furthermore, is open to the atmosphere through passages 36 and 30, the recess 30a, the groove 34a and the radial exhaust passage 35a. As previously stated, air under working pressure is effective continuously through the restricted connection 2| to force the piston forward. When the piston on its forward stroke has covered the radial port 35h, the air previously flowing through a restricted port 36a is diverted to the valve case and acts upon the forward face of the central shoulder of the valve causing it to return to its rearmost position. This cuts off the flow of air into the bore I1 through the passages 34 and connects the interior of the bore I1 to the atmosphere through the passage 35. The piston I8 continues to move toward the forward end of the bore by virtue of its momentum and delivers a sharp blow to the drill head, to be described in detail shortly. Simultaneously, air under working pressure is admitted to the forward end of the bore I1 as previously described.

The drill II has a head 31, the extreme end 38 of which is turned down to fit rotatably in a bore 39 formed in the forward end of the barrel I3. The head 31 is yieldably held in the position shown in Fig. l by a coil spring 30, the outer end of which is contracted around the head and the inner end of which is threaded on the end of the barrel I3 which has a helical groove II providing threads to receive the turns of the spring 130. With the head 31 in the position shown, the inner end 38 thereof is in position to receive the impact of the piston I8 when it reaches the end of its forward stroke causing slight relative movement axially between the barrel I3 and the drill II.

The forward end of the head 31 is preferably provided with flats 42. A lever-type wrench 43 has an opening corresponding in shape with the section of the forward end of the head whereby the drill I I may readily be turned manually without shifting the handle I2 of the gun.

The shank of the drill II indicated at M is preferably of tool steel and is shaped at its extreme end to provide cutting edges d5. The drill shank may conveniently be brazed to the head 31. The latter and the piston I8 are preferably of steel and are specially treated to render them very hard and resistant to deformation by impact.

y The piston I8 is provided with a central bore or passage 41. The drill II is provided withl a similar bore 48 extending through the entire length thereof from the extreme rear end 38 through the head 31 and the shank M to the working end whereon the cutting edges 45 are formed. The function of these passages will be explained shortly.

The manner of using the tool described above in cleaning out the tell-tale holes of staybolts will doubtless be readily apparent but will be briefly described nevertheless, with reference to Fig. 5. As there shown, a staybolt 43 has al telltale hole 46a extending thereinto. The bolt has an enlarged head 49 engaging a bearing seat 39a welded to the outer boiler sheet 5I). A plug 5| is threaded into the end of the bearing seat. The other end of the bolt is threaded into the inner boiler sheet or fire-box end 52 and is upset as at 53.

In normal operation of a boiler, an accumulation of material such as indicated at 5d tends to build up in the tell-tale hole 43a and this accumulation must be removed before the boiler may be tested during inspection. To accomplish this removal, the device shown in Fig. l is so manipulated as to insert the drill II into the open end of the tell-tale hole. The operator then actuates the push button and simultaneously applies pressure to handle I2 to force the cutting edges 45 of the drill into engagement with the accumulated material 54. The resulting reciprocation of the piston I8 delivers heavy blows in rapid succession to the rear end 38 of the head 31 of the drill I I. While forcing the drill into a tell-tale hole with his right hand, the operator manipulates the wrench 43 with his left hand to turn the drill back and forth through a considerable angle as indicated by the chainlines in Fig. 3. This, of course, has the effect of rotating the drill II relative to the gun It. The rapid blows on the drill combined with the cutting action of the edges 45 thereof effects a rapid granulation of the Vaccumulated material 54. The particles of accumulated material are forced out of the tell-tale hole beyond the working end of the drill by air flowing through the bore 41 in the piston I8 and through the bore 48 through the drill I I. The Velocity under which the air flows from the working end of the drill varies from a minimum when the piston is in its rearmost position as shown in Fig. 2, to a maximum just before the piston engages the rear end 38 of the drill head 31. At such time, substantially full line pressure is effective on the rear face of.

the piston and, since the passa- ges 41 and 48 are in alinement, air ows out through the end of the drill at high velocity. Air is thus delivered from the end of the drill in a series of puis or jets of maximum velocity in synchronism With the reciprocation of the piston, and during the shifting of the valve air flows in a continuous manner from the pressure supply through passage 2|, thereby providing a particularly effective blowing out of the particles of accumulated material loosened by the drill. The flow of air through the drill continues during the return stroke of the piston by virtue of the working pressure in the forward end of the bore I1.

It will be apparent from the foregoing description and explanation that the invention provides a device for opening the tell-tale holes of staybolts, which is characterized by numerous advantages. In the rst place, the construction of the device is relatively simple and inexpensive. Its operation, furthermore, is based on tried principles so that maintenance problems are reduced to a minimum. The mass of the reciproeating drill is relatively small. The inertia oi the drill is correspondingly reduced and the drill is capable of reciprocating at high speed. The ability to turn the drill relative to the gun is a great convenience to the operator as it is desirable to turn the drill yet it is not always convenient to turn the gun. The lever 43 is so made that it can readily be manipulated by the operator with his left hand, without danger of injury thereto by the vibration, since the wrench fits loosely on the drill head permitting axial movement of the latter relative thereto.

By leading the air for blowing out the chips through the piston and drill, I avoid any lateral connections to the latter which would be subject to breaking off because of the rapid reciprocation of the drill. The eiectiveness of the successive puffs or jets of air in blowing out the detached particles of accumulated material has already been mentioned.

Although I have illustrated and described but a preferred embodiment of the invention, it will be apparent that changes in the construction and arrangement disclosed herein may be made without departing from the spirit of the invention or the scope of the appended claim. The piston I8, for example, may be solid instead of having the bore 41 therethrough. In that case, air ows through the drill passage 48 only during the return stroke of the piston when substantially full line pressure exists in the forward end of the bore I1. This produces an even morev pronounced effect of separate pus or jets of air than that obtained with a piston having a longitudinal bore therethrough.

I claim:

A device for removing accumulations from the tell-tale hole of a staybolt, comprising a barrel having a bore therethrough, a piston reciprocable in said bore, a valve controlling the admission of fluid under pressure to opposite ends of said bore from a pressure supply, whereby to reciprocate said piston, a drill in the end of said barrel so as to be subject to impact blows by said piston, and alined, restricted axial passages through said piston and drill, there being a restricted port in direct communication with the rear end of the bore and the pressure supply, whereby the passage through the drill is continuously open to the pressure supply during the shifting of the valve to reverse the movement of the piston.

EDWARD S. FI'IIZ SIMMONS.

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