US1201584A - Engine safety control mechanism. - Google Patents

Description

J. C. F. HINDES.

ENGINE SAFETY CONTROL MECHANISM. APPLICATION FILED MAY 23. 1916.

Patented Oct. 17, 1916.

3 SHEETSSHEET 1- J. C. F. HINDES.

ENGINE SAFETY CONTROLMECHANISM.

APPLICATION FILED MAY 23. 1916.

1,201,584. Patented Oct. 17,1916.

3 SHEETS-SHEET 2- J. C. F. HINDES.

ENGINE SAFETY CONTROL MECHANISM.

APPLICATION man MAY 23, I916.

Patented Oct. 17, 1916.

3 SHEETS'SHEET 3.

JOHN G. r. HINDES, or ROCKFORD, ILLINOIS.

ENGINE SAFETY CONTROL MECHANISM.

Specification of Letters Patent.

Patented Oct. 17, 1916.

Application filed May 23, 1916. Serial No. 99,442.

1 all whom it may concern:

Be it known that 1, JOHN C. F. HINDES, a citizen of the United States, residing at Rockford, in the county of Winnebago and State of lllinois, have invented certain new and useful Improvements in Engine Safety Control Mechanism, of which the following is a specification.

This invention relates in general to automatic cut-01f steam engines, especially of the Corliss type, and has more particular reference to the governor control of the admission valves. In engines of this character, it sometimes happens that, due to improper governor action, the engine will race so to cause damage before the operator can stop the engine by means of the manual control. Such an occurrence may be traced to breaking of the belt drive connection between the engine shaft and governor and to defective operation of the governor itself.

The primary object of my invention is to provide means for preventing racing of the engine in case the governor does not properly perform its function.

To this end, my invention contemplates the provision of novel means adapted to be actuated by breaking of the governor drive connection to thereupon stop the engine, which means preferably operates in part through the connecting links between the governor and admission valves of the engine and does not interfere with normal opera tion of the governor. I have also provided means for stopping the engine in case racingv of the same is caused by defective operation of the governor, comprising a secondary governor, preferably cooperatmg wlth the manual valve control mechanism for operating the same to stop the engine when the speed thereof exceeds a predetermined maximum and is not checked by either the primary governor or the auxiliary stop control mentioned.

A still further object is the provision of means adapted to be attached to any conventional type of automatic cut-01f steam engine for automatically stopping the-engine when its governor does not function to check speeding the engine beyond a predetermined maximum.

Referring to the drawings: Figure 1 is a side elevational view of a portion of a steam engine, showing my improvements embodied therein; Fig. 2 is a plan view of the mechanism shown in Fig. 1; Fig. .3 is an enlarged fragmentary view of the auxillary cut-off mechanism showing in dotted lines the manner in which'the same is oper ated; Fig. 1 is a detail edge view of the cable tension device shown at the left of Fig. 3; Fig. 5 is a detail plan sectional view taken substantially on the line 55 of Fig. 3; Fig. (3 is a fragmentary view of the secondary lever mechanism; and Fig. 7 is a detail sectional view taken on the line 77 of Fig. 6.

I have illustrated my improvements in connection with an automatic cut-off steam engine of the Corliss type, having-shown in the drawings only such portions of the en gine as are necessary for a clear understanding of the invention. The parts shown consist of a cross-head guide-bar frame 8 of conventional design, a piston rod 9, a pitman 11, and crank shaft 12. The admission valve cam arms (not shown) are adapted to be operated by connecting links 13 and 141 pivotally attached to the opposite ends of a rocker arm 15 that is adapted to be operated by a governor. In the present instance, the rocker arm 15 is fixedly secured intermediate its ends to a sleeve 22 loosely mounted on a stud fixed to the governor column 17 which is mounted on the frame 8. A conventional type of fly-ball governor 18 mounted on a spindle in the column 17 is connected to the rocker arm 15 through the intermediary of a link 19 and an arm 21 formed integral with the sleeve 22. The connection between the link 19 and arm 21 is designed to cause up and down movement of the link to be imparted to the arm 21, but permits the said arm 21 to rock upwardly independently of the said link. In the present instance the lower end of the link 19 is equipped with a pin 23 engaged in an arcuate slot 24 in the arm 21, the outer end of said arm being weighted sufficiently to maintain the arm in lowermost position limited by abutment of the pin 23 against the upper end of the slot. A driving connection between the governor spindle and crank shaft is established by means of a belt 25 run over a pulley 26 on the .crank shaft 12 and a pulley 27 mounted on a shaft 28 that is geared to the governor spindle. During operation the, governor maintains a uniform engine speed through the intermediary of connections 13, 14, 15, 19 and 21, it being'obvious that in case the speed of the engine exceeds a predetermined maximum the ball-governor will raise the link 19 and rock the arm 15 in a counterclockwise direction, viewing Fig. 1, which will move the admission valves toward closed position and that a decrease in speed below a certain rate will cause reverse action by the governor.

Manually operable means is provided for moving the rock lever 15 in a direction to close the admission valves and stop the engine. This means may comprise a cable 29 extending from a convenient operating point over a sheave 31, through a pair of suitable spring tension pulleys 32 supported from the governor column and being connectedto a link 33 which in turn is pivotally connected to the upper end of a lever 34 fixedly connected to the sleeve 22. The tension pulleys maintain the cable taut and allow a certain amount of slack cable adjacent to its connection with the link 33 so as not to interfere with the governor action. By pulling on the cable the arm 34 will be rocked in a counterclockwise direction as indicated by dotted lines 35, Fig. 3., whereby to move the admission valves in a closing direction. This rocking movement of the arm 34 and consequently of the parts connected to the sleeve 22 is limited by abutment of the lug 36 on said arm against a lug 37 on a collar adjustably mounted on the stud 16, as shown in Fig. 5. Thus the operator may at any time stop the engine by pulling on the cable 29.

Coming now to the means for stopping the engine in case the driving connection between the engine and governor should be broken which would occur if the belt 25 broke or ran off of its pulley, I have provided means normally maintained out of operation by the belt 25 when the same is in proper running order but adapted to be put into operation by falling of the belt, so as to cause the admission valve mechanism to be moved in a closing direction. This means consists of an arm 33 pivotally mounted at 35' on the frame 8 and equipped at its outer end with a pulley 41 resting and running idly on the top of the upper lead of the belt 25, the arm 38 being so connected to the sleeve 22 that it will not interfere with the action of the governor 18 but will actuate said sleeve in a valve closing direction in case the arm 38 should fall. Since the arm 38 is connected to the sleeve 22 through the intermediary of links 42 and has a slot and pin connection with the arm 43 which is fixed to the sleeve 22, the said arm 38 does not, while maintained in a horizontal position between the belt 25, interfere with the action of the governor 18. Should the belt 25 break, however, or run off its pulleys, the arm 38 would drop to the position indicated in dotted lines in Fig. 3, and thereby close the admission valves and stop the engine. It will thus be seen that if the governor 18 should be stopped by breaking of the driving connection thereto the engine would be automatically stopped.

The automatic control of the engine is sometimes interfered with by reason other than breaking of the governor driving connection mentioned another cause being defective operation or the governor 18 such as will allow the speed of the engine to exceed the desired maximum. In order to safeguard against such an occurrence 1 have provided a secondary governor connected with the admission valve mechanism, which governor is regulated to stop the engine when the speed thereof becomes slightly greater than the predetermined maximum allowed by the primary governor 18. This secondary governor 44 preferably of the same type as the primary governor but somewhat smaller is mounted on a column 45 011 the base 8 and adapted to be driven from the crank shaft 12 by a belt 46. The secondary governor operates through the cable 29 to stop the engine, the operation being the same as though the operator pulled on the said cable. The means whereby this result is effected consists of link 47 connect ing the slidable element of the governor 44 to a yoked lever 48 pivotally mounted on the column 45 and providing a rest '49 at its opposite end to receive an end of a lever 51 pivotally mounted on a bracket 52 in turn mounted on the standard, the lever 51 con stituting one element of a trip device adapted to be released by action of the governor when the engine speed reaches a predetermined maximum. The other element 53 of the trip device, pivotally mounted on the bracket and having a notch 54 in its lower end in which the end 55 of the lever 51 engages, is detachably connected to a cable 56 run over a sheave 57 to a weight 58. This weight holds the trip device engaged, that is, holds the element 53 in engagement with the element 55 in such manner as to hold the latter element in set position, permitting the yoked lever 48 to be rocked downwardly with respect to the lever 51. Should, however, the lever 48 be raised by the governor 44 when a predetermined maximum speed is reached, the lever 51 will be rocked and released from the lever 53, allowing the weight 58 to fall. length of the links 47 the point in engine speed at which the said trip will be released may be regulated with respect to the maximum speed at which the governor 18 is designed to move the admission valves in a closing direction. Thus the secondary governor mechanism may be set to become effective when a maximum engine speed is reached slightly higher than the maximum running speed allowed by the primary gov- By adjusting the nut 59 and the ernor. through means of the short cable connection 61 between the cables 56 and 29 pull the latter and close the admission valves the same as though the operator had pulled on said cable.

In the operation of a steam engine equipped with my improvements it will be understood that the primary governor is adjusted to maintain the engine at a normal running speed and that the secondary governor is set to stop the engine should the speed thereof exceed a maximum at which the primary governor should, if it were properly functioning, slow down the engine. Thus the primary governor is designed to serve the same purpose as any ordinary governor, that is, to maintain a normal running speed. Should the drive of this governor be broken by dropping of its drive belt 25 the engine will be stopped by falling of the arm 38, which operates the cam links 13 and 14 to close the admission valves as described above. The engine may also be stopped at will by pulling on the cable 29 and through -means of this cable the engine may also be stopped by the action of the secondary governor when the primary governor, even though its driving connection is intact, becomes defective and permits the engine to race. It will be noted that all the devices employed for moving the admission valves in a closing direction lead to the rocker arm 15 that connects by means of links 1314 directly to the admission valve cams, and that the arrangement is such as to not interfere with the'normal operation of the primary governor. It will also be noted that the several connections are advantageously arranged so that each valve operating de vice does not have an entirely independent connection to the valve links but they all operate in part through common operating mediums. This feature is made possible by a construction including certain loose connections such as the slot 24, the slot connection between the links 42, the loose link connection 33 and the flexible cable connection 61.

I claim:

1. The combination with an engine and governor controlled cut-off mechanism therefor, of a rocker arm connected with the valves of said cut-0E mechanism, a connection between said rocker arm and governor including a slot and pin, and means whereby the governor will operate said rocker arm to maintain the engine at a normal running speed and whereby said rocker arm may be moved in a valve closing direction independ ently of the governor movement, and a secondary governor so connected with said rocker arm as to permit the primary governor to normally control the engine and to move the said rocker arm in a valve closing When the weight 48 falls at will,

therefor including a rocker arm for operating the valve mechanism, a one-way con nection. between the rocker arm and governor, and means operating independently of the governor and connected to therocker arm in such manner as not to interfere with the operation of said governor, for operating the rocker arm in a valve closing direction when the speed of the engine exceeds a predetermined maximum and is not checked by the governor.

3. The combination of an engine, a governor controlled cut-off valve mechanism therefor including a rocker arm for operating the valve mechanism, means constantly urging the rocker arm in a valve opening direction, a one-way connection between the rocker arm and governor operating against the influence of saidmeans, said one-way connection enabling the rocker arm to be moved in a valve closing direction independently of the governor movement, a second governor, and a connection between this governor and the rocker arm permitting said arm to be operated by the first governor without disturbing the second governor, this connection being so arranged and the second governor so set as to operate the rocker arm in a valve closing direction when the speed of the engine exceeds. a predetermined maximum and is not checked by the governor.

4. The combination with an engine and cut-oil valve mechanism therefor, of a governor, a rocker arm connected to the valve mechanism for operating the same, a connection between the governor and rocker arm including a slot and pin connection, means holding the pin engaged with one end of the slot whereby the governor is normally in operative connection with the rocker arm, a second governor adapted to be rendered 0perative when the speed of the engine exceeds a predetermined maximum, a connection between the second governor and said rocker arm including a lost motion portion where by the first governor may be operated inde pendently of the second governor and whereby the latter may operate the valve mechanism in a closing direction when the first governor does not function properly.

5. The combination with an engine and valve cutoff mechanism therefor, of a governor, a rocker arm connected with the valve mechanism for operating the same, a one- 'way connection between the governor and slack in said cable so that the samewill not disturb movements of the rocker arm under the influence of the governor, a second governor, and means connecting the same and the cable and constructed for operating the cable to move the rocker arm in a valve closing direction when the first governor does not function properly.

6. The combination of an engine, a governor controlled cut-off valve mechanism therefore including a rocker arm-for operating the valve mechanism, a oneway connection between the rocker arm and governor enabling the rocker arm to be moved in a valve-closing direction independently of the operation of the governor, a belt drive for the governor, a devlce engaglng the belt and maintained inoperative thereby but rendered operative by the action of the belt running off its pulleys or breaking, and a connection directly between said device and rocker arm including a lost motion connection allowing the rocker arm to be operated by the governor independently of said device and whereby said device when rendered operative will move said rocker arm in a valve-closing direction.

JOHN G. F. HINDES.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C.

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