US2220702A - Safety device - Google Patents

Description

c. E. BLANK SAFETY DEVICE Nov. 5, 1940.

Filed'Oot'. 20, 1938 2 Sheets-Sheet l INVENTOR` Ulan/lef L. Blank Hl s' ATTORNEY Patented Nov. -A, 1940 UNITED .sr-Ares SAFETY DEVICE Charles E. Blank, .Painted Post, Y., assi-gnor'to Ingersoll-Rand Company, Jersey City, N. Lia Y corporation of New Jersey Application october-20, mensual-No.' 236,018

10 Claims. .(Cl. Z30-.30).

This 'invention relates to a safety vdevice `for engine driven compressors and more particularlyit relates ltoa 'device adaptedto regulate theamount of fluidmedium delivered to the engine and to actas a safety cut-'oir to prevent thedelivery'of Aany power medium'to the engine under certain conditions.

The presentdevice is adapted for 'usewith a compressor kunit 'which vnormally consists of 'a fluid compressor driven by an engine actuated by a power medium preferably steam. The de-` vice Inay 4be actuated by'aluid, such as oil from the vengine lubricating system supplied thereto under pressure 'by veither Vthe lubricating pump l5`or Aa'separateoil pump. The apparatus may be employed to maintain the-speed ofthe compressor unit constant regardless of the lfluctuations of pressure in the powermedium actuating the engine or of the pressure of the fluid in the 20. receiver tankoilthe compressor.

Furthermore, the device is so arranged that should the oil pressure decrease for any reason, the steam supply to the engine is cut off to stop the operation-oi the unit until any defects may be ascertained and remedied.

In such an installation, two separate valves would V'ordinarily be furnished, one valve -being employed to throttle the steam supply in accordance with the load demand and another valve to act vindependently of the iirst valve to stop the flow of -powermedium to theengine. Such 'an arrangement is subject `to many disadvantages. v

It Vis, accordingly, an object Aof the present .invention to' provide a device wherein the throttle valve and the cut-off valve are combined in one 'unit and inter-related in operation. n

It isanother object-to provide a device wherein the power supply tothe lcompressor"unit lmay be 40 ycut offto'sto-p Loperation of the unit. I.

A Afurther objectistofprovide a device lwherein the power medium may bethrottled before :be-

ing supplied to the .engine savewhenthe power medium supply has been cut oi.

Still anotherobjiectisftoprovide`a simplified.

power mediumthrottl'e and cut-oliv device.

fTheseand'other'objects will be apparent'in the l followingY description vof which the drawings form a part.`

Figure 11 is afront elevational view partially in? about `its fulcrum 3l section illustrating the device of the presentinvention. y f

Figure 2 isa side elevational view-of the appaf ratus of Fig. 1 Ashowing the `throttle connections. Y Figure T3 'is ya view in elevation vofi-the opposite or left-hand side of Fig. 1 showing the cut-off lever inlits operating position and indicating .the non-operating position of; the lever in dash'linesf. 'Figure '4 is avieW in section of the mechanism for controlling the cut-off lever. Figure' is a View in section of a throttle ,and cut-'off valve of the present invention.

Figure Gis asection taken along the line vB-- of Fig. 5 Villustrating the cut-oli valve in its open position andthe throttle in a throttling position. 10

"Figure 7 is a section similar to Fig. 6 showing the'cut-oi valve initscut-ol position.

"Figure 48 is a View vin section of the apparatus for `controlling the throttle portion of the valve.

' 'With reference to Fig. '1, the device of the 15 present invention consists of a valve body i hav- -ing flanges adaptedr for connectionto'the power mediurnl-supply conduit 3 .and the engine 5, as shown in Fig. I2. Mounted on one side of the valve body listhe'plunger casing l. rResting on 20 the top of the Yplungervcasing l `is a weight 9 provided-With a pin l l on which is rotatably secured a lrod I3.` The'rod I3 connects the Weight Sand the crankl lever l5 which is secured tothe shati'i by the key t9. If the weight 9 is raised, 25 the lrodl3 will -raise theouter end ofthe crank I5, thus* `rotating shaft l1.

'Frorn vtheopposite side'ofthe valve'body i a shv "it 2| extends to which is secured a cut-oli lever 23 having a Weight '25 at its free end. This 30 cut-off lever will rotate "the shaft-2l and thus control the cut-off portion of the valve. Ordinarly, the -lever v23 is maintained by the trip lever 21 inthe position indicated by the dash lines in Fig. 3. Y y -3 The trip lever 2f! l'has a. notch 29 on Which the bolt 26' of lever '5123 rests. 'The lowerrnostor actuated `position of the lever `23 is determined Aby theposition of the stop 24. It is,.of'course, impossible to maintain the lever 23 in its upper 0 position, unless the trip lweight 133 is also maintained :in 'its upper "position, since the trip pin 35, extending `'from ithe trip weight 33, bears against .the :trip lever `21 as indicated in Fig. 1.

'Assuming fthat the cut-01T lever 23 is in its upper position and that trip weight 33 'is lin its upper position', it is readily seen lthat, should the ftrip weight 33 seek to reach its lower position, the-trip pin 3 5 Lwill strike the horizontal arm of the ytrip lever 21and rotate the lever 50 causing the supportingA notch 23 to rslipfrom beneath the trip -lever bolt 26 -and'a1low-the weight 25 -to vmove the trip lever'2'3 'to yfits lowermost position.

The means for maintaining weight 33 `in lits 55 ported sleeves 15 and 11.

upper position are shown in section in Fig. 4 wherein it will.be seen that the weight 33 has an extending arm 31 provided with a passage 39. In oi der to guide the movement of the extension 3l, a guide casing 4| is provided which has a recess 43 and a passage 45 to receive the flange push button 41. This push button 41 is employed when the weight is being reset in its upper position before the engine has begun operating. When the push button 41 is moved into its left-hand position, the ange will extend into the passage 39 and maintain the weight in it: upper position, thus providing a manual means for controlling the position of the weight 33.

The automatic means consists of a diaphragm chamber casing 49 in which a diaphragm 5| is mounted. The diaphragm 5I divides the casing into two chambers 53 and 55. The chamber 53 is supplied with oil under pressure from the engine lubricating system by the conduit 51 opening thereinto.

Centrally located on the diaphragm and extending through a passage in the diaphragm casing 49 is .a push rod 59. Any position assumed by the push rod 59 will,` of course, depend upon the pressure of the oil in the chamber 53. As is shown, the push rod bears against a crank 6| fulcrumed at 63 and normally urged in a counter-clockwise direction by the spring 65 adjustably secured on the diaphragm casing 49.

The automatic means comes into operation to hold the trip weight 33 in its upper position when the engine is operating under normal conditions. Before starting the operation of the engine, as has been pointed out, the push button 41 is employed to maintain the Weight in its upper position. As the engine is started and the speed of the engine increases, the oil pressure also increases and is supplied to the chamber 53 where it moves the diaphragm 55 towards the left until the push rod 59 moves the crank 5| and causes the automatic button 61 attached to the crank 6| to enter the passage 39 to hold the weight inV its uppermost position. At the same time, the button 41 is pushed out of the passage 39 into recess 43. Should the pressure now decrease for any reason, the automatic button 61 will be moved toward the left out of the passage 39 and permit the lweight 33 to drop. This movement occurs whenever the spring 65 is sufciently strong to overcome the pressure of the oil in the chamber 53 bearing against the diaphragm 55 and thus the spring 65 determines the oil pressure at which the power medium is cut olf.

As the weight 33 drops the trip lever 21, as has been explained, will be released and the cut-off portion of the valve will serve to stop the now of power medium to the engine. In order to understand how the engine is throttled or the power medium to the engine cut-off during operation, it is necessary to refer to Fig. 5 illustrating the details of the valve. Valve body I has an inlet port 69 and an outlet port 1I. Between these two ports is a chamber 13 wherein are located The outer sleeve 15 is designed to throttle the power medium iiowing through the valve and it is provided with ports 19 which communicate with the inlet port 69.

This sleeve 15 is rotatably mounted in the chamber 13 and is rotatably controlled by the shaft I1 which passes through the end of the sleeve and is fastened thereto by the-nut 83.4 In order that the sleeve shall not move relative to the shaft I1 a flange 85 is provided on the shaft which seats on the shoulder 81 provided on the sleeve. It is thus possible by tightening nut 83 to securely fasten the sleeve 15 to shaft I1. The sleeve and shaft are maintained in the valve by a bonnet 89 secured to the valve body I in any suitable manner and bearing against the ange 85. The shaft passes through this bonnet and leakage through the bonnet 89 around the shaft I1 is prevented by providing packing 9| maintained in position by the packing nut 93.

By threading the outer end of the shaft the crank lever I5 may be secured thereto in the manner about to be described. The end of the crank lever I5 is provided with a housing 95 secured thereto by the key I9. Fingers 91 extending from the bonnet 89 have a groove 99 in which the flange of the housing rests. The flanges on the housing 95' do not extend completely around the housing since they are cut oif as indicated in Fig. 2, one side being indicated by the dotted lines. In connecting the housing to the shaft it is apparent from Fig. 2 that, when the crank lever l is vertical, the fingers 91 permit the entrance of the housing and, upon rotation, the flange |00 will mesh with the grooves to hold the housing in position. Within the housing 95 is an adjustable nut IOI which is threaded on the shaft I1 and provided with Spanner holes |03 in order that it may be turned to move the shaft I1 in or out of the valve. Obviously, when the sleeve is secured to the shaft, the turn of this adjusting nut |0| will move the sleeve longitudinally within the chamber 13 and in this manner the sleeve 15 may be held in any desired position against axial movement in recess 13. The other or cut-off sleeve 11 is rotatably mounted within the throttle sleeve 15 and is provided with inlet ports |05 normally communicating through the ports 19 with the inlet port 69 of the valve to permit power medium to pass within the sleeve 11. It also has outlet ports |01 opening into the exhaust passage 1| of the valve in order that the steam may pass from within the sleeve to the engine.

The sleeve 11 is maintained in the valve by the bonnet |09 holding the flange III in the groove II3 of the valve body. In this manner the sleeve 11 is held within the valve in such manner that it can only be rotatably moved. The means for rotating the sleeve consists of the cut-off lever shaft 2| to which the cut-olf lever 23 is fastened by a pin ||4. The portion of the shaft 2| engaging the sleeve 11 is fashioned with a square head II5 resting in socket |I1 formed at the end of the sleeve. The shaft 2| is journalled in the bonnet |09 by the bearing II9 and the conical surface of the square head |I5 of the shaft 2| is pressed against this bearing by the spring I2| placed in the socket recess |22. It will thus be seen that means have been provided whereby movement of the lever 23 will rotate shaft 2| and the sleeve 11.

In order to understand how the throttle portion of the valve operates, it is necessary to refer to Fig. 6 which shows the sleeve 15 inl a throttling position while the sleeve 11 is maintained inl its open position. Obviously, as the sleeve 15 is rotated in a clockwise direction, it will tend to cut down the size of the opening through sleeve 15 between the inlet passage 69 and the interior of sleeve 11. Conversely, when it is rotated in a counter-clockwise direction, it will open the ports of communication 19 through the sleeve 15 until the ports 19 and |05gin both sleeves Lare ,concentric at which time.`- the.y interior of sleeve 15P-,Will be in opencomnuinication wvithl thesource of `:powenmedium supply. l

What `occurs when ithe vtrip lever `hasireleaseol the cut-off lever can .fbe seenvby Fig. 1.7. When this lever drops, .it rotates v:the inner., sleeve..'|'|

until its ,ports :L65 are ;completely fout, .of en"- into engagement with -the-sports .-'|.9:by raising" the cut-.01T .lever 2:3 Aand.itslrespective weight25. With respect .to Athe throttle -control apparatus illustratedinlig, it will benoted thatit vconsists ofraftubular plunger ,casing 1 vthrough which extends .a plunger L23. The lower `end .of the casing receives a :bushing L25 in which .is threaded an oil .supply conduit |21. and by means of which oil pressure may be'supplied to the bottom face |.-?..9.'of theplunger |23. yA .washer |'3I resting on a shouldery |32 placed between ,the bushing |15 and the bottom face |29 of the .plunger ein :order Yto secureone end of the spring ISSbymeans ofpin |35.

The spring |33 extends through .the bore |31 which passes through the entire length of the plunger |23 4and is .adapted to ,besecured at its opposite end on the lug |39 provided vonth'e plug IBI which `is threaded into the upperend of the plunger. To prevent any-oil which might pass `through the bore .and .escape from .the plunger' at the union of the plug |4| with the plunger |23 a sealing washer AM2 .is maintaineditherebetween. The weight `9 being'furnished with a bore is adapted to t around the plunger |23 and has a recess |43 in lwhich .the .collar |45,

surrounding the plunger |23, isplaced. This collar is secured to the-plunger by .the pin |41. When oil pressure is supplied through conduit |21 in sufficient degree to overcome `tension of the spring |33 vand the inertiaof theV weight VS,`

it will raise the plunger |23 and move the Weight 9 away from the plunger casing Since the pin II is carried on the weight and .has Va rod I3 connected thereto, the rising of the weight will rotate the crank lever I5 in a clockwise direction and thus rotate the throttle sleeve 'I5 to a throttling position. With this arrangement, as the speed of the engine increases, the oil pressure likewise increases and tends to move the weight upwardly so that, as the oil pressure increases, the throttle valve is moved closer to its closing position and thus tending to maintain the engine speed at a constant speed.

It will thus be seen that a device has been provided wherein the speed of the engine driving a compressor can be regulated by the degree of oil pressure on the engine. If, for any reason, the oil pressure increases, the engine will be throttled and, if the pressure continues to increase, the operation of the engine will automatically be stopped.

I claim:

1. In an engine driven compressor, the combination of a valve to control the flow of power munioating "with .the inlet chamber, :a second rotatable Asleeve'wi'rlhin .the .outer sleeve having ports through 'the `.thereof .normally communicatingv with vthe outlet ,chamber and :com-

municating through the outer sleeveports withv the inlet `chamber, meansresponsive to said oil pressure to rotate .the outer rsleeve .to limit .the

bination of va valve .to control .the flowof `power medium to the engine in accordance with variations -in `the pressure :of the oil in .the engine lubricating system comprising a lvalve body .hav-

'ing an inlet chamber and an outlet chamber, a

rotatable outer sleeve between the inlet and 2. In an engine ldriven compressor, the comoutlet vchambershaving ports through the walls thereof, a second rotatable v4sleeve within the outer sleeve having ports throughv the walls thereof, -means responsive to said' oil pressure to normally maintain the ,ports in sai-d second sleeve in open communication with the inlet and outlet chambers and, adapted to prevent powerv medium owthrough ,said ports upon rotation, and oil pressure responsive ymeans to rotate the outer sleeve to move `its ports into andl out of registry with the :inner 'sleeve ports to thereby throttle thefluid flowing from theinlet chamber to the outlet chamber. i

3.1In an engine driven compressor, the combination of a valve to control the flow of ,power medium to theenginein accordance with variations in the pressure ofthe oil in the enginev lubricating Vsystem comprising a valve body having inlet and outlet chambers, a hollow rotatable means provided with ports normally in communication with the inlet chamber, aisecond hollow rotatable means provided with portsnormally in communication with the outlet chamber and the inlet chamberthroughthe ports of the first said ,means.means responsive `to said 4oil f pressure to rotatefthe rstsaid means to throttle thevow of power medium to the second means and means to rotate the second means to prevent communication between the inlet and outlet chambers at a predetermined oil pressure.

4. In an engine'driven compressor having an engine lubricating system, the combination of a valve to control the flow of power medium to the engine, a rotatable outer sleeve in the valve having ports enabling power medium to flow therethrough, a rotatable inner sleeve having its ports corresponding with the ports in the outer sleeve, means responsive to pressure Variations in said lubricating system to rotate the outer sleeve to throttle the flow of power medium,

y and oil pressure responsive means to rotate the inner sleeve to prevent the ow of power medium.

5. In an engine driven compressor, rthe combination of a valve to control the flow of power medium to an engine in accordance with variations in the pressure of the oil in the engine lubricating system comprising a valve body having an inlet chamber and anoutlet chamber, a rotatable outer sleeve between the inlet and outlet chambers provided with ports whereby fluid medium may flow yfrom an inlet chamber tothe outlet chamber, asecond rotatable sleeve within the outer sleeve having ports corresponding to and normally aligned with in said -outer sleeve, oil pressure responsive means to rotate the outer sleeve to throttle the iiow of power medium through the valve in accordance with an increase in the speed of theV engine, and secondary oil pressure responsive means to rotate the second sleeve to prevent the flow of power medium through thevalve when the oil pressure reaches a predetermined pressure.

6. In an engine driven compressor, the combination of a valve having inlet and outlet chambers to control the flow of power medium to the engine in accordance with variations in the pressure of the oil in the engine lubricating system, rotatable means interposed between the inlet and outlet chambers having ports opening into the inlet chamber, means to rotate -the rotatable means, oil pressure operated means to actuate the last said means to throttle the ow of power medium from the inlet chamber, a second rotatable means within the first said means having ports adapted to co-act with the ports of the rst rotatable means and to enable power medium to flow from the inlet chamber to the outlet chamber, means to rotate said second rotatable means to stop the flow of power medium from the inlet chamber to the outlet chamber, and oil pressure actuated means to normally prevent operation of the last said means.

'7. In an engine driven compressor, the corn--l bination of a valve having inlet and outlet chambers to control the flow of power medium to the engine in accordance with variations in the pressure of the oil in the engine lubricating system, means interposed between the inlet and outlet chambers to throttle the fiow of power medium to the engine, means within the rst said means havingk ports to enable power medium to flow therethrough from the inlet chamber to the outlet chamber, means to rotate said second means to close said ports and to prevent the ow of power medium therethrough, and oil pressure actuated means to normally prevent operation of the last said means.

8. In an engine driven compresser, the combination of a valve having inlet and outlet chambers to control the flow of power medium to the engine in accordance with variations in the pressure of the oil in the engine lubricating system, a rotatable sleeve having ports communicating with the engine, a shaft to rotate the sleeve, an oil pressure actuated plunger to control the shaft, levers connecting the shaft to the plunger, a second rotatable 'sleeve within the first said sleeve having ports to enable power medium to flow from the inlet chamber to the outlet chamber through the ports of the first said rotatable sleeve, means normally enabling power medium to flow through the ports of both said sleeves from the inlet chamber to the outlet chamber adapted upon rotation to prevent the flow of power medium, and oil pressure actuated means to control operation of the last said means.

9. In an engine driven compressor, the combination of a valve to control the flow of power medium to the engine in accordance with variations in the pressure in the oil lubricating system, a rotatably ported outer sleeve in the valve, a rotatably ported inner sleeve within the outer sleeve, a shaft to rotate the outer sleeve, an oil pressure actuated plunger to control the shaft, levers to connect the plunger and shaft, a square head shaft to rotate the inner sleeve, a weighted lever secured to said square head shaft, and an oil pressure actuated mechanism to normally maintain said square head shaft in one position and adapted to release said shaft when the fluid pressure decreases to rotate the inner sleeve to stop the ow of power medium to the engine.

10. In an engine driven compressor having an engine lubricating system, the combination of a valve having inlet and outlet chambers to control the flow of power medium to the engine, means interposed between the inlet and outlet chambers comprising a rotatably ported sleeve having ports opening into the inlet chambers, means to rotate the sleeve, a pressure actuated means to operate the last said means to throttle the flow of .power medium from the inlet chamber in accordance with variations in pressure in said lubricating system, means within first said means normally enabling pressure medium to flow to the engine and adapted to `stop the ilow of pressure medium to the engine, and a lubricating oil pressure responsive means to normally render the last said means ineffective.

CHARLES E. BLANK.

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