US1754218A - Compressor-unloader governor - Google Patents

Description

April 15, 1930. B, s, MKMAN 1,754,218

COMPRESSOR UNLOADER GOVERNOR Filed May 51, 1928 INVENTOR BURTON S. NKMAN BYWW ' ATTQ EY l rl application filed May 31,

This invention relates to fluid compressors and more particularly to a governor device for controlling the loading and unloading of the compressor,

a The principal object of my invention is to provide an improved compressor unloader governor, which is simple in construction and which can be cheaply manufactured.

Tn the accompanying drawing, the single figure is a diagrammatic view, partly in section, oil a portion oil a fluid compressor and having associated therewith an unloading means and a compressor unloader governor constructed in accordance with my invention.

The construction shown in the drawing comprises a fluid compressor cylinder 1, shown in part, and having a cylinder head 2 provided with a valvechamber 3, containing the usual discharge valve 4L, for controla ling communication from the fluid compres sor 1 to the usual storage reservoir 5.

An unloading valve 6 controls communication ifrcm the compressing cylinder to an atmospheric port 7 and is provided with an operating stem 6. Carried at the outer end of the stem 3 is a member 9 which is subject to the pressure at a coil spring 10 acting through the stem 3 to urge the valve 6 to. its seat. i

Pivotally mounted on a pivot pin ll car ried by the head 2 is a lever 12 having a long arm 13 provided with an adjustable screw 14 adapted to engage the end of the valve stem 8. A spring 15 interposed between the cylinder head 2 and the arm 13 urges the arm away from the stem 8.

Tht short arms 16 ot the lever 12 carries an adjustable screw 17 to which the movement of a flexible diaphragm 18 is transmitted an through a ball 19. The chamber 20 at one side of the diaphragm 18 is connected to a pipe 21 which leads to my improved governor device 22.

The governor device 22 comprises a casting 23 which is mounted in a casing 2d and lit CUMPHIlEflSUIEt-UNLQADER RGi-UVEENUR mounted in a cavity in the casting is a double beat piston head 25 having valves 26 and 27. A Bourdon tube 28 is mounted in the casing 24 and has one end secured in the casting 23 in a member 34, secured to the free end of s the Bourdon tube 28. The screw 36 is provided with a head 32 and is maintained in its position of adjustment by a loclr nut 33..

Assuming that the screw 36 has been adjusted tor the pressure at which it is desired to unload the compressor, at all pressures below this pressure, the spring action oi the tube will exert a downward pressure on stem 31 to hold the valve 27 seated against the pressure in pipe 30..

When the pressure in pipe 30 has increased to a point where the internal ressure in the tube 28 plus the pressure actin on the enposed area oi the valve 27 ercee s the spring action of the tube 28, the valve 2'? will be slightly lifted from its seat, permitting leahage of fluid from pipe 30 to the space below the piston head 25,

The pressure of fluid from pipe 30 will then act on the tull area of piston head 25, so

as to cause a quick upward movement thereof and thereby causing the valve 26 to seat.

lit will be noted that the area oii the valve 26 is greater than that of the valve 27, so that although the spring action of the tube23 is increased by its upward movement, the fluid pressure acting on the piston head 25 will be sutflcient to hold the valve 26 seated.

on valve 27 is unseated, fluid under pressure is supplied from the reservoir 5 through pi e 30 to pipe 21, by leakage past the piston ead 25, and thence to diaphragm chamber 18. The diaphra m 18 is then moved upwardly, so that the ever 12 is actulid 5 operates without compressing fluid into the "reservoir 5.

' When the fluid pressure in the reservoir 5 has fallen sufiiciently to permit the spring action of the tube 28 to overcome the pressure 10 of fluid acting on the under side of the piston head 25, the valve 26 will be slightly lifted from its seat and leakage of fluid from pipe 30, past the piston head 25, to the chamber above the piston head will occur.

The area of the exhaust port 35 is so restricted that the pressure above the piston head'25 will build up sufficiently to permit the spring action of the'tube 28 to quickly shift the piston head so as to cause the valve 27 to seat.

With valve 26 unseated, fluid is vented from diaphragm chamber 20 through ipe 21 to the atmosphere, by way of port 3 so that the pressure of s ring 15' acts to shift the arm 13 upwardly, t hereby permitting the valve 6 to seat. The compressor then operates to compress fluid into the reservoir 5. 1

While one illustrative embodiment of the invention has been described in detail, it is not my intention to limit its scope to that emb0.di ment or otherwise than by the terms of the appended claims. I

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is

1.- The combination with a fluid compressor unloading device having a movable abutment operated by an increase in fluid under pressure for unloading the compressor, of a governor comprising a Bourdon tube subject to the pressure of fluid compressed by the compressor, valve means for controlling the fluid pressure on said abutment, and a member carried by said tube for engaging said valve means, the resiliency of the tube urging said valve means in one direction and the expansion of the tube by fluid under pressure urging 'said member away from said valve means. I

2. The combination with an unloading device for a fluid compressor operable by variations in fluid under pressure, of a governor device for controlling the fluidpressure for operating said unloading device comprising a Bourdon tube subject to the pressure of fluid compressed by the compressor, valve means for controlling. the fluid pressure on said unloadin device and having a valve stem, and a mem er carried by said tube for engaging ,0 said stem, the tube being under initial tension to urge the valve means in one direction,

and the expansion of. the tube by fluid under pressure urging said member away from said valve stem.

3. The combinationwith an unloading de-.

vice for a fluid compressor operable by variations in fluid under pressure, of a governor devicefor controlling the fluid pressure for operating said unloading device comprising a Bourdon tube subject to the pressure of fluid compressed by the compressor, a double 1 beat valve device for controlling the supply and release of fluid under pressure to and from said unloading device and having a. valve stem, and a member carried by said tube for engaging said stem, the resiliency of the tube itself being utilized to urge said member into engagement with said valve stem for operating said valve device to release fluid under pressure from said unloading device.

4. The combination with an unloading device for a fluid compressor operable by variations in fluid under pressure of a governor device for controlling the fluid pressure for operatin said unloading device comprising a Bour on tube subject to the pressure of fluid compressed by the compressor, a valve forsupplyingfluid under pressure to said unloading device, a valve for venting fluid from said unloading device, astem for operatin said valves, and a member carried by sai tube for engaging said stem, the stem being operated by the resiliency of the tube for seating one valve and the expansion of the tube by fluid under pressure urging said member away from said stem. 5. The combination with an unloading-device for a fluid compressor operable by variations in fluid under pressure, of a governor device for controllin the fluid pressure for operating said unloa ing device comprising a Bourdon tube subject to the pressure of fluid compressed ,by the compressor, a valve for supplying fluid under pressure to said unloading device, a valve for venting fluid from said unloading device, a stem for operating said valves, a member carried by said tube, and an adjustable screw mounted in said member for o crating said stem.

6. The com ination with an unloading device for a fluid compressor operable by varia- -tions in fluid under pressure, of a governor device for controlling the fluid pressure for operating said unloading device comprising a Bourdon tube subject to the pressure of fluid compressed by the compressor, valves for controlling thesupply of fluid under pressure to and its exhaust from said unloading device, a stem for operating said valves means carried by said tube for en aging said stem, and a piston head carried y said stem and subject to fluid pressure compressed b the compressor, the stem and said valves eing operated by said means in one direction, and fluid under pressure on said piston urging said valves in the opposite direction.

7. The combination with an unloading device for a fluid compressor operable by variations in fluid under pressure, of a governor device for controlling the fluid pressure for operating said unloading device comprising a lBourdon tube subject to the pressure of fluid compressed by the compressor, a valve for supplying fluid under pressure to said un loading device, a stem operated by said tube for operating said valve, and a piston head carried by said stem and exposed to fluid compressed by the compressor When said valve is lifted from its seat.

In testimony whereof I have hereunto set my hand, this 23rd day of May, 192&

v BURTON S. AIRMAN

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