US3586435A

US3586435A - Electrolytic pump operated gas bearing

Info

Publication number: US3586435A
Application number: US882174A
Authority: US
Inventors: Carlo Del Carlo; Keith R Jenkin
Original assignee: Speedring Corp
Current assignee: Speedring Corp
Priority date: 1969-12-04
Filing date: 1969-12-04
Publication date: 1971-06-22
Anticipated expiration: 1988-06-22

Abstract

There is disclosed a hydrostatic gas bearing supplied with hydrogen at high pressure from an electrolytic cell operated in a pumping mode. A high purity hydrogen gas at high steady pressure is transmitted through an electrolytic cell using hydrogen diffusion anode and a hydrogen diffusion cathode and an electrolyte therebetween. With a voltage across the electrodes and with the anode and cathode chambers charged with hydrogen and a flow restrictor in the external fluid path between the chambers, hydrogen is transmitted through the anode, electrolyte and cathode to develop superatmospheric pressure in the cathode chamber and subatmospheric pressure in the anode chamber. The hydrostatic gas bearing with its associated load device is suitably operated in a closed container with the high pressure hydrogen applied to its inlet passage and the container being partially evacuated by connection to the low pressure chamber of the electrolytic cell thereby reducing the windage loss in operation of the load device.

Description

OR 3 t 586 43s willow utalcb W 172] Inventors Carlo DelCnm liticn:

Keith R. Jenkin. Warren. both of. Mich. [Zll Appl No 882.174 [22] Filed Dee. 1969 [45] Patented June 22. 197] [73] Assignee Speedring Corporation Warren. Mich. 3 s.)

[54] ELECTROLYTIC PUMP OPERATED GAS H H H 3,586,435

Primary E.raminerMartin P Schwadron Assistant Examiner Frank Susko Attorney-Barnard, McGlynn and Reising ABSTRACT: There is disclosed a hydrostatic gas bearing supplied with hydrogen at high pressure from an electrolytic cell operated in a pumping mode. A high purity hydrogen gas at high steady pressure is transmittedlthrough an electrolytic cell using hydrogen diffusion anode and a hydrogen diffusion cathode and an electrolyte therebetween. With a voltage BEAUNG across the electrodes and with the anode and cathode cham- 25 Clalms, 9 Brown; Figs.

bers charged with hydrogen and a flow restrlctor in the exterl l Cl 350/7 nal fluid path between the chambers, hydrogen is transmitted 303/910429 through the anode, electrolyte and cathode to develop su- [Sl] Int. Cl ..G02bl7/00, peratmospheric pressure in the cathode chamber and ub t- F 1 6C l Col b 13/04 mospheric pressure in the anode chamber. The hydrostatic gas [50] Field 0' Search 204/ l 29; b i ith its s iated load devige is suitably operated in a 350/ 7 closed container with the high pressure hydrogen applied to its inlet passage and the container being partially evacuated by [56] Rdmnm and connection to the low pressure chamber of the electrolytic cell UNITED T T PATENTS thereby reducing the windage loss in operation of the load 3,448,035 6/1969 Sert'ass 204/278 device.

y In 5 34 .k 24! s 750 2/8 l I A -..""l "5 (6 i POWER 4 1/0 ELECTROLYTIC PUMP OPERATED GAS BEARING This inventiori relates to hydrostatic gas bearings and, more particularly, to process and apparatus for supplying gas pressure to such bearings.

It has been a common practice heretofore in the operation of hydrostatic gas bearings to utilize a conventional compressor, usually of the piston type, for supplying air or other gas at high pressure to the journal of the gas bearing. While such an arrangement is suitable for some applications, there are certain gas bearing applications where the mechanical compressor poses difficult problems and is highly objectionable. Such compressors are extremely noisy and produce mechanical vibrations of large amplitude over a wide frequency spectrum. Consequently, unless the equipment is suitably muffled and isolated, it is a source of interference with surrounding equipment. Additionally, such compressors are relatively large and heavy and require substantial power, operate at a relatively low efficiency and require continual maintenance. Generally, gas bearings operated with compressors utilize atmospheric air and hence involve gaseous components of relatively high viscosity. Even when a selected gas is recirculated in aclosed system by a compressor, it is subject to a high degree of contamination by the compressor, which may impair operation of the bearing or the device associated therewith.

In a particular application a hydrostatic gas bearing is employed in a laser scanner of the type wherein a mirror is rotated at exceedingly high speeds over a wide dynamic range. In such equipment great precision is required in speed control and because of the optical system a high degree of stabilization must be provided. Because of the high rotative speeds, the scanner is desirably operated in a closed chamber which is evacuated to a low gas pressure to minimize the windage loss. Since the optical transmission path must extend through the closed chamber, windows are provided therein which, in addition to the mirror surfaces, must be kept free of contamination to avoid impairment of the transmission path. In such an application the conventional compressor leaves much to be desired. The vibration produced by the compressor, unless satisfactorily isolated, will interfere with the proper functioning of the laser scanner. Furthermore, pulsations in the gas pressure supplied to the bearing by the compressor may produce some disturbance in the scan rate unless suitably damped. Contaminants such as hydrocarbons from the compressor and water vapor entrained in the gas may be deposited upon the optical surfaces of the mirror and windows in the laser scanner and impair the optical transmission. Furthermore, in the operational environment for such equipment the noise of the compressor is highly objectionable.

It has been recognized for some time that hydrogen gas has properties which are most desirable for use in the hydrostatic gas bearing. Hydrogen, for example, has a very low viscosity coefficient and, therefore, the losses in a high-speed bearing are minimized. It has a high thermal conductivity and is nonreactive with other materials used in connection with gas bearings. It is readily available and economical in commercially pure form. One major drawback, however, of hydrogen gas has thus far militated against its use in gas bearings; that is the potential hazard of explosion when stored in substantial quantity. Because of this characteristic the so-called cylinder hydrogen has not been acceptable for use in aircraft and other environments where there is a risk of explosion.

In accordance with this invention, process and apparatus are provided for supplying. gas, particularly hydrogen gas, to a hydrostatic gas bearing in a manner which obviates the aforementioned problems in the prior art. This is accomplished by generating a gas flow by means of an electrolytic cell, restricting the flow to produce a relatively high pressure and supplying the high pressure gas flow to the inlet passage of the bearing. This process and the apparatus required therefor is especially well adapted for the production of high purity hydrogen gas at high, steady pressure. This is desirably achieved by using an electrolytic cell'of the type-including a hydrogen diffusion cathode for evolving and transmitting hydrogen gas at high pressure from an electrolyte to a high-pressure chamber. Desirably, the anode is of the same material adapted for hydrogen diffusion and transmits hydrogen from a low-pressure chamber to the electrolyte. With a voltage across the electrodes, hydrogen gas is supplied at superatmospheric pressure to the bearing and recirculated through the electrolytic cell. The bearing and its load device may be operated in a closed chamber with the high pressure being applied to the journal which communicates with the low-pressure anode chamber of the cell and is thereby pumped to subatmospheric pressure. The cathode and anode electrodes are preferably formed of a solid metal alloy of palladium and silver and the electrolyte is desirably a highly concentrated aqueous solution of sodium hydroxide. The electrodes are suitably of tubular configuration and one may be disposed within the other with the electrolyte therebetween. A plurality of the electrolytic cells may be interconnected electrically with the fluid circuits connected in parallel to supply the required volume of gas flow to the gas bearing. Pressure responsive means connected with at least one of the pressure chambers and with the voltage source may be utilized to vary the cell current to regulate the pressure at a desired value.

A.more complete understanding of this invention may be obtained from the detailed description which follows taken with the accompanying drawings in which FIG. 1 is a diagrammatic representation of the inventive system including a hydrostatic gas bearing and electrochemical pump;

FIG. 2 shows a single electrolytic cell adapted. for use in the present invention;

FIG. 3 is a fragmentary view of a bank of electrolytic cells of the type shown in FIG. 2; and

FIG. 4 is a diagram showing the interconnection of plural cell banks.

Referring now to the drawings, there is shown an illustrative embodiment of the invention in a system utilizing a hydrostatic gas bearing in a laser scanner. in general, the system comprises a laser scanner to including a hydrostatic gas bearing which is supplied with gas pressure from an electrochemical pump 12 which is provided with a power supply and control system 14.

Consider first the laser scanner 10 which may be regarded as the load device or utilization device of the system. It comprises a sealed envelope or container 16 within which is disposed a fixed bearing shaft 18 having its ends fixedly mounted in the opposed end walls of the container 16. The shaft 18 is provided with a thrust plate 20 adjacent one end and a similar thrust plate 22 adjacent the other end. A spinner assembly or rotor 24 having a smooth axial bore is fitted over the shaft 18 between

thrust plates

20 and 22 with exceedingly small clearance and very close tolerances. In order to rotatably drive the rotor 24, a hysteresis motor 26 is mounted inside the container 16 with its stator secured thereto and with a hysteresis ring 30 secured to the rotor 24. The rotor 24 is provided with a multifaceted mirror 32 which includes a plurality of reflective surfaces 34 each of which is disposed on the rim thereof and extends in a tangential plane. The chamber 16 is provided with

optical windows

36 and 38 disposed radially outwardly from the reflective surfaces 34.

The hydrostatic gas bearing of the laser scanner 10 comprises a journal 40 which is supplied with gas at high pressure through an inlet passage 42 in the shaft 18. The passage 42 includes a set of radially extending orifices 44 and another set of radially extending orifices 46 which supply a gas under pressure to the radial portion of the journal 40. The inlet passage 42 also includes a set of axially extending orifices 48 in the thrust plate 20 and a set of axially extending orifices $0 in the thrust plate 22 to supply gas under pressure to the axial portion of the journal 40. The orifices which admit gas to the journal 40 and the journal itself constitute flow restrictors in the path of the gas flow in the inlet passage 42. The journal 40 is provided with an outlet passage 54 formed by the clearance between the rotor 24 and the thrust plate 20. Another outlet passage 56 is provided by the clearance between the rotor 24 and the thrustplate 22. Accordingly, a substantial pressure differential occurs across the flow restrictors between inlet passage 42 and

outlet passages

48 and 50.

In operation of the laser scanner with the hydrostatic gas bearing just described, gas is supplied at high pressure to the inlet passage 42 from a supply conduit 58 and is discharged at low pressure through the

outlet passages

54 and 56 to the interior of container 16 from whence it is exhausted by a return conduit 60. With the hysteresis motor 26 energized and the rotor 24 rotating at high speed, the operation of the optical system may be initiated. This system includes a laser (not shown) from which a laser beam is transmitted through the window 36 and is reflected successively by the reflective surfaces 34 to produce a repetitive scan pattern. A typical laser scanner bearing requires hydrogen flow of about 0.2 cubic feet per minute with an inlet pressure of about 150 p.,s.i. absolute. An outlet pressure below atmospheric such as about 5 or 6 psi. absolute is desired.

In order to supply the gas under pressure to the hydrostatic gas bearing, there is provided, in accordance with the present invention, an electrochemical pump 12 which will be described with reference to FIGS. 2, 3 and 4. The elec trochemical pump 12 comprises at least one electrolytic cell,

such as that shown in FIG. 2; in the illustrated embodiment it comprises a multiplicity of such cells.

It is well known that hydrogen diffuses into some metals and when such a metal, e.g. palladium, is made the cathode in an electrolytic cell, hydrogen will pass through the metal at'room temperature in appreciable quantities. The diffusion rate of hydrogen increases rapidly with temperature. When the palladium cathode is formed as the wall of a gas chamber, which may be vented through a suitable flow restrictor, hydrogen pressure of several hundred pounds per square inch may be built up in the chamber. lt is known that other metals such as iron and aluminum also transmit hydrogen to a substantial extent and certain other metals show a lesser degree of hydrogen transmission. The phenomena has been demonstrated using either an acid electrolyte, such as sulfuric acid, or a base electrolyte such as sodium hydroxide. An application of such an electrolytic cell for the generation of hydrogen is disclosed in US. Pat.'No. 2,749,293.

Such an electrolytic cell has heretofore been proposed for use in generating pure hydrogen as a carrier gas for gas chromotography by the process of water electrolysis. Such a cell and the process for operation thereof utilizing a cathode formed of a metal alloy of palladium and silver is disclosed in US. Pat. No. 3,448,035.

A distinct modification of such water electrolysis cells for the production of hydrogen at elevated pressures has also been proposed whereby the electrolytic cell may be operated in a hydrogen pumping mode. In this arrangement both the anode and cathode are fonned of a metal adapted for hydrogen diffusion and a low-pressure hydrogen supply chamber utilizes the anode as a part of the chamber wall and a high-pressure hydrogen chamber utilizes the cathode as part of the chamber wall. A liquid electrolyteis disposed between the electrodes and the chambers are charged with hydrogen gas. With a voltage applied between the electrodes, the current is proportional to the hydrogen transferred from one chamber to the other. At the anode hydrogen gas dissociates at the gas phase surface and enters the metal and diffuses to the electrolyte side where it is anodically consumed. At the cathode surface the action is reversed with the hydrogen formed at the electrolyte interface entering the metal and diffusing to the gas phase side. The reactions involved indicate that only hydrogen ha been transferred from the anode chamber to the cathode chamber. If the hydrogen gas pressure in the cathode chamber is equal to that in the anode chamber the theoretical voltage and the power required would be zero. However, there are small power requirements because of overvoltage at each electrode and ohmic losses due to the current between the electrodes. The excess voltage can be ofivery low value such as less than one-tenth volt and depends upon the electrode current density, transfer for a given electrode area.

In this arrangement if the flow of hydrogen out of the cathode chamber is restricted, superatmospheric pressures of hydrogen such as several hundred pounds per square inch may be developed. Similarly, if the flow of hydrogen into the anode chamber is restricted, the hydrogen pressure therein will be reduced to subatmospheric values such as 5 or 6 pounds per square inch.

in this type of cell the presently preferred construction utilizes a cathode and an anode of thin tubular membranes of an alloy of about 25 per cent silver and about 75 per cent palladium. The electrolyte is a concentrated aqueous solution of approximately weight percent sodium hydroxide. The voltage between electrodes is maintained at about 0.09 volts and the cell is maintained at an operating temperature of approximately 200C. An important requirement in the operation of the cell is that substantially all of the hydrogen at the cathode enter the metal with no hydrogen gas bubbles formed on the electrolyte side. The ideal condition is referred to an l00 percent hydrogen transmission. In practical cells this condition has been approached for extended operating periods and it has been found that hydrogen transmission slightly less than the ideal condition produces satisfactory performance.

Referring now to FIG. 2, there is shown in diagrammatic fashion an electrolytic cell 60 of the type referred to above for operation in a hydrogen pumping mode. The cell comprises a container 62, suitably of stainless steel, within which is disposed a tubular anode 64 of nonporous or solid metal, preferably an alloy of 25 percent silver and 75 percent palladium. The outer end of the anode electrode 64 is hermetically sealed to the wall of the container 62 by a seal 66, suitably of Teflon, thus forming an anode gas chamber 68 which is provided with a return conduit 70. The cell also includes a cathode 72 of tubular form with its inner end closed and disposed within the anode 64. The anode is preferably constructed of the same material as the cathode and both electrodes are formed as tubular membranes having a wall thickness of approximately five or six thousandths of an inch. The cathode defines a high-pressure gas chamber 74 and the outer end thereof is adapted for connection to a high-pressure supply conduit. A liquid electrolyte 76 is contained in the space between the cathode and anode and preferably comprises an aqueous solution of sodium hydroxide at high concentration' of approximately 80 weight percent. The electrolyte is sealed in the space between the electrodes by an annular seal 76, suitably of Teflon, disposed between the electrodes. The electrolytic cell is maintained at a desired operating temperature preferably approximately 200 C. by an electrical resistance heater 78 having its windings disposed within the container 62 and its electrical terminals extending through the wall thereof. The operating voltage for the electrolytic cell is provided by a voltage source 80 having its negative terminal connected to the cathode and its positive terminal connected to the anode, the applied volta e being preferably in the vicinity of one-tenth of a volt.

In the operation of the electrolytic cell in a hydrogen-pumping mode, the anode gas chamber 68 is charged with hydrogen gas from a suitable source of supply and the cathode gas chamber 74 is connected through a conduit to the desired load device and flow restrictor and the cell is operated until a 'desired charge of hydrogen has been assumed from the external source. Then the external source may be disconnected and the return conduit 70 may be reconnected to the exhaust conduit from the load device. Continued operation of the cell thus provides recirculation of the hydrogen gas from the high-pressure cathode gas chamber 74 through the load device and back through the exhaust conduit to the low-pressure anode chamber 63. In this mode of operation superatmospheric hydrogen pressure is developed in the cathode chamber 74 and subatmospheric pressure is developed in the anode chamber 68.

i.e., the rate of hydrogen It will now be appreciated that a single electrolytic cell 60' could be designed and adapted as the hydrogen pump for the operation of a load device. However, the gas flow requirements for a hydrostatic bearing in a laser scanner are of such magnitude in relation to the current requirements for the electrolytic cell that a preferred system design utilizes a plurality of electrolytic cells 60 to constitute the electrochemical pump 12. The arrangement and interconnection of the cells is shown in FIGS. 3 and 4. Referring first to FIG. 3, a bank 81 of cells comprises a sealed housing 82 which is divided by a header or wall 84 into a low-pressure anode chamber 86 and a high-pressure cathode chamber 88. A plurality of electrolytic cells 60' and 60" of the type described with reference to FIG. -2 are disposed within the housing 82 and mounted on the wall 84. It is noted that the electrolytic cells 60' and 60" within the bank of cells are connected in electrical series with each other across the voltage source, i.e., the anode of cell 60' connected to the positive terminal of the voltage source and the cathode is connected to the anode of the cell 60 while the cathode of the latter is returned to the negative terminal of the voltage source. Such an arrangement enables the use of power supply having a supply voltage greater than that required by each individual cell and determined by the number of cells connected in series in each bank. It is further noted that all of the cells within the bank have the fluid circuits connected in parallel with a common low-pressure anode chamber 86 having a return conduit 90. All of the cells have a common high-pressure cathode chamber 88 connected to a supply conduit 92. The cells are suitably maintained at the desired operating temperature by the respective resistance heaters 78' and 78".

As illustrated in FIG. 4, a plurality of cell banks of the type shown in FIG. 3 are connected together to form the electrochemical pump 12. In this arrangement the several cell banks have their electrical circuits connected in parallel and the gas fiow circuits are connected in parallel. Each

cell band

81, 81' and 81" respectively, connected through the

return conduits

90, 90' and 90" to a main return conduit 60 which is connected to the container 16 of the laser scanner [0, as shown in FIG. 1. Similarly, the high

pressure cathode chambers

88, 88' and 88", respectively, of the

cell banks

81, 81' and 81" are connected through

supply conduits

92, 92' and 92 to the main supply conduit 58 which is connected to the inlet passage 42 of the journal 40 in the laser scanner 10. With the electrical terminals of the

cell banks

81, 81' and 81 being connected in parallel across the voltage source, a failure, such as an open circuit in a single cell, will only disable the one particular cell bank.

The electrochemical pump 12, as just described, for supplying hydrogen pressure to the laser scanner is provided with a power source and control system 14, as indicated in FIG. 1. It is desired to operate the pump 12 so as to obtain a substantially constant pressure differential across the journal of the gas bearing. The power source 94 is suitably an aircraft power supply of 24 volt alternating current at a frequency of 400 Hertz. The output of the power source is supplied through a transfonner 96 to obtain a desired decrease in the alternating current voltage. The output of the transfonner is applied across a full-wave bridge rectifier 100 to develop a DC voltage across its output terminals, on

conductors

102 and 104, which are connected with the cell banks and individual cells, as indicated in FIGS. 3 and 4. The rectifier 100 is suitably of the type employing silicon-controlled rectifiers with a switching circuit whereby the conduction angle thereof may be controlled to regulate the average value of the output current. For this purpose the control system includes a modulator 106 adapted to control the switching angle of the silicon-con trolled rectifier devices in the rectifier 100 in response to the pressure differential across the journal 40 in the laser scanner 10. A pressure switch 108 is connected at one side by a conduit 110 to the high-pressure supply conduit 58 and is connected at its other side by a conduit 112 to the low-pressure or exhaust conduit 60. When the pressure differential increases to an excessive value, as sensed by the pressure switch 108, the modulator 106 is effective to reduce the conduction angle in the rectifier and thereby reduce the magnitude of'the current through the electrolytic cells. Similarly, as the pressure differential decreases below the desired value the modulator and rectifier are efi'ective to increase the current through the electrolytic cells and thereby increase the pressure. A trap 116, such as a molecular sieve, may be connected in the return conduit 60 to remove any contaminants in the gas such as hydrocarbons or amines that may be introduced by the motor or other such source. Thus, there is less likelihood of deleterious efiects on the hydrogen transmission at the cathode of the cell. The heater 118 with its associated thermostatic control 1 may be connected to the secondary of the transformer 96 to maintain the pump 12 at the desired operating temperature.

Although the description of this invention has been given with respect to a particular embodiment thereof, it is not to be construed in a limiting sense. Many variations and modifications within the spirit of the invention will now occur to those skilled in the art. For a definition of the invention reference is made to the appended claims.

The embodiments of the invention in which we claim an exclusive property or privilege are defined as follows:

l. The process of operating a hydrostatic gas bearing com prising the steps of; generating a 'gas flow by means of an electrolytic gas cell, restricting the flow of gas to produce a relatively high-pressure gas fiow, and supplying the high-pressure gas fiow to the inlet passage of the bearing.

2. The process of supplying hydrogen gas under pressure to a hydrostatic gas bearing comprising the steps of; generating a fiow of hydrogen through a hydrogen diffusion cathode in an electrolytic cell, restricting the flow of hydrogen emitted from said cathode to produce a high pressure and supplying the high-pressure hydrogen to the inlet passage of the bearing.

3. The process of supplying hydrogen gas at high steady pressure to a hydrostatic gas bearing comprising the steps of; generating a flow of hydrogen in an electrolytic cell of the type including a hydrogen diffusion anodic electrode and a hydrogen diffusion cathodic electrode with a gas chamber on one side of each electrode and a liquid electrolyte on the other side of each electrode, charging said gas chambers with hydrogen gas, applying a voltage across said electrodes and circulating the hydrogen gas diffused through the cathodic electrode through the gas bearing to the anode.

4. The process of supplying pure hydrogen at high steady pressure to a hydrostatic gas bearing of a load device in a sealed container and having an inlet passage connected to the journal of the gas bearing and an outlet passage from the journal to said container, said process comprising the steps of; generating a flow of hydrogen in an electrolytic cell of the type including a hydrogen diffusion anodic electrode and a hydrogen diffusion cathodic electrode with a gas chamber on one side of each electrode and a liquid electrolyte on the other side of each electrode, charging said gas chambers with hydrogen gas, applying a voltage across said electrodes, circulating the hydrogen gas from the cathodic electrode through said gas bearing to the anodic electrode with sufficient flow restriction in the external flow path of said hydrogen to produce superatmospheric pressure in the inlet passage of said bearing and subatmospheric pressure in the outlet passage thereof and in said container.

5. The invention as defined in claim 4 including the step of modulating the current'fiow between said electrodes to obtain substantially constant pressure-differential between said inlet and outlet passages of said bearing.

6. in combination with a load device having a hydrostatic gas bearing with supply and exhaust passages, an electrolytic cell including anodic and cathodic electrodes with an electrolyte therebetween, a voltage source connected between the electrodes, means for collecting the gas evolved at one of said electrodes, and means for conveying said gas to the supply passage of said bearing. 7

7. The invention as defined in claim 6 wherein said gas is hydrogen evolved at said cathodic electrode.

I. The invention a defined in claim I wherein said means for collecting is a chamber having a wall portion fonned by the cathodic electrode, the cathodic electrode being adapted to transmit hydrogen by diffusion from one surface to the other.

9. The invention as defined in claim 8 wherein said cathodic electrode is a solid metal alloy of palladium and silver.

10. The invention as defined in claim 9 wherein said cathode is tubular with one end closed and the other end connected to said supply passage.

11. In combination with a load device having a hydrostatic gas bearing with supply and exhaust passages, an electrolytic cell including anodic and cathodic electrodes with an electrolyte therebetween, a voltage source connected between the electrodes, each of said electrodes being in the form of a membrane and of a material adapted to transmit hydrogen by diffusion from one of its surfaces to the other, said cell including a low-pressure inlet chamber having a wall portion formed by the anodic electrode, a high-pressure outlet chamber having a wall portion formed by the cathodic electrode, hydrogen gas in said chambers, a conduit connecting said high-pressure chamber to the supply passage of said bearing and a conduit connecting said exhaust passage of said bearing to the lowpressure chamber of said cell.

12. The invention as defined in claim I] wherein both of said electrodes are constructed of a solid metal alloy of palladium and silver.

13. The invention as defined in claim 12 Wherein both of said electrodes are tubular and one is disposed inside the other.

14. The invention as defined in claim 11 including pressure responsive means connected with at least one of said chambers and with said voltage course and adapted to vary the current flow through the cell in accordance with said pressure changes.

15. The invention as defined in claim 14 including heating means adapted to maintain the cell at substantially constant temperature.

16. In combination a load device including a hydrostatic gas bearing within a sealed container, the bearing having an inlet passage connected with the journal of the bearing and an outlet pasage from the journal to the container, an electrolytic cell including anodic and cathodic electrodes with an electrolyte therebetween, a voltage source connected between the electrodes, each of said electrodes being in the town of a membrane and of a material adapted to transmit hydrogen by diffusion from one of its surfaces to the other, said cell including a low-pressure inlet chamber having a wall portion formed by the anodic electrode, a high-pressure outlet chamber having a wall portion formed by the cathodic electrode, hydrogen gas in said chamber, a conduit connecting said high-pressure chamber to the inlet passage and a conduit connecting the container to the low-pressure chamber of said cell.

17. The invention as defined inclaim 16 wherein said electrodes are constructed of a solid metal alloy of palladium and silver.

18. The invention as defined in claim 17 wherein said cathodic electrode is tubular with one end closed and the other end connected to said inlet passage.

19, The invention as defined in claim 16 wherein both of said electrodes are tubular and one is disposed inside the other.

20. The invention as defined in claim 16 including pressure responsive means connected with at least one of said chambers and with said voltage source and adapted to vary the current flow through the cell in accordance with pressure changes.

21. The invention as defined in claim 16 wherein both of said electrodes are composed of a palladium and silver alloy of about 25 percent and about 75 percent palladium and wherein said electrolyte is an aqueous solution of sodium hydroxide at a concentration of approximately weight percent of sodium hydroxide and wherein said cell is operated at a temperature of about 200C.

22. A load device having a hydrostatic gas bearing with supply and exhaust pauages, a plurality of electrolytic cells each having anodic and cathodic electrodes with an electrolyte therebetween, each of the electrodes being in the form of a membrane and of a material adapted to transmit hydrogen by diffusion from one of its surfaces to the other, a low-pressure inlet chamber, each of said cells having one side of its anodic electrode communicating with the inlet chamber, a high-pressure outlet chamber, each of said cellshaving one side of its cathodic electrode communicating with the outlet chamber, the high-pressure outlet chamber being connected with the supply passage of the bearing and the low-pressure inlet chamber being connected with an exhaust passage of the bearing, and voltage supply means connected with each of said cells whereby hydrogen gas is circulated through the bearing.

23. The invention as defined in claim 22 wherein the voltage supply means includes a voltage source with said cells being connected in series with each other across the voltage source.

24. The invention as defined in claim 22 wherein said plurality of cells includes first and second groups of cells, said voltage supply means includes a voltage source with the cells of each group being connected in series with each other across the voltage source and the first and second groups of cells being connected in parallel across the voltage source.

25. The invention as defined in claim 22 wherein said load device comprises a laser scanner in a sealed container and the low-pressure inlet chamber is connected with the exhaust passage of the bearing through said container whereby said container is evacuated to a low pressure thereby reducing the windage loss arising from high-speed rotation of said scanner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 586 435 Dated June 22 1971 I Carlo DelCarlo and Keith R. Jenkin It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, line 29 after "above" insert -adapted-. Column 5, line 36 bamT' should be --bank: line 37 after "81" insert --has its low

pressure anode chamber

86, 86' and 86",-. Column 8, line 17 after "25%" insert -silver.

Signed and sealed this 25th day of January 1972.

(SEAL) Attest:

EDWARD M.FLETCHER ,JR ROBERT Q CHALK Attasting Officer Commissioner of Patents FORM FWD-1050110459) uscoMM-Dc 6O376P69 U 5 GOVERNMENT PRINTNG OFFICE 7 i969 0*!66-334

Claims

2. The process of supplying hydrogen gas under pressure to a hydrostatic gas bearing comprising the steps of; generating a flow of hydrogen through a hydrogen diffusion cathode in an electrolytic cell, restricting the flow of hydrogen emitted from said cathode to produce a high pressure and supplying the high-pressure hydrogen to the inlet passage of the bearing.
3. The process of supplying hydrogen gas at high steady pressure to a hydrostatic gas bearing comprising the steps of; generating a flow of hydrogen in an electrolytic cell of the type including a hydrogen diffusion anodic electrode and a hydrogen diffusion cathodic electrode with a gas chamber on one side of each electrode and a liquid electrolyte on the other side of each electrode, charging said gas chambers with hydrogen gas, applying a voltage across said electrodes and circulating the hydrogen gas diffused through the cathodic electrode through the gas bearing to the anode.
4. The process of supplying pure hydrogen at high steady pressure to a hydrostatic gas bearing of a load device in a sealed container and having an inlet passage connected to the journal of the gas bearing and an outlet passage from the journal to said container, said process comprising the steps of; generating a flow of hydrogen in an electrolytic cell of the type including a hydrogen diffusion anodic electrode and a hydrogen diffusion cathodic electrode with a gas chamber on one side of each electrode and a liquid electrolyte on the other side of each electrode, charging said gas chambers with hydrogen gas, applying a voltage across said electrodes, circulating the hydrogen gas from the cathodic electrode through said gas bearing to the anodic electrode with sufficient flow restriction in the external flow path of said hydrogen to produce superatmospheric pressure in the inlet passage of said bearing and subatmospheric pressure in the outlet passage thereof and in said container.
5. The invention as defined in claim 4 including the step of modulating the current flow between said electrodes to obtain substantially constant pressure differential between said inlet and outlet passages of said bearing.
6. In combination with a load device having a hydrostatic gas bearing with supply and exhaust passages, an electrolytic cell including anodic and cathodic electrodes with an electrolyte therebetween, a voltage source connected between the electrodes, means for collecting the gas evolved at one of said electrodes, and means for conveying said gas to the supply passage of said bearing.
7. The invention as defined in claim 6 wherein said gas is hydrogen evolved at said cathodic electrode.
8. The invention as defined in claim 7 wherein said means for collecting is a chamber having a wall portion formed by the cathodic electrode, the cathodic electrode being adapted to transmit hydrogen by diffusion from one surface to the other.
9. The invention as defined in claim 8 wherein said cathodic electrode is a solid metal alloy of palladium and silver.
10. The invention as defined in claim 9 wherein said cathode is tubular with one end closed and the other end connected to said supply passage.
11. In combination with A load device having a hydrostatic gas bearing with supply and exhaust passages, an electrolytic cell including anodic and cathodic electrodes with an electrolyte therebetween, a voltage source connected between the electrodes, each of said electrodes being in the form of a membrane and of a material adapted to transmit hydrogen by diffusion from one of its surfaces to the other, said cell including a low-pressure inlet chamber having a wall portion formed by the anodic electrode, a high-pressure outlet chamber having a wall portion formed by the cathodic electrode, hydrogen gas in said chambers, a conduit connecting said high-pressure chamber to the supply passage of said bearing and a conduit connecting said exhaust passage of said bearing to the low-pressure chamber of said cell.
12. The invention as defined in claim 11 wherein both of said electrodes are constructed of a solid metal alloy of palladium and silver.
13. The invention as defined in claim 12 Wherein both of said electrodes are tubular and one is disposed inside the other.
14. The invention as defined in claim 11 including pressure responsive means connected with at least one of said chambers and with said voltage course and adapted to vary the current flow through the cell in accordance with said pressure changes.
15. The invention as defined in claim 14 including heating means adapted to maintain the cell at substantially constant temperature.
16. In combination a load device including a hydrostatic gas bearing within a sealed container, the bearing having an inlet passage connected with the journal of the bearing and an outlet passage from the journal to the container, an electrolytic cell including anodic and cathodic electrodes with an electrolyte therebetween, a voltage source connected between the electrodes, each of said electrodes being in the form of a membrane and of a material adapted to transmit hydrogen by diffusion from one of its surfaces to the other, said cell including a low-pressure inlet chamber having a wall portion formed by the anodic electrode, a high-pressure outlet chamber having a wall portion formed by the cathodic electrode, hydrogen gas in said chamber, a conduit connecting said high-pressure chamber to the inlet passage and a conduit connecting the container to the low-pressure chamber of said cell.
17. The invention as defined in claim 16 wherein said electrodes are constructed of a solid metal alloy of palladium and silver.
18. The invention as defined in claim 17 wherein said cathodic electrode is tubular with one end closed and the other end connected to said inlet passage. 19, The invention as defined in claim 16 wherein both of said electrodes are tubular and one is disposed inside the other.
20. The invention as defined in claim 16 including pressure responsive means connected with at least one of said chambers and with said voltage source and adapted to vary the current flow through the cell in accordance with pressure changes.
21. The invention as defined in claim 16 wherein both of said electrodes are composed of a palladium and silver alloy of about 25 percent and about 75 percent palladium and wherein said electrolyte is an aqueous solution of sodium hydroxide at a concentration of approximately 80 weight percent of sodium hydroxide and wherein said cell is operated at a temperature of about 200*C.
22. A load device having a hydrostatic gas bearing with supply and exhaust passages, a plurality of electrolytic cells each having anodic and cathodic electrodes with an electrolyte therebetween, each of the electrodes being in the form of a membrane and of a material adapted to transmit hydrogen by diffusion from one of its surfaces to the other, a low-pressure inlet chamber, each of said cells having one side of its anodic electrode communicating with the inlet chamber, a high-pressure outlet chamber, each of said cells having one side of its cathodic electrode communicating with the outlet chamber, the high-pressure outlet chamber being connected with the supply passage of the bearing and the low-pressure inlet chamber being connected with an exhaust passage of the bearing, and voltage supply means connected with each of said cells whereby hydrogen gas is circulated through the bearing.
23. The invention as defined in claim 22 wherein the voltage supply means includes a voltage source with said cells being connected in series with each other across the voltage source.
24. The invention as defined in claim 22 wherein said plurality of cells includes first and second groups of cells, said voltage supply means includes a voltage source with the cells of each group being connected in series with each other across the voltage source and the first and second groups of cells being connected in parallel across the voltage source.
25. The invention as defined in claim 22 wherein said load device comprises a laser scanner in a sealed container and the low-pressure inlet chamber is connected with the exhaust passage of the bearing through said container whereby said container is evacuated to a low pressure thereby reducing the windage loss arising from high-speed rotation of said scanner.