Abstract: A first compressor (10) supplies air under pressure to a first stage pressure swing adsorption system (D) which separates oxygen and argon from atmospheric air. A second stage pressure swing adsorption system (E) separates the oxygen from the argon. Each time the compressor (10) is shut off, pressure in molecular sieve beds (22a, 22b) and (90a, 90b) tend to equalize causing mixing of retained primary product gas a feed stock gas. When the compressor (10) is restarted, the intermixed gas is supplied with the primary product gas for the first few cycles. During the first few cycles, a diverter valve (130) diverts the primary product gas to a vent (132) such that the reduced purity primary product gas is not supplied downstream. Thereafter, primary product gas is drawn into a suction tank (110) which is maintained at a reduced pressure by a second compressor (112).

Abstract: A first separation stage (A) separates nitrogen, carbon dioxide, and water vapor from atmospheric air. A mixture of oxygen and argon is passed from the first separation stage as the feed stock to a second separation stage (B). The second separation stage includes a pair of molecular sieve beds (90a, 90b) which adsorb oxygen and pass argon. The feed stock is passed to one of the beds such that the oxygen is adsorbed and the argon flows through to an argon discharge port (96). When the first bed is reaching saturation, a secondary product valve (108) closes the argon discharge port, a flush valve (82) supplies high purity oxygen to the bed, and a product conservation valve (104) causes the oxygen and argon gas in the interstitial voids of the saturated bed to be channeled to the other bed. The other bed is at reduced pressure by virtue of having just had its adsorbed oxygen desorbed.

Abstract: A lift assembly adapted for large vehicles includes first and second lift platforms selectively raised and lowered relative to a base member. Fluid actuated support arms are interposed between the lift platforms and the base member to define a generally trapezoidal arrangement. Segmented bearings are interposed between opposite ends of the support arms and the lift platforms and base member to accommodate tolerance stackup. The lift assembly also includes a sensing assembly that determines if a height differential exists between the lift platforms. If a height differential is sensed, movement of one of the lift platforms is altered to correct the situation. If too great a differential is sensed, further movement of the platforms is terminated. A locking arrangement maintains the lift platforms elevated relative to the base member. A sensing arrangement determines whether the locking arrangement is properly oriented and whether the load is applied from the lift platforms.

Abstract: A lift assembly includes four swing arms interconnecting a base member and lift platform. A hydraulic cylinder selectively elevates the lift platform relative to the base member. A stiff leg also extends between the base member and the lift platform and cooperates with a series of stop blocks for locking the lift platform at predetermined heights above the base member. A link is associated with the stiff leg to selectively support the stiff leg above the stop blocks and permit an operator to move the lift platform between the predetermined heights. The link automatically positions the stiff leg for engagement with the stop blocks if the direction of movement of the platform is altered.

Abstract: Improved operating efficiency is achieved in a PSA gas concentrator by connecting the primary product gas outlet end of a pressurized sieve bed with a gaseous mixture receiving end of a second molecular sieve bed between each pressure reversal portion of a PSA gas separation cycle. A cross over valve (12) has a first mode (12a) in which a first bed (16) is connected to a source (10) of pressurized air and a second bed (18) is connected with an exhaust port (14), a second mode (12b) in which the second bed is connected with the source of pressurized air and the first bed is connected with the exhaust port, and a third mode (12c) in which the passage of gas between the pressurized air source, the exhaust port, and the first and second beds is prohibited. Check valves (50a, 50b, 50c, and 50d) and a pressure equalization valve (52) selectively interconnect second ends (22, 26) of one bed with the first ends (20, 24 ) of the other.

Abstract: A valve assembly (B) cycles compressed gas from a compressor (A) to a pair of molecular sieve beds (C) to perform a pressure swing adsorption gas separation cycle. Each bed includes a peripheral outer wall (20) and has a tubular member (30) extending down a central axis thereof. An extensible sleeve (26) surrounds the central tube and is in fluid communication therewith by way of an aperture (32). A fluid amplifier (F) amplifies fluid pressure from system gases, particularly the gases from the compressor, and uses the amplified pressure to expand the extensible sleeve. Particles (22) of zeolite material are inhibited from becoming fluidized and moving with fluid flows by the clamping pressure between the extensible sleeve and the peripheral wall of the bed.

Abstract: A fluid operated circuit for controlling the movement of pistons contained in the drive and idler cylinders of a conventional dual post vehicle lift assembly of the type wherein the cylinders are hydraulically connected in tandem so that movement of the idler cylinder piston is dependent upon movement of the drive cylinder piston and wherein the pistons, while operative to lift and lower movable article supporting structures, are not fixedly connected thereto.

Abstract: A cross over valve (46) cyclically supplies air from a compressor (30) to a first bed (48). The first bed contains a material, such as a 5 angstrom zeolite, which preferentially adsorbs nitrogen and passes oxygen and argon therethrough. The oxygen and argon mixture is passed to an oxygen/argon receiving reservoir (60). As the cross over valve flushes nitrogen from the first bed, a pumping fluid under pressure is fed into a pressurizing fluid receiving region (66) to pump the oxygen/argon mixture into a second bed (80). The second bed contains a material, such as 4 angstrom zeolite, which passes nitrogen and argon therethrough and which preferentially adsorbs oxygen. The argon, and the nitrogen if any, are discharged through a secondary gas outlet (22) and the oxygen is adsorbed. The adsorbed oxygen is drawn from the second bed by an enriched oxygen pump (90) and pumped periodically into an enriched oxygen storage reservoir (100).

Abstract: A compressor (10) and an accumulator tank (12) supply compressed air to an oxygen concentrator (32). Separated oxygen flows through a first check valve (40) into a first oxygen receiving region (54) of a first tank (50) displacing a first movable barrier (52). When a pressure sensor (72) senses that the pressure in the first oxygen receiving region has reached a preselected level, it causes a valve (62) to move from a vent state to a state in which compressed air is supplied from the accumulator into a pressurizing fluid receiving region (56). This displaces the first movable barrier with a first preselected pressure, pumping the oxygen through a second check valve (80) into a second oxygen receiving region (94) of a second tank (90). A second movable barrier (92) separates the second oxygen receiving region from a second pressurizing fluid receiving region (96).

Abstract: A cross-over valve (24) alternately supplies compressed air from a source of compressed air (A) to a pair of beds (26, 28) filled with a molecular sieve material. An oxygen rich gas component separated from the compressed air by the molecular sieve beds is channeled to a separated gas reservoir (C). To use the oxygen in the reservoir, the compressed air is directed against a barrier, such as bellows (52), located within the separated gas reservoir to compress the oxygen rich gas component held therein. The oxygen rich gas component is then supplied at this elevated pressure to welding or other downstream equipment. In this manner, the oxygen separator may operate sixteen hours to provide a supply of oxygen for an eight hour shift. The oxygen is supplied to the downstream equipment at a higher pressure which is increased over and above the supply pressure from the oxygen separation device.

Abstract: A gas fractioning apparatus includes a housing (A) in which various gas separation components and modules are located. A gas distribution module (B) which includes components for handling and distributing incoming gas to be separated is mechanically mountable within the housing. A control module (C) which includes the appropriate control components for controlling the gas separation is similarly mountable within the housing. An oxygen outlet assembly (D) which includes the fluid handling components for handling the separated oxygen is mounted with the control module in the housing. A bed module (E) which physically separates oxygen from other air components is mechanically mountable within the housing. A mechanical mounting assembly (F) removably mounts the modules within the housing. An electrical connection assembly (G) provides electrical connection between the electrical components of at least the control and distribution modules.

Abstract: A first compressor (10) supplies atmospheric air or other gaseous mixtures to a crossover valve (20) at a first relatively low pressure, e.g., 15-18 psi. The crossover valve alternately supplies the atmospheric air to a first molecular sieve bed (22) and a second molecular sieve bed (24) while simultaneously permitting the other molecular sieve bed to discharge adsorbed gaseous components of atmospheric air through a waste gas discharge port (26). A second compressor (40) draws the oxygen which passes through the molecular sieve beds without being adsorbed through a restrictor (60) and a needle valve (62). The restrictor and needle valve are selected and adjusted such that an oxygen pressure of about 2-6 psi is maintained upstream of at least the needle valve. The second compressor increases the pressure of the oxygen to at least 45 psi and pumps it into a storage tank (46) from which it may be supplied to welding or other industrial equipment.

Abstract: A double post lift assembly is disclosed wherein each post contains a stationary hollow tube disposed around a hydraulic cylinder and a movable hollow tube disposed around and laterally spaced from the stationary tube. A hollow sleeve is disposed in the space between the stationary and movable tubes of each post and is attached to a lower end portion of the movable tube for movement therewith. A series of spacer blocks constructed of non-abrasive material is disposed in slots arranged in two rows around each sleeve, which blocks project inwardly of the sleeves into sliding engagement with a corresponding stationary tube. A carriage arm containing an adjustable article supporting pad is attached to the lower end of each of the movable tubes. The pads are pivotally attached to the arms so that they may rock through a vertical arc and the arms are adapted to swing through a horizontal arc as the arms lift a rear end portion of a vehicle partially supported thereon.

Abstract: A vehicle lift having two hydraulically operated lifting cylinders for adjusting the height of a pair of weight supporting carriages, and having a control system featuring a cable strung between the carriages for responding, through changes in tension, to a change in relative vertical displacement between the carriages to actuate a levered valve assembly for controlling the rate of fluid being supplied to or from each lifting cylinder to eliminate the change and restore the preferred relative displacement between the carriages. The control system deactivates the lifts and effects engagement of safety latches to lock the carriages in place in their respective frames to limit misalignment thereof in the event of a control system malfunction. A fluid shuttle valve having a perforated cylinder which is both rotatable and translatable within the valve body to control fluid flow to and from each lifting cylinder is also featured.

Abstract: A shower stall featuring wall panels joined together to form a three-sided enclosure and a pair of rigid elongated hand rail members attached to opposing ones of the wall panels and extending rearward within the stall to connect to the rear wall panel. An elongated brace is attached to the outside surface of the rear wall panel and extends at least partially across the same to interconnect through the rear wall panel to each of the hand rail members.