BE658075A - - Google Patents

Description

       

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  Motive force fluid transfer apparatus.



   The present invention relates to a pressurized motive force fluid transfer apparatus and, more particularly, to a new and improved pumping apparatus as well as to new and improved methods for maintaining a favorable operating temperature of such apparatus. .



   Hitherto, difficulties have been encountered in the design and construction of apparatus for transferring fluid to. motive force acting by pressure, in particular pumping apparatus which use the motive force produced by a motive device acting on a first material such as a pumping or driving liquid which in turn acts on a separating member. ration to move a second material, for example material

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 pumped as a fluid, placed on the other side of the separator.



   The construction parameters of these known pumping devices include auxiliary devices serving to recirculate the pumping liquid under the action of the pumping liquid driving device and to cool the pumping liquid.



   The auxiliary devices of these known pumping apparatuses serving to recirculate the pumping liquid under the action of the driving device are mainly intended to maintain the pumping liquid and the desired level of its pressure in the device during the periods in which the second material does not pass through the pump. Because otherwise, it would be necessary to restore the working pressure of the pumping liquid every time the second material is to be forced back into the pump.

   It should be noted that the time required to restore the pressure of the pumping liquid, each time the second material has to be delivered into the pump, is particularly disadvantageous for certain uses of the device, for example in the case of: spray painting apparatus operating intermittently.



   The recirculation of pumping liquid through the apparatus for this purpose results in a further disadvantage that the power demanded from the motive force source of the apparatus is higher during these periods of pumping liquid recirculation than during the periods or the second material passes through the pump.



   These driving force requirements are in fact increased during the recirculation because, during this period, the pressure of the pumping liquid in the pumping chamber is maximum and the power required to move the driving device of the pumping liquid. page against the action of this pressure is therefore maximum.



   Another disadvantage of the known pumping apparatus is that during this recirculation period, the temperatures of;

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 pumping liquid and parts of the apparatus increase detrimentally compared to the temperatures of the pumping liquid and apparatus during the periods when the second material is passing through the pump. However, the known pumping devices require auxiliary cooling devices such as large cooling tanks or heat exchangers into which the pumping liquid is bypassed during its recirculation cycle to cool the pumping liquid and parts. unit to maintain proper pump operating temperature.

   A large cooling tank is bulky and heavy, and the heat exchanger increases the motive power requirements of the apparatus unfavorably during the period of time, that is, during the period in which the second material is not. not pumped, where the pumping apparatus requires maximum driving force to maintain the desired pumping liquid pressures.



   The need to equip the known devices with these bulky and expensive auxiliary devices made the device unportable and, therefore, required its permanent installation (so that it can only be used in a fixed location. The disadvantage of a non-portable pumping apparatus for spray painting is therefore evident because the object (s) to be painted generally must be portable. However, some known apparatuses used for spray painting have been mounted on a truck for painting. make them mobile.

   But even in this case, it is not possible to use the device on a 115 volt circuit because the required amperage usually exceeds the safety limits of ordinary networks and higher voltages are not commonly. available in much of the world.



   By virtue of the present invention, the problems and difficulties of, inter alia, connected apparatus are avoided.

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 We have seen this in the development of portable pressure-acting motive-force fluid transfer apparatuses such as pumps which eliminate the auxiliary recirculation and cooling devices which were required with known apparatus.



   The apparatus of the invention utilizes a phenomenon of cavitation to maintain substantially uniform the temperature of the pumping liquid and associated parts of the apparatus during periods when the pump is not moving the second material as well as the temperature of the pumping liquid. pumping and associated parts of the pump during periods when the pump is moving the second material, and to minimize the driving force requirements of the pump during periods of cavitation in which the second material is not passing through the pump.



   According to the invention, the action of the motor device on the pumping liquid is used, during periods in which the second material does not pass through the pump, to produce a cavitation effect on the pumping liquid in the pumping chamber. pumping liquid. The parts of the pump associated with the pumping liquid have one general temperature when the pump moves the second material and another general temperature in the "stationary" state when the pump is not moving the second material. The phenomenon of cavitation is used according to the invention to maintain the temperature of these parts of the pump in the "stationary" state substantially equal to their operating temperature.

   The use of the cavitation phenomenon for this purpose is hereinafter referred to as "cavitation cooling".
During operation under cavitation, the pumping liquid is cyclically vaporized instantaneously (cavitation) and the vapor thus produced is subsequently condensed. This vaporization and condensation produced by cavitation

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 have the effect of cooling the pumping liquid and the parts of the pump by cavitation, in particular the parts which are in contact with the pumping liquid and the vapor. In addition, the use of the cavitation phenomenon makes it possible to decrease the driving force requirements of the pump during the cavitation of the pumping liquid when the second material does not pass through the pump, compared to the driving force requirements when the second. material passes through the pump.



   These energy requirements characteristic of the pumping apparatus constructed according to the invention distinguish the invention from the known apparatuses mentioned above in which the driving force requirements are maximum when the second material does not pass through the pump.



   This being the case, one of the objects of the present invention is to provide: a new and improved pressure-acting motive-force fluid transfer apparatus; an improved liquid driven apparatus for fluids; a new and improved spraying system for liquids such as paints and the like; a new and improved pumping apparatus; a new and improved portable pumping device; a new and improved high pressure pumping apparatus comprising a diaphragm and an entrained fluid valve operatively associated with the diaphragm and arranged to minimize the risk of damage to the diaphragm during operation at high pressure;

   a new and improved pumping apparatus comprising a diaphragm subjected on each side to balanced fluid pressures except when the diaphragm is at least in a limit position; a new and improved supply apparatus for pumping liquid from a compressed high pressure pump

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 ning a diaphragm essentially devoid of any leakage path? for high pressure pumping liquid, except to a source of the liquid; a high pressure pump comprising a diaphragm and a supply apparatus for the pumping liquid comprising a device for automatically purifying the supply of pumping liquid;

   a new and improved easily adjustable mechanical linkage to change the volumetric capacity of a diaphragm pump, so that the pump is capable of pumping fluids at different pressures and / or capacities with substantial energy consumption constant; a new and improved pressure-acting fluid transfer apparatus which utilizes the phenomenon of pumping fluid cavitation to maintain the temperature of the pumping liquid and associated parts of the pump at a desired level.



   Other objects and advantages of the invention reside in methods of driving and / or controlling the pumping apparatus of the invention.



   These objects and advantages of the invention as well as others will emerge from the description given below with reference to the accompanying drawings, in which: FIG. 1 is a schematic side elevational view of one embodiment of the invention; Fig. 2 is a longitudinal section of the end on the pump side of the embodiment of FIG. 1, on a larger scale; Fig. 3 is a detailed sectional view, on a larger scale, of an interior valve used in each embodiment; Fig. 4 is an end view of a pump piston; Fig. 5 is a section taken along line 5-5 of FIG. 4;

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 Fig. 6 is a section, on a larger scale, of a decompression valve used in the invention;

   Fig. 7 is a schematic view, partly in half-section, of another embodiment of the invention; Fig. 8 is a schematic view of an adjustable drive linkage suitable for use with each embodiment; Fig. 9 is a side elevational view of a preferred embodiment of the invention; Fig. 10 is a plan view of FIG. 9; Fig. 11 is a detailed sectional view of a check valve used in the embodiment of FIG. 9; Fig. 12 is a section taken substantially on line 12-12 of FIG. 10; Fig. 13 is a detailed sectional view of an inlet fitting under the pumped fluid; and, FIG. 14 is a detailed sectional view of a check valve for the pumped fluid.



   Cavitation phenomena are useful in each embodiment of the invention. Only a small amount of pumping or driving liquid is used compared to known diaphragm pumps in which heating of the pumping liquid poses serious liquid cooling problems. As the pumping liquids used in the apparatus of the invention are caused to vaporize and condense, the pumping liquid and parts of the pump remain at low temperatures although the pumping liquid is turned on. under high pressure when driving fluids at high pressures.



   The pumping apparatus constructed according to the invention is characterized in that it comprises several motive force limiting devices which operate in cooperation.

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   The first motive force limiting device comprises a motive device comprising a driving piston and using the phenomenon of cavitation of the driving liquid between its liquid and vapor phases to reduce the driving force.
Necessary to actuate the drive piston of the apparatus when the demand for driven or pumped fluid is very low or zero, i.e. when a second material does not pass through the pump while the piston of drive or the like remains in operation.



   The second motive force limiting device is in the form of a decalibrated one-way decompression valve and is particularly useful with paint guns operating intermittently or with similar devices, but is not limited to this use,
According to a feature of the invention, the device. pumping of the present invention is characterized in that it comprises a thermally conductive diaphragm with a thin profile carrying valves capable of cooperating with valve seats for the pumping liquid and the pumped fluid.

   When the flow rate of the pumped fluid in the pump is decreased or stopped, the valve. pumping liquid mounted on the diaphragm is automatically closed by the diaphragm which reaches a predetermined limit of its stroke in which the pumping liquid valve and the diaphragm are in contact with parts of the pump body including the seats valve.

   When the pumping valve reaches this limit position, the pressure of the hydraulic liquid and of the pumping liquid in the apparatus tends to rise above the pressure of the pumped medium. -
The second motive force limiting device which is in the form of a pre-calibrated one-way decompression valve. is capable of operating when the pressure of the pumping liquid reaches this increased value to remove pumping liquid from the corresponding chamber in an amount exceeding

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 the desired predetermined volume of liquid required while the apparatus is delivering the pumped fluid so that there is less volume in the pumping chamber in order to achieve the first motive force limiting function, as described further below. detail below.



   The first motive force limiting device also functions to replenish the pumping liquid which may escape around parts of the pump and which comprises one or more low pressure valves such as reed type or ball type valves, which can be opened by atmospheric pressure, for example. When the pumping liquid valve is closed in the limit position mentioned above, at the end of a movement of the diaphragm to admit the pumped liquid, the pressure in the pumping chamber opens by "depression" the valve. retention of pumping liquid.

   The check valve (s), when open, are in low pressure liquid communication with the drive liquid in the pumping chamber and with a liquid supply source to provide a small amount of liquid to the pump. reconstitution training in the pumping chamber. However, the apparatus can be designed to cause these vacuum valves to open during the intake displacement of the diaphragm.



   When the pump is designed to move a maximum volume of pumped fluid, the drive piston or the like is provided with a maximum stroke to reciprocate the diaphragm and the mounted pumped fluid valve. on the diaphragm between its two limit positions in each reciprocating stroke or each piston cycle.



  Drive fluid leaks are replenished at the end of the intake displacement of each cycle. The parts are preferably proportioned so that a small excess of make-up or reconstitution liquid is provided. So in the

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 . drive part of the cycle, the pressure relief valve limiting the driving force can release a small amount of liquid if - the pumped fluid valve, mentioned above, closes at the end of a drive part of a cycle ; however, in these circumstances, several successive cycles are performed at the maximum desired capacity and efficiency of the pump.



   It is presently preferred to construct pumps for use at maximum inherent capacity. However, it is not essential that this capacity be used and thus a lower capacity can be achieved while delivering entrained fluid under increased pressure.

   To change from a first volumetric capacity of the pump, for example at 5000 pounds / square inch (350 kg / cm2) to a second capacity substantially equal to half of the first but at 10,000 pounds / square inch (700 kg / cm2) cm2) or a third capacity equal to half of the second but 2000 pounds / square inch (140 kg / cm2), it is sufficient to change two parts of the pump to achieve these and other capacities while using the same motive force for driving the liquid in one embodiment of the invention. One part to be changed is the pressure relief valve limiting the driving force and the other is the piston drive linkage.



   In pumps with lower capacity but higher pressure, the amplitude of the diaphragm cycle is reduced. This cycle does not reach the two limits of a cycle mentioned above for the maximum amplitude. But it is important that the functions of supplying and discharging the driving liquid are ensured in order to achieve the aforementioned driving force limiting function and to prevent parts of the pump from being damaged during start-up. during operation and during normal operation because the displacement of the diaphragm may

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 intermittently reach either of the limits determined by the valve seats.



   Although the invention is applicable to many pressure vessels, the following description of the embodiment of FIG. 1 relates to an application using the invention in pumping equipment for an apparatus for supplying an intermittent spray gun. In a specific use of the apparatus for supplying an intermittently operated gun or the like, substantial savings in driving force are achieved when the gun is closed as a result of the vaporization and cyclic condensation of the spray liquid. training. The pumping liquid is cycled between its vapor and liquid phases by a new distribution device described in detail below.

   This cycling is prevented by the apparatus when the pump is conditioned to deliver pumped fluid under pressure in order to achieve high pumping efficiency.



   It is known that liquids are considered to be substantially perfectly elastic and practically incompressible. As an example only, a pressure of 1 pound per square inch (0.07 kg / cm2) compresses one part of ether to 120,000 parts, 1 part of water to 300,000 parts, and only 1 part of mercury to 4,700 .000 parts. Other liquids exhibit characteristic compression phenomena. It is preferable to use oil and kerosene, ethylene glycol, oil alone or a mixture of glycerin or alcohol with water in the pump described below.

   However, any known liquid exhibiting favorable non-corrosive characteristics and reversible liquid and vapor phases can be used within the framework of the invention. A pump uses a mixture of 4 parts SAE 5 oil and 1 part kerosene, and it is assumed

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 (although we are not sure) that only kerosene contributes significantly to the phenomenon of cavitation.



   Just as a specific example of the use of cavitation in a pump, a test device has been developed comprising a friction brake and a variably loaded lever apparatus. A commercially available 3/4 horsepower squirrel cage electric motor was coupled by a chain reduction gear to a connecting rod for driving a pump piston. The brake lever apparatus is designed to decelerate the motor by applying a weight intended to act at a point on the lever and the following interesting phenomena have been observed.



   With a drive oil liquid pump operative to feed a gun having a given size orifice and with a substantially uniform flow of water at a predetermined high pressure, it has been found that a substantially uniform force of 20 pounds (9 kg) applied to the lever point is necessary to brake and thus decelerate the engine.



   When the gun is closed and the pump is operating in the cavitation and condensation phases of the drive oil, a force of substantially 50 pounds (22.7 kg) is required to brake and thereby decelerate the motor. ..



     It is reasonable to assume that this latter force of 50 pounds (22.7 kg) can be considered representative of the maximum mechanical efficiency of the given engine so used.



   This being the case, depending on the size of the orifice used and the pressure of the liquid, etc., supplied to a gun or the like and depending on a suitable drive motor consuming little energy in the "stationary" state, one can achieve significant savings in motive power. The specific example above shows that it is possible to save at least 60% of the driving force consumption in most applications of the invention.

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   With regard to construction details, reference is first made to FIG. 1 in which a preliminary pump construction indicated at 10 is shown schematically as being attached to a suitable surface 12 such as a web of a channel or an I-joist or the like, which is strong enough to react to stress. relatively high forces while not allowing any appreciable displacement of the various parts of the apparatus which will be described.



   The pump 10 is fixed on its left side to the surface 12 by a plate 18 welded to end brackets 19 of which only one is shown which are in turn bolted by bolts 20 on the. surface 12.



   The pump is intended to pump material from a source of material 14, this material being supplied through a line 15 to one side of a pumping diaphragm described below.



  A device 16 using the material, which may be of any type such as a paint gun, receives fluid under high pressure through line 17 when it has been compressed by the pump. Although this figure does not show, an accumulator may be desirable to decrease pressure changes due to the intermittent action of a small number of correspondingly driven pistons and diaphragms.



  Of course, several pistons can be used in a known manner to provide a high, substantially continuous pressure. if desired.



   Pump 10 comprises a body formed from two halves 22 which may be substantially identical as shown in the drawings, in many applications of pump 10. A thick-walled pump cylinder 24 cooperates with a piston 25 driven therein by. a rod 26 coupled to a relatively bulky conventional piston 29 contained in the body 30 of the

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 hydraulic motor 28.

   The hydraulic motor 28 is driven in a reciprocating motion by hydraulic fluid pressurized by a. suitable engine oil compressor 32 or the like which introduces and discharges oil respectively through lines indicated schematically at 33 and 34 '. When the piston 25 is single-acting, the piston 29 can be resiliently biased towards the straight line and only one hydraulic line 34 must then be used, in a known manner.



   When the piston is double-acting, the introduction of high pressure oil into line 33 pushes piston 29 to the right and the discharged oil passes through line 34 to a collection, not shown, in hydraulic compressor 32 When high pressure oil is supplied through line 34, piston 29 is pushed to the left and the return oil returns through line 33 to hydraulic compressor manifold 32. Hydraulic motor 28 is suitably. fixed to the surface 12 by a conventional construction, not shown.



   To control the reciprocating motion of piston 29 and the corresponding reciprocating motion of piston 25 in cylinder 24, a switching mechanism 35 can be used.



  As the drawing shows schematically, a switch 36 is actuated in one direction or the other by a cradle 37 mounted on an actuating rod in the form of a pivot 38 and comprising actuating arms 39 and 39a. Two adjustable flanges 40 and 40a can be spaced from the position shown between resilient stop rings 41 and 4la 'to modify the length of the stroke of the pistons 29 and 25; in the position of the flanges 40 and 40a shown, the pistons 25 and 29 have a maximum stroke.

   When the switch mechanism 35 is moved to the left, the flange 40a contacts the arm 39a to reverse the switch 36 which through a line 43 can switch solenoid valves or the like.

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 and the hydraulic compressor 32 can then deliver high pressure oil through the line 33 to reverse the course of the piston 29 until the flange 40 comes into contact with the arm 39 to connect the line 33 to the manifold and deliver high pressure oil through line 34 to move piston 29 again to the right, i.e. in the compression stroke of piston 25, as described in detail below.



   Oil or ethylene glycol or other suitable liquid is contained in a reservoir 45 which may be of relatively small volumetric capacity. For example, with a piston 25 of 1 inch (2.5 cm) in diameter, it was found that in substance a quarter (0.946 liters of liquid is sufficient when the ipiston 25 moves in a reciprocating motion at the rate of about 1700 strokes of 1/2 inch (1.27 cm) per minute These figures are given by way of example only and the invention contemplates the use of higher and lower reciprocating speeds as well as dimensions and different stroke values which may be desirable for different uses of the pump.

   The drive liquid 46 is introduced through a tube 47 inside the cylinder 24 by a construction described below. The interior of the reservoir 45 communicates with the atmospheric pressure through a tube 48 connected to a filter 49 having a cap 50 serving to prevent dust and foreign bodies from entering the reservoir 45.



  A filter mesh 46 is also provided in the reservoir 45 to further ensure the cleanliness of the drive liquid.



   In Fig.2, the line 15 coming from the material source is connected to a double check valve 52, comprising. both an inlet retaining ball 53 and an outlet retaining ball 54 connected to the pipe 17 leading to the material utilization device 16, fig.l. The fluid to be pumped passes through the check valve 53 and through a fitting 55

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 into a lumen 56 and enters a pumping chamber 58 formed in the left half 22 of the diaphragm pump 10 and bounded by a diaphragm 60 fixed between the two halves 22.



   Suitable high strength fasteners such as bolts 23 screwed into nuts 23a secure the pump halves 22 against each other at their contact faces 22a, the bolts 23 having undergone maximum tension. predetermined to prevent the faces 22a from separating.



   The lumen 56 has a taut, preferably planar face 62 of diameter at least slightly less than that of a valve 63 which is preferably planar on its left face to cooperate with the surface 62 to close the lumen 56 in a manner. described in detail below.



   The pumping liquid enters a pumping chamber 65 on the opposite side of the diaphragm 60 and this liquid is introduced through a lumen 66 through a fitting 67 which fixes the cylinder 24 of the pump to the right outer face of the right half 22 of the pump. diaphragm pump 10. A gasket 68 of copper or other suitable sealing material is preferably provided between a planar face 70 at the end of cylinder 24 and bears on the surface of half 22 of the pump. .



   A planar face valve 73 cooperates with a planar surface 74 to close the lumen 66. When either aperture 56 or 66 is closed in the presence of the high pressure pumping liquid or the pressurized pumped fluid, the diaphragm 60 yields elastically around the rounded or chamfered edges 63a and 73a of the valves 63 and 73 respectively and is therefore not damaged * The diaphragm 60 can therefore be very thin and a polypropylene sheet thickness of between 20 and 40 thousandths of an inch (0.5 and 1 mm) has been used successfully without successively slicking the diaphragms.

   Of course, other plastics can be used and the desired characteristic is that the plastics material is tough.

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 in the presence of high pressure and corrosive materials, some of which may be substantially heated before passing through the pump to achieve the desired fluidity, for example. As a specific example, the pump of the invention may be used for pumping paints or the like which contain certain highly corrosive solvents and therefore other plastics than those mentioned above may be of more interest.

   For example, plastics such as "Mylar" of different thicknesses have been used successfully in such applications.



   The piston 25 is only shown schematically in Fig.2 and will be described in more detail with reference to Figs.4 and 5. A high pressure decompression valve 75 serving to allow the passage of pumping liquid from the chamber 77 to a low pressure chamber 78 located on the other side of the piston 25 is secured in the piston 25 in this embodiment of the invention. A supply valve. 80 is shown in the form of a reed valve 80 on the face of the piston 25 and also communicates with the chamber 78. The chamber 78 is closed by a sleeve 81 containing O-rings 82 ensuring the liquid tightness of the valve. rod 26 and an extension sleeve 82 which has the shape of a pipe end. The sleeve 81 is suitably fixed by an elastic stop ring 83.



   The extension sleeve 82 carries a weld saddle 85 in which a tube 86 is engaged, this tube 86 communicating with a tee 87 connected to a check valve 88 intended to receive fluid from the chamber 78 and to expel it into the tube. reservoir 45 and an inlet check valve 89 for admitting liquid into chamber 78. When piston 25 moves back and forth and first to the right,: the

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 liquid contained in chamber 78 is discharged through tube 86 and through check valve 88 into reservoir 45. As piston 25 is moved to the left, liquid is drawn through check valve 89 ;, the tee 87 and tube 86 in chamber 78.



  A filter mesh 90 is supported on a bulkhead 92 by a nut 93 screwed onto a threaded rod. The mesh 90 fits tightly around an interior bead 95 so that liquid in reservoir 45 rises through the channel. right half of the mesh 90, then descends through the left half of the mesh to return to the chamber 78 in the sleeve 82. However, any foreign matter present in the system is discharged through the check valve 88 and can be discharged periodically. by a drain plug 97.



   Fig. 3 shows a detailed sectional view of the inner valve of the pump serving to control cavitation and condensation and to strengthen the center of diaphragm 60. The valves 63 and 73 are preferably pressed against the diaphragm 60 which is shown in excess pressure. its central part 60a.



  A rivet having a head 100 is passed through a ring 101 and its end 102 is riveted against the ring 101 so that the two faces of the valves 63 and 73 have substantially the same shape and the diaphragm cannot be accidentally fitted. 'improperly in the construction shown in Fig. 2, for example. The head 100 and the riveted end 102 are sufficiently smaller than the ports 56 and 66 to be able to pass through these ports and not to interfere with the application of the valves 63 and 73 against their seats, that is to say lights 56 and 66 respectively.



   Figs. 4,5 and 6 show construction details of piston 25, high pressure relief valve 75, and reed valves 80. Face 105 of piston 25 is preferably planar and contains at least one. reed valve 80

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 serving to admit liquid at low pressure from chamber 78 into chamber 77 in cylinder 24 of the pump. Depending on the dimensions of the piston 25 it is desirable to provide several valves 80 and in this case three such valves are shown. Each valve 80 covers a small orifice 106 communicating with a passage 107 parallel to the axis of the piston in connection with a countersunk groove 108 through which pumping liquid can pass to the orifice 106.

   The valves 80 are fixed to the face 105 of the piston 25, for example by small screws 110 or rivets or the like, in a well known manner.



  The stress which closes these valves is very low so that the atmospheric pressure and the resistance to opening of the check valve 88 are sufficient to open the intake ports 106 to introduce a very small amount of driving liquid into the valve. chamber 77, Fig. 2, during a stroke of the pump.



   Piston 25 includes a number of O-rings 112 or the like which keep leakage around the piston to a practical minimum. Three O-rings are shown in Fig. S and this number can be decreased or increased for different pump operations. Leaks around these O-rings are essentially the only leaks that occur during operation of the pump. pump at normal capacity and they are often very light for a few strokes of the piston 25.

   But, after several strokes, the leaks may be sufficient for the valve 73 to come. close the port 66, Fig. 2 and consequently the pressure of the pumping liquid in the chamber 77 is decreased at the right end of the stroke of the piston 85 and opens the reed valve (s) 80 to introduce a small quantity of pumping liquid in chamber 77 in order to maintain this chamber at a substantially constant volume for a capacity of

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 positive displacement pumping and normal desired efficiency of the diaphragm pump 10.



   The decompression valve 75 is shown in the center of the piston 25. The valve 75 is essentially in the form of a tube and may advantageously be made of a thick-walled tube preferably having a laminated thread 114 which is formed on it. the tube substantially in the middle of the valve 75. The valve 75 has grooves at its ends 115 and 116 and contains a transverse notch 118 intended to engage with a suitable tool for screwing the decompression valve 75 in place by its two ends to one end described below with reference to Fig. 7. One of the ends 115 and 116 may receive O-rings 119 depending on which of these ends is introduced into the piston 25 or anywhere else.



   The decompression valve 75, shown in Fig. 5 is introduced into the piston 25 with its threaded part 114 screwed into the center of the piston 25. The straight O-rings 119 seal the inner end 116 of the piston. the valve 75 in an axial bore of the piston 25. High-pressure liquid can pass through a passage 120 in a passage 121 formed in the rod 26 and can exit through a transverse bore 122 communicating with the chamber 121. A sealing cap 123 is secured by a resilient snap ring 124 to prevent oil from entering the hollow center 125 of rod 26 which is recessed to minimize the weight and machining operations required to secure piston 25 to the shaft. rod 26, this fixing being carried out advantageously by threads 127.



   As shown in Fig. 6, the pressure relief valve 75 includes a valve seat 130 having a lumen 131 substantially 3/32 inch (2.38 mm) in diameter in this particular embodiment. An elastic stop ring 132 fixes the seat 130 in place against the bias of the springs 135 136 130 in place against the bias of the springs 135 and 136

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 which bias a ball 138 of about 1/8 inch (3.2 mm) in diameter, for example, in contact with seat 130 which may be 3/32 inch (2.38 mm) in diameter. The ball 138 and the valve seat 130 are preferably made of high abrasion resistant steel or ceramic or the like so as to exhibit good wear characteristics for intermittent valve operation.

   The ball 138 is guided by a shoe 140 connected to a valve stem 142 guided in turn in a slot 143 formed in a threaded plug 145 serving to adjust the bias of the springs. With this construction and arrangement, the section of lumen 131 determines the pressure at which a ball 138 allows high pressure liquids to pass from chamber 77 into chamber 78, Fig. 2.



   The threaded plug 145 has a groove or notch 148 whereby it can be clamped against the springs 135 and 136 to adjust the decompression pressure determining the displacement of the valve 138. Using the left O-rings 11.9, the valve can be inserted. 75 in an adjustment device subjected to the pressure of the fluid and the screw cap 145 can be tightened until the valve 138 closes against the action of this pressure. Then, the threads adjacent to the threaded plug 148 can be hammered to fix this setting permanently.



  Precisely preset valves 75 are thus obtained without any difficulty.



   Springs 135 and / or 136 are not necessarily very powerful. For example, with a lumen 131 diameter of about 3/32 inch (2.38 mm) it only takes 5 pounds (2.3 kg) of force or resilient bias acting to the left in Fig. 6 to balance a pressure in the lumen 131 of the valve at 1000 pounds per square inch (70 kg / cm2). Thus, an elastic load of about 35 pounds (15.9 kg) can counterbalance a liquid pressure of 5000 pounds, (350 kg / cm2) and 50

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 pounds (22.7 kg) can offset 10,000 pounds (700 kg / cm2) etc.



   The valve 75 can also be used as a liquid supply valve by using one or more very weak springs instead of the springs 135 and 136. To use the valve 75 as a pumping liquid supply valve, one introduces causes this valve in the pistons 25 in the opposite direction to the position shown in Fig. 6 so that a low pressure existing in the chamber 77 may force the valve 138 to open to introduce pumping liquid into the chamber. room 77.



   A plug 150 Fig. 2, is used to evacuate the air from the chamber
77 but can also be used to introduce a valve,
75, if desired, so that the supply or discharge of the liquid into the chamber. 77 can be effected in a part external to the cylinder 24. This is particularly desirable where it is necessary to be able to easily change the pumping capacity. .



   In this case, the decompression valves 75 occupy the place of the plug 150 which can thus be easily interchanged and put in communication with the reservoir 45 so that the evacuated liquid is returned there, this return being able to be effected with connections of conventional plumbing. Of course, the pressure relief valve installed in place of the plug 150 is subjected to atmospheric pressure on its outlet face so that high pressure plumbing fixtures are not required outside the pump.



   PUMPING OPERATION
The liquid driven pump described above is intended, as shown in the drawings, to operate under high pressure, i.e. in pressure ranges of up to. thousands of pounds per square inch for example. Because of these desiderata, the drive rod 26 is of large diameter

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 to apply these high pressures. The walls of cylinder 24 and parts 22 of the pump are thick to withstand burst pressure and in particular sudden applied pressures such as may be encountered in liquid driven pumps.



   The embodiment described above may also include a conventional hydraulic drive motor 28 (Fig.l). This reciprocating motor 28 'may have fixed or variable strokes, for example a maximum stroke of 3 1. / 4 inches (8.26cm). The operating mechanism 35 can limit the stroke to limits equivalent to
3 1/4 inches (8.26cm) using adjusting rings 40 and 40a.



   - For the maximum stroke of 3 1/4 inches (8.26 cm), with a piston 29 of 3 inches (7.6 cm) in diameter, a pressure of 860 pounds per square inch (60.5 kg / cm2) in line 34 exerts a force of about 6,100 pounds (2,770 kg) on the right side of piston 29, neglecting friction losses, etc. The piston
25 in cylinder 24 exerts a force of substantially 6100 pounds (2770 kg) on the liquid to the left of the piston. When the piston
25 is 1 1/4 inch (3.2 cm) in diameter, the volumetric displacement of the piston in a 3 1/4 inch (8.26 cm) stroke is about 4 cubic inches (0 , 11 m3) by neglecting the compressibility of the liquid.

   The area of the face of the piston 25 is approximately 1.22 square inches (7.87 cm2) and the net pressure in pounds per square inch (kg / cm2) exerted on the liquid and on the fluid contained. naked in pump 10 is about 5000 (350). Cha. 58 and
65 should have a maximum total volume of about 4 cubic inches (0.11 m3) for this pumping capacity and this volume can be achieved with a diaphragm of about 4 inches (10.2 cm) in effective diameter having a maximum displacement of about 5/8 inch (15.9 mm) this diaphragm being disposed in retort substance as shown in FIG. 2.

 <Desc / Clms Page number 24>

 



   When smaller pumping volumes are desired, the adjusting rings 40 and 40a, Fig. 1. The rings, 40 and 40a are advantageously fixed by small stop screws, not shown, which can be loosened to move the rings 40 and 40a further apart. With this spacing, fingers 39 and 39a force hydraulic motor 28 to travel shorter strokes and piston 25 is therefore driven in correspondingly shortened strokes. The elastic stop rings 41 and 4la determine the adjustment limits for a minimum volumetric capacity of the pump 10 ..



   As described below with reference to Fig. 8, an adjustable mechanical linkage may be interposed between a source of motive force, such as an electric motor or the reciprocating hydraulic motor 28 and may include a crank or an alternating motor. of stroke determined for different stroke lengths of the drive piston 25 in the pump 10.



  In this case, it is preferable that the high pressure relief valve 75 is external to the sleeve 24 and is placed at the location of the ventilation plug 150, Fig. 2, for example.



  In this position, the pressure relief valve 75 can be replaced by a pressure relief valve operating at a higher pressure but shorter strokes of the piston 25, so that the pump 10 can be adjusted to operate at higher pressures. increased but at a lower volumetric capacity, these pressures being; determined by lecdispositif 16 which uses the material and limited by the decompression valve 75. However, a powerful engine! stationary can operate the pump at different volumetric capacities. and at different fluid pressures.



   Fig. 7 shows another variant of the invention indicated generally at 152. This variant is

 <Desc / Clms Page number 25>

 more particularly intended to operate at low pressures, for example pressures between 1000 and 2000 pounds per square inch (70 and 140 kg / cm2) although it can operate at higher or lower pressures with parts suitably designed for this effect.

   A paint gun or the like 153 is for receiving fluid from a source in the form of a reservoir 154 or the like which is subjected to a hydrostatic or other load suitable to operate the diaphragms 60 of the valves. pumps 10a and 10b which may be identical in this respect to the pump described with reference to Figs. 1 and 2 et seq., except that the controls are removed from the piston and cylinder in this embodiment for reasons which will become apparent more clearly below.



   The gun 153 can be any high pressure type commercially available and is shown as a gun having a valve body 155 and a spray nozzle 156 and a trigger 157 for actuating a valve 158. which cooperates with a valve lumen 159. The valve 158 can be resiliently biased towards its closed position and can be opened by a leftward pressure on the trigger 157.



   The fluid source 154 can be filled with paint and an appropriate solvent which can be discharged through a supply line 160 through either of two identical check valves 161 into either chamber. pumps not shown provided in the diaphragm pumps 10a and 10b by identical supply lines 162. As the diaphragms 60 are pushed down by the pressure of the pumping liquid contained in lines 165 and 166 respectively, the paint or similar material is discharged by one or other of the identical check valves 167 into a manifold 168 then

 <Desc / Clms Page number 26>

 by an accumulator 170 in a flexible supply pipe 171 connected to the gun 153.

   Accumulator 170 may be an air accumulator and has a liquid level 172 which can rise and fall to some extent between acceptable pressure variations, referred to in more detail below.



   The pump 152 is of the double-acting type and has a piston 175 reciprocally moved in a cylinder 176 by a piston rod 177 which passes through a suitably sealed plug 178. The piston and piston seals. plug 175 and 178 respectively have not been shown because they may be of the kind described above. Piston rod 177 is attached to a caliper 180 which in turn is hinged by a pivot 181 to a pivoting connecting rod 182. 183 on a crank 185 which can be driven by an electric motor directly or by means of a reduction mechanism not shown,

   when this reduction is desirable.A variable link to drive this embodiment of Fig.7 as well as the embodiment of Figs. 1 and 2 will be described below with reference to Fig.8.



   The piston 175 of the embodiment shown in Fig. 7, preferably has a relatively short reciprocating stroke. By way of non-limiting specific example, the piston 175 may have a section of about 1.5 square inches (9.7 cm2) and can be moved in a stroke of substantially 1/2 inch (1.27 cm) and thus have a capacity of 1/4 cubic inch (4.1 m3) of pumping liquid in both directions of reciprocating motion of the piston 175. It is understood that the section of the piston rod 177 must be subtracted from the volumetric capacity of the right-hand chamber 190 of the pump 152. But, the total necessary for a complete rotation of the crank 185 in this example can reach in substance 1/2 cubic inch (8.2 cm3).



     . At approximately 462 revolutions per minute, the volumetric capacity

 <Desc / Clms Page number 27>

 Maximum pump 152 is 231 cubic inches (0.0036 m3) per minute or approximately 1 US gallon (3.78 liters). This is quite a large amount for painting but is not excessive for cleaning or blowing semi-liquid plaster or the like.

   Lower capacities for the pump can advantageously be achieved by adjusting the piston 175 by means of a mechanical connection of a g @@ re described below with reference to Fig. 8 to decrease its cover from the maximum capacity.
 EMI27.1
 represe'VO on Yig.8. At c; t; <maximum capacity, it is preferable. set a decompression valve indicated at 192 so that it: 1 "operates at ur .: minimum release so as to prevent * -e mo,.:., from burning 1 1 'The pump 152 is set to deliver or a capacity i. ., m.



  The L. valve, -compression 192 p. , -xe of the type of the decompression valve, -represented and seen above with reference to i'ig.6 maib i valve is shown- adjustable in the schematic view of. "U'ig.7. dt4 pressure 192 is connected by a high pressure pipe 193 to a port 194 in communication with the end cable 195 of the pump 152. A ball valve 196 is biased by a spring 197 set by a plug 198 forming stop screw.



  A low pressure line 199 is connected to a liquid supply tank 200 in communication with atmospheric pressure, as explained with reference to Fig. 1, for example, or any other suitable construction.



  A check valve 192a identical to the check valve 192 may be provided. These check valves 192 and 192a are designed to open in the presence of high pressure in the liquid in chamber 190 and 195 to discharge liquid in reservoir 200. If, for example, the pump is operating. at 1000 pounds per square inch (70 kg / cm2) of pressure supplied, it may be desirable to adjust check valves 192 and 192a from

 <Desc / Clms Page number 28>

 so that they open to about 100 pounds above this value i.e. 1100 pounds per square inch of pressure (77 kg / cm2)

   so as to prevent unnecessary opening and closing of the ball valves as a result of small shocks that occur in the pumping liquid when the pump is operating at maximum pumping capacity or other desired pumping capacity, the gun 150 being open as well as the val @ e 158.



   Two low pressure check valves 202 and 202a deliver feed or reconstitution liquid in small amounts, for example as indicated by a drop 203 which is shown falling into chamber 195 and which is discharged by the valve.
202 when the piston 175 moves to the right, that is, when the gun 153 is closed. The check valve 202 can deliver a drop of liquid also when the plunger 175 moves to the left and when the gun is closed. The drops of liquid are dispensed at a rate sufficient to only take a few seconds to replenish the quantity. of driving fluid in chambers 190 and 195 when the gun
153 is operated to spray paint.

   When actuated, gun 153 initially receives spray fluid from the fluid reserve accumulated in accumulator 170 at the high fluid pressure level 172. It is preferred that the flow rate is of the drops 203 is such that the pressure of the accumulator does not drop substantially below that which is necessary to ensure proper spraying by means of the gun 153.

   When the gun valve 158 is opened for a short period of time, the piston contained in the pump 152 driven by the crank 183 (Fig. 7) begins to act on predetermined maximum amounts of liquid in the chambers 190 and 195 to provide positive drive of diaphragms 60 between desirable limits and can be set to act between limits different from the strokes of the pistons 175

 <Desc / Clms Page number 29>

 in walnut, the mechanical connection of FIG. 8 serving to adjust the displacement of diaphragms 60. Thus, displacement of diaphragms 60 replenishes the reserve of fluid in accumulator 170 and gun 153 is properly supplied as long as its valve 158 remains open.



   When the chambers 190 and 195 are filled with pumping liquid (not shown) ... the diaphragms 60 contained in the diaphragm pumps 10a and 10b are driven to a maximum stroke and each of them operates in substantially a manner. identical. For example, considering diaphragm 60 of pump 10a, with piston 175 moving to the left, diaphragm 60 is driven downward by pumping liquid moving through line 165. In addition, the fluid contained in the pump 10a on the underside of the diaphragm is forced downwards through the line 162., the check valve 167, the manifold 168, the accumulator 170 and the tube 171 towards the gun 153.

   At the same time, fluid is supplied from the fluid source 154 through line 160, right check valve 161, and line 162 to pump 10b. When the gun is opened successive cycles continue to supply pumped fluid to the gun 153 and there are sudden rises in the level of liquid 172 in the accumulator 170 to incorporate pulsations into fairly small pressure variations in the fluid. pump.



   CAVITATION OPERATION WHEN INSIALLATION
IS "STATIONARY".



   When the gun 153 is closed, that is, when the valve 158 closes the lumen 159, the following phenomenon occurs. The pressure of the fluid in the fluid source is such, either by gravity or by the pressure transmitted to the fluid, that it prevents cavitation in the inlet check valve 161 and in the various conduits connected to the ponpes. diaphragm 10a and 10b. However, when the

 <Desc / Clms Page number 30>

 
 EMI30.1
 J.1.7t $ 'Q) <i \ 4! <NJ * Q41v <4taa% <àli: mttr. '' 1 1, tl Ms' !! 4nm 5.., S l ,, '3i. \ 1. fà \ 3. %% c; u..OI 1 "1.Vtn \; j) 1.tAAlh <1:14: lt- $ sowu * iaS <tt t1M * <a @ a oM% éo% '> G; 3.a * J liimit smt? 4 ça \ i \ 1 \ 1 Jot} \\ t.1 3Htïf: n. \ .. 11 .. 1al1tWt <t:: kAt. Pn% & na \ lA " i 1.oou.



  Jffi! I1J.a.11: .ft. ?? t: 1) \ 1I1;. "\ J .. 1: I, Q-P.l! 1 \ 1, valve% 4e tldoom ..



  : tl 1t X9Zi $ .; nt t>% xgviisç 1 <11 \ l14Q de pom- hnnz $ 3 ùhcihoe **? 0) eh 1àS, 1à..tM \ .. la% a1.vOê, lJ; t de Jjtq < 3 & 8) & <ë3ist3% 1 t liS 4 <# Q * n40n% vem 408 weights 205 and 206 determined by the length of the stroke of the piston 175, When the piston 175 moves in the
 EMI30.2
 szaz cd..1Q> J! .at ..fi ,, 7L làqoàùio daas 1 n & \ 'oM 195 can At to1ft- ($ M <9ï5 $$ 1 Wt'1 \\ N à la sa1on l.uoapnd1'1 ( tuo par Q :): 1b (tit, àa cBmkb * 205 st rfa7, a daas 1 & ohoorl 195 gap la $$: 1! tsl% T3 !. 11 \\ 1d. 4in la chaabM 19 'Olt zwgrésenàùéi cszEoaaa% OE & s Clvs 4w vapor S07 tbrman doé ca @ ités in this liquid.

   The liquid contained in the chamber 190 is represented by its bubbles t. lE) level of the liquida 206 mont. hence towards the top of the room 190
During the process of cavitation of the liquid in chambers 190 and 195, this liquid possibly being oil or ethylene glycol, for example, the liquid is in theory instantly cooled by the exchange of heat. latent vaporization at a low pressure prevailing in chambers 190 and 195.

   This feature constitutes an advantage of the invention because, in known pumps, it was necessary to drift? The driving fluid when the gun is closed, which implies a maximum driving force expenditure when the gun - Let 153 is closed or not operating, whereas a high power level is not desirable for the reasons stated at the beginning of this dissertation.



   In theory, as the energy required to vaporize

 <Desc / Clms Page number 31>

 and condensing liquid in chambers 190 and 195 is relatively small, and further since the gain of latent heat of vaporization and heat of condensation exists in a heat transfer system with decreasing inactivity, i.e. say that there is a loss of heat from the steam during its condensation under pressure in the walls of the pump 152 and associated metal parts, the pump and pumping liquid are not heated, i.e. that they are cooled during periods when the valve 158 of the gun 153 is closed.

   However, the amount of liquid that must be maintained in reservoir 200 to operate the pump during periods when the gun valve 158 is closed is very small and can be on the order of one quarter (0.946 l). or less for small pumps operating paint guns and the like.



   When a stroke of the piston 175 is completed (during uninterrupted reciprocating motion of the piston during stationary periods) in a position offset 90 clockwise from the position shown for the crank 195, the travel of the piston 175 is inverted and the driving liquid contained in the chamber 195 is then compressed and condensed and the level of the liquid 205 in this chamber rises. During the reciprocating movement of the piston 175 in periods when the gun valve 158 is closed, the liquid drops 203 replenish the volume of the driving liquid at a predetermined rate in both chambers 190 and 195, during this time. .

   As mentioned above, it is preferable that this speed be fast enough so that when the valve 158 of the gun 153 is opened, the excess fluid in the accumulator 170 can meet the needs and capabilities of the gun 153 for as long as possible. reconstitution of the volume of liquid in chambers 190 and 195 to a maximum capacity desired for the

 <Desc / Clms Page number 32>

 pump 152 and diaphragm pumps 10a and 10b.

   Obviously, when the valve 158 of the gun 153 is closed again, the valves 66a and 66b actuated by the diaphragms are again closed and the driving liquid contained in the chambers.
190 and 195 is again expelled by decompression valves
192 and 192a in supply tank 200 during successive reciprocating strokes of piston 175.



   Although the drawings do not show, for operation under extremely high pressure, preset mechanical accumulators may communicate with the chambers.
190 and 195 and can be set to higher pressures than pressure relief valves 192 and 192a so as to prevent excessive shock to building parts. This technique is apparent and therefore not shown. But it is desirable that the decompression valves
192 and 192a have sufficient capacity to expel fluid during simple reciprocating strokes of piston 175.



  In Fig. 8 which shows a mechanical connection for changing the pressure and volumetric capacity of the pump, a single acting pump 210 is shown and includes a piston 211 working in a cylinder 212. A pressure relief valve 192 is shown schematically and this decompression valve may advantageously be of the preset type described with reference to Fig. 6 and is attached to an outlet 214 to a supply tank, not shown. The piston 211 is driven by a piston rod 215 moved by a lever
216. The upper end of the lever is hinged at 217 and a link 218 pivots on a bracket 219 which may be conveniently attached to the pump 210.

   The lower portion of lever 216 has a series of spaced holes 220 for receiving suitable pivots for securing an inter- link rod.

 <Desc / Clms Page number 33>

 medial 222 in turn secured by pivots in holes 223 formed in a swing arm 224 pivoting in turn at its lower end 225 on a bracket 226 suitably secured in place. The oscillating arm 224 moves to the right and to the left under the action of a connecting rod 230 shown as being driven by a crank 231 driven in rotation by an electric motor 232 supplied by the current source 233.



  The swing arm can also be moved by a hydraulic motor such as that shown in FIG. l, if desired.



   Pump 210 is shown to be operating at its maximum capacity since link 222 is connected to upper hole 223 in swing arm 224 as well as upper hole 220 of lever 216. However, pressure relief valve 192 is set for. operate at its desired minimum pressure because the stroke of piston 211, when moving, is maximum at this time. When a lower volume and higher drive pressure is desired, the link 222 can be moved to lower holes 220 and 223 to decrease the stroke of the piston 211.

   In the latter case it is preferable, when higher pressures are to be used, with a substantially constant supply of motive force to the motor 232, that the pressure relief valves 192 are replaced by pressure relief valves set for higher pressures. .



   VARIATION OF FIGURES 9 TO 14.



   A preferred embodiment of the invention will now be described with reference to Figs. 9 to 14. This embodiment of the invention is portable, which constitutes an interesting peculiarity when it comes to spraying paints and similar products. Certain parts described below can advantageously be made of aluminum in order to maintain the

 <Desc / Clms Page number 34>

 resistance while reducing weight.

   With such a construction, it has been found that a pump having a capacity of about 40 gallons (151 liters) of paint per hour at about 2000 pounds per square inch (140 kg / cm2) weighs substantially less than 100 pounds (45 kg) and is easily portable by the average painter over short distances and can be fitted with a chassis or cart on wheels to transport it over longer distances.



   The pump frame comprises two spaced U-shaped beams 240 the flanges of which advantageously extend inwardly in the position shown in FIG. 10.



  The joists 240 are connected to each other by a transverse plate 242 which is suitably secured by machine screws 244 screwed into the edges of the plate 242. The ends of the joists 240 are connected by cross members 246. upper flanges of the joists 240 also by machine screws. Screw connections are preferable, although not essential to facilitate easy assembly and disassembly of the apparatus in order to replace parts or to carry out repairs. The lower flanges of joists 240 are connected to cross beams having cantilevered extensions 248 and downwardly curved legs 250 which carry suitable vibration absorbing pads, not shown.



   A commercially available 3/4 horsepower or 1 horsepower electric motor 254 is shown attached by machine screws 255 to the upper flanges of joists 240. The motor is a 120 volt motor preferably chosen for its s' purpose. The motor 254 drives a pulley 256 which through a suitable belt 257 or similar transmission member drives a reducing pulley 258 which in turn drives

 <Desc / Clms Page number 35>

 a crankshaft 262 (Fig. 10) which has counterweights 264 serving to keep vibrations to a tolerable minimum.

   The crankshaft 260 journals at spaced points in bearings mounted on the beams 2.40, these bearings which are of a conventional type not being shown.



   Crankshaft crank pin 262 carries a conventional bearing with a housing 266 which is threaded as shown to receive a threaded end of a connecting rod 268. As crank pin 262 rotates, connecting rod 268 is driven in a 3600 cycle to. to the right and to the left as shown in Figs. 10 and 12. The connecting rod 268 is attached to a piston, described in more detail below, for driving a diaphragm pump indicated at 270. The diaphragm pump. 270 is secured to cross plate 242 by several suitable elongated machine screws 271 which also serve to secure parts of pump 270 in place in the frame.



   The actuation of pump 270 is therefore capable of introducing paint or the like into pump 270 from a suitable line 274 shown to the right in Figs. 9, 10 and 12. The paint exits through a high pressure line 276 connected to a paint gun or the like using high pressure fluid.



   Fig. 12 shows a preferred construction of the pump 270 just described. Connecting rod 268 drives piston 280. The end of connecting rod 268 has a spherical head 282 or may contain a suitably shaped recessed hard ball. The spherical end 282 bears on several radially spaced apart rolling balls 284.



  The balls 284 in turn roll on a steel washer 286 contained by a relatively soft metal washer 288 to distribute the force over the shoulder 290 of the piston 280 which is preferably made of aluminum. The spherical end 282 is secured in place by means of an O-ring 292 which is secured,

 <Desc / Clms Page number 36>

 by a steel washer 294A and held in place by a resilient snap ring 294 in a groove 296 at the left end of the recess made in the piston 280.



   The piston 280 slides in a reciprocating motion within a cylinder 298 which has a bore 300.



   As the piston 280 moves, its face 310 moves away from the full tie-down position shown to a right-hand position 310 'for compressing and discharging liquid not shown and returns to the solid line position during a' suction stroke. It is preferred that the bore 300 has a smooth finish so as to minimize the wear of the high pressure seals 304 and 306 which will be described.



   Seals 304 are gaskets which in section are U-shaped with the open side of the U facing the high pressure liquid in a pumping chamber 302. O-ring 306 serves to secure the seal. sealing and physically centering the right end face 310 of piston 280. The pressure drop across O-ring 306 is approximately half the pressure drop from the high pressure in the chamber. pump 302 during the drive stroke, and the pressure drop at the right U-joint 304 is approximately equal to the other half.

   Liquid at high pressure, that is, at a pressure below the maximum pressure prevailing in chamber 302, remains trapped between U-seals 304 and O-ring 306 and provides uninterrupted lubrication. It has been found that this construction loses a negligible amount of oil during an extended period of operation. For extremely high pressures more gaskets 304 and o-rings 306 can be used and for operation at lower pressures it is possible to decrease the number of U-gaskets and O-rings.

 <Desc / Clms Page number 37>

 shown in FIG. 12.



   The cylinder 298 is fixed by screwing at 312 in an end plate 314 for the pumping chamber 302 of the pump 270. In this embodiment of the invention, the thread 312 does not have to be leaktight. liquid since an o-ring 306 is provided cooperates with adjoining surfaces near a shoulder 318 of parts 314 and 242 and with a shoulder 320 provided on part 242 so that o-ring 316 seals against leakage pressure radially between parts 242 and 314 and axially between part 242 and the outer surface of cylinder 301.



   This liquid pumping chamber 302 is laterally confined in a thick-walled ring 325. The ring 325 is secured to one half 326 of the pump 270 by long screws 271 which pass through suitable holes in the plate. cross 242, end plate 343, ring 325 containing the pumping chamber and which thread into half 326 of the pump.



   A substantially identical pump half 326 'is attached by bolts' 327 to pump half 326 to secure, between slightly offset shoulders, substantially planar faces adjacent to shoulders 328 in order to clamp a diaphragm 330 between. them. The diaphragm 330 carries at its center a valve 335 fixed by a bolt 332 or the like, this valve being identical to the valve described above in conjunction with the previous embodiments of the invention.



  The valve 335 is intended to cooperate with flats 336 and 336 'which determine the limits of the stroke of the valve 335 and of the diaphragm 330 in the same way as that described in more detail above.



   A chamber for the pumped fluid 340 is delimited by a thick-walled ring 342 secured by an end closure plate 344 by suitable machine screws 345 which interlock.

 <Desc / Clms Page number 38>

 screw into the 326 'half of the pump. The pumping chamber 340 communicates with an outlet fitting 346 which in turn is connected to parts of an outlet valve described below, this outlet valve in turn being connected to the high pressure hose 276. , Figs. 9 and 10.



   An inlet valve 350 is placed inside the pumping chamber 340 in this variation of the invention. The inlet valve 350 is in the form of a ball check valve 352; the ball may be nylon or other suitable material and is preferably lightweight so as to have low inertia as it moves away from and returns to its seat 358. The ball 352 of the inlet valve is contained in a cage 354 having guide arms 355 which are preferably three in number and equally spaced around the ball and capable of guiding it as it approaches and s The cage 354 containing the ball 352 is biased by a spring 356 which reacts between the outwardly curved ends of the cage 354 and the right central surface of the pump half 326.

   The seat of the valve is in the form of a plate 358 pierced with a round central hole and fixed between a shoulder flange in the ring 342. O-rings 328 identical to those described above are placed in suitable annular grooves. to make the pumping chamber 340 sealed against axial fluid leaks.



   When the diaphragm 33 and the associated valve :: 335 move to the left due to a sliding of the piston 280 to the left, fluid under a low pressure is introduced into the tube 274 through the fitting 380 to urge the ball. 352 to the left allowing pumped fluid to enter the pump side of diaphragm 330 into pump 270. As piston 280 moves to the right, pumped fluid is discharged through fitting 346 and ball 352 is pressed. seated at this time against its seat 358 under the combined action of

 <Desc / Clms Page number 39>

 fluid under pressure and the bias of the spring 356.



   Fig. 14 shows the fluid outlet valve 360 for the pumped fluid which is connected to fitting 346 (Fig. 12) by fitting 362 forming a suitable valve seat. Fluid under pressure enters the fitting 362 forming the seat of the valve and this fitting is provided with a conical valve seat 364 at its upper end, in the position shown.



  A suitable ball 366, which may be nylon or the like, is biased by a spring 368 downward in the position shown in FIG. 14. The spring 368 reacts against a seat 370 formed in a connector 372. It appears from the drawings that the connector 360 has the fore of a tee and that the threads cooperating with the connectors 362 and 372 are of the same pitch and extend the full length of the fitting so that this fitting can be fabricated in a single pass in a fitting drilling machine and threading 374 threads. The tee fitting includes a side tubing 376 which is drilled and tapped. Threaded to receive a fitting 377 which in turn is connected to a purge valve 372.

   The purge valve is commercially available and is opened when the pump is turned on to expel air from pump 270 until pumped fluid appears at the outlet of a tube not shown connected to the valve. purge 372.



   The fluid inlet fitting 380 is shown in section on a larger scale in FIG. 13. The fitting 380 includes an elbow 382 having male threads 334 intended to form a fluid-tight seal with female threads 386, FIG. 12. The other end of the elbow 380 is intended to receive a cap nut 386 in order to compress a conical nozzle 388 so as to press the far end of the tube 374 against an interior nozzle 390 in order to obtain a fluid tight seal. at the entrance to the elbow 380.



   The pumping liquid circuit will now be described.

 <Desc / Clms Page number 40>

 



  The liquid is stored in a reservoir 392 which is suitably mounted to deliver liquid by gravity as shown in FIG. 9 above the joists 240 and which is arranged across them. Reservoir 392 in this embodiment is preferably of relatively small capacity because it is simply required to receive a small amount of bypass fluid. Reservoir 392 may include a suitable internal filter, not shown, to separate foreign matter from the pumping liquid. The pumping liquid can be connected by conventional shut-off valves 393 and 393 'to the supply and purge sides of the pumping liquid circuit in pump 270.

   The pumping liquid is delivered by several tubes and fittings indicated generally by the numbers 395 on the low pressure side and 396 on the high pressure or purged side of the circuit. A calibrated orifice 394 or a valve of the type needle can be used and is commercially available.



  If the needle valve is used, this valve can be fitted with a quick adjustment handle 394 'which can be removed after proper adjustment to deliver a measured quantity of pumping liquid through an inlet check valve 4001 into the pump. pumping circuit to prevent misfiring.



   As clearly shown in Fig. 12, the inlet fitting 395 'is mounted near the bottom of the ring 325 containing the pump chamber to introduce oil into the bottom of the pump side of pump 270. As also shown. In Fig. 12, the outlet fitting 396 'is placed at the top so that all air in the pumping liquid side of the circuit is first purged before the oil is purged from the circuit. When the pumping system is turned on, the pumping liquid side of pump 270 is automatically purged by gravity of the air it contains.



   When the paint gun outlet valve 158, connected to the pumped fluid outlet tube 276, is closed,

 <Desc / Clms Page number 41>

 paint is still sucked into the pumped fluid chamber, and as the pressure in the pumped fluid chamber rises above the pressure in the pumped fluid chamber, valve 335 and diaphragm 330 move toward a position opposite to that shown in FIG. 12. When valve 335 contacts seat 336, pumping chamber 302 has a fixed minimum volumetric capacity and the amount of pumping liquid in excess of the minimum volumetric capacity of chamber 302 is purged. from fitting 396 'via check valve 400r to reservoir 392.



   When the pumping chamber 302 and the liquid communication passage in the pump are purged of this excess pumping liquid, cavitation occurs in the pump and ensures that the pumping liquid is vaporized and condensed to a high degree. cyclically by the pressure variations in the pumping chamber caused by the reciprocating displacement of the piston 280 to decrease the driving force requirements of the electric motor 254 and to cool by cavitation the liquid contained in the pump and the parts of the pump as explained in more detail above.



   The construction of a preferred check valve, for both valves 400i and 400r, is generally indicated at 400 in FIG. 11. The check valve 400 comprises a substantially tubular body 402 provided with uniform threads 404 along its entire interior length. The threads are intended to receive 'at one end a fitting 406 and at the other end a fitting 406' threaded so as to be screwed into the body 402. The fitting 406 'can be connected to an inlet or outlet pipe. in the direction in which check valve 400 acts to contain the flow of fluid.

   The fitting 406 is counterbored to receive a valve sleeve 410 comprising an inner flange 412 forming a valve seat 414. The seat 414 is intended to cooperate with a ball 415 which may be of steel or of another. appropriate material. Ball 415 is attacked by a plate

 <Desc / Clms Page number 42>

 416 biased by a spring 418, this spring bearing against an adjustment nozzle 420 pierced with a central orifice and being adjusted by the latter. The central orifice of the nozzle 420 may be provided with an irregular lumen 422 for the passage of liquid intended to receive a suitable tool for adjusting the compression of the spring 418.



   When the check valve 400 is to be used as the inlet valve 400i for pumping liquid, the tension of the spring 418 is kept very low so that the atmospheric pressure acting on the ball 415 can overcome the pressure. force of spring 418 to admit a flow of liquid measured in the direction of the arrow to the left of Fig.ll.



  As briefly mentioned above, it is desirable in this preferred variation of the invention which applies to a portable spray painting apparatus that about 20 cycles of the piston 280 are required to provide sufficient pumping liquid to allow for the diaphragm pump to operate to pump fluid with maximum stroke. Of course, with different orifices in the paint guns, different amounts of fluid can be sprayed with different guns; With this being the case, oscillating purging and filling of pumping liquid occurs when the valve mechanism 335 contacts either seat 336 and 336 'during its reciprocating motion. comes into the diaphragm chamber of pump 270.

   In operation, the purge and feed functions are more or less irregular depending on the operation of the guns. Prolonged periods of gun operation, without intermittent shutdown, result in a different purge and refill frequency than that which occurs with frequent short spray gun applications, with relatively dwell or shutdown times. prolonged between applications and, during

 <Desc / Clms Page number 43>

 during downtime, the drive liquid in the pump is subjected to a cavitation effect.



     COOLING BY CAVITATION.



   When pumping paint, for example at 2000 psi (140 kg / cm2) and then closing the gun, during a compression stroke of piston 280, a shock load occurs which may occur. approach 4000 pounds / square inch (280 kg / cm2). By using a properly adjusted 400r pressure relief valve, the pumped and pumped fluids can be maintained at a maximum pressure of between 2000 and 3000 pounds / square inch (140 and 210 kg / cm2), about 2500 pounds / square inch or 175 kg / cm2 for example,

   when the rear central valve provided on the diaphragm 330 comes to be placed against the seat 306 to maintain the pumping liquid at an exact minimum quantity when the pumping piston 280 is at its compression top dead center 310 '. The oil is slightly compressed according to the pressure transmitted to it by the pumping piston 280.



   During the suction or return stroke of piston 280, in theory, although it is not certain, it is believed that the pressure of the pumping liquid, usually oil, in the pumping chamber 302 drops instantly. at a pressure close to absolute zero. It appears that the sudden expansion of the oil during the return or suction stroke of the piston causes an instantaneous vaporization of a fraction of the oil in the pumping chamber, the heat of the oil being given up in favor. steam and the temperature of the oil being lowered.



  A very small amount of cold feed oil passes through the 400i control valve and mixes with the pumping oil in the pumping chamber to also maintain the temperature of the pumping fluid and associated parts of the pump. a favorable value for operation.



   During the next compression stroke of piston 280,

 <Desc / Clms Page number 44>

 the vapor condenses and a very small amount of driving oil in the pumping chamber is purged by the pressure relief valve 400r. As it condenses, the vapor draws a certain amount of heat back to the oil. But, apparently because the steam has formed quickly and the condensation takes place less quickly, the steam is compressed and is brought to a temperature higher than that of the oil and the parts of the pump and the heat. steam is transferred by the pump parts and is discharged from the oil. A useful cooling is therefore obtained for the parts of the pump in contact with the oil.



   It should be noted that recirculation of a large quantity of the oil is not considered essential for the cavitation cooling of the pumping liquid. However, a weak circulation of oil is provided in the pump described, in order to supply supply oil to the mass of pumping oil when the gun is open. The amount of reconstituting oil is measured so as to increase the volume of the driving liquid in the pumping chamber in about 20 to 100 piston cycles, for example depending on the desired operating characteristics.

   With an increased number of strokes to replenish the mass of liquid, the efficiency of the cavitation cooling function is increased. However, a prolonged replenishment time is required to replenish the pumping liquid in the pump 220 in order to obtain maximum pumping capacity.



   Pump 270, in the example described above, operates at about 600 piston cycles per minute. To replenish the drive fluid to maximum pumping capacity after a period of cavitation operation, approximately 20 cycles should be allowed, which requires approximately 2 seconds. But the pump starts pumping fluids in a much shorter time interval at a lower capacity

 <Desc / Clms Page number 45>

 at its maximum pumping capacity. The pump also measures the oil flow during the cavity because at this time a minimum pressure is present in the pumping liquid chamber.



   Of course, the invention is not limited to the forms and details of execution described and shown, to which changes and modifications can be made without departing from its scope.


    

Claims (1)

R E V E N D I C A T I O N S. :. 1. Fluid transfer apparatus of the type comprising a body forming a first and a second chamber separated by a movable separation mechanism between these chambers, characterized in that it comprises a regulating device for an outlet of fluid from the first chamber, a device for supplying the second chamber with pumping liquid comprising a vapor phase, a device responsive to a predetermined pressure variation in at least one of the chambers to establish a predetermined volumetric capacity in the second chamber and a mechanism for exerting pressure. pressure forces on the liquid in the second chamber, this mechanism being operable to act on the liquid contained in the second chamber in order to move the movable mechanism for passing the fluid through the first chamber except when the pressure sensitive device has established the predetermined volumetric capacity in the second chamber and to acting on the liquid to cycle at least a portion of the liquid between its vapor and liquid phases when the pressure sensitive device has established the predetermined volumetric capacity in the second chamber. 2. Fluid transfer apparatus of the type according to claim 1, placed between a driving device and a variable load such as a paint gun, characterized in that it comprises a relatively incompressible pumping liquid inter- <Desc / Clms Page number 46> wedged between the driving device and the transfer apparatus and a mechanism responsive to load variations driven by the transfer apparatus to set a condition establishing drive and non-drive relationships between the driving device and the transfer apparatus. A transfer apparatus, the non-driving relationship being characterized by cyclic vaporization and condensation of the liquid so as to limit the consumption of motive force of the motive device. 3. Fluid transfer apparatus of the type specified according to claim 1 or 2 forming a portable pump for a product such as paint, the pump comprising a motor device driven by a liquid which acts on the product contained in a chamber. , a motive force limiting device for the motive device, characterized in that a first control device serves to drain pumping liquid from the chamber in response to a first predetermined state, and a second device. positive control is used to introduce pumping liquid into the chamber in response to a second predetermined state. 4. Fluid transfer apparatus of the type specified according to claim 1, 2 or 3, characterized in that it comprises a control valve comprising a body comprising screw threads of uniform pitch and diameter, these threads s 'extending into the body over its entire length so that the body can be fabricated by means of taps working on one side of the body only, a valve seat capable of co-operating with the threads to be secured in one side of the body, and a movable valve comprising a support and capable of cooperating with the screw threads to be fixed in another side of the body. 5. Fluid transfer apparatus of the type specified in claim 1, 2 or 3, characterized in that it comprises a replaceable valve for abrasive materials and the like moved under high pressures, said valve comprising a valve. perforated hard metal disc forming a seat <Desc / Clms Page number 47> and a nylon valve, the seat and valve being so arranged and proportioned that material pressures of 1000 pounds per square inch (70 kg / cm2) and greater are incapable of extruding the nylon through a perforation in the nylon. headquarters. 6. Fluid transfer apparatus of the type specified according to claim 1, 2 or 3, characterized in that it comprises an angularly variable mechanical driving force transmission device mounted between a driving device and a device using the driving force comprising a head in spherical part driven by the driving device, several rolling balls intended to transmit the thrust of the head to the device using the driving force, a hard support member in contact with the rolling balls and opposite the head and at least one member of elastic stop opposite to the support member and in contact with the head to keep the head in contact with the balls. 7. Apparatus, in substance according to claim 1, characterized in that the movable mechanism separating the chambers comprises a flexible diaphragm. 8. Apparatus according to claim 7, characterized in that the diaphragm comprises a force transmitting device for driving the force applicator mechanism. 9. Apparatus, in substance according to claim 8, characterized in that the force transmitting device comprises a valve. 10. Apparatus according to claim 1, characterized in that the mechanism capable of being actuated comprises a pressure relief valve. 11. Apparatus according to claim 10, characterized in that the decompression valve is sensitive to the pressure of the liquid. 12. Apparatus according to claim 11, characterized <Desc / Clms Page number 48> in that the pressure relief valve is disposed relative to the liquid so as to purge the liquid from the second chamber to establish the predetermined volumetric capacity. 13. Apparatus according to claim 1, characterized in that it comprises a pressure controlled inlet device for controlling the flow of liquid into the inlet of the second chamber. 14. Apparatus according to claim 13, characterized in that the inlet device comprises a calibrated orifice having a volumetric flow rate sensitive to a difference in liquid pressure passing through the orifice. 15. A pumping apparatus according to claim 1, 2 or 3, characterized in that it comprises a driving liquid and a device for adjusting the volume of liquid for causing cavitation of the liquid in at least one predefined pumping state. - finished. 16. A pumping apparatus according to claim 1, 2, 3 or 15 ,, characterized in that it comprises a device for driving a liquid comprising vapor and liquid phases reversible to pump the fluid and a device for command to reverse the phases. 17. Apparatus according to claim 16, characterized in that the control device effecting the reversal comprises a pressure-controlled pumping liquid decompression device. 18. Apparatus according to claim 16, characterized in that the control device effecting the inversion comprises a volumetric device for driving the liquid. 19. Apparatus according to claim 17, characterized in that the control device effecting the inversion comprises a measuring device for supplying the driving or pumping liquid. <Desc / Clms Page number 49> 20. Pump driven by a liquid, characterized in that it comprises a body containing a diaphragm driven by a liquid forming a movable partition for a variable volume chamber serving to drive a fluid comprising a lumen formed in the body comprising a chamber. extended interior valve seat, of a first predetermined area, and a valve having a perimeter edge surrounding a less extensive predetermined area, the edge being able to cooperate with the seat to close the lumen, the diaphragm being attached to the valve on the side thereof this opposite to the light and extending beyond the edge, the diaphragm being able to come into contact with the surface of the seat situated beyond the edge and the edge of the valve being in contact with the seat. 21. Pump according to claim 20, characterized in that the extended valve seat is substantially flat and the valve is planar to come into intimate contact with the seat. 22. Pump according to claims 20 and 21, characterized in that the edge is chamfered in a direction away from the diaphragm to reduce the stresses exerted in the diaphragm affected by the variations in the liquid pressure at which it is. submitted. 23. Pump according to claims 20,21 and 22, characterized in that it comprises a second lumen provided in the body on the opposite side of the diaphragm, substantially identical to the first lumen and comprising a second seat surface also extended, and a second valve of size and shape identical to the first and capable of cooperating with the second seat to close the second lumen, the diaphragm being fixed between the first and second valves. 24. Pump according to claims 20 to 24, characterized in that it comprises a mass of pumping liquid driven mechanically and a device for driving the mass of liquid to move the diaphragm and the valve in a back and forth movement. <Desc / Clms Page number 50> comes which brings the valve closer and apart from its seat. 25. Pump according to claim 24, characterized in that it comprises a control device serving to maintain a predetermined quantity of liquid in the mass. 26. Pump according to claims 20 to 25, characterized in that it comprises a mechanical drive device for the mass of liquid for moving the diaphragm and the valve in a reciprocating motion which brings together and push the valve away from its seat. 27. Pump according to claim 26, characterized in that it comprises a control device serving to maintain a predetermined quantity of liquid in the mass of liquid in a predetermined operating state of the pump. 28. Pump according to claim 22, characterized in that the peripheral part of the edges of the valve is chamfered so as to form a cutting edge. 29. Apparatus for controlling the amount of liquid contained in the pump from a source of pumping liquid, characterized in that it comprises a liquid supply valve in liquid communication between the source and the side of the pump. driving the diaphragm, the supply valve being biased to a closed position and being opened by relatively low liquid pressure, and a liquid pressure relief valve in liquid communication with the inlet side. dragging of the diaphragm, this decompression valve being pressed to its closed and open position by the pressure exerted by the pumping liquid which exceeds the pressure of the pumped fluid, the first valve, when it is in contact with its seat actuating the decompression valve in a limit position at the diaphragm. 30. A liquid actuated diaphragm fluid pump according to any one of the preceding claims, characterized <Desc / Clms Page number 51> in that it comprises a diaphragm having two limit positions and a reciprocating piston for discharging the liquid to drive the diaphragm, the first controller controlling the quantity of pumping liquid forming the mass of liquid in a limit position of the diaphragm. 31. Apparatus according to claim 30, characterized in that the second control device adjusts the amount of liquid present on the pumping liquid side of the diaphragm to modify the operation of the first control device. 32. Apparatus according to claims 30 and 31, characterized in that at least one device controlling the amount of liquid is mounted on the piston. 33. Apparatus according to claim 32, characterized in that the liquid control device comprises a flexible lamella valve mounted on the face da piston in contact with the mass of liquid. 34. An apparatus according to claim 33, characterized in that a plurality of liquid control devices are used to increase the capacity of liquid flow from the source to the body of liquid. 35. Pump according to claim 30, characterized in that the liquid decompression valve is a calibrated valve comprising a body forming a valve seat of predetermined section, a movable valve intended to come into contact with the seat and urged by. the pressure of the mass of liquid in the region of the seat, a preset spring biasing the movable valve into contact with the seat and assuming the pressure of the liquid, and a device for mounting the calibrated valve in a liquid-tight manner, this valve being actuated by liquid pressure. 36. Apparatus of the type specified for supplying fluid such as paint to an intermittently operated, low capacity paint gun or the like, <Desc / Clms Page number 52> characterized in that it comprises a constant displacement or positive displacement pump, a variable displacement pump capable of being actuated by the positive displacement pump, a hydraulic drive device between the pumps, and control devices. control used to make the hydraulic system less efficient when the paint gun is in its low capacity state. 37. Apparatus according to claim 36, characterized in that the gun operates by all or nothing, that is to say that it can be opened or closed and the control devices prevent the hydraulic device from operating when the paint gun is closed. . 38. Apparatus according to claim 37, characterized in that the liquid has vapor and liquid phases. 39. Apparatus according to claim 33, characterized in that the control devices comprise liquid supply and pressure relief or leakage devices in communication with the drive device. 40. Apparatus according to any one of claims 37, 38 or 39, characterized in that the positive displacement pump is a piston pump. 41. Apparatus according to claim 40, characterized in that the variable displacement pump is a diaphragm pump. 42. Apparatus according to any one of claims 36 to 41, characterized in that the gun is actuated between an open state and a closed state and the control device causes cavitation and condensation of the liquid. 43. Apparatus according to claim 42, characterized in that it comprises an accumulator serving to affect the operation of the control devices. 44. Apparatus according to claim 2, characterized in that the motor device is a pump and the variable load <Desc / Clms Page number 53> is a paint gun. 45. Apparatus according to claim 44, characterized in that the pump is a positive displacement pump and the variable load is a paint gun capable of comprising calibrated orifices of different dimensions. 46. Apparatus according to claim 45, characterized in that the smaller orifices cause cyclic vaporization and condensation of the liquid at more frequent intervals than larger orifices. 47. Apparatus according to claim 45 or 46, characterized in that complete sealing of an orifice causes uninterrupted cyclic vaporization and condensation of the liquid. 48. A variable capacity fluid transfer system actuated by a driving device, according to any one of the preceding claims, coupled to a load of variable capacity and comprising a source of motive force for driving the load, characterized by a transmission of motive force between the drive device and the load and an automatic control device responsive to the load demand to cause the transmission fluid to act in a manner controlling the temperature of the transmission device of liquid motive force. 49. Valve according to claim 6, characterized in that it comprises a body comprising a first part and at least one other part, at least one of the parts of the body supporting the valve and at least two parts of the body supporting the seat. 50. Fluid transfer apparatus for a material of the type described, characterized in that it comprises a driving device driven by a liquid in a chamber, a driving force limiting device for the driving device comprising <Desc / Clms Page number 54> control devices for decompressing the liquid chamber in response to a first predetermined state, said control devices being oriented to exhaust air from the chamber before the liquid. 51. A method of pressurizing a fluid in; this type transfer apparatus specifies, characterized in that a driving or pumping liquid having a liquid-vapor phase readily, is provided in the apparatus and that The pressure of the liquid is cyclically modified to vary the pressure of the fluid by pressurizing the liquid in a first state of pressure and by performing inversions between the liquid and vapor phase of the liquid in the pumping liquid while the liquid exerts a pressure on the fluid in a second state of pressure. 52. The method of claim 51, characterized in that the pumping liquid is moved cyclically in a reciprocating motion to effect inversions between the vapor and liquid phases in the mass of liquid while animating, this mass of a back and forth movement. 53. A method for pumping fluid according to claim 51 or 52, characterized in that the phases are reversed by reducing the volume of the mass of liquid. 54. Process for pump? fluid according to any one of claims 51, 52 and 5, characterized in that the inversion phase consists in positively displacing part of the pumping liquid. 55. Process for pump? fluid according to claims 51 to 54, characterized in that the reversal comprises the supply of a measured supply of pumping liquid to the mass of pumping liquid. 56. A method for pumping fluid according to claims 52 to 55, characterized in that the reversal comprises the dim- <Desc / Clms Page number 55> EMI55.1 decrease in volume of vapor while the mass of liquid is less than causing cavitation. of ma- ,. By increasing the volume of the mass of liquid, moving this mass in a different direction while suppressing the vapor. EMI55.2 ? d + # Process <.oQT ": i .Ji fluid according to one 57. Process pDures5urisQr of the fluid according to any one of claims 51 to 56 characterized in that the displacement seen ± ÉÀique'd'une pump is regulated to obtain volume displacement regulation; of a pump to obtain different operating pressures of the pumped and pumping fluids, with a motive pumping substance, with a consumption of motive force substantially uniform. A method of controlling the temperature of a liquid in a the @ mo corrugating wall chamber of variable volume while the liquid is cycling between a first state of filling of a predetermined volume and a second state of filling of a predetermined volume. EMI55.3 vol.ume partz cbambre, characterized pre-determined partial volume,. anx "the chamber, characterized in that liquid is supplied so that there is at least sufficient liquid to obtain the first state of volume filling, the liquid is purged in the state of volume filling at a high pressure and the volume is cyclically changed EMI55.4 of the chamber between the first and second volume state to cause vaporization of the liquid and subsequent condensation EMI55.5 vapor in contact with the liquid and the walls of the chamber in order to regulate the temperature of the liquid and of the chamber. bre in order to adjust ": I '" "% $ <i", y, th room. 59. Proc4µé. + ".Q, r aàication 58 ,, characterized in that intro" .ide measured in the chamber to prevent j / µi chamber from being less than the first state of filling V04e 60. proCéé '. . redicatlon 58 or 59, characterized in that 1ntrQ.Q .; >. /, ": is shown whenever the volume of the liquid is changed from the first volume state to the second partial ume filling state. <Desc / Clms Page number 56> 61. A method according to any one of claims 58, 59 and 60, characterized in that the pressure of the liquid is maintained between predetermined upper and lower pressure limits as the volume of the chamber varies between the first and the second volume state. 62. A method according to any one of claims 51 to 61, characterized in that the high pressure of the liquid is sufficient to compress by about 1% by volume at least one petroleum product. 63. The method of claim 62, characterized in that the petroleum product is lubricating oil. 64. A method according to claim 63, characterized in that the oil is largely # 5 lubricating oil and a small portion is kerosene. 65. The method of claim 64, characterized in that the oil contains about 4 parts of oil and about 1 part of kerosene. 66. A method according to any one of claims, 51 to 65, characterized in that the number of cycles per minute is modified in order to control the rate of variation between the vapor and liquid phases. 67. Fluid transfer apparatus, substantially as described with reference to the accompanying drawings. 68. A method of pressurizing liquid, substantially as described with reference to the accompanying drawings.