MX2014012861A - Direct volume-controlling device (dvcd) for reciprocating positive-displacement pumps. - Google Patents

Abstract

A volume control device having a housing with an inlet passage, an outlet passage, and an internal chamber communicating with the inlet and outlet passages. An accumulator is movably positioned within the internal chamber and substantially conforms with walls of the internal chamber, the accumulator including an internal passage allowing fluid flow therethrough. An one-way valve is positioned in the internal passage of the accumulator where the valve is biased in a closed position and an adjustable seat is positioned within the housing internal chamber between the accumulator and the housing outlet passage. A positioning mechanism engages the housing and adjustable seat whereby the position of the adjustable seat within the housing internal chamber may be adjustably fixed.

Description

DIRECT VOLUME CONTROL DEVICE (DVCD) FOR RECIPROCATING POSITIVE DISPLACEMENT PUMPS This application claims the benefit under 35 USC §119 (e) of United States document Serial No. 13 / 827,136, filed on March 4, 2013, which claims the benefit under 35 USC § 119 (e) of the document of United States Serial No. 61 / 639,524, filed on April 27, 2012, both of which are incorporated by reference herein in their entirety.

Field of the invention The present invention relates to pumps and fluid injection systems.

Background Positive displacement pumps are used to supply or "dose" a predictable, precise amount of fluid in a repeatable manner. Commonly, positive displacement pumps use reciprocating movement of a solid object such as a plunger, piston or diaphragm to draw fluid that a source continues during a suction stroke, to then move the extracted fluid during a discharge path. In such alternative positive displacement pumps, it is typical to control the flow of fluid so that the extracted part of fluid does not return to its source during the discharge cycle, but is it prevents it from doing this by means of a suction check valve that allows flow only in one direction, towards the pump. It is also typical that a discharge check valve is present to direct the flow out of the pump and into the intended receiver process and to prevent any fluid from returning to the pump from the receiving process during its operation.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 illustrates a positive displacement pump.

Figure 2 illustrates the position of a Direct Volume Control Device (DVCD) on the pump of Figure 1.

Figure 3 is a perspective view of an embodiment of a DVCD.

Figure 4 is an exploded view of the DVCD illustrated in Figure 1.

Figure 5 is a cross-sectional view of the DVCD illustrated in Figure 1 in a first position.

Figure 6 is a cross-sectional view of the DVCD illustrated in Figure 1 in a second position.

Figure 7 is a cross-sectional view of the DVCD illustrated in Figure 1 in a third position.

Figure 8 is a cross-sectional view of the DVCD illustrated in Figure 1 in a fourth position.

Figure 9 is a cross-sectional view of the DVCD illustrated in Figure 1 in a fifth position.

Figure 10 is a cross-sectional view of the DVCD illustrated in Figure 1 in a sixth position.

Figure 11 is a perspective view of a second embodiment of the DVCD.

Figure 12 is a cross-sectional view of the DVCD illustrated in Figure 11.

Figure 13 is a perspective view of a third embodiment of the DVCD.

Figure 14 is an exploded view of the embodiment of the DVCD shown in Figure 13.

Figure 15 is a cross-sectional view of the DVCD illustrated in Figure 13.

Figure 16 is a cross-sectional view of the DVCD illustrated in Figure 13 showing the fluid path. Figure 17 is a cross-sectional view of a fourth embodiment of the DVCD.

Figure 18 is an enlarged view of the DVCD seen in Figure 17.

Figure 19 is a view similar to Figure 18, but illustrating a different position of the plunger.

Figure 20 is an end view of the DVCD / pump unit showing the section line used in Figure 21.

Figure 21 is a sectional view of a modification of the DVCD embodiment seen in Figure 17.

Detailed description of selected achievements Figure 1 illustrates a conventional type of positive displacement pump assembly, with an "actuator" portion 100 and a pump "head" assembly 105 (also referred to as a "wet end" or a "fluid end"), among other terminologies). The head assembly 105 is the part of the pump assembly that comes into contact with the fluid to be pumped. Naturally, the pump head assembly 105 illustrated is only one of a multitude of pump head designs that are employed in positive displacement pump systems. The actuator portion 100 of the pump assembly is also only one of several designs that are employed in alternative positive displacement pumps. The actuator could be, and frequently is, energized by pressurized (pneumatic) gas, in which a piston oscillates over time driven by the alternative gas pressure (see for example the pump in United States Patent No. 8,087,345 , which is incorporated by reference in the present document). The actuator could also be electric, for example, where a rotary motor uses mechanical means to convert that rotary motion into reciprocating motion. The actuator could also be driven by a hydraulic fluid or any other source of energy, in which that energy is finally a repeatable, alternate, alternative movement. The type of actuator shown in Figure 1 is pneumatic, for illustrative purposes only, and many different types of conventional or future development actuators could be employed with the present invention.

Many embodiments of the present invention relate to controlling the flow or exit of the fluid from the pump in the head part of the pump assembly. In Figure 1, a pump head 105 of the plunger type is shown. In this conventional type of pump head, an actuator acts after a plunger in a linear reciprocating movement (forward and backward). The plunger is connected to the pump head using a seal, which is designed to create a barrier between the environment and a chamber inside the head, isolating the chamber hermetically. The seal allows the plunger to move in a sliding manner up and down the chamber while maintaining a watertight seal. When the plunger backs partially, but not completely, from the chamber inside the head, it creates a suction (negative pressure) inside the chamber. Figure 1 also shows a suction check valve 106 attached to the head portion 105. When the check valve 106 is fixed to a fluid source, the fluid is drawn into the pump chamber, filling the expanded space created by the plunger in retreat. At a certain point, the plunger (under alternative movement of the actuator) stops moving back and begins to descend back into the chamber. This action raises the pressure in the chamber, causing the suction check valve 106 to close, and forcing fluid out of the chamber through a discharge check valve 107.

Several other types of positive displacement pump heads use various means to alternatively create negative and then positive pressure to introduce and then discharge fluid in a controlled manner. In each of these pump head designs, at least one suction check valve and at least one discharge check valve are employed. For example, a second, very common type of pump head, not illustrated in the drawings, is known as a "diaphragm" type pump head. This pump head uses the pressure of a hydraulic fluid, generated by the reciprocating movement of a plunger, to act on one side of a diaphragm or diaphragm packing. In this type of head design, the fluid that is pumped is driven by the opposite side of the diaphragm or set of diaphragms. Other types of pump head use alternative means of control, actuation, and pumping of fluid, for example bellows-type pump heads. All the said pump heads, and potentially many other conventional and future pump heads development, can be used in conjunction with the present invention.

Many embodiments of the present invention relate to the control of the amount of fluid that is discharged during the discharge cycle of any alternative pump, regardless of the type, including where the pump head uses a discharge check valve and mechanically changes the internal volume of the camera through the alternative movement. Figure 2 depicts a pump assembly similar to Figure 1, but with the replacement of the discharge check valve 107 with an embodiment of the present invention, the Direct Volume Control Device (DVCD) 1.

Figure 3 best illustrates the external features of this embodiment of the DVCD 1 with it removed from the pump assembly. Figure 3 shows, in relation to the DVCD 1, the casing 2, end cap 7, inlet 3, outlet 4 and volume adjustment mechanism, which in the illustrated embodiment is the control button 35, which includes an indicator ring 36 graduate. The inlet 3 may include any conventional means for connection to a pump head, for example, a threaded fitting 70 through which the inlet 3 is formed. Similarly, the outlet 4 may have a threaded surface or other means of connection that allows the attachment to a pipe or proper conduction from the DVCD 1 to the process that requires the fluid to be measured or pumped to it. Various means for connecting the DVCD 1 to the pump head and to the process are contemplated in the present invention. For example, the threaded part at the bottom could be a threaded tapered pipe or any other conventional or future developed mechanical means. In the preferred embodiment, the attachment to the pump head is through a direct thread with a sealing means (eg, an O-ring type seal located in a sealing groove 39) for sealing against the pump head . The threaded part near the outlet 4 could be any type of thread that corresponds to the process for which it is to be used, or it could also be made to accept low pressure "stamped" pipe fittings, or "conical and threaded connections" "of medium or high pressure, for example. The internal components of the DVCD 1 can be better understood by looking at Figure 4 (an exploded view of the DVCD 1) and Figure 5 (an open section view of a DVCD 1 set). Figure 5 illustrates how the thread 38 at the upper end of the housing 2 will engage matching threads on the end cover 7 with an O-ring 8 to form a seal between these elements. Formed within the housing there is an internal chamber 5, which will include the main components of a mechanism or means of seating (in this embodiment the adjustable seat 16), a valve anti-return 45, an accumulator 10, and a positioning mechanism or means 20 to allow the position of the accumulator 10 to be adjusted as described in more detail below. The lower end of the inner chamber 5 includes tapered side walls 9 to facilitate a sealed engagement with the accumulator 10. In certain embodiments, the internal chamber 5 includes a volume which can be referred to as the accumulator chamber.

The illustrated embodiment of adjustable seat 16 is best seen in Figure 4. This embodiment includes the circular base 60 with the sealing ring groove 64 and a raised section 61 with elliptical opening 62 and cam rods 63 (e.g., a shank upper cam 63B and a lower cam rod 63A, whose function will be explained below). Figure 5 illustrates how the separator 17 slides within the circular base 60 and the square ring seal 18 is positioned within the slot 64 to form a seal with the inner side walls of the inner housing chamber 5. Figure 4 it also shows how this embodiment of the accumulator 10 includes a main body 14, an upper section 41 of smaller diameter, a sealing groove 42 and a lower open passage 44 (see in Figure 5). Looking at Figure 5, it is seen how this embodiment places the square sealing ring 11 and a sealing ring 12 in the sealing groove 42.

Figure 5 also shows how the passage 44 communicates with an internal cavity 15 that is formed in the body of the accumulator 14 and how the upper section 41 of smaller diameter slides inside the separator 17 within the circular base 60 of adjustable seat 16 The illustrated embodiments of the accumulator 10 additionally include a non-return valve 45 located inside the internal cavity 15 of the accumulator. In these embodiments, the check valve is shown as a seat-type valve, which includes the plug 46, the differential pressure spring 47, the spring retainer 48 and the O-ring 49. The plug 46 includes a series of side openings 50 and although hidden from view, an open upper section so that fluid entering the lateral openings of the shutter may exit through the open upper section. It can further be seen that the spring 47 deflects the end of the plug 46 having the O-ring 49 against the lower part of the internal cavity 15 of the accumulator. Although the illustrated embodiments show a non-return valve formed with a shutter assembly, many conventional or future developed non-return valves may be used, as non-limiting examples, various regulators (eg back pressure regulators), solenoid valves or shut-off valves.

Figure 4 better illustrates the individual components of an embodiment of the positioning mechanism 20, which affects the position of the adjustable seat 16 and finally of the accumulator 10 as explained in greater detail below. The main components of the positioning mechanism 20 include an axis 21, cam elements 22A and 22B and a button 23 that acts as a control surface or grip surface for the application of a torque to the shaft 24. Other components of the positioning mechanism 20 include coil springs 29, washers 28, support rings 27, O-rings 26, a ring graduated scale 24, fixing rods 25 and screw 30. the shaft 24 is positioned extending through the elliptical opening 62 of seat 16 (seen better in Figures 5 and 6) and the fixing rods 25 will fix the cam elements 22 against rotation on the axle 21 with the cam surfaces 33 (Figure 5) of each cam element oriented approximately opposite each other. yes. Looking at Figure 5, it can be understood how the rotation of the cam elements 22 causes the cam surfaces 33 to rise over the cam rods 63 formed on the adjustable seat 16. For example in Figure 5, the cam surface 33 illustrated of the cam member 22A forces the lower cam rod 63A down relative to the housing 2 of the DVCD (ie, since the shaft 21 is fixed vertically relative to the housing 2 by the ascending through the sides of the housing) and thereby forces the adjustable seat 16 downwardly inside the housing 2. Although not specifically shown in the drawings, it can also be understood how the cam member 22B acting on the upper cam stem 63B will force adjustable seat 16 up. The adjustment of the button 23 rotates to the shaft 21, cam elements 22 and thereby moves the adjustable seat 16 while the scale ring 24 provides a visual indication of the degree of movement of the cam member. In the illustrated embodiment, the graduation lines on the scale ring 24 are calibrated at the linear distance that the adjustable seat 16 moves with the rotation of the button 23. Through this mechanism, the cam elements 22 act to control with precision the up and down movement of the adjustable seat 16 in the inner housing chamber.

Although several structural components are located within the inner chamber 5 of the housing, there is in any case a fluid path around these components from the inlet 3 to the outlet 4. Once the fluid pressure at the inlet 3 causes the the non-return valve 45 opens and fluid is allowed to flow through the accumulator 10, there is a fluid path through the plug 46, through the circular base 64 of the adjustable seat, around the positioning mechanism 20 and through the exit 4. eration of the illustrated embodiments When employed in a positive displacement pump system, the DVCD 1 can be connected to the pump head assembly by threads or other mechanical means located on the lower outside of the casing 2 as suggested in Figure 2. With reference to Figure 5, the adjustable seat 16 is shown in the closed or lower position and completely restricts the movement of the accumulator 10 so that it remains closely located against the tapered inner side walls 9 of the carcass 2. In this position, it can be understood that when the pump head begins the discharge or pressurization part of its cycle, the fluid is pressurized at the inlet 3 of the DVCD assembly. In the illustrated embodiments, the fluid enters from the bottom through the inlet 3 and meets the bottom of the accumulator 10, which can not move in response to the fluid pressure that is being exerted on it because the seat adjustable 16 is in the fully lowered position. The pressurized fluid acts against the plug 46, which although the spring 47 deflects it to close, will open if the fluid pressure is sufficient to overcome the force of the spring 47.

Figure 6 illustrates the shutter 46 moving to the open position under fluid pressure. The performance of plug 46 allows the fluid to pass through the resulting space between the inner walls of the internal cavity 15 of the accumulator and the O-ring 49 of the plug, then through the openings or side ports 50 of the plug and through the open upper section of the shutter 46. Once the fluid moves through the shutter 46, it passes freely through the interior of the adjustable seat 16, positioning mechanism 20, and exits the DVCD assembly through the outlet 4. It will be understood that a Once the DVCD 1 is operating in a stable condition (for example, the interior is filled with the fluid being pumped), then all the fluid moved during the pump discharge cycle must flow into the DVCD 1 and a mass fluid equivalent (assuming a generally incompressible fluid) must exit through outlet 4.

Figure 7 is illustrated with the pressure removed from inside the DVCD 1 for reasons of clarity. It can be seen that the cam elements 22 (which are fixed to each other and therefore move as a single unit), have been rotated approximately 145 degrees counterclockwise, which also acts the adjustable seat 16 , causing it to move upwards and thereby creating a space between the adjustable seat 16 and the accumulator 10. Because no pressure is acting on the accumulator 10, remains located against the lower part of the side walls 9 of the internal chamber 5. In the same way, the shutter 46 remains seated against the lower part of the internal cavity 15 of the accumulator, due to the force applied against it by the spring 47. With the adjustable seat 16 in this "midway" position, when the pump head begins to apply pressure during a discharge part of its cycle, the fluid begins to apply pressure on and pushes through the interior of the pump. the input 3 of the DVCD, exerting pressure on the accumulator 10 and the shutter 46 simultaneously. The plug 46 is still held in its lowest position against the seat portion of the accumulator 10 by the spring 47. However, the movement of the fluid acts on the accumulator 10, causing it to move in a sliding manner upwards until it makes contact with the lower edge of the adjustable seat 16 (specifically the separator 17) as suggested in Figure 8. The shutter 46, which had remained seated when the accumulator 10 moved to its second position, now becomes the only available travel for the pressurized fluid and therefore the plug 46 acts up when the fluid pressure exceeds the force of the spring 47, again allowing the fluid to pass as previously described. In this sequence of operations, you can understand how a volume of fluid Vx discharged from the pump head is used or "borrowed" to maintain the accumulator 10 against the adjustable seat 16 prior to the actuation of the shutter 46. Once this volume of fluid enters the DVCD 1, any additional fluid will act the shutter 46 and it will flow through the plug 46 and will contribute to the fluid transferred out of the outlet 4 to the end of the discharge part of the reciprocating pump cycle. As previously described, at the end of the discharge part of the cycle, the fluid momentarily stops its flow. At this time, the pump head starts again its filling or suction part of its cycle. But unlike what was described when the accumulator 10 is completely restricted, now, before the fluid can start to flow into the pump through the suction retainer valve assembly 106 (see Figure 2), the accumulator 10 and the shutter 46 both react first to the instantaneous vacuum that marks the beginning of the refill by moving slidably downwards to their seated positions. When they move down together, they displace a volume of fluid, the same amount (Vi) that was used to act originally, back inside the pumphead assembly. During this part of the cycle, it can be understood that no new fluid will enter the pump head, rather only the fluid previously used to move the accumulator 10. Both the Accumulator 10 as the shutter 46 now returns to its downward and fully seated positions, as previously shown in Figure 7. At this time, no other fluid can enter the pump head assembly from the DVCD 1. Now, during the remainder of the pump cycle filling or suction part, new fluid will enter the pump head through the suction retention valve assembly 106, similar to the operation of the prior art device of Figure 1.

Through this description of Figures 7 and 8, it can be understood that, overall, less fluid was discharged through the DVCD 1 during the described cycle than when the accumulator 10 was restricted in the fully down position (ie, as in Figure 5) throughout the entire cycle. Once the accumulator 10 is not completely restricted, a quantity of fluid is not filled during the suction cycle, since the accumulator moves between its set and unset positions, and then returns to its original position. In essence, the pump displaces a combination of fluid and solid, the difference being in the volume of fluid Vi required to displace the accumulator 10, which travels through the precise distance allowed by the adjustable seat 16. At the pump head it is therefore not allowed to fill that volume of fluid during the suction cycle. The production overall pump is reduced by the displaced volume.

Figures 9 and 10 illustrate cam elements that have been rotated an additional 180 degrees counterclockwise to their maximum rotational position. At this point, both cam elements are prevented from moving further because the indentation on the curved face 34 on the cam surfaces has been engaged with the cam rods 63. As previously described, this additional rotation of the cam elements 22 additionally slidably acts the adjustable seat 16, causing it to move further upwards and thereby creating a larger space between the adjustable seat 16 and the accumulator 10. All the movements and actions are as described previously with reference to Figures 7 and 8, except that now the accumulator 10 is allowed to move a maximum distance and excludes the movement of a larger volume V2 through the outlet 4. From the above description, it will be understood that the elements of cam 22 can be rotated to any position, causing the adjustable seat 16 to vary from fully lowered to fully raised, and the accumulator 10 to move therefore an adjustable amount of fluid when moving in both directions in response to the pressure or vacuum created by the cycles of the pump head assembly.

The experts in the field will easily understand that the dimensions of the DVCD 1, including the diameter of the internal chamber 5 of the housing and the accumulator 10, and the amount of travel allowed by the variation of the diameter of the cam element 22 in its largest and smallest dimensions, and possibly other parameters , will determine the maximum amount of fluid that can be subtracted from the output of a pump to which the DVCD 1 is connected. It is preferred that the DVCD 1 has a fully seated or closed position, in which the pump head has its maximum production and efficiency, and then a variable amount of fluid that can be subtracted from the pump output by adjusting the position of the accumulator within the DVCD 1.

Although certain specific embodiments of the DVCD 1 have been described in detail in Figures 1-10, the present invention includes many alternative embodiments. As an example, an alternative positioning mechanism 20 is shown in Figures 11 and 12. In this embodiment, as best seen in Figure 12, the adjustable seat 16A includes an elongated shank 85 having a central passage 86 and a threaded section. 87. The threaded section 87 will engage corresponding threads formed on the inner surface of the chamber 5 of the housing as suggested in Figure 12. Thus the rotation of the adjustable seat 16A in the counter-clockwise direction or clockwise will result in movement in it up or down inside the housing 2A and thereby adjusting the space that the accumulator 10 has to move inside the chamber 5 of the housing. One way to apply a torque to rotate the adjustable seat 16A is to form windows 52 for accessing the seat in the housing 2A (Figure 11) and seat pair holes 53 in the adjustable seat 16A. A bar or other tool will access the torque holes 53 through the access windows 52 and allow the adjustable seat 16A to be rotated. It will be understood that this embodiment differs from the previous embodiment by allowing the adjustable seat to be rotated directly around the axis of the device instead of indirectly using cam elements 22, as previously described.

Figure 12 also illustrates how the O-ring seal 27 with the backup seal 26 will prevent fluid from migrating around the upper end of the adjustable seat 16A and exhausting through the access window 52. In the same manner, a scraper seal 55 prevents fluid from migrating around the lower end of the adjustable seat 16A and exhausting through the access window 52. The fluid path in Figure 12 can be visualized when the fluid pressure at the inlet 3 exceeds the spring 47 of the shutter. The fluid flows through the obturator 46 as previously described, but can then flow directly to the inner of the passage of the rod 86 and then exit through the outlet 4. The housing 2A also differs from the previous embodiment in that it has a smaller lower section threaded on a larger upper section (see the overlap threads 56). As in the previous embodiment, an O-ring 8 is placed to effect a seal between the upper and lower sections of the casing 2A.

A further additional embodiment of the DVCD device is seen in Figures 13 to 16. Figure 13 illustrates how this embodiment has a volume control knob 223 located opposite the inlet 203 while the outlet 204 is formed on the side of the casing 2B. Figures 14 and 15 better illustrate how this embodiment of the DVCD forms the adjustable seat with a stem or shaft 215 with an inverted cup structure 225 on the lower end and the upper end being connected to the control button 223. The axis 215 goes to through the retaining nut 222 and threadably engaged with the nut 222, while the nut 222 is threadably coupled to the upper section of the housing 2B. A u-cup or unidirectional seal 219 is located between the balanced shaft 215 and the nut 222; an O-ring with support seal 217 is located between the shaft 215 and the inner side wall of the housing 2B; and an additional u-cup or unidirectional seat 216 is located at the point where the shaft 215 enters the open cavity of the casing 2B containing the inverted cup 225 of the adjustable seat.

The shaft 215 is considered a "balanced shaft" in the sense that it has its pressure bearing surfaces in multiple directions to neutralize the forces induced by the pressure tending to join their threaded surfaces. Figure 15 illustrates the balance support 220 on the axis 215 which is subjected to the internal fluid pressure of the DVCD through the central passage of the shaft 221 and the lateral passages of the shaft 224. Thus, when the pressure acts on the lower part of the accumulator 210 will tend to exert an upward force and potentially join the threads on the shaft 215, the pressure on the balance supports 220 will tend to exert a force in contra-sense, thereby reducing the tendency for the threads to join Figure 15 also illustrates the relief passage 227 which will bleed any pressure of the fluid escaping past the seal 216 and which would otherwise tend to adversely act on the inner side of the balance support 220.

The accumulator 210 is similar to that of other embodiments in that it includes a non-return valve formed by a shutter 246 that is deflected against the internal side walls of the accumulator by the spring 247. Similarly, the accumulator 210 has a scraper seal 255 and a ring toric 240 which engages the tapered inner side walls in the lower section of the shell 2B to form a seal when the accumulator 210 is in its lowest position.

Figure 16 illustrates the situation when the button 223 has been rotated to raise the adjustable seat and its inverted cup 225 to allow the accumulator 210 to move up from the lower part of the internal chamber of the housing after the application of pressure fluid at the inlet 203. When the fluid pressure is sufficiently increased to overcome the spring of the obturator 247, the fluid first flows around and through the obturator 246, through the openings 226 in the inverted cup 225 and finally out through the fluid outlet 204 as suggested by the fluid flow arrows in Figure 16. Thus, the embodiment of Figures 13 to 16 provides a configuration in which the inlet and outlet are in closer physical proximity and the dosage of the Volume control button is more distant from the input and output parts of the DVCD device.

Figure 17 illustrates another embodiment of the DVCD having a particular application (although not exclusive application) in conjunction with diaphragm pumps. As used herein, a "diaphragm pump" generally refers to a positive displacement pump that uses a combination of the alternative action of a flexible diaphragm (e.g., rubber, thermoplastic or Teflon) and valves suitable on both sides of the diaphragm (check valve, butterfly valves, clapper valves or any other form of shut-off valves) to pump a fluid. Figure 17 shows the actuator 100 as described above (e.g., U.S. Patent No. 8,087,345) which provides reciprocating movement to the plunger 325 of the DVCD 1. The diaphragm pump 350 is connected to the DVCD 1 (typically by bolts not shown in the Figures) on the opposite side of the actuator 100. It will be understood that the actuator 100 and the diaphragm pump 350 are primarily illustrated to demonstrate an operating environment in which this embodiment of the DVCD can be employed and is an embodiment of the invention. DVCD is not limited to a particular type of actuator or a particular type of pump. For example, alternatively electrically powered actuators or internal combustion actuators could be employed.

Figure 18 shows in greater detail the main components of this embodiment of the DVCD 1. The DVCD will generally comprise the housing 302 having the accumulator chamber 305 formed therein. Located within chamber 305 of the accumulator is the accumulator 310, which in this embodiment has the spring cavity 311 and the tapered front portion 312 which engages a similarly conical surface at one end of the accumulator chamber 305. The stop Adjustable 315 also docks with the camera of the accumulator 305. This adjustable stop embodiment 315 includes a button portion 316, stem 317 and stop surface 318. The stop surface 318 takes the form of an inverted cup defining a spring cavity 319 and having a perimeter surface which is configured to engage (ie, has a similar surface) with the corresponding perimeter surface on the accumulator 310. Naturally, the inverted cup is merely an example of the stop surface shape and alternative embodiments of the stop surface 318 could Take any number of different forms. A bypass mechanism 324 acts to divert the accumulator 310 away from the stop surface 318. In the example of Figure 18, the bypass mechanism is a conventional spring, but could be any other conventional bypass or future development device .

In the illustrated embodiment, the shank 317 of the adjustable stop 315 does not directly engage the walls of the accumulator chamber 305, but rather the external threads of a threaded bushing 322 engage with the walls of the accumulator chamber 305 and internal threads on the bushing 322 engage with the external threads on the shank 317. It can be easily recognized that this arrangement allows the rotation of the button 316 to move the stop surface 318 towards and away from the accumulator 310, thereby allowing the stop surface 318 to limit the range of movement of the accumulator 310. It will be understood that the adjustable stop 315 is only one way of adjusting the potential travel distance of the accumulator 310 and any other conventional techniques could be employed. or of future development. As a non-limiting example, the cam system seen in Figure 5 could be used in place of the adjustable stop seen in Figures 17-19.

The DVCD 1 further comprises a reservoir housing 303 that forms a reservoir space 306 for containing the actuating fluid that drives the diaphragm in the diaphragm pump 350. The actuating fluid could be any number of fluid that will operate the DVCD and the pump 350 as described herein, but an acceptable drive fluid is a conventional gear oil such as 15-30W. A vent plug 307 engages the reservoir housing 303 and allows the internal volume of the reservoir to be maintained at the (typically atmospheric) pressure of the external environment. It can also be seen that an inner passage 335 communicates with the space of the reservoir 306, the chamber of the accumulator 305 and the distribution passage 336, which in turn has an interface with the hydraulic pump 350. It is understood that the fluid flowing to the through these steps is the "drive fluid", which activates the diaphragm. The fluid directed to be moved by the pump (the "pumped fluid") is isolated on the opposite side of the diaphragm and passes through an opposite pair of check valves (not shown in the drawings).

Figure 18 also illustrates how the plunger 325 extends through the space of the tank 306 and into the interior of the inlet passage 335. The illustrated embodiment of the plunger 325 further includes the internal passage 326 that opens at the end of the plunger 325 (it is say, it is in fluid communication with the internal passage 335) and one or more side holes or "absorption holes" 327 that extend through the plunger 325 and are in fluid communication with the internal passage 326. It will be understood that the fluid under pressure in the inner passage 335 is acting on the front of the accumulator 310 that through the distribution passage 336 and openings in the perforated plate 351, on the diaphragm 352. The pressurized fluid in the inner passage 335 will also act on the purge screw 330 through purge passage 337. In this embodiment, purge screw 330 is a manually operated seat or ball type purge screw, which is pre-set. I have to purge any air from the system in preparation for normal operation. Another step seen in Figure 18 is a bypass path 304 that extends between the accumulator chamber 305 and the reservoir space 306, allowing any fluid which escapes above the accumulator 310 returns to the space of the tank 306.

In operation, the plunger will move alternately between two positions, the position of the top dead center and the position of the bottom dead center. The top dead center positions refer to the end of the suction stroke as suggested in Figure 18 and the position of the bottom dead center refers to the end of the discharge path as seen in Figure 19. Figure 17 illustrates the plunger 325 at the end of the suction stroke, with the main drive piston 109 of the actuator 100 in its raised position. As seen in Figure 18, this places the end of the plunger 325 within the interior passage 335, but the suction hole 327 on the outside of the interior passage 335 and in fluid communication with the reservoir space 306. In this position, the actuating fluid is equalized through the suction holes 327, internal passage 326 and fills the inner passage 335 due to the hydrostatic pressure together with a slightly negative actuating pressure resulting from the vacuum created when any extra fluid is pressed between the plunger and the interior passage 335 and out through the suction holes 327 once they release the entry of the entrance passage and make its way into the interior of the reservoir under ambient conditions. In the discharge path, the drive piston 109 moves the plunger 325 into the interior of the inlet passage 335 as suggested in Figure 19. After the suction holes 327 move into the inlet passage 335, the narrow tolerances within the walls of the inlet passage substantially prevent the fluid from in the inlet passage 335 it escapes back to the tank 306. In this way, the pressure on the fluid in the inlet passage 335 increases. Similar to other embodiments described above, the accumulator 310 is capable of moving up against the spring force 324 if the fluid pressure is sufficiently high. Therefore, a certain amount of fluid volume can be directed into the accumulator chamber 305, thereby reducing the pressure that would otherwise act on the diaphragm 352 and the displacement to which the diaphragm 352 will be subjected. Naturally , the pressure acting on the diaphragm 352 and its displacement affect the pressure and volume of the pumped fluid moved through the diaphragm pump 350. Therefore, to the extent that the accumulator 310 can be moved upwards, will move less fluid pumped by the diaphragm pump 350. Obviously, if the adjustable stop 315 is screwed all the way until the stop 315 presses the accumulator 310 against the bottom of the accumulator chamber 305, then no fluid will be diverted to the interior of the accumulator chamber during the travel of discharge. When the plunger 325 is removed in the next suction stroke, the spring 324 acts to return the accumulator 310 to its fully seated position in the accumulator chamber 305 as seen in Figure 18.

In the illustrated embodiment, the accumulator 310 lies within the cavity of the accumulator 305 with sufficiently close tolerances so that a hydraulic piston sealing effect is achieved. However, other sealing techniques could be used in alternative, non-limiting examples that are mechanical seals (eg, O-rings) and labyrinth seals. As described above, any fluid that escapes above the accumulator 310 can be finally returned to the space of the reservoir 306 through the bypass path 304. It will be understood that in many embodiments, it will be relatively fine adjustments of the accumulator 310 that will affect the amount of fluid acting against the diaphragm 352. For example, in one embodiment, the volume of fluid allowed inside the accumulator chamber 305 is between about 1 ml and about 100 ml. Obviously in other embodiments, the volume of fluid allowed in the accumulator chamber 305 could be much greater or even smaller than this range.

As suggested by Figure 17, this embodiment of the DVCD / pump system can be viewed as separate in three discrete and separable sections that are screwed (or connected in another way together). Thus, the pump forms a first separable section A, the accumulator chamber is formed into a second separable section B and the shell of the reservoir is formed into a third detachable section C. Naturally, other embodiments could be formed with less or more separable sections.

Figures 20 and 21 illustrate a slight variation of the embodiments of Figures 17 to 19. Figure 20 is an end view of a DVCD / pump combination showing the section line for the cut view in Figure 21. In this embodiment, plunger 325 is solid as seen in Figure 21, ie it does not have an internal passage 326 or suction holes 327. However, this embodiment additionally includes a non-return valve (e.g. a check valve) 340 located at the interface with the reservoir space 303 and supplies fluid to the diaphragm 352 through the relief passage 341, ie, the direction of flow through the non-return valve is from the reservoir space 303 to the diaphragm 352. embodiment operates in a manner similar to that of Figures 17-19, except that it is not based on suction holes for filling fluid into the internal passage during the suction stroke. Instead, when the plunger 325 moves away from the diaphragm 352 during the suction stroke, any A tendency to create a vacuum in the inlet passage 335 is alleviated by the ability of the fluid to flow from the reservoir space 303, through the check valve 340 and relief passage 341 and around the diaphragm 352, and eventually to the passage of inlet 335 (assuming that a volume of fluid flow is necessary to relieve the vacuum produced by the retreating plunger). Naturally, the suction holes 327 and the check valve 340 are merely two example techniques for equalizing pressures throughout the system during operation and those skilled in the art will visualize many other techniques that could also be considered within the scope of the present invention. .

Many other embodiments of the invention can be conceptualized by considering the functional components of the DVCD. For example, another embodiment is a DVCD in which a solid component is moved in response to the pressure exerted by the fluid within a positive displacement pump head during its discharge cycle, and is subsequently subsequently replaced prior to the refill cycle. the pump, thereby subtracting a part of the fluid that had otherwise been discharged. This DVCD can have a solid component that is adjustable. A further embodiment of the DVCD replaces and acts as the discharge check valve of a positive displacement pump, in which the component The solid moves as described immediately before, in concert with the components of the normal check valve (for example a ball or plug). In this embodiment, the solid component is also adjustable.

Those skilled in the art will recognize that the described embodiments of the DVCD 1 directly control the dosing volume without disturbing the mechanical movement of the actuator. Instead, the DVCD 1 directly varies the dosing volume at the delivery point by controlling the "apparent size" of the dosing chamber. The DVCD 1 makes a precisely controlled part of fluid, which would normally be discharged during the discharge part of the pump cycle, be "borrowed" immediately before it is delivered, then "paid" or returned to the dosing immediately before the filling or suction part of the dosing cycle. The DVCD 1 allows a controllable solid component to move "in place" of a variable part of the fluid that would otherwise have been discharged. This solid component moves a controlled distance in response to the hydraulic pressure from the discharge cycle, just before the fluid discharge, and then replenishes itself in response to the vacuum pressure just prior to the filling or suction cycle of fluid, returning the volume displaced to the pump. It is totally passive, reacting simply to the discharge and refill cycles, and involves only a moving part in addition to what would exist in a non-controllable pump. In any case, not all embodiments of DVCD 1 need to have the functionalities described above and embodiments lacking such functionalities are also intended to fall within the scope of the present invention.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (81)

1. A volume control device comprising: a. a housing having an entry passage, an exit passage and an internal chamber communicating with the entry and exit passages; b. an accumulator movably located within the internal chamber and substantially in conformity with the walls of the internal chamber wherein the accumulator includes an internal passage allowing the flow of fluid therethrough; c. a non-return valve located in the internal passage of the accumulator where the valve is diverted to a closed position; d. an adjustable seat located inside the inner chamber of the housing between the accumulator and the outlet passage of the housing; and. a positioning mechanism that couples the adjustable housing and seat by means of which the position of the adjustable seat within the internal chamber of the housing can be fixed in an adjustable manner.

2. The volume control device according to claim 1, wherein the accumulator is sealed against a lower part of the internal chamber and the internal passage of the accumulator is substantially aligned with the inlet passage. of the housing.

3. The volume control device according to claim 1, wherein the valve within the accumulator is a seat valve with a spring that deviates it to the closed position.

4. The volume control device according to claim 1, wherein a first part of the adjustable seat holds the accumulator against a lower part of the internal chamber of the housing.

5. The volume control device according to claim 4, wherein a second position of the adjustable seat allows the accumulator to travel a first distance within the internal chamber of the housing.

6. The volume control device according to claim 5, wherein a third position of the adjustable seat allows the accumulator to travel a second greater distance within the internal chamber of the housing.

7. The volume control device according to claim 1, wherein the positioning mechanism comprises at least one cam element that rotates within the internal chamber of the housing.

8. The volume control device according to claim 6, wherein the accumulator is free to travel the first or the second distance subjected only to the sealing friction between the accumulator and the wall of the internal chamber of the housing.

9. The volume control device according to claim 7, wherein the positioning mechanism comprises two cam elements that engage with cam rods on the adjustable seat.

10. The volume control device according to claim 1, further comprising a first seal located between the accumulator and a wall of the internal chamber of the housing and a second seal located between the adjustable seat and the wall of the internal chamber of the housing .

11. The volume control device according to claim 1, wherein the positioning mechanism includes an external control surface to the housing.

12. The volume control device according to claim 11, wherein the positioning mechanism includes a screw element and the control surface is a gripping surface on one end of the screw element.

13. The volume control device according to claim 1, wherein the non-return valve allows flow in the direction of the inlet passage to the outlet passage.

14. The volume control device according to claim 1, wherein the positioning mechanism it comprises mating threaded surfaces on a part of the wall of the internal chamber of the housing and on the adjustable seat.

15. The volume control device according to claim 14, wherein the adjustable seat includes a threaded shank in line with the inlet passage.

16. The volume control device according to claim 1, wherein the accumulator has a first larger end and a second smaller end, and said second smaller end slides into an opening in the adjustable seat.

17. The volume control device according to claim 16, wherein the second end slides freely within the adjustable seat.

18. The volume control device according to claim 1, wherein the components located inside the housing consist essentially of the accumulator, the adjustable seat and the positioning mechanism.

19. The volume control device according to claim 1, wherein the positioning mechanism comprises means for altering the position of the adjustable seat within the housing to allow a different degree of travel within the housing by the accumulator.

20. An alternative pump system with control of adjustable volume, the system comprising: to. an alternative pump that has a fluid inlet that allows a fluid to enter the pump during an intake cycle and a fluid outlet that allows fluid to leave the pump during a discharge cycle; Y b. a volume control device in fluid communication with the pump output, the control device comprising: i. a housing having an entry passage communicating with a pump outlet, an exit passage and an internal chamber communicating with the entry and exit passages; ii. an accumulator movably located within the internal chamber and having at least one surface substantially in conformity with the walls of the internal chamber wherein the accumulator includes an internal passage allowing the fluid to flow therethrough; iii. a valve located in the internal passage of the accumulator where the valve is diverted to a closed position; iv. an adjustable seat located inside the internal chamber of the housing; v. a positioning mechanism that engages the adjustable seat and shell by means of which the seat position can be adjusted in an adjustable way adjustable inside the inner chamber of the housing.

21. A volume control device comprising: a. a housing having an entry passage, an exit passage and an internal chamber communicating with the entry and exit passages; b. a volume control means for controlling a volume of fluid within the internal chamber, the volume control means further including an internal passage allowing the flow of fluid therethrough; c. means for controlling the flow direction to allow fluid flow in one direction, the flow direction control means being located in the internal passage of the volume control means and being diverted to a closed position; d. a seat means for adjustably positioning the volume control means within the inner chamber of the housing, the seating means being between the volume control means and the outlet passage of the housing; and. a positioning means for adjustably fixing the position of the seating means within the internal chamber of the housing.

22. A volume control device comprising: a. one entry step and one exit step; b. an accumulator located in an accumulator chamber in which the accumulator chamber is in communication for fluids with the entrance passage; c. a positioning mechanism by means of which the position of the accumulator in the accumulator chamber can be set in an adjustable manner; d. a non-return valve located in a non-return valve chamber in which the chamber of the non-return valve is in communication for fluids with the inlet passage; Y and. in which the chamber of the check valve is in communication for fluids with the outlet passage and the check valve is diverted to a closed position of the inlet passage from the outlet passage.

23. The volume control device according to claim 22, wherein a passage of the accumulator provides a fluid connection between the outlet passage and the accumulator chamber.

24. The volume control device according to claim 22, wherein an adjustable seat holds the accumulator against one end of the accumulator chamber.

25. The volume control device according to claim 24, wherein a first adjustable seat position allows the accumulator to travel a first distance inside the accumulator chamber and a second adjustable seat position allows the accumulator to travel a second distance within the accumulator. accumulator chamber.

26. The volume control device according to claim 22, wherein the non-return valve is a seat valve with a spring that biases it to the closed position.

27. The volume control device according to claim 22, further comprising a first seal located between the accumulator and a wall of the accumulator chamber.

28. The volume control device according to claim 22, wherein the non-return valve allows flow in the direction of the inlet passage to the outlet passage.

29. The volume control device according to claim 24, wherein the positioning mechanism comprises matching threaded surfaces on a part of the wall of the accumulator chamber and on the adjustable seat.

30. The volume control device according to claim 22, wherein the accumulator chamber, the non-return valve chamber, the inlet passage and the outlet passage are formed in a single unitary housing.

31. The volume control device according to claim 22, wherein the accumulator chamber and the non-return valve chamber are formed in separate bodies and external conduits connecting the inlet passage and the exit passage to the accumulator chamber and the anti-return valve chamber.

32. The volume control device according to claim 1, wherein the accumulator substantially in conformity with the walls of the internal chamber includes a seal located between the walls and the accumulator.

33. A volume control device comprising: a. a housing having an entry passage; b. an accumulator located in an accumulator chamber in which the accumulator chamber is in fluid communication with the inlet passage; Y c. a positioning mechanism by means of which the path of the accumulator in the accumulator chamber can be adjusted.

34. The volume control device according to claim 33, wherein the positioning mechanism includes a stop surface configured to be coupled to the accumulator.

35. The volume control device according to claim 34, wherein the positioning mechanism includes a threaded rod fixed to the stop surface and allowing the adjustment of the stop surface towards the accumulator and separating therefrom.

36. The volume control device according to claim 34, wherein a bypass mechanism is located between the accumulator and the stop surface.

37. The volume control device according to claim 33, wherein the input passage communicates with a fluid reservoir containing a driving fluid.

38. The volume control device according to claim 37, wherein a plunger communicates with the reservoir and pressurizes the driving fluid in the inlet passage.

39. The volume control device according to claim 38, wherein the plunger includes an internal passage oriented in a longitudinal direction and a lateral outlet communicating with the internal passage.

40. The volume control device according to claim 39, wherein the operating stroke of the plunger moves the lateral outlet from the interior of the reservoir to the interior of the inlet passage.

41. The volume control device according to claim 37, wherein a bypass fluid path extends from the accumulator chamber to the fluid reservoir.

42. The volume control device according to claim 38, wherein a diaphragm pump communicates with the inlet passage and the operation of the plunger increases the pressure on the actuating fluid acting against a diaphragm in the pump.

43. The volume control device according to claim 42, wherein the diaphragm pump includes a perforated plate.

44. The volume control device according to claim 38, wherein the accumulator moves along a first axis and the plunger moves along a second axis substantially perpendicular to the first axis.

45. The volume control device according to claim 33, wherein the accumulator chamber is in the housing.

46. The volume control device according to claim 33, wherein a non-return valve located in a non-return valve chamber in which the non-return valve chamber is in communication for fluids with the inlet passage.

47. The volume control device according to claim 46, wherein the chamber of the check valve is in communication for fluids with an outlet passage in the housing and the check valve is diverted to a closing position of the inlet passage from the exit step.

48. The volume control device according to claim 47, wherein a passage of the accumulator provides a connection for fluids between the output step and the accumulator chamber.

49. The volume control device according to claim 47, wherein an adjustable seat holds the accumulator against one end of the accumulator chamber.

50. The volume control device according to claim 49, wherein a first adjustable seat position allows the accumulator to travel a first distance inside the accumulator chamber and a second adjustable seat position allows the accumulator to travel a second distance within the accumulator. accumulator chamber.

51. The volume control device according to claim 47, wherein the non-return valve is a seat valve with a spring that deviates it to the closed position.

52. The volume control device according to claim 47, further comprising a first seal located between the accumulator and a wall of the accumulator chamber.

53. The volume control device according to claim 47, wherein the non-return valve allows flow in the direction of the inlet passage to the outlet passage.

54. The volume control device according to claim 49, wherein the positioning mechanism comprises matching threaded surfaces on a part of the wall of the accumulator chamber and on the adjustable seat.

55. The volume control device according to claim 47, wherein the accumulator chamber, the non-return valve chamber, the inlet passage and the outlet passage are formed in a single unitary housing.

56. The volume control device according to claim 47, wherein the accumulator chamber and the non-return valve chamber are formed in separate bodies and external conduits connect the inlet passage and the outlet passage to the accumulator chamber and the check valve chamber.

57. A diaphragm pump system comprising: to. a diaphragm pump; b. a volume control device comprising: i. a housing having an inlet passage, the housing being fluidly connected to the diaphragm pump; ii. an accumulator located in an accumulator chamber in which the accumulator chamber is in fluid communication with the inlet passage; Y iii. a positioning mechanism by means of which the path of the accumulator in the accumulator chamber can be adjusted.

58. The volume control device according to claim 57, wherein the positioning mechanism includes a stop surface configured to engage the accumulator.

59. The volume control device according to claim 58, wherein the positioning mechanism includes a threaded rod fixed to the abutment surface and allowing the adjustment of the abutment surface towards the accumulator and separating therefrom.

60. The volume control device according to claim 58, wherein a deflection mechanism is located between the accumulator and the stop surface.

61. The volume control device according to claim 57, wherein the inlet passage communicates with a fluid reservoir containing a driving fluid.

62. The volume control device according to claim 61, wherein a plunger communicates with the reservoir and pressurizes the actuating fluid in the inlet passage.

63. The volume control device according to claim 62, wherein the plunger includes an internal passage oriented in a longitudinal direction and a lateral outlet communicating with the internal passage.

64. The volume control device according to claim 63, wherein a discharge path of the Plunger moves the lateral outlet from the inside of the tank to the interior of the entrance passage.

65. The volume control device according to claim 61, wherein a fluid path in derivation extends from the accumulator chamber to the fluid reservoir.

66. The volume control device according to claim 62, wherein the operation of the plunger increases the pressure on the actuating fluid acting against a diaphragm in the pump.

67. The volume control device according to claim 57, wherein the diaphragm pump includes a perforated plate.

68. The volume control device according to claim 62, wherein the accumulator moves along a first axis and the plunger moves along a second axis substantially perpendicular to the first axis.

69. The volume control device according to claim 61, wherein the diaphragm pump forms a first separable section, the cavity of the accumulator is formed in a second separable section and the fluid reservoir forms a third separable section.

70. The volume control device according to claim 69, wherein the inlet passage is formed through the second and third separable sections.

71. A method of adjusting the flow of the fluid supplied by a pump comprising the steps of: to. connection of a fluid inlet for driving the pump to an outlet of a volume control device, wherein the volume control device includes: i. a housing having an inlet passage, the housing being connected fluidly to the pump inlet; ii. an accumulator located in an accumulator chamber in which the accumulator chamber is in fluid communication with the inlet passage; Y iii. a positioning mechanism by means of which the path of the accumulator in the accumulator chamber can be adjusted; b. advancing a plunger within the inlet passage, thereby increasing the fluid pressure in the accumulator and the input of pump drive fluid.

72. The fluid adjustment method according to claim 71, wherein the positioning mechanism includes a stop surface configured to be coupled to the accumulator.

73. The fluid adjustment method according to claim 72, wherein a bypass mechanism is located between the accumulator and the stop surface.

74. The fluid adjustment method according to claim 72, wherein the inlet passage communicates with a fluid reservoir containing a driving fluid.

75. The fluid adjustment method according to claim 71, wherein the plunger includes an internal passage oriented in a longitudinal direction and a lateral outlet communicating with the internal passage.

76. The fluid adjustment method according to claim 75, wherein a discharge path of the plunger moves the lateral outlet from the interior of the reservoir to the interior of the inlet passage.

77. The fluid adjustment method according to claim 76, wherein a bypass fluid path extends from the accumulator chamber to the fluid reservoir.

78. The fluid adjustment method according to claim 71, wherein the operation of the plunger increases the pressure on the actuating fluid acting against a diaphragm in the pump.

79. The fluid adjustment method according to claim 71, wherein the accumulator moves along a first axis and the plunger moves along a second axis substantially perpendicular to the first axis.

80. The fluid adjustment method according to claim 74, wherein a non-return valve communicates between the reservoir and a diaphragm of the pump, the check valve being oriented to allow flow from the reservoir, passing the diaphragm, and into the passage input of the volume control device.

81. The fluid adjustment method according to claim 71, wherein the accumulator moves along a first axis and the plunger moves along a second axis substantially perpendicular to the first axis.