MXPA01000966A - Fluid vacuum safety device for fluid transfer systems. - Google Patents

Abstract

A safety device (50) for use in a fluid transfer system having a pump (24) which draws water from a reservoir through one or more intake lines (10) each extending from an open end at the reservoir to the pump intake. The device analyzes negative pressure levels in the system and, upon detecting a negative pressure level being outside of a selected operational range, deactivates the pump (24) and triggers a vacuum breaker device to eliminate negative pressure in the system. The safety device may further activate alarm devices to indicate that the system has been deactivated.

Description

FLUID VACUUM SAFETY DEVICE FOR FLUID TRANSFER SYSTEMS BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a safety device for fluid transfer systems and, more particularly, to a safety device that can operate in response to the detection of a predetermined negative pressure level, in one or more lines of admission of a fluid transfer system, to eliminate a vacuum in it, whereby it removes a suction force in the open ends of the intake lines.

Description of Related Art Drowning is the second leading cause of unintentional damage related to the deaths of children 14 years of age and younger. While most drownings occur in swimming ponds, a surprising fact is that in many drownings, swimming ponds and hot tubs (both adults and children) the main reason is the water circulation system. In a typical pond, the circulation system includes a main suction intake line for the drain and at least one skimmer suction intake line, both of which are fed into a main intake line leading to a pump. A return line directs the flow of water back to the pond. Many people do not perceive the threat by the pond circulation system, which includes the admission of the main drain at the bottom of the pool, and the foam boxes along the side of the pool. However, if a person comes in contact with any of the suction intake lines of the circulation system (at any of the drain or skimmer admissions) that causes the suction intake to be covered or obstructed, the immense suction of the Pump forms an instantaneous seal between the open end of the suction intake line and the skin or clothing of the person. This can result if a person places his or her hand on the open end of the suction intake line or, as often happens with children, a person sits on the suction intake. In any case, the force necessary to pull and release them often exceeds 363 kilograms. Also, the damage that has been inflicted in a matter of a few seconds is horrible, usually permanent and sometimes fatal. If a person, especially a child, adheres to the suction admission of the main drain on the bottom of the pool, she usually drowns.

The only way to free a person adhering to the admission of a circulation system of this type, without causing severe injury or dismemberment, is to interrupt or disable the source of the suction force, that is, the pump. This can be done by interrupting the energy to the pump. However, even if the pump is stopped, a vacuum will remain on the intake side of the system, between the pump and the clogged end of the suction intake line. However, a victim may still be released with some assistance, causing minor injuries. Ideally, if the gap in the intake line can be eliminated quickly, after the victim has adhered to the admission, the victim will be released with little or no assistance and no injuries. In most cases, when a victim comes to adhere to an admission of a circulation system, typically in a swimming pool or hot tub, the rescuers fail to carry out the need to immediately stop the pump. Instead of this, in panic, people tend to go to the victim and try to pry them free. In rare cases, this is successful, and the injuries are often severe and permanent. Of course, there are also cases where there are no people present to rescue the victim. These situations are almost always fatal.

The imminent danger presented by fluid circulation systems of the type commonly found in swimming ponds, hot tubs, and the like, has been around for a long time. No attention, if any, has been given to provide a satisfactory solution to this deadly problem, which exists in each swimming pool, hot tub, as in all other circulation systems, in which a fluid is withdrawn from a deposit through one or more suction admissions by a pump. Therefore, there has been and remains an urgent need to provide an effective remedy to prevent death and injury to these otherwise unfortunate victims, who come to join unexpectedly by sucking upon the admission of a fluid circulation system.

SUMMARY OF THE INVENTION The present invention is directed to a device for use in a fluid transfer system, of the type that includes at least one pump, which sucks water from a reservoir, through one or more intake lines, which they extend from an open end to the tank to a pump intake. The primary purpose of the invention is to save lives and properties, relieving the intense vacuum that is formed when one or more suction inlet gates of a fluid circulation system, assisted by a pump, becomes clogged. The safety device includes elements to analyze the negative pressure levels detected in the Eluido transfer system. When detecting a negative pressure level that is outside a normal operating range, the vacuum pressure relief elements are actuated, to eliminate the negative pressure in the system,. thus removing the suction at the open ends of the intake lines. The device can also disable the pump, closing it, by detecting the abnormal level of negative pressure. Warning devices, including audible and visible alarms, may be provided to indicate that the operation of the fluid transfer system has been interrupted. This is especially useful in alerting users to the possible occurrence of an obstruction of the intake lines by a person or object, and the need to inspect and readjust the device, before reactivating the fluid transfer system. Other options may also be available, which include pump shutdown, remote alarms, visual indicators, and the like.

OBJECTIVES AND ADVANTAGES OF THE INVENTION With the foregoing in mind, it is a primary object of the present invention to provide a safety device for use in a fluid transfer / circulation system, in which this device is structured to eliminate negative pressure in the system, by detecting a level of this negative pressure outside of a selected operational range, thus removing the suction at the open ends of the intake lines. It is a further object of the present invention to provide a safety device, which is useful in fluid circulation systems of swimming ponds, hot tubs and the like, to prevent death and injury to people or animals, which arrive to adhere by suction to the intake openings of the system. It is still another object of the present invention to provide a safe, reliable and relatively inexpensive safety device for easy installation to existing fluid transfer / circulation systems and which is structured to eliminate negative pressure in the system. detect a negative pressure level outside a predetermined range, thus removing the suction at the open ends of the intake lines. It is still a further object of the present invention to provide a reliable, relatively inexpensive safety device for use in a fluid transfer / circulation system, of the type that includes at least one pump, which sucks water from a reservoir, to through one or more intake lines, where this device is structured to deactivate one or more pumps and also eliminate the negative pressure in the system, upon detecting a predetermined level of negative pressure in the system, outside a predetermined interval. It is still a further object of the present invention to provide a security device, as described above, which further includes warning devices, such as, but not limited to, audible and visible alarms, to indicate that the security device has been powered , to eliminate negative pressure in the intake lines of a fluid transfer system. These and other objects and advantages of the present invention will be more readily apparent with reference to the following detailed description, taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the nature of the present invention, reference should be made to the following detailed description, taken in relation to the accompanying drawings, in which: Figure 1 is a block diagram, which illustrates the primary components of the security device and their functional interrelation, according to a first preferred embodiment of the present invention; Figure 2 is a circuit diagram of the I-a sensor mode of Figure 1; Figure 3 is a circuit diagram of the detector of the embodiment of Figure 1; Figure 4 is a circuit diagram of the control and replacement components of the embodiment of Figure 1; Figure 5 is a schematic diagram illustrating the interconnection of the safety device of Figure 1 to a fluid transfer / circulation system of the type commonly used in swimming ponds and hot tubs; Figure 6 is an elevation view, in partial section, illustrating a typical fluid circulation system for circulating fluid in a reservoir, such as a swimming pool, hot tubs or the like, which shows the safety device of the present invention installed in line on a main suction intake line of the system, between the intake of the system pump and the suction intake openings, in the swimming pool: Figure 7 is an elevation view, in partial section, illustrating an alternative embodiment of the security device of the present invention; Figure 8 is a top plan view of the security device of the embodiment of Figure 7; Figure 9 is an elevation view of the security device of the embodiment of the Figure; and Figure 10 is a top plan view, taken alone, in the plane of line 10-10 of Figure 7; Similar reference numbers refer to similar parts through the various views of the drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is directed to a safety device 50 for fluid vacuum, for use in a fluid circulation system, assisted by a pump, in order to relieve an intense vacuum that is formed in the system, when one or more suction admission doors of the circulation system, become obstructed. Referring to Figure 6, it shows a typical fluid circulation system, of the type commonly found in swimming ponds and in hot tubs. A water reservoir W is contained within a structure, having side walls 2 and a bottom 4. A main drain 6, having a cover grid, is provided at the bottom 4. At least one foaming box 8 is provided, along one or more of the side walls 2, at the level of the surface del agua, SL. An intake line 10 of the suction of the drain goes from the main drain 6 to a main suction intake line 20. A suction admission line 12 of the frother has an open end 13 in the skimmer case 8, which is kept below the level of the water surface, SL. This intake line 12 of the suction of the frother feeds into the main intake line 20. This main intake line 20 is directed to a pump 24, which may have a screen trap 26 connected to the 10 main intake line, just before the intake of the pump 24. A main outlet line 28 leads to a filter 30. One or more return lines 32 extend from the filter 30 back to the water tank, to return the water that is circulated through the system, back to 15 reservoir W. Figure 6 shows the safety device 50 of the fluid vacuum, properly installed in line along the intake line 20 of main suction of the circulation system, before the admission of the pump 24 20 and the screen trap 26. If an object or a person is caused to adhere on one of the open ends of the suction admissions, such as the open end 13 of the suction inlet 12 of the skimmer, the drain plate 7 or, if this drainage plate is removed, the line of 25 admission 10 of drainage suction, in drainage The main vacuum 6, a vacuum will develop instantaneously through the intake lines, which include the main suction intake line 20. This safety device 50 of the fluid vacuum is designed to react in this situation, to immediately eliminate the vacuum in the system and, therefore, the suction force at the open ends of each suction intake line, which .uye admission of suction 13 of the skimmer and admission 6 of the main drain. Upon reaching a predetermined vacuum level, which happens very rapidly, when one of the admissions becomes obstructed, the safety device 50 of the fluid vacuum causes the air of the atmosphere to be rapidly introduced into the main intake line 20. and through the other intake lines, thus removing all the suction force at the open intake suction ends 13 and 16 in the tank. The air introduced into the system interrupts the first of the pumps 24, thus eliminating any further source of suction. Referring to Figures 1 to 5, a first preferred embodiment of the present invention is shown. The main components of the safety device 50 of the fluid vacuum are shown in Figure 1 and include a sensor circuit 120, which detects the level of vacuum in the fluid circulation system. The output of the sensor circuit 120 is applied to an analyzer circuit 130, which allows the selective adjustment of a particular vacuum level (a predetermined vacuum level) by the control circuit 140, which will define a trip point or emergency condition in the system. The output of the analyzer circuit is applied to the control circuit 140 for the process and further control of the operational relays or contactors 150. An isolated power supply 160 provides the voltage for the circuit system. The sensor circuit 120 is illustrated in Figure 2 and uses a strain gauge 122 (SG1) to detect the vacuum in the return line 20 of the pump. The four internal elements, R1, R2, R3 and R4, in the stress gauge 122, form a bridge circuit. At 0 cm of the vacuum pressure of the mercury, the bridge circuit 122 is balanced and the bridge output is 0, with the joint of R1 / R3 being equal to the joint of R2 / R4. The output of the joints is applied to the inputs of II, an operational amplifier 124. When the bridge is balanced, the output of the operational amplifier 124 is approximately half the power supply voltage. As the vacuum increases, the bridge becomes unbalanced and the jungles of R1 / R3 and R2 / R4 change the voltage levels in a direct relationship to the level of vacuum pressure in the system. This small change in voltage is amplified by the operational amplifier 124 and provides a level, which can be used, for the circuit 130 of the analyzer. The resistor R5 adjusts the minimum gain of the operational amplifier, while the adjustable resistor R6 sets the maximum gain. The ability to control gain is necessary, because there are wide variations of the vacuum levels found in different systems. In a preferred embodiment, operational amplifier 124 is of type 741 IC. The analyzer circuit 130, as shown in FIG. 3, contains a ladder network 132 of the resistor, composed of the resistors R1-R9. Both Rl and R9 are variable resistors. The resistors R2-R8 are all of equal value. In this way, a high point and a low comparator point can be adjusted by means of resistors R9 and Rl, respectively, leaving six other comparator points, also valued, between the high and low points. The voltages derived from this ladder network 132 apply to the positive inputs of circuits 134 (IC1) and 136 (IC2) of the comparator. The output of the sensor circuit 120 is applied to the negative inputs of the comparators 134 and 136. The normal output of the sensor circuit 120 is about half the supply voltage. R9 is adjusted so that the positive input of the comparator 136 is slightly greater than the steady state output of the sensor circuit 120. Under these conditions, the comparators are in a displaced state and their outputs are high. As a vacuum is applied to the sensing circuit 120, the output voltage will increase in a linear fashion. The voltage increase is applied to the negative inputs of all eight comparator circuits of 134 and 136. As the voltage increases, the first comparator on the board of R8 and R9 goes into conduction. As the increase continues, each of the comparators will act in a similar manner. If the voltage continues to increase to its designed maximum, all eight comparator circuits will be driving. Any comparator that is conductive will have a low output. The comparators have an open collector output circuit and each is connected to the power supply 160 by means of a light-emitting diode, LED 138, and series-limiting resistors, 139 (RP1). This condition will cause the LED connected to each individual comparator to illuminate and indicate the level of the vacuum reached. The output of each comparator is also connected to an SPST switch, contained in the bank of switches 137 (SW1). These switches each represent one of the eight circuits of the comparator. The switch is connected to the comparator, which represents the preselected vacuum level at which the corrective action is desired, is placed in the ON position, and the comparator output is connected to the output line of the analyzer. In this way, an alarm condition is achieved, when the previously established vacuum level is obtained. The simple switch that is selected as the travel level will always be illuminated, since the LED, which corresponds to the selected level, is connected to that switch and the current will flow through the resistor contained in 139, the LED contained in 138, the switch contained in 137, and the circuitry for clamping the input voltage, contained in the control circuitry 140, described below. The sensor circuit 120 and the analyzer circuit 130 require a power supply voltage, which is slightly greater than that required for the control circuitry 140. This requires that the output of the analyzer circuit 130 be held at the maximum voltage level. input allowed by the circuit system of the control circuit 140. A clamping diode is used at the input of the control circuit 150 and completes the current path that allows illumination of the selected switch in the bank 137 of switches.

Referring to Figure 4, the control and relay circuitry 140 is shown, according to the first preferred embodiment of the fluid vacuum safety device 50. The input signal to the control circuitry 140 is the output of the analyzer circuit and is applied to an inverter 141, to generate a true or high signal under an alarm or condition out of normal. The output of the inverter 141 is connected to a "Y" ("AND") gate with three inputs, 142. The The second input to this "Y" gate 142 is the output Q 'of the service timer 143. The service timer 143 is a type 555 timer and is set by the momentary activation of the service switch 144. When this switch 144 is activated, the adjustment input 15 the chronometer 143 starts the chronometer cycle. This causes the Q 'output of the FALSE chronometer 143 ("FALSE") and applies a FALSE output to the "Y" gate 142. In this way, any signal from the analyzer's circuitry 130 is denied, while in the mode of service.

When the service is completed, the service person will momentarily activate the "SERVICE RESET" switch 145, which will activate the timer 143, the reset circuitry, and restore normal conditions to the system. If switch 145 is not pressed / activated, 25 the 143 timer will have a time out and the operation -.jnl-A ^ -. normal will be restored after a predetermined period of time. The third entrance to the "Y" gate 142 is connected to another stopwatch 146, which is also a type 555 timer. This particular timer 146 is started when the power is connected and applied to the device 50. The output Q1 of this stopwatch 146 keeps the "Y" gate 142 shifted for a short duration, when the The system starts up initially, in order to allow the pump of the fluid circulation system to cebcirse. At the end of this duration, two of the "Y" entries are in the true state. This is a normal operation. If an alarm condition must be found, the alarm input to gate "Y" will be true. With all three true inputs, the output of the gate "Y" 142 goes true and activates the adjustment input to the latch 147. This latch 147 remains in a set state until it is manually reset by means of a reset reset switch 148. alarm. When the latch 147 is adjusted, the relay 149 is activated and the normally closed (N / C) contacts open. This drop in energy on contact allows the pump of the circulation system to operate. At the same time, the normally open (N / O) contacts close and supply power to operate the vacuum interrupter 170 (see Figure 5), which will allow the release of any retained object to the open ends of the intake lines (return lines) leading from the reservoir to the pump 24. Once this happens, the pump 24 can not restart until the switch 148 of the alarm reset is activated. It should be noted at this point, that the device 50 can be configured with additional relay contacts, to allow the use of various warning devices and indicators, which are activated at the previously established vacuum pressure level (alarm condition). Referring to Figure 5, the device 50, according to the first preferred embodiment, is wired along with a vacuum switch 170 to the other components of a fluid circulation system. The diagram of Figure 5 is representative of a preferred configuration of components for use in the fluid circulation system of swimming ponds and hot tubs. In Figure 5, the safety device 50 of the fluid vacuum is shown wired to the vacuum switch 170 and other components. When the system timer 180 is active, the power is applied to the transformer 190, which supplies a low AC voltage to the safety device 50. A side of the low AC voltage is also supplied on contacting 200 and the vacuum switch 170 . If the conditions are normal, the low voltage AC circuit will be completed upon contacting 200 which will allow the motor 210 of the pump 24 to operate. Once the initial period of time of starting the pump is completed, the safety device 50 monitors the operating conditions. If a condition displaced from normal is found, this safety device will interrupt the circuit to contactor 200 and complete the circuit to vacuum interrupter 170, thus introducing air from the atmosphere into the suction intake lines (return lines) of the system and will eliminate the vacuum pressure between the pump 24 and open the ends of the suction intake lines. This state will be maintained until the device 50 is manually reset, after the condition has cleared to normal. With the addition of additional contacts, other indicators or warning devices can be added. Referring now to the remaining drawing figures, the fluid vacuum safety device is shown, according to an alternative embodiment, and is indicated as 50 '. This security device 50 'includes a base unit 52, defined primarily by an inverted T-section, formed of PVC, having a main passage 54 defined by the bottom of the inverted T and having opposite open ends., 55, 55 ', which connect in line to the main intake line 20, as seen in Figure 6. During normal operating conditions, the water flow will travel in the direction of the arrow 56 in the duct 54 towards the pump 24. The inverted T section of the base unit 52 further includes a vent port 60, which extends upward, from the passage 54, in fluid communication therewith, to the upper open end 62. The end upper open 62 is rolled by an annular flange 64, which has a 0-ring seal 67, mounted on the upper face 68. A brittle membrane 70 abuts the O-ring, 67, in a covering relationship to the part open upper 62 of the ventilation door 60. The fragile membrane 70 can be provided with an increased thickness, around its outer periphery, which defines a surface in contact with the ring 72. The central area 74 inside the ring 72 that surrounds it , it extends through and covers completely open upper part 62 of vent gate 60 and is of a reduced thickness relative to ring 72. Fragile membrane 70 and particularly central area 74, can be formed of glass or other material having characteristics of being torn apart or disintegrated The thickness of the central zone 74 of the fragile membrane 70 will vary depending on the desired predetermined negative pressure, in which the fragile membrane is imploded and disintegrated, as well as the diameter of the opening 62, which the central area 74 covers and the characteristics of the membrane material. However, the central area 74 is thin (in many cases less than 3,175 mm thick) and will implode and disintegrate in response to the suction force (indi- cated by arrow 76), as occurs when one or more of the obstructions are obstructed. suction admissions. The ideal vacuum pressure, in which the brittle membrane 70 disintegrates, is approximately 51 cm Hg. When the brittle membrane 70 is disintegrated, as a result of the suction force of the vacuum condition in the passage 54 and the ventilation door 60, the air from the atmosphere is able to quickly enter through the open top 72 to fill the intake lines of the fluid circulation system, thus eliminating the vacuum. The frangible membrane 70 is held in place, in deck relation to the open end 62, by an attachment 80, having a lower annular face 82, which opposes the flange 64, sandwiching the ring 72 of the fragile membrane 70. between it, as seen in Figure 7. The O-ring, 67, absorbs the pressure to prevent the brittle membrane 70 from splitting, as the accessory 80 is advanced towards the flange 64 and against the ring 72 of the fragile membrane 70. A female coupling 84 is provided to facilitate attachment of the accessory 80 to the base unit 52. by enabling the thread advance and removal of the accessory 80 relative to the flange 64 and the fragile membrane 70. The threads 85 around the The outer periphery of the accessory 80 is meshed with the corresponding threads 86 on the internal face of the female coupling 84. A flange 87, directed to the inside, at the lower open end of the female coupling 84 engages the lower flange of the flange 64 of the gate of v entilation The accessory also includes a flat edge 88 which proceeds inwardly to a reduced diameter extension 89. This fitting 80 is open at both opposite ends and has a larger diameter between the annular face 82, as compared to an upper open end 90. rim 88 in the fitting 88 is provided with a plurality of inlet holes 94, which extend from the upper rim 88, through the thickness of the accessory 80 to provide communication of the air flow between the outer atmosphere and an internal chamber 96 above of the fragile memory 70. Once the fragile membrane 70 disintegrates, air from the atmosphere enters through the holes 94 of the air inlet and through the upper opening 62 of the ventilation damper 60 and through the lines of suction intake system, to eliminate the vacuum.

An electrical switch device 100 can be mounted to the fluid vacuum safety coupling 50, as shown in Figures 7 and 8. To facilitate the attachment of the electrical switch device 100, a female coupling 102 can be mounted to the device 100 for the thread engagement with the outer threaded surface 91 over the reduced diameter extension 89 of the fitting 80. The bottom portion of the electrical switch device 100 has a sensing assembly 104, which extends through the open end 90 of the fitting 80. The sensor assembly 104 may be provided with a plunger or rod 106, which extends downwardly, so that its distal end engages the upper surface of the frangible membrane 70. An orientation element within the device 100 may be used for pushing the plunger 106 down against the frangible membrane 70. This plunger 106 serves as an indicator to the electric switch device. rich, which indicates the state of the fragile membrane 70. The disintegration of this fragile membrane 70 protrudes in a further downward extension of the plunger 106, thus activating the electrical switch device 100. This electrical switch device 100 can activate an audible alarm, housed within the device 100 and / or a remote location, by means of a wiring or a wireless connection. The electrical switch device 100 may also be used to stop the pump 24. Further, the electrical switch device 100 may be used to activate virtually any electronic component to perform a desired function, once the fragile membrane 70 has been torn apart. While the present invention has been shown and described in accordance with its preferred embodiments, which represent the best mode of the invention at the time of filing this patent application, it will be recognized that variations, modifications and changes may be made in the present description, without departing from the spirit and scope of the invention, as stated in the following claims and within the doctrine of equivalents.

Claims (15)

1. CLAIMS 1. A device for use in a fluid transfer system, having a pump, which sucks water from a reservoir, through one or more intake lines, each extending from an open end in the reservoir to a pump intake; this device comprises: a resource for detecting negative pressure levels in the fluid transfer system; a resource for analyzing the negative pressure levels detected, in relation to a predetermined interval of negative pressure levels; and a vacuum pressure relief element, operated in response to the detection of a detected pressure level, which is outside a predetermined range, to introduce positive pressure to the intake lines of the system, thus eliminating the suction in its open ends.
2. 2. A device, as claimed in claim 1, in which the vacuum pressure relief element includes a vacuum interrupter, structured and arranged to introduce air from the atmosphere to said one or more intake lines, in its actuation.
3. 3. A device, as claimed in claim 2, further including a resource for disabling the pump, to prevent its continued operation in the actuation of the vacuum pressure relief element.
4. 4. A device, as claimed in claim 3, further comprising an indicating element, to indicate detection of the detected negative pressure level, which is outside the predetermined range.
5. 5. A device, as claimed in claim 1, further comprising a control element, communicating with the detection element, said analyzer element and the vacuum pressure relief element, to initiate the actuation of said relief element of vacuum pressure.
6. 6. A device, as claimed in claim 5, wherein said control element includes a relay element, to selectively direct the flow of electric current to the vacuum pressure relief element, for its actuation, upon detecting that the pressure level negative detected is outside the predetermined range.
7. 7. A device, as claimed in claim 6, in which the relay element is further structured to direct and interrupt the flow of electric current selectively to the pump, to disable the pump by detecting that the level of negative pressure detected is outside the default interval.
8. 8. A device, as claimed in claim 7, in which the relay element is further structured to selectively direct the flow of the electric current to one or more indicating elements, to indicate that the detection of the negative pressure level detected is outside the default interval.
9. 9. A device, as claimed in claim 4, wherein the indicating element includes at least one audible alarm device.
10. 10. A device, as claimed in claim 4, wherein the indicating element includes at least one visual alarm device.
11. 11. A device for use in a fluid transfer system, having a pump, which sucks water from a reservoir, through one or more intake lines, each extending from an open end in the reservoir to an intake of the bomb; this device comprises: a resource for detecting negative pressure levels in the fluid transfer system; a resource for analyzing the negative pressure levels detected, in relation to a predetermined interval of negative pressure levels; a vacuum pressure relief element, which acts in response to the detection of a detected pressure level, outside the predetermined range, to introduce a positive pressure to the intake lines of the system, thus eliminating the suction of its open ends; and a control element, communicating with the detection element, said analyzer element and said vacuum pressure relief element, for initiating the actuation of the vacuum pressure relief element.
12. 12. A device, as claimed in claim 11, wherein said analyzer element includes a resource for selectively adjusting the predetermined range of negative pressure levels.
13. 13. A device, as claimed in claim 12, wherein said control element is structured and arranged to disable the pump, to prevent its continued operation, on detection that the detected negative pressure level is outside the predetermined range.
14. 14. A device, as claimed in claim 13, in which the control element is structured and arranged to drive one or more indicator elements, to indicate that the detection of the detected negative pressure level is outside the predetermined range, to actuate said control element. Vacuum pressure relief and disable the pump.
15. 15. A device for use in a fluid transfer system, having a pump, which sucks fluid from a reservoir, through one or more intake lines, each extending from an open end in the reservoir to an intake of the bomb; said device comprises: a resource for selecting an operational range of negative pressure levels; a resource to analyze the levels of negative pressures between the pump and the open ends of the intake lines; a vacuum pressure relief element, to introduce a negative pressure in the intake lines of the system, in order to remove the suction at the open ends of the intake lines; and a start element for actuating said vacuum pressure relief element and responsible for the detection of a negative pressure level analyzed that is outside the selected operational range.