Pump unit and auxiliary pressure pump unit

Abstract

To provide a pump unit that can prevent waterdrop, and to provide an auxiliary pressure pump unit.SOLUTION: A pump unit 111 includes: a pump part 122 including a plurality of pump casings 141, a discharge casing 145 installed to the pump casing 141 of the uppermost stage, and a shaft seal member 146 installed to the discharge casing 145; and a water tank 126 for fixing the pump part 122 while the shaft seal member 146 is positioned lower than a stop water level.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a pump unit and an auxiliary pressurizing pump unit in which a pump section is immersed in a liquid. [Background technology]

[0002] Pump units that supply liquid to a secondary side have been known for some time. Such pump units are used for a variety of purposes, including a known technique for using a pump unit as a fire pump in an automatic fire extinguishing system.

[0003] Fire pumps used in automatic fire extinguishing systems supply water to sprinklers and other devices in the event of a fire. For example, automatic fire extinguishing systems activate the fire pump when pressure in the piping drops. In automatic fire extinguishing systems where the activation of the fire pump and the activation of a fire alarm are linked, false activation of the fire alarm can be a problem if the fire pump malfunctions due to a change in saturated vapor pressure in the piping or a pressure drop caused by a water leak. Therefore, a known configuration of automatic fire extinguishing systems is one in which an auxiliary booster pump unit is connected to the secondary side of the fire pump to prevent a pressure drop in the piping and prevent the fire pump from malfunctioning.

[0004] Due to the operating characteristics of the automatic fire extinguishing equipment as described above, the auxiliary booster pump unit has very low start-up frequency and start-up time. Such auxiliary booster pump units generally employ plunger pumps (see, for example, Patent Document 1), submersible pumps (see, for example, Patent Document 2), land-based multi-stage pumps, etc.

[0005] In particular, submersible pumps are quieter and require a smaller installation area than other pumps because the pump unit is integrated into the water tank. These submersible pumps are particularly used in the field of machine tools. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5457229 [Patent Document 2] Patent No. 4094736 Summary of the Invention [Problem to be solved by the invention]

[0007] For example, when used in an automatic fire extinguishing system, a submersible pump unit must be provided with a check valve on the secondary side of the pump unit to maintain pressure in the secondary piping of the fire pump. Furthermore, a submersible pump unit must have an outlet space above the water tank. Therefore, the shaft seal of the pump unit and the upper part of the multi-stage casing are located in the outlet space. However, there is a risk that the pump unit may draw air through the shaft seal and the casing, which are exposed to the air. And if air is drawn through the shaft seal and the casing, which are exposed to the air, there is a risk that the pump unit may fall into the water.

[0008] When water falls, air enters the pump, and when the auxiliary pressure pump unit is operated after water falls, air is sent into the piping. If the amount of air in the piping increases, air entrapment occurs, which may cause the performance of the automatic fire extinguishing equipment to become unstable.

[0009] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a pump unit and an auxiliary pressure pump unit that can prevent water from falling into the pump unit. [Means for solving the problem]

[0010] According to one aspect of the present invention, the pump unit comprises a plurality of pump casings, a discharge casing provided in the uppermost pump casing, a pump section having a shaft sealing member provided in the discharge casing, and a water tank in which the shaft sealing member is positioned below the stopping water level and which secures the pump section. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a pump unit and an auxiliary pressure pump unit that can prevent falling into water. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is an explanatory diagram showing the configuration of a fire extinguishing system according to an embodiment of the present invention; [Figure 2] FIG. 2 is a perspective view showing the configuration of an auxiliary pressure pump unit used in the fire extinguishing system. [Figure 3] FIG. 3 is a cross-sectional view showing the configuration of the auxiliary pressure pump unit. DETAILED DESCRIPTION OF THE INVENTION

[0013] The configuration of a pump unit 111 according to one embodiment of the present invention will be described below with reference to Figures 1 to 3. In this embodiment, the pump unit 111 will be described as an auxiliary pressurizing pump unit used as a water supply facility in a fire extinguishing facility 100. For this reason, the pump unit 111 will be described below as an auxiliary pressurizing pump unit 111.

[0014] FIG. 1 is an explanatory diagram showing the configuration of a fire extinguishing system 100 according to one embodiment of the present invention, FIG. 2 is a perspective view showing the configuration of an auxiliary pressure pump unit 111, and FIG. 3 is a cross-sectional view showing the configuration of the auxiliary pressure pump unit 111.

[0015] 1, the auxiliary pressure pump unit 111 is used in a fire extinguishing system 100 installed in a building. The auxiliary pressure pump unit 111 is used to increase the pressure in the piping 6 when the pressure in the piping 6 of the fire extinguishing system 100 falls below a predetermined pressure.

[0016] First, the configuration of the fire extinguishing system 100 will be described. As shown in Fig. 1, the fire extinguishing system 100 includes a fire pump system 1, an auxiliary pressurizing device 2, a water discharge means 3, a fire detection device 4 including a fire alarm and the like, a water supply source 5, and piping 6 that fluidly connects the components of the fire extinguishing system 100. The fire extinguishing system 100 is an automatic fire extinguishing system that detects a fire based on the pressure in the fire detection device 4 and the piping 6, and discharges water from the water discharge means 3.

[0017] The fire pump system 1 includes, for example, a pump unit 12, a discharge pipe 13, a pressure tank 14, and a control panel 18.

[0018] The pump unit 12 includes a pump 21 and a motor 22. The pump 21 has a suction port and a discharge port. The pump 21 houses an impeller fixed to a rotating shaft therein. The pump 21 discharges pressurized water to the secondary side.

[0019] The motor 22 is configured to be able to rotate a rotary shaft. The motor 22 rotates the rotary shaft to drive the impeller of the pump 21. The motor 22 is connected to the control panel 18.

[0020] One end of the discharge pipe 13 is connected to the discharge port of the pump 21, and the other end is connected to the piping 6. The discharge pipe 13 has a check valve 13a.

[0021] The pressure tank 14 is configured to be able to store water at a predetermined pressure discharged from the pump 21. The pressure tank 14 is provided, for example, in the discharge pipe 13. The pressure tank 14 includes, for example, a pressure gauge and a pressure detector 33. The pressure gauge detects the pressure inside the pressure tank 14. The pressure detector 33 is connected to the control panel 18 via a signal line. The pressure detector 33 transmits the pressure value inside the pressure tank 14 to the control panel 18. The pressure detector 33 may be configured to be provided in the discharge pipe 13 so as to be able to detect the pressure inside the discharge pipe 13, or may be configured to be provided in the piping 6 other than the discharge pipe 13.

[0022] The control panel 18 includes a control unit therein. The control panel 18 also includes an input device, a memory unit, a notification unit, a communication unit, and a terminal unit. The control panel 18 also includes, for example, a control board and a housing.

[0023] The control board is configured, for example, by mounting a control unit, a memory unit, a communication unit, and a terminal unit on a single board. The housing accommodates the control board inside and has an input device and a notification unit located on part of its outer surface. The housing also accommodates devices such as a power transformer, a current transformer for current measurement, an electromagnetic contactor, and a molded case circuit breaker inside.

[0024] The control unit is a processor and is connected to the pressure detector 33 via a signal line. The control unit is, for example, a processing circuit such as a microcomputer or CPU, but is not limited to these, and can be set appropriately as long as it can control the motor 22 based on control data such as a control program and parameters stored in the storage unit. The control unit is electrically connected to the input device, storage unit, notification unit, and communication unit via signal lines such as a bus line.

[0025] The control unit is configured to be able to drive the motor 22. When the control unit determines that a fire has occurred, the control unit is configured to be able to drive the motor 22. As a specific example, when the control unit receives a start signal for the pump unit 12 issued by the fire detection device 4, the control unit drives the motor 22 in accordance with the program stored in the storage unit.

[0026] The input device is configured to allow input of information such as date and time, commands, etc. The input device transmits the input information to the control unit.

[0027] The storage unit includes so-called memory and storage. The storage unit determines whether a fire has occurred and, when a fire has been determined, stores a program for driving the motor 22, a program for performing an inspection operation, which is a specific operation, and various parameters for executing these programs, such as pressure, time, and frequency for driving the motor 22.

[0028] The storage unit may store, for example, any of the programs or parameters as non-rewritable. In such an example, the storage unit may set a specific parameter to be non-rewritable after it is stored by the manufacturer of the fire pump system 1, and set other parameters to be rewritable with values ​​input by the input device.

[0029] The storage unit functions as a counter memory for the counter function of the control unit. The storage unit also stores, for example, the starting pressure for starting the pump unit 12, the shut-off head during shut-off operation, and a control program for the pump unit 12 in the event of a fire and during each inspection operation.

[0030] The notification unit is configured to be able to notify the outside of an abnormality based on information transmitted from the control unit when an abnormality occurs in the pump unit 12. The notification unit includes, for example, a display unit that displays information, a lamp that displays information by lighting up or flashing, and an audio unit that notifies the outside of information by sound and a display that displays information.

[0031] The communication unit is configured to be able to send and receive information to and from the outside. For example, the communication unit outputs information sent from the control unit to the outside wirelessly or via a wired connection. For example, the communication unit transmits information to an external terminal. In other words, the control unit transmits information to a management center or an external terminal via the communication unit via a network such as the Internet or a LAN, wireless communication technology, or a wired cable.

[0032] The auxiliary pressurizing device 2 is a device that automatically operates when the pressure in the piping 6 connected to the water discharge means 3 drops, and restores the pressure in the piping 6 before the fire pump device 1 starts.

[0033] As shown in Figures 1 to 3, the auxiliary pressurizing device 2 includes, for example, an auxiliary pressurizing pump unit 111, a pressure tank 112 provided on the secondary side of the auxiliary pressurizing pump unit 111, a pressure detector 113 connected to the pressure tank 112, and a control panel 115 which is a control device.

[0034] The auxiliary pressurizing pump unit 111 includes an auxiliary motor (motor section) 121, an auxiliary pump (pump section) 122 driven by the auxiliary motor 121, a joint 123 connecting the auxiliary motor 121 and the auxiliary pump 122, a connecting pipe 124 connected to the auxiliary pump 122, a check valve 125 connected to the connecting pipe 124, and a water tank 126 in which the auxiliary pump 122 is placed. The auxiliary pressurizing pump unit 111 is a submerged pump unit in which a portion of the auxiliary pump 122 is submerged in water in the water tank 126.

[0035] The auxiliary motor 121 is electrically connected to the control panel 115. The auxiliary motor 121 is disposed on a water tank 126. The auxiliary motor 121 is fixed to the water tank 126 directly or indirectly via an auxiliary pump 122. The auxiliary motor 121 includes a motor casing 121a, a stator 121b provided in the motor casing 121a, a rotor 121c rotated by the stator 121b, a motor shaft 121d fixed to the rotor 121c, and a bearing member 121e that supports the motor shaft 121d. The auxiliary motor 121 also includes a cooling fan 121f.

[0036] The backing pump 122 has, for example, a primary side, which is the suction side, disposed at the bottom of the water tank 126, and a secondary side, which is the discharge side, connected to the connecting pipe 124. The backing pump 122 is a multi-stage pump. The backing pump 122 includes a plurality of pump casings 141, a plurality of impellers 142 housed in each pump casing 141, a rotating shaft 143 to which each impeller 142 is fixed, a suction casing 144 connected to the lowest stage of the plurality of pump casings 141, a discharge casing 145 connected to the highest stage of the plurality of pump casings 141, and a shaft seal member 146 provided on the discharge casing 145.

[0037] The multiple pump casings 141 are stacked in the direction of gravity, in other words, perpendicular to the water surface. The multiple impellers 142 rotate within each pump casing 141 in accordance with the rotation of the rotary shaft 143, sucking in water, increasing its pressure, and discharging the water to the secondary side.

[0038] The rotary shaft 143 is connected to the motor shaft 121d via a joint 123. The suction casing 144 is connected to the lowermost pump casing 141. The suction casing 144 has, for example, a strainer.

[0039] Discharge casing 145 is connected to the uppermost pump casing 141. Discharge casing 145 is formed to extend in one direction, with one end connected to pump casing 141 and the other end connected to auxiliary motor 121. Discharge casing 145 has, for example, a flange portion 145a at its midpoint that is fixed to water tub 126, and is fixed to water tub 126 via flange portion 145a with fastening members 145b such as bolts.

[0040] Discharge casing 145 has a shaft seal member 146 fixed to one end thereof, which is fixed to pump casing 141. Discharge casing 145 extends from one end to the other end, extending from inside water tank 126 to the outside of water tank 126, and has a discharge portion 145c at the other end having a discharge port that opens outside water tank 126. The height position of one end of such discharge casing 145 is determined so that, when fixed to water tank 126, shaft seal member 146 attached to one end is located below the stationary water level of water tank 126. In other words, when discharge casing 145 is attached to water tank 126, one end including the portion where shaft seal member 146 is attached is located below the stationary water level of water tank 126.

[0041] The shaft seal member 146 is, for example, a mechanical seal, and provides a seal between the rotary shaft 143 and the discharge casing 145.

[0042] The joint 123 is disposed, for example, above the flange portion 145a of the discharge casing 145, and connects the motor shaft 121d and the rotary shaft 143 together.

[0043] The connecting pipe 124 is connected to the piping 6. More specifically, the connecting pipe 124 constitutes a part of the piping 6.

[0044] The check valve 125 is provided in the connecting pipe 124. The check valve 125 regulates the movement of water from the secondary side of the auxiliary pump 122 to the auxiliary pump 122.

[0045] Water tank 126 is a water source for auxiliary pressure pump unit 111. Water tank 126 includes water tank body 151, water supply port 152 provided in water tank body 151, ball tap 153 provided in water supply port 152, overflow pipe 154 provided in water tank body 151, water level detection sensor 155, and drain port 156.

[0046] Water-tank main body 151 is configured, for example, in the shape of a rectangular box. Water-tank main body 151 has a capacity capable of storing a predetermined amount of water inside. The top plate of water-tank main body 151 is formed so that discharge casing 145 can be fixed via flange portion 145a. Water-tank main body 151 also has openings appropriately formed therein through which fastening members can be inserted to fix discharge casing 145, water level detection sensor 155, and various components. When flange portion 145a of discharge casing 145 is fixed, water-tank main body 151 fixes auxiliary pump (pump section) 122 with shaft seal member 146 positioned below the stop water level.

[0047] Water supply port 152 is provided in aquarium body 151 and supplies water into aquarium body 151. Water supply port 152 is formed, for example, by a vent pipe that extends in a direction perpendicular to the direction of gravity in aquarium body 151 and has a portion disposed inside aquarium body 151 that is bent 90 degrees and extends downward along the direction of gravity.

[0048] Ball tap 153 includes shaft 153a, ball 153b attached to the tip of shaft 153a, and on-off valve 153c that opens and closes water supply port 152 by displacement of ball 153b. Ball tap 153 has ball 153b floating on the water surface that moves up and down, and on-off valve 153c opens to open water supply port 152 until the water level in water-tank body 151 reaches the stop water level, and when the water level in water-tank body 151 reaches the stop water level, on-off valve 153c closes to block water supply port 152. In other words, after auxiliary pump (pump section) 122 is stopped, ball tap 153 supplies water to water-tank body 151 until the water level in water-tank body 151 stabilizes at the stop water level.

[0049] Overflow pipe 154 is provided in water tank body 151. Overflow pipe 154 extends, for example, in a direction perpendicular to the direction of gravity in water tank body 151. Overflow pipe 154 is provided below water supply port 152 and above the stopped water level. Also, for example, overflow pipe 154 is positioned offset from water supply port 152 in the depth direction of water tank body 151.

[0050] Water level detection sensor 155 detects the water level in water tank main body 151. Water level detection sensor 155 outputs information about the detected water level as a signal to control panel 115. For example, water level detection sensor 155 has multiple electrodes so that it can detect different water levels.

[0051] Drain port 156 is provided on the lower end side of water tank body 151. Drain port 156 has a manual on-off valve 156a and is formed to be openable and closable.

[0052] The pressure tank 112 is provided in the connecting pipe 124. The pressure tank 112 is an accumulator.

[0053] The pressure detector 113 is connected to the control panel 115 via a signal line. The pressure detector 113 is provided on the connecting pipe 124 so as to be able to detect the pressure inside the connecting pipe 124. Note that the pressure detector 113 may also be configured to be provided on a pipe 6 other than the connecting pipe 124.

[0054] The starting pressure of the backing pump 122 is set higher than the starting pressure of the pump unit 12 of the fire pump system 1. The stopping pressure of the backing pump 122 is set lower than the shutoff pressure of the fire pump system 1.

[0055] For example, if the pressure detected by the pressure detector 113 is determined to be equal to or lower than the start pressure, the auxiliary pump 122 starts. Also, if the pressure detected by the pressure detector 113 is determined to be equal to or higher than the stop pressure while the auxiliary pump 122 is operating, the auxiliary pump 122 stops.

[0056] The sprinkler 211 includes an installation pipe 211a that branches off from and is connected to the piping 6 and is installed on each floor, and a plurality of sprinkler heads 211b that are installed on the installation pipe 211a and are installed on each floor. The sprinkler 211 may also include a detector that can detect the amount of water (flow rate) and pressure between the installation pipe 211a and the sprinkler head 211b.

[0057] The sprinkler heads 211b have water outlets that can open and spray water onto the floors of a building when exposed to heat during a fire, for example. The sprinkler heads 211b are also configured so that, for example, when one of the sprinkler heads 211b installed on the same floor opens and sprays water, the other sprinkler heads 211b installed on the same floor also open and spray water in unison.

[0058] When water flows through the pipe 6 at a predetermined flow rate or velocity, the flow detector 314 activates a switch provided therein and issues a start signal for the pump unit 12 to the control panel 18 .

[0059] The water supply source 5 is a water tank for fire extinguishing. The water supply source 5 is provided on the primary side of the fire pump device 1.

[0060] The piping 6 is provided on the secondary side of the fire pump system 1 and connected to the sprinkler 211. The piping 6 is provided with a water flow detector 314. The piping 6 is closed by the sprinkler 211 at an end or midway.

[0061] According to the auxiliary booster pump unit 111 used in the fire extinguishing equipment 100 configured in this manner, when the pressure detected by the pressure detector 113 as the pressure on the secondary side of the discharge casing 145 falls below the startup pressure, the control panel 115 can start the auxiliary pump 122 to increase the pressure in the piping 6. As a result, the fire extinguishing equipment 100 can prevent the pressure in the piping 6 from decreasing to the pressure at which the fire pump system 1 operates, except when a fire has occurred, and can prevent the fire pump system 1 from malfunctioning.

[0062] Furthermore, auxiliary pressure pump unit 111 is an immersed pump, and discharge casing 145 and shaft seal member 146 of auxiliary pump 122 are disposed below the stop water level of water tank main body 151. Therefore, when auxiliary pressure pump unit 111 is stopped, pump casing 141 of auxiliary pump 122, one end side of discharge casing 145 where shaft seal member 146 is provided, and shaft seal member 146 are immersed in the water of water tank main body 151.

[0063] Therefore, even if the auxiliary pressure pump unit 111 is stopped for a long period of time, air is not drawn into the auxiliary pump 122 from the shaft seal member 146 or between the casings 141 and 145, so that water can be prevented from falling.

[0064] Therefore, when the auxiliary pressure pump unit 111 is started, air can be prevented from being sent into the pipe 6.

[0065] As described above, the auxiliary pressure pump unit 111 according to one embodiment is an immersion pump, and the shaft seal member 146 is disposed below the stop water level, thereby preventing air from entering the discharge casing 145. The present invention is not limited to the above-described embodiment. For example, in the above example, auxiliary pressure pump unit 111 used in fire extinguishing equipment 100 has been described as an example of pump unit 111, but the present invention is not limited to this. That is, pump unit 111 can be used for purposes other than fire extinguishing equipment 100 as long as it is configured so that pump casing 141 of auxiliary pump (pump section) 122, one end side of discharge casing 145, and shaft seal member 146 are located at a position lower than the stopping water level of water tank main body 151. For example, pump unit 111 may be configured to be used for machine tools, or may be configured to be used for other purposes.

[0066] That is, the present invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the embodiments may be implemented in appropriate combinations, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combining selected elements from the disclosed elements. For example, if the problem can be solved and the desired effect can be obtained even if some elements are deleted from all elements shown in the embodiments, the configuration from which these elements are deleted can be extracted as an invention. [Explanation of symbols]

[0067] 100...fire extinguishing equipment, 1...fire pump device, 2...auxiliary pressure device, 3...water discharge means, 4...fire detection device, 5...water supply source, 6...piping, 12...pump unit, 13...discharge pipe (piping), 13a...check valve, 14...pressure tank, 18...control panel, 21...pump, 22...motor, 33...pressure detector, 111...auxiliary pressure pump unit (pump unit), 112...pressure tank, 113...pressure detector, 115...control panel, 121...auxiliary motor (motor section), 121a...motor casing, 121b...stator, 121c...rotor, 121d...motor shaft, 121e...bearing member, 121f...fan, 122...auxiliary pump (pump section), 123...Joint, 124...Connecting pipe, 125...Check valve, 126...Water tank, 141...Pump casing, 142...Impeller, 143...Rotating shaft, 144...Suction casing, 145...Discharge casing, 145a...Flange portion, 145b...Fastening member, 145c...Discharge portion, 146...Shaft sealing member, 151...Water tank body, 152...Water supply port, 153...Ball tap, 153a...Shaft, 153b...Ball, 153c...Opening / closing valve, 154...Overflow pipe, 155...Water level detection sensor, 156...Drain outlet, 156a...Manual opening / closing valve, 211...Sprinkler, 211a...Installation pipe, 211b...Sprinkler head, 314...Flow detector.

Claims

1. a pump section including a plurality of pump casings, a discharge casing provided in the uppermost pump casing, and a shaft seal member provided in the discharge casing; a water tank into which water is further supplied after the pump unit is stopped until the water level becomes stable at a stop water level, and the shaft seal member is positioned below the stop water level to fix the pump unit; A pump unit comprising:

2. The pump unit according to claim 1 , wherein the shaft seal member is disposed below a water outlet space of the water tank.

3. The pump portion has a rotating shaft, a motor section connected to the pump section and having a motor shaft; The pump unit according to claim 1 , further comprising: a joint that connects the rotating shaft and the motor unit.

4. The pump unit according to claim 1 , further comprising a check valve provided on a secondary side of the discharge casing.

5. A pump unit according to any one of claims 1 to 4, a control device that drives the pump unit when the pressure on the secondary side of the discharge casing becomes equal to or lower than a predetermined pressure; An auxiliary pressure pump unit comprising:

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