PUMP SYSTEM, REFRIGERANT CIRCULATION DEVICE, AND CONTROL DEVICE

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2024-056148, filed on Mar. 29, 2024, the entire contents of which are hereby incorporated herein by reference.

1. FIELD OF THE INVENTION

The present disclosure relates to pump systems, refrigerant circulation devices, and control devices.

2. BACKGROUND

In a refrigerant circulation device (hereinafter, also referred to as “CDU”) according to the related art, a plurality of pumps are connected in parallel to a refrigerant flow path. Each of the plurality of pumps is insertable into and removable from the housing of the CDU. With this configuration, in the CDU, another pump can be inserted into and removed from the housing in a state where a portion of the pumps is operated (that is, a state in which the refrigerant is circulated).

However, in the CDU of the background art, since a plurality of pumps are connected in parallel to the flow path, there is a risk that the refrigerant flows back. Specifically, when a pump is attached to the housing in a state where the refrigerant is circulated in the CDU, the refrigerant circulating in the housing may flow into the attached pump in a reverse flow.

SUMMARY

A pump system according to a first example embodiment of the present disclosure includes a housing, a plurality of pumps, and a controller. The housing includes an opening and a fluid flow path. The plurality of pumps are insertable into and removable from the housing via the opening, and are connected to the flow path by being attached to the housing. When the controller recognizes that a second pump other than a first pump among the plurality of pumps is connected to the flow path while the first pump of the plurality of pumps is in operation, the controller is configured or programmed to stop operation of the first pump only for a specific time. The controller is configured or programmed to control power supply to the second pump during the specific time.

A refrigerant circulation device according to a second example embodiment of the present disclosure includes the pump system. The fluid is a refrigerant.

A control device according to a third example embodiment of the present disclosure can control a plurality of pumps. The plurality of pumps are insertable into and removable from a housing via an opening, and are connected to a flow path by being attached to the housing. The control device includes a stop controller and a power supply controller. When the stop controller recognizes that a second pump other than a first pump among the plurality of pumps is connected to the flow path while the first pump of the plurality of pumps is in operation, the stop controller is configured or programmed to stop operation of the first pump only for a specific time. The power supply controller is configured or programmed to control power supply to the second pump during the specific time.

The above and other elements, features, steps, characteristics and advantages of the present disclosure will become more apparent from the following detailed description of the example embodiments with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating a configuration of a cooling system 100 according to an example embodiment of the present disclosure.

FIG. 2 is a block diagram of a CDU 1 and a pump system 13 according to a first example embodiment of the present disclosure.

FIG. 3 is a perspective view illustrating pumps 19a and 19b to be inserted into and removed from a housing 11 according to an example embodiment of the present disclosure.

FIG. 4 is a timing chart illustrating operations of the CDU 1 and the pump system 13 illustrated in FIG. 2.

FIG. 5 is a flowchart illustrating operations of the CDU 1 and the pump system 13 illustrated in FIG. 2.

FIG. 6 is a diagram illustrating problems and effects of the CDU 1 and the pump system 13 illustrated in FIG. 2.

FIG. 7 is a block diagram of a CDU 1 and a pump system 13 according to a second example embodiment of the present disclosure.

FIG. 8 is a diagram illustrating main portions of the CDU 1 and the pump system 13 according to the second example embodiment.

FIG. 9 is a perspective view illustrating a periphery of a power supply 16 illustrated in FIG. 7.

FIG. 10 is a diagram illustrating a modification of main portions of the CDU 1 and the pump system 13 according to the second example embodiment.

DETAILED DESCRIPTION

Hereinafter, example embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numeral and description thereof will not be repeated.

As shown in FIG. 1, a cooling system 100 includes, as elements, a refrigerant circulation device (hereinafter, also referred to as “CDU”) 1, a distribution manifold 2, a collection manifold 3, at least one cold plate 4, a cooling device 6, and flow paths 7 and 8. These elements cool at least one heat source 5 installed in a space A01.

When the cooling system 100 includes one cold plate 4, the cooling system 100 may not include the distribution manifold 2 and the collection manifold 3.

Among the elements, the CDU 1, the distribution manifold 2, the collection manifold 3, and a plurality of the cold plates 4 are installed in the space A01. The space A01 is, for example, a server room.

The space A01 is provided with a rack 9. A plurality of the heat sources 5 are accommodated in the rack 9. Each heat source 5 is typically an electronic component or electronic equipment. The electronic component is a component constituting electronic equipment, and includes, for example, a central processing unit (so-called CPU), an electrolytic capacitor, a power semiconductor module, or a printed circuit board. The electronic component operates by power supply and generates heat. The electronic equipment is a rack mounted server or a blade server. The electronic equipment may also be a projector, a personal computer, or a display.

The CDU 1 is commercially available as an element of the cooling system 100. In the case of circulation as the cooling system 100, the cooling device 6 and the flow paths 7 and 8 may be excluded from the cooling system 100. The CDU 1 may be circulated on the market alone. In a first example embodiment, the CDU 1 is accommodated, for example, in the rack 9 when in use. However, the present disclosure is not limited to this, and the CDU 1 may be installed outside the rack 9 when in use.

The CDU 1 includes a housing 11. The housing 11 includes an exterior body and a frame, and partitions the internal space of the CDU 1 from the external space of the CDU 1 by the exterior body. The housing 11 has a primary inflow port 11a, a primary outflow port 11b, a secondary inflow port 11c, and a secondary outflow port 11d in the exterior body.

A low-temperature primary refrigerant C1 flows into the primary inflow port 11a through the flow path 7. A high-temperature secondary refrigerant C2 flows into the secondary inflow port 11c from the collection manifold 3. The CDU 1 performs heat exchange by the heat exchanger 12 (see FIG. 2) between the primary refrigerant C1 (low temperature) flowing into the CDU 1 from the primary inflow port 11a and the secondary refrigerant C2 (high temperature) flowing into the CDU 1 from the secondary inflow port 11c. As a result, in the CDU 1, the thermal energy of the primary refrigerant C1 moves to the secondary refrigerant C2. Specifically, the temperature of the secondary refrigerant C2 decreases when flowing out of the CDU 1 as compared with when flowing into the CDU 1. The CDU 1 pumps the secondary refrigerant C2 having a low temperature from the secondary outflow port 11d toward the distribution manifold 2 by the pump system 13 (see FIG. 2). The CDU 1 sends the primary refrigerant C1 having a high temperature from the primary outflow port 11b to the flow path 8.

The primary refrigerant C1 is, for example, a fluid such as a coolant. Examples of the coolant include antifreeze liquid and pure water. A typical example of antifreeze liquid is an ethylene glycol aqueous solution or a propylene glycol aqueous solution. The secondary refrigerant C2 is a fluid of the same type as or a different type from the primary refrigerant C1. At least one of the primary refrigerant C1 and the secondary refrigerant C2 may be a gas refrigerant. The secondary refrigerant C2 is an example of “fluid” or “refrigerant” in the present disclosure.

In FIG. 1, the distribution manifold 2 has a common flow path 21 and a plurality of individual flow paths 22. In FIG. 1, only two individual flow paths 22 are illustrated for convenience of description. Fluids can flow through the common flow path 21 and the individual flow paths 22. One end T21 of the common flow path 21 is connected to the secondary outflow port 11d, and is used as an inflow port for a fluid in the distribution manifold 2. One end T22a of each individual flow path 22 is connected to the common flow path 21. The other ends T22b of the individual flow paths 22 are used as outflow ports for the secondary refrigerant C2 in the distribution manifold 2, and are individually connected to an inflow port 41 of the cold plate 4. Therefore, the secondary refrigerant C2 (low temperature) flowing into the inflow port (that is, the one end T21) of the distribution manifold 2 first flows in the common flow path 21, is divided into the individual flow paths 22, and then flows out from the respective outflow ports (that is, the other ends T22b) of the distribution manifold 2.

In each example embodiment, the term “connection” means “connection through which a fluid can flow” unless there is additional wording describing “connection”.

In FIG. 1, each cold plate 4 is in thermal contact with at least one heat source 5. The secondary refrigerant C2 (low temperature) flows inside each cold plate 4. In detail, each cold plate 4 is arranged in direct thermal contact with the heat source 5. Each cold plate 4 may be arranged in thermal contact with the heat source 5 via a thermally conductive sheet (not shown), for example. That is, the term “thermal contact” includes the meaning of “direct thermal contact” and the meaning of “indirect thermal contact”.

Each cold plate 4 has the inflow port 41, an outflow port 42, and an internal flow path 43 for the secondary refrigerant C2. The internal flow path 43 connects the inflow port 41 and the outflow port 42. The secondary refrigerant C2 (low temperature) flows into the inflow port 41 from the individual flow path 22 connected to the inflow port 41. The secondary refrigerant C2 flows through the internal flow path 43 to the outflow port 42. Therefore, the heat energy generated at the heat source 5 moves to the secondary refrigerant C2 flowing through the internal flow path 43 of the cold plate 4 in thermal contact with the heat source 5. As a result, the heat source 5 is cooled, and the temperature of the secondary refrigerant C2 rises. The secondary refrigerant C2 (high temperature) flows out of the outflow port 42 to the individual flow path 31 of the collection manifold 3.

In FIG. 1, the collection manifold 3 includes a plurality of the individual flow paths 31 and the common flow path 32. In FIG. 1, two individual flow paths 31 are illustrated for convenience of description. A fluid can flow through each of the individual flow paths 31 and the common flow path 32. One end T31a of each individual flow path 31 is individually connected to the outflow port 42 as an inflow port for the fluid in the collection manifold 3. The other end T31b of each of the individual flow paths 31 is connected to the common flow path 32. One end T32 of the common flow path 32 is used as an outflow port of the fluid in the collection manifold 3, and is connected to the secondary inflow port 11c. Therefore, the secondary refrigerant C2 flowing from the cold plate 4 into each inflow port (that is, the one end T31a) in the collection manifold 3 merges at the common flow path 32, and flows out from one end (that is, the one end T32) of the collection manifold to the secondary inflow port 11c of the CDU 1. Therefore, the secondary refrigerant C2 circulates through the CDU 1, the distribution manifold 2, the cold plate 4, and the collection manifold 3 in this order.

In FIG. 1, the cooling device 6 is installed outside the space A01, for example. The cooling device 6 may be installed either indoors or outdoors. The cooling device 6 is, for example, a chiller or a cooling tower. The cooling device 6 includes an inflow port 61, an outflow port 62, and an internal flow path 63 for the primary refrigerant C1, a cooling unit 64, and a pump 65. The internal flow path 63 connects the inflow port 61 and the outflow port 62. Each of the cooling unit 64 and the pump 65 is inserted on the internal flow path 63.

The primary refrigerant C1 flowing into the inflow port 61 flows into the cooling unit 64 through the flow path. The cooling unit 64 cools the primary refrigerant C1 flowing into the cooling unit 64. The cooling system in the cooling unit 64 may be either an air cooling system or a water cooling system. The primary refrigerant C1 flowing out of the cooling unit 64 flows into the pump 65 through the internal flow path 63. The pump 65 pumps, toward the outflow port 62, the primary refrigerant C1 flowing into the pump 65. In FIG. 1, the pump 65 is positioned between the cooling unit 64 and the outflow port 62 in the internal flow path 63. However, the present disclosure is not limited to this, and the pump 65 may be positioned between the outflow port 62 and the cooling unit 64 in the internal flow path 63.

In FIG. 2, the CDU 1 includes the heat exchanger 12 and the pump system 13 in addition to the housing 11. The housing 11 may be regarded as a constituent of the pump system 13.

The heat exchanger 12 is, for example, a plate-type heat exchanger, and is mounted on a frame or the like of the housing 11. The heat exchanger 12 includes a plurality of heat transfer plates (that is, a laminate of heat transfer plates) 12a stacked in the same direction, an inflow port 12b, an outflow port 12c, and a flow path 12d for the primary refrigerant C1, and an inflow port 12e, an outflow port 12f, and a flow path 12g of the secondary refrigerant C2. Therefore, the flow paths 12d and 12g are disposed in the housing 11.

In each example embodiment, the term “install” means “fix an object at a specific place”.

Each of the inflow ports 12b and 12e and the outflow ports 12c and 12f is located, for example, at one end of the laminate 12a. The flow path 12d is formed in the laminate 12a, and causes the primary refrigerant C1 to flow from the inflow port 12b to the outflow port 12c. The flow path 12g is formed in the laminate 12a, and causes the secondary refrigerant C2 to flow from the inflow port 12e to the outflow port 12f.

The primary refrigerant C1 flows from the inflow port 12b into the flow path 12d in the laminate 12a, and flows through the flow path 12d in the laminate 12a toward the outflow port 12c. The secondary refrigerant C2 flows into the flow path 12g in the laminate 12a from the inflow port 12e, and flows through the flow path 12g in the laminate 12a toward the outflow port 12f.

In the laminate 12a, the high-temperature secondary refrigerant C2 and the low-temperature primary refrigerant C1 physically separate from each other and flow through the flow paths 12d and 12g. Each heat transfer plate constituting the laminate 12a is made of a material having a relatively small heat transfer resistance. Therefore, in the laminate 12a, heat exchange is performed between the primary refrigerant C1 (low temperature) and the secondary refrigerant C2 (high temperature). That is, the heat exchanger 12 performs heat exchange between the primary refrigerant C1 and the secondary refrigerant C2. As a result of the heat exchange, the thermal energy of the secondary refrigerant C2 is transferred to the primary refrigerant C1. That is, the secondary refrigerant C2 has a lower temperature when flowing out of the outflow port 12f than when flowing into the inflow port 12e.

In addition to the housing 11, the pump system 13 includes a primary flow path 14, a secondary flow path 15, a power supply 16, an operation display 17, a main body controller 18, pumps 19a and 19b, and transmission paths 23 and 24. The pumps 19a and 19b are an example of a “plurality of pumps” of the present disclosure.

The primary flow path 14 is installed in the housing 11. The primary flow path 14 is a pipe for the primary refrigerant C1 in the CDU 1. The primary flow path 14 mainly includes pipes 14a and 14b, and the inflow port 12b, the flow path 12d, and the outflow port 12c described above.

The pipe 14a connects the primary inflow port 11a and the inflow port 12b. The pipe 14b connects the outflow port 12c and the primary outflow port 11b. The primary flow path 14 may include a joint or a valve in addition to the pipes 14a and 14b.

The secondary flow path 15 is provided to the housing 11 and the pumps 19a and 19b. That is, the housing 11 has the secondary flow path 15. The secondary flow path 15 is an example of a “fluid flow path” in the present disclosure. The secondary flow path 15 is a pipe for the secondary refrigerant C2 in the CDU 1. The secondary flow path 15 mainly includes pipes 15a to 15k, tee joints 15A and 15B, sockets 15C to 15F of the coupling, plugs 15G to 15J of the coupling, pump stators 15K and 15L, and the inflow port 12e, the flow path 12g, and the outflow port 12f described above.

Each of the tee joints 15A and 15B has a first connection port, a second connection port, and a third connection port. In each of the tee joints 15A, 15B, the first connection port, the second connection port, and the third connection port are connected to each other by a flow path so that fluid can flow therethrough.

In the first example embodiment, the coupling is a joint for connecting pipes. For example, the sockets 15C to 15F have the same specification. For example, the plugs 15G to 15J have the same specification. The sockets 15C to 15F are detachably connected to the plugs 15G to 15J, respectively. Each of the sockets 15C to 15F has a valve that opens when each of the plugs 15G to 15J is attached. Each valve closes when each of the plugs 15G to 15J is detached from each of the sockets 15C to 15F.

Pumps 19a and 19b can be further connected to the secondary flow path 15. In FIG. 2, two pumps 19a and 19b are illustrated. However, the number of pumps may be plural.

The pump 19a includes the plugs 15G and 15H, pipes 15d and 15e, a pump stator 15K, a pump controller 191a, and a pump rotor and a pump motor (not illustrated) as elements. The pump stator 15K has a suction port, a discharge port, and a cavity (not illustrated). In the pump 19a, the pump rotor is supported in the cavity. The pump rotor is rotatable by a driving force generated by the pump motor under the control of the pump controller 191a. When the pump rotor rotates, the fluid flows into the cavity from the suction port of the pump stator 15K, and the fluid is pressure-fed from the discharge port of the pump stator 15K.

The pump controller 191a includes electronic circuits such as a microcomputer and a memory (not illustrated). In the pump controller 191a, the microcomputer controls the operation of the pump motor according to a program stored in the memory.

The pump 19b includes plugs 151 and 15J, pipes 15h and 15i, a pump stator 15L, a pump controller 191b, and a pump rotor and a pump motor (not illustrated) as elements. The pump 19b is similar to the pump 19a in terms of elements. Therefore, detailed description of the pump 19b will be omitted.

The pipe 15a connects the secondary inflow port 11c and the inflow port 12e. The pipe 15b connects the outflow port 12f and the first connection port of the tee joint 15A. The pipe 15c connects the second connection port of the tee joint 15A and the socket 15C. The pipe 15d connects the plug 15G and the suction port of the pump stator 15K. The pipe 15e connects the discharge port of the pump stator 15K and the plug 15H. The pipe 15f connects the socket 15D and the first connection port of the tee joint 15B.

The pipe 15g connects the third connection port of the tee joint 15A and the socket 15E. The pipe 15h connects the plug 15I and the suction port of the pump stator 15L. The pipe 15i connects the discharge port of the pump stator 15L and the plug 15J. In this manner, the pumps 19a and 19b are connected to the secondary flow path 15. The pipe 15j connects the socket 15F and the second connection port of the tee joint 15B.

The pipe 15k connects the third connection port of the tee joint 15B and the secondary outflow port 11d.

The power supply 16 is installed in the housing 11, or attachable to or detachable from the housing 11. The power supply 16 includes a power supply circuit and the like. An AC voltage is supplied from an external power supply to the power supply 16. The external power supply is, for example, a commercial power supply or an uninterruptible power supply device. The power supply 16 generates two types of DC voltages, that is, a first DC voltage and a second DC voltage, from the supplied AC voltage. The first DC voltage is higher than the second DC voltage. The first DC voltage is supplied to, for example, the pumps 19a and 19b. The second DC voltage is supplied to, for example, the main body controller 18 and the pump controllers 191a and 191b.

The operation display 17 is, for example, a touch screen. The touch screen includes a touch panel and a touch sensor. The operation display 17 displays various images under the control of the main body controller 18.

The main body controller 18 is an integrated circuit including electronic circuits such as a microcomputer and a memory (not illustrated). The main body controller 18 is an example of a “control device” of the present disclosure. Each microcomputer controls elements of the CDU 1 and the pump system 13 according to a program stored in the memory.

The transmission path 23 includes cables 23a and 23b and connectors 23c and 23d as elements. The cable 23a connects an input/output terminal of the main body controller 18 and the connector 23c. The cable 23b connects an input/output terminal of the pump controller 191a and the connector 23d. The connectors 23c and 23d are detachable from each other, and electrically connect or electrically disconnect the cables 23a and 23b from each other.

The transmission path 24 includes cables 24a and 24b and connectors 24c and 24d as elements. The transmission path 24 is similar to the transmission path 23 in terms of elements. Therefore, detailed description of the transmission path 24 will be omitted.

As illustrated in FIG. 3, the housing 11 has openings 111a and 111b as an example of the “opening” of the present disclosure. In the first example embodiment, the housing 11 has a substantially rectangular parallelepiped shape. The openings 111a and 111b are formed side by side in the exterior body of the housing 11. Accommodation spaces 112a and 112b extend in the first direction D01 from the openings 111a and 111b toward the inside of the housing 11. Each of the accommodation spaces 112a and 112b has a shape capable of accommodating each of the pumps 19a and 19b.

The housing 11 has partition walls 113a and 113b that partition the accommodation spaces 112a and 112b. The partition walls 113a and 113b extend substantially parallel to the first direction D01. The partition walls 113a and 113b are provided with guide rails (not illustrated) capable of guiding the pumps 19a and 19b in the first direction D01 and the second direction D02 that is the opposite direction of the first direction D01. When viewed from the opening 111a, the sockets 15C and 15D and the connector 23c are located at the back of the accommodation space 112a in the first direction D01. When viewed from the opening 111b, the sockets 15E and 15F and the connector 24c are located at the back of the accommodation space 112b in the first direction D01.

The pumps 19a and 19b can be inserted into and removed from the housing 11 through the openings 111a and 111b. The pumps 19a and 19b are connected to the secondary flow path 15 by being attached to the housing 11.

The pumps 19a and 19b further include housings 192a and 192b. Each of the housings 192a and 192b has substantially the same rectangular parallelepiped shape. The housing 192a has the plugs 15G and 15H and the connector 23d on a surface that becomes an end in the first direction D01 when the pump 19a is inserted and removed. The housing 192b has the plugs 151 and 15J and the connector 24d on a surface that becomes an end in the first direction D01 when the pump 19b is inserted and removed. Note that, in FIG. 3, the plugs 15G and 15I are not illustrated for convenience of the viewing direction.

More specifically, when the housings 192a and 192b are attached to the housing 11, the housings are moved from the openings 111a and 111b toward the back of the accommodation spaces 112a and 112b in the first direction D01 by an external force applied from an operator. Meanwhile, the housings 192a and 192b are guided by the guide rails of the partition walls 113a and 113b. When the housing 192a reaches the deepest side in the first direction D01 in the accommodation space 112a, the plugs 15G and 15H are connected to the sockets 15C and 15D. At substantially the same time, the connectors 23c and 23d connect the cables 23a and 23b to each other. When the housing 192b reaches the deepest side in the first direction D01 in the accommodation space 112b, the plugs 151 and 15J are connected to the sockets 15E and 15F. At substantially the same time, the connectors 24c and 24d connect the cables 24a and 24b to each other. As a result, the pumps 19a and 19b can take in the secondary refrigerant C2 from the upstream side of the secondary flow path 15 and pressure-feed the secondary refrigerant C2 to the downstream side thereof.

On the other hand, the housings 192a and 192b move in the second direction D02 from the accommodation spaces 112a and 112b through the openings 111a and 111b by an external force applied by an operator at the time of removal to the housing 11, and move toward the outside of the housing 11.

Hereinafter, the operation of the pump system 13 when the pumps 19a and 19b are attached will be described with reference to FIGS. 1 to 6.

In the pump system 13, the main power supply of the CDU 1 is turned on by the operation of the operator in a state where the pumps 19a and 19b are attached to the housing 11. After the main power supply is turned on, the power supply 16 starts supplying a DC voltage to each portion of the CDU 1. Thereafter, the main body controller 18 transmits a command (hereinafter also referred to as a “start command”) for starting the operation of the pumps 19a and 19b, to each of the pump controllers 191a and 191b.

The pump controllers 191a and 191b start the operation of the pumps 19a and 19b in response to the reception of the start command to the pump controllers. Specifically, the pump controllers 191a and 191b output PWM signals Sa and Sb (see FIG. 4) subjected to pulse width modulation at a predetermined duty ratio, to the pump motors of the pumps 19a and 19b. As a result, in the pumps 19a and 19b, the pump motors generate power for rotating the pump rotor. As a result, the secondary refrigerant C2 flows into the CDU 1 from the secondary inflow port 11c, flows through the secondary flow path 15, and flows out from the secondary outflow port 11d. The primary refrigerant C1 pressure-fed from the cooling device 6 (see FIG. 1) flows into the primary inflow port 11a of the CDU 1. The primary refrigerant C1 flows through the primary flow path 14 and flows out from the primary outflow port 11b.

In the pump system 13, when the main power supply of the CDU 1 is turned off by the operation of the operator, the main body controller 18 transmits a command (hereinafter also referred to as a “stop command”) for stopping the operation of the pumps 19a and 19b to each of the pump controllers 191a and 191b.

The pump controllers 191a and 191b stop the operation of the pumps 19a and 19b in response to the reception of the stop command to the pump controllers. Specifically, the pump controllers 191a and 191b stop the output of the PWM signals Sa and Sb (see FIG. 4) to the pump motors of the pumps 19a and 19b.

Meanwhile, during operation of the CDU 1, a failure may occur in one of the plurality of pumps 19a and 19b. When recognizing the occurrence of a failure, the operator performs a predetermined operation (hereinafter also referred to as “first specifying operation”) on the operation display 17 to replace the pump in which the failure has occurred.

The main body controller 18 receives the first specifying operation by the operator via the operation display 17 (step S101 in FIG. 5). With the reception of the first specifying operation as a trigger, the main body controller 18 causes the operation display 17 to display a dialog (hereinafter also referred to as “replacement start image”) for replacing the pump in which the failure has occurred (step S101).

The display of the replacement start image requires the operator to designate a pump to be replaced. The operator designates a pump to be replaced from among the plurality of pumps 19a and 19b by the operation display 17. Hereinafter, the description will be continued assuming that the pump to be replaced is the pump 19b.

Next, the main body controller 18 receives designation of the pump 19b to be replaced through the operation display 17 (step S102). With the reception of the replacement target as a trigger, the main body controller 18 transmits a stop command to the pump controller 191b to stop the operation of the pump 19b to be replaced (step S102).

The pump controller 191b stops the transmission of the PWM signal Sb with the reception of the stop command to itself as a trigger, and stops the operation of the pump 19b (step S103, see time T01 in FIG. 4). The pump 19a is also in operation after the time T01. That is, even if a failure occurs in one of the plurality of pumps 19a and 19b, the CDU 1 does not stop operating. That is, the operation rate of the CDU 1 does not decrease.

When the operation of the pump 19b is stopped, the flow rate of the refrigerant in the secondary flow path 15 is reduced. In order to compensate for the refrigerant flow rate, the main body controller 18 preferably transmits a command for increasing the discharge amount of a pump (that is, the pump 19a) other than the pump 19b to the pump controller 191a. The pump controller 191a increases the discharge amount of the pump 19a by transmitting the PWM signal Sa having an increased duty ratio with the reception of a command to itself as a trigger.

After stopping the operation of the pump 19b, the operator removes the pump 19b from the housing 11. As a result, the plugs 15I and 15J are detached from the sockets 15E and 15F, and the connector 24d is detached from the connector 24c. The power supply from the power supply 16 to the pump 19b is also stopped (see time T02 in FIG. 4).

Thereafter, the operator inserts a new pump 19b different from the pump 19b before replacement into the accommodation space 112b from the opening 111b (see time T03 in FIG. 4). In the new pump 19b, the plugs 15I and 15J are eventually connected to the sockets 15E and 15F. At substantially the same time, in the new pump 19b, the connectors 24c and 24d are electrically connected to each other, so that the cable 24b and the cable 24a on the housing 11 side are connected to each other. In addition, the power supply 16 starts power supply to the new pump 19b.

Here, in response to connection of the plugs 15I and 15J of the new pump 19b to the sockets 15E and 15F, the valves of the sockets 15E and 15F are opened. The secondary refrigerant C2 is not flowing in the new pump 19b. Therefore, when the new pump 19b is attached to the housing 11, as illustrated in the upper portion of FIG. 6, in a state where the pump 19a is operated, the secondary refrigerant C2 is pressure-fed from the socket 15D of the secondary flow path 15 to the pipe 15f by the pump 19a. As a result, in the new pump 19b, the secondary refrigerant C2 flows backward from the socket 15F to the plug 15J. As a result, the pressure of the secondary refrigerant C2 in the secondary flow path 15 decreases, and the cooling performance of the CDU 1 decreases.

Therefore, in the first example embodiment, after executing step S102, that is, when recognizing that the new pump 19b other than the pump 19a is connected to the secondary flow path 15 during operation of the pump 19a, the main body controller 18 starts counting a waiting time Tw (see FIG. 4) that is a predetermined time (step S103). The pump 19a is an example of a “first pump” in the present disclosure, and the pump 19b is an example of a “second pump” in the present disclosure.

In step S103, the main body controller 18 recognizes that the new pump 19b is connected to the secondary flow path 15 since the connector 24d of the new pump 19b and the connector 24c on the housing 11 side are electrically connected to each other.

The waiting time Tw is determined by experiment or simulation in the development stage of the CDU 1. In general, in order to reliably insert the connector 24d and the plugs 151 and 15J of the new pump 19b into the connector 24c and the sockets 15E and 15F, an operator may push the new pump 19b into the housing 11 while swinging the new pump. As a result, the connectors 24c and 24d may be repeatedly electrically connected and electrically disconnected. In the first example embodiment, the waiting time Tw is set in order to execute step S106 and the subsequent steps in a state where the connectors 24c and 24d are electrically connected.

After the waiting time Tw (see FIG. 4) has elapsed, the main body controller 18 causes the pump controller 191a to stop the operation of the pump 19a for a specific time Ts (see FIG. 4), and controls the power supply to the new pump 19b during the specific time Ts (steps S104 to S106 in FIG. 5). In the example embodiment, the main body controller 18 stops the operation of the pump 19a after recognizing that the new pump 19b is connected to the secondary flow path 15. Therefore, as illustrated in the lower portion of FIG. 6, the flow of the secondary refrigerant C2 in the secondary flow path 15 is temporarily stopped, and as a result, it is possible to reduce backflow of the secondary refrigerant C2 from the socket 15F side into the plug 15J of the new pump 19b. As a result, a decrease in the cooling performance of the CDU 1 is suppressed.

In addition, stopping the operation of the pump 19a after the lapse of the waiting time Tw further reduces the degradation of the cooling performance in the CDU 1 as compared with the case where the waiting time Tw is not provided. This is because, in a case where the waiting time Tw is not provided, the main body controller 18 is more likely to repeat the start and stop of the specific time Ts by repeating the electrical connection and disconnection of the connectors 24c and 24d when the new pump 19b is attached to the housing 11.

The specific time Ts is determined by experiment or simulation in the development stage of the CDU 1. Specifically, in the new pump 19b, a certain period of time (hereinafter also referred to as “required time”) is required from the start of power supply until the power is stabilized. The specific time Ts is a time obtained by adding a margin to the required time.

Specifically, in step S104, with the lapse of the waiting time Tw (see FIG. 4) as a trigger, the main body controller 18 transmits a stop command for stopping the operation of the pump 19a to the pump controller 191a, and starts counting the specific time Ts (see time T04 in FIG. 4). The pump controller 191a stops the operation of the pump 19a in response to the reception of the stop command to itself.

In step S105, the main body controller 18 controls power supply to the new pump 19b. Specifically, the main body controller 18 starts power supply to the new pump 19b.

In step S106, when the power supplied to the new pump 19b is stabilized, the main body controller 18 restarts the pump 19a being stopped. As a result, the time during which the operation of the pump 19a stops can be shortened. In the example embodiment, the main body controller 18 transmits a start command to the pump controller 191a in response to the lapse of the specific time Ts (see time T05 in FIG. 4). The pump controller 191a restarts the output of the PWM signal Sa (see FIG. 4) to the pump motor of the pump 19a with the reception of the start command to itself as a trigger. As a result, the operation of the pump 19a is resumed.

Here, in the first example embodiment, in step S106, since the power supplied to the new pump 19b is considered to be stable as the specific time Ts elapses, it is not necessary to monitor the power supplied to the new pump 19b. Note that the main body controller 18 may monitor the power supplied to the new pump 19b instead of restarting the stopped pump 19a after the lapse of the specific time Ts, and restart the stopped pump 19a when the power is stabilized according to the monitoring result.

After step S106, that is, after the power supplied to the new pump 19b is stabilized, the main body controller 18 operates the new pump 19b (steps S107 to S109). Accordingly, the new pump 19b reliably operates.

Specifically, in step S107, the main body controller 18 displays an operation start image on the operation display 17. The operation start image is a dialog for allowing the operator to designate whether or not to start the operation of the new pump 19b.

By displaying the operation start image, the operator designates whether or not to start the operation of the new pump 19b by the operation through the operation display 17.

When it is designated that the operation of the pump 19b may be started by the operation of the operator through the operation display 17 (Yes in step S108), the main body controller 18 transmits a start command to the pump controller 191b (step S109, see time T06 in FIG. 4). The pump controller 191b starts the operation of the pump 19b in response to reception of the start command to itself. In the first example embodiment, since the operation of the operator is urged by the operation start image, the operator can easily recognize the timing at which the pump 19b can be operated.

Note that the main body controller 18 may operate both the pumps 19a and 19b in step S106 without executing steps S107 to S109.

As illustrated in FIG. 7, the CDU 1 of the second example embodiment is different from the CDU 1 of the first example embodiment (see FIG. 2) in that the pump system 13 further includes control valves 51A and 51B, a temperature sensor 52, and a flow rate sensor 53 as examples of “a plurality of components” of the present disclosure.

The control valves 51A and 51B are located, for example, in the middle of the pipes 15f and 15j of the secondary flow path 15. Each opening degree of the control valves 51A and 51B is controlled by the main body controller 18, whereby the flow rate of the secondary refrigerant C2 in the pipes 15f and 15j is adjusted.

The temperature sensor 52 is located, for example, in the pipe 15k of the secondary flow path 15, and outputs information indicating the temperature (hereinafter, also referred to as “temperature information”) of the secondary refrigerant C2 flowing through the pipe 15k to the main body controller 18.

The flow rate sensor 53 is located, for example, in the pipe 15k of the secondary flow path 15, and outputs information indicating the flow rate (hereinafter, also referred to as “flow rate information”) of the secondary refrigerant C2 flowing through the pipe 15k to the main body controller 18.

In addition to the temperature sensor 52 and the flow rate sensor 53, one pressure sensor may be disposed in the middle of each of the pipes 15f and 15j of the secondary flow path 15. The two pressure sensors detect the pressure of the secondary refrigerant 2C pumped by the pumps 19a and 19b located upstream thereof.

The main body controller 18 adjusts each opening degree of the control valves 51A and 51B based on, for example, at least one of the temperature information and the flow rate information.

The control valves 51A and 51B, the temperature sensor 52, and the flow rate sensor 53 operate at a direct current voltage (that is, electric power) supplied from the power supply 16. In the second example embodiment, as illustrated in FIG. 8, the pump system 13 further includes a common board 54, a plurality of individual boards 55A to 55D, and a plurality of first electric wires 56A to 56D.

A first wiring 541 for power transmission is formed on the common board 54. Specifically, a terminal block 542 and a plurality of connectors 543A to 543D are further mounted on the common board 54. An electric wire 161 extending from the power supply 16 is connected to the terminal block 542. The first wiring 541 is formed on the common board 54 by printing or the like, and electrically connects the terminal block 542 and the connectors 543A to 543D. Each of the connectors 543A to 543D may also be referred to as a board-to-board connector, and is electrically connected to any of the individual boards 55A to 55D when any of the individual boards 55A to 55D is inserted.

Each of the individual boards 55A to 55D is electrically connected to the first wiring 541. A second wiring 552 for power transmission is formed on each of the individual boards 55A to 55D. Specifically, the connectors 553 and 554 are further mounted on each of the individual boards 55A to 55D. Each connector 553 may also be referred to as a board-to-board connector, and is electrically connected to the connectors 543A to 543D by being inserted into the connectors 543A to 543D of the common board 54. In the individual boards 55A to 55D, the second wiring 552 is formed by printing or the like, and electrically connects the connector 553 and 554. Therefore, when each connector 553 is inserted into any one of the connectors 543A to 543D of the common board 54, the second wiring 552 is electrically connected to the first wiring 541.

The plurality of first electric wires 56A to 56D are electrically connected to the respective second wirings 552 and are for power transmission. The first electric wires 56A to 56D electrically connect the connector 554 in the individual boards 55A to 55D, the control valves 51A and 51B, the temperature sensor 52, and the flow rate sensor 53 (that is, the “plurality of components” of the present disclosure).

In the second example embodiment, the DC voltage of the power supply 16 is applied to a plurality of components (the control valves 51A and 51B, the temperature sensor 52, the flow rate sensor 53) via the common board 54 and the individual boards 55A to 55D. Therefore, in the housing 11, the total extension of the cord-like power line for supplying power to the plurality of components is shortened. In addition, since the total extension of the cord-like power line is shortened, it is easy to assemble a plurality of components in the CDU 1 and the pump system 13.

As illustrated in FIG. 8, the pump system 13 further includes second electric wires 555A and 555B for power transmission. The second electric wires 555A and 555B electrically connect the power supply 16 and the connectors 23c and 24c. The connectors 23c and 24c are examples of a “first connector” of the present disclosure.

The pump 19a further includes a pump board 193A as an element, in addition to the connector 23d and the cable 23b.

In the second example embodiment, the cable 23b is, for example, a flat cable in which a communication line and a power line are bundled. The connector 23d is an example of a “second connector” of the present disclosure, and the cable 23b is an example of a “pump electric wire” of the present disclosure. The connector 23d is electrically connected to the connector 23c by attaching the pump 19a to the housing 11 (see FIG. 7), thereby connecting the second electric wire 555A and the power line of the cable 23b.

The pump board 193A is installed in the pump housing 192a (see FIG. 3), and is electrically connected to the cable 23b. The pump controller 191a is mounted on the pump board 193A. The pump controller 191a receives power supply from the power supply 16 through the power line of the cable 23b. With this configuration, the pump board 193A is movable from one of the inside and the outside of the accommodation space 112a to the other through the opening 111a by insertion and removal of the pump 19a.

The pump 19b further includes a pump board 193B as an element, in addition to the connector 24d and the cable 24b. The pump 19b is similar to the pump 19a in terms of elements. Therefore, detailed description of the pump 19b will be omitted.

In the second example embodiment, the DC voltage of the power supply 16 is applied to the pump 19a via the connectors 23c and 23d, and is applied to the pump 19b via the connectors 24c and 24d. In other words, when the pumps 19a and 19b are attached to the housing 11, a DC voltage is applied to the pumps 19a and 19b. This makes it possible to provide the pump system 13 with good usability.

As described above, the power supply 16 generates a DC voltage from an AC voltage supplied from an external power supply. The power supply 16 supplies the generated DC voltage (that is, power) to the first wiring 541.

As illustrated in FIG. 9, the power supply 16 includes a casing 162 having a substantially rectangular parallelepiped shape. The casing 162 accommodates the above-described power supply circuit and the like. The common board 54 is indicated by a broken line in FIG. 9. The common board 54 is seen through for easy visual recognition of the power supply 16. The common board 54 is disposed along one surface 163 of the substantially rectangular parallelepiped casing 162 in the housing 11. Thus, the length of the electric wire 161 from the power supply 16 to the common board 54 can be shortened.

In the second example embodiment, the connector 554 in the individual boards 55A to 55D, the control valves 51A and 51B, the temperature sensor 52, and the flow rate sensor 53 are electrically connected by the first electric wires 56A to 56D. However, the present disclosure is not limited thereto, and as illustrated in FIG. 10, the individual board 55A and the control valve 51A may not be electrically connected by the first electric wire 56A, the main body controller 18 may be mounted on the individual board 55A, and the connector 553 and the main body controller 18 may be electrically connected by the second wiring 552.

In FIG. 10, the control valves 51A and 51B, the temperature sensor 52, and the flow rate sensor 53 may be electrically connected to the first wiring 541 of the common board 54 via the individual board 55A or not via the individual board 55A.

The example embodiments of the present disclosure are described above with reference to the drawings. However, the present disclosure is not limited to the above example embodiments, and can be implemented in various modes without departing from the gist of the present disclosure. Further, a plurality of elements disclosed in the above example embodiments can be appropriately modified. For example, a certain element illustrated in a certain example embodiment may be added to elements of another example embodiment, or some elements illustrated in a certain example embodiment may be removed from the example embodiment.

The drawings schematically show each element mainly in order to facilitate understanding of the present disclosure, and the thickness, length, number, interval, and the like of each element that is shown may be different from the actual ones for convenience of the drawings. The configuration of each element shown in the above example embodiments is an example and is not particularly limited, and it goes without saying that various modifications can be made without substantially departing from the effects of the present disclosure.

The present technology can also adopt the following configurations.

• • (1) A pump system including a housing including an opening and a flow path for fluid, a plurality of pumps that are insertable into and removable from the housing via the opening and are connected to the flow path by being attached to the housing, and a controller configured or programmed to stop operation of a first pump of the plurality of pumps only for a specific time when the controller recognizes that a second pump, other than the first pump among the plurality of pumps, is connected to the flow path while the first pump is in operation, and control power supply to the second pump during the specific time.
  • (2) The pump system according to (1), wherein when the controller recognizes that the second pump is connected to the flow path, the controller is configured or programmed to stop the operation of the first pump only for the specific time after a waiting time that is a predetermined time has elapsed.
  • (3) The pump system according to (1) or (2), wherein the controller is configured or programmed to restart the first pump being stopped when power supplied to the second pump is stabilized.
  • (4) The pump system according to any one of (1) to (3), wherein the controller is configured or programmed to operate the second pump after power supplied to the second pump is stabilized.
  • (5) The pump system according to any one of (1) to (4), further including an operation display configured to display a screen for allowing a user operation to designate whether or not the operation of the second pump is allowed to start after the power supplied to the second pump is stabilized, wherein the controller is configured or programmed to operate the second pump when the user operation designates that the operation of the second pump is allowed to start.
  • (6) The pump system according to any one of (1) to (5), further including a common board on which a first wiring for power transmission is provided, a plurality of individual boards electrically connected to the first wiring and on each of which a second wiring for power transmission is provided, a plurality of first electric wires for power transmission electrically connected to a plurality of the second wirings, and a plurality of components connected to the plurality of first electric wires.
  • (7) The pump system according to (6), further including a second electric wire for power transmission, and a first connector electrically connected to the second electric wire, wherein the pump includes a second connector electrically connected to the first connector when the pump is mounted on the housing, a pump electric wire that is an electric wire for power transmission and is electrically connected to the second connector, and a pump board that is a board electrically connected to the pump electric wire.
  • (8) The pump system according to (6) or (7), further including a power supply that includes a casing and supplies power to the first wiring, wherein the common board is located along a surface of the casing.
  • (9) A refrigerant circulation device including the pump system according any one of (1) to (8), wherein the fluid is a refrigerant.
  • (10) A control device capable of controlling a plurality of pumps that are insertable into and removable from a housing via an opening and are connected to a flow path for fluid provided to the housing by being attached to the housing, the control device including a stop controller configured or programmed to stop operation of a first pump of the plurality of pumps only for a specific time when the stop controller recognizes that a second pump, other than the first pump among the plurality of pumps, is connected to the flow path while the first pump is in operation; and a power supply controller configured or programmed to control power supply to the second pump during the specific time.

Example embodiments of the present disclosure are suitable for a refrigerant circulation device and the like, and has industrial applicability.

Features of the above-described example embodiments and the modifications thereof may be combined appropriately as long as no conflict arises.

While example embodiments of the present disclosure have been described above, it is to be understood that variations and modifications will be apparent to those skilled in the art without departing from the scope and spirit of the present disclosure. The scope of the present disclosure, therefore, is to be determined solely by the following claims.