Pump System, Refrigerant Circulation Device, and Control Device

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.

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

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.

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.

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, a cooling systemincludes, as elements, a refrigerant circulation device (hereinafter, also referred to as “CDU”), a distribution manifold, a collection manifold, at least one cold plate, a cooling device, and flow pathsand. These elements cool at least one heat sourceinstalled in a space A.

When the cooling systemincludes one cold plate, the cooling systemmay not include the distribution manifoldand the collection manifold.

Among the elements, the CDU, the distribution manifold, the collection manifold, and a plurality of the cold platesare installed in the space A. The space Ais, for example, a server room.

The space Ais provided with a rack. A plurality of the heat sourcesare accommodated in the rack. Each heat sourceis 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 CDUis commercially available as an element of the cooling system. In the case of circulation as the cooling system, the cooling deviceand the flow pathsandmay be excluded from the cooling system. The CDUmay be circulated on the market alone. In a first example embodiment, the CDUis accommodated, for example, in the rackwhen in use. However, the present disclosure is not limited to this, and the CDUmay be installed outside the rackwhen in use.

The CDUincludes a housing. The housingincludes an exterior body and a frame, and partitions the internal space of the CDUfrom the external space of the CDUby the exterior body. The housinghas a primary inflow port, a primary outflow port, a secondary inflow port, and a secondary outflow portin the exterior body.

A low-temperature primary refrigerant Cflows into the primary inflow portthrough the flow path. A high-temperature secondary refrigerant Cflows into the secondary inflow portfrom the collection manifold. The CDUperforms heat exchange by the heat exchanger(see) between the primary refrigerant C(low temperature) flowing into the CDUfrom the primary inflow portand the secondary refrigerant C(high temperature) flowing into the CDUfrom the secondary inflow port. As a result, in the CDU, the thermal energy of the primary refrigerant Cmoves to the secondary refrigerant C. Specifically, the temperature of the secondary refrigerant Cdecreases when flowing out of the CDUas compared with when flowing into the CDU. The CDUpumps the secondary refrigerant Chaving a low temperature from the secondary outflow porttoward the distribution manifoldby the pump system(see). The CDUsends the primary refrigerant Chaving a high temperature from the primary outflow portto the flow path.

The primary refrigerant Cis, 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 Cis a fluid of the same type as or a different type from the primary refrigerant C. At least one of the primary refrigerant Cand the secondary refrigerant Cmay be a gas refrigerant. The secondary refrigerant Cis an example of “fluid” or “refrigerant” in the present disclosure.

In, the distribution manifoldhas a common flow pathand a plurality of individual flow paths. In, only two individual flow pathsare illustrated for convenience of description. Fluids can flow through the common flow pathand the individual flow paths. One end Tof the common flow pathis connected to the secondary outflow port, and is used as an inflow port for a fluid in the distribution manifold. One end Tof each individual flow pathis connected to the common flow path. The other ends Tof the individual flow pathsare used as outflow ports for the secondary refrigerant Cin the distribution manifold, and are individually connected to an inflow portof the cold plate. Therefore, the secondary refrigerant C(low temperature) flowing into the inflow port (that is, the one end T) of the distribution manifoldfirst flows in the common flow path, is divided into the individual flow paths, and then flows out from the respective outflow ports (that is, the other ends T) of the distribution manifold.

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

In, each cold plateis in thermal contact with at least one heat source. The secondary refrigerant C(low temperature) flows inside each cold plate. In detail, each cold plateis arranged in direct thermal contact with the heat source. Each cold platemay be arranged in thermal contact with the heat sourcevia 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 platehas the inflow port, an outflow port, and an internal flow pathfor the secondary refrigerant C. The internal flow pathconnects the inflow portand the outflow port. The secondary refrigerant C(low temperature) flows into the inflow portfrom the individual flow pathconnected to the inflow port. The secondary refrigerant Cflows through the internal flow pathto the outflow port. Therefore, the heat energy generated at the heat sourcemoves to the secondary refrigerant Cflowing through the internal flow pathof the cold platein thermal contact with the heat source. As a result, the heat sourceis cooled, and the temperature of the secondary refrigerant Crises. The secondary refrigerant C(high temperature) flows out of the outflow portto the individual flow pathof the collection manifold.

In, the collection manifoldincludes a plurality of the individual flow pathsand the common flow path. In, two individual flow pathsare illustrated for convenience of description. A fluid can flow through each of the individual flow pathsand the common flow path. One end Tof each individual flow pathis individually connected to the outflow portas an inflow port for the fluid in the collection manifold. The other end Tof each of the individual flow pathsis connected to the common flow path. One end Tof the common flow pathis used as an outflow port of the fluid in the collection manifold, and is connected to the secondary inflow port. Therefore, the secondary refrigerant Cflowing from the cold plateinto each inflow port (that is, the one end T) in the collection manifoldmerges at the common flow path, and flows out from one end (that is, the one end T) of the collection manifold to the secondary inflow portof the CDU. Therefore, the secondary refrigerant Ccirculates through the CDU, the distribution manifold, the cold plate, and the collection manifoldin this order.

In, the cooling deviceis installed outside the space A, for example. The cooling devicemay be installed either indoors or outdoors. The cooling deviceis, for example, a chiller or a cooling tower. The cooling deviceincludes an inflow port, an outflow port, and an internal flow pathfor the primary refrigerant C, a cooling unit, and a pump. The internal flow pathconnects the inflow portand the outflow port. Each of the cooling unitand the pumpis inserted on the internal flow path.

The primary refrigerant Cflowing into the inflow portflows into the cooling unitthrough the flow path. The cooling unitcools the primary refrigerant Cflowing into the cooling unit. The cooling system in the cooling unitmay be either an air cooling system or a water cooling system. The primary refrigerant Cflowing out of the cooling unitflows into the pumpthrough the internal flow path. The pumppumps, toward the outflow port, the primary refrigerant Cflowing into the pump. In, the pumpis positioned between the cooling unitand the outflow portin the internal flow path. However, the present disclosure is not limited to this, and the pumpmay be positioned between the outflow portand the cooling unitin the internal flow path.

In, the CDUincludes the heat exchangerand the pump systemin addition to the housing. The housingmay be regarded as a constituent of the pump system.

The heat exchangeris, for example, a plate-type heat exchanger, and is mounted on a frame or the like of the housing. The heat exchangerincludes a plurality of heat transfer plates (that is, a laminate of heat transfer plates)stacked in the same direction, an inflow port, an outflow port, and a flow pathfor the primary refrigerant C, and an inflow port, an outflow port, and a flow pathof the secondary refrigerant C. Therefore, the flow pathsandare disposed in the housing.

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

Each of the inflow portsandand the outflow portsandis located, for example, at one end of the laminate. The flow pathis formed in the laminate, and causes the primary refrigerant Cto flow from the inflow portto the outflow port. The flow pathis formed in the laminate, and causes the secondary refrigerant Cto flow from the inflow portto the outflow port

The primary refrigerant Cflows from the inflow portinto the flow pathin the laminate, and flows through the flow pathin the laminatetoward the outflow port. The secondary refrigerant Cflows into the flow pathin the laminatefrom the inflow port, and flows through the flow pathin the laminatetoward the outflow port

In the laminate, the high-temperature secondary refrigerant Cand the low-temperature primary refrigerant Cphysically separate from each other and flow through the flow pathsand. Each heat transfer plate constituting the laminateis made of a material having a relatively small heat transfer resistance. Therefore, in the laminate, heat exchange is performed between the primary refrigerant C(low temperature) and the secondary refrigerant C(high temperature). That is, the heat exchangerperforms heat exchange between the primary refrigerant Cand the secondary refrigerant C. As a result of the heat exchange, the thermal energy of the secondary refrigerant Cis transferred to the primary refrigerant C. That is, the secondary refrigerant Chas a lower temperature when flowing out of the outflow portthan when flowing into the inflow port

In addition to the housing, the pump systemincludes a primary flow path, a secondary flow path, a power supply, an operation display, a main body controller, pumpsand, and transmission pathsand. The pumpsandare an example of a “plurality of pumps” of the present disclosure.

The primary flow pathis installed in the housing. The primary flow pathis a pipe for the primary refrigerant Cin the CDU. The primary flow pathmainly includes pipesand, and the inflow port, the flow path, and the outflow portdescribed above.

The pipeconnects the primary inflow portand the inflow port. The pipeconnects the outflow portand the primary outflow port. The primary flow pathmay include a joint or a valve in addition to the pipesand

The secondary flow pathis provided to the housingand the pumpsand. That is, the housinghas the secondary flow path. The secondary flow pathis an example of a “fluid flow path” in the present disclosure. The secondary flow pathis a pipe for the secondary refrigerant Cin the CDU. The secondary flow pathmainly includes pipesto, tee jointsA andB, socketsC toF of the coupling, plugsG toJ of the coupling, pump statorsK andL, and the inflow port, the flow path, and the outflow portdescribed above.

Each of the tee jointsA andB has a first connection port, a second connection port, and a third connection port. In each of the tee jointsA,B, 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 socketsC toF have the same specification. For example, the plugsG toJ have the same specification. The socketsC toF are detachably connected to the plugsG toJ, respectively. Each of the socketsC toF has a valve that opens when each of the plugsG toJ is attached. Each valve closes when each of the plugsG toJ is detached from each of the socketsC toF.

Pumpsandcan be further connected to the secondary flow path. In, two pumpsandare illustrated. However, the number of pumps may be plural.

The pumpincludes the plugsG andH, pipesand, a pump statorK, a pump controller, and a pump rotor and a pump motor (not illustrated) as elements. The pump statorK has a suction port, a discharge port, and a cavity (not illustrated). In the pump, 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. When the pump rotor rotates, the fluid flows into the cavity from the suction port of the pump statorK, and the fluid is pressure-fed from the discharge port of the pump statorK.

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

The pumpincludes plugsandJ, pipesand, a pump statorL, a pump controller, and a pump rotor and a pump motor (not illustrated) as elements. The pumpis similar to the pumpin terms of elements. Therefore, detailed description of the pumpwill be omitted.

The pipeconnects the secondary inflow portand the inflow port. The pipeconnects the outflow portand the first connection port of the tee jointA. The pipeconnects the second connection port of the tee jointA and the socketC. The pipeconnects the plugG and the suction port of the pump statorK. The pipeconnects the discharge port of the pump statorK and the plugH. The pipeconnects the socketD and the first connection port of the tee jointB.

The pipeconnects the third connection port of the tee jointA and the socketE. The pipeconnects the plugI and the suction port of the pump statorL. The pipeconnects the discharge port of the pump statorL and the plugJ. In this manner, the pumpsandare connected to the secondary flow path. The pipeconnects the socketF and the second connection port of the tee jointB.

The pipeconnects the third connection port of the tee jointB and the secondary outflow port

The power supplyis installed in the housing, or attachable to or detachable from the housing. The power supplyincludes a power supply circuit and the like. An AC voltage is supplied from an external power supply to the power supply. The external power supply is, for example, a commercial power supply or an uninterruptible power supply device. The power supplygenerates 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 pumpsand. The second DC voltage is supplied to, for example, the main body controllerand the pump controllersand

The operation displayis, for example, a touch screen. The touch screen includes a touch panel and a touch sensor. The operation displaydisplays various images under the control of the main body controller.

The main body controlleris an integrated circuit including electronic circuits such as a microcomputer and a memory (not illustrated). The main body controlleris an example of a “control device” of the present disclosure. Each microcomputer controls elements of the CDUand the pump systemaccording to a program stored in the memory.

The transmission pathincludes cablesandand connectorsandas elements. The cableconnects an input/output terminal of the main body controllerand the connector. The cableconnects an input/output terminal of the pump controllerand the connector. The connectorsandare detachable from each other, and electrically connect or electrically disconnect the cablesandfrom each other.

The transmission pathincludes cablesandand connectorsandas elements. The transmission pathis similar to the transmission pathin terms of elements. Therefore, detailed description of the transmission pathwill be omitted.

As illustrated in, the housinghas openingsandas an example of the “opening” of the present disclosure. In the first example embodiment, the housinghas a substantially rectangular parallelepiped shape. The openingsandare formed side by side in the exterior body of the housing. Accommodation spacesandextend in the first direction Dfrom the openingsandtoward the inside of the housing. Each of the accommodation spacesandhas a shape capable of accommodating each of the pumpsand

The housinghas partition wallsandthat partition the accommodation spacesand. The partition wallsandextend substantially parallel to the first direction D. The partition wallsandare provided with guide rails (not illustrated) capable of guiding the pumpsandin the first direction Dand the second direction Dthat is the opposite direction of the first direction D. When viewed from the opening, the socketsC andD and the connectorare located at the back of the accommodation spacein the first direction D. When viewed from the opening, the socketsE andF and the connectorare located at the back of the accommodation spacein the first direction D.