Patent ID: 12230777

The term “temperature control circuit” is to be understood, in the sense of this disclosure, to be a delivery circuit for a temperature control medium. The medium to be delivered can be a water-based coolant which contains additives, such as glycol or another anti-freeze agent. The manner of operation of the temperature control circuit is not limited to a cooling function. Thus, the temperature control circuit can also provide a heating function using a heat source e.g. in a start-up phase of a system or when the ambient temperature is low.

The terms “feeder line” and “return line” of the temperature control circuit relate to how the battery storage module of which the temperature is to be controlled is viewed. Consequently, the feeder line of the temperature control circuit is connected to the outlet opening of the pump and the return line of the temperature control circuit is connected to the inlet opening of the pump.

In a temperature control circuit, a plurality of battery storage modules can be connected with a flow passing through them in parallel or in succession. Furthermore, a temperature control circuit can connect a plurality of temperature control devices and a plurality of pumps.

The term “temperature control source (58)” relates in the sense of this disclosure to an atmosphere or convective air flow of the system environment, to a cold source with a coolant or a heat source, such as an electric heating element. The corresponding temperature control sources (58) are in thermal contact with the temperature control medium in the temperature control circuit via a heat exchanger, such as a radiator with ribs or the like.

In the sense of this disclosure, the term “screw pump” is understood to mean skew rotary piston pumps with a thread pitch for displacement of a medium to be delivered. Such types of pump generally comprise a driven screw spindle and at least one further screw spindle which is entrained therewith via engagement of the toothing.

In the case of the temperature control device which is shown inFIG.1, a pump1is arranged in an integrated manner within a temperature control circuit50. The temperature control circuit50serves to control the temperature of a battery storage module5, in particular to discharge waste heat, which arises during charging or power drain, by means of a temperature control medium—delivered by the pump1—via a heat exchanger, not shown. In the following application, the battery storage module5, not shown in more detail, is a traction battery for a battery-electric vehicle. The temperature control circuit50comprises a plurality of channels with a small cross-section which are in thermal contact with a multiplicity of battery cells of the battery storage module5.

In the embodiment of the schematic illustration ofFIG.1, in a spindle housing10of the pump1, a driven screw spindle2aand an entrained screw spindle2bare received in a rotatable manner in a spindle chamber12of the spindle housing10. A cross-sectional contour of the spindle chamber12is formed by two bores in the spindle housing10, with overlapping radii, in order to ensure engagement of the screw spindles2a,2b. An open side of the spindle chamber12is delimited by a feather key18. The feather key18is formed flat as an end-surface chamber wall of the spindle chamber12and has an inlet opening16of the spindle housing10. The feather key18is inserted into the spindle housing10through a mounting slot perpendicularly to the screw spindles2a,2b.

The screw spindles2a,2bare mounted in a floating manner by a radial clearance fit with respect to the cross-sectional contour of the spindle chamber12and by an axial clearance fit of the spindle chamber12. During pump operation, the spindles are pressed against the feather key18by the displacement process. The feather key18serves as a bearing shield with respect to the axial sliding bearing of the end surfaces of the screw spindles2a,2b.

A pressure side of the spindle chamber12, which communicates with an outlet opening17of the spindle housing10, is located on the drive side of the screw spindles2a,2b, which is depicted on the right. A suction side of the spindle chamber12is located on the other side of the screw spindles2a,2bon which the feather key18is disposed. The suction side of the spindle chamber12communicates with the inlet opening17of the spindle housing10.

The spindle housing10forms, with the screw spindles2a,2b, an insertable pump head60which is inserted into an accommodation housing15of the temperature control device from an axial end of the spindle housing10, towards which the inlet opening16is directed, up to a housing flange14which is connected to the opposing axial end of the spindle housing10. The accommodation housing15is an integral component of the temperature control device, of the pump1and of the temperature control circuit50. The accommodation housing15can also be an integral component of a module housing of the battery storage module5, in which the temperature control circuit50is continued in the form of integrated channels.

The accommodation housing15comprises an opened cavity11which receives the spindle housing10up to the housing flange14. A return line56and a feeder line57of the temperature control circuit50open into the cavity11. The feeder line57opens into a peripheral surface of the cavity11. The cavity11surrounds the spindle housing10in such a way than an annular part of the cavity11is exposed where it overlaps with the outlet opening17and the mouth of the feeder line57. The exposed part of the cavity11produces a pressure-side connection between the spindle housing10and the temperature control circuit50.

The return line56opens into an end-face base surface of the opened cavity11and is allocated, in an opposing arrangement, to the inlet mouth16at the axial end of the inserted spindle housing10. A sealing element4surrounds the mouth of the return line56and the inlet mouth16so that a suction-side connection is produced between the temperature control circuit50and the spindle housing10. The sealing element4further surrounds a periphery of the spindle housing10in the area of the assembly slot, through which the feather key18is introduced. Therefore, a possible leakage flow along a plug-in fit of the feather key18is sealed. In the exposed cavity11, a sealing ring19is introduced into groove-like radial free space upstream of the housing flange14in order to seal the pressure side of the pump1to the outside.

The driven screw spindle2ais connected to an electric motor3. On the pressure side of the spindle chamber12, the spindle housing10comprises an aperture for a shaft32which is driven by the electric motor3. A motor housing13, in which the electric motor3is arranged, is connected on the opposing side of the housing flange14. An internal stator33of the electric motor3is located on a collar portion of the housing flange14. An external pot-shaped rotor35surrounds the stator33and is connected to one end of the shaft32. A bearing seat for a shaft bearing31is formed internally on the collar portion of the housing flange14. The shaft bearing31is a sliding bearing which is sealed at both axial ends and is filled with a lubricant. The other end of the shaft32is coupled to the driven screw spindle2aby means of a plug-in connector23which allows axial clearance.

The motor housing13comprises a separated motor chamber, in which the dry-running electric motor3and an electronic system, in particular power electronics34for switching the electric power at the electric motor3, are received. The stator33comprises field coils which are actuated by the power electronics34and supplied with electric power. The stator33is in thermal contact with the peripheral surface of the collar portion of the housing flange14. Thus, waste heat from the field coils of the stator33is diverted via the housing flange14to the accommodation housing15and the spindle housing10and is absorbed by the temperature control circuit passing therethrough. The power electronics34are likewise in thermal contact with the end surface of the housing flange14in order to discharge waste heat from the electronic components into an area of the temperature control circuit, through which a flow passes.

The temperature control device is considered hereunder in a delivery direction of the temperature control circuit50in order to control the temperature of the battery storage module5. A liquid medium to be delivered is sucked into the spindle chamber12from the return line56of the temperature control circuit50through the seal4and the inlet opening16of the spindle housing10on the suction side. A rotational movement of engaged screw profiles of the rotating screw spindles2a,2bgenerates a negative pressure on the suction side of the spindle chamber12and a positive pressure on the opposing pressure side of the spindle chamber12. The temperature control medium is delivered by continuous displacement along a screw pitch of the engaged screw profiles and ejected from the spindle chamber12through the outlet opening17of the spindle housing10. Downstream of the outlet opening17, the temperature control medium flows via the cavity11into the feeder line57of the temperature control circuit50and to the battery storage module5.

Thereafter, the temperature control medium in the battery storage module5flows through a branching arrangement of channels of the temperature control circuit50, which are formed in the accommodation housing15of the temperature control device and are in thermal contact with the battery cells of the battery storage module5. The temperature control medium then flows through a heat exchanger and discharges waste heat, which was absorbed by the battery cells of the battery storage module5, to a cooler medium, such as e.g. the ambient air, and is sucked back into the pump1. A flow can also pass through the battery storage module5and the heat exchanger in the temperature control circuit50in the reverse order. Furthermore, the temperature control device50can additionally have a further temperature control source58, such as a heating element, through which the temperature control circuit50passes.

LIST OF REFERENCE NUMERALS

1Pump2aDriven screw spindle2bEntrained screw spindle3Electric motor4Seal5Battery storage module10Spindle housing11Cavity12Spindle chamber13Motor housing14Housing flange15Accommodation housing16Inlet opening of the spindle housing17Outlet opening of the spindle housing18Feather key19Sealing ring23Plug-in connector31Shaft bearing32Shaft33Stator34Power electronics35Rotor50Temperature control circuit56Return line of the temperature control circuit57Feeder line of the temperature control circuit