WATERCRAFT

Abstract

A watercraft includes a hull; a deck supported by the hull; a propulsion system supported by the hull and configured to propel the watercraft; an electric motor operatively connected to the propulsion system to drive the propulsion system; a battery electrically connected to the electric motor for powering the electric motor; and a heat exchanger supported by the hull, the heat exchanger having defined therein at least: a first cooling channel, and a second cooling channel, a first cooling circuit being defined in part through the first cooling channel, the first cooling circuit being in thermal communication with at least one of the battery and the electric motor, a second cooling circuit being defined in part through the second cooling channel, the second cooling circuit being in thermal communication with at least an other one of the battery and the electric motor.

Description

FIELD OF TECHNOLOGY

The present technology relates to systems for thermal management in watercraft.

BACKGROUND

The electrification of vehicles is becoming more commonplace in today's market in an effort to offer consumers vehicular options that minimize emissions. For instance, battery-powered watercraft (i.e., electric watercraft) such as personal watercraft (PWC) are now available to consumers that desire an emissions-free watercraft. However, electric watercraft also face different challenges.

The thermal limitations of electric components in an electric watercraft powertrain can vary significantly. Batteries, motors, and various electrical and electronic components can have different working temperatures, with each needing to be managed in order to produce an efficient vehicle performance and component lifetime. While watercraft often take advantage of the body of water in which they operate for cooling, this can be more complicated for electronics and especially in saltwater environments.

In view of the foregoing, there is a need for an electric watercraft which addresses at least in part some of these defects.

SUMMARY

It is an object of the present technology to ameliorate at least some of the inconveniences present in the prior art.

According to aspects of the present technology, there is provided an electric watercraft with two cooling circuits, or cooling loops, for providing thermal management of different electronic components. The present technology includes one closed cooling loop, where heat exchange fluid is circulated and sealed therein, for cooling the battery, and another closed cooling loop for cooling the motor. Both cooling loops or circuits are arranged to transfer heat from the electric components to one heat exchanger. The heat exchanger is shaped, configured, and arranged to also serve as the ride plate of the watercraft, such that the heat exchanger is in direct contact with a body of water during operation. The watercraft also has an open cooling loop, where water from the body of water in which the watercraft is operating is circulated through the loop and back into the body of water. The open cooling loop provides additional cooling to the heat exchanger, and specifically passes between cooling channels in the heat exchanger forming a portion of each of the two closed loops. By spacing the two cooling loops within the heat exchanger, and passing the open cooling channel therebetween, cross-heating of the two loops is reduced. In some embodiments, other electronic components such as the inverter and the charger are cooled by one of the closed loops. Use of a closed cooling loop to provide thermal management to electronic components can reduce long term wear and tear and/or maintenance costs compared to open cooling loops, as there is no possibility of debris or salt intrusion in the closed cooling loop. By using an open cooling loop through the heat exchanger body, the relatively large thermal mass of the body of water is utilized to allow both closed cooling loops to share a common heat exchanger, while being generally thermally isolated from one another and also offer better efficiency of heat transfer from both closed cooling loops.

Vehicle propulsion batteries generally have an optimal and maximal working temperature of around 20° C. and 60° C. respectively, while electric motors generally have optimal and maximal working temperatures of around 30° C. and 170° C. respectively. The higher working temperature of the motor could thus prevent a single cooling loop from properly controlling the temperature of both the motor and the battery. By the present technology, the motor, having a higher maximal working temperature, is removed from the battery's coolant circuit's thermal load. An improved thermal, and vehicle, performance can thus be achieved by separating the closed cooling loops serving each of the motor and the battery.

According to aspects of the present technology, there is provided a watercraft including a hull; a deck supported by the hull; a propulsion system supported by the hull and configured to propel the watercraft; an electric motor operatively connected to the propulsion system to drive the propulsion system; a battery electrically connected to the electric motor for powering the electric motor; and a heat exchanger supported by the hull, the heat exchanger having defined therein at least a first cooling channel, and a second cooling channel, a first cooling circuit being defined in part through the first cooling channel, the first cooling circuit being in thermal communication with at least one of the battery and the electric motor, a second cooling circuit being defined in part through the second cooling channel, the second cooling circuit being in thermal communication with at least an other one of the battery and the electric motor.

In some embodiments, the first cooling circuit is in thermal communication with the electric motor; and the second cooling circuit is in thermal communication the battery.

In some embodiments, the watercraft further includes a charger electrically connected to the battery; and an inverter electrically connected to the battery.

In some embodiments, the first cooling circuit is in thermal communication with the electric motor and at least one of the charger and the inverter; and the second cooling circuit is in thermal communication the battery.

In some embodiments, the first cooling circuit is arranged to transfer, when in operation, heat from the electric motor and the at least one of the charger and the inverter to the heat exchanger; and the second cooling circuit is arranged to transfer, when in operation, heat from the battery to the heat exchanger.

In some embodiments, the first cooling channel extends in a first direction and a second direction through the heat exchanger; a thickness of the first cooling channel being defined along a third direction orthogonal to the first direction and the second direction; the second cooling channel extends in the first direction and the second direction through the heat exchanger; a thickness of the second cooling channel being defined along the third direction; and the second cooling channel is offset from the first cooling channel in the third direction.

In some embodiments, the first cooling channel and the second cooling channel are at least partially aligned along the third direction.

In some embodiments, at least a majority of the first cooling channel is aligned with the second cooling channel along the third direction.

In some embodiments, the second cooling channel is substantially in a same plane as the first cooling channel; and the second cooling channel being offset from the first cooling channel in at least one of the first direction and the second direction.

In some embodiments, the watercraft further includes a first pump forming a portion of the first cooling circuit, the first pump being arranged to cause a first heat exchange fluid to circulate through the first cooling circuit; and a second pump forming a portion of the second cooling circuit, the second pump being arranged to cause a second heat exchange fluid to circulate through the second cooling circuit.

In some embodiments, the first cooling circuit is a closed cooling circuit for circulating the first heat exchange fluid therein; and the second cooling circuit is a closed cooling circuit for circulating the second heat exchange fluid therein.

In some embodiments, the heat exchanger extends at least partially out of the hull; and during operation of the watercraft on a body of water, at least a portion of the heat exchanger is in contact with the body of water.

In some embodiments, the heat exchanger includes a first layer formed of heat conducting material, the first cooling channel being defined in the first layer; and a second layer connected to the first layer, the second layer being formed of heat conducting material, the second cooling channel being defined in the second layer.

In some embodiments, the heat exchanger further includes a heat conducting layer disposed between the first layer and the second layer.

In some embodiments, the heat exchanger further has a third cooling channel defined therein; and the third cooling channel defines a portion of a third cooling circuit.

In some embodiments, during operation of the watercraft on a body of water, the third cooling circuit is arranged to be in fluid communication with the body of water, using surrounding water as heat exchange fluid in the third cooling circuit.

In some embodiments, the third cooling circuit is an open cooling loop.

In some embodiments, the watercraft further includes a third pump forming a portion of the third cooling circuit, the third pump being arranged to cause water from the body of water to circulate through the third cooling circuit.

In some embodiments, the third pump forms a portion of the propulsion system.

In some embodiments, the third cooling channel is disposed between the first cooling channel and the second cooling channel in the heat exchanger.

In some embodiments, the third cooling circuit is arranged to transfer, when in operation, heat from the first cooling circuit and the second cooling circuit to the body of water via the heat exchanger.

In some embodiments, the heat exchanger includes a first layer formed of heat conducting material, the first cooling channel being defined in a first surface of the first layer, the third cooling channel being defined in a second surface of the first layer, the second surface being disposed opposite the first surface; and a second layer connected to the first layer, the second layer being formed of heat conducting material, the second cooling channel being defined in the second layer.

In some embodiments, the heat exchanger further includes a heat conducting layer disposed between the first layer and the second layer.

In some embodiments, the watercraft further includes a straddle seat supported by the deck; and the watercraft is a personal watercraft.

In some embodiments, the heat exchanger is a ride plate connected to the hull.

For purposes of this application, the terms related to spatial orientation such as forwardly, rearward, left and right, are as they would normally be understood by a driver of a vehicle sitting thereon in a normal driving position.

Embodiments of the present technology each have at least one of the above-mentioned objects and/or aspects, but do not necessarily have all of them. It should be understood that some aspects of the present technology that have resulted from attempting to attain the above-mentioned objects may not satisfy these objects and/or may satisfy other objects not specifically recited herein.

Additional and/or alternative features, aspects, and advantages of embodiments of the present technology will become apparent from the following description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present technology, as well as other aspects and further features thereof, reference is made to the following description which is to be used in conjunction with the accompanying drawings, where:

FIG. 1 is a right side elevation view of an electric personal watercraft in accordance with an embodiment of the present technology;

FIG. 2 is a top plan view of the watercraft of FIG. 1;

FIG. 3 is a bottom plan view of the watercraft of FIG. 1;

FIG. 4 is a top, rear, right side perspective view of the watercraft of FIG. 1, with upper portions of the watercraft having been removed;

FIG. 5 is a top plan view of the portions of the watercraft of FIG. 4;

FIG. 6 is a bottom, rear, right side perspective view of the portions of the watercraft of FIG. 4;

FIG. 7 is a top, front, left side perspective view of a power system of the watercraft of FIG. 1;

FIG. 8 is a schematic diagram of cooling systems of the watercraft of FIG. 1;

FIG. 9 is a top, front, right side perspective view of the power system of FIG. 7, with a schematic illustration of the first and second cooling circuits;

FIG. 10 is a schematic illustration of a cooling circuit and a motor of the power system of FIG. 7;

FIG. 11 is a perspective view of a propulsion system and a heat exchanger of the power system of FIG. 7;

FIG. 12 is a top, rear, right side perspective view of the heat exchanger of FIG. 11;

FIG. 13 is a cross-sectional view of the heat exchanger of FIG. 12;

FIG. 14 is a perspective view of the heat exchanger of FIG. 12, with a top layer being removed;

FIG. 15 is a bottom side perspective view of a heat exchange layer of the heat exchanger of FIG. 12;

FIG. 16 is a top perspective view of another heat exchange layer of the heat exchanger of FIG. 12;

FIG. 17 is a perspective view of a propulsion system and a heat exchanger according to another non-limiting embodiment of the present technology;

FIG. 18 is a cross-sectional view of the heat exchanger of FIG. 17;

FIG. 19 is a side view of the propulsion system and the heat exchanger of FIG. 17; and

FIG. 20 is a top view of a portion of a heat exchanger according to another non-limiting embodiment of the present technology.

It should be noted that figures may not be drawn to scale.

DETAILED DESCRIPTION

An electric watercraft 10 in accordance with one embodiment of the present technology is shown in FIGS. 1 to 3. In this embodiment, the electric watercraft 10 is an electric personal watercraft (PWC) 10 (i.e., is powered by electricity). Those of ordinary skill in the art will recognize that other types of electric watercraft could also implement the present technology.

The PWC 10 has a hull 12 and a deck 14 supported by the hull 12. The hull 12 buoyantly supports the PWC 10 in the water. The hull 12 defines a bow 42 and a stern 44 opposite the bow 42, as well as a laterally centered keel 45 (FIG. 3). The deck 14 is designed to accommodate one or multiple riders. The hull 12 and the deck 14 are joined together at a seam 16 that joins the parts in a sealing relationship. A bumper 18 generally covers the seam 16, which helps to prevent damage to the outer surface of the PWC 10 when the PWC 10 is docked, for example.

As shown in FIG. 1, the deck 14 has a centrally positioned straddle-type seat 28 positioned on top of a pedestal 30 to accommodate multiple riders in a straddling position. The seat 28 includes a front seat portion 32 and a rear, raised seat portion 34. The seat 28 is preferably made as a cushioned or padded unit, or as interfitting units. The front and rear seat portions 32, 34 are removably attached to the pedestal 30.

The PWC 10 has a pair of generally upwardly extending walls located on either side of the PWC 10 known as gunwales or gunnels 36. The gunnels 36 help to prevent the entry of water in the footrests 38 of the PWC 10, provide lateral support for the riders' feet, and also provide buoyancy when turning the PWC 10, since the PWC 10 may roll slightly when turning.

Located on both sides of the PWC 10, between the pedestal 30 and the gunnels 36, are the footrests 38 (FIG. 2). The footrests 38 are designed to accommodate the riders' feet in various riding positions. The footrests 38 are covered by carpeting made of a rubber-type material, for example, to provide additional comfort and traction for the feet of the riders. A reboarding platform 40 is provided at the rear of the PWC 10 on the deck 14 to allow the rider or a passenger to easily reboard the PWC 10 from the water. Nonslip mats or some other suitable covering may cover the reboarding platform 40.

As shown in FIG. 1, the PWC 10 is provided with a hood 46 located forwardly of the seat 28 and a helm assembly 60. Rear-view mirrors 62 are positioned on either side of the hood 46 to allow the rider to see behind the PWC 10.

As best seen in FIG. 2, the helm assembly 60 is positioned forwardly of the seat 28. The helm assembly 60 has a central helm portion 64, that is padded, and a pair of steering handles 65, also referred to as a handlebar. One of the steering handles 65 is provided with an acceleration actuator (not shown), which allows the rider to control an electric motor 22 (described below), and therefore the speed of the PWC 10. The acceleration actuator is a finger-actuated actuator, but it is contemplated that the acceleration actuator could be a thumb-actuated lever or a twist grip. The other of the steering handles 65 is provided with a reverse gate operator (not shown) used by the driver to actuate a reverse gate (not shown) of the PWC 10. The reverse gate operator is a finger-actuated lever, but it is contemplated that the reverse gate operator could be a thumb-actuated lever or a twist grip.

With additional reference to FIGS. 4 to 7, a jet propulsion system 50 (also commonly referred to as a “jet pump drive”) and power components, including the motor 22, are supported by the hull 12 and enclosed between the hull 12 and the deck 14. The power components provided power to the motor 22 to drive the jet propulsion system 50. The power components are described in more detail below.

The PWC 10 is propelled by the jet propulsion system 50 which pressurizes water to create thrust. To that end, the jet propulsion system 50 has a duct 52 (FIG. 6) in which water is pressurized and which is defined by various components of the jet propulsion system 50. With additional reference to FIG. 7, the jet propulsion system 50 includes inter alia a ride plate 200, an impeller housing 51, and a steering nozzle 57 of the jet propulsion system 50. A driveshaft 55 is connected between the electric motor 22 and an impeller 70 in the impeller housing 51 of the jet propulsion system 50. A bellow assembly 56 is mounted to the driveshaft 55 and provides a seal between the duct 52 and the hull 12 such as to prevent entry of water into the hull.

As best shown in FIG. 6, the duct 52 has an inlet 86 positioned under the hull 12. When the jet propulsion system 50 is in operation, water is first scooped into an inlet 86. An inlet grate 53 (FIG. 3) is positioned adjacent (i.e., at or near to) the inlet 86 and is configured to prevent large rocks, weeds, and other debris from entering the jet propulsion system 50, which may damage the system or negatively affect performance. It is contemplated that the inlet grate could be positioned in the inlet 86.

With continued reference to FIGS. 4 to 7, the PWC 10 includes a battery 105 in electrical communication with electric motor 22 which stores electrical power for powering the electric motor 22. To manage and charge the battery 105, the PWC 10 also includes a charger 110 electrically connected to the battery 105 and an inverter 112 electrically connected to the battery 105. Additional components of the power system of the electric PWC 10, including but not limited to electrical control units and wiring/cabling, could be included but specific details depend on the particular embodiment.

According to the present technology and illustrated in FIGS. 8 and 9, the PWC 10 includes two cooling circuits, also referred to as cooling loops, for providing thermal management of the electrical components of the PWC 10. In order to respect significantly different thermal limits and manage multiple heat generation profiles across the different electrical components, the battery 105 and the electric motor 22 are cooled by separate cooling circuits.

The PWC 10 includes a first cooling circuit 150 configured to circulate a heat exchange fluid therein, illustrated in FIGS. 8 and 9. The cooling circuit 150 is specifically a closed loop, where the heat exchange fluid circulates within a closed volume and is maintained therein. The choice of heat exchange fluid is not meant to be specifically limiting, and could include, but is not limited to, ethylene glycol, propylene glycol, and mixtures thereof with water.

The cooling circuit 150 includes a variety of tubes and channels for bringing the heat exchange fluid into thermal communication with the electrical components thermally managed by the cooling circuit 150 (described further below). The particular arrangement for fluid flow will depend on the specific embodiment, and thus tubing and channels have been omitted or shown schematically for simplicity. In order to cause the heat exchange fluid to circulate through the cooling circuit 150, the PWC 10 includes a pump 145 (shown schematically) forming a portion of the cooling circuit 150 and being arranged to cause the heat exchange fluid to circulate through the cooling circuit 150.

In order to transfer heat from the heat exchange fluid to the environment, the watercraft 10 also includes a heat exchanger 200 supported by the hull 12. In the present embodiment, the heat exchanger 200 is specifically the ride plate 200. The heat exchanger 200 and the arrangement thereof in the PWC 10 is described in more detail below. Briefly, the heat exchanger 200 has multiple cooling, or heat exchange, channels defined therein through which heat exchange fluid flows when in operation. Defining part of the cooling circuit 150, the heat exchanger 200 includes a cooling channel 210 defined therein. The cooling channel 210, and the heat exchanger 200 more generally, are described in more detail below.

The cooling circuit 150 is arranged to provide thermal management, generally cooling, to some of the electric components of the PWC 10. In the illustrated embodiment, the cooling circuit 150 is in thermal communication with the battery 105. A housing 106 of the battery 105 includes a thermal exchange channel 107 (shown schematically) forming a portion of the cooling circuit 150 and receiving heat exchange fluid therethrough. Different arrangements for providing thermal communication between the heat exchange fluid and the battery 105 are also contemplated.

In the present embodiment, the cooling circuit 150 is further in thermal communication with the charger 110 and the inverter 112. The housings of each of the charger 110 and the inverter 112 include heat exchange channels (not shown), but the arrangement is not meant to be particularly limiting. It is contemplated that additional components of the PWC 10 could be in thermal communication with the cooling circuit 150. It is also contemplated that the charger 110 and the inverter 112 could be thermally managed by a separate or different cooling circuit in some embodiments.

The PWC 10 further includes a second cooling circuit 170, also referred to as the cooling loop 170, configured to circulate a heat exchange fluid therein, illustrated in FIGS. 8 to 10. The cooling circuit 170 is specifically a closed loop, where the heat exchange fluid circulates within a closed volume and is maintained therein. The choice of heat exchange fluid is not meant to be specifically limiting, and could include, but is not limited to, ethylene glycol, propylene glycol, and mixtures thereof with water. It is noted that the cooling circuit 170 is separate from the cooling circuit 150, such that the heat exchange fluids of the circuits 150, 170 do not mix.

The cooling circuit 170 includes a variety of tubes and channels for bringing the heat exchange fluid into thermal communication with the electrical components thermally managed by the cooling circuit 170 (described further below). The particular arrangement for fluid flow will depend on the specific embodiment, and thus tubing and channels have been omitted or shown schematically for simplicity. In order to cause the heat exchange fluid to circulate through the cooling circuit 170, the PWC 10 includes a pump 175 (shown schematically) forming a portion of the cooling circuit 170 and being arranged to cause the heat exchange fluid to circulate through the cooling circuit 170.

As is illustrated in FIG. 10, the cooling circuit 170 is in thermal communication with the electric motor 22. The motor 22 includes a cooling jacket 23 which defines therein a heat exchange channel 24. The channel 24 defines a portion of the cooling circuit 170 and through which heat exchange fluid flows when in operation. Specifically, heat exchange fluid in the closed cooling circuit 170 is pressurized by the pump 175 and thus forced into and through the cooling jacket 23. Different arrangements for thermal communication between the cooling circuit 170 and the motor 22 are contemplated. It is also contemplated that the cooling circuit 170 could be in thermal communication with the charger 110, the inverter 112, and/or other components of the PWC 10 in some embodiments.

The cooling circuit 170 is further partially defined by a cooling channel 220 of the heat exchanger 200. As is further detailed below, the cooling channel 220 is separate and distanced from the cooling channel 210, in order to decrease the chances of heat transferring between the channels 210, 220 before being transferred to the environment by the heat exchanger 200.

With reference to FIGS. 8, 9, and 11, the PWC 10 further includes a third cooling circuit 190, also referred to as the cooling loop 190. The cooling circuit 190 is defined through a portion of the propulsion system 50 and through a cooling, or heat exchange, channel 230 of the heat exchanger 200. As will be described in more detail below, the heat exchange channel 230 is separately defined from the channels 210, 220. The cooling circuit 190 is arranged to transfer heat from the heat exchanger 200 to the environment, specifically such that heat transferred from the cooling circuits 150, 170 into the heat exchanger 200 is transferred to the body of water via the cooling circuit 190. It is contemplated that the open cooling circuit 190 could be omitted in some embodiments.

The cooling circuit 190 is in fluid communication with the body of water during operation of the watercraft, such that water from the body of water circulates in the cooling circuit 190. The cooling circuit 190 is thus an open cooling loop, where water from the body of water flows into, through, and out of the cooling circuit 190, without any recirculation of the water. The particular arrangement for fluid flow through the PWC 10 will depend on the specific embodiment, with one possible embodiment being illustrated in FIG. 11, with some tubing shown schematically. In order to cause water from the body of water to circulate through the cooling circuit 190, the propulsion system 50 forms a portion of the cooling circuit 190 and is arranged to cause water to circulate through the cooling circuit 190. In the present embodiment, pumping action for the circuit 190 is produced by the propulsion system 50, with the housing 51 being in fluid communication with the cooling circuit 190. Specifically in the illustrated embodiment, as the propulsion system 50 pressurizes water flow therethrough for providing vehicle motive power, an aperture 59 of the housing 51 is fluidly connected to the heat exchanger 200 (see FIG. 11), thereby allowing a small portion of the pressurized water to be driven through the cooling circuit 190. Specifically, water driven through the aperture 59 is pumped into and through the channel 230. It is contemplated that the propulsion system 50 could be operatively connected to the channel 230 and the heat exchanger 200 by different arrangements in different embodiments.

The cooling circuit 150 is thus arranged to transfer, when in operation, heat from the battery 105, the charger 110, and the inverter 112 to the body of water via the heat exchanger 200, and the cooling circuit 170 is arranged to transfer, when in operation, heat from the electric motor 22 to the body of water via the heat exchanger 200. As the heat exchanger 200 is in direct contact with the body of water during operation, at least some heat may be transferred directly to the body of water through exterior surfaces of the heat exchanger 200. The cooling circuit 190 is further arranged to transfer heat from the heat exchanger 200 to the body of water, via water from the body of water conducted through the channel 230 through the heat exchanger 200.

With the arrangements of the present technology, heat transfer between vehicle components is mitigated by the separate cooling circuits 150, 170, as the motor 22 generally operates at a significantly higher temperature than the battery 105, the motor 22 being designed to withstand a higher temperature while delivering its specified performance. In contrast, the battery 105 is much more sensitive to higher temperatures, which can be detrimental to its capacity and lifespan. The battery 105 may further not deliver its specified performance unless maintained at a significantly lower temperature (relative to the motor 22). The use of separate cooling circuits 150, 170 thus aids in ensuring that any heat generated by the motor 22 will not raise the temperature of the battery 105, otherwise possible through thermal communication in a shared cooling circuit. In the illustrated embodiment, and as will be described further below, the channel 230 of the open cooling circuit 190 is disposed between the channels 210, 220 of the circuits 150, 170 in order to further aid in thermally separating the cooling circuit 150 of the battery 105 and the cooling circuit 190 of the motor 22.

With reference to FIGS. 12 to 16, the heat exchanger 200 is illustrated in greater detail. As is noted above, the heat exchanger 200 also serves as the ride plate for the PWC 10, and as such is in direct contact with the body of water when the PWC 10 is in operation and extends partially out of the hull 12 (see FIGS. 3 and 6). It is contemplated that a separate and/or additional heat exchanger could be used in some embodiments.

Broadly, the hear exchanger 200 includes two plates defining the cooling channels 210, 220, 230 therein, heat exchange sealing layers on or between the plates, and a plurality of conduits for directing heat exchange fluid or water into and out of the channels 210, 220, 230.

The heat exchanger 200 includes a layer 205 formed from a heat conducting material. In the present embodiment, the layer 205 is specifically a metal plate 205. It is contemplated that a different material or form could be implemented for the layer 205. As can be seen in at least FIG. 14, the cooling channel 210 is defined in the plate 205. With the arrangement of the plate 205 when the heat exchanger 200 is installed in the PWC 10, the cooling channel 210 is specifically defined in a top surface of the plate 205. The plate 205 includes a plurality of fins 211 disposed in the channel 210, the fins 211 being integrally formed with the plate 205. The fins 211 aid in absorbing heat from the heat exchange fluid flowing therebetween and transferring to the mass of the plate 205. While the fins 211 as illustrated form a series of passages through the channel 210, the specific shape and number of fins 211 could vary in different embodiments.

The heat exchange 200 includes two nozzles 212 for directing heat exchange fluid into and out of the channel 210 inside the heat exchanger 200. The nozzles 212 are thus connected to the plate 205 and are fluidly connected to the channel 210 at either end thereof. The nozzles 212 are shaped and configured for operatively connecting to tubing (not shown), but the specific shape and form of the nozzles 212 could vary. It is also contemplated that the nozzles 212 could be omitted in some embodiments, where different arrangement for conducting heat exchange fluid into and out of the channel 210 are provided.

A top heat conducting layer 207 is disposed on the plate 205 in order to seal and generally prevent water infiltration into the channel 210. Scaling a top side of the plate 205 with a heat conducting material may aid in transferring heat from heat exchange fluid in channel 210 to water flowing over the heat exchanger 200 during operation. It is contemplated, however, that the top layer 207 could be formed from a non-heat conducting material or an inefficient heat conducting material in some embodiments. The nozzles 212 extend through the layer 207; additional nozzles 222, 232 (described below) also extend therethrough.

The cooling channel 230 is also defined in the plate 205. In the illustrated arrangement as installed in the PWC 10, the channel 230 is defined on a bottom surface of the plate 205. The plate 205 includes a plurality of fins 231 disposed in the channel 230, the fins 231 being integrally formed with the plate 205. The fins 231 aid in transferring heat from the plate 205 to water flowing therebetween. While the fins 231 as illustrated form a series of passages through the channel 230, the specific shape and number of fins 231 could vary in different embodiments.

The heat exchanger 200 includes two nozzles 232 for directing water into and out of the channel 230 inside the heat exchanger 200. The nozzles 232 are thus connected to the plate 205 and are fluidly connected to the channel 230 at either end thereof. As can be seen from FIG. 14, the nozzles 232 extend from an upper side of the plate 205, parallel to the nozzles 212, such that connections to the nozzles 212, 232 (and thus the channels 210, 230) are on a same side of the heat exchanger 200. The nozzles 232 are shaped and configured for operatively connecting to tubing (shown schematically in FIG. 11), but the specific shape and form of the nozzles 232 could vary. It is also contemplated that the nozzles 232 could be omitted in some embodiments, where different arrangement for conducting water into and out of the channel 230 are provided.

The heat exchanger 200 further includes another layer 215 formed from a heat conducting material. In the present embodiment, the layer 215 is specifically a metal plate 215. It is contemplated that a different material or form could be implemented for the layer 215. The plate 215 is connected to the plate 205, although the particular manner in which the plates 205, 215 are connected together is not meant to be limiting. In the illustrated embodiment, the plates 205, 215 are affixed together using an intermediate heat conducting layer 217 (described below), but it is contemplated that the plates 205, 215 could be fastened together, for example.

As can be seen in at least FIG. 16, the cooling channel 220 is defined in the plate 215. With the arrangement of the plate 215 when the heat exchanger 200 is installed in the PWC 10, the cooling channel 220 is specifically defined in a top surface of the plate 215. In some embodiments, it is contemplated that the channel 220 could be defined in a bottom surface of the plate 215 (with a sealing layer affixed thereto). The plate 215 includes a plurality of fins 221 disposed in the channel 220, the fins 221 being integrally formed with the plate 215. The fins 221 aid in absorbing heat from the heat exchange fluid flowing therebetween and transferring to the mass of the plate 215. While the fins 221 as illustrated form a series of passages through the channel 220, the specific shape and number of fins 221 could vary in different embodiments.

The heat exchanger 200 further includes two nozzles 222 for directing heat exchange fluid into and out of the channel 220 inside the heat exchanger 200. The nozzles 222 are thus connected to the plate 215 and are fluidly connected to the channel 220 at either end thereof. The nozzles 222 are shaped and configured for operatively connecting to tubing (not shown), but the specific shape and form of the nozzles 222 could vary. It is also contemplated that the nozzles 222 could be omitted in some embodiments, where different arrangement for conducting heat exchange fluid into and out of the channel 220 are provided. As can be seen in at least FIG. 14, the nozzles 222 extend through holes or apertures in the plate 205, although it is contemplated that the nozzles 222 may be arranged to avoid the plate 205 in some embodiments.

The heat exchanger 200 further includes a heat conducting layer 217 disposed between the plate 205 and the plate 215. In the present embodiment, the layers 207, 205, 217, 215 are bolted or fastened together (fasteners not shown), with a gasket (not shown) between the plates 205, 215 for sealing the edge therebetween. It is contemplated that the plates 205, 215 could be welded together in at least some embodiments. Other methods for connecting the layers 207, 205, 217, 215 together are also contemplate and are not meant to be specifically limited.

As can be seen from FIG. 14, the cooling channel 210 extends in a first direction and a second direction through the heat exchanger 200, generally forming an “S” or wave-like path within a horizontal plane with the arrangement of the heat exchanger 200 in the PWC 10. A thickness of the cooling channel 210 is defined along a third direction orthogonal to the first direction and the second direction, thus the thickness in the present embodiment is generally measured vertically compared to the horizontal extent of the channel 210 (see FIG. 13). The cooling channel 220 similarly extends in the first direction and the second direction, generally within a horizontal plane (see FIG. 15), through the heat exchanger 200, with a thickness of the channel 220 being defined along the third direction, i.e. vertically. As can be seen in at least FIG. 13, the channel 220 is offset from the channel 210 in the third or vertical direction. As such, the channels 210, 220 extend generally parallel to and distanced from each other. As can further be seen in FIG. 13, the channel 230 of the open cooling circuit 190 is disposed vertically between the channel 210 and the channel 220. The channel 230 has a similar form as the channels 210, 220, and thus serves to separate the channels 210, 220 in a vertical direction.

With all elements of the cooling systems thus defined, the cooling circuits 150, 170, 190 of the illustrated embodiment are arranged as follows. In the cooling circuit 150, heat exchange fluid is pumped by the pump 145 into and through the heat exchange channel 107 of the battery 105, through the cooling channel of the charger 110, through the cooling channel of the inverter 112, into a first one of the nozzles 212, through the channel 210, and out of the other nozzle 212 back to the pump 145. In the cooling circuit 170, heat exchange fluid is pumped by the pump 175 into and through the channel 24 of the motor jacket 23, into a first one of the nozzles 222, through the channel 220, and out of the other nozzle 222 back to the pump 175. Water from the body of water is pressurized by the propulsion system 50 in order to provide motive power to the vehicle. In the cooling circuit 190, a small portion of the water thus pressurized is sent out of the propulsion system housing 51 via the aperture 59 of the housing and into a first one of the nozzles 232, through channel 230 and out of the other nozzle 232, back into the body of water.

It is noted that the direction through which the heat exchange fluid or water passes through the channels 210, 220, 230 is not meant to specifically limiting. In some cases, cross-flow of the heat exchange fluids may be chosen; in some cases, parallel flow may be desired.

Another embodiment of a heat exchanger 300 for use in the PWC 10 according to the present technology is schematically illustrated in FIGS. 17 to 19. Elements of the heat exchanger 300 that are similar to those of the PWC 10 and the heat exchanger 200 retain the same reference numeral and will generally not be described again.

The heat exchanger 300, along with the propulsion system 50, defines an open cooling circuit 310 (shown partially schematically). The heat exchanger 300 includes a layer 305, also referred to as a plate 305, formed from a heat conducting material. As with the plate 205, the plate 305 defines the channel 210 in a top side of the plate 305. The plate 305 also partially defines a cooling or heat exchange channel 330 which forms a portion of the open cooling circuit 310. Using the propulsion system 50, water is circulated into the channel 330 via a nozzle 332. In contrast to channel 230, the channel 330 is open to the body of water out of a rear side of the heat exchanger 300. In such an arrangement, the heat exchanger 300 thus only needs one nozzle 332 and could have a general reduction in the complexity of tubing.

Another embodiment of a heat exchanger 400 for use in the PWC 10 according to the present technology is schematically illustrated in FIG. 20. Elements of the heat exchanger 400 that are similar to those of the PWC 10 and the heat exchanger 200 retain the same reference numeral and will generally not be described again.

The heat exchanger 400 includes one heat conducting layer 405, or plate 405. The plate 405 has defined therein a cooling channel 410 for the closed circuit 150 and a cooling channel 420 for the closed circuit 170. The cooling channel 420 is thus substantially in a same plane as the cooling channel 410. The channels 410, 420 are generally in a same plane in the vertical direction, but the channel 410 is offset from the cooling channel 420 in a lateral direction. Although not illustrated, the cooling channel 230 for the open cooling circuit 190 is defined on an opposite side of the plate 405 to transfer heat from the channels 410, 420 to the body of water via the plate 405 and the cooling circuit 190.

Modifications and improvements to the above-described embodiments of the present technology may become apparent to those skilled in the art. The foregoing description is intended to be exemplary rather than limiting. The scope of the present technology is therefore intended to be limited solely by the scope of the appended claims.

Claims

1. A watercraft comprising: a hull;a deck supported by the hull;a propulsion system supported by the hull and configured to propel the watercraft;an electric motor operatively connected to the propulsion system to drive the propulsion system;a battery electrically connected to the electric motor for powering the electric motor; anda heat exchanger supported by the hull, the heat exchanger having defined therein at least: a first cooling channel, anda second cooling channel,a first cooling circuit being defined in part through the first cooling channel, the first cooling circuit being in thermal communication with at least one of the battery and the electric motor,a second cooling circuit being defined in part through the second cooling channel, the second cooling circuit being in thermal communication with at least an other one of the battery and the electric motor.

2. The watercraft of claim 1, wherein: the first cooling circuit is in thermal communication with the electric motor; andthe second cooling circuit is in thermal communication the battery.

3. The watercraft of claim 1, further comprising: a charger electrically connected to the battery; andan inverter electrically connected to the battery.

4. The watercraft of claim 3, wherein: the first cooling circuit is in thermal communication with the electric motor and at least one of the charger and the inverter; andthe second cooling circuit is in thermal communication the battery.

5. The watercraft of claim 4, wherein: the first cooling circuit is arranged to transfer, when in operation, heat from the electric motor and the at least one of the charger and the inverter to the heat exchanger; andthe second cooling circuit is arranged to transfer, when in operation, heat from the battery to the heat exchanger.

6. The watercraft of claim 1, wherein: the first cooling channel extends in a first direction and a second direction through the heat exchanger;a thickness of the first cooling channel being defined along a third direction orthogonal to the first direction and the second direction;the second cooling channel extends in the first direction and the second direction through the heat exchanger;a thickness of the second cooling channel being defined along the third direction; andthe second cooling channel is offset from the first cooling channel in the third direction.

7. The watercraft of claim 6, wherein the first cooling channel and the second cooling channel are at least partially aligned along the third direction.

8. The watercraft of claim 6, wherein: the second cooling channel is substantially in a same plane as the first cooling channel; andthe second cooling channel being offset from the first cooling channel in at least one of the first direction and the second direction.

9. The watercraft of claim 1, further comprising: a first pump forming a portion of the first cooling circuit, the first pump being arranged to cause a first heat exchange fluid to circulate through the first cooling circuit; anda second pump forming a portion of the second cooling circuit, the second pump being arranged to cause a second heat exchange fluid to circulate through the second cooling circuit.

10. The watercraft of claim 1, wherein: the heat exchanger extends at least partially out of the hull; andduring operation of the watercraft on a body of water, at least a portion of the heat exchanger is in contact with the body of water.

11. The watercraft of claim 1, wherein the heat exchanger comprises: a first layer formed of heat conducting material, the first cooling channel being defined in the first layer; anda second layer connected to the first layer, the second layer being formed of heat conducting material, the second cooling channel being defined in the second layer.

12. The watercraft of claim 11, wherein the heat exchanger further comprises a heat conducting layer disposed between the first layer and the second layer.

13. The watercraft of claim 1, wherein: the heat exchanger further has a third cooling channel defined therein; andthe third cooling channel defines a portion of a third cooling circuit.

14. The watercraft of claim 13, wherein, during operation of the watercraft on a body of water, the third cooling circuit is arranged to be in fluid communication with the body of water, using surrounding water as heat exchange fluid in the third cooling circuit.

15. The watercraft of claim 14, further comprising a third pump forming a portion of the third cooling circuit, the third pump being arranged to cause water from the body of water to circulate through the third cooling circuit.

16. The watercraft of claim 15, wherein the third pump forms a portion of the propulsion system.

17. The watercraft of claim 11, wherein the third cooling channel is disposed between the first cooling channel and the second cooling channel in the heat exchanger.

18. The watercraft of claim 17, wherein the third cooling circuit is arranged to transfer, when in operation, heat from the first cooling circuit and the second cooling circuit to the body of water via the heat exchanger.

19. The watercraft of claim 13, wherein the heat exchanger comprises: a first layer formed of heat conducting material, the first cooling channel being defined in a first surface of the first layer,the third cooling channel being defined in a second surface of the first layer, the second surface being disposed opposite the first surface; anda second layer connected to the first layer, the second layer being formed of heat conducting material, the second cooling channel being defined in the second layer.

20. The watercraft of claim 19, wherein the heat exchanger further comprises a heat conducting layer disposed between the first layer and the second layer.

21. The watercraft of claim 1, further comprising a straddle seat supported by the deck; and wherein the watercraft is a personal watercraft.

22. The watercraft of claim 21, wherein the heat exchanger is a ride plate connected to the hull.