JP2007162629A - Electric pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric pump enabling the peel-off of a rotary body adhered to a pump chamber while suppressing the size. <P>SOLUTION: A pump chamber 15 is demarcated in a housing of an electric roots pump 10. A drive rotor 29 and a driven rotor 30 are stored in the pump chamber 15. An electric motor M rotating the drive rotor 29 and the driven rotor 30 is stored in the housing. A clutch mechanism 31 capable of engaging and disengaging the transmission of power from the electric motor M to the drive rotor 29 is disposed on the power transmission route between the electric motor M and the drive rotor 29. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electric pump that sucks fluid into a pump chamber by rotating a rotating body with an electric motor and further transfers the fluid in the pump chamber to the outside of the pump chamber.

  In general, a fuel cell system includes a fuel cell, an oxygen supply means, and a hydrogen supply means. The fuel cell reacts oxygen supplied from the oxygen supply unit and hydrogen supplied from the hydrogen supply unit to generate (electrically generate) DC electric energy (DC power). The oxygen supply means includes a compressor for supplying compressed air to the fuel cell (see, for example, Patent Document 1), and the hydrogen supply means has a hydrogen source and hydrogen gas that has not been used in the fuel cell. A hydrogen circulation path for re-supplying (so-called hydrogen off-gas) to the fuel cell is provided. The hydrogen circulation path is provided with a pump for transferring the hydrogen off gas toward the fuel cell.

As a pump used for the hydrogen circulation path, for example, a roots type pump is used. This Roots type pump has a pair of rotors housed in a rotor chamber formed in a housing. Each of the pair of rotors is fixed to a rotating shaft. In the Roots-type pump having the above-described configuration, when the pair of rotors are rotated with the rotation of the motor, hydrogen off-gas is sucked into the rotor chamber. Further, the hydrogen off-gas sucked into the rotor chamber is discharged out of the rotor chamber by the rotation of the pair of rotors. Then, the hydrogen off-gas transferred by the pumping action of the Roots pump is mixed with the hydrogen gas newly supplied from the hydrogen source to be re-supplied to the fuel cell.
JP-A-2005-207328

  However, water is generated with the power generation of the fuel cell, and the water is discharged from the fuel cell together with the hydrogen off gas, and further introduced into the rotor chamber together with the hydrogen off gas. When the fuel cell system is operated in a low temperature environment, the water introduced into the rotor chamber is condensed, and condensation is formed between the axial end surface of the rotor and the inner wall surface of the rotor chamber (housing) or on the outer surface of the rotor. To do. Further, when the fuel cell system is stopped from the operating state under a low temperature environment such as below freezing point, the condensed water freezes, and the axial end surface of the rotor and the inner wall surface of the rotor chamber are fixed due to the freezing. Sometimes. As described above, when the axial end surface of the rotor and the inner wall surface of the rotor chamber are stuck, the rotor is peeled off from the inner wall surface of the rotor chamber when the operation of the fuel cell system is resumed. Need to be generated. As a result, in the roots type pump, it is necessary to mount a large motor that can generate a large torque at the time of start-up, and the physique has been enlarged.

  The present invention has been made paying attention to such problems existing in the prior art, and its purpose is to peel off the rotating body fixed to the pump chamber while suppressing an increase in size. An object of the present invention is to provide an electric pump that can be used.

  In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that a pump chamber is defined in the housing, a rotating body is accommodated in the pump chamber, and the housing is further provided in the housing. An electric motor that rotates the rotating body is housed, and the fluid is sucked into the pump chamber by rotating the rotating body by the electric motor, and the fluid in the pump chamber is further transferred to the outside of the pump chamber. In this electric pump, a clutch mechanism capable of intermittently transmitting power from the electric motor to the rotating body is provided on a power transmission path between the electric motor and the rotating body.

  According to this configuration, when the electric pump is started in a state where the rotating body and the pump chamber are fixed, the power transmission from the electric motor to the rotating body is interrupted by the clutch mechanism, and the electric motor is driven in the interrupted state. Furthermore, when the electric motor rotates at a high speed, the moment of inertia generated in the electric motor is rotated by stopping the driving of the electric motor and allowing the clutch mechanism to transmit power from the electric motor to the rotating body. Can be transmitted to the body. Then, a large torque is generated in the rotating body by the moment of inertia, and the rotating body is rotated by the torque, and the rotating body fixed to the pump chamber can be peeled off by this rotation. Therefore, when starting the electric pump in a state where the rotating body and the pump chamber are fixed, it is necessary to generate only the torque (starting torque) necessary for rotating the non-fixed rotating body in the pump chamber. The fixed rotating body can be peeled off. As a result, when starting the electric pump, in addition to the torque for rotating the non-fixed rotating body (starting torque), it is necessary to generate torque for the electric motor to peel off the rotating body fixed to the pump chamber. The torque generated at startup can be reduced. That is, in order to peel off the rotating body from the pump chamber, it is not necessary to generate a large torque in the electric motor, and the increase in size of the electric motor can be suppressed, and consequently the increase in size of the electric pump can be suppressed.

  The electric motor is provided with an output shaft so as to be integrally rotatable, and the rotating body is provided with a rotary shaft rotatably supported by the housing so as to be integrally rotatable, the output shaft and the rotary shaft. And the power transmission path is constituted by the output shaft and the rotary shaft, and the power transmission from the output shaft to the rotary shaft is configured to be intermittent by the clutch mechanism. The output shaft, the rotating shaft, and the clutch mechanism may be accommodated in a housing.

According to this structure, the physique of an electric pump can be made compact compared with the case where an output shaft, a rotating shaft, and a clutch mechanism are provided in the outer side of the housing of an electric pump, for example.
The output shaft may be provided with a weight that rotates integrally with the output shaft.

  According to this configuration, by providing a weight on the output shaft, the ability (inertia moment) to rotate the output shaft with the rotation of the electric motor can be increased, as compared to a case where no weight is provided. The moment of inertia can be further increased. For this reason, the torque generated when the moment of inertia is transmitted to the rotating body via the clutch mechanism can be increased as compared with the case where no weight is provided, and the rotating body can be easily detached from the pump chamber. Can do.

  In addition, the electric pump includes the hydrogen in a fuel cell system including a hydrogen circulation path that allows hydrogen gas that has not been used in the fuel cell to be combined with hydrogen gas supplied from a hydrogen source and supplied to the fuel cell. It may be a roots pump for hydrogen circulation constituting the circulation path.

  According to this configuration, when the electric pump is used for the hydrogen circulation path, water generated by the power generation of the fuel cell enters the pump chamber, and the water condenses in the pump chamber in a low temperature environment, and below freezing point. Freezing increases the possibility of icing (adhering) the rotating body and the pump chamber. However, by providing the clutch mechanism in the electric pump, it is possible to remove the fixed state by peeling the rotating body from the pump chamber while suppressing an increase in the size of the electric motor, and hence the electric pump. Therefore, in the electric pump, the configuration in which the clutch mechanism is provided between the electric motor and the rotating body is particularly effective for use in an electric pump for hydrogen circulation in which the rotating body and the pump chamber are easily fixed due to freezing. .

  ADVANTAGE OF THE INVENTION According to this invention, the rotary body fixed to the pump chamber can be peeled off, suppressing the enlargement of a physique.

  Hereinafter, an embodiment in which the electric pump of the present invention is embodied as an electric roots type pump will be described with reference to FIGS. 1 and 2. In the following description, for the “front” and “rear” of the electric roots pump, the direction of the arrow Y shown in FIG.

  As shown in FIG. 2, the electric roots pump 10 of the present embodiment circulates hydrogen gas (so-called hydrogen off-gas) as a fluid that has not been used in the fuel cell 51 in the fuel cell system 50 provided in the fuel cell vehicle. It is used as a pump for use.

  As shown in FIG. 1, in the housing of the electric roots pump 10 of this embodiment, a gear housing 14 is joined and fixed to the front end (left end in FIG. 1) of the rotor housing 13, and the front end (FIG. 1) of the gear housing. , The motor housing 17 is joined and fixed to the left end). The rotor housing 13 is joined and fixed to the rear end (right end in FIG. 1) of the gear housing 14 and the first housing 13a joined and fixed to the rear end (right end in FIG. 1) of the first housing 13a. 2 housing 13b and a third housing 13c joined and fixed to the rear end (right end in FIG. 1) of the second housing 13b. In the rotor housing 13, a pump chamber 15 is defined between the first housing 13a and the second housing 13b.

  A gear chamber 16 is defined between the gear housing 14 and the first housing 13 a of the rotor housing 13. A motor chamber 18 is defined between the motor housing 17 and the gear housing 14. The motor chamber 18 accommodates an electric motor M having an output shaft 11, and the output shaft 11 is rotatably supported by the motor housing 17 via a bearing 22.

  The electric motor M includes a stator 19 fixed to the inner surface of the motor housing 17 and a rotor 20 that can rotate integrally with the output shaft 11 and can rotate relative to the stator 19. The stator 19 has a stator coil 19a, and the stator coil 19a is electrically connected to an external power source (not shown) through a plurality of lead wires (not shown). The output shaft 11 is press-fitted into the rotor 20 and can rotate integrally with the rotor 20. When a current flows from the external power source to the stator coil 19a, the rotor 20 is rotated by the electromagnetic induction action between the stator coil 19a and the rotor 20, and the output shaft 11 rotates integrally with the electric motor M. .

  Further, brass weights 34 are fixed to the front and rear sides of the rotor 20 along the axial direction of the output shaft 11 so as to be integrally rotatable with the output shaft 11. The weight 34 is provided to increase the magnitude of inertia with respect to the rotation of the electric motor M, that is, to increase the moment of inertia, and to make it difficult to change the rotational motion of the electric motor M (output shaft 11).

  In the housing of the electric roots type pump 10, a drive shaft 24 as a rotation shaft is rotatably supported by a first housing 13 a and a second housing 13 b via a bearing 23. The drive shaft 24 is supported so as to be located on the same axis as the output shaft 11. Furthermore, a driven shaft 25 that is parallel to the drive shaft 24 is rotatably supported by the first housing 13 a and the second housing 13 b via a bearing 26.

  A drive gear 27 fixed to the drive shaft 24 and a driven gear 28 fixed to the driven shaft 25 are accommodated in the gear chamber 16 in a meshed state. The drive shaft 24 and the driven shaft 25 are gear-connected by a drive gear 27 and a driven gear 28. In the pump chamber 15, a drive rotor 29 as a rotating body fixed to the drive shaft 24 and a driven rotor 30 as a rotating body fixed to the driven shaft 25 are accommodated. The drive rotor 29 and the driven rotor 30 are two-leaf type rotors having a cross-sectional view perpendicular to the axial direction of the drive shaft 24 and the driven shaft 25 formed in a double leaf shape (saddle shape).

  In the drive rotor 29, a slight gap is formed between the front and rear end faces along the axial direction of the drive shaft 24 and the inner wall surface of the pump chamber 15. In the driven rotor 30, a slight gap is formed between the front and rear end surfaces along the axial direction of the driven shaft 25 and the inner wall surface of the pump chamber 15. The gap prevents the seizure or the like from occurring due to sliding contact between the front and rear end faces of the drive rotor 29 and the inner wall surface of the pump chamber 15, and the front and rear end faces of the driven rotor 30 and the inner wall surface of the pump chamber 15. A small gap is provided to further reduce off-gas leakage. The rotor housing 13 (second housing 13b) discharges the fluid sucked into the pump chamber 15 to a suction port (not shown) for sucking fluid into the pump chamber 15 and a position opposite to the suction port. A discharge port (not shown) is formed.

  In the motor chamber 18, a clutch mechanism 31 that allows or blocks power transmission from the electric motor M to the drive rotor 29 is disposed between the output shaft 11 of the electric motor M and the drive shaft 24. Yes. The clutch mechanism 31 is formed of a known friction type electromagnetic clutch. When the electromagnetic clutch is turned on (energization of the coil), the output shaft 11 of the electric motor M and the drive shaft 24 are connected to each other. Power (rotation) is transmitted to the drive shaft 24 via the output shaft 11 and the clutch mechanism 31. On the other hand, the output shaft 11 of the electric motor M and the drive shaft 24 are not connected and the power of the electric motor M is not transmitted to the drive shaft 24 when the electromagnetic clutch is turned off (the coil is not energized). When the electromagnetic clutch in the clutch mechanism 31 is on, the drive shaft 24 is rotated by the power transmission from the output shaft 11 to the drive shaft 24.

  In the electric roots-type pump 10 configured as described above, when the electromagnetic clutch in the clutch mechanism 31 is in an on state, the drive shaft 24 is rotated by the power of the electric motor M, so that the drive gear 27 and the driven gear 28 are meshed. The driven shaft 25 rotates in a different direction from the drive shaft 24 through the connection. Then, in the pump chamber 15, the drive rotor 29 and the driven rotor 30 rotate synchronously. With the synchronous rotation of the drive rotor 29 and the driven rotor 30, hydrogen gas as a fluid is sucked into the pump chamber 15 from the suction port. Thereafter, the outer surfaces of the drive rotor 29 and the driven rotor 30 and the inner surface of the pump chamber 15 cooperate to discharge (transfer) the hydrogen gas sucked into the pump chamber 15 out of the pump chamber 15 from the discharge port. The

  Next, the fuel cell system 50 will be described with reference to FIG. FIG. 2 schematically shows the fuel cell system 50. The fuel cell system 50 includes a fuel cell 51, an oxygen supply means 52, and a hydrogen supply means 53. The fuel cell 51 is composed of, for example, a solid polymer type fuel cell, and reacts oxygen supplied from the oxygen supply unit 52 with hydrogen supplied from the hydrogen supply unit 53 to generate DC electric energy (DC power). appear. The oxygen supply means 52 includes a compressor 54 for supplying compressed air. The compressor 54 is connected to an oxygen supply port (not shown) of the fuel cell 51 via a pipe 55, and is in the middle of the pipe 55. A humidifier 56 is provided.

  The hydrogen supply means 53 includes the electric roots type pump 10 of the present embodiment as a hydrogen circulation pump for circulating and using hydrogen gas (so-called hydrogen off gas) that has not been used in the fuel cell 51. In other words, the electric roots pump 10 is provided to supply the hydrogen off gas to the fuel cell 51 again. The electric Roots type pump 10 is connected to a hydrogen supply port (not shown) of the fuel cell 51 via a conduit 58 and connected to a hydrogen discharge port (not shown) of the fuel cell 51 via a conduit 59. Yes. The hydrogen supply means 53 includes a hydrogen tank 60 as a hydrogen source (hydrogen gas supply source). The hydrogen tank 60 is connected to a pipe line 58 through a pipe line 57 provided with a regulator (not shown) on the way. The electric roots pump 10 and the pipes 58 and 59 constitute a hydrogen circulation path that can supply hydrogen gas that has not been used in the fuel cell 51 to the fuel cell 51 together with hydrogen gas newly supplied from the hydrogen tank 60. Has been.

  When the fuel cell system 50 is in an operating state and the electric roots pump 10 having the above-described configuration is in an operating state, hydrogen off-gas containing water generated in the fuel cell 51 is supplied from an inlet through a pipe 59. It is sucked into the pump chamber 15 and discharged from the discharge port to the outside of the pump chamber 15. In a low temperature environment, the water is condensed on the inner wall surface of the pump chamber 15 and the wall surfaces of the drive rotor 29 and the driven rotor 30. Furthermore, when the fuel cell system 50 is stopped from the operating state under freezing and the drive rotor 29 and the driven rotor 30 are stopped, the water in the pump chamber 15 is frozen, and the freezing causes both the front and rear ends of the drive rotor 29 and the driven rotor 30 to be frozen. The surface and the inner wall surface of the pump chamber 15 are frozen and fixed to each other.

  When the electric roots pump 10 is started when the operation of the fuel cell system 50 in the fixed state is resumed, first, the electromagnetic clutch in the clutch mechanism 31 is turned off (the coil is de-energized), and the output shaft 11 of the electric motor M is turned on. And power transmission between the drive shaft 24 and the drive shaft 24 are interrupted. Thereafter, in the electric motor M, a current is supplied from an external power source to the stator coil 19a, and the rotor 20 is rotated by electromagnetic induction between the stator coil 19a and the rotor 20 to generate a starting torque, and the output shaft 11 is rotated. . At this time, since the weight 34 is fixed to the output shaft 11, the rotation speed of the electric motor M is further accelerated by the weight 34 as the rotation speed (power) of the electric motor M increases. Then, with the electric motor M rotating at a high speed, the electromagnetic clutch in the clutch mechanism 31 is turned on (energization of the coil) and at the same time, the energization of the stator coil 19a is stopped.

  Then, the power (moment of inertia (inertia force)) generated in the electric motor M is transmitted to the drive shaft 24 via the clutch mechanism 31 and the output shaft 11, and a large torque is generated on the drive shaft 24 based on the inertia moment. To do. The generated torque is transmitted to the driven shaft 25, and further to the drive rotor 29 and the driven rotor 30 through the meshing connection of the drive gear 27 and the driven gear 28.

  The drive rotor 29 and the driven rotor 30 are rotated by the torque. That is, the drive rotor 29 and the driven rotor 30 are rotated while the electric motor M is stopped. As a result, the ice fixed between the axial end surface of the drive rotor 29 and both front and rear end surfaces of the driven rotor 30 and the inner wall surface of the pump chamber 15 is crushed, and the drive rotor 29 and the driven rotor 30 are connected to the pump chamber 15. As well as being peeled off from the inner wall surface, the fixed state of the drive rotor 29 and the driven rotor 30 and the pump chamber 15 is eliminated. Then, after the drive rotor 29 and the driven rotor 30 are peeled off from the pump chamber 15, the electric motor M is restarted and the electric roots pump 10 is operated.

According to the above embodiment, the following effects can be obtained.
(1) The clutch mechanism 31 is provided on the power transmission path between the electric motor M and the drive rotor 29 so that the power transmission from the electric motor M to the drive rotor 29 can be interrupted. Then, after the electric motor M is stopped, power transmission is permitted by the clutch mechanism 31 to rotate the drive rotor 29 and the driven rotor 30 by the inertia moment (inertial force) of the stopped electric motor M. The rotors 29 and 30 fixed to the inner wall surface of the pump chamber 15 can be peeled off from the inner wall surface of the pump chamber 15. As a result, when the electric roots pump 10 is started, it is fixed to the inner wall surface of the pump chamber 15 only by generating torque for rotating the drive rotor 29 that is not fixed to the pump chamber 15, that is, starting torque. The driven rotor 29 and the driven rotor 30 can be peeled off from the pump chamber 15. Therefore, when the electric roots pump 10 is started, it is not necessary to generate torque for peeling the drive rotor 29 and the driven rotor 30 from the pump chamber 15 in addition to the starting torque of the electric roots pump 10. As a result, in the electric roots type pump 10, it is not necessary to mount a large electric motor M that generates a large torque in order to peel off the drive rotor 29 and the driven rotor 30 from the pump chamber 15. The increase in size of 10 can be suppressed.

  (2) The clutch mechanism 31 and the power transmission path (the output shaft 11 and the drive shaft 24) are provided in the housing (in the motor chamber 18). Therefore, for example, the physique of the electric roots type pump 10 can be made compact compared with the case where the clutch mechanism 31 and the power transmission path are provided outside the housing of the electric roots type pump 10.

  (3) The weight 34 is provided on the output shaft 11 so as to be integrally rotatable. For this reason, the moment of inertia of the electric motor M can be increased by the weight 34, and the rotation of the output shaft 11 can be made difficult to drop. Therefore, when the power of the electric motor M is transmitted to the drive rotor 29 by the clutch mechanism 31, a large torque can be generated by the drive shaft 24, and the drive rotor 29 and the driven rotor 30 can be reliably connected from the inner wall surface of the pump chamber 15. Can be peeled off.

  (4) The electric roots type pump 10 is used for a hydrogen circulation path in the fuel cell system 50 and transfers hydrogen off-gas. When the electric Roots type pump 10 is used for the hydrogen circulation path, water generated by the power generation of the fuel cell 51 enters the pump chamber 15, and the drive rotor 29, the driven rotor 30 and the pump chamber 15 are in a low temperature environment. And are more likely to stick due to freezing. However, by providing the clutch mechanism 31 in the electric roots pump 10, the drive rotor 29 and the driven rotor 30 can be peeled off from the pump chamber 15 without increasing the size of the electric motor M. Therefore, the configuration in which the clutch mechanism 31 is provided in the electric roots type pump 10 is particularly effective when employed in the pump for the hydrogen circulation path of the fuel cell system 50.

In addition, you may change the said embodiment as follows.
(Circle) you may use the electric roots type pump 10 of embodiment as the compressor 54 in the oxygen supply means of a fuel cell system.

  O You may use the electric roots type pump 10 of embodiment as a vacuum pump used for a semiconductor manufacturing apparatus, for example. In this case, the driving rotor 29 and the driven rotor 30 are fixed to the pump chamber 15 by deposits that are deposited by cooling the gas used in the semiconductor manufacturing apparatus. The drive rotor 29 and the driven rotor 30 can be peeled off without increasing the size of the motor M.

  In the embodiment, a clutch mechanism 31 capable of intermittently transmitting power from the electric motor M to the drive rotor 29 may be provided between the rotor 20 and the drive shaft 24 instead of the output shaft 11 of the electric motor M. . In this case, when the clutch mechanism 31 is turned on (energization of the coil), the rotor 20 of the electric motor M and the drive shaft 24 are connected to allow power transmission between the electric motor M and the drive shaft 24. It is good.

In the embodiment, energization and de-energization of the coil may be repeated a plurality of times, and power transmission permission and interruption by the clutch mechanism 31 may be repeated a plurality of times.
In embodiment, it is good also as the electric roots type pump 10 using the multi-leaf or more multi-leaf drive rotor 29 and the driven rotor 30.

  In the embodiment, the electromagnetic clutch of the clutch mechanism 31 is of a friction type. However, the clutch mechanism 31 is changed to an electromagnetic gap type clutch such as an electromagnetic powder clutch or an electromagnetic meshing clutch such as an electromagnetic tooth clutch. It may be used.

In the embodiment, a multistage electric roots pump in which a plurality of drive rotors 29 and driven rotors 30 are attached and fixed in the axial direction of the drive shaft 24 and the driven shaft 25 may be used.
In the embodiment, the electric pump is embodied in the electric roots type pump 10 using the drive rotor 29 and the driven rotor 30 as a rotating body, but the electric pump is embodied in an electric screw type pump using a screw rotor as a rotating body. May be.

In the embodiment, the weights 34 are provided on both the front and rear sides of the rotor 20 along the axial direction of the output shaft 11. However, the weights 34 may be provided on either one of the front and rear sides, and the weight 34 may not be provided.
Next, the technical idea that can be grasped from the above embodiment and other examples will be described below.

(1) A pump chamber is defined in the housing, a rotating body is accommodated in the pump chamber, and an electric motor for rotating the rotating body is accommodated in the housing. A method for starting an electric pump that sucks fluid into the pump chamber by rotating the rotating body with an electric motor, and further transfers the fluid in the pump chamber to the outside of the pump chamber,
The electric pump includes a clutch mechanism capable of intermittently transmitting power from the electric motor to the rotating body on a power transmission path between the electric motor and the rotating body, and transmits power by the clutch mechanism. After shutting off, driving only the electric motor, stopping the electric motor when the electric motor reaches high speed rotation, allowing power transmission by the clutch mechanism, and rotating the rotating body by the inertial force of the electric motor An electric pump starting method characterized by driving an electric motor.

The plane sectional view showing the electric roots type pump of an embodiment. The block diagram of a fuel cell system.

Explanation of symbols

  M is an electric motor, 10 is a hydrogen circulation pump that constitutes a hydrogen circulation path, and is an electric roots pump as an electric pump, 11 is an output shaft that constitutes a power transmission path, 13 is a rotor housing that constitutes a housing, DESCRIPTION OF SYMBOLS 14 ... Gear housing which comprises a housing, 15 ... Pump chamber, 17 ... Motor housing which comprises a housing, 24 ... Drive shaft as a rotating shaft which comprises a power transmission path, 29 ... Drive rotor as a rotary body, 30 ... Rotation A driven rotor as a body, 31 ... a clutch mechanism, 34 ... a weight, 50 ... a fuel cell system, 51 ... a fuel cell, 58, 59 ... pipes constituting a hydrogen circulation path, 60 ... a hydrogen tank as a hydrogen source.

Claims (4)

A pump chamber is defined in the housing, a rotating body is accommodated in the pump chamber, and an electric motor for rotating the rotating body is accommodated in the housing. An electric pump configured such that by rotating the rotating body, fluid is sucked into the pump chamber, and further, the fluid in the pump chamber is transferred to the outside of the pump chamber,
An electric pump, wherein a clutch mechanism capable of intermittently transmitting power from the electric motor to the rotating body is provided on a power transmission path between the electric motor and the rotating body. The electric motor is provided with an output shaft so as to be integrally rotatable, and the rotary body is provided with a rotary shaft that is rotatably supported by the housing. The output shaft and the rotary shaft are The power transmission path is configured by the output shaft and the rotating shaft, and the power transmission from the output shaft to the rotating shaft is configured to be intermittent by the clutch mechanism. The electric pump according to claim 1, wherein the shaft, the rotating shaft, and the clutch mechanism are accommodated in a housing. The electric pump according to claim 2, wherein the output shaft is provided with a weight that rotates integrally with the output shaft. The electric pump includes a hydrogen circulation path of a fuel cell system including a hydrogen circulation path that allows hydrogen gas that has not been used in a fuel cell to be combined with hydrogen gas supplied from a hydrogen source and supplied to the fuel cell. The electric pump according to any one of claims 1 to 3, wherein the electric pump is a roots pump for circulating hydrogen.

Images