JP2012159072A - Compressor driving apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-cost and reliable compressor driving apparatus wherein an overload detection device has also high detection precision, while reducing man hours of mounting the overload detection device on a compressor.SOLUTION: The compressor driving apparatus separately from the compressor 47 is stored in a storage case 1. In addition, a first temperature sensor 35 is mounted on the storage case 1 and the storage case 1 is mounted on the outline of the compressor 47. The apparatus thereby is designed to stop an operation of the compressor 47 when a temperature of the compressor 47 detected by the first temperature sensor 35 reaches a predetermined temperature or higher. As a result, the overload detection device is not required to be separately mounted on the compressor 47.

Description

  The present invention relates to a compressor driving device that drives a compressor of a cooling system mounted on a refrigerator or the like.

  Conventionally, a cooling system such as a refrigerator has been equipped with a compressor. In particular, an inverter compressor requires a separate driving device, and detects the temperature of the compressor to energize the compressor driving device. The overload protection device to be stopped is attached to the outer shell of the compressor (see, for example, Patent Document 1).

  Hereinafter, the conventional compressor driving apparatus will be described with reference to the drawings.

  FIG. 4 is a block diagram showing circuit connection of a conventional compressor drive device described in Patent Document 1, and FIG. 5 is an exploded perspective view showing attachment of a conventional overload protection device to a compressor. .

  4 and 5, the compressor driving device 100 has a rectifying circuit 100a and a driving circuit 100b inside.

  The inverter-type compressor 104 is welded with a bracket 104a formed by bending a metal plate on the outer shell, and is provided with three connection terminals 104b at the center position of the bracket 104a.

  The overload protection device 108 that detects the temperature of the compressor 104 is closely attached to the bracket 104a. When the temperature exceeds a predetermined temperature, the internal contact is opened, and the compressor driving device 100 of the AC power source 112 is opened. It is connected so that energization to is cut off.

  The cluster terminal 116 connects the compressor driving device 100 and the connection terminal 104b.

  The cover 120 is attached to the bracket 104a so as to cover the overload protection device 108 and the cluster terminal 116, and the detection accuracy of the temperature detection of the compressor 104 is improved so that the wind does not directly hit the overload protection device 108. I am letting.

  About the compressor drive device comprised as mentioned above, the operation | movement is demonstrated below.

  The compressor driving device 100 uses the AC power source 112 as a power source, and switches the DC voltage rectified and smoothed by the internal rectifying circuit 100a by the driving circuit 100b so that the compressor 104 is energized. Is controlled to rotate at a desired rotational speed.

  When the compressor driving device 100 operates, the compressor driving device 100 generates heat, and when the compressor 104 is overloaded, the temperature becomes even higher.

  Since the overload protection device 108 is closely attached to the bracket 104a, the heat generated by the compressor 104 is conducted to the overload protection device 108, and the temperature of the overload protection device 108 is a predetermined temperature (for example, 100 ° C.). If it becomes above, the internal contact of the overload protection device 108 will be in an open state.

  When the overload protection device 108 is in the open state, the power supply to the compressor driving device 100 is cut off, so the compressor 104 stops and the temperature of the compressor 104 does not rise any further.

  The compressor 104 is safely driven by the operation as described above.

  In addition to the above-described conventional example, there is also a compressor driving device that does not have a rectifier circuit and uses a DC power source as a power source.

  Such a configuration increases the cost, but in a vehicle-mounted compressor drive device, the reliability is improved, the size is reduced, and the compressor drive device is integrated into the compressor.

JP 2006-226248 A

  However, the conventional configuration described above requires a work for attaching the overload protection device 108 to the compressor 104, which increases the number of work steps and also requires the cover 120.

  The present invention solves the above-described conventional problems, and reduces the number of steps for attaching the overload protection device to the compressor while being separate from the compressor, and the temperature of the overload protection device without requiring a cover. An object of the present invention is to provide an inexpensive and highly reliable compressor driving device that can improve detection accuracy.

  In order to solve the above-described conventional problems, a compressor driving device of the present invention stores a printed circuit board that drives a compressor in a storage case, and a first temperature sensor is attached to the storage case or the interior thereof. By being attached to the outer shell of the compressor, the first temperature sensor detects the temperature of the compressor and is configured to stop the operation of the compressor when the temperature exceeds a predetermined temperature. There is no need to separately attach the load protection device to the compressor, and the cover of the overload protection device is also unnecessary.

  Since the compressor drive device of the present invention does not require the overload protection device to be individually attached to the compressor, it is possible to reduce the number of installation steps of the overload protection device, and does not require a cover of the load protection device, The temperature detection accuracy of the overload protection device can also be improved, and an inexpensive and highly reliable compressor drive device can be provided.

1 is an exploded perspective view of a compressor driving device according to Embodiment 1 of the present invention. The side view of the state which attached the compressor drive device in Embodiment 1 to the compressor Circuit block diagram of compressor driving apparatus according to Embodiment 1 Circuit block diagram of conventional compressor drive The exploded perspective view which showed the attachment to the compressor of the conventional load protection device

According to the first aspect of the present invention, a printed circuit board on which a semiconductor element for driving the compressor and a control circuit for controlling the driving of the compressor are mounted, a storage case for storing the printed circuit board, and a storage case or attached therein. A first temperature sensor is provided, and the storage case is attached to the outer shell of the compressor so that when the first temperature sensor detects the temperature of the compressor and exceeds a predetermined temperature, the compressor is operated. It is intended to stop.

  Accordingly, it is not necessary to individually attach the overload protection device to the compressor, and it is possible to provide an inexpensive compressor driving device without requiring a cover for the load protection device.

  According to a second aspect of the present invention, in the first aspect of the invention, the first temperature sensor is attached to the wall surface of the storage case capable of conducting heat with the outer shell of the compressor.

  Thereby, the temperature of the compressor can be detected with higher accuracy, and a more reliable compressor driving device can be provided.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the storage case has a second temperature sensor, and when the second temperature sensor temperature is high, the first temperature sensor The temperature of the compressor stop of the temperature sensor is increased.

  As a result, the temperature in the storage case is detected by the second temperature sensor, and the influence of the temperature in the storage case can be eliminated when the first temperature sensor detects the temperature of the compressor. A compressor drive device that can detect the temperature of the compressor and has higher reliability can be provided.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the microcomputer of the control circuit is reset when the first temperature sensor becomes a predetermined temperature or higher. The operation of the compressor is stopped by maintaining the state.

  As a result, it is possible to provide a more reliable compressor driving device against unexpected factors such as abnormal operation due to a bug in the microcomputer software and malfunction of the microcomputer due to external noise.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is an exploded perspective view of a compressor driving device according to an embodiment of the present invention, FIG. 2 is a side view of the compressor driving device according to the first embodiment attached to the compressor, and FIG. 1 is a circuit block diagram of a compressor driving device according to Embodiment 1. FIG.

  1 to 3, an opening 9 that is slightly larger than the size of the printed circuit board 5 is accommodated in a storage case 1 that is injection-molded with a resin such as a modified polyphenylene ether resin. And a plurality of mounting legs 1c and 1d provided with holes for mounting the compressor driving device.

  The printed circuit board 5 has a glass cloth / glass nonwoven fabric epoxy resin with a copper foil pattern formed on the surface thereof, and a plurality of electronic components are soldered and mounted to form a rectifier circuit 2 and a control circuit 3. Further, a connector 13 for connection, a connector 14 and a connector 15 are also mounted. A plurality of substrate mounting holes 5a are provided at four corners.

  The storage case 1 is formed with an open cord lead-out portion 17 for pulling out the cords from the connector 13, the connector 14, and the connector 15, and is closed by attaching the cover 11 after the cord is drawn out. It is like that.

  Projecting portions 1a projecting toward the opening 9 are integrally formed at four locations inside the storage case 1, and a cylindrical rubber bush 19 having a hollow portion is provided on the projecting portion 1a. The projecting portions 1a are attached so as to be fitted into the hollow portions of the rubber bushes 19, respectively.

  The height of the protruding portion 1 a is higher than the height of the rubber bush 19, and the tip protrudes from the rubber bush 19. The protruding portion fits into the board mounting hole 5 a of the printed board 5. ing. The rubber bush 19 is sandwiched between the storage case 1 and the printed circuit board 5 in a state where the printed circuit board 5 is stored and attached to the storage case 1.

  In each corner 9 of the opening 9 of the storage case 1, mounting holes 1 b are formed, and holes 21 a are formed in the corners of the pressed aluminum alloy aluminum plate 21. The aluminum plate 21 is fixed to the storage case 1 with a plate fixing screw 25 so that the opening 9 can be closed.

  An insulating sheet 29 is attached to the inner surface of the aluminum plate 21 with a fixing screw 31 (for example, two sheets are stacked), and this insulating sheet 29 has an electrical insulating performance (for example, a safety standard) 1750V, withstand a dielectric strength test of 1 minute).

  A semiconductor element 3a such as an IPM (intelligent power module) for driving a compressor, which is a component constituting the control circuit 3, is mounted on the printed circuit board 5, but only the semiconductor element 3a includes a connector 13 and the like. It is mounted on a mounting surface facing the aluminum plate 21 on the side opposite to the other parts.

  The semiconductor element 3a is in close contact with the aluminum plate 21 to which the insulating sheet 29 is attached. By attaching the aluminum plate 21 to the storage case 1, the printed circuit board 5 puts the rubber bush 19 in a compressed state.

  A sensor mounting portion 1e for attaching the first temperature sensor 35, which is a thermistor, is integrally formed at the bottom of the storage case 1, and the first temperature sensor 35 is inserted and mounted. The first temperature sensor 35 is connected to the connector 13 by a cord 35a.

  A second temperature sensor 38 that is a thermistor is mounted on the printed circuit board 5. The cluster terminal 40 is connected to the connector 14 by a cord 42. The power cord 44 is connected to the AC power source 45.

  The hermetic compressor 47 has a connection terminal 47a on its outer wall, and a bracket 51 formed by bending a metal plate is attached by welding.

  The storage case 1 is attached to the compressor 47 by arranging the storage case 1 in a direction in which the bottom of the storage case 1 faces the bracket 51, and fixing the mounting leg 1 c to the bracket 51 with the mounting screw 55.

At this time, the sensor mounting portion 1 e is in close contact with the bracket 51 and can conduct heat with the compressor 47 via the bracket 51. The cluster terminal 40 is connected to the connection terminal 47a.

  Next, an electric circuit of the compressor driving device will be described.

  In FIG. 3, the microcomputer 3 b controls the switching operation of the semiconductor element 3 a that drives the compressor 47.

  The output of the reset IC 3d is electrically connected to the reset terminal 3ba of the microcomputer 3b.

  The comparator 3e has a −input terminal and a + input terminal. A voltage divided by the first temperature sensor 35 and the fixed resistor 3f is input to the −input terminal, and a second temperature sensor 38 is input to the + input terminal. Electrical connection is made so that the divided voltage of the fixed resistor 3g is inputted.

  Further, the output of the comparator 3e is electrically connected to the reset terminal 3ba of the microcomputer 3b, similarly to the output of the reset IC 3d.

  The low voltage DC power supply circuit 3c converts the rectified power supply from the rectifier circuit 2 into a low voltage DC power supply (for example, DC5V), and its output terminal is electrically connected to the power supply terminals of the semiconductor element 3a, the microcomputer 3b, the reset IC 3d, and the comparator 3e. It is connected.

  About the compressor drive device comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  When the semiconductor element 3a performs a switching operation and drives the compressor 47 in accordance with a command from the microcomputer 3b, the semiconductor element 3a generates heat, but the generated heat is transferred to the aluminum plate 21 that is in close contact with the storage case 1. Heat is released to the outside.

  When the compressor 47 is operated, the temperature of the compressor 47 also rises. At the same time, the temperature of the bracket 51 rises in the same manner, and the temperature of the first temperature sensor 35 attached to the storage case 1 is the same. To rise.

  When the temperature of the first temperature sensor 35 rises, the resistance value of the first temperature sensor 35 decreases, so that the input voltage at the negative input terminal of the comparator 3e increases accordingly. When the compressor 47 is overloaded, if the input voltage at the − input terminal becomes higher than the voltage at the + input terminal, the output voltage of the comparator 3e becomes LOW output (0V).

  When the output voltage of the comparator 3e becomes LOW output (0V), the reset terminal 3ba voltage of the microcomputer 3b also becomes 0V. Therefore, the microcomputer 3b is in a reset state and all operations are stopped, and the compressor 47 Operation stops.

  As described above, in the first embodiment, since the first temperature sensor 35 is attached to the storage case 1 in advance, it does not require the man-hour for attaching the temperature sensor to the compressor 47 again. Therefore, it is possible to provide an inexpensive compressor driving device without requiring a cover.

  Further, the first temperature sensor 35 has a structure capable of conducting heat with the compressor 47 via the bracket 51 and the storage case 1, and more accurately detects the temperature of the compressor 47 so that the excess of the compressor 47 can be detected. It is possible to provide a highly reliable compressor driving device that has the effect of being able to perform a load protection operation.

  Now, when the temperature of the second temperature sensor 38 increases, the voltage at the + input terminal also increases. Therefore, the temperature of the first temperature sensor 35 at which the output voltage of the comparator 3 e switches to 0 V is the second temperature sensor 38. The higher the temperature of the temperature sensor 38, the higher the temperature.

  Thus, the temperature of the first temperature sensor 35 that stops the compressor 47 by temperature protection is corrected in a higher direction as the temperature of the second temperature sensor 38 increases.

  Here, although the first temperature sensor 35 is attached so as to detect the temperature of the compressor 47, it is naturally affected by the temperature in the storage case 1. For example, when the voltage of the AC power supply is low, the input current increases, the heat generation of the rectifier circuit 2 increases, and the temperature in the storage case 1 increases accordingly. For this reason, even if the temperature of the compressor 47 is constant, the first temperature sensor 35 becomes high. Conversely, when the voltage is high, the first temperature sensor 35 is at a lower temperature.

  However, in the first embodiment, since the second temperature sensor 38 is mounted on the printed circuit board 5 and detects the temperature in the storage case 1, the temperature in the storage case 1 varies. Even so, the correction by the second temperature sensor 38 has the effect that the temperature of the compressor 47 to be stopped for temperature protection can be made constant, ensuring the stability of temperature detection and ensuring reliability. A high compressor driving device can be provided.

  In the first embodiment, as a means for stopping the compressor 47 by temperature protection, the microcomputer 3b that controls the drive is in a reset state, so that abnormal operation due to a software bug in the microcomputer 3b, Unexpected factors such as malfunction of the microcomputer 3b due to external noise can be eliminated, and a highly reliable compressor driving device can be provided.

  As described above, the compressor driving device according to the present invention can secure the temperature detection stability of the overload protection device while reducing the number of steps for mounting the overload protection device to the compressor. It can also be applied to other devices used.

DESCRIPTION OF SYMBOLS 1 Storage case 3 Control circuit 3a Semiconductor element 3b Microcomputer 5 Printed circuit board 35 1st temperature sensor 38 2nd temperature sensor 47 Compressor

Claims (4)

A printed circuit board on which a semiconductor element for driving the compressor and a control circuit for controlling the drive are mounted, a storage case for storing the printed circuit board, and a first temperature sensor attached to the storage case or the interior thereof. The storage case is attached to the outer shell of the compressor so that when the first temperature sensor detects the temperature of the compressor and exceeds a predetermined temperature, the compressor is stopped. Machine drive device. The compressor driving device according to claim 1, wherein the first temperature sensor is attached to a wall surface of the storage case capable of conducting heat with the outer shell of the compressor. The storage case has a second temperature sensor, and when the temperature of the second temperature sensor is high, the compressor stop temperature of the first temperature sensor is increased. The compressor drive device described. The compressor operation is stopped by maintaining the microcomputer of the control circuit in a reset state when the first temperature sensor becomes a predetermined temperature or higher. The compressor driving device according to one item.