JP2005330899A - Belt drive type air compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a belt drive type air compressor capable of preventing a belt from being broken by detecting the free turning state of the belt. <P>SOLUTION: This belt drive type air compressor comprises a motor 3 transmitting a power to a compressor body 4 through the V-belt 16, a delivery side pressure sensor 8 installed on the delivery side of the compressor body 4 and detecting the delivery pressure P1 of the compressor body 4, a suction side pressure sensor 9 installed on the suction side of the compressor body 4 and detecting the suction pressure P2 of the compressor body 4, and a controller 10 stopping the motor 3 by outputting control signals to, for example, a second motor control relay 39 to open a contact when the compressor body 4 is detected to be in a stop state by detection signals from the delivery side pressure sensor 8 or the suction side pressure sensor 9 and the contact of, for example, a first motor control relay 38 is detected to be in a closed state to detect that the motor 3 is in a drive state. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a belt-driven air compressor including a compressor body that is driven by transmission of power from an electric motor via a belt.

  In recent years, from the advantage of low noise, the orbiting scroll member provided with the substantially spiral wrap is swung with respect to the fixed scroll member provided with the substantially spiral wrap corresponding to the wrap of the orbiting scroll member, and the air is Compressor main body (scroll compressor) for compression, motor (electric motor) for generating driving force for swinging the orbiting scroll member, detection means for detecting the pressure of compressed air by the compressor main body, and this detection means According to the detection result, an air compressor including a motor control unit that drives the motor when the pressure of the compressed air becomes less than a predetermined value and stops the motor when the pressure exceeds the predetermined value is proposed. (For example, refer to Patent Document 1). For example, in an air compressor having a medium capacity of 55 kW or less, a V-belt is widely used as a means for transmitting motor power to the compressor body.

JP 2004-60554 A

However, the following problems exist in the above-described conventional technology.
That is, in the V belt, the tension at the time of operation decreases with respect to the tension at the time of assembly due to the initial and subsequent aging, but the amount of decrease varies considerably. Therefore, it is necessary to check and re-tension the V-belt as part of maintenance, but if this is not done, the V-belt slips and the power transmission efficiency decreases, and the compressor body The amount of discharged air decreases. If the tension of the V belt further decreases, the compressor main body may not be driven even though the motor is driven, and only the V belt may slip (idle) with respect to the pulley on the compressor main body side. . Further, when the compressor body is locked for some reason, the V-belt may be idle. In such a case, frictional heat is generated between the pulley on the compressor body side and the V-belt, and the V-belt may be cut.

  An object of the present invention is to provide a belt-driven air compressor capable of detecting a belt idle state and preventing the belt from being broken.

  (1) In order to achieve the above object, the present invention provides a compressor body that compresses air, an electric motor that transmits power to the compressor body via a belt, and whether the compressor body is in a driven state or a stopped state. A compressor main body detecting means for detecting whether the motor is in a driving state or a stopped state, and a compressor main body detecting means for stopping the compressor main body. And stopping means for stopping the electric motor when the electric motor detecting means detects that the electric motor is in a driving state.

  In the present invention, when the compressor main body detecting means detects the stop state of the compressor main body and the motor detecting means detects the driving state of the motor, that is, when the belt is idle with respect to the pulley of the compressor main body. Then, the motor is stopped by the stopping means. Thereby, it is possible to detect the idle state of the belt and prevent the belt from being broken.

  (2) In the above (1), preferably, the compressor main body detection means includes a discharge side detection means that is provided on a discharge side of the compressor main body and detects a discharge pressure or a discharge flow rate of the compressor main body. .

  (3) In the above (1) or (2), preferably, the compressor main body detection means is provided on a suction side of the compressor main body, and detects a suction pressure or a suction flow rate of the compressor main body. It has a detection means.

  (4) In the above (1), preferably, the compressor main body detecting means is a displacement detecting means for detecting a change in position of an operating part in the compressor main body.

  According to the present invention, it is possible to detect the idle state of the belt and prevent the belt from being broken.

  Embodiments of the present invention will be described below with reference to the drawings.

  A first embodiment of the present invention will be described with reference to FIGS.

  FIG. 2 is a longitudinal sectional view showing a schematic structure of one embodiment of the belt-driven air compressor of the present invention, and FIG. 3 shows a compressor constituting one embodiment of the belt-driven air compressor of the present invention. It is a horizontal sectional view showing the detailed structure of a main part.

2 and 3, a belt-driven air compressor 1 includes a housing 2 that forms an outer shell and a skeleton thereof, and a motor (electric motor) known as this type that is fixed on a base 2a in the housing 2. ) 3, a compressor main body 4 that is fixed to the support member 2 b in the housing 2 and compresses air, and a cooling fan 5 that attracts outside air into the housing 2 to cool the motor 3, the compressor main body 4, and the like. A heat exchanger 6 that cools the compressed air from the compressor body 4 to an appropriate temperature, a dryer 7 that dehumidifies the compressed air from the heat exchanger 6 to an appropriate humidity, and a discharge side of the compressor body 4 (this In the embodiment, provided on the downstream side of the heat exchanger 6 and provided on the suction side of the compressor body 4 and the discharge side pressure sensor 8 for detecting the discharge pressure P ₁ of the compressor body 4, the compressor body 4 a suction side pressure sensor 9 for detecting the suction pressure P _2, which ejection And a control unit 10 controls the driving of the motor 3 according to the detection result of the side pressure sensor 8 and the suction-side pressure sensor 9 (see FIG. 1 below).

  The cooling fan 5 has a rotating shaft connected to one side (left side in FIG. 2) of the motor rotating shaft 3 a and is driven together with the rotation driving of the motor 3. Then, by driving the cooling fan 5, as indicated by an arrow A in FIG. 2, outside air flows into the housing 2 from the intake port 11 </ b> A and is discharged from the exhaust port 13 </ b> A through the cooling fan 5 and the duct 12. Yes. Thereby, the motor 3 and the compressor body 4 in the housing 2 are cooled by the outside air. At the same time, as indicated by an arrow B in FIG. 2, the outside air from the intake port 11B is caused to flow out to the heat exchanger 6 provided in the duct 12 through the cooling fan 5, and then discharged from the exhaust port 13A. doing. Thereby, the heat exchanger 6 cools the compressed air from the compressor body 4 to an appropriate temperature.

  The dryer 7 is a heat pump type refrigeration cycle provided with a compressor 7a, a condenser 7b, a capillary 7c, and an evaporator 7d, so that the compressed air from the heat exchanger 6 is dehumidified to an appropriate humidity. It has become. At this time, the dryer 7 is provided with a fan 7e for air-cooling the condenser 7b and the evaporator 7d, and exhausts air from the exhaust port 13B as indicated by an arrow C in FIG.

  The compressor body 4 is provided with a V pulley 14, and, along with the rotation drive of the motor 3, a V pulley 15 provided on the other side (right side in FIG. 2) of the rotation shaft 3 a of the motor 3 and these V pulleys 14, 15 are mounted. Rotational power is transmitted through the mounted V belt 16.

  The compressor body 4 is, for example, a double-tooth scroll compressor that operates in an oil-free state (without lubricating oil) in the compression working chamber. As shown in FIG. 3, the substantially spiral wraps 17a and 17b are attached to the end plate. The orbiting scroll 17 provided on both side surfaces (left and right in FIG. 3) of the 17c and substantially spiral wraps 18a and 19a corresponding to the wraps 17a and 17b of the orbiting scroll 17 (substantially meshed) are provided. The fixed scrolls 18 and 19 provided on the inner side surfaces of the end plates 18b and 19b (the right side of 18b in FIG. 3 and the left side of 19b), one side (the lower side in FIG. 3) of the radially outer peripheral portion of the orbiting scroll member 17, and The main crankshaft 20 and the auxiliary crankshaft 2 are provided with crank portions 20a and 21a connected to the opposite side (upper side in FIG. 3) in the center and swing the orbiting scroll member 17. And the toothed pulleys 22A and 22B provided on one side (the left side in FIG. 3) of the main crankshaft 20 and the auxiliary crankshaft 20, respectively, and the main crankshaft 20 and the auxiliary crank that are stretched over the toothed pulleys 22A and 22B. A timing belt 23 for synchronously rotating the shaft 21 and the pulley 14 provided on one side of the main crankshaft 20 are provided.

  As the orbiting scroll member 17 swings (orbits), the substantially spiral wraps 17a and 17b mesh with the substantially spiral wraps 18a and 19a of the fixed scroll members 18 and 19, respectively. The chambers 24A and 24B are formed, and these compression working chambers 24A and 24B are continuously moved from the radially outer peripheral portion to the inner peripheral portion to reduce the volume thereof. Further, the orbiting scroll member 17 includes the wraps 17a and 17b, the end plate portion 17c, a communication hole 17d provided at the center in the radial direction of the end plate portion 17c and communicating with the compression working chambers 24A and 24B on both sides, and the end plate portion 17c. A plurality of cooling air passages 17e are provided which communicate with the interior in the vertical direction (perpendicular to the paper surface in FIG. 3) and cool the end plate portion 17c.

  The fixed scroll member 18 includes the wrap 18a, the end plate portion 18b, a substantially circular dust strap 18c provided on the outer peripheral side in the radial direction of the wrap 18a of the end plate portion 18b and preventing dust from entering from the outside. A suction port (not shown) provided on the inner side in the radial direction of the strap 18c, a discharge port 18d provided at the center in the radial direction of the end plate portion 18b for discharging the compressed air in the compression working chamber 24A, and an end of the end plate portion 18b The heat dissipating fin 18e is provided on the external side (left side in FIG. 3) side surface. Similarly to the fixed scroll member 18, the fixed scroll member 19 is provided on the radially outer peripheral side of the lap 19a, the end plate portion 19b, and the lap 19a of the end plate portion 19b, and prevents the intrusion of dust from the outside. A dust trap 19c having a shape, a suction port (not shown) provided on the inner side in the radial direction of the dust strap 19c, and a central portion in the radial direction of the end plate portion 19b are discharged from the compression working chamber 24B. A discharge port 19d and a heat dissipating fin 19e provided on the outer side (right side in FIG. 3) side surface of the end plate portion 19b are provided.

  The fixed scroll members 18 and 19 are combined in parallel and fastened with bolts (not shown) or the like to constitute a housing that encloses the orbiting scroll member 17. Cooling air vents (not shown) are provided on the upper and lower surfaces of the fixed scroll members 18 and 19, respectively, and the cooling air described above passes through the vents in the housing (specifically, the fixed scroll members 18). , 19 flows into and out of the outer peripheral side of the dust wraps 18c, 19c and the cooling air passage 17e of the orbiting scroll member 17 to cool the inside of the housing.

  The main crankshaft 20 is rotatably supported by rolling bearings 25A and 26A provided on the fixed scroll members 18 and 19, respectively. Further, balance weights 27 </ b> A and 27 </ b> B are fixedly disposed on the main crankshaft 20 in order to offset the unbalance due to the orbiting movement of the orbiting scroll member 17. The auxiliary crankshaft 21 is rotatably supported by rolling bearings 25B and 26B provided on the fixed scroll members 18 and 19, respectively. In addition, balance weights 28 </ b> A and 28 </ b> B are fixedly disposed on the auxiliary crankshaft 21 in order to cancel out unbalance due to the orbiting motion of the orbiting scroll member 17.

  The crank portion 20a of the main crankshaft 20 and the crank portion 21a of the auxiliary crankshaft 21 are eccentric with the same amount of eccentricity from the axis thereof, and the orbiting scroll member 17 is connected to the crank portions 20a and 21a via rolling bearings 29A and 29B. It is pivotally supported so that it can swivel.

The discharge side pressure sensor 8 is provided in a pneumatic pipe 30 connected between the heat exchanger 6 and the dryer 7, and outputs the detected discharge pressure P ₁ to the control device 10. The discharge-side pressure sensor 8 may be provided, for example, on the upstream side of the check valve 32 in the pneumatic piping 31 connected between the compressor body 4 and the heat exchanger 6. Suction side pressure sensor 9 is provided in the air pipe 34 connected between the suction port of the compressor body 4 and the intake air filter 33, and outputs a suction pressure P ₂ detected in the control unit 10 ing.

  FIG. 3 is a block diagram showing detailed functions of the control device 10 together with peripheral devices.

  In FIG. 3, the control device 10 includes an input unit 35 for inputting detection signals from the discharge side pressure sensor 8 and the suction side pressure sensor 9, a storage unit (ROM) 36 for storing a control processing program, and the storage unit. A control unit (CPU) 37 that performs arithmetic processing based on a program stored in 36, and outputs control signals to the first motor control relay 38 and the second motor control relay 39 in response to a command from the control unit 37. And a motor control circuit 40 for detecting whether the contact of the first motor control relay 38 is open or closed. The motor 3 is connected to the battery 41 via a first motor control relay 38 and a second motor control relay 39 (normally contact points are closed) connected in series.

First, as a first function, the control device 10 performs predetermined arithmetic processing on the detection signal from the discharge-side pressure sensor 8 and outputs the generated control signal to the first motor control relay 38. . In particular, less than the discharge pressure P ₁ is a predetermined value (used minimum pressure, for example whether it is set and stored in the storage unit 36 as a fixed value, or may be set and stored as in each case a fixed value by a suitable external setting means) If this is the case, the contact of the first motor control relay 38 is closed, whereby the motor 3 is energized and driven. The compressor body 4 is driven by the drive motor 3, or the discharge pressure P ₁ is set in the storage unit 36 stores a predetermined value (used maximum pressure, for example, a fixed value, or each time by an appropriate external setting means In this case, the contact of the first motor control relay 38 is opened and the motor 3 is stopped.

Further, as a second function, the control device 10 performs a predetermined calculation process on the detection signal from the suction side pressure sensor 9 and outputs the generated control signal to an alarm device (not shown). ing. Specifically, if the suction pressure P ₂ is smaller than the specified value (in other words, if the differential pressure is greater than a predetermined value), to drive the warning device, an intake filter 33 to notify that the clogged It is like that.

Furthermore, as a major feature of the present embodiment, the control device 10 detects whether the compressor body 4 is in a driving state or a stopped state based on detection signals from the pressure sensors 8 and 9. That is, in the driving state of the compressor body 4, the discharge pressure _{P 1} is the suction pressure _{P 2} greater than atmospheric pressure (about 0.1013 MPa) is smaller than the atmospheric pressure, in the stop state of the compressor body 4, the discharge pressure _{P 1} and suction pressure P ₂ is at or near atmospheric. In addition, the control device 10 detects whether the motor 3 is in a driving state or a stopped state by detecting whether the contact of the first motor control relay 38 is in an open state or a closed state by the motor control circuit 40. Is supposed to be detected. When the compressor main body 4 is in a stopped state and the motor 3 is in a driving state, the contact of the second motor control relay 39 is opened and the motor 3 is stopped. The control procedure of the control device 10 will be described with reference to FIG. FIG. 4 is a flowchart showing the contents of control processing related to the above control of the control device 10.

In FIG. 4, first, at step 100, it is determined whether or not the discharge pressure P ₁ is atmospheric pressure based on a detection signal from the discharge side pressure sensor 8. If the discharge pressure _{P 1} is atmospheric pressure, the determination is satisfied in step 100, proceeds to step 110. On the other hand, if the discharge pressure P ₁ is not atmospheric pressure, the determination is not satisfied in step 100, proceeds to step 120. In step 120, it is determined whether the suction pressure P ₂ is the atmospheric pressure by the detection signal from the suction-side pressure sensor 9. If suction pressure P ₂ is not atmospheric pressure, the determination is not satisfied in step 120, returns to step 100, to repeat the same procedure. On the other hand, when the suction pressure P ₂ is atmospheric pressure, the determination is satisfied in step 120, it proceeds to step 110.

  In step 110, the motor control circuit 40 determines whether or not the contact of the first motor control relay 38 is in a closed state, thereby determining whether or not the motor 3 is in a driving state. If the motor 3 is in a stopped state (in other words, the contact of the first motor control relay 38 is in an open state), the determination in step 110 is not satisfied, and the process returns to step 100 and the same procedure is repeated. On the other hand, when the motor 3 is in the driving state (in other words, the contact of the first motor control relay 38 is in the closed state), the determination in step 110 is satisfied, and the routine proceeds to step 130.

  In step 130, a control signal is output from the motor control circuit 40 to the second motor control relay 39, the contact is opened, and the motor 3 is stopped. Thereafter, returning to step 100, the same procedure as described above is repeated.

  In the above description, the discharge-side pressure sensor 8 is provided on the discharge side of the compressor body described in the claims, constitutes a discharge-side detection means for detecting the discharge pressure of the compressor body, and the suction-side pressure sensor 9 Is provided on the suction side of the compressor body described in the claims, and constitutes suction side detection means for detecting the suction pressure of the compressor body. The discharge-side pressure sensor 8 and the suction-side pressure sensor 9 constitute a compressor body detection unit that detects whether the compressor body is in a driving state or a stopped state.

  The first motor control relay 38 and the control device 10 constitute motor detection means for detecting whether the motor is in a driving state or a stopped state, and the second motor control relay 39 and the control device 10 are a compressor. When the main body detecting means detects that the compressor main body is in a stopped state and the electric motor detecting means detects that the motor is in a driving state, the main body detecting means constitutes a stopping means for stopping the motor.

  Next, the operation and effect of this embodiment will be described.

  In the belt-driven air compressor 1 of the present invention, for example, when used as a factory air source, the motor 3 is driven, and rotational power is transmitted via the pulleys 14 and 15 and the V belt 16 to compress the air. The main crankshaft 20 of the machine body 4 is driven to rotate. Simultaneously with the start of rotation of the main crankshaft 20, rotational power is transmitted through the toothed pulleys 22A and 22B and the timing belt 23, and the auxiliary crankshaft 21 rotates. By rotating the main crankshaft 20 and the auxiliary crankshaft 21 synchronously, the orbiting scroll member 17 is prevented from rotating, and the eccentric amount of the crank portion 20a of the main crankshaft 20 (= auxiliary crankshaft). , And a turning motion having a radius equal to the eccentric amount of the crank portion 21a of 21. As the orbiting scroll member 17 orbits, air flows in from the suction port, and the inflowing air is compressed to a predetermined pressure while reducing its volume toward the center in the compression working chambers 24A and 24B. It discharges from outlet 18d, 19d. The compressed air from the compressor body 4 is cooled to an appropriate temperature by the heat exchanger 6, dehumidified to an appropriate humidity by the dryer 7, and pumped from the belt-driven air compressor 1.

  In such an operation of the belt-driven air compressor 4, the tension may decrease due to the aging of the V-belt 16, and in this case, the compressor main body 4 is driven despite the motor 3 being driven. May not be driven, and only the V belt 16 may slip (idle) with respect to the pulley 14 of the compressor body 4.

Accordingly, in the present embodiment, the control device 10, the suction-side pressure sensor or the discharge pressure P ₁ is at atmospheric pressure, or at step 120 in step 100 of FIG. 4 described above, the detection signal from the discharge-side pressure sensor 8 by suction pressure P ₂ to determine whether the atmospheric pressure by the detection signal from the 9, the compressor main body 4 to detect whether the stop state. In step 110, it is determined whether or not the motor 3 is in a driving state by determining whether or not the contact of the first motor control relay 38 is in a closed state. When the compressor main body 4 is in the stopped state and the motor 3 is in the driven state, that is, when the V-belt 16 is idle with respect to the pulley 14 of the compressor main body 4, in step 130, the second motor control relay A control signal is output to 39, the contact is opened, and the motor 3 is stopped. Thereby, the idling state of the V belt 16 can be detected, and breakage of the V belt 16 can be prevented.

  In the above-described embodiment, the discharge side pressure sensor 8 is provided as the discharge side detection unit, and the suction side pressure sensor 9 is provided as the suction side detection unit. However, the present invention is not limited to this. That is, for example, a pressure switch may be provided in place of the pressure sensors 8 and 9, or a flow sensor for detecting the discharge flow rate and the suction flow rate may be provided, for example. Further, only one of the discharge side detection means and the suction side detection means may be provided. In these cases, the same effect as described above can be obtained.

  In the above-described embodiment, the stop unit for stopping the motor 3 has been described by taking as an example a configuration in which the motor 3 is stopped by opening the contact of the second motor control relay 39. Needless to say, for example, the second motor control relay 39 may not be provided, and the motor 3 may be stopped by opening the contact of the first motor control relay 38.

  A second embodiment of the present invention will be described with reference to FIG.

  The present embodiment is an embodiment in which a displacement detection means for detecting a change in the position of the operating portion in the compressor body 4 is provided as the compressor body detection means.

  FIG. 5 is a longitudinal sectional view showing the detailed structure of the compressor body constituting the belt-driven air compressor according to the present embodiment. In FIG. 5, the same parts as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

  In the compressor main body 4 ′ according to the present embodiment, the fixed scroll member 18 is provided with a position sensor 42 that detects the position change (distance) of the end portion of the orbiting scroll member 17 on the main crankshaft 20 side (lower side in FIG. 5). . The position sensor 42 detects the distance to the main crankshaft side end portion of the orbiting scroll member 17 that periodically changes with the orbiting motion of the orbiting scroll member 17, and outputs the detection signal to the control device 10. . The control device 10 determines whether or not the orbiting scroll member 17 is orbiting based on a detection signal from the position sensor 41, and thereby determines whether or not the compressor body 4 is in a driving state or a stopped state. As in the above embodiment, when it is detected that the compressor body 4 is in the stopped state and the motor 3 is in the driving state, a control signal is output to the second motor control relay 39 to open the contact, The motor 3 is stopped.

  Also in the present embodiment configured as described above, the belt idle state can be detected and the belt can be prevented from being broken, as in the first embodiment.

  In the second embodiment, the position sensor 42 serving as the displacement detection unit has been described by taking an example of a configuration that detects the distance from the end of the orbiting scroll member 17, but is not limited thereto. That is, for example, the distance from the balance weights 27A, 27B (or 28A, 28B) is detected, or, for example, a flat portion is provided on the outer peripheral portion of the main crankshaft 20 or the auxiliary crankshaft 21, and the outer peripheral portion changes with rotational movement. Or the like may be detected. In these cases, the same effect as described above can be obtained.

It is a block diagram showing the detailed function of the control apparatus which comprises 1st Embodiment of the belt drive type air compressor of this invention with a peripheral device. It is a longitudinal section showing a schematic structure of a belt drive type air compressor of a 1st embodiment of the present invention. It is a horizontal sectional view showing the detailed structure of the compressor main body which comprises 1st Embodiment of the belt drive type air compressor of this invention. It is a flowchart showing the control processing content of the control apparatus which comprises 1st Embodiment of the belt drive type air compressor of this invention. It is a horizontal sectional view showing the detailed structure of the compressor main body which comprises 2nd Embodiment of the belt drive type air compressor of this invention.

Explanation of symbols

1 Belt-driven air compressor 3 Motor (electric motor)
4 compressor body 8 discharge side pressure sensor (discharge side detection means, compressor body detection means)
9 Suction side pressure sensor (suction side detection means, compressor body detection means)
10 Control device (motor detection means, stop means)
16 V belt 38 1st motor control relay (electric motor detection means)
39 Second motor control relay (stopping means)
42 Position sensor (displacement detection means, compressor body detection means)

Claims (4)

  A compressor main body that compresses air; an electric motor that transmits power to the compressor main body via a belt; a compressor main body detecting unit that detects whether the compressor main body is in a driving state or a stopped state; and the electric motor A motor detecting means for detecting whether the compressor is in a driving state or a stopped state, and the compressor main body detecting means detects that the compressor main body is in a stopped state and the motor detecting means detects the driving state of the motor. And a stopping means for stopping the electric motor when it is detected that the motor is in a belt-driven air compressor.   2. The belt-driven air compressor according to claim 1, wherein the compressor main body detection means is provided on the discharge side of the compressor main body and detects discharge pressure or discharge flow rate from the compressor main body. A belt-driven air compressor characterized by comprising:   3. The belt-driven air compressor according to claim 1, wherein the compressor body detection means is provided on the suction side of the compressor body, and detects a suction pressure or a suction flow rate of the compressor body. A belt-driven air compressor characterized by comprising means. 2. The belt-driven air compressor according to claim 1, wherein the compressor main body detecting means is a displacement detecting means for detecting a change in position of an operating part in the compressor main body. .

Images