JP5353873B2 - Compressor control device - Google Patents

Abstract

A compressor is provided with: a motor (30); a piston rod (11) which is driven by the motor (30) and reciprocatable within a cylinder (10); a seal member (14) adapted to seal between the piston rod (11) and the cylinder (10); a cold state determining unit (110) adapted to determine whether the compressor is in a cold state or not; and a rotating speed control unit (120) adapted to control a rotating speed of the motor (30) to increase so that a warm-up operation is executed when the cold state determining unit (110) determines that the compressor is in the cold state.

Description

  The present invention relates to a compressor control device, and more particularly, to a compressor control device capable of warming up by temporarily increasing the rotational speed of a motor.

  Conventionally, as a piston used in a compressor, a locking piston that reciprocates while swinging in a cylinder by a connecting rod connected to a crankshaft is known. In such a locking piston, a lip ring is provided as a seal member at the tip of the piston rod, and the gap between the cylinder and the piston rod is sealed by this lip ring (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 09-068279

  However, since the lip ring as such a seal member undergoes a dimensional change due to thermal expansion, the lip ring also cools and contracts when the compressor is cold, so that sufficient sealing performance cannot be exhibited. For this reason, when the operation stoppage time is long or when it is used in a cold region, the sealing performance of the lip ring is lowered.

  Further, since the lip ring is deformed due to the influence of the compression heat and the pressing load on the cylinder wall, or is worn by continuous use, in such a deformed or worn lip ring, the seal before thermal expansion is used. The decrease in performance is significant.

  If the motor is operated at an increased rotational speed, the amount of frictional heat and compression heat generated increases, so that thermal expansion of the lip ring can be promoted. However, when the rotational speed of the motor is reduced for power saving and noise reduction, there is a problem that the lip ring is not easily heated and thermal expansion does not occur until sufficient sealing performance is exhibited.

  Therefore, the present invention promotes thermal expansion of the lip ring by temporarily increasing the rotational speed even when the rotational speed of the motor is lowered for power saving and noise reduction, and quickly improves the sealing performance and compresses. It is an object to provide a compressor capable of increasing the efficiency.

  The present invention has been made to solve the above-described problems, and is characterized by the following.

(Claim 1)
The invention described in claim 1 is characterized by the following points.

That is, the compressor control device according to claim 1 includes a motor, a piston rod that reciprocates in a cylinder by the motor, and a seal member for sealing between the piston rod and the cylinder. A compressor having two operation modes: a low speed operation mode in which an upper limit of the rotational speed of the motor is set low and a high speed operation mode in which an upper limit of the rotational speed of the motor is set high. A cold state determining means for determining whether or not the engine is in a cold state; and when the compressor is determined to be in a cold state by the cold state determining means, the rotational speed of the motor is increased until a predetermined stop condition is satisfied. and characterized by performing the warm-up operation until a predetermined condition is satisfied and rotational speed control means for controlling to perform the warming up, the disposed, in the low speed operation mode Te That.

(Claim 2)
The invention described in claim 2 has the following features in addition to the features of the invention described in claim 1 described above.

  That is, the cold state determination means determines whether or not the compressor is in a cold state based on whether or not a predetermined time has elapsed since the warm-up operation was executed.

(Claim 3)
The invention described in claim 3 is characterized by the following points in addition to the characteristics of the invention described in claim 1 or 2.

  That is, the cold state determination means determines whether the compressor is in a cold state based on the ambient temperature or the compressor temperature.

(Claim 4)
The invention according to claim 4 is characterized by the following points in addition to the features of the invention according to any one of claims 1 to 3.

  That is, the cold state determination means determines that the compressor is in a cold state when the motor is driven for the first time after power is supplied.

(Claim 5)
The invention according to claim 5 is characterized by the following points in addition to the features of the invention according to any one of claims 1 to 4.

  That is, the cold state determining means determines whether or not the compressor is in a cold state based on the stop time of the motor.

(Claim 6)
The invention described in claim 6 is characterized by the following points in addition to the features of the invention described in any one of claims 1-5.

  That is, the cold state determining means determines whether or not the compressor is in a cold state based on the pressure increase rate over a predetermined time.

(Claim 7)
The invention described in claim 7 is characterized by the following points in addition to the characteristics of the invention described in any one of claims 1-6.

  That is, the cold state determination means determines whether the compressor is in a cold state based on at least one of a current value supplied to the motor, a voltage value supplied to the motor, and a rotation speed of the motor. It is characterized by determining.

(Claim 8)
The invention described in claim 8 is characterized by the following points in addition to the characteristics of the invention described in any one of claims 1-7.

  That is, a switch for switching whether or not to perform the warm-up operation is provided.

  The present invention is as described above, and when it is determined that the compressor is in a cold state, the motor is controlled so as to perform a warm-up operation by increasing the rotation speed of the motor. Even when the rotational speed is decreased, the thermal expansion of the seal member can be promoted by temporarily increasing the rotational speed, and the sealing performance can be quickly improved to increase the compression efficiency. In addition, since the warm-up operation is executed only when the compressor is in a cold state, unnecessary rotation speed is not increased, and the sealing performance can be improved efficiently.

  Further, the cold state determination means may determine whether or not the compressor is in a cold state based on whether or not a predetermined time has elapsed since the warm-up operation was executed. In this way, it is possible to determine the cold state with a simple configuration and to limit the execution time of the warm-up operation.

  The cold state determination means may determine whether or not the compressor is in a cold state based on the ambient temperature or the compressor temperature. In this way, it can be directly determined whether or not the compressor is in a cold state.

  The cold state determination means may determine that the compressor is in a cold state when the motor is driven for the first time after power is supplied. That is, when the power is not supplied, it can be estimated that the operation has been stopped for a certain period of time, and therefore, it may be determined that the compressor is in a cold state.

  The cold state determination means may determine whether or not the compressor is in a cold state based on the stop time of the motor. For example, it is determined whether or not the compressor is in a cold state based on the continuous stop time of the motor, and whether or not the compressor is in a cold state based on a result of a relative comparison between the drive time and the stop time of the motor. It may be judged. In this way, since the cold state can be determined uniformly by measuring the stop time of the motor, it is possible to determine whether the compressor is in the cold state with simple control.

  Further, the cold state determination means may determine whether or not the compressor is in a cold state based on a pressure increase rate in a predetermined time. In this way, since the cold state can be determined based on the compression efficiency of the actual compressor, the warming-up operation can be performed at a timing at which an effect can be directly expected.

  Whether the compressor is in a cold state based on at least one of a current value supplied to the motor, a voltage value supplied to the motor, and a rotation speed of the motor. May be determined. In this way, since it can be determined whether or not it is in a cold state based on the actual compression efficiency and the like, an improvement in sealing performance directly linked to the compression efficiency can be expected.

  Further, a switch for switching whether or not to execute the warm-up operation may be provided. In this way, it is possible to select not to perform the warm-up operation. For example, when it is desired to constantly suppress the generation of noise in an environment such as remodeling, or when it is desired to reduce the amount of current to prevent the breaker from dropping, the warm-up operation can be prevented from being executed.

It is sectional drawing of the locking piston with which a compressor is provided. It is a block diagram which shows the structure of the control apparatus of a compressor. It is a flowchart when a compressor is performed by low-speed operation mode. It is a flowchart which shows the example of 1st cold state determination. It is a flowchart which shows the example of a 2nd cold state determination. It is a flowchart which shows the example of 3rd cold state determination. It is a flowchart when a compressor is performed by high-speed operation mode.

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

  The compressor according to the present embodiment includes a locking piston that houses a piston rod 11 in a cylinder 10, and stores air compressed by the locking piston in a compressed air storage tank (not shown). Compressed air can be supplied to a nailing machine or the like.

  The locking piston is operated by a motor 30 provided inside the compressor. By operating a crank mechanism (not shown) by the motor 30, the piston rod 11 reciprocates in the cylinder 10 and air Is configured to compress.

  As shown in FIG. 1, the piston rod 11 is formed so as to be slidable while oscillating in the cylinder 10, and a dish-like piston portion is formed at the tip portion 13 of the piston rod 11. ing. Further, a crankshaft (not shown) provided in the compressor body is supported in the bearing hole 12 formed at the eccentric position of the base (large end) of the piston rod 11, and this crankshaft is It is operatively connected to a motor 30 provided in the compressor body.

  Therefore, by operating the motor 30, the crankshaft is rotated, thereby causing the base portion of the piston rod 11 to move eccentrically, and the tip portion 13 of the piston rod 11 reciprocates in the sliding direction (direction D1 in FIG. 1). It comes to exercise. That is, the compressor according to the present embodiment reciprocates the piston rod 11 by the rotation of the crankshaft to compress the air taken into the cylinder 10 and send it to various devices and tools that operate with the compressed air. It is like that.

  Incidentally, the piston rod 11 according to the present embodiment is integrally provided with a piston portion as shown in FIG. For this reason, with the reciprocating motion of the piston rod 11 as described above, the tip portion 13 of the piston rod 11 swings in a direction perpendicular to the sliding direction (direction D2 in FIG. 1), and the cylinder 10 and the piston rod 11 A gap will be created between them.

  As shown in FIG. 1, a lip ring 14 as a seal member for sealing between the piston rod 11 and the cylinder 10 is attached to the outer periphery of the tip portion 13 of the piston rod 11. The gap between the cylinder 10 and the piston rod 11 is sealed. For this reason, the gap generated when the tip portion 13 of the piston rod 11 swings is sealed by the lip ring 14 being elastically deformed.

  This lip ring 14 is made of a non-metallic material such as synthetic resin, synthetic rubber or the like, specifically, polytetrafluoroethylene or modified polytetrafluoroethylene, copper or bronze alloy powder, spherical carbon or carbon fiber, or molybdenum dioxide. It is an annular member that is formed and continuous without any breaks. Specifically, the lip ring 14 has a shape in which the lip portion is erected from the entire peripheral edge of the annular plate-shaped bottom portion.

  The lip ring 14 is fixed to the upper surface of the piston rod 11 with a ring presser 15 as shown in FIG. That is, a ring presser 15 is fitted in a recess formed on the upper surface of the piston rod 11, and the ring presser 15 is fixed to the upper surface of the piston rod 11 by a fixing bolt 16 inserted from above. The lip ring 14 is sandwiched and fixed between the ring presser 15 and the piston rod 11.

  Since the lip ring 14 undergoes a dimensional change due to thermal expansion, the lip ring 14 may be cooled and contracted in a state where the compressor is cold, and sufficient sealing performance may not be exhibited. In particular, when the lip ring 14 is worn or deformed due to continuous use or the like, the deterioration of the sealing performance becomes remarkable.

  For this reason, the compressor according to the present embodiment performs a warm-up operation that temporarily increases the rotational speed, thereby increasing the generation amount of frictional heat and compression heat to promote the thermal expansion of the lip ring 14 and quickly seal it. The performance is improved to increase the compression efficiency.

The compressor according to the present embodiment includes a “low speed operation mode” in which the upper limit of the rotation speed of the motor 30 is set low, and a “high speed operation mode” in which the upper limit of the rotation speed of the motor 30 is set high. These operation modes can be switched. Since the problem that the thermal expansion of the lip ring 14 is not promoted mainly occurs in the “low speed operation mode”, in the present embodiment, it is assumed that the warm air operation is executed in the “low speed operation mode”. However, the embodiment of the present invention is not limited to this, and an operation mode other than the “low-speed operation mode” or the “high-speed operation mode” may be provided, and the operation mode for performing the warm-up operation is executed in an arbitrary mode. Can be formed.

  This warm-up operation is controlled by a control device 100 (see FIG. 2) built in the compressor 1, and this control device 100 controls not only the warm-up operation but also the operation of the entire compressor. Is for.

  Although not particularly illustrated, the control device 100 is configured around a CPU and includes a ROM, a RAM, an I / O, and the like. Then, the CPU reads a program stored in the ROM, thereby configuring a cold state determination unit 110 that determines whether or not the compressor is in a cold state and a rotation speed control unit 120 that controls the rotation speed of the motor 30. ing. Control device 100 is not limited to the above-described means, and may include other means.

  Further, as shown in FIG. 2, a temperature sensor 20, a pressure sensor 21, an ammeter 22, a warm-up operation switch 23, and a turbo switch 24 are connected as inputs to the control device 100. .

  Further, as shown in FIG. 2, the motor 30 and the display means 31 are connected as outputs to the control device 100.

  The input / output connected to the control apparatus 100 is not limited to the above, and other devices may be connected. Also, depending on the mode of cold state determination to be described later, input / output that is not used can be omitted.

  Hereinafter, each of the above-described configurations will be described in detail.

  The temperature sensor 20 is for measuring the ambient temperature (or compressor temperature) of the lip ring 14 or the compressor. The temperature measured by the temperature sensor 20 is output to the cold state determination unit 110 based on a signal output from the cold state determination unit 110, and is used for cold state determination described later.

  The pressure sensor 21 is for measuring the pressure in the compressed air storage tank. The pressure measured by the pressure sensor 21 is output to the cold state determination unit 110 based on the signal output from the cold state determination unit 110 and is used for cold state determination described later.

  The ammeter 22 is for measuring the current value supplied to the motor 30. The current value measured by the ammeter 22 is output to the cold state determination unit 110 based on the signal output from the cold state determination unit 110 and used for cold state determination described later.

  The warm-up operation switch 23 is a push switch for executing the warm-up operation. By depressing the warm-up operation switch 23, it is possible to switch whether or not the warm-up operation is executed. In the present embodiment, the warm-up operation switch 23 is used only in the low-speed operation mode.

  The turbo switch 24 is a push switch for further increasing the rotational speed of the motor 30 in the high speed operation mode. By depressing the turbo switch 24, as will be described later, the turbo switch 24 can be operated for a predetermined period in the rotation speed increasing mode, and the output can be further increased in the high speed operation mode.

  The display means 31 performs a display for notifying that the warm-up operation is currently being performed or the rotation speed increase mode is being performed during the warm-up operation and the high-speed operation mode. For example, a lamp may be provided as the display unit 31, and the lamp may be turned on or blinked. In addition to this, 7-segment display or liquid crystal may be provided as the display means 31, and a predetermined display may be performed. Alternatively, a speaker may be provided as the display means 31, and the warm-up operation and the rotation speed increase mode can be discriminated by outputting sound or sound. You may do it.

  The cold state determination means 110 is for determining whether or not the compressor is in a cold state, and is configured as a program for determining whether or not the compressor is in a cold state based on inputs from various sensors. ing. When it is determined by the cold state determining means 110 that the compressor is in a cold state, a signal based on the determination result is output to the rotational speed control means 120 described later, and the rotational speed control means 120 that has received this signal receives the motor. It is formed so that the number of revolutions of 30 is increased and the warm-up operation is executed.

  The rotational speed control means 120 is configured as a program for controlling the rotational speed of the motor 30 and is for rotating the motor 30 at an optimal rotational speed. For example, the rotation speed of the motor 30 is controlled by adjusting the supply voltage to the motor 30 according to the execution mode such as the low speed operation mode and the high speed operation mode. In the present embodiment, as described above, the rotation speed control means 120 is configured to increase the rotation speed of the motor 30 based on the determination result by the cold state determination means 110 and to execute the warm-up operation.

(Explanation of warm-up operation)
Next, the warm-up operation according to the present embodiment will be specifically described.

(Low-speed operation mode execution flow)
Since the warm-up operation according to this embodiment is executed in the low-speed operation mode, first, the execution flow in the low-speed operation mode will be described.

  As shown in FIG. 3, the low-speed operation mode is executed according to the following flow.

  That is, as shown in step 100 of FIG. 3, first, the power switch is turned on and the compressor is started. Then, the process proceeds to step 101.

  In step 101, it is checked whether or not the warm-up operation switch 23 has been pressed. If the warm-up operation switch 23 has not been pressed, the routine proceeds to step 105.

  In step 102, the rotational speed control means 120 controls the rotational speed of the motor 30 to increase, and the warm-up operation is executed. At this time, the display means 31 displays that the warm-up operation is currently being performed (for example, the lamp is lit). Then, the process proceeds to Step 103.

  In step 103, the cold state determination by the cold state determination unit 110 is executed. Details of the cold state determination will be described later. Then, the process proceeds to Step 104.

  In step 104, it is checked whether or not the cold state is determined by the cold state determination means 110, and if it is determined that the state is cold, the process returns to step 102 and warms up until it is determined that the state is not cold. Run the operation. On the other hand, if it is determined not to be in the cold state, the warm-up operation is stopped and the process proceeds to step 105. When the warm-up operation is stopped, the display by the display means 31 is also terminated (for example, the lamp is turned off).

  In step 105, the rotation speed control means 120 controls the rotation speed of the motor 30 so that it becomes a normal rotation speed (the rotation speed specified in the low speed operation mode), and the operation is executed in this state. This operation is executed until it is detected by the pressure sensor 21 that a predetermined stop pressure has been reached. When it is detected that a predetermined stop pressure has been reached, it is determined that a sufficient amount of air has been compressed in the compressed air storage tank, and the operation of the motor 30 is stopped. Then, the process proceeds to Step 106.

  In step 106, it is checked whether the pressure in the compressed air storage tank has decreased due to the use of the compressed air in the compressed air storage tank by the nail driver or the like. If the re-operation pressure has been reached due to the pressure drop in the compressed air storage tank, the routine proceeds to step 107. On the other hand, if the re-operation pressure has not been reached, the system waits until the re-operation pressure is reached.

  In step 107, it is checked whether the operation has been stopped for a predetermined time (for example, 45 minutes). If the operation has been stopped for a predetermined time or longer, the process proceeds to step 108. On the other hand, if the operation has not stopped for a predetermined time or longer, the process proceeds to step 105, and the operation is performed at the normal rotation speed (the rotation speed specified in the low speed operation mode).

  In step 108, it is checked whether or not the warm-up operation switch 23 has been pressed. If it has been pressed, the routine proceeds to step 108, where the cold state determination is executed. On the other hand, if the warm-up operation switch 23 has not been pressed, the routine proceeds to step 105, where the operation is executed at the normal rotation speed (the rotation speed specified in the low-speed operation mode).

(Cool state determination flow)
Next, the flow of cold state determination according to the present embodiment will be described with reference to FIGS. In addition, the following cold state determination is only an example, and any of the following cold state determinations may be used or may be used in combination. Also, some processes may be omitted or replaced.

(First cold state determination flow)
FIG. 4 is a diagram showing a first cold state determination flow. In this cold state determination, the cold state determination means 110 determines whether or not the compressor is in a cold state based on whether or not a certain time has elapsed since the warm-up operation was executed.

  That is, as shown in step 200 of FIG. 4, by measuring the time since the previous operation (normal operation or warm-up operation) was completed, and checking whether the measured value is equal to or greater than a predetermined value, Check if a certain time has passed since the operation was executed. If the predetermined time has elapsed, the process proceeds to step 202, where it is determined that it is not in the cold state, and the cold state determination process ends. On the other hand, if the predetermined time has not elapsed, the process proceeds to step 201, where the cold state is determined, and the cold state determination process ends.

  According to such a cold state determination flow, it is possible to uniformly determine the cold state without performing complicated processing, and it is also possible to limit the execution time of the warm-up operation.

(Second cold state determination flow)
FIG. 5 is a diagram showing a second cold state determination flow. In this cold state determination, the cold state determination means 110 is supplied to the ambient temperature or the compressor temperature, the pressure increase rate in a certain time, the current value (secondary current value) supplied to the motor 30, and the compressor conset. Whether or not the compressor is in a cold state is determined based on the current value (primary current value) and the rotation speed of the motor 30.

  That is, as shown in step 300 of FIG. 5, first, the temperature sensor 20 measures the ambient temperature (or compressor temperature) of the lip ring 14 and the compressor, and checks whether the temperature is below a certain level. To do. And when temperature is below fixed, it progresses to step 305, it determines with a cold state, and a cold state determination process is complete | finished. On the other hand, if the temperature is not below a certain level, the process proceeds to step 301.

  In step 301, it is checked using the pressure sensor 21 whether or not the pressure in the compressed air storage tank has dropped. If the pressure is increasing, go to step 302. On the other hand, if the pressure is not increasing, the process proceeds to step 303.

  In step 302, the rate of increase in pressure per hour is calculated based on the pressure change measured by the pressure sensor 21, and it is checked whether the rate of increase in pressure is below a threshold value. That is, it is checked whether air leaks from the lip ring 14 by checking whether the pressure in the compressed air storage tank is rising efficiently. As a result of this check, if the pressure increase rate is equal to or less than the threshold value, the process proceeds to step 305, where it is determined that the temperature is cold, and the cold state determination process ends. On the other hand, when the pressure increase rate is not less than or equal to the threshold value, the process proceeds to step 304, where it is determined that the pressure state is not cold, and the cold state determination process ends.

  In step 303, it is checked whether the current value supplied to the motor 30 is equal to or smaller than the threshold value, or whether the rotation speed of the motor 30 is equal to or larger than the threshold value. That is, when air is leaking from the lip ring 14, the load of the compressor is reduced, and the current value supplied to the motor 30 is reduced. Therefore, the current value supplied to the motor 30 using the ammeter 22. It is possible to check whether air is leaking from the lip ring 14 by checking whether or not the current value is equal to or less than the threshold value. In addition, when air leaks from the lip ring 14, the compression efficiency of the compressor is lowered, and processing for increasing the rotation speed of the motor 30 is performed to compensate for this, so that the rotation speed of the motor 30 exceeds the threshold value. Whether or not air is leaking from the lip ring 14 can also be checked.

  In addition, by checking the current value and the rotation speed together, when operating with the rotation speed of the motor 30 being limited, it is possible to check for air leakage by checking the current value and to limit the current value. When operating, the air leakage can be checked by checking the rotation speed of the motor 30.

  If the current value is equal to or less than the threshold value or the rotation speed is equal to or greater than the threshold value, the process proceeds to step 305, where the cold state is determined, and the cold state determination process ends. On the other hand, if the current value is not less than or equal to the threshold value and the rotation speed is not greater than or equal to the threshold value, the process proceeds to step 304, where it is determined that the current state is not cold, and the cold state determination process ends.

  According to such a cold state determination flow, since it is determined whether or not it is in a cold state mainly by checking the compression efficiency, an improvement in compression efficiency can be expected directly by the warm-up operation.

  In the above description, the current value supplied to the motor 30 is checked. However, the current value supplied to the compressor conset or the voltage value may be checked instead of the current value.

(Third cold state determination flow)
FIG. 6 is a diagram showing a third cold state determination flow. In this cold state determination, it is determined whether or not the motor 30 is first driven after power is supplied, and whether or not the compressor is in a cold state based on the stop time of the motor 30 or the like.

  That is, as shown in step 400 of FIG. 6, it is checked whether or not the motor 30 is first driven after the power is supplied. Here, when the motor 30 is driven for the first time after the power is supplied, it can be estimated that the compressor is cold. Therefore, the process proceeds to step 404, where the cold state is determined and the cold state determination process ends. . On the other hand, if the motor 30 is not driven for the first time after the power is supplied, the process proceeds to step 401.

  In step 401, it is checked whether the operation has been stopped for a certain period of time and the motor 30 has not been rotated. If the operation has been stopped for a certain time or longer, it can be estimated that the compressor is cold. Therefore, the process proceeds to step 404, where the cold state is determined and the cold state determination process ends. On the other hand, if the operation has not stopped for a certain time or longer, the process proceeds to step 402.

  In step 402, the relative ratio between the operation time and the stop time is checked, and it is determined whether the ratio of the stop time is equal to or greater than a certain ratio. If the ratio of the stop time is equal to or greater than a certain ratio, it can be estimated that the compressor is cold because the stop time is long. Therefore, the process proceeds to step 404 where it is determined that the compressor is cold and the cold state determination process is performed. finish. On the other hand, if the ratio of the stop time is not equal to or greater than the predetermined ratio, the process proceeds to step 403, where it is determined that the cold state is not present, and the cold state determination process is terminated.

  According to such a cold state determination flow, since the cold state is determined based on the operation state of the motor 30, it is possible to easily determine the cold state.

(Explanation of high-speed operation mode)
Next, the high speed operation mode will be described.

  In the present embodiment, in addition to the above-described warm-up operation, a rotation speed increase mode for temporarily increasing the rotation speed of the motor 30 is provided. This rotation speed increase mode can be executed in the high-speed operation mode in the present embodiment.

  That is, as shown in step 500 of FIG. 7, first, the power switch is turned on and the compressor is started. Then, the process proceeds to step 501.

  In step 501, it is checked whether or not the turbo switch 24 has been pressed. If the turbo switch 24 has not been pressed, the process proceeds to step 504.

  In step 502, it is checked whether or not the rotation of the motor 30 has been stopped for a certain period of time. If the motor 30 has been stopped for a certain period or more, the process proceeds to step 503. On the other hand, if the motor 30 has not stopped for a certain time or longer, it is presumed that the motor 30 is at a high temperature.

  In step 503, the engine speed increases mode is entered until a predetermined time elapses. That is, the rotation speed control means 120 controls to increase the rotation speed of the motor 30. At this time, the display means 31 starts displaying at the start of the rotation speed increase mode (for example, the lamp is turned on) and displays that the current rotation speed increase mode is in effect until the rotation speed increase mode ends. Then, the process proceeds to step 504.

  In step 504, the rotational speed of the motor 30 is controlled so as to be the normal rotational speed (the rotational speed specified in the high speed operation mode), and the operation is executed in this state. Then, the process proceeds to step 501.

  Although not described in the above flow in order to simplify the description, it goes without saying that the operation of the motor 30 is controlled in accordance with the pressure change in the compressed air storage tank, as in the flow in FIG. .

  As described above, according to the present embodiment, the compression efficiency can be temporarily improved by executing the rotation speed increase mode even when the warm-up operation is not required.

(Summary)
As described above, according to the present embodiment, when it is determined that the compressor is in the cold state, control is performed so as to perform the warm-up operation by increasing the rotation speed of the motor 30. Therefore, even when the rotational speed of the motor 30 is reduced, the thermal expansion of the lip ring 14 can be promoted by temporarily increasing the rotational speed, and the sealing performance can be quickly improved to increase the compression efficiency. In addition, since the warm-up operation is executed only when the compressor is in a cold state, unnecessary rotation speed is not increased, and the sealing performance can be improved efficiently.

  Further, since the warm-up operation is performed when the warm-up operation switch 23 is pressed, it is possible to select not to perform the warm-up operation unless the warm-up operation switch 23 is pressed. For this reason, for example, when it is desired to always suppress the generation of noise in an environment such as remodeling, or when it is desired to reduce the amount of current to prevent the breaker from dropping, it is possible to prevent the warm-up operation from being executed.

  In the above description, the warm-up operation is performed when the warm-up operation switch 23 is pressed in the low-speed operation mode. However, the present invention is not limited to this, and the warm-up operation is always performed when it is determined to be in the cold state. It may be formed.

DESCRIPTION OF SYMBOLS 10 Cylinder 11 Piston rod 12 Bearing hole 13 Tip part 14 Lip ring (seal member)
DESCRIPTION OF SYMBOLS 15 Ring clamp 16 Fixing bolt 20 Temperature sensor 21 Pressure sensor 22 Ammeter 23 Warm-up operation switch 24 Turbo switch 30 Motor 31 Display means 100 Control apparatus 110 Cold state determination means 120 Rotation speed control means D1 Piston rod sliding direction D2 Piston Rod swing direction

Claims (8)

A motor,
A piston rod that reciprocates in the cylinder by the motor;
A sealing member for sealing between the piston rod and the cylinder;
Equipped with a,
In the compressor having two operation modes, a low speed operation mode in which the upper limit of the rotation speed of the motor is set low and a high speed operation mode in which the upper limit of the rotation speed of the motor is set high .
Cold state determining means for determining whether or not the compressor is in a cold state;
A rotational speed control means for controlling to increase the rotational speed of the motor and perform a warm-up operation when it is determined by the cold state determination means that the compressor is in a cold state;
Provided ,
A control device for a compressor , wherein a warm-up operation is executed until a predetermined condition is satisfied in the low-speed operation mode .   2. The compressor according to claim 1, wherein the cold state determination unit determines whether or not the compressor is in a cold state based on whether or not a predetermined time has elapsed since the warm-up operation was performed. Control device.   The compressor control device according to claim 1 or 2, wherein the cold state determination means determines whether or not the compressor is in a cold state based on an ambient temperature or a compressor temperature.   The compression according to any one of claims 1 to 3, wherein the cold state determination means determines that the compressor is in a cold state when the motor is driven for the first time after power is supplied. Machine control device.   The compressor control device according to any one of claims 1 to 4, wherein the cold state determination means determines whether or not the compressor is in a cold state based on a stop time of the motor.   The control device for a compressor according to any one of claims 1 to 5, wherein the cold state determination means determines whether or not the compressor is in a cold state based on a pressure increase rate in a predetermined time. .   The cold state determining means determines whether or not the compressor is in a cold state based on at least one of a current value supplied to the motor, a voltage value supplied to the motor, and a rotation speed of the motor. The compressor control device according to claim 1, wherein the control device is a compressor. The control device for a compressor according to any one of claims 1 to 7, further comprising a switch for switching whether or not to perform the warm-up operation.

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