JP6618426B2 - Air pump idle detection device - Google Patents

Description

  The present invention relates to an air pump idle detection device.

  Patent Document 1 discloses a device that detects an idling of a pump. The pump is provided with a weir in the liquid flow path, and in a state where the liquid is being pumped, the valve body made of a magnetic material is moved away from the weir by the pressure of the flowing liquid. Further, in the idle driving state in which the liquid pumping is stopped, the valve body is kept in contact with the weir by the return spring. The idling detection device includes a magnetic sensor that detects whether or not the valve body is in contact with the weir based on a change in the magnetic field, and a control device that is electrically connected to the magnetic sensor. The control device detects the occurrence of idling based on the change in the magnetic field detected by the magnetic sensor.

Japanese Patent Application Laid-Open No. 08-144962

  Since the above-described idling detection device uses electric devices such as a magnetic sensor and a control device, an explosion-proof facility is required when applied to a pump for electrostatic coating, resulting in high costs. Further, it cannot be used in an environment where power supply facilities are not prepared.

  The present invention has been completed based on the above-described circumstances, and an object of the present invention is to detect air pump idle driving without using an electric device.

The present invention
An idle driving detection device for detecting an empty shot of an air pump in which a piston is driven by air supplied from an air pressure supply source and stroke-linked pilot air is supplied for each stroke of the piston using the air pressure supply source as a supply source. There,
Measurement of one-stroke required time of the piston is started by the supply of the stroke-linked pilot air, and the air pressure supply source is used as a supply source until the measured value of the required one-stroke time of the piston reaches a measurement threshold. Measuring means for sending out the integrating pilot air and stopping the sending out of the integrating pilot air when the measured value of the time required for one stroke of the piston exceeds the measuring threshold;
While the integration pilot air is being supplied, the time required for one stroke of the piston is integrated, and the air pressure supply source is supplied only when the load value for the time required for one stroke of the piston reaches the determination threshold. It has a feature in that it comprises a determination means for sending out the air blow determination air as a source.

  When the air pump is not idle, the time required for one piston stroke is longer than the measurement threshold value, and the sending of the pilot air for integration stops before the end of one piston stroke. End before reaching the threshold. When the air pump is idle, the time required for one stroke of the piston becomes shorter than the threshold for measurement, and the next stroke starts before the transmission of the pilot air for integration stops. The data is continuously sent out, and the determination unit continues the integration. Then, when the integrated value reaches the determination threshold value, idle determination air is sent out, and it is detected that the air pump is in an idle state. According to the present invention, it is possible to detect the idling of the air pump without using an electric device.

Pneumatic circuit diagram showing a state in which the on-delay timer for measuring the upward stroke and the integration of the on-delay timer for integrating are performed during the upward stroke of the piston of the air pump in the first embodiment. Pneumatic circuit diagram showing the state where the on-delay timer for ascending stroke measurement and the loading of the on-delay timer for accumulation are stopped during the ascending stroke of the piston Pneumatic circuit diagram showing the state where the on-delay timer for the downward stroke measurement and the integration of the on-delay timer for the integration are performed during the downward stroke of the piston Pneumatic circuit diagram showing a state where the integrated value of the integration on-delay timer has reached the determination threshold, the determination air is sent, and the supply of air from the air pressure supply source to the air pump is stopped Time chart showing the operation of the measurement on-delay timer and integration on-delay timer in the process from the normal operation of the air pump to the idle driving state

In the present invention, the measuring means comprises:
An integration operation control switching valve that switches to a state in which the integration pilot air can be sent out by supplying the stroke-linked pilot air;
A measurement on-delay timer that starts measuring the time required for one stroke of the piston by supplying the stroke-linked pilot air, and when the measurement value of the measurement on-delay timer reaches the measurement threshold, the air pressure supply source And a measurement delay release valve for sending the integration stop pilot air using the supply source to switch the integration operation control switching valve to the delivery stop state of the integration pilot air.
According to this configuration, when the air pump is not idle, the measurement value of the measurement on-delay timer reaches the measurement threshold before the end of one stroke of the piston, and the integration delay is stopped from the measurement delay release valve. Since pilot air is sent out, the integrated operation control switching valve stops sending out the integrated pilot air. When the air pump is idle, the state in which the integration stop pilot air is not sent from the measurement delay release valve continues, so that the integration pilot air continues to be sent to the determination means.

  In the present invention, the determination unit includes an integration on-delay timer that integrates the time required for one stroke of the piston by supplying the integration pilot air, and the integrated value of the integration on-delay timer is set as the determination threshold value. When it reaches, it may be provided with a determination delay release valve for sending the idle determination air.

  According to this configuration, in the state where the air pump is not idle, the supply of the integration pilot air is stopped before the end of one piston stroke. Accumulation ends before reaching. When the air pump is idle, the integration pilot air continues to be sent, so the integration on-delay timer continues to integrate. When the integrated value of the on-delay timer for integration reaches the determination threshold, the determination delay release valve sends out the empty determination air.

The present invention may include a pump control switching valve that switches a pump driving switching valve for supplying air from the air pressure supply source to the air pump by the supply of the idle driving determination air.
According to this configuration, when the idle driving determination air is detected and the idle driving determination air is sent, the pump drive switching valve is closed and the supply of air to the air pump is stopped. It is possible to prevent the hit state from continuing.

<Example 1>
A first embodiment of the present invention will be described below with reference to FIGS. The detection target of the idle detection device 20 of the present embodiment is an air pump 12 that discharges a liquid such as paint by the pressure of air that is pumped from the air pressure source 10 through the pump driving air flow path 11. The pump drive air flow path 11 is provided with a normally closed pump drive switching valve 14. The pump drive switching valve 14 is opened when the pump drive pilot air is supplied.

<Air pump 12>
The air pump 12 has a piston 13 that moves up and down by air pumped from the air pressure source 10, and is a reciprocating pump that discharges liquid in both the upward stroke and the downward stroke of the piston 13. In the present embodiment, the upward stroke from the bottom dead center to the top dead center of the piston 13 and the downward stroke from the top dead center to the bottom dead center of the piston 13 are each defined as one stroke.

  While the piston 13 is performing a one-stroke ascending stroke, the air pump 12 sends up-stroke-stroke-linked pilot air using the air pressure supply source 10 as a supply source. While the piston 13 is performing a one-stroke downward stroke, the air pump 12 sends downward stroke stroke-linked pilot air using the air pressure supply source 10 as a supply source. Further, in this embodiment, both the time required for one stroke when the piston 13 rises while normally discharging the liquid and the time required for one stroke when the piston 13 descends while normally discharging the liquid are 2. The time is longer than 0 seconds.

<Improvement detection device 20>
Next, the idling detection device 20 will be described. The air blow detection device 20 includes pump control means 22 for controlling the supply of air from the air pressure supply source 10 to the air pump 12, and air blow detection means 27 for detecting air blow of the air pump 12. . The pump control means 22 and the idle driving detection means 27 are accommodated in a common housing 21.

<Pump control means 22>
The pump control means 22 includes a pump control pilot air passage 23 and a pump control switching valve 24 provided in the middle of the pump control pilot air passage 23. The upstream end of the pump control pilot air flow path 23 is connected to the air pressure supply source 10, and the downstream end of the pump control pilot air flow path 23 is connected to the pilot port of the pump drive switching valve 14. Connected.

  In a state in which the air pump 12 is operating normally without being idle, the pilot air for pump control using the air pressure source 10 as the supply source passes through the pump control switching valve 24 and the pilot of the pump driving switching valve 14. Since it is supplied to the port, the pump drive switching valve 14 is opened, and air is supplied from the air pressure source 10 to the air pump 12. Further, when the air pump 12 is in an idle state, the pump control switching valve 24 is switched to an exhaust state by supply of an idle determination air to be described later. As a result, the supply of pump control pilot air to the pump drive switching valve 14 is not performed, so that the pump drive switching valve 14 is closed.

  The pump control means 22 includes a reset pilot air passage 25 and a normally closed reset switching valve 26 provided in the middle of the reset pilot air passage 25. When the reset switching valve 26 is switched to the open state before the air pump 12 is driven, reset pilot air using the air pressure supply source 10 as a supply source is supplied to the pilot port of the pump control switching valve 24, and the pump control switching is performed. The valve 24 is in a state of supplying pilot control pilot air to the pilot port of the pump drive switching valve 14. While the air pump 12 is normally driven, the reset switching valve 26 is returned to the closed state.

  In addition, when the pump control switching valve 24 is in an exhaust state due to the idling determination air, the reset pilot air is switched to the pilot port of the pump control switching valve 24 when the reset switching valve 26 is switched to the open state. Since it is supplied, the pump control switching valve 24 switches to a state in which the pump control pilot air is supplied to the pump drive switching valve 14.

<Improvement detection means 27>
The idle shot detection means 27 includes a measurement means 30 and a determination means 50. The idle driving detection unit 27 detects that the air pump 12 is in an idle driving state using air supplied from the air pressure supply source 10. When the idling state is detected, idling determination air is sent from the idling detection means 27 to the pilot port of the pump control switching valve 24.

<Measuring means 30>
The measurement means 30 includes an air-flow detection flow path 31, an ascending process measurement delay release valve 33 (measurement delay release valve), and a descending stroke measurement delay release valve 34 (described in claims). Measurement delay release valve), integration pilot air flow path 35, first integration operation control switching valve 36 (accumulation operation control switching valve described in claims), and second integration operation control switching valve. 37 (a switching valve for integrated operation control described in claims), an ascending stroke stroke interlocking pilot air flow path 40, and a descending stroke stroke interlocking pilot air flow path 41.

  The upstream end of the air blow detection air flow path 31 is connected to the air pressure source 10. The idle driving detection air channel 31 is provided with a main switching valve 32 that functions as a main switch for opening and closing the idle driving detection air channel 31. The downstream end of the air detection detection air flow path 31 is branched into three, and two of the three branch paths are the inlet of the ascending process measurement delay release valve 33 and the delay opening of the descending stroke measurement. It is connected to the inlet of the valve 34. The integrating pilot air flow path 35 is branched from a position downstream of the main switching valve 32 in the idle driving detection air flow path 31. A first integration operation control switching valve 36 and a second integration operation control switching valve 37 are provided in the integration pilot air flow path 35.

  The upstream end of the second integration stop pilot air passage 38 is connected to the outlet of the ascent process measurement delay release valve 33, and the downstream end of the second integration stop pilot air passage 38 is connected to the second integration operation control. The switching valve 37 is connected to one pilot port. A first cumulative stop pilot air flow path 39 is connected to the outlet of the downward stroke measuring delay release valve 34, and the downstream end of the first total stop pilot air flow path 39 is a first cumulative operation control switching valve 36. Is connected to one of the pilot ports.

  The upstream end of the ascending stroke associated pilot air passage 40 is connected to the ascending stroke port 15 of the air pump 12 that sends the ascending stroke associated pilot air in the ascending stroke of the piston 13. The ascending stroke internal pilot air passage 40 is bifurcated on the downstream side, and the downstream end of one of the branch passages is connected to the pilot port of the ascending process measurement delay release valve 33, and the other branch passage is the first branch passage. It is connected to the other pilot port of the integration operation control switching valve 36.

  The upstream end of the descending stroke stroke interlocking pilot air flow path 41 is connected to the descending stroke port 16 of the air pump 12 that sends the descending stroke stroke interlocking pilot air in the descending stroke of the piston 13. The down stroke stroke interlocking pilot air passage 41 is also bifurcated on the downstream side, the downstream end of one branch passage is connected to the pilot port of the delay release valve 34 for the down stroke measurement, and the other branch passage is the second branch passage. This is connected to the other pilot port of the switching valve 37 for integration operation control.

  The ascending process measuring delay release valve 33 is configured to start measuring the time required for one stroke of the ascending stroke of the piston 13 by the supply of the ascending stroke associated pilot air. On-delay timer). In the upward stroke measurement on-delay timer 42, a time shorter than the time required for one stroke of the normal upward stroke of the piston 13 (2.0 seconds in this embodiment) is set as a measurement threshold.

  When the measured value of the upward stroke measuring on-delay timer 42 reaches the measurement threshold value, the ascending process measuring delay release valve 33 uses the air supplied through the idle flow detection air flow path 31 to remove the accumulated stop pilot. It is sent out as air and supplied to one pilot port of the second integrated operation control switching valve 37. The second integration operation control switching valve 37 supplied with the integration stop pilot air is switched to a state in which the integration pilot air flow path 35 is shut off and the transmission of the integration pilot air is stopped. In the state where the measured value of the upward stroke measurement on-delay timer 42 does not reach the measurement threshold, the upward stroke measurement delay release valve 33 does not send out the pilot air for accumulation stop. When the integrated value of the upward stroke measurement on-delay timer 42 reaches the measurement threshold value, the measurement operation is stopped and the measurement value is reset.

  The descending stroke measuring delay release valve 34 is a descending stroke measuring on-delay timer 43 which starts measuring the time required for one stroke of the descending stroke of the piston 13 by the supply of the descending stroke stroke interlocking pilot air (measurement according to claim). On-delay timer). In the down stroke measurement on-delay timer 43, a time shorter than the time required for one stroke of the normal downward stroke of the piston 13 (2.0 seconds in this embodiment) is set as a measurement threshold.

  When the measured value of the down stroke measuring on-delay timer 43 reaches the measurement threshold value, the descending stroke measuring delay release valve 34 uses the air supplied through the idle stroke detection air flow path 31 to pilot the stop for accumulation. It is sent out as air and supplied to one pilot port of the first integrated operation control switching valve 36. The first integration operation control switching valve 36 to which the integration stop pilot air is supplied is switched to a state in which the integration pilot air flow path 35 is shut off and the transmission of the integration pilot air is stopped. When the measured value of the down stroke measuring on-delay timer 43 does not reach the measuring threshold, the descending stroke measuring delay release valve 34 does not send out pilot stop pilot air. When the integrated value of the down stroke measurement on-delay timer 43 reaches the measurement threshold, the measurement operation is stopped and the measurement value is reset.

<Determination means 50>
The determination unit 50 includes a determination delay release valve 51 and an empty shot determination air flow path 52. The remaining one of the three branch paths at the downstream end of the idle flow detection air path 31 is connected to the inlet of the determination delay release valve 51. The upstream end of the idling determination air flow path 52 is connected to the outlet of the determination delay release valve 51. The pilot port of the determination delay release valve 51 is connected to the downstream end of the integrating pilot air flow path 35.

The determination delay release valve 51 includes an integration on-delay timer 53 that integrates the time required for one stroke during the upward stroke and the downward stroke of the piston 13 while the cumulative pilot air is being supplied. In the integration on-delay timer 53, a time twice as long as the measurement threshold (4.0 seconds in this embodiment) is set as the determination threshold.
When the integrated value of the integration on-delay timer 53 reaches the determination threshold value, the determination delay release valve 51 sends out the air supplied through the idle driving detection air flow path 31 as the idle driving determination air pump. This is supplied to the pilot port of the control switching valve 24. When the idle determination air is supplied, the pump control switching valve 24 is switched to the exhaust state, so that the supply of pump control pilot air to the pump driving switching valve 14 is stopped and the pump driving switching valve 14 is closed. The air supply to the air pump 12 is stopped. In the state where the integrated value of the integration on-delay timer 53 does not reach the determination threshold value, the idle shot determination air is not sent. When the integration value of the integration on-delay timer 53 reaches the determination threshold value, the integration operation is stopped and the integration value is reset.

<Operation of Example 1>
Next, the process of detecting that the air pump 12 has been idle is described with reference to the time chart shown in FIG. When air is supplied to the air pump 12, the piston 13 starts to move up and down, and liquid is discharged. In a state where the liquid is normally discharged, the resistance caused by the viscosity of the liquid acts on the piston 13, and therefore the time required for one stroke of the upward stroke and the downward stroke of the piston 13 is longer than 2.0 seconds.

  When the air pump 12 is normally driven and the piston 13 starts to rise (step A), the upward stroke measuring on-delay timer 42 starts measurement by supplying the upward stroke stroke-linked pilot air. Similarly, from the state in which the first integration operation control switching valve 36 blocks the transmission of the integration pilot air to the determination delay release valve 51 by the supply of the upward stroke stroke interlocking pilot air, as shown in FIG. The state is switched to the state where the integrating pilot air is sent to the determination delay release valve 51. The second integration operation control switching valve 37 remains in a state in which the integration pilot air is sent out.

  When the integration pilot air is supplied to the determination delay release valve 51, the integration operation of the determination on-delay timer starts. That is, the measurement of the upward stroke measuring on-delay timer 42 and the integrating operation of the integrating on-delay timer 53 are started almost simultaneously. When the air pump 12 operates normally and the piston 13 continues the ascending stroke, when 2.0 seconds (measurement threshold value) has elapsed from the start of measurement and the process shifts from the A process to the B process, the ascending stroke measuring ON At the same time as the delay timer 42 finishes the measurement, the ascending process measurement delay release valve 33 sends out the pilot air for the accumulation stop.

  When the integration stop pilot air is delivered, as shown in FIG. 2, the second integration operation control switching valve 37 is switched to a state in which the delivery of the integration pilot air is stopped. The pilot air supply for integration stops. Thereby, the on-delay timer for integration 53 ends the integration. Since the integrated value (2.0 seconds) at this time is shorter than the threshold for determination, no idle determination air is sent out.

  When the piston 13 switches from the ascending stroke to the descending stroke and shifts to the C process, the descending stroke measuring on-delay timer 43 starts measuring by supplying the descending stroke stroke interlocking pilot air, and at the same time, as shown in FIG. 2. The switching valve 37 for integrating operation control is switched to a state in which integrating pilot air is sent to the delay opening valve 51 for determination. As a result, the integration pilot air is supplied to the determination delay release valve 51, and the integration operation of the integration on-delay timer 53 starts.

  When the air pump 12 operates normally and the piston 13 continues the downward stroke, when 2.0 seconds (measurement threshold) has elapsed from the start of measurement and the process shifts from the C process to the D process, the downward stroke measurement is turned on. At the same time as the delay timer 43 ends the measurement, the descending stroke measurement delay release valve 34 sends out pilot air for integration stop.

  When the integration stop pilot air is delivered, as shown in FIG. 3, the first integration operation control switching valve 36 is switched to a state in which the delivery of the integration pilot air is stopped. The pilot air supply for integration stops. Thereby, the on-delay timer for integration 53 ends the integration. Since the integrated value (2.0 seconds) at this time is shorter than the threshold for determination, no idle determination air is sent out.

  Thereafter, when the normal operation of the air pump 12 is continued and the process moves from the D process to the F process through the E process, the measuring means 30 performs the same operations as the A process and the B process in the E process and the F process. When the piston 13 is switched to the downward stroke and shifts from the F process to the G process, the initial stage of the G process is the same as the C process, and the downward stroke measuring on-delay timer 43 is used for measurement and integration by supplying the downward stroke stroke-linked pilot air. The integration operation of the on-delay timer 53 starts.

  In this G process, the downward stroke of the piston 13 is completed in a time (1.4 seconds) shorter than the measurement threshold due to some circumstances. Therefore, the piston 13 is switched to the ascending stroke without sending out the total stop pilot air from the descending stroke measuring delay release valve 34. Therefore, the first integration operation control switching valve 36 and the second integration operation control switching valve 37 do not perform the switching operation, and as shown in FIG. 1, the determination delay release valve 51 is supplied with integration pilot air. The state continues. As a result, even if the piston 13 is switched to the upward stroke, the on-delay timer 53 for integration continues the integration operation.

  In this ascending stroke, the piston 13 operates normally. Therefore, before the ascending stroke ends, the measured value of the ascending stroke measuring on-delay timer 42 reaches the measurement threshold value. Accordingly, the pilot air for integration stop is sent from the delay release valve 33 for measuring the ascending process, so that the integration operation of the on-delay timer 53 for integration ends as shown in FIG. 2, and the process proceeds from the G process to the H process. To do. In the H process, the measuring means 30 performs the same operation as the B process and the F process.

  Thereafter, when the piston 13 is switched from the normal ascending stroke to the descending stroke, the process proceeds from the H process to the I process, and when the piston 13 is normally moved down, the process proceeds from the I process to the J process. In the I process and the J process, the measuring means 30 performs the same operation as the C process and the D process. In the step J, as shown in FIG. 3, the first on-time timer 53 for integration is not integrated because the first integration operation control switching valve 36 is switched to a state in which the transmission of the integration pilot air is stopped.

  In this embodiment, immediately after the J process ends and the process shifts to the K process, an idle strike occurs in the upward stroke of the piston 13, and the upward stroke ends in a time shorter than the measurement threshold (1.4 seconds). Yes. Therefore, the piston 13 is switched to the lowering stroke without sending the integration stop pilot air from the ascent process measuring delay release valve 33. Therefore, the first integration operation control switching valve 36 and the second integration operation control switching valve 37 do not perform the switching operation, and as shown in FIG. 1, the determination delay release valve 51 is supplied with integration pilot air. The state continues. Therefore, even if the piston 13 is switched to the upward stroke, the integration on-delay timer 53 continues the integration operation.

  Thereafter, the ascending stroke is switched to the descending stroke. However, in the idling state, the descending stroke is completed in a time (0.9 seconds) shorter than the measurement threshold value. Air is not sent out. Therefore, the piston 13 is switched to the ascending stroke while the integration of the integration on-delay timer 53 continues. Since the subsequent upward stroke also ends in a time shorter than the measurement threshold (0.8 seconds), the downward stroke is switched while the integration of the integration on-delay timer 53 continues.

  When the descent process starts and a time (0.9 seconds) shorter than the measurement threshold elapses, the integrated value of the integration on-delay timer 53 reaches the determination threshold (4.0 seconds). Then, as shown in FIG. 4, the idle determination air is sent from the determination delay release valve 51 to the pump control switching valve 24. As a result, the pump drive switching valve 14 is closed, the supply of air to the air pump 12 is stopped, and the elevation of the piston 13 is also stopped.

  The blank shot detection device 20 of the present embodiment is intended to detect blank shot of the air pump 12 without using an electric device. The detection target of the idle driving device 20 is that the piston 13 is driven by the air supplied from the air pressure supply source 10, and stroke-linked pilot air using the air pressure supply source 10 as a supply source is sent for each stroke of the piston 13. An air pump 12 is provided.

  The empty shot detection device 20 includes a measurement unit 30 and a determination unit 50. The measuring means 30 starts measuring the time required for one stroke of the piston 13 by supplying the stroke-linked pilot air. Until the measured value of the time required for one stroke of the piston 13 reaches the measurement threshold value, the measuring means 30 sends the integrating pilot air using the air pressure supply source 10 as the supply source to the determination means 50. When the measured value of the time required for one stroke of the piston 13 exceeds the measurement threshold value, the measuring means 30 stops sending the integrating pilot air.

  Further, the determination means 50 integrates the time required for one stroke of the piston 13 while the integrating pilot air is supplied. Then, only when the load value of the time required for one stroke of the piston 13 reaches the determination threshold value, the idle determination air using the air pressure supply source 10 as a supply source is sent out.

  In a state where the air pump 12 is not idle, the time required for one stroke of the piston 13 is longer than the measurement threshold value, and the sending of the pilot air for integration stops before the end of one stroke of the piston 13. The integration at is also terminated before the determination threshold is reached.

  When the air pump 12 is idle, the time required for one stroke of the piston 13 becomes shorter than the threshold for measurement, and the next stroke starts before the integration pilot air is stopped. The information is continuously sent to the means 50, and the determination means 50 continues the integration. When the integrated value reaches the determination threshold value, the idle determination air is sent out, and it is detected that the air pump 12 is in the idle state. According to the idling detection device 20 of the present embodiment, it is possible to detect idling of the air pump 12 without using an electric device.

  Further, the measuring means 30 includes a first integration operation control switching valve 36 that switches to a state in which the integration pilot air can be sent out by the supply of the upward stroke stroke-linked pilot air, and the integration pilot by the supply of the downward stroke stroke-linked pilot air. A switching valve 37 for controlling the second integrated operation that switches to a state in which air can be sent is provided. Similarly, the measuring means 30 includes an ascending process measuring delay release valve 33 including an ascending stroke measuring on-delay timer 42 and a descending stroke measuring delay releasing valve 34 including a descending stroke measuring on-delay timer 43.

  The upward stroke measuring on-delay timer 42 starts measuring the time required for one stroke of the piston 13 by the supply of the upward stroke stroke-linked pilot air. When the measured value of the upward stroke measuring on-delay timer 42 reaches the measurement threshold value, the integration stop pilot air with the air pressure supply source 10 as the supply source is sent out, and the second integration operation control switching valve 37 is integrated. Switch to the pilot air delivery stop state.

  The down stroke measuring on-delay timer 43 starts measuring the time required for one stroke of the piston 13 by the supply of the descending stroke stroke interlocking pilot air. When the measured value of the down stroke measuring on-delay timer 43 reaches the measurement threshold value, the pilot air for integration stop using the air pressure supply source 10 as a supply source is sent out, and the first integration operation control switching valve 36 is integrated. Switch to the pilot air delivery stop state.

According to this configuration, when the air pump 12 is not idle, the measured values of the up stroke measuring on-delay timer 42 and the descending stroke measuring on-delay timer 43 are measured before one stroke of the piston 13 is completed. The total stop pilot air is sent out from the ascending process measurement delay release valve 33 and the descending stroke measurement delay release valve 34. As a result, the first integrated operation control switching valve 36 and the second integrated operation control switching valve 37 stop sending the integrated pilot air.
Further, when the air pump 12 is idle, the state in which the cumulative stop pilot air is not sent from the ascending process measurement delay release valve 33 and the descending stroke measurement delay release valve 34 continues. Continue to be sent to. As a result, the integration on-delay timer 53 continues to integrate, so that the integrated value reaches the determination threshold.

  Further, the determination means 50 includes a determination delay release valve 51 including an integration on-delay timer 53 that integrates the time required for one stroke of the piston 13 by supplying the integration pilot air. In a state where the air pump 12 is not idle, the supply of the pilot air for integration stops before one stroke of the piston 13 is completed, so that the integration on-delay timer 53 is before the integrated value reaches the determination threshold value. Then, the integration is finished. When the air pump 12 is idle, the integration pilot air continues to be sent, so that the integration on-delay timer 53 continues to integrate. When the integrated value of the integration on-delay timer 53 reaches the determination threshold value, the determination delay release valve 51 sends out the idle determination air.

  Further, the idle driving detection device 20 includes a pump control switching valve 24. The pump control switching valve 24 has a function of switching the pump drive switching valve 14 for supplying air from the air pressure supply source 10 to the air pump 12 to a closed state by supplying the air-running determination air. According to this configuration, when the idle driving determination air is detected and the idle driving determination air is sent out, the pump drive switching valve 14 is closed and the supply of air to the air pump 12 is stopped. It is possible to prevent 12 from remaining idle.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In the above embodiment, the measuring means includes the integration operation control switching valve and the measurement delay release valve. However, the measurement means includes at least one of the integration operation control switching valve and the measurement delay release valve. The structure which is not provided may be sufficient.
(2) In the above-described embodiment, the determination unit includes the determination delay release valve. However, the determination unit may not include the determination delay release valve.
(3) In the above embodiment, the air pump is stopped by the blank shot determination air, but a warning buzzer may be sounded or a warning lamp may be lit by the blank shot determination air. The warning buzzer, ringing, and lighting of the warning lamp may be executed simultaneously with the stop of the air pump, or may be executed instead of stopping the air pump.
(4) In the above embodiment, the time required for both the rising stroke and the lowering stroke of the piston is measured, but only one of the rising stroke and the lowering stroke of the piston may be measured. In this case, the number of the integral operation control switching valve and the measurement delay release valve constituting the measuring means may be one each.
(5) In the above embodiment, the case where the air pump is a reciprocating pump that pumps the paint in both the upward stroke and the downward stroke of the piston has been described. However, in the present invention, the air pump is an upward stroke of the piston. It can also be applied to a single-acting pump that pumps the paint only in one of the lowering stroke and the lowering stroke. In this case, the number of the integral operation control switching valve and the measurement delay release valve constituting the measuring means may be one each.
(6) In the above embodiment, the measurement threshold is set to 2.0 seconds, but the measurement threshold may be shorter than 2.0 seconds or longer than 2.0 seconds.
(7) In the above embodiment, the determination threshold value is set to 4.0 seconds, but the determination threshold value may be a time shorter than 4.0 seconds or a time longer than 4.0 seconds.
(8) In the above embodiment, the determination threshold is twice as long as the measurement threshold, but the determination threshold may be shorter than the measurement threshold or longer than the measurement threshold. Good.

DESCRIPTION OF SYMBOLS 10 ... Air pressure feed source 12 ... Air pump 13 ... Piston 14 ... Pump drive switching valve 20 ... Empty driving detection device 24 ... Pump control switching valve 30 ... Measuring means 33 ... Delay stroke release valve for measuring up stroke (delay valve for measurement) )
34 ... Delay release valve for down stroke measurement (delay release valve for measurement)
36... First integrated operation control switching valve (integrated operation control switching valve)
37. Second integration operation control switching valve (integration operation control switching valve)
42. On-delay timer for measuring the upward stroke (on-delay timer for measurement)
43 ... On-delay timer for down stroke measurement (on-delay timer for measurement)
50: Determination means 51 ... Delay open valve for determination 53 ... On-delay timer for integration

Claims (4)

An idle driving detection device for detecting an empty shot of an air pump in which a piston is driven by air supplied from an air pressure supply source and stroke-linked pilot air is supplied for each stroke of the piston using the air pressure supply source as a supply source. There,
Measurement of one-stroke required time of the piston is started by the supply of the stroke-linked pilot air, and the air pressure supply source is used as a supply source until the measured value of the required one-stroke time of the piston reaches a measurement threshold. Measuring means for sending out the integrating pilot air and stopping the sending out of the integrating pilot air when the measured value of the time required for one stroke of the piston exceeds the measuring threshold;
While the integration pilot air is being supplied, the time required for one stroke of the piston is integrated, and the air pressure supply source is supplied only when the load value for the time required for one stroke of the piston reaches the determination threshold. An air pump idle detection device, comprising: a determination unit that sends out an idle determination air as a source. The measuring means is
An integration operation control switching valve that switches to a state in which the integration pilot air can be sent out by supplying the stroke-linked pilot air;
A measurement on-delay timer that starts measuring the time required for one stroke of the piston by supplying the stroke-linked pilot air, and when the measurement value of the measurement on-delay timer reaches the measurement threshold, the air pressure supply source And a measurement delay release valve for sending the integration stop pilot air with the supply source as a supply source and switching the integration operation control switching valve to the delivery stop state of the integration pilot air. The air pump idle detection device according to claim 1.   The determination means includes an integration on-delay timer that integrates the time required for one stroke of the piston by supplying the integration pilot air, and when the integration value of the integration on-delay timer reaches the determination threshold, 3. The air pump idle detection device according to claim 1, further comprising a determination delay release valve that sends out the air determination air.   The pump control switching valve for switching a pump driving switching valve for supplying air from the air pressure supply source to the air pump by a supply of the idle driving determination air is provided. The air pump idle detection device according to any one of claims 1 to 3.

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