JP2015040517A - Diaphragm breakage detection device in hydraulic type diaphragm pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diaphragm breakage detection device in a hydraulic type diaphragm pump capable of surely detecting breakage of a diaphragm.SOLUTION: A diaphragm is energized to a backward movement side by energizing means, working fluid in a working fluid chamber is pressurized to a prescribed pressure so as to push back the diaphragm energized to the backward movement side by the energizing means to an initial position set in advance, and breakage of the diaphragm is detected based on a detection signal when decrease of the working fluid for the prescribed amount or more is detected by working fluid amount detecting means 20.

Description

  The present invention relates to a diaphragm breakage detection device in a hydraulic diaphragm pump that sucks and discharges a transport fluid.

  In the above-mentioned hydraulic diaphragm pump, the transfer fluid chamber and the working fluid chamber are isolated from each other by the diaphragm. For example, the working fluid chamber side is depressurized by the backward movement of the piston portion, so that the working fluid has the diaphragm on the returning side. Deforms to the room side. Thereby, the carrier fluid is sucked into the carrier fluid chamber through the suction port. After the suction of the transport fluid, the diaphragm is deformed to the transport fluid side, which is the forward movement side, by pressurizing the working fluid chamber side by the forward movement of the piston portion. As a result, the sucked carrier fluid is discharged from the carrier fluid chamber through the discharge port.

  By the way, the diaphragm may be damaged due to defective products or aging. A breakage detection device for detecting the breakage has already been proposed. This damage detection device includes a main tank that is a replenishment chamber for storing working fluid, a sub tank for taking out a part of the working fluid in the main tank and detecting oil level displacement, and an oil level of the sub tank. A floating body that floats and a detection switch for detecting excessive descent of the floating body are provided (see, for example, Patent Document 1).

Japanese Utility Model Publication No. 61-123893 (see FIGS. 1 and 2)

  However, the damage detection device of Patent Document 1 cannot detect that the diaphragm is practically (in fact) damaged. The reason will be described. First, the working fluid chamber side is depressurized as described above in order to suck the carrier fluid. Then, although the damaged diaphragm is not deformed, the carrier fluid is sucked into the carrier fluid chamber through the suction port by decompression. Part of the sucked carrier fluid flows into the working fluid chamber side through the damaged portion of the diaphragm. The flowing carrier fluid is mixed with the working fluid in the working fluid chamber. Subsequently, when the working fluid chamber is pressurized, the damaged diaphragm is not deformed, but a predetermined amount of mixed fluid flows into the conveying fluid chamber through the damaged portion of the diaphragm and is discharged from the discharge port. . Thus, during suction, the transport fluid flows from the transport fluid chamber to the working fluid chamber through the damaged portion of the diaphragm, and during discharge, the mixed fluid flows from the working fluid chamber to the transport fluid chamber. The amount of fluid does not continue to decrease or increase, and there is no change in the amount of fluid in the main tank. Therefore, the oil level of the sub tank is not substantially changed. For this reason, it is not possible to detect an excessive descent of the floating body. And the problem of continuing conveying the contaminated carrier fluid mixed with the working fluid occurs.

  In view of the above-described circumstances, the present invention provides a diaphragm breakage detection device in a hydraulic diaphragm pump that can reliably detect that a diaphragm is broken.

  In order to solve the above-described problems, a diaphragm breakage detecting device for a hydraulic diaphragm pump according to the present invention includes a carrier fluid chamber for sucking and discharging a carrier fluid by reciprocating motion based on the initial position of the diaphragm, A working fluid chamber that is isolated from the carrier fluid chamber by a diaphragm and that is supplied with a working fluid for deforming the diaphragm to the carrier fluid chamber side on the forward movement side, and for supplying the working fluid chamber to the working fluid chamber A main tank in which the working fluid is stored, and a reciprocating piston portion for revealing a supply state in which the working fluid in the main tank is supplied to the working fluid chamber and a return state in which the working fluid is returned to the main tank side A sub-tank connected to the main tank to detect a change in the working fluid by taking out a part of the working fluid in the main tank, and an operation in the sub-tank. A diaphragm breakage detecting device in a hydraulic diaphragm pump having a working fluid amount detecting means for detecting an increase / decrease of fluid, wherein the diaphragm is biased by a biasing means to a working fluid chamber side which is a return side. The pressure of the working fluid in the working fluid chamber is set so that the diaphragm urged to the backward movement side by the urging means is balanced at the initial position, and the working fluid more than a predetermined amount from the working fluid amount detecting means. It is characterized in that it is detected that the diaphragm is damaged based on a detection signal when a decrease in the frequency is detected.

  According to this configuration, for example, when the diaphragm is damaged when the working fluid chamber side is decompressed by sucking back the piston portion and the carrier fluid is sucked, the diaphragm is positioned on the return side by the biasing means. At the same time, the working fluid in the working fluid chamber whose pressure is increased so that the diaphragm is balanced at the initial position, that is, the working fluid having a pressure higher than that of the conveying fluid, is transferred from the main tank to the conveying fluid chamber side through the damaged portion of the diaphragm. Flows in. Due to the flow of the high-pressure working fluid, a predetermined amount of the transport fluid cannot be sucked into the transport fluid chamber from the suction port. When the working fluid chamber is pressurized and the transport fluid is discharged after the decompression, a predetermined amount of fluid corresponding to the pressurized portion is discharged from the transport fluid chamber through the discharge port. For this reason, since the working fluid in the main tank flows into the carrier fluid chamber each time the carrier fluid is sucked, the working fluid in the main tank decreases each time the carrier fluid is discharged. In conjunction with this, the working fluid in the sub-tank also decreases. By detecting that the amount of decrease in the sub-tank has become a predetermined amount or more by the working fluid amount detecting means, it is possible to reliably detect that the diaphragm is broken.

  Further, the diaphragm breakage detecting device in the hydraulic diaphragm pump of the present invention is such that, when the diaphragm is broken, the diaphragm is maintained in a state of being moved to the working fluid chamber side by the biasing means, and the piston portion In the return state to the main tank side, the working fluid flows from the main tank to the carrier fluid chamber side through the damaged portion of the diaphragm, and in the supply state in which the piston portion supplies the working fluid to the working fluid chamber side A configuration may be employed in which the working fluid that has flowed into is discharged as a carrier fluid.

  According to the above configuration, when the diaphragm is broken, the transport fluid cannot be sucked every time the transport fluid is sucked and discharged by reciprocating the piston portion, and the main tank is moved to the transport fluid chamber side. The working fluid into which the working fluid has flowed is discharged, and the working fluid in the main tank is reduced each time the piston part reciprocates.

  According to the present invention, the pressure of the working fluid in the working fluid chamber is set so as to balance the diaphragm at the initial position by providing the urging means for urging the diaphragm to the backward movement side. For this reason, when the diaphragm is damaged, the working fluid in the main tank is replenished and discharged every time the transport fluid is discharged, and the working fluid in the sub tank decreases. By detecting this reduction amount by the working fluid amount detection means, it is possible to reliably detect that the diaphragm is broken.

It is a schematic sectional drawing of a hydraulic diaphragm pump. Sectional drawing of the principal part of a hydraulic diaphragm pump is shown, (a) shows the state which is attracting | sucking carrier fluid, (b) has shown the state which has discharged | emitted carrier fluid. It is sectional drawing of the principal part of the hydraulic diaphragm pump which shows the state in which the diaphragm is damaged and the working fluid in the working fluid chamber flows into the carrying fluid in the carrying fluid chamber. It is a front view of a hydraulic diaphragm pump. It is a side view of a hydraulic diaphragm pump. It is a front view of a sub tank.

  Hereinafter, a hydraulic diaphragm pump will be described with reference to the drawings.

  FIG. 1 is a schematic cross-sectional view of a hydraulic diaphragm pump. The hydraulic diaphragm pump includes two fluid transfer units 1 and 1 for preventing pulsation, but the configuration is the same except that the timing of transferring the fluid is different. Only explained.

  As shown in FIGS. 2 (a) and 2 (b), one (right side) fluid conveyance unit 1 includes a diaphragm 2, a pump head (common to the other (left side) fluid conveyance unit 1) 3, A working fluid supply unit 4 that supports the pump 2 with the diaphragm 2 sandwiched between the pump head 3 and a gas discharge mechanism 5 provided above the working fluid supply unit 4 is provided. By combining the working fluid supply unit 4 and the pump head 3, one space is formed, and the diaphragm 2 that can reciprocate is disposed in the space, so that the carrier fluid chamber 6 and the working fluid chamber 7 are arranged. Partitioned. The carrier fluid chamber 6 is a chamber for sucking and discharging the carrier fluid by the reciprocating motion of the diaphragm 2, and the working fluid chamber 7 is isolated from the carrier fluid chamber 6 by the diaphragm 2, and the diaphragm 2 is This is a room in which a working fluid is supplied to be deformed to the transport fluid chamber side which is the forward movement side.

  In the working fluid supply unit 4, there is formed a working fluid restriction chamber 10 for accommodating a rod R as a rod-like member connected to the working fluid chamber 7 side of the diaphragm 2 and a valve body 8 attached to the rod R. Has been. A valve seat 9 is formed in the working fluid restriction chamber 10 so as to correspond to the valve body 8.

  The gas discharge mechanism 5 is provided to appropriately discharge gas (for example, air) mixed in the working fluid in the working fluid chamber 7 and the working fluid restriction chamber 10.

  The pump head 3 is provided with a suction side check valve 11 for sucking the transport fluid and a discharge side check valve 12 for discharging the sucked transport fluid. These check valves (not shown because the check valve of the left fluid transport unit 1 is behind the check valve of the right fluid transport unit 1) 11 and 12 are respectively a suction path 13 and a discharge path 14 is communicated with the transfer fluid chamber 6 via 14. Although not shown, the suction side check valve 11 is connected to a supply pipe for supplying a carrier fluid, and the discharge side check valve 12 receives the carrier fluid in the carrier fluid chamber 6 to receive a predetermined position. A discharge pipe for transporting up to is connected.

  Further, as shown in FIG. 1, the hydraulic diaphragm pump includes a driving force supply unit 15 that supplies the working fluid to the working fluid chambers 7 and 7 at an appropriate timing for reciprocating the diaphragms 2 and 2, and this drive And a drive unit 17 that drives an eccentric cam 16 constituting the force supply unit 15.

  As shown in FIGS. 1 and 4 to 6, the working fluid to be supplied to the working fluid chambers 7 and 7 is stored in the main tank 18. A sub tank 19 is connected to the main tank 18 in order to take out a part of the working fluid in the main tank 18 and detect increase / decrease in the working fluid. The sub-tank 19 is provided with a working fluid amount detection means 20 that detects increase / decrease of the working fluid in the sub-tank 19. The inner diameter of the sub tank 19 is very small compared to the inner diameter of the main tank 18, and the liquid level in the sub tank 19 changes greatly with a slight increase / decrease amount of the working fluid.

  The drive unit 17 includes an electric motor 21 that generates a rotational motion, and a gear unit 23 that transmits the rotational force from the electric motor 21 to the drive force transmission shaft 22.

  The drive force supply unit 15 includes the drive force transmission shaft 22 to which the rotational force from the electric motor 21 described above is transmitted, the eccentric cam 16 attached to the drive force transmission shaft 22, and the movement of the eccentric cam 16. Of the piston portions 24 and 25 that reciprocate in response to the first rotation shaft 27 supported by the inner ring of the bearing 26 in the first piston portion 24 and the bearing 28 in the other second piston portion 25. Provided in each piston part 24, 25 by appropriately energizing the first piston part 24 and the second piston part 25 in the second rotating shaft 29 supported by the inner ring and in the second piston part 25. A coil spring (not shown) as an urging means that functions to bring the rotating shafts 27 and 29 into contact with the eccentric cam 16, and a casing portion that is the main tank 18 containing these elements. With That.

  In the driving force supply unit 15, the working fluid is filled in a sealed space generated between the inner wall of the casing unit 18 and the piston units 24 and 25. The reciprocating motion of the piston portions 24 and 25 can reveal a supply state in which a working fluid in the main tank 18 described later is supplied to the working fluid chambers 7 and 7 and a return state in which the working fluid is returned to the main tank 18 side. .

  Moreover, as shown in FIG.1 and FIG.4, the cover bodies 30 and 31 are provided in the left-right both ends of the casing part 18. As shown in FIG. The lids 30 and 31 are provided with working fluid supply ports (a first supply port 30A and a second supply port 31A) so as to communicate with respective piping portions 32 and 33, which will be described later. The working fluid in the main tank (casing part) 18 reaches the diaphragms 2 and 2 from the end parts of the piston parts 24 and 25 through the supply ports 30A and 31A and the piping parts 32 and 33. The space formed between them is filled.

  Accordingly, the working fluid flows through the supply ports 30A and 31A by pressurizing or depressurizing the working fluid in the main tank 18 according to the movement of the piston portions 24 and 25. The diaphragms 2 and 2 reciprocate by this working fluid.

  The driving force supply unit 15 and the working fluid supply units 4 and 4 communicate with each other via the working fluid piping units 32 and 33. As described above, the working fluid supply units 4 and 4 and the working fluid piping units 32 and 32 Is filled with working fluid. Accordingly, the driving force from the driving unit 17 is transmitted to the diaphragms 2 and 2 through the working fluid, so that the diaphragms 2 and 2 are reciprocated.

  Further, as shown in FIG. 1, the hydraulic diaphragm pump is provided with coil springs 34 and 35 as urging means for urging the diaphragms 2 and 2 to the backward movement side. Therefore, the diaphragms 2 and 2 urged to the backward side by the coil springs 34 and 35 are balanced so as to be balanced at a preset initial position (in FIG. 1, a neutral position which is a substantially central position in the space). The pressure of the working fluid in the path supplied from the tank 18 into the working fluid chambers 7 and 7 is set.

  Further, it is possible to detect that the diaphragms 2 and 2 are damaged based on a detection signal when a decrease in the working fluid of a predetermined amount or more is detected from the working fluid amount detecting means 20.

  The working fluid amount detecting means 20 is means for detecting the level of the working fluid in the sub tank 19. Specifically, the working fluid amount detection means 20 is configured by a float type level sensor provided in the sub tank 19 as shown in FIGS. 4 to 6. The float type level sensor 20 includes a float 36 with a built-in magnet, a rod-shaped rod 37 that guides the float 36 and includes electrodes, and the float 36 moves up and down with respect to the rod-shaped rod 37 following the fluctuation of the liquid level. It has a detection unit 38 that detects the level of the liquid level by detecting the amount of change by changing the electrostatic capacity by moving. By detecting that the level of the detected liquid level has fallen below a preset liquid level, it is determined that the diaphragms 2 and 2 are broken (broken). Note that an air release portion 39 for releasing the inside of the sub tank 19 to the atmosphere is connected to the upper end of the sub tank 19.

  Next, the operation of sucking and transporting the transport fluid by a fixed amount using the hydraulic diaphragm pump configured as described above will be described.

  First, the electric motor 21 is driven, and the driving force is transmitted to the driving force transmission shaft 22. The eccentric cam 16 is rotated by the transmitted driving force. The rotation of the eccentric cam 16 causes the first and second piston portions 24 and 25 to reciprocate.

  By the reciprocating motion of the piston portions 24 and 25, a predetermined pressure that moves in a predetermined direction acts on the working fluid. When one piston portion 24 moves to the forward movement side, the path from the main tank 18 to the working fluid chamber 7 of one diaphragm is pressurized, and the other piston portion 25 moves to the backward movement side to move the main tank 18. To the working fluid chamber 7 of the other diaphragm is decompressed. As a result, the working fluid from the main tank 18 is supplied to the working fluid chamber 7 of one diaphragm 2, while the working fluid in the working fluid chamber 7 of the other diaphragm 2 is returned to the main tank 18. Become. For example, when the piston portion 25 moves to the backward side and the path is depressurized, the working fluid in the working fluid chamber 7 of one diaphragm 2 is returned to the main tank 18 side. Thereby, one diaphragm 2 deform | transforms into the working fluid chamber 7 side, as shown by the continuous line of Fig.2 (a) from the neutral position shown with the broken line of Fig.2 (a). Accordingly, the suction side check valve 11 is opened (with the discharge side check valve 12 closed) by moving the ball 11B of the suction side check valve 11 in the direction of the arrow (upward), and the suction port The carrier fluid is sucked (taken in) into the carrier fluid chamber 6 through a predetermined amount corresponding to the deformation of the diaphragm 2 through 11A.

  Subsequently, when the piston portion 25 moves from the backward movement side to the forward movement side and the path is pressurized, one diaphragm 2 is conveyed from the working fluid chamber 7 side as shown in FIG. Deformation toward the fluid chamber 6 side. As a result, the ball 12B of the discharge side check valve 12 is moved in the direction of the arrow (upward) to open the discharge side check valve 12 (with the suction side check valve 11 closed), and the discharge port The transport fluid is discharged through 12A and transported to a predetermined place.

  For example, when the diaphragm 2 is damaged when the piston 25 is moved to the backward movement side to reduce the path to one working fluid chamber 7 in order to suck the carrier fluid, the diaphragm 2 is restored by the biasing means 35. Located on the moving side. At the same time, the working fluid in the working fluid chamber 7 whose pressure is increased to balance the diaphragm 2 at the initial position (actually, the working fluid from the main tank 18 to the working fluid chamber 7), that is, the carrier fluid. As shown in FIG. 3A, the working fluid having a higher pressure flows into the conveying fluid chamber 6 through the damaged portion (hole) 2Z where the diaphragm 2 is damaged. Due to the flow of the high-pressure working fluid, the ball 11B is pressed down, and the transport fluid cannot be sucked into the transport fluid chamber 6 from the suction port 11A. After the pressure reduction, when the piston portion 25 is moved to the forward movement side to pressurize the working fluid chamber 7 and discharge the transport fluid, the ball 11B is raised and pressurized as shown in FIG. A predetermined amount of fluid corresponding to the amount is discharged from the discharge port 12A. For this reason, since the working fluid in the main tank 18 flows into the carrier fluid chamber 6 side every time the carrier fluid is sucked, the working fluid in the main tank 18 decreases every time the operation for discharging the carrier fluid is performed. In conjunction with this, the working fluid in the sub-tank 19 is similarly reduced. By detecting that the amount of decrease is greater than or equal to a predetermined amount by the working fluid amount detecting means 20 described above, it is possible to reliably detect that the diaphragm 2 is damaged. The amount of decrease detected by the working fluid amount detection means 20 can be arbitrarily set by the operator.

  When it is detected that the diaphragm 2 is damaged, an alarm device such as a buzzer, a lamp, or a sound device is activated, or a display means such as an electric bulletin board or a monitor is used to indicate that the diaphragm 2 is damaged. It is configured to notify the person or the like. Moreover, it is preferable to provide a forced stop means for stopping the operation of the hydraulic diaphragm pump simultaneously with the notification.

  In addition, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of this invention.

  In the above embodiment, the float type level sensor is used as the working fluid amount detecting means 20, but a laser type or ultrasonic type level sensor may be used. Further, instead of the sensor for measuring the liquid level, a weight sensor for measuring the weight of the working fluid detects that the change in weight is less than a predetermined weight set in advance and detects a breakage of the diaphragm. It may be.

  In the above embodiment, the diaphragm is detected by detecting that the working fluid has decreased. On the contrary, the increase in the working fluid is detected and the discharge check valve 12 is detected. A configuration for detecting an abnormality may also be added. That is, if the transport fluid sucked due to trouble such as the discharge-side check valve 12 being clogged cannot be discharged, the amount of working fluid in the sub tank increases every time the transport fluid is sucked, and the increased amount is a predetermined amount. Is detected by the detecting means, and abnormality of the discharge check valve 12 is detected based on the detection result. As the detection means, a weight sensor can be used in addition to the various level sensors described above.

  DESCRIPTION OF SYMBOLS 1 ... Fluid conveying part, 2 ... Diaphragm, 3 ... Pump head, 4 ... Working fluid supply part, 5 ... Gas discharge mechanism, 6 ... Conveying fluid chamber, 7 ... Working fluid chamber, 8 ... Valve body, 9 ... Valve seat, DESCRIPTION OF SYMBOLS 10 ... Working fluid restriction | limiting chamber, 11 ... Suction side check valve, 11A ... Suction port, 12 ... Discharge side check valve, 12A ... Discharge port, 13 ... Suction route, 14 ... Discharge route, 15 ... Driving force supply part, DESCRIPTION OF SYMBOLS 16 ... Eccentric cam, 17 ... Drive part, 18 ... Main tank (casing part), 19 ... Sub tank, 20 ... Working fluid amount detection means (float type level sensor), 21 ... Electric motor, 22 ... Driving force transmission shaft, 23 ... Gear part, 24, 25 ... Piston part, 26, 28 ... Bearing, 27, 29 ... Rotating shaft, 30, 31 ... Lid, 30A, 31A ... Supply port, 32, 33 ... Piping part, 34, 35 ... Biasing means (coil spring), 36 ... float, 3 ... bar-like rod, 38 ... detection unit, 39 ... open air section, R ... Rod

Claims (2)

A carrier fluid chamber for sucking and discharging the carrier fluid by reciprocating movement with respect to the initial position of the diaphragm, and a carrier fluid separated from the carrier fluid chamber by the diaphragm, and the diaphragm serving as a forward side A working fluid chamber to which a working fluid for deforming toward the chamber is supplied; a main tank in which the working fluid to be supplied to the working fluid chamber is stored; and the working fluid in the main tank to the working fluid chamber A piston part capable of reciprocating to reveal a supply state to be supplied and a return state to return to the main tank side, and a part of the working fluid in the main tank should be taken out to detect an increase or decrease in the working fluid Diaphragm in a hydraulic diaphragm pump comprising a sub tank connected to the main tank and a working fluid amount detecting means for detecting an increase or decrease in the working fluid in the sub tank A damage detection device,
The diaphragm is urged by the urging means to the working fluid chamber side which is the return side, and the working fluid in the working fluid chamber is balanced with the diaphragm urged to the return side by the urging means at the initial position. And detecting that the diaphragm is broken based on a detection signal when a decrease in the working fluid of a predetermined amount or more is detected from the working fluid amount detecting means. Diaphragm damage detector for hydraulic diaphragm pumps.   When the diaphragm is damaged, the diaphragm is maintained in a state of being moved to the working fluid chamber side by the urging means, and the main part is passed through the damaged part of the diaphragm in a return state in which the piston part is returned to the main tank side. The working fluid flows from the tank to the transport fluid chamber side, and the working fluid that flows into the transport fluid chamber side in the supply state where the piston portion supplies the working fluid to the working fluid chamber is discharged as the transport fluid. A diaphragm breakage detecting device in the hydraulic diaphragm pump according to claim 1.

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