JPH06336975A - Force-feed quantity detecting method for reciprocating positive displacement pump - Google Patents

Abstract

PURPOSE:To provide a force-feed quantity detecting method for a reciprocating positive displacement pump enabling the correct detection of force-feed quantity. CONSTITUTION:At the time of force-feeding conveyed material by a conveying pump piston-cylinder unit (a), the stroke number St per unit time of the pump piston-cylinder unit (a) is measured by a first and a second proximity switches 53, 53' for detecting a first and a second couplings 51, 51, and charging efficiency eta is obtained from the pressure waveform of the conveyed material discharged from the conveying pump piston-cylinder unit (a). Specific gravity rhois obtained by a density meter 58 and inputted into a control device 50. The control device 50 computes the force-feed quantity per unit time by an expression Q=VXStXetaXrho, where V is the volume of a conveying cylinder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting a pumping amount of a reciprocating type positive displacement pump, and more specifically, a pump piston / cylinder unit for pumping a conveyed product,
A reciprocating volumetric pump equipped with a drive piston / cylinder unit for driving this pump piston / cylinder unit and a circuit switching valve for switching a hydraulic circuit for supplying / discharging pressure oil to / from these units is used to pump a conveyed product under pressure. The present invention relates to a pressure feed amount detection method for detecting the pressure feed amount at that time.

[0002]

2. Description of the Related Art For example, a reciprocating type positive displacement pump for pressure-feeding a highly viscous substance such as sludge is well known in the art without mentioning a literature name, and is generally composed of a cylinder and a piston. By the backward movement, the conveyed product is sucked into the cylinder, and by the forward movement, it is pumped from the discharge port. The reciprocating double-row type positive displacement pump is also the same in principle, and a plurality of piston / cylinder units are alternately driven. Such a reciprocating double-row positive displacement pump is disclosed in Japanese Patent Application No. 58-606 by the present applicant.
No. 62 proposed. This reciprocating double-row positive displacement pump is provided with a pair of pump piston / cylinder units for pressure-feeding a conveyed object, a driving piston / cylinder unit for alternately driving the units, and corresponding units. And a circuit switching valve for appropriately switching the hydraulic circuit.

A pump piston / cylinder unit for carrying is provided with a suction port for sucking a product and a discharge port for discharging it, and these suction port and discharge port are opened and closed by an operating cylinder. An on-off valve is provided. A pilot valve is provided at the stroke end of the piston of the driving piston / cylinder unit, and the circuit switching valve is switched by the pilot pressure of these pilot valves.
Pressure oil is supplied to and discharged from the operating cylinder, and pressure oil is also supplied to and discharged from the driving piston / cylinder unit, whereby the pump piston / cylinder unit is alternately driven and the conveyed product is pumped from the discharge port. It has become so. Further, the present applicant has also proposed a reciprocating double-row positive displacement pump capable of pumping in both forward and reverse directions by improving the reciprocating double-row positive displacement pump, a pulsation-free reciprocating double-row positive displacement pump, and the like. -308347, 3-308348, 3-318591 and the like.

In the reciprocating double-row positive displacement pump as described above,
For example, when incinerating sewage sludge, human waste sludge, etc.,
It is important to know the flow rate per unit time, that is, the pumping amount, in relation to the treatment plan. Therefore, the discharge pipe of this type of positive displacement pump is provided with an electromagnetic flow meter, an ultrasonic flow meter, a rotary flow meter, and the like.

[0005]

As described above, since the reciprocating type positive displacement pump is provided with the flowmeter, it is possible to grasp the pressure-feeding amount for a while, but the conventional method for detecting the flowrate of the conveyed object is used. Has various drawbacks. For example, a rotary flow meter has a structure in which a rotor is provided in a pipe and the rotor is rotated by a fluid to be pumped, so that there is no problem in measuring the flow rate of a fluid having a relatively low viscosity, but such as sludge. There is a large error in the measurement of highly viscous conveyed items, which is not practical. In addition, an electromagnetic flowmeter creates a magnetic field in the pressure-feeding tube and when the object is pumped, it acts as a conductor that moves the object, causing an electromotive force in the object. Is to ask.
Then, the flow rate is measured by multiplying the flow velocity by the pipe diameter of the pressure feeding pipe.
By the way, since the electromotive force between the electrodes is proportional to the flow velocity of the conveyed material which is a conductor, the electromotive force is small when the flow velocity is slow, and measurement may be impossible.

Further, the ultrasonic flowmeter has the same drawback. That is, the ultrasonic flowmeter is provided with an ultrasonic transmitter and a receiver at a predetermined interval in the pressure-feeding pipe, and the time during which the ultrasonic wave propagates in the conveyed object being pressure-fed and the same distance at a stationary time. Since the pumping speed is measured by comparing the time of propagation through the inside and the difference, the time difference may be small and the measurement error may be large if the pumping speed is small. Further, the time or speed at which the ultrasonic wave propagates in the conveyed product depends on the density, the temperature, etc., therefore, for measuring the flow rate of the conveyed product such as dehydrated cake containing air,
It is necessary to correct the temperature and the like, which is a practical problem.
It is an object of the present invention to provide a method for detecting the pumping amount of a reciprocating type positive displacement pump which is completely different from the conventional detecting method having the above-mentioned drawbacks.

[0007]

In order to achieve the above object, a pump piston / cylinder unit for transportation is connected to the pump piston / cylinder unit to drive the piston / cylinder. When the product is driven by a unit and the product is pumped from the pump piston / cylinder unit for carrying, the filling efficiency η of the product is obtained from the pressure waveform of the product or the pressure waveform of the driving piston / cylinder unit, It is configured to calculate the pumping amount by the following equation. Q = V × St × η × ρ where Q: pumping amount per unit time St: number of strokes per unit time of the pump piston / cylinder unit η: filling efficiency ρ: specific gravity of the conveyed product V: of the conveying cylinder Volume The invention according to claim 2 is the specific gravity ρ of the conveyed product according to claim 1.
Is automatically measured and calculated.

[0008]

[Function] The pressure oil is supplied to and discharged from the driving piston / cylinder unit, the pump piston / cylinder unit for driving is driven, and the transported object is pressure-fed. At this time, the pressure waveform of the conveyed product discharged from the conveying pump piston / cylinder unit draws a certain pattern. For example, one of the pistons
In terms of per stroke, the pressure is low in the initial stage of the pushing stroke of the piston, which is a so-called ineffective pressure that does not contribute to the pumping, and becomes a predetermined pressure effective for the pumping after a lapse of a predetermined time. From the ineffective pressure and the effective predetermined pressure, the filling efficiency η of the conveyed object in the conveying cylinder is obtained. Alternatively, the driving piston
Since the pressure waveform for driving the cylinder unit is substantially the same as the pattern of the pressure waveform of the conveyed product, the filling efficiency η is obtained from the waveform of the driving pressure of the driving piston / cylinder unit. Then, for example, it is input to the control device. The specific gravity ρ of the conveyed product is measured in advance and input to the control device. The volume V of the transfer cylinder is also input in advance. Then, the control device counts the number of strokes St of the pump piston / cylinder unit per unit time by a signal from, for example, a proximity switch, and calculates the pressure feed amount per unit time by the formula: Q = V × St × η × ρ And output. According to the second aspect of the present invention, the specific gravity of the conveyed product is automatically measured and input to, for example, the control device. Then, the control device similarly calculates the pressure feed amount per unit time by the formula Q = V × St × η × ρ and outputs it.

[0009]

The present invention can be implemented in various forms. For example, a single type reciprocating positive displacement pump having one pump piston / cylinder unit for transportation can be used. At this time, the reciprocating type positive displacement pump has a stroke for sucking the conveyed material and a stroke for discharging the conveyed object, so that the discharge pressure is intermittent. On the other hand, if the pump piston / cylinder unit is, for example, two reciprocating double-row positive displacement pumps, when one pump is in the suction stroke, the other pump is in the discharge stroke, so the discharge pressure is tentatively continuous. It will be what you did.

However, no matter which reciprocating positive displacement pump is used, the pressure of the conveyed product shows a certain waveform. Since this waveform represents the filling efficiency of the conveyed product, the filling efficiency can be obtained from this waveform. Further, the waveform of the hydraulic pressure of the driving piston / cylinder unit that drives the transport pump piston / cylinder unit is substantially the same as the pressure waveform of the transported object. Therefore, the drive piston
It is also possible to obtain the filling efficiency of the conveyed product from the waveform of the hydraulic pressure of the cylinder unit.

The number of strokes of the pump piston / cylinder unit for transportation can be counted at various points. For example, a proximity switch is provided on the driving piston / cylinder unit, and the number of operations of the proximity switch is counted,
It is also possible to obtain the number of strokes of the pump piston / cylinder unit per unit time. In addition, counting the number of times the valve that supplies and discharges pressure oil to and from the driving piston / cylinder unit is counted, and the number of changes in the discharge pressure waveform or drive pressure waveform of the reciprocating volume pump is also counted. The number of strokes can also be obtained.

However, as a first embodiment,
The pump is implemented as a reciprocating double-row positive displacement pump, the filling efficiency of the conveyed product is determined from the pressure waveform of the conveyed product, and the number of strokes per unit time of the pump piston / cylinder unit is compared with the driving piston / cylinder unit. Explain an example of measuring with a proximity switch provided outside the water chamber box between the pump piston / cylinder unit for transport and the specific gravity of the transported product with an automatic measuring device provided in the discharge pipe for pressure feeding. To do. In addition, as a second embodiment, a reciprocating double-row positive displacement pump with less pulsation is applied, and the filling efficiency of the conveyed material is obtained from the pressure waveform of the hydraulic pressure supplied to the driving piston / cylinder unit. An example of implementation will be described.

FIG. 1 is a diagram showing a first embodiment of the present invention. As shown in FIG. 1, the reciprocating double-row positive displacement pump according to the present embodiment has a pump piston / cylinder unit. A part a, a drive piston / cylinder unit part b, a circuit switching valve part c, a control device 50 and the like are provided.

Pump piston / cylinder unit a
Includes a pair of first and second pump cylinders 1, 1 '. In the respective pump cylinders 1 and 1 ', first and second pump pistons 2 and 2'are provided so as to be reciprocally movable, and the rods thereof are the first and second pump piston / cylinder unit parts b. The first and second couplings 51, 51 'to the rods 3, 3'of the driving pistons 13, 14 of
Are respectively connected via. Between the pump piston / cylinder unit part a and the drive piston / cylinder unit part b, a water chamber box 52 is provided which exerts a cushioning action and a cooling action of these unit parts a and b. The first and second couplings 51 and 51 'reciprocate in the pump cylinders 1 and 1'and in the water chamber box 52, but these couplings 5 are provided outside the water chamber box 52.
First and second proximity switches 53 for detecting the number of strokes of the first and second pump pistons 2 and 2 ′ of the pump piston / cylinder unit a, that is,
53 'is provided. These proximity switches 53,
53 'is connected to the controller 50 by signal lines 55, 55'. The control device 50 is composed of, for example, a microcomputer, and has a counting function of counting the stroke numbers of the first and second pump pistons 2 and 2 ′ that are counted by the first and second proximity switches 53 and 53 ′. It has a calculation function to calculate the quantity.

Valve bodies 4 and 4'for opening and closing the suction ports are provided on the head side portions of the first and second pump cylinders 1 and 1 '.
Further, valve elements 7 and 7'for opening and closing the discharge port are provided at the front end portion. Then, the discharge port becomes one common discharge pipe 10 and is appropriately connected to the secondary side pipe. These valve elements 4, 4 ', 7, 7'are opened and closed by operating cylinders 5, 5'8, 8'provided in the pump piston / cylinder unit a. According to the present embodiment, a pressure gauge 56 for measuring the pressure of the conveyed product is provided in the discharge pipe 10 in order to obtain the filling efficiency required when calculating the pressure feed amount. The pressure signal of the conveyed object detected by the pressure gauge 56 is supplied to the control device 50 via the signal line 57.
The control device 50 calculates the filling efficiency η of the conveyed product from the input pressure waveform. In addition, the discharge pipe 10 for pressure feeding
Is provided with an on-line piping densitometer 58 manufactured by Earthnix Co., Ltd., so that the density, ie, the specific gravity, of the transported object measured by the densitometer 58 is input to the control device 50 via a signal line 59. Has become.

The drive piston / cylinder unit b is also
A pair of first and second drive cylinders 11 and 12 and first and second drive pistons 13 and 14 that are reciprocally provided therein are provided. The first and second drive cylinders 11 and 1 of the drive piston / cylinder unit b
2 are communicated with each other by a conduit 40 on the rod side thereof. The pilot valve 1 is provided at both the push stroke end position and the pull stroke end position of the first drive cylinder 11.
5 and 16 are provided, respectively. Further, cushion valves 17 and 18 are provided at both the push stroke end position and the pull stroke end position of the second drive cylinder 12, respectively. The specific construction and operation of the cushion valves 17, 18 and the pilot valves 15, 16 have been described in detail in the above-mentioned Japanese Patent Application No. 58-60662, and therefore their explanations are omitted here.

The circuit switching valve section c includes an open center type first two-way switching valve 19A and a second two-way switching valve 19B.
And the first two-way switching valve 19A is
At a pressure of 6, 26 ', and the second two-way switching valve 19B,
Each spool 2 with pilot pressure described later in detail
1, 22 are driven, and the flow direction of the pressure oil can be switched appropriately. And these pump pistons
The cylinder unit part a, the drive piston / cylinder unit part b, and the circuit switching valve part c are connected to each other by a pipe line as described below.

Ports D and C of the second two-way switching valve 19B
The main pipelines 26, 26 'are connected to. Main pipeline 2
6'extends toward the pump piston / cylinder unit a and is connected to the cylinder head side of the operating cylinder 8 '. First branch line 27 branched from the main line 26 '
Is connected to the piston rod side of the operating cylinder 8, the second branch conduit 28 is connected to the piston rod side of the operating cylinder 5 ′, and the third branch circuit 29 is connected to the cylinder head side of the operating cylinder 5. Has been done. A pressure reducing valve 46 'with a check valve is installed in the main pipe 26', and flow rate adjusting valves 47, 47 'with a check valve are installed in the first branch pipe 27 and the second branch pipe 28, respectively. There is. Main line 2
From 6 ', a conduit 30' is branched, and this conduit 30 'is connected to a port M of the two-way switching valve 19A via a throttle valve 31'.

A pressure reducing valve 46 with a check valve is also interposed in the main pipe line 26, and the main pipe line 26 further extends toward the pump piston / cylinder unit portion a, and the operating cylinder 8
The first branch conduit 40 connected to the cylinder head side of the main cylinder 26 is connected to the rod side of the operating cylinder 8 '. The second branch conduit 41 is connected to the cylinder head side of the operating cylinder 5 ′, and the third branch conduit 42 is connected to the rod side of the operating cylinder 5. Flow control valves 48 ′ and 48 with check valves are provided in the first and third branch pipes 40 and 42, respectively. A pipe 30 branches off from the main pipe 26, and the pressure oil in the main pipe 26 is applied to the port K of the first two-way switching valve 19A via a throttle valve 31 provided in the pipe 30. It has become so.

A hydraulic pressure source P is connected to a line 32 between the first two-way switching valve 19A and the second two-way switching valve 19B, and a line 33 is connected to a tank T, respectively. First two
At the ports A and B of the directional control valve 19A, the discharge pipes 34 and 3 are provided.
5 are connected respectively, and these discharge pipes 34, 35 are connected to the head side of the second and first drive cylinders 12, 11 of the drive piston / cylinder unit part b. The discharge pipes 34, 35 are connected to pilot pipes 38 ', 38 via check valves 36', 36, respectively.

Pilot valves 15 and 16 are provided near both ends of the first drive cylinder 11, respectively, and pilot pipes 37 and 37 'extend from these pilot valves 15 and 16, respectively. 37 is the second 2
The pilot port H of the directional control valve 19B and the pilot pipe 37 'are connected to the pilot port G of the second two-way control valve 19B.

Next, the operation of the above embodiment will be described. First, the state shown in FIG. 1 will be described. The pressure oil supplied from the hydraulic power source P is the port C of the second two-way switching valve 19B.
To the main pipe line 26 '. On the other hand, since the main pipe line 26 is connected to the tank T, no pressure is generated. Therefore, the pressure oil from the main pipe line 26 'is reduced in pressure by the check valve 46'.
The pressure is reduced to a predetermined value and is supplied to the operating cylinders 5 ', 8, 5 and 8', the valve body 4'and the valve body 7 are opened, and the valve body 4 and the valve body 7'are closed.

On the other hand, the driving pressure oil from the hydraulic pressure source P is the first
It is discharged from the port B to the discharge pipe 35 through the two-way switching valve 19A and is supplied to the head side of the first drive cylinder 11. Since the discharge pipe 34 is short-circuited to the tank T,
No pressure is generated on the head side of the second drive cylinder 12. Therefore, the first driving piston 13 moves to the left in the drawing and is in the pushing stroke. The first pump piston 2 of the pump piston / cylinder unit portion a directly connected to this is also in the pushing stroke, and the conveyed product in the first pump cylinder 1 is pressure-fed from the discharge pipe 10. Since the first drive piston 13 of the drive piston / cylinder unit part b moves leftward, the pressure oil in the first drive cylinder 11 is supplied to the rod side of the second drive cylinder 12 via the conduit 40. Second
The driving piston 14 moves to the right. That is, it is a pulling stroke. Therefore, the pump piston / cylinder unit a
The second pump piston 2'also goes to the right, and the next object to be pumped is sucked into the second pump cylinder 1'as indicated by the chain line arrow. The second drive piston 14 of the drive piston / cylinder unit b is the drive cylinder 1
When reaching the left end of 2, the shock is buffered by the action of the cushion valve 18.

When the first driving piston 13 of the driving piston / cylinder unit portion b moves to the left and reaches the end portion, the pilot valve 15 operates as described in the above-mentioned Japanese Patent Application No. 58-60662, The pilot pressure is applied to the port H of the second two-way switching valve 19B via the pilot pipe 37, the spool 21 of the second two-way switching valve 19B is switched, and the hydraulic power source P is connected to the main pipe line 26. Then, the pressure oil depressurized by the check valve-equipped pressure reducing valve 46 is supplied to the operating cylinders 5, 8 ', 5', 8 this time, the valve bodies 4 and 7'are opened, and the valve body 4 ' The valve body 7 is closed. The driving pressure oil from the hydraulic pressure source P is applied to the port K of the first two-way switching valve 19A via the conduit 30 and the other port M.
Since no pressure oil acts on the first two-way switching valve 1
The spool 21 of 9A is also switched, and the pressure oil is discharged from the port A to the discharge pipe 34 through the first two-way switching valve 19A and is supplied to the head side of the second drive cylinder 12 of the drive piston / cylinder unit part b. It Therefore, the second drive piston 14 moves left in the figure, and the second pump piston 2'of the pump piston / cylinder unit a also moves left. Since the pump piston 2'moves to the left, the conveyed product in the first pump cylinder 1'is the discharge pipe 1
It is pumped from 0. Since the second driving piston 14 of the driving piston / cylinder unit part b moves leftward, the pressure oil is supplied to the rod side of the first driving cylinder 11 via the conduit 40, and the first driving piston 13 moves to the right. To go. Therefore, the first pump piston 2 of the pump piston / cylinder unit a also moves to the right, and the conveyed object to be pumped next as described above is sucked into the first pump cylinder 1. Thereafter, the above-described operation is alternately repeated so that the conveyed product is the discharge pipe 1 of the pump piston / cylinder unit a.
It is pumped from 0. When changing the pressure feeding direction, although not shown in the figure, a two-way switching valve is provided in the main pipelines 26, 26 ', and this valve is switched to change the spool position. Then, the valve position of the drive piston / cylinder unit b does not change, but the main line 2
The reverse pressure oil described above acts on 6, 26 ', and the direction of pressure transfer changes.

As described above, the first and second couplings 51 and 51 'reciprocate when the conveyed object is pressure-fed,
It acts on the first and second proximity switches 53, 53 '. First,
The two-proximity switches 53 and 53 ′ detect this, and the signal is input to the control device 50 through the signal lines 55 and 55 ′. The control device 50 includes a piston 2 for the first and second pumps,
The number of reciprocating motions, that is, the number of strokes per unit time of 2 ', for example, every minute, is counted and stored. The volumes V 1 and V 2 of the first and second pump cylinders 1 and 1 ′ are input to and stored in the control device 50. The specific gravity ρ of the conveyed product is measured by the densitometer 58 and input to the control device 50 through the signal line 59. The control device 50 stores the average specific gravity ρ of the conveyed product for a predetermined time.

The charging efficiency η is calculated by the controller 50. That is, the pressure gauge 56 provided in the discharge pipe 10
Shows the pattern as shown in FIG. 3 because the carrier pressure is measured and input to the control device 50 because the pump is reciprocating. For example, looking at the first stroke A1st of the first pump piston 2,
The period t2 at the beginning of the first stroke A1st is the first period t2.
The pump piston 2 has just entered the pushing stroke, and the reactive pressure has not reached the predetermined discharge pressure. However, after the time t2, it becomes the predetermined pressure effective for the pressure feeding. Therefore, the charging efficiency η ' ₍₁₎ can be obtained from the ratio of the time t of the first stroke A1st to the time t1 of reaching the predetermined pressure by the charging efficiency η' ₍₁₎ = t1 / t × 100. For example, in the first stroke A1st, since the period t2 of the invalid pressure is extremely short, the time t1 effective for the pressure feeding is the first stroke A1st.
Almost equal to the time t of 1st, and the charging efficiency η ′ is about 95 to 1
It is 00%. In the second stroke A2st of the first pump piston 2, the time t2 when the predetermined discharge pressure is not reached is about 1/3 of the time T of the second stroke A2st.
Therefore, t1 becomes 2 / 3t, and the packing efficiency η '
₍₂₎ is t1 / t × 100 = 2 / 3t ÷ t × 100 = 66
%. In the same manner, the charging efficiencies η ' ₍₃₎ , ₍₄₎ , are calculated. The waveforms of the first, second, and strokes obtained by the second pump piston 2 ′ are B1st and B2s.
, t ,,. From this waveform, the filling efficiency η ″ ₍₁₎ , ₍₂₎ , can be similarly obtained. The control device 50 calculates the total filling efficiency from the thus obtained pressure waveform pattern for each stroke, and calculates and stores the average filling efficiency η for a predetermined number of strokes. Then, the pressure-feeding amount T / H per hour is calculated by the formula Q = V × St × η × ρ × 60 and output to an output device such as a display or a printer. Since the filling efficiency η is proportional to the waveform of the conveyed product, the area of the waveform can be integrated and calculated from the ratio to the set area.

According to this embodiment, the number of strokes per minute of the first and second pump pistons 2 and 2'is counted by the non-contact first and second proximity switches 53 and 53 '. Despite measuring sludge and other transported items,
There is no problem of wear and accurate counting is possible over a long period of time.

The following table shows the measured values when the sludge was pressure-fed by the method of the above embodiment using the pressure gauge 56 and the actually measured values. Table Sampling date and time 1992 Displayed on the control device Measured value (pressure feed amount according to this example) (value manually measured) December 2 Stroke number Pressure feed amount Specific gravity Pressure feed amount Specific gravity Water content rate (/ min) (T / H ) (T / H) (%) 13:55 23.1 1.61 3.07 1.7 31.3 14:50 23.2 1.61 3.15 1.7 32.0 35:00 50 minutes 2 2.9 1.58 2.92 1.7 32.0 In the above table, the measurement unit time of the pumping amount according to this example is 30 minutes, and the specific gravity is the density meter shown in FIG. This is the value actually measured at 58. Further, the manually measured value in the table is a value obtained by directly weighing the amount discharged from the discharge pipe 10, and the specific gravity is a value obtained by actually measuring the discharged material to be discharged. As is clear from the above table, according to the present embodiment, the pressure feed amount can be detected with an accuracy of 95% or more.

Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment can also be implemented in various forms. For example, when the stroke of the drive piston / cylinder unit is switched, it is possible to provide a proximity switch that detects the position of the piston without coming into contact with an object, and switch the directional control valve according to the detection signal. When the proximity switch is used, the detection unit including an oscillation circuit and a bridge circuit can be provided on the cylinder side of the pump piston / cylinder unit or the cylinder side of the drive piston / cylinder unit. It can also be provided in association with a rod coupling that is commonly provided in these cylinder units. When the proximity switches are used as described above, the number of strokes of the piston of the pump piston / cylinder unit can be counted by these proximity switches. Further, when the proximity switch is used, there is an advantage that flexibility is provided in the arrangement of the detection unit, and the detection unit can be moved to adjust the switching timing of the directional control valve. However, the figure only shows an example implemented with a pilot valve. When using a pilot valve, it is desirable to adjust the switching timing of the directional control valve by providing a plurality of ports in the cylinder with a predetermined interval and using these ports appropriately. An embodiment is shown in which two pilot valves are provided on the cylinder of the unit part.

FIG. 2 is a diagram showing a second embodiment of the present invention. The reciprocating double-row positive displacement pump according to this embodiment also has a pump piston / cylinder unit a'and a drive piston / cylinder unit. Part b ', circuit switching valve part c',
The control device 60 and the control device 60 are roughly connected, and these are appropriately connected by rods, pipes, and the like.

Pump piston / cylinder unit a '
Is a pair of first and second pump cylinders 101, 111
And so on. And the first and second pump cylinders 1
In 01 and 111, the first and second pump pistons 10 are provided.
2, 112 are provided so as to be reciprocally movable, and the first and second rods 103, 11 of these pump pistons 102, 112 are provided.
3 extends toward the drive piston / cylinder unit b ′ to the first and second drive pistons 121, 131 of the drive piston / cylinder unit b ′ via the first and second couplings 191 and 192. Each is combined.

First and second pump cylinders 101, 11
The first suction port 109, 119 on the front side of the first
However, first and second discharge ports 105 and 115 are formed at the front end portion, respectively. Then, in order to open and close the first and second suction ports 109 and 119, the first and second suction ports are provided.
Open / close valves 104 and 114 of the first and second discharge ports 10
First and second on-off valves 106 and 116 for discharging are provided to open and close 5, 115, respectively. These first and second discharge ports 105 and 115 serve as one common discharge pipe 110, which is appropriately connected to a secondary side pipe or the like. The first and second suction ports 109 and 119 are also not shown in the figure, but they are appropriately integrated into one by a pipe line.

As in the first embodiment, the discharge pipe 110 for pressure feeding is provided with a specific gravity meter, for example, an online piping densitometer 68 manufactured by Earthnix Co., Ltd. That is, the specific gravity is input to the control device 60 via the signal line 69.

Pump piston / cylinder unit a '
Further includes first and second on-off valves 104 and 114 for suction.
First and second operation cylinders 107, 1 for suction for operating
17, and first and second discharge operation cylinders 108 and 118 for operating the first and second discharge on-off valves 106 and 116.
And are provided respectively.

The drive piston / cylinder unit b'also has a pair of first and second drive cylinders 120, 130.
And first and second drive pistons 121 and 131 that are reciprocally provided therein. First,
First and second piston rods 122 and 132 are coupled to the second driving pistons 121 and 131 by known means, and these rods 122 and 132 are the first and second piston piston / cylinder unit parts a ′. The first and second couplings 191, 1 to the second rods 103 and 113.
It is connected via 92. The first and second piston rods 122 and 132 have a predetermined diameter size or a predetermined volume at least in the driving first and second cylinders 120 and 130.

Pump piston / cylinder unit a '
And a drive piston / cylinder unit b'is provided with a water chamber box 62 for cooling and buffering these unit a ', b'. First and second above
The couplings 191 and 192 of the above reciprocate mainly in the water chamber box 62.
First and second detection of reciprocating movement of the two couplings 191 and 192, that is, the number of strokes of the pump pistons 102 and 112 of the pump piston / cylinder unit a '.
Proximity switches 63, 63 'are provided. These proximity switches 63, 63 'are connected to the signal lines 65, 6
5'is connected to the control device 60.

First and second drive cylinders 120, 130
The first and second pilot valves 123 and 133 are provided at predetermined positions in the vicinity of the push stroke end portions of the above, and the third and fourth pilot valves 124 and 13 are provided at the push stroke end portions.
4 are provided respectively. These pilot valves 123, 133, 124, and 134 extract pilot pressure for operating a two-way switching valve, which will be described in detail later. Further, the first and second drive cylinders 120, 13
At the pull stroke end position of 0, the cushion valves 125, 13
5 are provided respectively, but these cushion valves 1
The specific constructions and operations of Nos. 25 and 135 have been described in detail in the above-mentioned Japanese Patent Application No. 58-60662, and therefore their explanations are omitted here.

The circuit switching valve portion c'includes open center type first and second two-way switching valves 140 and 141 and third and fourth two-way switching valves 150 and 151. First two
The line 160 allows the pilot pressure of the third pilot valve 124 to be applied to the port 160 of the direction switching valve 140. Similarly, the second two-way switching valve 14
The same pilot pressure is applied to the first port 162.
The pilot pressure of the second pilot valve 133 is applied to the other ports 161 and 163 of the two-way switching valves 140 and 141 by the line 171, and the ports 164 and 166 of the third and fourth two-way switching valves 150 and 151 are used. Line 172 to the pilot pressure of the first pilot valve 123, and ports 165 and 167 to the line 173 to the fourth pilot pressure.
The pilot pressure of each pilot valve 134 is applied. And these pump pistons
The cylinder unit part a ', the drive piston / cylinder unit part b', and the circuit switching valve part c'are connected to each other by a hydraulic line as described below.

Ports O and Q of the first two-way switching valve 140
Is connected to a first drive conduit 142 and a second drive conduit 143, respectively, and these conduits 142 and 143 are connected to the cylinder head side and the rod side of the driving first cylinder 120, respectively. ing. Third two-way switching valve 15
The third drive pipe line 152 and the fourth drive pipe line 153 are connected to the ports S and R of 0, respectively.
Reference numerals 2 and 153 are respectively connected to the cylinder head side and the rod side of the second driving cylinder 130. A first operation pipe line 144 and a second operation pipe line 145 are connected to the ports V and U of the second two-way switching valve 141, respectively. These conduits 144 and 145 extend toward the pump piston / cylinder unit a ', and the first operation conduit 144 branches to form a rod side of the first operation cylinder 107 for suction and a first operation cylinder 107 for discharge. Each of them is connected to the head side of one operation cylinder 108.

According to the present embodiment, the first drive line 142 is used in order to obtain the filling efficiency required when calculating the pumping amount.
The first and second pressure gauges 66 and 66 ′ for measuring the pressure of the conveyed product are provided in the third drive pipe 152. The pressure signal of the pressure oil detected by the first and second pressure gauges 66 and 66 'is input to the control device 60 through the signal lines 67 and 67', and the control device 60 detects the pressure wave from the input pressure waveform. The filling efficiency η is calculated. Note that the control device 60 is composed of, for example, a microcomputer as in the control device 50 of the first embodiment described above, and the first and second pump pistons 102 and 112 are provided.
Is provided with a counting function for counting the number of strokes, a calculation function for calculating a pressure feed amount described later, and the like.

The second operation pipe line 145 extends toward the pump piston / cylinder unit portion a'and branches to the head side of the first operation cylinder 107 for suction and the first operation cylinder 108 for discharge. Are connected to the rod side of each. A first variable throttle valve 180 with a check valve is provided in the vicinity of the first operation cylinder 108 for discharging the second operation pipe line 145. Third and fourth operation pipe lines 154 and 155 are connected to the ports W and Y of the fourth two-way switching valve 151, and these pipe lines 154 and 155 are directed toward the pump piston / cylinder unit part a ′. It is extended. The third operation pipe line 154 is branched and connected to the rod side of the second operation cylinder 117 for suction and the head side of the second operation cylinder 118 for discharge. Similarly, the fourth operation circuit 155 also extends toward the pump piston / cylinder unit a ′ and branches to the head side of the second operation cylinder 117 for suction and the rod side of the second operation cylinder 118 for discharge. Connected to and respectively. Then, the second operation cylinder 11 for discharge of the fourth operation circuit 155
A second variable throttle valve 181 with a check valve is provided in the vicinity of 8.

One conduit between the first two-way switching valve 140 and the second two-way switching valve 141 and between the third two-way switching valve 150 and the fourth two-way switching valve 151. In this embodiment, hydraulic pressure sources P and P'which discharge equal amounts to these pipelines are provided in one of the pipelines, and a tank T is provided in the other pipeline.
T'is respectively connected.

Next, the operation of the above embodiment will be described. First, the state before entering the state shown in FIG. 2, that is, the first driving piston 121 is in the pulling stroke and the second driving piston 131 is in the pushing stroke, will be described. The pressure oil supplied from the hydraulic pressure source P is applied to the first operation pipeline 144 from the port U of the second directional control valve 141. On the other hand, since the second operation pipe line 145 is connected to the tank T, no pressure is generated. Therefore, the pressure oil from the first operation pipe 144 is
Although not shown in the drawing, the pressure is reduced to a predetermined value by a pressure reducing valve or the like, and the pressure is supplied to the rod side of the first operating cylinder 107 for suction and the head side of the first operating cylinder 108 for discharge, respectively. The first opening / closing valve 104 is the first suction port 10
9 is opened, and the first on-off valve 106 for discharge is the first discharge port 10
5 is closed.

On the other hand, pressure oil is also supplied from the port Y of the fourth two-way switching valve 151 to the fourth operation pipe line 155, but since the third operation pipe line 154 is connected to the tank T ', No pressure is created. Therefore, the fourth operation line 155
Although not shown in the figure, the pressure oil from is supplied to the head side of the second operation cylinder 117 for suction and the rod side of the second operation cylinder 118 for discharge after being depressurized to a predetermined value by a pressure reducing valve or the like. , The second on-off valve 114 for suction is the second suction port 1
19 is closed, and the second on-off valve 116 for discharge is the second discharge port 1
Open fifteen.

The driving pressure oil from the hydraulic power source P is discharged from the port Q of the first two-way switching valve 140 to the second driving pipe line 143 and supplied to the rod side of the first driving cylinder 120. On the other hand, since the first drive line 142 is short-circuited to the tank T, no pressure is generated on the head side of the driving first cylinder 120. Therefore, the first drive piston 121
Indicates a rightward pulling stroke in the figure. Pump piston / cylinder unit a'which is directly connected to this
The first pump piston 102 is also in the pulling stroke, and the conveyed object to be pumped next is sucked into the first pump cylinder 101 from the first suction port 109. The driving pressure oil from the hydraulic pressure source P ′ is discharged from the port S of the third two-way switching valve 150 to the third driving circuit 152, and the second driving cylinder 13
It is supplied to the head side of 0. On the other hand, the fourth drive circuit 153
Is short-circuited to the tank T ′, so that no pressure is generated on the rod side of the second drive cylinder 130. Therefore, the second drive piston 131 moves to the left in the drawing to be in the push stroke, and the second pump piston 112 of the pump piston / cylinder unit a ′ directly connected thereto is also in the push stroke, and the second pump cylinder The conveyed product in 111 is pressure-fed from the common discharge pipe 110 through the second discharge port 115.

Since the first driving cylinder 120 has the first piston rod 122, the volume thereof is small, and the head side of the second driving cylinder 120 and the rod side of the first driving cylinder 130 are equal to each other. When the pressure oil is supplied to the amount, the pulling stroke speed of the first drive piston 121 becomes
Greater than the push stroke speed of the second drive piston 131,
During the pushing stroke of the second driving piston 131, the pulling stroke of the first driving piston 121 is completed.

The pushing stroke of the second driving piston 131 advances, and as shown in the figure, the second pilot valve 133
After passing through, the pilot pressure is generated in the line 171, and this pressure is applied to the port 163 of the second two-way switching valve 141.
, The spool is pushed, and the flow path of the second two-way switching valve 141 is switched. As a result, pressure oil is applied to the head side of the first operation cylinder 107 for suction from the second operation pipe line 145, and the first opening / closing valve 104 for suction closes the first suction port 109. Discharge first operating cylinder 108
Is also supplied to the rod side of the first opening / closing valve 106 is opened,
Since it is supplied via the first variable throttle valve 180 with a check valve, the opening speed of the first opening / closing valve 106 for discharge is delayed with time.

At the same time, the pilot pressure in the line 171 is also applied to the port 161 of the first two-way switching valve 140,
Similarly, the spool is pushed and the first two-way switching valve 14 is pushed.
The flow path of 0 is also switched, pressure oil is added to the head side of the first drive cylinder 120 via the first drive pipe 142, and the first drive piston 121 enters the pushing stroke. Since the first on-off valve 106 for discharge does not fully open the first discharge port 105 for a predetermined time, a predetermined pressure is generated in the first pump cylinder 101. When the second driving piston 131 is further pushed and reaches the left end, the fourth pilot valve 134 is brought into conduction, a pilot pressure is generated in the line 173, and the ports 165 and 167 of the third and fourth two-way switching valves 150 and 151. Applied to. As a result, the spools of these valves 150 and 151 are pushed and the third and fourth two-way switching valves 150 and 151 are switched. Therefore, pressure is applied to the head side of the second operation cylinder 118 for discharge, the second opening / closing valve 116 for discharge closes the second discharge port 115, and the second operation cylinder 11 for suction is provided.
Pressure is also applied to the rod side of 7, and the second on-off valve 11 for suction is used.
4 opens the second suction port 119. On the other hand, the fourth drive circuit 15
Since the hydraulic power source P ′ is connected to 3, and the third drive circuit 152 is short-circuited to the tank T ′, the second drive piston 131 is in the pulling stroke. Then, the second pump cylinder 111 sucks the conveyed object to be pumped next from the second suction port 119.

In the above state, the first drive piston 121
Is a push stroke, and when this push stroke progresses and the first drive piston 121 passes through the first pilot valve 123,
As described above, the first pilot valve 123 becomes conductive,
Pilot pressure is generated in the line 172 and is applied to the ports 164 and 166 of the third and fourth two-way switching valves 150 and 151, and these switching valves 150 and 151 are switched. As a result, a pressure is generated in the fourth operation pipe line 155, which is applied to the head side of the second operation cylinder 117 for suction, and the second on-off valve 114 for suction closes the second suction port 119 and the second suction valve 119. Since it is supplied to the operation cylinder 118 via the second throttle valve 181 having a check valve, the second opening / closing valve 116 for discharging opens the second discharging port 115 with a time lag. At the same time, pressure oil is supplied from the third two-way switching valve 150 to the third drive circuit 152, and the second drive piston 131 is in the push stroke. First
When the driving piston 121 further moves to the left and reaches the end, the third pilot valve 124 is brought into conduction, and a pilot pressure is generated in the line 170. Therefore, pilot pressure is applied to the ports 160 and 162 of the first and second two-way switching valves 140 and 141, and the two-way switching valves 140 and 14
1 is in the illustrated state, and the pressure oil is the first drive cylinder 1
Since it is supplied to the rod side of 20, the first driving piston 121 is in the pulling stroke. On the other hand, pressure is generated in the first operation pipe line 144, and the first opening / closing valve 104 for suction is connected to the first suction port 10
9 is opened, and the first on-off valve 106 for discharge is the first discharge port 10
Close 5 The transported object is the first pump cylinder 10
It is sucked into 1.

Thereafter, the above operation is alternately repeated,
The conveyed product is pressure-fed from the discharge pipe 110 of the pump piston / cylinder unit a '. The relationship between the discharge pressure from each pump piston / cylinder unit and the stroke of the driving piston is shown in FIG. When the second driving piston 131 passes through the second pilot valve 133, that is, at the point before the second driving piston 131 finishes the pushing stroke, the first driving piston 121 pushes as shown by the chain line. First stroke valve 10 for entering the stroke and for discharging
Since No. 6 opens with a delay, the discharge pressure in the first pump cylinder 101 increases, and it approaches the point B and fully opens. That is, the second driving piston 131 is fully opened before entering the pulling stroke. Therefore, the pulsation of the discharge pressure is small. First, second
The drive switching timing of the drive pistons 121 and 131,
By adjusting the opening / closing timing of the on-off valves 106 and 116 for discharge, a reciprocating double-row positive displacement pump without pulsation can be obtained.

Although not shown in the drawing, the first and second operation pipe lines 144 and 145 are used to change the direction in which the conveyed product is pumped.
Two-way switching valves are provided in the third and fourth operation lines 154 and 155, respectively, and the positions of these valves are changed. Then, the first to fourth two-way switching valves 140, 1
Although the positions of 41, 150 and 151 do not change, the first and second operation pipe lines 144 and 145 and the third and fourth operation pipe lines 144 and 145 are not changed.
The reverse pressure oil described above acts on the operation pipelines 154 and 155. That is, the pressure oil of the hydraulic pressure source P ′ is reversely supplied to the first and second operation cylinders 107 and 117 for suction and the first and second operation cylinders 108 and 118 for discharge, and the first and second operation cylinders 118 and 118 for suction are supplied. The on-off valves 104 and 114 and the first and second on-off valves 106 and 116 for discharge are also opened and closed in reverse. Therefore, the conveyed product is sucked from the discharge pipe 110 and pressure-fed from the first and second suction ports 109 and 119.

As described above, when the conveyed object is pressure-fed, the first and second pump pistons 102 and 112 reciprocate, and the first and second couplings 191 and 192 of the pistons 102 and 112 move to the first and second proximity switches 63. , 63 '. First, second
The proximity switches 63 and 63 'detect this and the signal is input to the control device 60. The control device 60 has the first and second
The number of reciprocations of the pump pistons 102 and 112 per unit time, that is, the number of strokes, is counted and stored. In this embodiment, the filling efficiency η is the first and the third.
Pressure in the drive lines 142, 152 of the pressure gauges 66, 6
6'is measured and calculated by the controller 60 in the same manner as in the first embodiment. That is, since the present embodiment is a pressure feeding system with less pulsation, as shown in (a) and (b) of FIG. 5, before the point Y _{0 at} which the second driving piston 131 ends the pushing stroke. At the point X ₁ of the first drive piston 12
1 enters the push stroke. Similarly, the first drive piston 12
The second drive piston 131 enters the push stroke at a point Y ₁ before the point X _{2 at} which 1 finishes the push stroke. Since the same operation is repeated thereafter, the pressure gauges 66 and 66 'detect the waveforms shown in (a) and (b) of FIG. 5, respectively. These waveforms are substantially the same as the pressure waveform of the conveyed product. As is clear from these figures, the initial period t ₂ in each stroke t, t, is an ineffective pressure period that only compresses, for example, the air sucked in the suction process but does not contribute to the pumping of the conveyed product, The pressure is low. Then, after the period t ₂ , the period t ₁ of the predetermined pressure effective for the pressure feeding is reached. Therefore, the charging efficiencies η ′, η ″, at the individual strokes t, t, are obtained by t1 / t, as in the first embodiment. Then, the control device 60 calculates, for example, the charging efficiency η by averaging the charging efficiencies η ′ and η ″ in each stroke, and stores them.

The specific gravity ρ of the conveyed product is measured by the densitometer 68 and input to the control device 60 via the signal line 69. The control device 60 stores the average specific gravity ρ of the conveyed product within a predetermined time.
The volumes V of the first and second pump cylinders 101 and 111,
V is input to the control device 60 and stored. The control device 60 uses the formula Q = V × St × η × ρ × 60 to calculate the first and second pump cylinders based on the filling efficiency η, the specific gravity ρ of the conveyed object, and the stroke number St obtained as described above. An hourly pressure feed amount T / H discharged from 101 and 111 is calculated. Then, the control device 60 outputs the pressure feed amount to an output device such as a display or a printer.

According to the present embodiment, the packing efficiency η of the conveyed product
Is obtained from the respective pressure gauges 66, 66 ′ provided in the first and third drive lines 142, 152, the filling efficiency η can be simply calculated from the ratio between the stroke period t and the effective pressure period t1. When applied to a reciprocating double-row positive displacement pump with less pulsation, a further effect can be obtained. Of course, the charging efficiency η of the conveyed product can be obtained from the area of the pressure waveform, as in the first embodiment. In addition, according to the present embodiment, the packing efficiency η of the conveyed product is such that the first and third drive lines 14 are
Since it is obtained from the pressure waveforms of Nos. 2 and 152, the pressure gauge 6
6 and 66 'are not contaminated with sludge or the like, and there is also an effect that they can be accurately measured over a long period of time.

[0055]

According to the first aspect of the present invention, the pump piston / cylinder unit for transportation is driven by the driving piston / cylinder unit connected to the pump piston / cylinder unit to carry out the transportation. When pumping a conveyed product from the pump piston / cylinder unit of, the filling efficiency of the conveyed product is obtained from the pressure waveform of the conveyed product or the pressure waveform of the piston / cylinder unit for driving. Therefore, it is possible to accurately and easily detect the pressure-feed amount of a highly viscous transported material such as sludge or compressible dehydrated cake from a relatively low-viscosity slurry, which is a unique effect of the present invention. Is obtained. According to the invention described in claim 2, since the specific gravity of the conveyed object is also automatically measured, in addition to the above effect, an effect that the detection of the pressure-feeding amount becomes easier can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic view showing a first embodiment in which the present invention is applied to a reciprocating double-row positive displacement pump.

FIG. 2 is a schematic diagram showing a second embodiment in which the present invention is applied to a reciprocating double-row positive displacement pump with few pulsations.

FIG. 3 is a diagram illustrating an example of a discharge pressure pattern of a conveyed product according to the first embodiment.

FIG. 4 is a diagram showing a relationship between a stroke of a piston and a discharge pressure of a conveyed product according to a second embodiment.

FIG. 5 is a diagram showing a pressure waveform of the second embodiment, in which (a)
FIG. 4 is a diagram illustrating a pressure pattern in a first drive line and (b) in a third drive line.

[Explanation of symbols]

a, a'Pump piston / cylinder unit (transport pump piston / cylinder unit) b, b'Drive piston / cylinder unit (drive piston / cylinder unit) 10,110 Discharge pipe 58, 68
Density meter 53, 53 'First and second proximity switch 63, 63' First and second proximity switch 50, 60 Control device 56, 66,
66 'pressure gauge

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[Procedure amendment]

[Submission date] July 15, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

[0007]

In order to achieve the above object, a pump piston / cylinder unit for transportation is connected to the pump piston / cylinder unit to drive the piston / cylinder. When the product is driven by the unit to pump the product from the pump piston / cylinder unit for carrying, the filling efficiency η of the product is obtained from the pressure waveform of the product or the hydraulic pressure waveform of the driving piston / cylinder unit. Then, the pumping amount is calculated by the following equation. Q = V × St × η × ρ where Q: pumping amount per unit time St: number of strokes per unit time of the pump piston / cylinder unit η: filling efficiency ρ: specific gravity of the conveyed product V: of the conveying cylinder Volume The invention according to claim 2 is the specific gravity ρ of the conveyed product according to claim 1.
Is automatically measured and calculated.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

[0008]

[Function] The pressure oil is supplied to and discharged from the driving piston / cylinder unit, the pump piston / cylinder unit for driving is driven, and the transported object is pressure-fed. At this time, the pressure waveform of the conveyed product discharged from the conveying pump piston / cylinder unit draws a certain pattern. For example, one of the pistons
In terms of per stroke, the pressure is low in the initial stage of the pushing stroke of the piston, which is a so-called ineffective pressure that does not contribute to the pumping, and becomes a predetermined pressure effective for the pumping after a lapse of a predetermined time. From the ineffective pressure and the effective predetermined pressure, the filling efficiency η of the conveyed object in the conveying cylinder is obtained. Alternatively, the driving piston
The pressure waveform of the hydraulic pressure for driving the cylinder unit is
Since the pattern of the pressure waveform of the conveyed product is substantially the same, the filling efficiency η is obtained from the waveform of the driving pressure of the hydraulic pressure of the driving piston / cylinder unit. Then, for example, it is input to the control device. The specific gravity ρ of the conveyed product is measured in advance and input to the control device. The volume V of the transfer cylinder is also input in advance. Then, the control device counts the number of strokes St of the pump piston / cylinder unit per unit time by a signal from, for example, a proximity switch, and calculates the pressure feed amount per unit time by the formula: Q = V × St × η × ρ And output. According to the second aspect of the present invention, the specific gravity of the conveyed product is automatically measured and input to, for example, the control device. Then, the control device similarly calculates the pressure feed amount per unit time by the formula Q = V × St × η × ρ and outputs it.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction content]

Ports D and C of the second two-way switching valve 19B
The main pipelines 26, 26 'are connected to. Main pipeline 2
6'extends toward the pump piston / cylinder unit a and is connected to the cylinder head side of the operating cylinder 8 '. First branch line 27 branched from the main line 26 '
Is connected to the piston rod side of the operating cylinder 8, the second branch conduit 28 is connected to the piston rod side of the operating cylinder 5 ′, and the third branch circuit 29 is connected to the cylinder head side of the operating cylinder 5. Has been done. A pressure reducing valve 46 'with a check valve is installed in the main pipe 26', and flow rate adjusting valves 47, 47 'with a check valve are installed in the first branch pipe 27 and the second branch pipe 28, respectively. There is. Main line 2
From 6 ', a conduit 31' is branched, and this conduit 30 'is connected to the port M of the two-way switching valve 19A via a throttle valve 31'.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

Pilot valves 15 and 16 are provided near both ends of the first drive cylinder 11, respectively, and pilot pipes 37 and 37 'extend from these pilot valves 15 and 16, respectively. 37 is the second 2
The pilot port H of the directional control valve 19B and the pilot pipe 37 'are connected to the pilot port G of the second two-way control valve 19B. More Piro
The conduits 37, 37 'are branched to the pilot pipes 38, 3'.
8 ', respectively .

[Procedure correction 6]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

On the other hand, the driving pressure oil from the hydraulic pressure source P is the first
It is discharged from the port B to the discharge pipe 35 through the two-way switching valve 19A and is supplied to the head side of the first drive cylinder 11. Since the discharge pipe 34 is short-circuited to the tank T,
No pressure is generated on the head side of the second drive cylinder 12. Therefore, the first driving piston 13 moves to the left in the drawing and is in the pushing stroke. The first pump piston 2 of the pump piston / cylinder unit portion a directly connected to this is also in the pushing stroke, and the conveyed product in the first pump cylinder 1 is pressure-fed from the discharge pipe 10. Since the first drive piston 13 of the drive piston / cylinder unit part b moves leftward, the pressure oil in the first drive cylinder 11 is supplied to the rod side of the second drive cylinder 12 via the conduit 40. Second
The driving piston 14 moves to the right. That is, it is a pulling stroke. Therefore, the pump piston / cylinder unit a
The second pump piston 2'also goes to the right, and the next object to be pumped is sucked into the second pump cylinder 1'as indicated by the chain line arrow. The second drive piston 14 of the drive piston / cylinder unit b is the drive cylinder 1
When reaching the right end of 2, the shock is buffered by the action of the cushion valve 18.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Name of item to be corrected] 0024

[Correction method] Change

[Correction content]

When the first driving piston 13 of the driving piston / cylinder unit portion b moves to the left and reaches the end portion, the pilot valve 15 operates as described in the above-mentioned Japanese Patent Application No. 58-60662, Pilot pressure is applied to the port H of the second two-way switching valve 19B via the pilot pipe 37, the spool 22 of the second two-way switching valve 19B is switched, and the hydraulic power source P is connected to the main pipe line 26. Then, the pressure oil depressurized by the check valve-equipped pressure reducing valve 46 is supplied to the operating cylinders 5, 8 ', 5', 8 this time, the valve bodies 4 and 7'are opened, and the valve body 4 ' The valve body 7 is closed. The driving pressure oil from the hydraulic pressure source P is applied to the port K of the first two-way switching valve 19A via the conduit 30 and the other port M.
Since no pressure oil acts on the first two-way switching valve 1
The spool 21 of 9A is also switched, and the pressure oil is discharged from the port A to the discharge pipe 34 through the first two-way switching valve 19A and is supplied to the head side of the second drive cylinder 12 of the drive piston / cylinder unit part b. It Therefore, the second drive piston 14 moves left in the figure, and the second pump piston 2'of the pump piston / cylinder unit a also moves left. Since the pump piston 2 ′ moves to the left, the conveyed product in the second pump cylinder 1 ′ is the discharge pipe 1
It is pumped from 0. Since the second driving piston 14 of the driving piston / cylinder unit part b moves leftward, the pressure oil is supplied to the rod side of the first driving cylinder 11 via the conduit 40, and the first driving piston 13 moves to the right. To go. Therefore, the first pump piston 2 of the pump piston / cylinder unit a also moves to the right, and the conveyed object to be pumped next as described above is sucked into the first pump cylinder 1. Thereafter, the above-described operation is alternately repeated so that the conveyed product is the discharge pipe 1 of the pump piston / cylinder unit a.
It is pumped from 0. When changing the pressure feeding direction, although not shown in the figure, a two-way switching valve is provided in the main pipelines 26, 26 ', and this valve is switched to change the spool position. Then, the valve position of the drive piston / cylinder unit b does not change, but the main line 2
The reverse pressure oil described above acts on 6, 26 ', and the direction of pressure transfer changes.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

The charging efficiency η is calculated by the controller 50. That is, the pressure gauge 56 provided in the discharge pipe 10
Shows the pattern as shown in FIG. 3 because the carrier pressure is measured and input to the control device 50 because the pump is reciprocating. For example, looking at the first stroke A1st of the first pump piston 2,
The time t2 at the beginning of the first stroke A1st is the first time t2.
Although the pump piston 2 has just entered the pushing stroke and the reactive pressure has not reached the predetermined discharge pressure, it becomes the predetermined pressure effective for pressure feeding after the time t2. Therefore , the first
From the ratio of the pressing process time t of the stroke A1St and the time t1 when the predetermined pressure is reached , the first stroke A1st is determined.
Kicking Takashifun efficiency eta _'(1) is wherein charging efficiency _eta' can be obtained by (1) = t1 / t × 100. For example, the first stroke A1
In st, the reactive pressure time t2 is extremely short, so the effective time t1 for pressure feeding is the pressing step time t of the first stroke A1st.
And the packing efficiency η ′ is approximately 95 to 100%.
Also, the second stroke A2st of the first pump piston 2
The time t2 when the predetermined discharge pressure is not reached is about 1/3 of the pressing step time t of the second stroke A2st , so t1 becomes 2/3, and the second stroke A2st
The filling efficiency η ′ _{(2) in the above} is t1 / t × 100 = 2 /
3t ÷ t × 100 = 66%. Hereinafter , the charging efficiencies η ′ ₍₃₎ , ₍₄₎ , and the like are calculated in the same manner. The waveforms of the first, second, and strokes obtained by the second pump piston 2'are shown by B1st, B2st ,.
The filling efficiency η ″ ₍₁₎ , ₍₂₎ , and the like are obtained from this waveform in the same manner. The control device 50 determines the filling efficiency from the pattern of the pressure waveform for each stroke thus obtained.
Ratio η ′ ₍₁₎ , ₍₃₎ , ₍₄₎ ,, η ″ ₍₁₎ ,
_{(2) and} are calculated, and the average filling efficiency η of a predetermined number of strokes is calculated and stored. Then, the pressure-feeding amount T / H per hour is calculated by the formula Q = V × St × η × ρ × 60 and output to an output device such as a display or a printer. Since the filling efficiency η is proportional to the pressure waveform of the conveyed product, it can be calculated from the ratio with the set area by integrating the area of the waveform.

[Procedure Amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction content]

The following table shows the measured values when the sludge was pressure-fed by the method of the above embodiment using the pressure gauge 56 and the actually measured values. In the above table, the unit time for measuring the pumping amount according to this example is 30 minutes, and the specific gravity is the value actually measured by the density meter 58 shown in FIG. Further, the manually measured value in the table is a value obtained by directly weighing the amount discharged from the discharge pipe 10, and the specific gravity is a value obtained by actually measuring the discharged material to be discharged. As is clear from the above table, according to the present embodiment, the pressure feed amount can be detected with an accuracy of 95% or more.

[Procedure Amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0036

[Correction method] Change

[Correction content]

Pump piston / cylinder unit a '
And a drive piston / cylinder unit b'is provided with a water chamber box 62 for cooling and buffering these unit a ', b'. The first and second couplings 191 and 192 are the water chamber box 6
2 and the pump cylinders 101 and 111 reciprocate, but the first and second couplings 1 are provided outside the water chamber box 62.
The reciprocating motions of 91 and 192, that is, the pump pistons 102 and 112 of the pump piston / cylinder unit a '.
First and second proximity switches 6 that detect the number of strokes
3, 63 'are provided. These proximity switches 6
3, 63 'are signal lines 65, 65' on the control device 60.
It is connected to the.

[Procedure Amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0043

[Correction method] Change

[Correction content]

Next, the operation of the above embodiment will be described. First, the state before entering the state shown in FIG. 2, that is, the first driving piston 121 is in the pulling stroke and the second driving piston 131 is in the pushing stroke, will be described. The pressure oil supplied from the hydraulic power source P is the port of the second directional control valve 141.
It is applied from V to the first operation line 144. On the other hand, since the second operation pipe line 145 is connected to the tank T, no pressure is generated. Therefore, the pressure oil from the first operation pipe 144 is
Although not shown in the drawing, the pressure is reduced to a predetermined value by a pressure reducing valve or the like, and the pressure is supplied to the rod side of the first operating cylinder 107 for suction and the head side of the first operating cylinder 108 for discharge, respectively. The first opening / closing valve 104 is the first suction port 10
9 is opened, and the first on-off valve 106 for discharge is the first discharge port 10
5 is closed.

[Procedure Amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0047

[Correction method] Change

[Correction content]

The pushing stroke of the second driving piston 131 advances, and as shown in the figure, the second pilot valve 133
After passing through, the pilot pressure is generated in the line 171, and this pressure is applied to the port 163 of the second two-way switching valve 141.
, The spool is pushed, and the flow path of the second two-way switching valve 141 is switched. As a result, pressure oil is applied to the head side of the first operation cylinder 107 for suction from the second operation pipe line 145, and the first opening / closing valve 104 for suction closes the first suction port 109. It is also supplied to the rod side of the first operation cylinder 108 for discharge, and the first opening / closing valve 106 opens, but since it is supplied via the first variable throttle valve 180 with a check valve, the first opening / closing for discharge is performed. The opening speed of the valve 106 is delayed in time.

[Procedure Amendment 13]

[Document name to be amended] Statement

[Correction target item name] 0050

[Correction method] Change

[Correction content]

Thereafter, the above operation is alternately repeated,
The conveyed product is pressure-fed from the discharge pipe 110 of the pump piston / cylinder unit a '. Relationship between piston stroke for driving the discharge pressure from each pump piston-cylinder unit is shown in Figure 4. Second drive piston 1
When the point A before 31 finishes the pushing stroke, that is, the second driving piston 131 passes through the second pilot valve 133,
The first drive piston 121 enters the push stroke as shown by the dashed line and the first on-off valve 106 for discharge
Is opened with a delay, the discharge pressure in the first pump cylinder 101 is increased, and the valve fully approaches the point B. That is, the second driving piston 131 is fully opened before entering the pulling stroke. Therefore , the pulsation of the discharge pressure of the conveyed product in the discharge pipe 110 is small. First and second drive pistons 121,
The drive switching timing of 131, the on-off valve 106 for discharge,
By adjusting the opening / closing timing of 116, a reciprocating double-row positive displacement pump without pulsation can be obtained.

[Procedure Amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0052

[Correction method] Change

[Correction content]

As described above, when the conveyed object is pressure-fed, the first and second pump pistons 102 and 112 reciprocate, and the first and second couplings 191 and 192 of the pistons 102 and 112 move to the first and second proximity switches 63. , 63 '. First, second
The proximity switches 63 and 63 'detect this and the signal is input to the control device 60. The control device 60 has the first and second
The number of reciprocations of the pump pistons 102 and 112 per unit time, that is, the number of strokes, is counted and stored. In this embodiment, the filling efficiency η is the first and the third.
Pressure in the drive lines 142, 152 of the pressure gauges 66, 6
6'is measured and calculated by the controller 60 in the same manner as in the first embodiment. That is, since the present embodiment is a pressure feeding system with less pulsation , the first drive line 14 is shown in FIG.
2 and (b) the pressure path in the third drive line 152.
The piston 1 for the second drive, as shown by the turn
At the point X ₁ before the point Y ₀ where 31 ends the pushing stroke,
The driving piston 121 enters the push stroke. Similarly, at the point Y ₁ before the point X _{2 at} which the first driving piston 121 finishes the pushing stroke, the second driving piston 131 enters the pushing stroke. Since the same operation is repeated thereafter, the pressure gauge 66,
66 'detects the waveforms shown in (a) and (b) of FIG. 5, respectively. These waveforms are substantially the same as the pressure waveform of the conveyed product. As is clear from these figures, the initial time t ₂ in the pushing process time t, t of each stroke is not effective in only pumping the air sucked in the suction process and not contributing to the pumping of the conveyed object. During the pressure period, the pressure is low. And past the time t _2, it is time t1 of a valid place pressure on the feed. Therefore, the charging efficiency η ′, η ″, in each stroke is calculated by t1 / t, as in the first embodiment.
Is the charging efficiency η ′, η ″,
Are averaged to calculate the filling efficiency η and stored.

[Procedure Amendment 15]

[Document name to be amended] Statement

[Correction target item name] 0054

[Correction method] Change

[Correction content]

According to the present embodiment, the packing efficiency η of the conveyed product
But since it is obtained from each of the pressure gauge 66, 66 'provided in the drive line 142, 152 of the first and third, the charging efficiency eta, at time t and the effective pressure of about押工 stroke
Ki out be easily obtained from the ratio of the between t1, when applied to the pulsation less reciprocating Dofuku string type displacement pump is obtained further effects. Needless to say, the packing efficiency η of the conveyed product is the same in the first drive line 142 and the third drive line 152 as in the first embodiment .
It can also be obtained from the area of the pressure waveform of the hydraulic pressure. Further, according to the present embodiment, since the packing efficiency η of the conveyed product is obtained from the pressure waveforms of the first and third drive pipe lines 142 and 152,
Despite the fact that the filling efficiency η of the transported material such as sludge is measured, the pressure gauges 66 and 66 ′ are not contaminated with sludge or the like, and there is an effect that the pressure gauges 66 and 66 ′ can be accurately measured for a long period of time.

[Procedure Amendment 16]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 4]

[Figure 3]

[Figure 5]

Claims (2)

[Claims] 1. A conveying pump piston / cylinder unit is driven by a driving piston / cylinder unit connected to the pump piston / cylinder unit to convey a conveyed object from the conveying pump piston / cylinder unit. When pressure is fed, the filling efficiency η of the conveyed object is obtained from the pressure waveform of the conveyed object or the pressure waveform of the driving piston / cylinder unit,
A method for detecting a pumping amount of a reciprocating type positive displacement pump, characterized in that the pumping amount is calculated by the following formula. Q = V × St × η × ρ where Q: pumping amount per unit time St: number of strokes per unit time of the pump piston / cylinder unit η: filling efficiency ρ: specific gravity of the conveyed product V: of the conveying cylinder volume 2. A reciprocating displacement pump pressure detection method for automatically measuring and calculating the specific gravity ρ of a conveyed product according to claim 1.