JPH0571451U - Reciprocating positive displacement pump coupling device - Google Patents

Abstract

(57) [Summary] [Object] To provide a coupling device for a reciprocating positive displacement pump which is easy to assemble and remove by hand and is also applicable to a cylinder having a small diameter. A coupling device 101 for connecting a piston rod 3 of a pump piston / cylinder unit and a piston rod 22 of a drive piston / cylinder unit.
Is divided into two connecting members 103, 10 divided in the longitudinal direction.
4 and the inside of both ends of these coupling members are
A recess 10 into which the joint portion 3'of the piston rod of the pump piston / cylinder unit and the joint portion 22 'of the piston rod of the drive piston / cylinder unit are respectively fitted.
7 and 108, and two grooves 109 and 110 for mounting snap rings are formed on the outer peripheral portion.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a reciprocating positive displacement pump coupling device, and more particularly, to a reciprocating positive displacement pump coupling unit that connects a piston rod of a pump piston / cylinder unit and a piston rod of a driving piston / cylinder unit. It concerns a ring device.

[0002]

[Prior Art]

 For example, a reciprocating type positive displacement pump for pumping highly viscous substances such as sludge is well known in the art without mentioning a literature name, and generally, a pump piston / cylinder unit and a driving piston / driving unit for driving this unit are generally known. It is roughly configured by a cylinder unit and a hydraulic circuit that supplies and discharges pressure oil to and from the drive piston / cylinder unit. A typical conventional example is shown in FIG. That is, a pump piston 201 is provided in the pump cylinder 200 so as to be reciprocally movable, a discharge valve 202 is provided at a tip end portion thereof, and a suction valve 203 is provided at a side thereof. Similarly, a drive piston 205 is also provided reciprocally in the drive cylinder 204, and pressure oil is supplied to and discharged from the head side and rod side of the piston 205 through pipe lines 206 and 207.

Piston rods 208 and 209 extend from the pump piston 201 and the drive piston 205 so as to approach each other, and flanges 210 and 211 are fixed to the tip ends thereof, respectively. The coupling 212 interposed between the flange 210 and the flange 211 also has flanges 213 and 214 at both ends. Then, these flanges 210 to 214 are coupled by a plurality of bolts 215, 216, and the rod 208 of the pump piston 201 and the rod 209 of the drive piston 205 are integrated. Although not shown in the figure, instead of connecting the flanges 210 to 214 with a plurality of bolts 215, 216, a coupling that holds the outer peripheral portion of the flanges 210 to 214 together with a band is also known. ing.

[0004]

[Problems to be solved by the device]

 In the above conventional reciprocating displacement pump as well, since the rod 208 of the pump piston 201 and the rod 209 of the drive piston 205 are connected by the coupling 212, pressure is applied from the pipe lines 206 and 207 to the cylinder of the drive piston / cylinder unit. When the oil is supplied / discharged, the drive piston 205 is reciprocally driven, and the discharge valve 202 and the suction valve 203 are opened / closed in response to the reciprocal driving, the conveyed product is sucked from the suction valve 203 into the pump cylinder 200, and It is discharged from the discharge valve 202. It has a high discharge pressure and can process liquids with relatively low viscosity to highly viscous viscous substances. However, since there is a problem with the coupling 212 and the flanges 210 and 211 of the piston rods 208 and 209 and the flanges 213 and 214 of the coupling 212 are connected by a plurality of bolts 215 and 216, it is easy to assemble and remove. There is a drawback that it takes time. Further, since the flanges 210 to 214 are tightened by the bolts, the dimension of the flanges 210 to 214 becomes large, and there is a drawback that the pump cylinder 200 cannot be used if its diameter is small. The coupling device having a structure in which the outer peripheral portion of the flanges 210 to 214 is clamped with a pressing band has the same drawback. Therefore, an object of the present invention is to provide a coupling device for a reciprocating positive displacement pump which is compact and easy to assemble and remove and can be applied to a cylinder having a small diameter.

[0005]

[Means for solving]

 In order to achieve the above object, the present invention provides that when a piston rod of a pump piston / cylinder unit and a piston rod of a driving piston / cylinder unit are coupled by a coupling device and the driving piston / cylinder unit is driven, In a reciprocating type positive displacement pump in which a transported object is pumped from the pump piston / cylinder unit, the coupling device is composed of a plurality of coupling members divided in a longitudinal direction, and the coupling members are coupled to each other. Inside both ends of the member, there are formed recesses into which the joint portion of the piston rod of the pump piston / cylinder unit and the joint portion of the piston rod of the drive piston / cylinder unit are respectively fitted, and the outer circumference. The part has a plurality of grooves for mounting snap rings.

[0006]

[Action]

 Since the present invention is configured as described above, the joint portion of the piston rod of the pump piston / cylinder unit and the joint portion of the piston rod of the drive piston / cylinder unit are separated into both end portions of the joint member. Fit the snap ring into the groove for installing the snap ring so that it is surrounded by the concave part. Then, the piston rod of the pump piston / cylinder unit is connected to the piston rod of the drive piston / cylinder unit via the coupling device. Therefore, when the drive piston / cylinder unit is reciprocally driven, the pump piston / cylinder unit is also reciprocally driven, and by this reciprocating drive, the conveyed product is sucked into the pump piston / cylinder unit and is pressure-fed.

[0007]

【Example】

 An embodiment of the present invention will be described below. FIG. 1 shows an example in which the coupling device 101 is located in the cylinder 1 of the pump piston / cylinder unit. The piston of the pump piston / cylinder unit is shown at 2 with its rod 3, whereas the drive piston / cylinder unit is shown only at its rod 22. The rods 3 and 22 are connected by a coupling device 101.

As shown in FIG. 1B, the coupling device 101 has a first joint member 103 in the present embodiment, which is a columnar body of a predetermined length divided into two in the longitudinal direction. And the second joint member 104. Grooves 105 and 106 into which the piston rods 3 and 22 are inserted at the time of assembly are axially formed inside both ends of these joint members 103 and 104, and the tip end portions of these grooves 105 and 106 are formed. Similarly, semicircular recesses 107 and 108 into which the joint portions 3'and 22 'of the piston rods 3 and 22 are fitted at the time of assembly are formed. Ring-shaped grooves 109 and 110 for mounting snap rings are provided at positions corresponding to the recesses 107 and 108 on the outer peripheral portions of the first and second joint members 103 and 104.

Next, the operation will be described. The first and second joint members 103 and 104 are put together, and the joint portions 3 ′ and 22 ′ of the piston rods 3 and 22 are fitted into the semicircular recesses 107 and 108. Then, snap rings 112 and 113 are attached to the ring-shaped grooves 109 and 110. Then, the piston rods 3 and 22 are coupled by the coupling device 101. The combined state is shown in FIG. It is obvious that the snap rings 112 and 113 can be removed and disassembled. As described above, according to the present embodiment, the piston rods 3 and 22 can be easily coupled by simply mounting the snap rings 112 and 113. Further, since the snap rings 112 and 113 are used for fastening the coupling device 101, the size of the coupling device 101 is small and it can be applied to a small diameter cylinder.

Next, a practical example of a reciprocating return-type positive displacement pump using the coupling device of the above embodiment will be described. 2 is a plan view thereof, and FIG. 3 is a side view thereof. Referring to these figures, the reciprocating reversing type positive displacement pump according to the present embodiment shows a pump piston / cylinder unit A and a drive unit. It is easily understood that the piston / cylinder unit B and the three-way ball valves 4 and 14 provided in the pump piston / cylinder unit A are roughly configured. Further, it is easily understood by those skilled in the art that the piston rod of the pump piston / cylinder unit A and the piston rod of the drive piston / cylinder unit B are coupled by the coupling devices 101 and 102. At first glance, referring to the drawings, it is also understood that the entire pump is supported by the bracket 92 and the box 91 on the pedestal 90. The box 91 is called a water chamber, and is filled with water to cool and lubricate the reciprocating piston.

As shown in FIG. 4, the pump piston / cylinder unit A is composed of a pair of first and second cylinders 1 and 11. One end of each of the first and second cylinders 1 and 11 is open to the side wall of the box 91 and the other end is open, and is fixed to the bracket 92 by a flange near the opening. There is. First and second pistons 2 and 12 are reciprocally provided in the first and second cylinders 1 and 11, and the first and second rods 3 and 13 of these pistons are respectively provided with a joint 101, The first and second piston rods 22 and 32 of the drive piston / cylinder unit B are coupled via 102, respectively. The first and second three-way ball valves 4 and 14 are commercial products and have a three-way flange. Then, these flanges are attached to the flanges near the openings of the first and second cylinders 1 and 11, the flange of the bifurcated discharge pipe 5 and the flange of the supply pipe 16, respectively. The bifurcated discharge pipe 5 serves as a single common discharge port 10 and is appropriately connected to a secondary pipe or the like. Further, one relatively large flange 7 is attached to the supply pipe 16 rising in the figure, and although not shown in the figure on this flange 7, for example, a hopper for accommodating a conveyed product is fixed. It has become. A commercially available intermediate trunnion hydraulic cylinder is used as the first operating cylinder 8 for operating the first three-way ball valve 4, and is supported by a bracket 93 so as to be swingable. Similarly, the second operating cylinder 18 for operating the second three-way ball valve 14 is also swingably supported by the bracket 94. The tips of the rods 95 and 96 of the first and second operation cylinders 8 and 18, which are swingably supported in this way, are connected to the first and second three-way ball valves 4 and 4 via pivot members 97 and 98. Pins are coupled to the 14 control levers 99 and 100, respectively.

For the drive piston / cylinder unit B, a commercially available head flange type hydraulic cylinder is modified for the pair of first and second cylinders 20 and 30 for driving, and a box 91 is provided by the front flange. It is fixed. As described above, the first and second piston rods 22 and 32 for driving are connected to the joint portions 3 and 13 of the first and second pistons of the pump piston / cylinder unit portion A through joints. The first and second rods 22 and 32 have a predetermined diameter size or a predetermined volume, at least in the driving first and second cylinders 20 and 30. First and second pilot valves 23 and 33 are respectively provided at predetermined positions in the vicinity of the push stroke ends of the first and second driving cylinders 20 and 30, and the first and second driving cylinders 20 and 30 are provided. Third and fourth pilot valves 24 and 34 are provided at the push stroke end positions of 30, respectively. These pilot valves 23, 33, 24, 34 extract pilot pressure for operating a two-way switching valve, which will be described in detail later. Further, cushion valves 25 and 35 are provided at the pull stroke end positions of the first and second driving cylinders 20 and 30, respectively. The specific configurations and functions of these cushion valves 25 and 35 are as follows. Since it has been described in detail in the above-mentioned Japanese Patent Application No. 58-60662, its explanation is omitted here.

The circuit switching valve portion C includes first and second two-way switching valves 40 and 41 and third and fourth two-way switching valves 50 and 51. The line 60 is used to apply the pilot pressure of the third pilot valve 24 to the port 60 1 of the first two-way switching valve 40. Similarly, the same pilot pressure is applied to the port 62 of the second two-way switching valve 41. The pilot pressure of the second pilot valve 33 is applied to the ports 61 and 63 of the two-way switching valves 40 and 41 by the line 71, and the ports 64 and 66 of the third and fourth two-way switching valves 50 and 51 are operated. A line 72 applies the pilot pressure of the first pilot valve 23, and a line 73 applies the pilot pressure of the fourth pilot valve 34 to the ports 65 and 67. The pump piston / cylinder unit A, the drive piston / cylinder unit B, and the circuit switching valve C are connected to each other by a hydraulic line as described below.

A first drive conduit 42 and a second drive conduit 43 are connected to the ports P and Q of the first two-way switching valve 40, respectively, and these conduits 42 and 43 are used for driving. The first cylinder 20 is connected to the cylinder head side and the rod side, respectively. A third drive conduit 52 and a fourth drive conduit 53 are connected to the ports S and R of the third two-way switching valve 50, respectively, and these conduits 52, 53 are for driving. The second cylinder 30 is connected to the cylinder head side and the rod side, respectively. A first operation pipe line 44 and a second operation pipe line 45 are connected to the ports V and U of the second two-way switching valve 41, respectively. These conduits 44, 45 extend toward the pump piston / cylinder unit A, the first operating conduit 44 is the rod side of the operating cylinder 8, and the second operating conduit 45 is the head side of the operating cylinder 8. Respectively connected to. A first variable throttle valve 80 with a check valve is provided near the operation cylinder 8 of the second operation pipe line 45. Third and fourth operation pipes 54 and 55 are connected to the ports W and Y of the third two-way switching valve 51, and these pipes 54 and 55 extend toward the pump piston / cylinder unit A 1. , The first operation line 54 extends to the rod side of the second operation cylinder 18, and the fourth operation line 55 extends to the pump piston / cylinder unit A in the same manner, and extends to the head side of the operation cylinder 18. It is connected. A second variable throttle valve 81 with a check valve is provided near the second operation cylinder 18 in the fourth operation pipe 55. One pipe between the first two-way switching valve 40 and the second two-way switching valve 41 and one pipe between the third two-way switching valve 50 and the fourth two-way switching valve 51. In this embodiment, hydraulic pressure sources P and P'which discharge equal amounts to these pipelines are connected to the channels, and tanks T and T'are connected to the other pipelines.

Next, the operation of the above embodiment will be described. First, the state before entering the state shown in FIG. 4, that is, the first piston 21 is in the pulling stroke and the second piston 31 is in the pushing stroke, will be described. The pressure oil supplied from the hydraulic pressure source P to the first driving cylinder 20 is also pressure-fed from the port V of the second direction switching valve 41 to the first operation pipe line 44. On the other hand, since the second operation pipe line 45 is connected to the tank T, no pressure is generated. Therefore, although not shown in the figure, the pressure oil from the first operation pipe line 44 is reduced to a predetermined value by a pressure reducing valve or the like and supplied to the rod side of the operation cylinder 8, and the first lever 99 moves the rod 9 to the rod 9 side. Pulled at 5, the first three-way ball valve 4 is switched so that the hopper and the first cylinder 1 communicate with each other. On the other hand, the pressure oil from the hydraulic pressure source P ′ is also supplied from the port Y of the fourth two-way switching valve 51 to the fourth operation pipe line 55, but the third operation pipe line 54 is connected to the tank T ′. Therefore, no pressure is generated. Therefore, although not shown in the figure, the pressure oil from the fourth operation pipe 55 is reduced to a predetermined value by a pressure reducing valve or the like and supplied to the head side of the second operation cylinder 18 so that the second three-way ball Similarly, the valve 14 is switched so that the second cylinder and the discharge port 10 communicate with each other.

On the other hand, the driving pressure oil from the hydraulic power source P is discharged from the port Q of the first two-way switching valve 40 to the second driving pipe line 43 and supplied to the rod side of the first driving cylinder 20. R. On the other hand, since the first drive conduit 42 is short-circuited to the tank T, no pressure is generated on the head side of the first driving cylinder 20. Therefore, the first piston 21 for driving is in the rightward pulling stroke in the figure. The first piston 2 of the pump piston / cylinder unit A directly connected to this also goes into the pulling stroke, and the transported object to be pumped next passes through the hopper, the supply pipe 6 and the first three-way ball valve 4, and then the first cylinder 1 Is sucked in. The driving pressure oil from the hydraulic power source P ′ is discharged from the port S of the third two-way switching valve 50 to the third driving circuit 52 and is supplied to the head side of the second driving cylinder 30. On the other hand, since the fourth drive circuit 53 is short-circuited to the tank T, no pressure is generated on the rod side of the second drive cylinder 30. Therefore, the second piston 31 for driving goes to the left in the figure to be in the pushing stroke, and the second piston 12 of the pump piston / cylinder unit A directly connected thereto is also in the pushing stroke, and the conveyed material in the first cylinder 1 Is pumped from the common discharge port 10 via the second three-way ball valve 14.

Since there is the first driving rod 22 in the first driving cylinder 20, the volume is small, and the head side of the second cylinder and the rod side of the first cylinder are equally distributed. When the pressure oil is supplied, the pulling stroke speed of the first driving piston 21 is higher than the pushing stroke speed of the second driving piston 31, and before the pushing stroke of the second driving piston 31 is completed, The pulling stroke of the driving first piston 21 is completed.

When the pushing stroke of the second driving piston 31 progresses and passes through the second pilot valve 33 as shown in FIG. 4, a pilot pressure is generated in the line 71, and this pressure is generated in the port 63. Is applied to the spool, the spool is pushed, the flow path of the second two-way switching valve 41 is switched, the hydraulic source P is connected to the second operating circuit 45, and the hydraulic fluid is supplied to the head side of the first operating cylinder 8. Since it is supplied via the first variable throttle valve 80 with a stop valve, the switching speed of the first ball valve 4 is delayed with time. At the same time, the pilot pressure generated in the line 71 is also applied to the port 61, the spool is pushed, the flow path of the first two-way switching valve 40 is also switched, and the pressure oil is driven via the first drive pipe line 42. The first piston 21 for driving joins the head side of the first cylinder 20, and enters the pushing stroke. Since the switching of the first ball valve 4 is delayed, a predetermined pressure is generated in the first cylinder 1. When the second driving piston 31 is further pushed and reaches the left end, the fourth pilot valve 34 is brought into conduction, pressure is generated in the line 73, and as a result of being applied to the ports 65 and 67, the spool is pushed and the third pilot valve 34 is pushed. The two-way switching valves 50 and 51 of 4 are switched. Therefore, pressure is applied to the rod side of the second operating cylinder 18, and the second ball valve 14 is switched so that the hopper and the second cylinder 1 communicate with each other. On the other hand, since the hydraulic power source P'is connected to the fourth drive circuit 53 and the third drive circuit 52 is short-circuited to the tank T ', the second piston 31 for driving is in the pulling stroke. The second piston 11 of the pump piston / cylinder unit A, which is directly connected to this, also goes into the pulling stroke, and the conveyed object to be next pressure-fed passes through the hopper, the supply pipe 6 and the second ball valve 14 and then inside the second cylinder 12. Is sucked into.

In the above-mentioned state, the first driving piston 21 is in the pushing stroke, and when this pushing stroke progresses and the first driving piston 21 passes through the first pilot valve 23, the first piston 21 is driven as described above. The 1 pilot valve 23 is turned on, and a pilot pressure is generated in the line 72, which is applied to the ports 64 and 66 of the third and fourth two-way switching valves 50 and 51, and these switching valves 50 and 51 are switched. As a result, pressure is generated in the fourth operation pipe line 55, and hydraulic pressure is supplied to the head side of the second operation cylinder 18. At this time, since the second operation cylinder 18 is supplied via the second throttle valve 81 with a check valve, the second ball valve 14 switches with a time difference. At the same time, pressure oil is supplied from the third two-way switching valve 50 to the third drive circuit 52, and the second piston 31 for driving is in the pushing stroke. When the first piston 21 for driving moves further leftward and reaches the end portion, the third pilot valve 24 is brought into conduction and pressure is generated in the line 70. Therefore, the pilot pressure is applied to the ports 60 and 62 of the first and second two-way switching valves 40 and 41, the two-way switching valves 40 and 41 are in the state shown in the figure, and the pressure oil is transferred to the first cylinder. Since it is supplied to the rod side of 20, the first cylinder 20 is in the pulling stroke. The first piston 1 of the pump piston / cylinder unit A directly connected to this also goes into the pulling stroke, and the conveyed product to be pumped next passes through the hopper, the supply pipe 6 and the first ball valve 4 to the first cylinder. 1 is sucked into.

Thereafter, the above operation is alternately repeated, and the conveyed product is pressure-fed from the discharge port 10 of the pump piston / cylinder unit A. Although the relationship between the discharge pressure from each pump piston / cylinder unit and the stroke of the driving piston is not shown in the figure, the second piston for driving is driven when one driving piston finishes the pushing stroke. When 31 passes through the second pilot valve 33, the other piston P1 enters the push stroke. Since the first on-off valve 6 for discharge is opened with a delay, the discharge pressure in the first cylinder 1 is increased, and eventually it is fully opened. That is, the second driving piston 31 is fully opened before entering the pulling stroke. Therefore, the pulsation of the discharge pressure is small. By adjusting the drive switching timing of the drive piston and the switching timing of the three-way ball valve 4, it is possible to obtain a forward / backward-return type positive displacement pump without pulsation. According to this embodiment, the drive piston / cylinder units 20 and 30 are formed to have the same size, so that the pressure oil is supplied to the cylinder head side during the push stroke of the piston and to the cylinder rod side during the pull stroke at the same rate. Since the drive piston / cylinder unit 20 and 30 are supplied with and discharged with pressure oil, the piston speed of the drive piston / cylinder unit is higher than that of the push stroke. Faster, the other piston can enter the push stroke before one piston finishes the push stroke. That is, the control of the piston is simple, and the hydraulic pressure sources P and P'and the hydraulic circuit are also simple.

When changing the pumping direction of the conveyed product, although not shown in FIG. 4, two directions are provided in the first and second operation pipe lines 44 and 45 and the third and fourth operation pipe lines 54 and 55. Intercalate the switching valves respectively and change the port position of these valves. Then, the positions of the first to fourth two-way switching valves 40, 41, 50, 51 do not change, but the first and second operation pipe lines 44, 45 and the third and fourth operation pipe lines 54, 55. The reverse pressure oil mentioned above acts on this. That is, the pressure oil from the hydraulic power sources P and P'is reversely supplied to the first and second operation cylinders 8 and 18, and the first and second three-way ball valves 4 and 14 are also switched in reverse. Therefore, the conveyed product is sucked from the discharge port 10 and is pressure-fed from the supply pipes 6 and 16 to the hopper through the first and second ball valves 4 and 14.

[0022]

[Effect of the device]

 According to the present invention, the coupling device is composed of a plurality of longitudinally divided coupling members, and a plurality of snap ring mounting grooves are formed on the outer periphery of these coupling members. The effect peculiar to the present invention is obtained in that the piston rod of the pump piston / cylinder unit and the piston rod of the drive piston / cylinder unit can be connected simply by mounting the snap ring in the groove. Further, since the coupling device is composed of a plurality of coupling members and snap rings, the number of parts is small, the structure is simple, and the device is also compact. Therefore, the coupling device according to the present invention can be applied to a cylinder having a small diameter, such as a pump piston / cylinder unit.

[Brief description of drawings]

FIG. 1 is a view showing an embodiment of the present invention, in which (a) is a sectional view, (b) is a drawing showing an embodiment of a coupling device, and an enlarged front view showing the upper half in section. is there.

FIG. 2 is a plan view schematically showing an embodiment of a reciprocating return parallel displacement pump to which the coupling device according to this embodiment is applied.

FIG. 3 is a side view schematically showing the embodiment shown in FIG.

FIG. 4 is a plan view schematically showing an embodiment of the hydraulic drive circuit.

FIG. 5 is a front view showing a conventional example.

[Explanation of symbols]

 1 Cylinder 3,22 Piston rod 3 ', 22' Joint part 101 Coupling device 107,108 Recess 103,104 1st, 2nd joint member 112,113 Snap ring

Claims (1)

[Scope of utility model registration request] 1. A piston rod of a pump piston / cylinder unit and a piston rod of a drive piston / cylinder unit are coupled by a coupling device, and when the drive piston / cylinder unit is driven, the pump piston / cylinder unit is driven. In a reciprocating volumetric pump in which a conveyed object is pumped, the coupling device is composed of a plurality of coupling members divided in the longitudinal direction, and inside both end portions of these coupling members are A recess for fitting the piston rod joint portion of the pump piston / cylinder unit and the piston rod joint portion of the drive piston / cylinder unit respectively is formed, and a plurality of snap rings are mounted on the outer peripheral portion. Reciprocating type positive displacement pump characterized by having grooves formed therein Coupling device.