SU1384822A1 - Piston pump - Google Patents

Abstract

The invention makes it possible to improve the quality of washing of the cylinder-piston group when pumping abrasive-containing liquids. The main piston (P) 4 is rigidly connected with the rod 5 having an annular stop. Additional P 8 is spring-loaded relative to P 4 and mounted on the rod with the possibility of contact with its abutment and the end wall 3 of cylinder 1 to form a suction valve in the contact zone with this wall. The inner forming annular channel 14 for communicating the working chamber (K) 6 to K 9 of variable volume for flushing fluid is formed by the outer surface of the valve of the discharge valve 12, the length of channel 14 is longer than the stroke length P 8. At the initial moment of operation between K 6 and the rod To 7, a pressure differential occurs, as a result of which the washing liquid from K 7 fills K 9, from where it passes through channel 14 to K 6, preventing cavitation from occurring in it and protecting the surface of the cylinder in the zone of channel 14 from the pumped liquid and abrasive particles contained therein. When P 4 takes its extreme position, there will be a separation of K 9 from the source of washing liquid and its displacement in Kb. 3 hp f-ly, 3 ill. SS (L

Description

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The invention relates to a pump-building system, in particular, to piston pumps for pumping abrasive liquids.

The aim of the invention is to improve the quality of washing of the cylindrical piston group when pumping abrasive fluids.

Figure 1 shows a diagram of a cylinder-piston group of a pump; Fig. 2 shows a variant of the cylinder-piston group of the pump; on fig.Z - the same, another option.

The piston pump contains a cylinder I with end walls 2 and 3, in which piston 4 and rod 5 are rigidly interconnected, which form piston working 6 and rod 7 of the chamber, an additional piston 8 that is movably mounted relative to the main piston 4 on the rod. 5 to form a variable volume chamber 9 for the flushing fluid. The additional piston 8 is spring-loaded with the spring 10 relative to the main piston 4, and the rod 5 is provided with an annular stop 11 for restricting the movement of the additional piston 8. The chamber

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a channel 20 in the body wall 3, corresponding to the protrusions 18 and 19, annular concentric grooves 21 and 22 (FIG. 3), moreover, when combining the additional piston 8 and the stop 11 of the rod 5, the length of the protrusion 18 of the additional shaft 8 is longer than the length of the protrusion 19 of the stop 11 of the rod 5.

The shutter of the discharge valve 12 can be installed on the tension spring 23 () or on the guide rods x 24 (Fig. 3), and the length of the annular channel 14 can be longer than the code length of the additional piston 8. Working chamber 6 provided with inlet 25 and outlet 26 valves, and the main piston may be equipped with a sealing element 27.

The pump works as follows.

At the start of movement of the main piston 4 from the leftmost position to the right, the additional piston 8 with spring 5 is pressed against the stop 11 of the rod 5, and the pressure in the rod chamber 7 due to its decrease and resistance to the movement of fluid in the channel 15 somewhat rises. Due to inertia

The variable volume 9 is in communication with the operation of the inlet valve 25 and enlarging the chamber with the help of the discharge valve 12, the channel 13 in the main piston 4 and the annular channel 14, the outer part of which is the inner surface of the cylinder 1, and the internal generator can the area of the outer surface of the main piston 4 (Fig.) or the outer surface of the gate of the discharge valve 12 (Figures 2 and 3). The rod chamber 7 communicates with the source of flushing fluid via channel 15, and the variable volume chamber 9 communicates with the rod chamber 7 via channel 16 in the additional piston 8 and the suction valve formed when the end face of the additional piston 8 contacts the end wall 3 of cylinder 1 , for which sealing face 17 (figures 1 and 2) is made on the end surface of the additional piston 8. .

The additional piston 8 and the stop 11 of the rod 5 on the side facing the end wall 3 of the rod chamber 7 are provided with concentrically arranged annular protrusions I8 and 19, respectively, and on the very end wall 3 are communicated between

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The volume of the working chamber 6 pressure in the latter drops and a pressure differential occurs between chambers 6 and 7, as a result of which the flushing fluid from the rod chamber 7 and channel 16 fills the chamber 9 of variable volume, from where through channel 13 and non-return valve 12 The annular channel 14 enters the working chamber 6, preventing the occurrence of cavitation in the working chamber 6, and protects the surface of the cylinder 1 in the zone of the annular channel 14 from the pumped liquid and abrasive particles contained in it. Upon further movement of the main piston 4 to the right, the intake valve 25 opens and the pumped fluid fills the working chamber 6. When the main piston 4 approaches the right extreme position, the additional piston 8 contacts the end wall 3 of the cylinder, separates the variable volume chamber 9 from the source of flushing fluid, thus fulfilling the function of the suction valve. Stopping the additional piston 8 and the continued movement of the main piston 4 towards the end wall 3 of the cylinder 1 results in

decreasing the volume of the variable volume chamber 9, increasing the pressure therein and displacing the washing liquid through the discharge valve 12 into the annular channel 14 and the working chamber 6, while the inlet valve 25 is closed with an overpressure in the working chamber 6.

When the main piston 4 moves to the left, the pressure increase in the working chamber 6 causes the discharge valve 12 to close, and the additional piston 8 is kept in contact with the end wall by the spring IO.

In the embodiment of the pump shown in Fig. 3, when the main piston 4 approaches to the extreme right position, the annular protrusion 18 of the additional piston 8 enters the annular groove 21 and then through the channel 16 into the variable volume chamber 9. After the entrance of the annular protrusion 1 9 of the stop 1 1 of the rod 5 into the annular groove 22, the pressure in the annular grooves 21 and 22 of the channel 20 increases and acts on the additional piston 8, displacing it to the main piston 4, thereby reducing the volume of the chamber 9 volume, which leads to leakage of flushing fluid from the chamber 9, as indicated above.

Claims (4)

1. Piston pump with valve distribution, containing a cylinder with 0 5 Q 0 five 0 five butt-end walls, in which a piston and a piston are connected interconnected with the formation of a piston-working and rod-shaped chambers, a piston, an additional piston mounted relative to the main piston to form a variable-volume chamber for flushing fluid communicated with the working chamber by means of an annular channel, the outer part of which is the inner surface of the cylinder of the discharge valve and the channel in the main piston, and with the rod chamber communicated with the source of washing liquid channel in the additional piston and the suction valve, which is due to the fact that, in order to improve the quality of the washing of the cylinder-piston group when pumping abrasive-containing liquids, the main piston and the rod are rigidly interconnected, the rod is provided with an annular stop, and the additional the piston is spring-loaded relative to the main piston and mounted on the rod with the possibility of contact with its annular stop and the cylinder end wall to form in the contact zone with this wall of the suction valve. 2. Pump pop. 1, which differs from the fact that the inner annular channel for communicating the working chamber with the variable volume chamber for the washing liquid is formed by the outer surface of the discharge valve of the discharge valve. 3. Pump PPP.1 and 2, characterized in that the length of the annular channel is made longer than the stroke length of the additional piston. 4. Pump according to claims 1-3, characterized in that the additional piston and the rod stop on the side facing the end wall of the chamber chamber are provided with concentrically arranged annular projections, and the corresponding walls communicating with each other in the body wall are made on the end wall. the protrusions have annular concentric grooves, and the length of the protrusion of the additional piston is longer than the length of the protrusion of the rod stop when the additional piston and the rod stop are combined. 12 1 1 W 1S 17 17 11 3 / / / / uchach lcc 25 6 24 7 27 73 8 IS 77 7 L . 25 72 GZ if 10 3 1 18 fie.Z fug. 2 15