JPH04265478A - Pump for viscous material - Google Patents

Abstract

PURPOSE: To provide a pump for viscous substance which can be produced by arranging branch ducts as a compact and lightweight structure at a low cost, and can be used usefully for the pressure feed of viscous substance even at a narrow mounting place. CONSTITUTION: A slide material 6 is oscillated around the axis of a central duct 9, and the positions of a pair of pressure feed cylinders 2, 3 are fixed by branch ducts 7, 8 connected through the central duct 9. Control sealing surfaces 18, 20 are formed at the inner-wall 19 of a slide material housing 21 in which viscous substance is fed, and the apertures 28, 29 of the respective feed cylinders 2, 3 are formed at the housing 21. The respective ducts 7, 8 are sealed while releasing the suction side feed cylinder for respective control sealings 18, 20, and the identical pressure is generated at the branch ducts of equal length, thus it is possible to conduct delivery action and suction action alternately.

Description

[Detailed description of the invention]

0001

FIELD OF INDUSTRIAL APPLICATION The present invention relates to a pump for viscous substances having a pair of pressure cylinders, preferably disposed parallel to each other, which alternately perform a discharge action and a suction action, the sliding member being located in a central duct. For each pair of pressure-feeding cylinders that are oscillated about their axis, one branch duct connects each cylinder on the discharge side to a fixed-position pressure-feeding pipe via a central duct connected to this pipe; At the same time, the second branch duct of the sliding member is sealed against each one control sealing surface assigned to each branching duct, while releasing the pressure cylinder on the suction side, and the control sealing surface are formed in the inner wall of the sliding member housing into which the viscous substance flows, the sliding member housing is formed with an opening for each one of the pressure cylinders, and branch ducts of the same length are provided with the same pressure. This invention relates to a pump for viscous substances.

0002

BACKGROUND OF THE INVENTION The viscous material pumped by the pump according to the invention can have a variety of compositions, and usually the viscous material pumped is itself a mixture of various substances. This is generally a mushy material with a relatively high moisture content, such as sludge, mortar, etc. The invention particularly relates to concrete pumps used to pump liquid mixtures, usually consisting of sand, cement aggregate and water, often over considerable distances and through elevation differences.

The pump for viscous substances according to the invention operates in conjunction with pressure cylinders, whose reciprocating pistons fill the cylinders with viscous substance, often from a prefill container via a slide member housing, during the return movement. However, during forward movement, the sliding member forces the viscous substance into the pressure feeding pipe that is fixed in position. According to the invention, two pressure cylinders always work together, one pressure cylinder is filled and the other cylinder is discharged into the pressure pipe, so that the suction and discharge strokes of both pistons overlap. ing. Therefore, the present invention is also applicable to two or more pairs of cylinders if temporally closer overlap of the pumping strokes is desired.

The control of the discharge and suction flows is carried out by means of a sliding member with one branch duct for each pumping cylinder, which, during the discharge stroke, connects the cylinder to a central duct leading to the discharge pipe. and opens an opening in the cylinder having the suction piston, into which the viscous substance to be suctioned flows through the sliding member. If the pump for viscous substances has two or more pairs of pumping cylinders, it is usually necessary to provide a separate branch duct for each auxiliary pumping cylinder. A preferred embodiment of the invention, configured as a two-cylinder viscous pump, will now be described.

However, in all embodiments of the pump for viscous substances according to the invention, the openings of the branch ducts of the sliding members communicating with the respective cylinders are sealed against the wall of the sliding member housing, so that the suction of viscous substances is prevented. Sometimes it is necessary to prevent the viscous substance stream under pressure of the delivery piston from partially overflowing into the suction cylinder as a whole and to prevent the viscous substance from flowing back into the prefill container during delivery. The specific sequence of movement of the sliding member must therefore be synchronized with the movement of the piston in the cylinder, but this can be done by reversing the sequence of the sliding member connected to the prefilling vessel from the piping for pumping the viscous substance. Like the possibility offered for many pumps for viscous substances of this type, discharging into the housing is not a subject of the present invention.

Pumps for viscous substances having the general characteristics described above have a simple structure, especially when the pumping distance and height are large, even though their operating form and operational requirements during discharge are complicated. There is a general requirement to ensure a pumping of viscous substances that is simple and free from undue disturbances due to failure or wear of functionally important components, and in particular as continuous as possible. The basic problem of the present invention lies in this point.

A pump for viscous substances of the type mentioned at the outset has a sliding member in the form of a V-shaped forked tube, the branching ducts forming a fork-like claw, and the longitudinal axis of the central tube pointing towards the pump. German Published Publication No. 27216, which forms a geometrical axis around which the sliding member rotates when activated.
No. 78, it is publicly known. In the embodiment of a two-cylinder viscous substance pump, the prongs of the tube result from the distance of the pumping cylinders which are arranged parallel to each other or aligned. Forming the sliding member as a fork-shaped tube means that
It is also suitable for the case of a four-cylinder pump for viscous substances, in which the pairs of pressure cylinders are aligned and two pressure cylinders are required to be in the discharge state at the same time. The free ends of the branch ducts are curved, independent of the number of pumping cylinders, so that when configured as a two-cylinder viscous substance pump, each opening seals one of the two control sealing surfaces. However, the other opening forms a connection with the pumping cylinder. Therefore, the control sheet
The surface is flat and attached to the bottom of the prefill container.

[0008] The operating demands of the sliding member during the dispensing operation are relatively large and become even greater as the pumping distance and pumping height increase. This is due to the reaction forces that occur in the sliding member during pumping of the viscous substance. Both openings of the branch duct are subjected to pumping pressure during each stroke of the delivery piston. Due to the pumping pressure and the inner surface of the branching ducts, a reaction force is generated in both branch ducts, by which the sliding member is pushed up from the control sealing surface and from the opening of the pumping cylinder. This reaction force is
It is partially compensated by the forces due to the inner surface of the central duct and the pumping line pressure. This is the force that must be overcome during pumping. The resulting large residual force creates a gap at the opening of the branch duct, which is unacceptable in order to prevent the aforementioned short-circuiting of the discharge flow. This presupposes excessively heavy bearings of the shaft driving the sliding member and of the oscillating sliding member. It is also necessary to avoid premature wear of this important component.

[0009]

SUMMARY OF THE INVENTION It is an object of the invention to avoid these disadvantages and to achieve an advantageous effect on the problem.

0010

Means for Solving the Problems The above problems are solved by the structure of claim 1. Further features of the invention are set out in the claims below.

According to the present invention, as shown in claim 1,
Due to the alignment of the branch ducts, their openings substantially overlap each other in their vertical projection. Therefore, most of the reaction forces are canceled out, and only the reaction forces from non-overlapping parts of the partial surfaces remain. This is compensated for by moving the cylinder openings closer together, which is preferable due to space requirements, but the effect on compensating for reaction forces is not great.

Due to the alignment of the branch ducts, the lengths of the two partial ducts are equal, so that it is possible to have a cylindrical control sealing surface during the oscillating movement of the sliding member. In that case, the tip of the branch duct can be straight,
This is advantageous from a hydrodynamic technique and in particular simplifies the sealing. This is because the gap between the opening of the branch duct and the control sealing surface associated therewith, ie in said opening, does not change during the oscillating movement.

The basic advantage of the present invention is that by eliminating heavy bearings in the housing of the sliding member and its drive shaft, a previously unattainable lightweight construction is achieved, and the sliding in the sliding member housing is reduced. The goal is to achieve highly reliable and failure-resistant sealing of components. Therefore, the pump for viscous substances according to the present invention not only can be provided at a low cost as a particularly compact structure, but also can be usefully used for pumping viscous substances even in narrow installation locations.

According to a preferred embodiment of the present invention, the branch ducts can be precisely aligned, so that the sliding member can be constructed to be free from reaction forces. The duct in the sliding member therefore has a precise T-shape.

According to the features of claim 3, the cylindrical shape of the control sealing surface is expanded to the shape of the entire slide member housing. This results in a centrosymmetric housing shape which is advantageous from a manufacturing standpoint. This is a major operational advantage. In the known sliding member having a tubular shape used in this embodiment of the invention, a rear gate is formed at the rear of each branch duct during the rocking movement due to the viscosity of the viscous material, as claimed in the claims. In the configuration shown in 3, this is not the case. This is because the free space of the housing before and after each branch duct remains equal and thus corresponds exactly to the amount of viscous material forced out by the preceding branch duct. Therefore, no rear gate is formed in the sliding member housing.
No decompression of viscous substances occurs. That is, this reduced pressure must first be relieved by the delivery piston in the delivery cylinder before the delivery flow is started. In that case,
Discharge becomes uneven, causing problems. According to the present invention, this problem is resolved.

According to the feature of claim 4, it is not necessary to discharge the viscous substance into the slide member housing. That is,
The sliding member has the shape of a solid cylinder, which shape can be achieved by the action of the invention without excessively increasing the weight of the sliding member.

Next, the present invention will be explained in more detail based on the drawings.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIGS. 3 and 4, the pump for viscous substances, designated as a whole by 1, is designed as a two-cylinder piston pump. Thereby, two pressure cylinders 2, 3 are obtained which are arranged parallel to each other and alternately carry out a discharge action and a suction action.

The pistons (not shown) of the pressure cylinders 2, 3 are actuated in opposite phases to each other in the hydraulic drive cylinders 4, 5 via piston rods of the pistons (also not shown). The sliding member 6 (FIG. 1) performs a rocking movement during operation of the pump 1 and comprises two branch ducts and a central duct 9. This rocking movement is carried out by the shaft 10 about the geometrical axis of the central duct 9. The shaft 10 is
It is located in an axial-radial bearing 11 and passes through the bottom body 12 of the sliding member 6. At the end position of the sliding member's swing, one of the branch ducts 7, 8 (branch duct 7 in the embodiment of FIG. 1) is connected to one of the two bent pipes 14, 15 (
In the embodiment of FIG. 1, the pressure cylinder 2
, thereby establishing communication with the central duct 9. The center duct 9 has a centering sleeve joint 16 at the tip formed as a curved pipe 17 of a discharge pipe (not shown).
are arranged so as to be rotatable.

In this position of the sliding member 6, the second branch duct 8 of the sliding member 6 seals against the control sealing surface 18 while at the same time opening the suction-side pressure cylinder or curved pipe 15. will be stopped. The control sealing surface 18 along with the second control sealing surface 20 of the sliding member housing 21 is connected to the inner wall 19.
formed on top. In the embodiment shown, this sealing is achieved via an axially movable tube ring 22 which is attached to the inner wall of the housing 21.
The inner end of the tube ring 22 is guided on the outer surface of the branch duct 7 and is actually oriented inwardly on four sides. It is sealed by a packing 24 that is partially embedded.

The slide housing 21 feeds the viscous substance to be pumped via a prefill container 25 . The prefill container 25 has a cylindrical compartment 26 and a conical funnel part 2.
7 and the small diameter end of the funnel portion 27 is aligned with the upper end of the cylindrical slide member housing 21.

Corresponding to the operation of the viscous substance pump described below, the housing 21 itself has two openings 28, 2
It has 9. The openings 28, 29 opened by one of the branch ducts 7, 8 allow the viscous substance contained in the prefill container 25 to flow through the slide member housing 21 to the cylinder 3 or 2 on the suction side. do. The opening diameters of the branch ducts 7 and 8, that is, the pipe ring 22, are the same. Further, the branch ducts 7 and 8 also have the same length.

In the embodiment shown in FIGS. 1 to 4, the branch ducts 7, 8 are precisely aligned. Branch duct 7,
8 contains an exact right angle with the central duct 9, so T
The straight lateral legs are formed by two branching ducts, and together with the vertical legs, which include the central duct and are located in the plane of the lateral legs and include a right angle between them. , forming the aforementioned T-shape. In order to obtain an optimal shape for the flow of the ducts 7, 8 and 9, which extend into each other, inside the T-shaped sliding element 6, the tube faces 31, 32 of the branch ducts 7, 8 are vertically It has a shape that converges to a tip 33 along the central axis of the leg.

In the embodiment shown in FIG. 5, in contrast to the previous embodiments, the transverse legs 34 extend at an acute angle to one side from the T-shaped surface of the slide. Therefore, the housing 21
The openings 28, 29 of are brought closer together and the distance of the parallel cylinders 2, 3 from each other is reduced.

In the embodiment of FIGS. 1 to 5 the sliding member is tubular, whereas in the embodiment of FIG. 6 this is not the case. In this example, the sliding member is in the form of a solid cylinder 35, and the branch ducts 7, 8 and at least a portion of the central duct 9 that is continuous with the branch ducts 7, 8 are bored inside this solid cylinder. This solid cylinder is guided with rotational play in the cylindrical housing 21. The perforations for the ducts 7, 8 and 9 pass through the center of the housing 21, as shown in FIG. The solid cylinder also has a peripheral notch 36 as a suction path (indicated by arrow 37) along the cylindrical housing 21, which notch allows the slime material from the prefilled container 25 to flow into the cylinder on the suction side. Its function is to allow it to be filled.

In all the embodiments described above, the sliding member housing 21 is designed as a hollow cylinder, the axis of which coincides with the axis of the central duct 9, the cylindrical wall of which has branch ducts 7. , 8 control seal surfaces 18, 2
The aforementioned openings 28, 29 of the cylinders 2, 3 to 0 are formed. The upper opening of the hollow cylinder (indicated by 39 in FIG. 3) coincides with the lower opening of the prefill container 25. The opening facing this is closed except for the part through which the shaft passes.

According to the above configuration, as shown in FIG.
Identical cavities 40, 41 are formed on both sides of the tubular sliding member. The rocking movement of the sliding member occurs over an angle of approximately 50° on both sides. In this case, the amount of viscous material forced into the cavities 40, 41 from the preceding branch duct is equal to the quantity forced into the cavities 40, 41 from the subsequent branch duct. Therefore, no reduction in pressure occurs in the viscous material present in each cylinder housing.

Although the present invention has been described with reference to specific embodiments thereof, the present invention can be implemented with various other modifications, and the specific configurations described above are merely illustrative and do not limit the present invention.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a first embodiment of the invention, with parts not necessary for understanding the invention removed.

FIG. 2 is a top view of the embodiment of FIG. 1;

FIG. 3 is a side view of a viscous pump according to the invention incorporating the configuration of FIGS. 1 and 2;

FIG. 4 is a top view of the pump of FIG. 3;

FIG. 5 is a top view corresponding to FIG. 2 showing a modified embodiment of the invention;

FIG. 6 is a top view corresponding to FIG. 5 showing yet another modified embodiment of the invention.

[Explanation of symbols]

2, 3 Cylinder 6 Sliding member 7, 8 Branch duct 9 Center duct 18, 20 Control seal surface

Claims (4)

[Claims] [Claim 1] Performing a discharge action and a suction action alternately,
A pump for viscous substances having pairs of delivery cylinders, preferably arranged parallel to each other, the sliding member being swung about the axis of the central duct, and for each pair of delivery cylinders one branch duct for each delivery. The side cylinders are connected to a fixed pressure supply pipe via a central duct connected to this pipe, and at the same time the second branch ducts of the sliding member are connected to the respective one branch duct assigned to each branch duct. The pressure cylinder on the suction side is sealed while releasing the pressure cylinder against a control seal surface, and the control seal surface is formed on the inner wall of the sliding member housing into which the viscous substance flows, and the sliding member The housing is formed with an opening for each one of the pressure cylinders, so that the branch ducts (7, 8) are essentially aligned and centered in such a way that branch ducts of the same length produce the same pressure. The control sealing surface (18) of the sliding member housing (21),
, 20) is curved into a cylindrical shape. 2. Pump for viscous substances according to claim 1, characterized in that the branch ducts (7, 8) form lateral legs and together with the central duct (9) form a T-shape. 3. The sliding member housing (21) forms a hollow cylinder, the axis of which coincides with the axis of the central duct (9), the cylindrical wall (19) of the hollow cylinder forming a hollow cylinder (2, 3) and has control sealing surfaces (18, 20) inside for the branch ducts (7, 8), the upper opening (39) of the hollow cylinder being the pre-filled container. 3. A pump for viscous substances according to claim 1 or 2, characterized in that the opening is opened at the sliding member housing (25), and the opening on the opposite side of the sliding member housing (21) is closed. 4. The sliding member housing (6) is formed as a solid cylinder, which solid cylinder is guided with pivoting play in the cylindrical wall (19) of the sliding member housing and is connected to the branch duct (
7, 8) and a central cutout for the central duct (9) and a peripheral cutout (36) as a suction path along the cylindrical wall (19) of the slide member housing (21). , 2 or 3. The viscous substance pump according to any one of .