GB2039603A

GB2039603A - Device for controlling the flow of cement concrete or similar material to and from a pump

Info

Publication number: GB2039603A
Application number: GB7944498A
Authority: GB
Original assignee: Wibau GmbH; WIBAU INDUSTRIE und VERWALTUNG GmbH
Current assignee: Wibau GmbH; WIBAU INDUSTRIE und VERWALTUNG GmbH
Priority date: 1978-12-27
Filing date: 1979-12-28
Publication date: 1980-08-13
Also published as: IT7927982A0; JPS5591777A; DE2856254A1; IT7923360V0

Abstract

The flow of concrete and like material to and from parallel cylinders of a pump is controlled by a distributor pipe 7 which swivels about a horizontal axis at its upper end where it is provided with a swivel coupling. A hopper 34 which receives the concrete has a concave bottom with openings 6 connected to respective pump cylinders. The swivelling distributor pipe is aligned with these openings in alternation so that one cylinder draws concrete from the hopper while the other delivers concrete into the distributor pipe. The lower end of the distributor pipe is guided by a fixed guide 27 on the hopper bottom. The upper end of the pipe is horizontal and mounted in a swivel coupling in the hopper wall, and a drive lever is attached to this part of the pipe outside the hopper. <IMAGE>

Description

SPECIFICATION Device for controlling the flow of cement concrete or similar material to and from a pump The present invention relates to a device for cantroll- ing the flow of cement concrete, or similar masses to or from a pump which has two pistons guided in cylinders arranged side by side and operating in alternation.

German Patent Specification 2104191 discloses such a device, in which concrete or the like is supplied via a hopper, the bottom of which acts as a distributor plate with two openings connected to respective pump cylinders. In the hopper is an S-shaped distributor pipe with its ends vertical, the upper end being coupled to a vertical discharge pipe by a swivel coupling, and the lower end being swivelled, about the vertical axis of the upper end, into line with the said openings in alternation, in synhcronism with the pump pistons, so that at any time the pump cylinder that is acting in suction is connected to the opening not covered by the distributor pipe and therefore draws concrete out of the hopper, whereas the other pump cylinder, acting in compression, is connected via the associated opening and the distributor pipe to the discharge pipe.The swivel coupling is inside the hopper, and the distributor pipe is swivelled by a vertical drive shaft extending through the bottom of the hopper.

The distance between openings leading to the pump cylinders as a rule corresponds, forconstruc- tional reasons, to the necessary distance between the cylinders, that is to say it is kept as small as possible; conversely, however, to avoid dead zones outside the intake range of the openings in the distributor plate, a relatively large swivel angle must be provided if the swivel drive is located on the inside, in order to meet the requirement for an intake range which is virtually free of dead zones, and this in turn is identical with a small base area of the hopper.

This large swivel angle, however, requires a large driving force and hence high power of the swivel drive for the distributor pipe, as the swivelling has to be carried out rapidly; this leads to extensive wear in the swivel coupling between the discharge pipe and the distributor pipe, and in the separate guide bearing, attached to the hopper, for the swivel mounting of the distributor pipe.

Furthermore, in conjunction with the large swivel angle and the provision of a large force, the actual swivel drive lever cannot be formed in an appropriate length, since space is available only to a limited extent for the arrangement of the swivel drive, which is to be provided parallel to the plane of the hopper bottom.

It is therefore the object of the invention to provide a device wherein the requisite swivel angle of the distributor pipe iS considerably reduced.

According to the invention, there is provided a device for controlling the flow of cement, concrete, or like material to and from a reciprocating pump with two alternately operating cylinders side by side, which device comorises a vessel for-said material, at least part of the vessel bottom being a distributor plate which is concave and has two openings for connection to respective pump cylinders, a distribu tor pipe with an upright arm in the vessel and with a swivel coupling at its upper end whereby the said arm can swivel about a generally horizontal axis to bring the lower end of the pipe into alignment with said openings in alternation, and a drive connection for swivelling the distributor pipe about the said axis.

In a preferred embodiment of the invention, there is provided a device for controlling the flow of cement concrete or similar masses to and from a pump which has two pistons guided in cylinders and arranged parallel to one another, in which device the masses fed via a vessel are alternately delivered via a distributor into a discharge line by the cylinder which is delivering at the time, a distributor plate leading to the delivery cylinders is part of the vessel bottom, and one end of a distributor pipe, formed with ends offset parallel to the axis, is connected by a swivel joint to the discharge pipe, and the other end of the pipe is directed towards the opening, leading to the cylinder which is delivering at the time, of the distributor plate and thus connects, in a location within the vessel, the delivery cylinder to the discharge line, characterised in that the swivel plane of a first arm of the distributor pipe, which is mounted at the vessel, ends in a swivel coupling, and is of angular design. is arranged at an offset of about 90" to the passages in a plane which forms the distributor plate and is curved towards the other arm, corresponding to the swivel radius; that the end, facing the distributor plate and formed like a flange corresponding to the latter, of the first arm of the distributor pipe is held by a guide profile which partially surrounds this end flange and is resilient in the axial direction of the distributor pipe but is supported rigidly relative to the axis of the swivel coupling against the direction of delivery; and that, on the said other arm, joined to the swivel coupling, of the distributor pipe, a lever is provided for swivelling the first arm, facing the distributor plate of the distributor pipe.

One result of such a design of a device for controlling the material flow is that, if the bearing for the upper arm of the distributor pipe on a wall of the vessel is arranged and fixed in a suitable manner, that is to say at a sufficient height, the resulting swivel angle is substantially smaller, as compared with the state of the art.

In the design of known devices the distance, to be designated as the base line, between the centres of the openings, and the distance of this base line from the swivel axis, arranged centrally thereto, have a ratio of 1:1, which in turn means a swivel angle of about 60 . Because of the need to maintain continuous flow in the vessel, that is to say completely satisfactory emptying, it is not possible to increase the distance of the swivel axis from the base line.

However, in a device according to the invention, the ratio of the distance between the openings in the distributor plate, that is to say the base line, to the distance of the swivel axis from the base line can readily be improved to 1:4, while maintaining an appropriate construction of the vessel, and this entails a reduction of the swivel angle from about 60 to 150. In turn, this means a reduction in wearby about 75% and a corresponding lowering of the power of the swivel drive.

Since, due to the continually repeated changeover of the distributor from one to the other delivery cylinder under a delivery pressure which ranges up to 120 bars, the construction of concrete pumps cannot be regarded as absolutely-"rigid", andpul- sating shocks leading to vibrations must be ex7 pected, provision is made not only for a mounting of the distributor pipe on a vessel wall, which mounting is independent of the swivel coupling itself, but furthermore provision is made for a guide, which is rigidly supported in the axial direction of the swivel coupling, opposite to the direction of delivery, to resist the delivery pressure, but is resilient in the axial direction of the upright arm of the distributor pipe, facing the distributor plate.This guiding of the swivelling distributor pipe largely takes into account the properties, that is to say the detrimentai vibra- tions, of the concrete pump and ensures a safe seal of the distributor pipe relative to the vessel with readjustment for a long time. The arm leading out of the vessel, at a large distance from the plane of the delivery cylinders and parallel tithe latter, makes it possible to provide a longer change-over lever than in the known devices, virtually unhindered by other constructional features.

To guide the distributor pipe it is proposed that the guide profile for the distributor pipe is of angular design, the arm, which points in the direction of delivery, of the guide profile being the abutment for resilient sleeves which consist of an elastic material and in each of which a conical member likewise abutting on the guide profile engages, and a tightening bolt connection going in each case through the guide-profile, the conical member, the sleeve and the distributor plate. Preferably, supports bear against the guide profile, over its length or locally, on an outersurfacewhich faces away from the angled recess and is approximately parallel to the swivel plane of the distributor pipe.

This design of the guide for the distributor pipe ensures both reliable, resilient guiding in the axial direction of the distributor pipe and completely adequate support against the actual delivery direction in the swivel coupling.

In this connection, it is also envisaged that the end, formed like a flange and matching the distributor plate, of the upright first arm of the distributor pipe has an approximately square two rectangular outline.

In this way, a large seating length of the flange-like end in the guide profile is achieved.

To enable the distributor pipe to be adjusted in the direction of the distributor plate, it is advisable to guide the arm, which at a vessel wall points perpendicular to the swivel plane of the swivel coupling, of the distributor pipe, by means of a bearintg which is adjustable in its position relative to the vessel wall.This ensures a reliable basic setting and, over a long operating period, scope for readjustments necessitated by wear. For the design of such a bearing, it-isenvisaged that enlarged pas sages for the distributor pipe and the fixing bolts are provided in the vessel structure and that the carrier flange of uthe bearing isfixed, in.the adjusted position of the bearing, by several, preferably three, screws which are located on a ring surrounding the carrier flange at a distance and fixed to the vessel wall and wbich point substantially radially towards the periphery of the carrier flange.

Preferably, the part of the swivel coupling that surrounds a flange of the discharge pipe is formed .on the end of the upper arm, directed to the delivery pipe, of the distributor pipe. Thus, the major part of the swivel coupling remains on the pump, it is merely necessary to provide a standard flange design ofthe discharge pipes which are to be connected, and it is advantageous as a rule to joln the discharge pipe to a stationary connector, that is to say a connector fixed to the pump.

The invention will be explained in more detail by reference to the accompanying drawings af one embodiment.

In the drawings: Figure 1 shows a section on the line C-D of Figure 2, perpendicular to the swivel plane of the distributor pipe, through a concretetsupply vessel, Figure 2 showS a section through the vessel on line A-B of Figure 1, parallel to the swivel plane of the distributor pipe, and Figure 3 shows on a larger scale a detail of Figure 1 namely the guide profile for the distributor Concrete-pump cylinders, which are not shown, are connected via pipe elbows 1 to a distributor plate 3 which at least partially forms the bottom of a hopper 34 for supplying concrete. In some cases, to provide adequate space between the cylinders, the elbows 1 are arranged at an angle 2 opening outwards.

The distributor plate 3 is curved, corresponding to the swivel radius 4 of a pivotable distributor pipe 7, and has two passages 6 located symmetrically to the central position of the pipe 7, corresponding to swivel angle 5. The pipe is of an inverted L-shape, with a horizontal upper arm 8 guided, perpendicular to the swivel plane 18; through the hopper wall 17, in a a swivel mounting in the latter; the arm 8 is eonnected by a 90 bend piece to a vertical arm 9 guided pehRendicular to the plane of the distributor plate 3.At its lower end, facing the plate 3, the arm 9 has a square flange 10 haying a surface which faces and is curved corresponding to the distributor plate 3flat the outlet end, that is to say on the arm 8, is formed a coupling socket 11. A swivel coupling 16 is formed by this coupling socket 11 together with a flange 12 of-a discharge pipe 13, seals 14 and a coupling cover 16. A swivel lever 19 actuated by a swivel drive 20 !s connected to the arm 8, parallel to the swivel plane 18 and outside the hopper 34.

The arm 8 pastes through the vessel wall 17 via an opening 21 which has a diameter larger than that of the arm. The swivel bearing 22 faces this opening.

The bouts, guided ina close fit through the mounting flange 23-of the swivel bearing 22, extend through appropriately arranged bores of larger diameter in the hopper wall 17 so that, for alignment, the bearing is displaceable and readjustable within narrow limits. Mounted in a pipe ring 24 fixed to the wall 17 and surrounding the flange 23 at a distance, three lockable radial screws 25 point against the periphery of the flange 23, and the swivel bearing 22 is thus fixed in its adjusted position.

To guide the lower end flange 10 of the distributor pipe, an arcuate L-section guide member 27 is provided, curved corresponding to the swivel radius 4 less its distance from the distributor plate, one limb 35 of the guide member projects over the square flange 10, and the other limb 28 abuts on one side of the flange 10.

Conical parts 29, located at intervais over the length of the guide member 27, the resilient sieeves 30 extending over the conical parts, resilientiy engage the limb 28 of the guide member 27. The guide member is resiliently fixed in its position by corresponding adjustment of bolts 31 which extend through the distributor plate 3, the conical parts 29 with the surrounding sleeves 30, and the limb 28.

To the rear, against the actual direction of delivery of the material in the swivel coupling, the guide member 27 is held by support elements 32 which are rigidly joined to the distributor plate 3 or the hopper wall.

To reduce wear, the flange 10 may be covered with a replaceable wear gasket 33.

In operation, the pump cylinders operate in alternation and the distributor pipe swivels in synchronism, so that at any time one cylinder is drawing concrete from the hopper while the other is discharging concrete into the distributor pipe which is aligned with the corresponding opening 6. A substantially constant delivery of concrete is thus obtained.

Claims

1. A device for controlling the flow of cement, concrete or like material to and from a reciprocating pump with two alternately operating cylinders side by side, which device comprises a vessel for said material, at least part of the vessel bottom being a distributor plate which is concave and has two openings for connection to respective pump cylinders, a distributor pipe with an upright arm in the vessel and with a swivel coupling at its upper end whereby the said arm can swivel about a generally horizontal axis to bring the lower end of the pipe into alignment with said openings in alternation, and a drive connection for swivelling the distributor pipe about the said axis.

2. A device as claimed in claim 1 in which the drive connection is outside the vessel.

3. A device as claimed in claim 1 or 2 including guiding means engaging the lower end region of the said upright arm for maintaining alignment of the said lower end with the said openings.

4. A device for controlling the flow of cement concrete or similar masses to and from a pump which has two pistons guided in cylinders and arranged parallel to one another, in which device the masses fed via a vessel are alternately delivered via a distributor into a discharge line by the cylinder which is delivering at the time, a distributor plate leading to the delivery cylinders is part of the vessel bottom, and one end of a distributor pipe, formed with ends offset parallel to the axis, is connected by a swivel joint to the discharge pipe, and the other end of the pipe is directed towards the opening, leading to the cylinder which is delivering at the time, of the distributor plate and thus connects, in a location within the vessel, the delivery cylinder to the discharge line, characterised in that the swivel plane of a first arm of the distributor pipe, which is mounted at the vessel, ends in a swivel coupling, and is of angular design, is arranged at an offset of about 90" to the passages in a plane which forms the distributor plate and is curved towards the other arm, corresponding to the swivel radius; that the end, facing the distributor plate and formed like a flange corresponding to the latter, of the first arm of the distributor pipe is held by a guide profile which partially surrounds this end flange and is resilient in the axial direction of the distributor pipe but is supported rigidly relative to the axis of the swivel coupling against the direction of delivery; and that, on the said other arm, joined to the swivel coupling, of the distributor pipe, a lever is provided for swivelling the first arm, facing the distributor plate of the distributor pipe.

5. A device according to claim 4, characterised in that the guide profile for the distributor pipe is of angular design, an arm, which points in the direction of delivery, of the guide profile being the abutment for resilient sleeves which consist of an elastic material and in each of which a conical member likewise abutting on the guide profile engages, and a tightening bolt connection going in each case through the guide profile, the conical member, the sleeve and the distributor plate.

6. A device according to claim 5, characterised in that supports bear against the guide profile of angular design over its length or sectionally on an outer surface which faces away from the angled recess and is approximately parallel to the swivel plane of the said first arm of the distributor pipe.

7. A device according to any of claims 4 to 6, characterised in that the end, formed like a flange and corresponding to the distributor plate, of the first arm of the distributor pipe has an approximately square to rectangular outline.

8. A device according to any of claims 4 to 7, characterised in that the said other arm, which at the vessel wall extends perpendicular to the swivel plane of the swivel coupling, of the distributor pipe is guided in a bearing which is adjustable in its position relative to the vessel wall.

9. A device according to claim 8, characterised in that, to adjust the bearing, enlarged passages for the distributor pipe and the bearing fixing bolts are provided in the vessel structure and that a carrier flange of the bearing is fixed in position by several, preferably three, locking screws which are located on a ring surrounding the carrier flange at a distance and fixed to the vessel wall and which point substantially radially towards the periphery of the carrier flange.

10. A device according to any of claims 4 to 9, characterised in that the part, which surrounds a flange of the discharge pipe, of the swivel coupling is formed on the end of the said other arm of the distributor pipe.

11. A device for controlling the flow of material, substantiaily as herein described with reference to the accompanying drawings.