EP1402181A1

EP1402181A1 - Device for transporting a free-flowing bulk product to be transported

Info

Publication number: EP1402181A1
Application number: EP02745395A
Authority: EP
Inventors: Hellmut Hurr; Gerald Fischer; Frank Pirwass
Original assignee: Putzmeister AG; Putzmeister Werk Maschinenfabrik GmbH
Current assignee: Putzmeister Concrete Pumps GmbH
Priority date: 2001-07-04
Filing date: 2002-06-19
Publication date: 2004-03-31
Anticipated expiration: 2022-06-19
Also published as: DE10131903A1; WO2003004875A1; ES2266526T3; EP1402181B1; ATE329154T1; DE50207116D1; JP2004533385A

Abstract

The invention relates to a device for transporting a bulk product to be transported. Said device comprises at least one transport piston (24) which moves back and forth by means of hydraulic systems (26), a support tube (30) which axially guides the transport piston on its generated surface (42), a filling chamber (20) which is axially connected to the support tube in the direction of transport and which can be supplied with the product to be transported by means of a supply funnel (12), and a transport cylinder (32) which is axially arranged in the displacement path of the transport piston, and is connected to the filling chamber on the input side and to a discharge tube (14) on the output side. The transport piston enables the supply funnel to access the filling chamber, when said transport piston is in its final position - withdrawn into the support tube (30) - while when it advances, it penetrates the filling chamber, entraining the product to be transported, and enters the transport cylinder. According to the invention, the discharge tube comprises a free outlet (38) for the product to be transported, on the end thereof opposite the transport cylinder. During the transport operation, an air-tight plug is formed in the discharge tube, consisting of a compressed product to be transported, which can be formed by means of a progressive product to be transported and which can be withdrawn by means of its outlet.

Description

Device for conveying flowable and pourable material

description

The invention relates to a device for conveying flowable or pourable conveyed material with at least one delivery piston, which can preferably be pushed back and forth by hydraulic means, with a bearing tube axially leading the delivery piston on its outer surface, with an axially adjoining the bearing tube in the conveying direction, via a feed channel or hopper with filling material that can be conveyed, and with a delivery cylinder arranged axially in the displacement path of the delivery piston, connected on the inlet side to the filling chamber and on the outlet side to a discharge tube, the delivery piston releasing the filling chamber to the feed channel or hopper in its end position retracted into the storage tube and at Feed penetrates the filling space with the conveyed material and penetrates into the feed cylinder.

In a known conveyor device of this type (EP-B-0 681 672), which is intended for the transport of metal scrap, the delivery piston designed as a plunger cylinder is guided in a sliding guide of the bearing tube. In addition, inward-pointing grooves for receiving wiper and fine sealing rings are screwed into the bearing tube near its end on the filling chamber side. The gap between the bearing tube and the delivery piston is supplied with lubricating oil via lubrication holes in a central lubrication system. The piston penetrating into the feed cylinder lies against the wall on the inlet side, so that a vacuum is created with each return stroke. In order to ensure that no material is sucked back from the feed pipe into the filling chamber during the return stroke, a cross slide is arranged in the feed pipe behind the feed cylinder, which is closed before each return stroke of the feed cylinder and opened again before each pressure stroke. The high susceptibility to wear in the area of the bearing tube is a disadvantage considered. In addition, the known conveying device is not readily suitable for conveying the material to be conveyed from a pressurized filling space into an atmospheric outside space without the risk of a pressure breakthrough.

The invention has for its object to improve the known device of the type mentioned in such a way that even when a pressure difference between the filling space and the outside space is maintained, discharge of the conveyed material in a stationary operation without a slide is possible.

To achieve this object, the combination of features specified in claim 1 is proposed. Advantageous refinements and developments of the invention result from the dependent claims.

The solution according to the invention is based on the procedural idea that an airtight plug consisting of compressed material to be conveyed is produced in the discharge tube before its outlet opening, with at least part of the plug on each delivery stroke of the delivery piston due to advancing and material which compresses via the outlet opening in the outside space is displaced. To make this possible, it is proposed according to the invention that the discharge tube has a free discharge opening for the material to be conveyed at its end facing away from the feed cylinder, that between the inner surface of the feed cylinder and the lateral surface of the feed piston penetrated into it, a gap for the air passage between the filling space and remains free of the pipe section and that an airtight plug is formed in the discharge pipe during conveying operation, which can be built up by moving material to be conveyed and can be pushed out via its outlet opening. A preferred embodiment of the invention provides that the outlet opening of the discharge tube is formed by a diaphragm with a diaphragm diameter which is smaller than the inside diameter of the discharge tube. The diaphragm is expediently detachable and / or interchangeably arranged on the discharge tube.

According to a further advantageous embodiment of the invention, the plug is mechanically divided in the area of the outlet opening when it exits into the outside space. For this purpose, a separating member can be arranged in the area of the outlet opening for dividing the plug portion which is forced outward during the conveying stroke.

At the beginning of a conveying process, when the discharge pipe is still open to the filling chamber, a base plug must first be generated to ensure the stationary conveying operation. In order to make this possible, it is proposed according to a preferred embodiment of the invention that, in order to produce a base plug, material to be conveyed is first compressed with the delivery piston in a space between the delivery cylinder and the discharge tube, and that the base plug thus formed with the delivery piston is then moved forward with an open space and material which condenses and is plugged out is discharged into the discharge pipe. For this purpose, a further pipe section, which cannot be penetrated by the delivery piston, and a slider which penetrates the pipe section transversely are arranged between the delivery cylinder and the discharge pipe.

In order to improve the performance of the conveying device, two conveying cylinders with a subsequent discharge tube are provided, the two conveying pistons penetrating into the conveying cylinders being operable in push-pull. A pipe section with a cross slide is provided between the feed cylinders and the associated discharge pipe. So that's it possible to generate the necessary material plug independently of each other in each discharge pipe. For reasons of space, the two cross slides are expediently arranged at a lateral and axial distance from one another.

For the production of the base plug and for the monitoring of the delivery operation, it is advantageous if each delivery piston is equipped with a position measuring system with which the stroke of the delivery piston can be measured at any time.

The invention is explained in more detail below on the basis of an exemplary embodiment shown schematically in the drawing. Show it

1a shows a diagrammatic representation of a spoil discharge lock for use in tunnel construction;

1b and 1c show a side view and a top view of the discharge lock according to FIG. 1a with the feed hopper placed on the filling space;

1d a side view of a tunnel boring machine with discharge lock and FIGS. 1a to c;

2a to c show two longitudinal sections offset by 90 ° with respect to one another and a cross section of the delivery piston designed as a plunger cylinder of the discharge device according to FIGS. 1a to c;

3a and b show an end view and a side view of the sealing cassette of the bearing tube on the filling chamber side;

3c shows a section along the section line A - A of FIG. 3a; 4a to e an enlarged detail from FIG. 3c in different sectional planes A to E of FIG. 3a;

Fig. 5a is a plan view of the segmented scraper ring

Sealing cassette according to Fig. 4a to e;

Fig. 5b is a plan view of one of the cutting ring segments

Fig. 5a;

5c shows a section along the section line A - A of FIG. 5b;

6a and b show a side view and an inside view of a segment of the fine seal according to FIGS. 4a to e;

7a to d a guide roller of the bearing tube of the discharge lock according to Fig. 1a to c in a diagrammatic representation and in three side views.

The discharge lock 8 shown in the drawing is intended for use in tunnel boring machines 1. For this purpose, it has an obliquely upwardly directed flange plate 10 and a feed hopper 12, with which it can be connected to a transport pipe 3 equipped with a screw conveyor 2 for the waste 5 accumulating in the excavation chamber 4 of the tunnel boring machine 1. The earthy or rocky overburden 5, which as a rule cannot be pumped, is fed under a pressure P> P _atm ^UDer which is increased due to the earth pressure, a stone crusher 7 and the feed hopper 12 of the discharge lock 8 and via the discharge pipes 14 against atmospheric pressure p _atm for further conveyance, for example via a belt conveyor 6 removed. The two hooks 16 arranged in the vicinity of the flange plate 10 serve to facilitate assembly and maintenance. In the exemplary embodiment shown, the discharge lock 8 has two conveying devices or lock parts 18 which operate in push-pull and which are constructed essentially the same. The two lock parts each contain a filling space 20, which are separated from one another by a partition 22 and can be fed with conveyed material via the common feed hopper 12. In each lock part there is a delivery piston 24 designed as a plunger, which can be pushed back and forth via a hydraulic drive cylinder 26. A support cage 28, a bearing tube 30, one of the filling chambers 20, a delivery cylinder 32, an intermediate tube 34 with a cross slide 36 and one of the discharge tubes 14 are assigned axially one behind the other to each delivery piston 24. In their end position, which is retracted into the bearing tube 30, the delivery pistons 24, which can be driven in push-pull, release the filling chamber 20 to the feed hopper and penetrate into the respective delivery cylinder 32 when the material is conveyed, taking the conveyed material with it. The material to be conveyed is compressed in the feed cylinder 32, in the subsequent intermediate tube 34 and in the discharge tube 14 to form a plug so that there is an airtight seal between the filling space 20 and the outside space located outside the outlet opening 38 of the discharge tube 14.

With each delivery stroke, part of the plug is displaced outward via the outlet opening 38. Knife-like separating members 40 are located in the outlet opening 38, which break up and break up the emerging plug section. With each conveying stroke, the plug is replaced by compressed material to be conveyed.

At the beginning of a funding process, if there is no grafting, a grafting must first be built up. For this purpose, the two cross slides 36 are provided, which are offset from one another in the axial direction for reasons of space. First the cross slide moved to its closed position. The material to be conveyed is then pressed with the respective delivery piston 24 with reduced feed force against the cross slide 36 engaging in the feed path within the intermediate tube 34 and thereby compressed to form a plug. The displacement path of the delivery piston 24 is monitored by a displacement measuring system 62, 64 connected to the hydraulic drive cylinder 26. As soon as a sufficient plug is built up, the cross slides 36 are opened and the plugs are moved into the associated discharge tube 14 during the subsequent conveying strokes of the conveying piston 24 until they reach the outlet opening 38. In order to influence the formation of a plug, depending on the consistency of the conveyed material, and to support an existing plug, it is possible to use diaphragms (not shown) with different opening cross sections in the area of the outlet openings 38.

To avoid the formation of a vacuum when the piston is withdrawn from the cylinder, which could lead to the plug being broken open, delivery pistons 24 and delivery cylinders 32 are dimensioned such that a gap for the air passage between the filling space 20 and the intermediate tube 34 remains free between them. The inner surface of the discharge pipe, the intermediate pipe and possibly also the delivery cylinder are equipped with wear strips, which are screwed detachably from the outside through the respective pipe wall. The wear strips complement one another to form a non-circular cross-section, preferably a polygonal inner surface.

As can be seen from FIGS. 2a to c, the lateral surface 42 of the delivery piston 24 is formed by an elongated hollow cylinder 44, the free end face of which is closed by an end plate 46 and in which the hydraulic drive cylinder 26 is located. The cylinder part 48 of the drive cylinder 26 is articulated on its base part 50 via a joint 52 at the rear end of the support cage 28 and on its rod end via two support rollers 54, which are at an angular distance of 90 ° from one another have, supported and guided on the inner surface of the hollow cylinder 44. The piston rod 56 of the drive cylinder is articulated on the inside of the end plate 46 via a joint 58. The hinge axes of the joints 52 and 58 are perpendicular to one another and aligned with the direction of displacement of the piston rod 56. The piston rod 56 has an axis-central cavity 60, into which a stainless steel tube 62, which protects a waveguide and which is fixed at the bottom end of the cylinder part, engages axially centrally. Together with a permanent magnet 64 that is fixed to the piston rod, the waveguide 62 forms the position measuring system with which the current displacement position of the delivery piston 24 can be measured.

The support piston 24 is supported and guided axially centrally within the bearing tube 30. For this purpose, guide rollers 66 are arranged on the outside of the bearing tube, and their running surface 68 extends through wall openings of the bearing tube in the direction of the outer surface 42 of the delivery piston. The guide rollers 66, which are made of an elastomeric material, preferably of heavy-duty polyamide, are each mounted on a bearing block 70. Each bearing block is articulated at one end to a pivot bearing 72 which is fixed to the bearing tube and is screwed to the bearing tube 30 at its other end by means of a spring-assisted screw 74. The running surface 68 of the guide rollers has a concave transverse curvature which is complementary to the outer surface 42 of the delivery piston 24 (FIG. 7c). As can be seen from FIGS. 1 a to c, the guide rollers are arranged in three axial positions spaced apart from one another and in three circumferential positions spaced apart from one another in the circumferential direction, each circumferential position being equipped with two guide rollers arranged next to one another. The feed piston 24 is dimensioned such that it moves out of the region of the guide rollers 66 located in the rear axial position when it is moved into the feed cylinder 32. At its end on the filling chamber side, the bearing tube 30 has a sealing cassette 76, which is clamped in a floating manner between two O-rings 78, 80 in a recess in the bearing tube end with the aid of a clamping ring 82 and is easily replaceable. The sealing cassette 76 has a metallic, ring-shaped base body 84, which is provided on the inside with circumferential grooves 86 for receiving a radially adjustable wiper 88 and a radially adjustable fine seal 90 made of elastomeric material. The circumferential grooves 86 for the wiper 88 and for the fine seal 90 are delimited by an insert ring 94 arranged in an annular recess 92 of the base body 84. As can be seen from FIGS. 5a to c, 6a and b, the wiper 88 and the fine seal 90 are composed of several segments 88 ', 90' divided in the circumferential direction, each against a radially outer elastomeric ring 96, 98 apply, and can be acted upon indirectly with a pressure medium, for example with grease. The segments 88 ', 90' of the scraper 88 and the fine seal 90 have mutually complementary grooves for receiving a closed elastomeric retaining ring 104, 106 and are supported in the region of the retaining ring against the associated radially outer sealing ring 96, 98. To ensure that the segments 88 'of the scraper 88 do not twist in the circumferential direction, they are fixed in the circumferential direction with the aid of pins 130 inserted into the insert ring 94 via the recesses 132 in the segments 88' (see FIGS. 5a to c and Fig. 4a and d). It can be seen in FIG. 6 b that the fine sealing segments 90 ′ have steps 120 that overlap one another in the circumferential direction. In addition, the fine sealing segments 90 'are composed of two elastomeric segment parts 90 ", 90"' with different hardness. The circumferential grooves 86 for the wiping segments 88 'and the fine sealing segments 90' can be acted upon independently of one another with pressure medium via channels 108, 110 in the base body. For this purpose, the insert ring is also provided with ring channels for circumferential grooves 112, 114 which delimit the pressure medium supply and open to the edge of an annular surface 116 of the base body Mistake. The circumferential grooves 112, 114 are sealed off from one another and to the outside by sealing rings 118 arranged in adjacent circumferential grooves.

Another channel 122 is used to supply a lubricant or flushing agent. On its inner surface, the base body has further circumferential grooves for receiving a grooved ring 124 and an elastomeric guide band 126.

The sealing cassettes 76 can be prefabricated and exchanged as a whole. In order to hold the segmented wipers 88 and fine seals 90 as well as the grooved rings 124 and guide bands 126 in position in the prefabricated state, a mounting tube 128 is provided which is pushed out of the sealing cassette during the assembly process when the sealing cassette 76 is pushed onto the delivery piston 24.

In summary, the following can be stated: The invention relates to a device for conveying flowable and pourable material to be conveyed. It has at least one delivery piston 24, which can preferably be pushed back and forth by hydraulic means 26, a bearing tube 30 axially guiding the delivery piston 24 on its outer surface 42, a filling chamber 20 axially adjoining the bearing tube in the conveying direction, which can be filled with material to be conveyed via a feed funnel 12, and an axially arranged in the displacement path of the delivery piston 24, connected on the input side to the filling chamber 20 and on the output side to a discharge pipe 14. The feed piston 24, in its end position retracted into the bearing tube 30, frees the filling space 20 to the feed hopper 12, while during the feed it penetrates the filling space 20 with the conveyed material being carried and penetrates into the feed cylinder 32. In order to be able to maintain a pressure difference between the filling space 20 and the outside space with simple means, it is proposed according to the invention that the discharge tube 14 at its end facing away from the feed cylinder 32 has a free outlet opening 38 for the material to be conveyed that between the inner surface of the feed cylinder 32 and the outer surface 42 of the feed piston 24 which has penetrated into it, a gap space for the air passage between the filling space 20 and the discharge pipe 14 remains free and that in Discharge tube 14 is formed in the conveying operation of an airtight plug which can be built up by advancing conveyed material and can be extracted via its outlet opening 38 and consists of compressed conveyed material.

Claims

claims

1. Device for conveying flowable and pourable material to be conveyed with at least one delivery piston (24) which can preferably be pushed back and forth by hydraulic means, with a bearing tube (30) which axially guides the delivery piston (24) on its outer surface (42), with one the storage tube (30) axially adjoining in the conveying direction, via a feed channel or hopper (12) which can be filled with material to be conveyed, and with an axially arranged in the displacement path of the conveying piston (24) on the inlet side on the filling chamber (20) and on the outlet side a discharge pipe (14) connected to the delivery cylinder (32), the delivery piston (24) in its end position retracted into the bearing tube (30) releasing the filling space (20) to the feed channel or funnel (12) and when filling the filling space (20) Carriage of conveyed material penetrates and penetrates into the conveying cylinder (32), characterized in that the discharge tube (14) on the conveying cylinder (32) is turned away at the other end has a free outlet opening (38) for the material to be conveyed, that between the inner surface of the conveying cylinder (32) and the outer surface (42) of the penetrating delivery piston (24) there is a gap for air to pass between the filling chamber (20) and the discharge pipe (14 ) remains free, and that in the discharge pipe (14) during the conveying operation, an airtight plug that can be built up by advancing material to be conveyed and that can be extracted via its outlet opening (38) is formed.

Apparatus according to claim 1, characterized in that the outlet opening (38) of the discharge tube (14) is formed by an orifice with an orifice diameter which is smaller than the inside diameter of the discharge tube.

3. Apparatus according to claim 2, characterized in that the aperture is detachably and / or interchangeably arranged on the discharge tube (14).

4. Device according to one of claims 1 to 3, characterized in that exchangeable wear strips are arranged on the inner surface of the discharge tube (14) and / or the feed cylinder (32).

5. The device according to claim 4, characterized in that the wear strips are fastened by screws passing from the outside through the pipe wall to the feed cylinder (32) and / or discharge pipe (14).

6. The device according to claim 4 or 5, characterized in that the wear strips complement each other to a non-circular in cross section, preferably polygonal inner surface.

7. Device according to one of claims 1 to 6, characterized in that between the delivery cylinder (32) and discharge pipe (14) another pipe section not penetrable by the delivery piston (32)

(34) and a slider which penetrates the tube section (34) transversely

(36) is arranged.

8. Device according to one of claims 1 to 7, characterized in that two delivery cylinders (32) with a subsequent discharge tube (14) are provided.

9. The device according to claim 8, characterized in that between see the delivery cylinders (32) and the associated discharge tube (14) each have a tube section (34) with cross slide (36) is arranged.

10. The device according to claim 9, characterized in that the two cross slides (36) are arranged at a lateral and axial distance from one another.

11. Device according to one of claims 7 to 10, characterized in that on the inner surface of the tube section (34) are arranged distributed over the circumference, preferably complementary to a polygonal inner surface, interchangeable wear strips are arranged.

12. Device according to one of claims 1 to 11, characterized in that in the region of the outlet opening (38) a separating member (40) for dividing the plug portion pushed outwards during the conveying stroke is arranged.

13. Method for discharging flowable and pourable material to be conveyed from a pressure chamber (20), in which a delivery plunger (32) penetrates through the pressure chamber (20) while carrying material to be conveyed into a delivery cylinder (32) and the material to be conveyed through a discharge pipe

(14) displaced through an outlet opening (38) into an external space, characterized in that an airtight plug consisting of compressed material to be conveyed is produced in the discharge tube (14) in front of the outlet opening (38), at least part of the plug being produced with each delivery stroke of the delivery plunger (32) is displaced into the outside space via the outlet opening (38) due to the material to be conveyed advancing and forming a plug.

14. The method according to claim 13, characterized in that the plug in the region of the outlet opening (38) is mechanically divided when exiting into the outer space.

5. The method according to claim 13 or 14, characterized in that in order to produce a base plug, material to be conveyed is first compressed into an interposed space (34) between the delivery cylinder (32) and discharge pipe (14) with the delivery piston (32) and that subsequently the base plug thus formed is pushed out into the discharge tube (14) with the delivery cylinder (32) with the intermediate space (34) open and the material to be conveyed advancing and compacting with the formation of a stopper.