WO2015024558A1

WO2015024558A1 - Suction excavator for pneumatically taking in material to be suctioned

Info

Publication number: WO2015024558A1
Application number: PCT/DE2014/100293
Authority: WO
Inventors: Karl-Heinz Renger; Marina Renger; Jens Graber
Original assignee: Reschwitzer Saugbagger Produktions Gmbh
Priority date: 2013-08-22
Filing date: 2014-08-20
Publication date: 2015-02-26
Also published as: DE102013109074A1

Abstract

The invention relates to a suction excavator (1), wherein an air flow (12), which has been heated while passing through a fan (7), is used to heat, keep warm, and thaw already iced components of the suction excavator (1). The air flow (12) can be diverted from an exhaust air channel (8) as a guided air flow (12.1, not shown in Fig. 1) by means of an air flow switch (10) and can be distributed in the suction excavator (1) by means of a return channel (9) having outlets (11). The suction excavator (1) according to the invention can be operated in a short-circuited flow state, in which the air flow (12) is recirculated within the suction excavator (1).

Description

Suction dredger for pneumatic intake of suction material

The invention relates to a suction dredger for pneumatic intake of suction material in the form of solid or liquid media from an environment of the suction dredger by means of a fast-flowing air flow, as this generic from DE 33 18 765 C2 is known.

There are a whole series of suction dredgers known from the prior art, all as essential components a suction hose with a suction mouth, as a separator serving collecting container for receiving the separated suction material, optionally a baffle plate, which deflects the subsidized suction material, for example, down Have filter system for cleaning the air flow and at least one fan with a Zuluft- and an exhaust duct for generating the air flow. Such suction dredgers are described in the only example cited documents DE 38 10 932 A1 and DE 200 04 860 111.

Based on the basic components mentioned, suction dredgers have been further developed and improved in many details in recent years. This suction dredger for low-damage excavation of z. For example, earths in the field of utility lines in construction technology have been well known in recent years and accepted as safe building technology.

In all suction dredgers on the market, centrifugal fans generate large, very fast-flowing air streams, which entrain a material to be picked up (henceforth suction material), which is located in the area of the suction orifice.

However, these fast air currents also cause adverse effects. At temperatures around the freezing point, these air streams lead to a rapid cooling of the fluidically arranged before the fan components of the suction dredger. At temperatures around 0 ° C and even slightly above, these air-bearing components of the suction dredge start to freeze. In this case, moist suction material on the walls, such as the suction hose or the separator, freeze. In the suction hose is thereby an adverse reduction of the suction cross-section caused. Likewise, existing ultrafine filter cartridges can freeze the filter system. This is favored by the fast-flowing air currents still. The extremely disadvantageous freezing of the components of the suction dredger potentially occurs in all known suction dredger models when operated at correspondingly low ambient temperatures. From the prior art, no solution is known by means of which a freezing of components of the suction dredger, without the addition of external energy, can be prevented or by the thawing already iced components is made possible on site. Foreign energy can be, for example, a heating of the air to be sucked or the air flow by a heat input by means of gas burners.

In the aforementioned DE 33 18 765 C2 a suction dredger is described, which has the above-mentioned technical components. From a stream of air that is generated by a fan and sucked by the suction material via a suction hose and can be divorced to a large extent in a collecting container, a proportion is deflected and directed as return air (henceforth: supplied air flow) via a return channel back to the suction port and provided there as blowing air. In this case, the supplied air flow is performed at the suction mouth in a special way to produce an inwardly rotating air curtain. Downstream of the filter unit and the fan is a cyclone separator in which particles still remaining in the air flow are separated from the airflow.

Most of the airflow is blown out to the environment. A portion of the air flow can be used as described above as supplied air flow, while a further portion is supplied from the cyclone separator via a separate air duct again to the sump. By this further portion of the air flow separated particles are transferred to the collecting container and deposited there in the cyclone. The suction dredge according to the aforementioned DE 33 18 765 C2 therefore has, in addition to an exhaust duct and a return duct for generating and providing a blown air and an additional Lüftführungskanal for transporting separated particles from the cyclone separator in the collection on.

The invention has the object to provide a way to avoid and to eliminate unwanted icing when using a suction dredger at low temperatures.

The object is solved by the subject matters of the independent claims. Advantageous embodiments are specified in the dependent claims.

The object is achieved by a suction dredger for pneumatic intake of suction material in the form of solid or liquid media from an environment of the suction dredger by means of a fast-flowing air flow, that the heat energy of the air flow in the exhaust duct individual or all components is supplied at least temporarily.

The suction dredger has at least the following components: a suction hose with a suction mouth, a separator for separating the suction material from the air flow, a filter system for cleaning the air flow and at least one fan with a Zuluft- and an exhaust duct for generating the air flow.

An inventive suction dredger is characterized in that an air flow diverter and a return channel for returning portions of the air flow or the entire air flow to a single component or to several components of the suction dredger are present. The return channel has an input and a plurality of outputs. The outputs are flow-conducting and / or flow-blocking elements (hereinafter also referred to collectively as flow-regulating elements) for ventilating one or more Assigned components so that one or more components can be ventilated controlled. The input of the return channel is connected via the air flow switch with the exhaust duct.

In a suction dredge according to the invention, the air flow heated by the compression can be partially or completely returned via the return duct to one or more components on the suction side (components which are upstream of the at least one fan in terms of flow) at the outlet side of the fans. The amount of recirculated air is adjustable via the controlled air flow switch. Depending on the control state of the air flow switch, it is possible to effect a ventilation and thus thermal short circuit. The components to be heated are assigned flow-regulating elements, so that one or more components can be heated under control. The input of the return channel is connected via the air flow switch with the exhaust duct.

The return duct serves to return either portions of the airflow or the entire airflow to a single component or multiple components of the suction dredger. For this purpose, the existing current-regulating elements, preferably individually, can be controlled. By a targeted control of the current-regulating elements, it is possible to selectively supply a portion of the air flow of the exhaust duct selected components of the suction dredger. Flow-regulating elements can, for. B. slides, flaps or valves.

A flow-regulating element is assigned to an output, if, as a result of an activation of this output-regulating current-regulating element, the proportion of the supplied air flow, which is supplied by the respective output of a component of the suction dredge, is controllably adjustable. An outlet is assigned in advantageous embodiments, a single flow-regulating element. It is advantageous if the flow-regulating element is designed and articulated so that either the return channel or the outlet can be completely closed by various positions of the current-regulating element and also by the intermediate positions of the current-regulating element portions of the supplied Air flow through the outlet and further portions of the supplied air flow through the return channel can be passed.

As a return channel, the area is defined within which the air stream heated as a result of the compression of the at least one fan can be guided as a supplied air flow and fed to individual components of the suction dredger.

The return channel can have different cross sections and dimensions, which can also be changed along the path of the return channel. In further embodiments of the suction dredger according to the invention, the return channel can also be designed to be divided and consist entirely or partially of a plurality of individual channels. A set of inputs from several individual channels is considered as an input in the sense of this description.

By the air flow diverter, which may be formed, for example, as a hinged flap, the guided in the exhaust duct air flow is at least partially deflected in the return duct.

The essence of the invention is to use thermal energy of the air flow of the exhaust duct, in particular heat energy generated by the compression inside the fans, to avoid icing. The airflow can be used for heating, keeping warm and / or drying components as well as thawing already frozen components.

The invention is therefore based on the consideration to use a heat energy of an air flow of a suction conveyor to prevent freezing of components of the suction conveyor and / or thawing frozen components of the suction conveyor, wherein the heat energy is transferred to the air flow due to compression of the air flow and at least parts the transferred heat energy selected components of the suction conveyor are supplied by controlled portions of the heated air stream are fed to the selected components. In the case of the complete return of the air flow and thus the thermal short circuit, the temperature of the air flow increases with each pass through the fan. Since the internal air volume of suction dredgers is subordinate to the amount of air flow generated by the fan, a complete thermal short circuit results in a sudden increase in the temperature of the air flow. In order to avoid damage to the suction dredge due to excessive temperatures of the air flow, the air flow diverter is advantageously controllable by evaluating measured values of temperature sensors.

In particular, when using centrifugal fans, the air flow is sucked in, accelerated and compressed. The compression is in high-performance fans in the range of about 0.2 bar. For multi-stage, serially arranged fans, this compression value increases per level accordingly. Due to the compression of the air stream, it is heated up to 20 K per fan step.

The fan is preferably a radial fan. It may also be an axial fan or a fan of a different design in further embodiments of the suction dredge according to the invention. There may be several similar or different fans.

The channels such as supply air duct, exhaust duct and return duct are preferably made of metal and can have different cross sections, z. B. round or square, have.

The outputs of the return channel may be formed, for example, as holes or slots in an outer wall of the return channel. These outputs are each assigned a flow-regulating element. The control of the flow-regulating elements can be realized mechanically, electrically, hydraulically or pneumatically and monitored and triggered by a controller. A control can also be manually possible in addition to computer-based or loop-based controls.

In further embodiments of the suction dredge according to the invention, individual or all flow-regulating elements can also be actuated. So can as flow-conducting elements acting baffles controllable with respect to their angle of attack to the air flow, for example, pivotally be.

It is advantageous if the air flow switch can be controlled, so that metered between 0 and 100% of the air flow in the exhaust duct can be passed as a supplied air flow in the return channel. If the entire air flow is passed as supplied air flow in the return channel to the inner components of the suction dredger, the suction dredger is operated in an internal flow circuit (air short circuit state). The air flow is circulated inside the suction dredge and further heated. This operating state of the suction dredger is particularly suitable for thawing already frozen components and to warm components of the suction dredger. For this purpose, the suction dredger can remain at his work and must not be spent for thawing to another place. As a result, efficient use of a suction dredge according to the invention is also supported at low ambient temperatures. After sufficient heating of the components by driving the air flow switch and optionally the flow regulating elements again a delivery state as the operating state of the suction dredger reached in which a portion of the air flow, or the entire air flow is blown through the exhaust duct into the environment or wholly or partially to the suction port to be led.

If the entire air flow is directed outwards to the suction orifice, this is only a partial short circuit, since the suction hose always also draws in outside air.

In one embodiment of a suction dredge according to the invention, therefore, at least one outlet can be arranged at a distance in front of the suction mouth. The distance and the orientation of the outlet are chosen such that a portion of the air stream that is discharged from the outlet is at least partially sucked back in via the suction mouth and returned to the suction dredger. By such a design, a proportion of the warm air flow in front of the suction orifice can be conducted and is sucked back into the suction hose to a large extent during operation of the suction dredge. Due to the warm air flow, the suction hose is heated, creating a Icing of the suction hose is reduced or completely prevented. In order to be able to respond to different ambient temperatures and working conditions of the suction dredger, the distance of the output of the suction orifice can be adjustable.

The air flow switch and the return duct are advantageously usable for heating one or more components, wherein the heat of the supplied air flow is transferred to one or more components. The heating of the components takes place by heat conduction, heat transfer and / or convection. A further advantage of the suction dredger according to the invention is that wet-cleaned fine filters can be dried again particularly easily in short-circuit operation. In the case of a pure short-circuit operation, sudden increases in temperature occur, which can even reach critical temperatures. The short-circuit operation is therefore particularly suitable for quickly reaching a desired target or target temperature. After reaching the target or target temperature then the desired or target temperature must be kept constant by means of an intelligent, controlled by measured values of temperature sensors adjustment system of the air flow switch.

The invention will be explained in more detail with reference to figures and embodiments. Show it:

Fig. 1 shows a first operating state of an embodiment of an inventive

Suction dredger in the pure conveying state, without recirculation of an air flow,

Fig. 2 shows a second operating state of the embodiment of the invention

Suction dredger with complete return of the air flow and

Short-circuit operation with maximum heating of components of the suction dredger without material conveyance and

Fig. 3 shows a third operating state of the embodiment of the invention

Suction dredger with partial return of the air flow and thus controlled heating of the components of the suction dredger. 1-3, a suction hose 2 with suction mouth 2.1, a separator 3, a filter unit 4, a fan 7, an exhaust duct 8, an air flow switch 10 and a return duct 9 with an input and shown with outputs 1 1.

In the exhaust duct 8, the return duct 9 opens with its input to which the air flow switch 10 is arranged to be movable and controllable. In the return channel 9 outputs 1 1 are present, through which a portion of a supplied air stream 12.1 emerges from the return channel 9. The outputs 1 1 are directed to the filter unit 4 and 3 in the separator. In the return channel 9 also flow-regulating elements 13 in the form of individually controllable flaps are present, which are each associated with one of the outputs 1 1. The control of the air flow switch 10 and the flow-regulating elements 13 is hydraulically via a controller 14. Depending on the control state of the flow-regulating elements 13, a proportion of the supplied air flow 12.1 is directed through the outputs 1 1. Through each of the flow-regulating elements 13 in the return channel 9, the supplied air stream 12.1 controlled throttle or even completely shut off. Depending on which of the flow-regulating elements 13 throttling or blocking the supplied air flow 12.1 and depending on the degree of the respective throttling, portions of the supplied air flow 12.1 can pass through those outlets 11 that are fluidically arranged in front of the corresponding flow-regulating element 13.

In Fig. 1, a first operating state of the suction dredger 1 is shown, in which a delivery of a suction material 5 is possible without a return of at least portions of an air stream 12 takes place. When running, designed as a radial fan fan 7, an air flow 12 is generated, which passes from an environment of the suction dredge 1 through the suction mouth 2.1 in the suction hose 2 and from there into the separator 3. It is entrained by the air flow 12 Suction 5 from the periphery of the suction port 2.1. In the separator 3, the air stream 12 slows down and loses transportability. The suction material 5 falls out of the air flow 12 and remains in the separator 3, while the air flow 12 passes through the filter system 4 and over a supply air duct 6 passes to the fan 7. In the fan 7, the air flow 12 is compressed, thereby heated and pressed into the exhaust duct 8.

In the first operating state of the suction dredger 1 shown in FIG. 1, the return duct 9 is completely closed by the airflow diverter 10. The sucked and compressed by the fan 7 and heated air flow 12 is discharged via an exhaust duct opening of the exhaust duct 8 directly to the environment. The positions of the flow-regulating elements 13 in the return channel 9 are insignificant in the first operating state shown.

2, a second operating state of the suction dredger 1 is shown. The air flow switch 10 is controlled and placed so that the exhaust duct 8 is completely closed and thus the entire air stream 12 is fed as supplied air stream 12.1 in the return channel 9. By the flow-regulating element 13, which is associated with the directed into the filter system 4 output 1 1, this output 1 1 is completely closed and at the same time allows a non-throttled passage of the supplied air stream 12.1 through the return channel 9.

In contrast, the flow-regulating element 13, which is assigned to the output 1 1 directed into the separator 3, is so controlled and set up that the return channel 9 is completely closed by this flow-regulating element 13. At the same time directed into the separator 3 output 1 1 is fully open, so that the entire supplied air flow 12.1 is passed into the separator 3.

By such a guide of the supplied air flow 12.1 at least the uppermost in the separator 3 suction material 5 and the separator 3 and the leading from the separator 3 to the filter system 4 air channels are heated.

In the second operating state, an air-technical short circuit of the suction dredger 1 is effected. The directed into the separator 3 supplied air stream 12.1 is again sucked by the fan 7, compressed, further heated and in turn passes through the return channel 9 in the separator 3. Since the air flow 12 at each pass through the Fan 7 is heated further, this operating state causes a very rapid heating of the air flow 12 through which the components.

In modifications of the second operating state, the flow-regulating element 13 may be fully opened at the directed into the filter unit 4 output 1 1, whereby the return channel 9 would be closed by the flow-regulating element 13 to the output 1 1 and the entire supplied air stream 12.1 to the filter system would be directed.

In Fig. 3, a third operating state of the suction dredger 1 is shown, in which the air flow switch 10 is in a half-open position. About half of the air flow 12 is blown through an exhaust duct opening of the exhaust duct 8 into the environment. The other half of the air flow 12 is directed by the air flow switch 10 as a supplied air flow 12.1 in the return channel 9.

The flow-regulating elements 13, which are associated with the outputs 1 1, which are directed into the separator 3 and the filter unit 4, are half open during the third operating state. A proportion of the supplied air flow 12.1 is therefore in the separator 3 and a further portion of the supplied air flow 12.1 is directed to the filter unit 4. These portions are again compressed and heated in a renewed passage of the fan 7. At the same time 12 components of the suction dredger 1 are kept warm by these portions of the air flow.

The remaining portion of the supplied air flow 12.1, however, is guided by the return channel 9 in the direction of the suction mouth 2.1. At a distance in front of the suction orifice 2.1, an outlet at the suction orifice 1 1.1 is present, through which the remaining portion of the supplied airflow 12.1 exits from the return duct 9 and at least partially through the suction orifice 2.1 is again sucked into the suction hose 2. By this re-absorbed portion of the suction hose 2 is heated.

The distance of the output at the suction port 1 1 .1 of the suction port 2.1 is manually adjustable. In a further embodiment, the distance may also be pneumatically, electromotively, hydraulically or mechanically adjustable. In other embodiments of the suction dredger 1 according to the invention other numbers and courses of return channels 9 and other numbers and orientations of outputs 1 1 may be present.

The controller 14 may in further embodiments of the suction dredger 1 according to the invention with measuring means (not shown), such as icing sensors, humidity sensors and / or temperature sensors, in connection.

LIST OF REFERENCE NUMBERS

1 suction dredger

2 suction hose

2.1 suction mouth

3 separators

4 filter system

5 suctions

6 supply air duct

7 fans

8 exhaust duct

9 return channel

10 air flow switch

1 1 output

1 1 .1 outlet at the suction mouth 2.1

12 airflow

12.1 supplied air flow

13 Flow regulating element

14 control

Claims

claims

1. Suction dredger (1) for the pneumatic intake of suction material (5) in the form of solid or liquid media from an environment of the suction dredge (1) by means of a fast-flowing air stream (12), wherein the suction dredger (1) contains at least the following components:

a suction hose (2) with a suction mouth (2.1),

- a separator (3) for separating the suction material (5) from the air flow (12),

- A filter unit (4) for cleaning the air flow (12) and

- At least one fan (7) with a supply air duct (6) and an exhaust duct (8) for generating the air flow (12),

characterized in that

a return channel (9) for returning portions of the air stream (12) or the entire air stream (12) to a single component or to several components of the suction dredge (1) having an input and a plurality of outputs (1 1) is present,

- The input of the return channel (9) via an air flow diverter (10) with the exhaust duct (8) is connected and

- The outputs (1 1) are assigned controllable flow-regulating elements (13), so that the heat energy of the air flow (12) in the exhaust duct (8) or at least temporarily fed to each component of the suction dredge (1).

2. suction dredger (1) according to claim 1, characterized in that the air flow diverter (10) is adjustable, so that the air flow (12) of the exhaust duct (8) partially or completely as a supplied air flow (12.1) in the return duct (9) can be conducted is.

3. Suction dredger (1) according to claim 1 or 2, characterized in that at least one outlet at the suction mouth (1 1 .1) is arranged at a distance in front of the suction mouth (2.1).

4. suction dredger (1) according to claim 3, characterized in that the distance is adjustable.

5. Use of the air flow diverter (10) and the return duct (9) with a suction dredge (1) according to one of claims 1 to 4 for heating one or more components of the suction dredger (1), wherein heat of the supplied air flow (12.1) on one or several components of the suction dredger (1) is transmitted.

6. Use according to claim 5, characterized in that the entire air flow (12) by means of the air flow switch (10) as supplied air flow (12.1) in the return duct (9) is passed and the total supplied air flow (12.1) through at least one of the outputs (1 1) components of the suction dredge (1) is supplied.

7. Use according to claim 5, characterized in that at least a portion of the air flow (12) by means of the air flow switch (10) is supplied as supplied air flow (12.1) in the return channel (9) and at least a portion of the supplied air flow (12.1) to a suction mouth (2.1) of a suction hose (2) of the suction dredger (1) is passed, so that a portion of the supplied air flow (12.1) is again sucked in at the suction mouth (2).

8. Use according to claim 7, characterized in that a portion of the supplied air flow (12.1) through at least one of the outputs (1 1) components of the suction dredge (1) and a further portion of the supplied air flow (12.1) of the suction port (2) supplied become.

9. Using a heat energy of an air flow (12) of a suction conveyor to prevent freezing of components of the suction conveyor and / or thawing frozen components of the suction conveyor, wherein the heat energy is transferred to the air stream (12) due to compression of the air flow (12) and selected at least proportions of the heat energy transferred Components of the suction conveyor are supplied by controlled portions of the heated air stream (12) are fed to the selected components.