Patent Application
20240093439
The present application claims priority to German Patent Application Serial No. DE 10 2022 123 625.0, filed Sep. 15, 2022, which is incorporated herein by reference.
The invention relates to a curing machine for curing freshly-laid concrete slabs—in particular, concrete roadways extending longitudinally in the working direction.
For the production of concrete roadways, slipform pavers are used, which install the concrete in the correct shape and position. The slipform paver has a smoothing device to smooth the not-yet-cured surface of the concrete slab. After the concrete slab has been smoothed, known curing machines are used, which generally have a texturing device for applying texturing to the fresh concrete slab in the transverse direction and/or longitudinal direction, in order to improve the slab's skid resistance and to increase ride comfort or to reduce the development of tire/road noise. In addition, the curing machines generally have a sprayer for spraying a curing agent—in particular, a dispersion—onto the fresh concrete slab in order to prevent the concrete from drying out prematurely.
DE 10 2014 212 853 A1 (U.S. Pat. No. 9,399,842) describes a curing machine which has not only a texturing device, but also a sprayer. The dispersion can be sprayed with the sprayer onto the surface of the concrete slab after the concrete slab has been processed with the texturing device. To apply the dispersion, the sprayer has a first group of spray nozzles which are arranged at a distance from one another on the machine frame over the entire working width. The dispersion can also be applied with a second group of spray nozzles which are provided on a carriage that can be moved over the entire working width.
The sprayers of known curing machines have a liquid system which comprises liquid lines for conducting liquid, shut-off elements for shutting off individual liquid lines, pumps for conveying a liquid in the liquid lines, a curing agent tank for holding a curing agent, a cleaning agent tank for holding a cleaning agent, and groups of spray nozzles for spraying curing agent onto the concrete slab.
The liquid system of known curing machines is designed such that different operating modes can be executed. In a filling mode, the curing agent tank can be filled with a curing agent. In a spraying mode, the curing agent is sprayed. In addition, a mixing mode is provided in which the curing agent is set in motion in the curing agent tank in order to mix the curing agent. In a cleaning or flushing mode, cleaning or flushing liquid can be conducted to the spray nozzles in order to clean the spray nozzles.
To execute the individual operating modes, it is necessary to open or close individual shut-off elements of the liquid system by hand. This procedure proves complicated and time-consuming. In addition, there is the risk of operating errors. For example, when the spray nozzles are being cleaned, if the wrong shut-off elements are opened or closed, there is the risk of cleaning liquid getting into the curing agent tank. The risk of operating errors also exists if the design of the liquid system requires the use of several pumps for conveying the liquids. If the wrong pumps are switched on or off, malfunctions will result. Furthermore, the use of several pumps leads to higher production costs.
An object of the invention is to simplify the operation of the sprayer of a curing machine and to reduce the risk of operating errors.
The embodiments of the invention described below can comprise one or more of the features or feature combinations mentioned below. A feature denoted by an indefinite article can also be present multiple times if the indefinite article is not to be understood with an explicit indication of only one-time use. A denotation of features by a numeral, e.g., “first and second”, does not preclude that these features can be present more times than the number indicated by the numeral.
The sprayer of the curing machine according to one embodiment is characterized by a controller working together with an operating unit for automatically actuating the at least one pump and the shut-off elements of the liquid system. The controller is configured such that, by manual actuation of the operating unit, a human operator may select a selected operating mode from a selectable group of operating modes. The selectable group of operating modes includes at least two of the following operating modes: a filling mode, spraying mode, mixing mode, and cleaning mode. After selection of the selected operating mode, the at least one pump and the shut-off elements are actuated in such a way that the selected operating mode is executed. In another embodiment the selectable group includes at least three of the operating modes. In a further embodiment the selectable group includes all four of the operating modes.
If a filling mode is provided, the liquid system will be designed such that, in filling mode (A), the curing agent tank (29) is filled with a curing agent. For a spraying mode (B), the liquid system is designed such that curing agent is sprayed with the at least one group (24A, 24B, 27A, 27B) of spray nozzles (25). For a mixing mode (C), the liquid system is designed such that curing agent is set in motion in the at least one curing agent tank (29), and, for a cleaning mode (D), the liquid system is designed such that a cleaning liquid is conducted to the at least one group (24A, 24B, 27A, 27B) of spray nozzles (25).
The controller controls the shut-off elements assigned to the operating mode so that liquid flows along the liquid paths or liquid lines assigned to the operating mode. Consequently, the shut-off elements assigned to the operating mode are automatically, and preferably electrically, actuatable shut-off elements which can be actuated by the controller. The controller can also be configured such that at least three operating modes or all operating modes can be selected and executed by manual actuation of the operating unit. If not all operating modes can be selected, the shut-off element assigned to the non-selectable operating mode can also be an only manually-actuatable shut-off element, or the shut-off elements assigned to the non-selectable operating modes can be manually-actuatable shut-off elements. The possibility of selecting an operating mode by means of an operating unit and the automatic execution of the selected operating mode facilitates operation of the curing machine and reduces the risk of operating errors. For the selection of an operating mode, the operating unit can have, for example, mechanical buttons and/or switches and/or a touchscreen. By selecting an operating mode from the available operating modes, it can be ruled out, for example, that, due to an incorrect manual operation of the shut-off elements, cleaning liquid gets into the curing agent tank, and therefore not curing agent, but cleaning liquid is sprayed onto the fresh concrete slab.
Possible operating errors can also be ruled out by the controller being configured such that several operating modes cannot be selected simultaneously. For example, it can be ruled out that spraying mode and mixing mode are performed simultaneously.
The liquid system can be designed such that its liquid lines form a supply line path for conducting liquid from an external curing agent source into the curing agent tank, wherein the controller is configured such that, in filling mode, the at least one pump is activated so that liquid is pumped from the external curing agent source into the curing agent tank. In filling mode, the controller is also configured such that the shut-off elements assigned to the selected filling mode in the liquid system are actuated so that the liquid flows along the supply line path. Consequently, curing agent can be provided on the construction site in an external tank, and the curing agent can be transferred from that tank into the curing agent tank.
The liquid lines of the liquid system can further form a curing agent supply path for conducting liquid from the curing agent tank to the at least one group of spray nozzles, wherein the controller is configured such that, in spraying mode, the at least one pump is activated so that liquid is pumped from the curing agent tank to the at least one group of spray nozzles. In spraying mode, the controller is also configured such that, in the liquid system, the shut-off elements assigned to the selected spraying mode are actuated so that the liquid flows along the curing agent supply path.
Furthermore, the liquid system can comprise a curing agent circulation path for conducting liquid from the curing agent tank back into the curing agent tank, wherein the controller is configured such that, in mixing mode, the at least one pump is activated so that liquid is pumped from the curing agent tank back into the curing agent tank. In mixing mode, the controller is also configured such that, in the liquid system, the shut-off elements assigned to the selected mixing mode are actuated so that the liquid flows along the curing agent circulation path.
Furthermore, the liquid system can comprise a cleaning agent path for conducting cleaning agents from the cleaning agent tank to the at least one group of spray nozzles, wherein the controller is configured such that the at least one pump is activated in cleaning mode so that liquid is pumped from the cleaning agent tank to the at least one group of spray nozzles. In cleaning mode, the controller is also configured such that, in the liquid system, the shut-off elements assigned to the selected cleaning mode are actuated so that the liquid flows along the cleaning agent path. However, cleaning does not need to include the flushing of the spray nozzles. During cleaning, the spray nozzles can also be closed, so that cleaning agent cannot get onto the fresh concrete slab.
Another aspect of the invention is that the liquid system is designed such that, in filling mode, spraying mode, mixing mode, and cleaning mode, only a single pump is provided for conveying liquid. Since pumps are relatively complex components compared to shut-off elements or lines, production costs can be reduced when there is only one pump.
In one embodiment with only a single pump, the liquid system is designed such that the single pump is arranged in a common line section of the supply line path, curing agent supply line path, curing agent circulation path, and cleaning agent path. The respective operating mode can be executed by the controller actuating individual shut-off elements, so that the single pump conveys the respective liquid to, for example, the nozzles of the at least one nozzle group.
A further aspect of the invention lies in the mixing unit for mixing the curing agent in the curing agent tank. The invention does not make use of the mechanical stirrers provided in the known curing machines. The mixing unit according to the invention is based upon a circulation of the curing agent located in the curing agent tank, which is effected by curing agent being fed to the tank and discharged from the tank. The mixing unit, which comprises a first lance-shaped feed line and a second lance-shaped feed line, which are skewed in relation to each other, is arranged in the curing agent circulation path in such a way that curing agent is fed to the curing agent tank via the lance-shaped feed lines, and curing agent is discharged from the curing agent tank via an outlet. The mixing unit with the skewed feed lines can be inserted from above into an opening of the curing agent tank and removed again.
One embodiment provides that the mixing unit have a mounting part which can be fastened to the curing agent tank and is designed such that the lance-shaped feed lines, in an operating position in which the lance-shaped feed lines are arranged skewed in relation to each other, can be fastened to the mounting part and, in a transport position, can be fastened to the mounting part, in which the feed lines are aligned in parallel. When the mixing unit is not needed, the feed lines can thus be fastened to the mounting part in a space-saving manner.
A further aspect of the invention is that the curing agent tank is designed as a replaceable unit, which can be fastened to a base part provided on the machine frame. The curing agent tank can be a commercially available IBC (intermediate bulk container) canister, which is used on construction sites anyway. If curing agent is available on the construction site in an IBC tank, in filling mode, the agent can be easily pumped from this tank into the tank located on the curing machine. Since the two tanks have the same filling volume, the one tank can be completely emptied in a pumping operation, and the other tank can be completely filled. A pumped transfer of curing agent is not necessary, however, since the curing agent tank is designed as a replaceable unit. Consequently, the empty tank can simply be replaced by a filled tank.
The at least one pump is preferably a centrifugal pump driven by a hydraulic motor, and/or the shut-off elements are preferably electromagnetically-actuatable shut-off elements. However, the pump can also be an electrically-driven pump, and the shut-off elements can also be hydraulically- or pneumatically-actuated shut-off elements.
To simplify manufacturing, individual assemblies of the sprayer can be pre-assembled units which can be placed on the machine frame and fastened to the machine frame.
An embodiment of the curing machine according to the invention is described in detail below with reference to the figures.
Shown are:
The curing machine 10 has an elongated machine frame 11, which is supported in the working direction A by lifting devices 12 on the left-hand side and by lifting devices 13A, 13B on the right-hand side, to which the left-hand ground engaging units 14A, 14B and right-hand ground engaging units 15A, 15B, e.g., crawler tracks, are fastened, so that the machine frame 11 is adjustable in height with respect to the concrete slab. Wheeled ground engaging units may also be used. The working width of the machine frame 11 is a multiple of the working depth.
The machine frame 11 has longitudinal beams 16 extending in the working direction A and transverse beams 17 extending transversely to the working direction, wherein the transverse beams 17 are telescopic for variable adjustment of the working width. The working width can also be increased by using additional frame elements (not shown).
The drive unit 18 of the curing machine 10 is arranged on the left-hand side of the machine frame 11 in the working direction A. In addition to the drive unit 18, there is a control console 19 with a control panel 19A. Drive unit 18 and control console 19 are arranged on a platform 20 of the machine frame 11, which can be accessed by the machine operator.
The curing machine 10 has a working device for applying texturing to the fresh concrete slab. This working device can comprise a device 21 for applying texturing in the transverse direction and/or a device (not shown) for applying texturing in working direction A, which devices can be activated individually.
Furthermore, the working device comprises a sprayer 23 for applying a liquid curing agent, e.g., a dispersion, to the fresh concrete slab, which device can comprise various individually activatable spraying units for applying a curing agent.
The curing agent is provided in a replaceable curing agent tank 29, which is arranged on the right-hand side of the machine frame 11 in the working direction A. The curing agent tank 29 is a conventional IBC (intermediate bulk container) canister having a filling volume of 1,000 L, which has a plastic tank 29A that is enclosed by a metal basket 29B. The plastic tank 29A has on the upper side an opening 29C, which is closed with a screw cap 29D, and has an outlet 29E at the bottom.
Furthermore, the sprayer 23 has a removable mixing unit 33 for mixing curing agent in the curing agent tank 29 and which can be inserted into the opening 29C of the curing agent tank 29 when the screw cap 29D has been unscrewed.
The structure and function of the sprayer 23 will be described below.
The sprayer 23 has a controller 35 and an operating unit 36 that works together with the controller. For each operating mode, the operating unit 36 has an operating element 36A, 36B, 36C, 36D—for example, a pushbutton, switch, or a button of a touchscreen. By actuating an operating element 36A, 36B, 36C, 36D, one of the above-mentioned operating modes is selected, wherein the respective operating mode is executed automatically.
The controller 35 is connected via control lines (not shown in
The hydraulic circuit diagram shows two spraying units 24, 27 each having two groups 24A, 24B, 27A, 27B of spray nozzles 25 for applying a curing agent. The groups 24A, 24B, 27A, 27B of spray nozzles 25 are each assigned a spray nozzle shut-off element 37A, 37B, 37C, 37D, e.g., a non-energized, spring-returned, electromagnetically-actuated 2/2-way valve, so that the supply of liquid to the spray nozzles 25 can be interrupted. By opening or closing the respective spray nozzle shut-off elements, curing agent can be applied to the fresh concrete slab by one of the spraying units 24, 27 over a specific working width. The spray nozzle shut-off elements are also referred to below as shut-off elements 8 (
The liquids are conveyed in the liquid system 34 by means of only a single hydraulic pump 38, which is driven by a single hydraulic motor 39. However, several pumps can also be provided. In order to operate the hydraulic motor 39, hydraulic fluid flows from a hydraulic fluid tank 40 to the hydraulic motor and from the hydraulic motor into the hydraulic fluid tank. For the sake of simplicity, the line sections 41 leading from the hydraulic fluid tank 40 to the hydraulic motor 39 are only partially shown in
The curing agent is provided in the replaceable curing agent tank 29, and in particular the IBC (intermediate bulk container) (
When the operating element 36A is actuated for the spraying mode B, the controller 35 opens the shut-off element 1 and the respective spray nozzle shut-off elements 8 (37A, 37B, 37C, 37D) as well as the shut-off element 3, and puts the hydraulic motor 39 of the pump 38 into operation, so that curing agent flows to the spray nozzles 25 of the respective nozzle group 24A, 24B, 27A, 27B. The shut-off element 7 is closed. Since the shut-off element 3 is open in spraying mode, the curing agent can flow back into the curing agent tank 29 if a pressure is exceeded.
In filling mode A, the curing agent tank 29 is filled with curing agent, wherein curing agent is provided with an external curing agent source 50, e.g., in an external curing agent tank—in particular, an IBC container. The curing agent flows, via a supply line path 51, from the external curing agent tank 50 into the internal curing agent tank 29 arranged on the machine frame 11. The supply line path 51 comprises a liquid line 52 which departs from the external curing agent tank 50 and leads to the liquid line 43A leading to the inlet of the pump 38, the liquid line 43A leading to the inlet of the pump 38 and the liquid line 48, which branches off from the liquid line 43B leading from the outlet of the pump 38, and leads to the curing agent tank 29. In filling mode A, the controller 35 puts the pump 38 into operation and opens the shut-off elements 6 and 7. The shut-off element 1 is closed (
When cleaning mode D is activated, a cleaning agent flows along a cleaning agent path 53. The cleaning agent is provided in a cleaning agent tank 54, wherein the cleaning agent can be warm water. A cleaning agent feed line 55 leads from the cleaning agent tank 54 to the liquid line 43A, leading to the inlet of the pump 38, and a cleaning agent discharge line 56, which leads back to the cleaning agent tank 54, branches off from the liquid line 49 connected to the overpressure connection of the pressure limiting valve 44. A shut-off element 2—in particular, a non-energized, spring-returned, electromagnetically-actuated 2/2-way valve—is interposed in the cleaning agent feed line 55, and a shut-off element 5—in particular, an electromagnetically-actuated 2/2-way valve, is interposed in the cleaning-agent discharge line 56. In cleaning mode D, the controller 35 puts the pump 38 into operation, and opens the shut-off elements 2, 5, 8 and leaves the shut-off elements 1, 3, 4, 6, 7 (
When mixing mode C is activated, curing agent circulates in a curing agent circulation path 57 in order to mix the curing agent in the curing agent tank 29. The mixing of the curing agent in the curing agent tank 29 is therefore not effected by the use of a stirrer, but by curing agent flowing through the tank.
The curing agent circulation path 57 comprises the liquid line 43A, leading to the inlet of the pump 38, and a line section of the liquid line 43B, leading from the outlet of the pump, a bypass line 58 which branches off from the liquid line 43B leading from the pump 38 and leads, via a line section of the cleaning agent discharge line 56, to the liquid line 49 connected to the overpressure connection of the pressure relief valve 44. A further shut-off element 4—in particular, a non-energized, spring-returned, electromagnetically-actuated 2/2-way valve—which is actuated by the controller 35, is interposed in the bypass line 57. In mixing mode C, the controller 35 puts the pump 38 into operation, and opens the shut-off elements 1, 3, 4 and leaves the shut-off elements 2, 5, 6, 7, 8 (
The controller 35 or the operating unit 36 can be configured such that only a single operating mode can be selected and thus activated. This avoids operating errors. However, it is also possible for several, i.e., at least two, operating modes to be able to be executed simultaneously, if this is to be possible.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2022 123 625.0 | Sep 2022 | DE | national |
