Hydraulic system, building material and / or thick material pump and method

Abstract

The invention relates to a hydraulic system (1) for driving a building material and / or thickener pump (50), the hydraulic system (1) having: a supply pressure section (3) and a low pressure section (4) for a hydraulic liquid (L); a controllable low-pressure limiting valve device (5) for variably setting a low-pressure value range of a low pressure (N) of the hydraulic fluid (L) in the low-pressure section (4); a controllable supply pressure limiting valve device (6) for variably setting a supply pressure value range of a supply pressure (S) of the hydraulic fluid (L) in the supply pressure section (3); and a control device (7) which is designed to jointly control the low-pressure limiting valve device (5) and the supply-pressure limiting valve device (6) in such a way that the low-pressure limiting valve device (5) and the supply-pressure limiting valve device (6) set a low-pressure value range and a supply-pressure value range in dependence on one another.

Description

Technical Field

[0001] This invention relates to a hydraulic system for driving a pump for building materials and / or thickeners. The invention also relates to such a pump for building materials and / or thickeners. Furthermore, the invention relates to a method for operating such a pump for building materials and / or thickeners. Summary of the Invention

[0002] The objective of this invention is to provide a hydraulic system for driving a pump of building materials and / or thickeners, a such pump of building materials and / or thickeners, and a method for operating such a pump of building materials and / or thickeners, having improved characteristics.

[0003] This task is addressed by the subject matter of the independent claims. Preferred embodiments are the subject matter of the dependent claims.

[0004] The hydraulic system according to the invention is used to drive a pump for building materials and / or thickeners. The pump can be driven by the hydraulic system to transport building materials and / or thickeners. Here, the hydraulic system has a supply pressure section and a low-pressure section for the hydraulic fluid. Furthermore, the hydraulic system has an adjustable pressure limiting valve device configured to variably set the low-pressure value range of the hydraulic fluid in the low-pressure section. Additionally, the hydraulic system has an adjustable supply pressure limiting valve device configured to variably set the supply pressure value range of the hydraulic fluid in the supply pressure section. The hydraulic system also has a regulating device. The regulating device is configured to jointly regulate the low-pressure limiting valve device and the supply pressure limiting valve device. Here, the regulating device is configured to jointly regulate the low-pressure limiting valve device and the supply pressure limiting valve device such that the low-pressure limiting valve device and the supply pressure limiting valve device interdependently set the low-pressure value range, especially the low pressure within the low-pressure value range, and the supply pressure value range, especially the supply pressure within the supply pressure value range. The hydraulic system can have a closed hydraulic circuit for the hydraulic fluid, wherein the closed hydraulic circuit includes a supply pressure section and a low-pressure section. Suitably, the hydraulic circuit of the hydraulic system has at least one hydraulic line, particularly a pipe and / or hose. A low-pressure limiting valve device and a supply pressure limiting valve device can be coupled to each other for joint regulation. Suitably, at least one of the low-pressure limiting valve device and the supply pressure limiting valve device can be electrically and / or hydraulically operated by means of a regulating device. Advantageously, the hydraulic system achieves demand-appropriate adaptation of the supply pressure and / or low pressure to enable particularly energy-efficient driving of building material and / or thick material pumps. In particular, by means of the hydraulic system, the supply pressure and / or low pressure can be reduced by correspondingly setting the low-pressure value range and / or the supply pressure value range to reduce power loss and thus minimize the energy consumption of the building material and / or thick material pumps.

[0005] Suitably, the low-pressure limiting valve device is configured to automatically and / or adjustably set the low-pressure value range, especially during operation of the hydraulic system, and especially during the operation of the building material and / or thick material pump. Alternatively or additionally, the supply pressure limiting valve device is suitably configured to automatically and / or adjustably set the supply pressure value range, especially during operation of the hydraulic system, and especially during the operation of the building material and / or thick material pump.

[0006] Advantageously, the hydraulic system according to the invention can achieve demand-oriented (i.e., adaptive) setting, in particular, reduction of the upper limit values ​​of the low-pressure range and / or the supply pressure range. The supply pump of the hydraulic system, used to supply the supply pressure range with hydraulic fluid having a supply pressure, can operate beyond and / or near the upper limit of the supply pressure range. In this way, demand-oriented energy consumption of the supply pump can be achieved, in particular, a reduction in the energy consumption of the supply pump, which can have a beneficial effect on the energy consumption of the hydraulic system. The supply pressure can be generated by means of the supply pump of the hydraulic system. Therefore, the supply pump can be configured to supply the hydraulic system with hydraulic fluid. The supply pressure range is, for example, 8 to 40 bar, particularly 8 to 34 bar.

[0007] The term “configuration” can be used as a synonym for the term “construction”.

[0008] The terms “including” or “contains” are used interchangeably and can be used as synonyms for the term “having”.

[0009] In this regard, “regulation” can mean “control” and / or “adjustment”.

[0010] Building materials may include, in particular, mortar, cement, self-leveling mortar, concrete, plaster and / or building bulk materials (e.g., sand, gravel and / or crushed stone). Additionally or alternatively, thick materials may include, in particular, slurry.

[0011] Suitably, the hydraulic system may have a container, particularly a tank, for storing hydraulic fluid. A supply pump may be configured to supply hydraulic fluid from the container into the supply pressure section. Additionally or alternatively, the supply pump may be a constant flow pump. Additionally or alternatively, the supply pump may be configured to directly and / or indirectly supply fluid into the supply pressure section.

[0012] In the design of this invention, the control device is configured to jointly control the low-pressure limiting valve device and the supply pressure limiting valve device according to at least one operating parameter of the hydraulic system and / or the hydraulic fluid. Here, the at least one operating parameter can be the drive state, drive flow rate, drive pressure, and / or drive speed. In particular, the drive state can be an active (i.e., driven) state or a passive (i.e., undriven) drive state, particularly for the building material and / or thickener pump. Additionally or alternatively, the drive flow rate and / or drive pressure can each have, in particular, variable values ​​or magnitudes, and / or operating parameters of the hydraulic fluid. Furthermore, additionally or alternatively, the drive speed can have, in particular, variable values ​​or magnitudes, and / or operating parameters of the supply pump and / or drive motor (if present). The operating pressure (which can also be referred to as "high pressure" relative to low pressure) is, for example, 0 to 1000 bar, particularly 0 to 400 bar.

[0013] In the design of this invention, the low-pressure limiting valve device and the supply pressure limiting valve device can jointly perform hydraulic regulation, especially pre-control. Here, the regulation device has, in particular, a single, electrically adjustable regulating valve device. The regulating valve device is configured for joint hydraulic regulation, especially pre-control of the low-pressure limiting valve device and the supply pressure limiting valve device. The electrically adjustable regulating valve device can be a pre-control valve device. The regulating valve device can be fluidly connected to a hydraulic control line, wherein the low-pressure limiting valve device and the supply pressure limiting valve device are fluidly connected to each other via the same control line.

[0014] In the design of this invention, the low pressure range is from a minimum of 2.5 bar, especially a minimum of 5 bar, especially a minimum of 10 bar, especially a minimum of 15 bar to a maximum of 40 bar, especially a maximum of 35 bar, especially a maximum of 30 bar, especially a maximum of 25 bar. The low pressure range and the supply pressure range can be coordinated such that the low pressure is, for example, 1 to 4 bar lower than the supply pressure.

[0015] In another embodiment of the invention, the low-pressure limiting valve device has an adjustable proportional pressure limiting valve configured to continuously set the low-pressure value range. In particular, the proportional pressure limiting valve of the low-pressure limiting valve device is configured to automatically set the low-pressure value range. In particular, the proportional pressure limiting valve of the low-pressure limiting valve device can be adjusted by means of a regulating device. Alternatively or additionally, the supply pressure limiting valve device has an adjustable proportional pressure limiting valve configured to continuously set the supply pressure value range. In particular, the proportional pressure limiting valve of the supply pressure limiting valve device is configured to automatically set the supply pressure value range. In particular, the proportional pressure limiting valve of the supply pressure limiting valve device can be adjusted by means of a regulating device.

[0016] Suitablely, the proportional pressure limiting valve of the low-pressure limiting valve device and / or the supply pressure limiting valve device can be a proportional pressure control valve and / or referred to as a proportional pressure control valve.

[0017] In another embodiment of the invention, the hydraulic system has a variablely adjustable, and in particular, settable, drive pump. The drive pump is configured to generate a variable drive flow rate of hydraulic fluid with a variable drive pressure in at least one drive pressure section of the hydraulic system. Furthermore, the hydraulic system has at least one hydraulically based, and in particular electrically operable, actuator configured to variablely adjust, and in particular, set the drive pump by a variable set pressure of the hydraulic fluid. Here, a supply pressure section is configured to hydraulically supply the at least one actuator with hydraulic fluid having a supply pressure adjusted for the control pressure. Here, a control device is configured, in particular, to control the at least one actuator according to at least one operating parameter, such that the at least one actuator, in particular, variably adjusts the drive pump to generate a variable drive flow rate of hydraulic fluid with a variable drive pressure in at least one drive pressure section.

[0018] In particular, the drive pressure section can be different from the supply pressure section. Specifically, the supply pressure section is configured to supply hydraulic fluid into the drive pressure section by means of at least one supply check valve in the hydraulic system. Therefore, the supply pump can be configured to supply fluid indirectly (i.e., indirectly) into the drive pressure section.

[0019] In another embodiment of the invention, the drive pump is an axial piston pump with a swashplate that can be variably adjusted. Here, at least one actuator is configured to variably adjust the swashplate. In particular, the axial piston pump has a variably adjustable, and especially set, displacement. Here, the actuator can be configured to variably adjust the displacement, especially automatically. In particular, the swashplate's swing angle can depend on operating parameters. In particular, the control device can be configured to automatically determine and / or measure and / or calculate the swing angle, especially its value, based on at least one operating parameter.

[0020] In another embodiment of the invention, the hydraulic system has at least one drive cylinder and an associated drive piston, particularly guided within the drive cylinder. Here, the drive pump is configured to generate a drive flow of hydraulic fluid by variably moving at least one drive piston, particularly within the drive cylinder. In particular, the hydraulic system may have at least one pump line. The drive pump and drive cylinder may be connected by means of the pump line for the flow of hydraulic fluid, particularly between the drive pump and the drive cylinder. Additionally or alternatively, the drive piston may be configured to apply pressure using the hydraulic fluid. Furthermore, additionally or alternatively, a control device may be configured to control the movement of the drive piston, particularly automatically, based on at least one operating parameter.

[0021] In another embodiment of the invention, the hydraulic system has at least two drive cylinders and at least two correspondingly associated drive pistons, particularly guided within the respective drive cylinders. Furthermore, the hydraulic system has a swing line for the hydraulic fluid. The drive pump and the two drive cylinders can be configured into a closed drive circuit for the hydraulic fluid via the swing line. The two drive pistons are coupled, particularly in opposite phases, via the swing line. In particular, the two drive cylinders can be connected via the swing line for the flow of hydraulic fluid, particularly between the drive cylinders. Additionally or alternatively, the hydraulic system may have at least two pump lines. The drive pump and the two drive cylinders can be configured into a closed drive circuit for the hydraulic fluid via the swing line and the two pump lines. In particular, one of the drive pump and the two drive cylinders can be connected via one of the two pump lines for the flow of hydraulic fluid, particularly between the drive pump and the drive cylinder. The other of the drive pump and the two drive cylinders can be connected via the other of the two pump lines for the flow of hydraulic fluid, particularly between the drive pump and the drive cylinder. Additionally or alternatively, the drive pump or closed drive circuit may have a high-pressure side and a low-pressure side, especially during the operation of the hydraulic system, particularly during the driving of pumps for building materials and / or thick materials. In particular, the drive pressure—as described above—may be referred to as high pressure, especially high pressure on the high-pressure side. Low pressure may be generated or produced by a supply pump. The drive pressure or high pressure, or its value, may be greater than the low pressure, or its value. In particular, a “closed drive circuit” may refer to the flow of hydraulic fluid from the drive pump (especially its high-pressure side) through a pump connection, a drive cylinder, a swing connection, another drive cylinder, and another pump connected to the drive pump (especially its low-pressure side).

[0022] In another embodiment of the invention, the low-pressure limiting valve device is configured to flush hydraulic fluid out of a low-pressure section by variably setting a low-pressure value range. Alternatively or additionally, the supply pressure limiting valve device is configured to flush hydraulic fluid out of a supply pressure section by variably setting a supply pressure value range. In particular, the hydraulic fluid can be flushed to prevent it from leaving the low-pressure range and / or supply pressure range at the upper limit of the low-pressure range and / or supply pressure range.

[0023] In another embodiment of the invention, the hydraulic system has at least one measuring sensor configured to measure at least one characteristic of the hydraulic system and / or the hydraulic fluid, particularly pressure. Here, the control device is configured to determine at least one operating parameter based on the measured characteristic.

[0024] The building material and / or thickener pump according to the invention includes a building material and / or thickener conveying device. The building material and / or thickener conveying device is configured for conveying building materials and / or thickeners. Furthermore, the building material and / or thickener pump has a hydraulic system according to the invention as described above. Here, the hydraulic system is configured to drive the building material and / or thickener conveying device. The advantages of the hydraulic system according to the invention described above also apply to the building material and / or thickener pump according to the invention having such a hydraulic system.

[0025] Suitable, building material and / or thick material pumps can be constructed as mobile devices, especially vehicle-mounted building material and / or thick material pumps.

[0026] The method according to the invention is used to operate the building material and / or thickener pump according to the invention as described above. Therefore, the building material and / or thickener pump according to the invention can be operated according to the method according to the invention. The method includes step a), according to which the drive flow rate and / or drive pressure of the hydraulic fluid in the drive pressure section of the hydraulic system is changed, in particular, by adjusting the drive pump of the variably adjustable hydraulic system. Furthermore, the method includes step b), according to which the upper limit of the low-pressure range is set to a predetermined maximum value if the time-varying rate of change of the drive flow rate and / or drive pressure is greater than a predetermined threshold. Furthermore, the method includes step c), according to which the upper limit of the low-pressure range is reduced if the time-varying rate of change of the drive flow rate and / or drive pressure is equal to or less than a predetermined threshold. In this way, the low pressure can be variably set at a particularly energy-saving level during the operation of the building material and / or thickener pump.

[0027] In the design of this invention, and particularly the method according to the invention, the drive flow rate is changed oscillatingly, especially when passing through zero. This allows for counter-phase adjustment of the two drive pistons in the slave drive cylinder of the building material and / or thick material pump.

[0028] In particular, the building material and / or thick material pump, especially the building material and / or thick material pump, may have at least one, especially variable, conveying parameter, which in particular has a value or quantity. In particular, the at least one conveying parameter may be a conveying state, a conveying flow rate, and / or a conveying pressure. Additionally or alternatively, at least one operating parameter may depend on at least one conveying parameter and / or must have a predetermined or desired value to achieve, in particular, a conveying parameter desired by the user. In particular, the drive state may depend on the conveying state, the drive flow rate may depend on the conveying flow rate, and / or the drive pressure may depend on the conveying pressure (if present). In other words, the control unit may be configured to determine or measure, in particular calculate, at least one operating parameter or its value, in particular automatically based on at least one conveying parameter. Furthermore, additionally or alternatively, the control unit may have an operating panel for operating the building material and / or thick material pump of the hydraulic system, in particular an input device for user input or user selection of at least one conveying parameter or its value. Attached Figure Description

[0029] Other advantages and features of the invention will become apparent from the claims and the following description of preferred embodiments of the invention as illustrated in the accompanying drawings. Herein, the same reference numerals denote the same or similar or functionally identical components.

[0030] It goes without saying that the features mentioned above and described below can be used not only in the corresponding combinations given, but also in other combinations or individually, without departing from the scope of the invention.

[0031] The only Figure 1 The diagram schematically illustrates a circuit diagram of an embodiment of a building material and / or thick material pump according to the invention, wherein the building material and / or thick material pump has an embodiment of a hydraulic system according to the invention, when performing a method for operating a building material and / or thick material pump implemented according to the invention. Detailed Implementation

[0032] The building material and / or thickener pump 50 according to the invention includes a building material and / or thickener conveying device 51. The building material and / or thickener conveying device 51 is configured to convey building materials and / or thickeners. Furthermore, the building material and / or thickener pump 50 has a hydraulic system 1 according to the invention, which is configured to drive the building material and / or thickener conveying device 51. The building material and / or thickener pump 50 can be driven by driving the building material and / or thickener conveying device 51. Accordingly, the hydraulic system 1 is configured to drive the building material and / or thickener pump 50.

[0033] The hydraulic system 1 has a supply pressure section 3 and a low-pressure section 4 for the hydraulic fluid L. The supply pressure section 3 and the low-pressure section 4 can be components of a closed hydraulic circuit for the hydraulic fluid L in the hydraulic system 1.

[0034] Furthermore, the hydraulic system 1 has an adjustable low-pressure limiting valve device 5. The adjustable low-pressure limiting valve device 5 is used to variably set the low-pressure value range of the low-pressure N of the hydraulic fluid L in the low-pressure section 4.

[0035] Furthermore, the hydraulic system 1 has an adjustable supply pressure limiting valve device 6. The adjustable supply pressure limiting valve device 6 is used to variably set the supply pressure range of the hydraulic fluid L in the supply pressure zone 3.

[0036] Furthermore, the hydraulic system 1 includes a control device 7. Here, the control device 7 is configured to jointly control the low-pressure limiting valve device 5 and the supply pressure limiting valve device 6, such that the low-pressure limiting valve device 5 and the supply pressure limiting valve device 6 interdependently set the low-pressure range and the supply pressure range. The low-pressure limiting valve device 5 and the supply pressure limiting valve device 6 can be coupled together for joint control.

[0037] Hydraulic system 1 currently includes a supply pump 19 configured to supply pressure section 3 with hydraulic fluid having a supply pressure S. Furthermore, hydraulic system 1 currently includes a reservoir 20, particularly a storage container or tank, for hydraulic fluid L. The supply pump 19 can be supplied with hydraulic fluid L from the reservoir 20. For example, hydraulic system 1 includes a supply check valve 21 that can connect the supply pressure section 3 to the low-pressure section 4, particularly in a unidirectional fluid-conducting manner. Additionally, hydraulic system 1 currently includes a switching flush valve 22 to which the low-pressure section 4 is fluid-conductingly connected. The switching flush valve 22 can be adjustably configured to fluid-conductingly connect the low-pressure section 4 to a low-pressure limiting valve device 5.

[0038] For example, hydraulic system 1 has a stopcock 23 by means of which the supply of hydraulic fluid L to the sway oil relief valve 24 of hydraulic system 1 can be set, in particular, blocked. Furthermore, hydraulic system 1 currently has a sway oil relief throttle valve 25, which can be supplied with hydraulic fluid L by means of another sway oil relief valve 24. Additionally, hydraulic system 1 currently has a flushing line 26, which may be part of the low-pressure section 4 and is configured to fluidly connect the low-pressure section 4 to the switching flushing valve 22.

[0039] Furthermore, the hydraulic system 1 currently has control lines 27, which are used to regulate the switching flush valve 22, the low-pressure limiting valve device 5, and the supply pressure limiting valve device 6, respectively. For example, the hydraulic system 1 has a set pressure line 28 for regulating the actuator 13 of the hydraulic system 1. The hydraulic system 1 currently has two control lines 27, especially hydraulic, for controlling the switching flush valve 22, especially automatically.

[0040] For example, the control device 7 is configured to jointly control the low-pressure limiting valve device 5 and the supply pressure limiting valve device 6 based on at least one operating parameter B of the hydraulic system 1. Alternatively or additionally, the control device 7 is configured to jointly control the low-pressure limiting valve device 5 and the supply pressure limiting valve device 6 based on at least one operating parameter B of the hydraulic fluid L. Here, the at least one operating parameter B is currently the drive state, drive flow rate, drive pressure A, and / or drive speed.

[0041] The supply pressure S can be generated by means of a supply pump 19 in the hydraulic system 1. The supply pump 19 is configured to supply hydraulic fluid L to the hydraulic system 1. The supply pressure S ranges from, for example, 8 to 40 bar, particularly 8 to 34 bar. The working pressure A (which can also be referred to as "high pressure" relative to the low pressure) ranges from, for example, 0 to 1000 bar, particularly 0 to 400 bar. The low pressure N can be 1 to 4 bar lower than the supply pressure S. For example, the lower limit of the low pressure range is 2.5 bar, particularly 5 bar, particularly 10 bar, particularly 15 bar. The upper limit of the low pressure range can be, for example, 40 bar, particularly 35 bar, particularly 30 bar, particularly 25 bar.

[0042] For example, the low-pressure limiting valve device 5 and the supply pressure limiting valve device 6 can jointly perform hydraulic regulation. Currently, the low-pressure limiting valve device 5 and the supply pressure limiting valve device 6 can jointly perform hydraulic pre-control. Here, the regulating device 7, for example, has an electrically adjustable regulating valve device 8. The regulating device 7 currently has a single electrically adjustable regulating valve device 8. The regulating valve device 8 is configured, for example, for jointly hydraulically regulating the low-pressure limiting valve device 5 and the supply pressure limiting valve device 6. Currently, the regulating valve device 8 is configured for jointly hydraulically pre-controlling the low-pressure limiting valve device 5 and the supply pressure limiting valve device 6.

[0043] The electrically adjustable control valve device 8 can be a pre-control valve device. The control valve device 8 can be fluidly connected to one of the control lines 27, wherein the low-pressure limiting valve device 5 and the supply pressure limiting valve device 6 are fluidly connected to each other via the same control line 7.

[0044] The low-pressure limiting valve device 5 currently has an adjustable proportional pressure limiting valve 9. The adjustable proportional pressure limiting valve 9 of the low-pressure limiting valve device 5 is configured, for example, to continuously set the low-pressure value range. Alternatively or additionally, the supply pressure limiting valve device 6—as is currently present—has, in particular, an additional adjustable proportional pressure limiting valve 10. The adjustable proportional pressure limiting valve 10 of the supply pressure limiting valve device 6 is configured, for example, to continuously set the supply pressure value range.

[0045] For example, the hydraulic system 1 has a variablely adjustable drive pump 11. The variablely adjustable drive pump 11 is currently configured to generate a variable drive flow rate of hydraulic fluid L with a variable drive pressure A in at least one drive pressure section 12 of the hydraulic system 1. For example, the hydraulic system 1 has at least one hydraulically based actuator 13 configured to variablely adjust the drive pump 11 by means of a variable set pressure of the hydraulic fluid L. Currently, there are two such hydraulically based actuators 13. Here, the supply pressure section 3 is configured, for example, to hydraulically supply at least one actuator 13 with hydraulic fluid L having a supply pressure S set for the set pressure. For example, the control device 7 is configured to control at least one actuator 13 such that at least one actuator 13 adjusts the drive pump 11 to generate a variable drive flow rate of hydraulic fluid L with a variable drive pressure A in at least one drive pressure section 12. Currently, the control device 7 is configured to control at least one actuator 13 according to at least one operating parameter B.

[0046] Currently, the drive pump 11 is an axial piston pump 14 with a swashplate that can be variably adjusted. Here, at least one actuator 13 is configured, for example, to variably adjust the swashplate.

[0047] For example, the hydraulic system 1 has at least one drive cylinder 15 and an associated drive piston 16. Here, the drive pump 11 is configured to generate a drive flow of hydraulic fluid L by variably moving at least one drive piston 16. Currently, the hydraulic system 1 has two drive cylinders 15 and corresponding associated drive pistons 16, which are coupled to each other by means of a swing line 17 for the hydraulic fluid L.

[0048] For example, the low-pressure limiting valve device 5 is configured to flush hydraulic fluid L out of the low-pressure section 4 by variably setting a low-pressure value range. Alternatively or additionally, the supply pressure limiting valve device 6—as is present—is configured to flush hydraulic fluid L out of the supply pressure section 3 by variably setting a supply pressure value range.

[0049] The hydraulic system 1 may include at least one measuring sensor 18 configured to measure at least one characteristic, particularly pressure, of the hydraulic system 1 and—optionally or additionally—the hydraulic fluid L. Here, the control device 7 is configured to determine at least one operating parameter B based on the measured characteristic. In this way, closed-loop regulation of the low-pressure limiting valve device 5 and / or the supply pressure limiting valve device 6 can be achieved by feeding back the measured characteristic via the operating parameter B determined therefrom.

[0050] Currently, the building materials and / or thickener pump 50 operates according to the method according to the invention. The method includes step a), according to which the drive flow rate of the hydraulic fluid L in the drive pressure section 12 of the hydraulic system 1 and—optionally or additionally—the drive pressure A are changed. Currently, the drive flow rate in the drive pressure section 12 and—optionally or additionally—the drive pressure A are changed by adjusting the drive pump 11, which can be variably adjusted. Furthermore, the method includes step b), according to which—if the time rate of change (especially the first time derivative) of the drive flow rate and—optionally or additionally—the drive pressure A is greater than a predetermined threshold—the upper limit of the low-pressure range is set to a predetermined maximum value. Furthermore, the method includes step c), according to which—if the time rate of change of the drive flow rate and / or the drive pressure A is equal to or less than a predetermined threshold—the upper limit of the low-pressure range is reduced. Here, the drive flow rate can be changed oscillatingly (e.g., as currently done in the case of passing zero).

[0051] For example, the drive pump 11 has a high-pressure side and a low-pressure side, which are periodically exchanged during the operation of the hydraulic system 1 and / or the building material and / or thickener pump 50. For example, the drive pressure A is above the upper limit of the low-pressure range. If in Figure 1 If the medium- and high-pressure side is located above, then the low-pressure side is located below, and vice versa. This is indicated by the diagonal line between the N and A labels in the attached diagram. If in Figure 1 With the medium- and high-pressure side located above, hydraulic fluid L with driving pressure A flows from the drive pump 11 to the... Figure 1 The drive cylinder 15 is shown in the lower center. Here, the drive pump 11 and the... Figure 1 The hydraulic connection between the drive cylinders 15 shown in the lower middle section at least partially forms the drive pressure section 12. Therefore, in Figure 1 The drive piston 16 shown in the lower middle section can... Figure 1 The fluid moves to the right. Hydraulic fluid L, especially hydraulic fluid L with swing pressure, flows through the swing line 17 from the... Figure 1 The drive cylinder 15 shown in the lower middle section flows to the... Figure 1The drive cylinder 15 is shown in the upper middle section. Here, the swing pipe 17 and the drive cylinder 15 can, in particular, at least partially form the swing pressure section. Therefore, in Figure 1 The drive piston 16 shown in the upper middle section is in Figure 1 Move from center to left. Hydraulic fluid L with low pressure N flows from... Figure 1 The flow from the drive cylinder 15 shown in the upper middle section flows to the drive pump 11. Here, the drive pump 11 and the... Figure 1 The connection between the drive cylinders 15 shown in the upper middle section can, in particular, at least partially form the low-pressure section 4. Here, the supply pressure section 3 is achieved, particularly by means of... Figure 1 The supply check valve 21 shown in the upper middle section supplies the low-pressure section 4.

[0052] Currently, if the drive piston 16 reaches its end position, the high-pressure side and low-pressure side of the drive pump 11 are switched. Therefore, the high-pressure side... Figure 1 The middle is located above and the low-pressure side is located below. Therefore, in Figure 1 The drive piston 16 shown in the lower middle section is in Figure 1 The piston moves to the left, and the drive piston 16 shown above moves to the right.

[0053] For example, hydraulic fluid L can be flushed out of hydraulic system 1 by means of low-pressure limiting valve device 5 and / or supply pressure limiting valve device 6, especially into reservoir 20.

[0054] For example, a portion of the hydraulic fluid L flows out of the supply pressure section 3 and into the low pressure section 4. Another portion of the hydraulic fluid L can be flushed out from the supply pressure section 3.

[0055] For example, a portion of the hydraulic fluid L flows from the low-pressure section 4 to the drive pump 11. Another portion of the hydraulic fluid L can be flushed out from the low-pressure section 4.

[0056] Currently, the low-pressure section 4 and the low-pressure limiting valve device 5 are connected via a switching flushing valve 22 for the flow of hydraulic fluid L. If in Figure 1 If the medium-low pressure section 4 is arranged at the top, the hydraulic fluid L can flow from the low pressure section 4 to the low pressure limiting valve device 5 through the switching flushing valve 22.

[0057] For example, the hydraulic system 1 has two flushing lines 26 for hydraulic fluid L. The low-pressure section 4 and the drive pressure section 12 are respectively connected to a switching flushing valve 5 via one of the flushing lines 26. Here, the switching flushing valve 5 is configured, for example, to connect such a flushing line 26 (which has a lower pressure than the other flushing line 26) to a low-pressure limiting valve device 5, especially for the flow of hydraulic fluid L from the respective flushing line 26 to the low-pressure limiting valve device 5.

[0058] The building material and / or thickener conveying device 51, for example, has at least one, particularly two, conveying cylinders and, particularly two associated, conveying pistons arranged within the conveying cylinders. In particular, at least one conveying cylinder is configured for conveying building materials and / or thickeners. At least one conveying cylinder may be configured to apply pressure to the building materials and / or thickeners. The hydraulic system 1 may have at least one, particularly two, piston rods. At least one piston rod may be configured to motion couple or transmit at least one drive piston 16 to at least one conveying piston. In particular, at least one piston rod is fastened to at least one drive piston 16 or to at least one conveying piston. Furthermore, the building material and / or thickener conveying device 51 may have a pipe reversing system.

[0059] Therefore, the building material and / or thickener conveying device 51 can have a conveying cylinder with a variable-volume conveying chamber. To change the volume of the conveying chamber, particularly in reverse, adjustable conveying pistons can be assigned to the conveying cylinder. Furthermore, the building material and / or thickener conveying device 51 can include an S-shaped pipe reversing device, particularly an S-shaped pipe, which is fluidly connected at one end to a pressure pipe serving as the outlet of a building material and / or thickener pump. The pipe reversing device can be arranged in a storage chamber for storing building materials and / or thickeners, which can be filled from above using building materials and / or thickeners. Here, the pipe reversing device can be rotatably supported at one end at the pressure pipe within the storage chamber. The variable-volume conveying chamber can lead into the storage chamber. The pipe reversing device can oscillate within the storage chamber relative to the conveying chamber such that the pipe reversing device can be alternately connected in communication with one piece of building material and / or thickener within the conveying chamber. In this way, through the interaction of the oscillation of the pipe diverter and the volume change of the delivery chamber, the building materials and / or thick materials in the storage chamber can be alternately drawn in by means of the delivery chamber and pumped out through the pipe diverter via the pressure pipe.

[0060] The present invention can provide an advantageous hydraulic system 1 for a building material and / or thick material pump 50 and an advantageous building material and / or thick material pump 50 having such a hydraulic system 1, wherein the hydraulic system or the building material and / or thick material pump has improved characteristics, in particular achieving energy or power savings.

Claims

1. A hydraulic system (1) for driving a pump (50) for building materials and / or thick materials, wherein, The hydraulic system (1) has: - Supply pressure section (3) and low pressure section (4) for hydraulic fluid (L), - An adjustable low-pressure limiting valve device (5) for variably setting the low-pressure value range of the hydraulic fluid (L) in the low-pressure section (4) (N). - An adjustable supply pressure limiting valve device (6) for variably setting the supply pressure range of the hydraulic fluid (L) supply pressure (S) in the supply pressure zone (3), and - A control device (7) configured to jointly control the low-pressure limiting valve device (5) and the supply pressure limiting valve device (6) such that the low-pressure limiting valve device (5) and the supply pressure limiting valve device (6) mutually dependently set the low-pressure value range and the supply pressure value range.

2. The hydraulic system (1) according to the preceding claims, - in, The control device (7) is configured to jointly control the low-pressure limiting valve device (5) and the supply pressure limiting valve device (6) based on at least one operating parameter (B) of the hydraulic system (1) and / or the hydraulic fluid (L). - In particular, the at least one operating parameter (B) is drive state, drive flow rate, drive pressure (A) and / or drive speed.

3. The hydraulic system (1) according to any one of the preceding claims, - in, The low-pressure limiting valve device (5) and the supply pressure limiting valve device (6) can work together to perform hydraulic regulation, especially pre-control. - The control device (7) has a unique electrically controllable control valve device (8), wherein the control valve device (8) is configured for joint hydraulic control, in particular for pre-controlling the low-pressure limiting valve device (5) and the supply pressure limiting valve device (6).

4. The hydraulic system (1) according to any one of the preceding claims, in, The low pressure ranges from a minimum of 2.5 bar, especially a minimum of 5 bar, especially a minimum of 10 bar, especially a minimum of 15 bar to a maximum of 40 bar, especially a maximum of 35 bar, especially a maximum of 30 bar, especially a maximum of 25 bar.

5. The hydraulic system (1) according to any one of the preceding claims, - in, The low-pressure limiting valve device (5) has an adjustable proportional pressure limiting valve (9), which is configured to continuously set the low-pressure value range, and / or - The supply pressure limiting valve device (6) has an adjustable proportional pressure limiting valve (10) configured to continuously set the supply pressure value range.

6. The hydraulic system (1) according to any one of the preceding claims, having - A variablely adjustable drive pump (11), the drive pump being configured to generate a variable drive flow rate of hydraulic fluid (L) having a variable drive pressure (A) in at least one drive pressure section (12) of the hydraulic system (1), and - At least one hydraulically based actuator (13) configured to variably adjust the drive pump (11) by means of a variable set pressure of hydraulic fluid (L). - in, The supply pressure section (3) is configured to hydraulically supply the at least one actuator (13) with hydraulic fluid (L) having a supply pressure (S) set for the set pressure. - wherein the control device (7) is configured, in particular, to control the at least one actuator (13) according to at least one operating parameter (B) such that the at least one actuator (13) adjusts the drive pump (11) to generate a variable drive flow rate of hydraulic fluid (L) with a variable drive pressure (A) in the at least one drive pressure section (12).

7. The hydraulic system (1) according to the preceding claims, - in, The drive pump (11) is an axial piston pump (14) with a variablely adjustable swashplate. - wherein the at least one actuating element (13) is configured to variably adjust the swashplate.

8. The hydraulic system (1) according to any one of the preceding two claims, having - At least one drive cylinder (15) and an associated drive piston (16), - in, The drive pump (11) is configured to generate a drive flow of hydraulic fluid (L) by variably moving the at least one drive piston (16).

9. The hydraulic system (1) according to the preceding claim, having - At least two drive cylinders (15) and corresponding associated drive pistons (16), and - Swing line (17) for hydraulic fluid (L), - in, The two drive pistons (16) are coupled by means of the swing pipe (17).

10. The hydraulic system (1) according to any one of the preceding claims, in, The low-pressure limiting valve device (5) is configured to flush hydraulic fluid (L) out of the low-pressure section (4) by variably setting the low-pressure value range, and / or wherein the supply pressure limiting valve device (6) is configured to flush hydraulic fluid (L) out of the supply pressure section (3) by variably setting the supply pressure value range.

11. The hydraulic system (1) according to any one of the preceding claims, comprising: - At least one measuring sensor (18) configured to measure at least one characteristic, particularly pressure, of the hydraulic system (1) and / or hydraulic fluid (L). - in, The control device (7) is configured to determine at least one operating parameter (B) based on the measured characteristics.

12. A building material and / or thick material pump (50) comprising: - A building materials and / or thickener conveying device (51), said building materials and / or thickener conveying device being configured for conveying building materials and / or thickeners, - The hydraulic system (1) according to any one of the preceding claims is configured to drive the building material and / or thick material conveying device (51).

13. A method for operating a building material and / or thickener pump (50) according to the preceding claims, in, The method comprises the following steps: a) In particular, by adjusting the drive pump (11) of the hydraulic system (1) which can be variably adjusted, the drive flow rate and / or drive pressure (A) of the hydraulic fluid (L) in the drive pressure section (12) of the hydraulic system (1) can be changed. b) If the rate of change of the driving flow rate and / or driving pressure (A) over time is greater than a predetermined threshold: set the upper limit of the low pressure range to the predetermined maximum value. c) If the time rate of change of the driving flow rate and / or driving pressure (A) is equal to or less than the predetermined threshold: reduce the upper limit of the low pressure range.

14. The method according to the preceding claims, in, The driving flow rate is changed oscillatingly, especially when passing through zero.

Images