Hydraulic systems with direct mounting of switching valve on hydrostatic machine with closed circuit

Abstract

A hydraulic system with a closed hydraulic circuit, comprising a switching valve (2) and a hydrostatic machine (1), wherein the hydraulic system supplies two or more consumers and wherein the hydraulic system is configured for switching between the two or more consumers.

Description

[0001] Hydraulic systems with direct mounting of switching valve on hydrostatic machine with closed circuit

[0002] Technical field

[0003] The present invention relates to hydraulic systems of mobile and stationary machines with a closed hydraulic circuit.

[0004] background

[0005] Hydraulic systems in mobile and stationary machines, especially systems with closed hydraulic circuits, are used, for example, in mobile shredders, construction machinery, forestry equipment, material handling machines, and special-purpose vehicles. These machines often use hydrostatic drives for power transmission, in which axial or radial piston variable displacement pumps and motors, as well as gear, orbital, and vane pumps or motors, are operated in a closed circuit.

[0006] A characteristic of closed hydraulic circuits is that the oil from the consumer flows directly back to the hydrostatic machine. This offers particular advantages in applications where the load pushes (e.g., downward travel in drive systems) or pulls (e.g., winches). In these applications, a hydraulic motor acts as a pump, which in turn is powered by the drive motor (e.g., a diesel engine). This means that braking can be achieved with a closed circuit.

[0007] Axial or radial piston variable displacement pumps and motors can collectively be referred to as axial or radial piston units.

[0008] In existing applications, for example, 6 / 2-way diverter valves are used to redirect the oil or fluid flow of a hydrostatic machine between different consumers. This allows a single hydrostatic machine to be used for different operating modes, such as driving shredding shafts or track drives in mobile shredders. Typically, these diverter valves are mounted separately from the hydrostatic machine and connected via flexible high-pressure lines. However, this design has several disadvantages.

[0009] The separate arrangement of the hydrostatic unit and the changeover valve necessitates large bending radii for the high-pressure lines and restricts service accessibility, resulting in increased space requirements within the already limited machine footprint. Flexible high-pressure lines are also costly to manufacture, install, and maintain. Furthermore, they must be regularly inspected and replaced due to wear and safety requirements. Longer line runs and additional mounting interfaces further increase fluid friction and the risk of leaks. These issues lead to increased operating costs, reduced machine availability (particularly due to poorer maintainability), and potential safety hazards.

[0010] The present invention addresses the aforementioned challenges through an improved design that reduces space requirements, increases efficiency, and lowers operating costs. The aim is to create a compact, reliable, and cost-effective solution that retains the advantages of existing systems while eliminating the aforementioned disadvantages.

[0011] Specifically, the invention provides a hydraulic system with a changeover valve directly mounted to the hydrostatic machine in a closed circuit. This design connects the two components directly, eliminating the need for flexible high-pressure lines. The connecting channels are arranged so that the consumer working ports of the hydrostatic machine and the changeover valve are connected without additional external piping. This optimizes installation space, reduces assembly costs, and significantly minimizes the risk of leaks and energy losses.

[0012] Summary of the invention

[0013] The invention relates to hydraulic systems and shredder-comprising hydraulic systems with a closed hydraulic circuit, including at least one hydrostatic machine and a switching valve.

[0014] The present disclosure provides, in a first aspect, a hydraulic system with a closed hydraulic circuit, comprising a switching valve and a hydrostatic machine directly or indirectly rigidly connected thereto, wherein the hydraulic system supplies two or more consumers and wherein the hydraulic system is configured to switch between the two or more consumers.

[0015] This advantageously eliminates the need for high-pressure connections for the hydraulic fluid, which would have large bending radii, and reduces the space required for the apparatus. Furthermore, the elimination of continuous lines reduces the risk of leaks and improves maintainability.

[0016] After implementation of the device of the first aspect, the device can be designed such that the switching of all consumer working connections between individual consumers only takes place when the consumers are at a standstill, and a complete switching is secured by a switching position monitoring.

[0017] Designing it as a passive element increases safety.

[0018] Particularly when used with large and heavy machines, especially industrial mobile or stationary shredders, it is important that only one consumer is operated.

[0019] Following an implementation of the device of the first aspect, the device can be designed such that the hydraulic system has an adapter block between the hydrostatic machine and the changeover valve, and wherein the adapter block comprises:

[0020] Connection channels for fluid connection between the consumer working ports of the hydrostatic machine and the switching valve,

[0021] at least one fastening device designed so that the adapter block can be mounted without gaps on the consumer working ports of the hydrostatic machine and the changeover valve,

[0022] Sealing materials that are arranged between the flange surfaces of the adapter block and the consumer working ports of the hydrostatic machine and the changeover valve to seal the hydraulic connections.

[0023] The adapter block is used in particular to connect hydrostatic machines and switching valves that do not fit together directly, without having to use high-pressure lines with increased space requirements and poorer maintainability.

[0024] After implementation of the device of the first aspect, the device can be designed such that the adapter block has a first adapter block and a second adapter block, wherein the first adapter block with the hydrostatic machine and the second adapter block with the changeover valve can be mounted gap-free at the respective consumer working ports of the hydrostatic machine and the changeover valve, and wherein the first and second adapter ports have connections at which the first and second adapter ports can be connected to each other without gaps.

[0025] The two-part adapter block facilitates the connection of the hydrostatic machine and the changeover valve and can standardize the connection options of the components.

[0026] After implementing the device of the first aspect, the device can be designed such that the switching valve is a 6 / 2-way switching valve, a 6 / 3-way switching valve, two 3 / 2-way switching valves, two 4 / 3-way switching valves or an 8 / 3-way switching valve.

[0027] Various types of switching valves are available, all of which have in common that, particularly for safety reasons, they can each guarantee complete switching to a single consumer.

[0028] In a second aspect, the present disclosure provides a hydraulic system with a changeover valve adapter block combination in a common housing, comprising:

[0029] Connection channels for fluid connection between the consumer working ports of the hydrostatic machine and the changeover valve adapter block combination, and at least one fastening device designed to allow the changeover valve adapter block combination to be mounted gap-free on the consumer working ports of the hydrostatic machine.

[0030] The combination of adapter and changeover valve eliminates the need for additional loose components and enables complete solutions for the respective hydrostatic machines.

[0031] Following the implementation of the device of the first or second aspect, the device can be designed such that the sealing means comprise at least one of sealing rings, cutting edges, USIT rings, soft metal and liquid sealant.

[0032] Advantageous sealants prevent leaks and increase operational safety.

[0033] After implementing the device of the first or second aspect, the device can be designed such that grooves for sealing rings are provided on the adapter block side or on the hydraulic pump side. Grooves enable easier and more secure installation of sealing rings.

[0034] After implementation of the device of the first or second aspect, the device can be designed such that bore channels are closed with screwed, welded or pressed-in blind plugs.

[0035] To ensure safe operation, unused connections are properly sealed.

[0036] Following the implementation of the device of the first or second aspect, the device can be designed such that the fastening device has at least one of flanges, hollow screws, studs or clamps.

[0037] The fastening system is advantageously ensured by secure and, if necessary, reversible fasteners that have the widest possible range of applications.

[0038] After implementation of the device of the first or second aspect, the device can be designed such that the adapter block or the hydraulic system extends over several hydrostatic machines.

[0039] It is also possible to combine several hydrostatic machines, resulting in a more flexible setup.

[0040] Following the implementation of the device of the first or second aspect, the device can be designed such that a switching valve adapter block hydrostatic machine combination is provided in a common housing.

[0041] The adapter block also allows the entire hydraulic system to be combined in a single housing, as with the combination of hydrostatic machine and changeover valve, with the advantage of eliminating further loose parts.

[0042] After implementation of the device of the first or second aspect, the device can be designed such that the switching valve is designed as a slide valve, a poppet valve or as a ball valve.

[0043] Slide valves, poppet valves and ball valves are particularly reliable as advantageous embodiments. The present disclosure provides, in a third aspect, a shredder comprising a hydraulic system according to the first or second aspect.

[0044] The hydraulic system ensures, in particular, the safe and reliable operation of large machines with more than one consumer, also by increasing maintainability.

[0045] Following the implementation of the device of the third aspect, the device can be designed to be a mobile shredder, with the consumers having at least one drive for shredding shafts and one drive for tracked drives.

[0046] In particular, this increase in safety is especially advantageous for mobile shredders, as these have both a drive for shredding shafts and a propulsion drive, which should not be operated simultaneously and whose safe and unambiguous switching must be ensured.

[0047] Drawings

[0048] The invention will now be explained in detail by way of example with reference to the provided drawings, the graphic representations of which individually denote the following:

[0049] Fig. 1: Illustration of a hydraulic system with adapter block between hydrostatic machine (bottom) and changeover valve (top)

[0050] Fig. 2: Cross-section of Fig. 1 showing the connecting channels

[0051] Fig. 3: Isometric sectional view of the adapter block

[0052] Fig. 4: Adapter block from below and in cross-section

[0053] Fig. 5: Hydraulic system with two-part adapter block

[0054] Fig. 6: Hydraulic system with screws as fastening devices and through-holes in the changeover valve. Fig. 7: Hydraulic system with changeover valve adapter block combination.

[0055] Detailed description

[0056] In the description of embodiments of this application, "and / or" describes an associative relationship between connected objects and indicates that three relationships are possible. For example, "A and / or B" can mean the following three cases: only A exists, both A and B exist, and only B exists. In this application, "at least one" means one or more, and "several" means two or more. Furthermore, it should be understood that in the description of this application, terms such as "first," "second," and "third" are used for distinction and description only. These terms should not be interpreted as indicating relative importance or a particular order.

[0057] The invention relates to a hydraulic system comprising a hydrostatic machine 1 and a changeover valve 2, as well as optionally an adapter block 3. The hydraulic system and parts thereof are shown in Figures 1 to 4. The adapter block 3 serves for the direct mounting of the changeover valve 2 to the consumer working ports 1.1 of the hydrostatic machine 1 with a closed hydraulic circuit.

[0058] Hydrostatic machines are fluid power machines used to convert mechanical energy into hydraulic energy or vice versa. They operate on the positive displacement principle and generate or utilize a volume flow of hydraulic fluid to transmit mechanical power. They comprise two main categories: hydraulic pumps, which absorb mechanical drive power and convert it into a pressurized hydraulic flow, and hydraulic motors, which are set into rotation or linear motion by the applied hydraulic fluid, thus delivering mechanical power.

[0059] Within the scope of this disclosure, axial piston or radial piston units can preferably be used as hydrostatic machines 1. These can be used both as hydraulic pumps and as hydraulic motors. Axial piston units comprise machines in which the pistons are arranged in the axial direction of a drive or output shaft. Radial piston units are positive displacement pumps or motors in which the pistons are arranged radially to the drive shaft. An adapter block 3 can be used if the consumer working ports or mounting points between the switching valve 2 and the hydrostatic machine 1 are not flush or aligned without gaps in terms of orientation and / or angle.

[0060] Figure 1 shows a hydraulic system consisting of a hydrostatic machine 1, an adapter block 3, and a changeover valve 2 mounted thereon. The hydrostatic machine 1 is located at the bottom of the illustration and is connected to the adapter block 3. This adapter block 3 connects the consumer working ports of the hydrostatic machine 1 to the consumer working ports of the changeover valve 2.1. The changeover valve 2 is mounted directly on the adapter block 3, thus keeping the arrangement compact.

[0061] The screw connections between the individual components and the compact design enable gap-free assembly, minimizing energy losses and reducing installation space. The mounting position of adapter block 3 is chosen to ensure optimal accessibility for maintenance and inspection.

[0062] Fig. 2 shows the cross-section of the arrangement from Fig. 1 to illustrate the internal details and functionality of the components. The connecting channels 3.1, 3.2 within the adapter block 3 are clearly visible in the cross-section. These channels run from the consumer working ports of the hydrostatic machine 1.1 to the consumer working ports of the changeover valve 2.1.

[0063] The adapter block 3 is designed so that the internal channels run with minimal pressure loss and the geometry of the consumer working connections is taken into account. The angle 'a', which describes the relative position of the consumer working connections, ensures that the components are mechanically compatible. The sealing elements 6, which are arranged between the flange surfaces of the components, effectively prevent leaks and ensure the operational reliability of the system.

[0064] Figure 3 shows an exemplary adapter block 3 in an isometric sectional view. The bores for the screw connections and the connecting channels 3.1, 3.2, which connect the consumer working ports of the hydrostatic machine 1.1 and the changeover valve 2.1, are visible. The sectional view shows how the connecting channels 3.1, 3.2 are routed through the adapter block 3 to ensure optimal fluid transfer. The contact surfaces for gap-free assembly are also clearly visible. These contact surfaces have sealing grooves 3.2 into which the sealing material 6 is inserted to ensure a reliable seal.

[0065] Fig. 4 shows an exemplary adapter block 33 in a bottom view and in cross-section along line EE. The bottom view illustrates the mounting options via screw connections 4, 5 and the precise arrangement of the ports. The cross-section highlights the internal connection channels 3.1, 3.2 and the sealing grooves 3.2 for the O-rings or other sealing materials 6. Additionally, blanking plugs 7 are visible, which close unused openings and thus prevent leaks or unnecessary pressure losses. The angle α between the consumer working ports of the hydrostatic machine 1.1 and the changeover valve 2.1 is clearly shown, demonstrating the design adaptation of the adapter block 3 to the respective requirements.

[0066] A hydraulic system can be provided as a combination of a switching valve 2 and a hydrostatic machine 1, wherein the switching valve 2 and the hydrostatic machine 1 can be directly or indirectly rigidly connected to each other, forming a closed hydraulic circuit, the hydraulic system supplying two or more consumers, and the hydraulic system being configured to switch between the two or more consumers. A rigid connection is here understood to mean a fixed connection, in particular without high-pressure lines with large bending radii.

[0067] The connection can be made by means of a common block or any fastening devices, in particular flanges (e.g., standardized flanges according to ISO 6164 / SAE 518, DIN 3901 / 3902, square flange ISO 6164) for high-pressure applications. These connection options, in particular, are considered here to be direct connections.

[0068] Switching between consumers is optional, but preferably only occurs when the consumers are at a standstill. A complete switchover is preferably protected by a switching position monitoring system.

[0069] The switching position monitoring can be implemented, in particular, by means of inductive or other position sensors, in order to facilitate operation in machines with special safety requirements, especially shredders. The hydraulic system optionally includes an adapter block 3 between the hydrostatic machine 1 and the changeover valve 2. This connection option is considered an indirect connection in this document. This adapter block 3 is specifically designed with the following features.

[0070] As can be seen in Fig. 2, Fig. 3 and Fig. 4, the connecting channels or bores 3.1, 3.2 run within the adapter block 3 and enable the direct fluid connection between the consumer working ports 1.1 of the hydrostatic machine 1 and the consumer working ports 2.1 of the changeover valve 2. The channels are designed to correspond to the flange geometries of the consumer working ports and to rest without gaps, thereby minimizing pressure losses.

[0071] Figures 3 and 4 show the construction of the adapter block 3 in sectional view. The consumer working connections of the hydrostatic machine 1.1 and the switching valves 2.1 are designed as flanges (e.g., standardized flanges according to ISO 6164 / SAE 518, DIN 3901 / 3902, square flange ISO 6164) for the high-pressure area, the surfaces of which, depending on the manufacturer / type, may be on the same plane or at an angle α to each other (e.g., less than 90° in Figure 3).

[0072] The flanges shown in the illustration, but not necessarily otherwise, each have four threaded holes, which here serve to fasten the adapter block 3 using screws 4 and 5. The contact surfaces of the adapter block 3.1 and 3.2 are designed so that they match the flange surfaces of the consumer working connections of the hydrostatic machine 1.1 and the changeover valve 2.1 in alignment and angle and rest against them without gaps.

[0073] Holes not required for the fluid or the fastening are, as mentioned, screwed or pressed shut with blind plugs 7 or optionally also serve to accommodate sensor, valve or other connections (e.g. hydraulic lines).

[0074] The adapter block 3 has at least one fastening device, for example in the form of the aforementioned screws 4, 5, which pass directly through the changeover valve 2 or the adapter block 3, each of which may have threaded holes and / or through-holes. Optionally, a variety of other fastening mechanisms, not exhaustively listed here, such as 4-hole flanges, banjo bolts, studs, or clamps, can also be used. As shown in Fig. 4, these screws 4, 5 engage in the threaded holes of the hydrostatic machine 1 or the adapter block 3 to ensure a secure and gap-free connection.

[0075] Sealing elements 6, such as O-rings or USIT rings, are arranged between the flange surfaces of the hydrostatic machine 1.1 and the changeover valve 2.1, as well as the corresponding contact surfaces of the adapter block 3, to ensure a reliable seal of the hydraulic connections. The corresponding grooves for the sealing elements 6 are optionally integrated into the contact surfaces of the adapter block 3, but can also be located on the side of the hydrostatic machine 1 or the changeover valve 2.

[0076] As shown in Fig. 5, the adapter block 3 optionally consists of two separate parts: a first / lower adapter block 3.4, which is mounted on the consumer working ports of the hydrostatic machine 1, and a second / upper adapter block 3.3, which is connected to the consumer working ports of the changeover valve 2. These two parts each have flanges that allow a gap-free connection between the two adapter block components. The two adapter blocks 3.3 and 3.4 can then be connected to each other using bolts.

[0077] The advantage of this design lies in the flexibility of the assembly as well as the possibility of taking into account different flange geometries of the hydrostatic machine 1 and the switching valve 2.

[0078] The changeover valve 2 can be configured in various ways depending on the application requirements, including, but not limited to, a 6 / 2-way changeover valve, two 3 / 2-way changeover valves, one 6 / 3-way changeover valve, an 8 / 3-way changeover valve, or two 4 / 3-way changeover valves. These configurations allow switching between multiple consumers within a closed hydraulic circuit and increase system flexibility. Switching is achieved mechanically, hydraulically, or electrically.

[0079] The 6 / 2-way switching valve is a type of valve with six ports and two switching positions. It is typically used to switch the hydraulic oil flow between two consumers that do not need to operate simultaneously. In a closed hydraulic circuit, this valve performs the following functions: The 6 / 2-way valve directs the high-pressure flow from the hydrostatic machine 1 either to a first consumer (e.g., drive motors of a shredding shaft) or to a second consumer (e.g., travel motors of a tracked undercarriage). Simultaneously, the return flow from the respective consumer is fed back into the circuit. In the 6 / 3-way switching valve configuration, an additional neutral position is maintained when the valve is not actuated.

[0080] Two 3 / 2-way valves can be used as an alternative to a single 6 / 2-way valve. Each 3 / 2-way valve has three ports and two switching positions.

[0081] The 8 / 3-way diverter valve is a valve type with eight ports and three switching positions. It is used when more than two consumers need to be operated in a closed hydraulic circuit. Unlike the 6 / 2-way valve, the 8 / 3-way valve allows switching between multiple consumers by selectively directing the oil flow to one of three possible consumers. Each consumer can be supplied with pressurized and return flow in the closed circuit. The 8 / 3-way valve enables the operation of up to three consumers with just one valve.

[0082] Two 4 / 3-way valves can be used as an alternative to a single 8 / 3-way valve. Each 4 / 3-way valve has four ports and three switching positions.

[0083] The diverter valves can act as hydraulic separators, redirecting the fluid flow from the consumer ports to the respective consumer. In their basic configuration, the diverter valves perform no further control or regulation functions during operation (e.g., in a shredder or ferry operation); switching preferably occurs when the machine is stationary. During operation, all consumer ports of the hydrostatic machine are connected to all consumer ports of the selected consumer.

[0084] Consumer working connections within the meaning of this disclosure are the hydraulic connections of a consumer or a hydrostatic machine through which working fluid, in particular hydraulic oil, is actively supplied or discharged in order to perform mechanical work. They include all pressure-bearing fluid channels or...

[0085] Pipes that are necessary for the intended operation of the consumer or the hydrostatic machine, and may also include additional control or leakage oil connections depending on the design.

[0086] Optionally, a switching position monitoring system using inductive or other position sensors can detect the switching position of the valve to prevent uncontrolled machine movements and / or damage to the hydraulic components.

[0087] In addition to the pure switching function, the hydraulic system can also be expanded with pressure relief valves to protect consumers and / or pressure equalization connections that prevent leakage-related pressure build-up (and thus unwanted movement of the consumers) between the inactive consumer working connections.

[0088] The connection between adapter block 3, hydrostatic machine 1 and changeover valve 2 can be made in various ways:

[0089] Fig. 6 shows optional fastening devices with screws 4, 5 in through holes in the changeover valve 2 and threaded holes in the adapter block 3, as well as screws in through holes in the adapter block 3 and threaded holes in the hydrostatic machine 1.

[0090] Optionally, either the switching valve 2 or the adapter block 3 has through holes and the other component has corresponding threaded holes to allow screwing to the adapter block 3 from the direction of the switching valve 2.

[0091] Alternatively, the switching valve 2 and the adapter block 3 have through-holes arranged so that the fastening screws through the switching valve 2 and the adapter block 3 engage directly into threaded holes of the hydrostatic machine 1.1; likewise, a connection from the hydrostatic machine 1 via through-holes into threaded holes of the switching valve 2 is possible.

[0092] With reference to Fig. 7, a hydraulic system disclosed herein is described, comprising a combination of the adapter block 3 and the changeover valve 2. This eliminates the need for separate mounting of the changeover valve 2 onto the adapter block 3. The connection can be reversible using the described fastening devices or irreversible as a single block.

[0093] Fig. 7 shows a hydraulic system with a changeover valve-adapter block combination, in which the adapter block 3 and the changeover valve 2 are integrated and combined in a common housing. As with the adapter block 3 as a single block, connection channels are provided for fluid connection between the consumer working ports of the hydrostatic machine 1.1 and the changeover valve-adapter block combination. At least one mounting device is provided, designed so that the changeover valve-adapter block combination can be mounted without gaps to the consumer working ports of the hydrostatic machine 1.1. The connection channels 3.1, 3.2 are integrated directly into the housing. This design reduces the number of mounting interfaces and offers additional advantages in terms of installation space and sealing.

[0094] The switching valve 2 can be in various versions according to the requirements of the application as described above, in particular as a 6 / 2-way switching valve, two 3 / 2-way switching valves, or an 8 / 3-way or two 4 / 3-way switching valve.

[0095] Here too, the switching valve 2 can be fastened from the direction of the hydrostatic machine 1, as well as from the switching valve 2 itself, wherein, for example, the switching valve adapter block combination has through-holes arranged so that the fastening screws through the switching valve adapter block combination engage directly into threaded holes of the hydrostatic machine 1.1, or the hydrostatic machine 1 has through-holes arranged so that the fastening screws through the hydrostatic machine 1 engage directly into threaded holes of the switching valve adapter block combination.

[0096] With regard to both the hydraulic system in general and the hydraulic system containing the changeover valve adapter block combination, the sealing material 6 can comprise at least one of the following: sealing rings, cutting edges, USIT rings, soft metal, and liquid sealant. The seal can be applied in both axial and radial directions, e.g., as short sleeves with radial sealing rings connecting the hydrostatic machine 1 and the changeover valve 2.

[0097] Grooves for sealing rings can be provided on the adapter block side or on the hydraulic pump side.

[0098] Bore channels can be closed with blanking plugs 7. These blanking plugs 7 can be screwed, pressed, or welded in place to seal unused bores or to allow for future sensor, valve, or other connections (e.g., hydraulic lines). The fastening device can optionally include at least one of four-hole flanges, banjo bolts, studs, clamps, or other fastening mechanisms to securely and gap-free connect the adapter block 3 to the hydrostatic machine 1 and the changeover valve 2.

[0099] The adapter block 3 or the entire hydraulic system can extend over several hydrostatic machines 1 and supply, for example, several switching valves 2 and consumers.

[0100] The changeover valve 2 can be designed as a slide valve, a poppet valve or in rotary valve design to meet the specific requirements of the application.

[0101] In a poppet valve, the ports are connected or disconnected by placing or removing a sealing element. It is characterized by high tightness and a robust design. This valve is particularly suitable for applications with high pressures and flow rates, such as those found in closed hydraulic circuits.

[0102] In a gate valve, the gate is the movable element of the valve, which is moved along an axis by an actuating force (e.g., hydraulic, mechanical, or electrical). The movement of the gate opens or closes flow paths.

[0103] The rotary valve differs from the spool and / or poppet valve in that it uses a rotating spool (rotating body) instead of a linearly moving spool. This valve is characterized by a very compact design and insensitivity to dirt. Preferably, the hydraulic systems described here can be rotary valves with ball valves, also referred to here as ball valves.

[0104] Implementing the hydraulic system as a switching valve-adapter block-hydrostatic machine combination in a common housing reduces the number of components and offers compactness and efficiency.

[0105] Each of the hydraulic systems described above can be used explicitly in mobile or stationary shredders, as well as in construction machinery, material handling equipment, forestry vehicles, and special-purpose vehicles. For example, in the case of mobile shredders, the hydraulic system can be designed to allow the use of a single hydrostatic machine for various consumers, such as driving shredding shafts and simultaneously driving track drives, or generally for propulsion. In forestry machines and cranes, a single hydrostatic machine can be used for both travel propulsion and winch drive as switchable consumers. These different uses can be considered distinct operating modes.

[0106] Shredders are primarily small-scale shredding machines used to break down various materials such as concrete, reinforced concrete, plastic, wood, metal, paper, or mixed waste. They typically feature a cutting chamber equipped with rotating cutting tools like knives, hammers, or cutting shafts, a drive system, and inlet and outlet devices for material feeding and discharge. The cutting tools, made of materials such as hardened steel or other wear-resistant materials, can reduce the material to the desired size by cutting, tearing, shearing, pressing, striking, or grinding. These machines can be designed to support different operating modes, such as shredding hard or soft materials, and are suitable for both stationary and mobile applications.

Claims

Claims 1. A hydraulic system with a closed hydraulic circuit, comprising a switching valve (2) and a hydrostatic machine (1) directly or indirectly rigidly connected thereto, wherein the hydraulic system supplies two or more consumers and wherein the hydraulic system is configured to switch between the two or more consumers.

2. The hydraulic system according to claim 1, wherein the switching of all consumer working connections between individual consumers only takes place when the consumers are at a standstill and wherein a complete switching is secured by a switching position monitoring.

3. A hydraulic system according to claim 1 or 2, wherein the hydraulic system has an adapter block (3) between the hydrostatic machine (1) and the switching valve, and wherein the adapter block (3) comprises: Connection channels for fluid connection between the consumer working ports of the hydrostatic machine and the changeover valve (1.1, 2.1), at least one fastening device designed so that the adapter block (3) can be mounted without gaps on the consumer working ports of the hydrostatic machine and the changeover valve (1.1, 2.1), Sealing means (6) which are arranged between the flange faces of the adapter block (3.1, 3.2) and the consumer working ports of the hydrostatic machine and the changeover valve (1.1, 2.1) to seal the hydraulic connections.

4. The hydraulic system according to claim 3, wherein the adapter block (3) comprises a first adapter block (3.4) and a second adapter block (3.3), wherein the first adapter block (3.4) can be mounted gap-free on the respective consumer working ports of the hydrostatic machine (1) and the second adapter block (3.3) can be mounted gap-free on the respective consumer working ports of the hydrostatic machine and the switching valve (1.1, 2.1), and wherein the first and second adapter ports have connections at which the first and second adapter ports can be connected to each other without gaps.

5. The hydraulic system according to any one of claims 3 to 4, wherein the changeover valve (2) is a 6 / 2-way changeover valve, a 6 / 3-way changeover valve, two 3 / 2-way changeover valves, two 4 / 3-way changeover valves, or an 8 / 3-way changeover valve.

6. A hydraulic system with a changeover valve adapter block combination in a common housing, comprising: Connection channels for fluid connection between the consumer working ports of the hydrostatic machine (1.1) and the changeover valve adapter block combination, and at least one fastening device designed so that the changeover valve adapter block combination can be mounted without gaps on the consumer working ports of the hydrostatic machine (1.1).

7. The hydraulic system according to any one of claims 3 to 6, wherein the sealing means (6) comprise at least one of sealing rings, cutting edges, USIT rings, soft metal and liquid sealant.

8. The hydraulic system according to claim 7, wherein grooves for sealing rings are provided on the adapter block side or on the hydraulic pump side.

9. The hydraulic system according to any one of claims 3 to 8, wherein bore channels are closed with screwed, welded or pressed-in blind plugs (7).

10. The hydraulic system according to any one of claims 3 to 9, wherein the fastening device comprises at least one of flanges, hollow screws, studs or clamps.

11. The hydraulic system according to any one of claims 3 to 10, wherein the adapter block (3) or the hydraulic system extends over several hydrostatic machines (1).

12. The hydraulic system according to any one of claims 3 to 11, wherein a switching valve adapter block hydrostatic machine combination is provided in a common housing.

13. The hydraulic system according to any one of claims 1 to 12, wherein the switching valve (2) is designed as a spool valve, a poppet valve or as a ball valve.

14. A shredder comprising a hydraulic system according to any one of claims 1 to 13.19 15. The shredder according to claim 14, wherein it is a mobile shredder and wherein the consumers have at least one drive of shredding shafts and one drive of tracked drives.

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