Valve block for a work machine

Abstract

The invention relates to a valve block for a machine for the controlled application of pressure to the brake system of a trailer connected to the machine. The valve block includes a pneumatically controlled relay valve (10) configured to control the application of pressure to the trailer's brake system. The valve block also includes an electrically controlled pneumatic valve assembly (20) configured to control the relay valve (10). Furthermore, the valve block includes a hydraulically controlled redundancy valve assembly (30), a first and a second pneumatic connection (70, 72), a main electrical connection (76), a hydraulic connection (81), and a housing (90) with one housing side. The relay valve (10), the pneumatic valve assembly (20), and the redundancy valve assembly (30) are arranged within the housing (90).The first and second pneumatic connections (70, 72) are arranged on the housing side of the housing (90). Furthermore, the invention relates to a machine with such a valve block.

Description

Technical area

[0001] The present invention relates to a valve block for a work machine for the controlled pressurization of a braking system of a trailer connected to the work machine. The invention also relates to a work machine. State of the art

[0002] Trailer braking systems are often operated with pneumatic pressure from a working machine and controlled by valves in the working machine. EP 3 683 109 B1 describes a valve arrangement of a hydraulically braked towing vehicle for controlling the brake pressure of a pneumatically braked trailer. Installing the valves for controlling the braking system of a working machine is often very complex and requires a lot of space. Connecting all the valves, for example, when redundancy and a parking brake function are also provided, can be difficult. Description of the invention

[0003] A first aspect relates to a valve block for a work machine for the controlled pressurization of a braking system of a trailer connected to the work machine. The braking system can be designed to decelerate the trailer while driving. The braking system can be designed to hold the trailer stationary. The braking system can be designed to provide further braking functions. The work machine can be designed, for example, as an agricultural machine or construction machine. An example of an agricultural machine is a tractor. The work machine can be designed as a tractor that can pull the trailer connected to it. The work machine can, for example, have a drive motor. The braking system can be designed to provide braking force by pressure. The pressure can, for example, be used to actuate respective brakes. The pressure can, for example, be provided pneumatically.

[0004] A valve block can be a component comprising one or more valves designed to control the braking system using pneumatic or hydraulic pressure. The valve block can have a housing, which can be formed, for example, from several interconnected parts. The valve block can be arranged on the work machine. However, the valve block can also be arranged on the trailer.

[0005] The valve block has a pneumatically controlled relay valve which is designed to control the pressure of the trailer's braking system. A relay valve can be a valve which transmits or does not transmit a pressure depending on a control signal. Such a control signal can be, for example, a pressure signal or an electrical signal. The relay valve can be pneumatically controlled, for example. The relay valve can be designed, for example, to transmit a pressure when a control pressure is applied to the relay valve. The relay valve can also be designed not to transmit a pressure when pressure is applied. The relay valve can have one or more control inputs for this purpose. For example, the relay valve can transmit a pressure when pressure is applied to one control input or when no pressure is applied to another control input.By controlling the pressure of the brake system, a braking function of the brake system can be controlled. For example, braking can be triggered when pressure is transmitted to the brake system. The relay valve can be designed as a proportional valve. For example, an input pressure can be freely reduced relative to an output pressure. The relay valve can, for example, transmit a portion of the pressure provided by a pressure source to the trailer's brake system.

[0006] The valve block has an electrically controlled pneumatic valve device, wherein the pneumatic valve device is designed to control the relay valve. The pneumatic valve device can have one or more valves that are electrically controllable. The valves can be designed to be adjustable depending on an electrical control signal, for example, between an open position and a closed position. The valves can have a basic position to which the valves automatically return if the control signal fails. For this purpose, the valves can have a spring, for example. The valves of the pneumatic valve device can be electrically controllable to adjust the relay valve and, optionally, any other components connected to it. The valves of the pneumatic valve device can, for example, be accommodated together in the housing of the valve block.The pneumatic valve device can control the relay valve using a pneumatic pressure signal. For example, a different control pressure can be supplied to the relay valve depending on the electrically controlled position of the valves of the pneumatic valve device. The pneumatic valve device can be connected to the same or a different pressure source than the relay valve. The pneumatic valve device can, for example, have three electronically controlled valves. The pneumatic valve device can have 3 / 2-way valves. It can also additionally or alternatively have 2 / 2-way valves. The pneumatic valve device can also have automatically switching valves.

[0007] The valve block has a hydraulically controlled redundancy valve device designed to control the pressure of the trailer's braking system in the event of a control failure by the pneumatic valve device. For example, the pneumatic valve device may fail if a control device, such as a vehicle ECU, experiences a short circuit. The trailer's braking system may thus be both electrically and hydraulically controllable. For example, the valve block is designed so that the hydraulic control is only activated in the event of a control failure by the pneumatic valve device. The redundancy valve device may be a valve device designed to provide redundant control. The redundancy valve device may have one or more hydraulically controllable valves.The valves can be designed to be adjustable depending on a hydraulic control pressure, for example between an open position and a closed position. The valves can have a basic position to which the valves automatically return in the event of a failure of the hydraulic control pressure. The valves can have a spring for this purpose, for example. The valves of the redundancy valve device can be hydraulically controlled to adjust the relay valve and, optionally, any other components connected to it. The valves of the redundancy valve device can, for example, be accommodated together in the housing of the valve block. The redundancy valve device can control the relay valve using a pneumatic pressure signal. For example, a different control pressure can be passed to the relay valve depending on the electrically controlled position of one of the valves of the redundancy valve device.In addition, the redundancy valve device can also have pneumatically controlled and alternatively or additionally automatically switching valves. The valves of the redundancy valve device can, for example, be accommodated together in a housing. The redundancy valve device can, for example, convert a hydraulic control signal into a pneumatic control signal. For this purpose, the redundancy valve device can use a relay valve that is controlled via hydraulic pressure and can also be referred to as a redundancy relay valve. For example, a hydraulic control pressure can adjust the relay valve to adjust the forwarding of a pneumatic pressure. The relay valve can also block the forwarding of a pneumatic pressure. The redundancy valve device can be designed to draw pressure from the same pressure source as the pneumatic valve device and make it available to the braking system.Alternatively or additionally, it can also be designed to draw pressure from another pressure source.

[0008] The redundancy relay valve can have a valve piston, a valve seat, a valve spring, and a valve cylinder. The valve piston can have a central bore. The central bore of the valve piston can serve to save weight and avoid air pockets. The valve cylinder can have a central bore through which, for example, air can flow in at least one position of the redundancy relay valve. The valve seat can surround a tip of the valve piston. The valve seat can be designed as a separate part from the housing. The valve spring, for example, can rest against the valve seat. The valve spring can be designed to press the valve piston into an open position. In a further state, the valve piston can be pressed against the valve cylinder, wherein both the valve piston and the valve cylinder are axially displaced for the state change.The valve seat can have an adapted geometry to enable the largest possible air flow through the redundancy valve. In one position of the redundancy valve, the diameter of a clearance around the valve piston can be nearly constant, for example, because the valve seat has a radially outward-facing bulge in the area of ​​an adjacent end of the valve piston.

[0009] The valve block has a first pneumatic connection configured to connect the relay valve to a pressure source of the work machine. The relay valve can be connected to the first pneumatic connection via a pneumatic line extending at least partially inside the valve block. The first pneumatic connection can, in turn, be connected to a pressure source of the work machine. This connection can be provided via a pneumatic pressure line. The first pneumatic connection can form a pressure input for the valve block.

[0010] A pneumatic connection can, for example, be designed for connecting a pneumatic line, such as an air hose, to the valve block. A pneumatic connection can, for example, have a standard coupling. A pneumatic connection can form an opening in the valve block, for example a substantially round opening in the housing of the valve block. For example, a pneumatic connection can allow a connection to a pneumatic pressure hose. The pressure source of the work machine can have a pressure reservoir. For example, such a pressure reservoir can be provided by a tank or an accumulator. Alternatively or additionally, the pressure shaft of the work machine can also have a pressure generating device, such as a compressor. A hydraulic connection can be designed to transmit a gas, such as compressed air.

[0011] The valve block has a second pneumatic connection which is designed to connect the valve block to the trailer's braking system. The second pneumatic connection can have the same or largely the same properties as the first pneumatic connection. For example, both or all pneumatic connections can be designed identically. For example, the two pneumatic connections can be provided by identical components. The second pneumatic connection can be designed to connect the valve block to the braking system via a pneumatic pressure line. The valve block can thus control the braking system. The braking system can be connected via the second pneumatic connection for controlled pressurization. For example, the second pneumatic connection can transmit pressure to the trailer for actuating the brakes of the trailer's braking system.Alternatively or additionally, the valve block can thus pressurize the brake system. The second pneumatic connection can form a pressure output for the valve block. The second pneumatic connection can, for example, be connected to a pressure output of the relay valve and also of the redundancy relay valve.

[0012] The valve block has a first main electrical connection, which is designed to connect the pneumatic valve device to a control device of the work machine. The main electrical connection can be a connection provided via a plug, a contact, or a similar mechanism. The main electrical connection can be designed, for example, as a male or female connection. The electrical connection can be designed for connecting one or more electrical lines and can have, for example, a corresponding number of pins for this purpose. The main electrical connection can transmit data, electrical current, and alternatively or additionally, electrical control signals. The main electrical connection can be designed, for example, to transmit electrical control signals to the electrically controllable valves of the pneumatic valve device.The main electrical connection can be configured, for example, to transmit sensor data, such as pressure sensor data. The main electrical connection can be configured to connect sensors to the control device. The sensors thus connected can include one or more pressure sensors. The main electrical connection can be, for example, substantially square, rectangular, or round. The main electrical connection can be configured as a standardized connection.

[0013] The valve block has a hydraulic connection designed to connect the redundancy valve device to a hydraulic control circuit of the work machine. The hydraulic control circuit can, for example, be a hydraulic working circuit or a dedicated hydraulic circuit for controlling the trailer's brakes. A hydraulic control pressure in the hydraulic control circuit can, for example, be adjusted by an operating device such as a brake pedal or a pump. This allows the braking system of the valve block to continue to be hydraulically controlled, for example, in the event of a failure of the electrical control. The hydraulic control circuit of the work machine can also be designed to provide additional functions of the work machine. For example, it can be designed to actuate hydraulic cylinders, brakes, cranes, or other elements of the work machine.The hydraulic control circuit of the work machine can also be designed to control other elements of the trailer of the work machine and to supply them with hydraulic pressure additionally or alternatively.

[0014] A hydraulic connection can be configured, for example, for connecting a hydraulic line, such as a hydraulic hose, to the valve block. A hydraulic connection can, for example, comprise a standard coupling. A hydraulic connection can form an opening in the valve block, for example, a substantially round opening in the housing of the valve block. For example, a hydraulic connection can allow a connection to a hydraulic pressure hose. A hydraulic connection can be configured to transmit a fluid, such as a hydraulic fluid.

[0015] A longitudinal axis of the hydraulic connection can be offset, i.e. parallel but not coaxial, to a connection for a hydraulic pressure sensor of the valve block. This allows the valve block to be very compact. The hydraulic connection can transmit hydraulic pressure alternatively or additionally. The hydraulic connection can have a smaller diameter than the pneumatic connections. The hydraulic connection can also have a diameter the same or larger than the pneumatic connections. The hydraulic control circuit of the work machine can be designed to control the redundancy valve device and additionally or alternatively supply it with hydraulic pressure. The hydraulic pressure for controlling the redundancy valve device can be provided by a hydraulic fluid flowing through one or more valves of the redundancy valve device.

[0016] The valve block has a housing with a housing side, wherein the relay valve, the pneumatic valve device, and the redundancy valve device are arranged in the housing. The housing side can be a front side of the housing. Further valves and valve devices of the valve block can be arranged in the housing, for example all valves and valve devices described here. The valve block can be free of valves and valve devices other than those described here. The housing can be an assembly that encloses an interior of the valve block. The housing can be formed from a single component or from multiple components. A seal can be arranged between interconnected components. The housing can have an approximately cuboid shape. The housing can also have an irregular shape.The housing can have a shape that essentially corresponds to the shape of the components located inside or at least corresponds in some areas. The housing can form valve seats for some valves. The housing can form connecting lines between valves, valve devices and alternatively or additionally connections. The housing side of the housing can be one side of a substantially cuboid-shaped housing. The housing side can have several interconnected or separate surfaces that point essentially in one direction. The direction in which a surface points can be defined, for example, by its normal pointing away from the housing. Alternatively or additionally, the housing side can be a side that, when the valve block is installed, extends in the vertical direction of the vehicle and alternatively or additionally points to a side of the work machine.For example, the housing side can face away from the trailer. The installed state of the valve block can be a state in which the valve block is attached to the work machine. The installed state can also be a state in which the valve block is connected to pressure lines and, alternatively or additionally, electrical lines of the work machine and, alternatively or additionally, the trailer.

[0017] The first pneumatic port and the second pneumatic port are arranged on the housing side of the housing. The pneumatic ports can have an orientation which is defined, for example, via a centerline through an opening of the pneumatic ports. This longitudinal direction can be arranged substantially normal to the housing side, i.e. orthogonal to the housing side and protruding from the housing side. Ports arranged on the housing side of the housing can form an integral part of the housing side of the housing. Alternatively or additionally, they can also comprise components which are fastened to the housing side of the housing. The ports arranged on the housing side can have a through-opening in the housing which is aligned parallel to the housing side of the housing.For example, an electrical connection may have an insertion opening that points in a different direction, for example because the electrical connection has an angled plug.

[0018] The described arrangement makes it possible to provide a particularly compact valve block. This saves installation space and makes installation, repair, maintenance, and cleaning of the valve block particularly easy. For example, the braking system can be easily connected to the brake block when coupling the trailer. The described integrated arrangement of the valves in a valve block makes the system as a whole simpler, lighter, and additionally or alternatively more compact. Furthermore, the described arrangement makes it possible to provide a valve block that is particularly ergonomic, simple, and additionally or alternatively efficient to install. For example, the valve block can be mounted directly on the trailer. Alternatively or additionally, the valve block can also be mounted from just one side using the features described.For example, the valves can be inserted into the housing from a side that is opposite the housing side. For example, all valve components can be inserted from the rear of the housing if the housing side is the front. With a one-sided assembly, the valve block does not need to be rotated during assembly.

[0019] According to one embodiment of the invention, pneumatic connections between the components of the valve block are formed by the housing. Pneumatic connections can be connections that transmit pneumatic pressure and, alternatively or additionally, a pneumatic fluid, such as air. Pneumatic connections can additionally be connected to valves. The pneumatic connections between the components of the valve block can thus be provided essentially by a single component. This component can be a cast component or a milled part. The component can have a labyrinth shape, and the connections can form an integral part of the housing. Alternatively or additionally, the housing can also have seals for the corresponding connections. For example, the housing can form connecting lines between respective pneumatic ports and respective valve devices or valves.The housing can also form connecting lines between different valves and valve devices. Alternatively or additionally, the housing can also form hydraulic connections, such as a hydraulic connecting line between the redundant valve device and the hydraulic connection. This eliminates the need for separate connecting lines.

[0020] For example, such pneumatic connections can be used to connect the pneumatic valve device to the relay valve to provide a braking function. Furthermore, such pneumatic connections can connect the relay valve to a parking brake valve device to provide a parking brake function. This is described in detail below. The corresponding pneumatic connections can also be connected to sensors and, additionally or alternatively, to a vent. By forming the connection through the housing, an integral function is achieved. This allows for a particularly lightweight and, additionally or alternatively, particularly compact valve block to be provided. The number of parts can also be kept very low.

[0021] According to one embodiment of the invention, the main electrical connection is arranged on the housing side of the housing. The main electrical connection can form an integral part of the housing side of the housing. Alternatively or additionally, it can also comprise components that are arranged on the housing side of the housing. The main electrical connection can be in the same plane as other connections on the housing side of the housing. However, the main electrical connection can also be offset to the front or rear relative to other connections. The main electrical connection can, for example, be arranged on a different housing part than the pneumatic connections on the housing side.

[0022] By locating the main electrical connection on the side of the housing, a particularly easily accessible main plug is provided. This can be particularly advantageous during assembly, cleaning, and additional or alternative maintenance. As already described above, this also enables assembly and fastening from only one side. Furthermore, the main plug can be easily accessible, for example, because its accessibility is not obstructed by other connecting lines, such as hydraulic lines.

[0023] According to one embodiment of the invention, the valve block has a third pneumatic connection, which is designed to connect the relay valve to a pressure source of the trailer. The third pneumatic connection can be arranged on the housing side of the housing. The third pneumatic connection can, for example, be designed like the first and second pneumatic connections. This makes it possible to provide a redundant pressure supply if the trailer also has a pressure source. In addition, the operation of the braking system can be supported by the pressure source. The valve block can, for example, have only the first pneumatic connection, only the third pneumatic connection, or both the first and third pneumatic connections.The trailer's pressure source can provide a more even pressure supply to the valve block than with just one pressure source, which can reduce or completely prevent pressure drops in the working machine and, alternatively or additionally, the trailer when the braking system is actuated.

[0024] The first pneumatic connection and the second pneumatic connection can be connected to each other in the valve block, for example via a valve. The valve can be designed as a throttle valve that connects the first and third pneumatic connections. The throttle valve can connect the pressure source of the work machine and the pressure source of the trailer. The throttle valve can inhibit or even separate a connection between the two in the event of a rapid pressure drop in the pressure source of the trailer or the work machine. Such a rapid pressure drop can be caused, for example, by a leak or a rupture of a pneumatic pressure connection. This provides redundancy in the pressure supply to ensure safe braking even in the event of a rapid pressure drop.In addition, the throttle valve can also be designed to prevent unintentional activation and, alternatively or additionally, deactivation of a parking brake function in the event of a pressure drop, for example, at one of the two pressure sources. The throttle valve can be controlled, for example, by the pneumatic valve device.

[0025] According to one embodiment of the invention, the valve block comprises a parking brake valve device configured to control a parking brake function in the trailer's braking system. The parking brake valve device may be a device comprising valves, for example, the parking brake valve device described above. The valves may, for example, be electrically controllable. The parking brake valve device may be controlled by the control device described above. The parking brake function may prevent the trailer from rolling away when it is parked. The parking brake function may additionally or alternatively prevent the work machine from rolling away when it is parked.

[0026] The parking brake valve device can have an electrically controlled first parking brake valve and an electrically controlled second parking brake valve. However, the parking brake valve device can also have a single parking brake valve. If the parking brake valve device has multiple parking brake valves, these can be designed identically or essentially identically. With multiple parking brake valves, redundancy can be provided, for example to prevent undesired activation of the parking brake in the event of a failure of one of the parking brake valves. The parking brake valves can be designed to be electrically controlled and, for example, connectable to the control device of the work machine for control purposes. By adjusting the parking brake valves, the relay valve can be controlled, for example, to actuate the braking system.The parking brake valves can also be connected directly to the trailer brakes, for example if they have a separate control circuit for the parking brake function.

[0027] A parking brake valve can have a venting device, which, for example, forms an output of a parking brake valve. The parking brake valves can, for example, have an inlet connected to the first pneumatic connection and, alternatively or additionally, to the third pneumatic connection, i.e., to respective pressure sources. The parking brake valves can have a first output connected to the relay valve. The parking brake valves can have a second output connected to venting to the environment via the venting device. For example, the parking brake valves are designed as electrically controlled 3 / 2-way valves. For example, such a venting device can be arranged on an outer side of the valve block, such as the housing side. The venting device can be operated manually and, alternatively or additionally, automatically.The parking brake valve's venting device can be protected from environmental influences. This can be achieved, for example, by a valve protection cap and, additionally or alternatively, a rubber washer. The valve protection cap can be mounted on the housing in such a way that it covers the parking brake valve's venting device and thus shields it from influences such as a water jet. The valve protection cap can be attached via valve screws to one side of the housing and, alternatively or additionally, to the associated parking brake valve and, alternatively or additionally, to a connection for controlling the parking brake valve. The valve block can have an associated venting device for each parking brake valve.

[0028] The rubber disc can serve as a seal for the venting device. For example, when undeformed, it can prevent water or foreign matter from entering the venting device. The rubber disc can also deform to vent the parking brake valve, allowing air to flow outwards. To increase the flexibility of the rubber disc and thus allow the parking brake valve to be vented with little resistance, the rubber disc can be provided with slots. For example, the rubber disc can be provided with four slots. These slots can be evenly distributed along a circumferential direction of the valve. These slots can be directed radially outwards or can be arranged in a different way on the rubber disc.

[0029] According to one embodiment of the invention, the parking brake valve device has an electrical first parking brake connection, which is designed to connect the first parking brake valve to the control device of the work machine. Alternatively or additionally, the parking brake valve device has an electrical second parking brake connection, which is designed to connect the second parking brake valve to the control device of the work machine. A parking brake connection can, for example, transmit data, electrical control signals and, alternatively or additionally, electrical current. A parking brake connection can have an HDSCS connector. A parking brake connection can additionally or alternatively also have other standardized connectors or even non-standardized connectors. Both parking brake connections can be of identical design. The respective parking brake connections can be arranged on the housing side of the housing.

[0030] A longitudinal axis of a connection opening of the parking brake connection can be arranged at right angles to a longitudinal axis of the parking brake valve and / or to a through-opening for the parking brake connection in the housing. For example, the connection opening for a control line can point to the side even though the respective parking brake connection is arranged on the housing side of the housing. A longitudinal axis of the parking brake valve can extend orthogonally through a housing side of the housing. For example, the connection opening of the parking brake connection can be arranged at right angles to the parking brake valve. The connection opening of a parking brake connection can also be aligned parallel to a housing side of the housing. The connection opening of one or both parking brake connections can be aligned substantially towards the main electrical connector.

[0031] According to one embodiment of the invention, the first parking brake connection and the second parking brake connection are arranged on the housing side of the housing. The parking brake valves and, alternatively or additionally, the parking brake connections can be arranged adjacent to one another. In a particularly space-saving arrangement, the parking brake connections can be arranged rotated relative to one another. This can mean that the parking brake valves are arranged next to one another and the orientations of the connection openings of the parking brake connections form an angle to one another. For example, the connection opening of the first parking brake connection can point towards the main electrical connection and, alternatively or additionally, can be aligned orthogonally to a side surface of the valve block. For example, the connection opening of the first parking brake connection can be aligned obliquely to the main electrical connection and an underside of the valve block.This allows for a particularly tight and therefore space-saving arrangement. The two parking brake connections can be aligned essentially in the direction of the main electrical connector. The parking brake connections can also be arranged next to the main electrical connector.

[0032] The described parking brake valve device can provide a parking brake function. This can improve the safety of the work machine or trailer. The described arrangement of the parking brake valves and their parking brake connections enables a particularly compact and simple design and connection to the parking brake valve device.

[0033] According to one embodiment of the invention, the main connector, the first parking brake connector, and the second parking brake connector are arranged to be connected to the control device of the work machine via a common wiring harness. A wiring harness may comprise a bundle of multiple cables. These cables may transmit data, electrical power, and additionally or alternatively control signals. A wiring harness may comprise a common outer protective sheath or connect multiple cables together via connecting means.

[0034] Such connecting means can include, for example, cable ties, wires, or other connecting means. Such a wiring harness can be split into several cable strands shortly before the valve block. This can include a distance of up to 2 cm, up to 5 cm, up to 10 cm, up to 20 cm, or up to 50 cm shortly before the valve block. The parking brake connections and, additionally or alternatively, the main electrical connector can have connectors that include a slider. This allows the respective cable strands to be locked to the connector. Such a slider can provide additional security against unintentional disconnection or against environmental influences.

[0035] This compact arrangement allows the parking brake connections and the main connector, for example, to be accessed via a single wiring harness. This facilitates easier assembly, repair, and additional or alternative maintenance. This arrangement also enables a particularly clear layout of the entire system.

[0036] According to one embodiment of the invention, the valve block has a fourth pneumatic connection designed to connect the parking brake valve device to the trailer's braking system. The fourth pneumatic connection is arranged on the housing side of the housing. The fourth pneumatic connection can be designed to be identical or substantially identical to the other pneumatic connections. The fourth pneumatic connection can be designed to control a parking brake function. For example, the fourth pneumatic connection can be connectable to a control circuit for the trailer's parking brake function. For example, the fourth pneumatic connection can be connected to a spring part of a tri-stop cylinder of the braking system. A tri-stop cylinder can, for example, be designed to keep a brake applied without pressure.Alternatively, the fourth pneumatic connection can also be used to control the parking brake function, for example by pneumatically controlling the parking brake valve device.

[0037] According to one embodiment of the invention, the valve block has a hydraulic vent, which is arranged at an upper end of the housing and faces a front side of the housing. The hydraulic vent can be provided by a vent screw. The hydraulic vent can form a longitudinal axis, which can be directed obliquely towards a center of the valve block and which alternatively or additionally extends in a plane which, in the installed state, is formed by the forward-backward direction and left-right direction of the work machine. The hydraulic vent can be arranged next to, additionally or alternatively above the hydraulic connection. The hydraulic vent can also be formed in a part forming the hydraulic connection. The hydraulic vent can be provided integrated into a component which has the hydraulic connection.The hydraulic vent can be additionally or alternatively located on the housing side of the valve block. The hydraulic vent is designed to vent the hydraulic connection and additionally or alternatively hydraulic lines. In particular, the hydraulic vent is designed to allow air to escape from the hydraulic circuit of the valve block.

[0038] By providing a hydraulic vent, the valve block's hydraulic circuit can be ensured to function properly. The arrangement described above also makes this easy to access in the assembled state. Furthermore, the arrangement toward a center plane of the valve block can protect the vent from environmental influences. For example, such environmental influences can include stone chips, which could damage the vent. In addition, this arrangement can protect the hydraulic vent from accidental breakage by a user.

[0039] According to one embodiment of the invention, the valve block has a drainage system arranged on an underside of the housing. The drainage system can be designed to allow water to escape from the pneumatic lines of the valve block. Additionally or alternatively, the drainage system can also have a vent to release pressure from the pneumatic lines of the valve block. For this purpose, the drainage system can also have a silencer to reduce venting noise. Furthermore, the drainage system can be covered by a protective cap and alternatively or additionally have the protective cap. The protective cap can be arranged on the underside of the housing. The protective cap can protect the drainage system from environmental influences, such as water jets or stone chips. The protective cap can also have a sound-damping function.The protective cap can also provide protection from environmental influences for other pressure compensation devices in the valve block. For example, it can protect a pressure compensation bore of a pressure sensor.

[0040] The valve block can have a pressure sensor configured to detect a pressure in the second pneumatic connection. The pressure sensor can be connected to a pneumatic sensor pressure line of the housing. Furthermore, the housing can form a pressure equalization channel, which can be connected to the pressure sensor and provides it with ambient pressure. The pressure equalization channel can be connected to an opening in the housing, which can be arranged, for example, under the protective cap and alternatively or additionally on an underside of the housing. The pressure equalization channel can be oriented at an angle downward to improve water drainage. This eliminates the need for additional sealing.

[0041] The drainage described above ensures the most trouble-free operation of the valve block's pneumatic lines. The protective cap described above also provides environmental protection for pressure equalization devices and other similar devices. This also enables the most trouble-free operation of the valve block.

[0042] According to one embodiment of the invention, the valve block has a sensor connection for a sensor for detecting a hydraulic pressure in the hydraulic connection. The sensor connection is arranged on a side of the housing facing away from the housing side. This can be a rear side of the housing. Alternatively, the sensor connection can also be arranged on a different side of the housing, for example on the front. The sensor connection can be integrated into a component forming the hydraulic connection. This component can also be connected to the hydraulic vent and thus be vented. The sensor connection can enable the transmission of sensor data from the sensor to the control device. Furthermore, a longitudinal axis of the hydraulic connection can be arranged offset from the axis, i.e. parallel but not coaxial, to a longitudinal axis of the sensor connection.

[0043] The sensor connection described above enables the detection of hydraulic pressure. This can enable safe operation, for example, through continuous monitoring of hydraulic pressure.

[0044] According to one embodiment of the invention, the housing has a main part and a cover element. The main part has, for example, a main element and a closing element, which are connected to one another. A seal can be arranged between them, which seals off respective connecting lines formed through the housing from one another. Seals can also be provided between the closing element and the cover element, as well as between the main element and the cover element. The cover element and the main part can, for example, be connected to one another. The relay valve can be arranged in the main element. The first pneumatic connection, the second pneumatic connection, and the hydraulic connection can be arranged on the closing element. The main electrical connection and, alternatively or additionally, the pneumatic valve device can be arranged on the cover element.The main part can be a part of the housing that essentially provides the pneumatic connections between the valves. The main element can, for example, have an internal labyrinth shape and can be a cast or milled part. The main element can form a rear side of the housing. The main element can further define a first sub-housing interior in which the pneumatic additionally or alternatively hydraulic connections are located. Furthermore, the main part or specifically the end element can form respective hydraulic connections. The protective cap described above, which covers the drainage, can be arranged on a lower side of the main element. The main element can be connected to the end element along a center plane that is parallel to a front side of the housing and extends through the housing.

[0045] The closure element can be arranged in front of the main element and thus form a front side of the housing. The parking brake valve device, or at least its first parking brake valve and its second parking brake valve, can also be arranged in the closure element. The parking brake valves can protrude into the main element. The main element can also be connected to the closure element via screws and, alternatively or additionally, via adhesives or other connecting means. The main element, for example, is in contact with the cover element on the left side.

[0046] The cover element can cover the pneumatic valve device. Furthermore, the cover element can cover electronic components of the valve block. The cover element can further define a further sub-housing interior in which electronic components can be arranged. This further sub-housing interior can be sealed watertight from the environment. The further sub-housing interior can also be substantially airtight from the environment. The further sub-housing interior can be in contact with ambient air via a pressure equalization device in order to equalize pressure. The cover element can have the main electronic connector. Furthermore, the pressure sensor can be arranged in the cover element. The cover element can be arranged on a left side of the main element. The main element and the cover element can be connected along a side that extends from a front to a rear of the housing.

[0047] The above-described combination of a main element, a cover element, and a closure element allows for a particularly simple design and assembly of the valve block. Furthermore, the design of the main element and closure element allows for an integrated function of the housing. This reduces the number of required components. Furthermore, costs and assembly time can be saved, and malfunctions can be reduced.

[0048] The pressure sensor of the valve block, which is designed, for example, to detect the pressure at the second hydraulic connection, can be connected to a sensor pressure line of the housing. The pressure sensor can be arranged in a sensor bore of the housing. To prevent water from accumulating in the sensor bore and, alternatively or additionally, on the pressure sensor, a widened portion can be provided between the pressure sensor and the sensor pressure line, at the bottom of which water can collect. The widened portion can have a larger diameter than the sensor bore and, alternatively or additionally, the sensor pressure line. The sensor pressure line can also be inclined towards an underside of the valve block so that water drains downwards from the pressure sensor. The underside can point downwards in the vertical direction of the vehicle when the valve block is in the installed position.

[0049] One or all of the pneumatic connections in the housing can be free of perpendicular or large airflow deflections. For example, a pneumatic connecting line extends diagonally between the relay valve and a redundant changeover valve. The airflow is deflected twice by approximately 45°. This avoids large deflections and enables a particularly efficient airflow with low turbulence.

[0050] A second aspect relates to a work machine which is designed to connect a trailer having a braking system to it. The work machine has a valve block according to the first aspect. Respective advantages and further features can be derived from the description of the first aspect, wherein embodiments of the first aspect also form embodiments of the second aspect and vice versa. The valve block controls the pressure of the braking system of the connected trailer. The connection between the braking system of the trailer and the valve block can be formed by pneumatic pressure hoses. Furthermore, a connection to pressure sources can also be made via pneumatic hoses. These can be arranged on the trailer and additionally or alternatively on the work machine. The connection between the trailer and the work machine and the corresponding connections of the valve block can be detachable.

[0051] The housing side of the valve block housing extends, for example, in the vertical direction of the work machine. The housing side can, for example, face the left or right side of the work machine. The described arrangement of the work machine and the trailer enables particularly easy access to the valve block. Furthermore, maintenance of the valve block is simplified because the described functions are consolidated in one location and designed for easy access.

[0052] A third aspect relates to a tractor combination comprising the work machine according to the second aspect and a trailer connected to the work machine. The trailer has a braking system. Respective advantages and further features can be found in the description of the first and second aspects, with embodiments of the first and second aspects also constituting embodiments of the third aspect, and vice versa. Short description of the characters Fig. 1 is a diagram illustrating a valve block for a work machine according to an embodiment of the present invention. Fig. 2 schematically illustrates in an isometric view a spatial design of the valve block according to Fig. 1. Fig. 3 schematically illustrates in a front view the valve block according to Fig. 2. Fig. 4 schematically illustrates in a sectional view an arrangement of a pressure sensor with a sensor pressure line in the valve block according to Fig. 2. Fig. 5 schematically illustrates in a perspective view a protective cap for an electrical connection of the valve block according to Fig. 2. Fig. 6 schematically illustrates in a plan view a hydraulic venting of the electrical connection of the valve block according to Fig. 2, on which the protective cap according to Fig. 5 is arranged. Fig. Figure 7 shows schematically in plan view the valve block according to Fig. 2. Fig. Figure 8 illustrates in a sectional view details of a valve seat of a valve of the valve block according to Fig. 2. Fig. 9 schematically illustrates in a sectional view an optimized line geometry in the valve block according to Fig. 2. Fig. 10 schematically illustrates a pressure equalization channel for a pressure sensor. Detailed description of embodiments

[0053] Fig. 1 illustrates a diagram of a valve block for a work machine according to an embodiment of the present invention, with a physical spatial design of the valve block being illustrated in the remaining figures. The valve block is designed for the controlled pressurization of a braking system of a trailer connected to the work machine. The valve block has a pneumatically controlled relay valve 10, which is designed to control the pressurization of the braking system of the trailer while driving. In addition, the valve block has an electrically controlled pneumatic valve device 20, wherein the pneumatic valve device 20 is designed to control the relay valve 10. For this purpose, the pneumatic valve device 20 has a pilot valve 22, an outlet valve 24, and an inlet valve 26, which can be electrically controlled by means of a control device 50 of the work machine.The pilot valve 22 is designed as an electrically controlled 3 / 2-way valve, which is open in its normal position. The outlet valve 24 is designed as an electrically controlled 2 / 2-way valve, which is open in its normal position. The inlet valve 26 is also designed as an electrically controlled 2 / 2-way valve, but is closed in its normal position.

[0054] The valve block has a hydraulically controlled redundancy valve device 30, which is designed to control the pressure of the trailer's braking system in the event of a control failure by the pneumatic valve device 20. This can be the case, for example, if the control device 50 fails. The redundancy valve device 30 has a redundancy relay valve 32, a pressure activation valve 34, and a redundancy changeover valve 36. The redundancy relay valve 32 is a hydraulically controlled relay valve. The pressure activation valve 34 is designed as a 3 / 2-way valve, which in its basic position is connected to a drain 60, through which pressure can be released to the environment. The redundancy changeover valve 36 is a changeover valve that directs pressure to an output when pressure is present at one of its two inputs. The redundancy changeover valve 36 forms a fluidic OR circuit here.

[0055] In one embodiment, as shown here, the valve block also has a parking brake valve device 40, which is designed to control a parking brake function in the trailer's braking system. The parking brake valve device 40 has an electrically controlled first parking brake valve 42 and an electrically controlled second parking brake valve 44. The two parking brake valves 42, 44 are designed as 3 / 2-way valves with a closed basic position. The parking brake valve device 40 also has a parking brake changeover valve 46.

[0056] The valve block has a first pneumatic connection 70, which is designed to connect the relay valve 10 to a pressure source of the work machine. For example, an accumulator and, alternatively or additionally, a compressor of the work machine can be connected to the first pneumatic connection 70. The respective components of the valve block are supplied with pneumatic pressure from the first pneumatic connection 70.

[0057] In addition, the valve block has a second pneumatic connection 72, which is designed to connect the valve block to the trailer's braking system. The second pneumatic connection 72 thus forms an output line of the valve block.

[0058] In one embodiment, the valve block, as shown here, also has a third pneumatic connection 74. The third pneumatic connection 74 is designed to connect the relay valve 10 to a pressure source of the trailer. This allows additional compressed air to be provided redundantly from a second pressure source.

[0059] Furthermore, the valve block has a first main electrical connection 76, which is designed to connect the pneumatic valve device 20 to the control device 50 of the work machine. Via the main electrical connection 76, respective valves 22, 24, 26 of the pneumatic valve device 20 can be controlled by the control device 50. The valve block also has a pressure sensor 80, by means of which an output pressure at the second pneumatic connection 72 can be detected. The output pressure is transmitted from the pressure sensor 80 to the control device 50. For this purpose, the pressure sensor 80 is electrically connected to the control device. The connection can be provided, as shown here, via the main electrical connection 76 or via a separate electrical connection. The pressure detection allows the actuation of the trailer's braking system to be monitored and controlled.

[0060] The valve block also has a hydraulic connection 81, which is designed to connect the redundancy valve device 30 to a hydraulic control circuit of the work machine. This allows a hydraulic control pressure to be applied to the redundancy valve device 30.

[0061] The valve block further includes an electrical first parking brake connection 77, which is designed to connect the first parking brake valve 42 to the control device 50 of the work machine. The valve block also includes an electrical second parking brake connection 78, which is designed to connect the second parking brake valve 44 to the control device 50 of the work machine. The two parking brake valves 42, 44 of the parking brake valve device 40 can thus be controlled by the control device 50 via the two parking brake connections 77, 78.

[0062] The valve block also has a valve 82. The first pneumatic connection 70 and the third pneumatic connection 74 are connected via valve 82. This connects the pressure source of the working machine and the pressure source of the trailer to the pneumatic pressure supply of the valve block. If a leak occurs, valve 82 can automatically throttle the connection, thus preventing a failure of the trailer's braking system and, alternatively or additionally, the working machine.

[0063] The valve block has a housing 90, in the interior of which the relay valve 10, the pneumatic valve device 20, the redundancy valve device 30, the valve 82, and the parking brake valve device 40 are arranged. The first pneumatic connection 70, the second pneumatic connection 72, the third pneumatic connection 74, the main electrical connection 76, the first electrical parking brake connection 77, and the second electrical parking brake connection 78 are arranged on one side of the housing 90 and are accessible from the outside. The housing side forms a front side. This makes the valve block compact, easy to install, and can be easily connected to the work machine. The front side of the housing 90 is, for example, Fig. 3. When the valve block is installed in the work machine, the front of the housing 90 extends in a vertical direction of the vehicle and faces one side of the work machine. The respective fluidic connections between the components of the valve block, i.e., its ports and its valves, are formed integrally by the housing 90.

[0064] The parking brake valve device 40 does not pressurize the second pneumatic connection 72 if pressure is present at at least one of the inputs of the parking brake changeover valve 46. For this purpose, the output of the parking brake changeover valve 46 is inversely connected to the relay valve 10. If the output of the parking brake changeover valve 46 is not pressurized, the relay valve is opened to actuate the trailer brake. The parking brake valve device 40 thus has redundant control of the parking brake function, since in the event of a malfunction of one of the two parking brake valves 42, 44, the other of the two parking brake valves 42, 44 continues to pressurize the trailer's braking system. This prevents a sudden activation of the parking brake in the event of a fault.In one embodiment, the two parking brake valves 42, 44 and, alternatively or additionally, the output of the parking brake changeover valve 46 can be connected directly to the trailer's braking system. Such an embodiment can be used, for example, if the trailer's braking system has separate control lines for controlling the parking brake function, as is common, for example, when using Tristop cylinders. In the embodiment shown here, the fourth pneumatic connection 79 is shown for this purpose, which is designed to connect the parking brake valve device 40 to the trailer's braking system. The fourth pneumatic connection 79 is also arranged on the front of the housing. The fourth pneumatic connection 79 can also be used to connect the relay valve 10 to a device external to the valve block, which can enable external control of the parking brake function.

[0065] The inlet valve 26 of the pneumatic valve device 20 releases a pressure supply to the pneumatic valve device 20 when energized. In the event of a fault, for example, if the control device 50 fails, the inlet valve 26 closes, thus preventing incorrect control of the relay valve 10 and thus also of the trailer's braking system. In addition, the pneumatic valve device 20 then activates a connection to the redundant valve device 30, which will be described below. The control line of the relay valve 10 from the pneumatic valve device 20 is vented in the event of a fault. During normal operation, however, the pneumatic valve device 20 controls the position of the relay valve 10 and thus the actuation of the trailer's braking system.

[0066] In the event of a fault, for example if the control device 50 fails, the pilot valve 22 opens and thus pressurizes a control line of the pressure activation valve 34. This connects an input of the redundancy relay valve 32 to the two pressure sources, i.e. the first pneumatic connection 70 and the third pneumatic connection 74. The hydraulic control of the redundancy relay valve 32 can be used to adjust how much of this pressure is passed on. An output of the redundancy relay valve 32 is connected to the redundancy changeover valve 36. The redundancy changeover valve 36 connects both an output of the relay valve 10 and the redundancy relay valve 32 to the second pneumatic connection 72 and thus to the trailer's braking system. A higher pressure present at the inputs of the redundancy changeover valve 36 is thus used to actuate the trailer's braking system.If the electrical control fails, hydraulic control is enabled.

[0067] Fig. 2 schematically illustrates an isometric view of the valve block. In addition to the front of the housing 90, the isometric view also shows a top side and partially a right side of the valve block. The housing 90 of the valve block has a cover element 116 and a main part 118. The main part 118 is formed from a main element and a closure element attached to the front. Respective valve seats for the valves are formed in the main element. The cover element 116 is arranged on the left side of the housing 90. The main electrical connection 70 is arranged on the cover element 116. The main electrical connection 70 is arranged at a lower end of the cover element 116. The four pneumatic connections 70, 72, 74, 79 and the two electrical parking brake connections 77, 78 are arranged on the main part 118 and formed by the closure element.

[0068] The first pneumatic connection 70 is located on the right side of the main part 118 and is lower than the other pneumatic connections. Left and right are in relation to the graphic representation in Fig. 2 and Fig. 3. Likewise, the designations above and below are to be understood in relation to the representation of the Fig. 2 and Fig. 3, wherein a top side of the housing in the work machine faces upward in the vertical direction of the vehicle. The second pneumatic port 72 is arranged above the other pneumatic ports and is arranged in a lateral direction between the third and fourth pneumatic ports 74, 79. The third pneumatic port 74 is arranged next to the parking brake ports 77, 78. The fourth pneumatic port 79 is arranged to the left below the second pneumatic port 72. This is the leftmost port and closest to the cover element 116.

[0069] The two parking brake connectors 77, 78 are arranged on a lower left side of the main part 118. The two parking brake connectors 77, 78 have connection openings that extend at an angle from the front. The connection opening formed by the two parking brake connectors 77, 78 points to the left and thus in the direction of the cover element 116 or the main electrical connector 76. The remaining connectors on the front of the housing 90 form a connection opening that each points forward. The opening of the first parking brake connector 77 points straight to the left and thus essentially in a horizontal direction towards the cover element 116. The opening of the second parking brake connector 78 is rotated downward relative to the orientation of the opening of the first parking brake connector 77. This allows the two parking brake connectors 77, 78 to be arranged closer together.In addition, connection of a common wiring harness for connecting them to the control device 50 is facilitated.

[0070] On the right side of the main part 118, the contour of the redundant valve device 30 can be seen. This is formed by several cylinders that become narrower from top to bottom, following the shape of the corresponding valves and components below the closure element. Above this section, a cover can be seen, which is arranged above the closure element and forms an element of the main part 118. The hydraulic connection 81 is formed on this element of the main part 118, as well as a hydraulic vent 122, which is formed by a vent screw. On the rear of this element of the main part 118, a connection for a hydraulic pressure sensor 131 is formed. An opening of the connection for the hydraulic pressure sensor 131 is offset axially from the opening of the hydraulic connection 81, which allows the valve block to be very compact.

[0071] Fig. 3 schematically illustrates a front view of a valve block from Fig. 2 for a work machine according to an embodiment of the present invention. The object shown corresponds to the Fig. 2. In contrast to Fig. 2, the parking brake connections 77, 78 are additionally marked by a dashed line each to better understand their position and orientation. A protective cap 128 is arranged at the lower end of the valve block. The protective cap 128 protects a venting device and the drain 60 of the valve block from external influences, such as the ingress of dirt and water. As described below with regard to Fig. 9, this protective cap also protects a pressure equalization opening of the pressure sensor 80. In some embodiments, this protective cap can also protect a drainage device from environmental influences.

[0072] The pneumatic connections 70, 72, 74, and 79 have a larger diameter than the hydraulic connection 81. This prevents confusion between the connections.

[0073] Fig. 4 schematically illustrates an arrangement of a pressure sensor 80 with a sensor pressure line 83 in the housing 90. The pressure sensor 80 is in the Fig. 4 shown on the left. To prevent water from accumulating in the sensor bore 124, a widened portion 126 is provided between the pressure sensor 80 and the sensor pressure line 83, at the bottom of which water can collect. The widened portion 126 has a larger diameter than the sensor bore 124 and the sensor pressure line 83. The sensor pressure line 83 is also inclined toward an underside of the valve block so that water drains downward from the pressure sensor 80. The geometry thus provided prevents water from entering the sensor bore 124. Due to the larger diameter, water collects in the widened portion 126 and then drains again via the sensor pressure line 83 due to the inclination. The water can finally drain out of the valve block via a drainage device, here, for example, at the protective cap 128.

[0074] Typically, pressure sensors, such as the one shown here, are oriented so that the sensor bore 124 points downward along the direction of gravity, thus preventing water from entering. However, to enable a particularly compact design, the pressure sensor 80 is oriented horizontally and arranged in the cover element 116 adjacent to the main electrical connection 70.

[0075] The two parking brake valves 42, 44 have a venting device on their associated parking brake connection 77 and 78, respectively. Fig. 5 schematically illustrates a terminal protection cap 129 and in Fig. 6 a rubber disk 130 from the venting device of each parking brake valve 42, 44. The venting device of the parking brake valves 42 and 44 is integrated in the respective parking brake connection 77 and 78 and is designed to allow air to escape from the parking brake valve in its venting position. To prevent the ingress of dirt and water, a respective vent opening is covered by the rubber disk 130. In an unbent state, the rubber disk 130 rests against an opening and protects it from foreign ingress. In a bent state, the rubber disk 130 can bend upwards to allow air to escape. To enable greater flexibility of the rubber disk 130 and thus faster air escape, four slots 136 are provided in the rubber disk 130. The slots 136 in Fig. The connection protection caps 129 shown in Figure 6 are arranged at the front in front of the rubber washers 130. This provides additional protection against water ingress. For example, the connection protection caps 129 prevent a high-pressure water jet from a pressure washer from acting directly on the rubber washers 130 and bending them inward.

[0076] Fig. Figure 7 shows a detailed view of the hydraulic vent 122. Fig. Figure 7 shows a top view of the valve block. As indicated by the dashed lines, the hydraulic vent 122 is angled to the hydraulic connection 81. The hydraulic vent 122 is arranged such that its longitudinal axis points toward the center of the valve block in a left-right direction. As a result, the hydraulic vent 122 does not protrude laterally and is thus better protected from damage. Fig. 7, the center can be a plane that extends into the image plane and divides the valve block into two halves. This plane runs in Fig. 7 from top to bottom, i.e. from the front to the back of the valve block.

[0077] Furthermore, Fig. 7 illustrates by a dashed line 100 an orientation of the opening of the hydraulic connection 81 and by a dashed line 102 an orientation of the opening for the connection of the hydraulic pressure sensor 131 and thus their offset.

[0078] Fig. Figure 8 schematically illustrates in a detailed view the redundancy relay valve 32 with a valve seat 140. The redundancy relay valve 32 comprises a valve piston 138, the valve seat 140, a valve spring 142 and a valve cylinder 144. The valve piston 138 is in Fig. 8 is arranged on the right and has a bore through its center. Air can flow around the valve piston 138. The central bore of the valve piston 138 serves to save weight and avoid air cushions, but does not represent a flow channel. To the left of it, coaxially arranged, is the valve cylinder 144, which also has a bore. Air can flow through the bore of the valve cylinder 144. Air can flow in via an inlet 146. The valve seat 140 rests on the valve cylinder 144 and surrounds a tip of the valve piston 138. The valve spring 142 rests on the valve seat 140 and supports the valve piston 138 and presses it into the open position. In an unloaded position, the valve spring 142 presses the valve piston 138 away from the valve cylinder 144. The valve seat 140 has an adapted geometry to enable the greatest possible air flow through it.In the position shown, the diameter of a free space around the valve piston 138 is nearly constant. Due to the radially outward-facing bulge in the valve seat 140, the valve seat 140 has a minimum distance along its axial extent from the valve piston 138. In a closed state, the valve piston 138 is pressed against the valve cylinder 144, thereby axially displacing both elements. In . Fig. 8, this appears as a shift to the left. This allows air flow from the valve inlet 146 to be directed around the valve cylinder 144 and the valve piston 138.

[0079] Typically, valve seats for similar valves are provided from the housing or a housing component. However, to ensure simple and ergonomic assembly, the valve seat in this embodiment is provided as a separate component. This allows, for example, assembly from only one side.

[0080] Fig. Figure 9 shows a schematic sectional view of an optimized pipe geometry. The view is based on the Fig. 2 and Fig. 3 directions from the left. The valve shown in the center left is the redundancy changeover valve 36. This is located in the main part 118. To the right of it is a line 148, which connects the redundancy changeover valve 36 to the relay valve 10. As shown in Fig. As can be seen in Figure 9, the line 148 extends diagonally between the relay valve 10 and the redundancy changeover valve 36. Between the relay valve 10 to the line 148 and between the redundancy changeover valve 36 to the line 148, the air flow is deflected by approximately 45°. This avoids large deflections of, for example, two times 90° and achieves a particularly efficient air flow with low turbulence. In addition, Fig. 9, the valve recess 150 around the redundancy changeover valve 36 can be seen. This increases the available area for air flow and thus increases the flow capacity of the redundancy changeover valve 36.

[0081] Fig. Figure 10 schematically illustrates a pressure equalization channel 152 for the pressure sensor 80. The pressure sensor 80 compares the pressure in the sensor pressure line 83 with an ambient pressure. The pressure equalization channel 152 is provided to ensure that the detected pressure is compared with the ambient pressure. The pressure equalization channel 152 conducts an ambient pressure from the protective cap 128 to the pressure sensor 80. The protective cap 128 also provides a protective function against the ingress of water or foreign particles. Furthermore, the pressure equalization channel 152 is oriented at a downward angle. Thus, additional sealing is unnecessary. Reference symbol 10 Relay valve 20 Pneumatic valve device 22 Pilot valve 24 Exhaust valve 26 Inlet valve 30 Redundancy valve device 32 Redundancy relay valve 34 Pressure activation valve 36 Redundancy changeover valve 40 Parking brake valve device 42 First parking brake valve 44 Second parking brake valve 46 Parking brake change valve 50 Control device 60 indulgences 70 First pneumatic connection 72 Second pneumatic connection 74 Third pneumatic connection 76 Main electrical connection 77 First parking brake connection 78 Second parking brake connection 79 Fourth pneumatic connection 80 pressure sensor 81 Hydraulic connection 82 Valve 83 Sensor pressure line 90 housings 100 line 102 Line 116 cover element 118 Main part 122 Hydraulic venting 124 Sensor hole 126 Widening 128 protective cap 129 Connection protection cap 130 rubber washer 131 Hydraulic pressure sensor 136 slot 138 valve pistons 140 valve seat 142 valve spring 144 valve cylinders 146 Valve inlet 148 Line 150 valve recess 152 pressure equalization channel

Claims

[1] Valve block for a work machine for the controlled pressurisation of a brake system of a trailer connected to the work machine, wherein the valve block has a pneumatically controlled relay valve (10) which is designed to control the pressurisation of the brake system of the trailer, an electrically controlled pneumatic valve device (20), wherein the pneumatic valve device (20) is designed to control the relay valve (10), wherein the valve block has a hydraulically controlled redundancy valve device (30) which is designed to control the pressurisation of the brake system of the trailer in the event of a failure of the control by the pneumatic valve device (20), a first pneumatic connection (70) which is designed to connect the relay valve (10) to a pressure source of the work machine, a second pneumatic connection (72) which is designed toto connect the valve block to the braking system of the trailer, has a main electrical connection (76) which is designed to connect the pneumatic valve device (20) to a control device (50) of the work machine, has a hydraulic connection (81) which is designed to connect the redundancy valve device (30) to a hydraulic control circuit of the work machine, and has a housing (90) with a housing side, wherein the relay valve (10), the pneumatic valve device (20) and the redundancy valve device (30) are arranged in the housing (90) and the first pneumatic connection (70) and the second pneumatic connection (72) are arranged on the housing side of the housing (90), , characterized byin that the housing (90) has a main element, a cover element and a closing element which are connected to one another, wherein the relay valve (10) is arranged on the main element, wherein the first pneumatic connection (70), the second pneumatic connection (72) and the hydraulic connection (81) are arranged on the closing element, and wherein the main electrical connection (76) and the pneumatic valve device (20) are arranged on the cover element (116). [2] Valve block according to claim 1, characterized by that pneumatic connections between the components of the valve block are formed by the housing (90). [3] Valve block according to claim 1 or 2, characterized by that the main electrical connection (76) is arranged on the housing side of the housing (90). [4] Valve block according to one of the preceding claims, characterized bythat the valve block has a third pneumatic connection (74) which is designed to connect the relay valve (10) to a pressure source of the trailer and which is arranged on the housing side of the housing (90). [5] Valve block according to one of the preceding claims, characterized byin that the valve block has a parking brake valve device (40) which is designed to control a parking brake function in the braking system of the trailer, wherein the parking brake valve device (40) has an electrically controlled first parking brake valve (42) and an electrically controlled second parking brake valve (44), wherein the valve block has an electrical first parking brake connection (77) which is designed to connect the first parking brake valve (42) to the control device (50) of the work machine, and an electrical second parking brake connection (78) which is designed to connect the second parking brake valve (44) to the control device (50) of the work machine, wherein the first parking brake connection (77) and the second parking brake connection (78) are arranged on the housing side of the housing (90). [6] Valve block according to claim 5, characterized bythat the main electrical connection (76), the first parking brake connection (77) and the second parking brake connection (78) are arranged to be connected to the control device (50) of the work machine by a common cable harness. [7] Valve block according to claim 5 or 6, characterized by in that the valve block has a fourth pneumatic connection (79) which is designed to connect the parking brake valve device (40) to the braking system of the trailer, wherein the fourth pneumatic connection (79) is arranged on the housing side of the housing (90). [8] Valve block according to one of the preceding claims, characterized by that the valve block has a sensor connection for a sensor (131) for detecting a hydraulic pressure in the hydraulic connection (81), wherein the sensor connection is arranged on a side of the housing (90) facing away from the housing side. [9] Work machine which is designed to be connected to a trailer with a braking system and wherein the work machine has a valve block according to one of the preceding claims, wherein the valve block controls the pressure of the braking system of the connected trailer.

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