Distribution block for a construction machine

Abstract

Distributor block (22) for a fluid system of a construction machine, comprising: a first blocking unit controllable by means of a first control device (30), having an input and an output, which in a blocking position blocks the flow of a fluid and in a free position allows the flow of a fluid; a second locking unit controllable by means of a second control device (32), with an input and an output, which in a locking position blocks the flow of a fluid and in a flow position allows the flow of a fluid; a block input (24) which is fluidically connected to the two inputs of the locking units; a first block output (26) which is fluidically connected to the output of the first locking unit; a second block output (28) which is fluidically connected to the output of the second locking unit and a coupling (34) by means of which the control devices (30, 32) are coupled in order to actuate the controllable locking units simultaneously.

Description

[0001] The present invention relates to a distribution block for use with a construction or work machine.

[0002] Construction machinery is often equipped with hydraulic circuits to operate various accessories and attachments. For example, a backhoe bucket is usually hydraulically operated.

[0003] Construction machines often lack sufficient auxiliary hydraulic circuits for hydraulic attachments. In this case, the hydraulic circuit used to operate the bucket cylinder is also used to operate hydraulic attachments.

[0004] The bucket cylinder is required for bucket operation. If, for example, a grapple is to be used, the bucket cylinder is not needed. In this case, the bucket cylinder is preferably fully retracted to prevent damage to an additional device or attachment and to ensure proper function of the attachment. For this purpose, it is common practice to install 3-way ball valves on the excavator arm. One ball valve closes off the bottom side of the bucket cylinder, and the other ball valve closes off the rod side of the bucket cylinder from the additional device, thus decouples the fluid circuit of the bucket cylinder from the bucket cylinder and connects it to the additional device.

[0005] Since the cross-sectional area of ​​the rod side of the bucket cylinder is significantly smaller than the cross-sectional area of ​​the base side, the bucket cylinder acts as a pressure amplifier when pressure is applied from the base side. Thus, if the rod side is blocked and the base side is pressurized, the pressure on the rod side is a factor of 2 to 5 times higher than on the base side. This applies to most hydraulic cylinders.

[0006] In a 3-way ball valve with standard seals, the ball is floating and is shifted toward the lower pressure side depending on the applied pressure conditions. Therefore, the pressure on the closed side must be lower than the pressure on the open side. If the pressure on the closed side is higher, the ball of the 3-way ball valve is pushed toward the open side. This allows fluid to flow around the ball seal.

[0007] In the example of a backhoe, this would result in fluid flowing from the rod end of the bucket cylinder to the tank, causing the bucket cylinder to extend. The ball seal therefore only acts unidirectionally.

[0008] To prevent this unwanted extension, it is known to use so-called 3-way ball valves with bidirectional seals, a so-called all-round sealing system. In this case, the ball is floating and is moved towards the side with the lower pressure according to the pressure conditions. In the all-round sealing system, the ball seal follows the movement of the ball and thus ensures reliable sealing. In other words, in all-round sealing systems, the pressure on the blocked side can be greater than the pressure on the open side. The disadvantage of 3-way ball valves with all-round sealing systems is that the components of the sealing system can be damaged by pressure pulses, which can lead to leaks. In all-round sealing systems, delicate components, such as O-rings with very thin cross-sections, are often used.Pressure pulses can cause gap extrusion and O-ring failure, or jamming of components, rendering the sealing system less reliable. Examples where pressure pulses can occur include the use of hydraulic hammers, soil compactors, and grapples.

[0009] To achieve a design resistant to pressure pulses, it is known to use a 3-way ball valve with a so-called plug shaft. A plug shaft specifically means that the control shaft and ball form a single unit, with the plug shaft supported on both sides, i.e., at the top and bottom. The seals used in this ball valve are bidirectional, with the ball valve having a ball seal at each connection. The main disadvantage of this solution is its high cost.

[0010] A disadvantage of 3-way ball valves is the arrangement of the inlets and outlets. The outlets are each offset by 90° from the inlet. This requires complex hose and / or piping with elbows to route the hose and / or piping parallel to the excavator arm.

[0011] A disadvantage of 3-way ball valves is their attachment to the excavator arm. Base plates with mounting holes often have to be welded to the ball valve housing. This results in increased manufacturing costs and an increase in overall height. The present invention is based on the technical problem of creating a device that can function like a 3-way ball valve and mitigates at least one of the aforementioned disadvantages. In particular, the device should be resistant to pressure pulses, have a bidirectional sealing system, and be cost-effective to manufacture. Furthermore, it should particularly preferably be possible to install hoses and / or piping around an axis, while the device should be technically easy to attach to a carrier device.

[0012] This problem is solved by a distribution block according to claim 1 and a system according to claim 9.

[0013] The distribution block for a fluid system of a construction machine has a first blocking unit that can be controlled by a first control device and has an inlet and an outlet. The blocking unit blocks the flow of a fluid in a blocking position and allows the flow of a fluid in a flow-through position. Flow is understood, in particular, to mean the passage or blocking of a fluid between the inlet and the outlet of the blocking unit. The blocking unit can therefore be considered a type of controllable shut-off valve.

[0014] The distribution block further comprises a second blocking unit designed analogously to the first blocking unit.

[0015] A block inlet is fluidically connected to the two inlets of the blocking units. A block inlet is understood to be a connection point for a line in a fluid circuit.

[0016] The distribution block further comprises a first and a second block outlet, wherein the two block outlets are each fluidically connected to an outlet of a blocking unit. In a particularly preferred embodiment, the block outlets are formed by the outlets of the blocking units.

[0017] Furthermore, the distribution block comprises a coupling by means of which the control devices of the locking units are coupled to one another in order to actuate the locking units simultaneously in a predefined manner determined by the coupling. The coupling can preferably be mechanical. It is understood that an electrical, in particular electromechanical or fluidic, coupling is also conceivable.

[0018] The distribution block or a switchover valve can be created using two cost-effectively manufactured 2-way blocking units, particularly 2-way ball valves. In particular, 2-way blocking units make it technically easy to create a sealing system that seals bidirectionally and is resistant to pressure pulses. By coupling the control devices of the two blocking units, operating errors can be reliably eliminated. Furthermore, the distribution block can be used in a manner identical to a 3-way ball valve. In particular, this creates a solution that, like a 3-way ball valve, can be directly integrated into a hydraulic circuit without the need for adaptation. Thus, a replacement device for a 3-way ball valve can be created that does not have the disadvantages of 3-way ball valves.

[0019] In a preferred embodiment, the block inlet is located on the inlet side of the distribution block opposite the block outlets, allowing for the distribution block to be installed with hoses and / or piping in a single axis. This allows the distribution block to be integrated into a hydraulic circuit efficiently and in a space-saving manner. Furthermore, a hydraulic circuit with fewer deflections and kinks can be created, thus creating a hydraulic circuit with increased efficiency.

[0020] In an advantageous embodiment, the distribution block has an additional block inlet, particularly preferably two additional block inlets. The block inlets are located in particular on opposite long sides of the distribution block. The block inlet and the block outlets are therefore preferably oriented axially parallel to one another, whereas the additional block inlets are aligned essentially perpendicular thereto. By providing one or two additional block inlets, a highly variable, multifunctional distribution block can be created. In particular, it is conceivable to connect measuring devices or an additional hydraulic circuit to the additional inlets. The block inlet can be freely selected, either on the same axis as the block outlets or perpendicular to them. Unused block inlets can be closed with a plug.

[0021] It goes without saying that, depending on the installation position, the position of a single block inlet can be determined by closing off the other block inlets. In particular, the block inlet can advantageously be closed off by a full-surface block housing at the block inlet. It goes without saying that individual block outlets can also be closed off with plugs, thus determining the optimal installation position of the distribution block during installation and subsequently configuring it on-site.

[0022] In a further advantageous embodiment, the control devices of the controllable locking units are coupled by means of two intermeshing gear stop plates. This allows for a robust and efficient coupling of the two control devices. In particular, gear stop plates allow the mobility of the control devices to be restricted to a permissible range. This increases the longevity of the distribution block and effectively counteracts incorrect operation.

[0023] In a particularly preferred embodiment, the distribution block is configured to alternately open and / or close the block outlets by means of the coupling. The coupling can thus cause only one block outlet to be open, while the other block outlet is closed. This allows the distribution block to efficiently replicate the operation of a 3-way ball valve.

[0024] In a further preferred embodiment, the distribution block is configured to open or close both block outlets simultaneously by means of the coupling. This allows the application range of the distribution block to be expanded and creates a multifunctional distribution block suitable for use in a variety of hydraulic applications.

[0025] Particularly preferably, the distributor block comprises a block housing in which fluid channels are formed, wherein the inlets of the two controllable blocking units are fluidically connected to the block inlet via the fluid channels. This makes it possible to create a block housing that offers both protection against contamination and enables fluid connections. A cost-effective distributor block can be created that can be constructed using a few components.

[0026] In a particularly preferred embodiment, the controllable blocking units are each designed as ball valves, in particular as 2-way ball valves. This allows for the creation of an extremely cost-effective device, since the ball valve components can be constructed based on standard components for 2-way ball valves and can therefore be manufactured in large quantities and consequently cost-effectively. The blocking unit is preferably designed as a 2-way ball valve. The sealing system used in the 2-way ball valve is bidirectionally sealed in the blocked position. The sealing system used in the 2-way ball valve is insensitive to pressure pulses. Due to the simple and robust design, the components are not damaged when pressure pulses occur.

[0027] Particularly preferably, the distribution block comprises a block housing with two mounting holes for attachment to the excavator arm. This allows the distribution block to be designed with a low overall height.

[0028] In a particularly preferred embodiment of the system, a line and / or a measuring device is connected to an additional block inlet of the distribution block. This can increase the functionality of the system. The use of a measuring device makes it possible to monitor the correct operation of the fluid system without having to use an additional line. Furthermore, by connecting a line to the system's distribution block, the functionality of the construction machine can be easily expanded.

[0029] Embodiments of the invention are explained below with reference to the accompanying drawings. They show: Fig. 1 is a schematic representation of a system comprising an excavator and a hydraulic circuit; Fig. 2 a schematically simplified representation of a distribution block in plan view; Fig. 3 schematically shows a possible hydraulic circuit symbol of the distribution block according to Fig. 2; Fig. 4a another variant of a distribution block in plan view; Fig. 4b a section through the distribution block according to Fig. 4a; Fig. 4c another section through the distribution block according to Fig. 4a; Fig. 5 an exemplary hydraulic circuit with a hydraulic cylinder with two 3-way ball valves; and Fig. 6 the circuit according to Fig. 5, with two distribution blocks.

[0030] In Fig. Figure 1 schematically shows a system 10 comprising a backhoe 11 and a hydraulic circuit (not further identified). The backhoe 11 has an excavator arm 12, on which a bucket 14 is mounted.

[0031] The bucket 14 can be operated by means of a bucket cylinder 16, with the hydraulic circuit having two 3-way ball valves 18 and connections for additional equipment 20. In this respect, the design of the system 10 corresponds to the state of the art.

[0032] If a distribution block 22 is used in the system 10 instead of the 3-way ball valve 18, the system 10 shown corresponds to a system 10 according to the invention.

[0033] In the figure, this is indicated by a slash at reference numerals 18 and 22.

[0034] In Fig. 2 shows a schematically simplified representation of a distribution block 22.

[0035] The distribution block 22 has a block inlet 24. A first block outlet 26 and a second block outlet 28 are arranged on the side of the distribution block 22 opposite the block inlet 24.

[0036] The distribution block 22 further comprises a first control device 30 for controlling a controllable first locking unit (not shown) and a second control device 32 for controlling a second locking unit (not shown).

[0037] The two control devices 30, 32 are connected by a coupling 34. In the example shown, the block inlet 24 is fluidically connected to the blocking units (not shown) by means of fluid channels formed in a block housing 23. Actuation of the control devices 30, 32 enables or blocks flow to the associated block outlet 26, 28. This is illustrated in the figure by the various positions of the control devices 30, 32.

[0038] In the example shown, the coupling 34 is schematically represented by a traction mechanism. It is understood that other coupling types are conceivable.

[0039] The distribution block 22 may also have further block inputs, which are designated 24a and 24b and are shown in dashed lines.

[0040] In Fig. 3 is a circuit symbol 36 for a distribution block 22, in particular the distribution block 22 according to Fig. 2, shown schematically.

[0041] The distribution block 22 is formed from two 2-way ball valves 38, 40, with the inlets of the 2-way ball valves 38, 40 being fluidically connected to the block inlet 24. In the example shown, the other block inlets 24a, 24b are closed by plugs, so that the distribution block 22 comprises only a single block inlet 24.

[0042] Also schematically shown is the coupling 34, which connects the two control devices 30, 32 to each other in such a way that the 2-way ball valves 38, 40 are alternately opened and closed. This means that if the first 2-way ball valve 38 is open, the second 2-way ball valve 40 is closed, and vice versa.

[0043] It is understood that embodiments are also conceivable in which both ball valves 38, 40 can be closed and opened simultaneously.

[0044] In Fig. 4a shows a more detailed illustration of an alternative embodiment of a distribution block 22. In contrast to the Fig. In the embodiment shown in Figure 2, the coupling 34 is configured by two gear stop discs. This ensures, on the one hand, that the two control devices 30, 32 are always actuated simultaneously. On the other hand, the stop effectively counteracts incorrect operation due to excessive rotation.

[0045] In the Fig. 4a, the further block inlets 24a, 24b of the distribution block 22 are closed by plugs, so that the distribution block 22 according to Fig. 4a has a block inlet 24. It is understood that the plugs inserted into the further block inlets 24a, 24b can also be easily removed to release another block inlet.

[0046] Furthermore, the Fig. 4a shows the fluid connections between the block inlet 24 and the blocking units (not shown in detail) in dashed lines. These fluid connections are formed by fluid channels formed in the block housing 23 of the distribution block 22.

[0047] In Fig. 4b is a section through the distribution block 22 according to Fig. 4a is shown in plan view, with the section running approximately centrally through the distribution block 22. The two 2-way ball valves 38, 40, each mounted or sealed with seals 42, are shown in more detail. In the setting shown, the first 2-way ball valve 38 is switched in the blocking direction, so that no fluid is directed from the block inlet 24 to the first block outlet 26.

[0048] The second 2-way ball valve 40 is switched to the open position so that fluid is directed from the block inlet 24 to the second block outlet 28.

[0049] It is understood that the inputs and outputs can be used synonymously. The chosen designation serves to better understand the invention. A person skilled in the art will recognize that an input can also serve as an output and vice versa. Fig. Figure 4c shows a side view of a section through the distribution block 22 and the second 2-way ball valve 40 contained therein. The same reference numerals refer to the same features and will not be explained again.

[0050] This sectional view illustrates a further advantage of gear stop discs as coupling 34. The flat gear stop discs operate mechanically reliably and require little installation space, allowing the creation of an overall flat distribution block 22, which can be advantageously attached to an excavator arm, for example.

[0051] Furthermore, the figure shows a fluid channel 44 which is formed in the block housing 23 by a corresponding geometry of the block housing 23.

[0052] In Fig. 5 shows a simplified schematic representation of a hydraulic circuit 46. The hydraulic circuit 46 comprises a hydraulic cylinder, for example, a bucket cylinder 16 of a backhoe, and two 3-way ball valves 18, one 3-way ball valve 18 being connected to a rod side of the hydraulic cylinder and one 3-way ball valve 18 being connected to a bottom side of the hydraulic cylinder.

[0053] As already explained above, such a connection of the hydraulic cylinder can lead to high pressure conditions at the inlets of the 3-way ball valves 18 and adversely affect the tightness of the 3-way ball valves 18 when they are switched to the blocking position.

[0054] In Fig. 6, the hydraulic circuit 46 is shown in Fig.5, wherein distribution blocks 22 are integrated instead of the 3-way ball valves 18. This illustrates that the distribution blocks 22 can be easily integrated into a hydraulic circuit 46 instead of 3-way ball valves 18. In particular, the distribution blocks 22 can be integrated into a hydraulic circuit 46 instead of 3-way ball valves 18 without significant modifications.

[0055] The invention has been comprehensively described and explained with reference to the drawings and the description. The description and explanation are to be understood as exemplary and not restrictive. The invention is not limited to the disclosed embodiments. Other embodiments or variations will become apparent to those skilled in the art upon use of the present invention and upon careful analysis of the drawings, the disclosure, and the following claims.

[0056] In the claims, the words "comprising" and "having" do not exclude the presence of further elements. The undefined article "a" or "an" does not exclude the presence of a plurality. A single part, element, or unit can perform the functions of several of the units recited in the claims. The mere reciting of some measures in several different dependent claims should not be understood to mean that a combination of these measures cannot also be used advantageously. Reference signs in the claims are not to be understood as limiting. Reference symbol 10 systems 11 backhoes 12 excavator arm 14 spoons 16 bucket cylinders 18 3-way ball valve 20 Connection for additional devices 22 Distribution block 23 block housings 24 Block entrance 26 first block exit 28 second block exit 30 first control device 32 second control device 34 Coupling 36 circuit symbols 38 first 2-way ball valve 40 second 2-way ball valve 42 Seal 44 Fluid channel 46 Hydraulic circuit

Claims

[1] Distribution block (22) for a fluid system of a construction machine, comprising: a first blocking unit controllable by means of a first control device (30), having an inlet and an outlet, which in a blocking position blocks a flow of a fluid and in a passage position allows a flow of a fluid; a second blocking unit, controllable by means of a second control device (32), having an inlet and an outlet, which blocks a flow of a fluid in a blocking position and allows a flow of a fluid in a passage position; a block inlet (24) which is fluidically connected to the two inlets of the blocking units; a first block outlet (26) fluidly connected to the outlet of the first blocking unit; a second block outlet (28) which is fluidly connected to the outlet of the second blocking unit and a coupling (34) by means of which the control devices (30, 32) are coupled in order to actuate the controllable locking units simultaneously. [2] Distribution block (22) according to claim 1, wherein the block inlet (24) is arranged on an inlet side of the distribution block (22) opposite the block outlets (26, 28), so that a hose and / or piping of the distribution block (22) in one axis is possible. [3] Distribution block (22) according to one of the preceding claims, with a further block inlet (24a), preferably two further block inlets (24a, 24b), which are particularly preferably arranged on opposite longitudinal sides of the distribution block (22). [4] Distribution block (22) according to one of the preceding claims, wherein the control devices (30, 32) of the controllable locking units are coupled by means of two intermeshing gear stop discs. [5] Distribution block (22) according to one of the preceding claims, wherein the distribution block (22) is designed to alternately open and / or close the block outputs (26, 28) by means of the coupling (34). [6] Distribution block (22) according to one of claims 1 to 4, wherein the distribution block (22) is adapted to open or close both block outputs (26, 28) simultaneously by means of the coupling (34). [7] Distribution block (22) according to one of the preceding claims, wherein the distribution block (22) comprises a block housing (23) in which fluid channels are formed and the inlets of the two controllable blocking units are fluidically connected by means of the fluid channels. [8] Distribution block (22) according to one of the preceding claims, wherein the controllable blocking units are each designed as ball valves, in particular as 2-way ball valves (38, 40). [9] Distribution block (22) according to one of the preceding claims, wherein the block housing of the distribution block (22) has two fastening bores. [10] System (10) comprising a backhoe (11) with an excavator arm (12) and a distributor block (22) according to one of the preceding claims, wherein the distributor block (22) is attached to the excavator arm (12). [11] System (10) according to claim 10 with a distribution block (22) according to one of claims 2 to 8, wherein a line and / or a measuring device is connected to a further block input (24) of the distribution block (22).

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