EP2241762A1 - Control device - Google Patents

Abstract

The device (H) has a rotational circuit (U) with a rotating-directional seated valve (SU) between a pressure source (P) and a reservoir (R). Magnets (M1, M2) actuate a set of directional seated valves (S1, S1', S2, S2') and the rotational circuit. The rotating-directional seated valve is provided in a pass-through position, when the set of valves is in locking position and vice-versa. The magnets divide the rotating-directional seated valve such that the rotating-directional seated valve is actuated either alternately by one of the two magnets or jointly by both magnets.

Description

The invention relates to a control device specified in the preamble of claim 1. Art.

From EP1 574 720 A . Fig. 6 known control device includes a separate recirculating poppet valve for each direction in which the hydraulic motor is controlled. These two circulation poppet valves are arranged in a line loop connecting the pressure source to the reservoir. Each recirculating poppet valve is actuated by the magnet which simultaneously actuates the first and second directional seat valves for that direction to control a direction of the hydraulic motor. If several sections of the control device assigned to a common pressure source, the number of required circulation Wegesitzventile multiplied according to the number of sections. This means high construction costs, considerable space requirements and the integration of a complex circulation loop.

The invention has for its object to provide a control device of the type mentioned, which is cheaper, more compact and easier with the same functionality.

The stated object is achieved with the features of claim 1.

Since in the control device or each section of the control device, the two magnets share only a single recirculating directional seat valve, which works for both directions to be controlled of the hydraulic motor, reduces the construction effort, the controller is more compact, and is the installation of lines simplified. These advantages are achieved without sacrificing the functionality of the control device, for example in a mobile working device.

In one embodiment, the recirculating directional seat valve is actuated by the respective magnet from the passage position into the shut-off position when this magnet actuates the first and second directional seat valves associated with this direction from their shut-off positions into the passage positions. As soon as the recirculating directional seat valve is brought into the shut-off position, the full supply pressure for controlling the desired direction is immediately available. If, however, the magnet is in a de-energized state brought, then the pressure source is connected directly to the reservoir in order to minimize the mechanical stress on the pressure medium, and also to avoid unwanted heat development in the pressure medium.

Suitably, in the de-energized state of both magnets, all the first and second directional seat valves are held in their shut-off positions, and the recirculating directional seat valve remains in the open position, each set by the force of a spring on the directional seat valve.

Alternatively, the operation could also be reversed, d. H. the springs bring the recirculating directional seat valve from the passage position to the shut-off position, and the first and second directional seat valves from their shut-off positions in the passage positions.

Conveniently, the first and second directional seat valves and also the recirculating directional seat valves are 2/2-way seated valves that leak-tight in the shut-off, so that a load is reliably held, and on the other hand quickly reached the high working pressures without leaks at very high working pressures and small flow rates become. Each directional seat valve can seal leak-free in at least one direction of flow, or even in both directions of flow, depending on which switching states are to be expected.

In an expedient embodiment, a non-return valve blocking the pressure source is provided between the pressure source and each first directional seat valve, to which a throttle is assigned. This improves the response of the control device and may be useful if leakproof shut-off directional seat valves are provided in only one flow direction. The check valve with the throttle is useful, for example, to hedge in an operating case in which after an actuation of the hydraulic motor in one direction, the operation aborted and immediately resumed in the same or in the opposite direction.

In a further embodiment, the control device comprises at least two sections connected in parallel with the reservoir and supplied from a common pressure source for at least one hydraulic motor. In this case, in order to adapt the circulation circuit to the several sections, it is expedient for a first pressure line branch to lead from the pressure source only to the reservoir via the recirculating directional seat valves of the sections in order to supply or discharge the supply pressure, irrespective of which section is used. From the first pressure line branch branches off upstream or in the upstream section, for example, a blind-ending second pressure line branch, to which each of the two first directional seat valves of the sections are connected in parallel. This meandering circuit can be realized with little construction effort, and makes it possible to compactly summarize any number of sections.

In another embodiment, the two first and second directional one-way directional valves and the bidirectional common directional directional seat valve are juxtaposed in parallel in a block with the recirculating directional seat valve located midway between the outboard positioned first and second directional seat valves , The two magnets are mounted substantially symmetrically outside the center of the block. At the block, a middle operating lever associated with the recirculating directional seat valve is also supported, as are two outer actuating levers associated with a direction, respectively, of first and second directional seat valves. Of these three operating levers, each magnet acts simultaneously on an outer and the middle operating lever.

It is useful for the optimal use of the magnetic force when the operating lever pivotally mounted on the block angle lever having an operating part for the respective directional seat valve near the pivot bearing and at least one driver part at the free angle lever end, but the middle operating lever two outwardly to both magnets has pointing driver parts, each of which can be acted upon by a magnet, or both of which are acted upon jointly by two magnets.

It may also be favorable if each magnet has an armature tappet with transverse drivers arranged on a tappet part of an external actuating lever and a driver part of the central actuating lever on both tappet outer sides. The dogs are preferably rotatably mounted rollers which minimize wear between the plunger and the operating lever. Furthermore, a more favorable lever arm of the magnetic force is achieved with respect to the pivot bearing, which also allows relatively high actuation forces of the directional seat valves with low magnetic force overcome.

Suitably, furthermore, the control device is connected to an electrical or electronic control, with which for each magnet individually energized or de-energized Condition, or for both magnets simultaneously energized or de-energized states are adjustable. This gives the control device four different switching states. In the first case, both magnets are de-energized. There is no Wegesitzventil operated. The recirculating seat valve is in the open position to connect the pressure source to the reservoir. In the second case, a magnet is brought into de-energized state, that is, the first and second directional seat valves for the related direction of the hydraulic motor are switched to the passage positions, while the Umlaufwegesitzventil is placed in the barrier. By means of the supply pressure of the pressure source, the hydraulic motor is controlled in the desired direction. The other magnet is de-energized. The third case is a reversal of the second case. In the fourth case, both magnets are brought into energized state at the same time, that is, all Wegesitzventile be operated to depressurize the entire system.

Fig. 1

ein Blockschaltbild einer hydraulischen Steuervorrichtung beispielsweise eines mobilen Arbeitsgeräts,

Fig. 2

eine Detailvariante der Steuervorrichtung von Fig. 1,

Fig. 3

eine weitere Ausführungsform, bei der die Steuervorrichtung zwei Sektionen für jeweils mindestens einen Hydromotor umfasst,

Fig. 4

eine Seitenansicht beispielsweise der in eine Blockstruktur integrierten Steuervorrichtung gemäß Fig. 1 oder Fig. 2,

Fig. 5

einen Teilschnitt in der Schnittebene V-V in Fig. 4, und

Fig. 6

eine vereinfachte Draufsicht zu Fig. 4, wobei die in Fig. 4 gezeigten Magneten weggelassen sind.

With reference to the drawings, embodiments of the subject invention will be explained. Show it:

Fig. 1

a block diagram of a hydraulic control device, for example, a mobile working device,

Fig. 2

a detail variant of the control device of Fig. 1 .

Fig. 3

a further embodiment in which the control device comprises two sections for at least one hydraulic motor,

Fig. 4

a side view, for example, of the integrated in a block structure control device according to Fig. 1 or Fig. 2 .

Fig. 5

a partial section in the section plane VV in Fig. 4 , and

Fig. 6

a simplified plan view too Fig. 4 , where the in Fig. 4 shown magnets are omitted.

The in the Fig. 1 to 6 shown embodiments of electro-hydraulic control devices H are useful, for example, for use in portable or mobile devices that control hydraulic motors with extremely high working pressures up to about 450 bar, such as screwdrivers, riveting, building or Brückenversetzvorrichtungen or Schreitrückvorrichtungen and the like. To the device so compact to keep as possible, a pressure source is used, which these high working pressures with relatively small flow achieve. This requires seat valves with leak-free shut-off positions. Since, on the other hand, when the implement is activated, the pressure source possibly delivers continuous operation, the pumped pressure medium, when not in operation, must be conveyed to the reservoir with as little resistance as possible to minimize the mechanical load on the pressure medium and the heat generation. Alternatively, however, the electro-hydraulic control device H can also be used for other purposes. The recirculating seat valve allows either the entire flow rate of the pressure source directly to the reservoir, or alternatively a control pressure in a designated control pressure system, eg. B. a load pressure signal circuit, wherein the delivery rate of the pressure source is then brought to the reservoir when the recirculating directional seat valve is in the passage position and degrades the pilot pressure in the pilot pressure system.

In the Fig. 1 Control device H shown as a block diagram, for example, is incorporated in a mobile implement G and has either a pressure source P and a reservoir, or is connected or connectable to a pressure source P or a reservoir. From the pressure source P, a pressure line 1 extends away, are connected to the parallel pressure line branches 3, 7 and 3 '. The pressure line branch 3 leads to a working line A of a hydraulic motor Z, for example, a double-acting hydraulic cylinder. The pressure line branch 3 'leads to a working line B of the hydraulic motor Z. The pressure line branch 7 leads to a reservoir line branch 8 which is connected to a reservoir line 2 connected to the reservoir R.

The hydraulic motor Z can be actuated in both mutually opposite directions by means of the control device H, for example using an electric or electronic control C, which is connected to a first and a second magnet M1, M2, for example a black-and-white switching magnet. Alternatively, proportional solenoids could also be provided.

In the control device H a total of five 2/2-way seat valves are positioned parallel to each other, which are selectively actuated with the magnets M1, M2 respectively against the force of a spring 10.

A first directional seat valve S1 is connected to the pressure line branch 3. A second directional seat valve S2 '(a load-holding valve) is connected to a line loop 5, which branches off at a node 4 from the working line A, and is connected via a branch line 6 to the reservoir line 2. The first and second directional seat valves S1, S2 'are a direction of the direction control of the hydraulic motor Z assigned, in Fig. 1 the direction to the right.

For the other direction (in Fig. 1 to the left) is connected to the pressure line branch 3 ', a first directional seat valve S1' to selectively supply the working line B with the supply pressure. This direction also includes another second directional seat valve S2, which is arranged in a line loop 5 'branching off from the working line B at a node 4' and connected to the reservoir line 2 via a line branch 6 '. To the pressure line branch 7, a common for both directions of the adjustment of the hydraulic motor Z circulation directional seat valve SU is connected, from which a line branch 8 also leads to the reservoir line 2.

In the in Fig. 1 shown switching position take by the force of springs 10, the first directional seat valves S1, S1 'and the second directional seat valves S2, S2' (the load-holding valves) their shut-off positions, while the common recirculating directional seat valve SU assumes its passage position. The pressure source P is thus connected to the reservoir R via the circulation directional seat valve SU.

The magnet M1, which is switchable via the controller C either in a de-energized state or a powered state, actuates at the in Fig. 1 shown embodiment in energized state at the same time the first and second directional seat valves S1, S2 'and the common recirculating seat valve SU, for controlling the one direction, while the other magnet M2 in the energized state, the first and second directional seat valves S1', S2 and the common Circulating directional seat valve SU actuated for the other direction. The directional seat valves are connected in accordance with this mode of operation by the magnets M1, M2 accordingly.

In an alternative embodiment, not shown, it would be possible to reverse the operation of the directional seat valves, d. h., To hold the first and second directional seat valves S1, S1 ', S2, S2' at non-energized magnet M1, M2 by the springs 10 in the passage position, however, the common circulation directional seat valve SU by the spring 10 to hold in the shut-off position and with energizing the magnets M1, M2 switch accordingly.

The magnets M 1, M2 are either not energized either, or it is energized in each case a magnet M1 or M2, or both magnets M1, M2 are energized. The latter Case is controlled, for example, to make the entire system depressurized, ie, to avoid that locked between the hydraulic motor and one of the directional seat valves in a working line A or B working pressure.

In the embodiment in FIG Fig. 1 are all Wegesitzventile designed so that they assume their leakage-free shut-off only one direction of flow, as indicated by the one-sided symbol 11. Namely, each first directional seat valve S1, S1 'blocks in the flow direction from the pressure source P to the reservoir R, blocks each second directional seat valve S2, S2' in the flow direction to the reservoir R and blocks the common recirculating seat valve SU in the flow direction to the reservoir R. In this case it may be appropriate, as shown, in each pressure line branch 3 and 3 'provide a check valve 12 and a throttle 13, wherein the check valve 12 blocks in the return flow to the pressure source P. This is especially recommended for operating situations in which a control of the hydraulic motor Z was done in one direction, then stopped and immediately resumed, either in the same or in another direction. This could in fact lead to an undesirable pressure build-up in the respective backflow direction which is not blocked by the directional seat valve brought into the blocking position.

In Fig. 1 the three directional seat valves are actuated by a mechanical actuator 9 and 9 'together by the magnet M1, M2, based on the 4 to 6 for an embodiment will be explained.

The embodiment of the electro-hydraulic control device H in Fig. 2 is different from that of Fig. 1 in that all the first and second directional seated valves S1, S1 ', S2, S2' and the common circulation directional seat valve SU are 2/2-way seated valves which shut off in the shut-off position in both directions of flow leakage-free, as by the two symbols 11 'at the first directional seat valve S1 is highlighted. In this case, the respective check valve 12 with the throttle 13 may be omitted if necessary.

The function is in both embodiments of Fig. 1 and 2 largely the same.

Starting from the in Fig. 1 and 2 shown unpressurized states, the pressure source P is first turned on. The pumped pressure medium passes through the circulation path seat valve SU from the pressure line 1 with the lowest possible back pressure directly into the reservoir line 2. The hydraulic motor Z is and is even hydraulically blocked, between the Check valves 12 and acting as load holding valves second directional seat valves S2, S2 '.

To the hydraulic motor Z in Fig. 1 to move to the right, the magnet M1 is energized, which switches the first and second directional seat valves S1, S2 'and the common recirculation directional seat valve SU, so that the pressure medium from the pressure line branch 3 flows into the working line A, and at the same time pressure medium via the working line B and the second directional seat valve S2 'is pushed out to the reservoir R. The circulation Wegesitzventil SU assumes its blocking position, so that the full supply pressure for controlling the hydraulic motor Z is available, and the pressure line branch 7 from the line branch 8 to the reservoir line 2 is isolated.

To the hydraulic motor Z after taking again the starting position according to Fig. 1 or Fig. 2 in the other direction (to the left in Fig. 1 ), the other magnet M2 is brought into the energized state, so that the first and second directional seat valves S1 ', S2 are brought into the passage positions, and the circulation path seat valve SU again assumes the shut-off position. The pressure line branch 3 'is connected to the working line B. Pressure medium, however, is pushed out of the working line A via the node 4, the line loop 5, the second directional seat valve S2 and the line branch 6 in the reservoir line 2.

If the hydraulic motor Z stops again and hydraulically blocked, the in Fig. 1 shown starting position produced.

In order to make the entire system of the control device H depressurized, both magnets M1, M2 are simultaneously brought into the de-energized state, at least for a short time, so that the pressures in both working lines A, B completely degrade (floating position of the hydraulic motor Z).

In the embodiment in FIG Fig. 3 The control device H comprises two sections H1, H2, which use the same reservoir R and the same pressure source P, each section H1, H2 serving, for example, to control the direction of at least one hydraulic motor. The two sections are analogous to Fig. 1 constructed, ie with directional seat valves that can take a leak-free shut-off in a flow direction. Alternatively, sections H1, H2 could be analogous to Fig. 2 be equipped with Wegesitzventilen, in both Shut off flow-through directions without leaks if the shut-off position is set.

Thus, regardless of which section H1 or H2 is used, or whether both sections H1, H2 are used, the supply pressure of the pressure source for directional control is available, a so-called meander circuit is provided for the pressure supply. The pressure line 1 is branched off at a node 14 into a pressure line branch 15a and a pressure line branch 15b. The pressure line branch 15a leads via the recirculation directional seat valves SU provided in the sections H1, H2 to the reservoir line 2, in each case with a pressure line branch 7, 7 'and a reservoir line branch 8, 8'. The other pressure line branch 15b ends, for example, blind. From this pressure line branch 15b branch off the pressure line branches 3, 3 ', to the respective first directional seat valves S1, S1' from. Whenever a magnet M1, M2 in a section H1, H2 or in both sections H1, H2 is brought into the energized state and adjusted a Umlaufwegesitzventil SU in the shut-off, is at all pressure line branches 3, 3 'supply pressure available. In the de-energized state of all provided in the sections H1, H2 magnet, however, the supply pressure is reduced in the reservoir line 2.

The 4 to 6 show a concrete embodiment of such a control device H, for example according to Fig. 1 or Fig. 2 , On a the poppet valves (dash-dotted lines with their longitudinal axes indicated) S1, S2 ', SU, S2, S1' in parallel arrangement side by side containing block 17, z. As steel, a housing part 16 is fixed, on which the two magnets M1, M2 (pot magnets) standing and adjacent to the outer ends of the block 17 (in Fig. 4 ) are mounted. In the housing part 16, the actuating mechanisms 9 (in the Fig. 1 to 3 only indicated schematically) in the form of three actuating levers 20, 26 and 27 housed, which are pivotable, for example, on a common pivot bearing axis 21 angle lever.

In Fig. 4 the circulation directional seat valve SU is at the center while the first and second directional seat valves S1, S2 'are to the left thereof and the first and second directional seat valves S1', S2 are located to the right thereof.

Each angle lever has adjacent to the pivot bearing 21 on an operating part 22, with which he z. B. can act on a linearly movable plunger 18 for actuating the respective Wegesitzventils, and in the region of the free angle lever end a driver part 23, which engages to cooperate with the respective magnet M1, M2 below them.

With the in Fig. 4 shown actuating lever 20, the first and second directional seat valves S1, S2 'simultaneously and via a driver part 23 and the third operating lever 26 are actuated. For this purpose, an armature 25 is provided on each armature plunger 24 on each armature plunger 24 on each plunger side, which extends transversely to the plunger 24 and is aligned with a driver part 23 of an actuating lever 20, 26, 27. The driver 25 is suitably a rotatably mounted roller or a rolling bearing.

The outer operating levers 20, 27 have operating parts 22 for simultaneously operating two directional seat valves and only one driver part 23, while the middle operating lever 26, an actuating part 22 for actuating only the circulation Wegesitzventils SU and two outer driver parts 23 for cooperation with a respective driver 25 each Magnets M1, M2 has. In energized state of in Fig. 4 left magnet M1, the actuating lever 20 and 26 are pivoted, wherein the right driver part 23 of the central operating lever 26 is released from the left driver 25 of the other magnet M2. If the right magnet M2 in Fig. 4 put in energized state, then the actuating lever 27 and 26 are pivoted together, with the left driver part 23 detaches from the driver 25 of the left magnet M1. If both magnets M1, M2 brought into energized state, then the middle operating lever 26 is taken on both driver parts 23 of the drivers 25 of both magnets M1, M2.

The actuation mechanisms 9, 9 'could also be configured differently, provided that it is ensured that each magnet M1 also pivots the middle actuation lever 26 when energized. The circulation path seat valves SU may alternatively be used for relieving a control pressure whose pressure signal actuates a circulation circuit, e.g. in a load pressure control system.

Claims (10)

Control device (H) for controlling the direction of at least one hydraulic motor (Z) from a pressure source (P) in two opposite directions, in particular at working pressures above about 450 bar in a mobile working device (G), with two connected to the hydraulic motor (Z), each containing a first directional seat valve (S1, S1 ') containing working lines (A, B), each of which is connectable via a respective second Wegesitzventil (S2, S2') as a load holding valve with a reservoir (R), and with at least one recirculating Wegesitzventil (SU) circulating circuit (U) between the pressure source (P) and the reservoir (R), wherein for each direction a magnet (M1, M2) is provided with the same time a first and a second directional seat valve (S1, S2 '; S1 ', S2) and the circulation circuit (U) are actuatable for the respective direction, and wherein the recirculation seat valve (SU) is in the passage position, when the respective first and second directional seat valves (S1, S2', S1 ', S2) in the shut-off position n, and vice versa, characterized in that the two magnets (M1, M2) on the actuation side a single, provided in the circulation circuit (U) for both directions divide-way seat valve (SU) share, such that the recirculating directional seat valve (SU ) either alternately by one of the two magnets (M1 or M2) or jointly by both magnets (M1, M2) can be actuated. Control device according to claim 1, characterized in that the circulation directional seat valve (SU) by the respective magnet (M1 or M2) from the passage position in the shut-off position is actuated when the magnet is assigned to him for the one direction associated first and second directional seat valves (S1 , S2 'or S1', S2) are actuated from their shut-off positions into the passage positions. Control device according to claim 1, characterized in that in the de-energized state of both magnets (M1, M2) all first and second directional seat valves (S1, S2 ', S1', S2) in their shut-off positions and the circulation path seat valve (SU) are in the passage position, respectively set by the force of a spring (10). Control device according to at least one of the preceding claims, characterized in that the first and second directional seat valves (S1, S2 ';S1', S2) and the recirculating directional seat valve (SU) have 2/2-way seated valves, one in either one Direction of flow from the pressure source (P) or from the hydraulic motor (Z) to the reservoir or in both directions of flow leak-tight shut-off are. Control device according to at least one of the preceding claims, characterized in that a check valve (12) blocking the pressure source and a throttle (13) are provided between the pressure source (P) and each first directional seat valve (S1, S1 '). Control device according to at least one of the preceding claims, characterized in that the control device (H) at least two parallel to the reservoir (R) connected, from a common pressure source (P) supplied sections (H1, H2) for at least one hydraulic motor comprises, and in that from the pressure source (P) a first pressure line branch (15a) leads to the reservoir (R) only via the recirculating directional seat valves (SU) of the sections (H1, H2) and from the first pressure line branch (15a) upstream or in the upstream direction lying section (H1) branches off a blind second pressure line branch (15b), to each of which the two first Wegesitzventile (S1, S1 ') of the sections (H1, H2) are connected in parallel. Control device according to at least one of the preceding claims, characterized in that in each case the two first and second directional seat valves (S1, S2 ', S1', S2) and the common recirculating directional seat valve (SU) for both directions are parallel to one another in a block (17) are juxtaposed with the recirculating directional seat valve (SU) positioned midway between the outboard positioned first and second directional seat valves (S1, S2 ', S1', S2) such that the two magnets (M1, M2) in FIG Mounted substantially symmetrically outwardly of the center of the block (17) such that at the block (17) there is a middle operating lever (26) associated with the recirculating directional seat valve (SU) and two outer first and second directional seat valves (S1, S2 '; S2) are mounted for a direction associated actuating lever (20, 27), and that each magnet (M1, M2) acts on an outer and the middle operating lever. Control device according to Claim 7, characterized in that the actuating levers (20, 26, 27) are pivotally mounted angle levers which have an actuating part (22) close to the pivot bearing (21) and at least one driver part (23) at the free end Have angle lever end, wherein the middle actuating lever (26) has two outwardly to both magnets (M1, M2) facing driver parts (23). Control device according to claim 8, characterized in that each magnet (M) an anchor tappet (24) with simultaneously on a driver part (23) of an outer actuating lever (20, 27) and a driver part (23) middle actuating lever (26) aligned transverse drivers (25), preferably rotatably mounted rollers, on both anchor tappet sides. Control device according to at least one of the preceding claims, characterized in that the control device (H) is connected to an electric or electronic control (C), with which for each magnet (M1, M2) individually a current or currentless state or for both magnets ( M1, M2) simultaneously energized or de-energized states are adjustable.

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