JPS61201904A - Electricity-hydraulic control apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides a method for connecting an inflow connection, a return connection and two motor connections by means of a longitudinally movable spool provided in a housing. # can be controlled to perform the switching function, the spool can be deflected by longitudinal movement from the neutral position to the first and second operating positions on both sides, and the spool assumes the safety position as an additional switching function. The present invention relates to an electro-hydraulic control device which can be operated against the force of an adjusting spring by means of an electromagnetic reciprocating drive and in which the spool is provided with a control lip corresponding to these switching functions.

[Conventional technology]

Such a control device is disclosed in German Patent No. 2840
831, which has, in addition to the adjustment function, additional safety functions. For this purpose, the longitudinally movable spool has, in addition to a neutral position, the spool in the pilot control stage, an operating position adjacent to it on both sides and a safety position located outside. This safe position, also referred to as fail-safe position, which disconnects the inflow connection a and connects both motor connections to each other or to the outflow, must primarily comply with safety requirements and therefore avoids the passive state of the electromagnetic drive. matches. Now, in this control device, when moved from the neutral position at 1 center to the safe position, the spool of the main control stage, having passed completely through the operating position, moves to the far side, which may be undesirable, and the connected hydraulic pressure This may result in unacceptable operating movements of the motor. Although the safe operation of this control device is sufficient for many use cases, there are also a number of cases in which it is desirable to eliminate such short operating movements.

Furthermore, an electro-hydraulic control device is known from German Patent No. 31 29 594, which operates with two signal inputs. A first signal input of the trowel serves as a control command path, via which translational movements of the input are transmitted directly to a longitudinally movable spool of the control device.

The second signal input consists of an electric rotary drive whose rotary movement is converted into a longitudinal movement via a converter in the control command path, so that both signals are superimposed at the spool'. The spools, which are guided in sleeves fixed to the housing, are operated here by means of control edges which each extend around the piston part and lie in one radial plane. This control device, which is provided for aircraft control, has the disadvantage that it does not have two signal inputs for translational movements. In particular, the disadvantage is that even if the influences from two signal inputs are superimposed on the spool of this control device, the spool can perform only one function. Therefore, the spool itself cannot provide additional functionality.

[Problem that the invention seeks to solve]

The object of the invention is therefore to provide a control device that does not have these disadvantages.

[Means for solving problems]

In order to solve this problem, according to the present invention, the control device has a second electromagnetic reciprocating drive device, the signal output end of this reciprocating drive device is interlocked with the input end of the transmission device, and this transmission device is connected to the reciprocating drive device. converts the longitudinal motion generated by the spool into a rotary motion at its output end, which is connected to the spool so as to prevent relative rotation and to be movable in the longitudinal direction. forming a first control window defined by the spool, the control window being in a first plane extending through the longitudinal axis of the spool, and corresponding to the safety position a second control window belonging to the control window; A longitudinal groove is in a second plane rotated about a longitudinal axis relative to the first plane.

〔Effect of the invention〕

The electro-hydraulic control device according to the invention has the advantage that it allows a particularly high degree of safe operation despite its relatively simple and compact construction. In particular, the control device according to the invention makes it possible to avoid undesired operating movements in the case of safety. The use of an electromagnetic drive for the translation of the second signal input reduces manufacturing costs.

The control device is easily adapted to the different requirements of safety cases. The risk of the moving element becoming stuck is significantly reduced.

Advantageous developments and improvements of the control device according to claim 1 are possible by means of the measures listed in the dependent claims. The embodiment according to claims 2 and 3 is particularly advantageous, as it makes it possible to block the double-acting hydraulic motor in both operating directions in a fail-safe case in a two-stage control device. Furthermore, the embodiment according to patent claim 5 is particularly advantageous, as it makes it possible, in the case of safety, to block only one of the two speed movement directions of a double-acting hydraulic motor. Further advantageous developments emerge from the remaining dependent claims, the description and the drawing.

〔Example〕

Two embodiments of the invention are shown in the drawings and will be explained in detail below.

The electro-hydraulic control device 10 shown in FIG.
A tubular sleeve 12 is housed within 1, within which a spool 13 is supported for longitudinal movement and rotation.

The housing 11 has an inlet connection 14, designated P as usual.
, a first motor connection port 15 indicated by A, and a second motor connection port 16 indicated by B. Furthermore, a first return chamber 17 and a second return chamber 18 are connected to each other and to a return connection 19 .

The sleeve 12 has a diametrically arranged control opening 21 in the area of the motor chamber connected to the first motor connection A, the rectangular shape of which is clearly visible in FIG.
Its two ends simultaneously serve as housing fixing control edges.

The sleeve 12 likewise has a diametrical control opening 22 in the area of the motor chamber connected to the second motor connection B, which control opening has a rectangular shape and serves as a control edge.

The spool 13 has a first piston part 23 in the area of a first control opening 21 and, corresponding to the control opening 21, a first control groove 24 and a second control groove 2 on the diameter of the piston part.
5 is provided. As can be clearly seen in FIG. 2, these control grooves 24 and 25 likewise have a rectangular shape and, together with their respective inner edges, form control edges on the spool 13 that correspond to the control openings 21. Similarly, the control opening 22
A third control groove 27 and a fourth control groove 28 are formed in the second piston portion 26 in this range. First to fourth control grooves 24.25 in both piston parts 23.26
．． 27, 28 and all control openings 21, 22 in the sleeve 12 are in the first surface 29 corresponding to the normal functions. This surface extends through the longitudinal axis of the spool 13 and
In the figure, it corresponds to the plane of the figure.

Spool 13 has a first longitudinal groove 31 diametrically on first piston portion 23 . A second longitudinal groove 32 is likewise provided diametrically in the second piston part 26 . All longitudinal grooves 31, 32 are located in a second surface 33 which likewise extends through the longitudinal axis of the spool 13 and is rotated by a certain angle with respect to the first surface 29, corresponding to the safety feature. These vertical grooves 31 and 32 each have their corresponding return chambers 1
Open towards 7 and 18. As best seen in FIG. 2, the longitudinal grooves 31, 32 are axially configured to such a length that they overlap the corresponding control openings 21 and 22 in the possible positions of the spool 13 when viewed in the axial direction of the spool 13. has been done.

A proportional electromagnet 34 is flange-coupled to the housing 11 to drive the spool 13 for the adjustment function.
It forms a reciprocating drive device. An associated longitudinally movable armature 35 drives the spool 13 in one direction. The spool 13 is loaded in the opposite direction by an adjustment spring 36 via a spring receiver 37.

A transmission 38 is flanged to the end face of the housing 11 remote from the proportional electromagnet 34 and is followed outwardly by a switching electromagnet as a second electromagnetic reciprocating drive 39 . The transmission 38 has an internal thread 42 in the transmission housing 41 into which the threaded portion 4 of the bolt 43 is inserted.
4 is guided coaxially with respect to the spool 13. The bolt 43 has a spring holder 45 at one end and a spring 46
, and at the same time forms the signal input terminal 47 of the transmission 38. The signal input terminal 47 is connected to the armature pin 48
This armature pin inputs the translational reciprocating motion of the switching electromagnet 39 to the transmission 38. If the switching electromagnet 39 is not energized, the spring bearing 45 receiving the spring load is pressed against the stop fixed to the housing, and therefore the bolt 4
3 rotational positions are defined.

The bolt 43 has a narrow protrusion 49 at the other end by cutting both sides.
This lug simultaneously serves as the signal output of the transmission 38. The protrusion 49 enters into the longitudinal slit 52 of the spool 13, so that the signal output end 51 of the transmission 38 is connected to the spool 13 in a manner that prevents relative rotation and allows longitudinal movement.

The control device 10 includes a four-bottom, three-position main control valve 5 with a control connection 54.55 connected to a motor connection 15.16.
It forms three pilot control stages. The main control valve 53 has a vertical spool 56 which is placed in a centered shutoff position 58 by a spring 57. This vertical spool 56 is hydraulically deflectable to both sides into a parallel position 59 and a cross position 11961.

The operation of the electro-hydraulic control device is explained as follows, the first
Reference is made to the figures and the connection diagrams according to FIGS. 2 and 3.

In FIGS. 1 to 3, the control device IO is shown in the same position. The spool 13 is connected to the adjusting spring 36 via its armature 35 by a proportional electromagnet 34 in a known manner.
is displaced in the axial direction by the force of Spool 1
3 assumes the neutral position 63 shown in FIGS. 1-3. At the same time, the switching electromagnet 39 is energized, causing its armature pin 48 to return to the return spring 4.
Assume that the bolt 43 is held in a particular axial position within the transmission housing 1 against a force of 6. Due to the protrusion 49 that fits into the vertical slit 52 of the spool 13,
In its rotational position, the spool 13 is guided so that it can move longitudinally but not rotate relative to it. Spool 13
At this rotational position, the first to fourth control grooves 24
125s 27.28 together with the control openings 21 and 22 in the sleeve 12, as can be seen in particular from FIG.
It is in the first side 29 for common functions. The spool 13 can therefore be brought from its neutral position fi 163 into its operating position 64 or 65 in the usual manner due to its regulating function to drive the main control valve 53. In this normal function, the housing-fixed control openings 21 and 22 together with the respective control grooves 24.25.degree. 27, 28 form a so-called first control window 66.

Now, when a so-called safety case occurs, the switching electromagnet 39
electrical input signal is lost. The switching electromagnet 39 is deenergized and its armature pin 48 is displaced to its initial position by the force of the return spring 46. The longitudinal movement of the switching electromagnet 39 is controlled by the transmission rjII 38 at its signal output end 51.
is converted into a corresponding rotational motion at
9 is turned counterclockwise around the spool 13 about its longitudinal axis so that the longitudinal grooves 31.32 in the second face 33 are now in the plane of the control openings 21.22. In that case, the vertical groove 31.32
together with the control openings 21, 22 fixed to the housing form a second control window 67, which controls the two motor connections 15.
16 to each other and to the return connection 19
8 possible.

In this safe position 28, the pressure at both control connections 54,55 is balanced and the pressure is removed to the tank, so that the main control valve 54.
The three vertical spools 56 are placed in the cut-off position by their springs 57, thereby restraining the connected hydraulic motors in their respective positions.

Due to the complete mechanical decoupling of the actuating drive 35, 39, the safety position 68 starts from the respective position 63, 64 or 65 in the normal function and no intermediate positions are passed through. Undesired operating movements in the main control valve or in the connected hydraulic motor are thereby reliably avoided.

FIG. 4 shows a longitudinal cross-section of a part of a second control device 70 which differs from the control devices according to FIGS. 1 and 2 in the following respects, the same parts having the same reference numerals. - the second control device 70 has a different spool 71, in the piston part 26 of which the previous longitudinal groove 32
Instead, a third vertical groove 72 and a fourth vertical groove 73 are formed. Both of these longitudinal grooves 72 and 73 are the first longitudinal groove 31
, but its axial length is the same as the third and fourth control grooves 27,28.

The operation of the second control device 70 and that of the first control device 1O differ only in that one function can be performed in the case of safety. In the case of safety, the first vertical groove 31;
When the third longitudinal groove 72 and the fourth longitudinal groove 73 are turned from the second surface 33 to the first surface 29, pressure is still established in the control connection 55 of the main control valve 53, and one side function, but the other control connection 54 is always depressurized to the tank, preventing the other function. Such safe operation is often required in pilot-controlled valves, where the hydraulic motor must now be able to operate in a specific direction under specific conditions defined by an electrical signal. This is especially the case with hydraulic control of injection molding machines, where if the closing grate of the clamping cylinder is opened, the tool must still be open on the closing side.

FIG. 5 shows a connection diagram of the second control device according to FIG. Whereas in the safety position 74 one motor connection 15 is always depressurized, a control pressure can be established in the other motor connection 16.

Modifications of the illustrated embodiments are of course possible without departing from the spirit of the invention. Although FIG. 1 shows an advantageous combination of features, it is also possible to use a continuous operating device, for example a second proportional electromagnet, as the second reciprocating drive instead of the switching electromagnet 39. Via the electrically settable rotational position of the spool, a large number of intermediate functions can thereby be made possible. In connection with the fact that the sleeve 12 and the spool 13 cooperate via the control windows 66, 67, a continuously controllable volumetric flow amplification is provided in the control device M1o in continuously adjustable and possible angular positions of the spool. It is done. With a suitable design of the control window, variable pressure amplification can also be achieved in the actuating device which operates continuously as a second reciprocating drive. Furthermore, other modifications are possible without departing from the spirit of the invention.

[Brief explanation of drawings]

1 is a longitudinal sectional view of the first electro-hydraulic control device in a neutral position, FIG. 2 is a view of a part of the first control device according to FIG. 1, viewed in the direction of arrow a, and FIG. is a connection diagram of the first control device, FIG. 4 is a vertical sectional view of a part of the second control device, and FIG.
The figure is a connection diagram of the second control device according to FIG. 4. 10+ 70...control device, 11...housing,
12...Sleeve, 13.71...Spool, 14
...Inflow connection port, 15.16...Motor connection port, 1
9...Return connection port, 21.22...Control opening, 24
．． 25° 27, 28... Control groove, 29... First surface, 31, 32+72, 73... Vertical groove, 33... Second surface, 35.39... Electromagnetic reciprocating drive device , 38...
- Transmission device, 47... Transmission device input end, 48... Reciprocating drive device signal output end, 51... Transmission device output end, 6
3... Neutral position, 64.65... Operating position, 66,
67...Control window, 68.74...Safety position. C1 Jincom-μkoCkoshaku

Claims (1)

Claims: 1. By means of a longitudinally movable spool provided in the housing, the connection of the inflow connection, the return connection and the two motor connections can be controlled to perform a plurality of switching functions; The spool can be deflected by a longitudinal movement from a neutral position to both sides into a first and second operating position, the spool can assume a safe position as an additional switching function, and an electromagnetic reciprocating drive allows the spool to be deflected into a first and second operating position. The control device (10; 70) controls the second electromagnetic reciprocating drive (39) in such a way that the control device (10; 70) can be operated against the forces of The signal output end (48) of this reciprocating drive is coupled to the input end (47) of the transmission (38), which transmits the longitudinal movement generated by the reciprocating drive (39) to its output end. (51), the output end (51) is connected to the spool (13; 71) so as not to rotate relative to it and to be movable in the longitudinal direction, and control grooves (24, 25, 25, 27, 28; 21, 22) are defined in the circumferential direction of the spool (13).
6), the control window being in a first surface (29) extending through the longitudinal axis of the spool (13), and in the safety position (
68) corresponds to the second control window (67), and the vertical grooves (31, 32; 72, 73) belonging to this control window correspond to the first surface (
The second surface (33) rotated around the vertical axis with respect to (29)
) An electro-hydraulic control device, characterized in that it is located within 2. characterized in that both motor connections (15, 16) are connectable to each other and in particular to the return connection (19) via a second control window (67) in the safety position (68), A control device according to claim 1. 3. The connected safe position (68) of the motor connection port (15, 16) passes from each reciprocating position of the spool (13), by rotation about its longitudinal axis, through other positions corresponding in particular to the normal function. The control device according to claim 2, characterized in that it is obtained without any modification. 4 A second control window (67) in the safe position (74) controls the establishment or reduction of pressure at the motor connection (16) via the third longitudinal groove (72) and the fourth longitudinal groove (73). the other motor connection port (15) is connected to the first longitudinal groove (31
2. Control device according to claim 1, characterized in that the pressure is removed to the return connection (19) via the spool (13) irrespective of the axial position of the spool (13). 5. Control device according to claim 1, characterized in that the first reciprocating drive device is a proportional electromagnet (35). 6. Control device according to claim 1, characterized in that the second reciprocating drive is a switching electromagnet (39). 7. The control device according to claim 1, wherein the second reciprocating drive device is a proportional electromagnet. 8 Double reciprocating drive device (35, 39) and transmission device (38)
2. The control device according to claim 1, wherein the control device is provided coaxially with respect to the spool. 9 The transmission (38) is connected to its transmission housing (41).
) has a bolt (43) rotatably supported in an internal thread (42) which is coupled on the one hand to the armature (48) of the second reciprocating drive (39) and on the other hand to the spool 9. The control device according to claim 1 or 8, wherein the control device is connected to (13) so as not to rotate relative to each other and to be movable in a longitudinal direction. 10 Connect the spool (13) to the transmission device (38) in its first
Means for guiding against relative rotation within the plane (29) of
45, 46; 48, 49) are provided, in particular bolts (
The stopper (46) acts as a spring (46) that applies a load to the
10. The control device according to claim 9, characterized in that it is constructed as a lug guide (48) and as a lug guide (49). 11 First and second control windows (66, 67) are connected to the control openings (21, 22) fixed to the housing and the spool (1
3; 71) in the corresponding control grooves (24, 25, 27,
28) and longitudinal grooves (31, 32; 72, 73). 12 Claim characterized in that the spool (13; 71) is part of a pilot control stage of a main control valve (53) with a spool (56) having a spring-centered shutoff position (58) The control device according to scope 1.