JPH0448085B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The invention provides a pressure reduction function pilot-controlled by a control circuit with at least one proportionally variable regulating valve in the inlet conduit to the injection cylinder. plastics injection for controlling the different hydraulic pressures acting on the injection cylinder, having a built-in valve for controlling the pressure medium flow in the inflow conduit, variable control means for influencing the magnitude of the pressure medium flow in the inflow conduit, and a pressure medium source connected to the inflow conduit. The present invention relates to a hydraulic pressure control device for an injection device of a molding machine.

Problems with the Prior Art Such a control device is known from German Patent Application No. 25 23 303, which includes a control circuit for controlling the hydraulic pressure during the phases of injection pressure, packing pressure and backpressure pressure. Only one programmable pressure control valve is provided. A disadvantage of this control device is that for controlling the injection device several main parts are required, which are designed as integrated valves. That is, a pressure reduction cartridge and a displacement detection cartridge are inserted into the inflow conduit leading from the pump conduit to the injection cylinder, and a pressure reduction cartridge is inserted into the outflow conduit leading from the injection cylinder to the tank. In order to control the magnitude of the pressure medium flow into the injection cylinder, an additional throttle valve cartridge is also inserted into the inlet conduit. The large number of main stages in this control device results in considerable construction costs and does not facilitate compact construction of the hydraulic output section. Furthermore, this control device is not suitable for switching from control to regulation.

Furthermore, a hydraulic control device for an injection device of a plastic injection molding machine is known from DE 24 45 158 A1, which operates in particular with a regulating circuit for the parameters of injection speed and injection power. The disadvantage of this control device is that it is designed only for regulating the injection process and is not suitable for simple control. However, the cost is relatively high, especially since this control device uses expensive electro-hydraulic multi-stage servo valves.

Solution to the problem In order to eliminate these disadvantages, according to the invention, the built-in valve is constructed as a three-port valve, the third connection of which is connected to the tank, and the connection to the tank includes a An opening check valve is connected and a variable displacement pump is connected as a source of pressure medium.

Effects of the Invention The hydraulic control device according to the invention thereby allows a reduction in the number of main stages in the hydraulic output section. A single 3-port, 2-position built-in valve can provide the displacement function, pressure regulation function with rapid pressure drop, and backpressure function, which hitherto required several built-in valves. Due to the reduction in main stages, the control device is smaller and therefore cheaper to construct. Furthermore, the 3-port, 2-position built-in valve can also be placed closer to the load, thereby reducing the susceptibility to failures due to long conduits. In particular, however, the control device according to the invention is suitable for different installation stages due to the fact that different pilot control devices can be installed, so that the standard control device can be controlled or regulated without interfering with the hydraulic power output. Suitable for use in injection processes.

Advantageous developments and improvements of the control device according to claim 1 are possible by means of the measures listed in the dependent claims. Claim 2
In the embodiment according to paragraph 1, a standard control device can be used particularly advantageously and simply, by simply using a different pilot control valve in the control circuit for regulating the injection process. Particularly advantageous further configurations emerge from the other dependent claims, in particular the description and the drawing, which promote an energy-saving design of the control device.

Embodiments An embodiment of the invention is shown in the drawings and will be explained in detail below.

FIG. 1 shows a hydraulic control device for controlling an injection device 11 of a plastic injection molding machine, which is not shown in detail. The control device 11 includes an injection cylinder 12 for longitudinal movement of the plasticizing screw 13, as is known in the art.
It has a hydraulic motor 14 for rotating the plasticizing screw.

The injection cylinder 12 is connected via an inlet conduit 15 to the output of an adjustable variable displacement pump 16;
This pump 16 sucks pressure medium from a tank 17. As is known, a regulator 18 is attached to the variable displacement pump 16 to set a predetermined pressure difference Δp ₁ . In order to control the amount of pressure medium flowing into the injection cylinder 12 via the inlet line 15, a proportionally acting throttle valve 19 is inserted in the inlet line downstream of the variable displacement pump 16. This throttle valve 19 divides the inlet conduit 15 into a first part 21 , which is closer to the variable displacement pump 16 , and a second part 22 , which is downstream of the throttle valve 19 .

The second portion 22 similarly includes the variable displacement pump 16
It leads to an inlet connection 23 of a three-way, two-position built-in valve 24 which is inserted into the inlet conduit 15 between the injection cylinder and the injection cylinder. This built-in valve 24 is essentially constructed as a pressure-balanced cartridge with identically sized end faces on its control member 25 and has a first operating connection 26 corresponding to the pressure to be controlled, through which an inlet can flow. A third section 27 of conduit 15 leads to injection cylinder 12 . The second operational connection 28 of the built-in valve 24 connects to the outflow conduit 29
The pressure is relieved in the tank 17 via the outlet conduit 29, which is connected to a check valve 31 which opens towards the tank 17. Furthermore, the built-in valve 24 is connected to the operation connection port 2.
It has a control input port 32 opposite to 6. The control member 25 is additionally loaded on its end face close to the first operational connection 26 by the force of a spring 33 which tends to push the control member 25 into the initial position, in which the inflow connection 23 is blocked, and the first working connection port 26 is connected to the second working connection port 28. Furthermore, the two control edges on the control element 25 are provided with a zero overlap, so that the adjustment function of the integrated valve can be taken into account in particular.

Inflow connection port 23 of 3-port 2-position built-in valve 24
A second inlet conduit 34 is led to the "rapid injection"
During the function, the pressure accumulator 36 is
The injection cylinder can be guided from a second injection cylinder supply device 35 with a. In order to avoid harmful effects from the supply device 35 on the variable displacement pump 16, a second check valve 37 opening towards the built-in valve 24 is provided in parallel with the second inlet conduit 34 into the second part 22.
is inserted.

A first branch line 38 branches off from the first inlet line 15 in the area of the second part 22 and leads to the hydraulic motor 14 and to the tank 17 via a pilot-controlled two-port cartridge 39 . This cartridge 39 is pilot-controlled by a switching valve 41 in conjunction with a shuttle valve 42, and in addition to its directional control function, it can also perform a check valve function for the hydraulic motor 14, so that the plasticizing screw in the reverse direction is 13 rotations are avoided.

Furthermore, a second branch line 43 leads from the second part 22 of the first inlet line 15 via a second switching valve 44 and a third check valve 45 into the annular space 46 of the injection cylinder 12 . In this case, the second switching valve 44 serves as a pilot control valve for a two-port switching cartridge 47 inserted into a return conduit 48 leading from the annular space 46 to the tank 17. The second switching valve 44 has its four connection ports and two positions configured and connected as follows. This valve 44 thus on the one hand controls the pressure relief of the annular space 46 and, on the other hand, can control a small flow of pressure medium into the annular space 46 via the second branch conduit 43 in a degassing function.

From the first inflow conduit 15 other branch conduits 38, 4
3, a third branch conduit 49 leads to the ejection device 51 and a fourth branch conduit 52 leads to the clamping device 53.

A hydraulic control circuit 54 is attached to the 3-port 2-position built-in valve 24, into which a 4-port 2-position pilot control valve 55 is inserted. A first control connection 56 of the control circuit 54 is connected via a first control channel 57 to the inlet connection 23 of the built-in valve 24 . A second control connection 5 in the control circuit 54
8 is connected to the tank 17 via a second control passage 59. Furthermore, the control circuit 54 has a third control connection 16 and a fourth control connection 62, these two control connections forming a third control passage 6.
3 to each other and to a control input port 32 of the built-in valve 24. Now, the pilot control valve 55 is connected in the control circuit 54 as follows. That is, the P connection port is connected to the first control connection port 56, the R connection port is connected to the second control connection port 58, the B connection port is connected to the third control connection port 61, and the A connection port is blocked. There is. A flow restriction valve 64 is connected before the pilot control valve 55 to limit the flow of control pressure medium. In the initial position shown, which is positioned by the spring of the pilot control valve 55, the inflow path for the flow of control pressure medium is therefore blocked, and the control input port 32 of the built-in valve 24 and
The fourth control connection 6 via the third control passage 63
2 is connected to the second control connection 58 and is therefore depressurized.

The variable displacement pump 16 is protected in the main circuit by a pressure limiting valve 65. Variable displacement pump 1
The pilot control circuit 6 is additionally protected by a pressure pilot control valve 66, the pressure being removed via a proportional throttle valve 19 and a throttle 67 on the secondary side. The variable pressure for the ejection device 51 or the mold clamping device 53 is controlled by a proportionally operated and pilot-controlled pressure regulating valve 68 which is connected via a first control line 69 to the pilot control of the variable displacement pump 16. Connected to control circuit. The first control line 19 has a switching valve 71 and is further connected to a second control line 72 leading from a fourth connection 62 of the control circuit 54 to the tank 17 . In the initial position positioned by the spring of the switching valve 71, the pressure regulating valve 68 influences the pressure in the pilot control circuit of the variable displacement pump 16, and when the switching valve 71 is energized, the pressure regulating valve 68
8 can influence the pressure of the control circuit 54 and thus the built-in valve 24 via the control input 32 .

The operation of the control device 10 will be explained as follows with respect to the course of the injection process.

Once the pilot control valve 55 and the switching valve 71 have been brought into their respective operating positions from their initial positions shown in the control circuit 54, the injection process is started in the control device 10. A flow of control pressure medium is then branched off from the first inlet conduit and flows via the first control connection 56 to the pilot control valve 55 , the amount of control pressure medium being determined by the flow restriction valve 64 . In the operating position of the pilot control valve 55, the control pressure medium passes into the third control conduit 63, which branches off on the one hand to the control input 32 of the built-in valve 24 and on the other hand to the second control conduit 7.
2 and the switching valve 71 to the pressure regulating valve 68, and then to the tank 17. The pressure regulating valve 68 therefore determines the pressure at the control input 32 and moves the control member 25 against the force of the spring 33 to effect a connection from the inlet connection 23 to the first working connection 26. . Pressure medium can now flow from the variable displacement pump 16 via the first inlet conduit 15 into the injection cylinder 12 . Because of this pressure medium flow, the three-port, two-position built-in valve 24 operates like a switching valve during the filling phase. If the pressure in the injection cylinder 12 increases following this filling phase, this pressure, together with the force of the spring 33, acts on the end face of the control member 25 that is closer to the first working connection and causes the control input port 32 to
The opposite end face closer to the pressure regulating valve 68
subject to pressure. The pressure adjustment is therefore effected by comparing the forces on the control member 25. By means of the two control edges on the control element 25, pressure medium can be supplied to and discharged from the injection cylinder 12. Therefore, when the injection pressure target value of the pressure regulating valve 68 is reached, the built-in valve 4 operates like a three-port pressure reducing valve to regulate the injection pressure, reducing the pressure from the injection pressure to a lower holding pressure. guaranteed. In the quasi-static phase of injection pressure control, the variable displacement pump 16 is regulated below the pressure value set in the pressure pilot control valve 66, so that the maximum value set there is greater than the respective injection pressure.

The check valve 31 performs a braking function when the plasticizing screw moves to the left due to a stop signal.
The 3-port, 2-position built-in valve 24 moves to the initial position shown. Due to the non-return valve 31, no pressure medium can continue to be sucked in. That is, injection cylinder 1
2 stops. This is particularly important when testing machines, especially when no plasticized material is used.

The annular space 4 of the injection cylinder during the filling stage mentioned above
The pressure medium forced out from 6 flows out via return conduit 48 and switching cartridge 47 into tank 17 . In the "venting" function, a relatively small flow of pressure medium is transferred directly from the first inlet conduit 15 to the second inlet conduit 15.
through the switching valve 44 and non-return valve 45 into the annular space 46 of the injection cylinder 12, and the switching cartridge 47 is only shut off when the plasticizing screw 13 is returned. In this function, built-in valve 2
4 is programmed to approximately zero pressure.

In the "high-speed injection" function, a second pressure medium supply device 35 with a pressure reservoir 36 is also optionally used, so that even higher injection speeds can be obtained at any time.
Even in this "fast injection" function, the built-in valve 24 acts as a three-port pressure reducing valve.

The injection device 11 also performs a "plasticizing" function, for which purpose the plasticizing screw 13 is rotated by a hydraulic motor 14. In this case, the rotational speed of the pressure motor 14 must be kept constant regardless of the particular load pressure. To initiate this function, the switching valve 41 is operated, thereby opening the pilot-controlled cartridge 39 in the first branch conduit 38. In this case, the magnitude of the pressure medium flow to the hydraulic motor 14 is preselected and kept constant by means of the proportional throttle valve 19. This is because, in this throttle valve 19, the pressure gradient Δp ₁ defined by the regulator 18 is always available.
The cartridge 39 in the first branch conduit 38 is
Since it acts as a check valve for the hydraulic motor 14 together with the pilot-controlled shuttle valve 42, reverse rotation of the hydraulic motor is avoided. hydraulic motor 14
is a plasticizing screw 1 via a transmission device (not shown).
3, the plasticizing screw 13 is moved to the right by the plasticized material. In this case, from the injection cylinder to the third conduit section 27, the built-in valve 24
Via the outflow conduit 29 with a check valve 31, the pressure medium is discharged into the tank 17 and into the injection cylinder 1.
The hydraulic pressure in 2 is preloaded to a so-called back pressure so that a homogeneous melt is obtained before the plasticizing screw 13. This back pressure adjustment is incorporated into the valve 24 and the pressure regulating valve 6.
8, with the pilot control valve 55 in its initial position shown, while the switching valve 71
is brought into its working position. Injection cylinder 1
The back pressure of 2 can be adjusted from zero pressure by means of a built-in valve 24.

In the control device 10 for a controlled injection process, the built-in valve 24 can thus perform, in addition to the directional control function, also a pressure regulation function with a rapid pressure drop and a backpressure function. By performing multiple main functions with one built-in valve, the control device 1
0 can be realized with a small control block and a small processing cost. Due to the presence of a central variable displacement pump drive with pressure-flow regulation, the rotational speed of the hydraulic motor 14 remains constant regardless of the load pressure during backpressure regulation by the three-port, two-position built-in valve 24. No additional backpressure valve is therefore necessary. In a controlled injection process, the throttle valve 19 acts as a control means for controlling the magnitude of the volumetric flow into the injection cylinder 12.

The second control device 80 shown in FIG. 2 is designed for a controlled injection process, unlike the control device of FIG. 1 which is controlled for an injection process. The second control device 80 differs from the first control device 10 in the following way, and the same reference numerals are used for the same parts.

The second control device 80 is simply manufactured from a standard control device according to FIG. For this reason, the control circuit 54 for the 3-port, 2-position built-in valve 24 is provided with a 4-port, 4-position adjustment switching valve 81 in place of the pilot control valve 55 that operates to switch. The four connection ports P, R, A, B of this adjustment switching valve 81
are connected to control connections 56, 58 and 61 in the same way as in the control device according to FIG. This valve has a spring-positioned initial position 82 in which inlet connection P is blocked and connection B is depressurized. In three adjacent operating positions 83, 84, 85, connection port B is connected to connection port P, is shut off, and pressure is removed to connection port R. The position of the control member 25 in the built-in valve 24 is now detected by an electro-mechanical displacement detector 86 and fed to the regulating device. Furthermore, the injection cylinder 12 includes an electro-hydraulic pressure detector 87 and an electro-hydraulic pressure detector 87.
A mechanical displacement measuring device 88 is attached to the electrical switch 8
9 can be selectively connected to a regulating circuit.
The setpoint value of the regulating circuit can now be defined at input 91. The fourth connection 62 in the hydraulic control circuit 54 is now switched off, so that the second control line 72 and the associated switching valve 71 as in FIG. 1 are omitted.

The action of the second control device 80 differs from that according to FIG. 1 in that in this device 80 the process parameters of injection speed and injection pressure are adjusted. At that time, 33 ports 2 position built-in valve 24
Due to the zero overlap of its two control edges, it acts as an operating member in the speed and pressure regulating circuit.
The filling process takes place in programmable stages. In this case, the changeover from one stage to another due to the speed and pressure profile can take place as a function of displacement, time, hydraulic pressure or mold internal pressure. An electric switch 89 is provided for switching from the speed regulation circuit to the pressure regulation circuit. In the regulated injection process, therefore, the 4-port 4-position switching valve 24 in the speed regulating circuit is
operates as a control means for determining the volumetric flow rate to the injection cylinder 12 under the action of the displacement detector 88.

Second control device 80 for the regulated injection process
allows an accurate reproduction of the injection process parameters, regardless of the viscosity of the oil and the friction in the injection cylinder 12. As a result, uniform partial quality can be obtained each time.

FIG. 3 shows an attached control circuit 5 having a 3-port 2-position built-in valve 24 and a 4-port 4-position adjustment switching valve.
The functional group of FIG. In the control block 95, the 3-port, 2-position built-in valve 24 is inserted from the flange surface 96 into a corresponding recess (not shown), and the lid 97 to which the built-in valve 24 is attached is inserted.
A displacement detector 86 is provided. A third control passage 63 is led from the control input port 32 in the built-in valve 24 via the lid 97 to the control block 95 and provides a third control connection port 61 and a fourth control connection port 62 in the flange surface 96. is forming. Also visible in the control block 95 is a first control passage 57 exiting from the first inlet conduit 15, which
The control connection port 56 is connected to the control port 56 . Next to that is the second
A control connection port 58 is provided, and a second control passage 59 is provided.
connected to. The first control connection 56 to the third control connection 61 form suitable holes in the flange surface 96 for connecting the connections P, T and B of the regulating switching valve 81. The fourth control connection 62 in the flange surface 96 is closed to the outside. The regulating switching valve 81 itself is provided with an associated proportional electromagnet 81' and a displacement detector 81''.The configuration shown in FIG. 3 of the functional group according to FIG. The second control device 80 is designed in such a way that it can be replaced immediately, i.e. the function group shown in FIG. For this purpose, the adjustment switching valve 81 is replaced by a pilot control valve 55 shown in FIG.
A control conduit 72 leads to the switching valve 71 and thus a connection to the pressure regulating valve 68 is made. In a further controlled injection process, the displacement detector 86 in the three-port, two-position built-in valve 24 can be omitted. This conversion from a controlled standard device to a regulated injection device or vice versa is particularly advantageously carried out without interfering with the hydraulic output part of the control device.

FIG. 4 shows the same functional groups as in FIG. 3, but the regulating switching valve 81 is flanged directly to the built-in valve 24 coaxially with respect to the longitudinal axis of the built-in valve 24. A total of three control passages 5 are provided through the large lid 98 of the built-in valve 24 that makes this possible.
7, 59, 63 are led. These three control passages form three control connections 56, 58, 61 for the 4-port, 4-position adjustable switching valve 81 on a first flange surface 99 of the lid 98, and on a second flange surface 101 on the opposite side. A fourth control connection port 62 is formed in the fourth control connection port 62 . The operation of the function group according to FIG. 4 is the same as that according to FIG.

FIG. 5 shows a third control device 1 which differs from the second control device 80, inter alia in terms of energy saving measures.
05 is shown.

With the second control device 80 according to FIG. 2, energy losses can therefore occur, especially during the filling phase when the pressure in the injection cylinder 12 is still relatively low. During injection, the throttle valve 19 is completely opened,
The pressure regulating valve 68 is set to a value above the injection pressure to be regulated. For automatic adaptation to the load pressure, a third control conduit 106 is provided in the third control device 105, which branches off from the first part 21 of the inlet conduit 15 and includes a restriction 107, a switching valve 108 and a differential pressure valve. 109 leads to the third section 27 of the inflow conduit 15. Differential pressure valve 109 creates a pressure gradient Δp ₂ .

By this measure, a regulated injection process is maintained, and an energy-saving circuit for the filling process is realized with the switching valve 108 and the differential pressure valve 109 for driving the variable displacement pump 16. Switching of the switching valve 108 transfers the control pressure take-off from the secondary side of the proportional throttle valve 19 to the primary side, so that control oil can flow through the third control conduit 106 to the injection cylinder 12. The pressure gradient is thus kept constant via the three-port, two-position built-in valve 24, regardless of the pressure in the injection cylinder 12. This is because the pressure gradient across the control member 25 is equal to the pressure gradient Δp 1 at the regulator 18 of the variable displacement pump 16 and the pressure gradient Δp ₁ at the differential pressure valve 109.
is obtained from the sum of the pressure gradient Δp ₂ at

A part of the fourth control device 110 shown in FIG.
It differs from the third control device 105 according to FIG. 5 as follows, and the same reference numerals are used for corresponding components. The fourth control device 110 has further measures for improving the energy balance and is based on the following considerations.

In the third control device 105 according to FIG. 5, the throttle valve 19 is completely open during the filling process. There, a pressure drop may still occur when the variable displacement pump 16 has its full output available. Under constant pilot control, the inlet connection 23 of the built-in valve 24 connects to the second section 111 of the inlet conduit 15.
This energy loss is reduced when the throttle valve 19 is not connected to the secondary side of the throttle valve 19 as shown in FIG. be able to.

The control device according to FIGS. 2 to 5 for the regulated injection process additionally performs a safety function with its 4/4-position adjustable switching valve. In the absence of a signal, the regulating switching valve 81 removes the pressure at the control input port 32, thereby causing the control member 25 to close to the injection cylinder 12.
no longer allows a subsequent pressure build-up, except for the pressure of .

In the control device according to FIGS. 1, 2 and 5, the control pressure medium supply of the control circuit 54 to the first control connection 56 via the first control channel 57 is further provided in such a manner that the control pressure medium supply flows as shown. It does not take place from the second part 22 of the conduit 15 and therefore from the secondary side of the throttle valve 19, but from the primary side of the throttle valve 19. The first control passage 57 must therefore connect to the first part 21 and not to the second part 22. As a result, the energy balance is improved during injection with a variable displacement pump. This is because a pressure gradient of, for example, 10 bar, produced in any case by the throttle valve 19, is sufficient to open the control member 25 of the 3/2-position valve 24 against the force of the spring 33, which produces a pressure of, for example, only 4 bar. Because it will be. This means is the control device 10, 80, 10
5, in which a 3/2-position built-in valve 24 and a throttle valve 19 are inserted in series with one another in the inlet conduit 15.

Of course, modifications to the illustrated embodiment are possible without departing from the spirit of the invention.

[Brief explanation of the drawing]

Figure 1 shows the first standard configuration for a controlled injection process.
FIG. 2 is a connection diagram of a second control device for the injection process to be regulated; FIG. 3 is a partial longitudinal sectional view of a first configuration of a functional group of the second control device;
FIG. 4 is a partial longitudinal sectional view of the second configuration thereof, and FIGS. 5 and 6 are connection diagrams of parts of the third and fourth control devices of the energy-saving configuration for the regulated injection process. . 10...control device, 11...injection device, 12...
... Injection cylinder, 15 ... Inflow conduit, 16 ... Variable displacement pump, 7 ... Tank, 24 ... 3 port 2 position built-in valve, 23, 26, 28 ... Connection port,
29... Connection path, 31... Check valve, 54... Control circuit, 55... 4 port 2 position pilot control valve.

Claims (1)

Claims: 1. An integrated valve in the inlet conduit to the injection cylinder which can be pilot-controlled and exert a pressure reduction function by a control circuit with at least one proportionally variable regulating valve; With variable control means for influencing the magnitude of the pressure medium flow and a pressure medium source connected to the inlet conduit, the built-in valve is configured as a three-port valve 24, the third connection 28 of which is connected to the tank. 17, and the connection path 29 to the tank 17 connects this tank 17.
For the injection device of a plastic injection molding machine for controlling the different hydraulic pressures acting on the injection cylinder, characterized in that a check valve 31 that opens towards is connected, and a variable displacement pump 16 is connected as the pressure medium source. Hydraulic pressure control device. 2. The 3-port built-in valve 24 is provided in the control block 95, and at least four control connections 56, 58, 61, 62 of the control circuit 54 attached to the control section of the 3-port built-in valve 24 are connected to the flange surfaces 96, 9.
9, 101, and at least one pilot control valve 55, 81 is replaceably provided on the flange surface of the pilot control valve 55, 81. 3 Of the four connection ports 56, 58, 61, 62, the first and 56 are on the inflow side, and the second and 58 are on the tank 17
The control device according to claim 2, wherein the third, 61st and fourth, 62nd ports are connected in parallel to the control input port 32 of the 3-port built-in valve 24. 4. Control device according to claim 2 or 3, characterized in that the four connections 56, 58, 61, 62 are located on only one flange surface 96 of the control block 95. 5 The four connection ports 56, 58, 61, 62 are connected to the two flange surfaces 9 of the lid 98 of the 3-port built-in valve 24.
9,101. The control device according to claim 2 or 3, characterized in that it is located in the following. 6. The direction of the initial position in which the 3-port built-in valve 24 has a control member 25 in which the pressure of the spring 33 and the injection cylinder 12 causes this control member 25 to remove pressure from the injection cylinder 12 to the tank 17 and to block the inflow connection 23. is loaded against the spring 33 by the pressure of the control input port 32 in the direction of the operating position, and in this operating position the third connection port 28 is blocked. A control device according to one of claims 1 to 5. 7 The pilot control valve 55 connects its connection ports P, B,
R is connected to the first to third control connection ports 56, 58, 61 of the control circuit 54, and the fourth control connection port 62 connected to the control input port 32 is connected to the switching valve 71.
can be connected to the pressure regulating valve 68 via a pressure regulating valve 68 , in particular characterized in that this switching valve 71 also controls the connection of the pressure regulating valve 68 to the inflow conduit 15 in the downstream region of the throttle valve 19 . The control device according to one of the ranges 1 to 6. 8. The control member 25 of the 3-port built-in valve 24 is connected to the displacement detector 86, and the first to third control connections 56, 58, 61 of the control circuit 54 are connected to the pilot circuit 90 together with the displacement detector 86. Connection port P of control 4-port 4-position adjustment switching valve 81,
Control device according to one of claims 1 to 6, characterized in that it is connected to R, B. 9 A proportional throttle valve 19 is connected to the inflow conduit 15 upstream of the branch of the branch conduit 38 to the hydraulic motor 14 for the screw 13, and from the secondary side of this throttle valve 19 is connected the control for the regulator 18 of the variable displacement pump 16. 9. Control device according to claim 1, characterized in that pressure is taken off. 10 Third control conduit 1 from the primary side of the throttle valve 19
06 is guided to the injection cylinder 12 via the throttle 107, the switching valve 108, and the differential pressure valve 109, and therefore, the switching valve 108 forms a control pressure extraction path from the secondary side 22 to the primary side 21, and the pressure is adjusted. characterized in that it can be connected to the valve 68;
A control device according to claim 9. 11. The control valve 81 has a spring-positioned initial position 82 in which the control input 32 of the three-port integrated valve 24 is depressurized into the tank 17. Control device according to one of the ranges 1 to 6. 12 Inflow connection port 2 of 3-port 2-position built-in valve 4
12. Control device according to claim 1, characterized in that 3 is connected to a pressure storage tank 36. 13 The regulation circuit 90 is provided with an electro-hydraulic pressure detector 87 connected to the injection cylinder 12 and a displacement detector 88 for detecting the stroke movement of the injection cylinder 12, so that the regulation circuit 90 can vary from pressure regulation to volumetric flow rate. Claims 8 to 12, characterized in that it has a switch 89 for switching to adjustment.
Control device according to one of the clauses. 14. Control device according to one of claims 1 to 7, characterized in that the control means are constructed as a proportional throttle valve 19. 15 3 port 2 position built-in valve 2 as control means
9. Control device according to one of claims 1 to 8, characterized in that 4 is used. 16 The second section 111 of the inlet conduit 15 bypasses the throttle valve 19 and connects the first section 21 to the 3 port 2
Control device according to one of the claims 1 to 6, 8 to 13 and 15, characterized in that the control device is led to a built-in valve (24). 17 Throttle valve 19 and 3 port 2 position built-in valve 24
is connected in series to the inflow conduit 15, the first control connection 56 is connected to the primary side of the throttle valve 19 for supplying control oil to the control circuit 54. Range 1st to 1st
Control device according to one of clauses 5.