AT521266B1 - Closing unit for a molding machine - Google Patents

Abstract

Closing unit for a molding machine with: - a first mold clamping plate (2) which is movable relative to a second mold clamping plate (6), - at least one pull or push rod (3), - at least one closing force mechanism (5), by means of which between the first mold clamping plate (2 ) and the second platen (6), a closing force can be built up, and - at least one of the at least one pull or push rod (3) associated locking device, which is designed to, the at least one pull or push rod (3) with the first platen (2) and / or the second platen (6) and / or the at least one closing force mechanism (5), wherein at least one translation device is provided which is designed to move the closing force mechanism (5) into an actuating movement for the at least one a locking device - preferably mechanically and / or hydraulically Etzen.

Description

Austrian patent office

Description: The present invention relates to a clamping unit for a shaping machine with the features of the preamble of claim 1 and a method for opening or

Closing a clamping unit for a molding machine.

Molding machines can be understood as injection molding machines, injection presses, presses, die casting machines and the like. The state of the art is described below using injection molding machines as an example. However, analogous statements apply generally to molding machines.

Due to the high closing forces that are to be achieved in an injection molding machine, it is often advantageous to separate drives for quick opening and closing movements between a first platen and a second platen (rapid traverse) and for building the clamping force between the first Mold platen and the second platen (power stroke) to provide. It becomes necessary to carry out a lock before the closing force builds up, since the rapid traverse device is not designed to withstand the high closing forces and / or would require a larger amount of oil for the power stroke, which would increase the cycle time. This locking usually takes place via a locking device on the first platen and / or the second platen and / or on the closing force mechanism, the locking device generally being designed as a locking nut. An inner profile on the locking nut interacts with an outer profile of a pull or push rod of the clamping unit and thus prevents movements of the pull or push rod and relative to the locking nut.

From the prior art it is known to provide a drive for a relative movement between the first platen and the second platen and a drive for the actuating movement for opening or closing the locking device (for example a locking nut). In a typical molding cycle of an injection molding machine, the movable platen is first brought up to the fixed platen by the drive until a mold attached to the platen is closed or only opened at a defined distance (e.g. an embossing stroke). Subsequently, a locking is carried out by the locking device in order to shield the rapid traverse device essentially from the forces exerted by the closing force mechanism. After locking, a closing force is applied by the closing force mechanism, which acts on the first mold mounting plate and the second mold mounting plate and presses the mold halves to be fastened to the mold mounting plates together.

The disadvantage of this is that in order to achieve short cycle times, the drive of the locking device and the drive which executes the movement of the closing force mechanism must be precisely coordinated, which in turn provides a point of attack for errors. Another disadvantage of the prior art is that a separate drive is provided for each of the two movements, which is reflected in the costs of the clamping unit (above all in the manufacturing costs).

The object of the invention is to provide a clamping unit for a shaping machine and a method for opening and / or closing such, which allows a simpler and / or associated with less manufacturing effort and / or less error-prone locking compared to the prior art and / or is cheaper and / or allows shorter cycle times.

This object is achieved by a locking unit with the features of claim 1 and a method for opening or closing a locking unit with the features of claim 15.

According to the invention at least one translation device is provided, which

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AT 521 266 B1 2019-12-15 Austrian patent office is designed to convert a movement of the closing force mechanism into an actuation movement for the at least one locking device, preferably mechanically and / or hydraulically.

Accordingly, it is provided that the translation of the movement of the closing force mechanism between the first platen and the second platen is used as the actuating movement of the at least one locking device, which makes it unnecessary to drive the locking device by an additional drive. The translation device also sets the closing force application and the actuating movement of the at least one locking device - preferably automatically - in the desired temporal relationship to one another, as a result of which valuable time can be saved and the cycle times can be reduced.

In other words, a partially or fully automatic locking of the locking device or unlocking from the movement of the closing force mechanism between the first platen and the second platen can be carried out.

According to the invention there is a sequence of movements, the closing force mechanism being activated, preferably a first part of this movement via the transmission device for the locking and ultimately the closing force being applied by this sequence of movements.

[0012] Further advantageous embodiments of the invention are defined in the dependent claims.

It is preferably provided that the at least one locking device has at least one - preferably split - locking nut, it being possible to open and / or close the at least one locking nut by the actuating movement of the at least one locking device.

For locking nuts, there are essentially two predominant designs in the prior art. One uses a split nut, the halves of which are brought together or opened to open or close the pull or push rod (split locking nut). In the other design, both the inner profile and the outer profile do not extend over the entire outer surface of the pull or push rod or the inside of the locking nut. To open it, the locking nut is turned in such a way that there are no threaded areas engaged so that the pull or push rod can be moved. These locking nuts are known as so-called rotating locking nuts. The use of such a rotatable locking nut is also conceivable in a preferred embodiment.

It can be provided that the at least one locking device has a first chamber first piston-cylinder unit for opening and / or closing the at least one locking device - preferably with a reset element or reset mechanism, particularly preferably a spring return. Furthermore, it can be provided that the transmission device has a second piston-cylinder unit, wherein a volume of a second chamber of the second piston-cylinder unit of the transmission device can be changed by the movement to apply closing force. It is particularly preferably provided that the first chamber of the first piston-cylinder unit of the locking device and the second chamber of the second piston-cylinder unit of the transmission device are hydraulically connected or connectable. In such an exemplary embodiment, the change in a second chamber of the second piston-cylinder unit of the transmission device can thus have a direct influence on the first chamber of the first piston-cylinder unit of the locking device.

It can be provided that the first piston-cylinder unit of the locking device and the second piston-cylinder unit of the transmission device are connected or connectable via a hydraulic unit. Such a hydraulic unit can

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AT 521 266 B1 2019-12-15 Austrian patent office, for example, have at least one controllable or regulable valve and / or a pressure ratio. A controllable or regulatable valve can thus be provided in order to hydraulically connect or separate the first piston-cylinder unit and the second piston-cylinder unit. Especially when setting a mold height for a molding tool, it may be necessary that the closing mechanism can be moved for adjustment without always automatically locking the pull or push rod. Furthermore, pressure translation can be provided since it is not always necessary to apply the same pressure to the locking device (more precisely the first piston-cylinder unit) that is generated by the second piston-cylinder unit of the translation device.

The closing force mechanism can include, for example, a hydraulic pressure cushion (piston-cylinder unit) or at least one spindle drive for the application of closing force.

In a further exemplary embodiment it can be provided that the translation device has a first surface and a second surface interacting with the first surface, the first surface and / or the second surface being at a positive angle to a direction of travel of the second platen relative to has first platen. For example, it can be provided that an inclined surface of the transmission device converts a direction of movement of the closing force mechanism into an actuating movement of the locking device that is not parallel to the direction of movement of the closing force mechanism. A positive angle is to be understood as a non-zero angle.

Alternatively or additionally, it can be provided that the translation device has at least one guide element guided in a guide link, the direction of movement of the closing force mechanism being able to be converted into the actuating movement for the at least one locking device by the geometric configuration of the guide link. The at least one guide link can be designed on the at least one locking nut and can preferably be formed in one piece with it. However, it is also conceivable that the at least one guide element is designed on the at least one locking nut and is preferably formed in one piece with it. For example, a guide pin can be used as the guide element. Accordingly, it can be provided that a guide link is provided on each half of a divided locking nut and that the locking nut is opened or closed by guiding the guide element in the guide link.

However, it can also be provided that such an embodiment is used in a rotatable locking nut and by guiding the guide element in the guide link, the linear direction of movement of the locking mechanism is converted into a rotary movement, so that the locking nut when opening or closing with their thread into or off a thread of the pull or push rod.

It can also be provided that the translation device has at least one lever mechanism for converting the direction of movement of the closing mechanism into the actuating movement of the at least one locking device.

Preferably, at least one reset element for opening and / or closing the at least one locking device is provided. This restoring element can have, for example, a spring element, at least one spring element loading the at least one locking device being provided such that opening and / or closing of the at least one locking device can be driven by relieving the pressure on the at least one spring element.

According to such an embodiment variant with at least one guide element, it can be provided that only one movement has to be carried out by the translation device (opening or closing the locking nut)

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AT 521 266 B1 2019-12-15 Austrian patent office and that this movement of the transmission device prestresses the at least one spring element. This bias can accordingly be used in the subsequent closing or opening of the at least one locking device in order to drive the movement.

It can be provided that at least one rapid traverse device is provided for driving a relative movement between the first platen and the second platen. Possible embodiments are, for example, a hydraulic drive, a mechanical drive or, for example, a drive by means of a ball screw. Furthermore, it can be provided that the at least one rapid traverse device is designed by at least one hydraulic linear drive - preferably a hydraulic piston-cylinder unit - and / or at least one spindle drive.

Protection is also sought after for a molding machine with a clamping unit according to the invention.

With regard to the method according to the invention, the object of the invention is achieved by converting a direction of movement of the closing mechanism, by means of which a closing force is built up between a first platen and a second platen, into an actuating movement for at least one locking device, with a pulling or Push rod is locked or unlocked by the actuating movement with respect to a first platen and / or a second platen and / or at least one closing force mechanism.

[0027] Further advantages and details of the invention result from the figures and the associated description of the figures. Show:

Figure 1 Figure 2 an embodiment of a locking unit according to the invention, a first embodiment of the locking unit according to the invention with an open locking nut, Figure 3 the first embodiment of the locking unit according to the invention with a closed locking nut, Fig. 4 a second embodiment of the locking unit according to the invention with an opened locking nut, Fig. 5 the second embodiment of the locking unit according to the invention with a closed locking nut, Figure 6 A third embodiment of the locking unit according to the invention with an open locking nut, Fig. 7 the third embodiment of the locking unit according to the invention with a closed locking nut, Fig. 8 A fourth embodiment of the locking unit according to the invention with an open locking nut, Fig. 9 the fourth embodiment of the locking unit according to the invention with a closed locking nut, Fig. 10 a fifth embodiment of the locking unit according to the invention with an open locking nut and Figure 11 the fifth embodiment of the locking unit according to the invention with a closed locking nut.

Fig. 1 shows a general overview of an embodiment of a clamping unit 1 according to the invention in a two-plate construction, wherein a first mold mounting plate 2 is movable relative to a second mold mounting plate 6 by a rapid traverse device 16.

On the second platen 6 there are four pull or push rods 3 bewe4 / 21

AT 521 266 B1 2019-12-15 Austrian patent office secured with a key (whereby by projecting the view shown only two train or

Push rods 3 can be seen).

With a closing movement, the first platen 2 can now be brought up to the second platen 6 by the rapid traverse device 16 and the pull or push rod 3 can be locked by the locking device 15. The manner in which the locking device 15 is locked is described in more detail in the following exemplary embodiments (and their figures).

2 shows a first exemplary embodiment of the clamping unit 1 according to the invention for a shaping machine with a locking nut 4 in the open state in a partially sectioned view. In this embodiment, the locking nut 4 is made in two parts and has an upper half shell 4.1 and a lower half shell

4.2 on, which are movable radially to the pull or push rod 3 to each other. The locking nut 4 is opened or closed by means of a first piston-cylinder unit 7 which has a first chamber 7.2 and a spring return 7.1 for opening the locking nut 4.

If a movement of the closing force mechanism 5 is now carried out, the piston 8.1 of the second piston-cylinder unit 8 is moved to the left (in the direction of the locking nut 4) by supplying fluid into the chamber 8.4 of the second piston-cylinder unit 8 , whereby the volume of the second chamber 8.3 of the second piston-cylinder unit 8 decreases. This volume of the second chamber 8.3 is formed by a cavity between the piston 8.1 and the cover 8.2 of the second piston-cylinder unit 8. When the volume of the second chamber 8.3 of the second piston-cylinder unit 8 is reduced, a fluid which is present in this second chamber 8.3 is ejected (hydraulic fluid such as oil in this exemplary embodiment).

The ejected fluid from the chamber 8.3 is pushed via a hydraulic line 9, past a first controllable or controllable valve 10, into the first chamber 7.2 of the first piston-cylinder unit 7, whereby the first piston-cylinder unit 7 extends and the locking nut 4 closes. As a result, the grooves arranged on the locking nut 4 engage in the grooves provided on the pull or push rod 3 and the pull or push rod 3 is locked with the closing force mechanism 5.

When the locking nut 4 is closed by the first piston-cylinder unit 7, by increasing the volume of the chamber 7.2, the spring return 7.1 is biased, which takes over the drive of this unlocking movement when the locking nut 4 is opened. The spring return 7.1 is located in a fourth chamber 7.4 of the first piston-cylinder unit 7. After locking, the valve 10 can be closed if necessary.

In this embodiment, it is further provided that the second piston-cylinder unit 8 takes over the function of the closing force mechanism. Thus, when the locking nut 4 is locked, hydraulic fluid can be supplied from a tank 12 via the second controlled or regulated valve 11, which is switched to flow to apply closing force, into a third chamber 8.4 of the second pistons by means of a pump 13 which is driven by a motor 14 -Cylinder unit 8 are promoted, whereby the piston 8.1 of the second piston-cylinder unit 8 is moved to the left - in the direction of the locking nut 4. However, since the locking nut 4 is now connected to the pull or push rod 3, this force is passed on to the pull or push rod 3, whereby in this exemplary embodiment the pull or push rod 3 is to be regarded as a pull rod which, due to this force application, has a closing force between transmits first platen 2 and second platen 6.

After completion of the injection cycle, the second controlled or regulated valve 11 can now be switched to a discharge position and the prevailing pressure of the chamber 8.4 of the second piston-cylinder unit 8 can be reduced in the tank 12 until the

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AT 521 266 B1 2019-12-15 Austrian patent office

Hydraulic fluid in the chamber 8.4 only has the ambient pressure. The second controllable or regulatable valve 11 is then moved to a blocking position and the first valve 10 is opened if necessary. The spring return 7.1 of the first piston-cylinder unit 7 can now open the locking nut 4 by returning hydraulic fluid from the chamber 7.2 of the first piston-cylinder unit 7 via the hydraulic line 9 through the controllable or regulatable valve 10 the chamber 8.3 of the second piston-cylinder unit 8 conveys, which in turn moves the piston 8.1 of the second piston-cylinder unit 8 to the right - in the direction of the second platen 6.

The embodiment of FIG. 2 is shown in a closed state of the locking nut 4 in FIG. 3. Accordingly, it can be seen that the locking of the locking nut 4 is carried out automatically, so to speak, by the movement of the closing force mechanism.

The embodiment of Figures 4 and 5 is similar to that of Figures 2 and 3. In contrast to Figures 2 and 3, the embodiment of Figures 4 and 5 is designed as a closed hydraulic circuit.

A hydraulic unit 18 takes over the function of the first controllable or regulatable valve 10, the second controllable or regulatable valve 11 and the control of the closing force mechanism 5. In FIG. 4 the embodiment with an opened locking nut 4 is again shown and 5 shows the same exemplary embodiment with a closed locking nut 4.

As in the embodiment of Figures 2 and 3, again when the piston

8.1 of the second piston-cylinder unit 8 is displaced, a hydraulic fluid is pushed out of the second chamber 8.3, which via the hydraulic line 9 enters the chamber 7.2 of the first piston-cylinder unit 7 for closing the locking nut 4. Furthermore, a pressure transmission can be provided in the hydraulic unit 18, which can be designed to reduce or increase the pressure of the hydraulic fluid generated by pushing the hydraulic fluid out of the chamber 8.3, since it is seldom exactly the pressure required to lock the locking nut 4 becomes like that which is present when the hydraulic fluid is pushed out of the second chamber 8.3. Furthermore, volume compensation can be carried out by means of the pressure ratio, since the volume required in the chamber 7.2 of the first piston-cylinder unit 7 also rarely matches the volume pushed out of the chamber 8.3 of the second piston-cylinder unit 8. Furthermore, this pressure translation can be used to translate a pressure generated by the pump 13, which is subsequently required when the closing force is built up.

Another advantage of such a central hydraulic unit 18 may be that it is not only used for exactly one locking device 15 and exactly one closing force mechanism 5, as shown in the exemplary embodiment in FIGS. 4 and 5, but for several.

Figures 6 and 7 show a further embodiment of a locking unit 1 according to the invention, wherein again Fig. 6 shows the embodiment with an open locking nut 4 and in Fig. 7 the embodiment is shown with a locked locking nut 4.

It can be seen here that the first piston-cylinder unit 7 has a first chamber 7.2, hydraulic fluid in turn being able to be fed into the first chamber 7.2 of the first piston-cylinder unit 7 in order to move the piston 7.3 of the first piston-cylinder Unit 7 (to the left towards locking nut 4). In other words, a movement of the closing force mechanism 5 is started by the supply of hydraulic fluid into the first chamber 7.2. By displacing the piston 7.3 of the first piston-cylinder unit 7, a first surface 22 of the piston 7.3 is brought up to a second surface 23 of the upper half-shell 4.1 of the locking nut 4, the first surface 22 then interacting with the second surface 23.

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AT 521 266 B1 2019-12-15 Austrian Patent Office [0055] In this exemplary embodiment, the first chamber 7.2 of the first piston-cylinder unit is embodied in the first platen 2.

When the first surface 22 of the piston 7.3 abuts the second surface 23 of the locking nut 4, the upper half 4.1 of the locking nut 4 is shifted downward, since the first surface 22 and the second surface 23 are at an angle α to the direction of the Movement of the locking mechanism 5 are formed. Through this angle α, which the first surface 22 and the second surface 23 have, the movement of the locking mechanism 5 can be converted into an actuating movement of the locking nut 4 and the locking nut 4 can be set into a locked position (as shown in FIG. 7).

For the subsequent unlocking of the locking nut 4, two spring elements 21 are provided in this exemplary embodiment, which are put under bias by the locking and drive the unlocking movement of the locking nut 4 by the bias when unlocking. Furthermore, in this exemplary embodiment, a mold height adjustment device 20 can be seen, which is designed to adapt the locking device to different mold heights of a molding tool. The mold height adjustment device 20 is designed as a further piston-cylinder unit, which is hydraulically adjustable. The mold height adjustment device 20, which is designed as a hydraulic piston-cylinder unit in this exemplary embodiment, could of course also be implemented by similar drives, such as a spindle drive or the like.

Figures 8 and 9 show an alternative embodiment of a clamping unit 1 according to the invention. Again, a piston 7.3 of a first piston-cylinder unit 7 can be moved in the direction of a locking nut 4 by hydraulic fluid of a first chamber

7.2 is supplied. FIG. 8 shows an open state of the locking nut 4 and FIG. 9 shows a closed state of the locking nut 4, the locking nut 4 again being designed as a split locking nut.

If the piston 7.3 is now moved in the direction of the locking nut 4, a lever mechanism 24 is folded over, which converts the movement of the locking mechanism 5 into an actuating movement of the locking nut 4 by this folding movement. As already shown in the previous figures, two spring elements 21 are also provided here for opening the locking nut 4. Furthermore, a mold height adjustment device 20 is shown in order to adapt the locking nut 4 to different mold heights.

Figures 10 and 11 show an embodiment of a locking unit 1 according to the invention using a guide element and a guide link 26 as a translation device. Again, a piston 7.3 of a second piston-cylinder unit 7 is used to generate the movement of the closing force mechanism. This translation device contains guide pins 25 which are guided in a guide link 26. The guide links 26 are incorporated into the upper half-shell 4.1 and the lower half-shell 4.2 of the locking nut 4. By moving the locking nut 4, the guide link 26 can now be moved relative to the guide pin 25, a radial displacement of the upper half-shell 4.1 and the lower half-shell 4.2 being carried out with a relative movement. If a rotatable locking nut 4 is provided, the movement through the guide link 26 and the guide bolt 25 could also be converted into a rotational movement for opening and / or closing this rotatable locking nut 4.

10 shows an open state of the locking nut 4 and FIG. 11 shows a closed state of the locking nut 4. Furthermore, as in the previous exemplary embodiments, two spring elements 21 are provided which support the opening movement of the locking nut 4.

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AT 521 266 B1 2019-12-15 Austrian patent office

LIST OF REFERENCE NUMBERS:

Closing unit first platen

Drawbar or push rod

locking nut

4.1 upper half-shell of the locking nut

4.2 lower half-shell of the locking nut

Closing force mechanism second platen first piston-cylinder unit

7.1 Spring return of the first piston-cylinder unit

7.2 first chamber of the first piston-cylinder unit

7.3 Piston of the first piston-cylinder unit

7.4 fourth chamber of the first piston-cylinder unit, second piston-cylinder unit

8.1 Piston the second piston-cylinder unit

8.2 Cover of the second piston-cylinder unit

8.3 second chamber of the second piston-cylinder unit

8.4 third chamber of the second piston-cylinder unit

Hydraulic line first controllable or regulatable valve second controllable or regulatable valve

tank

pump

engine

locking device

Eilgangvorrichtung

Hydraulic unit

Formhöhenverstellvorrichtung

Spring element first surface second surface

lever mechanism

guide pins

Guide link α angle

Claims (15)

1. Closing unit for a molding machine with: - a first mold mounting plate (2) movable relative to a second mold mounting plate (6), - at least one pull or push rod (3), - At least one closing force mechanism (5), by means of which a closing force can be built up between the first platen (2) and the second platen (6), and - At least one of the at least one pull or push rod (3) associated locking device, which is designed to the at least one pull or push rod (3) with the first platen (2) and / or the second platen (6) and / or to lock the at least one closing force mechanism (5), characterized in that at least one translation device is provided which is designed to convert a movement of the closing force mechanism (5) into an actuating movement for the at least one locking device - preferably mechanically and / or hydraulically. 2. Locking unit according to claim 1, characterized in that the at least one locking device has at least one - preferably split - locking nut (4), wherein opening and / or closing of the at least one locking nut (4) can be carried out by the actuating movement of the at least one locking device , 3. Locking unit according to one of the preceding claims, characterized in that the at least one locking device has a first chamber (7.2) having the first piston-cylinder unit (7) for opening and / or closing the at least one locking device - preferably with a spring return (7.1 ) - having. 4. Closing unit according to one of the preceding claims, characterized in that the translation device has a second piston-cylinder unit (8), wherein a volume of a second chamber (8.3) of the second piston-cylinder unit (8) of the translation device by Movement of the closing force mechanism (5) is changeable. 5. Closing unit according to claim 3 and 4, characterized in that the first chamber (7.2) of the first piston-cylinder unit (7) of the locking device and the second chamber (8.3) of the second piston-cylinder unit (8) of the transmission device are hydraulically connected or connectable. 6. Closing unit according to claim 5, characterized in that the first piston-cylinder unit (7) of the locking device and the second piston-cylinder unit (8) of the transmission device are connected or connectable via a hydraulic unit (18). 7. Closing unit according to one of the preceding claims, characterized in that the translation device has a first surface (22) and a second surface (23) interacting with the first surface (22), the first surface (22) and / or the second Surface (23) have a positive angle (a) to a direction of travel of the second platen (6) relative to the first platen (2). 8. Locking unit according to one of the preceding claims, characterized in that the translation device has at least one guide element guided in a guide link (26), the movement of the closing force mechanism (5) in the actuating movement for the at least by the geometric configuration of the guide link (26) a locking device can be implemented. 9.21 AT 521 266 B1 2019-12-15 Austrian patent office 9. Closing unit according to claim 8, characterized in that the at least one guide link (26) is designed on the at least one locking device and is preferably formed in one piece therewith. 10. Closing unit according to claim 8 or 9, characterized in that the at least one guide element is designed as a guide pin (25). 11. Closing unit according to one of the preceding claims, characterized in that the translation device has at least one lever mechanism (24) for converting the movement of the closing force mechanism (5) into the actuating movement of the at least one locking device. 12. Closing unit according to one of the preceding claims, characterized in that a return element for opening and / or closing the at least one locking device is provided. 13. Closing unit according to claim 12, characterized in that the restoring element has at least one spring element (21) which loads the at least one locking device such that opening and / or closing of the at least one locking device can be driven by relieving the at least one spring element (21) , 14. Molding machine with at least one clamping unit (1) according to one of the preceding claims. 15. A method for opening or closing a closing unit (1) for a molding machine, preferably according to one of claims 1 to 13, characterized in that a movement of the closing force mechanism (5), by means of which closing force mechanism (5) between a first platen (2) and a second mold clamping plate (6) is built up with a closing force which is converted into an actuating movement for at least one locking device, a pull or push rod (3) being actuated with respect to a first mold clamping plate (2) and / or a second mold clamping plate (6) and / or at least one closing force mechanism (5) is locked or unlocked.