AT510305B1 - CONTROL DEVICE FOR AN INJECTION MOLDING MACHINE - Google Patents

Abstract

Injection molding machine with a first stop element (35) moved by a drive unit and a drive element (2) operatively connected to the first stop element (35) and with a second stop element (36), the first stop element (35) ejector pins (7) and one first stop surface (30), which are preferably translationally movable by the drive unit (2) and for the Auswerfervorgang the first stop element in the course of the injection molding on the second stop element (36) which is arranged in or on the injection mold, and with a control device (31), wherein a detection device (11) is provided, from which the force with which the first stop element (35) impinges on the second stop element (36) measurable and fed via a transmission device (33) of the control device (31) is.

Description

Tire CKS AT510 305B1 2014-03-15

Description: The invention relates to an injection molding machine having a first stop element moved by a drive unit and a drive element operatively connected to the first stop element and having a second stop element, the first stop element comprising ejector pins and a first stop surface which is preferably translationally driven by the drive unit are movable and for the Auswerfervorgang the first stop element in the course of the injection molding process on the second stop element, which is arranged in or on the injection mold, bounces and with a control device.

In injection molding machines, it is already necessary for the sake of a short production cycle, to let various, movably mounted components of the injection molding machine in the course of an injection molding deliberately collide, instead of slowly and leisurely approximate the corresponding components. As an example, the two mold halves of an injection mold called together form the cavity. These mold halves must be closed for the injection molding process. In this case, the one mold half as the first stop element impact on the other mold half as a second stop element.

Another example is the Auswerfervorrichtung of injection molding machines. Such Auswerfervorrichtungen serve the ejection of semi-solidified or fully solidified injection molded parts from the cavity, which is formed by the two mold halves of an injection mold, which is also known as injection molding. For this purpose, movably mounted ejector pins are arranged in the region of the injection mold, with which the injection molded parts can be ejected from the cavity of the injection mold. The ejector pins are connected to an ejector and are moved by a drive unit of the ejector. Such ejector pins are known in the art.

However, certain injection molded parts can only be ejected from the ejector pins when the moving during the ejector drive elements of the ejector and the associated and therefore also moving ejector stop abruptly. As a result of this abrupt movement stop and the associated acceleration, the injection molded parts can fall out of the injection mold or of the ejector pins.

This abrupt stopping is generally made possible by bouncing one of the moving parts of the ejection device and the ejector pins connected thereto onto a stop surface of a stationary component of the injection molding machine at a certain speed. In particular, in electrically operated injection molding machines, the drive unit of the ejector usually has a servo motor and other rotating parts, such as a spindle, various pulleys u. Like., Due to their high mass and the associated high moment of inertia occurring in the course of an abrupt stop by an impact on a stationary component and the associated start in a mechanical end position large forces on the components in the power flow, ie between the drive unit and exercise the ejector pins. In particular, the spindle of a spindle drive and the bearings of the movably mounted parts of the drive unit are sensitive to such loads and can be destroyed by a hard impact or at least damaged. This concerns in particular the ball raceways of the bearings and the spindle. On the other hand, a start or a collision at a lower speed or the execution of too early or too strong a braking operation of the moving parts of the ejector before impact and the associated achievement of the mechanical end position means that certain injection molded parts are not removed from the injection mold, which leads to an extension of the cycle time, since these injection-molded parts must be removed dog-like.

U m damage to the drive unit, in particular the spindle of a spindle drive to avoid, are provided Sollverläufe for the moving stop element, on the one hand the speed at which the movably mounted stop element is moved 1/26

On the other hand, that point along the path of the moving stop element are given, and on which the drive unit stops driving the movably mounted stop element or a braking operation for delaying the first stop element and / or a drive element operatively connected to the stop element, which is supplied with energy by the drive unit and from which the first stop element is moved, for example by braking the stop element and / or the drive element by means of a brake device or an electric motor, which supplies the necessary energy for moving the stop element, is switched off or disconnected from the drive unit. In addition, the end position of the stop element may be predetermined, at which the stop element should come to a stop. In the case of an active deceleration, the nominal course can have so-called deceleration ramps, by means of which it is specified at which rate the moving stop element is decelerated.

The setting of the desired course, in particular the height of the maximum speed of the moving stop member and the time at which the driving is stopped or a braking operation is initiated, designed in general very difficult and also depends heavily on the appropriate conditions, such as the type of injection molded parts to be produced. Generally occur in such an impact, as it results, for example, for ejecting the injection molded parts, enormously high forces. If the target curves for the moving stop element are set incorrectly, this can lead to the destruction of the stop element and the drive unit connected to it, because, on the one hand, the impact occurs at too high a speed, e.g. because the target position at which the first stop element should have come to a halt, or on the other hand, the drive unit still attempts to drive the movably mounted stop element, although the mechanical system has already been reached by the impact on the second stop element.

An ejector device as described above is shown in JP 2003-039504, which comprises a device for calibrating the stroke of the ejector pins of an injection molding machine. If this stroke is set incorrectly, a damping spring is compressed, wherein the compression is detected by a sensor, whereupon the injection molding machine is stopped. As a result, repeated, too hard stops can be avoided only insofar as the stroke of the ejector pins is readjusted. This involves laborious adjustments and long production cycles.

The object of the present invention is to avoid these disadvantages and to provide a device available to provide a connected with a faulty impact destruction of components of the ejector of an injection molding machine.

This is made possible by an injection molding machine with the features of claim 1.

By a detection device according to the invention is provided, with which the force occurring upon impact of driven by a drive unit first stop element on a second stop member force or a related force with this force can be measured, it is possible to have a parameter available provide, by means of which the control device can initiate further processes of the injection molding machine with respect to the movement of the first stop element and / or the drive element. This parameter serves as a decision criterion and can be fed to the control device with a transmission device. For example, the control device may decide to initiate or amplify a braking operation for the first stop element and / or drive element operatively connected to the stop element, or to yield or yield the second stop element as a result of the impact, or to modify future movement of the first stop element. The operative connection between the drive element and the first stop element allows the first stop element to be driven by the drive element and may be e.g. be releasable and / or a relative movement 2/26

asterreidisÄs pitwiarot AT510 305B1 2014-03-15 allow. The transmission device consists of known electronic components and signal transmission means.

The detection device can measure the force occurring during the impact directly or indirectly. The measured variable may be an instantaneous value or a value averaged over a short period of time or a maximum value occurring in this short period of time.

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

In an embodiment of the invention, the control device comprises means for comparing the value measured by the detection device with a reference value, e.g. can represent a maximum force. These means include known electronic components.

Now exceeds the value measured by the detection device, the reference value, for example, because the speed at which the first stop element is impacted on the second stop element, has been too high or the braking process for the first stop element has been initiated too late or with a has occurred at low deceleration rate, controls the control device to a braking device to initiate braking or deceleration of the first stop element and / or standing in operative connection with the first stop element drive element. For this purpose, a further transmission device is provided, by means of which the control device can transmit a corresponding signal to the braking device.

The further transmission device consists of known electronic components and signal transmission means.

It can also be provided that the detection device, the force acting during the bouncing force by means of a computing unit comprising suitable electronic components, such. a processor, integrate and compare with the reference value of an integrated force. This is relevant if, for example, as a result of a malfunction, the drive unit attempts to drive the first stop element even if it has already impacted on the second stop element and has reached a mechanical end position. In this case, the destructive effect for the components of the injection molding machine is not necessarily achieved by a single force peak, but by an over too long time force. As a result, for example, the motor of the drive unit can be destroyed.

The delay of the moving first stop element can be done by an active braking with a suitable braking device. These include hydraulic or pneumatic brake elements but also devices with which the speed of an electric motor can be reduced or the direction of rotation can be reversed.

But it is also possible that the braking device only serves to ensure that an active driving of the first stop element is terminated, whereupon this decelerates by itself in consequence of the acting friction. In this case, the braking device may comprise a device with which the power supply is interrupted by the engine or the engine is decoupled from the drive unit. It is also possible that the braking device has passive brake elements for braking the first stop element.

The necessary electrical and electronic components for the measurement by means of the detection device, as well as for comparison with the reference value are known as well as the means for forwarding the control signals to the braking device per se in the prior art.

In one embodiment of the invention, the control device on an emergency stop device, preferably in the form of a circuit breaker, with an immediate shutdown of the drive unit can be done.

In one embodiment of the invention, the detection device has a vibration measuring device, with the vibrations of the first and / or second Anschlagele- 3/26 Mentes can be measured, since the impact of the first stop element on the second stop element, the first and the second Stop element are vibrated. The amplitude of these vibrations is a measure of the force generated during the impact. Additionally or alternatively, the detection device may include a strain gauge, e.g. a strain gauge, for measuring a resulting from the impact of the first on the second stop element deformation of the first and / or second stop element can be measured. This deformation is mostly reversible since the first stopper member and the second stopper member are made of an at least partially elastic material, e.g. Metal exist. Such deformation is also a measure of the impact force of the impact of the first stop element on the second stop element. In addition, proximity sensors such as inductive sensors, tactile sensors, and the like are used as the vibration measuring device or the deformation measuring device.

The detection device may also include a sensor with which the recorded by an electric motor power or a change in the engine speed can be measured, which can also serve as a measure of the impact force. In the case of a hydraulic or pneumatic injection molding machine, the detection device may comprise a sensor for the pressure in the hydraulic or pneumatic system, which may also serve as a measure of the impact force.

In one embodiment of the invention, the detection device has a measuring device for measuring a damping force, which results from the damping of the impact of the first stop element on the second stop element. If this damping by means of a spring, this measuring device can be designed as a measurement of the spring force, for example by the compression of the spring is measured. In this case, the extent of the compression and / or the speed at which the spring is compressed can be measured. Such measuring devices are e.g. given by inductive sensors, light barrier sensors, etc. It may be provided that only the standing with the stop element in operative connection drive element is damped after the first is impacted on the second stop element.

In a further embodiment, the control device has an electronic memory, are stored in the target curves for the movement of the first stop element. These nominal curves include the relevant parameters for the movement of the stop element, such as the acceleration, the maximum speed, the location and time at which a braking operation is initiated and optionally the rate at which the stop element is delayed.

According to the invention, it is now provided to modify the setpoint curves as a function of the measured variable determined by the detection device and store them in a modified form in the electronic memory for future injection molding processes. Exceeds the measured value measured by the detection device, the reference value, for example, because the wrong setting course is present or the settings of the injection molding machine are incorrect and thus the impact of the first to the second stop element is too strong, the control device can correct this for other processes and the desired course change accordingly, whereby a repeated erroneous impact of the first is prevented to the second stop element. The modification may for example be given by a reduction of the maximum speed of the first stop element or by an earlier initiation of the braking process or by a stronger braking.

The injection molding machine further comprises a braking device, which may be formed as stated above and a control device as described above. The drive unit, the first and the second stop member may also be formed as stated above. The drive unit is used for, preferably translational movement of the drive element, which subsequently drives the first stop element.

[0028] According to the invention, the drive unit has an electric motor, whereby the energy transmitted by the electric motor to the drive unit is reduced by the braking device.

SSwwidBsdses AT510 305B1 2014-03-15 is zable.

For this purpose, the braking device comprises an electrical switching unit which, when the value measured by the detection device is exceeded and compared with a reference value, drives the electric motor in order to reduce the energy transmitted to the drive unit. This can be done by reducing the engine speed, changing the direction of engine rotation, or by interrupting or reducing power to the engine. As a result, the first stop element and / or the drive element operatively connected to the first stop element are decelerated.

The invention further relates to an injection molding machine with a first stop element moved by a drive unit and a drive element operatively connected to the first stop element and with a second stop element, the first stop element impacting the second stop element in the course of the injection molding process. The injection molding machine further comprises a brake device, which may be formed as stated above and a control device as described above. The drive unit, the first and the second stop element and the drive element can also be designed as stated above.

According to the invention, it is provided that the brake device comprises a hydraulic and / or pneumatic brake element with which the first stop element is braked. This is particularly relevant for hydraulic and / or pneumatic injection molding machines.

In one embodiment of the invention, the braking device comprises a damping element which may be formed as a spring. This damping element can act as a passive braking element for the first stop element and / or the drive element. In this case, the detection device may comprise a measuring device with which the damping force, which results from the impact of the first stop element on the second stop element and the associated damping. In the case of a spring, this can be done by measuring the spring compression.

In one embodiment of the invention, the drive unit comprises a spindle drive with a spindle, which may also be assigned to the drive element.

The first stop member may be part of an ejector and ejector pins, and comprise a first stop surface, which are preferably translationally movable by the drive unit and strike or bounce for the purpose of Auswerfervorgangs on a arranged in or on the injection mold second stop element.

Additionally or alternatively, the first stop member may be part of the injection mold and arranged on a movably mounted platen first stop surface, which strikes or bounces from the drive unit for the closing operation on a second stop element comprehensive, fixed platen.

In one embodiment of the invention, the injection molding machine has a sliding element for driving the first stop element, wherein the sliding element is mounted relatively limited translationally movable relative to the drive element and thereby provides a reserve stroke for the drive unit available when the first stop element in his by the Impact location fixed mechanical end position is moved.

In this case, a guide element connected to the drive element may be provided for the sliding element, wherein the sliding element is mounted relative to the guide member limited translationally movable and guided by the guide element. In this case, a damping device, preferably a spring, can be arranged in the guide element in order to reduce the kinetic energy of the drive unit during the reserve stroke, ie during the trailing-off of the drive unit, by damping its movement.

1 is a cross-sectional view for explaining the principle of operation of an ejector device together with ejector pins connected thereto, FIG. 2 shows a sectional view of an ejector device, [0040] FIGS 2 marked area, FIG. 4 shows a schematic illustration of a control device according to the invention in conjunction with an injection molding machine. 6 shows an embodiment of a detection device for the impact force of the first stop element on the second stop element, [0044] FIG. 7 shows a further embodiment of a first embodiment 8 shows a further embodiment of a detection device for the impact force of the first stop element on the second stop element, FIG. 9 shows a further embodiment of an impact force detection device of the first. FIG 10 shows a further embodiment of a detection device for the impact force of the first stop element on the second stop element, [0048] FIG. 11 shows a further embodiment of an impact force detection device of the first [0049] FIGS. 12a, 12b show a schematic representation of the closing side of an injection molding machine, the first and second stop elements comprising closing mold halves of an injection mold. In Fig. 1 it is shown how an injection molded part is produced in the cavity 27 of the injection mold, wherein the closed cavity 27 is formed by the movable platen 8 and fixed mold mounting plates 8 'and via the recess 25 for an injection nozzle by means which plastic melt can be injected into the cavity 27. The arranged in Fig. 1 to the left of the movable platen 8 part of the injection molding machine with the ejector 1 will be explained with reference to FIGS. 2 and 3. After the plastic melt is at least partially solidified in the cavity 27, the injection mold is opened so that the injection molded part can be removed from the mold halves. For this purpose, a stop plate 28 is connected to the coupling piece 6 via a connecting element 26. The stop plate serves as a carrier of a total of three ejector 7. Moves the drive element 2 in the direction of the reindeer B, this movement is transmitted via the spring 4 on the sliding element 5, the stop plate 28 and the ejector 7. In particular, when the plastic melt is not yet solidified, it may occur that the injection molded part does not fall off the ejector pins 7. Upon cooling of the injection molded parts by the opening injection mold, these shrink on the ejector 7, so that can be difficult to solve the injection molded parts of the ejector 7. For this purpose, the stop plate 28 is driven at high speed in the direction of the injection mold, so that the first stop surface 30 bounces on the second stop surface 29 and stop the ejector 7 abruptly. As a result, the injection molded part drops from the ejector pins 7 due to the high acceleration that occurs. The stop plate 28 with the first stop surface 30 and the ejector pins 7 are part of the first stop element 35, 6/26

Merrecficial AT510 305B1 2014-03-15 impacting the second abutment member 36 comprising the second abutment surface 29.

The location of the stoppage of the first stop element 35 is determined by a braking device 38 or the impact of the first stop surface 30 on the second stop surface 29 and defines the mechanical end position of the ejector pins 7 and the sliding element 5. If an active braking device to achieve the mechanical end position is provided, this position can be determined beforehand by driving, so that the mechanical stroke of the ejector pins 7 is determined and stored as a desired course 32 in an electronic memory.

FIG. 2 shows an arrangement of an ejector device 1 which ejects an injection-molded part produced in an injection mold via ejector pins 7, not shown in this figure. The ejector device 1 has an electric motor 13 which has a belt drive which drives a spindle 2 'by means of a belt 14 and a belt pulley 15 which is rotationally fixedly connected to a spindle nut 17 via screws 16 and 16'. The spindle 2 'and the spindle 2' fixedly connected ejector plate 9, which is guided during the translational movement of a guide pin 10, are parts of the translationally movable drive element 2. The connected to the drive element 2, in particular with the spindle 2 'parts the ejector 1 are moved during the Auswerfervorganges relative to the injection mold, ie the injection mold translationally. On the ejector 9 a sleeve-shaped guide member 3 is fixed, in which the bolt-like formed sliding element 5 is mounted relative to the guide member 3 limited translationally movable. The ejector device 1 is designed as an ejector, wherein the sliding element 5 can be coupled to a coupling piece 6, wherein via the claw 12, the coupling piece 6 with the sliding element 5 is detachably connectable.

Not shown in this figure are connected to the coupling piece 6 ejector pins 7, which are arranged in or on the platen 8, which is part of the injection mold. If the sliding element 5 is moved with connected coupling piece 6 in the direction of the platen 8, the movement is transmitted to the stop plate 28 and the ejector 7, which can be moved to a second stop surface 29, which also defines the mechanical end position, not shown.

For transmitting the force transmitted from the electric motor 13 and the belt drive to the spindle 2, the sliding element 5 can be firmly connected to the ejector plate 9. In contrast, in the illustrated ejector 1 between the ejector 9 and the sliding element 5 in the guide element 3, a formed in the form of a spring 4 damping element 4 is arranged. The sliding element 5 is thus spring-loaded, whereby the movement of the spindle 2 'and the ejector plate 9 can be transmitted to the sliding element 5 and thus via the coupling piece 6 on the ejector 7. The bias voltage can correspond to the rated load of the electric motor 13.

The stop plate 28 and the Auswerferstifte 7 and thus also the sliding element 5 can be driven at high speed on the second stop surface 29 of the second stop member 36 and bounce on this, whereupon the ejector pins 7 and the sliding element 5 abruptly stop, creating a high Acceleration and a high jerk is transmitted so that the injection molded parts can fall off the ejector 7.

Such an impact leads due to the high inertia of the drive element 2, so among other things, the spindle 2 'and the ejector 9, a high load on the spindle 2' and in particular the bearings 18, 18 'of the spindle nut. In order to avoid such loads and the associated damage, the spindle 2 'and the ejector 9 can be even further moved at already stationary sliding element 5 due to the limited relative movability of the sliding element 5 relative to the guide element 3. The spring 4 is compressed and the spindle 2 'and the ejector 9 braked slowly and gently. The space between the sliding element 5 and the ejector plate 9 thus forms a wake and a reserve stroke for the drive element 2, in particular the spindle 2 'and the ejector plate 9. 7/26 The drive element 2 is driven by the electric motor 13 by a control device 31 in accordance with a an electronic memory of the control device 31 stored target course 32 moves. This movement is transmitted via the spring 4 and the sliding member 5 on the stop plate 28 and the ejector pins 7 and thus to the first stop member. Is due to a faulty setting the time at which the deceleration of the first stop element is initiated, too late, so that the drive element 2 presses with high force on the first stop element after it has already impacted on the second stop element and has reached its mechanical end position, This can lead to destruction of said components and thus the entire injection molding machine. However, the spring 4 can also be set such that compression takes place only with an excessive impact force.

A detecting device 11 is used to monitor the compression of the spring 4. As soon as the sliding member 5 in operative connection with the spring 4 exceeds a certain position, a braking operation is initiated by a braking device 38, which is not shown in this figure. The compression of the spring 4 is a measure of the force with which the first stop element 35, so the stop plate 28, is impacted on the second stop member 36, in particular on the second stop surface 29. For this purpose, the detection device 11 has a sensor, which may be, for example, an inductive sensor or a light sensor. The detection device 11 in this case has a calculation unit 37, by means of which the measured value can be compared with a reference value. If this reference value is exceeded, the braking device is actuated and activated by the control device 31 via the transmission device 33. By the braking device 38, for example, the electric motor 13 is turned off, reduces the engine speed, or reversing the direction of the motor 13 are initiated. In addition, the calculation unit 37 can change the set course 32 for the movement of the first stop element 35 and initiate the time of deceleration earlier, or increase the braking rate, so that future exceedances of the reference value can be avoided.

In the detail view of Fig. 3a, which shows the marked in Fig. 2 with A region, on the one hand a recess 6 'can be seen in the coupling piece, via which the ejector pins 7 can be attached to the coupling piece by means of a screw. Also visible are stop surfaces 19 of the guide element 3, which limit the mobility of the sliding element 5 relative to the sleeve-like guide element 3, so that during the Auswerfevorgangs a certain bias of the spring 4 for spring loading of the sliding element 5 is available, and the head 20 of the sliding element 5 abuts against these abutment surfaces 19. The sliding element 5 is thus formed as a stop pin which can abut against the stop surfaces 19 of the guide element 3.

The sensor element 21 can have a mirror, with which a light signal generated by the detection device 11 is reflected. Shifts due to the compression of the spring 4, the sensor element 21 relative to the ejector 9 fixed to the mounted part of the detection device 11, this light signal can no longer be reflected. In particular, the speed with which the sensor element 21 is moved out of the detection field of the detector device 11 is a measure of the impact force of the first stop element 35 on the second stop element 36. Instead of a mirror, the sensor element 21 as part of an inductive sensor for the detection device 11 be formed.

Fig. 3b shows the same view as Fig. 3a, only with now connected via the claw 12 sliding element 5 and coupling piece 6, as well as the coupling piece 6 fastened connecting element 26. The electric motor 13 drives the spindle 2 'and the ejector plate 9 comprehensive Drive element 2, so that the ejector 9 is moved translationally by means of the guide pin 10 along the longitudinal direction of the guide pin 10.

4 shows a schematic representation of a control device 31 according to the invention in conjunction with an injection molding machine 34, which has a first stop element 35

                                          second stopper member; second stop member 36 impacts.

From a detection device 11, which is part of the control device 31, the impact force or a measured variable associated therewith is measured. This is symbolized by the dashed line between the first stop element 35 and the detection device 11. A calculation unit 37 compares the measured variable with a reference value. When the reference value is exceeded, a braking device 38 is triggered by the control device 31 via the transmission device 33, which initiates a braking operation of the first stop element 35 or amplifies an already existing braking process. For this purpose, the brake device 38 is connected, for example, to the electric motor 13 and has control devices with which the electric motor is controlled, e.g. its direction of rotation can be reversed. However, the brake device 38 may also have hydraulic and / or pneumatic brake elements. In addition to the detection device 11, the transmission device 33 and the calculation unit 37, the control device 31 has further known electrical and electronic components. These elements can be connected via known connection means such as signal lines or at least partially arranged together on a printed circuit board.

5 shows a modification of a desired course 32 of the movement of the first stop element 35 as a result of a high impact force measured by the detection device 11. In an electronic memory of the control device 31 of the injection molding machine 34, a desired course 32 for the movement of the first stop element 35 is stored. At time 22, the braking ramp begins, with the braking of the first stop member 35 occurring at a certain rate. If, by measuring with the detection device 11, it emerges that the impact force on the second stop element 36 is too high, or if the first stop element 35 is driven when this is already in its mechanical end position, an earlier point in time 23 can be initiated Braking be selected. Additionally or alternatively, it is possible to enhance the braking action and to provide a higher braking rate, represented by the steeper deceleration ramp 24. As a result, the first stop element 35 comes to a standstill, both in terms of time and space, and damage to parts of the injection molding machine 34 can be avoided.

Fig. 6 shows an embodiment of a detection device 11. The motor 13 is connected via belt 14 with the first stop element 35 to be moved. The electric motor 13 is connected to a motor rocker 38, which is at least limited rotatably mounted about an axis 39. In the region of the electric motor 13, the detection device 11 is also arranged, wherein a sensor element 21, for example, an inductive sensor, is acted upon by a spring 40, and is thereby fixed to a different housing part from the electric motor 13. By the bias of the spring 40, the distance of the sensor element 21 is set to a measuring plate 41 which is fixedly connected to the electric motor 13. The bias of the spring 40 is selected so that the sensor element 21 at nominal load of the electric motor 13 assumes a reference distance to the measuring plate 41.

Now, if the electric motor 13 charged beyond the rated load addition, for example, because the impact force exceeds a critical value, or because the first stop member 35 abuts after impact on the second stop member 36 at this and thus the further movement of the first stop member 35 from second stop member 36 is obstructed despite driving the electric motor 13, this is rotated by the rotatable mounting of the electric motor 13 about the axis 39, so that the distance of the measuring plate 41 to the sensor element 21 changes. This change can be detected and transmitted via the control device 31 and the transmission device 33 to a brake device 38. Then it can reduce the engine power or shut off the electric motor 13 or reverse its direction of rotation. 9.26

FIG. 7 shows a partially cut-away view of another embodiment of a detection device 11 according to the invention with a deformation measuring device. FIG. On the spindle 2 ', a measuring diaphragm 42 is arranged with a strain gauge 43, wherein the measuring diaphragm 42 is partially formed bridge-shaped and has a measuring plate 41 in the region of the ejector 9. In the ejector 9, the sensor element 21, for example, arranged as an inductive sensor. As a result of an excessive impact force or a driving of the spindle 2 ', when the first stop element 35 already bears against the second stop element 36 after a crash, the measuring diaphragm 42, in particular the strain gage 43, is deformed. As a result of this deformation, the measuring plate 41 is displaced relative to the sensor element 42, wherein this relative movement is detected and transmitted from the control device 31 to the braking device 38 via the transmission device 33.

8 shows a further embodiment of a detection device 11 according to the invention, wherein a biasing wheel 44 for the belt 14 is acted upon by a spring 40. The load of the electric motor 13 and thus the overload due to an excessive impact force is reflected in the tension of the belt 14 again, so that the spring 40 is compressed in an excess. This can be detected by a sensor element 21 and transmitted to the brake device 38.

Fig. 9 shows in a partially broken view of a half of an ejector 1, a further embodiment of a detection device 11. On housing parts 46, 46 'of the bearing of the spindle 2', a spring 40 is arranged with a bias, wherein the bias voltage is a reference value , eg the rated power of the motor of the drive unit or the impact force of the first stop element 35 corresponds to the second stop element 36.

Upon impact of the first stop surface 30, not shown in this figure, on the second stop surface 29, a temporary deformation of the housing parts 46, 46 'or a change in the mutual position of these components, as a result of the bearing bush 45, the first housing part 46 is movable relative to the second housing part 46 'to a limited extent. A sensor element 21 can detect this displacement or deformation, which represent a measure of the impact force, and transmit it via the transmission device 33 to the brake device 38.

Fig. 10 shows in a partially broken view of the engine room of an injection molding machine 34, another embodiment of a detection device 11, in which case the displacement of the sensor element 21 relative to the housing 47 of the engine room detected and transmitted by the transmission device 33 to the brake device 38 becomes. The sensor element 21 may be biased by means of a spring 40 as in the previous figures, so that due to the deformation of the components, in particular the housing 47, in the course of the impact to be detected a relative positional shift of the sensor element 21 relative to the housing 47 results, which is a measure represents the impact force. In this figure, in addition to the ejector 9, the other components of the drive element 2 are arranged within the housing 48 of the ejector. About the coupling piece 6, the stop plate 28 is connected to the ejector 7 with the drive unit.

A further detection device 11 'with a further transmission device 33', for example in the form of a strain gauge, can be arranged on the housing outer wall.

FIG. 11 shows a further embodiment of a detection device 11 according to the invention which has a vibration measuring device. On the ejector 9 a measuring plate 41 and a sensor element 21 are arranged, which has a preset distance from the measuring plate 41. As a result of the impact of the first stop element 35 on the second stop element 36, the measuring plate 41 is vibrated, wherein the amplitude of the vibrations is a measure of the impact force. The sensor element 21, the inductive 10/26

Isfenseid »schis pi! Kr: i? AT510 305B1 2014-03-15

Sensor can be formed measures the distance to the measuring plate 41. If this falls below a predetermined reference value due to the vibrations of the measuring plate 41 is transmitted to the brake device 38, a signal for initiating or enhancing the braking process.

Fig. 12a shows a schematic view of a closing side of an injection molding machine 34, wherein by an electric motor 13 via a front plate 49 and a spindle 2 'by means of the toggle lever system 50, a movable mounted platen 8 in the direction of a fixed platen 8' is translationally movable. Instead of an electric motor and a hydraulic or pneumatic drive would be conceivable. Among other things, to guide this movement, and to stabilize the injection molding machine and transmission of the closing force, upper and lower spars 51 are provided. Both on the movable platen 8, as well as on the fixed platen 8 'is a respective mold half 52 and 52' respectively. In Fig. 12a is based on the non-closed mold halves 52, 52 ', and the angled knee lever system 50, an open clamping unit of the injection molding machine 34 is shown.

In Fig. 12b, the closing unit is closed, so that the mold halves 52 and 52 'adjoin one another. To ensure a fast production cycle, the closing unit is closed very quickly, with the first mold half 52 impinging on the second mold half 52 '. Too hard a bouncing can destroy the mold halves 52, 52 ', as well as the components associated therewith. The first stop element 35 therefore comprises the mold half 52 arranged on the movable platen 8, while the second stop element 36 comprises the mold half 52 'arranged on the fixed platen 8'.

The detection device 11 may be configured to measure the impact force of the mold half 52 on the mold half 52 'as well as to measure the impact force of the first stop surface 30 on the second stop surface 30 in the case of the ejector device 1 as in the above examples. Moreover, it is possible with one and the same detection device 11 to detect both the impact force of the mold halves 52, 52 'as well as the first stop surface 30 and the second stop surface 30. It is therefore with a control device 31 according to the invention, the closing of the mold halves 52, 52 'as well as the ejection of the injection molded control or controllable. 11/26

Claims (13)

MerreicfcLsche ;; 1. Injection molding machine with a first stop element (35) moved by a drive unit and a drive element (2) operatively connected to the first stop element (35) and with a second stop element (36), wherein the first stop element (35) ejector pins (7) and a first stop surface (30), which are preferably translationally movable by the drive unit (2) and for the Auswerfervorgang the first stop member in the course of the injection molding on the second stop element (36) which in or is arranged on the injection mold, bounces and with a control device (31), characterized in that a detection device (11) is provided, from which the force with which the first stop element (35) impacts the second stop element (36), measurable and via a transmission device (33) of the control device (31) can be fed. 2. Injection molding machine according to claim 1, characterized in that the force with which the first stop element (35) on the second stop element (36) impacts of the control device (31) is comparable to a reference value, wherein a braking device (38) for deceleration the first stop element and / or a drive element (2) operatively connected to the first stop element (35) when the reference value is exceeded by the control device (31) to initiate or increase the deceleration of the first stop element (35) and / or drive element (2) ) is controllable. 3. Injection molding machine according to claim 1 or 2, characterized in that an emergency stop device, preferably in the form of a circuit breaker, is provided. 4. Injection molding machine according to one of claims 1 to 3, characterized in that the detection device (11) a vibration measuring device and / or a deformation measuring device for measuring a due to the impact of the first stop element (35) on the second stop element (36) generated vibration or Deformation of the first stop element (35) and / or the second stop element (36). 5. Injection molding machine according to one of claims 1 to 4, characterized in that the detection device (11) has a measuring device for measuring a damping force, preferably a spring force, by the damping of the impact of the first stop element (35) on the second stop element (36). arises, has. 6. Injection molding machine according to one of claims 1 to 5, characterized in that an electronic memory is provided, are stored in the desired curves (32) for the movement of the first stop element (35), wherein a calculation unit (37) is provided with the reference curves (32) can be modified and stored in the electronic memory by a calculation program stored in the calculation unit (37) as a function of the measured variable determined by the detection device (11). 7. Injection molding machine according to one of claims 1 to 6, characterized in that a braking device for delaying the first stop element and / or the drive element is provided, wherein the drive unit comprises an electric motor (13) and wherein of the braking device (38) from the electric motor (13) to the drive unit transmitted energy can be reduced. 8. Injection molding machine according to one of claims 1 to 7, characterized in that a braking device for delaying the first stop element and / or the drive element is provided, wherein the braking device (38) comprises a hydraulic and / or pneumatic brake element. 9. Injection molding machine according to claim 7 or 8, characterized in that the braking device (38) comprises a damping element. 10. Injection molding machine according to claim 9, characterized in that the damping element is designed as a spring (4). 12/26 8thTOd »5C !!« S AT510 305B1 2014-03-15 11. Injection molding machine according to one of claims 1 to 10, characterized in that the drive unit comprises a spindle drive with a spindle (2 '). 12. Injection molding machine according to one of claims 1 to 11, characterized in that a sliding element (5) for driving the first stop element (35) are provided, wherein the sliding element (5) relative to the drive element (2) is mounted limited translationally movable. 13. Injection molding machine according to claim 12, characterized in that a with the drive element (2) connected to the guide element (3) for the sliding element (5) is provided, wherein the sliding element (5) relative to the guide element (3) mounted limited translationally movable and from Guiding element (3) is guided, and wherein a damping device, preferably a spring (4), in the guide element (3) is arranged. For this 13 sheets drawings 13/26