CH703721A1 - Blow mold with a liftable molding. - Google Patents

Abstract

It is a blow molding tool (1) with at least one lift-off molding (4, 5) for the production of plastic containers in an extrusion or stretch blow process described, the two blow mold halves (2, 3) which are laterally displaceable relative to each other, and a molded part ( 4, 5) axially guided by the blow mold halves (2, 3) can be lifted comprises. When closed, the blow mold halves (2, 3) and the molded part (4, 5) delimit at least one blow mold cavity having a mouth opening. The blow molding tool (1) is equipped with at least one purely mechanical device (10, 20), which serves for lifting off the molded part (4, 5) when the blow mold halves (2, 3) move apart.

Description

The invention relates to a blow mold with a lift-off molding for the production of plastic containers in an extrusion or stretch blow molding process according to the preamble of patent claim 1.

The usual in the past containers made of white or stained, glass or ceramic are increasingly being replaced by plastic containers. In particular, for the packaging of fluid substances, such as beverages, household products, care products, cosmetics, etc., now mainly plastic containers are used. The low weight and the lower costs certainly play a significant role in this substitution. The use of recyclable plastic materials and the overall more favorable overall energy balance in their production also contribute to the consumer's acceptance of plastic containers, in particular of plastic bottles.

The production of plastic containers, in particular plastic bottles, for example made of polyethylene or polypropylene, often takes place in an extrusion blown, in particular in a Schlauchblasverfahren. In this case, an extruded head is usually used to continuously extrude a plastic tube, which may have one or more layers. The plastic tube is introduced in sections into a mold cavity of a blow molding tool, inflated by overpressure, cooled and removed from the mold. The blow molding tool usually consists of two blow mold halves, in each of which one half of the mold cavity is formed. The blow mold halves are periodically opened, closed and reopened to introduce a tube section in the mold cavity and to demold the finished container after inflation.

In this method, a so-called preform, which usually has an elongated, tube-like shape, at its one longitudinal end a bottom and at the other longitudinal end a neck region with shaped threaded portions or Like, inserted into a mold cavity of a blow molding tool and inflated by a medium blown with overpressure. In this case, the preform is additionally stretched in the axial direction with a retracting mandrel inserted through the neck opening. After the stretching / blowing process, the finished plastic container is removed from the blow mold.

The single-layer or multi-layer preform is usually produced in a separate injection molding process before the stretch blow molding process. It has also been proposed to produce preforms in a plastic web press process or by an extrusion blow process. Polypropylene or PET (polyethylene terephthalate) are mainly used as raw materials for the production of plastic containers in the stretch blow molding process. Polypropylene and PET have been tried and tested and their properties are well known. In the so-called one-step stretch blow molding process, the preform is inserted into the mold cavity of the blow molding tool immediately after its production and inflated to a plastic container and stretched. In many cases, however, the plastic containers are produced in a two-stage process, spatially and temporally separated from the stretch blow molding process, and temporarily stored for later use. In the later stretch blow molding process, the preforms are first heated again, introduced into the mold cavity of a blow molding tool, stretched with a stretching mandrel in the longitudinal direction and inflated by overpressure to form a plastic container according to the mold cavity. In this way, both processes, injection molding and stretch blow molding, can be operated separately and optimally.

Also in the stretch blow molding process usually a blow mold is used, which consists of two blow mold halves, in each of which a part of the mold cavity is formed. The blow mold halves are periodically opened, closed and reopened to insert, inflate and stretch the preform and demold the finished plastic container.

Many plastic containers, especially plastic bottles, have a concave, i. curved inwards, floor on. Plastic containers with relatively small concave bottom curvatures can still be demolded without problems from two-part blow molding tools without jamming the container or damaging the bottom. For more curved floors, the undercuts are too large to remove the plastic container from a two-part blow mold. However, plastic containers are also known which have a severely undercut shoulder area. For such plastic containers blow molds are used, which have a lift-off molding, for example, a lift-off floor or the shoulder area comprehensive lift-off component. Before opening the blow molding tool, first the liftable molding, for example the floor, is raised; only then the blow mold halves are moved apart, and the blown plastic container can be removed from the mold. By lifting the molding, for example, the bottom of the blow molding tool prevents the undercut obstructs the demolding of the mold cavity and leads to jamming of the plastic container.

The lifting of the molding is carried out hydraulically or pneumatically by arranged on the blow molding machine, stationary actuation and control devices. The production of plastic containers with more undercut areas, for example, with heavily undercut soils, is therefore always bound to a specific, equipped blowing machine. Although plastic containers with flat or less strongly undercut areas can be produced on this blow molding machine. Conversely, however, plastic containers with more undercut areas, such as floors, can not be made on each blow molding machine, i. a blow mold with a lift-off floor can not easily be used on a blow molding machine which does not have corresponding hydraulic or pneumatic lifting-off control means. The retrofitting of such a blow molding machine with the corresponding control devices is often out of the question of space and is also associated with relatively high costs. The constraint of the production of plastic containers with heavily undercut areas of very specific blow molding machines therefore often leads to major logistical problems and is undesirable for economic but also for ecological reasons.

Object of the present invention is therefore to remedy these disadvantages of known from the prior art blow molding machines for extrusion and stretch blow molding. The possibility should be created to be able to produce plastic containers with more or less strongly undercut bottoms or shoulder areas on any blow molding machines. It should not matter whether the blow molding machine is equipped with the corresponding hydraulic or pneumatic control devices for lifting the lift-off molding from the blow mold or not. Modifications to the blowing machines should be avoided.

These objects are achieved according to the invention by a blow molding tool with a lift-off molding, which has the features listed in claim 1. Further developments and advantageous and preferred embodiments of the invention are the subject of the dependent claims.

The invention proposes a blow molding tool with at least one lift-off molding for the production of plastic containers in an extrusion or stretch blow molding process, the two blow mold halves, which are laterally displaceable relative to each other, and a molded part, which is axially guided by the blow mold halves, includes. When closed, the blow mold halves and the molding define at least one blow mold cavity having a mouth opening. The blow molding tool is equipped with at least one purely mechanical device which serves to lift the molded part when moving apart of the blow mold halves.

In contrast to the known from the prior art blow molds with abhebbarem molding, which require the lifting of the molding on the blow molding machine arranged hydraulic or pneumatic control devices takes place in the inventive blow mold lifting the molding by means of mechanical devices that already formed on the blow mold. The blow molding tool according to the invention does not require special hydraulic or pneumatic actuation or control devices. As a result, if necessary, the blow molding tool can be very easily transferred from one blow molding machine to another. This increases the flexibility of the blow molding machines. Costly conversions and extensions of special control devices can be avoided. By replacing an existing blow molding tool against a blow molding tool equipped according to the invention with integrated mechanical devices for lifting the molded part, the existing blow molding machines can be used better and more efficiently. Logistical problems can be counteracted very effectively. Unnecessary transport of empties can be avoided.

By the mechanical means for lifting the molding is arranged on at least one of the substantially perpendicular to a parting plane of the blow mold halves side surface of the blow molding tool, the blow molding tool can be made very simple. The arrangement of the mechanical device outside on the side surface of the blow molding tool allows a relatively simple construction of the mechanical device.

The mechanical means for lifting the molding of the blow mold can be relatively easily equipped, if they are arranged on both substantially perpendicular to the parting plane of the blow mold halves extending side surfaces of the blow mold. This ensures that even with simple constructions of the mechanical devices, the molded part is lifted uniformly everywhere, and the forces occurring during lifting can be distributed symmetrically and dissipated.

In a suitable embodiment variant of the blow molding tool, the lift-off molded part is designed in two parts, with each blow mold half being assigned a lift-off molded part section. On each of the substantially perpendicular to the parting plane of the blow mold halves side surface of the blow molding tool mechanical means for lifting the two mold sections are provided. Each liftable molding section is associated with a mechanical device on both side surfaces of the blow molding tool. These effect independently, solely by their geometric arrangement and training a uniform lifting of the molding sections when moving apart of the two blow mold halves.

In one embodiment of the invention, each mechanical device comprises a link control. Gate controls are purely mechanical control elements and lead solely due to the formation of the scenes and the components cooperating therewith to a uniform relative movement of the associated components, in the specific case to a uniform lifting of the molding sections of the blow mold halves.

The slide control comprises, for example, a format part connected to a mold part section, which extends from the mold part section over a part of the side surface of a first of the two blow mold halves. At its free end, the format part is provided with a control cam, which cooperates with a power transmission arm, which is articulated in an axially height-fixed manner on the side surface of the second blow mold half and extends in the direction of the first blow mold half. This very simple variant of a slide control consists essentially of only two components, the format part with the control cam and the power transmission arm, which cooperates with the control cam. To open the blow mold, the blow mold halves are moved apart. In this case, the axially height-fixed power transmission arm is in engagement with the control cam on the format part. Since the power transmission arm is fixed in terms of its axial height position, the molded part section connected to the format part is forcibly lifted when moving apart of the blow mold halves according to the control curve. The two components of the slide control are easy to manufacture and consist for example of commercially available steel. The mechanically cooperating sections of the components may additionally be hardened or provided with a friction-reducing coating.

In a further embodiment of the blow molding tool, the power transmission arm at its free end to an exchangeable guide element, which forms an abutment for the control cam in cooperation with the format part. The guide element can be designed especially for the mechanical loads occurring during the interaction with the control curve, for example, be specially hardened or coated. In the case of wear, the guide element can be easily replaced. For example, the guide element is designed as a rotatably mounted disc. The rotatability of the disc reduces the frictional forces and the resulting wear. In addition, the rotatably mounted disc also reduces the forces that must be expended for moving apart of the blow mold halves.

The course of the cam at the free end of the format part determines the course of the lifting movement of the soil. In an exemplary embodiment of the invention, the control cam on an inlet slope, a horizontal portion and an outlet slope. The inlet slope ensures a relatively gentle introduction of the lifting forces on the power transmission. The horizontal portion ensures that the molding portion remains open during demoulding of the inflated plastic container. The outlet slope causes the molding section is gently deposited again on the blow mold half. The steepness of the inlet and the outlet slope determine how quickly the molding section is lifted or replaced at a predetermined opening or closing speed of the blow mold halves.

A further embodiment of the invention provides that the control curve having format part is detachably connected to the molding portion. This makes it very easy to replace the format part. Depending on the requirements format part with different cams can be used in this way to change the course of the lifting movement of the molding section. This makes it very easy to influence the lifting operation of the molded part of the blow mold halves. In contrast to the known blow molding machines and blow molding tools, no hydraulic or pneumatic control parameters need to be changed for this, which generally necessitate a large number of further changes. Even a change in the opening and closing speed of the blow mold halves does not change the basic characteristic of the lift-off or the lowering movement of the molded part.

In a further embodiment of the invention can be provided that the power transmission arm is deflectable perpendicular to the side surface of the blow molding tool against the return action of a return element. In addition, a lateral Ausstellschräge is provided on the side surface of the first Blasformhälfte at an axial distance from the format part, over which the power transmission arm is laterally deflected when moving the two blow mold halves. The lateral deflection of the power transmission arm is prevented from coming into engagement with the control cam of the format part when the blow mold halves move together. At the end of the closing process, the power transmission arm pivots back to its original position and comes back into engagement with the control surface of the format part. As a result, the molding remains in the lowered state upon closure of the blow molding tool and is only lifted again when the blow mold is opened again.

A projecting from one of the control slope underside of the free end of the Kraftübertragungsarms projecting guide pin which is movable along the lateral Ausstellschräge when moving the blow mold halves, facilitates the lateral deflection of the power transmission arm. The engagement element is a wear part, which is easily replaceable if necessary.

A further embodiment of the invention provides that at the free end of Kraftübertragungsarms, the rotatably mounted disc opposite, a guide shaft is arranged, which is supported upon opening of the blow molding on a guide surface. This reduces the mechanical stress on the bearing of the power transmission arm in the mounting block.

The format part and the associated power transmission arms are conveniently arranged in pairs on the two side surfaces of the blow molding tool. In each case, a format part on a first blow mold half and the associated, cooperating with the control cam on the format part power transmission arm are arranged on the second blow mold half. Thus, each blow mold half at its two approximately perpendicular to the parting plane side surfaces on a format part and an arranged below Kraftübertragungsarm.

The lift-off from the blow mold halves molding may be a bottom of the blow mold or a shoulder portion of the Blasformkavität comprehensive component. The blow molding tool may also have a lift-off bottom and a lift-off shoulder portion.

For the mass production of plastic containers, the blow molding tool is formed in a further embodiment of the invention as a multiple tool. The blow mold halves in the contracted state limit several mold cavities with mouth openings.

Further advantages and embodiments of the invention will become apparent from the following description of an embodiment with reference to the schematic drawings. It shows in not to scale representation: <Tb> FIG. 1 <sep> an inventive blow mold in the closed state; <Tb> FIG. 2 <sep> is a detail of the blow molding tool of Fig. 1; <Tb> FIG. 3 <sep> the blow molding tool of Fig. 1 during the opening phase; <Tb> FIG. 4 <sep> an enlarged detail of the blow mold in the opening phase; <Tb> FIG. 5 <sep> the blow mold in fully open position; <Tb> FIG. 6 <sep> the blow mold during the closing phase; <Tb> FIG. 7 <sep> the blow molding tool during the closing phase, shortly before reaching the closed state; <Tb> FIG. Fig. 8 shows the blow molding tool of Fig. 7 in a view of the opposite side surface; and <Tb> FIG. 9 <sep> a detailed representation of the blow molding tool shortly before reaching the closed state.

In the following the invention will be explained using the example of a blow mold with a lift-off floor. It is understood, however, that the invention is not limited to a blow mold with a lift-off floor. The form part which can be lifted off from the blow mold halves can also be a component comprising a shoulder section of the blow mold cavity. Finally, the blow-molding tool can have both a lift-off floor and a lift-off shoulder section.

The exemplary embodiment of a blow molding tool designed according to the invention described in the figures described below carries the reference numeral 1 in its entirety. It comprises a first and a second blow mold half 2 and 3 and a bottom consisting of two bottom sections 4 associated with the blow mold halves 2, 3 or 5 exists. Fig. 1 shows the blow mold 1 in the fully closed state. The blow mold halves 2, 3 are shown in the closed state and touch each other along a parting plane E. The two blow mold halves 2, 3 are connected at their two parallel to the dividing plane E backsides with mounting plates 6 and 7, with which the blow mold 1 in a known manner can be mounted in a blow molding machine.

The blow molding tool 1 has two side surfaces 8, 9 which extend approximately perpendicular to the parting plane E. The perspective view of the blow molding tool 1 in FIG. 1 shows the frontal side surface 8 facing the viewer. The side face 9 running parallel thereto is not visible. On the frontal side surface 8 mechanical devices 10 and 20 are arranged, which serve to lift off the bottom of the blow molding tool 1 forming bottom sections 4, 5. The two mechanical devices 10, 20 are constructed largely identical. The mechanical means 10 for lifting the bottom portion 4 of the first (left) blow mold 2 comprise a format part 11, which is detachably connected to the bottom portion 4, and a power transmission arm 13, which is mounted axially fixed in height on the second (right) blow mold half 3 and extends in the direction of the first blow mold half 2. The power transmission arm 13 is fixed in a mounting block 14 and held there laterally pivotable. The lateral pivoting is indicated in Fig. 1 by the arrow P. The structure of the mechanical device 20 for lifting the bottom section 5 from the second blow mold half 3 is analogous. It has a format part 21, which is detachably connected to the second blow mold half 3 associated bottom portion 5, and a power transmission arm 23 which is mounted axially fixed in height on the side surface 8 of the first blow mold half 2 in a mounting block 24. Also, the power transmission arm 23 of the second mechanical device 20 is laterally pivotable, which is indicated in Fig. 1 by a further arrow P. On the side face 9, which is not visible in FIG. 1, two further mechanical devices are arranged, which are constructed analogously to the two described mechanical devices 10, 20 on the frontal side surface 8.

The mechanical devices 10, 20 are designed as gate controls. The lifting of the bottom sections 4, 5 takes place by the interaction of the axially height-fixed power transmission arms 13, 23 provided with the format part 11, 21 control surfaces (not visible in Fig. 1). For this purpose, a rotatably mounted disc 15, 25 mounted at the free end of each Kraftübertragungsarms 13, 23, on whose side surface 8 facing inside. The rotatably mounted disc 15, 25 acts on opening the blow mold in such a way with the arranged on the format part 11, 21 control cam that the bottom part 4, 5 is lifted from the blow mold half 2, 3.

Fig. 2 shows a detailed view of the Kraftübertragungsarms 13 of the mechanical device 10 of FIG. 1. The formed on the format part 11 control cam is covered by the rotatably mounted disc 15. From the illustration it can be seen that the rotatably mounted disc 15 opposite a guide shaft 16 may be provided, via which the power transmission arm 13 is supported on a guide rail 17. A pin whose function will be explained in more detail below, protrudes from the underside of the free end of the power transmission 13 and carries the reference numeral 19th

Fig. 3 shows the blow mold 1 of Fig. 1 during the phase of opening with partially disassembled blow mold halves 2, 3. The two mechanical means for lifting the bottom sections 4, 5 are in turn provided with the reference numerals 10 and 20 respectively. The power transmission arms 13, 23 cooperate with provided on the format part 11, 21 control cams 12, 22 together. After the power transmission arms 13, 23 are axially fixed in height and the format part 11, 21 are firmly connected to the bottom sections 4, 5, the bottom portions 4, 5 are lifted from the associated blow mold halves 2, 3 by the interaction of the two sliding control elements.

Fig. 4 shows an enlarged view of the blow molding tool 1 of Fig. 3. The blow mold halves bear the reference numerals 2 and 3, respectively. The associated raised floor sections are designated 4 and 5 respectively. In the view a formed in the first (left) Blasformhälfte 2 half-cavity of the mold cavity M is indicated. Between the two blow mold halves a portion of a plastic container C with an inwardly curved, undercut bottom B is shown. The formed in the raised bottom portion 4, associated molding projection is provided with the reference symbol U. The illustration shows the mechanical device 10 for lifting the bottom portion 4. The format part with the control cam 12 carries the reference numeral 11. The mounted in the mounting block 14 power transmission arm is denoted by 13. From the illustration it is clear that without lifting the bottom sections 4, 5 of the mold projection U in the inwardly curved (undercut) bottom B of the container C protrude and thereby hinder its removal from the mold cavity M.

Fig. 5 shows the blow mold 1 in its fully open position in which the inflated in the mold cavity M and possibly stretched and demolded plastic container C is removed. It can also be seen from the illustration that the mold cavity M has an outlet opening O at the side of the blow molding tool facing away from the bottom sections 4, 5. During operation, a blowing mandrel or a blowing / stretching mandrel is retracted through the opening O. The blow mold halves 2, 3 are moved apart so far that the power transmission arms 13, 23 are out of engagement with the control cams 12, 22 of the attached to the bottom sections 4, 5 format part 11, 21. As a result, the bottom sections 4, 5 are lowered back onto the blow mold halves 2, 3. The format part 11, 21 are detachably connected to the bottom sections 4, 5. This allows easy replacement of the same, for example, to mount format part with differently shaped cams. The control cams 12, 22 shown, for example, have an inlet slope, a horizontal portion and an outlet slope. The course of the control cam 12, 22 at the free end of each format part 11, 21 determines the course of the lifting movement of the bottom sections 4, 5. The inlet slope provides for a relatively gentle initiation of Abhebekräfte on the power transmission arm 13, 23. The horizontal section ensures that the bottom portion 4, 5 remains open during demoulding of the inflated plastic container C. The outlet slope causes the bottom section 4, 5 is gently deposited again on the Blasformhälfte 2, 3. The steepness of the inlet and the outlet slope determine how fast the bottom section 4, 5 at a predetermined opening or closing speed of the blow mold halves 2, 3 is lifted or replaced. In an alternative embodiment, the control curve at the free end of each format part also simply consist of a slope, for example, has an inclination angle of 30 ° to 65 °, preferably of about 45 °.

Below the free ends of the power transmission arms 13, 23 are arranged on the frontal side surfaces 8 of the blow mold halves 2, 3 Ausstellschrägen 18, 28, whose function will be explained in more detail below.

In the illustration, the arranged on the opposite side surface 9 of the Blaswerkzeugs 1 mechanical devices are indicated, which are analogous to the arranged on the frontal side surface 8 mechanical means 10, 20 are formed.

Fig. 6-8 show perspective views of the blow molding tool 1 in two different stages of the closing process. The state of the blow molding tool 1 shown in FIG. 8 corresponds to that shown in FIG. 7. Only FIG. 8 shows the blow molding tool 1 with a view of the side surface 9 facing away from the other representations. Identical reference signs denote the same elements as in the preceding illustrations. During closing, the guide pin 29 protruding from the underside of the power transmission arm 23 comes into abutment with the tilting bevel 28. As a result, the power transmission arm 23 is laterally deflected substantially perpendicular to the side surface 8 against the restoring force of a return element, for example a return spring arranged in the mounting base 24 , As a result, the rotatable disk 25 arranged at the free end of the power transmission arm 23 remains out of engagement with the control surface 22 of the format part 21. It is understood that the same happens to the power transmission arm 13 and the two power transmission arms on the opposite side surface. This prevents the bottom sections 4, 5 from being unnecessarily lifted off the blow mold halves 2, 3 during the closing of the blow molding tool 1.

Fig. 9 shows an enlarged view of the mechanical devices 10, 20 of Fig. 7. It can be clearly seen that the power transmission arms 13, 23 are laterally deflected outwards, so that the rotatable discs 15, 25 out of engagement with the control surfaces the format part 11, 21 remain. The projecting from the power transmission arm 13 guide pin 19 slides along a projecting vertically from the guide rail 17 sliding rib 71, which ensures that the rotatable disc 15 during the closing process not along the format part 11 grinds or the guide shaft 16 is not applied to the guide rail. Only when the closed position of the blow molding tool 1 is reached, the power transmission arms pivot back in the direction of the side surface in its initial position. The rotatable disc 15 is then located immediately in front of the inlet slope of the control cam 12 of the format part 11; the guide shaft 16 rests on the guide rail 17. Then the blow molding tool 1 is again in its starting position shown in FIG. 1.

The preceding description of the figures is limited to the details required for understanding the invention. It is understood, however, that the blow molding tool has all the components required for its function. For example, locking elements for the blow mold halves and for the bottom portions are provided so that the blow mold remains closed at the internal pressures occurring during the blow or stretch blow molding. Also, the blow mold is provided with a variety of holes so that the surfaces of the mold cavity can be cooled, etc.

Claims (16)

1. Blow mold with a lift-off molding for the production of plastic containers in an extrusion or stretch blow molding process, comprising two blow mold halves (2, 3) which are laterally displaceable relative to each other, and at least one molded part (4, 5), which is axially guided by the Blow mold halves (2, 3) can be lifted, wherein the blow mold halves (2, 3) and the molded part (4, 5) in the closed state at least one Blasformkavität (M) limit, having a mouth opening (O), characterized in that the blow mold (1) at least one purely mechanical device (10, 20) comprises, which serves for lifting the molding (4, 5) when moving apart of the blow mold halves (2, 3). 2. Blow mold according to claim 1, characterized in that the mechanical means (10, 20) for lifting the molding (4, 5) on at least one of the substantially perpendicular to a parting plane (E) of the blow mold halves (2, 3) extending side surface (8, 9) of the blow mold halves is arranged. 3. Blow mold according to claim 2, characterized in that at both substantially perpendicular to the parting plane (E) of the blow mold halves (2, 3) extending side surfaces (8, 9) mechanical means (10, 20) for lifting the molding (4, 5 ) are arranged. 4. Blow mold according to claim 2 or 3, characterized in that the lift-off molding is formed in two parts, each of the blow mold halves (2, 3) a lift-off molding portion (4, 5) is associated, and that at each of the substantially perpendicular to the parting plane (E) of the blow mold halves (2, 3) extending side surfaces (8, 9) of the blow mold halves (2, 3) each have two mechanical means 810, 20) for lifting the two mold part sections (4, 5) are provided. 5. Blow mold according to claim 4, characterized in that each mechanical device (10, 20) comprises a link control. 6. blow mold according to claim 5, characterized in that the link control comprises a with the molding portion (4, 5) connected format part (11, 21) extending from the molding portion of a part of the side surface (8, 9) of a first of the two Blasformhälften extends and at its free end with a cam (12, 22) is provided, which cooperates with a Kraftübertragungsarm (13, 23) which is fixed axially fixed in height on the side surface (8, 9) of the second Blasformhälfte and in the direction of first blow mold half extends. 7. Blow mold according to claim 6, characterized in that the power transmission arm (13, 23) has at its free end an exchangeable guide element, which forms an abutment for the control cam (12, 22) in cooperation with the format part (11, 21). 8. blow mold according to claim 7, characterized in that the guide element is a rotatably mounted disc (15, 25). 9. Blow mold according to one of claims 6-9, characterized in that the control cam (12, 22) has an inlet slope, a horizontal portion and an outlet slope. 10. Blow mold according to one of claims 6 - 9, characterized in that the format part (11, 21) is releasably connected to the lift-off molding portion (4, 5). 11. Blow mold according to one of claims 6-10, characterized in that the force transmission arm (13, 23) perpendicular to the side surface (8, 9) is deflectable against the return action of a return element, and that on the side surface of the first blow mold at an axial distance of the format part (11, 21) a lateral Ausstellschräge (18, 28) is provided, via which the power transmission arm (13, 23) when moving the two blow mold halves (2, 3) is laterally deflectable. 12. Blow mold according to claim 11, characterized in that from one of the Ausstellschräge (18, 28) facing the underside of the free end of the Kraftübertragungsarms (13, 23), a guide pin (19, 29) protrudes, which upon collapse of the blow mold halves (2, 3) with the lateral Ausstellschräge (18, 28) cooperates. 13. Blow mold according to one of claims 8-12, characterized in that at the free end of the Kraftübertragungsarms (13, 23), the rotatable disc (15, 25) opposite, a guide shaft (16, 26) is arranged, which when opening of the blow molding tool (1) on a guide rail (17, 27) is supported. 14. Blow mold according to one of claims 6-13, characterized in that at the two side surfaces (8, 9) of each blow mold half (2, 3) in each case one with the associated mold part section (4, 5) connected format part (11, 21) Control cam (12, 22) and an axially höhenfixierter Kraftübertragungsarm (13, 23) are arranged with the control cams (12, 22) arranged on the two side surface (8, 9) of the opposite Blasformhälfte format part (11, 21) and interact with the power transmission arms (13, 23) mounted at a fixed height there. 15. Blow mold according to one of the preceding claims, characterized in that the of the blow mold halves (2, 3) liftable molding (4, 5) is a blow mold bottom and / or a shoulder portion of the Blasformkavität comprehensive component of the blow mold. 16. Blow mold according to one of the preceding claims, characterized in that the blow mold halves (2, 3) in the closed state, a plurality of mold cavities (M) with mouth openings (O) limit.