Processing machine

from Wikipedia, the free encyclopedia

Processing machines are material processing machines for the production of consumer goods . From predominantly non-metallic raw materials and intermediate products, they mainly produce consumer goods (e.g. food, pharmaceuticals, beverages) and non-technical consumer goods (e.g. textiles, household items) through targeted action on the processed goods. The processing machines also include packaging machines. In the production of mass consumer goods, processing machines achieve large outputs and are highly automated.

Definition

Mission objectives

Processing machines are used wherever mechanization and automation of the processing process is necessary to meet the demand of the consumer goods market . The following goals are pursued with different priorities:

  • Large quantities and high output.
  • High quality of the end product to ensure consumer safety and meet growing consumer needs.
  • Minimum unit costs with a high degree of individuality of the products and maximum flexibility in the processing process.

Often the goals contradict one another or are mutually exclusive, so that a focus on the individual application is necessary. Exemplary areas of application from the consumer goods industry are:

  • Food production (baked goods, meat products, etc.).
  • Manufacture of pharmaceutical products (tablets, capsules, ampoules, etc.).
  • Polygraphic   manufacturing processes (such as for books, magazines, packaging printing and processing).
  • Fruit and vegetable processing or beverage filling / packaging.

particularities

Natural and plastics often have unfavorable properties for processing in precise and fast-running machines. As a rule, the properties relevant to processing are unknown and cannot or can only be identified, recorded and quantified with difficulty. The properties often fluctuate, are usually complexly networked with one another and often change during the manufacturing process.

The manufacturing process places high demands on the kinematic and kinetic design of the machine. The processing task not infrequently requires complicated movement sequences that lead to unfavorable courses of forces and moments . As a result, high output and working speed result in high dynamic loads on the machines. Many functions arranged one behind the other and in parallel result in complex movement, control and regulation characteristics and demanding synchronization tasks. The multitude of different and complex interlinked processing steps must be coordinated with one another with high precision and process reliability.

Processing machines are often used in difficult production environments. Falling batch sizes and increasing flexibility in production require short set-up times and simple set-up processes . Heat (e.g. thermoforming), moisture (e.g. beverage filling), high demands on purity and quality (e.g. sterile production of pharmaceuticals) place high demands on material, structure and design. The operating conditions also differ greatly around the world. For example, it is often not possible to guarantee that the machines will be operated by optimally trained specialists. Legal framework conditions such as occupational health and safety or hygiene regulations form further requirements that must be met.

Often, several processing machines are combined into large systems that have complex overall behavior. The difficult manageability of the overall process makes its monitoring demanding and in the event of a malfunction often leads to long and complicated error propagation chains.

Demarcation

Process engineering systems realize chemical and biological material conversions and physical changes in the material system and are determined by this process engineering process. In contrast to the processing machines, the macro-geometry of the product plays no role or a subordinate role.

The transition to geometrically determined individual products (consumer goods) with a fixed quantity takes place in the subsequent processes in processing machines. The processes also include step-by-step packaging up to the usual and standardized containers in the logistics chain. Means of production are usually not manufactured on processing machines. The processing and processing of metallic materials and plastics for structural use is only carried out in exceptional cases (e.g. metal packaging, production of lightweight construction materials). As part of the manufacturing process, process engineering processes also occur in processing machines (e.g. baking tea biscuits, cooking dumplings), but they are not their only, structure-determining main component, but only a sub-process.

Structural design of a processing machine

Basic functional structure of a processing machine with its subsystems, their functional areas and their interactions.

The structural design of a processing machine is primarily determined by its functional structure

. A function describes qualitatively and quantitatively the changes that are to be implemented between the input and output of the functional system: Qualitatively, the change from characteristics in state 1 at the input to characteristics in state 2 at the output. Quantitatively the amount and the time. Depending on the purpose of the observation, u. In the early phases of the development process, quantitative values ​​are initially neglected. The overall function of a processing machine is the implementation of the processing tasks. The processing tasks include the steps to be carried out in the conversion and transformation of the material, the joining and handling . The functions of energy conversion and transformation as well as the information processing processes required for this are derived from this. The sub-functions of a processing machine are therefore divided into four functional areas: material, energy, signal and space. A group of structural elements that implement a sub-function is called a sub-system. The four subsystems are:

  • Processing system (fabric)
  • Propulsion or energy supply system (energy)
  • Control system (signal)
  • Support and envelope system (space)

The processing system

The processing system implements the sub-functions of the functional area substance. This is where the actual processing of the product takes place. The sub-functions include material processing and the material flow of the processed goods. The term processed goods includes all raw materials, preliminary products and the end product made from them. Processing goods can be in different forms:

  • Rope and thread form material (e.g. sewing thread)
  • Flat shaped goods (e.g. film)
  • Piece goods (e.g. stock cubes)
  • Bulk goods (e.g. nuts)
  • Highly viscous pasty goods (e.g. dough)
  • Liquid goods (e.g. milk)
  • Gases or aerosols (e.g. paint mist)

As a rule, multi-stage processing sequences convert the input product into the end product. A distinction is made between the following activity groups within the functional area:

  • Change in the condition of the processing goods: cutting, joining, shaping
  • Handling functions: dosing, arranging, conveying, storing

The effective pairing

Action pairing: scheme and example

The active pairing is the smallest sub-system of the functional area substance and implements the change in state of the processing product. The product to be processed and the working organ together form the active pairing. The working organ brings about changes in the state of the product through more or less targeted energy input. The place of interaction between the working organ and the processing material is called the point of action. A closer look at the pairing is carried out by the engineering discipline of processing technology. Examples of active pairs are:

  • Knife and paper
  • Dough hook and dough
  • Sealing jaw and foil
  • Extruder and granulate

Action pairing classes - working methods of action pairings

Active pairs can be divided into three classes according to their mode of operation. The main distinguishing features are the transport of the processing material through the point of action and its movement during processing.

Action pairing class 1 - batch mode: In batch mode, the material to be processed is stationary during processing. It is picked up and released by transport systems that are not part of the processing machine. As a rule, the goods to be processed are supplied and removed (e.g. filling / emptying of an active space) via the same geometric location. An internal machine transport does not take place. Class 1 active pairs are used where large quantities have to be processed with long exposure times. Your productivity is low. Application examples:

  • Kneading dough
  • Mixing household cleaners

Action pairing class 2 - intermittently working action pairings: When using action pairings of this type, the processing material moves periodically through the action point. During the action of the working organ, the processing material is at rest. As a rule, it is then transported to the next point of action. This action pairing class is selected if processing cannot be carried out on the moving product or if continuous processing would result in disproportionately high costs. Exemplary applications:

  • Forming, filling and sealing yogurt cups
  • Wrapping butter

Intermittently working pairs are significantly more productive than pairs in batch operation, since the supply and discharge of the processing material can take place at the same time at the point of action. However, challenges often arise due to the dynamic loads caused by the discontinuous movement of the work organs and the processing material, the load limits of which generally limit productivity.

Action pairing class 3 - continuously working action pairings: The processing material moves through the action point without interruption during the entire processing process. The working organs are carried along the path of movement of the goods to be processed or work without contact. Examples:

  • Sealing of tubular bags (longitudinal seam ultrasonically sealed with sealing rollers, transverse seam via sealing jaws carried along)
  • Continuous filling of bottles with simultaneous transport through the filling plant

Continuously working active pairs achieve the highest productivity. Their complicated implementation, however, tends to require more technical effort.

The drive system or energy supply system

The drive system is assigned to the energy function. Its task is to provide the energy required by the processing system in the required type, quantity and form. One also speaks of the energy supply system, since other functional areas such as the signal functional area are also supplied with energy.

Central drive systems

Central drive systems are characterized by one energy converter per machine. The individual working organs are driven mechanically via gears, often with the help of a so-called program shaft with cam disks . Energy and signal flow take place together on the mechanical work strand.

With a clever gear design, central drive systems enable effective torque and load balancing and thus good compensation for fluctuating torques. They have a reliable synchronization of the work organs, high quality of movement and safe emergency running properties and reach the highest working speeds. In contrast, the complex mechanics are subject to frictional forces and wear and tear and are relatively inflexible when it comes to adapting to changing processing conditions.

Decentralized drive systems

Decentrally driven folding machine for beverage cartons.

Decentralized drive systems have a single energy converter  for each working organ. The coordination takes place in the current state of the art via a higher-level electronic control. Energy and signal flow are separate.

Decentralized drive systems are used where long distances between the working organs have to be overcome or where flexible adaptation to changing or fluctuating processing tasks or conditions is required. Modularized assemblies are easier to implement with this concept, the mechanical structure is simpler. The quality of motion and synchronous operation of central drives can only be achieved with difficulty by decentralized drives at high working speeds and often not at all in the high-performance range. Large and variable moments of inertia and the associated vibrations as well as safe emergency running properties are current challenges.

Mixed forms of both types of drive are possible and common.

The control system

The control system is part of the signal functional area. It is responsible for the acquisition and processing of signals, influences the flow of energy to and in the work organs by acting on the drive system, serves to exchange information with other systems and contains the interfaces to the operator. Due to extensive functions with constantly new characteristics and requirements, one could also speak of an information processing system. The purpose of all functions, however, is always aimed at the (safe, effective and efficient) execution of the processing task of the machine or system, which justifies the term “control system”.

The most important functional groups of the control system are the signal acquisition and the signal processing including the necessary functions for signal storage and transmission. Two types of data are collected and processed by the control system:

  • Process data (including material data) for monitoring the processing process in the active pairing, e.g. B. Properties of the processing material, target values ​​or external influences
  • Operational data for monitoring the temporal and quantitative performance of functions, e.g. B. efficiency, availability, quantities, times

The data acquisition takes place depending on the objective before, in or after the active pairing. If the goal is to allow only processable processing goods to get into the active pairing and to discharge useless ones, the information is obtained before the active pairing. This enables the processing parameters to be adjusted. In borderline cases, the process can be canceled. If the signal detection is placed in the active pairing, faults and parameter deviations can be recognized immediately and the processing process can be corrected or canceled accordingly. Exceeding the tolerance of certain recorded values U. close to reject. Here there is the possibility of ejecting the products later. A property registration after the active pairing serves the quality control on the product and allows a readjustment in the process if necessary.

The support and envelope system

The support and envelope system (functional area space) is the most externally visible subsystem. It ensures the assignment and position of the elements and subsystems, separates the processing machine from its environment and its subsystems from one another.

The support system

The support system (also the frame) takes on the functions of supporting, guiding and storing and must absorb the static forces and moments resulting from operating loads. It ensures the required position tolerances and a sensible spatial arrangement of the subsystems. At the system boundaries, it creates mechanical interfaces to neighboring systems.

A distinction is made between the construction methods of frame systems mainly according to three aspects:

  • According to processing flow,
  • according to the arrangement of the functional areas,
  • according to frame variants according to morphological structure.
Single wall frame of a tubular bag machine in balcony construction: red the frame. On the left the drive system. On the right the processing system.

The processing flow is determined by the arrangement of the working bodies. A straight throughput of processing material results in a frame with a linear design. A version with several lanes is possible. Work organs arranged in a circle are implemented in drum or carousel designs. Continuously working machines with multiple arrangements of the work organs and comparatively longer exposure times can be implemented in a space-saving manner with this design.

Functional areas can be separated vertically and horizontally. The balcony construction arranges processing and drive on both sides of a partition wall. Particular advantages are good accessibility of the respective functional areas, their good delimitation from one another as well as clarity and cleanability. In the table construction, the processing is above and the drive below a horizontal separation. Multi-lane arrangements on a horizontal level, but also a tight concentration of functions on a small area, are possible and particularly in demand where gravity determines the relevant boundary conditions for the process.

The frame variants from a morphological point of view usually depend heavily on the construction methods mentioned above. A box frame can absorb large forces and offers free space below for the removal of substances. A portal or bridge frame is used for large track widths and areas, often in connection with a linear construction. Balcony structures are often designed as single-wall frames and are preferably used in this design for processing narrow strips. Compared to the single-wall frame, greater loads can be introduced into the double-walled frame and it offers greater rigidity. The open frame is often found in table construction and is beneficial for widely branched processing flows.

The envelope system

The envelope system prevents unwanted interactions with the environment. Unwanted transfers of energy (e.g. in the form of sound) across system or subsystem boundaries should be avoided, as should that of substances (e.g. leakage of operating materials) or information (e.g. industrial espionage). In conjunction with the control system, it protects against unauthorized access and guarantees accessibility and safe handling.

In the course of the increasing conditioning of the processing room, automatic cleaning and sterilization systems are also to be understood as part of this system. Like those mentioned above, they serve to maintain defined process conditions.

The internal machine process

Internal machine process for processing coffee beans and packaging coffee powder

The internal machine process describes in schematic form the sequence of the individual functions in the processing system. It shows the individual processing steps, their interconnection and the flow of material in the machine. The constructive implementation is not taken into account when considering the internal machine process. The individual functions are not represented by concrete pairs of effects, but by their process groups. This creates an image of the processing sequences in the machine that is independent of the processing principles, i.e. the specific technical implementation of the individual steps.

The internal machine process in the constructive development process

The development of the internal machine process is the beginning of the development of every processing machine. The systematic derivation of possible functional processes is based on the processing task to be fulfilled. The solution-neutral representation allows an assessment and variation independent of the constructive implementation. In later stages of development, the internal machine process is used to specifically search for solution principles for the individual functions. The simple definition of repeat assemblies is possible. A modularization of the machine is already supported in the development process.

Interconnection of individual functions

For the interconnection of the individual steps in the internal machine process, a distinction is made between the following basic circuit types:

Series connection: Several different or similar individual functions are connected in series. The multiple switching of similar functions is used to extend the processing time. An increase in productivity is only possible by increasing the working speed.

Parallel connection: Individual functions of the same type are connected in parallel. They are either centrally driven and rigidly connected or have independent individual drives. The latter can react individually to malfunctions and are characterized by very high reliability. With a large number of parallel functions, productivity can be increased without increasing the working speed.

Separating / branching: The material flow is divided into two or more material flows. If different processing steps follow after the separation, one speaks of separating or sorting. If the same individual functions follow, they are divided (e.g. into several lanes with the same functional sequence).

Merge: Two or more material flows are merged into one. The merging of different material flows is called joining. Organizing or conveying refers to the grouping of similar material flows.

Individual evidence

  1. ↑ G. Bleisch (Ed.): Lexicon packaging technology . 2nd Edition. B. Behr's Verlag, Hamburg 2003, ISBN 978-3-86022-974-3 , p. 431 .
  2. ↑ a b c d e f g K.-H. Grote, J. Feldhusen (Hrsg.): DUBBEL: Pocket book for mechanical engineering . 23rd edition. Springer-Verlag, Berlin / Heidelberg 2011, ISBN 978-3-642-17305-9 , pp. F38 - F47 .
  3. ↑ G. Bleisch, J.-P. Majschak, U. Weiß: Packaging processes - food, pharmaceutical and chemical industries . B. Behr's Verlag GmbH & Co. KG, Hamburg 2011, ISBN 978-3-89947-281-3 , p. 235 .
  4. ↑ a b c d E. Heidenreich, H. Goldhahn: Process engineering: processing technology . Ed .: G. Gruhn. VEB Deutscher Verlag basic industry, Leipzig 1978, p. 184 - 2011 .
  5. ↑ Horst Goldhahn: Structure of a system of processing principles . Dissertation submitted to the Faculty of Mechanical Engineering of the Science Council of the Technical University of Dresden to obtain the academic degree of Doctor of Science (Dr. – Ing.). Submission date: December 12, 1968, promotion date: September 18, 1969, pp. 20f.
  6. ↑ P. Römisch, M. Weiß: Project planning practice processing plants: planning process with calculation and simulation of system reliability . Springer Vieweg, Wiesbaden 2014, ISBN 978-3-658-02358-4 , p. 9 .
  7. ↑ VDI guideline 2680: Assembly and handling technology; Handling functions, handling devices; Terms, definitions, symbols, Beuth-Verlag GmbH, Berlin, 1990. The term “handling” is more broadly defined in this context than in VDI 2860, since flowable or pasty goods are also included in processing technology.
  8. ↑ G. Bleisch, J.-P. Majschak, U. Weiß: Packaging processes - food, pharmaceutical and chemical industries . B. Behr's Verlag GmbH & Co. KG, Hamburg 2011, ISBN 978-3-89947-281-3 , p. 191 .
  9. ↑ G. Bleisch (Ed.): Lexicon packaging technology . B. Behr's Verlag, Hamburg 2003, ISBN 978-3-86022-974-3 , p. 393 .
  10. ↑ G. Bleisch (Ed.): Lexicon packaging technology . B. Behr's Verlag, Hamburg 2003, ISBN 978-3-86022-974-3 , p. 400 .

literature

  • H. Herrnsdorf: Processing machines, history and definition . In: Mechanical engineering: wiss.-techn. Journal for research, development and construction . No. 27 . Verlag Technik, Berlin 1978, p. 252-256 .