This dissertation in the engineering study of the Engineering technology deals with the proposal of the unit production technology of two pieces of the tool for cold forming of the material X 45 NiCrMo 4, standard W. Nr material number 1. 2767. The production is on the demand and is therefore trial, because the specified tool has not been till now fabricated. The thesis describes an analysis of manufactured components, as well as a description of the material used, a description of the available technologies that were used and a design of production technology. The production will include these methods: turning, grinding, electro erosive deepening and polishing.

This master’s thesis created in the master studies of the M-STG Manufacturing technology is focused on the manufacturing of a part of a garage automatic door lock by a compound tool. The part is made of a rolled steel coil of the S275JR material with the thickness of 2 mm. The number of parts manufactured per year equals to 600 000. Literary studies deals with the issues of cutting and bending. On the basis of the most advantageous manufacturing variant and technological calculations the compound tool is designed. As a working machine the eccentric press LEK 160 is chosen. In the economical evaluation part, the calculations to finding out when the manufactory becomes profitable are carried out.

The submitted project was created in the engineering studies of M-STG Machinery technologies and it is focused on problematics of production of reinforcement door locking. Component will be manufactured by cutting and bending technologies and used material is aluminium alloy EN AW-3103. As a manufacturing stock is used roll of sheet. Manufacturing series is 400 000 pieces a year. Literary study was created according to the mentioned technologies. After the control calculation was proccesed, the compound tool was designed. As a working machine was selected accentric press SMERAL LE 250/40, where the compound tool will be clamped.

Requirements for the creation of a new technological process of manufacturing of towing hooks were cost savings by optimizing the initial blank and by creating semi automatic workplace. Selecting longitudinal rolling technology for manufacturing preform piece occurs to shorten production times and substantial material savings. By rolling of blank are secured always the exact dimensions of the preform piece and through a chain conveyors is facilitated handling with material for workers and reduced production time of forging line. By introduction of the proposed manufacturing method of towing hooks depending on the size of the series 30000 hooks per year will be achieved annually savings of over 4.000.000 CZK. Return of investments for the acquisition and adjustment of forging rolls and conveyors is 2,2 years.

The thesis deals with the design of a suitable technology for serial production of a pin. The component material is structural steel 11,320 5R. Due to the series production and material savings, the molding technology was chosen to be cold. For production, the CM 4-5 ECO HATEBUR process press was designed with a nominal force of 1 700 kN. Progressive tool and drawing documentation of tools for the final operation were also designed. The tool load was verified by manual calculation, and the finite element method was calculated to heat the formed blank due to molding.

The present work deals with some aspects of the fluidmechanics of paper-making,more specifically partial dewateringduring roll forming. The study is mainly experimental. Pressureand wire position measurements have been carried out in anexperimental facility, the KTH-Former,which models the rollforming zone of a paper machine. Measurements are carried out with pure water for threedifferent wires (fabrics): A non-permeable,a semi-permeable anda conventional wire. Although not used in paper making,thenon-permeable wire is useful when trying to understand thefundamental mechanics of roll forming.The semi-permeable wirewith finite but low permeability is used to model the effectsof the fibre web on the drainage. Tests have mainly been carried out for different wiretensions and different jet speeds. It is shown that the localcurvature of the wire is strongly correlated to the dewateringpressure. The conventiona wire shows a single pressure peak causingcomplete de- watering in the first part of the dewateringzone.The pressure distributions for the non-and semi-permeablewires are found to show two consecutive pressure peaks followedby a suction peak where the wire is taken of the roll.Thisoscillating behaviour is due to capillary waves where the wiretension plays the role of surface tension on a free surface.Thewavy behaviour of the wire is recovered from an analyticalmodel and the effect is governed by a dimensionless Webernumber. The measured wave lengths correspond well to thosegiven by the theory. When the wire tension is high,i.e.a high dewateringpressure,the flow in the impingement region collapses when thedynamic pressure of the headbox jet is about half of thedewatering pressure. It is shown experimentally that the localdrainage shows a correlation to the dewatering pressure andhence to the wire curvature. / NR 20140805

Compliant mechanisms are useful for improving existing machines and creating new ones that were not previously possible. They also help us to think of new methods and technologies needed to both improve existing systems as well as manufacture systems that have not been done before. The purpose of this thesis is to show novel implementations of compliant mechanisms into folding systems, and to show new methods for fabricating such mechanisms with nontraditional materials and on difficult scales. Folding systems are shown in furniture applications with chairs, stools, and childcare furniture applications as results of research into how such structures could be created with compliant mechanisms to be deployed from a flat state. Compliant mechanisms are also shown to be folded by a laser into simple mechanisms and into a potentially more complex parabolic reflector. Small-scale flexible (or compliant) mechanisms are valuable in replacing rigid components while retaining comparable motion and behavior. However, fabricating such mechanisms on this scale (from 0.01 to 10 cm thick) proves difficult, especially with thin sheet metals. The manufacturing method of laser forming, which uses a laser to cut and bend metal into desired shapes, could facilitate this fabrication. However, specific methods for designing mechanisms formed by lasers need to be developed. This work presents laser forming as a means for creating compliant mechanisms on this scale with thin sheet metal. The unique challenges for designing mechanisms to be laser-formed are explored, and new adaptations of existing designs are fabricated and discussed. The design of basic "building blocks" and features are developed for several mechanisms: a parallel-guided mechanism, a cross-axis flexural pivot, a LET joint array, a split-tube flexure, and a bi-stable switch. These mechanisms are shown to perform repeatable behavior and motion comparable to existing non-laser-formed versions. The further possibilities for fabricating compliant mechanisms with laser forming are explored, as advanced applications can benefit from using lasers to create compliant mechanisms from thin sheet metal. One such possible system is a parabolic reflector, which is useful for making solar collectors and antennas. Such shapes have been developed in various patterns and typically manufactured out of rigid components. Applications for these systems could benefit from paraboloids that can fold up and be deployed into a final shape. This work presents a conceptual method for designing a flat-foldable paraboloid and a means for its fabrication using laser forming.

For graphs G and H, a set S⊆V(G) is an H-forming set of G if for every v∈V(G)-S, there exists a subset R⊆S, where |R|=|V(H)|-1, such that the subgraph induced by R∪{v} contains H as a subgraph (not necessarily induced). The minimum cardinality of an H-forming set of G is the H-forming number γ {H}(G). The H-forming number of G is a generalization of the domination number γ(G) because γ(G)=γ {P2}(G) . We show that γ(G)γ {P3}(G)γ t(G), where γ t(G) is the total domination number of G. For a nontrivial tree T, we show that γ {P3}(T)=γ t(T). We also define independent P 3-forming sets, give complexity results for the independent P 3-forming problem, and characterize the trees having an independent P 3-forming set.

For a graph G = (V, E), a subset S ⊆ V (G) is an equivalence dominating set if for every vertex v ∈ V (G) \ S, there exist two vertices u, w ∈ S such that the subgraph induced by {u, v, w} is a path. The equivalence domination number is the minimum cardinality of an equivalence dominating set of G, and the upper equivalence domination number is the maximum cardinality of a minimal equivalence dominating set of G. We explore relationships between total domination and equivalence domination. Then we determine the extremal graphs having large equivalence domination numbers.

For a graph G = (V, E), a subset S ⊆ V (G) is an equivalence dominating set if for every vertex v ∈ V (G) \ S, there exist two vertices u, w ∈ S such that the subgraph induced by {u, v, w} is a path. The equivalence domination number is the minimum cardinality of an equivalence dominating set of G, and the upper equivalence domination number is the maximum cardinality of a minimal equivalence dominating set of G. We explore relationships between total domination and equivalence domination. Then we determine the extremal graphs having large equivalence domination numbers.