Sets Of Rollers Research Articles

Boundary control of an axially moving hybrid system of elasticity with mass-rotary rollers

In this paper, we investigate various stabilisation problems of a hybrid system of elasticity, consisting of a thin tape, which moves axially between two sets of rollers. We present a control solution, which works simultaneously, for three variants of the tape model. In particular, we design boundary feedback control laws via Lyapunov's second method. The resulting closed-loop system for the general case is then analysed, where we prove the existence and uniqueness of solution using the semigroup theory of linear operators; furthermore, we prove the exponential decay of the solution via a frequency domain theorem. The stabilisation of the two other special cases is derived implicitly from the general case proofs presented in the paper. Finally, the paper is concluded by presenting computer simulations to support the theoretical results.

Development and validation of a new artificial gastric digestive system.

The stomach is a major digestive organ of the human body that plays a role in storing, mixing, reducing chylous particles and breaking down ingested foods. This study established a new artificial gastric digestive system (AGDS) with a human stomach shape and structure by a 3D digital technology. Two sets of symmetrical rollers and one set of contrary movement of the roller were used to simulate the peristalsis of the stomach, and a pH-stat workstation was applied to control the pH. The force, pepsin and gastric juice secretion, gastric emptying and pH changes of AGDS were tacked and validated. Besides, the digestion behavior of α-lactalbumin using AGDS model, static model and semi-dynamic model (pH and enzyme changes) were studied. The results showed that the hydrolysis and morphology of protein, peptide and amino acids accumulation obtained by AGDS were different from the static digestion and semi-dynamic digestion models, indicating pH and gastric motility had certain effect on protein hydrolysis, particularly in the pepsin activity changes at early stage of digestion. AGDS, verified by mechanical analysis and in vitro digestion experiments, indicated that it can provide α-LA protein solution with a true and reliable digestion profile in the stomach, and can be used as a potential dynamic gastric digestion model for the food development.

A note on the boundary stabilization of an axially moving elastic tape

We consider a linear Euler–Bernoulli beam equation introduced by Russell (Appl Math Optim 46:291–312, 2002) that equation describes the motion of a tape moving axially between two sets of rollers. We discuss an underlying hybrid model accounting for the mass of the roller assembly and show that the system is uniformly stable; this result generalizes an earlier result by Russell and Liu (Control theory of partial differential equations, Lecture Notes Pure and Applied Mathematics, vol 242, Chapman and Hall/CRC, Boca Raton, pp 183–194, 2005), where the mass of the rollers is neglected. The proof of our well-posedness and stabilization result shows in particular that if the mass is also neglected, then no boundary controls are needed to achieve the exponential stability of the system, which improves the exponential stability result in Russell and Liu (2005) where a force control is needed.

Development of Vibrator Feeding Mechanism Using Two Sets of Rollers for the Separation of Ball Grading For Industry Benefits

The study aims to provide an Automatic Feeder Machine to inspect the Ball diameter to eliminate any parallax error and to reduce the measuring time significantly also to create an ergonomic environment for the operator. The measurement of Steel Ball diameter which is very much important needs to measure 100% before assembly. The inspection is done manually by using Micrometer which takes more time and possibility committing parallax error by operator. The micrometer needs to calibrate with master very frequently. The micrometers are normally used to measures very precision parts in rare frequency only. The possibility of mixing up rejected with acceptable items is very common in this type of inspection. The balls which are measured manually are kept separately according to the ball diameters. Due to high measurement ratio of the balls, operator by mistake passes the rejected balls in to right balls. To avoid this problem, this study focused on to develop the automatic inspection machine of vibrator feeding mechanism for balls to improve the accuracy of inspection and reduce the inspection time.

Development of Analytical Model for Dynamic Bending Force during Single Pass 3-roller Cone Frustum Bending Technique

roller conical bending process is one which is used for producing conical sections or cone frustums from metal plates for various industrial applications. The plates to be bent are cut for the required size and shape and then rolled between three cylindrical rollers. The plate is kept between one top roller and two bottom rollers. Than the top roller is lowered down and the plate gets bend. The rollers are rotated to get the roll bending of the plate. Final dimension of the cone frustum are achieved through setting appropriate machine setting parameters. An attempt is made in this paper to develop the analytical model for the prediction of the bending force during the stage of dynamic roll bending. During the roll bending of the plate there will be shear stresses along with the normal stresses. The analytical model has been developed considering these shear stresses. The model consists of various parameters like material parameters and geometrical parameters. Based on the analytical models derived, effects of some of the material parameters on dynamic bending force have been studied. In the development process complex mechanics involved in this process has been simplified so it will give insight of the process and will be helpful to the researchers and designers working in the area of metal forming, especially in roll bending process. versatility in satisfying the human needs. If there can be small reduction in cost or the increase in the effectiveness of any of the metal forming processes, it will positively affect the metal forming industry and hence the economy in the larger context. Metal forming process in which straight line of the metal is transformed into a curved length is called bending. Roll bending or Roller forming is a continuous bending operation in which a long strip of metal is passed through consecutive sets of rollers or a roller stand, each performing only an incremental part of the bend, until the desired cross sectional profile is obtained. It is observed that the roller bending process usually produces higher dimensional accuracy of the finished products (1). Conical shells and sections are also widely used in manufacturing of air duct transitions, chimneys, fan inlets, towers for wind mills, hull of ships, structural components of on shore oil and gas platforms etc. These conical shells and sections are widely used in process industries. 3-roller conical bending machines are used for production of such conical shells and sections from the metal plates. Conical bending using 3-roller bending machine can be achieved by either setting the top rollers inclined in vertical plane or setting the bottom rollers inclined in horizontal plane. Conical bending can also achieved by inclining the top roller and bottom rollers simultaneously. Bottom roller inclination significantly affects the bending moment as compared to top roller inclination during 3-roller conical bending (2) and hence, only bottom roller inclination in the horizontal plane is considered in the present analysis. In 3-roller conical bending process, the bottom rollers are inclined as shown in figure 1 and the blank is kept between the top roller and the bottom rollers such that one of the generators of the cone frustum remains parallel to the bending axis. In case of 3-roller bending machine, the bending line lies parallel to the top roller axis. The top roller is than lowered down to get the static bending of the plate. At this stage the plate gets bend locally at the bending line, kept

Mechanical and Geometrical Characterization of the Conveyors Belts from Mineral Resources Exploitation

Conveyor belt is one of the most common types of continuous handling equipment used for moving rocks of various sizes horizontally or inclined. From researches done in the exploitation of mineral resources and rocks and from the Strength of Materials calculations in this paper is observed above the conveyor sizing and other elements of the transporter requires knowing how belt traction forces (tensions thereof) varies on the conveyor length. In all cases the operation of the conveyor belt must be provided without engaging the slip phenomenon and limiting its displacement (between sets of rollers) so conveyor can operating at optimum parameters. The materials that make up a conveyor belt can be divided into two categories: materials for coating plates or outer shell and a resistance part, areas with inserts that can be textile and steel cables. Because the bands are subjected to tensile efforts and wear phenomena we determine the maximum strength they can operate without going into permanent deformation regime. Conveyor belt dimensioning calculations and other elements of a conveyor varies depending on its length and the carrier operating situations. We can see, also, that sizing conveyor belt and other conveyor components require knowledge of how belt traction forces (tensions thereof) varies along the length of the conveyor. The tensions from the conveyor belt will be study for the climb section and for the descend section. It mentions that the specific resistance to motion of the belt on full branch, consisting of resistances due: current material deformation, rotation rollers camps because pressing rubber layer and roll belt and belt bending. Since current material strength due to deformation and bending belt represents a large percentage of total specific resistance to motion, it follows that resistance decreases with decreasing displacement belt between rollers and increase with the effort in belt, respectively. This explains that resistance decreases with increasing length of conveyor (especially when its initial stretch is great), and with increasing conveyor tilt too. Also, we observe, from the values of forces calculated in the paper, that the resistance to rotation of the roller bearings decreases with increasing load on the roll, hence the values adopted for specific resistance to movement can be more larger on the empty branch than on the full. Knowing how to calculate resistances to motion of the belt, you can fix that occur belt efforts through the points made on the contour method, starting point of the drum motor development and ending point of winding it. These movement resistances calculated for empty and full branches are needed to precisely determine the installed power of the conveyor belt.

Mechanical Behaviors of HDPE Fiber Reinforced Cement Mortar

In this dissertation, we studied the mechanical behaviors of HDPE fiber reinforced in cement mortar. One of our major concerns is to study the utilization of high strength high density polyethylene (HDPE) fibers obtained from different draw ratio melt spinning processing. Another major concern is to compare these fibers in term of mechanical behavior reinforced in cement mortar. We began with the material characterization, which mainly include different draw ratios with two sets of rollers through a glyceral bath set at 113°C. Draw ratio was calculated from the ratio of the speed of the follower to leader roller. The latter studies largely used three different fiber volumes fraction ratio tested mechanical properties of cement mortar by using the universal testing machine follow on ASTM standard testing. Subsequently, we studied the behaviors of HDPE fiber reinforced in cement mortar, which mainly include the flexural, tensile and compression strength. The development of mechanical strength of cement mortar when added with these fibers were presented characterize of cement mortar.

Load Distribution of Cross-Roller Slewing Bearing

Because of cross roller-slewing bearing structure have a certain degree of particularity, and two sets of cross rollers is equivalent to two columns roller stack situation, therefore it should deduce roller calculation formula for two sets of roller respectively. According to the stress of the slewing bearings, we proceed load distribution calculation synthetically under the center of bearing axial force, overturning moment and radial force. Finally, based on the above formula for calculating the bearing load distribution and through the Matlab software, we analyze the influence of some parameters on the bearing load distribution. For ensuring bearing design parameter, it has the certain reference value.

Effects of directed movement of fibres in a twist triangle on yarn quality

This work investigates the effect of directed flow of the fibres in a twist triangle on yarn properties. This is done using different clip‐on attachments positioned on the front rollers of a ring spinning frame. Seven sets of rollers (plain non‐grooved; 75°‐biased left‐to‐right grooved; 75°‐biased right‐to‐left grooved; 15°‐, 45°‐ and 75°‐biased grooved from both sides towards the centre and solo) are made and positioned immediately below and parallel to the top front draft rollers of the laboratory ring spinning frame (tester model 82 KA) so that they can interact with the emerging drafted fibre strand before twist insertion. Afterwards, a 0.495‐ktex (2.02 Nm) finisher worsted roving composed of 55% polyester and 45% wool is fed into each unit of the ring spinning frame to produce a yarn with a yarn count of 30 Nm and a twist factor of 125. The rollers affect the flow of the fibres in the triangle zone and, as a result, the quality of the yarns is affected. A comparison of the yarns produced shows that directing the fibres in the triangle zone could improve the yarn quality. The results indicate that the 75°‐biased grooved (from both sides towards the centre) rollers improve the yarn quality in terms of hairiness, elongation and imperfections.

单轴柔性铰链柔度系数试验装置的设计

To obtain the test data from the experimental research on the compliance factors of the flexure support structure of a large scale reflector used in an airborne image sensor,a compact single-axis flexure hinge experimental setup was proposed and designed.By using this experimental setup,end-bending and pure moment bending experiments of the single-axis flexure hinge could be achieved on a common single-axis Material Testing System(MTS).This setup utilizes the leverage principle to realize the pure moment loading on the single-axis MTS and takes the side constraint configuration which is composed of several sets of rigid rollers to constrain the pure moment loading sub-assembly.By these ways,the effect of the friction on the load transmission was reduced greatly.Furthermore,the virtual simulation of the pure moment bending process was performed.It indicates that the side force stemmed from the constraint of L pushing component is the main influence factor on the bending processing,and the maximum side force can be controlled at 4.783 N.In order to verify the test data,Finite Element Analysis(FEA) and theoretical calculation were employed.The comparison shows that the test results are concident with FEA results and theoretical results well,and test results and theoretical results are slightly smaller than FEA results.Compared with FEA,the maximum relative error of the test data is only 3.87%,which indicates that this experimental setup is a good solution for study of flexure support structures used in optical reflectors.

S1101-2-3 歯車の伝達効率に及ぼす潤滑油組成の影響 : 第2報, 4円筒試験機によるトラクション特性(伝動装置の基礎と応用セッション2)

In order to clarify influence of the lubricant composition on the transmission efficiency of the helical gear for vehicles driven at high speed and low load conditions, traction measurement of lubricants was conducted using a Four-roller tester. As a result of the measurement using three sets of rollers with which surface roughness differs, when the surface roughness was smaller, the difference in the traction coefficient between commercial ATF and traction oil KTF-1 was larger. On the other hand, the difference was smaller when the surface roughness was larger. The surface roughness of the test gear was almost same as that of the latter case, and there was a good correlation between the average traction coefficient obtained in the case of rougher test rollers and gear power losses which is mainly caused by meshing lose.

A Study on the Contact Behaviors of Infinitely Variable Transmission System with Full Toroidal Shapes of Disks

The torque of the continuously variable transmission system with friction drive mechanism is transmitted by contacting roller with input and output disks. For the higher transmitted torque, it is necessary to apply large load in order to get higher friction force, which in turn generates severe high stress on the contact surfaces of roller and disks. The toroidal type CVT system has simple component arrays that have three contact points between roller and each input or output disk to get the torque transmitted. However, compact assembly design of the three sets of rollers contacting with input and output disks needs the roller to stay with unsymmetrical angled position with each other. Therefore, the contact shapes between roller and disk vary according to the transmission ratio and should be investigated to avoid the excessive contact stress over than ~1.8 GPa. In this study, the contact geometries of roller and disks in the toroidal type CVT system are computed during the gear ratios. The contact area of which the size depends on the material elasticity, curvatures of roller and disk, and applied load are all of elliptic shapes because of the convex and concave curvatures of roller and disk shapes, respectively. From the computed results considering the size of roller diameter, roller stroke and applied load, it is found that the shapes of contact area changes the sizes of major and minor elliptical diameters in the rolling direction during the gear ratios due to the unsymmetrical angled position of roller.

Improvements to the wet spinning of flax: Part I – the effect of two sets of feed rollers on the physical characteristics of wet spun linen yarns

This paper investigates the influence of the two sets of feed rollers prior to roller drafting on the physical properties of wet spun linen yarns, such as tensile properties and yarn regularity. The effect of using either a single or double set of feed rollers on the fibre fineness distribution of bleached rove was quantified using the Sirolan TM Laserscan system and reported in terms of mean fibre fineness and percentage of fibre having a diameter above 30.5 microns. Comparative spinning trials using either one or two sets of in-line feed rollers were undertaken with several batches of bleached rove. The effect of spinning parameters on tensile and regularity characteristics of the spun yarns are reported and discussed. The effect of open reach as control parameter in double feed roller spinning was also investigated. Wet spun linen yarns produced via the double crushing of bleached rove with two sets of consecutive feed rollers have a higher mean tenacity than the traditional single roller feed system.

Low noise burster

A burster for separating successive sheets of paper from a continuous web of paper has at least one output or draw roller having a larger diameter than the input or feed rollers with all of these rollers rotated at the same r.p.m. and a simple belt drive mounted on a pivotal double link with a one-to-one ratio provides for driving one set of rollers from the other set with an adjustable distance between sets of rollers.

Noise-absorbing bar stock guide for screw machine

The present arrangement for guiding bar stock being fed to a screw machine has yieldably-mounted rollers which project into a rotatable guide tube to guide the rotatable bar stock between them. The yieldable, resilient mounting of these rollers substantially eliminates noise and absorbs the transverse forces acting on the bar stock. Preferably, several sets of such rollers are provided at different locations along the length of the guide tube.

二重ベルトによる単一物の挟み込み実験

A vertical double-belt conveyor conveys material by holding it between two belts. The magnitude of theholding force depends on such parameters as the belt tension, the idler arrangement and the mechanical characteristicsof the belt.This paper deals with experimental investigations carried out to reveal the relations between themagnitude of the holding force and such parameters.First, tensile tests of the belt are carried out to identify its mechanical characteristics. Theresults of the tensile tests are as follows;1) From the rhoeological point of view, the belt can be described as a 3-element solid.2) From the point of view of anisotropic elasticity, the belt can be regarded as orthotropic.Second, the holding force is measured under various conditions on an experimental stand. The stand hasfour sets of carrier rollers and a pair of belts (double-belts) to simulate the straight part of a vertical double-beltconveyor. Between the double-belts are held small rings (2cmφ) on which strain gages are stuck to show the holding force.The main results are as follows:1) The holding force increases with the increase of the belt tension.2) The holding force becomes quite large when the ring comes to just onto an idler.3) The relation between the holding force and the degree of offset of the idlers depends on the troughangle.4) The holding force decreases with the increase of the trough angle.