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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Utveckling av hjullastarkranarm

Killberg, Linus January 2016 (has links)
No description available.
2

Förmontering av lyftramverk

Olsson, Erik, Jonsson, Christian January 2007 (has links)
<p>Volvo Hauler & Loader Division in Arvika produces wheel loaders which they deliver</p><p>throughout the world. The factory which is situated in Arvika is the largest wheel loader plant in the whole world, with its 1 100 employees. The different models stretch from L60E all the</p><p>way up to the brand new L350F, with a loader capacity from six tons up to a staggering 35.</p><p>The assembly of the different models are divided into three different assembly lines, Small</p><p>(L60-L90), Medium (L110-L120) and Large (L150-L220). The assembly of Heavy (L350)has just been started with an upcoming pre series.</p><p>This examination paper gives recommendations of improvements and necessary modifications to rationalize the pre-assembly of boom units. Three different scenarios are presented in the paper. One scenario, where the work-station resembles the current workstation,</p><p>but with a improved layout and safer working environment.</p><p>The second scenario states a working-station where fully pre-mounted boom units should be produced, although this station requires some alterations in the construction which are mentioned in the paper.</p><p>The last scenario is a vision of the future, where all three lines are gathered into one big line, accordingly with the visions of the company outline.</p>
3

Utveckling av en fördelningsväxellåda till hjullastare

Franzén, Tony, Ekberg, Daniel January 2019 (has links)
The thesis is a case study on the construction of a dropbox for wheel loaders. The thesis was carried out at Volvo Construction Equipment (VCE) who is one of the leading manufacturers of construction equipment. The data collection consisted of a pre-study, a literature review, and simulations and calculations, which was done at VCE. This led to the use of both primary and secondary data, as well as quantitative and qualitative data. The purpose of the thesis was to construct a dropbox which could be combined with a gearbox, for it to work in a wheel loader. The gearbox was a planetary gearbox used in articulated haulers and only some smaller adjustments were to be made on the gearbox. Part of the thesis was to investigate the possibilities to use a hydraulic or electric system in combination with the dropbox. This was to improve the fit of the planetary gearbox to the wheel loader and possibly improve the environmental impact from the wheel loader. The research questions in the thesis were: F1: How can a dropbox be constructed to enable a gearbox fitted for articulated haulers to work in wheel loaders? F2: What are the possibilities to affect the overall cost of the transmission and the environmental impact of the wheel loader with the construction of a dropbox? F3: Which outcomes regarding manufacturing and sales would occur when a articulated hauler and a wheel loader uses the same planetary gearbox? F4: What general factors can be identified to make a modular completion of a existing gearbox, to create a gearbox for better manufacturing and aftermarket management? The method that was used was a combination of Ullman’s and Ulrich and Eppinger’s product development processes. The work was divided in four general phases: planning, information gathering, concept generation, and further development. Appropriate techniques were used to ensure that every phase was completed. The result was a suggestion of a construction of a dropbox. This dropbox was to be combined with a planetary gearbox for articulated haulers to be adjusted to fit the wheel loader model L350. Six gears were chosen from the planetary gearbox for driving both forward and backward. The construction of the dropbox consisted of a cog chain which distributes the driving force and shift elements which changes the direction. The energy which the shift elements were to dissipate was calculated and the dimensions of the cogwheels in the cog chain were estimated. A CAD-model was made to generate an image of the concept. Important factors for the conclusive result included which gears that was used and how they were used. This is a result of the different driving cycles the working machines have, since the driveline has to be adjusted for every machine. A complementary system was an important factor regarding cost and environmental impact. However, it was shown to be hard to implement because of the wide range of the rotational speed in which the complementary motor had to work. Further investigations are required regarding the choice of torque converter, construction of power take-out for the work hydraulic, integration of a complementary system, and the construction of the dropbox case. / Examensarbetet är en fallstudie på konstruktionen av fördelningsväxellåda till hjullastare. Examensarbetet utfördes hos uppdragsgivaren Volvo Construction Equipment (VCE) som är ledande inom tillverkningen av entreprenadmaskiner. Datainsamlingen bestod av en förstudie, en litteraturstudie samt simuleringar och beräkningar som genomfördes på VCE. I och med detta har både primärdata och sekundärdata, samt kvalitativa och kvantitativa data, använts. Syftet med arbetet var att konstruera en fördelningsväxellåda som kunde kombineras med en antagen växellåda för att fungera i en hjullastare. Den antagna växellådan var av planetväxeltyp anpassad för dumprar och mindre ändringar på växellådan fick genomföras. I arbetet ingick även att undersöka möjligheterna att använda hydraul- eller elsystem i kombination med fördelningsväxellådan. Detta för att förbättra anpassningen av planetväxellådan samt möjligtvis förbättra miljöpåverkan från hjullastaren. De forskningsfrågor som ställdes upp var följande: F1: Hur kan en fördelningsväxellåda konstrueras för att möjliggöra att en växellåda primärt anpassad för dumprar ska fungera för hjullastare? F2: Vilka möjligheter finns att påverka kostnaden för transmissionen och miljöpåverkan från hjullastaren när en fördelningsväxellåda konstrueras? F3: Vilka utfall kring tillverkning och försäljning skulle uppstå då en dumper samt hjullastare nyttjar samma planetväxellåda? F4: Vilka generella faktorer kan identifieras om man vill göra en modulär komplettering av en existerande växellåda, för att skapa en växellåda för bättre produktion samt för hantering av eftermarknad? Den metod som valdes var en kombination av Ullmans och Ulrich och Eppingers produktutvecklingsprocesser. Arbetet delades in i fyra övergripande faser: planering, informationsinsamling, konceptgenerering och vidareutveckling. I dessa faser användes lämpliga tekniker för att kunna säkerställa att varje fas avklarades. Arbetet resulterade i ett förslag till en konstruktion av en fördelningsväxellåda. Denna fördelningsväxellåda skulle kombineras med en planetväxellåda för dumprar för att kunna passa en hjullastare av modell L350. Sex växlar valdes ifrån planetväxellådan för både framåtoch bakåtkörning. Konstruktionen av fördelningsväxellådan bestod av en kuggkedja som sköter fördelningen av drivkraften samt skiftelement som vänder riktning. Energin som skiftelementen skulle ta upp beräknades fram och storlekarna för kugghjulen i kuggkedjan uppskattades. En CAD-modell skapades för att kunna generera en bild över konceptet. Viktiga faktorer för det slutgiltiga resultatet inkluderade vilka växlar som används samt hur de används. Detta eftersom entreprenadmaskinerna har olika körcykler där drivlinan måste anpassas efter varje entreprenadmaskin. Ett kompletterande system var en viktig faktor med hänsyn till kostnad och miljöpåverkan. Dock visade det sig att kompletterande system var svårhanterat på grund av de varvtalsområden som den kompletterande motorn behöver arbeta med. Vidare undersökningar bör göras för val av momentomvandlare, konstruktion av uttag för arbetshydraulik, integrering av ett kompletterande system och konstruktionen av fördelningsväxellådshuset.
4

Vidareutveckling av häftfixtur för sammansvetsning av Volvo hjullastares lyftramverk : Ett projekt med syfte att effektivisera produktionen / Further development of a welding fixture for assembling booms for Volvo wheel loaders : A project with the aim to increase the production efficiency

Ejnermark, Caroline January 2013 (has links)
No description available.
5

Vehicle dynamic analysis of wheel loaders with suspended axles

Rehnberg, Adam January 2008 (has links)
<p>The wheel loader is a type of engineering vehicle used primarily to move crude material over shorter distances. As the vehicle is designed without wheel suspension, wheel loader drivers are exposed to high levels of whole body vibration which influences ride comfort negatively. The work presented in this thesis has the aim to investigate the potential in adding an axle suspension to a wheel loader in order to reduce vibrations and increase handling quality. While suspended axles have great potential for improving ride comfort and performance, they will also necessarily affect the vehicle dynamic behaviour which is different in many aspects from that of passenger cars or other road vehicles: the wheel loader has a large pitch inertia compared to its mass, the axle loads vary considerably with loading condition, and the vehicle uses an articulated frame steering system rather than wheel steering. These issues must all be considered in the design process for a wheel loader suspension.</p><p>The effects of suspended axles on ride vibrations are analysed by simulating a multibody wheel loader model with and without axle suspension. Results from the simulations show that longitudinal and vertical acceleration levels are greatly reduced with axle suspension, but that the decrease in lateral acceleration is smaller. By reducing the roll stiffness lateral accelerations can be further reduced, although this may not be feasible because of requirements on handling stability. The pitching oscillation of the vehicle has also been studied as this is known to have a large influence on ride comfort. An analytical model is used to study the effect of front and rear suspension characteristics on the pitching response of the wheel loader, showing that a stiffer rear suspension is favourable for reducing pitching but also that a similar effect is attainable with a stiffer front suspension. Results are compared to multibody simulations which show the same trend as analytical predictions. By including a linearised representation of a hydropneumatic suspension in the models, it is also shown that favourable dynamic behaviour can be maintained when the vehicle is loaded by utilising the fact that suspension stiffness is increasing with axle load.</p><p>Articulated vehicles may exhibit lateral oscillations known as "snaking" when driven at high speed. The effect of suspended axles on these oscillations are analysed using a multibody simulation model of a wheel loader with an equivalent roll stiffness suspension model. It is found that the roll motion of the sprung mass has a slightly destabilising effect on the snaking oscillations. This effect is more pronounced if the body roll frequency is close to the frequency of the snaking motion, although this loss in stability can be compensated for by increasing the equivalent stiffness or damping of the steering system.</p><p>Together with existing vehicle dynamic theory and design rules, the studies reported in this work provide an insight into the specific issues related to suspension design for wheel loaders.</p>
6

Förmontering av lyftramverk

Olsson, Erik, Jonsson, Christian January 2007 (has links)
Volvo Hauler &amp; Loader Division in Arvika produces wheel loaders which they deliver throughout the world. The factory which is situated in Arvika is the largest wheel loader plant in the whole world, with its 1 100 employees. The different models stretch from L60E all the way up to the brand new L350F, with a loader capacity from six tons up to a staggering 35. The assembly of the different models are divided into three different assembly lines, Small (L60-L90), Medium (L110-L120) and Large (L150-L220). The assembly of Heavy (L350)has just been started with an upcoming pre series. This examination paper gives recommendations of improvements and necessary modifications to rationalize the pre-assembly of boom units. Three different scenarios are presented in the paper. One scenario, where the work-station resembles the current workstation, but with a improved layout and safer working environment. The second scenario states a working-station where fully pre-mounted boom units should be produced, although this station requires some alterations in the construction which are mentioned in the paper. The last scenario is a vision of the future, where all three lines are gathered into one big line, accordingly with the visions of the company outline.
7

Vehicle dynamic analysis of wheel loaders with suspended axles

Rehnberg, Adam January 2008 (has links)
The wheel loader is a type of engineering vehicle used primarily to move crude material over shorter distances. As the vehicle is designed without wheel suspension, wheel loader drivers are exposed to high levels of whole body vibration which influences ride comfort negatively. The work presented in this thesis has the aim to investigate the potential in adding an axle suspension to a wheel loader in order to reduce vibrations and increase handling quality. While suspended axles have great potential for improving ride comfort and performance, they will also necessarily affect the vehicle dynamic behaviour which is different in many aspects from that of passenger cars or other road vehicles: the wheel loader has a large pitch inertia compared to its mass, the axle loads vary considerably with loading condition, and the vehicle uses an articulated frame steering system rather than wheel steering. These issues must all be considered in the design process for a wheel loader suspension. The effects of suspended axles on ride vibrations are analysed by simulating a multibody wheel loader model with and without axle suspension. Results from the simulations show that longitudinal and vertical acceleration levels are greatly reduced with axle suspension, but that the decrease in lateral acceleration is smaller. By reducing the roll stiffness lateral accelerations can be further reduced, although this may not be feasible because of requirements on handling stability. The pitching oscillation of the vehicle has also been studied as this is known to have a large influence on ride comfort. An analytical model is used to study the effect of front and rear suspension characteristics on the pitching response of the wheel loader, showing that a stiffer rear suspension is favourable for reducing pitching but also that a similar effect is attainable with a stiffer front suspension. Results are compared to multibody simulations which show the same trend as analytical predictions. By including a linearised representation of a hydropneumatic suspension in the models, it is also shown that favourable dynamic behaviour can be maintained when the vehicle is loaded by utilising the fact that suspension stiffness is increasing with axle load. Articulated vehicles may exhibit lateral oscillations known as "snaking" when driven at high speed. The effect of suspended axles on these oscillations are analysed using a multibody simulation model of a wheel loader with an equivalent roll stiffness suspension model. It is found that the roll motion of the sprung mass has a slightly destabilising effect on the snaking oscillations. This effect is more pronounced if the body roll frequency is close to the frequency of the snaking motion, although this loss in stability can be compensated for by increasing the equivalent stiffness or damping of the steering system. Together with existing vehicle dynamic theory and design rules, the studies reported in this work provide an insight into the specific issues related to suspension design for wheel loaders. / QC 20101119
8

Körbarhetskvantifiering av Hjullastare

Stener, Patrik, Snabb, Robert January 2008 (has links)
<p>Idag är det möjligt att modellera de hydrauliska och mekaniska systemen hos en hjullastare. Det går även i viss omfattning att simulera omgivningen samt de förarkommandon som krävs för utförandet av en önskad uppgift. Däremot är det enda sättet att få reda på hur en förare kommer att uppleva maskinen, dess körbarhet, att bygga en fungerande prototyp och be en förare att testa den.</p><p>Syftet med det här examensarbetet var att hitta en korrelation mellan förarens bedömningar och mätdata insamlade från en hjullastare under körning. Resultaten är sedan tänkta att användas i framtida simuleringar. Olika hjullastare testades av en grupp provförare och deras subjektiva bedömningar såväl som mätdata från hjullastarna samlades in.</p><p>Slutsatsen är att det går till en viss del att förutsäga körbarheten från insamlade data om förarens körstil är känd. Då förarnas körstil skiljer väldigt mycket är det är inte möjligt att dra allmänna slutsatser om körbarheten.</p> / <p>Today it is possible to model all hydraulic and mechanical systems of a wheel loader. To an extent the surrounding environment and the operator input required for a desired operation can also be simulated. However the only way to determine how an operator will perceive the handling qualities, the operability, of the wheel loader is to assemble a working prototype and ask an operator to try it out.</p><p>The purpose of this Master thesis was to find some correlation between the drivers’ opinions and data recorded from the machines during operation. The results are intended to be used in future simulations. Different machines were tested by a group of drivers and their subjective impressions, as well as measurements from the machines were collected.</p><p>The findings from the analysis are that the operability can be determined to a certain extent if the driver’s behaviour is known. Because of the differences in the way the drivers operate the machine it has not been possible to draw any general conclusions.</p>
9

Körbarhetskvantifiering av Hjullastare

Stener, Patrik, Snabb, Robert January 2008 (has links)
Idag är det möjligt att modellera de hydrauliska och mekaniska systemen hos en hjullastare. Det går även i viss omfattning att simulera omgivningen samt de förarkommandon som krävs för utförandet av en önskad uppgift. Däremot är det enda sättet att få reda på hur en förare kommer att uppleva maskinen, dess körbarhet, att bygga en fungerande prototyp och be en förare att testa den. Syftet med det här examensarbetet var att hitta en korrelation mellan förarens bedömningar och mätdata insamlade från en hjullastare under körning. Resultaten är sedan tänkta att användas i framtida simuleringar. Olika hjullastare testades av en grupp provförare och deras subjektiva bedömningar såväl som mätdata från hjullastarna samlades in. Slutsatsen är att det går till en viss del att förutsäga körbarheten från insamlade data om förarens körstil är känd. Då förarnas körstil skiljer väldigt mycket är det är inte möjligt att dra allmänna slutsatser om körbarheten. / Today it is possible to model all hydraulic and mechanical systems of a wheel loader. To an extent the surrounding environment and the operator input required for a desired operation can also be simulated. However the only way to determine how an operator will perceive the handling qualities, the operability, of the wheel loader is to assemble a working prototype and ask an operator to try it out. The purpose of this Master thesis was to find some correlation between the drivers’ opinions and data recorded from the machines during operation. The results are intended to be used in future simulations. Different machines were tested by a group of drivers and their subjective impressions, as well as measurements from the machines were collected. The findings from the analysis are that the operability can be determined to a certain extent if the driver’s behaviour is known. Because of the differences in the way the drivers operate the machine it has not been possible to draw any general conclusions.
10

Taktningsutrustning till Ljungbymaskin

Persson, Philip, Andersson, Ludvig January 2017 (has links)
This bachelor thesis was made on behalf from the wheel load maker Ljungby Maskin AB. Ljungby Maskin is right now in an expansive stage with a development of the welding workshop and the paint shop. In relationship to this they are also changing from station assembly to production line. Because of the progress they have needs of some type of transport method. The first step of the project was to decide what method that should be used. Rune Andersson, one of the supervisors in the project was at first into using air caster/air bearings to transport the production. However after some research the result was that air caster wasn’t the best method to use.  To make this conclusion a visit at Atlas Copco was made to see their production lines and a discussion with the production developer at AC was made. After the method was decided, the design of the fixtures could be made. The method to make the design was principle and primary design by Fredy Olsson. The output from this gave in total 12 different constructions. Pugh-matrix was made at the different constructions to be sure which one that should be used.  Complete CAD-models were made for the constructions that got the highest mark. Through a product draft it was determined which details that should been bought and which should be self-designed. Complete detail constructions were made at these parts. To ensure the strength of the parts, FEM-analysis was made in CATIA V5. The conclusion was that the project will be a good support in the development of the new assembly workshop at Ljungby Maskin AB and that it will contribute to a smaller storage and increase the production. / Examensarbetet har gjorts på uppdrag av Hjullastartillverkaren Ljungby Maskin AB. Ljungby Maskin är just nu i en expansiv fas med utbyggnad av bland annat svetsverkstad och lackering. I samband med detta skall de även byta från stationsmontering till produktionslina. Det finns då behov av någon typ av transportmetod för att förflytta hjullastarna. Första steget i projektet var att bestämma vilken typ av flyttmetod som ska användas. Rune Andersson en av handledarna vid Ljungby Maskin, var från början inne på att använda luftkuddar som flyttmetod. Efter att bakrundstudien var gjord visade det sig att detta inte var den metod som lämpade sig bäst för detta projekt.  För att komma fram till detta gjordes bland annat ett studiebesök på Atlas Copco där granskade deras produktionslinor och diskussion fördes med deras produktionsutvecklare.  När transportmetoden var bestämd konstruerades fixturerna utifrån detta. Metoderna som då användes var framför allt Fredy Olssons Princip- och Primärkonstruktion. Detta resulterade i totalt 12 olika konstruktioner. Pugh-matriser gjordes på de olika konstruktionerna för att konstatera vilka konstruktioner som skulle användas. Fullständiga CAD-modeller togs fram på de konstruktioner som fått högst betyg. Via produktutkast bestämdes det vilka delar som skulle köpas in samt konstrueras själva. Kompletta detaljkonstruktioner gjordes på dessa delar. För att säkerställa detaljernas hållfasthet gjordes FEM-analyser i CATIA V5. Slutsaten blev att projektet kommer vara ett bra underlag i Ljungby Maskins utveckling av den nya monteringen och bidra till att kunna minska lagret samt öka produktionen.

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