September 28, 2018

Invention background

Publications

In this paper, the functionality of a swashplate mechanism coupled with a series of one-way overrunning clutches is studied. The novel mechanism is constructed by coupling a swashplate and one-way overrunning clutch with other mechanical components to allow producing a continuously varying gear ratio. To access the capability of the proposed mechanism, a multibody dynamic simulation of the said mechanism was carried out as follows. First, the kinematics of the components making the mechanism is studied, then followed by the dynamics of the entire system.

Preliminary predictions dictate that the proposed mechanism has the potential to produce continuously variable output motion including the zero-output using a constant input. However, the results indicate that the swashplate mechanism should be studied further to allow obtaining a smooth output. Initial results indicate that the proposed mechanism has the potential of converting a constant rotational motion to a continuously variable rotational speed.

Studying the functionality of infinitely variable drive using multibody dynamics simulation approach

This thesis work is the part of the research group working in development of new type of transmission option. The proposed Infinity Variable Drive (IVD) mechanism can be categorized as the Infinitely Variable Transmission providing continuously variable gear ratio including neutral and reverse.

The main objective of this thesis was to study the functionality of novel IVD. The new transmission system was studied using multibody dynamic simulation approach. The study was done using the multibody simulation tool MSC ADAMS 2016. The sub systems were studied separately before studying the IVD mechanism as a whole. The sub systems studied are simple planetary gear set with multiple inputs, two stage planetary gear system, and one way overrunning clutch.

The results obtained from simulation of two stage planetary gear set was verified using analytical approach. The Proof of Concept (PoC) was developed during the project and the simulation results were compared with the measurements done with the PoC.

Improvements on infinitely variable drive design

Internal combustion engines are known to have a narrow power band, a range of operating speeds under which the engine is able to operate most efficiently. In most automotive applications, the engine is accompanied by a transmission with different gear ratios to make sufficient power and torque available over the range of vehicle speeds.

Stepless, continuously variable transmissions have had the interest of inventors for centuries, but a single technically superior, cost efficient solution has not yet emerged to overtake mechanical fixed-ratio transmissions in popularity. An ideal solution would be an infinitely variable transmission, producing all the needed positive ratios, neutral and reverse without needing separate clutches.

Different friction-based and mechanical continuously variable transmissions are studied with a literature review. A novel, fully mechanical continuously variable transmission concept is introduced and then developed following the steps of VDI 2221 product development guideline. Small scale functional prototype is built and tested to study the viability of the concept.

Polttomoottori saavuttaa parhaan hyötysuhteensa kapealla kierrosnopeusalueella, minkä vuoksi sen jatkeeksi tarvitaan yleensä vaihteisto. Rajattoman määrän erilaisia välityksiä tuottavat portaattomat vaihteistot ovat kiinnostaneet keksijöitä vuosisatojen ajan, mutta yksittäistä teknisesti ylivoimaista, kustannustehokasta ja tilankäytöltään tehokasta ratkaisua ei ole vielä löytynyt. Ideaalinen ratkaisu olisi kaikkea edellä mainittua, ja tuottaisi positiivisten välitysten lisäksi myös vapaavaihteen ja peruutusvaihteen ilman erillisiä kytkimiä.

Työssä tutkitaan kirjallisuuskatsauksen omaisesti erilaisia kitkapintoihin perustuvia ja mekaanisia portaattomia vaihteistoja. Lopuksi esitellään uudenlaisen portaattoman mekaanisen vaihteiston konsepti, jota kehitetään eteenpäin VDI 2221 -tuotekehitysprosessia seuraten. Toimivuutta testataan pienoismallimittakaavan prototyypillä, jonka mittaustulokset analysoidaan. Tulosten pohjalta arvioidaan konseptin käyttökelpoisuutta.

Concept idea

 

Concept video