Properties and sizing methods of 2-motor transmissions

Authors

  • Roberto Paoluzzi C.N.R.-IMAMOTER Institute for Agricultural and Earthmoving Machines, National Research Council of Italy, Ferrara, Italy http://orcid.org/0000-0001-5857-5972
  • Luca G. Zarotti C.N.R.-IMAMOTER Institute for Agricultural and Earthmoving Machines, National Research Council of Italy, Ferrara, Italy

DOI:

https://doi.org/10.1080/14399776.2016.1234873

Keywords:

Fluid power, transmissions, off-road machines, volumetric machines

Abstract

The hydrostatic transmissions are often used to operate the drive train of off-road machines (wheeled or tracked) due to their advantages, e.g. compact size, little inertia, wide speed range, dynamic braking. Since the typical transmission with one pump and one motor (named Type A for convenience) features a rather limited application range – i.e. compatibility of specifications in terms of engine power, maximum traction and top speed – the paper reviews three improvementes to expand it without introducing too much complexity: the addition of a gearbox in series (Type B), and two alternative schemes with two motors: fixed and variable (Type C), or both variable (Type D). The constraints on size, setting and speed of the main hydraulic units dictated by each of the configurations are disclosed and their consistent design rules are discussed in detail on the basis of discrete series of heavy duty pumps and motors taken from the technical literature. To highlight the realistic implementation of the transmissions with two motors, the conventional traction vs. speed curves of three Type C and D transmissions are compared by interpolating 2-D and 3-D efficiency tables.

Downloads

Download data is not yet available.

Author Biographies

Roberto Paoluzzi, C.N.R.-IMAMOTER Institute for Agricultural and Earthmoving Machines, National Research Council of Italy, Ferrara, Italy

Roberto Paoluzzi, born in Ferrara in 1961, received the degree in Nuclear Engineering from the University of Bologna in 1986. Since 1988 he joined the Institute for Agricultural and Earthmoving Machines of the National Research Council of Italy (CNR). From 2009 until his sudden death on September 13th 2016, he was the director of the same Institute from 2002 to 2009. Main interests in the field of fluid power transmission, computational fluid dynamics and functional analysis of the safety of machinery. He is the author or co-author of over 200 scientific

Luca G. Zarotti, C.N.R.-IMAMOTER Institute for Agricultural and Earthmoving Machines, National Research Council of Italy, Ferrara, Italy

Luca G. Zarotti, born on November 20th 1945 in Parma, he received the Degree in Aeronautical Engineering at the Polytechnic Institute of Torino (1970). In 1971, he joined the Institute for Agricultural and Earthmoving Machines of the National Research Council of Italy (CNR), where he is still working. He was the director of the same Institute from 2002 to 2009. He had in charge the fluid power course at the Polytechnic Institute of Torino (from 1979 to 1982) and the University of Modena & Reggio E. (from 1996 to 1999), and the University of Ferrara (from 2002 to 2012). His research interests cover various aspects of hydrostatic locomotion, displacement control of pumps and motors, load sensing and flow sharing systems for mobile applications. Besides a number of papers and articles, he is the author of Monographs on fluid power fluids (2006), Fluid power circuits (2006 and 2010) and Hydrostatic transmissions (2010). Retired at the end of 2012, he still works on fluid power projects with the Institute as an associate researcher.

References

Dorgan, R.J. and Wallace, D.A., 1989. Dual hydrostatic drive

transmission. US patent 4848186.

Ivantysynova, M. and Weber, J., 2006. Hydrostatic multimotor

drive. US patent 2006/0162329A1.

Klaas, H., Mejia, F., and Riggenmann, F., 2012. Don’t stop –

shift on fly. Proceedings conference for mobile applications

MOBILE 2012, RE 00207/10.2012, Bosch Rexroth, Ulm,

Germany.

Kohmäscher, T., 2011. Multi-motor transmissions –

increased transmission ratio to support advanced control

systems. Proceedings 52nd national conference on fluid

power. NFPA, 113–124.

Krauss, A. and Ivantysynova, M., 2003. Control concept for a

multiple-motor type hydrostatic transmission. Proceedings

th international conference on hydraulics and pneumatics.

Prague, 183–194.

Leidinger, G., 1992. Hydrotransmatic – Ein neuartiger

stufenloser, lastschaltfreier hydrostatischer Fahrantrieb

[Hydrotransmatic - A new loss free, power shift hydrostatic

transmission]. Ölhydraulik und Pneumatik, 36, 222–232.

Marchand, D. and Morize, A., 1980. Transmissions

hydrostatiques de puissance è grande plage de fonctionnement

[Hydrostatic power transmission with large operational

rang]. EP patent 0026115A2.

Paoluzzi, R. and Zarotti, L.G., 1997. About the minimum

transmission size. In: Burrows C.R. and Edge K.A., eds.

Fluid power systems. Ninth Bath International Fluid Power

Workshop. 954-968, Bath, England: Research Studies

Press. ISBN 0863802109.

Paoluzzi, R. and Zarotti, G.L., 2013. The minimum size of

hydrostatic transmissions for locomotion. Journal of

terramechanics, 50, 153–164.

Pfordt, H., 1996. Dual hydraulic motor drive system. US

patent 5518461.

Reinecke, U. and Leidinger, G., 1992. Infinitely variable

hydrostatic transmission drive. US patent 5159992.

Renka, R.J., 1988. Multivariate interpolation of large sets of

scattered data. ACM transactions on mathematical software

(TOMS), 14, 139–148.

Rink, S., 1994. Hydraulische Antriebsysteme für

Radlader groß er Leistung, Proceedings 11th Aachener

Fluidtechnisches Kolloquium, Verein zur Förderung der

Forschung und Anwendung der Hydraulik und Pneumatik

[Hydrostatic transmission for more powerful wheel

loader] Band (2), 55–71.

Rydberg, K.-E., 1997. Hydrostatic drives in heavy mobile

machinery – new concepts and development trends. SAE

paper 981989. Warrendale, PA: Society of Automotive

Engineers.

Sannelius, M. and Palmberg, I.O., 1995. Control aspects

of hydrostatic transmissions with sequence-controlled

motors. Proceedings fourth Scandinavian international

conference on fluid power. Tampere University of

Technology, Tampere, Finland, 1073–1086.

Schubert, M., 2007. Getriebevorrichtung für ein Kraftfahrzeug

und Kraftfahrzeug [Transmission device for a motor

vehicle and motor vehicle]. EP patent 1983230A1.

Tolksdorf, D., 1993. Elektro-hydraulische Steuerung für

lastschaltbare Getriebe in Fahrzeugen [Electrohydraulic

control for variable-load motor vehicle transmission]. DE

patent 4340126A1.

Zarotti, L.G. and Paoluzzi, R., 1996. In quest of the

transmission size. Proceedings of the JFPS international

symposium on fluid power, 1996 (3), 295–300. doi:

http://dx.doi.org/10.5739/isfp.1996.295.

Downloads

Published

2017-03-01

How to Cite

Paoluzzi, R., & Zarotti, L. G. (2017). Properties and sizing methods of 2-motor transmissions. International Journal of Fluid Power, 18(1), 3–16. https://doi.org/10.1080/14399776.2016.1234873

Issue

2017: Vol 18 Iss 1

Section

Original Article