Rotary expansible chamber devices – Interengaging rotating members – Helical or herringbone
Patent
1980-05-06
1983-02-01
Vrablik, John J.
Rotary expansible chamber devices
Interengaging rotating members
Helical or herringbone
F01C 116, F01C 2112, F04C 216, F04C 1816
Patent
active
043713246
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The invention relates to a gear machine comprising two helical gears running in mesh with each other, a first sealing body coming against one end surface of the gear pair, a fluid port in the first sealing body and a second sealing body coming against the outside circles of the gears, at least at one gear meshing zone.
BACKGROUND ART
Gear pumps usually comprise two gears running in mesh with each other and arranged in a housing coming sealingly against the gears except at the gear meshing zones, the pump inlet and outlet being placed at the respective gear meshing zone.
A disadvantage with such pumps is that they deliver a pulsating flow. Furthermore, such pumps have not been able to be modified for use as supercharging compressors.
Screw pumps can be used to avoid the drawbacks just mentioned. Screw pumps can comprise two screws running in mesh with each other, the screw pair being radially, sealingly surrounded by a housing so that the pumped liquid flows "axially", i.e. along the "tooth spaces" radially sealed by the housing. The "teeth" of the screws usually extend more than one revolution round the screw body so that each "tooth" always has (for the whole of the screw revolution) at least one, and usually two, points of intermesh with its associated "tooth space".
Such screw machines are expensive to produce and do not provide complete sealing between suction and pressure sides. The high cost of the screw machine is, i.a. dependent on the difficulty of manufacturing the screw, and that the screws are usually made with different profiles.
Screw machines can be modified so that they function as supercharging compressors, e.g. by the screws being formed with diminishing pitch towards the outlet (so-called Lysholm compressors). It will however be appreciated that such modification further increases the cost of the screw machine, added to which it is usually necessary to arrange external synchronisation of the screws.
OBJECT OF THE INVENTION
One object of the invention is therefore to provide a simple gear machine comprising gears which can be produced with simple conventional gear manufacturing techniques, and thus at relatively low cost, but in spite of which have the advantages of providing substantially uniform flow, be modified simply to supercharging compressors and do not require any external synchronisation (i.e. one gear can drive the other in practice).
SUMMARY OF THE INVENTION
In accordance with the invention, this object is achieved with a machine comprises two helical gears running in mesh with each other, a first sealing body coming against one end surface of the gear pair, a fluid port in the first sealing body and a second sealing body coming against the outside diameter circles of the gears, at least at one gear meshing zone, the machine being substantially distinguished in that the tooth tops of the gears are adapted for sealing against the tooth bottoms of the gears in the plane through the axes of the gears, and that the port orifice towards the gears substantially comprises an area defined by the union of surfaces each defined by the respective tooth top circles and tooth bottom circles of the respective gear, between the axis plane and a gear radius forming an angle to the axis plane which at most attains B.times.(1/R).times.tangent .beta., where B is the width of the gear pair, R is the outside circle radius of the respective gear, and .beta. is the helix angle of the gears. Said angle of the gear radius to the axis plane is less than 2.pi.. The helix angle .beta. can be selected wth consideration to axial reaction forces and meshing friction. Each tooth preferably only extends round a portion of the circumference of the gear, e.g. about 60.degree.. An ordinary helix angle can thus be utilized, e.g. .beta.=30.degree., and the gear width B (the axial length of the gears) can be adapted to suit the gear diameter, e.g. so that the width will be substantially equal to the diameter of the gear.
If the machine is to be used as a hydraulic pump, or a hydraulic moto
REFERENCES:
patent: 2266820 (1941-12-01), Smith
patent: 2462924 (1949-03-01), Ungar
patent: 2623469 (1952-12-01), Gray
patent: 3527548 (1970-09-01), Kocher et al.
AB Bonnierforetagen
Vrablik John J.
LandOfFree
Helical gear machine with improved high pressure port does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Helical gear machine with improved high pressure port, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Helical gear machine with improved high pressure port will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2406574