Pumps – Expansible chamber type – Having pulsation dampening fluid receiving space
Patent
1986-08-07
1988-06-21
Vrablik, John J.
Pumps
Expansible chamber type
Having pulsation dampening fluid receiving space
418133, 418181, 418259, F04B 1100, F04C 2344, F04C 1500
Patent
active
047521953
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
This invention relates to improvements in a vane pump of a type which is generally well known in the art.
Vane types of pumps are generally provided with a pump housing and a rotor disposed between a pressure plate and a housing body, with the rotor connected to a driving shaft. The rotor has radialy displacable vanes and a surrounding cam ring. Pressure chambers and suction chambers of the pump are formed in the region between the confronting wall surfaces of the housing body and the pressure plate from which pressurized fluid in the pressure chambers is conducted to an outlet in accordance with prior art arrangements as exemplified by the disclosures in U.S. Pat. Nos. 2,357,334, 3,311,064 and 4,416,598 to Kendrick, Eichele and Merz, respectively. Such vane type pumps may also have pressure equalizing passages for the pressure chambers between the pressure plate and front wall of the housing body. The pressure equalization passages were heretofore simple, flat grooves or channels in the front wall of the housing body or in the confronting wall of the pressure plate opposite its pressure side.
Vane type pumps of the foregoing type were prone to the development of noise especially under high speed conditions mainly because of pressure pulsations. For this reason, correspondingly large pressure chambers have been proposed in order to decrease or avoid high magnitude pressure pulsations. However, such corrective measure is inconsistent with the need to construct the pump as small as possible. Further, the pressurized spaces within the pump should be made as small as possible in order to minimize internal forces.
In regard to the latter size reduction measure, the pressure collection space on the pressure side of the pump has been correspondingly enlarged so that the pressure pulsations may be reduced. However, such enlargement of the pressure collecting space is disadvantageous since it involves a significant increase in the size of the pump construction. Furthermore, the degradation of the pressure pulsations thereby achieved, is rather limited.
Therefore, an important object of the present invention is to provide a vane cell pump of the aforementioned type that is less costly to manufacture and yet avoids or largely reduces the pressure pulsations with minimal increase in size of the pump construction.
SUMMARY OF THE INVENTION
According to the invention, pressure equalization openings formed as damping chambers extend from a front wall of the housing body rearwardly. Such pressure equalization openings additionally functionn to avoid pressure pulsations.
As a result of the rearward elongation of the pressure equalizing openings in accordance with the present invention, adequate damping chamber volume is provided to serve as buffers. Since the driving shaft is mounted in the housing and must have a corresponding constructional length, the damping spaces or chambers according to the invention require no special enlargement of the housing. Rather than utilizing the pressure collecting space for damping fully developed pulsations, the damping spaces according to the present invention have the advantage of preventing development of pressure pulsations so that it will be possible to avoid such pulsations more easily than by eliminating the pulsations after they are fully developed.
There is another advantage in providing a separate damping space for each pressure chamber of the pump in accordance with the present invention. Since the damping spaces for the two pressure chambers are not connected with one another in accordance with the present invention, they do not mutually influence each other so as to avoid transmission of any pulsations therebetween as in the case of prior art arrangements.
The damping spaces may extend in an axial direction through the housing body as a result of which they are produced in a simple manner, although other arrangements are possible within the purview of the present invention. In order to obtain an optimum utilization of the available space for th
REFERENCES:
patent: 2357334 (1944-09-01), Kendrick et al.
patent: 2762312 (1956-09-01), Adams et al.
patent: 2855857 (1958-10-01), Sung
patent: 3007419 (1961-11-01), Burt
patent: 3145662 (1964-08-01), Eickmann
patent: 3233552 (1966-02-01), Kinnavy
patent: 3311064 (1967-03-01), Eichele et al.
patent: 4068987 (1978-01-01), Crooks
patent: 4416598 (1983-11-01), Merz
Friedrich Peter
Merz Johann
Vrablik John J.
Zahnradfabrik Friedrichshafen AG.
LandOfFree
Rotary vane type of pump with elongated damping chambers does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Rotary vane type of pump with elongated damping chambers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rotary vane type of pump with elongated damping chambers will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-927197