Abstract
The invention provides an sliding contact single vane rotary vacuum pump in which an oil supply passage is placed in the centre of the rotating vane through which a lubricating oil flows, which provides oil distribution in the pump chamber with enhanced suction pressure of 39%; and the torque exertion by 2.86-7.63%, this helps in reducing the torque of the pump during maximum vacuum condition and results in reduction of the power consumption of the vacuum pump which in-turn decreases the net load on the automotive engine, thus reduces the peak torque, the pump internal chamber pressure and also results better vacuum suction performance.
Claims
1. A sliding contact single vane rotary vacuum pump (100), comprising: an open housing (1), covering the rotary vacuum pump (100) with provisions for assembling an air exit nozzle (8) and an inlet oil filter (17); a rotor (5) assembled via a coupling (6) with into the said open housing (1) having a radially movable vane (3); the vane (3) having vane slider (4A and 4B) slidably supported inside a recess of the said rotor (5); an end plate (2) to cover the said housing (1) using plurality of bolts (15), incorporating an o-ring (20) in between them to avoid any leakage; wherein, a centre relief hole (21 or 24) is provided in vane slider (4A and 4B) for oil distribution in the pump chamber with enhanced suction pressure of 39%; and the torque exertion by 2.86-7.63%.
2. The single vane rotary vacuum pump (100) as claimed in claim 1, wherein centre relief hole (21 or 24) in vane slider (4A and 4B) helps in achieving a suction pressure of 33.3 kPa in 5.18 seconds.
3. The single vane rotary vacuum pump (100) as claimed in claim 1, wherein centre relief hole (21 or 24) in vane slider (4A and 4B) exerts a torque of 0.752 N-m at 2000 RPM.
4. The single vane rotary vacuum pump (100) as claimed in claim 1, wherein plurality of oil supply passages (22 and 23) are provided within vane (3) for oil flow distribution.
5. A single vane rotary vacuum pump (100) as claimed in claim 1, wherein oil supply passages (22 and 23) within vane (3) are vertical passage, horizontal passage or any combination thereof.
6. A single vane rotary vacuum pump (100) as claimed in claim 1, wherein oil supply passages (21 and 24) within vane slider (4A and 4B) is either round hole, oblong hole, square hole or any other geometrical cavity in centre which causes the relief in pressure level.
7. A single vane rotary vacuum pump (100) as claimed in claim 1, wherein passage way (22 and 23) of vane (3) along with centre relief hole (21 or 24) in vane slider (4A and 4B) provides a channel which reduces the lubricant pressure from both the surfaces of vane (3) maintaining a steady state while operation.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] A complete understanding of the system and method of the present invention may be obtained by reference to the following drawings:
[0020] FIG. 1 is showing the torque comparison between conventional vacuum pump and one embodiment of present invention;
[0021] FIG. 2 is showing the suction performance graph between conventional vacuum pump and one embodiment of present invention;
[0022] FIG. 3 is an exploded view of one of the embodiment of present invention;
[0023] FIG. 4 is a detailed view of vane with vane slider and rotor assembly inside the pump housing in one of the embodiment of present invention;
[0024] FIGS. 5a, 5b, and 5c are detailed view of vane slider in one of the embodiment of present invention;
[0025] FIG. 6 is a detailed view of vane with vane slider and rotor assembly inside the pump housing with lubricating oil in one of the embodiment of present invention;
[0026] FIG. 7 is highlighting pressure exerted on vane with vane slider inside the pump housing by lubricating oil in one of the embodiment of present invention;
[0027] FIG. 8 is a sectional view of vane with vane slider in one of the embodiment of present invention; and
[0028] FIG. 9a, FIG. 9b and FIG. 9c are detailed view of another vane slider according to one of the embodiment of present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0029] The present invention will now be described more fully hereinafter with reference to the accompanying drawings in which a preferred embodiment of the invention is shown. This invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiment set forth herein. Rather, the embodiment is provided so that this disclosure will be thorough, and will fully convey the scope of the invention to those skilled in the art.
[0030] Now referring to FIG. 1, is a bar graph plotted for the speed (RPM) and torque. The graph provides torque comparison between conventional vacuum pump and the present invention having a single vane rotary vacuum pump with oil supply channel with relief hole in the centre. The results clearly show that more torque is generated for the same speed (RPM), clearly indicating a better performance over conventional system over wide range of RPM.
[0031] Now referring to FIG. 2, is a suction performance graph between conventional vacuum pump and the present invention having a single vane rotary vacuum pump with oil supply channel with relief hole in the centre. A graph is plotted between absolute pressure and time required to achieve the same. For consideration a set value of 33.3 kPa at 8.5 seconds is tested. During performance it is achieved by present invention in 5.18 seconds, whereas in conventional pump it is achieved in 6.6 seconds.
[0032] Now referring to FIG. 3, is an exploded view of present invention is illustrated. The vacuum pump 100 comprises of an open housing 1 inside which a coupling 6, a rotor 5, a vane 3 and vane slider 4A and 4B are secured using an end plate 2 and an o-ring 20 is placed in between them to avoid any leakage. Further open housing 1 and end plate 2 are coupled together using plurality of bolts 15. Coupling 6 and rotor 5 are coupled by mean of a locking cap 7 and screw or bolt 16. The vane 3 having vane slider 4A and 4B are slidably supported inside a recess of the rotor 5. On the open side of housing 1, a sealing o-ring 12 with external circlips 13 and 14 is provided for seal against the engine cylinder head. Further an air exit nozzle 8 is mounted with open housing 1 and a check valve arrangement made up of a valve o-ring 11, valve cover 10 and a rubber diaphragm 9 is employed inside to keep it one way. An inlet oil filter 17 is mounted on the open housing top 1 facing the engine side and is secured by using filter wire mesh 18 and circular washer 19.
[0033] Now referring to FIG. 4, is a detailed view of vane 3 with vane slider 4A and 4B and rotor 5 assemblies inside the pump open housing 1 in one of the embodiment of present invention. The vane 3 having vane slider 4A and 4B are slidably supported inside a recess of the rotor 5. The arrangement of slider 4A and 4B is such that they are always in contact with internal circumference of the pump open housing 1.
[0034] FIG. 5a, FIG. 5b and FIG. 5c are detailed view of vane slider 4A according to one of the embodiments of present invention. FIG. 5a is top view of vane slider 4A showing flat end which insert into vane recess and curved end. FIG. 5b is front view of vane slider 4A showing a centre relief hole 21 of diameter 1.5 mm. FIG. 5c is a sectional view of vane slider 4A showing through depth of centre relief hole 21.
[0035] FIG. 6 is a detailed view vane 3 with vane slider 4A and 4B and rotor 5 assemblies inside the pump housing 1 with lubricating oil inside. The vane 3 along with vane slider 4A and 4B helps in distribution of lubricating oil inside the open housing 1 and the centre relief hole 21 of vane slider 4A and 4B further reduces the oil pressure exerted on vane 3 thus helps in reducing the torque requirement for driving the pump and increases the pump vacuum efficiency.
[0036] FIG. 7 highlights pressure exerted on vane 3 with vane slider 4A and 4B inside the pump housing by lubricating oil in one of the embodiment of present invention. The centre relief hole 21 of vane slider 4A and 4B provides relief in pressure level on the vane 3 at the exit port by managing the oil flow distribution inside the pump open housing 1. This centre relief hole 21 in vane slider 4A and 4B causes decrease in the required drive torque to operate the vacuum pump 100 which results in lesser power consumption of the vacuum pump 100 by decreasing net load on automotive engine. Also the vacuum suction performance is increased and vacuum pump 100 achieves required vacuum pressure in lesser time duration which results in better vacuum suction performance.
[0037] FIG. 8 is a sectional view of vane 3 and vane slider 4A along with passage way 22 and 23 in one of the embodiment of present invention. As the oil and air mixture causes the opposite pressure forces on the vane 3 at exit port of the vacuum pump 100 which results in increase in the required drive torque to operate the vacuum pump. Centre relief hole 21 in vane slider 4A helps in oil flow distribution in the pump chamber and reduces the pump internal pressure and increases the pump vacuum efficiency. The passage way 22 and 23 along with centre relief hole 21 in vane slider 4A provides a channel which reduces the lubricant pressure from both the surfaces (upper and lower) of vane 3 thus always maintains a steady state while operation.
[0038] FIG. 9a, FIG. 9b and FIG. 9c are detailed view of another vane slider 4A in one of the embodiment of present invention. FIG. 9a is side view of vane slider 4A showing flat end which inserts into vane recess and a curved end with plurality of grooves which is in contact with internal surface of open housing 1, these slots enhance the distribution of lubricating oil while vacuum pump 100 is under operation. FIG. 9b is bottom view of vane slider 4A showing a centre relief hole 24 of diameter 1.5 mm in its centre. FIG. 9c is a sectional view of vane slider 4A showing through depth of centre relief hole 24. FIG. 9d is a side view of vane slider 4A showing plurality of grooves 25 over the curved surface of vane slider 4A.
[0039] Although the invention has been illustrated and described with respect to one or more implementations, equivalent alterations and modifications will occur. In addition, while a particular feature of the invention may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application.
[0040] Many modifications and other embodiments of the invention set forth herein will readily occur to one skilled in the art to which the invention pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
