Title of Invention

"IMPROVED ROTARY COMPRESSOR/PUMP"

Abstract

The invention relates to rotary compressor / pump. Elimination of discharge nonreturn valve in rotary compressor / pump improves the performance of the compressor / pump. To eliminate the discharge non-return valve the linear vane is improved into a helical vane(in shape of a rectangular section screw external thread of two turns without core, which slides in a helical slot. For a rotary ring type compressor / pump, the helical slot is provide in the cylinder and for a rotary vane type compressor / pump, the slot is provided on the shaft. The Fluid to be pumped or compressed which enters between the two turns of the helical vane through lower side of the helical vane and is trapped between sliding contacts of cylinder wall, shaft / ring and vane. As the shaft rotates in the direction of axial advance of the helical vane the fluid is pushed out through the upper side of the helical vane.

Full Text

FORM 2 THE PATENTS ACT, 1970 (39 of 1970) COMPLETE SPECIFICATION (pursuant to Section 10) Title Applicant Improved rotary compressor / pump D. PUSHPA LATHA W/0 ALAMURIMURALIDHAR 189/D, SECTOR-1 UKKUNAGARAM VISAKHAPATNAM - 530032 ANDHRA PRADESH INDIA Nationality : INDIAN The following specification particularly describes the nature of this invention an( the manner in which it is to be performed :- o Q irJ CN4 This invention relates to a rotary compressor / pump. Rotary compressor is popular for use as compressor in both refrigeration as well as air conditioning application. The main limitations of existing design of rotary compressor are the non-retum valve on the discharge port, which is provided to restrict the return of discharge side fluid entry back into the compressor and consumes considerable amomunt of energy for its operation. The other limitation is residual volume left in the compressor / pump at the end of the compression / pumping cycle and the residual volume between the compressor discharge port and non-retum valve, which makes it lesser volumetric and energy efficient. Apart from the above limitations, there is another major design limitation - the height and diameter of the compressor cylinder cannot be increased beyond certain limit, as the lubricating oil requirement increases with increase in height and diameter of the compressor cylinder, which in turn reduces the volumetric efficiency of the compressor. In the existing ring type rotary compressor / pump, the main parts are: Cylinder, Ring, Eccentric shaft and Vane. The centre of shaft coincides with the centre of cylinder. The whole assembly is placed in air tight housing and submerged in oil. When the ring is revolved by the shaft, one of its point makes continuous contact with cylinder wall. The Fluid to be pumped or compressed which enters the open space to the lower side of the vane (through the Suction port) is pushed out through the Discharge port at the upper side of the vane (considering the rotation of ring with contact point moving from discharge port to suction port through the vane). A discharge non-retum valve is provided in the discharge port to stop the return of fluid into the cylinder. In the existing vane type rotary compressor / pump, the main parts are: cylinder, shaft and vanes. The shaft has several vanes (usually even in number) which make contact with the cylinder. These vanes move in and out of slots in the shaft to make sliding contact with cylinder. The fluid to be pumped or compressed enters the open space between the vanes (through the suction port) and is pushed out through the discharge port (considering the rotation of shaft with vanes from discharge port to suction port of shorter path). A discharge non-retum valve is provided in the discharge port to stop the return of fluid into the cylinder. The objective of present invention is to propose an improved rotary compressor / pump which is so designed and adapted as to overcome the drawbacks usually encountered in existing rotary compressor / pump and also to improve its performance. In improved ring type rotary compressor / pump, the main parts are : Helical vane. Cylinder, Ring and Eccentric shaft. The centre of shaft coincides with the centre of cylinder. The helical vane is placed in the helical slot of the cylinder. The helical vane moves in and out of helical slot in the cylinder to make sliding contact with the ring. When the ring is revolved by the shaft, one of its point makes continuous line contact with cylinder wall. The Fluid to be compressed or pumped which enters between the two tums of the helical vane through lower side of the helical vane is pushed out through the upper side of the helical vane as the eccentric shaft rotates in the direction of axial advance of the helical vane. There is no requirement of discharge non-retum valve as there is no retum of the fluid back into the compression / pumping cycle of the compressor / pump and as the evacuation of compressor / pump cylinder is complete the volumetric efficiency is higher than the existmg ring type rotary compressor / pump. The lubricating oil entering the compressor / pump comes in contact all the parts of the compressor / pump by the end of compression cycle and hence lubricating oil requirement is reduced. In improved vane type rotary compressor / pump, the main parts are: vane, cylinder and shaft. The shaft has helical vane mounted on it, which makes continuous line contact with the cylinder and placed in the helical slot of the shaft. The vane moves in and out of helical slot in the shaft to make sliding contact with cylinder. The Fluid to be pumped or compressed which enters between the two tums of the helical vane through lower side of the helical vane is pushed out through the upper side of the helical vane as the shaft rotates in the direction of axial advance of the helical vane. There is no requirement of discharge non-retum valve as there is no retum of the fluid back into the compression / pumping cycle of the compressor and as the evacuation of compressor / pump cylinder is complete the volumetric efficiency is higher than the existing ring type rotary compressor /pump. The lubricating oil entering the compressor / pump comes in contact all the parts of the compressor / pump by the end of compression cycle and hence lubricating oil requirement is reduced. The invention will now be described, by way of illustration, with reference to the accompanying drawings, wherein: FIGURE -1 represents the cross section of existing rotary ring type compressor /pump; FIGURE - 2 represents the cross section of existing rotary vane type compressor / pump; FIGURE - 3 represents the cross section of improved rotary ring type compressor / pump in unassembled condition; FIGURE - 4 represents the cross section of improved rotary vane type compressor / pump in unassembled condition; FIGURE - 5 represents the cross section of improved rotary ring type compressor / pump in assembled condition; FIGURE - 6 represents the cross section of improved rotary vane type compressor / pump in assembled condition. Referring to FIGURE - 1, the main parts of rotary ring type compressor / pump are: Cylinder 102, Ring 104 mounted on Eccentric shaft 105 and a Vane 106. The centre of shaft coincides with the centre of cylinder. The whole assembly is placed in air tight housing and submerged in oil. When the ring is revolved by the shaft, one of its point makes continuous contact with cylinder wall. The Fluid 103 to be pumped or compressed which enters the open space to the lower side of the vane (through the Suction port 107) is pushed out through the Discharge port 101 at the upper side of the vane. A discharge non-retum valve 108 is provided in the discharge port to stop the return of fluid into the cylinder. The arrow on the eccentric shaft 105 indicates the direction of rotation of the eccentric shaft. Referring to FIGURE - 2, the main parts of rotary vane type compressor / pump are: cylinder 202, straight shaft 204 and vanes 205. The shaft has several vanes (usually even in number and in the figure are four in number) which make contact with the cylinder. These vanes move in and out of slots 206 in the shaft to make sliding contact with cylinder. The fluid 203 to be pumped or compressed enters the open space between the vanes (through the suction port 207) and is pushed out through the discharge port 201. A discharge non-retum valve 208 is provided in the discharge port to stop the return of fluid into the cylinder. The arrow on the shaft 204 indicates the direction of rotation of the shaft. Referring to FIGURE - 3 and FIGURE - 5, the main parts of improved rotary ring type compressor / pump are: Helical vane 301, Cylinder 302, Ring 304 and Eccentric shaft 305. The centre of shaft coincides with the centre of cylinder. The helical vane is of the shape of a rectangular section screw thread of two tums. The helical vane inner diameter is equal to the outer diameter of the ring and outer diameter is greater than the inner diameter of the cylinder. The thickness of the helical vane is equal to the width of helical slot 303 of the cylinder. The difference of outer and inner diameter of the helical vane is equal to the helical slot depth of the cylinder. The helical slot is of the shape of a rectangular section screw internal thread of two tums. The pitch of helical slot of cylinder is equal to the pitch of helical vane. The helical vane is placed in the helical slot of the cylinder, ring in the helical vane and eccentric shaft in the ring as shown in FIGURE-5. The vane moves in and out of helical slot in the cylinder to make sliding continuous contact with the ring. When the ring is revolved by the shaft, one of its point makes continuous line contact with cylinder wall and the helical vane. The Fluid 306 to be pumped or compressed which enters between the two tums of the helical vane through lower side of the helical vane is pushed out through the upper side of the helical vane as the eccentric shaft rotates in the direction of axial advance of the helical vane as indicated by the arrow 307 in FIGURE-5. At any point of time the fluid is trapped in between the tums of the helical vane, ring and line contact of ring with the cylinder. As the shaft rotates the helical vane moves in eccentricity to the helical slot of the cylinder, the fluid is pushed up wards. Referring to FIGURE - 4 and FIGURE - 6, the main parts of improved rotary vane type rotary compressor / pump are : cylinder 402, straight shaft 404 and vane 401. The centre of shaft is in eccentricity with the centre of cylinder. The helical vane is of the shape of a rectangular section external screw thread of two tums. The helical vane outer diameter is equal to the inner diameter of the cylinder and inner diameter of helical vane is less than the outer diameter of the shaft. The thickness of the helical vane is equal to the width of helical slot 403 of the shaft. The difference of outer and inner diameter of the helical vane is equal to the helical slot depth of the shaft. The helical slot is of the shape of a rectangular section internal screw thread of two turns. The pitch of helical slot of straight shaft is equal to pitch of the helical vane. The helical vane is placed in the helical slot of the shaft and shaft with helical vane is placed in the cylinder. The vane moves in and out of helical slot in the shaft to make sliding continuous contact with cylinder. When the shaft is rotated, one of its point makes continuous line contact with cylinder wall. The Fluid 405 to be compressed / pumped which enters between the two turns of the helical vane through lower side of the helical vane is pushed out through the upper side of the helical vane as the shaft rotates in the direction of axial advance of the helical vane as indicated by the arrow 406 in FIGURE-6. At any point of time the fluid is trapped in between the turns of the helical vane, ring and line contact of shaft with the cylinder. As the shaft rotates the helical vane moves in eccentricity to the helical slot of the shaft, the fluid is pushed up wards. The suction and discharge of the compressor / pump is dependent on the direction of rotation of shaft. I claim, 1. An improved rotary compressor / pump comprises of: a cylinder with helical slot, helical vane, eccentric shaft and ring for rotary ring type compressor / pump in the basic form and a cylinder, helical vane and straight shaft with helical slot for rotary vane type compressor / pump in the basic form. 2. An improved rotary compressor / pump as claimed in claim 1 contains helical vane of the shape of rectangular section screw external thread without core (appears like a square section spring) of minimum two pitch / turns. 3. An improved rotary compressor / pump as claimed in claim 1 contains helical slot of the shape of rectangular section screw internal thread of minimum two pitch / tums. 4. An improved rotary compressor / pump as claimed in claim 1 contains helical vane and helical slot of equal pitch. 5. An improved rotary compressor as claimed in claim 1 contains equal number of helical slots and helical vanes. 6. An improved rotary compressor / pump as claimed in claim 1 contain minimum one number of helical slot and minimum one number of helical vane. An improved rotary compressor / pump with more than one helical slot have multiple slots with multiple-start screw thread shape. 7. An improved rotary compressor / pump as claimed in claim 1 contains helical slot of depth equal to the difference in the outer and inner diameter of the helical vane. 8. An improved rotary compressor / pump as claimed in claim 1 contains heUcal slot of width equal to the thickness of the helical vane. 9. An improved rotary compressor / pump as claimed in claim 1 contains helical vane whose outer diameter is greater than the inner diameter of the cylinder and inner diameter equal to the outer diameter of the ring for a rotary ring type compressor. 10. An improved rotary compressor / pump as claimed in claim 1 contains helical vane whose outer diameter is equal to the inner diameter of the cylinder and inner diameter is less than the outer diameter of the shaft for a rotary vane type compressor. ►th Dated this 18th day of March 2004. (D. PUSHPA LATHA)

Documents:

252-che-2004-abstract.pdf

252-che-2004-claims duplicate.pdf

252-che-2004-claims original.pdf

252-che-2004-correspondnece-others.pdf

252-che-2004-correspondnece-po.pdf

252-che-2004-description(complete) duplicate.pdf

252-che-2004-description(complete) original.pdf

252-che-2004-drawings.pdf

252-che-2004-form 1.pdf

252-che-2004-form 13.pdf