US3706514A - Inner seal assembly for rotary mechanisms - Google Patents
Inner seal assembly for rotary mechanisms Download PDFInfo
- Publication number
- US3706514A US3706514A US179059A US3706514DA US3706514A US 3706514 A US3706514 A US 3706514A US 179059 A US179059 A US 179059A US 3706514D A US3706514D A US 3706514DA US 3706514 A US3706514 A US 3706514A
- Authority
- US
- United States
- Prior art keywords
- ring
- seal
- rotor
- support ring
- axially extending
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
- F01C19/00—Sealing arrangements in rotary-piston machines or engines
- F01C19/10—Sealings for working fluids between radially and axially movable parts
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
- F01C19/00—Sealing arrangements in rotary-piston machines or engines
- F01C19/12—Sealing arrangements in rotary-piston machines or engines for other than working fluid
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16J—PISTONS; CYLINDERS; SEALINGS
- F16J15/00—Sealings
- F16J15/16—Sealings between relatively-moving surfaces
- F16J15/34—Sealings between relatively-moving surfaces with slip-ring pressed against a more or less radial face on one member
Definitions
- the inner seal assembly for rotary mechanisms having a rotor mounted within a housing for rotation on an eccentric of a crankshaft comprises a seal-ring interconnected with a support ring for conjoined rotation and limited axial movement relative to each other and a biasing means disposed between the two' rings for urging the rings to separate.
- a resilient seal means is carried by the outer peripheral portion of the sealring.
- the unitary inner seal assembly is positioned in a recess defined by a peripheral step in a disk attached to the crankshaft and an annular, axially extending wall formed in the rotor so that the seal-ring is in sea]- ABSTRACT ing abutment against the radial wall of the peripheral step while the resilient seal-means seals the interstices between the axially extending wall of the rotor and the periphery of the disk.
- the support ring and rotor are constructed and arranged to interconnect and thereby provide conjoined rotation of the inner seal assembly and rotor.
- the invention relates to seals for rotary mechanisms and, more particularly, to an inner seal assembly for such mechanisms.
- the rotary mechanisms contemplated herein may be of the type shown in U.S. Pat. No. 2,988,065, issued to Felix Wankel et al. on June 13, 1961.
- the rotary mechanisms of the type to which the present invention is applicable normally comprise an outer body or housing and an inner body or rotor eccentrically mounted on a crankshaft for rotation in the housing.
- the outer peripheral surface of the rotor and the adjacent housing walls define a plurality of working chambers which, during relative rotation of the rotor, vary in volume.
- the chambers are preferably sealed from one another by sea] means disposed between the rotor and housing. It has been common practice, as exemplified in the United States patents to Wenderoth et al., U.S. Pat. No. 3,323,713, Jungbluth, No.
- the aforementioned inner seal-rings are effective only when a predetermined pressure in the liquid in the rotor is maintained to bias the rings axiallyinto abutment against the groove walls. Obviously, when the mechanism is not operating, the predetermined differential fluid pressure across the rings does not exist and, therefore, a positive seal is not achieved.
- a seal-ring is provided which surrounds the inner seal assembly to provide a seal when the engine is at a standstill. This supplemental seal, however, becomes ineffective when the engine is operating because the seal is forced out of contact with the sealing surface by the liquid pressure generated when the engine is running.
- an object of this invention to provide an inner seal assembly that is capable of providing an effective seal during high speed operation of the mechanism as well as when the mechanism is at a standstill.
- a further object of this invention is to provide an inner seal assembly having a seal-ring and a coacting O- ring in which wear of the O-ring is obviated.
- the 'A feature of the present invention is the capability of preassembling the inner seal assembly and thereby being able to quickly and easily position it in an annular space defined by a peripheral groove formed in a disk secured to the crankshaft and an adjacent, axially extending annular wall of the rotor.
- the assembly is constructed of a seal-ring, a support ring interlocking with the sealring in such a manner as to allow limited relative axial movement between the two rings, and a biasing means disposed between the seal-ring and support ring to urge the two rings apart in an axial direction.
- the assembly also includes a resilient annular 'seal means carried by the seal-ring.
- the sealring sealing abuts a radially extending wall of the disk under the urging of the biasing means while the resilient, annular, seal means seals the interstices between the seal-ring and the axially extending, annular wall of the rotor.
- Another feature of this invention is the means for connecting the inner seal assembly with the member against which the resilient, annular seal means abuts so that the assembly rotates with such member to obviate frictional wear of the seal means.
- the invention contemplates a novel inner seal assembly comprising a seal-ring, a support ring interconnected with the seal-ring so as to provide for their conjoined rotation and permit limited relative axial movement between the two rings.
- a biasing means which may be in the form of a wavy washer, is disposed in an annular pocket defined between the seal-ring and the support ring to urge the two rings apart to the limit of relative axial movement in that direction.
- a resilient seal means carried by the seal-ring completes the unitary inner seal assembly.
- the components of the inner seal assembly are dimensioned so that in an axial direction it is slightly larger than the space defined by the peripheral step in the disk and the surface of the housing end wall of the mechanism so that the support ring and the seal-ring are resiliently urged in abutment by the biasing means against the said surface of the housing end wall and the radially extending step of the disk, the resilient annular seal means being in abutment against an axially extending surface fonned on the rotor of the rotary mechanism.
- the inner seal assembly is connected to the rotor for conjoined rotation therewith so that there is no frictional wear on the resilient seal means bearing against the axially extending surface of the rotor.
- a bearing surface of a material having a low coefficient of friction be provided between the abutting surfaces of the seal-ring and the radial surface of the disk.
- the low friction material may be in the form of a ring of carbon or other non-metallic material having self-lubricating characteristics, such as polytetrafluoroethylene, inserted in the seal-ring or in the disk.
- a low friction material be interposed between the abutting surfaces of the resilient seal means and the axially extending, annular surface of the rotor.
- This material of a low coefficient of friction may be coated on the resilient seal means or the aforementioned annular, axially extending surface of the rotor. This minimizes the distortion or stress which tends to be imposed on the resilient seal means when the inner seal assembly moves slightly axially as the rotor and the disk, carried by the eccentric crankshaft, move axially relative to each other.
- the inner seal assembly may comprise an annular membrane which, along its inner peripheral portion, is
- the inner seal assembly may comprise, in place of the resilient seal means of the O-ring type, an annularly split, tubular, metal ring.
- FIG. 1 is a fragmentary view in cross-section through a rotary mechanism having an inner seal assembly according to a first embodiment of the invention
- FIG. 2 is an enlarged, fragmentary view in cross-sec I tion of the inner seal assembly shown in FIG. 1;
- FIG. 3 is a fragmentary, cross-sectional view taken substantially along line 3-3 of FIG. 2, on a slightly smaller scale and with parts broken away for illustration purposes;
- FIG. 4 is a fragmentary, cross-sectional view, similar to FIG. 2, showing another embodiment of the invention.
- FIG. 5 is a view similar to FIGS. 2 and 4 showing third embodiment of this invention.
- FIG. 6 is a view similar to FIGS. 2, 4 and 5 illustrating a fourth embodiment of the present invention.
- FIG. 7 is a view in cross-section of a fifth embodiment of the invention.
- the reference number 10 generally designates an inner seal assembly according to one embodiment of this invention, which assembly is disposed in a rotary mechanism 12 of the type such as disclosed in the U.S. Pat. No. 2,988,065.
- the rotary mechanism 12 which may be an internal combustion engine, comprises a rotor 14 which is mounted on the eccentric portion 16 of a crankshaft 18 for rotation within a housing consisting of a peripheral wall 20 and two opposite end walls 22 (only one of which is shown).
- the surface 24 of peripheral wall 20 may have, in cross-section, a double epitrochoidal shape so that, with rotor 14 of three-sided configuration, a plurality of working orcombustion chambers (not shown) are formed which successively expand and contract in volumetric size as the, rotor rotates.
- apex seals 26 are carried by the rotor at the juncture of the side walls thereof to abut the peripheral wall surface 24.
- a seal means 36 is mounted on the face 32 of rotor 14 to impinge surface 34 and thereby minimize gaseous fluid leakage from the combustion chambers (not shown) in space 30.
- inner seal assembly 10 is disposed in an annular groove defined by a peripheral step 42 in a disk 44, an axially extending annular inner wall 46 in face 32 of rotor 14, and the surface 34 of end wall 22.
- the disk 44 is connected to eccentric 16 of crankshaft 18 by suitable means, such as a plurality of bolts 48 (only one, of which is shown).
- a seal-ring 50 is carried by disk 44 to prevent liquid in the area 40 from bypassing inner seal assembly 10.
- inner seal assembly 10 comprises a seal-ring 52, a support ring 54 interconnected with seal-ring 52 for conjoined rotation and limited axial movement relative to each other, and a biasing means 56, such as a wavy spring washer or the like, disposed between the support and seal-ring to urge the rings axially away from each other.
- An annular seal means 58 such as an O-ring or the like, carried by sealring 52 completes the inner seal assembly.
- the seal-ring 52 has a radially extending sealing face 60 which abuts the radially extending wall 62 of disk 44.
- the inner peripheral surface 64 of seal-ring 52 is in contact with and is supported on the axially extending surface 66 of step 42 of disk 44.
- An annular stepped portion 68 is provided in the outer peripheral surface of seal-ring 52 on which is seated an O-ring 58 and, when assembled in mechanism 12, contacts annular wall 46.
- the support ring 54 consists of a radially extending body portion 70 which-impinges the surface 34 of the adjacent end wall 22 of the housing of mechanism 12.
- the support ring 54 has a plurality of circumferentially spaced, axially extending, legs 72 each of which extend through arcuate shaped notches or cut-outs74 formed in inner peripheral surface 64 of seal-ring 52.
- Each of the legs 72 has a radially, outwardly extending, end portion 76 which is receivable in a radially extending groove 78 which communicates with each of the cutouts 74 in the seal ring.
- Each groove 78 and its associated cut-out 74 form a shoulder 80 which serves to engage and limit relative axial movement between sealring 52 and support ring 54 in a direction urging the rings to separate.
- the seal-ring 52 has an annular recess 82 formed in the surface adjacent to support ring 54, which forms a pocket for wavy washer 56 and permits opposite sides of washer 56 to simultaneously engage seal-ring 52 and support ring 54.
- support ring 54 is provided with a plurality of circumferentially spaced, radially extending fingers 84 each of which is receivable in one of a plurality of radial grooves 86 formed in rotor face 32 (see FIG. 3).
- the overall dimensions of the seal ring assembly 10 is such that it is receivable within the annular groove defined by step 42 in disk 44, annular wall 46, and end wall surface 34 so that wavy spring washer 56 is slightly compressed and, thereby, resiliently biases seal-ring 52 and support ring 54 into abutment against surfaces 62 and 34, respectively.
- end portions 76 of legs 72 are smaller in dimension in an axial direction than grooves 78.
- wavy spring washer 56 is positioned in annular recess 82 in seal-ring 52 and support ring 54 is interconnected with the seal-ring by insertion of legs 72 in cut-outs 74 of the seal-ring 52. Thereafter, the end portions 76 of legs 72 are bent to extend into the grooves 78 in seal-ring 52 so that, under the urging of wavy spring washer 56, end portions 76 abut shoulder 80.
- the O-ring 58 is then inserted in stepped portion 68 of the seal-ring to thus provide an inner seal assembly of unitary construction which can be readily and quickly inserted or removed from the annular step 42 of disk 44.
- the inner seal assembly functions to effect a fluid seal when the mechanism is in operation and when at a standstill.
- the O-ring 58 effects a seal along annular wall 46, while sealing face 60 of seal-ring 52 effects a seal by abutment against wall 62 of disk 44 under the urging of wavy spring washers 56.
- inner seal assembly 10 is keyed for conjoined rotation with rotor 14, O-ring 58 is only subject to the slight wear resulting from deformation caused by the small relative axial movement between rotor 14 and disk 44.
- the cooperative function of support ring 54, seal-ring 52 and wavy spring washer 56 in biasing sealing face 60 against surface 62 provides a fluid seal which is independent of liquid and gaseous fluid pressures and is maintained when the mechanism is operating or at rest.
- FIG. 4 is shown an inner seal assembly 10A according to another embodiment of this inventiom
- the inner seal assembly 10A differs from inner seal assembly 10 shown in FIGS. 1, 2 and 3, essentially only in that the spring biasing means for axially urging the support ring and seal-ring apart acts, through the O-ring rather than directly against the seal ring.
- the parts in inner seal assembly 10A corresponding to like parts of inner seal assembly 10, shall be designated by the same number but with the suffix A added thereto.
- seal-ring 52A does not have an annular recess for receiving wavy spring washer 56A and, instead, has a pressure ring 90 disposed adjacent O-ring 58A in stepped portion 68A of seal-ring 52A.
- the side of pressure ring 90 is provided with a concave surface 92 to receive O-ring 58A, while the opposite side is flat to receive abutment of wavy spring washer 56A.
- FIG. 5 is shown an inner seal assembly 103 according to a third embodiment of the present invention wherein parts correspondingto like parts of the embodiment shown in FIG. 1 to 3 are designated by the same reference number but with the suffix B added thereto.
- the inner seal assembly 10B essentially differs from the inner seal assemblies 10 and 10A in that O- ring 58B is positioned in a peripheral groove 94 formed in the seal-ring.
- the band 96 serves to minimize friction at O-ring 58B when axial relative movement between seal assembly 10B and rotor 14B occurs so that the consequent deformation of the O-ring which might occur through such frictional engagement is substantially minimized.
- the support ring 548 has axially extending, circumferentially spaced, tongue portions 98 engaging arcuate slots 100 in rotor 14 instead of the keying interconnection (fingers 84 and grooves 86) disclosed in inner seal assemblies 10 and 10A.
- band 96 may be employed in inner seal assemblies 10 and 10A, as well as in seal assembly 10B, without departure from the scope and spirit of this invention.
- the outer surface of O-ring 583 or inner wall 46B of rotor 148 may be provided with a coating of suitable material having a low coefficient of friction.
- FIG. 6 is illustrated an inner seal assembly 10C according to a still further embodiment of this invention wherein parts corresponding to like parts of the inner seal assembly shown in FIGS. 1 to 3 and 5 are identified by the same number but with the suffix C added thereto.
- seal assembly 10C from inner seal assemblies 10, 10A and 10B shown in FIGS. 1 to 5 is that, in place of the O-ring type annular seal means, a hollow metal ring 102 is provided. To provide ring 102 with radial resiliency, it is formed with an annular slit 104. A coating 106 of low coefficient material may be applied to the outer surface of ring 102 thereby diminishing the amount of frictional contact between the ring and inner wall 46C of rotor 14C and the surfaces of stepped portion 68C of seal-ring 52C.
- the coating 106 may be composed of polytetrafluoroethylene or other material having selflubricating characteristics.
- insert 108 may be employed in inner seal assemblies 10, 10A, and 108 without deviation from the scope and spirit of the present invention.
- support ring 54C has axially extending, circumferentially spaced, tongue portions 98C which engage arcuate slots in rotor 14C to thereby key inner seal assembly 10C to the rotor for conjoind rotation therewith.
- FIG. 7 is illustrated an inner seal assembly 10D according to a fourth embodiment of this invention, wherein parts corresponding to like parts of inner seal assembly 10 are designated by the same number but with the suffix D added thereto.
- annular membrane 109 of resilient material such as rubber or resilient plastic
- the clamping ring 1 12 may be made of material having selflubricating characteristics so as to minimize the friction between the face 115 of ring 112 and surface 62D of disk 44D.
- the outer peripheral portion 114 of membrane 109 is formed with a U-shape in cross-section so as to embrace an annular flange 116 which is attached to support ring 54D.
- the portion 114 is dimensioned so that when the axially extending flange portion 118 of inner seal assembly 10D is inserted in an annular groove 120 in rotor 14D, the portion 114 is compressed and sealingly engages the wall 122 of groove 120.
- This clamping of support ring 54D in groove 120 of rotor 14D secures support ring 54D against axial movement relative to rotor 14D.
- the axial movement of seal-ring 52D relative to disk 44D is limited in a direction away from support ring 54D by a flanged end portion 126 of an annular ring l24 which radially extends into the line of axial movement of a plurality of lugs 128 extending radially from the inner periphery of seal-ring 52D.
- the annular ring 124 may be constructed of sheetmetal and suitably fastened, as by welding or the like, to leg 72D of support ring 54D.
- the lugs 128 are located to extend into the space between three or more circumferentially spaced, axially extending ribs 130 formed on legs 72D of support ring 54D.
- the biasing means 56D comprises in this inner seal assembly a plurality of separate segments with each segment disposed in the space between the adjacent ribs 130.
- the lugs 128 and ribs 130 coact to spline connect the support ring 54D and seal-ring 52D for conjoined rotation.
- inner seal assembly 10D similar to the previously described inner seal assemblies, is a unitary assembly and is connected to rotor [40 to rotate with the latter and be rotatively carried relative to disk 44D.
- membrane 109 may be molded at its peripheral portion 114 to annular flanges 116 and 118 of support ring 54D, or, if a separate element forced into engagement with the support ring and/or bonded to the latter.
- the annular ring 124 may be secured to leg 72D, after the segmental biasing means 56D and seal-ring 52D are positioned relative to support ring 54D, to thereby lock seal-ring 52D to support ring 54D.
- the inner peripheral portion 110 of membrane 109 is inserted in groove 113 and clamped in place by securing ring 112 to seal-ring 52D.
- This completed unitary inner seal assembly is then capable of being secured in rotor 14D and in the stepped portion 62D of disk 44D.
- the present invention provides a novel inner seal assembly for a rotary mechanism which is relatively simple in construction and capable of maintaining a fluid seal when the mechanism is operating or at a standstill. It is an inner seal assembly which can be preassembled as a unitary member which is capable of insertion in and removal from the rotary mechanism quickly and easily. It is an inner seal assembly which has a relatively long operative life by minimizing frictional and distortional wear on a resilient seal means forming part of the assembly.
- said support ring and seal-ring being interconnected for conjoined rotation and limited axial movement relative to each other;
- a biasing means carried by said support ring and seal-ring to urge the said support ring and seal-ring in a direction tending to separate the rings and thereby resiliently urge said seal-ring into sealing engagement with said radially extending wall;
- a resilient seal means connected to said seal-ring to thereby effect a fluid seal adjacent said axially extending wall; and V f. said seal-ring, support ring, biasing means and resilient seal means being constructed and arranged for preassembly as a unitary structure for insertion and removal from said peripheral step as a unit.
- said support ring connecting means comprises a plurality of circumferentially spaced, projecting portions each of which is receivable in a recess in the rotor.
- said support ring includes a plurality of circumferentially spaced, axially extending legs and wherein the seal-ring includes a plurality of circumferentially spaced notches for receiving said legs to thereby interconnect the support and sealrings for rotation together.
- each of said legs have a distal end portion extending radially outwardly and said notches each have a radially extending recess portion to form a shoulder, said recess being dimensioned to receive said radially, outwardly extending leg portions whereby limited axial movement of said seal and support rings in a direction away from each other is achieved.
- said resilient seal means is an O-ring carried by the seal-ring to abut said axially extending wall.
- said resilient seal means is an annularly split, tubular ring.
- said resilient seal means is an annular ring-shaped membrane connected at one peripheral portion to the support ring and at the other peripheral portion connected to the seal-ring.
- a biasing means carried by said support ring and seal-ring to resiliently urge the support ring and seal-ring in a direction to separate the rings and thereby urge said seal-ring into sealing engagement with said radially extending wall;
- said support ring having means for connection with said rotor so that the inner seal assembly rotates with said rotor.
- support ring, biasing means and resilient sealing means are constructed and arranged for interconnection into a unitary structure capable of placement on and removal from said peripheral step.
- said resilient seal means is an O-ring carried by the peripheral portion of the seal-ring so as to sealing engage said axially e t ndin w ll.
- said means for connecting the support ring to said rotor is spline means disposed around the periphery of the support ring and engaging corresponding spline means on said rotor.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Sealing Devices (AREA)
- Mechanical Sealing (AREA)
- Pistons, Piston Rings, And Cylinders (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE2052623A DE2052623C3 (de) | 1970-10-27 | 1970-10-27 | Innendichtung für eine Kreiskolbenmaschine |
Publications (1)
Publication Number | Publication Date |
---|---|
US3706514A true US3706514A (en) | 1972-12-19 |
Family
ID=5786259
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US179059A Expired - Lifetime US3706514A (en) | 1970-10-27 | 1971-09-09 | Inner seal assembly for rotary mechanisms |
Country Status (6)
Country | Link |
---|---|
US (1) | US3706514A (fr) |
JP (1) | JPS5440685B1 (fr) |
DE (1) | DE2052623C3 (fr) |
FR (1) | FR2111545A5 (fr) |
GB (1) | GB1338269A (fr) |
IL (1) | IL37864A (fr) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4028022A (en) * | 1972-09-20 | 1977-06-07 | Nissan Motor Co., Ltd. | Oil seal assembly |
US20110033823A1 (en) * | 2008-03-18 | 2011-02-10 | Discus Dental, Llc | Rotatable ultrasonic dental tool |
US20110159454A1 (en) * | 2005-02-17 | 2011-06-30 | Discus Dental, Llc | Ultrasonic Dental Tool Having A Light Source |
US11333068B1 (en) * | 2021-03-23 | 2022-05-17 | Pratt & Whitney Canada Corp. | Side wall for rotary engine housing |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4465286A (en) * | 1983-02-22 | 1984-08-14 | The Bendix Corporation | Seal for closing a cavity |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3323712A (en) * | 1965-12-11 | 1967-06-06 | Nsu Motorenwerke Ag | Rotary internal combustion engine |
US3415444A (en) * | 1965-12-15 | 1968-12-10 | Goetzewerke | Oil seal for rotary piston internal-combustion engines |
-
1970
- 1970-10-27 DE DE2052623A patent/DE2052623C3/de not_active Expired
-
1971
- 1971-09-09 US US179059A patent/US3706514A/en not_active Expired - Lifetime
- 1971-10-06 IL IL37864A patent/IL37864A/en unknown
- 1971-10-19 FR FR7137506A patent/FR2111545A5/fr not_active Expired
- 1971-10-26 JP JP8505271A patent/JPS5440685B1/ja active Pending
- 1971-10-27 GB GB4983371A patent/GB1338269A/en not_active Expired
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3323712A (en) * | 1965-12-11 | 1967-06-06 | Nsu Motorenwerke Ag | Rotary internal combustion engine |
US3415444A (en) * | 1965-12-15 | 1968-12-10 | Goetzewerke | Oil seal for rotary piston internal-combustion engines |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4028022A (en) * | 1972-09-20 | 1977-06-07 | Nissan Motor Co., Ltd. | Oil seal assembly |
US20110159454A1 (en) * | 2005-02-17 | 2011-06-30 | Discus Dental, Llc | Ultrasonic Dental Tool Having A Light Source |
US8613617B2 (en) | 2005-02-17 | 2013-12-24 | Zila, Inc. | Ultrasonic dental tool having a light source |
US20110033823A1 (en) * | 2008-03-18 | 2011-02-10 | Discus Dental, Llc | Rotatable ultrasonic dental tool |
US8435034B2 (en) * | 2008-03-18 | 2013-05-07 | Zila, Inc. | Rotatable ultrasonic dental tool |
US11333068B1 (en) * | 2021-03-23 | 2022-05-17 | Pratt & Whitney Canada Corp. | Side wall for rotary engine housing |
Also Published As
Publication number | Publication date |
---|---|
IL37864A0 (en) | 1971-12-29 |
DE2052623C3 (de) | 1978-08-31 |
JPS5440685B1 (fr) | 1979-12-05 |
DE2052623B2 (de) | 1978-01-05 |
IL37864A (en) | 1973-10-25 |
FR2111545A5 (fr) | 1972-06-02 |
DE2052623A1 (de) | 1972-05-04 |
GB1338269A (en) | 1973-11-21 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3139233A (en) | Seal construction for rotary mechanisms | |
US3171590A (en) | Oil seal construction for rotary combustion engines | |
US3251541A (en) | Sealing construction for rotary mechanisms | |
US3134600A (en) | Seal construction for rotary mechanisms | |
US3822973A (en) | Cartridge oil seal for rotating combustion engines | |
US3706514A (en) | Inner seal assembly for rotary mechanisms | |
US3179331A (en) | Annular side seal for rotors of rotary engines | |
US3180562A (en) | Seals for rotary mechanisms | |
US4116593A (en) | Lubricant metering system for rotary piston mechanism | |
US3261542A (en) | Rotor and seal construction for rotary mechanisms | |
GB1342215A (en) | Rotary piston internal combustion engine | |
US3909015A (en) | Ring seal assembly for a rotary piston internal combustion engine | |
JPS5828403B2 (ja) | 端面密封装置 | |
GB1017568A (en) | Rotary piston machines | |
US3932075A (en) | Rotor and sealing grid for rotary engines | |
US3976406A (en) | Oil seal means of a rotary piston engine | |
US3802812A (en) | Internal seal for rotary piston combustion engine | |
US4047855A (en) | Rotary mechanism with improved cooling | |
US3545901A (en) | Rotor for rotary piston engines | |
US3868753A (en) | Method for assembly of a rotary piston internal combustion engine | |
US3540815A (en) | Sealing means for rotary internal combustion engines | |
US3127096A (en) | Froede | |
US3880555A (en) | Corner seal spring for rotary engine | |
US3781148A (en) | Apex seal assembly of a rotary piston engine | |
US3396708A (en) | Oiltight sealing device for rotary piston engines |