US3867871A - Piston-to-rod detachable connection - Google Patents
Piston-to-rod detachable connection Download PDFInfo
- Publication number
- US3867871A US3867871A US354724A US35472473A US3867871A US 3867871 A US3867871 A US 3867871A US 354724 A US354724 A US 354724A US 35472473 A US35472473 A US 35472473A US 3867871 A US3867871 A US 3867871A
- Authority
- US
- United States
- Prior art keywords
- piston
- shoulder
- ring
- hold
- rod
- 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
- 230000000295 complement effect Effects 0.000 claims description 8
- 230000013011 mating Effects 0.000 claims description 8
- 230000006835 compression Effects 0.000 claims description 3
- 238000007906 compression Methods 0.000 claims description 3
- 238000010276 construction Methods 0.000 description 3
- 241000237519 Bivalvia Species 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 235000020639 clam Nutrition 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
Images
Classifications
-
- 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
- F16J1/00—Pistons; Trunk pistons; Plungers
- F16J1/10—Connection to driving members
- F16J1/12—Connection to driving members with piston-rods, e.g. rigid connections
-
- 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
- F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
- F16B3/00—Key-type connections; Keys
-
- 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
- F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
- F16B2200/00—Constructional details of connections not covered for in other groups of this subclass
- F16B2200/40—Clamping arrangements where clamping parts are received in recesses of elements to be connected
- F16B2200/406—Clamping parts being collars, bushings or wedges
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T74/00—Machine element or mechanism
- Y10T74/21—Elements
- Y10T74/2142—Pitmans and connecting rods
Definitions
- ABSTRACT [52] US. Cl 92/258, 92/257, 403/261 Detachable Connection of a piston Onto a reduced i [5 6 ameter ection of a rod at a location thereQn between [58] Field of Search 92/257, 258, 255, 251; Spaced apart Shoulders provided by the reduced i 403/261 eter section.
- the piston is wedged into final tightness by clamped double angle wedging segments, the [56] References C'ted clamping being accomplished by a plurality of diamet- UNITED STATES PATENTS ric pairs of threaded, piston hold-down devices.
- This application relates to a detachable connection of a piston onto a reduced diameter section of a. rod, at a location thereon between spaced apart shoulders provided by the reduced diameter section.
- the piston and rod assembly reciprocate under power in a work performing device, including but not. limited to hydraulic power cylinders, for example.
- My invention has the objects of the drop hammer cylinder US. Pat. No. 2,211,717 and the Pat. No. 3,1 15,071 for hydraulic cylinders for large earth moving machines, the disclosures of which patents are incorporated in entirety herein by reference.
- One of several such objectives is to avoid certain limitations encountered with threaded connections, involving the necessary cutting of threads at one or more points on the rod end. It is well known to have a piston retainer internally threaded, or the piston internally threaded, or both, for securement onto companion threads of the rod.
- My invention has the additional objective of avoiding certain things encountered in the patented structures, namely, the limitations encountered from taking resort to a split piston construction, a split retainer construction, and a split clamp, if any, as disclosed in the patents. That is to say, the patented structures while entirely feasible and doubtless commercially attractive, employ several pairs of complementary halves or parts which collectively contribute to a multiplicity of separate parts in the assembly and which in the patented designs produce manifestly limited final tightness and solidarity available in the connection.
- FIG. 1 is a longitudinal view of a hydraulic power cylinder embodying the present invention
- FIG. 2 is a cross sectional longitudinal view of the connection between piston and rod within the cylinder of FIG. 1;
- FIG. 3 is a top plan view of a ring formed of plural pairs of wedging segments in the connection of FIG. 2;
- FIGS. 4, 5, and 6 show individual details respectively isometrically, in top plan, and longitudinally.
- a double acting hydraulic cylinder assembly 10 comprises a cylinder 12 having a relatively smooth bore.
- the head end of the cylinder 12 carries an end closure member 13 provided with a hole therethrough, and a bushing 14 within the hole for pivotally connecting the head end of the cylinder assembly in a tool working arrangement.
- the rod 21 at its internal end carries a piston head generally indicated at 25 and the rod carries at its external end an eye 26 with a bushing 27 therein for pivotally connecting the cylinder assembly in a tool working arrangement. Sealing between the mutually confronting piston girth and smooth cylinder bore is provided by the usual piston rings or piston packing, not shown.
- a piston 28 in the schematic shape of an endless collar in the head 25 slides over a reduced end portion 30 of the rod 21 for purposes of assembly, and rests against a piston shoulder 32 provided by the reduced section of the rod.
- a wide radial groove 34 penetrating into the reduced section of the rod overlaps axially slightly with the upper end of the piston 28 as viewed in FIG. 2.
- the piston 28 carries adjustable piston hold-down means 36 comprising an endless clamping ring 38 and piston threaded-hold-down devices 40 interconnecting the piston and clamping ring.
- An interposed split locking ring generally indicated at 42 has a double slope angle at the top formed by a first, or inner, wedging surface 44 complementary to an outwardly inclining mating shoulder 46 on the upper end of the groove 34.
- a second, or outer, wedging surface 48 on the ring 42 is complementary to an out wardly sloped mating surface 50 on the bottom of the endless clamping ring 38.
- the ring 42 projects radially inwardly into the groove 34 and has a bottom wedging surface 52 undercut at its inner end by the groove 34 and complementary to the normal upper end surface 54 of the piston 28.
- the frictional interface between the piston and ring 42 has minimal area.
- Each threaded device 40 passes noninterferingly through a radial slot 56 in tlhe ring 42 and a registering fastener opening 58 in the endless clamping ring 38.
- the reduced end portion 30 of the rod 11 is of uniform diameter except for the portion carrying the depth of the groove 34, and so the cylindrical interface of contact between the piston .28 and the rod 21 is shown with a larger diameter than the bottom of the groove 34.
- the pressure of the piston hold-down means causes endwise movement of the ring 38 toward the piston 28.
- the piston 28, clamping ring 38, and near shoulder 46 on the rod each in active response to pressure of adjustment of the hold-down means 36, and each in active engagement with a respective wedging surface 52, 48, and 44 of the ring 42 common thereto, cooperate to wedge the ring between the piston and near shoulder 46 to a radially inward locking position locking the piston in compression on the piston shoulder 32.
- the split locking ring 42 is composed preferably of at least 3 or 4 segments as generally indicated at 60. Desirably, a plurality of pairs of the segments is employed so as to act diametrically, as in the case of those segments specifically designated 60a and 60b. The reason is that only the central portion of each segment. represented by an arrow in FIG. 3, acts directly toward the center of the rod 21 and so there is no wasted component of motion. Yet although each end portion of each segment moves in a parallel path, such path is off center and thus wastes motion laterally as it approaches the center. In theory, such path would never, in fact, reach center, but would simply slide past center by the distance of its lateral offset therefrom.
- the large plurality of pairs of segments is no drawback in my invention because, despite the number, the endless clamping ring 38 thereupon precisely coordinates their radially inward movement as it commonly cams or wedges them in unison inwardly.
- a large plurality of the pairs as compared for instance to a single pair of segments each being a semicircle, increases the mechanical advantage because it raises the number of central portions of segments and proportionally reduces the wasted motion attendant with segment end portions.
- a large power wrench might be required for tightening down a comparatively enormous piston on rod threads or a comparatively enormous piston retainer nut on rod threads, whereas the connection tightened according to my invention can be taken down in stages with a simple hand wrench.
- the piston hold-down devices used can be hold-down stud and nut devices for locking the wedging, split locking ring radially in place.
- the studs of the devices would be threaded into the upper end of the piston 28, as viewed in FIG. 2.
- the devices are shown to be hold-down bolts 40 for locking the piston with the wedges.
- the bolts are threaded into tapped openings which are longitudinally disposed in the upper end of the piston 28 and, at the head end, each bolt head engages the top of the endless clamping ring 38 as viewed in FIG. 2.
- FIGS. 4, 5, and 6 By way of details, a segment 60 of the split locking ring 42, the endless clamping ring 38, with the bolt heads omitted, and the rod 11 with the piston and connection omitted are shown in respective FIGS. 4, 5, and 6.
- Applying the piston head 25 is done in a reverse sequence to the steps of detachment.
- the detachment sequence is to remove the fasteners 40, then the clamping ring 38, next the segments of the split locking ring 42, and finally the piston 28 from the rod.
- Two or more fasteners 40 are needed and two or more segments are needed in the split ring 42, and the number of each of the plural fasteners and plural segments can equal or exceed the number of the other.
- one embodiment of the invention contemplated has eight of the bolt fasteners 40 and four of the split ring segments 60.
- Detachably connected assembly comprising:
- a piston rod provided with a piston shoulder, and a shoulder confronting the piston shoulder with a space therebetween, and so spaced apart therefrom as to be in a position more near to the rod end;
- said piston, clamping ring, and near shoulder having interposed split locking ring means, said means presenting at least first and second wedging surfaces wedged against the clamping ring and against the near shoulder on respective mating surfaces of the latter so that the active engagement, in response to pressure of adjustment of the hold-down means, wedges said interposed split ring means between the piston and near shoulder to a radially inward locking position locking the piston in compression on the piston shoulder.
- the endless clamping ring as viewed in cross section with the rod end extending in one vertical direction, presenting a downwardly and outwardly sloped surface forming one of said mating surfaces and actively engaging the first wedging surface in the described way, said first wedging surface being complementary to said sloped surface.
- the near shoulder on the piston rod when the latter is viewed with the rod end extending in one vertical direction, presenting an upwardly and outwardly inclined surface forming another of said mating surfaces and actively engaging the second wedging surface in the described way, said second wedging surface being complementary to said inclined sur face.
- split locking ring means is composed of segments exceeding a pair in number.
- the hold-down means characterized by threaded hold-down devices between the endless ring and the piston to clamp down on the interposed split locking ring means, the devices exceeding a pair in number.
- the invention of claim 1 characterized by the hold-down means comprising individual threaded devices and the split locking ring means comprising individual ring segments, there being at least two pairs of threaded devices and two pairs of segments.
- the adjustable hold-down means characterized by threaded fastener means in the carrying means on the piston and received noninterferingly in radial slots in said split locking ring means.
- the split locking ring means being relieved along the radially outer portion of its interface of engagement with the piston whereby the piston and each segment at said radially outer portion of the interface of engagement have predetermined clearance preventing contact.
- the near shoulder characterized by a rod groove defining the near shoulder and undercutting said interface of engagement, whereby a radially inner portion of said interface of engagement of each segment overhangs the piston by a clearance gap preventing contact.
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Pistons, Piston Rings, And Cylinders (AREA)
Abstract
Description
Claims (10)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US354724A US3867871A (en) | 1973-04-26 | 1973-04-26 | Piston-to-rod detachable connection |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US354724A US3867871A (en) | 1973-04-26 | 1973-04-26 | Piston-to-rod detachable connection |
Publications (1)
Publication Number | Publication Date |
---|---|
US3867871A true US3867871A (en) | 1975-02-25 |
Family
ID=23394655
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US354724A Expired - Lifetime US3867871A (en) | 1973-04-26 | 1973-04-26 | Piston-to-rod detachable connection |
Country Status (1)
Country | Link |
---|---|
US (1) | US3867871A (en) |
Cited By (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4012154A (en) * | 1973-09-28 | 1977-03-15 | United Technologies Corporation | Threadless locking device |
US4019824A (en) * | 1976-02-03 | 1977-04-26 | Percy Vernon L | Positive ring retaining system |
US4647242A (en) * | 1985-02-05 | 1987-03-03 | Chang Mine K | Joint apparatus of speedometer shaft |
US4668115A (en) * | 1986-04-30 | 1987-05-26 | United Technologies Corporation | Helicopter rotor spindle retention assembly |
US4872370A (en) * | 1987-04-06 | 1989-10-10 | Pneumo Abex Corporation | Piston rod assembly including preloaded piston head and composite rod |
US4887928A (en) * | 1987-09-04 | 1989-12-19 | Wichard | Device for a screw connection between two pieces |
US4934491A (en) * | 1987-12-14 | 1990-06-19 | Atsugi Motor Parts Company, Limited | Shock absorber with improved structure of thrusting piston assembly |
US5778734A (en) * | 1995-04-12 | 1998-07-14 | Toyota Jidosha Kabushiki Kaisha | Fastening structure |
US5941162A (en) * | 1997-12-23 | 1999-08-24 | Caterpillar Inc. | Piston |
US6305870B1 (en) * | 1997-03-21 | 2001-10-23 | Piolax Inc. | Metal clip and, fixing structure for fixing shaftlike member to mount member having through hole, with the metal clip |
US20040086354A1 (en) * | 2001-08-20 | 2004-05-06 | Harris David A. | Locking fastener assembly |
US20060051182A1 (en) * | 2001-08-20 | 2006-03-09 | Gerard Jakuszeski | Fastener assembly |
US20060110232A1 (en) * | 2001-09-06 | 2006-05-25 | Maclean-Fogg Company | Threaded fastener assembly |
US20060216130A1 (en) * | 2001-08-20 | 2006-09-28 | Maclean-Fogg Company | Fastener assembly |
US20070059093A1 (en) * | 2005-09-09 | 2007-03-15 | Chun Victor L | Flanged demountable pins and bushings and method of manufacture |
US20080292395A1 (en) * | 2005-09-09 | 2008-11-27 | Chun Victor L | Guide pin with flange assembled from annular pieces and outer ring |
US20090035057A1 (en) * | 2007-07-12 | 2009-02-05 | Chun Victor L | Flangeless demountable pin system |
US20190242377A1 (en) * | 2018-02-06 | 2019-08-08 | Federal Signal Corporation | Piston head retaining system |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US936717A (en) * | 1909-10-12 | John J Hampson | Packing for pistons. | |
US1294792A (en) * | 1915-02-25 | 1919-02-18 | Hess Bright Mfg Co | Device for securing parts to their supports. |
US2211717A (en) * | 1937-07-08 | 1940-08-13 | Pneumatic Drop Hammer Co | Piston rod assembly |
US2979903A (en) * | 1957-06-21 | 1961-04-18 | Studebaker Hydraulic Products | Air-hydraulic apparatus |
US3397893A (en) * | 1966-08-03 | 1968-08-20 | Int Harvester Co | Cylinder construction |
US3426656A (en) * | 1967-06-14 | 1969-02-11 | Charles W Bimba | Air cylinder with a removably locked piston rod connection |
-
1973
- 1973-04-26 US US354724A patent/US3867871A/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US936717A (en) * | 1909-10-12 | John J Hampson | Packing for pistons. | |
US1294792A (en) * | 1915-02-25 | 1919-02-18 | Hess Bright Mfg Co | Device for securing parts to their supports. |
US2211717A (en) * | 1937-07-08 | 1940-08-13 | Pneumatic Drop Hammer Co | Piston rod assembly |
US2979903A (en) * | 1957-06-21 | 1961-04-18 | Studebaker Hydraulic Products | Air-hydraulic apparatus |
US3397893A (en) * | 1966-08-03 | 1968-08-20 | Int Harvester Co | Cylinder construction |
US3426656A (en) * | 1967-06-14 | 1969-02-11 | Charles W Bimba | Air cylinder with a removably locked piston rod connection |
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4012154A (en) * | 1973-09-28 | 1977-03-15 | United Technologies Corporation | Threadless locking device |
US4019824A (en) * | 1976-02-03 | 1977-04-26 | Percy Vernon L | Positive ring retaining system |
US4647242A (en) * | 1985-02-05 | 1987-03-03 | Chang Mine K | Joint apparatus of speedometer shaft |
US4668115A (en) * | 1986-04-30 | 1987-05-26 | United Technologies Corporation | Helicopter rotor spindle retention assembly |
US4872370A (en) * | 1987-04-06 | 1989-10-10 | Pneumo Abex Corporation | Piston rod assembly including preloaded piston head and composite rod |
US4887928A (en) * | 1987-09-04 | 1989-12-19 | Wichard | Device for a screw connection between two pieces |
US4934491A (en) * | 1987-12-14 | 1990-06-19 | Atsugi Motor Parts Company, Limited | Shock absorber with improved structure of thrusting piston assembly |
US5778734A (en) * | 1995-04-12 | 1998-07-14 | Toyota Jidosha Kabushiki Kaisha | Fastening structure |
US6305870B1 (en) * | 1997-03-21 | 2001-10-23 | Piolax Inc. | Metal clip and, fixing structure for fixing shaftlike member to mount member having through hole, with the metal clip |
US5941162A (en) * | 1997-12-23 | 1999-08-24 | Caterpillar Inc. | Piston |
US20040086354A1 (en) * | 2001-08-20 | 2004-05-06 | Harris David A. | Locking fastener assembly |
US20060051182A1 (en) * | 2001-08-20 | 2006-03-09 | Gerard Jakuszeski | Fastener assembly |
US20060216130A1 (en) * | 2001-08-20 | 2006-09-28 | Maclean-Fogg Company | Fastener assembly |
US8011866B2 (en) | 2001-08-20 | 2011-09-06 | Maclean-Fogg Company | Locking fastener assembly |
US20060110232A1 (en) * | 2001-09-06 | 2006-05-25 | Maclean-Fogg Company | Threaded fastener assembly |
US20070059093A1 (en) * | 2005-09-09 | 2007-03-15 | Chun Victor L | Flanged demountable pins and bushings and method of manufacture |
US20080292395A1 (en) * | 2005-09-09 | 2008-11-27 | Chun Victor L | Guide pin with flange assembled from annular pieces and outer ring |
US20090035057A1 (en) * | 2007-07-12 | 2009-02-05 | Chun Victor L | Flangeless demountable pin system |
US20190242377A1 (en) * | 2018-02-06 | 2019-08-08 | Federal Signal Corporation | Piston head retaining system |
US10584699B2 (en) * | 2018-02-06 | 2020-03-10 | Federal Signal Corporation | Piston head retaining system |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3867871A (en) | Piston-to-rod detachable connection | |
US4815360A (en) | Rod-piston connection | |
NZ202076A (en) | Retention of first member in bore of second member using grooves and retaining rings | |
GB1431860A (en) | Fasteners | |
US3910154A (en) | Separation nut | |
EP0397653A1 (en) | Force applicators. | |
US3807285A (en) | Connection between rod and piston of fluid power cylinder | |
US4766956A (en) | Wellhead annular seal | |
US4443016A (en) | Clamp ring device for the securing and removal of a cover over a pressure vessel | |
US4562798A (en) | Cylinder head locking construction | |
US5110244A (en) | Fastener assembly | |
GB1316841A (en) | Piston seal assembly | |
US4385514A (en) | Pipe assembly tool | |
US2970871A (en) | Piston assembly | |
US2411364A (en) | Fastening device | |
US2274927A (en) | Sleeve type piston rod | |
US2487390A (en) | Pump piston | |
US1560818A (en) | Piston packing | |
US4072434A (en) | Hydraulic cylinder with concentrically maintained piston and rod | |
US2244400A (en) | Lock-nut construction | |
US3693399A (en) | Fastener installation and crimping tool | |
US1735596A (en) | Piston packing | |
US4187767A (en) | Diesel cylinder head and liner | |
US3202059A (en) | Piston assembly | |
US2809079A (en) | Piston head structure |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: DRESSER INDUSTRIES, INC., A CORP. OF DEL. Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:INTERNATIONAL HARVESTER COMPANY;REEL/FRAME:004130/0646 Effective date: 19821101 Owner name: DRESSER INDUSTRIES, INC., A CORP. OF DEL., STATELE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:INTERNATIONAL HARVESTER COMPANY;REEL/FRAME:004130/0646 Effective date: 19821101 |
|
AS | Assignment |
Owner name: DRESSER FINANCE CORPORATION, DALLAS, TX., A DE COR Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:DRESSER INDUSTRIES, INC.;REEL/FRAME:004994/0061 Effective date: 19880831 Owner name: KOMATSU DRESSER COMPANY, E. SUNNYSIDE 7TH ST., LIB Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:DRESSER FINANCE CORPORATION, A CORP. OF DE.;REEL/FRAME:004994/0077 Effective date: 19880901 |