US3639079A - Flexible-bladed fan with improved reinforcing cap - Google Patents

Flexible-bladed fan with improved reinforcing cap Download PDF

Info

Publication number
US3639079A
US3639079A US18856A US3639079DA US3639079A US 3639079 A US3639079 A US 3639079A US 18856 A US18856 A US 18856A US 3639079D A US3639079D A US 3639079DA US 3639079 A US3639079 A US 3639079A
Authority
US
United States
Prior art keywords
cap
fan
arm
blade
blade structure
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
Application number
US18856A
Other languages
English (en)
Inventor
Shrinivas V Pratinidhi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens Bendix Automotive Electronics Ltd
Bendix Engine Components Ltd
Fram Corp
Original Assignee
Fram Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Fram Corp filed Critical Fram Corp
Application granted granted Critical
Publication of US3639079A publication Critical patent/US3639079A/en
Anticipated expiration legal-status Critical
Assigned to SIEMENS-BENDIX AUTOMOTIVE ELECTRONICS LIMITED reassignment SIEMENS-BENDIX AUTOMOTIVE ELECTRONICS LIMITED MERGER (SEE DOCUMENT FOR DETAILS). EFFECTIVE DATE: OCT. 1, 1988 Assignors: 67393 ONTARIO LIMITED, BENDIX ELECTRONICS LIMITED, SBAE CANADA HOLDINGS LIMITED
Assigned to BENDIX ENGINE COMPONENTS LIMITED reassignment BENDIX ENGINE COMPONENTS LIMITED CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). EFFECTIVE 10-01-85 Assignors: CANADIAN FRAM LIMITED
Assigned to BENDIX ELECTRONICS LIMITED reassignment BENDIX ELECTRONICS LIMITED CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). EFFECTIVE DATE: 06/02/86 Assignors: BENDIX ENGINE COMPONENTS LIMITED
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/26—Rotors specially for elastic fluids
    • F04D29/32—Rotors specially for elastic fluids for axial flow pumps
    • F04D29/38—Blades
    • F04D29/382—Flexible blades

Definitions

  • the principal object of this invention is to relieve stresses and reduce metal fatigue in high-capacity, large-bladed fans.
  • Other objects are to reinforce such fan blades without substantially altering the overall size, weight or conformation of the fan, while preventing excessive blade vibration and maintaining low-fan noise levels.
  • the invention features, in a fan having a hub, a plurality of arms extending radially outwardly of the hub, and blade structures comprising resilient trailing portions which decamber as rotational speed increases, one blade structure being secured to each arm, reinforcing caps, one said cap secured to each blade structure and the respective arm and each said cap comprising a trailing decamber-limiting portion extending partially coextensively with the trailing portion of the blade at an acute angle to the trailing portion of the blade, and two radially spaced integrally formed upstanding lips, one disposed along each opposed radially spaced side edge of said cap and of this decamber-limiting portion thereof, whereby periodic stresses induced in the cap during decambering of the trailing portion ofthe blade against the decamber-limiting portion are resisted without excessive metal fatigue in the cap.
  • the lips are each up to oneeighth inch high, and are parallel to one another; the cap is sized to be partially coextensive with the blade structure past the end of the arm; and, a plurality of fasteners (e.g., rivets) extend through cap, blade structure, and arm, and at least one fastener extends through the cap and blade only.
  • a plurality of fasteners e.g., rivets
  • FIG. 1 is a plan view of the upstream side of an engine cooling fan embodying the present invention
  • FIG. 2 is a side elevational view ofthe fan of FIG. 1;
  • FIG. 3 is an enlarged sectional view of an arm and blade structure of the fan taken along the line 33 of FIG. 2;
  • FIG. 4 is a sectional view of an arm and blade structure of the fan taken along the line 4-4 of FIG. 3;
  • FIG. 5 is an end view of a reinforcing cap taken along the line 55 ofFIG. 3.
  • FIGS. 1 and 2 there is shown in FIGS. 1 and 2 generally at 11 an engine cooling fan adapted for use on a motor vehicle.
  • the fan has a central planar hub 12, with asymmetrically disposed arms 13 extending therefrom.
  • each arm has a twisted section 14 joining it to the hub so that the plane of each arm is at an angle to the plane of the hub.
  • a blade structure 15 is secured to the upstream side of each arm 13, and includes a leading blade member 16 formed of a relatively rigid steel (SAE 950, prepainted, 0.024 inch thick) and defining a leading edge at 17, and a trailing blade portion defined by member 18, formed of a resilient steel (AISI 301 stainless steel, 0,018 inch thick), and defining a trailing edge at 19, which is substantially parallel to leading edge 17.
  • SAE 950 relatively rigid steel
  • member 18 formed of a resilient steel (AISI 301 stainless steel, 0,018 inch thick), and defining a trailing edge at 19, which is substantially parallel to leading edge 17.
  • each blade member 18 Provided at the trailing edge of each blade member 18 is a weight 20.
  • the weight 20 is an integral portion of blade member 18 folded upon itself at the trailing edge so as to engage the convex side of the blade member, and has a mass of about 15 percent of the total mass of the blade member 18, Such weights are fully described in my copending US. Pat. application Ser. No. 857,849, filed Sept. 15, 1969, now US. Pat. No. 3,594,098 entitled Fan with Weighted Flexible Blades.”
  • each blade member 16, 18 overlies the arm 13 to which it is mounted on the upstream side of the arm, and is secured to the arm by a reinforcing cap 24 and rivets 25.
  • leading member 16 and flat portion 28 of trailing member 18 are secured between reinforcing cap 24 and the upstream side of arm 13 by the rivets therethrough, and additionally to the cap 24 and to one another by the rivet 29.
  • the trailing portion of trailing member 18 is curved through the plane of arm 13 toward the downstream end of the fan, convexly as viewed in FIG. 1, away from the plane of hub 12, whereas the leading portion ofleading member 16 is bent toward the plane of hub 12.
  • the angle a of the chord plane c between the leading edge 17 and the trailing edge 19 with the plane of hub 12 is about 32. To provide this chord angle, leading member 16 as illustrated is bent at an angle of about l5 relative to the plane of arm 13.
  • the reinforcing cap 24 (0.048 inch-thick prepainted SAE 950A steel is of convex shape on its upstream side to provide a decamber-limiting trailing portion 24a disposed at an acute angle to the adjacent trailing blade member 18.
  • Cap 24 has along its convex upstream side a first integrally formed lip 30 extending along its one side edge and a second integrally formed lip 32, parallel to lip 30, extending along its opposite side edge radially spaced from said one side edge, as shown in FIG. 4, the lips also extending along the portion of said edges defined by the decamber-limiting portion of the cap.
  • Cap 24 is sized to be partially coextensive with blade members 16 and 18 past the outer end of arm 13 to receive rivet 29, thereby to reduce vibrations of the blade members l6, l8 and also fan noise,
  • the lips 30, 32 are integrally formed by turning up the edges of cap 24 toward the concave side of the cap. The amount of turnup depends on the strength required for adequately supporting a decambered blade, but is preferably not greater than about one-eighth inch.
  • the arms 13 are arranged for balance of the fan, and the arcuate distances between the reference lines 40, 41, 42, 43, 44 (drawn radially of hub 12 and parallel to the edges 17, 19) are as follows:
  • a fan having a hub, a plurality of'arms extending radially outwardly of said hub, and blade structures comprising resilient trailing portions which decamber as rotational speed increases, one blade structure being secured to each said arm,
  • each said cap secured to each blade structure and the respective said arm, and each said cap comprising (a) a trailing decamber-limiting portion extending partially coextensively with the trailing portion of said blade structure at an acute angle to said trailing portion of said blade structure, and (b) two radially spaced integrally formed upstanding lips, one disposed along each opposed radially spaced side edge of said cap and of said decamber-limiting portion thereof, whereby periodic stresses induced in said cap during decambering of said trailing portion of said blade structure against said cap are resisted without excessive metal fatigue in said cap.
  • each said lip extends no more than one-eighth inch above the remaining surface ofsaid cap.
  • the fan of claim 3 including a plurality of fasteners extending through said cap, said blade structure, and said arm and at least one fastener extending only through said cap and said blade structure.
  • each said lip extends no more 5 than about one-eighth inch above the surface of said cap.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
US18856A 1970-03-12 1970-03-12 Flexible-bladed fan with improved reinforcing cap Expired - Lifetime US3639079A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US1885670A 1970-03-12 1970-03-12

Publications (1)

Publication Number Publication Date
US3639079A true US3639079A (en) 1972-02-01

Family

ID=21790101

Family Applications (1)

Application Number Title Priority Date Filing Date
US18856A Expired - Lifetime US3639079A (en) 1970-03-12 1970-03-12 Flexible-bladed fan with improved reinforcing cap

Country Status (6)

Country Link
US (1) US3639079A (enExample)
JP (1) JPS5341362B1 (enExample)
CA (1) CA922288A (enExample)
DE (1) DE2111263C3 (enExample)
FR (1) FR2084508A5 (enExample)
GB (1) GB1342608A (enExample)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3728043A (en) * 1972-01-12 1973-04-17 Fram Corp Flexible blade fan with ribbed blades
US3860362A (en) * 1973-12-14 1975-01-14 Ford Motor Co Flexible bladed fan

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1799745A (en) * 1928-12-01 1931-04-07 Aircraft Specialties Company Airplane propeller blade
US3044557A (en) * 1959-01-08 1962-07-17 American Metal Prod Variable pitch fan blade
US3289924A (en) * 1965-05-10 1966-12-06 William Wallace Corp Flexible blade fan
US3356154A (en) * 1966-11-16 1967-12-05 Ford Motor Co Flexible blade engine cooling fan
US3406760A (en) * 1967-09-18 1968-10-22 Wallace Murray Corp Flexible blade fan
US3490686A (en) * 1968-03-14 1970-01-20 Wallace Murray Corp Fan drive

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1799745A (en) * 1928-12-01 1931-04-07 Aircraft Specialties Company Airplane propeller blade
US3044557A (en) * 1959-01-08 1962-07-17 American Metal Prod Variable pitch fan blade
US3289924A (en) * 1965-05-10 1966-12-06 William Wallace Corp Flexible blade fan
US3356154A (en) * 1966-11-16 1967-12-05 Ford Motor Co Flexible blade engine cooling fan
US3406760A (en) * 1967-09-18 1968-10-22 Wallace Murray Corp Flexible blade fan
US3490686A (en) * 1968-03-14 1970-01-20 Wallace Murray Corp Fan drive

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3728043A (en) * 1972-01-12 1973-04-17 Fram Corp Flexible blade fan with ribbed blades
US3860362A (en) * 1973-12-14 1975-01-14 Ford Motor Co Flexible bladed fan

Also Published As

Publication number Publication date
DE2111263C3 (de) 1979-04-26
CA922288A (en) 1973-03-06
GB1342608A (en) 1974-01-03
DE2111263A1 (de) 1971-09-23
FR2084508A5 (enExample) 1971-12-17
JPS5341362B1 (enExample) 1978-11-02
DE2111263B2 (de) 1978-09-07

Similar Documents

Publication Publication Date Title
US3406760A (en) Flexible blade fan
US3751181A (en) Fan for cooling automotive vehicle engine
US4893990A (en) Mixed flow impeller
US3044557A (en) Variable pitch fan blade
US4046488A (en) Radiator cooling fan
US4746271A (en) Synthetic fan blade
US3594098A (en) Fan with weighted flexible blades
US3289924A (en) Flexible blade fan
US3711219A (en) Fan connecting reinforcing cap to hub
CA1101812A (en) Flexible fan
US3679321A (en) Prestressed flexible bladed fan
US4251189A (en) Fan
US3639079A (en) Flexible-bladed fan with improved reinforcing cap
US4025231A (en) Propeller fan construction
US4037987A (en) Flexible bladed fan with increased natural frequency
US3356154A (en) Flexible blade engine cooling fan
US4334824A (en) Flexible fan device
US4105366A (en) Twisted flex fan
KR930004200B1 (ko) 송풍기 날개
US2317502A (en) Propeller type ventilator fan
US3914069A (en) Axial flow fan having fully streamlining flexible blades
US3639078A (en) Flexible-bladed fan with extended blade structure
US3910718A (en) Limited deflection flexible bladed fan for use with viscous shear clutch
US3728043A (en) Flexible blade fan with ribbed blades
US4050847A (en) Lightweight fan

Legal Events

Date Code Title Description
AS Assignment

Owner name: BENDIX ENGINE COMPONENTS LIMITED

Free format text: CHANGE OF NAME;ASSIGNOR:CANADIAN FRAM LIMITED;REEL/FRAME:005224/0475

Effective date: 19880911

Owner name: BENDIX ELECTRONICS LIMITED

Free format text: CHANGE OF NAME;ASSIGNOR:BENDIX ENGINE COMPONENTS LIMITED;REEL/FRAME:005271/0503

Effective date: 19860105

Owner name: SIEMENS-BENDIX AUTOMOTIVE ELECTRONICS LIMITED

Free format text: MERGER;ASSIGNORS:SBAE CANADA HOLDINGS LIMITED;67393 ONTARIO LIMITED;BENDIX ELECTRONICS LIMITED;REEL/FRAME:005271/0515

Effective date: 19881001