Buehler Turbocraft History Notes - By Royce A. Hamilton also licensed his design to Dowty Equipment of. 1959 Owner's Manual, p10 1959 Owner's. Buehler Turbocraft Manual Search? After reading the response about the Dowty Turbocraft it sounds like there is a very interesting history involving the boats.
So It begins. I have allways liked the Jet type boat, and Idealy an early version which looks 'right' I have as an ebay saved search 'dowty' and 'Jet' which comes from another intrest, this showed a Local (less than 5 miles) speed boat in need of restration, some thing I hadnt even contmpleted, I promplety went to view the boat, it was in quite a state, but did look sound and I was impressed with the quality of the Hull. So Im in at the deep end, I will have a steep learning curve ahead, as I dont know a lot about Fibre glass, Mechanicals are less of a problem. I have been considering the ooptions for chaning the engine, as it is not a MK1 Turbocraft and has a different strearing nozzle arangement, I believe that it is probbley less important that I retain the orignal 2.5 Ford cast Iron engine. I have been considering the options, such as an all alloy V8 (Lexus as I have 2 spare) and limit the revs and also the accleration rate with a ECU system, a Stright six alloy engine from a BMW or the Toyota 3L stright 6 alloy head and cast block. I would like to keep the weight low and also improve the eficancy of the system IE MPG. I have had some intresting discusions with an ECU manufacturer which I have used when tuning Cars, where we can use a pizco electronic sensor to detect cavatation and use the Traction controll channel on the ECU to retard the Ing and or rain in the engine revs to prevent the Cavation.
Any way that all a long way in the furure, I want to keep the Boat lookin 60's style and look orignal. So the Firt thing to do is to strip and make repars to the Hull and also the Pump. I have some photos at this stage one of the process. I think I might have to build a special section for Dowty as it is certainly catching on.
The quality of the build is excellent, but sadly the design does make certain problems and these are not easy to overcome. You have a great project there and in fact it is better than it looks. The engine looks like it has had a bit of abuse, but them that is not too bad to rectify if the block is not cracked. I do have a spare block, but it is cracked. I see the sacrificial anode in the jet drive has been eaten, which means the shaft will possibly need attention as there is an anode around it, but that is complete disassembly. The jet is not too bad to take apart, but the tollerances are fine when reassembling, something I am doing right now and spares unavailable, so have to be made.
Been there, done it and now wear the T shirt, so ask if you need bits made. Thanks the project will by a good one, I just about have the pump in bits, pics to follow. There are a few options so I will measure and assess the condition of the parts, I will no doubt be in touch as if you have had parts made for your machine it would be logical to use the same skilled people. I have considered some internal pump upgrades, this would keep the boat looking authentic but may improve peformance and eficiency too.
A bit like the moden E-Type Jag which you can buy. This is some thing that I wouldnt consider if it was the MK1, I could keep it orignal tho.
Hi Nigel, because your project is so important, I hope you do not mind, but I have given you a seperate board, so as to keep history going and inform others of the boats design, build and methods of repair. I look forward to your progress.
All the best. By the way, your trailer is an original trailer, I can identify it by the winch post, over engineered basically and the tie downs behind the wheels. I have built new trailers for both of my boats as I need safety on the roads and I take my boats abroad, so should you need a trailer, we have the design and could build for a lot less than most, plus galvanise and they tow like a dream. Your engine has a tap on the redundant thermo housing, when you find out what that is for, please let me know. Also your plumbing is quite different to the MK1's I have. I see another difference, your rear engine support is covered to stop fingers in the flywheel and you have a double set of engine rubber mounts, interesting. I wish I had the steering wheel centre, mine are both missing.
The internals of the jet, could be updated, but as mine is so original, I have kept it as is. The alloy sacrificial anode on the inner shaft is alloy and coated, that cost hurt me to have it made and coated as a one off. Finally, I have had made by hand the bow eye in stainless, so if you would like one as they are originally plated brass, let me know. I would need a pattern from yours as they are all hand made, but we produce them a lot less than having them re plated. I am making one right now for my second boat. Congrats on your dowty turbocraft.
Im no engineer yet a dowty enthusiast.I went through the decision of wether to change the engine or not and I plumped for keeping but tweeking the ford zephyr. I simply put on a bigger carb.with a new port plus I think the head was shaved just a little.There is a zephyr specialist near dartford who supplied all the spares advice etc.he used to race the cars! Ive got loads of guts now as it was a bit underpowerd for planing etc.I thought why get a dowty to change the engine?its like just buy a more modern boat it will be cheeper easier,maybe not as classy given? I did see a swedish boat with a merc cruiser in it.on the web.i thought wow reliability.no jet to worry about.no grit in the intakes.easy servicing.no parts problems.but.nah.I lll stick with the history and headaches! Congrats on your dowty turbocraft.
Im no engineer yet a dowty enthusiast.I went through the decision of wether to change the engine or not and I plumped for keeping but tweeking the ford zephyr. I simply put on a bigger carb.with a new port plus I think the head was shaved just a little.There is a zephyr specialist near dartford who supplied all the spares advice etc.he used to race the cars! Ive got loads of guts now as it was a bit underpowerd for planing etc.I thought why get a dowty to change the engine?its like just buy a more modern boat it will be cheeper easier,maybe not as classy given? I did see a swedish boat with a merc cruiser in it.on the web.i thought wow reliability.no jet to worry about.no grit in the intakes.easy servicing.no parts problems.but.nah.I lll stick with the history and headaches!
US3637323A - Variable-pitch bladed rotors - Google Patents US3637323A - Variable-pitch bladed rotors - Google Patents Variable-pitch bladed rotors Info Publication number US3637323A US3637323A US3637323DA US3637323A US 3637323 A US3637323 A US 3637323A US 3637323D A US3637323D A US 3637323DA US 3637323 A US3637323 A US 3637323A Authority US Grant status Grant Patent type Prior art keywords pitch blade plunger blades means Prior art date 1968-07-08 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 Inventor John Alfred Chilman Alfred Herbert Walter Loynes Peter Spence 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.) Dowty Rotol Ltd Original Assignee Dowty Rotol Ltd 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.) 1968-07-08 Filing date 1969-06-18 Publication date 1972-01-25 Grant date 1972-01-25 Links. Images.
Classifications. B— PERFORMING OPERATIONS; TRANSPORTING. B64— AIRCRAFT; AVIATION; COSMONAUTICS.
B64C— AEROPLANES; HELICOPTERS. B64C11/00— Propellers, e.g. Of ducted type; Features common to propellers and rotors for rotorcraft. B64C11/30— Blade pitch-changing mechanisms Abstract. A variable-pitch bladed rotor having a pitch-change motor which includes a casing and a diaphragm device which together define on one side of the device a closed chamber for fluid under pressure, and on the other side of the device an actuator chamber.
Means are provided for varying the pressure of fluid in the actuator chamber, and means are connected to the diaphragm device for transferring movement thereof, consequent upon such variation in pressure, to the blades to vary their pitch. United States Patent Chilman et a1. 25, 1972 VARIABLE-PITCH BLADED ROTORS Inventors: John Alfred Chilman, Painswick; Alfred Herbert Walter Loynes, Tewkesbury; Peter Spence, Cheltenham, all of England Assignee: Dowty Rotol Limited, Gloucester, England Filed: June 18, 1969 Appl.
No.: 834,297 Foreign Application Priority Data July 8, 1968 Great Britain.32,404/68 U.S.Cl.4l6/139,4l6/46,416/153, 416/157 Int. Cl.B64c 11/40 Field of Search 416/46, 48, 139, 140, 153, 416/154, 155, 157, 160, 44, 51,144, 45; 92/98 RD References Cited UNITED STATES PATENTS R 2 5,0 Biermann.4I6/I54X 2,702,023 2/1955 Seeloff.;.92/98 RD UX 2,722,985 1 1/1955 Biermann.4l6/46 3,115,9 Biermann.4l6/46 2,815,5 Fiacco 4l6/l53 X Primary Examiner-Everette A. Attorney-Young & Thompson 5 7 ABSTRACT A variable-pitch bladed rotor having a pitch-change motor which includes a casing, and a diaphragm device which together define on one side of the device a closed chamber for fluid under pressure, and on the other side of the device an actuator chamber. Means are provided for varying the pressure of fluid in the actuator chamber, and means are connected to the diaphragm device for transferring movement thereof, consequent upon such variation in pressure, to the blades to vary their pitch. 3 Claims, 5 Drawing Figures PATENIED M25197? 1637.323 ALFRED H M lay/v56 P5754 JPE/VCE iNVENTORS AT TORNEYS PATENTED JANZS I972 sum 2 0? 4 JOHN 4 CH0.
MA/V 440950 4% lay/v53 Parse J'PJNCE INV ENTORS BY W.WW ATTORNEYS PATENTEDJAN25B72 3.637.323 ' SHEET 30F 4 Jm-m/ C'H/LMAN mr/esp A4 W dam/Es a PETE/e SPAM/c INVENTORS BY M 74 4 ATTORNEYS VARIABLE-PITCH BLADED ROTORS This invention relates to variable-pitch bladed rotors. According to this invention a variable-pitch bladed rotor includes a pitch-change motor having a casing and a diaphragm device which together define, on one side of the diaphragm device, a closed chamber for containing a fluid under pressure, and on the other side of the diaphragm device, an actuator chamber, means for varying the pressure of fluid in the actuator chamber, and means connected to the diaphragm device for transferring movement thereof, consequent upon such variation in pressure, to the blades to vary their pitch. The diaphragm device may comprise two diaphragms, spaced apart the one from the other, connected at their outer edges to the casing and connected at their central portions to a rigid member. The size and nature of the two diaphragms are such that during their movement with the rigid member, each undergoes a rolling action or an unrolling action according to its direction of movement. The means for transferring movement of the diaphragm device may comprise a linkage which mechanically connects said rigid member to the blades. The linkage may comprise a rigid hollow tube extending coaxially of the rotor and carrying or having formed therewith a yoke member by which the rigid hollow tube is coupled to crankpins carried by the blades.
The rigid hollow tube may be open to the actuator chamber and fluid under pressure be conveyed to that chamber through the rigid hollow tube. The flow of fluid to the actuator chamber may be under the control of manually adjustable valve means arranged coaxially with respect to the tube, the tube in moving with the diaphragm device affording followup under the manually initiated pitch-change motor control. The rotor may be a propeller. In this case the blades thereof may be provided with flyweights which are so positioned as in operation of the propeller to afford bias of the blades in the pitch-coarsening direction, the fluid in the closed chamber preferably also urging the diaphragm device and the blades in the pitch-coarsening direction. Where the displacement of the pitch-change motor for blade pitch-change is required only to be of relatively small order, the diaphragm device may comprise a rigid member surrounded by a ring of flexible material, for example, rubber bonded thereto, and also bonded to the inner surface of the casing. At least one blade may carry a plunger at its root portion which is engageable with an indent, stop or the like, in the structure of the hub set in a position corresponding to a predetermined blade angle. Engagement of the plunger with said indent, stop or the like is intended to occur with reduction of centrifugal force thereupon when the rotor slows down below a predeten'nined rotational speed, thereby to hold the blades at said predetermined blade angle.
Preferably, the predetermined blade angle referred to above is of low (fine) order to afford low drag during starting of the engine driving the propeller. The above plunger and latch arrangements ensure that stopping of the propeller occurs with the blades in the predetermined pitch position in readiness for the next engine/propeller startup. A variable-pitch bladed rotor as claimed in claim 2, wherein said sleeve has a cap member which is readily removable therefrom for access to said plunger, said cap member retaining spring means which act upon the plunger in opposition to centrifugal force.