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Linear alternator module open frame, 2 in: frame base, leaf seats, clamp rings, stator sleeve and top plate

What frame carries the leaves and stator of the open-frame linear alternator module? · Hardware · basis: Design values, my geometry (tools/gen_la_module.py); the frame base's clamp face is the 2 in ISO 2852 end-cap profile drawn in tools/gen_hardware.py

Long Earth Society build part. The open frame of my clamp-in linear alternator module. The engines

Exact dimensions. Every file is drawn at true size with no printing tolerance. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your printer's or process's clearance before making the part. Mating features

sizes
6 in table

Notes

  • Six parts that make the open frame of my linear alternator module. The frame base clamps on the 42 mm bored spool's second ferrule with a Type B gasket and a standard 2 in clamp, exactly as an end cap; everything else stacks on it with M3 screws, nothing around the sides: leaf 1 · lower clamp ring and its three posts · stator sleeve with the stator · top plate and its three posts · leaf-2 seat ring · leaf 2 · upper clamp ring.
  • Each leaf's Ø64 rim sits in a Ø64 × 0.8 seat (the 0.8 leaf's thickness) and a flat Ø80 clamp ring presses it down, screws on r 36 outside the leaf, so no hole goes through a leaf. The rim is clamped inside r 23.75 = 47.5 / 2 exactly as in a spool joint, so the leaves' free span, stiffness and stress are the same as in the closed module. A 0.5 soft leaf sits on a 0.3 rim shim (tuning page).
  • The stator sleeve keeps the alternator's magnetic gap: its Ø50.8 outside is where the stator teeth sit (as on the bored spool) and its Ø48.00 bore leaves the same 0.5 radial gap to the Ø47 magnet carrier, so the force constant, coil and side pull are the closed module's. The bobbin goes on over the Ø64 top flange before the packs; the lower Ø80 flange carries the sleeve on the lower posts.
  • Screws: 3 × M3 × 25 down through the sleeve's lower flange, the 10 mm posts and the lower clamp ring into the frame base (7 engaged in its 7.5 mm tapped holes); 3 × M3 × 12 through the top plate into the sleeve's top flange; 3 × M3 × 16 through the upper clamp ring and the seat ring into the top plate's posts. Every tapped hole is drawn at the Ø2.5 M3 tap drill.
  • The back of the piston is at the room's pressure: it breathes through the frame base's Ø47.5 bore, past leaf 1 and out of the 10 mm side opening between the lower clamp ring and the sleeve (1492 mm² at the bore circle against the piston's 1810 mm²).
  • Every frame part is a flat ring or a round body with flat faces at both ends and no undercut; the slopes behind the base's neck and under the sleeve's top flange are 45°. Fits are in the table; everything else is drawn at size.

Sizes

partwhat it issize_mmfitsqty
la-frame-base-2in-ferruleframe base (ferrule face, leaf-1 seat)Ø80 × 28ISO 2852 face: clamp; seat Ø64 × 0.8: clamp (leaf rim); bore Ø47.5: designed1
la-frame-leaf-clamp-ring-80-posts10lower leaf clamp ring with postsØ80 × 13face on the leaf rim: clamp1
la-frame-stator-sleeve-48x66stator sleeveØ80 × 66, bore Ø48.00OD Ø50.8: clamp (stator teeth); bore Ø48.00: designed (0.5 radial gap to the Ø47 carrier)1
la-frame-stator-top-plate-80-posts5stator top plate with postsØ80 × 10faces: flat bolted joints1
la-frame-leaf-seat-ring-80leaf-2 seat ringØ80 × 4seat Ø64 × 0.8: clamp (leaf rim)1
la-frame-leaf-clamp-ring-80upper leaf clamp ringØ80 × 3face on the leaf rim: clamp1

Mating features

Drawn at the exact size. Open press, slide, run and socket features by your process's clearance; leave designed gaps and clamp fits as drawn.

featureexactmates withfitfiles
faceISO 2852 2 in end-cap face (recess Ø56.5 × 1.6, 20° back cone)Type B gasket + standard 2 in clamp on the 42 mm bored spool's second ferruleclampla-frame-base*
neckØ50.8 to 9.5 from the faceclamp groove room (no contact)designedla-frame-base*
leaf seatannulus Ø47.5–Ø64 × 0.8leaf 1's Ø64 rim (0.8 leaf, or 0.5 leaf on a 0.3 shim), clamped by the lower clamp ringclampla-frame-base*
boreØ47.5 throughcollar Ø28 and tube rod pass (no contact); the piston back breathes through itdesignedla-frame-base*
tapped holes3 × Ø2.5 × 7.5 on r 36M3 × 25 frame screws (M3 tap drill)designedla-frame-base*
clamp faceØ47.5–Ø80 flatleaf rim (inside Ø64) and the seat's top faceclampla-frame-leaf-clamp-ring*
holes3 × Ø3.4 on r 36 (through the posts)M3 clearance (ISO 273 medium)designedla-frame-leaf-clamp-ring*
post ends3 × Ø8 × 10 on r 36stator sleeve's lower flangeclampla-frame-leaf-clamp-ring-80-posts*
ODØ50.8 from s −28 to s 20stator pack teeth (r 25.4) and the housing halvesclampla-frame-stator-sleeve*
boreØ48.00 × 66magnet carrier Ø47 (0.5 radial gap, no contact)designedla-frame-stator-sleeve*
top flangeØ64bobbin bore Ø65 passes over (no contact)designedla-frame-stator-sleeve*
lower flangeØ80 × 5, 3 × Ø3.4 on r 36lower posts; M3 × 25clampla-frame-stator-sleeve*
tapped holes3 × Ø2.5 × 8 on r 28.5M3 × 12 from the top plate (M3 tap drill)designedla-frame-stator-sleeve*
undersideØ48–Ø80 flat, 3 × Ø3.4 on r 28.5sleeve's top flange; M3 × 12clampla-frame-stator-top-plate*
posts3 × Ø8 × 5 on r 36, Ø2.5 tapped through post and plateseat ring underside; M3 × 16 (M3 tap drill)clampla-frame-stator-top-plate*
leaf seatannulus Ø47.5–Ø64 × 0.8leaf 2's Ø64 rim, clamped by the upper clamp ringclampla-frame-leaf-seat-ring*
holes3 × Ø3.4 on r 36M3 clearance (ISO 273 medium)designedla-frame-leaf-seat-ring*

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Xem Studiotools/gen_la_module.py: the module's geometry, masses, bounce volume, natural frequencies and every number on these pagescodeCC BY 4.0
Xem Studiotools/gen_fpse_gen.py: the free-piston generator whose stator, magnets, leaves and collars this module reuses; its leaf frame model and magnetic-circuit estimatecodeCC BY 4.0
ISO (via iTeh sample)ISO 2852 clamp liners: face profile and flange / groove diametersPDFstandard excerpt; dimensions are facts
ASMEBPE Bioprocessing Equipment (tube OD and wall, clamp fittings)standardASME; dimensions are facts verify
Long Earth SocietyEngine buildsweb, videoLES site

Free files

★ Free files 6 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json

la-frame-base-2in-ferruleframe base: 2 in ISO 2852 end-cap face (clamps on the 42 mm spool's ferrule with a Type B gasket and a standard clamp), Ø50.8 neck to 9.5, 45° cone to Ø80, flat top at 28 with the leaf-1 rim seat (annulus Ø47.5–Ø64 × 0.8), bore Ø47.5 through, 3 × M3 tapped (Ø2.5 × 7.5) on r 36STEP · STL
la-frame-leaf-clamp-ring-80-posts10lower leaf clamp ring with posts: Ø80 / Ø47.5 × 3 on leaf 1's rim, three Ø8 × 10 posts on r 36 carrying the stator sleeve, Ø3.4 through each postSTEP · STL
la-frame-stator-sleeve-48x66stator sleeve: bore Ø48.00 × 66 (the magnet carrier's running gap), Ø50.8 outside under the stator teeth, lower flange Ø80 × 5 with 3 × Ø3.4 on r 36, 45° cone to the Ø64 top flange (the bobbin's Ø65 bore passes over it), 3 × M3 tapped (Ø2.5 × 8) in the top on r 28.5STEP · STL
la-frame-stator-top-plate-80-posts5stator top plate with posts: Ø80 / Ø48 × 5, 3 × Ø3.4 on r 28.5 to the sleeve, three Ø8 × 5 posts on r 36, M3 tapped (Ø2.5) through post and plateSTEP · STL
la-frame-leaf-seat-ring-80leaf-2 seat ring: Ø80 / Ø47.5 × 4, rim seat annulus Ø47.5–Ø64 × 0.8 in the top face, 3 × Ø3.4 on r 36STEP · STL
la-frame-leaf-clamp-ring-80upper leaf clamp ring: Ø80 / Ø47.5 × 3 on leaf 2's rim, 3 × Ø3.4 on r 36STEP · STL

Plain text: sheet.txt · JSON: /api/geometry?object=linear-alternator-module-open-frame-2in

Linear alternator module open frame, 2 in: frame base, leaf seats, clamp rings, stator sleeve and top plate, isometric render of a generated part
Render of la-frame-stator-top-plate-80-posts5 from the free STEP; not to scale.

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Questions

Why an open frame?

Nothing hides the leaves: you can watch them flex, swap a leaf or a mass disc without opening a joint, and check the mover by hand. The back of the piston is simply at the room's pressure, which is what an unpressurised engine wants.

Can the leaves go into a spool joint instead?

Yes: the same leaves (Ø64 rim) clamp between two half gaskets in any 2 in spool-to-spool joint, as in the closed module. The frame's seats are drawn to the same rim and the same clamped radius, so a leaf behaves the same in either mount.