Brown movement 228 depicts a rimmed wheel with teeth entering rectangular chain openings. This oblique animation follows that arrangement with connected side members and crossbars. The calculator tracks chain advance and compares chain pitch with a separately entered wheel design pitch.
Chain and Pulley (form 2) Interactive Calculator
Set the link pitch, number of link advances per wheel turn and selected turns to calculate chain travel. Compare the wheel design pitch separately. The animation advances and returns through the selected turns using a matched reference chain and wheel.
Equation Used
- Rigid pitch links and a matched reference wheel for the animation.
- One link advance per defined engagement interval; N intervals per revolution.
- Advance and return are shown at an illustrative rate, not a selected drive speed.
- Round wire for the cross-section calculation; connector geometry is schematic.
- No manufactured pocket profile, tolerance limit, brake, reeving or load rating is determined.
Matched chain-wheel reference geometry based on Brown movement 228. A wheel-pitch mismatch is shown as a separate dimensional comparison; the animation does not force incompatible parts to mesh. Wire size is schematic in the oblique drawing. No pocket depth, chain strength or lifting capacity is calculated.
A rimmed wheel engaging chain openings
Brown movement 228 shows a chain running around a wheel viewed obliquely. Side plates flank the engagement region, with teeth entering the chain openings. The adjacent text identifies it as another chain-and-pulley arrangement.
The animation represents the visible chain as connected side members and crossbars. Link pitch remains fixed as each section enters the wrap, passes the wheel and exits. The front plate, rear plate and projecting shaft make the wheel’s depth visible.
The reference is not a dimensional production drawing. Link widths, connector shapes and tooth contours here are explanatory geometry.
Positive engagement and chain travel
The drawing illustrates how a wheel can transfer motion through chain openings. It is not a complete manual or electric hoist, and it does not show reduction gearing, a brake or a lifting hook.
The chain-travel calculator can compare a selected pitch and number of engagement intervals. Any conversion from chain travel to load travel requires the actual routing and number of supporting chain parts.
Count the individual link advances
Let p be link pitch, N the number of individual link advances per complete wheel turn, and rev the selected turns. Chain advance per turn is Np; Np·rev is the mean advance. For fractional turns, the illustrated pitch polygon includes chordal action: R = p/[2sin(π/N)], k = round(N·rev), and selected advance = kp + Rsin(2π·rev−2πk/N). Complete turns still give exactly Np per turn.
N is defined explicitly here as link advances, not an unspecified count of paired pockets. For a different wheel that advances two links per named pocket, its individual link count must be used instead.
The relative pitch difference is 100|pc−p|/p. It is a dimensional comparison, not a permissible mismatch or prediction of skipping. The animation uses a matched reference wheel at pitch p; a different pc is displayed separately.
For a round wire of diameter d, cross-sectional area is πd²/4. That quantity does not specify pocket depth or establish chain strength. Pocket dimensions require the complete chain-link and wheel geometry.
Default chain advance
With p = 18 mm and ten individual link advances per turn, the chain advances 180 mm per revolution. One selected revolution gives 180 mm total advance; two give 360 mm. These values describe chain motion, not an unspecified hoist’s hook travel.
A wheel design pitch of 18 mm matches the entered chain pitch. Changing it to 19 mm gives a 5.56% difference. The comparison reports the difference; the animation continues to show a matched reference chain and wheel.
A 6 mm round wire has cross-sectional area about 28.27 mm². This geometric result does not account for material, bends, welds, wear or loading.
Limits of the schematic
The source identifies the arrangement but supplies no calibrated chain standard, pocket tolerances or rated load. Those details cannot be inferred from an animation.
The chain reference uses rigid link segments with an illustrative projection. Polygonal engagement causes the entering and leaving spans to shift slightly. The programmed cycle reverses smoothly so selected travel can be inspected repeatedly.
Calculator questions
Is chain advance the same as hook lift?
Only for a specified one-part arrangement. Reeving can change the relationship; it is not modeled here.
What does the count input mean?
It counts individual link advances per complete wheel revolution. It does not assume every product uses the same pocket naming convention.
Why does the wheel still animate with a pitch mismatch?
The animation uses a matched reference wheel at the entered chain pitch. The separate wheel-pitch input changes the dimensional comparison; it does not alter the animated tooth engagement.
Does wire diameter determine pocket depth?
No. Wire diameter gives the round wire’s cross-sectional area. Pocket depth also depends on the full link and wheel geometry, which this calculator does not design.
References & Further Reading
- Henry T. Brown, Five Hundred and Seven Mechanical Movements, Cornell digitized copy, printed pages 58–59, movement 228: rimmed chain-wheel arrangement.
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