Information Age & Silicon Revolution (1960–1990)Industrial Robotics & Automation

Milacron Robot Toolchanger: Common Base, Pins, and Wedge Lock

US 4,512,709

Common Tool Bases, Kinematic Registration, and Slide-Ramp Retention

Inventor(s)Daniel M. Hennekes, Richard A. Kolde, David E. Suica

Grant DateApril 23, 1985

Filing DateJuly 25, 1983

LocationMorrow, Ohio; Ft. Thomas, Kentucky; Lebanon, Ohio

US 4,512,709 claims a robot-end-effector toolchanger whose housing admits a common tool base through a central opening, locates it on a two-pin/bushing pair, and uses an actuator-driven transverse slide to capture its retention member. The principal disclosed form uses a T-shaped member: when the slide shifts, bifurcated ramp faces bear on the T crossbar and prevent withdrawal; moving the aperture back into alignment permits separation. The grant claims two independent forms—the toolchanger itself and the robot-plus-toolchanger system—and two dependent refinements for head-and-stem and T-ramp geometry.

USPTO PDF

Engineering Analysis & Physical Principles

How It Works: Step-by-Step Mechanical & Physical Breakdown

A robot is programmable, but its wrist cannot do a new physical job until it has the appropriate physical tool. This patent makes the tool interface a repeatable mechanism: the robot carries an adapter; every candidate tool carries the same base. The base first lands on two locating pins, then its retention member passes through an open aperture. A linear actuator shifts the locking slide sideways so that the crossbar is captured by mating ramps. The legal scope is this organized housing–slide–retention–positioning combination, not the broad idea of swapping robot tools.

The Core Breakthrough Mechanism

The source describes an ordered geometric state machine, not a source-measured force calculation: an unloaded adapter has its aperture aligned; a base may enter only in that opening state; bushings seat on the cylindrical and diamond-profile pins; the T-member crossbar passes the aperture; and a transverse slide moves so its aperture is no longer aligned. In the Claim 4 form, the slide's bifurcated ramp surfaces meet ramps on the T crossbar, making withdrawal geometrically blocked. The live relation is deliberately Boolean: $\mathrm{captured}=\mathrm{basePresent}\land\mathrm{registered}\land\mathrm{slideLocked}\land\mathrm{TMember}$ ; it identifies the claimed engagement topology but does not fabricate actuator pressure, ramp angle, friction, clamp force, load capacity, or time.

Interactive Real-Time Physical Simulation

Drag to rotate · Scroll to zoom · Shared controls update the displayed modelDrag to rotate · Pinch to zoom · Shared controls update the displayed model

INITIALIZING THREE.JS WEBGL SIMULATION...

Host-Model Telemetry/Computed Readout

Registration and Slide-Ramp Capture

Engagement State

Source

captured t membersource topology[1]

Pin Registration

Source

seatedcylindrical + diamond[1]

Slide Aperture

Source

offsetretention path[1]

Quantitative Mechanics

Source Refusal

refusedno force / stroke / time data[1]

Tool base at adapter1 absent / present

Pin / bushing registration1 normalized state

Locking-slide position1 aligned → capture

Claim 4 T-member form1 generic → Claim 4

Detailed Component Architecture

1Adapter Housing and Central Opening

Spaced front and rear plates, joined by blocks, carry the robot-side housing; the front plate's central opening is the admission path for the tool-base retention member.

Claims 1 and 3 require a housing, paired rigidly connected plates, and the opening. The source locates a linear actuator between the plates and identifies the shown circular plates and rectangular spacer blocks. It provides no full dimensions, material, mass, stiffness, or robot-wrist pattern. The 2D and 3D forms are therefore source-shaped teaching diagrams, not a scaled replacement part.

19th-C. Term: housingModern: robot-side toolchanger adapter body

2Common Tool Base and Registration Pair

Each tool can carry the same base, whose bushings receive a cylindrical locating pin and a diamond-shaped locating pin before the lock moves.

The source says reception of bushings 42 on pins 43 and 44 assures accurate registration before clamping. A round/diamond pair is a practical way to constrain position while avoiding a redundant second round-pin fit. The patent does not print diameters, clearance, tolerance, compliance, or repeatability. Accordingly the visual exposes a registration state, not a numerical alignment claim.

19th-C. Term: toolbaseModern: standardized tool-side interface plate

3Linear Slideway and Aperture

A rod-driven linear slide crosses the front plate. Its aperture aligns with the central opening only in the admission/release position.

The slideway is transverse to the central opening, and Claims 1 and 3 make the slide's rod coupling and alignable aperture legal requirements. Shifting it is the key topological transition: when the aperture is offset, the inserted retention member cannot simply follow its original straight withdrawal path. The grant names extended and retracted end positions but gives no stroke or timing, so slider travel is normalized from 0 to 1.

19th-C. Term: slidewayModern: linear guide track

4T-Member, Clearance Slot, and Wedge Ramps

The preferred Claim 4 retention member has a narrow stem and a wider crossbar; the bifurcated slide leaves clearance for the stem while ramp faces bear on the crossbar.

The source calls the interaction a forked, clevis manner with a wedging action. The lock result is a capture geometry: the stem stays in the central slot while the slide ramps engage the crossbar ramps. The statement that the tool tends to remain locked after power failure is preserved as source language. Without ramp angle, lubrication, material, actuator force, load, shock, or back-drive data, the museum does not calculate a holding force or safety factor.

19th-C. Term: forked, clevis mannerModern: split-slide capture around a T-stem

5Actuator, Utility Passage, and Presence Switch

A fluid-powered linear actuator moves the yoke and locking slide; optional fluid or electrical connections can pass through an engaged tool base, while a proximity switch detects base presence.

The patent separates retention from utilities: some tools may have a fluid port, some an electrical connector, and some neither. The actuator's cylinder, piston rod, yoke, and the switch are named source parts, but their supply pressure, bore, flow, wiring, switching distance, controller, and cycle time are absent. The exhibit treats those as source-described options, not telemetry inputs.

19th-C. Term: interdrillingModern: internal drilled utility passage

Engineering Principles & Equations

Governing Equations & Engineering Principles

Authored explanation paired with its stated mathematical relation

Admission, Registration, and Claim 4 Capture State

Source-Bounded Toolchanger Topology

Mathematical Governing Law

\htmlClass{eq-term eq-term-captured eq-term-sapphire}{\htmlData{var=captured}{\textcolor{#2563eb}{\mathrm{captured}}}}=\htmlClass{eq-term eq-term-base_present eq-term-emerald}{\htmlData{var=base_present}{\textcolor{#059669}{\mathrm{basePresent}}}}\land\htmlClass{eq-term eq-term-registered eq-term-amber}{\htmlData{var=registered}{\textcolor{#d97706}{\mathrm{registered}}}}\land\htmlClass{eq-term eq-term-slide_locked eq-term-amethyst}{\htmlData{var=slide_locked}{\textcolor{#9333ea}{\mathrm{slideLocked}}}}\land\htmlClass{eq-term eq-term-t_member eq-term-crimson}{\htmlData{var=t_member}{\textcolor{#dc2626}{\mathrm{TMember}}}}

Terms:

Plain English DecoderHover or tap any highlighted phrase

The exhibit marks the tool as only after a , its bushings are , the , and the Claim 4 .

\mathrm{captured}

Claim 4 Capture State

Boolean source-topology state for the selected T-member/ramp form

true / false[1]

This is an authored teaching predicate, not a holding-force, reliability, or performance value.

Live Physical Value:

captured t member source topology

Physical Principle & Engineering Insight

The relation is a source-bound state predicate. US 4,512,709 supplies no pressure, bore, ramp angle, friction, actuator stroke, force, load, or timing input from which a wedge-force equation could honestly be evaluated.

Historical Context: The grant makes a durable industrial interface legible: locate a common base first, then capture its retention member through a controlled release path.

Geometric constraint and registrationAuthored Principle 1

Stated relation

$\mathrm{registered}=\mathrm{basePresent}\land\mathrm{bushingsOnPins}$

The equation is an editorial state relation that binds the live diagram to the source's stated order: the base is positioned on its pin-and-bushing pair before clamping. It is not a tolerance or stiffness equation, because the grant supplies none of the needed dimensions or material data.

Interference-based retentionAuthored Principle 2

Stated relation

$\mathrm{withdrawalBlocked}=\mathrm{slideOffset}\land\mathrm{crossbarCaptured}$

An aligned aperture admits the T-member; an offset slide brings its ramp surfaces into engagement with the wider crossbar. The intended lock is physical interference. This source-based relation says nothing about the magnitude of load the interface withstands.

Wedge contact requires missing data for a force resultAuthored Principle 3

Stated relation

$F_{axial}\ \text{is not evaluated}$

A wedge force calculation would require ramp angle, normal force, friction, actuator output, preload, material stiffness, and applied tool load. None are printed in the grant. The physics boundary therefore refuses a numerical clamp/holding-force display rather than assigning plausible values.

Interactive Schematic Sheet (1)

Source Figure 1: a robot wrist carries adapter 17 while distinct tools 19, each with common base 18, wait on rack 20.

1.00x

Click any numbered callout pin or use arrow keys [← / →]Tap any numbered pin3 Curated Callouts

Callout Pin Inspector

Select Any Numbered Pin

Click pins on the schematic or select from the list below to inspect historical specifications.

Why It Still Matters

Industrial automation often works through interfaces rather than a single universal hand: a robot needs a repeatable way to pick up a gripper, welding tool, fluid-powered fixture, or an unpowered tool at the wrist. This grant is a crisp teaching example because it separates three questions modern cells still confront—where the tool is located, how it is retained, and which utilities it needs—then makes the ramp-and-T capture visible without claiming unprinted performance.

Legal Claims Decoder (4 Numbered Claims)

Compare dense legalistic claims directly with decoded plain-English functional specifications.

Claim #1Independent Master Claim

1/4

Verbatim Historical Legal Text

“1. A robot toolchanger, comprising: (a) a housing, having spaced-apart front and rear plates rigidly connected to one another; (b) a central opening through said front plate; (c) a linear actuator mounted to said rear plate between said plates, and having a rod movable between extended and retracted end positions; (d) a linear slideway on said front plate, transverse to said central opening; (e) a locking slide carried in said slideway and affixed to said rod, said slide having an aperture alignable with said central opening, and further having means for engaging a tool retention member; (f) a toolbase having a tool retention member affixed thereto, said member insertable into said housing through said central opening and said slide aperture; (g) means for positioning said toolbase on said housing; and (h) means for positioning and securing said housing on a movable robot member.”

Plain English Engineering Translation

Claim 1 covers the toolchanger itself. It requires the rigid two-plate housing, central opening, actuator and rod, transverse slideway, locking slide with alignable aperture, tool base and its retention member, plus means to position the base and to secure the housing to a movable robot member. The slide is legally central: it must be carried in the guideway, attached to the rod, and able to engage the inserted retention member. A removable robot tool without that coordinated admission, slide, and positioning arrangement is not automatically the claimed combination.

Key Protected Innovations:

Two-plate adapter housingAlignable locking-slide apertureCommon tool base

Historical Legal Impact:

Independent apparatus claim defining the housing, opening, slide, retention member, and robot-side positioning combination.

The Historical Bottleneck

A programmable industrial robot may still be interrupted when a person must replace the physical tool at its wrist. The grant targets automatic selection, registration, retention, and release of multiple tool types on a common interface.

Why Prior Art Failed

•The specification says a robot generally carries one special tool for the immediate task, with changeover performed by a maintenance operator when work changes.
•A replaceable interface needs both accurate position before clamping and a retention scheme intended to remain in a terminal state after actuator power fails.

The Breakthrough Insight

“Separate tool choice from wrist mounting: use a shared base for several tools, a nonredundant locating-pin/bushing pair for registration, and a transverse aperture/ramp slide that converts admission into mechanical capture.”

After the Grant

The grant's own embodiment connects the adapter to the cited Stackhouse wrist and depicts multiple common-base tools in a rack. No patent-dispute record is asserted here because this archival packet did not establish one from primary legal evidence.

Civilizational Impact

The document makes a durable industrial-robotics problem unusually visible: automation has to exchange physical capability as well as move an arm. Its value in this archive is the inspectable interface logic—registration before capture, then a deliberate release path—not an unverified claim that this one grant created all modern toolchanging practice.

Further Context

The source depicts both fluid and electrical tool-side connections, but says some tools may need neither; utility transfer is optional rather than the core retention claim.
The patent calls one locating pin cylindrical and the other diamond-shaped in cross section; it does not print their dimensions or an alignment tolerance.