Low-impact four-bar press

Claim 2

A press including: a frame, a slide member carried by said frame for reciprocable movement along a path between first and second positions, drive means for reciprocating said slide member between said first and second positions, said drive means including a first link member having first and second end portions with the first end portion pivotally connected to said slide member, a crank member rotatably mounted in said frame, a connecting link member having opposite end portions pivotally connected respectively to said crank member and the second end portion of said first link member, and a constraining link member having a first end portion pivotally connected to said frame intermediate said path and the axis of said crank and a second end portion pivotally connected to said connecting link member intermediate said opposite end portions thereof.

Claim 3

The press as defined in claim 1, wherein said first end portion of said constraining link member is pivotally connected to said frame on an axis spaced below said axis of said crank member.

Claim 4

The press as defined in claim 1, and a second constraining link member parallel to said first constraining link member.

Claim 5

The press as defined in claim 1, wherein said first end portion of said constraining link member is pivotally connected to said frame at a point intermediate said axis of said crank member and the adjacent end of said path.

Claim 6

The press as defined in claim 1, wherein the angle between said constraining link member and said connecting link member is at least 40* at all times during rotation of said crank member 360*.

Claim 7

The press as defined in claim 1, wherein the distance between the pivot axis of said crank member and connecting link member and the pivot axis of said connecting link member and constraining link member is more than three times the distance between the pivot axis of said connecting link member and constraining link member and the pivot axis of said connecting link member and said first link member.

Claim 8

The press as defined in claim 6, wherein the distance between the pivot axes at opposite ends of said constraining link member is more than twice the distance between the pivot axis of said crank member and frame and the pivot axis of said crank member and connecting liNk member.

Claim 9

The press as defined in claim 7, wherein the distance between the pivot axis of said crank member and connecting link member and the pivot axis of said connecting link member and constraining link member is approximately twice the distance between the pivot axis of said crank member and frame and pivot axis of said crank member and connecting link member.

Claim 10

In a power press comprising a frame, a slide member carried by said frame for reciprocable movement along a substantially straight slide path between first and second positions relative to said frame, and a linkage drive means for reciprocating said slide member between said first and second positions, the improvement comprising: said linkage drive means including a first link having first and second end portions with said first end portion pivotally connected to said slide at a first axis, a crank member rotatably mounted on said frame at a second axis, a second link having one end thereof pivotally connected to said crank member at a third axis spaced from said second axis and having the other end thereof pivotally connected to said second end portion of said first link at a fourth axis, and a third link having one end thereof pivotally connected to said frame at a fifth axis and the other end thereof pivotally connected to said second link at a sixth axis, said sixth axis being spaced from said third and fourth axes and being closer to said fourth axis than said third axis, said fourth axis defining a generally elliptical coupler path when said crank member is rotated 360* about said second axis, said coupler path having a major axis defined by the longest line between two points inside said coupler path, said major axis extending generally transversely of said slide path.

Claim 11

In a power press comprising a frame, a slide member carried by said frame for reciprocable movement along a substantially straight slide path between first and second positions relative to said frame, and a linkage drive means for reciprocating said slide member between said first and second positions, the improvement comprising: said linkage drive means including a first link having first and second end portions with said first end portion pivotally connected to said slide at a first axis, a crank member rotatably mounted on said frame at a second axis, a second link having one end thereof pivotally connected to said crank member at a third axis spaced from said second axis and having the other end thereof pivotally connected to said second end portion of said first link at a fourth axis, and a third link having one end thereof pivotally connected to said frame at a fifth axis and the other end thereof pivotally connected to said second link at a sixth axis, said sixth axis being spaced from said third and fourth axes and being closer to said fourth axis than said third axis, said fourth axis defining a generally elliptical coupler path when said crank member is rotated 360* about said second axis, said coupler path having a major axis defined by the longest line between two points inside said coupler path, said major axis extending generally transversely of said slide path.

Claim 12

The press as defined in claim 9, wherein said coupler path includes portions disposed on opposite sides of said slide path.

Claim 13

The press as defined in claim 9, wherein the angle between said second link and said third link is at least 40* at all times during rotation of said crank member.

Claim 14

The press as defined in claim 11, wherein the distance between said third and sixth axes is more than three times the distance between said sixth and fourth axes.

Claim 15

The press as defined in claim 12, wherein the distance between said fifth and sixth axes is more than twice the distance between said second and third axes.

Claim 16

The press as defined in claim 13, wherein the distance between said third and sixth axes is approximately twice the distance between said second and third axes.

Claim 17

The press as in claim 10, wherein said slide path substantially bisects said major axis of said coupler path.

Claim 18

A power press comprising a frame, a slide member carried by said frame for reciprocable movement along a generally straight path between first and second positions relative to said frame, and a linkage drive means for reciprocating said slide member between said first and second positions with a predetermined velocity-time relationship, said linkage drive means including a first link member having first and second end portions with said first end portion pivotally connected to said slide at a first axis, a crank member rotatably mounted on said frame at a second axis, a second link member pivotally connected at one end thereof to said crank member at a third axis and pivotally connected to the second end portion of said first link member at a fourth axis, and a third link member having one end thereof pivotally connected to said frame at a fifth axis and a second end pivotally connected to said second link member at a sixth axis, said sixth axis being spaced from said third and fourth axes and being closer to said fourth axis than said third axis, said slide member moving from said one position thereof through said second position and back to said one position thereof in response to rotation of said crank member 360* about said second axis, said third link member constraining said fourth Axis to follow a generally elliptical coupler path in response to rotation of said crank member, said coupler path having a major axis defined by the longest distance between two points within said path, said major axis extending substantially transverse to said slide path, said movement of said fourth axis along said coupler path being definitive of movement of said slide from said first position through said second position and back to said first position thereof in a manner whereby said slide member moves with high velocity during a substantial portion of movement thereof and at a much lower velocity during the remaining portion of the movement thereof.

Claim 19

A power press comprising a frame, a slide member carried by said frame for reciprocable movement along a generally straight path between first and second positions relative to said frame, and a linkage drive means for reciprocating said slide member between said first and second positions with a predetermined velocity-time relationship, said linkage drive means including a first link member having first and second end portions with said first end portion pivotally connected to said slide at a first axis, a crank member rotatably mounted on said frame at a second axis, a second link member pivotally connected at one end thereof to said crank member at a third axis and pivotally connected to the second end portion of said first link member at a fourth axis, and a third link member having one end thereof pivotally connected to said frame at a fifth axis and a second end pivotally connected to said second link member at a sixth axis, said sixth axis being spaced from said third and fourth axes and being closer to said fourth axis than said third axis, said slide member moving from said one position thereof through said second position and back to said one position thereof in response to rotation of said crank member 360* about said second axis, said third link member constraining said fourth Axis to follow a generally elliptical coupler path in response to rotation of said crank member, said coupler path having a major axis defined by the longest distance between two points within said path, said major axis extending substantially transverse to said slide path, said movement of said fourth axis along said coupler path being definitive of movement of said slide from said first position through said second position and back to said first position thereof in a manner whereby said slide member moves with high velocity during a substantial portion of movement thereof and at a much lower velocity during the remaining portion of the movement thereof.

Claim 20

The press as defined in claim 16, wherein the distance between said third and sixth axes is more than three times the distance between said sixth and fourth axes.

Claim 21

The press as defined in claim 17, wherein the distance between said fifth and sixth axes is more than twice the distance between said second and third axes.

Claim 22

The press as defined in claim 18, wherein the distance between said third and sixth axes is approximately twice the distance between said second and third axes.

Claim 23

A power press comprising a frame, a slide member carried by said frame for reciprocable movement along a generally straight path the length of which defines a stroke and which stroke includes a return and advance portion and a working portion, and a linkage drive means for reciprocating said slide member through said return and advance portion and said working portion, said linkage drive means including a first link member having one end thereof pivotally connected to said slide member, a crank member rotatably mounted on said frame and having a crank arm rotatable about the axis of said crank member, a second link member having one end thereof pivotally connected to the second end of said first link member and having the other end thereof pivotally connected to said crank arm on an axis spaced from said crank axis, and a constraining link member having one end thereof pivotally connected to said frame and the other end thereof pivotally connected to said link member at a point intermediate the opposite ends of said second link member, said slide member moving through said stroke thereof in response to rotation of said crank member 360*, said constraining link member operating during rotation of said crank member to constrain movement of said slide member through said stroke thereof in a manner whereby said return and advance portion of said stroke is at a higher velocity than said working portion of said stroke.

Claim 24

A power press comprising a frame, a slide member carried by said frame for reciprocable movement along a generally straight path the length of which defines a stroke and which stroke includes a return and advance portion and a working portion, and a linkage drive means for reciprocating said slide member through said return and advance portion and said working portion, said linkage drive means including a first link member having one end thereof pivotally connected to said slide member, a crank member rotatably mounted on said frame and having a crank arm rotatable about the axis of said crank member, a second link member having one end thereof pivotally connected to the second end of said first link member and having the other end thereof pivotally connected to said crank arm on an axis spaced from said crank axis, and a constraining link member having one end thereof pivotally connected to said frame and the other end thereof pivotally connected to said link member at a point intermediate the opposite ends of said second link member, said slide member moving through said stroke thereof in response to rotation of said crank member 360*, said constraining link member operating during rotation of said crank member to constrain movement of said slide member through said stroke thereof in a manner whereby said return and advance portion of said stroke is at a higher velocity than said working portion of said stroke.

Claim 25

The press as defined in claim 20, wherein said end of said constraining link pivotally connected to said frame is connected to said frame at a point intermediate the path of said slide and the axis of said crank member.

Claim 26

The press structure as defined in claim 21, wherein said constraining link pivot point is disposed below said axis of said crank member.

Claim 27

The press of claim 22, wherein said constraining link constrains the pivot axis between said first and second link members to follow a generally elliptical coupler path definitive of high velocity return and advance portions of said stroke and low velocity work portion of said stroke.

Claim 28

The press structure as defined in claim 22, wherein the angle between said second and third link members is greater than 40* at all times during rotation of said crank member 360*.

Claim 29

The press as defined in claim 24, wherein the distance between the pivot axis of said crank member and connecting link member and the pivot axis of said connecting link member and constraining link member is more than three times the distance between the pivot axis of said connecting link member and constraining link member and the pivot axis of said connecting link member and said first link member.

Claim 30

The press as defined in claim 25, wherein the distance between the pivot axes at opposite ends of said constraining link member is more thaN twice the distance between the pivot axis of said crank member and frame and the pivot axis of said crank member and connecting link member.

Claim 31

The press as defined in claim 26, wherein the distance between the pivot axis of said crank member and connecting link member and the pivot axis of said connecting link member and constraining link member is approximately twice the distance between the pivot axis of said crank member and frame and the pivot axis of said crank member and connecting link member.

Claim 32

In a low-impact metal cutting power press comprising a frame, a slide member carried by said frame for reciprocable movement along a generally straight path the length of which defines a stroke for the slide member and which stroke includes a short working portion and a relatively longer return and advance portion, the improvement which comprises: a linkage drive means for reciprocating said slide member through said working portion at a low velocity to achieve low-impact force between a tool carried by said slide member and a workpiece engaged by said tool during said work portion of said stroke, said linkage drive means including a first link member having one end thereof pivotally connected to said slide member, a crank member rotatably mounted on said frame and having a crank arm rotatably 360* about the axis of said crank member, a second link member having one end thereof pivotally connected to the other end of said first link member and having the other end thereof pivotally connected to said crank arm on an axis spaced from said crank axis, and a constraining link member having one end thereof pivotally connected to said frame and the other end thereof pivotally connected to said second link member at a point intermediate the opposite ends of said second link member, said constraining link member operating during rotation of said crank member to constrain movement of said slide member through the stroke thereof so that said slide member moves through said work portion of said stroke at a low velocity to achieve low-impact force between said tool and workpiece.

Claim 33

In a low-impact metal cutting power press comprising a frame, a slide member carried by said frame for reciprocable movement along a generally straight path the length of which defines a stroke for the slide member and which stroke includes a short working portion and a relatively longer return and advance portion, the improvement which comprises: a linkage drive means for reciprocating said slide member through said working portion at a low velocity to achieve low-impact force between a tool carried by said slide member and a workpiece engaged by said tool during said work portion of said stroke, said linkage drive means including a first link member having one end thereof pivotally connected to said slide member, a crank member rotatably mounted on said frame and having a crank arm rotatably 360* about the axis of said crank member, a second link member having one end thereof pivotally connected to the other end of said first link member and having the other end thereof pivotally connected to said crank arm on an axis spaced from said crank axis, and a constraining link member having one end thereof pivotally connected to said frame and the other end thereof pivotally connected to said second link member at a point intermediate the opposite ends of said second link member, said constraining link member operating during rotation of said crank member to constrain movement of said slide member through the stroke thereof so that said slide member moves through said work portion of said stroke at a low velocity to achieve low-impact force between said tool and workpiece.

Claim 34

The improvement of claim 28, wherein said end of said constraining link pivotally connected to said frame is connected to said frame at a point intermediate the path of said slide and the axis of said crank member.

Claim 35

The improvement of claim 29, wherein said constraining link pivot axis is disposed below said axis of said crank member.

Claim 36

The improvement of claim 30, wherein said constraining link constrains the pivot axis between said first and second link members to follow a generally elliptical coupler path definitive of high velocity return and advance portions of said stroke and a low velocity work portion of said stroke.

Claim 37

The improvement of claim 31, wherein the angle between said second and constraining link members is greater than 40* at all times during rotation of said crank member 360* .

Claim 38

The improvement of claim 32, wherein said angle is at least 45* at all times during rotation of said crank member.

Claim 39

The press as defined in claim 2, wherein said axes of said crank member and said constraining link member are spaced apart along a line which intercepts said path of said slide member at an angle of approximately 139.5* .

Claim 40

The press as defined in claim 22, wherein said axis of said crank member and said pivot point of said constraining link are spaced apart along a line which intercepts said path of said slide member at an angle of approximately 139.5* .

Claim 41

The improvement of claim 30, wherein said axes of said crank member and constraining link are spaced apart along a line which intercepts said path of said slide at an angle of approximately 139.5* .