Parallel mechanism

Claim 2

Apparatus for maintaining a first movable member at a predetermined angle with respect to a reference surface when moved toward and away from the reference surface, the apparatus comprising, in combination with said first movable member: a pair of substantially identical legs arranged in reversed relationship and crossing over each other, each of said legs having a first end portion operably engageable with and movable along the reference surface, each of said legs also having a second end portion; means pivotally connecting the second end portions of said legs to said first member; guide means movable with respect to the first member, said guide means having a portion pivotally carrying said legs providing a pivotal connection between said legs and defining a crossover position thereof at a point between said first and second end portions of said legs; and means secured to said first member cooperating with said guide means to limit movement of the guide means in a generally linear direction.

Claim 3

The apparatus of claim 1 including spring means acting upon the guide means providing a pivotal connection between said legs, said spring means urging said pivotal connection in a direction generally normal to the reference surface.

Claim 4

The apparatus of claim 1 wherein: the portion of said guide means has spaced guide surfaces; each of said legs has a third portion disposed on said guide surfaces, said third portion being intermediate the first and second end portions, said third portions having means providing a pair of oppositely disposed rolling surfaces together having a dimension substantially equal to the surface between said guide surfaces on said guide member; and said legs are disposed in generally parallel, closely spaced relationship, each with its rolling surfaces disposed between said spaced guide surfaces on said guide member, said rolling surfaces and said guide surfaces together providing a pivot for said legs.

Claim 5

Apparatus for maintaining a first movable member at a predetermined angle with respect to a reference surface when moved toward and away from the reference surface, the apparatus comprising, in combination: a first movable member having a generally rectangular frame and means providing a pair of spaced, generally parallel work surfaces, and spaced generally parallel end members connecting said work surfaces; a pair of legs disposed adjacent each of said end members, each pair of legs arranged in reverse relationship and crossing over each other, each of said legs having a first end portion operably engageable with and movable along the reference surface and a second end portion, means pivotally connecting the second end portion to the end member adjacent thereto, guide means providing a pivotal connection between said pairs of legs and defining a crossover poSition thereof at a point between said first and second end portions of said legs, a pair of substantially identical housing members, one cooperable with each of the end members to provide an enclosure at each end of the device; said guide means at each end of said device being disposed within said enclosures and movable therein generally normal to said work surfaces; said guide means providing the pivotal connection between said legs whereby the pivot therebetween is movable generally normal to said work surfaces.

Claim 6

Apparatus for maintaining a first movable member at a predetermined angle with respect to a reference surface when moved toward and away from the reference surface, the apparatus comprising, in combination: a first movable member having a generally rectangular frame and means providing a pair of spaced, generally parallel work surfaces, and spaced generally parallel end members connecting said work surfaces; a pair of legs disposed adjacent each of said end members, each pair of legs arranged in reverse relationship and crossing over each other, each of said legs having a first end portion operably engageable with and movable along the reference surface and a second end portion, means pivotally connecting the second end portion to the end member adjacent thereto, guide means providing a pivotal connection between said pairs of legs and defining a crossover poSition thereof at a point between said first and second end portions of said legs, a pair of substantially identical housing members, one cooperable with each of the end members to provide an enclosure at each end of the device; said guide means at each end of said device being disposed within said enclosures and movable therein generally normal to said work surfaces; said guide means providing the pivotal connection between said legs whereby the pivot therebetween is movable generally normal to said work surfaces.

Claim 7

The apparatus of claim 4 including means cooperable between said guide means and said end members and limiting the relative movement between said guide means and the adjacent end member.

Claim 8

The apparatus of claim 4 further including spring means disposed within each of said enclosures and acting upon the guide means therein to urge the guide means, and thereby the pivot between the legs of each pair, in a given direction.

Claim 9

The apparatus of claim 4 wherein: said end members are substantially identical and are disposed in spaced, generally parallel, reversed relationship and are connected by a pair of spaced, generally parallel, substantially identical, members providing the work surfaces; each of said end members and its cooperating housing member includes means providing the pivotal connection between the second end portions of said legs and said first member; the structure providing two substantially identical end structures connected by said work surfaces, said end structures being disposed in generally aligned and reversed relationship; means connecting the first end portions of the aligned ones of said legs at opposition ends of the device whereby the first end portion of the first one of the legs at a first end of the device is relatively rigidly connected to, and moves with, the first end of the aligned leg at the opposite end of the device, and the first end of the second leg at said first end of the device is relatively rigidly connected to, and moves with, the first end of the aligned leg at the opposite end of the device.

Claim 10

The apparatus of claim 6 further including means operably connected to said spring means and manually movable to selectively vary the tension on said spring and thereby the force urging said pivot point between said legs in its given direction.

Claim 11

The apparatus of claim 4 further including motion-limiting means cooperable with the means providing a pivot point between the legs of a given pair and in adjustable abutting relationship therewith to limit the movement of said pivot point in a given direction; and means for manually operating said limiting means to select the limit of movement of said pivot point.

Claim 12

Paralleling apparatus comprising: movable means including a generally boxlike structure including a pair of spaced, generally parallel, longitudinal members having a pair of work surfaces thereon and a pair of spaced, generally parallel, end members connecting opposite ends of said longitudinal members, said end members comprising two substantially identical members each having a main portion and being generally symmetrical about a line which is generally normal to said longitudinal members, each of said members having offset to one side of said centerline a portion providing an annular bearing member extending a first predetermined distance from the main portion and a second, symmetrically disposed, annular portion extending a second predetermined distance, greater than the first, from said main portion and providing a second bearing member spaced further therefrom than said first bearing member; two pairs of generally flat leg members, one of said pairs disposed at each end of the device, each of the leg members having an opening for accepting one of said annular bearing members, one of the leg members of each pair being pivotally mounted on the first bearing member and the second of the leg members of said pair being mounted on the second of said bearing members, whereby said leg members of each pair are disposed in relatively closely spaced, generally parallel positions, said leg members having opposite ends extending from the pivot points and operably engageable with a reference surface; a pair of housing members, one cooperable with each of said end members to enclose at least a portion of the leg members connected thereto; means connecting said housing members to said end members; and said housing members including abutment means cooperable with said leg members to maintain said leg members mounted on their respective bearing members.

Claim 13

Paralleling apparatus comprising: movable means including a generally boxlike structure including a pair of spaced, generally parallel, longitudinal members having a pair of work surfaces thereon and a pair of spaced, generally parallel, end members connecting opposite ends of said longitudinal members, said end members comprising two substantially identical members each having a main portion and being generally symmetrical about a line which is generally normal to said longitudinal members, each of said members having offset to one side of said centerline a portion providing an annular bearing member extending a first predetermined distance from the main portion and a second, symmetrically disposed, annular portion extending a second predetermined distance, greater than the first, from said main portion and providing a second bearing member spaced further therefrom than said first bearing member; two pairs of generally flat leg members, one of said pairs disposed at each end of the device, each of the leg members having an opening for accepting one of said annular bearing members, one of the leg members of each pair being pivotally mounted on the first bearing member and the second of the leg members of said pair being mounted on the second of said bearing members, whereby said leg members of each pair are disposed in relatively closely spaced, generally parallel positions, said leg members having opposite ends extending from the pivot points and operably engageable with a reference surface; a pair of housing members, one cooperable with each of said end members to enclose at least a portion of the leg members connected thereto; means connecting said housing members to said end members; and said housing members including abutment means cooperable with said leg members to maintain said leg members mounted on their respective bearing members.

Claim 14

The apparatus of claim 10 further including means operably connecting and providing a pivotal connection between the two leg members of each pair at a point intermediate their pivot points on said end member and the opposite ends of said leg members, the means providing this pivotal connection being movable with respect to the adjacent end member in a direction generally normal to the longitudinal members.

Claim 15

The apparatus of claim 11 wherein the means providing a pivotal connection between the two leg members of a given pair comprises a guide member disposed within the housing member, intermediate said housing member and the adjacent end member, said guide member being movable with respect to said end member and housing member in a direction generally normal to the work surfaces provided by said longitudinal members; and the apparatus includes means limiting the movement of said guide members with respect to said end members and housing members in said direction.

Claim 16

The apparatus of claim 12 further including means disposed within said housing member and acting upon said guide member and resiliently urging said guide member in a given direction along its line of movement; and means cooperable with said resilient means and manually operable to selectively vary the force exerted by said resilient means on said guide member.

Claim 17

The apparatus of claim 11 further including means generally parallel to said longitudinal members and connecting the aligned opposite ends of said leg members at opposite ends of the device whereby aligned opposite legs of the device are substantially rigidly connected and the opposite aligned legs move substantially as a unit.

Claim 18

The apparatus of claim 12 further including eccentric cam means disposed within each of the housing members and in abutting relationship with said guide means to limit the movement of said guide means with respect to said housing and end members; and means rotatably mounting said eccentric cam means whereby said cam means may be selectively angularly positioned to determine the limits of movement of said guide members; and detent means coacting between said cam means and the adjacent housing member to define predetermined angular positions of said cam means.

Claim 19

The apparatus of claim 10 wherein said housing members are substantially identical and each includes a main surface spaced from the main portion of the adjacent end member; and said abutment means includes a pair of extending abutment portions on each of said housing members and aligned with the extending bearing members of the cooperating end member, the abutment portion extending toward the shorter of said bearing members being longer than the abutment portion extending toward the longer of said bearing members whereby said abutment portions extend substantially to the surface of the leg members mounted upon the respective bearing members and maintain the leg members mounted on their respective bearing members.