US 5,294,035 AGranted

Ratchet device having a stopper member for preventing excessive rotation of ratchet wheel, and tape feeding apparatus using the ratchet device

AssigneeFuji Machine Mfg. Co., Ltd.

InventorsKoichi Asai, Mamoru Tsuda, Shinsuke Suhara

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Abstract

A ratchet device is disclosed which includes a body, a ratchet wheel rotatably supported by the body, a feed pawl having an engaging portion engageable with teeth of the ratchet wheel, a support member for holding the feed pawl, a member for biasing the feed pawl toward the wheel teeth, and a drive device for moving reciprocating the support member between two positions to place the feed pawl alternately in its fully advanced and retracted positions, so as to rotate the ratchet wheel a predetermined angle in one direction. The ratchet device further includes a stopper member for contact with the feed pawl when the pawl is placed in the fully retracted position, to thereby prevent the engaging portion of the pawl from disengaging from the teeth of the ratchet wheel. Further, the engaging portion of the feed pawl is shaped so that it engages mutually opposed faces of the ratchet wheel when the feed pawl is in contact with the stopper member, to thereby lock the ratchet wheel against clockwise and counterclockwise rotations thereof. Also disclosed is a tape feeding apparatus which utilizes the ratchet device.

Claims21

Dependent claims

An apparatus for feeding a carrier tape, which has electronic components spaced apart from each other in a longitudinal direction of the carrier tape, said carrier tape having equi-spaced feed holes arranged in said longitudinal direction, said apparatus comprising:

a body;
a sprocket wheel rotatably supported by said body and having a plurality of teeth engageable with said feed holes of said carrier tape;
a ratchet wheel rotatably supported by said body and having a plurality of teeth, said ratchet wheel being connected to said sprocket wheel, for rotating said sprocket wheel;
a feed pawl having an engaging portion engageable with said teeth of said ratchet wheel;
a support member movably supported by said body, for movably holding said feed pawl such that said engaging portion is movable in a direction toward and away from said teeth of said ratchet wheel;
biasing means for biasing said feed pawl toward said teeth of said ratchet wheel for engagement of said engaging portion with said teeth;
drive means for moving said support member between a first portion for placing said feed pawl in a fully advanced position, and a second position for placing said feed pawl in a fully retracted position, said engaging portion of said feed pawl passing at least one of said teeth of said ratchet wheel when said support member is moved from said second position to said first position, and rotating said ratchet wheel in one direction by a predetermined angle corresponding to the number of said at least one of said teeth, while engaging a last tooth of said at least one of said teeth which said feed pawl has passed last, when said support member is moved form said first position to said second position;
a stationary rigid stopper member formed integrally with said body, and having a stopper surface for contact with said feed pawl when said support member is moved to said second position, for preventing said engaging portion of said feed pawl from disengaging from said last tooth of said ratchet wheel;
and
said engaging portion of said feed pawl being shaped so that the engaging portion engages mutually opposed tooth faces of said ratchet wheel when said feed pawl is held in contact with said stopper surface, to thereby lock said ratchet wheel against clockwise and counterclockwise rotations thereof.

7 more elements

An apparatus for feeding a carrier tape which has electronic components spaced apart from each other in a longitudinal direction of the carrier tape, said carrier tape having equi-spaced feed holes arranged in said longitudinal direction, said apparatus comprising:

a body;
a sprocket wheel rotatably supported by said body and having a plurality of teeth engageable with said feed holes of said carrier tape;
a ratchet wheel rotatably supported by said body and having a plurality of teeth, said ratchet wheel being connected to said sprocket wheel, for rotating said sprocket wheel;
a feed pawl having an engaging portion engageable with said teeth of said ratchet wheel, and being pivotable about a pawl axis parallel to a wheel axis of said ratchet wheel;
a pivotable lever supported by said body pivotally between a first position for placing said feed pawl in a fully advanced position and a second position for placing said feed pawl in a fully retracted position, about a lever axis parallel to said pawl axis of said feed pawl, and connected to said feed pawl such that said engaging portion is movable in a direction toward and away from said teeth of said ratchet wheel;
biasing means for biasing said feed pawl toward said teeth of said ratchet wheel for engagement of said engaging portion with said teeth;
drive means comprising (a) a drive plate pivotally connected at one of opposite ends thereof to said pivotable lever, (b) a drive source connected to the other end of said drive plate, for moving said drive plate in a direction substantially parallel to a feeding direction of said carrier tape, for pivoting said pivotable lever from said second position to said first position, to thereby move said feed pawl to said fully advanced position, so that said engaging portion of said feed pawl passes at least one of said teeth of said ratchet wheel when said support member is moved from said second position to said first position, and (c) a spring member for biasing said pivotable lever toward said second position, to thereby return said feed pawl to said fully retracted position so that said ratchet wheel is rotated in one direction by a predetermined angle corresponding to the number of said at least one of said teeth, while engaging a last tooth of said at least one of said teeth which said feed pawl has passed last;
a stopper member provided on said body, for contact with said feed pawl when said pivotable lever is placed in said second position, for preventing said engaging portion of said feed pawl from disengaging from said last tooth of said ratchet wheel;
and
said engaging portion of said feed pawl being shaped so that the engaging portion engages mutually opposed tooth faces of said ratchet wheel when said feed pawl is held in contact with said stopper member, to thereby lock said ratchet wheel against clockwise and counterclockwise rotations thereof.

7 more elements

a body;
a sprocket wheel rotatably supported by said body and having a plurality of teeth engageable with said feed holes of said carrier tape;
a ratchet wheel rotatably supported by said body and having a plurality of teeth, said ratchet wheel being connected to said sprocket wheel, for rotating said sprocket wheel;
a feed pawl having an engaging portion engageable with said teeth of said ratchet wheel, and being pivotable about a pawl axis parallel to a wheel axis of said ratchet wheel;
a pivotable lever supported by said body pivotally between a fist position for placing said feed pawl in a fully advanced position and a second position for placing said feed pawl in a fully retracted position, about a lever axis parallel to said pawl axis of said feed pawl, and connected to said feed pawl such that said engaging portion is movable in a direction toward and away from said teeth of said ratchet wheel;
biasing means for biasing said feed pawl toward said teeth of said ratchet wheel for engagement of said engaging portion with said teeth;
drive means comprising (a) a drive plate pivotally connected at one of opposite ends thereof to said pivotable lever, (b) a drive bar pivotally supported by said body and connected to the other end of said drive plate, for moving said drive plate in a direction substantially parallel to a feeding direction of said carrier tape, for pivoting said pivotable lever from said second to said first position, to thereby move said feed pawl to said fully advanced position, so that said engaging portion of said feed pawl passes at least one of said teeth of said ratchet wheel when said pivotable lever is pivoted from said second position to said first position, and (c) a spring member for biasing said pivotable lever toward said second position, to thereby return said feed pawl to said fully retracted position so that said ratchet wheel is rotated in one direction by a predetermined angle corresponding to the number of said at least one of said teeth, while engaging a last tooth of said at least one of said teeth which said feed pawl has passed last;
means for selecting one of a plurality of pivot axes about which said drive bar is pivoted, said plurality of pivot axes being spaced from each other in a longitudinal direction of said drive bar so that a pivoting angle of said pivotable lever and said predetermined angle of rotation of said ratchet wheel are changed depending upon a selected one of said pivot axes;
a stopper member provided on said body, for contact with said feed pawl when said pivotable lever is placed in said second position, for preventing said engaging portion of said feed pawl from disengaging from said last tooth of said ratchet wheel;
and
said engaging portion of said feed pawl being shaped so that the engaging portion engages mutually opposed tooth faces of said ratchet wheel when said feed pawl is held in contact with said stopper member, to thereby lock said ratchet wheel against clockwise and counterclockwise rotations thereof.

8 more elements

Dependencies are inferred from the claim text.