US1728506A - Guard for sewing-machine loop takers - Google Patents

Description

Sept. 17, 1929. w. N. PARKES GUARD FOR SEWING MACHINE LOOP TAKERS Fild Aug. 11. l1927 INVENTOR Wzl/zam MPareJ BKZ (AA ORNY wmmss y. 73m

Patented Sept, 17, 1929 lunirse STATES PATENT OFFICE WILLIAM NnLsoN imaxes, on BROOKLYN, NEW YORK, Assre-Non To THE SINGER MANUFACTURING COMPANY, kOI" ELIZABETH, NEW JERSEY, ACOBCLORATION OF NEW JERSEY` GUARD FOR SEWING-MACHINE LOOP. TAKERS Application led Augustr 11; 192i?. Serial No.k 212,173.

This invention relates to improvements in sewing machines of the type employing a loop-taker to cas-t needle-thread loops around a mass of under-thread in the formation of lock-stitches.`

During the operation of a threaded sewing machine of this'rtype in the absence of work, commonly termed chaining off,77 the chain of thread thus formed is liable to sag into the path of movement of the looptaker beak and is therefore likely to become jammed in the loop-taker racewayl for the bobbin-carrier.

The present invention has for its primary object to provide means for preventing the thread-chain from being fouled by the looptaker. A further object of this invention is to provide improved means external to the loop-taker for insuring a rapid spreading of the needle-thread loop toward the throat of the loop-taker beak or loop-seizing hook at the beginning of the movement of said beak to cast the needle-thread loopabout a mass of under-thread.

The present improvement has been embodied in a sewing machine having a looptaker of the vertical-axis type, in which the loop-taker beak has a horizontal path of m0- tion directly beneath the cloth-plate of the machine. .ln its preferred embodiment, the improvement comprises a horizontally disposed, segmental guard-finger overlying that portion of the loop-taker beak path first traversed after seizure of the needle-thread loop by said beak. The guard-finger is adjustably secured upon the machine frame below the cloth-plate and its shank portion is provided with a needle clearance notch, one wall of said notch constituting a stationary abutment for hastening the eXpansion of the loop by detaining the junction of its limbs while the loop is beingl distended by the loop-taker beak.

In the accompanying drawings, Fig. l is a substantially central, longitudinal section, partly in elevation, of a portion of a sewing machine cloth-plate and its attached looptaker mechanism bracket and showing the usual reciprocatory needle at substantially the lower end of its stroke. Fig. 2 is a top plan kview; of the same portion of the clothplate, buty omitting the throat-plate, slide" plates and the feed-dog. Fig. `3 is a detail .perspective view ofthe guard-finger. Certain featuresI of this loop-taker'mechanism are shown more in detail in myv application Serial No. herewith.y

' Referring to the drawings, the present 1 improvement is shown as embodied in a sewing machine having the usual bed orclothplate l, the throat-plateQ and tliefslideplates 3 and 4 at thelopposite'sides of the throat-plate. openings in the throat-plate `are the feeddog 5 and the reciprocatory needle 6.

' Suitably secured'to the underside of the bed-plate l is the loop-taker bijacket 7 sus- 212,172 filedy simultaneously Operating through suitable.

tainingthe loop-taker mechanism in its asl' sembled form as a detachable unit.r Journaled in said bracket 7 is the forward end of the rloop-taker actuating shaft 8, which rotates once yfor each complete reciprocation .of the'needle. l The actuating mechanism for the needle and the shaft 8 may compriseany usual, properly timed construction. such as is illustrated, for instance, in the United States patent to J.C.-Ringe, No. 1,484,191,

.fda-ted Feb. 19, 1924. Also journaled in the bracket. 7 is the vertically disposed looptaker shaft 9y geared to the shaft 8 to derive two rotations for each rotation of said shaft 8. Secured upon the upper end of the shaft 9 is a horizontally rotating looptaker 10 having a loop-seizing beak 1l. It ywill be observed from Fig. l of the drawings that the point of the beak 1l is located at they upper rim of the `loop-taker body and that it isdirectly below the throate0 provi( ed a segmental guard-linger lil, ont of Contact with but directly overlying that portion of the loop-taker beak path first traversed after seizure of the needle-thread loop by said beak. The guard-nger eX- tends laterally from its shank 15, adjustably secured upon a portion or" the bedplate 1 below the slide-plate 3, the securing means comprising a screw 16 passing through an elongated slot 17 ior ned in said shaft 15.

At the point of juncture of the guardnger 11i with its shank 15, the latter is formed with a notch 18 to provide clearance for the needle 6, the rearward wall 19 of said notch constituting an abutment for the loop of needle-thread seized by the looptaker. As the lower surface of the guard- 'inger is barely out 'of Contact with the looptaker rbeak and as the abutment wall 19 is opposed to the direction of movement of said loop-taker beak when seizing a loop of needle-thread, it is apparent that said wall 19 functions to cause the needle-thread loop to slide along the loop-taker beak yand to be rapidly spread by the inclined edge 20 of said beak. The projection 21 forming the forward wall of the notch 18 is part-ly cut away and' is beveled upwardly to guide the needle-thread loop as it is drawn up after being cast aboutY the bobbin-carrier.

ll-laving thus set forth the nature of this invention, what I claim herein is:

1. ln a sewing machine, a cloth-plate, a reciprocatory needle, a vertical-axis looptaker below said cloth-plate having a loopseizing beak traversing a horizontal path to cast needle-thread loops about a lowerthreadV mass, and a stationary guard-member disposed between the loop-taker and the cloth-plate overlying that portion of the loop-taker beakl path first traversed by said beak after-engagement of the needle-thread loop Ito thereby prevent sagging of the thread-chaininto said loop-taker beak path.

2. ln a sewing machine, a cloth-plate, a reciprocatory needle. a vertical-axis looptaker below said cloth-plate having a loopseizing beak traversing a horizontal path to cast needle-thread loops about a lowerthread mass, anda lined segmental guard finger lisposed between the loop-taker and the cloth-plate, said guard-finger overlying aA portion ot the loop-taker bea-k path to prevent sagging of the thread-chain into said path.

3. In a sewing machine, a cloth-plate, a reciprocatory needle, a vertical-axis loop-taker below saidcloth-plate having a loop-seizing beak traversing a horizontal path of movenient to cast needle-thread loops about a lower-thread mass, and a iXed segmental guard-finger disposed between the looptaker and the cloth-plate to overlie a portion of the loop-taker beak path, said guardiinger being provided with a needle-thread loop abutment wall directly rearward of the needle.

al. ln a sewing machine, a cloth-plate, a reciproeatory needle, a vertical axis looptaker below said cloth-plate having a loopseizing beak traversing a horizontal path of movement to cast needle-thread loops about a lower-thread mass, and a iXed segmental guard-finger disposed between the loop-taker and the cloth-plate to overlie a portion of the loop-taker beak path, said guard-iinger being provided with a needleclearance notch, the rearward wall oi' said notch constituting a needle-thread loop abutment, and the portion of the guard-iinin frontof the notch being beveled upwa illy toward the Cloth-plate to guide the disiiarged needle-thread loop.

in testimony whereoil l have signed my naine to this specification.

VILLLXM NELSON PARKES.

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