US2276900A - Take-up for sewing machines - Google Patents

Description

Mar h 7, 1 2- M. L. WATERMAN TAKE'UP FOR SEWING MACHINES I Filed Aug. 25, 1939 s Sheets-Sheet 1 GUM M3 March 17, 1942.- M; L. WAT ERMAN v TAKE-UP FOR SEWING MACHINES- Filed Aug. 25, 1939 3 Sheets-Sheet 2 March 17, 1942. WATERMAN TAKE-UP FOR sswzue MACHINES Filed Aug. 25, 1939 S Sheets-Sheet 5 Maw L.-watefmaw $2M Q Patented M... 17, 1942 FAKE-UP FOR SEWING MACHINES Max L. Waterman, Fail-field, Conn., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey Application August 25, 1939, Serial No. 291,839

Claims- This invention relates to thread take-ups for sewing machines and, more particularly, to needle-thread take-ups for machines of the'small, portable, electrically driven, family type.

Machines of this type are commonly constructed with a rectangular box-like bed housing the under thread and feeding mechanisms as well as a lower rotary main shaft and its driving motor. The machine also has an overhanging bracketarm carrying the reciprocatory needle, presser and take-up devices. Where considerations of cost dictate the use of an upper oscillatory shaft instead of a rotary shaft for actuating the needle-bar, the provision of a needle-thread take-up, suitable for cooperation with a lower rotating hook, becomes a problem.

According to the present improvement, the take-up mechanism is located mainly in the bracket-arm standard and is actuated from its own individual eccentric on the lower rotary main shaft.

A novel dynamic balancer is also built into the bracket-arm standard to reduce vibration.

In the accompanying drawings, Fig. 1 is a longitudinal vertical section through a small, portable, electrically driven sewing machine embody-,

ing the invention. Fig. 2 is a section on theline 22, Fig. 1. Fig. 3 is a front end elevation of the machine and Fig. 4 is a detail View of a portion of the take-up mechanism.

The machine is constructed with a hollow boxtype bed 1 having side and end walls cast integral with its top and closed at its bottom by the removable wooden bottom plate 2. Rising from the bed I is the standard 3 of the overhanging bracket-arm ll terminating in the head 5.

J ournaled in the bed I is the rotary main shaft 6 carrying the combined balance-wheel and beltpulley l which is driven as usual by the electric motor 8 housed within the bed I.

Disposed within the bed I and driven by gears 9 9 from the shaft I is the two-to-one vertical axis rotary hook 9 with its stationary bobbinthread-case it. Also disposed within the bed is a feed-mechanism including a feed-dog l l with suitable means for imparting thereto rising-andfalling and feed-and-return movements.

Cooperating with the rotary hook 9 is the endwise reciprocatory eye-pointed needle l2 which is mounted in the needle-bar l3 journaled for endwise movements in the bracket-arm head 5 and connected by the link M to the crank-arm [5 on the rock-shaft I6 journaled on pintles IS in the bracket-arm 4 and having at its rearward end a crank I! which is connected by the pitman ll to the needle-driving eccentric It on themain shaft 6.

The eyed needle-thread take-up arm I9 is fixed to the take-up rock-shaft 20' which is'mounted on pintles 2| in the bracket-arm 4 and has clamped thereto a transverse cylindrical pin 22 which extends downwardlyfrom the rock-shaft 2!]. This pin is engaged and actuated bythe slide-block 23 pivotally carried at the forked upper end of the lever 24 the lower end of which embraces the take-up eccentric 25 on the main shaft 6.

Between its ends the lever is formed with a slot 26 which rides on the fulcrum-block 21 pivoted on the cross-pin 28 fixed in the standard 3.

As a dynamic balancer there is provided between the eccentrics IB and 25 a third eccentric 29 which is embraced by the lower end of a balancer-lever 30 slotted at 3| to ride on the fulcrum block 32 pivoted on the pin 28. At is upper end 32 the lever 30 is suitably weighted. The eccentric 29 is timed approximately from .the eccentric 25, as shown in Fig. 2.

The upper end of the lever 24 moves in an elliptical path, as shown in the dash-dot line, Fig. 2. One side of this elliptical path passes closer to the axis of the take-up rock-shaft 20 than the other side, while the ends of the elliptical path are about equidistant from the rockshaft 20. The result is that the take-up I9 is given a fast up-stroke and a slow down-stroke,

the former to take up the needle-thread-loop cast about the thread-case [0 by the rotary hook 9 and set the stitch and the latter to give thread to the needle 12 as its eye doubles the thread through the work and to the hook as it takes the thread-loop from the needle and expands the same for passage about the thread-case I0.

There is thus provided in a portable, family type, rotary hook sewing machine having an upper needle-operating rock-shaft, a simple balanced take-up mechanism which is properly timed for cooperation with said rotary hook and needle.

Having thus set forth the nature of the invention, what I claim herein is:

1. A sewing machine having a frame including a bed and overhanging bracket-arm with upright and laterally overhanging portions, a main shaft in said bed, a needle and needle-operating rock-shaft carried by said bracket-arm, a looptaker in said bed cooperatively related to said needle, a needle-thread take-up arm, a take-up rock-shaft carrying said take-up arm and disposed Within the laterally overhanging portion a pair of oppositely timed eccentrics on said shaft under the upright portion of said bracketarm, a pair of levers each embracing at its lower end a respective one of said eccentrics, a fulcrum for each of said levers between the ends of the latter, a take-up shaft in said bracket-arm, a needle-thread take-up arm actuated by said take-up shaft, and an operative connection between one of said levers and said take-up shaft, the other lever functioning as a dynamic balancer,

3. In a sewing machine having a bed and overhanging bracket-arm carrying a reciprocatory needle and needle-operating rock-shaft and a main shaft in said bed, the improvement which consists in the provision in the bracket-arm of a rock-shaft carrying the needle-thread take-up and the provision on the main shaft of a takeup actuating eccentric with a lever having a fulcrum between its ends and actuated by said eccentric and slidably connected at its upper end to a crank-arm on said take-up rock-shaft to actuate the latter with a fast and slow motion.

4. In a sewing machine having a bed and bracket-arm, a rotary main shaft in said bed, an eccentric thereon, a lever embracing said eccentric and extending upwardly into said bracket-arm, a fulcrum for said lever permitting endwise and rocking movements thereof, a thread take-up arm, a rock-shaft in said bracket-arm to operate said take-up arm, and a crank-arm on said rock-shaft operatively connected to the upper end of said lever.

5. A sewing machine having a frame formed with a box-type bed and overhanging bracketarm, a reciprocatory needle and needle-operating rock-shaft in said bracket-arm, a main shaft in said bed, a two-to-one rotary hook in said bed complemental to said needle, a take-up and take-up operating rock-shaft in said bracketarm, a crank on said take-up operating rockshaft remote from said take-up, an eccentric on said main shaft, and a follower lever embracing said eccentric and having a sliding connection at its upper end with said crank, there being a fulcrum connection with the frame between the ends of said lever, whereby said take-up rockshaft receives a fast and slow motion.

MAX L. WATERMAN.

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