US1784724A - Sewing-machine feed - Google Patents

Description

Dec. 9, 1930. J, GARDE 1,784,724

SEWING MACHINE FEED Filed May 18, 1928 2 Sheets-Sheet l [NI/671L014 Jo/m Gare/e $1 QQMMQQ 1 W? J. GARDE SEWING MACHINE FEED Dec. 9, 1930.

- 2 Sheen-Sheet 2 Filed May 18, 1928 frn enio Job/7 'araq Patented Dec. 9, 1930 umreosrarss PATENT "oFFicr;

JOHN Gan-DE, or 'rononro, ONTARIO, CANADA snwine-ivmcnmn rnnn Application filed May 18,

V 10 the number of parts to the minimum and facilitating the adjustment of thefeed or regulating the stitch. a

A still further object is to simplify the meansfor retaining the shuttlecin a rotary holder. j 1

The principal features of the invention consist in the novel construction and arrangement of the feed dog and its operating parts whereby the feeddog is rigidly mounted on a carrier which is raised. and lowered by a rotating cam and coincidently oscillated by a separate loosely connected crank mechanism, and the carrier is held in place by a flexible swivel member. 7

A further important feature consists in the novelconstruction and arrangement of the adjustable crank mechanism for oscillating the carrier whereby the throw of the'carrier may be accurately adjusted.

A still further feature of importance consists in the novel structure of gate for holding theshuttle whereby the use of holding races is eliminated. V v

In the drawings, Figure 1 is a perspective Figure 5 is a vertical sectional detail of the cam and dog carrier and its support taken through the line 5-5 of Figure 4.

The feed mechanism of sewing machines is undoubtedly the source of the greatest trouview of the machine, the bed plate beingpartdog, shuttle holder and the supporting parts 1928. Serial no; 278,728.

ble in the operation of the machines and many 'mechanisms have been devised in an effort to minimize this condition but up to the present no feed has been commercially produced which will give the desired result. The mech- '55 anism herein described has been subjected to the most severe tests for a considerable period and it has continued to function with regularity and precision although tested in feeding "from-extremely thin fabrics such as line no crepe and voile materials directly to thicknesses up toone-eighth of an inch or more.

The main structure comprises a carrier 1 which is in the form of a metal plate of sub stantially rectangular form having a cam-" shaped opening 2 therein to receive the cam 3 whichis carried'onthe main'shaft 4:. The opening 2 is formed with an arc-shaped side 5 which connects at one end with a straight horizontal portion 6 and at the other end with a straight sloping portion'Z; The cam 3 is formed with a concentric portion 8 connected by tangential portions 9 with a concentric portion 10 of a radius greater than 8.

A flat spring plate 11 is rigidly secured in a recess 12 inthe top of the carrier 1 and a spring plate 13 is arranged below the plate 11 having a vertical portion 14 abutting the inner face of the carrier and a horizontal end 15 extending above and spaced from the straight horizontal portion 6 of the carrier and is adaptedtoengage the surface of the cam on the side opposite that engaged by the portion 6 of the carrier.

An adjusting screw 16 is threaded in the 85 top of the carrier andextends into engagement withthe end 15 and is adapted to adjust the said end15 up or down. The mem ber 15 forms the contact surface of the carrier engaging the cam so that by its adjustment the lift of thecarrier is regulated.

The toothed dogl. is secured to the top of thecarrier and is formed with a slot 18 through which the needle 19 operates.

The carrier 1 is provided with a vertical slot 20 at one side of the opening 2. A crank member 21 carried on the shaft-22 mounted in the bed structure 23 is provided with a pin 24: which extends into the slot 20 and the versely in relation to the cam but the slot allows the carrier to raise and lower though it is so located as to impart a slight tilting action to the carrier at certain periods.

The plate 11 to which the carrier is secured is supported on a spring arm 25 which is pivotally connected thereto by the pin 26 which also secures the plate 13, said armbeing pivotally connected by a screw 27 to the underside of the bed plate 28 The spring arm 25 serves to normally support the carrier in an upright position and being pivoted permits the carrier to move transversely.

Upon the rotation of the cam 3 the tangent surface 9 engaging the plate 15 lifts the carrier upwardly until it rides on the surface 10 n: and as the carrier rises the pin 24 of the crank 21 engages the bottom ofthe slot 20 thus causing the carrier to tilt from its normal upright-position against the action of the spring arm so that the teeth of the dog are moved into sloping contact with the goods. being sewn, then as the crank 21 oscillates the carrier is returned to its normal upright position by the spring arm 25 connected therewith so that the dog assumesa horizontal position and ismoved transversely by the engagement of thepin 24 with the side wall of the slot 20 to feed the: goods forward. when the crank 21 reaches the limit of its oscillation the cam lowers the carrier which is then moved in the reverse transverse direction by the crank pin.

7 This operation is a very positive action and the goods are effectively held to the pressure foot of the machine and owing to the tilting action of the dog any extra thickness of the goods such as seams or inserts will not cause the dog to slip.

A small spring 29 is arranged in the side of the carrier to form a cushion against'the side wall of the casing enclosing the mechanism,

which obviates any rattle in the operation of the device. I

The crank shaft 22 is provided with a pair of crank arms 30 in the form of split arms which are clamped to the shaft by screws 31 thus enabling very simple adjustment. The

outer ends of the crank arms are engaged by a pin 32 carrying the lever arm 33 wh1ch 1s provided with a fork '34 at the top to engage the operating cam. This cam operating structure is common so is not shown.

The lever arm is supported on the fulcrum pin 35 provided with a roller 36 operating in a-slotted disc 37 journalled in the frame of the machine. This disc is rotated by a suitable handle 38 (see Figure 1) to alter the angularity of the slot in the disc. The alteration of the angularity of the disc alters the movement of the lever arm and consequently alters the throw of the crank pin engaging nism is formed with a projection 39 at the forward end upon which is pivotally mounted a gate member 40 which swings into a vertical position to hold the bobbin in the holder 41 which is carried on the main shaft.

The gate 40 is held in its vertical position by a spring hook 42 secured to the underside of the bed plate and is released by the pressure of the finger.

It will be seen from this description that the device is extremely simple and that there are very few working parts to retain in' adjustment. Further, the cost of construction is materially reduced and there are no delicate parts to become broken or easily dislodged.

What I claim as my inventionis 1. A sewing machine feed, comprising, in

combination, a carrier having a cam-shaped opening, a rotatable cam dlsposed 1n said carrier opening to raise and lower said car-- rier vertically, a feed plate rigidly secured to the top of said carrier, a spring arm pivotally secured at one end at a fixed point and being pivotally connected to said plate at the other end, said spring arm normally supporting said carrier and plate an upright position, means for reciprocating said carrier horizontally coincident with the rotation of the cam and means for tilting said carrier and plate out of their normal uprightposition against the'action of said spring arm toward the end of their vertical stroke.

2. A sewing machine feed, comprising, in combination, a cam, a carrier flexiblysupported and engaging said cam and lifted-- vertically thereby, said carrier being oscillatable'with respect to said cam and having a rotatable cam, a carrier mounted on said cam and lifted thereby, said carrier having a vertical slot therein, a rock shaft having a crank on one end thereof, a crank pin engaging said vertical slot, crank arms split longitudinally and encircling said rockshaft, means for clamping said split crank armsjin adjusted positions on said rock shaft, a lever arm pivotally connected to the outer ends of said crank'arms and having a aw-shaped upper end, a roller fulcrum on said leverarm, a

slotted disc engaging said roller fulcrum, and

means for turning said slotted disc to'alter the angularity of the slot in relation to the lever arm.

JOHNGARDE. a

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