US2718861A

US2718861A - Sewing machine

Info

Publication number: US2718861A
Application number: US241762A
Authority: US
Inventors: Samuels Arnold Jay
Original assignee: Individual
Current assignee: Individual
Priority date: 1951-08-14
Filing date: 1951-08-14
Publication date: 1955-09-27
Anticipated expiration: 1972-09-27

Description

Sept. 27, 1955 A. J. SAMUELS SEWING MACHINE Filed Aug. 14, 1951 INVENTOR flE/VOLD Jfl) M0545, BY"; 7

ATTOR NEYS United States Patent Ofiice SEWING MACHINE Arnold Jay Samuels, Forest Hills, N. Y.

Application August 14, 1951, Serial No. 241,762

Claims. (Cl. 112-220) Whereas conventional sewing machines employ feeding mechanisms for advancing the work relative to the needle, the present invention relates to sewing machines wherein the movement of the work controls the movement of the needle.

For a number of uses, the sewing machine contemplated herein willbe highly preferable to conventional machines for a number of reasons. The present invention relates to a very simple mechanism lending itself to lightweight construction and ready portability. It avoids the undesired superimposition of stitches under circumstances where the work is not being properly fed. It avoids the danger of needle breakage so commonly encountered with standard machines when the feed is improperly timed relative, to the needle.

The sewing machine of the present invention comprises a frame defining a work feed path, an intermittent motor carried by the frame, a needle bar carried by the frame and connected with the. motor, a work engaging member carried by the frame in the work feed path, and motor energizing means actuated by the work engaging member intermittently energizing the motor and needle bar at a rate proportional to the work feed. The intermittent motor is preferably a reciprocatory electromagnetic motor included in a circuit containing a switch actuated by the work engaging member for intermittently energizing the motor. The work engaging member is preferably a roller which in turn actuates a cam serving as a rotary switching member to energize and deenergize the motor for driving the needle bar and bobbin means carried by the frame. The armature of the electromagnetic motor is preferably biased in a direction to retract the needle from the work by means of a spring so that energization of the motor moves the armature. in opposition to the spring. Energization of the motor is followed by deenergization thereof through the agency of additional switching means so that the needle and bobbin movements will be intermittent and at a rate proportional to the work feed. The bobbin movement will be properly synchronized with the needle bar movement under all conditions to assure the effectiveness of the stitches.

A more complete understanding of the invention will follow from a detailed description of the accompanying drawings wherein:

Fig. 1 is a somewhat diagrammatic sectional elevation of the machine;

Fig. 2 is an elevation partially in section taken along line 22 of Fig. 1 and partially broken away;

Fig. 3 is a fragmentary section of a detail taken along line 33 of Fig. 1; and

1 Fig. 4 is a section taken along line 4-4 of Fig. 1.

The'frame of the machine may be defined by standard angles-10 supporting a bed plate 12 removably secured thereto, an upper front cover plate 14, a lower front cover plate 16, a bottom cover plate 18, a rear cover plate 20, a top cover plate 22, end cover plates 24, a

lead 122 and the power source.

Patented Sept. 27, 1955 mounting plate 26, and a closure plate 28 serving as a vertical partition defining the throat.

The needle bar 30 projects through the mounting plate 26 providing a socket for a needle 32 which penetrates an opening 34 in the bed plate or throat plate for cooperation with a rotary bobbin 36 which may in fact be a bobbin or shuttle of any type consistent with operation of the machine. A presser foot 38 is movable in the ordinary manner as indicated by the arrow 40 inscribed on the presser bar 42. The lower end of the presser bar 42 is enlarged and hollow to receive a pressure roller 44 rotatably mounted therein about a shaft 46 so as to bear upon the work 48, shown in Fig. 2, and assure contact between the work and a work engaging roller 50 carried by a shaft 52 which is hung in bearings 54 secured to the underside of the bed plate 12. i

The end of the shaft 52 remote from the roller 50 carries a gear 56 which meshes with a smaller gear 57 secured to a shaft 58 on which a cam 59 is adjustably and replaceably mounted by means of a nut 60.

The needle bar 30 is reciprocably mounted in a guide 61 suitably secured to the mounting plate 26, the upper end of the needle bar being secured by means of a screw 62 to a cross arm 64 whose opposite end adjustably rec'eives the threaded end 66 of a rack bar 68 secured in a desired position by means of 'nuts 70. At an intermediate portion of the cross arm 64, there is secured an armature 72 by means of a machine screw 74, the armature and its cross arm being downwardly movable under the influence of an electromagnetic winding 76 which, when energized, overcomes the elevating force of a biasing spring 78 interposed between the upper end of the magnet winding and the cross arm. The stator or winding 76 of the electromagnetic motor is suitably secured to the mounting plate 26.

A guide 80 for the rack bar 68 is likewise suitably secured to the mounting plate 26, and the lower end of the rack bar 68 carries a toothed rack 82 for driving a pinion 84 whose shaft 86 is mounted on the frame by means of a bracket 88. The pinion 84 meshes with a smaller gear 90 secured to the shaft 92 which is coaxial with the bobbin shaft 94. The shaft 92 is journaled in suitable bearings 96, and carries a member 98 of a one-way clutch 100 whose other member 102 is secured against rotation on the shaft '94 to impart rotary movement to the bobbin 36. The shaft 94 is likewise suitably journaled in bearings 104 mounted on the lower closure plate 18 of the frame.

Energization of the winding 76 of the electromagnet is effected when the work 48 causes rotation of the roller 50 carried by the shaft 52 on which the gear 56 is mounted. As the cam 59 is rotated by the

gears

56 and 57, it separates switch arms or

operators

106 and 107 carrying contacts 108 and 110 respectively. These contacts are separated at a frequency dependent upon the rate of rotation of the shaft 52 and the number of lobes on the cam, which of course can be varied by the mere substitution of cams having more or fewer lobes. The contact 108 is connected by a lead 112 through a junction 113 with a lead 114 extending to a switch arm 115 of a relay 116, the arm 115 carrying a contact 117 which normally engages a contact 118 carried by a switch arm 119 having a lead 120 connecting with one terminal of the electromagnet winding 76. The other terminal of the winding is connected through a lead 122 with a power plug 124. The other side of the power plug is connected by means of a lead 126 with the switch arm 107. A lead 128 also connected with the junction 113 is connected with one terminal of a winding 130 of the relay 116, the other terminal being connected by a lead 132 to the The switch arm 115 3 carries a projection 134 extending into the path of an actuator 1'36 carried by the rack bar 68 so that when the rack bar reaches a predetermined position, the

contacts

117 and 118 will be separated.

With the'various elements in the positions depicted in Fig. 1, when the power plug 124' is inserted in a socket,

current will flow from the plug 124' through lead 126,

switch arm 107, contact 110, contact 108, switch arrn 106, junction 113, switch arm 115, contact 117, contact 118, switch arm 119, lead 120, the winding 76 of the electromagnetic intermittent motor, lead 122, and back to the power plug and source. At the same time, current will flow from the junction 1 13, through lead 128, relay winding 130 and lead 132 back to source, but the relay is so designed that energization of the winding 130 is, insuflicient to open the

contacts

117 and 118. However, once the switch arm 115 is lowered, the energized winding. 130v will maintain the contacts separated. When the circuits are thus completed, the electromagnet winding 76 will be energized and move the armature 72 downwardly against the force of the biasing spring 78 to project the needle 32 through the work and at the proper instant, previously predetermined and adjusted by means of the nuts 70, the rack bar 68 carrying the rack teeth 82 will rotate the pinion 84 and at an increased speed, the gear 90 to produce the looping action of the bobbin 36. At a predetermined portion of the stroke, the actuator 136 engages the projection 134 to break the

contacts

117 and 118. This breaks the circuit of the winding 76 causing the spring 78 to elevate the armature 72. As the cam continues to rotate, the contacts 108 and 110 will be separated and the winding 130 of the relay 116 deenergized, permitting its

contacts

117 and 118 to close for the initiation of a new cycle. As the needle is retracted from the work, it will draw the stitch tight through the use of suitable tensioning means not shown, but well known in the art, and as the rack bar 68 is withdrawn, it will rotate the

gears

84 and 90 without reversely rotating the bobbin shaft 94, thanks to the one-way clutch 100.

It is contemplated that the presser bar 42 along with its presser foot 38 and pressure roller 44- be elevated by suitable means also well known in the art and therefore not shown, prior to the introduction of the work to be sewed.

There are many variations and refinements of this invention in contemplation, a number of which will occur to those skilled in the art after reviewing the present disclosure of a typical embodiment. Accordingly, it is not intended that the invention be restricted to this single illustration beyond the scope of the appended claims.

I claim:

1. A sewing machine comprising a frame defining a work feed path, an intermittent motor having a circuit carried by said frame, a needle bar and hook means carried by said frame and connected with said motor, a work engaging roller member carried by said frame in said work feed path, transmission means connected with said roller and a switching member in said circuit connected with said transmission means. and actuated bysaid work engaging roller member intermittently energizing said motor at a rate. proportional to the work feed.

2. A sewing machine comprising a frame defining a work feed path, an intermittent electromagnetic motor carried by said frame, a needle bar and hook means carried by said frame and connected with said motor, a work engaging roller member carried by said frame in said work feed. path, a circuit including said motor and a switch actuated by said work engaging roller member for intermittently energizing said motor at a rate proportional to the workfeed, and transmission means interconnecting said roller member and switch.

3. A sewing machine comprising a frame defining a work feed path, a reciprocatory electromagnetic motor carried by said. frame, a. needle bar and hook means carried by said frame and connected with said motor, a work engaging friction roller carried by said frame in said work feed path, a cam driven by said roller, a switch in circuit with said motor, said switch including an operator in the path of said cam whereby said switch is actuated by said cam intermittently energizing said motor at a rate proportional to the work feed.

4. A sewing machine comprising a frame defining a work feed path, an intermittent electromagnetic motor having an armature carried by said frame, a needle bar and hook means carried by said; frame and connected with said armature, a spring biasing said armature in one direction, a work engaging roller carried by said frame in said work feedv path, transmission means connected with said roller, and motor switching means connected with said transmission means and actuated by said work engaging member intermittently actuating said armature in opposition to said spring at a rate proportional to the work feed.

5. A sewing machine comprising a frame defining a work feed path, an electromagnetic motor carried by said frame, a needle bar and hook means carried by said frame and connected with said motor, a work engaging roller carried by said frame in said work feed path, transmission means connected with said roller, and a plurality of switches at least one of which is connected with said transmission means and actuated by said work engaging member intermittently energizing and deenergizing said motor at a rate proportional to the work feed.

6. A sewing machine comprising a frame defining a work feed path, intermittent motor means carried by said frame, a needle bar and hook means carried by. said frame and connected with said motor means, a work engaging roller member carried by said frame in saidwork feed path, switching means for said motor means, transmission means driven independently of said motor interconnecting said roller member and switchingmeans and actuated by said work engaging roller member to operate said switching means and energize said motor intermittently at a rate proportional to the work feed.

7. A sewing machine comprising a frame defining a work feed path, an intermittent reciprocatory motor carried by said frame, a needle bar and hook means carried by said frame and connected with said motor, a work engaging roller member carried by said frame in said work feed path, motor energizing means carried by said frame, transmission means driven independently of said motor interconnecting said roller member and motor energizing means actuated by said work engaging roller member to energize said motor intermittently at a rate proportional to the work feed.

8. A sewing machine comprising a frame defining a work feed path, an intermittent electromagnetic motor having a circuit carried by said frame, a needlebar and hook means carried by said frame and connected with said motor, a work engaging roller member carried by said frame in said work feed path, motorenergizing means.

carried by said frame, transmission means driven indepen-. dently of said motor interconnecting said roller and motor energizing'means, said motor energizing means including a switch connected, in said circuit actuated by said work engaging roller member to energizesaid motor intermittently at a rate proportional to the work feed.

9. A sewing machine comprising a frame defining a work feed path, an intermittent motor carried by said frame, a needle bar and hook means carried by said frame and connected with said motor, a work engaging. roller carried by said frame in said work feed path, motor energizing means carried by said frame, transmission means driven independently of said motor interconnecting said motor energizing means and roller, said motor energizingmeans. being actuatedby said roller to energize said motor intermittently at a rate proportional tov the workfeed.

10. A sewing machine comprising a frame defining a work feed path, an intermittent motor carried by said frame, a needle bar and hook means carried by said frame and connected with said motor, a work engaging roller member carried by said frame in said Work feed path, motor energizing means carried by said frame, transmission means driven independently of said motor interconnecting said energizing means and roller, said motor energizing means includingfi'a cam connected with said transmission means actuated by said work engaging roller member to operate said energizing means and energize said motor intermittently at a rate proportional to the work feed.

References Cited in the file of this patent UNITED STATES PATENTS