US2425970A - Sewing machine - Google Patents

Description

Aug. 19, 1947. J. H. VAN. VORST SEWING MACHINE Filed April 1, 1944 anVzm ATTORNEYS INVENTOR Jamesiz. V

Patented Aug. 19, 1947 UNITED STATES ATENT OFFICE SEWING MACHINE Application April 1, 1944, Serial No. 529,083

Claims.

This invention relates to sewing machines, and more particularly to non-automatic means for restrainedly and deliberately moving the needle and needle bar of a machine to advanced or retracted positions after the machine has finished part of a stitching operation.

When stitching material by means of the usual sewing machine, it is common practice, often each time the machine is stopped upon completion of some stitching, to operate the needle and needle bar of the machine by grasping the hand wheel and turning same for the purpose of either lifting the needle out of the work, or embedding it deeply into the Work, depending on whether the latter is to be moved bodily to a new position, or merely turned for changing the direction of sewing.

In some instances machines have been provided with automatic stop mechanisms whereby the needle is always lifted entirely out of the work when the machine is brought to a standstill, but this is not always desirable, especially if the machine has to be stopped for abruptly changing the direction of stitching.

The advantage of manual control of the needle, as compared with automatic control, is that an operator is enabled to readily meet the various requirements of shifting and turning of the work when carrying out diversified sewing operations. However, when employing this method, before the operator can use two hands toraise the presser foot and manipulate the work for the next stitching operation as is often necessary, he must first use one hand on the handwheel to position the needle either in or out of the work. This is wasteful of time, and often inconvenient, as well as tending to tire the operator.

It is an object of the present invention to provide an improved needle control mechanism which obviates the above disadvantages by enabling an operator, without the use of his hands, to quickly and conveniently adjust the needle position after the machine has been stopped. Thus both hands of the operator are immediately available for raising the presser foot and manipulating the work to a new position, without lost time and tiresome extra movement.

This is accomplished by providing a novel foot or leg-operated mechanism having a normally disengaged connection with a, driving shaft of the machine whereby the normal running of same is not interfered with, yet, when the machine is at a standstill, the mechanism can be operated to restrainedly turn the shaft and position the needle as desired.

A feature of the invention is the provision of a needle adjusting mechanism as above described wherein, if the machine is inadvertently started during use of the mechanism, no damage will result to the operator, nor to any of the parts of the mechanism, and there will be no delay whatsoever in the sewing operations. Thus an operators speed or production is not hampered by having the mechanism On a machine.

Another feature of the invention is the provision of a mechanism as above wherein theparts are few and simple to manufacture and install on existing machines, and wherein they may be quickly and conveniently replaced.

Other features and advantages will hereinafter appear.

In the accompanying drawings:

Figure 1 is a front elevation of a sewing machine showing the present invention applied thereto.

Fig. 2 is, a section taken on the line 22 of Fig. 1.

Fig. 3 is a view similar to that of Fig. 2 except that it shows the auxiliary needle-operating mechanism in engaged or working position.

Fig. 4 is a fragmentary front elevation showing a modification of the present invention.

Fig. 5 is a fragmentary right side elevation of the modification of Fig. 4.

Fig. 6 is a face view of the cam for controlling the clutch of the modification of Fig. 4.

Fig. '7 is a face View of the follower disk for the cam of Fig. 6.

As shown in Figs. 1 and 2, the machine embodying the present invention comprises a bench top H) carried on legs H and supporting a machine worktable [2 having a vertical post [3, horizontal arm l4 and sewing head i 5. A needle I6 is carried by the head l5 for reciprocating movement in the usual manner, said needle being operated in response to turning of the main shaft 1 l of the machine. The usual looper mechanism (not shown) is located within the table l2 below the needle i6, and operated in connection with turning of the shaft 1 I to produce stitches in work fed past the needle [6. The shaft l1 carries a handwheel l8 and pulley Hi, the latter being driven by a belt 20 from a suitable source of power, such as a motor 2|.

The machine as operated for sewing may receive its motive power by means of the belt 20 and pulley l9, and when the machine is to be stopped after completing a group of stitches, thedriving force is removed from the belt 20, as by switching off the current to the motor 2!. When this is done, the needle l6 and operating mechanism therefor including the shaft I! will come to a standstill in any one of a large number of possible positions. This position may be such that the needle is more or less extended into the work, or it may be entirely retracted. Prior to the present invention, in order to position the needle in either retracted or extended position as desired, the operator had to. reach up, grasp the handwheel l8 and turn the necessary amount.

According to the present invention this time. and attention consuming operation is obviated by providing means for controllably moving or positionin'g the needle 16 of the machine after the.

latter has come to a standstill-which may'be-operl ated or controlled by some part. ofthe operators body or limbs other than his hands, for. instance, by his knee or leg. Thus the operator has' the free use of his hands to manipulate the presser bar and the work as maybe required, and in addition to the. saving in time,.the elimination. of the handwheel manipulation results in. a simplification of the motions required of an. operator, and.

therefore a reduction in fatigue.

In the form-of this invention illustrated herein, as exemplary thereof, the needle positioning mechanism isadapted to be operated in response to movement of the operators knee,.thus leaving the operators feet free to remain on any. other controls such as the motor control. which. they usually operate.

The mechanism for acomplishing this,.as shown in Figs. 1, 2 and 3 comprises a disk 22 rigidly fastened to the shaft l1 and having buttress. teeth 23 around its periphery, the teeth being positioned so that duringforward rotation of the shaftthe sloping face of each tooth leadsthe driving faces thereof.

For the purpose of engaging and. driving. the

disk 22, a vertically positioned rack 24 having a.

lateral extension 25 at its lower end is pivotally and slidably mounted in a vertical guide 26- fastened to the post I3. The rack or driving member 24' has buttressteethll along one edge which are positioned and adapted to engage the teeth 23 of the disk to drive. the latter, the driving. face of each of the teeth 21 being. on the underside thereof, and the sloping faceonthe upper side.

The extension 25 of the rack is apertured near. its center to receive a pivot screw 28 about which the rack may swing,.said screw being carried by a. roller- 29 which is movable ina vertical groove 30 of T-cross section, in the guide 26 The. upper end. of the grove 30 is provided with a closure 3.! functioning as a stop for the roller 29,. and a-helical' compressionv spring 32 islocated in said groove to engage the roller 29 and yieldably hold same against the closure! ,the lower endof t-hespring 32 bein anchored against a closure 33- at the lower end of the groove. The diameter of the coils of the spring 32 is suficiently great to cause it tobe confined in the groove and prevent its buckling and extending out of the narrow throat thereof.

As thus mounted, see Fig. 2, the rack 24 may be pivotally moved so that the teeth- 21' thereof will engage the teeth 23 of the disk for driving the latter, and this driving may be accomplished by bodily moving the rack 24 downwardly, while its teeth are engaged, against the yielding pressure supplied by the spring 32. When thisis done, the shaft I? will be caused to rotate in. a clockwise direction as indicated by the arrow in Fig; 3.

For the purpose of operating the rack 24, a link 34- is provided, extending through; an aperture 4 35 in the bench ID, the upper end of the link being pivotally connected to the rack at the end of the extension 25 thereof, the latter being apertured and having a pivot screw 36 to provide this connection. The link 34 passes through a laterally extending apertured lug 3'! at the lower end of the guide 26 and under the bench ID, the lower end of. the link is pivotally connectedto an operable member 38' whichis in turn pivotally carried by a bracket 39 fastened to a horizontal brace 40 across the legs I l. The member 38 has a depending extension 4| adapted to be engaged by the thigh or knee of an operator, so that pressure thereon will cause the member to pivot and turn in a. counterclockwise direction; (see Fig. 1) and cause the link 34- to be moved downwardly.

In order to provide for return movement of the operable member 38 and link 34, and also to yieldably hold the rack 24 out of engagement with the disk ..2 a helical compression spring 42 i carried on. the link so that. its. ends. respectively engage and press. against the. lug 31. of theguide. and. a collar &3 adjustably mounted on the link adjacent. the pivot 36. The, pressure of the spring 42. may be adjusted to. the. desired value. by shifting and. locking the collar 43' on the link 34,.a set screw being. provided in thecollar. for this purpose. The link. 35 also carries a collar 43!). held by a set screw and locatedto engage. the underside. ofthe lug 3'! of the slide to functionas. a stop when the.

rack.24 is in the disengaged position of Fig. 2.

Another means which functions to disengage.

the. rack 24 from. the disk 22 upon release of. the

operable member 38 is shown, in. the. form of a,

clockwise direction,.looking at Fig. 2,,as the spring 32. continues. to expand, thus separating the. rack fromthe disk 22.

Th rack 29 and gear 22. ofthe improved needle positioning means as above set, forthfunction. in the manner of. a clutch. During normal operation of. the machine for sewing, the rack 24 is yieldably heldin the disengaged position of Fig, 2 by the spring. 42, and the machine runs entirely free from any influence of the positioningmeans. Whenthe machine is brought, to a standstill and it is desired. to project or withdraw th needle, I6, the operator merely presses with his. leg. against", theextension ii of the operable member, as shown by the arrow inFig- 1.. This moves the link 34. downwardly,.causes therack 24' first to pivot so as to engage the teeth 2.? thereof with the teeth 23 of the disk 22 and then to-bodily move downward- 1y against the pressure of the springs 32 and. 42. so as-to slowly and. controllably driv the disk 22 in: a clockwise direction, as in Fig. 3. This turns the shaft H forwardly, and by this method the needle is may be adjusted or positioned either up or down, the final position of the needle deending upon the point at which the needle stopped and the amount of movement imparted to the mechanism by the operationv of the lever 4| necessary to continue the drive until the desired position is reached.

For instance, when the machine stopped the needle may have just left the work and the operator may desire to have the needle penetrate and impale the work. In this case, the lever 4| would be operated to cause the needle to continue to rise and then descend until it entered and held the work. With the device of this invention, because of the leverage between the lever 4| and the shaft H, the latter may be moved smoothly and under complete control to bring th needle to desired position.

The movement of the lever 44 need not be accomplished with any special caution or care for if the desired position of the needle is overshot the lever 4| may be again operated to reach it. An experienced operator observing the position of the needle quickly learns the amount of movement to give the lever, and whether the movement should be accomplished by a light blow or tap or by follow-up pressure. When the operator removes the pressur against the extension 4!, the action of the springs 32 and 42 will return all the parts to the position of Fig. 2, in readiness for sewing to be resumed.

By providing teeth on the disk 22 and rack 24 in buttress form, the clutch comprising these parts is adapted for one way drive only, and during the return of the rack to its disengaged position of Fig, 2, the teeth may slide or ratchet past each other but cannot prevent such return from taking place.

Moreover, if the machine should be started up prematurely, before the rack has become disengaged from the disk, the teeth will merely slide past each other and no harm will be done, nor will any delay in the sewing be occasioned by this occurrence.

In Figs. 4 and 5 there is shown another form of the invention. There the clutch means comprises a pair of disks adapted to engage each other for unidirectional driving. As shown, the main shaft I'Ia of a sewing machine, carrying a handwheel 18a and a drive pulley Isa, has fastened at its end a clutch disk 2211 having around its P riphery and extending laterally or axially thereof buttress teeth 23a. A driving disk 24a is carried on a spindle 44 axially aligned with the shaft Ila and journaled in a bracket 45 fastened to the post ISa of the machine, the disk 2411 having buttress teeth 21a for engaging the teeth 23a of the disk 22a to drive the latter and the shaft I la forward- 1y. The spindle 44 is movable axially as well as rotatable in its journal in the bracket 45, and therefore, the driving disk 24a may be moved axially to engage or disengage the driven disk 22a.

In order to control the axial movement of the driving disk 24a the bracket 45 is provided with a circular cam 45, Figs. 4 and 6, having a pair of quadrant-shaped faces 41 and 48 located on opposite sides of the spindle 44, the portion 49 between the faces being recessed, and the radial edges of the faces being sloped as at 50 (see Fig. 4). Cooperating with the cam 46 is a disk 5 l Figs. 4 and '7, fastened on the spindle 44 and having a pair of lugs 52 with sloped radial edges, the lugs being thus adapted, when the spindle 44 is turned, to ride up out of the recessed portions 49 of the cam onto the faces 41 and 48 thereof, and in so doing to disengage the disks 24a and 22a. A helical compression spring 53, carried in a circular groove in the inner face of the bracket 45 to bear against the driving disk 24a, provides a constant pressure tending to move the disk 24a into engagement with the disk 22a for driving. As thus arranged, referring to Fig. 4, the disk 24a is normally disengaged from the disk 22a during operation of the machine for sewing, but if the spindle 44 is turned slightly in a clockwise direction as indicated by the arrow in Fig. 5 to move the lugs 52 past the cam faces 41 and 48, the sprin 53 will move the assembled driving disk 24a, spindle 44 and disk 5| axially as permitted by the lugs 52 entering the recesses between the cam faces 41 and 48 and the driving disk 2411 will engage the disk 22a. Further clockwise turning of the spindle 44 will cause the disk 24a to drive the disk 22a and shaft I la forwardly, so that the needle of the machine may be positioned where desired.

For the purpose of operating the assembly of driving disk 24a, spindle 44 and disk 5| to position the needle, the disk 24a is provided with a radially extending arm 54, see Fig. 5, which is apertured at its end to pivotally connect with a link 34a extending downwardly through an apertured lateral extension a of the bracket 45 to a point under the machine table. The link 34a may be actuated by an operators lower extremity in the manner shown in Figs. 1 and 2, or by any other suitable foot or leg operated member.

. In order to yieldably hold the disks 22a and 24a in disengaged position, a compression spring 42a is carried by the link 34a, one end pressin against the extension 4511 of the bracket, and the other end pressing against a collar 43a fixed on the link by means of a set screw. A collar is fastened 0n the link 34a to engage the underside of the bracket extension 45a and act as a stop, the collar positioning the spindle 44 and disk 51 in the rotative position of Fig. 4 wherein the toothed disks are disengaged. The spring 42a also serves to return the various parts to their initial positions after the mechanism has been operated to adjust the needle.

As in the form of the invention shown in Figs. 1 through 3, if the machine is prematurely started while the disks 24a and 22a are still engaged, no damage will occur, but the teeth of the disks will merely slide past each other as in a ratchet due to the yielding pressure of the spring 53 and there will thus be no delay in the sewing operations. Normally, the disks 24a and 22a function as a clutch which is disengaged during sewing operation of the machine.

The term tardigradely is used herein to mean moving or steppin slowly, or slow pacing.

Variations and modifications may be made within the scope of this invention and portions of the improvements may be used without others.

I claim:

1. A needle advancing and retracting device for a sewing machine having a clutch adapted to be connected with the needle-driving mechanism of the machine to adjustably operate same, said clutch having means yieldably holding it in disengaged position; a member mounted for engagement by the lower limb of the operator and movable in response to pressure thereon by the operator; and means connectin said member to said clutch for causing engagement of, and for driving the clutch in response to movement of the operable member whereby the needle driving mechanism of the machine is adjustably operated to advance or retract the needle, the reverse movement of the operable member causing the clutch to disengage in response to said yieldable means and free the needle-driving mechanism for sewing.

2. The invention as defined in claim 1, in which the clutch is adapted for driving in one direction only whereby the needle-drive mechanism of the machine is adjustably operated only by uni-directional movement of the operable member, and whereby said mechanism may be operated for sewing in its forward direction without first disengaging the clutch.

3. The invention as defined in claim 1 in which the clutch comprises a driving member and a driven member, each having co-functioning buttress teeth gripping only for uni-directional relative movement whereby the needle-drive mechanism of the machine is ad-justably operated only by uni-directional movement of the operable member, and whereby said mechanism may be operated for sewing in it forward direction without first disengaging the clutch.

4. The invention as defined in claim 1 in which the clutch comprises a wheel fastened to the needle driving mechanism and having buttress teeth around its periphery, and a movably mounted; rack having buttress teeth adapted to engage the teeth of the, wheel for uni-directional drivingthereof whereby the needle-driving mechanism is adjust-ably operated only by uni-directional movement of the operable member, and whereby said mechanism may be operated, for sewing in its forward direction without first disengaging the rack from the wheel.

5-., The invention as defined in claim, 1; in which the clutch for operating the needle-driving mechanism comprises a pair of wheels having a, common axis, each wheel having buttress teeth adapted, to engage the teeth of the other for uni-directional relative driving, andone of said wheels being axially movable for engaging and disengaging the other in response to movement of the operable member whereby the needledriving mechanism is adjustably operated by" uni-directional movement, of the. operable membox, and whereby said mechanism may be operated for sewing in its forward direction without first. disengaging the said wheels.

6. Theinvention asdefined in claim 1 in which the. clutch for operating the needle-driving mechanism comprises a drivin and a driven wheel, each having a common axis and having buttress teeth adapted to engage the teeth of the other for uni-directional relative driving, and one of said wheels being axially movable for engaging and disengaging the other, in which there is a camfor controlling the engagement of the axially movable wheel, and in which the. operable. member is connected to operate said cam and the driving wheel whereby the needle-driving mechanism is adjustably operated by unidirectional movement of said operable member, and whereby.- said mechanism may be operated for sewing in itsv forward direction without first disengaging the said. wheels.

7'. The invention as defined in claim 1 in which the-clutch for operating the needle-driving mechanism comprises a dlivingand a driven Wheel, each having a common axis and having buttress teeth adapted to engage the teeth of the other for uni directionalrelative, driving, and one of said: wheels being axially movable for engagingand disengaging; the other, in which there are yieldable means for moving the axially movable wheel to engage the other, and in which the operable member is connected to control said yield able means andto operate the driving wheel whereby the needle-drivingmechanism is adjustably operated by uni-directional movement of' said operable member, and whereby said mechanism; may be operated for sewin in its; forward direction without first reversibly moving the said operable member to disengage the said wheels.

8.. In a sewing machine a needle advancing and retracting device, including a clutch having'a driven disk connectedto-turn with the'main shaft of the machine and a driving disk mountedinaxial alignment withthe driven, disk, each of said, disks having buttress teeth adapted to engage the teeth of the other for uni-directional relative driving, and the driving disk being axially movable to engage and disengage the driven disk; means for yieldably holding the driving disk in engagement with the driven disk; a cam and follower connected with the driving disk for axially moving and holding same out of engagement with the driven disk; an operable member shaped for engagement with an, operators lower extremity; means for movably mountingthe operable member on the machine frame; andmeans for connecting the operable member with the driving disk and cam whereby unidirectional movement of saidmember will oper ate the cam to'release the disk to engaging position, andwill turn the disk to operate the shaft of the machine and advance or retract the needle.

9. In a sewing machine, a needle advancing andretracting device having a clutch disk connected to turn with the main shaft of the machine, saiddisk having buttress. teeth around its periphery; a rack having buttress teeth adapted to engage the teeth of the disk for uni-directional driving of the latter to turn the machine. shaft forwardly; meansv for mounting the rack, on the machine frame for lateral movement to and from an engaging position with the disk, and for advancing longitudinal movement when engagedwith the disk in a direction to drive the latter; means for yieldably holding the rack in retracted position and out of engagement with: the disk; an operable member shaped for engagement by an operators lower extremity; means for mounting the operable member on the machine. for movement in response to pressure from the operator; and means, responsive to movement ofthe operable, member for operating the rack whereby the latter iscaused to engage. and to drive the clutch disk to operate the machine shaft for advancing or retracting the needle, and whereby upon release of the operable member same will have its movement reversed and the rack will be: disengaged from the disk: by said yieldable means.

10. In a sewing machine having a main shaft, a. needle advancing and retracting device having a. clutch disk fixedly carriedv by the. main shaft of the machine to rotatably movesame-f-orwardly for positioning the needle, said disk having but tress teeth around its periphery which are positioned so that during forward rotation of the shaft the sloping faces of' the teeth lead the driving faces thereof; a driver having a plurality of buttress teeth adaptedv to engage the teethiof' the disk for driving same andthemachine shaft forwardly; means for movably mounting the driver on'the machine for both rotationaland translational movement whereby the teeth thereof may engage and disengage the teeth of the'disk' and whereby said driver may be moved, While its teeth are in engagement, in a manner to drive the disk; means, including a spiral spring, for yieldably maintaining the driver in a retracted non-driving position where the teeth thereof are disengaged, from those of the disk; an operablemember shaped for engagementwith an operators lower extremity; means for mounting the operable member on the machine frame for reversible movements; and means responsive to movement of the operable member in one direction by the machine operator for operating the driver against, the opposition of the spiral spring whereby the: teethof the diskare engaged by those of the driver, and the latter is moved to drive the disk and main shaft for positioning the needle of the machine, and whereby, upon release of the operable member, the driver and said member will be returned to their initial positions by the means for yieldably maintaining the driver in retracted position.

11. The invention as defined in claim 8 in which the cam and follower comprise a pair of quadrant-shaped surfaces connected to the machine frame and located on opposite sides of the axis of the driving disk and a pair of lugs attached to the driving disk for engaging said surfaces, said lugs and surfaces having camming edges adapted to engage each other whereby movement of the lugs with respect to the quadrant surfaces controls the axial movement of the driving disk.

12. In a sewing machine, a needle advancing and retracting device having a clutch disk connected to turn with the main shaft of the machine, said disk having buttress teeth around its periphery; a rack having buttress teeth adapted to engage the teeth of th disk for uni-directional driving of the latter to turn the machine shaft forwardly; means for mounting the rack on the machine frame for lateral movement to and from an engaging position with the disk, and for advancing longitudinal movement when engaged with the disk in a direction to drive the latter including a slide fastened to said frame and a pivot carrying said rack and movable in said slide; means for yieldably holding the rack in retracted position and out of engagement with the disk including a spiral spring pressing against the pivot, and another spiral spring providing pressure on the rack at a point removed from said pivot; an operable member shaped for engagement by an operators lower extremity; means for mounting the operable member on the machine for movement in response to pressure from the operator; and means responsive to movement of the operable member for operating the rack whereby the latter is caused to engage and to drive the clutch disk to operate the machine shaft for advancing or retracting the needle, and whereby upon release of the operable member same will have its movement reversed and the rack will be disengaged from the disk by said yieldable means.

13. In a sewing machine including a frame, stitching mechanism including a needle bar mounted at one end of the frame; a shaft for operating said needle bar; a driving mechanism for said shaft located adjacent the other end of the frame and employed when operating the machine for sewing; and auxiliary means separate from the driving mechanism and located at the end of the frame remote from said needle bar and having a drive member operated by a lower limb of the operator while the hands of the latter are free to engage the work, for inching the stitching mchanism to move the needle to a de sired position relative to the work, said auxiliary means also having spring means for normally urging the drive member into inoperative position.

14. In a sewing machine having a work supporting table, stitching mechanism including a needle bar; a driving mechanism including a drive shaft for th needle bar employed when operating the machine for sewing; and auxiliary means separate from the driving mechanism for rotating said shaft including shaft-actuating ratchet means carried by the shaft, an actuator therefor disposed below the table, a driving connector extending from the actuator to the means on the shaft, and resilient means for normally urging the ratchet means to inoperative position, said actuator being operated by a lower limb of the operator while the hands of the latter are free to engage the work for rotating the shaft and inching the stitching mechanism to move the needle to a desired position relative to the work.

15. In a sewing machine having a work supporting table, a frame; stitching mechanism including a needle bar mounted on one end of the frame; a shaft for operating the stitching mechanism; a driving mechanism for the shaft mounted adjacent the other end of the frame and employed when operating the machine for sewing; and auxiliary means at the latter end of the frame and separate from the driving mechanism for rotating said shaft including means carried by the shaft, an actuator therefor disposed below the table, a driving connector extending from the actuator to the means on the shaft, and resilient means normally urging the driving connection into inoperative position, said actuator being operated by a lower limb of the operator while the hands of the latter are free to engage the work for rotating the shaft and inching the stitching mechanism to move the needle to a desired position relative to the work.

JAMES H. VAN VORST.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,158,313 Seymour Oct. 26, 1915 1,484,217 Hemleb Feb. 19, 1924 1,721,070 Chason July 16, 1929 159,124 Tomlinson et al. Jan. 26, 1875 1,508,412 Robertson Sept. 16, 1924 FOREIGN PATENTS Number Country Date 11,002 Great Britain July 29, 1915 with (9077

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