US3628479A

US3628479A - Loop taker support for sewing machines

Info

Publication number: US3628479A
Application number: US43062A
Authority: US
Inventors: Rudolf Schafer
Original assignee: Singer Co
Current assignee: SSMC Inc
Priority date: 1970-06-03
Filing date: 1970-06-03
Publication date: 1971-12-21
Anticipated expiration: 1988-12-21
Also published as: JPS5429934B1; DE2126836A1; GB1325782A; FR2095799A5

Abstract

A support for mounting a loop taker saddle in the bed of a sewing machine in which the saddle is formed along opposite sides with parallel channels which slidably embrace and span ways which are secured in the machine bed. The loop taker saddle may be clamped in selected position in the sewing machine bed by a securing screw which is arranged to deflect one of the ways.

Description

United States Patent Inventor Rudolf Schaier Karlsruhe, Germany Appl. No. 43,062

Filed June 3, 1970 Patented Dec. 21,1971

Assignee The Singer Company New York, N.Y.

LOOP TAKER SUPPORT FOR SEWING MACHINES 2 Claims, 3 Drawing Figs.

U.S.Cl 112/167, 112/184,112/218 R [56] References Cited UNITED STATES PATENTS 2,476,061 7/1949 Parry 112/184 3,310,013 3/1967 Smith 112/184 Primary Examiner-H. Hampton Hunter Atrorneys-Marshal1.l. Breen, Chester A. Williams, Jr. and

Robert E. Smith ABSTRACT: A support for mounting a loop taker saddle in the bed of a sewing machine in which the saddle is formed along opposite sides with parallel channels which slidably embrace and span ways which are secured in the machine bed. The loop taker saddle may be clamped in selected position in the sewing machine bed by a securing screw which is arranged to deflect one of the ways.

PATENTEUBEEZ] l9?! 3628;479

SHEET 1 [IF 2 INVENTOR. Rudolf Schafer wrmsss: 2 4%; Q ATTORNEY PATENTED DEEZI l97| SHEET 2 0F 2 INVENTOR. Rudolf Schufer /Q ATTORNEY WITNESS 725w)? H D M LOOP TAKER SUPPORT FOR SEWING MACHINES BACKGROUND OF THE INVENTIQN It is conventional in the sewing machine art, where a loop taker saddle is employed, to support the saddle on the sewing machine bed by fastening which pass through slotted openings in the saddle and attach to the sewing machine bed. Use has also been made of a bed shaft or loop taker drive shaft or of the bushings for such a bed shaft to located and support the loop taker saddle. It has been difficult using the prior art loop taker saddle-supporting means to provide for an accurate adjustment of the saddle position because the very tightening of the fastenings often effected slight shifts of the saddle position. Moreover, with the prior art arrangements it has been difficult to obtain a clamping action which would maintain the loop taker saddle in selected position despite the vibration incident to sewing machine operation. If the fastening screws or bolts of the prior arrangements were tightened sufficiently to prevent loosening due to vibration, the fastenings frequently scored or deformed the slotted openings therefor in the saddle thus making it difficult, if not impossible, to obtain further slight adjustments at a later time.

SUMMARY OF THE INVENTION It is an object of this invention to provide a loop taker saddle supporting arrangement for sewing machines in which very accurate adjustment of saddle position is obtainable and in which exceedingly positive clamping of the saddle in selected position may be obtained.

It is also an object of this invention to provide a loop taker saddle-supporting arrangement in which clamping of the saddle in one selected position does not deform or mutilate the clamping means so as to make further slight adjustments difficult.

The objects and advantages of this invention are attained by the provision of substantially parallel channels in the opposite sides of a loop taker saddle which channels slidably embrace ways secured to the sewing machine bed. Provision is made for deforming one or both of the ways causing the loop taker saddle to be clamped in selected position along the ways. Sufficiently large area of contact is provided between the ways and the loop taker saddle channels which embrace the ways as to prevent any localized mutilation of these parts which would prevent subsequent slight adjustments in saddle position.

With the above and additional objects and advantages in view as will hereinafter appear, this invention will now be described with reference to a preferred embodiment illustrated in the accompanying drawings in which:

FIG. it represents a vertical cross-sectional view of the bed portion of a sewing machine having applied thereto the support for mounting a loop taker saddle in accordance with this invention,

FIG. 2 represents an enlarged cross-sectional view taken substantially along line 22 of FIG. 1 showing the loop taker saddle and the saddle-supporting means of this invention, and

FIG. 3 is a bottom plan view of the sewing machine of FIG. 1.

Referring to FIGS. 1 and 3, a sewing machine is illustrated having a bed 11, a standard 12 rising from the bed and sustaining a bracket arm 13 which overhangs the bed. The sewing machine is adapted simultaneously to form two separate rows of stitches, and to do this it is provided in the sewing head with a needle bar 14 to which is secured a needle clamp 15 which accommodates a pair of laterally spaced needles 16. A throat plate 17 carried on the bed to support work fabrics against the thrust of the needles is formed with apertures 18 through which the needles reciprocate endwise in the formation of stitches.

Indicated generally at 20 are rotary loop takers for cooperating one with each of the needles 16 in the formation of stitches. Each loop taker is carried in a saddle indicated generally at 21 which is shiftably supported lengthwise of the bed and may be clamped in selected position thereon. When a different spacing between the separate lines of stitches is required, a different needle clamp 15 is substituted having the desired gauge or needle spacing, a different throat plate is substituted having the appropriately spaced needle apertures, and the loop taker saddles 21 must be shifted into a new spacing of the loop takers for cooperation with the changed needle gauge. As is conventional in this type of two needle sewing machine, regardless of the needle spacing, the needles will always be arranged equally on opposite sides of a fixed medial plane. When'needle gauge is changed, therefore, a shift of the loop taker position of the two loop takers will always be required an equal amount in opposite directions.

The two loop taker saddles may be identical in construction and identical in means of support, and therefore the same parts will be indicated by like reference characters in the drawings save that the parts of the righthand saddle in the drawings will be denoted by prime numbers.

As best shown in FIG. 2, each of the loop taker saddles 21 comprises a closed compartment 22 through which a pair of

vertical shafts

23 and 24 are joumaled. Meshing gears 25 and 26 on the

shafts

23 and 24 respectively, are arranged within the compartment 22 and the loop taker 20 is secured as by a setscrew 27 to one of the shafts 23 above the saddle while a sprocket wheel 28 is secured to the other shaft 24 beneath the saddle.

For shiftably supporting and for selectively securing each of the saddles 21 in any one of a range of positions longitudinally of the sewing machine bed in accordance with this invention, each of the saddles is formed with parallel guide channels 30, one channel along each side of the saddle. As shown in FIGS. 2 and 3, the sewing machine bed is formed with spaced depending

webs

31 and 32 at each side of the throat plate. The

webs

31 and 32 extend lengthwise of the bed and define supporting blocks between which the loop taker saddles may be arranged.

Secured by fastening screws 33 to the

webs

31 and 32 are elongate ways 34 each extending longitudinally of the sewing machine bed and substantially parallel to each other and to the work-supporting surface of the sewing machine bed as defined, for instance, by the throat plate 17. Each of the ways 34 is formed with a guide surface 35 which is complemental to the guide channels 30 formed in the loop taker saddles and preferably as shown in FIG. 2 has a blunt angular shape.

The distance between the

webs

31 and 32, and the dimensions of the ways 34 of the channels 30 in the loop taker saddles are chosen so as to provide a snug support for the loop taker saddles which nonetheless will accommodate a free-sliding movement of the saddles along the ways lengthwise of the sewing machine bed. At least one of each pair of the ways for each of the saddles is formed with a recess 36 on the side opposite the guide surface 35 and between fastening screws 33 so that the ways which are so recessed will have an unsupported central portion between the fastening screws. The web 31 is formed with a threaded opening which accommodates a crew 37 disposed to abut the way along the recess 36. A lock nut 38 is provided on the screw 37. By tightening the screw 37 the recessed way may be deflected so as to lock the hook saddle in a selected position along the ways. While each of the ways 34 may be formed with a recess 36 and provided with an adjusting screw 37, it has been found adequate to provide for deflection of only one of each set of the ways for each saddle in order to securely clamp the saddles in place on the bed.

As shown in FIGS. 1 and 3, a main drive shaft 40 is journaled in the bed beneath the standard 12 and provided with a pulley 41 by which the sewing machine. may be powered from any suitable motor, power transmitter, or the like. A suitable drive may be provided from the main drive shaft 40 to reciprocate the needles 16 and a timing belt 42 is illustrated in FIGS. 1 and 4 meshing with a sprocket 43 on the main drive shaft 40 for this purpose. The main shaft 40 may also have fast thereon

rotary actuators

44 and 45 for imparting movement to a work-feeding mechanism. As shown in FIG. 4, such a workfeeding mechanism may include a feed bar 46 of a drop feed mechanism in which the rotary actuator 44 takes the form of a feed eccentric for imparting feed advance and return movements by way of a feed advance rock shaft 47 journaled in the bed, and the rotary actuator 45 takes the form of a gear for imparting movement to a feed lift driving shaft 48 journaled in the bed. Any conventional work feeding mechanism, however, may be employed.

For driving the loop takers 20, the main shaft 40 extends into a gear compartment 50 in the bed wherein a bevel gear 51 is secured thereto. Meshing with the bevel gear 51 is a bevel gear 52 which is fast on a stud shaft 53 journaled vertically in the bed compartment 50. Beneath the gear 52 and below the compartment 50 a sprocket wheel 57 is carried on the stud shaft 53.

The driven

sprockets

28 and 28 for each of the loop takers are driven synchronously from the drive sprocket 57 by a single timing belt 70. The timing belt 70 is directed to the driven

sprockets

28 and 28 by a pair of

idler rollers

71 and 72, the idler roller 72 being carried by a bracket 75 which is secured by screws 76 to the machine frame while the idler roller 71 is carried by a bracket 80 secured by screws 81 to the loop taker saddle 21 The arrangement of timing belt 70, as illustrated in the accompanying drawings, provides for a shift of the loop taker saddle positions equidistant from a medial plane X-X between the needles 16 without the necessity for disturbing the loop taker drive. Furthermore, this belt drive provides for simultaneously reestablishing timed relations of both loop takers with their respective needles after a position adjustment by adjustment of one connection in the drive train such as the driving sprocket 57 relatively to the shaft 53. A copending U.S. Pat. application Ser. No. 43,061, filed June 3, i970, Reinhold Papajewski, having a common assignee may be referred to for a description in greater detail of this loop taker drive mechanism.

The operation of the present loop taker saddle support will be apparent from the following description of the steps involved in adjusting the loop taker saddles 21 of FIGS. 1 and 3 to accommodate a greater needle spacing. Assuming that the needle clamp 15 and throat plate have been changed, the clamp screw 37' as first loosened so that the recessed way 34 will no longer be deflected. The loop taker saddle 21' therefore will be freed for shift along the ways 34. Preferably, the loop taker saddle 21 will be shifted into the new position using a gauge block to obtain an accurate setting. Since the clamp screw 37' does not engage the guide surface 35' of the way 34, the way will not be scored or otherwise marred by a previous clamping and even the smallest adjustment of position can be effected. When in desired new position, the loop taker saddle 21' is clamped in place by tightening the screw 37. The belt 70 will have been loosened by the shift of the loop taker saddle 21' to the right as viewed in FIGS. 1 and 3, however, the loop taker saddle 21" is then shifted a like amount to the left by the same process which tightens the belt to the original state of tension. As explained in detail in the above referred to copending U.S. Pat. application, the loop takers, after being adjusted into new positions, may simultaneously be retimed relatively to the needles by adjusting the driving sprocket 57 relatively to the shaft 53 on which it is carried.

Having set forth the nature of this invention, what is claimed herein is:

1. Mechanism for supporting and clamping a loop taker saddle in the frame of a sewing machine comprising a pair of elongate ways, means for securing said ways in spaced substantially parallel relation in said sewing machine frame, said loop taker saddle being formed with spaced channels each embracing one of said ways slidably to support said saddle in said sewing machine frame, and means carried by said sewing machine frame for deflecting at least a portion of one of said ways toward the space between said ways to clamp the loop taker saddle in selected position between said ways.

2. Mechanism for supporting and clamping a loop taker saddlein the frame of a sewing machine as set forth in claim 1 in which said ways comprise elongate bars formed at one side with a saddle channel engaging surface which is substantially uniform in cross-sectional configuration along the entire length of said ways, in which at least one of said ways is formed along the side opposite said saddle channel engaging surface with a recess extending along a portion of the length of said way and disposed in spaced relation to said sewing machine frame when said way is secured thereto, and in which said deflecting means comprises an adjusting screw threaded into said sewing machine frame and impinging upon said recessed portion of said at least one way.

Claims

2. Mechanism for supporting and clamping a loop taker saddle in the frame of a sewing machine as set forth in claim 1 in which said ways comprise elongate bars formed at one side with a saddle channel engaging surface which is substantially uniform in cross-sectional configuration along the entire length of said ways, in which at least one of said ways is formed along the side opposite said saddle channel engaging surface with a recess extending along a portion of the length of said way and disposed in spaced relation to said sewing machine frame when said way is secured thereto, and in which said deflecting means comprises an adjusting screw threaded into said sewing machine frame and impinging upon said recessed portion of said at least one way.