US3221573A

US3221573A - Adjusting device for regulating a sewing machine mechanism

Info

Publication number: US3221573A
Application number: US222302A
Authority: US
Inventors: Bono Luigi
Original assignee: Necchi SpA
Current assignee: Necchi SpA
Priority date: 1962-01-03
Filing date: 1962-09-10
Publication date: 1965-12-07
Anticipated expiration: 1982-12-07
Also published as: GB1015903A; AT240682B

Description

L. BONO Dec. 7, 1965 ADJUSTING DEVICE FOR REGULATING A SEWING MACHINE MECHANISM Filed Sept. 10, 1962 2 Sheets-Sheet 1 INVENTOR BO N O LU IGI BY #P ATTORNEYEL BONO 3,221,573

ADJUSTING DEVICE FOR REGULATING A SEWING MACHINE MECHANISM Dec. 7, 1965 2 Sheets-Sheet 2 Filed Sept. 10, 1962 VIIIIIIIIII ATTORNEYS United States Patent ADJUSTING DEVECE FUR REGULATHNG A SEWING MACHINE MECHANIM Luigi Bone, Pavia, italy, assignor to Necchi Societa per Azioni, Pavia, Italy Filed Sept. 10, 1962, Ser. No. 222,302 Claims priority, application ltaly, Jan. 3, 1962, Patent 672,952 9 Claims. (Cl. 74-522) This invention relates in general to new and useful improvements in adjusting devices for regulating mechanisms of sewing machines, and more particularly relates to a device for the disengaging, engaging and micrometric regulation of the connection between a cam and a member regulating the feeding movement of the feed dog of a sewing machine.

A primary object of the invention is to provide a device with two different operating means so that the first of the operating means can be maneuvered between two extreme positions corresponding to the total engagement and total disengagement movement of the connection between a cam and a regulating member, and the second operating means being intended to permit micrometrical regulation of the apparatus controlling the movement which the cam transmits to the regulating member in such a manner that operates of sewing machines desiring to provide for very minute adjustment of the sewing machine can correct the small errors in sewing due to the play within the various control members of the sewing machine as well as the inevitable differences in the profile in cams from the theoretical dimensions thereof.

In accordance with this invention, it is also required that when the first operating means is in the extreme position corresponding to the disengagement position of the connection between the cam and the regulating member, the regulating member is in a Well-defined rest position regardless of the position assumed by the second operating means. In particular, it is another object of the invention to make it possible that when the first operating means is in the extreme position corresponding to the disengagement position of the regulating member, the regulating means is in an intermediate position between its camcontrolled position and that there is provided stop means movable with the first operating means and capable of stopping the regulating member in its rest position.

Another object of this invention is to provide a lever type control for varying the effect of a cam on an operating mechanism, the lever type control including a lever having a cam follower or feeler for engagement with a cam, and the lever being mounted on a second lever which is swinga-ble to vary the pivot point of the first lever to either selectively render the cam ineffective with respect to the first lever, or to drive the first lever from the cam, and to micrometrically vary the position of the first lever to effect a minute adjustment thereof.

Other objects of this invention will become more clearly evident from the following description and from the accompanying drawings which show by way of illustration a preferred embodiment of the invention in use in the regulation of the amplitude and direction of the lateral feed movement of the feed dog of a sewing machine in which the feed dog, in addition to its traditional movements of advancing in longitudinal direction, can carry out feed movements in a lateral direction.

The structure of this application constitutes an improvement in the sewing machine described in my copending application, Patent No. 3,096,737, issued July 9, 1963.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views ilvention, with the regulating mechanism being shown in an engaged position.

FIGURE 2 is an enlarged fragmentary vertical sectional view taken along the line IIII of FIGURE 1, and shows more specifically the details of one of the adjustmerits of the regulating mechanism.

FIGURE 3 is an enlarged fragmentary vertical sectional view taken along the line III--III of FIGURE 1, and shows the details of another of the adjustment means of the regulating mechanism.

FIGURE 4 is an enlarged fragmentary vertical sectional view showing the details of the adjustment means of FIGURE 3.

FIGURE 5 is an enlarged bottom view of the mechanism shown in FIGURE 3.

FIGURE 6 is a fragmentary enlarged elevational view of a portion of the mechanism of FIGURE 3.

FIGURE 7 is an enlarged fragmentary bottom view showing in more detail the control mechanism of FIG- URE 1, with the mechanism in its disengaged position.

FIGURE 8 is a schematic representation of the various controls.

From the following description and the accompanying drawings, it will be clear that the invention relates substantially to the use of a lever which is slidably connected with a regulating member for regulating the amplitude and direction of the lateral advancing movements of a feed dog, and which lever is pivoted on a second lever which is pivoted to the frame of the sewing machine and which has a slidable contact connection with the small end of a connecting rod. The connecting rod is, in turn, provided with an eccentric big end on the axis of an operating member coaxial with a second operating membcr which is journaled in the frame of the sewing machine and which has a groove along which the small end of the connecting rod is guided. The second operating means is rotatable within its own bushing between two end positions so that the small end of the connecting rod is movable within a circular, annular sector coaxial to the two operating means.

Reference is first made to FIGURE 1 of the drawing wherein there is illustrated a conventional type of feed dog 1 which is arranged opposite the :slot of a needle plate (not shown) which is conventionally fastened to the frame of a sewing machine, the frame being referred to by the numeral 2.

The feed dog 1 is suitably secured to a support 3 by means of screws 4 and receives the customary raising and lowering movements within the customary slots of the needle plate from an eccentric 5 which is rigidly fastened to a rotating shaft 6.

A pin '7 having a horizontal axis is secured to the support 3 by means of a pin 8. The pin 7 is journaled in the arms 9 of the lever 10, which, in turn, is rigidly fastened to a shaft 11 pivoted in the frame 2. The shaft 11 is driven in a conventional manner not forming a part of this invention to have oscillating movements of adjustable amplitude, which movements determine the movement of advance of the feed dog 1 in a longitudinal direction indicated by the arrow x. The feed dog 1 is also subject to movement of advance in a lateral direct-ion y synchronous with movements in a longitudinal direction x. On one end of the pin 7 there is mounted a small block 12 which has a groove 13 disposed perpendicular to the axis of the pin 7. A plug 14 carried by a lever 15 is disposed within the groove 13 :so as to effect the longitudinal shifting movement of the pin 7, the support 3 3 carried thereby and the feed dog 1. The lever is provided at the opposite ends thereof with pins 16 and 17 with the pin 16 being carried by a plate 18 suitably secured to the frame 2 of the sewing machine and forming the pivot for the lever 15. The pin 17 serves to pivotally connect the lever 15 to one end of another lever 19.

A regulating member is pivoted to the lever 19 adjacent the opposite end thereof. The regulating member 20 consists of a small block 21 (FIGURE 2) which is fastened to a guide 22 by a setscrew 23. The guide 22 is in the form of an elongated rod which is mounted for sliding movement in holes 24 of two bent arms of a rocker 26.

As is clearly shown in FIGURES 1 and 2, the rocker 26 has a vertical pivot 27 which is rotatably journaled within a bushing 28. The bushing 28 is welded to a plate 29 which, in its turn, is fastened to the frame 2 by screws 30. The rocker 26 rocks about its own pivot 27 with respect to which the two arms are symmetrically disposed. The rocking of the rocker 26 is effected by means of a feeler or cam follower 31 which is fastened to a plate 32 rigidly connected to the rocker 26 and which bears against a front profiled part of a cam 33. The cam 33 is secured to the rotating shaft 6 for movement therewith.

The connection between the cam follower 3i and the cam 33 is assured by means of a spring 34 which is fastened to a pin 35 of the plate 32 and to a second pin 36 which is suitably carried by the frame 2.

The amplitude and direction of the oscillations of the block 21 depend, of course, on its position with respect to the axis of the fulcrum 27. These oscillations of the block 21 are transmitted to the feed dog 1 so as to control the feed movement of the fabric in the lateral direction y.

The combination of the feed movements of the feed dog 1 in the two directions x and y obviously provide for the feeding of fabric in any desired direction.

In order to control the position of the block 21 with respect to the arms 25 and the rocker 26, the block 21 is connected in a slidable fashion with an assembly 37. The slidable connection between the lever assembly 37 and the block 21 is effected by means of a pin 38 carried by the lever assembly 37 and which is engaged in a fork 39 secured on the end of the lever 19 remote from the pin 17.

The lever assembly 37 consists of two

arms

40 and 41, the position of which with respect to each other can be adjusted. The arm 41 is rigidly connected by means of a pin 42 with a plate 43, while the arm 40 is pivoted on the pin 42 and is fastened to the plate 43 by a screw 44 which is engaged in a slot 44 on the arm 40. An eccentric 45 is carried by the plate 43 and is mounted in a slot 46 in the arm 48. The position of the two

arms

40 and 41 is regulated by means of the eccentric 45, and they are rendered solid as between themselves by means of the screw 44 which is engaged in the slot 44' of the arm 40. After the plate 43 has been adjusted relative to the arm 40, to effect the adjustment of the arm 41 with respect to the arm 40, the plate 43 is locked in adjusted position relative to the arm 40 by means of the screw 44.

The arm 41 carries a feeler or cam follower 47 which is engageable with an interchangeable cam 48. The cam 48 is mounted within the frame 2 and driven in the customary manner of the cam for controlling the transverse oscillations of feed dogs and accordingly the manner in which the cam 48 is driven and interchanged is not described here. A spring 49 is fastened to a tongue 50 of the arm 40 at one end and to a pin 51 carried by the frame 2 at the opposite end so as to urge the cam follower 47 into engagement with the cam 48.

The specific details of the invention include a device for engaging, disengaging and micrometrically regulating the connection between the cam follower 47 and the cam 48. This device includes the pin 42 which serves to pivot the lever assembly 37 on a second lever 52, which in its turn is pivoted to the frame 2 by a pin 53, as is best shown in FIGURE 3. A plate 54 is secured to the frame 2 by a screw 55 and prevents the lever 52 from sliding axially along the pin 53.

As is best shown in FIGURES 4 and 5, there is a slidable connection between the lever 52 and a small end 56 of a small connecting rod 57. The connecting rod 57 also has an eccentric big end 58 disposed along the axis of an operating member 59. The slidable connection between the lever 52 and the small end 56 of the connecting rod 57 includes a fork 68 which is provided on an arm 61 of the lever 52 and which surrounds a pin 62 rigidly connected to the small end 56 of the connecting rod 57. The big end 58 of the connecting rod 57 is pivoted on a pin 63 which is disposed eccentric with respect to the axis of the operating member 59. A locking ring 64 is engaged in a groove 65 of the pin 63 to hold the connecting rod 57 in contact with a shoulder 66 of the operating member 59.

The small end 56 of the connecting rod 57 is guided between

parallel walls

67 and 68 of a groove which is provided on the lower end of a second operating member 69 (FIGURE 5). The operating member 69 is disposed coaxial with the operating member 59 and is rotatably journaled on a bushing 76 rigidly connected with the frame 2 of the sewing machine.

The rotation of the operating member 59 permits the small end 56 of the connecting rod 57, and therefore the pin 62, to vary its position within the groove defined by the

walls

67 and 68 of the operating member 69. The rotation of operating member 69, however, makes it possible to vary the orientation of the groove defined by the

walls

67 and 68 so that the combined operation of the two operating

members

59 and 69 permits the pin 62 to move within an annular circular sector, the angular extent of which is determined by the rotations which the operating member 69 can undergo between the two end positions a and b which will be defined hereinafter.

In FIGURE 4, the members which permit the rotation of the operating

members

59 and 69 include a knob 71 secured to the operating member 59 and a handle 72 secured to the operating member 69. The handle 72 is disposed beneath the knob 71 and is secured to the operating member 69 by means of a key 73 which is engaged in an axial groove 74 in the operating member 69. An elastic washer 75 is disposed between the knob 71 and the handle 72 so as to frictionally connect the knob and the handle and at the same time, to hold upwardly the operating member 59 within the bushing. The upward holding of the operating member 59 results in the upward holding of the connecting rod 57 and the operating member 69 so that the shoulder 76 of the operating member 69 is forced toward a shoulder 77 of the bushing in the manner best illustrated in FIGURE 6.

In FIGURE 6, there are illustrated the stop means for defining the two end positions a and b between which the operating member 69 can rotate. The stop means are shown, by way of example, as including one or more circular grooves 78 formed on the front side of the shoulder 76 of the operating member 69. Front teeth 79 protruding from the shoulder 77 of the bushing 70 engage Within the grooves 78. The circular grooves 78 and the teeth 79 are so dimensioned to permit the operating member 69 to rotate together with the handle 72 between two end positions a and b which are substantially perpendicular to each other. When the handle 72 is in the position a, with reference to FIGURES 7 and 8, the operating member 69 is so oriented that the

walls

67 and 68 are parallel to the fork 66 of the lever 52. Any manipulation of the knob 71 of the operating member 59 now has solely the effect of displacing the pin 62 along the fork 60 of the lever 52 and the lever 52 holds the pin 42 stationary in the position 0 indicated by solid lines in FIGURE 8. When the handle 72 is in position b, the operating member 69 is so oriented that the

walls

67 and 68 are substantially perpendicular to the fork 60, as is indicated by dotted lines in FIGURE 8. In this position of the device, the operating member 59 can be utilized to micrometrically adjust the position of the lever 52 in such a manner that the pin 42 can be moved in the vicinity z of a central position d shown in FIGURE 8. It is obvious that for any intermediate position of the handle 72 and therefore of the operating member 69 between the end positions a and b, the operating member 59 permits micrometric adjustment of the position of the pin 42 in the vicinity of a corresponding position intermediate between the positions 0 and d.

In accordance with the preferred embodiment of the invention, engagement means are provided between the operating member 69 and the frame 2 of the sewing machine so as to define the positions in which the operating member 69 can be rotated. In FIGURE 6, the engagement means are represented by an equal number of deep indentations 80 in the grooves 78 as angular positions into which it is desired to position the operating member 69. The teeth 79, by engaging in the indentations 80, prevent the rotations of the operating member 69. In order to rotate the operating member 69 from one position to another, pressure is exerted in an axial direction on the knob 71 so that the shoulder 81 thereof presses on the upper surface 82 of the operating member 69, as is shown in FIGURE 4. The operating member 69 then slides downwardly with respect to the handle 72 and the bushing 70 so that the teeth 79 disengage from the indentations 80. The handle 72 is now rotated in such a manner that the key 73 thereof pulls the operating member 69 into the desired new angular position. Upon releasing the knob 71, the elastic washer 75 pulls the operating member 69 back in an upward direction and the teeth 79 which are moved over the bottom wall of the groove 78 engage in the new indentations 88.

When the knob 71 is pressed downward so as to disengage the teeth 79 from the indentations 8i and as long as the teeth 79 press against the bottom wall of the groove 78, the elastic washer 75 so acts between the knob 71 and the handle 72 to prevent the knob and the handle from undergoing rotation relative to one another. This makes it possible to rotate the operating member 69 without the position of the pin 62 being changed between the

walls

67 and 68. In this way, there can be carried out as many manipulations of the operating member 69 as desired, while retaining the adjustment of the position of the pin 62.

In accordance with the invention, it is generally required that the operating member 69, when it is in its end position a be accompanied by the position of the pin 42 in the position 0 so that the spring 49 which pulls the lever assembly 37 against the stop surface 83 can disengage the connection between the lever 41 and the cam 48, as is shown in FIGURE 8. The lever assembly 37 is thus stopped in a position corresponding to a well defined position of the regulating member 20.

It is also necessary that when the operating member 69 is in the end position b, the pin 42 be in the vicinity z of a position d such that the connection between the cam 48 and the lever 41 is effected, whereby the oscillations of the lever assembly 37 can bring about corresponding oscillations of the regulating member 28.

With respect to the intermediate positions of the operating member 69 between the positions a and b, there is obviously a partial connection between the lever assembly 37 and the cam 48.

In the special arrangement shown in the drawings, it is necessary that the operating member 69 be positionable only in the two end positions a and b to which there corresponds the positions of disengagement and engagement of the connection between the cam 48 and the lever asesmbly 37. Accordingly, there are only two indentations for each groove 78 with the indentations 80 being arranged at the ends of the grooves 78.

It is further necessary that when the connection between the cam 48 and the lever assembly 37 is effected, the lever 37 can displace the block 21 between the arms 25 of the rocker 26 from both sides with respect to the pin 27. However, when the connection between the lever assembly 37 and the cam 48 is disengaged, the lever assembly 37 must be stopped in such a position so as to maintain the block 21 in alignment with the axis of the pin 27 of the rocker 26. In this way, the oscillation of the rocker 26 will not be transmitted to the feed dog 1 and the feed movements of the feed dog 1 in. the lateral direction y will be fully cancelled out. In order to satisfy these last conditions, it is necessary that the stop surface 83 be arranged in such a manner that it is brought into a position of interference with the lever 37 only when the pin 42 is in the position 0.

In the drawings, the stop surface 83 consists of a wall of the lever 52 which is contacted by an eccentric 84 carried by the arm 40 of the lever assembly 37. The eccentric 84 has a groove which is visible and which makes it possible to adjust the angular position of the eccentric 84. After the position of the eccentric 84 has been adjusted, it is tightened in its adjusted position by means of a screw 86.

When the handle 72 of the operating member 69 is in the position a, the eccentric 84 presses against the stop surface 83 of the lever 52 and releases the connection between the lever 37 and the cam 48. The engagement of the eccentric 84 with the stop surface 83 locks the lever assembly 37 in the position indicated by solid lines in FIGURE 7 so as to hold the block 21 aligned with the axis of the pin 27, as is shown in FIGURE 2. However, when the handle 72 is in the position b, the stop surface 83 has moved away from the eccentric 84 so that the lever assembly 37 is free to follow the profile of the cam 48 and to bring the block 21 into any position between the arms 25 of the rocker 26. The connection between the cam 48 and the lever assembly 37 can now be adjusted miorometrically by the operating member 59, which makes it possible to vary the position of the pin 42 in the vicinity z of the central position d.

It is obvious that in order to effect the displacement of the pin 42 within the vicinity z of the position d, it is sufiicient that the operating member 59 rotate through a slight angle so as to bring the small end 56 of the connecting rod 57 from one of its dead center positions to the other within the groove defined by the

walls

67 and 68 of the operating member 69. In accordance with the preferred embodiment of the invention, as shown in FIG- URE 5, the connecting rod 57 has a flat wall 87 such that by adhereing to the wall 68 of the groove in the operating member 69, limits to a predetermined angular adjustment the possible rotation of the operating member 59 with respect to the operating member 69. The other wall 67 of the groove in the operating member 69 is disposed opposite the big end 58 of the connecting rod 57 so as to permit the necessary movement of the connecting rod 57 to bring the small end 56 thereof from one of its dead center positions to the other.

Although only a preferred embodiment of the invention has been illustrated and described herein, it is to be understood that minor variations in the invention may be made within the spirit and scope of the invention, as defined by the appended claims.

I claim:

1. Adjusting device for regulating a sewing machine mechanism comprising a first lever, an actuating member, said device further comprising a second lever having first and second arms and a central pivot, a pivot for the first mentioned lever carried by said second arm, and a control device connected with the first. arm to effect the shifting of said first lever pivot, said control device including shift means for moving said first arm between positions where said first lever is engaged and disengaged from the actuating member, and adjustable means for limiting the mottion of said shift means, said shift means and said last means including concentric control shafts, a connecting rod carried by one of said control shafts, and means on the other control shaft for permitting limited relative movement of the connecting rod by the one control shaft.

2. Adjusting device for regulating a sewing machine mechanism comprising a first lever, an actuating member, said device further comprising a second lever having first and second arms and a central pivot, a pivot for the first mentioned lever carried by said second arm, and a control device connected with the first arm to effect the shifting of said first lever pivot, said control device including shift means for moving said first arm between positions where said first lever is engaged and disengaged from the actuating member, and adjustable means for limiting the motion of said shift means, said shift means and said last-named means including concentric control shafts, a connecting rod eccentrically carried by an inner one of said control shafts, and the outer one of said control shafts having a slotted portion receiving the connecting rod and being shaped to permit movement of said conmeeting rod by said inner shaft independently of movement of said outer shaft, and means normally connecting together said control shafts for movement in unison.

3. The device of claim 2 wherein the relative movement permitted by said outer shaft slot is ineffective to shift said first lever into engagement with the actuating member in the disengaged position of the shift means.

4. The device of claim 2 wherein said connecting rod carries a pin engaged in a slot in said first arm, and wherein the effective movement of said connecting rod by said inner shaft is in the direction of said first arm slot in the lever disengaging position of the control device 8 efi ected by rotaton of said outer shaft, and the effective movement of said connecting rod by said inner shaft is generally normal to the direction of said first arm slot in the lever engaging position.

5. The device of claim 2 together with cooperating stop means on said first arm and said first lever to assure a predetermined position of said first lever in the disengaged position thereof.

6. The device of claim 2 together with a shiftable control unit operatively connected to and operated by said first lever and having a central inactive position, and cooperating means on said first arm and said first lever for positioning said first lever and said shiftable control unit in said central inactive position when said first lever is moved to its disengaged position.

'7. The device of claim 6 wherein said cooperating means include an eccentrically mounted stop member.

8. The device of claim 6 wherein said first lever includes two arms releasably and adjustably connected together and independently pivotable about said first lever pivot when released.

9. The device of claim 6 wherein said shiftable control unit is engaged with a cam and connected with linkage for effecting the transverse movement of a sewing machine fabric feed dog, and said first lever is effective to shift said shiftable control unit to vary the amplitude of the driving of said feed dog from said cam from zero to a predetermined maximum.

References Cited by the Examiner UNITED STATES PATENTS 1,892,765 1/1933 Howard. 2,410,708 11/1946 Breithcr et a]. 3,096,737 7/1963 Bono.

BROUGHTON G. DURHAM, Primary Examiner.

Claims

1. ADJUSTING DEVICE FOR REGULATING A SEWING MACHINE MECHANISM COMPRISING A FIRST LEVER, AN ACTUATING MEMBER, SAID DEVICE FURTHER COMPRISING A SECOND LEVER HAVING FIRST AND SECOND ARMS AND A CENTRAL PIVOT, A PIVOT FOR THE FIRST MENTIONED LEVER CARRIED BY SAID SECOND ARM, AND A CONTROL DEVICE CONNECTED WITH THE FIRST ARM TO EFFECT THE SHIFTING OF SAID FIRST LEVER PIVOT, SAID CONTROL DEVICE INCLUDING SHIFT MEANS FOR MOVING SAID FIRST ARM BETWEEN POSITIONS WHERE SAID FIRST LEVER IS ENGAGED AND DISENGAGED FROM THE ACTUATING MEMBER, AND ADJUSTABLE MEANS FOR LIMITING THE MOTION OF SAID SHIFT MEANS, SAID SHIFT MEANS AND SAID LAST MEANS INCLUDING CONCENTRIC CONTROL SHAFTS, A CONNECTING ROD CARRIED BY ONE OF SAID CONTROL SHAFTS, AND MEANS ON THE OTHER CONTROL SHAFT FOR PERMITTING LIMITED RELATIVE MOVEMENT OF THE CONNECTING ROD BY THE ONE CONTROL SHAFT.