US2553211A

US2553211A - Control means for sewing machines

Info

Publication number: US2553211A
Application number: US642642A
Authority: US
Inventors: Rothenborg Aage; Eriksson Allan Herman; Magnusson Bengt Arne
Original assignee: Husqvarna Vapenfabriks AB
Current assignee: Husqvarna Vapenfabriks AB
Priority date: 1944-12-29
Filing date: 1946-01-22
Publication date: 1951-05-15
Anticipated expiration: 1968-05-15

Description

May 15, 1951 A. ROTHENBORG ETAL 2,553,211

CONTROL MEANS FOR SEWING MACHINES Filed Jan. 22, 194e z sheets-'sheet 1 v Lw/'12u67 May 15, 1951 A. ROTHENBORG ET AL 2,553,211

CONTROL MEANS FOR SEWING MACHINES Filed Jan. 22, 1946 -2 Sheets-Sheet 2 Patented May 15, 1951 CONTRL MEANS FOR SEWING MACHINES Aage Rothenburg, Hellerup, Denmark, and Allan Herman Eriksson and Bengt Arne Magnusson, Huskvarna, Sweden, assignors to Husqvarna Vapenfabriks Aktiebolag, Huskvarna, Sweden,

a corporation of Sweden Application January 2.2, 1946, Serial No. 642,642 In Sweden December 29, 1944 7 Claims. (Cl. 112-158) In certain kinds of work, such as embroidery work, which are performed by means of Zig-Zag sewing machines, it is desirable that both hands be free as far as possible to keep and guide the work. The present invention has for its object to provide an arrangement facilitating such operations, the same being devised to permit the performance of certain operating movements by the knee of the operator.

A substantial characteristic feature of the invention resides primarily in the combination of an operating member adapted to be actuated by the knee of the operator with a coupling member adapted to be coupled at will, to certain operated means, such as the lifting means of the presser foot, when this is desired, or to means for the control of the needle bar amplitude, when this is desired. Consequently, the invention permits not only the governing of a certain movement with the aid of the knee, but also the selection of an arbitrary one of two or more dierent operating movements and their coupling to the operating member through the actuation of a coupling member. The operating movements primarily brought into consideration refer to the movement of the presser foot bar at the lifting of the presser foot and to the actuation of the zig-Zag mechanism for the control of the width of the zig-zag seam (the amplitude of the oscillatory movement of the needle bar).

Further features characteristic of the invention and advantages inherent therein will appear from the following description of two embodiments illustrated in the accompanying drawing, said embodiments being intended to serve as an elucidating example. The drawing shows parts of a Zig-Zag sewing machine with a device according to the invention mounted thereon, Figs. 1-3 of one embodiment, Fig. l being a front elevation, Fig. 2 a plan view, and Fig. 3 an end view, partly in a vertical cross section through the housing of the sewing machine, and Figs. 4-7 of the other embodiment, Fig. 4 showing a iront elevation of a zig-zag sewing machine provided with the operating device, and Fig. 5 being a vertical section on line A-A in Fig. 4. Figs. 6 and 7 show a detail in section on lines C-C and D-D in Fig. 5, respectively. Figs. 8 and 9 are cross sections of a detail of the control means showing two different positions of the parts.

As shown in Figs. 1-3, the operating member may consist of a bell crank lever 3 provided with a supporting plate I for the knee 2 of the operator, said bell crank lever being mounted on a` xed stud 4 and connected with the one end of a CII link rod 5, the other end of which is pivotally connected to a supporting member or an arm 6 constituting the one lever arm of a bell crank lever, the other arm of which is designated by '1. The bell crank lever 6, l is mounted concentrically to a shaft 8, preferably on a bearing bushing 9 arranged thereon, said bushing being fitted into the wall lil of the housing of the sewing machine. The shaft 8 is coupled, by means of arrangements not shown in the drawing, to the mechanism effecting the zig-zag movement of the sewing machine, in a manner such that the amplitude of the Zig-Zag movement or the width of the seam is controlled by a turning movement of said shaft. An example of such a mechanism will be found in the co-pending patent application Serial No. 648,183, iled February 16, 1946.

An arm II is mounted concentrically with the shaft 8, preferably on the bushing 9, said arm being connected through a link rod I2' to the one arm of a bell crank lever i5 mounted on a xed stud I4, the other arm of said bell crank lever cooperating with a lifting block I5 coupled to the presser foot bar I'I.

The operating member may be coupled to the shaft 8 or to the described mechanism for raising the presser foot bar, said coupling being effected by means of a coupling member consisting of a carrier I9 mounted on a stud I8 in a slot in the arm 1. The carrier i9 is made as a double-armed lever, one arm of which is provided with a carrier abutment Z, which may be brought into engagement with a recess 2| in a flange 22 secured on the shaft 8, and the other arm of which has a carrier abutment 23 for cooperation with a slot 24 in the arm I I pertaining to the lifting device of the presser foot bar.

The device operates in the following manner:

According to Figs. 3 and 8, the upper arm of the carrier I9 is depressed, so that the abutment 23 is introduced into the slot 2li of the arm II, while the abutment 20 on the lower arm of the carrier is out of engagement with the recess 2| in the flange 22. lf the operating member is actuated by the supporting plate I being moved by the knee 2 to the left in Fig. l, the rod 5 will be displaced upward by the bell crank lever 3, so that the bell crank lever 6, 'l is turned in a counter-clockwise direction. The carrier I9 then carries the arm I I along with it by means of the abutment 23, said arm then pulling the link rod I2 to the left, whereby the bell crank lever I5 is turned in a counter-clockwise direction and moves the lifting block I6 so as to press the rod Vhandle 8a in Fig. 5, in such manner that the recess 2| is brought opposite the abutment 23), whereby the arm 1 is coupled to the shaft .8. At the same time the abutment v23 on the upper arm of the carrier is moved out of the slot 2'4, so that the connection with the lifting device of the presser bar is interrupted. The shaft 48 can now be turned with the aid of the operating device by the supporting plate being actuated by means Aof the knee, whereby the Width of the seam is varied.

The invention is not limited to the details illustrated in Figs. 1 to 3, but includes many variations and modifications. For example, a somewhat simpler construction can be obtained by using the embodiment illustrated in Figs. 4 to y1, in which the coupling member is formed asa link connection between the control operating means and -the lever for the presser foot vlifting member.

As illustrated in Figs. 4 to 6 5 designates the link rod which is included in the operating device which comprises a lever system of the type illustrated in Fig. 1, the upper end of the link rod being connected with the one .end of a ldoublearmed lever 6. The lever is ymounted concentrically with a regulating shaft 8 pertaining to the means for regulating the amplitude of the needle bar and the width of the seam, said lever being carried on the bushing or sleeve 9 which is rotatably arranged on said shaft and'rotatably fitted into a bearing 41 in the wall l0'of the housing of the sewing machine. The presser foot bar |'1 may .be raised with the aid of the lever I5' which is pivotally mounted on a stud 15a in the housing of the machine, one arm of said lever being in engagement with a lifting block I6 arranged on the presser foot bar. One .end of a link I9' is swingably mounted on a stud IB on the upper arm of the supporting member or lever in the figure, the other end of said link forming a connection with one or the other of the members to be operated, said connection being adapted to be released. `According to the drawing, the link i9 is formed to a hook, which in the position shown by ifull lines grasps about the projecting end :portion I5b of the Ylever I5', but which is adapted to be swung rearward, .so that a shoulder I9a on the edgethereof is brought into engagement with a projection 44 ,on that end of the sleeve 9 which projects from the machine housing (dotted lines in Fig. 4). By the fact that the hook is swung over ,in this manner, the connection of the operatingmember Withthe pressel` foot bar is interrupted, and ,instead the operating member is coupled tothe means for regulating the seam width,

The width of the seam is .regulated .manually by turning the shaft' by means of a handle 8a,

when is secured on the shaft L8'. When operation is effected by the knee, the turning movement of the sleeve 9' is transmitted to the shaft 8 through a friction coupling consisting of a spring plate li, which :is non-rotatably secured to the end of the shaft 8 and bears with .its edge on the end surface of .the sleeve 9'.

A return spring 43 inserted between the bottom of the machine frame, on the one hand, and a clamping ring 9a surrounding the sleeve, on the other hand, tends to keep the sleeve 9' in an angular position, where a pair of abutments 45 on the end of the sleeve 9' are in engagement with corresponding fixed abutments 46 on the stationary bearing 41 surrounding the sleeve. When the link rod 5 is pressed upward by the 0perating member, the lever 6 turns about the sleeve 9', so that the link I9', if coupled to the lever i5', causes the latter to lift the presser foot bar. On the other hand, if the operating member is actuated to lift the rod 5, after the link i9 has been swung over into the position indicated by dotted lines in Fig. 4, wherein the shoulder lSa is in engagement with the projection 44, the link I9 will entrain the sleeve, when it is swung by the lever 6 about the center of the shaft 8', the spring 43 being thus tensioned. The sleeve 8 entrains .in turn 'the shaft .'8' over the friction coupling 40, by means `of .which shaft the width of the seam is regulated.' After the operating member has been released upon such a movement of adjustment, the sleeve 5' is turned back into the initial position with the aid `of the return spring 43.

What we claim is:

l. A control means for zig-zag vsewing imachines having a presser foot, a lifting mechanism for the presser foot and an oscillatory needle operating mechanism, comprising an operating member adapted to be actuated by the knee of the operator, and a coupling member adapted .to couple the operating member at will alternatively to the presser foot lifting mechanism and vto :the needle operating mechanism to enable liftingof the presser foot or adjustment of the needle .amplitude by the knee.

2. A control means forzig-zag sewing machines having a housing, a presser foot, alifting mechanism for the presser foot, an oscillatory needle operating mechanism comprising a .shaft journalled in the housing, an operating member adapted to be actuated by the knee of .the Yoperator and comprising a bell crank klever 'jour-V nalled coaxially Ywith said shaft, .and a :coupling member for cooperation with said lever to Iconnect the leyer with the presser foot v.lifting mechanism or with the shaft alternatively at will, whereby the presser foot may be liftedor .the .amplitude of the oscillatory needle may be adjusted at desired moments.

3. A control means as claimed .in claim 2 'in which the coupling member comprises acarrier pivoted to the bell crank lever and provided with abutments, and in which a nange is attached to the shaft and has a recess, and the presser vfoot lifting mechanism comprises an arm rotatably mounted on the shaft and having a slot .formed therein, one of said abutments beingadapted-to be engaged with the recess and another of the abutments being adapted to Vcooperate with'the slot of the arm.

4. An operating device for Zig-zag sewing machines comprising an operating member adapted to be actuated by the knee of the operator, mechanisms adapted to be operated by said operating member, a coupling means adapted to connect the operating member with said mechanisms alternatively at will, said coupling means comprising a supporting member and a link 4pivoted at one end to said supporting member -a-nd adapted to be engaged selectively with `one of said mechanisms.

5. A control means for zig-zag sewing machines having a housing, a presser foot lifting mechanism comprising a, lever pivoted to the housing and an oscillatory needle operating mechanism, comprising means to adjust the amplitude of the needle operating mechanism, said means comprising a shaft, a bushing or sleeve rotatably journalled in the housing and having a projection and means to connect the bushing with the shaft, an operating device for selective operation of said mechanisms, said device comprising a supporting member and a hook-shaped link pivoted to said supporting member at its one end and adapted to be connected with one end of said lever or to be turned over and disengaged with said lever end to engage the projection on the sleeve or bushing.

6. A control means as claimed in claim 5 having abutments on the rotatable sleeve, corresponding to iixed abutments for determining an initial position of the operating device, and a restoring spring connected with the sleeve to keep the same resiliently in its initial position.

7. In a zig-zag sewing machine having a hous- REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 608,553 Mack Aug. 2, 1898 1,823,817 Christensen Sept. 15, 1931