US1120722A

US1120722A - Embroidering-machine.

Info

Publication number: US1120722A
Application number: US79630513A
Authority: US
Inventors: Johann Jacob Knecht
Original assignee: KAPPEL A G MASCHF
Current assignee: MASCHINENFABRIK KAPPEL AG; KAPPEL A G MASCHF
Priority date: 1913-10-20
Filing date: 1913-10-20
Publication date: 1914-12-15
Anticipated expiration: 1931-12-15

Description

J. J. KNEGHT.

BMBROIDERING MACHINE.

APPLICATION FILED 00120. 1913.

1,120,722, Patented Dec. 15, 1914.

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iinrrnn stares raannr canton JGHANN JACOB KNECHT, OF KAPPEL, NEAR- CHEMNITZ, GERT/IANY, ASSIGNOR TO THE FIRM OF MASCHINENFABR NITZ, GERMANY.

K KAPPEL A. (3., OF 11.

rest, NEAR enem- EMBROIDEEING-1VIAGHINE.

Application filed October 28, 1918.

To all whom it may concern:

Be it known that I, JOI-IANN Jason KM: rrr, a citizen of the Confederation of Switzerland, and resident of .Kappel, ncar Chemnitz, in the Kingdom of Saxony, Germany, have invented certain new and useful Improvements in Embroidering- Machines, of which the following is a specification.

This invention relates to certain improvements in embroidering machines and more particularly to mechanism for counterbalancing the weight of the tambour frame of the type in which the tambour frame is supported by a parallel motion mechanism, comprising a plurality of connected pivoted elbow levers provided with compensating spring mechanism for counterbalancing the weight of the frame.

The present invention relates to that class of compensating mechanism in which not only the varying forces of the counterbalancing springs, as they are expanded or contracted during the movements of the tambour frame, are automatically compensated, but in which the varying load moment due to the Varying leverage of the weight of the tambour frame about the pivots of the supporting elbow levers is also automatically compensated by meanscf a rocking mem er having a correspondingly curved surface and a flexible member having rolling contact with the curved surface.

According to the present invention the rocking member is constructed in the form of a cam which rotates in unison with a cylindrical member, the cam being connected to the counter-balancing spring by a flexible member which makes rolling contact with the cam, while the cylindrical member is connected to one arm of one of the elbow levers constituting the parallel motion mechanism by a second flexible member which makes rolling contact with the cylindrical member.

in order that the intention may be more clearly understood reference is made to the accompanying drawing illustrating the preferred construction of my improved counter balancing mechanism in elevation as applied to the tambour frame of an embroidering machine.

in the drawing 1 indicates the usual movable tambour frame of an embroidering machine which rests on the system of levers, two of which are shown on the drawing,

Patented Dec. 15, 1914.

Serial No. 796,305.

these levers constituting the usual parallel motion mechanism. Pivotally mounted at 3 on brackets 3 are elbow levers 1, i, the arms a carrying rollers 3 which support the tambour frame, while the arms l are connected by means of a wire 6. Secured at one end to a stationary support 7 is a counterbalancing spring 8, the free end of which is connccted to a flexible metal band 9 which makes rolling contact with the curved surface of a rocking member or cam 10 rotatably mounted on a shaft 11 carried in suitable bearings 12. lhe flexible member passes around the curved surface of the cam 10 and is secured thereto at 13. It will thus be seen that the tendency of the spring 8 is torotate the am 10 in anti-clockwise direction. Rotating in unison with the cam 10 is a cylindrical member or roller 1-1 likewise mounted on the shaft 11, and connected to the cylindrical member at the point 15 is a flexible metal band 16 connected to an adjusting element 17 adjustably mounted in the end of the arm i of one of the elbow lovers. The weight of the tambour frame 1 will thus tend to rotate the cylindrical member 1i and cam 10 in clockwise direction, this tendency being equalized by the retracting force of the spring 8 so that the tambour frame 1 is supported by the action of the spring 8.

1f the tamhour frame is moved upwardly or downwardly from the position shown on the drawing during the usual operations of the cmbroidering machine, the arms a of the elbow lovers will follow the movement of the tambour frame and the cam 10 will be correspondingly rotat 2d, while the leverage of the spring 8 about the shaft 11 will vary according to the position of the cam 10, thus compensating for the variations in the retracting force of the spring 8.

Since the leverage of the weight of the tambour frame 1 about the axis 3 of the elbow levers varies according to the position the tainbour frame, it is necessary to construct the curved surface of the cam 10 in such a manner as to also compensate for this variation. For this purpose the required curvature of the cam may be determined either mathematically or empirically.

I claim z- 1. In an embroidering machine having a movable tambour frame, a counterbalancing mechanism therefor comprising a plurality of elboW levers, one arm of each lever supporting said frame and the other arms of said levers being connected together, a rotatable cylindrical member, a flexible member connecting one of the connected arms of said levers to said cylindrical member and adapted to make rolling contact With the latter, a rocking member rotating in unison With said cylindrical member and having a curved surface, a counterbalanoing spring fixed at one end and a flexible member connecting the free end of said spring with said rocking member and adapted to make rolling contact With the curved surface thereof, the form of said curved surface being such that both the varying load moment of the frame and the varying forces of the spring are compensated.

2. In an embroidering machine having a movable tambour frame, a counterbalancing mechanism therefor comprising a plurality of elbow levers, one arm of each lever supporting said tambour frame and the other arms of said levers being connected together, a rotatable roller, a flexible band connected at one end to and passed around'said roller and connected at its other end to one arm of.

the connected arms of said levers, a rocking .member rotating in unison with said roller and having a curved surface, a counterbalancing spring fixed at one end and a flexible member connecting the free end of said springvvith said rocking member and adaptedto make rolling contact With the curved surface thereof, the form of said curved surface being su h that both the varying load moment of the frame andthe varying forces of the spring are compensated.

3. In an embroidering machine having a movable tambour frame, a counterbalancing mechanism therefor comprising a plurality of elbow levers, one arm of each lever supporting said frame and the other arms of said levers being connected together, a rotatable cylindrical member, a flexible member connecting one of the connected arms of said levers to said cylindrical member and adapted to make rolling conta t with the latter, a curved cam rotating in unison With said cylindrical member, a counterbalancing spring fixed at one end and a flexible band connected at one end to the free end of said spring and passed at its other end around said curved cam and secured thereto, the form of said curved surface being such that both the varying load moment of the frame and the varying forces of the spring are compensated.

In testimony whereof I have affixed my signature in presence of two Witnesses.

JOHANN JACOB KNEOHT.

' Witnesses:

Ennns'r J. lilAenN, Hans MnIoKn.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, .Washington, 1?. G.