Circular knitting machine and a method for moving the needles of a circular knitting machine

Patent metadata

Field	Value
Publication number	US-11225736-B2
Application number	US-201816607987-A
Country	US
Kind code	B2
Filing date	Mar 27, 2018
Priority date	Apr 24, 2017
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

A circular knitting machine includes a needle-holding cylinder having plurality of longitudinal grooves arranged around central axis, and plurality of needles, each being housed in longitudinal groove. Drive chain for each needle is inserted into each groove and operatively placed between needle and actuating cams. Drive chain includes sub-needle slidingly arranged in groove and having a butt. Butt is radially movable between operating position, extracted to engage with respective first paths and cause activation of needle and stitch formation, and non-operating position, retracted so as not to engage with first paths. A selector is arranged under sub-needle, and punch is arranged between sub-needle and selector. An activating element is slidingly arranged in groove between sub-needle and selector, can be longitudinally moved with respect to punch and sub-needle, and can be operatively engaged with sub-needle to switch butt of sub-needle into and retain it in operating position.

First claim

The invention claimed is:

1. A circular knitting machine, comprising:
a needle-holding cylinder having a plurality of longitudinal grooves arranged around a central axis of the needle-holding cylinder;
a plurality of needles, each being housed in a respective longitudinal groove;
actuating cams arranged around the needle-holding cylinder and movable with respect to said needle-holding cylinder around the central axis for causing or allowing movement of the needles along the longitudinal grooves so as to enable stitch formation by said needles;
a drive chain for each needle inserted into the respective longitudinal groove, located below the needle and operatively placed between the needle and said actuating cams;

wherein said drive chain comprises:
a sub-needle slidingly arranged in the respective longitudinal groove below the needle and having a butt, wherein the butt is radially movable between an operating position, in which it is extracted so as to engage with respective first paths defined by first actuating cams and cause activation of the needle and stitch formation by the needle, and a non-operating position, in which it is retracted so as not to engage with said first paths;
a selector at least partly slidingly arranged in the respective longitudinal groove below the sub-needle, having at least one respective butt radially movable between an operating position, in which it is extracted so as to engage with respective second paths defined by second actuating cams, and a non-operating position, in which it is retracted so as not to engage with said second paths;
at least one selecting device acting under control upon said selector for switching the latter into or retaining it in the operating position or the non-operating position;
a punch slidingly arranged in the respective longitudinal groove between the sub-needle and the selector, wherein a lower portion of the punch is engaged with the selector and an upper portion of the punch is engaged with the sub-needle, wherein the punch has a respective butt which can be engaged with respective third paths defined by third actuating cams;
wherein the drive chain comprises an activating element slidingly arranged in the respective longitudinal groove between the sub-needle and the selector, wherein the activating element can be longitudinally moved with respect to the punch and with respect to the sub-needle and can be operatively engaged with the sub-needle so as to switch the butt of the sub-needle into and retain it in the respective operating position.

2. The machine according to claim 1 , wherein the sub-needle comprises a supporting portion carrying the respective butt, wherein said supporting portion is elastically movable between a first configuration, corresponding to the operating position of the butt, and a second configuration, corresponding to the non-operating position of the butt.

3. The machine according to claim 2 , wherein the supporting portion is configured to exert an elastic restoring force upon the butt in the non-operating position of said butt.

4. The machine according to claim 2 , wherein the supporting portion comprises an elastically flexible arm extending and projecting towards the activating element.

5. The machine according to claim 1 , wherein the punch extends at least partly parallel and in a radially more inner position with respect to the activating element and to the sub-needle.

6. The machine according to claim 5 ,
wherein the sub-needle comprises a supporting portion carrying the respective butt, wherein said supporting portion is elastically movable between a first configuration, corresponding to the operating position of the butt, and a second configuration, corresponding to the non-operating position of the butt, and
wherein in the second configuration of the supporting portion, said supporting portion rests radially and at least partially against the punch.

7. The machine according to claim 2 , wherein the activating element has an upper end with an inclined surface, wherein said inclined surface cooperates with a lower portion of the supporting portion, so as to switch the butt of the sub-needle into the respective operating position against the elastic force exerted by the supporting portion.

8. The machine according to claim 2 , wherein the activating element has a seat located at said upper end and counter-shaped to the lower portion of the supporting portion, so as to receive at least part of said lower portion and retain the butt of the sub-needle in the respective operating position and/or to axially push against the ssub-needle.

9. The machine according to claim 1 , wherein the activating element has a lower end which can be engaged against an abutting surface of the punch by means of a single-side axial rest.

10. The machine according to claim 1 , wherein a lower end of the punch can be engaged against an abutting surface of the selector by means of a single-side axial rest.

11. The machine according to claim 1 , wherein an upper end of the punch can be engaged against an abutting surface of the sub-needle by means of a single-side axial rest.

12. The machine according to claim 1 , wherein the activating element has a respective butt which can be engaged with respective fourth paths defined by fourth actuating cams.

13. The machine according to claim 1 , wherein the sub-needle has an auxiliary butt which can be engaged with respective fifth paths defined by fifth actuating cams.

14. The machine according to claim 1 , wherein the selector has an auxiliary butt which can be engaged with respective sixth paths defined by sixth actuating cams.

15. The machine according to claim 1 , wherein the selector comprises: an axially moving element slidingly arranged in the respective longitudinal groove and having said respective butt and auxiliary butt; an axially stationary element; wherein the axially stationary element is oscillating by effect of the selecting device and is operatively engaged to the axially moving element so as to radially move at least the respective butt between the operating and non-operating position.

16. The machine according to claim 1 , wherein the drive chain is configured for decoupling an axial movement of the activating element from an axial movement of the punch.

17. A method for moving the needles of a circular knitting machine, wherein said machine is made in accordance with claim 1 , comprising the steps of:
radially moving a butt of a sub-needle engaged with a respective needle, between an operating position, in which it is extracted so as to engage with respective first paths defined by first actuating cams and cause the activation of the needle and the stitch formation, and a non-operating position, in which it is retracted so as not to engage with said first paths;
wherein the radial movement of the butt of the sub-needle is caused by a relative axial movement between the sub-needle and the activating element axially located below the sub-needle;
wherein said relative axial movement is, at least in some steps, disconnected/independent from an axial movement of a punch and/or of a selector arranged under the needle and operatively activated by a selecting device acting under control upon said selector.

18. The method according to claim 17 , wherein in said step of radially moving the butt of the sub-needle, said butt is switched into and retained in said operating position during needle descent.

19. The method according to claim 17 , wherein a basically radial elastic force acts upon a supporting

Assignees

• Santoni & C Spa

Inventors

• Lonati Andrea
• Alghisi Mauro
• Lodrini Maurizio

Classifications

• D04B15/78

  Electrical devices · CPC title

• D04B15/322

  in circular knitting machines with needle cylinder and dial (cam systems specially provided for dials D04B15/34) · CPC title

• D04B9/38

  with stitch patterns · CPC title

• D04B15/68 Primary

  characterised by the knitting instruments used · CPC title

• D04B9/36 Primary

  Intarsia work obtained by reciprocatory action · CPC title