US2340049A - Cam for knitting machines - Google Patents

Description

O. FREGEOLLE Filed May 13, 1945 CAM FOR KNITTING MACHINES Jan. 25; 1944.

F I G. 3.

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15 dwwmiiezceazzg Patent ed 18.11.25, i944 UNITED STATES PATENT OFFICE CAM FOR KNITTING MACHINES Oscar Fregeolle, Central Falls, R. I., assignor to Hemphill Company, CentralFalls, R. 1., a. corporation of Massachusetts Application May 13, 1943, Serial No. 486,802

2 Claims.

This case deals with a safety cam construction for knitting machines such as circular, independent needle knitting machines. dles, jacks or other instrumentalities in machines of the type concerned, the selecting movement is frequently divided into two parts, one of which merely moves the instrumentalities from a position in which they would not contact a cam for imparting the secondary movement to a position in which they will contact that cam, and the second part of the movement, one in which the instrumentalities which have been primarily selected are moved throughout a considerable extent to perform their intended function.

In machines such as Banner type hosiery machines the instrumentalities to be selected frequently have a pluralityof removable selective butts and a master butt. The selective butts are broken away according to pattern requirements and those selective butts which are'left intact are engaged by one or more selecting instruments or plungers. These selecting instruments or plungers are moved to and from an active butt :ngaging position according to a predetermined pattern.

The second movement imparted to instrumentalities of this type is preferably by means of a socalled master cam engagable with the master butt. Each of the instrumentalities will have one of said master butts and the construction is such that as a preliminary selective movement is imparted, the master butt will be so positioned as to engage and be moved by the master cam. Otherwise, under normal operation, the master butt will pass the master cam without engagement.

Upon changing the position of the selecting means or plungers engageable with the selective butts, it is frequently unavoidable that one of these plungers will be removed at such a time as to leave a selected instrumentality in a position somewhere between its non-selected and a completely selected position as the latter would be determined after passing the primary selecting mechanism. Such a condition gives rise to in-- terference between the master butt and the master cam. If the master cam is solidly mounted, the butt will be broken upon engagement with the ,point of the cam, however, to avoid that, the

master cam is customarily retained in position by spring means and is to move out on improper engagement with any of the master butts. The spring for maintaining the master cam in position must be fairly strong to avoid unintended cam movement, but if it has too much tension, butts In selecting neemay be broken rather than the cam moving out as intended.

To avoid the above mentioned difliculties, the applicant has devised a safety cam functioning between the primary and the secondary selecting stages, this safety c'am being very easily moved upon engagement by one of the master butts and functioning to return those instruments the butts of which are left in a half-way position by the primary selecting movement to a position in which they will safely pass beneath the master cam. Thus this,safety cam has the advantage of providing a very easy movement which cannot result inbreaking butts, also assures that partially selected instruments will be returned to a non-selected position.

.In the figures of drawing:

' Fig. 1 is a diagrammatic view, certain parts being shown in section, illustrating a typical selecting means for needle jacks to which the safety cam has been applied;

Fig. 2 is a section taken through the needle cylinder and cam mechanism showing a jack butt passing below the safety cam;

Fig. 3 is a section similar to Fig. 2, but showing the manner in which a completely selected jack is elevated so that its -master butt passes above the safety cam;

Fig.5 is similar to Figs. 2 and 3 showing master butts being drawn down by the safety cam.

The invention is illustrated by showing as a .typical example a simple selecting 'means for needle jacks. It is to be understood that it applies to control of any type of knitting instrumentality so long as that instrumentality has a selective movement imparted thereto and at a certain point in that selective movement,

a change is made whereby the selected instrumentality may be left in an intermediate position. The cam applies to each individual selecting means, and if there are more than a single selection of the instrumentalities for each complete cycle, then as many safety cams as are necessary are provided.

Now referring to Fig. 1, a jack I has a plurality of selecting butts 2 and. a master butt 3. That ,jack alsohas a butt 4 by means of which it is any desired manner preferably by being broken away asis now the common practice. For each of the butts 2 there is provided a selecting plunger and these plungers are maintained in proper alignment to be engaged by their respective selective butts in the event the plunger is-in active position and one of the butts 2 is left on the jack at that position. 2' When selected by one of these plungers, the 'path travelled by one of the butts 2 indicated at line 5 changes to a slightly higher elevation as' shown by line 1. The master butt 3 follows a parallel pathway first at line 8 and then at line 9.

Master cam is so positioned and constructed that the master butts 3 only may contact it and if those buttsmove in line 8, they pass beneath the cam, that is, do not have any selecting movement whatsoever. If a jack is primarily selected by one of the plungers 5 so that the master butt then moves along line 9, that master butt will be raised by cam Hi to the elevation at line H. The cam i2 is the usual raise cam and that levels the master butts prior to approaching the selecting plungers.

If in withdrawing one of the plungers 5 at a time when one of the butts 2 has travelled only part way along that plunger, or for any other reason, a master butt 3 will approach the point of cam H1 at an elevation somewhere between lines 8 and 9 so that it would neither travel below nor would it ride up the cam as intended, the safety cam presently to be described functions to move that butt and the jack to a position so that the butt will pass beneath cam Ill. The safety cam is constructed as illustrated and has a cam portion l3 projecting inwardly at the upper end of a body portion l4 pivoted to swing about the pin IS. The pin I5 passes through a plate l6 and into the raise cam I2. A sort of groove or slot is formed in the raise cam and the body portion 14 of the safety cam is so designed that as shown in Fig. 1, the groove acts as a stop preventing movement of the cam toward the plungers 5 and in the other direction as shown in Fig. 4, prevents movement oppositely or in the direction of cam I0. A spring II'attaches at a fixed point and to the upper end of the safety cam maintaining it in the position of Fig. 1 except as contacted by one of the butts 3 at which time it swings to the position of Fig. 4.

The cam portion I3 is bevelled at about the same angle as the top of a butt 3 and is also bevelled at the forward edge and at its rear part so as to guide butts downwardly beneath the cam no matter whatthe direction of approach of passing jacks and their butts.

butts pass at one time, the first will swing the cam i3 to the position of Fig. 4 and it will remain in that attitude until all of those butts have the butts 4 and will lower jacks which have been The pivot l5 isto the right of the cam part i3,

Figs. 1 and 4, and that causes the cam l3 when engaged by "one of the butts 3 to swing to the position of Fig.4 and thereby to rise and to assume an inclined attitude. is in such a position that a butt 3 riding along the raise cam and whose jack-is-not aifected by anyone of the plungers 5 will pass beneath cam I3, Big. 2'. Selected jacks. will be elevated to such an extent that their butts 3 will move above the cam i3, see line 9 and Fi 3. H

When contacted by a butt moving at an intermediate position, the cam will be swung to the right,1,Fig. 4, thereby elevatingv the front edge of thecam above the top'of the butt whereupon that: butt will then beJoWered sufliciently so that it must pass beneath cam-ill. Such action is illustrated in Fig. 5 and the path one of the butts 3 wotild thus follow is showfiii Fig; '4. If several '60 Normally cam 13 primarily selected, but which are not to complete that selecting movement. This cam functions in advance of cam l3 so that all butts 3 on jacks having one'of the butts 4 and while cam 18 is active, will pass beneath cam 13. I

For reciprocatory work the cam I3 is so beveled that butts passing in reverse strokes are guided beneath the cam and thus there is no improper functioning or interference atthat time.

The invention has been described by reference to one specific embodiment ofthe' same, but it is to be understood that many variations may be resorted to without departing from the scope of the invention as originally conceived. The ap plication to 'jacks of the type-shown is merely instrumentalities "are I f equally well controlled, also the selecting butts" themselves may be of other shape, for example,

illustrative and other may be square or rectangular in shape rather than of saw-tooth construction. Circular ma chines are only one type of knitting machine to which the invention applies and it may equally well be used in straight machines or in any other type machines where instrumentalities are selected and the instrumentalities and cams have relative movement. The invention islimited only by the scope of the appended claims.

I claim:

1. In a knitting machine, the combination of instrumentalities having selecting butts and a master butt, selecting means for said first mentioned butts and a fixed master cam engageable with said master butts, a safety cam positioned between said selecting means andsaid master cam and having a cam surface sloping downwardly toward said master cam, said safety cam also being pivoted so "that its cam surface can swing upwardlyand toward said master cam in order that any master-butts positioned so as to instrumentalities having selecting butts and a master butt, a plurality oftselecting plungers. operable on selecting butts and a master. cam" engageable with the master butts, the construction being such that the withdrawaiof a plunger may leave one or morelof the master butts in such position as. to contact improperly witlrthe master cam, a safety cam between said plungers and master cam pivotedto swing in the .,direc-. tion of said masterca'm upon-contact ,withany,

of said improperly positioned butta said safety cam also havinga downwardly slopingtcam sur- I face adapted to, rise when its end is engagedby'a butt untiT said butt m'oves from contactwith said end onto. said cam surface whereby; it,' is, ;gi 1i"' ed to a position in which itwi ipassfu ea master SCAR,

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