US2177054A

US2177054A - Apparatus for spiral binding

Info

Publication number: US2177054A
Application number: US720152A
Authority: US
Inventors: Catini Vincenzo
Original assignee: Individual
Current assignee: Individual
Priority date: 1934-04-11
Filing date: 1934-04-11
Publication date: 1939-10-24
Anticipated expiration: 1956-10-24

Description

Oct. .24, 1939. v. mm" 2,117,054

APPARATUS FOR SPIRAL BINDING Filed April 11, 1934 2 Sheets-Sheet l L ATTORNEY Tifi.2.

III! Ill 53 Ill 52 fllgl lllllllllgl li 9 illil 3 V. CATINI APPARATUS FOR SPIRAL BINDING Filed lfiril 11, 1934 2 Sheets-Sheet 2 I 1 HO I04.

INVENTOR I z'zzcenzo Calzzzz Patented Oct. 24, 1939 UNITED STATES i' ATENT OFFICE APPARATUS FOR SPIRAL BINDING Application April 11, 1934, Serial No. 720,152

. 12 Claims.

My invention is concerned with theart of binding together sheet material assembled in stacks, by means of a spiral binding element threaded through holes in the stack. One of its general 5,. objects is the provision of apparatus for binding whereby the coils of a spiral binding element may be accurately aligned with the perforations preformed in a stack of sheets to be bound.

Among other objects in relation thereto are the provision of means for rectifying any inaccuracies in the pitch of the coils of the spiral binding element, which will insure proper alignment of the coils with the perforations in the stack, the provision of means for accurately positioning a perforated stack of sheets in relation to a spiral element to be threaded through the perforations thereof, the provision of means for threading one end of a long spiral into the perforations of a stack of sheets and of stopping go; said threading operation when the spiral has advanced the desired amount and the provision of means for conveniently severing a section of the spiral of predetermined length from the main body of the spiral, while said section of spiral is 25- in assembled relation with a stack of sheets without removing the stack from the machine on which the threading operation has been performed.

For the attainment of these objects and such 30. other objects as will hereinafter appear or be pointed out, I have shown one embodiment of my invention in the drawings, wherein:

Figure 1 is a plan View of a machine for carrying out my process of binding with parts there- 35. of shown diagrammatically; and portions thereof being broken away to expose underlying portions;

Figure 2 is a side elevation thereof;

Figure 3 is an end View thereof, with portions 40 broken away, and corresponding to the line 3-3 of Figure 2 and looking in the direction of the arrows;

Figure 4 is a section on the line 4-4 of Figure 2 looking in the direction of the arrows; and

45 Figure 5 is a section on the line 5-5 of Figure 1 looking in the direction of the arrows.

In general my method of spiral binding may be described as one in which a spiral binding element is rotated about its axis and caused to ad- 50' Vance axially at the same time, while a stack to be bound is held stationary and in such a position that a row of perforations therein is in line with the path of the coils of the advancing spiral so that the advancing end of. the spiral 55 will thread through the perforations, one after the other, and, in the ideal case, without contact with the walls of the perforations, While each succeeding element of the spiral will follow the same path as the end thereof.

However, in carrying out the operation of in- 5 serting a spiral binding element into a stack of sheets having perforations preformed therein, it is frequently found that the pitch of the spiral does not correspond accurately to the pitch of the perforations, and even though the average pitch of the coils of the spiral does correspond to the pitch of the perforations, there may be such variations of individual coils of the spiral from the normal or average pitch as will interfere with the smoothness and efficiency of the thread- 15 ing operation. As one of the features of my invention I therefore provide means for rectifying the coils of the spiral so as to make the pitch of all the coils thereof substantially uniform and equal to a predetermined pitch, which,of course, will be that of the stack to be bound. In the embodiment disclosed herein I not merely show such rectifying means, but I show the rectification as one of the functions of elements intended at the same time to guide and to advance the spiral. It is to be understood, however, that this is not necessarily so, as separate elements for carrying out these functions separately may be provided. Associated with such guiding, advancing and rectifying means is means for positioning the stack to be bound, whereby its positional relation to the guided and rectified spiral may be determined, so as to secure accurate alignment of the coils of the spiral and the perforations in the stack.

In carrying out my process on the machine herein disclosed, the operator takes a spiral of any convenient length, preformed by separate apparatus or by auxiliary apparatus, appended to the machine and inserts the same into the portion of the machine intended to receive the spiral. The operator then positions a stack of sheets in the machine in the proper relation to the path of the spiral, and starts the rotation of the spiral which is thereby caused to advance in the proper path until it reaches a predetermined point, at which point an automatic control stops the operation of the machine and the further advance of the coil. At this 'pointa cutting device also located at a predetermined point, and so as to determine the proper length of the binding element, is caused to sever a section of the spiral from the main body. The bound stack is then removed from the machine and a new stack inserted into the machine, and the cycle is repeated until the length of spiral is used up.. At that point it is necessary to insert a fresh length of spiral into the machine before the operation can be continued.

Having thus outlined the steps involved in carrying out my process, I will now describe in detail a machine such as I have found to be adapted to carry out my process in an efficient manner.

Such a machine, as shown in the drawings, comprises first of all mechanism for actuating the spiral so as to advance it and thread it through the perforations in the stack to be bound and this advancing means at the same time performs the function of guiding the spiral and of rectifying the pitch of the coils thereof, so that they will register accurately with the perforations in the stack of sheets, positioned in means to receive and hold same, and my machine further comprises stop means that will automatically stop the functioning of the advancing means so as to stop the advance of I the spiral, and means to sever a section of the spiral of suitable length from the main body thereof, this section being of a suitable length desired, and forming the binding element for the stack. The means for holding the stack of sheets in the proper relation to the ad vancing spiral mentioned hereinabove, may further be arranged for properly forming the stack in such a manner that the tubular openings formed by the aligning perforations of the superposed sheets, will be arcuately shaped and thereby more accurately register with the coils of the 7 spiral by conforming to the curvature thereof.

The guiding, advancing and rectifying means is shown as comprising a system of three elongated rotatable cylindrical members, the lowermost one of which, designated by the numeral 9 is positioned in fixedrelation to the bed of the machine, while the other two, designated by numerals ID, are adjustably. positioned in relation to member 9. Each of the members 9 and I9 is provided with annular grooves I2, uniformly spaced from each other a distance equal to the pitch of the spiral, or of the perforations in the stack to be bound by the spiral, which, of course, ideally should be identical with the said pitch. By referring to Figure 4,.it will be seen that the members 9 and I9 are therein shown as arranged in a triangular relation so as to surround the spiral and to receive the coils thereof within their grooves I2, and for this purpose each of the members 9 and III has its grooves I2 longitudinally displaced in relation to the grooves of the other members 9 and II). The necessity for this will be obvious from a consideration of the fact that the grooves at their points of contact with the spiral must be aligned with the coils thereof.

To accomplish rotation of the members!) and I9, each one is shown as connected'bya flexible shaft I4 with a pinion I6 driven by a central driving gear I8, this gear system being journaled in a standard I! mounted on the bed 8 of the machine. As the members are caused to rotate about their axes their grooves I2 frictionally engage the spiral 39 and cause it to rotate and to advance, the action resembling that of a screw and nut. The member 9 is journalled at its respective ends in bearings 29 carried by standards 22 mounted on the base or frame of the machine and members ID are journalled at their ends .in bearings 23 provided in members 24 pivotally and adjustably carried at each end of members III, as shown at I9, by a block 29, adjustably .carried by the standard 22. This adjustable construction provides for vertical adjustment of the block 26 and comprises a vertical slot .28 in standard 22, and a screw 29 passing therethrough and threaded into the block 26, whereby the block and the standard may be clamped together in any desired position of ad justment.

The purpose of this adjustable construction just described will be obvious from an inspection of Figure 4, which is a cross section of the machine and in which the spiral element, designated by numeral 39,'is shown in contact with the grooves I2 of members 9 and I9 and as being threaded through the perforations 32 of a stack of sheets 34. It will be evident that if it is desired to use a spiral of larger diameter than shown, at least one of the elements 9 or It] must be shifted andfor purposes of symmetry I have shown the two members I9 laterally and vertically shiftable, as just described.

A further element of adjustability is introduced by the provision of an assortment of elements 9 and II] of various diameters which may be selectively'used to provide for various conditions and contingencies. For instance, the diameters of the members 9 and I9 may be selected and their positions adjusted so that when they are in proper position to guide the spiral 39 the distance between the two adjustable members I9 will be just sufiicient to receive the stack placed between said members. In other words, adjustment of this feature of the machine depends for proper operation upon twovariable factors; (1) the spacing of the members 9 and I9, which must be sufficient to'accommodate the spiral 39 and (2) their diameter, which must be such that a space great enough to receive the stack is provided. It will at once be apparentthat by providing for their variability of' diameter in conjunction with adjustability of position the members I9 may perform a function not heretofore mentioned. Their diameter may be so selected that they serve to hold the sheets of the 'stack together during the threading operation.

In other words, the space between them may be made just sufficient and no more, to accommodate the stack. Such is the relation shown in Figure 4.

It is to be noted that if the rotational speeds of the guide members 9 and II! are the same, their diameters should ordinarily be the same since that would be necessary to prevent slipping of the coil in relation to the members 9 and II]. However, for certain purposes different diameters and speeds may be found of advantage, and these may be relatively determined to produce the result desired.

The members 24 carrying bearings 23 were previously stated to be adjustable and this appears from Figure 3 in which the construction is shown as comprising for each member 24 a bracket 36 carried by block 29 and serving as a support for the free end of a. resiliently compressible member indicated as a whole by numeral 31 and comprising a rod 39 carrying a piston 39 at one end and threaded at its other and outer end, as shown at 49, and adapted to be held in various positions of adjustment in relation to the bracket 36, for whichpurpose the threaded end 49 may engage a threaded opening in the bracket 36. In addition a pair of nuts 4| are provided, and these will assure permanency of adjustment by serving to prevent accidental dis placements.

The member 31 further comprises a cylinder 42,

through the head 43 of which passes the rod 38 and within which is located a resilient compression I element, such as compression spring 45, which will act to force the piston 39 against the cylinder head 43. The cylinder 42 is pivotally connected at its end to a member 24, as indicated at 44. It will be understood that as a result While cylinders 42 are confined to rectilinear mo,-

tion because of the fixed position of rods 38, it will be obvious that the pivots 44 may be made sufiiciently loose or the fit between the walls of cylinder 42 and the piston 39 may be sufliciently free to allow for the limited extent of the arcuate movement. Finally either the brackets 36 may be pivotally mounted or an assortment of brackets 36 may be provided, each for use under certain conditions.

It will further be seen upon an inspection of Figure 4 that in order to bring a stack of sheets 34 into the proper relation to the coils of the advancing spiral 38, it is necessary that it be positioned properly as to vertical height and for this purpose brackets or stop members 50 may be provided at a plurality of points, two being indicated in Figure 2, although it is obvious that more may be employed, if desired. These stop members 59 are made in the form of U- shaped brackets having slots 58 in their free ends 52, whereby they may be held in adjustable relation to standards 54 mounted on the bed of the machine, by screws 55 passing through the said slots 58. By making the top of bracket 55 arcuate in shape the back of the stack 32 may bev arcuately formed thereby, and the perforations 34 therein may be arcuately arranged, as shown in Figure 4. As a result the perforations may be more accurately aligned with the spiral, and smaller perforations may be used than where they are aligned so as to form a straight-walled tube.

The members 9 and I!) may be driven by any suitable form of motive. power, but when automatic stopping mechanism to stop the advance of the spiral at a predetermined point is used, I have found that an electric motor is very convenient for this purpose because of its adaptability for ready control, and in the embodiment herein described, I have shown such an electric drive and also shown an electrical stop mechanism. It will be understood, however, that I do not necessarily limit myself to such electric drive and electric stopmechanism, as other forms of energy may also be utilized.

An electric motor is indicated at 60, and it is shown as driving the pinion I8 through a coupling 62 of any preferred form. The motor is energized from anelectric power line 64, and its circuit may be broken by a switch 66, which is made automatic in operation by a solenoid 68. This solenoid may be connected directly across the power line or may be in series with the motor 60, as shown, in which event it will function more orless as a starting resistance for the motor, and is adapted to have its circuit interrupted automatically for the purpose of opening the switch and stopping the motor, as will hereinafter be described. When the solenoid 68 is energized, the armature 10 will meet contact 12 and thereby close the motor circuit and start the motor, but when the coil is deenergized, or in the position shown in Figure 1, the armature Ill and contact 12 are separated, and the motor circuit is open. For automatic closing of the circuit of solenoid 68, I may employ a relay 14 having a coil 19 adapted to be energized by a source of low voltage current, such as the battery 78, and in the circuit of coil 16 is a circuit closing device of any suitable or preferred type adapted for ready and convenient manual operation, such as the push button 80. The armature 82 of the relay, when attracted by the coil thereof, is adapted to meet a stationary contact 86 and thereby to close the circuit comprising the coil 68 of the switch 56 and to start the motor. On closing the circuit of coil 16 by means of the push button 89, therefore, the circuit of coil 58 is closed and the motor is caused to start and thereby to advance the spiral 39.

The automatic stop mechanism, whereby the advance of the rotating spiral 38 will be stopped at a predetermined point, comprises a circuit for short circuiting the battery 18. When this occurs the coil 76 will be deenergized sufiiciently, due to the drop in battery potential, so that the armature 82 is released, thereby opening the cirsuit of coil 68 and throwing the switch 66 into its open position, which of course causes the motor 69 to stop. This short circuiting arrangement for the battery 18 comprises a circuit which includes the spiral binding element and the bed 8 of the machine. The spiral binding element is in electrical conducting relation to the members 9 and I0 and the bed 8 of the machine and thereby, through the terminal 81 on the bed 8 of the machine, is connected to one pole of the battery '58, while a second terminal 88 is insulated from the bed of the machine and the spiral 30 and is connected to the other pole of the battery 18. A stop member 90, itself an electrical conductor, is in electrical conducting relation to the terminal 88, and is introduced in the path of the advancing spiral. From the preceding description, it will be seen that as the spiral 30, in its advance by and along the guides 9 and I0, strikes the stop 99, the circuit comprising the spiral, the members 9 and iii, the bed of the ma chine and the battery 18, will be short circuited, and the motor will be stopped as hereinabove described.

The stop 99 may be formed so that while it performs its electrical function it may also serve as a mechanical stop for one end of the stack, whereby its perforations will be aligned with the coils of the spiral, and the surface thereof which contacts with the stack may be inclined so as to bias the stack and the holes therein for better registration with the coils of the spiral.

For the purpose of severing from the main body of the spiral a section of a length suitable for serving as an individual binding element for the stack through which it has been threaded, a cutting arrangement in the form of shears, indicated as a whole by numeral 93, has been shown as adjustably mounted on the bed of the machine and having the point of operation thereof located in the path of the spiral 39, so as to cut through the same when rendered operative, as clearly appears from Figures 1 and 2. One of the blades of the shears is indicated at 94 as formed on a support 96 adjustably fastened to the bed of the machine, while the complementary blade 98 is formed on a movable member I90 which is pivoted to the support 96 as shown at I92. The mecha- ELS nism for moving the .member I00 comprises a slidable member I04 in pivotal relation to the member WI), as indicated at Hi6, which member slides within the supports I It and I2!) on the bed of the machine and carries fixed thereto a collar I69 having an inclined surface H2, thereon, and between the latter and support H9 a rotatable cam I I4 adapted for turning by the arm I I6 projecting therefrom. When the cam H4 is shifted by turning, it will be obvious that, if the parts are initially in the position of Figure 1, the member I04 will be pushed toward the left, and thereby the blade 94 of the shears will be caused to close against blade 98 and to sever the spiral. In order to cause an automatic return of the shear blades into their open position, a compression spring H8 is positioned between a collar I08 on the member It] and the support I29, this spring H3 being compressed when the member I94 moves the shear blades into open position. It will be further noted that the collars I88 and I09 are adjustably mounted on member I84 by set screws.

While the shear mechanism has been indicated foot operated through lever I22, it is to be understood that it may likewise be operated in any other suitable manner, such as by hand or automatically at a predetermined time, The particular manner of operation will, of course, be

1 dictated by convenience or the particular condition of operation. For the sake of simplicity however, I have illustrated a foot operated mechanism. I i L In order to permit of variation in the Wldbh of the stacks to be bound, which naturally requires a variation in the length of the binding element, both the contact and the shears are shown as adjustable in position on the bed of the machine, and axially in relation to the spiral. This has been outlined in the drawings, and in view of the frequency with which such adjustable supports are employed, it is believed unnecessary to describe the construction thereof in detail.

As added conveniences in the operation of the machine, I have shown a guide channel 3! for supporting the spiral 30 before it enters the space between the guide members 9 and III and a hook I24 serving to hold the spiral in place when the two cylinders Ill are separated, which necessarily occurs every time a completed bound stack is removed from the machine.

In the operation of my machine the operator first selects a length of spiral, placesit in the guide 3|, and then inserts one end thereof between the guide members 9 and II] and so that its coils engage the grooves I2 in said guide members. He then taken a stack of sheets 32 and inserts it between the uppermost guides Ill so that its back rests on the stop 59, the stop 50 having been previously selected with a view to the proper curvature so that the holes in the stack, formed by perforations 34, are suitably curved to receive the spiral, and also adjustedto the proper height so that the perforations 34 are vertically aligned with the uppermost sections of the coils of the spiral, and the members 9 and I0 having been selected with a view to the proper diameter, and having been properly adjusted in relation to the size of the stack and the size and location of the perforations thereof, the operator must further position the stack laterally, and for this purpose he places one end of the stack, that is the right hand end, if the machine is arranged as in Figure l, in proper relation to the stop 90, and so that the perforations 32 of the stack register with the grooves I2 of the guiding elements I0. Where the stop 90 is formed was to have the dual function of a stop for the stack and for the spiral, the operator need only be concerned with holding the stack against the stop 90.

The stack having been positioned, the operator may now press the button 8!], which starts the motor in operation, and causes rotation of the members 9 and II), thereby advancing the spiral 30, which causes it topass through the perforations in the stack, and this advance continues until the end of the spiral strikes the stop 90, when short circuiting of the battery 18 takes place, and consequently the solenoid I6 is deenergized and the switch 66' is opened, thereby stopping the motor and the advance of the spiral. The operator now releases the push button, thereby preventing the motor operation until the button is again pushed down, severs a length of spiral from the main body of the spiral by the cutting arrangement, and promptly removes the stack from between the guides 9 and I0, thereby breaking the short circuit and restoring the electric circuits to their normal condition in which they will be ready for the next cycle of operation.

While I have disclosed one embodiment of apparatus for binding, it will be obvious'to those skilled in the art that the same may be embodied in many other forms without departing from the spirit thereof, and that I do not limit myself in any way other than as defined in the appended claims.

Having thus described my invention and illustrated its use, what I claim as new and desire to secure by Letters Patent, is: I

1. In apparatus for threadinga spiral binding element into a stack of sheets having uniformly spaced perforationsalong one edge thereof, guiding means for said spiral, pitch rectifying means for said spiral, said guiding means being adapted to cause the advance of said spiral so as to thread the same through the perforations of said stack, adjustable means for positioning said stack so that its perforations lie in the path of said advancing spiral, and means for automatically stopping the advance of said spiral at a predetermined point in relation to the stack and means for automatically severing said spiral at a predetermined point in relation to the stack after the advance of said spiral is stopped.

2. In a machine for threading a spiral binding element into engagement with a stack of perforated sheets, a cylindrical element positioned in axial parallelism with said spiral so as to engage the sides of the coils thereof, supporting elements for said spiral adapted to hold said spiral in fI'lC'. tional engaging relation with said element, and means for rotating said cylindrical element, whereby said element will rotate said spiral and cause it to advance, and means for positioning the perforations of said stack in alignment with the path of the advancing spiral.

3. In a machine for threading a spiral binding element into engagement with a stack of perforated sheets, a cylindrical element having a plurality of annular grooves therein, said grooves being uniformly spaced from each other a distance equal to the pitch of the perforations in the stack, and in axial parallelism with said spiral so that the grooves therein engage the sides of the coils of the spiral, supporting elements for said spiral adapted to hold said spiral in frictional engaging relation with the grooves of said element, and means for rotating said cylindrical element, whereby said cylindrical element will rotate said spiral and cause it to advance, and means for positioning the perforations of said stack in alignment with the path of the advancing spiral.

4. In a machine for threading a spiral binding element into a stack of preforated sheets, guiding means for the spiral element comprising a plurality of cylinders mounted so as to be rotatable about parallel axes, said cylinders having annular grooves therein spaced apart a distance equal to the ideal pitch of the spiral binding element and being spaced apart so as to receive the coils of the spiral element within the grooves thereof, and in frictional engagement therewith, means for rotating at least one of said cylinders whereby said spiral element will be rotated, the direction of rotation of said rotating cylinders being such as to cause the spiral to advance in the desired direction, whereby the spiral will be caused to advance, and the coils thereof will be rectified to conform to the ideal pitch, and means for positioning the perforations of said stack in alignment with the path of the advancing spiral.

5. Apparatus as in claim 4, in which the cylinders are three in number, of the same diameter, and symmetrically arranged in relation to the spiral all of said cylinders being adapted to rotate at the same speed, and means for varying the positon of two of said cylinders in relation to the third, in order to accommodate spiral elements of different diameters between said cylinders.

6. In apparatus for threading a spiral binding element into a stack of. perforated sheets, in which the spiral binding element is caused to advance and during its advance in the machine is in conductive electrical contact with the bed thereof, a source of motive power for causing the advance of the spiral, stop means for stopping the advance of the spiral at a predetermined point, said stop means comprising a source of electrical energy of low voltage having one of its terminals in conductive relation to the bed of the machine and thereby to the spiral, and its other terminal insulated from the bed of the machine and positioned in the path of the advancing spiral, an auxiliary electrical circuit in multiple with the aforesaid circuit and comprising a manually operable circuit closing device and a solenoid, and means operated by said solenoid and adapted to start operation of the source of motive power when the solenoid is sufficiently energized from the low-voltage source by closing its circuit, and to stop the operation of the source of motive power when said low voltage circuit is short-circuited by contact of the spiral with said insulated terminal and the solenoid thereby deenergized.

7. Apparatus as defined in claim 6, in which the source of motive power is an electric motor, and the means to start its operation is a circuit opening and closing device adapted to connect the motor with an electric power line when said solenoid is energized sufficiently,

8. Apparatus as in claim 4, in which the cylinders are three in number, of the same diameter, and symmetrically arranged in relation to the spiral all of said cylinders being adapted to rotate at the same speed, and means for varying the position of two of said cylinders in relation to the third, in order to accommodate spiral elements of different diameters between said cylinders, means for positioning the perforations of said stack in alignment with the path of said spirals.

9. A device for threading a spiral binding element through the perforations of a stack of sheets to be bound, said device comprising means for causing the advance of the successive portions of a spiral binding element along a predetermined path and thereby positively causing the successive portions thereof to conform to a predetermined contour and means for positioning the perforations of the stack in threaded relation to the coils of the advancing spiral, said means for causing the advance of the successive portions of the spiral binding element comprising a pair of elements spaced so as to receive therebetween the stack to be bound and to hold the sheets of the stack against separation,

10. A device for threading a spiral binding element through the perforations of a stack of sheets to be bound, said device comprising means for causing the advance of the successive portions of a spiral binding element along a predetermined path and thereby positively causing the successive portions thereof to conform to a predetermined contour, means for positioning the perforations of the stack in threading relation to the coils of the advancing spiral, automatic means for stopping the advance of the spiral at a predetermined point, and means operated automatically after said spiral stops advancing, to sever a section of the spiral from the main body thereof at a predetermined point in relation to the end thereof.

11. A device for threading a spiral binding element through the perforations of a stack of sheets to be bound, said device comprising means for causing the advance of the successive portions of a spiral binding element along a predetermined path and thereby positively causing the successive portions thereof to conform to a predetermined contour and means for positioning the perforations of the stack in threading relation to the coils of the advancing spiral, said advancing means comprising a pair of elements spaced so as to receive therebetween the stack to be bound and to hold the sheets of the stack against separation, and said device also including automatic means for stopping the advance of the spiral at a predetermined point, and automatic means operative after the advance of the spiral is stopped to sever a section of the spiral from the main body thereof at a predetermined point.

12. In combination with apparatus for threading a spiral binding element into a stack of perforated sheets in which the binding element is caused to advance into threaded engagement with the stack by moving guide means, means for stopping the advance of said spiral, comprising means in the path of the end portion of the advancing spiral and adapted to be engaged thereby, and means for stopping the motion of the guide means and thereby stopping the advance of said spiral, said means being in such operative relation to said spiral engaging means that when the end portion of the spiral engages said spiral engaging means said motion stopping means will act to stop motion of the guide means and thereby the advance of the spiral, and said means being part of an electrical circuit adapted to be short-circuited when the spiral engages the same and thereby adapted to stop the rotation of said rotating means.

VINCENZO CATINI.