US3315643A

US3315643A - Writing implement mechanism

Info

Publication number: US3315643A
Application number: US307605A
Authority: US
Inventors: Rose R Eratico
Original assignee: Individual
Current assignee: Individual
Priority date: 1963-09-09
Filing date: 1963-09-09
Publication date: 1967-04-25
Anticipated expiration: 1984-04-25

Description

April 25, 1967 R. R. ERATICO WRITING IMPLEMENT MEGHANSM 2 Sheets-Sheet l Filed Sept. 9,

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April 25, 1967 R. R. ERATICO WRITING IMPLEMENT ME'cHANIsM 2 Sheets-Sheet 2v Filed Sept. 9, 1965 Ilfldiilzillrlflilllll/ ELM KAf'Lmu ATTORNEYS United States Patent O 3,315,643 WRITING IMPLEMENT MECHANISM Rose R. Eratico, 63 E. 9th sf., New York, N.Y. 10003 Fired sept. 9, 1963, ser. No. 307,605 7 claims. (ci. 1z0-42.03)

This invention relates to an improved mechanism for extending and retracting an implement in a casing.

While the invention will be described with particular illustrative reference to a retractable ballpoint pen, it will be apparent that the invention is applicable to other marking devices, and that in fact the mechanism can be used to extend and retract many other objects.

It is common practice to make ballpoint pens wherein the tube or refill containing the ink and the writing means is normally wholly retracted in a casing, with means provided to extend the tube or refill out of the casing for writing purposes. In -one common general type of mechanisms, a button or other device is pushed to propel or extend the tube, and a catch is released, for example, by pushing the button, to permit retraction of the tube by means of a spring. Vast quantities of writing tubes or refills, of generally standard size and shape, are manufactured for use with mechanisms of this type.

In another type of mechanism action, a rotary mernber such as a cap, is mounted upon the cap and may be turned to actuate mechanism to extend -or retract the tube, as the case may be. Such mechanisms have commonly required the use of a special refill tube, different in construction from the refill tube commonly sold for the pushbutton type mechanisms. Furthermore, such mechanisms using a rotary actuating member have required a relatively considerably number of parts.

One object of this invention is to provide a mechanism utilizing a rotary actuating member, but having a minimum number of parts, and suitable for use with the standard, widely sold 'refill tube, as well as with any other suitable device to be extended and retracted.

Another object of the invention is to provide a mechanism of the above described type utilizing inexpensive parts, and easily assembled.

Another object of the'invention is to provide an improved impeller of the above described type, having simple stop means limiting turning of the impeller between limit positions wherein the tube is respectively retracted and extended.

In accordance with preferred embodiments -of the invention, the mechanism comprises a hollow, tubular casing having a lower end opening, together with means within the casing receiving the tube or rell with the lower end of the tube extendable through the lower end opening and retractable into the casing. The tube receiving means maintain the tube skew to the casing axis with the upper end of the tube offset from the axis. For example, the bottom end opening may be located on the axis, and the upper end portion of the tube may extend through a bushing iixedly received within the bore of the casing, the bore of the bushing being offset from the casing axis.

Further in accordance with preferred embodiments of the invention, spring means couple the tube and the casing and normally maintain the tube in retracted position. An impeller is mounted within the casing above the tube so as to be rotatable about the axis and so as to be accessible externally of the casing for rotation of the impeller. The impeller has an axial motion drum cam shaped and positioned so that the spring maintains the upper end of the tube against the cam surface. The cam surface is shaped, for example, having a helical contour, so that turning of the impeller to one turned posi- 3,315,643 Patented Apr. 25, 1967 ice tion causes extension of the tube and to another turned position permits the spring to retract the tube.

In another embodiment of the invention, the marking tube extends axially but terminates below the bushing. A pin extends through the offset bushing bore, one end of the pin being engaged by the impeller and the other end of the pin engaging the upper tube end.

It will be apparent that the invention utilizes simple parts. The special bushing with offset bore may be readily fabricated. The impeller may be readily produced in a variety of means, such as on a screw machine, by forming wire or by rolling flat metal stock. The remaining parts are of substantially conventional'design.

Other objects and advantages of the invention will become apparent from the following description, in conjunction with the annexed drawing, in which preferred embodiments of the invention are disclosed.

In drawing,

FIG. l is a perspective view of a marking implement, illustratively a ballpoint pen, in accordance with this invention;

FIG. 2 is a longitudinal section on line 2-2 of FIG. 1, showing the point of the marking tube in retracted position in full lines and in extended position in broken lines;

FIG. 3 is a fragmentary view similar to FIG. 2, but showing the mechanism in tube-extending position;

FIG. 4 is a fragmentary side elevation, to enlarged scale, of one embodiment -of the impeller;

FIG. 5 is a view similar to FIG. 4, showing a second embodiment of the impeller;

FIG.6 is a View similar to FIG. 4, showing a third embodiment of the impeller;

FIG.7 is a developed View of the impeller of FIG. 6;

FIG. 8 is a View similar to FIG. 4, showing a fourth embodiment of the impeller;

FIG. 9 is a section on line 9 9 of FIG. 2;

FIG. 10 is a section on line 10-10 of FIG. 3;

FIG. 1l is a longitudinal section of another embodiment of the invention, wherein the marking tube shown retracted, extends axially and is engaged by a pin extending through the offset bushing bore against the impeller;

FIG. 12 corresponds to FIG. 10, although partly in elevation and shows the marking tube extended; and

FIG. 13 is an exploded perspective view of the pin and bushing.

FIGS. 1-10 Upon reference to the drawings in detail, it will be noted that it shows a writing implement 10, illustratively a ballpoint pen, comprising an elongated, hollow tubular casing 11 having open upper and lower ends. Casing 11 is preferably made in two parts, open-ended l-ower barrel 12 and upper cap 13. Barrell 12 and cap 13 are tubular and of the same outer diameter. The lower end of cap 13 has an open-ended extension 14 of reduced diameter, over which barrel 12 fits frictionally, with the upper end of barrel 12 in abutment with the lower end of the main part of cap 13, as clearly shown in the drawing. Alternatively, any other suitable means of interconnecting the two casing parts may be provided. The purpose of making casing 11 in two parts is to permit access to the interior for replacement of the marking tube. The lower end of barrel 12 is tapered at 12a, in the usual manner, to terminate in a reduced diameter lower end 12b having the circular lower barrel opening 15. The axis of opening 15 preferably coincides with the axis of casing 11.

Further in accordance with the invention, bushing 20 is fixed by frictional or other suitable means within cap 13, intermediate the ends thereof. Said bushing 20 has a through bore 21, the axis of which is .parallel to but offset from the main axis of cap 13. Replaceable tube 22, which may be a common ballpoint tube, extends slidably through bushing bore 21 and through casing 11, and is also adapted to extend slidably through opening 15. Specicaltly, the upper part of tube 22 may be cylindrical, with a portion of tube 22 flattened at 23 near the lower end of tube 22 to widen the tube at the flattened point. The open end of tube 22 receives a conventional tip 25, the lower end 24 of which is of reduced diameter. The lower end of tube 24 is tapered at 24a and may contain the ball (not shown) in the usual manner. For convenience, the entire refill is designated as tube 22, it being understood that the main portion of tube 22 is of diameter to extend freely through bore 21, and that the tube 24 is of diameter to extend freely through opening '15. It will further be apparent that since the lower end portion of tube 22 (portion 24) extends through the axial opening 15, and the upper end of tube 22 extends through the axially ottset bore 21, tube 22 is skew to the barrel axis with the upper end of tube 22 offset from the barrel axis.

Spring 26 couples tube 22 and casing 11 and -is adapted to maintain tube 2.2 normally in retracted position. Spring 26 is a coil spring with its lower turns 27 frictionally received within barrel 12 at the point at which the taper 12a begins. The attened tube portion 23 extends into spring 26, below the upper turns 27a. The attened portion 23 is caught between a pair of successive intermediate turns 23 of the spring. FIG. 2 shows spring 26 operative to retract tube 22, spring 26 being thereby extended. It will be apparent that when rell 22 is lowered, spring 26 is compressed, in the usual manner. The hour-glass shape of the spring facilitates entrance of the rell tube into the spring, if the spring remains entrapped in the barrel 12 during a change of refill.

It 'will further be apparent that assembly of the reill22 with casing 11 is carried out with the two

casing parts

12 and 13 separated, spring 26 dropped into barrel 12, tube 22 extended through spring 26 and cap 13 then placed upon lower barrel 12, thereby locating tube 22 extended through bushing bore 21.

Writing implement further comprises an impeller 40 mounted within casing 1|1 so as to be rotatable about the axis of the casing and so as to be accessible externally of the casing for rotation thereof. Specifically, impeller 40 has a cylindrical shank portion 41 'which is turna-bly received wit-hin bushing 42, this bushing 42 being iixedly received in the upper end of cap 13. Below bushing 42, shank 41 has a transverse peripheral flange 43 of increased diameter which is of the diameter of the bore of cap 13 and is turnable therein, said flange 43 being spaced from 42 by means of washer 44.

The upper end of shank 41 is at the level of the open upper end 13a of cap 13 and has a coaxial shaft extention 45 of reduced diameter which is received within knob 46. This knob 46 may take any suitable shape and is shown, strictly lfor illustrative purposes, as generally frusto-conical in shape and as downwardly tapered, with the lower end face of knob 46 being of about the same diameter as cap 13. Knob 46 has a bore 47 extending axially therein to its bottom face. Shaft 45 extends through bore 47. Knurtled portion 48 of shaft 45, of slightly increased diameter, is frictionally and nonturnably `force-fitted into bore 47. Washer 49 is mounted upon shank 41 between bushing 42 and knob 46. It will be apparent that the turning of cap 46 causes turning of impeller 40.

Below ange 43, shank 41, in the embodiment of FIGS. l-4 and 9-10, has a drum cam portion 50 of slightly increased diameter, The cam 50 is in the form of a helix which is clearingly received within the bore of cap 113. In this embodiment, the cam 50 may be formed by making a bore 51 extending axially in element 50 from the lower end thereof and also extendingl into shank 41.

Further, the element 50 may be formed with a helical screwthread 52 which is deep enongh to extend to the bore 51, as best shown in FIG. 4. The effect is to provide a helical cam surface 53 which optionally extends to cornplete turn. This cam surface 53 may be considered to be a drum cam surface of helical contour, it being understood that the term helical as used in the claims, will also encompass surfaces or edges usable in the same manner and having slightly different contours. In any event, this helical surface 53 is located in position so that the spring 26 maintains the upper end of tube 22 against such surface 53, as clearly shown in FIGS. 2 and 3. FIG. 2 shows the retracted condition of tube 22, in which its tip is wholly within casing 11 and in which the upper end of tube 22 abuts the upper portion of cam surface 53. In this position, the lower end portion of cam 50 abuts the side of tube 22, serving as a stop to prevent further retracting movement of cap 46. Accordingly, FIG. 2 shows one limit turned position of impeller 40.

When cap 46 is turned in the proper direction from its limit position of FIG. 2, the lower end of cam 50 moves away from the side of tube 22, and the upper end of tube 22 rides upon surface 53 so as to extend tube 22 so that the tip 25 is projected out of casing 11 through opening 15, as shown in broken lines in FIG. 2. The turning of cap 46 can be continued until the upper end of tube 22 is against the lower end portion of cam surface 53. At this lower end of surface 53, the surface 53 is provided with a stop projection 54 extending downwardly, as best shown in FIGS. 4 and 9. This projection 54 strikes the side of tube 22 to prevent further turning of impeller 40. This position of the parts, shown in FIGS. 3 and 9, corresponds to the other limit position of impeller 4t), corresponding to the extended position of tube 22. Without stop 54, if cap 46 were turned past such limit position, the tube 22 would be abruptly retracted to its position of FIG. 2 (see discussion of FIG. 8 below). With the provision of the stop, impeller 4G must be turned in the reverse direction from its limit position of FIG. 3 to its limit position of FIG. 2 in order to retract tube 22.

The impeller may be produced in a number of economical ways. The earn of FIG. 5 can be used instead of the cam 441 of the iirst embodiment. Elements 141, 143 and 145 correspond to

elements

41, 43 and 45 respectively. The shank 141 is provided with an axial bore 151 extending to the lower end thereof. The cam 150, which replaces cam 5d in this embodiment, is in the form of a wire having a straight axially extending upper end portion a embedded in bore 151 and a lower portion 152 shaped into the form of a helix corresponding dimensionally and operationally to the cam helix 52 of the tirst embodiment. The lower end of cam helix 152 is provided with a stop projection 154 corresponding to stop projection 54 of the first embodiment. The operation of the element 150 corresponds to that of element 50 and does not require any exteritled discussion.

In the embodiment of FIGS. 6-7, the

elements

241, 243 and 245 correspond to the

respective elements

41, 43 and 45 of the first embodiment. The cam element 250 is formed from a metal sheet 259 having a rear edge 259a, longitudinal long side edge 259b, longitudinal short side edge 259e and a straight edge 258 on the diagonal and connecting the front ends of the edges 259C and 2591?. At the connection zone of edges 258 and 2591;, a generally rectangular stop 257 is formed, extending forwardly of and slightly spacing the

edges

258 and 25%, as clearly shown in the developed plan view of FIG. 7.

To form the cam 250, the sheet 259 is rolled into tubular form, as shown in FIG. 6, with the edges 2591; and 259C adjacent each other. As a result, the edge 259a assumes a generally circular shape. Furthermore, the edge 258 asumes a helical contour. The stop 257 corresponds to the stop 5410i? the iirst embodiment. The edge 258 corresponds tothe surface 53 of the rst embodiment.

The formed cam 250 may be mounted in place upon the impeller 240 by any suitable means. Thus, an axial stud 255 may be embedded in the element 241 and extend downwardly therefrom. The upper portion of the tubular cam member 250 may be extended frictionally upon the stud 255 and secured thereto by any suitable means, with edge 259a abutting .element 243.

Cam 340 of FIG. 8 is quite similar to cam 40 of FIG. 4 and other views. However, the stop surface 354 of FIG. 8 is angular rather than the right angular stop 54 of FIG. 4. As a result, in the extension position of FIG. 3 (coma pare FIG. 12, in which the same impeller is used), although the stop is against the side of the actuated tube (or pin, FIG. 12), a slight additional torque causes the stop to override the top of the tube (or pin) and return to retraction position of FIG. 2 (FIG. 1l), permitting the tube (pin) to snap abruptly back to retracted position.

It will be apparent that the impeller, in addition to being formed from metal as shown, can also be formed by molding or other suitable process from plastic or other suitable material.

The operation of the implement should tbe readily apparent from the foregoing. As described in detail above, the cap maybe separated from the barrel and the spring and tube 22 mounted in place, and the cap returned so as to extend the tube 22 through bushing bore 21, with the upper ends of tube 22 against the cam surface 53. Knob 46 may then be manipulated to retract tube 22 with the lower end of cam 50 abutting the side of tube 22. Knob 46 may be turned in the opposite direction to extend tube 22, until stop 54 abuts the side of tube 22. In the impeller embodiment other than that of FIG. 8, knob 46 must be turned reversely to retract tube 22. This operation is also possible in FIG. 8, but alternatively, extra torque may be applied to carry the stop over the top of the tube and past it, to permit the tube to snap back to retracted position. f It will be apparent that the mechanical operation of implement 10 is extremely simple, and further, that the mechanism uses a minimum of parts, all of which are readily fabricated. Furthermore, the refill 22 is of standard type and may |be readily replaced.

FIGS. 1.7-13

This embodiment is the same as that of FIG. l, with the exception of the replacement of impeller 40 by impeller 349, as discussed above, and with the further exception of the replacement of tube 22 and tube 122 and pin 123. Of course, it will be understood that any of the previously described impellers may be used in this embodiment. In addition, because of the changed configuration of the tube, the spring 26 is replaced by spring 126.

Tube 122 is shorter than but of increased diameter relative to tube 22 and extends frictionally slidably through the bore of the barrel, terminating below bushing 2t). The lower end of tube 122 is of reduced diameter, at 122g, and then terminates in a still further reduced tip 12215. Tube portion 122:1 extends through the coil spring 126, with one end of spring 126 against the tapered barrel portion 112:1 and the other end of spring 126 against the main part of barrel 122. While barrel 12 is substantially the same as in the first embodiment, the tip 112a is optionally slightly more taperedand less rounded than tip 12a of the first embodiment. Tube 122 terminates at its upper end in a tube portion 122d of slightly decreased diameter.

Pin 123 extends slidably through the offset bore 21 of bushing 2t). The l-ower end of pin 123 engages the upper end of tube poition 122d. The upper end of pin 123 has a thin head 124 of slightly increased diameter which engages the cam 340.

The operation of this embodiment is entirely similar to the first embodiment, except that when knob 46 is turned, the impeller engages the pinhead 124 rather than the tube. FIG. l1 shows the retracted position of the impeller with the stop against the side of the pin. Fig. l2 shows the extended position of tube 122, with the stop against the head 124. It will be apparent that in the case of the particular cam 340, continued turning of cam 340 in direction to extend tube 122, with sufficient increased torque,

' will carry the stop past the head of the pin and back to its position of FIG. 1l, permitting labrupt snapback retraction of tube 122. Alternatively, for a gradual retraction, the direction of turning of knob 46 maybe reversed.

The head 124 is of greater diameter than bore 21 so as to prevent the pin from falling through the bore during the refill operation. g

While I have disclosed a preferred embodiment of my invention, and have indicated various possible changes, additions and omissions which may be made therein, it will be apparent that various other changes, omissions and additions may be made in the invention without departing from the scope and spirit thereof.

With reference to the claimed subject matter, it will be noted that in each embodiment there is an extension and retraction mechanism comprising a casing having a hollow tubular casing bore with an axis andan end axial opening 15. In each embodiment, there is a member in the bore (the tip 24 containing the ball, as illustratively shown in the first embodiment, but the member may take any other suitable form) in the bore and axially slidable between extended position, such as shown in broken lines in FIG. 2, in which the member (for example, tip 24) protrudes out of opening 15 and position of retraction of the member in the casing relative to its extended position,(such as shown in full lines in FIG. 2, lbut the mem'ber does not necessarily have to be fully retracted). In each embodiment, also, there are biasing means, illustratively shown as a spring, coupling the member and the casing and adapted to maintain the member n-ormally in retracted position.

In each embodiment, there is an impeller mounted within the casing bore spaced from the member (such as tip 24) and rotatable about its axis. In each embodiment, the impeller has an axial motion drum cam with a peripheral cam surface.

In each embodiment, there are means in the casing bore extending offset to the axis thereof and extending between the member and the cam surface. In the first embodiment, such offset means comprises the tube 22 itself which extends from the tip 24 toward the impeller, this tube 22 being offset to the axis since it extends through the offset bushing bore 21. In the embodiment of FIG. l1, the offset means takes the form of the pin 123 extending through the offset bushing bore 21 and extending between the peripheral surface and the tube 122 which may be considered to be an extension of the retractable and extendible member 122b.

Finally, in each embodiment, the cam surface and the offset means are shaped, sized and positioned so that the biasing means (the spring) maintains the end of the skew means (upper end of tube 22 or pinhead 124 as the case may be) against the cam surface. The cam surface is in each embodiment further shaped so that turning of the impeller to one turned position causes extension of the member and to another turned position permits the biasing means to retract the member.

What is claimed is:

1. Writing implement comprising an elongated barrel having open upper and lower ends, an elongated cap having an open lower end and releasably mounted on the upper end of said barrel in axial alignment therewith, a bushing fixed in said cap and having a bore offset from the common axis of said barrel and cap, a replaceable tube extending slidably through said bushing and said barrel and having lower end writing means of the type described, an impeller having a Ishank extending axially in said cap above said tube and turna-ble about said axis, said shank having means accessible externally of said cap for manipulation to turn said shank in either direction, said impeller also having a helix depending from said shank coaxially therewith, said helix having an edge surface engaging the upper end of said tube, and spring means coupling said tube and said barrel and urging said tube upwardly against said helix edge, said helix operative upon turning thereof in one direction to extend the lower end of said tube out of said barrel and in the other direction to retract said lower tube end into said barrel, said helix also having rst positive stop means thereon engaging the side of said tube upon extension of said tube to prevent further turning of said helix in tube extending direction so that the tube can be retracted only when the barrel is rotated in said other direction and second stop means on said helix engaging the side of said tube upon retraction of said tube to prevent further turning of said helix in tube retracting direction.

2. Writing implement according to claim ll, said rst stop means comprising a projection on the lower end of the edge surface of said helix.

3. Writing imple-ment comprising an elongated barrel having open upper and lower ends, an elongated cap hav ing an open lower end and releasably mounted on the upper end of said barrel in axial alignment therewith, a bushing xed in said cap and having a bore offset from the common axis of said barrel and cap, a pin extending slidably through said bushing and coaxial therewith, a replaceable tube extending slidably through said barrel coaxial therewith and having lower end Writing means of the type described, an impeller having a shank extending axially in said cap above said tube and turnable above said axis, said shank having means accessible externally of said cap for manipulation to turn said shank in either direction, said impeller also having a helix depending from said shank coaxially therewith, said helix having an edge surface engaging the upper end of said pin with the lower end of said pin engaging the upper end of said tube, and spring means coupling said tube and said barrel and urging said tube upwardly against the lower end of said pin thereby urging the upper end of said pin against said helix edge, said helix operative upon turning thereof in one direction to extend the lower end of said tube out of said barrel and in the other direction to retract said lower tube end into said barrel.

Cil

4. Writing implement according to claim 3, said helix also having first stop means thereon engaging the side of said pin upon extension of said tube to prevent further turning of said helix in tube extending direction and second stop means on said helix engaging the side of said pin upon retraction of said tube to prevent further turning of said helix in tube retracting direction.

5. Writing implement according to claim 3, said pin having a head at the upper end thereof, said helix also having stop means on said helix engaging the side of said pin upon retraction of said tube to prevent further turning of said helix in tube retracting position, and further stop means thereon engaging the side of said pin upon extension of said tube so as normally to prevent further f turning of said helix in tube extending direction, said further stop means being cam shaped and positioned relative to said pin head so that upon exertion of extra force for turning of said helix in tube extending direction the further stop means overrides and passes said pin head, said pin and tube then snapping back to retracted position.

6. Writing implement according to claim 4, said rst stop means comprising a projection on the lower end of the edge surface of said helix.

7. Writing implement according to claim 5, said further stop means comprising a projection on the lower end of the edge surface of said helix. i

References Cited by the Examiner UNITED STATES PATENTS 1,115,707 ll/l9l4 Marcus 74-99 1,511,566 10/1924 Kollock 74-66 2,865,331 12/1958 Marcotte 1Z0-42.03

FOREIGN PATENTS 518,042 3/ 1955 Italy.

EUGENE R. CAPOZIO, Primary Examiner.

H. F. ROSS, Assistant Examiner.

Claims

1. WRITING IMPLEMENT COMPRISING AN ELONGATED BARREL HAVING OPEN UPPER AND LOWER ENDS, AN ELONGATED CAP HAVING AN OPEN LOWER END AND RELEASABLY MOUNTED ON THE UPPER END OF SAID BARREL IN AXIAL ALIGNMENT THEREWITH, A BUSHING FIXED IN SAID CAP AND HAVING A BORE OFFSET FROM THE COMMON AXIS OF SAID BARREL AND CAP, A REPLACEABLE TUBE EXTENDING SLIDABLY THROUGH SAID BUSHING AND SAID BARREL AND HAVING LOWER END WRITING MEANS OF THE TYPE DESCRIBED, AN IMPELLER HAVING A SHANK EXTENDING AXIALLY IN SAID CAP ABOVE SAID TUBE AND TURNABLE ABOUT SAID AXIS, SAID SHANK HAVING MEANS ACCESSIBLE EXTERNALLY OF SAID CAP FOR MANIPULATION TO TURN SAID SHANK IN EITHER DIRECTION, SAID IMPELLER ALSO HAVING A HELIX DEPENDING FROM SAID SHANK COAXIALLY THEREWITH, SAID HELIX HAVING AN EDGE SURFACE ENGAGING THE UPPER END OF SAID TUBE, AND SPRING MEANS COUPLING SAID TUBE AND SAID BARREL AND URGING SAID TUBE UPWARDLY AGAINST SAID HELIX EDGE, SAID HELIX OPERATIVE UPON TURNING THEREOF IN ONE DIRECTION TO EXTEND THE LOWER END OF SAID TUBE OUT OF SAID BARREL AND IN THE OTHER DIRECTION TO RETRACT SAID LOWER TUBE END INTO SAID BARREL, SAID HELIX ALSO HAVING FIRST POSITIVE STOP MEANS THEREON ENGAGING THE SIDE OF SAID TUBE UPON EXTENSION OF SAID TUBE TO PREVENT FURTHER TURNING OF SAID HELIX IN TUBE EXTENDING DIRECTION SO THAT THE TUBE CAN BE RETRACTED ONLY WHEN THE BARREL IS ROTATED IN SAID OTHER DIRECTION AND SECOND STOP MEANS ON SAID HELIX ENGAGING THE SIDE OF SAID TUBE UPON RETRACTION OF SAID TUBE TO PREVENT FURTHER TURNING OF SAID HELIX IN TUBE RETRACTING DIRECTION.