FR3006302A1 - ROTARY SHAFT TYPE MANUAL OPENER WITH WHEEL AND HANDLE HANDLE - Google Patents

Abstract

The present invention relates to a manual can opener, of the rotary shaft type (11) of longitudinal axis (L), carrying a wheel (17), and a free end (12) is provided with means (13) for its secured to a rotary handle (14). According to the invention, said securing means (13) between said rotary shaft (11) and said rotary operating handle (14) comprise at least one ratchet device (31, 32, 38, 47), arranged to allow the rotating said rotary shaft (11) about said longitudinal axis (L) only in a first direction of rotation, by the operation of said rotary handle (14).

Description

TECHNICAL FIELD TO WHICH THE INVENTION RELATES The present invention relates to the field of can openers for the opening of cans. It relates more particularly to a rotary shaft type manual can opener provided with a wheel and a rotary operating handle. It relates even more particularly to a clip-type can opener, comprising two arms hinged together about an axis of articulation, and provided, for one, a notched drive wheel, and for the another, a cutting wheel.

BACKGROUND ART Various types of can openers can be used to open canned goods. Among them, there are manually operated can openers, comprising a rotary handle that actuates a rotary shaft equipped with a knob. More specifically, some of these openers are of the clamp type, comprising two arms articulated together about a hinge axis. One of these two arms is used to support the rotary shaft equipped with the rotary operating handle, at one of its ends. Its other end is equipped with a toothed wheel that serves to advance the cutting on the box that you want to open; this toothed drive wheel is integral in rotation with the rotary shaft and is associated with a first toothed gear, also integral in rotation with said rotary shaft.

The other of the two arms comprises a pin or cylindrical pin on which are mounted - a second toothed gear, arranged to be engaged with said first pinion, and - a cutting wheel integral in rotation with said second pinion gear. The cutting wheel and the second gear are mounted with a possibility of rotation on their cylindrical support axis. The cutting wheel is rotated by the operating handle, by means of the first and second toothed gears. To open a can, the user operates the can opener using the operating handle, by a succession of rotational movements, generally in the direction of clockwise, to ensure its moving and cutting the lid on at least part of its periphery. In case of blockage, or when the opening is completed, the user can move the handles to extract the device and in particular the cutting wheel metal parts tight on both sides. The major disadvantage of this type of can opener is that during the opening operations, the user is required to release and intermittently maintain the rotating handle, at each rotational movement, for example a half -turn, which makes the maneuver complex, relatively long and difficult. Such devices do not fully open a can without releasing the operating handle. OBJECT OF THE INVENTION The present invention aims to provide an original can opener to solve the aforementioned drawbacks. This objective is achieved by the design of a can opener incorporating a ratchet mechanism (s) that allows the opening of a can without releasing the operating handle, when in use.

For this purpose, the manual can opener according to the invention, of the rotary shaft type having a longitudinal axis L, carrying a wheel, and a free end of which is provided with means for securing it to a rotary operating handle, is characterized in that said securing means between said rotary shaft and said rotary operating handle comprise at least one ratchet device arranged to allow the rotary drive of said rotary shaft about said longitudinal axis L only in a first direction of rotation, by the operation of said rotary handle. According to a preferred embodiment, this can opener is of the clamp type, comprising two arms hinged together about an axis of articulation; one of these arms serves as a support for said rotary shaft, said operating handle being integral with one end of the rotary shaft via said one or more ratchet devices; in addition, a drive wheel, and a first toothed gear, are carried by the other end of the rotary shaft, secured in rotation with the latter.

For its part, the other of said arms comprises a cylindrical axis on which are mounted - a second toothed gear, arranged to be engaged with said first toothed gear, and - a cutting wheel, integral in rotation with said second toothed gear.

According to another feature, said securing means between the rotary shaft and the rotary operating handle further comprise means arranged to allow the deactivation of the ratchet device and the rotational drive of the rotary shaft about its longitudinal axis L in the second direction of rotation, the reverse of the first.

In a preferred embodiment, said shaft / handle fastening means comprise: a first ratchet device arranged to allow the rotary shaft to be driven in rotation about its longitudinal axis L only in a first direction of rotation, by the rotation of said handle, - a second ratchet device, arranged to allow the rotational drive of the rotary shaft about its longitudinal axis L, only in the second direction of rotation, the inverse of the first, by the rotating said handle, and - means for selecting activation of said first or second ratchet device. According to yet another feature, the can opener comprises at least one ratchet device comprising: - a ring gear, centered on said longitudinal axis L, provided with a plurality of teeth defining between them a plurality of grooves, which teeth comprise each a drive and a retraction panel, - a transverse axis, perpendicular or substantially perpendicular to said longitudinal axis L, extending diametrically with respect to said ring gear, said ring gear being movable relative to said transverse axis, the along said longitudinal axis L, to allow, or the cooperation of said transverse axis with the teeth of said ring gear, by introduction into said grooves, for the activation of said ratchet device, to allow the rotational drive of said rotary shaft only in one direction of rotation, ie the separation of said axis of the teeth of said ring gear, for the deactivation of the it ratchet device.

Still advantageously, the can opener comprises a transverse axis which is arranged between two toothed rings opposite and separated from one another, said transverse axis being movable along said longitudinal axis L, with respect to said toothed crowns , to allow its cooperation with one of said toothed rings, to allow the rotational drive of said rotary shaft only in a first direction of rotation, or with the other of said toothed rings to allow the rotary drive of said rotary shaft only in the second direction of rotation, inverse of said first.

According to another particular feature, the one or more toothed rings are formed on one of the end faces of a carrier cylinder whose central orifice extends coaxially with the longitudinal axis L, the opposite end face of said carrier cylinder constituting a bearing face. In this context, the rotary shaft advantageously extends through the central orifice of said cylinders carrying said toothed crowns, and carries said transverse axis, said rotary shaft being movable in translation, with respect to said toothed crowns, along said axis. longitudinal L, over a limited distance, defined by the cooperation of said transverse axis with said toothed crowns.

In a particularly interesting manner, resilient return means are arranged so as to tend to cooperate said transverse axis with one of said toothed crowns. According to yet another particularly interesting embodiment, the can opener comprises a tubular body provided with means for securing with said operating handle. This tubular body extends coaxially with said longitudinal axis L, and incorporates said cylinders carrying said toothed crowns, fixed by any appropriate means, coaxially with each other and coaxially with said tubular body. This tubular body further integrates a portion of said rotary shaft, with said transverse axis located between said bearing cylinders; resilient return means in the form of helical spring are further provided to tend to cooperate said transverse axis with said ring gear of one of said carrier cylinders. In this context, the rotary shaft advantageously comprises a shoulder and receives successively, starting from said shoulder: a first carrier cylinder provided with a ring gear, said transverse axis and a second carrier cylinder provided with a ring gear, an axial screw , housed in the free end of said rotary shaft, being adapted to keep the tubular body movable on said rotary shaft. In a first embodiment, a helical spring is interposed between the shoulder of said rotary shaft and the bearing face of the facing carrier cylinder, adapted to tend to cooperate said ring gear of said carrier cylinder with said transverse axis. In an alternative embodiment, a helical spring is interposed between the head of the axial screw fixed to the end of the rotary shaft and the bearing face of the facing carrier cylinder, said coil spring being adapted to tend to cooperate said transverse axis with the ring gear of said carrier cylinder facing. According to yet another characteristic, said tubular body is secured to said rotary handle by means of at least one fixing screw. The present invention therefore provides a can opener very simple structure, which allows the opening of a box without the user need to release the hand of the operating handle. The user can constantly maintain the rotary operating handle during the forward rotation movement, linked to the opening of the box, and also during the rear rotation movement, possibly necessary to extract the tight can opener on the metal sheets at the end of the procedure. This invention simplifies the use of openers and reduce the time required for opening the boxes.

DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT The invention will be further illustrated, without being limited in any way, by the following description of a particular embodiment, given solely by way of example and represented in the appended drawings in which: Figure 1 is a schematic, exploded overall view of a ratchet opener according to the invention; - Figure 2 is a top view of the can opener illustrated in Figure 1, once its various constituent parts assembled together; Figure 3 is a side view of the can opener illustrated in Figure 2 (seen from the side of its drive and cutting wheels); FIG. 4 is a cross-sectional view of the can opener along sectional plane 4-4 of FIG. 2; FIG. 5 is a partial schematic view showing the structure of one of the elements of the tubular body in which the ratchet mechanism is integrated; - Figure 6 is a schematic perspective view of a carrier cylinder of the ratchet mechanism revealing the detail of the shape of the teeth of its ring gear; - Figure 7 is a side view of the carrier cylinder shown in Figure 6. The can opener 1 shown in Figures 1 to 4 is of the clamp type. It comprises, in a conventional manner, a main arm 2, formed of a handle 3 extended by a head 4, and a secondary arm 5, formed of a handle 6 extended by a head 7, these two arms 2 and 5 being articulated between them around an axis 8. This hinge pin 8 is located approximately between the sleeves 3, 6 and the heads 4, 7 of the two arms 2 and 5. This hinge pin 8 is embodied by a screw or a rivet 8a visible in Figures 2 and 3. The head 4 of the main arm 2 is generally flat and has an orifice 9 receiving an attached cylindrical ring 10, for the passage and guiding of a rotary shaft 11 through axis This rotary shaft 11 extends on each side of the flat head 4.

On one side of this flat head 4, the free end 12 of the rotary shaft 11 comprises means 13 for securing it with a rotary operating handle 14, these securing means 13 incorporating ratchet devices, in accordance with FIG. present invention, as detailed later in the description.

On the other side of this flat head 4, the free end 15 of the rotary shaft 11 receives, in a conventional manner, a first toothed gear 16 and a toothed drive wheel 17, separated by a washer 18. This first toothed gear 16 and the toothed wheel 17 each comprise a central orifice for their fitting on the end 15 of the shaft 11. They are held tight on the shaft 11 and secured in rotation therewith by any appropriate means such as stamping, crimping or screwing. Between its two ends 12 and 15, the rotary shaft 11 has a shoulder 20 disposed on the side of the operating handle 14 relative to the flat head 4. This shoulder 20 bears against the opposite end of the ring 10 Note that the ring 10 abuts against the flat head 4, the side of the pinion 16 and the knob 17, via a shoulder, and that, on the side of the operating handle 14, its end protruding from the flat head 4 is associated with an insert ring 21, force-fitted, to ensure its locking. For its part, still in known manner, the head 7 of the secondary arm 5 is generally flat and has a cylindrical axis 22 on which is mounted a second toothed gear 23 and a cutting wheel 24. The second toothed gear 23 and the cutting wheel 24 each comprise a central orifice for mounting on a support ring 25 which ensures their rotation integral. This support ring 25 itself comprises a central orifice for its fitting on the axis 22. The ring 25 (with the second toothed gear 23 and the cutting wheel 24) is held on this axis 22 by the head of a screw axial 26. It can rotate on the axis 22. In addition, the second pinion gear 23 is engaged with the first pinion gear 16, so that a rotation of the first pinion 16 (driven by the rotary shaft 11 actuated by the operating handle 14) causes the rotation of the second gear pinion 23 and that of the cutting wheel 24. When opening a can with the opener 1, the advancement of the cutting is obtained by means of the toothed wheel 17. Still conventionally, the axis 22 is slightly inclined to optimize cutting by the wheel 24. It will be noted again, still in a known manner, the presence of shaped uncapping members 27 at the end of the flat head 4, in particular for uncapping the lid of some jars glass or other.

The operating handle 14 is here in the form of a U-section structure formed of a base 14a extended by two parallel side wings 14b. The securing means 13 between the operating handle 14 and the rotary shaft 11 (more precisely its free end 12) comprise a tubular body 30 in which are integrated two bearing cylinders 31 and 32 which each bear on their faces facing each other. , a ring gear 33 and 34. The tubular body 30 is formed here of two cylinders, one outer 30, for example stamped stainless steel, and the other inner 30b, for example injected plastic, coaxial, fitted one in the other. Each of the bearing cylinders 31 and 32 has a central orifice 35, 36 allowing the introduction of the free end 12 of the rotary shaft 11, this free end 12 being provided with a diametrical orifice opening 37, in which is inserted at A transverse axis 38 carried by the rotary shaft 11 protrudes on either side of the latter, so that its projecting ends can cooperate with the toothed rings 33 and 34 of the cylinders. carriers 31 and 32.

Each ring gear 33 and 34 of the bearing cylinders 31 and 32 is intended to cooperate with the ends of the transverse axis 38 to form a ratchet device, in association with elastic return means, as described later in the description. The free end 12 of the rotary shaft 11 has an axial orifice 39 which opens into its end face. The two bearing cylinders 31 and 32 have an outer diameter which corresponds, with the clearance, to the inner diameter of the tubular body 30 (and more particularly of the inner cylinder 30b). They are inserted in the latter with their ring gear 33, 34 facing and spaced apart from each other by a certain distance. These two bearing cylinders 31 and 32 are fixed in the tubular body 30 by any appropriate means. For example, fixing screws 40 are used which are housed in orifices 41 and 42 for securing the support roll 31 with the tubular body 30, and fixing screws 43 which are housed in orifices 44 and 45 for the fastening of the carrier cylinder 32 with the tubular body 30 (the fastening screws in question 40, 43 do not extend in the bulk of the central orifice 35, 36 of the bearing cylinders 31 and 32). The transverse axis 38 is arranged between the two bearing cylinders 31 and 32. For this, the carrier cylinder 32 is fitted on the free end 12 of the rotary shaft 11 before fitting the shaft 38 in its diametrical orifice 37 of reception, and before joining of this carrier cylinder 32 with the tubular body 30.

A helical compression spring 47 is interposed between the flat face 48 of the support cylinder 31 (opposite its ring gear 33) and the head of an axial screw 49 inserted into the axial end orifice 39 of the rotary shaft 11 The head of this axial screw 49 can be associated with a washer.

This coil spring 47 is adapted, here, to tend to cooperate the ends of the transverse axis 38 with the toothing of the ring gear 33 of the carrier cylinder 31 located on the side of the operating handle 14. On its side, the face 50 of the carrier cylinder 32, opposite its ring gear 34, constitutes a plane face which abuts against the shoulder 20 of the rotary shaft 11. The tubular body 30 is inserted by one of its ends into the handle of maneuver 14 between its two lateral wings 14b. This tubular body 30 is secured to the handle 14 by means of two screws 51 which are housed, vis-à-vis, on either side of the handle 14, each - in an orifice 52 formed in one side wings 14b of the handle 14, - in an orifice 53 formed in the tubular body 30, and - in an orifice 54 formed in the carrier cylinder 31, all adapted accordingly. As can be seen in FIGS. 1 and 5 to 7, advantageously, the bearing cylinders 31 and 32 comprise two diametrically opposed lateral lugs 55 arranged to cooperate with grooves 56 formed in the tubular body 30 (and more particularly in its inner cylinder 30b), to ensure their guidance within the latter during assembly, and their correct angular positioning for the establishment of the aforementioned fixing screws 40, 43.

As can be seen in Figures 1 and 5, these grooves 56 are formed in pairs on generatrices parallel to the axis of the tubular body 30 and they are diametrically opposed. Note that these grooves 56 open at the ends of the cylinder 30b, but they do not extend over its entire length. They are indeed interrupted in the central portion 57 of said cylinder 30b (and therefore of said tubular body 30) to constitute a positioning stop, a function of the desired relative positioning of the bearing cylinders 31 and 32, and the desired spacing of the toothed rings 33 and 34 opposite, for their cooperation with the transverse axis 38, as described below. The two bearing cylinders 31 and 32 are identical. Their structure is detailed in FIGS. 6 and 7. As can be seen in these two FIGS. 6 and 7, the bearing cylinders 31 and 32 are in the form of a cylinder of axis A, provided with a central orifice 35, 36. One of the end faces of this cylinder 31, 32 comprises the ring gear 33, 34, centered on the axis A, and which extends in a plane perpendicular to said axis A. The other face end 48, 50 is flat and also extends in a plane perpendicular to said axis A. On the periphery of the cylindrical casing of the cylinders 31, 32, we note the presence of the two guide lugs 55, diametrically opposed. The bearing cylinders 31, 32 also comprise the aforementioned orifices which open into its cylindrical envelope, perpendicular to the axis A, namely: the orifice 44 for fixing on the tubular body 30 (for the carrier cylinder 32), fixing holes 54 on the handle 14 (for the carrier cylinder 31), and - the fixing orifice 41 on the tubular body 30 (for the carrier cylinder 31).

The presence of these different orifices makes it possible to have a single piece serving for the two bearing cylinders 31 or 32. The toothing of the ring gear 33, 34 comprises a juxtaposition of teeth 60, for example 6 to 10 teeth, preferably 8. These teeth 60 are identical and their shape is adapted to obtain the desired ratchet function.

For this, each tooth 60 comprises a pan 61 which extends in a radial plane parallel to the axis A (to constitute a rotating drive, by the cooperation with the transverse axis 38, during the rotation of the handle 14 in a direction of rotation), and a panel 62 which extends in a substantially radial plane, but which is inclined with respect to the axis A (constituting a retraction panel, to allow the sliding or the passage of the transverse axis 38, without driving cooperation with the carrier cylinder 31, 32, during the rotation of the handle 14 in the other direction). Between the different teeth 60 juxtaposed, note the presence of the grooves 63 for receiving and positioning the ends of the transverse axis 38. Once the can opener 1 assembled, as shown in Figures 2, 3 and 4, the handle 14, the tubular body 30, the two bearing cylinders 31 and 32, and the rotary shaft 11 extend coaxially.

The handle assembly 14, tubular body 30 and bearing cylinders 31, 32 is axially movable on the rotary shaft 11, this mobility being limited over a certain distance, defined by the cooperation of the transverse axis 38 with the toothed rings 33, 34 of the two bearing cylinders 31, 32. The two toothed rings 33, 34 of the bearing cylinders 31, 32 are separated from each other by a suitable distance. The transverse axis 38 extends diametrically with respect to said toothed rings 33, 34. In the rest position, the coil spring 47 constrains the transverse axis 38 to cooperate with the ring gear 33 of the support cylinder 31 located on the handle side 14.

The toothing of the ring gear 33 of the support cylinder 31 located on the handle side 14 is adapted to allow the rotational drive of the rotary shaft 11, when this toothing cooperates with the transverse axis 38, this in a single direction of rotation of the handle 14, here in the direction of rotation of the clockwise; and the toothing of the toothed crown 34 of the support roll 32, located on the shoulder side 20, is adapted to allow the rotational drive of the rotary shaft 11, when this toothing cooperates with the transverse axis 38, this when the handle 14 is operated in the other direction of rotation (here in a direction contrary to the direction of rotation of the needles of a watch).

Thus, it is understood that a rotation of the operating handle 14 in the direction of rotation of the hands of a clock ensures the rotation of the rotary shaft 11 and allows the opening of a can by the cutting wheel 24.

This opening is achieved by a succession of rotational and counter-rotating movements, without releasing the operating handle 14, the counter-rotation movements (clockwise inversions) not causing the rotation of the latch. 11, because of the ratchet device 33, 38, 47 and the passage of the transverse axis 38 on the inclined faces 62 of the ring gear 33. Once the opening of the box made, the operator can pull on the operating handle 14, against the restoring force exerted by the helical spring 47, to cooperate the transverse axis 38 with the toothing 34 of the support cylinder 32, so as to allow rotation of the shaft rotary 11 in the other direction, in particular to allow the extraction of the cutting wheel 24 if it is locked or clamped in the metal sheets of the open box. In an alternative embodiment, the helical spring 47 can be omitted, and a new helical spring (possibly the same) can be interposed between the bearing face 50 of the carrier cylinder 32 and the shoulder 20 of the rotary shaft 11. In this case, the head of the screw 49 is adapted to serve as a stop to the carrier cylinder 31 (by its bearing surface 48), or this screw 49 is associated with an end washer.

The double pawl mechanism then operates in a manner similar to the embodiment described above (in the rest position, it is then the ring gear 34 of the carrier cylinder 32 which cooperates with the axis 38). Still in an alternative embodiment, it will be possible to provide a single ring gear, adapted to cooperate with the transverse axis 38, to form a single ratchet device, this possibly in combination with means which allow the deactivation of this ratchet device and which allow the rotational drive of the rotary shaft in the other direction of rotation.

Claims (14)

CLAIMS 1.- A manual can opener, of the rotary shaft type (11) of longitudinal axis (L), carrying a knob (17), and a free end (12) is provided with means (13) for its secured to a rotary operating handle (14), characterized in that said securing means (13) between said rotary shaft (11) and said rotary operating handle (14) comprise at least one ratchet device (33, 34, 38, 47) arranged to allow the rotational drive of said rotary shaft (11) about said longitudinal axis (L) only in a first direction of rotation, by the operation of said rotary handle (14). 2. A can opener according to claim 1, characterized in that it is of the clamp type, comprising two arms (2, 5) hinged together about a hinge axis (8), one of said arm (2) serving as a support for said rotary shaft (11), said operating handle (14) being integral with one of the ends (12) of said shaft (11) via said one or more ratchet devices (33, 34, 38, 47), and a drive wheel (17) and a first toothed gear (16), being carried by the other end (15) of said shaft (11), secured in rotation with the latter, the other of said arms (5) having a cylindrical axis (22) on which are mounted - a second toothed gear (23), arranged to engage said first toothed gear (16), and - a cutting wheel (24) ), integral in rotation with said second pinion gear (23). 3. A can opener according to any one of claims 1 or 2, characterized in that said securing means (13) further comprise means arranged to allow the deactivation of said ratchet device (33, 34, 38, 47). and rotating said rotary shaft (11) about said longitudinal axis (L) in the second direction of rotation, opposite to the first. 4. Can opener according to any one of claims 1 to 3, characterized in that said securing means (13) between said rotary shaft (11) and said operating handle (14) comprise: - a first device to pawl (33, 38, 47) arranged to allow the rotational drive of said rotary shaft (11) about its longitudinal axel (L), only in a first direction of rotation, by the rotation of said handle (14), a second ratchet device (34, 38, 47) arranged to allow the rotational drive of said rotary shaft (11) about said longitudinal axis (L), only in the second direction of rotation, inverse of the first, by the maneuver; rotating said handle (14), and - means (14, 47) for selecting activation of said first or second ratchet device. 5. A can opener according to any one of claims 1 to 4, characterized in that it comprises at least one ratchet device (33, 34, 38, 47) comprising: - a ring gear (33, 34) , centered on said longitudinal axis (L), provided with a plurality of teeth (60) defining between them a plurality of grooves (63), which teeth (60) each comprise a driving pan (61) and a pan retraction (62), - a transverse axis (38), perpendicular or substantially perpendicular to said longitudinal axis (L), extending diametrically with respect to said ring gear (33, 34), said ring gear (33, 34) being movable relative to said transverse axis (38), along said longitudinal axis (L), to allow or cooperation of said axis (38) with the teeth (60) of said ring gear (33, 34), by introduction into said grooves (63) for activating said ratchet device to allow rotation of said rotat shaft if (11) only in one direction of rotation, ie the separation of said axis (38) of the teeth (60) of said ring gear (33, 34), for the deactivation of said ratchet device. 6. Can opener according to claim 5, characterized in that it comprises a transverse axis (38) which is arranged between two toothed rings (33, 34) opposite and separated from each other, said axis transverse beam (38) being movable along said longitudinal axis (L), with respect to said toothed crowns (33, 34), to allow its cooperation - with one of said toothed crowns (33, 34), in order to allow the drive rotating said rotary shaft (11) only in a first direction of rotation, or - with the other of said toothed rings (33, 34) to allow rotation of said rotary shaft (11) only in the second direction of rotation, inverse of said first. 7. A can opener according to any one of claims 5 or 6, characterized in that the toothed crown or rings (33, 34) are formed on one of the end faces of a carrier cylinder (31). 32) whose central orifice (35, 36) extends coaxially with the longitudinal axis (L), the opposite end face (48, 50) of said support cylinder (31, 32) constituting a face of support. 8.- Can opener according to claims 6 and 7, taken in combination, characterized in that the rotary shaft (11) extends through the central orifice (35, 36) of said bearing cylinders (31, 32 ) of said ring gear (33, 34), and carries said transverse axis (38), said rotary shaft (11) being movable in translation, with respect to said ring gear (33, 34), along said longitudinal axis (L) on a limited distance, defined by the cooperation of said transverse axis (38) with said toothed crowns (33, 34). 9. A can opener according to any one of claims 5 to 8, characterized in that it comprises elastic return means (47), arranged so as to tend to cooperate said transverse axis (38) with the or one of said toothed crowns (33, 34). 10. A can opener according to any one of claims 8 or 9, characterized in that it comprises a tubular body (30) provided with securing means (51) with said operating handle (14), which tubular body (30) extends coaxially with said longitudinal axis (L), and integrates said bearing cylinders (31, 32) of said toothed rings (33, 34), fixed by any appropriate means (40, 43), coaxially with each other and coaxially with said tubular body (30), which tubular body (30) further integrates a portion of said rotary shaft (11), with said transverse axis (38) located between said bearing cylinders (31, 32), spring-like elastic return means helical (47) being further provided to tend to cooperate said transverse axis (38) with said ring gear (33, 34) of one of said carrier cylinders (31, 32). 11. A can opener according to claim 10, characterized in that the rotary shaft (11) comprises a shoulder (20) and receives successively, starting from said shoulder (20): a first carrier cylinder (32) provided with a toothed crown (34), said transverse axis (38) and a second carrier cylinder (31) provided with a ring gear (33), an axial screw (49), housed in the free end of said rotary shaft (11), being adapted to hold the tubular body (30) movable on said rotary shaft (11). 12. A can opener according to claim 11, characterized in that it comprises a helical spring interposed between the shoulder (20) of said rotary shaft (11) and the bearing face (50) of the carrier cylinder (32). opposite, adapted to tend to cooperate said ring gear (34) of said carrier cylinder (32) with said transverse axis (38). 13. A can opener according to claim 11, characterized in that it comprises a helical spring (47) interposed between the head of the axial screw (49) fixed to the end of the rotary shaft (11) and the bearing face (48) of the supporting cylinder (31) opposite, said helical spring (47) being adapted to tend to cooperate said transverse axis (38) with the ring gear (33) of said support cylinder (31) facing . 14. A can opener according to any one of claims 10 to 13, characterized in that said tubular body (30) is secured to said rotary operating handle (14) by means of at least one fixing screw (51).