Stir stick dispenser for a beverage vending machine and method for dispensing a stir stick

Abstract

A stir stick dispenser (30) and a method for dispensing a stir stick (2) in a beverage vending machine (A), wherein a stir stick (2) is extracted from a stack (4) of stir sticks (2) via an extractor (31) reciprocally movable between a retracted rest position and an advanced extraction position, and is pushed out by moving the stir stick away from the extractor (31) and applying an expulsion thrust by a swing lever during the movement of the extractor (31) towards its advanced position.

Description

[0001] Cross-citation of related applications

[0002] This patent application claims priority to European Patent Application No. 21204073.7, filed on October 21, 2021, and Italian Patent Application No. 102021000028715, filed on November 11, 2021, the disclosures of which are incorporated herein by reference. Technical Field

[0003] This invention relates to a stir bar dispenser for a beverage vending machine and a method for dispensing the stir bar. Background Technology

[0004] In the vending machine industry, it is known that beverage vending machines have a stir bar dispenser inside, and that the stir bar dispenser is controlled by the electronic control unit of the beverage vending machine to dispense the stir bar directly into the beverage cup.

[0005] The stir bar is typically released into the cup before it is filled with the beverage, and the dispensing can be done in response to a user's request to add sugar to a selected beverage.

[0006] Typically, known stir bar dispensers include a stir bar box and an extractor. The stir bar box contains one or more rows of stir bars stacked in an orderly fashion. The extractor is operated in use to move reciprocally and laterally relative to the stir bar through the lower outlet of the stir bar box so as to eject only the stir bar located at the bottom of the stack by the back-and-forth movement through the lower outlet, and to make it fall directly into the cup or onto a slider that drives it to the cup.

[0007] Stirring bar dispensers of the above type are known, for example from EP 1 586 254 A1, EP 2 345 010 A1 and EP 2 563 187 A1.

[0008] The aforementioned type of stir bar dispenser has been used quite satisfactorily for dispensing plastic stir bar dispensers for decades, but with the recent enactment of environmental protection regulations, as long as plastics are banned, the aforementioned type of stir bar dispenser has exposed serious shortcomings, and operators in this field are obligated to adopt alternative "green" solutions, particularly using stir bar dispensers made of biodegradable or compostable materials such as wood or paper.

[0009] The problems associated with the use of wooden or paper stirring rods in traditional dispensers stem from the fact that in these dispensers, the extractor, stirring rod box, and stirring rod stack are configured to interact with each other with high precision, such that movement of the extractor enables the extraction of individual rods from the bottom of the stack.

[0010] For plastic stir sticks, this precision is generally guaranteed over time by the fact that the shape and size of the stir sticks stacked in the stick magazine remain substantially stable regardless of the environmental conditions inside the automatic dispenser.

[0011] Conversely, in the case of stir sticks made of materials other than plastic, in particular wood and paper, the same precision cannot be guaranteed, since, as is well known, these materials are greatly affected by temperature and humidity variations and can warp to such an extent that the action of the extractor becomes ineffective, resulting in the jamming of the stick dispenser.

[0012] The problem of stir stick deformation is at least partially solved by the dispenser described in Italian patent application No. 102021000007343 filed by the current applicant, in which the extractor that moves back and forth can extract a single stir stick at a time regardless of whether the stir stick is deformed.

[0013] In the known stir stick dispensers, in some cases, although the extraction is successful, the stir stick dispenser is still jammed or in any case malfunctions.

[0014] Experimental findings have shown that the above problems are mainly due to the fact that, once removed from the stack, the stir sticks continue in the desired manner towards the inlet of the duct, while in other completely unpredictable cases, the stir sticks continue to remain partially coupled to the extractor, which usually causes the stir sticks to return and then release them at any point and usually in a position different from that envisaged for a correct entry into the falling duct. SUMMARY

[0015] The aim of the present application is to provide a stir stick dispenser for a beverage vending machine that makes it possible to solve the above problems.

[0016] According to the present application, a stir stick dispenser for a beverage vending machine is provided as defined in the attached claims. BRIEF DESCRIPTION OF DRAWINGS

[0017] The present application will now be described with reference to the attached drawings, which show non-limiting embodiments of the present application, in which:

[0018] Figure 1 a beverage vending machine with a stir stick dispenser according to a preferred embodiment of the present application is shown schematically and partially;

[0019] Figure 2 and Figure 3 is shown Figure 1 the side perspective view of the stir stick dispenser shown in two different operating conditions, with some parts removed for the sake of clarity;

[0020] Figure 4 and Figure 5 a detail of the stirring stick dispenser shown in section and in enlarged scale, arranged in two different operating conditions; Figure 1 and

[0021] Figure 6 a variant of the stirring stick dispenser according to the present application is shown;

[0022] Figure 7 and Figure 8 a detail of the stirring stick dispenser shown in section and in enlarged scale, arranged in two different operating conditions; Figure 6 and

[0023] Figure 9 and Figure 10 a detail of the stirring stick dispenser shown in section and in enlarged scale, arranged in two different operating conditions; Figure 6 DETAILED DESCRIPTION

[0024] The present application will now be described in detail by making reference to the attached drawings, in order to enable the person skilled in the art to implement and use it. Various modifications to the described embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the scope of the present application as defined in the appended claims. Therefore, the present application should not be considered limited to the embodiments described and shown herein, but should be allowed the widest scope consistent with the features described and claimed herein.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. In case of conflict, the present specification, including the provided definitions, will control. In addition, the use of particular examples in the description is merely for illustrative purposes and, therefore, should not be considered to be limiting.

[0026] In order to facilitate the understanding of the embodiments described herein, reference will be made to some specific embodiments and specific language will be used to describe these embodiments. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present application.

[0027] In Figure 1 A as a whole refers to the beverage vending machine partially shown.

[0028] The beverage vending machine A comprises a stirring stick dispenser 1 to automatically dispense individual stirring sticks 2 one at a time into a cup B arranged to receive a beverage to be mixed.

[0029] ​As shown in the attached drawings, the above-mentioned stirring bars 2 are shaped as elongated flat elements each having a longitudinal axis 2' and comprising two rounded end portions 2A and an intermediate portion 2B defined by two main flat faces 2B1 and two straight narrow edges 2B2. While this is the most common shape of stirring bars 2, in which case the stirring bars are also commonly referred to as mixing paddles, however, the stirring bar dispenser of the present invention is configured to also dispense stirring bars of different sizes or shapes than the ones of the illustrated example. For instance, the stirring bars can not be flat or only partially flat and / or have a circular or similar shaped cross section.

[0030] The stirring bar dispenser 1 comprises a fixed attachment frame T and a stirring bar magazine 3 designed to contain a stack 4 of stirring bars 2 orderly stacked on top of each other and loaded with a weight (not shown).

[0031] The stirring bar dispenser 1 further comprises an extractor 5 arranged below the magazine 3 and having a support surface 6 at the top which supports the stack 4 of stirring bars 2 in the stirring bar magazine 3 when the extractor 5 is in a resting position.

[0032] The extractor 5 further comprises a pusher 7 mounted to move back and forth with respect to the magazine 3 to laterally engage a stirring bar 2 resting on the support surface 6, thereby pushing the stirring bar laterally through an outlet 8 of the magazine 3 until the stirring bar is completely extracted from the stack 4 and freely falls down.

[0033] In the preferred embodiment shown in the attached drawings, the support surface 6 and the pusher 7 are integrally formed and both formed on the extractor 5, which in this case is in the form of a rotating member hinged to the attachment frame T to reciprocally pivot about a fixed axis 9 parallel to the longitudinal axis 2' of the stirring bars 2 in the stirring bar magazine 3.

[0034] In particular, the extractor 5 comprises an arm 10 whose lower end is hinged to the attachment frame T to rotate about the fixed hinge axis 9 and whose upper end is connected to an upper head portion 11.

[0035] In particular, as shown in Figs. 1 and 2, the head portion 11 comprises a lowered portion or support portion 12 whose upper surface is the above-mentioned support surface 6 and an elevated portion 13 arranged on the side of the stirring bar magazine 3 opposite the outlet 8 when the extractor 5 is in the resting position. Figure 4 and Figure 5 In particular, as shown in Figs. 1 and 2, the head portion 11 comprises a lowered portion or support portion 12 whose upper surface is the above-mentioned support surface 6 and an elevated portion 13 arranged on the side of the stirring bar magazine 3 opposite the outlet 8 when the extractor 5 is in the resting position.

[0036] The lowered portion 12 and the elevated portion 13 are mutually connected by a step portion extending parallel to the axis 9 and to the longitudinal axis 2' of the stirring bars 2 and having a height less than or at most equal to the thickness of the stirring bars 2.

[0037] The step between the descending portion 12 and the ascending portion 13 defines the abovementioned pusher 7 to push the stir stick 2 at the bottom of the stack 4 in response to the oscillation of the rotating member about the axis 9.

[0038] To this end, the rotating member 5 is operated by an electric actuator (not shown) connected preferably via an oscillating cam transmission (not shown) and electronically controlled by the electronic control unit of the beverage vending machine A to move the rotating member 5 between a retracted rest position (Fig. 1) Figure 4 ) in which the stir stick 2 rests on the support surface 6 and the step, i.e. the pusher 7, faces the stir stick 2 at the bottom of the stack 4, and an advanced extraction position (Fig. 2) Figure 5 ) in which the rotating member 5 is rotated forward, i.e. counterclockwise in Fig. 1, to such an extent that the pusher 7 is arranged outside the outlet 8 of the stir stick magazine 3. Figure 4

[0039] When moving between the retracted rest position and the advanced extraction position, the pusher 7 engages with the side of the stir stick 2 resting on the support surface 6 and pushes the stir stick in an extraction direction orthogonal to the hinge axis 9 and transversal to the longitudinal axis 2' through the outlet 8 of the stir stick magazine 3 until the stir stick is pushed out of the stack 4. When the advanced extraction position is reached, the rotating member 5 preferably returns to the rest position under the push of a spring.

[0040] During extraction of the stir stick 2, the stack 4 is supported by the ascending portion 13 of the extractor 5 and returns to rest on the descending portion 12 when the rotating member 5 returns to the rest position.

[0041] In the abovementioned embodiment, the extractor 5 thus comprises a descending portion 12 and an ascending portion 13 which move integrally as part of the rotating member.

[0042] In an alternative embodiment (not shown), the stack 4 rests on the upper surface of the ascending portion 13 instead of the upper surface of the descending portion 12 when the extractor 5 is in the rest position, and the extractor 5 is controlled to push out the stir stick 2 at the bottom of the stack 4 during the return stroke of the extractor 5 instead of during the forward stroke. Also in this embodiment, the descending portion 12 can be formed integrally with the ascending portion 13, so that it can move with the ascending portion or be stationary.

[0043] ​Regardless of the configuration of the extractor 5, the dimensions of the support surface 6 are designed to engage only with the central portion of the stirring rod 2 at the bottom of the stack 4, i.e. the width of the support surface 6 (measured in a direction parallel to the longitudinal axis 2' of the stirring rod 2) is designed so that the stirring rod 2 at the bottom of the stack 4 is in contact with the support surface 6 only at the central portion 2B of the stirring rod 2, and not along the entire length of the stirring rod.

[0044] With reference to Figure 4 and Figure 5 , the stirring rod dispenser 1 further comprises a shaped front housing 18 which surrounds the extractor 5 and defines a drop chute 19 to guide the extracted stirring rods 2 into the cup B.

[0045] The drop chute 19 has an inlet 20, adjacent to the head portion 11 of the extractor 5, and configured to receive the stirring rods 2 one at a time from the extractor 5, and an outlet 21, arranged below the inlet 20 and located near the upper end of the cup B, and configured to supply the stirring rods 2 into the cup B.

[0046] In particular, the shaped housing 18 comprises an essentially vertical, constant-section upper section 23 which delimits the inlet 20, and a downwardly tapering lower section 24 which delimits the outlet 21 and has a front wall 25 which slopes downward and toward the frame T, and which forms a guide chute which guides the stirring rods 2 toward the outlet 21.

[0047] With reference to Figure 4 and Figure 5 , the stirring rod dispenser 1 further comprises a movable member 26 which can be operated to temporarily stop each stirring rod 2 as it drops toward the outlet 21.

[0048] The movable member 26 is arranged within the drop chute 19 across the sections 23 and 24, and is suspended like a pendulum or a swing onto the head portion 11 of the extractor 5.

[0049] The movable member 26 is constituted by a shaped plate body and comprises an upper plate 27, the upper end of which is hinged to the head portion 11 to rotate about a horizontal hinge axis 29 which is stationary with respect to the head portion 11, and the lower end of which is firmly connected to a stop block 28.

[0050] The position of the hinge axis 29 on the head portion 11 is chosen so that, when the rotating member is in the retracted position, the distance between the hinge axis 29 and the attachment frame T, measured in a horizontal direction, is greater than the distance between the hinge axis 9 and the attachment frame T, measured in the same direction.

[0051] The stop block 28 is conveniently formed by a plate body having a thickness greater than that of the upper plate 27 and is arranged facing the wall 25 defining the guide chute.

[0052] Conveniently, the front portion of the head portion 11 is formed with a hook 30 and the upper plate 27 has two intermediate fulcrum pins inserted in the hook 30 through the front passage. Thereby, the movable member 26 is free to oscillate back and forth about the articulation axis 29. This enables the movable member 26 to rotate autonomously only during the movement of the rotating member 5, i.e. only under the sole action of its weight.

[0053] In particular, the inclination of the guide chute, the vertical dimension of the movable member 26 and the centre of gravity G of the latter are chosen so that when the extractor 5 is in its advanced extraction position, the movable member 26 is in an advanced operating position so that the stop block 28 is arranged to abut against the guide chute so as to temporarily stop the stirring rod 2 in the landing chute 19, and when the extractor 5 is in the retracted position or in a position close to the retracted position, the movable member 26 is in a non-operating or resting position in which it allows the stirring rod 2 to advance within the landing chute 19 towards the outlet 21.

[0054] From the foregoing it can be understood that the provision of the movable member 26 and its autonomous and automatic positioning only by the action of gravity enables the free landing of the stirring rod 2 present in the known solutions to be converted into a controlled landing in an extremely simple and safe manner. In other words, the presence of the movable member 26 enables the landing speed of the stirring rod 2 at a predetermined point of the landing path to be cancelled, which can be chosen by simply designing the dimensions of the geometric features of the movable member 26 and of the guide chute, and enables the impact intensity of the stirring rod within the cup B to be controlled.

[0055] Furthermore, the movable member 26 defines a further resting plane or abutment and control element of the position of the stirring rod 2. This further resting plane in particular defines a further guide of the stirring rod 2 which, together with an inclined plane, defines an intermediate variable cross-section passage during the movement of the movable member towards its resting position, which inevitably guides the stirring rod 2 accurately towards the outlet 21 and in the desired entry direction in the cup B.

[0056] Figure 6 The variant shown in the middle relates to a stirring rod dispenser 30 which, with the exception of some structural details, is identical to the dispenser 1 shown in the left-hand side of the figure. Figures 1 to 5 The dispenser 1 shown in the right-hand side of the figure differs from the dispenser 1 shown in the left-hand side of the figure only in some structural details and, where possible, the constituent parts are indicated with the same reference numerals as the corresponding parts of the dispenser 1.

[0057] The dispenser 30 comprises an extractor 31 which differs from the extractor 5 in that the head portion 11 comprises, in addition to the lowered portion 12 and the raised portion 13, an ejection lever 33 for moving the extracted stirring stick 2 away from the head portion 11 and pushing it towards the inlet 20 of the drop chute 19.

[0058] The ejection lever 33 is arranged in a partial housing seat 34 formed in the head portion 11 and between the lowered portion 12 and the raised portion 13.

[0059] The seat 34 is open upwards to communicate with the outside through two openings 35 and 36 separated from each other by a wall 37 formed integrally with the raised portion 13.

[0060] The ejection lever 33 has an intermediate portion 38 arranged below the wall 37 and hinged to the head portion 11 to oscillate about a fixed hinge axis 39 parallel to the axis 9 and to the longitudinal axis 2’.

[0061] The ejection lever 33 comprises two opposite ends, indicated by 41 and 42, shaped so that when one end is raised and located outside the head portion 11, the other end is lowered and inserted into the seat 34, and vice versa, as shown in Figures 7 to 10 .

[0062] In use, when the extractor 31 is in its retracted position, as shown in Figure 7 , the hinge axis 39 is located behind the box 4, i.e. on the other side of the outlet 8 of the box 4, and the portion 42 is kept in its lowered position by the stirring stick 2 resting on the lowered portion 12, so that the portion 41 protrudes upwards through the opening 35 and beyond the support surface of the raised portion 13, again as shown in Figure 7 .

[0063] On the other hand, when the extractor 32 is in its advanced position, as shown in Figure 8 , the hinge axis 39 is located in front of the box 4, and the portion 41 is pressed by the stack 4 of stirring sticks 2 inside the seat 34, the portion 42 is in the raised position and protrudes upwards through the opening 36 and beyond the support surface 6 of the lowered portion 12, again as shown in Figure 8 .

[0064] Figure 6 The variant shown in Figures 1 to 5 differs from the stirring stick dispenser 1 shown in

[0065] The stirring spatula dispenser 30 comprises an extractor 31 which differs from the extractor 5 in that the head portion 11 comprises, in addition to the descending portion 12 and the raised portion 13, a swing-rod ejection rod 33 for moving the extracted stirring spatula 2 away from the head portion 11 and pushing it towards the inlet 20 of the drop chute 19.

[0066] The ejection rod 33 is arranged in a partial housing seat 34 formed in the head portion 11 and between the descending portion 12 and the raised portion 13.

[0067] The seat 34 is open upwards to communicate with the outside through two openings 35 and 36 separated from each other by a wall 37 formed integrally with the raised portion 13.

[0068] The ejection rod 33 has an intermediate portion 38 arranged below the wall 37 and hinged to the head portion 11 to swing about a fixed hinge axis 39 parallel to the axis 9 and to the longitudinal axis 2'.

[0069] The ejection rod 33 also comprises two opposite end portions 41 and 42 shaped so that when one end portion is raised and located outside the head portion 11, the other end portion is lowered and inserted into the seat 34, and vice versa, as shown in Figures 7 to 10 .

[0070] During operation, when the extractor 31 is in the retracted position shown in Figure 7 , the hinge axis 39 is located behind the stirring rod box 4, i.e. on the other side of the outlet 8 of the stirring rod box 4, and the portion 42 is kept in the lowered position by the resting of the stirring spatula 2 on the descending portion 12, so that the portion 41 protrudes upwards through the opening 35 and beyond the resting plane of the raised portion 13, as shown in Figure 7 .

[0071] When the extractor 32 is in the advanced position shown in Figure 8 , the hinge axis 39 is located in front of the stirring rod box 4, the portion 41 is pressed by the stack 4 of stirring spatulas 2 in the seat 34, and the portion 42 is raised and protrudes upwards through the opening 36 and beyond the resting plane of the descending portion 12, as shown in Figure 8 .

[0072] As shown in Figure 6 and Figure 8 , the protrusion of the portion 42 through the opening 36 causes a pushing action from the bottom upwards on the lower surface of the extracted stirring spatula 2, so that the rear portion of the stirring spatula 2 extracted from the stack 4 is raised, the stirring spatula 2 is spaced apart from the descending portion 12 and from the step between the portions 12 and 13, and the stirring spatula 2 is subsequently pushed into the drop chute 19.

[0073] Regardless of the geometry of the stirring blade 2 and regardless of the material of which the stirring blade 2 is made, the provision of the ejection lever 33 always ensures the detachment of the stirring blade 2 extracted from the pile 4.

[0074] From the foregoing it is understood that in the stirring blade dispenser 1 the geometry and the dimensions of the movable member 26 and the relative position of the hinge axes 9 and 29 can be different from the one described by way of example, with the aim of varying or modifying the height of the interception point of the stirring blade 2 along the drop chute 19, in order to vary the profile of the advancing movement of the stirring blade.

[0075] In the stirring blade dispenser 30 the geometry of the ejection lever 33 can be different and the extractor 31 can be devoid of the movable member 26 or it can be provided with or associated with stop means different from the ones shown in the stirring blade dispenser 1.

[0076] In particular, in an embodiment not shown, the ejection lever 33 can be shaped so that when the extractor 31 is in the advanced position, the pivoting around the hinge axis 29 of the portion 42 which causes the lifting of the portion 42 is not the result of the lowering of the portion 41 under the thrust of the pile 4 of stirring blades 2, but it is caused by the action of a spring arranged below the portion 42.

[0077] Therefore, in this embodiment the shape and the dimensions of the portion 41 are not critical for the movement of the portion 42 or they can be completely absent. In this case, the ejection lever 33 comprises only the portion 42 which in turn can be hinged to oscillate around the hinge axis 29 or it can be mounted in the relative seat 36 to move elastically in the direction perpendicular to the support surface 6 between a normal raised position, which is the position assumed when the extractor 31 is in the advanced position, and a lowered position inside the seat 36, which is the position assumed when the extractor 31 is in the retracted position, and the portion 42 is weighted by the weight of the pile 4 of stirring blades 2.

Claims

1. A stir stick dispenser (1) for a beverage vending machine (A); the stir stick dispenser (1) comprising: - a fixed frame (T); - a stir bar magazine (3) carried by said fixed frame (T) and configured to contain a stack (4) of stir bars (2); and an extractor (31) arranged below said stir bar magazine (3) to extract stir bars (2) individually from said stack (4), and having a support surface (6) at the top which, when said extractor (31) is in a resting position, supports said stack (4) of stir bars (2) in said stir bar magazine (3); said extractor (31) is coupled to said fixed frame (T) and is motorized to move in an extraction direction transverse to the longitudinal axis (2') of the stir bars (2) between a retracted resting position in which said stack (4) rests on said support surface (6) and an advanced extraction position in which a stir bar (2) at the bottom of said stack (4) is extracted; characterized in that said stir bar dispenser comprises an ejection member carried by said extractor (31) to push the extracted stir bar (2) and movable with respect to said extractor (31) to move the stir bar (2) away from said extractor (31); wherein said ejection member comprises a pushing portion and is mounted to said extractor (31) to move between a lowered position and a raised position as said extractor (31) moves between the retracted position and the advanced position, so that the extracted stir bar (2) is disengaged from said support surface (6) and moved away from said support surface, said lowered position being the one assumed when said extractor (31) is in said retracted position and said pushing portion does not protrude beyond said support surface (6), said raised position being the one assumed when said extractor (31) is in said advanced position and said pushing portion protrudes beyond said support surface (6); wherein said ejection member is configured so that, when said extractor (31) is in said retracted position, said pushing portion of said ejection member is kept in said lowered position by the weight of said stack (4) of stir bars (2).

2. The stir bar racker (1) according to claim 1, wherein Said ejection member comprises a swing lever (33) having an intermediate portion (38) hinged to said extractor (31) to rotate freely in two opposite directions with respect to a hinge axis (39) fixed with respect to said extractor (31); said swing lever (33) further comprises two opposite end portions (41, 42) arranged on opposite sides of said hinge axis (39) and configured, in use, one (41) to cooperate with a stir bar (2) at the bottom of said stack (4) and the other (42) to cooperate with a stir bar (2) extracted from said stack (4) of stir bars (2); wherein one (42) of said end portions defines said pushing portion and the other (41) defines an actuation portion for actuating said pushing portion.

3. The stir bar racker (1) according to claim 2, wherein Said hinge axis (39) is a horizontal axis.

4. The stir bar racker (1) according to claim 2, wherein Said extractor (31) is hinged to said frame (T) to oscillate back and forth about a further hinge axis (9) fixed with respect to said frame (T) and parallel to said hinge axis (39); in said extraction direction, said hinge axis (39) is located behind said stirring rod box (3) when said extractor (31) is in said retracted position and in front of said stirring rod box (3) when said extractor (31) is in said advanced position.

5. The stir bar racker (1) according to claim 2, wherein, Said extractor (31) is delimited at the top by said support surface (6) for stirring rods (2) and said oscillating lever (33) is movable about said hinge axis (39) between two extreme end-of-travel angular positions, in each of which one of said end portions (41, 42) extends beyond said support surface (6) for stirring rods (2) and the other extends tangentially to or below said support surface (6).

6. The stir stick dispenser (1) according to claim 2, wherein, Said extractor (31) comprises an upper end portion (11) delimited at the top by said support surface (6) for stirring rods (2) and a housing seat (34) formed in said upper end portion (11); said oscillating lever (33) is at least partially housed in said seat (34); said seat (34) communicates with the outside via a pair of through openings (35, 36) formed through said support surface (6) and each of which is crossed by a respective end portion (41, 42) of said oscillating lever (33). Said hinge axis (39) is a horizontal axis. Said extractor (31) is hinged to said frame (T) to oscillate back and forth about a further hinge axis (9) fixed with respect to said frame (T) and parallel to said hinge axis (39); in said extraction direction, said hinge axis (39) is located behind said stirring rod box (3) when said extractor (31) is in said retracted position and in front of said stirring rod box (3) when said extractor (31) is in said advanced position. Said extractor (31) is delimited at the top by said support surface (6) for stirring rods (2) and said oscillating lever (33) is movable about said hinge axis (39) between two extreme end-of-travel angular positions, in each of which one of said end portions (41, 42) extends beyond said support surface (6) for stirring rods (2) and the other extends tangentially to or below said support surface (6). Said extractor (31) comprises an upper end portion (11) delimited at the top by said support surface (6) for stirring rods (2) and a housing seat (34) formed in said upper end portion (11); said oscillating lever (33) is at least partially housed in said seat (34); said seat (34) communicates with the outside via a pair of through openings (35, 36) formed through said support surface (6) and each of which is crossed by a respective end portion (41, 42) of said oscillating lever (33).

Images