CENTERING UNIT WITH ANTI-ROTATION GROUP

Abstract

The present invention relates to a centering unit (10) comprising a housing body (11) in which a centering rod (13) is received at least partially in a linearly movable manner along an actuating axis (A) between a first minimum extraction position from the housing body (11) and a second maximum extraction position from the housing body (11); and an anti-rotation group (40) configured to prevent rotation of the centering rod (13) about the actuating axis (A) during its movement between the first and second positions;characterized in that the anti-rotation group (40) comprises a sliding block (41) which is fixedly connected to the centering rod (13) and a guide (42) which is fixedly connected to the housing body (11), wherein the sliding block (41) is fixed to slide along the guide (42) in a direction parallel to the actuating axis (A) by means of the interposition of at least one pair of adjacent rollers (46) whose respective roller axes are arranged in parallel planes and transversely to each other.

Description

Technical field

[0001] The present invention relates generally to a centering unit with an anti-rotation group. In particular, the present invention relates to centering units that are typically used in the field of sheet metal processing, for example for the construction of motor vehicle bodies. State of the art

[0002] In the construction of motor vehicle bodies, it is well known to use, for example, centering units to create special references that ensure the correct positioning of sheet metal on the processing machines.

[0003] For this purpose, known centering units are designed to move a centering rod linearly along an actuating axis between two end positions: a first rest position in which the centering rod is largely retracted into the body of the centering unit, and a second operating position in which the centering rod protrudes more from the body of the centering unit. The centering units are generally controlled by a pneumatic or electric actuator that acts on an element movable axially between the two end positions. This actuator then acts on the centering rod to move it between the rest position and the operating position.

[0004] To implement an accurate positional reference when the rod is in its operating position, it can, for example, have an asymmetrical shape at its free end, creating a contact surface. With such a configuration, it is essential that the centering rod reaches the operating position without rotating around its axis of actuation. Otherwise, the contact surface would provide an inaccurate reference for the desired positioning.

[0005] Known centering units implement various solutions to maintain the angular position of the centering rod.

[0006] Document EP 1132628 describes the use of a connecting pin between the actuator piston and the centering rod. The pin extends offset from the axis, parallel to the actuation axis.

[0007] Document US 8 366 085 describes the use of a pair of rollers arranged in diametrically opposite positions with respect to the rod, each of which runs along a respective longitudinal track parallel to the actuating axis.

[0008] Documents DE102018003877 and EP 1123779 describe the use of a pin that is connected to the centering rod and is fixed in an axial guide parallel to the actuating axis to slide.

[0009] Known solutions do not always offer sufficient accuracy in maintaining the angular position of the centering rod. Some solutions are even unable to provide the same reliability with respect to both possible rotation directions of the centering rod. Furthermore, known solutions can lead to significant friction when the rod slides between the rest position and the operating position, and vice versa, resulting in the dissipation of some of the actuating thrust provided by the actuator.

[0010] To facilitate the maintenance of centering units, it is particularly important to design the unit so that the actuator, whether pneumatic or electric, can be replaced. Replacing the actuator can be complex and difficult, especially in electrically driven units. This is because, due to the type of drives traditionally used in electrically driven centering units, the action is transmitted via a rotating rod, requiring special gears to convert the rotational motion into a linear translation of the centering rod. The structural complexity of such actuators and the number of gears involved generally make it difficult to design a connection interface that facilitates the disassembly and reassembly of the actuator.Furthermore, to ensure maximum operating efficiency, the assembly and disassembly of the actuator must not alter the coaxial arrangement between the stator and rotor. Subject matter and summary of the invention

[0011] Against this background, the present invention aims to create a centering unit that is able to overcome the disadvantages of the prior art.

[0012] Within the context of this problem, it is an object of the present invention to provide a centering unit that is able to effectively prevent rotation of the centering rod around the actuating axis without generating significant friction that could lead to a dissipation of a large part of the actuating thrust supplied to the centering unit.

[0013] Another object of the present invention is to create a centering unit that can effectively counteract rotation of the centering rod in both directions of rotation.

[0014] Another objective of the present invention is to create a centering unit that makes it possible to connect and remove an actuator without affecting its performance and wear.

[0015] According to a first aspect, the invention thus relates to a centering unit with a housing body in which a centering rod is received at least partially in a linearly movable manner along an actuating axis between a first minimum extraction position from the housing body and a second maximum extraction position from the housing body; and an anti-rotation group configured to prevent rotation of the centering rod about the actuating axis during its movement between the first and second positions.

[0016] According to the present invention, the anti-rotation group comprises a sliding block that is fixedly connected to the centering rod and a guide that is fixedly connected to the housing body, wherein the sliding block is fixed to slide along the guide in a direction parallel to the actuating axis by means of the interposition of at least one pair of adjacent rollers, the respective roller axes of which are arranged in parallel planes and transversely to each other.

[0017] The applicant has determined that the use of the special anti-rotation group, which is equipped with a sliding block and a guide coupled by rollers, effectively prevents rotation of the centering rod around the actuating axis while generating only minimal or essentially zero friction. This allows for maximum utilization of the actuating thrust provided by the actuator in question.

[0018] In particular, each roller of the pair of adjacent rollers, whose respective roller axes are arranged in parallel planes and transversely to each other, is able to counteract torsion in a specific direction of rotation, thereby effectively preventing rotation of the rod in both directions.

[0019] The present invention may have at least one of the following preferred features; the latter may in particular be combined arbitrarily to meet specific application needs.

[0020] Preferably, the sliding block is coupled to the guide by at least a plurality of adjacent rollers, the respective roller axes of which are contained in parallel planes, wherein the roller axes are alternately transverse to the adjacent roller axes.

[0021] In one embodiment of the invention, the rollers of the at least one pair of rollers are fixed, each rotating about its own roller axis within a longitudinal seat which extends parallel to the actuating axis, wherein the longitudinal seat is defined by a pair of longitudinal half-seats, wherein a first half-seat of the pair of longitudinal half-seats is made on a wall of the sliding block which faces the guide, and a second half-seat of the pair of half-seats is made on a wall of the guide which faces the block.

[0022] Preferably, each longitudinal half-seat has a V-shaped or substantially triangular cross-section that is open on one side.

[0023] In one variant of the invention, at least two connecting elements project transversely from the block towards the interior of the housing body, designed to engage in a group of corresponding housing seats that are present on the sleeve of the centering rod.

[0024] Alternatively, the sliding block is integrally formed with the centering rod.

[0025] Preferably, at least two groups of housing seats for receiving the connecting elements are provided on the sleeve of the centering rod, each group of housing seats comprising a plurality of seats aligned along a direction parallel to the actuating axis, each group of housing seats being provided on the sleeve of the centering rod in a different angular position.

[0026] In one embodiment of the invention, the centering unit comprises an actuator which is provided with an actuator body which is connected to the housing body and is configured to act on a control rod which in turn is fixed to the centering rod, wherein the actuator is configured to move the control rod linearly along a control axis between two end positions, a first position of maximum insertion into the actuator body and a second position of minimum insertion into the actuator body.

[0027] Preferably, the actuator body is detachably connected to the housing body at its bottom wall.

[0028] The applicant has recognized that the detachable connection between the actuator body and the housing body facilitates the maintenance and replacement of the electric actuator.

[0029] In one variant of the invention, a head wall of the actuator body, acting as a connection interface with the housing body, and a bottom wall of the housing body, acting as a connection interface with the actuator body, are shaped complementarily in order to implement a relative positioning guide between the actuator body and the housing body in such a way that the drive axis essentially coincides with the actuator control axis.

[0030] The applicant has recognized that the special shaping of the head wall of the actuator body, which acts as a connection interface with the housing body, and the bottom wall of the housing body, which acts as a connection interface with the actuator body, in order to implement a relative positioning guide between the actuator body and the housing body, ensures precise positioning with respect to the actuation axis of the closing device which coincides with the rotation axis of the magnetic rotor, thus minimizing the friction involved.

[0031] In one variant of the invention, the actuator body has a guide and centering projection that extends at least partially from the head wall of the actuator body, which acts as a connecting interface with the housing body, to the outside of the actuator body.

[0032] Accordingly, the housing body has a guide opening produced on the bottom wall of the housing body, which acts as a connection interface with the actuator body, wherein the guide opening is designed to receive and interact with the guide and centering projection in order to implement the relative positioning guide.

[0033] Advantageously, the presence of the guide and centering projection on the actuator body facilitates centered and coaxial positioning relative to the housing of the locking device during assembly. This is further supported by the presence of a guide opening on the bottom wall of the housing body, which is designed to receive the guide and centering projection and to interact with it to guide the relative positioning between the actuator body and the housing body.

[0034] Preferably, the guide opening has at least one part with a section complementary to at least one section of the guide and centering projection transversely to the actuation axis.

[0035] Preferably, at least one complementary section of the guide mouth can be coupled to the guide and centering projection by interference and / or essentially without play.

[0036] Advantageously, an interference fit or an essentially zero clearance between the guide mouth and the guide and centering projection ensures high precision in the relative positioning between the housing body and the actuator body, in order to guarantee substantial coaxiality between the actuating axis of the locking device and the actuator drive axis.

[0037] In one variant of the invention, the actuator is of an electrical type and comprises a cylindrical electromagnetic stator and a cylindrical hollow magnetic rotor inside and coaxial to the electromagnetic stator, wherein the actuator control axis is a rotation axis of the hollow magnetic rotor.

[0038] Preferably, a first end of the magnetic rotor protrudes from the actuator body at the guide and centering projection.

[0039] Preferably, the guide opening is shaped to receive the first projecting end in a rotationally movable manner.

[0040] Preferably, the guide and centering projection has an extension surrounding the protruding end of the magnetic rotor, more preferably an extension with axial symmetry with respect to the actuating axis.

[0041] In one variant of the invention, the magnetic rotor is fixed to the actuator body so as to be rotatable around the control axis of the electric actuator by means of an intermediate pair of bearings.

[0042] Preferably, an end wall of the actuator body defines a housing seat for a first bearing of the pair of bearings, which faces the interior of the actuator body.

[0043] Preferably, the bearings of the pair of bearings are arranged substantially at or near a head end and a lower end of the actuator body.

[0044] Preferably, the head wall of the actuator body is limited by a head cover of the actuator body.

[0045] Furthermore, the housing seat of the first bearing is preferably manufactured on the guide and centering projection.

[0046] This makes it advantageously possible to design the actuator in a particularly compact form.

[0047] In one embodiment of the invention, the control rod is provided with a thread and engages in a nut that is firmly connected to the magnetic rotor, wherein the nut has a thread which is designed internally such that it engages with a thread of the control rod, so that a rotation of the nut leads to a translation of the threaded rod.

[0048] Preferably, the nut is substantially completely contained within a defined volume inside the hollow magnetic rotor, more preferably at its first termination, which projects from the actuator body.

[0049] Advantageously, the internal arrangement of the nut, which is firmly connected and / or integrally integrated with the hollow magnetic rotor, facilitates the implementation of a strictly coaxial rotor / nut arrangement with respect to the stator. This minimizes friction and allows for maximum utilization of the torque offered by the electric actuator. In fact, the nut's position inside the rotor prevents any micro-dislocation of the nut that might occur during assembly of the actuator to the housing.

[0050] Furthermore, due to the internal arrangement of the nut in relation to the hollow magnetic rotor, it is also possible to support the rotor using the bearing pair.

[0051] In one variant of the invention, the bottom wall of the housing body comprises a pair of screw seats arranged symmetrically according to a central symmetry with respect to an intersection of the actuating axis on the bottom wall.

[0052] Similarly, the actuator body comprises a pair of screws that pass through it parallel to the actuating axis and are arranged in opposite angular positions with respect to this actuating axis.

[0053] Advantageously, such symmetrical arrangements of the screw seats and screws allow the electric actuator to be mounted on the housing body either with a first orientation or with a second orientation rotated by 180° relative to the first, thus enabling the drive electronics to be accommodated on a first or second side with respect to the drive body.

[0054] Preferably, the control rod thread is designed to allow the reversibility of the rotation of the control rod in the absence of any command mediated by the electrical actuator.

[0055] Conveniently, the suitable thread, which allows reversible rotation of the control rod, facilitates the manual opening operations of the actuating unit in addition to the assembly operations of the electric actuator on the housing body.

[0056] In one variant of the invention, the first end of the hollow magnetic rotor is manufactured as a crown wheel with a conical shape.

[0057] Preferably, the unit also includes manual drive means designed to impart rotation to the crown wheel end of the magnetic rotor.

[0058] Advantageously, the shape of the first termination of the crown wheel rotor and the presence of manual drive means designed to impart rotation to this crown wheel allow manual intervention directly on the rotor, thus facilitating the disassembly and reassembly of the electric actuator to the housing body, providing a perfectly coaxial effect on the actuation and rotation axes.

[0059] Further preferably, the first manual drive means comprise at least one toothed element which is received in the housing body near a bottom wall of the housing body, wherein the toothed element is arranged in the housing body such that it is rotatable about an axis transverse to the actuation axis and translationally movable along this transverse axis in order to selectively engage the crown gear end, wherein the toothed element is designed such that, when engaged with the crown gear end, a rotation imparted to the toothed element about the transverse axis causes a rotation of the magnetic rotor about the rotation axis of the electric actuator.

[0060] Preferably, the gearing element has a toothed conical head.

[0061] Preferably, an elastic restoring means acts on at least one toothed element to return the toothed element to a non-engagement position away from the crown gear end when it is not forced to assume the engagement position.

[0062] The special design of the manual drive mechanism allows for easy and convenient operation of the rotor, potentially using conventional tools such as an electric screwdriver or similar implement. The rotor is actuated by applying force to the toothed element transversely to the actuating axis, engaging it and imparting rotation. Advantageously, after the force is released, the toothed element automatically returns to a rest position, free of engagement with the rotor, thanks to its elastic return mechanism.

[0063] In one variant of the invention, the bearings of the bearing pair are both radial and axial bearings.

[0064] Preferably, the bearings of the pair of bearings comprise a plurality of balls which are received in a crown-shaped seat, the seat forming both an upper and a lower abutment against which the balls bear.

[0065] Advantageously, the bearings in this way allow the magnetic rotor to rotate while keeping its position perfectly coaxial to the actuating axis and counteracting the axial forces that occur, especially when the drive rod reaches its end positions.

[0066] In one variant of the invention, the electromagnetic stator comprises a plurality of coils with a winding axis arranged radially to the axis of rotation, and the hollow cylindrical magnet rotor comprises a plurality of permanent magnets arranged on a rotor shell parallel to the axis of rotation and with alternating polarity with respect to neighboring magnets.

[0067] In one variant of the invention, the unit comprises an encoder which is associated with and configured to monitor the instantaneous position of the rod as a function of the number of revolutions performed by the rotor. Brief description of the drawings

[0068] Further features and advantages of the present invention will become clearer from the following detailed description of some preferred embodiments thereof, which are made with reference to the accompanying drawings.

[0069] The different features in the individual configurations can be combined as preferred, according to the preceding description, should specific advantages result from a particular combination.

[0070] In these drawings, - is Fig. 1 a perspective view of a centering unit according to a first preferred embodiment of the present invention; - is Fig. 2 a sectional view of the centering unit in Fig. 1; - are Fig. 2a and Fig. 2b Sectional views along the section lines BB and CC in Fig. 2; - are Fig. 3 and Fig. 3a a partial exploded view of the centering unit in Fig. 1 and an enlarged detail thereof; - is Fig. 4 a perspective view of the centering unit of Fig. 1 in a partially disassembled configuration; and - is Fig. 5 a perspective view from below of the housing body of the centering unit in 1 in a disassembled configuration of the electric actuator; - are Fig. 6a and Fig. 6b Partial sectional views of the centering unit according to a second preferred embodiment, in which the actuating electronics are mounted on a first or second side; - is Fig. 7 a sectional view of a centering unit according to a third preferred embodiment of the present invention; and - are Fig. 8, Fig. 8a, Fig. 9 and Fig. 9a Partial section views along the section lines aa and bb in Fig. 7 or enlarged details. Detailed description of the invention

[0071] To illustrate the drawings, the same numbers or symbols are used in the following description to identify design elements with the same function. Furthermore, for clarity, certain references may not be repeated in all drawings.

[0072] While the invention is suitable for various modifications and alternative designs, certain preferred embodiments are shown in the drawings and are described in detail below. It is understood in any case that the invention is not intended to be limited to the specific embodiment shown, but rather, on the contrary, the invention is intended to cover all modifications, alternative and equivalent designs that fall within the scope of the invention, as defined in the claims.

[0073] The use of "for example," "etc.," and "or" does not indicate exclusive alternatives without limitation unless otherwise stated. The use of "includes" and "includes" means "includes or includes, but is not limited to," unless otherwise stated.

[0074] With reference to the Fig. Figures 1-5 show a first preferred embodiment of a centering unit according to the present invention, which is collectively designated by the number 10.

[0075] The centering unit 10 comprises a housing body 11 in which a centering rod 13 is at least partially movably mounted. The centering rod 13 is linearly movable along an actuation axis A between two end positions: a first minimum extraction position from the housing body 11 and a second maximum extraction position from the housing body 11.

[0076] The centering unit 10 further comprises an actuator 20, which is provided with an actuator body 23, which is detachably connected to the housing body 11 on a bottom wall 11c of the housing body 11.

[0077] The actuator 20 is configured to act on a control rod 14, which in turn is fixed to the centering rod 13. In particular, the actuator 20 is configured to move the control rod 14 linearly along a control axis, which in particular coincides with the actuating axis A, between two end positions, a first position of maximum insertion into the actuator body 23 and a second position of minimum insertion into the actuator body 23.

[0078] To prevent rotation of the centering rod 13 about the actuating axis A, the centering rod 13 is secured by an anti-rotation group 40, which is located in the Fig. 2a, Fig. 2b, Fig. 3 and Fig. The anti-rotation group 40, as shown in detail in Figure 3a, is slidably coupled to the housing body 11. It comprises a sliding block 41 fixedly connected to the centering rod 13 and a guide 42 fixedly connected to the housing body 11, the sliding block 41 being slidably fixed within the guide 42.

[0079] In the first embodiment shown, the centering rod 13 is connected to the sliding block 41 by several fastening means 45, such as screws, which engage in the sliding block 41 and fit into corresponding threaded receptacles 45a formed in the centering rod 13. Furthermore, at least two connecting elements 43 are provided, which project transversely from the sliding block 41 towards the inside of the housing body 11 in the direction of the actuating axis A and are spaced apart from each other along a direction parallel to the actuating axis A. The connecting elements 43 can be designed, for example, as pivot pins, pins, or plates, or their equivalents.

[0080] The connecting elements 43 are configured to engage in a group of respective seats 44 accessible from the sleeve of the centering rod 13 and extending towards the interior of the centering rod 13 in a direction transverse to the direction of the actuating axis A. The seats 44 of the connecting elements are also spaced apart from one another in a direction parallel to the actuating axis A, specifically by the same distance as the connecting elements 43 are spaced apart, thus enabling each of the elements 43 to engage in a respective seat 44. In this way, the connection between the sliding block 41 and the centering rod 13 is stronger than any torque to which the rod 13 is subjected.

[0081] In particular, the centering rod 13 comprises at least two groups of seats 44 complementary to the connecting elements 43. Preferably, each group of seats 44 is provided on the sleeve of the centering rod 13 at a different angular position, such as a first position rotated by 90° about the actuating axis A with respect to a second position. In this way, the centering rod 13 can be coupled to the sliding block 41 in at least two predefined orientations, e.g., a first orientation in which the centering rod 13 is rotated by 90° about the actuating axis A with respect to a second orientation. Correspondingly, there are also at least two groups of threaded housings 45a for the engagement of the fastening elements 45 in at least two predefined orientations.

[0082] The sliding block 41 is slidably coupled to the guide 42 along a direction parallel to the actuating axis A by the interposition of at least one pair of rollers 46.

[0083] Preferably, the sliding block 41 is formed by the interposition of at least a plurality of rollers 46 or, as in Fig. 3a shown in detail, coupled to the guide 42 by the interposition of two multiples of rollers 46.

[0084] In the first embodiment of the invention, the sliding block 41 is coupled to the guide 42 by means of two pluralitys of rollers 46, and the guide 42 comprises a pair of half-guides 42a. In each plurality of rollers, the rollers 46 are arranged side by side with their respective roller axes in parallel planes, the roller axes being alternately transverse, e.g. orthogonal, to the adjacent roller axes.

[0085] The rollers of each of the plurality of rollers 46 are each rotatably fixed about their own roller axis within a respective longitudinal seat 47, which extends parallel to the actuating axis A. Each longitudinal seat 47 is defined by a pair of longitudinal half-seats 47a, 47b having a V-shaped or substantially triangular cross-section open on one side, wherein a first half-seat 47a of the pair of half-seats is formed on a respective side wall of the sliding block 41 facing the guide 42, and a second half-seat 47b of the pair of half-seats is formed on a respective inner wall of the guide 42 facing the sliding block 41.

[0086] In the illustrated embodiment, the half-guide 42a of the guide 42 defines a respective longitudinal seat 47 with the sliding block 41.

[0087] The actuator 20 is generally of a pneumatic or electric type. In the specific case of the illustrated embodiment, the actuator 20 is of an electric type. However, the principles of the present invention are equivalently applicable to centering units that are operated by means of a pneumatic actuator.

[0088] The electric actuator 20 is of the hollow shaft type, such as a torque motor, and comprises a cylindrical electromagnetic stator 21, which is fixed to the actuator body 23. The electromagnetic stator 21 interacts with a corresponding hollow magnetic rotor 24, which therefore also has a cylindrical shape and is arranged coaxially within the electromagnetic stator 21. The magnetic rotor 24 is designed to rotate about the control axis of the electric actuator 20. The electromagnetic stator 21 is driven by drive electronics 30, which are mounted on the side of the actuator body 23.

[0089] Preferably, the electromagnetic stator 21 comprises a plurality of coils (not shown) with a winding axis radial to the actuating axis A. The hollow magnetic rotor 24 comprises a plurality of permanent magnets (not shown) with an elongated shape, for example of the brick or parallelepiped type, arranged on the cylindrical sleeve, parallel to the actuating axis A and with alternating polarity with respect to the adjacent magnets.

[0090] The magnetic rotor 24 is axially fixed to the actuator body 23 by the interposition of a pair of bearings 31, 32, which are arranged substantially at or near a head end and a lower end of the body 23. Each end of the actuator body 23 is preferably closed by a respective head cover 25 and a lower cover 27, wherein the head cover 25 defines a head wall 25b that bounds the actuator body 23 outwards at the top, while the lower cover 27 defines a bottom wall that bounds the actuator body 23 outwards at the bottom.

[0091] Furthermore, a nut 22 is provided, which is fixed to the hollow magnetic rotor 24. The nut 22 has an internal thread designed to engage with the control rod 14, so that a rotation of the nut 22, induced by the cylindrical rotor 24, causes a translation of the threaded control rod 14. For this purpose, the control rod 14 has a thread on its outer sleeve.

[0092] Advantageously, the nut 22 is accommodated inside the hollow magnetic rotor 24, preferably in such a way that it remains substantially completely enclosed in the hollow magnetic rotor 24.

[0093] In the illustrated embodiment, the nut 22 is arranged inside the hollow magnetic rotor 24, at the first end 24a of which projects from the actuator body 23 and is held inside the rotor 24 by a ring nut 26. In particular, the first end 24a of the rotor 24 projects from the actuator body 23 onto the head cap 25, which closes this body 23 at the top and acts as a connection interface to the housing body 11.

[0094] In a possible variant of the invention not shown, the hollow magnetic rotor 24 has an internal thread which is designed to engage with the threaded control rod 14 and itself acts as a nut.

[0095] The threaded control rod 14 is permanently and coaxially connected to a first end of the centering rod 13. In alternative embodiments not shown, the control rod 14 is formed integrally with the centering rod 13.

[0096] The housing body 11 and the actuator body 23 are advantageously shaped in a complementary manner to form a centering guide on each other, thereby facilitating the mounting or replacement of the electrical actuator 20 on the body 11.

[0097] To this end, as is clearly shown in Fig. As can be seen in Figure 4, the head wall 25b of the actuator body 23 has at least one guide and centering projection 25a extending towards the outside of the actuator body 23. Preferably, the guide and centering projection 25a has an extension with axial symmetry with respect to the actuating axis A, such as a cylindrical extension centered on the actuating axis A, or an extension with concentric cylinders of different diameters centered on the actuating axis A. The guide and centering projection 25a extends around the projecting end 24a of the magnetic rotor 24, preferably substantially in contact with it.

[0098] In a complementary manner, the housing body 11 has a guide opening 37 (in Fig. (5 shown) on its bottom wall 11c, which acts as a connection interface with the actuator body 23. The guide opening 37 is shaped to accommodate both the first projecting end 24a of the magnetic rotor 24 and at least a portion of the guide and centering projection 25a. In particular, the first projecting end 24a of the magnetic rotor 24 can be received in the guide opening 37—and is received in an assembled configuration—without contact, allowing it to rotate freely. In contrast, the guide and centering projection 25a can be received in the guide opening 37—and is received in an assembled configuration—with interference or substantially without play, to act as an substantially precise centering element between the actuating axis A and the actuator control axis 20.

[0099] In the illustrated first embodiment, the head cover 25 advantageously defines a housing seat for a first bearing 31 of the pair of bearings 31, 32. In particular, the housing seat of the first bearing 31 is advantageously arranged on the guide and centering projection 25a, but is located on the opposite side with respect to the head wall 25b, which is externally bounded by the cover 25, i.e., it faces the interior of the actuator body 23.

[0100] The first bearing 31 is therefore located essentially near the first end 24a of the magnet rotor 24. The first bearing 31 is received in the seat defined by the head cover 25 by the interposition of a seal 38 to increase the degree of insulation and protection of the actuator body 23.

[0101] In a similar manner to the first bearing 31, a second bearing 32 of the pair bearings 31, 32 is arranged at a second end 24b of the magnet rotor 24 opposite the first end 24a, essentially at the lower end of the actuator body 23.

[0102] Preferably, both the first 31 and the second 32 bearings are of the radial and axial bearing type. In the illustrated embodiment, the bearings 31, 32 comprise a plurality of balls 33 which are received in a seat 34 shaped like a crown, forming both an upper 35 and a lower abutment 36 against which the balls 33 bear.

[0103] The lower cover 27 of the actuator body 23 carries an encoder 28 for monitoring the instantaneous position of the control rod 14 as a function of the number of revolutions performed by the rotor 24 and detected by the encoder 28. For this purpose, the magnetic rotor 24 carries a magnet 29 at its second end 24b opposite the first 24a.

[0104] The centering unit 10 further comprises manual means 16 for driving the rotor 24. For this purpose, the first end 24a of the rotor 24, which projects from the actuator body 23, is manufactured in the form of a crown gear with a conical shape, and the manual drive means 16 are designed to impart rotation to the crown gear end 24a of the magnetic rotor 24.

[0105] In particular, in the embodiment shown, the manual drive means 16 comprise a toothed element 16a which is received in the body 11 near its lower wall 11c.

[0106] The toothed element 16a is received in the housing body 11 such that one of its first ends terminates substantially at the toothed crown element 24a and a second end of the same points laterally away from an opening 11b provided in the housing body 11. At its first end, the at least one toothed element 16a is provided with a toothed conical head, which is designed to engage with the toothed crown termination 24a of the rotor 24.

[0107] The toothed element 16a is movably arranged in the housing body 11 along a direction transverse to the actuating axis A between a non-engagement position with the toothed crown end 24a and an engagement position with the toothed crown end 24a. In the engagement position, a rotation of the toothed element 16a about the transverse axis causes a rotation of the rotor 24 about the actuating axis A and consequently a translation of the control rod 14 along this actuating axis A.

[0108] A corresponding elastic restoring device (not shown) acts on the toothed element 16a to bring the toothed element 16a into the non-engagement position from the rotor 24 when it is not forced to enter the engagement position.

[0109] Fig. Figure 4 shows the centering unit 10 according to the first embodiment, which is disassembled, i.e., with the electric actuator 20 removed from the housing body 11, e.g., for replacement or maintenance of the electric actuator 20. As can be seen in this figure, the control rod 14 can be removed from the electric actuator 20 while remaining fixed to the housing body 11. Removal of the rod 14 is achieved by rotating the magnetic rotor 24 and thereby determining the relative translation between the rod 14 and the rotor 24. Such a rotation can be easily transmitted by means of the toothed element 16a once it is engaged with the toothed crown end 24a of the rotor 24.

[0110] Mounting the electric actuator 20 on the housing body 11 also requires rotating the magnetic rotor 24. Once the maximum insertion position is reached, the projection 25a acts as a guide and centering roller between the housing body 11 and the electric actuator 20, allowing the two elements to be fixed to each other in a configuration of perfect alignment between the control rod 14 and the control axis of the actuator 20.

[0111] According to a second embodiment of the invention, the electric actuator 20 can be mounted on the housing body 11 in two different configurations, i.e., with the drive electronics 30 arranged on a first side or on a second side opposite the first side in relation to the drive body 11, as shown in Fig. 6a and Fig. 6b shown. For this purpose, the actuating body 11 comprises two screw seats 11d arranged symmetrically on its bottom wall 11c according to a central symmetry with respect to an intersection of the actuating axis A on the bottom wall 11c. This allows a pair of screws 27b to be screwed into the screw seats 11d, which run parallel to the actuating axis A through the actuating body 23 and are arranged in positions equidistant from this actuating axis A, but offset from it by 180°.

[0112] The Fig. 7, Fig. 8, Fig. 8a, Fig. 9 and Fig. Figure 9a shows a third embodiment of the invention of a centering unit 10, in which the centering rod 13 is slidably coupled to the housing body 11 by means of an anti-rotation group 40, which has a sliding block 41 fixedly connected to the centering rod 13 and a guide 42 fixedly connected to the housing body 11, wherein the sliding block 41 is slidably fixed along the guide 42.

[0113] In particular, the sliding block 41 is coupled to the guide 42 by means of the interposition of a single plurality of rollers 46, e.g. a pair of rollers 46 which are arranged side by side with their respective roller axes in parallel planes, wherein the roller axes are alternately transverse, e.g. orthogonal, to the adjacent roller axes, as can be seen from a comparison of the Fig. 8a and Fig. 9a is evident.

[0114] In this case, too, the rollers of the multitude of rollers 46 are each fixed to rotate around their own roller axis within a longitudinal seat 47, which extends parallel to the actuation axis A.

[0115] As in the Fig. 8 and Fig. As shown in Figure 9, the longitudinal seat 47 is defined by a pair of longitudinal half-seats 47a, 47b having a V-shaped or substantially triangular cross-section open on one side, wherein a first half-seat 47a of the pair of half-seats is made on a side wall of the sliding block 41 facing the guide 42, and a second half-seat 47b of the pair of half-seats is made on a wall of the guide 42 facing the sliding block 41.

[0116] In the third embodiment of the invention, the guide 42 is arranged between a wall of the housing body 11 and the sliding block 41, while the sliding block 41 is arranged between the guide 42 and the centering rod 13 to which it is fixed. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 1132628

[0006] US 8 366 085

[0007] DE 102018003877

[0008] EP 1123779

[0008]

Claims

[1] Centering unit (10) comprising -a housing body (11) in which a centering rod (13) is received at least partially in a linearly movable manner along an actuating axis (A) between a first minimum extraction position from the housing body (11) and a second maximum extraction position from the housing body (11); and -an anti-rotation group (40) designed to prevent rotation of the centering rod (13) about the actuating axis (A) during its movement between the first and second positions; characterized by, that the anti-rotation group (40) comprises a sliding block (41) which is fixedly connected to the centering rod (13) and a guide (42) which is fixedly connected to the housing body (11), wherein the sliding block (41) is set to slide along the guide (42) in a direction parallel to the actuating axis (A) by means of the interposition of at least one pair of adjacent rollers (46) whose respective roller axes are arranged in parallel planes and transversely to each other. [2] Centering unit (10) according to claim 1, wherein the sliding block (41) is coupled to the guide (42) by at least a plurality of adjacent rollers (46) whose respective roller axes are contained in parallel planes, wherein the roller axes are alternately transverse to the adjacent roller axes. [3] Centering unit (10) according to claim 1 or 2, wherein the rollers of the at least one pair of rollers (46) are fixed to rotate about their own roller axis within a longitudinal seat (47) extending parallel to the actuating axis (A), wherein the longitudinal seat (47) is defined by a pair of longitudinal half-seats (47a, 47b), wherein a first half-seat (47a) of the pair of longitudinal half-seats is made on a wall of the sliding block (41) facing the guide (42), and a second half-seat (47b) of the pair of half-seats is made on a wall of the guide (42) facing the sliding block (41). [4] Centering unit (10) according to claim 3, wherein each longitudinal half-seat (47a, 47b) has a V-shaped or substantially triangular cross-section which is open on one side. [5] Centering unit (10) according to one of the preceding claims, wherein at least two connecting elements (43) project transversely from the sliding block (41) towards the interior of the housing body (11), designed to engage in a group of corresponding housing seats (44) provided on the sleeve of the centering rod (13). [6] Centering unit (10) according to claim 5, wherein at least two groups of housing seats (44) for receiving the connecting elements (43) are provided on the sleeve of the centering rod (13), wherein each group of housing seats (44) comprises a plurality of seats aligned along a direction parallel to the actuating axis (A), wherein each group of housing seats (44) is provided on the sleeve of the centering rod (13) in a different angular position. [7] Centering unit (10) according to one of claims 1 to 4, wherein the sliding block (41) is formed integrally with the centering rod (13). [8] Centering unit (10) according to one of the preceding claims, comprising an actuator (20) which is provided with an actuator body (23) which is connected to the housing body (11) and is configured to act on a control rod (14) which in turn is fixed to the centering rod (13), wherein the actuator is configured to move the control rod (14) linearly along a control axis between two end positions, a first position of maximum insertion into the actuator body (23) and a second position of minimum insertion into the actuator body (23). [9] Centering unit (10) according to claim 8, wherein the actuator body (23) is detachably connected to the housing body (11) at its bottom wall (11c). [10] Centering unit (10) according to claim 8 or 9, wherein a head wall (25b) of the actuator body (23), which acts as a connection interface with the housing body (11), and a bottom wall (11c) of the housing body (11), which acts as a connection interface with the actuator body (23), are shaped complementarily to implement a relative positioning guide between the actuator body (23) and the housing body (11), such that the drive axis (A) substantially coincides with the actuator control axis (20). [11] Centering unit (10) according to one of claims 8 to 10, wherein the actuator body (23) comprises a guide and centering projection (25a) which extends at least partially to the outside of the actuator body (23) from the head wall (25b) of the actuator body (23), which acts as a connection interface with the housing body (11). [12] Centering unit (10) according to claim 11, wherein the housing body (11) comprises a guide opening (37) which is produced on the bottom wall (11c) of the housing body (11) which acts as a connection interface with the actuator body (23), wherein the guide opening is designed to receive and cooperate with the guide and centering projection (25a) to implement the relative positioning guide. [13] Centering unit (10) according to claim 12, wherein the guide opening (37) has at least one section part which is complementary to a section of the guide and centering projection (25a) transversely to the actuating axis (A). [14] Centering unit (10) according to claim 13, wherein the at least one complementary section part of the guide opening (37) is coupled to the guide and centering projection (25a) by interference or substantially without play. [15] Centering unit (10) according to one of claims 10 to 14, wherein the bottom wall (11c) of the housing body (11) comprises a pair of screw seats (111d) arranged symmetrically according to a central symmetry with respect to an intersection of the actuating axis (A) on the bottom wall (11c). [16] Centering unit (10) according to one of claims 8 to 15, wherein the actuator body (23) comprises a pair of screws (27b) which pass through it parallel to the actuating axis (A) and are arranged in opposite angular positions with respect to the actuating axis (A). [17] Centering unit (10) according to any one of claims 8 to 16, wherein the actuator (20) is of an electrical type and comprises a cylindrical electromagnetic stator (21) and a cylindrical hollow magnetic rotor (24) within and coaxial to the electromagnetic stator (21), wherein the actuator control axis is a rotation axis of the hollow magnetic rotor. [18] Centering unit (10) according to claim 17, wherein a first termination (24a) of the magnetic rotor (24) projects from the actuator body (23) onto the guide and centering projection (25a). [19] Centering unit (10) according to claim 18, wherein the guide opening (37) is shaped to receive the first end (24a) projecting from the magnetic rotor (24) in a rotationally movable manner. [20] Centering unit (10) according to claim 18, wherein the magnetic rotor (24) is rotatably fixed about the control axis of the electric actuator on the actuator body (23) by means of an intermediate pair of bearings (31, 32), wherein a head wall (25) of the actuator body (23) defines a housing seat of a first bearing (31) of the pair of bearings (31, 32) which is directed inwards towards the actuator body (23), wherein the housing seat of the first bearing is preferably made on the guide and centering projection (25a).

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