Tool for inserting and removing temporary fasteners

Abstract

A tool for insertion and extraction of temporary fasteners that enables by a plurality of retractable elements, an automatic engagement of the tool on the head of the temporary fastener, without the need for any rotation of the tool with regard to the head, and by lockable grasping units, operated internally locking elements, a high retention and extraction force is achieved, favouring the elimination of the risk of the clamp detaching itself from the tool, enabling control of the entire insertion and extraction process of temporary fasteners. Rapid, effective automation of the use and procedure of the temporary fasteners can be achieved, improving economic profitability and the reliability of their use.

Claims

1. A tool for the insertion, installation and extraction of temporary fasteners of the type used in the aeronautical industry for the temporary joining of components during machining, drilling or shaving removal processing, associated with an external actuator module, characterized in that the nozzle (1) for the temporary fastener (2) has a cylindrical opening and comprises: one or more retractable elements (3), inserted into an axially disposed housing (12) and distributed peripherally on the inside of the nozzle (1), and partially embedded in the inside wall of the nozzle (1), one or more gripping units (4), also distributed peripherally on the inside of the nozzle, in a position closer to the outside and coinciding with a channel (14) of the temporary fastener (2) once inserted into the nozzle (1), associated with axially sliding locking elements (5) related to an internally actuated cylinder (6), a key (7) located in the central part of the tool, the head (8) thereof featuring a machined section suited to engage with that required for the movement of the inner part (11) of the temporary fastener (2), and featuring axial and rotational movement, one or more ejectors (9) disposed parallel to and adjacent to the key (7) endowed with axial movement.

2. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized by an extended position of the retractable elements (3) where each retractable element (3), independently of the others, is maintained in its extended position closest to the opening of the nozzle (1) by the thrust of a spring (13) inserted in the housing (12).

3. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized in that a retracted position of the retractable elements (3) where, independently of the others, the retractable element (3) which, due to its coincident position, is pushed by the head of the temporary fastener (2) when inserted into the nozzle (1), and moves axially towards the inside of the housing (12), pressing the spring (13).

4. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized in that the retractable elements (3) are distributed peripherally inside the nozzle (1) in such a way that, once the head of the temporary fastener (2) is inserted into the nozzle (1), and depending on its position, some or all of the retractable elements (3) remain in their extended position, laterally enveloping the head of the temporary fastener (2).

5. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized in that the retractable elements (3) are cylindrical.

6. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized in that there are 12 retractable elements (3).

7. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized by a free position of the gripping units (4) where the cylinder (6) and its locking elements (5) are slid into the tool, in such a way that the bevelled end (15) of the locking elements (5) remains in a position away from the gripping units (4), the latter remaining free to move within their housing (16).

8. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized by a locked position of the gripping units (4) where the cylinder (6) and its locking elements (5) are slid towards the nozzle (1) of the tool, in such a way that the bevelled end (15) of the locking elements (5) presses the gripping units (4), engaging them against the opening of their housing (16) towards the inside of the nozzle (1) and the channel of the fastener.

9. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized in that the gripping elements (4) feature a shape chosen from the group formed by cylindrical and spherical.

10. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized in that there are 3 gripping elements (4).

11. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized in that the key (7) is linked by means of a connector (17) to an external rotary actuator.

12. The tool for the insertion and extraction of temporary fasteners, as claimed in claim 1, characterized in that the ejector (9) is hollow and cylindrical and is coaxially disposed to and adjacent to the key (7).

Description

DESCRIPTION OF THE FIGURES

(1) In order to better understand the object of the present invention, a preferred practical embodiment of a tool for the insertion and extraction of temporary fasteners is portrayed in the annexed drawing. In the drawings:

(2) FIG. 1 portrays a sectional side view of the tool;

(3) FIG. 2 portrays an enlarged detail of the sectional side view of the tool, corresponding to the nozzle for the fastener, showing the locking elements and the grasping units;

(4) FIG. 3 portrays a section of the nozzle for the fastener, corresponding to the area of the locking elements;

(5) FIG. 4 portrays an enlarged detail in perspective of the tool nozzle, showing the locking elements and the grasping units;

(6) FIG. 5 portrays an example of a temporary fastener that can be used with this tool;

(7) FIG. 6 portrays a simplified detail of a side view of the front of the tool during the step of tool engagement with the temporary fastener;

(8) FIG. 7 portrays a simplified detail of a side view of the front of the tool during the step of engaging the temporary fastener via the hexagon forming the head of the clamp;

(9) FIG. 8 portrays a simplified detail of a side view of the front of the tool during the step of inserting the actuating key into the temporary fastener;

(10) FIG. 9 portrays a simplified detail of a side view of the front of the tool during the step of locking the temporary fastener;

(11) FIG. 10 portrays a simplified detail of a side view of the front part of the tool during the step of releasing the pre-load of the temporary fastener by means of the actuating key;

(12) FIG. 11 portrays a simplified detail of a side view of the front of the tool during the step of removing the temporary fastener from the component being worked on, when commencing extraction;

(13) FIG. 12 portrays a simplified detail of a side view of the front of the tool during the step of removing the temporary fastener from the component being worked on, during extraction;

(14) FIG. 13 portrays a simplified detail of a side view of the front of the tool during the step of releasing the temporary fastener lock;

(15) FIG. 14 portrays a simplified detail of a side view of the front of the tool during the step of ejecting the temporary fastener into its store;

(16) FIGS. 15a to 15g portray several examples of engagement with a type of temporary fastener which is centred regarding the tool nozzle, with different relative angles of rotation, showing shaded the retractable elements that remain in the extended position, and which may be locked; and

(17) FIGS. 16a to 16g portray several examples of engagement with a type of temporary fastener that is off-centre regarding the tool nozzle, with different relative angles of rotation, showing shaded the retractable elements that remain in the extended position.

PREFERRED EMBODIMENT OF THE INVENTION

(18) The tool for inserting and extracting temporary clamps which is the object of the present invention, is basically characterized, as may be seen in the attached drawing, in that the nozzle (1) for the temporary fastener (2) has a cylindrical opening and comprises: one or more retractable elements (3), inserted into an axially disposed housing (12) and distributed peripherally on the inside of the nozzle (1), and partially embedded in the inside wall of the nozzle (1), one or more grasping units (4), also distributed peripherally on the inside of the nozzle, in a position closer to the outside and coinciding with the channel (14) of the corresponding temporary fastener (2) once inserted into the nozzle (1), associated with a number of axially sliding locking elements (5); all of these related to an internally sliding actuating cylinder (6), held in the locked position by an internal spring (10), which can optionally be replaced by a thrust cylinder, a key (7) located in the central part of the tool, the head (8) thereof featuring a machined section suited to engage with that required for the actuation of the inner part (11) of the temporary fastener (2), and featuring axial and rotational movement, one or more ejectors (9) disposed parallel to and adjacent to the key (7) endowed with axial movement.

(19) The retractable elements (3) may adopt an extended position in which each retractable element (3), independently of the others, is maintained in its position closest to the nozzle opening (1) by the thrust of a spring (13) inserted in the housing (12), or in a retracted position in which, independently of the others, the retractable element (3) which due to its coincident position is pushed by the head of the temporary fastener (2) when inserted into the nozzle (1), moves axially into the housing (12), pressing against the spring (13).

(20) These retractable elements (3) are distributed peripherally inside the nozzle (1) in such a way that, once the head of the temporary fastener (2) has been inserted into the nozzle (1), and depending on its position, some or all of the retractable elements (3) remain in their extended position, laterally enveloping the head of the temporary fastener (2). The shape of the retractable elements (3) shall preferably be cylindrical, and the preferred number of retractable elements (3) is 12, which, according to experimental tests, has proved to be the most effective for temporary components (1) with hexagonal heads, although the number may be configurable depending on the shape of the head of the temporary fastener.

(21) The grasping units (4) can also adopt a free position in which the cylinder (6) and its locking elements (5) slide into the tool, compressing the spring (10) in such a way that the bevelled extremity (15) of the locking elements (5) remains in a position away from the grasping units (4), these being free to move within their housings (16), or a locked position where the cylinder (6) and its locking elements (5) are slid towards the tool nozzle (1) due to the thrust of the spring (10) in such a way that the bevelled end (15) of the locking thrusters (5) lies on the grasping units (4), locking them against the opening of their housing (16) into the nozzle (1).

(22) These grasping units (4) have a shape, depending on the channel of the temporary fastener, chosen from the group formed by cylindrical and spherical, being preferably cylindrical, and there being preferably 3 grasping units (4).

(23) The key (7) is coupled by means of a connector (17) to a rotary actuator selected among electric, pneumatic, hydraulic or mechanical systems.

(24) The ejector (9) is preferably of the hollow cylindrical type disposed coaxially to the key (7) and next to the same.

(25) This tool for the insertion and extraction of temporary fasteners also has a characteristic operating procedure, which may be divided into two parts, one for the extraction of temporary parts (1) inserted into a component (18), and the opposite process of insertion of temporary parts (1) from the store to the component (18), sharing many common steps.

(26) The tool is equipped with the appropriate position, status and force sensors necessary to control the movement and status of the different internal elements and to facilitate the programming of its automated use.

(27) To extract a temporary fastener (2) fixed in a component (18):

(28) first of all, a step of engaging the tool nozzle with the temporary fastener (2) is performed, with the automatic gripping of the temporary fastener (2)

(29) secondly, a step consisting of locking the temporary fastener (2),

(30) thirdly, a step where the key (7) is inserted into the temporary fastener,

(31) the fourth step is to release the pre-load of the temporary fastener (2),

(32) in fifth place a step of extracting the temporary fastener (2) from the component (18) being worked on,

(33) the sixth step is to release the temporary fastener (2), and

(34) the seventh step is to eject the temporary fastener (2) into its store.

(35) To carry out the insertion of a temporary fastener (2) into a component (18), one should proceed as follows:

(36) first of all, the step of engaging the tool nozzle in the temporary fastener (2), located in the store or received automatically by the feed system, with automatic grasping of the head of the temporary fastener

(37) secondly, a step consisting of locking the temporary fastener (2),

(38) thirdly, a step of inserting the temporary fastener (2) into the component (18) through a hole drilled previously,

(39) fourthly, a step of inserting the key (7) into the temporary fastener,

(40) in fifth place a step of pre-loading the temporary fastener (2),

(41) the sixth step is to release the temporary fastener (2), and

(42) in seventh place, the step of extracting the tool, leaving the temporary fastener (2) gripped in the component.

(43) The step of engaging the tool in the temporary fastener (2), comprises the forward movement of the tool by means of the external actuation module, inserting it in a given position, the retractable elements (3) adopting an extended or retracted position depending on the relative positions of the head of the temporary fastener (2) and the nozzle (1) of the tool.

(44) The step of locking the temporary fastener (2) by means of the radial channel. It comprises the forward movement of the tool while the gripping elements (4), being free-moving, are retracted by the thrust of the head of the fastener (2).

(45) The step of inserting the key (7) into the temporary fastener is carried out by turning the key at a reduced speed and with controlled torque, detecting the moment of connection.

(46) The step of locking the temporary clamp (2) is carried out by releasing the pressure on the actuating cylinder (6), thereby activating the spring (10) that pushes the locking elements (5) forward, locking the gripping items (4), which engage in the channel (14) of the temporary fastener (2).

(47) The step of releasing the pre-load of the temporary fastener (2) is carried out by turning the motor of the external actuator module, causing the key (7) to rotate inside the temporary fastener (2) at a programmed speed and with a certain release torque.

(48) The step of extraction of the temporary clamp (2) from the component (18) being worked on is carried out by means of the withdrawal of the tool and the temporary fastener (2) solidary with it, from the external actuator module.

(49) The step of releasing the temporary fastener (2) is carried out by means of the entry of air into the actuating cylinder (6), moving it rearward together with the locking elements (5), unlocking the grasping units (4), which once free can now leave the channel (14) of the temporary fastener (2).

(50) The step of ejecting the temporary fastener (2) into its store involves maintaining the actuating cylinder (6) actuated in order to hold the locking elements (5) back, and actuating the ejector or ejectors (9) to push the fastener out and deposit it in its store.

(51) The step of insertion of the temporary clamp (2) into the component (18) through a previously drilled hole is carried out by means of the forward movement performed by the tool and the temporary fastener (2) solidary therewith, driven by the external actuator module.

(52) The step of pre-loading the temporary fastener (2) is carried out by turning the motor of the external actuator module, causing the key (7) to rotate inside the temporary fastener (2) at a programmed speed and with a certain tightening torque.

(53) The step of extracting the tool leaving the temporary fastener (2) grasped by the component is carried out by means of the rearward movement performed by the tool, drawn by the external actuator module.

(54) During the step of inserting the tool into the temporary clamp (2), the retractable elements (3) adopt an extended or retracted position depending on the relative position of the temporary fastener head (2) with the nozzle (1) of the tool. This is shown experimentally in the following simulations performed:

(55) The specific use of this tool is for the insertion and extraction of temporary fasteners (2) with different head shapes, in particular a hexagonal shape, although it is easily adaptable to other types of head, such as octagons, 36-spiked splines, etc.

(56) In FIG. 15, several examples with a temporary fastener with a hexagonal head (2) may be seen, centred with regard to the nozzle (1) of the tool, with different relative rotation angles.

(57) Thus, in FIG. 15a a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 0°. In this case, 6 retractable elements (3) would be in the retracted position, and 6 retractable elements (3) would be in the extended position.

(58) In FIG. 15b a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 5°. In this case 6 retractable elements (3) would be in the retracted position and 6 retractable elements (3) would be in the extended position.

(59) In FIG. 15c a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 10°. In this case 6 retractable elements (3) would be in the retracted position and 6 retractable elements (3) would be in the extended position.

(60) In FIG. 15d a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 12°. In this case 12 retractable elements (3) would be in the extended position.

(61) In FIG. 15e a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 14°. In this case 12 retractable elements (3) would be in the extended position.

(62) In FIG. 15f a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 5°. In this case 12 retractable elements (3) would be in the extended position.

(63) In FIG. 15g a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 20°. In this case 12 retractable elements (3) would be in the extended position.

(64) We verify that in all these cases the rotation of the temporary fastener (2) inside the tool is halted.

(65) In FIG. 16 several examples with the temporary fastener (2) 0.3 mm. off-centre with regard to the nozzle (1) of the tool may be seen, with different relative rotation angles.

(66) In FIG. 16a a temporary clamp (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 0°, and 0.3 mm off-centre. In this case 6 retractable elements (3) would be in the retracted position and 6 retractable elements (3) would be in the extended position.

(67) In FIG. 16b a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 5°, and 0.3 mm off-centre. In this case 4 retractable elements (3) would be in the retracted position and 8 retractable elements (3) would be in the extended position.

(68) In FIG. 16c a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 10°, and 0.3 mm off-centre. In this case 4 retractable elements (3) would be in the retracted position and 8 retractable elements (3) would be in the extended position, and at this moment, two retractable elements (3) tend to centre the fastener.

(69) In FIG. 16d a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 12°, and 0.3 mm off-centre. In this case 4 retractable elements (3) would be in the retracted position and 8 retractable elements (3) would be in the extended position.

(70) In FIG. 16e a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 14°, and 0.3 mm off-centre. In this case 4 retractable elements (3) would be in the retracted position and 8 retractable elements (3) would be in the extended position.

(71) In FIG. 16f a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 15°, and 0.3 mm off-centre. In this case 4 retractable elements (3) would be in the retracted position and 8 retractable elements (3) would be in the extended position.

(72) In FIG. 16g a temporary fastener (2) centred with regard to the nozzle (1) may be seen, with an angle from the vertical of 20°, and 0.3 mm off-centre. In this case 4 retractable elements (3) would be in the retracted position and 8 retractable elements (3) would be in the extended position.

(73) We verify that in all these cases the rotation of the temporary fastener (2) is locked within the tool.

(74) It will be easy for any person skilled in the art to understand that the characteristics of different embodiments can be combined with characteristics of other possible embodiments whenever such a combination is technically possible.

(75) All the information referring to examples or modes of embodiment, form part of the description of the invention.