FR3088841A1 - Collaborative gripper - Google Patents

Abstract

Gripper (1) with adjustable spacing comprising: - a frame (2); - a first arm (5) slidably mounted on the frame (2) and provided with a first clamping jaw (9); - a second clamping jaw (10); - a first clamping bar (30) integral with the first arm (5); - an actuation unit (31) for applying a clamping force between the first jaw (9) and the second jaw (10); - first controllable means of coupling (40) of the actuation unit (31) and of the first clamping bar (30) which can selectively adopt a first state in which the relative movements of the actuation unit (31 ) and the first clamping bar (30) are free and a second state in which the actuating unit (31) applies a force to the first clamping bar (30).

Description

Description

Title of the invention: Collaborative gripper

Technical field [0001] The invention relates to the field of handling and more particularly the field of grippers.

BACKGROUND OF THE INVENTION A handling device generally comprises a load balancer, the end of which is equipped with a load gripper for gripping a load to be handled. A load gripper is conventionally composed of two arms mounted in rotation or in translation on a frame and between which extends a clamping cylinder. The end of each of the arms is provided with a clamping jaw. When a user wishes to clamp a load, he actuates the hydraulic cylinder which brings the arms together and thus allows the jaws to apply a clamping force to a load placed between the two jaws. When handling loads of various widths, it is necessary to adjust the distance between the jaws each time the load width is changed. This adjustment is made using the clamping cylinder. Generally, the cylinder rod exit speed is low to avoid damaging the loads to be handled during the application of the clamping force. Thus, the time required to adapt the gripper to the new width of a load is long and impacts the handling rates, which limits the diffusion of load grippers for applications in which loads of various widths are to be treated.

OBJECT OF THE INVENTION The object of the invention is to improve the load handling rates of various widths using a load gripper.

Disclosure of the invention To this end, there is provided, according to the invention an adjustable spacing gripper comprising a frame, a first arm slidably mounted on the frame and provided with a first clamping jaw, a second jaw clamp linked to the frame and a first clamping bar secured to the first arm. The gripper also includes a first handle connected to the first arm, an actuation unit for applying a clamping force between the first jaw and the second jaw, first controllable means for coupling the actuation unit and the first bar. tightening which can selectively adopt a first state in which the relative movements of the actuating unit and the first clamping bar are free and a second state in which the actuating unit applies the clamping force to the first bar Clamping.

Such a gripper allows, when the controllable coupling means are in their first free state, to adjust the spacing of the jaws manually and, once the controllable coupling means in their second state, the application by the unit actuation of a clamping force. The operation of such a gripper is intuitive for the arm spacing adjustment phase and this phase takes place particularly quickly. The clamping force is applied by the actuation unit and not by the operator, which reduces the operator's fatigue.

The gripper is light and economical to produce when the actuation unit comprises a first actuator and the change of state of the first controllable coupling means is controlled by the first actuator.

The implementation is particularly economical and reliable when the actuation unit includes a screw.

The gripper is particularly reliable when the first controllable coupling means comprise a first bracing shoe.

The gripper is compact and light when the screw collaborates with a nut connected to the first bracing shoe.

A reliable and economical design is obtained when the first controllable coupling means are connected to a trigger secured to the first handle.

The ergonomics of the gripper is improved when the position of the first handle is adjustable in a direction substantially orthogonal to that of the clamping force.

The handling rate is further improved by a reduction in the range of movement of the first arm when the gripper includes a first adjustable stop limiting the movement of the first arm.

The fatigue of a user is reduced, and the handling rate thus improved, when the inertia of the first arm does not include the inertia of the actuator.

The setting of the spacing of the gripper arms is faster when the second clamping jaw is integral with a second clamping arm connected to a second handle, the second clamping arm being slidably mounted on the frame, the second clamping arm being integral with a second clamping bar, the gripper also comprising second controllable means for coupling the actuating unit and the second clamping bar to selectively adopt a third state in which the relative movements of the actuation unit and the second clamping bar are free and a second state in which the actuating unit applies a force to the second clamping bar.

The gripper is light and economical to produce when the change of state of the second controllable coupling means is controlled by the first actuator.

The gripper is particularly reliable when the second mandable coupling means corn3 comprise a second bracing shoe.

The realization of the gripper is particularly economical when the actuation unit comprises a first motor linked to the second hoof pad to move with the second hitch pad.

The ergonomics of the gripper is improved when the position of the second handle is adjustable in a direction substantially orthogonal to that of the clamping force.

The speed of adjusting the spacing of the arms is improved when the gripper comprises a device for associating the movements of the first arm and the second arm arranged to cause a displacement of one of the first and second arms when the other of the first and second arms is moved. Such a device makes it possible to ensure that the package seized is well centered relative to the frame. Advantageously, the association device comprises a first pulley rotatably mounted on the frame and a second pulley rotatably mounted on the frame, a first cable cooperating with the first pulley has a first end secured to the first arm and a second end secured to the second arm, a second cable cooperating with the second pulley has a third end secured to the first arm and a fourth end secured to the second arm.

The handling of parts is facilitated when the gripper comprises at least one motor for rotating the first jaw and / or the second jaw. Preferably, a coupling device rotates the first jaw and the second jaw.

The handling rate is further improved when the actuation unit is controlled by a force sensor located in the first handle and / or by a force sensor located in the second handle.

The fatigue of a user is reduced, and the handling rate thus improved, the inertia of the first arm and / or of the second arm does not include the inertia of the first actuator.

The invention also relates to a handling device comprising a gripper as described above, the handling device may include a passive or active load balancer.

Other characteristics and advantages of the invention will emerge in the light of the following description of particular non-limiting embodiments of the invention. Brief description of the drawings Reference will be made to the appended figures, among which:

[Fig. 1] Figure 1 is a schematic perspective view of a first embodiment of the invention;

[Fig.2] Figure 2 is a schematic detail view in plan of Figure 1;

[Fig-3] Figure 3 is a partial schematic plan view of Figure 1;

[Fig.4] Figure 4 is a partial schematic detail view of a first free state of the gripper of Figure 1;

[Fig.5] Figure 5 is a partial schematic detail view of a second locked state of the gripper of Figure 1;

[Fig.6] Figure 6 is a schematic detail view in section of a first arboutement shoe of the gripper of Figure 1;

[Fig.7] Figure 7 is a schematic view of the gripper of Figure 1 in an initial state;

[Fig.8] Figure 8 is a partial schematic representation of a state of the gripper of Figure 1 during load handling;

[Fig.9] Figure 9 is a partial schematic representation of a state of the gripper of Figure 1 during load handling;

[Fig.10] Figure 10 is a partial schematic representation of a state of the gripper of Figure 1 during load handling;

[Fig.l 1] Figure 11 is a schematic perspective view of a second embodiment of the invention;

[Fig. 12] Figure 12 is a schematic detailed plan view of Figure 11;

[Fig. 13] Figure 13 is a partial schematic plan view of Figure 11;

[Fig.14] Figure 14 is a partial schematic detail view of a first free state of the gripper of Figure 11;

[Fig. 15] Figure 15 is a partial schematic view of detail of a second locked state of the gripper of Figure 11;

[Fig. 16] Figure 16 is a schematic detail view in section of a first arboutement shoe of the gripper of Figure 11;

[Fig. 17] Figure 17 is a partial schematic plan view of Figure 11;

[Fig. 18] Figure 18 is a schematic perspective view of a third embodiment of the invention;

[Fig. 19] Figure 19 is a schematic perspective view of a fourth embodiment of the invention;

[Fig.20] Figure 20 is a schematic perspective view of a fifth embodiment of the invention;

[Fig.21a] Figure 21a is a partial schematic perspective view of the gripper of Figure 20 in a first configuration of the arms of the gripper;

[Fig.21b] Figure 21b is a partial schematic perspective view of the gripper of Figure 20 in a first configuration of the gripper arms;

[Fig.22a] Figure 22a is a partial schematic perspective view of the gripper of Figure 20 in a second configuration of the gripper arms;

[Fig.22b] Figure 22b is a partial schematic perspective view of the gripper of Figure 20 in a second configuration of the gripper arms.

Description of the embodiments With reference to FIGS. 1 to 7, the collaborative gripper with adjustable spacing according to the invention, and generally designated 1, is mounted at the end of an articulated arm 80 (partially shown) with six motorized axes intended to achieve active balancing of the gripper 1.

The gripper 1 comprises a frame 2, here a steel rectangle tube under the base 3 of which is welded a T-shaped sliding rail 4. The gripper 1 also comprises a first arm 5 on the upper end 6 of which two sliding pads 7.1 and 7.2 are screwed in PTFE. The pads 7.1 and 7.2 are slidably engaged on the rail 4 to allow the first arm 5 to slide relative to the frame 2 in a first direction Ox.

The lower end 8 of the first arm 5 is provided with a first clamping jaw 9, here a circular non-slip rubber plate. A second clamping jaw 10 identical to the first jaw 9 is fixed to the lower end 11 of a second arm 12 whose upper end 13 is welded to the frame 2. The first arm 5 comprises a first cylindrical guide 14 s' extending along the first arm 5 and on which slides a first slide 15 which carries a first handle 16. The first slide 15 can be locked in position on the first guide 14 by means of a first clamping eccentric 17. In a homologous manner, the second arm 12 comprises a second cylindrical guide 18 extending along the second arm 12 and on which slides a second slide 19 which carries a second handle 20. The second slide 19 can be locked in position on the second guide 18 by means of a second clamping eccentric 21.

As shown in Figure 1, a first clamping bar 30 secured to the upper end 6 of the first arm 5 extends in a direction parallel to the first direction Ox. The first clamping bar 30 has here a rectangular section of width 130 and height L30.

The gripper 1 also includes an actuation unit 31 which comprises a first electric motor 32 screwed onto the frame 2. A pinion 33 cooperates with a toothed belt 34 which itself cooperates with a toothed wheel 35 integral in rotation with the first end 36 of a screw 37 with metric thread. The screw 37 extends in a direction substantially parallel to the first direction Ox. A first nut 38 is engaged on the screw 37 near the second end 39 of the screw 37. As visible in FIGS. 3 and 4, the first nut 38 is pivotally mounted on a first bracing pad 40 engaged on the first clamping bar 30.

As shown in Figure 4 to 6, the first bracing pad 40 comprises a parallelepiped body 41 of longitudinal axis 041, which defines a first passage 42 for the first clamping bar 30. The first passage 42 is delimited by the distal end 43.1 of an upper tooth 43 and the distal end 44.1 of a lower tooth 44 which are situated on either side of the longitudinal axis 041. The distance D42 considered along the longitudinal axis 041 and which separates the distal part 43.1 of the upper tooth 43 from the distal part 44.1 of the lower tooth 44 is substantially less than the height L30 of the first clamping bar 30. The distance d42 considered in the first direction Ox and which separates the distal part 43.1 of the upper tooth 43 of the distal part 44.1 of the lower tooth 44 is non-zero. The first bracing shoe 40 also comprises two second lateral rollers 45.1 and 45.2 mounted for rotation about a second axis 045 orthogonal to the first axis Ox and to the longitudinal axis 041. The second lateral rollers 45.1 and 45.2 cooperate respectively with slots 46.1 and 46.2 oblong of an anti-rotation tube 47 connected to the frame 2 by means of a pin 48.1 secured to the frame 2 and mounted to slide in a vertical direction (as shown in Figure 4 ) in an oblong slot 48.2 of the anti-rotation tube 47. A first sliding pad 47.1 secured to the interior of the anti-rotation tube 47 and placed near the first end 49.1 of the anti-rotation tube 47 allows easy sliding of the first clamping bar 30 on the anti-rotation tube 47.

The mass of the motor 32 being taken up by the frame 2, the inertia of the first arm 5 therefore does not include the inertia of the motor 32.

The first arch pad 40 can selectively therefore adopt two states relative to the first clamping bar 30: a first free state in which the longitudinal axis 041 of the first pad 40 extends at an angle a41 strictly greater than ninety degrees with the first direction Ox, here an angle of one hundred degrees (Figure 4), and a second blocked state in which the longitudinal axis 041 of the first arch pad 40 extends forming an angle a41 substantially equal to ninety degrees with the first direction Ox (FIG. 5). The passage of the first arbout pad 40 from its first free state to its second locked state is effected by rotation of the first arbout pad 40 around the second axis 045 by controlling a rotation of the first motor 32 in a first direction of rotation . The reverse passage of the first hitch pad 40 from its second locked state to its first free state is effected by controlling a rotation of the first motor 32 in a second direction of rotation opposite to the first.

When the first hitch pad 40 is in its first free state (Figure 4), the relative movements of the actuating unit 31 and the first clamping bar 30 are free. When the first arcuate pad 40 is in its second locked state (FIG. 5), there is an arcboutement between the first clamping bar 30 and the assembly consisting of the upper tooth 43 and the lower tooth 44. In this second state , the relative movements of the actuating unit 31 and the first clamping bar 30 are blocked and an additional rotation of the screw 37 under the effect of the first motor 32 causes the application of a force of the screw 37 on the first nut 38. This force is then transmitted from the first nut 38 to the first clamping bar 30 via the first bracing pad 40 and makes it possible to apply a clamping force in a direction substantially parallel to the axis Ox . This clamping force is transmitted by the first arm 5 to the first jaw 9.

The first motor 32 is supplied via a power cable not shown by an external wired network and is connected to a control unit 81. A first switch 50 Normally Open secured to the first handle 16 is also connected to the control unit 81 for controlling the power supply to the first motor 32. The first motor 32 also includes a torque sensor 82 connected to the control unit 81 Finally, a first bracket 51 is fixed to the frame 2 to 1 using two knurled screws 55.1 and 55.2 extending in a branch 53 made in the first branch 54 of the first bracket 51. The second branch 55 extends parallel to the first arm 5 in the plane of the latter.

Prior to the use of the gripper 1, an operator positioned the second branch 55 so that when the first arm 5 is in abutment on the second branch 55 of the first bracket 51, the distance separating the first jaw 9 and the second jaw 10 corresponds substantially to the width of the widest load to be grasped. Once the second branch 55 has been positioned, the operator blocks the position using the two knurled screws 55.1 and 55.2. The first bracing shoe 40 is in its first free state in which the relative movements of the actuating unit 31 and the first clamping bar 30 are free.

In operation, the operator grasps the first handle 16 and the second handle 20. He spreads them in order to cause a relative distance of the first arm 5 and the second arm 12 until the first arm 5 comes in abutment on the second branch 55 of the first bracket 51 (Figure 7).

When he wishes to enter a load - here a parallelepipedic package 83 - the operator places the package 83 between the first jaw 9 and the second jaw 10 (Figure 8) and exerts a force on the first handle 16 and the second handle 20 aimed at bringing the first arm 5 and the second arm 12 closer. During this maneuver, the first clamping bar 30 slides freely relative to the frame 2 in the first passage 42 of the first bracing pad 40. When the first jaw 9 and second jaw 10 are each in contact with a flank of the package 83 (FIG. 9), the operator actuates the first switch 50. The control unit 81 then detects a gripping instruction and controls a rotation of the first motor 32 in the first direction of rotation. The first bracing pad 40 then passes into its second blocked state shown in FIG. 5. Whether or not the operator maintains the pressure, the first switch 50, the control unit 81 maintains a torque control of the first motor 32 which causes the application of a tightening force of the screw 37 on the first nut 38. The tightening force is then transmitted from the first nut 38 to the first tightening bar 30 via the first bracing shoe. 40. The first clamping bar 30 which is integral with the first arm 5 transmits this force to the first jaw 9. When the torque C ₃₂ reaches a predetermined threshold value Cs ₃₂ (which can be fixed as a function of a load range of packages and / or the packaging thereof), the control unit 81 orders the first motor 32 to stop. The package 83 is therefore clamped between the first jaw 9 and the second jaw 10 (FIG. 10) and the operator can move the parcel 83 by acting, using the first handle 16 and the second handle 20, on the gripper 1 and incidentally the articulated arm 80 which provides efforts to compensate for the weight of the gripper 1 and of the package 83 (active balancing).

When he wishes to place the package 83, the operator brings the package 83 vertically to its destination and presses again on the first switch 50. The control unit 81 then controls a rotation of the first motor 32 in the second direction until the torque sensor 82 indicates zero torque for one second. Once the package 83 has been released, the operator acts again on the first handle 16 and the second handle 20 to adapt the spacing of the first jaw 9 relative to the second jaw 10 to the size of the next package to be handled.

A device is thus obtained which makes it possible to quickly adjust the spacing of a load gripper to the size of a package to be handled without compromising the quality, speed and conformity of the tightening applied to the package to be handled.

Elements identical or analogous to those previously described will bear a reference numeral identical to these in the following description of the second, third and fourth embodiments of the invention.

According to a second embodiment shown in Figure 11, the upper end 13 of the second arm 12 comprises two pads 7.3 and 7.4 for sliding in PTEE. The pads 7.3 and 7.4 are slidably engaged on the rail 4 to allow the second arm 12 to slide relative to the frame 2 in the first direction Ox.

As shown in Figures 11 and 12, a second clamping bar 60 secured to the upper end 13 of the second arm 12 extends coaxially to the first clamping bar 30 in a direction parallel to the first direction Ox and is also engaged in the second end 49.2 of the anti-rotation tube 47. A second sliding pad 47.2 secured to the interior of the anti-rotation tube 47 and placed near the second end 49.2 of the anti-rotation tube 47 opposite the first end 49.1 allows easy sliding of the first clamping bar 30 on the anti-rotation tube 47. The second clamping bar 60 here has a rectangular section of width 160 and height L60.

As shown in Figures 12 to 16 and unlike the first embodiment, the first motor 32 is, here, not directly connected to the frame 2 but is screwed onto a flange 62 comprising a bearing 63 for guiding in rotation of the screw 37. A ball stop 68 is engaged on the screw 37 near the first end 36 of the screw 37 so that the flange 62 is located between the toothed wheel 35 and the ball stop 68. The stop ball 68 is mounted on the screw 37 so as to allow the rotation of the screw 37 relative to the flange 62. The flange 62 comprises a shaft 64 extending substantially orthogonally to the axis Ox and which is mounted at pivoting in a body 71 of a second bracing shoe 70 engaged on the second clamping bar 60.. A compression spring 61 extends, here, parallel to the screw 37 between the first padding pad 40 and the second padding pad 70 to exert a force aimed at moving the first padding pad 40 away from the second pad d arch 70.

As shown in Figure 14 to 16, the body 71 of the second bracing shoe 70 is parallelepipedal with a longitudinal axis 071, which defines a second passage 72 for the second clamping bar 60. The second passage 72 is delimited by the distal end 73.1 of an upper tooth 73 and the distal end 74.1 of a lower tooth 74 which are situated on either side of the longitudinal axis 071. The distance D72 considered along the longitudinal axis 071 and which separates the distal part 73.1 of the upper tooth 73 from the distal part 74.1 of the lower tooth 74 is substantially less than the height L60 of the second clamping bar 60. The distance d72 considered along the first axis Ox and which separates the distal part 73.1 of the upper tooth 73 of the distal part 74.1 of the lower tooth 74 is not zero. The second bracing shoe 70 also comprises two second lateral rollers 75.1 and 75.2 mounted for rotation about a third axis 075 orthogonal to the first axis Ox and to the longitudinal axis 071. The second lateral rollers 75.1 and 75.2 cooperate respectively with oblong lights 76.1 and 76.2 of the anti-rotation tube 47.

Thus, the weight of the motor 32 is transmitted by the second arboutement shoe 70 to the anti-rotation tube 47 using the rollers 75.1 and 75.2. The anti-rotation tube 47 then takes up the weight of the motor 32 which it transmits to the first clamping bar 30 and to the second clamping bar 60 via the first pad 47.1 and the second pad 47.2. Thus, the displacements of the engine 32, the first arm 5 and the second arm 12 are thus decoupled and the inertia of the motor 32 is not added to that of the first arm 5 or the second arm 12. The inertia of the first arm 5 and the second arm 12 therefore does not include the inertia of the motor 32.

The second arch pad 70 can selectively therefore adopt two states relative to the second clamping bar 60: a first free state in which the longitudinal axis 071 of the second pad 70 extends at an angle α71 strictly greater than ninety degrees with the first direction Ox, here an angle of one hundred degrees (Figure 14), and a second blocked state in which the longitudinal axis 071 of the second arch pad 70 extends forming an angle a71 substantially equal to ninety degrees with the first direction Ox (FIG. 15).

The transition from the second arbout pad 70 from its first free state to its second locked state is effected by rotation of the second arbout pad 70 around the third axis 075 by controlling a rotation of the first motor 32 in a first sense of rotation. During the rotation of the screw 37 in a first direction caused by the rotation of the first motor 32 in the first direction, the relative movement of the screw 37 and the nut 38 causes a rotation - which may or may not be simultaneous depending on the inertias in play - the first arch pad 40 around its second axis 045 and the second butt pad 70 around its third axis 075. The tilting of the first pad 40 and the second pad 70 is particularly favored by the spring 61, the support points on the first arcboutement pad 40 and the second arcboutement pad 70 provides a first and a second center of rotation around which the tilting takes place. The first arbout pad 40 and the second arbout pad 70 then go from their first free state to their second locked state.

The reverse passage of the second hoop shoe 70 from its second locked state to its first free state is effected by controlling a rotation of the first motor 32 in a second direction of rotation opposite to the first. This rotation of the first motor 32 in the second direction also causes the passage of the first hoop pad 40 from its second blocked state to its first free state.

When the second hitch pad 70 is in its first free state, the relative movements of the actuating unit 31 and the second clamping bar 60 are free. When the second arch pad 70 is in its second locked state, there is an arch between the second clamping bar 60 and the assembly consisting of the upper tooth 73 and the upper tooth 74. In this second state, the relative movements the actuating unit 31, the first clamping bar 30 and the second clamping bar 60 are blocked and an additional rotation of the screw 37 under the effect of the first motor 32 causes the application of a force from the screw 37 on the ball stop 68. This force is then transmitted from the ball stop 68 to the second clamping bar 60 via the flange 62 and the second bracing shoe 70. This force makes it possible to apply a force clamping in a direction substantially parallel to the axis Ox to the second clamping bar 60.

As shown in Figure 17, the gripper 1 also includes an association device 90 of the movements of the first arm 5 and the second arm 12. The association device 90 comprises a first pulley 91 rotatably mounted at a first end 2.1 of the frame 2. The association device 90 also comprises a second pulley 92 rotatably mounted at a second end 2.2 of the frame 2 opposite the first end 2.1. A first cable 93 cooperates with the first pulley 91 and has a first end 93.1 secured to the first arm 5 and a second end 93.2 secured to the second arm 12. A second cable 94 cooperates with the second pulley 92 and has a third end 94.1 secured to the first arm 5 and a fourth end 94.2 secured to the second arm 12.

Thus, when the operator causes a displacement of the first arm 5 towards the center of the gripper 1 (here a translation to the right according to the representation of FIG. 17), the second arm 12 performs a homologous displacement and moves towards the center of the gripper 1 (here a translation to the left as shown in Figure 17). In the same way a movement of the arm 5 towards the first end 2.1 of the frame 2 (here a translation to the left according to the representation of FIG. 17), causes a movement of the second arm 12 the second end 2.2 of the frame 2 (here a translation to the right as shown in Figure 17).

The use of the gripper 1 according to the second embodiment of the invention is identical to that described for the gripper according to the first embodiment. The association of the first and second arms via the association device 90 makes it possible to guarantee that the package seized is indeed at the axis of the gripper and thus plumb with a point of attachment of the gripper 1 to the articulated arm 80. Switching from one package format to another is also faster.

The tightening of the package is also faster thanks to the joint tightening movement of the first jaw 9 and the second jaw 10.

According to a third embodiment shown in Figure 18, the first jaw 9 is rotatably mounted on the first arm 5 along an axis substantially parallel to the axis Ox and the second jaw 10 is rotatably mounted on the second arm 12 along an axis substantially parallel to the axis Ox. The rotation of the first jaw 9 is controlled by a second motor 84 whose output shaft 84.1 is integral in rotation with the first jaw 9 and the rotation of the second jaw 10 is controlled by a third motor 85 whose output shaft 85.1 is integral in rotation with the second jaw 10. The second motor 84 and third motor 85 are connected to a second switch 56 integral with the second handle 20 and which is also connected to the control unit 81 for controlling the electrical supply of the second motor 84 and the third motor 85. Thus, the operator can cause the manipulated load to pivot about an axis substantially parallel to the axis Ox.

According to a fourth embodiment shown in FIG. 19, the first handle 16 comprises a first piezometric force sensor 16.1 and the second handle 20 comprises a second piezometric force sensor 20.1, both connected to the control 81. The first force sensor 16.1 is arranged to detect the direction of a force applied in a direction substantially parallel to the axis Ox.

The second force sensor 20.1 is arranged to detect the direction of a force applied in a direction substantially parallel to the axis Ox.

In operation, when the control unit 81 detects using the first force sensor 16.1 an application on the first handle 16 of a control force greater than a predetermined threshold - here a threshold greater than the resistance to sliding of the first arm 5 relative to the frame 2- in a first direction corresponding to a movement aimed at approaching the first arm 5 of the axis of the gripper 1 (here to the right according to FIG. 19), the control unit 81 controls a rotation of the first motor 32 in a first direction. In a homologous manner, when the control unit 81 detects using the first force sensor 16.1 an application to the first handle 16 of a control force greater than a predetermined threshold - here a threshold greater than the resistance to sliding of the first arm 5 relative to the frame 2- in a second direction corresponding to a movement aimed at moving the first arm 5 away from the axis of the gripper 1 (here to the left according to FIG. 19), the control unit 81 controls a rotation of the first motor 32 in a second direction opposite to the first.

The unit 81 acts in the same way for the second force sensor 20.1. Thus, the intention of tightening and loosening a package is detected using the first force sensor 16.1 and / or the second force sensor 20.1 which makes the use of the gripper 1 more intuitive and improves still the handling rate.

In a fifth embodiment shown in Figures 20 to 22, and unlike the third embodiment described above, only the first jaw 9 is powered by the second motor 84. The gripper 1 according to this fifth embodiment therefore does not include a third motor 85.

According to this fifth embodiment, the output shaft 84.1 of the second motor 84 is integral in rotation with a third pulley 9.1 and the second jaw 10 is integral in rotation with a fourth pulley 10.1. The upper end 6 of the first arm 5 comprises a fifth pulley 22 and a sixth pulley 23 rotatably mounted, around a second axis 022-23 substantially orthogonal to the first direction Ox, on either side of the frame 2. Thus the fifth pulley 22 is located on a front face

2.1 of the frame 2 and the sixth pulley 23 is located on a rear face 2.2 of the frame 2. In a homologous manner, the upper end 13 of the second arm 6 comprises a seventh pulley 24 and an eighth pulley 25 mounted for rotation, around a third axis 024-25 substantially orthogonal to the first direction Ox and parallel to the second direction 022-23, on either side of the frame 2. Thus the seventh pulley 24 is located on the front face 2.1 of the frame 2 and the eighth pulley 25 is located on the rear face 2.2 of the frame 2.

A ninth pulley 26.1 lower and a tenth pulley 26.2 upper are rotatably mounted on a support 27 along an axis substantially orthogonal to the first direction Ox and the second and third directions 022-23 and 024-25. The support 27 extends cantilevered from the frame 2 in a direction parallel to the first direction Ox.

The third pulley 9.1 and the fourth pulley 10.1 are double grooved pulleys. Thus, the third pulley 9.1 includes a first groove 9.11 and a second groove 9.12. The fourth pulley 10.1 includes a third groove 10.11 and a fourth groove 10.12. The ninth pulley 26.1 includes a fifth groove 26.11 lower and the tenth pulley 26.2 a sixth groove 26.12 upper.

A third cable 28 cooperates with the first groove 9.11 of the third pulley 9.1 and includes a first end 28.1 crimped in the first groove 9.11. The third cable 28 extends parallel to the first arm 5 on the front face 2.1 of the frame 2 to cooperate with the fifth pulley 22 which returns the third cable 28 to the sixth groove 26.12 of the tenth pulley 26.2. The third cable 28 then extends, at the outlet of the sixth groove 26.12, on the rear face 2.2 of the frame 2, parallel to the first direction Ox and joins the eighth pulley 25. The eighth pulley 25 returns the third cable 28 to the third groove 10.11 of the fourth pulley 10.1 in which the second end 28.2 of the third cable 28 is crimped.

A fourth cable 29 cooperates with the fourth groove 10.12 of the fourth pulley

10.1 and includes a first end 29.1 set in the fourth groove 10.12. The fourth cable 29 extends parallel to the second arm 6 on the front face 2.1 of the frame 2 to cooperate with the seventh pulley 24 which returns the fourth cable 29 in a direction parallel to the first direction Ox towards the fifth groove 26.11 of the ninth pulley 26. At the outlet of the fifth groove 26.11, the fourth cable 29 cooperates with the sixth pulley 23 which returns the fourth cable 29 to the second groove 9.12 of the pulley 9.1 in which the second end 29.2 of the fourth cable 29 is crimped.

Thus, a rotation of the output shaft 84.1 of the second motor 84 causes a rotation of the first jaw 9, the rotation of the output shaft 84.1 is transmitted by the third cable 28.1 and the fourth cable 29 to the fourth pulley 10.1 which causes the second jaw 10 to rotate in the same direction as that of the first jaw 9.

As illustrated in FIGS. 21 and 22, a translation of the first arm 5 and of the second arm 6 in the first direction Ox has no effect on the rotation of the first jaws 9 and second jaws 10.

Obviously, the invention is not limited to the embodiments described but encompasses any variant coming within the scope of the invention as defined by the claims.

In particular, although the gripper is here mounted at the end of an articulated arm with six motorized axes, the invention also applies to other types of load balancer, active or passive, such as for example a passive load balancer of the deformable parallelogram type with counterweight, or an active load balancer comprising a lower number of degrees of freedom such as for example a motorized vertical lifting winch on a trolley;

- although here the frame comprises a rectangular steel tube, the invention also applies to other types of frame such as for example a tube of circular, square or arbitrary section, a T or U profile, ferrous materials such as iron, stainless or non-ferrous steel such as copper, zinc, wood or any synthetic material;

- Although here the gripper comprises a T-rail cooperating with two PTFE pads of the first and / or second arm, the invention also applies to other means of sliding mounting of the arms on the frame such as for example track rollers engaged in rails, a single pad or more than two cooperating with other types of profiles or a ball or roller track;

- although the jaws here are identical and include a circular non-slip rubber plate, the invention also applies to other types of specific or universal jaws such as, for example, reel handling routers, claws for balls of wood or curved pliers for barrels. The first and second jaws can be the same or different;

- Although here the position of the first and second handles is adjustable by sliding on a rail and blocked by a clamping eccentric, the invention also applies to other means for adjusting the position of the first handle as by example a pin secured to the handle and engaged in perforations of the first or second arm;

- although here the handle is sliding on a guide extending perpendicular to a direction of the clamping force, the invention also applies to other degrees of adjustment of the handle relative to the frame as for example an adjustment in a direction orthogonal to a plane comprising the direction of the clamping force and one of the arms of the gripper; although here the clamping bar is integral with the upper end of the arm and extends in the sliding direction, the invention also applies to other implantations of the clamping bar on the arm such as for example at middle or lower part. The clamping bar can also extend in any direction, the passages in the bending tabs will then have to be adapted or other types of coupling means of the actuating unit with the bar will have to be implemented. (friction brake, magnet, rack);

although here the actuation unit comprises an electric motor, the invention also applies to other types of first actuator such as for example an electric pneumatic or hydraulic cylinder, a pneumatic or hydraulic motor;

although here the actuation unit comprises a belt and a toothed wheel secured to a screw, the invention applies to other means of coupling the first motor to the screw such as a direct drive, a smooth belt , a gear train;

although here the gripper comprises a first bracing cleat and a second bracing cleat, the invention also applies to other types of first and second controllable means for coupling the actuating unit such as for example an electromagnet, brake shoes, a dog clutch connection or a pinion / rack assembly; although here the arch pads include a parallelepiped body and two teeth, the invention also applies to other types of arch pads comprising a cylindrical body or any shape and or a single tooth facing a plane, teeth in the shape of a cylinder, triangle or square;

although here the arch pads are rotatably mounted in an anti-rotation tube, the invention also applies to a device without anti-rotation tube, this function being provided by the first and second passage arch pads;

although here the first free state of the skate corresponds to an inclination of its longitudinal axis of one hundred degrees relative to the axis Ox and that the second locked state of the skate corresponds to an inclination of its longitudinal axis substantially equal to eighty - ten degrees, the invention also applies to other values of inclination of the skate which may be a function of the dimensioning of the teeth and / or of the coefficients of friction of the pairs of materials used;

although here the distance between the end of the upper tooth and the lower tooth is substantially less than the height of the first clamping bar, the invention also applies to a distance separating the end of the upper tooth and of the tooth equal to or greater than the height of the first clamping bar. In this case the wedging angle will be less than, equal to or greater than ninety degrees;

although here the change of state of the pads as well as the application of a tightening force are ensured by the actuating unit, the invention also applies to a gripper in which the coupling of the unit actuation to the clamping bars is assigned to an actuator separate from the actuation unit such as for example a magnetic coupling;

although here the gripper includes a square to limit the movement of the first arm, the invention also applies to other types of stops such as elastomer blocks;

although here the tightening and loosening commands are carried out from a NO switch located on the first handle, the invention also applies to other types of trigger which may or may not be installed in the first handle, such as for example a selection joystick, contact sensors in the jaws or a voice command;

although here the force sensors are of piezometric types, the invention also applies to other types of force sensors such as for example a resistive strain gauge, an inductive or capacitive force sensor. The device can also be devoid of force sensor and the tightening / tightening be controlled by the operator;

although here the gripper has been described with a first force sensor on a first handle and a second force sensor on a second handle, the invention also applies to a single force sensor located on a single of the two handles or on an element linked to the handle or the arm; although here the control unit allows a delay of one second to elapse during which the torque of the first motor is measured as being zero before ceasing the instruction to rotate the first motor in the second direction, the invention also applies to different delay times such as less than one second or more than one second, as well as to other means of detecting a release of the package such as a camera, one or more pressure sensors located in the jaws or a trigger actuated by the operator;

although here the actuation unit comprises a second nut for tightening the flange against the toothed wheel, the invention also applies to other types of means for translating the first motor and the screw such as for example a pin through the screw or a fork;

although here the flange of the motor comprises a shaft pivotally mounted on the body of the second arch pad, the invention also applies to other means of linking the movement of the first motor and the second pad such as for example a rigid assembly by welding, a joint, a ball joint, an elastic connection;

although here the screw is a metric thread screw, the invention also applies to other types of screws such as for example a ball, roller, flat, round or square thread screw;

although here the actuation unit controls a stopping of the first motor (when the engine torque reaches a predetermined threshold value irreversible actuator), the invention also applies to an actuation unit controlling a maintenance of torque when the the actuator is a reversible actuator;

although here the screw includes a ball stop, the invention also applies to other types of stops allowing free rotation of the screw relative to the flange but blocking the relative translation of the flange and the screw, as for example a stop in graphite, or in bronze;

although here the change of state of the second controllable means for coupling the actuating unit and the second clamping bar are here controlled by the first actuator, the invention also applies to a device comprising a second arm clamp provided with a dedicated actuator, such as for example a second arm identical to the first and mounted symmetrically thereto, the second arm comprising a second screw and a second motor dedicated to act on the second arch pad; although here the gripper comprises a compression spring which extends parallel to the screw between the first arch pad and the second pad, the invention also applies to other means of promoting tilting skids such as an elastomer block, a magnetic attraction, a distribution of the masses of the arch pads. Such means are not essential to the invention insofar as in an inverted mounting of the clamping system, the tilting is done all by itself without spring under the effect of the dead weight of the hoof pads;

although here the gripper comprises a third cable and a fourth cable, the invention also applies to a single cable having a central anchorage connected to one of the third or fourth pulleys, the two end anchorages being connected to the other of the third or fourth pulley.

Claims (1)

Claims [Claim 1] Adjustable distance gripper (1) comprising: - a frame (2); - a first arm (5) slidably mounted on the frame (2) and provided with a first clamping jaw (9); - a second clamping jaw (10) linked to the frame; - a first clamping bar (30) integral with the first arm (5); - a first handle (16) connected to the first arm (5); - an actuation unit (31) for applying a clamping force between the first jaw (9) and the second jaw (10); - first controllable means of coupling (40) of the unit actuator (31) and the first clamping bar (30) which can selectively adopt a first state in which the relative movements of the actuating unit (31) and the first clamping bar (30) are free and a second state in which the actuation unit (31) applies a force to the first clamping bar (30). [Claim 2] Gripper (1) according to claim 1, in which the actuation unit (31) comprises a first actuator (32) and the change of state of the first controllable coupling means (40) is controlled by the first actuator (32 ). [Claim 3] Gripper (1) according to claim 1 or 2, wherein the actuating unit (31) comprises a screw (37). [Claim 4] Gripper (1) according to one of the preceding claims, in which the first controllable coupling means (40) comprise a first bracing shoe (40). [Claim 5] Gripper (1) according to claims 3 and 4 wherein the screw (37) collaborates with a nut (38) connected to the first bracing shoe (40). [Claim 6] Gripper (1) according to any one of the preceding claims, in which the first controllable coupling means (40) are connected to a trigger (50) integral with the first handle (16). [Claim 7] Gripper (1) according to any one of the preceding claims in which the position of the first handle (16) is adjustable in a direction substantially orthogonal to that of the tightening force. [Claim 8] Gripper (1) according to any one of the preceding claims, comprising a first adjustable stop (51) limiting the movement of the first arm (16). [Claim 9] Gripper (1) according to any one of claims 2 to 8, wherein the inertia of the first arm (5) does not include the inertia of the first actuator (32). [Claim 10] Gripper (1) according to any one of the preceding claims, in which the second clamping jaw (10) is integral with a second clamping arm (12) connected to a second handle (20), the second clamping arm ( 12) being slidably mounted on the frame (2) and the second clamping arm (12) being integral with a second clamping bar (60), the gripper (1) also comprising second controllable coupling means (70) the actuating unit (31) and the second clamping bar (60) to selectively adopt a third state in which the relative movements of the actuating unit (31) and the second clamping bar (60) are and a second state in which the actuating unit (31) applies a force to the second clamping bar (60). [Claim 11] Gripper (1) according to claims 2 and 10, wherein the change of state of the second controllable coupling means (70) is controlled by the first actuator (32). [Claim 12] Gripper (1) according to one of claims 10 or 11, wherein the second controllable coupling means (70) comprises a second bracing shoe (70). [Claim 13] Gripper (1) according to one of claims 10 to 12, wherein the actuating unit (31) comprises a first motor (32) linked to the second arch pad (70) for moving with the second pad d arch (70). [Claim 14] Gripper (1) according to any one of claims 10 to 13, wherein the position of the second handle (20) is adjustable in a direction substantially orthogonal to that of the clamping force. [Claim 15] Gripper (1) according to any one of claims 10 to 14, comprising a device for associating (90) the displacements of the first arm (5) and the second arm (12) arranged to cause a displacement of one of the first and second arm (5, 12) when the other of the first and second arms (5, 12) is moved. [Claim 16] Gripper (1) according to claim 15, wherein the association device (90) comprises a first pulley (91) rotatably mounted on the frame (2) and a second pulley (92) rotatably mounted on the frame (2 ), a first cable (93) cooperating with the first pulley (91) [Claim 17] [Claim 18] [Claim 19] [Claim 20] [Claim 21] [Claim 22] [Claim 23] [Claim 24] has a first end (93.1) integral with the first arm (5) and a second end (93.2) secured to the second arm (12), a second cable (94) cooperating with the second pulley (92) has a third end (94.1) secured to the first arm (5) and a fourth end secured (94.2) to the second arm (12). Gripper (1) according to any one of the preceding claims, comprising at least one motor (84, 85) for rotating the first jaw (9) and / or the second jaw (10). Gripper (1) according to claim 17, wherein a coupling device rotates the first jaw (9) and the second jaw (10). Gripper (1) according to any one of claims 10 to 16, in which the actuation unit (31) is controlled by a force sensor (20.1) located in the second handle (20). Gripper (1) according to any one of the preceding claims, in which the actuation unit (31) is controlled by a force sensor (16.1) located in the first handle (16). Gripper (1) according to any one of claims 2 to 20, wherein the inertia of the first arm (5) and / or the second arm does not include the inertia of the actuator (32). Handling device comprising a gripper (1) according to any one of the preceding claims. Handling device according to claim 22, comprising a passive load balancer. Handling device according to claim 22 or 23, comprising an active load balancer (80).