Parallel-type gripper of robot arm

Abstract

The present invention relates to a parallel-type gripper of a robot arm and, more specifically, to a parallel-type gripper of a robot arm, which can perform eccentric gripping on the basis of the center line of the robot arm and movement of the gripper only in a direction perpendicular to the center line of an object, and can maximize the gripping force by minimizing a link length by means of a double 4-bar linkage configuration.

Description

Parallel gripper for robot arm

[0001] The present invention relates to a parallel gripper of a robot arm capable of gripping an object without collision with a surrounding structure and maximizing gripping force for the same driving force.

[0002] With the advancement of industrial automation and robotics, various types of robot grippers are being developed. Grippers are the end-effectors of robots, performing the functions of grasping, moving, and manipulating objects. The design and performance of grippers significantly impact the overall efficiency and usability of robotic systems, and therefore, research and development in this area are continuously ongoing.

[0003] Parallel robot grippers are one type of gripper, possessing a structure that grasps objects using two or more gripping sections arranged in parallel. Due to their structural characteristics, parallel grippers offer high rigidity and precision, and can apply uniform force, making them widely used in various industrial applications.

[0004] In addition, the parallel robot gripper has high precision and rigidity that enables high-precision work due to the parallel structure of the gripping part, so it has an advantage in applications that require precision assembly work or fine manipulation, and since the gripping parts arranged in parallel can transmit the same force to the object, it has the advantage of being able to stably hold sensitive objects or objects with irregular shapes.

[0005] The above-mentioned parallel gripper has a four-section mechanism and its composite form as shown in Fig. 1, or has a form utilizing a linear guide as shown in Fig. 2.

[0006] At this time, the parallel gripper of the 4-section mechanism type can create a larger stroke range compared to the mechanical size compared to the linear type parallel gripper illustrated in Fig. 2, and thus can be applied to various industrial fields such as manufacturing, assembly, and inspection.

[0007] Meanwhile, since the parallel gripper of the 4-section mechanism type has a driving mechanism that moves the moving trajectory of the gripping part not only in a direction perpendicular to the centerline of the object (in the direction of both sides of the object) but also in a direction horizontal to the centerline of the object (in the direction of the upper side of the object), as illustrated in Fig. 3a, it may cause a problem in that the ends of the fingers constituting the gripping part hit the floor on which the object is placed. In particular, the parallel gripper of the 4-section mechanism type has a problem in that an algorithm load is generated when an artificial intelligence algorithm is used to obtain a solution for gripping an object, in order to prevent the fingers from colliding with the floor.

[0008] In addition, the parallel gripper of the 4-section mechanism type was developed with the consideration of gripping objects placed in a wide work space, but the parallel gripper is actually used as a replacement for relatively narrow spaces (boxes, racks, etc.) where objects were previously transported by hand, such as in a logistics warehouse, and therefore has the problem of frequent collisions between the robot arm and surrounding structures.

[0009] For example, a parallel gripper is driven so that the fingers approach and grip the object in a direction perpendicular to the centerline of the object, that is, toward both sides of the object. However, when the robot arm approaches the object, it approaches only based on the criteria of matching the centerline between the object's centerline and the centerline between the fingers of the parallel gripper without considering interference from surrounding structures, which causes problems such as the robot arm hitting the edge of the opening of the box as shown in Fig. 3b.

[0010]

[0011] (Prior art literature)

[0012] (Patent Document)

[0013] (Patent Document 1) Republic of Korea Registration No. 10-2534804

[0014]

[0015] The purpose of the present invention is to provide a parallel gripper for a robot arm capable of eccentric gripping of the grip part with respect to the robot arm by making the center line of the object and the center line between the fingers coincide through independent movement of the grip part without movement of the robot arm when attempting to make the center line of the object and the center line between the fingers coincide for gripping the object.

[0016] Another object of the present invention is to provide a parallel gripper of a robot arm in which the trajectory of the fingers for gripping an object can be made only in a direction perpendicular to the center line of the object.

[0017] Another object of the present invention is to provide a parallel gripper for a robot arm that can maximize gripping force efficiency by minimizing the link length for creating a desired stroke.

[0018] In order to achieve the object of the present invention, the present invention provides a parallel gripper of a robot arm, comprising: a pair of driving units configured to independently generate power; a linkage having a plurality of joints; and fingers that are linked by the operation of the linkage, wherein the fingers are formed to face each other; a coupler link that is connected between the driving unit and the linkage and is formed to push or pull the linkage in a straight line with respect to the driving unit through the power of the driving unit; and a linear guide that is formed between the driving unit and the linkage and is configured to guide a linear reciprocating motion of the linkage, wherein the linkage is configured to convert the linear motion of the coupler link into a rotary motion and to open or close a gap between the fingers that are opposed to each other.

[0019] At this time, the pair of driving units may each include: a motor that generates rotational power; a main link having one end coupled to the shaft of the motor so as to rotate in the direction of movement of the linkage by the rotational power of the motor; and a driving pulley that is axially coupled between the other end of the main link and one end of the coupler link so as to perform rotational motion.

[0020] At this time, a driven pulley may be included that is axially coupled between the other end of the coupler link and the linkage to perform rotational motion.

[0021] At this time, a connecting member is connected between the driving pulley and the driven pulley, and the connecting member can be configured to transmit the rotational direction of the driving pulley to the driven pulley in the opposite direction.

[0022] At this time, the connecting member is made of a wire, and the wire can be connected in a twisted state between the driving pulley and the driven pulley.

[0023] In addition, the motor may be a right-angle motor arranged horizontally with respect to the coupler link.

[0024] In addition, the linkage may be formed of a 4-bar linkage, and the 4-bar linkage may be a double 4-bar linkage formed of a first 4-bar link forming one side of the linkage and a second 4-bar link forming the other side of the linkage.

[0025] At this time, the first 4-section link may include a first link formed on the linear guide; a second link axially coupled between the first link and the finger; a third link forming an end of the finger and axially coupled to the second link; and a fourth link axially coupled between the first link and the third link, and the second 4-section link may include a fifth link formed on the linear guide; a sixth link axially coupled between the fifth link and the finger; a seventh link forming an end of the finger and axially coupled to the sixth link; and an eighth link axially coupled between the fifth link and the seventh link.

[0026] At this time, the first link and the fifth link are fixed links, the second link is a driving link connected to the coupler link, and the third link, fourth link, sixth link, seventh link, and eighth link may be linkage links that are linked by the movement of the second link.

[0027] Additionally, the first link and the fifth link, the third link and the seventh link, and the fourth link and the eighth link may have the same configuration.

[0028] In addition, the first 4-section link and the second 4-section link may be arranged symmetrically on both sides of the linkage.

[0029] In addition, the linear guide may include a guide block having a slide hole formed on both sides in the direction of movement of the coupler link; and a pair of guide bars guided along the slide hole of the guide block.

[0030] At this time, the guide block is formed on both sides of the driving unit and forms a slide hole through both sides in the direction of movement of the coupler link, and the guide bar is formed as a pair that is guided along the slide hole of the guide block on both sides of the driving unit, and the linear guide may further form a connecting member that connects the ends of the pair of guide bars.

[0031] In addition, in the case where the center line of the object to be gripped and the center line between a pair of gripping units do not coincide, the parallel gripper of the robot arm of the present invention can be controlled to align the center line of the object and the center line between the gripping units through independent operation of each driving unit.

[0032] In addition, the parallel gripper of the robot arm of the present invention can be controlled so that when the driving unit operates to push the coupler link away from the driving unit, the linkage operates to separate a pair of fingers, and when the driving unit operates to pull the coupler link toward the driving unit, the linkage narrows the space between the pair of fingers and grips an object.

[0033] The effects of the present invention obtained through the above-described solution are as follows.

[0034] First, the present invention comprises a pair of motors generating independent power and a pair of gripping units independently controlled by each motor, thereby independently controlling each of the pair of gripping units so that the centerline between the pair of gripping units can be aligned with the centerline of the object without moving the robot arm. In other words, the pair of gripping units can perform eccentric gripping with respect to the robot arm.

[0035] Accordingly, the present invention has the effect of preventing collision between the robot arm and surrounding structures when gripping an object, since it can easily grip an object through a gripping unit without movement of the robot arm in a narrow space.

[0036] Second, the present invention can prevent collision between a structure on which an object is placed and a finger by ensuring that the trajectory of a gripping part for gripping an object is only in a direction perpendicular to the center line of the object, and can reduce the load of an algorithm for preventing collision of the finger, thereby providing an effect of providing a quick solution when using an eye-eye intelligence algorithm.

[0037] Third, the present invention configures the linkage as a 4-section link, and by configuring it as a double 4-section link arranged on both sides of the linkage, the rigidity of the linkage can be increased and there is an effect of not generating a singularity.

[0038] In particular, the double 4-section link of the present invention can minimize the link length for creating a desired stroke, thereby having the effect of maximizing the gripping force compared to the same driving force.

[0039] Fig. 1 is a drawing showing a parallel gripper of a 4-bar type according to the prior art.

[0040] Fig. 2 is a drawing showing a parallel gripper of a linear guide type according to the prior art.

[0041] Figure 3a is a drawing showing a problem in which a conventional parallel gripper hits a structure surrounding an object due to horizontal movement of the gripping portion during the process of gripping an object.

[0042] Figure 3b is a drawing showing a problem in which a conventional parallel gripper collides with a structure surrounding an object due to the movement of the robot arm during the process of gripping an object.

[0043] Fig. 4 is a perspective view showing a parallel gripper of a robot arm according to a preferred embodiment of the present invention.

[0044] FIG. 5 is a bottom perspective view showing a parallel gripper of a robot arm according to a preferred embodiment of the present invention.

[0045] Fig. 6 is a bottom view showing a parallel gripper of a robot arm according to a preferred embodiment of the present invention.

[0046] Fig. 7 is a plan view showing a parallel gripper of a robot arm according to a preferred embodiment of the present invention.

[0047] FIG. 8 is a perspective view showing a linkage composed of a double-joint link constituting a parallel gripper of a robot arm according to a preferred embodiment of the present invention.

[0048] FIG. 9 is a bottom perspective view showing a linkage composed of a double-joint link forming a parallel gripper of a robot arm according to a preferred embodiment of the present invention.

[0049] FIG. 10 is a plan view showing a linkage composed of a double-joint link that constitutes a parallel gripper of a robot arm according to a preferred embodiment of the present invention.

[0050] FIG. 11 is a bottom view showing a linkage composed of a double-joint link forming a parallel gripper of a robot arm according to a preferred embodiment of the present invention.

[0051] Figure 12 is a series of operation drawings sequentially showing the center gripping process of the parallel gripper of the robot arm according to a preferred embodiment of the present invention.

[0052] Figure 13 is a series of operation drawings sequentially showing the eccentric gripping process of the parallel gripper of the robot arm according to a preferred embodiment of the present invention.

[0053] FIG. 14 is a drawing showing stably gripping an object through vertical movement of a gripping portion constituting a parallel gripper of a robot arm according to a preferred embodiment of the present invention.

[0054] FIG. 15 is a drawing showing stably gripping an object in a box without moving the robot arm through independent driving of a gripping part constituting a parallel gripper of a robot arm according to a preferred embodiment of the present invention.

[0055] Below, the parallel gripper of the robot arm is described in more detail with reference to the drawings.

[0056] In describing the embodiments disclosed in this specification, if it is determined that a detailed description of a related known technology may obscure the gist of the embodiments disclosed in this specification, the detailed description is omitted.

[0057] The attached drawings are only intended to facilitate understanding of the embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the attached drawings, and should be understood to include all modifications, equivalents, or substitutes included in the spirit and technical scope of the present invention.

[0058] In the following description, singular expressions include plural expressions unless the context clearly indicates otherwise.

[0059] In this application, terms such as “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in the specification, but should be understood not to exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0060] Hereinafter, a parallel gripper of a robot arm according to a preferred embodiment of the present invention will be described with reference to the attached drawings 1 to 15.

[0061] The parallel gripper of the robot arm independently drives each pair of gripping parts, so that the center line between the pair of gripping parts can be freely adjusted to match the center line of the object without moving the robot arm.

[0062] In addition, the parallel gripper of the robot arm is configured with a gripping section of a 4-section link, but is configured with a double 4-section link so as not to generate a singularity, and can maximize gripping force efficiency by minimizing the link length.

[0063] The parallel gripper of the robot arm may include a driving unit (1000), a linear guide (2000), a gripping unit (3000), a driven pulley (4000), a coupler link (5000), and a connecting member (6000), as shown in FIGS. 4 and 5.

[0064] The driving unit (1000) generates power to drive the gripping unit (3000), and as the gripping units (3000) are configured as a pair, the driving units (1000) are also configured as a pair so that the gripping units (3000) can be driven independently.

[0065] The driving unit (1000) may be provided on the gripper body (B) for coupling with the robot arm, and a pair of driving units (1000) may be provided on both sides of one side of the gripper body (B) as illustrated in FIG. 5. At this time, one side of the gripper body (B) refers to the bottom surface of the gripper body (B) in the drawing.

[0066] The driving unit (1000) can generate rotational power and may include a motor (1100), a main link (1200), and a driving pulley (1300).

[0067] The motor (1100) generates rotational power and includes a motor shaft (1110) that is formed to protrude toward the other surface of the gripper body (B). That is, the motor shaft (1110) is formed in a direction perpendicular to the body of the motor (1100), and the present specification assumes that the motor (1100) is a right angle motor as an example.

[0068] The main link (1200) is formed to be able to rotate by the rotational power of the motor (1100) and is axially coupled to the motor shaft (1110). At this time, one end of the main link (1200) is coupled to the motor shaft (1110), and thus the main link (1200) can rotate around one end. That is, the main link (1200) can rotate clockwise or counterclockwise around one end by the forward and reverse rotation of the motor (1100).

[0069] The drive pulley (1300) is formed to be linked with the main link (1200) that rotates by the rotational power of the motor (1100), and is axially connected to the other end of the main link (1200).

[0070] The drive pulley (1300) has a groove formed on the outer surface in which a connecting member (6000) described later can be positioned, and a fixing projection (1310) can be formed to fix the end of the connecting member (6000).

[0071] Next, the linear guide (2000) serves to guide the gripper (3000) in a straight line when the gripper (3000) reciprocates due to the power of the driving unit (1000), and is formed at a position corresponding to each driving unit (1000).

[0072] Since the linear guide (2000) is composed of a pair of a driving unit (1000) and a grip unit (3000), it can be formed as a pair in the gripper body (B).

[0073] The linear guide (2000) may include a guide block (2100) and a guide bar (2200), as shown in FIGS. 4 to 6.

[0074] The guide block (2100) can be formed on both sides of the motor (1100) and can form a slide hole (2110) that penetrates in the movement direction of the grip part (3000).

[0075] The guide bar (2200) is provided on each guide block (2100) formed on both sides of the motor (1100), and may be formed in the form of a bar that can slide through the slide hole (2110).

[0076] Meanwhile, the linear guide (2000) further forms a connecting member (2300) that can integrate the guide bar (2200) provided in each guide block (2100), and the connecting member (2300) can connect the end of the guide bar (2200) on the gripping part (3000).

[0077] At this time, the connecting members (2300) formed on each linear guide (2000) can form a step at the overlapping portion so that the connecting members (2300) do not interfere with each other when the gripping part (3000) moves independently.

[0078] Next, the gripping unit (3000) is configured to approach from both sides of the object and grip both sides of the object, and is composed of a pair that are independently driven by the power of the driving unit (1000).

[0079] The gripper (3000) is formed so that it can only move perpendicularly to the center line of the object, and may include a linkage (3100) and a finger (3200).

[0080] The linkage (3100) has multiple joints and can be composed of multiple links that are linked around the joints.

[0081] At this time, the linkage (3100) is formed of a 4-section link, and is formed of a double 4-section link in which both sides of the linkage (3100) are formed of 4-section links. At this time, both sides of the linkage (3100) refer to the upper and lower parts of the linkage (3100) in the drawing, and as illustrated in FIGS. 8 to 11, the upper and lower parts of the linkage (3100) each form a 4-section link.

[0082] For convenience of explanation in this specification, the 4-section link forming the upper part of the linkage (3100) is referred to as the first 4-section link (3110), and the 4-section link forming the lower part of the linkage (3100) is referred to as the second 4-section link (3120).

[0083] The first 4-section link (3110) is composed of four links, and may be composed of a first link (3111), a second link (3112), a third link (3113), and a fourth link (3114).

[0084] The first link (3111) is a fixed link and is formed on the connecting member (2300) of the linear guide (2000), as shown in FIGS. 8 and 10.

[0085] The second link (3112) is a driving link that receives power from the driving unit (1000) and drives the linkage (3100), and is axially connected between the first link (3111) and the finger (3200).

[0086] The third link (3113) is a linkage that is linked to the fourth link (3114) by the driving of the second link (3112) while forming the end of the finger (3200), and is axially coupled to the second link (3112).

[0087] The fourth link (3114) is a linkage that is linked to the third link (3113) by the driving of the second link (3112), and is axially coupled between the first link (3111) and the third link (3113). At this time, the fourth link (3114) is formed so as not to interfere with the second link (3112). That is, the fourth link (3114), like the second link (3112), is axially coupled between the first link (3111) and the third link (3113), but as illustrated in FIG. 8, a height difference is formed vertically so as not to cause interference between them.

[0088] The second 4th link (3120) is also composed of four links, and may be composed of a fifth link (3121), a sixth link (3122), a seventh link (3123), and an eighth link (3124).

[0089] The fifth link (3121) is a fixed link and is formed on the connecting member (2300) of the linear guide (2000), as shown in FIGS. 9 and 11.

[0090] The sixth link (3122) is a linkage link that is linked when the second link (3112) is driven, and is axially coupled between the fifth link (3121) and the finger (3200).

[0091] The seventh link (3123) forms the end of the finger (3200), and is a linkage link that is linked with the sixth link (3122) and the eighth link (3124) by the driving of the second link (3112), and is axially coupled with the sixth link (3122).

[0092] The eighth link (3124) is a linkage that is linked with the sixth link (3122) and the seventh link (3123) by the driving of the second link (3112), and is axially coupled between the fifth link (3121) and the seventh link (3123). At this time, the eighth link (3124) is formed so as not to interfere with the sixth link (3122). That is, the eighth link (3124), like the sixth link (3122), is axially coupled between the fifth link (3121) and the seventh link (3123), but as illustrated in FIG. 9, a height difference is formed vertically so as not to cause interference between them.

[0093] As described above, the linkage (3100) of this configuration is formed as a double 4-section link in which the first 4-section link (3110) and the second 4-section link (3120) are formed symmetrically on both sides of the linkage (3100). At this time, the first link (3111) and the fifth link (3121), the third link (3113) and the seventh link (3123), and the fourth link (3114) and the eighth link (3124) are formed with the same configuration and can perform the roles of each other.

[0094] Accordingly, the double 4-section link configured as described above can reduce the number of parts, thereby lowering the manufacturing cost, and has the characteristic of increasing the rigidity of the linkage (3100).

[0095] In addition, the double 4-section link of the present invention can maximize the usable angle range of the linkage (3100) by preventing the occurrence of a structural singularity. That is, in the case of a single 4-section link, the gripper (3000) has difficulty performing its function due to the unstable structure between the linkage and the finger (3200) at a certain angle of the linkage (3100), so the usable range of the gripper (3000) may be limited in the case of a single 4-section link, but the double 4-section link does not cause a structural singularity, so it does not limit the usable range of the gripper (300).

[0096] For the above reasons, a single 4-section link can only be used in a range that does not generate a singularity, and in order to compensate for the limitation of the range of use, the length of the gripping part (3000) must be maximized. As a result, the single 4-section link has a problem in that the gripping force of the gripping part (3000) is reduced by the ratio of the length of the gripping part (3000) to the same driving force of the driving part (1000). On the other hand, a double 4-section link can minimize the length of the gripping part (3000) to create a desired stroke, and thus can maximize the gripping force of the gripping part (3000).

[0097] Next, the driven pulley (4000) receives power from the main link (1200) and drives the linkage (3100), and is axially connected to the second link (3112).

[0098] The driven pulley (4000) is formed in a circular shape with the same diameter as the driving pulley (1300), and can form a fixing projection (4100) for fixing the end of the connecting member (6000).

[0099] Next, the coupler link (5000) is a means for transmitting the power of the main link (1200) by the driving unit (1000) to the linkage (3100), and is connected between the driving pulley (1300) and the driven pulley (4000). The coupler link (5000) is made of a straight bar and is axially connected to the center of the driving pulley (1300) and the center of the driven pulley (4000).

[0100] In addition, the coupler link (5000) always maintains the same gap between the driving pulley (1300) and the driven pulley (4000), and transmits the movement of the main link (1200) according to the power of the driving unit (1000) to the linkage (3100). That is, the coupler link (5000) converts the rotational motion of the main link (1200) centered on the motor shaft (1110) into a linear motion that can push or pull the grip unit (3000) in a straight line.

[0101] In addition, the coupler link (5000) can always keep the tension of the connecting member (6000) described later constant by keeping the gap between the driving pulley (1300) and the driven pulley (4000) the same. If the coupler link (5000) is omitted, when the driving pulley (1300) and the driven pulley (4000) are spaced apart from each other by a large distance, and when the driving pulley (1300) and the driven pulley (4000) are brought close to each other, not only will there be a difference in the tension of the connecting member (6000), but especially when the driving pulley (1300) and the driven pulley (4000) are brought close to each other, the tension of the connecting member (6000) described later will loosen, making it impossible for the connecting member (6000) to perform its original function.

[0102] Therefore, the coupler link (5000) can always keep the tension of the connecting member (6000) constant by always keeping the gap between the driving pulley (1300) and the driven pulley (4000) constant.

[0103] Next, the connecting member (6000) serves to transmit the rotational direction of the driving pulley (1300) by the power of the driving unit (1000) in the opposite direction to the driven pulley (4000). That is, the connecting member (6000) transmits the rotational force of the driving pulley (1300) according to the rotation of the main link (1200) to the driven pulley (4000) in the opposite direction, so that the main link (1200) and the linkage (3100) can rotate in opposite directions while rotating the linkage (3100) within the length range of the coupler link (5000).

[0104] In addition, the connecting member (6000) serves to maintain the horizontality of the coupler link (5000) between the central axis of the driving pulley (1300) and the central axis of the driven pulley (4000), and can be provided in various forms.

[0105] For example, as an example of maintaining the central axis of the driving pulley (1300), the central axis of the driven pulley (4000), and the coupler link (5000) horizontal, it may be formed of any one of a wire pulley, a gear-pinion, a chain-spoke, and a belt pulley, and any configuration that allows the central axis of the driving pulley (1300), the central axis of the driven pulley (4000), and the coupler link (5000) to be horizontal is acceptable.

[0106] In this specification, the connection member (6000) is described as an example of a wire.

[0107] Both ends of the wire (6000) can be respectively fixed to the fixed projection (1310) of the driving pulley (1300) and the fixed projection (4100) of the driven pulley (4000).

[0108] At this time, the wire (6000) can be connected in a twisted state between the driving pulley (1300) and the driven pulley (4000) as shown in FIGS. 4 and 7. In this way, by connecting the wire (6000) in a twisted state between the driving pulley (1300) and the driven pulley (4000), the driving pulley (1300) and the driven pulley (4000) can perform rotational motion in opposite directions.

[0109] Hereinafter, the operation of the parallel gripper of the robot arm having the above-described configuration will be described.

[0110]

[0111] [Central Phage]

[0112] Referring to Figure 12, a series of processes for gripping an object by aligning the centerline of the object to be gripped with the centerline of the robot arm will be described. This type of center gripping method is advantageous when space is secured for the robot arm to move.

[0113] As shown in (a) of Fig. 12, a pair of gripping parts (3000) are aligned with the center line of the robot arm (R) at the same position, and the robot arm (R) is tilted toward one side of the object, so that the center line of the object and the gripping part (3000), or more precisely, the center line between the pair of fingers (3200), do not coincide.

[0114] Thereafter, the control unit moves the robot arm (R) to align the center line between the fingers (3200) with the center line of the object, as shown in (b).

[0115] Thereafter, the control unit drives the driving unit (1000) to widen the gap between a pair of fingers (3200) to a gap larger than the width of the object.

[0116] To this end, the driving unit (1000) rotates the motor (1100) to rotate the main link (1200A) on the upper side in the drawing clockwise and the main link (1200B) on the lower side counterclockwise. Accordingly, the coupler link (5000) moves to the right in the drawing by the rotation radius of the main link (1200), and moves the linear guide (2000) to the right in the drawing as shown in (b) and (c) of FIG. 12.

[0117] At this time, along with the movement of the linear guide (2000), the upper main link (1200A) rotates the drive pulley (1300) clockwise, and the lower main link (1200B) rotates the drive pulley (1300) counterclockwise. At this time, due to the rotation of the drive pulley (1300), the upper wire (6000A) rotates the upper driven pulley (4000A) counterclockwise, and the lower wire (6000B) rotates the lower driven pulley (4000B) clockwise. Accordingly, the upper driven link (4000A) rotates the second link (3112) of the upper linkage (3100A) counterclockwise, and the lower driven link (4000B) rotates the second link (3112) of the lower linkage (3100B) clockwise, thereby widening the gap between the fingers (3200), as shown in (b) and (c) of FIG. 12.

[0118] Thereafter, the control unit moves the robot arm (R) straight toward the object, positioning the object between a pair of fingers (3200), as shown in (d) of Fig. 12.

[0119] Thereafter, the control unit causes the driving unit (1000) to rotate the motor (1100) in the reverse direction, thereby rotating the upper main link (1200A) counterclockwise and rotating the lower main link (1200B) clockwise. Accordingly, the coupler link (5000) moves to the left in the drawing by the rotation radius of the main link (1200), thereby moving the linear guide (2000) as shown in (d) and (e) of FIG. 12.

[0120] At this time, along with the movement of the linear guide (2000), the upper main link (1200A) rotates the upper drive pulley (1300A) counterclockwise, and the lower main link (1200B) rotates the lower drive pulley (1300B) clockwise. At this time, the upper wire (6000A) rotates the upper driven pulley (4000A) clockwise, and the lower wire (6000B) rotates the lower driven pulley (4000B) counterclockwise.

[0121] Accordingly, the upper driven link (4000A) rotates the second link (3112) of the upper linkage (3100A) clockwise, and the lower driven link (4000B) rotates the second link (3112) of the lower linkage (3100B) counterclockwise, thereby gripping both sides of the object while narrowing the gap between the fingers (3200) perpendicular to the center line of the object, as shown in (e) of FIG. 12.

[0122] Afterwards, the control unit controls the robot arm (R) to move it to the transport location, thereby completing the central gripping task of the object.

[0123]

[0124] [Eccentric phagocytosis]

[0125] Referring to Fig. 13, a series of processes for gripping an object by aligning the center line of the gripping target object and the center line between the gripping part (3000), or more precisely, the center line between the fingers (3200), will be described.

[0126] This type of eccentric gripping method is advantageous in narrow spaces where it is difficult for the robot arm (R) to move. That is, unlike the 'center gripping' method in which the center line of the object and the center line between the fingers (3200) are aligned through the movement of the aforementioned robot arm (R), the 'eccentric gripping' method can grip an object only with the movement of the gripping part (3000) without the movement of the robot arm (R) through the independent driving of the gripping part (3000).

[0127] As shown in (a) of Fig. 13, the robot arm (R) is tilted to one side of the object, and the center line between the center line of the object and the gripper (3000), or more precisely, the center line between the center line of the object and the finger (3200), do not match.

[0128] Thereafter, the control unit drives the driving unit (1000) to align the center line between the fingers (3200) with the center line of the object, as shown in (b).

[0129] To this end, the driving unit (1000) on one side, for example, the motor (1100B) on the lower side in the drawing, is driven to rotate the main link (1200B) on the lower side in the counterclockwise direction. Accordingly, the coupler link (5000B) on the lower side moves to the right in the drawing by the rotation radius of the main link (1200B) on the lower side, and moves the linear guide (2000B) on the lower side to the right in the drawing as shown in (a) and (b) of FIG. 13.

[0130] At this time, along with the movement of the linear guide (2000B), the main link (1200B) on the lower side rotates the driving pulley (1300B) on the lower side counterclockwise, and the wire (6000B) on the lower side rotates the driven pulley (4000B) on the lower side clockwise. Accordingly, the driven link (4000B) on the lower side rotates the second link (3112) of the lower linkage (3100B), thereby rotating the lower linkage (3100B) clockwise, as illustrated in (b) of FIG. 13.

[0131] Accordingly, the lower finger (3200B) in the drawing moves away from the opposing upper finger (3200A), and eventually the center line between the fingers (3200) coincides with the center line of the object.

[0132] Thereafter, the control unit moves the robot arm (R) straight toward the object, positioning the object between a pair of fingers (3200), as shown in (c) of Fig. 13.

[0133] Thereafter, the control unit causes the driving unit (1000) to rotate the motor (1100) to rotate each main link (1200) clockwise or counterclockwise. Accordingly, the coupler link (5000) moves to the left in the drawing by the rotation radius of the main link (1200) and moves the linear guide (2000) as shown in (c) and (d) of FIG. 13.

[0134] At this time, along with the movement of the linear guide (2000), each main link (1200) rotates the driving pulley (1300) clockwise or counterclockwise, and each wire (6000) rotates the driven pulley (4000) counterclockwise or clockwise.

[0135] Accordingly, each driven link (4000) rotates the second link (3112) of each linkage (3100) counterclockwise or clockwise, and grips both sides of the object while narrowing the gap between the fingers (3200) perpendicular to the center line of the object, as shown in (d) of FIG. 13.

[0136] Afterwards, the control unit controls the robot arm (R) to move it to the transport location, thereby completing the eccentric gripping task of the object.

[0137] As described so far, the parallel gripper of the robot arm according to the present invention can prevent the finger (3200) from colliding with the structure around the object by performing the movement of the gripping part (3000) for gripping the object only in the direction perpendicular to the center line of the object, as shown in FIG. 14, and when applying the artificial intelligence algorithm, the algorithm in which the movement of the gripping part (3000) is performed in the horizontal direction with respect to the center line of the object can be omitted, thereby preventing the algorithm load.

[0138] In addition, since the present invention can drive a pair of gripping units (3000) through independent driving of the driving unit (1000), as illustrated in FIG. 15, an object can be gripped only with the independent movement of the gripping unit (3000) without movement of the robot arm (R). That is, since the present invention can grip an object eccentrically with respect to the center line of the robot arm (R), an object can be stably gripped even in a narrow space where the movement of the robot arm (R) is restricted.

Claims

1. A pair of driving units configured to independently generate power; A linkage having a plurality of joints, and a pair of fingers that are linked by the operation of the linkage, wherein the fingers are formed to face each other; A coupler link connected between the driving unit and the linkage, and formed so as to push or pull the linkage in a straight line based on the driving unit through the power of the driving unit; A linear guide formed between the driving unit and the linkage and configured to guide the linear reciprocating motion of the linkage, The above linkage is configured to widen or close the gap between the opposing fingers while converting the linear motion of the coupler link into rotational motion. Parallel gripper for robot arm.

2. In paragraph 1, The above pair of driving units are each, A motor that generates rotational power; A main link having one end coupled to the shaft of the motor so as to rotate in the direction of movement of the linkage by the rotational power of the motor; Including a drive pulley that is axially coupled between the other end of the main link and one end of the coupler link to perform rotational motion. Parallel gripper for robot arm.

3. In paragraph 2, Including a driven pulley that is axially coupled between the other end of the coupler link and the linkage to perform rotational motion. Parallel gripper for robot arm.

4. In paragraph 3, A connecting member is connected between the above driving pulley and the driven pulley, The above connecting member is configured to transmit the rotational direction of the driving pulley to the driven pulley in the opposite direction. Parallel links of a robot arm.

5. In paragraph 4, The above connecting member is made of a wire, and the wire is connected in a twisted state between the driving pulley and the driven pulley. Parallel links of a robot arm.

6. In paragraph 2, The above motor is a right-angle motor arranged horizontally with the coupler link. Parallel gripper for robot arm.

7. In paragraph 1, The above linkage is composed of a 4-bar linkage, and the 4-bar linkage is It is characterized by being a double 4-section link consisting of a first 4-section link constituting one side of the linkage and a second 4-section link constituting the other side of the linkage. Parallel gripper for robot arm.

8. In paragraph 7, The above Section 14 link is, A first link formed on the above linear guide; A second link axially coupled between the first link and the finger; A third link forming the end of the finger and axially coupled to the second link; A fourth link is included that is axially coupled between the first link and the third link, The above 2nd and 4th paragraph links, A fifth link formed on the above linear guide; A sixth link axially coupled between the fifth link and the finger; A seventh link forming the end of the above finger and axially coupled to the sixth link; Including an eighth link axially coupled between the fifth link and the seventh link, Parallel gripper for robot arm.

9. In paragraph 8, The above first link and the above fifth link are fixed links, The above second link is a driving link connected to the coupler link, The above third link, fourth link, sixth link, seventh link, and eighth link are interlocking links that are interlocked by the movement of the second link. Parallel gripper for robot arm.

10. In paragraph 8, The first link and the fifth link, the third link and the seventh link, the fourth link and the eighth link are formed with the same configuration. Parallel gripper for robot arm.

11. In paragraph 7, The above 1st 4th section link and the above 2nd 4th section link are arranged symmetrically on both sides of the linkage. Parallel gripper for robot arm.

12. In paragraph 1, The above linear guide, A guide block having a slide hole formed on both sides in the direction of movement of the above coupler link; A pair of guide bars including a pair of guide bars guided along the slide hole of the above guide block, Parallel gripper for robot arm.

13. In paragraph 12, The above guide block is formed on both sides of the driving unit, and forms a slide hole through both sides in the direction of movement of the coupler link, The above guide bars are formed as a pair that are guided along the slide holes of the guide blocks on both sides of the driving unit, The above linear guide further forms a connecting member connecting the ends of the pair of guide bars. Parallel gripper for robot arm.

14. In any one of paragraphs 1 to 13, When the center line of the object to be gripped and the center line between a pair of gripping parts do not coincide, the pair of gripping parts are controlled to coincide with the center line of the object and the center line between the gripping parts through independent operation of each driving unit. Parallel gripper for robot arm.

15. In paragraph 1, When the above driving unit operates to push the coupler link away from the driving unit, the linkage operates to separate a pair of fingers, When the above driving unit operates and pulls the coupler link toward the driving unit, the linkage is controlled to grip an object by narrowing the space between a pair of fingers. Parallel gripper for robot arm.

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