A tool changing arm, tool changing mechanism and tool changing method thereof

Abstract

The present invention relates to the technical field of tool changing mechanism structure, and in particular to a tool changing arm, a tool changing mechanism and a tool changing method thereof, comprising: a tool arm body; two clamping claw parts are arranged at both ends of the tool arm body, and the tool arm rotating shaft is arranged on the central axis of the tool arm body; the two clamping claw parts are bent around the rotating axis of the tool arm body in the same rotating direction to form a Z-shaped structure, and the semi-enclosed space surrounded by the clamping claw part and the tool arm body is used to accommodate the tool head, and the axis of the tool in the cutting edge is arranged perpendicular to the tool arm rotating shaft; the angle formed by the clamping claw part and the tool arm body facing the tool side is a right angle or an obtuse angle. The tool changing arm is arranged in a Z-shaped structure, and the tool changing arm can effectively utilize space in the vertical and horizontal directions, realize efficient operation in a limited space, reduce the interference between the tool changing arm and other parts of the machine tool, avoid possible collisions during the tool changing process, and adjust the angle between the clamping claw part and the tool arm body to adapt to tools of different diameters.

Description

Technical Field

[0001] The present invention relates to the technical field of tool changing mechanism structures, and in particular to a tool changing arm, a tool changing mechanism and a tool changing method thereof. Background Art

[0002] The tool changing mechanism is an important part of the CNC machining center. Its main function is to automatically change the tool during the machining process to meet the needs of different machining procedures. The tool changing arm plays a vital role in the tool changing mechanism. It is responsible for taking the tool out of the tool magazine and accurately installing it on the spindle during the machining process, or removing the tool on the spindle and putting it back into the tool magazine.

[0003] In the prior art, two knife claws are symmetrically provided at both ends of the tool changing arm, and the knife taking operation is realized through a series of actions such as unlocking the knife claws, translating to lock the knife, locking the knife claws and pulling out the knife. After the knife claws on one side have completed the knife taking, the tool changing arm will rotate through the knife arm shaft to move the active knife claw originally in the knife taking position to the knife placing position (such as an empty space in the tool magazine), thereby performing the knife returning operation of the tool in the knife claw on the other side.

[0004] However, since the two claws of the tool changing arm are symmetrically arranged, and the tool grasped in the claws is parallel to the axis of the tool arm's rotating shaft, when changing large-size tools, it is necessary to replace the tool changing arm with a longer arm length. This process may cause production interruptions, thereby affecting production efficiency. In addition, the longer tool changing arm occupies a larger space inside the machine tool, increasing the risk of collision with other machine tool components during the tool changing process, while limiting the spatial layout flexibility of the machine tool. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a tool changing arm, a tool changing mechanism and a tool changing method thereof, so as to effectively solve the problems in the background technology.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: a tool changing arm, comprising:

[0007] Blade arm body;

[0008] Two claw parts are arranged at both ends of the knife arm body, which include a knife clamp and two knife claws rotatably arranged inside the knife clamp; an arc-shaped clamping groove is arranged at one end of the knife clamp away from the knife arm body, and the ends of the two knife claws protrude from the knife clamp, and the inner arc groove of the protruding part forms a knife edge with the arc-shaped clamping groove for accommodating the knife handle of the knife;

[0009] A knife arm rotating shaft is arranged on the central axis of the knife arm body and is used to drive the knife arm body to rotate and change the knife;

[0010] The knife locking drive assembly comprises a knife locking shaft, a knife releasing plate and an elastic driving member arranged in the knife arm body, wherein the elastic driving member is arranged at one end of the knife locking shaft away from the clamping claw part to achieve locking of the knife, and the knife releasing plate is connected to the knife locking shaft to drive the knife locking shaft to move in a direction away from the clamping claw part to achieve unlocking of the knife;

[0011] The two clamping claw parts are bent around the rotation axis of the knife arm body toward the same rotation direction to form a Z-shaped structure, the semi-enclosed space surrounded by the clamping claw part and the knife arm body is used to accommodate the knife head of the knife, and the axis of the knife in the knife edge is arranged perpendicular to the knife arm rotation axis;

[0012] The angle formed by the claw part and the side of the knife arm body facing the knife tool is a right angle or an obtuse angle.

[0013] Furthermore, the knife locking drive assembly further comprises an auxiliary support rod; the auxiliary support rod is arranged on opposite surfaces of the two knife claws, the knife locking shaft is located between the two auxiliary support rods, and the two auxiliary support rods are symmetrically arranged relative to the axis of the knife locking shaft;

[0014] The knife arm body is provided with through holes corresponding to the two clamping claws for installing the knife locking shaft, and a sliding groove connected to the through hole is provided below the through hole, the knife loosening plate is arranged in the sliding groove, and one end of the knife loosening plate extending into the through hole is connected to the knife locking shaft;

[0015] When locking, the elastic driving member drives the knife locking shaft to extend between the two knife claws, so that the two auxiliary support rods move in a direction away from each other, so that the two knife claws grasp the knife;

[0016] When unlocking, the knife release plate is acted upon by an external force and moves in the sliding groove in a direction away from the clamping claw portion, thereby synchronously driving the knife locking shaft to move and compressing the elastic driving member so that the two knife claws release the knife.

[0017] Furthermore, the relative end faces of the two auxiliary support rods are inclined toward the direction of the knife locking shaft, and the distance between the two inclined end faces gradually increases toward the direction of the knife locking shaft, forming a gradual push hole for the knife locking shaft to enter.

[0018] Furthermore, the end of the knife locking shaft is provided with at least one conical surface;

[0019] A pre-locking shaft section is provided at the end of the tool locking shaft close to the tool clamp; and the taper of the pre-locking shaft section is smaller than the taper of the adjacent conical surface.

[0020] Furthermore, planar grooves communicating with the arc-shaped grooves are provided on both sides of the tool holder, and the two planar grooves are located in the same plane, and the two knife claws are symmetrically arranged in the two planar grooves in the tool holder;

[0021] The two ends of the knife clamp close to the arc-shaped slot are provided with hinge shafts, and there is a gap between the inner plane of the knife claw located between the inner arc slot and the auxiliary support rod and the bottom of the plane slot, and the knife claw is rotatably arranged in the plane slot through the hinge shaft;

[0022] Wherein, the knife clamp is provided with a limit pin at one end close to the knife arm body and corresponding to the end positions of the two knife claws, and the knife claw is provided with a step groove at the outer corner of one end close to the limit pin, and the limit pin is placed in the step groove;

[0023] When the knife is locked, the knife locking shaft drives the two auxiliary support rods to move in directions away from each other, and when the two knife claws clamp the knife, the limit pin abuts against the step surface of the step groove.

[0024] Furthermore, the end of the knife clamp close to one side of the knife arm shaft extends along the opening direction of the knife clip opening to form a support portion, and the support portion is lower than the end of the knife claw;

[0025] The inner arc surface of the support portion and the arc surface of the arc-shaped slot are arranged concentrically, and the vertical distance H from the end of the support portion to the bottom of the arc-shaped slot is equal to the radius R of the arc where the buckle edge is located.

[0026] Furthermore, the tool changing arm further comprises an elastic tool locking assembly, which is arranged inside the tool clamp and between the two tool claws, and is used to support the middle position of the tool claws;

[0027] The elastic knife locking assembly comprises two elastic plungers arranged corresponding to the two knife claws, and a middle dividing plate arranged between the two elastic plungers;

[0028] Wherein, the elastic plunger includes an outer sleeve, a push rod and a spring, the outer sleeve is screwed into the inner hole of the tool holder, the push rod is coaxially arranged in the outer sleeve, and an annular step is provided on the push rod, the spring is sleeved on the push rod, and is located between the annular step and the middle dividing plate.

[0029] Furthermore, the middle dividing plate is provided with a pressure sensing sheet on one side facing the two push rods.

[0030] The present invention also provides a tool changing mechanism, comprising:

[0031] ontology;

[0032] and a tool changing arm as described above, arranged above the body;

[0033] and a rotation drive assembly connected to the tool arm rotating shaft and used to drive the tool changing arm to rotate and change tools;

[0034] and a knife-drawing driving assembly disposed below the body and used for driving the body to move so as to drive the knife-changing arm to draw the knife;

[0035] and a translational knife-locking assembly disposed below the knife-drawing drive assembly;

[0036] And a knife arm loosening block used for applying external force to the knife loosening plate.

[0037] The present invention also provides a tool changing method of the tool changing mechanism as described above, comprising the following steps:

[0038] Start the translational tool locking assembly to move the tool changing mechanism to the tool magazine tool changing position;

[0039] Start the knife-drawing drive assembly to move the body toward the tool. At the same time, the knife-releasing block of the knife arm applies external force to the knife-releasing plate. The knife-releasing plate drives the knife-locking shaft to move. The two knife claws lose the locking force on the tool, triggering the knife-releasing action.

[0040] The translational knife-locking assembly continues to move to complete the knife-locking action of the knife in the tool;

[0041] The knife-pulling drive assembly moves in the reverse direction, causing the body to move a distance away from the knife. The knife-releasing plate releases the external force, and the knife-releasing block of the knife arm stops applying force. The knife-locking shaft pushes the knife claws to close under the action of the elastic drive member, and the protruding part of the knife claws is inserted into the handle of the new knife to complete the knife locking.

[0042] The tool-drawing drive assembly causes the main body to continue to move, and pulls out the locked tool from the tool magazine, completing the tool-drawing action;

[0043] The translation tool locking assembly is started again to move the tool changing mechanism loaded with a new tool to the spindle tool changing position;

[0044] Start the rotary drive assembly to rotate the tool changing arm around the tool arm shaft to achieve spindle tool changing.

[0045] The beneficial effects of the present invention are as follows: by configuring the tool changing arm into a unique Z-shaped structure, the tool changing arm can effectively utilize space in the vertical and horizontal directions to achieve efficient operation within a limited space. This structure reduces the interference between the tool changing arm and other parts of the machine tool, helps to avoid possible collisions during the tool changing process, and when facing high-speed rotation or movement, the Z-shaped structure enhances the stability of the tool changing arm and reduces the risk of accidental tool dropping due to vibration. In addition, by adjusting the angle between the claw part and the tool arm body, the tool changing arm can adapt to tools of different diameters, thereby improving the practicality and flexibility of the tool changing arm. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 A top view of a tool changing arm in an embodiment of the present invention;

[0048] Figure 2 Schematic diagram of the isometric structure of the tool changing arm in an embodiment of the present invention;

[0049] Figure 3 for Figure 1 AA section cutaway view;

[0050] Figure 4 It is a structural schematic diagram of the claw part in an embodiment of the present invention;

[0051] Figure 5 A second structural schematic diagram of a tool changing arm in an embodiment of the present invention;

[0052] Figure 6 Schematic diagram of the third structure of the tool changing arm in the embodiment of the present invention;

[0053] Figure 7 for Figure 3 A partial enlarged view of point B;

[0054] Figure 8 This is a schematic diagram of the structure of the knife locking shaft in an embodiment of the present invention;

[0055] Fig. 9 It is a schematic diagram of the structural decomposition of the claw part in an embodiment of the present invention;

[0056] Fig.10 Schematic diagram of the positional relationship of the support portion relative to the claw in an embodiment of the present invention;

[0057] Fig.11 This is a schematic diagram of the installation of the elastic knife locking assembly in the knife clamp according to an embodiment of the present invention;

[0058] Fig.12 Schematic diagram of the positions of the two knife claws when locked in an embodiment of the present invention;

[0059] Fig.13 Schematic diagram of the positions of the elastic knife locking assembly and two knife claws when unlocking in an embodiment of the present invention;

[0060] Fig.14 Schematic diagram of the positions of two knife claws when the knife enters the knife edge in the embodiment of the present invention;

[0061] Fig.15 Schematic diagram of the structure of the tool changing mechanism in the embodiment of the present invention.

[0062] 1. Knife arm body; 2. Clamping claw part; 21. Knife clamp; 21a. Arc-shaped clamping groove; 21b. Plane groove; 21c. Articulated shaft; 21d. Limit pin; 21e. Support part; 22. Knife claw; 22a. Inner arc groove; 22b. Step groove; 3. Knife arm rotating shaft; 4. Knife locking drive assembly; 41. Knife locking shaft; 41a. Conical surface; 41b. Pre-locking shaft section; 42. Knife releasing plate; 43. Elastic driving member; 44. Auxiliary support rod; 5. Elastic knife locking assembly; 51. Elastic plunger; 511. Outer sleeve; 512. Push rod; 512a. Abutment step; 513. Spring; 52. Pressure sensing plate; 521. Strain gauge; 10. Rotation driving assembly; 20. Knife pulling drive assembly; 30. Translational knife locking assembly; 40. Knife arm knife releasing block. DETAILED DESCRIPTION

[0063] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0064] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0065] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0066] like Figures 1 to 6 The tool change arm shown includes a tool arm body 1, two clamping claw parts 2, a tool arm rotating shaft 3 and a tool locking drive assembly 4;

[0067] Two claw parts 2 are arranged at both ends of the knife arm body 1, and include a knife clamp 21 and two knife claws 22 rotatably arranged inside the knife clamp 21; an arc-shaped clamping groove 21a is arranged at one end of the knife clamp 21 away from the knife arm body 1, and the ends of the two knife claws 22 protrude from the knife clamp 21, and the inner arc groove 22a of the protruding part and the arc-shaped clamping groove 21a form a knife edge for accommodating the knife handle;

[0068] The knife arm rotating shaft 3 is arranged on the central axis of the knife arm body 1 and is used to drive the knife arm body 1 to rotate and change the knife;

[0069] The knife locking drive assembly 4 comprises a knife locking shaft 41, a knife releasing plate 42 and an elastic driving member 43 arranged in the knife arm body 1. The elastic driving member 43 is arranged at one end of the knife locking shaft 41 away from the claw part 2 to achieve locking of the knife. The knife releasing plate 42 is connected to the knife locking shaft 41 to drive the knife locking shaft 41 to move in a direction away from the claw part 2 to achieve unlocking of the knife.

[0070] Among them, the two claw parts 2 are bent in the same rotation direction around the rotation axis of the blade arm body 1 to form a Z-shaped structure. The semi-enclosed space surrounded by the claw part 2 and the blade arm body 1 is used to accommodate the tool head, and the axis of the tool in the cutting edge is arranged perpendicular to the blade arm rotation axis 3; the angle formed by the claw part 2 and the side of the blade arm body 1 facing the tool is a right angle or an obtuse angle.

[0071] In the present invention, the two claw parts 2 and the knife arm body 1 form a Z-shaped tool changing arm structure, and the knife arm rotating shaft 3 is arranged perpendicular to the axis of the tool in the knife edge. When the two claw parts 2 are parallel to each other and the angle formed with the knife arm body 1 is a right angle, the tool head part of the tool handle is parallel to the knife arm body 1 after the knife edge is locked; when the two claw parts 2 are parallel to each other and the angle formed with the knife arm body 1 is an obtuse angle, the tool head part is arranged at a certain angle with the knife arm body 1, which can meet the demand for large-diameter tools; and when one end of the two claw parts 2 is at a right angle to the knife arm body 1 and the other end is at an obtuse angle to the knife arm body 1, when faced with the situation that the diameter of the required tool head is larger, the appropriate claw part 2 can be flexibly selected to grab the large-diameter tool, effectively avoiding the collision of the large-diameter tool with the knife arm body 1 during the tool removal process. The present invention arranges the tool changing arm into a unique Z-shaped structure, so that the tool changing arm can effectively utilize space in the vertical and horizontal directions to achieve efficient operation in a limited space. This structure reduces the interference between the tool changing arm and other parts of the machine tool, helps to avoid possible collisions during the tool changing process, and when facing high-speed rotation or movement, the Z-shaped structure enhances the stability of the tool changing arm and reduces the risk of accidental tool dropping due to vibration. In addition, by adjusting the angle between the claw part 2 and the tool arm body 1, the tool changing arm can adapt to tools of different diameters, thereby improving the practicality and flexibility of the tool changing arm.

[0072] The knife lock drive assembly 4 of the present invention further includes an auxiliary support rod 44; Figure 7 As shown, the auxiliary support rod 44 is arranged on the opposite surface of the two knife claws 22, the knife locking shaft 41 is located between the two auxiliary support rods 44, and the two auxiliary support rods 44 are symmetrically arranged relative to the axis of the knife locking shaft 41; it can ensure that when the knife locking shaft 41 is driven, the two knife claws 22 can move synchronously at the same rotation angle to avoid tool positioning errors caused by inconsistent rotation; in addition, the knife arm body 1 is provided with a through hole for installing the knife locking shaft 41 corresponding to the two claw parts 2, and a sliding groove connected to the through hole is provided below the through hole, and the knife loosening plate 42 is arranged in the sliding groove, and the end of the knife loosening plate 42 extending into the through hole is connected to the knife locking shaft 41; through the design of the internal through hole and the sliding groove, the knife locking drive assembly 4 is integrated in the knife arm body 1, saving space, making the tool changing arm more compact, and the knife loosening plate 42 synchronously drives the knife locking shaft 41 to move, so that the knife locking shaft 41 acts on the two knife claws 22, which simplifies the mechanical operation of knife locking and loosening, and reduces the need for external complex mechanical structure;

[0073] During the process of taking out the knife, the specific action process of the knife locking drive assembly 4 is as follows: when locking, the elastic driving member 43 drives the knife locking shaft 41 to extend between the two knife claws 22, so that the two auxiliary support rods 44 move in a direction away from each other, so that the two knife claws 22 grasp the knife;

[0074] When unlocking, the knife release plate 42 is acted upon by an external force and moves in the sliding groove in a direction away from the claw portion 2, thereby simultaneously driving the knife locking shaft 41 to move and compressing the elastic driving member 43, so that the two knife claws 22 release the knife.

[0075] As a preferred embodiment of the above embodiment, the relative end faces of the two auxiliary support rods 44 are inclined toward the direction of the knife locking shaft 41, and the distance between the two inclined surfaces gradually increases toward the direction of the knife locking shaft 41, forming a gradual push hole for the knife locking shaft 41 to enter.

[0076] The design of the inclined surface allows the distance between the two inclined surfaces to increase when the locking tool shaft 41 enters, thereby increasing the clamping force on the tool and ensuring the stability of the tool during processing, while the progressive locking reduces the impact and vibration during the locking process.

[0077] In a preferred embodiment of the present invention, at least one conical surface 41a is provided at the end of the knife locking shaft 41. The conical surface 41a serves as a guide surface to help the knife locking shaft 41 automatically align when entering the knife claw 22, and guide the knife locking shaft 41 to enter smoothly. When the end of the knife locking shaft 41 is provided with multiple conical surfaces 41a in a direction away from the tool holder 21, the taper of the multiple conical surfaces 41a gradually increases, so that when the knife locking shaft 41 gradually enters, the two knife claws 22 gradually lock the tool, thereby reducing tool damage caused by excessive or uneven locking force, such as Figure 8 As shown, in a preferred structure, a pre-locking shaft section 41 b is provided at the end of the tool locking shaft 41 close to the tool holder 21 ; and the taper of the pre-locking shaft section 41 b is smaller than the taper of the adjacent conical surface 41 a.

[0078] The pre-locking shaft section 41b serves as a guide for tool pre-positioning, helping the tool to perform preliminary alignment before entering the locking state, making the transition from the pre-locking shaft section 41b to the main locking area with a larger taper smoother, reducing impact and thus reducing the risk of damage to the tool.

[0079] In order to ensure the clamping reliability of the two knife claws 22 in the knife clamp 21, as shown in FIG. Fig. 9 As shown, a plane groove 21b connected to the arc groove 21a is provided on both sides of the knife clamp 21, and the two plane grooves 21b are located in the same plane, and two knife claws 22 are symmetrically arranged in the two plane grooves 21b in the knife clamp 21, and both ends of the knife clamp 21 close to the arc groove 21a are provided with hinge shafts 21c, and there is a gap between the inner plane of the knife claw 22 located between the inner arc groove 22a and the auxiliary support rod 44 and the bottom of the plane groove 21b, and the knife claw 22 is rotatably arranged in the plane groove 21b through the hinge shaft 21c;

[0080] The knife clamp 21 is provided with a stop pin 21d at one end close to the knife arm body 1 and corresponding to the end positions of the two knife claws 22, and the knife claw 22 is provided with a step groove 22b at the outer corner of one end close to the stop pin 21d, and the stop pin 21d is placed in the step groove 22b; when locking the knife, the knife locking shaft 41 drives the two auxiliary support rods 44 to move in a direction away from each other, and when the two knife claws 22 clamp the knife, the stop pin 21d abuts against the step surface of the step groove 22b. By setting the stop pin 21d and the step groove 22b, the knife edge can be controlled to ensure the locking response time of the knife claw 22 to the knife, thereby improving the response speed of the knife claw 22 when locking the knife.

[0081] like Fig.10 As shown, in the present invention, the end of the tool clamp 21 close to one side of the tool arm shaft 3 extends along the opening direction of the knife edge to form a support portion 21e, and the support portion 21e is lower than the end of the knife claw 22; the inner arc surface of the support portion 21e and the arc surface of the arc-shaped slot 21a are arranged concentrically, and the vertical distance H from the end of the support portion 21e to the bottom of the arc-shaped slot 21a is equal to the radius R of the arc where the knife edge is located.

[0082] When the tool enters the knife edge, the two knife claws 22 rotate synchronously to increase the entrance width of the knife edge. As the tool gradually enters, the tool handle will contact the support part 21e. At this time, the knife claw 22 located at the support part 21e stops rotating, and the support part 21e supports the bottom of the knife handle. The knife claw 22 on the opposite side will further rotate to adapt to the entry of the knife handle. The tool is clamped by the two knife claws 22 until the tool handle is completely in contact with the arc surface of the arc groove 21a, so that the tool can smoothly enter the knife edge.

[0083] In the present invention, the two knife claws 22 use the protruding parts to lock the tool in the knife-locking opening. When the knife-releasing plate 42 drives the knife-locking shaft 41 to move and release the knife, the ends of the two knife claws 22 away from the tool lose the pushing force. After the tool goes out of the knife-locking opening, the two knife claws 22 will continue to remain in the open state, causing the distance between the two knife claws 22 corresponding to the knife-locking shaft 41 to become smaller. When the knife needs to be taken out again, it will cause the knife-locking shaft 41 to be difficult to enter, affecting the smooth tool changing action of the tool changing arm. In addition, the large opening and closing angles of the two knife claws 22 will also increase the knife locking response time and affect the tool changing efficiency. Therefore, in order to ensure the feasibility of tool changing and further improve the tool changing efficiency, it is preferably, as Figure 11-14As shown, the tool changing arm further comprises an elastic tool locking assembly 5, which is arranged inside the tool holder 21 and between the two tool claws 22, and is used to support the middle position of the tool claws 22; so that the two tool claws 22 are kept in the best tool locking position, and the entering tool is pre-locked. Specifically, the elastic tool locking assembly 5 comprises two elastic plungers 51 arranged corresponding to the two tool claws 22, and an intermediate dividing plate arranged between the two elastic plungers 51; the two elastic plungers 51 are located on the same axis, and the intermediate dividing plate is arranged The middle demarcation plate is placed between the two elastic plungers 51. During the installation process, the middle demarcation plate will be inserted into the tool holder 21 from the side, and the two elastic plungers 51 are installed along the axial direction. Furthermore, the elastic plunger 51 includes an outer sleeve 511, a push rod 512 and a spring 513. The outer sleeve 511 is screwed into the inner hole of the tool holder 21. The push rod 512 is coaxially arranged in the outer sleeve 511, and an annular step is arranged on the push rod 512. The spring 513 is sleeved on the push rod 512 and is located between the annular step and the middle demarcation plate. One end of the spring 513 abuts against the middle demarcation plate, and the other end abuts against the annular step of the push rod 512, so that the push rod 512 can perform telescopic movement in the axial direction in the outer sleeve 511.

[0084] When the knife locking shaft 41 locks the two knife claws 22, the knife clamp 21 is in a horizontal state, and the springs 513 of the two elastic plungers 51 are in a compressed state; when the knife locking shaft 41 unlocks the two knife clamps 21, the elastic plunger 51 supports the two knife claws 22 to keep the two knife claws 22 in a horizontal state; the elastic plunger 51 puts the knife claws 22 in a floating state, and when the tool is taken out from the knife locking opening, the two knife claws 22 respectively apply downward pressure to the push rod 512 on the same side to move the push rod 512 downward, and as the tool is taken out from the knife locking openings of the two knife claws 22, the two knife claws 22 are restored to the horizontal state when the knife is locked under the reverse force of the elastic plunger 51; and when the knife needs to be taken out again, the knife claws 22 are acted on by the floating elastic plunger 51, and the tool enters smoothly. At the same time, the knife locking shaft 41 directly locks the two knife claws 22, shortening the knife locking response time of the knife claws 22 and improving the tool changing efficiency.

[0085] On the basis of the above embodiment, in order to ensure that the initial locking force of the two knife claws 22 is the same when the tool enters the knife edge, the middle dividing plate is provided with a pressure sensing sheet on the side facing the two push rods 512. During the installation of the elastic plunger 51, the installation depth of the outer sleeve 511 is controlled by the value of the pressure sensing sheet, and the rotation angle of the knife claw 22 is further controlled by the push rod 512, so as to effectively ensure the accuracy of the installation position of the elastic plunger 51 in the tool holder 21.

[0086] The present invention also provides a tool changing mechanism, such as Fig.15 As shown, the tool changing mechanism comprises: a body, and a tool changing arm arranged above the body;

[0087] and a rotation drive assembly 10 connected to the tool arm shaft 3 and used to drive the tool changing arm to rotate and change tools;

[0088] and a knife-drawing driving assembly 20 disposed below the body and used for driving the body to move so as to drive the knife-changing arm to draw the knife;

[0089] and a translational knife-locking assembly 30 disposed below the knife-drawing drive assembly 20;

[0090] And a knife arm loosening block 40 for applying external force to the knife loosening plate 42.

[0091] The tool changing mechanism utilizes a Z-type tool changing arm mechanism, which enhances the stability of the tool changing arm when facing high-speed rotation or movement, and reduces the risk of accidental tool dropping due to vibration.

[0092] The present invention also provides a tool changing method of a tool changing mechanism, comprising the following steps:

[0093] Start the translational tool locking assembly 30 to move the tool changing mechanism to the tool magazine tool changing position;

[0094] The knife-drawing drive assembly 20 is started to move the body toward the knife. At the same time, the knife arm knife-releasing block 40 applies an external force to the knife-releasing plate 42. The knife-releasing plate 42 drives the knife-locking shaft 41 to move. The two knife claws 22 lose the locking force on the knife, triggering the knife-releasing action.

[0095] The translational knife-locking assembly 30 continues to move to complete the knife-locking action of the knife in the tool;

[0096] The knife-drawing drive assembly 20 moves in the reverse direction, causing the body to move a distance away from the knife. The knife-releasing plate 42 releases the external force, and the knife-releasing block 40 of the knife arm stops applying force. The knife-locking shaft 41 pushes the knife claw 22 to close under the action of the elastic driving member 43, and the protruding part of the knife claw 22 is inserted into the handle of the new knife to complete the knife locking.

[0097] The knife-drawing driving assembly 20 causes the body to continue to move, and pulls out the locked knife from the tool magazine, completing the knife-drawing action;

[0098] The translational tool-locking assembly 30 is started again to move the tool-changing mechanism loaded with a new tool to the spindle tool-changing position;

[0099] The rotary drive assembly 10 is started to rotate the tool changing arm around the tool arm rotating shaft 3 to realize the spindle tool changing.

[0100] Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A tool changing arm, characterized in that: include: Blade arm body (1); Two clamping claw parts (2) are arranged at two ends of the knife arm body (1), and include a knife clamp (21) and two knife claws (22) rotatably arranged inside the knife clamp (21); an arc-shaped clamping groove (21a) is provided at one end of the knife clamp (21) away from the knife arm body (1), and the ends of the two knife claws (22) protrude from the knife clamp (21), and the inner arc groove (22a) of the protruding part and the arc-shaped clamping groove (21a) form a knife edge for accommodating a knife handle; A knife arm rotating shaft (3) is arranged on the central axis of the knife arm body (1) and is used to drive the knife arm body (1) to rotate and change knives; A knife locking drive assembly (4) comprises a knife locking shaft (41), a knife releasing plate (42) and an elastic driving member (43) arranged in the knife arm body (1); the elastic driving member (43) is arranged at one end of the knife locking shaft (41) away from the clamping claw part (2) to achieve locking of the knife; the knife releasing plate (42) is connected to the knife locking shaft (41) to drive the knife locking shaft (41) to move in a direction away from the clamping claw part (2) to achieve unlocking of the knife; The two clamping claw parts (2) are bent around the rotation axis of the knife arm body (1) toward the same rotation direction to form a Z-shaped structure, and the semi-enclosed space surrounded by the clamping claw parts (2) and the knife arm body (1) is used to accommodate the knife head of the knife, and the axis of the knife in the knife edge is arranged perpendicular to the knife arm rotation axis (3); The angle formed by the claw portion (2) and the side of the knife arm (1) facing the knife is a right angle or an obtuse angle; The knife locking drive assembly (4) further comprises an auxiliary support rod (44); The auxiliary support rod (44) is arranged on opposite surfaces of the two knife claws (22), the knife locking shaft (41) is located between the two auxiliary support rods (44), and the two auxiliary support rods (44) are symmetrically arranged relative to the axis of the knife locking shaft (41); The knife arm body (1) is provided with through holes corresponding to the two clamping claw parts (2) for installing the knife locking shaft (41), and a sliding groove connected to the through hole is provided below the through hole, the knife loosening plate (42) is arranged in the sliding groove, and one end of the knife loosening plate (42) extending into the through hole is connected to the knife locking shaft (41); When locking, the elastic driving member (43) drives the knife locking shaft (41) to extend between the two knife claws (22), so that the two auxiliary support rods (44) move in a direction away from each other, so that the two knife claws (22) grasp the knife; When unlocking, the knife release plate (42) is acted upon by an external force and moves in the sliding groove in a direction away from the clamping claw portion (2), thereby synchronously driving the knife locking shaft (41) to move and compressing the elastic driving member (43) so that the two knife claws (22) release the knife; The opposite end faces of the two auxiliary support rods (44) are arranged to be inclined toward the direction of the knife locking shaft (41), and the distance between the two inclined end faces gradually increases toward the direction of the knife locking shaft (41), forming a gradual push hole for the knife locking shaft (41) to enter.

2. The tool changing arm according to claim 1, characterized in that: The end of the knife locking shaft (41) is provided with at least one conical surface (41a); A pre-locking shaft section (41b) is provided at the end of the tool locking shaft (41) close to the tool clamp (21); and the taper of the pre-locking shaft section (41b) is smaller than the taper of the adjacent conical surface (41a).

3. The tool changing arm according to claim 1, characterized in that: Planar grooves (21b) communicating with the arc-shaped grooves (21a) are provided on both sides of the tool holder (21), and the two planar grooves (21b) are located in the same plane, and the two knife claws (22) are symmetrically arranged in the two planar grooves (21b) in the tool holder (21); The two ends of the knife clamp (21) close to the arc-shaped slot (21a) are both provided with hinge shafts (21c); the inner plane of the knife claw (22) located between the inner arc slot (22a) and the auxiliary support rod (44) has a gap with the bottom of the plane slot (21b); the knife claw (22) is rotatably arranged in the plane slot (21b) via the hinge shaft (21c); The knife clamp (21) is provided with a limit pin (21d) at one end close to the knife arm body (1) and corresponding to the end positions of the two knife claws (22); the knife claws (22) are provided with a step groove (22b) at the outer corner of one end close to the limit pin (21d), and the limit pin (21d) is placed in the step groove (22b); When the knife is locked, the knife locking shaft (41) drives the two auxiliary support rods (44) to move in directions away from each other, and when the two knife claws (22) clamp the knife, the limit pin (21d) abuts against the step surface of the step groove (22b).

4. The tool changing arm according to claim 1, characterized in that: An end portion of the knife clamp (21) close to one side of the knife arm rotation axis extends along the opening direction of the knife clip opening to form a support portion (21e), and the support portion (21e) is lower than the end portion of the knife claw (22); The inner arc surface of the support portion (21e) and the arc surface of the arc-shaped clamping groove (21a) are arranged concentrically, and the vertical distance H from the end of the support portion (21e) to the bottom of the arc-shaped clamping groove (21a) is equal to the radius R of the arc where the buckle edge is located.

5. The tool changing arm according to claim 1, characterized in that: The tool changing arm further comprises an elastic tool locking assembly (5), wherein the elastic tool locking assembly (5) is arranged inside the tool clamp (21) and between the two tool claws (22), and is used for supporting the middle position of the tool claws (22); The elastic knife locking assembly (5) comprises two elastic plungers (51) arranged corresponding to the two knife claws (22), and a middle dividing plate arranged between the two elastic plungers (51); Wherein, the elastic plunger (51) includes an outer sleeve (511), a push rod (512) and a spring (513); the outer sleeve (511) is screwed into the inner hole of the tool holder (21); the push rod (512) is coaxially arranged in the outer sleeve (511), and an annular step is provided on the push rod (512); the spring (513) is sleeved on the push rod (512) and is located between the annular step and the middle dividing plate.

6. The tool changing arm according to claim 5, characterized in that: The middle dividing plate is provided with a pressure sensing sheet on one side facing the two push rods (512).

7. A tool changing mechanism, characterized in that: include: ontology; and a tool changing arm as claimed in any one of claims 1 to 6, arranged above the body; and a rotation drive assembly (10) connected to the tool arm rotating shaft (3) and used for driving the tool changing arm to rotate and change tools; and a knife-drawing driving assembly (20) arranged below the body and used for driving the body to move so as to drive the knife-changing arm to draw the knife; and a translational knife-locking assembly (30) arranged below the knife-drawing drive assembly (20); And a knife arm loosening block (40) for applying external force to the knife loosening plate (42).

8. A tool changing method of the tool changing mechanism according to claim 7, characterized in that: The following steps are involved: Starting the translational tool locking assembly (30) to move the tool changing mechanism to the tool magazine tool changing position; The knife-drawing drive assembly (20) is started to move the body toward the direction of the knife. At the same time, the knife arm knife-releasing block (40) applies an external force to the knife-releasing plate (42). The knife-releasing plate (42) drives the knife-locking shaft (41) to move. The two knife claws (22) lose the locking force on the knife, triggering the knife-releasing action. The translational knife-locking assembly (30) continues to move to complete the knife-locking action on the knife in the tool; The knife-drawing drive assembly (20) moves in the reverse direction, causing the body to move a certain distance away from the knife, the knife-releasing plate (42) releases the external force, the knife-releasing block (40) of the knife arm stops applying force, and the knife-locking shaft (41) pushes the knife claw (22) to close under the action of the elastic driving member (43), and the protruding part of the knife claw (22) is inserted into the handle of the new knife to complete the knife locking; The knife-drawing driving assembly (20) causes the main body to continue to move, and pulls out the locked knife from the knife magazine, thus completing the knife-drawing action; The translational tool-locking assembly (30) is started again to move the tool-changing mechanism loaded with a new tool to the spindle tool-changing position; The rotary drive assembly (10) is started to rotate the tool changing arm around the tool arm rotating shaft (3) to realize the spindle tool changing.

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