Nut and bolt feeding and positioning mechanism

Abstract

This utility model discloses a nut and bolt feeding and positioning mechanism, which includes an upper electrode assembly that can be floated and mounted on a machine base, and a feeding gun that can extend to the lower side of the upper electrode assembly. The upper electrode assembly includes a cylindrical upper electrode head, an adsorption column disposed within the upper electrode head, and a magnetic suction body disposed within the adsorption column. The feeding gun includes a gun frame, a feeding rod that is telescopically mounted on the gun frame, and a feeding hand connected to the feeding rod and that can be pushed to the lower side of the upper electrode head. When the adsorption column with the magnetic suction body needs to adsorb bolt / nut workpieces, it extends out from the inner hole of the upper electrode head or stops inside the upper electrode head and is flush with its lower end face. The feeding rod delivers the feeding hand carrying the workpiece to the lower side of the upper electrode head. The magnetic suction body attracts the workpiece to the lower side of the adsorption column through magnetic attraction and temporarily positions it under the upper electrode head, facilitating subsequent downward pushing into place before subsequent welding operations.

Description

Technical Field

[0001] This utility model relates to resistance welding technology, and in particular to a nut and bolt feeding and positioning mechanism. Background Technology

[0002] Resistance welding is a metal fastening process that typically welds two workpieces together by applying a large current and pressure. For example, welding a nut or bolt to a housing workpiece where the housing workpiece has a pre-machined hole concentric with the nut to be welded, or a hole through which the bolt passes to weld the flange bottom to the housing. Currently, robotic arms are commonly used to deliver the housing workpiece to the workstation. When the robotic arm is in place, it is usually positioned at a specific spatial point between the upper and lower electrodes. However, the horizontal position of the housing workpiece may differ from the axis of the upper and lower electrodes. Therefore, it is usually necessary to move the upper and lower electrodes and the workpiece to correct for minor dimensional errors, ensuring that the center of the hole on the housing workpiece coincides with the axis of the upper and lower electrodes.

[0003] Many existing bow clamps are installed on the welding machine base using a horizontal moving mounting method. After each welding operation, the bow clamp frame, along with the upper and lower electrode assemblies, remains in the position where the previous welding was completed. However, after multiple welding operations, the position may deviate significantly, potentially causing the positions of consecutive welding operations to exceed the adjustment range of the alignment mechanism. To maintain a relatively definite original position for the bow clamp frame and electrode assemblies, a return mechanism is needed to return them to their original positions. Before the next welding operation, the bow clamp frame is released when the workpiece arrives, aligning the electrodes with the workpiece. This method requires a planar push-pull motion between welding operations to return the bow clamp to its initial position, causing a time delay in the welding cycle and affecting welding efficiency. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the technical problem to be solved by this utility model is to provide a nut and bolt feeding and positioning mechanism that can deliver materials and workpieces to the workstation and accurately position and place them in the welding processing position to eliminate positioning errors, even when there are certain dimensional errors.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a nut and bolt feeding and positioning mechanism, which includes an upper electrode assembly that can be floated and installed on the machine base, and a feeding gun that can extend to feed to the lower side of the upper electrode assembly. The upper electrode assembly includes a cylindrical upper electrode head, an adsorption column disposed in the upper electrode head, and a magnetic suction body disposed in the adsorption column. The feeding gun includes a gun frame, a feeding rod that can be telescopically installed on the gun frame, and a feeding hand connected to the feeding rod and that can be pushed to the lower side of the upper electrode head.

[0006] As an improvement to the technical solution of the nut and bolt feeding and positioning mechanism of this utility model, the upper electrode assembly includes a hollow tubular upper electrode rod with its lower end fixedly connected to the upper electrode head, and an auxiliary cylinder fixedly installed on the upper electrode rod and capable of driving the adsorption column and the magnetic accelerator to move axially. The output rod of the auxiliary cylinder extends axially through the hollow tube cavity of the upper electrode rod and is fixedly connected to the adsorption column.

[0007] As an improvement to the technical solution of the nut and bolt feeding and positioning mechanism of this utility model, the upper electrode rod is equipped with a side cylinder parallel to the axis of the upper electrode rod. A push-pull sleeve driven by the side cylinder and slidably sleeved on the upper electrode rod has three circumferentially distributed grippers elastically retracted at the lower end of the push-pull sleeve. The outer periphery of the upper electrode head is provided with a side sliding groove that extends axially and is adapted to the grippers. The bottom circumferential diameter of the side sliding groove is consistent with the radial dimension of the flange of the clamped bolt.

[0008] As an improvement to the technical solution of the nut and bolt feeding and positioning mechanism of this utility model, the lower end of the adsorption column is blunt conical and can extend out of the upper electrode head.

[0009] As an improvement to the technical solution of the nut and bolt feeding and positioning mechanism of this utility model, the upper electrode assembly further includes a main electric cylinder vertically installed at the upper end of the upper electrode rod, and the lower output end of the main electric cylinder is provided with a side clamp for clamping the upper electrode rod from the side.

[0010] As an improvement to the technical solution of the nut and bolt feeding and positioning mechanism of this utility model, the gun frame is fixedly installed with a feeding cylinder, the output end of the feeding cylinder is fixedly connected to the feeding rod, and the rear end of the feeding hand is hinged to the front end of the feeding rod so that it can be pulled out and flipped up.

[0011] As an improvement to the technical solution of the nut and bolt feeding and positioning mechanism of this utility model, the feeding hand has a material loading groove formed by a central depression.

[0012] As an improvement to the technical solution of the nut and bolt feeding and positioning mechanism of this utility model, the feeding rod is fitted with a traveling sleeve that can move axially with the feeding rod, and the gun frame is provided with a misalignment mechanism that can drive the traveling sleeve to be axially misaligned with the feeding rod. The lower rear end of the feeding hand is hinged to the front end of the feeding rod, and the upper rear end of the feeding hand is hinged to the front end of the traveling sleeve. When the traveling sleeve is axially misaligned with the feeding rod, the feeding rod pushes forward and the traveling sleeve pulls backward, causing the front end of the feeding hand to swing upward and tilt.

[0013] As an improvement to the technical solution of the nut and bolt feeding and positioning mechanism of this utility model, the lower side of the accompanying sleeve is cut off to form a clearance position, and the misalignment mechanism includes a limiting block provided on the gun frame and partially extending into the clearance position, and a pull buckle that completes the rear end of the accompanying sleeve to terminate the formation of the clearance position.

[0014] As an improvement to the technical solution of the nut and bolt feeding and positioning mechanism of this utility model, the upper side of the feeding gun is provided with a feeding cylinder, and the gun frame includes a sleeve through which the feeding rod and the accompanying sleeve pass. When the feeding rod is retracted, the feeding hand is located in front of the sleeve, and the feeding hand is located at the outlet of the feeding cylinder.

[0015] The beneficial effects of this utility model are as follows: The nut and bolt feeding and positioning mechanism includes a magnetic suction column that extends from the inner hole of the upper electrode head or stops inside the upper electrode head, flush with its lower end face, when a bolt / nut workpiece needs to be attracted. The feeding rod delivers the feeder carrying the bolt / nut workpiece to the lower side of the upper electrode head. The magnetic suction attracts the workpiece to the lower side of the suction column, temporarily fixing its position below the upper electrode head for easy downward pushing into place before subsequent welding. Even with certain dimensional errors, the upper electrode head and feeder in this mechanism can deliver the workpiece to the upper electrode head position and accurately position it for welding using magnetic attraction. Adjusting the workpiece's position through magnetic attraction eliminates positioning errors and achieves precise feeding. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of a floating welding machine welding system according to the present invention.

[0017] Figure 2 for Figure 1 The diagram shows a side view of the main unit of the floating welding machine system.

[0018] Figure 3 for Figure 2 The diagram shows the structure of the main unit of the floating welding machine system with the single-sided column removed.

[0019] Figure 4 for Figure 1 The diagram shows a three-dimensional structural schematic of the upper electrode assembly of the clamping bolt in the floating welding machine welding system.

[0020] Figure 5 for Figure 4 The diagram shows a lateral longitudinal section of the upper electrode assembly.

[0021] Figure 6 for Figure 1 The diagram shows a three-dimensional structural schematic of the upper electrode assembly for clamping the nut in the floating welding machine welding system.

[0022] Figure 7 for Figure 6 The diagram shows a lateral longitudinal section of the upper electrode assembly.

[0023] Figure 8 for Figure 1 The diagram shows a three-dimensional structure of the feed gun in the floating welding machine system.

[0024] Figure 9 for Figure 8 The diagram shows a lateral longitudinal section of the feed gun in its retracted state.

[0025] Figure 10 for Figure 8 The diagram shows a lateral longitudinal section of the feed gun with the feed rod extended.

[0026] Figure 11 for Figure 8 The diagram shows a lateral longitudinal section of the feed gun with the feed rod extended to its position and the feed handle raised.

[0027] Figure 12 for Figure 8 The diagram shows a three-dimensional structure of the feed gun in a semi-section state. Detailed Implementation

[0028] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings.

[0029] like Figure 1 , Figure 2 , Figure 3 , Figure 5 , Figure 6As shown, this utility model discloses a nut and bolt feeding and positioning mechanism, which includes an upper electrode assembly 51 that can be floated and installed on a machine base 31, and a feeding gun 81 that can extend to feed material to the lower side of the upper electrode assembly 51. The upper electrode assembly 51 includes a cylindrical upper electrode head 53a / 53b, an adsorption column 54 disposed in the upper electrode head 53a / 53b, and a magnetic suction body 55 disposed in the adsorption column. The feeding gun 81 includes a gun frame 82, a feeding rod 84 that can be telescopically installed on the gun frame, and a feeding hand 86 that is connected to the feeding rod 84 and can be pushed to the lower side of the upper electrode head 53a / 53b. When the magnetic suction column 54, equipped with a magnetic suction body 55, needs to suction the bolt workpiece 29 / nut workpiece 28, it extends from the inner hole of the upper electrode head 53a / 53b or stops inside the upper electrode head, flush with its lower end face. The feeding rod 84 delivers the feeding hand 86 carrying the bolt workpiece 29 / nut workpiece 28 to the lower side of the upper electrode head 53a / 53b. The magnetic suction body 55 attracts the workpiece to the lower side of the suction column 54 through magnetic attraction, and temporarily positions it under the upper electrode head 53a / 53b, facilitating subsequent downward pushing into place before proceeding with the welding operation. In the nut and bolt feeding and positioning mechanism, the upper electrode head 53a / 53b and the feeding hand 86 can deliver the material workpiece to the upper electrode head station even with certain dimensional errors. Through magnetic attraction, the workpiece is accurately positioned and placed in the welding processing position of the upper electrode head 53a / 53b. The magnetic attraction adjusts the position of the workpiece, thereby eliminating positioning errors and achieving precise feeding.

[0030] Among them, such as Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown, the upper electrode assembly 51 includes a hollow tubular upper electrode rod 52 with its lower end fixedly connected to the upper electrode heads 53a / 53b, and a secondary cylinder 56 fixedly installed on the upper electrode rod 52 and capable of driving the adsorption column 54 and the magnetic accumulator 55 to move axially. The output rod of the secondary cylinder 56 extends axially through the hollow tube of the upper electrode rod 52 and is fixedly connected to the adsorption column 54. Thus, under the driving action of the secondary cylinder 56, the adsorption column 54 equipped with the magnetic accumulator 55 can extend and retract axially. When it is necessary to adsorb the bolt workpiece 29 / nut workpiece 28, it extends out from the inner hole of the upper electrode head 53a / 53b or stops inside the upper electrode head 53a / 53b and is flush with its lower end face. During welding, the adsorption column 54 and the magnetic accumulator 55 are pulled upward and retracted away from the vicinity of the high-temperature welding area, which has a good protective effect on maintaining the magnetism of the magnetic accumulator 55 and avoids demagnetization due to heat.

[0031] Furthermore, such as Figure 4 , Figure 5As shown, the upper electrode rod 52 is fixedly connected to a side seat 61, and the side seat 61 is fixedly mounted with a side cylinder 62 parallel to the axis of the upper electrode rod 52. A push-pull sleeve 63 driven by the side cylinder 62 and slidably sleeved on the upper electrode rod 52 is elastically retracted and mounted on the lower end of the push-pull sleeve 63 with three circumferentially distributed grippers 64. The outer periphery of the upper electrode head 53a is provided with a side sliding groove 57 that extends axially and is adapted to the grippers 64. The bottom circumferential diameter of the side sliding groove 57 is consistent with the radial dimension of the flange of the clamped bolt 29. The driving action of the side cylinder 62 allows the push-pull sleeve 63 and the gripper 64 to move axially. The gripper 64 moves vertically in the side slide groove 57, thereby adjusting the extent to which it extends beyond the lower end of the upper electrode head 53a. This adapts to nuts / bolt flanges of different thicknesses, providing a more stable grip. When the upper electrode head 53a wears, the extension of the gripper 64 can be reduced to prevent excessive downward extension and contact with another workpiece being welded. The gripper 64 is mounted to the lower end of the push-pull sleeve 64 via a spring pin 65, allowing it to be used with nuts / bolt flanges of different sizes and thicknesses. The internal size of the gripper when tightened depends on the bottom annular diameter of the multiple side slide grooves 57. The cylinder-driven push-pull sleeve 63 and gripper 64 allow the gripper 64 to have a certain degree of backward cushioning, enabling it to retract under pressure when its lower end contacts other workpieces. When not in use, the gripper can be retracted upwards.

[0032] Among them, such as Figure 7 , Figure 8 As shown, the lower end of the adsorption column 54b is bluntly conical and extends beyond the upper electrode head 53b. It is used to pick up the nut 28, and under the drive of the auxiliary cylinder 56, the conical head at the lower end of the adsorption column 54b is pushed downwards into the inner hole of the nut 28, correcting the nut's position and centering it. With the nut 28 centered, the welding hole position of the workpiece is also correspondingly centered, allowing the nut 28 to be welded to the corresponding hole position. The magnetic attractor 55 in the adsorption column 54b is located above the lower conical head, attracting the nut 28 upwards to the upper electrode head 53b for easy welding.

[0033] Furthermore, such as Figure 1 , Figure 2 , Figure 3 , Figure 5As shown, the upper electrode assembly 51 also includes a main electric cylinder 66 vertically mounted at the upper end of the upper electrode rod 52. The main electric cylinder drives the upper electrode rod 52 to move axially up and down and is responsible for applying welding pressure. Typically, the upper end of the main electric cylinder 66 is connected to a drive motor 68 to generate rotational power, which is then converted into axial driving force by the main electric cylinder 66. The lower output end of the main electric cylinder 66 is provided with a side clamp 67 for clamping the upper electrode rod 52 from the side, so that the upper electrode rod 52 is parallel to the output shaft of the main electric cylinder 66 and is fixedly connected together by the side clamp 67. Thus, there is space above the upper electrode rod 52 for installing the auxiliary cylinder 56. The output shaft 56a of the auxiliary cylinder is provided with an inner transmission rod 69 inside the upper electrode rod 52, so that the bottom end of the inner transmission rod 69 can be connected to and drive the adsorption columns 54a / 54b to move axially up and down, extending downward to adsorb the nut / bolt. During high-temperature welding, the workpiece is clamped by the upper and lower electrode heads. At this time, the adsorption columns 54a / 54b and the magnetic accumulator 55 retract to avoid the high temperature affecting the magnetism of the magnetic accumulator 55.

[0034] The feeding gun can be configured separately, independent of the main unit. Its feeding position can be adjusted at the installation site to meet requirements. Figure 8 , Figure 9 , Figure 12 As shown, a feeding cylinder 83 is fixedly mounted on the rear end of the gun holder 82. The output shaft of the feeding cylinder 83 is fixedly connected to the feeding rod 84. The rear end of the feeding hand 86 is hinged to the front end of the feeding rod 84, so that the feeding hand 86 can be pulled and flipped up. Under the driving action of the feeding cylinder 83, the feeding rod 84 can be extended / retracted. When the feeding rod 84 extends, the feeding hand 86 moves the workpiece to the lower side of the upper electrode head 53a / 53b. The feeding hand 86 is then pulled and flipped up, lifting the workpiece to a certain height so that it can be picked up and moved to the upper electrode head for removal. Under the action of the feeding cylinder, the feeding rod 84 retracts, causing the feeding hand 86 to return to the position of receiving the next workpiece, waiting for the next round of processing.

[0035] Furthermore, the feeder 86 has a material loading groove formed by a central depression to accommodate the corresponding workpiece.

[0036] Specifically, the feed rod 84 is fitted with a traveling sleeve 85 that can move axially with the feed rod 84. The gun holder is provided with a misalignment mechanism that can drive the traveling sleeve 85 to be axially misaligned with the feed rod 84. The lower rear end of the feed hand 86 is hinged to the front end of the feed rod 84, and the upper rear end of the feed hand 86 is hinged to the front end of the traveling sleeve 85. When the traveling sleeve 85 is axially misaligned with the feed rod 84, the feed rod 84 pushes forward and the traveling sleeve 85 pulls back, causing the front end of the feed hand 86 to swing upward. The traveling sleeve 85 is driven by the feed cylinder 83 along with the feed rod 84, so that after the feed hand 86 at the front end receives the workpiece bolt or nut, it moves forward to the lower side of the upper electrode head 53a / 53b, such as... Figure 10 As shown; when it reaches the lower side of the upper electrode head 53a / 53b, the misalignment mechanism drives the traveling sleeve 85 and the feeding rod 84 to axially misalign. The traveling sleeve 85 stops moving forward while the feeding rod 84 continues to move forward axially, causing the feeding hand 86 to swing upward and tilt up, as shown. Figure 11 As shown, this causes the workpiece bolt or nut to be fed upwards towards the upper electrode head 53a / 53b. When it approaches the upper electrode head 53a / 53b, the workpiece bolt or nut is attracted and moved upwards, thus detaching from the feeder 86, completing the workpiece transfer. Subsequently, the feed cylinder 83 drives the feed rod 84 to retract, causing the feed rod 84 to drive the feeder 86 to swing down and reset, and then, together with the accompanying sleeve 85, pull backwards to return to the original position.

[0037] like Figure 8 , Figure 10 As shown, the misalignment mechanism includes a double hinge 87. One end of the double hinge 87 is hinged to the feeder 86, and the other end of the double hinge 87 is hinged to the front end of the traveling sleeve 85. Together with the feed rod 84, they form a linkage mechanism, which allows the misalignment caused by the swing of the feeder 86 to be absorbed by the double hinge 87, thus preventing the swing and rotation of the feeder 86 from being restricted.

[0038] Furthermore, such as Figure 9 , Figure 12 As shown, the lower side of the traveling sleeve 85 is cut off to form a clearance position 88. The misalignment mechanism includes a limiting block 91 located on the gun holder 82 and partially extending into the clearance position 88, and a pull buckle 89 that completely terminates the formation of the clearance position at the rear end of the traveling sleeve. During the feeding process, the limiting block 91 does not obstruct the forward and backward movement of the traveling sleeve 85 at the clearance position 88; however, before the feeding arrives, the limiting block 91 blocks the pull buckle 89 on the rear side of the clearance position 88, causing the traveling sleeve 85 to stop axially moving forward, while the feeding rod 84 continues to move forward, thus generating axial misalignment, which drives the feeding hand 86 to swing and push the workpiece upward.

[0039] When reversing, after the limit stop 91 is released from blocking the pull buckle, the traveling sleeve 85 and the feeding rod 84 can be misaligned in the opposite direction under the action of the elastic reset component, eliminating the original misalignment size, and allowing the front end of the feeding hand 86 to swing down to facilitate the subsequent loading of new workpieces.

[0040] Furthermore, such as Figure 1 , Figures 8-12As shown, the upper side of the feeding gun 81 is provided with a feeding cylinder 93. The gun frame 82 includes a sleeve 96 through which the feeding rod 84 and the accompanying sleeve 85 pass. When the feeding rod 84 is retracted, the feeding hand 86 is located in front of the sleeve 96 and at the outlet of the feeding cylinder 93, facilitating the receiving of workpiece screws or nuts flowing out of the feeding cylinder 93. The sleeve 96 is used to fix and install the feeding cylinder 83 and allows the output shaft of the feeding cylinder 83, the feeding rod 84, and the accompanying sleeve 85 to move axially through and through it. The front end of the sleeve 96 is provided with a sliding sleeve to radially limit the accompanying sleeve 85, ensuring its radial dimensional accuracy, thereby providing a stable and accurate delivery position to the endpoint. The rear end of the feeding cylinder 93 is connected to a vibrating plate 95, which orients and sorts the workpieces and delivers them one by one to the feeding cylinder 93, forming the starting point of material conveying.

[0041] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the scope of the present utility model application shall still fall within the scope of the present utility model.

Claims

1. A nut and bolt feeding and positioning mechanism, characterized by: The device includes an upper electrode assembly that can be floated and mounted on a base, and a feeding gun that can extend to feed material to the lower side of the upper electrode assembly. The upper electrode assembly includes a cylindrical upper electrode head, an adsorption column disposed within the upper electrode head, and a magnetic suction body disposed within the adsorption column. The feeding gun includes a gun frame, a feeding rod that can be telescopically mounted on the gun frame, and a feeding hand connected to the feeding rod and that can be pushed to the lower side of the upper electrode head.

2. The nut and bolt feed positioning mechanism of claim 1, wherein: The upper electrode assembly includes a hollow tubular upper electrode rod with its lower end fixedly connected to the upper electrode head, and an auxiliary cylinder fixedly installed on the upper electrode rod and capable of driving the adsorption column and magnetic body to move axially. The output rod of the auxiliary cylinder extends axially through the hollow tube cavity of the upper electrode rod and is fixedly connected to the adsorption column.

3. The nut and bolt feed positioning mechanism of claim 2, wherein: The upper electrode rod is equipped with a side cylinder parallel to the axis of the upper electrode rod. A push-pull sleeve driven by the side cylinder and slidably sleeved on the upper electrode rod has three circumferentially distributed grippers installed elastically at the lower end of the push-pull sleeve. The outer periphery of the upper electrode head is provided with a side sliding groove that extends axially and is adapted to the grippers. The bottom circumferential diameter of the side sliding groove is consistent with the radial dimension of the flange of the clamped bolt.

4. The nut and bolt feed positioning mechanism of claim 2, wherein: The lower end of the adsorption column is blunt and conical and can extend out of the upper electrode head.

5. The nut and bolt feed and positioning mechanism of claim 3 or 4, wherein: The upper electrode assembly also includes a main electric cylinder vertically installed at the upper end of the upper electrode rod, and the lower output end of the main electric cylinder is provided with a side clamp for clamping the upper electrode rod from the side.

6. The nut and bolt feed positioning mechanism of claim 1, wherein: The gun holder is fixedly equipped with a feeding cylinder, the output shaft of which is fixedly connected to the feeding rod. The rear end of the feeding hand is hinged to the front end of the feeding rod, so that it can be pulled out and flipped up.

7. The nut and bolt feed positioning mechanism of claim 6, wherein: The feeding hand has a material loading groove formed by a central depression.

8. The nut and bolt feed positioning mechanism of claim 6, wherein: The feeding rod is fitted with a traveling sleeve that can move axially with the feeding rod. The gun frame is provided with a misalignment mechanism that can drive the traveling sleeve to be axially misaligned with the feeding rod. The lower rear end of the feeding hand is hinged to the front end of the feeding rod, and the upper rear end of the feeding hand is hinged to the front end of the traveling sleeve. When the traveling sleeve is axially misaligned with the feeding rod, the feeding rod pushes forward and the traveling sleeve pulls backward, causing the front end of the feeding hand to swing upward and tilt.

9. The nut and bolt feed positioning mechanism of claim 8, wherein: The lower side of the accompanying sleeve is cut off to form a clearance position. The misalignment mechanism includes a limiting block provided on the gun mount and partially extending into the clearance position, and a pull buckle that completes the rear end of the accompanying sleeve to terminate the formation of the clearance position.

10. The nut and bolt feed positioning mechanism of claim 6, wherein: The upper side of the feeding gun is provided with a feeding cylinder, and the gun frame includes a sleeve through which the feeding rod and the accompanying sleeve pass. When the feeding rod is retracted, the feeding hand is located in front of the sleeve and at the outlet of the feeding cylinder.

Images