CN110078007B

CN110078007B - Automatic tightening device for external thread bottle cap

Info

Publication number: CN110078007B
Application number: CN201910351814.2A
Authority: CN
Inventors: 李大伟; 李也然; 耿铭; 徐轶轲; 申研
Original assignee: Beijing Machinery Equipment Research Institute
Current assignee: Beijing Machinery Equipment Research Institute
Priority date: 2019-04-28
Filing date: 2019-04-28
Publication date: 2021-04-20
Anticipated expiration: 2039-04-28
Also published as: CN110078007A

Abstract

The invention relates to an automatic screwing device for an external thread bottle cap, belongs to the technical field of packaging machinery, and solves the problems that the existing screwing device cannot meet the requirements of screwing a metal external thread bottle cap and a bottle internal thread with large mass, poor elastoplasticity, small thread pitch and many turns, and the automation degree is low. The automatic tightening device comprises a frame and a conveying device for conveying product bottles and bottle caps to a designated position; the frame is provided with a bottle body alignment clamping assembly and a bottle cap screwing assembly; the bottle body alignment clamping assembly comprises a centering clamping cylinder and a horizontal cylinder, wherein the centering clamping cylinder is used for clamping a product bottle body; the horizontal cylinder controls the horizontal movement of the centering clamping cylinder to position the centering clamping cylinder to a working position; the bottle cap screwing assembly comprises a screwing head, a servo unit for driving the screwing head to rotate and a vertical air cylinder for controlling the servo unit to move up and down. The automatic screwing device realizes the automatic screwing of the external thread bottle cap.

Description

Automatic tightening device for external thread bottle cap

Technical Field

The invention relates to the technical field of packaging machinery, in particular to an automatic screwing device for an external thread bottle cap.

Background

The existing mature bottle cap screwing equipment can realize automatic screwing between a plastic bottle cap and a plastic bottle body and between a metal bottle cap and a glass bottle body, and is characterized in that:

1) the bottle cap is small in mass and mainly made of plastic or metal materials with good elastic and plastic properties;

2) the threads of the bottle cap are mainly internal threads, and the threads of the bottle body are mainly external threads;

3) the pitch of the thread is typically 2 to 3mm, the number of turns is typically 2 to 3 turns;

the tightening torque required in such cases is usually small, and the tightening principle is mainly realized by contacting the tightening head with the upper surface of the bottle cap and driving the bottle cap to rotate by the friction force between the contact surfaces, so as to realize automatic tightening.

The existing automatic tightening device generally comprises a fastening piece (such as a screw, a nut and the like) and automatic tightening of a packaging bottle cap and a bottle body (such as a mineral water bottle, a glass can and the like), wherein the automatic tightening device of the packaging bottle cap and the bottle body is mostly suitable for tightening between a plastic bottle cap or a metal internal thread bottle cap with small quality, good elastic plasticity (small rigidity), large thread pitch and few turns and an external thread of the bottle body, the required tightening torque of the situation is usually small, the tightening principle of the automatic tightening device mainly contacts with the upper surface of the bottle cap through a tightening head, and the bottle cap is driven to rotate by the friction force between contact surfaces, so that the automatic tightening is realized. And to the circumstances that the quality is big, the elastoplasticity is poor (the rigidity is big), the screw pitch is little, the many metal external screw thread bottle lid of the number of turns and bottle internal thread cooperate, its required tightening torque is great usually, obviously lean on the form of frictional force between the contact surface can not provide required tightening torque for the external screw thread bottle lid that possesses above-mentioned characteristic to there is the automatic solution of screwing up freshly, consequently to the external screw thread product that has above characteristic, an automatic tightening device that needs to be designed to urgent need, in order to adapt to the automation of this kind of product and screw up.

Disclosure of Invention

In view of the above analysis, the present invention aims to provide an automated tightening device for external screw caps, which is used to solve the problem that the existing tightening device cannot satisfy the requirements of large mass, poor elasticity and plasticity, small screw pitch, large number of turns of tightening of metal external screw caps and internal screw threads of bottle bodies, and low automation degree.

The purpose of the invention is mainly realized by the following technical scheme:

an automatic tightening device for externally threaded bottle caps comprises a frame, a conveying device and a tightening device, wherein the conveying device is used for conveying product bottles and bottle caps to a specified position; the frame is provided with a bottle body alignment clamping assembly and a bottle cap screwing assembly; the bottle body alignment clamping assembly comprises a centering clamping cylinder and a horizontal cylinder, wherein the centering clamping cylinder is used for clamping a product bottle body; the horizontal cylinder controls the horizontal movement of the centering clamping cylinder to position the centering clamping cylinder to a working position; the bottle cap screwing assembly comprises a screwing head, a servo unit for driving the screwing head to rotate and a vertical air cylinder for controlling the servo unit to move up and down.

Further, the conveying device comprises a bottle body conveying assembly used for conveying the product bottles and a bottle cap conveying assembly used for grabbing and moving the bottle caps.

Furthermore, the tightening head comprises a mounting base body, a telescopic rod and a spring sleeved on the telescopic rod, the mounting base body is provided with a reducing through hole used for the telescopic rod to move up and down, and the longitudinal section of the reducing through hole is convex; one end of the telescopic rod is coaxially provided with a working part matched with the slotted hole at the top of the bottle cap, and the other end of the telescopic rod is provided with a limiting part used for limiting the telescopic rod to slide downwards; the working part comprises an end head and a working cylinder, the diameter of the end head is smaller than or equal to the aperture of the slotted hole, and the diameter of the working cylinder is larger than the aperture of the slotted hole and smaller than or equal to the aperture of the lower part of the reducing through hole.

Furthermore, the number of the telescopic rods is at least two, and the telescopic rods are provided with the reducing through holes and the springs in corresponding numbers.

Further, the limiting part comprises a limiting hole and a limiting pin; or the limiting part is an integrally formed barrier bulge.

Furthermore, the installation base member is the structure of falling U-shaped, and the reducing through-hole is located the structure both sides of falling U-shaped.

Further, the bottle cap conveying assembly comprises an air claw and air claw connecting plates arranged on two sides of the air claw, wherein roller structures are arranged at the end parts of the air claw connecting plates and are symmetrically arranged relative to the air claw; the roller structure comprises a roller support and a plurality of roller assemblies, the roller assemblies are arranged on the roller support in parallel, and the roller assemblies are used for clamping bottle caps and centering and positioning the bottle caps.

Furthermore, the roller assembly comprises a roller and a connecting rod, and the roller is fixedly connected to the end part of the connecting rod; the last symmetry of gyro wheel support sets up two support through-holes, and the length of connecting rod is greater than the thickness of gyro wheel support, and the connecting rod can just can reciprocate at support through-hole internal rotation.

Furthermore, the roller assembly comprises a roller, and the other end of the connecting rod is fixedly provided with a clamping part.

Further, the roller assembly comprises two rollers, and the two rollers are arranged at two ends of the connecting rod.

Compared with the prior art, the invention has at least one of the following beneficial effects:

a) the automatic tightening device for the external thread bottle cap is provided with the automatic bottle body conveying assembly, the automatic bottle cap conveying assembly, the automatic bottle body aligning and clamping assembly and the automatic bottle cap tightening assembly, the automation of the whole tightening process is realized, the automatic tightening device is simple in structure and high in working reliability, the production cost is obviously reduced, the adaptability to products is high, the adaptive tightening head, the automatic bottle body conveying assembly and the automatic bottle cap conveying assembly can be matched according to the models of the product bottle body and the product cap, the optimal tightening force adaptive to the product can be set according to the requirements of different products, the product consistency is good, the yield is high, and the automatic tightening requirements of novel products can be quickly adapted.

b) The automatic screwing device for the external thread bottle cap adopts the specially designed screwing head, and the plurality of telescopic rods capable of stretching are arranged on the mounting base body, and the working ends of the telescopic rods are matched with the slotted holes in the bottle cap, so that the automatic screwing of the metal external thread bottle cap with large mass, poor elastic-plastic property (large rigidity), small screw pitch and large number of turns is realized, the problem of small static friction moment of the traditional contact surface is solved, the screwing head is clamped into the slotted hole of the bottle cap to provide larger screwing torque, the optimal number of the telescopic rods can be configured according to the requirement of a product structure, the optimal stability in the screwing process is obtained, and the expansibility is strong.

c) According to the automatic screwing device for the external thread bottle cap, the bottle cap conveying assembly is provided with the roller structures symmetrically arranged on the two sides of the gas claw, so that centering positioning and additional Z-axis rotation freedom degrees can be realized, the circular bottle cap type workpiece can be accurately grabbed, the circular bottle cap type workpiece can be rotated by matching with other equipment, and the application prospect is wide.

In the invention, the technical schemes can be combined with each other to realize more preferable combination schemes. Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The drawings are only for purposes of illustrating particular embodiments and are not to be construed as limiting the invention, wherein like reference numerals are used to designate like parts throughout.

Fig. 1 is a first structural schematic diagram of an automatic tightening device for an externally threaded bottle cap according to an embodiment of the present invention;

fig. 2 is a second structural schematic diagram of an automated tightening device for an externally threaded bottle cap according to an embodiment of the present invention;

fig. 3 is a schematic view showing the lateral movement of the feeding process of the bottle cap conveying assembly of the automatic tightening device for the externally threaded bottle caps in the embodiment of the present invention;

fig. 4 is a schematic view showing the longitudinal movement of the feeding process of the bottle cap conveying assembly of the automatic tightening device for the externally threaded bottle caps in the embodiment of the present invention;

fig. 5 is a schematic structural view of a tightening head of the automated tightening device for externally threaded bottle caps in the embodiment of the present invention;

fig. 6 is a disassembled schematic view of the structure of the tightening head of the automatic tightening device for the externally threaded bottle cap according to the embodiment of the present invention;

fig. 7 is a schematic structural view of a bottle cap conveying assembly of an automated tightening apparatus for externally threaded bottle caps in an embodiment of the present invention.

Reference numerals:

1-a frame; 2, carrying out tray tooling; 3-product bottle body; 4-centering the clamping cylinder; 5-screwing the head; 51-a telescopic rod; 52-a limit pin; 53-mounting a substrate; 54-a spring; 6-a servo unit; 7-a vertical cylinder; 8-horizontal cylinder; 9-bottle cap; 10-a bottle cap transport assembly; 101. a pneumatic claw; 102. a pneumatic claw connecting plate; 103. a roller bracket; 104. a roller; 105. a roller connecting piece; 106. a connecting rod; 107. a clamping part; 108. a roller assembly; 109. a roller structure; 1010. a telescopic link; 11-direction of movement of the cap transport assembly.

Detailed Description

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate preferred embodiments of the invention and together with the description, serve to explain the principles of the invention and not to limit the scope of the invention.

In one embodiment of the present invention, an automated tightening apparatus for externally threaded bottle caps is disclosed, as shown in fig. 1 to 4, which includes a frame 1, a conveying apparatus for conveying product bottles 3 and bottle caps 9 to designated positions, the conveying apparatus including a bottle conveying assembly for conveying the product bottles 3 and a bottle cap conveying assembly 10 for grasping and moving the bottle caps 9; the frame 1 is provided with a bottle body alignment clamping assembly and a bottle cap 9 screwing assembly; the bottle body alignment clamping assembly comprises a centering clamping cylinder 4 and a horizontal cylinder 8, the moving parts of the centering clamping cylinder 4 and the horizontal cylinder 8 are connected through a mounting plate, and the centering clamping cylinder 4 is used for clamping the product bottle body 3; the horizontal cylinder 8 controls the horizontal movement of the centering clamping cylinder 4 to position the centering clamping cylinder 4 to a working position; the bottle cap 9 screwing assembly comprises a screwing head 5, a servo unit 6 and a vertical cylinder 7, wherein the servo unit 6 is used for driving the screwing head 5 to rotate, the vertical cylinder 7 is used for controlling the servo unit 6 to move up and down, the screwing head 5 is connected with a moving part of the servo unit 6 through a coupler, and the servo unit 6 is connected with a moving part of the vertical cylinder 7 through a mounting plate.

In this embodiment, the centering clamping cylinders 4 are disposed on the frame 1, the number of the centering clamping cylinders 4 is at least one, the centering clamping cylinders 4 are integrally connected with the moving part of the horizontal cylinder 8 through a mounting plate, and the centering clamping cylinders 4 are provided with left and right symmetrical moving parts. When the centering clamping cylinder 4 clamps, the symmetrical left and right moving parts move inwards at the same time, so that the bottle body of the product is clamped; when the centering clamping cylinder 4 is loosened, the moving parts which are symmetrical left and right move outwards at the same time, so that the bottle body of the product is loosened. In addition, in this embodiment, the automatic tightening device can be provided with the corresponding tightening head 5, bottle conveying assembly and bottle cap conveying assembly 10 according to the models of the product bottles 3 and the bottle caps 9, and can quickly meet the automatic tightening requirement of a novel product.

Aiming at the condition that a metal external thread bottle cap with large mass, poor elastic-plastic property (large rigidity), small thread pitch and multiple turns is matched with the internal thread of a bottle body, in order to provide enough large screwing torque in the process of screwing the bottle cap 9 so as to adapt to automatic screwing of a product with the external thread, the invention specially designs a screwing head 5, as shown in fig. 5 to 6, the screwing head comprises an installation base body 53, an expansion link 51 and a spring 54 sleeved on the expansion link 51, wherein the installation base body 53 is provided with a reducing through hole for the up-and-down movement of the expansion link 51, and the longitudinal section of the reducing through hole is convex; one end of the telescopic rod 51 is coaxially provided with a working part matched with the slotted hole at the top of the bottle cap 9, and the other end is provided with a limiting part used for limiting the downward sliding of the telescopic rod 51; the working part comprises an end head and a working cylinder, the diameter of the end head is smaller than or equal to the aperture of the slotted hole, and the diameter of the working cylinder is larger than the aperture of the slotted hole and smaller than or equal to the aperture of the lower part of the reducing through hole. The mounting base 53 is provided with a connecting portion to be connected to the servo unit 6.

In this embodiment, the number of the diameter-variable through holes is at least one, and the telescopic rods 51 and the springs 54 are provided in corresponding numbers. Preferably, the number of the reducing through holes is even, and the reducing through holes are uniformly and symmetrically arranged on the mounting base 53. When the number of the telescopic rods 51 is one, the slotted hole of the bottle cap 9 is a cross-shaped groove, the end of the telescopic rod 51 is of a cross-shaped structure, and the cross-shaped groove is matched with the cross-shaped structure to screw the bottle cap 9. When the number of the telescopic rods 51 is multiple, the number of the telescopic rods 51 corresponds to the number of the slotted holes formed in the bottle cap 9, the slotted holes can be smooth arc-shaped grooves or cross grooves, correspondingly, the smooth arc-shaped grooves correspond to the ends of the arc-shaped structures, and the cross grooves correspond to the ends of the cross structures. The tightening head 5 with the structure realizes the tightening of the round bottle cap 9, solves the problem of small static friction moment of the traditional contact surface, is clamped into the groove hole of the bottle cap 9 through the tightening head 5 to provide larger tightening torque, and can be widely applied to automatic tightening equipment of products of the type. When the tightening device is used, the optimal number of the telescopic rods 51 is configured according to the requirement of the product structure, namely the number of the slotted holes arranged on the bottle cap 9, so that the optimal stability in the tightening process is obtained, and the expansibility is strong.

In order to prevent the end of the telescopic rod 51 from scratching the upper surface of the bottle cap 9, when the end is of an arc structure, preferably, the top end of the end is of a spherical structure; when the end is in a cross structure, the surface of the cross structure is smooth. The lower end face of the mounting base body 53 is smoothly arranged, and the lower end face of the mounting base body 53 has higher flatness, so that the upper surface of the bottle cap 9 is effectively prevented from being scratched. Preferably, the contact portion of the tightening head with the bottle cap 1 is provided with a coating of polyurethane material, and the tightening head provided with the coating of polyurethane material can effectively prevent the surface of the bottle cap 1 from being scratched.

In this embodiment, the diameter-variable through hole includes a top hole and a bottom hole, the side surface of the working cylinder of the telescopic rod 51 is in clearance fit with the bottom hole of the mounting base 53, and the telescopic rod 51 extends out from the other side of the mounting base 53. One side of the telescopic rod 51 extending out of the mounting base 53 is provided with a limiting part for limiting the telescopic rod 51 to slide downwards, preferably, the limiting part comprises a limiting hole and a limiting pin 52, and the limiting pin 52 is in interference fit with a pin hole at the non-working end of the telescopic rod 51; or, the limiting part is an integrally formed barrier protrusion, and the barrier protrusion can limit the telescopic rod 51 to completely slide downwards.

In this embodiment, the telescopic rod 51 is disposed in the reducing hole, the spring 54 is sleeved on the telescopic rod 51, the purpose of the spring 54 is to move the bottle cap 9 to the position to be screwed, the vertical cylinder 7 vertically feeds the bottle cap downwards by the height L, when the end of the telescopic rod 51 extends into the slotted hole on the bottle cap 9, the vertical cylinder 7 further vertically feeds the height L downwards, so that the lower surface of the mounting base 53 is in contact with the upper surface of the cap 9, the spring 54 is in a compressed state, the elastic force of the spring 54 returning to its original state acts on the working cylinder, further, a certain pressure is applied to the bottle cap 9, so that the working cylinder arranged on the working part of the telescopic rod 51 is in contact with the upper surface of the bottle cap 9 in the working process of the tightening head 5, the working part of the telescopic rod 51 is tightly matched with the bottle cap 9, the dislocation is prevented, the bottle cap 9 is more stable, and the working stability of the tightening head 5 is greatly improved. Meanwhile, after the screwing is completed, the servo unit 6 stops rotating and vertically moves upwards to the initial position under the driving of the vertical oil cylinder, and the working part of the telescopic rod 51 is ejected to the bottom hole of the reducing hole due to the restoring force of the spring 54, namely, the end of the telescopic rod 51 is ejected out smoothly and automatically due to the existence of the spring 54, so that the telescopic rod is not required to be pulled out manually, the working efficiency is improved, and the automation degree is improved.

Considering that the spring 54 needs to provide elastic force during the tightening process of the bottle cap 9, the length of the spring 54 needs to meet certain conditions, the length of the spring 54 only needs to ensure that after the working part of the telescopic rod 51 is fully inserted into the bottom hole, the spring 54 can apply certain elastic force to the working part, preferably, the free length of the spring 54 is greater than or equal to the distance from the reducing part of the reducing through hole to the top end surface of the working cylinder, that is, when the flexible tightening head 5 is installed and the tightening head 5 is in a vertical state, the spring 54 is in a natural or compressed state, and a part of the working part is located in the bottom hole of the reducing through hole.

In order to make the rotation of the tightening head 5 more flexible, the mounting base 53 is configured as a hollow structure, preferably, the mounting base 53 is configured as an inverted U-shaped structure, and the reducing through holes are formed in two sides of the inverted U-shaped structure, so that the material usage is reduced, the weight of the mounting base 53 is reduced, and the movement flexibility of the tightening head 5 is improved.

In this embodiment, the movement carrier of the bottle cap conveying assembly 10 is not limited, and may adopt a two-axis, three-axis, six-axis mechanical arm and other grabbing movement forms, for this reason, the invention specially designs a bottle cap conveying assembly 10, as shown in fig. 7 (the mechanical arm is not shown in the figure), the bottle cap conveying assembly 10 includes an air claw 101 and air claw connecting plates 102 arranged at two sides of the air claw 101, the end portions of the air claw connecting plates 102 are provided with roller structures 109, and the roller structures 109 are symmetrically arranged relative to the air claw 101; the roller structure 109 comprises a roller bracket 103 and two roller assemblies 108, the two roller assemblies 108 are arranged on the roller bracket 103 in parallel, and the roller assemblies 108 are used for clamping the circular bottle cap 9 and centering and positioning the circular bottle cap 9. The roller assembly 108 comprises a roller 104 and a connecting rod 106, wherein the roller 104 is fixedly connected to the end of the connecting rod 106; two support through holes are symmetrically arranged on the roller support 103, the rod diameter of the connecting rod 106 is smaller than the aperture of the support through holes, the middle section of the connecting rod 106 is an optical axis, and the smooth through holes of the roller support 103 are connected in a clearance fit manner. The length of connecting rod 106 is greater than the thickness of gyro wheel support 103, and connecting rod 106 can just can reciprocate certain distance in the rotation of support through-hole.

In this embodiment, at least two roller assemblies 108 are disposed on each roller structure 109, and preferably, two roller assemblies 108 are disposed in parallel on each roller structure 109. Each roller assembly 108 is provided with at least one roller 104, and the roller structures 109 provided on the roller brackets 103 are identical. Preferably, each roller assembly 108 comprises a roller 104, the roller 104 is disposed at one end of the connecting rod 106, the other end of the connecting rod 106 is fixedly provided with a clamping portion 107, the clamping portion 107 is used for limiting the connecting rod 106 in a bracket through hole of the roller bracket 103, the dimension of the clamping portion 107 is larger than the aperture of the through hole of the roller bracket 103, and the clamping portion 107 can be a nut or can be integrally formed with the connecting rod 106; each roller assembly 108 may also include two rollers 104, with two rollers 104 disposed at either end of the connecting rod 106. Of course, three or more rollers 104 may be provided on each roller assembly 108, and the roller assemblies 108 provided with a plurality of rollers 104 can realize centering positioning when the circular bottle caps 9 are gripped.

In order to facilitate the mounting and dismounting of the roller assembly 108, the connecting rod 106 is a screw rod with two ends provided with threads and a smooth middle part, the clamping part 107 is a nut, the roller 104 is in threaded connection with the connecting rod 106, the roller assembly 108 with the structure is convenient to assemble, and meanwhile, the damaged clamping part 107 or roller 104 can be replaced in time, so that the maintenance cost is reduced. In addition, the roller assembly 108 with the structure can select and replace the rollers 104 with different diameters according to the size of the round bottle cap 9 to be clamped, so that the universality of the bottle cap conveying assembly 10 is improved.

In this embodiment, the roller 104 center sets up the internal thread with connecting rod 106 screw thread assorted, the size of roller 104 is selected according to actual need, the support should be stretched out to the roller 104 periphery, the roller 104 diameter is greater than the width of roller connecting piece 105 and roller support 103 promptly, when guaranteeing to wait to press from both sides the contact of getting circular bottle lid 9 and roller 104 periphery, can avoid producing between the circular bottle lid 9 of pressing from both sides in the course of the work and the roller connecting piece 105 or the roller support 103 and interfere, the operational reliability of bottle lid transport assembly 10 has been promoted.

In order to improve the accuracy of centering and positioning, a roller connecting piece 105 is arranged between the roller 104 and the roller bracket 103, the roller connecting piece 105 is provided with a through hole for the connecting rod 106 to pass through, namely a connecting piece through hole, the connecting rod 106 penetrates through the bracket through hole and the connecting piece through hole, the roller connecting piece 105 can enable the connecting rod 106 in the working process to be in the same plane, the roller 104 is ensured to move in the same plane, and the clamping precision and the stability reduction caused by the fact that the connecting rod 106 is inclined are effectively prevented.

In order to improve the clamping stability of the bottle cap conveying assembly 10, the roller support 103 is fixedly arranged on the inner side of the gas claw connecting plate 102, two roller structures 109 connected to the roller support 103 are the same and are arranged oppositely, the rollers 104 of the roller assemblies 108 and the round bottle caps 9 to be clamped have at least four contact points, the bottle cap conveying assembly 10 with the structure is large in clamping force degree and more stable in clamping effect, centering positioning during clamping of the round bottle caps 9 can be automatically carried out, and the clamping is more accurate.

In order to improve the universality of the bottle cap conveying assembly 10, the gas claw connecting plate 102 is fixedly arranged on two sides of the gas claw 101 through threads, the roller bracket 103 is detachably connected with the gas claw connecting plate 102, the gas claw connecting plate 102 can be set to be different in size and structure, rollers 104 of different models can be replaced, and the detachable connecting structure can be suitable for clamping round bottle caps 9 of different models and can obviously improve the universality of the bottle cap conveying assembly 10, and meanwhile, the production cost and the maintenance cost are reduced.

In order to further improve the universality of the bottle cap conveying assembly 10, at least two rows of through holes of the roller supports 103 are arranged on the roller supports 103 in parallel, preferably two rows of through holes of the supports are arranged, namely four through holes of the roller supports 103 are arranged on each roller support 103, the centers of the through holes of the four roller supports 103 are connected to form a rectangle, the two roller assemblies 108 can be arranged at the diagonal positions of the rectangle, and can also be arranged on one side of the rectangle along the forward extending direction of the gas claw connecting plate 102, the roller supports 103 with the structure can clamp regular circular bottle caps 9 and non-circular bottle caps 9, such as polygonal workpieces like trapezoidal workpieces, rectangular workpieces and the like, and the application is wider. In addition, the roller bracket 103 can be further provided with a row of three or more roller bracket 103 through holes, or a plurality of rows of three or more roller bracket 103 through holes are arranged, the roller assemblies 108 can be arranged in the roller bracket 103 through holes at different positions according to the size and the shape of the workpiece to be clamped, so that the purpose of quickly clamping workpieces with different sizes and different shapes without disassembling and replacing the roller bracket 103 can be realized, and the device is convenient and quick.

In order to improve the gripping stability of the bottle cap conveying assembly 10, the surface of the roller 104 is provided with an anti-slip structure, and the anti-slip structure is anti-slip lines or anti-slip protrusions. In order to further improve the grabbing stability, the rollers 104 are made of polyurethane, and the surfaces of the rollers 104 made of polyurethane have certain anti-skid capacity, so that the grabbing stability of the bottle cap conveying assembly 10 is improved, the clamping is more stable, and meanwhile various anti-skid structures can be manufactured by polyurethane more easily.

In this embodiment, the mounting hole of the gas claw 101 of the bottle cap conveying assembly 10 is connected to the mechanical arm, the gas supply pipeline of the mechanical arm is connected to the gas claw input/output gas hole, the gas claw connecting plate 102 is connected to both sides of the gas claw 101 through the telescopic connecting rod 1010, the telescopic connecting rod 1010 is connected to the cylinder piston rod, and the telescopic connecting rod 1010 is driven by the cylinder to drive the gas claw connecting plate 102, so that clamping and loosening actions are realized. Before grabbing, the gas claw connecting plate 102 is in an open state, the gas claw connecting plate 102 in the open state is controlled by the front end of the mechanical arm to be folded inwards under the action of the gas claw 101, so that the circular bottle cap 9 to be clamped is clamped through the four roller assemblies 108, and the four roller assemblies 108 can realize centering and positioning of the circular bottle cap 9. Fig. 3 and 4 show the direction of movement 11 of the bottle cap transport assembly, the bottle cap transport assembly 10 having vertical and horizontal freedom of movement. After the bottle cap conveying assembly 10 moves the clamped round workpiece to the designated position, the mechanical arm continues to move downwards for a certain distance along the Z-axis, and the mechanical arm is in clearance fit with the unthreaded hole of the roller bracket 103 through the connecting rod 106, namely the roller assembly 108 can roll on the roller bracket 103 and move up and down, the roller assembly 108 is lifted to the highest point of the position relative to the roller bracket 103, and at the moment, the bottle cap 9 is driven to move downwards and rotate by matching with the vertical cylinder and the servo unit 6, so that the bottle cap 9 is screwed into the designated position. After the bottle cap 9 is screwed into the inner thread of the bottle body of the product, the gas claw 101 is opened outward, and is restored to an open state, and is moved back to an initial position by the mechanical arm.

The working process of the automated tightening device in this embodiment is as follows: under the non-working state, each part initial state of the automatic tightening device is as follows: the centering clamping cylinder 4 is opened, the horizontal cylinder 8 is retracted, the vertical cylinder 7 is retracted, the bottle cap conveying assembly 10 clamps one bottle cap 9 and stays outside the frame 1, and the servo unit 6 is stationary. When the automatic tightening device works, the product bottle bodies 3 are conveyed to the position right below the tightening device by the tray tool 2 through the bottle body conveying assembly, wherein the conveying mode of the bottle body conveying assembly is not limited, and preferably adopts conveying modes such as a double-speed chain, a conveying belt and the like; after the product bottle bodies 3 are conveyed to the position right below the tightening device, the horizontal cylinder 8 extends out to position the centering clamping cylinder 4 to a working position, the centering clamping cylinder 4 contracts to center and clamp the bottle bodies, and the bottle cap conveying assembly 10 carries the bottle caps 9 clamped by the bottle cap conveying assembly to move to corresponding positions right above the product bottle bodies 3; subsequently, the vertical cylinder 7 is extended to feed the servounit 6 and the tightening head 5 downwards, while the servounit 6, in the speed control mode, will start to reverse at a lower speed, the purpose of which is to insert the tightening head 5 into the slotted hole at the top of the cap 9; after the tightening head 5 is inserted into a slotted hole at the top of the bottle cap 9, the servo unit 6 starts to rotate forwards with a larger torque in a torque control mode to gradually screw the bottle cap 9 into the bottle body, in the process, the bottle cap conveying assembly 10 keeps a clamping state all the time and four pulleys on the bottle cap conveying assembly are displaced in the vertical direction along with the screwing of the bottle cap 9, after a certain time delay (the delay time is determined in the debugging process according to products with different sizes), the bottle cap conveying assembly 10 is opened and retreated to grab the next bottle cap 9 and finally stays outside the frame 1 to wait for the beginning of the next working cycle, and meanwhile, the servo unit 6 continues to screw the bottle cap 9 into the product bottle body 3 with the specified torque of product tightening in the torque control mode until the bottle cap is screwed; after screwing, the servo unit 6 is static, the vertical cylinder 7 contracts to lift the servo unit 6 and the screwing head 5 to the initial position, the centering clamping cylinder 4 loosens the bottle body, the horizontal cylinder 8 contracts to return the centering clamping cylinder 4 to the initial position, the product is conveyed out of the screwing device by the tray tool 2 through the bottle body conveying assembly, and the work flow is finished.

Compared with the prior art, the automatic tightening device for the external thread bottle cap provided by the embodiment is provided with an automatic bottle body conveying assembly, a bottle cap conveying assembly 10, a bottle body alignment clamping assembly and a bottle cap 9 tightening assembly, the automation of the whole tightening process is realized, the automatic tightening device is simple in structure, high in working reliability, the production cost is remarkably reduced, the adaptability to products is high, the adaptive tightening head 5, the bottle body conveying assembly and the bottle cap conveying assembly 10 can be matched according to the models of a product bottle body 3 and a bottle cap 9, the optimal tightening force adaptive to the automatic tightening device can be set according to the requirements of different products, the product consistency is good, the yield is high, and the automatic tightening requirement of a novel product can be quickly adapted. According to the specially designed tightening head 5, the telescopic rods 51 are arranged on the mounting base body 53, the working ends of the telescopic rods 51 are matched with the slotted holes in the bottle caps 9, automatic tightening of metal external thread bottle caps with large mass, poor elastoplasticity (high rigidity), small screw pitch and multiple turns is achieved, the problem that static friction force moment of a traditional contact surface is small is solved, the tightening head 5 is clamped into the slotted holes in the bottle caps 9 to provide larger tightening torque, the optimal number of the telescopic rods 51 can be configured according to the requirements of product structures, optimal stability in the tightening process is obtained, and expansibility is strong. In addition, the automatic screwing device adopts the specially designed bottle cap conveying assembly 10, the bottle cap conveying assembly 10 can realize centering positioning and additional Z-axis rotation freedom degree by symmetrically arranging the roller structures 109 on two sides of the air claw 101, so that the circular bottle workpieces can be accurately grabbed, and the circular bottle workpieces can realize rotation by matching with other equipment, and the application prospect is wide.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.

Claims

1. An automatic tightening device for external thread bottle caps is characterized by comprising a frame and a conveying device, wherein the conveying device is used for conveying product bottle bodies and bottle caps to a designated position; the frame is provided with a bottle body alignment clamping assembly and a bottle cap screwing assembly;

the bottle body alignment clamping assembly comprises a centering clamping cylinder and a horizontal cylinder, wherein the centering clamping cylinder is used for clamping the product bottle body; the horizontal cylinder controls the horizontal movement of the centering clamping cylinder to position the centering clamping cylinder to a working position;

the bottle cap screwing assembly comprises a screwing head, a servo unit for driving the screwing head to rotate and a vertical cylinder for controlling the servo unit to move up and down;

the tightening head comprises a mounting base body, a telescopic rod and a spring sleeved on the telescopic rod, the mounting base body is provided with a reducing through hole used for the telescopic rod to move up and down, and the longitudinal section of the reducing through hole is convex;

one end of the telescopic rod is coaxially provided with a working part matched with the slotted hole at the top of the bottle cap, and the other end of the telescopic rod is provided with a limiting part used for limiting the telescopic rod to slide downwards;

the working part comprises an end head and a working cylinder, the diameter of the end head is smaller than or equal to the aperture of the slotted hole, and the diameter of the working cylinder is larger than the aperture of the slotted hole and smaller than or equal to the aperture of the lower part of the reducing through hole;

the free length of the spring is more than or equal to the distance from the reducing position of the reducing through hole to the top end face of the working cylinder;

the mounting base body is of an inverted U-shaped structure, and the reducing through holes are formed in two sides of the inverted U-shaped structure.

2. The automated tightening apparatus for externally threaded bottle caps of claim 1, wherein the conveying means comprises a bottle body conveying assembly for conveying the product bottles and a cap conveying assembly for grasping and moving the caps.

3. The automated tightening device for the externally threaded bottle caps according to claim 1 or 2, wherein the number of the telescopic rods is at least two, and the telescopic rods are provided with a corresponding number of reducing through holes and springs.

4. The automated tightening device for externally threaded bottle caps according to claim 1 or 2, wherein the limiting part comprises a limiting hole and a limiting pin;

or the limiting part is a baffle boss which is integrally formed.

5. The automated tightening device for externally threaded bottle caps according to claim 1 or 2, wherein the bottle cap conveying assembly comprises a pneumatic claw and pneumatic claw connecting plates arranged on two sides of the pneumatic claw, wherein the end parts of the pneumatic claw connecting plates are provided with roller structures, and the roller structures are symmetrically arranged relative to the pneumatic claw;

the roller structure comprises a roller support and a plurality of roller assemblies, wherein the roller assemblies are arranged on the roller support in parallel and used for clamping the bottle cap and centering and positioning the bottle cap.

6. The automated tightening apparatus for externally threaded bottle caps according to claim 5, wherein the roller assembly comprises a roller and a connecting rod, the roller being fixedly connected to an end of the connecting rod;

the roller wheel support is symmetrically provided with two support through holes, the length of the connecting rod is larger than the thickness of the roller wheel support, and the connecting rod can rotate in the support through holes and can move up and down.

7. The automated tightening apparatus for the externally threaded bottle cap according to claim 6, wherein the roller assembly comprises a roller, and the other end of the connecting rod is fixedly provided with a locking portion.

8. The automated tightening apparatus for externally threaded bottle caps according to claim 6, wherein the roller assembly comprises two rollers, the two rollers being disposed at both ends of a connecting rod.