CN110802347A

CN110802347A - Welding back gas protection device

Info

Publication number: CN110802347A
Application number: CN201810885186.1A
Authority: CN
Inventors: 杨建明; 陈明春; 崔洪鹏; 邱军; 王建朗; 王建
Original assignee: China International Marine Containers Group Co Ltd; CIMC Enric Investment Holdings Shenzhen Co Ltd; Nantong CIMC Energy Equipment Co Ltd
Current assignee: China International Marine Containers Group Co Ltd; CIMC Enric Investment Holdings Shenzhen Co Ltd; Nantong CIMC Energy Equipment Co Ltd
Priority date: 2018-08-06
Filing date: 2018-08-06
Publication date: 2020-02-18
Anticipated expiration: 2038-08-06
Also published as: CN110802347B

Abstract

The invention discloses a welding back gas protection device which comprises a protection cover abutting against the inner surface of a cylinder. The invention also comprises at least two support frames, a center rod, a rotating mechanism and a start-stop control mechanism, wherein the at least two support frames are arranged in the cylinder body and can rotate along with the cylinder body in a first direction; the central rod is positioned on the axis of the cylinder body and is fixedly connected with at least two support frames; the rotating mechanism is rotationally connected with the central rod, the protective cover is connected with the upper end part of the rotating mechanism, the driving device is fixedly connected with the lower end part of the rotating mechanism, and the driving device drives the rotating mechanism to rotate towards the second direction; the start-stop control mechanism is fixedly connected to the rotating mechanism or the driving device and provides a start signal and a stop signal for controlling the driving device to drive the rotating mechanism to rotate towards the second direction.

Description

Welding back gas protection device

Technical Field

The invention relates to the field of metal welding, in particular to a back gas protection device for cylinder girth welding.

Background

In metal welding, the back of the weld must be provided with a gas shield to block the oxidizing effect of oxygen in the air on the weld. Generally, inert gases are considered to be a good protective medium. The gas protection device is often referred to herein as a "back gas protection device".

When the circular welding seam of the large-sized cylinder is welded, a back gas protection device is required to be arranged in the cylinder to prevent the circular welding seam from being oxidized.

Referring to fig. 1, in the prior art, a jack 103 is fixed on an arc plate 104, and a plurality of small bearings 105 are disposed below the arc plate 104, so that the arc plate 104 can slide in the cylinder 100. The other end of the jack 103 is connected to the gas shield 101 through a seamless steel pipe 102. During the operation, due to the out-of-round of the cylinder 100, the worker needs to continuously adjust the jack 103 up and down to make the gas protection cover 101 fit with the inner surface of the cylinder 100. Meanwhile, when the cylinder 100 rotates, the gas protection cover 101 also rotates together, and the worker needs to move the arc plate 104 at any time to enable the gas protection cover 101 to cover the welding position. Therefore, at least one worker is required to ensure the normal operation of the back gas protection device during the working process.

In addition, the inert gas in the cylinder 100 has higher concentration, which causes great harm to workers; and the rotation angle of the back gas protection device is manually operated, so that the gas protection cover 101 can be deviated or the interval is too large once a worker keeps his mind, and the circular seam forming is poor.

The above information disclosed in this background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not constitute prior art that is already known to a person of ordinary skill in the art.

Disclosure of Invention

The main purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art, and to provide a welding backside gas protection device with high welding quality without requiring special supervision in the barrel.

In order to achieve the purpose, the invention adopts the following technical scheme:

according to one aspect of the invention, the welding back gas protection device is used for back gas protection of cylinder welding, and comprises a protective cover which is abutted against the inner surface of a cylinder, the protective cover can be driven by a driving device to slide along the inner surface of the cylinder, and the welding back gas protection device further comprises at least two supporting frames, a central rod, a rotating mechanism and a start-stop control mechanism. At least two support frames are arranged in the cylinder body and can rotate along with the cylinder body in a first direction; the central rod is positioned on the axis of the cylinder body and is fixedly connected with at least two support frames; the rotating mechanism is rotationally connected with the central rod, the protective cover is connected with the upper end part of the rotating mechanism, the driving device is fixedly connected with the lower end part of the rotating mechanism, and the driving device drives the rotating mechanism to rotate towards a second direction; the start-stop control mechanism is fixedly connected with the rotating mechanism or the driving device and provides a start signal and a stop signal for controlling the driving device to drive the rotating mechanism to rotate towards the second direction.

According to an embodiment of the present invention, the start/stop control mechanism includes a mounting portion, a swing lever, a start switch, and a stop switch. The mounting part is fixedly connected with the rotating mechanism or the driving device; the swinging rod is hinged to the mounting part and can swing around a hinged point; the starting switch and the stopping switch are fixedly arranged on the mounting part and are respectively arranged on two sides of the swinging rod; when the swing rod triggers the starting switch, the driving device drives the rotating mechanism to rotate towards the second direction, and when the swing rod triggers the stopping switch, the driving device stops working.

According to an embodiment of the present invention, the mounting portion includes a vertical plate and two wing plates fixedly connected to or integrally formed with the vertical plate, the vertical plate is fixedly connected to the rotating mechanism or the driving device, and the two wing plates are vertically disposed at left and right ends of the vertical plate.

According to an embodiment of the present invention, the rotation mechanism is connected to the protective cover through an elastic member, and the elastic member provides an elastic force so that the protective cover is always kept in a state of being attached to the inner surface of the cylinder.

According to an embodiment of the invention, the elastic element is a compression spring.

According to an embodiment of the present invention, each of the supporting frames includes at least two supporting rods, one end of each of the at least two supporting rods is fixedly connected to the central rod, and the other end of each of the at least two supporting rods abuts against the inner surface of the cylinder.

According to an embodiment of the present invention, the number of the support rods is three, and the support rods are arranged on the same plane, and an included angle between each two support rods is 120 °.

According to an embodiment of the present invention, the movable rack comprises a number of movable rods corresponding to the number of the support rods, and the movable rods are connected to the support rods, so that the overall length of the support rods and the movable rods can be extended or shortened by moving the movable rods.

According to an embodiment of the present invention, the moving rod is a through-screw rod, and is screwed to the support rod.

According to an embodiment of the present invention, the device further includes a number of protection sleeves corresponding to the number of the support rods, and the protection sleeves are sleeved at the end of each moving rod contacting the cylinder.

According to an embodiment of the present invention, the protective cover is fan-shaped, and an opening is formed at an end facing the cylinder, and the radian of the surface of the opening matches with the radian of the inner surface of the cylinder.

According to an embodiment of the present invention, the protective cover further comprises a metal plate disposed inside the protective cover, wherein the metal plate is filled with holes at equal intervals for passing the protective gas.

According to an embodiment of the present invention, the metal plate is a copper plate.

According to one embodiment of the invention, heat-resistant sealing elastic strips are arranged around the opening and used for ensuring that the protective cover is abutted against the barrel without a gap; and pulleys are respectively arranged at four corners of the opening and used for reducing the friction force between the protective cover and the barrel.

According to the technical scheme, the welding back gas protection device has the advantages and positive effects that:

the start and stop of the driving device are automatically controlled by the start-stop control mechanism, so that the rotating mechanism is driven to rotate in a clearance manner, and the protective cover can continuously cover the position to be welded. In the whole welding process, workers do not need to participate in the cylinder, so that labor force is saved, and the harm of protective gas to the workers is avoided. Meanwhile, manual operation is replaced by machine operation, the protective cover is stably positioned, and the welding quality is greatly improved.

Drawings

Various objects, features and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, when considered in conjunction with the accompanying drawings. The drawings are merely exemplary of the invention and are not necessarily drawn to scale. In the drawings, like reference characters designate the same or similar parts throughout the different views.

FIG. 1 is a schematic view of a prior art welding backside gas shield.

FIG. 2 is a front view of a welding backside gas shield apparatus shown in accordance with an exemplary embodiment.

Fig. 3 is an enlarged view at a in fig. 2.

FIG. 4 is a schematic view of a mounting portion of a start stop control mechanism according to an exemplary embodiment.

Fig. 5 is a schematic diagram of a rotary mechanism shown according to an exemplary embodiment.

Fig. 6 is a side view of fig. 2.

Fig. 7 is an enlarged view at B in fig. 6.

Fig. 8 is a schematic view of a protective cover shown according to an exemplary embodiment.

FIG. 9 is a schematic view of a metal plate shown according to an exemplary embodiment.

FIG. 10 is a schematic view of a travel bar shown in accordance with an exemplary embodiment.

Wherein the reference numerals are as follows:

10. a protective cover; 11. a pulley; 12. heat resistant sealing elastic strips; 13. an opening; 14. a metal plate; 15. a hole; 20. a support frame; 21. a support bar; 22. a protective sleeve; 23. a center pole; 24. a travel bar; 25. rotating the handle; 30. a rotation mechanism; 31. mounting a plate; 32. a first cross bar; 33. a first vertical bar; 34. a second vertical bar; 35. a second cross bar; 40. a start-stop control mechanism; 41. an installation part; 411. a vertical plate; 412. a first wing plate; 413. a second wing plate; 42. a swing lever; 43. starting a switch; 44. a stop switch; 50. a drive device; 51. a motor; 52. a first-stage speed reducer; 53. a secondary speed reducer; 54. a third-stage speed reducer; 541. a bull gear; 542. a pinion gear; 100. a barrel; 101. a pneumatic protective cover; 102. seamless steel pipes; 103. a jack; 104. a circular arc plate; 105. and (5) a small bearing.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their detailed description will be omitted.

Although relative terms, such as "upper" and "lower," may be used in this specification to describe one element of an icon relative to another, these terms are used in this specification for convenience only, e.g., in accordance with the orientation of the examples described in the figures. It will be appreciated that if the device of the icon were turned upside down, the element described as "upper" would become the element "lower". Other relative terms, such as "top", "bottom", and the like, are also intended to have similar meanings. The terms "a," "an," "the," and "said" are used to indicate the presence of one or more elements/components/etc.; the terms "comprising" and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. other than the listed elements/components/etc.; the terms "first," "second," "third," and "fourth," etc. are used merely as labels, and are not limiting as to the number of their objects.

For convenience of description, the rotation direction of the cylinder 100 is opposite to the rotation direction of the rotation mechanism 30, and therefore the rotation direction of the cylinder 100 is defined as a first direction and the rotation direction of the rotation mechanism 30 is defined as a second direction. If the first direction is anticlockwise rotation, the second direction is clockwise rotation; if the first direction is clockwise rotation, the second direction is counterclockwise rotation.

The invention relates to a welding back gas protection device, which comprises the following steps: when the cylinder 100 rotates in the first direction, the rotation mechanism 30 rotates in the first direction along with the cylinder 100 due to the inertial force. Due to the gravity, the swing rod 42 swings around the hinge point, so as to trigger the start switch 43, control the driving device 50 to start, and drive the rotating mechanism 30 to drive the protective cover 10 to rotate along the second direction. After the rotating mechanism 30 rotates a certain angle, the swing rod 42 swings around the hinge point to the stop switch 44 under the action of gravity, and the stop switch 44 is triggered, so that the driving device 50 is controlled to stop working, and in such a reciprocating manner, the protection cover 10 can be automatically rotated without manual participation in the girth welding process of the cylinder 100, and the protection cover 10 can be kept in a state of covering the girth welding position all the time.

It should be understood that the weld back gas shield of the present invention is not limited to welding using a large cylinder girth, and is equally applicable to girth welding of small tanks or pipes. In particular, the diameter of the can body or pipe to be welded can be adapted by reducing the size of the corresponding parts.

In the following, some embodiments of the invention will be described in detail with reference to the accompanying drawings, and features of the embodiments described below may be combined with each other without conflict.

Referring to fig. 2, fig. 2 is a schematic view illustrating an operation state of an exemplary welding back gas protection device in the cylinder.

As shown in fig. 2, an embodiment of the present invention includes: the device comprises a protective cover 10, a support frame 20, a rotating mechanism 30, a driving device 50 and a start-stop control mechanism 40. The protective cover 10 is pressed against the inner surface of the cylinder 100 and can be driven to slide along the inner surface of the cylinder 100, so as to cover the position to be welded of the circular seam at any time. The supporter 20 is installed in the cylinder 100 and can rotate with the cylinder 100 in a first direction. The supporting frame 20 further comprises a central rod 23, and the central rod 23 is located on the axis of the cylinder 100 and fixedly connected to the supporting frame 20 in a penetrating manner. The rotating mechanism 30 is rotatably connected to the central rod 23, one end of the rotating mechanism 30 is connected to the protecting cover 10, and the other end of the rotating mechanism 30 is provided with a driving device 50 fixedly connected to the rotating mechanism 30, and the driving device 50 drives the rotating mechanism 30 to rotate in the second direction. The start-stop control mechanism 40 is fixedly connected to the rotating mechanism 30 or the driving device 50, and the start-stop control mechanism 40 provides a start signal and a stop signal to control the driving device 50 to drive the rotating mechanism 30 to rotate in the second direction.

As shown in fig. 3, the start-stop control mechanism 40 may be fixedly connected to the driving device 50, and it should be understood that the start-stop control mechanism 40 may be installed at other positions, such as the rotating mechanism 30. The start-stop control mechanism 40 may include a mounting portion 41, a swing lever 42, a start switch 43, and a stop switch 44. The start switch 43 and the stop switch 44 may be proximity switches. The mounting portion 41 may be fixedly connected to the driving device 50, and similarly, the mounting portion 41 may be mounted on the rotating mechanism 30. The swing lever 42 is hinged to the mounting portion 41, for example, by a pin or bolt mounted on the mounting portion 41, and can swing around the hinge point. It should be understood by those skilled in the art that the present invention is not limited to the particular articulation of sway bar 42. The start switch 43 and the stop switch 44 are fixedly mounted on the mounting portion 41 and are respectively disposed on both sides near the swing lever 42 so that the swing lever 42 can trigger the two switches during the left-right swing.

It should be understood that the present embodiment does not limit the specific installation positions of the start switch 43 and the stop switch 44, and the distances between the start switch 43 and the stop switch 44 and the swing lever 42 may be equal or different in a natural state. The start switch 43 and the stop switch 44 may be installed on the same horizontal plane or on different horizontal planes, for example, the start switch 43 is located on the left side of the swing lever 42 and the stop switch 44 is located on the right side of the swing lever 42. The two switches may be triggered by the swing lever 42 during the swing process.

Further, a person skilled in the art can determine the distance between the start switch 43 and the stop switch 44 and the swing lever 42 according to the covered length of the protection cover 10, thereby controlling the rotation angle of the rotation mechanism 30.

Referring to fig. 4, fig. 4 illustrates the structure of an exemplary mounting portion 41 of the present invention. The mounting portion 41 is substantially rectangular and includes a vertical plate 411 and two flanges fixedly connected to or integrally formed with the vertical plate 411. The riser 411 is fixedly mounted on the drive device 50, for example, by bolting, and two wings are provided at both left and right ends of the riser 411. The included angle between the two wings and the riser 411 may be a small obtuse angle or a large acute angle, and preferably, the two wings may be perpendicular to the riser 411. In the present embodiment, the shape of the wing is an isosceles trapezoid, but those skilled in the art should understand that the shape of the wing can be selected from various shapes, such as a square, a rectangle, a triangle, etc., and the shape of the wing can be used for installing the start switch 43 and the stop switch 44.

The rotary mechanism 30 will be described in detail below with reference to fig. 2, 5, and 6. As shown in fig. 5, the rotating mechanism 30 includes a mounting plate 31, a first cross bar 32, a first vertical bar 33, a second vertical bar 34, and a second cross bar 35. The cross bars and the vertical bars together form a substantially rectangular frame. The mounting plate 31 may be rectangular, or may have other shapes such as a square shape and a triangular shape. In the present embodiment, the mounting plate 31 is, for example, a rectangular plate. The mounting plate 31 is pivotally connected to the central rod 23, preferably by a bearing. The lower end of the mounting plate 31 is fixedly connected with a driving device 50, for example, but not limited thereto, by a bolt connection, and may be connected by welding or a snap connection. The first cross bar 32 is arranged transversely and fixedly connected to the mounting plate 31, for example by welding. Preferably, the structure of the mounting plate 31 and the first cross bar 32 is symmetrical with respect to the axis of the center rod 23.

The first vertical rod 33 and the second vertical rod 34 are respectively and fixedly connected to two ends of the cross rod in parallel, and meanwhile, the plane where the two vertical rods are located and the plane where the mounting plate 31 is located are the same plane. The plane of the rotating mechanism 30 composed of the cross rod and the vertical rod is ensured to be vertical to the central rod 23, and further, the plane of the rotating mechanism 30 is vertical to the axial lead of the cylinder 100. One end of the first and second

vertical rods

33 and 34 is connected to the bottom plate of the protective cover 10.

Further, the rotating mechanism 30 further comprises a second cross bar 35, the second cross bar 35 is transversely disposed at a position close to the protecting cover 10, and two ends of the second cross bar 35 are respectively and fixedly connected to the first vertical bar 33 and the second vertical bar 34, and preferably, the second cross bar 35 is parallel to the first cross bar 32. The second cross bar 35 ensures the stability of the first vertical bar 33 and the second vertical bar 34, and prevents the first vertical bar 33 and the second vertical bar 34 from shaking.

According to an embodiment of the present invention, the first vertical bar 33 and/or the second vertical bar 34 and/or the first horizontal bar 32 and/or the second horizontal bar 35 may be hollow tubular, so as to reduce the overall weight of the welding gas back protection device of the present invention, and facilitate the carrying of workers.

According to an embodiment of the present invention, one end of the first and second

vertical rods

33 and 34 may be connected to the protective cover 10 by an elastic member, such that the protective cover 10 always maintains a state of being attached to the inner surface of the cylinder 100, for example, the elastic member may be a compression spring, but is not limited thereto, and the elastic member may also be a metal bellows, etc.

The structure of the supporting frame 20 will be described in detail with reference to fig. 2 and 6. It should be understood that the number of the supporting frames is at least two, and may be three, four or more. The more than two support frames can ensure that the central rod 23 cannot tilt after the rotating mechanism 30 is installed. The supporting frame 20 includes at least two supporting rods 21 besides the central rod 23 located on the axial lead of the cylinder 100, one end of each supporting rod 21 is fixedly connected to the central rod 23, and the other end of each supporting rod 21 abuts against the inner surface of the cylinder 100. The specific number of the support rods 21 is not shown in the present embodiment, but those skilled in the art should understand that the number of the support rods 21 may be two, three, four, etc., or even multiple. Meanwhile, the three or more support rods 21 may be disposed in a coplanar manner or may be disposed in a non-coplanar manner. The included angles between the support rods 21 arranged in the same plane can be equal or unequal.

According to one embodiment of the present invention, as shown in fig. 2, preferably, three support rods 21 are used. Meanwhile, the three support rods 21 are coplanar, and the included angle between the support rods 21 is 120 °.

According to an embodiment of the present invention, the support frame further includes a number of moving rods 24 corresponding to the number of the support rods 21, the moving rods 24 are connected to the support rods 21, and by moving the moving rods 24, the overall length of the support rods 21 and the moving rods 24 can be extended or shortened accordingly, so that the support frame 20 can be installed in the cylinder bodies 100 with different diameters.

Further, in the embodiment, the specific connection manner between the moving rod 24 and the supporting rod 21 is not limited, and a person skilled in the art can select the moving rod 24 to be clamped to the supporting rod 21 according to design requirements, and the moving rod 24 is clamped to different positions of the supporting rod 21, so as to adjust the overall length of the moving rod 24 and the supporting rod 21. The moving rod 24 may also be screwed to the support rod 21. For convenience of explanation, the moving lever 24 will be schematically described below as an example of a feed screw. As shown in fig. 10, one end of the moving rod 24 has an external thread, which is screwed into the corresponding internal thread of the supporting rod 21, the rotating handle 25 is welded to the feed-through rod, and the rotating handle 25 is rotated to adjust the moving rod 24 to screw in or screw out the supporting rod 21, so as to adjust the supporting radius of the supporting frame 20, so that the supporting frame 20 can adapt to the cylinders 100 with different diameters.

According to an embodiment of the present invention, as shown in fig. 2, a protective sleeve 22 is further disposed at one end of the moving rod 24 contacting the cylinder 100, and preferably, the material of the protective sleeve 22 may be nylon. The protective sleeve 22 functions to prevent the inner wall of the cylinder 100 from being scratched by the moving rod 24.

According to an embodiment of the present invention, as shown in fig. 6, the number of the supporting frames 20 may be two. The supporting frames 20 may be crossed or overlapped as shown by the axial direction of the cylinder 100. In one embodiment of the present invention, the two sets of support frames 20 are arranged in an overlapping manner.

According to an embodiment of the present invention, as shown in fig. 7, the driving device 50 includes a motor 51, a speed reducer, a large gear 541, and a small gear 542. It should be understood that the speed reducer may be provided with a multi-stage speed reducer, such as a one-stage gear speed reducer, a two-stage gear speed reducer, etc., depending on the rotational speed of the motor 51 and the rotational speed required by the rotary mechanism 30. The large gear 541 is fixedly connected to the center rod 23, and the small gear 542 is fixedly connected to an output shaft of the speed reducer and is kept in mesh with the large gear 541. As an example, the motor 51 may be a direct current 24V motor. The rotation speed is reduced to a speed required for the rotation of the rotation mechanism 30 by the action of the one-stage or multi-stage speed reducer. Since the large gear 541 is fixedly connected to the central rod 23, the small gear 542 rotates and revolves around the central rod 23, thereby driving the rotating mechanism 30 to rotate in the second direction.

According to an embodiment of the present invention, the speed reducer may be a worm gear speed reducer because the worm gear speed reducer has a self-locking function such that the rotating mechanism 30 can only rotate in the second direction. In the working process or the carrying process, the worm gear reducer has a self-locking function, the rotating mechanism 30 is prevented from reversely rotating, the quality of a welding seam in the welding process is guaranteed, and the safety in the carrying process is also guaranteed.

According to an embodiment of the present invention, as shown in fig. 8, the protective cover 10 may be substantially fan-shaped, but is not limited thereto, and may be substantially rectangular, square, or the like, and preferably, the protective cover 10 in the present embodiment is fan-shaped. The fan-shaped protective cover 10 can enable protective gas to diffuse rapidly, and the contact area of the protective cover 10 and a welding seam is increased, so that the welding quality is guaranteed. The side of the protective cover 10 facing the cylinder 100 is provided with an opening 13, and in order to ensure that the protective cover 10 can be completely attached to the cylinder 100 and prevent the leakage of protective gas, the radian of the surface of the opening 13 is matched with the radian of the inner surface of the cylinder 100. The bottom wall of the protective cover 10 is further connected with a gas pipe (not shown) for passing protective gas, one end of the gas pipe is communicated with the protective cover 10, and the other end of the gas pipe can be connected with a hose for conveying protective gas.

According to an embodiment of the present invention, as shown in fig. 9, the protective cover 10 further includes a metal plate 14 disposed therein. The surface of the metal plate 14 is filled with equally spaced holes 15 for the passage of a shielding gas. The metal plate 14 with the holes 15 can make the protective gas at the position to be welded more uniform and better in protection effect. Preferably, the metal plate 14 may be a copper plate. In the welding process, the red copper plate is not easy to be broken by a plasma gun, and the omitted stainless steel solution is also cleaned from the red copper plate by a container. At the same time, the overall weight of the protective cover 10 can be made lighter, facilitating handling and transport.

According to an embodiment of the present invention, the heat-resistant sealing elastic strips 12 are disposed around the opening 13 of the protection cover 10, so as to ensure that the protection cover 10 is attached to the cylinder 100 without a gap, thereby preventing the leakage of the protection gas.

According to an embodiment of the present invention, as shown in fig. 2, pulleys 11 are attached to four corners of the opening 13 of the protective cover 10, so that the frictional force between the protective cover 10 and the cylindrical body 100 is reduced while the protective cover 10 is securely attached to the cylindrical body 100.

According to an embodiment of the present invention, the welding backside gas protection device of the present invention further comprises a camera mounted on the protection cover 10 for real-time feeding back the welding condition inside the cylinder 100 to the welding personnel outside the cylinder 100. If there is a problem, the welding personnel outside the cylinder 100 can process in time, thereby ensuring the welding quality and reducing the loss.

The working process of the welding back gas protection device of the invention is described in detail as follows:

after the welding back gas protection device is assembled, the rotating mechanism 30 drives the protective cover 10 to be at the 12-point position, the protective cover 10 covers the position to be welded, the swinging rod 42 naturally droops, and the driving device 50 does not work. After welding, the cylinder 100 slowly rotates in the first direction, so as to drive the rotating mechanism 30 and the protective cover 10 to slowly rotate in the same direction in the first direction, and the swing rod 42 swings around the hinge point towards the start switch 43 due to gravity, but the start switch 43 is not triggered yet.

When the rotating mechanism 30 rotates to the 11 o' clock position, the swing lever 42 triggers the start switch 43, and the start signal controls the driving device 50 to start, so as to drive the small gear 542 to rotate around the large gear 541, and drive the rotating mechanism 30 to rotate in the second direction. During the rotation, the protective cover 10 is moved to the unwelded part of the weld. At the same time, the swing lever 42 is also gradually disengaged from the start switch 43 and approaches toward the stop switch 44. When the rotation mechanism 30 rotates to the 1 o' clock position, the swing lever 42 activates the stop switch 44, and the stop signal controls the driving device 50 to stop, so that the rotation mechanism 30 stops rotating.

The cylinder 100 rotates towards the first direction uninterruptedly in the welding process, the rotating mechanism 30 rotates from the 1 o 'clock position to the 11 o' clock position gradually, and the circular reciprocating operation is carried out, so that the circular seam welding of the cylinder 100 is realized.

In conclusion, the welding back gas protection device has the advantages and positive effects that:

the start and stop of the driving device 50 are automatically controlled by the start-stop control mechanism 40, so that the rotating mechanism 30 is driven to rotate in a clearance manner, and the protective cover 10 can continuously cover the position to be welded. In the whole welding process, workers do not need to participate in the cylinder body 100, so that labor force is saved, and the harm of protective gas to the workers is avoided. Meanwhile, manual operation is replaced by machine operation, the protective cover 10 is stably positioned, and the welding quality is greatly improved.

It is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth herein. The invention is capable of other embodiments and of being practiced and carried out in various ways. The foregoing variations and modifications fall within the scope of the present invention. It will be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention.

Claims

1. The utility model provides a welding back of body gas protection device for barrel welded back of body gas protection, including support push up in the safety cover of barrel internal surface, the safety cover can be followed by a drive arrangement drive the barrel internal surface slides, its characterized in that, welding back of body gas protection device still includes:

the at least two supporting frames are arranged in the cylinder body and can rotate along with the cylinder body in a first direction;

the central rod is positioned on the axis of the cylinder body and is fixedly connected with at least two support frames;

the protective cover is connected to the upper end part of the rotating mechanism, the driving device is fixedly connected to the lower end part of the rotating mechanism, and the driving device drives the rotating mechanism to rotate towards a second direction;

and the start-stop control mechanism is fixedly connected with the rotating mechanism or the driving device and provides a start signal and a stop signal for controlling the driving device to drive the rotating mechanism to rotate towards the second direction.

2. The welding backing gas shield of claim 1, wherein said start-stop control mechanism comprises:

the mounting part is fixedly connected with the rotating mechanism or the driving device;

the swinging rod is hinged to the mounting part and can swing around a hinged point;

the starting switch and the stopping switch are fixedly arranged on the mounting part and are respectively arranged on two sides of the swinging rod;

when the swing rod triggers the starting switch, the driving device drives the rotating mechanism to rotate towards the second direction, and when the swing rod triggers the stopping switch, the driving device stops working.

3. The welding gas back protection device of claim 2, wherein the mounting portion comprises a vertical plate and two wing plates fixedly connected to or integrally formed with the vertical plate, the vertical plate is fixedly connected to the rotating mechanism or the driving device, and the two wing plates are vertically arranged at the left end and the right end of the vertical plate.

4. The welding gas shield apparatus of any of claims 1-3 wherein the rotation mechanism is coupled to the shield by a resilient member that provides a spring force that maintains the shield in engagement with the inside surface of the barrel at all times.

5. The welding backing gas shield of claim 4 wherein said resilient member is a compression spring.

6. The welding gas back protection device of any one of claims 1-3, wherein each support frame comprises at least two support rods, one end of each support rod is fixedly connected to the central rod, and the other end of each support rod abuts against the inner surface of the cylinder.

7. The welding gas shield of claim 6 wherein said support rods are three and are disposed in a common plane, and wherein the angle between each of said support rods is 120 °.

8. The welding gas back protection device of claim 6, comprising a number of moving rods corresponding to the number of the support rods, connected to the support rods, wherein the moving rods are moved to make the overall length of the support rods and the moving rods correspondingly longer or shorter.

9. The welding backing gas shield of claim 8 wherein said travel bar is a feed bar threadably connected to said support bar.

10. The welding gas back protection device of claim 8, further comprising a number of protection sleeves corresponding to the number of the support rods, and the protection sleeves are sleeved on the end of each moving rod, which is in contact with the cylinder body.

11. The weld back gas shield apparatus of any of claims 1-3, wherein the shield has a fan shape with an opening at an end facing the barrel, the opening having a face with a curvature that matches the curvature of the inner surface of the barrel.

12. The welding gas shield of claim 11, further comprising a metal plate disposed within said shield, said metal plate surface being perforated with equally spaced holes for passage of shield gas.

13. The welding backing gas shield of claim 12, wherein said metal plate is a copper plate.

14. The welding gas shield of claim 11 wherein said opening is surrounded by heat resistant sealing strips for securing said shield against said barrel without gaps; and pulleys are respectively arranged at four corners of the opening and used for reducing the friction force between the protective cover and the barrel.