CN108568467B

CN108568467B - Stretch bending tire device for limiting side bending of curved beam of railway vehicle roof

Info

Publication number: CN108568467B
Application number: CN201710151004.3A
Authority: CN
Inventors: 朱丽娟; 王敏; 吕义; 谷诤巍; 何玲玲
Original assignee: Jilin University
Current assignee: Jilin University
Priority date: 2017-03-14
Filing date: 2017-03-14
Publication date: 2021-01-26
Anticipated expiration: 2037-03-14
Also published as: CN108568467A

Abstract

The invention provides a stretch bending tire device which is used for limiting the side bending of a curved beam at the top of a railway vehicle. Compared with the prior art, the stretch bending tire device capable of limiting the side bending of the railway vehicle roof camber beam effectively controls the defects of side bending and section distortion in the stretch bending forming of the railway vehicle roof camber beam type component, eliminates the defect problem which cannot be solved by using the traditional stretch bending tire, greatly improves the forming precision of the component, shortens the production period and reduces the production cost.

Description

Stretch bending tire device for limiting side bending of curved beam of railway vehicle roof

Technical Field

The invention relates to a stretch bending tire device capable of limiting side bending of a curved beam at the top of a railway vehicle, which is mainly used for the stretch bending forming process of the curved beam type components at the top of the railway vehicle and belongs to the technical field of bending forming.

Background

Rail transit is one of the most important transportation modes in China. The framework members on the rail vehicles are generally large in size, and bending forming of the profiles is mainly performed by using a stretch bending technology. Stretch-bending is a cold working method in which a workpiece is bent while a tangential tensile force is applied to the workpiece, and the workpiece is formed under the combined action of a bending moment and the tensile force. The stress in the cross section of the workpiece is mainly the tensile stress during the stretch bending forming, so that the stretch bending formed workpiece has the advantages of small resilience, good part die attachment, high forming precision and good surface quality.

The side view of a blank of a camber beam for a railway vehicle roof is shown in figure 1, the main body of the blank is an L-shaped stainless steel section which consists of a vertical edge and a chord edge, the vertical edge has the size of b, the chord edge has the size of H, the thickness of the section is t, before stretch bending treatment, the blank of the railway vehicle roof camber beam shown in figure 1 is a section structure which is vertically stretched along the cross section of the blank, according to design requirements, the blank needs to be stretch bent into the shape of the camber beam structure shown in figure 2, in the stretch bending process, the cross section shown in figure 1 is kept unchanged, the blank needs to be stretch bent into the shape of three arc sections, the radius of a large arc section is R, the radius of two small arc sections is R, the overall length of the camber beam is L, and the height of the camber beam is H.

The traditional stretch bending mould has a too simple structure, and the moulding surface of the mould is similar to the structure of a stretch bending piece, namely the curvature radius of a middle large arc section is large, and the curvature radius of two end small arc sections is small. The gap between the baffle plates on the traditional stretch bending tire is fixed, theoretically, the smaller the gap between the baffle plates and the profile is, the better the gap is, in the actual situation, when the baffle plates are in contact with the profile, namely, the gap is 0mm, the friction force is increased in the stretch bending process, the profile cannot be completely attached to the mold, the bending beam precision is extremely poor, and therefore, in the actual situation, the gap is formed between the baffle plates and the profile, so that although the bending beam is well attached to the stretch bending tire, the side bending and section twisting defects can occur after the bending beam is taken out of the stretch bending tire, as shown in fig. 3 and fig. 4, the solid line represents a bending beam without defects, the dotted line represents a bending beam with defects of side bending and section twisting defects, and the dotted line represents a bending beam with defects of side bending and section twisting defects due to the gap between the baffle plates and the profile, no pressure is applied to the side of the profile.

In order to solve the defects in the traditional stretch bending tire forming process, the invention discloses a stretch bending tire device capable of limiting the lateral bending of a bending beam. A device capable of automatically adjusting the gap between a baffle and a section is arranged on a traditional stretch bending tire, the gap between the baffle and the section is 0.8 t-1.1 t in the pre-stretching and cladding stretching stages, the baffle continuously moves towards the section before the repair-stretching stage, the gap between the baffle and the section is 0mm, then repair-stretching is carried out, after the repair-stretching is finished, the baffle starts to apply lateral pressure on the section to enable a bent beam to reach the yield limit, finally the bent beam is unloaded and taken out, the springback can be reduced, the defects of lateral bending and section distortion of the bent beam are eliminated, and the product quality and the forming precision of a formed part are improved.

Disclosure of Invention

In view of the above-mentioned drawbacks, the technical problem solved by the present invention is to control the side bending defects of the roof camber beam member occurring during the stretch-bending process.

The invention provides a stretch bending tire device which is used for limiting the side bending of a curved beam at the top of a railway vehicle.

Preferably, the fixing plate is fastened to the stretch-bending tire main body by means of a bolt connection.

Preferably, the piston rod comprises a telescopic rod and a fixing rod.

Preferably, holes are formed in the telescopic rod and the fixing rod.

Preferably, the baffle, the piston rod and the fixing plate are connected through a fastener, and the fastener is matched with holes in the telescopic rod and the fixing rod.

Preferably, the fastener is a bolt.

Compared with the prior art, the stretch bending tire device freely controls the gap between the baffle and the section bar through the piston rod in the stretch bending process, before the repair-drawing stage, the baffle continuously moves towards the section bar, so that the gap between the baffle and the section bar is 0mm, then repair-drawing is carried out, after the repair-drawing is finished, the baffle starts to apply lateral pressure to the section bar, so that the bent beam reaches the yield limit, finally the bent beam is unloaded and taken out, the springback can be reduced, the defects of lateral bending and section distortion of the bent beam are overcome, and the product quality and the forming precision of a formed part are improved.

The stretch bending tire device capable of limiting the side bending of the railway vehicle roof camber beam effectively controls the defects of side bending and section distortion in stretch bending forming of railway vehicle roof camber beam type components, eliminates the defect problem which cannot be solved by using a traditional stretch bending tire, greatly improves the forming precision of the components, shortens the production period and reduces the production cost; meanwhile, the structure can be popularized and applied to stretch bending clamping fixtures of other components, and has very important practical significance and use value.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a side view of a blank for a camber beam;

FIG. 2 is a front view of the beam as formed;

FIG. 3 is a top view of a comparison of the presence or absence of a side bend defect in a formed beam;

FIG. 4 is a schematic cross-sectional view with a cross-sectional twist at A in FIG. 3;

FIG. 5 is a schematic view of a stretch bending tire assembly for limiting lateral bending of a curved roof rail of a railway vehicle according to the present invention;

FIG. 6 is a schematic partial cross-sectional view taken at B-B of FIG. 5;

FIG. 7 is a front view of the piston rod;

fig. 8 is a side view of the piston rod.

In FIGS. 1-8:

1. curved beam section 2, stretch bending tire main body 3, section bar 4, baffle 5, bolt 6, piston rod 61, telescopic rod 62, fixed rod 7 and fixed plate

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 5-8, the present embodiment provides a stretch bending tire device capable of limiting the lateral bending of a curved beam on a roof of a railway vehicle, which is provided with a mechanism capable of automatically adjusting the gap between baffles, and the mechanism comprises a stretch bending tire main body (2), a baffle (4), a piston rod (6), a fixing plate (7) and the like, wherein the fixing plate (7) is fastened on the stretch bending tire main body (2) in a bolt connection manner. The telescopic rod (61) and the fixed rod (62) in the piston rod (6) are provided with holes, and the size of the holes is just matched with the bolt (5).

The piston rod (6) is arranged in the fixed plate (7) and can extend and shorten. The fixed plate (7) is connected with electric power to drive the piston rod (6) to operate.

The baffle (4), the piston rod (6) and the fixing plate (7) are connected together through the bolt (5), and the baffle (4) can extrude and loosen the section bar (3) along with the extension and the shortening of the piston rod (6).

According to the contour and section size data of a vehicle roof camber beam component, a stretch bending tire main body and a mold surface are designed, after a section (3) is placed on a stretch bending tire main body (2), a gap between a baffle (4) and the section (3) is adjusted through a piston rod (6), the gap between the baffle and the section is 0.8 t-1.1 t, then a stretch bending process is started, in the pre-stretching and cladding stretching stages, the gap between the baffle (4) does not need to be adjusted, after the section (3) is completely attached to a mold, namely after cladding stretching, before repair stretching, the gap between the baffle (4) and the section (3) is adjusted through the piston rod (6), then repair stretching is carried out, after the repair stretching is finished, the section (3) is extruded, the section (3) is subjected to side pressure, the camber beam reaches the yielding limit, and finally unloading is started.

The invention provides a stretch bending tire device capable of limiting the side bending of a curved beam at the top of a railway vehicle, which effectively controls the defects of side bending and section distortion in the stretch bending forming of the curved beam type components at the top of the railway vehicle, eliminates the defect problem which cannot be solved by the traditional stretch bending tire, greatly improves the forming precision of the components, shortens the production period and reduces the production cost; meanwhile, the structure can be popularized and applied to stretch bending clamping fixtures of other components, and has very important practical significance and use value.

Claims

1. A stretch-bending tire apparatus for limiting lateral bending of a roof bow of a railway vehicle, the apparatus comprising:

stretch-bending the tire main body;

a baffle plate;

the fixing plate is connected to the stretch bending tire main body;

a piston rod telescopically mounted in the fixing plate;

the method comprises the steps that a baffle is connected with a piston rod, electric power is connected into a fixing plate to enable the piston rod to run, a section with an L-shaped section is placed on a stretch bending tire main body, a gap between the baffle and the section is adjusted through the piston rod to enable the gap between the baffle and the section to be 0.8 t-1.1 t, wherein t is the thickness of the section, then a stretch bending process is started, the gap between the baffle and the section does not need to be adjusted in the pre-stretching and cladding stretching stages, after the section is completely attached to a mold, namely after cladding stretching and before redrawing, the gap between the baffle and the section starts to be adjusted through the piston rod to enable the gap between the baffle and the section to be 0mm, then redrawing is carried out, after the redrawing, the baffle starts to apply lateral pressure to the section to enable a bent beam to reach a yield limit.

2. A stretch-bending tire apparatus according to claim 1, wherein: the fixed plate is fastened on the stretch bending tire main body in a bolt connection mode.

3. A stretch-bending tire apparatus according to claim 1, wherein: the piston rod comprises a telescopic rod and a fixed rod.

4. A stretch-bending tire apparatus according to claim 3, wherein: holes are arranged in the telescopic rod and the fixed rod.

5. A stretch-bending tire apparatus according to claim 4, wherein: the baffle, the piston rod and the fixing plate are connected through a fastener, and the fastener is matched with holes in the telescopic rod and the fixing rod.

6. A stretch-bending tire apparatus according to claim 5, wherein: the fastener is a bolt.