A bending fixture

Abstract

A bending fixture for bending a fusible link includes: a punch, a die, a positioning element, and a resetting element. The punch is reciprocally positioned above the die, and a forming protrusion with a shape that is wider at the top and narrower at the bottom is provided at the lower end of the punch. The die includes a first bending cavity and a second bending cavity. The upper surface of the second bending cavity has a second forming groove recessed corresponding to the shape of the forming protrusion. The first bending cavity is vertically and vertically positioned within the second forming groove. The upper surface of the first bending cavity has a straight first forming groove recessed corresponding to the lower tip of the forming protrusion. The depth of the first forming groove is shallower than that of the second forming groove, and the first forming groove is located in the center of the second forming groove. The positioning element is used to fix the fusible link onto the die. The resetting element is used to reset the positioning element. Therefore, the bending fixture can precisely control the bending operation process and protect the narrow neck.

Description

Technical Field

[0001] This utility model relates to the field of machining, and more specifically to a bending fixture. Background Technology

[0002] In current fuse manufacturing, to save costs, long strip fuses often employ a two-stage resistance welding lap joint process. (See [reference needed]). Figure 1 This is a schematic diagram of the structure of the elongated fusible link 1 after resistance welding (without bending). The overlapping portion L has a double-layer structure. Simultaneously, to meet the requirement that the fusible link 1 needs to have a certain resistance to thermal shock to ensure stability and service life under complex working conditions, the fusible link 1' needs to be equipped with a bending structure 11'. (See reference...) Figure 2 This is a schematic diagram of the structure of the long strip-shaped fuse 1' after bending. The bending structure 11' is generally located between two adjacent narrow necks 12' on the fuse 1'. The lowest point of the bending structure 11' is located at the midpoint between the two narrow necks 12'. The cross-section of the entire bending structure 11' is an isosceles triangle shape and is symmetrically distributed between the two narrow necks 12'.

[0003] However, in actual production, it was found that in the elongated fuse 1', because the overlapping part L has a double-layer structure, compared with other single-layer parts, the uneven distribution of material and stress in the overlapping part L due to resistance welding results in differences in the mechanical properties of the overlapping part L. (See reference...) Figure 3 When the equipment bends the overlapping part L, the bending structure 11' is prone to shift towards one side of the narrow neck 12', causing the bending structure 11' between the two narrow necks 12' to be asymmetrical, affecting the forming accuracy of the elongated fuse body 1'. In addition, since the narrow neck 12' is a key weak point on the fuse body 1' used for precise fusing, the problem of the overlapping part L not being able to accurately bear force during the bending operation may also cause the narrow neck 12' on the offset side of the bending structure 11' to bear additional stress, causing damage to the narrow neck 12' and reducing the quality and reliability of the fuse body. Utility Model Content

[0004] The purpose of this utility model is to provide a bending fixture that can precisely control the bending operation process and protect the narrow neck.

[0005] To achieve the above objectives, this utility model provides a bending fixture for bending fused bodies, comprising: a punch, a die, a positioning component, and a resetting component; The punch is reciprocatingly positioned above the die, and a forming protrusion is provided at the lower end of the punch, which is wider at the top and narrower at the bottom. The die includes a first bending cavity and a second bending cavity. The upper surface of the second bending cavity is recessed with a second forming groove corresponding to the shape of the forming protrusion. The first bending cavity is vertically and vertically disposed in the second forming groove. The upper surface of the first bending cavity is recessed with a straight first forming groove corresponding to the lower tip of the forming protrusion. The depth of the first forming groove is shallower than that of the second forming groove and the first forming groove is located in the center of the second forming groove. The positioning element is used to fix the fuse body onto the die. The reset component is used to reset the positioning component.

[0006] Furthermore, the positioning component and the resetting component are disposed on the die cavity, the punch moves downward until the forming protrusion is embedded in the second forming groove, the first bending cavity, the positioning component and the resetting component are pressed down by the punch to a position below the bottom surface of the second forming groove, and the first bending cavity, the positioning component and the resetting component can move upward to reset.

[0007] Furthermore, a support base is provided below the die cavity, and the support base is provided with a clearance space corresponding to the position of the second forming groove. The lower ends of the first bending cavity, positioning component, and resetting component protrude from the die cavity and move up and down within the clearance space.

[0008] Furthermore, the support base is provided with a first receiving hole and a second receiving hole at the bottom. The first receiving hole and the second receiving hole are connected upward to the clearance space and are respectively positioned to correspond to the first bending cavity and the reset component. The first receiving hole and the second receiving hole are respectively provided with a first elastic component and a second elastic component. The first elastic component is connected to the lower end of the first bending cavity for resetting the first bending cavity, and the second elastic component is connected to the lower end of the reset component for resetting the reset component.

[0009] Furthermore, the positioning component is fixedly connected to the reset component. The initial position of the reset component is higher than that of the positioning component. The reset component drives the positioning component to be pressed down by the punch. The second elastic component is used to reset the reset component and thus trigger the reset positioning component.

[0010] Furthermore, the second forming groove is provided with a through hole that connects to the clearance space and is coaxial with the second receiving hole. The reset member is a column, and the height of the top of the reset member is not lower than the top edge of the second forming groove. The lower end of the reset member passes through the through hole and is located in the clearance space. The positioning member includes a positioning base and two positioning pins on the positioning base. The upper ends of the two positioning pins protrude from the upper surface of the second bending cavity and are located on both sides of the second forming groove. The positioning base is located in the clearance space and is fixedly connected to the reset member. The second elastic member is a spring with both ends abutting against the second receiving hole and the bottom surface of the positioning base, respectively. The lower end of the first bending cavity is a columnar structure. An abutting platform is protruding between the columnar structure and the first forming groove. The first elastic member is a spring with both ends abutting against the first receiving hole and the bottom surface of the abutting platform, respectively.

[0011] Furthermore, the formed protrusion is in the shape of an isosceles triangular prism.

[0012] Furthermore, the punch is mounted on a support, and a cylinder on the support drives the punch to reciprocate. A limiting block is protruding from the rear end of the punch, and a limiting crossbar is provided on the support. When the punch descends to the lowest position, the limiting crossbar stops the limiting block from moving downward.

[0013] Furthermore, the die has weld support plates of uniform height extending horizontally on both sides.

[0014] Furthermore, the punch forms upper pressure plates on both sides of the forming protrusion, and the second bending cavity forms lower support plates on both sides of the second forming groove corresponding to the upper pressure plates. When the punch moves downward until the forming protrusion is embedded in the second forming groove, the upper pressure plate presses on the lower support plate.

[0015] With the above solution, the die of this utility model is divided into a first bending cavity and a second bending cavity. The first bending cavity and the second bending cavity are respectively formed with a first forming groove and a second forming groove, and the first bending cavity is located in the second forming groove in a height-adjustable manner. During bending, the fuse to be bent is placed on the cavity and positioned by the positioning component. When the punch moves downward, it can be moved downward in two stages. The first movement uses the bottom tip of the forming punch to initially bend the fuse in the first forming groove of the first bending cavity. Then, the second movement presses the fuse, along with the first bending cavity, the positioning component, and the reset component, into the second forming groove, so that the fuse is bent and formed a second time in the second forming groove. After bending is completed, the punch moves upward, the reset component moves upward and resets, and pushes the fuse out of the second forming groove.

[0016] Therefore, when the overlapping portion of the fused body with the overlapping portion is bent according to this utility model, the following beneficial effects are achieved: 1. The first forming groove first provides local rigid constraint to the fused body to counteract the offset trend caused by uneven overlap. Then, the second forming groove is used for overall coordinated correction to ensure that the bend at the overlap is centered between the two narrow necks, solving the problem that traditional fixtures may cause bend offset and ensuring bend accuracy.

[0017] 2. Segmented bending deformation allows for precise positioning of the bending area and reasonable distribution of stress during the deformation process, preventing damage to the narrow neck due to displacement or stress concentration, ensuring the integrity of the fuse, and improving the quality and reliability of the fuse.

[0018] 3. The die and punch have simple structures, good compatibility with existing presses and other equipment, and are easy to produce, apply and promote. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a long strip-shaped fuse (without bending).

[0020] Figure 2 This is a schematic diagram of the structure after the overlapping part of the long strip-shaped fuse is bent normally.

[0021] Figure 3 Schematic diagram of the structure after abnormal bending of the overlapping part of the long strip fuse. Figure 4 This is a three-dimensional structural diagram of the present invention.

[0022] Figure 5 This is a partial enlarged view (a) of the present invention.

[0023] Figure 6 This is a partial enlarged view (II) of the present invention. Figure 7 This is a cross-sectional view of the present invention.

[0024] Explanation of icon numbers: L-shaped overlap; 1' fuse element; 11' bent structure; 12' narrow neck; 1. Punch; 11. Forming punch; 12. Upper pressure plate; 13. Limiting block 2. Die cavity; 21. First bending cavity; 211. First forming groove; 212. Abutment platform; 22. Second bending cavity; 221. Second forming groove; 23. Lower support plate; 3. Positioning component; 31. Positioning base; 32. Positioning column; 4. Reset components; 5 Support base; 51 Clearance space; 52 First receiving hole; 53 Second receiving hole; 54 First elastic element; 55 Second elastic element; 6 brackets; 61 cylinders; 62 limit crossbars; 7. Fuse support plate; 8. Base plate. Detailed Implementation

[0025] To further explain the technical solution of this utility model, the following detailed description is provided through specific embodiments.

[0026] A bending fixture provided by this utility model, see reference. Figures 4 to 6 This is an embodiment of the present utility model, which is disposed on the base plate 8 and can be placed on the machine platform, including: punch 1, die 2, positioning member 3, and resetting member 4; The punch 1 is reciprocatingly positioned above the die 2. A forming protrusion 11 is protruding from the lower end of the punch 1. The forming protrusion 11 can be an isosceles triangular prism shape that is wider at the top and narrower at the bottom. The die 2 includes a first bending cavity 21 and a second bending cavity 22. The upper surface of the second bending cavity 22 is recessed with a second forming groove 221 corresponding to the shape of the forming protrusion 11. The first bending cavity 21 is vertically and vertically disposed in the second forming groove 221. The upper surface of the first bending cavity 21 is recessed with a straight first forming groove 211 corresponding to the lower tip of the forming protrusion 11. The depth of the first forming groove 211 is shallower than that of the second forming groove 221 and the first forming groove 211 is located in the center of the second forming groove 221. Positioning element 3 is used to fix the fuse body on the die 2; Reset component 4 is used to reset positioning component 3.

[0027] The specific parameters of the forming protrusion 11, as well as the specific parameters of the first forming groove 211 and the second forming groove 221, can be set according to the size requirements of different fuses, and are not limited to isosceles triangular prisms.

[0028] In this embodiment, the positioning element 3 and the resetting element 4 are disposed on the die 2. The die 2 has fusible body support plates 7 with the same height and extending horizontally on both sides. When the fusible body is bent, both ends are supported on the fusible body support plates 7. A support base 5 is supported below the die 2. The support base 5 has a clearance space 51 at the position corresponding to the second forming groove 221. The lower ends of the first bending cavity 21, the positioning element 3, and the resetting element 4 pass through the die 2 and move up and down within the clearance space 51.

[0029] See Figure 7 Specifically, the support base 5 has a first receiving hole 52 and a second receiving hole 53 at its bottom. The first receiving hole 52 and the second receiving hole 53 connect upwards to the clearance space 51 and are positioned corresponding to the first bending cavity 21 and the reset member 4, respectively. The first receiving hole 52 and the second receiving hole 53 are respectively provided with a first elastic member 54 and a second elastic member 55. The first elastic member 54 is connected to the lower end of the first bending cavity 21 for resetting the first bending cavity 21, and the second elastic member 55 is connected to the lower end of the reset member 4 for resetting the reset member 4, thereby triggering the reset positioning member 3.

[0030] The second forming groove 221 is provided with a through hole that connects to the clearance space 51 and is coaxial with the second receiving hole 53. The reset member 4 is a column and passes through the second forming groove 221. The top of the reset member 4 is slightly higher than the top edge of the second forming groove 221. The lower end of the reset member 4 passes through the through hole and is located in the clearance space 51. The second receiving hole 53 passes through the lower half of the support base 5.

[0031] Positioning component 3 includes a positioning base 31 and two positioning posts 32 disposed on the positioning base 31. The upper ends of the two positioning posts 32 extend through the upper surface of the second bending cavity 22 and are located on both sides of the second forming groove 221. The edge of the narrow neck of the fuse body is provided with a semi-circular groove (the structure of the fuse body can be referred to). Figure 1The two positioning pins 32 are respectively embedded in the grooves of two adjacent narrow necks to achieve positioning. The initial position of the upper end of the reset member 4 is higher than the positioning pin 32 of the positioning member 3, and the reset member 4 and the fuse are respectively located on both sides of the positioning pin 32. The reset member 4 does not interfere with the placement of the fuse. The positioning base 31 is located in the clearance space 51 and is fixedly connected to the reset member 4. When the punch 1 presses down, it first contacts the higher reset member 4 and presses down the reset member 4. The positioning member 3 is moved downward by the reset member 4. The second elastic member 55 is a spring. A step is provided around the second receiving hole 53. The two ends of the second elastic member 55 abut against the step in the second receiving hole 53 and the bottom surface of the positioning base 31, respectively. That is, the positioning member 3 is fixedly connected to the reset member 4. The reset member 4 and the positioning member 3 move synchronously. The second elastic member 55 is used to reset the reset member 4 and the positioning member 3 at the same time.

[0032] The upper end of the first bending cavity 21 is a first forming groove 211 that is flush with the upper end of the second bending cavity 22, and the lower end is a columnar structure that extends out of the bottom of the second forming groove 221 and is located in the clearance space 51. An abutment platform 212 is provided between the columnar structure and the first forming groove 211. The abutment platform 212 is also located in the clearance space 51. The first elastic member 54 is a spring, and the two ends of the first elastic member 54 abut against the first receiving hole 52 and the bottom surface of the abutment platform 212, respectively.

[0033] In the initial state (the upper end of the first bending cavity 21 is flush with the upper end of the second bending cavity 22), the springs of the first elastic element 54 and the second elastic element 55 are in their natural state or compressed state. Therefore, after being pressed down, they always maintain an upward reset tendency. When the pressure above is lost, the first elastic element 54 and the second elastic element 55 extend upward to reset the first bending cavity 21, the positioning element 3, and the reset element 4.

[0034] In this embodiment, when bending is performed, the punch 1 moves downward until the forming protrusion 11 is embedded in the second forming groove 221. The first bending cavity 21, the positioning member 3, and the resetting member 4 are pressed down by the punch 1 to a position below the bottom surface of the second forming groove 221. The first bending cavity 21, the positioning member 3, and the resetting member 4 can be repositioned upward by the elastic potential energy of the first elastic member 54 and the second elastic member 55.

[0035] Furthermore, the punch 1 has upper pressure plates 12 formed on both sides of the forming protrusion 11, and the second bending cavity 22 has lower support plates 23 formed on both sides of the second forming groove 221 corresponding to the upper pressure plates 12. When the punch 1 moves downward until the forming protrusion 11 is embedded in the second forming groove 221, the upper pressure plate 12 presses on the lower support plate 23, and the parts on both sides of the fuse that are not bent are sandwiched between the upper pressure plate 12 and the lower support plate 23.

[0036] In this embodiment, the punch 1 is mounted on the support 6, and the support 6 is equipped with a cylinder 61 that drives the punch 1 to reciprocate. A limiting block 13 protrudes from the rear end of the punch 1, and a limiting crossbar 62 is provided on the support 6. When the punch 1 descends to its lowest position, the limiting crossbar 62 stops the limiting block 13 from moving downward, preventing excessive displacement of the punch 1 and resulting collision damage. The cylinder 61 can be connected to an external power source and controlled to control the lifting and lowering action of the punch 1.

[0037] Specifically, the special structure of this embodiment is that the die 2 is divided into a first bending cavity 21 and a second bending cavity 22. The first bending cavity 21 and the second bending cavity 22 are respectively formed with a first forming groove 211 and a second forming groove 221, and the first bending cavity 21 is located in the second forming groove 221 in a vertically movable manner.

[0038] When bending is performed using the bending fixture of this embodiment, the fuse to be bent is placed on the cavity and positioned using the positioning member 3, so that the midpoint between the two narrow necks corresponds to the first forming groove 211. When the punch 1 moves downward, the punch 1 is controlled to move downward in two segments. The first movement uses the bottom tip of the forming protrusion 11 to initially bend the fuse in the first forming groove 211 of the first bending cavity 21. Then, the second movement presses the fuse, together with the first bending cavity 21, the positioning member 3, and the reset member 4, down into the second forming groove 221, so that the fuse is bent and formed in the second forming groove 221. After bending is completed, the punch 1 moves upward, the reset member 4 moves upward to reset and pushes the fuse away from the second forming groove 221.

[0039] Since the first forming groove 211 is used to perform preliminary bending during bending to locate the midpoint between the two narrow necks, the bottom tip of the forming protrusion 11 can be positioned at the midpoint between the two narrow necks (i.e., the position of the preliminary bending) during the second displacement of the punch 1. Then the fuse is bent, which can better ensure that the lowest point of the bent part is at the midpoint between the two narrow necks.

[0040] In particular, when the bending fixture of this embodiment is used to bend the overlapping part of the fused body with overlapping part, the first forming groove 211 first provides local rigid constraint to the fused body to counteract the offset trend caused by uneven overlapping, and then the second forming groove 221 is used for overall coordinated correction to ensure that the bending at the overlapping part is centered between the two narrow necks, solving the problem that the traditional fixture may cause bending offset and ensuring bending accuracy.

[0041] The segmented bending deformation of the punch 1 can accurately locate the bending part and reasonably disperse the stress during the deformation process, avoiding damage to the narrow neck due to displacement and stress concentration, ensuring the integrity of the fuse, and improving the quality and reliability of the fuse.

[0042] Furthermore, the die 2 and punch 1 have simple structures, good compatibility with existing presses and other equipment, and are easy to produce, apply and promote.

[0043] The above is merely one embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A bending fixture for bending fuse bodies, characterized in that, include: Punch, die, positioning component, resetting component; The punch is reciprocatingly positioned above the die, and a forming protrusion is provided at the lower end of the punch, which is wider at the top and narrower at the bottom. The die includes a first bending cavity and a second bending cavity. The upper surface of the second bending cavity is recessed with a second forming groove corresponding to the shape of the forming protrusion. The first bending cavity is vertically and vertically disposed in the second forming groove. The upper surface of the first bending cavity is recessed with a straight first forming groove corresponding to the lower tip of the forming protrusion. The depth of the first forming groove is shallower than that of the second forming groove and the first forming groove is located in the center of the second forming groove. The positioning element is used to fix the fuse body onto the die. The reset component is used to reset the positioning component.

2. The bending fixture according to claim 1, characterized in that, The positioning component and the resetting component are located on the die. The punch moves downward until the forming protrusion is embedded in the second forming groove. The first bending cavity, the positioning component, and the resetting component are pressed down by the punch to a position below the bottom surface of the second forming groove, and the first bending cavity, the positioning component, and the resetting component can move upward to reset.

3. A bending fixture according to claim 2, characterized in that, A support base is provided below the die, and the support base has a clearance space corresponding to the position of the second forming groove. The lower ends of the first bending cavity, positioning part, and resetting part protrude from the die and move up and down within the clearance space.

4. A bending fixture according to claim 3, characterized in that, The support base has a first receiving hole and a second receiving hole at the bottom. The first receiving hole and the second receiving hole are connected to the clearance space at the top and are respectively positioned to correspond to the first bending cavity and the reset component. The first receiving hole and the second receiving hole are respectively provided with a first elastic component and a second elastic component. The first elastic component is connected to the lower end of the first bending cavity for resetting the first bending cavity, and the second elastic component is connected to the lower end of the reset component for resetting the reset component.

5. A bending fixture according to claim 4, characterized in that, The positioning component is fixedly connected to the reset component. The initial position of the reset component is higher than that of the positioning component. The reset component drives the positioning component to be pressed down by the punch. The second elastic component is used to reset the reset component and thus trigger the reset positioning component.

6. A bending fixture according to claim 5, characterized in that, The second forming groove has a through hole that connects to the clearance space and is coaxial with the second receiving hole. The reset member is a column, and the height of the top of the reset member is not lower than the top edge of the second forming groove. The lower end of the reset member passes through the through hole and is located in the clearance space. The positioning member includes a positioning base and two positioning pins on the positioning base. The upper ends of the two positioning pins protrude from the upper surface of the second bending cavity and are located on both sides of the second forming groove. The positioning base is located in the clearance space and is fixedly connected to the reset member. The second elastic member is a spring with its two ends abutting against the second receiving hole and the bottom surface of the positioning base, respectively. The lower end of the first bending cavity is a columnar structure. An abutting platform is protruding between the columnar structure and the first forming groove. The first elastic member is a spring with its two ends abutting against the first receiving hole and the bottom surface of the abutting platform, respectively.

7. A bending fixture according to claim 2, characterized in that, The formed bump is in the shape of an isosceles triangular prism.

8. A bending fixture according to claim 7, characterized in that, The punch is mounted on a support, and a cylinder on the support drives the punch to reciprocate. A limit block is protruding from the rear end of the punch, and a limit crossbar is provided on the support. When the punch descends to the lowest position, the limit crossbar stops the limit block from moving downward.

9. A bending fixture according to claim 2, characterized in that, The die has a weld support plate with the same height on both sides that extends horizontally.

10. A bending fixture according to claim 2, characterized in that, The punch forms upper pressure plates on both sides of the forming protrusion, and the second bending cavity forms lower support plates on both sides of the second forming groove corresponding to the upper pressure plates. When the punch moves downward until the forming protrusion is embedded in the second forming groove, the upper pressure plate presses on the lower support plate.

Images