Mechanical self-tightening device based on novel punch and working method of mechanical self-tightening device

Abstract

The mechanical self-tightening device comprises a base, a plurality of vertically-extending guide columns are arranged on the base in an array mode, the tops of the guide columns penetrate through a fixing plate and are fixedly connected with the fixing plate, a hydraulic cylinder is fixedly arranged on the fixing plate, and the bottom of the telescopic end of the hydraulic cylinder is coaxially connected with the punch. An interference head with the diameter larger than that of the punch is fixedly arranged at the bottom end of the punch, a conical head facilitating stretching in is fixedly arranged at the bottom of the interference head, two clamping blocks which are in sliding connection with the base and used for oppositely sliding to clamp and fix a barrel are symmetrically arranged on the base, and the mechanical self-tightening device based on the novel punch is simple in structure, low in machining cost and convenient and fast to maintain.

Description

Technical Field

[0001] The invention relates to a mechanical self-tightening device based on a novel punch and a working method thereof. Background Art

[0002] Mechanical self-tightening is also called extrusion self-tightening, which is to use hydraulic pressure or a push rod to force a punch slightly larger than the inner diameter of the barrel to expand the barrel. The punch has an important influence on mechanical self-tightening, and the traditional punch shape is a double-conical cylinder with small ends and a large middle, made of specially treated high-performance high-speed steel or tungsten carbide hard alloy through isostatic pressing.

[0003] In the material selection of mechanical self-tightening punches, the commonly used tungsten carbide material has some performance and use problems. First, tungsten carbide has extremely high hardness and wear resistance, but its toughness is relatively low. In the stamping of high-hardness materials, if encountering a large impact force or complex stress conditions, the tungsten carbide punch may suffer from brittle fracture, affecting the continuity of the stamping work. Secondly, tungsten carbide materials are difficult to process and require special processing technology and equipment. This not only increases the manufacturing cost, but may also lead to an extension of the punch manufacturing cycle and affect the production schedule. In addition, the price of tungsten carbide materials themselves is relatively high, and the increased manufacturing cost caused by the difficulty of processing makes the overall cost of tungsten carbide punches higher than other materials.

[0004] In addition, in mechanical self-tightening devices, the traditional double-cone cylindrical punches commonly used often have some problems and defects. Due to its shape, the traditional double-cone cylindrical punch often uses a push rod to push the punch to achieve the purpose of extrusion and expansion, but it is not suitable for some work scenarios where the punch needs to be pulled out. In the manufacturing process, due to the complexity of its shape, the processing difficulty is relatively large, and it is difficult to ensure high precision. This may cause the punch to not fit tightly enough with the die, deviations during stamping, affecting the quality of the stamped parts, and there may be problems with insufficient strength in the design. In addition, due to the high pressure and high frequency of the stamping environment, the punch is prone to deformation or even fracture, affecting the continuity and stability of the stamping work. At the same time, due to its high processing difficulty and relatively high manufacturing cost, once the double-cone cylindrical punch is worn or damaged, it is relatively difficult to repair, which is very unfavorable for the scale, continuity and economy of production.

[0005] In summary, the tungsten carbide material commonly used in traditional double-conical cylinders has low toughness and is prone to brittle fracture, poor economic performance, and the punch shape has problems such as high processing difficulty, low precision, high manufacturing cost, and difficulty in maintenance. Therefore, the research on mechanical self-tightening device based on new punch has important research and application value. Summary of the invention

[0006] In view of the deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a mechanical self-tightening device based on a new punch and a working method thereof, which is not only reasonable in structure but also simple in operation and has low maintenance cost.

[0007] In order to solve the above technical problems, the technical solution of the present invention is: a mechanical self-tightening device based on a new type of punch, comprising a base, a plurality of vertically extending guide columns are arranged in an array on the base, the tops of the guide columns all penetrate the fixed plate and are fixedly connected to the fixed plate, a hydraulic cylinder is fixedly provided on the fixed plate, a punch is coaxially connected to the bottom of the telescopic end of the hydraulic cylinder, an interference head with a diameter larger than the punch is fixedly provided at the bottom of the interference head, a conical head is fixedly provided at the bottom of the interference head to facilitate insertion, and two clamping blocks that are symmetrically provided on the base and are slidably connected to the base and are used to slide towards each other to clamp the barrel.

[0008] Furthermore, arc grooves are provided inwardly on opposite sides of the two clamping blocks for adhering to the outer wall of the barrel for clamping, and the arc grooves pass through the clamping blocks vertically.

[0009] Furthermore, the outer sides of the clamping blocks can be detachably connected to the push seat, and the outer side of the push seat is driven by a clamping hydraulic cylinder to extend and retract horizontally.

[0010] Furthermore, a guide seat is fixedly provided between the push seat and the driving end of the clamping hydraulic cylinder, and both ends of the guide seat are fixedly connected with guide rods extending parallel to the telescopic direction of the clamping hydraulic cylinder, and the ends of the guide rods are slidably mounted on the mounting seat outside the clamping hydraulic cylinder.

[0011] Furthermore, the mounting seat sleeve is arranged outside the clamping hydraulic cylinder body and the bottom is fixedly connected to the extension seat on the side of the base.

[0012] Furthermore, the clamping block is provided with threaded holes on the outer side of the arc groove, and fixing bolts are screwed into the threaded holes; a plurality of fixing grooves with inverted convex cross-sections are provided at intervals above and below the push seat, the fixing grooves penetrate the push seat longitudinally and the convex ends extend toward the clamping block side, a positioning block is provided in the fixing groove and is connected to the fixing bolts through the positioning block to position the clamping block.

[0013] Furthermore, the punch is fixedly connected to the hydraulic cylinder via a guide plate, the upper end of the guide plate is fixedly connected to the telescopic end of the hydraulic cylinder, and the lower end is fixedly provided with an upper clamp, which is sleeved on the upper end of the punch and tightened by an adjusting bolt that is radially screwed in from the outside to the inside.

[0014] Furthermore, the guide plate is provided with a guide hole for the guide column to pass through for vertical guiding sliding.

[0015] Furthermore, a support platform is fixedly provided in the middle of the base, and an inner core is provided on the support platform for being coaxially cushioned in the barrel.

[0016] A working method of a mechanical self-tightening device based on a new type of punch is carried out in the following steps: first, fix the barrel, place the inner core on a support table, and vertically insert the barrel to the inner core, fix the clamp on the push seat by a fixing bolt, then drive two clamping hydraulic cylinders to push the two clamps toward each other and move them horizontally outside the barrel, then install the punch, insert the top of the punch into the upper clamp and tighten it with an adjusting bolt, finally drive the hydraulic cylinder to drive the punch downward, the conical head first extends into the barrel for guide buffering, and the interference fit between the interference head and the inner wall of the barrel is realized to achieve the purpose of mechanical self-tightening, when the predetermined stamping depth is reached, the hydraulic cylinder stops working and moves in the opposite direction, driving the punch to reset upward; then the clamping hydraulic cylinder is reset to take out the processed workpiece and prepare for the next stamping operation.

[0017] Compared with the prior art, the present invention has the following beneficial effects: the mechanical self-tightening device based on the new punch has a simple structure and low processing cost, and solves the problem that the tungsten carbide material commonly used in traditional punches has low toughness and is prone to brittle fracture, and is replaced with DC53 mold steel; and in view of the problems of difficulty in punch shape processing, insufficient precision, and difficulty in maintenance, a "three-stage composite structure" punch structure is designed, while reducing the cost of punch production and maintenance.

[0018] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the structure of an embodiment of the present invention; Figure 2 Schematic diagram of the structure of the punch in the embodiment of the present invention; Figure 3 A top view of an embodiment of the present invention; Figure 4 Schematic diagram of the cooperation between the clamp block and the barrel in an embodiment of the present invention.

[0020] In the figure: 1-base, 2-guide column, 3-hydraulic cylinder, 4-punch, 5-interference head, 6-conical head, 7-clamping block, 8-arc groove, 9-clamping hydraulic cylinder, 10-guide seat, 11-guide rod, 12-extension seat, 13-threaded hole, 14-fixing bolt, 15-fixing groove, 16-positioning block, 17-guide plate, 18-upper clamp, 19-adjusting bolt, 20-guide hole, 21-support table, 22-inner core, 23-barrel, 24-drive switch, 25-fixing plate, 26-mounting seat, 27-sliding hole, 28-push seat. DETAILED DESCRIPTION

[0021] In order to make the above features and advantages of the present invention more clearly understood, embodiments are given below with reference to the accompanying drawings for detailed description.

[0022] like Figures 1 to 4 As shown, a mechanical self-tightening device based on a novel punch comprises a base 1, on which a plurality of vertically extending guide columns 2 are arranged in an array, the tops of the guide columns all penetrate a fixed plate 5 and are fixedly connected thereto, a hydraulic cylinder 3 is fixedly arranged on the fixed plate, a punch 4 is coaxially connected to the bottom of the telescopic end of the hydraulic cylinder, an interference head 5 having a diameter larger than that of the punch is fixedly arranged at the bottom of the punch, a conical head 6 for facilitating insertion into the barrel is fixedly arranged at the bottom of the interference head, the conical head is coaxially arranged with the interference head and the punch, and the conical head is in a frustum shape with the tip facing downward, two clamping blocks 7 symmetrically arranged on the base which are slidably connected to the base and are used for sliding towards each other to clamp the barrel 23, and the punch, the interference head and the conical head are all made of DC53 die steel.

[0023] In the embodiment of the present invention, the opposite sides of the two clamping blocks are both provided with arc grooves 8 facing inwards for adhering to the outer wall of the barrel for clamping. The arrangement of the arc grooves can adapt to the clamping of barrels of different sizes within a certain range, and the arc grooves pass through the clamping blocks from top to bottom.

[0024] In the embodiment of the present invention, the outer side of the clamp block can be detachably connected to the push seat 28, and the outer side of the push seat is driven by the clamping hydraulic cylinder 9 to extend and retract horizontally.

[0025] In the embodiment of the present invention, a guide seat 10 is fixedly provided between the push seat and the driving end of the clamping hydraulic cylinder, and both ends of the guide seat are fixedly connected with guide rods 11 extending parallel to the telescopic direction of the clamping hydraulic cylinder. The ends of the guide rods are slidably mounted on a mounting seat 26 outside the clamping hydraulic cylinder, and a sliding hole 27 is provided on the mounting seat for the guide rod to pass through.

[0026] In the embodiment of the present invention, the mounting seat is arranged outside the clamping hydraulic cylinder body and the bottom is fixedly connected to the extension seat 12 on the side of the base, the lateral extension end of the extension seat is fixedly connected to the base, and a driving switch 24 for opening and closing the hydraulic cylinder and the clamping hydraulic cylinder is fixedly arranged on the extension seat.

[0027] In the embodiment of the present invention, threaded holes 13 are formed through the outer side of the arc groove on the clamping block, and fixing bolts 14 are screwed into the threaded holes; a plurality of fixing grooves 15 with inverted convex cross-sections are formed at intervals up and down on the push seat, the fixing grooves penetrate the push seat longitudinally and the convex ends extend toward the clamping block side, a positioning block 16 is provided in the fixing groove and is connected to the fixing bolts through the positioning block to position the clamping block.

[0028] In the embodiment of the present invention, the punch is fixedly connected to the hydraulic cylinder via a guide plate 17, the upper end of the guide plate is fixedly connected to the telescopic end of the hydraulic cylinder, and the lower end is fixedly provided with an upper clamp 18, which is sleeved on the upper end of the punch and fastened by an adjusting bolt 19 which is radially screwed in from the outside to the inside.

[0029] In the embodiment of the present invention, the guide plate is provided with a guide hole 20 for the guide column to pass through for vertical guiding sliding.

[0030] In the embodiment of the present invention, a support platform 21 is fixedly provided in the middle of the base, and an inner core 22 is provided on the support platform for coaxial padding in the barrel.

[0031] A working method of a mechanical self-tightening device based on a new type of punch is carried out in the following steps: first, a barrel is fixed, an inner core is placed on a support table, and the barrel is vertically inserted to the inner core, a clamp block is fixed on a push seat by a fixing bolt, and then two clamp blocks are driven toward each other by driving two clamping hydraulic cylinders to be horizontally clamped outside the barrel, and then the punch is installed, the top of the punch is inserted into an upper clamping tube and tightened and fixed by adjusting bolts, and finally the hydraulic cylinder is driven to work and drive the punch downward, the conical head first extends into the barrel for guiding and buffering, and the interference fit between the interference head and the inner wall of the barrel is realized to achieve the purpose of mechanical self-tightening, and when a predetermined stamping depth is reached, the hydraulic cylinder stops working and moves in the opposite direction, driving the punch to reset upward; after that, the clamping hydraulic cylinder is reset to take out the processed workpiece and prepare for the next stamping operation.

[0032] The present invention is not limited to the above-mentioned best implementation mode. Anyone can derive other various forms of mechanical self-tightening devices based on new punches and working methods thereof under the enlightenment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

Claims

1. A mechanical self-tightening device based on a new punch, characterized in that: It comprises a base, on which a plurality of vertically extending guide columns are arranged in an array, the tops of the guide columns all penetrate through a fixed plate and are fixedly connected thereto, a hydraulic cylinder is fixedly arranged on the fixed plate, a punch is coaxially connected to the bottom of the telescopic end of the hydraulic cylinder, an interference head with a diameter larger than that of the punch is fixedly arranged at the bottom of the interference head, a conical head is fixedly arranged at the bottom of the interference head for easy insertion, and two clamping blocks which are symmetrically arranged on the base and are slidably connected to the base and are used for sliding towards each other to clamp the barrel.

2. According to claim 1, a mechanical self-tightening device based on a new punch is characterized in that: The opposite sides of the two clamping blocks are both concavely provided with arc grooves for adhering to the outer wall of the barrel for clamping, and the arc grooves pass through the clamping blocks vertically.

3. A mechanical self-tightening device based on a novel punch according to claim 2, characterized in that: The outer sides of the clamping blocks can be detachably connected to the push seat, and the outer side of the push seat is driven by a clamping hydraulic cylinder to extend and retract horizontally.

4. A mechanical self-tightening device based on a novel punch according to claim 3, characterized in that: A guide seat is fixedly arranged between the push seat and the driving end of the clamping hydraulic cylinder. Both ends of the guide seat are fixedly connected with guide rods extending parallel to the telescopic direction of the clamping hydraulic cylinder. The ends of the guide rods are slidably mounted on the mounting seat outside the clamping hydraulic cylinder.

5. A mechanical self-tightening device based on a novel punch according to claim 4, characterized in that: The mounting seat sleeve is arranged outside the clamping hydraulic cylinder body and the bottom is fixedly connected to the extension seat on the side of the base.

6. A mechanical self-tightening device based on a novel punch according to claim 3, characterized in that: The clamp block is provided with threaded holes on the outer side of the arc groove, and fixing bolts are screwed into the threaded holes; the push seat is provided with a plurality of fixing grooves with inverted convex cross-sections at intervals up and down, the fixing grooves penetrate the push seat longitudinally and the convex ends extend toward the clamp block side, a positioning block is provided in the fixing groove and is connected to the fixing bolts through the positioning block to position the clamp block.

7. A mechanical self-tightening device based on a novel punch according to claim 1, characterized in that: The punch is fixedly connected to the hydraulic cylinder via a guide plate, the upper end of the guide plate is fixedly connected to the telescopic end of the hydraulic cylinder, and the lower end is fixedly provided with an upper clamping sleeve, which is sleeved on the upper end of the punch and tightened by an adjusting bolt that is radially screwed in from the outside to the inside.

8. The mechanical self-tightening device based on the novel punch according to claim 1 is characterized in that: The guide plate is provided with a guide hole for the guide column to pass through for vertical guiding sliding.

9. A mechanical self-tightening device based on a novel punch according to claim 1, characterized in that: A support platform is fixedly arranged in the middle of the base, and an inner core coaxially cushioned in the barrel is arranged on the support platform.

10. A working method of a mechanical self-tightening device based on a new punch, characterized in that: A mechanical self-tightening device based on a new punch as described in any one of claims 1 to 9 is adopted, and the following steps are followed: first, the barrel is fixed, an inner core is placed on a support platform, and the barrel is vertically inserted to the inner core, and the clamp is fixed to the push seat by a fixing bolt, and then the two clamps are driven toward each other by the two clamping hydraulic cylinders to move the two clamps horizontally outside the barrel, and then the punch is installed, the top of the punch is inserted into the upper clamp and tightened and fixed by the adjusting bolt, and finally the hydraulic cylinder is driven to work and drive the punch downward, and the conical head first extends into the barrel guide buffer, and the interference fit between the interference head and the inner wall of the barrel is realized to achieve the purpose of mechanical self-tightening. When the predetermined stamping depth is reached, the hydraulic cylinder stops working and moves in the opposite direction, driving the punch to reset upward; after that, the clamping hydraulic cylinder is reset to take out the processed workpiece and prepare for the next stamping operation.

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