Powder metallurgy precision pressing dumbbell, vertical punch forming die of powder metallurgy precision pressing dumbbell and using method of vertical punch forming die
Through powder metallurgy technology and vertical stamping molds, the accuracy, environmental protection and energy saving problems of existing cast dumbbells are solved, and high-precision, environmentally friendly and energy-saving finished dumbbell production is achieved.
Patent Information
- Application Number
- CN202411359591.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-27
- Publication Date
- 2025-01-21
AI Technical Summary
The existing steel cast dumbbells have large dimensional accuracy errors, rough surfaces, long production cycles, high costs, and environmental protection and energy saving problems, which are difficult to meet market demand.
Using powder metallurgy technology and vertical stamping molds, through the mold closing and compression of the upper mold, middle mold and lower mold, the finished dumbbell of equal density is precisely pressed, which solves the various defects of existing cast dumbbells.
The high precision, smooth surface, short production cycle, and energy saving and environmental protection of dumbbells have been realized. The accuracy of the accuracy of the cast dumbbell is less than 5 grams/kg.
Smart Images
Figure CN119327080A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a forming and processing technology of powder pressed parts, and in particular to a mold for precisely pressing a bell using powder metallurgy powder and a method for using the mold. Background Art
[0002] With the rapid development of modern science and technology, more and more machines have replaced people's work, people have fewer and fewer opportunities to engage in physical work, and their daily activity time, activity volume and activity intensity are decreasing. The sedentary time using computers, mobile phones and other electronic devices is increasing, and people's health indicators are declining. In the current fast-paced life, high work pressure, and less and less time for exercise, in order to improve people's health, people gradually realize the importance of focusing on fitness exercises. More and more people use fitness exercises to release stress, strengthen their physical fitness, and stay healthy.
[0003] As a simple and effective fitness equipment, dumbbells have been favored by more and more consumers. In recent years, with the rise of the fitness trend, people's demand for fitness equipment has increased year by year, and the dumbbell market has ushered in rapid growth. At present, the finished dumbbells on the market can be divided into the following two types according to their production methods: The first type is a steel dumbbell that is cast as a whole.
[0004] The second type is a steel dumbbell that is cast in parts and then assembled and welded into one. The head and bar of this dumbbell are cast separately, and then undergo precision machining to make the head and bar of the dumbbell reach the pre-designed surface accuracy and dimensional accuracy respectively. Finally, the head and bar are precisely butt-jointed and welded to make the dumbbell as a whole.
[0005] Regardless of the structure of the cast iron dumbbell, there are the following defects: ① The finished iron-shaped steel dumbbells have large dimensional accuracy errors and rough surfaces, and must be machined, ground and polished, which increases energy consumption and causes heavy pollution during the casting process. They are neither energy-saving nor environmentally friendly, have long production cycles and high costs. At present, such products will gradually withdraw from the market.
[0006] ② For the steel casting dumbbell with split assembly structure, although the bell head and the bell rod are cast and processed separately, the defects existing in the castings still exist. At the same time, the two dumbbell heads and a dumbbell rod need to be finely processed before they can be assembled and welded into a whole. Moreover, the processing procedures are more numerous and complicated, and the workload is larger.
[0007] The production of existing cast dumbbells is limited due to policy factors such as environmental protection and energy conservation. At the same time, the accuracy and price of the product also make steel cast dumbbells lose their market competitiveness.
[0008] After a long period of research, the applicant has invented a method for pressing dumbbells with equal density by powder metallurgy, which can ideally solve the problems of existing steel casting dumbbells and their production. It has a simple process, a short production cycle, is energy-saving and environmentally friendly, has high product quality, a smooth surface, high dimensional accuracy, and very little mechanical workload for pressing and forming, thus solving the problems of existing steel casting dumbbell parts. Summary of the invention
[0009] The purpose of the present invention is to provide a forming die for pressing equal-density precision sub-bells by powder metallurgy and a method of using the same, which can press equal-density precision integral sub-bells by powder metallurgy powder at one time.
[0010] The technical solution adopted by the present invention is as follows: A powder metallurgy precision pressed dumbbell comprises a dumbbell head and a dumbbell handle part pressed by powder metallurgy, wherein two dumbbell heads are symmetrically distributed at the two ends of the dumbbell handle part, the two dumbbell heads are regular hexagonal in cross section, and the end faces have arc surfaces, the dumbbell handle part is an arc-shaped rod-shaped body with small ends and a large middle, the axis of the dumbbell handle part is colinear with the center lines of the two dumbbell heads, and the diameter of the dumbbell handle part is smaller than the outer dimensions of the dumbbell head.
[0011] Furthermore, an inlaid connector is provided at the center of the dumbbell head and the dumbbell handle.
[0012] A vertical stamping forming die for precision pressed dumbbells made of powder metallurgy, comprising an upper die component, a middle die plate, a lower die component, an upper ejection driving component, a lower ejection driving component, a mold core on a bell head, a feeder, an operating table and a receiving plate, wherein the upper die component comprises an upper die forming plate, a vertical connecting block, a linkage plate and an upper fixed plate, wherein the upper die forming plate is fixedly connected to the upper fixed plate through two vertical connecting blocks arranged at intervals, the linkage plate is arranged between the upper die forming plate and the upper fixed plate, the mold core on the bell head is fixed on the linkage plate, and a vertical connecting block is arranged between the upper fixed plate and the linkage plate There is an upper demoulding driving component, which drives the bell head upper mold core and the linkage plate combination to perform lifting and lowering actions relative to the upper mold forming plate to meet the requirements of forming and demoulding actions; the lower mold component includes a base, a bell head lower punch, a bell rod lower punch, a forming limit block, an increasing connection block, a lower lifting seat and a lower mold fixing plate, the lower mold fixing plate is fixed to the base through two increasing connection blocks, the two bell head lower punches are fixed to the lower mold fixing plate, the bell rod lower punch is located between the two bell head lower punches and is fixed on the lower lifting seat, and the lower lifting seat is set on the base and The lower lifting seat can be lifted and lowered by the lower ejection driving component and installed on the base between the lower mold fixing plates; the forming limit block is fixed on the base and is located below the lower lifting seat; a through-hole-shaped middle model cavity is provided on the middle template, and the cross-sectional shape of the through-hole-shaped middle model cavity is the same as the cross-sectional shape of the dumbbell finished product on the parting surface, and the through-hole-shaped middle model cavity includes a bell head through hole and a bell rod through hole, and the bell head lower punch and the bell rod lower punch are respectively inserted into the bell head through hole and the bell rod through hole of the middle template, and the upper mold forming plate is arranged above the middle template, and the operating table is fixedly installed on the middle mold The upper end surface of the middle template is flush with the upper surface of the operating table, the feeder is arranged on the upper end surface of the operating table, the feeder can move forward and backward along the upper end surface of the operating table, the feeding port cross-sectional area of the feeder is larger than the upper opening cross-sectional area of the through-hole shaped middle model cavity of the middle template, so as to ensure that the powder in the middle and both ends of the through-hole shaped middle model cavity of the middle template is evenly distributed when feeding; two bell head lower punches are located on the left and right sides of the bell rod lower punch, the two bell head lower punches are fixed on the lower mold fixing plate, and the bell rod lower punch is controlled by the lower demoulding driving component to realize up and down movement.
[0013] Furthermore, a dumbbell upper cavity is provided on the lower end surface of the upper mold forming plate. The dumbbell upper cavity has the same outer dimensions as the upper half of the dumbbell parting surface. The dumbbell upper cavity includes two bell head cavities and one bell handle cavity. The two bell head cavities are symmetrically arranged at both ends of the bell handle cavity. A slot for installing the bell head upper mold core is provided above the bell head cavity.
[0014] Furthermore, the linkage plate is a split assembly structure, including a longitudinal connecting rod and a transverse connecting rod. The two longitudinal connecting rods are distributed left and right, and the two longitudinal connecting rods are parallel to the bell handle cavity in the dumbbell upper cavity on the lower end surface of the upper mold forming plate. The two transverse connecting rods are distributed front and back, and the two ends of the two transverse connecting rods are respectively fixedly connected to the two ends of the two longitudinal connecting rods to form a whole. The cylinder body of the upper ejection driving component is fixed on the upper fixed plate, and the telescopic rod of the upper ejection driving component is connected to the longitudinal connecting rod.
[0015] Furthermore, the longitudinal connecting rod is U-shaped, two transverse connecting rods are fixedly connected to two ends of the longitudinal connecting rod respectively, and the telescopic rod of the upper demoulding driving component is connected to the middle position of the longitudinal connecting rod.
[0016] Furthermore, the lower lifting seat includes a floating bottom plate and two symmetrically distributed connecting ear seats, the two connecting ear seats are fixed on the floating bottom plate, the cylinder body of the lower demoulding driving component is fixed on the base, and the telescopic rod of the lower demoulding driving component is connected to the connecting ear seats.
[0017] Furthermore, the upper demoulding driving component or the lower demoulding driving component is a hydraulic cylinder or a pneumatic telescopic cylinder or an electric telescopic cylinder.
[0018] Method for using the vertical stamping forming die of the powder metallurgy precision pressed dumbbell: Step 1: Add powder; Requirements for powder feeding: The dumbbells to be pressed are divided into dumbbell heads and dumbbell handles. The vertical cross-sections of the two dumbbell heads are regular hexagons, and the end faces of the dumbbell heads have arc surfaces. The dumbbell handles are arc-shaped rods with small ends and a large middle. The axis of the dumbbell handles is collinear with the center lines of the two dumbbell heads. The diameter of the dumbbell handles is smaller than the outer dimensions of the dumbbell heads. According to the structural shape and size requirements of the pressed dumbbell finished product, combined with the compression ratio characteristics of the powder metallurgy powder and the density requirements of the dumbbells to be pressed, the molding compression ratio of the powder metallurgy powder is determined. According to the molding compression ratio, the required powder feeding height in the molding cavity of the dumbbell heads at both ends is calculated as H1, and the height of the dumbbell handles is calculated as H2. The feeding height in the handle forming cavity is H2, two bell head punches and one bell rod punch are inserted in the through-hole shaped middle mold cavity, and the two bell head punches are located on the left and right sides of the bell rod punch, and the two bell head punches are fixed on the lower mold fixing plate, and the bell rod punch is controlled by the lower demoulding driving component to move up and down. When feeding, the middle template floats to the position of the required feeding height H1 of the bell head punch, that is, the distance between the top surface of the middle template and the top surface of the bell head punch is H1, and the upper demoulding driving component works to raise the top surface of the bell rod punch to a distance of H2 from the top surface of the middle template, and the feeder is pushed forward to fill the mold cavity of the middle template with material, and then the feeder retreats to the receiving plate of the operating table; Step 2: Product pressing; Pressing action 1: After the through-hole-shaped middle mold cavity of the middle template is filled with a suitable volume of powder according to the product shape requirements, the upper mold forming plate, the mold core on the bell head, the upper mold drive component and the upper fixed plate move downward synchronously until the upper mold forming plate moves down to contact the upper surface of the middle template; Pressing action 2: After the upper die forming plate is pressed down to the upper surface of the middle die plate, the middle die plate moves downward together with the upper die forming plate. Because the lower die drive component has an overflow function, it drives the bell rod lower punch to move downward after receiving pressure. When the combination of the bell rod lower punch and the lower lifting seat drops to contact the forming limit block, it stops. At this time, the two bell head lower punches and the bell rod lower punch have reached the ultimate position of the final pressing and forming of the product; Step 3: De-mould the finished dumbbell product; Demolding action 1: The finished dumbbell is demolded from the upper mold forming plate: After the finished dumbbell is pressed and formed, the pressure is maintained for a period of time, and the upper mold forming plate is depressurized and moves upward to separate from the middle mold plate. The upper demolding driving component works by moving the mold core on the bell head downward to push the finished dumbbell out of the molding cavity of the upper mold forming plate, and the pressed product is ejected from the upper mold forming plate; Demolding action 2: After the extruded dumbbell product is separated from the upper mold forming plate, the middle mold plate moves downward alone. At this time, the bell head lower punch and the bell bar lower punch remain stationary, and the dumbbell product is completely separated from the middle mold plate; Step 4: Take out the finished pressed dumbbell by hand or by a robot.
[0019] The invention provides a vertical pressing forming die for a powder metallurgy precision pressed dumbbell, through which a dumbbell product can be precisely pressed using powder metallurgy as a raw material, and the die is used in conjunction with a vertical three-platen hydraulic forming machine. The die is designed according to the requirements of the outer dimensions of the finished dumbbell product, and the feeding cavities of the dumbbell head and the dumbbell handle are respectively designed. Powder metallurgy powder is added into the die head cavity and the handle cavity through a feeder, and then a dumbbell product with density and outer shape meeting the requirements can be pressed out through specific mold compression of an upper die component, a middle die component and a lower die component. The die has a simple structure and is convenient and quick to press, thus filling the gap of the lack of powder metallurgy precision pressed dumbbells in China, providing a solution for powder metallurgy pressed precision dumbbells, and solving various defects existing in the existing production of cast dumbbells. The precision dumbbells pressed by powder metallurgy have uniform pressed density, high outer dimension accuracy, good surface quality, and a weight accuracy within 5 g / kg of the accuracy error of cast dumbbells. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 It is a structural schematic diagram of the finished dumbbell to be pressed; Figure 2 This is a schematic diagram of the structure of the vertical stamping die for the powder metallurgy precision pressing of dumbbells in the present invention. Figure 3 for Figure 2 Right view of; Figure 4 for Figure 2 Middle CC section view; Figure 5It is a schematic diagram of the vertical stamping forming die of the powder metallurgy precision pressed dumbbell after the centering template is charged; Figure 6 It is a structural schematic diagram of the upper die component and the middle die plate in the mold closing state in the vertical stamping forming die of the powder metallurgy precision pressing dumbbell; Figure 7 It is a schematic diagram of the structure of the powder metallurgy precision pressed dumbbell during pressing and forming; Figure 8 It is a schematic diagram of the structure of a powder metallurgy precision pressed dumbbell in the upper demoulding state; Fig. 9 It is a schematic diagram of the structure of a powder metallurgy precision pressed dumbbell in the lower demoulding state; Fig.10 It is a structural schematic diagram of the upper mold component; Fig.11 It is the structural schematic diagram of the middle template; Fig.12 It is a three-dimensional structural schematic diagram of the lower mold component; Fig.13 It is a schematic diagram of the split assembly structure of the lower lifting seat in the lower mold component; In the figure: A is the dumbbell head; B is the dumbbell handle; H1 is the feeding height of the bell head forming cavity in the middle template 2, that is, the distance between the top surface of the middle template 2 and the top surface of the bell head lower punch 32; H2 is the feeding height of the bell rod forming cavity, that is, the distance between the top surface of the bell rod lower punch 33 and the top surface of the middle template 2; 1-upper mold component; 2-middle mold plate; 3-lower mold component; 4-upper demoulding driving component; 5-lower demoulding driving component; 6-bell head upper mold core; 7-feeder; 8-operating table; 9-receiving plate; 11-upper mold forming plate; 12-vertical connecting block; 13-linking plate; 131-longitudinal connecting rod; 132-transverse connecting rod; 14-upper fixed plate; 21-through hole-shaped middle mold cavity; 211-bell head through hole; 212-bell rod through hole; 31-base; 32-bell head lower punch; 33-bell rod lower punch; 34-forming limit block; 35-heightening connecting block; 36-lower lifting seat; 361-connecting ear seat; 362-floating bottom plate; 37-lower mold fixing plate. DETAILED DESCRIPTION
[0021] The specific implementation of the present invention is described below in conjunction with the accompanying drawings: Example 1: A powder metallurgy pressed dumbbell, such as Figure 1As shown, it includes a dumbbell head A and a dumbbell handle B pressed by powder metallurgy, the two dumbbell heads A are symmetrically distributed at the two ends of the dumbbell handle B, the two dumbbell heads A are regular hexagonal in cross-section, and the end faces have arc surfaces, the dumbbell handle B is an arc-shaped rod-shaped body with small ends and a large middle, the axis of the dumbbell handle B is colinear with the center line of the two dumbbell heads A, and the diameter of the dumbbell handle B is smaller than the outer dimensions of the dumbbell head A.
[0022] A powder metallurgy dumbbell pressing mold, such as Figure 2-13As shown, it includes an upper mold component 1, a middle mold plate 2, a lower mold component 3, an upper mold drive component 4, a lower mold drive component 5, a bell head mold core 6, a feeder 7, an operating table 8 and a receiving plate 9. The upper mold component 1 includes an upper mold forming plate 11, a vertical connecting block 12, a linkage plate 13 and an upper fixing plate 14. A dumbbell upper cavity 10 is provided on the lower end surface of the upper mold forming plate 11. The dumbbell upper cavity 10 has the same outer dimensions as the upper half of the dumbbell parting surface. The dumbbell upper cavity 10 includes two bell head cavities 101 and a bell handle cavity 102. The two bell head cavities 101 are symmetrically arranged at both ends of the bell handle cavity 102. A slot for installing the bell head upper mold core 6 is provided above the bell head cavity 101. The upper mold forming plate 11 is fixedly connected to the upper fixed plate 14 through two vertical connecting blocks 12 arranged at intervals. The linkage plate 13 is arranged between the upper mold forming plate 11 and the upper fixed plate 14. The bell head mold core 6 is fixed on the linkage plate 13. An upper demoulding driving component 4 is provided between the upper fixed plate 14 and the linkage plate 13. The upper demoulding driving component 4 drives the bell head mold core 6 and the linkage plate 13 to move. The combination body performs lifting and lowering actions relative to the upper mold forming plate 11 to meet the requirements of molding and demoulding actions; the lower mold component 3 includes a base 31, a bell head lower punch 32, a bell rod lower punch 33, a molding limit block 34, an increased connection block 35, a lower lifting seat 36 and a lower mold fixing plate 37, the lower mold fixing plate 37 is fixed to the base 31 through two increased connection blocks 35, the two bell head lower punches 32 are fixed to the lower mold fixing plate 37, the bell rod lower punch 33 is located between the two bell head lower punches 32, and is fixed on the lower lifting seat 36, the lower lifting seat 36 is arranged between the base 31 and the lower mold fixing plate 37, and the lower lifting seat 36 can be lifted and installed on the base 31 through the lower demoulding driving component 5; the molding limit block 34 is fixed to the base 31 and is located below the lower lifting seat 36; A through-hole-shaped middle model cavity 21 is provided on the middle template 2. The cross-sectional shape of the through-hole-shaped middle model cavity 21 is the same as the cross-sectional shape of the dumbbell finished product at the parting surface. The through-hole-shaped middle model cavity 21 includes a bell head through hole 211 and a bell rod through hole 212. The bell head lower punch 32 and the bell rod lower punch 33 are respectively inserted into the bell head through hole 211 and the bell rod through hole 212 of the middle template 2. The upper mold forming plate 11 is arranged above the middle template 2. The operating table 8 is fixedly installed on the middle template 2. The upper end surface of the middle template 2 is flush with the upper surface of the operating table 8. The feeder 7 is arranged on the upper end surface of the operating table 8, and the feeder 7 can move forward and backward along the upper end surface of the operating table 8. The cross-sectional area of the feeding port of the feeder 7 is larger than the upper opening cross-sectional area of the through-hole-shaped middle model cavity 21 of the middle template 2, so as to ensure that the powder in the middle and at both ends of the through-hole-shaped middle model cavity 21 of the middle template 2 is evenly distributed when feeding; two bell head lower punches 32 are located on the left and right sides of the bell rod lower punch 33, and the two bell head lower punches 32 are fixed on the lower mold fixing plate 37, and the bell rod lower punch 33 is controlled by the lower demoulding driving component 5 to realize up and down movement.
[0023] In this example, the linkage plate 13 is a split assembly structure, including a longitudinal connecting rod 131 and a transverse connecting rod 132. The two longitudinal connecting rods 131 are distributed left and right, and the two longitudinal connecting rods 131 are parallel to the handle in the dumbbell upper cavity 10 on the lower end surface of the upper mold forming plate 11. The two transverse connecting rods 132 are distributed front and back, and the two ends of the two transverse connecting rods 132 are respectively fixedly connected to the two ends of the two longitudinal connecting rods 131 to form a whole. The cylinder body of the upper demolding driving component 4 is fixed on the upper fixed plate 14. The longitudinal connecting rod 131 is U-shaped, and the two transverse connecting rods 132 are respectively fixedly connected to the two ends of the longitudinal connecting rod 131. The telescopic rod of the upper demolding driving component 4 is connected to the middle position of the longitudinal connecting rod 131.
[0024] The lower lifting seat 36 includes a floating bottom plate 361 and two symmetrically distributed connecting ear seats 362, the two connecting ear seats 362 are fixed on the floating bottom plate 361, the cylinder body of the lower demoulding driving component 5 is fixed on the base 31, and the telescopic rod of the lower demoulding driving component 5 is connected to the connecting ear seats 362.
[0025] The upper demoulding driving component 4 and the lower demoulding driving component 5 are both hydraulic cylinders or pneumatic telescopic cylinders or telescopic electric cylinders.
[0026] Method for using this powder metallurgy dumbbell pressing mold: Step 1: Add powder; Requirements for powder feeding: The dumbbells to be pressed are divided into dumbbell heads A and dumbbell handles B. The vertical cross-section of the two dumbbell heads A is a regular hexagon, and the end face of the dumbbell heads A has an arc surface. The dumbbell handles B are small at both ends and large in the middle. The axis of the dumbbell handles B is collinear with the center lines of the two dumbbell heads A. The diameter of the dumbbell handles B is smaller than the outer dimensions of the dumbbell heads A. According to the structural shape and size requirements of the pressed dumbbell finished product, combined with the compression ratio characteristics of the powder metallurgy powder and the density requirements of the dumbbells to be pressed, the molding compression ratio of the powder metallurgy powder is determined. In this case, it is 2:1. According to the molding compression ratio, the molding compression ratios of the dumbbell heads A at both ends are calculated respectively. The required powder feeding height in the cavity is H1, and the feeding height in the forming cavity of the dumbbell handle part B is H2. Two bell head lower punches 32 and one bell rod lower punch 33 are inserted into the through-hole-shaped middle model cavity 21, and the two bell head lower punches 32 are located on the left and right sides of the bell rod lower punch 33. The two bell head lower punches 32 are fixed on the lower mold fixing plate 37, and the bell rod lower punch 33 is controlled by the lower mold drive component 5 to move up and down. When feeding, the middle template 2 floats to the position of the required feeding height H1 of the bell head lower punch 32, that is, the distance between the top surface of the middle template 2 and the top surface of the bell head lower punch 32 is H1, and the upper mold drive component 4 works to raise the top surface of the bell rod lower punch 33 to a distance of H2 from the top surface of the middle template 2, and the feeder 7 is pushed forward to fill the mold cavity of the middle template 2 with material, and then the feeder 7 retreats to the receiving plate 9 of the operating table; Step 2: Product pressing; Pressing action 1: After the through-hole-shaped middle mold cavity 21 of the middle mold plate 2 is filled with a suitable volume of powder according to the product shape requirements, the upper mold forming plate 11, the bell head mold core 6, the upper mold drive component 4 and the upper fixed plate 14 move downward synchronously until the upper mold forming plate 11 moves downward to contact the upper surface of the middle mold plate 2; Pressing action 2: After the upper die forming plate 11 is pressed down onto the upper surface of the middle die plate 2, the middle die plate 2 moves downward together with the upper die forming plate 11. Since the lower ejection driving component 5 has an overflow function, it drives the bell rod lower punch 33 to move downward after receiving pressure. The combination of the bell rod lower punch 33 and the lower lifting seat 36 stops when it falls to contact with the forming limit block 34. At this time, the two bell head lower punches 32 and the bell rod lower punch 33 have reached the ultimate position of the final pressing and forming of the product. Step 3: De-mould the finished dumbbell product; Demolding action 1: The finished dumbbell is demolded from the upper mold forming plate 11: After the finished dumbbell is pressed and formed, the pressure is maintained for a period of time, and the upper mold forming plate 11 is depressurized and moves upward to separate from the middle mold plate 2, and the upper demolding driving component 4 works to push the finished dumbbell out of the upper cavity 10 of the upper mold forming plate 11 through the lower mold core 6 on the bell head, and the pressed product is ejected from the upper cavity 10 in the upper mold forming plate 11; Demolding action 2: After the extruded dumbbell product is separated from the upper mold forming plate 11, the middle mold plate 2 moves downward alone. At this time, the bell head lower punch 32 and the bell bar lower punch 33 remain stationary. When the middle mold plate 2 moves down to the limit position, the dumbbell product is completely separated from the middle mold plate 2; Step 4: Take out the finished pressed dumbbell by hand or by a robot.
[0027] The invention provides a vertical pressing forming die for a precision pressed dumbbell made of powder metallurgy, through which a precision pressed dumbbell product can be made using powder metallurgy as a raw material, and the die is used in conjunction with a vertical hydraulic forming machine. The die is designed according to the requirements of the outer dimensions of the finished dumbbell product, and the feeding cavities of the dumbbell head and the dumbbell handle are respectively designed. Powder metallurgy powder is added into the die head cavity and the handle cavity through a feeder, and then a dumbbell product with density and outer shape meeting the requirements can be pressed out through specific mold compression of an upper die component, a middle die component and a lower die component. The die has a simple structure, and the pressing is convenient and fast, filling the gap that there is no precision pressed dumbbell made of powder metallurgy in China, providing a solution for pressing precision dumbbells made of powder metallurgy, and solving various defects existing in the existing production of cast dumbbells. The precision dumbbells pressed by powder metallurgy have uniform pressing density, high outer dimension accuracy, good surface quality, and a weight accuracy within 5 g / kg of the accuracy error of the cast dumbbell.
[0028] The above are only preferred implementation modes of the present invention. The protection scope of the present invention is not limited to the above embodiments. For ordinary technicians in this technical field, all technical solutions with equivalent functional substitutions proposed without departing from the principles of the present invention belong to the protection scope of the present invention.
Claims
1. A powder metallurgy precision pressed dumbbell, characterized by: The dumbbell comprises a dumbbell head (A) and a dumbbell handle (B) pressed by powder metallurgy. The two dumbbell heads (A) are symmetrically distributed at the two ends of the dumbbell handle (B). The two dumbbell heads (A) are regular hexagonal in cross-section, and the end faces have arc surfaces. The dumbbell handle (B) is an arc-shaped rod-shaped body with small ends and a large middle. The axis of the dumbbell handle (B) is colinear with the center line of the two dumbbell heads (A). The diameter of the dumbbell handle (B) is smaller than the outer dimensions of the dumbbell head (A).
2. A powder metallurgy precision pressed dumbbell according to claim 1, characterized in that: An inlay connector is provided at the center of the dumbbell head (A) and the dumbbell handle (B).
3. A vertical stamping die for precision pressed dumbbells made of powder metallurgy, characterized by: The invention comprises an upper mold component (1), a middle mold plate (2), a lower mold component (3), an upper mold ejection driving component (4), a lower mold ejection driving component (5), a bell head upper mold core (6), a feeder (7), an operating table (8) and a material receiving plate (9), wherein the upper mold component (1) comprises an upper mold forming plate (11), a vertical connecting block (12), a linkage plate (13) and an upper fixing plate (14). The upper mold forming plate (11) is fixedly connected to the upper fixed plate (14) through two vertical connecting blocks (12) arranged at intervals. The linkage plate (13) is arranged between the upper mold forming plate (11) and the upper fixed plate (14). The mold core (6) on the bell head is fixed on the linkage plate (13). An upper demoulding driving component (4) is arranged between the upper fixed plate 11 and the linkage plate (13). The upper demoulding driving component (4) drives the combination of the mold core (6) on the bell head and the linkage plate (13) to move up and down relative to the upper mold forming plate (11) to meet the requirements of molding and demoulding actions. The lower mold component (3) includes a base (31), a bell head lower punch (32), and a bell rod lower punch (33). The lower die fixing plate (37) is fixed to the base (31) through two height-increasing connecting blocks (35); the two bell head lower punches (32) are fixed to the lower die fixing plate (37); the bell rod lower punch (33) is located between the two bell head lower punches (32) and is fixed to the lower lifting seat (36); the lower lifting seat (36) is arranged between the base (31) and the lower die fixing plate (37); the lower lifting seat (36) can be lifted and lowered on the base (31) through a lower ejection driving component (5); the forming limit block (34) is ... bell rod lower punch (33) is located between the two bell head lower punches (32) and is fixed to the lower lifting seat (36); the bell rod lower punch (33) is located between the two bell head lower punches (32) and is fixed to the lower lifting seat (36); the bell rod lower punch (33) is located between the two bell head lower punches (32) and is fixed to the lower lifting seat (36); the bell rod lower punch (33) is located between the two bell head lower punches (32) and is fixed to the lower lifting seat (36); the bell rod lower punch (33) is located between the base (31) and the lower die fixing plate (37); the bell rod lower punch (33) is located between the base (31) and the lower die fixing plate (37); The base (31) is disposed on the middle template (2) and is located below the lower lifting seat (36); a through-hole middle model cavity (21) is provided on the middle template (2); the cross-sectional shape of the through-hole middle model cavity (21) is the same as the cross-sectional shape of the dumbbell finished product at the parting surface; the through-hole middle model cavity (21) comprises a bell head through hole (211) and a bell rod through hole (212); a bell head lower punch (32) and a bell rod lower punch (33) are respectively inserted into the bell head through hole (211) and the bell rod through hole (212) of the middle template (2); an upper mold forming plate (11) is arranged above the middle template (2); an operating table (8) is fixedly installed on the middle template (2); and an upper end surface of the middle template (2) is in contact with the operating table (8). The upper surface of the operating table (8) is flush, the feeder (7) is arranged on the upper end surface of the operating table (8), the feeder (7) can move forward and backward along the upper end surface of the operating table (8), the feeding port cross-sectional area of the feeder (7) is larger than the upper opening cross-sectional area of the through-hole-shaped middle mold cavity (21) of the middle template (2), so as to ensure that the powder material in the middle and both ends of the through-hole-shaped middle mold cavity (21) of the middle template (2) is evenly distributed when feeding; two bell head lower punches (32) are located on the left and right sides of the bell rod lower punch (33), the two bell head lower punches (32) are fixed on the lower mold fixing plate (37), and the bell rod lower punch (33) is controlled by the lower mold ejection driving component (5) to realize the up and down movement.
4. The vertical stamping forming die for the powder metallurgy precision pressed dumbbell according to claim 3 is characterized in that: A dumbbell upper cavity (10) is provided on the lower end surface of the upper mold forming plate (11). The dumbbell upper cavity (10) has the same outer dimensions as the upper half of the dumbbell parting surface. The dumbbell upper cavity (10) comprises two bell head cavities (101) and a bell handle cavity (102). The two bell head cavities (101) are symmetrically arranged at two ends of the bell handle cavity (102). A slot for mounting a bell head upper mold core (6) is provided above the bell head cavity (101).
5. The vertical stamping forming die for powder metallurgy precision pressed dumbbells according to claim 3 is characterized by: The linkage plate (13) is a split assembly structure, comprising a longitudinal connecting rod (131) and a transverse connecting rod (132), the two longitudinal connecting rods (131) being distributed left and right, the two longitudinal connecting rods (131) being parallel to the bell handle cavity (102) in the dumbbell upper cavity (10) on the lower end surface of the upper mold forming plate (11), the two transverse connecting rods (132) being distributed front and back, the two ends of the two transverse connecting rods (132) being respectively fixedly connected to the two ends of the two longitudinal connecting rods (131) to form an integral body, the cylinder body of the upper ejection driving component (4) being fixed on the upper fixed plate (14), and the telescopic rod of the upper ejection driving component (4) being connected to the longitudinal connecting rod (131).
6. The vertical stamping forming die for powder metallurgy precision pressed dumbbells according to claim 5, characterized in that: The longitudinal connecting rod (131) is U-shaped, and two transverse connecting rods (132) are respectively fixedly connected to two ends of the longitudinal connecting rod (131), and the telescopic rod of the upper demoulding driving component (4) is connected to the middle position of the longitudinal connecting rod (131).
7. The vertical stamping forming die for powder metallurgy precision pressed dumbbells according to claim 3 is characterized by: The lower lifting seat (36) comprises a floating bottom plate (361) and two symmetrically distributed connecting ear seats (362), the two connecting ear seats (362) are fixed on the floating bottom plate (361), the cylinder body of the lower demoulding driving component (5) is fixed on the base (31), and the telescopic rod of the lower demoulding driving component (5) is connected to the connecting ear seats (362).
8. The vertical stamping forming die for powder metallurgy precision pressed dumbbells according to claim 3 is characterized by: The upper demoulding drive component (4) or the lower demoulding drive component (5) is a hydraulic cylinder or a pneumatic telescopic cylinder or an electric telescopic cylinder.
9. The method for using the vertical stamping forming die of the powder metallurgy precision pressed dumbbell according to claim 3: Step 1: Add powder; Requirements for powder feeding: The dumbbells to be pressed are divided into dumbbell heads (A) and dumbbell handles (B). The vertical cross-section of the two dumbbell heads (A) is a regular hexagon. The end faces of the dumbbell heads (A) have arc surfaces. The dumbbell handles (B) are arc-shaped rods with small ends and a large middle. The axis of the dumbbell handles (B) is collinear with the center lines of the two dumbbell heads (A). The diameter of the dumbbell handles (B) is smaller than the outer dimensions of the dumbbell heads (A). According to the structural shape and size requirements of the pressed dumbbells, combined with the compression ratio characteristics of the powder metallurgy powders and the density requirements of the dumbbells to be pressed, the molding compression ratio of the powder metallurgy powders is determined. According to the molding compression ratio, the required powder feeding height in the molding cavity of the dumbbell heads (A) at both ends is calculated as H1, and the feeding height in the molding cavity of the dumbbell handles (B) is calculated as H2. A head punch (32) and a bell rod punch (33) are inserted into a through-hole-shaped middle mold cavity (21), and the two bell head punches (32) are located on the left and right sides of the bell rod punch (33). The two bell head punches (32) are fixed on a lower mold fixing plate (37). The bell rod punch (33) is controlled by a lower mold ejection driving component (5) to move up and down. When feeding, the middle mold plate (2) floats to a position of a required feeding height H1 of the bell head punch (32), that is, the distance between the top surface of the middle mold plate (2) and the top surface of the bell head punch (32) is H1. The upper mold ejection driving component (4) works to raise the top surface of the bell rod punch (33) to a distance H2 from the top surface of the middle mold plate (2). The feeder (7) is pushed forward to fill the mold cavity of the middle mold plate (2) with material, and then the feeder (7) retreats to a receiving plate (9) on an operating table. Step 2: Product pressing; Pressing action 1: After the through-hole-shaped middle mold cavity (21) of the middle mold plate (2) is filled with a suitable volume of powder according to the product shape requirements, the upper mold forming plate (11), the bell head mold core (6), the upper mold ejection driving component (4) and the upper fixed plate (14) move downward synchronously until the upper mold forming plate (11) moves downward to contact the upper surface of the middle mold plate (2); Pressing action 2: After the upper die forming plate (11) is pressed down onto the upper surface of the middle die plate (2), the middle die plate (2) moves downward together with the upper die forming plate (11). Since the lower ejection driving component (5) has an overflow function, it drives the bell rod lower punch (33) to move downward after receiving pressure. The bell rod lower punch (33) and the lower lifting seat (36) stop when the combination of the bell rod lower punch (33) and the lower lifting seat (36) is lowered to contact the forming limit block (34). At this time, the two bell head lower punches (32) and the bell rod lower punch (33) have reached the ultimate position of the final pressing and forming of the product. Step 3: De-mould the finished dumbbell product; Demolding action 1: the dumbbell finished product is demolded from the upper mold forming plate (11): after the dumbbell finished product is pressed and formed, the pressure is maintained for a period of time, the upper mold forming plate (11) is depressurized and moves upward to separate from the middle mold plate (2), and the upper demolding driving component (4) works to move the upper mold core (6) of the bell head downward to eject the dumbbell finished product from the molding cavity of the upper mold forming plate (11), and the pressed product is ejected from the upper mold forming plate (11); Demolding action 2: After the extruded dumbbell product is separated from the upper mold forming plate (11), the middle mold plate (2) moves downward alone, at which time, the bell head lower punch (32) and the bell bar lower punch (33) remain stationary, and the dumbbell product is completely separated from the middle mold plate (2); Step 4: Take out the finished pressed dumbbell by hand or by a robot.