CN111940741A - Powder metallurgy brake pad friction block shaping die and method - Google Patents
Powder metallurgy brake pad friction block shaping die and method Download PDFInfo
- Publication number
- CN111940741A CN111940741A CN202010699635.0A CN202010699635A CN111940741A CN 111940741 A CN111940741 A CN 111940741A CN 202010699635 A CN202010699635 A CN 202010699635A CN 111940741 A CN111940741 A CN 111940741A
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- die
- female die
- friction block
- shaping
- powder metallurgy
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- 238000007493 shaping process Methods 0.000 title claims abstract description 58
- 238000004663 powder metallurgy Methods 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 19
- 239000002184 metal Substances 0.000 claims abstract description 3
- 239000010720 hydraulic oil Substances 0.000 claims description 11
- 239000000956 alloy Substances 0.000 claims description 5
- 238000010892 electric spark Methods 0.000 claims description 5
- 238000000227 grinding Methods 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 5
- 238000003754 machining Methods 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 5
- 238000005498 polishing Methods 0.000 claims description 5
- 238000007514 turning Methods 0.000 claims description 5
- 229910000831 Steel Inorganic materials 0.000 claims description 4
- 239000010959 steel Substances 0.000 claims description 4
- 229910001315 Tool steel Inorganic materials 0.000 claims description 3
- 229910045601 alloy Inorganic materials 0.000 claims description 3
- 238000005520 cutting process Methods 0.000 claims description 2
- 230000008092 positive effect Effects 0.000 abstract description 2
- 238000012797 qualification Methods 0.000 abstract 1
- 238000004080 punching Methods 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 4
- 238000003825 pressing Methods 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000002407 reforming Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
Images
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/24—After-treatment of workpieces or articles
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- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Powder Metallurgy (AREA)
Abstract
The invention discloses a shaping die and a shaping method for a friction block of a powder metallurgy brake pad, wherein the shaping die comprises an upper punch, a lower punch and a female die, wherein a plurality of die cavities are arranged on the female die, and the number of the upper punches, the number of the lower punches and the number of the die cavities are the same; the upper punch comprises a forming section and a base; the lower punch comprises a forming section, a thinning section and a base, a central through hole penetrates through the interior of the whole lower punch, a profiling groove is arranged at the top end of the lower punch, and the profile of the profiling groove is consistent with that of a metal back plate of a friction block of the powder metallurgy brake pad; the cavity of the female die comprises a blank placing section and a forming section. Compared with the prior art, the invention has the following positive effects: the invention can effectively solve the problems of low shaping efficiency and poor flatness of the friction block of the powder metallurgy brake pad, can realize shaping of a plurality of brake pads at one time, and improves shaping efficiency and product flatness qualification rate.
Description
Technical Field
The invention relates to a shaping die and a shaping method for a friction block of a powder metallurgy brake pad.
Background
The powder metallurgy brake pad is used as a core component of a high-speed train braking system, and the kinetic energy of the train is converted into heat energy through the friction between the powder metallurgy brake pad and a brake disc, so that the deceleration and the stop of the train are realized. The main friction and wear parts of the powder metallurgy brake pad are powder metallurgy friction blocks which are assembled with a steel backing through a plurality of friction blocks. The friction block is prepared by the working procedures of mixing, pressing, sintering, shaping and the like. In the shaping process of the friction block, the shaping efficiency is low and the flatness is ultra-poor, which are main problems restricting the shaping production of the friction block.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention provides a shaping die and a shaping method for a brake pad friction block in powder metallurgy, and aims to solve the problems of low shaping efficiency and poor flatness of the brake pad friction block in powder metallurgy.
The technical scheme adopted by the invention for solving the technical problems is as follows: a shaping die for friction blocks of brake pads in powder metallurgy comprises an upper punch, a lower punch and a female die, wherein a plurality of die cavities are arranged on the female die, and the number of the upper punches, the number of the lower punches and the number of the die cavities are the same; the upper punch comprises a forming section and a base; the lower punch comprises a forming section, a thinning section and a base, a central through hole penetrates through the interior of the whole lower punch, a profiling groove is arranged at the top end of the lower punch, and the profile of the profiling groove is consistent with that of a metal back plate of a friction block of the powder metallurgy brake pad; the cavity of the female die comprises a blank placing section and a forming section.
The invention also provides a shaping method of the powder metallurgy brake pad friction block, which comprises the following steps:
firstly, mounting lower punches with the same number as that of the female die cavities on a lower connecting plate of a press, then mounting each die cavity of the female die and each lower punch in a matched manner, enabling the upper end surface of the female die and the upper end surface of a lower punch forming section to be flush, and finally mounting upper punches with the same number as that of the lower punches on an upper connecting plate of the press through female die center positioning;
secondly, the hydraulic oil cylinder drives the female die to rise by 5mm, and a friction block is respectively placed in each die cavity of the female die;
thirdly, the hydraulic oil cylinder drives the female die to continuously rise by 30-40 mm, so that the friction surface of the friction block is lower than the upper end surface of the female die;
fourthly, the hydraulic oil cylinder presses downwards to drive the upper die to punch into the die cavity of the female die, and the friction block is pressed and shaped;
after finishing shaping, firstly, driving a hydraulic oil cylinder of an upper punch to release pressure until the pressure is 0; then, the female die moves downwards until the upper end surface of the lower punch forming section is flush with the end surface of the female die, and the friction block is completely separated from the female die; and finally, taking out the product.
Compared with the prior art, the invention has the following positive effects:
the invention provides a multi-station shaping die and a method for a friction block of a powder metallurgy brake pad, which can effectively solve the problems of low shaping efficiency and poor flatness of the friction block of the powder metallurgy brake pad, and have the following specific advantages:
1) the invention adopts the multi-station shaping die, can realize one-time shaping of a plurality of workpieces and improve the shaping efficiency.
2) According to the multi-station shaping die, the flatness of the product can be ensured and the pass rate of the flatness of the product can be improved through the parallelism and height difference design of the stamping.
3) The multi-station shaping die can be used for shaping friction blocks with various structures, can reduce die switching, and effectively improves the production efficiency of the friction blocks of the powder metallurgy brake pad.
Drawings
The invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic structural view of a reforming mold of the present invention;
FIG. 2 is a schematic view of the present invention for performing compression shaping;
FIG. 3 is a schematic structural view of an upper punch;
FIG. 4 is a schematic structural view of a lower punch;
fig. 5 is a schematic structural view of the female mold.
Detailed Description
1) The invention provides a three-station shaping die and a three-station shaping method for a friction block of a powder metallurgy brake pad (the shaping die is not limited to three stations, and can be more or less). The die consists of three upper punches 1, three lower punches 2 and a female die 3 (shown in fig. 1).
2) The three-piece upper punch has completely consistent structure and material, comprises a forming section 1-1 and a base 1-2, and has the total length of about 80mm (as shown in figure 3). Wherein the length of the forming section is about 30mm, the roughness of the upper end surface and the side surface of the forming section is within Ra0.4, the upper end surface is contacted with the friction surface of the friction block in the shaping process, and the shaping and correction are carried out on the thickness and the flatness of the friction surface; the base is about 50mm long and mainly plays a role in installing and strengthening the strength of the die. The outer contour of the upper punch is of a cylindrical structure, the whole body is made of alloy tool steel or bearing steel material through the working procedures of heat treatment, electric spark machining, turning, grinding and polishing. The height difference of the three upper punches is less than or equal to 0.01mm, and the parallelism between the upper end surface of each upper punch and the bottom surface of the base is controlled within 0.01mm, so that the flatness of the product can be ensured, and the pass percent of the flatness of the product is improved.
3) The three-piece lower die punching structure is completely consistent in material, comprises five parts including a forming section 2-1, a thinning section 2-2, a base 2-3, a profiling groove 2-4 and a central through hole 2-5, and is about 120mm in total length (as shown in figure 4). Wherein: the length of the forming section is about 30mm, the roughness of the upper end surface and the side surface of the forming section is within Ra0.4, the upper end surface is contacted with the back plate surface of the friction block in the shaping process, and the shaping and correction are carried out on the thickness and the flatness of the back plate surface; the length of the thinning section is about 70mm, the size of the thinning section is 0.2mm thinner than that of the forming section, the thinning section mainly plays a role in deslagging in the shaping process, and the deformation of a die caused by slag clamping between the forming section and a female die is avoided; the base is about 20mm long and mainly plays a role in installing and strengthening the strength of the die; the profiling groove is mainly used for quickly positioning the friction block in the shaping process, and the profile of the profiling groove is consistent with that of the friction block back plate. The central through hole penetrates through the whole lower punch and is mainly used for exhausting and deslagging in the shaping process, and dust and impurities are prevented from being accumulated to cause die deformation. The outer contour of the lower punch is of a cylindrical structure, the whole body is made of alloy tool steel or bearing steel material through the working procedures of heat treatment, electric spark machining, turning, grinding and polishing. The height difference of the three lower punches is less than or equal to 0.01mm, and the parallelism between the upper end surface of each lower punch and the bottom surface of the base is controlled within 0.01mm, so that the flatness of the product can be ensured, and the pass percent of the flatness of the product is improved.
4) The female die comprises three die cavities with cylindrical structures, the three die cavities are uniformly distributed at 120 degrees and comprise a billet placing section 3-1 and a forming section 3-2, and the total height of the female die is about 70mm (as shown in figure 5). Wherein: the length of the billet placing section is about 5mm, the billet placing angle is 1-2 degrees, and the method is mainly used for quickly placing and guiding the friction block; the length of the forming section is 65mm, and the forming section is mainly used for guiding an upper punch and a lower punch; the roughness of the whole die cavity of the female die is within Ra0.4, so that the friction force between the female die and the upper die punch and the friction force between the female die and the lower die punch in the shaping process can be reduced, and the rapid abrasion of the die is avoided. The female die is made of hard alloy materials and is manufactured through the working procedures of turning, heat treatment, wire cutting, electric spark machining, grinding, polishing and the like.
The shaping of the friction block is only to correct the thickness and the flatness of the friction block, and the cavity of the shaping female die is not contacted with the outer contour of the friction block in the actual shaping process. Therefore, the upper punch, the lower punch and the female die of the shaping die are all designed to be of cylindrical structures, the shaping die can be used for shaping friction blocks with various outer contours, time loss caused by frequent switching of the die in the production process is avoided, and production efficiency is improved.
5) The pressing method comprises the following steps:
the method comprises the following steps: firstly, punching and mounting three lower dies on a lower connecting plate of a press, then respectively installing three die cavities of a female die and the three lower dies in a punching fit manner, enabling the upper end surface of the female die and the upper end surface of a punching forming section of the lower dies to be flush, and finally, punching and mounting three upper dies on an upper connecting plate of the press through the center positioning of the female die;
secondly, the hydraulic oil cylinder drives the female die to rise by about 5mm, and three friction blocks 4 are respectively placed in three die cavities of the female die;
thirdly, the hydraulic oil cylinder drives the female die to continuously rise by 30-40 mm, so that the friction surface of the friction block is lower than the upper end surface of the female die;
step four, the hydraulic oil cylinder downwards pressurizes and drives the upper die to punch into the die cavity of the female die, the friction block is pressurized and shaped, the pressure is maintained for 3-10 seconds, and the pressure is maintained for 60-80 tons (shown in figure 2);
after finishing shaping, firstly, the upper die is flushed and decompressed until the pressure is 0; then, the female die moves downwards until the upper end surface of the lower punch forming section is flush with the end surface of the female die, and the friction block is completely separated from the female die; and finally, taking out the product.
Claims (10)
1. The utility model provides a powder metallurgy brake lining clutch block plastic mould which characterized in that: the stamping die comprises an upper stamping, a lower stamping and a female die, wherein a plurality of die cavities are arranged on the female die, and the number of the upper stamping, the number of the lower stamping and the number of the die cavities are the same; the upper punch comprises a forming section and a base; the lower punch comprises a forming section, a thinning section and a base, a central through hole penetrates through the interior of the whole lower punch, a profiling groove is arranged at the top end of the lower punch, and the profile of the profiling groove is consistent with that of a metal back plate of a friction block of the powder metallurgy brake pad; the cavity of the female die comprises a blank placing section and a forming section.
2. The powder metallurgy brake lining friction block shaping die of claim 1, wherein: the length of the forming section of the upper punch is 30mm, and the roughness of the upper end surface and the roughness of the side surface of the forming section are both within Ra0.4; the base of the upper punch is 50mm long.
3. The powder metallurgy brake lining friction block shaping die of claim 1, wherein: the length of the forming section of the lower punch is 30mm, and the roughness of the upper end surface and the roughness of the side surface of the forming section are both within Ra0.4; the thinning section of the lower punch is 70mm long, and the size of the lower punch is 0.2mm thinner than that of the forming section; the base of the lower punch is 20mm long.
4. The powder metallurgy brake lining friction block shaping die of claim 1, wherein: the outer contours of the upper punch and the lower punch are both cylindrical structures, the whole body is made of alloy tool steel or bearing steel materials through the working procedures of heat treatment, electric spark machining, turning, grinding and polishing.
5. The powder metallurgy brake lining friction block shaping die of claim 1, wherein: the height difference of all the upper punches and the height difference of all the lower punches are less than or equal to 0.01mm, and the parallelism between the upper end surfaces of the upper punches and the lower punches and the bottom surface of the base is controlled within 0.01 mm.
6. The powder metallurgy brake lining friction block shaping die of claim 1, wherein: the blank placing section of the female die is 5mm long, and the blank placing angle is 1-2 degrees; the forming section of the female die is 65mm long; the overall cavity roughness of the female die is within Ra0.4.
7. The powder metallurgy brake lining friction block shaping die of claim 1, wherein: the female die is made of hard alloy materials and is manufactured through the working procedures of turning, heat treatment, wire cutting, electric spark machining, grinding and polishing.
8. The powder metallurgy brake lining friction block shaping die of claim 1, wherein: the female die cavity is of a cylindrical structure.
9. A shaping method of a powder metallurgy brake pad friction block is characterized by comprising the following steps: the method comprises the following steps:
firstly, mounting lower punches with the same number as that of the female die cavities on a lower connecting plate of a press, then mounting each die cavity of the female die and each lower punch in a matched manner, enabling the upper end surface of the female die and the upper end surface of a lower punch forming section to be flush, and finally mounting upper punches with the same number as that of the lower punches on an upper connecting plate of the press through female die center positioning;
secondly, the hydraulic oil cylinder drives the female die to rise by 5mm, and a friction block is respectively placed in each die cavity of the female die;
thirdly, the hydraulic oil cylinder drives the female die to continuously rise by 30-40 mm, so that the friction surface of the friction block is lower than the upper end surface of the female die;
fourthly, the hydraulic oil cylinder presses downwards to drive the upper die to punch into the die cavity of the female die, and the friction block is pressed and shaped;
after finishing shaping, firstly, driving a hydraulic oil cylinder of an upper punch to release pressure until the pressure is 0; then, the female die moves downwards until the upper end surface of the lower punch forming section is flush with the end surface of the female die, and the friction block is completely separated from the female die; and finally, taking out the product.
10. The method for shaping the friction block of the powder metallurgy brake pad as claimed in claim 9, wherein: and step four, the pressure maintaining time for pressurizing and shaping the friction block is 3-10 seconds, and the pressure maintaining pressure is 60-80 tons.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010699635.0A CN111940741A (en) | 2020-07-20 | 2020-07-20 | Powder metallurgy brake pad friction block shaping die and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010699635.0A CN111940741A (en) | 2020-07-20 | 2020-07-20 | Powder metallurgy brake pad friction block shaping die and method |
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| Publication Number | Publication Date |
|---|---|
| CN111940741A true CN111940741A (en) | 2020-11-17 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010699635.0A Pending CN111940741A (en) | 2020-07-20 | 2020-07-20 | Powder metallurgy brake pad friction block shaping die and method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113084161A (en) * | 2021-03-30 | 2021-07-09 | 博深股份有限公司 | Universal sintering mold for powder metallurgy brake pad and use method |
| CN113084170A (en) * | 2021-04-05 | 2021-07-09 | 博深股份有限公司 | Friction block sintering mold suitable for automatic production and using method |
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| JPH0257622A (en) * | 1988-08-22 | 1990-02-27 | Toyota Motor Corp | Method of sizing flanged tooth-shaped parts |
| JPH06145715A (en) * | 1992-11-05 | 1994-05-27 | Seiko Instr Inc | Production of parts from powder |
| CN204035566U (en) * | 2014-07-23 | 2014-12-24 | 东莞劲胜精密组件股份有限公司 | The shaping mould of powder metallurgy structural part |
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| CN110497149A (en) * | 2019-07-31 | 2019-11-26 | 山东金麒麟股份有限公司 | A kind of drum brakes piece making method |
| CN111112606A (en) * | 2020-01-17 | 2020-05-08 | 中铁隆昌铁路器材有限公司 | Powder metallurgy brake pad friction block pressing die and method |
| CN212945424U (en) * | 2020-07-20 | 2021-04-13 | 中铁隆昌铁路器材有限公司 | Powder metallurgy brake lining friction block shaping die |
-
2020
- 2020-07-20 CN CN202010699635.0A patent/CN111940741A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0257622A (en) * | 1988-08-22 | 1990-02-27 | Toyota Motor Corp | Method of sizing flanged tooth-shaped parts |
| JPH06145715A (en) * | 1992-11-05 | 1994-05-27 | Seiko Instr Inc | Production of parts from powder |
| CN204035566U (en) * | 2014-07-23 | 2014-12-24 | 东莞劲胜精密组件股份有限公司 | The shaping mould of powder metallurgy structural part |
| CN205437141U (en) * | 2016-02-26 | 2016-08-10 | 深圳市梦之坊通信产品有限公司 | Powder metallurgy embossing mold utensil of metal mobile phone shell |
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| CN207071683U (en) * | 2017-07-24 | 2018-03-06 | 重庆江洲粉末冶金科技有限公司 | A kind of belt pulley shaping tooling |
| CN110497149A (en) * | 2019-07-31 | 2019-11-26 | 山东金麒麟股份有限公司 | A kind of drum brakes piece making method |
| CN111112606A (en) * | 2020-01-17 | 2020-05-08 | 中铁隆昌铁路器材有限公司 | Powder metallurgy brake pad friction block pressing die and method |
| CN212945424U (en) * | 2020-07-20 | 2021-04-13 | 中铁隆昌铁路器材有限公司 | Powder metallurgy brake lining friction block shaping die |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113084161A (en) * | 2021-03-30 | 2021-07-09 | 博深股份有限公司 | Universal sintering mold for powder metallurgy brake pad and use method |
| CN113084170A (en) * | 2021-04-05 | 2021-07-09 | 博深股份有限公司 | Friction block sintering mold suitable for automatic production and using method |
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