US20070141952A1 - Fluid abrasive machining method and apparatus thereof - Google Patents

Fluid abrasive machining method and apparatus thereof Download PDF

Info

Publication number
US20070141952A1
US20070141952A1 US11/641,201 US64120106A US2007141952A1 US 20070141952 A1 US20070141952 A1 US 20070141952A1 US 64120106 A US64120106 A US 64120106A US 2007141952 A1 US2007141952 A1 US 2007141952A1
Authority
US
United States
Prior art keywords
pressure
abrasive machining
fluid
machined
work
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US11/641,201
Other languages
English (en)
Inventor
Yuji Soda
Tsuyoshi Goto
Takayuki Minoshima
Akinao Miura
Shigeya Kato
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Denso Corp
Original Assignee
Denso Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Denso Corp filed Critical Denso Corp
Assigned to DENSO CORPORATION reassignment DENSO CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: GOTO, TSUYOSHI, KATO, SHIGEYA, MINOSHIMA, TAKAYUKI, MIURA, AKINAO, SODA, YUJI
Publication of US20070141952A1 publication Critical patent/US20070141952A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B31/00—Machines or devices designed for polishing or abrading surfaces on work by means of tumbling apparatus or other apparatus in which the work and/or the abrasive material is loose; Accessories therefor
    • B24B31/10—Machines or devices designed for polishing or abrading surfaces on work by means of tumbling apparatus or other apparatus in which the work and/or the abrasive material is loose; Accessories therefor involving other means for tumbling of work
    • B24B31/116—Machines or devices designed for polishing or abrading surfaces on work by means of tumbling apparatus or other apparatus in which the work and/or the abrasive material is loose; Accessories therefor involving other means for tumbling of work using plastically deformable grinding compound, moved relatively to the workpiece under the influence of pressure

Definitions

  • the present invention relates to a fluid abrasive machining method and to a fluid abrasive machining apparatus for effecting the method and, more particularly, to a machining method, and to a machining apparatus with high precision, for drilling a fine pore using an abrasive slurry.
  • a fine pore formed with high precision for example, a tip of a fuel injection nozzle, an injection hole of a caburetor, an orifice for regulating a flow rate of fluid, an injection nozzle of a printer, etc.
  • Laser machining, electro-beam machining, electrical discharge machining and the like are known as machining methods for drilling a fine pore.
  • a fluid abrasive machining method may be employed.
  • a fluid abrasive machining method is used for drilling a fine pore of an orifice of a diesel common rail type fuel injector which is applied to a diesel engine.
  • a diesel engine tends to have common rail type fuel injectors and a diesel engine having common rail type fuel injectors is installed on a vehicle in the range from a small automobile with approximately 80 KW output power to a large truck. If the output flow rate of the fuel injector includes some errors, the fuel consumption efficiency of a diesel engine is decreased, so that an economic performance thereof is deteriorated and, as a result, polluting contaminates in the exhaust gas are increased and the environment may be deteriorated.
  • the flow rate error of a diesel common rail type injector is greatly influenced by a static oil flow rate precision of an orifice which is a component of the injector so that the orifice is finished by the fluid abrasive machining method in order to adjust the size of the orifice.
  • a slurry which is produced as a mixture of grinding particles and oil and is discharged from a cylinder by a movement of a piston, flows through the orifice, so that the diameter of an orifice hole is enlarged and the inlet periphery of the orifice hole is rounded.
  • a measuring method in which the diameter of the fine pore is measured by measuring the flow rate of a specific fluid, when the specific fluid flows through the fine pore at a constant pressure may be used.
  • Some products such as a fuel injection nozzle, which have a function to pass a fluid at a specific flow rate, have a product performance which is determined by a machining precision. The product performance of such a product can be directly judged from a target machining precision value thereof which can be examined by measuring a flow rate of fluid flowing though the product.
  • the finishing state of a product can be judged and whether the product has a specified performance due to the machining can be confirmed by measuring the flow rate of the abrasive fluid so that such a measuring method may be performed.
  • an injection hole for injecting fuel has been required to have an extremely high accuracy in order to attain a flow rate performance standard thereof and, therefore, conventionally it was common that the flow rate of a slurry which was an abrasive material or a displacement (movement distance) of a piston corresponding to the flow rate of the slurry was monitored and just when the flow rate of the slurry reached a specified flow rate value or the displacement (movement distance) of the piston reached a specified alternate value corresponding to the specified flow rate of the slurry, the machining operation was terminated (refer to, for example, Patent document 1 or 2). According to the conventional method, however, an expensive flow meter or an expensive monitoring device was required so that there was a problem in which the cost of facilities increases.
  • Patent document 2 Japanese Examined Patent Publication (Kokoku) No. 7-85866
  • Patent document 3 Japanese Unexamined Patent Publication (Kokai) No. 2004-284014
  • an object of the present invention is to provide a fluid abrasive machining method capable of controlling a fluid abrasive machining without using an expensive flow meter, and an apparatus for performing the method.
  • a fluid abrasive machining method for abrasively machining a fine pore on a work ( 5 ) to be machined by supplying a slurry ( 7 ), which is an abrasive machining fluid, from a supplying device ( 2 ) to the work to be machined comprises steps of: supplying the slurry to the work to be machined from the supplying device; measuring a first pressure (P 1 ) at an upstream discharge side of the supplying device; measuring a second pressure (P 2 ) at a downstream of a measuring point of the first pressure (P 1 ) and at an upstream side of the work to be machined; calculating a pressure difference (dp) between the first pressure and the second pressure; terminating a machining operation when the pressure difference dp reaches a specific pressure difference value.
  • control is performed so that the first pressure (P 1 ) is always maintained at a substantially constant pressure during a fluid abrasive machining operation.
  • the present aspect it is possible to machine a fine pore, which has a high precision and has a specific flow rate performance, on a work by a way in which the first pressure (P 1 ) is controlled to be always maintained at a substantially constant pressure, the second pressure (P 2 ) is monitored and when the second pressure (P 2 ) reaches a specific pressure value, the operation of a machining is terminated.
  • a control is performed so that the second pressure (P 2 ) is always maintained at a substantially constant pressure in a fluid abrasive machining operation.
  • the present aspect it is possible to machine a fine pore, which has a high precision and has a specific flow rate performance, on a work by a way in which the second pressure (P 2 ) is controlled to be always maintained at a substantially constant pressure, the first pressure (P 1 ) is monitored and when the first pressure (P 1 ) reaches a specific pressure value, the operation of a machining is terminated.
  • the object to be machined is a fine pore of a fuel injector for a diesel engine.
  • a fluid abrasive machining apparatus ( 100 ) for abrasively machining a fine pore on a work ( 5 ) to be machined by supplying a slurry ( 7 ), which is an abrasive machining fluid, to the work to be machined comprises: a supplying device ( 2 ) for supplying the slurry ( 7 ); a measuring means for measuring a pressure difference (dp) between a first pressure (P 1 ) at an upstream in a discharge side of the supplying device and a second pressure (P 2 ) at a downstream of a measuring point of the first pressure (P 1 ) and at an upstream side of the work to be machined; and a terminating means for terminating a machining operation when the pressure difference (dp) reaches a specific pressure difference value.
  • the fluid abrasive machining apparatus further comprises: a first pressure sensor ( 14 ) for measuring the first pressure (P 1 ); and a second pressure sensor ( 15 ) for measuring the second pressure (P 2 ).
  • a measuring means for measuring the pressure difference (dp) is concretely described.
  • the work ( 5 ) to be machined is a fuel injector for a diesel engine.
  • FIG. 1 is a diagrammatic illustration showing a configuration of an embodiment of a fluid abrasive machining apparatus according to the present invention.
  • FIG. 2 is a graph showing a relationship between a flow rate of a slurry and a piping line pressure loss in a fluid abrasive machining method.
  • a flow rate of fluid flowing through a product is proportional to the pressure loss dP between an upstream side (for example, a supply side of a slurry (abrasive fluid)) and a downstream side (for example, just in front of the product) of a piping line of the fluid abrasive machining apparatus.
  • dPf is a pressure loss
  • D is an inner diameter of a piping line
  • L is a length
  • ⁇ is a viscosity coefficient of a slurry
  • u is a mean velocity of the slurry in a piping line.
  • this equation suggests that the flow rate performance of the product (the flow rate of a slurry flowing through the product at a specific pressure) can be controlled by monitoring the pressure loss in an arbitrary piping line through which the slurry flows, during an abrasive machining operation.
  • FIG. 1 diagrammatically shows a structure of a first embodiment of a fluid abrasive machining apparatus according to the present invention.
  • the fluid abrasive machining apparatus 100 according to the first embodiment comprises: a slurry tank 1 for storing a slurry 7 which functions as abrasive fluid and comprises a mixer 4 ; a slurry supplying device 2 for sucking the slurry 7 from the slurry tank 1 to supply it to a work 5 to be machined; and a control section 20 for controlling the fluid abrasive machining apparatus 100 .
  • the work 5 to be machined is a fuel injection nozzle for an engine.
  • the slurry supplying device 2 is a cylinder 2 which comprises a piston 6 which reciprocates in the cylinder 2 and the slurry 7 is sucked and pumped by a reciprocating motion of the piston 6 .
  • the fluid abrasive machining apparatus 100 further comprises three control valves. A first control valve 11 is arranged on the upstream of the cylinder 2 , a second control valve 12 is arranged on the downstream of the cylinder 2 and a third control valve 13 is arranged on the upstream of the nozzle 5 , respectively, as shown in FIG. 1 .
  • the fluid abrasive machining apparatus 100 further comprises a first pressure sensor 14 arranged near and on the downstream of the second control valve 12 and a second pressure sensor 15 arranged near and on the upstream of the third control valve 13 .
  • the slurry tank 1 , the cylinder 2 and the nozzle (work) 5 are connected with each other by pipes on which the control valves 11 , 12 and 13 and the pressure sensors 14 and 15 are arranged.
  • the control section 20 comprises, for example, a sensor amplifier 21 which is input with pressure signals from the pressure sensor 14 , 15 to amplify the pressure signals, a digital converter 22 for converting an analogue pressure signal into a digital pressure signal and a sequencer (a programmable controller) 23 which receives the pressure signals from the pressure sensors and comprises a control program.
  • the control section 20 receives the pressure signals from the pressure sensors 14 , 15 to process and calculate the values of the pressure signals and controls the fluid abrasive machining apparatus 100 .
  • the control section 20 may have known constructions, which includes a control circuit or includes a personal computer, etc., other than the construction described above.
  • the type “A” control in which a control is performed at the upstream side of the piping line is employed.
  • the pressure of the upstream side of the piping line (the measured pressure of a first pressure sensor 14 ) is maintained at a constant pressure
  • the fluid abrasive machining operation is terminated when the pressure of the downstream side of the piping line (the measured pressure of a second pressure sensor 15 ) reaches a predetermined pressure, and thereby the required flow rate performance of the product is realized.
  • the piston 6 is moved to a rod side of the cylinder 2 and then the cylinder 2 sucks the slurry 7 from the slurry tank 1 .
  • the first control valve 11 is opened and the second control valve 12 is closed.
  • the first control valve 11 is closed and the second control valve 12 is opened.
  • the third control valve 13 is opened, the piston 6 is moved to a cylinder direction (head side) in the cylinder 2 and the slurry is pumped to the nozzle 5 .
  • the piston 6 is moved so that the pressure P 1 of the first pressure sensor 14 is maintained at constant.
  • the target flow rate of the slurry and the approximate value of the pressure at the first sensor 14 at the same time are previously noted.
  • the pressure of the first sensor 14 and that of the second sensor 15 are always transmitted to, and are monitored by, the control section 20 .
  • the pressure loss at the nozzle 5 is large so that the flow rate of the slurry 7 is low and the pressure difference dp between the pressure P 1 of the first sensor 14 and the pressure P 2 of the second sensor 15 is small.
  • the diameter of the nozzle 5 is increased, the flow rate of the slurry 7 flowing through the nozzle increases and the pressure difference dp increases.
  • the pressure P 1 is maintained at constant, the pressure P 2 is monitored and is compared with the specific pressure value which is previously memorized in the control section 20 .
  • the third control valve 13 is closed and the operation of the cylinder 2 is terminated.
  • the pressure difference dp reaches the specific pressure difference value so that the flow rate of the fluid flowing through the nozzle 5 must reach the specific flow rate as explained above.
  • the fluid abrasive machining of the nozzle 5 which is a work to be machined, is performed so that the nozzle 5 has a specific working performance.
  • the fluid abrasive machining apparatus 100 may be formed so that the third control valve 13 is closed and the slurry 7 from the cylinder 2 is bypassed when the machining operation is stopped.
  • a second embodiment of the present invention will be now described below.
  • the construction of the fluid abrasive machining apparatus of the second embodiment is basically the same as that of the first embodiment and has the construction shown in FIG. 1 .
  • the difference between the first embodiment and the second embodiment is only in a way of controlling the fluid abrasive machining operation. Therefore, the construction of the fluid abrasive machining apparatus of the second embodiment is not described here.
  • the type “B” control in which a control is performed at the downstream side of the piping line is employed.
  • the pressure P 2 of the downstream side of the piping line is maintained at constant and at the time when the pressure P 1 of the upstream side reaches a specific pressure value, the fluid abrasive machining operation is terminated and thereby, the required flow rate of the fluid flowing through the product (flow rate performance of the product) is realized.
  • the fluid abrasive machining method and the operation of the fluid abrasive machining apparatus 100 shown in FIG. 1 are basically the same as those of the first embodiment.
  • the different points of the second embodiment from the first embodiment are in that the cylinder 2 is controlled so that the pressure P 2 of the second pressure sensor 15 is maintained at a constant pressure and in that the pressure of the first pressure sensor 14 is monitored and when the pressure value of the first pressure sensor 14 reaches a previously memorized specific value, the third control valve 13 is closed and the operation of the cylinder 2 is terminated so that the operation of the fluid abrasive machining is terminated.
  • the cylinder 2 is controlled so that the pressure difference dp is increased, in other words, the pressure of the first pressure sensor 14 is increased, while the pressure P 2 of the second sensor 15 is maintained at a constant pressure and, finally, if the pressure P 1 has reached a specific pressure value, the pressure difference dp also reaches a specific pressure difference value.
  • the flow rate of the slurry reaches a specific flow rate value.
  • a highly precise machining can be performed by monitoring pressure variations of a fluid flowing through the machined fine pore using a cheap pressure sensor, and without using an expensive flow meter, and by terminating the machining operation when the pressure reaches a specific pressure value and at the same time, the cost of the machining apparatus can be reduced.
  • the above-mentioned pressure variations are caused as the result of the machining.
  • the present apparatus is not required to use a flow meter, it has endurance.
  • the fluid abrasive machining method or the fluid abrasive machining apparatus in the second embodiment of the present invention can be expected to provide the same effects as those in the fluid abrasive machining method or the fluid abrasive machining apparatus of the above-mentioned first embodiment.
  • the supply device for supplying a slurry to the orifice which is a machined work is a cylinder which is a plunger type pump, however, the present invention is not limited to this and, for example, the supply device may be known types of pumps other than a plunger type pump or a known type of fluid supplying device.
  • a slurry supply device, that is, a cylinder 2 is provided, however more than two of slurry supply devices may be provided.
  • the present invention is not limited to this and for example, the present invention may be applied to a machining of an orifice other than the above or to a machining of a precise fine pore, such as a tip of a fuel injection nozzle, an injection hole of a caburetor, an orifice for regulating fluid flow-rate, an injection nozzle for a printer, etc.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
  • Grinding-Machine Dressing And Accessory Apparatuses (AREA)
US11/641,201 2005-12-19 2006-12-18 Fluid abrasive machining method and apparatus thereof Abandoned US20070141952A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2005364853A JP4569462B2 (ja) 2005-12-19 2005-12-19 流体研磨加工方法及び装置
JP2005-364853 2005-12-19

Publications (1)

Publication Number Publication Date
US20070141952A1 true US20070141952A1 (en) 2007-06-21

Family

ID=38089660

Family Applications (1)

Application Number Title Priority Date Filing Date
US11/641,201 Abandoned US20070141952A1 (en) 2005-12-19 2006-12-18 Fluid abrasive machining method and apparatus thereof

Country Status (3)

Country Link
US (1) US20070141952A1 (ja)
JP (1) JP4569462B2 (ja)
DE (1) DE102006058288A1 (ja)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103286642A (zh) * 2013-05-14 2013-09-11 太原理工大学 一种液体磁性磨具孔光整加工装置

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4995949A (en) * 1986-03-21 1991-02-26 Extrude Hone Corporation Orifice sizing using chemical, electrochemical, electrical discharge machining, plating, coating techniques
US5054247A (en) * 1986-03-21 1991-10-08 Extrude Hone Corporation Method of controlling flow resistance in fluid orifice manufacture
US5807163A (en) * 1995-08-04 1998-09-15 Dynetics Corporation Method and apparatus for controlling the diameter and geometry of an orifice with an abrasive slurry
US6132482A (en) * 1996-11-12 2000-10-17 Dynetics Corporation Abrasive liquid slurry for polishing and radiusing a microhole
US6306011B1 (en) * 1998-05-11 2001-10-23 Dynetics Corporation System for controlling the size and surface geometry of an orifice
US6500050B2 (en) * 2000-09-06 2002-12-31 Extrude Hone Corporation High precision abrasive flow machining apparatus and method
US6575815B1 (en) * 1999-09-01 2003-06-10 Robert Bosch Gmbh Process for calibrating throttle bores, in particular in injection valves for internal combustion engines, and device for executing the process

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61206821U (ja) * 1985-06-17 1986-12-27
JPH0863235A (ja) * 1994-08-24 1996-03-08 Burutsukusu Instr Kk 差圧式質量流量コントロール装置
JP4015751B2 (ja) * 1998-04-30 2007-11-28 株式会社技術開発総合研究所 差圧式流量計
JP3975186B2 (ja) * 2003-09-03 2007-09-12 株式会社不二越 微細穴の流動加工装置

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4995949A (en) * 1986-03-21 1991-02-26 Extrude Hone Corporation Orifice sizing using chemical, electrochemical, electrical discharge machining, plating, coating techniques
US5054247A (en) * 1986-03-21 1991-10-08 Extrude Hone Corporation Method of controlling flow resistance in fluid orifice manufacture
US5807163A (en) * 1995-08-04 1998-09-15 Dynetics Corporation Method and apparatus for controlling the diameter and geometry of an orifice with an abrasive slurry
US6132482A (en) * 1996-11-12 2000-10-17 Dynetics Corporation Abrasive liquid slurry for polishing and radiusing a microhole
US6306011B1 (en) * 1998-05-11 2001-10-23 Dynetics Corporation System for controlling the size and surface geometry of an orifice
US6575815B1 (en) * 1999-09-01 2003-06-10 Robert Bosch Gmbh Process for calibrating throttle bores, in particular in injection valves for internal combustion engines, and device for executing the process
US6500050B2 (en) * 2000-09-06 2002-12-31 Extrude Hone Corporation High precision abrasive flow machining apparatus and method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103286642A (zh) * 2013-05-14 2013-09-11 太原理工大学 一种液体磁性磨具孔光整加工装置

Also Published As

Publication number Publication date
DE102006058288A1 (de) 2007-06-21
JP2007167967A (ja) 2007-07-05
JP4569462B2 (ja) 2010-10-27

Similar Documents

Publication Publication Date Title
CN101238281B (zh) 用于控制内燃机喷射系统的方法和装置
JP2625135B2 (ja) 流体材料吐出装置及び方法
US7427227B2 (en) Method and apparatus for fluid polishing
CN1643466A (zh) 质量流控制器
CN101979849A (zh) 流体传送系统和方法
JPH03125098A (ja) 潤滑監視システム
CN102011656A (zh) 用于控制燃料压力的方法和系统
US10036314B2 (en) Fuel system flush circuitry and method for operating the same
CN102635425A (zh) 用于将液体计量到内燃机的废气管中的装置及方法
CN217276843U (zh) 一种自激振荡喷嘴工作特性测试系统
CN103857897A (zh) 气体燃料供应线路中的用于管理质量流量和抑制压力脉动的模块
US20070141952A1 (en) Fluid abrasive machining method and apparatus thereof
US6575815B1 (en) Process for calibrating throttle bores, in particular in injection valves for internal combustion engines, and device for executing the process
CN105275649A (zh) 用于操作内燃发动机的方法和发动机控制单元
CN1906404B (zh) 阀体、流体喷射器以及用于制造阀体的工艺方法
CN102137998B (zh) 用于分析高功率热能发动机内所使用的燃料喷射系统提供的步进式喷射流率的方法
US20050003740A1 (en) Method for hydro-erosive rounding of an edge of a part and use thereof
JP3863292B2 (ja) 液体供給装置
CN201212495Y (zh) 超高压清洗机用平衡型调压系统
EP1380780A2 (en) Valve with operation parameter set at assembly and pump using same
JP2012502218A (ja) 高出力熱機関において使用される燃料注入システムによりもたらされる段階的な注入速度を分析するための装置
JP2009276328A (ja) 圧力センサの評価装置及び評価方法
US10184436B2 (en) Fluid injector supply system and method for operating same
CN107133424A (zh) 一种脉动式燃油喷射系统喷油器针阀位移曲线预测方法
CN111069980A (zh) 喷油嘴喷孔挤压研磨装置及方法

Legal Events

Date Code Title Description
AS Assignment

Owner name: DENSO CORPORATION, JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SODA, YUJI;GOTO, TSUYOSHI;MINOSHIMA, TAKAYUKI;AND OTHERS;REEL/FRAME:018726/0075

Effective date: 20061208

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION