阅读说明：本技术 用于柴油机机架断续螺纹孔加工的螺纹铣刀及方法 (Thread milling cutter and method for machining intermittent threaded holes of diesel engine frame ) 是由 邓吉明 高少鹏 顾亮 韩健 于 2019-08-15 设计创作，主要内容包括：一种用于柴油机机架断续螺纹孔加工的螺纹铣刀及方法,在龙门铣床上采用螺纹铣刀,通过数控程序指令以圆弧螺旋插补的方式,在断续螺纹孔中从孔底自下而上自动完成断续螺纹孔的螺纹的粗铣和精铣加工；螺纹铣刀包括刀杆、刀头和刀片,刀头与刀杆焊接成一体,中心设有沿轴向贯通的冷却孔,刀片沿圆周均匀分布地安装在刀头的下端面,该下端面设有冷却槽,该冷却槽一端连通所述冷却孔,另一端开口于所述刀片的切削刃处,刀片上设置有断屑槽,冷却液由冷却孔中流出,经过冷却槽喷射至刀片的切削刃处,将铁屑裹挟排出,改变了排屑方向,防止该铁屑进入上钢板与下钢板之间的缝隙。本发明有效避免了铁屑进入夹缝内导致的卡刀及烂牙风险,提高了断续螺纹孔的加工质量和效率。(A thread milling cutter and method used for the intermittent screwed hole of diesel engine stander to process, use the thread milling cutter on the planer-type milling machine, through the numerical control program order in the way of the helical interpolation of circular arc, finish rough milling and finish milling of the whorl of the intermittent screwed hole automatically from bottom to top in the intermittent screwed hole; thread milling cutter includes cutter arbor, tool bit and blade, and the tool bit welds integratively with the cutter arbor, and the center is equipped with along the cooling hole that the axial link up, and the lower terminal surface at the tool bit is installed along circumference evenly distributed to the blade, should lower terminal surface be equipped with the cooling bath, this cooling bath one end intercommunication the cooling hole, other end opening in the cutting edge department of blade is provided with the chip breaker groove on the blade, and the coolant liquid flows out in by the cooling hole, sprays the cutting edge department to the blade through the cooling bath, wraps up in iron fillings and carries the discharge, has changed the chip removal direction, prevents that this iron fillings from getting into the gap between steel sheet and the lower steel sheet. The invention effectively avoids the risks of knife clamping and tooth decay caused by scrap iron entering the crack, and improves the processing quality and efficiency of the interrupted threaded hole.)

1. The utility model provides a thread milling cutter for processing of intermittent screw hole of diesel engine frame, intermittent screw hole link up mutual welded last steel sheet and lower steel sheet, should go up the steel sheet and have the gap down between the steel sheet, its characterized in that: the thread milling cutter comprises a cutter bar, a cutter head and a plurality of blades; the cutter head and the lower end of the cutter bar are welded into a whole, the plurality of blades are uniformly distributed on the lower end surface of the cutter head along the circumference, the centers of the interiors of the cutter bar and the cutter head are provided with cooling holes which are communicated along the axial direction, the lower end surface of the cutter head is provided with a plurality of cooling grooves, one ends of the cooling grooves are communicated with the cooling holes, the other ends of the cooling grooves are opened at the cutting edges of the blades, and chip breakers are arranged on the blades; the coolant liquid by flow in the cooling hole, process the cooling bath sprays to the cutting edge department of blade, will pass through the iron fillings that the chip breaker has changed the shape are wrapped up in and are carried the discharge to change the chip removal direction, prevent this iron fillings entering go up the gap between steel sheet and the lower steel sheet.

2. A thread milling cutter for interrupted thread hole machining of diesel engine frames according to claim 1, characterized in that: the lower end surface of the cutter head is provided with an embedded blade mounting groove, and the blade is locked and fixed in the blade mounting groove through a screw.

3. A thread milling cutter for interrupted thread hole machining of diesel engine frames according to claim 1, characterized in that: the cutting tip of the insert is oriented in the radial direction, and the positive radial rake angle of the insert is yf equal to 10 °.

4. A thread milling cutter for interrupted thread hole machining of diesel engine frames according to claim 1, characterized in that: the cutter arbor adopt whole carbide material to make, the tool bit is made for steel, the blade is through PVD physics picture layer processing.

5. A thread milling cutter for interrupted thread hole machining of diesel engine frames according to claim 1, characterized in that: the number of the blades is 5.

6. A thread milling cutter for interrupted thread hole machining of diesel engine frames according to claim 1, characterized in that: the blade can be used for 4 times by being installed forwards and backwards.

7. A method for machining interrupted threaded holes of a diesel engine frame using the thread milling cutter according to claim 1, characterized in that: and the thread milling cutter is adopted on a gantry milling machine, and the rough milling and the finish milling of the threads of the intermittent threaded holes are automatically finished in the intermittent threaded holes from bottom to top in a circular arc spiral interpolation mode through numerical control program instructions.

8. The method for machining the interrupted thread hole of the diesel engine frame according to claim 7, wherein: the processing method comprises the following steps:

1) Placing the rack on the table top of the planer type milling machine, leveling, straightening, clamping and pressing, and setting a zero position;

2) the blades are embedded into the blade mounting grooves of the cutter heads, the blades are locked and fixed by screws, and the assembled thread milling cutter is mounted on a main shaft of the planer type milling machine;

3) And through numerical control program instructions, the rough milling and the finish milling of the threads of all the interrupted threaded holes on the rack are automatically finished from bottom to top in the interrupted threaded holes in a circular arc spiral interpolation mode.

Technical Field

The invention relates to metal cutting machining of marine diesel engine parts, in particular to a thread milling cutter and a thread milling method for machining intermittent threaded holes of a diesel engine frame, and belongs to the technical field of diesel engine manufacturing.

Background

The frame is one of important parts of the marine diesel engine, the upper part of the frame is connected with a cylinder body, the frame structure is special, the upper plane is provided with a plurality of deep threaded holes, the part is formed by welding two steel plates, please refer to fig. 1 and fig. 2, the joint of the two steel plates is easy to deform due to welding heat, a crack is difficult to avoid, and the threaded holes are deep holes, so that the difficulty is brought to the thread processing of the deep threaded holes.

At present, the conventional machining method of the deep threaded hole adopts a screw tap to tap threads, however, in the machining method, iron chips can enter a crack between an upper steel plate and a lower steel plate in the process, and the iron chips can participate in secondary cutting to cause tool clamping and lead to tooth decay of the threaded hole or tooth collapse of the screw tap, so that the machining quality and efficiency of the threaded hole are difficult to guarantee by the traditional machining method. In a word, the conventional method for tapping the threaded hole by the screw tap has the problems of low machining efficiency, no quality guarantee and high machining cost.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the thread milling cutter and the method for machining the intermittent threaded holes of the diesel engine rack overcome the defect of machining the intermittent threaded holes by a conventional screw tap, the thread machining of all the intermittent threaded holes in the rack is automatically completed by adopting the hard alloy thread milling cutter through numerical control program instructions in a circular arc spiral interpolation mode, and the effects of improving the product quality and the machining efficiency are achieved.

The invention adopts the following technical scheme to solve the technical problems:

The utility model provides a thread milling cutter for processing of intermittent screw hole of diesel engine frame, intermittent screw hole link up mutual welded last steel sheet and lower steel sheet, should go up the steel sheet and have the gap down between the steel sheet, its characterized in that: the thread milling cutter comprises a cutter bar, a cutter head and a plurality of blades; the cutter head and the lower end of the cutter bar are welded into a whole, the plurality of blades are uniformly distributed on the lower end surface of the cutter head along the circumference, the centers of the interiors of the cutter bar and the cutter head are provided with cooling holes which are communicated along the axial direction, the lower end surface of the cutter head is provided with a plurality of cooling grooves, one ends of the cooling grooves are communicated with the cooling holes, the other ends of the cooling grooves are opened at the cutting edges of the blades, and chip breakers are arranged on the blades; the coolant liquid by flow in the cooling hole, process the cooling bath sprays to the cutting edge department of blade, will pass through the iron fillings that the chip breaker has changed the shape are wrapped up in and are carried the discharge to change the chip removal direction, prevent this iron fillings entering go up the gap between steel sheet and the lower steel sheet.

Further, the lower end face of the cutter head is provided with an embedded blade mounting groove, and the blade is locked and fixed in the blade mounting groove through a screw.

further, the cutting tip of the insert is oriented in the radial direction, and the positive rake angle of the insert in the radial direction is yf equal to 10 °.

Further, the cutter arbor adopt whole carbide material to make, the tool bit is made for steel, the blade is through PVD physics picture layer processing.

further, the number of the blades is 5.

Further, the blade can be used for 4 times by being installed in a positive and negative mode.

The other technical scheme of the invention is as follows:

a machining method for intermittent threaded holes of a diesel engine frame, which is realized by adopting the thread milling cutter, is characterized in that: and the thread milling cutter is adopted on a gantry milling machine, and the rough milling and the finish milling of the threads of the intermittent threaded holes are automatically finished in the intermittent threaded holes from bottom to top in a circular arc spiral interpolation mode through numerical control program instructions.

Further, the processing method comprises the following steps:

1) Placing the rack on the table top of the planer type milling machine, leveling, straightening, clamping and pressing, and setting a zero position;

2) The blades are embedded into the blade mounting grooves of the cutter heads, the blades are locked and fixed by screws, and the assembled thread milling cutter is mounted on a main shaft of the planer type milling machine;

3) and through numerical control program instructions, the rough milling and the finish milling of the threads of all the interrupted threaded holes on the rack are automatically finished from bottom to top in the interrupted threaded holes in a circular arc spiral interpolation mode.

Compared with the prior art, the invention has the beneficial effects that:

1. the radial positive rake angle yf of thread milling cutter blade is 10, and the blade is provided with the chip breaker groove, can change the iron fillings shape, and the reunion cutter arbor and the tool bit are equipped with the cooling hole and the cooling bath that run through, and the coolant liquid can spray to the cutting edge department of blade, has effectively guaranteed that cooling and chip removal are unobstructed, has changed the chip removal direction, therefore has effectively avoided iron fillings to get into the crack of two steel sheets in participate in the card sword and the mashed tooth risk that the secondary cutting leads to the processingquality and the machining efficiency of interrupted screw hole have been improved.

2. The machining method adopts the thread milling cutter to automatically finish the rough and finish milling thread machining of the interrupted thread hole from the bottom of the hole to the top in a circular arc spiral interpolation cutting mode, thereby not only ensuring automatic continuous machining, but also improving the machining quality and efficiency.

3. The cutter bar of the thread milling cutter is made of an integral hard alloy material, so that the rigidity requirement is met; each blade is subjected to physical coating treatment by PVD (physical vapor deposition), and can be positively and negatively mounted for use for 4 times, so that the consumption cost of the cutter is reduced.

drawings

Fig. 1 is a positional arrangement diagram of interrupted screw holes in a frame.

Fig. 2 is a cross-sectional view of the AT-AT of fig. 1.

Fig. 3 is a schematic view of the structure of the thread milling cutter of the present invention.

fig. 4 is a bottom view of fig. 3.

Fig. 5 is a state diagram of the process of the present invention.

FIG. 6 is a flow chart of the process of the present invention.

In the figure, 1-upper steel plate, 2-lower steel plate, 3-gap, 4-interrupted threaded hole, 5-thread milling cutter, a-cutter bar, b-cutter head, c-welding seam, d-blade, e-cooling hole, f-cooling groove.

Detailed Description

Referring to fig. 2 and 5, the intermittent threaded hole 4 penetrates through an upper steel plate 1 and a lower steel plate 2 which are welded to each other, and a gap 3 is formed between the upper steel plate 1 and the lower steel plate 2.

Referring to fig. 3 and 4, the thread milling cutter 5 is a cemented carbide tool, and includes a tool shank a, a tool bit b, and 5 cutting blades d.

referring to fig. 3, the tool bar a is made of a solid cemented carbide material to meet the rigidity requirement; the cutter bar a and the cutter head b at the lower end are welded into a whole up and down through a welding seam c, the centers of the interiors of the cutter bar a and the cutter head b are provided with cooling holes e which are through along the axial direction, the lower end face of the cutter head b is provided with a plurality of cooling grooves f, one end of each cooling groove f is communicated with the corresponding cooling hole e, and the other end of each cooling groove f is opened at the cutting edge of the corresponding blade d. Referring to fig. 4, the cutter head b is made of steel, and the front end of the cutter head b is provided with 5 embedded blade mounting grooves which are uniformly distributed along the circumference.

Referring to fig. 4, the number of the blades d is also 5, and the blades d are locked and fixed in the blade mounting grooves by screws. The cutting edge of the blade d is radial, the radial positive rake angle yf of the blade d is 10 degrees, the blade d is provided with a chip breaker, the blade d is subjected to physical pattern layer processing by PVD, and each blade d can be installed and used for 4 times in a positive and negative mode.

Cooling liquid flows out of the cooling hole e, is sprayed to the cutting edge of the blade d through the cooling groove, and wraps and discharges the scrap iron with the shape changed by the chip breaker groove, so that smooth cooling and chip removal are effectively ensured; chip-breaker on the blade d combines the coolant liquid can change iron fillings shape and chip removal direction, can prevent that iron fillings from getting into go up steel sheet 1 and lower gap 3 between the steel sheet 2 to avoid the double-layered bits in this gap 3 to participate in the card sword and the mashed tooth risk that secondary cutting and cause, improved the processingquality and the efficiency of intermittent screw hole.

Referring to fig. 5, in the method for machining the intermittent threaded hole of the diesel engine frame, a thread milling cutter 5 is adopted on a planer type milling machine, and the rough milling and the finish milling of the thread of the intermittent threaded hole 4 are automatically completed in the intermittent threaded hole 4 from bottom to top in a circular arc spiral interpolation mode through a numerical control program instruction.

Referring to fig. 6, the processing method includes the following steps:

1) The frame is placed on a milling table surface, leveled, straightened, clamped and compressed, and a zero position is set;

2) The thread milling cutter is arranged on the milling spindle, the blade is embedded in the front end of the cutter bar, and the screw is locked and fixed;

3) and (3) automatically finishing the rough and finish milling of all interrupted threaded holes on the rack from bottom to top in a circular arc spiral interpolation mode through numerical control program instructions.

In a word, the invention overcomes the defects of the traditional tap tapping method for the discontinuous threaded hole of the frame, achieves the effects of no chip clamping, smooth chip removal, no tooth decay and improved quality and efficiency of the crack in the discontinuous threaded hole, and realizes the automatic processing of efficient continuous full-program control.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. The scope of the invention as claimed should also include obvious modifications and alternatives to the present invention.