阅读说明：本技术 一种变螺距螺钉的运算加工方法 (Calculation machining method for variable-pitch screw ) 是由 姚力军 张桐滨 周文 程忠飞 张亚飞 何思斌 于 2021-07-19 设计创作，主要内容包括：本发明提供了一种变螺距螺钉的运算加工方法,所述的运算加工方法包括如下步骤：(Ⅰ)根据变螺距螺钉的设计要求,对初始参数进行宏变量赋值；(Ⅱ)根据宏变量赋值计算加工变量,基于加工变量编制车削加工宏程序并输入至车削机床中；(Ⅲ)车削机床对原料坯分段加工出变螺距螺纹,得到所述的变螺距螺钉。本发明提供的变螺距螺钉自动运算加工方法,将有效解决数控编程人员工作量,经过数控编程人员对程序校验和现场一个规格调试后,可正常批量量产,中途改变规格时无需另外编程及调试,从而提升产品质量及生产效率。(The invention provides an arithmetic processing method of a variable-pitch screw, which comprises the following steps: carrying out macro variable assignment on initial parameters according to the design requirements of the variable-pitch screw; (II) calculating a machining variable according to the macro variable assignment, and compiling a turning macro program based on the machining variable and inputting the turning macro program into a turning machine tool; (III) machining the variable-pitch thread on the raw material blank by the turning machine tool in a segmented manner to obtain the variable-pitch screw. The automatic operation processing method for the variable-pitch screw, provided by the invention, can effectively solve the workload of numerical control programmers, can realize normal batch volume production after program verification and field specification debugging of the numerical control programmers, and does not need additional programming and debugging when the specification is changed midway, thereby improving the product quality and the production efficiency.)

1. The calculation processing method of the variable-pitch screw is characterized by comprising the following steps of:

carrying out macro variable assignment on initial parameters according to the design requirements of the variable-pitch screw;

(II) calculating a machining variable according to the macro variable assignment, and compiling a turning macro program based on the machining variable and inputting the turning macro program into a turning machine tool;

(III) machining the variable-pitch thread on the raw material blank by the turning machine tool in a segmented manner to obtain the variable-pitch screw.

2. The arithmetic processing method according to claim 1, wherein the variable-pitch screw comprises a body, the body is composed of a cone and a cylinder which are sequentially butted, the butted surface of the cone and the cylinder is a boundary ring surface, the outer surface of the body is turned from the head end surface to the tail end surface in a segmented manner, and a variable-pitch thread is formed by processing.

3. The arithmetic processing method according to claim 2, wherein the variable-pitch thread formed by processing the outer periphery of the cone is divided into a first thread section and a second thread section from a head end surface to a tail end surface;

the thread tooth tops of the first thread sections are positioned on the same cylindrical surface, and the thread tooth heights of the first thread sections are the same;

the variable-pitch thread formed by processing the periphery of the cylinder is divided into a third thread section, a fourth thread section and a fifth thread section from the end surface of the head part to the end surface of the tail part;

the thread tooth heights of the third thread sections are the same; the thread tooth tops of the fourth thread sections are positioned on the same conical surface, the small end of the conical surface is positioned on the third thread section, and the large end of the conical surface is positioned on the fifth thread section; the thread tooth heights of the fifth thread sections are the same and are all higher than those of the third thread sections.

4. The arithmetic processing method according to any one of claims 1 to 3, wherein in step (I), the initial parameters to be assigned to the macro variables include total length L, head pitch P₁Tail pitch P₂The distance D between the end face of the head and the intersected ring surface, the width Z of a single thread tooth and the width U of a cutter.

5. The arithmetic processing method of any one of claims 1 to 4, wherein in step (II), the processing variables calculated based on the macro variable assignments comprise: the total number of turns Q of the thread, the gradual change B of the thread pitch, the thread pitch delta P at the junction ring surface, the number of turns S of the thread at the junction ring surface, the total length W of the thread at the junction ring surface and the thread processing position N of the end surface of the head part₀Thread start machining tooth K_xStarting pitch P of each thread_xInitial machining position N of each section of thread_xThe number of processed teeth of each section of thread is delta K, and the end face of the head part reaches one section of thread knotDistance L of beam spot_xAnd a tool width H;

thread machining position N of head end face₀The method is characterized in that when a first thread section is machined, the cutter feeding position of a cutter is turned;

after the processing of each thread section is finished, calling the macro program, and recalculating the initial processing tooth K of the next thread section_xStarting pitch P of the next thread_xAnd the initial machining position N of the next section of thread_x；

Preferably, the number of processed teeth Δ K of each thread segment is 5.

6. The arithmetic processing method according to any one of claims 1 to 5, wherein the total number of turns Q of the thread is calculated according to the formula (1):

wherein, FUP refers to rounding up the calculation result;

preferably, the gradient B of the pitch per revolution is calculated according to equation (2):

7. the arithmetic processing method according to any one of claims 1 to 6, wherein a pitch Δ P at the boundary ring surface is calculated according to the formula (3):

preferably, the number of turns S of the thread at the interface annulus is calculated according to equation (4):

preferably, the total thread length W at the interface annulus is calculated according to equation (5):

8. the arithmetic processing method according to any one of claims 1 to 7, wherein the screw head processing position N is set to₀Calculated according to equation (6):

N₀L-D-W formula (6);

preferably, the starting pitch P of each thread segment_xCalculated according to equation (7):

wherein, when turning the first thread section, K_xTaking 1; then, before each section of thread is turned, a macro program is called, and the thread initial machining tooth K is recalculated according to the formula (8)_x：

K_x＝K_x-1+. DELTA.K-1 formula (8);

wherein, K_x-1Representing the initial processing tooth of the previous thread of the x section;

preferably, the starting machining position N of each thread segment_xCalculated according to equation (9):

9. the arithmetic processing method according to any one of claims 1 to 8, wherein a distance L from the end face to an end point of one of the threads_xCalculated according to equation (10):

preferably, the thread ridge width H is calculated according to equation (11):

H＝P_x-Z-U formula (11).

10. The arithmetic processing method according to any one of claims 1 to 9, wherein the step (iii) specifically includes the steps of:

(1) under the control of the macroprogram, the turning tool is processed from the screw head machining position N₀Feeding according to a set head pitch P₁Processing the initial thread of the first thread section, and then stopping processing after finishing the thread quantity of the thread quantity delta K according to the gradual change quantity B of each circle of thread pitch to obtain the first thread section;

(2) calling a macroprogram to recalculate the initial processing teeth K of the second thread section_xAnd according to K_xRecalculating the starting pitch P of the second thread segments_xAnd a starting machining position N of the second thread_xTurning tool consisting of N_xFeeding in accordance with P_xProcessing the initial thread of the second thread section, and then stopping processing after the thread quantity of the thread quantity delta K is processed according to the gradual change quantity B of each circle of thread pitch to obtain the second thread section;

(3) repeating the step (2), and sequentially processing to form a third thread section, a fourth thread section and a fifth thread section to obtain the variable-pitch screw;

in the turning process, when the workpiece is turned to the boundary ring surface, turning is carried out according to the thread pitch delta P of the boundary ring surface, the number S of turns of the thread at the boundary ring surface and the total length W of the number of turns of the thread at the boundary ring surface.

Technical Field

The invention belongs to the technical field of screw machining, and relates to an operation machining method for a variable-pitch screw.

Background

At present, the general full-thread screw and the half-thread compression screw are used for treating fractures (carpal four-bone fusion, capitate bone, lunate joint fixation, proximal radial joint fusion, fracture of the head of the radius, tuberosity fracture, fracture of the tibial plateau, fracture of the large joint, wound laceration and the like). Various specifications of screws have been in constant renewal and development for decades, but each screw has its own advantages and disadvantages, for example, a half-thread compression screw can be used for compression at the site of a fractured bone in a joint, but it has a limited range of use, and particularly, after the fractured bone is compounded, the screw is difficult to remove. The full-thread screw is easy to take out after fracture reduction, but has a narrow application range, so that the full-thread screw is prevented from being clinically applied.

For example, CN202490012U discloses a progressive continuous variable pitch screw, which comprises a screw head, a screw body and a screw tail, wherein the screw is hollow, full threads are formed from the screw head to the screw tail, the screw pitch is from small to large, the screw head or the screw head without the screw head and the screw tail are respectively and uniformly distributed with cutting grooves along the circumference, and the screw tail is spherical.

At present, the mode of processing the variable-pitch screw in the field of medical instruments is mostly to adopt an automatic lathe (a core-moving machine), but because the specification and the length of the variable-pitch screw are various, the intelligent degree of programming software on the market is not high at present, the workload of numerical control processing programmers is large, the debugging of the production workshop is frequent, the error probability is greatly improved, and the product quality control and the production efficiency are not facilitated. Huge workload is brought to numerical control programmers, and meanwhile higher requirements are also put forward to the level of the numerical control programmers.

At present, when the variable-pitch screw is programmed, the screws with different length specifications are required to be programmed, so that huge workload is brought to programming personnel, the programming error probability is high, and the field debugging and modification are not facilitated.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide the operation processing method of the variable-pitch screw, which greatly reduces the workload of numerical control programmers, can realize normal batch production after the numerical control programmers verify programs and debug one specification on site, and does not need additional programming and debugging when changing the specification midway, thereby improving the product quality and the production efficiency.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the present invention provides a method for machining a variable pitch screw, the method comprising the steps of:

carrying out macro variable assignment on initial parameters according to the design requirements of the variable-pitch screw;

(II) calculating a machining variable according to the macro variable assignment, and compiling a turning macro program based on the machining variable and inputting the turning macro program into a turning machine tool;

(III) machining the variable-pitch thread on the raw material blank by the turning machine tool in a segmented manner to obtain the variable-pitch screw.

The invention provides an operation processing method of a variable pitch screw, which is characterized in that a macro program comprising a processing program section of all elements in a raw material blank is compiled to carry out mass production processing of the variable pitch screw, so that the macro program can process raw material blanks with different shapes and different sizes to obtain the variable pitch screw, a large amount of time occupied by re-developing the program when the shapes of the raw material blanks are changed is reduced, the possibility that the response speed of a machine tool and a wrong program are influenced by the occupation of a system memory by multiple programs is avoided, the workload of numerical control programmers is greatly reduced, after program verification and field specification debugging of the numerical control programmers, normal batch mass production can be carried out, and additional programming and debugging are not needed when the specification is changed midway, thereby improving the product quality and the production efficiency.

As a preferred technical scheme of the invention, the variable-pitch screw comprises a body, wherein the body consists of a cone and a cylinder which are sequentially butted, the butted surface of the cone and the cylinder is a boundary ring surface, and the outer surface of the body is turned from the head end surface to the tail end surface in a segmented manner to form a variable-pitch thread.

As a preferred technical solution of the present invention, the variable pitch thread formed by processing the outer circumference of the cone is divided into a first thread section and a second thread section from the head end surface to the tail end surface.

The thread tooth tops of the first thread sections are located on the same cylindrical surface, and the thread tooth heights of the first thread sections are the same.

The variable-pitch thread formed by processing the periphery of the cylinder is divided into a third thread section, a fourth thread section and a fifth thread section from the end surface of the head part to the end surface of the tail part.

The thread tooth heights of the third thread sections are the same; the thread tooth tops of the fourth thread sections are positioned on the same conical surface, the small end of the conical surface is positioned on the third thread section, and the large end of the conical surface is positioned on the fifth thread section; the thread tooth heights of the fifth thread sections are the same and are all higher than those of the third thread sections.

In a preferred technical scheme of the invention, in the step (I), the processing variables needing to be subjected to macro variable assignment comprise the total length L and the head pitch P₁Tail pitch P₂The distance D between the end face of the head and the intersected ring surface, the width Z of a single thread tooth and the width U of a cutter.

As a preferred technical solution of the present invention, in the step (ii), the process variables calculated according to the assignment of the macro variables include: the total number of turns Q of the thread, the gradual change B of the thread pitch, the thread pitch delta P at the junction ring surface, the number of turns S of the thread at the junction ring surface, the total length W of the thread at the junction ring surface and the thread processing position N of the end surface of the head part₀Thread start machining tooth K_xStarting pitch P of each thread_xInitial machining position N of each section of thread_xThe number of teeth processed per thread is delta K, and the distance L from the end face of the head to the end point of one of the threads_xAnd a tool width H.

Thread machining position N of head end face₀The method refers to the tool feeding position of a turning tool when the first thread section is machined.

After the processing of each thread section is finished, calling the macro program, and recalculating the initial processing tooth K of the next thread section_xStarting pitch P of the next thread_xAnd the initial machining position N of the next section of thread_x。

Preferably, the number of processed teeth Δ K of each thread segment is 5.

As a preferred technical solution of the present invention, the total number of turns Q of the thread is calculated according to the formula (1):

FUP refers to rounding up the calculation result.

Preferably, the gradient B of the pitch per revolution is calculated according to equation (2):

as a preferred technical solution of the present invention, a pitch Δ P at the boundary ring surface is calculated according to formula (3):

preferably, the number of turns S of the thread at the interface annulus is calculated according to equation (4):

preferably, the total thread length W at the interface annulus is calculated according to equation (5):

as a preferable technical scheme of the invention, the screw head processing position N₀Calculated according to equation (6):

N₀L-D-W formula (6).

Preferably, the starting pitch P of each thread segment_xCalculated according to equation (7):

wherein, when turning the first thread section, K_xTaking 1; then, before each section of thread is turned, a macro program is called, and the thread initial machining tooth K is recalculated according to the formula (8)_x：

K_x＝K_x-1+. DELTA.K-1 formula (8).

Wherein, K_x-1Representing the initial processing tooth of the previous thread of the x section;

preferably, the starting machining position N of each thread segment_xCalculated according to equation (9):

as a preferred technical scheme of the invention, the distance L from the end face to the end point of one section of the thread_xCalculated according to equation (10):

preferably, the thread ridge width H is calculated according to equation (11):

H＝P_x-Z-U formula (11).

As a preferred technical solution of the present invention, the step (iii) specifically comprises the steps of:

(1) under the control of the macroprogram, the turning tool is processed from the screw head machining position N₀Feeding according to a set head pitch P₁Processing the initial thread of the first thread section, then completely processing the first thread section according to the gradual change B of each circle of thread pitch, and stopping after finishing processing the thread quantity of the thread quantity delta K;

(2) calling a macroprogram to recalculate the initial processing teeth K of the second thread section_xAnd according to K_xRecalculating the starting pitch P of the second thread segments_xAnd the starting processing position N of the second thread section_xTurning tool consisting of N_xFeeding in accordance with P_xProcessing the initial thread of the second thread section, then completely processing the second thread section according to the gradual change B of each circle of thread pitch, and stopping after finishing processing the number of the threads with the thread number delta K;

(3) repeating the step (2), and sequentially processing to form a third thread section, a fourth thread section and a fifth thread section to obtain the variable-pitch screw;

in the turning process, when the workpiece is turned to the boundary ring surface, turning is carried out according to the thread pitch delta P of the boundary ring surface, the number S of turns of the thread at the boundary ring surface and the total length W of the number of turns of the thread at the boundary ring surface.

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

the invention provides an operation processing method of a variable pitch screw, which is characterized in that a macro program comprising a processing program section of all elements in a raw material blank is compiled to carry out mass production processing of the variable pitch screw, so that the macro program can process raw material blanks with different shapes and different sizes to obtain the variable pitch screw, a large amount of time occupied by re-developing the program when the shapes of the raw material blanks are changed is reduced, the possibility that the response speed of a machine tool and a wrong program are influenced by the occupation of a system memory by multiple programs is avoided, the workload of numerical control programmers is greatly reduced, after program verification and field specification debugging of the numerical control programmers, normal batch mass production can be carried out, and additional programming and debugging are not needed when the specification is changed midway, thereby improving the product quality and the production efficiency.

Drawings

Fig. 1 is a schematic structural diagram of a variable pitch screw according to an embodiment of the present invention.

Wherein, 1-cone; 2-a column; 3-a first thread segment; 4-a second thread segment; 5-a third thread segment; 6-a fourth thread segment; 7-a fifth thread segment; 8-interfacing annulus.

Detailed Description

It is to be understood that in the description of the present invention, the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be taken as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

It should be noted that, in the description of the present invention, unless otherwise explicitly specified or limited, the terms "disposed," "connected" and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

In a specific embodiment, the invention provides a variable-pitch screw, as shown in fig. 1, which comprises a body, wherein the body is composed of a cone 1 and a cylinder 2 which are butted in sequence, the butted surface of the cone 1 and the cylinder is marked as a boundary ring surface 8, the outer surface of the body is turned from the head end surface to the tail end surface in a segmented manner, and a variable-pitch thread is formed by machining.

The variable-pitch thread formed by processing the periphery of the cone 1 is divided into a first thread section 3 and a second thread section 4 from the end surface of the head part to the end surface of the tail part. The thread tooth tops of the first thread sections 3 are positioned on the same cylindrical surface, and the thread tooth heights of the second thread sections 4 are the same. The variable-pitch thread formed by processing the outer periphery of the cylinder 2 is divided into a third thread section 5, a fourth thread section 6 and a fifth thread section 7 from the end surface of the head part to the end surface of the tail part. The thread tooth heights of the third thread sections 5 are the same; the thread tooth tops of the fourth thread sections 6 are positioned on the same conical surface, the small end of the conical surface is positioned on the third thread sections 5, and the large end of the conical surface is positioned on the fifth thread sections 7; the thread heights of the fifth thread segments 7 are the same and are all higher than the thread heights of the third thread segments 5.

It should be noted that, the proportional relationship between the body and the thread in fig. 1 is incorrect, and actually, the thread size on the outer periphery of the body is small and dense, which is far from the size relationship shown in the figure, and the figure is only used for assisting understanding of the position relationship of each thread section, and does not bring the proportional relationship in size.

In an embodiment, the invention provides a calculation processing method of the variable pitch screw, the calculation processing method including the steps of:

s1, carrying out macro variable assignment on the initial parameters according to the design requirements of the variable-pitch screws; the processing variables needing to be subjected to macro variable assignment comprise the total length L and the head thread pitch P₁Tail pitch P₂The distance D between the end face of the head and the boundary ring surface 8, the width Z of a single thread tooth and the width U of a cutter are required to be input into a machine tool program in advance by an operator before formal machining is started;

s2, calculating the processing variables according to the macro variable assignment, including: the total number of turns Q of the thread, the gradual change B of the thread pitch, the thread pitch delta P at the junction ring surface 8, the number of turns S of the thread at the junction ring surface 8, the total length W of the thread at the junction ring surface 8 and the thread processing position N of the end surface of the head part₀Thread start machining tooth K_xStarting pitch P of each thread_xInitial machining position N of each section of thread_xThe number of teeth processed per thread is delta K, and the distance L from the end face of the head to the end point of one of the threads_xAnd the width H of the cutter, and the calculation formula of each processing variable is as follows:

the total number of turns Q of the thread is calculated according to equation (1):

FUP refers to rounding up the calculation result.

Preferably, the gradient B of the pitch per revolution is calculated according to equation (2):

as a preferred technical solution of the present invention, the pitch Δ P at the boundary ring surface 8 is calculated according to the formula (3):

preferably, the number of turns S of the thread at the interface annulus 8 is calculated according to equation (4):

preferably, the total length W of the number of turns of the thread at the interface annulus 8 is calculated according to equation (5):

as a preferable technical scheme of the invention, the screw head processing position N₀Calculated according to equation (6):

N₀L-D-W formula (6).

Preferably, the starting pitch P of each thread segment_xCalculated according to equation (7):

wherein, when turning the first thread section, K_xTaking 1; then, before each section of thread is turned, a macro program is called to recalculate the thread initial machining tooth K according to the formula (8)_x：

K_x＝K_x-1+. DELTA.K-1 formula (8).

Wherein, K_x-1Representing the initial processing tooth of the previous thread of the x section;

preferably, the starting machining position N of each thread segment_xCalculated according to equation (9):

as a preferred technical scheme of the invention, the distance L from the end face to the end point of one section of the thread_xCalculated according to equation (10):

preferably, the thread ridge width H is calculated according to equation (11):

H＝P_x-Z-U formula (11).

S3, compiling a turning macro program based on the machining variables and inputting the turning macro program into a turning machine tool, wherein the specific turning macro program is shown in a table 1, and it should be noted that the invention only intercepts part of the main program contents due to more complete macro program contents;

s4, under the control of the macro program, the turning tool is processed from the screw head part processing position N₀Feeding and processing the first thread section according to the set thread pitch P of the head part₁Processing the initial thread of the first thread section, then processing the first thread section according to the gradual change B of the thread pitch of each circle, and stopping after finishing processing the thread quantity of the thread quantity delta K;

s5, calling the macro program to recalculate the initial processing tooth K of the second thread section_xAnd according to K_xRecalculating the starting pitch P of the second thread segments_xAnd the starting processing position N of the second thread section_xTurning tool consisting of N_xFeeding in accordance with P_xProcessing the initial thread of the second thread section, then processing the second thread section according to the gradual change B of each circle of thread pitch, and stopping after finishing processing the number of the threads with the thread number delta K;

s6, repeating the step S5, and sequentially processing to form a third thread section, a fourth thread section and a fifth thread section to obtain the variable-pitch screw;

in the turning process, when the workpiece is turned to the boundary ring surface 8, the turning processing is carried out according to the thread pitch delta P at the boundary ring surface 8, the thread turn number S at the boundary ring surface 8 and the total length W of the thread turn number at the boundary ring surface 8.

TABLE 1

The applicant declares that the above description is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and it should be understood by those skilled in the art that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are within the scope and disclosure of the present invention.