CN119281998B - A high-module spur gear forging with full teeth and its forming device - Google Patents

Abstract

The full-tooth-height oversized modulus straight gear forging comprises half-tooth-height steps and full-tooth-height steps, wherein the thickness of the half-tooth-height steps is not smaller than the height of a transitional arc between two adjacent full-tooth-height steps, tooth profile line differences between tooth profile lines of the full-tooth-height oversized modulus gear forging and tooth profile lines of an oversized modulus gear part after machining are uniform, tooth profile metal streamline of the full-tooth-height steps are continuously distributed along the tooth profile, an upper tooth-shaped punch of a forming device is connected with an upper sliding block of a press through a switching mechanism, the upper tooth-shaped punch is used for extruding metal blanks in a lower die assembly, and the preparation of the forging is realized through left-right movement of a left die assembly and a right die assembly which are symmetrically arranged in the extrusion process. The forging prepared by the method can ensure that the metal streamline is distributed along the contour of the part after machining, the metal streamline is basically free from cutting off and outcropping, the strength of the gear is well improved, and the requirements of the engineering machinery, marine equipment and aerospace equipment on high-load large-modulus gears can be met.

Description

Full-tooth-height super-large-modulus spur gear forging and forming device thereof

Technical Field

The invention relates to the technical field of gear manufacturing, in particular to a full-tooth-height ultra-large-modulus gear forging and a forming device thereof.

Background

The gear is an important part in a mechanical device, is one of basic core parts in a transmission machine, and mainly aims to transmit power and motion and change the magnitude and the direction of rotating speed and torque. Along with the development of machine tool technology, gear shaping, gear hobbing and gear grinding equipment are higher and higher in precision, and the development of gear processing technology is rapid. For gears without special use requirements, the gear can be directly processed by using blank metal and can be used after heat treatment and finish machining. For gears with special use conditions or extreme load requirements, it is necessary to form tooth-shaped metal streamlines by forging to further improve the mechanical properties of the tooth shape. For small modulus gears (m is less than or equal to 4.5) with lower tooth shapes, the small modulus gears can be directly extruded and formed by adopting a cold forging or hot forging method, blanks can be filled in a die cavity after flowing radially for a short distance, and the die service life and friction force can meet the forming requirements. The large-modulus gear (m is more than or equal to 5) with higher tooth shape is generally larger in volume, if the tooth shape is processed by adopting a hot forging forming method, the blank metal with larger volume is required to flow for a long distance to fill the cavity of the full-tooth-height die, the mechanical strength of the die is rapidly reduced due to temperature rise of the high-temperature blank and contact with the die, simultaneously, a large amount of metal rapidly flows at the tooth root of the die, the lubricant at the tooth root rapidly disappears due to a large amount of friction behaviors, the friction force is increased, the metal is difficult to flow, rapid deformation and failure at the tooth root of the die are finally caused, and the forming of the ultra-large-modulus straight gear forging with full tooth height cannot be realized. The scheme is that the half-tooth deep forging at the design position of the forging is adopted, as shown in fig. 2, the metal flowing distance of the half-tooth deep forging is reduced, the service life of a die is guaranteed, but a streamline close to the tooth root part is cut off after the forging is machined, and the aim of improving the gear performance cannot be achieved. The fields of engineering machinery, marine equipment and aerospace equipment have more and more demands on high-load oversized modulus gears (m is more than or equal to 10), and development of the oversized modulus gears meeting the demands is needed.

Disclosure of Invention

In order to overcome the defects, the invention provides the full-tooth-height super-large-modulus gear forging and the forming device thereof, which realize batch forming of full-tooth-height super-large-modulus straight gears, and metal streamline of the formed gears is distributed along the profile line of the full-tooth-height tooth shape, so that the bearing capacity of the gears is improved.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

The full-tooth-height oversized modulus straight gear forging comprises half-tooth-height steps and full-tooth-height steps, wherein the thickness of the half-tooth-height steps is not smaller than the height of a transition arc between two adjacent full-tooth-height steps, the tooth profile of the full-tooth-height oversized modulus straight gear forging of the full-tooth-height steps is uniform in difference value with the tooth profile of an oversized modulus gear part after machining, and tooth profile metal streamline of the full-tooth-height steps are continuously distributed along the tooth profile.

The utility model provides a forming device of super large modulus spur gear forging of full tooth height, includes mould subassembly, lower mould subassembly, left mould subassembly and right mould subassembly, go up the mould subassembly and be last profile of tooth drift, go up profile of tooth drift and be connected with the press upper slide block through switching mechanism, go up profile of tooth drift and be used for the extrusion metal blank in the lower mould subassembly, the preparation of forging is realized through the left and right movement of left mould subassembly and right mould subassembly that the symmetry set up in the extrusion process.

Further preferably, the lower die assembly comprises a die holder, a die cover plate, an upper tooth-shaped die, a lower tooth-shaped die, a stop pin, a lower tooth-shaped punch and a square ejector rod, wherein the lower tooth-shaped die and the upper tooth-shaped die are sequentially arranged in a circular stepped hole at the upper end of the die holder from bottom to top, a semicircular groove is formed at the periphery of the lower tooth-shaped die and the upper tooth-shaped die, the semicircular groove and the semicircular groove in the stepped hole of the die holder form a circular hole, the stop pin is inserted into the circular hole, the lower tooth-shaped punch is arranged in a die cavity of the lower tooth-shaped die, the bottom of the lower tooth-shaped punch is connected with the square ejector rod, the square ejector rod is inserted into a square hole at the lower end surface of the die holder, the die cover plate is arranged at the upper end of the upper tooth-shaped die, and the die cover plate is fixedly connected with the upper end surface of the die holder for fixing the upper tooth-shaped die.

Further preferably, the upper tooth-shaped concave die corresponds to the central axis and the semicircular groove of the lower tooth-shaped concave die, the tooth shapes of the upper tooth-shaped concave die and the lower tooth-shaped concave die correspond to each other, the square flange at the head part of the square ejector rod is connected with the square positioning groove of the lower tooth-shaped punch, the lower tooth-shaped punch passes through the lower tooth-shaped concave die, and the lower end of the square ejector rod is inserted into the square guide rod hole of the lower end face of the die holder.

Further preferably, the left die assembly comprises a left lower pulling plate, a left lower connecting plate, a left lower oil cylinder, a left upper connecting plate, a left upper oil cylinder and a left upper pulling plate, wherein the left lower pulling plate and the left upper pulling plate are inserted into rectangular holes at the left end of the die holder, rectangular grooves are formed in the middle parts of the right sides of the left upper pulling plate and the left lower pulling plate, the left side of the left upper pulling plate is connected with the left upper connecting plate, the left upper connecting plate is connected with left upper oil cylinder heads at the front end and the rear end of the left upper pulling plate, two left upper oil cylinders are fixedly mounted in left side square grooves of the die holder, rectangular grooves are formed in the middle part of the right side of the left lower pulling plate, the left side of the left lower pulling plate is connected with the left lower connecting plate, and two left lower oil cylinders are fixedly mounted in left side square grooves of the die holder.

Further preferably, the right die assembly comprises a right lower pulling plate, a right lower connecting plate, a right lower oil cylinder, a right upper connecting plate, a right upper oil cylinder and a right upper pulling plate, wherein the right upper pulling plate is inserted into a right-end rectangular groove of the die holder, a rectangular groove is formed in the middle of the left side of the right upper pulling plate, the right side of the right upper pulling plate is connected with the right upper connecting plate, the left upper connecting plate is connected with right upper oil cylinder heads at the front end and the rear end, two right upper oil cylinders are fixedly arranged in right-side rectangular grooves of the die holder, the right lower pulling plate is inserted into a right-end rectangular groove of the die holder, a rectangular groove is formed in the middle of the left side of the right lower pulling plate, the right side of the right lower pulling plate is connected with the right lower connecting plate, the right lower oil cylinder heads at the front end and the rear end are fixedly arranged in right-side direction holes of the die holder.

Further optimizing, the contour line of the metal blank is smaller than the tooth top circle of the tooth profile contour line of the upper tooth profile female die cavity of the upper tooth profile female die by delta t1, wherein delta t1 is the expansion amount of the blank after heating plus 1mm, and the contour line of the lower tooth profile female die cavity of the lower tooth profile female die is larger than the contour line of the upper tooth profile female die cavity by delta t2, wherein delta t2 is the expansion amount of the blank after demolding from the upper tooth profile female die plus 1mm.

Further optimized, the widths of the left upper pulling plate and the right upper pulling plate are larger than those of the left lower pulling plate and the right lower pulling plate, and the thicknesses of the left upper pulling plate and the right upper pulling plate are the same as the full-tooth height steps of the gear forgings.

The beneficial effects of the invention are as follows:

The forming device overcomes the problems of low die life and large forming force caused by severe blank flow in the forming process of the full-tooth-height and super-large-modulus straight gear forging, the forming process is divided into two stages, the forming process is completed by two stages of dies, the upper stage completes the forming of a blank with a certain half-tooth-height, the lower stage completes the forming of the full-tooth-height forging, the two stages of dies have lower temperature rise and good lubrication, the die deformation failure is effectively prevented, the die life is prolonged, the full-tooth-height and super-large-modulus straight gear forging can be formed in batches, and the forming device can meet the requirements of engineering machinery, marine equipment and aerospace equipment for high-load super-large-modulus gears.

Drawings

FIG. 1 is a three-dimensional view of a full tooth height oversized modulus spur gear forging of the present invention;

FIG. 2 full tooth height (full tooth depth) oversized modulus spur gear forging metal flow diagram;

FIG. 3 is a half tooth depth oversized modulus spur gear forging metal flow diagram;

FIG. 4 is a schematic drawing of a full tooth height oversized modulus spur gear forging forming process;

FIG. 5 is a three-dimensional view of a full tooth height oversized modulus spur gear forging forming device (without a die cover plate) of the invention;

FIG. 6 is a front cross-sectional view of a full tooth height oversized modulus spur gear forging forming device;

FIG. 7 is a top cross-sectional view of a full tooth height oversized modulus spur gear forging forming apparatus;

FIG. 8 is a schematic diagram of the forming device during the forming process of the full tooth height oversized modulus spur gear forging;

FIG. 9 is a schematic drawing of the demolding after the full tooth height oversized modulus spur gear forging is formed;

FIG. 10 is a graph comparing profile lines of an upper toothed female die, a lower toothed female die and a blank;

FIG. 11 is a schematic diagram showing connection of a tooth-shaped female die and a square ejector rod;

The die comprises the following components of 1, square ejector rods, 2, die holders, 3, a left lower pulling plate, 4, a left lower connecting plate, 5, a left lower oil cylinder, 6, a left upper connecting plate, 7, a left upper oil cylinder, 8, a left upper pulling plate, 9, stop pins, 10, die cover plates, 11, an upper tooth-shaped punch, 12, an upper tooth-shaped die, 13, a blank, 14, a lower tooth-shaped die, 15, a lower tooth-shaped punch, 16, a right upper connecting plate, 17, a right upper oil cylinder, 18, a right upper pulling plate, 19, a right lower oil cylinder, 20, a right lower connecting plate, 21, a right lower pulling plate, 101, a half tooth height step, 102, a full tooth height step, 103, a transition arc, 200, an ultra-large-module gear forging tooth-shaped profile line after mechanical processing, 201, 202, a half tooth depth ultra-large-module gear forging tooth-shaped profile line, 300, a forging discharge hole, 401, a lower tooth-shaped die cavity profile line, 402, an upper tooth-shaped die cavity profile line, 403 and a blank profile line.

Detailed Description

In order that the above objects, features and advantages of the present invention may be more clearly understood, a detailed description of the invention will be made with reference to the following examples, which are given by way of illustration of the technical solution of the present invention, but the present invention may be practiced otherwise than as described herein, and thus the scope of the present invention is not limited to the following examples.

The full-tooth-height super-large-modulus straight gear forging has the advantages that the modulus of the gear is 40, the number of teeth is 13, the full-tooth-height straight gear forging comprises a half-tooth-height step 101 and a full-tooth-height step 102, and counter bores are formed in two end faces according to the requirement of machining gear parts. The thickness of the half-tooth-height step 101 is not smaller than the height of the transition arc 103 of the two steps, the tooth profile line 201 of the full-tooth-height oversized modulus gear forging of the full-tooth-height step 102 is uniform in difference value (machining quantity) with the tooth profile line 200 of the oversized modulus gear part after machining, the tooth profile metal streamline of the full-tooth-height step 102 is distributed along the tooth profile, and the phenomenon of cutting off and outcrop of the streamline does not occur. The half-tooth height step 101 of the forging is required by a process, and is machined and removed completely or partially according to the drawing requirement of the gear part.

A full-tooth-height oversized-modulus spur gear forging forming device comprises an upper die assembly, a lower die assembly, a left die assembly and a right die assembly. The upper die assembly is an upper tooth-shaped punch 11, and the upper tooth-shaped punch 11 is connected with an upper sliding block of the press through a switching mechanism. The lower die assembly comprises a square ejector rod 1, a die holder 2, a stop pin 9, a die cover plate 10, an upper tooth-shaped die 12, a lower tooth-shaped die 14 and a lower tooth-shaped punch 15. The lower tooth-shaped female die 14 and the upper tooth-shaped female die 12 are sequentially arranged in a circular stepped hole at the upper end of the die holder 2, a stop pin 9 is inserted into a circular hole formed by a semicircular groove formed at the outer circle of the lower tooth-shaped female die 14 and the semicircular groove in the stepped hole of the die holder 2, a lower tooth-shaped punch 15 is arranged in a die cavity of the lower tooth-shaped female die 14, the lower tooth-shaped punch 15 is connected with the square ejector rod 1, the square ejector rod 1 is inserted into a square hole at the lower end face of the die holder 2, and a female die cover plate 10 is arranged at the upper end of the upper tooth-shaped female die 12 and fixedly connected with the upper end face of the die holder 2 to play a role in fixing the upper tooth-shaped female die 12.

The left die assembly comprises a left lower pulling plate 3, a left lower connecting plate 4, a left lower oil cylinder 5, a left upper connecting plate 6, a left upper oil cylinder 7 and a left upper pulling plate 8. The left upper pulling plate 8 is inserted into a rectangular hole at the left end of the die holder 2, a rectangular groove is formed in the middle of the right side of the left upper pulling plate 8, the left side of the left upper pulling plate 8 is connected with the left upper connecting plate 6, the left upper connecting plate 6 is connected with left upper oil cylinders 7 at the front end and the rear end, two left upper oil cylinders are fixedly arranged in a left square groove of the die holder 2, the left lower pulling plate 3 is inserted into a rectangular hole at the left end of the die holder 2, a rectangular groove is formed in the middle of the right side of the left lower pulling plate 3, the left side of the left lower pulling plate 3 is connected with the left lower connecting plate 4, the left lower connecting plate 4 is connected with left lower oil cylinders 5 at the front end and the rear end, and the two left lower oil cylinders 5 are fixedly arranged in a left square groove of the die holder 2. The right die assembly comprises a right lower pulling plate 21, a right lower connecting plate 20, a right lower oil cylinder 19, a right upper connecting plate 16, a right upper oil cylinder 17 and a right upper pulling plate 18. The right upper pulling plate 18 is inserted into a right-end rectangular groove of the die holder 2, a rectangular groove is formed in the middle of the left side of the right upper pulling plate 18, the right side of the right upper pulling plate 18 is connected with the right upper connecting plate 16, the right upper connecting plate 16 is connected with right upper oil cylinders 17 cylinder heads at the front end and the rear end, two right upper oil cylinders 17 are fixedly arranged in the right-side rectangular groove of the die holder 2, the right lower pulling plate 21 is inserted into the right-end rectangular groove of the die holder 2, a rectangular groove is formed in the middle of the left side of the right lower pulling plate 21, the right side of the right lower pulling plate 21 is connected with the right lower connecting plate 20, the right lower connecting plate 20 is connected with right lower oil cylinders 19 cylinder heads at the front end and the rear end, and the two right lower oil cylinders 19 are fixedly arranged in right direction holes of the die holder 2.

In the forming device, semicircular grooves at the outer circles of the upper tooth-shaped female die 12 and the lower tooth-shaped female die 14 have a position relationship with tooth-shaped die cavities of the upper tooth-shaped female die 12 and the lower tooth-shaped female die 14, so that the upper tooth-shaped female die and the lower tooth-shaped female die are prevented from rotating axially to cause tooth-shaped die errors. After the central axis of the upper tooth-shaped female die 12 corresponds to the central axis of the lower tooth-shaped female die 14 and the semicircular groove, the tooth shapes of the upper tooth-shaped female die 12 and the lower tooth-shaped female die 14 correspond to each other. The square flange of square ejector pin 1 head is connected with the square constant head tank of lower profile of tooth drift 15, and square ejector pin lower part inserts in the square guide arm hole of die holder 2 lower terminal surface, and square constant head tank's position should be guaranteed and can make lower profile of tooth drift 15 pass through smoothly in lower profile of tooth die 14, and this structure can guarantee square ejector pin 1 and the lower profile of tooth drift 15 of being connected with it can not take place to rotate. The square shape of the square ejector rod 1 determines the position of the lower tooth-shaped punch 15 to prevent axial rotation, and the lower tooth-shaped punch 15 and the lower tooth-shaped die 14 are separated in the forming process, so that positioning is needed during resetting to prevent the lower tooth-shaped die 14 and the lower tooth-shaped punch 15 from interfering.

In the molding device, a blank contour line 403 is smaller than a tooth top circle of a tooth profile contour of a cavity of the upper tooth-shaped female die by delta t1, and delta t1 is an expansion amount of the blank after heating and is 1mm. This structure ensures that the blank is smoothly placed into the cavity of the upper toothed die 12 without damaging the lubricant adhering to the tooth root. The lower tooth die cavity contour 401 of the lower tooth die 14 is greater than the upper tooth die cavity contour 402 of the upper tooth die 12 by Δt2, Δt2 being the expansion of the blank after ejection from the upper tooth die plus 1mm size. The structure can ensure that the blank can not contact with the die cavity of the lower tooth-shaped die after being ejected from the upper tooth-shaped die 12, so that the lubricant attached to the blank can be reserved, and the deformation behavior of the blank in the lower tooth-shaped die 14 is facilitated.

In the forming device, the widths of the left upper pulling plate 8 and the right upper pulling plate 18 are larger than those of the left lower pulling plate 3 and the right lower pulling plate 21, and the thicknesses of the left upper pulling plate 8 and the right upper pulling plate 18 are equal to the thickness of the full-tooth-height step 102 of the gear forging. In the moving process of the pulling plate, the structure ensures that the weight of the upper pulling plate is not completely born by the lower pulling plate, and part of the weight is born by the groove steps of the die holder 1, so that the pulling plate moves flexibly, and the pressure of the pulling plate cylinder is stable.

The foregoing has outlined and described the features, principles, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the above-described embodiments, and that the above-described embodiments and descriptions are merely illustrative of the principles of the present invention, and that various changes and modifications may be made in the invention without departing from the spirit and scope of the invention, which is defined by the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (4)

1. A forming device for a high-module spur gear forging, characterized in that it includes an upper die assembly, a lower die assembly, a left die assembly and a right die assembly, wherein the upper die assembly is an upper tooth-shaped punch (11), the upper tooth-shaped punch (11) is connected to the upper slide of the press through a transfer mechanism, the upper tooth-shaped punch (11) is used to extrude the metal billet (13) in the lower die assembly, and the forging is prepared by the left and right movement of the symmetrically arranged left die assembly and right die assembly during the extrusion process; The lower die assembly includes a die base (2), a die cover plate (10), an upper toothed die (12), a lower toothed die (14), a stop pin (9), a lower toothed punch (15), and a square ejector pin (1). The lower toothed die (14) and the upper toothed die (12) are installed sequentially from bottom to top in the circular stepped hole at the upper end of the die base (2). The outer periphery of the lower toothed die (14) and the upper toothed die (12) forms a semi-circular groove, which is connected to the die base (2). The semi-circular groove in the stepped hole forms a round hole. The stop pin (9) is inserted into the round hole. The lower tooth punch (15) is installed in the cavity of the lower tooth die (14). The bottom of the lower tooth punch (15) is connected to the square push rod (1). The square push rod (1) is inserted into the square hole on the lower end face of the mold base. The die cover plate (10) is installed on the upper end of the upper tooth die (12). The die cover plate (10) is fixed to the upper end face of the mold base (2) to fix the upper tooth die (12). The left mold assembly includes a lower left pull plate (3), a lower left connecting plate (4), a lower left cylinder (5), an upper left connecting plate (6), an upper left cylinder (7), and an upper left pull plate (8). The lower left pull plate (3) and the upper left pull plate (8) are inserted into the rectangular hole at the left end of the mold base (2). A rectangular groove is provided in the middle of the right side of the upper left pull plate (8) and the lower left pull plate (3). The left side of the upper left pull plate (8) is connected to the upper left connecting plate (6). The upper left connecting plate (6) is connected to the upper left connecting plate (7). The upper left cylinder (7) of the front and rear ends of the pull plate (8) is connected to the cylinder head, and the two upper left hydraulic cylinders (7) are fixedly installed in the square groove on the left side of the mold base (2); a rectangular groove is provided in the middle right side of the lower left pull plate (3), the left side of the lower left pull plate (3) is connected to the lower left connecting plate (4), the lower left connecting plate (4) is connected to the cylinder head of the lower left cylinder (5) at the front and rear ends of the lower left pull plate (3), and the two lower left hydraulic cylinders (5) are fixedly installed in the square groove on the left side of the mold base (2); The blank outline (403) of the metal blank (13) is △t1 smaller than the tooth tip circle of the tooth outline (402) of the upper toothed die cavity of the upper toothed die (12), where △t1 is the amount of expansion of the blank after heating plus 1mm; the lower toothed die cavity outline (401) of the lower toothed die (14) is △t2 larger than the upper toothed die cavity outline (402), where △t2 is the amount of expansion of the blank after exiting the upper toothed die plus 1mm; The forging of a full-tooth high-module spur gear prepared by the forming device includes a half-tooth high step (101) and a full-tooth high step (102). The thickness of the half-tooth high step (101) is not less than the height of the transition arc (103) between two adjacent full-tooth high steps (102). The tooth profile (201) of the full-tooth high step (102) of the forging of the full-tooth high-module spur gear has a uniform difference from the tooth profile (200) of the machined high-module gear part. The tooth profile metal flow lines of the full-tooth high step (102) are continuously distributed along the tooth profile. 2. The forming device for a full-tooth high-module spur gear forging as described in claim 1, characterized in that the central axis and semi-circular groove of the upper tooth-shaped die (12) and the lower tooth-shaped die (14) correspond to each other, the tooth shape of the upper tooth-shaped die (12) and the lower tooth-shaped die (14) correspond to each other, the square flange at the head of the square push rod (1) is connected to the square positioning groove of the lower tooth-shaped punch (15), the lower tooth-shaped punch (15) passes through the lower tooth-shaped die (14), and the lower end of the square push rod (1) is inserted into the square guide rod hole on the lower end face of the die base (2). 3. The forming device for a full-tooth high-module spur gear forging as described in claim 1, characterized in that the right mold assembly includes a right lower pull plate (21), a right lower connecting plate (20), a right lower cylinder (19), a right upper connecting plate (16), a right upper cylinder (17), and a right upper pull plate (18). The right upper pull plate (18) is inserted into the right end rectangular groove of the mold base (2). A rectangular groove is provided in the middle of the left side of the right upper pull plate (18). The right side of the right upper pull plate (18) is connected to the right upper connecting plate (16). (16) Connect to the cylinder head of the upper right cylinder (17) at both ends. The two upper right cylinders (17) are installed and fixed in the square groove on the right side of the mold base (2). The lower right pull plate (21) is inserted into the rectangular groove on the right end of the mold base (2). A rectangular groove is set in the middle of the left side of the lower right pull plate (21). The right side of the lower right pull plate (21) is connected to the lower right connecting plate (20). The lower right connecting plate (20) is connected to the cylinder head of the lower right cylinder (19) at both ends. The two lower right cylinders (19) are installed and fixed in the direction hole on the right side of the mold base (2). 4. The forming device for a high-module spur gear forging as described in claim 3, characterized in that the width of the upper left pull plate (8) and the upper right pull plate (18) is greater than the width of the lower left pull plate (3) and the lower right pull plate (21), and the thickness of the upper left pull plate (8) and the upper right pull plate (18) is the same as the high-module step (102) of the gear forging.