JP2567779B2 - Track ring processing method for caterpillar by general-purpose press - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a track ring processing method for tracks using a general-purpose press.

[0002]

Track rings used for caterpillars are processed by hot forging. A semi-processed product is obtained by heat treatment using the residual heat immediately after hot forging, and after induction-quenching at a specified location of this semi-processed product, drilling, roughening and cutting are performed. There is. This is because when the heat treatment after each of the above-mentioned processes is performed, the accuracy of the drilling process and the cutting process is deteriorated due to thermal strain.

[0003]

However, the machining after heat treatment has a problem that the life of the cutting tool is remarkably shortened, and the boring machine and the large-sized drilling machine are used for drilling and boring, which results in poor productivity. There is a problem. The present invention has been made to solve the above-mentioned problems, and is intended to improve productivity by sequentially performing punching and the like on a semi-processed product after heat treatment by a general-purpose press machine. An object of the present invention is to provide a track ring processing method for a caterpillar by a machine.

[0004]

[Means for Solving the Problems] As a concrete means for solving the above-mentioned problems, the outer periphery of a semi-finished product obtained by hot forging is prepared hole machining and shape machining leaving a cutting allowance for a post process. There is provided a track ring processing method characterized in that trimming and drilling, broaching at a predetermined location, and lateral drilling at a predetermined location are sequentially performed by a general-purpose press.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. The track ring for the caterpillar is, as shown in FIG. 1, a material cutting process A → heat treatment process B → hot forging process C →
It is manufactured by the heat treatment step D → cold press working step E → broaching step F → lateral hole working step G → induction hardening step H → total sizing step I.

In the material cutting step A, round bar rope or flat bar material is cut into a predetermined size. Then heat treatment step B
The material cut by is heated to about 800 ° C. In the hot forging step C, the lower die 21 provided with two punches 22 and 23 as shown in FIG. 2 is used for the pilot hole processing, the counterbore processing and the rough shape processing by crushing the material. Do it. By this hot forging process C, the stepped prepared hole 24
Then, the blank 2 having the pilot hole 25 and two rectangular pilot holes 26, 26 formed between the pilot holes 24, 25 is manufactured (FIG. 3). The prepared holes 24, 25, and 26 are provided with a withdrawal allowance for cold pressing in a subsequent process. This withdrawal allowance is about 0.1 to 1 mm for a material thickness of about 10 to 30 mm.

The semi-finished product 2 that has undergone the hot forging step C is heated to about 500 ° C. in the heat treatment step D to be heat treated. In the subsequent cold press working step E, 300
The semi-finished product 2 whose temperature has been lowered to about 0 ° C. is subjected to drilling and contour trimming using a general-purpose press.
At this time, the above-mentioned punching allowance is set in the prepared holes 24, 25 and 26, and each punch to be punched further has an R chamfered portion of about 0.5 to 5R or a material thickness of 1 to 1R. A taper of about 5% is formed.

This suppresses the formation of burrs in the holes of the holes 34, 35 and 36, eliminates the generation of cracks and fracture surfaces in the drilled portion, and shears the surface roughness of about 6-s to 3-s. Faces can be generated. At the same time as the drilling process, the flash 2a on the outer periphery of the processed product 2 is trimmed to form the track ring 3. To set the clearance between each punch diameter used for punching and the hole diameter of the female die,
For example, if the material thickness is 20 mm, the punch diameter is 30.08 mm,
When the hole diameter of the female die is 31.03 mm, the hole diameter punched out is 30.00 to 30.05 mm.

In the broaching step F, the contact surfaces 37, 37 on the outer periphery of the track ring 3 and the portions 36a, 36a corresponding to the contact surfaces 37, 37 of the hole walls of the holes 36, 36, respectively.
Broaching is performed to smooth the surface. The broaches 41a and 41b are shorter than the normal broaches because of the press stroke. Then, the cutting blade 43 following the guide portion 42 is formed to have a length which is 1 to 3 times the plate thickness of the track ring 3. The broaches 41a and 41b are attached to the punch holder 44 of the press machine as shown in FIG.
The track ring 3 set in the female die 45 is moved downward by the punch holder 44 and by the cutting blades 43 of the broaches 41a and 41b, the contact surfaces 37 and 37 and the hole wall 36.
Broaching is performed to scrape away parts a and 36a, and a smooth surface is ground.

In the lateral hole machining step G, lateral holes 51, 51 for inserting a connecting bolt into the holes 36, 36 from the contact surfaces 37, 37 of the track ring 3 are machined (FIG. 6). When the cam member 52 attached to the punch holder of the press machine descends, a cam member 53 that is horizontally moved by being pressed by the inclined cam 52a of the cam member 52 is arranged in the lower mold 54. A pair of hole punches 55 are fixed to the tip of the cam member 53, and the lateral holes 51, 51 are formed in the track ring 3 set in the lower mold 54. An R chamfered portion or a tapered portion is formed at the tip of the punching punch 55, and a sheared surface is generated at the punched portion of the lateral holes 51, 51, and burrs or the like are not generated.

Hereinafter, in the induction hardening step H, the contact surfaces 37, 37 of the track ring 3 are induction hardened, and in the final total sizing step I, upper and lower molds (not shown) are Press and use to satisfy the desired product accuracy. Further, by shot blasting, burrs, burrs and the like generated during trimming of the outer shape and broaching are removed to complete the entire processing. The semi-finished product 2 and the track ring 3 are conveyed between the respective steps by an automatic conveyance mechanism or a conveyance robot.

[0012]

As described above, according to the present invention, the track ring for the caterpillar is machined by a general-purpose press machine. Compared with the processing method using a boring machine or a large-sized drilling machine, the productivity can be improved, and the cost of the track ring can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic process drawing.

FIG. 2 is a cross-sectional view of a lower die for a hot forging step and a semi-finished product forged by the lower die.

FIG. 3 is a plan view of a semi-processed product.

FIG. 4 is a plan view of a track ring.

FIG. 5 is a schematic sectional view of a press in a broaching process.

FIG. 6 is a plan view of a track ring having a lateral hole.

FIG. 7 is a schematic cross-sectional view of a press in a horizontal hole processing step.

[Explanation of symbols]

2 ... semi-finished product, 3 ... track ring, 24,25,
26 ... Prepared hole, 34, 35, 36 ... Hole, 41a, 41
b ... Brooch, 51, 51 ... Horizontal hole, 55 ... Hole punch, C ... Hot forging process, E ... Cold press working process, F ... Brooch working process, G ... horizontal hole machining process.

Claims (1)

(57) [Claims] 1. Outer peripheral trimming and hole drilling for a semi-finished product, which has been prepared by hot forging, including pre-drilling and shaping that leaves a removal allowance for a post-process, broaching to be applied at predetermined locations, and the predetermined A track ring processing method for caterpillars, which is characterized by sequentially performing horizontal drilling on a location by a general-purpose press.