CN113843418A

CN113843418A - Forming process of automobile transmission signal wheel

Info

Publication number: CN113843418A
Application number: CN202111148300.0A
Authority: CN
Inventors: 刘明; 宋炜; 王天琪; 于景业; 邱永华
Original assignee: Shanghai Automobile Gear Works
Current assignee: Shanghai Automobile Gear Works
Priority date: 2021-09-28
Filing date: 2021-09-28
Publication date: 2021-12-28

Abstract

The invention discloses a molding process of an automobile transmission signal wheel, which comprises the following steps: providing a raw material powder; pressing the raw material powder to obtain a blank; and sintering and hardening the blank to obtain the automobile transmission signal wheel. According to the forming process of the automobile transmission signal wheel, the raw material powder is used as the material, milling is not needed after the automobile transmission signal wheel is formed, and the material utilization rate is high; in addition, the process is less, which is beneficial to reducing the production cost and improving the production efficiency.

Description

Forming process of automobile transmission signal wheel

Technical Field

The invention relates to the technical field of production of signal wheels of automobile transmissions, in particular to a forming process of the signal wheels of the automobile transmissions.

Background

The automobile transmission signal wheel is used in an automobile transmission and plays a role in signal acquisition. At present, the main forming process of the automobile transmission signal wheel is that a steel pipe is formed by milling after heat treatment, and the problems of low material utilization rate, low processing efficiency and high processing cost exist due to the adoption of a milling material reduction mode.

Disclosure of Invention

The invention mainly aims to provide a forming process of an automobile transmission signal wheel, and aims to solve the problems of low material utilization rate, low processing efficiency and high processing cost of the existing forming process.

In order to achieve the purpose, the invention provides a forming process of an automobile transmission signal wheel, which comprises the following steps:

providing a raw material powder;

pressing the raw material powder to obtain a blank;

and sintering and hardening the blank to obtain the automobile transmission signal wheel.

Optionally, the raw material powder comprises the following components in percentage by weight:

0.5-0.8% of C, 1.6-2.4% of Cu, 3.6-4.4% of Ni, 1.3-1.7% of Mo, less than 2% of impurities and the balance of Fe.

Optionally, the step of compacting the raw material powder to obtain a blank includes:

weighing 42-44 g of the raw material powder in proportion, and carrying out blank pressing on the raw material powder to obtain a blank.

Optionally, in the step of compacting the raw material powder to obtain a blank, the compacting speed is 8-12 s/piece.

Optionally, the blank obtained by compacting the raw material powder includes:

and carrying out green pressing on the raw material powder to obtain a blank, carrying out pressure monitoring during green pressing, and removing the blank of which the monitoring value is inconsistent with a preset pressure value.

Optionally, after the step of compacting the raw material powder to obtain a blank, and before the step of sintering and hardening the blank to obtain the automotive transmission signal wheel, the method further includes:

and carrying out weight detection on the blank, and rejecting the blank with a detection value inconsistent with a preset weight value.

Optionally, the step of sintering and hardening the blank to obtain the automobile transmission signal wheel comprises the following steps:

and preheating, sintering and rapidly cooling the blank in sequence to obtain the automobile transmission signal wheel.

Optionally, the step of sequentially preheating, sintering and rapidly cooling the blank to obtain the automobile transmission signal wheel is performed in a mixed gas of nitrogen and ammonia.

Optionally, the preheating temperature is 535-565 ℃; and/or the presence of a gas in the gas,

the rapid cooling speed is 2-3 ℃/s; and/or the presence of a gas in the gas,

the sintering temperature is 1110-1130 ℃; and/or the presence of a gas in the gas,

the sintering time is 25-35 min.

Optionally, after the step of sintering and hardening the blank to obtain the signal wheel of the automobile transmission, the method further comprises the following steps:

removing burrs of the automobile transmission signal wheel;

and cleaning the automobile transmission signal wheel after deburring.

According to the technical scheme, the raw material powder is used as the material, milling is not needed after the automobile transmission signal wheel is formed, and the material utilization rate is high; in addition, the process is less, which is beneficial to reducing the production cost and improving the production efficiency.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other related drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic flow chart of a first embodiment of a process for forming a signal wheel of an automotive transmission according to the present invention;

FIG. 2 is a schematic flow chart of a second embodiment of the molding process for the signal wheel of the transmission of the automobile according to the present invention;

fig. 3 is a schematic flow chart of a third embodiment of the forming process of the signal wheel of the automobile transmission provided by the invention.

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that, if directional indications (such as up, down, left, right, front, and back … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative positional relationship between the components, the movement situation, and the like in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is 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" or "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" appearing throughout includes three juxtapositions, exemplified by "A and/or B" including either A or B or both A and B. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

In view of the above, the invention provides a molding process of an automobile transmission signal wheel, which takes raw material powder as a material, does not need milling after the automobile transmission signal wheel is molded, and has high material utilization rate; in addition, the process is less, which is beneficial to reducing the production cost and improving the production efficiency. Fig. 1 to fig. 3 are schematic flow charts of an embodiment of a molding process of a signal wheel of an automobile transmission according to the present invention.

Referring to fig. 1, the forming process of the signal wheel of the automobile transmission comprises the following steps:

s10, providing raw material powder.

The requirements of the signal wheel of the automobile transmission are as follows: the size tolerance of the die parting surface of the part pressed compact is 0.15; the surface roughness of the part is Ra3.2; the dimensional tolerance of the non-molding surface is 0.1 min; the part hardness is 300HV5 min; the density of the part is not less than 6.9g/cm². In order to make the density, size and the like of the molded automobile transmission signal wheel meet the requirements, proper raw material powder is used.

Specifically, the raw material powder comprises the following components in percentage by weight: 0.5-0.8% of C, 1.6-2.4% of Cu, 3.6-4.4% of Ni, 1.3-1.7% of Mo, less than 2% of impurities and the balance of Fe. Signals acquired by the automobile transmission signal wheel are subjected to electromagnetic induction, C is an essential component in the automobile transmission signal wheel, but the magnetic performance is reduced to a certain extent due to excessive C content, so that C is preferably 0.5-0.8% in the forming process; the Cu is relatively soft, so that the pressing performance in subsequent pressing can be improved; by adding Cu, Ni and Mo and scientifically proportioning the Cu, the Ni and the Mo, the density and the hardness of the signal wheel of the automobile transmission are improved, and the signal wheel meets the requirements.

And S20, compacting the raw material powder to obtain a blank.

Pressing into compact, and pressing the powder into required shape under certain pressure. The invention is not limited to the specific equipment used for compaction, and in the examples of the invention, a 160Ton mechanical press is used for compaction.

Further, step S20 specifically includes: weighing 42-44 g of the raw material powder in proportion, and carrying out blank pressing on the raw material powder to obtain a blank. Wherein the proportion refers to 0.5-0.8% of C, 1.6-2.4% of Cu, 3.6-4.4% of Ni, 1.3-1.7% of Mo, less than 2% of impurities and the balance of Fe. 42-44 g of the raw material powder is weighed, so that a blank obtained by using the raw material powder pressed compact in the mass range is most consistent with the requirements of the embodiment of the invention on the size and the density of the signal wheel of the automobile transmission, and the material utilization rate is further improved.

Further, in step S20, the blank pressing speed is 8-12S/piece, such as 8S/piece, 9S/piece, 10S/piece, 11S/piece, 12S/piece, and the like, which is beneficial to improving the forming efficiency and facilitating mass continuous production.

Furthermore, step S20 may be performed as follows: and carrying out green pressing on the raw material powder to obtain a blank, carrying out pressure monitoring during green pressing, and removing the blank of which the monitoring value is inconsistent with a preset pressure value. The pressure monitoring is carried out during the blank pressing, the pressure during the blank pressing is a key factor for determining the blank quality, specifically, in the embodiment of the invention, the preset pressure value is in the range of 10-15 Ton, and the parts with abnormal pressure monitoring are automatically removed or the parts are early-warned, so that the production yield is facilitated.

Referring to fig. 2, after step 20 and before step 30, the method further includes:

and 21, carrying out weight detection on the blank, and rejecting the blank with a detection value not in accordance with a preset weight value.

And detecting the blank obtained by the pressed blank by 100% weight, wherein the preset weight value is in the range of 42-44 g, and the blank with the weight not meeting the requirement is rejected, so that the unqualified blank is prevented from flowing into the next procedure, and the production yield is further improved.

And S30, sintering and hardening the blank to obtain the automobile transmission signal wheel.

The sinter hardening is to combine the ordinary sintering and the quenching heat treatment for improving the material performance, and transform the raw material powder into a part or all of martensite structure to obtain a high-performance metallurgical product. The embodiment of the invention adopts the German Muller sintering hardening furnace, the propelling speed is 5.5m/h, and the blank enters the German Muller sintering hardening furnace in a single-layer flat laying manner, so that the sintering effect is better.

Step 30 specifically comprises: the blank is sequentially preheated, sintered and rapidly cooled to obtain the automobile transmission signal wheel, the preheating before sintering is favorable for sintering, the rapid cooling can accelerate the cooling speed of the blank, and the production efficiency is improved.

It should be noted that, step 30 is performed in a mixed gas of nitrogen and ammonia, so as to ensure an oxygen-free environment and prevent oxidation.

Further, the preheating temperature is 535-565 ℃, such as 535 ℃, 545 ℃, 550 ℃, 555 ℃, 565 ℃ and the like, and the preheating is more sufficient in the temperature range.

The rapid cooling speed is not limited, and preferably, in the embodiment of the invention, the rapid cooling speed is 2-3 ℃/s, such as 2 ℃/s, 2.3 ℃/s, 2.5 ℃/s, 2.8 ℃/s, 3 ℃/s and the like, so that the blank is rapidly cooled.

The sintering temperature is 1110-1130 ℃, such as 1110 ℃, 1115 ℃, 1120 ℃, 1125 ℃ and 1130 ℃, the sintering temperature is high, the performance of the subsequent automobile transmission signal wheel can meet the requirement by one-time sintering in the sintering temperature range, multiple times of sintering are not needed, the time consumption in the step 30 is reduced, and the production efficiency is improved.

The sintering time is 25-35 min, such as 25min, 28min, 30min, 32min, 35min and the like, so that the blank can be fully sintered.

Referring to fig. 3, after step 30, the method further includes:

and step 40, deburring the signal wheel of the automobile transmission.

The automobile transmission signal wheel generates burrs in the forming process, so that the deburring treatment is needed. The invention is not limited to the specific equipment used for deburring, and in the embodiment of the invention, a deburring machine is used for deburring. The existence of burr can influence the use of automotive transmission signal wheel, handles through getting rid of the burr, gets rid of the burr on the automotive transmission signal wheel, does benefit to the performance of automotive transmission signal wheel.

Further, after step 40, the method further includes:

and 50, cleaning the automobile transmission signal wheel subjected to deburring treatment.

The sintered signal wheel of the automobile transmission has the defects of surface oxidation and the like, and the requirement on the cleanliness and the surface quality of the signal wheel of the automobile transmission is higher, so that the step of cleaning the signal wheel of the automobile transmission after deburring is particularly critical, and the surface quality and the cleanliness of the signal wheel of the automobile transmission can be improved. Specifically, the automobile transmission signal wheel after deburring is cleaned through the ultrasonic cleaning machine, and the cleaning effect is good.

The technical solutions of the present invention are further described in detail below with reference to specific examples and test data, it should be understood that the following examples are merely illustrative of the present invention and are not intended to limit the present invention. Table 1 shows the amounts of the examples and the comparative examples, Table 2 shows the test results corresponding to Table 1, Table 3 shows the processing requirements for the signal wheel of the automobile transmission manufactured by the conventional molding process, and Table 4 shows the processing requirements for the signal wheel of the automobile transmission manufactured by the amount of example 1.

TABLE 1 amounts of examples 1 to 5, comparative examples 1 to 4

C(％)

Cu

Ni

Mo

Impurities

Fe

Example 1

0.6％

1.6％

3.8％

1.3％

1％

91.7％

Example 2

0.6％

1.8％

3.8％

1.5％

1.2％

89.8％

Example 3

0.8％

1.8％

4％

1.7％

0.8％

90.9％

Practice ofExample 4

0.5％

1.8％

4％

1.5％

90.7％

Example 5

0.5％

2％

4％

1.5％

0.8％

91.2％

Comparative example 1

0.3％

1.6％

3.2％

1.2％

1.5％

92.2％

Comparative example 2

0.4％

1.8％

3.5％

1.1％

0.8％

92.4％

Comparative example 3

0.5％

2.2％

3.3％

1.1％

1.5％

91.4％

Comparative example 4

0.5％

1.8％

3％

1.3％

3％

90.4％

Table 2 shows the test results obtained for examples 1 to 5 and comparative examples 1 to 4

Wherein the material cost refers to the raw material powder cost required for a single piece automotive transmission signal wheel. As can be seen from Table 2, the hardness values of the parts of the signal wheels of the transmission of the automobile obtained in examples 1 to 5 were larger than those of comparative examples 1 to 4, and were more than 300 HV.

TABLE 3 time required for conventional processing

Procedure (ii)	Production cost (Yuan)	Time of use(s)
			Material	0.36
Discharging	0.2	10
			Rough turning	0.50	30
Tempering	0.30	30
			Finish turning	0.50	30
Hole milling	0.40	24
			Milling tooth	1.50	72
Deburring	0.15
			Cleaning of	0.12
Total cost of	4.03
			When it is used in general		196

Wherein, traditional process flow does in proper order: blanking, rough turning, tempering, finish turning, hole milling, tooth milling, deburring and cleaning, wherein the production cost refers to the cost required for producing a single automobile transmission signal wheel. And the material utilization rate is 50% by dividing the mass of the signal wheel obtained after cleaning by the mass of the following material.

TABLE 4 processing requirements for processing as in example 1

Wherein, pressing means: pressing the raw material powder to obtain a blank, wherein the sintering and hardening refer to: and pressing the raw material powder to obtain a blank, wherein the production cost refers to the cost required for producing a single automobile transmission signal wheel. And the material utilization rate is 99% by dividing the mass of the signal wheel obtained after cleaning by the mass of the mixed material.

As can be seen from tables 3 and 4, compared with the conventional molding process, the material of example 1 of the present invention has high utilization rate, lower required production cost, lower required processing time, and higher production efficiency.

The above is only a preferred embodiment of the present invention, and it is not intended to limit the scope of the invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall be included in the scope of the present invention.

Claims

1. A molding process of a signal wheel of an automobile transmission is characterized by comprising the following steps:

providing a raw material powder;

pressing the raw material powder to obtain a blank;

2. The process for forming a signal wheel of an automobile transmission according to claim 1, wherein the raw material powder comprises the following components in percentage by weight:

3. The process for forming a signal wheel of an automobile transmission according to claim 1, wherein the step of compacting the raw material powder to obtain a blank comprises:

4. The forming process of the automobile transmission signal wheel as claimed in claim 1, wherein in the step of compacting the raw material powder to obtain the blank, the compacting speed is 8-12 s/piece.

5. The process for forming a signal wheel of an automobile transmission according to claim 1, wherein the step of compacting the raw material powder into a blank comprises the steps of:

6. The process for forming a signal wheel of an automobile transmission according to claim 1, wherein after the step of compacting the raw material powder to obtain a blank and before the step of sintering and hardening the blank to obtain the signal wheel of the automobile transmission, the process further comprises:

7. The process for forming a signal wheel of an automobile transmission according to claim 1, wherein the step of sinter hardening the blank to obtain the signal wheel of the automobile transmission comprises the steps of:

8. The process for forming a signal wheel of an automobile transmission according to claim 7, wherein the steps of preheating, sintering and rapidly cooling the blank in sequence to obtain the signal wheel of the automobile transmission are carried out in a mixed gas of nitrogen and ammonia.

9. The forming process of the automobile transmission signal wheel as claimed in claim 7, wherein the preheating temperature is 535-565 ℃; and/or the presence of a gas in the gas,

the rapid cooling speed is 2-3 ℃/s; and/or the presence of a gas in the gas,

the sintering time is 25-35 min.

10. The process for forming a signal wheel of an automotive transmission according to claim 1, wherein said step of sinter hardening said blank to obtain a signal wheel of an automotive transmission further comprises:

removing burrs of the automobile transmission signal wheel;

and cleaning the automobile transmission signal wheel after deburring.