Processing technology of elastic interlocking block

Abstract

The invention discloses a processing technology of an elastic interlocking block, which comprises the following steps: S1, pressing and forming: after proportioning powder metallurgy components required by the interlocking block, pressing to form an interlocking block green body; an axially-penetrating concave groove is formed in the position, corresponding to the open groove, of the interlocking block green body and used for reducing the wall thickness of the interlocking block body at the position, a chamfer is formed at the end of the concave groove, a technological protruding block is further formed on the interlocking block green body, one side of the technological protruding block extends to be flush with the end of the interlocking block body, and the other side of the technological protruding block is connected with the lug-shaped protrusion; s2, sintering: performing high-temperature sintering on the interlocking block green body to form an interlocking block preformed part; s3, machining is conducted for the first time, specifically, the interlocking block preformed piece is machined, the technological protruding block is removed, and a U-shaped positioning transverse groove is machined in the transverse groove protruding block; s4, finishing: finishing the interlocking block preformed part; and S5, secondary machining is conducted, specifically, the preformed part is machined from the position of the concave groove, an open groove is formed, then cleaning and full inspection are conducted, machining is completed, and the elastic interlocking block is obtained.

Description

Technical Field

[0001] The invention relates to the technical field of powder metallurgy, and in particular to a processing technology for elastic interlocking blocks. Background Art

[0002] The interlocking block is an important part in the gearbox. The interlocking block includes an interlocking block body, which is a thin-walled cylindrical structure with a through hole (i.e., a hollow structure). An open groove is opened on the outer circular wall of the interlocking block body along its axial direction. Symmetrical ear-shaped protrusions are also provided on the outer circular wall of the interlocking block body. The ear-shaped protrusions are symmetrically arranged on both sides of the open groove. The ear-shaped protrusion on one side is connected to a transverse groove protrusion arranged on the outer circular wall of the interlocking block body. A U-shaped positioning transverse groove is provided on the transverse groove protrusion. The structure of the interlocking block is as follows Figure 1 As shown in the figure. Due to the presence of the transverse groove protrusion on the outer circumferential wall of the interlocking block body and the forming characteristics of powder metallurgy, it is necessary to set a process protrusion on the outer circumferential wall of the interlocking block body green body at a position opposite to the transverse groove protrusion during the green body pressing process. In addition, the transverse groove and ear-shaped protrusion end faces cannot be directly pressed and need to be "added" during the forming process and then removed by machining.

[0003] At present, the existing processing technology of interlocking blocks is generally divided into two processing methods: (1) Method 1 includes: green body pressing and forming (open grooves are formed in the green body) → sintering → machining (removing process bumps and machining U-shaped positioning transverse grooves) → deburring → cleaning → full appearance inspection; (2) Method 2 includes: green body pressing and forming → sintering → machining (open grooves are formed, process bumps are removed, and U-shaped positioning transverse grooves are machined) → deburring → cleaning → full appearance inspection.

[0004] However, the two commonly used interlocking block processing methods mentioned above both have different process defects: for example, in the green body pressing process, the first option is to first form an open groove in the green body. However, after the green body is sintered, due to the irregularity of the part, the roundness of the inner hole and the size of the open groove will fluctuate greatly, which will seriously affect the subsequent part size changes. At the same time, in the subsequent machining process, since the part has already been opened with an open groove, the part will undergo elastic deformation during the machining process, resulting in part size deviations. In the second option, the open groove is not formed first during the green body pressing process, and the part is subsequently clamped once through the machining process. The last process is to mill out the open groove. Although this processing method of the second option will not cause problems with the part size in the early stage, in the subsequent deburring process, whether it is polishing or sandblasting, it will cause elastic deformation of the part and affect the part size. It is difficult to meet the actual part size requirements and has low precision. Summary of the Invention

[0005] The purpose of the present invention is to propose a new elastic interlocking block processing technology to solve the problem of low processing accuracy in the existing interlocking block processing technology, which affects the part size after processing, resulting in low part size accuracy and not meeting customer requirements.

[0006] To achieve the above object, the present invention is achieved through the following technical solutions:

[0007] The present invention provides a processing technology for an elastic interlocking block, wherein the elastic interlocking block includes the following structural arrangement:

[0008] The interlocking block body is configured as a hollow thin-walled cylindrical structure, and an open groove is axially opened on the outer circular wall of the interlocking block body and runs through both ends;

[0009] Two ear-shaped protrusions are symmetrically arranged on the outer circular wall of the interlocking block body, and the two ear-shaped protrusions are respectively arranged on both sides of the opening groove;

[0010] and a transverse groove protrusion, which is provided on the outer circular wall of the interlocking block body, one side of the transverse groove protrusion extends to be flush with the end of the interlocking block body, and the other side is connected to one of the ear-shaped protrusions, and the transverse groove protrusion is also provided with a U-shaped positioning transverse groove extending along the circumference of the interlocking block body;

[0011] The processing technology of the elastic interlocking block comprises the following steps:

[0012] S1. Pressing and forming: mixing the powder metallurgy components required for the interlocking block and pressing to form an interlocking block green body;

[0013] wherein, an axially penetrating concave groove is pressed and formed on the interlocking block green body at a position corresponding to the open groove, the concave groove is used to reduce the wall thickness of the interlocking block body at that location, and a chamfer is also pressed and formed at the end of the concave groove; a process protrusion is also pressed and formed on the interlocking block green body, one side of the process protrusion extends to be flush with the other end of the interlocking block body, and the other side of the process protrusion is connected to the ear-shaped protrusion (specifically, the transverse groove protrusion and the process protrusion are connected to the same ear-shaped protrusion, and the transverse groove protrusion and the process protrusion are respectively arranged on both sides of the ear-shaped protrusion, and one side of the transverse groove protrusion and the process protrusion respectively extend to be flush with the two ends of the hollow thin-walled cylindrical interlocking block body);

[0014] S2. Sintering: sintering the interlocking block green body at a high temperature to form an interlocking block preform. After sintering, the structure does not change, but the strength changes.

[0015] S3, machining step 1: machining the interlocking block preform to remove the process protrusion and machine a U-shaped positioning transverse groove on the transverse groove protrusion;

[0016] S4, finishing: performing surface finishing on the interlocking block preform;

[0017] S5, machining step 2: machining the interlocking block preform from the concave groove to open the groove, then cleaning and inspecting the appearance to complete the machining and obtain the elastic interlocking block.

[0018] Furthermore, a processing technology for an elastic interlocking block: in step S1, the wall thickness of the interlocking block body at the thinned portion of the concave groove is recorded as H1, and the wall thickness of the interlocking block body at the unthinned portion is recorded as H, then: H / 5

[0019] Furthermore, a processing technology for an elastic interlocking block: the width of the concave groove (groove width) in step S1 and the wall thickness H1 of the interlocking block body at the thinned portion satisfy: 1 / 5 groove width < H1 < 4 / 5 groove width.

[0020] Furthermore, a processing technology for an elastic interlocking block: in step S1, a chamfer of C0.5 to C1.0 is reserved at the end of the concave groove.

[0021] Furthermore, a processing technology for a resilient interlocking block: the sintering temperature in step S2 is 1100-1150°C.

[0022] Furthermore, a processing technology for a flexible interlocking block: the finishing time in step S4 is 5.0 to 10.0 minutes.

[0023] Furthermore, a processing technology for an elastic interlocking block is provided: when opening an open groove in step S5, rough milling is first performed and then fine milling is performed to obtain the open groove; wherein, the tool diameter used in rough milling and fine milling is set to the width of the open groove minus 0.01 to 0.03 mm, and the tool diameter for fine milling is larger than the rough milling tool.

[0024] Specifically, the axial direction of the interlocking block body is the length direction of the opening groove, and the radial direction is the width direction thereof.

[0025] Beneficial effects of the present invention:

[0026] ​(1) The present invention proposes a new processing technology for elastic interlocking blocks, which has the following improvements compared with the existing processing technology for interlocking blocks: ① In the processing technology of the present invention, a concave groove structure is first pressed to form at the position corresponding to the opening groove on the green body during the green body pressing process, which can reduce the machining allowance of the second machining sequence as much as possible, thereby improving the tool life of the second machining sequence, and the opening groove is processed separately in the second machining sequence, avoiding the problem that the part is deformed again after the groove is opened and affecting the product size; ② In the processing technology of the present invention, a chamfer is reserved at the position of the opening groove during the green body pressing process, which can prevent burrs, and can effectively avoid the burr problem when the opening groove is milled later, thereby avoiding affecting the dimensional accuracy of the part.

[0027] (2) The processing technology of the present invention removes the protrusions of the forming process and forms the U-shaped positioning transverse groove in the first machining process, which can avoid the influence of subsequent processing on the size of the opening groove; the process of the present invention adopts the method of polishing and deburring after machining, which can effectively remove the burrs caused by the first machining process on the one hand, and can also effectively eliminate the stress of the part itself, and avoid the stress release in the subsequent opening groove processing process causing the deformation of the part opening groove size. In addition, the second machining process of the present invention adopts the machining process of rough milling first and then fine milling. Since the part is first rough milled before fine milling, the deformation of the part can be further reduced.

[0028] (3) The processing technology of the elastic interlocking block provided by the present invention adopts the steps of pressing, sintering, first-order machining, polishing, second-order machining, and cleaning, and places the processing of the open groove in the last step. At the same time, during the green forming process, a processing chamfer is reserved at the position of the open groove to avoid burrs during the milling process of the open groove, thereby making the size of the open groove stable during the processing process, and the product precision high, meeting customer requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 It is a structural diagram of the interlocking block;

[0031] Figures 2-3 Schematic diagram of the structure of the interlocking block green body pressed and formed in step S1 of Example 1 of the present invention;

[0032] Figure 4 for Figure 2 The partial enlarged view of the middle A area is a schematic diagram of the concave groove thinning interlocking block body;

[0033] Figure 5 This is a schematic structural diagram of the interlocking block preform formed after machining in step S3 according to Example 1 of the present invention;

[0034] Figure 6 This is a schematic diagram of the structure of the elastic interlocking block formed after the second machining process in step S5 of Example 1 of the present invention, and Figure 1 The interlocking blocks shown have the same structure.

[0035] The following are marked in the figure:

[0036] 1-interlocking block body, 2-ear-shaped protrusion, 3-transverse groove protrusion, 4-interlocking block green body, 11-opening groove, 31-U-shaped positioning transverse groove, 41-concave groove, 42-chamfer, 43-process protrusion. DETAILED DESCRIPTION

[0037] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0038] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", "top", "bottom", etc., indicating directions or positional relationships, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood 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 one or more of the features. Moreover, the terms "first", "second", etc. are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein.

[0039] Example 1

[0040] like Figures 1 to 6 As shown, this embodiment 1 provides a processing technology for an elastic interlocking block, and the interlocking block includes the following structural settings:

[0041] The interlocking block body 1 is configured as a hollow thin-walled cylindrical structure, and an open groove 11 is axially opened on the outer circular wall of the interlocking block body 1 and passes through both ends;

[0042] Two ear-shaped protrusions 2 are symmetrically arranged on the outer circular wall of the interlocking block body 1, and the two ear-shaped protrusions are respectively arranged on both sides of the opening groove 11;

[0043] and a transverse groove protrusion 3, which is provided on the outer circular wall of the interlocking block body 1, one side of the transverse groove protrusion 3 extends to be flush with the end of the interlocking block body 1, and the other side is connected to one of the ear-shaped protrusions 2, and the transverse groove protrusion 3 is provided with a U-shaped positioning transverse groove 31 extending along the circumference of the interlocking block body 1;

[0044] The processing technology of the elastic interlocking block includes the following specific steps:

[0045] S1. Pressing and forming: After the powder metallurgy components required for the interlocking block are mixed, the interlocking block green body 4 is formed by pressing using a CNC forming press;

[0046] Among them, an axially penetrating concave groove 41 is pressed and formed on the interlocking block green body 4 at a position corresponding to the open groove 11, which is used to thin the wall thickness of the interlocking block main body 1 at the location of the concave groove 41, and chamfers 42 are also pressed and formed at both ends of the concave groove 41 (equivalent to the reserved chamfers 42 at the end corresponding to the position of the open groove 11 on the interlocking block green body 4), and a process protrusion 43 is also pressed and formed on the interlocking block green body 4 (due to the presence of the transverse groove protrusion 3 on the outer circular wall of the interlocking block main body 1, based on the forming characteristics of powder metallurgy, it is necessary to During the press-forming process of the blank 4, a process protrusion 43 is provided on the outer circular wall of the interlocking block main body green blank at a position opposite to the transverse groove protrusion 3. One side of the process protrusion 43 extends to be flush with the other end of the interlocking block main body 1, and the other side is connected to the ear-shaped protrusion 2. Specifically, the transverse groove protrusion 3 and the process protrusion 43 are connected to the same ear-shaped protrusion 2, and the transverse groove protrusion 3 and the process protrusion 43 are respectively provided on both sides of the ear-shaped protrusion 2. One side of the transverse groove protrusion 3 and the process protrusion 43 respectively extends to be flush with the two ends of the hollow thin-walled cylindrical interlocking block main body 1.

[0047] Specifically, in step S1, the wall thickness of the interlocking block body 1 at the thinned portion of the concave groove 41 is recorded as H1, and the wall thickness of the interlocking block body 1 not at the thinned portion is recorded as H, then H / 5

[0048] ​S2, sintering: sintering the interlocking block green body 4 at a high temperature of 1100-1150° C. to form an interlocking block preform;

[0049] S3, machining step 1: machining the interlocking block preform to remove the process protrusion 43 and simultaneously machining a U-shaped positioning transverse groove 31 on the transverse groove protrusion 3;

[0050] S4, polishing: performing surface polishing on the interlocking block preform for 5.0 to 10.0 minutes;

[0051] S5, machining step 2: rough milling is first performed on the interlocking block preform from the concave groove 41, and then fine milling is performed to mill out the opening groove 11 (when milling the opening groove 11, the diameter of the tool used for rough milling and fine milling is set to the width of the opening groove 11 minus 0.01 to 0.03 mm, and the diameter of the tool used for fine milling is larger than the rough milling tool), and then cleaning and full appearance inspection are completed to complete the processing to obtain the elastic interlocking block.

[0052] Specifically, the interlocking block blanks 4 in this embodiment are made from low-carbon steel, which has a ferrite and pearlite microstructure after sintering. The sintered blanks have low strength (surface hardness of approximately 80 HB), making them susceptible to deformation during subsequent machining and clamping, resulting in dimensional deviations. Therefore, this embodiment provides a processing technique that addresses the problem of interlocking blocks made of this material being susceptible to deformation and poor dimensional accuracy during subsequent machining. Furthermore, to minimize deformation during part milling, single-side down milling can be used to control cutting accuracy, reduce cutting thickness, ensure consistent cutting texture, and further minimize part deformation.

[0053] The processing technology of the elastic interlocking block provided by the present invention does not require the formation of an open groove in advance during the interlocking block green body pressing process. Instead, a concave groove structure that can reduce the wall thickness of the interlocking block body is pre-pressed at a position corresponding to the open groove on the green body during the green body pressing process. Since the open groove is not formed in advance on the green body, the problem of elastic deformation of the parts due to the previously opened open groove will not occur during the subsequent processing process, and the dimensional accuracy of the parts can be guaranteed. In addition, the structural setting of the concave groove can also reduce the machining allowance when the open groove is subsequently milled, thereby improving the service life of the machining tool. At the same time, the processing technology of the present invention also reserves an anti-burr chamfer at a position corresponding to the open groove on the green body during the green body pressing process, which can effectively avoid burrs when the open groove is subsequently machined, thereby solving the problem of elastic deformation of the parts during the deburring process in the existing interlocking block processing technology, which affects the dimensional accuracy of the product.

[0054] The above preferred embodiments of the present invention are only used to explain the present invention and are not used to limit the present invention. Any obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. A processing technology for elastic interlocking blocks, characterized in that: The interlocking block comprises: The interlocking block body (1) is configured as a hollow thin-walled cylindrical structure, and an open groove (11) is axially opened on the outer wall thereof and passes through both ends; Two ear-shaped protrusions (2) are symmetrically arranged on the outer circular wall of the interlocking block body (1) and are respectively arranged on both sides of the opening groove (11); and a transverse groove protrusion (3) provided on the outer circular wall of the interlocking block body (1), one side of which extends to be flush with the end of the interlocking block body (1), and the other side is connected to the ear-shaped protrusion (2), and the transverse groove protrusion (3) is provided with a U-shaped positioning transverse groove (31) extending along the circumference of the interlocking block body (1); The processing technology of the interlocking block includes: S1. Pressing and forming: mixing the powder metallurgy components required for the interlocking block and pressing to form an interlocking block green body (4); A concave groove (41) extending axially through the interlocking block blank (4) is formed at a position corresponding to the opening groove (11) for reducing the wall thickness of the interlocking block body (1) at that position, and a chamfer (42) is formed at the end of the concave groove (41). A process protrusion (43) is also formed on the interlocking block blank (4), and one side of the process protrusion (43) extends to be flush with the other end of the interlocking block body (1), and the other side is connected to the ear-shaped protrusion (2); S2, sintering: sintering the interlocking block green body (4) at a high temperature to form an interlocking block preform; S3, machining sequence 1: machining the interlocking block preform, removing the process protrusion (43) and machining a U-shaped positioning transverse groove (31) on the transverse groove protrusion (3); S4, finishing: performing surface finishing on the interlocking block preform; S5, machining step 2: machining the preformed part at the concave groove (41), opening the opening groove (11), and then cleaning and fully inspecting to complete the machining and obtain the elastic interlocking block.

2. The processing technology of the elastic interlocking block according to claim 1, characterized in that: In step S1, the wall thickness of the interlocking block body (1) at the thinned portion by the concave groove (41) is recorded as H1, and the wall thickness of the interlocking block body (1) at the unthinned portion is recorded as H, and the following is satisfied: H / 5<H1<H.

3. The processing technology of the elastic interlocking block according to claim 2, characterized in that: The width of the concave groove (41) in step S1 and the wall thickness H1 of the interlocking block body (1) at the thinned portion satisfy the following relationship: 1 / 5 groove width < H1 < 4 / 5 groove width.

4. The processing technology of the elastic interlocking block according to claim 1, characterized in that: In step S1, a chamfer (42) of C0.5 to C1.0 is reserved at the end of the concave groove (41).

5. The processing technology of the elastic interlocking block according to claim 1, characterized in that: The sintering temperature in step S2 is 1100-1150°C.

6. The processing technology of the elastic interlocking block according to claim 1, characterized in that: The polishing time in step S4 is 5.0 to 10.0 minutes.

7. The processing technology of the elastic interlocking block according to claim 1, characterized in that: When the opening slot (11) is formed in step S5, rough milling is first performed and then fine milling is performed to obtain the opening slot (11); The tool diameter used in rough milling and fine milling is set to the width of the opening slot minus 0.01 to 0.03 mm, and the tool diameter for fine milling is larger than that for rough milling.

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