A fixture structure for drilling a step surface of an end cover

Abstract

The utility model provides a kind of fixture structure for connecting end cover step face drilling processing, including inverted L shape clamping body, mandrel, positioning pin, detachable drill jig plate and drill bushing;Mandrel is arranged in the clamping body mounting hole, for inserting the coaxial positioning of connecting end cover center hole;Positioning pin is inserted into the clamping body positioning hole and is inserted into the connecting end cover mating hole, restricts its rotational freedom;Drill jig plate is vertically installed in the outside of clamping body, is equipped with guide hole and is embedded drill bushing, guiding drill bit along axial drilling end cover step face forms through-hole.The utility model solves the technical problem that existing fixture positioning is not accurate, guiding precision is poor, it is difficult to meet the technical problem of end cover step face drilling processing precision and consistency requirement.

Description

Technical Field

[0001] This utility model relates to the field of machining technology, and in particular to a fixture structure for drilling holes in the stepped surface of a connecting end cap. Background Technology

[0002] Connecting end caps, as a typical disc-type part, are widely used in equipment such as electric motors and machine tools, often for axial positioning, dustproof sealing, or connection and fixing. Their structure typically features internal holes, stepped surfaces, and evenly distributed holes; the machining accuracy directly affects the assembly quality and operational stability of the entire machine.

[0003] In existing technologies, the machining of connecting end cap parts often employs general-purpose fixtures or simple positioning structures for clamping. These fixture structures typically cannot effectively constrain the workpiece's six degrees of freedom, making them prone to slight displacements during machining, leading to hole position deviations or insufficient perpendicularity, especially noticeable when machining single holes on stepped surfaces. Furthermore, conventional drilling fixtures have limitations in positioning accuracy and guiding rigidity, and the drill bit may wobble during feed, affecting the positional accuracy and geometry of the machined hole.

[0004] Furthermore, while some fixture structures possess guiding functions, they generally suffer from problems such as complex structures, cumbersome assembly, or difficulty in replacing suitable parts, making it difficult to meet the comprehensive requirements of efficiency, precision, and versatility in batch processing. Therefore, there is an urgent need for a fixture structure that is simple in structure, reliable in positioning, and has high guiding accuracy, suitable for drilling holes in the stepped surfaces of connecting end caps, in order to improve processing efficiency and product consistency. Utility Model Content

[0005] In order to overcome the shortcomings of the existing technology, the purpose of this utility model is to provide a fixture structure with simple structure, reliable positioning and high guiding accuracy for drilling the stepped surface of the connecting end cap.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A fixture structure for drilling a stepped surface of a connecting end cap includes a fixture body, a mandrel, a locating pin, a removable drill template, and a drill sleeve. The fixture body is an inverted L-shaped integral structure, including a vertical support surface and a horizontal base fixedly connected thereto. A through mounting hole is provided on the support surface along the horizontal direction. The mandrel is horizontally inserted into the mounting hole and extends out of the fixture body for insertion into the center hole of the connecting end cap to achieve coaxial positioning. A locating hole is provided at the top of the horizontal base. The locating pin is inserted into the locating hole and into a mating hole on the side wall of the connecting end cap to restrict the rotational freedom of the connecting end cap. The drill template is a plate-like structure, vertically fitted and installed on the outside of the support surface and fixedly connected by fasteners. A through guide hole is provided on the drill template. The guide hole penetrates the drill template vertically and is located directly above the hole to be machined on the stepped surface of the connecting end cap. A drill sleeve is embedded in the guide hole. The drill sleeve is used to guide the drill bit into the stepped surface of the end cap along the axial direction to form a directional drilling through hole.

[0007] Furthermore, one end of the mandrel is provided with a limiting shoulder to limit its insertion depth and abut against the inner end face of the connecting end cap to prevent the mandrel from moving axially.

[0008] Furthermore, the positioning pin is a cylindrical pin structure, and its insertion direction is perpendicular to the axis of the mandrel, which is used to accurately limit the rotational freedom of the connecting end cap.

[0009] Furthermore, the guide hole of the drill template and the drill bushing are interference fit, and the drill bushing is made of high-hardness steel to enhance guiding accuracy and wear resistance.

[0010] Furthermore, the support surface of the clamping body is a planar machined structure and is set perpendicular to the axis of the mandrel to ensure the stable positioning and axial perpendicularity of the connecting end cap during clamping.

[0011] Furthermore, the horizontal base of the clamping body is provided with a positioning stop to assist in the initial positioning of the drill template during installation, ensuring that the guide hole is aligned with the machining position.

[0012] Furthermore, the drill template can be detachably installed on the fixture with screws, making it easy to replace different drill templates when processing connection end caps of different specifications to meet different hole position requirements.

[0013] Furthermore, a clearance is provided between the inner hole of the drill bushing and the diameter of the drill bit, with the clearance ranging from 0.02mm to 0.05mm, to ensure a balance between the drill bit guiding accuracy and the smooth discharge of chips during the drilling process.

[0014] The aforementioned fixture structure for drilling the stepped surface of the connecting end cap utilizes an inverted L-shaped integrated fixture body and a mandrel to achieve coaxial positioning of the end cap's inner hole. Positioning pins effectively restrict its rotational degrees of freedom, and combined with a high-precision drill template and drill bushing, rigid guidance in the drilling direction is achieved. This solves the problems of insufficient six-degree-of-freedom constraint, large positioning errors, severe drilling runout, and cumbersome replacement associated with existing fixtures. This fixture structure is compact, easy to operate, and provides high guiding accuracy, significantly improving the consistency and efficiency of drilling the stepped surface of the connecting end cap. It is suitable for rapid switching and stable processing of end caps of different specifications, meeting the precision and versatility requirements of mass production. Attached Figure Description

[0015] Figure 1 This is a cross-sectional view of the fixture structure provided by this utility model. Detailed Implementation

[0016] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0017] like Figure 1 As shown, this application provides a fixture structure for drilling the stepped surface of a connecting end cap, including a fixture body 1, a mandrel 2, a locating pin 3, a removable drill template 4, and a drill sleeve 5.

[0018] Specifically, the clamping body 1 is an inverted L-shaped integral structure, including a vertical support surface 11 and a horizontal base 12 fixedly connected thereto. A through mounting hole 13 is provided on the support surface 11 along the horizontal direction. The mandrel 2 is horizontally inserted into the mounting hole 13 and extends out of the clamping body 1 for insertion into the center hole of the connecting end cover to achieve coaxial positioning. A positioning hole is provided at the top of the horizontal base 12. A positioning pin 3 is inserted into the positioning hole and into the mating hole on the side wall of the connecting end cover to restrict the rotational freedom of the connecting end cover. The drill template 4 is a plate-shaped structure, vertically fitted and installed on the outside of the support surface 11 and fixedly connected by fasteners 6. A through guide hole 41 is provided on the drill template 4. The guide hole 41 penetrates the drill template 4 in the vertical direction and is located directly above the hole to be machined on the stepped surface of the connecting end cover. A drill sleeve 5 is embedded in the guide hole 41. The drill sleeve 5 is used to guide the drill bit into the stepped surface of the end cover in the axial direction to form a directional drilling through hole.

[0019] This fixture structure achieves high-precision positioning and guiding control for drilling the end cap. The coaxial fit between the mandrel 2 and the center hole of the end cap ensures radial consistency of the hole position; the locating pin 3 restricts the rotational freedom of the end cap, preventing angular deviations during machining; the detachable connection between the drill template 4 and the fixture body 1 enhances flexibility to adapt to different machining needs; and the drill bushing 5 provides high-precision drill bit guidance, ensuring hole machining quality. Furthermore, the overall structure facilitates clamping and disassembly, improving process efficiency and demonstrating good versatility and practicality.

[0020] One end of the mandrel 2 is provided with a limiting shoulder to limit its insertion depth and abut against the inner end face of the connecting end cap, preventing axial movement of the mandrel 2. The limiting shoulder enables the mandrel 2 to have a self-limiting function during use, effectively avoiding positioning deviations caused by excessive or insufficient insertion, improving the consistency of end cap positioning and the efficiency of repeated clamping. At the same time, this structure eliminates the need for an additional limiting mechanism, simplifying fixture design and reducing manufacturing and maintenance costs.

[0021] The locating pin 3 is a cylindrical pin structure, and its insertion direction is perpendicular to the axis of the mandrel 2. It is used to precisely limit the rotational freedom of the connecting end cap. Using the cylindrical pin 3 as the limiting element results in a simple structure, high machining accuracy, and facilitates high-precision angular positioning. The insertion direction being perpendicular to the mandrel 2 promotes independent and non-interfering clamping operations, thereby improving clamping efficiency. Furthermore, this structure facilitates maintenance and replacement, reducing the overall cost of using and maintaining the fixture system, while ensuring the stability of the end cap's posture during machining.

[0022] The guide hole 41 of the drill template 4 and the drill bushing 5 are interference-fitted. The drill bushing 5 is made of high-hardness steel to enhance guiding accuracy and wear resistance. The interference fit improves the connection strength between the drill bushing 5 and the drill template 4, enhancing the rigidity and stability of the overall structure. The high-hardness material of the drill bushing 5 significantly improves wear resistance and service life, reducing the decrease in guiding accuracy caused by wear. Furthermore, this structure reduces maintenance frequency, making it suitable for batch, high-precision drilling operations, improving processing consistency and efficiency.

[0023] The support surface 11 of the fixture body 1 is a machined plane structure and is perpendicular to the axis of the mandrel 2. This ensures the stable positioning and axial perpendicularity of the connecting end cap during clamping. By setting a plane support surface 11 perpendicular to the mandrel 2, the posture stability and positioning consistency of the connecting end cap during clamping are improved. This structure helps to improve the axial perpendicularity of the hole position during drilling, avoiding hole tilting or hole deformation due to clamping deviations, thereby enhancing product processing quality and consistency.

[0024] A positioning stop is provided on the horizontal base 12 of the fixture body 1 to assist in the initial positioning of the drill template 4 during installation, ensuring that the guide hole 41 is aligned with the machining position. This stop is located along the edge of the installation area of ​​the drill template 4, forming a stepped surface or groove structure. When the drill template 4 is installed on the fixture body 1, its lower edge naturally conforms to the stop surface, thus achieving initial positional limitation and effectively avoiding installation errors caused by inaccurate manual positioning. This structure ensures that the guide hole 41 on the drill template 4 can be accurately aligned with the position of the hole to be machined on the stepped surface of the connecting end cap, improving the overall accuracy of the drilling process.

[0025] The drill template 4 is detachably mounted to the fixture 1 via screws, facilitating the replacement of different drill templates 4 to accommodate varying hole positions when machining different specifications of connecting end caps. During drilling of the connecting end caps, the machining positioning position can be quickly adjusted simply by replacing the corresponding drill template 4 according to the structural dimensions and hole distribution of different end caps. The screw connection method is simple and reliable, providing sufficient clamping force to ensure the drill template remains stable during machining, while also offering high repeatability.

[0026] A clearance of 0.02mm to 0.05mm is provided between the inner hole of the drill bushing 5 and the diameter of the drill bit to ensure a balance between drill bit guiding accuracy and smooth chip removal during drilling. Specifically, the clearance is controlled within the range of 0.02mm to 0.05mm to accommodate the dynamic displacement of the drill bit caused by thermal expansion or slight wobble during machining, while allowing sufficient space for chip removal to prevent clogging, wear, or drill bit misalignment caused by poor chip removal, thereby ensuring hole quality and machining stability.

[0027] The above description of embodiments of the present invention, through which those skilled in the art are able to implement or use the present invention, will be readily apparent to those skilled in the art. Various modifications to these embodiments will be readily apparent to those skilled in the art. The general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novelty disclosed herein.

Claims

1. A fixture structure for drilling holes in the stepped surface of a connecting end cap, characterized in that, It includes a clamping body (1), a mandrel (2), a positioning pin (3), a removable drill template (4), and a drill bushing (5); The clamp body (1) is an inverted L-shaped integral structure, including a vertical support surface (11) and a horizontal base (12) fixedly connected thereto. A through mounting hole (13) is provided on the support surface (11) along the horizontal direction. The spindle (2) is horizontally inserted into the mounting hole (13) and extends out of the clamp body (1) for insertion into the center hole of the connecting end cap to achieve coaxial positioning. The top of the horizontal base (12) is provided with a positioning hole, and the positioning pin (3) is inserted into the positioning hole and inserted into the mating hole on the side wall of the connecting end cover to restrict the rotational freedom of the connecting end cover. The drilling template (4) is a plate-shaped structure, which is vertically fitted to the outside of the support surface (11) and fixedly connected by fasteners (6). The drilling template (4) is provided with a through guide hole (41). The guide hole (41) penetrates the drill template (4) in the vertical direction and is located directly above the hole to be machined on the step surface of the connecting end cap. A drill sleeve (5) is embedded in the guide hole (41). The drill sleeve (5) is used to guide the drill bit to enter the step surface of the end cap in the axial direction to form a directional drilling through hole.

2. The clamp structure according to claim 1, characterized in that, The mandrel (2) has a limiting shoulder at one end, which is used to limit its insertion depth and abut against the inner end face of the connecting end cap to prevent the mandrel (2) from moving axially.

3. The clamp structure according to claim 1, characterized in that, The positioning pin (3) is a cylindrical pin structure, and its insertion direction is perpendicular to the axis of the spindle (2), which is used to achieve precise limiting of the rotational freedom of the connecting end cap.

4. The clamp structure according to claim 1, characterized in that, The guide hole (41) of the drill template (4) and the drill sleeve (5) are interference fit. The drill sleeve (5) is made of high hardness steel to enhance the guiding accuracy and wear resistance.

5. The clamp structure according to claim 1, characterized in that, The support surface (11) of the clamping body (1) is a planar machined structure and is set perpendicular to the axis of the spindle (2) to ensure the stable positioning and axial perpendicularity of the connecting end cover during clamping.

6. The clamp structure according to claim 1, characterized in that, The clamping body (1) has a positioning stop on its horizontal base (12) to assist in the initial positioning of the drilling template (4) during installation, ensuring that the guide hole (41) is aligned with the processing position.

7. The clamp structure according to claim 1, characterized in that, The drill template (4) is detachably installed on the fixture (1) by screws, which makes it easy to replace different drill templates (4) when processing connection end caps of different specifications to meet different hole requirements.

8. The clamp structure according to claim 1, characterized in that, The inner hole of the drill bushing (5) is provided with a fitting clearance between the drill bit diameter and the drill bit diameter. The fitting clearance ranges from 0.02mm to 0.05mm to ensure a balance between the drill bit guiding accuracy and the smooth discharge of chips during the drilling process.

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