A Z-shaped balance elbow turning fixture

Abstract

This invention proposes a Z-shaped balance elbow turning fixture, which includes a flange, base, support body, center, counterweight, and fastening bolts. The machining method includes rough boring of the end face, inner hole – rough turning of the large shaft – rough turning of the small shaft – finish boring of the end face, inner hole – finish turning of the large shaft – finish turning of the small shaft – milling of the outer shape and drilling – broaching (wire EDM splines), etc. This invention is applicable to the machining of multiple models and large batches of Z-shaped balance elbow products, ensuring stable and reliable product machining quality, and improving the overall product quality pass rate and machining efficiency.

Description

Technical Field

[0001] This utility model belongs to the field of mechanical manufacturing technology, specifically relating to a Z-shaped balanced elbow turning fixture. Background Technology

[0002] The balance elbow is a crucial component of the mobility system of tracked special vehicles, connecting the vehicle body to the road wheels. The balance elbow transfers the significant impact energy generated by the road wheel's movement to the torsion shaft, thus reducing the impact force on the vehicle body and converting rigid impacts into flexible ones. A typical balance elbow assembly includes a splined shaft, the balance elbow itself, and the road wheel axle. A Z-shaped balance elbow is an integrated unit that combines the splined shaft, the balance elbow, and the road wheel axle; its structure is as follows... Figure 1a and 1b As shown, it features high mobility, high reliability, and lightweight design, and has been widely used in modern special vehicle mobility systems.

[0003] Because Z-shaped balance elbows are irregularly shaped and generally large and heavy, requiring high material removal rates and high dimensional and positional accuracy, their machining cycle is lengthy and involves numerous processes, including horizontal boring machines, CNC lathes, machining centers, broaching machines, and wire EDM machines, as well as various trades. In past production, numerous problems have been exposed at each stage, such as out-of-tolerance dimensions of the shaft outer diameter, misalignment between the spline hole and the outer diameter, non-parallelism between the axes of the large and small shafts, substandard surface finish, unbalanced process cycles, and low machining efficiency, severely impacting product quality and delivery schedules. Therefore, it is necessary to design a turning fixture and standardized machining method for Z-shaped balance elbows. Utility Model Content

[0004] (a) Technical problems to be solved This utility model proposes a Z-shaped balance elbow turning fixture to solve the technical problems of high processing difficulty, inability to clamp, unstable product quality, and low processing efficiency caused by the irregular eccentric structure, large size, heavy weight, and high precision requirements of the Z-shaped balance elbow.

[0005] (II) Technical Solution To solve the above-mentioned technical problems, this utility model proposes a Z-shaped balanced elbow turning fixture, which includes a flange, a base, a support body, a center, a counterweight, and fastening bolts; wherein... The flange serves as a connecting component between the turning fixture and the lathe. The rear end of the flange is connected to the spindle of the CNC lathe through a central taper hole, and the center position of the front end face is connected to the stepped surface of the rear end face of the chassis through a positioning boss. The chassis serves as the base of the turning fixture. The chassis body has elongated through-slots machined on it, and the center of its front face is fixedly connected to the support body via a locating boss. The support body also has elongated through-slots machined on it to reduce the overall weight of the turning fixture and to prevent interference between the non-machined axis of the Z-shaped balance elbow and the turning fixture. Several sets of fastening bolts are installed on both sides and the top of the elongated through-slots of the support body to secure the non-machined axis of the Z-shaped balance elbow. A counterweight is installed on the front face of the chassis. The rear end of the center mates with the positioning slot on the front end of the support body and is fixed to the support body; during machining, the center and the lathe tailstock center respectively press against the machining shaft of the Z-shaped balance elbow to achieve double-top mounting.

[0006] Furthermore, standard flanges are used.

[0007] Furthermore, the dimensions of the elongated through groove on the support body are the same as those of the elongated through groove on the chassis.

[0008] Furthermore, the centerline of each set of fastening bolts is higher than the non-machined axis of the fixed Z-shaped balance elbow.

[0009] Furthermore, the counterweight consists of multiple fan-shaped counterweight plates. By adjusting the number of counterweight plates, the centrifugal force generated during the processing of different models of Z-shaped balance elbows can be balanced.

[0010] Furthermore, two counterweights are installed on the front end of the chassis.

[0011] Furthermore, the centers of gravity of the two counterweights and the support are evenly distributed at 120°.

[0012] (III) Beneficial Effects This invention proposes a Z-shaped balance elbow turning fixture, which includes a flange, base, support body, center, counterweight, and fastening bolts. The machining method includes rough boring of the end face, inner hole, rough turning of the large shaft, rough turning of the small shaft, finish boring of the end face, inner hole, finish turning of the large shaft, finish turning of the small shaft, milling of the outer shape and drilling, and spline (wire EDM) processes. This invention is applicable to the machining of multiple models and large batches of Z-shaped balance elbow products, ensuring stable and reliable product quality and improving the overall product quality pass rate and machining efficiency. Attached Figure Description

[0013] Figure 1a This is the front view of the Z-shaped balancing elbow structure. Figure 1b This is a side view; Figure 2a This is a front view of the Z-shaped balanced elbow turning fixture structure and the machining of the small shaft according to this utility model. Figure 2b This is a side sectional view; Figure 3a This is a front view of the Z-shaped balanced elbow turning fixture structure and the machining shaft of this utility model. Figure 3bThis is a side sectional view; Figure 4 This is a schematic diagram showing the mounting position of the fastening bolts of the Z-shaped balance elbow turning fixture in this utility model; Figure 5 This is a process diagram of rough boring of the end face and inner hole in this utility model; Figure 6 This is a process diagram of rough machining of the main shaft in this utility model; Figure 7 This is a process diagram of rough machining of the small shaft in this utility model; Figure 8 This is a process drawing of precision boring of the end face and inner hole in this utility model; Figure 9 This is a process diagram of precision machining of the main shaft in this utility model; Figure 10 This is a process diagram of precision machining of the small shaft in this utility model; Figure 11 This is a drawing showing the milling and drilling process in this utility model; Figure 12 This is a process diagram of the wire cutting spline in this utility model. Detailed Implementation

[0014] To make the objectives, contents, and advantages of this utility model clearer, the specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples.

[0015] This embodiment proposes a Z-shaped balanced elbow turning fixture, the overall structure of which is as follows: Figure 2a , 2b As shown in 3a and 3b, it mainly includes flange 1, base 2, support body 3, top 4, counterweight 5, and fastening bolts 6.

[0016] Flange 1 serves as the connecting part between the turning fixture and the lathe. It adopts a standard flange. The rear end of flange 1 is connected to the CNC lathe spindle through a central taper hole. The center position of the front end face is connected to the stepped surface of the rear end face of the chassis 2 through a positioning boss and is fixed with bolts to ensure that the rotation center of the turning fixture is consistent with the lathe spindle.

[0017] The chassis 2 serves as the base of the turning fixture. An elongated through-slot is machined into the chassis body, and its front end face is welded to the support body 3 via a locating boss at its center. The support body 3 also has an elongated through-slot, the same size as the one on the chassis 2, designed to reduce the overall weight of the turning fixture and prevent interference between the non-machining axis of the Z-shaped balance elbow 8 and the turning fixture. Figure 4As shown, several sets of fastening bolts 6 are provided on both sides and top of the elongated through groove of the support body 3 to fix the non-machined shaft of the Z-shaped balance elbow 8. The design of the elongated through groove ensures that Z-shaped balance elbows 8 of different models and sizes can be machined using this turning fixture, realizing multi-purpose use of one fixture. The centerline of each set of fastening bolts 6 is higher than the center distance H of the outer circle of the non-machined shaft of the fixed Z-shaped balance elbow 8. This mounting method ensures that the clamping force of the fastening bolts 6 on the Z-shaped balance elbow is opposite to the centrifugal force, effectively reducing the centrifugal force generated by the rotation of the workpiece.

[0018] Two counterweights 5 are mounted on the front face of the chassis 2 with screws. Each counterweight 5 consists of multiple fan-shaped counterweight plates. By adjusting the number of counterweight plates, the centrifugal force generated during the machining of different models of Z-shaped balance elbows can be balanced. The two counterweights 5 and the center of gravity of the support body 3 are evenly distributed at 120°. The three-point distribution of the support body 3 and the two counterweights 5 ensures smoother workpiece rotation during machining, reduces vibration, and helps improve the outer diameter accuracy and surface finish of the product.

[0019] The rear end of the center point 4 mates with the locating slot on the front end of the support body 3 and is welded to the support body 3. During machining, the center point 4 and the lathe tailstock center point 7 respectively rest on both ends of the machining axis of the Z-shaped balance elbow 8 to achieve double-top mounting. To ensure that the locating cone surface of the center point 4 is coaxial with the lathe spindle, the turning fixture needs to be precision machined on the lathe after welding.

[0020] The Z-shaped balance elbow blank is a die forging. During rough and finish turning of the large and small shafts, the aforementioned Z-shaped balance elbow turning fixture is required to hold the Z-shaped balance elbow. This turning fixture can balance the centrifugal force generated during workpiece rotation, thereby reducing vibration and increasing spindle speed, effectively improving product machining accuracy and cutting speed. The specific machining method includes the following steps: S1. Rough boring of end face and inner hole: such as Figure 5 As shown, this process uses a CNC horizontal boring machine. The end face and inner hole each have a 2mm allowance on one side. The main function of this process is to quickly remove a large amount of material and to make process center holes for rough turning the outer diameter of the large and small shafts. The CNC horizontal boring machine has a 360° rotating worktable, which can realize universal machining in the XOY plane with one setup. This process can machine four end faces and inner holes at one time, ensuring that the center process holes at both ends of the large and small shafts are coaxial and the center lines of the large and small shafts are parallel.

[0021] S2. Rough machining of the main shaft: such as... Figure 6 As shown, this process is performed using a CNC lathe. The outer diameter of the Z-shaped balance elbow workpiece shaft has a single-sided allowance of 1.5mm. The main function of this process is to quickly remove a large amount of material and to provide a process reference for precision boring of the end face and inner hole. Because the center of gravity of the Z-shaped balance elbow is offset from the center of rotation during turning, a special turning fixture with a counterweight 5 is used for clamping in order to balance the centrifugal force, reduce vibration, and increase the spindle speed.

[0022] S3. Rough turning of the small axle: such as Figure 7 As shown, this process is carried out using CNC lathe equipment. The outer circle and end face of the small shaft of the Z-shaped balance elbow workpiece are both left with a single-sided allowance of 1.5mm. The main function of this process is to quickly remove a large amount of material and release the processing stress.

[0023] After rough machining, the large and small shafts form regular outer circles. During precision boring, a V-shaped clamp is used to secure the two shafts more firmly.

[0024] S4. Precision boring of end face and inner hole: such as... Figure 8 As shown, this process uses a CNC horizontal boring machine. The rough turning of the outer diameter of the large shaft is used as the process reference and the mounting and positioning reference. The main function of this process is to process the four end faces and inner holes of the product to the required dimensions, ensuring dimensional accuracy and surface finish. At the same time, it also provides a chamfer for the finish turning of the outer diameters of the large and small shafts.

[0025] S5. Precision-machined main shaft: such as Figure 9 As shown, this process uses CNC lathe equipment to process the outer circle of the Z-shaped balance elbow workpiece shaft to the required dimensions, ensuring dimensional accuracy, geometric accuracy and surface finish. This process uses the chamfer made during precision boring of the inner hole as the mounting and positioning reference, thus ensuring the coaxiality of the outer circle and inner hole of the shaft.

[0026] S6. Precision-machined small shaft: such as Figure 10 As shown, this process uses CNC lathe equipment to process the outer circle of the small shaft of the Z-shaped balance elbow workpiece to the required size, ensuring dimensional accuracy, geometric accuracy and surface finish. This process uses the chamfer made during precision boring of the inner hole as the mounting and positioning reference, thus ensuring the coaxiality of the outer circle of the small shaft and the inner hole and the parallelism of the center lines of the small shaft and the large shaft.

[0027] S7. Milling the outline and drilling: (e.g.) Figure 11 As shown, this process uses a vertical machining center to machine the product's shape and drill holes.

[0028] S8. Broaching spline (wire cut spline): such as... Figure 12 As shown, when the product batch is large, this process generally uses a broaching machine in conjunction with a broach to ensure production efficiency and consistency of spline hole size. When a broach is not available and the batch is small, this process can use a wire EDM machine. This process uses the outer circle of the main shaft as the mounting and positioning reference to ensure the coaxiality of the spline hole and the outer circle of the main shaft.

[0029] At this point, the Z-shaped balance elbow product has completed all processing steps, and subsequent processes such as flaw detection and surface treatment can be carried out.

[0030] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A Z-shaped balanced elbow turning fixture, characterized in that, The Z-shaped balanced elbow turning fixture includes a flange, a chassis, a support body, a center, a counterweight, and fastening bolts; wherein... The flange serves as a connecting component between the turning fixture and the lathe. The rear end of the flange is connected to the spindle of the CNC lathe through a central tapered hole, and the center position of the front end face is connected to the stepped surface of the rear end face of the chassis through a positioning boss. The chassis serves as the base of the turning fixture. An elongated through-slot is machined on the chassis body, and a positioning boss at the center of the front end face is used to fix it to the support body. The support body also has an elongated through-slot to reduce the overall weight of the turning fixture and to prevent interference between the non-machined axis of the Z-shaped balance elbow and the turning fixture. Several sets of fastening bolts are provided on both sides and the top of the elongated through-slot of the support body to fix the non-machined axis of the Z-shaped balance elbow. A counterweight is installed on the front end face of the chassis. The rear end of the tip engages with the positioning slot on the front end of the support body and is fixed to the support body; during machining, the tip and the lathe tailstock tip respectively press against the machining shaft of the Z-shaped balance elbow to achieve double-top mounting.

2. The Z-shaped balanced elbow turning fixture as described in claim 1, characterized in that, The flange used is a standard flange.

3. The Z-shaped balanced elbow turning fixture as described in claim 1, characterized in that, The elongated through groove on the support body has the same dimensions as the elongated through groove on the chassis.

4. The Z-shaped balanced elbow turning fixture as described in claim 1, characterized in that, The centerline of each set of fastening bolts is higher than the non-machined axis of the fixed Z-shaped balance elbow.

5. The Z-shaped balanced elbow turning fixture as described in claim 1, characterized in that, The counterweight consists of multiple fan-shaped counterweight plates. By adjusting the number of counterweight plates, the centrifugal force generated during the processing of different models of Z-shaped balance elbows can be balanced.

6. The Z-shaped balanced elbow turning fixture as described in claim 1, characterized in that, The chassis has two counterweights installed on its front end.

7. The Z-shaped balanced elbow turning fixture as described in claim 6, characterized in that, The two counterweights are evenly distributed at 120° to the center of gravity of the support.

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