Engine cylinder liner grinding fixture for unmanned aerial vehicle

Abstract

The utility model discloses an unmanned plane engine cylinder liner grinding clamping fixture belongs to mechanical processing fixture technical field, this fixture mainly includes core axle, inflation tire, sliding axle, clamping washer, connecting ring, nut and lock nut. The core axle is equipped with the outer conical surface, and is matched with the taper hole surface of inflation tire inner hole, pushes the sliding axle and clamping washer axial movement through rotating nut, and then forces inflation tire to move along the core axle taper surface and generates radial elastic expansion, thereby realizes and the zero clearance of cylinder liner inner hole expands tightly, and the reverse rotation nut is through connecting ring and draws sliding axle, makes inflation tire reset and loosens work piece. The utility model's core lies in using inflation tire structure to provide integral type inner support for thin wall cylinder liner, effectively solved the technical problem of traditional double top disc mode positioning having clearance, workpiece easy deformation, has positioning precision height, anti -deformation ability is strong, and the advantage such as convenient operation, especially suitable for high -precision unmanned plane engine cylinder liner's outer circle grinding processing.

Description

Technical Field

[0001] This utility model relates to the field of tooling and fixture technology, and in particular to a grinding fixture for engine cylinder liners of unmanned aerial vehicles. Background Technology

[0002] UAV engine cylinder liners are precision thin-walled parts, with their entire outer diameter serving as a mounting surface. They have a long machining length and extremely high requirements for dimensional tolerances, surface roughness, and geometric tolerances. Currently, the outer diameter grinding of these cylinder liners commonly employs a double-end positioning plate and double-top method for positioning and clamping. This traditional method requires matching the outer diameter of the positioning plate with the inner diameter of the cylinder liner to meet positioning accuracy requirements, which has several inherent drawbacks: First, the positioning plate itself requires extremely high manufacturing precision, resulting in a long machining cycle and high manufacturing costs; second, a single cylinder liner model often requires multiple sets of positioning plates of different sizes to accommodate the inner diameter tolerances, complicating production preparation; more importantly, this fit clearance cannot be completely eliminated, inherently limiting further improvements in positioning accuracy. Furthermore, UAV cylinder liners have thin walls and typically feature multiple weight-reduction or functional notches in the radial and end faces, resulting in poor structural rigidity. When using a support method that clamps the inner hole at both ends, the middle of the cylinder liner is suspended in the air. Under the action of grinding force, it is prone to elastic deformation, resulting in out-of-tolerance dimensional and positional tolerances such as roundness and cylindricity, making it impossible to guarantee high-precision machining requirements. Therefore, existing technology has become a technical bottleneck restricting the manufacturing of cylinder liners for high-performance UAV engines. Utility Model Content

[0003] The purpose of this invention is to provide a grinding fixture for engine cylinder liners of unmanned aerial vehicles, which solves the problems of fit clearance and workpiece deformation in the traditional double top plate positioning method.

[0004] This utility model is achieved using the following technical solution: a grinding fixture for engine cylinder liners of unmanned aerial vehicles, characterized in that it includes a mandrel, an expansion tire sleeved on the mandrel, and a driving mechanism for driving the expansion tire to move axially along the mandrel to radially expand the expansion tire; the mandrel is provided with a first mating conical surface, and the inner hole of the expansion tire is provided with a second mating conical surface that matches the first mating conical surface; the driving mechanism acts on one end of the expansion tire to push or pull the expansion tire so that its first mating conical surface and second mating conical surface are tightly fitted or separated, thereby realizing the expansion of the outer circle of the expansion tire to the inner hole of the cylinder liner workpiece.

[0005] Furthermore, the first mating conical surface is an outer conical surface located in the middle section of the mandrel, and the second mating conical surface is a conical hole surface located in the inner hole of the expansion tire.

[0006] Furthermore, the expansion tire is a sleeve structure made of elastic material, and its outer circle is designed as a cylindrical surface that fits with the inner hole of the UAV engine cylinder liner with zero clearance.

[0007] Furthermore, the drive mechanism includes a nut, a sliding shaft, and a clamping washer; the nut is screwed onto the thread at one end of the mandrel; the sliding shaft is sleeved on the mandrel and can slide axially; the clamping washer is disposed between the end of the expanded tire and the sliding shaft; rotating the nut can push the sliding shaft to move axially, thereby transmitting the axial thrust to the expanded tire through the clamping washer.

[0008] Furthermore, the drive mechanism also includes a connecting ring, which is sleeved on the spindle and located between the nut and the sliding shaft. The nut indirectly pushes the sliding shaft by pushing the connecting ring.

[0009] Furthermore, the sliding shaft and the clamping washer are fixedly connected by screws.

[0010] Furthermore, it also includes a locking nut, which is screwed onto the mandrel and close to the nut, and is used to lock the nut after clamping to prevent it from rotating and loosening.

[0011] Furthermore, both ends of the mandrel are provided with center holes for supporting the machine tool center.

[0012] The present invention provides a grinding fixture for engine cylinder liners of unmanned aerial vehicles, which has the following advantages: This invention employs a positioning method that uses a zero-clearance fit between the expansion pad and the inner hole of the workpiece, fundamentally eliminating the positioning error caused by the fit clearance of traditional positioning discs, and providing an excellent reference for high-precision grinding.

[0013] The expansion structure provides integral support for the entire inner length of the thin-walled cylinder liner, greatly enhancing the rigidity of the workpiece and effectively suppressing the elastic deformation of the workpiece under the action of grinding force and clamping force, thus ensuring the roundness, cylindricity and other dimensional and positional tolerances after machining.

[0014] This fixture abandons the high-precision matching positioning plate and is mainly composed of standard or easy-to-process parts such as mandrel, expansion tire, and nut. It has a lightweight structure and significantly reduces manufacturing costs and cycle time.

[0015] The workpiece can be clamped and released by manually tightening the nut. The action is reliable, the operation is simple and intuitive, which reduces the skill requirements of the operator and improves the clamping efficiency.

[0016] By changing the expansion tires of different outer diameters, this fixture can be adapted to the processing of cylinder liners of different models within a certain size range, thereby enhancing the utilization rate and flexibility of the equipment. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 A side sectional view of a jig for grinding cylinder liners of an unmanned aerial vehicle (UAV) engine; In the diagram, 1-mandrel, 2-expansion tire, 3-sliding shaft, 4-clamping washer, 5-connecting ring, 6-nut, 7-locking nut, 8-cylinder liner, 9-screw. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention. Example

[0021] like Figure 1 As shown, this embodiment provides a grinding fixture for engine cylinder liners of unmanned aerial vehicles, comprising a mandrel 1, an expansion tire 2, a sliding shaft 3, a clamping washer 4, a connecting ring 5, a nut 6, a locking nut 7, and a screw 9, used to clamp the workpiece cylinder liner 8.

[0022] The mandrel 1 is the core support component of the fixture. Its left end has a standard center hole for supporting the machine tool center, and its right end has an external thread for assembling the nut 6 and locking nut 7. The middle section of the mandrel 1 is designed with a precision outer conical surface to mate with the inner conical surface of the expansion sleeve 2. The expansion sleeve 2 is an elastic sleeve structure; its inner hole is a conical hole matching the mandrel 1, and its outer circle is a cylindrical surface, providing a zero-clearance fit with the inner hole of the cylinder liner 8. The right end face of the expansion sleeve 2 contacts the clamping washer 4, and the left end face is limited by the sliding shaft 3.

[0023] The sliding shaft 3 has a stepped shaft structure. Its left end is fixedly connected to the clamping washer 4 by screw 9, and its right end extends into the inner hole of the connecting ring 5. The clamping washer 4 is a ring-shaped part, with its left side tightly attached to the right end face of the expansion tire 2, and its right side connected to the sliding shaft 3 by screw 9. The connecting ring 5 is sleeved on the mandrel 1, with its left end connected to the right end of the sliding shaft 3 and its right end connected to the nut 6. The nut 6 is screwed onto the right end thread of the mandrel 1, and can be rotated to push the connecting ring 5 to move axially. The locking nut 7 is assembled on the right side of the nut 6 to lock the entire mechanism after clamping, preventing loosening during processing.

[0024] The clamping process of the fixture is as follows: First, the cylinder liner 8 is fitted onto the outside of the expansion tire 2. The nut 6 is rotated to move it to the left, pushing the connecting ring 5 and the sliding shaft 3 to move to the left. Since the sliding shaft 3 and the clamping washer 4 are fixedly connected by the screw 9, the clamping washer 4 moves to the left and pushes the expansion tire 2 to slide to the left along the conical surface of the mandrel 1. Under the action of the conical surface, the expansion tire 2 undergoes radial elastic expansion, making its outer circle and the inner hole of the cylinder liner 8 achieve zero clearance expansion. Finally, the locking nut 7 is tightened to prevent the nut 6 from rotating and loosening during processing. At this time, the outer circle can be ground by tightening the center holes at both ends of the mandrel 1.

[0025] The clamping process is as follows: First, loosen the locking nut 7, then rotate the nut 6 in the opposite direction to move it to the right. This pushes the sliding shaft 3 and clamping washer 4 to the right via the connecting ring 5. The clamping washer 4 drives the expanding tire 2 to move to the right, causing it to disengage from the conical surface of the mandrel 1. Under its own elastic restoring force, the expanding tire 2 contracts radially, thus separating from the inner hole of the cylinder liner 8, thereby releasing the workpiece.

[0026] This fixture achieves full contact with the workpiece's inner bore through an integral expanding structure, overcoming the problems of the cylinder liner being suspended in the middle and prone to deformation in traditional double-top-plate positioning methods. Its manual clamping mechanism is lightweight and easy to operate, significantly improving the grinding accuracy and stability of thin-walled, multi-notch UAV cylinder liners, while reducing tooling manufacturing costs and production cycle.

[0027] The above embodiments describe the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Modifications and variations made by those skilled in the art without departing from the spirit and scope of this utility model should be protected within the scope of the appended claims.

Claims

1. A grinding fixture for engine cylinder liners of unmanned aerial vehicles, characterized in that, The device includes a mandrel (1), an expansion tire (2) sleeved on the mandrel (1), and a drive mechanism for driving the expansion tire (2) to move axially along the mandrel (1) to cause the expansion tire (2) to expand radially; the mandrel (1) is provided with a first mating conical surface, and the inner hole of the expansion tire (2) is provided with a second mating conical surface that matches the first mating conical surface; the drive mechanism acts on one end of the expansion tire (2) to push or pull the expansion tire (2) so that its first mating conical surface and second mating conical surface are tightly fitted or separated, thereby realizing the expansion or loosening of the outer circle of the expansion tire (2) against the inner hole of the cylinder liner workpiece (8).

2. The jig for grinding cylinder liners of an unmanned aerial vehicle (UAV) engine according to claim 1, characterized in that, The first mating conical surface is an outer conical surface located in the middle section of the mandrel (1), and the second mating conical surface is a conical hole surface located in the inner hole of the expansion tire (2).

3. The jig for grinding cylinder liners of an unmanned aerial vehicle (UAV) engine according to claim 1, characterized in that, The expansion tire (2) is a sleeve structure made of elastic material, and its outer circle is designed as a cylindrical surface that fits with the inner hole of the unmanned aerial vehicle engine cylinder liner with zero clearance.

4. A grinding fixture for engine cylinder liners for unmanned aerial vehicles according to claim 1, characterized in that, The drive mechanism includes a nut (6), a sliding shaft (3), and a clamping washer (4); the nut (6) is screwed onto the thread at one end of the spindle (1); the sliding shaft (3) is sleeved on the spindle (1) and can slide axially; the clamping washer (4) is located between the end of the expansion tire (2) and the sliding shaft (3); rotating the nut (6) can push the sliding shaft (3) to move axially, and then transmit the axial thrust to the expansion tire (2) through the clamping washer (4).

5. A grinding fixture for engine cylinder liners of unmanned aerial vehicles according to claim 4, characterized in that, The drive mechanism also includes a connecting ring (5), which is sleeved on the spindle (1) and located between the nut (6) and the sliding shaft (3). The nut (6) indirectly pushes the sliding shaft (3) by pushing the connecting ring (5).

6. A grinding fixture for engine cylinder liners of unmanned aerial vehicles according to claim 4, characterized in that, The slide shaft (3) and the clamping washer (4) are fixedly connected by screws (9).

7. A grinding fixture for engine cylinder liners of unmanned aerial vehicles according to claim 4, characterized in that, It also includes a locking nut (7), which is screwed onto the spindle (1) and close to the nut (6) to lock the nut (6) after clamping to prevent it from rotating loose.

8. A grinding fixture for engine cylinder liners of unmanned aerial vehicles according to claim 1, characterized in that, Both ends of the mandrel (1) are provided with center holes for supporting the machine tool tip.

Images