A rotary piston device

Abstract

The application discloses a self-rotating piston device, which comprises a piston body, a sealing and lubricating ring arranged on the outer circle of the piston body, two oblique sawtooth rings arranged at the front end of the piston body, and a movable counterweight arranged between the two oblique sawtooth rings. The sawteeth of the two oblique sawtooth rings are opposite, oblique and opposite, and staggered. The counterweight is elastically connected with the piston body. The front and rear ends of the counterweight are provided with sawteeth matched with the two oblique sawtooth rings respectively. Under normal state, the counterweight is engaged with the inner oblique sawtooth ring, and the piston completes the stop process of the stroke. The front end of the counterweight is in contact with the oblique sawtooth ring at the front end, and rotates upward by an angle and is engaged with the oblique sawtooth ring at the front end. After the counterweight is reset, the counterweight is in contact with the inner oblique sawtooth ring under the action of the elastic force, is engaged with the inner oblique sawtooth ring and rotates, and completes the rotation of one tooth pitch. After multiple strokes are completed, when the rotating torque generated by the counterweight is greater than the friction resistance of the piston body relative to the cylinder body, the counterweight drives the piston to rotate. The application can achieve the purpose that the sealing ring is uniformly stressed.

Description

Technical Field

[0001] This invention belongs to the field of piston assemblies, and specifically relates to a self-rotating piston device. Background Technology

[0002] Currently, pistons are all fixed in a reciprocating motion within the cylinder. For vertically moving pistons, the uniformity of the piston's friction surface has little impact. However, for pistons with significant weight that move horizontally, their own weight inevitably leads to uneven stress on the sealing rings, resulting in a significant reduction in their lifespan and a shortened maintenance cycle. Especially for aircraft carrier catapults with a power stroke of nearly 100 meters, the piston's weight and travel distance are considerable. Extending the lifespan of the sealing rings and minimizing the frequency of replacement and maintenance are key to improving catapult stability and reducing failure rates. Summary of the Invention

[0003] The purpose of this invention is to provide a self-rotating piston device that achieves a single ejection of the piston at a certain angle by rotating a counterweight, thereby realizing a uniform rotational change in the wear position of the sealing ring and achieving uniform force on the sealing ring. This solves the problem of seal failure caused by uneven force on the sealing ring when the piston moves horizontally.

[0004] The technical solution for achieving the objective of this invention is as follows:

[0005] A self-rotating piston device includes a piston body, a sealing ring disposed on the outer circumference of the piston body, and two oblique serrated rings provided at the front end of the piston body, wherein the serrations of the two oblique serrated rings are opposite to each other, obliquely opposite and staggered.

[0006] A counterweight is provided between the two oblique sawtooth rings, and the counterweight is elastically connected to the piston body.

[0007] The counterweight has serrations at both ends that engage with two oblique serrated rings.

[0008] Under normal conditions, the counterweight engages with the inner serrated ring, the piston completes the stroke and stops, the counterweight moves forward and engages with the front serrated ring, rotates upward at an angle and engages with the front serrated ring.

[0009] After the counterweight is reset, it contacts and engages with the inner oblique sawtooth ring under the action of elastic force, rotates and meshes with the inner oblique sawtooth, completing a rotation of one tooth pitch; after multiple strokes, when the rotational torque generated by the counterweight is greater than the frictional resistance of the piston body relative to the cylinder, the torque generated by the counterweight drives the piston to rotate.

[0010] Compared with the prior art, the significant advantages of the present invention are:

[0011] 1. After the piston completes each stroke and stops, its counterweight will automatically rotate a certain angle (i.e., one tooth pitch rotation degree). When the rotational torque of the counterweight reaches a certain value, the piston will automatically rotate during the reset process due to the rotational torque, thereby changing the position of the sealing ring on the piston, achieving the goal of uniform wear of the sealing ring and extending its service life, and thus extending the maintenance cycle of the catapult.

[0012] 2. It allows for the replacement of the sealing ring without disassembling the cylinder, improving maintenance efficiency and reducing maintenance costs.

[0013] 3. The application of lightweight materials helps to improve the conversion of catapult power and reduce the power of the stopper;

[0014] 4. Graphite-impregnated sealing and lubricating rings are suitable for high-speed and high-pressure friction conditions.

[0015] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0016] Figure 1 Overall structural diagram of the self-rotating piston device.

[0017] Figure 2 This is an exploded view of a rotating piston device.

[0018] Figure 3 This is a front view of the rotary piston assembly.

[0019] Figure 4 This is a side view of the rotary piston assembly.

[0020] Figure 5 This is a rear view of the rotary piston assembly.

[0021] Figure 6 This is a structural diagram of the fixed frame.

[0022] Figure 7 Connection diagram of the fixed bracket and piston body. Detailed Implementation

[0023] Combination Figures 1-7 The self-rotating piston device of this embodiment includes a piston body 1, a graphite impregnated sealing and lubricating ring 2, a fastening screw 3, a spring pressure plate 4, a counterweight 5, an energy-absorbing rubber 6, a right oblique serrated ring 7, and a left oblique serrated ring 8.

[0024] The counterweight 5 is fixed to one end of the spring plate 4, and the other end of the spring plate 4 is fixed to the center of the front end of the piston body 1 by a fastening screw 3 (equivalent to being fitted onto a stud, the fixing method is that it can only rotate and cannot move axially). The front end of the piston body 1 is fixed with a right oblique serrated ring 7 and a left oblique serrated ring 8. The counterweight 5 is located between the right oblique serrated ring 7 and the left oblique serrated ring 8. The front and rear ends of the counterweight 5 are provided with serrations, which cooperate with the right oblique serrated ring 7 and the left oblique serrated ring 8 respectively. The right oblique serrated ring 7 and the left oblique serrated ring 8 are offset by a certain angle. In this embodiment, the right oblique serrated ring 7 and the left oblique serrated ring 8 are offset by a certain angle (the angle is about half of the tooth pitch). Under normal conditions, the spring plate 4 keeps the counterweight 5 in contact with the left oblique serrated ring 8. When the piston is stopped, because the stopping acceleration force is greater than the elastic force of the spring plate 4, the counterweight 5 is subjected to impact pressure and contacts the right oblique serrated ring 7, and rotates under the action of the tooth surface to form full contact. When the piston stops (that is, the impact acceleration is less than the elastic force of the spring plate 4), the counterweight 5 rebounds under the action of the spring plate 4 and contacts the left oblique serrated ring 8. Under the action of the tooth surface, it completes a certain angle of rotation. Thus, one stroke is completed, and the counterweight 5 completes a rotation angle change of one tooth pitch on the left oblique serrated ring 8.

[0025] The piston body 1 has a fixed frame at its rear end for rotating connection of the traction rope. When the piston moves inside the cylinder, it pulls the traction rope to traction the towing vehicle, thereby completing the catapult launch of the carrier-based aircraft. When the piston completes its traction work, it decelerates under the action of the stop mechanism and may rebound during the stopping process. Therefore, an energy-absorbing rubber 6 is provided at the rear end of the piston body 1 to prevent the traction rope from directly impacting the rear end of the piston body 1.

[0026] The fixed frame has a traction rope hole 1-1 at its center for the traction rope to pass through and connect to the anchor end of the traction rope, achieving rotation-free constraint. The front end has a bolt hole 1-2 for fixing the fastening screw 3. The piston body 1 has multiple welding holes 1-3 and 1-4 at its front end, serving as welding holes for the right oblique sawtooth ring 7 and the left oblique sawtooth ring 8. The front end also has a ring of perforated holes 1-5 to reduce weight. The outer circumference of the piston body 1 has multiple sealing grooves 1-6 for installing graphite-impregnated sealing lubrication rings 2. The fixed frame has multiple ribs 1-7 for connecting the traction rope hole 1-1 to the piston body 1.

[0027] The sealing grooves 1-6 are spiral grooves. The graphite-impregnated sealing lubricating ring 2 is wound around the sealing grooves 1-6 and fixed at both ends with screws. When it is worn and needs to be replaced, simply align the sealing groove with the pressure relief hole of the cylinder, remove the screws from the pressure relief hole, and remove the old graphite-impregnated sealing lubricating ring 2. When replacing, first fix one end of the graphite-impregnated sealing lubricating ring 2 in the sealing groove 1-6, then rotate the piston to wind the graphite-impregnated sealing lubricating ring 2 around the sealing groove 1-6 and fix the other end. This allows the sealing lubricating ring to be replaced without disassembling the cylinder, improving maintenance efficiency.

[0028] To improve the stability of the piston during high-speed movement, the ratio of piston length to diameter should be no less than 1.5, and the point of force should be located at the bottom of the piston, as the front section is prone to wobbling when subjected to force.

[0029] In its initial state, due to gravity, counterweight 5 is located at the lower end of the piston, with no rotational torque. When the rear end of the piston is propelled forward in the cylinder by high-pressure gas, it drives the traction rope to pull the tractor, completing the catapult launch of the carrier-based aircraft. After one catapult launch, the piston enters the deceleration phase through the cylinder pressure relief hole at a certain speed and stops under the action of the stop mechanism. Due to the impact force (inertia), counterweight 5 continues to move forward. The serrated front end of counterweight 5 contacts and engages with the right oblique serrated ring 7, rotating upwards at an angle to form a complete engagement. Similarly, after counterweight 5 returns to its original position, it contacts and engages with the left oblique serrated ring 8 under the action of spring pressure plate 4, rotating at a certain angle to form a complete engagement. Thus, after one stroke, counterweight 5 completes one tooth pitch of travel on the left oblique serrated ring 8. This process is repeated. After multiple ejections, the counterweight 5 rotates upwards several times, gradually increasing the rotational torque of the counterweight relative to the piston body 1. When the rotational torque generated by the counterweight 5 exceeds the frictional resistance of the piston body 1 relative to the cylinder, the counterweight 5 begins to rotate at an angle, causing the entire piston to rotate. In subsequent ejection processes, the piston body 1 rotates once with each ejection. In this way, the piston continuously rotates during the reciprocating ejection motion, thereby achieving uniform wear of the sealing ring.

[0030] This invention addresses the problem of uneven wear caused by inconsistent force and positional change of the sealing ring during horizontal piston movement. The principle involves designing an eccentric counterweight on the piston. With each reciprocating motion, the counterweight rotates 6 degrees (one tooth pitch). This deflection imparts a certain rotational torque to the piston. When this torque reaches a certain value, the piston rotates a certain angle during its stroke, the angle of which is related to the frictional resistance of the lubricating sealing ring. This continuous rotation of the piston during its ejection reciprocating motion achieves uniform seal wear, extending seal replacement intervals and reducing maintenance frequency and costs.

[0031] This invention adds an eccentric counterweight to the piston. Through mechanism design, the eccentric counterweight rotates in a certain direction between the rack and pinion during impact vibration. The rotation of the counterweight applies a certain eccentric torque (rotational torque) to the piston. When this torque exceeds the frictional torque of the piston's sealing lubrication ring, the piston will rotate during its reciprocating motion. This achieves a change in the position of the seal ring's wear due to gravity, resulting in uniform wear of the seal ring.

[0032] Because the piston is mechanically designed to withstand axial forces and only bears the torque of its own rotation, the structural stress is not complex. To reduce weight, the piston uses lightweight alloy or composite materials, requiring an end pressure greater than 6 MPa and a certain safety factor. Furthermore, weight reduction measures are implemented in the piston structure, such as creating openings to reduce weight while meeting load-bearing requirements. A lighter piston improves the efficiency of ejection power conversion and helps reduce the power consumption of the stop mechanism.

[0033] To reduce the influence of the traction rope on the piston rotation, the connection between the traction rope and the traction rope hole 1-1 is a plug-in end anchor, meaning that the traction rope anchor can rotate radially but cannot move axially.

Claims

1. A self-rotating piston device, comprising a piston body and a sealing ring disposed on the outer circumference of the piston body, characterized in that, The piston body has two oblique serrated rings at the front end, with the serrations of the two oblique serrated rings facing each other, at opposite angles and staggered. A counterweight is provided between the two oblique sawtooth rings, and the counterweight is elastically connected to the piston body. The counterweight is fixed to one end of the spring plate, and the other end of the spring plate is fixed to the center of the front end of the piston body; the spring plate can only rotate and cannot move axially. The counterweight has serrations at both ends that engage with two oblique serrated rings. Under normal conditions, the counterweight engages with the inner serrated ring, the piston completes the stroke and stops, the counterweight moves forward and engages with the front serrated ring, rotates upward at an angle and engages with the front serrated ring. After the counterweight is reset, it contacts and engages with the inner oblique sawtooth ring under the action of elastic force, rotates and meshes with the inner oblique sawtooth, completing a rotation of one tooth pitch; after multiple strokes, when the rotational torque generated by the counterweight is greater than the frictional resistance of the piston body relative to the cylinder, the torque generated by the counterweight drives the piston to rotate.

2. The self-rotating piston device according to claim 1, characterized in that, The piston body has a fixed frame at its rear end for rotating connection of the traction rope.

3. The self-rotating piston device according to claim 2, characterized in that, The piston body has an energy-absorbing rubber at its rear end to prevent the traction rope from directly impacting the piston body.

4. The self-rotating piston device according to claim 1, characterized in that, The piston body has multiple welding holes at its front end for welding two oblique sawtooth rings.

5. The self-rotating piston device according to claim 1, characterized in that, The piston body has a hollow hole at its front end.

6. The self-rotating piston device according to claim 1, characterized in that, The sealing ring is a graphite-impregnated sealing and lubricating ring.

7. The self-rotating piston device according to claim 1, characterized in that, The length-to-diameter ratio of the piston device is not less than 1.

5.

8. The self-rotating piston device according to claim 1, characterized in that, The sealing ring is wound around the sealing groove on the outer circumference of the piston body. The sealing groove is a spiral groove, and the two ends of the sealing ring are fixed in the sealing groove by fasteners.

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