Method for calculating force on piston of crank and connecting rod mechanism when piston is idle

Abstract

The present application relates to the field of crank connecting rod, and particularly relates to a force calculation method for a piston of a crank connecting rod mechanism in an idle state, comprising the following steps: S1, equivalent the total force of the piston in the direction of the cylinder axis to the centrifugal force of the piston in the direction of the cylinder axis; S2, based on the centrifugal force, according to the force balance relationship, calculate the connecting rod force and the lateral force of the piston. The present application can calculate the connecting rod force and the lateral force of the piston without reciprocating inertia force, and greatly simplifies the calculation process.

Description

Technical Field

[0001] This invention relates to the field of crank connecting rods, specifically a method for calculating the force on the piston of a crank connecting rod mechanism when it is unloaded. Background Technology

[0002] The crank-connecting rod mechanism is a core component of power machinery such as engines and compressors. It mainly consists of three moving parts: crank, connecting rod, and piston. The crank rotates at a constant speed around the center of the crankshaft, the piston reciprocates along the center line of the cylinder, and the connecting rod connects the piston and crank into a motion system. It converts the reciprocating motion of the piston into the rotational motion of the crankshaft to transmit power.

[0003] Since its establishment, the kinematic and dynamic theories of crank-connecting rod mechanisms have formed a complete system of design and calculation theories. The piston is the core component of the mechanism's reciprocating motion. Since the formation of classical theory, the force analysis of the piston has been based on several forces: gas force (working pressure), reciprocating inertial force, friction, connecting rod force, and piston lateral force. If we disregard the gas force and friction during operation, i.e., under no-load conditions, the connecting rod force and piston lateral force must be calculated based on the piston's reciprocating inertial force, and the calculation process is quite complex. Summary of the Invention

[0004] To avoid and overcome the technical problems existing in the prior art, this invention proposes a motion model for the crank-connecting rod mechanism that is a pure rotational motion, thereby providing a method for calculating the force on the piston of the crank-connecting rod mechanism when unloaded. This invention can calculate the connecting rod force and piston lateral force under no-load conditions without relying on reciprocating inertial forces, greatly simplifying the calculation process.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A method for calculating the force on the piston of a crank-connecting rod mechanism under no-load conditions includes the following steps: S1. The total force on the piston along the cylinder axis is equivalent to the centrifugal force on the piston along the cylinder axis. :

[0006] in, The mass of the piston; This is the vertical distance from the piston pin center to the crankshaft rotation center. The angular velocity of the crank rotation; Where is the crank radius; The crank angle; The length of the link; The swing angle of the connecting rod; S2, Based on centrifugal force Calculate the lateral force on the piston based on the force balance relationship. and linkage force .

[0007] As a further aspect of the present invention: .

[0008] As a further aspect of the present invention: .

[0009] An electronic device is characterized in that it includes a processor, an input device, an output device, and a memory, wherein the processor, the input device, the output device, and the memory are connected in sequence, the memory is used to store a computer program, the computer program includes program instructions, and the processor is configured to call the program instructions to execute the method for calculating the piston force when unloaded in a crank-connecting rod mechanism.

[0010] A readable storage medium, characterized in that the storage medium stores a computer program, the computer program including program instructions, which, when executed by a processor, cause the processor to execute the aforementioned method for calculating the force of a piston under no-load conditions in a crank-connecting rod mechanism.

[0011] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention equates the piston force under no-load conditions to the centrifugal force of the piston on the cylinder axis. Using the centrifugal force as the design input for all subsequent calculations, it is not necessary to calculate the reciprocating inertial force separately to calculate the connecting rod force and piston lateral force, which greatly simplifies the calculation process and corrects the traditional crank-connecting rod mechanism calculation theory system. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the piston force analysis in the crank-connecting rod mechanism of the present invention. Detailed Implementation

[0013] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] Please see Figure 1In this embodiment of the invention, a method for calculating the force on the piston of a crank-connecting rod mechanism under no-load conditions is provided. Through relative motion analysis, the actual physical model of the crank-connecting rod mechanism is essentially a rotary motion. The linear motion of the piston is formed on the basis of the rotary motion and constrained by the linear cylinder, which can be specifically decomposed in the following two steps.

[0015] The first step, assuming there is no cylinder, is that under the action of the driving torque, the crank, connecting rod, and piston form a... (Assuming constant velocity) is a constant angular velocity, with the crank radius... and connecting rod length The piston undergoes uniform rotary motion with a radius equal to the sum of the forces acting on it. The sum of the forces acting on the piston is... , m This is the piston mass.

[0016] The second step involves the presence of a linear cylinder, where the uniformly rotating piston is subjected to a lateral force from the cylinder wall perpendicular to the cylinder axis. This alters the piston's original motion, preventing it from following the crankshaft at a constant speed. It rotates at a speed that is actually at a variable speed. The piston moves along two axes: first, it remains on the cylinder axis; second, it reciprocates along the cylinder axis. Because the piston's position relative to the crankshaft center changes, the centrifugal force acting on the piston increases. This also changes accordingly. The force analysis of the piston in the crank-connecting rod mechanism is as follows: Figure 1 As shown, including centrifugal force Lateral force and linkage force .based on Figure 1 In the force analysis, the calculations in this application are performed with the crankshaft center as the point of origin. The total force on the piston along the cylinder axis (unloaded piston force) is the centrifugal force of the piston along the cylinder axis. :

[0017] in, The mass of the piston; This is the vertical distance from the piston pin center to the crankshaft rotation center. The angular velocity of the crank rotation; Where is the crank radius; The crank angle; The length of the link; The swing angle of the connecting rod; Based on the balance relationship between piston force, connecting rod force, and lateral force:

[0018] according to Figure 1 The constructed physical model of the crank-connecting rod mechanism shows that the piston force under no-load conditions is the centrifugal force of the piston on the cylinder axis. The centrifugal force serves as the design input for all subsequent calculations, so there is no need to calculate the reciprocating inertial force separately, which can greatly simplify the force calculation process.

[0019] Another embodiment of this application is an electronic device.

[0020] The electronic device can be the mobile device itself, or a standalone device that can communicate with the mobile device to receive the collected input signals from it and send the selected target decision behavior to it.

[0021] Electronic devices include one or more processors and memory.

[0022] A processor can be a central processing unit (CPU) or other form of processing unit with data processing and / or instruction execution capabilities, and can control other components in an electronic device to perform desired functions.

[0023] The memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and a processor may execute the program instructions to implement a method for calculating the piston force of a crank-connecting rod mechanism under no-load conditions according to the various embodiments of this application described above.

[0024] In one example, the electronic device may also include input and output devices, which are interconnected via a bus system and / or other forms of connection. For example, the input device may include various devices such as on-board diagnostics (OBD), cameras, industrial cameras, etc. The input device may also include, for example, a keyboard, a mouse, etc. The output device may include, for example, a monitor, speakers, a printer, and communication networks and their connected remote output devices, etc.

[0025] In addition, depending on the specific application, electronic devices may include any other suitable components.

[0026] Another embodiment of this application may be a computer program product, which includes computer program instructions that, when executed by a processor, cause the processor to perform the calculation steps described in the above-described method for calculating the piston force of a crank-connecting rod mechanism under no-load conditions, according to various embodiments of this application.

[0027] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of this application. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0028] Furthermore, embodiments of this application may also be computer-readable storage media storing computer program instructions that, when executed by a processor, cause the processor to perform a method for calculating the force on a piston of a crank-connecting rod mechanism under no-load conditions, as described in this specification.

[0029] The computer-readable storage medium may be any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may, for example, include, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: electrical connections having one or more wires, portable disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0030] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0031] The block diagrams of devices, apparatuses, devices, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

Claims

1. A method for calculating the force on the piston of a crank-connecting rod mechanism under no-load conditions, characterized in that, Includes the following steps: S1. The total force on the piston along the cylinder axis is equivalent to the centrifugal force on the piston along the cylinder axis. : in, The mass of the piston; This is the vertical distance from the piston pin center to the crankshaft rotation center. The angular velocity of the crank rotation; Where is the crank radius; The crank angle; The length of the link; The swing angle of the connecting rod; S2, Based on centrifugal force Calculate the lateral force on the piston based on the force balance relationship. and linkage force .

2. The method for calculating the piston force under no-load conditions in a crank-connecting rod mechanism according to claim 1, characterized in that, 。 3. The method for calculating the piston force under no-load conditions in a crank-connecting rod mechanism according to claim 1, characterized in that, 。 4. An electronic device, characterized in that, The system includes a processor, an input device, an output device, and a memory, which are connected in sequence. The memory is used to store a computer program, which includes program instructions. The processor is configured to call the program instructions to execute a method for calculating the piston force under no-load conditions in a crank-connecting rod mechanism as described in any one of claims 1 to 3.

5. A readable storage medium, characterized in that, The storage medium stores a computer program, which includes program instructions that, when executed by a processor, cause the processor to perform a method for calculating the piston force under no-load conditions in a crank-connecting rod mechanism as described in any one of claims 1 to 3.

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