Method, system and excavator for preventing bucket arm from sucking air when rotating

Abstract

The present invention discloses a method, system, and excavator for preventing air from being sucked into the bucket arm during excavator slewing. The method comprises: collecting pilot pressure values ​​for various excavator movements; determining the current excavator movement type based on the collected pilot pressure values; and controlling the opening of the bucket arm selector valve based on the current excavator movement type and the operating pressure of the hydraulic system. By controlling the opening of the bucket arm selector valve, the present invention can effectively prevent air from being sucked into the bucket arm during excavator slewing.

Description

Technical Field

[0001] The present invention belongs to the technical field of excavators, and in particular relates to a method, a system and an excavator for preventing a bucket arm from being sucked into space when the excavator is rotating. Background Art

[0002] In the prior art, the main valve of the excavator is provided with a rotary priority valve. When the excavator rotates and retracts the boom at the same time, the large rotary flow demand can easily cause insufficient boom retraction flow, which in turn leads to the problem of boom retraction air absorption during the combined action of rotation and boom retraction. Summary of the Invention

[0003] In order to solve the deficiencies in the prior art, the present invention provides a method, system and excavator for preventing the bucket arm from absorbing air when the excavator rotates, which can effectively avoid the problem of the bucket arm absorbing air when the excavator rotates.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] In a first aspect, a method is provided for preventing air from being sucked into the boom when an excavator is rotating, comprising: collecting pilot pressure values ​​of various actions of the excavator; judging the current action type of the excavator based on the collected pilot pressure values; and controlling the opening of the boom selection valve based on the current action type of the excavator and the working pressure of the hydraulic system to prevent air from being sucked into the boom when the excavator is rotating.

[0006] Furthermore, the opening of the boom selection valve is controlled according to the current action type of the excavator and the working pressure of the hydraulic system, including: when the working pressure of the hydraulic system is lower than the set first limit value, the opening limit value of the boom selection valve is determined according to the swing pilot pressure value, so that the opening of the boom selection valve is less than the opening limit value of the boom selection valve.

[0007] Furthermore, the opening of the boom selection valve is controlled according to the current action type of the excavator and the working pressure of the hydraulic system, and it also includes: when the boom and the rotation move at the same time, the initial value a of the boom selection valve opening coefficient and the rotation action coefficient s are determined according to the boom retraction handle pilot signal, and the boom selection valve opening limit value coefficient b is determined according to the rotation action coefficient s, and the initial value a of the boom selection valve opening coefficient and the boom selection valve opening limit value coefficient b are compared to obtain the opening coefficient c of the boom selection valve, specifically: if a≤b, then c=a, otherwise c=b.

[0008] Furthermore, the boom selection valve opening limit value coefficient b is linearly negatively correlated with the rotation pilot signal, that is, when the rotation action coefficient s is in the range of 0% to 100%, the corresponding boom selection valve opening limit value coefficient b is 1 to x, where the value range of x is 0 to 1, specifically: b = s*x-s+1.

[0009] On the second aspect, a system is provided for preventing air from being sucked into the boom when the excavator rotates, comprising: a data acquisition module, including a plurality of pilot pressure sensors installed at set positions of the excavator, for collecting pilot pressure values ​​of various actions of the excavator; an action type judgment module, for judging the current action type of the excavator based on the collected pilot pressure values; a boom selection valve opening control module, for controlling the opening of the boom selection valve based on the current action type of the excavator and the working pressure of the hydraulic system, so as to prevent air from being sucked into the boom when the excavator rotates.

[0010] According to a third aspect, an excavator is provided, comprising: a plurality of pilot pressure sensors installed at set positions of the excavator, wherein the plurality of pilot pressure sensors are electrically connected to a controller respectively; the controller is electrically connected to a main pump solenoid valve and a boom selection valve solenoid valve respectively; and the controller is configured to execute the method according to the first aspect for preventing air from being sucked into the boom when the excavator rotates.

[0011] Compared with the prior art, the present invention has the following beneficial effects: the present invention collects the pilot pressure values ​​of each action of the excavator; determines the current action type of the excavator based on the collected pilot pressure values; controls the opening of the boom selection valve based on the current action type of the excavator and the working pressure of the hydraulic system, thereby effectively avoiding the problem of air being sucked into the boom when the excavator rotates. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of a control flow of a method for preventing air from being sucked into the bucket arm during rotation of an excavator, provided by an embodiment of the present invention;

[0013] Figure 2 The present invention provides a block diagram of the structural principles of a system for preventing air from being sucked into the bucket arm during rotation of an excavator. DETAILED DESCRIPTION

[0014] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0015] Example 1:

[0016] A method for preventing air from being sucked into the bucket arm when an excavator is rotating, comprising: collecting pilot pressure values ​​of various actions of the excavator; determining the current action type of the excavator based on the collected pilot pressure values; and controlling the opening of a bucket arm selection valve based on the current action type of the excavator and the working pressure of the hydraulic system to prevent air from being sucked into the bucket arm when the excavator is rotating.

[0017] like Figure 1As shown, the controller determines the rotation and boom movements through the pilot pressure values ​​detected by the pilot pressure sensors of the excavator's various movements. The control system determines whether the corresponding boom and rotation are moving and the corresponding movement selection valve opening through the pilot pressure values ​​of the pilot pressure sensors of the excavator's movements. When the hydraulic system working pressure is lower than the set first limit value, the opening limit value of the boom selection valve is determined according to the rotation pilot pressure value, so that the opening of the boom selection valve is less than the opening limit value of the boom selection valve, thereby limiting the return oil volume of the boom retraction hydraulic oil circuit, increasing the back pressure, and increasing the regeneration amount.

[0018] When the excavator boom and rotation move simultaneously, the control system determines the initial value a of the boom selection valve opening coefficient and the rotation action coefficient s according to the boom retraction handle pilot signal, and determines the boom selection valve opening limit value coefficient b according to the rotation action coefficient s. The initial value a of the boom selection valve opening coefficient and the boom selection valve opening limit value coefficient b are compared to obtain the boom selection valve opening coefficient c, specifically: if a≤b, then c=a, otherwise c=b.

[0019] The first limit of the hydraulic system working pressure refers to the arm flow limit when the hydraulic system working pressure enters the boom lifting action when it is lower than a certain pressure. When the pressure is higher than this limit (such as in the excavation state), there is no limit on the arm flow.

[0020] The boom selection valve opening limit value coefficient b is linearly negatively correlated with the rotary pilot signal, that is, when the rotary action coefficient s is in the range of 0% to 100%, the corresponding boom selection valve opening limit value coefficient b is 1 to x, where the value range of x is 0 to 1. The specific value can be determined during system debugging, that is, b = s*x-s+1.

[0021] The control process of the present invention is as follows: after the excavator is started, the action of the whole machine is judged by the pressure value of the pilot pressure sensor to determine whether the corresponding action occurs. When the pilot pressure value is greater than or equal to 3 bar, the controller receives the user's customized alarm information and selects the corresponding alarm form or no alarm. When the pilot pressure is less than 3 bar, the controller determines that the excavator has no action.

[0022] The present invention prevents cavitation during arm retraction by limiting the opening of the arm selector valve during swinging. The opening limit of the selector valve core for arm retraction is linearly and negatively correlated with the swing pilot handle signal. Under light loads, limiting the arm selector valve opening reduces flow to the arm. Under heavy loads, removing the arm selector valve restriction reduces pressure loss and thus prevents increased fuel consumption. The present invention prevents cavitation by allowing the arm to retract simultaneously during swinging.

[0023] Example 2:

[0024] Based on the method for preventing air from being sucked into the bucket arm during rotation of an excavator as described in the first embodiment, this embodiment provides a system for preventing air from being sucked into the bucket arm during rotation of an excavator, comprising:

[0025] The data acquisition module includes several pilot pressure sensors installed at set positions on the excavator to collect the pilot pressure values ​​of each action of the excavator;

[0026] An action type judgment module is used to judge the current action type of the excavator based on the collected pilot pressure value;

[0027] The arm selection valve opening control module is used to control the opening of the arm selection valve according to the current action type of the excavator and the working pressure of the hydraulic system, so as to prevent the arm from being sucked into the air when the excavator rotates.

[0028] Among them, the opening of the boom selection valve is controlled according to the current action type of the excavator and the working pressure of the hydraulic system, including: when the working pressure of the hydraulic system is lower than the set first limit value, the opening limit value of the boom selection valve is determined according to the swing pilot pressure value, so that the opening of the boom selection valve is less than the opening limit value of the boom selection valve; when the boom and swing are in action at the same time, the initial value a of the boom selection valve opening coefficient and the swing action coefficient s are determined according to the boom retraction handle pilot signal, and the boom selection valve opening limit value coefficient b is determined according to the swing action coefficient s, and the boom selection valve opening limit value coefficient a is compared with the boom selection valve opening limit value coefficient b to obtain the opening coefficient c of the boom selection valve, specifically: if a≤b, then c=a, otherwise c=b.

[0029] The boom selection valve opening limit value coefficient b is linearly negatively correlated with the rotary pilot signal, that is, when the rotary action coefficient s is in the range of 0% to 100%, the corresponding boom selection valve opening limit value coefficient b is 1 to x, where the value range of x is 0 to 1, specifically: b = s*x-s+1.

[0030] Example 3:

[0031] Based on the method for preventing air from being sucked into the bucket arm when the excavator rotates as described in Example 1 and the system for preventing air from being sucked into the bucket arm when the excavator rotates as described in Example 2, this embodiment provides an excavator, including: a plurality of pilot pressure sensors installed at set positions of the excavator, and the plurality of pilot pressure sensors are electrically connected to the controller respectively; the controller is electrically connected to the main pump solenoid valve and the bucket arm selection valve solenoid valve respectively; the controller is configured to execute the method for preventing air from being sucked into the bucket arm when the excavator rotates as described in Example 1.

[0032] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preventing the bucket arm from sucking air into the bucket arm when the excavator rotates, characterized in that: include: Collect the pilot pressure values ​​of each action of the excavator; Determine the current action type of the excavator based on the collected pilot pressure value; According to the current action type of the excavator and the working pressure of the hydraulic system, the opening of the bucket selector valve is controlled to prevent the bucket arm from sucking air when the excavator rotates; Among them, according to the current action type of the excavator and the working pressure of the hydraulic system, the opening of the bucket selector valve is controlled, including: When the boom and the swing are moving at the same time, the boom selection valve opening coefficient initial value a and the swing action coefficient s are determined according to the boom retraction handle pilot signal, and the boom selection valve opening limit value coefficient b is determined according to the swing action coefficient s. The boom selection valve opening coefficient initial value a and the boom selection valve opening limit value coefficient b are compared to obtain the boom selection valve opening coefficient c, specifically: if a≤b, then c=a, otherwise c=b; The arm selection valve opening limit value coefficient b is linearly negatively correlated with the rotary pilot signal, that is, when the rotary action coefficient s is in the range of 0%~100%, the corresponding arm selection valve opening limit value coefficient b is 1~x, where the value range of x is 0~1, specifically: b=s x-s+1.

2. The method for preventing the bucket arm from sucking air when the excavator rotates according to claim 1, characterized in that: According to the current action type of the excavator and the working pressure of the hydraulic system, the opening of the bucket selector valve is controlled, which also includes: When the working pressure of the hydraulic system is lower than the set first limit value, the opening limit value of the boom selection valve is determined according to the swing pilot pressure value, so that the opening of the boom selection valve is smaller than the opening limit value of the boom selection valve.

3. A system for preventing the bucket arm from sucking air into the bucket arm when the excavator rotates, characterized in that: include: The data acquisition module includes several pilot pressure sensors installed at set positions on the excavator to collect the pilot pressure values ​​of each action of the excavator; An action type judgment module is used to judge the current action type of the excavator based on the collected pilot pressure value; The arm selection valve opening control module is used to control the opening of the arm selection valve according to the current action type of the excavator and the working pressure of the hydraulic system, so as to prevent the arm from sucking air when the excavator rotates; Among them, according to the current action type of the excavator and the working pressure of the hydraulic system, the opening of the bucket selector valve is controlled, including: When the boom and the swing are moving at the same time, the boom selection valve opening coefficient initial value a and the swing action coefficient s are determined according to the boom retraction handle pilot signal, and the boom selection valve opening limit value coefficient b is determined according to the swing action coefficient s. The boom selection valve opening coefficient initial value a and the boom selection valve opening limit value coefficient b are compared to obtain the boom selection valve opening coefficient c, specifically: if a≤b, then c=a, otherwise c=b; The arm selection valve opening limit value coefficient b is linearly negatively correlated with the rotary pilot signal, that is, when the rotary action coefficient s is in the range of 0%~100%, the corresponding arm selection valve opening limit value coefficient b is 1~x, where the value range of x is 0~1, specifically: b=s x-s+1.

4. The system for preventing the arm from sucking in air when the excavator rotates according to claim 3, characterized in that: According to the current action type of the excavator and the working pressure of the hydraulic system, the opening of the bucket selector valve is controlled, which also includes: When the working pressure of the hydraulic system is lower than the set first limit value, the opening limit value of the boom selection valve is determined according to the swing pilot pressure value, so that the opening of the boom selection valve is smaller than the opening limit value of the boom selection valve.

5. An excavator, characterized in that: include: Several pilot pressure sensors are installed at set positions of the excavator, and the several pilot pressure sensors are electrically connected to the controller respectively; the controller is electrically connected to the main pump solenoid valve and the boom selection valve solenoid valve respectively; the controller is configured to execute the method of preventing air from being sucked into the boom when the excavator rotates as described in any one of claims 1-2.

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