阅读说明：本技术 容积测量装置及其使用方法 (Volume measuring device and method of use thereof ) 是由 安瑞桢 于 2020-06-30 设计创作，主要内容包括：本发明提出一种容积测量装置,涉及工业自动化设备领域,包括测量装置本体和温控装置；测量装置本体包括可压缩的气室、用于测量该气室的容积变化的容积变化测量装置、与该气室连通的压强传感器和与该气室连通的连接部；连接部用于与待测部件连通；温控装置用于控制气室、压强传感器、连接部和待测部件内部的气体的温度保持恒定。还公开了该装置的使用方法。本发明能实现高精度容积测量,可在线自我标定系统容积V<Sub>0</Sub>；使用现场环境的大气作为介质进行测量；自动化生产的铸件型腔容积为稳定值,通过将测量值与理论容积或合格件的型腔容积进行比较,即可知晓型腔内是否有多余的砂块或未知物；可实现检测的自动化、效率高、精度高,降低大量人力成本。(The invention provides a volume measuring device, which relates to the field of industrial automation equipment and comprises a measuring device body and a temperature control device; the measuring device body comprises a compressible air chamber, a volume change measuring device for measuring the volume change of the air chamber, a pressure sensor communicated with the air chamber and a connecting part communicated with the air chamber; the connecting part is used for communicating with a component to be tested; the temperature control device is used for controlling the temperature of the gas in the gas chamber, the pressure sensor, the connecting part and the part to be measured to be constant. Methods of use of the device are also disclosed. The invention can realize high-precision volume measurement and can self-calibrate the system volume V on line 0 (ii) a Measuring using the atmosphere of the field environment as a medium; the volume of a casting cavity produced automatically is a stable value, and whether redundant sand blocks or unknown objects exist in the cavity can be known by comparing a measured value with a theoretical volume or the volume of the cavity of a qualified part; the automatic detection device has the advantages of being capable of achieving automation, high in efficiency and high in precision of detection and reducing a large amount of labor cost.)

1. A volume measuring device is characterized by comprising a measuring device body and a temperature control device;

the measuring device body comprises a compressible air chamber, a volume change measuring device for measuring the volume change of the air chamber, a pressure sensor communicated with the air chamber and a connecting part communicated with the air chamber; the connecting part is used for being communicated with a component to be tested;

the temperature control device is used for controlling the temperature of the gas in the gas chamber, the pressure sensor, the connecting part and the part to be measured to be constant.

2. The volume measuring device of claim 1, wherein the air chamber comprises an air chamber, a piston is arranged in the air chamber and can slide along the inner wall of the air chamber, and the piston is connected with a piston rod;

the volume change measuring device is a displacement measuring device which is used for measuring the displacement L of the piston; when the sectional area of the piston is S, the volume change amount of the gas chamber is Δ V ≡ S × L.

3. A volume measuring device according to claim 2, wherein the displacement measuring device is a grating ruler; the pressure sensor is an absolute pressure sensor.

4. The method of using the volume measuring device of claim 1, comprising the steps of:

the method comprises the following steps of (I), communicating a connecting part with a component to be tested;

(II) placing the air chamber in an initial volume state, and recording the total volume of the air chamber, the pressure sensor and the connecting part as V at the moment₀Volume in the part to be measured is denoted as V_a；

Thirdly, the temperature control device works to keep the temperature of the gas in the gas chamber, the pressure sensor, the connecting part and the part to be measured constant;

compressing the air chamber to obtain a first steady state parameter, and measuring a first steady state pressure P by the pressure sensor₁The volume change measuring device obtains a first steady volume change amount DeltaV₁(ii) a Continuously compressing the air chamber to obtain a second steady state parameter, and measuring a second steady state pressure P by the pressure sensor₂The volume change measuring device obtains a second steady volume change amount DeltaV₂；

(IV) formula

5. Use of a volume measuring device according to claim 4, wherein V is₀Calibration may be performed by:

sealing the end part of the connecting part, which is connected with the component to be tested;

(II) placing the air chamber in an initial volume state, and recording the total volume of the air chamber, the pressure sensor and the connecting part as V at the moment₀；

Thirdly, the temperature control device works to keep the temperature of the gas in the gas chamber, the pressure sensor and the connecting part constant;

compressing the air chamber to obtain a third steady state parameter, and measuring a third steady state pressure P by the pressure sensor₃The volume change measuring device obtains a third steady-state volume change amount DeltaV₃(ii) a Continuously compressing the air chamber to obtain a fourth steady state parameter, and measuring a fourth steady state pressure P by the pressure sensor₄The volume change measuring device obtains a fourth steady volume change amount DeltaV₄；

(IV) formulaCalculate V₀Can realize the V-pair₀Initial calibration of (1).

Technical Field

The invention relates to the field of industrial automation equipment, in particular to a volume measuring device and a using method thereof.

Background

An oil duct is designed in the casting parts of the engine cylinder body and the cylinder cover, and after the casting parts are subjected to sand removing treatment, whether residual sand blocks are left in a cavity or not needs to be checked. The usual approach is: 1. roughly detecting, irradiating a certain cavity hole by using a strong light flashlight, and manually observing whether the rest same-type cavity holes are irradiated by light to an observed cavity so as to determine whether a large sand block blocks a channel between the cavities (positions which cannot be reached by visual inspection cannot be inspected); 2. the precision inspection is carried out, the endoscope is used for carrying out inspection one by one, the efficiency is very low, and the possibility of missed inspection caused by human errors exists. A plurality of rough detection and fine detection stations are usually arranged on an automatic casting line and are all manually detected, and the problems of missing detection and false detection caused by errors of manual detection exist. Meanwhile, in order to meet the production rhythm, a plurality of manual stations are required to be arranged on the same production line, and the cost is greatly increased. Therefore, there is an urgent need for a device or equipment capable of automatically checking whether sand remains in the oil passage, so as to realize reliable and efficient automatic checking.

Disclosure of Invention

The invention provides a volume measuring device, which solves the problems of poor inspection effect, low efficiency and high cost of a casting oil passage inspection means in the prior art.

The technical scheme of the invention is realized as follows:

a volume measuring device comprises a measuring device body and a temperature control device;

the measuring device body comprises a compressible air chamber, a volume change measuring device for measuring the volume change of the air chamber, a pressure sensor communicated with the air chamber and a connecting part communicated with the air chamber; the connecting part is used for being communicated with a component to be tested;

the temperature control device is used for controlling the temperature of the gas in the gas chamber, the pressure sensor, the connecting part and the part to be measured to be constant.

Further, the air chamber comprises an air chamber, a piston capable of sliding along the inner wall of the air chamber is arranged in the air chamber, and the piston is connected with a piston rod;

the volume change measuring device is a displacement measuring device which is used for measuring the displacement L of the piston; when the sectional area of the piston is S, the volume change amount of the gas chamber is Δ V ≡ S × L.

Furthermore, the displacement measuring device is a grating ruler; the pressure sensor is an absolute pressure sensor.

The use method of the volume measuring device comprises the following steps:

the method comprises the following steps of (I), communicating a connecting part with a component to be tested;

(II) placing the air chamber in an initial volume state, and recording the total volume of the air chamber, the pressure sensor and the connecting part as V at the moment₀Volume in the part to be measured is denoted as V_a；

Thirdly, the temperature control device works to keep the temperature of the gas in the gas chamber, the pressure sensor, the connecting part and the part to be measured constant;

compressing the air chamber to obtain a first steady state parameter, and measuring a first steady state pressure P by the pressure sensor₁The volume change measuring device obtains a first steady volume change amount DeltaV₁(ii) a Continuously compressing the air chamber to obtain a second steady state parameter, and measuring a second steady state pressure P by the pressure sensor₂The volume change measuring device obtains a second steady volume change amount DeltaV₂；

(IV) formula

Calculating the volume V in the component to be measured_a。

Further, the V₀Calibration may be performed by:

sealing the end part of the connecting part, which is connected with the component to be tested;

(II) placing the air chamber in an initial volume state, and recording the total volume of the air chamber, the pressure sensor and the connecting part as V at the moment₀；

Thirdly, the temperature control device works to keep the temperature of the gas in the gas chamber, the pressure sensor and the connecting part constant;

compressing the air chamber to obtain a third steady state parameter, and measuring a third steady state pressure P by the pressure sensor₃The volume change measuring device obtains a third steady-state volume change amount DeltaV₃(ii) a Continuously compressing the air chamber to obtain a fourth steady state parameter, and measuring a fourth steady state pressure P by the pressure sensor₄The volume change measuring device obtains a fourth steady volume change amount DeltaV₄；

(IV) formulaCalculate V₀Can realize the V-pair₀Initial calibration of (1).

The invention has the beneficial effects that:

the invention has simple structure and convenient use; the invention can realize high precisionVolume measurement, on-line self-calibration of system volume V₀(ii) a Measuring using the atmosphere of the field environment as a medium; the volume of a casting cavity produced automatically is a stable value, and whether redundant sand blocks or unknown objects exist in the cavity can be known by comparing a measured value with a theoretical volume or the volume of the cavity of a qualified part; the automatic detection device has the advantages of being capable of achieving automation, high in efficiency and high in precision of detection and reducing a large amount of labor cost.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of the present invention in a configuration for measurement in connection with a part to be measured;

FIG. 2 shows the calibration V of the present invention₀Schematic structural diagram of the time.

Wherein:

1. an air chamber; 2. a pressure sensor; 3. a connecting portion; 4. an air cavity; 5. a piston; 6. a piston rod; 7. a component under test.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1-2, the volume measuring device of the present embodiment includes a measuring device body and a temperature control device (not shown).

The measuring device body comprises a compressible air chamber 1, a volume change measuring device (not shown in the figure) for measuring the volume change of the air chamber 1, a pressure sensor 2 communicated with the air chamber 1 and a connecting part 3 communicated with the air chamber 1; the connecting portion 3 is used for communicating with a component 7 to be measured. The tightness of the compressible gas chamber 1 can be checked by the pressure loss at steady state of the system.

The temperature control device is used for controlling the temperature of the gas in the gas chamber 1, the pressure sensor 2, the connecting part 3 and the component to be measured 7 to be kept constant.

In this embodiment, the air chamber 1 includes an air chamber 4, a piston 5 capable of sliding along the inner wall of the air chamber 4 is disposed in the air chamber 4, and the piston 5 is connected with a piston rod 6. Here, the air chamber 4 is cylindrical and the piston 5 is disc-shaped. The piston 5 can be pulled to slide in the air cavity 4 through the piston rod 6, so that the compression of the air cavity 1 is realized, and the change of the volume is realized.

The volume change measuring device is a displacement measuring device which is used for measuring the displacement L of the piston 5; the cross-sectional area of the piston 5, S, is measurable and the cross-sectional area of the piston 5 is equal to the cross-sectional area of the air chamber 4. The volume change amount Δ V ≡ sxl of the gas chamber 1.

In this embodiment, the displacement measuring device is a grating ruler, which can measure the displacement L of the piston 5. The pressure sensor 2 is an absolute pressure sensor 2, and a differential pressure sensor can be selected in practical application. The pressure sensor 2 may measure the pressure value inside the gas chamber 1.

The use method of the volume measuring device comprises the following steps:

referring to fig. 1, the connection portion 3 is communicated with the member to be measured 7.

(II) placing the air chamber 1 in an initial volume state, and recording the total volume of the air chamber 1, the pressure sensor 2 and the connecting part 3 as V₀The volume inside the part to be measured 7 is denoted as V_a。

And (III) the temperature control device works to keep the temperature of the gas in the gas chamber 1, the pressure sensor 2, the connecting part 3 and the component to be measured 7 constant.

Compressing the air chamber 1, namely pushing the piston rod 6 to enable the piston 5 to slide and stop when the piston 5 reaches a certain position, obtaining a first steady state parameter, and measuring a first steady state pressure P by the pressure sensor 2₁The volume change measuring device obtains a first steady volume change amount DeltaV₁。ΔV₁The obtaining may be calculated with reference to Δ V ≡ S × L as described above, i.e. the displacement measuring means obtains the first steady-state displacement L₁Then Δ V₁≡S×L₁. Δ V herein₁The amount of change in the volume of the gas chamber 1 is measured, and Δ V is the same since the volumes in the pressure sensor 2 and the connection part 3 are not changed₁It is also possible to indicate the amount of change in the total volume within the gas chamber 1, the pressure sensor 2 and the connection portion 3.

Similarly, the air chamber 1 is continuously compressed to obtain a second steady state parameter, and the pressure sensor 2 measures a second steady state pressure P₂The volume change measuring device obtains a second steady volume change amount DeltaV₂；

(IV) formulaCalculating the volume V in the part 7_a。

About V_aThe reason for the calculation formula (c) is that: according to the ideal gas state equation P ═ ρ RT,

in the formula: p-absolute pressure, rho-density, R-fluid constant, T-temperature;

namely, it isWhere m is the total mass of gas enclosed in the system, the value is constant during compression, the temperature T is kept constant by the temperature control device, and R is a constant.

Then at the first steady state, RT (m)₀+m_a)＝P₁(V₀+V_a-ΔV₁)；

At the second steady state, RT (m)₀+m_a)＝P₂(V₀+V_a-ΔV₂)；

Can be obtained, P₁(V₀+V_a-ΔV₁)＝P₂(V₀+V_a-ΔV₂)，

The derivation can be obtained by the following steps,

measured V_aComparing the value with the theoretical volume or the volume of the cavity of a qualified part to know whether redundant sand blocks or unknown objects exist in the cavity; the automatic detection device has the advantages of being capable of achieving automation, high in efficiency and high in precision of detection and reducing a large amount of labor cost. In this embodiment, the measurement is performed using the atmosphere in the field environment as a medium, and in actual use, any known ideal gas may be selected as the medium for the measurement. V of qualified product can also be obtained by the above measuring method_aValues are used as theoretical volumes as basis for alignment of other measurements.

V₀The constant value is a known value, and in this embodiment, the value may also be calibrated in advance, and the calibration may be performed through the following steps:

referring to fig. 2, the connection portion 3 is used to seal the end portion connected to the member to be measured 7.

(II) placing the air chamber 1 in an initial volume state, and recording the total volume of the air chamber 1, the pressure sensor 2 and the connecting part 3 as V₀。

And (III) the temperature control device works to keep the temperature of the gas in the gas chamber 1, the pressure sensor 2 and the connecting part 3 constant.

Compressing the air chamber 1 to obtain a third steady state parameter, and measuring a third steady state pressure P by the pressure sensor 2₃The volume change measuring device obtains a third steady-state volume change amount DeltaV₃(ii) a Continuously compressing the air chamber 1 to obtain a fourth steady state parameter, and measuring a fourth steady state pressure P by the pressure sensor 2₄The volume change measuring device obtains a fourth steady volume change amount DeltaV₄。

(IV) formula

Calculate V₀Can realize the V-pair₀Initial calibration of (1).

About V₀The above-mentioned origin of the calculation formula (2) with respect to V can be referred to_aIs calculated byAnd (4) derivation of the formula. According to an ideal gas state equation, the following can be obtained:

in the third steady state, RTm₀＝P₃(V₀-ΔV₃)；

In the fourth steady state, RTm₀＝P₄(V₀-ΔV₄)；

Can be obtained, P₃(V₀-ΔV₃)＝P₄(V₀-ΔV₄)，

The derivation can be obtained by the following steps,

the volume V of the system can be calibrated on line by the embodiment₀。

In the present embodiment, each Δ V is obtained by calculating the cross-sectional area of the piston 5 and the displacement amount of the piston 5. Each P value is measured by a pressure sensor 2. The temperature control device ensures that the temperature of the gas in the system is unchanged in the compression process. The values of Δ V and P are measured at steady state of the system.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.