Die cavity pressure sensor

Abstract

The utility model relates to the field of mold detection, in particular to a mold cavity pressure sensor, which comprises a sensor shell, a sensor core is arranged in the sensor shell, the sensor core comprises a quartz sensing unit, the quartz sensing unit comprises at least three quartz plates, two adjacent quartz plates are arranged at equal intervals, and the quartz plates are arranged in the sensor shell. The quartz plate is mounted along the axis direction of the sensor shell, one end of the sensor shell is provided with a sensing surface, and the sensing surface is provided with a high-hardness structural layer, so that the working area of the sensing unit can be increased, and meanwhile, the thickness of the sensing unit is increased, thereby ensuring that the transverse shearing force resistance of the sensing unit is strong; therefore, the response frequency of the sensor can be effectively improved, the sensor can more quickly reflect the change of the internal pressure of the mold cavity, the requirement of the high-speed forming process on the response speed of the sensor is met, the monitoring effect is better in the mold production process, the monitoring error is small, and the yield of the mold is improved.

Description

Technical Field

[0001] The utility model relates to the field of mold detection, in particular to a mold cavity pressure sensor. Background Art

[0002] In the production process of injection molding and die-casting molds, the plastic or metal material is heated to a certain temperature to soften the material and have a certain fluidity. It is then injected into the mold under high pressure and cooled and solidified to form a product. There are often pressure sensors in injection molding machines and metal pressure devices, but after passing through the nozzle and flow channel, the pressure loss inside the mold is very large. Therefore, the above-mentioned sensors cannot reflect the pressure inside the mold cavity and cannot monitor the product forming process. If accurate detection of the mold cavity is to be achieved, the traditional monitoring environment cannot meet the requirements due to the short injection time of plastic and metal in the mold cavity. The response frequency of the traditional sensor cannot meet the requirements, and due to the high temperature in the mold cavity, the heat resistance of the traditional sensor is poor, resulting in large temperature drift, large flow damping of plastic and metal in the mold cavity, and poor resistance to lateral shear force of the traditional sensor. As a result, the traditional sensor cannot adapt to the mold cavity environment during mold cavity monitoring, resulting in large errors and inaccuracies in the monitoring results, which leads to low mold yield and high production costs. Utility Model Content

[0003] The purpose of the utility model is to provide a mold cavity pressure sensor to address the problem that traditional pressure sensors in the background technology cannot adapt to the mold cavity environment when performing mold cavity monitoring, resulting in large errors and inaccuracies in monitoring results, thereby leading to low mold yield and high production costs.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0005] A mold cavity pressure sensor, the sensor comprises a sensor housing, a sensor core is arranged in the sensor housing, the sensor core comprises a quartz sensitive unit, the quartz sensitive unit comprises at least three quartz plates, two adjacent quartz plates are arranged at equal intervals, the quartz plates are installed along the axial direction of the sensor housing, and a sensing surface is arranged at one end of the sensor housing.

[0006] The utility model is a cavity pressure sensor, in which a quartz sensitive unit is arranged to convert a force signal transmitted from a sensing surface into a charge signal. Since the sensitive unit is made of quartz material, this material has excellent high temperature performance and corrosion resistance, and can stably work in high temperature environments such as injection molding and die casting, thereby avoiding monitoring errors caused by temperature drift of traditional sensors. The quartz sensitive unit contains at least three quartz sheets, and adjacent quartz sheets are arranged at equal intervals, so that the working area of ​​the sensitive unit can be increased, and the thickness of the sensitive unit is increased, thereby ensuring that the sensitive unit has strong resistance to lateral shear force, thereby effectively improving the response frequency of the sensor, enabling it to more quickly respond to changes in the pressure inside the cavity, and meeting the requirements of the high-speed molding process for the sensor response speed, so that the monitoring effect is better and the monitoring error is small during the production process of the mold, thereby improving the yield rate of the mold.

[0007] As a preferred solution of the utility model, the sensor housing includes a sensor head end, the sensing surface is arranged at the sensor head end, a sensor waist is provided at the end of the sensor head end away from the sensing surface, the sensor core is located in the sensor waist, a first arc-shaped transition section is provided at the connection between the sensor waist and the sensor head end, the sensor waist is an elastic structural part, and a first insulating layer is provided between the sensor waist and the sensor core. This arrangement avoids stress concentration in the sensor housing and improves its service life. At the same time, the first insulating layer prevents leakage of charge signals and improves the accuracy of monitoring.

[0008] As a preferred solution of the utility model, the sensing surface body is made of a high-hardness material, such as alloy, diamond, etc., to improve the wear resistance and corrosion resistance of the sensing surface.

[0009] As a preferred solution of the utility model, an annular installation groove is provided on the head end of the sensor, and a sealing ring is provided in the annular installation groove. Such an arrangement can ensure that the sensing surface is always in the center of the mold cavity, thereby improving the measurement accuracy.

[0010] As a preferred solution of the utility model, an installation and fixing part is provided at one end of the sensor waist away from the sensor head end, a signal transmission part is provided in the installation and fixing part, a second arc-shaped transition section is provided at the connection between the installation and fixing part and the sensor waist, and a second insulating layer is provided between the installation and fixing part and the signal transmission part. This arrangement avoids stress concentration on the sensor housing and improves the service life of the sensor. At the same time, the second insulating layer can further prevent leakage of charge signals.

[0011] As a preferred solution of the utility model, the sensor head end, the sensor waist and the mounting and fixing part are integral structural parts, and such an arrangement increases the structural stability of the sensor.

[0012] As a preferred solution of the utility model, the mounting fixing part includes a fixing part, the fixing part is connected with the waist of the sensor, a threaded connection part is provided at one end of the fixing part away from the waist of the sensor, and a clamping position is provided between the threaded connection part and the fixing part, so that the sensor and the connector can be stably connected.

[0013] As a preferred solution of the utility model, a first conductive pad is provided at one end of the quartz sensitive unit close to the sensing surface, and a second conductive pad is provided at one end of the quartz sensitive unit away from the sensing surface, so as to transmit and receive charge signals.

[0014] As a preferred solution of the utility model, an insulating ceramic part is provided at one end of the second conductive pad away from the quartz sensitive unit, and the signal transmission part is inserted in the middle of the insulating ceramic part. This arrangement can prevent charge signal leakage while ensuring stable signal transmission.

[0015] As a preferred solution of the utility model, the signal transmission part includes a signal transmission terminal connected to the insulating ceramic part, and the signal transmission terminal passes through the insulating ceramic part and is connected to the second conductive pad. This arrangement can ensure stable transmission of the charge signal.

[0016] As a preferred solution of the utility model, the end of the signal transmission terminal away from the second conductive pad is connected to a conductive spring, and the end of the conductive spring away from the signal transmission terminal is provided with a contact, so that the charge signal can be transmitted to the connecting line.

[0017] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0018] 1. The utility model is a cavity pressure sensor, in which a quartz sensitive unit is arranged to convert the force signal transmitted from the sensing surface into a charge signal. Since the sensitive unit is made of quartz material, this material has excellent high temperature performance and corrosion resistance, and can work stably in high temperature environments such as injection molding and die casting, avoiding the monitoring error caused by temperature drift of traditional sensors. In addition, the quartz sensitive unit contains at least three quartz plates, and adjacent quartz plates are arranged at equal intervals, so that the working area of ​​the sensitive unit can be increased, and the thickness of the sensitive unit is increased, thereby ensuring that the sensitive unit has strong resistance to lateral shear force, thereby effectively improving the response frequency of the sensor, enabling it to more quickly respond to changes in the pressure inside the cavity, meeting the requirements of the high-speed molding process for the sensor response speed, so that the monitoring effect is better in the production process of the mold, the monitoring error is small, and the yield of the mold is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a cross-sectional schematic diagram of the mold cavity sensor of the utility model;

[0020] Figure 2 This utility model Figure 1 A magnified view of part A;

[0021] Figure 3 This utility model Figure 1 A magnified view of part B;

[0022] Figure 4 This utility model Figure 1 Enlarged view of part C;

[0023] Figure 5 It is a schematic diagram of the mold cavity sensor structure of Example 2 of the present utility model.

[0024] Icons: 1-sensor housing; 11-sensing surface; 12-sensor head; 121-annular mounting groove; 122-sealing ring; 13-sensor waist; 131-first insulating layer; 14 first arc-shaped transition section; 15-installation fixing part; 151-second insulating layer; 152-fixing part; 153-threaded connection part; 154-locking position; 16-second arc-shaped transition section; 3-quartz sensitive unit; 31-quartz plate; 4-signal transmission part; 41-signal transmission terminal; 42-conductive spring; 43-contact; 5-first conductive pad; 6-second conductive pad; 7-insulating ceramic part. DETAILED DESCRIPTION

[0025] The utility model is described in detail below in conjunction with the accompanying drawings.

[0026] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0027] Example 1

[0028] A mold cavity pressure sensor, the sensor includes a sensor housing 1 for contacting the mold cavity, the sensor housing 1 body is made of high-hardness material, and a sensor core is arranged in the sensor housing 1, through which signal transmission can be achieved, the sensor core includes a quartz sensitive unit 3, and the quartz sensitive unit 3 is composed of at least three quartz plates 31, and the quartz plates 31 in the quartz sensitive unit 3 are arranged at equal intervals and installed along the axial direction of the sensor housing 1, so that when the sensor is in use, the sensor core has a strong ability to resist the lateral shear force caused by the flow of plastic or metal in the mold cavity, thereby ensuring the response speed of the sensor core, and at the same time, because the material of the sensitive unit is quartz material, quartz has the characteristic of high temperature resistance, so that the temperature drift of the sensor is small when in use, and there is no creep and hysteresis effect.

[0029] As mentioned above, the quartz sensitive unit 3 is provided with a first conductive pad 5 at one end close to the sensing surface 11, and the quartz sensitive unit 3 is provided with a second conductive pad 6 at one end away from the sensing surface 11. This arrangement is used to transmit and receive charge signals. The second conductive pad 6 is provided with an insulating ceramic part 7 at one end away from the quartz sensitive unit 3, and the signal transmission part 4 is inserted in the middle of the insulating ceramic part 7. This arrangement can prevent the leakage of charge signals while ensuring stable transmission of signals.

[0030] As mentioned above, the sensor housing 1 includes a sensor head 12 provided with a sensing surface 11, which senses the pressure in the mold cavity through the sensing surface 11, and transmits its pressure signal to the sensor core to be converted into a charge signal, and the sensing surface 11 body is a high-hardness structure, which improves the wear resistance and service life of the sensor;

[0031] Furthermore, a sensor waist 13 is provided at one end of the sensor head 12 away from the sensing surface 11, and the main body of the sensor waist 13 is an elastic structural part, so that after the sensor is loaded with prestressed assembly, the elastic structure can ensure stable prestress, thereby ensuring the sensitivity and linearity of the sensor, and further ensuring the accuracy of the sensor, and a first arc-shaped transition section 14 is provided at the junction of the sensor waist 13 and the sensor head 12. The circular arc transition of the first arc-shaped transition section 14 can effectively avoid stress concentration, evenly disperse stress, and prevent irreversible deformation.

[0032] As mentioned above, an annular mounting groove 121 is provided on the sensor head end 12, and a sealing ring 122 is provided in the annular mounting groove 121. By setting the sealing ring 122, the sensor head end 12 is placed in the mold cavity, and the mold cavity is sealed to ensure that the sensing surface 11 is always kept in the center and is not disturbed by lateral forces or friction forces. It is ensured that under various conditions, the mold cavity pressure is vertically transmitted to the sensing surface 11, thereby ensuring measurement accuracy.

[0033] As mentioned above, one end of the sensor waist 13 is connected to a mounting and fixing portion 15215, and a second arc-shaped transition section 16 is provided at the junction of the mounting and fixing portion 15215 and the sensor waist 13. The second arc-shaped transition section 16 can avoid stress concentration in the sensor housing 1, which leads to a reduction in life. A signal transmission portion 4 is provided in the mounting and fixing end, and a second insulating layer 151 is provided between the mounting and fixing end and the signal transmission portion 4. The second insulating layer 151 can ensure that the charge signal transmitted from the sensor core will not leak;

[0034] Furthermore, the signal transmission part 4 includes a signal transmission terminal 41 connected to the insulating ceramic part 7, and the signal transmission terminal 41 passes through the insulating ceramic part 7 and is connected to the second conductive pad 6. Such an arrangement can ensure stable transmission of the charge signal. The end of the signal transmission terminal 41 away from the second conductive pad 6 is connected to a conductive spring 42, and the end of the conductive spring 42 away from the signal transmission terminal 41 is provided with a contact 43. Such an arrangement can transmit the charge signal to the connecting line.

[0035] As mentioned above, the sensor head end 12, the sensor waist 13 and the mounting and fixing part 15 are integral structural parts, which ensure the structural stability of the sensor.

[0036] As mentioned above, the installation fixing part 15 includes a fixing part 152 connected to the sensor waist 13, and a threaded connection part 153 is provided at one end of the fixing part 152 away from the sensor waist 13, and a clamping position 154 is provided between the threaded connection part 153 and the inside of the valley bottom. The clamping position 154 can improve the sealing performance of the connector and achieve a waterproof and anti-fouling effect.

[0037] Example 2

[0038] This embodiment 2 applies the cavity sensor in embodiment 1 to precision instruments, such as the internal structure of a mobile phone camera, a medical injection device, a precision bionic device, etc. Since the product itself has a tiny structure and the surface area that can be monitored does not exceed 1 mm, this embodiment 2 makes a certain degree of structural modification to embodiment 1, and the modification process is as follows:

[0039] The size of the sensing surface 11 of the cavity sensor is modified to a form with a diameter less than 1mm, and the sensor head end 12 is set to a thin film flexible structure, and the thickness of the thin film flexible structure is less than 0.1mm, and it is uniform, and the annular error is less than 0.002mm, to ensure that there is no unbalanced load, so that the forces in all directions are uniformly and consistently transmitted to the sensitive unit. Through the high elasticity and high displacement of the thin film flexible structure, the cavity pressure is almost completely transmitted to the sensitive unit, ensuring that other structures do not share the force, and the thin film flexible structure is elastic. During the use of the sensor, the preload force remains unchanged, so the sensor sensitivity and consistency can also be stable for a long time, which greatly enhances the detection accuracy of the sensor in long-term use.

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A cavity pressure sensor, characterized in that: The sensor comprises a sensor housing (1), wherein a sensor core is arranged in the sensor housing (1), wherein the sensor core comprises a quartz sensitive unit (3), wherein the quartz sensitive unit (3) comprises at least three quartz plates (31), wherein two adjacent quartz plates (31) are arranged at equal intervals, wherein the quartz plates (31) are installed along the axial direction of the sensor housing (1), and a sensing surface (11) is arranged at one end of the sensor housing (1).

2. A cavity pressure sensor according to claim 1, characterized in that: The sensor housing (1) comprises a sensor head end (12), the sensing surface (11) is arranged at the sensor head end (12), a sensor waist (13) is arranged at one end of the sensor head end (12) away from the sensing surface (11), the sensor core is located in the sensor waist (13), a first arc-shaped transition section (14) is arranged at the junction of the sensor waist (13) and the sensor head end (12), the sensor waist (13) is an elastic structural part, and a first insulating layer (131) is arranged between the sensor waist (13) and the sensor core.

3. A cavity pressure sensor according to claim 2, characterized in that: An annular installation groove (121) is provided on the sensor head end (12), and a sealing ring (122) is provided in the annular installation groove (121).

4. A cavity pressure sensor according to claim 3, characterized in that: An installation and fixing portion (15) is provided at one end of the sensor waist (13) away from the sensor head end (12), a signal transmission portion (4) is provided in the installation and fixing portion (15), a second arc-shaped transition section (16) is provided at the junction between the installation and fixing portion (15) and the sensor waist (13), and a second insulating layer (151) is provided between the installation and fixing portion (15) and the signal transmission portion (4).

5. A cavity pressure sensor according to claim 4, characterized in that: The sensor head end (12), the sensor waist (13) and the mounting and fixing portion (15) are integral structural components.

6. A cavity pressure sensor according to any one of claims 4 to 5, characterized in that: The mounting fixing portion (15) comprises a fixing portion (152), the fixing portion (152) being connected to the sensor waist portion (13), a threaded connection portion (153) being provided at one end of the fixing portion (152) away from the sensor waist portion (13), and a locking position (154) being provided between the threaded connection portion (153) and the fixing portion (152).

7. A cavity pressure sensor according to claim 6, characterized in that: A first conductive pad (5) is provided at one end of the quartz sensitive unit (3) close to the sensing surface (11), and a second conductive pad (6) is provided at one end of the quartz sensitive unit (3) away from the sensing surface (11).

8. A cavity pressure sensor according to claim 7, characterized in that: An insulating ceramic portion (7) is provided at one end of the second conductive pad (6) away from the quartz sensitive unit (3), and the signal transmission portion (4) is inserted into the middle of the insulating ceramic portion (7).

9. A cavity pressure sensor according to claim 8, characterized in that: The signal transmission part (4) comprises a signal transmission terminal (41) connected to the insulating ceramic part (7), and the signal transmission terminal (41) passes through the insulating ceramic part (7) and is connected to the second conductive pad (6).

10. A cavity pressure sensor according to claim 9, characterized in that: One end of the signal transmission terminal (41) away from the second conductive pad (6) is connected to a conductive spring (42), and one end of the conductive spring (42) away from the signal transmission terminal (41) is provided with a contact point (43).

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