High-precision pressure sensor

Abstract

The invention provides a high-precision pressure sensor. The high-precision pressure sensor comprises a shell, a stress pressure head movably installed on the shell, an elastic assembly installed in the shell and a sensing assembly. The stress pressure head comprises a pressing part, a movable part and a boss part; the pressing part extends out of the shell, and the movable part is accommodated in the shell; the boss part is used for abutting against the elastic assembly. The sensing assembly comprises a distance sensor and a sensing sheet; the distance sensor is installed in the shell, the induction piece is installed on the lower surface of the boss part, and the induction piece is located over the distance sensor. The elastic assembly comprises a first elastic piece and a second elastic piece, the movable part is sleeved with the first elastic piece and the second elastic piece, the first elastic piece abuts against the boss part, and the second elastic piece abuts against the first elastic piece. According to the high-precision pressure sensor, the pressure value can be accurately measured through the deformation quantity of the first elastic piece and the second elastic piece according to the pressure, and the pressure testing precision is high.

Description

Technical Field

[0001] The present invention relates to the technical field of sensor equipment, and in particular to a pressure sensor. Background Art

[0002] The principle used by traditional pressure sensors is the piezoelectric effect. The force-bearing component is a piezoresistor. When subjected to pressure, the piezoresistor changes, causing the resistance value of the piezoresistor to change. The pressure sensor outputs an electrical signal, and the pressure is calculated based on the electrical signal.

[0003] However, the resistance of the varistor of a traditional pressure sensor will not only change due to the deformation of the varistor, but will also be affected by environmental conditions (such as temperature, humidity, etc.), and temperature has a greater impact on the resistance of the varistor, resulting in low accuracy of the pressure sensor. Summary of the invention

[0004] The present invention provides a high-precision pressure sensor which can accurately measure the pressure value according to the size of the pressure through the deformation amount of the spring piece, thereby effectively improving the pressure test accuracy.

[0005] The technical solution adopted by the present invention is: a high-precision pressure sensor, which comprises: a housing, a pressure head movably mounted on the housing, an elastic component and a sensing component mounted in the housing;

[0006] The pressure head includes a pressing part, a movable part connected to the pressing part, and a boss part connected between the pressing part and the movable part; the pressing part extends out of the shell, and the movable part is accommodated in the shell; the boss part is used to press the elastic component;

[0007] The sensing component includes a distance sensor and a sensing sheet; the distance sensor is installed in the housing, the sensing sheet is installed on the lower surface of the boss portion, and the sensing sheet is located directly above the distance sensor;

[0008] The elastic component comprises a first elastic sheet and a second elastic sheet. The first elastic sheet and the second elastic sheet are both sleeved on the movable portion. The first elastic sheet abuts against the boss portion, and the second elastic sheet abuts against the first elastic sheet.

[0009] Furthermore, a through hole is provided in the middle of the first spring piece for the movable part to pass through, and a plurality of slots are provided radially from the through hole toward the outer circumference, and the plurality of slots divide the first spring piece into a plurality of slot pieces.

[0010] Furthermore, the structure and shape of the second elastic piece are the same as those of the first elastic piece.

[0011] Furthermore, the thickness of the first elastic sheet is smaller than the thickness of the second elastic sheet.

[0012] Furthermore, the thickness of the first spring sheet is 1.7 mm, and the thickness of the second spring sheet is 3.8 mm.

[0013] Furthermore, a first spacer ring is sandwiched between the first spring sheet and the lower shell, a second spacer ring is sandwiched between the first spring sheet and the second spring sheet, and a third spacer ring is sandwiched between the second spring sheet and the upper shell.

[0014] Furthermore, the housing comprises an upper shell and a lower shell, the pressing portion extends downward out of the lower shell, and the movable portion is accommodated in the upper shell.

[0015] Furthermore, a fixing portion is provided in the lower shell, and a locking hole is provided in the boss portion, and a locking rod is used in the locking hole to lock the force-bearing pressure head and the fixing portion; and the aperture of the locking hole is larger than the diameter of the locking rod.

[0016] Furthermore, the distance sensor is connected with a connecting wire, and the connecting wire extends out of the upper shell and the lower shell.

[0017] Furthermore, the upper shell is provided with a containing space to accommodate the lifting and lowering movement of the movable part; and a connecting hole is also provided in the middle of the upper shell to connect with other mechanisms.

[0018] Compared with the prior art, the high-precision pressure sensor of the present invention is achieved by setting a sensing sheet on a stressed pressure head, and setting a first spring sheet to abut against the stressed pressure head, and a second spring sheet to abut against the first spring sheet; when the stressed pressure head is subjected to force, the boss portion presses the first spring sheet, causing the first spring sheet to undergo elastic deformation, and the stressed pressure head is displaced, and the distance sensor detects the change in the distance of the sensing sheet installed on the boss portion, which is the deformation amount, and by monitoring the deformation amount, the magnitude of the pressure on the stressed pressure head is calculated; when the deformation amount of the first spring sheet reaches a certain extent, it will contact the second spring sheet, and when the pressing portion is subjected to greater pressure, causing the second spring sheet to deform, the magnitude of the pressure on the stressed pressure head is calculated in the same way; the first spring sheet and the second spring sheet correspond to different force measuring intervals, which effectively improves the detection accuracy of the pressure sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention, but should not constitute a limitation of the present invention.

[0020] Figure 1 : A three-dimensional composite diagram of the high-precision pressure sensor of the present invention;

[0021] Figure 2 : A three-dimensional exploded view of the high-precision pressure sensor of the present invention;

[0022] Figure 3 : A cross-sectional view of the high-precision pressure sensor of the present invention;

[0023] Figure 4 : A three-dimensional diagram of the first spring piece of the high-precision pressure sensor of the present invention. DETAILED DESCRIPTION

[0024] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0025] like Figures 1 to 3 As shown, the high-precision pressure sensor of the present invention includes a housing 1, a pressure head 3 movably mounted on the housing 1; an elastic component mounted in the housing 1 and pressed by the pressure head 3; and a sensing component mounted in the housing 1 and used to sense the displacement of the pressure head 3.

[0026] Specifically, the housing 1 includes an upper shell 101 and a lower shell 102, and the pressure head 3 is movably installed in a space enclosed by the upper shell 101 and the lower shell 102, and the pressure head 3 at least partially extends out of the lower shell 102. The pressure head 3 includes a pressing portion 301, a movable portion 302 connected to the pressing portion 301, and a boss portion 303 connected between the pressing portion 301 and the movable portion 302; wherein the pressing portion 301 extends out of the lower shell 102, and the movable portion 302 is accommodated in the upper shell 101; the boss portion 303 is used to press the elastic component.

[0027] Furthermore, a fixing part 103 is provided in the lower shell 102, and a locking hole 4 is provided in the boss part 303, and a locking rod 5 is used in the locking hole 4 to lock the force-bearing pressing head 3 and the fixing part 103. The hole diameter of the locking hole 4 is larger than the diameter of the locking rod 5, so that there is a gap between the locking hole 4 and the locking rod 5, thereby effectively preventing the force-bearing pressing head 3 from rotating after being stressed, and also playing a guiding role in the lifting and lowering activities of the force-bearing pressing head 3, so that the lifting and lowering of the force-bearing pressing head 3 is not restricted.

[0028] When the pressing portion 301 is subjected to external pressure, the boss portion 303 presses the elastic component, causing the elastic component to deform, and the movable portion 302 moves in the upper housing 101 .

[0029] like Figures 2 to 4 As shown, the sensing component includes a distance sensor 6 and a sensing sheet 7; wherein the distance sensor 6 is installed in the lower housing 102, and the distance sensor 6 is connected to a connecting line 8, and the connecting line 8 extends out of the upper housing 101 and the lower housing 102. The sensing sheet 7 is installed on the lower surface of the boss portion 303, and the sensing sheet 7 is located directly above the distance sensor 6.

[0030] The elastic component includes a first elastic sheet 9 and a second elastic sheet 10 , wherein the first elastic sheet 9 and the second elastic sheet 10 are both sleeved on the movable portion 302 , and the first elastic sheet 9 abuts against the boss portion 303 , and the second elastic sheet 10 abuts against the first elastic sheet 9 .

[0031] The pressure detection principle of the present invention is as follows:

[0032] After the pressing part 301 is subjected to force, the boss part 303 presses the first spring sheet 9, and the first spring sheet 9 is deformed. The boss part 303 drives the sensing sheet 7 to move, so that the distance between the sensing sheet 7 and the distance sensor 6 changes. The distance change measured by the distance sensor 6 is the deformation variable. By monitoring the deformation variable, the pressure on the pressure head 3 can be calculated.

[0033] When the deformation of the first spring piece 9 reaches a certain level, it will contact the second spring piece 10. When the pressing part 301 is subjected to greater pressure, the second spring piece 10 will be deformed. Similarly, the boss part 303 drives the sensing piece 7 to move, causing the distance between the sensing piece 7 and the distance sensor 6 to change. The distance change measured by the distance sensor 6 is the deformation. By monitoring the deformation, the pressure on the pressure head 3 is calculated. In this process, the first spring piece 9 and the second spring piece 10 correspond to different force measurement intervals.

[0034] Specifically, a through hole 11 is provided in the middle of the first spring piece 9 for the movable part 302 to pass through, and a plurality of slots 12 are provided radially from the through hole 11 to the outer circumferential direction. The plurality of slots 12 divide the first spring piece 9 into a plurality of slot pieces 13, so that the first spring piece 9 can produce a greater deformation under the same pressure compared with the traditional pressure sensor; at the same time, the deformation amount of the first spring piece 9 corresponds to the magnitude of the pressure exerted on the pressure head 3.

[0035] The structure and shape of the second spring piece 10 are the same as those of the first spring piece 9 , which will not be described in detail herein. The difference is that the thickness of the first spring piece 9 is smaller than that of the second spring piece 10 .

[0036] In one embodiment, preferably, the thickness of the first spring piece 9 is 1.7 mm, and the thickness of the second spring piece 10 is 3.8 mm; it is understandable that in other embodiments, the thickness of the first spring piece 9 and the second spring piece 10 can be calibrated, measured and set according to each pressure sensor, and is not limited to this.

[0037] Since the accuracy of the sensor is essentially the magnitude of the force applied divided by the deformation of the spring, theoretically, when the forces are equal, the greater the deformation of the spring, the higher the accuracy. Therefore, by radially arranging multiple slots 12 from the middle through hole 11 to the outer circumference of the first spring 9 and the second spring 10, the multiple slots 12 divide the first spring 9 and the second spring 10 into multiple slots 13, so that the first spring 9 and the second spring 10 can produce a greater deformation under the same pressure compared with the traditional pressure sensor, thereby improving the detection accuracy of the pressure sensor.

[0038] Furthermore, a first spacer ring 14 is sandwiched between the first spring sheet 9 and the lower shell 102, a second spacer ring 15 is sandwiched between the first spring sheet 9 and the second spring sheet 10, and a third spacer ring 16 is sandwiched between the second spring sheet 10 and the upper shell 101. The first spacer ring 14, the second spacer ring 15 and the third spacer ring 16 are provided to compress the first spring sheet 9 and the second spring sheet 10.

[0039] In addition, the upper shell 101 is provided with a receiving space 104 to accommodate the lifting and lowering movement of the movable part 302 ; and a connecting hole 17 is also provided in the middle of the upper shell 101 for connecting with other mechanisms.

[0040] The working principle of the high-precision pressure sensor of the present invention is as follows:

[0041] When the pressure head 3 (pressing part 301) is subjected to force, the boss part 303 presses the first spring sheet 9, so that the first spring sheet 9 undergoes elastic deformation, and the pressure head 3 is displaced. The distance sensor 6 detects the distance change of the sensing sheet 7 installed on the boss part 303, which is the deformation amount. By monitoring the deformation amount, the pressure on the pressure head 3 can be calculated.

[0042] When the deformation of the first spring sheet 9 reaches a certain extent, it will contact the second spring sheet 10. When the pressing part 301 is subjected to a greater pressure, the second spring sheet 10 will be deformed. Similarly, the distance change of the safety sensing sheet 7 is detected by the distance sensor 6, which is the deformation. By monitoring the deformation, the pressure on the pressure head 3 is calculated.

[0043] Therefore, the first spring piece 9 and the second spring piece 10 correspond to different force measurement intervals, further improving the detection accuracy of the pressure sensor.

[0044] In summary, the high-precision pressure sensor of the present invention has the following advantages:

[0045] 1. A plurality of slots 12 are radially arranged on the first spring sheet 9 and the second spring sheet 10 from the middle through hole 11 to the outer circumferential direction. The plurality of slots 12 divide the first spring sheet 9 and the second spring sheet 10 into a plurality of slot sheets 13, so that the first spring sheet 9 and the second spring sheet 10 can produce a greater deformation under the same pressure compared with the traditional pressure sensor, thereby improving the detection accuracy of the pressure sensor.

[0046] 2. By setting the second spring piece 10, when the deformation of the first spring piece 9 reaches a certain degree, it will contact the second spring piece 10, and the second spring piece 10 needs a greater force to deform; the first spring piece 9 and the second spring piece 10 correspond to different force measurement ranges, further improving the detection accuracy of the pressure sensor.

[0047] 3. The force-bearing pressure head 3 and the fixing part 103 are locked by setting a locking rod 5 passing through the locking hole 4, and the aperture of the locking hole 4 is larger than the diameter of the locking rod 5, so that there is a gap between the locking hole 4 and the locking rod 5, thereby effectively preventing the force-bearing pressure head 3 from rotating after being stressed, and at the same time playing a guiding role in the lifting and lowering activities of the force-bearing pressure head 3, so that the lifting and lowering of the force-bearing pressure head 3 is not restricted.

[0048] As long as it does not violate the creative ideas of the present invention, any combination of the various embodiments of the present invention shall be regarded as the contents disclosed by the present invention; within the technical concept of the present invention, any combination of various simple modifications of the technical scheme and different embodiments that does not violate the creative ideas of the present invention shall be within the protection scope of the present invention.

Claims

1. A high-precision pressure sensor, characterized in that: include: A housing (1), a force-bearing pressure head (3) movably mounted on the housing (1), an elastic component and a sensing component mounted in the housing (1); The pressure head (3) comprises a pressing portion (301), a movable portion (302) connected to the pressing portion (301), and a boss portion (303) connected between the pressing portion (301) and the movable portion (302); the pressing portion (301) extends out of the housing (1), and the movable portion (302) is accommodated in the housing (1); the boss portion (303) is used to press the elastic component; The sensing component comprises a distance sensor (6) and a sensing sheet (7); the distance sensor (6) is installed in the housing (1), the sensing sheet (7) is installed on the lower surface of the boss portion (303), and the sensing sheet (7) is located directly above the distance sensor (6); The elastic component comprises a first elastic sheet (9) and a second elastic sheet (10), wherein the first elastic sheet (9) and the second elastic sheet (10) are both sleeved on the movable portion (302), and the first elastic sheet (9) abuts against the boss portion (303), and the second elastic sheet (10) abuts against the first elastic sheet (9).

2. The high-precision pressure sensor according to claim 1, characterized in that: A through hole (11) is provided in the middle of the first spring piece (9) for the movable part (302) to pass through, and a plurality of slots (12) are provided radially from the through hole (11) toward the outer circumference, and the plurality of slots (12) divide the first spring piece (9) into a plurality of slot pieces (13).

3. The high-precision pressure sensor according to claim 2, characterized in that: The structure and shape of the second elastic piece (10) are the same as those of the first elastic piece (9).

4. The high-precision pressure sensor according to claim 3, characterized in that: The thickness of the first elastic sheet (9) is smaller than the thickness of the second elastic sheet (10).

5. The high-precision pressure sensor according to claim 4, characterized in that: The thickness of the first spring sheet (9) is 1.7 mm, and the thickness of the second spring sheet (10) is 3.8 mm.

6. The high-precision pressure sensor according to claim 1, characterized in that: A first spacer ring (14) is sandwiched between the first spring sheet (9) and the lower shell (102), a second spacer ring (15) is sandwiched between the first spring sheet (9) and the second spring sheet (10), and a third spacer ring (16) is sandwiched between the second spring sheet (10) and the upper shell (101).

7. The high-precision pressure sensor according to claim 1, characterized in that: The housing (1) comprises an upper housing (101) and a lower housing (102); the pressing portion (301) extends downwardly out of the lower housing (102); and the movable portion (302) is accommodated in the upper housing (101).

8. The high-precision pressure sensor according to claim 7, characterized in that: The lower shell (102) is provided with a fixing portion (103), and the boss portion (303) is provided with a locking hole (4), and a locking rod (5) is used in the locking hole (4) to lock the pressure head (3) and the fixing portion (103); and the hole diameter of the locking hole (4) is larger than the diameter of the locking rod (5).

9. The high-precision pressure sensor according to claim 7, characterized in that: The distance sensor (6) is connected to a connecting line (8), and the connecting line (8) extends out of the upper shell (101) and the lower shell (102).

10. The high-precision pressure sensor according to claim 7, characterized in that: The upper shell (101) is provided with a receiving space (104) to accommodate the lifting and lowering movement of the movable part (302); and a connecting hole (17) is also provided in the middle of the upper shell (101) to be connected with other mechanisms.

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