A π-type multi-film phase differential displacement device

Abstract

The present invention discloses a π-type multi-membrane phase differential displacement device, which belongs to the field of pressure detection technology, and includes a blocking diaphragm, a displacement component, a mounting shell, a driving diaphragm, a pressure pipe, a diaphragm limit component, a dial and a conical transmission component. The mounting shell has through holes on the left and right surfaces, and pressure pipes are inserted in the through holes. The diaphragm limit component is installed in the mounting shell, and a translation groove is opened in the middle of the diaphragm limit component. A moving groove is opened in the diaphragm limit component, and the conical transmission component is connected in the translation groove. The driving diaphragm is installed on the left and right sides of the diaphragm limit component, and the displacement component is connected in the moving groove. The displacement component is against the side of the conical transmission component, and the upper end of the displacement component is connected with a dial, and the blocking diaphragm covers the upper surface of the mounting shell. The problem of short service life and poor measurement effect caused by the sensor in the pressure measuring device being easily damaged and the low measurement accuracy in the prior art is solved. The durability of the device and the accuracy of measurement are improved.

Description

Technical Field

[0001] The invention relates to the technical field of pressure detection, and in particular to a π-type multi-film phase differential displacement device. Background Art

[0002] When performing pressure detection, positive pressure and negative pressure are generally detected by a pressure sensor, and then the flow rate, liquid level and other indication data are calculated through the differential pressure.

[0003] Most of the existing differential pressure detection is through direct contact between the measured medium and the sensor device. However, for high temperature, high pressure, high corrosion, and high static pressure media, the sensor will be damaged. This will not only reduce the service life of the detection device, but also the medium will corrode the sensor device for a long time, which will cause the sensitivity of the sensor device to decrease and the measurement data to be inaccurate. In addition, most of the existing sensor devices cannot meet the requirements of high-precision measurement, and when the sensor device is damaged, it is easy to cause leakage of the medium, resulting in environmental pollution.

[0004] Therefore, how to provide a π-type multi-membrane phase differential displacement device to solve the defects of existing pressure measuring equipment is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] To this end, the present invention provides a π-type multi-membrane phase differential displacement device to solve the problems in the prior art of short service life and poor measurement effect caused by the sensor in the pressure measuring device being easily damaged and having low measurement accuracy.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention discloses a π-type multi-film phase differential displacement device, comprising:

[0008] The housing is installed, and through holes are opened on the left and right surfaces, and pressure pipes are inserted into the through holes;

[0009] A diaphragm stop assembly is installed in the installation housing, a translation groove is opened in the middle of the diaphragm stop assembly, a moving groove is opened in the diaphragm stop assembly, and the moving groove is arranged above the translation groove;

[0010] A conical transmission assembly, drivingly connected in the translation slot;

[0011] The driving diaphragms are arranged in pairs and installed on the left and right sides of the diaphragm limit assembly;

[0012] A displacement assembly is transmission-connected in the moving groove, the displacement assembly abuts against the side of the conical transmission assembly, and a dial is connected to the upper end of the displacement assembly;

[0013] A sealing diaphragm is covered on the upper surface of the mounting shell.

[0014] In a possible implementation, the conical transmission assembly is a truncated cone structure, and the left and right ends of the conical transmission assembly are in contact with the driving diaphragm.

[0015] In a possible implementation, the displacement component includes:

[0016] A push block, the bottom of which is against the side of the conical transmission assembly, and a driving rod is installed on the top of the push block, and the driving rod is drivingly connected to the moving groove;

[0017] A first connecting piece is mounted on the upper end of the driving rod, a second connecting piece is connected to the rear of the first connecting piece, and a connecting rod is mounted on the upper end of the second connecting piece;

[0018] A connecting member is installed on the upper end of the connecting rod. A rack is installed on the upper end of the connecting member, and the rack is meshed and connected with the dial.

[0019] In a possible implementation, the dial includes:

[0020] A bottom plate, with a slot at the bottom, the top of the connector is inserted into the slot, and a dial is installed at the upper end of the bottom plate;

[0021] A driving disc is drivingly connected to the bottom plate, a driving gear is installed at the front end of the driving disc, and the driving gear is meshed with the rack for transmission;

[0022] The pointer is mounted on the side of the driving disc.

[0023] In a possible implementation, the driving diaphragm and the blocking diaphragm are made of alloy material.

[0024] In a possible implementation, the displacement component further includes:

[0025] The rotating rods are arranged in pairs and are respectively inserted into the first connecting piece and the second connecting piece, wherein an insert block is arranged at the end of one of the rotating rods, and a displacement groove is opened at the end of the other rotating rod, in which an insert block is inserted, and a limiting groove is arranged at the end of the displacement groove;

[0026] Card blocks are arranged in pairs and installed on the insert blocks, and the card blocks are arranged in the limiting grooves;

[0027] A mounting plate, arranged at the end of the rotating rod;

[0028] A compression spring is arranged outside the rotating rod, one end of the compression spring is mounted on the surface of the mounting plate, and the other end of the compression spring is mounted with a compression plate, which is transmission-connected to the rotating rod.

[0029] In a possible implementation, the diaphragm limiting assembly is provided with a first slide groove and a second slide groove, a blocking groove is provided inside the first slide groove, a sealing plate is provided on the right surface of the diaphragm limiting assembly, a limiting member is installed in the moving groove, the limiting members are provided in pairs, and the limiting member is provided at the upper end of the conical transmission assembly;

[0030] The limiting component comprises:

[0031] A mounting member, mounted in the movable groove, the mounting member being provided with a lifting slide groove;

[0032] A moving block, which is transmission-connected in the lifting slide slot, wherein the moving block is inserted with a round rod, and a connecting plate is installed on the surface of the round rod;

[0033] A conical plug is mounted on the connecting plate, and one end of the conical plug is inserted into the bottom of the displacement assembly;

[0034] A limit spring is installed between the moving block and the connecting plate. The limit spring is sleeved on the outside of the round rod, and a limit block is installed on the round rod.

[0035] In a possible implementation, a first return spring is installed in the second slide groove, the first return spring is sleeved on the outside of the block, a baffle is provided on the side of the block, the first return spring is provided between the second slide groove and the baffle, and a conical groove is opened on the right surface of the block.

[0036] In a possible implementation, a plurality of push rods are transmission-connected in the first slide groove, a connecting disk is installed on the left surface of the push rod, a second return spring is installed on the left end of the connecting disk, the other end of the second return spring is installed in the first slide groove, and blocking blocks are arranged in pairs on the connecting disk. The blocking blocks are transmission-connected in the blocking groove, one end of the mounting rod is inserted in the connecting disk, and the other end of the mounting rod is installed in the conical transmission assembly.

[0037] The present invention avoids direct contact between the conical transmission component and the medium through the design of the driving diaphragm. The medium provides power to the driving diaphragm, and then the driving diaphragm drives the conical transmission component to move. During the movement of the conical transmission component, the displacement component rises slightly, so that the dial displays data. In this way, the medium is effectively avoided from damaging the detection device, and the driving diaphragm can buffer the pressure from the medium, allowing the conical transmission component to move slightly, thereby improving the detection accuracy. The setting of the blocking diaphragm can effectively prevent the medium from flowing from the moving groove to the outside. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0039] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0040] Figure 1 A three-dimensional diagram of the π-type multi-film phase differential displacement device provided by the present invention;

[0041] Figure 2 A cross-sectional view of the π-type multi-film phase differential displacement device provided by the present invention;

[0042] Figure 3 A stereogram of the displacement assembly provided by the present invention;

[0043] Figure 4 A cross-sectional view of a dial provided by the present invention;

[0044] Figure 5 A cross-sectional view of a displacement assembly provided by the present invention;

[0045] Figure 6 A cross-sectional view of the diaphragm limiting assembly provided by the present invention;

[0046] Figure 7 A three-dimensional diagram of a limiting component provided by the present invention;

[0047] Figure 8 A cross-sectional view of a stopper provided by the present invention;

[0048] Fig. 9 A cross-sectional view of the connection disk provided by the present invention;

[0049] In the figure: 1 blocking diaphragm; 2 displacement assembly; 21 rack; 22 second connecting piece; 23 first connecting piece; 24 push block; 25 driving rod; 26 connecting rod; 27 connecting piece; 28 displacement slot; 29 insert block; 210 limit slot; 211 clamp block; 212 rotating rod; 213 pressing spring; 214 mounting plate; 215 pressure plate; 3 mounting housing; 4 driving diaphragm; 5 pressure pipe; 6 diaphragm limit assembly; 61 limit member; 611 mounting piece; 612 displacement moving block; 613 limiting spring; 614 conical plug; 615 lifting slide; 62 blocking groove; 63 first slide; 64 second slide; 7 dial; 71 dial; 72 slot; 73 driving gear; 74 bottom plate; 75 driving disc; 76 pointer; 8 conical transmission assembly; 91 baffle; 92 first return spring; 93 block; 94 conical groove; 101 push rod; 102 second return spring; 103 blocking block; 104 connecting disc; 105 mounting rod. DETAILED DESCRIPTION

[0050] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] Please refer to Figure 1-Figure 9 Now, a π-type multi-film phase differential displacement device disclosed in the present invention is described. The present invention consists of eight parts, such as Figure 1-2 , including a blocking diaphragm 1, a displacement component 2, a mounting shell 3, a driving diaphragm 4, a pressure pipe 5, a diaphragm limit component 6, a dial 7 and a conical transmission component 8. The mounting shell 3 has through holes on the left and right surfaces, and a pressure pipe 5 is inserted in the through hole. The diaphragm limit component 6 is installed in the mounting shell 3. A translation groove is opened in the middle of the diaphragm limit component 6. A moving groove is opened in the diaphragm limit component 6, and the moving groove is arranged above the translation groove. The conical transmission component 8 is transmission-connected in the translation groove. The driving diaphragms 4 are arranged in pairs and mounted on the left and right sides of the diaphragm limit component 6. The displacement component 2 is transmission-connected in the moving groove. The displacement component 2 is against the side of the conical transmission component 8. The upper end of the displacement component 2 is connected with a dial 7. The blocking diaphragm 1 covers the upper surface of the mounting shell 3.

[0052] When the present invention is in use, the measured medium (liquid or gas) enters the interior of the installation housing 3 through the pressure pipe 5. Figure 2The left side pressure pipe 5 is a low-pressure inlet, and the right side pressure pipe 5 is a high-pressure inlet. After the measured medium enters the mounting housing 3, a pressure difference will be formed. The medium pressure is applied to the driving diaphragm 4. The deformation of the driving diaphragm 4 will drive the conical transmission assembly 8 to move to the left. During the movement of the conical transmission assembly 8, the push block 24 will be slowly squeezed, and the driving rod 25 will move upward. The driving rod 25 will apply thrust to the connecting rod 26, and the connecting rod 26 pushes the rack 21 to move upward, and then the rack 21 is engaged with the driving gear 73, driving the driving gear 73 to rotate, and the driving gear 73 will cause the driving disc 75 to rotate, thereby changing the position of the pointer 76, and the pointer 76 points to the number on the dial 71 to display the pressure value.

[0053] In a specific embodiment, the conical transmission component 8 is a truncated cone structure, and the left and right ends of the conical transmission component 8 are in contact with the driving diaphragm 4. The purpose of using a circular surface on the left side of the conical transmission component 8 is to prevent the conical end from puncturing the driving diaphragm 4, and the conical transmission component 8 is in contact with the driving diaphragm 4 to fix the conical transmission component 8 in the middle of the driving diaphragm 4 to prevent the conical transmission component 8 from failing to contact the push block 24.

[0054] In a specific embodiment, Figure 3 The displacement assembly 2 includes a rack 21, a second connecting piece 22, a first connecting piece 23, a push block 24, a driving rod 25, a connecting rod 26 and a connecting piece 27. The bottom of the push block 24 is against the side of the conical transmission assembly 8. The driving rod 25 is installed on the top of the push block 24. The driving rod 25 is connected to the moving groove in a transmission manner. The first connecting piece 23 is installed on the upper end of the driving rod 25. The second connecting piece 22 is connected to the rear of the first connecting piece 23. The connecting rod 26 is installed on the upper end of the second connecting piece 22. The connecting piece 27 is installed on the upper end of the connecting rod 26. The upper end of the connecting piece 27 is installed with a rack 21, and the rack 21 is meshed and connected with the dial 7. The second connecting piece 22 and the first connecting piece 23 are provided to set a detection limit. When the second connecting piece 22 and the first connecting piece 23 slide out of the movable groove, if the position of the dial 7 is fixed, the driving rod 25 continues to move, and the connecting rod 26 will flip over through the second connecting piece 22 and the first connecting piece 23, and the rack 21 will disengage from the driving gear 73, so that the pointer 76 cannot continue to rotate. In this way, it can be judged whether the medium will damage the driving diaphragm 4. Only when the driving diaphragm is damaged, the conical transmission assembly 8 will move a long distance and push the second connecting piece 22 and the first connecting piece 23 out of the movable groove.

[0055] In a specific embodiment, Figure 4The dial 7 includes a scale plate 71, a slot 72, a driving gear 73, a bottom plate 74, a driving disc 75 and a pointer 76. A slot 72 is provided at the bottom of the bottom plate 74, and the top of the connecting piece 27 is inserted in the slot 72. The scale plate 71 is installed on the upper end of the bottom plate 74. The driving disc 75 is connected to the bottom plate 74 in a transmission manner. A driving gear 73 is installed at the front end of the driving disc 75. The driving gear 73 is meshed with the rack 21 for transmission. The pointer 76 is installed on the side of the driving disc 75.

[0056] In a specific embodiment, the driving diaphragm 4 and the blocking diaphragm 1 are made of alloy material. The alloy material can be 316L, Hastelloy, titanium alloy, Inconel alloy, Monel alloy, etc., which solves the problem of high temperature, high pressure, high corrosion, and high static pressure of the medium that easily corrodes the metal. At the same time, the diaphragm limit assembly 6 effectively prevents the risk of leakage caused by deformation and damage of the driving diaphragm 4.

[0057] In a specific embodiment, Figure 5 The displacement assembly 2 also includes a displacement groove 28, an insert block 29, a limiting groove 210, a clamping block 211, a rotating rod 212, a clamping spring 213, a mounting plate 214 and a pressing plate 215. The rotating rods 212 are arranged in pairs and are respectively inserted in the first connecting piece 23 and the second connecting piece 22. An insert block 29 is arranged at the end of one rotating rod 212, and a displacement groove 28 is opened at the end of the other rotating rod 212. The insert block 29 is inserted in the displacement groove 28, and a limiting groove 210 is arranged at the end of the displacement groove 28. The clamping block 211 is arranged in pairs and is installed on the insert block 29. The clamping block 211 is arranged in the limiting groove 210. The mounting plate 214 is arranged at the end of the rotating rod 212. The clamping spring 213 is arranged on the outside of the rotating rod 212. One end of the clamping spring 213 is installed on the surface of the mounting plate 214. The other end of the clamping spring 213 is installed with a pressing plate 215, and the pressing plate 215 is transmission-connected to the rotating rod 212. The setting of the displacement component 2 facilitates the installation of the second connecting piece 22 and the first connecting piece 23 together, and facilitates the rotation of the second connecting piece 22 and the first connecting piece 23. When in use, the insert block 29 is inserted into the displacement slot 28, and the block 211 will enter the limit slot 210 along the displacement slot 28, and then the mounting plate 214 is rotated to make the block 211 rotate along the limit slot 210, and the rotated block 211 will be restricted by the limit slot 210 to move, thereby completing the clamping of the two rotating rods 212. After the two rotating rods 212 are connected together, the pressing plate 215 is pressed toward the second connecting piece 22 and the first connecting piece 23 through the compression of the clamping spring 213, so that the two connecting pieces will not separate during the rotation process, and it is also more convenient to separate the two connecting pieces. Not only that, the setting of the rotating rod 212 makes the rotation of the two connecting pieces more convenient.

[0058] In a specific embodiment, Figure 6-7, a first slide groove 63 and a second slide groove 64 are provided in the diaphragm limit assembly 6, a blocking groove 62 is provided inside the first slide groove 63, a sealing plate is provided on the right surface of the diaphragm limit assembly 6, a limiting member 61 is installed in the moving groove, the limiting members 61 are arranged in pairs, and the limiting members 61 are arranged at the upper end of the conical transmission assembly 8, the limiting member 61 includes a mounting member 611, a moving block 612, a limiting spring 613, a conical plug 614 and a lifting slide groove 615, the mounting member 611 is installed in the moving groove, a lifting slide groove 615 is provided on the mounting member 611, the moving block 612 is transmission-connected in the lifting slide groove 615, the moving block 612 is inserted with a round rod, a connecting plate is installed on the surface of the round rod, the conical plug 614 is installed on the connecting plate, one end of the conical plug 614 is inserted at the bottom of the displacement assembly 2, the limiting spring 613 is installed between the moving block 612 and the connecting plate, the limiting spring 613 is sleeved on the outside of the round rod, and the limiting block is installed on the round rod. The setting of the limiting member 61 facilitates the disassembly of the displacement assembly 2, reduces the resistance of the displacement assembly 2 during movement, and improves the measurement accuracy. When the limiting member 61 is in use, the conical plug 614 is inserted into the push block 24 through the conical structure of the conical plug 614. When the conical transmission assembly 8 moves, it will drive the push block 24 to move upward. At this time, the moving block 612 will move the displacement assembly 2 upward through the lifting slot 615, and the limiting spring 613 will always remain in a compressed state. When the push block 24 is installed, the round rod will be moved to compress the limiting spring 613 again. After installation, the conical plug 614 is reset and clamped to the push block 24 through the limiting spring 613, and the function of the limiting block is to ensure that the limiting spring 613 Maintain the compression state to prevent the round rod from slipping. In the existing structure, the displacement component 2 is mostly connected in a longer circular groove by transmission. In order to prevent slipping, the push block 24 is often larger than the circular groove, and the displacement component 2 is limited to a range for displacement. Moreover, when the conical transmission component 8 moves, it is easy to cause the displacement component 2 to tilt, so that the side wall of the displacement component 2 will have a certain friction with the circular groove. This friction will affect the up and down transmission of the displacement component 2, and then cause the measurement data to have a certain deviation. The setting of the limiting component 61 can not only ensure that the conical transmission component 8 will not drive the displacement component 2 to move slightly, but also make the displacement component 2 not tilt and then move up and down, so as to ensure that the measurement data is more accurate.

[0059] In a specific embodiment, Figure 8, a first return spring 92 is installed in the second slide groove 64, the first return spring 92 is sleeved on the outside of the block 93, a baffle 91 is arranged on the side of the block 93, the first return spring 92 is arranged between the second slide groove 64 and the baffle 91, and a conical groove 94 is opened on the right surface of the block 93. When the conical transmission assembly 8 moves to the left, the left end of the conical transmission assembly 8 will be stuck in the conical groove 94. When the conical transmission assembly 8 continues to move to the left, the block 93 moves to the left and drives the first return spring 92 to compress. The first return spring 92 is used to reset the conical transmission assembly 8 after measurement. The setting of the block 93 is to prevent the medium from entering the translation groove to damage the conical transmission assembly 8 when the driving diaphragm 4 is damaged, and the design of the block 93 can increase the contact area with the driving diaphragm 4, and more effectively prevent the driving diaphragm 4 from being damaged.

[0060] In a specific embodiment, Fig. 9 A plurality of push rods 101 are transmission-connected in the first slide groove 63, a connecting disk 104 is installed on the left surface of the push rod 101, a second return spring 102 is installed on the left end of the connecting disk 104, the other end of the second return spring 102 is installed in the first slide groove 63, and the blocking blocks 103 are arranged in pairs on the connecting disk 104. The blocking blocks 103 are transmission-connected in the blocking groove 62, one end of the mounting rod 105 is inserted in the connecting disk 104, and the other end of the mounting rod 105 is installed in the conical transmission assembly 8. The deformation of the driving diaphragm 4 will drive the push rod 101 to move, and the movement of the driving push rod 101 will move the connecting disk 104. The movement of the connecting disk 104 will squeeze the second reset spring 102 for compression, and the second reset spring 102 is used for detection and reset. The movement of the connecting disk 104 will also drive the mounting rod 105 to move, thereby causing the conical transmission assembly 8 to move. During the movement of the connecting disk 104, the blocking block 103 will move in the blocking groove 62. The design of the blocking block 103 not only facilitates the movement of the connecting disk 104, but also can effectively prevent the driving diaphragm 4 from being damaged and causing the medium to leak into the translation groove. The right end of the push rod 101 passes through the first slide groove 63.

[0061] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A π-type multi-film phase differential displacement device, characterized in that: include: An installation housing (3) is provided with through holes on the left and right surfaces, and pressure pipes (5) are inserted into the through holes; A diaphragm stop assembly (6) is installed in the installation housing (3), a translation groove is provided in the middle of the diaphragm stop assembly (6), a moving groove is provided in the diaphragm stop assembly (6), and the moving groove is arranged above the translation groove; A conical transmission assembly (8) drivingly connected in the translation groove; The driving diaphragms (4) are arranged in pairs and installed on the left and right sides of the diaphragm limit assembly (6); A displacement assembly (2) is transmission-connected in the movable groove, the displacement assembly (2) abuts against the side of the conical transmission assembly (8), and a dial (7) is connected to the upper end of the displacement assembly (2); A sealing membrane (1) covering the upper surface of the mounting housing (3); The diaphragm limiting assembly (6) is provided with a first sliding groove (63) and a second sliding groove (64), a blocking groove (62) is provided inside the first sliding groove (63), a sealing plate is provided on the right surface of the diaphragm limiting assembly (6), a limiting member (61) is installed in the movable groove, the limiting members (61) are provided in pairs, and the limiting members (61) are provided at the upper end of the conical transmission assembly (8); The limiting component (61) comprises: A mounting member (611) is mounted in the movable groove, and a lifting slide groove (615) is formed on the mounting member (611); A moving block (612) is drivingly connected to the lifting slide groove (615), wherein a round rod is inserted into the moving block (612), and a connecting plate is installed on the surface of the round rod; A conical plug (614) is mounted on the connecting plate, one end of the conical plug (614) being inserted into the bottom of the displacement assembly (2); A limit spring (613) is installed between the moving block (612) and the connecting plate. The limit spring (613) is sleeved on the outside of the round rod, and a limit block is installed on the round rod.

2. The π-type multi-film phase differential shift device according to claim 1, characterized in that: The conical transmission component (8) is a truncated cone structure, and the left and right ends of the conical transmission component (8) are in contact with the driving diaphragm (4).

3. The π-type multi-film phase differential shift device according to claim 1, characterized in that: The displacement component (2) comprises: A push block (24), the bottom of which is against the side of the conical transmission assembly (8), and a driving rod (25) is installed on the top of the push block (24), and the driving rod (25) is drivingly connected to the moving groove; A first connecting piece (23) is mounted on the upper end of the driving rod (25); a second connecting piece (22) is connected to the rear of the first connecting piece (23); a connecting rod (26) is mounted on the upper end of the second connecting piece (22); A connecting member (27) is mounted on the upper end of the connecting rod (26); a rack (21) is mounted on the upper end of the connecting member (27); and the rack (21) is meshingly connected to the dial (7).

4. The π-type multi-film phase differential shift device according to claim 3, characterized in that: The dial (7) comprises: A bottom plate (74) having a slot (72) at the bottom, the top end of the connecting member (27) being inserted into the slot (72), and a dial (71) being mounted on the upper end of the bottom plate (74); A driving disc (75) is drivingly connected to the bottom plate (74); a driving gear (73) is mounted on the front end of the driving disc (75); the driving gear (73) is meshed with the rack (21) for transmission; The pointer (76) is mounted on the side of the driving disc (75).

5. The π-type multi-film phase differential shift device according to claim 1, characterized in that: The driving diaphragm (4) and the blocking diaphragm (1) are made of alloy material.

6. The π-type multi-film phase differential shift device according to claim 3, characterized in that: The displacement assembly (2) further comprises: The rotating rods (212) are arranged in pairs and are respectively inserted into the first connecting piece (23) and the second connecting piece (22), wherein an insert block (29) is provided at the end of one of the rotating rods (212), and a displacement groove (28) is opened at the end of the other rotating rod (212), an insert block (29) is inserted in the displacement groove (28), and a limiting groove (210) is provided at the end of the displacement groove (28); The clamping blocks (211) are arranged in pairs and mounted on the inserting block (29); the clamping blocks (211) are arranged in the limiting grooves (210); A mounting plate (214) disposed at the end of the rotating rod (212); A compression spring (213) is arranged outside the rotating rod (212); one end of the compression spring (213) is mounted on the surface of the mounting plate (214); a compression plate (215) is mounted on the other end of the compression spring (213); and the compression plate (215) is drivingly connected to the rotating rod (212).

7. The π-type multi-film phase differential shift device according to claim 1, characterized in that: A first return spring (92) is installed in the second slide groove (64). The first return spring (92) is sleeved on the outside of the stop block (93). A baffle plate (91) is provided on the side of the stop block (93). The first return spring (92) is arranged between the second slide groove (64) and the baffle plate (91). A conical groove (94) is opened on the right surface of the stop block (93).

8. The π-type multi-film phase differential shift device according to claim 1, characterized in that: A plurality of push rods (101) are transmission-connected in the first slide groove (63); a connecting disk (104) is installed on the left surface of the push rod (101); a second return spring (102) is installed on the left end of the connecting disk (104); the other end of the second return spring (102) is installed in the first slide groove (63); blocking blocks (103) are arranged in pairs on the connecting disk (104); the blocking blocks (103) are transmission-connected in the blocking groove (62); one end of a mounting rod (105) is inserted in the connecting disk (104); the other end of the mounting rod (105) is installed in the conical transmission assembly (8).

Images