A sampling cylinder for an on-line monitoring device of dissolved gas in oil

Abstract

The utility model provides a kind of sampling cylinder for oil dissolved gas on-line monitoring device, including sealing jar, piston rod and electric linear mechanism;One end of piston rod is equipped with piston, and piston is sealed sliding in sealing jar;The other end of piston rod is connected with electric linear mechanism, and the end of sealing jar away from electric linear mechanism is equipped with material hole;Sealing jar is equipped with guide member for guiding linear motion of piston rod;The utility model utilizes guide member to ensure the linearity of piston rod movement, so as to ensure that piston can be always arranged concentrically with sealing jar in movement process, avoid uneven wear of piston to cause sealing failure, affect normal use of sampling cylinder.

Description

Technical Field

[0001] This utility model belongs to the field of transformer oil online monitoring technology, specifically relating to a sampling cylinder for an online monitoring device for dissolved gases in oil. Background Technology

[0002] Online monitoring of transformer oil is crucial for diagnosing internal transformer faults. During transformer operation, internal discharges or overheating can cause aging of transformer oil and solid insulating materials such as insulating paper, generating fault-specific gases that dissolve in the transformer oil. Different types of faults generate different gases; by detecting the composition and concentration of these dissolved gases, the nature and severity of the transformer fault can be assessed.

[0003] In the online monitoring of transformer oil, a sampling cylinder is needed to perform functions such as sampling transformer oil, vacuuming during oil-gas separation, and sampling of the separated gas. Current sampling cylinders consist of a sealed cylinder, a piston assembly slidingly disposed within the sealed cylinder, and a push rod motor that drives the piston assembly to reciprocate. The piston assembly is threadedly connected to a push rod on the push rod motor, allowing the push rod to drive the piston assembly to reciprocate. However, in actual use, it has been found that due to the gap between the internal and external threads in the threaded connection, the concentricity of the piston assembly and the push rod cannot be guaranteed. Therefore, the piston assembly is prone to deviating from the centerline of the sealed cylinder during operation, leading to uneven wear and causing seal failure between the piston assembly and the sealed cylinder. In severe cases, this can even result in cylinder scoring. Utility Model Content

[0004] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a sampling cylinder for an online monitoring device for dissolved gases in oil. The cylinder has an added guide component, which is used to ensure the straightness of the piston rod movement, thereby ensuring the concentricity of the piston and the sealing cylinder. This prevents the piston from deviating from the center line of the sealing cylinder during movement and causing uneven wear, and ensures the sealing effectiveness during the piston sliding process.

[0005] To achieve the above and other related objectives, this utility model provides a sampling cylinder for an online monitoring device for dissolved gases in oil, comprising a sealed cylinder, a piston rod, and an electric linear mechanism; one end of the piston rod is provided with a piston, and the piston slides within the sealed cylinder in a sealed manner; the other end of the piston rod is connected to the electric linear mechanism, and the end of the sealed cylinder away from the electric linear mechanism is provided with a material hole; a guide component is provided inside the sealed cylinder to guide the linear movement of the piston rod; this utility model utilizes the guide component to ensure the straightness of the piston rod movement, thereby ensuring that the piston is always concentrically positioned with the sealed cylinder during movement, avoiding uneven wear of the piston that could lead to seal failure and affect the normal use of the sampling cylinder.

[0006] Preferably, the guide is a linear bearing or a guide sleeve, which the user can choose according to their needs.

[0007] Preferably, a wear-resistant ring is fitted on the piston to reduce piston wear and jamming by utilizing the guiding effect of the wear-resistant ring.

[0008] Preferably, the electric linear mechanism is a lead screw motor, which includes a rotary motor, a lead screw, and a lead screw nut threaded onto the lead screw; the rotary motor is fixedly connected to the sealing cylinder, and the piston rod has an axial clearance hole at one end near the rotary motor to avoid the lead screw; the lead screw nut is fixedly connected to the piston rod, and the lead screw nut is circumferentially fixed to the sealing cylinder and slides in the axial direction of the piston rod.

[0009] Preferably, the lead screw nut is fixedly connected to the piston rod via a guide seat; a first limiting member is provided on the outer wall of the guide seat, and a second limiting member is provided on the inner wall of the sealing cylinder to cooperate with the first limiting member; the first limiting member and the second limiting member slide in the axial direction of the piston rod, and the two cooperate to restrict the relative rotation of the guide seat and the sealing cylinder; this application uses a guide seat to connect the piston rod in the sealing cylinder and the lead screw nut in the lead screw motor, effectively avoiding the need for secondary processing of the lead screw nut due to the size mismatch between the sealing cylinder and the lead screw nut.

[0010] Preferably, the first limiting member is an axial slider, and the second limiting member is an axial groove that cooperates with the axial slider; or, the first limiting member is an axial groove, and the second limiting member is an axial slider that cooperates with the axial groove.

[0011] Preferably, the cross-section of the axial slider is semi-circular, trapezoidal, or rectangular, which the user can choose according to their needs.

[0012] Preferably, the sealed cylinder is equipped with a reset sensor to detect whether the piston has been reset to the initial position, so as to ensure the normal operation of subsequent sampling actions.

[0013] Preferably, the reset sensor includes a photoelectric switch and a test component that cooperates with the photoelectric switch. The test component is mounted on a lead screw nut or a guide seat. In this way, the photoelectric switch can detect whether the test component has moved to a preset position, so as to determine whether the piston has reset to the initial stroke position.

[0014] Preferably, the outer wall of the sealing cylinder is provided with a mounting groove for installing a photoelectric switch, and a dust cover is detachably fixed to the mounting groove; the mounting groove can effectively reduce the difficulty of assembling and disassembling the photoelectric switch, while the dust cover can prevent external dust from contaminating the photoelectric switch and affecting the accuracy of photoelectric switch detection.

[0015] As described above, the sampling cylinder of this utility model for an online monitoring device of dissolved gases in oil has the following beneficial effects:

[0016] This application adds a guide component inside the sealing cylinder to ensure the straightness of the piston rod during sliding, thereby ensuring the coaxiality between the piston and the sealing cylinder during the piston's movement. This prevents uneven wear (i.e., uneven wear) from occurring during the piston's movement, which would affect the sealing performance between the piston and the inner wall of the sealing cylinder. At the same time, it also prevents direct contact between the piston and the inner wall of the sealing cylinder, which could cause scratches on the inner wall of the sealing cylinder and abnormal noise.

[0017] In addition, the wear-resistant ring added to the outside of the piston can guide the linear reciprocating motion of the piston, thereby reducing uneven wear and jamming of the piston and preventing damage to the piston outer seal due to uneven wear. At the same time, the wear-resistant ring can also prevent direct metal-to-metal contact between the piston and the inner wall of the sealing cylinder, thereby preventing the heat generated by metal-to-metal friction from burning the piston outer seal and ensuring the service life of the seal.

[0018] Finally, this application provides an installation groove on the outer wall of the sealing cylinder for installing a photoelectric switch, which effectively reduces the difficulty of disassembling and assembling the photoelectric switch and improves the efficiency of disassembling and assembling the photoelectric switch. Attached Figure Description

[0019] Figure 1 A three-dimensional view of the sampling cylinder for an online monitoring device for dissolved gases in oil provided by this utility model.

[0020] Figure 2 for Figure 1 Top view.

[0021] Figure 3 for Figure 2 AA-direction cross-section.

[0022] Figure 4 This is a three-dimensional exploded view of the sampling cylinder.

[0023] Figure 5 This is a schematic diagram showing the separation of the cylinder head and cylinder body in the sampling cylinder.

[0024] Figure 6 This is a schematic diagram showing the arrangement of the piston's sealing ring and wear ring.

[0025] Figure 7 This is an isometric half-section view of the cylinder block.

[0026] Figure 8 This is an exploded view showing the fit between the guide seat and the cylinder body.

[0027] Figure 9 This is a schematic diagram of the structure of a photoelectric switch in one embodiment.

[0028] Explanation of reference numerals in the attached figures

[0029] 1. Sealing cylinder, suction hole 1a, discharge hole 1b, cylinder body 11, first channel 111, second channel 112, guide seat sliding hole 1121, axial groove 11211, measured part clearance hole 1122, mounting cavity 113, cylinder head 12, dust cover 13. 2. Piston, piston rod 3, electric linear mechanism 4, rotary motor 41, lead screw 42, lead screw nut 43, guide seat 44, axial slider 441, guide component 5, sealing ring 6, wear-resistant ring 7, photoelectric switch 81, switch body 811, transmitter 812, receiver 813, measured part 82. Detailed Implementation

[0030] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification.

[0031] Please see Figures 1 to 9 It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and are not intended to limit the scope of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of this invention, should still fall within the scope of the disclosed technical content. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of this invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this invention.

[0032] This embodiment provides a sampling cylinder for an online monitoring device for dissolved gases in oil, capable of sampling transformer oil, vacuuming during oil-gas separation, or sampling of separated gases; such as... Figures 1 to 3As shown, the sampling cylinder includes a sealing cylinder 1, a piston 2 that slides axially within the sealing cylinder 1, a piston rod 3 coaxially arranged with the piston 2, and an electric linear mechanism 4 that drives the piston rod 3 to move linearly back and forth. The piston 2 is fitted with a sealing ring 6. When the piston 2 slides axially within the sealing cylinder 1 under the drive of the piston rod 3, the sealing ring 6 is compressed and deformed to seal the gap between the piston 2 and the inner wall of the sealing cylinder 1. The sealing cylinder 1 is equipped with a guide 5 to guide the linear movement of the piston rod 3, and a material hole is provided at the end of the sealing cylinder 1 away from the electric linear mechanism 4. Thus, when the electric linear mechanism... When the piston rod 3 drives the piston 2 to reciprocate linearly, the fluid (gas or liquid) can be drawn into or discharged from the sealing cylinder 1 through the material hole. During this process, the guide 5 can effectively ensure the straightness of the piston rod 3 during sliding, so that the piston 2 can always remain coaxial with the sealing cylinder 1 during the movement, avoiding uneven wear of the piston 2 during the movement, which would affect the sealing performance between the piston 2 and the inner wall of the sealing cylinder 1. At the same time, it can also avoid direct metal-to-metal contact between the piston 2 and the inner wall of the sealing cylinder 1, which would cause scratches on the inner wall of the sealing cylinder 1 and abnormal noise.

[0033] It should be noted that the electric linear mechanism 4 and the sealing cylinder 1 can be fixedly connected or set separately, and there is no limitation on this. In this embodiment, the electric linear mechanism 4 and the sealing cylinder 1 are directly fixedly connected to form an integrated sampling cylinder structure, which facilitates the overall assembly and disassembly of the sampling cylinder.

[0034] It is understood that the piston 2 and the piston rod 3 can be integrally formed or separate structures, and there is no limitation on this. When the piston 2 and the piston rod 3 are separate, they can be connected by bolts, clips, etc. In this embodiment, the piston 2 and the piston rod 3 are preferably integrally formed to ensure the coaxiality of the piston 2 with the sealing cylinder 1 during operation.

[0035] like Figure 3 and Figure 6 As shown, a wear-resistant ring 7 is also fitted around the piston 2. The wear-resistant ring 7 is made of high-strength, wear-resistant materials with a low coefficient of friction, such as polytetrafluoroethylene or phenolic resin-reinforced fabric. The wear-resistant ring 7 can not only reduce the friction and wear between the piston 2 and the inner wall of the sealing cylinder 1, but also provide precise guidance, further ensuring the coaxiality of the piston 2 and the sealing cylinder 1 during the sliding process, so as to avoid uneven wear when the piston 2 slides, which would cause the sealing ring 6 outside the piston 2 to fail due to uneven wear. In this embodiment, the piston 2 is provided with two sealing rings 6 and one wear-resistant ring 7, and the wear-resistant ring 7 is located between the two sealing rings 6.

[0036] It is understood that the guide 5 can be a linear bearing or a guide sleeve, and there is no limitation on this, as long as the straightness of the piston rod 3 movement can be guaranteed; in this embodiment, the guide 5 is preferably a linear bearing, so as to reduce the friction between the piston rod 3 and the guide 5, avoid excessive friction between the two to generate a large amount of heat, which would cause the temperature inside the sealing cylinder 1 to rise and accelerate the aging of the sealing ring 6.

[0037] Since linear bearings are divided into flanged linear bearings and non-flange linear bearings, when a non-flange linear bearing is used, it is usually assembled in the sealing cylinder 1 by an interference fit, which presents a problem of inconvenience in disassembly and assembly. To facilitate the disassembly and assembly of the linear bearing, the linear bearing in this embodiment is a flanged linear bearing, which includes a linear bearing body and a mounting flange formed at one end of the linear bearing body. At this time, as... Figure 2 and Figure 3 As shown, the sealing cylinder 1 includes a cylinder body 11 and a cylinder cover 12. The cylinder cover 12 is fixed to the end of the cylinder body 11 away from the electric linear mechanism 4 by bolts, and the cylinder cover 12 is provided with a material hole. The through channel in the cylinder body 11 includes a first channel 111 for the piston 2 to slide and a second channel 112 for embedding the linear bearing body. The first channel 111 and the second channel 112 are connected to form a stepped hole, and a stepped structure for installing the linear bearing flange is formed between the first channel 111 and the second channel 112. In this way, when the flange-type linear bearing is coaxially inserted into the second channel 112 through the first channel 111, the flange of the flange-type linear bearing can be fixed to the stepped structure by bolts to complete the installation of the flange-type linear bearing, which has the advantage of convenient installation.

[0038] As a preferred design, such as Figure 5 As shown, a sealing ring 6 needs to be provided at the end of the cylinder body 11 facing the cylinder head 12. In this way, when the cylinder head 12 is bolted to the cylinder body 11, the sealing ring 6 between the cylinder head 12 and the cylinder body 11 can deform to seal the gap between them, so as to prevent the fluid drawn into the cylinder body 11 from leaking through the gap between the cylinder head 12 and the cylinder body 11.

[0039] As a preferred design, such as Figure 1 As shown, the material holes on the cylinder head 12 include a suction hole 1a and a discharge hole 1b. When there is only one material hole, a three-way valve can be installed at the material hole so that the remaining two ports of the three-way valve can be used as the feed port and the discharge port, respectively.

[0040] In the above-mentioned sampling cylinder, the electric linear mechanism 4 has various structural forms, including but not limited to a lead screw motor or a linear motor with a push rod. In this embodiment, the electric linear mechanism 4 preferably adopts a lead screw motor.

[0041] Specifically, such as Figure 3 and Figure 4As shown, the lead screw motor includes a rotary motor 41, a lead screw 42, and a lead screw nut 43 threaded onto the lead screw 42. The rotor of the rotary motor 41 drives the lead screw 42 to rotate, and the rotary motor 41 is coaxially fixed to the end of the cylinder body 11 away from the cylinder head 12 by bolts. The outer diameter of the piston rod 3 is larger than the outer diameter of the lead screw 42, and the end of the piston rod 3 near the rotary motor 41 is provided with an axial clearance hole 3a for avoiding the lead screw 42. The lead screw nut 43 is fixedly connected to the piston rod 3, and the lead screw nut 43 is circumferentially fixed in the sealed cylinder 1 and can slide relative to the sealed cylinder 1 in the axial direction of the piston rod 3. Thus, when the rotary motor 41 drives the lead screw 42 to rotate, the lead screw nut 43 can move linearly along the lead screw 42 to drive the piston rod 3 and piston 2 to move linearly back and forth in the sealed cylinder 1.

[0042] Furthermore, the lead screw nut 43 is fixedly connected to the piston rod 3 via the guide seat 44; wherein, the guide seat 44 is coaxially fixed to the end of the piston rod 3 away from the piston 2 by bolts, and the lead screw nut 43 is bolted to the guide seat 44 to achieve relative fixation of the lead screw nut 43, the guide seat 44 and the piston rod 3; a first limiting member is provided on the outer wall of the guide seat 44, and a second limiting member is provided on the inner wall of the sealing cylinder 1; the first limiting member and the second limiting member slide in the axial direction of the piston rod 3, and the two cooperate to limit The guide seat 44 and the sealing cylinder 1 are restricted from relative rotation; wherein, the first limiting member and the second limiting member are mutually cooperating axial slider 441 and axial groove 11211 or two mutually cooperating planes (e.g., the guide seat 44 has a plane one, and the sealing cylinder 1 has a plane two that cooperates with plane one, and the two planes cooperate to restrict the relative rotation between the guide seat 44 and the sealing cylinder 1); in this embodiment, the first limiting member is the axial slider 441, and the second limiting member is the axial groove 11211 that cooperates with the axial slider 441 (e.g., the guide seat 44 has a plane one, and the sealing cylinder 1 has a plane two that cooperates with plane one, and the two planes cooperate to restrict the relative rotation between the guide seat 44 and the sealing cylinder 1); Figure 8 (As shown).

[0043] It is understood that the cross-sectional shape of the axial slider 441 includes, but is not limited to, various shapes such as semi-circle, trapezoid, or rectangle, and users can set it according to their actual situation.

[0044] Since the sampling cylinder needs to frequently pump fluid into and out of the sealed cylinder 1, a reset sensor needs to be installed inside the sealed cylinder 1 to ensure the accuracy of each pumping stroke. The reset sensor detects the position of the lead screw nut 43 or the guide seat 44 to determine whether the piston 2 has reset to the initial stroke position. In this embodiment, the reset sensor includes a position detection switch installed inside the cylinder body 11 and a detection element 82 that cooperates with the position detection switch. Based on the consideration of arrangement stability, the detection element 82 is preferably installed on the guide seat 44. At this time, if Figure 7 and Figure 8As shown, the second channel 112 includes a guide seat sliding hole 1121 for sliding the guide seat 44 and a test piece avoidance hole 1122 for avoiding the test piece 82.

[0045] It is understood that the structure of the position detection switch is diverse, including but not limited to various ranging sensors or various proximity switches; in this embodiment, the position detection switch preferably adopts photoelectric switch 81.

[0046] The structural forms of the photoelectric switch 81 include, but are not limited to, the following:

[0047] The first structural form: such as Figure 9 As shown, the photoelectric switch 81 is a through-beam photoelectric switch, which includes a switch body 81 and a transmitter 812 and a receiver 813 disposed opposite to each other on the switch body 811. The light beam emitted by the transmitter 82 is directly directed to the receiver. When the test object 82 moves between the transmitter 812 and the receiver 813 to block the light beam, the receiver 813 cannot receive the light signal. At this time, the piston 2 reaches the initial stroke position.

[0048] The second structural form: the photoelectric switch is a reflective photoelectric switch, which includes a transmitter 812, a receiver 813 and a reflective surface. The light beam emitted by the transmitter 812 is continuously received by the receiver 813 after encountering the reflective surface. When the measured object 82 enters the light beam path, it will block or change the reflection of the light beam. The receiver 813 cannot receive enough light signal. At this time, the piston 2 reaches the initial stroke position.

[0049] To reduce the installation difficulty of photoelectric switch 81, such as Figure 4 , Figure 7 and Figure 8 As shown, a mounting groove 113 communicating with the second channel 112 can be opened on the outer wall of the cylinder 11. The mounting groove 113 is used to install the photoelectric switch 81, and a dust cover 13 can be detachably fixed at the mounting groove 113.

[0050] Preferably, in this embodiment, the mounting groove 113 is located on the side of the test piece's clearance hole 1122 near the piston 2 (i.e., the left side), and the two are interconnected in the axial direction of the piston rod 3; at this time, the photoelectric switch 81 can be directly set at the bottom of the mounting groove 113.

[0051] In summary, this utility model effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0052] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A sampling cylinder for an online monitoring device for dissolved gases in oil, comprising a sealed cylinder (1), a piston rod (3), and an electric linear mechanism (4); one end of the piston rod (3) is provided with a piston (2), and the piston (2) slides sealed within the sealed cylinder (1); the other end of the piston rod (3) is connected to the electric linear mechanism (4), and the end of the sealed cylinder (1) away from the electric linear mechanism is provided with a material hole; characterized in that, The sealing cylinder (1) is provided with a guide (5) to guide the linear movement of the piston rod (3).

2. The sampling cylinder for an online monitoring device for dissolved gases in oil according to claim 1, characterized in that, The guide element (5) is a linear bearing or a guide sleeve.

3. A sampling cylinder for an online monitoring device for dissolved gases in oil according to claim 1, characterized in that, The piston (2) is fitted with a wear-resistant ring (7).

4. A sampling cylinder for an online monitoring device for dissolved gases in oil according to claim 1, 2, or 3, characterized in that, The electric linear mechanism (4) is a lead screw motor, which includes a rotary motor (41), a lead screw (42), and a lead screw nut (43) threaded onto the lead screw (42). The rotary motor (41) is fixedly connected to the sealing cylinder (1), and the piston rod (3) has an axial clearance hole (3a) at one end near the rotary motor (41) for avoiding the lead screw (42). The lead screw nut (43) is fixedly connected to the piston rod (3), and the lead screw nut (43) is circumferentially fixed to the sealing cylinder (1) and slides in the axial direction of the piston rod (3).

5. A sampling cylinder for an online monitoring device for dissolved gases in oil according to claim 4, characterized in that, The lead screw nut (43) is fixedly connected to the piston rod (3) through the guide seat (44); the outer wall of the guide seat (44) is provided with a first limiting member, and the inner wall of the sealing cylinder (1) is provided with a second limiting member that cooperates with the first limiting member; the first limiting member and the second limiting member slide in the axial direction of the piston rod (2), and the two cooperate to restrict the relative rotation of the guide seat (44) and the sealing cylinder (1).

6. A sampling cylinder for an online monitoring device for dissolved gases in oil according to claim 5, characterized in that, The first limiting member is an axial slider (441), and the second limiting member is an axial groove (11211) that cooperates with the axial slider (441); or, the first limiting member is an axial groove (11211), and the second limiting member is an axial slider (441) that cooperates with the axial groove (11211).

7. A sampling cylinder for an online monitoring device for dissolved gases in oil according to claim 6, characterized in that, The cross-section of the axial slider (441) is semi-circular, trapezoidal, or rectangular.

8. A sampling cylinder for an online monitoring device for dissolved gases in oil according to claim 5, characterized in that, The sealing cylinder (1) is equipped with a reset sensor.

9. A sampling cylinder for an online monitoring device for dissolved gases in oil according to claim 8, characterized in that, The reset sensor includes a photoelectric switch (81) and a test component (82) that cooperates with the photoelectric switch (81). The test component (82) is mounted on a lead screw nut (43) or a guide seat (44).

10. A sampling cylinder for an online monitoring device for dissolved gases in oil according to claim 9, characterized in that, The outer wall of the sealing cylinder (1) is provided with a mounting groove (113) for installing a photoelectric switch (81), and a dust cover (13) is detachably fixed at the mounting groove (113).

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