Float coupling structure

Abstract

To improve joint strength due to welding of a float and a mounting member.SOLUTION: A float coupling structure comprises: a hollow float 45; a mounting member 50 that has a base 51 provided on the outside of the float 45 and having a contact surface 51a that contacts an external surface 45c of the float 45 and is used to be coupled to a lever 46, and a plurality of protrusion parts 53 protruding from the contact surface 51a and penetrating the float 45; a first welding part 61 that welds the base 51 to the external surface 45c of the float 45; and a plurality of second welding parts 62 that weld each of the plurality of protrusion part 53 to an internal surface 45d of the float 45.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The technology of the present disclosure relates to a connecting structure of a float. [Background technology]

[0002] A connecting structure for a float that rises and falls according to the liquid level is disclosed, for example, in Patent Document 1. The connecting structure disclosed in Patent Document 1 is provided in a liquid pressure-feeding device and includes a float and an attachment member joined to the float. The attachment member is welded to the float and is connected to a lever, which is the object to be connected. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-43944 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the above-mentioned float connection structure is used in a large condensate trap that discharges large volumes of condensate under high temperature and high pressure conditions, the welding strength between the mounting member and the float may not be sufficient, and in such cases there is a risk that the mounting member may come off the float. For this reason, there is a demand for improving the welding joint strength.

[0005] The technology of the present disclosure has been made in consideration of the above circumstances, and its purpose is to improve the joint strength between the float and the mounting member by welding. [Means for solving the problem]

[0006] The float connection structure of the present disclosure comprises a hollow float, an attachment member, an outer weld, and an inner weld. The attachment member is provided on the outside of the float and has a contact surface that contacts the outer surface of the float, a base for connecting to an object to be connected, and a plurality of protrusions that protrude from the contact surface and penetrate the float. The outer weld welds the base to the outer surface of the float. The inner weld welds each of the plurality of protrusions to the inner surface of the float. [Effects of the Invention]

[0007] According to the above-described float connection structure, the joining strength between the float and the mounting member by welding can be improved. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view showing a drain trap in a closed state. [Figure 2] FIG. 2 is a cross-sectional view showing the drain trap in an open state. [Figure 3] FIG. 3 is a cross-sectional view showing the connecting structure of the float. [Figure 4] FIG. 4 is a plan view showing the float as viewed from the lever side. [Figure 5] FIG. 5 is a perspective view showing the mounting member as viewed from the protruding portion side. DETAILED DESCRIPTION OF THE INVENTION

[0009] Exemplary embodiments will be described in detail below with reference to the drawings. Figure 1 is a cross-sectional view showing a drain trap 100 in a closed state. Figure 2 is a cross-sectional view showing the drain trap 100 in an open state.

[0010] The drain trap 100 is installed in a steam pipe of a steam system in a high-temperature, high-pressure environment, for example, to prevent the outflow of steam while allowing a large amount of drain generated by condensation of the steam to flow out. The drain trap 100 is provided with a connecting structure for a float 45. Specifically, the drain trap 100 includes a housing 1, a screen 3, and a valve mechanism 4.

[0011] Hereinafter, the symbol "Up" in the drawings means the upper side in the up-down direction, the symbol "Dw" means the lower side in the up-down direction, the symbol "Rh" means the right side in the left-right direction, and the symbol "Lf" means the left side in the left-right direction. Note that the left-right direction indicates the left and right when viewing the float 45 from the side of the lever 46, which will be described later.

[0012] A flow path 2 through which the drain flows is formed in the housing 1. In this example, the flow path 2 is formed by an inlet path 21, a capture path 22, a communication path 23, a storage chamber 24, and an outlet path 25.

[0013] One end of the inlet channel 21 opens to the outside, specifically in the horizontal direction. The other end of the inlet channel 21 is connected to the capture channel 22. A screen 3 is provided in the capture channel 22. The capture channel 22 communicates with the storage chamber 24 via a communication channel 23. More specifically, one end of the capture channel 22 is connected to the inlet channel 21, and the other end of the capture channel 22 is closed by a closure plate 13. The communication channel 23 is connected to the side of the capture channel 22 and the bottom of the storage chamber 24. In other words, the capture channel 22 is located below the storage chamber 24.

[0014] Drain is temporarily stored in the storage chamber 24. One end of the outflow path 25 is connected to the storage chamber 24, more specifically, connected to a lower portion of the side of the storage chamber 24. The other end of the outflow path 25 opens to the outside, more specifically, opens horizontally. In the flow path 2, drain that has flowed into the inflow path 21 from the outside flows through the capture path 22, the communication path 23, and the outflow path 25 in this order, and then flows out to the outside.

[0015] More specifically, the housing 1 has a lower portion 11 and an upper portion 12 that are connected to each other in the vertical direction. The lower portion 11 and the upper portion 12 are joined by bolting. The lower portion 11 is formed with an inlet channel 21, a capture channel 22, a communication channel 23, and an outlet channel 25. The storage chamber 24 is formed across the lower portion 11 and the upper portion 12. The housing 1 is provided with a plurality of legs 14.

[0016] As described above, the screen 3 is provided in the capture passage 22 and captures foreign matter in the drain flowing through the capture passage 22. The screen 3 is formed in a cylindrical shape extending in the axial direction of the capture passage 22. In the capture passage 22, the drain that has flowed in from the inlet passage 21 passes through the peripheral wall of the screen 3 from the inside to the outside. As the drain passes through the peripheral wall of the screen 3, foreign matter in the drain is captured.

[0017] The valve mechanism 4 is provided in the flow path 2 and opens and closes the flow path 2. Specifically, the valve mechanism 4 is provided in the storage chamber 24 and opens and closes the connection between the storage chamber 24 and the outflow path 25. The valve mechanism 4 has a case 41 in which a valve hole 42 is formed, a valve element 43 that opens and closes the valve hole 42, and a driver 44 that drives the valve element 43.

[0018] Case 41 is disposed at a connection portion between storage chamber 24 and outflow path 25. Case 41 is provided so that its internal space communicates with the aforementioned connection portion (i.e., outflow path 25). Valve hole 42 penetrates case 41 from the inside to the outside, and communicates the internal space of case 41 with storage chamber 24. In other words, storage chamber 24 and outflow path 25 communicate with each other via valve hole 42. In this example, a pair of valve holes 42 aligned in the vertical direction are provided, and a pair of valve bodies 43 are provided to open and close each of the pair of valve holes 42.

[0019] More specifically, of the pair of valve bodies 43, the valve body 43 corresponding to the upper valve hole 42 is located in the internal space of the case 41, and the valve body 43 corresponding to the lower valve hole 42 is located outside the case 41. The pair of valve bodies 43 move up and down to open and close the pair of valve holes 42. That is, the valve body 43 closes the valve holes 42 by rising (see the closed valve state shown in FIG. 1), and opens the valve holes 42 by falling (see the open valve state shown in FIG. 2). The case 41 is provided with an air vent 49 that releases air from the storage chamber 24 to the outflow path 25 via the internal space of the case 41.

[0020] The driver 44 moves the pair of valve bodies 43 up and down according to the drain water level in the reservoir chamber 24. The driver 44 has a hollow float 45, a lever 46, and an operating rod 48.

[0021] The float 45 is formed in a hollow spherical shape, i.e., a spherical shell shape, and is housed in the storage chamber 24. The float 45 is made of metal. The float 45 rises and falls according to the drain water level in the storage chamber 24. The lever 46 is connected to the float 45. The lever 46 is rotatably supported by a shaft 47a provided in the storage chamber 24. The lever 46 swings around the shaft 47a as the float 45 rises and falls.

[0022] The operating rod 48 extends generally in the vertical direction, with one end connected to the lever 46 and the other end connected to the pair of valve bodies 43. More specifically, one end of the operating rod 48 is rotatably connected to a shaft 47b provided on the lever 46. The shaft 47b is provided on the lever 46 on the opposite side of the shaft 47a from the float 45 side. The operating rod 48 moves up and down in accordance with the swing of the lever 46. In other words, the valve mechanism 4 moves the pair of valve bodies 43 up and down as the operating rod 48 moves up and down in accordance with the rise and fall of the float 45.

[0023] In drain trap 100 configured in this manner, when little drain has accumulated in storage chamber 24, float 45 is located near the bottom of storage chamber 24, as shown in Figure 1. In this state, operating rod 48 and valve body 43 are raised, and valve hole 42 is closed by valve body 43. Therefore, even if steam from the steam system flows into storage chamber 24 from inlet channel 21, the steam is prevented from flowing out from storage chamber 24 to outlet channel 25. In this way, drain trap 100 prevents the flowing in steam from flowing out.

[0024] When condensate is generated in the steam system, the condensate flows into and accumulates in the storage chamber 24. As the condensate accumulates in the storage chamber 24, the float 45 rises. When the float 45 rises, the operating rod 48 and valve body 43 descend, opening the valve hole 42. This allows the condensate in the storage chamber 24 to flow out through the outflow path 25. In this way, the condensate trap 100 allows the condensate to flow out while preventing the outflow of steam.

[0025] <Float connection structure> Fig. 3 is a cross-sectional view showing the connection structure of the float 45. Fig. 4 is a plan view showing the float 45 as viewed from the lever 46 side. Fig. 5 is a perspective view showing the mounting member 50 as viewed from the protruding portion 53 side.

[0026] The connecting structure of the float 45 (hereinafter also simply referred to as the connecting structure) is a structure for connecting the lever 46, which is the connecting object, to the float 45. This connecting structure includes the float 45 and the mounting member 50.

[0027] The mounting member 51 is fixed to the float 45 and connected to the lever 46. The mounting member 50 has a base 51, a shaft portion 52, and a plurality of protrusions 53.

[0028] The base 51 is located outside the float 45 and has a contact surface 51a that contacts the outer surface of the float 45. The base 51 is connected to the lever 46, more specifically, connected to the lever 46 via a shaft portion 52. The base 51 is formed in a flat, approximately conical shape. The axis A of the base 51 is coaxial with the axis of the lever 46. The contact surface 51a of the base 51 is a surface that corresponds to the bottom surface of the cone and is formed in a spherical shape that is concave along the outer surface 45c of the float 45.

[0029] The shaft portion 52 is directly connected to the lever 46. Specifically, the shaft portion 52 is provided on the opposite side of the base 51 from the contact surface 51a. The shaft portion 52 is formed integrally with the base 51. The shaft portion 52 is formed in a substantially cylindrical shape coaxial with the axis A. A female thread 52a is formed in the axial direction of the shaft portion 52. The female thread 52a is threadedly engaged with a male thread (not shown) provided on the lever 46. In other words, the shaft portion 52 and the lever 46 are connected by being threadedly engaged with each other.

[0030] The multiple protrusions 53 protrude from the contact surface 51a and penetrate the float 45. In this example, four protrusions 53 are provided. Each of the four protrusions 53 is formed in a substantially cylindrical shape, more specifically, in a substantially cylindrical shape having an axis extending parallel to the axis A. Hereinafter, when it is necessary to distinguish between the four protrusions 53, they will be referred to as a first protrusion 53a, a second protrusion 53b, a third protrusion 53c, and a fourth protrusion 53d.

[0031] 5, the plurality of protrusions 53 include two protrusions 53 that are arranged vertically with the axis A of the base 51 between them. That is, the first protrusion 53a and the second protrusion 53b are arranged vertically with the axis A located between them. The third protrusion 53c and the fourth protrusion 53d are arranged horizontally with the axis A located between them.

[0032] 4, the float 45 is formed with four through holes 45e corresponding to the four protrusions 53. Specifically, each of the four through holes 45e is formed to have approximately the same diameter as the protrusions 53. Each of the four protrusions 53 is inserted into one of the four through holes 45e.

[0033] The connecting structure includes a first weld 61 that welds the base 51 to the outer surface 45c of the float 45, and a plurality of second welds 62 that weld each of the plurality of protrusions 53 to the inner surface 45d of the float 45. In this example, four second welds 62 are provided. That is, the second welds 62 weld the inner side of each of the four protrusions 53 to the inner surface 45d of the float 45. The "inner side of the protrusions 53" refers to the portion of the protrusion 53 that is located inside the float 45. The first weld 61 is an example of an outer weld, and the second weld 62 is an example of an inner weld.

[0034] Specifically, the first welds 61 are provided at corners formed by the outer peripheral surface of the base 51 and the outer surface 45c of the float 45. The first welds 61 are full-circumference fillet welds welded around the entire circumference of the base 51. Each of the four second welds 62 is provided at a corner formed by the outer peripheral surface of the protrusion 53 and the inner surface 45d of the float 45. The second welds 62 are full-circumference fillet welds welded around the entire circumference of the protrusion 53.

[0035] In this way, the mounting member 51 is welded to the float 45 by the first weld 61 and the four second welds 62. As shown in Fig. 3, the float 45 is formed into a hollow spherical shape by welding together two hemispherical shell-shaped segments 45a and 45b.

[0036] Furthermore, the throat thickness of the first welded portion 61 is smaller than the throat thickness of the second welded portion 62. In other words, the weld strength of the first welded portion 61 is smaller than the weld strength of the second welded portion 62. More specifically, the four second welded portions 62 ensure a weld strength that can withstand stresses such as tensile stress, compressive stress, bending stress, and torsional stress that may occur during normal operation. The first welded portion 61 is a seal weld that can prevent fluids such as drainage and steam from entering the four through-holes 45e from between the base 51 and the outer surface 45c of the float 45.

[0037] According to the connection structure configured as above, the joining strength between the float 45 and the mounting member 50 by welding can be improved.

[0038] Specifically, the connecting structure includes a hollow float 45, a base 51 provided on the outside of the float 45 and having a contact surface 51a that contacts the outer surface 45c of the float 45, for connecting to an object to be connected (i.e., the lever 46), an attachment member 50 that protrudes from the contact surface 51a and has a plurality of protrusions 53 that penetrate the float 45, a first welding portion 61 that welds the base 51 to the outer surface 45c of the float 45, and a plurality of second welding portions 62 that weld each of the plurality of protrusions 53 to the inner surface 45d of the float 45.

[0039] According to this configuration, the mounting member 50 is welded to the float 45 by a first weld 61 located on the outside of the float 45 and a second weld 62 located on the inside of the float 45. Because a plurality of second welds 62 are provided, it is easier to ensure the required weld line length for the second welds 62 compared to, for example, when a single second weld is provided. This makes it easier to ensure that the first welds 61 and the second welds 62 have sufficient weld strength to withstand stresses such as tensile stress and compressive stress that may occur during normal operation. This improves the welded joint strength between the float 45 and the mounting member 50. Therefore, it is possible to prevent the mounting member 50 from coming off the float 45 due to damage to the welds.

[0040] Furthermore, this configuration can also suppress damage to the welded portion due to impact force. Generally, a heat-affected zone is generated in a welded portion, where the mechanical properties of the material change due to welding heat. The heat-affected zone has high hardness and low notch toughness (impact value). Normally, the greater the weld strength, the larger the area of ​​the heat-affected zone becomes, and the lower the impact value becomes. A lower impact value makes the material vulnerable to sudden impact forces.

[0041] With this connection structure, when an impact force acts on the storage chamber 24 due to water hammer or the sudden inflow of a large amount of drainage, the impact force does not act on the multiple second welds 62, even though the impact value is low, because they are located inside the float 45. On the other hand, because it is easy to ensure the required weld strength in the second welds 62, the weld strength of the first welds 61 does not need to be as high. Therefore, a decrease in the impact value of the first welds 61 can be suppressed. As a result, the overall impact value of the first welds 61 and the second welds 62 is substantially increased, suppressing damage to the welds (i.e., the first welds 61 and the second welds 62) due to the impact force.

[0042] The base 51 has an axis A that is coaxial with the axis of the lever 46. The plurality of protrusions 53 includes two protrusions 53 that are arranged vertically with the axis A of the base 51 therebetween.

[0043] According to this configuration, the two protrusions 53 (i.e., the first protrusion 53a and the second protrusion 53b) are arranged in the vertical direction, which is the same as the direction in which the lever 46 moves, and further arranged with the axis A, which is coaxial with the axis of the lever 46, between them. Therefore, it is possible to effectively improve the welding strength that can withstand stress that may occur with the movement of the lever 46, i.e., the movement of the float 45.

[0044] Furthermore, the throat thickness of the first welded portion 61 is smaller than the throat thickness of the second welded portion 62 .

[0045] With this configuration, the weld strength of the first weld 61 can be made significantly lower than the weld strength of the second weld 62. Specifically, the second weld 62 is ensured with a weld strength that can withstand stresses such as tensile stress and compressive stress that can occur during normal operation, and the first weld 61 can be seal-welded to prevent fluid from entering the float 45. This significantly reduces the decrease in impact value of the first weld 61, which is provided on the outside of the float 45, i.e., the first weld 61 on which an impact force can act. This further reduces damage to the first weld 61 and the second weld 62 due to impact forces.

[0046] Other Embodiments As described above, the above embodiment has been described as an example of the technology disclosed in this application. However, the technology of the present disclosure is not limited to this and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made as appropriate. Furthermore, the components described in the above embodiment can be combined to create new embodiments. Furthermore, the components described in the accompanying drawings and detailed description may include not only components essential for solving the problem, but also components that are not essential for solving the problem in order to exemplify the technology. Therefore, the fact that these non-essential components are described in the accompanying drawings or detailed description should not be interpreted as immediately determining that these non-essential components are essential.

[0047] For example, the number of protrusions 53 (i.e., the number of second welds 62) is not limited to the above, and may be two, three, five or more. For example, when six protrusions 53 are provided, two of the protrusions are arranged vertically as in the above embodiment, and the remaining four protrusions 53 are arranged two on each side. Basically, the more the number of second welds 62 increases, the greater the overall welding strength of the multiple second welds 62.

[0048] Furthermore, the arrangement of the plurality of protrusions 53 may be any arrangement, and for example, it is not necessary to have two protrusions aligned in the vertical direction with the axis A of the base 51 between them.

[0049] Furthermore, the shape of the protrusion 53 is not limited to the one described above, and may be, for example, a rectangular column or an elliptical column.

[0050] The throat thickness of the first welded portion 61 may be approximately the same as the throat thickness of the second welded portion 62.

[0051] The shape of the float 45 may be an oval sphere or a rectangle, other than a sphere.

[0052] The float connection structure of the present disclosure may also be applied to devices other than the aforementioned drain trap 100. For example, this connection structure may also be applied to a liquid pumping device that pumps drain stored in a storage chamber to the outside by introducing steam. [Industrial Applicability]

[0053] As described above, the technology of the present disclosure is useful for a connecting structure of floats. [Explanation of symbols]

[0054] 45 Float 45c outer surface 45d inner surface 46 Lever (connected object) 50 Mounting material 51 Base 51a Contact surface 53 Protrusion 61 First weld (outer weld) 62 Second weld (inner weld) A axis center

Claims

1. A hollow float and a base provided on the outside of the float and having a contact surface in contact with the outer surface of the float, for connecting to an object to be connected; and a mounting member having a plurality of protrusions protruding from the contact surface and penetrating the float; an outer weld that welds the base to the outer surface of the float; a plurality of inner welds that weld each of the plurality of protrusions to the inner surface of the float; A float connection structure characterized by the above.

2. 2. The float connection structure according to claim 1, the base has an axis that is coaxial with an axis of the object to be connected, The plurality of protrusions include two protrusions arranged vertically with the axis of the base therebetween. A float connection structure characterized by the above.

3. The float connection structure according to claim 1 or 2, The throat thickness of the outer weld is smaller than the throat thickness of the inner weld. A float connection structure characterized by the above.

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