Portable tree diameter measuring device

Abstract

The invention relates to the technical field of measuring devices, and discloses a portable tree diameter measuring device which comprises a measuring tape shell, a wind-up roller measuring cloth strip and a rotating handle, the other end of the measuring cloth strip penetrates through the measuring tape shell, one side of the outer wall of the measuring tape shell is fixedly connected with a side plate, and the other side of the side plate is fixedly connected with a liquid storage tank. A liquid storage cavity is formed in the liquid storage box, a liquid conveying mechanism is connected to the bottom face of the liquid storage cavity, an extraction assembly and a conveying assembly are connected to the other end of the liquid conveying mechanism, the other end of the conveying assembly penetrates through the liquid storage box and is connected with two symmetrically-arranged supporting blocks, and cleaning cotton is connected to the adjacent sides of the two supporting blocks. The two pieces of cleaning cotton are located on the two sides of the measuring cloth strip respectively. According to the portable tree diameter measuring device, after a user measures the diameter of a tree through the measuring tape shell measuring cloth strip, the surface of the measuring cloth strip can be wiped and cleaned through the two pieces of cleaning cotton when the measuring cloth strip is recycled, and then the probability that the measuring cloth strip is damaged is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of measuring devices, in particular to a portable tree diameter measuring device. BACKGROUND

[0002] The measurement of tree diameter is very important in the fields of forestry, ecology, environmental science, and urban greening management. By measuring the diameter of trees, a lot of information about forest resources, ecological health, and environmental conditions can be obtained.

[0003] The patent with the publication number CN220541927U discloses a portable tree diameter measuring device. The device includes a measuring tape box, a rubber finger sleeve fixedly installed on one side surface of the measuring tape box, an expansion hole opened above the rubber finger sleeve on the one side surface of the measuring tape box, and a cleaning structure fixedly installed on the one side surface of the measuring tape box at the port position of the expansion hole. The device can prevent the measuring device from falling off and being damaged during measurement, quickly position and read the data, calculate the diameter of the tree according to the value of pi, and avoid greater measurement errors. The device can also scrape off water stains and debris on the surface of the measuring tape, prevent water stains from being brought into the measuring tape box during rainy days, and affect the use of the internal vortex spring and other metal parts. Thus, the device can better play a protective role.

[0004] However, the current tree diameter measuring device still has the following problems in actual use: Trees are located outdoors all year round, and their surfaces will inevitably be attached with resin, dust, soil, moss, and other substances. When the tape (mostly cloth tape) measures the diameter of the tree trunk, these substances will adhere to the tape, which not only affects the normal reading and accuracy of the tape, but also may reduce the service life of the tape. SUMMARY

[0005] To overcome the shortcomings of the prior art, the present application provides a portable tree diameter measuring device. After the user measures the diameter of the tree with the measuring cloth outside the tape housing, the surface of the measuring cloth can be wiped and cleaned by the two cleaning cottons when the measuring cloth is recycled, thereby reducing the probability of damage to the measuring cloth.

[0006] In order to achieve the above object, the present application provides the following technical scheme: A portable tree diameter measuring device, comprising a tape housing, a winding roller installed inside the tape housing, a measuring cloth strip installed on the surface of the winding roller, and a rotating handle installed at one end outside the winding roller, the other end of the measuring cloth strip penetrates the tape housing, one side of the outer wall of the tape housing is fixedly connected with a side plate, the other side of the side plate is fixedly connected with a liquid storage tank, a liquid storage cavity is formed in the inside of the liquid storage tank, a liquid delivery mechanism is connected to the bottom surface of the liquid storage cavity, the other end of the liquid delivery mechanism is connected with a drawing assembly and a delivery assembly, the other end of the delivery assembly penetrates the liquid storage tank and is connected with two symmetrically arranged supporting blocks, the adjacent sides of the two supporting blocks are both connected with cleaning cotton, the two cleaning cottons are respectively located on the two sides of the measuring cloth strip, the two supporting blocks are both connected with the tape housing, the outer wall of the upper end of the liquid storage tank is fixedly connected with a liquid adding pipe, the outer wall of the liquid adding pipe is threadedly connected with a sealing cover, and the liquid adding pipe is in communication with the liquid storage cavity.

[0007] Further, the liquid delivery mechanism comprises a supporting pipe, a push rod, a piston and a pull knob, the outer wall of the supporting pipe is fixedly connected with the inner wall of the liquid storage tank, a drawing cavity is formed in the inside of the supporting pipe, the outer wall of the piston is slidably connected with the inner wall of the drawing cavity, the bottom surface of the piston is fixedly connected with one end of the push rod, the other end of the push rod penetrates the supporting pipe and is fixedly connected with one end of the pull knob, the drawing assembly and the delivery assembly are both connected with the upper end of the supporting pipe, and the piston is located below the drawing assembly and the delivery assembly.

[0008] Further, the delivery assembly comprises a liquid delivery pipe and a shunt pipe, one end of the liquid delivery pipe is fixedly connected with the upper end of the supporting pipe, the other end of the liquid delivery pipe is fixedly connected with one end of the shunt pipe, the other two ends of the shunt pipe are respectively connected with the outer walls of the two supporting blocks, and the inner wall of the end of the liquid delivery pipe close to the supporting pipe is provided with a one-way valve.

[0009] Further, one side of each of the two supporting blocks is provided with a threaded hole, the outer walls of the other two ends of the shunt pipe are respectively threadedly connected with the inner walls of the two threaded holes, the inside of the drawing cavity, the liquid delivery pipe, the shunt pipe and the threaded hole are in communication, and the two supporting blocks are hingedly connected with the tape housing.

[0010] Further, the drawing assembly comprises a counterweight ball and a liquid suction pipe, one end of the liquid suction pipe is fixedly connected with the side wall of the upper end of the supporting pipe, the other end of the liquid suction pipe is fixedly connected with the outer wall of the counterweight ball, a plurality of liquid suction holes are formed in the outer wall of the counterweight ball, the inside of the drawing cavity, the liquid suction pipe and the plurality of liquid suction holes are in communication, and the inner wall of the end of the liquid suction pipe close to the supporting pipe is provided with a one-way valve.

[0011] Further, the adjacent sides of the two supporting blocks are both provided with sliding openings, the inner walls of the two sliding openings are respectively matched with and slidably connected with the two sides of the outer wall of the measuring cloth strip.

[0012] Further, the end of the measuring cloth strip penetrating the sliding opening is fixedly connected with a U-shaped block, the inner wall of the other end of the U-shaped block is rotatably connected with a rotating block, and the inner wall of the rotating block penetrates and is threadedly connected with a plurality of tapered rods.

[0013] Further, the inner wall of the U-shaped block is fixedly connected with a magnetic attraction plate, and the magnetic attraction plate is attracted to the outer wall of the rotating block.

[0014] Further, the end of the measuring cloth strip penetrating the sliding opening is fixedly connected with a U-shaped block, the inner wall of the other end of the U-shaped block is rotatably connected with a rotating block, and the inner wall of the rotating block penetrates and is threadedly connected with a plurality of tapered rods.

[0015] Further, the outer wall of the liquid storage tank penetrates and is provided with an observation hole, the inner wall of the observation hole is provided with a transparent glass, and one side of the observation hole is provided with a scale line.

[0016] Compared with the prior art, the present application has the following beneficial effects: The portable tree diameter measuring device is provided with a liquid storage tank and two supporting blocks outside the tape housing, a liquid delivery mechanism, an extraction assembly and a delivery assembly inside the liquid storage tank, and cleaning cotton inside the two supporting blocks. After the user measures the diameter of the tree by the measuring cloth strip of the tape housing, the surface of the measuring cloth strip can be wiped and cleaned by the two cleaning cottons when the measuring cloth strip is recycled, thereby reducing the probability of damage to the measuring cloth strip. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall appearance of the present application; Figure 2 It is a schematic diagram of the overall appearance of the present application from another perspective; Figure 3 It is a schematic diagram of the internal structure of the tape housing in the present application; Figure 4 It is a detailed connection diagram of the tape housing, the measuring cloth strip and the U-shaped block and other components in the present application; Figure 5 It is a detailed connection diagram of the liquid storage tank, the liquid delivery mechanism and the supporting block and other components in the present application; Figure 6 It is a detailed connection diagram of the liquid storage tank, the liquid delivery mechanism and the supporting block and other components in the present application; Figure 5 It is an enlarged schematic diagram of position A in the present application; Figure 7 It is a detailed connection diagram of the liquid delivery mechanism, the extraction assembly and the delivery assembly in the present application; Figure 8 It is a detailed connection diagram of the supporting block, the cleaning cotton and the plug and other components in the present application.

[0018] In the figure: 1, tape housing; 2, side plate; 3, liquid storage tank; 4, sealing cover; 5, pull knob; 6, viewing port; 7, scale; 8, support block; 9, infusion tube; 10, shunt tube; 11, handle; 12, winding roller; 13, U-shaped block; 14, rotating block; 15, tapered rod; 16, measuring cloth strip; 17, magnetic plate; 18, sliding port; 19, liquid storage cavity; 20, support tube; 21, liquid filling tube; 22, counterweight ball; 23, liquid suction hole; 24, liquid suction tube; 25, push rod; 26, piston; 27, extraction cavity; 28, plug; 29, jack; 30, cleaning cotton; 31, threaded hole. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all.

[0020] Please refer to Figures 1-8 A portable tree diameter measuring device, comprising a tape housing 1, a winding roller 12 installed inside the tape housing 1, a measuring cloth strip 16 installed on the surface of the winding roller 12, and a handle 11 installed on one end of the winding roller 12 outside, the other end of the measuring cloth strip 16 penetrates the tape housing 1, one side of the outer wall of the tape housing 1 is fixedly connected with a side plate 2, the other side of the side plate 2 is fixedly connected with a liquid storage tank 3, the inside of the liquid storage tank 3 is provided with a liquid storage cavity 19, the bottom surface of the liquid storage cavity 19 is connected with an infusion mechanism, the other end of the infusion mechanism is connected with an extraction assembly and a delivery assembly, the other end of the delivery assembly penetrates the liquid storage tank 3 and is connected with two symmetrically arranged support blocks 8, one side of each of the two support blocks 8 is connected with a cleaning cotton 30, the two cleaning cottons 30 are respectively located on both sides of the measuring cloth strip 16, the two support blocks 8 are connected with the tape housing 1, the outer wall of the upper end of the liquid storage tank 3 is fixedly connected with a liquid filling tube 21, the outer wall of the liquid filling tube 21 is threadedly connected with a sealing cover 4, and the liquid filling tube 21 communicates with the liquid storage cavity 19.

[0021] The portable tree diameter measuring device in the present application is similar in structure to the existing portable tree diameter measuring device, such as the portable tree diameter measuring device disclosed in the patent with publication number CN220541927U. Figures 1-8As shown, the portable tree diameter measuring device in the application measures the diameter of the tree first. The measuring personnel rotates the handle 11 to release a suitable length of the measuring tape 16 from the outside of the winding roller 12 and the inside of the tape housing 1, then wraps the released measuring tape 16 around the tree to be measured (the current conventional measuring height is 1.3-1.5 meters from the ground, and the specific height is not limited), then observes the reading displayed on the measuring tape 16, and then the diameter can be measured by the circumference (the current commonly used is that the circumference is approximately equal to the diameter, the formula is: C / π=D, of course, some measuring tapes 16 have length and diameter readings, at this time the diameter length can be directly read out).

[0022] After the diameter of the tree is tested, the measuring tape 16 needs to be recovered. Before recovery, the tester only needs to manually press the infusion mechanism, and the infusion mechanism can extract the cleaning liquid from the inside of the liquid storage cavity 19 of the liquid storage tank 3 through the extraction assembly and deliver it to the two cleaning cottons 30 inside the two supporting blocks 8. At this time, rotating the handle 11 can wind the measuring tape 16 into the inside of the tape housing 1 through the winding roller 12. During the recovery of the measuring tape 16, the two sides of the measuring tape 16 will contact the two cleaning cottons 30 on both sides, so that the surface of the measuring tape 16 can be wiped off the resin, dust, soil, moss and other substances adhered to the surface while passing through, thereby reducing the probability of damage to the measuring tape 16.

[0023] As a preferred embodiment of the application, the infusion mechanism comprises a supporting pipe 20, a push rod 25, a piston 26 and a pull knob 5. The outer wall of the supporting pipe 20 is fixedly connected with the inner wall of the liquid storage tank 3. The inside of the supporting pipe 20 is provided with an extraction cavity 27. The outer wall of the piston 26 is slidably connected with the inner wall of the extraction cavity 27. The bottom surface of the piston 26 is fixedly connected with one end of the push rod 25. The other end of the push rod 25 penetrates through the supporting pipe 20 and is fixedly connected with one end of the pull knob 5. The extraction assembly and the delivery assembly are both connected with the upper end of the supporting pipe 20. The piston 26 is located below the extraction assembly and the delivery assembly.

[0024] More specifically, when it is necessary to deliver cleaning liquid to the two cleaning cottons 30, the pull knob 5 is first pulled. After the pull knob 5 is stressed, it pulls the piston 26 down in the extraction cavity 27 through the push rod 25. At the same time, the extraction assembly at the upper end of the supporting pipe 20 has a smaller internal pressure, so that the cleaning liquid is extracted from the inside of the liquid storage cavity 19. Then the pull knob 5 is pressed again. After the pull knob 5 moves upward, it pushes the piston 26 upward, so that the cleaning liquid extracted into the extraction cavity 27 before can be pushed into the delivery assembly. Then the cleaning liquid is delivered into the two cleaning cottons 30 through the delivery assembly, so that the surface of the passing measuring tape 16 can be wiped and cleaned.

[0025] As a preferred scheme of the present application, the conveying assembly comprises the infusion tube 9 and the shunt tube 10, one end of the infusion tube 9 is fixedly connected with the upper end of the supporting tube 20, the other end of the infusion tube 9 is fixedly connected with one end of the shunt tube 10, the other two ends of the shunt tube 10 are respectively connected with the outer walls of the two supporting blocks 8, and the inner wall of the end of the infusion tube 9 close to the supporting tube 20 is provided with the one-way valve.

[0026] More specifically, when the piston 26 moves upward, the cleaning liquid in the extraction cavity 27 is pushed into the infusion tube 9, and then is shunted into the two cleaning cottons 30 in the two supporting blocks 8 through the shunt tube 10, so that the surface of the measuring cloth strip 16 can be cleaned by the two cleaning cottons 30.

[0027] As a preferred scheme of the present application, the two supporting blocks 8 are respectively provided with the threaded holes 31 on one side, the other two ends of the shunt tube 10 are respectively threadedly connected with the inner walls of the two threaded holes 31, the extraction cavity 27, the infusion tube 9, the shunt tube 10 and the threaded holes 31 are internally communicated, and the two supporting blocks 8 are respectively hingedly connected with the tape housing 1.

[0028] More specifically, by arranging the threaded holes 31, the shunt tube 10 far from the infusion tube 9 can be more conveniently detached from the supporting blocks 8 when it needs to be cleaned and replaced.

[0029] As a preferred scheme of the present application, the extraction assembly comprises the counterweight ball 22 and the suction tube 24, one end of the suction tube 24 is fixedly connected with the side wall of the upper end of the supporting tube 20, the other end of the suction tube 24 is fixedly connected with the outer wall of the counterweight ball 22, the outer wall of the counterweight ball 22 is provided with the suction holes 23, the extraction cavity 27, the suction tube 24 and the suction holes 23 are internally communicated, and the inner wall of the end of the suction tube 24 close to the supporting tube 20 is provided with the one-way valve.

[0030] More specifically, when the piston 26 moves downward, the pressure in the extraction cavity 27 is reduced, so that the suction holes 23 of the counterweight ball 22 in the liquid storage cavity 19 can send the cleaning liquid to the extraction cavity 27 through the suction tube 24.

[0031] It should be particularly noted that because the one-way valves are arranged in the suction tube 24 and the infusion tube 9, and the one-way valve of the suction tube 24 can only enter, and the one-way valve of the infusion tube 9 can only exit, the cleaning liquid in the liquid storage cavity 19 can be extracted and output from the infusion tube 9.

[0032] As a preferred scheme of the present application, the two supporting blocks 8 are respectively provided with the sliding openings 18 on the adjacent sides, and the inner walls of the two sliding openings 18 are respectively matched with and slidably connected with the two sides of the outer wall of the measuring cloth strip 16.

[0033] More specifically, by setting the sliding opening 18, the measuring cloth 16 can be wrapped inside, avoiding the measuring cloth 16 from falling off the side of the support block 8, thereby affecting the cleaning effect.

[0034] As a preferred scheme of the present application, the measuring cloth 16 is fixedly connected with the U-shaped block 13 at one end penetrating the sliding opening 18, the other end of the U-shaped block 13 is rotatably connected with the rotating block 14, and the rotating block 14 is penetrated and threadedly connected with the plurality of tapered rods 15.

[0035] More specifically, some trees are thicker, and a detector may not be able to successfully embrace, and at this time, a length of the measuring cloth 16 needs to be reserved, and the detector places the measuring cloth 16 or the tape housing 1 on the ground, and then moves around the tree with the other end, and then aligns the two ends to detect the tree, but because the reserved length is usually greater than the diameter of the tree, the measuring cloth 16 may be in an inclined state after being connected with the tape housing 1, and because the tree is thicker, the detector is also not convenient to adjust the height, which is very inconvenient.

[0036] At this time, by setting the U-shaped block 13, the rotating block 14 and the tapered rod 15, the outer end of the measuring cloth 16 can be drilled into the tree through the tapered rod 15 before measuring the tree, which can limit the detection height, and then the detector reads the value after aligning the two ends after moving around the tree, which is convenient and fast.

[0037] As a preferred scheme of the present application, the inner wall of the U-shaped block 13 is fixedly connected with the magnetic plate 17, and the magnetic plate 17 is attracted to the outer wall of the rotating block 14.

[0038] More specifically, by setting the magnetic plate 17, the rotating block 14 can be attracted to the magnetic plate 17 when the tapered rod 15 is not needed, which is convenient for storage and does not occupy too much external space.

[0039] As a preferred scheme of the present application, the two sides of the end of one support block 8 away from the tape housing 1 are fixedly connected with a plurality of plugs 28, the two sides of the end of the other support block 8 away from the tape housing 1 are provided with a plurality of insertion holes 29, and the outer walls of the plurality of plugs 28 are respectively connected with the inner walls of the plurality of insertion holes 29.

[0040] More specifically, after the cleaning cotton 30 cleans the measuring cloth 16 for a period of time, the two support blocks 8 are expanded to the two sides, and then the cleaning cotton 30 between the two support blocks 8 is replaced. By setting the plug 28 and the insertion hole 29, the end of the two support blocks 8 away from the tape housing 1 can be fixed, avoiding the separation of the two support blocks 8 when the cleaning cotton 30 does not need to be replaced.

[0041] As a preferred scheme of the present application, the outer wall of the liquid storage tank 3 is provided with an observation opening 6, the inner wall of the observation opening 6 is provided with transparent glass, and the observation opening 6 is provided with scale lines 7 on one side.

[0042] More specifically, by providing the observation opening 6 and the scale lines 7, the capacity of the cleaning liquid inside the liquid storage tank 3 can be intuitively understood.

[0043] Although the embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and alterations can be made thereto without departing from the principles and spirit of the present application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A portable tree diameter measuring device comprising a tape housing (1), a winding roller (12) installed inside the tape housing (1), a measuring tape (16) installed on the surface of the winding roller (12), and a handle (11) installed on one end of the outside of the winding roller (12), the other end of the measuring tape (16) penetrating the tape housing (1), characterized in that: The side of the outer wall of the tape housing (1) is fixedly connected with a side plate (2), the other side of the side plate (2) is fixedly connected with a liquid storage tank (3), the inside of the liquid storage tank (3) is provided with a liquid storage cavity (19), the bottom surface of the liquid storage cavity (19) is connected with a liquid delivery mechanism, the other end of the liquid delivery mechanism is connected with a drawing assembly and a conveying assembly, the other end of the conveying assembly penetrates through the liquid storage tank (3) and is connected with two symmetrically arranged supporting blocks (8), the adjacent sides of the two supporting blocks (8) are both connected with cleaning cotton (30), the two cleaning cotton (30) are respectively located on the two sides of the measuring cloth strip (16), the two supporting blocks (8) are both connected with the tape housing (1), the outer wall of the upper end of the liquid storage tank (3) is fixedly connected with a liquid adding pipe (21), the outer wall of the liquid adding pipe (21) is threadedly connected with a sealing cover (4), and the liquid adding pipe (21) is in communication with the liquid storage cavity (19).

2. A portable tree diameter measuring device according to claim 1, wherein: The liquid delivery mechanism comprises a supporting pipe (20), a push rod (25), a piston (26) and a pull knob (5), the outer wall of the supporting pipe (20) is fixedly connected with the inner wall of the liquid storage tank (3), the inside of the supporting pipe (20) is provided with a drawing cavity (27), the outer wall of the piston (26) is slidably connected with the inner wall of the drawing cavity (27), the bottom surface of the piston (26) is fixedly connected with one end of the push rod (25), the other end of the push rod (25) penetrates through the supporting pipe (20) and is fixedly connected with one end of the pull knob (5), and the drawing assembly and the conveying assembly are both connected with the upper end of the supporting pipe (20), and the piston (26) is located below the drawing assembly and the conveying assembly.

3. A portable tree diameter measuring device according to claim 2, wherein: The conveying assembly comprises a liquid delivery pipe (9) and a shunt pipe (10), one end of the liquid delivery pipe (9) is fixedly connected with the upper end of the supporting pipe (20), the other end of the liquid delivery pipe (9) is fixedly connected with one end of the shunt pipe (10), the other two ends of the shunt pipe (10) are respectively connected with the outer walls of the two supporting blocks (8), and the inner wall of one end of the liquid delivery pipe (9) close to the supporting pipe (20) is provided with a one-way valve.

4. A portable tree diameter measuring device according to claim 3, wherein: The other two ends of the shunt pipe (10) are respectively connected with the inner walls of the two threaded holes (31), the inside of the drawing cavity (27), the liquid delivery pipe (9), the shunt pipe (10) and the threaded hole (31) are in communication, and the two supporting blocks (8) are both hingedly connected with the tape housing (1).

5. A portable tree diameter measuring device according to claim 3 or 4, characterised in that: The drawing assembly comprises a counterweight ball (22) and a liquid suction pipe (24), one end of the liquid suction pipe (24) is fixedly connected with the side wall of the upper end of the supporting pipe (20), the other end of the liquid suction pipe (24) is fixedly connected with the outer wall of the counterweight ball (22), the outer wall of the counterweight ball (22) is provided with a plurality of liquid suction holes (23), the inside of the drawing cavity (27), the liquid suction pipe (24) and the plurality of liquid suction holes (23) are in communication, and the inner wall of one end of the liquid suction pipe (24) close to the supporting pipe (20) is provided with a one-way valve.

6. A portable tree diameter measuring device according to claim 1, 2, 3 or 4, wherein: The adjacent sides of the two supporting blocks (8) are both provided with sliding openings (18), and the inner walls of the two sliding openings (18) are respectively matched with and slidably connected with the two sides of the outer wall of the measuring cloth strip (16).

7. A portable tree diameter measuring device according to claim 6, wherein: The measuring cloth strip (16) is fixedly connected with a U-shaped block (13) at one end penetrating a sliding port (18), the other end inner wall of the U-shaped block (13) is rotatably connected with a rotating block (14), the inner wall of the rotating block (14) penetrates and is screw-connected with a plurality of conical rods (15).

8. A portable tree diameter measuring device according to claim 7, wherein: The inner wall of the U-shaped block (13) is fixedly connected with a magnetic attraction plate (17), and the outer wall of the magnetic attraction plate (17) is attracted to the rotating block (14).

9. A portable tree diameter measuring device according to claim 1, 2, 3, 4, 7 or 8, wherein: The other support block (8) is fixedly connected with a plurality of plug-in holes (29) on the two sides of the one end away from the tape housing (1), and the outer wall of the plurality of plug-in holes (29) is respectively connected with the inner wall of the plurality of plug-in holes (29).

10. A portable tree diameter measuring device according to claim 1, 2, 3, 4, 7 or 8, wherein: The outer wall of the liquid storage tank (3) penetrates and is provided with an observation port (6), the inner wall of the observation port (6) is provided with a transparent glass, and the observation port (6) is provided with a scale line (7) on one side.

Images