Manual perimeter measuring device for rectangular sealing ring

Abstract

The utility model provides a manual perimeter measuring device for a rectangular sealing ring, which is characterized in that four quarter-cylinder measuring pieces are arranged on a base in a rectangular shape, the left upper quarter-cylinder measuring piece is fixedly arranged on the base, two axial cut surfaces of the left upper quarter-cylinder measuring piece are respectively and vertically provided with an adjusting rod, the adjusting rods are provided with scale marks, and the scale marks are arranged on the left upper quarter-cylinder measuring piece and the right upper quarter-cylinder measuring piece. The two adjusting rods movably penetrate through one axial cut-off surface of the left lower quarter-cylinder measuring piece and one axial cut-off surface of the right upper quarter-cylinder measuring piece respectively; and the other axial cut-off surfaces of the left lower quarter-cylinder measuring piece and the right upper quarter-cylinder measuring piece are also vertically provided with adjusting rods respectively, and the two adjusting rods movably penetrate through the axial cut-off surface of the right lower quarter-cylinder measuring piece respectively. The device is simple in structure, convenient to use and low in cost; the left lower quarter cylinder measuring piece, the right upper quarter cylinder measuring piece and the right lower quarter cylinder measuring piece can move to adapt to rectangular sealing rings with different length-width ratios, so that the measuring device is universal, and the practicability of the measuring device is improved.

Description

Technical Field

[0001] This utility model relates to the field of rubber rectangular sealing ring measurement technology, specifically, it demonstrates a manual perimeter measuring device for rectangular sealing rings. Background Technology

[0002] Rubber rectangular sealing rings are widely used in various fields of modern industry. The sealing rings are original accessories or parts that prevent liquid or solid particles from leaking between adjacent fusion surfaces and prevent external residues such as dust and water from entering mechanical equipment parts.

[0003] A rectangular O-ring is a ring with a rectangular planar shape and all four corners are rounded. Currently, the inner circumference of rubber rectangular O-rings is mostly measured using vernier calipers. However, because rubber is elastic and closed-loop, the deformation of the four sides cannot be guaranteed to be consistent during measurement. Moreover, vernier calipers cannot accurately measure the length of the four rounded corners of the rectangular O-ring, thus failing to obtain its inner circumference. If estimated manually, the error will increase significantly. Utility Model Content

[0004] The purpose of this invention is to provide a manual circumference measuring device for rectangular sealing rings, which has a simple and practical structure and good performance.

[0005] The technical solution is as follows:

[0006] A manual perimeter measuring device for a rectangular sealing ring is provided, which has four quarter-cylindrical measuring parts set on a base. The four quarter-cylindrical measuring parts are erected at the four corners of the rectangle and are always symmetrical about the center line of the rectangle. When the four quarter-cylindrical measuring parts are completely closed towards the center of the rectangle, they are cylindrical.

[0007] The upper left quarter-cylindrical measuring piece is fixed to the base, and an adjusting rod is vertically installed on each of its two axial cut surfaces. The two adjusting rods respectively move through one axial cut surface of the lower left quarter-cylindrical measuring piece and the upper right quarter-cylindrical measuring piece.

[0008] The remaining three quarter-cylindrical measuring parts all slide relative to the base;

[0009] The lower left quarter-cylindrical measuring piece and the upper right quarter-cylindrical measuring piece are also vertically equipped with adjusting rods on their other axial cut surfaces. These two adjusting rods are staggered vertically and move through the axial cut surface of the lower right quarter-cylindrical measuring piece.

[0010] The two adjusting rods on the upper left quarter-cylindrical measuring piece have scale lines.

[0011] Optionally, the base surface is embedded with two guide rails, the arrangement of which is perpendicular to the two axial cut surfaces of the upper left quarter-cylindrical measuring component. The lower left quarter-cylindrical measuring component and the upper right quarter-cylindrical measuring component are slidably mounted on the guide rails via sliding bodies. The sliding engagement between the sliding bodies and the guide rails ensures smooth movement of the lower left quarter-cylindrical measuring component and the upper right quarter-cylindrical measuring component, allowing them to move smoothly along a predetermined straight line.

[0012] The four quarter-cylindrical measuring elements on the base are all at the same height. This ensures that the adjusting rod positioned between two adjacent quarter-cylindrical measuring elements remains horizontal at all times.

[0013] Optionally, each of the quarter-cylindrical measuring pieces has a protrusion on its outer convex arc surface, with all four protrusions on the same plane. When the rectangular sealing ring is fitted onto these four quarter-cylindrical measuring pieces, the protrusion design restricts the position of the corners of the rectangular sealing ring on the outer convex arc surface of the quarter-cylindrical measuring piece, placing the rectangular sealing ring on a horizontal base surface, which facilitates a more accurate reading of the straight side length of the rectangular sealing ring.

[0014] Optionally, the adjusting rod is cylindrical, with shaft holes provided on the lower left quarter-cylindrical measuring parts, the upper right quarter-cylindrical measuring parts, and the lower right quarter-cylindrical measuring parts for the adjusting rod to be inserted movably. The cylindrical shape of the adjusting rod has the characteristics of symmetry and isotropy, which makes it more stable when it slides relative to the quarter-cylindrical measuring parts, and the quarter-cylindrical measuring parts move more smoothly.

[0015] Optionally, on the upper left quarter-cylindrical measuring piece: the zero mark of the scale line on the adjusting rod is aligned with the axial cut surface of the upper left quarter-cylindrical measuring piece. This ensures that the starting point of the measurement is accurate, thus avoiding measurement errors caused by an inaccurate starting point. It also makes the measurement process more intuitive and convenient, reducing adjustment and calibration steps during measurement.

[0016] Optionally, the two adjusting rods on the upper left quarter-cylindrical measuring piece are on the same plane, and the height of the two adjusting rods on the upper left quarter-cylindrical measuring piece is higher than the height of the adjusting rods on the lower left quarter-cylindrical measuring piece and the upper right quarter-cylindrical measuring piece. This ensures that these four adjusting rods do not interfere with each other and do not affect the displacement of the quarter-cylindrical measuring piece.

[0017] Optionally, handles are provided on both sides of the base to facilitate the movement of the device by workers.

[0018] Compared with existing technologies, the advantages of this invention are as follows: The rectangular sealing ring is fully unfolded using four quarter-cylindrical measuring elements. The arc-shaped corners of the rectangular sealing ring are located on the convex arc surfaces of the quarter-cylindrical measuring elements, keeping the rectangular sealing ring at its natural length. The lengths of the long and wide sides of the rectangular sealing ring can be read from the scale lines of the two adjusting rods on the upper left quarter-cylindrical measuring element. The inner length of the arc-shaped corners on the rectangular sealing ring is the arc length of the convex arc surface on the quarter-cylindrical measuring element. Thus, the inner circumference of the rectangular sealing ring can be calculated. This invention has a simple structure, is easy to use, and is low in cost. The lower left, upper right, and lower right quarter-cylindrical measuring elements are movable to accommodate rectangular sealing rings with different aspect ratios, making the measuring device more versatile and improving its practicality. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a manual perimeter measuring device for a rectangular sealing ring according to an embodiment of this utility model;

[0020] Figure 2 This is a top view schematic diagram of a manual perimeter measuring device for a rectangular sealing ring according to an embodiment of the present invention;

[0021] Figure 3 A schematic diagram for measuring the inner circumference of a rectangular sealing ring;

[0022] The relevant markings in the attached diagram are: 1-base, 2-quarter-cylindrical measuring piece, 3-adjusting rod, 4-guide rail, 5-protrusion, 6-handle, 21-shaft hole, 31-scale line, 41-slider. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] This utility model provides a manual circumference measuring device for rectangular sealing rings, which solves the technical problems mentioned in the background art. For example... Figure 1 and Figure 2As shown, specifically, it includes a horizontally placed base 1, on the top surface of which are distributed four identical quarter-cylindrical measuring parts 2. These four quarter-cylindrical measuring parts 2 are erected at the four corners of a rectangle and are distributed in a rectangular pattern. They are always symmetrical about the center line of the rectangle, either vertically or horizontally. The convex arc surfaces of the quarter-cylindrical measuring parts 2 all face outward. When the four quarter-cylindrical measuring parts are completely closed towards the center of the rectangle, they can form a complete cylinder.

[0025] Among them, the upper left quarter-cylindrical measuring piece 2a is fixed on the base 1, and adjusting rods 3 are vertically fixed on its two axial cut surfaces. The adjusting rods 3 are always in a horizontal position. The two adjusting rods 3 respectively move through one axial cut surface of the lower left quarter-cylindrical measuring piece 2b and the upper right quarter-cylindrical measuring piece 2c. That is to say, the movement direction of the lower left quarter-cylindrical measuring piece 2b is along the width direction of the rectangle, and the movement direction of the upper right quarter-cylindrical measuring piece 2c is along the length direction of the rectangle.

[0026] The other three quarter-cylindrical measuring parts can slide relative to the base; they are movable.

[0027] The lower left quarter-cylindrical measuring piece 2b and the upper right quarter-cylindrical measuring piece 2c each have a horizontal adjusting rod 3 fixed vertically on their other axial cut surfaces. These two adjusting rods are staggered vertically, and they movably pass through the axial cut surface of the lower right quarter-cylindrical measuring piece 2d. In other words, these four quarter-cylindrical measuring pieces and the four adjusting rods can form a shape that fits the inner ring of the rectangular sealing ring, so that the rectangular sealing ring can be fitted onto these four quarter-cylindrical measuring pieces.

[0028] Among them, the two adjusting rods 3 on the upper left quarter-cylindrical measuring piece 2a have scale lines 31 along their length direction to distinguish the length dimensions. The scale lines 31 have scale numbers for marking. One adjusting rod is used to read the distance between the upper left quarter-cylindrical measuring piece 2a and the lower left quarter-cylindrical measuring piece 2b, which represents the straight width length of the rectangular sealing ring. The other adjusting rod is used to read the distance between the upper left quarter-cylindrical measuring piece 2a and the upper right quarter-cylindrical measuring piece 2c, which represents the straight long side length of the rectangular sealing ring.

[0029] During measurement: First, bring one of the curved corners of the rectangular sealing ring into contact with the convex curved surface of the upper left quarter-cylindrical measuring piece 2a to position one apex of the rectangular sealing ring. Next, simultaneously move the lower left quarter-cylindrical measuring pieces 2b and 2c until the convex curved surface of the lower left quarter-cylindrical measuring piece 2b just contacts the other curved corner of the rectangular sealing ring. At this point, one wide side of the rectangular sealing ring is in a naturally extended state. Then, simultaneously move the upper right quarter-cylindrical measuring pieces 2c and 2d until the convex curved surfaces of the upper right quarter-cylindrical measuring pieces 2c and 2d just contact the remaining two curved corners of the rectangular sealing ring. At this point, the rectangular sealing ring is in a naturally extended state, exhibiting a rectangular shape, and is not overstretched. Finally, read the lengths of the long and wide sides of the rectangular sealing ring through the scale lines 31 of the two adjusting rods 3 on the upper left quarter-cylindrical measuring piece 2a, and record them as A and B.

[0030] The radius of the quarter-cylindrical measuring piece is known, denoted as R. The total inner length of the four arc-shaped corners of the rectangular sealing ring can be considered as the circumference of a complete cylindrical measuring piece, which can be referenced... Figure 3 As shown, the inner circumference of the entire rectangular sealing ring is approximately estimated to be 2(A+B)+2πR.

[0031] In this embodiment, two guide rails 4 are embedded on the surface of the base 1. The arrangement direction of the two guide rails 4 is perpendicular to the two axial cut surfaces of the upper left quarter-cylindrical measuring piece 2a. The lower left quarter-cylindrical measuring piece 2b and the upper right quarter-cylindrical measuring piece 2c are slidably mounted on the guide rails 4 via sliders 41, so that the lower left quarter-cylindrical measuring piece 2b slides along the width direction of the rectangle, and the upper right quarter-cylindrical measuring piece 2c slides along the length direction of the rectangle. The guide rails are embedded in the base, while the sliders are movably connected to the guide rails in a snap-fit ​​manner, i.e., the cooperation principle of slider and rail. After final installation, the top surface of the slider is flush with the surface of the base. The sliding cooperation between the slider and the guide rail ensures that the lower left quarter-cylindrical measuring piece and the upper right quarter-cylindrical measuring piece move smoothly, allowing them to move smoothly along a predetermined straight line.

[0032] Specifically, the height of the four quarter-cylindrical measuring elements 2 on the base 1 must be consistent. This ensures that the adjusting rod positioned between two adjacent quarter-cylindrical measuring elements remains horizontal at all times.

[0033] In this embodiment, each quarter-cylindrical measuring element 2 has a protrusion 5 on its outer convex arc surface, and the four protrusions 5 are located on the same plane. When the rectangular sealing ring is fitted onto these four quarter-cylindrical measuring elements, the protrusion design can restrict the position of the corner of the rectangular sealing ring on the outer convex arc surface of the quarter-cylindrical measuring element, preventing the corner of the rectangular sealing ring from sliding down, so that the rectangular sealing ring is on a horizontal base surface, which facilitates a more accurate reading of the straight side length of the rectangular sealing ring.

[0034] In this embodiment, the adjusting rod 3 is cylindrical. The lower left quarter-cylindrical measuring piece 2b, the upper right quarter-cylindrical measuring piece 2c, and the lower right quarter-cylindrical measuring piece 2d are all provided with shaft holes 21 for the adjusting rod 3 to be inserted into. The cylindrical adjusting rod 3 slides into the shaft holes 21. The cylindrical shape of the adjusting rod has the characteristics of symmetry and isotropy, which makes it highly stable when it slides relative to the quarter-cylindrical measuring pieces, and the quarter-cylindrical measuring pieces move more smoothly.

[0035] It is worth noting that on the upper left quarter-cylindrical measuring piece 2a, the zero mark of the scale line 31 on the adjusting rod 3 is aligned with the axial cut surface of the upper left quarter-cylindrical measuring piece 2a. This ensures that the starting point of the measurement is accurate, thus avoiding measurement errors caused by an inaccurate starting point. It also makes the measurement process more intuitive and convenient, reducing the adjustment and calibration steps during measurement.

[0036] In this embodiment, the two adjusting rods 3 on the upper left quarter-cylindrical measuring piece 2a are on the same plane, and the height of the two adjusting rods 3 is higher than the height of the adjusting rods 3 on the lower left quarter-cylindrical measuring piece 2b and the upper right quarter-cylindrical measuring piece 2c. This ensures that the four adjusting rods do not interfere with each other and do not affect the displacement of the quarter-cylindrical measuring pieces.

[0037] In this embodiment, handles 6 are symmetrically arranged on both sides of the base 1, which facilitates the movement of the device by workers.

[0038] The above descriptions are merely some embodiments of this utility model. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this utility model, and all such modifications and improvements fall within the protection scope of this utility model.

Claims

1. A manual circumference measuring device for a rectangular sealing ring, characterized by, Four quarter-cylinder measuring members are arranged on the base, and the four quarter-cylinder measuring members are erected at the four corners of the rectangle, are always symmetrical up and down or left and right with the center line of the rectangle as the symmetrical axis, and are cylindrical when the four quarter-cylinder measuring members are completely folded to the center of the rectangle; The left upper quarter-cylinder measuring member is fixedly arranged on the base, two adjusting rods are vertically arranged on two axial sections of the left upper quarter-cylinder measuring member, and the two adjusting rods are respectively movably penetrated into one axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member; The other three quarter-cylinder measuring members are relatively slid with the base; The other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member is also vertically provided with an adjusting rod, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring member, the two adjusting rods are vertically arranged on the other axial section of the left lower quarter-cylinder measuring member and the right upper quarter-cylinder measuring ​ 2. The manual perimeter measuring device for a rectangular sealing ring according to claim 1, characterized by ​ 3. The manual perimeter measuring device for a rectangular sealing ring according to claim 2, characterized in that ​ 4. The manual perimeter measuring device for rectangular sealing rings according to claim 1, characterized in that ​ 5. The manual perimeter measuring device for rectangular sealing rings according to claim 1, characterized in that ​ 6. The manual perimeter measuring device for rectangular sealing rings according to claim 1, characterized in that ​ 7. The manual perimeter measuring device for rectangular sealing rings according to claim 1, characterized in that ​ 8. The manual perimeter measuring device for rectangular sealing rings according to claim 1, characterized in that ​

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