阅读说明：本技术 一种数显尖角塞尺 (Digital display closed angle clearance gauge ) 是由 张映碧 于 2021-10-08 设计创作，主要内容包括：本发明提供了一种数显尖角塞尺,属于建筑及加工制造测量工具技术领域。它解决了现有尖角塞尺测量不精确的技术问题。本数显尖角塞尺包括尺座,尺座上设有伸出的定位条和可沿定位条长度方向往复滑动的尺条,定位条和尺条沿长度方向平行设置,尺条的伸出端具有尖端朝尺条伸出方向设置的锐角板,其特征在于,定位条的外端具有尖端朝尺条伸出方向设置的三角板,三角板与锐角板平行,该锐角板的尖端能与三角板的尖端沿锐角板厚度方向重合,三角板尖端的夹角大于锐角板尖端的夹角,当尺条相对定位条伸出时,锐角板尖端的两侧边能沿锐角板厚度方向分别与三角板尖端的两侧边相交。本发明具有更高的测量精度。(The invention provides a digital display sharp-angle clearance gauge, and belongs to the technical field of building and processing and manufacturing measuring tools. It has solved the inaccurate technical problem of current closed angle clearance gauge measurement. This digital display closed angle clearance gauge includes the ruler base, be equipped with the location strip that stretches out on the ruler base and can follow the ruler strip of location strip length direction reciprocating sliding, location strip and ruler strip are along length direction parallel arrangement, the end that stretches out of ruler strip has the sharp scute that most advanced orientation ruler strip stretches out the orientation setting, a serial communication port, the outer end of location strip has the set-square that most advanced orientation ruler strip stretches out the orientation setting, the set-square is parallel with the acute angle board, the most advanced ability of this acute angle board and the most advanced coincidence of sharp-angle board thickness direction along the acute angle board, the most advanced contained angle of set-square is greater than the most advanced contained angle of acute angle board, when ruler strip relative positioning strip stretches out, the most advanced both sides limit of acute angle board can be crossed with the most advanced both sides limit of set-square respectively along acute angle board thickness direction. The invention has higher measurement precision.)

1. The digital sharp-corner feeler gauge comprises a gauge base (1), wherein a positioning strip (11) extending out and a gauge strip (2) capable of sliding in a reciprocating manner along the length direction of the positioning strip (11) are arranged on the gauge base (1), the positioning strip (11) and the gauge strip (2) are arranged in parallel along the length direction, a sharp corner plate (23) with a pointed end arranged towards the extending direction of the gauge strip (2) is arranged at the extending end of the gauge strip (2), the digital sharp-corner feeler gauge is characterized in that a triangular plate (111) with a pointed end arranged towards the extending direction of the gauge strip (2) is arranged at the outer end of the positioning strip (11), the triangular plate (111) is parallel to the sharp corner plate (23), the pointed end of the angular plate sharp corner (23) can be superposed with the pointed end of the triangular plate (111) along the thickness direction of the acute corner plate (23), the included angle of the pointed end of the triangular plate (111) is larger than the included angle of the pointed end of the sharp corner plate (23), and when the gauge strip (2) extends out relative to the positioning strip (11), two side edges of the sharp corner plate (23) can be respectively intersected with two side edges of the sharp corner plate (111) along the thickness direction of the sharp corner plate (23).

2. A digital readout feeler gauge according to claim 1, characterized in that the bisector of the angle of the tip of the set square (111) is arranged parallel to the bisector of the angle of the tip of the acute angle plate (23).

3. A digital readout feeler gauge according to claim 1 or 2, in which the angle of the tip of the acute angle plate (23) is 7-11 degrees and the angle of the tip of the set square (111) is 12-16 degrees.

4. The digital display closed angle feeler gauge according to claim 1 or 2, characterized in that the positioning bar (11) has a guide runner (12) arranged in the sliding direction relative to the gauge bar (2), the gauge bar (2) has a slide block (21), and the slide block (21) is embedded in the guide runner (12).

5. The digital sharp-corner feeler gauge comprises a gauge base (1), wherein a positioning strip (11) extending out and a gauge strip (2) capable of sliding in a reciprocating manner along the length direction of the positioning strip (11) are arranged on the gauge base (1), the positioning strip (11) and the gauge strip (2) are arranged in parallel along the length direction, a sharp corner plate (23) with a pointed end arranged towards the extending direction of the gauge strip (2) is arranged at the extending end of the gauge strip (2), the digital sharp-corner feeler gauge is characterized in that a triangular plate (111) with a pointed end arranged towards the extending direction of the gauge strip (2) is arranged at the outer end of the positioning strip (11), the triangular plate (111) is parallel to the sharp corner plate (23), the pointed end of the angular plate sharp corner (23) can be superposed with the pointed end of the triangular plate (111) along the thickness direction of the acute corner plate (23), the included angle of the pointed end of the triangular plate (111) is larger than the included angle of the pointed end of the sharp corner plate (23), and when the gauge strip (2) extends out relative to the positioning strip (11), one side of the sharp corner plate (23) tip is always overlapped with one side of the triangle plate (111) tip along the thickness direction of the sharp corner plate (23), and the other side of the sharp corner plate (23) tip can be crossed with the other side of the triangle plate (111) tip along the thickness direction of the sharp corner plate (23).

6. The digital display sharp angle feeler gauge according to claim 5, characterized in that a return spring (4) arranged along the length direction of the gauge strip (2) is arranged between the inner end of the gauge strip (2) and the gauge base (1), and two ends of the return spring (4) are respectively abutted against the inner end of the gauge strip (2) and the gauge base (1).

7. The digital display sharp angle feeler gauge according to claim 6, wherein the inner end of the gauge strip (2) is provided with a protruding positioning block (24), the gauge base (1) is internally provided with a positioning column (13) which is opposite to the positioning block (24) along the length direction of the gauge strip (2), and two ends of the return spring (4) are respectively sleeved on the peripheries of the positioning block (24) and the positioning column (13).

8. A digital display closed angle feeler gauge according to claim 5, characterized in that the blade (2) is provided with a stop plate (25), the stop plate (25) being able to abut against the base (1) or against the positioning strip (11) and prevent the blade (2) from continuing to protrude when the blade (2) is extended.

9. The digital display closed angle feeler gauge according to claim 1 or 5, characterized in that the gauge base (1) is provided with a digital display module (3) for measuring and displaying measurement data, and the gauge strip (2) is provided with a reference dial button (22) capable of re-determining the calculation reference of the digital display module (3) by pressing.

10. The digital readout feeler gauge according to claim 1 or 2 or 5 or 6 or 7 or 8, in which the distance between the tip of the acute angle plate (23) and the tip of the triangle (111) along the relative sliding direction is equal to the length of the line connecting the points of intersection of the two sides of the acute angle plate (23) with the two sides of the triangle (111).

Technical Field

The invention belongs to the technical field of building and processing and manufacturing measuring tools, and relates to a digital display sharp-angle clearance gauge.

Background

Actual measurement is required in the building construction and manufacturing process, the construction and the matching quality of various products are guaranteed, and economic loss caused by reworking due to construction errors is avoided. The wedge-shaped feeler gauge is a commonly used measuring tool for measuring the gap width in construction.

The patent with application publication number CN112240731A discloses a digital display feeler gauge for measuring small apertures, wherein a vernier is slidably mounted on a main gauge, one end of the vernier is fixedly connected with a positioning block, one end of the main gauge is fixedly connected with the bottom surface of a semi-conical feeler gauge, and the vertical section of the semi-conical feeler gauge is tightly attached to the side surface of the positioning block; when the main ruler and the vernier are tightened, the vertex of the semi-conical feeler gauge is aligned with the end part of the positioning block.

The feeler gauge is simple to operate, but is not a flat surface for the supporting surface of the periphery of the gap in the field of building and manufacturing, the positioning block is contacted with the supporting surface when in measurement, so that the position of the positioning block is higher than a theoretical position, or the interference between the actual working condition and the supporting surface causes that the tools cannot be used, and further the reading is not accurate enough.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a digital-display sharp-angle clearance gauge, which aims to solve the technical problems that: how to adapt to the clearance measurement of all kinds of different operating modes in order to improve the clearance's of clearance gauge measurement precision.

The purpose of the invention can be realized by the following technical scheme:

the utility model provides a digital display closed angle clearance gauge, includes the ruler base, be equipped with the location strip that stretches out on the ruler base and can follow location strip length direction reciprocating sliding's chi strip, the location strip with the chi strip is along length direction parallel arrangement, the end that stretches out of chi strip has the sharp scute that most advanced orientation chi strip stretched out the orientation and set up, its characterized in that, the outer end of location strip has the set square that most advanced orientation chi strip stretched out the orientation and set up, the set square with sharp scute is parallel, and the most advanced ability of this acute angle board and the most advanced coincidence of set square along acute angle board thickness direction, the most advanced contained angle of set square is greater than the most advanced contained angle of acute angle board, works as when chi strip relative positioning strip stretches out, the most advanced both sides limit of acute angle board can follow acute angle board thickness direction respectively with the most advanced both sides limit of set square is crossing.

The ruler base is an installation platform of the feeler gauge, the positioning strip is used for abutting against the edge of the gap or the hole to provide a reference for the ruler strip, and the extending end of the ruler strip is provided with an acute angle plate which is used for judging and measuring the size of the gap or the hole through the displacement of the ruler strip relative to the positioning strip after being gradually inserted into the gap or the hole to the right position. The outer end of the positioning strip is provided with a triangular plate with a pointed end arranged towards the extending direction of the ruler strip, the triangular plate is parallel to the acute angle plate, the pointed end of the acute angle plate can coincide with the pointed end of the triangular plate along the thickness direction of the acute angle plate, and the included angle of the pointed end of the triangular plate is larger than that of the pointed end of the acute angle plate, when the ruler strip relative positioning strip extends out, the two side edges of the pointed end of the acute angle plate can be respectively intersected or coincide with the two side edges of the pointed end of the triangular plate along the thickness direction of the acute angle plate, so that the pointed end of the acute angle plate and the pointed end of the triangular plate are simultaneously inserted into a gap during measurement, the two side edges of the pointed end of the triangular plate are simultaneously abutted against the edge of the gap, due to the fact that a cavity is arranged in the gap, the measurement error caused by the fact that the abutted position is smooth and can not be actually contacted is avoided, after the acute angle plate extends into the gap, the two side edges of the pointed end of the acute angle plate and the gap edge of the sharp angle plate can be adjusted to be abutted against the intersection point of the two side edges of the pointed end of the triangular plate to be abutted against the edge to be in place, at the moment, the intersection points of two sides of the sharp-angle plate tip and the triangular plate tip are both positioned at the edge of the gap, the positions of the intersection points are gradually changed in the measuring process, the width change of the intersection points is converted into horizontal displacement, and then the measuring data can be proportionally converted by judging the initial displacement of the ruler strip relative to the ruler base, preferably, a capacitive grating fixed grating digital display module can be used for realizing the purposes of direct conversion and visual numerical value display of the measured gap width; simultaneously acute scute side and set-square side form contained angle and gap edge cooperation and produce the location effect, do benefit to operating personnel through feeling calibration position and ensure the position stability when measuring, further improve measurement accuracy.

In the digital display sharp corner plug ruler, the bisector of the included angle at the tip end of the triangular plate and the bisector of the included angle at the tip end of the sharp corner plate are arranged in parallel. Make the most advanced structure symmetry along chi strip slip direction both sides of set-square and acute angle board like this, can guarantee more conveniently promptly when the chi strip slides that the nodical position of its most advanced both sides limit and the most advanced side of location strip is symmetrical along width direction, and then guarantee that chi strip and location strip are all just to inserting in the gap when the location is measured, reduce the whole skew of clearance gauge and the reading deviation that leads to, do benefit to and improve the reading precision.

In the digital display sharp corner plug ruler, the included angle of the tip end of the ruler strip is 7-11 degrees, and the included angle of the tip end of the positioning strip is 12-16 degrees. Under the condition of ensuring reasonable size adaptation, the size of the gap can be fully amplified to the relative displacement size of the ruler strip and the positioning strip, and reading precision is guaranteed.

In the digital display sharp corner plug ruler, the positioning strip is provided with the guide sliding groove arranged along the sliding direction relative to the ruler strip, the ruler strip is provided with the sliding block, and the sliding block is embedded in the guide sliding groove. Therefore, the ruler strip can be restrained and guided by the guide sliding groove, so that the direction of the ruler strip is more stable when the ruler strip slides, and the measurement precision is improved.

In the digital display sharp corner plug ruler, the ruler base is provided with a capacitive grid digital display module for displaying measured data. The capacitance grid digital display module is arranged on the ruler base and can comprise the existing digital display capacitance grid and a fixed grid module, the fixed grid module is arranged on the ruler strip, the displacement of the ruler strip is sensed through the capacitance grid sensor, the digital display capacitance grid is used for measuring and displaying measurement data, the data are displayed visually, and the reading efficiency and the reading precision can be improved.

A digital display sharp-angle clearance gauge comprises a gauge base, wherein the gauge base is provided with a positioning strip extending out and a gauge strip capable of sliding back and forth along the length direction of the positioning strip, the positioning strip and the ruler strip are arranged in parallel along the length direction, the extending end of the ruler strip is provided with a sharp angle plate with the tip end arranged towards the extending direction of the ruler strip, it is characterized in that the outer end of the positioning strip is provided with a triangular plate with the tip end arranged towards the extending direction of the ruler strip, the triangular plate is parallel to the acute angle plate, the tip of the acute angle plate can be coincided with the tip of the triangular plate along the thickness direction of the acute angle plate, the included angle of the tip of the triangular plate is larger than that of the tip of the acute angle plate, when the ruler strip extends out relative to the positioning strip, one side edge of the sharp end of the acute angle plate is always coincided with one side edge of the sharp end of the triangular plate along the thickness direction of the acute angle plate, the other side edge of the sharp end of the acute angle plate can be intersected with the other side edge of the sharp end of the triangular plate along the thickness direction of the acute angle plate. Similar with above-mentioned scheme, the most advanced side of set-square overlaps with the most advanced side of acute angle board and is unanimous with the chi strip slip direction, and the end that stretches out of chi strip and the outer end of locating bar all are the wedge like this, and sharp scute and set-square one side all need not be fixed a position by accident during the measurement, the simple operation.

In the digital display sharp corner plug ruler, the reset spring arranged along the length direction of the ruler strip is arranged between the inner end of the ruler strip and the ruler seat, and two ends of the reset spring are respectively abutted against the inner end of the ruler strip and the ruler seat. When a user needs to operate and measure, the sharp corner plate tip is inserted into the gap, the two side edges of the sharp corner plate abut against the edge of the gap, the triangular plate slides relative to the acute angle plate under the action of the force, the two side edges of the triangular plate abut against the edge of the gap to reach a measuring position, and the measuring and reading are carried out, so that the user can operate the ruler with one hand, and the ruler is convenient and fast to use; after the measurement is finished, the ruler strip can be automatically popped out, and the next measurement is convenient.

In the digital display sharp corner plug ruler, the inner end of the ruler strip is provided with the protruding positioning block, the ruler seat is internally provided with the positioning column which is just opposite to the positioning block along the length direction of the ruler strip, and two ends of the reset spring are respectively sleeved on the peripheries of the positioning block and the positioning column. The position of reset spring can obtain the location of locating piece and reference column like this, avoids its skew dislocation, improves the stability that the chi strip resets.

In the digital display sharp corner plug ruler, the ruler strip is connected with the limiting plate, and when the ruler strip extends out, the limiting plate can abut against the ruler seat or abut against the positioning strip and prevent the ruler strip from extending out continuously. Therefore, the stroke of the ruler strip can be limited, and the influence on measurement caused by the falling-off of the ruler strip from the ruler seat is avoided.

In the digital display sharp corner plug ruler, the ruler strip is provided with a reference toggle button which can re-determine the calculation reference of the capacitive gate digital display module through pressing. Therefore, an operator can reset the capacitive grating digital display module by pressing the control reference toggle button after the sharp corner plate and the triangular plate are controlled to be aligned at the tip end, and the problem that the capacitive grating digital display module cannot restore the measurement reference position after power failure is solved.

In the above digital display sharp corner plug ruler, the distance between the sharp corner plate and the triangular plate along the relative sliding direction is equal to the length of the connecting line of the intersection points of the two sides of the sharp corner plate and the two sides of the triangular plate. Therefore, the width dimension measured by the feeler gauge and the sliding distance dimension of the gauge strip relative to the reference position form a one-to-one relationship, the conversion difficulty can be reduced, and the measurement precision can be improved.

Compared with the prior art, the invention has the following advantages:

this digital display closed angle clearance gauge sets up sharp scute and the set-square that all is the closed angle form respectively through the tip that sets up chi strip and location strip, sharp scute and set-square point insert the gap simultaneously and make two hypotenuses at the set-square point tip support simultaneously and lean on in gap edge when measuring like this, because make the location strip can support with gap edge is actual to support in the gap for the cavity, avoid leveling and can not the actual measuring error that leads to because of supporting, improve measurement accuracy. The intersection points of the acute angle plate and the triangular plate side represent the width of the gap, the intersection points gradually change along with the horizontal displacement of the ruler strip, the change of the width size of the gap is converted into designed horizontal displacement, and numerical value display is realized through the mature function of the capacitance grid fixed grid digital display module in the market, so that the width numerical value of the gap is finally displayed.

Drawings

Fig. 1 is a schematic perspective view of a reset state in the present embodiment.

Fig. 2 is a schematic perspective view of the embodiment at another angle in a reset state.

Fig. 3 is a schematic perspective view of an operating state of the present embodiment.

Fig. 4 is a schematic perspective view of the first embodiment.

Fig. 5 is a schematic perspective view of the second reset state in the present embodiment.

Fig. 6 is a schematic partial perspective view of the second embodiment.

Fig. 7 is a perspective view of a second hidden part structure of the present embodiment.

In the figure, 1, a ruler base; 11. a positioning bar; 111. a set square; 12. a guide chute; 13. a positioning column;

2. a ruler strip; 21. a slider; 22. a reference dial button; 23. sharpening the corner plate; 24. positioning blocks; 25. a limiting plate;

3. a grid digital display module; 4. a return spring.

Detailed Description

The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.

The first embodiment is as follows:

as shown in fig. 1-3, the digital sharp-corner feeler gauge comprises a gauge base 1, a convex positioning strip 11 and a gauge strip 2 capable of sliding back and forth relative to the positioning strip 11 are arranged on the gauge base 1, the gauge strip 2 and the positioning strip 11 are arranged in parallel and attached to each other, an extending end of the gauge strip 2 is provided with a sharp corner plate 23 with a sharp end arranged towards the extending direction of the gauge strip 2, the outer end of the positioning strip 11 is provided with a triangular plate 111 with a sharp end arranged towards the extending direction of the gauge strip 2, the triangular plate 111 is parallel to the sharp corner plate 23, the sharp end of the sharp corner plate 23 can be overlapped with the sharp end of the triangular plate 111 along the thickness direction of the sharp corner plate 23, the included angle of the sharp end of the triangular plate 111 is larger than that of the sharp corner plate 23, and when the gauge strip 2 extends relative to the positioning strip 11, two side edges of the sharp end of the acute corner plate 23 can be respectively intersected with two side edges of the sharp end of the triangular plate 111 along the thickness direction of the acute corner plate 23. The ruler seat 1 is a mounting platform of the feeler gauge, the positioning strip 11 is used for abutting against the edge of the gap or hole to provide a reference for the ruler strip 2, and the acute angle plate 23 on the ruler strip 2 can be conveniently and gradually inserted into the gap or hole to be in place and then can judge and measure the size of the gap or hole through the displacement of the acute angle plate relative to the positioning strip 11. The outer end of the positioning strip 11 is provided with the triangular plate 111 with the tip end arranged towards the extending direction of the ruler strip 2, the tip end of the acute angle plate 23 and the tip end of the triangular plate 111 can be coincided along the thickness direction of the acute angle plate 23, and the included angle of the tip end of the triangular plate 111 is larger than that of the tip end of the acute angle plate 23, so that the tip end of the triangular plate 111 can be aligned with the tip end of the acute angle plate 23 when measurement is carried out, the triangular plate 111 is inserted into a gap and two bevel edges of the tip end of the triangular plate 111 are simultaneously abutted against the edge of the gap, the situation that the abutted part is flat and cannot be actually contacted to cause measurement errors is avoided, then the ruler strip 2 can be operated to slide out relative to the positioning strip 11 and further extend into the gap, the two bevel edges of the tip end of the acute angle plate 23 are abutted against the edge of the gap due to the gradual increase of the width of the extending part, and the intersection points of the two bevel edges of the tip end of the acute angle plate 23 and the triangular plate 111 are both positioned at the edge of the gap, the two form an included angle and the edge of the gap is matched to generate a certain positioning effect, so that the position is conveniently calibrated by an operator through hand feeling, the position stability during measurement is ensured, and the measurement precision is further improved. Further, the bisector of the angle at the tip of the triangle 111 is parallel to the bisector of the angle at the tip of the acute angle plate 23. Make the most advanced structure symmetry along chi strip 2 slip direction both sides of set square 111 point and acute angle board 23 point like this, can guarantee more conveniently when chi strip 2 slides promptly that the two hypotenuses at its acute angle board 23 point-like and the most advanced hypotenuse of set square 111 intersect the position along width direction symmetry, and then guarantee that chi strip 2 and location strip 11 are all just to inserting in the gap when the location is measured, reduce the whole skew of clearance gauge and the reading deviation that leads to, do benefit to and improve the reading precision. Preferably, the angle at the tip of the acute angle plate 23 is 9 degrees and the angle at the tip of the triangle plate 111 is 14 degrees. Under the condition of guaranteeing reasonable adaptation of size, make the gap size fully enlarge to the relative displacement size of chi strip 2 and location strip 11 like this, do benefit to and guarantee the reading precision. Preferably, the distance between the tip of the acute angle plate 23 and the tip of the triangular plate 111 along the relative sliding direction is equal to the length of the line connecting the intersection points of the two sides of the acute angle plate 23 and the two sides of the triangular plate 111. Therefore, the width dimension measured by the feeler gauge and the sliding distance dimension of the gauge strip 2 relative to the reference position form a one-to-one relationship, the conversion difficulty can be reduced, and the measurement precision can be improved.

As shown in fig. 1-4, the positioning bar 11 has a guiding sliding groove 12 arranged along the sliding direction relative to the blade 2, the blade 2 has a sliding block 21, and the sliding block 21 is embedded in the guiding sliding groove 12. Therefore, the ruler strip 2 can be restrained and guided by the guide sliding groove 12, so that the direction is more stable when the ruler strip slides, and the measurement precision is improved. The ruler strip 2 is provided with a reference dial button 22 which can re-determine the calculation reference of the capacitive grid digital display module 3 by pressing. Therefore, an operator can reset the reference position of the capacitive grid digital display module 3 by controlling the reference toggle button 22, and the problem that the capacitive grid digital display module 3 cannot be reset after power failure is avoided. The maximum width dimension of the blade 2 is the same as the maximum width dimension of the setting bar 11. Therefore, in the reset state, the tip of the measuring tape 2 is covered in the range of the tip of the positioning strip 11, and the measuring precision is prevented from being influenced by excessive abrasion of the measuring tape 2. Preferably, the ruler base 1 is provided with a capacitive digital display module 3 for displaying measured data. The capacitance grid digital display module 3 can adopt a commercially available module comprising a capacitance grid sensor, a microprocessor and a display screen, so that the capacitance grid digital display module 3 is arranged on the ruler base 1, the displacement is sensed by the capacitance grid sensor, and then the module measures, calculates, displays and measures the measured data in a digital display mode, and can improve the reading efficiency and precision.

Example two:

as shown in fig. 5 to 7, the present embodiment is substantially the same as the first embodiment, except that: the ruler strip 2 extends out of the positioning strip 11, when the ruler strip 2 extends out relative to the positioning strip 11, one side of the sharp corner plate 23 tip always coincides with one side of the triangular plate 111 tip along the thickness direction of the sharp corner plate 23, and the other side of the sharp corner plate 23 tip can intersect with the other side of the triangular plate 111 tip along the thickness direction of the sharp corner plate 23. A return spring 4 arranged along the length direction of the ruler strip 2 is arranged between the inner end of the ruler strip 2 and the ruler base 1, and two ends of the return spring 4 are respectively abutted against the inner end of the ruler strip 2 and the ruler base 1. Therefore, the reset spring 4 always provides an acting force extending outwards for the ruler strip 2, when a user needs to operate and measure, the sharp angle plate 23 is firstly inserted into the gap, the two side edges of the sharp angle plate are abutted against the edge of the gap, then the action is continued, the triangular plate 111 slides relative to the sharp angle plate 23, the two side edges of the triangular plate 111 are abutted against the edge of the gap to reach a measuring position, the reading is measured, the user can operate the ruler with one hand, and the use is convenient and fast; after the measurement is finished, the ruler strip 2 can be automatically ejected, so that the next measurement is convenient. Further, the inner end of the ruler strip 2 is provided with a protruding positioning block 24, the ruler base 1 is internally provided with a positioning column 13 which is opposite to the positioning block 24 along the length direction of the ruler strip 2, and two ends of the return spring 4 are respectively sleeved on the peripheries of the positioning block 24 and the positioning column 13. Therefore, the position of the reset spring 4 can be positioned by the positioning block 24 and the positioning column 13, so that the deviation and dislocation of the positioning block and the positioning column are avoided, and the reset stability of the ruler strip 2 is improved. The top of the ruler strip 2 is connected with a limiting plate 25, when the ruler strip 2 extends out, the limiting plate 25 can abut against the rear end of the positioning strip 11 and prevent the ruler strip 2 from extending out continuously. Therefore, the stroke of the ruler strip 2 can be limited, and the influence on measurement caused by the falling-off of the ruler strip 2 from the ruler base 1 is avoided.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.