KR200450453Y1 - Spring scales for laboratory equipment with measurement everywhere - Google Patents

Spring scales for laboratory equipment with measurement everywhere Download PDF

Info

Publication number
KR200450453Y1
KR200450453Y1 KR2020100004607U KR20100004607U KR200450453Y1 KR 200450453 Y1 KR200450453 Y1 KR 200450453Y1 KR 2020100004607 U KR2020100004607 U KR 2020100004607U KR 20100004607 U KR20100004607 U KR 20100004607U KR 200450453 Y1 KR200450453 Y1 KR 200450453Y1
Authority
KR
South Korea
Prior art keywords
spring
scale
main body
weight
indicator
Prior art date
Application number
KR2020100004607U
Other languages
Korean (ko)
Inventor
전영인
Original Assignee
전영인
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 전영인 filed Critical 전영인
Priority to KR2020100004607U priority Critical patent/KR200450453Y1/en
Application granted granted Critical
Publication of KR200450453Y1 publication Critical patent/KR200450453Y1/en

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01G—WEIGHING
    • G01G23/00—Auxiliary devices for weighing apparatus
    • G01G23/18—Indicating devices, e.g. for remote indication; Recording devices; Scales, e.g. graduated
    • G01G23/20—Indicating weight by mechanical means
    • G01G23/206—Indicating weight by mechanical means special graduated scales therefor
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01G—WEIGHING
    • G01G3/00—Weighing apparatus characterised by the use of elastically-deformable members, e.g. spring balances
    • G01G3/02—Weighing apparatus characterised by the use of elastically-deformable members, e.g. spring balances wherein the weighing element is in the form of a helical spring
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09B—EDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS
    • G09B23/00—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes
    • G09B23/06—Models for scientific, medical, or mathematical purposes, e.g. full-sized devices for demonstration purposes for physics

Landscapes

  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computational Mathematics (AREA)
  • Mathematical Analysis (AREA)
  • Mathematical Optimization (AREA)
  • Mathematical Physics (AREA)
  • Pure & Applied Mathematics (AREA)
  • Business, Economics & Management (AREA)
  • Algebra (AREA)
  • Educational Administration (AREA)
  • Educational Technology (AREA)
  • Theoretical Computer Science (AREA)
  • Force Measurement Appropriate To Specific Purposes (AREA)

Abstract

The present invention forms a plurality of scale slots in the main body, and the position of the indicator moving downward in the longitudinal direction in the moving space of the scale slot by the elastic force of the spring and the scale displayed around the scale slot This invention relates to a spring balance for laboratory equipment that can be measured in four directions with a structure that allows the user to easily check the measurement results of objects from all directions by contrast. This makes it possible to accurately and efficiently read the measurement result of the object weight by eliminating the movement of the moving object when measuring the weight of the object. It is possible to discriminate by using high education effect and the structure of scale is firm It is an advantage that it is a structure suitable for experimental equipment of elementary school students who are inexperienced in handling various materials.

Description

Spring balance for measuring confirmation of all directions

The present invention forms a plurality of scale slots in the main body, and the measurement results of the object in all directions by contrast with the scale and the position of the indicator moving downward in the movement space of the scale slot by the spring's elastic force As a structure that can be easily identified with the naked eye, it is suitable for the experimental equipment for students to improve the educational effect, it is related to the spring balance for experimental equipment capable of confirming the measurement on all sides.

In particular, the present invention is to check the four-sided measurement to ensure that the weight of the object can be accurately and efficiently by eliminating the movement of the moving object when measuring the weight of the object by engaging the shaft of the indicator in the locking groove formed on the scale of the main body It relates to a spring balance for possible experimental equipment.

As shown in FIG. 1, a general cylindrical spring scale includes a moving body 30 and a main body 20 for receiving the moving body 30 and the spring 1, and the upper end of the main body for fixing to a stator. The fixed hanger 3 and the lower end of the movable body 30 are provided with an object hanger 32 for hanging an object, respectively, and on one side of the main body 20 made of an opaque material, a viewing window 60 is displayed on the periphery. In this viewing window 60, the scale is checked by the indicator 40 extending downward in accordance with the weight of the object, and the weight of the object is measured, but the scale is formed only on one side of the main body 20. In the laboratory for many students, there was a problem that the educational effect was halved because there was a position where the scale of the spring scale could not be directly checked according to the position of the students.

As a method for solving the above problems, as shown in FIG. 2 in the Korean Utility Model Publication No. 20-0152347, the main body 20 is formed of a transparent tube, and a scale represented by a predetermined interval is provided on the main body ( 20) is expressed on the entire circumference, the weight display numerals are displayed on all sides of the main body 20, and the movable body 30 is a columnar type, characterized in that the upper and lower parts on the basis of the 0 point is expressed in complementary colors Although the spring scale is used for the experimental equipment of elementary school students, the main body is made of synthetic resin tubes made of transparent materials such as PET, PP, acrylic, etc. There was a problem that the tube is easily broken.

On the other hand, it is a spring balance having a structure different from the cylindrical spring scale, one graduation slot in the longitudinal direction of the main body in the center of the cross-section main body 20 and the cross-section main body 20 is marked as shown in Figure 3 (24) is formed, the cross-sectional spring balance that measures the weight of the object by the indicator 40 coupled to the moving body moving in the lower direction in accordance with the weight of the object on the scale slot is robust and the handling of the experimental equipment is inexperienced Although it is suitable to be used for experimental equipment of an elementary school student, there is a problem that the effect of education is halved because the result of measuring the weight of the object cannot be seen from all directions.

On the other hand, as shown in Figure 4 of the US Patent Publication No. 1141562 to solve the problems described in Figures 1 to 3 above, the graduation slots 24 are formed in opposite directions, the image on the graduation slot 24 The spring scale has been proposed to measure the weight of an object by the indicator 40 which is moved downward. However, it is difficult for students to read the scale arbitrarily and accurately measure the weight of the object in the process of measuring the weight of the object. There was a difficulty.

Therefore, the present invention as a way to solve the above problems is to form a plurality of graduation slots in the main body, while moving in the downward direction in the movement space of the graduation slot is displayed at the proper position by the elastic force of the spring according to the weight of the object This spring is designed to measure the weight of an object by comparing its self-stopped position with a scale, and it is possible to easily determine the measurement result of the weight of an object from all directions with the naked eye. The task is to provide a spring balance.

In particular, the present invention allows the indicator to be hooked to the locking groove formed on the scale of the main body, thereby eliminating the movement of the moving object when measuring the weight of the object, so that the measurement of the weight of the object can be accurately and efficiently measured everywhere. The task is to provide a spring balance for laboratory equipment.

Therefore, the present invention is a structure in which the indicator coupled to the moving object moving by the weight of the object is moved inside the moving space formed in the graduation slot, and the structure of the scale is firm so that the measurement result can be accurately and easily read, and various equipments. The object of the present invention is to provide a spring scale for experimental equipment that can be measured in all directions, characterized in that the structure is suitable for experimental equipment for elementary school students who are inexperienced.

The present invention for achieving the above object in the spring scale for measuring the weight of the object using a deformation of the spring (1), the spring (1) has a hollow 22 accommodated to be stretchable in the vertical direction And four graduation slots each formed on four or circumferential surfaces, each of which is formed to have a rectangular cross section or a circular cross section, and penetrates outward to communicate with the hollow 22 at predetermined intervals and has a predetermined length in the vertical direction. A main body 20 with 24; A movable body (30) inserted into the hollow (22) of the main body (20) so that one end thereof is movable and coupled to the spring (1) to connect the measurement product to the outside; An indicator 40 coupled to the movable body 30 so as to be movable upward and downward on the movable space 21 of the graduation slot 24; Four graduation slots 24 of the main body 20 communicate with each other, and the engaging grooves 27 are formed on the graduations 25, respectively, and the indicator 40 includes the body 42 and the body 42. It has a shaft 48 and a screw 44 is formed to be movable along the graduation slot 24 at the tip of the, and has a tool groove 46 formed at the rear end of the body 42, the movable body 30 ) Is provided with a screw groove 31 to which the screw 44 is coupled to the coupling position of the indicator 40, the shaft 48 of the indicator 40 is the scale of the main body 20 ( It is characterized in that the movement of the movable body 30 is fixed by being fitted into the engaging groove 27 formed on the 25 to measure the weight of the object.

In the spring balance for the experimental equipment capable of confirming the measurement in all directions according to the present invention as described above, the movable body 30 is characterized in that it further comprises a pedestal 34 is formed on the lower side.

The present invention by means of the above problem solving means to form a plurality of scale slots in the body, the spring to weigh the object by comparing the scale displayed around the scale slot with the stop position of the indicator coupled to the moving object in the moving space of the scale slot As a balance, in particular, by measuring the weight of an object accurately and efficiently by fixing the indicator to a locking groove formed on the scale, there is no movement of the indicator when measuring the weight of the object, so that the weight of the accurate object can be effectively measured. .

Therefore, the results of accurate measurement of the weight of the object can be easily determined by the naked eye regardless of the student's position when experimenting with the elementary school students. The education effect is high and the structure of the scale is solid, so handling of various materials is immature. The advantage is that the structure is suitable for the experimental equipment of an elementary school student.

1 is a perspective view showing the internal structure of a conventional cylindrical spring scale body is made of an opaque material,
Figure 2 is a perspective view showing the structure of another conventional cylindrical spring scale body is made of a transparent material,
3 and 4 is a front view showing a conventional spring scale,
Figure 5 is a perspective view showing the internal structure of the spring balance for the experimental equipment capable of confirming measurement in all directions as a preferred embodiment according to the present invention,
6 is a cross-sectional view taken along the line A-A 'of the spring balance body for experimental equipment capable of confirming measurement in all directions of FIG.
FIG. 7 is an exploded perspective view in which parts of a spring balance for an experimental equipment that can be measured and checked in four directions are separated from each other; FIG.
8 is a perspective view showing a state of use when measuring the spring balance for the experimental equipment capable of confirming the measurement of Figure 4,
Figure 9 is another preferred embodiment according to the present invention, relates to a perspective view showing the internal structure of the spring balance for the experimental equipment capable of confirming the measurement of the four-sided cylindrical structure of the main body.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail with reference to Figures 4 to 8, in the drawings and detailed description of the configuration and operation that can be easily understood by those skilled in the art from the common spring scale Illustrations and references are briefly or omitted. In particular, in the drawings and detailed description of the drawings, detailed descriptions and illustrations of specific technical configurations and operations of elements not directly related to the technical features of the present invention are omitted, and only the technical configurations related to the present invention are briefly shown or Explained.

When described in detail with reference to the accompanying drawings, the technical idea according to the features of the present invention as follows.

Figure 4 is a preferred embodiment according to the present invention, a perspective view showing the internal structure of the spring balance for the experimental equipment capable of confirming the measurement in all directions, Figure 5 is a body of the spring balance body for experimental measurement capable of confirming the measurement of Figure 4 Fig. 6 is an exploded perspective view showing a cut-away view of the surface, and FIG. 6 is an exploded perspective view of a component of a spring balance capable of confirming the measurement in all directions of FIG. 4, and FIG. 8 is a perspective view illustrating a state of use when measuring a spring balance, and FIG. 8 is a perspective view illustrating an internal structure of a spring balance for laboratory equipment that can be measured in four directions having a cylindrical structure of a main body as another preferred embodiment of the present invention. will be.

4 to 8, a plurality of graduation slots 24 are formed in the main body 20 having hollows 22 formed therein, and the moving spaces 21 are formed in the graduation slots 24. The moving body 30, which is moved downward by the spring force of the spring while moving according to the weight of the object and then stopped by the elongation length of the spring 1, and the indicator coupled to the moving body 30 As a principle of measuring the weight of an object by comparing the position of 40 and the scale 25, it is easy to visually discriminate the measurement result of the object from all directions irrespective of the position of the measuring instrument.

The four-sided measurement check spring according to the present invention having the application principle as described above is a four-sided measurement check spring having a rectangular cross-sectional structure as shown in Figure 4 according to the cross-sectional structure of the main body 20 as shown in FIG. It can be applied to all four sides of the spring for confirmation of measurement with the same circular cross-sectional structure.

And described in detail with reference to Figure 4 attached to the main configuration of the four-side measurement confirmation spring according to a preferred embodiment of the present invention as follows.

As shown in FIG. 4, the four-sided spring for confirming measurement according to the present invention includes a hollow body in which the spring 1 is stretchable in the vertical direction by a length in which the spring 1 extends according to the weight of the object by elastic force and restoring force. At least two graduation slots 24 are formed around the main body so as to penetrate outwardly so as to communicate with the hollow 22 at predetermined intervals and have a predetermined length in the vertical direction.

And a movable body 30 which is inserted into the hollow 22 of the main body 20 so that one end thereof is movable and coupled to the spring 1 so as to connect the measurement product to the outside, and the at least two graduation slots ( Including the indicators 40 are respectively coupled to the movable body 30 so as to be movable in the vertical direction by the elastic force and the restoring force of the spring on the moving space 21 of the 24, measuring in all directions according to an embodiment of the present invention Versatile spring balances are constructed.

In the above, the number of the graduation slots 24 should be formed at least two on the surface of the main body 20, the number can be appropriately adjusted according to the cross-sectional structure of the main body.

And the cross-sectional structure of the main body 20 is formed as shown in Figure 5 the main body 20 has a rectangular cross section or a circular cross section as shown in Figure 8, the graduation slot 24 is the main body ( It is characterized in that each of the four sides or the circumferential surface of 20), the cross-sectional structure of the main body can be applied to the cross-sectional structure of various shapes, such as five or six surfaces in addition to the cross-sectional structure defined above. .

And the four-side measurement spring for confirmation according to the present invention is formed in the body 42, the front end of the body 42, as shown in Figure 6, the shaft 48 is formed in a size that is movable on the graduation slot 24 And an indicator 40 having a screw 44, a tool groove 46 formed at a rear end of the body 42, and the screw 44 coupled to a coupling position of the indicator 40. A moving body 30 having a screw groove 31, a spring 1 extending by an elastic force according to the weight of the object, and at least four graduation slots 24 formed thereon, and the main body 20 on which the graduations 25 are displayed. ) At this time, a locking groove 27 is formed on the scale 25 of the main body 20 so as to communicate with the scale slot 24.

On the other hand, the movable body 30 is formed to further include a lower base 34 is placed on the object. The pedestal 34 may be able to measure the weight of the object when the object can not be placed. At this time, the base 34 is formed with a groove 342 so that the object is placed inside, and comprises a connector 344 is formed to the upper side from the edge of the groove 342 is coupled to the moving body 30.

As such, by further including the support 34 in the movable body 30, the weight of the weight or the object can be weighed at the same time, and the weight of another object can be measured. In addition, if the weight of the weight is heavy because the moving body 30 is lowered to the lower side, when the weight can not be measured by touching the ground there is an effect that can measure the weight on the base (34).

As shown in FIGS. 6 and 7, the spring scale for the experimental equipment capable of confirming the measurement of four directions composed of the above components first includes the upper hook 11 of the spring 1 and the upper end inside the hollow 22 of the body 20. Hooked on the spring hanger (26) located in the inserting the movable body 30 in the hollow interior of the body 20, the spring hook 33 provided on the upper end of the movable body 30 to the lower hook 12 of the spring (1) After the hook is coupled to the screw groove 31 formed on the outer surface of the moving body 30 in the moving space 21 of the scale slot 24 by using the screw 44 formed at the end of the indicator 40, the main body 20 And the moving body 30 are coupled to each other, and when measuring the weight of the object, the zero point adjusting screw 2 located at the top of the main body 20 is positioned on the moving space 21 of the graduation slot 24. The indicator 40 is adjusted to be positioned at the zero point of the scale, and then the weight of the object is measured. At this time, in order to accurately measure the weight of the object, the moving body 30 is rotated to the left and right to hang the indicator 40 on the engaging groove 27 of the graduation 25 formed in communication with the graduation slot 24. Ensure the scale is accurate even when the balance is touched.

As described above, the four-sided spring for confirming measurement according to the present invention forms a plurality of scale slots in the main body, and compares the scales displayed around the scale slots with the position where the indicator coupled to the moving object stops in the moving space of the scale slots. As a spring balance, in particular, by measuring the weight of an object accurately and efficiently by fixing the indicator to a locking groove formed on the scale, the weight of the object can be effectively measured because there is no movement of the indicator when measuring the weight of the object. It is characteristic.

On the other hand, in the present invention has been described by illustrating a method in which the spring (1) is coupled to the main body 20 and the moving body 30 by the above method, it can be coupled by various methods in addition to the above-described method.

Looking at the operation of the present invention configured according to one embodiment and this embodiment as described above are as follows.

First, by using the fixing hook (3) provided on the upper portion of the main body 20 to fix the spring for confirming the measurement (1) to the external fixing stand, the indicator 40 by using the zero-point adjustment screw (2) Is adjusted to be fixed at the position of the moving space 21 of the scale slot 24 marked with a scale of 0, and then the object is hooked to the object hanger 32 provided at the lower portion of the movable body 30. (1) is extended in the downward direction by the elastic force to move the movable body 30 by the length extending in the downward direction from the hollow 22 formed in the main body 20. At this time, the indicator 40 coupled to the movable body 30 is downward in the downward direction by the length of the spring 1 increased by elastic force along the moving space 21 of the graduation slot 24 on at least two sides. Move to and stop, and when the indicator 40 is stopped, the moving body 30 is rotated to the left and right to hang the shaft 48 of the indicator 40 to the locking groove 27 of the main body 20 Reading (25) gives the weight of the object.

The four-side measurement check spring according to the present invention having the structure as described above is marked on the four sides or the circumferential surface, so that the result of measuring the weight of the object can be easily read with the naked eye no matter what position the measuring instrument is, In particular, the present invention allows the indicator to be hooked to the locking groove formed on the scale of the main body, thereby eliminating the movement of the moving object when measuring the weight of the object, so that the measurement of the weight of the object can be accurately and efficiently measured everywhere. Spring balances for laboratory equipment can be provided.

Therefore, the present invention is a structure in which the indicator coupled to the moving object moving by the weight of the object is moved inside the moving space formed in the graduation slot, and the structure of the scale is firm so that the measurement result can be accurately and easily read, and various equipments. It is characterized in that the structure is suitable for experimental equipment of inexperienced elementary school students.

As described above, although the spring balance for the experimental equipment capable of confirming the measurement in all directions according to the preferred embodiment of the present invention is illustrated according to the above description and drawings, this is merely an example and does not depart from the technical spirit of the present invention. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope.

1: spring 2: 0 point adjustment screw
3: fixed hanger 11: upper hanger
12: lower hook 20: main body
21: moving space 22: hollow
24: graduation slot 25: graduation
26, 33: spring hanger 27: locking groove
30: moving body 31: screw groove
32: object hanger 34: pedestal
40: indicator 42: body
44: screw 46: tool groove
48: shaft

Claims (2)

In the spring scale which measures the weight of an object using the deformation of the spring 1,
The spring 1 has a hollow 22 accommodated to be stretchable in the vertical direction, is formed to have a rectangular cross section or a circular cross section, and is penetrated outward so as to communicate with the hollow 22 at predetermined intervals at the same time. A main body 20 having four graduation slots 24 formed on four or circumferential surfaces so as to have a predetermined length in a direction;
A movable body (30) inserted into the hollow (22) of the main body (20) so that one end thereof is movable and coupled to the spring (1) to connect the measurement product to the outside;
An indicator 40 coupled to the movable body 30 so as to be movable upward and downward on the movable space 21 of the graduation slot 24;
In communication with the four graduation slots 24 of the main body 20, the engaging grooves 27 are formed on the graduation 25, respectively,
The indicator 40 has a body 42 and a shaft 48 and a screw 44 movably formed along the graduation slot 24 at the tip of the body 42, the body 42 Has a tool groove 46 formed at the rear end of,
The movable body 30 is provided with a screw groove 31 to which the screw 44 is coupled to the coupling position of the indicator 40,
Since the shaft 48 of the indicator 40 is fitted into the locking groove 27 formed on the scale 25 of the main body 20, the movement of the movable body 30 is fixed to measure the weight of the object. A spring balance for laboratory equipment that can be checked in all directions, characterized in that it is possible to do so.
The method of claim 1,
The movable body 30 is formed on the lower side, the spring balance for experimental equipment capable of confirming the four-way measurement, characterized in that further comprises a pedestal 34 is placed.
KR2020100004607U 2010-04-30 2010-04-30 Spring scales for laboratory equipment with measurement everywhere KR200450453Y1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR2020100004607U KR200450453Y1 (en) 2010-04-30 2010-04-30 Spring scales for laboratory equipment with measurement everywhere

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR2020100004607U KR200450453Y1 (en) 2010-04-30 2010-04-30 Spring scales for laboratory equipment with measurement everywhere

Publications (1)

Publication Number Publication Date
KR200450453Y1 true KR200450453Y1 (en) 2010-10-08

Family

ID=44479189

Family Applications (1)

Application Number Title Priority Date Filing Date
KR2020100004607U KR200450453Y1 (en) 2010-04-30 2010-04-30 Spring scales for laboratory equipment with measurement everywhere

Country Status (1)

Country Link
KR (1) KR200450453Y1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102590325A (en) * 2012-03-19 2012-07-18 中国有色金属工业昆明勘察设计研究院 Grade estimation device for magnetite core
KR101243187B1 (en) 2011-06-09 2013-03-13 채호재 Spring scale
KR20150119586A (en) * 2014-04-16 2015-10-26 이애란 fire extinguisher mount with equipped of device to weight show

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US264070A (en) * 1882-09-12 Ohaeles foeschnee
US4078625A (en) 1977-02-09 1978-03-14 Loeb Robert D Moisture indicator for hanging plant containers

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US264070A (en) * 1882-09-12 Ohaeles foeschnee
US4078625A (en) 1977-02-09 1978-03-14 Loeb Robert D Moisture indicator for hanging plant containers

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101243187B1 (en) 2011-06-09 2013-03-13 채호재 Spring scale
CN102590325A (en) * 2012-03-19 2012-07-18 中国有色金属工业昆明勘察设计研究院 Grade estimation device for magnetite core
KR20150119586A (en) * 2014-04-16 2015-10-26 이애란 fire extinguisher mount with equipped of device to weight show
KR101713519B1 (en) * 2014-04-16 2017-03-08 이애란 fire extinguisher mount with equipped of device to weight show

Similar Documents

Publication Publication Date Title
KR102036510B1 (en) Jig for Rebound Hardness Test for Structural Safety Diagnosis
KR200450453Y1 (en) Spring scales for laboratory equipment with measurement everywhere
CN207380954U (en) A kind of high school student's Physical Experiment coefficient of elasticity measurement device
CN203727062U (en) Multifunctional protractor
CN203719599U (en) Measuring apparatus for measuring gap width
CN204514216U (en) A kind of slide calliper rule protractor
KR101377365B1 (en) Measuring device for hexagonal structure
CN212133531U (en) Wall gap width measuring device for detecting house building main body
CN109506588A (en) A multifunctional accurate surveys and draws measuring instrument practical traning platform
CN213209061U (en) Positioning punctuation device for exhibition design model
CN209910539U (en) Micropore detection device
KR200481125Y1 (en) Apparatus for measuring flexible air gap of multi-purpose
CN209404788U (en) Wound measuring scale
CN103745631B (en) Experiment demonstration device for measuring relation between friction force and tensile force
US4380963A (en) Movable limit markers for viewing glass of measuring instruments
CN203772189U (en) Diameter measuring ruler
CN206073899U (en) A kind of polymeter
CN206311026U (en) Slide calliper rule cubing
US20120003618A1 (en) Geo-meter graph reader learning system
CN206379074U (en) A kind of device for mathematical education
CN215177622U (en) Multifunctional measuring instrument
CN201161509Y (en) Drawing tool for pupil
CN211364088U (en) Trigonometric function learning ruler
CN215495593U (en) Force composition and decomposition demonstration device
CN206891334U (en) A kind of drum diameter survey tool

Legal Events

Date Code Title Description
A201 Request for examination
A302 Request for accelerated examination
E701 Decision to grant or registration of patent right
REGI Registration of establishment
LAPS Lapse due to unpaid annual fee