CN203759978U - Multi-functional four-rod mechanism function demonstrating and teaching apparatus - Google Patents
Multi-functional four-rod mechanism function demonstrating and teaching apparatus Download PDFInfo
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- CN203759978U CN203759978U CN201420135349.1U CN201420135349U CN203759978U CN 203759978 U CN203759978 U CN 203759978U CN 201420135349 U CN201420135349 U CN 201420135349U CN 203759978 U CN203759978 U CN 203759978U
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- side link
- connecting rod
- hinge
- teaching aid
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Abstract
The utility model discloses a multi-functional four-rod mechanism function demonstrating and teaching apparatus which comprises a first rack connection rod, a first connection rod, a second rack connection rod, a rack, a third rack connection rod, a second connection rod and a fourth rack connection rod. The first rack connection rod is hinged with the first connection rod; the other end of the first connection rod is hinged with the second rack connection rod; the other end of the second rack connection rod is hinged with the rack; the other end of the rack is hinged with the other end of the first rack connection rod; the third rack connection rod is hinged with the second connection rod; the other end of the second connection rod is hinged with the fourth rack connection rod; the other end of the fourth rack connection rod is hinged with the rack; the other end of the rack is hinged with the other end of the third rack connection rod. The utility model is capable of directly demonstrating the basic structure and the functioning characteristics of the four-rod mechanism as well as the existing conditions for cranks. Low in cost and simple in operations, the utility model is also convenient to use.
Description
Technical field
The utility model belongs to mechanical major teaching aid field, is specifically related to a kind of multi-functional four-bar mechanism operating characteristic demonstration teaching aid.
Background technology
In mechanical, near machine class professional teaching, four-bar linkage is the basis of planar linkage mechanism, be the very important content of courses, student need to grasp the contents such as fundamental type, operating characteristic, Grashof's criterion and dimension synthesis of four-bar mechanism in the process of study.And there is the single or awkward shortcoming of size in existing demonstration teaching aid, although the bar having is long adjustable, can demonstrate fundamental type principle of work, but for emphasis, difficult point, operating characteristic in four-bar linkage study, all can not obviously demonstrate, affect student to the study of this part knowledge and understanding.
Summary of the invention
In order to overcome the shortcoming of above-mentioned prior art, the purpose of this utility model is to provide a kind of multi-functional four-bar mechanism operating characteristic demonstration teaching aid, fundamental type, operating characteristic, Grashof's criterion and the dimension synthesis etc. that can demonstrate intuitively four-bar mechanism, have cost feature low, simple to operate, easy to use.
In order to achieve the above object, the technical scheme that the utility model is taked is:
A kind of multi-functional four-bar mechanism operating characteristic demonstration teaching aid, comprise: the first side link 1, first connecting rod 2, the second side link 3, frame 4, the 3rd side link 5, second connecting rod 6 and the 4th side link 7, described the first side link 1 is two length-adjustable supports that size is identical with structure with the 3rd side link 5, described first connecting rod 2 is two supports that size is identical with structure with second connecting rod 6, described the second side link 3 is two supports that size is identical with structure with the 4th side link 7, one end of one end of described the first side link 1 and first connecting rod 2 is connected through the hinge, one end of the other end of described first connecting rod 2 and the second side link 3 is connected through the hinge, one end of the other end of described the second side link 3 and frame 4 is connected through the hinge, the other end of the other end of described frame 4 and the first side link 1 is connected through the hinge, one end of one end of described the 3rd side link 5 and second connecting rod 6 is connected through the hinge, one end of the other end of described second connecting rod 6 and the 4th side link 7 is connected through the hinge, one end of the other end of described the 4th side link 7 and frame 4 is connected through the hinge, the other end of the other end of described frame 4 and the 3rd side link 5 is connected through the hinge, described first connecting rod 2 is provided with the 3rd member 21, chute 22, the 3rd member 21 is positioned at chute 22, described the second side link 3 is provided with the 4th member 31, described the 4th member 31 connects with the second side link 3 by hinge.
Described the first side link 1 and the 3rd side link 5 are connected to form by the first member 11 and second component 12 respectively, described the first member 11 is provided with the straight pin being parallel to each other 14 of a plurality of projections, described second component 12 is provided with a plurality of circular holes that are parallel to each other 13, described circular hole 13 matches with the structure of straight pin 14, described straight pin 14 can insert the interior length to the first side link 1 of circular hole 13 and regulate, described straight pin 14 lower ends are provided with spring 9, described spring 9 connecting cylinder pin 14 lower ends, one end, the other end connects second component 12, described spring 9 can promote straight pin 14 card and in circular hole 13 the insides, length to the first side link plays fixation.
Described the first member 11 and second component 12 surfaces are provided with scale, and scale unit is cm.
In described first connecting rod 2, be provided with chute 22, described the 3rd member 21 is accommodated in chute 22, and described the 3rd member 21 can be interior protruding from chute 22.
Described the 4th member 31 connects with the second side link 3 by hinge, and described the 4th member 31 can forward rotation 90 be spent, and from the second side link 3, spins out.
The revolute pair 8 at described all hinges place is hollow circular hole, and is surrounded by TR thin rubber material, and described revolute pair 8 can be loaded onto chalk and use as drawing instrument.
Principle of work of the present utility model is:
When only using the first side link 1, first connecting rod 2, the second side link 3 and frame 4, press the length that the first side link 1 straight pin 14 above regulates the first side link 1, when meet stock and quarter butt length sum should≤other two pole lengths sums, when other three bar of Length Ratio of the first side link 1 all in short-term, this teaching aid can be used for demonstrating the principle of work of crank and rocker mechanism, double-crank mechanism.When regulating the length of the first side link 1, make not meet between each bar stock and quarter butt length sum should≤during other two pole lengths sums, this teaching aid can be used for demonstrating the principle of work of double rocker mechanism.This method is used teaching aid to can be used for demonstrating four-bar linkage fundamental type: the principle of work of crank and rocker mechanism, double-crank mechanism and double rocker mechanism and mechanism inversion principle.In like manner, when only using the 3rd side link 5, second connecting rod 6, the 4th side link 7 and frame 4, method is identical.
When using the first side link 1, first connecting rod 2, the second side link 3, frame 4, the 3rd side link 5, second connecting rod 6 and the 4th side link 7 simultaneously, regulate the length of the first side link 1 and the 3rd side link 5, make their length identical, rotate the 3rd side link 5 and second connecting rod 6 conllinear, towards the direction contrary with the 3rd side link 5, rotate the first side link 1 and first connecting rod 2 conllinear, at this moment the 3rd side link 5 and the 4th side link 7 are respectively in extreme position, and this method teaching aid can be used for demonstrating four-bar linkage extreme position and crank angle between two limit positions.
The 3rd member 21 is arranged in the chute 22 of first connecting rod 2, protractile during use, and the 4th member 31 connects with the second side link 3 by hinge, opens 90 degree angles during use.When the 3rd member 21 is overhanging, open while spending for 3 one-tenth 90 with the second side link with the 4th member 31, in rotating the process of the first side link 1, angle between the 3rd member 21 and the 4th member 31 gradually changes, and can be used for demonstrating the force-transfer characteristic of four-bar linkage with this teaching aid.When the first side link 1 and frame 4 conllinear, this teaching aid can be used for demonstrating the mechanism position that four-bar linkage minimum transmission angle occurs.
Length-adjustable the first side link 1, comprises second component 12 with straight pin 14, with the first member 11 of some circular holes 13, and straight pin 14 matches with circular hole 13, and straight pin 14 lower ends are connected with spring 9.The ingredient of length-adjustable the 3rd side link 5 is identical with the first side link 1.Length-adjustable the first side link 1, has length scale on its first member 11 and second component 12; On the composition member of length-adjustable the 3rd side link 5, there is too scale.While changing bar length, press down straight pin 14, Compress Spring 9, shrinking connecting-rod, is adjusted to suitable length, and straight pin 14 ejects from corresponding circle hole 13, and length is determined.This teaching aid can be used for demonstrating the Grashof's criterion of four-bar linkage.
The revolute pair 8 at all hinges place is hollow circular hole, and is surrounded by TR thin rubber material.In hole, insert chalk, make this teaching aid can be used as drawing instrument and use.
The beneficial effects of the utility model are: can demonstrate intuitively fundamental type, operating characteristic, Grashof's criterion and the dimension synthesis etc. of four-bar mechanism, have cost feature low, simple to operate, easy to use.
Accompanying drawing explanation
Fig. 1 is front view of the present utility model.
Fig. 2 is left view of the present utility model.
Fig. 3 is the front view of the first side link 1.
Fig. 4 is the rear view of the 3rd side link 5.
Fig. 5 is the structural representation of second component 12.
Fig. 6 is the structural representation of the second side link 3.
Fig. 7 is the operating characteristic demonstration mechanism location drawing.
Fig. 8 is the inner structure schematic diagram of second component 12.
Embodiment
Below in conjunction with accompanying drawing, the utility model is described in further detail.
Referring to accompanying drawing, a kind of multi-functional four-bar mechanism operating characteristic demonstration teaching aid, comprise: the first side link 1, first connecting rod 2, the second side link 3, frame 4, the 3rd side link 5, second connecting rod 6 and the 4th side link 7, described the first side link 1 is two length-adjustable supports that size is identical with structure with the 3rd side link 5, described first connecting rod 2 is two supports that size is identical with structure with second connecting rod 6, described the second side link 3 is two supports that size is identical with structure with the 4th side link 7, one end of one end of described the first side link 1 and first connecting rod 2 is connected through the hinge, one end of the other end of described first connecting rod 2 and the second side link 3 is connected through the hinge, one end of the other end of described the second side link 3 and frame 4 is connected through the hinge, the other end of the other end of described frame 4 and the first side link 1 is connected through the hinge, one end of one end of described the 3rd side link 5 and second connecting rod 6 is connected through the hinge, one end of the other end of described second connecting rod 6 and the 4th side link 7 is connected through the hinge, one end of the other end of described the 4th side link 7 and frame 4 is connected through the hinge, the other end of the other end of described frame 4 and the 3rd side link 5 is connected through the hinge, described first connecting rod 2 is provided with the 3rd member 21, chute 22, the 3rd member 21 is positioned at chute 22, described the second side link 3 is provided with the 4th member 31, described the 4th member 31 connects with the second side link 3 by hinge.
Described the first side link 1 and the 3rd side link 5 are connected to form by the first member 11 and second component 12 respectively, described the first member 11 is provided with the straight pin being parallel to each other 14 of a plurality of projections, described second component 12 is provided with a plurality of circular holes that are parallel to each other 13, described circular hole 13 matches with the structure of straight pin 14, described straight pin 14 can insert the interior length to the first side link 1 of circular hole 13 and regulate, described straight pin 14 lower ends are provided with spring 9, described spring 9 connecting cylinder pin 14 lower ends, one end, the other end connects second component 12, described spring 9 can promote straight pin 14 card and in circular hole 13 the insides, length to the first side link plays fixation.
Described the first member 11 and second component 12 surfaces are provided with scale, and scale unit is cm.
In described first connecting rod 2, be provided with chute 22, described the 3rd member 21 is accommodated in chute 22, and described the 3rd member 21 can be interior protruding from chute 22.
Described the 4th member 31 connects with the second side link 3 by hinge, and described the 4th member 31 can forward rotation 90 be spent, and from the second side link 3, spins out.
The revolute pair 8 at described all hinges place is hollow circular hole, and is surrounded by TR thin rubber material, and described revolute pair 8 can be loaded onto chalk and use as drawing instrument.
Referring to Fig. 1, Fig. 2, Fig. 6, the utility model comprises frame 4, length-adjustable the first side link 1 and frame 4 chain connections, first connecting rod 2 and length-adjustable the first side link 1 chain connection, first connecting rod 2 and the second side link 3 chain connections, the second side link 3 and frame 4 chain connections, with measure-alike length-adjustable the 3rd side link 5 and frame 4 chain connections of length-adjustable the first side link 1, with measure-alike second connecting rod 6 and the 3rd side link 5 chain connections of first connecting rod 2, with measure-alike the 4th side link 7 and second connecting rod 6 chain connections of the second side link 3, the 4th side link 7 and frame 4 chain connections, the 3rd member 21 is positioned at the chute 22 of first connecting rod 2, the 4th member 31 connects with the second side link 3 by hinge, the extreme length that the first side link 1 and the 3rd side link 5 can reach is 30cm, shortest length is 10cm, first connecting rod 2, the length of second connecting rod 6 and frame 4 is 20cm, the length of the second side link 3 and the 4th side link 7 is 30cm.
Referring to Fig. 1, when only using the first side link 1, first connecting rod 2, the second side link 3 and frame 4, press the length that the first side link 1 straight pin 14 above regulates the first side link 1, when meet stock and quarter butt length sum should≤other two pole lengths sums, when other three bar of Length Ratio of the first side link 1 all in short-term, this teaching aid can be used for demonstrating the principle of work of crank and rocker mechanism, double-crank mechanism.When regulating the length of the first side link 1, make not meet between each bar stock and quarter butt length sum should≤during other two pole lengths sums, this teaching aid can be used for demonstrating the principle of work of double rocker mechanism.This method is used teaching aid to can be used for demonstrating four-bar linkage fundamental type: the principle of work of crank and rocker mechanism, double-crank mechanism and double rocker mechanism and mechanism inversion principle.In like manner, when only using the 3rd side link 5, second connecting rod 6, the 4th side link 7 and frame 4, method is identical.
Referring to Fig. 1, Fig. 2, Fig. 7, when simultaneously, use the first side link 1, first connecting rod 2, the second side link 3, frame 4, the 3rd side link 5, when second connecting rod 6 and the 4th side link 7, regulate the length of the first side link 1 and the 3rd side link 5, make their length identical, rotate the 3rd side link 5 and second connecting rod 6 conllinear, towards the direction contrary with the 3rd side link 5, rotate the first side link 1 and first connecting rod 2 conllinear, at this moment the 3rd side link 5 and the 4th side link 7 are respectively in extreme position, this method teaching aid can be used for demonstrating four-bar linkage extreme position and crank angle between two limit positions.
Referring to Fig. 7, the 3rd member 21 is arranged in the chute 22 of first connecting rod 2, protractile during use, and the 4th member 31 connects with the second side link 3 by hinge, opens 90 degree angles during use.When the 3rd member 21 is overhanging, open while spending for 3 one-tenth 90 with the second side link with the 4th member 31, in rotating the process of the first side link 1, angle between the 3rd member 21 and the 4th member 31 gradually changes, and can be used for demonstrating the force-transfer characteristic of four-bar linkage with this teaching aid.When the first side link 1 and frame 4 conllinear, this teaching aid can be used for demonstrating the mechanism position that four-bar linkage minimum transmission angle occurs.
Referring to Fig. 3, Fig. 4, Fig. 5, length-adjustable the first side link 1, comprises second component 12 with straight pin 14, with the first member 11 of some circular holes 13, and straight pin 14 matches with circular hole 13, and straight pin 14 lower ends are connected with spring 9.The ingredient of length-adjustable the 3rd side link 5 is identical with the first side link 1.Length-adjustable the first side link 1, has length scale on its first member 11 and second component 12; On the composition member of length-adjustable the 3rd side link 5, there is too scale.While changing bar length, press down straight pin 14, Compress Spring 9, shrinking connecting-rod, is adjusted to suitable length, and straight pin 14 ejects from corresponding circle hole 13, and length is determined.This teaching aid can be used for demonstrating the Grashof's criterion of four-bar linkage.
Referring to Fig. 1, the revolute pair 8 at all hinges place is hollow circular hole, and is surrounded by TR thin rubber material.In hole, insert chalk, make this teaching aid can be used as drawing instrument and use.
The teaching aid of the utility model for two cover four-bar linkages are combined, adopt the form of expansion link, and on rod member with scale, so just can read easily the length of rod member and by regulating the length of rod member to realize various forms of motion, facilitate student to understand the principle of work of four-bar mechanism.In addition, this utility model can also be demonstrated the mechanism position that four-bar linkage extreme position and crank angle between two limit positions and minimum transmission angle occur, makes like this content of courses more directly perceived, and this teaching aid is both economical practicality also.
In figure, 1 is the first side link, and 2 is first connecting rod, 3 is the second side link, and 4 is frame, and 5 is the 3rd side link, 6 is second connecting rod, and 7 is the 4th side link, and 8 is revolute pair, 9 is spring, and 11 is the first member, and 12 is second component, 13 is circular hole, and 14 is straight pin, and 21 is the 3rd member, 22 is chute, and 31 is the 4th member.
Claims (6)
1. a multi-functional four-bar mechanism operating characteristic demonstration teaching aid, it is characterized in that, comprise: the first side link (1), first connecting rod (2), the second side link (3), frame (4), the 3rd side link (5), second connecting rod (6) and the 4th side link (7), described the first side link (1) is two length-adjustable supports that size is identical with structure with the 3rd side link (5), described first connecting rod (2) is two supports that size is identical with structure with second connecting rod (6), described the second side link (3) is two supports that size is identical with structure with the 4th side link (7), one end of one end of described the first side link (1) and first connecting rod (2) is connected through the hinge, one end of the other end of described first connecting rod (2) and the second side link (3) is connected through the hinge, one end of the other end of described the second side link (3) and frame (4) is connected through the hinge, the other end of the other end of described frame (4) and the first side link (1) is connected through the hinge, one end of one end of described the 3rd side link (5) and second connecting rod (6) is connected through the hinge, one end of the other end of described second connecting rod (6) and the 4th side link (7) is connected through the hinge, one end of the other end of described the 4th side link (7) and frame (4) is connected through the hinge, the other end of the other end of described frame (4) and the 3rd side link (5) is connected through the hinge, described first connecting rod (2) is provided with the 3rd member (21), chute 22, described the 3rd member 21 is positioned at chute 22, described the second side link (3) is provided with the 4th member (31), described the 4th member (31) connects with the second side link (3) by hinge.
2. a kind of multi-functional four-bar mechanism operating characteristic demonstration teaching aid according to claim 1, it is characterized in that: described the first side link (1) and the 3rd side link (5) are connected to form by the first member (11) and second component (12) respectively, described the first member (11) is provided with the straight pin being parallel to each other (14) of a plurality of projections, described second component (12) is provided with a plurality of circular holes that are parallel to each other (13), described circular hole (13) matches with the structure of straight pin (14), described straight pin (14) can insert in circular hole (13) length of the first side link (1) is regulated, described straight pin (14) lower end is provided with spring (9), described spring (9) one end connecting cylinder pin (14) lower end, the other end connects second component (12), described spring (9) can promote straight pin (14) card and in circular hole (13) the inside, length to the first side link plays fixation.
3. a kind of multi-functional four-bar mechanism operating characteristic demonstration teaching aid according to claim 1, is characterized in that: described the first member (11) and second component (12) surface are provided with scale, and scale unit is cm.
4. a kind of multi-functional four-bar mechanism operating characteristic demonstration teaching aid according to claim 1, it is characterized in that: in described first connecting rod (2), be provided with chute (22), described the 3rd member (21) is accommodated in chute (22), and described the 3rd member (21) can be interior protruding from chute (22).
5. a kind of multi-functional four-bar mechanism operating characteristic demonstration teaching aid according to claim 1, it is characterized in that: described the 4th member (31) connects with the second side link (3) by hinge, described the 4th member (31) can forward rotation 90 be spent, and from the second side link (3), spins out.
6. a kind of multi-functional four-bar mechanism operating characteristic demonstration teaching aid according to claim 1, it is characterized in that: the revolute pair (8) at described all hinges place is hollow circular hole, and being surrounded by TR thin rubber material, described revolute pair (8) can be loaded onto chalk and use as drawing instrument.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420135349.1U CN203759978U (en) | 2014-03-24 | 2014-03-24 | Multi-functional four-rod mechanism function demonstrating and teaching apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420135349.1U CN203759978U (en) | 2014-03-24 | 2014-03-24 | Multi-functional four-rod mechanism function demonstrating and teaching apparatus |
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| Publication Number | Publication Date |
|---|---|
| CN203759978U true CN203759978U (en) | 2014-08-06 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420135349.1U Expired - Fee Related CN203759978U (en) | 2014-03-24 | 2014-03-24 | Multi-functional four-rod mechanism function demonstrating and teaching apparatus |
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| CN (1) | CN203759978U (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104332103A (en) * | 2014-11-25 | 2015-02-04 | 沈阳建筑大学 | Portable plane mechanism synthesis demonstration teaching tool |
| CN109243283A (en) * | 2018-10-24 | 2019-01-18 | 上海外高桥造船有限公司 | Assembly manipulation operation teaching aid |
| CN109741664A (en) * | 2018-12-29 | 2019-05-10 | 合肥工业大学 | Electro-active material locus of planar 4-bar linkage synthesis experiment platform and its experimental method |
| CN109801550A (en) * | 2019-03-25 | 2019-05-24 | 上海工程技术大学 | A kind of All-in-One double leval jib teaching mould |
| CN111047963A (en) * | 2020-01-06 | 2020-04-21 | 重庆智能机器人研究院 | Plane link mechanism demonstration device |
-
2014
- 2014-03-24 CN CN201420135349.1U patent/CN203759978U/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104332103A (en) * | 2014-11-25 | 2015-02-04 | 沈阳建筑大学 | Portable plane mechanism synthesis demonstration teaching tool |
| CN104332103B (en) * | 2014-11-25 | 2016-08-24 | 沈阳建筑大学 | A kind of Portable plane synthesis of mechanism demonstration teaching aid |
| CN109243283A (en) * | 2018-10-24 | 2019-01-18 | 上海外高桥造船有限公司 | Assembly manipulation operation teaching aid |
| CN109741664A (en) * | 2018-12-29 | 2019-05-10 | 合肥工业大学 | Electro-active material locus of planar 4-bar linkage synthesis experiment platform and its experimental method |
| CN109801550A (en) * | 2019-03-25 | 2019-05-24 | 上海工程技术大学 | A kind of All-in-One double leval jib teaching mould |
| CN109801550B (en) * | 2019-03-25 | 2021-03-26 | 上海工程技术大学 | All-in-one four-connecting-rod teaching mold |
| CN111047963A (en) * | 2020-01-06 | 2020-04-21 | 重庆智能机器人研究院 | Plane link mechanism demonstration device |
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| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140806 Termination date: 20150324 |
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| EXPY | Termination of patent right or utility model |