Changeable four-bar mechanism teaching demonstration system

Abstract

The utility model discloses a changeable four-bar mechanism teaching demonstration system comprising a part library which comprises a pedestal, a rod member 1, a rod member 2, a rod member 3, a rod member 5, a gasket, a connecting pin, a separator plate, a slide block, a pressing plate and a guide plate; and teaching demonstration of the related four-bar mechanism is realized based on part or all of the parts in the part library. The objective of the utility model is to provide a demonstration tool for learning and verifying related knowledge of a four-bar mechanism for a learner when the four-bar mechanism part in mechanical knowledge is learned. The problem of understanding and practicing knowledge by learners is solved, and learning efficiency and cognitive competence are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of teaching aids, and more specifically to a teaching demonstration system of a variable four-bar mechanism. Background Art

[0002] In the teaching process of mechanical majors, the four-bar mechanism is an inescapable topic, and it is also one of the most common mechanisms in mechanisms. It is not easy to understand during the learning process. How to provide a demonstration mechanism system to effectively solve the problems in the learning process has become the research direction of those skilled in the art.

[0003] Currently, the available four-bar mechanism demonstration devices have a single function and can only demonstrate relatively fixed partial functions, and cannot demonstrate the four-bar mechanism and its basic evolved mechanisms. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a teaching demonstration system of a variable four-bar mechanism in order to solve the technical problems existing in the background art.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A teaching demonstration system of a variable four-bar mechanism, comprising: a parts library, and the parts library includes:

[0007] A base, a first rod, a second rod, a third rod, a fifth rod, washers, connecting pins, a partition, a slider, a pressing plate, and a guide plate; the teaching demonstration of relevant four-bar mechanisms is realized based on some or all of the parts in the parts library.

[0008] In some embodiments, the four-bar mechanism is a crank-rocker mechanism, and the parts used for the crank-rocker mechanism are: a base, connecting pins, a first rod and a second rod. Among them, the connecting pins include a first connecting pin, a second connecting pin, a third connecting pin and a fourth connecting pin, the second rod includes a first second rod and a second second rod, the first rod and the first second rod are respectively fixed on the base with the first connecting pin and the fourth connecting pin, and the first rod and the first second rod can rotate around their respective connecting pins; the second connecting pin and the third connecting pin connect the second second rod with the first second rod and the first rod respectively.

[0009] In some embodiments, the four-bar mechanism is a double-crank mechanism, and the parts used for the double-crank mechanism are: a base, a second rod, connecting pins, washers and a third rod. Among them, the second rod includes a first second rod, a second second rod and a third second rod, the connecting pins include a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a fifth connecting pin and a sixth connecting pin, and the washers include a first washer and a second washer;

[0010] Fix the third rod two to the base using the fifth connecting pin. The third rod two can rotate around the fifth connecting pin. Connect the first rod two to the third rod two using the sixth connecting pin. Connect the second rod two to the first rod two using the first connecting pin. Connect rod three to the second rod two using the fourth connecting pin. Connect the other end of rod three to the base using the first washer and the second washer through the second connecting pin and the third connecting pin.

[0011] In some embodiments, the four-bar mechanism is a double-rocker mechanism. The parts used in the double-rocker mechanism are: a base, rod two, rod one, connecting pins, washers, and rod three. Among them, the connecting pins include the first connecting pin, the second connecting pin, the third connecting pin, and the fourth connecting pin.

[0012] Fix rod two to the base using the fourth connecting pin. Rod two can rotate around the fourth connecting pin. Connect rod one to the first rod two using the first connecting pin. Connect rod three to rod one using the second connecting pin. Connect the other end of rod three to the base using 2 washers through the third connecting pin.

[0013] In some embodiments, the four-bar mechanism is a center-crank slider mechanism. The parts used in the center-crank slider mechanism are: a base, a guide plate, a pressure plate, a slider, rod two, connecting pins, washers, and rod one. Among them, the connecting pins include the first connecting pin, the second connecting pin, the third connecting pin, the fourth connecting pin, the fifth connecting pin, the sixth connecting pin, and the seventh connecting pin. The washers include the first washer and the second washer. The guide plate includes: the first guide plate and the second guide plate. The pressure plate includes: the first pressure plate and the second pressure plate.

[0014] Fix the guide plate and the pressure plate to the base through the first connecting pin and the seventh connecting pin. Similarly, fix the second guide plate and the second pressure plate to the base through the second connecting pin and the fourth connecting pin. Place the slider between the two first guide plates and the second guide plate. Install a second washer between rod two and the slider and connect them through the third connecting pin. Fix rod one to the base through the sixth connecting pin, with the position coinciding with the extension line of the slider's sliding trajectory. Add a first washer between the other end of rod one and rod two and connect them through the fifth connecting pin.

[0015] In some embodiments, the four-bar mechanism is an offset-crank slider mechanism. The parts used in the offset-crank slider mechanism are: a base, a guide plate, a pressure plate, a slider, rod two, connecting pins, washers, and rod one. Among them, the guide plate includes: the first guide plate, the second guide plate. The connecting pins include the first connecting pin, the second connecting pin, the third connecting pin, the fourth connecting pin, the fifth connecting pin, the sixth connecting pin, the seventh connecting pin. The pressure plate includes the first pressure plate, the second pressure plate. The washers include the first washer and the second washer.

[0016] The first guide plate and the first pressure plate are fixed to the base through the first connecting pin and the seventh connecting pin. Similarly, the second guide plate and the second pressure plate are fixed to the base through the second connecting pin and the fourth connecting pin. The slider is placed between the first guide plate and the second guide plate. A second washer is installed between rod member 2 and the slider, and they are connected through the third connecting pin. Rod member 1 is fixed to the base through the sixth connecting pin, and its position is staggered with the extension line of the sliding track of the slider. A first washer is added between the other end of rod member 1 and rod member 2, and they are connected through the fifth connecting pin.

[0017] In some embodiments, the four-bar mechanism is a guide bar mechanism, and the parts used in the guide bar mechanism are: a base, a slider, a partition, a rod member 2, a connecting pin, a washer and a rod member 5, wherein the connecting pin includes a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a fifth connecting pin and a sixth connecting pin, the washer includes a first washer, a second washer and a third washer, and the rod member 5 includes a first rod member 5 and a second rod member 5;

[0018] A first washer is installed on the second rod member 5 and fixed to the base through a first connecting pin. The second rod member 5 can rotate around the first connecting pin. Two partitions are sandwiched between the two sliders and fixed through four sixth connecting pins so that the second rod member 5 passes through the gap in the middle. One end of the rod member 2 is connected to the upper slider through a fifth connecting pin, and the other end is connected to the first rod member 5 through a second connecting pin. Two groups of four washers, a second washer and a third washer, are added to one end of the first rod member 5 and fixed to the base through a third connecting pin and a fourth connecting pin. The two connecting pins are fixed to ensure that the first rod member 5 does not move or rotate relative to the original position.

[0019] In some embodiments, the four-bar mechanism is a fixed block mechanism, and the parts used in the fixed block mechanism are: a base, a slider, a guide plate, a partition, a rod member 2, a rod member 1, a connecting pin and a rod member 5, wherein the connecting pins include a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a fifth connecting pin and a sixth connecting pin;

[0020] Two partitions are sandwiched between the two sliders and fixed by four sixth connecting pins, the slider is fixed to the base using the fifth connecting pin, and the rod five passes through the gap in the middle, the guide plate is fixed to the base by the first connecting pin and the fourth connecting pin to ensure that the slider does not rotate, one end of the rod one is connected to the rod five by the third connecting pin, and the other end is connected to the rod two by the second connecting pin, and the other end of the rod two is connected to the top surface of the slider by the fifth connecting pin, the length of the rod one is required to be less than the length of the rod two, and the length of the rod two is less than the length of the rod five.

[0021] In some embodiments, the four-bar mechanism is a rocker mechanism, and the parts used in the rocker mechanism are: a base, a slider, a partition, a connecting pin, a rod member 1 and a rod member 5, wherein the connecting pin includes a first connecting pin, a second connecting pin, a third connecting pin and a fourth connecting pin;

[0022] Fix two partitions between two sliders and fix them with four first connecting pins. Use a second connecting pin to fix the slider on the base, and pass the fifth rod through the middle gap. One end of the first rod is connected to the fifth rod through a fourth connecting pin, and the other end is fixed on the base through a third connecting pin.

[0023] The beneficial effects of the present utility model compared with the prior art are as follows:

[0024] 1. Through dynamic demonstration teaching, it is beneficial for learners to accept, understand and improve their learning interest.

[0025] 2. Thousands of combination forms can effectively verify the authenticity of the judgment method for the type of four-bar mechanism.

[0026] 3. It can effectively improve the hands-on ability and innovative thinking of learners, and enhance the sense of gain of learners.

[0027] 4. By selecting different hole distances of the base plate and the rods for combination, various combination forms of four-bar mechanisms can be obtained, and tens of thousands of connecting rod motion trajectories can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the base of a teaching demonstration system for a versatile four-bar mechanism;

[0029] Figure 2 It is a schematic diagram of the first rod of a teaching demonstration system for a versatile four-bar mechanism;

[0030] Figure 3 It is a schematic diagram of the second rod of a teaching demonstration system for a versatile four-bar mechanism;

[0031] Figure 4 It is a schematic diagram of the third rod of a teaching demonstration system for a versatile four-bar mechanism;

[0032] Figure 5 It is a schematic diagram of the fifth rod of a teaching demonstration system for a versatile four-bar mechanism;

[0033] Figure 6 It is a schematic diagram of the washer of a teaching demonstration system for a versatile four-bar mechanism;

[0034] Figure 7 It is a schematic diagram of the connecting pin of a teaching demonstration system for a versatile four-bar mechanism;

[0035] Figure 8 It is a schematic diagram of the partition of a teaching demonstration system for a versatile four-bar mechanism;

[0036] Figure 9 It is a schematic diagram of the slider of a teaching demonstration system for a versatile four-bar mechanism;

[0037] Figure 10 Schematic diagram of the pressing plate of a variable four-bar mechanism teaching demonstration system;

[0038] Figure 11 Schematic diagram of the guide plate of a variable four-bar mechanism teaching demonstration system;

[0039] Figure 12 Schematic diagram of a crank-rocker mechanism;

[0040] Figure 13 Schematic diagram of a double-crank mechanism;

[0041] Figure 14 Schematic diagram of a double-rocker mechanism;

[0042] Figure 15 Schematic diagram of a direct-acting crank-slider mechanism;

[0043] Figure 16 Schematic diagram of an offset crank-slider mechanism;

[0044] Figure 17 Schematic diagram of a swinging guide bar;

[0045] Figure 18 Schematic diagram of a rotating guide bar;

[0046] Figure 19 Schematic diagram of a fixed-block mechanism;

[0047] Figure 20 Schematic diagram of a swinging-block mechanism. Detailed implementation manners

[0048] To make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the preferred embodiments of the present application will be described in more detail below with reference to the accompanying drawings in the preferred embodiments of the present application. In the drawings, the same or similar reference numerals denote the same or similar components or components with the same or similar functions from beginning to end. The described embodiments are some but not all of the embodiments of the present application. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present application and should not be construed as limiting the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts fall within the scope of protection of the present application.

[0049] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0050] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, or an indirect connection through an intermediate medium, and can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0051] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "front end", "rear end", "both ends", "one end", "the other end", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance.

[0052] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0053] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship of the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0054] The following will be combined with Figures 1 - 20 , and a teaching demonstration system for a versatile four-bar mechanism involved in the embodiments of the present application will be described in detail. It should be noted that the following embodiments are only used to explain the present application and do not constitute a limitation to the present application.

[0055] Embodiment:

[0056] A teaching demonstration system for a variable four-bar mechanism, comprising: a parts library, the parts library including: a base, a first rod, a second rod, a third rod, a fifth rod, washers, connecting pins, partitions, sliders, pressing plates, guide plates; realizing the teaching demonstration of relevant four-bar mechanisms based on some or all of the parts in the parts library.

[0057] See Figure 1 , Base: The diameter of the middle matrix holes is φ6, the hole pitch is 50mm, all hole openings are chamfered C1, and the fillets at the four corners are R5. The plate thickness is 10mm

[0058] The front diameter of the six peripheral holes is φ10mm, the depth is 5mm, and the bottom hole diameter is φ5mm. Used to install a strong magnet to magnetically attract the bottom plate to the blackboard.

[0059] See Figure 2 , First rod: The hole pitch at both ends is 100mm, and the hole pitch from the left end to the right end is 15mm, 40mm, 20mm, 25mm in sequence. The hole diameter is φ6, the width of the rod is 16mm, the rod thickness is 5mm, and all hole openings are chamfered C1. ( Figure 2 )

[0060] See Figure 3 , Second rod: The hole pitch at both ends is 200mm, and the hole pitch from the left end to the right end is 17mm, 29mm, 42mm, 32mm, 23mm, 26mm, 31mm in sequence. The hole diameter is φ6, the width of the rod is 16mm, the rod thickness is 5mm, and all hole openings are chamfered C1. ( Figure 3 )

[0061] See Figure 4 , Third rod: The hole pitch at both ends is 300mm, and the hole pitch from the left end to the right end is 50mm, 40mm, 60mm, 45mm, 50mm, 55mm in sequence. The hole diameter is φ6, the width of the rod is 16mm, the rod thickness is 5mm, and all hole openings are chamfered C1. ( Figure 4 )

[0062] See Figure 5 , Fifth rod: The hole pitch at both ends is 500mm, and the hole pitch from the left end to the right end is 50mm, 40mm, 60mm, 45mm, 55mm, 70mm, 75mm, 55mm, 50mm in sequence. The hole diameter is φ6, the width of the rod is 16mm, the rod thickness is 5mm, and all hole openings are chamfered C1. ( Figure 5 )

[0063] See Figure 6 , Washers: The outer diameter is φ16mm, the hole diameter is φ6, the thickness is 5mm, and the hole opening is chamfered C1. ( Figure 6 )

[0064] See Figure 7, Connecting pin: The main body diameter is φ6mm, with a convex platform of R0.3mm at each end. Both ends are hollow and have a 1mm slot. The slots at both ends are staggered by 90°. The length specifications are 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm.( Figure 7 )

[0065] See Figure 8 , Partition board: The length is 50mm, the board width is 17mm, the board thickness is 5mm, the chamfer size is C5mm, the fillet is R5, the center distance of the row of holes from the chamfered edge is 9mm, the distance between two holes is 34mm, the diameter is φ6, and the hole chamfer is C1.( Figure 8 )

[0066] See Figure 9 , Slide block: The outer shape is 50mm×50mm, the thickness is 5mm, the chamfers around are R5mm, there is a hole in the exact middle, and four holes around. The distance between the four holes is 34mm, the hole diameter is φ6mm, and the hole chamfer is C1.( Figure 9 )

[0067] See Figure 10 , Pressure plate: The length is 420mm, the board width is 50mm, the board thickness is 5mm, the center distance of the row of holes from the chamfered edge is 30mm, the chamfer size for the narrow side is 15, the long side is 20mm, and the other two corners are filleted with R5. The hole pitch of the row of holes is 50mm, the diameter is φ6, and the hole chamfer is C1.( Figure 10 )

[0068] See Figure 11 , Guide plate: The length is 420mm, the board width is 50mm, the board thickness is 5mm, the center distance of the row of holes from the long side is 25mm, the chamfers around are R5, the hole pitch of the row of holes is 50mm, the diameter is φ6, and the hole chamfer is C1.( Figure 11 )

[0069] Example 1

[0070] See Figure 12 , The four-bar mechanism is a crank-rocker mechanism. The parts used in the crank-rocker mechanism are: base, connecting pin, link one, and link two. Among them, the connecting pin includes the first connecting pin, the second connecting pin, the third connecting pin, and the fourth connecting pin. Link two includes the first link two and the second link two. Link one and the first link two are respectively fixed on the base 1 with the first connecting pin and the fourth connecting pin, and link one and the first link two can rotate around their respective connecting pins; the second connecting pin 4 and the third connecting pin 6 connect the second link two with the first link two and link one respectively.

[0071] When link one rotates around the fourth connecting pin, it drives the first link two to swing reciprocally through the second link two; that is, a crank-rocker mechanism is formed.

[0072] Example 2

[0073] See Figure 13 The four-bar mechanism is a double-crank mechanism. The parts used in the double-crank mechanism are: a base, a second rod, a connecting pin, a washer, and a third rod. Among them, the second rod includes a first second rod, a second second rod, and a third second rod. The connecting pins include a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a fifth connecting pin, and a sixth connecting pin. The washers include a first washer and a second washer;

[0074] Fix the third second rod 13 to the base 1 using the fifth connecting pin 12. The third second rod 13 can rotate around the fifth connecting pin 12. Connect the first second rod 2 to the third second rod 13 using the sixth connecting pin 14. Connect the second second rod 4 to the first second rod 2 using the first connecting pin 3. Connect the third rod 10 to the second second rod 4 using the fourth connecting pin 11. Connect the other end of the third rod 10 to the base 1 using the first washer and the second washer through the second connecting pin 5 and the third connecting pin 7.

[0075] When the third second rod 13 rotates around the fifth connecting pin 12, the second second rod 4 will also rotate accordingly; thus forming a double-crank mechanism.

[0076] Embodiment 3

[0077] See Figure 14 The four-bar mechanism is a double-rocker mechanism. The parts used in the double-rocker mechanism are: a base, a second rod, a first rod, a connecting pin, a washer, and a third rod. Among them, the connecting pins include a first connecting pin, a second connecting pin, a third connecting pin, and a fourth connecting pin;

[0078] Fix the second rod 2 to the base 1 using the fourth connecting pin 9. The second rod 2 can rotate around the fourth connecting pin 9. Connect the first rod 4 to the first second rod 2 using the first connecting pin 3. Connect the third rod 6 to the first rod 4 using the second connecting pin 5. Connect the other end of the third rod 6 to the base 1 using 2 washers 7 through the third connecting pin 8.

[0079] Neither the third rod 6 nor the first second rod 2 can achieve a full rotation, but can only swing within a certain range; thus forming a double-rocker mechanism.

[0080] Embodiment 4

[0081] See Figure 15 The four-bar mechanism is a center-crank slider mechanism. The parts used in the center-crank slider mechanism are: a base, a guide plate, a pressing plate, a slider, a second rod, a connecting pin, a washer, and a first rod. Among them, the connecting pins include a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a fifth connecting pin, a sixth connecting pin, and a seventh connecting pin. The washers include a first washer and a second washer; The guide plate includes: a first guide plate 2 and a second guide plate 5. The pressing plate includes: a first pressing plate 4 and a second pressing plate 7;

[0082] The guide plate 2 and the pressure plate 4 are fixed on the base 1 through the first connecting pin 3 and the seventh connecting pin 16. Similarly, the second guide plate 5 and the second pressure plate 7 are fixed on the base 1 through the second connecting pin 6 and the fourth connecting pin 11. The slider 8 is placed between the two first guide plates 2 and the second guide plate 5. A second washer 17 is installed between the rod two 10 and the slider 8 and is connected through the third connecting pin 9. The rod one 14 is fixed on the base 1 through the sixth connecting pin 15, and its position coincides with the extension line of the sliding track of the slider. A first washer 13 is added between the other end of the rod one 14 and the rod two 10, and they are connected through the fifth connecting pin 12.

[0083] During operation, the rod one 14 rotates around the sixth connecting pin 15, and the slider 8 moves linearly in the chute. That is, a crank-slider mechanism is formed. Since the extension line of the moving track line of the slider (the central track line of the third connecting pin 9) just passes through the center of rotation of the crank (the center of the sixth connecting pin 15), this crank-slider mechanism is a center-crank slider mechanism.

[0084] Embodiment 5

[0085] See Figure 16 , the four-bar mechanism is an offset crank-slider mechanism. The parts used in the offset crank-slider mechanism are: a base, guide plates, pressure plates, sliders, rod two, connecting pins, washers, and rod one. Among them, the guide plates include: the first guide plate 2 and the second guide plate 5, the connecting pins include the first connecting pin 3, the second connecting pin 6, the third connecting pin 9, the fourth connecting pin 11, the fifth connecting pin 12, the sixth connecting pin 15, and the seventh connecting pin 16, the pressure plates include the first pressure plate 4 and the second pressure plate 7, and the washers include the first washer 13 and the second washer 17;

[0086] The first guide plate 2 and the first pressure plate 4 are fixed on the base 1 through the first connecting pin 3 and the seventh connecting pin 16. Similarly, the second guide plate 5 and the second pressure plate 7 are fixed on the base 1 through the second connecting pin 6 and the fourth connecting pin 11. The slider 8 is placed between the two guide plates, the first guide plate 2 and the second guide plate 5. A second washer 17 is installed between the rod two 10 and the slider 8 and is connected through the third connecting pin 9. The rod one 14 is fixed on the base 1 through the sixth connecting pin 15, and its position is offset from the extension line of the sliding track of the slider. A first washer 13 is added between the other end of the rod one 14 and the rod two 10, and they are connected through the fifth connecting pin 12.

[0087] During operation, the rod one 14 rotates around the sixth connecting pin 15, and the slider 8 moves linearly in the chute. That is, a crank-slider mechanism is formed. Since the extension line of the moving track line of the slider (the central track line of the third connecting pin 9) is offset from the center of rotation of the crank (the center of the sixth connecting pin 15), this crank-slider mechanism is an offset crank-slider mechanism.

[0088] Example 6

[0089] Refer to Figure 17 , the four-bar mechanism is a crank-rocker mechanism, and the parts used in the crank-rocker mechanism are: base, slider, partition, rod two, connecting pin, washer and rod five. Among them, the connecting pins include the first connecting pin 3, the second connecting pin 5, the third connecting pin 6, the fourth connecting pin 7, the fifth connecting pin 11, and the sixth connecting pin 13. The washers include the first washer 2, the second washer 8, and the third washer 9. The rod five includes the first rod five 4 and the second rod five 15;

[0090] Install the first washer 2 on the second rod five 15 and fix it on the base 1 through the first connecting pin 3. The second rod five 15 can rotate around the first connecting pin 3. Two partitions 12 are sandwiched between two sliders 10 and fixed through four sixth connecting pins 13, so that the second rod five 15 passes through the middle gap. One end of the rod two 14 is connected to the upper slider through the fifth connecting pin 11, and the other end is connected to the first rod five 4 through the second connecting pin 5. Two groups of four washers each, the second washer 8 and the third washer 9, are added to one end of the first rod five 4 and fixed on the base 1 through the third connecting pin 6 and the fourth connecting pin 7. The fixation of the two connecting pins ensures that the first rod five has no relative position movement and rotation.

[0091] When the rod two 14 rotates around the second connecting pin 5, it drives the second rod five 15 to swing (the distance between the second connecting pin 5 and the first connecting pin 3 is greater than the distance between the second connecting pin 5 and the fifth connecting pin 11, and the second rod five 15 cannot rotate continuously for a full circle and can only swing within a certain angle range), which is called a swinging crank-rocker mechanism. As Figure 17 .

[0092] When the second connecting pin 5 is in Figure 18 position, the distance between the second connecting pin 5 and the first connecting pin 3 is less than the distance between the second connecting pin 5 and the fifth connecting pin 11. The second rod five 15 can rotate continuously for a full circle under the drive of the rod two 14, which is called a rotating crank-rocker mechanism.

[0093] Example 7

[0094] Refer to Figure 19 , the four-bar mechanism is a fixed-block mechanism, and the parts used in the fixed-block mechanism are: base, slider, guide plate, partition, rod two, rod one, connecting pin and rod five. Among them, the connecting pins include the first connecting pin 3, the second connecting pin 5, the third connecting pin 7, the fourth connecting pin 8, the fifth connecting pin 11, and the sixth connecting pin 13;

[0095] Two sliders 10 are sandwiched between two partition plates 12 and fixed by four sixth connecting pins 13. The sliders are fixed on the base 1 using fifth connecting pins 11, and the rod five 4 is passed through the middle gap. The guide plate 2 is fixed on the base 1 by the first connecting pin 3 and the fourth connecting pin 8 to ensure that the sliders do not rotate. One end of the rod one 6 is connected to the rod five 4 through the third connecting pin 7, and the other end is connected to the rod two 9 through the second connecting pin 5. The other end of the rod two 9 is connected to the top surface of the slider through the fifth connecting pin 11. The length of the rod one 6 is required to be less than the length of the rod two 9, and the length of the rod two 9 is less than the length of the rod five 4.

[0096] When the rod one 6 rotates around the third connecting pin 7, the rod two 9 will swing accordingly, and the rod five 4 will move along the gap in the middle of the slider. The slider remains stationary throughout the entire working process, that is, a fixed-block mechanism is formed.

[0097] Embodiment 8

[0098] See Figure 20 , the four-bar mechanism is a swinging-block mechanism, and the parts used in the swinging-block mechanism are: a base, a slider, a partition plate, a connecting pin, a rod one, and a rod five. Among them, the connecting pins include a first connecting pin 3, a second connecting pin 4, a third connecting pin 7, and a fourth connecting pin 9;

[0099] Two sliders 5 are sandwiched between two partition plates 6 and fixed by four first connecting pins 3. The sliders are fixed on the base 1 using the second connecting pin 4, and the rod five 2 is passed through the middle gap. One end of the rod one 8 is connected to the rod five 2 through the fourth connecting pin 9, and the other end is fixed on the base 1 through the third connecting pin 7.

[0100] When the rod one 8 rotates around the third connecting pin 7, it drives the rod five 2 to move and swing in the slider groove, and the swing of the rod five 2 drives the swing of the slider, that is, a fixed-block mechanism is formed.

[0101] The purpose of the present invention is to provide a demonstration tool for learners to learn and verify the relevant knowledge of the four-bar mechanism when learning the four-bar mechanism part of mechanical knowledge. It solves the problems of learners' understanding and practice of knowledge, and improves learning efficiency and cognitive ability. This demonstration system can completely demonstrate the four-bar mechanisms (crank-rocker mechanism, double-crank mechanism, double-rocker mechanism) and common evolved mechanisms (crank-slider mechanism, fixed-block mechanism, swinging-block mechanism, oscillating guide bar, rotating guide bar), as well as the understanding of dead points and quick-return characteristics.

[0102] Rods of different lengths are selected and paired with different hole pitches, expanding the scope of use of the rods. With equally spaced array holes as the base plate, the fixation problem during the rod demonstration process is effectively solved. Through a number of washers, the problem of movement interference during the combination process can be effectively solved. Connecting pins of different specifications provide the necessary support for the composition of the four-bar mechanism. Strong magnets at the four corners of the base plate can adsorb the base plate on blackboards, whiteboards, etc. for learners to watch or discuss, providing more effective visibility for learners.

[0103] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A versatile four-bar mechanism teaching demonstration system, characterized in that: include: A parts library, the parts library comprising: Base, rod one, rod two, rod three, rod five, washer, connecting pin, partition, slider, pressure plate, guide plate; based on part or all of the parts in the parts library, a teaching demonstration of the relevant four-bar mechanism is realized.

2. The teaching demonstration system of the versatile four-bar mechanism according to claim 1 is characterized in that: The four-bar mechanism is a crank-rocker mechanism, and the parts used in the crank-rocker mechanism are: a base, a connecting pin, a rod member 1 and a rod member 2, wherein the connecting pin includes a first connecting pin, a second connecting pin, a third connecting pin and a fourth connecting pin, and the rod member 2 includes a first rod member 2 and a second rod member 2, the rod member 1 and the first rod member 2 are fixed to the base with the first connecting pin and the fourth connecting pin respectively, and the rod member 1 and the first rod member 2 can rotate around their respective connecting pins; the second connecting pin and the third connecting pin connect the second rod member 2 with the first rod member 2 and the rod member 1 respectively.

3. The teaching demonstration system of the versatile four-bar mechanism according to claim 1 is characterized in that: The four-bar mechanism is a double crank mechanism, and the parts used in the double crank mechanism are: a base, a rod member 2, a connecting pin, a washer and a rod member 3, wherein the rod member 2 includes a first rod member 2, a second rod member 2 and a third rod member 2, the connecting pin includes a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a fifth connecting pin and a sixth connecting pin, and the washer includes a first washer and a second washer; The third rod 2 is fixed to the base using the fifth connecting pin, the third rod 2 can rotate around the fifth connecting pin, the first rod 2 is connected to the third rod 2 using the sixth connecting pin, the second rod 2 is connected to the first rod 2 using the first connecting pin, the rod 3 is connected to the second rod 2 using the fourth connecting pin, and the other end of the rod 3 is connected to the base through the second connecting pin and the third connecting pin using the first washer and the second washer.

4. The teaching demonstration system of the versatile four-bar mechanism according to claim 1 is characterized in that: The four-bar mechanism is a double rocker mechanism, and the parts used in the double rocker mechanism are: a base, a second rod, a first rod, a connecting pin, a washer and a third rod, wherein the connecting pin includes a first connecting pin, a second connecting pin, a third connecting pin and a fourth connecting pin; The rod 2 is fixed to the base using the fourth connecting pin. The rod 2 can rotate around the fourth connecting pin. The rod 1 is connected to the first rod 2 using the first connecting pin. The rod 3 is connected to the rod 1 using the second connecting pin. The other end of the rod 3 is connected to the base through the third connecting pin using 2 washers.

5. The teaching demonstration system of the versatile four-bar mechanism according to claim 1 is characterized in that: The four-bar mechanism is a centrifugal crank slider mechanism, and the parts used in the centrifugal crank slider mechanism are: a base, a guide plate, a pressure plate, a slider, a rod member 2, a connecting pin, a washer and a rod member 1, wherein the connecting pin includes a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a fifth connecting pin, a sixth connecting pin and a seventh connecting pin, and the washer includes a first washer and a second washer; the guide plate includes: a first guide plate and a second guide plate, and the pressure plate includes: a first pressure plate and a second pressure plate; The guide plate and the pressure plate are fixed to the base through the first connecting pin and the seventh connecting pin. Similarly, the second guide plate and the second pressure plate are fixed to the base through the second connecting pin and the fourth connecting pin. The slider is placed between the two first guide plates and the second guide plates. A second washer is installed between the rod 2 and the slider, and they are connected through the third connecting pin. The rod 1 is fixed to the base through the sixth connecting pin, and its position coincides with the extension line of the sliding track of the slider. A first washer is added between the other end of the rod 1 and the rod 2, and they are connected through the fifth connecting pin.

6. The teaching demonstration system of the versatile four-bar mechanism according to claim 1, characterized in that: The four-bar mechanism is an offset crank slider mechanism, and the parts used in the offset crank slider mechanism are: a base, a guide plate, a pressure plate, a slider, a rod member 2, a connecting pin, a washer and a rod member 1, wherein the guide plate includes: a first guide plate and a second guide plate, the connecting pin includes a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a fifth connecting pin, a sixth connecting pin and a seventh connecting pin, the pressure plate includes a first pressure plate and a second pressure plate, and the washer includes a first washer and a second washer; The first guide plate and the first pressure plate are fixed to the base through the first connecting pin and the seventh connecting pin. Similarly, the second guide plate and the second pressure plate are fixed to the base through the second connecting pin and the fourth connecting pin. The slider is placed between the first guide plate and the second guide plate. A second washer is installed between rod member 2 and the slider, and they are connected through the third connecting pin. Rod member 1 is fixed to the base through the sixth connecting pin, and its position is staggered with the extension line of the sliding track of the slider. A first washer is added between the other end of rod member 1 and rod member 2, and they are connected through the fifth connecting pin.

7. The teaching demonstration system of the versatile four-bar mechanism according to claim 1 is characterized in that: The four-bar mechanism is a guide bar mechanism, and the parts used in the guide bar mechanism are: a base, a slider, a partition, a rod member 2, a connecting pin, a washer and a rod member 5, wherein the connecting pin includes a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a fifth connecting pin and a sixth connecting pin, the washer includes a first washer, a second washer and a third washer, and the rod member 5 includes a first rod member 5 and a second rod member 5; A first washer is installed on the second rod member 5 and fixed to the base through a first connecting pin. The second rod member 5 can rotate around the first connecting pin. Two partitions are sandwiched between the two sliders and fixed through four sixth connecting pins so that the second rod member 5 passes through the gap in the middle. One end of the rod member 2 is connected to the upper slider through a fifth connecting pin, and the other end is connected to the first rod member 5 through a second connecting pin. Two groups of four washers, a second washer and a third washer, are added to one end of the first rod member 5 and fixed to the base through a third connecting pin and a fourth connecting pin. The two connecting pins are fixed to ensure that the first rod member 5 does not move or rotate relative to the original position.

8. The teaching demonstration system of the versatile four-bar mechanism according to claim 1 is characterized in that: The four-bar mechanism is a fixed block mechanism, and the parts used in the fixed block mechanism are: a base, a slider, a guide plate, a partition, a rod member 2, a rod member 1, a connecting pin and a rod member 5, wherein the connecting pins include a first connecting pin, a second connecting pin, a third connecting pin, a fourth connecting pin, a fifth connecting pin and a sixth connecting pin; Two partitions are sandwiched between the two sliders and fixed by four sixth connecting pins, the slider is fixed to the base using the fifth connecting pin, and the rod five passes through the gap in the middle, the guide plate is fixed to the base by the first connecting pin and the fourth connecting pin to ensure that the slider does not rotate, one end of the rod one is connected to the rod five by the third connecting pin, and the other end is connected to the rod two by the second connecting pin, and the other end of the rod two is connected to the top surface of the slider by the fifth connecting pin, the length of the rod one is required to be less than the length of the rod two, and the length of the rod two is less than the length of the rod five.

9. The teaching demonstration system of the versatile four-bar mechanism according to claim 1, characterized in that: The four-bar mechanism is a rocker mechanism, and the parts used in the rocker mechanism are: a base, a slider, a partition, a connecting pin, a rod member 1 and a rod member 5, wherein the connecting pins include a first connecting pin, a second connecting pin, a third connecting pin and a fourth connecting pin; Two partitions are sandwiched between the two sliders and fixed by four first connecting pins, the sliders are fixed to the base using second connecting pins, and rod member five passes through the gap in the middle, one end of rod member one is connected to rod member five by a fourth connecting pin, and the other end is fixed to the base by a third connecting pin.

Images