CN217113587U - Mechanics instant center demonstration teaching aid - Google Patents

Abstract

The utility model provides a mechanical instant center demonstration teaching aid, which comprises a base, a first rod piece, a second rod piece, a third rod piece and a fourth rod piece; the first rod piece is relatively fixed with the base; the first rod piece is arranged along the length extending direction of the base; one end of the second rod piece is hinged with the first rod piece with a position locking function, the other end of the second rod piece extends outwards in the direction far away from the first rod piece, and the second rod piece and the first rod piece are arranged at an included angle; one end of the third rod piece is hinged with the second rod piece with a position locking function, and the other end of the third rod piece extends towards the direction far away from the second rod piece; one end of the fourth rod piece is hinged with the first rod piece with a position locking function, and the other end of the fourth rod piece extends towards the direction far away from the first rod piece; the third rod piece is also hinged with the fourth rod piece.

Description

Mechanics instant center demonstration teaching aid

Technical Field

The utility model relates to a teaching demonstration instrument technical field especially relates to a mechanics instantaneous center demonstration teaching aid.

Background

When the rigid body moves in a plane, a point with zero instantaneous speed connected with the rigid body can be always found, and the point is an instant center. The instantaneous center comprises an absolute instantaneous center and a relative instantaneous center, the instantaneous center with the speed equal to zero is the absolute instantaneous center, and the instantaneous center with the speed not equal to zero is the relative instantaneous center. If the rigid body is a four-bar mechanism, the number of instantaneous centers is related to the number of bar pieces, the instantaneous centers between the components directly forming the kinematic pair can be directly observed and determined, and the instantaneous centers between the components not directly forming the kinematic pair are determined by the three-center theorem. The instantaneous center position of the kinematic pair which is not directly formed is not visual enough, the motion track, namely the polar trace, is not visual enough, and a special demonstration teaching aid is needed for teaching demonstration, so that audiences can understand and master the theoretical concepts conveniently. The existing instant center demonstration teaching aid is inconvenient to adjust and single in structure, is inconvenient to use, and influences the demonstration effect.

Therefore, it is necessary to provide a teaching aid for demonstrating the instant center of mechanics, which is flexible in adjustment and simple in use.

SUMMERY OF THE UTILITY MODEL

In view of this, the utility model provides a can demonstrate the whole instantaneous center of mechanics of four-bar member mechanism and the demonstration teaching aid of the instantaneous center of mechanics of its utmost point trace directly perceived.

The technical scheme of the utility model is realized like this: the utility model provides a mechanical instant center demonstration teaching aid, which comprises a base (100), a first rod piece (1), a second rod piece (2), a third rod piece (3) and a fourth rod piece (4);

the first rod piece (1) is relatively fixed with the base (100); the first rod piece (1) is arranged along the length extending direction of the base (100);

one end of the second rod piece (2) is hinged with the first rod piece with a position locking function, and the other end of the second rod piece (2) extends outwards in the direction far away from the first rod piece (1); the second rod piece (2) and the first rod piece (1) form an included angle;

one end of the third rod piece (3) is hinged with the second rod piece (2) with a position locking function, and the other end of the third rod piece (3) extends towards the direction far away from the second rod piece (2);

one end of the fourth rod piece (4) is hinged with the first rod piece (1) with a position locking function, and the other end of the fourth rod piece (4) extends towards the direction far away from the first rod piece (1); the third rod piece (3) is also hinged with the fourth rod piece (4).

On the basis of the above technical scheme, preferably, a clamping groove (200) linearly arranged along the length extension direction of the first rod piece (1), the second rod piece (2), the third rod piece (3) or the fourth rod piece (4) is arranged on the first rod piece, the second rod piece, the third rod piece (3) or the fourth rod piece, a clamping piece (300) is arranged in the clamping groove (200), and the clamping piece (300) is hinged or slidably connected with the rod piece connected with the clamping piece.

Preferably, the clamping groove (200) comprises a plurality of equal-diameter parts (201) and reducing parts (202); the constant diameter parts (201) and the variable diameter parts (202) are arranged in a staggered manner; the diameter of the constant diameter part (201) is larger than that of the variable diameter part (202).

Further preferably, the clamping member (300) comprises a sleeve section (301) and a transition section (302), wherein the sleeve section (301) is fixedly connected with the transition section (302); the transition section (302) is sleeved with a locking part (303), and the locking part (303) is fixedly connected with the transition section (302); the transition section (302) has a profile similar to the shape of the card slot (200).

Preferably, the radial cross section profile of the transition section (302) is a rounded rectangle, the arc-shaped end face of the transition section (302) is abutted against the equal-diameter part (201) of the clamping groove (200), and the distance between the non-arc-shaped end faces of the transition section (302) is adapted to the width of the variable-diameter part (202).

Preferably, the device further comprises a spacing assembly (5), wherein the spacing assembly (5) is arranged between the first rod and the base (100); one end of the spacing component (5) is detachably connected with the base (100), and the other end of the spacing component (5) is detachably connected with the sleeve section (301) of the clamping piece (300) on the first rod piece.

Further preferably, a painting brush (6) is further arranged on the sleeve section (301) of the clamping piece (300) arranged on the non-first rod piece (1), and the painting brush (6) is detachably connected with the sleeve section (301).

On the basis of the above technical solutions, preferably, the lengths of the first rod (1), the second rod (2), the third rod (3) or the fourth rod (4) are completely the same.

In addition to the above technical solution, preferably, the first bar (1), the second bar (2), the third bar (3) or the fourth bar (4) is made of a thin plate-shaped material, and colors of the bars are different from each other.

The utility model provides a pair of mechanics instant center demonstration teaching aid for prior art, has following beneficial effect:

(1) according to the scheme, the fixed rod piece and the movable rod piece are combined, so that the mutual position relation of a plurality of absolute instantaneous centers and relative instantaneous centers of the rod piece mechanism is clearly shown, and the track of each instantaneous center can be shown by rotating each rod piece through a hinged point;

(2) the clamping piece can be similar to the clamping groove in shape at different parts, and can be hinged or slidably connected with the clamping groove when rotated at different positions, so that the function of rotation or position adjustment is realized; the application range of the demonstration teaching aid is widened, and more combined structure forms of the middle and four connecting rods are displayed;

(3) the rod pieces of all colors are combined with the base, the spacing assembly and the painting brush, so that the motion relation between the centrode of the instantaneous center and the rod pieces can be better displayed, and the teaching demonstration effect is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a perspective view of a mechanical instant center demonstration teaching aid of the present invention;

FIG. 2 is a front view of the combination status of the rods, the interval combination and the painting brush of the instant mechanics demonstration teaching aid of the present invention;

FIG. 3 is a rear view showing the combination status of the rods, the interval combination and the painting brush of the instant mechanics center demonstration teaching aid of the present invention;

FIG. 4 is a perspective view of each member of a mechanical instant center demonstration teaching aid of the present invention;

FIG. 5 is a front view of each member of the instant mechanics center demonstration teaching aid of the present invention;

FIG. 6 is a perspective view of a locking part of the instant mechanics center demonstration teaching aid of the present invention;

FIG. 7 is a partial sectional top view and an A-A view of the locking part of the instant mechanics center demonstration teaching aid of the present invention;

fig. 8 is a perspective view of another combination state of each member, interval combination and painting brush of the instant mechanics center demonstration teaching aid of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work all belong to the protection scope of the present invention.

As an embodiment of the present solution, as shown in fig. 1-4 and fig. 8, the utility model provides a mechanical instant center demonstration teaching aid, which comprises a base 100, a first rod 1, a second rod 2, a third rod 3, a fourth rod 4, etc.;

the first rod 1 is fixed relative to the base 100; the first pin 1 is disposed along the length extension direction of the chassis 100; the end of the first rod 1 has a first end 11 and a second end 12 opposite to each other; the first bar 1 is fixed. The first pin 1 and the base 100 may be spaced apart.

One end of the second rod piece 2 is hinged with the first end 11 of the first rod piece 1, and the other end of the second rod piece 2 extends outwards in the direction far away from the first rod piece 1; the second rod 2 and the first rod 1 are arranged at an included angle.

One end of the third rod 3 is hinged with the non-end part of the second rod 2, and the other end of the third rod 3 extends towards the direction far away from the second rod 2; the third bar 3 is also directed in the direction of the second end 12 of the first bar 1.

One end of the fourth rod 4 is hinged with the non-end position of the first rod 1, and the other end of the fourth rod 4 extends towards the direction far away from the first rod 1; the third bar 3 is also articulated to the fourth bar 4. The area enclosed by the first rod 1, the second rod 4, the third rod 3 and the fourth rod 4 is similar to a four-rod mechanism. As shown in fig. 8, the hinge point of the second rod 2 and the first end 11 of the first rod 1 is B, and the hinge point of the first rod 1 and the fourth rod is C; the hinge point of the first rod piece 1 and the third rod piece is G, and the hinge point of the third rod piece and the third rod piece is D; the hinge point of the second rod piece and the third rod piece is E; the intersection point of the extension line direction of the fourth rod piece 4 and the second rod piece 2 is F; the line segments BE, ED, DC, and BC form a four-bar linkage whose vertices, i.e., B, C, D and E, are absolute instant centers. Point F is on the intersection point of line segment BE and the extension line of line segment CD, point G is on the intersection point of line segment ED and line segment BC, and points F and G are relative instant centers. Because each member is articulated each other, change the position of pin joint, can each instant heart of audio-visual seeing. In this embodiment, the first rod 1 is hinged to the end of the second rod 2, the end of the third rod is hinged to the non-end position of the second rod 2, and the fourth rod is hinged to the non-end position of the first rod, which is a special relative position relationship of the rods. During actual use, the hinging parts of the adjacent rod pieces may need to be further adjusted, so that more free and flexible instant demonstration is realized.

Therefore, as a further improvement of the above embodiment, as shown in fig. 3 to 7, in order to facilitate adjustment of the relative position relationship of the rods, a slot 200 linearly arranged along the length extension direction of the first rod 1, the second rod 2, the third rod 3 or the fourth rod 4 is provided, a clip 300 is provided in the slot 200, and each clip 300 is hinged or slidably connected to the corresponding rod. The clamping groove 200 and the clamping member 300 can fix the relative positions of two adjacent rod pieces. Any two adjacent rods are hinged with a position locking function, even though the third rod 3 and the fourth rod 4 can also be hinged with a position locking function.

The clamping groove 200 comprises a plurality of equal-diameter parts 201 and reducing parts 202; the constant diameter parts 201 and the variable diameter parts 202 are arranged in a staggered manner; the diameter of the constant diameter portion 201 is larger than that of the variable diameter portion 202. As can be seen from the figure, the constant diameter portion 201 is similar to a semi-circular arc structure, and the width of the variable diameter portion 202 is obviously different from that of a rectangular structure.

Correspondingly, the clamping member 300 comprises a sleeve section 301 and a transition section 302, and the sleeve section 301 is fixedly connected with the transition section 302; the transition section 302 is sleeved with a locking part 303, and the locking part 303 is fixedly connected with the transition section 302; the transition section 302 is contoured to resemble the shape of the card slot 200. As can be seen from the figure, the outer diameters of the sleeve section 301 and the locking portion 303 are both larger than the equal-diameter portion 201, and the locking portion 303 is screwed to press the locking portion 303 on the surface of the corresponding rod member, so as to prevent the clamping member 300 from rotating to cause the position thereof to slide in the clamping groove 200. The sleeve section and the transition section may be threaded.

As shown in fig. 6 and 7, the radial cross-sectional profile of the transition section 302 is a rounded rectangle, the arc-shaped end surface of the transition section 302 abuts against the equal-diameter portion 201 of the slot 200, and the distance between the non-arc-shaped end surfaces of the transition section 302 is adapted to the width of the variable-diameter portion 202. It can be seen that the transition section has a pair of arcuate end surfaces and a pair of flat surfaces. The shape of the arc end face is similar to that of the equal diameter part 201, and when the transition section 302 rotates a certain angle to make one arc end face abut against the equal diameter part 201, the clamping member 300 cannot horizontally slide in the clamping groove 200 along the length extending direction of the rod. When the transition section 302 rotates by a certain angle to enable the non-arc end face, namely two planes are parallel to the end face of the diameter-variable portion 202, the clamping piece 300 can slide along the clamping groove 200, so that the relative positions of the two rod pieces are changed, the adjustment of the hinged position is realized, and the instantaneous center position demonstration of the four-bar mechanism with different angles or shapes is realized. The locking portion 303 may be a nut, and the corresponding curved end surface of the transition section 302 is provided with an external thread. When adjusting the position of joint spare, locking portion 303 can be rotated down, separate two member bars, make changeover portion 302 certain angle in the draw-in groove 200 internal rotation of a member bar, make its planar surface parallel with variable diameter portion 202, slip joint spare 300 to the suitable position of current member bar, then make joint spare 300 rotatory, make an arc surface of changeover portion 302 support with the arc type surface of constant diameter portion 201 and hold, changeover portion 302 can not slide in draw-in groove 200, then establish another member bar cover on the surface of changeover portion 302, locking portion 303 is closed soon again, thereby realize the change at the articulated position of two member bars. In order to facilitate the free rotation of the two rods, the diameter of the constant diameter portion 201 should be set larger than the diameter of the arc-shaped end surface of the transition section 302.

In order to better rotate each rod piece and demonstrate the track of the instant center in the rotating process of the rod piece, namely the pole track, the utility model also comprises a spacing component 5 and a painting brush 6, wherein the spacing component 5 is arranged between the first rod piece and the base 100; one end of the spacer assembly 5 is detachably connected to the base 100, and the other end of the spacer assembly 5 is detachably connected to the sleeve segment 301 of the clip 300 of the first rod 1. Spacer assembly 5 offsets the rods as a whole from base 100 a distance to accommodate brush 6. Sleeve segment 301 has an inner surface that snaps or threads onto brush 6 or spacer assembly 5.

The non-first rod 1 is provided with a clamping piece 300, namely a painting brush 6 is arranged on a sleeve section 301 between the second rod and the third rod and between the third rod and the fourth rod, and the painting brush 6 is detachably connected with the sleeve section 301. Painting brush 6 can show corresponding prompt center moving trajectory when rotating the member, and the position change of better show prompt center lets the religion observe audio-visually.

Preferably, the lengths of the first pin 1, the second pin 2, the third pin 3, or the fourth pin 4 are identical. This form of the rod has a very good interchangeability.

In order to facilitate distinguishing and improve the effect of teaching demonstration, the first rod piece 1, the second rod piece 2, the third rod piece 3 or the fourth rod piece 4 are made of thin plate-shaped materials, and the colors of the rod pieces are different from each other. The color of brushes 6 on the corresponding different rods may also be different.

The utility model discloses during the use, earlier on base 1 fixed set up interval subassembly 5 to the position of fixed first member 1, then articulated second member 2, then install fourth rod 4 on first member 1, at last with third member and second member and fourth rod hinge connection, rotatory or remove non-fixed member to suitable position or angle, lock each joint spare 300, make between each member can not the straight line slip and can only rotate. Then the base 1 is placed horizontally or vertically. If the trace of the instant center needs to be demonstrated, the painting brush 6 needs to be installed on the clamping piece 300 arranged on the non-first rod piece 1, and then the movable rod piece is pushed so as to drive the painting brush 6 to rotate.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (9)

1. A mechanical instant center demonstration teaching aid is characterized in that: comprises a base (100), a first rod piece (1), a second rod piece (2), a third rod piece (3) and a fourth rod piece (4);

the first rod piece (1) is relatively fixed with the base (100); the first rod piece (1) is arranged along the length extending direction of the base (100);

one end of the second rod piece (2) is hinged with the first rod piece with a position locking function, and the other end of the second rod piece (2) extends outwards in the direction far away from the first rod piece (1); the second rod piece (2) and the first rod piece (1) form an included angle;

one end of the third rod piece (3) is hinged with the second rod piece (2) with a position locking function, and the other end of the third rod piece (3) extends towards the direction far away from the second rod piece (2);

one end of the fourth rod piece (4) is hinged with the first rod piece (1) with a position locking function, and the other end of the fourth rod piece (4) extends towards the direction far away from the first rod piece (1); the third rod piece (3) is also hinged with the fourth rod piece (4).

2. A mechanical instant center demonstration teaching aid as claimed in claim 1, wherein: the first rod piece (1), the second rod piece (2), the third rod piece (3) or the fourth rod piece (4) are provided with clamping grooves (200) which are linearly arranged along the length extending direction of the first rod piece, clamping pieces (300) are arranged in the clamping grooves (200), and the clamping pieces (300) are hinged or connected with the rod pieces connected with the clamping pieces in a sliding mode.

3. A mechanical instant center demonstration teaching aid as claimed in claim 2, wherein: the clamping groove (200) comprises a plurality of equal-diameter parts (201) and reducing parts (202); the constant diameter parts (201) and the variable diameter parts (202) are arranged in a staggered manner; the diameter of the constant diameter part (201) is larger than that of the variable diameter part (202).

4. A mechanical instant center demonstration teaching aid as claimed in claim 3, wherein: the clamping piece (300) comprises a sleeve section (301) and a transition section (302), and the sleeve section (301) is fixedly connected with the transition section (302); the transition section (302) is sleeved with a locking part (303), and the locking part (303) is fixedly connected with the transition section (302); the transition section (302) has a profile similar to the shape of the card slot (200).

5. A mechanical instant center demonstration teaching aid as claimed in claim 4, wherein: the radial cross section profile of the transition section (302) is a rounded rectangle, the arc-shaped end face of the transition section (302) is propped against the equal-diameter part (201) of the clamping groove (200), and the distance between the non-arc-shaped end faces of the transition section (302) is adapted to the width of the variable-diameter part (202).

6. A mechanical instant center demonstration teaching aid as claimed in claim 4, wherein: the device also comprises a spacing component (5), wherein the spacing component (5) is arranged between the first rod piece and the base (100); one end of the spacing component (5) is detachably connected with the base (100), and the other end of the spacing component (5) is detachably connected with the sleeve section (301) of the clamping piece (300) on the first rod piece.

7. The instant mechanics demonstration teaching aid of claim 6, wherein: a painting brush (6) is also arranged on a sleeve section (301) of the clamping piece (300) arranged on the non-first rod piece (1), and the painting brush (6) is detachably connected with the sleeve section (301).

8. A mechanical instant center demonstration teaching aid as claimed in claim 1, wherein: the lengths of the first rod piece (1), the second rod piece (2), the third rod piece (3) or the fourth rod piece (4) are completely the same.

9. A mechanical instant center demonstration teaching aid as claimed in claim 1, wherein: the first rod piece (1), the second rod piece (2), the third rod piece (3) or the fourth rod piece (4) are made of thin plate-shaped materials, and the colors of the rod pieces are different from each other.

Images