CN86205879U

CN86205879U - Automatic drawing instrument of link curves

Info

Publication number: CN86205879U
Application number: CN 86205879
Authority: CN
Inventors: 林风
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-08-12
Filing date: 1986-08-12
Publication date: 1987-09-09

Abstract

The utility model relates to a four link curve instrument used for drawing various planes, which can demonstrate a plurality of common plane four link mechanism forms: a crank-rocker mechanism, a double-crank mechanism and a double-rocker mechanism, and various practical link curves of the mechanisms can be drew. Drawing the curve can adopt an automatic or a manual method. Selecting the drawing method and adjusting the link length of the link mechanism have convenience. The instrument can draw the continuous closed link curves, and the instrument draw the continuous link curve which can reflect the moving velocity of the link point. The instrument can be served as a visual aid used for the teaching of the mechanical principle course, and the instrument can be applied to a mechanical design department and a regarding research unity.

Description

Automatic drawing instrument of link curves

The present invention relates to a kind of instrument of drawing multiple plane four coupler-point curves, be used for the teaching of mechanical principle course, it provides unprecedented practical teaching aid for the instruction mechanical principle course, also can use for scientific research and design department.

According to domestic and international about document at present, as introducing in U.S. ASME magazine, Soviet Union М а ш и н о в e д e н и e magazine and China's " mechanical principle " book, the linkage assembly teaching aid that is used for mechanical principle teaching is a lot, but mostly be simple manually teaching aid greatly, the major defect that exists is that these teaching aids are when drawing coupler-point curve, because the interference between bar and the bar is difficult to the coupler-point curve of sealing that draws.And the bar of each bar is long generally can't to be changed, and is difficult to the influence of the long comparison of deep discussion bar curve shape, also can't demonstrate the velocity variations rule of lever point in moving process.That these teaching aids use is both inconvenient, also out of true, and not talkative its is very desirable teaching aid.

At present when the factory of China and R﹠D institution's planing machine need be used linkage assembly or inquire into the coupler-point curve Changing Pattern, generally adopt experimental method and figure spectrometry.So-called experimental method is exactly according to the Known designs parameter, and mapping obtains relevant data repeatedly, makes the model of some cardboards or wood chip then and tests, and this method for designing is too loaded down with trivial details.So-called figure spectrometry is that the coupler-point curve atlas that utilizes compilation to compile comes the design plane linkage assembly, but though figure spectrometry simplified design, but the curve that collection of illustrative plates is collected is limited, so be difficult to break away from limitation, total adjusting lever length can not drawn arbitrarily that the instrument of all kinds of coupler-point curves comes intuitively, box lunch if any one.

The objective of the invention is to overcome the shortcoming of existing lanar four rod mechanism teaching aid, design a kind of instrument that can describe multiple plane four coupler-point curves automatically, draw coupler-point curve for teaching, design and scientific research department and use.

Automatical drawing apparatus of connecting rod curve of the present invention can be demonstrated modal basic system---several main pattern of planar linkage mechanism: crank and rocker mechanism, double-crank mechanism and double rocker mechanism.And can draw the various practical coupler-point curve of these three kinds of mechanisms, the method for curve plotting can adopt maneuver mode, also can adopt manual mode.The adjusting of the selection of drafting mode and bar length is all very convenient.The curve of being drawn can be continuously the coupler-point curve of sealing, also can draw out the interrupted coupler-point curve that can reflect the lever point movement velocity.The coupler-point curve of being drawn can be applied to engineering reality fully.

Embodiment of the present invention and instrument advantage have the following aspects:

(1), the time do not interfere with each other in motion in order to make each rod member of linkage assembly in the instrument, so, during design staggered up and down in the position of four rod members, so just can draw out the coupler-point curve of continuous sealing.Four rod members can be long with the clamp nut adjusting lever.All be carved with scale on the every bar, can show adjustment amount.This instrument can be drawn out the various coupler-point curves of crank and rocker mechanism, double-crank mechanism and double rocker mechanism.

(2), for the multiple needs of adapt teaching, design and scientific research, instruments design Cheng Jike is motor-driven, but manual operation again.When drawing coupler-point curve automatically, make motive power through two cover worm gears, worm reduction gear by a motor, make driving lever obtain the rotating speed that per minute about 1 changes.Draw coupler-point curve with this speed, both can guarantee render speed, can guarantee the quality of institute's curve plotting again.Use the belt transferring power between the two cover reduction gear, can play overload protective function.If when taking manual mode to draw coupler-point curve, as long as throw off power clutch just passable.

(3), when 5 ° of driving lever revolutions, utilize cam mechanism to make the pen of curve plotting make a dipping and heaving with penholder.Whole penholder and four-bar mechanism are along two upright guide rail knee-actions.Every curve is made up of 72 little segment of curve, can judge the speed of lever point in this place's motion by the length variations of little segment of curve.If certain section little segment of curve is longer, illustrate that then lever point is very fast in this place's movement velocity.Otherwise,, illustrate that then lever point is slower in this place's movement velocity if certain section little segment of curve is shorter.

(4), if want to draw out the coupler-point curve of continuous sealing with manual methods, can throw off the clutch coupling on the driving lever, at this moment cam mechanism is inoperative, rotates main drive shaft by hand and drives parallel motion and just can draw.

Now in conjunction with the following drawings embodiments of the invention are described in detail as follows:

Fig. 1 is: the automatical drawing apparatus of connecting rod curve outside drawing

Fig. 2 is: automatical drawing apparatus of connecting rod curve transmission synoptic diagram

Among the figure:

1, base plate 12, worm screw 25, connecting rod

2, frame 13, worm gear 26, bar

3, motor 14, belt 27, pen

4, the 1st grade of reduction gear 15, belt pulley 28, axle

(speed ratio is 1:21) 16, clutch coupling 29, axle

5, the 2nd grade of reduction gear 17, worm screw 30, follower lever

(speed ratio is 1:72) 18, worm gear 31, axle

6, guide rail 19, clutch coupling 32, axle

7, cam mechanism 20, main drive shaft 33, frame

8, four-bar mechanism 21, clamp nut 34, clamp nut

9, penholder 22, driving lever 35, clamp nut

10, adjust screw 23, axle 36, cam mechanism

11, shaft coupling 24, axle

The structure of automatical drawing apparatus of connecting rod curve as shown in Figure 1, instrument by base plate (1), frame (2), motor (3), the 1st grade of reduction gear (4), the 2nd grade of reduction gear (5), guide rail (6), cam mechanism (7), four-bar mechanism (8), penholder (9), adjust screw (10) and form.Frame (2) is fixed on the base plate (1), can utilize four levels of adjusting screw (10) adjustment frame (2) to base plate (1), during with assurance four-bar mechanism (8) motion, the nib on the penholder (9) is more or less the same with the dynamics that paper contacted that is fixed on base plate (1) when trace.Like this, not interrupted in the time of both can having guaranteed four-bar mechanism (8) motion, can guarantee that also drawn coupler-point curve line weight is even on paper.

Below according to Fig. 2: automatical drawing apparatus of connecting rod curve transmission synoptic diagram illustrates drive path.Drive worm screw (12) and this reduction gear of worm gear (13) (speed ratio is 1:21) by the motor (3) that is fixed on the frame (2), obtain the 1st grade of deceleration.Power reaches the belt pulley of axle on (15) through sewing machine belt (14), drives worm screw (17) through clutch coupling (16) and rotates.Worm screw (17) is formed the 2nd grade of reduction gear (speed ratio is 1:72) with worm gear (18).At this moment speed reduces to worm gear (18) per minute changes 1 commentaries on classics approximately.The rotation of worm gear (18) reaches main drive shaft (20) through clutch coupling (19).Bar (22) is the driving lever of four-bar mechanism (8), and it and being connected to of main drive shaft (20) are slidingly connected.Determine behind the good position fastening by clamp nut (21), axle (23) also is to be slidingly connected to be fixed by clamp nut (35) with driving lever (22), axle (23) is to be linked to each other by cradle head with axle (24), diaxon can relatively rotate along axis, bar (25) is exactly a connecting rod, and it is with axle (24), axle (28), and be slidingly connected can be fastening by nut (35).The pen (27) of drawing coupler-point curve can be gone up at connecting rod (25) by bar (26) and slide, determine good position after available clamp nut fix its position, axle (28) and spool (29) are for being rotationally connected, diaxon can relatively rotate along axis.Axle (29) can be gone up at follower lever (30) and slide, and fixes its position by nut (35).Axle (31) and follower lever (30) but being slidingly connected still for the fixed position.Axle (31) and axle (32) are for being rotationally connected, axle (32) is fixed on the frame (2) by clamp nut (34), lift four-bar mechanism (8) and penholder (9) is finished by cam mechanism (36), can make four-bar mechanism (8), penholder (9) do to be up and down the fluctuating of 4mm along upright guide rail (6).Because cam is installed on the worm shaft (17), again because this grade reduction gear speed ratio is 1:72, so the coupler-point curve of being drawn out is made up of 72 little segment of curve.

Apparatus of the present invention method of operating is as follows:

Before operation, earlier blank sheet of paper is fixed on base plate (1) with adhesive tape and goes up on the position of corresponding four-bar mechanism (8) below.Holdback clutch (19) make four-bar mechanism (8) be in can be manual state.Adjust the level that screw (10) is adjusted frame (2) with four.Then by degree of tightness nut (21), (34), (35) can adjuster bar (22), the length of (25), (30), adjusting lever is long than finishing according to the Grashof condition in the four-bar mechanism theory, for example: when the length of driving lever (22), connecting rod (25), follower lever (30), frame (33) is adjusted into 6cm, 18cm, 10cm, 20cm by scale respectively, at this moment four-bar mechanism is the crank and rocker mechanism pattern, and it is long than constituting double-crank mechanism or double rocker mechanism in like manner to change bar.Rotate driving lever (22) by hand, can on paper, depict the coupler-point curve of a complete closure.Motor-driven if desired drafting coupler-point curve, clutch coupling (16) and (19) can be combined, the power turn-on switch, motor (3) rotates, power is along the drive path transmission, pen (27) is promptly drawn out coupler-point curve on paper, instrument adjustment, easy to operate, and it is accurate rapidly, multiple functional to draw.

Claims

1, a kind of both can be automatic, but the continuous coupler-point curve of sealing of hand drawn again, also can draw out the Coupler Curve Drawing instrument of the coupler-point curve of forming by 72 little segment of curve, it is characterized in that it by base plate [1], frame [2], motor [3], the 1st grade of reduction gear [4], the 2nd grade of reduction gear [5], guide rail [6], cam mechanism [7], four-bar mechanism [8], penholder [9], adjust screw [10] and form:

(1), cam mechanism [7] is when four-bar mechanism [8] moves, utilize cam mechanism [7] to make four-bar mechanism [8] and penholder [9] do to be up and down the fluctuating of 4mm along two upright guide rails [6] that are fixed on the frame [2], the coupler-point curve of drafting is made up of 72 little segment of curve, is reflected the movement velocity of lever point;

(2), stagger up and down mutually in the position of four rod members [22] of four-bar mechanism [8], [25], [30], [33], be unlikely to interfere with each other, bar and bar space out, during curve plotting, pen is unlikely to bump on arbitrary bar, be carved with scale on the every bar, can show adjustment amount, adjust with adjustment nut [21], [34], [35];

(3), the 1st grade of reduction gear [4] reduction gear ratio is 121, the 2nd grade of reduction gear [5] reduction gear ratio is 1: 72, double reduction gear [4], [5] are to guarantee with two cover worm gears, worm speed-down, and making worm gear [18] per minute change 1 approximately changes, and two covering devices link to each other with the sewing machine belt and play overload protective function; In power transmission process, adopt two cover clutch couplinges [16], [19], the 1st cover clutch coupling [16] is used for the combination between the two cover reduction gear, may command is lifted the pen height simultaneously, the 2nd cover clutch coupling [19] with motor-driven, manual manipulation mode is relevant, but in conjunction with the time mobile operation, but manual operation during separation.