阅读说明：本技术 三维打印机树脂补给方法 (Three-dimensional printer resin replenishing method ) 是由 P.S.特纳 于 2018-02-20 设计创作，主要内容包括：三维打印机包括容器、光引擎、固定件、移动机构、传感器和控制器。容器用于容纳液态可光固化树脂,并且包括透明片,所述透明片限定下表面,可通过所述透明片照射树脂。光引擎被设置和配置为选择性地通过透明片照射树脂。固定件用于支撑三维制品,所述三维制品具有与透明片呈面向关系地浸入在树脂中的下表面。移动机构被配置为可控地平移固定件,以调节下表面在透明片上方的竖直高度。传感器被配置为监测三维制品上的树脂的动态竖直阻力。(Three-dimensional printer includes container, light engine, fixing piece, mobile mechanism, sensor and controller.For container for accommodating liquid photocurable resin, and including slide, the slide limits lower surface, can irradiate resin by the slide.Light engine is set and is configured to irradiate resin optionally through slide.Fixing piece is used to support three-dimensional article, and the three-dimensional article has the lower surface being immersed in slide in facing relation in resin.Mobile mechanism is configured as controllably translating fixing piece, to adjust vertical height of the lower surface above slide.Sensor is configured as the vertical resistance of dynamic of the resin on monitoring three-dimensional article.)

1. three-dimensional (3D) printer, comprising:

Container, for accommodating liquid resin, the container has slide, can irradiate resin by the slide；

Light engine is arranged to irradiate resin optionally through the slide；

Fixing piece is used to support 3D product, and thus the lower surface of 3D product and the slide are immersed in tree in facing relation In rouge；

Mobile mechanism, for controllably translating the fixing piece, thus, it is possible to control the lower surface of 3D product and the slide Between vertical distance；

Sensor is configured as monitoring the dynamic vertical force on the lower surface；

Controller is configured as:

(a) lower surface of 3D product is located in from the operating distance that the slide separates；

(b) light engine is activated, selectively resin layer to be cured on the lower surface；

(c) it is one or many to repeat (a) and (b)；

(d) mobile mechanism is activated, to be made the lower surface translate up distance D according to pumping circulation, and and it is backward Under move to the operating distance；

(e) simultaneously with (d), the signal from the sensor is monitored, the signal designation is applied in the lower surface of 3D product On dynamic force；

(f) it is based at least partially on the analysis of the signal from the sensor and updates at least one pumping circulation parameter；With And

(g) step (a) to (f) is repeated, until completing 3D product.

2. it is according to claim 1 three-dimensional (3D) printer, wherein the sensor directly measure be applied to it is described solid Determine the vertical force of part.

3. three-dimensional (3D) printer according to claim 1, wherein based on the signal from the sensor, adjust in real time Save the translational velocity of the lower surface.

4. three-dimensional (3D) printer according to claim 3, wherein if the signal designation dynamic from the sensor The size that power has is more than the specified control upper limit, then reduces translational velocity.

5. three-dimensional (3D) printer according to claim 3, wherein if the signal designation dynamic from the sensor The size that power has is less than specified control lower limit, then increases translational velocity.

6. three-dimensional (3D) printer according to claim 3, wherein if dynamic force is less than control relative to the slope of time Lower limit processed, then increase translational velocity.

7. three-dimensional (3D) printer according to claim 1, wherein translated up in the lower surface from the slide When, dynamic force increases, and then declines, the real-time analysis in response to dynamic force relative to the time, stops translating up in real time.

8. three-dimensional (3D) printer according to claim 1, wherein the controller is configured as based on dependence on parameter And pumping circulation is limited, the dependence on parameter keeps pumping circulation at least related to the geometry of 3D product.

9. three-dimensional (3D) printer according to claim 8, wherein signal of the analysis from the sensor, and make The dependence on parameter is updated for response.

10. three-dimensional (3D) printer according to claim 9, wherein update the dependence on parameter and be based on modification lookup Table.

11. three-dimensional (3D) printer according to claim 9, wherein it is new based on being directed toward to update the dependence on parameter Look-up table.

12. three-dimensional (3D) printer according to claim 9, wherein update the dependence on parameter and be based on adjustment function Parameter.

13. three-dimensional (3D) printer according to claim 9, wherein the dependence on parameter is based in response to being analyzed Signal and the multiplication factor that updates.

14. three-dimensional (3D) printer according to claim 1, wherein step (a) includes incrementally rising the lower surface Rise is from d, and wherein, four times of D at least equal to d.

15. three-dimensional (3D) printer according to claim 14, wherein 10 times of D at least equal to d.

16. it includes accommodating resin and in resin that the 3D printer, which has, using the method for 3D printer manufacture 3D product Lower portion has the container of slide, which comprises

(a) lower surface of 3D product is located in above the slide close to building plane；

(b) light of pixelation is projected upwards through the slide, with selectively will be in resin solidification to the lower surface；

(c) it is one or many to repeat (a) and (b)；

(d) execute pumping circulation, the pumping circulation include the lower surface is increased to building plane top, and and After reduce the lower surface, thus to feed resin between the lower surface and the slide close to the building plane；

(f) simultaneously with pumping circulation, the signal from sensor is monitored, the signal designation is applied in during pumping circulation Dynamic force on the lower surface；And

(g) analysis at least based on the signal from the sensor and update pumping circulation parameter.

17. three-dimensional (3D) printer according to claim 16, wherein during (d), in response to the signal, in real time Modify the pumping circulation.

18. three-dimensional (3D) printer according to claim 16, wherein updating the pumping circulation includes that optimization pumping follows Correlation between ring parameter and the geometry of 3D product.

19. three-dimensional (3D) printer according to claim 16, wherein the pumping circulation parameter is included in the pumping Vertical translational velocity during circulation.

20. three-dimensional (3D) printer according to claim 16, wherein the pumping circulation parameter includes for the pump Send the vertical translation distance D of circulation.

Technical field

This disclosure relates to for the device and method by energy-curable material manufacture solid three-dimensional (3D) product.More specifically Ground, this disclosure relates to the mode of the speed of three-dimensional (3D) printer of Optimum utilization light-curable resin and output quality.

Background technique

The use of three-dimensional (3D) printer is increasing sharply.The 3D printer of one type includes having overall operation former The photocuring printer of reason, the operating principle include selectivity solidification and hardening radiation-curable (photocurable) liquid tree Rouge.Typical photocuring system include the receiving container for keeping curable resin, the mobile mechanism for being connected to support surface and Controllable light engine.Photocuring system forms three-dimensional (3D) product and selectively solidifying light-curable resin layer.

In a system embodiment, container includes slide, and the slide forms a part of the lower surface of container. Support surface is located in above slide, and is in facing relation with slide.Follow the steps below: (1) mobile mechanism positions Support surface, thus light-curable resin thin layer is between support surface and slide.(2) light engine by the light of pixelation to On pass through slide, selectively light-curable resin layer to be cured on support surface.(3) mobile mechanism then passs Increase ground lift support surface.Repeat step (2) and (3), to form three-dimensional (3D) product, three-dimensional (3D) product with it is saturating The bright lower surface in facing relation.

One challenge is slide by cured polymer " pollution ".It is desirable that polymer will be only in support surface and 3D Solidify on the lower surface of product.But some polymer can solidify on lower window.Over time, on window Cured polymer will interfere the appropriate operation of 3D printer.In addition, lower window can be adhered in lower surface.In order to overcome this to ask Topic, has used various solutions, including provides release coating on lower window and/or use chemical inhibitor, to prevent Resin solidifies on or near lower window.

Another challenge that such system has is that the supply of new resin how is maintained at the building plane close to lower surface. When the lower surface of 3D product has solid and big area of section, resin can become to be depleted at building plane.3D product The up and down motion of lower surface can be used for feeding thin resin layer.This up and down motion can apply stress on the lower surface of 3D product, lead Cause the decline in quality.These stress can be reduced by slowing down up and down motion, but will lead to the longer processing time.It is desirable that mentioning For the system of high speed operation, and do not decline in the quality of 3D product.

Summary of the invention

In the first aspect of the disclosure, three-dimensional (3D) printer includes container, light engine, fixing piece, mobile mechanism, biography Sensor and controller.For container for accommodating liquid photocurable resin, and including slide, the slide limits lower surface At least part, can pass through the slide irradiate resin.Light engine is set and is configured to optionally through slide Irradiate resin.Fixing piece is used to support three-dimensional (3D) product, and thus the lower surface of 3D product is soaked with slide in facing relation Enter in resin.Mobile mechanism is configured as controllably translating fixing piece, thus can control lower surface and the slide of 3D product Between vertical distance.Sensor is configured as the dynamic vertical force on monitoring lower surface.Controller is configured as :(a) by 3D The lower surface of product is located in from the operating distance separated from slide；(b) light engine is activated, selectively to consolidate resin layer Change onto lower surface；(c) it is one or many to repeat (a) and (b)；(d) mobile mechanism is activated, to make following table according to pumping circulation Translation distance D upwardly, and operating distance is then moved to downwards；(e) simultaneously with (d), the signal from sensor is monitored, The signal designation is applied in the dynamic force on the lower surface of 3D product；(f) it is based at least partially on the letter from sensor Number analysis and update pumping circulation；And step (a) to (f) (g) is repeated, until completing 3D product.

In one embodiment, light engine includes light source and spatiality optical modulator.The operation of spatiality optical modulator, with The pixel element across building plane is selectively controlled, resin is selectively solidificated on the building plane.One In a embodiment, spatiality optical modulator is digital mirror device.Spatiality optical modulator receives untreated light from light source, and Reflection or transmitting pixelation and processed light.Light engine includes optical device, and the optical device transmits processed light To the building plane of the lower surface in resin and close to 3D product.

In another embodiment, sensor is vibrotron press, and the vibrotron press can sense compression and/or tensioning In dynamic change.Mountable energy converter, thus it directly senses the vertical force for being applied to fixing piece.

In yet another embodiment, controller electrically connect and/or wireless connections to light engine, mobile mechanism and to sensing Device.Controller includes processor, and the processor is connected to information-storing device.Information-storing device includes the non-of store instruction Temporary or non-volatile memory device, when being executed by a processor, described instruction handle the signal from sensor, and control Light engine processed and mobile mechanism.Controller can be accommodated in single IC(integrated circuit) or multiple IC in.Controller can be set In 3 D-printing system at a position or distribution in mutiple positions.

In further embodiment, based on the signal from sensor, the flat of the lower surface of 3D product is adjusted in real time Move speed.In the first embodiment, if the size that the signal designation dynamic force from sensor has is more than in specified control Limit, then reduce translational velocity.In a second embodiment, if the signal designation dynamic force from sensor has relative to the time Size be more than the specified control upper limit, then reduce translational velocity.In the third embodiment, if the signal designation from sensor The size that dynamic force has is less than specified control lower limit, then increases translational velocity.In the fourth embodiment, if coming from sensor Signal designation dynamic force relative to the time slope be less than lower control limit, then increase translational velocity.

In further embodiment, when the lower surface of 3D product is translated up far from slide, dynamic force phase Time is increased, and is then declined.Real-time analysis in response to dynamic force relative to the time can stop flat upwards in real time It moves.When the size of dynamic force starts to decline rapidly, can stop translating up.

In another embodiment, controller is configured as limiting pumping circulation based on dependence on parameter, the parameter Correlation keeps pumping circulation parameter at least related to the geometry of the lower surface of 3D product.Pumping circulation parameter include pumping away from The translational velocity of lower surface from D and 3D product.In the first embodiment, look-up table makes pumping circulation parameter and lower surface geometry Form parameter is related.In the first embodiment, the analysis based on the signal from sensor updates look-up table.Implement second In example, functional relation keeps pumping circulation parameter related to lower surface geometric shape parameters.In a second embodiment, it is based on carrying out autobiography The analysis of the signal of sensor, renewal function relationship.

In yet another embodiment, resin flowing flow pattern can be limited between the lower surface and slide of 3D product.It is based on Reynolds number, it can be laminar flow or turbulent flow that resin, which flows flow pattern,.Pumping circulation is updated, to maximize Reynolds number, while maintaining laminar flow Flowing, and avoid turbulent flow.For very viscous resin, pumping circulation can also have the upper limit for dynamic force.

In further embodiment, step (a) includes that lower surface is incrementally increased to distance d.In first embodiment In, four times of D at least equal to d.In a second embodiment, 10 times of D at least equal to d.In the third embodiment, D is at least equal to d 50 times.In the fourth embodiment, 100 times of D at least equal to d.

In further embodiment, step (a) includes that lower surface is incrementally increased to distance d.In some embodiments In, distance d is in 10 to 100 microns of range.In certain embodiments, distance d can be about 30 microns.Distance D is according to such as The factor of the geometry of lower surface and change.In some embodiments, distance D is equal at least four times of d.

Detailed description of the invention

Fig. 1 is to depict the schematic block diagram of exemplary three dimensional (3D) print system.

Fig. 2 is to depict the flow chart for the illustrative methods for operating three-dimensional (3D) print system.

Fig. 3 is the height H(t for depicting the lower surface of three-dimensional (3D) product above slide) showing relative to time t Example property exemplary timing diagram.

Fig. 4 is to depict height H(t) and power F(t) exemplary schematic timing diagram relative to time t.It H(t is) three-dimensional Height of the lower surface of (3D) product above slide.It F(t) is the perpendicular of the dynamic change being applied on three-dimensional (3D) product Straight power.

Fig. 5 is the exemplary containers for accommodating resin and the top view of three-dimensional (3D) product with solid circles section.

Fig. 6 is the exemplary containers for accommodating resin and the side cross-sectional, view of three-dimensional (3D) product.

Specific embodiment

Fig. 1 is that the schematic block diagram of the embodiment of three-dimensional (3D) print system 2 indicates.What is indicated in Fig. 1 is to be mutually perpendicular to Axis X, Y and Z.Axis X and Y are transverse axis.In some embodiments, X and Y is also horizontal axis.Axis Z is central axis Line.In some embodiments, Z is vertical axis.In some embodiments, direction+Z is generally upward, and direction-Z is overall It is upper downward.

3 D-printing system 2 includes container 4, and the container 4 accommodates light-curable resin 6.Container 4 includes slide 8, institute State at least part that slide 8 limits the lower surface 10 of container 4.Light engine 12 is arranged to for light being projected upwards through transparent Piece 8, to solidify the layer of light-curable resin 6, to gradually form three-dimensional article 14.Three-dimensional article 14 is attached to fixing piece 16, and And it is thus supported by fixing piece 16.Mobile mechanism 18 is connected to fixing piece 14, for translating fixing piece 14 along vertical axis Z.

3 D-printing system 2 includes sensor 20, and the sensor 20 is configured as monitoring and is applied in three-dimensional article 14 On dynamic vertical force.In one embodiment, sensor 20 is to be arranged on changing in fixing piece 16 and/or mobile mechanism 18 Energy device, to sense the vertical force for being applied to fixing piece 16.Dynamic vertical force is mainly passed through the movement of resin 6 by three-dimensional article 14 It generates.

Controller 22 electrically connects or wireless connections are to light engine 12, mobile mechanism 18 and sensor 20.Controller 22 includes Processor 24, the processor 24 are connected to information-storing device 26.Information-storing device 26 includes the nonvolatile of store instruction Property or non-volatile memory device, when by processor 24 execute when, described instruction analysis and processing the signal from sensor 20, And control light engine 12 and mobile mechanism 18.Controller 22 is accommodated in single IC(integrated circuit) or multiple IC in.Control Device 22 may be disposed in 3 D-printing system 2 at a position or be distributed among multiple positions.

Three-dimensional article 14 has the lower surface 28 towards slide 8.Lead to as light engine 12 selectively applies luminous energy Cross slide 8, selectively polymerize the resin close to " building plane ", " the building plane " can be overlapped with lower surface 20 or Close to lower surface 20.This effect having is that resin layer is selectively building up on lower surface 28.In the control of controller 22 Under, mobile mechanism controls the distance between lower surface 28 and slide 8 H(t).

Fig. 2 is to depict the flow chart for the illustrative methods 30 that three-dimensional article 14 is formed using three-dimensional (3D) print system 2. Fig. 3 is H(t) example chart relative to time t, it can correspond to a part of method 30.The two will be discussed simultaneously.

According to step 32, the lower surface 28 of three-dimensional article 14 is located in the operating distance or height H of 8 top of slide_opPlace. Step 32 is described under t=0 by the left side of Fig. 3 chart.

According to step 34, light engine 12 is activated, resin layer is cured on lower surface 28.Step 34 corresponds to t in Fig. 3 Dotted line between=0 and t=t1.After the solidification of step 34, distance H(t) reduce the light having been added on lower surface 28 The thickness of solidified resin.The method then advances back to step 32, wherein lower surface is increased back to operation height H_op。

Before proceeding to step 36, step 32 and 34 one or many is repeated.These are portrayed as and are repeated twice by Fig. 3, But step 32 and 34 number of repetition it is alterable.Before proceeding to step 36, can not repeat completely, or repeatable 1,2, 3,4,5,6,7 or more times.Number of repetition may depend on various factors, such as, geometry, 6 rheology of resin of lower surface 28 Property and the curing depth into resin.At time t1 and time t2 or near, lower surface 28 incrementally increases distance d, with Operation height H appropriate is provided before operating light engine_op。

When lower surface 28 has relatively large geometry, resin 6 can not fully weigh between t=0 and t=t3 Newly it is filled between lower surface 28 and slide 8.Under sometime, the quality of resin adding layers is compromised.Then it can be performed " pumping circulation ".Exemplary pumping circulation is shown between time t=t3 and t=t7 according to Fig. 3.Lower surface 28 is transparent H(t is increased to above film 8)=H_pump.Lower surface 28 between t=t3 and t=t6 raised distance will be referred to as pumping away from From D.

According to step 36, it is based at least partially on the geometry of lower surface 28 and determines pumping circulation.Pumping circulation is also It may depend on resin properties, such as, viscosity.Pumping circulation limits D and VELOCITY DISTRIBUTION or curve, is included in t=t3 and t=t7 Between height H(t) relative to time t.

According to step 38, mobile mechanism 18 begins pumping circulation.According to step 40, is monitored simultaneously with pumping circulation and carry out autobiography The signal of sensor 20.Dynamic force or movement caused power of the signal designation by resin 6 on three-dimensional article 14.Show in Fig. 4 " idealization " dynamic force is distributed F(t out) relative to time t.This be it is Utopian be not depicted because practical chart can have Other " swings ", but be showing the conversion of main power.The top chart of Fig. 4 depicts between t=t3 and t=t6 H(t) relative to time t.Although it is linear (constant-slope) between each time that sports immunology is by Fig. 3 and Fig. 4, It is this is for illustrative purposes.Actual motion can be to be nonlinear, to optimize the resin between lower surface 28 and slide 8 Flow flow pattern.

It is vertical that the bottom chart of Fig. 4 depicts the dynamic detected between time t=t3 and t=t6 by sensor 20 Power F(t).Between t=t3 and t=t4, as lower surface 28 increases, the viscous drag of resin 6 causes slide 8 upward Bending.Slide 8 flexibly pulls return, and power is caused to increase.When resin 6 finally start substantially lower surface 28 and thoroughly When being flowed between bright 8, power F(t) start decline rapidly, as described between t=t4 and t=t5.Finally, under Surface 28 declines slower further from slide 28, power F(t) between t=t5 and t=t6, and the power be due to Caused by viscous drag by resin 6.

According to step 42, in response to 40 signal of analytical procedure, and simultaneously with 40 signal of analytical procedure, pump can be adjusted in real time Send movement.Unless it is described analysis force curve F(t has been determined) be not it is optimal, otherwise step 42 not necessarily occurs.There are wherein Several embodiments of invocation step 42, and be some exemplary embodiments below.

According to first embodiment, for power F(t), relative to time t, there are upper control limits between t3 and t4.Excessively high Power can lead to damage three-dimensional article 14, and possibly even damage slide 8.If described analysis shows that F(t) size surpassed Cross upper control limit, then reduce H(t) slope (its be equal to fixing piece 16 translate up speed) relative to t, so as to reduce for The peak force (peak value of curve is shown as in Fig. 4) of pumping circulation.

According to second embodiment, for power F(t), relative to the slope of time t, there are controls between times t 3 and t 4 The upper limit.If the size of the analysis instruction slope of step 40 is more than upper control limit, reduces translate up speed (H(t) phase in real time For the slope of t), to reduce the peak force for pumping circulation.

According to third embodiment, for power F(t), there are lower control limits at specific time t.Too low power F(t) instruction The chance for increasing the building rate for three-dimensional article 14, without adverse effect.If the analysis of step 40 indicates power F (t) size is lower than lower control limit, then increase lower surface 28 translates up rate (it is equal to height H(t) relative to time t Slope).

According to fourth embodiment, for F(t between t3 and t4) relative to the slope of time t, there are lower control limits.It crosses Low slope indicates the chance for increasing the building rate for three-dimensional article 14, without adversely affecting.If the analysis Show F(t) be lower than lower control limit relative to the t slope of curve, then increase lower surface 28 translates up rate.

According to the 5th embodiment, expection chart of the pumping circulation being carrying out based on power F(t) relative to time t.It is based on The analysis, it may be determined that, time t4 than expected earlier occur-in other words, power F(t) start than expected earlier rapidly Decline.Then it can temporarily shorten pumping circulation by reducing time t=t6 and t=t7.This situation is increased for three-dimensional The building rate of product 14, while still ensuring that the resin between lower surface 28 and slide 8 flows again completely.

According to step 44, the pumping circulation from t=t3 to t=t7 is completed.Step 44 is actually overlapped with step 32, In, lower surface is positioned again at operating distance H_opPlace.The circulation of repeatable step 32 to 44, until completing three-dimensional article 14.

According to step 46, store new dependence on parameter, the dependence on parameter make pumping circulation at least with lower surface 28 Geometry and may other parameters it is related.This new dependence on parameter can be used for the subsequent repetition of step 32 to 44.This Various embodiments can be used in dependence on parameter.

In the first embodiment, dependence on parameter is limited by look-up table.According to first embodiment, step 46 includes that modification is looked into Table is looked for, the look-up table keeps pumping circulation and various input variables (such as, the geometry of lower surface 28) related.

In a second embodiment, dependence on parameter is limited by one or more functional relations, and the functional relation makes to pump It recycles related to the geometry of lower surface 28.Functional relation includes function parameter, such as, multiplication constant.Implement according to second Example, step 46 is including modifying one or more function parameters, and thus Modification growth function relationship.

In the third embodiment, dependence on parameter by one or more look-up tables and one or more functional relations combination It limits.Step 46 may include the modification for look-up table and/or functional relation.

Fig. 5 and Fig. 6 is simplified illustration, for showing the simple geometric shape of cylindrical three-dimensional product 14, under discussing The purpose of the geometry on surface 28.Fig. 5 is the top view for accommodating the container 4 and three-dimensional article 14 of resin 6, and Fig. 6 is Side view.Required pumping distance D is more and more related to radius R is flowed into, and the inflow radius R is round three-dimensional article 14 Lateral radius.Therefore, for such simple geometry, look-up table can make pumping distance D related to R.More complicated geometry Shape will not have such simple correlation, but for such geometry, can estimate equivalent inflow radius R.Pass through benefit Correlation can be improved automatically with the time for given resin 6 with method 30.

As the lower surface 28 of three-dimensional article 14 is increased to 8 top of slide, resin is flowed into, as indicating arrow 48. If translational velocity H(t) relative to t there is sufficiently low size, it will be laminar flow that resin, which flows 48 flow patterns, and flow arrow Amount would tend to be uniformly radially inward.But with H(t) relative to t increasing above some threshold value, resin flows 48 flow patterns Become turbulent flow and irregular.Such flowing flow pattern is not optimal.It is to become turbulent flow in flowing that optimum resin, which flows 48 rates, Before for the upper limit of Laminar Flow.The executable method 30 including step 42 and 46, to provide the translational velocity of highest size (height H(t) is relative to time t), wherein resin flowing 48 is laminar flow, and is no more than the upper limit of dynamic force.

The variable for limiting pumping circulation can significant changes.The correlation of several variables is required with best laminar flow flow operation. Effective radius (flowing into distance) R of given material layer can significant changes.Smaller effective radius can be in 1 to 5 millimeter of range. Bigger effective radius range can be at 5 to 500 millimeters or in bigger range.

The rheological behavior and geometry combinations of resin 6, with the best pumping circulation of determination.According to 28 geometric form of lower surface Shape, 6 rheological characteristic of resin and may other factors, pumping circulation may include as low as 100 to 300 microns or greatly to 500 to 5000 The pumping distance of micron.Slope of the translational velocity (height H(t) relative to time t) it can also be widely varied.Acceptable maximum, force F(t)_maxDepending on the factor including 28 geometry of 6 rheological characteristic of resin and lower surface.For given Resin Rheology, this can By find for give geometry power F(t) boundary be determined.

Above-described specific embodiment and its application exclusively for the purposes of illustration, and are not excluded for being wanted by appended right The modifications and variations that the range asked covers.