阅读说明：本技术 一种新型点漆机 (Novel point lacquer machine ) 是由 张兴良 于 2020-12-05 设计创作，主要内容包括：本发明公开了一种新型点漆机,包括机架及设置在机架顶部的工作台,机架上设置有点漆装置及用于驱动点漆装置在三维方向运动的三向驱动装置,三向驱动装置包括用于驱动点漆装置前后移动的前后进给机构、用于驱动点漆装置左右移动的左右进给机构及用于驱动点漆装置上下移动的上下进给机构,点漆装置包括气动阀及点漆组件,点漆组件包括针架,针架上设置有六根点漆管,任一点漆管上均连接有两个点漆头,点漆头上均设置有三根点漆针。本发明的有益效果：本发明设置有点漆装置及用于驱动点漆装置在三维方向运动的三向驱动装置,能够一次性对工件多个部位进行点漆,加工效率高,能够适用于大批量生产的需要。(The invention discloses a novel paint spot machine, which comprises a rack and a workbench arranged at the top of the rack, wherein a paint spot device and a three-dimensional driving device used for driving the paint spot device to move in a three-dimensional direction are arranged on the rack, the three-dimensional driving device comprises a front feeding mechanism used for driving the paint spot device to move back and forth, a left feeding mechanism and a right feeding mechanism used for driving the paint spot device to move left and right, and an up-and-down feeding mechanism used for driving the paint spot device to move up and down, the paint spot device comprises a pneumatic valve and a paint spot assembly, the paint spot assembly comprises a needle frame, six paint spot pipes are arranged on the needle frame, any paint spot pipe is connected with two paint spot heads, and three paint spot needles are arranged on the paint spot. The invention has the beneficial effects that: the three-dimensional point painting device is provided with the point painting device and the three-dimensional driving device for driving the point painting device to move in the three-dimensional direction, so that the point painting device can perform point painting on a plurality of parts of a workpiece at one time, has high processing efficiency and can meet the requirement of mass production.)

1. A novel point lacquer machine which characterized in that: comprises a frame (1) and a workbench (2) arranged at the top of the frame (1), wherein a point paint device and a three-way driving device used for driving the point paint device to move in a three-dimensional direction are arranged on the frame (1), the three-way driving device comprises a front feeding mechanism, a rear feeding mechanism, a left feeding mechanism, a right feeding mechanism and an upper feeding mechanism, the front feeding mechanism and the rear feeding mechanism are used for driving the point paint device to move back and forth, the left feeding mechanism and the right feeding mechanism are used for driving the point paint device to move left and right, the upper feeding mechanism and the lower feeding mechanism are used for driving the point paint device to move up and down, the point paint device comprises a pneumatic valve (3) and a point paint component, the point paint component comprises a needle frame (4), six point paint tubes (5) are arranged on the needle frame (4), any point paint tube (5) is connected with two point paint heads (6), three point paint needles (7) are arranged on the point paint heads (, all be connected with control hose (9) on some lacquer pipe (5), the one end and pneumatic valve (3) intercommunication each other of some lacquer pipe (5) are kept away from in control hose (9).

2. A new paint spot-painting machine according to claim 1, characterized in that: front and back feed mechanism include removal seat (10) of sliding connection on workstation (2) and with remove the power component one that seat (10) are connected, power component one includes driving motor (11) and sets up first lead screw (12) on driving motor (11) output, threaded connection has sliding block (13) on first lead screw (12), sliding block (13) are fixed on removing seat (10).

3. A new paint spot-painting machine according to claim 2, characterized in that: control feed mechanism includes support frame (14) and the power component two of being connected with support frame (14), power component two includes rotating electrical machines (15) and sets up second lead screw (16) on rotating electrical machines (15) output, sliding tray (17) have been seted up at removal seat (10) top, second lead screw (16) rotate to be connected inside sliding tray (17), threaded connection has two (18) of sliding block of fixing on support frame (14) on second lead screw (16), sliding block two (18) sliding connection is inside sliding tray (17).

4. A new paint spot-painting machine according to claim 3, characterized in that: feed mechanism is including being used for installing mounting panel (19) of needle frame (4) and the power component three of being connected with mounting panel (19), power component three is including fixing elevator motor (20) on support frame (14) and setting third lead screw (21) on elevator motor (20) output, mounting panel (19) threaded connection is on third lead screw (21), mounting panel (19) both ends sliding connection has spacing slide bar (22), spacing slide bar (22) fixed connection is on support frame (14).

5. A new paint spot-painting machine according to claim 2, characterized in that: and guide sliding rods (23) are arranged on two sides of the workbench (2), and guide sliding blocks (24) which are connected to the guide sliding rods (23) in a sliding mode are arranged on two sides of the moving seat (10).

6. A new paint spot-painting machine according to claim 1, characterized in that: the workbench (2) is provided with a support bedplate (25), and the support bedplate (25) is divided into a plurality of object placing spaces (27) through a partition fence (26).

7. A novel paint spot-painting machine as claimed in claim 6, characterized in that: put inside all being provided with of thing space (27) and putting thing groove (28), put thing groove (28) and install inside putting thing space (27) for detachably.

8. A novel paint spot-painting machine as claimed in claim 7, characterized in that: the article placing groove (28) is connected with a fixing bolt (29), and an installation screw hole (30) matched with the fixing bolt (29) is formed in the inner bottom wall of the article placing space (27).

9. A new paint spot-painting machine according to claim 3, characterized in that: the driving motor (11), the rotating motor (15) and the lifting motor (20) are programmable servo motors.

Technical Field

The invention relates to the technical field of paint dispensing equipment, in particular to a novel paint dispensing machine.

Background

Domino is a cuboid domino made of wood, bone or plastic. When playing, the domino pieces are arranged in a line at a certain interval, the first domino piece is slightly knocked down, and the rest domino pieces generate chain reaction and fall down in sequence. Domino is usually painted with patterns of different colors, the patterns are usually formed by spot painting, and the traditional spot painting is usually finished by hands in the industry, so that the processing efficiency is low and the defective rate is high. Therefore, the painting machine is adopted to replace the operation in the prior art, thereby greatly improving the processing speed, and even complex ornamentation and portrait can be finished within dozens of seconds, so that the traditional process is dust-resistant.

The spot painting machine, also known as a filling painting machine and a coloring machine, can fill different colored paints into various objects with intaglio patterns on the surface, and is widely applied to objects requiring precise coloring, such as lacquerwares, metal calligraphy and painting, labels, portraits, ornamentations, badges and the like, and after coloring, the surface of the object has beautiful color and exquisite patterns. Before the existing paint spot machine is used, a program is written according to the content of a pattern, the moving path of the paint spot needle head is controlled through a process sequence, and finally a workpiece is fixed on a workbench, so that the needle head can move according to the set path to perform paint spot, and the automation degree is high.

However, the existing paint spot-painting machine is usually only provided with a single paint spot-painting needle head, and the single paint spot-painting needle head can only correspond to one position of a workpiece, so that only one position can be spotted at a time, a plurality of positions of the workpiece can not be painted at one time, the machining efficiency is still not high enough, and the machine can not be suitable for the requirement of mass production.

Therefore, a new solution is needed to solve this problem.

Disclosure of Invention

The invention aims to solve the problems, and provides a novel paint spot machine which can perform paint spot on a plurality of parts of a workpiece at one time, has high processing efficiency and can meet the requirement of mass production.

The invention realizes the aim through the following technical scheme, a novel paint dotting machine comprises a rack and a workbench arranged at the top of the rack, wherein a paint dotting device and a three-way driving device for driving the paint dotting device to move in a three-dimensional direction are arranged on the rack, the three-way driving device comprises a front feeding mechanism, a rear feeding mechanism, a left feeding mechanism, a right feeding mechanism and an up feeding mechanism, the front feeding mechanism is used for driving the paint dotting device to move back and forth, the left feeding mechanism is used for driving the paint dotting device to move left and right, the up feeding mechanism is used for driving the paint dotting device to move up and down, the paint dotting device comprises a pneumatic valve and a paint dotting component, the paint dotting component comprises a needle frame, six paint dotting tubes are arranged on the needle frame, any one of the paint dotting tubes is connected with two paint dotting heads, the three paint dotting needles are arranged on the paint dotting, and one end of the control hose, which is far away from the paint dispensing pipe, is communicated with the pneumatic valve.

By adopting the technical scheme, as the paint dotting device and the three-way driving device for driving the paint dotting device to move in the three-dimensional direction are arranged, when the paint dotting operation is carried out on a workpiece, the workpiece can be placed on the workbench and arranged orderly, the flexible movement of the paint dotting device in the front-back, left-right and up-down directions can be realized according to a preset program, meanwhile, paint is injected into the paint dotting tube and the pneumatic valve is opened, the paint in the paint dotting tube can be injected into the paint dotting needle through the paint injection hose, then the paint is discharged through the paint dotting needle and the paint dotting is carried out on the workpiece, as the needle frame is provided with six paint dotting tubes, and any paint dotting tube is connected with two paint heads, and three paint dotting needles are arranged on the paint dotting heads, thirty-six dotting needles are arranged on the needle frame, so that the paint dotting device can realize the paint dotting of thirty-six parts of the workpiece at a, then the drive of rethread three-dimensional drive arrangement can once only carry out some lacquer to a plurality of positions of work piece, and machining efficiency is high, can be applicable to mass production's needs.

As a further arrangement of the invention, the front-back feeding mechanism comprises a moving seat slidably connected to the workbench and a first power assembly connected with the moving seat, the first power assembly comprises a driving motor and a first screw rod arranged on an output end of the driving motor, a first sliding block is in threaded connection with the first screw rod, and the first sliding block is fixed on the moving seat.

By adopting the technical scheme, when the point paint device is driven to move by the front and rear feeding mechanisms, the driving motor can be started, and the driving motor can drive the first screw rod to rotate, so that the moving seat is driven by the sliding block to move back and forth along the linear direction of the workbench, the moving is flexible and stable, and the efficiency is high.

As a further arrangement of the invention, the left and right feeding mechanism comprises a support frame and a second power assembly connected with the support frame, the second power assembly comprises a rotating motor and a second screw rod arranged on the output end of the rotating motor, the top of the moving seat is provided with a sliding groove, the second screw rod is rotatably connected inside the sliding groove, the second screw rod is in threaded connection with a second sliding block fixed on the support frame, and the second sliding block is in sliding connection inside the sliding groove.

Through adopting above-mentioned technical scheme, when moving through controlling feed mechanism drive point lacquer device, but start rotating electrical machines, rotating electrical machines can drive the second lead screw and rotate to can drive sliding block two and slide about the sliding tray is inside, thereby can drive the support frame and remove about removing the seat horizontal direction, remove in a flexible way and steady, efficiency is higher.

As a further arrangement of the invention, the up-and-down feeding mechanism comprises a mounting plate for mounting the needle frame and a third power assembly connected with the mounting plate, the third power assembly comprises a lifting motor fixed on the support frame and a third screw rod arranged on the output end of the lifting motor, the mounting plate is in threaded connection with the third screw rod, two ends of the mounting plate are in sliding connection with limit slide bars, and the limit slide bars are fixedly connected with the support frame.

Through adopting above-mentioned technical scheme, when moving through upper and lower feed mechanism drive point lacquer device, can start elevator motor, elevator motor can drive the third lead screw and rotate, and spacing through spacing slide bar for the mounting panel can only slide from top to bottom along the third lead screw, thereby can drive the mounting panel and reciprocate, and it is nimble and steady to remove, and efficiency is higher.

As a further arrangement of the invention, guide slide bars are arranged on two sides of the workbench, and guide slide blocks which are connected to the guide slide bars in a sliding manner are arranged on two sides of the moving seat.

Through adopting above-mentioned technical scheme, owing to be provided with the direction slide bar in workstation both sides, and be provided with the direction slider of sliding connection on the direction slide bar in removing the seat both sides, then when removing the seat and carrying out the back-and-forth movement along workstation linear direction, the direction slider can slide along direction slide bar linear direction thereupon, through the cooperation between direction slider and the direction slide bar for the removal of removing the seat is more steady smooth and easy, thereby has effectively guaranteed some lacquer quality.

According to the further arrangement of the invention, a support bedplate is arranged on the workbench, and a plurality of object placing spaces are formed on the support bedplate through division of the partition fence.

Through adopting above-mentioned technical scheme, owing to be provided with the support platen on the workstation, and be formed with a plurality of object spaces through the partition fence division on the support platen, then when carrying out some lacquer operations to the work piece, can arrange the object space inside on the support platen in side by side neatly with the work piece earlier, then put the object space and can arrange in order in rows the work piece of treating some lacquer to make things convenient for some lacquer operations, effectively promoted the machining efficiency of equipment.

As a further arrangement of the invention, the storage space is internally provided with storage grooves which are detachably arranged in the storage space.

Through adopting above-mentioned technical scheme, owing to all be provided with the thing groove of putting in putting thing space inside, and put the thing groove and install inside putting the thing space for detachably, then can arrange the thing groove internal sign indicating number row in with waiting to some lacquer work pieces, make things convenient for subsequent some lacquer operations, and when putting the thing groove and lead to becoming dirty or be infected with the lacquer mark because of long-term use, can pull down and clean alone putting thing groove from putting thing space inside, avoid causing the influence to the normal use of equipment, and prolonged the life who puts the thing groove greatly.

As a further arrangement of the invention, the article holding groove is connected with a fixing bolt, the bottom wall of the article holding space is provided with an installation screw hole matched with the fixing bolt,

through adopting above-mentioned technical scheme, owing to be connected with fixing bolt on putting the thing groove, and set up the installation screw that matches with fixing bolt on putting the thing space on the diapire, then will put the thing groove and install when putting the thing space inside, can be with inside fixing bolt screw in installation screw, through the threaded connection between fixing bolt and the installation screw, can realize putting the thing groove and putting the firm installation of thing space inside, and the dismouting operation is comparatively convenient simple.

As a further arrangement of the present invention, the driving motor, the rotating motor and the lifting motor all adopt programmable servo motors.

By adopting the technical scheme, because the driving motor, the rotating motor and the lifting motor all adopt programmable servo motors, the rotating speeds of the driving motor, the rotating motor and the lifting motor can be preset, so that the preset driving motor, the rotating motor and the lifting motor can be driven according to a fixed mode, the paint dispensing operation of the equipment can be carried out according to a preset program, and the using effect of the equipment is effectively ensured.

In conclusion, the invention has the following beneficial effects:

the three-dimensional point painting device is provided with the point painting device and the three-dimensional driving device for driving the point painting device to move in the three-dimensional direction, the point painting device can flexibly move in the front and back direction, the left and right direction and the up and down direction, the point painting device can perform point painting on thirty-six parts of a workpiece at a single point position, and then the three-dimensional driving device is driven to perform point painting on a plurality of parts of the workpiece at one time, so that the processing efficiency is high, and the three-dimensional point painting device can meet the requirement of mass production.

Drawings

FIG. 1 is a first schematic structural diagram of the present invention;

FIG. 2 is an enlarged schematic view of the structure at A in FIG. 1;

FIG. 3 is a second schematic structural view of the present invention;

FIG. 4 is an enlarged view of the structure at B in FIG. 3;

FIG. 5 is a schematic view of the present invention with the support platen removed;

FIG. 6 is a schematic view of a connection structure among the support frame, the mounting plate, the lifting motor, the third lead screw and the limiting slide rod.

Reference numerals: 1. a frame; 2. a work table; 3. a pneumatic valve; 4. a needle frame; 5. dispensing a paint pipe; 6. painting head dotting; 7. painting needles are dotted; 8. a paint injection hose; 9. a control hose; 10. a movable seat; 11. a drive motor; 12. a first lead screw; 13. a first sliding block; 14. a support frame; 15. a rotating electric machine; 16. a second lead screw; 17. a sliding groove; 18. a second sliding block; 19. mounting a plate; 20. a lifting motor; 21. a third screw rod; 22. a limiting slide bar; 23. a guide slide bar; 24. a guide slider; 25. a support platen; 26. a divider bar; 27. an object placing space; 28. a storage groove; 29. fixing the bolt; 30. and installing screw holes.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-4, a novel paint spot machine comprises a frame 1 and a workbench 2 arranged on the top of the frame 1, wherein a paint spot device and a three-way driving device for driving the paint spot device to move in three-dimensional directions are arranged on the frame 1, the three-way driving device comprises a front feeding mechanism, a rear feeding mechanism, a left feeding mechanism, a right feeding mechanism, a vertical feeding mechanism, a pneumatic valve 3 and a paint spot component, the pneumatic valve 3 is six, the paint storage tanks are two, the paint spot component comprises a needle frame 4, six paint spot pipes 5 are arranged on the needle frame 4, the paint spot pipes 5 are communicated with paint tanks (not marked in the figure), two paint spot heads 6 are connected to any paint spot pipe 5, and three paint spots 7 are arranged on the paint spot heads 6, the paint dispensing pipe 5 and the paint dispensing needle 7 are communicated with each other through a paint injection hose 8, the paint dispensing pipe 5 is connected with a control hose 9, and one end, far away from the paint dispensing pipe 5, of the control hose 9 is communicated with the pneumatic valve 3.

Referring to fig. 1-6, the front and rear feeding mechanism includes a moving base 10 slidably connected to the worktable 2 and a first power assembly connected to the moving base 10, guide slide bars 23 are disposed on both sides of the worktable 2, guide sliders 24 slidably connected to the guide slide bars 23 are disposed on both sides of the moving base 10, the first power assembly includes a driving motor 11 and a first lead screw 12 disposed on an output end of the driving motor 11, a first sliding block 13 is threadedly connected to the first lead screw 12, the first sliding block 13 is fixed to the moving base 10, the left and right feeding mechanisms include a support frame 14 and a second power assembly connected to the support frame 14, the second power assembly includes a rotating motor 15 and a second lead screw 16 disposed on an output end of the rotating motor 15, a sliding slot 17 is formed on a top of the moving base 10, the second lead screw 16 is rotatably connected to an inside of the sliding slot 17, the second sliding block 18 fixed to the support frame 14 is threadedly connected to the second lead screw 16, and the second sliding block 18 is connected inside the sliding groove 17 in a sliding manner, the up-and-down feeding mechanism comprises a mounting plate 19 for mounting the needle frame 4 and a third power assembly connected with the mounting plate 19, the third power assembly comprises a lifting motor 20 fixed on the support frame 14 and a third screw rod 21 arranged on the output end of the lifting motor 20, the mounting plate 19 is connected with the third screw rod 21 in a threaded manner, two ends of the mounting plate 19 are connected with limit slide rods 22 in a sliding manner, and the limit slide rods 22 are fixedly connected on the support frame 14, wherein the driving motor 11, the rotating motor 15 and the lifting motor 20 all adopt programmable servo motors, and the driving motor 11, the rotating motor 15 and the lifting motor 20 all adopt conductive sliding ring structures which are sliding ring conducting rings adopted in a winding type motor disclosed in the utility model with the publication No. CN201341054Y, thereby being mature prior art, and will not be described in detail herein.

Referring to fig. 1, 3 and 4, a supporting platen 25 is disposed on the worktable 2, a plurality of object placing spaces 27 are formed on the supporting platen 25 by dividing a partition 26, object placing grooves 28 are disposed inside the object placing spaces 27, the object placing grooves 28 are detachably mounted inside the object placing spaces 27, wherein fixing bolts 29 are connected to the object placing grooves 28, an external thread structure is disposed on the outer wall of the fixing bolts 29, mounting screw holes 30 matched with the fixing bolts 29 are disposed on the inner bottom wall of the object placing spaces 27, and an internal thread structure matched with the external thread structure is disposed on the inner wall of the mounting screw holes 30.

Because the point paint device and the three-way driving device for driving the point paint device to move in the three-dimensional direction are arranged, and the three-way driving device comprises the front and back feeding mechanism, the left and right feeding mechanism and the up and down feeding mechanism, when the point paint operation is carried out on a workpiece, the workpiece can be firstly placed on the workbench 2 and is orderly arranged, then according to a preset program, the front and back feeding mechanism can drive the point paint device to move back and forth, the left and right feeding mechanism can drive the point paint device to move left and right, the up and down feeding mechanism can drive the point paint device to move up and down, thereby the point paint device can flexibly move in three directions, meanwhile, paint is injected into the point paint pipe 5 and the pneumatic valve 3 is opened, the paint in the point paint pipe 5 can be injected into the point paint needle 7 through the paint injection hose 8, then is discharged through the point paint needle 7 and carries out point paint on the workpiece, because the needle frame, and any one point lacquer pipe 5 is connected with two point lacquer heads 6, and all be provided with three point lacquer needles 7 on point lacquer head 6, then be provided with thirty six point lacquer needles 7 altogether on needle frame 4, make point lacquer device can realize the point lacquer to thirty six positions of work piece in the single-point position, then rethread three-dimensional drive arrangement's drive, can once only carry out point lacquer to a plurality of positions of work piece, machining efficiency is high, can be applicable to the needs of mass production.

Because the front and back feeding mechanism, the left and right feeding mechanism and the up and down feeding mechanism are arranged, when the varnishing device is driven to move by the front and back feeding mechanism, the driving motor 11 can be started, the driving motor 11 can drive the first screw rod 12 to rotate, so that the moving seat 10 is driven to move back and forth along the linear direction of the workbench 2 by the first sliding block 13, the movement is flexible and stable, the efficiency is high, wherein, because the guide sliding rods 23 are arranged at the two sides of the workbench 2, and the guide sliding blocks 24 which are connected with the guide sliding rods 23 in a sliding way are arranged at the two sides of the moving seat 10, when the moving seat 10 moves back and forth along the linear direction of the workbench 2, the guide sliding blocks 24 can slide along the linear direction of the guide sliding rods 23, the movement of the moving seat 10 is more stable and smooth through the matching between the guide sliding blocks 24 and the guide sliding rods 23, thereby effectively ensuring the, can start rotating electrical machines 15, rotating electrical machines 15 can drive second lead screw 16 and rotate, thereby can drive two 18 horizontal slip in sliding tray 17 inside, thereby can drive support frame 14 and remove about removing along removing seat 10 horizontal direction, it is nimble and steady to remove, high efficiency, when moving through upper and lower feed mechanism drive point lacquer device, can start elevator motor 20, elevator motor 20 can drive third lead screw 21 and rotate, spacing through spacing slide bar 22, make mounting panel 19 only can follow third lead screw 21 and slide from top to bottom, thereby can drive mounting panel 19 and reciprocate, it is nimble and steady to remove, high efficiency.

Because the supporting bedplate 25 is arranged on the workbench 2, and the plurality of storage spaces 27 are formed on the supporting bedplate 25 by dividing the partition fence 26, when the painting operation is carried out on the workpiece, the workpiece can be firstly placed in the storage spaces 27 on the supporting bedplate 25 and arranged orderly, and then the storage spaces 27 can arrange the workpieces to be painted in sequence, thereby facilitating the painting operation, effectively improving the processing efficiency of the equipment, and because the storage slots 28 are arranged in the storage spaces 27 and the storage slots 28 are detachably arranged in the storage spaces 27, the workpieces to be painted can be placed in the storage slots 28 and arranged orderly, thereby facilitating the subsequent painting operation, and when the storage slots 28 become dirty or are stained with paint due to long-term use, the storage slots 28 can be detached from the interior of the storage spaces 27 and cleaned independently, thereby avoiding the influence on the normal use of the equipment, and prolonged the life of putting thing groove 28 greatly, wherein, owing to be connected with fixing bolt 29 on putting thing groove 28, and set up the installation screw 30 that matches with fixing bolt 29 on putting thing space 27 internal bottom wall, then when will putting thing groove 28 and install inside putting thing space 27, can be inside fixing bolt 29 screw in installation screw 30, through the threaded connection between fixing bolt 29 and the installation screw 30, can realize putting thing groove 28 firmly the installation inside putting thing space 27, and the dismouting operation is comparatively convenient simple.

Because the driving motor 11, the rotating motor 15 and the lifting motor 20 all adopt programmable servo motors, the rotating speeds of the driving motor 11, the rotating motor 15 and the lifting motor 20 can be preset, so that the preset driving motor 11, the preset rotating motor 15 and the preset lifting motor 20 can be driven according to a fixed mode, the painting operation of the equipment can be carried out according to a preset program, and the using effect of the equipment is effectively ensured.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may occur to those skilled in the art without departing from the principle of the invention, and are considered to be within the scope of the invention.